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Soluble intercellular adhesion molecule-1 (s-ICAM-1\\/s-CD54) in diffuse large B-cell lymphoma: association with clinical characteristics and outcome
M. J. Terol; M. Tormo; J. A. Martinez-Climent; I. Marugan; I. Benet; A. Ferrandez; A. Teruel; R. Ferrer; J. GarcĒa-Conde
Background: High serum levels of soluble intercellular adhesion molecule-1(s-ICAM-1\\/s-CD54) have been associated with adverse clinical features and poor outcome in chronic lymphocytic leukemia, Hodgkin's disease and non-Hodgkin's lymphoma, but their value in the different subtypes of non-Hodgkin's lymphoma has not been well addressed. Patients and methods: Our aim was to study the serum levels of s-ICAM-1 in diffuse large B-cell
Characterization of intercellular adhesion molecule-1 ectodomain (sICAM-1) as an inhibitor of lymphocyte function-associated molecule-1 interaction with ICAM-1.
Meyer, D M; Dustin, M L; Carron, C P
Intercellular adhesion molecule-1 (ICAM-1) is a member of the Ig superfamily, contains five Ig-like domains comprising the extracellular portion of the molecule, and interacts with lymphocyte function-associated molecule-1 (LFA-1), a member of the beta 2-integrin family. LFA-1/ICAM-1 interaction is important in a variety of cellular events including Ag-specific T cell activation and leukocyte transendothelial migration. Recently, a soluble circulating form of ICAM-1 has been detected in human serum that appears to result from the proteolytic cleavage of membrane ICAM-1. Native and recombinant soluble forms of ICAM-1 have been reported to inhibit LFA-1/ICAM-mediated adhesion in vitro, and it is conceivable that circulating forms of soluble ICAM-1 are regulators of LFA-1/ICAM-1-mediated cell-cell interaction in vivo. We have investigated the properties of the ICAM-1 ectodomain (sICAM453) as an inhibitor of LFA-1 interaction with ICAM-1 in cell- and molecule-based systems. The results show clearly that recombinant sICAM453 can inhibit LFA-1/ICAM-1 interaction. Soluble ICAM-1 inhibited LFA-1-mediated cell adhesion to immobilized sICAM453 and homotypic T-cell aggregation with IC50 in the 20 to 40 microM range. Definitive evidence that sICAM-1 can inhibit LFA-1 interaction with ICAM-1 was obtained by showing that the sICAM-1 inhibited the interaction between LFA-1 protein micelles and ICAM-1 immobilized on plastic. These results clearly show that sICAM453 can bind to LFA-1 and competitively inhibit ICAM-1/LFA-1-mediated cell-cell interaction, albeit at concentrations much greater than found in plasma. As a consequence, it is unlikely that sICAM-1 would antagonize ICAM-1/LFA-1-mediated cellular events in vivo. PMID:7561056
Soluble intercellular adhesion molecule-1 and clinical outcomes in patients with acute lung injury
Eisner, Mark D.; Parsons, Polly E.; Thompson, B. Taylor; Conner, Edward R.; Matthay, Michael A.; Ware, Lorraine B.
Objective To determine if levels of soluble intercellular adhesion molecule-1 (sICAM-1), a marker of alveolar epithelial and endothelial injury, differ in patients with hydrostatic pulmonary edema and acute lung injury (ALI) and are associated with clinical outcomes in patients with ALI. Design, setting, and participants Measurement of sICAM-1 levels in (1) plasma and edema fluid from 67 patients with either hydrostatic pulmonary edema or ALI enrolled in an observational, prospective single center study, and (2) in plasma from 778 patients with ALI enrolled in a large multi-center randomized controlled trial of ventilator strategy. Results In the single-center study, levels of sICAM-1 were significantly higher in both edema fluid and plasma (median 938 and 545 ng/ml, respectively) from ALI patients compared to hydrostatic edema patients (median 384 and 177 ng/ml, P < 0.03 for both comparisons). In the multi-center study, higher plasma sICAM-1 levels were associated with poor clinical outcomes in both unadjusted and multivariable models. Subjects with ALI whose plasma sICAM-1 levels increased over the first 3 days of the study had a higher risk of death, after adjusting for other important predictors of outcome (odds ratio 1.48; 95% CI 1.03¢2.12, P = 0.03). Conclusions Both plasma and edema fluid levels of sICAM-1 are higher in patients with ALI than in patients with hydrostatic pulmonary edema. Higher plasma sICAM-1 levels and increasing sICAM-1 levels over time are associated with poor clinical outcomes in ALI. Measurement of sICAM-1 levels may be useful for identifying patients at highest risk of poor outcomes from ALI. PMID:18670758
Prognostic value of plasma soluble intercellular adhesion molecule-1 and endothelin-1 concentration in patients with chronic congestive heart failure
Takayoshi Tsutamoto; Tomoko Hisanaga; Daisuke Fukai; Atsuyuki Wada; Yukiharu Maeda; Keiko Maeda; Masahiko Kinoshita
We tested the hypothesis that plasma endothelin-1 (ET-1) and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with congestive heart failure (CHF) are related to subsequent survival, and assessed whether the measurements of these substances provide additional prognostic information to that obtained from clinical and biochemical variables previously known to be associated with high mortality. Plasma levels of sICAM-1 and ET-1
Soluble intercellular adhesion molecule-1 and clinical outcomes in patients with acute lung injury
Carolyn S. Calfee; Mark D. Eisner; Polly E. Parsons; B. Taylor Thompson; Edward R. Conner Jr; Michael A. Matthay; Lorraine B. Ware
ObjectiveĀĀTo determine if levels of soluble intercellular adhesion molecule-1 (sICAM-1), a marker of alveolar epithelial and endothelial\\u000a injury, differ in patients with hydrostatic pulmonary edema and acute lung injury (ALI) and are associated with clinical outcomes\\u000a in patients with ALI.\\u000a \\u000a \\u000a \\u000a Design, setting, and participantsĀĀMeasurement of sICAM-1 levels in (1) plasma and edema fluid from 67 patients with either hydrostatic pulmonary
Measurement of Human Intercellular Adhesion Molecule 1 in the Blood Is Useful for Predicting the Occurrence of Hepatocellular Carcinomas from Chronic Hepatitis C and Liver Cirrhosis
Mitsuhiko Moriyama; Hiroshi Matsumura; Jiro Shioda; Hiroshi Aoki; Hitomi Nakamura; Yasuo Arakawa; Kazushige Nirei; Hiroaki Yamagami; Miki Kaneko; Naohide Tanaka; Yasuyuki Arakawa
Objective: We measured the concentrations of serum intercellular adhesion molecule 1 (sICAM-1) in patients with C-viral chronic liver diseases and started prospective studies immediately thereafter, in order to determine whether the concentration of sICAM-1 is useful for predicting the occurrence of hepatocellular carcinoma (HCC) following C-viral chronic hepatitis (CH) and liver cirrhosis (LC). Methods: We studied 74 patients with CH,
Hepatic allograft rejection is associated with increased levels of soluble intercellular adhesion molecule-1.
Ninova, D; Krom, R A; Wiesner, R H
Intercellular adhesion molecule-1 (ICAM-1) is an adhesion molecule from the immunoglobulin super family that is recognized to be an important factor in the multistep process of cell transendothelial migration and lymphocyte adhesion during antigen recognition and effector cytolysis, mechanisms known to be involved in the pathogenesis of hepatic allograft rejection. A soluble form of ICAM-1 (sICAM-1) can be shed into the circulation. In this study, we examined the levels of sICAM-1 in hepatic allograft recipients as possible markers of cellular rejection and the presence of cytomegalovirus (CMV) hepatitis. We studied three groups of patients, including eight patients with histologically documented cellular rejection, five patients with histologically documented CMV hepatitis, and a liver transplantation control population. Serum samples were obtained at the following times: baseline (1 to 3 days after transplantation), at time of diagnosis of cellular rejection, and at time of diagnosis of CMV hepatitis and 1 week after treatment of rejection episodes. The levels of sICAM-1 were measured using an established commercial enzyme immunoassay with a sensitivity of 0.3 ng/mL. We found that serum levels of sICAM-1 were significantly increased in liver transplant recipients who were experiencing hepatic allograft rejection but were unchanged in patients with CMV hepatitis or the time-matched liver transplant controls. Serum levels of sICAM-1 decreased significantly after successful treatment of the rejection episode with bolus corticosteroid therapy. We conclude that serum levels of sICAM-1 may be useful in monitoring the occurrence of rejection and the response to antirejection therapy in liver transplant recipients. PMID:9346585
Quantitative trait locus on Chromosome 19 for circulating levels of intercellular adhesion molecule-1 in Mexican Americans
Jack W. Kent; Michael C. Mahaney; Anthony G. Comuzzie; Harald H. H. G÷ring; Laura Almasy; Thomas D. Dyer; Shelley A. Cole; Jean W. MacCluer; John Blangero
Circulating soluble intercellular adhesion molecule-1 (sICAM-1) is a biochemical marker of inflammation. We performed variance-components-based quantitative genetic analyses in SOLAR of sICAM-1 in 1170 individuals from Mexican American families in the San Antonio Family Heart Study. The trait is heritable (h2=0.50▒0.06, P<10?6). Multipoint linkage analysis using a ?10-cM microsatellite map revealed a region on Chromosome 19p near marker D19S586 showing
Arginase levels and their association with Th17-related cytokines, soluble adhesion molecules (sICAM-1 and sVCAM-1) and hemolysis markers among steady-state sickle cell anemia patients
Vilas-Boas, Wendell; Cerqueira, Bruno A. V.; Zanette, Angela M. D.; Reis, Mitermayer G.; Barral-Netto, Manoel
Sickle cell anemia (SCA) is characterized by a marked endothelial dysfunction, owing to many factors. Arginine metabolism can be related to the inflammatory chronic state presented by patients, playing a key role in their clinical outcome and vascular endothelium. We investigated the serum arginase levels in 50 SCA patients (22 men and 28 women, mean age of 17?▒?10.5Āyears) and 28 healthy controls. Serum arginase levels were associated with biochemical hemolysis markers and cytokines involved in Th17 response, as well as levels of soluble intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1). Arginase concentrations were higher in SCA patients, compared with controls (p?=?0.005), and were significantly and positively associated with total bilirubin (p?=?0.004), indirect bilirubin (p?=?0.04), and aspartate aminotransferase (AST; p?=?0.039) in the SCA patient group. Moreover, arginase was significantly and positively associated with transforming growth factor-beta (TGF-beta; p?=?0.008) among SCA patients. sICAM-1 was significantly and positively associated to reticulocytes (p?=?0.014) and AST (p?=?0.04). sVCAM-1 was likewise associated with lactate dehydrogenase (p?=?0.03). These data suggest a new insight into arginase metabolism, as we show here a shift in arginine catabolism, where TGF-beta may induces the arginase pathway instead of the nitric oxide pathway and a possible involvement of the vascular activation and the serum arginase in chronic hemolysis among SCA patients. Additional studies should be carried out in order to investigate the mechanisms by which TGF-beta participates in the metabolism of arginase in SCA patients. PMID:20405289
The clinical usefulness of assessing the concentration of cell adhesion molecules sVCAM-1 and sICAM-1 in the serum of women with primary breast cancer
Baszczuk, Aleksandra; Kopczy?ski, Zygmunt; Nowak, Adrianna; Grodecka-Gazdecka, Sylwia
Aim of the study Assessment of the concentrations of the soluble forms of the cell adhesion molecules sVCAM-1 and sICAM-1 in serum of female breast cancer patients. These concentrations were assessed in relation to factors such as: age, clinical stage of disease, histological grade of malignancy, the status of the local axillary lymph nodes, and the size of the primary tumour. Material and methods A total of 103 patients with primary breast cancer, aged 29 to 89 years, were investigated. The control group consisted of 40 healthy women. The concentration of sVCAM-1 and sICAM-1 was assessed using an enzyme-linked immunosorbent assay (ELISA). Results The results of the study suggest that the level of sVCAM-1 and sICAM-1 in the serum of women with breast cancer was significantly higher than that seen in the serum of healthy women. A relationship between the level of adhesion molecules and the stage of clinical disease advancement was discovered. There was a correlation between the increasing concentrations of sVCAM-1 and sICAM-1 and with the aggressiveness of the disease. Significant differences were also found in the group of women with metastases to the axillary lymph nodes and women with no metastasis. Similar correlations were found between sVCAM-1 and sICAM-1 levels and the size of primary tumour. Conclusions The results obtained suggest that the assessment of the soluble forms of sVCAM-1 and sICAM-1 may be useful indicators in the assessment of the clinical advancement of breast cancer. PMID:25258583
A meal rich in oleic acid beneficially modulates postprandial sICAM-1 and sVCAM-1 in normotensive and hypertensive hypertriglyceridemic subjects.
Pacheco, Yolanda M; L¾pez, Sergio; Berm·dez, Beatriz; Abia, RocĒo; Villar, Josķ; Muriana, Francisco J G
This study investigated whether subjects with permanent activated endothelium have altered soluble forms of intercellular adhesion molecule 1 (sICAM-1) and vascular cell adhesion molecule 1 (sVCAM-1) postprandial response to a high-fat meal and whether this phenomenon is modulated by the nature of dietary fats. Twenty-eight hypertriglyceridemic (14 normotensives and 14 hypertensives) and 14 healthy male subjects were placed in a randomized and crossover design on diets enriched in refined olive oil (ROO) or high-palmitic sunflower oil (HPSO) for a 1-week lead-in period. Thereafter, subjects ate the corresponding fat-rich meal as a breakfast and underwent sampling hourly for 8 h. Plasma triglycerides (TG), sICAM-1 and sVCAM-1 were assayed. sICAM-1 and sVCAM-1 postprandial peak levels were significantly higher and occurred later in hypertriglyceridemic subjects (all P<.001) compared with healthy subjects. ROO meal resulted in smaller areas under the curve for sICAM-1 and sVCAM-1 in hypertriglyceridemic (normotensive and hypertensive) and healthy subjects compared to HPSO meal. Hypertension did not aggravate the postprandial response of TG, sICAM-1 and sVCAM-1. We conclude that the challenge of a meal with ROO appears to have a significant postprandial benefit on sICAM-1 and sVCAM-1 as surrogate markers of endothelial activation and vascular inflammation in healthy and more importantly in hypertriglyceridemic (normotensive and hypertensive) subjects. PMID:17651961
Intercellular adhesion molecule-1 is a regulator of blood¢testis barrier function
Xiao, Xiang; Cheng, C. Yan; Mruk, Dolores D.
Summary The mechanism underlying the movement of preleptotene/leptotene spermatocytes across the blood¢testis barrier (BTB) during spermatogenesis is not well understood largely owing to the fact that the BTB, unlike most other blood¢tissue barriers, is composed of several co-existing and co-functioning junction types. In the present study, we show that intercellular adhesion molecule-1 [ICAM-1, a Sertoli and germ cell adhesion protein having five immunoglobulin (Ig)-like domains, in addition to transmembrane and cytoplasmic domains] is a regulator of BTB integrity. Initial experiments showed ICAM-1 to co-immunoprecipitate and co-localize with tight junction and basal ectoplasmic specialization proteins such as occludin and N-cadherin, which contribute to BTB function. More importantly, overexpression of ICAM-1 in Sertoli cells in vitro enhanced barrier function when monitored by transepithelial electrical resistance measurements, illustrating that ICAM-1-mediated adhesion can promote BTB integrity. On the other hand, overexpression of a truncated form of ICAM-1 that consisted only of the five Ig-like domains (sICAM-1; this form of ICAM-1 is known to be secreted) elicited an opposite effect when Sertoli cell barrier function was found to be perturbed in vitro; in this case, sICAM-1 overexpression resulted in the downregulation of several BTB constituent proteins, which was probably mediated by Pyk2/p-Pyk2-Y402 and c-Src/p-Src-Y530. These findings were expanded to the in vivo level when BTB function was found to be disrupted following sICAM-1 overexpression. These data illustrate the existence of a unique mechanism in the mammalian testis where ICAM-1 can either positively or negatively regulate BTB function. PMID:22976294
Crevicular fluid levels of interleukin-8, interleukin-17 and soluble intercellular adhesion molecule-1 after regenerative periodontal therapy
Erdemir, Ebru Olgun; Hendek, Meltem Karsiyaka; Keceli, H. Gencay; Apan, Teoman Z.
Objective: The aim of this study is to evaluate the influence of regenerative periodontal therapy on clinical parameters and interleukin-8 (IL-8), IL-17 and soluble intercellular adhesion molecule-1 (sICAM-1) levels in gingival crevicular fluid (GCF) of subjects with chronic periodontitis (CP). Materials and Methods: Fifteen patients received demineralized freeze-dried bone allograft (DFDBA) surgically to the site of infrabony defect. Clinical periodontal indices were recorded, and GCF samples were collected at baseline and at the 6th and the 9th month after the surgery. Results: Except plaque index, all clinical parameters improved following surgery (P < 0.05). The volume of GCF diminished from baseline to follow-up periods (P < 0.05). However, no effect was observed on the total amount of IL-8, IL-17 and sICAM-1 in GCF. Conclusion: DFDBA improved clinical outcome in CP subjects and was effective on decreasing the volume of GCF, but no effect was determined on IL-8, IL-17 and sICAM-1. Findings did not indicate a direct relationship between biochemical parameters and periodontal healing after demineralized freeze-dried bone grafting. PMID:25713486
Effect of corticosteroids on release of RANTES and sICAM-1 from cultured human bronchial epithelial cells, induced by TNF-?
J. H. Wang; J. L. Devalia; R. J. Sapsford; R. J. Davies
We have recently demonstrated that human bronchial epithelial cells can synthesise and release several inflammatory mediators, including the factor regulated on activation, normal T-cell expressed and secreted (RANTES) and sol- uble intercellular adhesion molecule-1 (sICAM-1), which influence the activity of eosinophils, and may, therefore play a role in the aetiology of asthma. In this study we investigated whether corticosteroids could
Eosinophils Adhere to Vascular Cell Adhesion Molecule-1 via Podosomes
Mosher, Deane F.
counter-receptors on the surface of cultured endothelial (Received in original form March 19, 2004Eosinophils Adhere to Vascular Cell Adhesion Molecule-1 via Podosomes Mats W. Johansson, Ming H of Medicine and Biomolecular Chemistry, University of Wisconsin, Madison, Wisconsin Vascular cell adhesion
Mesangial cell accessory functions: Mediation by intercellular adhesion molecule-1
Daniel C Brennan; Anthony M Jevnikar; Fumio Takei; Vicki E Reubin-Kelley
Mesangial cell accessory functions: Mediation by intercellular adhesion molecule-1. Mesangial cell (MC) proliferation is an early pathologic alteration characteristic of many forms of immune mediated glomerulonephritis. The intracapillary position, contractile capacity, and production of cytokines and other inflammatory molecules place MC in a pivotal position to initiate, mediate, and direct glomerular damage. We as well as others have noted increased
Intercellular adhesion molecule-1 gene polymorphisms in Behcet's disease
D. H. Verity; R. W. Vaughan; E. Kondeatis; W. Madanat; H. Zureikat; F. Fayyad; J. E. Marr; C. A. Kanawati; G. R. Wallace; M. R. Stanford
It was recently suggested that genetic factors could play a major role in the development of Graves' disease (GD). The aim of the present study was to evaluate the frequency of the c.721G3 A polymorphism and the c.1405A3 G polymorphism of the intercellular adhesion molecule 1 (ICAM-1) gene in sub- jects with GD compared with that in healthy controls, because
Increased Plasma and Endothelial Cell Expression of Chemokines and Adhesion Molecules in Chronic Kidney Disease
A. E. M. Stinghen; S. M. Gonńalves; E. G. Martines; L. S. Nakao; M. C. Riella; C. A. Aita; R. Pecoits-Filho
Chemokines and adhesion molecules are involved in early events of atherogenesis. In the present study, we investigated the effects of the uremic milieu on the expression of monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), soluble vascular adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1) and their relationship to cardiovascular status. Plasma samples were obtained from patients in different stages of
Carbohydrate ligands for endothelial - Leukocyte adhesion molecule 1
Tiemeyer, M.; Swiedler, S.J.; Ishihara, Masayuki; Moreland, M.; Schweingruber, H.; Hirtzer, P.; Brandley, B.K. (Glycomed, Inc., Alameda, CA (United States))
The acute inflammatory response requires that circulating leukocytes bind to and penetrate the vascular wall to access the site of injury. Several receptors have been implicated in this interaction, including a family of putative carbohydrate-binding proteins. The authors report here the identification of an endogenous carbohydrate ligand for one of these receptors, endothelial-leukocyte adhesion molecule 1 (ELAM-1). Radiolabeled COS cells transfected with a plasmid containing the cDNA for ELAM-1 were used as probes to screen glycolipids extracted from human leukocytes. COS cells transfected with this plasmid adhered to a subset of sialylated glycolipids resolved on TLC plates or adsorbed on polyvinyl chloride microtiter wells. Adhesion to these glycolipids required calcium but was not inhibited by heparin, chondroitin sulfate, keratan sulfate, or yeast phosphomannan. Monosaccharide composition, linkage analysis, and fast atom bombardment mass spectrometry of the glycolipids indicate that the ligands for ELAM-1 are terminally sialylated lactosylceramides with a variable number of N-acetyllactosamine repeats and at least one fucosylated N-acetylglucosamine residue.
Increased soluble vascular cell adhesion molecule-1 plasma levels and soluble intercellular adhesion molecule-1 during antiretroviral therapy interruption and retention of elevated soluble vascular cellular adhesion molecule-1 levels following resumption of antiretroviral therapy
Papasavvas, Emmanouil; Azzoni, Livio; Pistilli, Maxwell; Hancock, Aidan; Reynolds, Griffin; Gallo, Cecile; Ondercin, Joe; Kostman, Jay R.; Mounzer, Karam; Shull, Jane; Montaner, Luis J.
Objective We investigated the effect of short viremic episodes on soluble markers associated with endothelial stress and cardiovascular disease risk in chronically HIV-1-infected patients followed during continuous antiretroviral therapy, antiretroviral therapy interruption and antiretroviral therapy resumption. Design and methods We assessed changes in plasma levels of von Willebrand factor, soluble vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 by enzyme-linked immunosorbent assay, as well as T-cell activation (CD8+/CD38+, CD8+/HLA-DR+ and CD3+/CD95+) by flow cytometry, in 36 chronically HIV-1-infected patients participating in a randomized study. Patients were divided into the following three groups: a, on continuous antiretroviral therapy; b, on a 6-week antiretroviral therapy interruption; or c, on antiretroviral therapy interruption extended to the achievement of viral set point. Results Although all measurements remained stable over a 40-week follow-up on antiretroviral therapy, plasma levels of soluble vascular cell adhesion molecule-1 (P < 0.0001) and soluble intercellular adhesion molecule-1 (P = 0.003) increased during treatment interruption in correlation with viral rebound and T-cell activation. No significant changes in von Willebrand factor were observed in any of the groups. After resuming antiretroviral therapy, soluble vascular cell adhesion molecule-1 levels remained elevated even after achievement of viral suppression to less than 50 copies/ml. Conclusion The prompt rise in plasma soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-1 upon viral rebound suggests an acute increase in endothelial stress upon treatment interruption, which may persists after viral resuppression of virus. Thus, viral replication during short-term treatment interruption may increase the overall cardiovascular risk during and beyond treatment interruption. PMID:18525261
A prospective study of the sensitivity, specificity and diagnostic performance of soluble intercellular adhesion molecule 1, highly sensitive C-reactive protein, soluble E-selectin and serum amyloid A in the diagnosis of neonatal infection
Background Diagnosis of neonatal infection is difficult, because of it's non-specific clinical presentation and the lack of reliable diagnostic tests. The purpose of this study was to examine the potential diagnostic value of serum soluble intercellular adhesion molecule-1 (sICAM-1), soluble E-selectin (sE-selectin), highly sensitive C-reactive protein (hsCRP) and serum amyloid A (SAA) measurements, both individually and in combination in the setting of a neonatal intensive care unit. Methods 219 consecutive serum samples were taken from 149 infants undergoing sepsis work up in a neonatal intensive care unit. Clinical diagnosis was established in a prospective manner, blind to the results of the study measurements. Infants were classified by an experienced paediatrician as infected or not-infected, one week after presentation. Classification was based on clinical presentation, routine laboratory and radiological investigations and response to therapy. The infected group were sub-classified as (a) culture positive infection or (b) culture negative infection. sICAM-1, sE-selectin, hsCRP and SAA levels were determined from stored serum samples after diagnosis was established. Further sub-group analysis of results was undertaken according to early or late onset of infection and preterm or term status. Statistical analysis utilised Mann Whitney U test and ROC curve analysis. Results There were significantly increased serum levels of sICAM-1, hsCRP, E selectin (p < 0.001) and SAA (p = 0.004) in infected infants compared with non-infected. ROC curve analysis indicated area under the curve values of 0.79 (sICAM-1), 0.73 (hsCRP), 0.72 (sE-selectin) and 0.61 (SAA). ROC curve analysis also defined optimum diagnostic cut-off levels for each measurement. The performance characteristics of sICAM-1, hsCRP and sE-selectin included a high negative predictive value (NPV) for culture positive infection and this was enhanced by combination of all 4 measurements. Clinical subgroup analysis suggested particularly high NPV for early onset symptoms, however further studies are required to elucidate this finding. Conclusions All four study measurements demonstrated some diagnostic value for neonatal infection however sICAM-1, hsCRP and sE-selectin demonstrated the highest NPV individually. The optimum diagnostic cut off level for hsCRP measurement in this study was much lower than currently used in routine clinical practice. Use of a combination of measurements enhanced diagnostic performance, demonstrating sensitivity of 90.3% and NPV of 91.3%. This study suggests there may be value in use of several of these markers, individually and in combination to assist in excluding neonatal infection. Further work is needed to confirm a specific role in the exclusion of early onset infection. PMID:20398379
Angiogenesis mediated by soluble forms of E-selectin and vascular cell adhesion molecule-1
NASA Astrophysics Data System (ADS)
Koch, Alisa E.; Halloran, Margaret M.; Haskell, Catherine J.; Shah, Manisha R.; Polverini, Peter J.
ENDOTHELIAL adhesion molecules facilitate the entry of leukocytes into inflamed tissues. This in turn promotes neovascularization, a process central to the progression of rheumatoid arthritis, tumour growth and wound repair1. Here we test the hypothesis that soluble endothelial adhesion molecules promote angiogenesis2ßż-4. Human recombinant soluble E-selectin and soluble vascular cell adhesion molecule-1 induced chemotaxis of human endothelial cells in vitro and were angiogenic in rat cornea. Soluble E-selectin acted on endothelial cells in part through a sialyl Lewis-X-dependent mechanism, while soluble vascular cell adhesion molecule-1 acted on endothelial cells in part through a very late antigen (VLA)-4 dependent mechanism. The chemotactic activity of rheumatoid synovial fluid for endothelial cells, and also its angiogenic activity, were blocked by antibodies to either soluble E-selectin or soluble vascular cell adhesion molecule-1. These results suggest a novel function for soluble endothelial adhesion molecules as mediators of angiogenesis.
Vascular cell adhesion molecule-1 (VCAM-1) expression in murine lupus nephritis
Rudolf P Wuthrich; Tracey L Snyder
Vascular cell adhesion molecule-1 (VCAM-1) expression in murine lupus nephritis. Vascular cell adhesion molecule-1 (VCAM-1) is a cell surface protein which mediates adherence of inflammatory cells to target cells by binding with the ?1-integrin ligand Very Late Antigen-4 (VLA-4) on leukocytes. The expression of VCAM-1 was investigated in a murine model of lupus nephritis, the autoimmune MRL\\/lpr mouse. Compared with
Adiponectin Enhances Intercellular Adhesion Molecule-1 Expression and Promotes Monocyte Adhesion in Human Synovial Fibroblasts
Chen, Hsien-Te; Tsou, Hsi-Kai; Chen, Jui-Chieh; Shih, James Meng-Kun; Chen, Yen-Jen; Tang, Chih-Hsin
Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes and is involved in energy homeostasis. Adiponectin expression is significantly high in the synovial fluid of patients with osteoarthritis (OA). Intercellular adhesion molecule-1 (ICAM-1) is an important adhesion molecule that mediates monocyte adhesion and infiltration during OA pathogenesis. Adiponectin-induced expression of ICAM-1 in human OA synovial fibroblasts (OASFs) was examined by using qPCR, flow cytometry and western blotting. The intracellular signaling pathways were investigated by pretreated with inhibitors or transfection with siRNA. The monocyte THP-1 cell line was used for an adhesion assay with OASFs. Stimulation of OASFs with adiponectin induced ICAM-1 expression. Pretreatment with AMP-activated protein kinase (AMPK) inhibitors (AraA and compound C) or transfection with siRNA against AMPK?1 and two AMPK upstream activator- liver kinase B1 (LKB1) and calmodulin-dependent protein kinase II (CaMKII) diminished the adiponectin-induced ICAM-1 expression. Stimulation of OASFs with adiponectin increased phosphorylation of LKB1, CaMKII, AMPK, and c-Jun, resulting in c-Jun binding to AP-1 element of ICAM-1 promoter. In addition, adiponectin-induced activation of the LKB1/CaMKII, AMPK, and AP-1 pathway increased the adhesion of monocytes to the OASF monolayer. Our results suggest that adiponectin increases ICAM-1 expression in human OASFs via the LKB1/CaMKII, AMPK, c-Jun, and AP-1 signaling pathway. Adiponectin-induced ICAM-1 expression promoted the adhesion of monocytes to human OASFs. These findings may provide a better understanding of the pathogenesis of OA and can utilize this knowledge to design a new therapeutic strategy. PMID:24667577
Intercellular Adhesion Molecule1 (ICAM-1) in the Pathogenesis of Asthma
Craig D. Wesgner; Robert H. Gundel; Patricia Reilly; Nancy Haynes; L. Gordon Letts; Robert Rothlein
Airway eosinophilia, epithelial desquamation, and hyperresponsiveness are characteristics of the airway inflammation underlying bronchial asthma. The contribution of intercellular adhesion molecule-1 (ICAM-1) to eosinophil migration and airway responsiveness was studied. ICAM-1 partially mediated eosinophil adhesion to endothelium in vitro and was upregulated on inflamed bronchial endothelium in vivo. ICAM-1 expression was also upregulated on inflamed airway epithelium in vitro and
Correlation between clinical features and circulating levels of soluble intercellular adhesion molecule-1 in Hodgkin's disease.
Nadali, G; Vinante, F; Rigo, A; Tecchio, C; Morosato, L; Zanolin, E; Perona, G; Chilosi, M; Pizzolo, G
Previous reports have suggested soluble intercellular adhesion molecule-1 as a marker of disease activity in Hodgkin's disease. In the present study we investigated serum levels of intercellular adhesion molecule-1 at diagnosis in 104 patients with Hodgkin's disease and in 77 of these patients following the achievement of complete remission (within 12 months of diagnosis). Mean serum levels at diagnosis were significantly higher in patients than in controls (P < 0.0001) and were related to advanced stages of disease (P = < 0.0001), presence of "B" symptoms (P < 0.0001), abnormality of laboratory indexes (P < 0.0001), erythrocyte sedimentation rate values (r = 0.41, P < 0.0001) and serum levels of soluble interleukin-2 receptor alpha chain (r = 0.51, P < 0.0001). Mean values in complete remission were significantly lower than at diagnosis (P = 0.003). Lower mean values at diagnosis were detected in 30 patients with advanced disease who attained complete remission, compared with 6 patients who failed to attain complete remission with standard treatment. We conclude that in Hodgkin's disease, high serum levels of soluble intercellular adhesion molecule-1 are detectable at presentation and strictly correlate with some clinical features. Response to treatment is paralleled by reduced serum levels. Larger prospective studies are needed to evaluate the possible prognostic significance of serum levels of soluble intercellular adhesion molecule-1 at diagnosis. PMID:7663010
Elevated Serum Vascular Cell Adhesion Molecule-1 Is Associated with Septic Encephalopathy in Adult Community-Onset Severe Sepsis Patients
Su, Chih-Min; Cheng, Hsien-Hung; Tsai, Tsung-Cheng; Hsiao, Sheng-Yuan; Tsai, Nai-Wen; Chang, Wen-Neng; Lin, Wei-Che; Cheng, Ben-Chung; Chang, Ya-Ting; Chiang, Yi-Fang; Kung, Chia-Te; Lu, Cheng-Hsien
Background and Aim. Septic encephalopathy (SE) is a common complication of severe sepsis. Increased concentrations of circulating soluble adhesion molecules are reported in septic patients. This study aimed to determine whether serum adhesion molecules are associated with SE. Methods. Seventy nontraumatic, nonsurgical adult patients with severe sepsis admitted through ER were evaluated. Serum adhesion molecules were assessed for their relationship with SE, and compared with other clinical predictors and biomarkers. Results. Twenty-three (32.8%) patients had SE. SE group had higher in-hospital mortality (40% versus 11%, P = 0.009) and their sVCAM-1, sICAM-1, and lactate levels on admission were also higher than non-SE group. By stepwise logistic regression model, sVCAM-1, age, and maximum 24-hours SOFA score were independently associated with septic encephalopathy. The AUC analysis of ROC curve of different biomarkers showed that sVCAM-1 is better to predict SE. The sVCAM-1 levels in the SE group were significantly higher than those of the non-SE group at three time periods (Days 1, 4, and 7). Conclusions. Septic encephalopathy implies higher mortality in nontraumatic, nonsurgical patients with severe sepsis. VCAM-1 level on presentation is a more powerful predictor of SE in these patients than lactate concentration and other adhesion molecules on admission. PMID:24883317
Effect of Atorvastatin and Pioglitazone on Plasma Levels of Adhesion Molecules in Non-Diabetic Patients With Hypertension or Stable Angina or Both
Pattan, Vishwanath; Seth, Sandeep; Jehangir, Waqas; Bhargava, Balram; Maulik, Subir Kumar
Background It was to study the effect of atorvastatin, pioglitazone and their combination on plasma levels of adhesion molecules in patients with hypertension or stable angina or both. Methods It was an open-label, randomized parallel-group study. Forty-five atorvastatin-naive patients with hypertension or stable angina or both, were randomized to receive either atorvastatin (19 patients; 10 mg OD for 12 weeks) or pioglitazone (26 patients; 30 mg OD for 12 weeks). Another group of 30 patients who were already on atorvastatin were put on add-on pioglitazone therapy (pioglitazone (15 mg OD) + atorvastatin (10 mg OD) for 12 weeks). Plasma high-sensitivity C-reactive protein (hsCRP), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) levels were measured at baseline and after 12 weeks of therapy. Results Atorvastatin monotherapy significantly reduced plasma sICAM-1, but pioglitazone monotherapy did not produce any significant effect. Addition of pioglitazone in patients already receiving atorvastatin also significantly reduced plasma sICAM-1 level. However, there was no significant change in plasma hsCRP and sVCAM-1 levels in any of the groups after 12 weeks of therapy. Conclusion There is therapeutic advantage of combining pioglitazone and atorvastatin on plasma sICAM-1 levels. PMID:26124907
Concentration of soluble adhesion molecules in cerebrospinal fluid and serum of epilepsy patients.
Luo, Jing; Wang, Wei; Xi, Zhiqin; Dan, Chen; Wang, Liang; Xiao, Zheng; Wang, Xuefeng
Mounting evidence supports the involvement of brain inflammation and the associated blood-brain barrier damage from which spontaneous and recurrent seizures originate. Detection of the soluble form of adhesion molecules (AM) has also been proven to predict outcomes in central nervous system (CNS) disorders. A recent study has shown that expression of AM in brain vessels was upregulated 24Āh after kainic acid (KA) induced seizures. The aim of the present study was to investigate soluble AM levels in the cerebrospinal fluid (CSF) and serum of epilepsy patients. Paired CSF and serum samples were analyzed by sandwich enzyme-linked immunosorbent assay (ELISA) to determine the concentrations of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1). Increased serum concentrations of sICAM-1 were present in epileptic patients (41 localization-related of unknown etiology, 19 idiopathic generalized). Serum sICAM-1 level in drug-refractory epilepsy was elevated as compared to new diagnosis epilepsy and drug-responsive epilepsy. CSF sVCAM-1 and serum sVCAM-1 concentrations in the epilepsy group were higher as compared to the neurosis group. Moreover, CSF sVCAM-1 and serum sVCAM-1 concentrations in drug-refractory epilepsy were raised as compared to drug-responsive epilepsy and new diagnosis epilepsy. However, there were no significant differences in concentrations of CSF sICAM-1 between the epilepsy and neurosis groups. Our results suggest that sVCAM-1 and sICAM-1 could play an important role in the drug-refractory epilepsy. PMID:25001004
Targeting sites of inflammation: intercellular adhesion molecule-1 as a target for novel inflammatory therapies
Hua, Susan
Targeted drug delivery to sites of inflammation will provide effective, precise, and safe therapeutic interventions for treatment of diverse disease conditions, by limiting toxic side effects and/or increasing drug action. Disease-site targeting is believed to play a major role in the enhanced efficacy observed for a variety of drugs when formulated inside lipid vesicles. This article will focus on the factors and mechanisms involved in drug targeting to sites of inflammation and the importance of cell adhesion molecules, in particular intercellular adhesion molecule-1, in this process. PMID:24109453
Intercellular Adhesion Molecule-1 (ICAM-1) in the Pathogenesis of Asthma
NASA Astrophysics Data System (ADS)
Wesgner, Craig D.; Gundel, Robert H.; Reilly, Patricia; Haynes, Nancy; Letts, L. Gordon; Rothlein, Robert
Airway eosinophilia, epithelial desquamation, and hyperresponsiveness are characteristics of the airway inflammation underlying bronchial asthma. The contribution of intercellular adhesion molecule-1 (ICAM-1) to eosinophil migration and airway responsiveness was studied. ICAM-1 partially mediated eosinophil adhesion to endothelium in vitro and was upregulated on inflamed bronchial endothelium in vivo. ICAM-1 expression was also upregulated on inflamed airway epithelium in vitro and in vivo. In a primate model of asthma, a monoclonal antibody to ICAM-1 attenuated airway eosinophilia and hyperresponsiveness. Thus, antagonism of ICAM-1 may provide a therapeutic approach to reducing airway inflammation, hyperresponsiveness, and asthma symptoms.
Expression of intercellular adhesion molecule 1 (ICAM-1, CD54) in colonic epithelial cells
W Dippold; B Wittig; W Schwaeble; W Mayet; K H Meyer zum B³schenfelde
The expression of intercellular adhesion molecule-1 (ICAM-1, CD54) was examined in 16 surgically removed colonic tumours and two colonic carcinoma cell lines. Immunohistochemistry showed a varying percentage of ICAM-1 positive colonic carcinoma cells in 9\\/16 tissue specimens, while normal colonic tissue (apart from a slight reactivity of endothelial cells) was not stained. The presence of the ICAM-1 molecule on the
Junctional Adhesion Molecule 1 Is a Functional Receptor for Feline Calicivirus
Akiko Makino; Masayuki Shimojima; Takayuki Miyazawa; Kentaro Kato; Yukinobu Tohya; Hiroomi Akashi
The life cycle of calicivirus is not fully understood because most of the viruses cannot be propagated in tissue culture cells. We studied the mechanism of calicivirus entry into cells using feline calicivirus (FCV), a cultivable calicivirus. From the cDNA library of Crandell-Rees feline kidney (CRFK) cells, feline junctional adhesion molecule 1 (JAM-1), an immunoglobulin-like protein present in tight junctions,
Expression of Intercellular Adhesion Molecule1 Is Regulated by the Actin Network in Epidermoid Carcinoma Cells
Johannes Norgauer; Frauke Bartels; Udo G÷hring; Erwin Sch÷pf; Peter Gebicke-Haerter; Eckhard Kownatzki; Jean Krutmann
Expression of the cell surface protein intercellular adhesion molecule-1 (ICAM-1) is a prerequisite for the interaction of a large variety of cells with leukocytes. Constitutive expression of ICAM-1 in human epidermoid carcinoma cells is low, but is inducible through inflammatory cytokines including interferon ? (INF?). Disruption of the actin cytoskeleton with dehydrocytochalasin B (CB) increased constitutive and potentiated INF?-induced ICAM-1
Induction of Intercellular Adhesion Molecule 1 (ICAM-1) Expression in Normal Human Eosinophils by Inflammatory Cytokines
Wolfgang Czech; Jean Krutmann; Anne Budnik; Erwin Sch÷pf; Alexander Kapp
Intercellular adhesion molecule-1 (ICAM-1) functions as a ligand for lymphocyte function-associated antigen-1 (LFA-1), and thereby plays a crucial role in mediating cell-cell interactions in inflammatory reactions. Human eosinophils represent important effector cells in allergic skin diseases. To gain more insight into the capacity of eosinophils to physically interact with LFA-1-positive inflammatory leukocytes, in the present study ICAM-1 expression in eosinophils
Effect of pulsed dye laser on intercellular adhesion molecule-1 (ICAM-1) expression after treatment of psoriasis
Mona Soliman; Hesham Zaher; Nabil El Danasouri; Abeer Attia; Waguih Tawfik
BackgroundIntercellular adhesion molecule-1 (ICAM-1) is a member of the immunoglobulin super family of adhesion molecules that plays a role in transendothelial migration and adhesion processes involved in the pathogenesis of psoriasis. Previous studies have demonstrated partial and total clearance of psoriasis by selective photothermolysis of dermal vessels with the pulsed dye laser.
Sophorae radix extract inhibits high glucose-induced vascular cell adhesion molecule-1 up-regulation on endothelial cell line
Kang-Beom Kwon; Eun-Kyung Kim; Jung-Gook Lim; Byung-Cheul Shin; Yung-Sun Song; Eun-A Seo; Ki-Young Ahn; Bong-Keun Song; Do-Gon Ryu
Background: Sophorae radix (SR) has been used for various diseases including atherosclerosis and arrhythmias. Atherosclerosis induced by hyperglycemia is an important factor in the promotion of diabetic complications. An early event in atherosclerosis is the adhesion of monocytes to endothelium via adhesion molecules. Among them, vascular cell adhesion molecule-1 (VCAM-1) expression mediates the binding of monocytes and lymphocytes to vascular
Involvement of oxidative stress and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in inflammatory bowel disease
Tanida, Satoshi; Mizoshita, Tsutomu; Mizushima, Takashi; Sasaki, Makoto; Shimura, Takaya; Kamiya, Takeshi; Kataoka, Hiromi; Joh, Takashi
The pathophysiology of inflammatory bowel disease involves excessive immune effects of inflammatory cells against gut microbes. In genetically predisposed individuals, these effects are considered to contribute to the initiation and perpetuation of mucosal injury. Oxidative stress is a fundamental tissue-destructive mechanisms that can occur due to the reactive oxygen species and reactive nitrogen metabolites which are released in abundance from numerous inflammatory cells that have extravasated from lymphatics and blood vessels to the lamina propria. This extravasation is mediated by interactions between adhesion molecules including mucosal addressin cell adhesion molecule-1 and vascular cell adhesion molecule-1 on the surface of lymphocytes or neutrophils and their ligands on endothelial cells. Thus, reactive oxygen species and adhesion molecules play an important role in the development of inflammatory bowel disease. The present review focuses on the involvement of oxidative stress and adhesion molecules, in particular mucosal addressin cell adhesion molecule-1, in inflammatory bowel disease. PMID:21373262
Intercellular adhesion molecule-1 (ICAM-1) in cellular immune reactions in the human central nervous system.
Sobel, R. A.; Mitchell, M. E.; Fondren, G.
Cryostat sections of human central nervous system (CNS) tissue samples from 10 cases of multiple sclerosis (MS), 11 cases with inflammation and necrosis, and 24 normal controls were immunostained with antibodies to intercellular adhesion molecule-1 (ICAM-1) and its integrin ligand lymphocyte function-associated molecule-1 (LFA-1). In 18 controls, small numbers of CNS microvessels were ICAM-1-positive. There were more numerous ICAM-1-positive vessels in active MS plaque edges, viral encephalitis lesions, infarcts, and in six controls. Within active MS plaques and in viral infections, mononuclear cells and some glia also were ICAM-1-positive. Mononuclear but not CNS resident cells were LFA-1-positive. Thus, CNS vessel ICAM-1 expression is variable in amount in postmortem samples of normal human CNS tissue, may increase early and focally in cellular immune reactions, and, via binding of LFA-1, may promote leukocyte influx into the CNS. Intercellular adhesion molecule-1 expression on parenchymal cells may indicate additional interactions with LFA-1 on inflammatory cells in diverse CNS lesions. Images Figure 1 Figure 5 PMID:1972610
Molecular architecture of a complex between an adhesion protein from the malaria parasite and intracellular adhesion molecule 1.
Brown, Alan; Turner, Louise; Christoffersen, Stig; Andrews, Katrina A; Szestak, Tadge; Zhao, Yuguang; Larsen, Sine; Craig, Alister G; Higgins, Matthew K
The adhesion of Plasmodium falciparum-infected erythrocytes to human tissues or endothelium is central to the pathology caused by the parasite during malaria. It contributes to the avoidance of parasite clearance by the spleen and to the specific pathologies of cerebral and placental malaria. The PfEMP1 family of adhesive proteins is responsible for this sequestration by mediating interactions with diverse human ligands. In addition, as the primary targets of acquired, protective immunity, the PfEMP1s are potential vaccine candidates. PfEMP1s contain large extracellular ectodomains made from CIDR (cysteine-rich interdomain regions) and DBL (Duffy-binding-like) domains and show extensive variation in sequence, size, and domain organization. Here we use biophysical methods to characterize the entire ?300-kDa ectodomain from IT4VAR13, a protein that interacts with the host receptor, intercellular adhesion molecule-1 (ICAM-1). We show through small angle x-ray scattering that IT4VAR13 is rigid, elongated, and monomeric. We also show that it interacts with ICAM-1 through the DBL? domain alone, forming a 1:1 complex. These studies provide a first low resolution structural view of a PfEMP1 ectodomain in complex with its ligand. They show that it combines a modular domain arrangement consisting of individual ligand binding domains, with a defined higher order architecture that exposes the ICAM-1 binding surface to allow adhesion. PMID:23297413
Molecular cloning and adhesive properties of murine platelet/endothelial cell adhesion molecule 1.
Xie, Y; Muller, W A
We describe the isolation and characterization of a functional murine platelet/endothelial cell adhesion molecule (PECAM) 1 cDNA clone from a mouse lung library. At the nucleotide level, the coding sequence of murine PECAM-1 is 73% identical to human PECAM-1, and at the amino acid level, the sequence is 79% homologous to its human counterpart. Southern hybridization reveals that one copy of the gene exists in the mouse genome; Northern hybridization reveals a single mRNA species in mouse lung tissue. COS-7 and mouse L cells transfected with murine PECAM-1 expressed a 130-kDa glycoprotein on their surfaces that reacted with anti-murine PECAM-1 monoclonal antibody and comigrated on SDS/PAGE with human PECAM-1. Stable L-cell transfectants aggregate with each other in a PECAM-dependent, homophilic manner. Images Fig. 3 Fig. 6 PMID:8516303
Thrombin-activated human endothelial cells support monocyte adhesion in vitro following expression of intercellular adhesion molecule-1 (ICAM-1; CD54) and vascular cell adhesion molecule-1 (VCAM-1; CD106).
Kaplanski, G; Marin, V; Fabrigoule, M; Boulay, V; Benoliel, A M; Bongrand, P; Kaplanski, S; Farnarier, C
Thrombin, a central molecule in coagulation, is also involved in inflammation. Notably, thrombin induces endothelial neutrophil adhesion, P- and E-selectin expression, and chemokine production. We show here that thrombin induces expression of intercellular adhesion molecule-1 (ICAM-1; CD54) and vascular cell adhesion molecule-1 (VCAM-1; CD106) on human umbilical vein endothelial cells (HUVECs) associated with increased adhesion of monocytes. Thrombin increased mRNA steady-state levels and expression of ICAM-1 over 24 hours. Thrombin-induced VCAM-1 expression exhibited unusual kinetics, reaching maximum levels after 6 to 12 hours, but decreasing to near baseline after 24 hours. Thrombin activity on HUVECs was mediated through interaction with its specific receptor, because ICAM-1 and VCAM-1 expression were similarly induced by the 14-amino acid thrombin receptor-activating peptide. Thrombin-induced ICAM-1 and VCAM-1 expression was significantly inhibited by hirudin, but not by interleukin-1 receptor antagonist or anti-tumor necrosis factor alpha monoclonal antibody (MoAb). Thrombin-activated HUVECs significantly increased greater numbers of adhering THP-1 macrophagic cells, peripheral blood mononuclear cells, or purified monocytes than unstimulated HUVECs. This adhesion was inhibited by anti-CD18 and anti-CD49d MoAb, demonstrating that thrombin-induced ICAM-1 and VCAM-1 were functional. These results show that, in addition to selectins, thrombin directly induces a cytokine-independent expression of adhesion molecules of the Ig superfamily on HUVECs that may support firm leukocyte attachment during inflammation. PMID:9694714
Soluble intercellular adhesion molecules in human schistosomiasis: correlations with disease severity and decreased responsiveness to egg antigens.
Secor, W E; dos Reis, M G; Ramos, E A; Matos, E P; Reis, E A; do Carmo, T M; Harn, D A
Granuloma formation, the principal pathologic consequence of infection with Schistosoma mansoni, is a complex process involving intricate cell-cell interactions in which intercellular adhesion molecules are likely to participate. To examine this possibility, sera of schistosomiasis patients in various clinical groups were assayed for the presence of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble E-selectin (sE-selectin). Comparisons were made between groups with different infection intensities (as predicted by fecal egg count) as well as between groups with severe (hepatosplenic) or milder (intestinal) pathology. All groups had elevated levels of sICAM-1 compared with controls. Also, patients in the high egg-excreting and hepatosplenic groups had significantly higher levels of serum sICAM-1 than patients in the low-egg-excreting and intestinal groups, respectively. The levels of sE-selectin were significantly elevated in the sera of all patients except those in the hepatosplenic group compared with controls. Patients in the intestinal group had significantly higher levels of sE-selectin in their sera than did hepatosplenic group patients, but serum sE-selectin levels of high- and low-egg-excreting patients were comparable. A striking finding of this study was the inverse correlation observed between sICAM-1 levels and peripheral blood mononuclear cell responses to schistosome soluble egg antigens (SEA) but not with responses to other schistosome antigens, purified protein derivative, or mitogen. Because ICAM-1 can perform a costimulatory function in antigen-presenting cell-T cell interactions, it is possible that shedding of ICAM-1 in the granuloma microenvironment interrupts proper costimulation, leading to unresponsive SEA-specific T cells. In this way, sICAM-1 could be one factor contributing to the observed modulation of cellular responses to SEA in chronic human schistosomiasis. PMID:7516309
Platelet endothelial cell adhesion molecule-1 polymorphism in patients with bronchial asthma.
Nadi, Ebrahim; Hajilooi, Mehrdad; Babakhani, Davood; Rafiei, Alireza
Asthma is considered as a chronic inflammatory airway disease and defined as increased tracheobronchial responsiveness to variety of stimuli. Edema and inflammatory cell infiltration in airway is observed in the asthmatic patients. One of the essential changes in inflammation is adhesion of leukocyte to endothelium and transmigration of leukocytes to the sites of inflammation. Unfortunately, little is known about the role of platelet endothelial cell adhesion molecule-1 (PECAM-1) polymorphism in asthma inflammatory process. The purpose of this study was to determine whether PECAM-1 polymorphisms affect the risk of asthma or not.Forty-five asthmatic patients (including 27 men and 18 women) and 45 healthy volunteers (11 men and 34 women) were studied. To determine the severity of the asthmas situation, a questionnaire was prepared asking the following information: age, sex, clinical signs and symptoms and past medical history. All subjects were genotyped for PECAM-1 polymorphism by using amplification refractory mutation system -polymerase chain reaction (ARMS-PCR). The genotype distribution of PECAM-1 80 Val/Met polymorphism in all asthmatic patients were Val/Val while non asthmatic controls were 95.6% Val/Val and 4.4% Val/Met. However, these differences were not statistically significant (p<0.05). The allele and genotype frequencies of PECAM-1 125 Val/Leu polymorphism were significantly different between asthmatic patients and controls. On the other hand, the presence of 125 Leu allele was associated with an increasing risk of asthma with an odds ratio of 2.8 (95% CI; 1.5-5.3, p=0.002). Our findings suggest that the PECAM-1 125 Val/leu polymorphism might be a genetic factor that may be associated with asthma. PMID:23264403
Role of Intercellular Adhesion Molecule-1 in Radiation-Induced Brain Injury
Wu, K.-L.; Tu Ba; Li Yuqing [Discipline of Molecular and Cell Biology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Wong, C. Shun, E-mail: firstname.lastname@example.com [Discipline of Molecular and Cell Biology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)
Purpose: To determine the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of brain injury after irradiation (IR). Methods and Materials: We assessed the expression of ICAM-1 in mouse brain after cranial IR and determined the histopathologic and behavioral changes in mice that were either wildtype (+/+) or knockout (-/-) of the ICAM-1 gene after IR. Results: There was an early dose-dependent increase in ICAM-1 mRNA and protein expression after IR. Increased ICAM-1 immunoreactivity was observed in endothelia and glia of ICAM-1+/+ mice up to 8 months after IR. ICAM-1-/- mice showed no expression. ICAM-1+/+ and ICAM-1-/- mice showed similar vascular abnormalities at 2 months after 10-17 Gy, and there was evidence for demyelination and inhibition of hippocampal neurogenesis at 8 months after 10 Gy. After 10 Gy, irradiated ICAM-1+/+ and ICAM-1-/- mice showed similar behavioral changes at 2-6 months in open field, light-dark chamber, and T-maze compared with age-matched genotype controls. Conclusion: There is early and late upregulation of ICAM-1 in the vasculature and glia of mouse brain after IR. ICAM-1, however, does not have a causative role in the histopathologic injury and behavioral dysfunction after moderate single doses of cranial IR.
Increased Osteoclastogenesis in Mice Lacking the Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1
Jeschke, Anke; Seitz, Sebastian; Schulze, Jochen; Ito, Wulf D.; Zimmermann, Wolfgang; Amling, Michael; Schinke, Thorsten; Horst, Andrea Kristina; Keller, Johannes
Alterations in bone remodeling are a major public health issue, as therapeutic options for widespread bone disorders such as osteoporosis and tumor-induced osteolysis are still limited. Therefore, a detailed understanding of the regulatory mechanism governing bone cell differentiation in health and disease are of utmost clinical importance. Here we report a novel function of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), a member of the immunoglobulin superfamily involved in inflammation and tumorigenesis, in the physiologic regulation of bone remodeling. Assessing the expression of all members of the murine Ceacam family in bone tissue and marrow, we found CEACAM1 and CEACAM10 to be differentially expressed in both bone-forming osteoblasts and bone-resorbing osteoclasts. While Ceacam10-deficient mice displayed no alteration in structural bone parameters, static histomorphometry demonstrated a reduced trabecular bone mass in mice lacking CEACAM1. Furthermore, cellular and dynamic histomorphometry revealed an increased osteoclast formation in Ceacam1-deficient mice, while osteoblast parameters and the bone formation rate remained unchanged. In line with these findings, we detected accelerated osteoclastogenesis in Ceacam1-deficient bone marrow cells, while osteoblast differentiation, as determined by mineralization and alkaline phosphatase assays, was not affected. Therefore, our results provide in vivo and in vitro evidence for a physiologic role of CEACAM1 in the regulation of osteoclastogenesis. PMID:25490771
Tetraspanins CD81 and CD82 Facilitate ?4?1-Mediated Adhesion of Human Erythroblasts to Vascular Cell Adhesion Molecule-1
Spring, Frances A.; Griffiths, Rebecca E.; Mankelow, Tosti J.; Agnew, Christopher; Parsons, Stephen F.; Chasis, Joel A.; Anstee, David J.
The proliferation and terminal differentiation of erythroid progenitors occurs in human bone marrow within erythroblastic islands, specialised structures consisting of a central macrophage surrounded by developing erythroid cells. Many cell-cell and cell-matrix adhesive interactions maintain and regulate the co-ordinated daily production of reticulocytes. Erythroid cells express only one integrin, ?4?1, throughout differentiation, and its interactions with both macrophage Vascular Cell Adhesion Molecule-1 and with extracellular matrix fibronectin are critical for erythropoiesis. We observed that proerythroblasts expressed a broad tetraspanin phenotype, and investigated whether any tetraspanin could modulate integrin function. A specific association between ?4?1 and CD81, CD82 and CD151 was demonstrated by confocal microscopy and co-immune precipitation. We observed that antibodies to CD81 and CD82 augmented adhesion of proerythroblasts to Vascular Cell Adhesion Molecule-1 but not to the fibronectin spliceoforms FnIII12-IIICS-15 and FnIII12¢15. In contrast, different anti-CD151 antibodies augmented or inhibited adhesion of proerythroblasts to Vascular Cell Adhesion Molecule-1 and the fibronectin spliceoform FnIII12-IIICS-15 but not to FnIII12¢15. These results strongly suggest that tetraspanins have a functional role in terminal erythropoiesis by modulating interactions of erythroblast ?4?1 with both macrophages and extracellular matrix. PMID:23704882
Tetraspanins CD81 and CD82 facilitate ?4?1-mediated adhesion of human erythroblasts to vascular cell adhesion molecule-1.
Spring, Frances A; Griffiths, Rebecca E; Mankelow, Tosti J; Agnew, Christopher; Parsons, Stephen F; Chasis, Joel A; Anstee, David J
The proliferation and terminal differentiation of erythroid progenitors occurs in human bone marrow within erythroblastic islands, specialised structures consisting of a central macrophage surrounded by developing erythroid cells. Many cell-cell and cell-matrix adhesive interactions maintain and regulate the co-ordinated daily production of reticulocytes. Erythroid cells express only one integrin, ?4?1, throughout differentiation, and its interactions with both macrophage Vascular Cell Adhesion Molecule-1 and with extracellular matrix fibronectin are critical for erythropoiesis. We observed that proerythroblasts expressed a broad tetraspanin phenotype, and investigated whether any tetraspanin could modulate integrin function. A specific association between ?4?1 and CD81, CD82 and CD151 was demonstrated by confocal microscopy and co-immune precipitation. We observed that antibodies to CD81 and CD82 augmented adhesion of proerythroblasts to Vascular Cell Adhesion Molecule-1 but not to the fibronectin spliceoforms FnIII12-IIICS-15 and FnIII12-15. In contrast, different anti-CD151 antibodies augmented or inhibited adhesion of proerythroblasts to Vascular Cell Adhesion Molecule-1 and the fibronectin spliceoform FnIII12-IIICS-15 but not to FnIII12-15. These results strongly suggest that tetraspanins have a functional role in terminal erythropoiesis by modulating interactions of erythroblast ?4?1 with both macrophages and extracellular matrix. PMID:23704882
Interaction of Intercellular Adhesion Molecule 1 (ICAM1) Polymorphisms and Environmental Tobacco Smoke on Childhood Asthma
Li, Yu-Fen; Lin, Che-Chen; Tai, Chien-Kuo
Asthma is a chronic disease that is particularly common in children. The association between polymorphisms of the gene encoding intercellular adhesion molecule 1 (ICAM1) and gene-environment interactions with childhood asthma has not been fully investigated. A cross-sectional study was undertaken to investigate these associations among children in Taiwan. The effects of two functional single-nucleotide polymorphisms (SNPs) of ICAM1, rs5491 (K56M) and rs5498 (K469E), and exposure to environmental tobacco smoke (ETS) were studied. Two hundred and eighteen asthmatic and 877 nonasthmatic children were recruited from elementary schools. It was found that the genetic effect of each SNP was modified by the other SNP and by exposure to ETS. The risk of asthma was higher for children carrying the rs5491 AT or TT genotypes and the rs5498 GG genotype (odds ratio = 1.68, 95% confidence interval 1.09¢2.59) than for those with the rs5491 AA and rs5498 AA or AG genotypes (the reference group). The risk for the other two combinations of genotypes did not differ significantly from that of the reference group (p of interaction = 0.0063). The two studied ICAM1 SNPs were associated with childhood asthma among children exposed to ETS, but not among those without ETS exposure (p of interaction = 0.05 and 0.01 for rs5491 and rs5498, respectively). Both ICAM1 and ETS, and interactions between these two factors are likely to be involved in the development of asthma in childhood. PMID:25003170
Intercellular Adhesion Molecule 1 Promotes HIV-1 Attachment but Not Fusion to Target Cells
Kondo, Naoyuki; Melikyan, Gregory B.
Incorporation of intercellular adhesion molecule 1 (ICAM-1) into HIV-1 particles is known to markedly enhance the virus binding and infection of cells expressing lymphocyte function-associated antigen-1 (LFA-1). At the same time, ICAM-1 has been reported to exert a less pronounced effect on HIV-1 fusion with lymphoid cells. Here we examined the role of ICAM-1/LFA-1 interactions in productive HIV-1 entry into lymphoid cells using a direct virus-cell fusion assay. ICAM-1 promoted HIV-1 attachment to cells in a temperature-dependent manner. It exerted a marginal effect on virus binding in the cold, but enhanced binding up to 4-fold at physiological temperature. ICAM-1-independent attachment in the cold was readily reversible upon subsequent incubation at elevated temperature, whereas ICAM-1-bearing particles were largely retained by cells. The better virus retention resulted in a proportional increase in HIV-1 internalization and fusion, suggesting that ICAM-1 did not specifically accelerate endocytosis or fusion steps. We also measured the rates of CD4 engagement, productive endocytosis and HIV-endosome fusion using specific fusion inhibitors. These rates were virtually independent of the presence of ICAM-1 in viral particles. Importantly, irrespective of the presence of ICAM-1, HIV-1 escaped from the low temperature block, which stopped virus endocytosis and fusion, much later than from a membrane-impermeant fusion inhibitor targeting surface-accessible particles. This result, along with the complete inhibition of HIV-1 fusion by a small molecule dynamin inhibitor, implies this virus enters lymphoid cells used in this study via endocytosis and that this pathway is not altered by the viral ICAM-1. Our data highlight the role of ICAM-1 in stabilizing the HIV-1 attachment to LFA-1 expressing cells, which leads to a proportional enhancement of the receptor-mediated uptake and fusion with endosomes. PMID:22970312
Impact of Intercellular Adhesion Molecule-1 Genetic Polymorphisms on Coronary Artery Disease Susceptibility in Taiwanese Subjects
Chou, Chi-Hung; Ueng, Kwo-Chang; Liu, Yu-Fan; Wu, Chih-Hsien; Yang, Shun-Fa; Wang, Po-Hui
The principal pathogenesis of coronary artery disease (CAD) is coronary artery atherosclerosis, a chronic inflammatory disease of the vessel walls of the coronary artery. Intercellular adhesion molecule-1 (ICAM-1) displays an important role in the development of the inflammation reaction and atherosclerosis. Few studies report the association of ICAM-1 genetic polymorphisms with CAD in Taiwanese subjects. Therefore, we conducted a study to associate the single nucleotide polymorphisms (SNPs) of ICAM-1, rs5491, rs5498, rs281432 and rs3093030 with CAD. Five hundred and twenty-five male and female subjects, who received elective coronary angiography in Taiwan Chung Shan Medical University Hospital, were recruited to determine four ICAM-1 SNPs by real time-polymerase chain reaction and genotyping. The relationships among ICAM-1 SNPs, haplotypes, demographic and characteristics and CAD were analyzed. This study showed that rs281432 (C8823G) was the only ICAM-1 SNP which affect the development of CAD. Multivariate analysis revealed that ICAM-1 SNP rs281432 CC/CG [p=0.016; odds ratio (OR): 2.56, 95% confidence interval (CI): 1.19-5.56], male gender (p=0.018; OR: 1.66, 95% CI: 1.09-2.51), aspirin use in the past 7 days (p=0.001; OR: 2.05, 95% CI: 1.33-3.14), hypertension (p<0.001; OR: 2.15, 95% CI: 1.42-3.25), serum cardiac troponin I elevation (p<0.001; OR: 2.14, 95% CI: 1.47-3.24) and severe angina in recent 24 hours (p=0.001; OR: 1.97, 95% CI: 1.31- 2.95) increase the risk of CAD. In conclusion, ICAM-1 SNP rs281432 is an independent factor to predict the development of CAD. ICAM-1 SNP rs281432 homozygotic mutant GG can reduce the susceptibility to the CAD in Taiwanese subjects. PMID:26078712
Intracellular Adhesion Molecule 1 Plays a Key Role in Acquired Immunity to Salmonellosis
Clare, Simon; Goldin, Robert; Hale, Christine; Aspinall, Richard; Simmons, Cameron; Mastroeni, Pietro; Dougan, Gordon
This study investigated the role of intracellular adhesion molecule 1 (ICAM-1) during Salmonella enterica serovar Typhimurium infection of mice. We show that ICAM-1 is expressed in and around granulomas on day 4 of infection in wild-type mice. However, when naive ICAM-1?/? mice were challenged with a sublethal dose of serovar Typhimurium, there were no detectable differences in systemic bacterial burden over the first 9 days of infection compared to wild-type control mice. When mice were immunized with the S. enterica serovar Typhimurium vaccine strain SL2361 and then challenged with the virulent S. enterica serovar Typhimurium strain C5, 100% of the ICAM-1?/? mice succumbed to infection, compared to 30% of wild-type mice. T-cell responses, as measured by activation via interleukin-2 production, as well as antibody responses were comparable in the ICAM-1?/? and wild-type mice. Following challenge, counts in organs were significantly higher in the ICAM-1?/? mice, and histological examination of organs showed pathological differences. Strain SL3261-immunized wild-type mice had cellular infiltrate and normal granuloma formation in the liver and spleen on days 5 and 10 after challenge with strain C5. ICAM-1?/? mice had a similar infiltrate on day 5, whereas on day 10 the infiltrate was more widespread and there were fewer macrophages associated with the granulomas. High circulating levels of tumor necrosis factor alpha and gamma interferon, as well as a high burden of strain C5 in the blood, accompanied the differences in histopathology. In this study we show that ICAM-1 plays a critical role during rechallenge of immunized mice with virulent S. enterica serovar Typhimurium. PMID:14500509
Intracellular adhesion molecule 1 plays a key role in acquired immunity to salmonellosis.
Clare, Simon; Goldin, Robert; Hale, Christine; Aspinall, Richard; Simmons, Cameron; Mastroeni, Pietro; Dougan, Gordon
This study investigated the role of intracellular adhesion molecule 1 (ICAM-1) during Salmonella enterica serovar Typhimurium infection of mice. We show that ICAM-1 is expressed in and around granulomas on day 4 of infection in wild-type mice. However, when naive ICAM-1(-/-) mice were challenged with a sublethal dose of serovar Typhimurium, there were no detectable differences in systemic bacterial burden over the first 9 days of infection compared to wild-type control mice. When mice were immunized with the S. enterica serovar Typhimurium vaccine strain SL2361 and then challenged with the virulent S. enterica serovar Typhimurium strain C5, 100% of the ICAM-1(-/-) mice succumbed to infection, compared to 30% of wild-type mice. T-cell responses, as measured by activation via interleukin-2 production, as well as antibody responses were comparable in the ICAM-1(-/-) and wild-type mice. Following challenge, counts in organs were significantly higher in the ICAM-1(-/-) mice, and histological examination of organs showed pathological differences. Strain SL3261-immunized wild-type mice had cellular infiltrate and normal granuloma formation in the liver and spleen on days 5 and 10 after challenge with strain C5. ICAM-1(-/-) mice had a similar infiltrate on day 5, whereas on day 10 the infiltrate was more widespread and there were fewer macrophages associated with the granulomas. High circulating levels of tumor necrosis factor alpha and gamma interferon, as well as a high burden of strain C5 in the blood, accompanied the differences in histopathology. In this study we show that ICAM-1 plays a critical role during rechallenge of immunized mice with virulent S. enterica serovar Typhimurium. PMID:14500509
Soluble Form of Vascular Cell Adhesion Molecule 1 Induces Migration and Proliferation of Vascular Smooth Muscle Cells
Hwan Myung Lee; Hyo Jin Kim; Kyung-Jong Won; Wahn Soo Choi; Seung Hwa Park; Hyuk Song; Pyo-Jam Park; Tae-Kyu Park; Chang-Kwon Lee; Bokyung Kim
Background: Serum levels of soluble vascular cell adhesion molecule 1 (sVCAM-1) shed from its membrane-bound form are elevated in hypertension. This study clarified the effects of sVCAM-1 on vascular responses in rat aortic smooth muscle cells (RASMCs). Methods: Boyden chamber, 5-bromo-2?-deoxyuridine incorporation and ex vivo aortic ring assays for migration and proliferation, and Western blot for the kinase activity were
Carcinoembryonic Antigen-Related Cellular Adhesion Molecule 1 Isoforms Alternatively Inhibit and Costimulate Human T Cell Function1
Daohong Chen; Hideki Iijima; Takashi Nagaishi; Atsushi Nakajima; Sara Russell; Raktima Raychowdhury; Victor Morales; Christopher E. Rudd; Nalan Utku; Richard S. Blumberg
Carcinoembryonic Ag-related cellular adhesion molecule 1 (CEACAM1) represents a group of transmembrane protein isoforms that consist of variable numbers of extracellular Ig-like domains together with either a long cytoplasmic (cyt) tail containing two immunoreceptor tyrosine-based inhibitory motifs or a unique short cyt tail. Although CEACAM1 has been reported to be ex- pressed on the surface of T lymphocytes upon activation,
Monocyte adhesion to endothelium in simian immunodeficiency virus-induced AIDS encephalitis is mediated by vascular cell adhesion molecule-1/alpha 4 beta 1 integrin interactions.
Sasseville, V. G.; Newman, W.; Brodie, S. J.; Hesterberg, P.; Pauley, D.; Ringler, D. J.
Because the mechanisms associated with recruitment of monocytes to brain in AIDS encephalitis are unknown, we used tissues from rhesus monkeys infected with simian immunodeficiency virus (SIV) to examine the relative contributions of various adhesion pathways in mediating monocyte adhesion to endothelium from encephalitic brain. Using a modified Stamper and Woodruff tissue adhesion assay, we found that the human monocytic cell lines, THP-1 and U937, and the B cell line, Ramos, preferentially bound to brain vessels from monkeys with AIDS encephalitis. Using a combined tissue adhesion/immunohistochemistry approach, these cells only bound to vessels expressing vascular cell adhesion molecule-1 (VCAM-1). Furthermore, pretreatment of tissues with antibodies to VCAM-1 or cell lines with antibodies to VLA-4 (CD49d) inhibited adhesion by more than 70%. Intercellular adhesion molecule-1 (ICAM-1)/beta 2 integrin interactions were not significant in mediating cell adhesion to the vasculature in encephalitic simian brain using a cell line (JY) capable of binding rhesus monkey ICAM-1. In addition, selectin-mediated interactions did not significantly contribute to cell binding to encephalitic brain as there was no immunohistochemical expression of E-selectin and P-selectin in either normal or encephalitic brain, nor was there a demonstrable adhesive effect from L-selectin using L-selectin-transfected 300.19 cells on simian encephalitic brain. These results demonstrate that using the tissue adhesion assay, THP-1, U937, and Ramos cells bind to vessels in brain from animals with AIDS encephalitis using VCAM-1/alpha 4 beta 1 integrin interactions and suggest that VCAM-1 and VLA-4 may be integral for monocyte recruitment to the central nervous system during the development of AIDS encephalitis. Images Figure 1 PMID:7507300
Lymphocyte Function-associated Antigen-1 (LFA-1)Interaction with Intercellular Adhesion Molecule-1 (ICAM-1) is One of At Least Three
Springer, Timothy A.
Lymphocyte Function-associated Antigen-1 (LFA-1)Interaction with Intercellular Adhesion Molecule-1 by monoclonal antibodies to lymphocyte func- tion associated antigen-1 (LFA-1) or ICAM-I. Adhesion to artificial and stimulated endothelial cells. Adhesion of JY B lymphoblastoid cells, normal and genetically LFA-1 deficient
Soluble platelet-endothelial cell adhesion molecule-1, a biomarker of ventilator-induced lung injury
Introduction Endothelial cell injury is an important component of acute lung injury. Platelet-endothelial cell adhesion molecule-1 (PECAM1) is a transmembrane protein that connects endothelial cells to one another and can be detected as a soluble, truncated protein (sPECAM1) in serum. We hypothesized that injurious mechanical ventilation (MV) leads to shedding of PECAM1 from lung endothelial cells resulting in increasing sPECAM1 levels in the systemic circulation. Methods We studied 36 Sprague¢Dawley rats in two prospective, randomized, controlled studies (healthy and septic) using established animal models of ventilator-induced lung injury. Animals (n?=?6 in each group) were randomized to spontaneous breathing or two MV strategies: low tidal volume (VT) (6Āml/kg) and high-VT (20Āml/kg) on 2 cmH2O of positive end-expiratory pressure (PEEP). In low-VT septic animals, 10 cmH2O of PEEP was applied. We performed pulmonary histological and physiological evaluation and measured lung PECAM1 protein content and serum sPECAM1 levels after four hours ventilation period. Results High-VT MV caused severe lung injury in healthy and septic animals, and decreased lung PECAM1 protein content (P?0.001). Animals on high-VT had a four- to six-fold increase of mean sPECAM1 serum levels than the unventilated counterpart (35.4?▒?10.4 versus 5.6?▒?1.7Āng/ml in healthy rats; 156.8?▒?47.6 versus 35.6?▒?12.6Āng/ml in septic rats) (P?0.0001). Low-VT MV prevented these changes. Levels of sPECAM1 in healthy animals on high-VT MV paralleled the sPECAM1 levels of non-ventilated septic animals. Conclusions Our findings suggest that circulating sPECAM1 may represent a promising biomarker for the detection and monitoring of ventilator-induced lung injury. PMID:24588994
Arsenite enhances tumor necrosis factor-{alpha}-induced expression of vascular cell adhesion molecule-1
Tsou, T.-C. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China)]. E-mail: firstname.lastname@example.com; Yeh, Szu Ching [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China); Tsai, E.-M. [Department of Obstetrics and Gynecology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Obstetrics and Gynecology, Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung, Taiwan (China); Tsai, F.-Y. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China); Chao, H.-R. [Department of Environmental and Safety Health Engineering, Chung Hwa College of Medical Technology, Tainan, Taiwan (China); Chang, Louis W. [Division of Environmental Health and Occupational Medicine, National Health Research Institutes, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan (China)
Epidemiological studies demonstrated a high association of vascular diseases with arsenite exposure. We hypothesize that arsenite potentiates the effect of proinflammatory cytokines on vascular endothelial cells, and hence contributes to atherosclerosis. In this study, we investigated the effect of arsenite and its induction of glutathione (GSH) on vascular cell adhesion molecule-1 (VCAM-1) protein expression in human umbilical vein endothelial cells (HUVECs) in response to tumor necrosis factor-{alpha} (TNF-{alpha}), a typical proinflammatory cytokine. Our study demonstrated that arsenite pretreatment potentiated the TNF-{alpha}-induced VCAM-1 expression with up-regulations of both activator protein-1 (AP-1) and nuclear factor-{kappa}B (NF-{kappa}B). To elucidate the role of GSH in regulation of AP-1, NF-{kappa}B, and VCAM-1 expression, we employed L-buthionine (S,R)-sulfoximine (BSO), a specific {gamma}-glutamylcysteine synthetase ({gamma}-GCS) inhibitor, to block intracellular GSH synthesis. Our investigation revealed that, by depleting GSH, arsenite attenuated the TNF-{alpha}-induced VCAM-1 expression as well as a potentiation of AP-1 and an attenuation of NF-{kappa}B activations by TNF-{alpha}. Moreover, we found that depletion of GSH would also attenuate the TNF-{alpha}-induced VCAM-1 expression with a down-regulation of the TNF-{alpha}-induced NF-{kappa}B activation and without significant effect on AP-1. On the other hand, the TNF-{alpha}-induced VCAM-1 expression could be completely abolished by inhibition of AP-1 or NF-{kappa}B activity, suggesting that activation of both AP-1 and NF-{kappa}B was necessary for VCAM-1 expression. In summary, we demonstrate that arsenite enhances the TNF-{alpha}-induced VCAM-1 expression in HUVECs via regulation of AP-1 and NF-{kappa}B activities in a GSH-sensitive manner. Our present study suggested a potential mechanism for arsenite in the induction of vascular inflammation and vascular diseases via modulating the actions of proinflammatory cytokines.
High level of intercellular adhesion molecule-1 affects prognosis of patients with hepatocellular carcinoma
Zhu, Peng-Peng; Yuan, Sheng-Guang; Liao, Yan; Qin, Li-Ling; Liao, Wei-Jia
AIM: To determine the cut-off value of intercellular adhesion molecule-1 (ICAM-1) and assess the correlation of ICAM-1 with clinicopathological features and the prognosis of hepatocellular carcinoma (HCC) patients who underwent surgical resection. METHODS: We prospectively collected clinicopathological data from 236 HCC patients who had undergone successful hepatectomy. Receiver operating characteristic curve analysis was performed to determine the optimal cut-off value of ICAM-1. Enzyme-linked immunosorbent assay was used to measure the concentration of ICAM-1 in 236 serum samples isolated from HCC patients and the stratified analysis was used to compare the serum level of ICAM-1 in different HCC subgroups. Immunohistochemistry was performed to test the expression level of the ICAM-1 protein in 76 cases of HCC tissues and their adjacent normal liver tissues (ANLT). The survival probability of HCC patients was estimated using Kaplan-Meier plots and differences between the groups were obtained using the log-rank test. Furthermore, independent indicators of the prognosis were acquired using a stepwise Cox proportional hazard model to analyze a series of predictors that were associated with disease-free survival (DFS) and overall survival (OS) in HCC patients. RESULTS: Our findings suggested that ICAM-1 promotes HCC metastasis and high serum ICAM-1 is significantly associated with alpha-fetoprotein (AFP) (P = 0.022), clinical tumor-node-metastasis stage (P < 0.001), portal vein tumor thrombus (P = 0.005), distant metastasis (P = 0.016) and recurrence (P = 0.034). We further detected the ICAM-1 protein in HCC specimens and found that 56 of 76 (73.7%) HCC tissues had ICAM-1 positive staining while only 23 of 76 (30.3%) ANLT were positively stained (P < 0.0001). Survival analysis indicated that HCC patients with increased ICAM-1 concentrations had significantly shorter DFS and OS after resection. A multivariate analysis showed that ICAM-1 > 684 ng/mL was an independent factor for DFS (HR = 1.643; 95%CI: 1.125-2.401; P = 0.010) and OS (HR = 1.692; 95%CI: 1.152-2.486; P = 0.007). CONCLUSION: ICAM-1 may be a promising serological biomarker for HCC diagnosis and an independent predictor of DFS and OS after surgical resection and may provide a useful reference for the prediction of intra- and extrahepatic metastasis. PMID:26109813
Vascular Cell Adhesion Molecule-1 Expression and Signaling During Disease: Regulation by Reactive Oxygen Species and Antioxidants
Marchese, Michelle E.; Abdala-Valencia, Hiam
Abstract The endothelium is immunoregulatory in that inhibiting the function of vascular adhesion molecules blocks leukocyte recruitment and thus tissue inflammation. The function of endothelial cells during leukocyte recruitment is regulated by reactive oxygen species (ROS) and antioxidants. In inflammatory sites and lymph nodes, the endothelium is stimulated to express adhesion molecules that mediate leukocyte binding. Upon leukocyte binding, these adhesion molecules activate endothelial cell signal transduction that then alters endothelial cell shape for the opening of passageways through which leukocytes can migrate. If the stimulation of this opening is blocked, inflammation is blocked. In this review, we focus on the endothelial cell adhesion molecule, vascular cell adhesion molecule-1 (VCAM-1). Expression of VCAM-1 is induced on endothelial cells during inflammatory diseases by several mediators, including ROS. Then, VCAM-1 on the endothelium functions as both a scaffold for leukocyte migration and a trigger of endothelial signaling through NADPH oxidase-generated ROS. These ROS induce signals for the opening of intercellular passageways through which leukocytes migrate. In several inflammatory diseases, inflammation is blocked by inhibition of leukocyte binding to VCAM-1 or by inhibition of VCAM-1 signal transduction. VCAM-1 signal transduction and VCAM-1-dependent inflammation are blocked by antioxidants. Thus, VCAM-1 signaling is a target for intervention by pharmacological agents and by antioxidants during inflammatory diseases. This review discusses ROS and antioxidant functions during activation of VCAM-1 expression and VCAM-1 signaling in inflammatory diseases. Antioxid. Redox Signal. 15, 1607¢1638. PMID:21050132
Intercellular adhesion molecule 1: recent findings and new concepts involved in mammalian spermatogenesis
Mruk, Dolores D.; Xiao, Xiang; Lydka, Marta; Li, Michelle W.M.; Bilinska, Barbara; Cheng, C. Yan
Spermatogenesis, the process of spermatozoa production, is regulated by several endocrine factors, including testosterone, follicle stimulating hormone, luteinizing hormone and estradiol 17?. For spermatogenesis to reach completion, developing germ cells must traverse the seminiferous epithelium while remaining transiently attached to Sertoli cells. If germ cell adhesion were to be compromised for a period of time longer than usual, germ cells would slough the seminiferous epithelium and infertility would result. Presently, Sertoli-germ cell adhesion is known to be mediated largely by classical and desmosomal cadherins. More recent studies, however, have begun to expand long-standing concepts and to examine the roles of other proteins such as intercellular adhesion molecules. In this review, we focus on the biology of intercellular adhesion molecules in the mammalian testis, hoping that this information is useful in the design of future studies. PMID:24445189
Increased blood plasminogen activator inhibitor-1 and intercellular adhesion molecule-1 as possible risk factors of atherosclerosis in Werner syndrome.
Murano, S; Nakazawa, A; Saito, I; Masuda, M; Morisaki, N; Akikusa, B; Tsuboyama, T; Saito, Y
Werner syndrome is a rare premature aging syndrome accompanied by severe atherosclerosis. The etiology of atherosclerosis is suspected to be due to its complications, namely diabetes mellitus, hyperinsulinemia and hyperlipidemia. But from an autopsy case we found that some other risk factors may be involved in the mechanism of atherosclerosis in this syndrome. Previously we revealed that the plasminogen activator inhibitor-1 (PAI-1) gene was being overexpressed in skin fibroblasts from a patient with this syndrome. PAI-1 is a potent inhibitor of tissue plasminogen activator and a possible risk factor of atherosclerosis. This led us to assess the plasma concentration of PAI-1. Our working hypothesis was that the PAI-1 gene was upregulated or not fully suppressed in cells responsible for the production of PAI-1 in plasma as well as in fibroblasts. The results show a high concentration of plasma PAI-1. One of the well-known physiological substances that induce the PAI-1 gene is tumor necrosis factor-alpha, which also induces other possible risk factors of atherosclerosis, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1. We found the serum concentrations of ICAM-1 to be elevated in patients with this syndrome. We conclude that high concentrations of PAI-1 and ICAM-1 in blood may be one of the potent causes of severe atherosclerosis in Werner syndrome. PMID:9187938
Benzo[a]pyrene induces intercellular adhesion molecule-1 through a caveolae and aryl hydrocarbon receptor mediated pathway
Oesterling, Elizabeth [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536-0200 (United States); Toborek, Michal [Department of Neurosurgery, College of Medicine, University of Kentucky, Lexington, KY 40536-0200 (United States); Hennig, Bernhard [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536-0200 (United States); Molecular and Cell Nutrition Laboratory, College of Agriculture, University of Kentucky, Lexington, KY 40536-0200 (United States)], E-mail: email@example.com
Toxicologic and epidemiologic studies have linked benzo[a]pyrene (B[a]P) exposure with cardiovascular diseases such as atherosclerosis. The mechanisms of action leading to these diseases have not been fully understood. One key step in the development of atherosclerosis is vascular endothelial dysfunction, which is characterized by increased adhesiveness. To determine if B[a]P could lead to increased endothelial adhesiveness, the effects of B[a]P on human endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression was investigated. B[a]P was able to increase ICAM-1 protein only after pretreatment with the aryl hydrocarbon receptor (AhR) agonist {beta}-naphthoflavone ({beta}-NF). Knockdown of AhR by siRNA or treatment with AhR antagonist {alpha}-naphthoflavone ({alpha}-NF) eliminated the induction of ICAM-1 from B[a]P, confirming the necessity of AhR in this process. Likewise, B[a]P only increased monocyte adhesion to the vascular endothelium when cells were pretreated with {beta}-NF. Experiments were done to define a signaling mechanism. B[a]P increased phosphorylation of MEK and p38-MAPK, and inhibitors to these proteins blunted the ICAM-1 induction. B[a]P was also able to increase AP-1 DNA binding and phosphorylation of cJun. Phosphorylation of cJun was disrupted by MEK and p38-MAPK inhibitors linking the signaling cascade. Finally, the importance of membrane microdomains, caveolae, was demonstrated by knockdown of the structural protein caveolin-1. Disruption of caveolae eliminated the B[a]P-induced ICAM-1 expression. These data suggest a possible pro-inflammatory mechanism of action of B[a]P involving caveolae, leading to increased vascular endothelial adhesiveness, and this inflammation may be a critical step in the development of B[a]P-induced atherosclerosis.
Leukocytosis and Resistance to Septic Shock in Intercellular Adhesion Molecule 1-deficient Mice
Springer, Timothy A.
immunoglobulin superfamily mem- bers that bind to the integrins lymphocytefunction associated 1 (LFA-1) and Mac-1 is composed of three members, LFA-1 (CDlla/CD18), Mac-1 (CDllb/CD18), and p150,95 (CDllc/CD18) (1, 2). LFA-1. LFA-1 binds to three Ig superfamily members, intercellular adhesion molecule (ICAM)1 1, 2, and 3 (3
Platelet endothelial cell adhesion molecule-1 signaling inhibits the activation of human platelets
Milenko Cicmil; Joanne M. Thomas; Mireille Leduc; Cassian Bon; Jonathan M. Gibbins
Platelet endothelial cell adhesion mole- cule-1 (PECAM-1\\/CD31) is a 130-kd trans- membrane glycoprotein and a member of the growing family of receptors with im- munoreceptor tyrosine-based inhibitory motifs (ITIMs). PECAM-1 is expressed on platelets, certain T cells, monocytes, neu- trophils, and vascular endothelial cells and is involved in a range of cellular processes, though the role of PECAM-1 in platelets
Hypermethylation of the tumor-suppressor cell adhesion molecule 1 in human papillomavirus-transformed cervical carcinoma cells
Epigenetic modification at CpG islands located on the promoter regions of tumor-suppressor genes has been associated with tumor development in many human cancers. Our study showed that the cell adhesion molecule 1 (CADM1) is downregulated in human papillomavirus (HPV)-infected cervical cancer cell lines via its hypermethylation and demethylation using 5-aza-2?-deoxycyticine (5-aza-dC) restored the expression of CADM1 protein. Overexpression of CADM1 inhibited cell proliferation. p53 was involved in the regulation of CADM1. Our results demonstrate that epigenetic alteration of CADM1 was more frequent in HPV-positive cervical cancers and that restoration of CADM1 expression may be a potential strategy for cervical cancer therapy. PMID:25845528
Identification of the binding site in intercellular adhesion molecule 1 for its receptor, leukocyte function-associated antigen 1.
Fisher, K L; Lu, J; Riddle, L; Kim, K J; Presta, L G; Bodary, S C
Intercellular adhesion molecule 1 (ICAM-1, CD54) is a member of the Ig superfamily and is a counterreceptor for the beta 2 integrins: lymphocyte function-associated antigen 1 (LFA-1, CD11a/CD18), complement receptor 1 (MAC-1, CD11b/CD18), and p150,95 (CD11c/CD18). Binding of ICAM-1 to these receptors mediates leukocyte-adhesive functions in immune and inflammatory responses. In this report, we describe a cell-free assay using purified recombinant extracellular domains of LFA-1 and a dimeric immunoadhesin of ICAM-1. The binding of recombinant secreted LFA-1 to ICAM-1 is divalent cation dependent (Mg2+ and Mn2+ promote binding) and sensitive to inhibition by antibodies that block LFA-1-mediated cell adhesion, indicating that its conformation mimics that of LFA-1 on activated lymphocytes. We describe six novel anti-ICAM-1 monoclonal antibodies, two of which are function blocking. Thirty-five point mutants of the ICAM-1 immunoadhesin were generated and residues important for binding of monoclonal antibodies and purified LFA-1 were identified. Nineteen of these mutants bind recombinant LFA-1 equivalently to wild type. Sixteen mutants show a 66-2500-fold decrease in LFA-1 binding yet, with few exceptions, retain binding to the monoclonal antibodies. These mutants, along with modeling studies, define the LFA-1 binding site on ICAM-1 as residues E34, K39, M64, Y66, N68, and Q73, that are predicted to lie on the CDFG beta-sheet of the Ig fold. The mutant G32A also abrogates binding to LFA-1 while retaining binding to all of the antibodies, possibly indicating a direct interaction of this residue with LFA-1. These data have allowed the generation of a highly refined model of the LFA-1 binding site of ICAM-1. Images PMID:9188101
Interleukin8 and Intercellular Adhesion Molecule 1 Regulation in Oral Epithelial Cells by Selected Periodontal Bacteria: Multiple Effects of Porphyromonas gingivalis via Antagonistic Mechanisms
Interaction of bacteria with mucosal surfaces can modulate the production of proinflammatory cytokines and adhesion molecules produced by epithelial cells. Previously, we showed that expression of interleukin-8 (IL-8) and intercellular adhesion molecule 1 (ICAM-1) by gingival epithelial cells increases following inter- action with several putative periodontal pathogens. In contrast, expression of IL-8 and ICAM-1 is reduced after Porphyromonas gingivalis ATCC
Vascular adhesion molecule-1 and markers of platelet function before and after a treatment with iloprost or a supervised physical exercise program in patients with peripheral arterial disease
Enrico Arosio; Pietro Minuz; Manlio Prior; Valeria Zuliani; Stefania Gaino; Sergio De Marchi; Luigi Fontana; Giuseppe Andrioli; Clara Lechi; Alessandro Lechi
Platelet function and levels of vascular adhesion molecule-1 (VCAM-1) were investigated in 24 patients with peripheral arterial disease at Fontaine stage II undergoing a 2 weeks treatment with iloprost (0.5¢2 ng\\/kg\\/h i.v. infused, 6 h\\/day) or a 2 weeks supervised physical training, randomly assigned. Patients were studied before (T0) and after (T14) treatments and 10 days later (T24). The adhesion
5,7-Dihydroxy-3,4,6-trimethoxyflavone inhibits intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 via the Akt and nuclear factor-?B-dependent pathway, leading to suppression of adhesion of monocytes and eosinophils to bronchial epithelial cells
Jung, Jireh; Ko, Su H; Yoo, Do Y; Lee, Jin Y; Kim, Yeong-Jeon; Choi, Seul M; Kang, Kyung K; Yoon, Ho J; Kim, Hyeyoung; Youn, Jeehee; Kim, Jung M
5,7-Dihydroxy-3?,4?,6?-trimethoxyflavone (eupatilin), the active pharmacological ingredient from Artemisia asiatica Nakai (Asteraceae), is reported to have a variety of anti-inflammatory properties in intestinal epithelial cells. However, little information is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelial inflammation. This study investigates the role of eupatilin in the adhesion of inflammatory cells such as monocytes and eosinophils to bronchial epithelial cells. Stimulation of a human bronchial epithelial cell line (BEAS-2B) with tumour necrosis factor-? (TNF-?) increased the expression of surface adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in which eupatilin significantly inhibited the expression of those adhesion molecules in a dose-dependent manner. Eupatilin suppressed the TNF-?-induced activation of I?B? and nuclear factor-?B (NF-?B) signals in BEAS-2B cells. The I?B kinase (IKK) activation was also significantly reduced in eupatilin-pre-treated BEAS-2B and primary normal human bronchial epithelial (NHBE) cells. However, eupatilin did not influence AP-1 activity in TNF-?-stimulated cells. Suppression of NF-?B signalling induced by eupatilin resulted in the inhibition of the expression of adhesion molecules and the adhesion of monocytes and eosinophils to BEAS-2B cells. Furthermore, eupatilin suppressed the phosphorylation of Akt in TNF-?-stimulated BEAS-2B and NHBE cells, leading to down-regulation of NF-?B activation and adhesion molecule expression and finally to suppression of the inflammatory cell adhesion to epithelial cells. These results suggest that eupatilin can inhibit the adhesion of inflammatory cells to bronchial epithelial cells via a signalling pathway, including activation of Akt and NF-?B, as well as expression of adhesion molecules. PMID:22862554
The CO donor CORM-2 inhibits LPS-induced vascular cell adhesion molecule-1 expression and leukocyte adhesion in human rheumatoid synovial fibroblasts
Chi, Pei-Ling; Chuang, Yu-Chen; Chen, Yu-Wen; Lin, Chih-Chung; Hsiao, Li-Der; Yang, Chuen-Mao
BACKGROUND AND PURPOSE Infection with Gram-negative bacteria has been recognized as an initiator of rheumatoid arthritis, which is characterized by chronic inflammation and infiltration of immune cells. Carbon monoxide (CO) exhibits anti-inflammatory properties. Here we have investigated the detailed mechanisms of vascular cell adhesion molecule-1 (VCAM-1) expression induced by LPS and if CO inhibited LPS-induced leukocyte adhesion to synovial fibroblasts by suppressing VCAM-1 expression. EXPERIMENTAL APPROACH Human rheumatoid arthritis synovial fibroblasts (RASFs) were incubated with LPS and/or the CO-releasing compound CORM-2. Effects of LPS on VCAM-1 levels were determined by analysing mRNA expression, promoter activity, protein expression, and immunohistochemical staining. The molecular mechanisms were investigated by determining the expression, activation, and binding activity of transcriptional factors using target signal antagonists. KEY RESULTS CORM-2 significantly inhibited inflammatory responses in LPS-treated RASFs by down-regulating the expression of adhesion molecule VCAM-1 and leukocyte infiltration. The down-regulation of LPS-induced VCAM-1 expression involved inhibition of the expression of phosphorylated-NF-?B p65 and AP-1 (p-c-Jun, c-Jun and c-Fos mRNA levels). These results were confirmed by chromatin immunoprecipitation assay to detect NF-?B and AP-1 DNA binding activity. CONCLUSIONS AND IMPLICATIONS LPS-mediated formation of the TLR4/MyD88/TRAF6/c-Src complex regulated NF-?B and MAPKs/AP-1 activation leading to VCAM-1 expression and leukocyte adhesion. CORM-2, which liberates CO to elicit direct biological activities, attenuated LPS-induced VCAM-1 expression by interfering with NF-?B and AP-1 activation, and significantly reduced LPS-induced immune cell infiltration of the synovium. PMID:24628691
Ginsenoside Rb1 inhibits tumor necrosis factor-alpha-induced vascular cell adhesion molecule-1 expression in human endothelial cells.
Chai, Hui; Wang, Qiuyan; Huang, Lifeng; Xie, Tian; Fu, Yan
We investigated whether ginsenoside Rb1 (Rb1) could block tumor necrosis factor-alpha (TNF-alpha)-induced over-expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) and human lung microvascular endothelial cells (HMVECs-L). Cells were treated with various concentrations of TNF-alpha with or without Rb1 pre-treatment for 16 h. The mRNA and protein levels of VCAM-1 were determined with real-time polymerase chain reaction (PCR) and flow cytometry, respectively. Human monocytic THP-1 cells labeled with fluorescent dye (Calcein-AM) was used for the adhesion assay on HUVEC monolayers. Dihydroethidium (DHE) was used to demonstrate in situ levels of superoxide production. JC-1 dye was used to measure changes in mitochondrial membrane potential. Activation of mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-kappaB) was determined by Bio-Plex immunoassay. TNF-alpha treatment significantly increased the mRNA and protein levels of VCAM-1 in HUVECs in a dose dependent manner. Rb1 pre-treatment effectively blocked the TNF-alpha-induced expression of VCAM-1 mRNA or protein by 80% and 43%, respectively (p<0.01). THP-1 adhesion was also blocked. Furthermore, Rb1 reduced the TNF-alpha-induced increase of superoxide anion production by 41% and inhibited the TNF-alpha-induced decrease of mitochondrial membrane potential by 44% in HUVECs. Rb1 also effectively blocked TNF-alpha-induced activation of p38, c-Jun N-terminal protein kinase, extracellular signal-regulated kinase 1/2 and IkappaBalpha. In conclusion, Rb1 effectively blocked the TNF-alpha-induced over-expression of VCAM-1, increased THP-1 adhesion and over-production of superoxide anion. Furthermore, Rb1 inhibited TNF-alpha-induced MAPKs and NF-kappaB activation. These data suggested that Rb1 might have potential therapeutic effects in controlling inflammation in vascular diseases. PMID:18981572
INFLAMMATORY CYTOKINES INDUCE INTERCELLULAR ADHESION MOLECULE1 (ICAM¢1) mRNA SYNTHESIS AND PROTEIN SECRETION BY HUMAN RETINAL PIGMENT EPITHELIAL CELL CULTURES
Chandrasekharam N. Nagineni; R. Krishnan Kutty; Barbara Detrick; John J. Hooks
Retinal inflammatory diseases in man are associated with an upregulation in the expression of intercellular adhesion molecule-1 (ICAM¢1) in cells within the retina and with an increase in soluble ICAM¢1 within the vitreous. These studies suggest that this protein may contribute to immunopathological processes within the eye. The effects of inflammatory mediators on the regulation of the expression and secretion
Inhibitory Effect of Dimethyl Sulfoxide on Nuclear Factor-?B Activation and Intercellular Adhesion Molecule 1 Gene Expression in Septic Rats
Cheow K. Chang; Sheila Llanes; William Schumer
Antioxidants are potent radical scavengers that protect against endotoxemia and septic shock in animal models. Using a rat model of peritonitis sepsis induced by cecal incision we studied the effect of the free radical scavenger dimethyl sulfoxide (DMSO) on hepatic nuclear factor ?B (NF-?B) activation, hepatic intercellular adhesion molecule 1 (ICAM-1) gene expression, serum tumor necrosis factor ? (TNF) formation,
Expression of a Soluble Isoform of Cell Adhesion Molecule 1 in the Brain and Its Involvement in Directional Neurite Outgrowth
Hagiyama, Man; Ichiyanagi, Naoki; Kimura, Keiko B.; Murakami, Yoshinori; Ito, Akihiko
Cell adhesion molecule 1 (CADM1), an immunoglobulin superfamily member, is expressed on superior cervical ganglion neurites and mediates cell¢cell adhesion by trans-homophilic binding. In addition to the membrane-bound form, we have previously shown that a soluble form (sCADM1) generated by alternative splicing possesses a stop codon immediately downstream of the immunoglobulin-like domain. Here, we demonstrate the presence of sCADM1 in vivo and its possible role in neurite extension. sCADM1 appears to be a stromal protein because extracellular-restricted, but not intracellular-restricted, anti-CADM1 antibody stained stromal protein-rich extract from mouse brains. Murine plasmacytoma cells, P3U1, were modified to secrete sCADM1 fused with either immunoglobulin (Ig)G Fc portion (sCADM1-Fc) or its deletion form that lacks the immunoglobulin-like domain (?sCADM1-Fc). When P3U1 derivatives expressing sCADM1-Fc or ?sCADM1-Fc were implanted into collagen gels, Fc-fused proteins were present more abundantly around the cells. Superior cervical ganglion neurons, parental P3U1, and either derivative were implanted into collagen gels separately, and co-cultured for 4 days. Bodian staining of the gel sections revealed that most superior cervical ganglion neurites turned toward the source of sCADM1-Fc, but not ?sCADM1-Fc. Furthermore, immunofluorescence signals for sCADM1-Fc and membrane-bound CADM1 were co-localized on the neurite surface. These results show that sCADM1 appears to be involved in directional neurite extension by serving as an anchor to which membrane-bound CADM1 on the neurites can bind. PMID:19435791
Human mucosal addressin cell adhesion molecule-1 is preferentially expressed in intestinal tract and associated lymphoid tissue.
Briskin, M.; Winsor-Hines, D.; Shyjan, A.; Cochran, N.; Bloom, S.; Wilson, J.; McEvoy, L. M.; Butcher, E. C.; Kassam, N.; Mackay, C. R.; Newman, W.; Ringler, D. J.
Lymphocyte homing to normal tissues and recruitment to inflammatory tissue sites are controlled, in part, by the selective expression of chemokines, pro-inflammatory cytokines and mediators, and various adhesion proteins and molecules. In the mouse, mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is selectively expressed on endothelium of high endothelial venules in gut and gut-associated lymphoid tissue. By interaction with its integrin ligand, alpha 4 beta 7, lymphocytes presumed to be involved in mucosal immunity are selectively recruited to these intestinal sites. After generating monoclonal antibodies against a murine cell line expressing recombinant human MAdCAM-1, we qualitatively and semiquantitatively assessed MAdCAM-1 expression in human tissue sections from various normal and inflammatory disorders. We found that human MAdCAM-1, as in the mouse, is expressed in a tissue-selective manner. In normal tissues, MAdCAM-1 is constitutively expressed to endothelium of venules of intestinal lamina propria. Interestingly, using computer-assisted morphometric analysis, the proportion of venular endothelium within lamina propria that expresses MAdCAM-1 is increased, compared with normal tissues, at inflammatory foci associated with ulcerative colitis and Crohn's disease. Moreover, for the most part, MAdCAM-1 is not detected in the majority of normal or inflamed extra-intestinal tissues, including those with mucosal surfaces. These results are consistent with a role, as originally defined in the mouse, for human MAdCAM-1 in the localization of alpha 4 beta 7+ lymphocytes in the gastrointestinal tract and associated lymphoid tissue. As such, the pathway defined by MAdCAM-1/alpha 4 beta 7 may be a relevant tissue-specific therapeutic target for the modulation of inflammatory bowel disease activity. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9212736
Association between the Polymorphisms in Intercellular Adhesion Molecule-1 and the Risk of Coronary Atherosclerosis: A Case-Controlled Study
Zhang, Qingjiang; Xin, Yu; Chen, Yanjun; Tian, Ye
Intercellular adhesion molecule-1 (ICAM-1), an important immune adhesion molecule, is related to the atherosclerosis. We explored the association between the polymorphisms of the ICAM-1 gene and coronary atherosclerotic stenosis to determine whether any risk factors correlate with genetic polymorphisms in Chinese patients with coronary atherosclerosis. Using the SNaPshot assay, we examined six SNPs of rs5491, rs281428, rs281432, rs5496, rs5498 and rs281437 in 604 patients diagnosed with coronary atherosclerotic stenosis by angiography and in 468 controls. We found that AG genotype of rs5498 had higher frequency in the coronary atherosclerotic stenosis patients (41.56% to 34.19%, P?=?0.017, OR?=?1.368,95%CI 1.057¢1.770) and that the haplotype Ars5491Crs281428Grs281432 had higher frequency in patients (13.8% to 12.1%, P?=?0.048). When analyzing the clinical risk factors for coronary atherosclerosis, we found that the rs5498 locus was associated with the levels of apolipoprotein A (APOA) (P?=?0.0002) and triglycerides (TG) (P?=?0.002). Furthermore, the levels of triglycerides (TG) were also associated with rs281432 (P?=?0.040). Additionally, the TT genotype of rs281437 was associated with a higher level of apolipoprotein A (APOA) (P?=?0.039) and apolipoprotein B (APOB) (P?=?0.003). Finally, among those with coronary atherosclerosis, we found no differences in the haplotype analysis of polymorphisms of the ICAM-1 gene from individuals with hypertension or those who smoked. According to our results, the ICAM-1 polymorphisms were associated with risk of coronary atherosclerotic stenosis in Chinese individuals. PMID:25310099
Nitric Oxide-Enhanced Molecular Imaging of Atheroma using Vascular Cellular Adhesion Molecule 1-Targeted Echogenic Immunoliposomes.
Kim, Hyunggun; Kee, Patrick H; Rim, Yonghoon; Moody, Melanie R; Klegerman, Melvin E; Vela, Deborah; Huang, Shao-Ling; McPherson, David D; Laing, Susan T
The aim of this study was to determine whether pre-treatment with nitric oxide-loaded echogenic liposomes (NO-ELIP) plus ultrasound can improve highlighting by molecularly targeted (anti-vascular cell adhesion molecule 1 [VCAM-1]) ELIP of atheroma components. Atherosclerotic animals were treated with anti-VCAM-1-ELIP or immunoglobulin (IgG)-ELIP. Each group was selected at random to receive pre-treatment with standard ELIP plus ultrasound, NO-ELIP without ultrasound and NO-ELIP plus ultrasound. Intravascular ultrasound highlighting data for the same arterial segments were collected before and after treatment. Pre-treatment with NO-ELIP plus ultrasound resulted in a significant increase in acoustic enhancement by anti-VCAM-1-ELIP (21.3 ▒ 1.5% for gray-scale value, 53.9 ▒ 3.1% for radiofrequency data; p < 0.001 vs. IgG-ELIP, p < 0.05 vs. pre-treatment with standard ELIP plus ultrasound or NO-ELIP without ultrasound). NO-ELIP plus ultrasound can improve highlighting of atheroma by anti-VCAM-1 ELIP. This NO pre-treatment strategy may be usefulĀinĀoptimizing contrast agent delivery to the vascular wall for both diagnostic and therapeutic applications. PMID:25819469
Immunologic changes in TNF-alpha, sE-selectin, sP-selectin, sICAM-1, and IL-8 in pediatric patients treated for psoriasis with the Goeckerman regimen
Borska, L.; Fiala, Z.; Krejsek, J.; Andrys, C.; Vokurkova, D.; Hamakova, K.; Kremlacek, J.; Ettler, K. [Charles University of Prague, Hradec Kralove (Czech Republic). Faculty of Medicine
Psoriasis is a chronic inflammatory skin disease which is often manifested during childhood. The present study investigated changes in the serum levels of proinflammatory cytokines and soluble forms of adhesion molecules in children with psoriasis. The observed patient group of 26 children was treated with the Goeckerman regimen. This therapy combines dermal application of crude coal tar with ultraviolet radiation. The Psoriasis Area Severity Index decreased significantly after treatment by with the Goeckerman regimen (p < 0.001). Serum levels of the proinflammatory cytokine TNF-alpha and adhesion molecules sICAM-1, sP-selectin and sE-selectin decreased after the Goeckerman regimen. The TNF-alpha and sICAM-1 decreased significantly (p < 0.05). Our findings support the complex role of these immune parameters in the immunopathogenesis of psoriasis in children. The serum level of IL-8 increased after the Goeckerman regimen. This fact indicates that the chemokine pathway of IL-8 activity could be modulated by this treatment, most likely by polycyclic aromatic hydrocarbons.
Platelet endothelial cell adhesion molecule?1 gene 125C/GĀpolymorphism is associated with deep vein thrombosis.
Li, Gang; Han, Zong-Lin; Dong, He-Gui; Zhang, Xia; Kong, Xiang-Qian; Jin, Xing
Deep vein thrombosis (DVT) is a common disorder that is associated with high morbidity and mortality. Genetic factors have been suggested to influence the predisposition towards thrombosis and the incidence of DVT. Platelet endothelial cell adhesion molecule?1 (PECAM?1) is a key adhesion molecule that is involved in platelet function and maintenance of endothelial cell junctions. To date, no studies have examined the association between polymorphisms in PECAM?1 and DVT. The present study analyzed the single nucleotide polymorphisms (SNPs) of PECAM?1, namely Leu125ValĀ(C373G), Asn563SerĀ(T1688C) and Gly670ArgĀ(C2008T), in Chinese patients with DVT and age? and gender?matched controls, using polymerase chain reaction?restriction fragment length polymorphism analysis. Furthermore, plasma soluble PECAM?1 (sPECAM?1) levels were quantified by ELISA. The results of the present study demonstrated significantly higher genotype and allele frequencies of the Leu125Val polymorphism in PECAM?1 in the DVT group as compared with those in the control group (P<0.05). The plasma levels of sPECAM?1 in the DVT group (83.4▒23.5Āng/ml) were also significantly higher as compared with those in the control group (60.4▒19.4Āng/ml, P<0.01). In the patients with DVT, plasma levels of sPECAM?1 were significantly higher in those with the Leu/Val and Val/Val genotypes as compared with those possessing the Leu/Leu genotype (P<0.05). The PECAM?1 Leu125Val polymorphism was shown to be associated with an increased risk of DVT and PECAM?1 protein expression levels in venous vessels. In patients with DVT, the PECAM?1 Leu/Val and Val/Val genotypes were associated with delayed thrombus resolution, as determined by thrombus scoring, as compared with that in patients possessing the Leu/Val genotype. In conclusion, the present study indicated that PECAM?1 Leu125Val polymorphism and sPECAM?1 levels may be associated with DVT. PMID:25846278
Induction of human macrophage vascular endothelial growth factor and intercellular adhesion molecule-1 by Ureaplasma urealyticum and downregulation by steroids.
Li, Ying-Hua; Brauner, Annelie; Jensen, J°rgen Skov; Tullus, Kjell
Chronic lung disease (CLD) remains a major cause of morbidity for the prematurely born infant. The pathogenesis of CLD is complex and has not been defined entirely. Infection and lung inflammatory events have been thought to play a key role in the development of CLD. However, the contribution of Ureaplasma urealyticum to the development of CLD is debated and steroids produce some improvement in neonates with this disease. The aim of this study was to investigate if U. urealyticum could stimulate macrophages to produce vascular endothelial growth factor (VEGF) and intercellular adhesion molecule-1 (ICAM-1) in vitro, which are potentially associated with both early and later pathological changes in the lung during the development of CLD. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (>/=4 x 10(7) color-changing units/ml) stimulated human macrophages (phorbol 12-myristate 13-acetate-differentiated THP-1 cell line) to produce VEGF and soluble ICAM-1 in a dose-dependent manner (p < 0.05) measured by ELISA. Likewise, cell surface ICAM-1 (CD54) measured by flow cytometry was increased after stimulation with U. urealyticum. This effect was attenuated by budesonide and dexamethasone (p < 0.05). The mRNA expressions of VEGF and ICAM-1 detected by a semi-quantitative reverse transcriptase polymerase chain reaction were also induced in response to U. urealyticum and inhibited by the steroids (p < 0.05). The expression of ICAM-1 was reduced by 85.5% when the TNF-alpha production was neutralized with an anti-TNF-alpha antibody. Our findings imply that U. urealyticum might be involved in the development of CLD of prematurity. PMID:12119537
Plasma zinc levels inversely correlate with vascular cell adhesion molecule-1 concentration in children with sickle cell disease.
Kuvibidila, Solo R.; Sandoval, Manuel; Lao, Juan; Velez, Maria; Yu, Lolie; Ode, David; Gardner, Renķe; Lane, Gerald; Warrier, Raj P.
Zinc deficiency has been implicated in impaired cell-mediated immunity of children with sickle cell disease (SCD). However, its influence on the expression of vascular cell-adhesion molecule-1 (VCAM-1) on endothelial cells, a protein involved in vasoocclusion, has not been previously investigated. We therefore measured (soluble) sVCAM-1 and zinc in 76 SCD children and 96 non-SCD children, mean age 7.73 years and 11.24 years, respectively. Although mean zinc levels of both groups were within the normal range (approximately 14.5 micromol/l), 14.5 % of SCD and 11% of non-SCD children (without inflammation) had levels below normal (10.7 micromol/L). Mean sVCAM-1 concentrations of SCD children (837 microg/l) were significantly higher than those of controls (627 microg/l) (p < 0.001). Differences persisted after taking into account age, hemoglobin phenotype, and inflammation (alpha-l acid glycoprotein >l g/l and C-reactive protein >10 mg/I). sVCAM-1 negatively correlated with serum (r = -0.444) and red blood cells zinc (r = -0.242, p < 0.05) but not with acute-phase proteins. Mean sVCAM-1 tended to be higher in SCD children with than in those without a history of a health problem (infection, pain crisis or were transfused; not significant). Data suggest that zinc may modulate the clinical status of SCD children through VCAM-1 expression, and zinc supplementation may be beneficial in these patients. PMID:16916123
Photocarcinogenesis and inhibition of intercellular adhesion molecule 1 expression in cells of DNA-repair-defective?individuals
Ahrens, Constanze; Grewe, Markus; Berneburg, Mark; Grether-Beck, Susanne; Quilliet, Xavier; Mezzina, Mauro; Sarasin, Alain; Lehmann, Alan R.; Arlett, Colin F.; Krutmann, Jean
Cells from patients with xeroderma pigmentosum complementation group D (XP-D) and most patients with trichothiodystrophy (TTD) are deficient in excision repair of ultraviolet (UV) radiation-induced DNA damage. Although in both syndromes this defect is based on mutations in the same gene, XPD, only XP-D, not TTD, individuals have an increased risk of skin cancer. Since the reduction in DNA repair capacity is similar in XP-D and TTD patients, it cannot account for the difference in skin cancer risk. The features of XP-D and TTD might therefore be attributable to differences in the immune response following UV-irradiation, a factor which is presumed to be important for photocarcinogenesis. We have measured the capacity of UVB radiation to inhibit expression of the immunological key molecule intercellular adhesion molecule 1 (ICAM-1) in cells from three healthy individuals in comparison to cells from three XP-D and three TTD patients. Cells from XP-D patients, but not from TTD patients, exhibited an increased susceptibility to UVB radiation-induced inhibition of ICAM-1 expression. Transfection of XP-D cells with the wild-type XPD cDNA, but not with XPC cDNA, corrected this abnormal phenotype. Thus, the skin cancer risk in DNA repair-defective individuals correlated with the susceptibility of their cells to UVB radiation-induced inhibition of ICAM-1 expression, rather than with their defect in DNA repair. The XPD protein has dual roles: in DNA repair and transcription. The transcriptional role might be important for the control of expression of immunologically relevant genes and thereby contribute to the skin cancer risk of a DNA-repair-deficient individual. PMID:9192652
Prognostic prediction and diagnostic role of intercellular adhesion molecule-1 (ICAM1) expression in clear cell renal cell carcinoma.
Shi, Xuebing; Jiang, Jifa; Ye, Xiaobing; Liu, Yanyan; Wu, Qiong; Wang, Lu
The intercellular adhesion molecule-1 (ICAM1) has been reported to function in multiple malignancies, but its effect on clear cell renal cell carcinoma (ccRCC) hasn't been discussed yet. This study aimed to identify the potential role of ICAM1 in prognostic prediction and early diagnosis of ccRCC. ICAM1 expression was inspected by immunohistochemistry and correlated with clinicopathologic variables. Association between protein expression and cancer-specific survival (CSS) of ccRCC patients was evaluated and the value of area under the receiver operating characteristics (ROC) curve (AUC) was calculated to measure the protein's diagnostic accuracy. ICAM1 was positively immunostained in 83.2% of 173 ccRCC tissues, but negatively immunostained in all the para-cancerous normal epitheliums of renal tubules. High ICAM1 expression was significantly related to male sex (P = 0.00241), T3/T4 stage (P = 0.02249), non-N0M0 stage (P = 0.03797) and positive renal pelvis invasion (P = 0.04227). Kaplan-Meier survival analysis illustrated that high ICAM1 expression was significantly correlated to a decreased CSS (P = 0.00006). Multivariate Cox analysis indicated that ICAM1 was an independent predictor for CSS of patients (P = 0.00451). Furthermore, the AUC value of ICAM1 in diagnosing ccRCC was 0.916 (P < 0.00001). In conclusion, high ICAM1 expression on tumor cells indicates a poor outcome of patients and ICAM1 is likely to be an independent predictor for the prognosis of ccRCC. Moreover, ICAM1 has a high AUC value and may be a potential and useful diagnostic marker. PMID:24535541
T-Lymphocyte Responsiveness in Murine Schistosomiasis Mansoni Is Dependent upon the Adhesion Molecules Intercellular Adhesion Molecule1, Lymphocyte Function-Associated Antigen1, and Very Late Antigen4
Granuloma formation in murine schistosomiasis is dependent on CD4 1 Th lymphocytes and requires recruitment and accumulation of inflammatory cells at the site of egg deposition. The present study examined the role of three adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), lymphocyte function- associated antigen-1 (LFA-1), and very late antigen-4 (VLA-4), that participate in cellular recruitment, interaction, and lymphocyte activation during
Kinin B1 receptor regulates interactions between neutrophils and endothelial cells by modulating the levels of Mac-1, LFA-1 and intercellular adhesion molecule-1.
Figueroa, Carlos D; Matus, Carola E; Pavicic, Francisca; Sarmiento, Jose; Hidalgo, Maria A; Burgos, Rafael A; Gonzalez, Carlos B; Bhoola, Kanti D; Ehrenfeld, Pamela
Kinins are pro-inflammatory peptides that mimic the cardinal features of inflammation. We examined the concept that expression levels of endothelial intercellular adhesion molecule-1 (ICAM-1) and neutrophil integrins Mac-1 and LFA-1 are modulated by the kinin B1 receptor (B1R) agonist, Lys-des[Arg(9)]bradykinin (LDBK). Stimulation of endothelial cells with LDBK increased the levels of ICAM-1 mRNA transcripts/protein, and also of E-selectin and platelet endothelial adhesion molecule-1. ICAM-1 levels increased in a magnitude comparable with that produced by TNF-?. This stimulatory effect was reduced when endothelial cells, which had been previously transfected with a B1R small interfering RNA, were stimulated with LDBK, under comparable conditions. Similarly, LDBK produced a significant increase in protein levels of LFA-1 and Mac-1 integrins in human neutrophils, an effect that was reversed by pretreatment of cells with 10?Ąg/ml cycloheximide or a B1R antagonist. Functional experiments performed with post-confluent monolayers of endothelial cells stimulated with LDBK and neutrophils primed with TNF-?, and vice versa, resulted in enhanced adhesiveness between both cells. Neutralizing Abs to ICAM-1 and Mac-1 reduced the adhesion between them. Our results indicate that kinin B1R is a novel modulator that promotes adhesion of leukocytes to endothelial cells, critically enhancing the movement of neutrophils from the circulation to sites of inflammation. PMID:24728914
Contribution of Intercellular-Adhesion Molecule1 in Allergen-Induced Airway Hyperresponsiveness and Inflammation in Sensitised Brown-Norway Rats
J. Sun; W. Elwood; A. Haczku; P. J. Barnes; P. G. Hellewell; K. F. Chung
We investigated the potential role of intercellular-adhesion molecule-1 (ICAM-1) in allergen-induced bronchial hyperresponsiveness (BHR) and inflammation in sensitised Brown-Norway rats. Rats were sensitised with ovalbumin (OA) intraperitoneally and 21 days later they were either exposed to 0.9% NaCl or 1% OA aerosol for 15min. Rats exposed to OA aerosol were pretreated either with ICAM-1 antibody (3 mg\\/kg i.p. and i.v,
Identification of Fer Tyrosine Kinase Localized on Microtubules as a Platelet Endothelial Cell Adhesion Molecule1 Phosphorylating Kinase in Vascular Endothelial Cells
Naoko Kogata; Michitaka Masuda; Yuji Kamioka; Akiko Yamagishi; Akira Endo; Masato Okada; Naoki Mochizuki
Platelet endothelial adhesion molecule-1 (PECAM-1) is a part of intercellular junctions and triggers intracellular signaling cascades upon homophilic binding. The intracellular domain of PECAM-1 is tyrosine phosphorylated upon homophilic engagement. However, it remains unclear which tyrosine kinase phosphorylates PECAM-1. We sought to isolate tyrosine kinases respon- sible for PECAM-1 phosphorylation and identified Fer as a candidate, based on expression cloning.
Cross-linking of Intercellular Adhesion Molecule1 Induces Interleukin8 and RANTES Production through the Activation of MAP Kinases in Human Vascular Endothelial Cells
Hideki Sano; Noriaki Nakagawa; Ryuichi Chiba; Kazuhiro Kurasawa; Yasushi Saito; Itsuo Iwamoto
We investigated whether intercellular adhesion molecule-1 (ICAM-1) transduces outside-in signals for the production of chemokines IL-8 and RANTES in endothelial cells. Cross-linking of ICAM-1 induced IL-8 and RANTES mRNA expressions and increased their protein synthesis and secretions in endothelial cells. Furthermore, ICAM-1 cross-linking activated 44- and 42-kDa mitogen-activated protein (MAP) kinases (ERK1 and ERK2) in endothelial cells, as indicated by
An anti-platelet-endothelial cell adhesion molecule-1 antibody inhibits leukocyte extravasation from mesenteric microvessels in vivo by blocking the passage through the basement membrane
M. W. Wakelin; M.-J. Sanz; A. Dewar; S. M. Albelda; S. W. Larkin; N. Boughton-Smith; T. J. Williams; S. Nourshargh
Summary Platelet-endothelial cell adhesion molecule-1 (PECAM-1, CD31) plays an active role in the process of leukocyte migration through cultured endothelial cells in vitro and anti-PECAM-1 antibodies (Abs) inhibit accumulation ofleukocytes into sites of inflammation in vivo. Despite the latter, it is still not clear at which stage of leukocyte emigration in vivo PECAM-1 is in- volved. To address this point
Anionic Peptide Factor\\/Phosphatidylcholine Particles Promote the Inhibition of Vascular Cell Adhesion Molecule1 in Human Umbilical Vein Endothelial Cells
Elise Lombard; Valķrie Marin; Nicole Domingo; Sandra GrĶs; Anne-Marie Lorec; Vincent Saunier; Emmanuelle Arlotto; Henri Portugal; Denis Lairon; Catherine Farnarier; Franńoise Chanussot
Objective: High-density lipoproteins (HDLs) have significant cardiovascular benefits by retarding the progression of atherosclerosis. One of the mechanisms is the inhibition by HDLs of the vascular cell adhesion molecule-1 (VCAM-1) expression in endothelial cells. Our objective was to test the effect on VCAM-1 expression by the human umbilical vein endothelial cells (HUVEC) of a minor HDL2 and HDL3 apolipoprotein, the
Plasmodium falciparum Erythrocyte Membrane Protein 1 is a Parasitized Erythrocyte Receptor for Adherence to CD36, Thrombospondin, and Intercellular Adhesion Molecule 1
D. I. Baruch; J. A. Gormley; C. Ma; R. J. Howard; B. L. Pasloske
Adherence of mature Plasmodium falciparum parasitized erythrocytes (PRBCs) to microvascular endothelium contributes directly to acute malaria pathology. We affinity purified molecules from detergent extracts of surface-radioiodinated PRBCs using several endothelial cell receptors known to support PRBC adherence, including CD36, thrombospondin (TSP), and intercellular adhesion molecule 1 (ICAM-1). All three host receptors affinity purified P. falciparum erythrocyte membrane protein 1 (PfEMP1),
Advanced glycation endproducts interacting with their endothelial receptor induce expression of vascular cell adhesion molecule-1 (VCAM-1) in cultured human endothelial cells and in mice. A potential mechanism for the accelerated vasculopathy of diabetes.
Schmidt, A M; Hori, O; Chen, J X; Li, J F; Crandall, J; Zhang, J; Cao, R; Yan, Shirley ShiDu; Brett, J; Stern, D
Vascular cell adhesion molecule-1 (VCAM-1), an inducible cell-cell recognition protein on the endothelial cell surface (EC), has been associated with early stages of atherosclerosis. In view of the accelerated vascular ...
Ganoderma lucidum polysaccharides attenuate endotoxin-induced intercellular cell adhesion molecule-1 expression in cultured smooth muscle cells and in the neointima in mice.
Lin, Ching-Yuang; Chen, Yung-Hsiang; Lin, Chia-Ying; Hsu, Hsien-Yeh; Wang, Shu-Huei; Liang, Chan-Jung; Kuan, I-I; Wu, Pei-Jhen; Pai, Pei-Ying; Wu, Chau-Chung; Chen, Yuh-Lien
The expression of adhesion molecules on vessels and subsequent leukocyte recruitment are critical events in vascular diseases and inflammation. The aim of the present study was to examine the effects of an extract of Ganoderma lucidum (Reishi) polysaccharides (EORP), which is effective against cancer and immunological disorders, on adhesion molecule expression by human aortic smooth muscle cells (HASMCs) and the underlying mechanism. EORP significantly suppressed lipopolysaccharide (LPS)-induced intercellular cell adhesion molecule-1 (ICAM-1) mRNA and protein expression and reduced the binding of human monocytes to LPS-stimulated HASMCs. Immunoprecipitation and real-time polymerase chain reaction demonstrated that EORP markedly reduced the interaction of human antigen R protein (HuR) with the 3'-UTR of ICAM-1 mRNA in LPS-stimulated HASMCs. EORP treatment also suppressed extracellular signal-regulated kinase (ERK) phosphorylation and reduced the density of the shifted bands of nuclear factor (NF)-kappaB after LPS-induced activation. In an endothelial-denuded artery model in LPS-treated mice, daily oral administration of EORP for 2 weeks decreased neointimal hyperplasia and ICAM-1 expression in the plasma and neointima. These results provide evidence that EORP attenuates LPS-induced adhesion molecule expression and monocyte adherence and that this protective effect is mediated by decreased ERK phosphorylation and NF-kappaB activation. These findings suggest that EORP has anti-inflammatory properties and could prove useful in the prevention of vascular diseases and inflammatory responses. PMID:20687608
Magnolol reduced TNF-?-induced vascular cell adhesion molecule-1 expression in endothelial cells via JNK/p38 and NF-?B signaling pathways.
Liang, Chan-Jung; Lee, Chiang-Wen; Sung, Hsin-Ching; Chen, Yung-Hsiang; Wang, Shu-Huei; Wu, Pei-Jhen; Chiang, Yao-Chang; Tsai, Jaw-Shiun; Wu, Chau-Chung; Li, Chi-Yuan; Chen, Yuh-Lien
Expression of cell adhesion molecules by the endothelium and the attachment of leukocytes to these cells play major roles in inflammation and cardiovascular disorders. Magnolol, a major active component of Magnolia officinalis, has antioxidative and anti-inflammatory properties. In the present study, the effects of magnolol on the expression of vascular cell adhesion molecule-1 (VCAM-1) in human aortic endothelial cells (HAECs) and the related mechanisms were investigated. TNF-? induced VCAM-1 protein expression and mRNA stability were significantly decreased in HAECs pre-treated with magnolol. Magnolol significantly reduced the phosphorylation of ERK, JNK, and p38 in TNF-?-treated HAECs. The decrease in VCAM-1 expression in response to TNF-? treatment was affected by JNK and p38 inhibitors, not by an ERK inhibitor. Magnolol also attenuates NF-?B activation and the translocation of HuR (an RNA binding protein) in TNF-?-stimulated HAECs. The VCAM-1 expression was weaker in the aortas of TNF-?-treated apo-E deficient mice with magnolol treatment. These data demonstrate that magnolol inhibits TNF-?-induced JNK/p38 phosphorylation, HuR translocation, NF-?B activation, and thereby suppresses VCAM-1 expression resulting in reduced leukocyte adhesion. Taken together, these results suggest that magnolol has an anti-inflammatory property and may play an important role in the prevention of atherosclerosis and inflammatory responses. PMID:24871655
Cerivastatin ameliorates high insulin-enhanced neutrophil¢endothelial cell adhesion and endothelial intercellular adhesion molecule-1 expression by inhibiting mitogen-activated protein kinase activation
Masahiro Okouchi; Naotsuka Okayama; Hitoshi Omi; Kenro Imaeda; Manabu Shimizu; Tatsuya Fukutomi; Makoto Itoh
Background and aimThere is growing evidence that hyperinsulinemia is linked to the development of atherosclerosis in patients with diabetes. We demonstrated previously that high insulin exacerbates neutrophil¢endothelial cell adhesion and endothelial intercellular adhesion molecule (ICAM)-1 expression through activation of protein kinase C (PKC) and mitogen-activated protein (MAP) kinase. Though 3-hydroxymethyl-3-glutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been employed as
SNPs in the neural cell adhesion molecule 1 gene ( NCAM1 ) may be associated with human neural tube defects
Kristen L. Deak; Abee L. Boyles; Heather C. Etchevers; Elizabeth C. Melvin; Deborah G. Siegel; Felicia L. Graham; Susan H. Slifer; David S. Enterline; Timothy M. George; Michel Vekemans; David McClay; Alexander G. Bassuk; John A. Kessler; Elwood Linney; John R. Gilbert; Marcy C. Speer
Neural tube defects (NTDs) are common birth defects, occurring in approximately 1\\/1,000 births; both genetic and environmental factors are implicated. To date, no major genetic risk factors have been identified. Throughout development, cell adhesion molecules are strongly implicated in cell¢cell interactions, and may play a role in the formation and closure of the neural tube. To evaluate the role of
Rapid detection of intercellular adhesion molecule 1 (G241R and K469E) polymorphisms by a novel PCR-SSP assay.
Tajik, N; Salari, F; Hajilooi, M; Amoli, M; Salekmoghaddam, A
Intercellular adhesion molecule 1 (ICAM-1) is a cell surface glycoprotein member of the immunoglobulin superfamily and is actively involved in immune and inflammatory responses. We introduce a novel polymerase chain reaction-sequence-specific primers (PCR-SSP) method for rapid and simultaneous genotyping of ICAM-1 G241R and K469E polymorphisms. In a total of 184 DNA samples that have been previously analyzed for these polymorphisms using polymerase chain reaction-restriction fragment length polymorphism technique, re-genotyping of all samples with this new assay showed accurate and reproducible results. As PCR-SSP-based genotyping protocols are more convenient and cost-effective to do, it could therefore offer a valuable tool for assessment of ICAM-1 polymorphisms to which more confirmatory studies are needed. PMID:17389018
Protein production, crystallization and preliminary crystallographic analysis of the four N-terminal immunoglobulin domains of Down syndrome cell adhesion molecule 1.
Cheng, Linna; Li, Shu Ang; Yu, Yamei; Chen, Qiang
Down syndrome cell adhesion molecule 1 (Dscam1), a member of the immunoglobulin (Ig) superfamily, plays important roles in both the nervous and the immune systems. Via alternative RNA splicing, Drosophila Dscam1 encodes a vast family of Ig-containing proteins that exhibit isoform-specific homophilic binding. Whether different Dscam1 isoforms adopt the same dimerization mode is under debate, and the detailed mechanism of Dscam1 specificity remains unclear. In this study, eight different isforms of Dscam1 Ig1-4 have been cloned, overexpressed, purified to homogeneity and crystallized. X-ray data were collected to 1.9-4.0?┼ resolution. These structures will provide the opportunity to perform extensive structural comparisons of different Dscam1 isoforms and provide insight into its specificity. PMID:26057811
Adhesion of Monocyte Very Late Antigen4 to Endothelial Vascular Cell Adhesion Molecule1 Induces Interleukin1b-Dependent Expression of Interleukin6 in Endothelial Cells
Dietlind Zohlnhofer; Korbinian Brand; Katharina Schipek; Gisela Pogatsa-Murray; Albert Schomig; Franz-Josef Neumann
In atheroma, T cell- derived interferon- g (INF-g) stimulates endothelial cells and facilitates recruitment of monocytes. We investigated potential mechanisms by which these interactions could contribute to local and systemic inflammatory responses. Specifically, we analyzed the expression of interleukin (IL)-1 b and IL-6 in both cell types after coculture, the relevant adhesion molecules in this interaction, and transcriptional control by
Dileucine and PDZ-binding Motifs Mediate Synaptic Adhesion-like Molecule 1 (SALM1) Trafficking in Hippocampal Neurons*
Seabold, Gail K.; Wang, Philip Y.; Petralia, Ronald S.; Chang, Kai; Zhou, Arthur; McDermott, Mark I.; Wang, Ya-Xian; Milgram, Sharon L.; Wenthold, Robert J.
Synaptic adhesion-like molecules (SALMs) are a family of cell adhesion molecules involved in neurite outgrowth and synapse formation. Of the five family members, only SALM1, -2, and -3 contain a cytoplasmic C-terminal PDZ-binding motif. We have found that SALM1 is unique among the SALMs because deletion of its PDZ-binding motif (SALM1?PDZ) blocks its surface expression in heterologous cells. When expressed in hippocampal neurons, SALM1?PDZ had decreased surface expression in dendrites and the cell soma but not in axons, suggesting that the PDZ-binding domain may influence cellular trafficking of SALMs to specific neuronal locations. Endoglycosidase H digestion assays indicated that SALM1?PDZ is retained in the endoplasmic reticulum (ER) in heterologous cells. However, when the entire C-terminal tail of SALM1 was deleted, SALM1 was detected on the cell surface. Using serial deletions, we identified a region of SALM1 that contains a putative dileucine ER retention motif, which is not present in the other SALMs. Mutation of this DXXXLL motif allowed SALM1 to leave the ER and enhanced its surface expression in heterologous cells and neurons. An increase in the number of protrusions at the dendrites and cell body was observed when this SALM1 mutant was expressed in hippocampal neurons. With electron microscopy, these protrusions appeared to be irregular, enlarged spines and filopodia. Thus, enrichment of SALM1 on the cell surface affects dendritic arborization, and intracellular motifs regulate its dendritic versus axonal localization. PMID:22174418
Possible mechanism of the anti-inflammatory activity of ruscogenin: role of intercellular adhesion molecule-1 and nuclear factor-kappaB.
Huang, Ya-Lin; Kou, Jun-Ping; Ma, Li; Song, Jia-Xi; Yu, Bo-Yang
Ruscogenin (RUS), first isolated from Ruscus aculeatus, also a major steroidal sapogenin of traditional Chinese herb Radix Ophiopogon japonicus, has been found to exert significant anti-inflammatory and anti-thrombotic activities. Our previous studies suggested that ruscogenin remarkably inhibited adhesion of leukocytes to a human umbilical vein endothelial cell line (ECV304) injured by tumor necrosis factor-alpha (TNF-alpha) in a concentration-dependent manner. Yet the underlying mechanisms remain unclear. In this study, the in vivo effects of ruscogenin on leukocyte migration and celiac prostaglandin E(2) (PGE(2)) level induced by zymosan A were studied in mice. Furthermore, the effects of ruscogenin on TNF-alpha-induced intercellular adhesion molecule-1 (ICAM-1) expression and nuclear factor-kappaB (NF-kappaB) activation were also investigated under consideration of their key roles in leukocyte recruitment. The results showed that ruscogenin significantly suppressed zymosan A-evoked peritoneal total leukocyte migration in mice in a dose-dependent manner, while it had no obvious effect on PGE(2) content in peritoneal exudant. Ruscogenin also inhibited TNF-alpha-induced over expression of ICAM-1 both at the mRNA and protein levels and suppressed NF-kappaB activation considerably by decreasing NF-kappaB p65 translocation and DNA binding activity. These findings provide some new insights that may explain the possible molecular mechanism of ruscogenin and Radix Ophiopogon japonicus for the inhibition of endothelial responses to cytokines during inflammatory and vascular disorders. PMID:18946195
Modulation of tight junction barrier function by outer membrane proteins of enteropathogenic Escherichia coli: role of F-actin and junctional adhesion molecule-1.
Puthenedam, Manjula; Williams, Peter H; Lakshmi, B S; Balakrishnan, Arun
Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea. In this work we investigated the effect of outer membrane proteins (OMP) of EPEC on barrier integrity and the role of actin, junctional adhesion molecule (JAM) and signaling pathways contributing to these changes. Barrier function was assessed by transepithelial electrical resistance (TER). OMP of wild type EPEC, eaeA and maltoporin mutants decreased TER levels of Caco-2 cells. The OMP of espB mutant was deficient in decreasing TER of Caco-2 cells. The proteinase K-digested wild type OMP and EAF mutant OMP did not cause any change in barrier function. Our previous studies have demonstrated that EPEC OMP induced changes in cadherin junctions of Caco-2 cells. Immunofluorescence revealed disruption in actin cytoskeleton by EPEC OMP. However, no change in expression of junctional adhesion molecule-1 was observed. NF-kappaB inhibitor slightly blocked the decrease in TER and protected against actin disruption while ERK1/2 inhibitor had no effect in blocking these changes. In conclusion, our data suggest that the OMP of EPEC alter intestinal barrier function by disrupting actin cytoskeleton and signaling pathways like NF-kappaB may have a role in regulating barrier changes. PMID:17382565
Artemether Combined with shRNA Interference of Vascular Cell Adhesion Molecule-1 Significantly Inhibited the Malignant Biological Behavior of Human Glioma Cells
Wang, Ping; Xue, Yi-Xue; Yao, Yi-Long; Yu, Bo; Liu, Yun-Hui
Artemether is the derivative extracted from Chinese traditional herb and originally used for malaria. Artemether also has potential therapeutic effects against tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we investigated the role and mechanism of artemether combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion and apoptosis of glioma cells. U87 human glioma cells were treated with artemether at various concentrations and shRNA interfering technology was employed to silence the expression of VCAM-1. Cell viability, migration, invasiveness and apoptosis were assessed with MTT, wound healing, Transwell and Annexin V-FITC/PI staining. The expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and phosphorylated Akt (p-Akt) was checked by Western blot assay. Results showed that artemether and shRNA-VCAM-1 not only significantly inhibited the migration, invasiveness and expression of MMP-2/9 and p-Akt, but also promoted the apoptosis of U87 cells. Combined treatment of both displayed the maximum inhibitory effects on the malignant biological behavior of glioma cells. Our work revealed the potential therapeutic effects of artemether and antiVCAM-1 in the treatments of gliomas. PMID:23593320
Recruitment of lymphocytes during cutaneous delayed hypersensitivity in nonhuman primates is dependent on E-selectin and vascular cell adhesion molecule 1.
Silber, A; Newman, W; Sasseville, V G; Pauley, D; Beall, D; Walsh, D G; Ringler, D J
Previous investigations of cutaneous delayed hypersensitivity (DHR) in humans and animals have demonstrated that lymphocyte recruitment from blood is temporally and spatially associated with the de novo, asynchronous expression of both vascular cell adhesion molecule 1 (VCAM-1) and E-selectin on dermal endothelium. In this study, DHR was induced in rhesus monkeys sensitized against tuberculin in order to investigate the contribution of E-selectin and VCAM-1 in lymphocyte recruitment to skin. Intravenous infusions of neutralizing doses of F(ab')2 fragments of murine antibodies to either E-selectin or VCAM-1 during the early inductive phases of DHR showed that murine IgG localized to dermal endothelium at the site of DHR in a pattern kinetically similar to the expression of each endothelial adhesion protein. Most importantly, the relative numbers of lymphocytes localized to the inflammatory site were significantly reduced in DHR modified with infusions of antibodies to either VCAM-1 or E-selectin, while the numbers of lymphocytes recruited to skin in the animal given F(ab')2 fragments of an irrelevant murine monoclonal antibody of the same isotype and at the same dose were not changed. Moreover, in individual animals, the relative inhibition achieved with a particular antibody was proportional to the magnitude of expression of the targeted adhesion protein. Therefore, both VCAM-1 and E-selectin are functionally relevant in the genesis of cutaneous DHR, and each appears to contribute to lymphocyte recruitment in relation to its relative degree of expression in any one particular animal. Images PMID:7512984
Intercellular adhesion molecule 1/2 and E-selectin in plasma cell mastitis: immunohistochemical study of 35 cases.
Dong, Yu; Yu, Jian-Jun; Shibahara, Yukiko; Lu, Huai-Sheng; He, Hai-Yan; Liu, Jian-Dong; Chen, Shi-Fan; Wang, Lin; Zhang, Ye; Felizola, Saulo J A; Chan, Monica S M; Ono, Katsuhiko; Ishida, Takanori; Ohuchi, Noriaki; Sasano, Hironobu
Plasma cell mastitis (PCM) is one of the most frequently encountered inflammatory diseases of the nonlactating breast. Histologically, PCM is characterized by infiltration of relatively abundant plasma cells into the mammary ducts. Its pathogenesis has remained unknown. In this study, we immunolocalized intercellular adhesion molecule (ICAM) 1 and 2 and E-selectin, all of which play pivotal roles in the inflammatory process, in 35 cases of PCM. We then compared the results with those of non-PCM and nonpathologic breast tissue. In the ductal epithelium, ICAM-1 immunoreactivity was significantly more pronounced in PCM than in non-PCM (P = .045). Both ICAM-1 (P < .001) and ICAM-2 (P = .001) were significantly more pronounced in PCM than in nonpathologic breast tissue. However, no significant differences in ICAM-2 and E-selectin immunoreactivity were detected between ductal epithelium of PCM and non-PCM. ICAM-1, but not ICAM-2 or E-selectin, demonstrated significantly higher immunoreactivity in endothelial cells of PCM than in nonpathologic breast (P < .001). These results all suggest that ICAM-1 in both ductal epithelium and endothelium plays important roles in the inflammatory process of PCM, possibly through margination, extravasation, and attachment of plasma cells and lymphocytes, which may result in continuous inflammatory cell homing to ductal epithelial cells. PMID:24457076
The Interaction Affinity between Vascular Cell Adhesion Molecule-1 (VCAM-1) and Very Late Antigen-4 (VLA-4) Analyzed by Quantitative FRET
Wu, Shu-Han; Karmenyan, Artashes; Chiou, Arthur
Very late antigen-4 (VLA-4), a member of integrin superfamily, interacts with its major counter ligand vascular cell adhesion molecule-1 (VCAM-1) and plays an important role in leukocyte adhesion to vascular endothelium and immunological synapse formation. However, irregular expressions of these proteins may also lead to several autoimmune diseases and metastasis cancer. Thus, quantifying the interaction affinity of the VCAM-1/VLA-4 interaction is of fundamental importance in further understanding the nature of this interaction and drug discovery. In this study, we report an æin solutionÆ steady state organic fluorophore based quantitative fluorescence resonance energy transfer (FRET) assay to quantify this interaction in terms of the dissociation constant (Kd). We have used, in our FRET assay, the Alexa Fluor 488-VLA-4 conjugate as the donor, and Alexa Fluor 546-VCAM-1 as the acceptor. From the FRET signal analysis, Kd of this interaction was determined to be 41.82 ▒ 2.36 nM. To further confirm our estimation, we have employed surface plasmon resonance (SPR) technique to obtain Kd = 39.60 ▒ 1.78 nM, which is in good agreement with the result obtained by FRET. This is the first reported work which applies organic fluorophore based æin solutionÆ simple quantitative FRET assay to obtain the dissociation constant of the VCAM-1/VLA-4 interaction, and is also the first quantification of this interaction. Moreover, the value of Kd can serve as an indicator of abnormal protein-protein interactions; hence, this assay can potentially be further developed into a drug screening platform of VLA-4/VCAM-1 as well as other protein-ligand interactions. PMID:25793408
Activation of intercellular adhesion molecule 1 expression by Helicobacter pylori is regulated by NF-kappaB in gastric epithelial cancer cells.
Mori, N; Wada, A; Hirayama, T; Parks, T P; Stratowa, C; Yamamoto, N
Interactions between leukocytes and epithelial cells may play a key role in Helicobacter pylori-associated gastric mucosal inflammation. This process is mediated by various cell adhesion molecules. The present study examined the molecular mechanisms leading to H. pylori-induced epithelial cell intercellular adhesion molecule-1 (ICAM-1; also called CD54) expression. Coculture of epithelial cells with cytotoxin-associated gene pathogenicity island-positive (cag PAI(+)) H. pylori strains, but not with a cag PAI(-) strain or H. pylori culture supernatants, resulted in upregulation of steady-state mRNA levels and cell surface expression of ICAM-1. Coculture with H. pylori induced an increase in luciferase activity in cells which were transfected with a luciferase reporter gene linked to the 5'-flanking region of the ICAM-1 gene. H. pylori activated the ICAM-1 promoter via the NF-kappaB binding site. An inducible nuclear protein complex bound to the ICAM-1 NF-kappaB site and was identified as the NF-kappaB p50-p65 heterodimer. H. pylori induced the degradation of IkappaB-alpha, a major cytoplasmic inhibitor of NF-kappaB, and stimulated the expression of IkappaB-alpha mRNA. Pretreatment of epithelial cells with pyrrolidine dithiocarbamate, which blocks NF-kappaB activation, inhibited H. pylori-induced ICAM-1 expression. THP-1 macrophagic cells, peripheral blood mononuclear cells, and purified neutrophils adhered to H. pylori-infected epithelial cells to a greater extent than to uninfected cells. These results show that H. pylori directly induces expression of ICAM-1 on gastric epithelial cells in an NF-kappaB-dependent manner that may support leukocyte attachment during inflammation. PMID:10722567
Plasmin induces intercellular adhesion molecule 1 expression in human endothelial cells via nuclear factor-?B/mitogen-activated protein kinases-dependent pathways.
Li, Qun; Syrovets, Tatiana; Simmet, Thomas; Ding, Jiazeng; Xu, Jianzhong; Chen, Wendong; Zhu, Dingliang; Gao, Pingjin
Activation of endothelial cells (ECs) by proinflammatory stimuli triggers expression of cellular adhesion molecules including intercellular adhesion molecule 1 (ICAM-1) on the cell surface. Such molecules mediate the transendothelial migration of inflammatory cells, which is an early key step of atherogenesis. We have previously demonstrated that plasmin activates human inflammatory cells via the annexin A2 heterotetramer (A2t). Here we show that human umbilical vein endothelial cells (HUVECs) and human microvascular endothelial cells express high amounts of A2t, as shown by Western blotting, fluorescence microscopy and flow cytometry. Activation of HUVEC by plasmin led to cleavage of the annexin A2 subunit of the receptor complex, followed by the activation of Akt/nuclear factor (NF)-?B signaling, and phosphorylation of MAP kinases p38 and ERK1/2. Further, plasmin stimulates the NF-?B/p38-dependent expression of ICAM-1 by HUVEC. The plasmin-induced activation of cells was abolished when annexin A2 was down-regulated by small-interfering RNA. In vivo, we show co-localization of the ECs marker CD31 with the plasmin receptor A2t and ICAM-1 in human atherosclerotic plaques of human femoral arteries, which also exhibit activated NF-?B signaling as revealed by immunofluorescence staining for phosphorylated I?B?. In addition, plasma of patients with advanced atherosclerosis exhibited enhanced plasmin activity and up-regulated levels of plasmin-?2-antiplasmin. These data point to a previously unrecognized functional role of plasmin in EC biology, which could be of particular relevance in the development of atherosclerosis. PMID:23576799
Activation of transcription factor AP-2 mediates UVA radiation- and singlet oxygen-induced expression of the human intercellular adhesion molecule 1?gene
Grether-Beck, Susanne; Olaizola-Horn, Sylvia; Schmitt, Heidi; Grewe, Markus; Jahnke, Andreas; Johnson, Judith?P.; Briviba, Karlis; Sies, Helmut; Krutmann, Jean
UVA radiation is the major component of the UV solar spectrum that reaches the earth, and the therapeutic application of UVA radiation is increasing in medicine. Analysis of the cellular effects of UVA radiation has revealed that exposure of human cells to UVA radiation at physiological doses leads to increased gene expression and that this UVA response is primarily mediated through the generation of singlet oxygen. In this study, the mechanisms by which UVA radiation induces transcriptional activation of the human intercellular adhesion molecule 1 (ICAM-1) were examined. UVA radiation was capable of inducing activation of the human ICAM-1 promoter and increasing ICAM-1 mRNA and protein expression. These UVA radiation effects were inhibited by singlet oxygen quenchers, augmented by enhancement of singlet oxygen life-time, and mimicked in unirradiated cells by a singlet oxygen-generating system. UVA radiation as well as singlet oxygen-induced ICAM-1 promoter activation required activation of the transcription factor AP-2. Accordingly, both stimuli activated AP-2, and deletion of the putative AP-2-binding site abrogated ICAM-1 promoter activation in this system. This study identified the AP-2 site as the UVA radiation- and singlet oxygen-responsive element of the human ICAM-1 gene. The capacity of UVA radiation and/or singlet oxygen to induce human gene expression through activation of AP-2 indicates a previously unrecognized role of this transcription factor in the mammalian stress response. PMID:8962096
Association between intercellular adhesion molecule-1 gene K469E polymorphism and the risk of stroke in a Chinese population: a meta-analysis.
Zhang, Ming-Jie; Zhang, Meng; Yin, Yan-Wei; Li, Bing-Hu; Liu, Yun; Liao, Shao-Qiong; Gao, Chang-Yue; Li, Jing-Cheng; Zhang, Li-Li
Several epidemiologic studies have evaluated the association between intercellular adhesion molecule-1 (ICAM-1) gene K469E polymorphism and stroke, but the results were inconsistent. The present meta-analysis was performed to investigate the relationship between K469E polymorphism and stroke in the Chinese population. A comprehensive search for related studies from the electronic databases of PubMed, Embase, Web of Science, CBMdisc and CNKI as well as a manual search of the references of identified articles was performed. Data were extracted to calculate for allelic, additive, dominant and recessive models using pooled odds ratios (ORs) along with 95% confidence intervals (CIs) by Review Manager 5.0 and Stata 11.0. Different effect models, subgroup analysis, sensitivity analysis, publication bias and power calculations were used to improve the comprehensive analysis. Finally, a total of 12 studies containing 1593 cases and 1555 controls were included in the final meta-analysis. No evidence of significant association between ICAM-1 gene K469E polymorphism and stroke was found in all four models (allelic model: OR = 1.07, 95%CI = 0.78-1.47; additive model: OR = 1.21, 95% CI = 0.67-2.16 (EE vs. KK); OR = 1.04, 95%CI = 0.75-1.45 (EK vs. KK); dominant model: OR = 1.07, 95% CI = 0.73-1.56; and recessive model: OR = 1.18, 95% CI = 0.77-1.83, respectively) based on the overall population, as well as subgroup analysis and sensitivity analysis. In conclusion, the present meta-analysis showed no evidence of significant association between ICAM-1 gene K469E polymorphism and stroke in the Chinese population. Nonetheless, this conclusion should be interpreted cautiously due to the low statistical power and considerable heterogeneity. Therefore, larger sample-size studies with homogeneous cases and well-matched controls are needed to further address this correlation. PMID:24785937
Leptin, soluble interleukin-6 receptor, C-reactive protein and soluble vascular cell adhesion molecule-1 levels in human coronary atherosclerotic plaque.
Karaduman, M; Oktenli, C; Musabak, U; Sengul, A; Yesilova, Z; Cingoz, F; Olgun, A; Sanisoglu, S Y; Baysan, O; Yildiz, O; Taslipinar, A; Tatar, H; Kutlu, M; Ozata, M
The aim of the present study was to explore the relationship between tissue levels of leptin, soluble interleukin-6 receptor (sIL-6R), high-sensitive-C-reactive protein (hs-CRP) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in atherosclerotic plaques, and traditional risk factors. Coronary artery specimens were obtained from 35 consecutive patients (26 men and nine women) who underwent coronary artery bypass grafting procedure. The mean tissue levels of leptin, hs-CRP and sIL-6R were significantly higher in patients with diabetes mellitus than without diabetes mellitus. When patients were classified according to the smoking status, the mean tissue levels of leptin, hs-CRP and sIL-6R were significantly higher in current smokers than both former smokers and non-smokers. In addition, the mean tissue levels of leptin and sIL-6R were significantly higher in former smokers than non-smokers. There was a positive association between leptin and hs-CRP, sIL-6R and plasma glucose in all patients. Plasma HDL levels were associated negatively with atherosclerotic tissue levels of leptin. Tissue levels of sIL-6R were associated significantly in a positive manner with leptin, hs-CRP and plasma glucose, while tissue levels of hs-CRP were associated with both leptin and sIL-6R. In conclusion, it is attractive to speculate that hs-CRP, sIL-6R and leptin could act synergistically in course of local inflammatory activity and those molecules may not be just markers of inflammation and cardiovascular risk but are also likely to play a pathogenic role in atheromatous plaque. In addition, atherosclerotic tissue levels of CRP, sIL-6R and leptin were significantly higher in current smokers and patients with diabetes. PMID:16487244
Leptin, soluble interleukin-6 receptor, C-reactive protein and soluble vascular cell adhesion molecule-1 levels in human coronary atherosclerotic plaque
Karaduman, M; Oktenli, C; Musabak, U; Sengul, A; Yesilova, Z; Cingoz, F; Olgun, A; Sanisoglu, S Y; Baysan, O; Yildiz, O; Taslipinar, A; Tatar, H; Kutlu, M; Ozata, M
The aim of the present study was to explore the relationship between tissue levels of leptin, soluble interleukin-6 receptor (sIL-6R), high-sensitive-C-reactive protein (hs-CRP) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in atherosclerotic plaques, and traditional risk factors. Coronary artery specimens were obtained from 35 consecutive patients (26 men and nine women) who underwent coronary artery bypass grafting procedure. The mean tissue levels of leptin, hs-CRP and sIL-6R were significantly higher in patients with diabetes mellitus than without diabetes mellitus. When patients were classified according to the smoking status, the mean tissue levels of leptin, hs-CRP and sIL-6R were significantly higher in current smokers than both former smokers and non-smokers. In addition, the mean tissue levels of leptin and sIL-6R were significantly higher in former smokers than non-smokers. There was a positive association between leptin and hs-CRP, sIL-6R and plasma glucose in all patients. Plasma HDL levels were associated negatively with atherosclerotic tissue levels of leptin. Tissue levels of sIL-6R were associated significantly in a positive manner with leptin, hs-CRP and plasma glucose, while tissue levels of hs-CRP were associated with both leptin and sIL-6R. In conclusion, it is attractive to speculate that hs-CRP, sIL-6R and leptin could act synergistically in course of local inflammatory activity and those molecules may not be just markers of inflammation and cardiovascular risk but are also likely to play a pathogenic role in atheromatous plaque. In addition, atherosclerotic tissue levels of CRP, sIL-6R and leptin were significantly higher in current smokers and patients with diabetes. PMID:16487244
Cholestin ( Monascus purpureus rice) inhibits homocysteine-induced reactive oxygen species generation, nuclear factor-?B activation, and vascular cell adhesion molecule-1 expression in human aortic endothelial cells
Chih-Pei Lin; Yung-Hsiang Chen; Jaw-Wen Chen; Hsin-Bang Leu; Tsan-Zon Liu; Po-Len Liu; Song-Lih Huang
Hyperhomocysteinemia is associated with dysfunction and an independent risk factor of cardiovascular diseases. Cholestin (Monascus purpureus-fermented rice), contains a naturally-occurring statin, which has lipid-modulating and anti-inflammatory effects. We investigated\\u000a the effects of Cholestin extract on the expression of vascular cell adhesion molecule-1 (VCAM-1) by homocysteine (HCY)-treated\\u000a human aortic endothelial cells (HAECs). Supplement of HAECs with Cholestin extract significantly suppressed cellular
Inhibition of Interferon-?-Induced Intercellular Adhesion Molecule1 Expression on Human Keratinocytes by Phosphorothioate Antisense Oligodeomynucleotides Is the Consequence of Antisense-Specific and Antisense-Non-Specific Effects
Michael Hertl; Leonard M. Neckers; Stephen I. Katz
Expression of intercellular adhesion molecule-1 (ICAM-1) by keratinocytes is an important event in the pathogenesis of T-cell-mediated inflammatory skin diseases. To determine if ICAM-1 expression could be selectively modulated, two antisense phosphorothioate oligonucleotides (S-ODN) targeting the translation initiation and 3' untranslated regions of ICAM-1 mRNA were added as lipid complexes to cultures of keratinocytes. Interferon-? was added after 24 h
Evidence that DNA Damage Is a Mediate in Ultraviolet B Radiation-Induced Inhibition of Human Gene Expression: Ultraviolet B Radiation Effects on Intercellular Adhesion Molecule1 (ICAM-1) Expression
Jean Krutmann; Elisabeth Bohnert; Ernst G. Jung
Expression of intercellular adhesion molecule-1 (ICAM-1) is a prerequisite for the capacity of cells to physically interact with leukocytes. Ultraviolet B radiation previously was found to inhibit interferon ?-induced ICAM-1 expression in human keratinocytes by suppressing interferon ?-mediated upregulation of ICAM-1 mRNA levels. Because ultraviolet B radiation induces photoproducts in cellular DNA, the potential role of ultraviolet B radiation-induced DNA
Neonatally induced inactivation of the vascular cell adhesion molecule 1 gene impairs B cell localization and T cell--dependent humoral immune response
Christoph E. Leuker; Mark Labow; Werner M³ller
Vascular cellular adhesion molecule (VCAM)-1 is a membrane-bound cellular adhesion mole- cule that mediates adhesive interactions between hematopoietic progenitor cells and stromal cells in the bone marrow (BM) and between leukocytes and endothelial as well as dendritic cells. Since VCAM-1-deficient mice die embryonically, conditional VCAM-1 mutant mice were generated to analyze the in vivo function of this adhesion molecule. Here
Ultraviolet radiation can either suppress or induce expression of intercellular adhesion molecule 1 (ICAM-1) on the surface of cultured human keratinocytes
Norris, D.A.; Lyons, M.B.; Middleton, M.H.; Yohn, J.J.; Kashihara-Sawami, M. (Univ. of Colorado Health Sciences Center, Denver (USA))
Interactions of the ligand/receptor pair LFA-1(CD11a/CD18) and ICAM-1(CD54) initiate and control the cell-cell interactions of leukocytes and interactions of leukocytes with parenchymal cells in all phases of the immune response. Induction of the intercellular adhesion molecule 1 (ICAM-1) on the surface of epidermal keratinocytes has been proposed as an important regulator of contact-dependent aspects of cutaneous inflammation. Ultraviolet radiation (UVR) also modifies cutaneous inflammation, producing both up- and down-regulation of contact hypersensitivity. We have found that UVR has a biphasic effect on the induction of keratinocyte CD54. Using immunofluorescence and FACS techniques to quantitate cell-surface CD54 staining, we have shown that UVR significantly (p less than 0.01) inhibits keratinocyte CD54 induction by gamma interferon 24 h after irradiation. However, at 48, 72, and 96 h after UVR, CD54 expression is significantly induced to levels even greater than are induced by gamma interferon (20 U/ml). In addition, at 48, 72, or 96 h following UVR (30-100 mJ/cm2), the gamma-interferon-induced CD54 expression on human keratinocytes is also strongly (p less than 0.05 to p less than 0.001) enhanced. In this cell-culture system, gamma interferon and TNF-alpha are both strong CD54 inducers and are synergistic, but GM-CSF, TFG-beta, and IL-1 have no direct CD54-inducing effects. Thus the effects of UVR on CD54 induction are biphasic, producing inhibition at 24 h and induction at 48, 72, and 96 h. This effect on CD54 may contribute to the biphasic effects of UVR on delayed hypersensitivity in vivo. The early inhibition of ICAM-1 by UVR may also contribute to the therapeutic effects of UVR. We also speculate that the late induction of ICAM-1 by UVR might be an important step in the induction of photosensitive diseases such as lupus erythematosus.
?M?2-integrin-intercellular adhesion molecule-1 interactions drive the flow-dependent trafficking of Guillain-Barrķ syndrome patient derived mononuclear leukocytes at the blood-nerve barrier in vitro
Yosef, Nejla; Ubogu, Eroboghene E.
The mechanisms of hematogenous leukocyte trafficking at the human blood-nerve barrier (BNB) are largely unknown. Intercellular adhesion molecule-1 (ICAM-1) has been implicated in the pathogenesis of Guillain-Barrķ syndrome (GBS). We developed a cytokine-activated human in vitro BNB model using primary endoneurial endothelial cells. Endothelial treatment with 10 U/mL tissue necrosis factor-? and 20 U/mL interferon-? resulted in de novo expression of proinflammatory chemokines CCL2, CXCL9, CXCL11 and CCL20, with increased expression of CXCL2-3, CXCL8 and CXCL10 relative to basal levels. Cytokine treatment induced/ enhanced ICAM-1, E- and P-selectin, vascular cell adhesion molecule-1 and the alternatively spliced pro-adhesive fibronectin variant, fibronectin connecting segment-1 expression in a time-dependent manner, without alterations in junctional adhesion molecule-A expression. Lymphocytes and monocytes from untreated GBS patients express ICAM-1 counterligands, ?M- and ?L-integrin, with differential regulation of ?M-integrin expression compared to healthy controls. Under flow conditions that mimic capillary hemodynamics in vivo, there was a >3-fold increase in total GBS patient and healthy control mononuclear leukocyte adhesion/ migration at the BNB following cytokine treatment relative to the untreated state. Function neutralizing monoclonal antibodies against human ?M-integrin (CD11b) and ICAM-1 reduced untreated GBS patient mononuclear leukocyte trafficking at the BNB by 59% and 64.2% respectively. Monoclonal antibodies against ?L-integrin (CD11a) and human intravenous immunoglobulin reduced total leukocyte adhesion/migration by 22.8% and 17.6% respectively. This study demonstrates differential regulation of ?M-integrin on circulating mononuclear cells in GBS, as well as an important role for ?M-integrin-ICAM-1 interactions in pathogenic GBS patient leukocyte trafficking at the human BNB in vitro. PMID:22552879
Neonatally Induced Inactivation of the Vascular Cell Adhesion Molecule 1 Gene Impairs B Cell Localization and T Cell¢Dependent Humoral Immune Response
Leuker, Christoph E.; Labow, Mark; M³ller, Werner; Wagner, Norbert
Vascular cellular adhesion molecule (VCAM)-1 is a membrane-bound cellular adhesion molecule that mediates adhesive interactions between hematopoietic progenitor cells and stromal cells in the bone marrow (BM) and between leukocytes and endothelial as well as dendritic cells. Since VCAM-1¢deficient mice die embryonically, conditional VCAM-1 mutant mice were generated to analyze the in vivo function of this adhesion molecule. Here we show that interferon-induced Cre-loxP¢mediated deletion of the VCAM-1 gene after birth efficiently ablates expression of VCAM-1 in most tissues like, for example, BM, lymphoid organs, and lung, but not in brain. Induced VCAM-1 deficiency leads to a reduction of immature B cells in the BM and to an increase of these cells in peripheral blood but not in lymphoid organs. Mature recirculating B cells are reduced in the BM. In a migration assay, the number of mature B cells that appears in the BM after intravenous injection is decreased. In addition, the humoral immune response to a T cell¢dependent antigen is impaired. VCAM-1 serves an important role for B cell localization and the T cell¢dependent humoral immune response. PMID:11257141
Expression of glycophosphatidylinositol-anchored and -non-anchored isoforms of vascular cell adhesion molecule 1 in murine stromal and endothelial cells
Tatsuo Kinashi; Timothy A. Springer
Monoclonal antibodies to murine vascular cell adhesion molecule-i (VCAM-1, CD1O6) revealed not only the expected VCAM-1 molecule with an apparent molecular weight of 100 kDa, but also a molecule with a smaller size of 46 kDa in stromal cells and stimulated endothelial cells. Peptide mapping suggested the 46 kDa and 100 kDa proteins were closely related. The 46 kDa, but
Mediation by NF-?B of cytokine induced expression of intercellular adhesion molecule 1 (ICAM-1) in an intestinal epithelial cell line, a process blocked by proteasome inhibitors
C Jobin; C Hellerbrand; L L Licato; D A Brenner; R B Sartor
Background\\/aimsŚThe gene promoter for the intercellular adhesion molecule ICAM-1 possesses binding sites for several transcriptional factors, including nuclear factor ?B (NF-?B). The role of NF-?B in ICAM-1 gene regulation was therefore examined by using different proteasome inhibitors in tumour necrosis factor ? (TNF-?) stimulated IEC-6 rat intestinal epithelial cells.MethodsŚICAM-1 expression was analysed by enzyme linked immunosorbent assay (ELISA), reverse transcriptase
Epstein¢Barr Virus Latent Membrane Protein1 Induction by Histone Deacetylase Inhibitors Mediates Induction of Intercellular Adhesion Molecule1 Expression and Homotypic Aggregation
Jae Hong Park; Douglas V. Faller
Epstein¢Barr virus (EBV) latent membrane protein (LMP)-1 induces B lymphocyte immortalization and activates constitutive signal transduction, including NF-?B, JNK\\/p38, and JAK\\/STAT pathways. During EBV latency, LMP-1 expression induces several B lymphocyte activation markers, including intercellular adhesion molecule (ICAM)-1. We found that various structurally distinct histone deacetylase inhibitors (HDACI), as well as phorbol ester treatment, induced homotypic aggregation in EBV-positive Burkitt's
High insulin enhances neutrophil transendothelial migration through increasing surface expression of platelet endothelial cell adhesion molecule-1 via activation of mitogen activated protein kinase
M. Okouchi; N. Okayama; S. Imai; H. Omi; M. Shimizu; T. Fukutomi; M. Itoh
ĀĀAbstract\\u000a \\u000a \\u000a Aims\\/hypothesis. There is increasing evidence that hyperinsulinaemia is linked with the development of atherosclerosis in patients with diabetes.\\u000a However, the mechanisms by which hyperinsulinaemia causes accelerated atherosclerosis, especially with respect to leukocytes\\u000a transendothelial migration, are poorly understood. We examined whether hyperinsulinaemia directly affects neutrophil transendothelial\\u000a migration and surface expression of related endothelial adhesion molecules.\\u000a \\u000a \\u000a \\u000a \\u000a Methods. Experiments on the transmigration
Chemoattractants Induce a Rapid and Transient Upregulation of Monocyte ?4 Integrin Affinity for Vascular Cell Adhesion Molecule 1 Which Mediates Arrest
Chan, Jason R.; Hyduk, Sharon J.; Cybulsky, Myron I.
Chemoattractants and chemokines induce arrest of rolling monocytes during emigration from blood into tissues. In this study, we demonstrated that ?4 integrin affinity for vascular cell adhesion molecule (VCAM)-1 was upregulated rapidly and transiently by chemoattractants and stromal cell¢derived factor (SDF)-1? and mediated monocyte arrest. ?4 integrin affinity changes were detected and blocked using soluble VCAM-1/Fc (sVCAM-1/Fc). In a flow cytometry assay, markedly increased sVCAM-1/Fc binding to human blood monocytes or U937 cells transfected with formyl peptide (FP) receptor was detected 30 s after FP or SDF-1? treatment and declined after 2 min. In a parallel plate flow chamber assay, FP, C5a, platelet-activating factor, or SDF-1? coimmobilized with VCAM-1 induced leukocyte arrest, which was blocked by inclusion of sVCAM-1/Fc but not soluble nonimmune immunoglobulin G in the assay buffer. PMID:11369786
Reduced expression of adipose triglyceride lipase enhances tumor necrosis factor alpha-induced intercellular adhesion molecule-1 expression in human aortic endothelial cells via protein kinase C-dependent activation of nuclear factor-kappaB.
Inoue, Tomoaki; Kobayashi, Kunihisa; Inoguchi, Toyoshi; Sonoda, Noriyuki; Fujii, Masakazu; Maeda, Yasutaka; Fujimura, Yoshinori; Miura, Daisuke; Hirano, Ken-Ichi; Takayanagi, Ryoichi
We examined the effects of adipose triglyceride lipase (ATGL) on the initiation of atherosclerosis. ATGL was recently identified as a rate-limiting triglyceride (TG) lipase. Mutations in the human ATGL gene are associated with neutral lipid storage disease with myopathy, a rare genetic disease characterized by excessive accumulation of TG in multiple tissues. The cardiac phenotype, known as triglyceride deposit cardiomyovasculopathy, shows massive TG accumulation in both coronary atherosclerotic lesions and the myocardium. Recent reports show that myocardial triglyceride content is significantly higher in patients with prediabetes or diabetes and that ATGL expression is decreased in the obese insulin-resistant state. Therefore, we investigated the effect of decreased ATGL activity on the development of atherosclerosis using human aortic endothelial cells. We found that ATGL knockdown enhanced monocyte adhesion via increased expression of TNF?-induced intercellular adhesion molecule-1 (ICAM-1). Next, we determined the pathways (MAPK, PKC, or NF?B) involved in ICAM-1 up-regulation induced by ATGL knockdown. Both phosphorylation of PKC and degradation of I?B? were increased in ATGL knockdown human aortic endothelial cells. In addition, intracellular diacylglycerol levels and free fatty acid uptake via CD36 were significantly increased in these cells. Inhibition of the PKC pathway using calphostin C and GF109203X suppressed TNF?-induced ICAM-1 expression. In conclusion, we showed that ATGL knockdown increased monocyte adhesion to the endothelium through enhanced TNF?-induced ICAM-1 expression via activation of NF?B and PKC. These results suggest that reduced ATGL expression may influence the atherogenic process in neutral lipid storage diseases and in the insulin-resistant state. PMID:21828047
Mononuclear Cell Recruitment, Granuloma Assembly, and Response to Treatment in Experimental Visceral Leishmaniasis: Intracellular Adhesion Molecule 1-Dependent and -Independent Regulation
Murray, Henry W.
In experimental visceral leishmaniasis, acquired resistance to intracellular Leishmania donovani is Th1 cell cytokine dependent and largely mediated by gamma interferon (IFN-?); the same response also permits conventional antimony (Sb) chemotherapy to express its leishmanicidal effect. Since the influxing blood monocyte (which utilizes endothelial cell ICAM-1 for adhesion and tissue entry) is a primary effector target cell for this cytokine mechanism, we tested the monocyte's role in host responsiveness to chemotherapy in mice with ICAM-1 gene disruptions. Mutant animals failed to develop any early granulomatous tissue response in the liver, initially supported high-level visceral parasite replication, and showed no killing after Sb treatment; the leishmanicidal response to a directly acting, alternative chemotherapeutic probe, amphotericin B, was intact. However, mutant mice proceeded to express a compensatory, ICAM-1-independent response leading to mononuclear cell influx and granuloma assembly, control over visceral infection, and the capacity to respond to Sb. Together, these results point to the recruitment of emigrant monocytes and mononuclear cell granuloma formation, mediated by ICAM-1-dependent and -independent pathways, as critical determinants of host responsiveness to conventional antileishmanial chemotherapy. PMID:11035738
Ursolic acid, a natural pentacyclic triterpenoid, inhibits intracellular trafficking of proteins and induces accumulation of intercellular adhesion molecule-1 linked to high-mannose-type glycans in the endoplasmic reticulum
Mitsuda, Satoshi; Yokomichi, Tomonobu; Yokoigawa, Junpei; Kataoka, Takao
Ursolic acid (3?-hydroxy-urs-12-en-28-oic acid) is a natural pentacyclic triterpenoid that is present in many plants, including medicinal herbs, and foods. Ursolic acid was initially identified as an inhibitor of the expression of intercellular adhesion molecule-1 (ICAM-1) in response to interleukin-1? (IL-1?). We report here a novel biological activity: ursolic acid inhibits intracellular trafficking of proteins. Ursolic acid markedly inhibited the IL-1?-induced cell-surface ICAM-1 expression in human cancer cell lines and human umbilical vein endothelial cells. By contrast, ursolic acid exerted weak inhibitory effects on the IL-1?-induced ICAM-1 expression at the protein level. Surprisingly, we found that ursolic acid decreased the apparent molecular weight of ICAM-1 and altered the structures of N-linked oligosaccharides bound to ICAM-1. Ursolic acid induced the accumulation of ICAM-1 in the endoplasmic reticulum, which was linked mainly to high-mannose-type glycans. Moreover, in ursolic-acid-treated cells, the Golgi apparatus was fragmented into pieces and distributed over the cells. Thus, our results reveal that ursolic acid inhibits intracellular trafficking of proteins and induces the accumulation of ICAM-1 linked to high-mannose-type glycans in the endoplasmic reticulum. PMID:24649404
Luteolin protects against vascular inflammation in mice and TNF-alpha-induced monocyte adhesion to endothelial cells via suppressing I?B?/NF-?B signaling pathway.
Jia, Zhenquan; Nallasamy, Palanisamy; Liu, Dongmin; Shah, Halley; Li, Jason Z; Chitrakar, Rojin; Si, Hongwei; McCormick, John; Zhu, Hong; Zhen, Wei; Li, Yunbo
Vascular inflammation plays a significant role in the pathogenesis of atherosclerosis. Luteolin, a naturally occurring flavonoid present in many medicinal plants and some commonly consumed fruits and vegetables, has received wide attention for its potential to improve vascular function in vitro. However, its effect in vivo and the molecular mechanism of luteolin at physiological concentrations remain unclear. Here, we report that luteolin as low as 0.5 ?M significantly inhibited tumor necrosis factor (TNF)-?-induced adhesion of monocytes to human EA.hy 926 endothelial cells, a key event in triggering vascular inflammation. Luteolin potently suppressed TNF-?-induced expression of the chemokine monocyte chemotactic protein-1 (MCP-1) and adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), key mediators involved in enhancing endothelial cell-monocyte interaction. Furthermore, luteolin inhibited TNF-?-induced nuclear factor (NF)-?B transcriptional activity, I?B? degradation, expression of I?B kinase ? and subsequent NF-?B p65 nuclear translocation in endothelial cells, suggesting that luteolin can inhibit inflammation by suppressing NF-?B signaling. In an animal study, C57BL/6 mice were fed a diet containing 0% or 0.6% luteolin for 3 weeks, and luteolin supplementation greatly suppressed TNF-?-induced increase in circulating levels of MCP-1/JE, CXCL1/KC and sICAM-1 in C57BL/6 mice. Consistently, dietary intake of luteolin significantly reduced TNF-?-stimulated adhesion of monocytes to aortic endothelial cells ex vivo. Histology shows that luteolin treatment prevented the eruption of endothelial lining in the intima layer of the aorta and preserved elastin fibers' delicate organization as shown by Verhoeff-Van Gieson staining. Immunohistochemistry studies further show that luteolin treatment also reduced VCAM-1 and monocyte-derived F4/80-positive macrophages in the aorta of TNF-?-treated mice. In conclusion, luteolin protects against TNF-?-induced vascular inflammation in both in vitro and in vivo models. This anti-inflammatory effect of luteolin may be mediated via inhibition of the NF-?B-mediated pathway. PMID:25577468
Crystal structure of the V domain of human Nectin-like molecule-1/Syncam3/Tsll1/Igsf4b, a neural tissue-specific immunoglobulin-like cell-cell adhesion molecule.
Dong, Xiuhua; Xu, Feng; Gong, Yanhua; Gao, Jing; Lin, Peng; Chen, Tao; Peng, Ying; Qiang, Boqin; Yuan, Jiangang; Peng, Xiaozhong; Rao, Zihe
Nectins are Ca(2+)-independent immunoglobulin (Ig) superfamily proteins that participate in the organization of epithelial and endothelial junctions. Nectins have three Ig-like domains in the extracellular region, and the first one is essential in cell-cell adhesion and plays a central role in the interaction with the envelope glycoprotein D of several viruses. Five Nectin-like molecules (Necl-1 through -5) with similar domain structures to those of Nectins have been identified. Necl-1 is specifically expressed in neural tissue, has Ca(2+)-independent homophilic and heterophilic cell-cell adhesion activity, and plays an important role in the formation of synapses, axon bundles, and myelinated axons. Here we report the first crystal structure of its N-terminal Ig-like V domain at 2.4 A, providing insight into trans-cellular recognition mediated by Necl-1. The protein crystallized as a dimer, and the dimeric form was confirmed by size-exclusion chromatography and chemical cross-linking experiments, indicating this V domain is sufficient for homophilic interaction. Mutagenesis work demonstrated that Phe(82) is a key residue for the adhesion activity of Necl-1. A model for homophilic adhesion of Necl-1 at synapses is proposed based on its structure and previous studies. PMID:16467305
Intercellular adhesion molecules (ICAMs) and spermatogenesis
Xiao, Xiang; Mruk, Dolores D.; Cheng, C. Yan
BACKGROUND During the seminiferous epithelial cycle, restructuring takes places at the Sertoli¢Sertoli and Sertoli¢germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move æup and downÆ the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood¢testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)ŚBTBŚbasement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. METHODS Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. RESULTS Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. CONCLUSIONS ICAMs are crucial regulatory molecules of spermatogenesis. The proposed hypothetical model serves as a framework in designing functional experiments for future studies. PMID:23287428
Brucella abortus as a potential vaccine candidate: induction of interleukin-12 secretion and enhanced B7.1 and B7.2 and intercellular adhesion molecule 1 surface expression in elutriated human monocytes stimulated by heat-inactivated B. abortus.
Zaitseva, M; Golding, H; Manischewitz, J; Webb, D; Golding, B
Development of a vaccine which is capable of generating a strong cellular immune response associated with gamma interferon (IFN-gamma) production and cytotoxic T-cell development requires that the immunogen be capable of inducing the secretion of interleukin-12 (IL-12), which is a pivotal factor for the differentiation of Th1 or Tc1 cells. We have previously shown that the heat-inactivated gram-negative bacterium Brucella abortus can induce IFN-gamma secretion by T cells. In the present study, we demonstrate that B. abortus and lipopolysaccharide (LPS) from B. abortus can induce IL-12 p40 mRNA expression and protein secretion by human elutriated monocytes (99% pure). p40 mRNA was detected within 4 h, and p40 protein could be measured at 24 h. This induction was abrogated by anti-CD14 monoclonal antibody, suggesting that monocytes recognize B. abortus via their receptor for LPS. The biological activity of IL-12 secreted by B. abortus-stimulated monocytes was demonstrated by its ability to upregulate IFN-gamma mRNA expression in T cells separated from monocytes and B. abortus by a transwell membrane. The B. abortus-induced IL-12 also enhanced NK cytolytic activity against K562 target cells. B. abortus was shown to rapidly increase the expression of the costimulatory molecules B7.1 and B7.2 and intercellular adhesion molecule 1 on human monocytes. Together, these data indicate that B. abortus can directly activate human monocytes and provide the cytokine milieu which would direct the immune response towards Th1-Tc1 differentiation. PMID:8757841
Serum Soluble Adhesion Molecules and Markers of Systemic Inflammation in Elderly Diabetic Patients with Mild Cognitive Impairment and Depressive Symptoms
Gorska-Ciebiada, Malgorzata; Saryusz-Wolska, Malgorzata; Borkowska, Anna; Ciebiada, Maciej; Loba, Jerzy
The aim of the study was to determine the serum levels of soluble adhesion molecules and hs-CRP in elderly diabetics with mild cognitive impairment (MCI) alone or with depressive symptoms. Methods. 219 diabetics elders were screened for psychiatric disorders and divided: group 1, MCI without depressive mood; group 2, MCI with depressive mood; group 3, controls. Data of biochemical parameters and biomarkers were collected. Results. In groups 1 and 2 levels of all biomarkers were significantly higher as compared to controls. The highest level of hs-CRP and sICAM-1 was detected in group 2. SVCAM-1 and sE-selectin levels were also the highest in group 2; however they did not significantly differ as compared to group 1. MoCA score was negatively correlated with all biomarkers in group 1. The logistic regression model showed that variables which increased the likelihood of having depressive syndrome in MCI patients were older age, stroke, neuropathy, increased number of comorbidities, and higher sICAM-1 level. Conclusions. We first demonstrated that elderly diabetic patients with MCI, particularly those with depressive mood have higher levels of soluble adhesion molecules and markers of low-grade systemic inflammation. Coexisting depressive syndrome in patients with MCI through common inflammatory pathways may result in augmentation of psychiatric disorders.
Serum inflammatory markers and clinical\\/MRI markers of disease progression in multiple sclerosis
G. Giovannoni; D. H. Miller; N. A. Losseff; M. Sailer; N. Lewellyn-Smith; A. J. Thompson; E. J. Thompson
The aim of this study was to assess whether mean serum levels of inflammatory markers when measured serially correlate with\\u000a disease progression or putative MRI markers of axonal loss in a cohort of well-characterised multiple sclerosis (MS) patients.\\u000a Serial serum levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1),\\u000a nitric oxide metabolites nitrate and nitrite (NOx),
Elevation of serum KL-6 levels in patients with hematological malignancies associated with cytomegalovirus or Pneumocystis carinii pneumonia.
Tanaka, M; Tanaka, K; Fukahori, S; Fujimatsu, Y; Jojima, H; Shiraishi, K; Honda, J; Oizumi, K
The level of serum KL-6 antigen has been reported to be a sensitive indicator of various interstitial pneumonitis, but in patients with hematological malignancies who were accompanied by infective interstitial pneumonitis like Pneumocystis carinii or cytomegalovirus (CMV) pneumonia, it is still unknown whether serum KL-6 level is useful as a good marker for the diagnosis or disease activity. In this study, the serum levels of KL-6 and soluble intercellular adhesion molecule 1 (sICAM-1) were evaluated in five patients with malignant lymphoma or adult T-cell leukemia. Serum KL-6 and sICAM-1 levels at the time of diagnosis of P. carinii or CMV pneumonia were 1220+/-323 U/ml (mean+/-SD) and 1246+/-485 ng/ml, respectively. These levels were apparently high, when compared with standard value of serum KL-6 (<520 U/ml) and that of sICAM-1 (115-306 ng/ml). In patients without P. carinii or CMV pneumonia, who had hematological malignancies or AIDS, serum level of KL-6 was not high (299+/-122 U/ml), but sICAM-1 was high (651+/-495 ng/ml) because of the elevation of sICAM-1 in four of five cases. These findings suggest that, in patients with hematological malignancies, serum level of KL-6 antigen rather than sICAM-1 may be useful in the evaluation of CMV or P. carinii pneumonia. PMID:12186700
Primary Structure of the Leukocyte Function-associated Molecule1 Subunit: an Integrin with an Embedded Domain Defining a Protein Superfamily
Richard S. Larson; Angel L. Corbi; Lisa Berman; Timothy Springer
The leukocyte function-associated molecule 1 (LFA-1, CDlla\\/CD18) is a membrane glycoprotein which functions in cell-cell adhesion by heterophilic interaction with intercellular adhesion molecule 1 (ICAM-1). LFA-1 consists of an ot subunit (Mr = 180,000) and a ~ subunit (Mr = 95,000). We report the molecular biology and protein sequence of the a subunit. Overlapping cDNAs containing 5,139 nucleo- tides were
Intercellular adhesion molecule-1 is an endothelial cell adhesion receptor for Plasmodium falciparum
A. R. Berendt; D. L. Simmons; J. Tansey; C. I. Newbold; K. Marsh
THE primary event in the pathogenesis of severe malaria in Plasmodium falciparum infection is thought fo be adherence of trophozoite- and schizont-infected erythrocytes to capillary endothelium1, a process called sequestration. Identifying the endothelial molecules used as receptors is an essential step in understanding this disease process. Recent work implicates the membrane glycoprotein CD36 (platelet glycoprotein IV; refs 2-5) and the
Smoke and C5a Induce Airway Epithelial Intercellular Adhesion Molecule1 and Cell Adhesion
Anthony A. Floreani; Todd A. Wyatt; Julie Stoner; Sam D. Sanderson; Ethan G. Thompson; Diane Allen-Gipson; Art J. Heires
The human bronchial epithelial cell is one of the first cell types to be exposed to the irritants and toxins present in inhaled cigarette smoke. The ability of the bronchial epithelium to mod- ulate inflammatory and immune events in response to cigarette smoke is important in the pathogenesis of smoke-induced air- way injury. We have shown that cigarette smoke extract
Visual prognosis and vitreous molecules after vitrectomy for macular edema with branch retinal vein occlusion
Noma, Hidetaka; Funatsu, Hideharu; Mimura, Tatsuya; Eguchi, Shuichiro; Shimada, Katsunori
This study investigated whether vascular endothelial growth factor (VEGF), soluble intercellular adhesion molecule-1 (sICAM-1), and pigment epithelium-derived factor (PEDF) influence the visual prognosis of patients with macular edema and branch retinal vein occlusion (BRVO). In 47 consecutive patients (47 eyes) undergoing vitrectomy, retinal thickness was examined by optical coherence tomography. Best-corrected visual acuity and the vitreous fluid levels of VEGF, sICAM-1, and PEDF were also determined. Patients were followed for at least 6 months after surgery. Vitreous fluid levels of VEGF and sICAM-1 were significantly lower in the patients with more marked improvement of visual acuity after vitrectomy, while PEDF was significantly higher. VEGF and sICAM-1 levels were significantly higher in patients with greater postoperative improvement of macular edema, while PEDF was significantly lower. In BRVO patients, vitreous fluid levels of VEGF, sICAM-1, and PEDF may influence both the response of macular edema to vitrectomy and the visual prognosis. PMID:21386915
Effect of ozone and nitrogen dioxide on the release of proinflammatory mediators from bronchial epithelial cells of nonatopic nonasthmatic subjects and atopic asthmatic patients in vitro
Hasan Bayram; Raymond J. Sapsford; Muntasir M. Abdelaziz; Omar A. Khair
Background: Although studies have suggested that ozone (O3) and nitrogen dioxide (NO2) may play a role in the pathogenesis of asthma, the underlying mechanisms are not clear. Objective: We aimed to investigate the effects of O3 and NO2 on the release of IL-8, GM-CSF, RANTES, and soluble intercellular adhesion molecule 1 (sICAM-1) from human bronchial epithelial cells (HBECs) of nonatopic
Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight men.
Esser, Diederik; Mars, Monica; Oosterink, Els; Stalmach, Angelique; M³ller, Michael; Afman, Lydia A
Flavanol-enriched chocolate consumption increases endothelium-dependent vasodilation. Most research so far has focused on flow-mediated dilation (FMD) only; the effects on other factors relevant to endothelial health, such as inflammation and leukocyte adhesion, have hardly been addressed. We investigated whether consumption of regular dark chocolate also affects other markers of endothelial health, and whether chocolate enrichment with flavanols has additional benefits. In a randomized double-blind crossover study, the effects of acute and of 4 wk daily consumption of high flavanol chocolate (HFC) and normal flavanol chocolate (NFC) on FMD, augmentation index (AIX), leukocyte count, plasma cytokines, and leukocyte cell surface molecules in overweight men (age 45-70 yr) were investigated. Sensory profiles and motivation scores to eat chocolate were also collected. Findings showed that a 4 wk chocolate intake increased FMD by 1%, which was paralleled by a decreased AIX of 1%, decreased leukocyte cell count, decreased plasma sICAM1 and sICAM3, and decreased leukocyte adhesion marker expression (P<0.05 for time effect), with no difference between HFC and NFC consumption. Flavanol enrichment did affect taste and negatively affected motivation to consume chocolate. This study provides new insights on how chocolate affects endothelial health by demonstrating that chocolate consumption, besides improving vascular function, also lowers the adherence capacity of leukocytes in the circulation. PMID:24302679
Circulating adhesion molecules after short-term exposure to particulate matter among welders
Fang, S C; Eisen, E A; Cavallari, J M; Mittleman, M A; Christiani, D C
Background Studies from several countries indicate that welders experience increased risk of mortality and morbidity from ischaemic heart disease. Although the underlying mechanisms are unclear, vascular responses to particulate matter contained in welding fumes may play a role. To investigate this, we studied the acute effects of welding fume exposure on the endothelial component of vascular function, as measured by circulating adhesion molecules involved in leukocyte adhesion (sICAM-1 and sVCAM-1) and coagulation (vWF). Methods A panel of 26 male welders was studied repeatedly across a 6 h work-shift on a high exposure welding day and/or a low exposure non-welding day. Personal PM2.5 exposure was measured throughout the work-shift. Blood samples were collected in the morning (baseline) prior to the exposure period, immediately after the exposure period, and the following morning. To account for the repeated measurements, we used linear mixed models to evaluate the effects of welding (binary) and PM2.5 (continuous) exposure on each blood marker, adjusting for baseline blood marker concentration, smoking, age and time of day. Results Welding and PM2.5 exposure were significantly associated with a decrease in sVCAM-1 in the afternoon and the following morning and an increase in vWF in the afternoon. Conclusions The data suggest that welding and short-term occupational exposure to PM2.5 may acutely affect the endothelial component of vascular function. PMID:19736177
Brian Savage; Zaverio M. Ruggeri
Platelet adhesion and ensuing thrombus formation play a central role in normal hemostasis as well as in the pathogenesis of\\u000a acute coronary syndromes and thrombotic disorders. Circulating blood platelets adhere to sites of vascular injury through\\u000a specific adhesion receptors despite the hemodynamic forces in flowing blood that oppose adhesion contacts. At high shear,\\u000a this process is initiated by the reversible
Tasto, James P; Elias, David W
Adhesive capsulitis is a common problem seen in the general population by orthopedic surgeons. It is a problem that causes patients pain and disability, and symptoms can last up to 2 years and longer. The questions of when and how to treat the frozen shoulder can present challenges. Most treatments are conservative; however, indications for surgery do exist. Arthroscopic capsular release has gained popularity over the years and offers a predictably good treatment in patients with adhesive capsulitis. The purpose of this paper is to review the orthopedic literature on adhesive capsulitis, to provide background information on this topic, and to describe our technique in arthroscopic capsular release. PMID:18004221
... abdominal tissues and organs. [ Top ] What is the abdominal cavity? The abdominal cavity is the internal area of the body between ... develop abdominal adhesions. 1 Surgery in the lower abdomen and pelvis, including bowel and gynecological operations, carries ...
Relationship between serum estrogen levels and blood stasis syndrome in postmenopausal women with coronary heart disease
Liu, Xin; Guo, Chunyu; Ma, Xiaojuan; Tian, Rui; Zhang, Ying; Yin, Huijun
Objectives: To investigate the difference of serum estrogen, serum lipids and inflammatory factors levels in postmenopausal women with coronary heart blood stasis syndrome and non-blood stasis syndrome. Methods: Twenty five healthy postmenopausal women were selected as a healthy control group who were compared with 43 postmenopausal women with coronary heart disease (CHD) first visiting a doctor for the CHD. Among the postmenopausal women with CHD, There were 23 patients with blood stasis syndrome (BSS) and 20 patients with non-blood stasis syndrome (NBSS). The levels of plasma triglyceride (TG), total cholesterol (TC) were determined in blood samples taken after patientsÆ admission in Beijing Anzhen Hospital. The serum estradiol(E2) was measured by electrochemiluminescence assay and soluble intercellular adhesion molecule-1(sICAM-1) was measured by enzyme-linked immune sorbent assay (ELISA). Results: Compared with the healthy control group, the levels of TG and TC, sICAM-1 in coronary heart disease group were all significantly increased (P<0.05),but serum E2 were significantly decreased (P<0.05). The levels of E2 of patients with blood stasis syndrome (BSS) were decreased further (P>0.05), and there was an increasing trend of serum sICAM-1 levels (P>0.05). There were negative significant correlations between serum E2 levels and TC, sICAM-1 levels in patient with coronary heart disease. Conclusion: The estrogen level of menopausal women with coronary heart disease is lower than healthy menopausal women. With the low estrogen levels, postmenopausal women tend to have high levels of blood lipids and sICAM-1, which elucidates that the estrogen could regulate lipids and attenuate inflammatory response to play a protective role on blood vessels. PMID:25878609
The Associrlation of the Seaum Cellular Adhesion Molecule Level with Tytepe One Diabetes Aetinotathy
HAN Mei
Objective Tobetter understand potential associations of circulating adhesionmolecules(cAMs) with diabetic retinopathy(DR) ,circu2 lation serum concentrations of intercellular adhesion molecule - 1 ( cICAM - 1) was determined in patients with insulin - dependent diabetic mellitus ( IDDM n = 32) presenting with varying degrees of metabolic control and status of diabetic retinopathy. Methods The serum levels of circulative intercellular adhesion
Evidence of Endothelial Activation in Asymptomatic Plasmodium falciparum Parasitemia and Effect of Blood Group on Levels of von Willebrand Factor in Malaria
Park, Gregory S.; Ireland, Kathleen F.; Opoka, Robert O.; John, Chandy C.
Background. Endothelial activation may contribute to development of severe disease from Plasmodium falciparum infection, but optimal markers of endothelial activation in severe malaria, the extent of endothelial activation in asymptomatic infection, and the effect of blood group O on endothelial activation have not been defined. Methods. Serum levels of 3 markers of endothelial activationŚvon Willebrand factor (VWF), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1)Śwere assessed in Ugandan children with cerebral malaria (CM) (nĀ=Ā86), children with uncomplicated malaria (UM) (nĀ=Ā81), and community children (CC) (nĀ=Ā90). Results. Serum VWF, sICAM-1, and sVCAM-1 levels were all elevated in asymptomatic community children with microscopy-confirmed parasitemia when compared with children without parasitemia by microscopy or polymerase chain reaction (all, PĀ?Ā.05). Levels of VWF, sICAM-1, and sVCAM-1 were higher in children with UM than in CC (all, PĀ<Ā0.001), but only VWF levels effectively distinguished CM from UM (PĀ<Ā0.001), a finding confirmed by receiver operating characteristic analyses (area under the curveĀ=Ā0.67; 95% confidence interval, .58¢.75). Von Willebrand factor levels were lower in children with blood group O versus non-O blood groups across the disease spectrum, but VWF levels remained higher in CM versus UM, even after controlling for blood group. Conclusions. Endothelial activation, as assessed by serum levels of VWF, sICAM-1, and sVCAM-1, occurs even in subclinical P. falciparum parasitemia. Von Willebrand factor levels increase with greater malaria disease severity. Blood group O is associated with lower VWF levels, but presence of blood group O alone does not explain the higher VWF levels seen in children with CM. PMID:23687570
NASA Technical Reports Server (NTRS)
Progar, D. J.; Bell, V. L.; Saintclair, T. L. (inventors)
A process of preparing aromatic polyamide-acids for use as adhesives is described. An equimolar quantity of an aromatic dianhydride is added to a stirred solution of an aromatic diamine in a water or alcohol-miscible ether solvent to obtain a viscous polymer solution. The polymeric-acid intermediate polymer does not become insoluble but directly forms a smooth viscous polymer solution. These polyamic-acid polymers are converted, by heating in the range of 200-300 C and with pressure, to form polyimides with excellent adhesive properties.
Dong, Cheng
molecule-1 (ICAM-1) was found on C8161 cells. In contrast, levels of 2-integrins (e.g., LFA-1 and Mac- 1 for prolonged shear-resis- tant attachment, is mediated by 2-integrins (Mac-1 or LFA-1) expressed sug- gested that LFA-1 to ICAM-1 adhesion is important in initial endothelial capture of PMNs, while
Expression of leucocyte and lymphocyte adhesion molecules in the human kidney
G Alex Bishop; Bruce M Hall
Expression of leucocyte and lymphocyte adhesion molecules in the human kidney. Leucocyte interaction with other cells is facilitated by the adhesion molecules, leucocyte function-associated antigen-1 (LFA-l)-binding to intercellular adhesion molecule-1 (ICAM-1) and for T cells and natural killer (NK) cells the binding of LFA-2 (CD2) to LFA-3. As these interactions are critical for the mediation of graft destruction by effector
Effect of Platelet-Activating Factor and Platelet Factor 4 on Eosinophil Adhesion
Nobana Hayashi; Junichi Chihara; Yohnosuke Kobayashi; Tomokazu Kakazu; Dai Kurachi; Takahiro Yamamoto; Shigenori Nakajima
The effect of platelet-activating factor (PAF) and platelet factor 4 (PF4) on the adhesion of isolated human eosinophils or eosinophilic cell lines (EoL-1, EoL-3) was examined. Both PAF and PF4 augmented eosinophil adhesion to plates coated with AB plasma or recombinant soluble intercellular adhesion molecule-1 (r-sICAM-1). These findings suggest that PAF and PF4 not only modulate chemotactic activity of eosinophils
Some fundamentals of adhesion in synthetic adhesives
Cyprien Gay
Various adhesion mechanisms that have been understood in the field of synthetic adhesives are described and these are linked with situations relevant to fouling issues. The review mainly deals with mechanical aspects of adhesion phenomena, with an emphasis on the role of the elasticity of the bodies, called substrata, attached by adhesive. The consequences of thin film geometry of the
Adhesive Properties of Model, Filled Elastomeric Adhesives
Peter Drzal; Elizabeth Cheang; Kenneth Shull
Adhesive properties of a model, filled elastomeric adhesive are measured using an axisymmetic adhesion test with a rigid glass indenter. Experiments with poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) triblock copolymer films are conducted with two types of complementary experiments to resolve the surface and bulk contribution to the adhesive behavior. In the first set of experiments, thermally evaporated gold particles are deposited
Nanofibrous adhesion: the twin of gecko adhesion.
Gong, Guangming; Zhou, Chen; Wu, Juntao; Jin, Xu; Jiang, Lei
Inspired by dusty spider dragline silk, we studied the adhesive interaction between artificial nanofibers and their aerosol surroundings. The nanofibers are found to be able to actively capture particulate matters from the environment, exactly as the spider dragline silk does. Examinations prove that such nanofibrous adhesion is insensitive to the chemical nature of the fibers and the physical states of the particulate matter and depends only on the fiber diameters. Such facts indicate that nanofibrous adhesion is a case of dry adhesion, mainly governed by van der Waals force, sharing the same mechanism to gecko adhesion. Nanofibrous adhesion is of great importance and has promising potential. For instance, in this work, nanofibers are fabricated into a thin and translucent filter, which has a filtration performance, as high as 95%, that easily outperformed ordinary ones. We believe that this adhesive property of nanofibers will open up broader applications in both scientific and industrial fields. PMID:25602975
Iron sucrose accelerates early atherogenesis by increasing superoxide production and upregulating adhesion molecules in CKD.
Kuo, Ko-Lin; Hung, Szu-Chun; Lee, Tzong-Shyuan; Tarng, Der-Cherng
High-dose intravenous iron supplementation is associated with adverse cardiovascular outcomes in patients with CKD, but the underlying mechanism is unknown. Our study investigated the causative role of iron sucrose in leukocyte-endothelium interactions, an index of early atherogenesis, and subsequent atherosclerosis in the mouse remnant kidney model. We found that expression levels of intracellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and adhesion of U937 cells increased in iron-treated human aortic endothelial cells through upregulated NADPH oxidase (NOx) and NF-?B signaling. We then measured mononuclear-endothelial adhesion and atherosclerotic lesions of the proximal aorta in male C57BL/6 mice with subtotal nephrectomy, male apolipoprotein E-deficient (ApoE(-/-)) mice with uninephrectomy, and sham-operated mice subjected to saline or parenteral iron loading. Iron sucrose significantly increased tissue superoxide production, expression of tissue cell adhesion molecules, and endothelial adhesiveness in mice with subtotal nephrectomy. Moreover, iron sucrose exacerbated atherosclerosis in the aorta of ApoE(-/-) mice with uninephrectomy. In patients with CKD, intravenous iron sucrose increased circulating mononuclear superoxide production, expression of soluble adhesion molecules, and mononuclear-endothelial adhesion compared with healthy subjects or untreated patients. In summary, iron sucrose aggravated endothelial dysfunction through NOx/NF-?B/CAM signaling, increased mononuclear-endothelial adhesion, and exacerbated atherosclerosis in mice with remnant kidneys. These results suggest a novel causative role for therapeutic iron in cardiovascular complications in patients with CKD. PMID:24722448
Adhesive Properties of Model, Filled Elastomeric Adhesives
NASA Astrophysics Data System (ADS)
Drzal, Peter; Cheang, Elizabeth; Shull, Kenneth
Adhesive properties of a model, filled elastomeric adhesive are measured using an axisymmetic adhesion test with a rigid glass indenter. Experiments with poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) triblock copolymer films are conducted with two types of complementary experiments to resolve the surface and bulk contribution to the adhesive behavior. In the first set of experiments, thermally evaporated gold particles are deposited onto the triblock copolymer to yield gold coatings with equivalent thicknesses of 100 nm or less. The axisymmetric adhesion test is used to measure the force required to separate the glass indenter from the gold coated triblock copolymer substrates. The work of adhesion decreases with increasing thickness of the gold coating. This result is attributed to a reduction in the true area of contact between the indenter and the adhesive upon the addition of the metal particle layer. In the second set of experiments, effects of rigid particles on the bulk mechanical properties and adhesive response are probed by adding spherical aluminum oxide particles to the adhesive. In both sets of experiments, approaches based on linear elastic fracture mechanics are used to quantify the adhesive response.
Periatrial Epicardial Fat Is Associated with Markers of Endothelial Dysfunction in Patients with Atrial Fibrillation
Girerd, Nicolas; Scridon, Alina; BessiĶre, Francis; Chauveau, Samuel; Geloen, Alain; Boussel, Loic; Morel, Elodie; Chevalier, Philippe
Background Epicardial adipose tissue (EAT) is associated to atrial fibrillation (AF) burden and outcome after AF ablation. We intended to determine whether global or local EAT is associated with systemic and/or left atrial (LA) inflammation and markers of endothelial dysfunction in AF patients. Methods and Results Total, atrial, and ventricular EAT volume (EATtotal, EATatrial, EATventricular) were measured by multislice cardiac CT in 49 patients with paroxysmal (PAF, n=25) or persistent AF (PeF, n=24). Periatrial epicardial fat thickness at the esophagus (LA-ESO) and thoracic aorta (LA-ThA) were also measured. Vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), soluble intercellular adhesion molecule 1 (sICAM-1), transforming growth factor-?1 (TGF-?1), and von Willebrand Factor (vWF) levels were measured in peripheral and LA blood samples obtained during catheterization during AF ablation. Patients with PeF had higher EATatrial (P<0.05) and LA-ESO (P=0.04) than patients with PAF. VEGF, IL-8, and TGF-?1 were not associated with EAT. In contrast, after adjusting for LA volume and body mass index, higher LA-ThA was significantly associated with higher sICAM-1 and vWF levels, both in peripheral blood (P<0.05) and in LA (P<0.05). Similar results were found with LA-ESO. Body mass index, EATtotal and EATventricular were not associated with sICAM-1 and vWF. Conclusions Periatrial epicardial fat showed a significant positive association with increased levels of sICAM-1 and vWF, which are biomarkers of endothelial dysfunction. No such associations were found when considering body mass index or EATtotal. These results suggest that local EAT rather than regional or total adiposity may modulate endothelial dysfunction in patients with AF. PMID:24143210
Primary Structure of the Leukocyte Function-associated Molecule-1 Subunit: an Integrin with
Springer, Timothy A.
02115 Abstract. The leukocyte function-associated molecule 1 (LFA-1, CDlla/CD18) is a membrane molecule 1 (ICAM-1). LFA-1 consists of an ot subunit (Mr = 180,000) and a ~ subunit (Mr = 95,000). We and contain puta- tive divalent cation binding sites. LFA-1 has significant homology to the members
Sealing microcircuits with adhesives
NASA Technical Reports Server (NTRS)
Licari, J. J.; Perkins, K. L.
Report describes study of adhesive-sealed packages for hybrid microcircuits. Ten commercially available adhesives were used to seal metal and ceramic packages and were tested for moisture resistance at high humidity.
Neopterin-induced expression of intercellular adhesion molecule-1 (ICAM-1) in type II-like alveolar epithelial cells
Hoffmann, G; Rieder, J; Smolny, M; Seibel, M; Wirleitner, B; Fuchs, D; Schobersberger, W
Production and release of proinflammatory mediators such as tumour necrosis factor-alpha and neopterin are common events following the activation of the cellular immune system. Concerning inflammatory disorders of the lung, e.g. sepsis or sarcoidosis, high serum neopterin levels have been reported to correlate well with the severity of the disease. These situations are often associated with an increased expression of ICAM-1 reported to be induced in type II alveolar epithelial cells. In our study we investigated the potential effects of neopterin on ICAM-1 synthesis in the type II-like pneumocyte cell line L2. Detection of ICAM-1 gene expression by reverse transcriptase-polymerase chain reaction revealed a dose-dependent effect of neopterin, with maximum impact following 12-h incubations. Comparable results were obtained when ICAM-1 protein synthesis was measured via a cell-based ELISA. In a second set of experiments we were able to show that coincubation of L2 cells with pyrrolidine dithiocarbamate (PDTC) significantly suppressed neopterin-induced ICAM-1 synthesis. Since PDTC is known to be a potent inhibitor of NF-?B, the stimulating effects of neopterin on ICAM-1 gene expression and protein generation may be mediated by activation of this transcription factor. From these data we conclude that neopterin stimulates ICAM-1 production in L2 cells. In vivo, these effects may contribute to the prolongation of the inflammatory response, including cytotoxic cell host defence mechanisms that impair the functions of the airway epithelium. PMID:10594564
Intercellular Adhesion Molecule-1 in T cell differentiation and as a target for peptide therapy of type 1 diabetes
Dotson, Abby Louise
stored form of glucose) to glucose (22). When the blood glucose level becomes elevated, it induces the secretion of insulin from the ?-cells to promote glucose uptake by cells and the use of glucose for energy (22). The loss of blood glucose regulation...
Interleukin-6 and intercellular cell adhesion molecule-1 expression remains elevated in revived live endothelial cells following spaceflight.
Muid, S; Froemming, G R A; Ali, A M; Nawawi, H
The effects of spaceflight on cardiovascular health are not necessarily seen immediately after astronauts have returned but can be delayed. It is important to investigate the long term effects of spaceflight on protein and gene expression of inflammation and endothelial activation as a predictor for the development of atherosclerosis and potential cardiovascular problems. The objectives of this study were to investigate the (a) protein and gene expression of inflammation and endothelial activation, (b) expression of nuclear factor kappa B (NF?B), signal transducer and activator of transcription-3 (STAT-3) and endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC) 3 months post-space flight travel compared to ground controls. HUVEC cultured on microcarriers in fluid processing apparatus were flown to the International Space Station (ISS) by the Soyuz TMA-11 rocket. After landing, the cells were detached from microcarriers and recultured in T-25 cm(2) culture flasks (Revived HUVEC). Soluble protein expression of IL-6, TNF-?, ICAM-1, VCAM-1 and e-selectin were measured by ELISA. Gene expression of these markers and in addition NF?B, STAT-3 and eNOS were measured. Spaceflight induced IL-6 and ICAM-1 remain elevated even after 3 months post spaceflight travel and this is mediated via STAT-3 pathway. The downregulation of eNOS expression in revived HUVEC cells suggests a reduced protection of the cells and the surrounding vessels against future insults that may lead to atherosclerosis. It would be crucial to explore preventive measures, in relation to atherosclerosis and its related complications. PMID:24362480
Photocarcinogenesis and Inhibition of Intercellular Adhesion Molecule 1 Expression in Cells of DNA-Repair-Defective Individuals
Constanze Ahrens; Markus Grewe; Mark Berneburg; Susanne Grether-Beck; Xavier Quilliet; Mauro Mezzina; Alain Sarasin; Alan R. Lehmann; Colin F. Arlett; Jean Krutmann
Cells from patients with xeroderma pigmentosum complementation group D (XP-D) and most patients with trichothiodystrophy (TTD) are deficient in excision repair of ultraviolet (UV) radiation-induced DNA damage. Although in both syndromes this defect is based on mutations in the same gene, XPD, only XP-D, not TTD, individuals have an increased risk of skin cancer. Since the reduction in DNA repair
Engineering of Single Ig Superfamily Domain of Intercellular Adhesion Molecule 1 (ICAM-1) for Native Fold and Function*S
Springer, Timothy A.
and the ligand binding domain of LFA-1 called the inserted, or I, domain. Then, with a rational design approach that restored native folding of D1 in isolation were those that would convert hydrogen bond networks in buried interior with a conserved disulfide bond between -strands B and F. The N-terminal domain of ICAM-1 D1 has
Association of Intercellular Adhesion Moleculeq (ICAM-1) with Actin-containing Cytoskeleton and -actinin
Springer, Timothy A.
association of intercellular adhesion molecule-1 (ICAM-1, CD54), an integral membrane protein that functions of ICAM-1 with a glycophosphatidylinositol (GPI) anchor. Wild- type ICAM-1 appeared to localize most prominently in microvilli whereas GPI-ICAM-1 demonstrated a uniform cell surface distribution. Disruption
NASA Technical Reports Server (NTRS)
Bateman, W. A.
Cylindrical tubes joined together, end to end, by method employing adhesive, tapered ends, and spacing wires. Tapered joint between tubular structural elements provides pressure between bonding surfaces during adhesive curing. Spacing wires prevent adhesive from being scraped away when one element inserted in other. Method developed for assembling structural elements made of composite materials.
Pentoxifylline Decreases Serum Level of Adhesion Molecules in Atherosclerosis Patients
Mohammadpour, Amir Hooshang; Falsoleiman, Homa; Shamsara, Jamal; Abadi, Ghazaleh Allah; Rasooli, Ramin; Ramezani, Mohammad
Background: Inflammation is involved in development, progression, and complications of atherosclerotic disease. Clinical studies have indicated that the level of monocyte chemoattractant protein 1 (MCP-1), IL-18, and adhesion molecules correlates with the severity of atherosclerosis and can predict future cardiovascular events. Experimental studies have shown pentoxifylline (PTX) reduces these factors in animal models. The purpose of the present pilot study was to evaluate effect of PTX on a group of inflammatory biomarkers in patients with coronary artery disease (CAD). Methods: Forty patients with angiographically documented CAD, who fulfilled inclusion and exclusion criteria, were entered in the double-blind, randomized, pilot clinical study. The patients were randomly given PTX (400 mg three times daily) or placebo (3 tab/day) for 2 months. Serum concentrations of MCP-1, IL-18, intercellular adhesion Molecule 1 (ICAM-1), and vascular cell adhesion molecule 1Ā(VCAM-1) were measured before and at the end of intervention by enzyme-linked immunosorbant assay. Results: Our study showed that the serum levels of ICAM-1 and VCAM-1 was decreased in the study population after two-month treatment (P<0.05). Conclusion: Based on the results of our pilot study, administration of PTX in CAD patients significantly decreases adhesion molecules levels. PMID:24375159
Silicone pressure-sensitive adhesives with selective adhesion characteristics
Shaow B. Lin
The peel, probe tack, and loop tack adhesion characteristics of peroxide-cured silicone pressure-sensitive adhesives (PSAs) are investigated with respect to adhesive composition, peroxide concentration, and type of substrate. These adhesion properties decrease with increasing benzoyl peroxide concentration and their adhesion values vary noticeably with the substrate type. However, the loop adhesion to 'difficult-to-wet' surfaces (e.g. silicone-coated substrates) can be selectively
Comparison of cell adhesion molecule expression in cutaneous leucocytoclastic and lymphocytic vasculitis.
Burrows, N P; Molina, F A; Terenghi, G; Clark, P K; Haskard, D O; Polak, J M; Jones, R R
AIMS--To compare the expression of the cell adhesion molecules intercellular adhesion molecule-1 (ICAM-1), ELAM-1 (E-selectin), and vascular cell adhesion molecule-1 (VCAM-1) in cutaneous leucocytoclastic and lymphocytic vasculitis. METHODS--Immunohistochemical analysis was performed on early lesional skin biopsy specimens of leucocytoclastic vasculitis (n = 14), lymphocytic vasculitis (n = 10), non-lesional skin (n = 12), and normal skin (n = 5). A standard immunoperoxidase technique was used to detect expression of ICAM-1, E-selectin, VCAM-1, and the cell markers CD11a, CD11b, CD11c, von Willebrand factor, CD3, CD68, and neutrophil elastase (NP57). RESULTS--Basal keratinocyte intercellular adhesion molecule-1 was expressed in eight (80%) cases of lymphocytic and in only one (7%) case of leucocytoclastic vasculitis, and not in non-lesional skin or control biopsy specimens from normal subjects. E-selectin was expressed on vascular endothelium in eight (57%) cases of leucocytoclastic and in seven (70%) cases of lymphocytic vasculitis. Endothelial vascular cell adhesion molecule-1 expression was seen in three (21%) biopsy specimens of leucocytoclastic and five (50%) of lymphocytic vasculitis. There were increased numbers of cells in the dermal infiltrate stained for NP57, CD11b, and CD11c in leucocytoclastic compared with lymphocytic vasculitis (p < 0.001, p = 0.013, p = 0.009, respectively); immunoreactive positive cells for CD3 and CD11a were increased in lymphocytic compared with leucocytoclastic vasculitis (p < 0.001, p = 0.011, respectively). CONCLUSIONS--These observations indicate that upregulation of adhesion molecule expression occurs in both leucocytoclastic and lymphocytic vasculitis. The different patterns of adhesion molecule expression in the two groups of vasculitis may reflect differences in the local release of cytokines. In particular, detection of intercellular adhesion molecule-1 expression by keratinocytes in lymphocytic vasculitis is consistent with an active role for mediators derived from T lymphocytes in the pathogenesis of the lesion. Images PMID:7525658
Phospholipase D1 mediates lymphocyte adhesion and migration in experimental autoimmune encephalomyelitis.
G÷bel, Kerstin; Schuhmann, Michael K; Pankratz, Susann; Stegner, David; Herrmann, Alexander M; Braun, Attila; Breuer, Johanna; Bittner, Stefan; Ruck, Tobias; Wiendl, Heinz; Kleinschnitz, Christoph; Nieswandt, Bernhard; Meuth, Sven G
Lymphocyte adhesion and subsequent trafficking across endothelial barriers are essential steps in various immune-mediated disorders of the CNS, including MS. The molecular mechanisms underlying these processes, however, are still unknown. Phospholipase D1 (PLD1), an enzyme that generates phosphatidic acid through hydrolysis of phosphatidylcholine and additionally yields choline as a product, has been described as regulator of the cell mobility. By using PLD1-deficient mice, we investigated the functional significance of PLD1 for lymphocyte adhesion and migration in vitro and after myelin oligodendrocyte glycoprotein (MOG)35-55 -induced EAE, a model of human MS. The lack of PLD1 reduced chemokine-mediated static adhesion of lymphocytes to the endothelial adhesion molecules vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) in vitro, and was accompanied by a decreased migratory capacity in both blood brain barrier and cell migration models. Importantly, PLD1 is also relevant for the recruitment of immune cells into the CNS in vivo since disease severity after EAE was significantly attenuated in PLD1-deficient mice. Furthermore, PLD1 expression could be detected on lymphocytes in MS patients. Our findings suggest a critical function of PLD1-dependent intracellular signaling cascades in regulating lymphocyte trafficking during autoimmune CNS inflammation. PMID:24811005
Neuron adhesion and strengthening
NASA Astrophysics Data System (ADS)
Rocha, Aracely; Jian, Kuihuan; Ko, Gladys; Liang, Hong
Understanding the neuron/material adhesion is important for neuron stimulation and growth. The current challenges remain in the lack of precision of measuring techniques and understanding the behavior of neuron. Here, we report a fluid shear method to investigate adhesion at the neuron/poly-D-lysine interface. In this study, the adhesion of 12-day-old chick embryo-retina neurons cultured on poly-D-lysine coated glass coverslips was measured via parallel disk rotational flow. The shear stress experienced by the cells increases with the disk radius. There is a critical point along the radius (Rc) where the stress experienced by the neurons equals their adhesion. The measured Rc can be used to calculate the neuron adhesion. Our results demonstrate that neurons adhered to the poly-D-lysine had a strain hardening effect. The adhesive shear stress of the neuron-material increased with applied shear (?a). When the ?a reached or exceeded the value of 40 dyn/cm2, the adhesion remained constant at approximately 30 dyn/cm2. The present work allowed us not only to quantify the adhesive strength and force but also to evaluate the value of strain hardening at the neuron/poly-D-lysine interface.
NASA Technical Reports Server (NTRS)
Hill, S. G.; Sheppard, C. H.; Johnson, J. C.
A LARC-13 type adhesive system was developed and property data obtained that demonstrated improved thermomechanical properties superior to base LARC-13 adhesive. An improved adhesive for 589 K (600 F) use was developed by physical or chemical modification of LARC-13. The adhesive was optimized for titanium and composite bonding, and a compatible surface preparation for titanium and composite substrates was identified. The data obtained with the improved adhesive system indicated it would meet the 589 K (600 F) properties desired for application on space shuttle components. Average titanium lap shear data were: (1) 21.1 MPa (3355 psi) at RT, (2) 13.0 MPa (1881 psi) at 600 F, and (3) 16.4 MPa (2335) after aging 125 hours at 600 F and tested at 600 F.
Soluble adhesion molecules as markers for sepsis and the potential pathophysiological discrepancy in neonates, children and adults
Sepsis is a severe and life-threatening systemic inflammatory response to infection that affects all populations and age groups. The pathophysiology of sepsis is associated with aberrant interaction between leukocytes and the vascular endothelium. As inflammation progresses, the adhesion molecules that mediate these interactions become shed from cell surfaces and accumulate in the blood as soluble isoforms that are being explored as potential prognostic disease biomarkers. We critically review the studies that have tested the predictive value of soluble adhesion molecules in sepsis pathophysiology with emphasis on age, as well as the underlying mechanisms and potential roles for inflammatory shedding. Five soluble adhesion molecules are associated with sepsis, specifically, E-selectin, L-selectin and P-selectin, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. While increased levels of these soluble adhesion molecules generally correlate well with the presence of sepsis, their degree of elevation is still poorly predictive of sepsis severity scores, outcome and mortality. Separate analyses of neonates, children and adults demonstrate significant age-dependent discrepancies in both basal and septic levels of circulating soluble adhesion molecules. Additionally, a range of both clinical and experimental studies suggests protective roles for adhesion molecule shedding that raise important questions about whether these should positively or negatively correlate with mortality. In conclusion, while predictive properties of soluble adhesion molecules have been researched intensively, their levels are still poorly predictive of sepsis outcome and mortality. We propose two novel directions for improving clinical utility of soluble adhesion molecules: the combined simultaneous analysis of levels of adhesion molecules and their sheddases; and taking age-related discrepancies into account. Further attention to these issues may provide better understanding of sepsis pathophysiology and increase the usefulness of soluble adhesion molecules as diagnostic and predictive biomarkers. PMID:24602331
Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin
Background Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Methods Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-?B activation, and hence cell adhesion to human umbilical vein endothelial cells (HUVECs). 5-Aminoimidazole-4-carboxamide 1-?-D-ribofuranoside (AICAR), an AMP-activated protein kinase (AMPK) activator, was used to determine the regulatory role of AMPK on HCC adhesion to the endothelium in regard to the resistin effects. Results Treatment with resistin increased the adhesion of SK-Hep1 cells to HUVECs and concomitantly induced NF-?B activation, as well as ICAM-1 and VCAM-1 expressions in SK-Hep1 cells. Using specific blocking antibodies and siRNAs, we found that resistin-induced SK-Hep1 cell adhesion to HUVECs was through NF-?B-regulated ICAM-1 and VCAM-1 expressions. Moreover, treatment with AICAR demonstrated that AMPK activation in SK-Hep1 cells significantly attenuates the resistin effect on SK-Hep1 cell adhesion to HUVECs. Conclusions These results clarify the role of resistin in inducing HCC adhesion to the endothelium and demonstrate the inhibitory effect of AMPK activation under the resistin stimulation. Our findings provide a notion that resistin play an important role to promote HCC metastasis and implicate AMPK may be a therapeutic target to against HCC metastasis. PMID:24555415
House dust mite allergen Der p 1 elevates the release of inflammatory cytokines and expression of adhesion molecules in co-culture of human eosinophils and bronchial epithelial cells
Chun K. Wong; Mandy L. Y. Li; Cheng B. Wang; Wai K. Ip; Ya P. Tian; Christopher W. K. Lam
House dust mite (HDM) is a common allergen of allergic asthma. Eosinophils are principal effector cells of allergic inflammation and their adhesion onto human bronchial epithelial cells is mediated by a CD18-intracellular adhesion molecule-1 (ICAM-1)-dependent interaction. We studied the effects of HDM Dermatophagoides pteronyssinus (Der p) 1 on the activation of eosinophils and bronchial epithelial BEAS-2B cells. Cytokines and adhesion
NASA Technical Reports Server (NTRS)
Patterson, Jonathan D.
Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.
NSDL National Science Digital Library
New Jersey
Learners explore water adhesion and learn about why water molecules are more strongly attracted to some substances than others. In an investigation titled "Fabric Frenzy," learners use a magnifying glass to examine different fabrics and hypothesize whether each kind would be good for soaking up water. Learners then weigh the dry fabrics, predict how water will affect the weight of each sample, wet the samples, and weigh them again to see how much water they in fact absorb. Learners also examine other liquids and compare their adhesion to water adhesion.
NASA Astrophysics Data System (ADS)
Walton, Otis R.
This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.
NASA Technical Reports Server (NTRS)
Walton, Otis R.
This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.
A role for cell adhesion in beryllium-mediated lung disease
Hong-geller, Elizabeth [Los Alamos National Laboratory
Chronic beryllium disease (CBD) is a debilitating lung disorder in which exposure to the lightweight metal beryllium (Be) causes the accumulation of beryllium-specific CD4+ T cells in the lung and formation of noncaseating pulmonary granulomas. Treatment for CBD patients who exhibit progressive pulmonary decline is limited to systemic corticosteroids, which suppress the severe host inflammatory response. Studies in the past several years have begun to highlight cell-cell adhesion interactions in the development of Be hypersensitivity and CBD. In particular, the high binding affinity between intercellular adhesion molecule 1 (I-CAM1) on lung epithelial cells and the {beta}{sub 2} integrin LFA-1 on migrating lymphocytes and macrophages regulates the concerted rolling of immune cells to sites of inflammation in the lung. In this review, we discuss the evidence that implicates cell adhesion processes in onset of Be disease and the potential of cell adhesion as an intervention point for development of novel therapies.
Carvedilol prevents low-density lipoprotein (LDL)-enhanced monocyte adhesion to endothelial cells by inhibition of LDL oxidation.
Yue, T L; Wang, X; Gu, J L; Ruffolo, R R; Feuerstein, G Z
Cultured human umbilical vein endothelial cells oxidize low-density lipoproteins (LDL), assessed as increase in thiobarbituric acid reactive substance formation and oxidized LDL-induced cytotoxicity (lactate dehydrogenase (LDH) release). Endothelial cell-generated oxidized also enhances the adhesiveness of endothelial cells to monocytes. Carvedilol, a new vasodilating beta-adrenoceptor antagonist, inhibits the oxidation of LDL by endothelial cells and reduces oxidized LDL-induced LDH release from endothelial cells in a concentration-dependent manner with IC50 values of 2.56 and 1.38 microM, respectively. Moreover, carvedilol inhibits oxidized LDL-induced adhesion of monocytes to the endothelial cells in a similar concentration-dependent manner. Under the same conditions, propranolol, atenolol, pindolol and labetalol had only weak or no consistent effects on both LDL oxidation by endothelial cells and adhesion of monocytes to the endothelial cells. Monoclonal antibodies against human intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) or E-selectin (ELAM-1) partially blocked oxidized LDL-stimulated adhesion of endothelial cells to monocytes. The inhibitory effects of carvedilol on LDL oxidation and monocyte adhesion to endothelial cells may protect blood vessels from atherosclerotic processes associated with oxidized LDL-induced injuries. PMID:8750722
Anti-inflammatory drugs and endothelial cell adhesion molecule expression in murine vascular beds
Mori, N; Horie, Y; Gerritsen, M; Anderson, D; Granger, D
BackgroundŚInflammatory bowel diseases (IBD) are characterised by an intense infiltration of leucocytes that is mediated by adhesion molecules expressed on the surface of activated endothelial cells. ?AimsŚTo determine whether drugs used in the treatment of IBD, specifically dexamethasone (DEX), 5-aminosalicylic acid (5-ASA), methotrexate (MTX), and 6-mercaptopurine (6-MP), alter the expression of endothelial cell adhesion molecules (ECAMs). ?MethodsŚThe expression of P-selectin, E-selectin, intercellular adhesion molecule 1 (ICAM-1), and vascular CAM 1(VCAM-1) in different vascular beds of C57Bl/6J mice was measured using the dual radiolabelled monoclonal antibody technique. ?ResultsŚLipopolysaccharide (LPS) elicited a profound increase in the expression of all ECAMs in the mesentery, small intestine, caecum, and distal colon. The LPS induced increase in CAM expression was not significantly affected by prior treatment with either MTX or 6-MP. However, pretreatment with either DEX or 5-ASA significantly attenuated LPS induced increases in expression of P- and E-selectin, and VCAM-1 in the majority of tissues evaluated. DEX also blunted the LPS induced increase in ICAM-1 expression in the caecum and distal colon. DEX, but not 5-ASA, largely abolished the rise in plasma tumour necrosis factor ? elicited by LPS. ?ConclusionsŚThese findings suggest that DEX and 5-ASA may exert their beneficial therapeutic action in IBD, at least in part, by inhibiting the expression of ECAMs which mediate leucocyte adhesion and transmigration in the microvasculature. ?? Keywords: P-selectin; E-selectin; intercellular adhesion molecule 1; vascular cell adhesion molecule 1; dexamethasone; 5-aminosalicylic acid PMID:9895377
Association of Intercellular Adhesion Moleculeq (ICAM-1) with Actin-containing Cytoskeleton and -actinin
Peter Pallai; Donald E. Staunton; Timothy A. Springer
We have studied the cytoskeletal association of intercellular adhesion molecule-1 (ICAM-1, CD54), an integral membrane protein that functions as a coun- terreceptor for leukocyte integrins (CDll\\/CDI8). A linkage between ICAM-1 and cytoskeletal elements was suggested by studies showing a different ICAM-1 staining pattern for COS cells transfected with wild- type ICAM-1 or with an ICAM-1 construct that replaces the cytoplasmic
Combinatorial Investigations of Polymer Adhesion
NSDL National Science Digital Library
Crosby, Alfred
In this work, we introduce a combinatorial technique that can be used to investigate adhesive interactions between a polymer and either another polymer, a ceramic, or a metal. The primary goal in the development of this technique is to design a high-throughput, parallel processing adhesion test that allows the adhesive strength dependence on multivariable environments to be determined. This combinatorial polymer adhesion test will provide qualitative and quantitative data used to determine absolute measures of adhesion as a function of the multidimensional parameter space. These results will aid industrial screening for optimal adhesives, as well as provide a unique tool for gaining a fundamental understanding of polymer adhesion. We investigate the temperature and thickness dependence of the self-adhesion of polystyrene (PS) and the adhesion between PS and poly(dimethylsiloxane) (PDMS) for demonstration of concept.
Regulation of Cell Adhesion Strength by Peripheral Focal Adhesion Distribution
Elineni, KranthiĀKumar; Gallant, NathanĀD.
Cell adhesion to extracellular matrices is a tightly regulated process that involves the complex interplay between biochemical and mechanical events at the cell-adhesive interface. Previous work established the spatiotemporal contributions ofĀadhesive components to adhesion strength and identified a nonlinear dependence on cell spreading. This study was designed to investigate the regulation of cell-adhesion strength by the size and position of focal adhesions (FA). The cell-adhesive interface was engineered to direct FA assembly to the periphery of the cell-spreading area to delineate the cell-adhesive area from the cell-spreading area. It was observed that redistributing the same adhesive area over a larger cell-spreading area significantly enhanced cell-adhesion strength, but only up to a threshold area. Moreover, the size of the peripheral FAs, which was interpreted as an adhesive patch, did not directly govern the adhesion strength. Interestingly, this is in contrast to the previously reported functional role of FAs in regulating cellular traction where sizes of the peripheral FAs play a critical role. These findings demonstrate, to our knowledge for the first time, that two spatial regimes in cell-spreading area exist that uniquely govern the structure-function role of FAs in regulating cell-adhesion strength. PMID:22208188
Ruggeri, Zaverio M.
Platelet adhesive mechanisms play a well-defined role in hemostasis and thrombosis, but evidence continues to emerge for a relevant contribution to other pathophysiological processes including inflammation, immune-mediated responses to microbial and viral pathogens, and cancer metastasis. Hemostasis and thrombosis are related aspects of the response to vascular injury, but the former protects from bleeding after trauma while the latter is a disease mechanism. In either situation, adhesive interactions mediated by specific membrane receptors support the initial attachment of single platelets to cellular and extracellular matrix constituents of the vessel wall and tissues. In the subsequent steps of thrombus growth and stabilization, adhesive interactions mediate platelet to platelet cohesion (aggregation) and anchoring to the fibrin clot. A key functional aspect of platelets is their ability to circulate in a quiescent state surveying the integrity of the inner vascular surface, coupled to a prompt reaction wherever alterations are detected. In many respects, therefore, platelet adhesion to vascular wall structures, to one another or to other blood cells are facets of the same fundamental biological process. The adaptation of platelet adhesive functions to the effects of blood flow is the main focus of this review. PMID:19191170
Complement activation and kidney injury molecule-1-associated proximal tubule injury in severe preeclampsia.
Burwick, Richard M; Easter, Sarah Rae; Dawood, Hassan Y; Yamamoto, Hidemi S; Fichorova, Raina N; Feinberg, Bruce B
Kidney injury with proteinuria is a characteristic feature of preeclampsia, yet the nature of injury in specific regions of the nephron is incompletely understood. Our study aimed to use existing urinary biomarkers to describe the pattern of kidney injury and proteinuria in pregnancies affected by severe preeclampsia. We performed a case-control study of pregnant women from Brigham and Women's Hospital from 2012 to 2013. We matched cases of severe preeclampsia (n=25) 1:1 by parity and gestational age to 2 control groups with and without chronic hypertension. Urinary levels of kidney injury molecule-1 and complement components (C3a, C5a, and C5b-9) were measured by enzyme-linked immunosorbent assay, and other markers (albumin, ?2 microglobulin, cystatin C, epithelial growth factor, neutrophil gelatinase-associated lipocalin, osteopontin, and uromodulin) were measured simultaneously with a multiplex electrochemiluminescence assay. Median values between groups were compared with the Wilcoxon signed-rank test and correlations with Spearman correlation coefficient. Analysis of urinary markers revealed higher excretion of albumin and kidney injury molecule-1 and lower excretion of neutrophil gelatinase-associated lipocalin and epithelial growth factor in severe preeclampsia compared with chronic hypertension and healthy controls. Among subjects with severe preeclampsia, urinary excretion of complement activation products correlated most closely with kidney injury molecule-1, a specific marker of proximal tubule injury (C5a: r=0.60; P=0.001; and C5b-9: r=0.75; P<0.0001). Taken together, we describe a pattern of kidney injury in severe preeclampsia that is characterized by glomerular impairment and complement-mediated inflammation and injury, possibly localized to the proximal tubule in association with kidney injury molecule-1. PMID:24958504
Adhesion in Nanodiamond Particles
NASA Astrophysics Data System (ADS)
Aravind, Vasudeva; Lutkus, Luke; Legum, Benjamin; Clarion Collaboration
Due to their excellent mechanical properties and biologically non-toxic nature, nanodiamonds show great promise for applications in tribology, lubrication, drug delivery, tissue scaffolds and surgical implants. In order to design effective nanocomposites and other biomedical systems exploiting these properties, it is important to understand the properties and mechanisms by which nanodiamonds adhere to other materials, and how they behave at interfaces. In this article, the adhesive force between nanodiamond particles and the silicon scanning probe microscope tip are reported. The adhesive force can be correlated to the purity and functionalization of nanodiamond surface, and the values range from 0.1nN to 2.0nN for the samples studied. It is observed that the lateral forces applied by the scanning probe tip can cause the adhesive forces to increase by an order of magnitude from 0.1 to 2.0nN at regions where the tip experiences maximum contact force.
Protein mediated membrane adhesion
NASA Astrophysics Data System (ADS)
Carlson, Andreas; Mahadevan, L.
Adhesion in the context of mechanical attachment, signaling, and movement in cellular dynamics is mediated by the kinetic interactions between membrane-embedded proteins in an aqueous environment. Here, we present a minimal theoretical framework for the dynamics of membrane adhesion that accounts for the kinetics of protein binding, the elastic deformation of the membrane, and the hydrodynamics of squeeze flow in the membrane gap. We analyze the resulting equations using scaling estimates to characterize the spatiotemporal features of the adhesive patterning and corroborate them using numerical simulations. In addition to characterizing aspects of cellular dynamics, our results might also be applicable to a range of phenomena in physical chemistry and materials science where flow, deformation, and kinetics are coupled to each other in slender geometries.
Klebanoff, Leonard Elliott (Dublin, CA); Rader, Daniel John (Albuquerque, NM); Walton, Christopher (Berkeley, CA); Folta, James (Livermore, CA)
An efficient device for capturing fast moving particles has an adhesive particle shield that includes (i) a mounting panel and (ii) a film that is attached to the mounting panel wherein the outer surface of the film has an adhesive coating disposed thereon to capture particles contacting the outer surface. The shield can be employed to maintain a substantially particle free environment such as in photolithographic systems having critical surfaces, such as wafers, masks, and optics and in the tools used to make these components, that are sensitive to particle contamination. The shield can be portable to be positioned in hard-to-reach areas of a photolithography machine. The adhesive particle shield can incorporate cooling means to attract particles via the thermophoresis effect.
Switchable bio-inspired adhesives
NASA Astrophysics Data System (ADS)
Kroner, Elmar
Geckos have astonishing climbing abilities. They can adhere to almost any surface and can run on walls and even stick to ceilings. The extraordinary adhesion performance is caused by a combination of a complex surface pattern on their toes and the biomechanics of its movement. These biological dry adhesives have been intensely investigated during recent years because of the unique combination of adhesive properties. They provide high adhesion, allow for easy detachment, can be removed residue-free, and have self-cleaning properties. Many aspects have been successfully mimicked, leading to artificial, bio-inspired, patterned dry adhesives, and were addressed and in some aspects they even outperform the adhesion capabilities of geckos. However, designing artificial patterned adhesion systems with switchable adhesion remains a big challenge; the gecko's adhesion system is based on a complex hierarchical surface structure and on advanced biomechanics, which are both difficult to mimic. In this paper, two approaches are presented to achieve switchable adhesion. The first approach is based on a patterned polydimethylsiloxane (PDMS) polymer, where adhesion can be switched on and off by applying a low and a high compressive preload. The switch in adhesion is caused by a reversible mechanical instability of the adhesive silicone structures. The second approach is based on a composite material consisting of a Nickel- Titanium (NiTi) shape memory alloy and a patterned adhesive PDMS layer. The NiTi alloy is trained to change its surface topography as a function of temperature, which results in a change of the contact area and of alignment of the adhesive pattern towards a substrate, leading to switchable adhesion. These examples show that the unique properties of bio-inspired adhesives can be greatly improved by new concepts such as mechanical instability or by the use of active materials which react to external stimuli.
Individual and Neighborhood Socioeconomic Status and Inflammation in Mexican-American Women: What is the Role of Obesity?
Gallo, Linda C.; Fortmann, Addie L.; de los Monteros, Karla Espinosa; Mills, Paul J.; Barrett-Connor, Elizabeth; Roesch, Scott C.; Matthews, Karen A.
Objective Inflammation may represent a biological mechanism underlying associations of socioeconomic status (SES) with cardiovascular disease (CVD). The current study examined relationships of individual and neighborhood SES with inflammatory markers in Mexican-American women and evaluated contributions of obesity and related heath behaviors to these associations. Methods A random sample of 284 Mexican-American women (mean age 49.74 years) was recruited from socioeconomically diverse South San Diego communities. Women completed measures of sociodemographic characteristics and health behaviors, and a physical examination with fasting blood draw for assay of plasma C-reactive-protein (CRP), interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1 (sICAM-1). Neighborhood SES was extracted from the US Census Bureau 2000 database. Results In multilevel models, a one-standard deviation (SD) higher individual and neighborhood SES related to a 27.35% and 23.56% lower CRP (ps < .01), a 7.04% and 5.32% lower sICAM-1 (ps < .05), and a 10.46% (p < .05) and 2.40% lower IL-6 level (NS), respectively. Controlling for individual SES, a one-SD higher neighborhood SES related to a 18.05% lower CRP (p = .07); there was no unique effect of neighborhood SES for IL-6 or sICAM-1. Differences in body mass index, waist circumference, and dietary fat consumption contributed significantly to SES-inflammation associations. Conclusions The findings support a link between SES and inflammatory markers in Mexican-American women, and implicate obesity and dietary fat in these associations. Additional effects of neighborhood SES were not statistically significant. These findings should be viewed tentatively because the relatively small sample size limits the evaluation of multiple contextual factors. PMID:22582313
Elastomer toughened polyimide adhesives
NASA Technical Reports Server (NTRS)
St.clair, A. K.; St.clair, T. L. (inventors)
A rubber-toughened addition-type polyimide composition is disclosed which has excellent high temperature bonding characteristics in the fully cured state, and improved peel strength and adhesive fracture resistance physical property characteristics. The process for making the improved adhesive involves preparing the rubber containing amic acid prepolymer by chemically reacting an amine-terminated elastomer and an aromatic diamine with an aromatic dianhydride with which a reactive chain stopper anhydride was mixed, and utilizing solvent or mixture of solvents for the reaction.
Biomimetic Adhesive Polymers Based on Mussel Adhesive Proteins
Nature provides many outstanding examples of adhesive strategies from which chemists and material scientists can draw inspiration in their pursuit of new adhesive materials. As described in other chapters of this book, detailed studies of the adhesive mechanisms of geckos, mussels and other organisms during the past several decades have enhanced our understanding of the underlying physicochemical principles to the
NASA Technical Reports Server (NTRS)
Lemons, C. R.; Salmassy, O. K.
Bonding method, which reduces amount and weight of adhesive, is applicable to foam-filled honeycomb constructions. Novel features of process include temperature-viscosity control and removal of excess adhesive by transfer to cellophane film.
Adhesive for cryogenic temperature applications
NASA Technical Reports Server (NTRS)
Doyle, H. M.
Adhesive, which bonds a metal liner to a filament wound composite structure used for cryogenic pressure vessels, prevents the metal liner from buckling under depressurization. The adhesive consists of adducts of urethane and epoxy resins.
Mechanisms of Adhesion in Geckos
SYNOPSIS. The extraordinary adhesive capabilities of geckos have challenged explanation for millennia, since Aristotle first recorded his observations. We have discovered many of the secrets of gecko adhesion, yet the millions of dry, adhesive setae on the toes of geckos continue to generate puzzling new questions and valuable answers. Each epidermally-derived, keratinous seta ends in hundreds of 200 nm spatular
Chaffee-Cipich, Michelle N; Sturtevant, Bryce D; Beaudoin, Stephen P
It is of increasing importance to understand how explosive particles adhere to surfaces in order to understand how to remove them for detection in airport or other security settings. In this study, adhesion forces between royal demolition explosive (cyclotrimethylenetrinitramine) (RDX), pentaerythritol tetranitrate (PETN), and trinitrotoluene (TNT) in their crystalline forms and aluminum coupons with three finishes, acrylic melamine (clear coating), polyester acrylic melamine (white coating) automotive finishes, and a green military-grade finish, were measured and modeled. The force measurements were performed using the atomic force microscopy (AFM)-based colloidal probe microscopy (CPM) method. Explosive particles were mounted on AFM cantilevers and repeatedly brought in and out of contact with the surfaces of interest while the required force needed to pull out of contact was recorded. An existing Matlab-based simulator was used to describe the observed adhesion force distributions, with excellent agreement. In these simulations, the measured topographies of the interacting surfaces were considered, although the geometries were approximated. The simulations were performed using a van der Waals force-based adhesion model and a composite effective Hamaker constant. It was determined that certain combinations of roughness on the interacting surfaces led to preferred particle-substrate orientations that produced extreme adhesion forces. PMID:23510004
Rapid adhesive bonding concepts
NASA Technical Reports Server (NTRS)
Stein, B. A.; Tyeryar, J. R.; Hodges, W. T.
Adhesive bonding in the aerospace industry typically utilizes autoclaves or presses which have considerable thermal mass. As a consequence, the rates of heatup and cooldown of the bonded parts are limited and the total time and cost of the bonding process is often relatively high. Many of the adhesives themselves do not inherently require long processing times. Bonding could be performed rapidly if the heat was concentrated in the bond lines or at least in the adherends. Rapid adhesive bonding concepts were developed to utilize induction heating techniques to provide heat directly to the bond line and/or adherends without heating the entire structure, supports, and fixtures of a bonding assembly. Bonding times for specimens are cut by a factor of 10 to 100 compared to standard press bonding. The development of rapid adhesive bonding for lap shear specimens (per ASTM D1003 and D3163), for aerospace panel bonding, and for field repair needs of metallic and advanced fiber reinforced polymeric matrix composite structures are reviewed.
Labial adhesion and bacteriuria
Azarfar, Anoush; Ravanshad, Yalda; Bagheri, Sepideh; Esmaeeli, Mohammad; Nejad, Mahmood Malek
Objective The purpose of this study is to evaluate the clinical presentation, laboratory findings, and response to treatment in girls with labial adhesion younger than 23 months. Material and Methods A retrospective chart review of all girls younger than 23 months with the diagnosis of labial adhesion was referred to Dr Sheikh childrenÆs clinic in Mashhad in northeast Iran between 1998 and 2013. Results Sixty-three patients were diagnosed with labial adhesion during the review period. Most patients were diagnosed by physicians during the physical examination or during the evaluation for their voiding problems. The most prevalent symptom among patients was dysuria and restlessness while voiding. Twenty-one (33.3%) patients had a history of urinary tract infection. 17 (26.9%) patients had sterile pyuria and 69.8% showed presence of bacteria in their urine samples. Conclusion Physicians may frequently encounter pre-pubertal girls whose urinalysis may show sterile pyuria or presence of bacteria with colony counts <105 in the absence of urinary tract infection symptoms. In these cases, labial adhesion should always be suspected and genital examination should be performed. PMID:26097386
p85-RhoGDI2, a novel complex, is required for PSGL-1-induced ?1 integrin-mediated lymphocyte adhesion to VCAM-1.
Luo, Jixian; Xu, Tingshuang; Li, Chunfeng; Ba, Xueqing; Wang, Xiaoguang; Jiang, Yong; Zeng, Xianlu
P-selectin glycoprotein ligand-1 and ?1 integrin play essential roles in T cell trafficking during inflammation. E-selectin and vascular cell adhesion molecule-1 are their ligands expressed on inflammation-activated endothelium. During the tethering and rolling of lymphocytes on endothelium, P-selectin glycoprotein ligand-1 binds E-selectin and induces signals. Subsequently, ?1 integrin is activated and mediates stable adhesion. However, the intracellular signal pathways from PSGL-1 to ?1 integrin have not yet been fully understood. Here, we find that p85, a regulatory subunit of phosphoinositide 3-kinase, forms a novel complex with Rho-GDP dissociation inhibitor-2, a lymphocyte-specific RhoGTPases dissociation inhibitor. Phosporylations of the p85-bound Rho-GDP dissociation inhibitor-2 on 130 and 153 tyrosine residues by c-Abl and Src were required for the complex to be recruited to P-selectin glycoprotein ligand-1 and thereby regulate ?1 integrin-mediated T cell adhesion to vascular cell adhesion molecule-1. Both shRNAs to Rho-GDP dissociation inhibitor-2 and p85 and over-expression of Rho-GDP dissociation inhibitor-2 Y130F and Y153F significantly reduced the above-mentioned adhesion. Although Rho-GDP dissociation inhibitor-2 in the p85-Rho-GDP dissociation inhibitor-2 complex was also phosphorylated on 24 tyrosine residue by Syk, the phosphorylation is not required for the adhesion. Taken together, we find that specific phosphorylations on 130 and 153 tyrosine residues of p85-bound Rho-GDP dissociation inhibitor-2 are pivotal for P-selectin glycoprotein ligand-1-induced ?1 integrin-mediated lymphocyte adhesion to vascular cell adhesion molecule-1. This will shed new light on the mechanisms that connect leukocyte initial rolling with subsequent adhesion. PMID:24055812
Mycobacterium tuberculosis alters expression of adhesion molecules on monocytic cells.
L¾pez RamĒrez, G M; Rom, W N; Ciotoli, C; Talbot, A; Martiniuk, F; Cronstein, B; Reibman, J
The host response to Mycobacterium tuberculosis is characterized by interactions between mononuclear cells, with recruitment and fusion of these cells culminating in granuloma formation. In addition, the host response to M. tuberculosis requires CD4+ T-cell reactivity, mediated by antigen-independent as well as antigen-dependent mechanisms. Thus, we hypothesized that cell adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1; CD54) would participate in the response to infection with M. tuberculosis. Exposure of THP-1 cells derived from a monocyte/macrophage cell line to M. tuberculosis (1:1 bacterium/cell ratio) elicited a sustained increase (660% +/- 49% above resting level) in the expression of ICAM-1 that continued for at least 72 h. Neither the expression of vascular cell adhesion molecule 1 (VCAM-1; CD106) nor that of the integrins lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) or CR3 (CD11b/CD18) was increased to a similar extent at corresponding time points. The increase in ICAM-1 protein expression was accompanied by an increase in steady-state mRNA (Northern [RNA] analysis). Neutralizing monoclonal antibodies directed against tumor necrosis factor alpha but not interleukin 1 alpha or interleukin 1 beta substantially abrogated the response to M. tuberculosis consistent with a paracrine or autocrine response. Continuous upregulation of the expression of ICAM-1 on mononuclear phagocytes induced by M. tuberculosis may mediate the recruitment of monocytes and enhance the antigen presentation of M. tuberculosis, thus permitting the generation and maintenance of the host response. PMID:7910594
Adhesion mechanics of ivy nanoparticles.
Wu, Yu; Zhao, Xiaopeng; Zhang, Mingjun
Adhesion mechanism of ivy has been of major research interest for its potential applications in high-strength materials. Recent experimental studies demonstrated that nanoparticles secreted from ivy tendrils play an important role in adhesion. In this work, we investigate how various factors such as van der Waals interaction, capillarity, and molecular cross-linking influence the adhesion mechanics of ivy nanoparticles. This paper provides guidelines in choosing different adhesive contact models. Understanding the mechanics of ivy adhesion could potentially inspire the design and fabrication of novel nano-bio-materials. PMID:20070973
Biological adhesives and fastening devices
NASA Astrophysics Data System (ADS)
Wolpert, H. D.
Sea creatures are a leading source to some of the more interesting discoveries in adhesives. Because sea water naturally breaks down even the strongest conventional adhesive, an alternative is important that could be used in repairing or fabricating anything that might have regular contact with moisture such as: Repairing broken and shattered bones, developing a surgical adhesive, use in the dental work, repairing and building ships, and manufacturing plywood. Some of nature's prototypes include the common mussel, limpet, some bacteria and abalone. As we learn more about these adhesives we are also developing non adhesive fasteners, such as mimicked after studying the octopus, burdock burrs (i.e. Velcro«) and the gecko.
Alkaloids of Nitraria sibirica Pall. decrease hypertension and albuminuria in angiotensin II-salt hypertension.
Bakri, Mahinur; Yi, Yang; Chen, Ling-Dan; Aisa, Haji Akber; Wang, Mong-Heng
In traditional Chinese medicine, Nitraria sibirica Pall. (Nitrariaceae) is used to treat hypertension. This study determined the effects of the total alkaloids of the leaves of Nitraria sibirica (NSTA) on blood pressure and albuminuria in mice treated with angiotensin II and a high-salt diet (ANG/HS). Adult mice were divided into three groups: control; infused with angiotensin II and fed a diet containing 4% NaCl (ANG/HS; and ANG/HS plus injection of NSTA (1 mgĘkg(-1)Ęd(-1), i.p.). After treatment of these regimens, daily water and food intake, kidney weight, blood pressure, urinary albumin excretion, renal concentrations of inflammatory markers, including soluble intercellular adhesion molecule-1 (sICAM-1) and monocyte chemoattractant protein-1 (MCP-1), and the expression of renal fibrosis markers were determined. Compared to the control group, the ANG/HS group had higher blood pressure and urinary albumin excretion. Treatment with NSTA in ANG/HS mice for three weeks significantly reduced blood pressure and urinary albumin excretion. ANG/HS treatment caused elevated levels of sICAM-1 and MCP-1, as well as increased fibrosis markers. Concurrent treatment with ANG/HS and NSTA attenuated the levels and expression of renal inflammatory and fibrosis markers. Treatment with NSTA effectively reduces hypertension-induced albuminuria through the reduction of renal inflammatory and fibrosis markers. PMID:24863351
Adhesion behaviors on superhydrophobic surfaces.
Zhu, Huan; Guo, Zhiguang; Liu, Weimin
The adhesion behaviors of superhydrophobic surfaces have become an emerging topic to researchers in various fields as a vital step in the interactions between materials and organisms/materials. Controlling the chemical compositions and topological structures via various methods or technologies is essential to fabricate and modulate different adhesion properties, such as low-adhesion, high-adhesion and anisotropic adhesion on superhydrophobic surfaces. We summarize the recent developments in both natural superhydrophobic surfaces and artificial superhydrophobic surfaces with various adhesions and also pay attention to superhydrophobic surfaces switching between low- and high-adhesion. The methods to regulate or translate the adhesion of superhydrophobic surfaces can be considered from two perspectives. One is to control the chemical composition and change the surface geometric structure on the surfaces, respectively or simultaneously. The other is to provide external stimulations to induce transitions, which is the most common method for obtaining switchable adhesions. Additionally, adhesion behaviors on solid-solid interfaces, such as the behaviors of cells, bacteria, biomolecules and icing on superhydrophobic surfaces are also noticeable and controversial. This review is aimed at giving a brief and crucial overview of adhesion behaviors on superhydrophobic surfaces. PMID:24575424
Environmentally compliant adhesive joining technology
Tira, J.S.
Adhesive joining offers one method of assembling products. Advantages of adhesive joining/assembly include distribution of applied forces, lighter weight, appealing appearance, etc. Selecting environmentally safe adhesive materials and accompanying processes is paramount in today`s business climate if a company wants to be environmentally conscious and stay in business. Four areas of adhesive joining (adhesive formulation and selection, surface preparation, adhesive bonding process, waste and pollution generation/cleanup/management) all need to be carefully evaluated before adhesive joining is selected for commercial as well as military products. Designing for six sigma quality must also be addressed in today`s global economy. This requires material suppliers and product manufacturers to work even closer together.
Adhesion Molecule Polymorphisms and Pulse Wave Velocity in American Youth
Zhu, Haidong; Yan, Weili; Tan, Yuande; Li, Ke; Kapuku, Gaston; Treiber, Frank A.; Su, Shaoyong; Harshfield, Gregory A.; Snieder, Harold; Dong, Yanbin
Background Our research group recently reported that aorto-radial (radial) and aorto-dorsalis-pedis (foot) pulse wave velocity (PWV) as proxies of arterial stiffness are substantially heritable in healthy youth. This paper aimed at uncovering the genetic contributions of adhesion molecules, key members in the inflammatory process, to PWV in these young individuals. Methods Radial and foot PWV were non-invasively measured with applanation tonometry in 702 black and white subjects (42% blacks, mean age 17.7 ▒3.3 years) from the Georgia Cardiovascular Twin Study. Eight functional polymorphisms from genes for E-selectin (SELE), P-selectin (SELP), intercellular adhesion molecules-1 (ICAM1), and vascular cell adhesion molecules-1 (VCAM1) were genotyped. Results Youth with Ser290Asn or Asn290Asn genotype (SELP) compared to those with Ser290Ser had an increase in both radial and foot PWV (6.61▒0.07 vs. 6.41▒0.05 m/s, p=0.026; 7.22▒0.05 vs. 7.04▒0.04 m/s, p=0.007). TT homozygotes of rs2244529 (SELP) had higher foot PWV (7.28▒0.07 vs. 7.06▒0.03 m/s, p=0.002) than CT heterozygotes and CC homozygotes. There appeared to be a decrease in foot PWV in youth with the 241Arg allele (ICAM1) as compared to those without (6.96▒0.08 vs. 7.14▒0.03 m/s, p=0.005). For the Asp693Asp (C to T) polymorphism (VCAM1), CC genotype had higher foot PWV than CT and TT genotypes (7.18▒0.04 vs. 6.95▒0.06 m/s, p<0.0001). There was an epistatic interaction between Ser290Asn, Gly241Arg, and Asp693Asp on foot PWV (p=0.017), explaining 3.6% variance of the foot PWV. Conclusion Genetic variation of adhesion molecules may be implicated in the development of arterial stiffness. Screening for adhesion molecule polymorphisms may help identify high-risk youth. PMID:18828734
NASA Technical Reports Server (NTRS)
Blatz, P. S.; Gibbs, H. H.
A polyimide precursor adhesive solution, code-named NR-056X, was developed. It reproducibly gives low void, high strength bond lines at both room temperature and 589K (600 F) using either titanium or graphite/polyimide composite adherends having 12.7 mm (1/2 in.) overlaps. Lap shear samples prepared using this adhesive and composite adherends based on graphite/NR-150B2 were shown to have a high degree of resistance to such adverse environments as air at 589K (600 F), high humidity, methyl ethyl ketone and jet fuel. Bond line toughness was illustrated by the complete resistance to cracking in the wedge-crack propagation test. The available evidence indicates that wide area composite to composite or composite to metal bonding should be feasible.
Otis R. Walton
This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and\\/or tribo-electric charging) are likely to
Propulsion by directional adhesion
John Bush; Manu Prakash
The rough, hairy integument of water-walking arthropods is well known to be responsible for their water-repellency; we here consider its additional propulsive role. We demonstrate that the tilted flexible leg hairs of water-walking arthropods render the leg cuticle directionally anisotropic: contact lines advance most readily towards the leg tips. The dynamical role of the resulting unidirectional adhesion is explored, and
Adhesive bond degradation sensor
NASA Astrophysics Data System (ADS)
Wilson, Alan R.; Olsson-Jacques, Christina; Muscat, Richard F.
Early detection of adhesive bond degradation using sensing elements embedded within the 100um bond-line of aluminium epoxy adhesive joints has been demonstrated. Sensing elements of varying heights were fabricated at the ends of narrow conductors on a flexi-circuit carrier. This construction simulates the active sensing region on a patented silicon adhesive bond degradation sensor and has been used to characterize the sensing elements without the expense and time associated with fabricating the complete integrated silicon sensor. The highest elements on the flexi-circuit serve both as electrical pickup studs, providing a circuit from the flexi-circuit to the top aluminium plate, and as spacers to ensure that the shorter sensing elements do not contact the aluminium plate. The non-contacting sensing elements are thus arranged to be close to the metal/adhesive interface and are sensitive to any change in conductivity in this region due to release of ions as the interface is degraded by the environment. Accelerated aging tests were performed on flexi-circuit sensors embedded in the bond-line of double cantilever beam specimens. The specimens were immersed in 50░ C water and pre-loaded to just initiate a crack. Load on the specimen was then maintained by applying a constant load point displacement with a very low velocity to ensure that the environment would degrade the bond-line in advance of the crack front. The change of load and the conductivity measured by the sensing elements were then logged with time. The onset of bond degradation was detected approximately 10-20 mm ahead of the crack tip.
Candida albicans stimulates cytokine production and leukocyte adhesion molecule expression by endothelial cells.
Filler, S G; Pfunder, A S; Spellberg, B J; Spellberg, J P; Edwards, J E
Endothelial cells have the potential to influence significantly the host immune response to blood-borne microbial pathogens, such as Candida albicans. We investigated the ability (of this organism to stimulate endothelial cell responses relevant to host defense in vitro. Infection with C. albicans induced endothelial cells to express mRNAs encoding E-selectin, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, interleukin 6, interleukin 8, monocyte chemoattractant protein 1, and inducible cyclooxygenase (cox2). All three leukocyte adhesion molecule proteins were expressed on the surfaces of the endothelial cells after 8 h of exposure to C. albicans. An increase in secretion of all three cytokines was found after 12 h of infection. Cytochalasin D inhibited accumulation of the endothelial cell cytokine and leukocyte adhesion molecule mRNAs in response to C. albicans, suggesting that endothelial cell phagocytosis of the organism is required to induce this response. Live Candida tropicalis, Candida glabrata, a nongerminating strain of C. albicans, and killed C. albicans did not stimulate the expression of any of the cytokine or leukocyte adhesion molecule mRNAs. These findings indicate that a factor associated with live, germinating C. albicans is required for induction of endothelial cell mRNA expression. Furthermore, since endothelial cells phagocytize killed C. albicans, phagocytosis is likely necessary but not sufficient for this organism to stimulate mRNA accumulation. In conclusion, the secretion of proinflammatory cytokines and expression of leukocyte adhesion molecules by endothelial cells in response to C. albicans could enhance the host defense against this organism by contributing to the recruitment of activated leukocytes to sites of intravascular infection. PMID:8698486
Sharon, E; Lipovezky-Adler, M; Haramaty, O; Smidt, A
One of the reasons for immediate or late failure of restorations is the detachment of the restoration from the tooth. Retention for the restoration could be achieved from axial walls (macromechanical retention) or from adhesion of the restoration to the remaining tooth structure. Adhesion relies on bonding of resin cement to enamel or dentin on one side and to the restorative material on the other side. Bonding to enamel is predictable. Good bonding to dentin is more of a challenge especially with indirect restorations. In those cases the restoration is delivered usually a few days after the tooth was prepared during this time the exposed dentin might be contaminated or damaged. The question is whether you can rely on adhesion when cementing indirect restorations? In order to achieve the maximal bonding strength to dentin, the hybrid layer on the dentin must be built immediately after tooth preparation. This procedure is called Immediate Dentin Sealing. In vitro and clinical studies have shown better performance of restorations cemented following the IDS procedure. The article discusses the rational and the protocol of this procedure. A clinical case is presented as an example for the possibilities following this philosophy. PMID:24020243
IgG antiendothelial cell autoantibodies from scleroderma patients induce leukocyte adhesion to human vascular endothelial cells in vitro. Induction of adhesion molecule expression and involvement of endothelium-derived cytokines.
Carvalho, D; Savage, C O; Black, C M; Pearson, J D
IgG autoantibodies that bind human endothelial cells (AECA) were detected by ELISA in 30 of 42 samples of sera from patients with scleroderma. Pretreatment of human umbilical vein endothelial cells with AECA-positive scleroderma sera, or IgG purified from these sera, led to a dose- and time-dependent increase in the ability of the cells to bind human U937 monocytic cells. Threshold-active IgG concentrations were 1-10 micrograms/ml; effects were significant after 3 h and maximal after 6-12 h. IgG from AECA-negative sera or normal sera were without effect. Increased adhesion of U937 cells was accompanied by increased expression of endothelial intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin. Transfer of endothelial cell-conditioned media after pretreatment with AECA and immunodepletion of IgG demonstrated the presence of transferable activity that mimicked the effects of AECA. Treatment with neutralizing anticytokine antibodies indicated that IL-1, generated by the endothelial cells in response to AECA, was involved in the upregulation of adhesion molecules and U937 cell adhesion. We conclude that AECA can play a pathogenic role in scleroderma by activating endothelial cells, in part due to autocrine or paracrine actions of IL-1. PMID:8550821
Dietary flavonoid apigenin inhibits high glucose and tumor necrosis factor alpha-induced adhesion molecule expression in human endothelial cells.
Yamagata, Kazuo; Miyashita, Akinori; Matsufuji, Hiroshi; Chino, Makoto
Diabetes mellitus is associated with increased endothelial dysfunction and development of atherosclerotic vascular diseases. In contrast, an increased intake of dietary flavonoids is associated with a decreased risk of cardiovascular diseases. Here we demonstrate that high glucose (HG) and tumor necrosis factor alpha (TNFalpha) result in the expression of adhesion molecules and junctional molecules on endothelial cells (EC) within a short time. Simultaneously, we examined the regulatory effects of several dietary flavonoids. We demonstrated the short-term expression of adhesion molecules in a human EC line cultured with normal glucose (5.5 mM), HG (30 mM) and TNFalpha (10 ng/ml) by reverse transcription-polymerase chain reaction (RT-PCR), immunocytochemistry and adhesion assay. The expression of intercellular adhesion molecule-1 (ICAM1) and vascular cell adhesion molecule-1 (VCAM1) increased, but that of occludin decreased. Apigenin strongly inhibited the expression of VCAM1, IkappaB kinase (IKK) alpha and IKKepsilon/IKKi, and suppressed the adhesion of U937 cells. From the structure and inhibitory activity of several dietary flavonoids, it was recognized that a double bond between apigenin and the third hydroxyl group was required for inhibition of gene expression. HG and TNFalpha induced the expression of cell adhesion molecules and reduced that of occludin in EC. These flavonoids modified the expression of cloudin 5 and occludin. These results demonstrated that apigenin inhibits HG- and TNFalpha-induced adhesion molecule expression and that flavonoids regulate the expression of junctional molecules in human EC. It is suggested that apigenin inhibited the expression of several genes through inhibition of IKKs. PMID:19195861
Ginsenoside Rg3 inhibits tumor necrosis factor-alpha-induced expression of cell adhesion molecules in human endothelial cells.
Hien, Tran Thi; Kim, Nak Doo; Kim, Hyung Sik; Kang, Keon Wook
Ginsenoside Rg3 (Rg3), one of the most effective ginseng saponins, has anti-inflammatory and anti-cancer effects. This study examined the effects of Rg3 on cytokine-induced expression of adhesion molecules, which is a key early event in atherogenesis. Rg3 treatment inhibited tumor necrosis factor-alpha (TNF-alpha)-induced protein and mRNA expression of two cell adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) in ECV 304 human endothelial cells. In addition, expression of two pro-inflammatory cytokines, TNF-alpha and interleukin-1beta (IL-1beta), was suppressed by Rg3. Reporter gene analyses revealed that minimal reporter activities of nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) were blocked by Rg3 in a concentration-dependent manner. Taken together, these results indicate that Rg3 may have anti-inflammatory and anti-atherosclerotic activities in the vasculature, which is mediated partly by down-regulation of the expression of cell adhesion molecules and proinflammatory cytokines in endothelial cells. PMID:21038849
Peeling of Polydimethylsiloxane Adhesives : the Case of Adhesive Claude VERDIER(1) *,
Boyer, Edmond
Peeling of Polydimethylsiloxane Adhesives : the Case of Adhesive Failure Claude VERDIER(1 The adhesion properties of high molecular weight Polydimethylsiloxane adhesives are measured using 90░-peel effects. Recently, model polymers (Polydimethylsiloxanes, PDMS) were used10 to investigate the peeling
Reinforcement of surgical adhesive strips.
Mikhail, G R; Selak, L; Salo, S
Surgical adhesive strips are often used for closure of some wounds or to minimize tension on sutures after closures. The package insert of the type most commonly used (Steri-Strip), indicates that the application of compound tincture of benzoin, U.S.P. (CTB) increases strip adhesion. The increase in adhesive power by CTB was compared with a preparation containing gum mastic (Mastisol). The study clearly demonstrated that the latter preparation provided a markedly more adhesive strength than that obtained with CTB. PMID:3528256
3D Integration Using Adhesive, Metal, and Metal/Adhesive as Wafer Bonding Interfaces.
Salama, Khaled
3D Integration Using Adhesive, Metal, and Metal/Adhesive as Wafer Bonding Interfaces. Journal: 2008 Integration Using Adhesive, Metal, and Metal/Adhesive as Wafer Bonding Interfaces Jian-Qiang Lu1 , J. Jay Mc approaches to 3D integration using adhesive, metal, and metal/adhesive as the bonding interfaces
Effect of adhesive thickness on adhesively bonded T-joint
NASA Astrophysics Data System (ADS)
Abdullah, A. R.; Afendi, Mohd; Majid, M. S. Abdul
The aim of this work is to analyze the effect of adhesive thickness on tensile strength of adhesively bonded stainless steel T-joint. Specimens were made from SUS 304 Stainless Steel plate and SUS 304 Stainless Steel perforated plate. Four T-joint specimens with different adhesive thicknesses (0.5, 1.0, 1.5 and 2.0 mm) were made. Experiment result shows T-joint specimen with adhesive thickness of 1.0 mm yield highest maximum load. Identical T-joint specimen jointed by spot welding was also tested. Tensile test shows welded T-Joint had eight times higher tensile load than adhesively bonded T-joint. However, in low pressure application such as urea granulator chamber, high tensile strength is not mandatory. This work is useful for designer in fertilizer industry and others who are searching for alternative to spot welding.
Multiple Inflammatory Biomarker Detection in a Prospective Cohort Study: A Cross-Validation between Well-Established Single-Biomarker Techniques and an Electrochemiluminescense-Based Multi-Array Platform
van Bussel, Bas C. T.; Ferreira, Isabel; van de Waarenburg, Marjo P. H.; van Greevenbroek, Marleen M. J.; van der Kallen, Carla J. H.; Henry, Ronald M. A.; Feskens, Edith J. M.; Stehouwer, Coen D. A.; Schalkwijk, Casper G.
Background In terms of time, effort and quality, multiplex technology is an attractive alternative for well-established single-biomarker measurements in clinical studies. However, limited data comparing these methods are available. Methods We measured, in a large ongoing cohort study (n?=?574), by means of both a 4-plex multi-array biomarker assay developed by MesoScaleDiscovery (MSD) and single-biomarker techniques (ELISA or immunoturbidimetric assay), the following biomarkers of low-grade inflammation: C-reactive protein (CRP), serum amyloid A (SAA), soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1). These measures were realigned by weighted Deming regression and compared across a wide spectrum of subjectsÆ cardiovascular risk factors by ANOVA. Results Despite that both methods ranked individualsÆ levels of biomarkers very similarly (PearsonÆs r all?0.755) absolute concentrations of all biomarkers differed significantly between methods. Equations retrieved by the Deming regression enabled proper realignment of the data to overcome these differences, such that intra-class correlation coefficients were then 0.996 (CRP), 0.711 (SAA), 0.895 (sICAM-1) and 0.858 (sVCAM-1). Additionally, individual biomarkers differed across categories of glucose metabolism, weight, metabolic syndrome and smoking status to a similar extent by either method. Conclusions Multiple low-grade inflammatory biomarker data obtained by the 4-plex multi-array platform of MSD or by well-established single-biomarker methods are comparable after proper realignment of differences in absolute concentrations, and are equally associated with cardiovascular risk factors, regardless of such differences. Given its greater efficiency, the MSD platform is a potential tool for the quantification of multiple biomarkers of low-grade inflammation in large ongoing and future clinical studies. PMID:23472208
Electrically controlled DNA adhesion
NASA Astrophysics Data System (ADS)
Erdmann, Matthias; David, Ralf; Fornof, Ann; Gaub, Hermann E.
The ability to control the interaction of polyelectrolytes, such as DNA or proteins, with charged surfaces is of pivotal importance for a multitude of biotechnological applications. Previously, we measured the desorption forces of single polymers on charged surfaces using an atomic force microscope. Here, we show that the adhesion of DNA on gold electrodes modified with self-assembled monolayers can be biased by the composition of the monolayer and externally controlled by means of the electrode potential. Positive potentials induced DNA adsorption onto OH-terminated electrodes with adhesion forces up to 25 pN (at +0.5 V versus Ag/AgCl), whereas negative potentials suppressed DNA adsorption. The measured contributions of the DNA backbone phosphate charges and the doubly charged terminal phosphate on adsorption agreed with a model based on the Gouy-Chapman theory. Experiments on an NH2-terminated electrode revealed a similar force modulation range of the coulomb component of the desorption force. These findings are important for the development of new DNA-based biochips or supramolecular structures.
Effect of fibril shape on adhesive properties
NASA Astrophysics Data System (ADS)
Soto, Daniel; Hill, Ginel; Parness, Aaron; Esparza, Noķ; Cutkosky, Mark; Kenny, Tom
Research into the gecko's adhesive system revealed a unique architecture for adhesives using tiny hairs. By using a stiff material (?-keratin) to create a highly structured adhesive, the gecko's system demonstrates properties not seen in traditional pressure-sensitive adhesives which use a soft, unstructured planar layer. In contrast to pressure sensitive adhesives, the gecko adhesive displays frictional adhesion, in which increased shear force allows it to withstand higher normal loads. Synthetic fibrillar adhesives have been fabricated but not all demonstrate this frictional adhesion property. Here we report the dual-axis force testing of single silicone rubber pillars from synthetic adhesive arrays. We find that the shape of the adhesive pillar dictates whether frictional adhesion or pressure-sensitive behavior is observed. This work suggests that both types of behavior can be achieved with structures much larger than gecko terminal structures. It also indicates that subtle differences in the shape of these pillars can significantly influence their properties.
[Effects of rhG-CSF Stimulation in vitro on the Adhesion and Polarization of Human CD4?T Lymphocytes].
Zhao, Sha-Sha; Gu, Zhen-Yang; Li, Meng; Zhao, Xiao-Li; Luo, Lan; Guan, Li-Xun; Wang, Li-Li; Gao, Chun-Ji
The adhesion and polarization of T lymphocytes involved in the adhesive interaction of lymphocyte function-associated antigen 1 (LFA-1) with its ligand intercellular adhesion molecule 1 (ICAM-1). This study was aimed to investigate the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) stimulation in vitro on the adhesion and polarization of CD4? T cells of healthy human in peripheral blood. The peripheral blood mononuclear cells were collected from 12 healthy volunteers. The CD4? T cells were sorted by miniMACS. The sorted CD4? T cells were incubated with rhG-CSF for 24 h, then the adhesion and polarization of CD4? T cells activated by stroma cell-derived factor -1? (SDF-1?) and ICAM-1 were detected by ELISA and inverted microscope. The results showed that the percentage of adhesion CD4?T cells in the experimental group (rhG-CSF acting on the healthy adult volunteers) (61.9 ▒ 5.9)% was lower than that in the control group (healthy adult volunteers without rhG-CSF stimulation) (68.3 ▒ 7.3)% (P < 0.05). The percentage of polarized CD4?T cells in the experimental group (24.3 ▒ 4.3)% was also lower than that in control group (47.1 ▒ 5.1)% (P < 0.05). It is concluded that the adhesion and polarization of CD4?T lymphocytes can be inhibited after rhG-CSF stimulation. PMID:25543500
Chlorophyll-Related Compounds Inhibit Cell Adhesion and Inflammation in Human Aortic Cells
Lin, Kuan-Hung; Hsu, Ching-Yun; Huang, Ya-Ping; Lai, Jun-You; Hsieh, Wen-Bin; Huang, Meng-Yuan
Abstract The objectives of this study were to investigate the effects of chlorophyll-related compounds (CRCs) and chlorophyll (Chl) a+b on inflammation in human aortic endothelial cells. Adhesion molecule expression and interleukin (IL)-8, nuclear factor (NF)-?B p65 protein, and NF-?B and activator protein (AP)-1 DNA binding were assessed. The effects of CRCs on inflammatory signaling pathways of signal transducers and activators of transcription 3 (STAT3) and mothers against decapentaplegic homolog 4, respectively induced by IL-6 and transforming growth factor (TGF)-?, in human aortic smooth muscle cells cultured in vitro were also investigated. HAECs were pretreated with 10 ?M of CRCs, Chl a+b, and aspirin (Asp) for 18?h followed by tumor necrosis factor (TNF)-? (2?ng/mL) for 6?h, and U937 cell adhesion was determined. TNF-?¢induced monocyte-endothelial cell adhesion was significantly inhibited by CRCs. Moreover, CRCs and Chl a+b significantly attenuated vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and IL-8 expressions. Treatments also significantly decreased in NF-?B expression, DNA binding, and AP-1 DNA binding by CRCs and Asp. Thus, CRCs exert anti-inflammatory effects through modulation of NF-?B and AP-1 signaling. Ten micromoles of CRCs and Asp upregulated the expression of mothers against decapentaplegic homolog 4 (Drosophila) (SMAD4) in the TGF-? receptor signaling pathway, and SMAD3/4 transcription activity was also increased. Ten micromoles of CRCs were able to potently inhibit STAT3-binding activity by repressing IL-6¢induced STAT3 expression. Our results provide a potential mechanism that explains the anti-inflammatory activities of these CRCs. PMID:24066944
Regulation of adhesion molecules expression in TNF-?-stimulated brain microvascular endothelial cells by tanshinone IIA: involvement of NF-?B and ROS generation.
Tang, Chao; Xue, Hong-Li; Bai, Chang-Lin; Fu, Rong
Pro-inflammatory cytokine-mediated expression of cell surface adhesion molecules plays a key role in endothelial cell injury, leading to vascular inflammation and the development of many cerebrovascular diseases. Thus, antiinflammatory agents targeting these adhesion molecules may represent potential drugs for the prevention and treatment of cerebrovascular diseases. The present study explored the effects of tanshinone IIA (Tan IIA), an active ingredient present in the Salvia miltiorrhiza root, on the expression of cellular adhesion molecules in TNF-?-stimulated brain microvascular endothelial cells (BMVECs). Treatment with Tan IIA was found to suppress the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), resulting in inhibition of TNF-?-induced adhesion of neutrophils to BMVECs in a dose-dependent manner. In addition, Tan IIA significantly inhibited TNF-?-induced production of reactive oxygen species (ROS), which was accompanied by decreased malondialdehyde (MDA) levels. Treatment with Tan IIA also inhibited nuclear factor-kappa B (NF-?B) activation. Together, these results suggest that Tan IIA regulates TNF-?-induced expression of VCAM-1 and ICAM-1 through inhibition of NF-?B activation and ROS generation in BMVECs. PMID:20687137
Inhibition of tumor necrosis factor-{alpha}-induced expression of adhesion molecules in human endothelial cells by the saponins derived from roots of Platycodon grandiflorum
Kim, Ji Young [Department of Pharmacy, College of Pharmacy, Research Center for Proteineous Materials, Chosun University, Kwangju (Korea, Republic of); Kim, Dong Hee [Department of Pathology, College of Oriental Medicine, Daejeon University, Daejeon (Korea, Republic of); Kim, Hyung Gyun [Department of Pharmacy, College of Pharmacy, Research Center for Proteineous Materials, Chosun University, Kwangju (Korea, Republic of); Song, Gyu-Yong [Department of Pharmacy, College of Pharmacy, Chungnam National University, Taejon (Korea, Republic of); Chung, Young Chul [Division of Food Science, Chinju International University, Chinju (Korea, Republic of); Roh, Seong Hwan [Jangsaeng Doraji Research Institute of Biotechnology, Jangsaeng Doraji Co., Ltd., Chinju (Korea, Republic of); Jeong, Hye Gwang [Department of Pharmacy, College of Pharmacy, Research Center for Proteineous Materials, Chosun University, Kwangju (Korea, Republic of)]. E-mail: email@example.com
Adhesion molecules play an important role in the development of atherogenesis and are produced by endothelial cells after being stimulated with various inflammatory cytokines. This study examined the effect of saponins that were isolated from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil saponins (CKS), on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. CKS significantly inhibited the TNF{alpha}-induced increase in monocyte adhesion to endothelial cells as well as decreased the protein and mRNA expression levels of vascular adhesion molecule-1 and intercellular cell adhesion molecule-1 on endothelial cells. Furthermore, CKS significantly inhibited the TNF{alpha}-induced production of intracellular reactive oxygen species (ROS) and activation of NF-{kappa}B by preventing I{kappa}B degradation and inhibiting I{kappa}B kinase activity. Overall, CKS has anti-atherosclerotic and anti-inflammatory activity, which is least in part the result of it reducing the cytokine-induced endothelial adhesion to monocytes by inhibiting intracellular ROS production, NF-{kappa}B activation, and cell adhesion molecule expression in endothelial cells.
Fire-Retardant Epoxy Adhesives
NASA Technical Reports Server (NTRS)
Bilow, N.; Giants, T. W.
Phosphorus-containing epoxy is fire-retardant and translucent. Intended as adhesive for laminated plastic sheets, new material bonds well to titanium dioxide-filled plastic film, which ordinarily shows little surface interaction with adhesives. Fire retardancy has been demonstrated, and smoke density is low enough to avoid smoke obscuration.
Adhesive secretions in the platyhelminthes
Ian D. Whittington; Bronwen W. Cribb
This review is the first to draw together knowledge about bioadhesives secreted by a group of parasites. Mechanisms of mechanical attachment are well known among parasites, but some can also attach to host surfaces by chemical means using a thin layer of adhesive material secreted at the parasite-host interface. Attachment by adhesives to living surfaces has not been studied in
Bacterial Adhesion at Synthetic Surfaces
A systematic investigation into the effect of surface chemistry on bacterial adhesion was carried out. In particular, a number of physicochemical factors important in defining the surface at the molecular level were assessed for their effect on the adhesion of Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli. The primary experiments involved the grafting of groups varying in hydrophilicity,
Regulation of T-lymphocyte motility, adhesion and de-adhesion by a cell surface mechanism directed by low density lipoprotein receptor-related protein 1 and endogenous thrombospondin-1.
Talme, Toomas; Bergdahl, Eva; Sundqvist, Karl-G÷sta
T lymphocytes are highly motile and constantly reposition themselves between a free-floating vascular state, transient adhesion and migration in tissues. The regulation behind this unique dynamic behaviour remains unclear. Here we show that T cells have a cell surface mechanism for integrated regulation of motility and adhesion and that integrin ligands and CXCL12/SDF-1 influence motility and adhesion through this mechanism. Targeting cell surface-expressed low-density lipoprotein receptor-related protein 1 (LRP1) with an antibody, or blocking transport of LRP1 to the cell surface, perturbed the cell surface distribution of endogenous thrombospondin-1 (TSP-1) while inhibiting motility and potentiating cytoplasmic spreading on intercellular adhesion molecule 1 (ICAM-1) and fibronectin. Integrin ligands and CXCL12 stimulated motility and enhanced cell surface expression of LRP1, intact TSP-1 and a 130,000 MW TSP-1 fragment while preventing formation of a de-adhesion-coupled 110 000 MW TSP-1 fragment. The appearance of the 130 000 MW TSP-1 fragment was inhibited by the antibody that targeted LRP1 expression, inhibited motility and enhanced spreading. The TSP-1 binding site in the LRP1-associated protein, calreticulin, stimulated adhesion to ICAM-1 through intact TSP-1 and CD47. Shear flow enhanced cell surface expression of intact TSP-1. Hence, chemokines and integrin ligands up-regulate a dominant motogenic pathway through LRP1 and TSP-1 cleavage and activate an associated adhesion pathway through the LRP1-calreticulin complex, intact TSP-1 and CD47. This regulation of T-cell motility and adhesion makes pro-adhesive stimuli favour motile responses, which may explain why T cells prioritize movement before permanent adhesion. PMID:24877199
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Downregulation of Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 in Oral Squamous Cell Carcinoma: Correlation with Tumor Progression and Poor Prognosis
Keiji Shinozuka; Katsuhiro Uzawa; Kazuaki Fushimi; Yukio Yamano; Masashi Shiiba; Hiroki Bukawa; Hidetaka Yokoe; Hideki Tanzawa
Objective: To identify genes associated with therapeutic targets of oral squamous cell carcinoma (OSCC), we compared gene expression profiles in OSCC-derived cell lines with human normal oral keratinocytes. Methods: We analyzed the gene expression profiles of OSCCs using Affymetrix GeneChip analysis. The identified genes were analyzed by an Ingenuity Pathway Analysis tool to identify networks of interacting genes. A candidate
Absence of Platelet Endothelial Cell Adhesion Molecule 1, PECAM-1/CD31, In Vivo Increases Resistance to Salmonella enterica Serovar Typhimurium in Mice
Lovelace, Michael D.; Yap, May Lin; Yip, Jana; Muller, William; Wijburg, Odilia
PECAM-1/CD31 is known to regulate inflammatory responses and exhibit pro- and anti-inflammatory functions. This study was designed to determine the functional role of PECAM-1 in susceptibility to murine primary in vivo infection with Salmonella enterica serovar Typhimurium and in in vitro inflammatory responses of peritoneal macrophages. Lectin profiling showed that cellular PECAM-1 and recombinant human PECAM-1-Ig chimera contain high levels of mannose sugars and N-acetylglucosamine. Consistent with this carbohydrate pattern, both recombinant human and murine PECAM-1-Ig chimeras were shown to bind S. Typhimurium in a dose-dependent manner in vitro. Using oral and fecal-oral transmission models of S. Typhimurium SL1344 infection, PECAM-1?/? mice were found to be more resistant to S. Typhimurium infection than wild-type (WT) C57BL/6 mice. While fecal shedding of S. Typhimurium was comparable in wild-type and PECAM-1?/? mice, the PECAM-1-deficient mice had lower bacterial loads in systemic organs such as liver, spleen, and mesenteric lymph nodes than WT mice, suggesting that extraintestinal dissemination was reduced in the absence of PECAM-1. This reduced bacterial load correlated with reduced tumor necrosis factor (TNF), interleukin-6 (IL-6), and monocyte chemoattractant protein (MCP) levels in sera of PECAM-1?/? mice. Following in vitro stimulation of macrophages with either whole S. Typhimurium, lipopolysaccharide (LPS) (Toll-like receptor 4 [TLR4] ligand), or poly(IĘC) (TLR3 ligand), production of TNF and IL-6 by PECAM-1?/? macrophages was reduced. Together, these results suggest that PECAM-1 may have multiple functions in resistance to infection with S. Typhimurium, including binding to host cells, extraintestinal spread to deeper tissues, and regulation of inflammatory cytokine production by infected macrophages. PMID:23509149
Activation of Transcription Factor AP2 Mediates UVA Radiation and Singlet Oxygen-Induced Expression of the Human Intercellular Adhesion Molecule 1 Gene
Susanne Grether-Beck; Sylvia Olaizola-Horn; Heidi Schmitt; Markus Grewe; Andreas Jahnke; Judith P. Johnson; Karlis Briviba; Helmut Sies; Jean Krutmann
UVA radiation is the major component of the UV solar spectrum that reaches the earth, and the therapeutic application of UVA radiation is increasing in medicine. Analysis of the cellular effects of UVA radiation has revealed that exposure of human cells to UVA radiation at physiological doses leads to increased gene expression and that this UVA response is primarily mediated
Absence of platelet endothelial cell adhesion molecule 1, PECAM-1/CD31, in vivo increases resistance to Salmonella enterica serovar Typhimurium in mice.
Lovelace, Michael D; Yap, May Lin; Yip, Jana; Muller, William; Wijburg, Odilia; Jackson, Denise E
PECAM-1/CD31 is known to regulate inflammatory responses and exhibit pro- and anti-inflammatory functions. This study was designed to determine the functional role of PECAM-1 in susceptibility to murine primary in vivo infection with Salmonella enterica serovar Typhimurium and in in vitro inflammatory responses of peritoneal macrophages. Lectin profiling showed that cellular PECAM-1 and recombinant human PECAM-1-Ig chimera contain high levels of mannose sugars and N-acetylglucosamine. Consistent with this carbohydrate pattern, both recombinant human and murine PECAM-1-Ig chimeras were shown to bind S. Typhimurium in a dose-dependent manner in vitro. Using oral and fecal-oral transmission models of S. Typhimurium SL1344 infection, PECAM-1(-/-) mice were found to be more resistant to S. Typhimurium infection than wild-type (WT) C57BL/6 mice. While fecal shedding of S. Typhimurium was comparable in wild-type and PECAM-1(-/-) mice, the PECAM-1-deficient mice had lower bacterial loads in systemic organs such as liver, spleen, and mesenteric lymph nodes than WT mice, suggesting that extraintestinal dissemination was reduced in the absence of PECAM-1. This reduced bacterial load correlated with reduced tumor necrosis factor (TNF), interleukin-6 (IL-6), and monocyte chemoattractant protein (MCP) levels in sera of PECAM-1(-/-) mice. Following in vitro stimulation of macrophages with either whole S. Typhimurium, lipopolysaccharide (LPS) (Toll-like receptor 4 [TLR4] ligand), or poly(IĘC) (TLR3 ligand), production of TNF and IL-6 by PECAM-1(-/-) macrophages was reduced. Together, these results suggest that PECAM-1 may have multiple functions in resistance to infection with S. Typhimurium, including binding to host cells, extraintestinal spread to deeper tissues, and regulation of inflammatory cytokine production by infected macrophages. PMID:23509149
Transcriptional activation of the intercellular adhesion molecule 1 (CD54) gene by human T lymphotropic virus types I and II Tax is mediated through a palindromic response element.
Owen, S M; Rudolph, D L; Dezzutti, C S; Shibata, N; Naik, S; Caughman, S W; Lal, R B
In vitro infection of T cells with human T lymphotropic virus types I and II (HTLV-I and HTLV-II) resulted in constitutive expression of ICAM-1. Higher levels of ICAM-1 mRNA were expressed in HTLV-transformed cell lines (MT-2, MoT, C8166) when compared with uninfected T cell lines (A301). We demonstrate that this activation is conferred through a site on the ICAM-1 promoter that is activated in trans by the Tax protein of HTLV-I and HTLV-II. Enhanced promoter activity was detected when the ICAM-1 construct (-1162/+1) was transfected into HTLV-I-infected (MT-2), HTLV-II-infected (MoT, AI 1050), or an HTLV-I Tax-only-expressing (C8166) cell line as compared to the uninfected T cell line (A3.01). Cotransfection of the uninfected T cell line A3.01 with the ICAM construct along with Tax-I and Tax-II expression plasmid also resulted in increased promoter activity. Furthermore, experiments with deletion constructs of the ICAM-1 promoter region indicated that a region between -88 and -53 bp relative to the transcription start site is sufficient for Tax-inducible CAT expression. This segment includes an 11-bp palindromic segment (TTTCCGGGAAA) that has homology with the IFN-gamma and IL-6 response element. An 11-bp segment containing this regulatory region proved to be sufficient to confer Tax-I and Tax-II inducibility on a heterologous promoter (TK-CAT). Taken together these findings indicate that constitutive expression of ICAM-1 by HTLV-infected cells is influenced by the viral trans-activator protein Tax. This increased expression of ICAM-1 in response to the Tax protein may play an important role in the lymphoproliferation associated with HTLV infection. PMID:9359663
Structural specializations of ?4?7, an integrin that mediates rolling adhesion
Yu, Yamei; Zhu, Jianghai; Mi, Li-Zhi; Walz, Thomas; Sun, Hao; Chen, JianFeng
The lymphocyte homing receptor integrin ?4?7 is unusual for its ability to mediate both rolling and firm adhesion. ?4?1 and ?4?7 are targeted by therapeutics approved for multiple sclerosis and CrohnÆs disease. Here, we show by electron microscopy and crystallography how two therapeutic Fabs, a small molecule (RO0505376), and mucosal adhesion molecule-1 (MAdCAM-1) bind ?4?7. A long binding groove at the ?4¢?7 interface for immunoglobulin superfamily domains differs in shape from integrin pockets that bind Arg-Gly-Asp motifs. RO0505376 mimics an Ile/Leu-Asp motif in ?4 ligands, and orients differently from Arg-Gly-Asp mimics. A novel auxiliary residue at the metal ion¢dependent adhesion site in ?4?7 is essential for binding to MAdCAM-1 in Mg2+ yet swings away when RO0505376 binds. A novel intermediate conformation of the ?4?7 headpiece binds MAdCAM-1 and supports rolling adhesion. Lack of induction of the open headpiece conformation by ligand binding enables rolling adhesion to persist until integrin activation is signaled. PMID:22232704
Wet Adhesion and Adhesive Locomotion of Snails on Anti-Adhesive Non-Wetting Surfaces
Shirtcliffe, Neil J.; McHale, Glen; Newton, Michael I.
Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces. PMID:22693563
Wet adhesion and adhesive locomotion of snails on anti-adhesive non-wetting surfaces.
Shirtcliffe, Neil J; McHale, Glen; Newton, Michael I
Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces. PMID:22693563
Serial analysis of serum and ascitic fluid levels of soluble adhesion molecules and chemokines in patients with spontaneous bacterial peritonitis
Gir¾n-Gonzßlez, J A; RodrĒguez-Ramos, C; Elvira, J; Galßn, F; Del ┴lamo, C F-G; DĒaz, F; MartĒn-Herrera, L
The aim of this work was the evaluation of serum and ascitic fluid levels of chemokines (IL-8, growth-regulated oncogene (Gro-?), and monocyte chemotactic protein-1 (MCP-1)), and of soluble adhesion molecules (P-selectin, E-selectin, l-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)) in patients with spontaneous bacterial peritonitis (SBP). These compounds were serially analysed in serum and ascitic fluid by ELISA in patients with SBP (n = 20), non-infected cirrhotic controls (n = 12), and healthy controls (n = 15). Infected and non-infected cirrhotic patients showed significantly higher serum levels of adhesion molecules. SBP was associated with significantly higher serum and ascitic fluid levels of IL-8, Gro-? and ICAM-1 and with ascitic fluid concentrations of MCP-1. Significantly elevated serum levels of both ICAM-1 and VCAM-1 were detected in patient non-survivors after SBP. Thus, higher ascitic fluid levels of chemokines could be implicated in the peritoneal infiltrate in patients with SBP. Prognostic significance can be attributed to serum levels of ICAM-1 and VCAM-1 in these patients. PMID:11167998
Chronic epithelial kidney injury molecule-1 expression causes murine kidney fibrosis
Humphreys, Benjamin D.; Xu, Fengfeng; Sabbisetti, Venkata; Grgic, Ivica; Naini, Said Movahedi; Wang, Ningning; Chen, Guochun; Xiao, Sheng; Patel, Dhruti; Henderson, Joel M.; Ichimura, Takaharu; Mou, Shan; Soeung, Savuth; McMahon, Andrew P.; Kuchroo, Vijay K.; Bonventre, Joseph V.
Acute kidney injury predisposes patients to the development of both chronic kidney disease and end-stage renal failure, but the molecular details underlying this important clinical association remain obscure. We report that kidney injury molecule-1 (KIM-1), an epithelial phosphatidylserine receptor expressed transiently after acute injury and chronically in fibrotic renal disease, promotes kidney fibrosis. Conditional expression of KIM-1 in renal epithelial cells (Kim1RECtg) in the absence of an injury stimulus resulted in focal epithelial vacuolization at birth, but otherwise normal tubule histology and kidney function. By 4 weeks of age, Kim1RECtg mice developed spontaneous and progressive interstitial kidney inflammation with fibrosis, leading to renal failure with anemia, proteinuria, hyperphosphatemia, hypertension, cardiac hypertrophy, and death, analogous to progressive kidney disease in humans. Kim1RECtg kidneys had elevated expression of proinflammatory monocyte chemotactic protein-1 (MCP-1) at early time points. Heterologous expression of KIM-1 in an immortalized proximal tubule cell line triggered MCP-1 secretion and increased MCP-1¢dependent macrophage chemotaxis. In mice expressing a mutant, truncated KIM-1 polypeptide, experimental kidney fibrosis was ameliorated with reduced levels of MCP-1, consistent with a profibrotic role for native KIM-1. Thus, sustained KIM-1 expression promotes kidney fibrosis and provides a link between acute and recurrent injury with progressive chronic kidney disease. PMID:23979159
Kidney injury molecule-1 is involved in the chemotactic migration of mesenchymal stem cells.
Park, Kyung-Mee; Nam, Hyun-Suk; Teotia, Pankaj Kumar; Hussein, Kamal Hany; Hong, Seok-Ho; Yun, Jung-Im; Woo, Heung-Myong
A better understanding of the organ specific factors that regulate the migration of mesenchymal stem cells (MSCs) into the target organ is essential for optimization of strategies to improve the repair after injury. In the present study, we showed that the kidney injury molecule-1 (KIM-1), a well-known kidney-specific biomarker, enhanced the in vitro migration capacity of MSCs as a potent kidney-specific chemo-attractant or an inducer. The in vitro roles were verified by migration assay using KIM1-PK1 cell lines, the mouse proximal tubular epithelial cells (mPTEs) and recombinant human KIM-1 proteins (rhKIM-1). Immunofluorescence staining displayed specific ectodomain binding of KIM-1 on the surface of MSCs. Upregulation of chemokine receptor type 4 (CXCR4) protein when treated with tumor necrosis factor alpha (TNF-?) was shown. The effect of KIM-1 on migration of MSCs was augmented by TNF-? pretreatment in a dose-dependent manner, and reduced by AMD3100, an antagonist of CXCR4. These results suggest that KIM-1 is a potential chemo-ligand of CXCR4 and may play an important role in kidney-specific migration of MSCs via interaction between KIM-1 and CXCR4. PMID:24652046
Kidney injury molecule-1 is a phosphatidylserine receptor that confers a phagocytic phenotype on epithelial cells.
Ichimura, Takaharu; Asseldonk, Edwin J P V; Humphreys, Benjamin D; Gunaratnam, Lakshman; Duffield, Jeremy S; Bonventre, Joseph V
Following injury, the clearance of apoptotic and necrotic cells is necessary for mitigation and resolution of inflammation and tissue repair. In addition to macrophages, which are traditionally assigned to this task, neighboring epithelial cells in the affected tissue are postulated to contribute to this process. Kidney injury molecule-1 (KIM-1 or TIM-1) is an immunoglobulin superfamily cell-surface protein not expressed by cells of the myeloid lineage but highly upregulated on the surface of injured kidney epithelial cells. Here we demonstrate that injured kidney epithelial cells assumed attributes of endogenous phagocytes. Confocal images confirm internalization of apoptotic bodies within KIM-1-expressing epithelial cells after injury in rat kidney tubules in vivo. KIM-1 was directly responsible for phagocytosis in cultured primary rat tubule epithelial cells and also porcine and canine epithelial cell lines. KIM-1 was able to specifically recognize apoptotic cell surface-specific epitopes phosphatidylserine, and oxidized lipoproteins, expressed by apoptotic tubular epithelial cells. Thus, KIM-1 is the first nonmyeloid phosphatidylserine receptor identified to our knowledge that transforms epithelial cells into semiprofessional phagocytes. PMID:18414680
Adhesively-bonded joints and repairs in metallic alloys, polymers and composite materials: Adhesives, adhesion theories and surface pretreatment
A. Baldan
In the present paper, the following topics are reviewed in detail: (a) the available adhesives, as well as their recent advances, (b) thermodynamic factors affecting the surface pretreatments including adhesion theories, wettability, surface energy, (c) bonding mechanisms in the adhesive joints, (d) surface pretreatment methods for the adhesively bonded joints, and as well as their recent advances, and (e) combined
Focal Adhesion Kinases in Adhesion Structures and Disease
Eleniste, Pierre P.; Bruzzaniti, Angela
Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421
Adhesive Bonding of Wood Materials
Charles B. Vick
ContentsAdhesion to Wood 9--1Surface Properties of Wood Adherends 9--2Extractives on Surfaces 9--3Knife- and Abrasive-Planed Surfaces 9--3Veneer Surfaces 9--4Surfaces of Wood and Nonwood Composite Products 9--5Physical Properties of Wood Adherends 9--6Density and Porosity 9--6Moisture Content and Dimensional Changes 9--7Adhesives 9--9Composition 9--9Health and Safety 9--10Strength and Durability 9--10Adhesive Selection 9--12Bonding Process 9--15Moisture Content Control 9--15...
Adhesive Exocrine Glands in Insects: Morphology, Ultrastructure, and Adhesive Secretion
Oliver Betz
\\u000a A literature survey is provided summarizing the available information on exocrine epidermal glands that produce adhesive secretions\\u000a in insects. The focus is on both the ultrastructure of the gland cells and the identity and function of the chemical secretion\\u000a produced by them. Insects employ adhesives for various functions such as tarsal attachment during locomotion, resisting external\\u000a detachment forces, mating, phoresy
Perflubron attenuates neutrophil adhesion to activated endothelial cells in vitro.
Woods, C M; Neslund, G; Kornbrust, E; Flaim, S F
Infiltration of activated neutrophils into the lung appears to be a key element in the severe lung injury that develops in animal models of acute lung injury. Partial liquid ventilation with perflubron has been shown to ameliorate tissue damage compared with conventional mechanical ventilation in acute lung injury models. Pilot experiments indicated that indirect exposure to perflubron could modulate the degree to which subsequent neutrophil binding to endothelial cell monolayers was upregulated after lipopolysaccharide activation. Endothelial cell monolayers preexposed to perflubron showed >40% reductions in the surface steady-state levels of E-selectin and intercellular adhesion molecule-1 achieved after proinflammatory activation (P < 0.05), which correlated with a reduction in the real-time association constants measured by biosensor techniques. These results indicate that direct contact with the perflubron liquid phase is not necessary to attenuate inflammatory responses. Rather, diffusion of perflubron from the alveolar space into the adjacent pulmonary vascular endothelial layer may modulate neutrophil adhesion and thereby reduce the rate of infiltration of activated neutrophils into the injured lung. PMID:10781432
Adhesion of liquid droplets to rough surfaces
Ri Li; Azar Alizadeh; Wen Shang
We study the adhesion of liquid droplets to rough surfaces, focusing on how adhesion changes with surface chemistry and roughness. For hydrophobic surfaces (equilibrium contact angle thetae>90░ ), although increasing surface roughness augments apparent contact angle, it does not necessarily always reduce adhesion. In a domain defined by roughness and equilibrium contact angle, this study identifies regions where adhesion increases
G. Klein
The bonding of wood by means of glue has been practised for many centuries.Adhesion between an adhesive and wood is the result of unbalanced secondary valency forces (Van der Waal's forces) present on the interfaces. It is fundamental to good adhesion that the adhesive must (a) wet the surface it is required to adhere to and (b) penetrate the wood
Failure Modes in Adhesively Bonded Carton Boards
Christer Korin; Nils Hallbõck; Robert Junghans
Carton board packages are often adhesively bonded. The adhesive joint may fail due to cohesive fracture in the adhesive, interfacial fracture between the adhesive and one of the carton board surfaces, or cohesive fracture in the carton board. The failure may also be a combination of these failure modes. From previous studies, it is well known that the failure mechanism
APPLIED PHYSICS REVIEWSFOCUSED REVIEW Adhesive wafer bonding
Salama, Khaled
APPLIED PHYSICS REVIEWSŁFOCUSED REVIEW Adhesive wafer bonding F. Niklausa Microsystem Technology 9 February 2006 Wafer bonding with intermediate polymer adhesives is an important fabrication-dimensional integrated circuits, advanced packaging, and microfluidics. In adhesive wafer bonding, the polymer adhesive
Depletion-induced Oligomerization of Stromal Interaction Molecule 1 (STIM1) via the EF-SAM Region
Ikura, Mitsuhiko
). The molecular mecha- nisms initiating ER STIM1 redistribution and plasma mem- brane CRAC activity are not well initiating STIM1 punctae formation via large conformational changes. The low Ca2 affinity of EFStored Ca2 Depletion-induced Oligomerization of Stromal Interaction Molecule 1 (STIM1) via the EF
Course 7: Cell Adhesion as Wetting Transition?
NASA Astrophysics Data System (ADS)
Sackmann, E.; Bruinsma, R.
1 Introduction 2 Mimicking cell adhesion 3 Microinterferometry: A versatile tool to evaluate adhesion strength and forces 4 Soft shell adhesion is controlled by a double well interfacial potential 5 How is adhesion controlled by membrane elasticity? 6 Measurement of adhesion strength by interferometric contour analysis 7 Switching on specific forces: Adhesion as localized dewetting process 8 Measurement of unbinding forces, receptor-ligand leverage and a new role for stress fibers 9 An application: Modification of cellular adhesion strength by cytoskeletal mutations 10 Conclusions A Appendix: Generic interfacial forces
Seafood delicacy makes great adhesive
Idaho National Laboratory - Frank Roberto, Heather Silverman
Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod
Investigation of organic adhesives for hybrid microcircuits
NASA Technical Reports Server (NTRS)
Perkins, K. L.; Licari, J. J.
The properties of organic adhesives were investigated to acquire information for a guideline document regarding the selection of adhesives for use in high reliability hybrid microcircuits. Specifically, investigations were made of (1) alternate methods for determining the outgassing of cured adhesives, (2) effects of long term aging at 150 C on the electrical properties of conductive adhesives, (3) effects of shelf life age on adhesive characteristics, (4) bond strengths of electrically conductive adhesives on thick film gold metallization, (5) a copper filled adhesive, (6) effects of products outgassed from cured adhesives on device electrical parameters, (7) metal migration from electrically conductive adhesives, and (8) ionic content of electrically insulative adhesives. The tests performed during these investigations are described, and the results obtained are discussed.
The direction of migration of T-lymphocytes under flow depends upon which adhesion receptors are engaged.
Dominguez, George A; Anderson, Nicholas R; Hammer, Daniel A
T-lymphocyte migration is important for homing, cell trafficking, and immune surveillance. T-lymphocytes express lymphocyte function-associated antigen-1 (LFA-1; ?L?2) and very late antigen-4 (VLA-4; ?4?1), which bind to their cognate ligands, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). These adhesive interactions provide T-lymphocytes with the ability to withstand hemodynamic shear forces to facilitate adhesion and migration along the blood endothelium. Recently, it has been shown that T-lymphocytes will crawl upstream against the direction of flow on surfaces functionalized with ICAM-1. Here, we have investigated whether the identity of the receptor and the magnitude of its engagement affects the direction of T-lymphocyte migration under flow. We used microcontact printed ICAM-1 and VCAM-1 PDMS surfaces on which density and type of adhesion molecule can be tightly controlled and non-specific adhesion adequately blocked. Using a laminar flow chamber, we demonstrate that T-lymphocytes migrate either upstream or downstream dependent upon ligand type, ligand concentration and shear rate. T-lymphocytes were found to migrate upstream on ICAM-1 but downstream on VCAM-1 surfaces - a behavior unique to T-lymphocytes. By varying concentrations of ICAM-1 and VCAM-1, directed migration under flow was observed to be dependent upon the type and concentration of ligand. As shear rates increase, T-lymphocytes favor upstream migration when any ICAM-1 is present, even in the presence of substantial amounts of VCAM-1. Furthermore, a loss of cytoskeletal polarity was observed upon introduction of fluid flow with reorganization that is dependent upon ligand presentation. These results indicate that T-lymphocytes exhibit two different modes of motility - upstream or downstream - under fluid flow that depends on ligand composition and the shear rate. PMID:25674729
NAD(P)H:quinone Oxidoreductase 1-Compromised Human Bone Marrow Endothelial Cells Exhibit Decreased Adhesion Molecule Expression and CD34+ Hematopoietic Cell Adhesion
Zhou, Hongfei; Dehn, Donna; Kepa, Jadwiga K.; Siegel, David; Scott, Devon E.; Tan, Wei
NAD(P)H:quinone oxidoreductase 1 (NQO1) deficiency resulting from a homozygous NQO1*2 polymorphism has been associated with an increased risk of benzene-induced myeloid toxicity and a variety of de novo and therapy-induced leukemias. Endothelial cells in human bone marrow form one of the two known hematopoietic stem cell microenvironments and are one of the major cell types that express NQO1 in bone marrow. We have used a transformed human bone marrow endothelial cell (TrHBMEC) line to study the potential impact of a lack of NQO1 activity on adhesion molecule [endothelial leukocyte adhesion molecule 1 (E-selectin), vascular cell adhesion molecule (VCAM)-1, and intercellular adhesion molecule (ICAM)-1] expression and functional adhesion to bone marrow progenitor cells. We used both 5-methoxy-1,2-dimethyl-3-[(4-nitrophenoxy)methyl]indole-4,7-dione (ES936), a mechanism-based inhibitor of NQO1, and anti-NQO1 small interfering RNA to abrogate NQO1 activity. Real-time reverse transcription-polymerase chain reaction data demonstrated a significant inhibition of tumor necrosis factor (TNF)?-induced E-selectin mRNA levels after ES936 pretreatment. Immunoblot assays demonstrated a significant reduction in TNF?-stimulated E-selectin, VCAM-1, and ICAM-1 proteins after inhibition or knockdown of NQO1. The mechanisms underlying this effect remain undefined, but modulation of nuclear factor-?B (p65), c-Jun, and activating transcription factor 2, transcriptional regulators of adhesion molecules, were observed after inhibition or knockdown of NQO1. Decreased level of E-selectin, VCAM-1, and ICAM-1 also resulted in a functional deficit in adhesion. A parallel plate flow chamber study demonstrated a marked reduction in CD34+ cell (KG1a) adhesion to NQO1-deficient TrHBMECs relative to controls. The reduced adhesive ability of TrHBMECs may affect the function of the vascular stem cell niche and also may contribute to the increased susceptibility of polymorphic individuals lacking NQO1 to leukemias and hematotoxicants such as benzene. PMID:20378716
Adhesion in organic electronic structures
T. Tong; B. Babatope; S. Admassie; J. Meng; O. Akwogu; W. Akande; W. O. Soboyejo
This paper presents the results of atomic force microscopy (AFM) measurements of the adhesion between materials relevant to organic solar cells and organic light-emitting devices. The adhesion is quantified using pull-off forces obtained for organic-organic, organic-inorganic, and inorganic-inorganic interfaces. The measured pull-off forces and surface parameters are then incorporated into theoretical models for the estimation of surface energies. The implications
The selectins: vascular adhesion molecules
The selectin family of adhesion mole- cules mediates the initial attachment of leukocytes to venular endothelial cells before their firm adhesion and diapedesis at sites of tissue injury and inflamma- tion. The selectin family consists of three closely related cell-surface molecules with differential ex- pression by leukocytes (L-selectin), platelets (P-se- lectin), and vascular endothelium (E- and P-selectin). The selectins have
LFA-1¢mediated Adhesion Is Regulated by Cytoskeletal Restraint and by a Ca2+-dependent Protease, Calpain
Stewart, Mairi P.; McDowall, Alison; Hogg, Nancy
The activity of integrins on leukocytes is kept under tight control to avoid inappropriate adhesion while these cells are circulating in blood or migrating through tissues. Using lymphocyte function-associated antigen-1 (LFA-1) on T cells as a model, we have investigated adhesion to ligand intercellular adhesion molecule-1 induced by the Ca2+ mobilizers, ionomycin, 2,5-di-t-butylhydroquinone, and thapsigargin, and the well studied stimulators such as phorbol ester and cross-linking of the antigen-specific T cell receptor (TCR)¢ CD3 complex. We report here that after exposure of T cells to these agonists, integrin is released from cytoskeletal control by the Ca2+-induced activation of a calpain-like enzyme, and adhesive contact between cells is strengthened by means of the clustering of mobilized LFA-1 on the membrane. We propose that methods of leukocyte stimulation that cause Ca2+ fluxes induce LFA-1 adhesion by regulation of calpain activity. These findings suggest a mechanism whereby engagement of the TCR could promote adhesion strengthening at an early stage of interaction with an antigen-presenting cell. PMID:9456328
Effects of nitric oxide-releasing nonsteroidal anti-inflammatory drugs (NONO-NSAIDs) on melanoma cell adhesion
Cheng, Huiwen [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States) [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States); Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701 (United States); Mollica, Molly Y.; Lee, Shin Hee [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States)] [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States); Wang, Lei [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States) [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States); Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701 (United States); Velßzquez-MartĒnez, Carlos A., E-mail: email@example.com [Chemistry Section, Laboratory of Comparative Carcinogenesis and Basic Research Program, SAIC-Frederick Inc., National Cancer Institute at Frederick, Frederick, MD 21702 (United States); Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton Alberta, Canada T6G 2N8 (Canada); Wu, Shiyong, E-mail: firstname.lastname@example.com [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States) [Edison Biotechnology Institute, Ohio University, Athens, OH 45701 (United States); Department of Chemistry and Biochemistry, Ohio University, Athens, OH 45701 (United States)
A new class of nitric oxide (NOĢ)-releasing nonsteroidal anti-inflammatory drugs (NONO-NSAIDs) were developed in recent years and have shown promising potential as NSAID substitutes due to their gentle nature on cardiovascular and gastrointestinal systems. Since nitric oxide plays a role in regulation of cell adhesion, we assessed the potential use of NONO-NSAIDs as anti-metastasis drugs. In this regard, we compared the effects of NONO-aspirin and a novel NONO-naproxen to those exerted by their respective parent NSAIDs on avidities of human melanoma M624 cells. Both NONO-NSAIDs, but not the corresponding parent NSAIDs, reduced M624 adhesion on vascular cellular adhesion molecule-1 (VCAM-1) by 20¢30% and fibronectin by 25¢44% under fluid flow conditions and static conditions, respectively. Only NONO-naproxen reduced (? 56%) the activity of ?1 integrin, which binds to ?4 integrin to form very late antigen-4 (VLA-4), the ligand of VCAM-1. These results indicate that the diazeniumdiolate (NOĢ)-donor moiety is critical for reducing the adhesion between VLA-4 and its ligands, while the NSAID moiety can impact the regulation mechanism of melanoma cell adhesion. -- Highlights: ? NONO-naproxen, a novel nitric oxide-releasing NSAID, was synthesized. ? NONO-NSAIDs, but not their parent NSAIDs, reduced melanoma adhesion. ? NONO-naproxen, but not NONO-aspirin and NSAIDs, reduced activity of ?1 integrin.
Fibrillar Adhesive for Climbing Robots
NASA Technical Reports Server (NTRS)
Pamess, Aaron; White, Victor E.
A climbing robot needs to use its adhesive patches over and over again as it scales a slope. Replacing the adhesive at each step is generally impractical. If the adhesive or attachment mechanism cannot be used repeatedly, then the robot must carry an extra load of this adhesive to apply a fresh layer with each move. Common failure modes include tearing, contamination by dirt, plastic deformation of fibers, and damage from loading/ unloading. A gecko-like fibrillar adhesive has been developed that has been shown useful for climbing robots, and may later prove useful for grasping, anchoring, and medical applications. The material consists of a hierarchical fibrillar structure that currently contains two levels, but may be extended to three or four levels in continuing work. The contacting level has tens of thousands of microscopic fibers made from a rubberlike material that bend over and create intimate contact with a surface to achieve maximum van der Waals forces. By maximizing the real area of contact that these fibers make and minimizing the bending energy necessary to achieve that contact, the net amount of adhesion has been improved dramatically.
Ginsenoside rg2 inhibits lipopolysaccharide-induced adhesion molecule expression in human umbilical vein endothelial cell.
Cho, Young-Suk; Kim, Chan Hyung; Ha, Tae-Sun; Lee, Sang Jin; Ahn, Hee Yul
Vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), P- and E-selectin play a pivotal role for initiation of atherosclerosis. Ginsenoside, a class of steroid glycosides, is abundant in Panax ginseng root, which has been used for prevention of illness in Korea. In this study, we investigated the mechanism(s) by which ginsenoside Rg2 may inhibit VCAM-1 and ICAM-1 expressions stimulated with lipopolysaccharide (LPS) in human umbilical vein endothelial cell (HUVEC). LPS increased VCAM-1 and ICAM-1 expression. Ginsenoside Rg2 prevented LPS-mediated increase of VCAM-1 and ICAM-1 expression. On the other hand, JSH, a nuclear factor kappa B (NF-?B) inhibitor, reduced both VCAM-1 and ICAM-1 expression stimulated with LPS. SB202190, inhibitor of p38 mitogen-activated protein kinase (p38 MAPK), and wortmannin, phosphatidylinositol 3-kinase (PI3-kinase) inhibitor, reduced LPS-mediated VCAM-1 but not ICAM-1 expression. PD98059, inhibitor of mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (MEK/ERK) did not affect VCAM-1 and ICAM-1 expression stimulated with LPS. SP600125, inhibitor of c-Jun N-terminal kinase (JNK), reduced LPS-mediated ICAM-1 but not VCAM-1 expression. LPS reduced IkappaB? (I?B?) expression, in a time-dependent manner within 1 hr. Ginsenoside Rg2 prevented the decrease of I?B? expression stimulated with LPS. Moreover, ginsenoside Rg2 reduced LPS-mediated THP-1 monocyte adhesion to HUVEC, in a concentration-dependent manner. These data provide a novel mechanism where the ginsenoside Rg2 may provide direct vascular benefits with inhibition of leukocyte adhesion into vascular wall thereby providing protection against vascular inflammatory disease. PMID:23626475
Insulin and Insulin-Like Growth Factor-I Receptors Differentially Mediate Insulin-Stimulated Adhesion Molecule Production by Endothelial Cells
Li, Guolian; Barrett, Eugene J.; Ko, Seung-Hyun; Cao, Wenhong; Liu, Zhenqi
Patients with type 2 diabetes are hyperinsulinemic and insulin resistant and develop premature atherosclerosis. High concentrations of insulin stimulate the production of adhesion molecules by endothelial cells (ECs). ECs express abundant IGF-I receptors as well as insulin receptors. Whether IGF-I receptors contribute to insulin-induced endothelial production of adhesion molecules is unknown. Bovine aortic ECs (BAECs) were incubated with insulin (100 nm) for 24 h. The cellular content of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) was measured, and monocyte adhesion to ECs was quantified. Insulin increased both VCAM-1 (P < 0.001) and ICAM-1 (P < 0.0002) content, which was accompanied by an increased number of monocytes adherent to BAECs (P = 0.0001). Inhibition of either MAPK kinase-1 or p38 MAPK but not phosphatidylinositol 3-kinase abolished insulin-mediated production of adhesion molecules. Insulin receptor small interfering RNA knockdown abolished insulin-stimulated increases of ICAM-1 but not VCAM-1. Conversely, IGF-I receptor blockade with either a neutralizing antibody or specific small interfering RNA eliminated insulin-induced VCAM-1 but not ICAM-1 production. Blockade of signaling via either the insulin or IGF-I receptors decreased monocyte adherence to BAECs (P < 0.01 for each). We conclude that insulin and IGF-I receptors differentially mediate the production of adhesion molecules by ECs and monocyte adhesion onto the vascular endothelium in response to the hyperinsulinemic state. Dual-receptor activation may most effectively contribute to the pathogenesis of atherosclerotic disease in diabetes. PMID:19423756
Application of X-ray microanalysis to study of the expression of endothelial adhesion molecules on human umbilical vein endothelial cells in vitro.
Tomczok, J; Sliwa-Tomczok, W; Klein, C L; Bittinger, F; Kirkpatrick, C J
A semi-quantitative procedure is described, which allows the evaluation of expression levels of endothelial adhesion molecules on cultured human umbilical vein endothelial cells (HUVEC) using energy dispersive X-ray microanalysis (EDX). As a model two adhesion molecules, E-selection (CD62E; ELAM-1/endothelial leukocyte adhesion molecule-1) and ICAM-1 (intercellular adhesion molecule-1; CD54), were localized by the use of the silver-enhancement colloidal gold method after stimulation of HUVEC with endotoxin lipopolysaccharide (LPS), tumour necrosis factor (TNF) or a phorbol ester (PMA). The analysis was performed in a scanning electron microscope (SEM) at an accelerating voltage of 15 kV with scanned areas of 200 x 400 microns. The semi-quantitative data indicated that in LPS-treated groups both adhesion molecules were expressed at a significantly higher level than in all other groups (P < 0.01). In addition, after a 4 h treatment the expression levels of E-selectin in all groups were higher compared to ICAM-1. The experimental data from X-ray microanalysis were compared with data obtained from an enzyme-linked immunosorbent assay (ELISA) and similar values were found for both types of preparation. This microanalytical method is relatively simple and seems to be suitable for immunogold labelling studies on different types of endothelial cells in vitro. PMID:7532636
[Adhesive lumbar arachnoiditis].
Ribeiro, C; Reis, F C
Spinal arachnoiditis, an inflammatory process involving all three meningeal layers as well as the nerve roots, is a cause of persistent symptoms in 6% to 16% of postoperative patients. Although spinal surgery is the most common antecedent associated with arachnoiditis, multiple causes have been reported, including infection, intrathecal steroids or anesthetic agents, trauma, subarachnoid hemorrhage and ionic myelographic contrast material--both oil soluble and water soluble. In the past, oil-based intrathecal contrast agents (Pantopaque) were associated with arachnoiditis especially when this material was introduced into the thecal sac and mixed with blood. Arachnoiditis is apparently rarely idiopathic. The pathogenesis of spinal arachnoiditis is similar to the repair process of serous membranes, such as the peritoneum, with a negligible inflammatory cellular exudate and a prominent fibrinous exudate. Chronic adhesive arachnoiditis of the lower spine is a myelographic diagnosis. The myelographic findings of arachnoiditis were divided into two types by Jorgensen et al. In type 1, "the empty thecal sac" appearance, there is homogeneous filling of the thecal sac with either absence of or defects involving nerve root sleeve filling. In type 2 arachnoiditis, there are localized or diffuse filling defects within the contrast column. MRI has demonstrated a sensitivity of 92% and a specificity of 100% in the diagnosis of arachnoiditis. The appearance of arachnoiditis on MRI can be assigned to three main groups. The MRI findings in group I are a conglomeration of adherent roots positioned centrally in the thecal sac. Patients in group II show roots peripherally adherent to the meninges--the so called empty sac. MRI findings in group III are a soft tissue mass within the subarachnoid space. It corresponds to the type 2 categorization defined by Jorgensen et al, where as the MRI imaging types I and II correspond to the myelographic type 1. PMID:9542180
Inhibition of Monocyte Adhesion to Brain-Derived Endothelial Cells by Dual Functional RNA Chimeras
Hu, Jing; Xiao, Feng; Hao, Xin; Bai, Shuhua; Hao, Jiukuan
Because adhesion of leukocytes to endothelial cells is the first step of vascular-neuronal inflammation, inhibition of adhesion and recruitment of leukocytes to vascular endothelial cells will have a beneficial effect on neuroinflammatory diseases. In this study, we used the pRNA of bacteriophage phi29 DNA packaging motor to construct a novel RNA nanoparticle for specific targeting to transferrin receptor (TfR) on the murine brain-derived endothelial cells (bEND5) to deliver ICAM-1 siRNA. This RNA nanoparticle (FRS-NPs) contained a FB4 aptamer targeting to TfR and a siRNA moiety for silencing the intercellular adhesion molecule-1 (ICAM-1). Our data indicated that this RNA nanoparticle was delivered into murine brain-derived endothelial cells. Furthermore, the siRNA was released from the FRS-NPs in the cells and knocked down ICAM-1 expression in the TNF-?¢stimulated cells and in the cells under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. The functional end points of the study indicated that FRS-NPs significantly inhibited monocyte adhesion to the bEND5 cells induced by TNF-? and OGD/R. In conclusion, our approach using RNA nanotechnology for siRNA delivery could be potentially applied for inhibition of inflammation in ischemic stroke and other neuroinflammatory diseases, or diseases affecting endothelium of vasculature. PMID:25368913
High performance Cu adhesion coating
Lee, K.W.; Viehbeck, A. [IBM T.J. Watson Research Center, Yorktown Heights, NY (United States); Chen, W.R.; Ree, M. [IBM Microelectronics Division, Hopewell Junction, NY (United States)
Poly(arylene ether benzimidazole) (PAEBI) is a high performance thermoplastic polymer with imidazole functional groups forming the polymer backbone structure. It is proposed that upon coating PAEBI onto a copper surface the imidazole groups of PAEBI form a bond with or chelate to the copper surface resulting in strong adhesion between the copper and polymer. Adhesion of PAEBI to other polymers such as poly(biphenyl dianhydride-p-phenylene diamine) (BPDA-PDA) polyimide is also quite good and stable. The resulting locus of failure as studied by XPS and IR indicates that PAEBI gives strong cohesive adhesion to copper. Due to its good adhesion and mechanical properties, PAEBI can be used in fabricating thin film semiconductor packages such as multichip module dielectric (MCM-D) structures. In these applications, a thin PAEBI coating is applied directly to a wiring layer for enhancing adhesion to both the copper wiring and the polymer dielectric surface. In addition, a thin layer of PAEBI can also function as a protection layer for the copper wiring, eliminating the need for Cr or Ni barrier metallurgies and thus significantly reducing the number of process steps.
Nanoparticle adhesion on soft substrates
NASA Astrophysics Data System (ADS)
Cao, Zhen; Dobrynin, Andrey; Oyer, Andrew; Stevens, Mark
Using combination of the molecular dynamics simulations and theoretical calculations we study adhesion of spherical and cylindrical nanoparticles on soft substrates. The nanoparticle and substrate deformations are obtained as a function of the nanoparticle and substrate crosslinking density, nanoparticle size and substrate thickness, surface energy of nanoparticles and substrate, and work of adhesion. We have showed that the classical JKR model can be applied to describe nanoparticle adhesion when deformation of both substrate and nanoparticle are small. In this so-called JKR-regime the deformations of substrates and nanoparticles are determined by balancing the elastic energy of deformed objects and work of adhesion between nanoparticle and substrate. However, in the case of soft substrates and nanoparticles when both objects undergo large deformations their equilibrium shapes are determined by balancing the surface energy and work of adhesion (the so-called wetting regime). We present a simple scaling model describing crossover between JKR and wetting regimes. The model predictions are in a very good agreement with simulation results. NSF # DMR-1004576.
How acoustic cavitation can improve adhesion.
Holtmannsp÷tter, J; Wetzel, M; Czarnecki, J V; Gudladt, H-J
In general, ultrasound is commonly used at low power level for non-destructive testing (NDT) and detection of delaminations in adhesive bonded structures. The present paper instead presents an approach where power ultrasound is used to improve interface formation prior to the bonding process and to ensure the quality of adhesive bonds by using acoustic cavitation in the liquid adhesive. Results from high-speed videos, rheological and thermal measurements and destructive testing of adhesive bonds with contaminated surfaces are presented and discussed. Power ultrasound can be used in general to improve adhesion and significantly to improve contamination tolerance and robustness of adhesive bonding processes. PMID:22465677
Adhesive capsulitis: a case report
Kazemi, Mohsen
Adhesive capsulitis or frozen shoulder is an uncommon entity in athletes. However, it is a common cause of shoulder pain and disability in the general population. Although it is a self limiting ailment, its rather long, restrictive and painful course forces the affected person to seek treatment. Conservative management remains the mainstay treatment of adhesive capsulitis. This includes chiropractic manipulation of the shoulder, therapeutic modalities, mobilization, exercise, soft tissue therapy, nonsteroidal anti-inflammatory drugs, and steroid injections. Manipulation under anesthesia is advocated when the conservative treatment fails. A case of secondary adhesive capsulitis in a forty-seven-year-old female recreational squash player is presented to illustrate clinical presentation, diagnosis, radiographic assessment and conservative chiropractic management. The patientÆs shoulder range of motion was full and pain free with four months of conservative chiropractic care. ImagesFigure 1Figure 2Figure 3
A novel addition polyimide adhesive
NASA Technical Reports Server (NTRS)
St.clair, T. L.; Progar, D. J.
An addition polyimide adhesive, LARC 13, was developed which shows promise for bonding both titanium and composites for applications which require service temperatures in excess of 533 K. The LARC 13 is based on an oligomeric bis nadimide containing a meta linked aromatic diamine. The adhesive melts prior to polymerization due to its oligomeric nature, thereby allowing it to be processed at 344 kPa or less. Therefore, LARC 13 is ideal for the bonding of honeycomb sandwich structures. After melting, the resin thermosets during the cure of the nadic endcaps to a highly crosslinked system. Few volatiles are evolved, thus allowing large enclosed structures to be bonded. Preparation of the adhesive as well as bonding, aging, and testing of lap shear and honeycomb samples are discussed.
Liposome adhesion generates traction stress
NASA Astrophysics Data System (ADS)
Murrell, Michael P.; Voituriez, Raphaļl; Joanny, Jean-Franńois; Nassoy, Pierre; Sykes, Cķcile; Gardel, Margaret L.
Mechanical forces generated by cells modulate global shape changes required for essential life processes, such as polarization, division and spreading. Although the contribution of the cytoskeleton to cellular force generation is widely recognized, the role of the membrane is considered to be restricted to passively transmitting forces. Therefore, the mechanisms by which the membrane can directly contribute to cell tension are overlooked and poorly understood. To address this, we directly measure the stresses generated during liposome adhesion. We find that liposome spreading generates large traction stresses on compliant substrates. These stresses can be understood as the equilibration of internal, hydrostatic pressures generated by the enhanced membrane tension built up during adhesion. These results underscore the role of membranes in the generation of mechanical stresses on cellular length scales and that the modulation of hydrostatic pressure due to membrane tension and adhesion can be channelled to perform mechanical work on the environment.
Adhesion of Activated Platelets to Endothelial Cells: Evidence for a GPIIbIIIa-dependent Bridging Mechanism and Novel Roles for Endothelial Intercellular Adhesion Molecule 1 (ICAM-1), a v b 3 Integrin, and GPIb a
Thomas Bombeli; Barbara R. Schwartz; John M. Harlan
Summary Although it has been reported that activated platelets can adhere to intact endothelium, the re- ceptors involved have not been fully characterized. Also, it is not clear whether activated plate- lets bind primarily to matrix proteins at sites of endothelial cell denudation or directly to endo- thelial cells. Thus, this study was designed to further clarify the mechanisms of
Microneural anastomosis using cyanoacrylate adhesives.
Choi, B-H; Kim, B-Y; Huh, J-Y; Lee, S-H; Zhu, S-J; Jung, J-H; Cho, B-P
We have developed a reliable method of microneural anastomosis using cyanoacrylate adhesives. This method involves overlapping the epineuriums of the two nerve ends and then applying two or three microdrops of cyanoacrylate adhesive on the surface of the epineurium just where the epineuriums overlap. The sciatic nerves of Sprague-Dawley rats were transected and repaired either with 10-0 nylon sutures or by using the described method. Histological evaluation showed no significant difference in the outcome of nerve regeneration between the two groups. It was concluded that the cyanoacrylate repair deserves to be considered as an alternative to the conventional suture technique in microneural anastomosis. PMID:15556326
Adhesive, elastomeric gel impregnating composition
Shaw, David Glenn (Tucson, AZ); Pollard, John Randolph (Tucson, AZ); Brooks, Robert Aubrey (Tijeras, NM)
An improved capacitor roll with alternating film and foil layers is impregnated with an adhesive, elastomeric gel composition. The gel composition is a blend of a plasticizer, a polyol, a maleic anhydride that reacts with the polyol to form a polyester, and a catalyst for the reaction. The impregnant composition is introduced to the film and foil layers while still in a liquid form and then pressure is applied to aid with impregnation. The impregnant composition is cured to form the adhesive, elastomeric gel. Pressure is maintained during curing.
Tanshinone I suppresses growth and invasion of human breast cancer cells, MDA-MB-231, through regulation of adhesion molecules.
Nizamutdinova, Irina Tsoy; Lee, Gyeong Won; Lee, Jong Sil; Cho, Min Kyung; Son, Kun Ho; Jeon, Su Jin; Kang, Sam Sik; Kim, Yeong Shik; Lee, Jae Heun; Seo, Han Geuk; Chang, Ki Churl; Kim, Hye Jung
The role of cell adhesion molecules has been studied extensively in the process of inflammation, and these molecules are critical components of carcinogenesis and cancer metastasis. This study investigated the effect of tanshinone I derived from the traditional herbal medicine, Salvia miltiorrhiza Bunge, on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-alpha (TNF-alpha)-stimulated endothelial cells. Furthermore, this study investigated the effect of tanshinone I on cancer growth, invasion and angiogenesis on human breast cancer cells MDA-MB-231, both in vitro and in vivo. Tanshinone I dose dependently inhibited ICAM-1 and VCAM-1 expressions in human umbilical vein endothelial cells (HUVECs) that were stimulated with TNF-alpha for 6 h. Pretreatment with tanshinone I significantly reduced adhesion of either monocyte U937 or MDA-MB-231 cells to HUVECs. Interestingly, the inhibitory effect of tanshinone I on monocyte and cancer cell adhesion to HUVECs was mimicked by transfection with ICAM-1 and VCAM-1 small interfering RNA. In addition, tanshinone I effectively inhibited TNF-alpha-induced production of vascular endothelial growth factor (VEGF) and VEGF-mediated tube formation in HUVECs. Tanshinone I also inhibited TNF-alpha-induced VEGF production in MDA-MB-231 cells and migration of MDA-MB-231 cells through extracellular matrix. Additionally, reduction of tumor mass volume and decrease of metastasis incidents by tanshinone I were observed in vivo. In conclusion, this study provides a potential mechanism for the anticancer effect of tanshinone I on breast cancer cells, suggesting that tanshinone I may serve as an effective drug for the treatment of breast cancer. PMID:18586687
Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway
Zhong, Xia, E-mail: email@example.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)] [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Li, Xiaonan; Liu, Fuli; Tan, Hui [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)] [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China); Shang, Deya, E-mail: email@example.com [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)] [Department of Emergency, Provincial Hospital Affiliated to Shandong University, Jinan 250021 (China)
Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.
Androgens inhibit tumor necrosis factor-?-induced cell adhesion and promote tube formation of human coronary artery endothelial cells.
Liao, Chun-Hou; Lin, Feng-Yen; Wu, Yi-No; Chiang, Han-Sun
Endothelial cells contribute to the function and integrity of the vascular wall, and a functional aberration may lead to atherogenesis. There is increasing evidence on the atheroprotective role of androgens. Therefore, we studied the effect of the androgens-testosterone and dihydrotestosterone-and estradiol on human coronary artery endothelial cell (HCAEC) function. We found by MTT assay that testosterone is not cytotoxic and enhances HCAEC proliferation. The effect of testosterone (10-50 nM), dihydrotestosterone (5-50 nM), and estradiol (0.1-0.4 nM) on the adhesion of tumor necrosis factor-? (TNF-?)-stimulated HCAECs was determined at different time points (12-96 h) by assessing their binding with human monocytic THP-1 cells. In addition, the expression of adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1), was determined by ELISA and Western blot analysis. Both testosterone and dihydrotestosterone attenuated cell adhesion and the expression of VCAM-1 and ICAM-1 in a dose- and time-dependent manner. Furthermore, androgen treatment for a longer duration inhibited cell migration, as demonstrated by wound-healing assay, and promoted tube formation on a Matrigel. Western blot analysis demonstrated that the expression of phosphorylated endothelial nitric oxide synthase (eNOS) increased, whereas that of inducible nitric oxide synthase (iNOS) decreased following the 96-h steroid treatment of TNF-?-stimulated HCAECs. Our findings suggest that androgens modulate endothelial cell functions by suppressing the inflammatory process and enhancing wound-healing and regenerative angiogenesis, possibly through an androgen receptor (AR)-dependent mechanism. PMID:22504554
21 CFR 175.125 - Pressure-sensitive adhesives.
Code of Federal Regulations, 2012 CFR
...finished pressure-sensitive adhesive. (8) 2-Hydroxy-1...the pressure-sensitive adhesive. (9) Butanedioic acid...finished pressure-sensitive adhesive. (b) Pressure-sensitive adhesives prepared from one or...
21 CFR 175.125 - Pressure-sensitive adhesives.
Code of Federal Regulations, 2011 CFR
...finished pressure-sensitive adhesive. (8) 2-Hydroxy-1...the pressure-sensitive adhesive. (9) Butanedioic acid...finished pressure-sensitive adhesive. (b) Pressure-sensitive adhesives prepared from one or...
21 CFR 175.125 - Pressure-sensitive adhesives.
Code of Federal Regulations, 2013 CFR
...finished pressure-sensitive adhesive. (8) 2-Hydroxy-1...the pressure-sensitive adhesive. (9) Butanedioic acid...finished pressure-sensitive adhesive. (b) Pressure-sensitive adhesives prepared from one or...
21 CFR 175.125 - Pressure-sensitive adhesives.
Code of Federal Regulations, 2014 CFR
...finished pressure-sensitive adhesive. (8) 2-Hydroxy-1...the pressure-sensitive adhesive. (9) Butanedioic acid...finished pressure-sensitive adhesive. (b) Pressure-sensitive adhesives prepared from one or...
21 CFR 175.125 - Pressure-sensitive adhesives.
Code of Federal Regulations, 2010 CFR
...finished pressure-sensitive adhesive. (8) 2-Hydroxy-1...the pressure-sensitive adhesive. (9) Butanedioic acid...finished pressure-sensitive adhesive. (b) Pressure-sensitive adhesives prepared from one or...
Tape-Smoothing Tool For Adhesion Tests
NASA Technical Reports Server (NTRS)
Allen, Peter B.
Small tool smoothes adhesive tape uniformly to ensure consistency and repeatability of tape-peel tests of adhesion of paint to substrate. Includes resilient pad covered with tough, smooth fabric. Internal spring regulates force applied to tape.
Evaluation of easily removable pellicle adhesive
NASA Astrophysics Data System (ADS)
Zhou, Nancy; Barrett, Monica; Nolan, Robert; Plouffe, Dennis; Ritter, Jason; Wagner, Alfred; Caterer, Michael; Mizoguchi, Takashi; Akutagawa, Satoshi; Duong, Kevin; Imai, Corbin; Wang, C. B.
With the advancement of technology, the need to produce flatter photomasks is critical to meet strict mask manufacturing requirements. Components such as pellicle mounting techniques, pellicle frame height, frame material and adhesive all play an important role in finished photomask flatness.1-5 In particular, recent studies have shown that adhesive flexibility affect final photomask flatness significantly.6 This has motivated pellicle suppliers to optimize adhesive properties in addition to evaluate new adhesives. The paper describes the joint evaluations between IBM, Toppan and MLI, performed to determine the effect of a new MLI adhesive on the distortion of photomasks. Due to the nature of this adhesive, minimal mounting force is required. As a result of utilizing extreme low mounting pressure, benefits such as decreased flatness distortion and ease of adhesive removal are observed. The goal of this paper is to evaluate this new adhesive offering and understand the various impacts it has on pelliclized photomasks for advanced technologies.
A thermally responsive, rigid, and reversible adhesive
Xiaofan Luo; Kathryn E. Lauber; Patrick T. Mather
In this paper we present the development of a unique self-adhesive material that, unlike conventional adhesives, maintains a high degree of rigidity at the ōadhesiveö state while possessing the ability to easily de-bond upon heating. Consequently, the material is both a rigid and a reversible adhesive. The material is an initially miscible blend of poly(?-caprolactone) (PCL) and diglycidyl ether of
Vascular and nonvascular expression of INCAM-110. A target for mononuclear leukocyte adhesion in normal and inflamed human tissues.
Rice, G. E.; Munro, J. M.; Corless, C.; Bevilacqua, M. P.
Inducible cell adhesion molecule 110 (INCAM-110), is a 110-kd adhesion receptor for lymphocytes and monocytes identified on cytokine-activated endothelium. Using immunoperoxidase techniques, little or no INCAM-110 was detected on endothelium in normal human tissues. In contrast, INCAM-110 was expressed in postcapillary venules in a variety of active inflammatory processes. In acute appendicitis, INCAM-110 was found coincident with strong expression of endothelial leukocyte adhesion molecule 1 (ELAM-1), a cytokine-inducible molecule that functions in neutrophil adhesion. However, in certain chronic inflammatory processes (eg, sarcoidosis), INCAM-110 was observed without simultaneous ELAM-1 expression. Anti-INCAM-110 antibody E1/6 also marked several extravascular cell types, including lymphoid dendritic cells, some tissue macrophages, synovial lining cells, and reactive mesothelial cells. These data suggest a role for endothelial INCAM-110 in the pathophysiology of both acute and chronic inflammatory reactions. Furthermore INCAM-110 may function as an adhesion molecule for mononuclear leukocytes in a variety of extravascular sites. Images Figure 1 Figure 2 PMID:1704191
Adhesion and aggregation of fine particles
Kevin Kendall; Carl Stainton
The influence of interparticle adhesion on the formation and properties of aggregates is reviewed. Increasing the adhesive forces between particles in an aggregate should raise the strength of the aggregate because each particle contact then requires more force for fracture. However, it is well known experimentally that strongly adhesive fine particles lead to fluffy structures which contain fewer contacts and
Mussel-Inspired Adhesives and Coatings
Bruce P. Lee; P. B. Messersmith; J. N. Israelachvili; J. H. Waite
Mussels attach to solid surfaces in the sea. Their adhesion must be rapid, strong, and tough, or else they will be dislodged and dashed to pieces by the next incoming wave. Given the dearth of synthetic adhesives for wet polar surfaces, much effort has been directed to characterizing and mimicking essential features of the adhesive chemistry practiced by mussels. Studies
Switchable Adhesion from Bicomponent Polymeric Brushes
Haris Retsos; Ganna Gorodyska; Costantino Creton
We investigated the adhesive and wetting properties of bicomponent polymeric brushes made from end functionalized hydrophilic and hydrophobic polymer chains. The molecular organization of the mixed brush could be varied reversibly by exposure to selective solvents for the two polymers. Adhesive properties were tested by debonding a flat ended probe from soft pressure-sensitive-adhesives (hydrophobic & hydrophilic) and wetting properties were
Photoresist substrate having robust adhesion
Dentinger, Paul M. (Sunol, CA)
A substrate material for LIGA applications w hose general composition is Ti/Cu/Ti/SiO.sub.2. The SiO.sub.2 is preferably applied to the Ti/Cu/Ti wafer as a sputtered coating, typically about 100 nm thick. This substrate composition provides improved adhesion for epoxy-based photoresist materials, and particularly the photoresist material SU-8.
Candida biofilms: is adhesion sexy?
Soll, David R
The development of Candida albicans biofilms requires two types of adhesion molecule - the Als proteins and Hwp1. Mutational analyses have recently revealed that these molecules play complementary roles, and their characteristics suggest that they may have evolved from primitive mating agglutinins. PMID:18727911
Adhesion between Nanoscale Rough Surfaces
Yakov I. Rabinovich; Joshua J. Adler; Ali Ata; Rajiv K. Singh; Brij M. Moudgil
Nanoscale surface roughness strongly affects the adhesion force between surfaces. In this investigation, a model that more accurately describes the size of an asperity based on the measurable parameters of root-mean-square (rms) roughness and the distance between the asperities is derived. The radius of the asperity from the proposed model is much larger than the radius used in previous approaches,
Ginsenoside Rg3 inhibits lipopolysaccharide-induced adhesion molecule expression in human umbilical vein endothelial cell and C57BL/6 mice.
Cho, Young-Suk; Kim, Chan Hyung; Kim, Han Na; Ha, Tae-Sun; Ahn, Hee Yul
Intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), P- and E-selectin play a key role for initiation of vascular inflammation. Ginsenoside, a class of steroid glycosides, is abundant in Panax ginseng root, which has been used for health promotion in Korea. In this study, we investigated the mechanism by which ginsenoside Rg3 may inhibit ICAM-1 and VCAM-1 expressions stimulated with lipopolysaccharide (LPS) in human umbilical vein endothelial cell (HUVEC) and C57BL/6 mice. LPS increased ICAM-1 and VCAM-1 expression. Ginsenoside Rg3 prevented LPS-mediated increase of ICAM-1 and VCAM-1 expression. LPS induced IkappaB? (I?B?) degradation within 1 hr. Ginsenoside Rg3 prevented the I?B? degradation stimulated with LPS. Moreover, ginsenoside Rg3 reduced LPS-mediated THP-1 monocyte adhesion to HUVEC, in a concentration-dependent manner. In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, which was prevented by ginsenoside Rg3. These data provide a novel mechanism where the ginsenoside Rg3 may provide direct vascular benefits with inhibition of leukocyte adhesion into vascular wall thereby providing prevention against vascular inflammatory disease. PMID:25985577
Designing Hydrogel Adhesives for Corneal Wound Repair
Grinstaff, Mark W.
Today, corneal wounds are repaired using nylon sutures. Yet there are a number of complications associated with suturing the cornea, and thus there is interest in an adhesive to replace or supplement sutures in the repair of corneal wounds. We are designing and evaluating corneal adhesives prepared from dendrimers ¢ single molecular weight, highly branched polymers. We have explored two strategies to form these ocular adhesives. The first involves a photocrosslinking reaction and the second uses a peptide ligation reactions to couple the individual dendrimers together to from the adhesive. These adhesives were successfully used to repair corneal perforations, close the flap produced in a LASIK procedure, and secure a corneal transplant. PMID:17889330
Adhesive Behavior of Single Carbon Nanotubes
NASA Astrophysics Data System (ADS)
Maeno, Yohei; Ishikawa, Atsunori; Nakayama, Yoshikazu
We examined the adhesion of a carbon nanotube (CNT) tip using a manipulation technique with a transmission electron microscope. In addition, we estimated the maximum normal adhesion possibility of a CNT-based gecko tape. The adhesive behavior of a single isolated CNT to Au solid surfaces has high normal strength (6.84 nN), which has a linear relation to the cross section of a CNT, indicating the mechanism: van der Waals force was inferred from the contact of two flat surfaces. Adhesion measurements conducted on several surface materials verify that the surface chemistry affects adhesive properties of CNT tips.
Wet Adhesion and Adhesive Locomotion of Snails on AntiAdhesive Non-Wetting Surfaces
Neil J. Shirtcliffe; Glen McHale; Michael I. Newton
Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However,
Pentraxin 3 as a biomarker of local inflammatory response to vascular injury in systemic lupus erythematosus.
Cie?lik, Pawe?; Hrycek, Antoni
Systemic lupus erythematosus (SLE) is an autoimmune disorder with organ injury related to vasculitis. Inflammation of blood vessels results from auto-immunological activation of endothelial cells. The pentraxin 3 (PTX3), might act as an indicator of vasculitides in many diseases. The aim of this study was to determine whether PTX3 might be useful as a marker of vascular injury in SLE. This study was carried out in a group of 56 SLE women, and in the 28 female volunteers control group. All participants' plasma and serum samples were collected to estimate concentrations (ELISA) of PTX3, soluble thrombomodulin, soluble E-selectin (sE-selectin), soluble P-selectin (sP-selectin), soluble form of vascular cell adhesion molecule 1 (sVCAM-1), soluble inter-cellular adhesion molecule-1 (sICAM-1), soluble platelet endothelial cell adhesion molecule 1, monocyte chemotactic protein-1 (MCP-1) and von Willebrand factor (vWF) activity. Anthropometric, demographic and lifestyle characteristics of SLE patients were also performed. The SLE patients had higher PTX3, vWF, MCP-1, sE-selectin and sVCAM-1 levels than the controls (1.82?▒?1.56?ng/mL, 237?▒?101%, 70.05?▒?18.31?ng/mL, 111.16?▒?49.15?ng/mL and 978.78?▒?462.35?ng/mL vs. 0.86?▒?0.40?ng/mL, 138?▒?43%, 58.56?▒?13.91?ng/mL, 66.04?▒?27.18?ng/mL and 499.07?▒?125.67?ng/mL, respectively). The independent factors affecting PTX3 expression included Systemic Lupus Erythematosus Disease Activity Index, prednisone dose and anemia severity. Moreover, the PTX3 areas under the curve-receiver operating characteristics curves 0.717?▒?0.056 with cut-off level of 1.96?ng/mL was comparable to vWF, MCP-1, sE-selectin, sP-selectin and sICAM-1. PTX3 and sVCAM-1 were the only factors related to SLE activity. Other vascular injury indicators associated with PTX3 were vWF and sVCAM-1. In conclusion, PTX3 concentrations in SLE patients might serve as a indicator of the activation/dysfunction of vascular endothelium. PMID:25401491
Angiopoietin-1 and Vascular Endothelial Growth Factor Regulation of Leukocyte Adhesion to Endothelial Cells: Role of Nuclear Receptor-77
Ismail, Hodan; Mofarrahi, Mahroo; Echavarria, Raquel; Harel, Sharon; Verdin, Eric; Lim, Hyung W.; Jin, Zheng-Gen; Sun, Jianxin; Zeng, Huiyan; Hussain, Sabah N.A.
Objective Vascular endothelial growth factor (VEGF) promotes leukocyte adhesion to endothelial cells (ECs). Angiopoietin-1 (Ang-1) inhibits this response. Nuclear receptor-77 (Nur77) is a proangiogenic nuclear receptor. In the present study, we assessed the influence of Ang-1 and VEGF on Nur77 expression in ECs, and evaluated its role in Ang-1/VEGF-mediated leukocyte adhesion. Methods and Results Expression of Nur77 was evaluated with real-time polymerase chain reaction and immunoblotting. Adhesion of leukocytes to ECs was monitored with inverted microscopy. Nur77 expression or activity was inhibited using adenoviruses expressing dominant-negative form of Nur77, retroviruses expressing Nur77 in the antisense direction, and small interfering RNA oligos. Both Ang-1 and VEGF induce Nur77 expression, by >5- and 30-fold, respectively. When combined, Ang-1 potentiates VEGF-induced Nur77 expression. Ang-1 induces Nur77 through the phosphoinositide 3-kinase and extracellular signal-regulated protein kinase 1/2 pathways. VEGF induces Nur77 expression through the protein kinase D/histone deacetylase 7/myocyte enhancer factor 2 and extracellular signal-regulated protein kinase 1/2 pathways. VEGF induces nuclear factor-kappaB transcription factor, vascular cell adhesion molecule-1, and E-selectin expressions, and promotes leukocyte adhesion to ECs. Ang-1 inhibits these responses. This inhibitory effect of Ang-1 disappears when Nur77 expression is disrupted, restoring the inductive effects of VEGF on adhesion molecule expression, and increased leukocyte adhesion to ECs. Conclusion Nur77 promotes anti-inflammatory effects of Ang-1, and functions as a negative feedback inhibitor of VEGF-induced EC activation. PMID:22628435
Theory of adhesion: role of surface roughness.
Persson, B N J; Scaraggi, M
We discuss how surface roughness influences the adhesion between elastic solids. We introduce a Tabor number which depends on the length scale or magnification, and which gives information about the nature of the adhesion at different length scales. We consider two limiting cases relevant for (a) elastically hard solids with weak (or long ranged) adhesive interaction (DMT-limit) and (b) elastically soft solids with strong (or short ranged) adhesive interaction (JKR-limit). For the former cases we study the nature of the adhesion using different adhesive force laws (F ? u(-n), n = 1.5-4, where u is the wall-wall separation). In general, adhesion may switch from DMT-like at short length scales to JKR-like at large (macroscopic) length scale. We compare the theory predictions to results of exact numerical simulations and find good agreement between theory and simulation results. PMID:25273455
Bio-inspired adhesion: local chemical environments impact adhesive stability
NASA Astrophysics Data System (ADS)
Gebbie, Matthew A.; Rapp, Michael V.; Yu, Jing; Wei, Wei; Waite, J. Herbert; Israelachvili, Jacob N.
3,4-dihydroxyphenylalanine (Dopa) is an amino acid that is naturally synthesized by marine mussels and exhibits the unique ability to strongly bind to surfaces in aqueous environments. However, the Dopa functional group undergoes auto-oxidation to a non-adhesive quinone form in neutral to basic pH conditions, limiting the utilization of Dopa in biomedical applications. In this work, we performed direct surface force measurements with in situ electrochemical control across a Dopa-rich native mussel foot protein (mfp-5), as well as three simplified model peptide sequences. We find that the neighboring peptide residues can significantly impact the redox stability of Dopa functional groups, with lysine residues imparting a substantial degree of Dopa redox stabilization. Surprisingly, the local chemical environments only minimally impact the magnitude of the adhesion forces measured between molecularly-smooth mica and gold surfaces. Our results provide molecular level insight into approaches that can be used to mitigate the detrimental impact of Dopa auto-oxidation, thus suggesting new molecular design strategies for improving the performance of Dopa-based underwater adhesives.
Particle adhesion in powder coating
Mazumder, M.K.; Wankum, D.L.; Knutson, M.; Williams, S. [Univ. of Arkansas, Little Rock, AR (United States); Banerjee, S. [Univ. of Georgia, Athens, GA (United States)
Electrostatic powder coating is a widely used industrial painting process. It has three major advantages: (1) it provides high quality durable finish, (2) the process is environmentally friendly and does not require the use of organic solvents, and (3) it is economically competitive. The adhesion of electrostatically deposited polymer paint particles on the grounded conducting substrate depends upon many parameters: (a) particle size and shape distributions, (b) electrostatic charge distributions, (c) electrical resistivity, (d) dielectric strength of the particles, (e) thickness of the powder film, (f) presence and severity of the back corona, and (g) the conductivity and surface properties of the substrate. The authors present a model on the forces of deposition and adhesion of corona charged particles on conducting substrates.
Tumor Cell Extravasation Mediated by Leukocyte Adhesion is Shear Rate Dependent on IL-8 Signaling*
Liang, Shile; Hoskins, Meghan; Dong, Cheng
To complete the metastatic journey, cancer cells have to disseminate through the circulation and extravasate to distal organs. However, the extravasation process, by which tumor cells leave a blood vessel and invade the surrounding tissue from the microcirculation, remains poorly understood at the molecular level. In this study, tumor cell adhesion to the endothelium (EC) and subsequent extravasation were investigated under various flow conditions. Results have shown polymorphonuclear neutrophils (PMNs) facilitate melanoma cell adhesion to the EC and subsequent extravasation by a shear-rate dependent mechanism. Melanoma cell-PMN interactions are mediated by the binding between intercellular adhesion molecule-1 (ICAM-1) on melanoma cells and ?2 integrins on PMNs. In addition, the fluid convection affects the extent of activation of ?2 integrins on PMNs by endogenously secreted interleukin 8 (IL-8) within the tumor microenvironment. Results also indicate that shear rate affects the binding kinetics between PMNs and melanoma cells, which may contribute to the shear-rate dependence of melanoma extravasation in a shear flow when mediated by PMNs. PMID:20379392
6-Methylsulfinylhexyl isothiocyanate modulates endothelial cell function and suppresses leukocyte adhesion.
Okamoto, Takayuki; Akita, Nobuyuki; Nagai, Masashi; Hayashi, Tatsuya; Suzuki, Koji
6-Methylsulfinylhexyl isothiocyanate (6-MSITC) is an active compound in wasabi (Wasabia japonica Matsum.), which is one of the most popular spices in Japan. 6-MSITC suppresses lipopolysaccharide-induced macrophage activation, arachidonic- or adenosine diphosphate-induced platelet activation, and tumor cell proliferation. These data indicate that 6-MSITC has several biological activities involving anti-inflammatory, anti-coagulant, and anti-apoptosis properties. Endothelial cells (ECs) maintain vascular homeostasis and play crucial roles in crosstalk between blood coagulation and vascular inflammation. In this study, we determined the anti-coagulant and anti-inflammatory effects of 6-MSITC on human umbilical vein endothelial cells (HUVECs). 6-MSITC slightly reduced tissue factor expression, but did not alter von Willebrand factor release in activated HUVECs. 6-MSITC modulated the generation of activated protein C, which is essential for negative regulation of blood coagulation, on normal ECs. In addition, 6-MSITC reduced tumor necrosis factor-? (TNF-?)-induced interleukin-6 and monocyte chemoattractant protein-1 expression. 6-MSITC markedly attenuated TNF-?-induced adhesion of human monoblast U937 cells to HUVECs and reduced vascular cell adhesion molecule-1 and E-selectin mRNA expression in activated ECs. These results showed that 6-MSITC modulates EC function and suppresses cell adhesion. This study provides new insight into the mechanism of the anti-inflammatory effect of 6-MSITC, suggesting that 6-MSITC has therapeutic potential as a treatment for vasculitis and vascular inflammation. PMID:23760613
NSDL National Science Digital Library
Water sticks to all kinds of things in nature Ś flowers, leaves, spider webs - and doesn't stick to others, such as a duck's back. In this activity, learners explore water adhesion (when water sticks to something else) and cohesion (when water sticks to itself), and how these forces combine to move water along a string. As part of the activity learners come to understand what "variable" means in the context of an experiment.
Tissue Adhesives as Active Implants
Boaz Mizrahi; Christopher Weldon; Daniel S. Kohane
\\u000a Tissue adhesives are substances that hold tissues together, and could be broadly applicable in medicine and surgery. In appropriate\\u000a circumstances, such materials could be attractive alternatives to sutures and staples since they can be applied more quickly,\\u000a causes less pain and may require less equipment. In addition, there is no risk to the practitioner from sharp instruments\\u000a (Singer et al.,
76 FR 59087 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Adhesives and Sealants Rule
Federal Register 2010, 2011, 2012, 2013, 2014
...commercially-used adhesive and sealant products...4.0--Adhesives and Sealants under Regulation...and use of adhesives, sealants, adhesive primers, or sealant primers...application of adhesives, sealants, adhesive primers, and sealant primers...
Adhesion enhancement of biomimetic dry adhesives by nanoparticle in situ synthesis
NASA Astrophysics Data System (ADS)
DĒaz Tķllez, J. P.; Harirchian-Saei, S.; Li, Y.; Menon, C.
A novel method to increase the adhesion strength of a gecko-inspired dry adhesive is presented. Gold nanoparticles are synthesized on the tips of the microfibrils of a polymeric dry adhesive to increase its Hamaker constant. Formation of the gold nanoparticles is qualitatively studied through a colour change in the originally transparent substance and quantitatively analysed using ultraviolet-visible spectrophotometry. A pull-off force test is employed to quantify the adhesion enhancement. Specifically, adhesion forces of samples with and without embedded gold nanoparticles are measured and compared. The experimental results indicate that an adhesion improvement of 135% can be achieved.
Chitosan Adhesive Films for Photochemical Tissue Bonding
NASA Astrophysics Data System (ADS)
Lauto, Antonio; Mawad, Damia; Barton, Matthew; Piller, Sabine C.; Longo, Leonardo
Photochemical tissue bonding (PTB) is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB) between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser-activated. Materials and Methods. Adhesive films, based on chitosan and containing ś0.1wt% RB were manufactured and bonded to calf intestine by a solid state laser (wavelength = 532 nm, Fluence ś110 J/cm2, spot size ś5 mm). A single-column tensiometer, interfaced with a personal computer, tested the bonding strength. K-type thermocouples recorded the temperature (T) at the adhesive-tissue interface during laser irradiation. Human fibroblasts were also seeded on the adhesive and cultured for 48 hours to assess cell growth. Results and Conclusion. The RB-chitosan adhesive bonded firmly to the intestine (15▒2 kPa, n = 31). The adhesion strength dropped to 0.5▒0.1 kPa (n = 8) when the laser was not applied to the adhesive. The average temperature of the adhesive increased from 26 ░C to 32 ░C during laser exposure. Fibroblasts grew confluent on the adhesive without morphological changes. A new biocompatible chitosan adhesive has been developed that bonds photochemically to tissue with minimal temperature increase.
Activation of nuclear factor-kappa B and cell adhesion molecule mRNA expression in duodenal mucosa of dogs with lymphocytic-plasmacytic enteritis.
Okanishi, Hiroki; Kabeya, Hidenori; Maruyama, Soichi; Kagawa, Yumiko; Watari, Toshihiro
Lymphocytic-plasmacytic enteritis (LPE) is the most common form of inflammatory bowel disease (IBD) affecting the canine small intestine; however, the molecular basis of the pathogenesis remains unclear. It has recently been hypothesized that the primary defect is impaired innate immune function, as is the case for human IBD. Nuclear factor-kappa B (NFkappaB) plays a central role in innate immunity, and is a major transcriptional regulator of several proinflammatory cytokines, pattern recognition receptors (PRRs) such as toll-like receptors (TLRs), nucleotide-binding oligomerization domain-like receptors and cell adhesion molecules (CAMs). The purpose of this study was to evaluate, in the duodenal mucosa of 21 dogs with LPE and 8 control dogs, the degree of NFkappaB activity and the mRNA expression of two selected cytokines, nucleotide oligomerization domain two (NOD2) receptor and three selected CAMs, all of which are regulated by NFkappaB, using the electrophoretic mobility shift assay and real-time reverse transcription PCR. NFkappaB binding activity was significantly higher in the inflamed duodenal mucosa of the LPE dogs as compared to healthy controls. Furthermore, expression of mRNA for intercellular cell adhesion molecule 1 (ICAM-1) and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) was significantly higher and vascular cell adhesion molecule 1 (VCAM-1) mRNA significantly lower in LPE dogs than in healthy controls. However, there was no significant difference in the mRNA levels for TNF?, IL1? and NOD2 between the two groups. These results suggest that NFkappaB and CAMs may play important roles in the pathogenesis of canine LPE. PMID:23786670
Sundew adhesive: a naturally occurring hydrogel.
Huang, Yujian; Wang, Yongzhong; Sun, Leming; Agrawal, Richa; Zhang, Mingjun
Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 ▒ 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of mammal cells, evidence is sufficient to propose that sundew adhesive is a promising nanomaterial worth further exploitation in the field of tissue engineering. PMID:25948615
Chlorella 11-Peptide Inhibits the Production of Macrophage-Induced Adhesion Molecules and Reduces Endothelin-1 Expression and Endothelial Permeability
Shih, Mei Fen; Chen, Lih Chi; Cherng, Jong Yuh
The inflammation process in large vessels involves the up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are also known as the markers of atherosclerosis. We have reported that Chlorella 11-peptide exhibited effective anti-inflammatory effects. This peptide with an amino sequence Val-Glu-Cys-Tyr-Gly-Pro-Asn-Arg-Pro-Gln-Phe was further examined for its potential in preventing atherosclerosis in this study. In particular, the roles of Chlorella 11-peptide in lowering the production of vascular adhesion molecules, monocyte chemoattractant protein (MCP-1) and expression of endothelin-1 (ET-1) from endothelia (SVEC4-10 cells) were studied. The production of E-selectin, ICAM-1, VCAM-1 and MCP-1 in SVEC4-10 cells was measured with ELISA. The mRNA expression of ET-1 was analyzed by RT-PCR and agarose gel. Results showed that Chlorella 11-peptide significantly suppressed the levels of E-selectin, ICAM, VCAM, MCP-1 as well as ET-1 gene expression. The inhibition of ICAM-1 and VCAM-1 production by Chlorella 11-peptide was reversed in the presence of protein kinase A inhibitor (H89) which suggests that the cAMP pathway was involved in the inhibitory cause of the peptide. In addition, this peptide was shown to reduce the extent of increased intercellular permeability induced by combination of 50% of lipopolysaccharide (LPS)-activated RAW 264.7 cells medium and 50% normal SEVC cell culture medium (referred to as 50% RAW-conditioned medium). These data demonstrate that Chlorella 11-peptide is a promising biomolecule in preventing chronic inflammatory-related vascular diseases. PMID:24129228
Rabbit sera containing compound danshen dripping pill attenuate leukocytes adhesion to TNF-alpha--activated human umbilical vein endothelial cells by suppressing endothelial ICAM-1 and VCAM-1 expression through NF-kappaB signaling pathway.
Xu, Haibo; Wang, Dejian; Peng, Cheng; Huang, Xiushen; Ou, Ming; Wang, Ningsheng; Wang, Peixun; Zhou, Lijuan; Ye, Xiaolin
The adherence to circulating leukocytes, such as monocytes and neutrophils, to vascular endothelial cells is of central importance to the pathogenesis of various cardiovascular diseases (CVDs) including atherosclerosis and myocardial ischemia-reperfusion injury. Compound danshen dripping pill (CDDP; Fufang Danshen Diwan in Chinese), namely cardiotonic pill, is extensively used for CVDs medication in China and some other countries. Here, we sought to investigate the effect of CDDP on leukocytes binding to vascular endothelial cells and elaborate the possibly underlying mechanism. Using seropharmacological method, rabbit sera containing CDDP were shown to mitigate the adhesiveness of monocytes and neutrophils to tumor necrosis factor alpha-stimulated human umbilical vein endothelial cells in dose and time-dependent manners, alleviate the levels of intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 messenger RNA and protein dose dependently and also encumber I?B? degradation, p65 nuclear translocation, nuclear factor-kappaB (NF-?B) DNA-binding activity, and NF-?B-responsive gene transcription in tumor necrosis factor alpha-activated human umbilical vein endothelial cells. This study suggests that CDDP protects against CVDs potentially by attenuation of leukocytes-endothelium adhesion cascade via lessening endothelial cell adhesion molecules expression and NF-?B signaling pathway activity. PMID:24710469
Effects of an energy-restricted diet rich in plant-derived ?-linolenic acid on systemic inflammation and endothelial function in overweight-to-obese patients with metabolic syndrome traits.
Egert, Sarah; Baxheinrich, Andrea; Lee-Barkey, Young Hee; Tschoepe, Diethelm; Wahrburg, Ursel; Stratmann, Bernd
Plant-derived ?-linolenic acid (ALA) may reduce the risk of CVD, possibly by decreasing systemic inflammation and improving endothelial function. In the present study, the effects of a hypoenergetic diet rich in ALA (3Ę4Āg/d) on the biomarkers of systemic inflammation and vascular function were investigated in eighty-one overweight-to-obese patients with metabolic syndrome traits in comparison with a hypoenergetic diet low in ALA (0Ę9Āg/d, control). After a 6-month dietary intervention, there were significant decreases in the serum concentrations of C-reactive protein (CRP), TNF-?, IL-6, soluble intercellular adhesion molecule-1 (sICAM-1), soluble endothelial selectin (sE-selectin) and asymmetric dimethylarginine in both dietary groups. However, no inter-group differences were observed for all these changes. The serum concentration of YKL-40 (human cartilage glycoprotein 39 or chitinase-3-like protein 1) decreased after the ALA diet when compared with the control diet (P<Ā0Ę05 for timeĀūĀtreatment interaction). Plasma concentrations of fibrinogen did not significantly change in the two dietary groups. The decreases in the serum concentrations of sICAM-1, sE-selectin, CRP and YKL-40 were significantly correlated with the decreases in body fat mass. In conclusion, the present study indicates that in overweight-to-obese patients with metabolic syndrome traits, both vascular function and inflammation are improved during body-weight loss. The high ALA intake led to a more pronounced reduction in the serum concentration of YKL-40 compared with the intake of the low-ALA control diet, indicating the existence of independent favourable physiological effects of ALA during weight loss. PMID:25180479
Neutrophil apoptosis: impact of granulocyte macrophage colony stimulating factor on cell survival and viability in chronic kidney disease and hemodialysis patients
Zahran, Nariman; Sayed, Azza; William, Iman; Sabry, Omar; Rafaat, Manar
Introduction Altered neutrophil apoptosis might be responsible for recurrent bacterial infections encountered in hemodialysis (HD) and chronic kidney disease (CKD) patients. This work was designed to assess the neutrophil apoptotic activity and the impact of implementation of granulocyte macrophage colony stimulating factor (GM-CSF), as a survival factor, on neutrophil apoptosis among these patients. Material and methods Twenty-five patients on regular HD along with 34 CKD patients on conservative treatment, as well as 15 healthy controls, were investigated for apoptotic rate via assessment of neutrophil expression of Annexin-V by flow cytometry, before and after 20 h culture in absence and presence of GM-CSF. Neutrophil viability was determined using light microscopy. The preservation of neutrophil activation in these patients was analyzed by flow cytometric CD18 neutrophil expression. Chronic inflammatory state was evaluated by estimating C-reactive protein (CRP) and soluble intercellular adhesion molecule-1 (sICAM-1). Obtained data were statistically analyzed. Results Compared to controls, both HD and CKD groups had a significant increase of Annexin-V and CD18 expression and significant decrease in neutrophil viability. Culture of their neutrophils with GM-CSF showed significant decrease of apoptosis accompanied by improvement of neutrophil viability compared to their cultured cells without GM-CSF. These patients also showed significant elevation of CRP and sICAM-1. Conclusions Granulocyte macrophage colony stimulating factor demonstrated an evident impact on improving in vitro neutrophil survival and viability in HD and CKD patients. Therefore, this may represent promising preventive and/or therapeutic strategies against infection frequently observed in these patients and causing morbidity and mortality. PMID:24482640
Functionally Graded Adhesives for Composite Joints
NASA Technical Reports Server (NTRS)
Stapleton, Scott E.; Waas, Anthony M.; Arnold, Steven M.
Adhesives with functionally graded material properties are being considered for use in adhesively bonded joints to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. An enhanced joint finite element, which uses an analytical formulation to obtain exact shape functions, is used to model the joint. Furthermore, proof of concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint.
Mussel-Inspired Adhesives and Coatings
Lee, Bruce P.; Messersmith, P.B.; Israelachvili, J.N.; Waite, J.H.
Mussels attach to solid surfaces in the sea. Their adhesion must be rapid, strong, and tough, or else they will be dislodged and dashed to pieces by the next incoming wave. Given the dearth of synthetic adhesives for wet polar surfaces, much effort has been directed to characterizing and mimicking essential features of the adhesive chemistry practiced by mussels. Studies of these organisms have uncovered important adaptive strategies that help to circumvent the high dielectric and solvation properties of water that typically frustrate adhesion. In a chemical vein, the adhesive proteins of mussels are heavily decorated with Dopa, a catecholic functionality. Various synthetic polymers have been functionalized with catechols to provide diverse adhesive, sealant, coating, and anchoring properties, particularly for critical biomedical applications. PMID:22058660
Control of vascular permeability by adhesion molecules.
Sarelius, Ingrid H; Glading, Angela J
Vascular permeability is a vital function of the circulatory system that is regulated in large part by the limited flux of solutes, water, and cells through the endothelial cell layer. One major pathway through this barrier is via the inter-endothelial junction, which is driven by the regulation of cadherin-based adhesions. The endothelium also forms attachments with surrounding proteins and cells via 2 classes of adhesion molecules, the integrins and IgCAMs. Integrins and IgCAMs propagate activation of multiple downstream signals that potentially impact cadherin adhesion. Here we discuss the known contributions of integrin and IgCAM signaling to the regulation of cadherin adhesion stability, endothelial barrier function, and vascular permeability. Emphasis is placed on known and prospective crosstalk signaling mechanisms between integrins, the IgCAMs- ICAM-1 and PECAM-1, and inter-endothelial cadherin adhesions, as potential strategic signaling nodes for multipartite regulation of cadherin adhesion. PMID:25838987
Adhesion and wear resistance of materials
NASA Technical Reports Server (NTRS)
Buckley, D. H.
Recent studies into the nature of bonding at the interface between two solids in contact or a solid and deposited film have provided a better understanding of those properties important to the adhesive wear resistance of materials. Analytical and experimental progress are reviewed. For simple metal systems the adhesive bond forces are related to electronic wave function overlap. With metals in contact with nonmetals, molecular-orbital energy, and density of states, respectively can provide insight into adhesion and wear. Experimental results are presented which correlate adhesive forces measured between solids and the electronic surface structures. Orientation, surface reconstruction, surface segregation, adsorption are all shown to influence adhesive interfacial strength. The interrelationship between adhesion and the wear of the various materials as well as the life of coatings applied to substrates are discussed. Metallic systems addressed include simple metals and alloys and these materials in contact with themselves, both oxide and nonoxide ceramics, diamond, polymers, and inorganic coating compounds, h as diamondlike carbon.
Elastic beam over an adhesive wavy foundation
NASA Astrophysics Data System (ADS)
Carbone, Giuseppe; Decuzzi, Paolo
The adhesive behavior of a thin infinitely long elastic beam resting over a wavy rigid foundation with wavelength ? is studied. Three governing parameters have been identified describing the physical and geometrical properties of the system: the dimensionless surface energy ?ś=?/Es, the dimensionless amplitude hś=h/? of the substrate, and thickness of the beam sś=s/?. Analyzing the variation of the total energy of the system as a function of the governing parameters three different adhesive regimes have been individuated: full adhesion, partial adhesion, and no adhesion (point contact). An effective surface energy has been considered showing that the effect of surface waviness could be beneficial in increasing the adhesive strength of the system. In particular for ?ś=1.0 and sś=0.1, it has been evaluated a maximum effective interface energy of about 1.4? under full contact conditions. Larger amplifications are expected for higher ?ś and smaller sś.
Colloidal adhesion to hydrophilic membrane surfaces
Jonathan A. Brant; Amy E. Childress
Colloidal adhesion to membrane surfaces is an important parameter in determining membrane fouling propensity and in optimizing membrane cleaning strategies. It has previously been demonstrated that acid¢base interactions can significantly affect colloid¢membrane interaction as a colloid approaches a membrane surface, however, the effect of acid¢base interactions on adhesion has received less attention. In this investigation, the approach and adhesion of
Double-Adhesive Tape Test Reduces Waste
NASA Technical Reports Server (NTRS)
Lee, L. C.; Reed, M. W.
New method for testing peel strength of particular thermal-control tape used on Space Shuttle orbiter radiators requires only half amount of tape of method previously employed. Thermal-control tape consists of layers of FEP, silver, Inconel metal, adhesive, Kapton Film, and second adhesive layer. Method also avoids cost of labor and materials to prepare second test coupon and can be adapted for testing other types of double-faced adhesive tapes in military, industrial and consumer applications.
Improved Cure-in-Place Silicone Adhesives
NASA Technical Reports Server (NTRS)
Blevins, C. E.; Sweet, J.; Gonzalez, R.
Two improved cure-in-place silicone-elastomer-based adhesives have low thermal expansion and low thermal conductivity. Adhesives are flexible at low temperature and withstand high temperatures without disintegrating. New ablative compounds were initially developed for in-flight repair of insulating tile on Space Shuttle orbiter. Could find use in other applications requiring high-performance adhesives, such as sealants for solar collectors.
Biodegradable polymer adhesives, hybrids and nanomaterials
Andreas Mylonakis
Biodegradable polymeric products and organic-inorganic hybrid materials for a diversity of applications are the two main fields on which this research has been focused. A novel biodegradable adhesive, which mimics marine adhesive proteins, has been synthesized by the covalent incorporation of 3,4-dihydroxybenzoic acid onto the chitosan backbone. The adhesive strength of these materials varies with the molecular weight of the
Science of Friction¢Adhesive Joints
Eugenio Dragoni; Pierfranco Mauri
\\u000a This chapter addresses the fundamental properties of hybrid friction¢adhesive joints which combine any form of mechanical\\u000a tightening (stimulus for friction forces) with anaerobic adhesives. By filling the voids around the microareas of true metal-to-metal\\u000a contact between the mating parts, anaerobic adhesives allow the full area involved by the engagement to be usefully exploited.\\u000a Advantages ranging from sealing action, fretting suppression,
Efficacy of antibodies to adhesion molecules, CD11a or CD18, in rabbit models of uveitis.
Rosenbaum, J T; Boney, R S
Adhesion molecules play a critical role in leukocyte emigration to a site of inflammation. In order to assess the potential therapeutic benefit of blocking adhesion molecule function in anterior uveitis, the efficacy of antibodies to specific adhesion molecules was tested in 3 separate rabbit models of anterior uveitis. Antibodies to two different leukocyte molecules, CD11a and CD18, and antibodies to the endothelial ligand for CD11a/CD18, ICAM-1 (intercellular adhesion molecule-1, CD54), were studied in inflammation after intravitreally injected interleukin-1, intravitreally injected endotoxin, or an ocular reversed passive Arthus reaction. The CD18 antibody (2 mg/kg intravenously) reduced the cellular infiltrate with each of these 3 models. The antibody to CD11a was equally effective but was tested only in the IL-1-induced model. The antibody to ICAM-1 reduced the cellular infiltrate associated with this model, but the results did not reach statistical significance. None of the antibodies was able to reduce the associated increase in vascular permeability as measured by protein in the aqueous humor. The antibody to CD18 failed to reduce the inflammation if it was administered 24 hours after the intravitreally injected endotoxin. These observations demonstrate that leukocyte migration into the anterior segment of the eye is dependent on the CD11a/CD18 complex. PMID:7903235
Effects of the Tumor-Leukocyte Microenvironment on Melanoma¢Neutrophil Adhesion to the Endothelium in a Shear Flow
Liang, Shile; Hoskins, Meghan; Khanna, Payal; Kunz, Robert F.; Dong, Cheng
The primary cause of cancer mortality is not attributed to primary tumor formation, but rather to the growth of metastases at distant organ sites. Tumor cell adhesion to blood vessel endothelium (EC) and subsequent transendothelial migration within the circulation are critical components of the metastasis cascade. Previous studies have shown polymorphonuclear neutrophils (PMNs) may facilitate melanoma cell adhesion to the EC and subsequent extravasation under flow conditions. The melanoma cell¢PMN interactions are found to be mediated by the binding between intercellular adhesion molecule-1 (ICAM-1) on melanoma cells and ?2 integrin on PMNs and by endogenously secreted interleukin 8 (IL-8) within the tumor-leukocyte microenvironment. In this study, the effects of fluid convection on the IL-8-mediated activation of PMNs and the binding kinetics between PMNs and melanoma cells were investigated. Results indicate that the shear rate dependence of PMN¢melanoma cell adhesion and melanoma cell extravasation is due, at least partly, to the convection of tumor-secreted proinflammatory cytokine IL-8. PMID:19865613
Comparing mathematical models of cell adhesion in tumors
Vipin Narang; Shek Yoon Wong; Shiang Rong Leong; Jean-Pierre Abastado; Alexandre Gouaillard
Cancer progression accompanies changes in cell adhesion characteristics, which is crucial for cancer cell invasion and metastasis. Drugs altering cell adhesion have been suggested as a possible therapeutic treatment for cancer. Tumor cell adhesion is thus an important topic of current investigation. Recently individual cell (agent)-based in silico tumor models have incorporated mathematical models of cell adhesion. However, cell adhesion
Investigation of package sealing using organic adhesives
NASA Technical Reports Server (NTRS)
Perkins, K. L.; Licari, J. J.
A systematic study was performed to evaluate the suitability of adhesives for sealing hybrid packages. Selected adhesives were screened on the basis of their ability to seal gold-plated Kovar butterfly-type packages that retain their seal integrity after individual exposures to increasingly severe temperature-humidity environments. Tests were also run using thermal shock, temperature cycling, mechanical shock and temperature aging. The four best adhesives were determined and further tested in a 60 C/98% RH environment and continuously monitored in regard to moisture content. Results are given, however, none of the tested adhesives passed all the tests.
Computational Contact Formulations for Soft Body Adhesion
NASA Astrophysics Data System (ADS)
Sauer, Roger A.
This article gives an overview of adhesive contact for soft bodies and focuses on a general computational framework that is suitable for treating a large class of adhesion problems. The contact formulation is based on a non-linear continuum approach that is capable of describing bodies down to length scales of several nanometers. Several finite element formulations are presented, that introduce various approximations in order to increase the computational efficiency. The approaches are illustrated by several examples throughout the text. These include carbon nanotube interaction, adhesion of spheres, nanoindentation, thin film peeling, gecko adhesion and self-cleaning surface mechanisms.
Adhesion as a weapon in microbial competition
Schluter, Jonas; Nadell, Carey D.; Bassler, Bonnie L.; Foster, Kevin R.
Microbes attach to surfaces and form dense communities known as biofilms, which are central to how microbes live and influence humans. The key defining feature of biofilms is adhesion, whereby cells attach to one another and to surfaces, via attachment factors and extracellular polymers. While adhesion is known to be important for the initial stages of biofilm formation, its function within biofilm communities has not been studied. Here we utilise an individual-based model of microbial groups to study the evolution of adhesion. While adhering to a surface can enable cells to remain in a biofilm, consideration of within-biofilm competition reveals a potential cost to adhesion: immobility. Highly adhesive cells that are resistant to movement risk being buried and starved at the base of the biofilm. However, we find that when growth occurs at the base of a biofilm, adhesion allows cells to capture substratum territory and force less adhesive, competing cells out of the system. This process may be particularly important when cells grow on a host epithelial surface. We test the predictions of our model using the enteric pathogen Vibrio cholerae, which produces an extracellular matrix important for biofilm formation. Flow cell experiments indicate that matrix-secreting cells are highly adhesive and form expanding clusters that remove non-secreting cells from the population, as predicted by our simulations. Our study shows how simple physical properties, such as adhesion, can be critical to understanding evolution and competition within microbial communities. PMID:25290505
Effect of water absorption on pollen adhesion.
Lin, Haisheng; Lizarraga, Leonardo; Bottomley, Lawrence A; Carson Meredith, J
Pollens possess a thin liquid coating, pollenkitt, which plays a major role in adhesion by forming capillary menisci at interfaces. Unfortunately, the influence of humidity on pollenkitt properties and capillary adhesion is unknown. Because humidity varies widely in the environment, the answers have important implications for better understanding plant reproduction, allergy and asthma, and pollen as atmospheric condensation nuclei. Here, pollenkitt-mediated adhesion of sunflower pollen to hydrophilic and hydrophobic surfaces was measured as a function of humidity. The results quantify for the first time the significant water absorption of pollenkitt and the resulting complex dependence of adhesion on humidity. On hydrophilic Si, adhesion increased with increasing RH for pollens with or without pollenkitt, up to 200nN at 70% RH. In contrast, on hydrophobic PS, adhesion of pollenkitt-free pollen is independent of RH. Surprisingly, when pollenkitt was present adhesion forces on hydrophobic PS first increased with RH up to a maximum value at 35% RH (?160nN), and then decreased with further increases in RH. Independent measurement of pollenkitt properties is used with models of capillary adhesion to show that humidity-dependent changes in pollenkitt wetting and viscosity are responsible for this complex adhesion behavior. PMID:25524008
Structural adhesives for missile external protection material
NASA Astrophysics Data System (ADS)
Banta, F. L.; Garzolini, J. A.
Two basic rubber materials are examined as possible external substrate protection materials (EPM) for missiles. The analysis provided a data base for selection of the optimum adhesives which are compatible with the substrate, loads applied and predicted bondline temperatures. Under the test conditions, EA934/NA was found to be the optimum adhesive to bond VAMAC 2273 and/or NBR/EPDM 9969A to aluminum substrate. The optimum adhesive for composite structures was EA956. Both of these adhesives are two-part epoxy systems with a pot life of approximately two hours. Further research is suggested on field repair criteria, nuclear hardness and survivability effects on bondline, and ageing effects.
Chlorinated polyolefins as adhesion promoters for plastics
Lawniczak, J.; Sass, C.; Stoffer, J.O.; Dechent, W.L. [Univ. of Missouri, Rolla, MO (United States)
A new procedure which tests the peel strength of a topcoat applied to a substrate was used to quantitatively determine the effectiveness of a chlorinated pololefin as an adhesion promoter for coatings on plastics. A 4 to 5-fold increase in adhesion resulted for a latex vinyl acrylic topcoat that was applied to polypropylene. Electron Spectroscopy for Chemical Analysis studies showed a topcoat/chlorinated polyolefin adhesive failure for both melamine crosslinked and urethane crosslinked polyester systems on polypropylene. Topcoat/chlorinated polyolefin adhesive failure also occured for both melamine crosslinked and urethane crosslinked polyester systems on thermal plastic olefins. All failure tests were performed at ambient conditions.
Bacterial Adhesion at Synthetic Surfaces
Cunliffe, D.; Smart, C. A.; Alexander, C.; Vulfson, E. N.
A systematic investigation into the effect of surface chemistry on bacterial adhesion was carried out. In particular, a number of physicochemical factors important in defining the surface at the molecular level were assessed for their effect on the adhesion of Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli. The primary experiments involved the grafting of groups varying in hydrophilicity, hydrophobicity, chain length, and chemical functionality onto glass substrates such that the surfaces were homogeneous and densely packed with functional groups. All of the surfaces were found to be chemically well defined, and their measured surface energies varied from 15 to 41 mJ Ę m?2. Protein adsorption experiments were performed with 3H-labelled bovine serum albumin and cytochrome c prior to bacterial attachment studies. Hydrophilic uncharged surfaces showed the greatest resistance to protein adsorption; however, our studies also showed that the effectiveness of poly(ethyleneoxide) (PEO) polymers was not simply a result of its hydrophilicity and molecular weight alone. The adsorption of the two proteins approximately correlated with short-term cell adhesion, and bacterial attachment for L. monocytogenes and E. coli also correlated with the chemistry of the underlying substrate. However, for S. aureus and S. typhimurium a different pattern of attachment occurred, suggesting a dissimilar mechanism of cell attachment, although high-molecular-weight PEO was still the least-cell-adsorbing surface. The implications of this for in vivo attachment of cells suggest that hydrophilic passivating groups may be the best method for preventing cell adsorption to synthetic substrates provided they can be grafted uniformly and in sufficient density at the surface. PMID:10543814
Bacterial adhesion at synthetic surfaces.
Cunliffe, D; Smart, C A; Alexander, C; Vulfson, E N
A systematic investigation into the effect of surface chemistry on bacterial adhesion was carried out. In particular, a number of physicochemical factors important in defining the surface at the molecular level were assessed for their effect on the adhesion of Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli. The primary experiments involved the grafting of groups varying in hydrophilicity, hydrophobicity, chain length, and chemical functionality onto glass substrates such that the surfaces were homogeneous and densely packed with functional groups. All of the surfaces were found to be chemically well defined, and their measured surface energies varied from 15 to 41 mJ. m(-2). Protein adsorption experiments were performed with (3)H-labelled bovine serum albumin and cytochrome c prior to bacterial attachment studies. Hydrophilic uncharged surfaces showed the greatest resistance to protein adsorption; however, our studies also showed that the effectiveness of poly(ethyleneoxide) (PEO) polymers was not simply a result of its hydrophilicity and molecular weight alone. The adsorption of the two proteins approximately correlated with short-term cell adhesion, and bacterial attachment for L. monocytogenes and E. coli also correlated with the chemistry of the underlying substrate. However, for S. aureus and S. typhimurium a different pattern of attachment occurred, suggesting a dissimilar mechanism of cell attachment, although high-molecular-weight PEO was still the least-cell-adsorbing surface. The implications of this for in vivo attachment of cells suggest that hydrophilic passivating groups may be the best method for preventing cell adsorption to synthetic substrates provided they can be grafted uniformly and in sufficient density at the surface. PMID:10543814
A computational model for nanoscale adhesion between deformable solids and its application to gecko adhesion
A computational model for nanoscale adhesion between deformable solids and its application to gecko to the dynamic modeling and simulation of the adhesion and deformation of a gecko seta based on a 3D multiscale to the macroscale. A prominent example is the adhesion mechanism of the gecko, that is also the central focus
The state diagram for cell adhesion under flow: Leukocyte rolling and firm adhesion
Tees, David F.J.
method called ``Adhe- sive Dynamics,'' we have simulated the adhesion of a cell to a surface in flow an unbound blood cell to an adherent one in flow involves a number of steps: initial tethering, transientThe state diagram for cell adhesion under flow: Leukocyte rolling and firm adhesion Kai-Chien Chang
Neutrophil adhesion to endothelial cells and factors affecting adhesion in patients with Behńet's disease
S Sahin; T Ako?lu; H Direskeneli; L S Sen; R Lawrence
OBJECTIVES: To study the in vitro adhesion of polymorphonuclear leucocytes (PMNLs) to endothelial cells in patients with Behńet's disease (BD), and the humoral and cellular factors which may contribute to adhesion. METHODS: A total of 118 patients with BD and 60 healthy controls were studied. In vitro adhesion of chromium-51 labelled normal neutrophils to human umbilical vascular endothelial cell (HUVEC)
Design and fabrication of polymer based dry adhesives inspired by the gecko adhesive system
NASA Astrophysics Data System (ADS)
Jin, Kejia
There has been significant interest in developing dry adhesives mimicking the gecko adhesive system, which offers several advantages compared to conventional pressure sensitive adhesives. Specifically, gecko adhesive pads have anisotropic adhesion properties: the adhesive pads (spatulae) stick strongly when sheared in one direction but are non-adherent when sheared in the opposite direction. This anisotropy property is attributed to the complex topography of the array of fine tilted and curved columnar structures (setae) that bear the spatulae. In this thesis, easy, scalable methods, relying on conventional and unconventional techniques are presented to incorporate tilt in the fabrication of synthetic polymer-based dry adhesives mimicking the gecko adhesive system, which provide anisotropic adhesion properties. In the first part of the study, the anisotropic adhesion and friction properties of samples with various tilt angles to test the validity of a nanoscale tape-peeling model of spatular function are measured. Consistent with the Peel Zone model, samples with lower tilt angles yielded larger adhesion forces. Contact mechanics of the synthetic array were highly anisotropic, consistent with the frictional adhesion model and gecko-like. Based on the original design, a new design of gecko-like dry adhesives was developed which showed superior tribological properties and furthermore showed anisotropic adhesive properties without the need for tilt in the structures. These adhesives can be used to reversibly suspend weights from vertical surfaces (e.g., walls) and, for the first time to our knowledge, horizontal surfaces (e.g., ceilings) by simultaneously and judiciously activating anisotropic friction and adhesion forces. Furthermore, adhesion properties between artificial gecko-inspired dry adhesives and rough substrates with varying roughness are studied. The results suggest that both adhesion and friction forces on a rough substrate depends significantly on the geometrical parameters of the substrate. The results in this study may be helpful for understanding how geckos overcome the influence of natural surface roughness. The novel designs of our dry adhesives open the way for new gecko-like adhesive surfaces and articulation mechanisms that do not rely on intensive nanofabrication.
... tissues or organs inside are normally able to shift around each other. This is because these tissues ... 13. Paine R. Rehabilitation and therapeutic modalities: a language of exercise and rehabilitation. In: DeLee JC, Drez ...
Beta-Chemokine CCL15 Affects the Adhesion and Migration of Hematopoietic Progenitor Cells
Richter, Rudolf; R³ster, Brigitte; Bistrian, Roxana; Forssmann, Wolf-Georg; Seifried, Erhard; Henschler, Reinhard
Summary Background Hematopoietic stem and progenitor cell (HPC) motility is essential for HPC transplantation. The chemokine CXCL12 is key for HPC motility. Further regulators are of interest to improve HPC transplantation and regenerative medicine. Here the impact of the human chemokine CCL15 on HPC motility was investigated. Methods CCL15 plasma concentrations were determined during HPC mobilization in humans. Activity of CCL15 on HPCs was investigated in murine assays, including chemotaxis, adhesion, and CFU-A assays, and competitive repopulation assays. Results During HPC mobilization with granulocyte colony-stimulating factor, blood plasma contains increased concentrations (1.1 ▒ 0.1 ng/ml) of activated CCL15(27¢92) versus 0.4 ▒ 0.1 ng/ml in controls (p = 0.02). CCL15(27¢92) significantly enhanced CXCL12-induced transwell migration of Lin-/Sca1+ HPCs and strengthened shear stress-dependent adhesion to vascular cell adhesion molecule-1 (VCAM-1). CCL15(27¢92) dose-dependently reduced the colony size in CFU-A assays performed with murine bone marrow and Lin-/Sca1+ HPCs. CCL15(27¢92) did not show a direct impact on cell cycle status of HPCs. In murine repopulation assays, pretreatment of bone marrow with CCL15(27¢92) significantly increased competitive repopulation. Conclusion Our results point to a regulation of HPCs by CCL15 by modulating migratory and adhesive properties of HPCs with the potency to improve HPC short-term engraftment in stem cell transplantation. PMID:25960713
Specific phosphorylations transmit signals from leukocyte ?2 to ?1 integrins and regulate adhesion.
Uotila, Liisa M; Jahan, Farhana; Soto Hinojosa, Laura; Melandri, Emiliano; Gr÷nholm, Mikaela; Gahmberg, Carl G
The regulation of integrins expressed on leukocytes must be controlled precisely, and members of different integrin subfamilies have to act in concert to ensure the proper traffic of immune cells to sites of inflammation. The activation of ?2 family integrins through the T cell receptor or by chemokines leads to the inactivation of very late antigen 4. The mechanism(s) of this cross-talk has not been known. We have now elucidated in detail how the signals are transmitted from leukocyte function-associated antigen 1 and show that, after its activation, the signaling involves specific phosphorylations of ?2 integrin followed by interactions with cytoplasmic signaling proteins. This results in loss of ?1 phosphorylation and a decrease in very late antigen 4 binding to its ligand vascular cell adhesion molecule 1. Our results show how a member of one integrin family regulates the activity of another integrin. This is important for the understanding of integrin-mediated processes. PMID:25278023
Characterization of macrophage adhesion molecule
Remold-O'Donnell, E.; Savage, B.
Macrophage adhesion molecule (MAM), an abundant surface molecule which functions in the adhesion and spreading of guinea pig macrophages on surfaces, is characterized as a heterodimer of the trypsin- and plasmin-sensitive glycopeptide gp160 (MAM-..cap alpha..) and the glycopeptide gp93 (MAM-..beta..). The density of MAM molecules is estimated at 630,000 per macrophage on the basis of quantitative binding of /sup 125/I-labeled monoclonal antibody. The glycopeptide subunits display microheterogeneity on isoelectrofocusing; the pI is 5.8-6.3 for gp160 (MAM-..cap alpha..) and 6.4-7.0 for gp93 (MAM-..beta..). A neutrophil gp160, gp93 molecule was shown to be indistinguishable from macrophage MAM on the basis of electrophoresis, isoelectrofocusing, and reactivity with 10 monoclonal antibodies. A related heterodimer of gp93 associated with a larger, antigenically different glycopeptide (gp180, gp93)was identified on circulating lymphocytes. Cumulative properties indicate that MAM is the guinea pig analog of human Mo1 and mouse Mac-1.
Hi-Strength 90 Spray Adhesive Product Description
Rollins, Andrew M.
______________________________________________________________________________ Product Description An industrial grade spray adhesive that is typically used for bonding HPL to wood 3MTM Scotch-WeldTM Hi-Strength 90 Cylinder Spray Adhesive 3MTM Hi-Strength 90 Spray Adhesive (Bulk
Genetics Home Reference: Leukocyte adhesion deficiency type 1
... Genetic disorder catalog Conditions > Leukocyte adhesion deficiency type 1 On this page: Description Genetic changes Inheritance Diagnosis ... April 2014 What is leukocyte adhesion deficiency type 1? Leukocyte adhesion deficiency type 1 is a disorder ...
7 CFR 3201.16 - Adhesive and mastic removers.
Code of Federal Regulations, 2012 CFR
...2012-01-01 2012-01-01 false Adhesive and mastic removers. 3201...Designated Items ¦ 3201.16 Adhesive and mastic removers. (a...and tile mastics as well as adhesive materials, including glue, tape, and gum, from...
49 CFR 587.16 - Adhesive bonding procedure.
Code of Federal Regulations, 2014 CFR
... 2014-10-01 false Adhesive bonding procedure. 587.16 Section...Deformable Barrier ¦ 587.16 Adhesive bonding procedure. Immediately before...these can adversely affect bonding. The adhesive is applied to one...
7 CFR 3201.16 - Adhesive and mastic removers.
Code of Federal Regulations, 2013 CFR
...2013-01-01 2013-01-01 false Adhesive and mastic removers. 3201...Designated Items ¦ 3201.16 Adhesive and mastic removers. (a...and tile mastics as well as adhesive materials, including glue, tape, and gum, from...
7 CFR 2902.16 - Adhesive and mastic removers.
Code of Federal Regulations, 2010 CFR
...2010-01-01 2010-01-01 false Adhesive and mastic removers. 2902...Designated Items ¦ 2902.16 Adhesive and mastic removers. (a...and tile mastics as well as adhesive materials, including glue, tape, and gum, from...
49 CFR 587.16 - Adhesive bonding procedure.
Code of Federal Regulations, 2011 CFR
... 2011-10-01 false Adhesive bonding procedure. 587.16 Section...Deformable Barrier ¦ 587.16 Adhesive bonding procedure. Immediately before...these can adversely affect bonding. The adhesive is applied to one...
7 CFR 3201.16 - Adhesive and mastic removers.
Code of Federal Regulations, 2014 CFR
...2014-01-01 2014-01-01 false Adhesive and mastic removers. 3201...Designated Items ¦ 3201.16 Adhesive and mastic removers. (a...and tile mastics as well as adhesive materials, including glue, tape, and gum, from...
7 CFR 2902.16 - Adhesive and mastic removers.
Code of Federal Regulations, 2011 CFR
...2011-01-01 2011-01-01 false Adhesive and mastic removers. 2902...Designated Items ¦ 2902.16 Adhesive and mastic removers. (a...and tile mastics as well as adhesive materials, including glue, tape, and gum, from...
49 CFR 587.16 - Adhesive bonding procedure.
Code of Federal Regulations, 2013 CFR
... 2013-10-01 false Adhesive bonding procedure. 587.16 Section...Deformable Barrier ¦ 587.16 Adhesive bonding procedure. Immediately before...these can adversely affect bonding. The adhesive is applied to one...
49 CFR 587.16 - Adhesive bonding procedure.
Code of Federal Regulations, 2012 CFR
... 2012-10-01 false Adhesive bonding procedure. 587.16 Section...Deformable Barrier ¦ 587.16 Adhesive bonding procedure. Immediately before...these can adversely affect bonding. The adhesive is applied to one...
49 CFR 587.16 - Adhesive bonding procedure.
Code of Federal Regulations, 2010 CFR
... 2010-10-01 false Adhesive bonding procedure. 587.16 Section...Deformable Barrier ¦ 587.16 Adhesive bonding procedure. Immediately before...these can adversely affect bonding. The adhesive is applied to one...
Expression of Versican V3 by Arterial Smooth Muscle Cells Alters Tumor Growth Factor ? (TGF?)-, Epidermal Growth Factor (EGF)-, and Nuclear Factor ?B (NF?B)-dependent Signaling Pathways, Creating a Microenvironment That Resists Monocyte Adhesion*
Kang, Inkyung; Yoon, Dong Won; Braun, Kathleen R.; Wight, Thomas N.
Monocyte/macrophage accumulation plays a critical role during progression of cardiovascular diseases, such as atherosclerosis. Our previous studies demonstrated that retrovirally mediated expression of the versican V3 splice variant (V3) by arterial smooth muscle cells (ASMCs) decreases monocyte adhesion in vitro and macrophage accumulation in a model of lipid-induced neointimal formation in vivo. We now demonstrate that V3-expressing ASMCs resist monocyte adhesion by altering the composition of the microenvironment surrounding the cells by affecting multiple signaling pathways. Reduction of monocyte adhesion to V3-expressing ASMCs is due to the generation of an extracellular matrix enriched in elastic fibers and depleted in hyaluronan, and reduction of the proinflammatory cell surface vascular cell adhesion molecule 1 (VCAM1). Blocking these changes reverses the protective effect of V3 on monocyte adhesion. The enhanced elastogenesis induced by V3 expression is mediated by TGF? signaling, whereas the reduction in hyaluronan cable formation induced by V3 expression is mediated by the blockade of epidermal growth factor receptor and NF?B activation pathways. In addition, expression of V3 by ASMCs induced a marked decrease in NF?B-responsive proinflammatory cell surface molecules that mediate monocyte adhesion, such as VCAM1. Overall, these results indicate that V3 expression by ASMCs creates a microenvironment resistant to monocyte adhesion via differentially regulating multiple signaling pathways. PMID:24719328
Carotid Intima-Media Thickness and Plasma Asymmetric Dimethylarginine in Mexican Children Exposed to Inorganic Arsenic
Osorio-Yß±ez, Citlalli; Ayllon-Vergara, Julio C.; Aguilar-Madrid, Guadalupe; Arreola-Mendoza, Laura; Hernßndez-Castellanos, Erika; Barrera-Hernßndez, Angel; De Vizcaya-Ruiz, Andrea
Background: Arsenic exposure is a risk factor for atherosclerosis in adults, but there is little information on arsenic and early risk biomarkers for atherosclerosis in children. Carotid intima-media thickness (cIMT) is an indicator of subclinical atherosclerotic burden that has been associated with plasma asymmetric dimethylarginine (ADMA), a predictor of cardiovascular disease risk. Objectives: The aim of this study was to investigate associations of arsenic exposure with cIMT, ADMA, and endothelial adhesion molecules [soluble intercellular cell adhesion molecule-1 (sICAM-1); soluble vascular cell adhesion molecule-1 (sVCAM-1)] in children who had been exposed to environmental inorganic arsenic (iAs). Methods: We conducted a cross-sectional study in 199 children 3¢14 years of age who were residents of Zimapan, Mķxico. We evaluated cIMT using ultrasonography, and plasma lipid profiles by standard methods. We analyzed ADMA, sICAM-1, and sVCAM-1 by ELISA, and measured the concentrations of total speciated arsenic (tAs) in urine using hydride generation cryotrapping atomic absorption spectrometry. Results: In the multiple linear regression model for cIMT, tAs categories were positively associated with cIMT increase. The estimated cIMT diameter was greater in 35- to 70-ng/mL and > 70-ng/mL groups (0.035 mm and 0.058 mm per 1-ng/mL increase in urinary tAs, respectively), compared with the < 35-ng/mL group. In addition to tAs level, plasma ADMA was a significant predictor of cIMT. In the adjusted regression model, cIMT, percent iAs, and plasma sVCAM-1 were significant predictors of ADMA levels (e.g., 0.419-?mol/L increase in ADMA per 1-mm increase in cIMT). Conclusions: Arsenic exposure and plasma ADMA levels were positively associated with cIMT in a population of Mexican children with environmental arsenic exposure through drinking water. Citation: Osorio-Yß±ez C, Ayllon-Vergara JC, Aguilar-Madrid G, Arreola-Mendoza L, Hernßndez-Castellanos E, Barrera-Hernßndez A, De Vizcaya-RuĒz A, Del Razo LM. 2013. Carotid intima-media thickness and plasma asymmetric dimethylarginine in Mexican children exposed to inorganic arsenic. Environ Health Perspect 121:1090¢1096;?http://dx.doi.org/10.1289/ehp.1205994 PMID:23757599
Jones, Matthew C.; Humphries, Jonathan D.; Byron, Adam; Millon-Frķmillon, Angelique; Robertson, Joseph; Paul, Nikki R.; Ng, Daniel H. J.; Askari, Janet A.; Humphries, Martin J.
The integration of cells with their extracellular environment is facilitated by cell surface adhesion receptors, such as integrins, which play important roles in both normal development and the onset of pathologies. Engagement of integrins with their ligands in the extracellular matrix, or counter receptors on other cells, initiates the intracellular assembly of a wide variety of proteins into adhesion complexes such as focal contacts, focal adhesions and fibrillar adhesions. The proteins recruited to these complexes mediate bidirectional signalling across the plasma membrane and as such help to coordinate and / or modulate the multitude of physical or chemical signals to which the cell is subjected. The protocols in this unit describe two approaches for the isolation or enrichment of proteins contained within integrin-associated adhesion complexes together with their local plasma membrane / cytosolic environments from cells in culture. In the first protocol integrin-associated adhesion structures are affinity isolated using microbeads coated with extracellular ligands or antibodies. The second protocol describes the isolation of ventral membrane preparations that are enriched for adhesion complex structures. The protocols permit the determination of adhesion complex components by subsequent downstream analysis by Western blotting or mass spectrometry. PMID:25727331
Low-temperature full wafer adhesive bonding
Frank Niklaus; Peter Enoksson; Edvard Kõlvesten; G÷ran Stemme
We have systematically investigated the influence of different bonding parameters on void formation in a low-temperature adhesive bonding process. As a result of these studies we present guidelines for void free adhesive bonding of 10 cm diameter wafers. We have focused on polymer coatings with layer thicknesses between 1 Ąm and 18 Ąm. The tested polymer materials were benzocyclobutene (BCB)
The role of adhesion in contact fatigue
A. E. Giannakopoulos; T. A. Venkatesh; T. C. Lindley; S. Suresh
By incorporating the effects of interfacial adhesion in the mechanics of rounded contact between two bodies, a new approach is proposed for the quantitative analysis of a wide variety of contact fatigue situations involving cyclic normal, tangential or torsional loading. In this method, conditions of ōstrongö and ōweakö adhesion are identified by relating contact mechanics and fracture mechanics theories. Invoking
Mechanics of hierarchical adhesion structures of geckos
Huajian Gao; Xiang Wang; Haimin Yao; Stanislav Gorb; Eduard Arzt
Geckos (Gekko gecko) have evolved elaborate adhesive structures which allow them to move along vertical walls and ceilings against their body weight. There is strong evidence that the adhesion ability of geckos is due to the van der Waals interaction between a contacting surface and hundreds of thousands of keratinous hairs or setae on the geckoÆs foot; each seta is
Biological adhesion for locomotion: basic principles
B. N. J. Persson
Surface roughness is the main reason why macroscopic solids usually do not adhere to each other with any measurable strength; even a root-mean-square roughness amplitude of approx. 1 ?m is enough to completely remove the adhesion between normal rubber (with an elastic modulus E ? 1 MPa) and a hard nominally flat substrate. Strong adhesion between solids with rough surfaces
Adhesion of polymeric films to pharmaceutical solids
Linda A. Felton; James W. McGinity
The two major forces influencing polymer adhesion include the strength of the interfacial bonds between the polymeric film and the surface of the solid and the internal stresses within the film coating. While good adhesion between the polymer and the substrate is desirable for pharmaceutical products, the small size of the dosage form and the non-uniform surface roughness have created
Tensile and shear strength of adhesives
NASA Technical Reports Server (NTRS)
Stibolt, Kenneth A.
This experiment is conducted in a freshman-level course: Introduction to Engineering Materials. There are no prerequisites for the course although students should have some knowledge of basic algebra. The objectives are to tension and shear test adhesives and to determine the tensile and shear properties of adhesives. Details of equipment of procedure are given.
Wood Structure and Adhesive Bond Strength
Charles R. Frihart
Much of the literature on the bonding of wood and other lignocellulosic materials has concentrated on traditional adhesion theories. This has led to misconceptions because wood is a porous material on both the macroscopic and microscopic levels. A better understanding of wood bonding can be developed by investigating the theories of adhesion and bond strength, taking into consideration the unusual
Glass-ionomer cements as adhesives
A. O. Akinmade; J. W. Nicholson
The literature on the clinical use of glass-ionomer cements is reviewed, and this shows that these materials are successful partly because of the good adhesion they exhibit towards a variety of substrates encountered in dentistry. The reasons for this good adhesion are identified as the good initial wetting of the surfaces met in clinical dentistry, the development of strong chemical
Anisotropic conducting adhesives for electronic assembly
David C. Whalley; Samjid H. Mannan; David J. Williams
Presents some experimental and theoretical results from research exploring the design rules and relevant process parameters in the assembly of electronic components using anisotropic conductive adhesive materials. The experimental configurations studies have geometries representative of flip-chip and micro ball grid array chip scale packaging. Evaluates a range of materials combinations, including (random filled) adhesive materials based on both thermoplastic and
Marine mussel adhesion: biochemistry, mechanisms, and biomimetics
Nandika Bandara; Hongbo Zeng; Jianping Wu
Common blue mussel (Mytilus edulis) is a sessile organism that has unique ability to attach to a wide array of organic and inorganic marine surfaces using its holdfast structures. Strong adhesion to surfaces is essential for mussel survival, movement, and self-defense. Mussel proteins from byssal thread are structural components connecting soft mussel tissues to marine surfaces via an adhesive plaque
Animal Lectins as Cell Adhesion Molecules
H. Kaltner; B. Stierstorfer
Protein-carbohydrate interaction is exploited in cell adhesion mechanisms besides the recognition of peptide motifs. The sugar code thus significantly contributes to the intriguing specificity of cellular selection of binding partners. Focusing on two classes of lectins (selectins and galectins), it is evident that their functionality for mediation of adhesive contacts is becoming increasingly appreciated, as is the integration of this
Surgical glues: are they really adhesive?
Bertrand R. M. Perrin; Michel Dupeux; Piergiorgio Tozzi; Dominique Delay; Philippe Gersbach; Ludwig K. von Segesser
Objective: The aim of this study is to create a standard test to approve the efficacy of a surgical sealant. An industrial test, the bulge-and-blister test, which is very convenient for measuring adhesion energy, is applied to the surgical field to quantify adhesion of bioadhesives. Methods: Samples were composed of two circular layers of equine pericardium glued by the surgical
Cellulose Graft Copolymers for Potential Adhesive Applications
Narayan, Ramani
Chapter 24 Cellulose Graft Copolymers for Potential Adhesive Applications Bonding of Plastics covalent bonds to the graft polymer backbone. The net result of this improved adhesion is a finer Resources Purdue University West Lafayette, IN 47907 Bonding of hydrophobic plastic materials to wood
Adhesive Loose Packings of Small Particles
Wenwei Liu; Shuiqing Li; Adrian Baule; Hernßn A. Makse
We explore adhesive loose packings of dry small spherical particles of micrometer size using 3D discrete-element simulations with adhesive contact mechanics. A dimensionless adhesion parameter ($Ad$) successfully combines the effects of particle velocities, sizes and the work of adhesion, identifying a universal regime of adhesive packings for $Ad>1$. The structural properties of the packings in this regime are well described by an ensemble approach based on a coarse-grained volume function that includes correlations between bulk and contact spheres. Our theoretical and numerical results predict: (i) An equation of state for adhesive loose packings that appears as a continuation from the frictionless random close packing (RCP) point in the jamming phase diagram; (ii) The existence of a maximal loose packing point at the coordination number $Z=2$ and packing fraction $\\phi=1/2^{3}$. Our results highlight that adhesion leads to a universal packing regime at packing fractions much smaller than the random loose packing, which can be described within a statistical mechanical framework. We present a general phase diagram of jammed matter comprising frictionless, frictional, adhesive as well as non-spherical particles, providing a classification of packings in terms of their continuation from the spherical frictionless RCP.
Adhesion hysteresis of silane coated microcantilevers
The authors have developed a new experimental approach for measuring hysteresis in the adhesion between micromachined surfaces. By accurately modeling the deformations in cantilever beams that are subject to combined interfacial adhesion and applied electrostatic forces, they determine adhesion energies for advancing and receding contacts. They draw on this new method to examine adhesion hysteresis for silane coated micromachined structures and found significant hysteresis for surfaces that were exposed to high relative humidity (RH) conditions. Atomic force microscopy studies of these surfaces showed spontaneous formation of agglomerates that they interpreted as silages that have irreversibly transformed from uniform surface layers at low RH to isolated vesicles at high RH. They used contact deformation models to show that the compliance of these vesicles could reasonably account for the adhesion hysteresis that develops at high RH as the surfaces are forced into contact by an externally applied load.
Adhesion of elastomeric impression materials to trays.
Bindra, B; Heath, J R
The tensile and shear adhesive bond strengths of two addition cured silicones (Provil and Express) and a polyether (Impregum) impression material to brass, poly(methylmethacrylate) and visible light-cured (VLC) tray resin were determined. Adhesive application significantly increased the bond strength; Provil and Express adhered most strongly to brass; whilst the Impregum-VLC combination produced the strongest bond. Indeed, VLC resin generated greater adhesion than acrylic resin. Exchanging the adhesives specified for each silicone material generally resulted in higher bond strengths. No correlation was established between speed of separation of the test surfaces and bond strength. For optimum clinical performance, the impression material (adhesive) tray material giving the highest bond strength should be utilized. PMID:9049922
Coating to enhance metal-polymer adhesion
Parthasarathi, A.; Mahulikar, D. [Olin Metals Research Laboratories, New Haven, CT (United States)
An ultra-thin electroplated coating has been developed to enhance adhesion of metals to polymers. The coating was developed for microelectronic packaging applications where it greatly improves adhesion of metal leadframes to plastic molding compounds. Recent tests show that the coating enhances adhesion of different metals to other types of adhesives as well and may thus have wider applicability. Results of adhesion tests with this coating, as well as its other characteristics such as corrosion resistance, are discussed. The coating is a very thin transparent electroplated coating containing zinc and chromium. It has been found to be effective on a variety of metal surfaces including copper alloys, Fe-Ni alloys, Al alloys, stainless steel, silver, nickel, Pd/Ni and Ni-Sn. Contact resistance measurements show that the coating has little or no effect on electrical resistivity.
Controllable adhesion using field-activated fluids
NASA Astrophysics Data System (ADS)
Ewoldt, Randy H.; Tourkine, Piotr; McKinley, Gareth H.; Hosoi, A. E.
We demonstrate that field-responsive magnetorheological fluids can be used for variable-strength controllable adhesion. The adhesive performance is measured experimentally in tensile tests (a.k.a. probe-tack experiments) in which the magnetic field is provided by a cylindrical permanent magnet. Increasing the magnetic field strength induces higher peak adhesive forces. We hypothesize that the adhesion mechanism arises from the shear resistance of a yield stress fluid in a thin gap. This hypothesis is supported by comparing the experimentally measured adhesive performance to the response predicted by a lubrication model for a non-Newtonian fluid with a field-dependent yield stress. The model predictions are in agreement with experimental data up to moderate field strengths. Above a critical magnetic field strength the model over-predicts the experimentally measured values indicating non-ideal conditions such as local fluid dewetting from the surface.
Viscoelastic effects in the adhesion of elastomers
NASA Astrophysics Data System (ADS)
Hung, Wei Jing
Viscoelastic effects in the tear strength and adhesion of elastomers were investigated by: (1) using a viscoelastic data analysis tool, the Williams, Landel, and Ferry (WLF) equation, to understand the tear strength and adhesion of butyl rubber as a function of dwell time and contact temperature; (2) conducting a simple peel test to measure the adhesion of elastomers to filler particles; and (3) using an equation derived from the Johnson-Kendall-Roberts (JKR) theory to calculate the energy required to peel an elastomer strip from a layer of filler particles. The WLF equation was used to form mastercurves of fracture energy of butyl rubber versus effective rate of crack propagation. The peel strength was found to increase continuously over long periods of contact until failure became cohesive within the elastomer layer. At higher temperatures the peel strength increased more rapidly, consistent with the WLF relation governing molecular motion. It is postulated that slow molecular rearrangements occur at the interface, increasing bond strength. Secondly, a simple peel test was used to study the adhesion of three elastomers to filler particles. An interlayer of carbon black particles increased peel strength by up to 300% compared with self-adhesion. Silica particles also increased adhesion, but by a smaller factor. There were significant differences between the different elastomers. Also, the strength of adhesion depended on the degree of crosslinking of the elastomer layers; at higher levels of crosslinking, both self-adhesion and adhesion to particles were reduced. This simple experiment gives an indication of the relative strength of adhesion for different combinations of elastomer and reinforcing filler. Strengths calculated from the hypothesized equation agreed approximately with experimental values.
VLA-4 blockade promotes differential routes into human CNS involving PSGL-1 rolling of T cells and MCAM-adhesion of TH17 cells.
Schneider-Hohendorf, Tilman; Rossaint, Jan; Mohan, Hema; B÷ning, Daniel; Breuer, Johanna; Kuhlmann, Tanja; Gross, Catharina C; Flanagan, Ken; Sorokin, Lydia; Vestweber, Dietmar; Zarbock, Alexander; Schwab, Nicholas; Wiendl, Heinz
The focus of this study is the characterization of human T cell blood-brain barrier migration and corresponding molecular trafficking signatures. We examined peripheral blood and cerebrospinal fluid immune cells from patients under long-term anti-very late antigen-4 (VLA-4)/natalizumab therapy (LTNT) and from CNS specimens. LTNT patients' cerebrospinal fluid T cells exhibited healthy central-/effector-memory ratios, but lacked CD49d and showed enhanced myeloma cell adhesion molecule (MCAM) expression. LTNT led to an increase of PSGL-1 expression on peripheral T cells. Although vascular cell adhesion molecule-1 (VLA-4 receptor) was expressed at all CNS barriers, P-selectin (PSGL-1-receptor) was mainly detected at the choroid plexus. Accordingly, in vitro experiments under physiological flow conditions using primary human endothelial cells and LTNT patients' T cells showed increased PSGL-1-mediated rolling and residual adhesion, even under VLA-4 blockade. Adhesion of MCAM(+)/TH17 cells was not affected by VLA-4 blocking alone, but was abrogated when both VLA-4 and MCAM were inhibited. Consistent with these data, MCAM(+) cells were detected in white matter lesions, and in gray matter of multiple sclerosis patients. Our data indicate that lymphocyte trafficking into the CNS under VLA-4 blockade can occur by using the alternative adhesion molecules, PSGL-1 and MCAM, the latter representing an exclusive pathway for TH17 cells to migrate over the blood-brain barrier. PMID:25135296
Stroke status evoked adhesion molecule genetic alterations in astrocytes isolated from stroke-prone spontaneously hypertensive rats and the apigenin inhibition of their expression.
Yamagata, Kazuo; Kitazawa, Takuya; Shinoda, Masahiro; Tagawa, Chika; Chino, Makoto; Matsufuji, Hiroshi
We examined the possibility that the expression of adhesion molecules is regulated differently in cultured astrocytes from stroke-prone spontaneously hypertensive rats (SHRSP/IZM) rats than in those from Wistar Kyoto rats (WKY/IZM) by tumor necrosis factor-alpha (TNF-alpha) or hypoxia and reoxygenation (H/R) and the inhibitory effects of apigenin. It was found that the expression of vascular cell adhesion molecule-1 (VCAM-1) by TNF-alpha in astrocytes isolated from SHRSP/IZM was increased compared with that in WKY/IZM. The expression of monocyte chemotactic protein-1 (MCP-1) mRNA induced by H/R in SHRSP/IZM astrocytes was increased compared with that in normal oxygen concentrations. Apigenin strongly attenuated TNF-alpha-induced VCAM-1 mRNA and protein expression and suppressed the adhesion of U937 cells and SHRSP/IZM astrocytes. These results suggest that the expression levels of adhesion molecules during H/R affect disease outcome and can drive SHRSP/IZM to stroke. It is suggested that apigenin regulates adhesion molecule expression in reactive astrocytes during ischemia. PMID:20700422
Stroke Status Evoked Adhesion Molecule Genetic Alterations in Astrocytes Isolated from Stroke-Prone Spontaneously Hypertensive Rats and the Apigenin Inhibition of Their Expression
Yamagata, Kazuo; Kitazawa, Takuya; Shinoda, Masahiro; Tagawa, Chika; Chino, Makoto; Matsufuji, Hiroshi
We examined the possibility that the expression of adhesion molecules is regulated differently in cultured astrocytes from stroke-prone spontaneously hypertensive rats (SHRSP/IZM) rats than in those from Wistar Kyoto rats (WKY/IZM) by tumor necrosis factor-alpha (TNF-?) or hypoxia and reoxygenation (H/R) and the inhibitory effects of apigenin. It was found that the expression of vascular cell adhesion molecule-1 (VCAM-1) by TNF-? in astrocytes isolated from SHRSP/IZM was increased compared with that in WKY/IZM. The expression of monocyte chemotactic protein-1 (MCP-1) mRNA induced by H/R in SHRSP/IZM astrocytes was increased compared with that in normal oxygen concentrations. Apigenin strongly attenuated TNF-?-induced VCAM-1 mRNA and protein expression and suppressed the adhesion of U937 cells and SHRSP/IZM astrocytes. These results suggest that the expression levels of adhesion molecules during H/R affect disease outcome and can drive SHRSP/IZM to stroke. It is suggested that apigenin regulates adhesion molecule expression in reactive astrocytes during ischemia. PMID:20700422
Drug exposure in a metastatic human lung adenocarcinoma cell line gives rise to cells with differing adhesion, proliferation, and gene expression: Implications for cancer chemotherapy.
Li, Huiling; He, Jianxing; Zhong, Nanshan; Hoffman, Robert M
The Am1010 cell line was previously established from a metastatic deposit in an arm muscle from a patient with lung adenocarcinoma who had undergone four cycles of chemotherapy with cisplatin and taxol. Am1010 cells were labeled with red fluorescent protein or green fluorescent protein. A total of eight sublines were isolated following inĀvitro exposure to cisplatin or taxol. The sublines differed with regard to their adhesion and proliferation properties, with certain sublines exhibiting an increased proliferation rate and/or decreased surface adhesion. Gene expression assays demonstrated that tenascinĀC; cyclinĀD1; collagen, typeĀ1, ?2; integrinĀ?1; related RAS viral (r?ras) oncogene homologĀ2; platelet?derived growth factor C; and Src homologĀ2 domain containing in the focal adhesion pathway, and intercellular adhesion moleculeĀ1, F11 receptor, claudinĀ7 and cadherinĀ1 in the cell adhesion pathway, varied in expression among the sublines. The results of the present study suggested that drug exposure may alter the aggressiveness and metastatic potential of cancer cells, which has important implications for cancer chemotherapy. PMID:26004767
VLA-4 blockade promotes differential routes into human CNS involving PSGL-1 rolling of T cells and MCAM-adhesion of TH17 cells
Schneider-Hohendorf, Tilman; Rossaint, Jan; Mohan, Hema; B÷ning, Daniel; Breuer, Johanna; Kuhlmann, Tanja; Gross, Catharina C.; Flanagan, Ken; Sorokin, Lydia; Vestweber, Dietmar; Zarbock, Alexander
The focus of this study is the characterization of human T cell blood¢brain barrier migration and corresponding molecular trafficking signatures. We examined peripheral blood and cerebrospinal fluid immune cells from patients under long-term anti¢very late antigen-4 (VLA-4)/natalizumab therapy (LTNT) and from CNS specimens. LTNT patientsÆ cerebrospinal fluid T cells exhibited healthy central-/effector-memory ratios, but lacked CD49d and showed enhanced myeloma cell adhesion molecule (MCAM) expression. LTNT led to an increase of PSGL-1 expression on peripheral T cells. Although vascular cell adhesion molecule-1 (VLA-4 receptor) was expressed at all CNS barriers, P-selectin (PSGL-1-receptor) was mainly detected at the choroid plexus. Accordingly, in vitro experiments under physiological flow conditions using primary human endothelial cells and LTNT patientsÆ T cells showed increased PSGL-1¢mediated rolling and residual adhesion, even under VLA-4 blockade. Adhesion of MCAM+/TH17 cells was not affected by VLA-4 blocking alone, but was abrogated when both VLA-4 and MCAM were inhibited. Consistent with these data, MCAM+ cells were detected in white matter lesions, and in gray matter of multiple sclerosis patients. Our data indicate that lymphocyte trafficking into the CNS under VLA-4 blockade can occur by using the alternative adhesion molecules, PSGL-1 and MCAM, the latter representing an exclusive pathway for TH17 cells to migrate over the blood¢brain barrier. PMID:25135296
Adhesion through single peptide aptamers
Aubin-Tam, Marie-Eve; Appleyard, David C.; Ferrari, Enrico; Garbin, Valeria; Fadiran, Oluwatimilehin O.; Kunkel, Jacquelyn; Lang, Matthew J.
Aptamer and antibody mediated adhesion is central to biological function and valuable in the engineering of ōlab on a chipö devices. Single molecule force spectroscopy using optical tweezers enables direct non-equilibrium measurement of these non-covalent interactions for three peptide aptamers selected for glass, polystyrene, and carbon nanotubes. A comprehensive examination of the strong attachment between anti-fluorescein 4-4-20 and fluorescein was also carried out using the same assay. Bond lifetime, barrier width, and free energy of activation are extracted from unbinding histogram data using three single molecule pulling models. The evaluated aptamers appear to adhere stronger than the fluorescein antibody under no- and low-load conditions, yet weaker than antibodies at loads above ~25pN. Comparison to force spectroscopy data of other biological linkages shows the diversity of load dependent binding and provides insight into linkages used in biological processes and those designed for engineered systems. PMID:20795685
Peritoneal adhesions after laparoscopic gastrointestinal surgery
Mais, Valerio
Although laparoscopy has the potential to reduce peritoneal trauma and post-operative peritoneal adhesion formation, only one randomized controlled trial and a few comparative retrospective clinical studies have addressed this issue. Laparoscopy reduces de novo adhesion formation but has no efficacy in reducing adhesion reformation after adhesiolysis. Moreover, several studies have suggested that the reduction of de novo post-operative adhesions does not seem to have a significant clinical impact. Experimental data in animal models have suggested that CO2 pneumoperitoneum can cause acute peritoneal inflammation during laparoscopy depending on the insufflation pressure and the surgery duration. Broad peritoneal cavity protection by the insufflation of a low-temperature humidified gas mixture of CO2, N2O and O2 seems to represent the best approach for reducing peritoneal inflammation due to pneumoperitoneum. However, these experimental data have not had a significant impact on the modification of laparoscopic instrumentation. In contrast, surgeons should train themselves to perform laparoscopy quickly, and they should complete their learning curves before testing chemical anti-adhesive agents and anti-adhesion barriers. Chemical anti-adhesive agents have the potential to exert broad peritoneal cavity protection against adhesion formation, but when these agents are used alone, the concentrations needed to prevent adhesions are too high and could cause major post-operative side effects. Anti-adhesion barriers have been used mainly in open surgery, but some clinical data from laparoscopic surgeries are already available. Sprays, gels, and fluid barriers are easier to apply in laparoscopic surgery than solid barriers. Results have been encouraging with solid barriers, spray barriers, and gel barriers, but they have been ambiguous with fluid barriers. Moreover, when barriers have been used alone, the maximum protection against adhesion formation has been no greater than 60%. A recent small, randomized clinical trial suggested that the combination of broad peritoneal cavity protection with local application of a barrier could be almost 100% effective in preventing post-operative adhesion formation. Future studies should confirm the efficacy of this global strategy in preventing adhesion formation after laparoscopy by focusing on clinical end points, such as reduced incidences of bowel obstruction and abdominal pain and increased fertility. PMID:24803803
The role of cytokines, adhesion molecules, and chemokines in interleukin-2-induced lymphocytic infiltration in C57BL/6 mice.
Anderson, J A; Lentsch, A B; Hadjiminas, D J; Miller, F N; Martin, A W; Nakagawa, K; Edwards, M J
IL-2 mediates the regression of certain malignancies, but clinical use is limited because of associated toxicities, including parenchymal lymphocytic infiltration with multiple organ failure. Secondarily induced cytokines are important mediators of IL-2 toxicity and IL-2-induced lymphocyte-endothelial adherence and trafficking. The recently discovered C-C chemokines, RANTES (regulated on activation, normal T expressed and secreted) and macrophage inflammatory protein-1alpha, have also been implicated in lymphocytic migration. We hypothesized that IL-2 alters cytokine, C-C chemokine, and adhesion molecule expression in association with parenchymal lymphocytic infiltration. C57BL/6 mice were injected with 3x10(5) IU of IL-2 or 0.1 ml of 5% dextrose intraperitoneally every 8 h for 6 d, then killed. IL-2 induced massive lymphocytic infiltration in the liver and lung and moderate infiltration in the kidney in association with organ edema and dysfunction. Immunostaining showed increased intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression in association with this organ-specific lymphocytic infiltration. Flow cytometry showed increased expression of the corresponding ligands (lymphocyte function-associated antigen-1 and very late antigen-4) on splenocytes. IL-2 increased TNF-alpha mRNA and protein expression in the liver. Organs infiltrated by lymphocytes had increased TNF-alpha mRNA, whereas RANTES mRNA was increased in all organs, regardless of lymphocytic infiltration. IL-2 toxicity involves organ-specific TNF-alpha and RANTES production with increased ICAM-1 and VCAM-1 expression as potential mechanisms facilitating lymphocytic infiltration and organ dysfunction. PMID:8621780
ICAM-1¢activated Src and eNOS signaling increase endothelial cell surface PECAM-1 adhesivity and neutrophil transmigration
Liu, Guoquan; Place, Aaron T.; Chen, Zhenlong; Brovkovych, Viktor M.; Vogel, Stephen M.; Muller, William A.; Skidgel, Randal A.; Malik, Asrar B.
Polymorphonuclear neutrophil (PMN) extravasation requires selectin-mediated tethering, intercellular adhesion molecule-1 (ICAM-1)¢dependent firm adhesion, and platelet/endothelial cell adhesion molecule 1 (PECAM-1)¢mediated transendothelial migration. An important unanswered question is whether ICAM-1¢activated signaling contributes to PMN transmigration mediated by PECAM-1. We tested this concept and the roles of endothelial nitric oxide synthase (eNOS) and Src activated by PMN ligation of ICAM-1 in mediating PECAM-1¢dependent PMN transmigration. We observed that lung PMN infiltration in vivo induced in carrageenan-injected WT mice was significantly reduced in ICAM-1?/? and eNOS?/? mice. Crosslinking WT mouse ICAM-1 expressed in human endothelial cells (ECs), but not the phospho-defective Tyr518Phe ICAM-1 mutant, induced SHP-2¢dependent Src Tyr530 dephosphorylation that resulted in Src activation. ICAM-1 activation also stimulated phosphorylation of Akt (p-Ser473) and eNOS (p-Ser1177), thereby increasing NO production. PMN migration across EC monolayers was abolished in cells expressing the Tyr518Phe ICAM-1 mutant or by pretreatment with either the Src inhibitor PP2 or eNOS inhibitor L-NAME. Importantly, phospho¢ICAM-1 induction of Src signaling induced PECAM-1 Tyr686 phosphorylation and increased EC surface anti¢PECAM-1 mAb-binding activity. These results collectively show that ICAM-1¢activated Src and eNOS signaling sequentially induce PECAM-1¢mediated PMN transendothelial migration. Both Src and eNOS inhibition may be important therapeutic targets to prevent or limit vascular inflammation. PMID:22806890
76 FR 53369 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Adhesives and...
Federal Register 2010, 2011, 2012, 2013, 2014
...For Adhesives and Sealants'' dated 2006 which...manufacture and use of adhesives, sealants, adhesive primers, or sealant primers, in both...the application of adhesives, sealants, adhesive primers, and sealant primers by...
Silencing stromal interaction molecule 1 by RNA interference inhibits the proliferation and migration of endothelial progenitor cells
Kuang, Chun-yan; Yu, Yang [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China)] [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China); Guo, Rui-wei [Department of Cardiology, Kunming General Hospital of Chengdu Military Area, Yunnan 650032 (China)] [Department of Cardiology, Kunming General Hospital of Chengdu Military Area, Yunnan 650032 (China); Qian, De-hui; Wang, Kui; Den, Meng-yang; Shi, Yan-kun [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China)] [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China); Huang, Lan, E-mail: firstname.lastname@example.com [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China)] [Institute of Cardiovascular Diseases of PLA, Xinqiao Hospital, Third Military Medical University, Chongqing 400037 (China)
Research highlights: {yields} STIM1 and TRPC1 are expressed in EPCs. {yields} Knockdown of STIM1 inhibits the proliferation, migration and SOCE of EPCs. {yields} TRPC1-SOC cooperates with STIM1 to mediate the SOCE of EPCs. -- Abstract: Knockdown of stromal interaction molecule 1 (STIM1) significantly suppresses neointima hyperplasia after vascular injury. Endothelial progenitor cells (EPCs) are the major source of cells that respond to endothelium repair and contribute to re-endothelialization by reducing neointima formation after vascular injury. We hypothesized that the effect of STIM1 on neointima hyperplasia inhibition is mediated through its effect on the biological properties of EPCs. In this study, we investigated the effects of STIM1 on the proliferation and migration of EPCs and examined the effect of STIM1 knockdown using cultured rat bone marrow-derived EPCs. STIM1 was expressed in EPCs, and knockdown of STIM1 by adenoviral delivery of small interfering RNA (siRNA) significantly suppressed the proliferation and migration of EPCs. Furthermore, STIM1 knockdown decreased store-operated channel entry 48 h after transfection. Replenishment with recombinant human STIM1 reversed the effects of STIM1 knockdown. Our data suggest that the store-operated transient receptor potential canonical 1 channel is involved in regulating the biological properties of EPCs through STIM1. STIM1 is a potent regulator of cell proliferation and migration in rat EPCs and may play an important role in the biological properties of EPCs.
Adhesion in ceramics and magnetic media
NASA Technical Reports Server (NTRS)
Miyoshi, Kazuhisa
When a ceramic is brought into contact with a metal or a polymeric material such as a magnetic medium, strong bonds form between the materials. For ceramic-to-metal contacts, adhesion and friction are strongly dependent on the ductility of the metals. Hardness of metals plays a much more important role in adhesion and friction than does the surface energy of metals. Adhesion, friction, surface energy, and hardness of a metal are all related to its Young's modulus and shear modulus, which have a marked dependence on the electron configuration of the metal. An increase in shear modulus results in a decrease in area of contact that is greater than the corresponding increase in surface energy (the fond energy) with shear modulus. Consequently, the adhesion and friction decrease with increasing shear modulus. For ceramics in contact with polymeric magnetic tapes, environment is extremely important. For example, a nitrogen environment reduces adhesion and friction when ferrite contacts polymeric tape, whereas a vacuum environment strengthens the ferrite-to-tape adhesion and increases friction. Adhesion and friction are strongly dependent on the particle loading of the tape. An increase in magnetic particle concentration increases the complex modulus of the tape, and a lower real area of contact and lower friction result.
Stuck in traffic: Patterns of powder adhesion.
Nirmal Thyagu, N; Vasilenko, A; Voyiadjis, A; Glasser, B J; Shinbrot, T
The adhesion of fine particles to surfaces is important for applications ranging from drug delivery to fouling of solar cells. In this letter, we show that powder adhesion can occur in unexpected patterns, concentrating particular grain types in some locations and clearing them from others, and we propose a straightforward traffic model that appears to reproduce many of the behaviors seen. The model predicts different patterns depending on inter-particle cohesion, and we find in both experiment and model that adhesion occurs in three distinct stages. PMID:23085956
Method of making thermally removable adhesives
Aubert, James H.
A method of making a thermally-removable adhesive is provided where a bismaleimide compound, a monomeric furan compound, containing an oxirane group an amine curative are mixed together at an elevated temperature of greater than approximately 90.degree. C. to form a homogeneous solution, which, when cooled to less than approximately 70.degree. C., simultaneously initiates a Diels-Alder reaction between the furan and the bismaleimide and a epoxy curing reaction between the amine curative and the oxirane group to form a thermally-removable adhesive. Subsequent heating to a temperature greater than approximately 100.degree. C. causes the adhesive to melt and allows separation of adhered pieces.
Weld bonding of titanium with polyimide adhesives
NASA Technical Reports Server (NTRS)
Vaughan, R. W.; Sheppard, C. H.; Orell, M. K.
A conductive adhesive primer and a capillary flow adhesive were developed for weld bonding titanium alloy joints. Both formulations contained ingredients considered to be non-carcinogenic. Lap-shear joint test specimens and stringer-stiffened panels were weld bonded using a capillary flow process to apply the adhesive. Static property information was generated for weld bonded joints over the temperature range of 219K (-65 F) to 561K (550 F). The capillary flow process was demonstrated to produce weld bonded joints of equal strength to the weld through weld bonding process developed previously.
The development of low temperature curing adhesives
NASA Technical Reports Server (NTRS)
Green, H. E.; Sutherland, J. D.; Hom, J. M.; Sheppard, C. H.
An approach for the development of a practical low temperature (293 K-311 K/68 F-100 F) curing adhesive system based on a family of amide/ester resins was studied and demonstrated. The work was conducted on resin optimization and adhesive compounding studies. An improved preparative method was demonstrated which involved the reaction of an amine-alcohol precursor, in a DMF solution with acid chloride. Experimental studies indicated that an adhesive formulation containing aluminum powder provided the best performance when used in conjunction with a commercial primer.
Adhesive bonding using variable frequency microwave energy
Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)
Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.
Adhesive bonding using variable frequency microwave energy
Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.
Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.
Adhesive bonding using variable frequency microwave energy
Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.
Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.
The effect of an external magnetic force on cell adhesion and proliferation of magnetically labeled mesenchymal stem cells
Background As the strategy for tissue regeneration using mesenchymal stem cells (MSCs) for transplantation, it is necessary that MSCs be accumulated and kept in the target area. To accumulate MSCs effectively, we developed a novel technique for a magnetic targeting system with magnetically labeled MSCs and an external magnetic force. In this study, we examined the effect of an external magnetic force on magnetically labeled MSCs in terms of cell adhesion and proliferation. Methods Magnetically labeled MSCs were plated at the bottom of an insert under the influence of an external magnetic force for 1 hour. Then the inserts were turned upside down for between 1 and 24 hours, and the number of MSCs which had fallen from the membrane was counted. The gene expression of MSCs affected magnetic force was analyzed with microarray. In the control group, the same procedure was done without the external magnetic force. Results At 1 hour after the inserts were turned upside down, the average number of fallen MSCs in the magnetic group was significantly smaller than that in the control group, indicating enhanced cell adhesion. At 24 hours, the average number of fallen MSCs in the magnetic group was also significantly smaller than that in control group. In the magnetic group, integrin alpha2, alpha6, beta3 BP, intercellular adhesion molecule-2 (ICAM-2), platelet/endothelial cell adhesion molecule-1 (PECAM-1) were upregulated. At 1, 2 and 3 weeks after incubation, there was no statistical significant difference in the numbers of MSCs in the magnetic group and control group. Conclusions The results indicate that an external magnetic force for 1 hour enhances cell adhesion of MSCs. Moreover, there is no difference in cell proliferation after using an external magnetic force on magnetically labeled MSCs. PMID:20152029
Palmitate-induced inflammatory pathways in human adipose microvascular endothelial cells promote monocyte adhesion and impair insulin transcytosis.
Pillon, Nicolas J; Azizi, Paymon M; Li, Yujin E; Liu, Jun; Wang, Changsen; Chan, Kenny L; Hopperton, Kathryn E; Bazinet, Richard P; Heit, Bryan; Bilan, Philip J; Lee, Warren L; Klip, Amira
Obesity is associated with inflammation and immune cell recruitment to adipose tissue, muscle and intima of atherosclerotic blood vessels. Obesity and hyperlipidemia are also associated with tissue insulin resistance and can compromise insulin delivery to muscle. The muscle/fat microvascular endothelium mediates insulin delivery and facilitates monocyte transmigration, yet its contribution to the consequences of hyperlipidemia is poorly understood. Using primary endothelial cells from human adipose tissue microvasculature (HAMEC), we investigated the effects of physiological levels of fatty acids on endothelial inflammation and function. Expression of cytokines and adhesion molecules was measured by RT-qPCR. Signaling pathways were evaluated by pharmacological manipulation and immunoblotting. Surface expression of adhesion molecules was determined by immunohistochemistry. THP1 monocyte interaction with HAMEC was measured by cell adhesion and migration across transwells. Insulin transcytosis was measured by total internal reflection fluorescence microscopy. Palmitate, but not palmitoleate, elevated the expression of IL-6, IL-8, TLR2 (Toll-like receptor 2), and intercellular adhesion molecule 1 (ICAM-1). HAMEC had markedly low fatty acid uptake and oxidation, and CD36 inhibition did not reverse the palmitate-induced expression of adhesion molecules, suggesting that inflammation did not arise from palmitate uptake/metabolism. Instead, inhibition of TLR4 to NF-?B signaling blunted palmitate-induced ICAM-1 expression. Importantly, palmitate-induced surface expression of ICAM-1 promoted monocyte binding and transmigration. Conversely, palmitate reduced insulin transcytosis, an effect reversed by TLR4 inhibition. In summary, palmitate activates inflammatory pathways in primary microvascular endothelial cells, impairing insulin transport and increasing monocyte transmigration. This behavior may contribute in vivo to reduced tissue insulin action and enhanced tissue infiltration by immune cells. PMID:25944880
Low-dose aspirin ameliorated hyperlipidemia, adhesion molecule, and chemokine production induced by high-fat diet in Sprague-Dawley rats.
Lin, Hui-Li; Yen, Hsueh-Wei; Hsieh, Su-Ling; An, Li-Mei; Shen, Kuo-Ping
In this study the effects of low-dose aspirin (5?mg/kg) on adhesion molecule and chemokine expression in a hyperlipidemic rat model. Six-week-old Sprague-Dawley (SD) rats were assigned to two control groups receiving either a regular diet or high-fat diet (HFD) and a treatment group fed HFD with 5?mg/kg aspirin for a 10-week period. Compared with the regular diet control group, the HFD control group had higher body weight, lower levels of high-density lipoprotein, higher concentrations of insulin, triglyceride, total cholesterol, and low-density lipoprotein, but no differences in blood glucose and glycated hemoglobin. The prothrombin time (PT) and activated partial thromboplastin time (aPTT) were clearly shortened in the HFD group. That group also had increased expression of intercellular adhesion molecule-1 (ICAM-1), ICAM-2, ICAM-3, vascular cell adhesion molecule (VCAM), platelet endothelial cell adhesion molecule (PECAM) and P-selectin in platelets and vascular adhesion protein-1 in lymphocyte and in aorta increased expressions of ICAM-1, ICAM-2, ICAM-3, VCAM, PECAM, E-selectin, monocyte chemoattractant protein-1 (MCP-1) and CCR2. The HFD rats also had increased PKC?, I?B kinase ? (IKK?), p65, mitogen-activated protein kinases (MAPKs) (p38, c-Jun N-terminal kinases 1, extracellular signal-regulated kinase 1/2), and their phosphorylated forms. Low-dose aspirin improved HFD-induced hyperinsulinemia and hyperlipidemia, recovered PT and aPTT, inhibited upregulation of adhesion molecules and chemokines and reduced expression of PKC?, IKK?, p65, and MAPKs. Low-dose aspirin ameliorates HFD-induced hyperlipidemia and hyperinsulinemia, and prevents HFD-induced expression of adhesion molecules and chemokine formation. PMID:24648214
Dismantlement studies of dismantlable polyurethane adhesive by controlling thermal property
Dongho Kim; Ildoo Chung; Guni Kim
This paper investigated the design of dismantlable polyurethane adhesives and dismantling method. To study the dismantlement property of dismantlable polyurethane adhesive by controlling thermal property, we synthesized polyurethane adhesive with various hard segment contents and used thermally expansive microcapsules. The dismantlement of bonded adherend was caused by the expansion of the adhesive layer with the expansion of the thermally expansive
Role of acid-base interfacial bonding in adhesion
Frederick M. Fowkes
The strength of macroscopic adhesive bonds of polymers is known to be directly proportional to the microscopic exothermic interfacial energy changes of bond formation, as measured by Dupre's 'work of adhesion'. Since the work of adhesion can be very appreciably increased by interfacial acid-base bonding with concomitant increases in adhesive bond strength, it is important to understand the acid-base character
IR Drying of Water-Based Acrylic PSA Adhesives
J. Kajtna; U. Ŗebenik; M. Krajnc; J. Golob
Results of infrared drying of an acrylic microsphere adhesive coating are presented. The effect of IR drying on adhesive coating was analyzed by Fourier transform infrared spectroscopy (FTIR). The adhesion strength was tested by peel adhesion measurement. Drying was experimentally carried out on materials dried to the same moisture extent at different operating conditions. The power of IR heating source,
Jermal G. Chandler; Rishawn L. Brandon; Charles R. Frihart
Adhesive bonding takes place when an adhesive undergoes the conversion from liquid to solid. The liquid properties are needed for the adhesive to fully wet the bonding substance, and the solid properties are needed for the strength required for the union of the final product. The mobility of an adhesive depends heavily on its own physical and chemical properties and
Adhesion-induced receptor segregation and adhesion plaque formation: A model membrane study.
Kloboucek, A; Behrisch, A; Faix, J; Sackmann, E
A model system to study the control of cell adhesion by receptor-mediated specific forces, universal interactions, and membrane elasticity is established. The plasma membrane is mimicked by reconstitution of homophilic receptor proteins into solid supported membranes and, together with lipopolymers, into giant vesicles with the polymers forming an artificial glycocalix. The homophilic cell adhesion molecule contact site A, a lipid-anchored glycoprotein from cells of the slime mold Dictyostelium discoideum, is used as receptor. The success of the reconstitution, the structure and the dynamics of the model membranes are studied by various techniques including film balance techniques, micro fluorescence, fluorescence recovery after photobleaching, electron microscopy, and phase contrast microscopy. The interaction of the functionalized giant vesicles with the supported bilayer is studied by reflection interference contrast microscopy, and the adhesion strength is evaluated quantitatively by a recently developed technique. At low receptor concentrations adhesion-induced receptor segregation in the membranes leads to decomposition of the contact zone between membranes into domains of strong (receptor-mediated) adhesion and regions of weak adhesion while continuous zones of strong adhesion form at high receptor densities. The adhesion strengths (measured in terms of the spreading pressure S) of the various states of adhesion are obtained locally by analysis of the vesicle contour near the contact line in terms of elastic boundary conditions of adhesion: the balance of tensions and moments. The spreading pressure of the weak adhesion zones is S approximately 10(-9) J/m(2) and is determined by the interplay of gravitation and undulation forces whereas the spreading pressure of the tight adhesion domains is of the order S approximately 10(-6) J/m(2). PMID:10512849
Three types of siloxane-based network polymers have been investigated for their surface properties towards potential applications as minimally adhesive coatings. A filled poly(dimethylsiloxane) (PDMS) elastomer, RTV it, has been studied to determine surface weldability and stabil...
Proteomic Analysis of Integrin Adhesion Complexes
NSDL National Science Digital Library
Adam Byron (University of Manchester; Wellcome Trust Centre for Cell-Matrix Research REV)
Integrin receptors regulate cell fate by coupling the binding of extracellular adhesion proteins to the assembly of intracellular cytoskeletal and signaling complexes. A detailed, integrative view of adhesion complexes will provide insight into the molecular mechanisms that control cell morphology, survival, movement, and differentiation. To date, membrane receptor¢associated signaling complexes have been refractory to proteomic analysis because of their inherent lability and inaccessibility. We developed a methodology to isolate ligand-induced integrin adhesion complexes, and we used this technique to analyze the composition of complexes associated with multiple receptor¢ligand pairs and define core and receptor-specific subnetworks. In particular, we identified regulator of chromosome condensation¢2 (RCC2) as a component of fibronectin-activated signaling pathways that regulate directional cell movement. The development of this proteomics pipeline provides the means to investigate the molecular composition and function of various adhesion complexes.
Ins and Outs of Microbial Adhesion
NASA Astrophysics Data System (ADS)
Virji, Mumtaz
Microbial adhesion is generally a complex process, involving multiple adhesins on a single microbe and their respective target receptors on host cells. In some situations, various adhesins of a microbe may co-operate in an apparently hierarchical and sequential manner whereby the first adhesive event triggers the target cell to express receptors for additional microbial adhesins. In other instances, adhesins may act in concert leading to high avidity interactions, often a prelude to cellular invasion and tissue penetration. Mechanisms used to target the host include both lectin-like interactions and protein-protein interactions; the latter are often highly specific for the host or a tissue within the host. This reflective chapter aims to offer a point of view on microbial adhesion by presenting some experiences and thoughts especially related to respiratory pathogens and explore if there can be any future hope of controlling bacterial infections via preventing adhesion or invasion stages of microbial pathogenesis.
Labial Adhesions: A Guide for Parents
... adhesion towards the perineum (the area above the anal opening). Gently apply the cream to the white ... separated with your other hand). Avoid touching the anal opening to keep the area clean. Once the ...
Diverse evolutionary paths to cell adhesion.
Abedin, Monika; King, Nicole
The morphological diversity of animals, fungi, plants, and other multicellular organisms stems from the fact that each lineage acquired multicellularity independently. A prerequisite for each origin of multicellularity was the evolution of mechanisms for stable cell-cell adhesion or attachment. Recent advances in comparative genomics and phylogenetics provide critical insights into the evolutionary foundations of cell adhesion. Reconstructing the evolution of cell junction proteins in animals and their unicellular relatives exemplifies the roles of co-option and innovation. Comparative studies of volvocine algae reveal specific molecular changes that accompanied the evolution of multicellularity in Volvox. Comparisons between animals and Dictyostelium show how commonalities and differences in the biology of unicellular ancestors influenced the evolution of adhesive mechanisms. Understanding the unicellular ancestry of cell adhesion helps illuminate the basic cell biology of multicellular development in modern organisms. PMID:20817460
Molecular dynamics simulation of interfacial adhesion
Yarovsky, I.; Chaffee, A.L. [BHP Research, Mulgrave (Australia)
Chromium salts are often used in the pretreatment stages of steel painting processes in order to improve adhesion at the metal oxide/primer interface. Although well established empirically, the chemical basis for the improved adhesion conferred by chromia is not well understood. A molecular level understanding of this behaviour should provide a foundation for the design of materials offering improved adhesion control. Molecular modelling of adhesion involves simulation and analysis of molecular behaviour at the interface between two interacting phases. The present study concerns behaviour at the boundary between the metal coated steel surface (with or without chromium pretreatment) and an organic primer based on a solid epoxide resin produced from bisphenol A and epichlorohydrin. An epoxy resin oligomer of molecular weight 3750 was used as the model for the primer.
Adhesive properties and kinetic polymerization behavior of resins containing adhesion promoting monomers for precious metals.
Kadoma, Yoshinori
Adhesion promoting monomers -5-(4-vinylbenzyl)-2-thiobarbituric acid (5VS), 9,10-epithiodecyl methacrylate (EP8MA), 9,10-epithiodecyl 4-vinylbenzoate (EP8VB), and 3,4-epithiobutyl 2,2-bis(methacryloyloxymethyl)propionate (EP2BMA)--were added to the MMA liquid of a MMA-PMMA/TBBO resin. Three dental precious metal alloys were butt-jointed together with the MMA-PMMA/TBBO adhesive resin, and tensile bond strength was measured after 2,000 thermocycles in water. Polymerization kinetics of MMA by 2,2'-azobis (isobutyronitrile) at 70 degrees C in the presence of 5VS, EP8MA, EP8VB, or EP2BMA were examined quantitatively using a DSC to clarify the relationship between the adhesive properties of MMA-PMMA/TBBO adhesive resin and the kinetic polymerization behavior thereof. Obtained kinetic parameters indicated that 5VS was not suitable as an adhesive monomer for adhesive resin formulations and that EP2BMA possessed the latent potential as an adhesive monomer. Further, tensile test results revealed the applicability of EP8MA, EP8VB, and EP2BMA as an adhesive monomer component of adhesive resin formulations. PMID:16279723
Design guidelines for hybrid microcircuits; organic adhesives for hybrid microcircuits
NASA Technical Reports Server (NTRS)
Perkins, K. L.; Licari, J. J.
The properties of organic adhesives were studied to acquire an adequate information base to generate a guideline document for the selection of adhesives for use in high reliability hybrid microcircuits. Specific areas covered include: (1) alternate methods for determining the outgassing of cured adhesives; (2) effects of long term aging at 150C on the electrical properties of conductive adhesives; (3) effects of shelf life age on adhesive characteristics; (4) bond strengths of electrically conductive adhesives on thick film gold metallization, (5) a copper filled adhesive; (6) effects of products outgassed from cured adhesives on device electrical parameters; (7) metal migration from electrically conductive adhesives; and (8) ionic content of electrically insulative adhesives. The tests performed during these investigations are described, and the results obtained are discussed in detail.
Interrelationship of Multiple Endothelial Dysfunction Biomarkers with Chronic Kidney Disease
Chen, Jing; Hamm, L. Lee; Mohler, Emile R.; Hudaihed, Alhakam; Arora, Robin; Chen, Chung-Shiuan; Liu, Yanxi; Browne, Grace; Mills, Katherine T.; Kleinpeter, Myra A.; Simon, Eric E.; Rifai, Nader; Klag, Michael J.; He, Jiang
The interrelationship of multiple endothelial biomarkers and chronic kidney disease (CKD) has not been well studied. We measured asymmetric dimethylarginine (ADMA), L-arginine, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), soluble E-selectin (sE-selectin), von Willebrand factor (vWF), flow-mediated dilation (FMD), and nitroglycerin-induced dilation (NID) in 201 patients with CKD and 201 community-based controls without CKD. Multivariable analyses were used to examine the interrelationship of endothelial biomarkers with CKD. The multivariable-adjusted medians (interquartile ranges) were 0.54 (0.40, 0.75) in patients with CKD vs. 0.25 (0.22, 0.27) ?mol /L in controls without CKD (p<0.0001 for group difference) for ADMA; 67.0 (49.6, 86.7) vs. 31.0 (27.7, 34.2) ?mol/L (p<0.0001) for L-arginine; 230.0 (171.6, 278.6) vs. 223.9 (178.0, 270.6) ng/mL (p=0.55) for sICAM-1; 981.7 (782.6, 1216.8) vs. 633.2 (507.8, 764.3) ng/mL (p<0.0001) for sVCAM-1; 47.9 (35.0, 62.5) vs. 37.0 (28.9, 48.0) ng/mL (p=0.01) for sE-selectin; 1320 (1044, 1664) vs. 1083 (756, 1359) mU/mL (p=0.008) for vWF; 5.74 (3.29, 8.72) vs. 8.80 (6.50, 11.39)% (p=0.01) for FMD; and 15.2 (13.5, 16.9) vs. 19.1 (17.2, 21.0)% (p=0.0002) for NID, respectively. In addition, the severity of CKD was positively associated with ADMA, L-arginine, sVCAM-1, sE-selectin, and vWF and inversely associated with FMD and NID. Furthermore, FMD and NID were significantly and inversely correlated with ADMA, L-arginine, sVCAM-1, sE-selectin, and vWF. In conclusion, these data indicate that multiple dysfunctions of the endothelium were present among patients with CKD. Interventional studies are warranted to test the effects of treatment of endothelial dysfunction on CKD. PMID:26132137
Thermodynamics and gelation of dimerizing adhesive spheres
Weist, A.O.; Glandt, E.D. (Department of Chemical Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6393 (United States))
Wertheim's dual density formalism is applied to study the thermodynamics and gelation behavior of dimerizing adhesive spheres. Both the thermodynamic results (critical points and site--site correlation functions) and connectivity results (gelation threshold and site--site connectedness functions) are determined for mixtures of dumbbells and spheres as a function of the fraction {ital x}{sub 1} of spheres forming dumbbells, the bond length, and the degree of adhesiveness.
Relationships between water wettability and ice adhesion.
Meuler, Adam J; Smith, J David; Varanasi, Kripa K; Mabry, Joseph M; McKinley, Gareth H; Cohen, Robert E
Ice formation and accretion may hinder the operation of many systems critical to national infrastructure, including airplanes, power lines, windmills, ships, and telecommunications equipment. Yet despite the pervasiveness of the icing problem, the fundamentals of ice adhesion have received relatively little attention in the scientific literature and it is not widely understood which attributes must be tuned to systematically design "icephobic" surfaces that are resistant to icing. Here we probe the relationships between advancing/receding water contact angles and the strength of ice adhesion to bare steel and twenty-one different test coatings (?200-300 nm thick) applied to the nominally smooth steel discs. Contact angles are measured using a commercially available goniometer, whereas the average strengths of ice adhesion are evaluated with a custom-built laboratory-scale adhesion apparatus. The coatings investigated comprise commercially available polymers and fluorinated polyhedral oligomeric silsesquioxane (fluorodecyl POSS), a low-surface-energy additive known to enhance liquid repellency. Ice adhesion strength correlates strongly with the practical work of adhesion required to remove a liquid water drop from each test surface (i.e., with the quantity [1 + cos ?(rec)]), and the average strength of ice adhesion was reduced by as much as a factor of 4.2 when bare steel discs were coated with fluorodecyl POSS-containing materials. We argue that any further appreciable reduction in ice adhesion strength will require textured surfaces, as no known materials exhibit receding water contact angles on smooth/flat surfaces that are significantly above those reported here (i.e., the values of [1 + cos ?(rec)] reported here have essentially reached a minimum for known materials). PMID:20949900
Ice adhesion on super-hydrophobic surfaces
S. A. Kulinich; M. Farzaneh
In this study, ice adhesion strength on flat hydrophobic and rough super-hydrophobic coatings with similar surface chemistry (based on same fluoropolymer) is compared. Glaze ice, similar to naturally accreted, was prepared on the surfaces by spraying super-cooled water microdroplets at subzero temperature. Ice adhesion was evaluated by spinning the samples at constantly increasing speed until ice delamination occurred. Super-hydrophobic surfaces
Shear adhesion strength of aligned electrospun nanofibers.
Najem, Johnny F; Wong, Shing-Chung; Ji, Guang
Inspiration from nature such as insects' foot hairs motivates scientists to fabricate nanoscale cylindrical solids that allow tens of millions of contact points per unit area with material substrates. In this paper, we present a simple yet robust method for fabricating directionally sensitive shear adhesive laminates. By using aligned electrospun nylon-6, we create dry adhesives, as a succession of our previous work on measuring adhesion energies between two single free-standing electrospun polymer fibers in cross-cylinder geometry, randomly oriented membranes and substrate, and peel forces between aligned fibers and substrate. The synthetic aligned cylindrical solids in this study are electrically insulating and show a maximal Mode II shear adhesion strength of 27 N/cm(2) on a glass slide. This measured value, for the purpose of comparison, is 270% of that reported from gecko feet. The Mode II shear adhesion strength, based on a commonly known "dead-weight" test, is 97-fold greater than the Mode I (normal) adhesion strength of the same. The data indicate a strong shear binding on and easy normal lifting off. Anisotropic adhesion (Mode II/Mode I) is pronounced. The size and surface boundary effects, crystallinity, and bending stiffness of fibers are used to understand these electrospun nanofibers, which vastly differ from otherwise known adhesive technologies. The anisotropic strength distribution is attributed to a decreasing fiber diameter and an optimized laminate thickness, which, in turn, influences the bending stiffness and solid-state "wettability" of points of contact between nanofibers and surface asperities. PMID:25105533
Vascular adhesion protein-1 (VAP-1)
Marko Salmi; Sirpa Jalkanen
In 1980s the leukocyte adhesion molecules and their ligands on the vascular endothelium were thought to explain tissue-selective,\\u000a or even tissue-specific, leukocyte traffic. At the same time it became apparent that vessels in inflamed joints displayed\\u000a binding characteristics clearly distinct from those in peripheral lymph nodes, gut and skin. In search of joint-selective\\u000a endothelial adhesion molecules we therefore isolated vascular
New pressure-sensitive silicone adhesive
NASA Technical Reports Server (NTRS)
Leiffer, J. L.; Stoops, W. E., Jr.; St. Clair, T. L.; Watkins, V. E., Jr.; Kelly, T. P.
Adhesive for high or low temperatures does not stretch severely under load. It is produced by combining intermediate-molecular-weight pressure sensitive adhesive which does not cure with silicone resin that cures with catalyst to rubbery tack-free state. Blend of silicone tackifier and cured rubbery silicone requires no solvents in either atmospheric or vacuum environments. Ratio of ingredients varies for different degrees of tack, creep resistance, and tensile strength.
Processable polyimide adhesive and matrix composite resin
NASA Technical Reports Server (NTRS)
Pratt, J. Richard (inventor); St.clair, Terry L. (inventor); Progar, Donald J. (inventor)
A high temperature polyimide composition prepared by reacting 4,4'-isophthaloyldiphthalic anhydride with metaphenylenediamine is employed to prepare matrix resins, adhesives, films, coatings, moldings, and laminates, especially those showing enhanced flow with retention of mechanical and adhesive properties. It can be used in the aerospace industry, for example, in joining metals to metals or metals to composite structures. One area of application is in the manufacture of lighter and stronger aircraft and spacecraft structures.
Smooth Vertical Surface Climbing With Directional Adhesion
Sangbae Kim; Matthew Spenko; Salomon Trujillo; Barrett Heyneman; Daniel Santos; Mark R. Cutkosky
Stickybot is a bio-inspired robot that climbs smooth vertical surfaces such as glass, plastic and ceramic tile at 4 cm\\/s. The robot employs several design principles adapted from the gecko including a hierarchy of compliant structures, directional adhesion, and control of tangential contact forces to achieve control of adhesion. We describe the design and fabrication methods used to created under-actuated,
Bacterial adhesion on PEG modified polyurethane surfaces
Ki Dong Park; Young Soo Kim; Dong Keun Han; Young Ha Kim; Eun Hee Bae Lee; Hwal Suh; Kyu Suk Choi
Polyurethane surface was modified with poly(ethylene glycol) (mol. wt. 1000, PEG1k) carrying terminal hydroxyl, amino and sulfonate groups, poly(ethylene glucol) (mol. wt. 3350, PEG3.4k) and PEG3.4k-Heparin, respectively. These surfaces were investigatted for bacterial adhesion using S. epidermidis and E. coli in tryptic soya broth (TSB), brain heart infusion (BHI), and human plasma. All PEG modified surfaces reduced bacterial adhesion significantly
Cryogenic adhesives and sealants: Abstracted publications
NASA Technical Reports Server (NTRS)
Williamson, F. R.; Olien, N. A.
Abstracts of primary documents containing original experimental data on the properties of adhesives and sealants at cryogenic temperatures are presented. The most important references mentioned in each document are cited. In addition, a brief annotation is given for documents considered secondary in nature, such as republications or variations of original reports, progress reports leading to final reports included as primary documents, and experimental data on adhesive properties at temperatures between about 130 K and room temperature.
Adhesion of algal cells to surfaces.
Ozkan, Altan; Berberoglu, Halil
This paper reports the cell-substratum interactions of planktonic (Chlorella vulgaris) and benthic (Botryococcus sudeticus) freshwater green algae with hydrophilic (glass) and hydrophobic (indium tin oxide) substrata to determine the critical parameters controlling the adhesion of algal cells to surfaces. The surface properties of the algae and substrata were quantified by measuring contact angle, electrophoretic mobility, and streaming potential. Using these data, the cell-substratum interactions were modeled using thermodynamic, DLVO, and XDLVO approaches. Finally, the rate of attachment and the strength of adhesion of the algal cells were quantified using a parallel-plate flow chamber. The results indicated that (1) acid-base interactions played a critical role in the adhesion of algae, (2) the hydrophobic alga attached at a higher density and with a higher strength of adhesion on both substrata, and (3) the XDLVO model was the most accurate in predicting the density of cells and their strength of adhesion. These results can be used to select substrata to promote/inhibit the adhesion of algal cells to surfaces. PMID:23597189
Single-molecule mechanics of mussel adhesion
NASA Astrophysics Data System (ADS)
Lee, Haeshin; Scherer, Norbert F.; Messersmith, Phillip B.
The glue proteins secreted by marine mussels bind strongly to virtually all inorganic and organic surfaces in aqueous environments in which most adhesives function poorly. Studies of these functionally unique proteins have revealed the presence of the unusual amino acid 3,4-dihydroxy-L-phenylalanine (dopa), which is formed by posttranslational modification of tyrosine. However, the detailed binding mechanisms of dopa remain unknown, and the chemical basis for mussels' ability to adhere to both inorganic and organic surfaces has never been fully explained. Herein, we report a single-molecule study of the substrate and oxidation-dependent adhesive properties of dopa. Atomic force microscopy (AFM) measurements of a single dopa residue contacting a wet metal oxide surface reveal a surprisingly high strength yet fully reversible, noncovalent interaction. The magnitude of the bond dissociation energy as well as the inability to observe this interaction with tyrosine suggests that dopa is critical to adhesion and that the binding mechanism is not hydrogen bond formation. Oxidation of dopa, as occurs during curing of the secreted mussel glue, dramatically reduces the strength of the interaction to metal oxide but results in high strength irreversible covalent bond formation to an organic surface. A new picture of the interfacial adhesive role of dopa emerges from these studies, in which dopa exploits a remarkable combination of high strength and chemical multifunctionality to accomplish adhesion to substrates of widely varying composition from organic to metallic. 3,4-dihydroxylphenylalanine | atomic force microscopy | mussel adhesive protein
TNF-? increases endothelial progenitor cell adhesion to the endothelium by increasing bond expression and affinity.
Prisco, Anthony R; Prisco, Michael R; Carlson, Brian E; Greene, Andrew S
Endothelial progenitor cells (EPCs) are a rare population of cells that participate in angiogenesis. To effectively use EPCs for regenerative therapy, the mechanisms by which they participate in tissue repair must be elucidated. This study focused on the process by which activated EPCs bind to a target tissue. It has been demonstrated that EPCs can bind to endothelial cells (ECs) through the tumore necrosis factor-? (TNF-?)-regulated vascular cell adhesion molecule 1/very-late antigen 4 (VLA4) interaction. VLA4 can bind in a high or low affinity state, a process that is difficult to experimentally isolate from bond expression upregulation. To separate these processes, a new parallel plate flow chamber was built, a detachment assay was developed, and a mathematical model was created that was designed to analyze the detachment assay results. The mathematical model was developed to predict the relative expression of EPC/EC bonds made for a given bond affinity distribution. EPCs treated with TNF-?/vehicle were allowed to bind to TNF-?/vehicle-treated ECs in vitro. Bound cells were subjected to laminar flow, and the cellular adherence was quantified as a function of shear stress. Experimental data were fit to the mathematical model using changes in bond expression or affinity as the only free parameter. It was found that TNF-? treatment of ECs increased adhesion through bond upregulation, whereas TNF-? treatment of EPCs increased adhesion by increasing bond affinity. These data suggest that injured tissue could potentially increase recruitment of EPCs for tissue regeneration via the secretion of TNF-?. PMID:25539711
Dynamic Contact Model Based on Meniscus Adhesion For Wet Bio-Adhesive Pads: Simulation Experiments
Xiangjun Zhang; Xiong Yi; S. I.-U. Ahmed; Michael Kosinskiy; Yonghe Liu; J. A. Schaefer
Many insects, such as flies, ants, and bugs, and some animals, such as tree frogs, have proven able to run up and down on smooth vertical surfaces using their specialized pads via a wet adhesive mechanism. Although many meniscus adhesion models were proposed to reveal the origin of the interfacial force, few studies have investigated the dynamic contact between this
Wet adhesion with application to tree frog adhesive toe pads and tires
B N J Persson
Strong adhesion between solids with rough surfaces is only possible if at least one of the solids is elastically very soft. Some lizards and spiders are able to adhere (dry adhesion) and move on very rough vertical surfaces due to very compliant surface layers on their attachment pads. Flies, bugs, grasshoppers and tree frogs have less compliant pad surface layers,
Direct observation of microcavitation in underwater adhesion of mushroom-shaped adhesive microstructure
Kovalev, Alexander E; Gorb, Stanislav N
Summary In this work we report on experiments aimed at testing the cavitation hypothesis [Varenberg, M.; Gorb, S. J. R. Soc., Interface 2008, 5, 383¢385] proposed to explain the strong underwater adhesion of mushroom-shaped adhesive microstructures (MSAMSs). For this purpose, we measured the pull-off forces of individual MSAMSs by detaching them from a glass substrate under different wetting conditions and simultaneously video recording the detachment behavior at very high temporal resolution (54,000¢100,000 fps). Although microcavitation was observed during the detachment of individual MSAMSs, which was a consequence of water inclusions present at the glass¢MSAMS contact interface subjected to negative pressure (tension), the pull-off forces were consistently lower, around 50%, of those measured under ambient conditions. This result supports the assumption that the recently observed strong underwater adhesion of MSAMS is due to an air layer between individual MSAMSs [Kizilkan, E.; Heepe, L.; Gorb, S. N. Underwater adhesion of mushroom-shaped adhesive microstructure: An air-entrapment effect. In Biological and biomimetic adhesives: Challenges and opportunities; Santos, R.; Aldred, N.; Gorb, S. N.; Flammang, P., Eds.; The Royal Society of Chemistry: Cambridge, U.K., 2013; pp 65¢71] rather than by cavitation. These results obtained due to the high-speed visualisation of the contact behavior at nanoscale-confined interfaces allow for a microscopic understanding of the underwater adhesion of MSAMSs and may aid in further development of artificial adhesive microstructures for applications in predominantly liquid environments. PMID:24991528
Polymer adhesion at surfaces: biological adhesive proteins and their synthetic mimics
Phillip Messersmith
Mussels are famous for their ability to permanently adhere to a wide variety of wet surfaces, such as rocks, metal and polymer ship hulls, and wood structures. They accomplish this through specialized proteins collectively referred to as mussel adhesive proteins (MAPs). The biophysical aspects of MAP adhesion is being revealed through the use of single molecule force measurements. The results
Influence of adhesion molecule expression by human brain microvessel endothelium on cancer cell adhesion
John Brayton; Zhu Qing; Michael N Hart; John C VanGilder; Zsuzsa Fabry
Cultures of endothelial (En) cells derived from human brain microvessels were established in order to characterize adhesion molecule expression and to assay the adhesion properties of neoplastic cell lines to monolayers of En cells. Low constitutive expression of ?1 integrin (CD29), and ICAM-2 (CD102) was detected on human brain microvessel En cells. The ?1 chain of the VLA integrin family,
Neurosurgical patties: adhesion and damage mitigation.
Stratton-Powell, Ashley A; Anderson, Ian A; Timothy, Jake; Kapur, Nikil; Culmer, Peter
OBJECT Neurosurgical patties are textile pads used during most neurosurgical operations to protect tissues, manage the fluid environment, control hemostasis, and aid tissue manipulation. Recent research has suggested that, contrary to their aim, patties adhere to brain tissue and cause damage during removal. This study aimed to characterize and quantify the degree of and consequences resulting from adhesion between neurosurgical patties and brain tissue. METHODS Using a customized peel apparatus, the authors performed 90░ peel tests on 5 patty products: Policot, Telfa, Americot, Delicot, and Ray-Cot (n = 247) from American Surgical Company. They tested 4 conditions: wet patty on glass (control), wet patty on wet brain peeled at 5 mm/sec (wet), dry patty on wet brain peeled at 5 mm/sec (dry), and wet patty on wet brain peeled at 20 mm/sec (speed). The interaction between patty and tissue was analyzed using peel-force traces and pre-peel histological analysis. RESULTS Adhesion strength differed between patty products (p < 0.001) and conditions (p < 0.001). Adhesion strength was greatest for Delicot patties under wet (2.22 mN/mm) and dry (9.88 mN/mm) conditions. For all patties, damage at the patty-tissue interface was proportional to the degree of fiber contact. When patties were irrigated, mechanical adhesion was reduced by up to 550% compared with dry usage. CONCLUSIONS For all patty products, mechanical (destructive) and liquid-mediated (nondestructive) adhesion caused damage to neural tissue. The greatest adhesion occurred with Delicot patties. To mitigate patty adhesion and neural tissue damage, surgeons should consider regular irrigation to be essential during neurosurgical procedures. PMID:25699413
Photoreversible surfaces to regulate cell adhesion.
Goulet-Hanssens, Alexis; Lai Wing Sun, Karen; Kennedy, Timothy E; Barrett, Christopher J
We report the development of a photoreversible cell culture substrate. We demonstrate the capacity to modify the adhesivity of the substrate using light, altering its capacity to support cell growth. Polyelectrolyte multilayers (PEMs) were used to produce tunable substrates of different thickness and matrix stiffness, which have different intrinsic capacities to support cell adhesion and survival. Surfaces were top-coated with a poly(acrylic acid)-poly(allylamine hydrochloride) polyelectrolyte bilayer functionalized with a small fraction (<1%) of an azobenzene-based photoswitchable sidegroup, which included the cell-adhesive three-amino-acid peptide RGD. Irradiation with light-induced geometric switching of the azo bond, resulting in changes to RGD exposure and consequently to cell adhesion and survival, was investigated on a variety of surfaces of different thickness and stiffness. Substrate stiffness, as modified by the thickness, had a significant influence on the adhesion of NIH 3T3 cells, consistent with previous studies. However, by disrupting the isomerization state of the azobenzene-linked RGD and exposing it to the surface, cell adhesion and survival could be enhanced up to 40% when the positioning of the RGD peptide was manipulated on the softest substrates. These findings identify permissive, yet less-than-optimal, cell culture substrate conditions that can be substantially enhanced using noninvasive modification of the substrate triggered by light. Indeed, where cell adhesion was tuned to be suboptimal under baseline conditions, the light-induced triggers displayed the most enhanced effect, and identification of this 'Goldilocks zone' was key to enabling light triggering. PMID:22913295
Adhesion of latex films. Influence of surfactants
Charmeau, J.Y. [Ecole Superieure de Plasturgie, Bellignat (France); Kientz, E. [PPG France, Saultain (France); Holl, Y. [CNRS and Univ. of Strasbourg (France)
In the applications of film forming latexes in paint, paper, coating, adhesive, textile industries, one of the most important property of latex films is adhesion onto a support. From the point of view of adhesion, latex films have two specificities. The first one arises from the particular structure of the film which is usually not homogeneous but retains to a certain extent the memory of the particles it was made from. These structure effects are clearly apparent when one compares mechanical or adhesion properties of pure latex films and of films of the same polymers but prepared from a solution. Latex films show higher Young`s moduli and lower adhesion properties than solution films. The second specificity of latex films comes from the presence of the surfactant which was used in the synthesis and as stabilizer for the latex. Most industrial latexes contain low amounts of surfactant, typically in the range 0.1 to 2-3 wt%. However, being usually incompatible with the polymer, the surfactant is not homogeneously distributed in the film. It tends to segregate towards the film-air or film-support interfaces or to form domains in the bulk of the film. Distribution of surfactants in latex films has been studied by several authors. The influence of the surfactant on adhesion, as well as on other properties, is thus potentially very important. This article presents the results of the authors investigation of surfactant effects on adhesion properties of latex films. To the authors knowledge, there is no other example, in the open literature, of this kind of study.
Cell Adhesion Strength Is Controlled by Intermolecular Spacing of Adhesion Receptors
Selhuber-Unkel, C.; Erdmann, T.; L¾pez-GarcĒa, M.; Kessler, H.; Schwarz, U.S.; Spatz, J.P.
Abstract Spatial patterning of biochemical cues on the micro- and nanometer scale controls numerous cellular processes such as spreading, adhesion, migration, and proliferation. Using force microscopy we show that the lateral spacing of individual integrin receptor-ligand bonds determines the strength of cell adhesion. For spacings ?90 nm, focal contact formation was inhibited and the detachment forces as well as the stiffness of the cell body were significantly decreased compared to spacings ?50 nm. Analyzing cell detachment at the subcellular level revealed that rupture forces of focal contacts increase with loading rate as predicted by a theoretical model for adhesion clusters. Furthermore, we show that the weak link between the intra- and extracellular space is at the intracellular side of a focal contact. Our results show that cells can amplify small differences in adhesive cues to large differences in cell adhesion strength. PMID:20159150
Identification of a high-mannose ICAM-1 glycoform: effects of ICAM-1 hypoglycosylation on monocyte adhesion and outside in signaling.
Scott, David W; Dunn, Taylor S; Ballestas, Mary E; Litovsky, Silvio H; Patel, Rakesh P
Endothelial adhesion molecules are critical effectors of inflammation ensuring coordinated interactions that allow leukocytes to home to sites of injury. These adhesion molecules are often extensively modified posttranslationaly by the addition of N-glycans, but if, or how, these modifications contribute to the protein function remains poorly understood. Herein we show that activated endothelial cells express two distinct N-glycoforms of intercellular adhesion molecule 1 (ICAM-1) that comprise a complex N-glycoform with ?-2,6 sialic acid present at relatively high levels and a second, less abundant and previously undescribed high-mannose glycoform (HM-ICAM-1). This novel HM-ICAM-1 glycoform was also detected in human coronary artery specimens and moreover appeared to be the dominant glycoform in vivo. Production of exclusively HM-ICAM-1 in cells by ?-mannosidase inhibition increased monocyte rolling and adhesion compared with mature ICAM-1 consistent with high-mannose epitopes providing leukocyte ligands. Cross-linking of ICAM-1 transmits outside-in signals that affect endothelial permeability and survival. Interestingly, cell signaling (assessed using ERK, VE-cadherin, and Akt phosphorylation) was maintained after cross-linking of HM-ICAM-1 compared with mature ICAM-1; however, interactions with the actin cytoskeleton were lost with HM-ICAM-1. These findings suggest that specific ICAM-1 N-glycoforms modulate distinct aspects of the inflammatory response and identify HM-ICAM-1 as a new therapeutic target for controlling leukocyte trafficking and endothelial inflammation. PMID:23703526
Identification of a high-mannose ICAM-1 glycoform: effects of ICAM-1 hypoglycosylation on monocyte adhesion and outside in signaling
Scott, David W.; Dunn, Taylor S.; Ballestas, Mary E.; Litovsky, Silvio H.
Endothelial adhesion molecules are critical effectors of inflammation ensuring coordinated interactions that allow leukocytes to home to sites of injury. These adhesion molecules are often extensively modified posttranslationaly by the addition of N-glycans, but if, or how, these modifications contribute to the protein function remains poorly understood. Herein we show that activated endothelial cells express two distinct N-glycoforms of intercellular adhesion molecule 1 (ICAM-1) that comprise a complex N-glycoform with ?-2,6 sialic acid present at relatively high levels and a second, less abundant and previously undescribed high-mannose glycoform (HM-ICAM-1). This novel HM-ICAM-1 glycoform was also detected in human coronary artery specimens and moreover appeared to be the dominant glycoform in vivo. Production of exclusively HM-ICAM-1 in cells by ?-mannosidase inhibition increased monocyte rolling and adhesion compared with mature ICAM-1 consistent with high-mannose epitopes providing leukocyte ligands. Cross-linking of ICAM-1 transmits outside-in signals that affect endothelial permeability and survival. Interestingly, cell signaling (assessed using ERK, VE-cadherin, and Akt phosphorylation) was maintained after cross-linking of HM-ICAM-1 compared with mature ICAM-1; however, interactions with the actin cytoskeleton were lost with HM-ICAM-1. These findings suggest that specific ICAM-1 N-glycoforms modulate distinct aspects of the inflammatory response and identify HM-ICAM-1 as a new therapeutic target for controlling leukocyte trafficking and endothelial inflammation. PMID:23703526
Human climbing with efficiently scaled gecko-inspired dry adhesives.
Hawkes, Elliot W; Eason, Eric V; Christensen, David L; Cutkosky, Mark R
Since the discovery of the mechanism of adhesion in geckos, many synthetic dry adhesives have been developed with desirable gecko-like properties such as reusability, directionality, self-cleaning ability, rough surface adhesion and high adhesive stress. However, fully exploiting these adhesives in practical applications at different length scales requires efficient scaling (i.e. with little loss in adhesion as area grows). Just as natural gecko adhesives have been used as a benchmark for synthetic materials, so can gecko adhesion systems provide a baseline for scaling efficiency. In the tokay gecko (Gekko gecko), a scaling power law has been reported relating the maximum shear stress ?max to the area A: ?max ? A(-1/4). We present a mechanical concept which improves upon the gecko's non-uniform load-sharing and results in a nearly even load distribution over multiple patches of gecko-inspired adhesive. We created a synthetic adhesion system incorporating this concept which shows efficient scaling across four orders of magnitude of area, yielding an improved scaling power law: ?max ? A(-1/50). Furthermore, we found that the synthetic adhesion system does not fail catastrophically when a simulated failure is induced on a portion of the adhesive. In a practical demonstration, the synthetic adhesion system enabled a 70 kg human to climb vertical glass with 140 cm(2) of adhesive per hand. PMID:25411404
Characteristics of the adhesive determinants of Lactobacillus fermentum 104.
Henriksson, A; Szewzyk, R; Conway, P L
The adhesion of Lactobacillus fermentum 104-R and the variant strain 104-S to porcine gastric squamous epithelium was investigated. An epithelium-specific adhesion was detected for strain 104-S; however, strain 104-R expressed enhanced adhesion capacity to the control surfaces of polystyrene and bovine serum albumin. To characterize the adhesive determinants, the bacterial cells were exposed to various treatments. The adhesion pattern of bacterial cells in buffers of pH values ranging from 2 to 7 was determined. The adhesion of strain 104-S to epithelium was greater in a buffer with a higher pH value. On the other hand, adhesion of strain 104-R to the epithelium was rather unaffected by a change in pH. To the control surfaces of polystyrene or bovine serum albumin, the adhesion of both strains was greatest at pH 2 to 4. Treatment of strain 104-S with metaperiodate did not affect the adhesion to epithelium or polystyrene; however, protease treatment dramatically decreased the adhesion of both strains, thus suggesting that the determinants responsible for the adhesion were proteinaceous. Carbohydrates may be partially involved in the adhesion of 104-R because metaperiodate-treated cells adhered more poorly than control, iodate-treated cells. The adhesion-promoting components are most probably tightly bound to the cell wall, because washing with low-pH buffer (pH 1.2) or sodium dodecyl sulfate had no major effect on the adhesion. PMID:1849714
Adhesive Dynamics Simulation of G-Protein-Mediated Chemokine-Activated Neutrophil Adhesion
Caputo, Kelly E.; Hammer, Daniel A.
Abstract To reach sites of inflammation, a blood-borne neutrophil first rolls over the vessel wall, becoming firmly adherent onĀactivation, and then transmigrates through the endothelium. In this study, we simulate the transition to firm adhesion via chemokine-induced integrin activation. To recreate the transition from rolling to firm adhesion, we use an integrated signaling adhesive dynamics simulation that includes selectin, integrin, and chemokine interactions between the cell and an adhesive substrate. Integrin bonds are of low affinity until activated by chemokine binding to G-protein coupled receptors on the model cell. The signal propagates within the cell through probabilistic diffusion and reaction of the signaling elements to induce the high-affinity integrins required for firm adhesion. This model showed that integrins become progressively active as cells roll and interact with chemokines, leading to a slight slowing before firm adhesion on a timescale similar to that observed in experiments. Increasing the density of chemokine resulted in decreases in the rolling time before stopping, consistent with experimental observations. However, a limit is reached where further increases in chemokine density do not increase adhesion. We found that the timescale for integrin activation correlated with the time to stop. Further, altering parameters within the intracellular signaling cascade that changed the speed of integrin activation, such as effector activation and dissociation rates, correspondingly affected the time to firm adhesion. For all conditions tested, the number of active integrin bonds at the point of firm adhesion was relatively constant. The model predicts that the time to stop would be relatively independent of selectin or integrin density, but strongly dependent onĀthe shear rate because higher shear rates limit the intrinsic activation rate of integrins and require more integrins for adhesion. PMID:19383446
Probing adhesion forces at the molecular scale
Thomas, R.C.; Houston, J.E.; Michalske, T.A. [Sandia National Laboratories, Albuquerque, NM (United States)] [and others
Measurements of adhesion forces at the molecular scale, such as those discussed here, are necessary to understand macroscopic boundary-layer behavior such as adhesion, friction, wear, lubrication, and many other important phenomena. The authors` recent interfacial force microscopy (IFM) studies have provided detailed information about the mechanical response of both self-assembled monolayer (SAM) films and the underlying substrates. In addition, they recently demonstrated that the IFM is useful for studying the chemical nature of such films. In this talk, the authors discuss a new method for studying surface interactions and chemical reactions using the IFM. To quantitatively measure the work of adhesion and bond energies between two organic thin films, they modify both a Au substrate and a Au probe with self-assembling organomercaptan molecules having either the same or different end groups (-CH{sub 3}, -NH{sub 2}, and -COOH), and then analyze the force-versus-displacement curves (force profiles) that result from the approach to contact of the two surfaces. Their results show that the magnitude of the adhesive forces measured between methyl-methyl interactions are in excellent agreement with van der Waals calculations using Lifshitz theory and previous experimentally determined values. Moreover, the measured peak adhesive forces scale as expected for van der Waals, hydrogen-bonding, and acid-base interactions.
Irrigant divalent cation concentrations influence bacterial adhesion
Dass, Clarissa L.; Walsh, Mary F.; Seo, Sue; Shiratsuchi, Hiroe; Craig, David H.; Basson, Marc D.
Background Surgical wounds are frequently contaminated by microbes, but rarely become infected if the bacterial burden is low, and irrigation is used to reduce contamination. Wound fluids are low in calcium and high in magnesium. We hypothesized that manipulating irrigant divalent cation concentrations might influence bacterial adhesion. Methods Staphylococcus aureus, E. coli, and Pseudomonas aeruginosa were stained with fluorescent Calcein AM before plating onto fibroblast monolayers, collagen I, or uncoated bacteriologic plastic. After one hour, wells were washed with HEPES-buffered pH-balanced sterile water without or with 5mM CaCl2, 5mM MgCl2 or 1mM EDTA+EGTA, and the remaining adherent bacteria were assayed fluorometrically. Results Supplementing the irrigation with magnesium or chelators increased but calcium-supplemented irrigation reduced bacterial adhesion to collagen or fibroblasts. Non-specific electrostatic bacterial adhesion to uncoated plastic was unaffected by calcium. Conclusion Bacterial adhesion to mammalian cells and matrix proteins is influenced by divalent cations, and pathogenic bacteria may be adapted to adhere under the low calcium high magnesium conditions in wounds. Although these results await confirmation for other bacteria, and in vivo validation and safety-testing, they suggest that supplementing wound irrigation with 5mM CaCl2 may reduce bacterial adhesion and subsequent wound infection. PMID:19577252
Actin Foci Adhesion of D. discoideum
NASA Astrophysics Data System (ADS)
Flanders, Bret; Paneru, Govind
Amoeboid migration is a fast (10 ?m min-1) integrin-independent mode of migration that is important with D. discoideum, leukocytes, and breast cancer cells. It is poorly understood, but depends on the establishment of adhesive contacts to the substrate where the cell transmits traction forces. In pre-aggregative D. discoideum, a model system for learning about amoeboid migration, these adhesive contacts are discrete complexes that are known as actin-foci. They have an area of ~ 0.5 ?m2 and a lifetime of ~ 20 s. This talk will present measurements of the adhesive character of actin foci that have been obtained using a submicron force transducer that was designed for this purpose. Results on the rupture stresses and lifetimes of individual acting foci under nano-newton level forces will be described in the context of a general theory for cellular adhesion. This theory depends on, essentially, three cellular properties: the membrane-medium surface tension, the number density of adhesion receptors in the membrane, and the receptor-substrate potential energy surface. Therefore, the use of the transducer to determine the surface tension will be presented, as well.
Switchable Adhesion from Bicomponent Polymeric Brushes
NASA Astrophysics Data System (ADS)
Retsos, Haris; Gorodyska, Ganna; Creton, Costantino
We investigated the adhesive and wetting properties of bicomponent polymeric brushes made from end functionalized hydrophilic and hydrophobic polymer chains. The molecular organization of the mixed brush could be varied reversibly by exposure to selective solvents for the two polymers. Adhesive properties were tested by debonding a flat ended probe from soft pressure-sensitive-adhesives (hydrophobic & hydrophilic) and wetting properties were tested by contact angle measurements of water & diiodomethane droplets. The bicomponent brushes were chemically grafted on silicon wafers from end-functionalized chains. Wetting experiments were done directly on the wafers while for adhesion experiments, the wafers were glued on the flat end of the probe prior to the tests. In all cases the organization of the bicomponent brush could be modified reproducibly and reversibly by exposure to selective solvents. Following this strategy we succeeded to create remarkably stable adaptive polymer surfaces that can modify their adhesion and wetting reversibly and also tune them by varying the ratio of the bicomponent brush layer.
Biologically Inspired Mushroom-Shaped Adhesive Microstructures
NASA Astrophysics Data System (ADS)
Heepe, Lars; Gorb, Stanislav N.
Adhesion is a fundamental phenomenon with great importance in technology, in our everyday life, and in nature. In this article, we review physical interactions that resist the separation of two solids in contact. By using examples of biological attachment systems, we summarize and categorize various principles that contribute to the so-called gecko effect. Emphasis is placed on the contact geometry and in particular on the mushroom-shaped geometry, which is observed in long-term biological adhesive systems. Furthermore, we report on artificial model systems with this bio-inspired geometry and demonstrate that surface microstructures with this geometry are promising candidates for technical applications, in which repeatable, reversible, and residue-free adhesion under different environmental conditionsŚsuch as air, fluid, and vacuumŚis required. Various applications in robotic systems and in industrial pick-and-place processes are discussed.
Water based adhesive primers on aluminum substrates
Wightman, J.P.; Mori, S. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)
The number of aluminum alloy bonding applications has been increasing recently in the automobile industry. Primer coating of aluminum substrates is one of the main processes used to promote bond performance. Solvent based organic primers have been used for a long time but environmental regulations now require the substitution of volatile organic compounds (VOC) by alternate materials such as water based adhesive primers. However, the bond strengths obtained with many water based primers are generally lower than for solvent based ones. Water based primers which have some reactive functional groups have been proposed recently but such primers require special treatment. This paper describes a study conducted to optimize bond strength using a water based adhesive as a primer in the adhesive bonding of anodized aluminum.
Evaluation of polyimide films as adhesives
NASA Technical Reports Server (NTRS)
Progar, Donald J.
A commercially available LARC-TPI film and an experimentally prepared film of LARC-TPI with 5 mol pct of 4,4-prime-oxydianiline (ODA), designated as LARC-TPI/ODA, were evaluated as thermoplastic adhesive films for bonding Ti-6Al-4V. Lap shear strength was used to evaluate the materials as adhesives. They were characterized after fracture by determining the glass transition temperature, T(g). The mode of failure is also reported. Thermal exposure at 240 C for 500 and 1000 h and a 72-h water-boil were conducted on lap shear specimens prepared with the two adhesive films. Lap shear tests were conducted at room temperature, 177 C, 204 C, and 232 C before and after exposures.
Metabolically stable cellular adhesion to inert surfaces.
Meldal, Morten; Wu, Boqian; Diness, Frederik; Michael, Roice; Hagel, Grith
The structure of D-amino acid hexapeptides that promote cellular adhesion was determined by screening D-amino acid hexapeptide libraries synthesized on otherwise inert beaded PEGA resin. These new adhesion molecules provide a completely stable cellular environment and facilitate the maintenance of a monolayer of cells on beads for extended periods. The presence of the peptides promotes spreading of the cells on the bead surface. Not surprisingly, the molecules contained a significant number of arginines and/or lysines. However, the exact structure of each peptide is quite important for the degree of adhesion observed, and a motif with three or four basic amino acids spaced within amino acids of intermediate polarity clearly prevailed, for example, k-l/r-h-r-i/v-r-a; this maintains a polar/hydrophobic balance. PMID:21928441
Adhesion assessment of copper thin films
Kriese, M.D.; Gerberich, W.W. [Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Chemical Engineering; Moody, N.R. [Sandia National Labs., Livermore, CA (United States)
Nano-indentation testing has been used to quantitatively assess the adhesion of thin copper films, sputtered to thicknesses of 150 nm to 1500 nm. Copper films of low residual stress were deposited via RF diode cathode sputtering onto SiO{sub 2}/Si substrates. Overlayers of DC magnetron sputtered tungsten, 850 nm thick with high residual stress, were additionally used to provide a driving force for delamination. All films tested exhibited buckle-driven delamination, from which the interfacial toughness was estimated to be 0.2 - 2 J/m{sup 2}, which is comparable to the thermodynamic work of adhesion. The use of an overlayer requires extensions of existing models, but otherwise does not change the interfacial adhesion, allowing measurements of films that would not otherwise delaminate.
Optimizing ultrasonic imaging for adhesively bonded plates
Conboy, Mike; Hart, Scot; Harris-Weiel, David; Meyer, R. L. (Rachel L.); Claytor, T. N. (Thomas N.)
Bonded materials are used in many critical applications, making it important to determine the state of the adhesive during service or aging. It is also of importance, in many cases, to determine if the adhesive has uniformly and completely covered the area to be joined. Through dual transducer scanning, focused and unfocused transducers, and immersion scanning, the uniformity and adherence of a visco-elastic material can be evaluated. In this report, ultrasonic scanning parameters will be optimized experimentally with guidance from simulation tools including Wave 2000 pro and Imagine 3D. We explored optimizing the contrast ratio by varying the interrogation frequency and also by adjusting the distance between the transducer and bond line. An improvement in contrast should also increase the ability to detect differences in compositions and viscosity of the bonded layer. By maximizing the contrast the quality of the visco-elastic bond can be determined, and imperfections detected before adhesive failure.
Water durability of resin bond to precious metal alloys using adhesive resins containing adhesion promoting monomers.
Kadoma, Yoshinori; Kojima, Katsunori
Adhesive resins for precious metals were prepared by adding an adhesion promoting monomer to MMA-PMMA/TBBO resin. Precious metal alloys bonded by the adhesive resin were thermocycled 0, 1,000, 2,000, or 4,000 times in water between 4 and 60 degrees C, and tensile bond strengths were measured. Debonded metal surfaces after the tensile test were analyzed based on an area of cohesive failure. Three-way ANOVA revealed that all the three parameters--adherend, adhesive monomer, and number of thermal cycles--exhibited a significant influence on bond strength. Bond strength significantly decreased with increasing number of thermal cycles except for resin with 9,10-epithiodecyl 4-vinylbenzoate (EP8VB) to Au alloy. Mean bond strength of adhesive resin with 9,10-epithiodecyl methacrylate (EP8MA), EP8VB, or 3,4-epithiobutyl 2,2-bis(methacryloyloxymethyl)propionate (EP2BMA) exceeded 22 MPa after 4,000 thermal cycles. Analysis of debonded surfaces revealed the applicability of EP8MA, EP8VB, and EP2BMA as an adhesive monomer component of adhesive resin formulations. PMID:16445009
Beetle adhesive hairs differ in stiffness and stickiness: in vivo adhesion measurements on individual setae
NASA Astrophysics Data System (ADS)
Bullock, James M. R.; Federle, Walter
Leaf beetles are able to climb on smooth and rough surfaces using arrays of micron-sized adhesive hairs (setae) of varying morphology. We report the first in vivo adhesive force measurements of individual setae in the beetle Gastrophysa viridula, using a smooth polystyrene substrate attached to a glass capillary micro-cantilever. The beetles possess three distinct adhesive pads on each leg which differ in function and setal morphology. Visualisation of pull-offs allowed forces to be measured for each tarsal hair type. Male discoidal hairs adhered with the highest forces (919 ▒ 104 nN, mean ▒ SE), followed by spatulate (582 ▒ 59 nN) and pointed (127 ▒ 19 nN) hairs. Discoidal hairs were stiffer in the normal direction (0.693 ▒ 0.111 N m-1) than spatulate (0.364 ▒ 0.039 N m-1) or pointed (0.192 ▒ 0.044 N m-1) hairs. The greater adhesion on smooth surfaces and the higher stability of discoidal hairs help male beetles to achieve strong adhesion on the elytra of females during copulation. A comparison of pull-off forces measured for single setae and whole pads (arrays) revealed comparable levels of adhesive stress. This suggests that beetles are able to achieve equal load sharing across their adhesive pads so that detachment through peeling is prevented.
Rheological studies on pressure-sensitive silicone adhesives and drug-in-adhesive layers as a means to characterise adhesive performance.
Ho, Kwong Yat; Dodou, Kalliopi
Pressure-sensitive adhesives are viscoelastic polymers used in the formulation of transdermal patches that allow attachment of a patch onto the skin. Established criteria exist that correlate viscoelastic parameters with adhesive performance. In this study, fulfillment of the adhesive performance criteria was examined using two silicone adhesives with different tack properties. The viscoelastic parameters of high and low tack silicone adhesives (BIO-PSA High Tack 7-4302 and BIO-PSA Low Tack 7-4102) were determined and compared with the criteria described by Chu and Dahlquist. Drug-in-adhesive layers were prepared using the high tack adhesive combined with nortriptyline HCl or paracetamol. The effect of drug addition on the viscoelastic properties of the adhesive was examined. The high tack adhesive showed congruence with the established criteria although with a modified range of viscoelastic moduli to that described by Chu. Examination of the low tack adhesive showed that it did not possess the appropriate viscoelastic properties for bonding onto the skin. The addition of the drugs into the high tack adhesive caused a concentration-dependent increase in its cohesive strength. This effect was independent of the physicochemical properties of the drugs tested. PMID:17049768
Molecular mechanics of mussel adhesion proteins
NASA Astrophysics Data System (ADS)
Qin, Zhao; Buehler, Markus J.
Mussel foot protein (mfp), a natural glue produced by marine mussel, is an intriguing material because of its superior ability for adhesion in various environments. For example, a very small amount of this material is sufficient to affix a mussel to a substrate in water, providing structural support under extreme forces caused by the dynamic effects of waves. Towards a more complete understanding of its strength and underwater workability, it is necessary to understand the microscropic mechanisms by which the protein structure interacts with various substrates. However, none of the mussel proteins' structure is known, preventing us from directly using atomistic modeling to probe their structural and mechanical properties. Here we use an advanced molecular sampling technique to identify the molecular structures of two mussel foot proteins (mfp-3 and mfp-5) and use those structures to study their mechanics of adhesion, which is then incorporated into a continuum model. We calculate the adhesion energy of the mussel foot protein on a silica substrate, compute the adhesion strength based on results obtained from molecular modeling, and compare with experimental data. Our results show good agreement with experimental measurements, which validates the multiscale model. We find that the molecular structure of the folded mussel foot protein (ultimately defined by its genetic sequence) favors strong adhesion to substrates, where L-3,4-dihydroxyphenylalanine (or DOPA) protein subunits work in a cooperative manner to enhance adhesion. Our experimental data suggests a peak attachment force of 0.4▒0.1 N, which compares favorably with the prediction from the multiscale model of Fc=0.21-0.33 N. The principles learnt from those results could guide the fabrication of new interfacial materials (e.g. composites) to integrate organic with inorganic surfaces in an effective manner.
Intercellular adhesion mediated by human muscle neural cell adhesion molecule: effects of alternative exon use
Mouse 3T3 fibroblasts were permanently transfected with cDNAs encoding isoforms of the neural cell adhesion molecule (N-CAM) present in human skeletal muscle and brain. Parental and transfected cells were then used in a range of adhesion assays. In the absence of external shear forces, transfection with cDNAs encoding either transmembrane or glycosylphosphatidylinositol (GPI)-linked N-CAM species significantly increased the intercellular adhesiveness of 3T3 cells in suspension. Transfection of a cDNA encoding a secreted N-CAM isoform was without effect on adhesion. Cells transfected with cDNAs containing or lacking the muscle-specific domain 1 sequence, a four-exon group spliced into the muscle but not the brain GPI-linked N-CAM species, were equally adhesive in the assays used. We also demonstrate that N-CAM-mediated intercellular adhesiveness is inhibited by 0.2 mg/ml heparin; but, at higher concentrations, reduced adhesion of parental cells was also seen. Coaggregation of fluorescently labeled and unlabeled cell populations was performed and measured by comparing their distribution within aggregates with distributions that assume nonspecific (random) aggregation. These studies demonstrate that random aggregation occurs between transfected cells expressing the transmembrane and GPI-linked N- CAM species and between parental cells and those expressing the secreted N-CAM isoform. Other combinations of these populations tested exhibited partial adhesive specificity, indicating homophilic binding between surface-bound N-CAM. Thus, the approach exploited here allows for a full analysis of the requirements, characteristics, and specificities of the adhesive behavior of individual N-CAM isoforms. PMID:2532218
HB-EGF Promotes Cell Migration and Adhesion via Focal Adhesion Kinase
Su, Y; Besner, G.E
Background Cell migration and adhesion are essential in intestinal epithelial wound healing and recovery from injury. Focal adhesion kinase (FAK) plays an important role in cell-extra cellular matrix (ECM) signal transduction. We have previously shown that heparin-binding epidermal growth factor-like growth factor (HB-EGF) promotes intestinal epithelial cell (IEC) migration and adhesion in vitro. The current study was designed to determine whether FAK is involved in HB-EGF-induced IEC migration and adhesion. Materials and Methods A scrape wound healing model of rat intestinal epithelial cells (RIE-1 cells) was used to examine the effect of HB-EGF on FAK-dependent cell migration in vitro. Immunofluorescence and Western blot analyses were performed to evaluate the effect of HB-EGF on the expression of phosphorylated FAK (p-FAK). Cell adhesion assays were performed to determine the role of FAK in HB-EGF-induced cell adhesion on fibronectin (FN). Results HB-EGF significantly increased healing after scrape wounding, an effect that was reversed in the presence of a FAK inhibitor (FAK I-14) (both with p<0.05). HB-EGF increased p-FAK expression, and induced p-FAK redistribution and actin reorganization in migrating RIE-1 cells. Cell adhesion and spreading on FN were significantly increased by HB-EGF (p<0.05). FAK I-14 significantly inhibited both intrinsic and HB-EGF-induced cell adhesion and spreading on FN (both with p<0.05). Conclusions FAK phosphorylation and FAK-mediated signal transduction play essential roles in HB-EGF-mediated IEC migration and adhesion. PMID:24703506
Superhydrophobic (low adhesion) and parahydrophobic (high adhesion) surfaces with micro/nanostructures or nanofilaments.
Diouf, Alioune; Darmanin, Thierry; Dieng, Samba Yandķ; Guittard, Frķdķric
Controlling the water adhesion is extremely important for various applications such as for water harvesting. Here, superhydrophobic (low adhesion) and parahydrophobic (high adhesion) substrates are both obtained from hydrophilic polymers. We show in the work that a judicious choice in the monomer structure used for electropolymerization can lead to these two properties. Using a phenyl group, parahydrophobic properties are reached due to the formation of nanofilaments. By contrast, using a naphthalene or a biphenyl group, superhydrophobic properties are obtained due the formation of both micro- and nanostructures. PMID:25965431
Adhesion tilt-tolerance in bio-inspired mushroom-shaped adhesive microstructure
NASA Astrophysics Data System (ADS)
Heepe, Lars; Carbone, Giuseppe; Pierro, Elena; Kovalev, Alexander E.; Gorb, Stanislav N.
We studied experimentally and theoretically the effect of different tilt angles on the adhesion of mushroom-shaped adhesive microstructures. The marginal measured influence of tilting on pull-off forces is quantitatively well confirmed by numerical and theoretical calculations and was shown to be a direct consequence of an optimized stress distribution. In addition, the presence of a joint-like narrowing under the contact elements, as found in some biological attachment systems, was shown to further contribute to the tilt-tolerance. The results obtained allow us to explain the advantage of the widely observed mushroom-shaped contact geometry in nature for long-term and permanent adhesion.
Feeding enriched omega-3 fatty acid beef to rats increases omega-3 fatty acid content of heart and liver membranes and decreases serum vascular cell adhesion molecule-1 and cholesterol levels
Denis M. Medeiros; Meghan Hampton; Kelly Kurtzer; Mardi Parelman; Enas Al-Tamimi; James S. Drouillard
Dietary intake of the long-chain omega-3 fatty acids prevents the development of heart disease. In this study, we evaluated whether feeding beef from cattle fed an omega-3 fatty acid¢enriched diet to rats had health benefits. Cattle raised on a 10% flaxseed diet have high amounts of ?-linolenic acid in their muscle tissue when compared to cattle fed a control diet
76 FR 79537 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Adhesives and Sealants Rule
Federal Register 2010, 2011, 2012, 2013, 2014
...the application of adhesives, sealants, adhesive primers, and sealant primers by providing...the document and sealant begins]. products, including 25 adhesives, 4 adhesive primers, 5 sealants, and 3 sealant...
Strong, reversible underwater adhesion via gecko-inspired hydrophobic fibers.
Soltannia, Babak; Sameoto, Dan
Strong, reversible underwater adhesion using gecko-inspired surfaces is achievable through the use of a hydrophobic structural material and does not require surface modification or suction cup effects for this adhesion to be effective. Increased surface energy can aid in dry adhesion in an air environment but strongly degrades wet adhesion via reduction of interfacial energy underwater. A direct comparison of structurally identical but chemically different mushroom shaped fibers shows that strong, reversible adhesion, even in a fully wetted, stable state, is feasible underwater if the structural material of the fibers is hydrophobic and the mating surface is not strongly hydrophilic. The exact adhesion strength will be a function of the underwater interfacial energy between surfaces and the specific failure modes of individual fibers. This underwater adhesion has been calculated to be potentially greater than the dry adhesion for specific combinations of hydrophobic surfaces. PMID:25454841
Effects of Surface Properties on Adhesion of Protein to BiomaterialsĀ
Feng, Fangzhou
This thesis research investigates the adhesion mechanisms of protein molecules to surfaces of biomaterials. New understanding in such adhesion mechanisms will lead to materials design and surface engineering in order to extend the lifespan...
Diffusion of water vapor into a flowing adhesive sheet
NSDL National Science Digital Library
Powell, Adam C., IV
Calculate flow velocity profile of an adhesive monomer flowing down an inclined plane, and describe the rate and boundary layer structure of mass transfer of water molecules (which might initiate polymerization) into the adhesive.
Study of the adhesion of coal particles during briquetting
Tekenov, Zh.; Dzhamanbaev, A.
The paper presents a method for measuring the forces of adhesion between coal particles during briquetting. Some experimental data are reported illustrating the relationship between the adhesive forces and various factors.
Piezoelectric inkjet printing of medical adhesives and sealants
NASA Astrophysics Data System (ADS)
Boehm, Ryan D.; Gittard, Shaun D.; Byrne, Jacqueline M. H.; Doraiswamy, Anand; Wilker, Jonathan J.; Dunaway, Timothy M.; Crombez, Rene; Shen, Weidian; Lee, Yuan-Shin; Narayan, Roger J.
Piezoelectric inkjet printing is a noncontact process that enables microscale processing of biological materials. In this research summary, the use of piezoelectric inkjet printing for patterning medical adhesives and sealants, including a two-component polyethylene glycol hydrogel-based medical sealant, an N-butyl cyanoacrylate tissue adhesive, and a mussel adhesive protein biological adhesive, is described The effect of Fe(III) on mussel adhesive protein structure was evaluated by means of atomic force microscopy. The ability to process microscale patterns of medical sealants and adhesives will provide an improvement in tissue joining, including enhanced tissue integrity, reduced bond lines, and decreased adhesive toxicity. Piezoelectric inkjet deposition of medical adhesives and sealants may be used in wound closure, fracture fixation, and microscale vascular surgery.
How can we avoid adhesions after laparoscopic surgery?
Tulandi, T
Although fewer develop than after laparotomy, laparoscopic surgery is still associated with adhesion formation. In order to minimize this, nothing replaces good surgical technique. Basic principles of microsurgery, liberal irrigation of the abdominal cavity and instillation of a large amount of Ringer's lactate at the completion of the procedure should be followed. Among adhesion preventing substances, adhesion barriers including expanded polytetrafluoroethylene and regenerated oxidized cellulose are the most effective. Alternatively, a second look laparoscopy to liberate the adhesions can be performed. PMID:9263714
Microtubule-Actin Cross-talk at Focal Adhesions
NSDL National Science Digital Library
Alexander F. Palazzo (Columbia University; Department of Anatomy and Cell Biology REV)
Focal adhesions are dynamic structures in which traction forces are exerted against the substratum during cell migration and are sites for the organization of signaling complexes. Palazzo and Gundersen discuss how focal adhesions may also be the site of cross-talk between the actin-based and microtubule-based cytoskeletons. Microtubules appear to deliver factors that can regulate the formation and dissolution of focal adhesions, whereas focal adhesions contribute to microtubule localization and stability.
Bacterial adhesion and growth on a polymer brush-coating
M. Reza Nejadnik; Henny C. van der Mei; Willem Norde; Henk J. Busscher
Biomaterials-related infections pose serious problems in implant surgery, despite the development of non-adhesive coatings. Non-adhesive coatings, like polymer brush-coatings, have so far only been investigated with respect to preventing initial bacterial adhesion, but never with respect to effects on kinetics of bacterial growth. Here, we compare adhesion and 20h growth of three bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas
Bond strength for adhesive-bonded single-lap joints
L. Tong
Summary Arbitrarily nonlinear stress-strain behaviour in both shear and peel for adhesive are utilised to formulate two coupled nonlinear governing equations for an adhesive-adherend sandwich of single-lap type. For a balanced adhesive-adherend sandwich, the two equations can be integrated, and simple formulas for bond strength are developed for characterising pure shear, peel and mixed failure in adhesive. These formulas define
On the mechanism of adhesion in biological systems
NASA Astrophysics Data System (ADS)
Persson, B. N. J.
I study adhesion relevant to biological systems, e.g., flies, crickets and lizards, where the adhesive microstructures consist of arrays of thin fibers. The effective elastic modulus of the fiber arrays can be very small which is of fundamental importance for adhesion on smooth and rough substrates. I study how the adhesion depend on the substrate roughness amplitude and apply the theoretical results to lizards.
Synergistic control of cell adhesion by integrins and syndecans
Mark R. Morgan; Mark D. Bass; Martin J. Humphries
The ability of cells to adhere to each other and to their surrounding extracellular matrices is essential for a multicellular existence. Adhesion provides physical support for cells, regulates cell positioning and enables microenvironmental sensing. The integrins and the syndecans are two adhesion receptor families that mediate adhesion, but their relative and functional contributions to cell¢extracellular matrix interactions remain obscure. Recent
Orientation angle and the adhesion of single gecko setae
Orientation angle and the adhesion of single gecko setae Ginel C. Hill1,*,, Daniel R. Soto1, Anne M on the adhesion of single gecko setae using dual-axis microelectromechanical systems force sensors and manufacture of gecko-inspired synthetic adhesives with anisotropic properties, an area of substantial recent
Reliability characterisation of Bimodal high temperature stable Isotropic Conductive Adhesives
Wenkai Tao; Si Chen; Xiaohua Liu; Huiwang Cui; Tianan Chen; Johan Liu
Conductive adhesives are generally considered to be one of the strongest candidates for replacement of solder in electronics industry. However, some problems related to the performance have so far limited wider applications of conductive adhesives. One of the major problems is tendency to degrade during temperature and humidity aging. In this paper, two kinds of Isotropic Conductive Adhesives (ICA) with
Fabrication and characterization of hierarchical nanostructured smart adhesion surfaces.
Lee, Hyungoo; Bhushan, Bharat
The mechanics of fibrillar adhesive surfaces of biological systems such as a Lotus leaf and a gecko are widely studied due to their unique surface properties. The Lotus leaf is a model for superhydrophobic surfaces, self-cleaning properties, and low adhesion. Gecko feet have high adhesion due to the high micro/nanofibrillar hierarchical structures. A nanostructured surface may exhibit low adhesion or high adhesion depending upon fibrillar density, and it presents the possibility of realizing eco-friendly surface structures with desirable adhesion. The current research, for the first time uses a patterning technique to fabricate smart adhesion surfaces: single- and two-level hierarchical synthetic adhesive structure surfaces with various fibrillar densities and diameters that allows the observation of either the Lotus or gecko adhesion effects. Contact angles of the fabricated structured samples were measured to characterize their wettability, and contamination experiments were performed to study for self-cleaning ability. A conventional and a glass ball attached to an atomic force microscope (AFM) tip were used to obtain the adhesive forces via force-distance curves to study scale effect. A further increase of the adhesive forces on the samples was achieved by applying an adhesive to the surfaces. PMID:22285098
Evaluation of polyaryl adhesives in elastomer-stainless steel joints
M. Miura; N. Carciello; T. Sugama; L. E. Kukacka
Polyaryl thermoplastic adhesives (polyetheretherketone, PEEK, polyphenylene sulfide PPS, polyphenylethersulfone, PES) were evaluated for ability to bond elastomer to metal for use in geothermal environments. Strength of elastomer-to-metal joints adhesives blends (such as in drill pipe or casing protectors) were determined using peel tests. Parameters involved in making the joints were temperature, time and atmosphere, in addition to type of adhesive.
Reliability and failure mechanism of isotropically conductive adhesives joints
Li Li; J. E. Morris; Johan Liu; Zonghe Lai; L. Ljungkrona; Changhai Li
Three recently developed silver filled isotropic electrically conductive adhesives from different manufacturers were selected for study. This work was focused on the use of isotropically conductive adhesives for joining surface mount devices (SMD) on printed circuit boards for potential solder replacement. The purpose of this study is to evaluate the reliability and failure mechanism of the adhesive joints in humid
Epoxy adhesion strength to ceramic surfaces in commercial optoelectronic assemblies
O. Williams; C. Liu; D. P. Webb; P. Firth
Optoelectronics manufacturers are under continuous pressure for miniaturisation of optoelectronic modules. One route to further miniaturisation is to reduce the spacing between the optical and optoelectronic components in the optical path adhesively mounted to ceramic carriers. Flow control of the adhesives over the ceramic surface is then imperative. Uncontrolled wetting can lead to an excessive adhesive footprint which interferes in
Air Entrapment in the Use of Structural Adhesive Films
Willard D. Bascom; Robert L. Cottington
Air entrapment during the preparation of bonds with structural adhesive films was examined by a microscopy study of glass\\/adhesive\\/glass specimens. It was observed that initially a thin film of air is trapped between the adhesive and adherend and covers over 50 % of the interfacial area. As the specimen is heat cured this air draws up into bubbles that are
What does bonding to modified wood tell us about adhesion?
Christopher G. Hunt; Rishawn Brandon; Rebecca E. Ibach; Charles R. Frihart
Determining adhesive bond performance for chemically modified wood is important not only in relation to its commercial utility but also because this information helps in understanding wood bond durability. Although wood modification is usually used to improve anti-swell efficiency, the modification can alter adhesive bond performance. Generally, modification is expected to diminish adhesion by making the wood surface less polar
Dependance of electric conduction on film thickness of conductive adhesives
Yong Wei; Erol Sancaktar
The effect of film thickness on the conduction behavior of electrically conductive adhesives is presented. For comparison purposes, an analytical relation is developed to predict three dimensional resistivity of particle filled conductive adhesives. This analysis reveals that the adhesive's resistivity depends on parameters, m, representing an average contact number and, Si, representing the average length of conductive paths between the
Mechanical properties of Hysol EA-9394 structural adhesive
Guess, T.R.; Reedy, E.D.; Stavig, M.E.
Dextor`s Hysol EA-9394 is a room temperature curable paste adhesive representative of the adhesives used in wind turbine blade joints. A mechanical testing program has been performed to characterize this adhesive. Tension, compression stress relaxation, flexural, butt tensile, and fracture toughness test results are reported.
Autologous fibrin tissue adhesive in endoscopic sinus surgery
Endoscopic sinus surgery may be complicated by bleeding, formation of synechia, and infection. This study investigated the application of autologous fibrin tissue adhesive during endoscopic sinus surgery in an attempt to avoid packing, to decrease complications, and to improve healing. Fibrin tissue adhesive from pooled human blood is a hemostatic and bacteriostatic agent. Autologous fibrin tissue adhesive avoids the potential
Measuring Interfacial Stiffness of Adhesively-Bonded Wood
Nairn, John A.
1 Measuring Interfacial Stiffness of Adhesively-Bonded Wood Edward A. Le FPInnovations - Engineered Interfacial Stiffness of Adhesively-Bonded Wood Abstract Future Abstract (100 to 150 words) 1. Introduction Adhesive bonds in wood composites have two roles. The first is to hold elements of the composite together
Howat, Colin S. "Chip"
of the adhesive bond between the tire and the rim. In the first four parts (with C. Calvin Jones, Cycling USA. Bond strength using various combinations of types of rims, tires and adhesives are discussed. The `white' glues, Continental and Vittoria Mastik`One, are superior to the `red' glues. Adhesion to carbon
Cure-rate data for silicone adhesive
NASA Technical Reports Server (NTRS)
Clatterbuck, C.; Fisher, A.
Report describes work with concentrations down to 0.07 percent and is useful when applying adhesives in terrestrial and space applications. Cured Silicone retains low-outgassing properties as well as its snap, elongation, and resilience. Tests for hardness of silicone material also showed good results. No gross hysteresis observable on recovery from stretching nor was there any decrease in hardness.
Interface adhesion: effects of plasticity and segregation
A. G. Evans; J. W. Hutchinson; Y. Wei
The adhesion at interfaces between dissimilar materials is strongly affected by both segregation and the extent of plasticity in the adjoining material, particularly when one of these is a metal (or thermoplastic). It will be shown that these interfaces when clean, are generally strong and tough, such that failure occurs in one of the adjoining materials, rather than at the
Hutchinson, John W.
and weaken the interface, especially in combination with ambient moisture. The em- brittlement is obviated either by alloying with elements that ``getter'' the contaminants or by using an ``adhesion layer'' that has essentially the same eect: Cr and Ti are particularly eective gettering elements. Models
Oral bacterial adhesion on amorphous carbon films
A. Almaguer-Flores; R. Olivares-Navarrete; A. Lechuga-Bernal; L. A. Ximķnez-Fyvie; S. E. Rodil
It is now well established that all the different forms of amorphous carbon films are biocompatible and suitable for specific biomedical applications. On the other hand, bacterial adhesion on implant surfaces has also a strong influence on the healing and long-term outcome of biomedical devices and this has not been thoroughly studied for the carbon films. The purpose of this
Microfabricated adhesive mimicking gecko foot-hair
NASA Astrophysics Data System (ADS)
Geim, A. K.; Dubonos, S. V.; Grigorieva, I. V.; Novoselov, K. S.; Zhukov, A. A.; Shapoval, S. Yu.
The amazing climbing ability of geckos has attracted the interest of philosophers and scientists alike for centuries. However, only in the past few years has progress been made in understanding the mechanism behind this ability, which relies on submicrometre keratin hairs covering the soles of geckos. Each hair produces a miniscule force ~10-7 N (due to van der Waals and/or capillary interactions) but millions of hairs acting together create a formidable adhesion of ~10 N cm-2: sufficient to keep geckos firmly on their feet, even when upside down on a glass ceiling. It is very tempting to create a new type of adhesive by mimicking the gecko mechanism. Here we report on a prototype of such 'gecko tape' made by microfabrication of dense arrays of flexible plastic pillars, the geometry of which is optimized to ensure their collective adhesion. Our approach shows a way to manufacture self-cleaning, re-attachable dry adhesives, although problems related to their durability and mass production are yet to be resolved.
Adhesive Free Process for Writing Conductive
Painter, Kevin
Adhesive Free Process for Writing Conductive Tracks / Circuits on Dielectric / RF Substrates Problem this technology solves: Provides a method for directly writing metallic tracks onto ceramics below show the process applied to Aluminium foil on a glass substrate (left hand) and Copper foil on LCP
Collagories for Relational Adhesive Rewriting Wolfram Kahl
Smith, Spencer
morphisms", and show that they are sufficient for accommodating the relation-algebraic approach to graph approach to graph transformation. but thanks to their relation-algebraic flavour provide a more accessible form Adhesive Categories 11 6 Collagories of Semi-Unary Algebras and Bisimulations 14 7 Reducts Along
Si/Cu Interface Structure and Adhesion
NASA Astrophysics Data System (ADS)
Wang, Xiao-Gang; Smith, John
An ab initio investigation of the Si(111)/Cu(111) interfacial atomic structure and adhesion is reported [1]. Misfit dislocations appear naturally, as do hcp interfacial silicide phases that vary with temperature. The silicides form in the interface even at relatively low temperatures. These results are consistent with available experimental data. [1] Xiao-Gang Wang, John Smith, Physical Review Letters 95, 156102 (2005).
Flowmeter determines mix ratio for viscous adhesives
NASA Technical Reports Server (NTRS)
Lemons, C. R.
Flowmeter determines mix ratio for continuous flow mixing machine used to produce an adhesive from a high viscosity resin and aliphatic amine hardener pumped through separate lines to a rotary blender. The flowmeter uses strain gages in the two flow paths and monitors their outputs with appropriate instrumentation.