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Concentrations of follicle regulatory protein, steroids and gonadotrophins in antral fluids from women stimulated with metrodin and hCG.
Concentrations of immunoreactive follicle regulatory protein (FRP) were determined in 184 follicular fluid samples recovered from 30 patients in whom ovarian stimulation before oocyte recovery and in-vitro fertilization was induced with FSH (150 i.u./day). Ovum recovery was scheduled when the diameters of greater than or equal to 2 follicles reached 15-17 mm and serum oestradiol values were 740 pM/follicle. The mean level of FRP in fluid from follicles yielding oocytes which fertilized and cleaved within 48 h of recovery (24.4 +/- 3.08 immunoreactive units [IRU]/ml; 1 IRU = approximately 1 ng pig FRP) was higher than that in fluid from follicles yielding oocytes which did not fertilize (10.5 +/- 1.67 IRU/ml, P less than 0.05). FRP in fluid from follicles yielding oocytes which fertilized but did not cleave within 48 h of recovery was 17.2 +/- 2.89 IRU/ml. Overall, concentrations of FRP did not correlate with follicular fluid volume or with FSH or LH concentrations, but were positively related to prolactin, oestradiol and total protein levels (P less than 0.04). The results indicate that the FRP content of follicular fluid may be predictive of follicle/oocyte maturity. A dose-dependent increase in release of FRP by pig granulosa cells cultured in medium supplemented with 10-100 ng prolactin/ml was demonstrated. Prolactin may, therefore, be an important determinant of FRP production by granulosa cells. | {
"pile_set_name": "PubMed Abstracts"
} |
Vasoactive effects of ketamine on isolated rabbit pulmonary arteries.
Ketamine has been used in patients with congenital heart disease and pulmonary hypertension with hypothetical controversy. Its direct effect on pulmonary arteries has not yet been clearly characterized. This in vitro study was performed to determine the direct vasoactive effects of ketamine on isolated rabbit pulmonary arteries. Responses of pulmonary artery rings from New Zealand white rabbits were assessed in the presence and absence of intact endothelium and with or without precontraction by norepinephrine (NE, 3 x 10(-6)M) or potassium chloride (KCl, 3 x 10(-2)M). Using a preparatory tissue bath, cumulative concentration response curves of ketamine were obtained at different concentrations (0.03, 0.1, 0.3, 1, 3 mM) after a period of stabilization. Ketamine caused a dose-related vasodilation on KCl-precontracted pulmonary arteries. It elicited almost 100% relaxation at a concentration of 3 mM. Ketamine also induced a dose-related vasodilation on NE-precontracted pulmonary arteries at a lesser degree. All of the effects were endothelium independent. In conclusion, ketamine has strong endothelium-independent, direct vasodilatory effects on isolated rabbit pulmonary arteries. Ketamine may act through Ca++ channel-blocking effect as well as inhibition of Ca++ release from sarcoplasmic reticulum. | {
"pile_set_name": "PubMed Abstracts"
} |
Cardiovascular prevention in the Hartslag Limburg project: effects of a high-risk approach on behavioral risk factors in a general practice population.
This study describes a general-practice-based high-risk cardiovascular prevention approach in Maastricht, The Netherlands (1999-2003). The intervention consisted of a complete registration of risk factors, optimization of medical treatment and health counseling on high fat consumption, smoking and physical inactivity. Behavioral effects were assessed in a trial, randomization by practice and usual care as control. Validated questionnaires were completed by 1300 patients at baseline, 1174 after 4 months (90.3%) and 1046 (80.5%) after 18 months. After 4 months, intention-to-treat analyses revealed a decrease in saturated fat intake of 1.3 points (scale ranging from 7 to 30 points, p=0.000). This was partly sustained after 18 months (-0.5 points, p=0.014). After 18 months, obese intervention patients were more likely to be sufficiently physically active than their control counterparts (OR=1.90, p=0.023). No intervention effects were found for smoking. Given the multiple factor and multiple component high-risk approach, the intervention had modest effects on only some of the behavioral risk factors addressed. Process data showed that the registration of risk factors and the optimization of medical treatment were only partly implemented, that the health counseling component could be further improved and that the intervention could benefit from additional health promoting strategies. | {
"pile_set_name": "PubMed Abstracts"
} |
Retrieving mutation-specific information for human proteins in UniProt/Swiss-Prot Knowledgebase.
The UniProt/Swiss-Prot Knowledgebase records about 30,500 variants in 5,664 proteins (Release 52.2). Most of these variants are manually curated single amino acid polymorphisms (SAPs) with references to the literature. In order to keep the list of published documents related to SAPs up to date, an automatic information retrieval method is developed to recover texts mentioning SAPs. The method is based on the use of regular expressions (patterns) and rules for the detection and validation of mutations. When evaluated using a corpus of 9,820 PubMed references, the precision of the retrieval was determined to be 89.5% over all variants. It was also found that the use of nonstandard mutation nomenclature and sequence positional correction is necessary to retrieve a significant number of relevant articles. The method was applied to the 5,664 proteins with variants. This was performed by first submitting a PubMed query to retrieve articles using gene or protein names and a list of mutation-related keywords; the SAP detection procedure was then used to recover relevant documents. The method was found to be efficient in retrieving new references on known polymorphisms. New references on known SAPs will be rendered accessible to the public via the Swiss-Prot variant pages. | {
"pile_set_name": "PubMed Abstracts"
} |
[Digital radiography--results of a user survey (A) and consensus conference (B)].
Digital radiography is increasingly replacing conventional radiography in imaging. For some years now, the pros and cons of this new method have been subject to intense discussions. For further discussion, the present article describes the results of an inquiry among users and of a consensus conference held in March 1996 in Munich. Comments and interpretations have been omitted on purpose. | {
"pile_set_name": "PubMed Abstracts"
} |
SNPpath: characterizing cattle SNPs by enriched pathway terms.
High-density single nucleotide polymorphism (SNP) microarrays have made large-scale genome-wide association studies (GWAS) and genomic selection (GS) feasible. Valuable insight into the genetic basis underlying complex polygenic traits will likely be gained by considering functionally related sets of genes simultaneously. SNPpath, a suite of computer-generated imagery-based web servers has been developed to automatically annotate and characterize cattle SNPs by enriched KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway terms. The SNPpath allows users to navigate and analysis large SNP sets and is the only web server currently providing pathway annotations of cattle SNPs in National Center for Biotechnology Information's dbSNP database and three commercial platforms. Hence, we describe SNPpath and provide details of the query options, as well as biological examples of use. The SNPpath may be favorable for the analysis of combining SNP association analysis with pathway-driven gene set enrichment analysis and is freely available at http://klab.sjtu.edu.cn/SNPpath. | {
"pile_set_name": "PubMed Abstracts"
} |
Ozonation of chlorophenylurea pesticides in water: reaction monitoring and degradation pathways.
The degradation of mono- and dichlorophenylureas under ozone/hydrogen peroxide conditions was investigated in order to establish the effect of the structural parameters. The N-dimethyl phenylureas (mono- and dichloro) appear to differ strongly from the corresponding N-methyl N-methoxy analogues in terms of disappearance of the parent pesticide and evolution of the by-products identified by MS and MS-MS. The degradation rate of the latter is slower by a factor of 2.5 giving rise to additional pathways (hydroxylation of the phenyl ring and carbinolamine intermediate). Experiments with 14C-labelled compounds allow a complete determination of the mass balances obtained after solid-phase-extraction (SPE). This study demonstrates the interest of SPE for reaction monitoring and compares the performances of different types of phases for this purpose used alone or in combination. Mineralisation is also evaluated regarding 14CO2 production and found to contribute up to 20% in the degradation process. | {
"pile_set_name": "PubMed Abstracts"
} |
Full-fat rice bran and oat bran similarly reduce hypercholesterolemia in humans.
Scientific studies support recommendations to increase dietary soluble fiber as part of hyperlipidemia treatment. Rice bran contains minimal soluble fiber, but rice bran oil has a hypolipidemic effect. Full-fat rice bran was compared with oat bran and a rice starch placebo in hyperlipidemic humans to see if it might have a role in the treatment of hyperlipidemia. Moderately hypercholesterolemic (5.95-8.02 mmol/L), nonsmoking, nonobese adults were studied in a 6-wk, randomized, double-blind, noncross-over trial. Three groups added 84 g/d of a heat-stabilized, full-fat, medium-grain rice bran product (n = 14), oat bran product (n = 13) or rice starch placebo (n = 17) to their usual low-fat diet. Serum cholesterol, triglycerides, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), apoA1 and apoB were measured before and at the end of the supplementation period. Serum cholesterol decreased significantly (P </= 0.05) by 8.3 +/- 2.4% and 13.0 +/- 1.8% in the rice bran and oat bran groups, respectively, but there was no change in the rice starch group. This change was attributable to LDL-C, which decreased by 13.7 +/- 2.8% in the rice bran group and 17.1 +/- 2.4% in the oat bran group (P </= 0.05). Serum apoB decreased proportionately. There was no consistent effect on triglycerides within each group and HDL-C and apoA concentrations did not change. The LDL-C:HDL-C ratio decreased significantly in the rice bran and oat bran groups. Stabilized, full-fat rice bran or oat bran, added to the prudent diet of hyperlipidemic adults, similarly reduced cholesterol and LDL-C and improved lipid ratios in 78% of these individuals. Rice bran, as well as oat bran, should be included in the prudent diet of individuals with hyperlipidemia. | {
"pile_set_name": "PubMed Abstracts"
} |
Quantification of GABA(A) receptor subunit mRNAs by non-radioisotopic competitive RT-PCR utilizing plate-based EIA methodology.
We developed a non-radioisotopic quantitative competitive RT-PCR method for the measurement of gamma-aminobutyric acid (GABA) type A receptor subunit mRNA levels. The specificity of the method was optimized by the use of four subunit-specific oligonucleotides in the sequential steps: reverse transcription, polymerase chain reaction (PCR), and detection. The biotinylated PCR products were bound on streptavidin-coated microtiter plates allowing detection of the products using dinitrophenyl (DNP)-labeled probes and anti-DNP alkaline phosphatase conjugate. The method was set up for the six major cerebellar GABA(A) receptor subunits: alpha1; alpha6; beta2; beta3; gamma2 and delta. The method is quantitative and rapid. With a large dynamic range from 10 fg to 1 ng of subunit mRNA, the accuracy was 12 and 19% (intra- and interassay coefficients of variation, respectively), which might be improved by using a smaller range of standards. The use of a double logarithmic standard curve [log (standard to competitor signal) vs. log (standard mRNA originally present)] requires only one reaction from each sample, allowing the analysis of a large number of samples in one experiment. | {
"pile_set_name": "PubMed Abstracts"
} |
Commentary on "Proteasome Inhibitors: A Novel Class of Potent and Effective Antitumor Agents".
The relatively recent clinical success of bortezomib, particularly in multiple myeloma, has established the validity of the proteasome as a viable target for anticancer drug development. This highly cited 1999 Cancer Research article from Adams and colleagues was published during the period when this drug was transitioning from preclinical studies to phase I clinical trial status. Their results detail structure-activity analyses using a series of boronic acid proteasome inhibitors and correlate cytotoxicity with inhibition of proteasome activity. In and of itself, the recognition that interference with proteasome functions represented a novel therapeutic approach likely underlies the popularity of this article. In addition, the provision of in vitro (at that time using the NCI 60 cell line panel) and in vivo antitumor activity, toxicology, and mouse pharmacokinetic and pharmacodynamic data provided a solid basis for establishing the future credentials for bortezomib to gain initial FDA approval in 2003. Cancer Res; 76(17); 4916-7. ©2016 AACRSee related article by Adams et al., Cancer Res 1999;59:2615-22Visit the Cancer Research 75(th) Anniversary timeline. | {
"pile_set_name": "PubMed Abstracts"
} |
Device Applications of Side-Chain Ferroelectric Liquid Crystalline Polymer Films
Side-chain ferroelectric liquid crystalline polymers are currently used in a number of applications, including displays and electrical sensors. Comparisons with existing technologies and materials indicate that relative to ceramics, such polymers have lower figures of merit but offer greater durability in sensor applications. | {
"pile_set_name": "PubMed Abstracts"
} |
Radiation-induced lung injury.
Radiation therapy (RT) for thoracic-region tumors often causes lung injury. The incidence of lung toxicity depends on the method of assessment (eg, radiographs, patient's symptoms, or functional endpoints such as pulmonary function tests). Three-dimensional (3D) treatment planning tools provide dosimetric predictors for the risk of symptomatic RT-induced lung injury and allow for beams to be selected to minimize these risks. A variety of cytokines have been implicated as indicators/mediators of lung injury. Recent work suggests that injury-associated tissue hypoxia perpetuates further injury. Sophisticated planning/delivery methods, such as intensity modulation, plus radioprotectors such as amifostine, hold promise to reduce the incidence of RT-induced lung injury. | {
"pile_set_name": "PubMed Abstracts"
} |
Fabrication of large area nanoprism arrays and their application for surface enhanced Raman spectroscopy.
This work demonstrates the fabrication of metallic nanoprism (triangular nanostructure) arrays using a low-cost and high-throughput process. In the method, the triangular structure is defined by the shadow of a pyramid during angle evaporation of a metal etching mask. The pyramids were created by nanoimprint lithography in polymethylmethacrylate (PMMA) using a mould having an inverse-pyramid-shaped hole array formed by KOH wet etching of silicon. Silver and gold nanoprism arrays with a period of 200 nm and an edge length of 100 nm have been fabricated and used as effective substrates for surface enhanced Raman spectroscopy (SERS) detection of rhodamine 6G (R6G) molecules. Numerical calculations confirmed the great enhancement of electric field near the sharp nanoprism corners, as well as the detrimental effect of the chromium adhesion layer on localized surface plasmon resonance. The current method can also be used to fabricate non-equilateral nanoprism and three-dimensional (3D) nanopyramid arrays, and it can be readily extended to other metals. | {
"pile_set_name": "PubMed Abstracts"
} |
[3H]5'-N-ethylcarboxamide adenosine binds to both Ra and Ri adenosine receptors in rat striatum.
Adenosine analogs such as 5'-N- ethylcarboxamide adenosine and N6-cyclohexyladenosine stimulate or inhibit adenosine cyclase activity in preparations of rat striatum depending on the assay conditions. N6-cyclohexyladenosine inhibits but does not stimulate adenosine cyclase activity in preparations of hippocampus. These findings suggest that the striatum contains both Ra (stimulatory) and Ri (inhibitory) adenosine receptors while the hippocampus contains only Ri receptors. We have previously shown that [3H]N6-cyclohexyladenosine binds to Ri receptors in rat hippocampus ( Yeung and Green 1983). Comparisons of the characteristics of [3H]5'-N- ethylcarboxamide adenosine and [3H]N6-cyclohexyladenosine binding to hippocampus show that [3H]5'-N- ethylcarboxamide adenosine also binds to Ri receptors with high affinity. [3H]5'-N- ethylcarboxamide adenosine binds to Ri receptors in the striatum and to a second site that is present in striatum but not hippocampus. High affinity binding of both ligands to Ri receptors can be blocked by treatments with N-ethylmaleimide that do not markedly affect [3H]5'-N- ethylcarboxamide adenosine binding to the second site in the striatum. The pharmacological characteristics of the second site indicate that it is the Ra adenosine receptor. | {
"pile_set_name": "PubMed Abstracts"
} |
Suppression of radiofrequency interference in cardiac gated MRI: a simple design.
A simple design is proposed to suppress the noise pickup in the ECG leads from RF and gradient pulses during NMR imaging. The ECG signal is passed through a low-pass filter and a common-mode-rejection amplifier to reduce erroneous signal generated by the electrical ground loops. The output is gated through a CMOS switch to blank the preamplifier from the NMR during data acquisition. | {
"pile_set_name": "PubMed Abstracts"
} |
Role of cyclic AMP in the induction of histamine secretion from mast cells.
Immunological activation of rat peritoneal mast cells induced a transient elevation in the intracellular concentration of cyclic AMP. Enhancement or suppression of this rise by appropriate adenosine analogues produced parallel changes in histamine secretion. However, pharmacological activation of the cell with a number of diverse ligands induced histamine release without any accompanying changes in cyclic AMP. Moreover, this release was modulated by adenosine analogues in identical fashion to IGE-directed ligands but again without affecting cyclic AMP. On the basis of these results, the possible role of cyclic AMP in the induction of histamine secretion is critically considered. | {
"pile_set_name": "PubMed Abstracts"
} |
The metabolism and excretion of curcumin (1,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) in the rat.
Curcumin labelled with deuterium and tritium was prepared. Oral and intraperitoneal doses of [3H]curcumin led to the faecal excretion of most of the radioactivity. 2. Intravenous and intraperitoneal doses of [3H]curcumin were well excreted in the bile of cannulated rats. 3. The major biliary metabolites were glucuronides of tetrahydrocurcumin and hexahydrocurcumin. A minor biliary metabolite was dihydroferulic acid together with traces of ferulic acid. Metabolites were identified using chemical ionization mass spectrometry. | {
"pile_set_name": "PubMed Abstracts"
} |
The angiotensin type 2 receptor mediates RNA synthesis in A10 vascular smooth muscle cells.
This study was designed to define more precisely the relationship between specific angiotensin receptors and the growth of vascular smooth muscle cells in response to angiotensin II. These experiments employed quiescent A10 cells which were characterized as smooth muscle by the expression of specific contractlle proteins. Cell growth was monitored by measuring the incorporation of metabolic precursors into RNA or DNA. The treatment of A10 cells with angiotensin II (1 microM) stimulated a hypertrophic response as indicated by an increase in RNA synthesis and protooncogene expression in the absence of DNA synthesis. This increase in RNA synthesis could be blocked by PD123319, an AT2 antagonist, but not by losartan, an AT1 antagonist. RT-PCR analysis demonstrated that quiescent A10 cells express only the AT2 receptor while proliferating A10 cells express the AT1a and AT1b receptors in addition to the AT2 receptor. In addition, induction of AT2 receptor-mediated RNA synthesis was prevented by indomethacin, a cyclooxygenase inhibitor. These studies therefore support a direct connection between the AT2 receptor and smooth muscle growth that is mediated, in part, by prostaglandin synthesis. | {
"pile_set_name": "PubMed Abstracts"
} |
[Effectiveness of vitamin A acid in diseases of the mouth mucosa: lichen ruber planus, leukoplakias and geographic tongue].
52 patients, with different pattern of oral lichen planus, pre-malignant leukoplakia or geographic tongue, were treated with vitamin A acid. The systemic medication resulted in regression of discrete papules and leukoplakia-like appearance of oral lichen planus. Linear-hypertrophic pattern of the oral mucosa showed distinct involution only by topical administration of vitamin A acid. Also the patients suffering from pre-malignant leukoplakia or geographic tongue partly improved after a vitamin A acid therapy. Systemic side effects were noted after ignoring the tolerance limit (30 mg/day vitamin A acid/3 weeks). Inflammation and occasionally maceration appeared when local treatment was used over 3 weeks. Recurrence was observed in 11 patients. | {
"pile_set_name": "PubMed Abstracts"
} |
[The utilization of health services and the motives for consultation as indicators of family dysfunction].
To analyse the relationship between the reasons for seeking care on demand and use of the health services on the one hand and disturbances in the family dynamic, on the other, with an attempt to determine indicators of family dysfunction. Crossover descriptive study where the sample was obtained by systematic sampling. The family APGAR test was applied to the whole sample, along with an analysis of the use of services and the reasons for attendance. Almanjayar Health Centre during the first 6 months of 1992. 356 patients over 18. We confirmed that the likelihood of belonging to a dysfunctional family was 77%, with a risk of 6.5 for hyper and normal users. Regarding reasons for seeking care, those who attended because of ill-defined signs and symptoms are 6.21 times more likely to present a family dysfunction than the rest of those interviewed. Patients with ill-defined symptoms or psychiatric disorders who are hyper-users are 7.20 times more likely to present some family dysfunction. It will be useful to carry out a study of family function among hyper-users, those who attend because of ill-defined signs and symptoms and people with mental health problems. | {
"pile_set_name": "PubMed Abstracts"
} |
Preferential inhibition of the activity of a stimulatory protein of eukaryotic transcription by platinum (II) complexes.
The effect of platinum(II) complexes on RNA polymerase II was studied. (D-Glucuronato)(1R,2R-cyclohexanediamine)platinum(II) nitrate (II-GHP) preferentially inhibited RNA synthesis in the presence of S-II, an essential component of eukaryotic transcription. When DNA was pretreated with I-GHP, its template activity decreased significantly, especially when assayed in the presence of S-II. The target of platinum(II) complexes is probably DNA. When DNA is modified, regulatory proteins of transcription, such as S-II, seem to lose their function preferentially on such a template, resulting in the inhibition of RNA synthesis. | {
"pile_set_name": "PubMed Abstracts"
} |
Usefulness of contrast-enhanced US in the diagnosis of acute gangrenous cholecystitis: A comparative study with surgical and pathological findings.
To prospectively determine the usefulness of contrast-enhanced ultrasound (CEUS) in the diagnostic assessment of acute gangrenous cholecystitis, using histopathology as the reference method. The local institutional review board approved the study protocol, and all patients at enrollment provided a written informed consent. From December 2011 to July 2014, all patients with a clinical-sonographic diagnosis of acute cholecystitis underwent a CEUS examination. We included only patients who underwent cholecystectomies within 24-h of CEUS. Radiologists in the course of routine clinical care interpreted the US and CEUS images at the end of the examination, filling out a questionnaire. Two radiologists, blinded to the final diagnosis, independently reviewed the video CEUS sequences for the presence of defects of the gallbladder wall enhancement. Associations between the sonographic findings and histological gangrenous cholecystitis were evaluated by using univariate and multivariate logistic regression analysis. A total of 150 patients were analyzed. The histological diagnoses were 41 (27%) nongangrenous cholecystitis and 109 acute gangrenous cholecystitis (73%). Multivariate analysis of the predictive parameters at univariate analysis revealed that only leukocytosis, diabetes mellitus, lithiasis and defects of wall enhancement on CEUS were independent variables related to gangrenous cholecystitis. The presence of enhancement defects on CEUS enabled the diagnosis of the gangrenous form with sensitivity between 85 and 91% and specificity of 67.5-84.8%. Interobserver agreement for CEUS interpretation was good (median k value: 0.664; range, 0.655-0.680). Local or widespread absence of gallbladder wall enhancement on CEUS is associated with the presence of gangrenous acute cholecystitis. | {
"pile_set_name": "PubMed Abstracts"
} |
RECURRENT BRANCH RETINAL ARTERY OCCLUSION FROM SUSAC SYNDROME: CASE REPORT AND REVIEW OF LITERATURE.
We report a patient with branch retinal artery occlusion predominant Susac syndrome and review the literature on current diagnostic modalities and therapeutic approaches for this rare condition. Case report. A 23-year-old white male presented with a 5-month history of a scotoma in his right eye vision, headaches, and intermittent paresthesias of the lower extremities. Ophthalmic examination was normal with the exception of a hypopigmented small retinal area inferonasal to the fovea in the right eye. Optical coherence tomography demonstrated inner retinal atrophy and optical coherence tomography angiography showed deep capillary layer vessel dropout in both eyes. Ultra-wide-field fluorescein angiography revealed bilateral arteriolar wall hyperfluorescence. Corpus callosal lesions were present on magnetic resonance imaging. Lumbar puncture demonstrated elevated protein. Audiogram was normal. A diagnosis of Susac syndrome was made. The patient initially received oral steroids followed by intravenous steroids and mycophenolate mofetil because of new branch retinal artery occlusions. Thirteen months after initial presentation, the vision was stable at 20/20 in both eyes. It is a diagnostic challenge when recurrent branch retinal artery occlusion secondary to Susac syndrome presents without the classic symptoms. Optical coherence tomography angiography and subtle magnetic resonance imaging findings aided in early recognition of the diagnosis in our patient. Ultra-wide-field fluorescein angiography was an important tool in disease monitoring. Aggressive management with intravenous corticosteroids and initiation of immunosuppression resulted in long-term preservation of vision and improvement in visual field. | {
"pile_set_name": "PubMed Abstracts"
} |
Metabolic effects of graded glucagon infusions in man: inhibition of glucagon, insulin, and somatostatin response to arginine.
Insulin inhibits its own release (autofeedback), and growth hormone (GH) inhibits the GH response to a variety of stimuli. The aim of this study was to evaluate whether glucagon (G) can modify pancreatic G (IRG) release in humans. Seven healthy men received intravenous (i.v.) arginine (30 g in 30 minutes) 240 minutes after the beginning of a 0.9% NaCI saline infusion and a 2.5-, 4.0-, and 8.0-ng/kg.min-1 porcine G infusion, with each infusion lasting 360 minutes. All G infusions yielded stable and dose-related plasma IRG levels, and the 4.0- and 8.0-ng/kg.min-1 G infusions decreased plasma free fatty acids (FFA) and blood glycerol and beta-OH-butyrate levels and elicited insulin (IRI) release, and the 8.0-ng/kg.min-1 G infusion elicited GH release and increased blood glucose (BG) levels; somatostatin (SRIF) levels were not affected by G infusions. At 240 minutes, plasma IRG levels were higher during G infusion than during saline infusion, whereas serum IRI and BG levels had returned to preinfusion levels. At this point, G infusions decreased the integrated (240 to 300 minutes) IRG, IRI, BG, and SRIF responses, but not the GH response to arginine. These data indicate that prolonged G infusions decrease the IRG response to arginine; in addition, G decreases plasma FFA levels, and higher G doses stimulate IRI release and exert a self-limited hyperglycemic effect. The fact that the IRI response to arginine was decreased by G could be due to a refractoriness of beta cells to subsequent stimuli; the decreased SRIF response to arginine is likely due to G itself or to a decrease of plasma FFA levels. | {
"pile_set_name": "PubMed Abstracts"
} |
Effects of starvation and body mass on drought tolerance in the soil collembolan Folsomia candida.
The effects of starvation and body mass on drought tolerance in Folsomia candida were investigated. Starvation for up to 6 weeks did not reduce tolerance to drought (98.2% RH) compared to a nonstarved control group. Animals starved for 1, 2 or 6 weeks prior to drought exposure showed no systematic differences in the accumulation of sugars and polyols (SP). In all groups exposed to drought SP constituted 9-13% of dry weight and was distributed in myoinositol, glucose and a third unidentified compound. At 97.3% RH large individuals (9 weeks old) survived better than small individuals (2 or 3 weeks old). However, no correlation was found between body mass and drought tolerance at relative humidities above 97.3% RH. The results suggest that starvation for ecologically relevant periods of time does not impair the ability to produce desiccation-protective SP in F. candida, and that both small and large life stages are well adapted to dry soil conditions. | {
"pile_set_name": "PubMed Abstracts"
} |
Serial bone scintigraphy for assessing the effectiveness of treatment of osseous metastases from prostatic cancer.
130 serial bone scintigrams were performed to evaluate the course of skeletal metastases under treatment in 36 patients with prostatic cancer. During a successful treatment scintigraphic controls revealed a significant decrease of the metastatic 99mTc-diphosphonate uptake in 14 patients and sometimes even a complete normalization of the skeletal radioactivity distribution, whereas a progression characterized by an increased multifocal radioactivity concentration was registered in 16 patients indicating the failure of the initiated therapy. Based on these results of follow-up studies scintigraphic bone imaging can be recommended for the assessment of the effectiveness of on-going therapy of skeletal metastases. | {
"pile_set_name": "PubMed Abstracts"
} |
Preservation of implicit memory in adult children of alcoholics.
The authors investigated implicit memory in 21 adult children of alcoholics (ACAs) and 24 control individuals (all college undergraduates) who performed a serial reaction time task (SRT) to evaluate their implicit memory performance and their formation of new associations. Each group was presented with 5 blocks of 100 trials per block in which Blocks 1-4 contained a 10-item repeating sequence; Block 5 was a pseudo-random sequence. The latency difference between Block 4 and Block 5 presumably measure implicit memory. The amount of implicit memory did not differ (in ms) between the ACAs (M = 55 ms) and the controls (M = 67 ms). Implicit memory (at least as measured by the SRT task) appears to be preserved in ACAs. | {
"pile_set_name": "PubMed Abstracts"
} |
Interaction between centrally acting hypotensive drugs and tricyclic antidepressants.
From clinical experience it is known that the hypotensive action of clonidine and alpha-methyl-DOPA is antagonized by desipramine. This antagonism was investigated in detail in chloralose-anaesthetized cats. Both the centrally acting hypotensive agents and the tricyclic antidepressants where infused into the left vertebral artery. (1) The central hypotensive action clonidine was antagonized by desipramine, imipramine, amitriptyline, protriptyline and mianserine. For the inhibition of the hypotensive action of clonidine by protriptyline a parallel shift of the dose-response curve was obtained, indicating the possibility of a competitive antagonism. The central hypotensive action of alpha-methyl-DOPA was antagonized by desipramine and imipramine and that of amphetamine by imipramine. (2) The modest central hypotensive action of tricyclic antidepressants themselves and that of cocaine is explained by means of the inhibition of noradrenaline re-uptake in the CNS, brought about by these compounds. (3) It seems likely that the antagonism occurs at the level of central alpha-adrenoreceptors in the brain stem. (4) The antagonism probably reflects a general interaction between centrally acting hypotensive drugs and tricylclic antidepressants. The alpha-sympatholytic properties of the tricyclic antidepressants probably give rise to a blockade of the central alpha-adrenoreceptors, stimulated by clonidine, noradrenaline (via amphetamine) and alpha-methylnoradrenaline (from alpha-methyl-DOPA). The cocaine-like activity of antidepressants does not play a part. | {
"pile_set_name": "PubMed Abstracts"
} |
Chronic lateral ankle instability and associated conditions: a rationale for treatment.
Ankle sprains have a high incidence of associated injuries and conditions that may be unrecognized at the initial time of injury. Failure to treat these conditions at the index surgery may compromise outcomes and delay recovery. The purpose of this study was to determine the type and frequency of associated injuries and conditions in military patients with chronic lateral ankle instability. Between 1996 and 2002, 160 patients had 180 modified Broström-Gould lateral ankle ligament reconstructions for chronic ankle instability. A retrospective review of the clinical history, physical examination, radiographs, and intraoperative findings was conducted. The overall incidence of associated extra-articular conditions and injuries found in this study was 64%; 115 conditions were identified in 180 ankles. Peroneal tendon injuries occurred with the highest frequency (28%), followed by os trigonum lesions (13%), lateral gutter ossicles (10%), hindfoot varus alignment (8%), anterior tibial spurs (3%), and tarsal coalitions (2%). Twenty revision lateral ankle ligament reconstructions were required for either persistent pain or recurrent instability. The most common associated conditions were undiagnosed hindfoot varus alignment abnormalities (28%) followed by untreated peroneal injuries (25%). This study confirms the frequency of conditions associated with lateral ankle instability and emphasizes several conditions that have received little attention in the literature. Identifying these associated conditions before surgery enables the surgeon to treat all conditions at one operation, returning the patient to full activity sooner. Guidelines are presented to assist clinicians in screening patients for these associated conditions. | {
"pile_set_name": "PubMed Abstracts"
} |
Rehabilitation robotics: an academic engineer perspective.
In this paper, we present a retrospective review of our efforts to revolutionize the way physical medicine is practiced by developing and deploying rehabilitation robots. We present a sample of our clinical results with well over 600 stroke patients, both inpatients and outpatients. We discuss the different robots developed at our laboratory over the past 20 years and their unique characteristics. All are configured both to deliver reproducible interactive therapy and also to measure outcomes with minimal encumbrance, thus providing critical measurement tools to help unravel the key remaining question: what constitutes "best practice"? While success to date indicates that this therapeutic application of robots has opened an emerging new frontier in physical medicine and rehabilitation, the barrier to further progress lies not in developing new hardware but rather in finding the most effective way to enhance neuro-recovery. We close this manuscript discussing some of the tools required for advancing the effort beyond the present state to what we believe will be the central feature of research during the next 10 years. | {
"pile_set_name": "PubMed Abstracts"
} |
Effect of the YCD3-1 anti-mouse monoclonal on murine GvHD.
The potential for applying the YCD3-1 rat-anti-mouse IgG2b anti-CD3-epsilon monoclonal antibody (MAB) to the study of graft-versus-host disease (GvHD) in mouse models has been examined. This MAB, unlike the previously developed hamster-anti-mouse-CD3 MABs, had been reported to exhibit strong cytolytic properties when applied in vitro in the presence of complement. Therefore, it was of interest to determine whether it could be effectively used for T-cell depletion in mice to suppress GvHD in the same manner as the anti-human-CD3 MABs have been applied in clinical transplantation. Evaluation of the effectiveness of this antibody was carried out both under fully allogeneic MHC-mismatched and under unrelated-donor MHC-matched marrow transplant conditions. For both types of transplantation, depletion of the donor cells with YCD3-1 plus complement prior to their injection into lethally irradiated recipients significantly suppressed GvHD, resulting in survivals of 75-79%, as compared to 8-13% in the controls that received undepleted cells from the same donors (p < 0.0001). These results suggest that the YCD3-1 MAB may have a potential for use as a negative selection agent in the further definition of the roles of the various T-cell subtypes, as well as the possible roles of natural-killer cells, in future studies into the mechanisms of GvHD, and of the graft-versus-leukemia effect. | {
"pile_set_name": "PubMed Abstracts"
} |
Influence of temperature and relative humidity on the moulting success of Amblyomma limbatum and Aponomma hydrosauri (Acari: Ixodidae) larvae and nymphs.
This study compared the duration of the moulting periods of engorged larvae and nymphs of the ixodid ticks, Amblyomma limbatum and Aponomma hydrosauri, at different temperature/relative humidity regimes, and examined the relationships between the engorged weight of ticks and their weights after moulting. The results showed that for each species, there was a significant relationship between the weights of unfed nymphs and engorged larvae, and the weights of unfed adults and engorged nymphs. The weight of engorged nymphs was also a good indicator of their sex, with female ticks having heavier weights as engorged nymphs. Temperature and relative humidity had a marked effect on the moulting success of engorged ticks of both species. Aponomma hydrosauri larvae and nymphs were able to moult at lower temperatures than Amb. limbatum but most ticks, except Ap. hydrosauri larvae, failed to moult at 13 degrees C. Additionally, there was a marked decrease in the pre-moult times of ticks at higher temperatures, with larvae taking less time to moult than nymphs. At temperatures greater than 21 degrees C, Amb. limbatum took less time to moult than Ap. hydrosauri but this interspecific difference was less marked for nymphs. The interspecific differences in the responses of engorged larvae and nymphs to different temperatures and relative humidities correlated with interspecific differences in off-host behaviour and with the different climates the two species experience throughout most of their distributional range. | {
"pile_set_name": "PubMed Abstracts"
} |
Environmental benign synthesis, characterization and mechanism studies of green calcium hydroxide nano-plates derived from waste oyster shells.
Continuous dumping of oyster shells in open fields has been a global issue, causing serious problems in the water and human health. The conversion of those wastes into value-added products is highly desirable. Here, Green Calcium Hydroxide Nano-plates (GCHNPs) were first synthesized from waste oyster shells by a chemical precipitation method in an aqueous medium at 90 °C without using any additives. The crystal structure with a hexagonal portlandite (Ca(OH)2) was observed by both X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The crystal size of around 350-450 nm and specific surface area with 4.96 m2g-1 were confirmed by field emission scanning electron microscopy (FE-SEM) and Brunauer-Emmett-Teller (BET), respectively. In addition, a schematically organized new qualitative model for a mechanism was proposed to explain the genesis and evolution of GCHNPs from raw oyster shells. | {
"pile_set_name": "PubMed Abstracts"
} |
Extensor digitorum brevis manus muscle in association with a metacarpal boss.
Awareness of the existence of accessory muscles in the hand, such as the extensor digitorum brevis manus (EDBM) muscle, is important when making a differential diagnosis and considering the treatment of mass lesions with similar appearances. Cases of EDBM with associated dorsal wrist ganglion have been reported in earlier published reports. This report describes an unusual case of the EDBM muscle in association with carpometacarpal (CMC) boss. To the best of the authors' knowledge this has not been previously reported. | {
"pile_set_name": "PubMed Abstracts"
} |
Unilateral percutaneous pedicle screw instrumentation with minimally invasive TLIF for the treatment of recurrent lumbar disk disease: 2 years follow-up.
To compare the clinical and radiological outcomes of recurrent disk disease in patients who underwent unilateral and bilateral percutaneous pedicle screw instrumentation with Mis-TLIF. 10 patients treated with unilateral percutaneous instrumentation plus Mis-TLIF formed Group 1 while the other 10 patients treated with bilateral percutaneous instrumentation plus Mis-TLIF formed Group 2. Clinical outcomes were graded using the visual analog scale (VAS) and the Oswestry disability index (ODI) scores. Peroperative and 2-year follow-up scores were obtained. Postoperative imaging techniques were used for the assessment of fusion, subsidence and spinal alignment. According to preoperative and postoperative VAS/ODI scores, statistically significant differences were noted in the unilaterally and bilaterally instrumented group. However, a statistically significant difference was not observed between the unilateral and bilateral groups. Radiological evidence of successful arthrodesis was noted in 8 of 10 patients (80%) in the unilaterally instrumented group and in 9 of 10 patients (90%) in the bilaterally instrumented group at the 2 years follow-up. No metal failure, cage migration, vertebral fracture, subsidence or adjacent level disease was experienced. Mis-TLIF with unilateral percutaneous pedicle screw instrumentation is an excellent option in the treatment of selected recurrent disk disease patients. | {
"pile_set_name": "PubMed Abstracts"
} |
Validation of a helmet-based system to measure head impact biomechanics in ice hockey.
This study aimed to quantify differences between head acceleration measured by a helmet-based accelerometer system for ice hockey and an anthropometric test device (ATD) to validate the system's use in measuring on-ice head impacts. A Hybrid III 50th percentile male ATD head and neck was fit with a helmet instrumented with the Head Impact Telemetry (HIT) System for hockey and impacted at various speeds and directions with different interfaces between the head and helmet. Error between the helmet-based and reference peak accelerations was quantified, and the influence of impact direction and helmet-head interface was evaluated. Regression equations were used to reduce error. System-reported impact direction was validated. Nineteen percent of impacts were removed from the data set by the HIT System processing algorithm and were not eligible for analysis. Errors in peak acceleration between the system and ATD varied from 18% to 31% and from 35% to 64% for linear and rotational acceleration, respectively, but were reduced via regression equations. The relationship between HIT System and reference acceleration varied by direction (P < 0.001) and head-helmet interface (P = 0.005). Errors in impact azimuth were approximately 4%, 10%, and 31% for side, back, and oblique back impacts, respectively. This is the first comprehensive evaluation of peak head acceleration measured by the HIT System for hockey. The HIT System processing algorithm removed 19% of the impacts from the data set, the correlation between HIT System and reference peak resultant acceleration was strong and varied by head surface and impact direction, and the system error was larger than reported for the 6-degree-of-freedom HIT System for football but could be reduced via calibration factors. These findings must be considered when interpreting on-ice data. | {
"pile_set_name": "PubMed Abstracts"
} |
Na(+)-coupled transport of L-carnitine via high-affinity carnitine transporter OCTN2 and its subcellular localization in kidney.
The mechanism of Na(+)-dependent transport of L-carnitine via the carnitine/organic cation transporter OCTN2 and the subcellular localization of OCTN2 in kidney were studied. Using plasma membrane vesicles prepared from HEK293 cells that were stably transfected with human OCTN2, transport of L-carnitine via human OCTN2 was characterized. Uptake of L-[(3)H]carnitine by the OCTN2-expressing membrane vesicles was significantly increased in the presence of an inwardly directed Na(+) gradient, with an overshoot, while such transient uphill transport was not observed in membrane vesicles from cells that were mock transfected with expression vector pcDNA3 alone. The uptake of L-[(3)H]carnitine was specifically dependent on Na(+) and the osmolarity effect showed that Na(+) significantly influenced the transport rather than the binding. Changes of inorganic anions in the extravesicular medium and of membrane potential by valinomycin altered the initial uptake activity of L-carnitine by OCTN2. In addition, the fluxes of L-carnitine and Na(+) were coupled with 1:1 stoichiometry. Accordingly, it was clarified that Na(+) is coupled with flux of L-carnitine and the flux is an electrogenic process. Furthermore, OCTN2 was localized on the apical membrane of renal tubular epithelial cells. These results clarified that OCTN2 is important for the concentrative reabsorption of L-carnitine after glomerular filtration in the kidney. | {
"pile_set_name": "PubMed Abstracts"
} |
Nurses' participation in the end-of-life process in two paediatric intensive care units in Brazil.
The aim of this study was to evaluate the medical and nursing care provided to children in the last 24 hours of life in two Brazilian paediatric intensive care units and analyse the nurses' participation in the decision-making process for life support limitation (LSL). The study was based on an analysis of the patients' medical charts, looking at the medical and nursing care provided in the last 24 hours of life during a 6-month period in the two units, and on semi-structured interviews with 20 nurses to evaluate their participation in LSL decisions. The children were classified into two groups: those who were to receive full cardiopulmonary resuscitation (CPR) and a non-CPR group. A total of 34 deaths occurred during the study period. Of these, 17 (50%) were children that had been in the non-CPR group; there were only 10 recorded LSL plans in their medical charts. In the interviews, only 30% of the nurses mentioned active participation in LSL decisions. In conclusion, the paediatric intensive care nurses in these two Brazilian units did not participate much in LSL decisions, and the care offered in the last hours of life to children with terminal and irreversible illness was not primarily directed toward comfort and alleviating suffering. | {
"pile_set_name": "PubMed Abstracts"
} |
An experimental comparison of min-cut/max-flow algorithms for energy minimization in vision.
After [15], [31], [19], [8], [25], [5], minimum cut/maximum flow algorithms on graphs emerged as an increasingly useful tool for exact or approximate energy minimization in low-level vision. The combinatorial optimization literature provides many min-cut/max-flow algorithms with different polynomial time complexity. Their practical efficiency, however, has to date been studied mainly outside the scope of computer vision. The goal of this paper is to provide an experimental comparison of the efficiency of min-cut/max flow algorithms for applications in vision. We compare the running times of several standard algorithms, as well as a new algorithm that we have recently developed. The algorithms we study include both Goldberg-Tarjan style "push-relabel" methods and algorithms based on Ford-Fulkerson style "augmenting paths." We benchmark these algorithms on a number of typical graphs in the contexts of image restoration, stereo, and segmentation. In many cases, our new algorithm works several times faster than any of the other methods, making near real-time performance possible. An implementation of our max-flow/min-cut algorithm is available upon request for research purposes. | {
"pile_set_name": "PubMed Abstracts"
} |
Impact of delivery mode on the levels of essential trace elements in breast milk.
This study investigated whether the parturition mode (vaginal or cesarean [C-] section) affects breast milk concentrations of four essential trace elements (iron, copper, zinc, and manganese). Women giving birth at seven hospitals in seven different regions of China were enrolled in the study. Each participant provided breast milk, collected on postpartum day 3-5, for determination of iron, copper, zinc, and manganese concentrations. Breast milk concentrations of the subject trace elements were compared between women giving birth vaginally or via C-section. Of the 1243 women enrolled in the study, 617 (49.6%) gave birth via the vaginal route and 626 (50.4%) delivered via C-section. The mean milk concentrations of iron, copper, zinc, and manganese in the milk of women delivering via the vaginal route were higher than those in the milk of women delivering via C-section; only the copper concentration differences were statistically significant, after adjusting for confounding factors (p = .023). Delivery mode impacts breast milk concentrations of essential trace elements, with vaginal delivery being associated with higher essential trace element concentrations than C-sections. | {
"pile_set_name": "PubMed Abstracts"
} |
Achilles tendinitis in systemic lupus erythematosus: search for an associated inflammatory disease.
Except for traumatic and iatrogenic causes, Achilles tendinitis (AT) is mostly encountered in the context of inflammatory rheumatic diseases. This study aimed to describe AT in systemic lupus erythematosus (SLE). Among 158 SLE patients who fulfilled the SLE criteria of the ACR classification followed between 1980 and 2013, we selected those who experienced at least one episode of AT not caused by traumatic or toxicity factors. Eight patients (one male, seven females), median age 52 years (range: 35-68), presented with 11 episodes of AT within an average of 10.5 (0-21) years after SLE diagnosis. Clinical presentation of SLE was mainly cutaneous (eight of eight), and articular (seven of eight). Axial symptoms were reported in six patients, two of whom had HLA-B27-positive status, and fulfilled the Amor and European Spondylarthropathy Study Group criteria. Resolution of AT was good with nonsteroidal anti-inflammatory topical or systemic drug therapies, which kept SLE quiescent and avoided any increase of specific treatment. Although the association is rare, when AT occurs in SLE patients, physicians should look for associated spondylarthritis. | {
"pile_set_name": "PubMed Abstracts"
} |
Membrane dynamics of a myelin-like giant multilamellar vesicle applicable to a self-reproducing system.
A real time observation of a myelin-like giant multilamellar vesicle (mGMV) revealed that it divided into relatively small mGMVs when an aqueous solution of an electrolyte was added. Furthermore, the mGMV showed a division process accompanied by the growth of the dividing mGMVs when a bolaamphiphile which was composed of an electrolyte unit and a vesicular amphiphile unit was added. This vesicular system can be regarded as a self-reproduction of mGMV, where the added amphiphile acts as a supplier of both the vesicular amphiphile and the division initiator. | {
"pile_set_name": "PubMed Abstracts"
} |
Brain anomalies in encephalocraniocutaneous lipomatosis.
Encephalocraniocutaneous lipomatosis (ECCL) is a sporadically occurring neurocutaneous disorder characterized by ocular anomalies, skin lesions, and CNS anomalies. We report on four new patients with this syndrome. Additionally, we reviewed (i) the brain imaging studies and clinical data of these new cases of ECCL and six other previously published ECCL patients, and (ii) the literature on 42 other patients who had undergone some form of neuroimaging, including three cases with probable or uncertain ECCL diagnoses. Thirty-three of 52 patients showed intracranial lipomas, frequently of cerebello-pontine location, and/or spinal lipomatosis. The latter has been found in 12/13 patients who had imaging studies of the spine. Other frequent findings included congenital anomalies of the meninges, in particular arachnoid cysts, and remarkably asymmetric anomalies caused by putative focal vascular defects, such as (partial) atrophy of one hemisphere or thin cerebral mantle, porencephalic cysts and calcifications. Vessel anomalies were found in nine patients. No correlation between the brain anomalies and the degree of retardation or epilepsy could be established. These data provide evidence that the brain anomalies in ECCL are not primary brain malformations but arise secondary to a mesenchymal defect affecting mostly neural crest derivatives. | {
"pile_set_name": "PubMed Abstracts"
} |
[Effect of laparoscopic radical operation on systemic immunity in patients with colorectal cancer].
To compare the effect of laparoscopic radical operation and open operation on systemic immunity in patients with colorectal cancer. Sixty patients with colorectal cancer were randomly divided into laparoscopic and open operation groups from March 2004 to December 2004, each group had 30 cases. CRP, IgA, IgM, IgG, CD3 (+) cells, CD4 (+) cells, CD8 (+) cells, NK cells, CD4 (+) CD5RA (+) cells, CD4 (+) CD45RO (+) cells and lymphocytes in peripheral blood were counted and compared on the 1st day before operation, 3rd and 7th day after operation. The two groups were comparable as for age, tumor location and stages. In open operation group, lymphocyte counts were (1.09+/- 0.29) x 10(9)/L, CD4 (+) cell (0.54 +/- 0.14) x 10(9)/L, CD8 (+) cell (0.31 +/- 0.08) x 10(9)/L, CD4 (+) CD45RO (+) (61.1+/- 8.9)%, and IgM level (136.9+/- 52.8) IU/ml, IgG (115.2 +/- 45.7) IU/ml on the 3rd day after operation, CD8 (+) cell counts were (0.32 +/- 0.09) x 10 (9)/L, CD4 (+) CD45RO (+) cell (63.2 +/- 9.1)% on the 7th day after operation, were all significantly lower than those on the 1st day before operation respectively(P< 0.05, P< 0.01). In laparoscopic operation group, the decreases of such parameters except CD4 (+) CD45RO (+) cell (62.7 +/- 12.5)% were not obvious on the 3rd day after operation. There were significant difference in lymphocyte counts (1.29 +/- 0.37) x 10( 9 )/L, IgM (164.5 +/- 48.2) IU/ml and CD8 (+) cell counts (0.38 +/- 0.09) x 10 (9) /L on the 3rd day after operation between two groups (P< 0.05). Compared with open radical operation, laparoscopic radical operation has predominance in protecting systemic immunity to treat colorectal carcinoma. | {
"pile_set_name": "PubMed Abstracts"
} |
Single dose eradication of extensively drug resistant Acinetobacter spp. In a mouse model of burn infection by melittin antimicrobial peptide.
Bacterial infections caused by antibiotic resistant bacteria are the leading cause of morbidity and mortality after burn injuries. This issue has driven the need for promising antimicrobial drugs to eradication of bacterial pathogens. Accordingly, we aimed to determine the therapeutic value of melittin, as a natural Antimicrobial peptide (AMP), in eradication of extensively drug-resistant (XDR) Acinetobacter spp. on a mouse model of third degree burn infection. Melittin killed all examined XDR isolates at 4 μg/mL up to 3 h. Melittin caused significant fluorescence release from XDR isolates at the minimum dose of 0.062 μg/mL. Vesicle formation on the membrane and squeezing of bacteria followed by cell lysis indicated the membranolytic effect of melittin. Melittin at 32 μg/mL completely eradicated the colonized XDR bacteria on infected burn mice during 2 h. No toxicity was observed on injured or healthy derma, as well as circulating Red Blood Cells (RBCs) in the examined mice. Potent promising antibacterial activity of melittin and the lack of toxicity at the therapeutic dose can clarify that melittin can be implemented as a topical drug lead in a preclinical trial of third degree burn infections. | {
"pile_set_name": "PubMed Abstracts"
} |
Effect of IL-4 deletion on cardiac allograft survival in the BALB/c to 129Sv x C57BL/6 strain combination.
To investigate the effect of IL-4 deletion on cardiac allograft survival, vascularized BALB/c cardiac allografts were placed in C57BL/6, 129Sv x C57BL/6 (IL-4 +/+) or 129Sv x C57BL/6 IL-4 knockout mice (IL-4-/-). Untreated recipients rejected allografts in < 15 days while isografts survived indefinitely (> 100 days). Treatment with anti-CD4 (GK1.5) for 4 days at the time of allografting increased mean survival to > 100 days in C57BL/6, 90+/-16 days in 129Sv x C57BL/6 (IL-4 +/+) and 68 +/- 36 days in 129Sv x C57BL/6 (IL-4-/-) recipients. Although there was a trend towards shorter survival times in the IL-4-/- mAb-treated mice, survival in the three recipient groups was not significantly different (P = 0.07). A 30-day course of anti-CD4 did not further prolong BALB/c heart survival. All long-surviving hearts had histological evidence of parenchymal damage and transplant vascular disease. None of these recipients developed antigen-specific tolerance, since both donor and third party skin graft challenges were rejected when challenged at > 60 days post-graft and all primary grafts failed by 120 days. Thus the effects of IL-4 deletion were subtle and were seen only with low doses of immunosuppression in this high responder strain combination. | {
"pile_set_name": "PubMed Abstracts"
} |
Unravelling the key role of surface features behind facet-dependent photocatalysis of anatase TiO2.
The high activity of nanocrystallites is commonly attributed to the terminal high-energy facets. However, we demonstrate that the high activity of the anatase TiO2(001) facet in photocatalytic H2 evolution is not due to its high intrinsic surface energy, but local electronic effects created by surface features on the facet. | {
"pile_set_name": "PubMed Abstracts"
} |
Computed tomography of choledochocele.
One case of choledochocele is reported, and the findings on CT, endoscopic retrograde cholangiopancreatography, and surgery are described. At surgery, in addition to choledochocele, a large choledochal cyst in the proximal common bile duct was discovered. Choledochocele can be diagnosed by CT and can be recognized by the finding of a cystic mass contiguous with the distal common bile duct that invaginates into the contrast-filled duodenum. | {
"pile_set_name": "PubMed Abstracts"
} |
[The concept of the clinical use of serotonin adipinate in treating surgical patients].
The influence of serotonin adipinate on the mechanisms of development of tissue hypoxia, disturbances of the microcirculatory bed and smooth muscles before, during and after operative interventions was studied in experiments and clinical practice. The syndrome of serotonin insufficiency is described including smooth muscle insufficiency which can be abolished by serotonin adipinate administered at the early postoperative period irrespective of the cause of surgery, age and sex of the patient. Good results were obtained in treatment of patients after operations on the liver, pancrease, heart, in patients with the diabetic foot and in other diseases. No complications or lethal outcomes resulting from using serotonin adipinate were noted. | {
"pile_set_name": "PubMed Abstracts"
} |
Neutrophil superoxide anion generation during atorvastatin and fluvastatin therapy used in coronary heart disease primary prevention.
Neutrophil superoxide anion generation was measured during atorvastatin and fluvastatin therapy in patients with coronary heart disease (CHD) risk. The patients were randomly allotted into three groups. The atorvastatin group comprised 17 patients who were administered the drug orally 10 mg a day at bed time. The fluvastatin group consisted of 18 patients on an oral dose of 40 mg once daily at bed time. The control group comprised 12 healthy subjects with no drug administration. Blood samples were collected from cubital vein before and after 6-week therapy with these drugs and once in the control group. Neutrophil superoxide anion generation in whole blood without and with opsonized zymosan (OZ) stimulation was determined using superoxide dismutase from bovine erythrocytes. In the atorvastatin group, statistically significant (P < 0.05) decrease in superoxide anion generation by nonstimulated and OZ-stimulated neutrophils was observed after 6 weeks of therapy. In fluvastatin group, no changes in neutrophil superoxide anion generation were observed after the 6-week treatment period. Our study has shown an additional nonlipid mechanism of atorvastatin used in CHD primary prevention. | {
"pile_set_name": "PubMed Abstracts"
} |
Atraumatic perspectives of ART: psychological and physiological aspects of treatment with and without rotary instruments.
Atraumatic Restorative Treatment, ART, is a method of minimal caries intervention that uses only hand instruments. The aim of the present study was to explore a possible difference between the extent of discomfort experienced during dental treatment according to the ART approach and a method using rotary instruments. The study was performed in Indonesia. A total of 403 children were randomly divided in two groups. In each child, one class II restoration in a deciduous molar was made. One group received treatment using rotary instruments (750 r.p.m.). The other group was treated according to the ART approach. Glass ionomer cement was used for restoration in both groups. Discomfort scores were determined using both physiological measurements (heart rate) and behavioral observations (Venham) on specific moments during the treatment. Venham scores showed a marked difference between the two groups at most time points. Heart rate measurements were different at deep excavation. Also, a clear relation between Venham scores and heart rate measurements could be found at all time points. Confounding could be shown for operating dentist, gender of the patient and initial anxiety, not for age. No effect modification could be shown. It can be concluded that children treated according to the ART approach using hand instruments alone experience less discomfort than those treated using rotary instruments. | {
"pile_set_name": "PubMed Abstracts"
} |
[Assessment of the chronic toxic action of the herbicide, balagrin, in continuous and intermittent exposure regimens].
Chronic oral toxicity of the herbicide balagrin, a selective and perspective preparation for rural economy, was experimentally studied on 258 Wistar albino rats. Two treatment schedules using the combined trade product (20 percent balan and 80 percent xylol) were assayed: montonous - 1/20 LD50 balagrin (55 mg/kg) and 1/20 LD50 xylol (235 mg/kg), administered every day and every week for 4 months; intermittent - 4 months' every day application on alternate weeks of 1/10 LD50 balagrin (110 mg/kg) and 1/10 LD50 xylol (470 mg/kg) and 8 weeks' application by the same schedule of 1/20 LD50 balagrin and 1/20 LD50 xylol. The results of clinico-laboratory, biochemical and functional investigations showed that the toxic effect was more pronounced with monotonous administrations of the compound. The enzyme activities of HE, OCT and cellular LAP were increased, serum alpha-globulins were reduced, liver tissue ICDH and GIDH was increased, hepatic weight coefficient was reduced and testicular and brain CO activity was decreased. Proceeding from the experimental data, the compound is recommended for periodic application in agricultural practice. | {
"pile_set_name": "PubMed Abstracts"
} |
The effect of an optimised helmet fit on neck load and neck pain during military helicopter flights.
The main purpose of this study was to improve the helmet fit of military helicopter aircrew members and evaluate its effect on the experienced helmet stability (helmet gliding), neck load, neck pain, hot spots (pressure points), irritation/distraction, and overall helmet comfort during night flights. A within-subject design was used over a three-month period that consisted of two consecutive interventions of optimising the fit of the aircrew's helmets: 1) a new helmet fit using a renewed protocol and 2) replacement of a thermoplastic inner liner with a viscoelastic foam inner liner. A total of 18 pilots and loadmasters rated the outcome measures using the Visual Analogue Scales immediately after their night flights, for three night flights in total per measurement period. The optimised helmet fit resulted in a significant decrease in the experienced helmet gliding, neck load and pressure points, a decrease trend in the experienced neck pain and irritation/distraction, and a significant increase in the experienced overall helmet comfort during flight. These results demonstrate the importance of achieving an optimised helmet fit for military helicopter aircrew and that an optimised helmet fit might have implications for both health and safety concerns. | {
"pile_set_name": "PubMed Abstracts"
} |
Basal and exercise-induced neuroendocrine activation in patients with heart failure and in normal subjects.
Neuroendocrine activation is a pathophysiological response and an important prognostic marker in patients with chronic heart failure (CHF). Although chronic activation is well described, data on the responsiveness of the hormone systems are more limited. Most previous studies have looked at activation during maximal exercise, whereas we believe that activation at a submaximal level might be more pathophysiologically relevant. To compare exercise-induced neurohormonal activation between CHF patients and normal subjects using the same relative and submaximal workload. Twenty-three newly-diagnosed CHF patients and 18 age- and gender-matched healthy subjects were exercised at two workloads, which were calculated to correspond to 50 and 75% of each individual's heart rate response. In CHF patients, baseline levels of ANP, BNP, AVP, PRA and ET-1 were elevated compared to healthy subjects. Exercise induced an increase in ANP, A and NA in both CHF patients and in normal subjects, however BNP was only increased in CHF patients and not in normal subjects. When CHF patients exercise at the same relative and submaximal level as age-matched healthy subjects, the relative increases in ANP, A and NA were similar, however, BNP levels only increased in the CHF group. | {
"pile_set_name": "PubMed Abstracts"
} |
Regulation of gene expression in melanoma: new approaches for treatment.
The molecular changes associated with the transition of melanoma cells from radial growth phase (RGP) to vertical growth phase (VGP, metastatic phenotype) are not yet well defined. We have demonstrated that the progression of human melanoma is associated with loss of expression of the transcription factor AP-2. In metastatic melanoma cells, this loss resulted in overexpression of MCAM/MUC18, MMP-2, the thrombin receptor (PAR-1), and lack of c-KIT expression. The transition from RGP to VGP is also associated with overexpression of the angiogenic factor IL-8. Additionally, the transition of melanoma cells from RGP to VGP is associated with overexpression of the transcription factors CREB and ATF-1, both of which may act as survival factors for human melanoma cells. Inactivation of CREB/ATF-1 activities in metastatic melanoma cells by dominant-negative CREB or by anti-ATF-1 single chain antibody fragment (ScFv), resulted in deregulation of MMP-2 and MCAM/MUC18, increased the sensitivity of melanoma cells to apoptosis, and inhibition of their tumorigenicity and metastatic potential in vivo. In this prospect article, we summarize our data on the role of AP-2 and CREB/ATF-1 in the progression of human melanoma and report on the development of new fully human antibodies anti-MCAM/MUC18 and anti-IL-8 which could serve as new modalities for the treatment of melanoma. | {
"pile_set_name": "PubMed Abstracts"
} |
Surgical site infection rates following cardiac surgery: the impact of a 6-year infection control program.
To evaluate the impact of an infection control program on surgical site infections (SSIs) complicating cardiac operations. Prospective cohort study of patients undergoing cardiac operations. Interventions included prospective surveillance, povidone-iodine scrub showers, depilation before surgery, administration of preoperative antibiotic prophylaxis in the operating room, and postdischarge follow-up. Logistic regression models were fitted to assess infection rates over time, adjusting for factors known to affect SSI rates. The overall SSI rate for 2051 procedures was 10.4%. Rates of superficial and deep incisional SSIs remained unchanged over the study period. The rates of all organ/space infections, mediastinitis, and SSIs because of methicillin-resistant Staphylococcus aureus during the first 2 years were 3.25%, 2.22%, and 1.48%, respectively, and they decreased to 1.17%, 0.73%, and 0.73%, respectively, by the end of 2002 (P = .01, P = .01, and P = .09, respectively). The adjusted odds ratios for these 3 types of infection at the end of 2002 compared with December 31, 1998, were 0.19 (95% confidence interval [95% CI]: 0.07-0.48), 0.20 (95% CI: 0.06-0.66), and 0.28 (95% CI: 0.08-0.97), respectively. We observed significant reductions in organ/space infection rates, particularly mediastinitis. These differences remained significant when adjusted for potential confounding variables. | {
"pile_set_name": "PubMed Abstracts"
} |
Effects of a HP0859 (rfaD) knockout mutation on lipopolysaccharide structure of Helicobacter pylori 26695 and the bacterial adhesion on AGS cells.
Lipopolysaccharide (LPS) is considered as an important virulence factor of Helicobacter pylori, and contributes to infection persistence and disease severity. ADP-L-glycero-D-manno-heptose-6-epimerase is an enzyme essential for LPS synthesis and understanding of its biochemistry is critical for drug development. We cloned one putative ortholog of Escherichia colirfaD, HP0859, from H. pylori 26695. Determination of the native molecular weight of the recombinant HP0859 protein suggests that the protein is likely a hexamer. NADP+, instead of NAD+, was proved to be the physiological cofactor for HP0859 protein. Circular dichroism spectrum analysis demonstrated that the secondary structure of this protein is significantly altered when the cofactor is removed. We also constructed an HP0859 knockout mutant and examined its phenotypic properties. The HP0859 knockout mutant exhibited a severe truncation of LPS, a decreased growth rate, and a higher susceptibility to novobiocin. Disruption of HP0859 also reduced the adhesive capacity of H. pylori to AGS cells, and the infected cells failed to display the classic hummingbird phenotype. Complementation of the HP0859 knockout mutation restored these phenotypes completely. In conclusion, we demonstrate that HP0859 codes for a protein essential for the LPS inner core biosynthesis in H. pylori and an intact LPS structure contributes to the adherence ability of this bacterium. | {
"pile_set_name": "PubMed Abstracts"
} |
Validity study of a new diagnostic scale for drug-induced liver injury in Japan-comparison with two previous scales.
There are no specific diagnostic markers for drug-induced liver injury (DILI), a disease that is unpredictable and occasionally fatal. A new diagnostic scale, the DDW-J scale, was recently proposed in Japan, by modifying the International Consensus Meeting (ICM) scale in the items concerning chronologic criteria, concomitant drug(s), and extrahepatic manifestations. In order to determine the validity of the DDW-J scale, we assessed 127 patients (81 patients with DILI and 46 control patients) received a total of 423 drugs. When patients were assessed as 'highly probable' or 'probable', the DDW-J scale had higher sensitivity and slightly lowers specificity than the ICM scale (93.8% versus 77.8% and 89.1% versus 100%). The DDW-J scale was able to accurately diagnose DILI in some cases that were overlooked using the ICM scale. While the weighted statistical test indicated a poor correlation between the ICM and the DDW-J scales, receiver operating characteristic curves revealed that these two were superior to the Maria and Victorino scale. Future work still must be done using statistical evidence to refine the weights of individual parameters. However, the results from our study indicate that the DDW-J scale is a powerful tool with potentially important clinical applications in the diagnosis of DILI. | {
"pile_set_name": "PubMed Abstracts"
} |
Formation of autocrine loops in human cerebral meningioma tissue by leukemia inhibitor factor, interleukin-6, and oncostatin M: inhibition of meningioma cell growth in vitro by recombinant oncostatin M.
It has been demonstrated that growth of cerebral meningiomas found in humans is controlled by a variety of factors, including growth factors, aminergic agents, neuropeptides, and steroids. To further our knowledge of this process, the authors investigated the presence and function of the cytokines leukemia inhibitory factor (LIF), interleukin-6 (IL-6), and oncostatin M (OSM) on meningioma cell proliferation. Active transcription of LIF, IL-6, and OSM, their related receptors (LIF-R, IL-6-R, and gp130), and the consecutive signal-transducing molecules (STAT 1, STAT 3, and STAT 5a) were analyzed in reverse transcriptase-polymerase chain reaction experiments. The presence of endogenous LIF, IL-6, and OSM proteins was demonstrated in the supernatant of cultured meningioma cells using the enzyme-linked immunosorbent assay and Western blot experiments, thus indicating an autocrine signaling pathway for all three cytokines. The biological function of all three cytokines was evaluated by studying their effects on meningioma cell growth. Recombinant LIF and IL-6 showed no significant growth modulating effects; however, recombinant OSM decreased meningioma cell growth by 66%. The antiproliferative potency of OSM was demonstrated by cell count experiments, the [3H]thymidine incorporation assay, and cell cycle analysis. These in vitro data support the concept that growth of meningioma cells may be modulated by cytokines, and they also indicate that recombinant OSM may be one future candidate for use in the adjuvant treatment of inoperable and recurrent meningiomas. | {
"pile_set_name": "PubMed Abstracts"
} |
Presence of Histamine in the Bluefish, Pomatomus saltatrix.
Consumption of bluefish ( Pomatomus saltatrix ) has been epidemiologically implicated and confirmed by laboratory analyses as a cause of scombroid food poisoning. An examination of marketable bluefish filets in the State of Connecticut found over 6.5% of the filets had histamine levels indicative of decomposition. No direct correlation of the presence of histidine decarboxylating bacteria and levels of histamine was found. The bluefish should be recognized as a food capable of causing scombroid poisoning. | {
"pile_set_name": "PubMed Abstracts"
} |
A fine LINE-1 in mouse embryonic chromatin regulation.
The functional role of repetitive elements in mammalian genomes is still largely unexplored. A new study provides evidence that LINE-1 retrotransposons regulate chromatin dynamics and are essential for normal embryonic development in mice. | {
"pile_set_name": "PubMed Abstracts"
} |
[Spinal cord injury by a broken acupuncture needle--a case report].
Acupuncture has been widely performed for the treatment of many different disorders in Japan. Several complications of acupuncture such as pneumothorax, cardiac tamponade, serum hepatitis have been reported. Accidentally broken needle is also one of the causes of complications of acupuncture. Usually it produces little problem, but may cause spinal cord injury, as presented by this report. The patient was a 49-year-old man who received an acupuncture procedure in his left nuchal region for shoulder pain. During acupuncture the needle was accidentally broken. The needle was tried to be removed by a surgeon on the same day but it could not be found. He was seen at our hospital with no neurological deficit 3 month later. Plain X-ray films and CT scan revealed a 4 cm long needle between C2 and C3 vertebrae penetrating into the cord. The needle was removed to prevent the possible neurological deficit which might be produced by the moving needle. The operative procedure was done under operating microscope with the aids of X-ray monitoring and injected dye. The direction to reach the tail of the broken needle is most important for avoiding further spinal cord injury during procedure. The post-operative course of the patient was uneventful and he was discharged with no deficit. | {
"pile_set_name": "PubMed Abstracts"
} |
The adverse mental health of carers: Does the patient diagnosis play a role?
The adverse mental health effects of caring have been studied, frequently in carers of people with dementia. Less is known about the mental health of carers of people with other conditions. This study compared depression and burden in older carers looking after people with a variety of conditions. Over 200 older carers interested in participating in the Improving Mood through Physical Activity in Carers and Care-recipient Trial were included in this cross-sectional study, using the Geriatric Depression Scale (GDS) and Zarit Burden Inventory (ZBI). Overall there were 43% of carers who were depressed and a quarter of them reported moderate-to-severe burden. Carers of people with physical conditions had the highest levels of depression and burden. Patient diagnosis, hours spent caring, and burden were associated with depression, while hours spent caring and carer depression were associated with burden. These factors contributed approximately 25-30% of the variance of depression and burden, respectively. The diagnosis of the patient was a factor associated with depression, and older carers of people with physical conditions were at the highest risk. It is important for clinicians to assess the mental health of all carers, regardless of the patient diagnosis. | {
"pile_set_name": "PubMed Abstracts"
} |
Comparison of mechanical properties of rat tibialis anterior tendon evaluated using two different approaches.
Tendon injuries may result in variations of its mechanical properties. The published data of the tendon stiffness of small animals, such as mouse and rat, are exclusively obtained by measuring grip-to-grip (g-t-g) displacement. Local strain concentration and relative sliding of the specimens in the clamps might significantly affect the measured tendon deformation. In the present study, the mechanical properties of the rat tibialis anterior tendon measured using the proposed tendon mark method were compared to those evaluated using the g-t-g displacement method. Five male Sprague Dawley rats ( approximately 418 g) were used in this study. For the proposed method, reference marks were made on the tendons using permanent ink. A microscope video system was customized to observe and record the tendon deformation. Pattern recognition software was developed to obtain the displacement time-histories of the reference marks. The distance between the grips was approximately 7 mm; and the distance between the reference marks used for the data processing was approximately 5 mm. The cross-section areas of the specimens were measured using a custom-made slot gauge and by applying a constant compressive stress (0.15 MPa). The tendons were clamped between two custom-made metal grips and stretched on a testing machine at a constant speed (1 mm/s) up to failure. Throughout the tests, the tendon specimens were submerged in a PBS bath at 22 degrees C. The deformation of the specimens was evaluated using the g-t-g displacement method and the proposed method. The stress/strain curves obtained by using the g-t-g displacement can be characterized by an initial toe zone, a quasi-linear zone, and a final failure stage. The stress/strain curves determined using the proposed method are quite different from those obtained using the g-t-g displacement: it has a smaller toe zone and a stress-hardening transition, over which the tendon stiffness increases dramatically with the increasing strain. The tendon stiffness measured by using the g-t-g displacement method may underestimate the actual mechanical properties of tendon by approximately 43%. | {
"pile_set_name": "PubMed Abstracts"
} |
Analysis of the environmental factors for microcellular systems in urban areas.
In this study some general guidelines to be used for the installation of microcellular base stations in order to guarantee exposure levels have been identified. A detailed analysis of field strength levels around realistic urban microcellular antennae has been performed by means of experimental and theoretical evaluations as a function of antenna type and the characteristics of the surrounding environment. | {
"pile_set_name": "PubMed Abstracts"
} |
Autoaggregating Yersinia enterocolitica express surface fimbriae with high surface hydrophobicity.
For 13 strains of Yersinia enterocolitica, there was a good correlation between the production of the broad-spectrum, mannose-resistant Yersinia haemagglutinin (MR/Y HA), the presence of fimbriae and high surface hydrophobicity. Each of these characters was expressed in cultures grown at low (less than 32 degrees C) but not at high (Greater than 35 degrees C) temperatures. | {
"pile_set_name": "PubMed Abstracts"
} |
[Effect of childhood physical and emotional abuse on psychological health in undergraduate students].
To study the effect of childhood physical and emotional abuse on psychological health in undergraduate students. A questionnaire investigation (Bernstein, revised) on childhood abuse history was performed in 1 200 undergraduate students in Xi'an. Their psychological states were assessed by Symptom Check List-90. Six hundred and sixty-eight students (55.7%) had physical and emotional abuse experiences, including humiliation, corporal punishment, beating or activity confinement, before 16 years old. Twenty-one percent of the 1 200 students experienced beating, even serious beating with equipment. The students who experienced serious physical and emotional abuse during childhood were more prone to the development of somatization symptoms, obsession, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety and paranoia than those students without abuse experiences. Childhood physical and emotional abuse is common in China and this may adversely affect the psychological health of undergraduate students who have experienced it. | {
"pile_set_name": "PubMed Abstracts"
} |
Effect of Saffron (Crocus sativus) on neurobehavioral and neurochemical changes in cerebral ischemia in rats.
The modifying effects of Crocus sativus (CS) stigma extract on neurobehavioral activities, malondialdehyde (MDA), reduced glutathione (GSH), glutathione peroxidase, glutathione reductase, glutathione S-transferase, superoxide dismutase (SOD), catalase (CAT), and Na(+),K(+)-ATPase activities, and glutamate (Glu) and aspartate (Asp) content were examined in the middle cerebral artery (MCA) occlusion (MCAO) model of acute cerebral ischemia in rats. The right MCA of male Wistar rats was occluded for 2 hours using intraluminal 4-0 monofilament, and reperfusion was allowed for 22 hours. MCAO caused significant depletion in the contents of GSH and its dependent enzymes while significant elevation of MDA, Glu, and Asp. The activities of Na(+),K(+)-ATPase, SOD, and CAT were decreased significantly by MCAO. The neurobehavioral activities (grip strength, spontaneous motor activity, and motor coordination) were also decreased significantly in the MCAO group. All the alterations induced by ischemia were significantly attenuated by pretreatment of CS (100 mg/kg of body weight, p.o.) 7 days before the induction of MCAO and correlated well with histopathology by decreasing the neuronal cell death following MCAO and reperfusion. The present results may suggest the effectiveness of CS in focal ischemia most probably by virtue of its antioxidant property. | {
"pile_set_name": "PubMed Abstracts"
} |
Patient-derived xenografts as tools in pharmaceutical development.
Successful drug development in oncology is grossly suboptimal, manifested by the very low percentage of new agents being developed that ultimately succeed in clinical approval. This poor success is in part due to the inability of standard cell-line xenograft models to accurately predict clinical success and to tailor chemotherapy specifically to a group of patients more likely to benefit from the therapy. Patient-derived xenografts (PDXs) maintain the histopathological architecture and molecular features of human tumors, and offer a potential solution to maximize drug development success and ultimately generate better outcomes for patients. Although imperfect in mimicking all aspects of human cancer, PDXs are a more predictable platform for preclinical evaluation of treatment effect and in selected cases can guide therapeutic decision making in the clinic. This article summarizes the current status of PDX models, challenges associated with modeling human cancer, and various approaches that have been applied to overcome these challenges and improve the clinical relevance of PDX cancer models. | {
"pile_set_name": "PubMed Abstracts"
} |
Adsorption of SDS and PEG on calcium fluoride studied by sum frequency generation vibrational spectroscopy.
The adsorption of sodium dodecyl sulfate (SDS) from aqueous solution onto a calcium fluoride substrate (CaF(2)), in the presence of polyethylene glycol (PEG) of different molecular weights, has been investigated using the interface specific nonlinear optical technique of sum frequency generation (SFG) vibrational spectroscopy. Spectra of adsorbed SDS (in the C-H stretching region) were recorded at the surface of a CaF(2) prism in contact with SDS solutions at concentrations up to the cmc (8 mM) of the pure surfactant and in contact with binary solutions containing SDS and PEG with molecular weights from 400 to 12 000. In contrast with SFG spectra from the same combinations of surfactant and polymer on a hydrophobic surface, there was no evidence of spectra arising from the actual polymer adsorbed on CaF(2) at any polymer molecular weight either in the absence or presence of surfactant. However, there was indirect evidence for the presence of adsorbed polymer from changes in the SDS SFG spectra in the presence of polymer compared with spectra when the polymer was absent. The SFG spectra of SDS at 0.8 mM were closely similar to each other at all polymer molecular weights and different from the spectra in the absence of the polymer. The spectral differences between the polymer present and polymer absent was much smaller when the solution concentration of surfactant was 8 mM. | {
"pile_set_name": "PubMed Abstracts"
} |
Bacterial expression of functional, biotinylated peripheral cannabinoid receptor CB2.
A biotin-protein ligase recognition site (BRS) was inserted into a polypeptide comprised of the maltose-binding protein, the peripheral cannabinoid receptor (CB2), thioredoxin A, and a polyhistidine tag at the carboxy terminus. Expression levels of the recombinant receptor in Escherichia coli BL21(DE3) cells were approximately 1mg per liter of bacterial culture. The biotinylated CB2-fusion fully retained its ligand-binding capacity. Introduction of the BRS at the C-terminus of the CB2 fusion protein (construct CB2-109) resulted in its complete in vivo biotinylation; the biotinylated protein was streptavidin-binding competent. Positioning of the BRS near the N-terminus of CB2 (CB2-112) resulted in a very low level of biotinylation in vivo. However, the detergent solubilized and purified CB2-112 fusion protein were successfully biotinylated in vitro by action of a BirA biotin-protein ligase. The biotinylated CB2-112 fusion protein was cleaved by the tobacco etch virus protease at specifically inserted sites, and deposited onto monomeric avidin agarose beads. Biotinylation of the recombinant CB2 receptor enabled not only purification but also immobilization of the GPCR on a solid support in homogeneous orientation which is beneficial for subsequent structural characterization. | {
"pile_set_name": "PubMed Abstracts"
} |
The phenomenon of travelling waves: a review.
As early as 1934 evidence appeared in animals that waves of activity do not always remain stationary but can actually spread over the whole cortex. In the next year some of the earliest studies on the EEG of man showed phase changes of alpha activity that could account for the TW, which later was described when apparatus was built to better view it, especially in the 1950s. The TW has been described mainly as alpha activity that appears to travel both in abnormal and also normal conditions, including the resting state. The phenomenon seems to be enhanced with either external stimuli or endogenous emotional states, which increase phase changes on different brain areas. The travel has been described in all directions from the frontal to the occipital pole, and early work suggests that the posterior-anterior direction may be more often found in abnormal mental states. The speed of travelling over the scalp has varied usually from 1-20 m/sec, but generally has been reported around 5 m/sec. Most investigators have reported that the positive phase is the one which most clearly travels. In exploring the phenomenon of the travelling wave, it is clear that maximal positivity and negativity of the alpha is not always on the occipital regions, as many clinical studies would imply; instead, the fronto-central areas in particular are often the focus of maximal alpha.(ABSTRACT TRUNCATED AT 250 WORDS) | {
"pile_set_name": "PubMed Abstracts"
} |
Inhibitory effect of oral Lactobacillus against oral pathogens.
To determine the inhibitory effect of oral Lactobacillus against putative oral pathogens. Total 357 strains comprising 10 species of oral Lactobacillus, Lactobacillus fermentum (195), Lactobacillus salivarius (53), Lactobacillus casei (20), Lactobacillus gasseri (18), Lactobacillus rhamnosus (14), Lactobacillus paracasei (12), Lactobacillus mucosae (12), Lactobacillus oris (12), Lactobacillus plantarum (11) and Lactobacillus vaginalis (10) were used as producer strains. Inhibitory effect against a panel of indicators, periodontitis- and caries-related pathogens, was assessed. Most oral Lactobacillus was able to inhibit the growth of both periodontitis- and caries-related pathogens. The strongest inhibitory activity was associated with Lact. paracasei, Lact. plantarum, Lact. rhamnosus, Lact. casei and Lact. salivarius. Lactobacillus SD1-SD6, representing the six species with the strong inhibitory effect, inhibited growth of Streptococcus mutans ATCC 25175 in the biofilm model. Also, it was demonstrated that growth of Strep. mutans was inhibited in a mixture with Lact. paracasei SD1. The inhibition was enhanced in acidic condition and 5% glucose. The results have shown that oral Lactobacillus SD1-SD6 showed a strong inhibitory effect against Strep. mutans and Streptococcus sobrinus, as well as, Gram-negative periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. The results indicated that Lactobacillus may be of benefit as probiotics for the prevention of oral diseases. | {
"pile_set_name": "PubMed Abstracts"
} |
The evaluation of bond strength of a composite and a compomer to white mineral trioxide aggregate with two different bonding systems.
The purpose of this study was to evaluate the bond strength of a resin composite and a polyacid modified composite or "compomer" to white mineral trioxide aggregate (WMTA) with two different bonding systems (total-etch one bottle and self-etch one step). Forty specimens of WMTA were prepared and divided into four groups. In group one, Single Bond (3M/ESPE, St Paul, MN) and Z250 (3M/ESPE) were placed over WMTA. In group two, Prompt L-Pop (3M Dental Products, St Paul, MN) and Z250 were applied. In group three, Single Bond was applied with Dyract AP (Dentsply DeTrey, Konstanz, Germany), and, in group four, Prompt L-Pop was applied with Dyract AP. The shear bond strength was measured, and the fractured surfaces were examined. The results of the shear bond strength tests were analyzed by one-way analysis of variance test. The results of this study have suggested that the total-etch one-bottle adhesive system mediated a stronger bond to WMTA for both the resin composite and the compomer investigated. The placement of composite (Z250) and compomer materials (Dyract AP), used with total-etch one-bottle adhesive (Single Bond), over WMTA as final restoration may be appropriate. | {
"pile_set_name": "PubMed Abstracts"
} |
A wavelet-based approach for time series pattern detection and events prediction applied to telemonitoring data.
This work aims the development of a predictive strategy able to estimate future events with relevant impact in the cardiovascular status. Based on wavelet transform, a new time series similarity metric is introduced, which is capable to detect a pre-defined pattern in time series data. In addition, a methodology combining a wavelet scheme with state space multi-models is proposed to achieve the prediction of future signal values. Blood pressure signals, collected by a telemonitoring platform (TEN-HMS), are used to detect the occurrence of future hypertension events. | {
"pile_set_name": "PubMed Abstracts"
} |
Multi-drug resistance in a canine lymphoid cell line due to increased P-glycoprotein expression, a potential model for drug-resistant canine lymphoma.
Canine lymphoma is routinely treated with a doxorubicin-based multidrug chemotherapy protocol, and although treatment is initially successful, tumor recurrence is common and associated with therapy resistance. Active efflux of chemotherapeutic agents by transporter proteins of the ATP-Binding Cassette superfamily forms an effective cellular defense mechanism and a high expression of these transporters is frequently observed in chemotherapy-resistant tumors in both humans and dogs. In this study we describe the ABC-transporter expression in a canine lymphoid cell line and a sub-cell line with acquired drug resistance following prolonged exposure to doxorubicin. This sub-cell line was more resistant to doxorubicin and vincristine, but not to prednisolone, and had a highly increased P-glycoprotein (P-gp/abcb1) expression and transport capacity for the P-gp model-substrate rhodamine123. Both resistance to doxorubicin and vincristine, and rhodamine123 transport capacity were fully reversed by the P-gp inhibitor PSC833. No changes were observed in the expression and function of the ABC-transporters MRP-1 and BCRP. It is concluded that GL-40 cells represent a useful model for studying P-gp dependent drug resistance in canine lymphoid neoplasia, and that this model can be used for screening substances as potential P-gp substrates and their capacity to modulate P-gp mediated drug resistance. | {
"pile_set_name": "PubMed Abstracts"
} |
[Ribavirin treatment in patients with chronic hepatitis C refractory to interferon-alpha].
Four patients with chronic hepatitis C who did not respond to treatment with alpha interferon were treated with oral ribavirin at a dose of 1.000-1.200 mg/day for 6 months. A marked, although transitory, decrease was observed in the transaminase values which returned to pre-treatment values on termination of the same. Normal transaminase values were only obtained at some point in the treatment in two patients. Ribavirin was well tolerated with very slight anemia being detected in all the cases. These results, which are superposable to those of other authors who have studied the effects of this antiviral agent in chronic hepatitis C, suggest that ribavirin may play a role in the treatment of this disease. Given the existing data, this role would be one of a drug associated with interferon with which it may have a synergic action rather than as a monotherapy. | {
"pile_set_name": "PubMed Abstracts"
} |
Validity of an artificial neural network in predicting discharge destination from a postacute geriatric rehabilitation unit.
To develop an artificial neural network (ANN) designed to predict discharge destination from postacute geriatric rehabilitation units. Nonconcurrent prospective study. Postacute geriatric rehabilitation units: a 20-bed unit in a nonproprietary skilled nursing facility and a 40-bed unit in a suburban private facility. Consecutive sample of 661 patients admitted between January 1995 and February 1999, including a derivation group of 452 patients and a validation group of 209 patients. A feed-forward, back-propagation neural network to predict discharge destination. Discharge destination from postacute geriatric rehabilitation. An ANN was trained on clinical pattern set derived from 452 patients and validated prospectively on 209 consecutive patients admitted to postacute geriatric rehabilitation units. The neural network achieved a sensitivity of 85.7% (95% confidence interval [CI], 83.7-89.4) and specificity of 94.1% (95% CI, 84.4-99.1) in identifying discharge destination with a corresponding area under the curve of 95.7% (95% CI, 92.1-98.3). An ANN can predict discharge to the community postacute rehabilitation with a high degree of accuracy. It could have particular value to predict return to the community for older adults with multiple comorbidities after an acute hospitalization. | {
"pile_set_name": "PubMed Abstracts"
} |
Skin Cancer Following Solid Organ Transplantation: A Review of Risk Factors and Models of Care.
The number of solid organ transplants has been increasing annually worldwide. Advances in transplantation surgery and community awareness of organ donation have been key contributors. Combined with increased understanding of immunosuppression, there are a growing number of solid organ transplant recipients in the community as a result of improved long-term outcomes. There remains a high incidence of deaths worldwide post-transplant due to non-melanoma skin cancer (NMSC), which has greater morbidity and mortality in this population than in the general community. Many transplant candidates are not screened prior to organ transplantation and not followed up dermatologically after transplant. After a comprehensive review of the MEDLINE database, we present an update of literature on risk factors for melanoma and non-melanoma skin cancer development in transplant recipients. Medications used by transplant recipients, including immunosuppressants and antibiotics, are discussed along with their respective risks of skin cancer development. We conclude with evidence-based recommendations for models of care, including patient education and dermatological review of transplant recipients. | {
"pile_set_name": "PubMed Abstracts"
} |
The role of nitric oxide pathway in the renal ischemia-reperfusion injury in rats.
Nitric oxide (NO), synthesized from L-arginine by the enzyme nitric oxide synthase (NOS), seems to play an ambiguous role during tissue ischemia-reperfusion injury. Our objective was to evaluate the effects of L-arginine, a NO donor, and N(G)-nitro-L-arginine-methylester (L-NAME), a NOS inhibitor, on oxidative stress, renal dysfunction, histologic alterations and surgical mortality rate induced by renal ischemia-reperfusion (RIR) in uninephrectomized rats. One-hundred and ninety-seven Wistar rats were randomized into five experimental groups. Group 1: sham operation; group 2: right uninephrectomy (UNI); group 3: UNI + RIR in the contralateral kidney; group 4: UNI + L-NAME (20 mg/kg; intraperitoneally) + RIR; and group 5: UNI + L-arginine + RIR. The effect of the drugs was evaluated by lipid peroxidation measured by the renal malondialdehyde (MD) content and chemiluminescence (CL) levels, serum creatinine (Cr) levels, urinary volume, tubular necrosis and athrophy, inflammatory infiltrate, interstitial fibrosis as histologic evaluation and surgical mortality rate after the procedures. A P value less than 0.05 was considered significant. Right uninephrectomy did not alter the renal parameters. RIR increased Cr levels (at 24 and 96 h of reperfusion), index of lipid peroxidation (both MD and QL levels), and worsened the histologic aspects. Pretreatment with L-arginine reduced the kidney levels of QL when compared with the non-treated group (5574 +/- 909 vs. 13 660 +/- 1104 cps/mg of protein; P < 0.05) but increased the MD levels (0.97 +/- 0.24 vs. 0.79 +/- 0.06 nmol/mg of protein; P < 0.05). Moreover, L-arginine attenuated the increment of Cr levels, inflammatory infiltrate and tubular athrophy in rats subjected to RIR (P < 0.05). On the other hand, pretreatment with L-NAME increased both CL (17 482 +/- 4397 vs. 13 660 +/- 1104 cps/mg of protein; P < 0.05) and MD levels (1.16 +/- 0.11 vs. 0.79 +/- 0.06 nmol/mg of protein; P < 0.05). Furthermore, L-NAME worsened the renal dysfunction (P < 0.05) at 192 h after the RIR, and surgical mortality rates were similar (P > 0.05). L-arginine has a tendency to exert a beneficial effect on renal damage during RIR in rats. Moreover, L-NAME seems to worsen the renal damage by increasing the kidney-levels of CL and impairment of renal function probably due to reduction of NO production. | {
"pile_set_name": "PubMed Abstracts"
} |
Anti-inflammatory effects of topical ocular MAXIDEX administration to rabbits following vitrectomy or lensectomy.
We conducted a series of surgical studies (n=155) to find out the possible utility of the Dutch Belted rabbits as an ocular test model. Following either vitrectomy (n=59) or lensectomy (n=96) studies using either BSS or BSS Plus, we characterized the corresponding magnitude and duration of inflammatory response of selected endpoints over a one-week period. Preoperative Dutch Belted rabbits served as controls for baseline determination (n=27). Inflammatory endpoints included clinical inflammation, blood aqueous barrier (BAB) changes measured by particle-scatter and fluorophotometry, corneal edema, and prostaglandin-E2 (PGE2). Topical ocular 0.1% dexamethasone (MAXIDEX) served as a positive treatment group. We compared the inflammatory features (treated and untreated) to determine significance. Using either irrigating solution, the endpoints (n=101) were shown increased in both models. While the clinical scores were similar following both types of surgery (ns; p=0.51), the lensectomy study caused a more marked effect on corneal edema (p=0.0004) and PGE2 production (p=0.002) compared with the vitrectomy study. After the lensectomy procedure, BSS Plus (n=52) compared with BSS (n=24) showed a significant improvement (p=0.004) of clinical score during the recovery phase. Further improvement was gained over BSS Plus (n=52) using MAXIDEX treatment. Topical MAXIDEX (lensectomy, n=20/group; vitrectomy, n=12/group) reduced clinical score (p<0.001), decreased BAB breakdown to fluorescein (p<0.01), lessened particle flare (p<0.05), inhibited aqueous PGE2 levels (p<0.001), and reduced corneal edema (p=0.01) in the lensectomy group. The use of the rabbit model offers a convenient test to identify therapeutic agents that could lessen ocular complications after these common ocular surgeries. | {
"pile_set_name": "PubMed Abstracts"
} |
IgG allotypes and subclasses in Norwegian patients with multiple sclerosis.
Multiple sclerosis (MS) is a multifactorial disease in which genetic and environmental factors apparently have a major influence on the susceptibility and course of the disease. In the present study we have investigated the genetic basis and subclass levels of IgG in MS. Hundred and thirty-six Norwegian patients with MS and 92 controls were genotyped for IgG allotypes of the GM and KM systems. IgG and IgG subclasses were quantified in sera from 115 MS patients and 20 controls. Neither GM nor KM allo-, haplo- or genotypes were significantly correlated with susceptibility, severity or course of the disease. The G1M (3) (3), G2M (23) (23) and G3M (5) (5) allotypes were significantly correlated with high serum levels of IgG3, whereas high IgG2 levels were correlated with G1M (3) (3) and G2M (23) (23) in both patients and controls. Serum levels of IgG subclasses were not significantly correlated with course or severity of the disease. The results indicate no major role for IgG allotypes or IgG subclass levels in the pathogenesis of MS. | {
"pile_set_name": "PubMed Abstracts"
} |
Assignment of simian rotavirus SA11 temperature-sensitive mutant groups B and E to genome segments.
Recombinant (reassortant) viruses were selected from crosses between temperature-sensitive (ts) mutants of simian rotavirus SA11 and wild-type human rotavirus Wa. The double-stranded genome RNAs of the reassortants were examined by electrophoresis in Tris-glycine-buffered polyacrylamide gels and by dot hybridization with a cloned DNA probe for genome segment 2. Analysis of replacements of genome segments in the reassortants allowed construction of a map correlating genome segments providing functions interchangeable between SA11 and Wa. The reassortants revealed a functional correspondence in order of increasing electrophoretic mobility of genome segments. Analysis of the parental origin of genome segments in ts+ SA11/Wa reassortants derived from the crosses SA11 tsB(339) X Wa and SA11 tsE(1400) X Wa revealed that the group B lesion of tsB(339) was located on genome segment 3 and the group E lesion of tsE(1400) was on segment 8. | {
"pile_set_name": "PubMed Abstracts"
} |
Field theory of directed percolation with long-range spreading.
It is well established that the phase transition between survival and extinction in spreading models with short-range interactions is generically associated with the directed percolation (DP) universality class. In many realistic spreading processes, however, interactions are long ranged and well described by Lévy flights-i.e., by a probability distribution that decays in d dimensions with distance r as r;{-d-sigma} . We employ the powerful methods of renormalized field theory to study DP with such long-range Lévy-flight spreading in some depth. Our results unambiguously corroborate earlier findings that there are four renormalization group fixed points corresponding to, respectively, short-range Gaussian, Lévy Gaussian, short-range, and Lévy DP and that there are four lines in the (sigma,d) plane which separate the stability regions of these fixed points. When the stability line between short-range DP and Lévy DP is crossed, all critical exponents change continuously. We calculate the exponents describing Lévy DP to second order in an epsilon expansion, and we compare our analytical results to the results of existing numerical simulations. Furthermore, we calculate the leading logarithmic corrections for several dynamical observables. | {
"pile_set_name": "PubMed Abstracts"
} |
Overlapping features between social anxiety and obsessive-compulsive spectrum in a clinical sample and in healthy controls: toward an integrative model.
While the literature frequently highlighted an association between social anxiety disorder (SAD) and obsessive-compulsive disorder (OCD), few studies investigated the overlapping features of these conditions. The presented work evaluated the relationship between SAD and OCD spectrum in a clinical population and in healthy controls (HC). Fifty-six patients with OCD, 51 with SAD, 43 with major depressive disorder (MDD), and 59 HC (N = 209) were assessed using the Mini International Neuropsychiatric Interview, the Social Phobia Spectrum (SCI-SHY), and the Obsessive-Compulsive Spectrum (SCI-OBS). SAD patients scored significantly higher than other groups on all SCI-SHY domains and total score; OCD patients scored significantly higher than HC. MDD patients scored significantly higher than HC on the SCI-SHY total, Behavioral inhibition, and Interpersonal sensitivity domains. OCD patients scored significantly higher than other groups on all SCI-OBS domains except Doubt, for which OCD and SAD scored equally high. SAD patients scored significantly higher than HC on the SCI-OBS total, Childhood/adolescence, Doubt, and Hypercontrol domains. MDD patients scored significantly higher than HC on the Hypercontrol domain. SCI-OBS and SCI-SHY were widely correlated among groups, although lower correlations were found among OCD patients. Stronger correlations were observed between SCI-SHY Interpersonal sensitivity and SCI-OBS Doubt, Obsessive-compulsive themes, and Hypercontrol; between SCI-SHY Specific anxieties/phobic features and SCI-OBS Obsessive-compulsive themes; and between SCI-SHY Behavioral inhibition and SCI-OBS Doubt, with slightly different patterns among groups. OCD and SAD spectrums widely overlap in clinical samples and in the general population. Interpersonal sensitivity and obsessive doubts might represent a common cognitive core for these conditions. | {
"pile_set_name": "PubMed Abstracts"
} |
Investigating the relationship between environmental factors and tick abundance in a small, highly heterogeneous region.
The tick Ixodes ricinus (L.) is the most important vector of tick-borne zoonoses in Europe. Apart from factors related to human behavior, tick abundance is a major driver of the incidence of tick-borne diseases in a given area and related data represent critical information for promoting effective public health policies. The present study analyzed the relationship between different environmental factors and tick abundance in order to improve the understanding of I. ricinus autecology and develop spatial predictive models that can be implemented in tick-borne disease prevention strategies. Ticks were sampled in 27 sites over a four-year period and different environmental variables were studied. Five simple models were developed that explain a large part of variation in tick abundance. Precipitation seems to play the most important role, followed by temperature, woodland coverage, and solar radiation. Model equations obtained in this study may enable the spatial interpolation and extension of tick abundance predicted values to sites of the same area, in order to build regional predictive maps. They could also be useful for the validation of large-scale spatial predictive maps. | {
"pile_set_name": "PubMed Abstracts"
} |
[Activation of complement and serial changes of anaphylatoxin (C3a, C5a) in patients for open-heart surgery using a membrane oxygenator].
Activation of complement and serum changes in anaphylatoxin (C3a and C5a) were studied in 8 patients who underwent open-heart surgery using a membrane oxygenator. C1 esterase inhibitor (C1-EI), C3, C5, CH50, C3a and C5a were measured serially at 7 points. C1-EI, C3, and C5 were measured by single radial immunodiffusion, CH50 by Mayer's method, and C3a and C5a by radioimmunoassay. Levels of C1-EI, C3 and C5 decreased significantly from 10 min after initiation to 120 min after the end of CPB compared with base line values. Degree of activation of complement increased in proportion to duration of CPB. Significant decreases of C3 and C5 continued until first postoperative day. Level of C3a increased significantly 10 min after initiation of CPB, and gradually increased till immediately after the end of CPB, when the level was maximum (4625 +/- 560 ng.ml-1) among 7 points. Level of C3a decreased gradually till 120 min after end of CPB. C5a was not detected during whole course. No patient showed respiratory distress of pulmonary edema. In conclusion, membrane oxygenator activated classical pathway of complement at 10 min after initiation of CPB. C3a increased significantly from 10 min after initiation of CPB to 120 min after end of CPB, but C5a was not detected at all during the whole course. The significant activation of complement continued till first postoperative day. | {
"pile_set_name": "PubMed Abstracts"
} |
Honeybee navigation en route to the goal: visual flight control and odometry
Recent research has uncovered a number of different ways in which bees use cues derived from optic flow for navigational purposes. The distance flown to a food source is gauged by integrating the apparent motion of the visual world that is experienced en route. In other words, bees possess a visually driven 'odometer' that is robust to variations in wind load and energy expenditure. Bees flying through a tunnel maintain equidistance to the flanking walls by balancing the apparent speeds of the images of the walls. This strategy enables them to negotiate narrow passages or to fly between obstacles. The speed of flight in a tunnel is controlled by holding constant the average image velocity as seen by the two eyes. This avoids potential collisions by ensuring that the bee slows down when flying through narrow passages. Bees landing on a horizontal surface hold constant the image velocity of the surface as they approach it. This automatically ensures that flight speed decreases with altitude and is close to zero at touchdown. The movement-sensitive mechanisms underlying these various behaviours seem to be different, qualitatively as well as quantitatively, from those mediating the well-investigated optomotor response. | {
"pile_set_name": "PubMed Abstracts"
} |
Photosynthesis is limited at high leaf to air vapor pressure deficit in a mutant of Arabidopsis thaliana that lacks trienoic fatty acids.
We have investigated the role of polyunsaturated fatty acids in photosynthesis using a triple mutant of Arabidopsis thaliana that lacks trienoic fatty acids (fad 3-2 fad 7-2 fad 8). Though this mutant is male sterile, vegetative growth and development under normal conditions are largely unaffected (McConn and Browse, 1996 Plant Cell 8: 403-416). At 0.2-1.0 kPa vapor pressure deficit (low VPD), maximum photosynthetic rates of wild-type and mutant plants were similar while stomatal conductance rates were up to 2 times higher in mutant plants. However, light-saturated rates of carbon assimilation and stomatal conductance in the mutant were lower than in wild-type plants when measured at ambient (35 Pa) CO(2) and 2.0-2.8 kPa vapor pressure deficit (high VPD). The limitation to photosynthesis in the mutant plants at high VPD was overcome by saturating partial pressures of CO(2) suggesting a stomatal limitation. Chlorophyll fluorescence measurements indicate that differences observed in maximum assimilation rates were not due to limitations within the photochemical reactions of photosynthesis. Stomatal response to VPD and intrinsic water use efficiency was drastically different in mutant versus wild-type plants. The results of this investigation indicate that for Arabidopsis, polyunsaturated fatty acids may be an important determinant of responses of photosynthesis and stomatal conductance to environmental stresses such as high VPD. | {
"pile_set_name": "PubMed Abstracts"
} |
Developmental, cognitive, and behavioral sequelae of child abuse.
There is growing interest in the neurologic, behavioral, and cognitive effects of child abuse and neglect. This article explores the literature on the short and long term sequelae of physically and sexually abused and neglected children, along with controversies generated by the studies themselves. Recommendations are made for swift and ongoing intervention in cases of child abuse to protect young victims from potentially devastating effects. | {
"pile_set_name": "PubMed Abstracts"
} |
The salience of facial expression for autistic children.
Autistic and non-autistic retarded children who were matched for verbal ability were shown 'standard' pairs of photographs of people who differed in three, two or one of the following respects: sex, age, facial expression of emotion, and the type of hat they were wearing. When given similar photographs to sort, the majority of non-autistic children sorted according to people's facial expressions before they sorted according to type of hat, but most autistic children gave priority to sorting by type of hat, and many neglected the facial expressions altogether. It is suggested that these results reflect autistic children's insensitivity to other people's facial expressions of emotion. | {
"pile_set_name": "PubMed Abstracts"
} |
A study of the development of fracture callus in the presence of an experimentally induced osteosarcoma.
The results of two experiments are reported in which the formation of an osteosarcoma was induced in mice by the intraosseous injection of Moloney's virus. In the first group of fifty mice, a complete diaphyseal fracture was carried out nine days later at the site of the tumour. In the second group of 200 mice, a partial fracture was produced at the time of injection so that immobilisation was assured. The effects of cyclophosphamide and calcitonin administration were also studied in this group. The course of the repair processes of the bone was studied in both groups, and showed that, even in the presence of an osteosarcoma, these begin and can reach completion, though obstructed and delayed by the tumour. | {
"pile_set_name": "PubMed Abstracts"
} |
Electrosynthesis of substituted 1H-indoles from o-nitrostyrenes.
A novel procedure has been devised for the synthesis of derivatives of 1H-indole that is based on the direct, room-temperature electrochemical reduction of substituted o-nitrostyrenes at carbon cathodes in N,N-dimethylformamide containing tetramethylammonium tetrafluoroborate as supporting electrolyte and in the presence of a 10-fold molar excess of a proton donor (phenol or methyl 3-oxobutanoate). | {
"pile_set_name": "PubMed Abstracts"
} |
Redistribution of fodrin in an in vitro wound healing model of the corneal epithelium.
We previously observed the redistribution of a membrane skeletal protein, fodrin, after wounding in the corneal epithelium in vivo. In this study, we made an in vitro wound healing model using cultured corneal epithelial cells to investigate the redistribution mechanism of fodrin in the corneal epithelial cells. The distributional change of fodrin from the plasmalemma to the cytoplasm was observed soon after wounding by indirect immunofluorescence microscopy and laser scanning confocal microscopy. A similar change was caused by treating intact cells with phorbol-12-myristate-13-acetate (PMA), but not with calcium ionophore, A23187. The redistribution occurred even in cells pretreated with 1,2-bis(O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetomethyl ester (BAPTA-AM) before wounding. The redistribution caused by wounding or by PMA was inhibited by pretreating the cells with protein kinase C inhibitors, H-7 or calphostin C. Moreover, the reagents were found to slow down the migration of corneal epithelial cells after wounding. These results suggest that the redistribution of fodrin in the wounded corneal epithelium is caused through the activation of protein kinase C and might be related to the ensuing cell migration. | {
"pile_set_name": "PubMed Abstracts"
} |
Detection of Stationary Foreground Objects Using Multiple Nonparametric Background-Foreground Models on a Finite State Machine.
There is a huge proliferation of surveillance systems that require strategies for detecting different kinds of stationary foreground objects (e.g., unattended packages or illegally parked vehicles). As these strategies must be able to detect foreground objects remaining static in crowd scenarios, regardless of how long they have not been moving, several algorithms for detecting different kinds of such foreground objects have been developed over the last decades. This paper presents an efficient and high-quality strategy to detect stationary foreground objects, which is able to detect not only completely static objects but also partially static ones. Three parallel nonparametric detectors with different absorption rates are used to detect currently moving foreground objects, short-term stationary foreground objects, and long-term stationary foreground objects. The results of the detectors are fed into a novel finite state machine that classifies the pixels among background, moving foreground objects, stationary foreground objects, occluded stationary foreground objects, and uncovered background. Results show that the proposed detection strategy is not only able to achieve high quality in several challenging situations but it also improves upon previous strategies. | {
"pile_set_name": "PubMed Abstracts"
} |
Acid-Base Catalysis in Glycosidations: A Nature Derived Alternative to the Generally Employed Methodology.
Inverting glycosyltransferases enforce in the active site an intramolecular, acid-base catalyzed glycosidation that, due to proximity of the donor anomeric carbon and the acceptor hydroxyl group, follows an SN2-type reaction. Spacers, tethering donor and acceptor via nonreacting functional groups, led in intramolecular glycosidations to excellent yields and, independent of the donor anomeric configuration, to either the α- or the β-anomer. The requirement of a demanding protecting group pattern confines the application of this efficient method. Only the method where the 2-hydroxyl group of a mannopyranosyl donor is tethered via an acetal spacer to the reacting acceptor functional group is used for β-mannopyranoside synthesis. The most elegant method, tethering donor and acceptor covalently to the spacer via the leaving group and the reacting functional group, was so far not as efficient as hoped. This method is very efficient when donor and acceptor are temporarily assembled through a hydrogen-bond facilitating a stretched hexagon-like transition state. This follows from the stereoselective O-glucopyranosyl trichloroacetimidate transformation into O-glucopyranosyl phosphate with dibenzyl phosphoric acid as acceptor that can be regarded as A═B-C-H acceptor type. Generalizing this concept to the use of alcohols as acceptors requires reversible generation of an A-B-C-H adduct where A-H represents the acceptor (RO-H) and B═C a catalyst that has to fulfill several criteria. Among these criteria are low affinity to nitrogen, avoiding glycosyl donor activation in the absence of acceptor, and high affinity to oxygen in order to generate the A-B-C-H adduct with increased proton acidity. Thus, hydrogen-bond mediated self-assembly of donor and acceptor and concomitant donor activation via a transition state is available, which enforces an acid-base catalyzed SN2-type reaction. It could be shown that PhBF2, Ph2BF, and PhSiF3 are such catalysts that fulfill the desired four functions: reversible adduct formation with the acceptor, hydrogen-bond mediated tethering of this adduct with the donor, and acid- and base-catalysis of the glycosidation. Also Lewis acidic metal salts, particularly the dimeric gold(III) chloride, turned out to exhibit excellent B═C type catalyst properties. Worth mentioning in this context is the ability of gold(III) chloride to regioselectively activate diols. As thioureas have high affinity to anions and also to neutral compounds through strong hydrogen bonds, their binding to alcohols and concomitant activation of O-glycosyl trichloroacetimidates was of interest. Yet, even the acidic N,N'-bis[3,5-bis(trifluoromethyl)phenyl]-thiourea was unable to catalyze glycosidations. However, as a cocatalyst to acids, thiourea exerts a strong effect that, based on NMR studies, leads first to a hydrogen-bond mediated catalyst-cocatalyst-acceptor complex. This complex activates the donor in an intramolecular, acid-base catalyzed reaction that is again closely related to the action of inverting glycosyltransferases. Thus, from O-(α-glycosyl) trichloroacetimidates, good yields of the inversion products, that is, the β-glycosides, are obtained. This novel conceptual approach to glycosidation revealed that for retention of configuration in addition a catalytic nucleophile is required that enables formation of the α-glucoside from the α-trichloroacetimidate. Preliminary studies with a catalyst possessing this 5-fold function, that is, adduct formation with the acceptor, hydrogen-bonding between the reactants, acid and base catalysis, and a catalytic nucleophile as part of a chiral framework supporting facial selection, exhibited good chances for final success in this endeavor. | {
"pile_set_name": "PubMed Abstracts"
} |
Stimulation of microsomal spironolactone metabolism by reduced glutathione.
The first step in the conversion of spironolactone (SP) to its biologically active metabolites is deacetylation to 7 alpha-thiospirolactone (7 alpha-thio-SL). Studies were done to evaluate the effects of reduced glutathione (GSH) on SP deacetylation by adrenal microsomal preparations. In the absence of GSH, adrenal microsomes catalyzed the conversion of SP to 7 alpha-thio-SL at low rates. Addition of GSH to the incubation medium caused a concentration-dependent stimulation of SP deacetylation. At a concentration of 10 mM, GSH caused a 4- to 5-fold increase in the rate of 7 alpha-thio-SL production. The results suggest that GSH may have an important role in the overall disposition of SP, including the formation of active metabolites. | {
"pile_set_name": "PubMed Abstracts"
} |
Cloning and characterization of Thermotoga maritima beta-glucuronidase.
The putative beta-glucuronidase from Thermotoga maritima, comprising 563 amino acid residues conjugated with a Hisx6 tag, was cloned and expressed in Escherichia coli. The enzyme has a moderately broad specificity, hydrolysing a range of p-nitrophenyl glycoside substrates, but has greatest activity on p-nitrophenyl beta-D-glucosiduronic acid (kcat=68 s(-1), kcat/K(M)= 4.5x10(5) M(-1) s(-1)). The enzyme also shows a relatively broad pH-dependence with activity from pH4.5 to 7.5 and a maximum at pH6.5. As expected the enzyme is stable towards heat denaturation, with a half life of 3h at 85 degrees C, in contrast to the mesophilic E. coli enzyme, which has a half life of 2.6h at 50 degrees C. The identity of the catalytic nucleophile was confirmed as Glu476 within the sequence VTEFGAD by trapping the glycosyl-enzyme intermediate using the mechanism-based inactivator, 2-deoxy-2-fluoro-beta-D-glucosyluronic acid fluoride and identifying the labeled peptide in peptic digests by HPLC-MS/MS methodologies. Consistent with this, the Glu476Ala mutant was shown to be hydrolytically inactive. The acid/base catalyst was confirmed as Glu383 by generation and kinetic analysis of enzyme mutants modified at that position, Glu383Ala and Glu383Gln. The demonstration of activity rescue by azide is consistent with the proposed role for this residue. This enzyme therefore appears suitable for use in enzymatic oligosaccharide synthesis in either the transglycosylation mode or by use of glycosynthase and thioglycoligase approaches. | {
"pile_set_name": "PubMed Abstracts"
} |
Olestra, a nondigestible, nonabsorbable fat. Effects on gastrointestinal and colonic transit.
Olestra, the name proposed for the mixture of hexa-, hepta- and octaesters of sucrose and long-chain fatty acids, is a nondigestible, nonabsorbable lipid with physical properties and taste that are similar to those of natural triglycerides. Our aim was to determine whether substitution with up to 30 g of olestra in a 45-g fat meal would alter gastric, small bowel, and colonic transit. Five groups, each of six healthy volunteers, ingested 800-kcal, 22-g protein meals containing a total of 45 g of lipid (N = 24) or 15 g of lipid (N = 6). Among those receiving the 45-g fat meal, 0, 7.5, 15 and 30 g of lipid were substituted with olestra (N = 6 per group). The 15-g fat meal consisted entirely of natural triglyceride. A dual gamma camera scintigraphic method was used to estimate gastric and small bowel transit (99mTc pellets in the meal) and colonic transit (111In pellets). The latter was achieved by the delayed release of 111In pellets from a capsule coated with a pH-sensitive polymer, methacrylate, that disintegrated in the terminal ileum. There were no differences in the gastric, small bowel, or colonic transits of any of the five equicaloric meals. Some individuals had a significantly greater 48-hr stool weight after ingesting 15 g of olestra, but stool weights of subjects consuming 7.5 g or 30 g of olestra did not differ from controls. We conclude that substitution with olestra of up to 30 g in a 45-g fat meal does not significantly alter gastrointestinal transit in healthy subjects. | {
"pile_set_name": "PubMed Abstracts"
} |
[Patterns of breast feeding and study of interfering factors in a primary health care facility].
The present study aims to evaluate the patterns of breast-feeding in a population of children depending on a Primary Attention Team. Its duration and any factors which may interfere with it were also studied. The breast-feeding period of 114 boys and 119 girls is reviewed. We found the following data: 85.2% of the mothers started to breast-feed their children. By the third month, 42.1% of them persisted with exclusive breast-feeding, whereas only 5.6% reached the sixth month. Commercial formulas were introduced as a result of health reasons in only 43.3% of the cases. The time of exclusive breast-feeding was significantly shorter (p < 0.05) in the children who required hospitalization during the breast-feeding, in the cases of mothers that smoke, when commercial formula was introduced at the mother's will and in those children who had a smaller weight at their birth and a smaller gestational age. After introduction of commercial formulas we observed a statistically significant increase in weight (p < 0.05). Nevertheless, the standard score of weight at six months of age, compared with that previous to the introduction of lacteal supplements, did not differ significantly. | {
"pile_set_name": "PubMed Abstracts"
} |
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