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Continuous Transcatheter Arterial Thrombolysis for Early Hepatic Artery Thrombosis After Liver Transplantation
Early hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss and patient death. The most effective treatment approach is still controversial. The purpose of this study was to assess the effect of continuous transcatheter arterial thrombolysis in the treatment of early HAT. Routine posttransplant color Doppler imaging (CDI) was performed to monitor hepatic artery
J. Zhou; J. Fan; J.-H. Wang; Z.-Q. Wu; S.-J. Qiu; Y.-H. Shen; Y.-H. Shi; X.-W. Huang; Z. Wang; Z.-Y. Tang; Y.-Q. Wang
Enhancing the Early Student Experience
ERIC Educational Resources Information Center
This paper is concerned with identifying how the early student experience can be enhanced in order to improve levels of student retention and achievement. The early student experience is the focus of this project as the literature has consistently declared the first year to be the most critical in shaping persistence decisions. Programme managers…
Trotter, Eileen; Roberts, Carole A.
Early enhancement of the inferior vena cava on helical CT.
Arteriovenous fistulas (AVFs) are abnormal communications between the arterial and the venous systems. We describe two cases in which an aortocaval fistula (ACF) and a deep femoral AVF were diagnosed on dynamic computer tomography (CT) by early transient enhancement of the inferior vena cava (IVC). Awareness of the specific CT features found in central and peripheral AVFs and the effects on the arterial and venous systems may enable the radiologist to make the diagnosis. PMID:12823918
Cura, Marco; Cura, Alejandro; Bugnone, Alejandro
Arterial Switch Operation in Patients with Intramural Coronary Artery: Early and Mid-term Results
Background The intramural coronary artery has been known as a risk factor for early death after an arterial switch operation (ASO). We reviewed the morphological characteristics and evaluated the early and mid-term results of ASO for patients with an intramural coronary artery. Materials and Methods From March 1994 to September 15th 2010, 158 patients underwent ASO at Dong-A and Pusan National University Hospitals for repair of transposition of the great arteries and double outlet right ventricle. Among these patients, 14 patients (8.9%) had an intramural coronary artery. Mean age at operation was 13.4±10.2 days (4 to 39 days) and mean body weight was 3.48±0.33 kg (2.88 to 3.88 kg). All patients except one were male. Eight patients had TGA/IVS and 4 patients had an aortic arch anomaly. Two patients (14.3%) had side-by-side great artery relation, of whom one had an intramural right coronary artery and the other had an intramural left anterior descending coronary artery. Twelve patients had anterior-posterior relation, all of whom had an intramural left coronary artery (LCA). The aortocoronary flap technique was used in coronary transfer in 8 patients, of whom one patient required a switch to the individual coronary button technique 2 days after operation because of myocardial ischemia. An individual coronary button implantation technique was adopted in 6, of whom 2 patients required left subclavian artery free graft to LCA during the same operation due to LCA injury during coronary button mobilization and LCA torsion. Results There was 1 operative death (7.1%), which occurred in the first patient in our series. This patient underwent an aortocoronary flap procedure for coronary transfer combining aortic arch repair. Overall operative mortality for 144 patients without an intramural coronary artery was 13.2% (19/144). There was no statistical difference in operative mortality between the patients with and without an intramural coronary artery (p>0.1). There was no late death. The mean follow-up duration was 52.1±43.0 months (0.5 to 132 months). One patient who had a subclavian artery free graft required LCA stenting 6.5 years after surgery for LCA anastomotic site stenosis. No other surviving patient needed any intervention for coronary problems. All patients had normal ventricular function at latest echocardiography and were in NYHA class 1. Conclusion The arterial switch operation in Transposition of Great Arteries or Double Outlet Right Ventricle patients with intramural coronary can be performed with low mortality; however, there is a high incidence of intraoperative or postoperative coronary problems, which can be managed with conversion to the individual coronary button technique and a bypass procedure using a left subclavian free graft. Both aortocoronary flap and individual coronary button implantation techniques for coronary transfer have excellent mid-term results.
Kim, Hyungtae; Kim, Si-Ho; Chang, Yun Hee; Ahn, Hyo Yeong; Lee, Hyoung Doo
Microcalcifications in Early Intimal Lesions of Atherosclerotic Human Coronary Arteries
Although calcium (Ca) precipitation may play a pathogenic role in atherosclerosis, information on temporal patterns of microcalcifications in human coronary arteries, their relation to expression of calcification-regulating proteins, and colocalization with iron (Fe) and zinc (Zn) is scarce. Human coronary arteries were analyzed post mortem with a proton microprobe for element concentrations and stained (immuno)histochemically for morphological and calcification-regulating proteins. Microcalcifications were occasionally observed in preatheroma type I atherosclerotic intimal lesions. Their abundance increased in type II, III, and IV lesions. Moreover, their appearance preceded increased expression of calcification-regulating proteins, such as osteocalcin and bone morphogenetic protein-2. In contrast, their presence coincided with increased expression of uncarboxylated matrix Gla protein (MGP), whereas the content of carboxylated MGP was increased in type III and IV lesions, indicating delayed posttranslational conversion of biologically inactive into active MGP. Ca/phosphorus ratios of the microcalcifications varied from 1.6 to 3.0, including amorphous Ca phosphates. Approximately 75% of microcalcifications colocalized with the accumulation of Fe and Zn. We conclude that Ca microprecipitation occurs in the early stages of atherosclerosis, inferring a pathogenic role in the sequel of events, resulting in overt atherosclerotic lesions. Microcalcifications may be caused by local events triggering the precipitation of Ca rather than by increased expression of calcification-regulating proteins. The high degree of colocalization with Fe and Zn suggests a mutual relationship between these trace elements and early deposition of Ca salts.
Roijers, Ruben B.; Debernardi, Nicola; Cleutjens, Jack P.M.; Schurgers, Leon J.; Mutsaers, Peter H.A.; van der Vusse, Ger J.
Early Arterial Differentiation and Patterning in the Avian Embryo Model
Of the many models to study vascular biology the avian embryo remains an informative and powerful model system that has provided important insights into endothelial cell recruitment, assembly and remodeling during development of the circulatory system. This review highlights several discoveries in the avian system that show how arterial patterning is regulated using the model of dorsal aortae development along the embryo midline during gastrulation and neurulation. These discoveries were made possible through spatially and temporally controlled gain-of-function experiments that provided direct evidence that BMP signaling plays a pivotal role in vascular recruitment, patterning and remodeling and that Notch-signaling recruits vascular precursor cells to the dorsal aortae. Importantly, BMP ligands are broadly expressed throughout embryos but BMP signaling activation region is spatially defined by precisely regulated expression of BMP antagonists. These discoveries provide insight into how signaling, both positive and negative, regulate vascular patterning. This review also illustrates similarities of early arterial patterning along the embryonic midline in amniotes both avian and mammalians including human, evolutionarily specialized from non-amniotes such as fish and frog.
Garriock, Robert J; Mikawa, Takashi
Evolution of risk factors influencing early mortality of the arterial switch operation
OBJECTIVESThe present study was undertaken to determine the independent risk factors for early mortality in the current era after arterial switch operation (ASO).BACKGROUNDPrior reports on factors affecting outcome of the ASO demonstrated that abnormal coronary arterial patterns were associated with increased risk of early mortality. As diagnostic, surgical and perioperative management techniques continue to evolve, the risk factors for the
Elizabeth D. Blume; Karen Altmann; John E. Mayer; Steven D. Colan; Kimberlee Gauvreau; Tal Geva
Liposomal nanoparticles encapsulating iloprost exhibit enhanced vasodilation in pulmonary arteries
Prostacyclin analogues are standard therapeutic options for vasoconstrictive diseases, including pulmonary hypertension and Raynaud's phenomenon. Although effective, these treatment strategies are expensive and have several side effects. To improve drug efficiency, we tested liposomal nanoparticles as carrier systems. In this study, we synthesized liposomal nanoparticles tailored for the prostacyclin analogue iloprost and evaluated their pharmacologic efficacy on mouse intrapulmonary arteries, using a wire myograph. The use of cationic lipids, stearylamine, or 1,2-di-(9Z-octadecenoyl)-3-trimethylammonium-propane (DOTAP) in liposomes promoted iloprost encapsulation to at least 50%. The addition of cholesterol modestly reduced iloprost encapsulation. The liposomal nanoparticle formulations were tested for toxicity and pharmacologic efficacy in vivo and ex vivo, respectively. The liposomes did not affect the viability of human pulmonary artery smooth muscle cells. Compared with an equivalent concentration of free iloprost, four out of the six polymer-coated liposomal formulations exhibited significantly enhanced vasodilation of mouse pulmonary arteries. Iloprost that was encapsulated in liposomes containing the polymer polyethylene glycol exhibited concentration-dependent relaxation of arteries. Strikingly, half the concentration of iloprost in liposomes elicited similar pharmacologic efficacy as nonencapsulated iloprost. Cationic liposomes can encapsulate iloprost with high efficacy and can serve as potential iloprost carriers to improve its therapeutic efficacy.
Jain, Pritesh P; Leber, Regina; Nagaraj, Chandran; Leitinger, Gerd; Lehofer, Bernhard; Olschewski, Horst; Olschewski, Andrea; Prassl, Ruth; Marsh, Leigh M
CT Arterial Portography: Causes of Technical Failure and Variable Liver Enhancement
OBJECTIVE. We studied the causes of technical failure and enhancement variability encountered during CT arterial portography. MATERIALS AND METHODS. CT arterial portograms and digital artenograms were obtained via the superior mesenteric artery before partial liver resection in 43 patients with malignant tumors. These studies were reviewed for causes of technical failure and variable enhancement. RESULTS. Eleven (26%) of 43 procedures
Erik K. Paulson; Mark E. Baker; David J. Hilleren; William P. Jones; Mark H. Knelson; Scott N. NadeF; Richard A. Leder; William C. Meyers
[Early atrial gene regulation of obesity-related arterial hypertension].
High fat diet (HFD) induces both arterial hypertension and tachycardia in dogs. Changes in heart rate occur early and are in part due to a decrease in the parasympathetic drive to the heart secondary to down-regulation of atrial muscarinic M2 receptors (Pelat et al. Hypertension 1999; 340: 1066-72). These data suggest that HFD is able to modify genic expression at atrial level. Thus, the aim of this work was to perform a systematic study of the genic expression profile in dogs made obese and hypertensive by 9 weeks of HFD. Blood pressure and heart rate were measured by telemetry implanted 15 days before starting regimen in 6 HFD and in 6 control dogs. HFD was the normal canine diet administered to controls but mixed with 300 g of beef fat. At the end of the experience, animals were sacrified and right atria were collected. Gene regulation was assessed in pooled tissue samples from both groups using suppressive substractive hybridization and microarray analysis. Genes with induction or repression rates of at least 20% when compared to controls were sequenced. As previously reported HFD induced a significant increase in body weight, blood pressure and heart rate when compared to controls. The results of SSH experiments led to the identification of 32 genes which are differentially regulated in atria from HFD dogs. Most are genes encoding proteins which have been previously shown to be regulated during various cardiopathies (MMP9, Na/K-ATPase 3...). These changes indicate the existence of early remodeling processes of atrial myocardium secondary to HFD. Other group of genes encodes proteins with no role identified in heart up today (lec-3, ERK-3, TRIP1, nucleophosmin...) or which function remains totally unknown. This work confirms that HFD is associated with early changes in gene expression in atrium. These changes are unlikely to be related to ventricular hypertrophy which is observed only during long-term HFD. Further studies are necessary to demonstrate the role of these modifications in the pathophysiological mechanisms leading to the increase in heart rate in this model of obesity-related arterial hypertension. PMID:12365082
Philip-Couderc, P; Smih, F; Pelat, M; Verwaerde, P; Pathak, A; Buys, S; Montastruc, J L; Senard, J M; Rouet, P
Early hemodynamic effects of olprinone hydrochloride after coronary artery bypass grafting
Our purpose was to evaluate the hemodynamic effects of olprinone hydrochloride early after coronary artery bypass grafting\\u000a (CABG). Fifteen patients undergoing CABG were administered a constant infusion of 0.1 ?g\\/kg\\/min of olprinone and continued\\u000a for 4 hours. No bolus infusion of olprinone was administered before continuous infusion. Systolic systemic arterial pressure,\\u000a systolic pulmonary arterial pressure, systemic vascular resistance and pulmonary
Akira Marui; Takaaki Mochizuki; Norimasa Mitsui; Tadaaki Koyama; Mayumi Horibe
Coronary flow reserve early and late after minimally invasive coronary artery bypass grafting in patients with totally occluded left anterior descending coronary artery
Background: The impairment of flow reserve of the left anterior descending coronary artery in the early postoperative period in patients receiving a left internal thoracic artery graft has been related to the effects of cardiopulmonary bypass. Indeed, the late improvement in flow has been attributed to a late increase in left internal thoracic artery diameter. Methods: We evaluated 12 patients
Ruggero De Paulis; Fabrizio Tomai; Achille Gaspardone; Luisa Colagrande; Paolo Nardi; Anna Ghini; Francesco Versaci; Alfonso Penta de Peppo; Pier Agostino Gioffrč; Luigi Chiariello
Analysis of Turbulent flow in early stages of atherosclerosis of coronary artery
NASA Astrophysics Data System (ADS)
During the early stages of atherosclerotic heart disease, fatty material accumulates in the coronary artery resulting in development of streaks of plaque and creating high levels of turbulence, and with significantly modified flow parameters. Diagnostic measures performed during this early stage may not show any evidence of coronary artery disease, because the lumen of the coronary artery has not decreased in caliber. These streaks do not obstruct the flow of blood but alter the flow characteristics, even at this preclinical stage. This talk presents the preliminary results for the analysis of turbulent flow characteristics for a range of atherosclerotic plaque configurations in the left main coronary artery. For this purpose a CAD/medical imaging based direct-simulation (DNS) tool has been developed. The Navier-stokes equations are solved in the vertical vorticity-velocity formulation. The plaque is introduced using immersed body technique. The geometric acquisition of the artery geometry and plaque morphology is obtained using CAD based commercial software.
Bhaganagar, Kiran
Outcome after local intra-arterial fibrinolysis compared with the natural course of patients with a dense middle cerebral artery on early CT
Our purpose was to relate the outcome after local intra-arterial fibrinolysis (LIF) to the natural course in middle cerebral\\u000a artery (MCA) occlusion. We retrospectively studied 40 patients with a dense middle cerebral artery on early CT; 20 were treated\\u000a with LIF within 6 h of onset of symptoms, 20 received "conventional" stroke therapy. The dense middle cerebral artery, which\\u000a is
M. Bendszus; H. Urbach; F. Ries; L. Solymosi
Enhanced vasocontraction of rat tail arteries by toxoflavin.
1. It has been suggested that the toxic effect of toxoflavin (TXF) produced by Pseudomonas cocovenenas is mainly due to the impairment of electron transfer of the mitochondrial respiratory chain. However, the cardiovascular effect of TXF is unknown. In the present study, the effect of TXF on the isometric contraction of rat isolated tail artery strips and the underlying mechanisms were investigated. 2. The basal force of the tissues was not affected by the toxin. However, the application of TXF before or during KCl (60 mM) stimulation potentiated KCl-induced vasocontraction, specifically the tonic phase of the contraction. 3. When the vessel strips were precontracted with phenylephrine (Phe), TXF further enhanced the tonic contraction of the tissue. Pretreatment of tissues with TXF also potentiated subsequent vasocontraction induced by Phe. The vasocontractor effects of TXF and Phe, however, were not additive. 4. The vascular effect of TXF was not mediated by oxygen-derived free radicals since catalase and SOD did not affect TXF-enhanced vasocontraction. In contrast, the vasocontractor effect of TXF was dependent on extracellular Ca2+ and abolished by nifedipine (a Ca2+ antagonist). TXF also had no effect on caffeine- or U46619-induced vasocontraction. 5. It is suggested that TXF may potentially contract blood vessels via its effect on Ca2+ channels. This effect of TXF depends on the contractile status of the vascular tissues.
Wang, Z.; Ma, M.; Wang, R.
Early diagnosis of peripheral arterial disease can save limbs.
Prompt identification and management of patients with peripheral arterial disease can improve quality of life, save limbs and reduce cardiovascular events. The most common initial symptom is leg pain on exertion or intermittent claudication. More severe or critical limb ischaemia can present with pain at rest, ulceration, tissue loss and/or gangrene, In most patients the symptoms remain stable, but approximately 20% will develop limb threatening critical ischaemia. The incidence of peripheral arterial disease increases with age and up to 20% of people aged over 60 are affected to some degree. The incidence is also high in smokers, diabetes patients, and those with coronary disease. A focused history should identify the presence and severity of intermittent claudication and any critical limb ischaemia. Examination should concentrate on the palpation of lower limb arterial pulses and look for signs of critical ischaemia such as ulceration. The key primary care investigation in suspected peripheral arterial disease is measurement of the ankle brachial pressure index. Lifestyle interventions are a key component of management. NICE recommends that a supervised exercise programme is offered to all patients with intermittent claudication. Pharmacological therapy should always include an antiplatelet agent and statin. Vasoactive drugs such as naftidrofuryl oxalate should be considered for symptom control in intermittent claudication when exercise has not led to a satisfactory improvement and the patient prefers not to be referred for revascularisation. Patients with severe and inadequately controlled symptoms should be referred to secondary care with a view to further imaging to assess the appropriateness of revascularisation. PMID:23214272
Savill, Peter
Mathematical Difficulty: Does Early Intervention Enhance Mathematical Performance?
ERIC Educational Resources Information Center
The need to ask educators about their opinions on the subject to what extent early intervention methods enhance mathematical performance is long overdue. The purpose of this quantitative research is to examine the extent to which teachers agree that early intervention methods enhance the mathematical performance of students with mathematical…
Graham, Jennifer
Umbilical artery waveform analysis based on maximum, mean and mode velocity in early human pregnancy
The objective of this study was to identify the best method for reconstructing blood-flow velocities from the early human umbilical artery to determine the physiological changes in fetal blood-flow velocity and heart rate. Pulsed Doppler recordings from the umbilical artery with a duration of approximately 7 s were made at 10–20 weeks of gestation. For reconstruction of the blood-flow velocity
Nicolette T. C. Ursem; Hans J. F. Brinkman; Piet C. Struijk; Wim C. J. Hop; Mark H. Kempski; Bradley B. Keller; Juriy W. Wladimiroff
Pulmonary Arterial Hypertension: Use of Delayed Contrast-Enhanced Cardiovascular Magnetic Resonance in Risk Assessment
Background Pulmonary arterial hypertension is a severe and progressive disease. Its early diagnosis is the greatest clinical challenge. Objective To evaluate the presence and extension of the delayed myocardial contrast-enhanced cardiovascular magnetic resonance, as well as to verify if the percentage of the myocardial fibrosis mass is a severity predictor. Methods Cross-sectional study with 30 patients with pulmonary arterial hypertension of groups I and IV, subjected to clinical, functional and hemodynamic evaluation, and to cardiac magnetic resonance. Results The mean age of patients was 52 years old, with female predominance (77%). Among the patients, 53% had right ventricular failure at diagnosis, and 90% were in functional class II/III. The mean of the 6-minute walk test was 395m. In hemodynamic study with right catheterism, the mean average pulmonary arterial pressure was 53.3mmHg, of the cardiac index of 2.1L/ min.m2, and median right atrial pressure was 13.5 mmHg. Delayed myocardial contrast enhanced cardiovascular magnetic resonance was found in 28 patients. The mean fibrosis mass was 9.9 g and the median percentage of fibrosis mass was 6.17%. The presence of functional class IV, right ventricular failure at diagnosis, 6-minute walk test < 300 meters and right atrial pressure ? 15 mmHg, with cardiac index < 2.0 L/ min.m2, there was a relevant association with the increased percentage of myocardial fibrosis. Conclusion The percentage of the myocardial fibrosis mass indicates a non-invasive marker with promising perspectives in identifying patients with high risk factors for pulmonary hypertension.
Bessa, Luiz Gustavo Pignataro; Junqueira, Flavia Pegado; Bandeira, Marcelo Luiz da Silva; Garcia, Marcelo Iorio; Xavier, Sergio Salles; Lavall, Guilherme; Torres, Diego; Waetge, Daniel
Robotic computer-assisted telemanipulation enhances coronary artery bypass
Objectives: Totally endoscopic coronary artery bypass grafting depends greatly on perfecting the anastomosis. We tested a new computer-assisted telemanipulation robot (Intuitive Surgical Inc, Mountain View, Calif) in performing endoscopic coronary bypass. Methods: On-bench anastomoses of the porcine arterial graft to the left anterior descending coronary artery were performed with both direct visualization and conventional surgical instruments (group I), endoscopic 3-dimensional
Hani Shennib; Amr Bastawisy; Joan McLoughlin; Frederic Moll
Busulphan-Cyclophosphamide Cause Endothelial Injury, Remodeling of Resistance Arteries and Enhanced Expression of Endothelial Nitric Oxide Synthase
Stem cell transplantation (SCT) is a curative treatment for malignant and non malignant diseases. However, transplantation-related complications including cardiovascular disease deteriorate the clinical outcome and quality of life. We have investigated the acute effects of conditioning regimen on the pharmacology, physiology and structure of large elastic arteries and small resistance-sized arteries in a SCT mouse model. Mesenteric resistance arteries and aorta were dissected from Balb/c mice conditioned with busulphan (Bu) and cyclophosphamide (Cy). In vitro isometric force development and pharmacology, in combination with RT-PCR, Western blotting and electron microscopy were used to study vascular properties. Compared with controls, mesenteric resistance arteries from the Bu-Cy group had larger internal circumference, showed enhanced endothelium mediated relaxation and increased expression of endothelial nitric oxide synthase (eNOS). Bu-Cy treated animals had lower mean blood pressure and signs of endothelial injury. Aortas of treated animals had a higher reactivity to noradrenaline. We conclude that short-term consequences of Bu-Cy treatment divergently affect large and small arteries of the cardiovascular system. The increased noradrenaline reactivity of large elastic arteries was not associated with increased blood pressure at rest. Instead, Bu-Cy treatment lowered blood pressure via augmented microvascular endothelial dependent relaxation, increased expression of vascular eNOS and remodeling toward a larger lumen. The changes in the properties of resistance arteries can be associated with direct effects of the compounds on vascular wall or possibly indirectly induced via altered translational activity associated with the reduced hematocrit and shear stress. This study contributes to understanding the mechanisms that underlie the early effects of conditioning regimen on resistance arteries and may help in designing further investigations to understand the late effects on vascular system.
Al-Hashmi, Sulaiman; Boels, Piet J. M.; Zadjali, Fahad; Sadeghi, Behnam; Sallstrom, Johan; Hultenby, Kjell; Hassan, Zuzana; Arner, Anders; Hassan, Moustapha
Surface roughness detection of arteries via texture analysis of ultrasound images for early diagnosis of atherosclerosis.
There is a strong research interest in identifying the surface roughness of the carotid arterial inner wall via texture analysis for early diagnosis of atherosclerosis. The purpose of this study is to assess the efficacy of texture analysis methods for identifying arterial roughness in the early stage of atherosclerosis. Ultrasound images of common carotid arteries of 15 normal mice fed a normal diet and 28 apoE(-/-) mice fed a high-fat diet were recorded by a high-frequency ultrasound system (Vevo 2100, frequency: 40 MHz). Six different texture feature sets were extracted based on the following methods: first-order statistics, fractal dimension texture analysis, spatial gray level dependence matrix, gray level difference statistics, the neighborhood gray tone difference matrix, and the statistical feature matrix. Statistical analysis indicates that 11 of 19 texture features can be used to distinguish between normal and abnormal groups (p<0.05). When the 11 optimal features were used as inputs to a support vector machine classifier, we achieved over 89% accuracy, 87% sensitivity and 93% specificity. The accuracy, sensitivity and specificity for the k-nearest neighbor classifier were 73%, 75% and 70%, respectively. The results show that it is feasible to identify arterial surface roughness based on texture features extracted from ultrasound images of the carotid arterial wall. This method is shown to be useful for early detection and diagnosis of atherosclerosis. PMID:24146940
Niu, Lili; Qian, Ming; Yang, Wei; Meng, Long; Xiao, Yang; Wong, Kelvin K L; Abbott, Derek; Liu, Xin; Zheng, Hairong
Systemic Arterial Pressure at Maturity in Rats Following Chronic Hypoxia in Early Life
BackgroundThe effect of prolonged hypoxemia in early life on systemic arterial blood pressure at maturity was assessed in Sprague–Dawley rats.MethodsAnimals hypoxic in early life (12 males, 10 females) were raised in hypoxia (FiO2 = 0.12) for the first 10 days of life and subsequently raised in normoxia, along with age-matched controls (11 males, 9 females). At 2 months of age,
Bryan Ross; Matthew McIntosh; Demetra Rodaros; Terence E. Hébert; Charles V. Rohlicek
Parasympathetic activity correlates with early outcome in patients with large artery atherosclerotic stroke
To evaluate the associations between autonomic function and early stroke outcome in different subtypes of cerebral infarct, 24 patients with acute large artery atherosclerotic infarction (LAA), 26 patients with acute lacunar infarction (LAC), and 19 control subjects were prospectively recruited. Stroke outcome by the National Institute of Health Stroke Score (NIHSS) and heart rate variability (HRV) by power spectral analysis
Po-Lin Chen; Terry B. J. Kuo; Cheryl C. H. Yang
Dobutamine Stress Echocardiography Early After Heart Transplantation Predicts Development of Allograft Coronary Artery Disease and Outcome
Objectives. This study sought to determine the prognostic significance of serial dobutamine stress echocardiography (DSE) in new heart transplant recipients and to examine the relation between persistent wall motion abnormalities and the eventual development of coronary artery disease (CAD) as assessed by angiography.Background. Allograft CAD is a major cause of graft failure. However, clinical diagnosis of the early disease remains
Kwame O Akosah; Susan McDaniel; Josephine S Hanrahan; Pramod K Mohanty
Early results and follow-up of balloon angioplasty for branch pulmonary artery stenoses.
Two hundred eighteen balloon angioplasty procedures were performed in 135 patients with branch pulmonary artery stenoses from June 1984 to February 1989. Arteries were dilated in patients with tetralogy of Fallot (n = 49), tetralogy of Fallot/pulmonary atresia (n = 64), isolated peripheral pulmonary artery stenoses (n = 58) and "other" lesions (the majority had truncus arteriosus or single ventricle and surgically induced pulmonary artery stenoses (n = 47). Mean age at dilation was 6.6 +/- 6.3 years (range 1 month to 38.5 years). The mean diameter of the lesion increased from 3.8 +/- 1.7 to 5.5 +/- 2.1 mm with dilation (p = 0.001). The overall success rate was 58% (127 of 218 dilations), assessed by the following criteria: an increase greater than or equal to 50% of predilation diameter, an increase greater than 20% in flow to the affected lung or a decrease greater than 20% in systolic right ventricular to aortic pressure ratio. Success did not correlate with patient age. Mean balloon to artery ratio was higher in successful (4.2) than in failed (3.0) angioplasty procedures (p = 0.0001). There were four early deaths: two of the patients had pulmonary artery rupture with angioplasty performed less than 1 month after pulmonary artery surgery. An aneurysm occurred in 11 arteries and transient pulmonary edema in four patients. At angiography performed a mean of 10 months (range 1 to 54) after dilation, the mean diameter of 57 arteries was unchanged (5.5 versus 5.4 mm). However, 5 of 32 initially successfully dilated vessels had returned to predilation size as a result of restenosis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2138184
Rothman, A; Perry, S B; Keane, J F; Lock, J E
Serum Carotenoids Reduce Progression of Early Atherosclerosis in the Carotid Artery Wall among Eastern Finnish Men
Background Several previous epidemiologic studies have shown that high blood levels of carotenoids may be protective against early atherosclerosis, but results have been inconsistent. We assessed the association between atherosclerotic progression, measured by intima-media thickness of the common carotid artery wall, and serum levels of carotenoids. Methods We studied the effect of carotenoids on progression of early atherosclerosis in a population-based study. The association between concentrations of serum carotenoids, and intima-media thickness of the common carotid artery wall was explored in 840 middle-aged men (aged 46–65 years) from Eastern Finland. Ultrasonography of the common carotid arteries were performed at baseline and 7-year follow-up. Serum levels of carotenoids were analyzed at baseline. Changes in mean and maximum intima media thickness of carotid artery wall were related to baseline serum carotenoid levels in covariance analyses adjusted for covariates. Results In a covariance analysis with adjustment for age, ultrasound sonographer, maximum intima media thickness, examination year, body mass index, systolic blood pressure, smoking, physical activity, serum LDL cholesterol, family history of coronary heart disease, antihypertensive medication and serum high sensitivity C-reactive protein, 7-year change in maximum intima media thickness was inversely associated with lycopene (p?=?0.005), ?-carotene (p?=?0.002) and ?-carotene (p?=?0.019), respectively. Conclusions The present study shows that high serum concentrations of carotenoids may be protective against early atherosclerosis.
Karppi, Jouni; Kurl, Sudhir; Ronkainen, Kimmo; Kauhanen, Jussi; Laukkanen, Jari A.
Early diagnosis and treatment of a posttraumatic pseudoaneurysm/dissection of the innominate artery.
A 25-year-old male developed a traumatic intimo-medial dissection and saccular pseudoaneurysm at the origin of the innominate artery following a motorcycle accident. On physical examination there was no perceivable trauma to the chest. In addition, there were no clinical symptoms that suggested this serious injury. The patient was managed with successful stent-graft placement on an elective basis. Azarcon F , Ghaleb M . Early diagnosis and treatment of a posttraumatic pseudoaneurysm/dissection of the innominate artery. Prehosp Disaster Med. 2014;29(1):1-3 . PMID:24495347
Azarcon, Fernando; Ghaleb, Melhelm
Enhancement and segmentation for NMR images of blood flow in arteries
NASA Astrophysics Data System (ADS)
STRACT The widespread prevalence of atherosclerotic vascular disease has given rise to the need for a simple noninvasive imaging examination of the cardiovascular performance of patients. The potential of using Magnetic Resonance (MR) Imaging to quantify flow in vivo has for reaching possibilities for the future of preventive medicine. In this paper we address the problem of using MR velocity imaging to analyse the flow boundaries in human arteries which are of great importance to the early diagnosis ef occlusive diseases. A flow related enhancement process is introduced in this paper. It is designed to suppress the residuals and the noisy background of the MR velocity images caused by misregistration tissue movement and uneven magnetic field and provide great improvement in signal to noise ratio. From the enhanced image the main flow areas can be delineated by a thresholding process which defines the kernel of the flow. The boundaries of the kernel region are then dynamically guided by a defined flow boundary localization process to their final positions. The results of the application of this coarse to fine process show its robustness and effectiveness for the determination of the blood blow boundaries form very low quality MR velocity images.
Yang, Guang-Zhong; Burger, Peter
Cardiovascular magnetic resonance assessment of ventricular function and myocardial scarring before and early after repair of anomalous left coronary artery from the pulmonary artery
Background In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown. Methods 8 ALCAPA-patients (mean age 10.0?±?5.8 months) underwent CMR before and early after (mean 4.9?±?2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars. Results LV dilatation (mean LVEDVI 171?±?94 ml/m2) and dysfunction (mean LV-EF 22?±?10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68?±?42 ml/m2, p?=?0.02; mean LV-EF 58?±?19 %, p?0.001). Preoperative CMR revealed myocardial scarring in 2 of the 8 patients and did not predict postoperative course. At follow-up CMR, one LGE-positive patient showed delayed recovery of LV function while myocardial scarring was still present in both patients. In two patients new-onset transmural scarring was found, although functional recovery after operation was sufficient. One of them showed a stenosis of the left coronary artery and required resurgery. Conclusions Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined.
The Enhancing Secondary Prevention in Coronary Artery Disease trial
Background: Proven efficacious therapies are sometimes underused in patients with chronic cardiac conditions, resulting in suboptimal outcomes. We evaluated whether evidence summaries, which were either unsigned or signed by local opinion leaders, improved the quality of sec- ondary prevention care delivered by primary care phys - icians of patients with coronary artery disease. Methods: We performed a randomized trial, clustered
Finlay A. McAlister; Miriam Fradette; Sumit R. Majumdar; Randall Williams; Michelle Graham; James McMeekin; William A. Ghali; Merril L. Knudtson; Jeremy Grimshaw
Enhanced contractile responses of arteries from streptozotocin diabetic rats to sodium fluoride.
1. Previous studies from this laboratory have demonstrated that alpha 1-adrenoceptor-mediated increases in tension and phosphoinositide metabolism are enhanced in the aorta and mesenteric arteries from diabetic rats. The purpose of the present investigation was to determine whether contractile responses to sodium fluoride (NaF), which directly stimulates GTP-binding proteins (G-proteins), are also enhanced in diabetic arteries. 2. NaF (1-20 mM) in the presence of 10 microM aluminium chloride produced slowly developing, concentration-dependent contractions in mesenteric arteries from three month streptozotocin-diabetic (60 mg kg-1, i.v.) male Wistar rats and age-matched control rats. The maximum contractile response but not the sensitivity to NaF was significantly greater in mesenteric arteries from diabetic than from control rats, as was the response to noradrenaline (NA). Maximum contractile responses of aorta and caudal artery from diabetic rats to NaF were also significantly enhanced. 3. Removal of the endothelium and denervation with 6-hydroxydopamine did not significantly alter the maximum contractile response of mesenteric arteries from either control or diabetic rats to NaF. Similarly, NaF had no effect on cyclic AMP levels in aorta, and no difference in cyclic AMP levels, either basally or in the presence of NaF, was detected between control and diabetic rat aorta. 4. Contractile responses of mesenteric arteries from both control and diabetic rats to NaF were diminished in calcium-free Krebs solution, but the NaF response remained significantly elevated in mesenteric arteries from diabetic rats compared to control. 5. Ryanodine (30 microM) which depletes intracellular calcium stores, nifedipine (3 microM) which blocks dihydropyridine-sensitive calcium channels and calphostin C (0.5 microM) which selectively inhibits protein kinase C, all significantly inhibited maximum contractile responses of mesenteric arteries from control and diabetic rats to NaF. There were no significant differences between control and diabetic arteries in the relative magnitude of the inhibition produce by the three antagonist. 6. These data suggest that there may be increased activation of the same signalling processes that mediate NA-stimulated vasoconstriction, perhaps contraction-associated G-proteins or the effectors coupled to these G-proteins, in response to NaF in mesenteric arteries from diabetic rats. This may also be responsible for the enhanced contractile responses of these arteries to alpha 1-adrenoceptor stimulation. Images Figure 7
Weber, L. P.; Chow, W. L.; Abebe, W.; MacLeod, K. M.
Enhanced endoscopic detection of early colon cancer
NASA Astrophysics Data System (ADS)
Enhanced endoscopic detection of small flat adenomas is becoming increasingly important as they have a reported 14 percent incidence of dysplasia when compared with 5 percent incidence in polypod adenomas of the same size. These lesions even when invasive do not show up against the translucent surrounding mucosa making endoscopic detection difficult. Dye spraying with indigo carmine makes their morphology clear, with well-circumscribed borders. Dye spraying and magnifying endoscopes can be used to observe pit patterns on the surface of the bowel. Combining dye spraying and high-resolution video endoscopy demonstrates well the colorectal epithelial surface. Scanning immersion video endoscopy visualizes the epithelial surface of the colorectal mucosa by high-resolution endoscopy after filling the lumen with water. Endoscopic ultrasound can be used to see if the lesion is intramucosal or not and assess the depth of invasion if malignancy is presented. Laser induced fluorescence spectroscopy has the potential to detect colonic dysplasia in vivo. Combining such technologies with conventional colonoscopy can help in the surveillance of large areas of colonic mucosa for the presence of dysplasia. Guided biopsy can replace random biopsy based on information provided at the time of colonoscopic examination.
Balachandar, Gowra; Trowers, Eugene A.
Early and mid-term results of minimally invasive coronary artery bypass grafting
Introduction Minimally invasive coronary artery bypass grafting (MICABG) is a less invasive method of performing surgical revascularization. This technique coupled with use of off pump technique of surgical revascularization makes it truly less invasive. This method is highly effective even in high-risk patients. Results of this procedure are comparable to standard off pump technique and are better than percutaneous coronary intervention utilizing drug-eluting stent. We present an early and mid-term result of the use of this technique. Method We enrolled 33 patients for analysis operated between 2008 and 2012. Operation was performed utilizing off-pump technique of coronary artery bypass grafting through a minimal invasive incision. Left internal mammary artery graft was done for single vessel disease and radial artery was utilized for other grafts if required. Median follow up of 2.5 years (6 months–4 years) is available. Results Median age was 58.5 years (41–77) and all were male. Single vessel disease was present in 7, double vessel in 14 and triple vessel disease in 12 patients. All the patients had normal left ventricular size and function. There was no operative and 30-day mortality. Conversion to median sternotomy to complete the operation was done in 6.6% (2 out of 33 patients). One patient had acute myocardial infarction and there were no deaths during follow up. Conclusion MICABG is a safe and effective method of revascularization in low risk candidates for coronary artery bypass grafting.
Pande, Shantanu; Agarwal, Surendra K.; Gupta, Devendra; Mohanty, Satayapriya; Kapoor, Aditya; Tewari, Satyendra; Bansal, Anubhav; Ambesh, Sushil P.
Expression of Zinc Finger Immediate Early Genes in Rat Brain After Permanent Middle Cerebral Artery Occlusion
The prolonged expression of the leucine zipper fos\\/jun immediate early genes (IEG) has been correlated with neuronal death after cerebral ischemia. In this study, the expression of six zinc finger IEG was examined using in situ hybridization in adult rats after middle cerebral artery occlusion (MCAO) with the suture model. NGFI-A, NGFI-B, NGFI-C, egr-2, egr-3, and Nurr1 mRNA were all
Jari Honkaniemi; Bradley A. States; Philip R. Weinstein; Jose Espinoza; Frank R. Sharp
Combined chemical shift imaging with early dynamic serial gadolinium-enhanced MRI in the characterization of adrenal lesions.
OBJECTIVE. The purpose of this study was to retrospectively evaluate early dynamic serial gadolinium-enhanced and chemical-shift imaging (CSI) MRI to distinguish benign from malignant adrenal tumors. MATERIALS AND METHODS. Between July 2007 and December 2011, 205 patients with 239 adrenal lesions (177 adenomas, 54 metastases, 5 pheochromocytomas, and 3 adrenal cortical carcinomas) underwent early dynamic serial gadolinium-enhanced MRI and CSI. CSI was assessed qualitatively and by calculating the adrenal index, and enhancement patterns were evaluated qualitatively and quantitatively. Statistical analyses were performed. RESULTS. Most adenomas exhibited either an arterial blush or homogeneous enhancement, whereas most metastases showed early peripheral or heterogeneous enhancement. Visualization of higher enhancement on arterial and venous phases enabled differentiation of adenomas from metastases in most cases. Moderate to high signal intensity drop on CSI was seen in 95.4% of adenomas and 14.8% of metastases. In lesions with this level of signal intensity drop, 87 of 88 lesions with a capillary blush were adenomas. Early dynamic serial imaging alone was a significant (p < 0.0001) indicator of nonadenoma (area under the curve [AUC], 0.912) with optimal sensitivity of 81% and specificity of 93% for differentiating adenomas from nonadenomas. Combined analysis (CSI and early dynamic serial imaging) was also significant (p < 0.0001 and p=0.0014, respectively) for diagnosing nonadenomas (AUC, 0.983) with optimal sensitivity of 94% and specificity of 98%. CONCLUSION. Early dynamic serial gadolinium-enhanced MRI aids in characterization of adrenal tumors, especially lesions that are categorized as indeterminate on the basis of CSI. PMID:24951201
Rodacki, Karina; Ramalho, Miguel; Dale, Brian M; Battisti, Sofia; de Campos, Rafael O P; Giardino, Antonello; Semelka, Richard C
Persistent renal enhancement after intra-arterial versus intravenous iodixanol administration
Purpose To examine the clinical significance of persistent renal enhancement after iodixanol administration. Methods We retrospectively studied 166 consecutive patients who underwent non-enhanced abdominopelvic CT within 7 days after receiving intra-arterial (n=99) or intravenous (n=67) iodixanol. Renal attenuation was measured for each non-enhanced CT scan. Persistent renal enhancement was defined as CT attenuation > 55 Hounsfield units (HU). Contrast-induced nephropathy (CIN) was defined as a rise in serum creatinine ? 0.5mg/dL within 5 days after contrast administration. Results While the intensity and frequency of persistent renal enhancement was higher after intra-arterial (mean CT attenuation of 73.7HU, seen in 54 of 99 patients, or 55%) than intravenous contrast material administration (51.8HU, seen in 21 of 67, or 31% p < 0.005), a multivariate regression model showed that the independent predictors of persistent renal enhancement were a shorter time interval until the subsequent non-enhanced CT (p<0.001); higher contrast dose (p<0.001); higher baseline serum creatinine (p<0.01); and older age (p<0.05). The route of contrast administration was not a predictor of persistent renal enhancement in this model. Contrast-induced nephropathy was noted in 9 patients who received intra-arterial (9%) versus 3 who received intravenous iodixanol (4%), and was more common in patients with persistent renal enhancement (p<0.01). Conclusion Persistent renal enhancement at follow-up non-contrast CT suggests a greater risk for contrast-induced nephropathy, but the increased frequency of striking renal enhancement in patients who received intra-arterial rather than intravenous contrast material also reflects the larger doses of contrast and shorter time to subsequent follow-up CT scanning for such patients.
Chou, Shinn-Huey; Wang, Zhen J.; Kuo, Jonathan; Cabarrus, Miguel; Fu, Yanjun; Aslam, Rizwan; Yee, Judy; Zimmet, Jeffrey M; Shunk, Kendrick; Elicker, Brett; Yeh, Benjamin M.
Endovascular exclusion of popliteal artery aneurysms with expanded polytetrafluoroethylene stent-grafts: early results.
There is increasing interest in using endovascular methods instead of surgical reconstruction to treat popliteal artery aneurysms. Exclusive use of the Viabahn stent-graft, a nitinol stent covered with expanded polytetrafluoroethylene, was assessed in the treatment of patients who presented with popliteal artery aneurysms in the absence of acute limb ischemia. Technical success, endoleaks, graft patency, freedom from amputation, and aneurysm sac flow and size changes were assessed by duplex ultrasound. From June 2004 to March 2006, 16 men (mean age, 76 years; range, 65-83) underwent endovascular exclusion of 23 popliteal artery aneurysms (mean diameter, 2.5 cm; range, 1.3-6.7 cm). Nine lesions had partial thrombus on preprocedural duplex imaging. Nineteen of the 23 limbs treated had at least 2-vessel tibial artery runoff. Procedures were performed under local anesthesia using ipsilateral percutaneous antegrade arterial access. All patients received 75 mg/day of clopidogrel afterward. Follow-up assessments included direct clinical examinations and duplex ultrasonography performed 1, 3, 6, and 12 months after the procedure. Primary patency and amputation-free survival were calculated using Kaplan-Meier analysis. Complete aneurysm exclusion (technical success) was achieved in all cases. During the mean follow-up of 7 months (range, 1-21 months), 22 of 23 treated limbs remained asymptomatic. One stent-graft thrombosis occurred 6 months after the procedure and was successfully treated with percutaneous mechanical thrombectomy, balloon angioplasty of a stent-graft stenosis, and insertion of an uncovered nitinol stent. No popliteal artery aneurysm sac size enlargements or endoleaks were detected. At 12 months, the treated limb mean ankle-brachial index was 1.0 (range, 0.82-1.31) and the primary and secondary patency rates were 93% and 100%, respectively. Early results with Viabahn endovascular stent-graft exclusion of asymptomatic popliteal artery aneurysms are promising. Patient selection for endovascular repair depends on suitable popliteal artery anatomy, extent of aneurysmal degeneration, and quality of tibial arterial runoff. PMID:17202092
Rajasinghe, Hiranya A; Tzilinis, Argyrios; Keller, Theresa; Schafer, Jeff; Urrea, Sandra
Duration of breast feeding and arterial distensibility in early adult life: population based study
Objectives To test the hypothesis that duration of breast feeding is related to changes in vascular function relevant to the development of cardiovascular disease. Design Population based observational study. Setting Cambridge. Participants 331 adults (171 women, 160 men) aged between 20 and 28 years, born in Cambridge Maternity Hospital. Main outcome measures Distensibility of brachial artery, type and duration of infant feeding, current lipid profile, and other cardiovascular risk factors. Results The longer the period of breast feeding the less distensible the artery wall in early adult life, with no sex differences (regression coefficient = ?3.93 ?m/month, 95% confidence interval ?7.29 to ?0.57, P=0.02). However, in those breast fed for less than four months, arterial distensibility was not significantly reduced compared with an exclusively formula fed group. The vascular changes observed were not explained by alterations in plasma cholesterol concentration in adult life. Conclusions Breast feeding in infancy is related to reduced arterial function 20 years later. These data should not alter current recommendations in favour of breast feeding, which has several benefits for infant health. Further work is needed, however, to explore the optimal duration of breast feeding in relation to cardiovascular outcomes.
Leeson, C P M; Kattenhorn, M; Deanfield, J E; Lucas, A
Impact of admission triglyceride for early outcome in diabetic patients with stable coronary artery disease
Background The role of triglyceride (TG) in predicting the outcomes in diabetic patients with coronary artery disease (CAD) has not been well investigated. Methods A total of 329 cases with stable angina pectoris (SAP) were prospectively enrolled and followed up for an average of 12 months. They were classified into the two groups according to the cut-off values of predicting early outcome of fasting TG level (low group <1.2 mmol/L, n?=?103; High group ?1.2 mmol/L, n?=?226). The relationship between the TG levels and early outcomes were evaluated. Results High TG group showed severer lipid profile and elevated inflammatory markers. During an average of 12-month follow-up, 47 out of 329 patients suffered from pre-specified outcomes. Area under the receivers operating characteristic curve suggested that TG, similar to serum Hemoglobin A1C (HbA1C), was a significant predictor of early outcome for diabetic patients with SAP (P?=?0.002). In Cox regression models, after adjusted age, gender, body mass index, other lipid parameters, fasting blood glucose, high sensitivity C-reactive protein, neutrophil count and HbA1C, TG remained as an independent predictor of adverse prognosis. Conclusions High level of fasting TG (?1.2 mmol/L) was an independent predictor for early outcome of diabetic patients with SAP as like as HBA1c and number of affected coronary arteries in the era of revascularization and statin therapeutics.
The Enhancing Secondary Prevention in Coronary Artery Disease trial
Background Proven efficacious therapies are sometimes underused in patients with chronic cardiac conditions, resulting in suboptimal outcomes. We evaluated whether evidence summaries, which were either unsigned or signed by local opinion leaders, improved the quality of secondary prevention care delivered by primary care physicians of patients with coronary artery disease. Methods We performed a randomized trial, clustered at the level of the primary care physician, with 3 study arms: control, unsigned statements or opinion leader statements. The statements were faxed to primary care physicians of adults with coronary artery disease at the time of elective cardiac catheterization. The primary outcome was improvement in statin management (initiation or dose increase) 6 months after catheterization. Results We enrolled 480 adults from 252 practices. Although statin use was high at baseline (n = 316 [66%]), most patients were taking a low dose (mean 32% of the guideline-recommended dose), and their low-density lipoprotein (LDL) cholesterol levels were elevated (mean 3.09 mmol/L). Six months after catheterization, statin management had improved in 79 of 157 patients (50%) in the control arm, 85 of 158 (54%) patients in the unsigned statement group (adjusted odds ratio [OR] 1.18, 95% CI 0.71–1.94, p = 0.52) and 99 of 165 (60%) patients in the opinion leader statement group (adjusted OR 1.51, 95% CI 0.94–2.42, p = 0.09). The mean fasting LDL cholesterol levels after 6 months were similar in all 3 study arms: 2.35 (standard deviation [SD] 0.86) mmol/L in the control arm compared with 2.24 (SD 0.73) among those in the opinion leader group (p = 0.48) and 2.19 (SD 0.68) in the unsigned statement group (p = 0.32). Interpretation Faxed evidence reminders for primary care physicians, even when endorsed by local opinion leaders, were insufficient to optimize the quality of care for adults with coronary artery disease. ClinicalTrials.gov trial register no. NCT00175240.
McAlister, Finlay A.; Fradette, Miriam; Majumdar, Sumit R.; Williams, Randall; Graham, Michelle; McMeekin, James; Ghali, William A.; Tsuyuki, Ross T.; Knudtson, Merril L.; Grimshaw, Jeremy
Time Resolved Contrast-Enhanced MR Projection Imaging of the Coronary Arteries with Intravenous Contrast Injection.
National Technical Information Service (NTIS)
In a method and apparatus for contrast-enhanced magnetic resonance (MR) angiography of the right coronary artery of a patient, a bolus of MR contrast agent is selected to have a size that will cause the bolus, after injection into the patient, to wash out...
D. Li J. D. Green
Safety of Early Carotid Artery Stenting after Systemic Thrombolysis: A Single Center Experience
Background. Patients with acute ischemic stroke due to internal carotid artery (ICA) disease are at high risk of early stroke recurrence. A combination of IV thrombolysis and early carotid artery stenting (CAS) may result in more effective secondary stroke prevention. Objective. We tested safety and durability of early CAS following IV thrombolysis in stroke patients with residual stenosis in the symptomatic ICA. Methods. Of consecutive patients treated with IV rtPA, those with residual ICA stenosis ?70% or <70% with an ulcerated plaque underwent early CAS (>24 hours). The protocol included pre-rtPA MRI and MR angiography, and post-rtPA carotid ultrasound and CT angiography. Stroke severity was assessed by the NIH Stroke Scale (NIHSS). Three- and twelve-month stent patency was assessed by ultrasound. Twelve-month functional outcome was assessed by the modified Rankin Scale (mRS). Results. Of 145 consecutive IV rtPA-treated patients, 6 (4%) underwent early CAS. Median age was 76 (range 67–78) years, median NIHSS at stroke onset was 12 (range 9–16) and 7 (range 7-8) before CAS. Median onset-to-CAS time was 48 (range 30–94) hours. A single self-expandable stent was implanted to cover the entire lesion in all patients. The procedure was uneventful in all patients. After 12 months, all patients had stent patency, and the functional outcome was favourable (mRS ? 2) in all but 1 patient experiencing a recurrent stroke for new-onset atrial fibrillation. Conclusion. This small case series of a single centre suggests that early CAS may be considered a safe alternative to CEA after IV rtPA administration in selected patients at high risk of stroke recurrence.
Sallustio, Fabrizio; Koch, Giacomo; Rocco, Alessandro; Rossi, Costanza; Pampana, Enrico; Gandini, Roberto; Meschini, Alessandro; Diomedi, Marina; Stanzione, Paolo; Di Legge, Silvia
Enhanced vasoconstrictor responses in renal and femoral arteries of the golden hamster during hibernation
The present study assessed local regulation of vascular tone of euthermic (control), cold control and hibernating golden hamsters. Sympathetic neurotransmission in the renal artery, the long term effects of hibernation on perivascular nerve activity, and the responsiveness of femoral artery to a number of neurotransmitters and hormones with both constrictor and dilator actions during hibernation are described.The contractile responses of the renal arterial rings to transmural nerve stimulation (80 V, 0.1 ms, 4–64 Hz, for 1 s) were negligible in controls, significantly increased at higher frequencies of stimulation in cold controls and markedly enhanced in the hibernating group at all frequencies tested. The contractile responses to exogenous noradrenaline (NA; 0.1–100 ?m) were significantly increased in the renal arteries of hibernating hamsters compared with controls, but not compared with cold controls. Responses to exogenous ATP (1–3000 ?m) and KCl (120 mm) were similar among all experimental groups.The maximal contractile responses of femoral arterial rings to the sympathetic co-transmitter ATP and 5-hydroxytryptamine were increased by approximately 124 % and 99 %, respectively, in hibernating compared with cold control preparations without a change in the concentration of agonist that produces half-maximal response. However, the responses to NA were not altered during hibernation.Vasoconstriction of femoral arterial rings in response to arginine vasopressin was significantly enhanced in both cold controls and hibernating groups, while vasoconstriction in response to endothelin-1 and KCl was unaltered.The dilator responses of femoral arterial rings to acetylcholine, sodium nitroprusside and adenosine were not different among the groups.It is suggested that the marked augmentation of sympathetic neurotransmission, selective supersensitivity of the vascular smooth muscle to sympathetic contractile agents and unaltered vasodilatory mechanisms may provide a means for maintenance of vascular tone and peripheral resistance during hibernation.
Karoon, Parastoo; Knight, Gillian; Burnstock, Geoffrey
Acute Treatment with Candesartan Reduces Early Injury After Permanent Middle Cerebral Artery Occlusion
We have shown that reduction of blood pressure (BP) immediately after the onset of reperfusion reduced neurovascular damage and improved functional outcome after experimental cerebral ischemia and candesartan is particularly effective in improving long-term functional outcome. In this study, we sought to determine if early BP lowering with candesartan, in the presence of an occluded cerebral artery, will reduce injury and improve outcome after experimental stroke. Male Wistar rats underwent 24 h or 7 days of middle cerebral artery occlusion (MCAO). A single dose of 1 mg/kg candesartan was administered intravenously at 3 h after MCAO. Animals received neurobehavioral testing at 3 h, 24 h, and 7 days, and blood pressure was measured by telemetry. Animals had brain tissue collected for infarct size (24 h and 7 days), hemoglobin content, matrix metalloproteinase (MMP) activity, and vascular endothelial growth factor (VEGF) expression (24 h only). Candesartan significantly decreased blood pressure, infarct size (?20%; p=0.021), hemoglobin excess (?50%; p=0.0013), and edema (?35%; p=0.0005) at 24 h after MCAO. This resulted in a reduced cerebral perfusion deficit (p=0.034) in the ischemic hemisphere compared with saline and significantly improved Bederson scores and paw grasp. MMP-2, MMP-9, and VEGF were significantly increased by MCAO, but there were no differences between candesartan- and saline-treated animals. There were no significant differences in behavioral outcome at day 7. BP lowering with candesartan reduces early brain injury after experimental stroke even when the artery remains occluded. The early benefits were not sustained at 7 days, as seen in reperfused animals, however. The neuroprotection and neurorestorative properties of candesartan may occur by separate distinct mechanisms.
Guan, Weihua; Kozak, Anna; El-Remessy, Azza B.; Johnson, Maribeth H.; Pillai, Bindu A.
A common variant on chromosome 9p21 affects the risk of early-onset coronary artery disease.
Background Two single nucleotide polymorphisms (SNPs, rs10757278 and rs2383207) on chromosome 9p21 have been proved to be associated with myocardial infarction. We investigated whether these two genetic markers are determinants of early-onset coronary artery disease. Methods and results A total of 444 consecutive patients were studied including 212 cases with coronary stenosis >or=50% or previous myocardial infarction and 232 controls without documented coronary artery disease. Ligase detection reaction was performed to detect two SNPs. After adjustment of clinical parameters, significant associations were identified for the rs2383207 and rs10757278 SNPs, with A/G and G/G genetypes at rs10757278 and G/G genetype carriers at rs2383207 having a higher risk of early-onset coronary artery disease than carriers of A/A genotype (odds ratio [OR] 2.207, 95% CI: 1.069-4.394, P = 0.028; OR 3.051, 95% CI: 1.086-8.567, P = 0.004; OR 2.964, 95% CI: 1.063-8.265, P = 0.038, respectively). There were no associations between rs10757278 and rs2383207 genotypes and the severity of coronary artery disease (both P > 0.05). Conclusions The rs10757278 and rs2383207 variants are determinants for early-onset coronary artery disease. These markers may help the identification of patients at increased risk for early-onset coronary artery disease. PMID:18459066
Chen, Zhong; Qian, Qi; Ma, Genshan; Wang, Jiahong; Zhang, Xiaoli; Feng, Yi; Shen, Chengxing; Yao, Yuyu
Early calcifications in human coronary arteries as determined with a proton microprobe.
The current paradigm reads that calcifications characterize the advanced and complex lesions in the atherosclerotic process. To explore the possibility that coronary artery wall calcifications already commence at an early stage of atherosclerosis, a combination of proton beam techniques with a (sub-) micrometer resolution, i.e., micro-proton induced X-ray emission, backward and forward scattering spectroscopy, was applied on human coronary arteries with lesions preceding overt atheromas. The detection limits of phosphorus and calcium in each separate pixel, 0.88*0.88 microm2 in size, were approximately 150 and 80 microg/g dry weight, respectively. Calcium distributions of entire coronary artery cross section were obtained, and calcifications were demonstrated at a preatheroma stage of the atherosclerotic process. The size of the microcalcifications varied between 1 and 10 microm. The composition of the microcalcifications was deduced from the calcium-to-phosphorus ratio. In order to quantify this ratio, the thickness of the specific X-ray absorber used for PIXE had to be accurately determined. Also, thick target PIXE calculations were performed and the method was validated. The calcium-to-phosphorus ratios of the microcalcifications were assessed with good accuracy and varied from 1.62 to 2.79, which corresponds with amorphous calcium phosphate. PMID:18027908
Roijers, Ruben B; Dutta, Raj K; Cleutjens, Jack P M; Mutsaers, Peter H A; de Goeij, Jeroen J M; van der Vusse, Ger J
Decreased carotid artery distensibility as a sign of early atherosclerosis in viscose rayon workers.
Carbon disulphide (CS(2)) is known to accelerate atherosclerosis and to increase the risk for cardiovascular diseases. To assess the effect of CS(2) on the functional (distensibility and compliance) and the structural (intima media thickness) properties of the common carotid artery, and blood pressure and lipid metabolism parameters, a cross-sectional study on 85 workers from a viscose rayon factory and 37 controls was carried out. Exposure to CS(2) was assessed by personal monitoring and was well below the threshold limit value-time weighted average. Carotid arterial wall properties were determined using a non-invasive ultrasound wall movement detector system. No significant effect of CS(2) on blood pressure, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol or triglycerides was found. Among the vascular parameters studied, only distensibility was significantly lower and heart rate was significantly higher in exposed subjects compared with the controls. In conclusion, occupational exposure to CS(2) may cause early alterations in arterial elastic properties in young individuals, and even before lipid and clinical findings have occurred, important functional changes in the vessel wall are present. PMID:11463867
Kotseva, K; Braeckman, L; Duprez, D; De Bacquer, D; De Buyzere, M; Van De Veire, N; Vanhoorne, M
Molecular Imaging Insights into Early Inflammatory Stages of Arterial and Aortic Valve Calcification
Traditional imaging modalities such as computed tomography, although perfectly adept at identifying and quantifying advanced calcification, cannot detect the early stages of this disorder and offer limited insight into the mechanisms of mineral dysregulation. This review presents optical molecular imaging as a promising tool that simultaneously detects pathobiological processes associated with inflammation and early stages of calcification in vivo at the (sub)cellular levels. Research into treatment of cardiovascular calcification is lacking, as shown by clinical trials that have failed to demonstrate the reduction of calcific aortic stenosis. Hence the need to elucidate the pathways that contribute to cardiovascular calcification and to develop new therapeutic strategies to prevent or reverse calcification has driven investigations into the use of molecular imaging. This review discusses studies that have used molecular imaging methods to advance knowledge of cardiovascular calcification, focusing in particular on the inflammation-dependent mechanisms of arterial and aortic valve calcification.
New, Sophie E. P.; Aikawa, Elena
Arterial Blood Pressure Management during Carotid Endarterectomy and Early Cognitive Dysfunction
Background A common practice during cross-clamp of carotid endarterectomy (CEA) is to manage mean arterial pressure (MAP) above baseline to optimize collateral cerebral blood flow and reduce risk of ischemic stroke. Objective To determine whether MAP management ?20% above baseline during cross-clamp is associated with lower risk of early cognitive dysfunction, a subtler form of neurologic injury than stroke. Methods One hundred eighty-three patients undergoing CEA were enrolled in this ad hoc study. All patients had radial arterial catheters placed prior to induction of general anesthesia. MAP was managed at the discretion of the anesthesiologist. All patients were evaluated with a battery of neuropsychometric tests pre-operatively and 24hrs post-operatively. Results Overall, 28.4% of CEA patients exhibited early cognitive dysfunction (eCD). Significantly fewer patients with MAP ?20% above baseline during cross-clamp exhibited eCD than those managed <20% above (11.6% vs. 38.6%, P<0.001). In a multivariate logistic regression model, MAP ?20% above baseline during the cross-clamp period was associated with significantly lower risk of eCD (OR: 0.18 [0.07–0.40], P<0.001), while diabetes mellitus (OR: 2.73 [1.14–6.61], P=0.03) and each additional year of education (OR: 1.19 [1.06–1.34], P=0.003) were associated with significantly higher risk of eCD. Conclusion The observations of this study suggest MAP management ?20% above baseline during cross-clamp of the carotid artery may be associated with lower risk of eCD after CEA. More prospective work is necessary to determine whether MAP ?20% above baseline during cross-clamp can improve the safety of this commonly performed procedure.
Heyer, Eric J.; Mergeche, Joanna L.; Anastasian, Zirka H.; Kim, Minjae; Mallon, Kaitlin A.; Connolly, E. Sander
Peripheral resistance artery blood flow in subjects with abnormal glucose tolerance is improved following enhanced external counterpulsation therapy.
Enhanced external counterpulsation (EECP) improves resistance artery function in coronary artery disease patients. However, whether EECP elicits similar effects in persons with abnormal glucose tolerance (AGT) is unknown. Here we provide novel evidence that EECP significantly improves resistance arterial function in the forearm of persons with AGT, whereas the calf only approached significance (P ? 0.10). These improvements were coincident with greater glycemic control, providing further insight into the potential mechanisms of EECP-mediated alterations in glycemia. PMID:24766247
Martin, Jeffrey S; Beck, Darren T; Braith, Randy W
Efficient sampling of early signal arrival for estimation of perfusion and transit time in whole-brain arterial spin labeling.
Arterial spin labeling can be used to measure both cerebral perfusion and arterial transit time. However, accurate estimation of these parameters requires adequate temporal sampling of the arterial spin labeling difference signal. In whole-brain multislice acquisitions, two factors reduce the accuracy of the parameter estimates: saturation of labeled blood in transit and inadequate sampling of early difference signal in superior slices. Label saturation arises when slices are acquired inferior-to-superior such that slice selection in proximal slices spoils the label for a distal slice. Inadequate sampling arises when the time spent acquiring inferior slices is too long to allow early sampling of the difference signal in superior slices. A novel approach to multislice imaging is proposed to address these two issues. In round-robin arterial spin labeling, slices are acquired in a different order after every pair of control-label acquisitions. Round-robin arterial spin labeling enables the acquisitions of all slices across the same range of postlabel delays in a descending superior-to-inferior order. This eliminates the temporal sampling problem and greatly reduces label saturation. Arterial transit time estimates obtained for the whole brain with round-robin arterial spin labeling show better agreement with a single-slice acquisition than do conventional multislice acquisitions. PMID:22189961
Lee, Wayne; Janik, Rafal; Scouten, Amy; Stefanovic, Bojana; Sled, John G
Parasympathetic activity correlates with early outcome in patients with large artery atherosclerotic stroke.
To evaluate the associations between autonomic function and early stroke outcome in different subtypes of cerebral infarct, 24 patients with acute large artery atherosclerotic infarction (LAA), 26 patients with acute lacunar infarction (LAC), and 19 control subjects were prospectively recruited. Stroke outcome by the National Institute of Health Stroke Score (NIHSS) and heart rate variability (HRV) by power spectral analysis were recorded. The LAA group had lower high-frequency power (HF, P=0.017), lower normalized HF (P=0.002), higher normalized low-frequency power (LF%, P=0.016), and higher ratio of LF to HF (P=0.003) than both the LAC and control groups. Multivariate regression analysis in the LAA group showed that HF significantly correlated with early outcome (standardized coefficient=-0.486, P=0.016), and HF less than 3.9 [ln(ms(2))] was an independent risk factor for NIHSS?4 at seventh day after admission (odd ratio=6.00, 95% confidence interval 1.02-35.37, P=0.048). There was no significant correlation between any HRV parameter and early stroke outcome in the LAC group. There were different autonomic function properties between LAA and LAC groups, and depressed parasympathetic modulation was associated with worse early outcome in patients with LAA. PMID:22118864
Chen, Po-Lin; Kuo, Terry B J; Yang, Cheryl C H
Contrast-enhanced sonography during uterine artery embolization for the treatment of leiomyomas.
Uterine artery embolization (UAE) is a successful and safe treatment for symptomatic leiomyomas. However, rare complications such as premature menopause and uterine necrosis can arise because of embolization of non-target tissues. We studied the feasibility of using contrast-enhanced sonography with intravenous SonoVue just before, during and after complete occlusion of both uterine arteries. In a patient with multiple, large, symptomatic leiomyomas, contrast-enhanced imaging established that the UAE was technically successful and that myometrial vascularity was not reduced. Our case suggests that ultrasound contrast agents may have a role in monitoring UAE and thus may help prevent ischemic complications. Further studies are required to confirm this. PMID:14971005
Marret, H; Tranquart, F; Sauget, S; Alonso, A M; Cottier, J-P; Herbreteau, D
Risk factors and therapeutic results of early local recurrence after transcatheter arterial chemoembolization
AIM: To identify factors affecting early local recurrence after transcatheter arterial chemoembolization (TACE) and investigate treatments and outcomes for local recurrence. METHODS: Early local recurrence and no early local recurrence groups drawn from 134 patients who were initially diagnosed with hepatocellular carcinoma (HCC) and showed a complete response (CR) to TACE treatment between January 1, 2006, and January 31, 2012, were analyzed by univariate and multivariate analyses. Additionally, the subsequent treatment for patients with recurrence was analyzed, and in cases in which TACE had been performed, the cumulative recurrence rates were calculated using the Kaplan-Meier method and compared with those of the primary lesion. RESULTS: The 1-, 2-, and 3-year survival rates were 92.3%, 60.2%, and 39.8%, respectively, in the early local recurrence group, which were significantly lower than those in both the late local and no local recurrence groups (P < 0.001). On multivariate analyses, non-compact lipiodol uptake, large tumor size, and an alpha-fetoprotein > 20 ng/mL after achieving a CR were significant predictors. When TACE was performed for early and late locally recurrent lesions, a CR was observed in 15 patients (41.7%) and 11 patients (78.6%), and the cumulative recurrence rates at 6, 12, and 24 mo were 17.9%, 43.3%, and 71.2%, respectively, which did not differ significantly from those after the first CR of 20.5%, 44.0%, and 58.6%, respectively (P = 0.639). CONCLUSION: Closer monitoring and active treatments must be provided to patients with risk factors for early local recurrence of HCC.
Rou, Woo Sun; Lee, Byung Seok; Moon, Hee Seok; Lee, Eaum Seok; Kim, Seok Hyun; Lee, Heon Young
Contrast-enhanced magnetic resonance angiography of mammary artery grafts after minimally invasive coronary bypass surgery
Background. The aim of the study was to investigate the application of the contrast-enhanced magnetic resonance angiography (CE-MRA) for the visualization of left internal mammary artery (LIMA) bypass.Methods. A total of 30 patients with LIMA bypass (22 men, 8 women, 35 to 77 years) received a CE-MRA 4 to 20 days after surgery. The non–ECG-triggered CE-MRA was performed during expiration
Herbert O Vetter; Rudolf Driever; Heinrich Mertens; Udo Kempkes; Bernhard M Cramer
DDAVP Enhances Platelet Adherence and Platelet Aggregate Growth on Human Artery Subendothelium
The effect of intravenous 1 -deamino (8-D-arginine)vaso- pressin (DDAVP) administration on platelet interaction with human artery subendothelium was investigated with flowing blood from five normal individuals and 1 2 patients with von Willebrand's disease (vWD). Three of the patients were diagnosed as vWD subtype I. four as subtype Ila. and five as subtype llb. DDAVP administration to normals enhanced platelet
Kjell S. Sakariassen; Marco Cattaneo; Zaverio M. Ruggeri; Piero M. Mannucci; Jan J. Sixma
Role of Lipoxygenase Metabolites of Arachidonic Acid in Enhanced Pulmonary Artery Contractions of Female Rabbits
Pulmonary arterial hypertension is characterized by elevated pulmonary artery pressure and vascular resistance. In women the incidence is 4 fold greater than that in men. Studies suggest sustained vasoconstriction is a factor in increased vascular resistance. Possible vasoconstrictor mediators include arachidonic acid-derived lipoxygenase metabolites. Our studies in rabbits showed enhanced endothelium-dependent contractions to arachidonic acid in pulmonary arteries from females compared to males. Because treatment with a non-specific lipoxygenase inhibitor reduced contractions in females but not males, the present study identified which lipoxygenase isoform contributes to sex-specific pulmonary artery vasoconstriction. 15- and 5- but not 12-lipoxygenase protein expression was greater in females. Basal and A23187-stimulated release of 15-, 5- and 12-hydroxyeicosatetraenoic acid from females and males was measured by liquid chromatography/mass spectrometry. Only 15-hydroxyeicosatetraenoic acid synthesis was greater in females compared to males under both basal and stimulated conditions. Vascular contractions to 15-hydroxyeicosatetraenoic acid were enhanced in females compared to males (maximal contraction; 44 ± 6% vs 25 ± 3%). The specific 15-lipoxygenase inhibitor PD146176 (12 ?mol/L) decreased arachidonic acid-induced contractions in females (maximal contraction; 93 ± 4% vs 57 ± 10%). If male pulmonary arteries were incubated with estrogen (1 ?mol/L, 18 hrs), protein expression of 15-lipoxygenase, and 15-hydroxyeicosatetraenoic acid production increased. Mechanisms to explain the increased incidence of pulmonary hypertension in women are not known. Results suggest the 15-lipoxygenase pathway is different between females and males and is regulated by estrogen. Understanding this novel sex-specific mechanism may provide insight into the increased incidence of pulmonary hypertension in females.
Pfister, Sandra L.
ULTRASOUND-ENHANCED rt-PA THROMBOLYSIS IN AN EX VIVO PORCINE CAROTID ARTERY MODEL
Ultrasound is known to enhance recombinant tissue plasminogen activator (rt-PA) thrombolysis. In this study, occlusive porcine whole blood clots were placed in flowing plasma within living porcine carotid arteries. Ultrasonically induced stable cavitation was investigated as an adjuvant to rt-PA thrombolysis. Aged, retracted clots were exposed to plasma alone, plasma containing rt-PA (7.1 ± 3.8 ?g/mL) or plasma with rt-PA and Definity® ultrasound contrast agent (0.79 ± 0.47 ?L/mL) with and without 120-kHz continuous wave ultrasound at a peak-to-peak pressure amplitude of 0.44 MPa. An insonation scheme was formulated to promote and maximize stable cavitation activity by incorporating ultrasound quiescent periods that allowed for the inflow of Definity®-rich plasma. Cavitation was measured with a passive acoustic detector throughout thrombolytic treatment. Thrombolytic efficacy was measured by comparing clot mass before and after treatment. Average mass loss for clots exposed to rt-PA and Definity® without ultrasound (n = 7) was 34%, and with ultrasound (n = 6) was 83%, which constituted a significant difference (p < 0.0001). Without Definity® there was no thrombolytic enhancement by ultrasound exposure alone at this pressure amplitude (n = 5, p < 0.0001). In the low-oxygen environment of the ischemic artery, significant loss of endothelium occurred but no correlation was observed between arterial tissue damage and treatment type. Acoustic stable cavitation nucleated by an infusion of Definity® enhances rt-PA thrombolysis without apparent treatment-related damage in this ex vivo porcine carotid artery model.
Hitchcock, Kathryn E.; Ivancevich, Nikolas M.; Haworth, Kevin J.; Caudell Stamper, Danielle N.; Vela, Deborah C.; Sutton, Jonathan T.; Pyne-Geithman, Gail J.; Holland, Christy K.
The early and mid-term results of carotid artery stenting in high-risk patients
Purpose This study aimed to investigate early and mid-term outcomes of carotid artery stenting (CAS). Methods We retrospectively reviewed 111 patients who were treated for carotid stenosis between October 2004 and December 2009 (42 CASs and 69 carotid endarterectomies [CEAs]). Results CAS group was older than CEA group (70 years vs. 67 years, P = 0.001). Coronary artery disease and high lesion above the 2nd cervical vertebral body were more common in CAS group (29% vs. 13%, P = 0.002; 4% vs. 24%, P = 0.004). The 30-days stroke rate was higher in CAS group (10% vs. 1% in CEA group, P = 0.067, Fisher's exact test). New brain lesions on diffusion-weighted magnetic resonance imaging were more common in CAS group (48% vs. 20% in CEA group, P = 0.002, chi-square test). The 1-, 3-year freedom from stroke were 91%, 84% in CAS group and 99%, 99% in CEA group (P = 0.007, log-rank test). Univariate analysis showed that female gender and age > 70 years were related with postprocedural neurological complications (P = 0.046 and P = 0.007, log-rank test). However, none were independent risk factors on multivariate analysis. Conclusion In our series, the rates of peri-procedural neurological complications in CAS group were significantly high. These results suggest that more experience and restricted patient selection will be needed for CAS.
Yun, Woo-Sung; Suh, Bo-Yang
The unrecognized epidemic of blunt carotid arterial injuries: early diagnosis improves neurologic outcome.
OBJECTIVE: To determine the benefit of screening for blunt carotid arterial injuries (BCI) in patients who are asymptomatic. SUMMARY BACKGROUND DATA: Blunt carotid arterial injuries have the potential for devastating complications. Published studies report 23% to 28% mortality rates, with 48% to 58% of survivors having permanent severe neurologic deficits. Most patients have neurologic deficits when the injury is diagnosed. The authors hypothesized that screening patients who are asymptomatic and instituting early therapy would improve neurologic outcome. METHODS: The Trauma Registry of the author's Level I Trauma Center identified patients with BCI from 1990 through 1997. Beginning in August 1996, the authors implemented a screening for BCI. Arteriography was used for diagnosis. Patients without specific contraindications were anticoagulated. Endovascular stents were deployed in the setting of pseudoaneurysms. RESULTS: Thirty-seven patients with BCI were identified among 15,331 blunt-trauma victims (0.24%). During the screening period, 25 patients were diagnosed with BCI among 2902 admissions (0.86%); 13 (52%) were asymptomatic. Overall, eight patients died, and seven of the survivors had permanent severe neurologic deficits. Excluding those dying of massive brain injury and patients admitted with coma and brain injury, mortality associated with BCI was 15%, with severe neurologic morbidity in 16% of survivors. The patients who were asymptomatic at diagnosis had a better neurologic outcome than those who were symptomatic. Symptomatic patients who were anticoagulated showed a trend toward greater neurologic improvement at the time of discharge than those who were not anticoagulated. CONCLUSIONS: Screening allows the identification of asymptomatic BCI and thereby facilitates early systemic anticoagulation, which is associated with improved neurologic outcome. The role of endovascular stents in the treatment of blunt traumatic pseudoaneurysms remains to be defined.
Biffl, W L; Moore, E E; Ryu, R K; Offner, P J; Novak, Z; Coldwell, D M; Franciose, R J; Burch, J M
Sequential-Design, Multicenter, Randomized, Controlled Trial of Early Decompressive Craniectomy in Malignant Middle Cerebral Artery Infarction (DECIMAL Trial)
Background and Purpose—There is no effective medical treatment of malignant middle cerebral artery (MCA) infarction. The purpose of this clinical trial was to assess the efficacy of early decompressive craniectomy in patients with malignant MCA infarction. Methods—We conducted in France a multicenter, randomized trial involving patients between 18 and 55 years of age with malignant MCA infarction to compare functional
Katayoun Vahedi; Eric Vicaut; Joaquim Mateo; Annie Kurtz; Mikael Orabi; Jean-Pierre Guichard; Carole Boutron; Gregory Couvreur; Francois Rouanet; Emmanuel Touze ´; Benoît Guillon; Alexandre Carpentier; Alain Yelnik; Bernard George; Didier Payen; Marie-Germaine Bousser
Enhanced susceptibility-weighted angiography (ESWAN) of cerebral arteries and veins at 1.5 Tesla.
Objective: Enhanced susceptibility-weighted angiography (ESWAN) is a three-dimensional (3D) multi-echo gradient-echo sequence which consists of both magnitude and phase images. This study aims to demonstrate the feasibility of ESWAN for the depiction of both cerebral arteries and veins at 1.5?T by comparing with time-of-flight (TOF) MR angiography (MRA) and MR venography (MRV). Methods: 13 healthy volunteers underwent both ESWAN and 3D-TOF-MRA examinations. Among them, nine volunteers underwent an additional two-dimensional-TOF-MRV examination. With regard to the ESWAN sequence, both maximum intensity projection (MIP) and minimum intensity projection (mIP) images were reconstructed and compared with MIP reconstructions of the TOF MRA and the TOF MRV. Results: Concerning the depiction of the constituent segments of the Circle of Willis, as well as A1, A2, A3 (segments of the anterior cerebral artery), M1, M2 (segments of the middle cerebral artery), P1 and P2 (segments of the posterior cerebral artery), the value of the ESWAN MIP was comparable to that of the TOF MRA without regard to visualization of branches, vessel homogeneity and wall irregularities or slight stenosis. ESWAN-mIP visualized more deep cerebral veins than TOF MRV in this study. Conclusion: By use of either mIP reconstruction of a long echo data set or MIP reconstruction of a short echo data set, ESWAN allows simultaneous visualization of both cerebral veins and proximal segments of intracerebral arteries at 1.5?T. Advances in knowledge: ESWAN acquires multiple images at different echo times corresponding to different T2* weightings, wherein a short echo TOF-MRA data set and a long echo susceptibility-weighted imaging-MRV data set are obtained simultaneously. PMID:24786315
Chen, L; Zhang, J; Wang, Q-X; Peng, L; Luo, X; Zhu, W-Z; Roshan, A K; Qi, J-P; Wang, H
A comparison of early mortality and morbidity after single and bilateral internal mammary artery grafting with the free right internal mammary artery.
OBJECTIVE--To compare differences in early mortality and morbidity in patients receiving a single internal mammary artery graft (SIMA) with those receiving bilateral internal mammary artery grafts (BIMA) with a free right internal mammary artery (RIMA). DESIGN--Retrospective analysis of 150 patients undergoing BIMA grafting between 1989-1992 who were carefully matched with 150 patients undergoing SIMA grafting between 1987-1992 for known cardiovascular risk factors, extent of coronary disease, left ventricular function, and number of coronary grafts. Operative variables noted included aortic cross clamp time and bypass time. Postoperative cardiac, respiratory, and wound complications were also noted. RESULTS--Operative mortality was 2% in the SIMA group and 1.3% in the BIMA group (NS). Other than the prevalence of ventricular arrhythmias (P = 0.025), which were more common in the BIMA group, there were no significant differences between the two groups in terms of postoperative morbidity. At median (interquartile range) follow up of 27.94(0.86) and 23.94(0.74) months for the SIMA and BIMA groups respectively there were no deaths. 87% of the SIMA group and 91% of the BIMA group were free of symptoms at follow up. CONCLUSIONS--The earlier fears regarding increased early mortality and morbidity after BIMA surgery were not confirmed by this study. All patients receiving both mammary arteries had a free rather than pedicle right internal mammary graft. The early mortality and morbidity reported here compares favourably with previous reports on the use of a pedicle graft.
Ashraf, S S; Shaukat, N; Akhtar, K; Love, H; Shaw, J; Rowlands, D J; Keenan, D
Imaging the basilar artery by contrast-enhanced color-coded ultrasound.
Conventional transcranial color-coded real-time sonography of the vertebrobasilar system is limited by imaging problems of the distal segment of the basilar artery. Lung-stable contrast-enhancing agents may overcome this problem by enhancing the quality of Doppler signals by as much as 20%. Fourty-two patients underwent sonographic evaluation of the vertebrobasilar system before and after receiving intravenously administered galactose-based contrast-enhancing agent Levovist by transforaminal and transtemporal routes. Imaging quality was classified into five categories depending on the length of visible color-flow by transforaminal approach: 1--no signal, 2--1-9.9 mm, 3--10-19.9 mm, 4--20-29.9 mm, 5--> or = 30 mm. For transtemporal insonation, imaging quality was classified either as no color flow or sufficient color flow of the basilar tip. By unenhanced investigation, average signal length of color flow was 16 +/- 8 mm for transforaminal investigation; application of Levovist improved this value to 26.6 +/- 6 mm. For unenhanced transforminal approach, 4.8% were assigned to category 1, 11.9% to category 2, 54.8% to category 3, 23.8% to category 4 and 4.8% to category 5. After signal enhancement with Levovist, category 1 covered 0%, category 2 2.4%, category 3 7.14%, category 4 59.5% and category 5 30.9% (p < 0.001). Unenhanced transtemporal approach allowed identification of the basilar tip in 78.6% with an average length of 6.3 +/- 2 mm; contrast enhancement improved this values to 92.9% and 8.3 +/- 3.3 mm respectively (p < 0.05). The application of transpulmonary contrast-enhancing agents improves the reliability of transcranial color-coded duplex sonography of the basilar artery. PMID:11147396
Iglseder, B; Huemer, M; Staffen, W; Ladurner, G
Disproportionate pulmonary hypertension in a patient with early-onset pulmonary emphysema treated with specific drugs for pulmonary arterial hypertension.
Severe pulmonary hypertension in chronic obstructive pulmonary disease (COPD) is referred to as 'disproportionate' because the elevated pulmonary artery pressure does not match the degree of air flow limitation. We report a 41-year-old man presenting with early-onset pulmonary emphysema and pulmonary hypertension with a mean pressure of 74 mmHg. Continuous intravenous epoprostenol led to marked hemodynamic improvement, and epoprostenol was successfully replaced with bosentan. The patient has been followed for 3 years without exacerbation. This is the first report demonstrating the long-term efficacy of specific drugs for pulmonary arterial hypertension in disproportionate pulmonary hypertension in COPD. PMID:22001462
Shimizu, Masatoshi; Imanishi, Junichi; Takano, Takatsugu; Miwa, Yoichi
New phenotypic aspects of the decidual spiral artery wall during early post-implantation mouse pregnancy
Highlights: Black-Right-Pointing-Pointer Spiral artery (SA) wall remodeling (SAR) is ill-defined and clinically important. Black-Right-Pointing-Pointer SA muscular phenotype prior to and during SAR in mice is underexplored. Black-Right-Pointing-Pointer SA muscular wall consists of contractile and non-contractile components. Black-Right-Pointing-Pointer SA wall non-contractile component may be synthetic smooth muscle. Black-Right-Pointing-Pointer Timing and extent of SA wall contractile component loss is revealed. -- Abstract: During pregnancy the walls of decidual spiral arteries (SAs) undergo clinically important structural modifications crucial for embryo survival/growth and maternal health. However, the mechanisms of SA remodeling (SAR) are poorly understood. Although an important prerequisite to this understanding is knowledge about the phenotype of SA muscular wall prior to and during the beginning of mouse SAR, this remains largely unexplored and was the main aim of this work. Using histological and immunohistochemical techniques, this study shows for the first time that during early mouse gestation, from embryonic day 7.5 (E7.5) to E10.5, the decidual SA muscular coat is not a homogeneous structure, but consists of two concentric layers. The first is a largely one cell-thick sub-endothelial layer of contractile mural cells (positive for {alpha}-smooth muscle actin, calponin and SM22{alpha}) with pericyte characteristics (NG2 positive). The second layer is thicker, and evidence is presented that it may be of the synthetic/proliferative smooth muscle phenotype, based on absence ({alpha}-smooth muscle actin and calponin) or weak (SM22{alpha}) expression of contractile mural cell markers, and presence of synthetic smooth muscle characteristics (expression of non-muscle Myosin heavy chain-IIA and of the cell proliferation marker PCNA). Importantly, immunohistochemistry and morphometrics showed that the contractile mural cell layer although prominent at E7.5-E8.5, becomes drastically reduced by E10.5 and is undetectable by E12.5. In conclusion, this study reveals novel aspects of the decidual SA muscular coat phenotype prior to and during early SAR that may have important implications for understanding the mechanisms of SAR.
Elia, Artemis; Charalambous, Fotini [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)] [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus); Georgiades, Pantelis, E-mail: email@example.com [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)] [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)
Brachial Artery Endothelial Responses during Early Recovery from an Exercise Bout in Patients with Coronary Artery Disease
This study examined the acute endothelial responses to an exercise bout in coronary artery disease (CAD) patients. Nineteen males with CAD (63 ± 8 years) were assessed at rest and 15 minutes following a submaximal exercise bout (recovery). Brachial artery endothelial-dependent function was assessed using flow-mediated dilation (FMD). Brachial artery diameters and velocities were measured using Duplex ultrasound at baseline, and for 3 minutes following a 5-minute ischemic period. Endothelial-independent function was assessed using a 0.4?mg dose of nitroglycerin (NTG). FMD responses were unchanged from rest to recovery; however, there were 2 types of responses: negative and positive FMD responders. Post-hoc analysis revealed that positive responders had lower resting FMD compared to negative responders (3.2 ± 1.7 versus 6.0 ± 2.5%, P < 0.05). NTG-mediated dilation was reduced in recovery (22.0 ± 5.6 versus 14.4 ± 5.7%, P < 0.001 for rest versus recovery). In conclusion, acute endothelial-dependent responses to submaximal exercise are affected by the degree of resting endothelial dysfunction. The observation of attenuated NTG-mediated dilation during recovery is novel and warrants the investigation of possible mechanisms and clinical significance. Furthermore, it highlights the necessity of both endothelial-dependent and endothelial-independent assessments when evaluating endothelial function changes with an intervention.
Currie, Katharine D.; McKelvie, Robert S.; MacDonald, Maureen J.
Do Prekindergarten Teachers Design Their Classrooms to Enhance Early Literacy?
ERIC Educational Resources Information Center
Young children develop language and early literacy interactions that are the building blocks for future skilled reading. This study was designed to evaluate the early childhood classroom to determine teachers? knowledge of early literacy. Based on the Literacy Environment Checklist (LEC) of the Early Literacy and Language Classroom Observation…
LoRusso, Jo Ann D.
Diagnostic classification of arterial spin labeling and structural MRI in presenile early stage dementia.
Because hypoperfusion of brain tissue precedes atrophy in dementia, the detection of dementia may be advanced by the use of perfusion information. Such information can be obtained noninvasively with arterial spin labeling (ASL), a relatively new MR technique quantifying cerebral blood flow (CBF). Using ASL and structural MRI, we evaluated diagnostic classification in 32 prospectively included presenile early stage dementia patients and 32 healthy controls. Patients were suspected of Alzheimer's disease (AD) or frontotemporal dementia. Classification was based on CBF as perfusion marker, gray matter (GM) volume as atrophy marker, and their combination. These markers were each examined using six feature extraction methods: a voxel-wise method and a region of interest (ROI)-wise approach using five ROI-sets in the GM. These ROI-sets ranged in number from 72 brain regions to a single ROI for the entire supratentorial brain. Classification was performed with a linear support vector machine classifier. For validation of the classification method on the basis of GM features, a reference dataset from the AD Neuroimaging Initiative database was used consisting of AD patients and healthy controls. In our early stage dementia population, the voxelwise feature-extraction approach achieved more accurate results (area under the curve (AUC) range?=?86?-?91%) than all other approaches (AUC?=?57?-?84%). Used in isolation, CBF quantified with ASL was a good diagnostic marker for dementia. However, our findings indicated only little added diagnostic value when combining ASL with the structural MRI data (AUC?=?91%), which did not significantly improve over accuracy of structural MRI atrophy marker by itself. Hum Brain Mapp 35:4916-4931, 2014. © 2014 Wiley Periodicals, Inc. PMID:24700485
Bron, Esther E; Steketee, Rebecca M E; Houston, Gavin C; Oliver, Ruth A; Achterberg, Hakim C; Loog, Marco; van Swieten, John C; Hammers, Alexander; Niessen, Wiro J; Smits, Marion; Klein, Stefan
Withdrawal of magnesium enhances coronary arterial spasms produced by vasoactive agents.
1 The influence of external magnesium ions ([Mg2+]o) on the sensitivity (i.e. EC50) and contractility (maximum response) of isolated large and small coronary arteries of the dog, obtained from different regions of the myocardium, to vasoactive agents was studied. 2 Removal of [Mg2+]o from the physiological salt solution enhanced, while elevation in [Mg2+]o to 4.8 mM, lowered the contractile sensitivity to three different agents, 5-hydroxytryptamine (5-HT), angiotensin II and KCl. 3 Contractility, of both large and small coronary arteries, to 5-HT and angiotensin II was potentiated and depressed, respectively, by withdrawal and elevation of [Mg2+]o; maximum responses to KCl were not altered by 0 or 4.8 mM [Mg2+]o. 4 Cumulative concentration-contractile effect curves to CaCl2 were shifted leftward on removal of [Mg2+]o; elevation of [Mg2+]o to 4.8 mM shifted the CaCl2 concentration-effect curves to the right. Maximal contractile responses to CaCl2 were enhanced by removal of, and reduced by elevation of, [Mg2+]o. 5 The calcium channel blocking agent, verapamil (10(-6)M), inhibited completely contractile responses to KCl; contractile responses elicited by angiotensin II and 5-HT were attenuated by verapamil. 6 A variety of pharmacological antagonists (phentolamine, propranolol, methysergide, atropine, diphenhydramine), as well as use of a prostaglandin cyclo-oxygenase inhibitor, did not modify the altered contractile responses evoked by angiotensin II or KCl in different concentrations of Mg2+. 7 These results suggest: (1) [Mg2+]o may exert considerably greater influence on receptor-operated rather than membrane-potential sensitive channels involved in Ca2+ transport in coronary arterial smooth muscle; (2) Mg2+ interferes with the affinity (binding) of certain agonists (5-HT and angiotensin II) for their respective receptors in coronary vascular muscle; and (3) a functional pool of Ca2+ which is resistant to Ca2+-depletion, but accessible to activation by 5-HT and angiotensin II is present in canine coronary arterial smooth muscle.
Altura, B. M.; Turlapaty, P. D.
Causes of death in early MI survivors with persistent infarct artery occlusion: results from the Occluded Artery Trial (OAT)
Aims OAT randomised patients with an occluded infarct artery three to 28 days after myocardial infarction (MI). The study demonstrated that PCI did not reduce the occurrence of the primary composite endpoint of death, re-MI, and New York Heart Association class IV heart failure in comparison with patients assigned to optimal medical therapy alone (MED). In view of prior literature in similar cohorts showing fewer sudden cardiac deaths and less left ventricular (LV) remodelling, but excess re-MI with PCI, causes of death were analysed in more detail. Methods and results Stepwise Cox regression was used to examine baseline variables associated with causes of death. The immediate and primary cause of death did not differ between 1,101 PCI and 1,100 MED patients. One-year cardiovascular death rates were 3.8% for the PCI group, and 3.7% for the MED group, and 0.9% per year for the next four years in both groups. Five of six cases of cardiac rupture occurred in patients undergoing PCI. Conclusions In stable post-MI patients with occlusion of the infarct-related artery, PCI did not change the rate or cause of death. The observation that the majority of cardiac ruptures occurred in patients undergoing PCI deserves further investigation.
Lang, Irene M.; Forman, Sandra A.; Maggioni, Aldo P.; Ruzyllo, Witold; Renkin, Jean; Vozzi, Carlos; Steg, P. Gabriel; Hernandez-Garcia, Jose-Maria; Zmudka, Krzysztof; Jimenez-Navarro, Manuel; Sopko, George; Lamas, Gervasio A.; Hochman, Judith S.
Blood flow parameters of the superior mesenteric artery as an early predictor of intestinal dysmotility in preterm infants
BackgroundBlood flow parameters in the superior mesenteric artery (SMA) change with vasoconstriction or vasodilatation of the intestinal vascular bed. In cases of severe growth retardation as a result of haemodynamic disturbances, the blood flow changes persist into postnatal life.ObjectiveTo assess early changes of Doppler sonographic blood flow parameters in the SMA for prediction of later intestinal motility disturbances in preterm
Eva Robel-Tillig; Matthias Knüpfer; Ferdinand Pulzer; Christoph Vogtmann
Comparison of early and 1-year follow-up results of conventional hemorrhoidectomy and hemorrhoid artery ligation: a randomized study
Background and aimsDoppler-guided hemorrhoid artery ligation is a new approach for treating hemorrhoids. Early and 1-year follow-up results of the procedure are presented and compared with those of closed scissors hemorrhoidectomy in a prospective randomized study.Patients and methodsSixty consecutively recruited patients were randomized into two groups: group A ( n=30) was treated with standardized closed scissors hemorrhoidectomy and group B
Attila Bursics; Krisztina Morvay; Péter Kupcsulik; Lajos Flautner
A common variant on chromosome 9p21 affects the risk of early-onset coronary artery disease
Background Two single nucleotide polymorphisms (SNPs, rs10757278 and rs2383207) on chromosome 9p21 have been proved to be associated\\u000a with myocardial infarction. We investigated whether these two genetic markers are determinants of early-onset coronary artery\\u000a disease. Methods and results A total of 444 consecutive patients were studied including 212 cases with coronary stenosis ?50% or previous myocardial infarction and 232 controls without
Zhong Chen; Qi Qian; Genshan Ma; Jiahong Wang; Xiaoli Zhang; Yi Feng; Chengxing Shen; Yuyu Yao
Gadolinium-enhanced magnetic resonance (Gd-MR) as first approach in the diagnosis of renal artery stenosis
End stage renal disease is caused by ischemic nephropathy almost in 22% of patients over 50 years old starting hemodialysis treatment. The early diagnosis could avoid the progression of renal insufficiency in many cases. The gold standard in the diagnosis of renal artery stenosis is digital subtractive arteriography (DSA), which represents a severe risk of progression of renal failure for
Elisabetta Rubbiani; Carmela Giovannone; Filomena Di Bari; Paola Inguaggiato; Alberto Albertazzi; Stefano Colopi; Emilio Cerofolini; Mauro Marchetti; Ennio Gallo
Early Repolarization and Myocardial Scar Predict Poorest Prognosis in Patients with Coronary Artery Disease
Purpose Recent studies show positive association of early repolarization (ER) with the risk of life-threatening arrhythmias in patients with coronary artery disease (CAD). This study was to investigate the relationships of ER with myocardial scarring and prognosis in patients with CAD. Materials and Methods Of 570 consecutive CAD patients, patients with and without ER were assigned to ER group (n=139) and no ER group (n=431), respectively. Myocardial scar was evaluated using cardiac single-photon emission computed tomography. Results ER group had previous history of myocardial infarction (33% vs. 15%, p<0.001) and lower left ventricular ejection fraction (57±13% vs. 62±13%, p<0.001) more frequently than no-ER group. While 74 (53%) patients in ER group had myocardial scar, only 121 (28%) patients had in no-ER group (p<0.001). During follow up, 9 (7%) and 4 (0.9%) patients had cardiac events in ER and no-ER group, respectively (p=0.001). All patients with cardiac events had ER in inferior leads and horizontal/descending ST-segment. Patients with both ER in inferior leads and horizontal/descending ST variant and scar had an increased adjusted hazard ratio of cardiac events (hazard ratio 16.0; 95% confidence interval: 4.1 to 55.8; p<0.001). Conclusion ER in inferior leads with a horizontal/descending ST variant was associated with increased risk of cardiac events. These findings suggest that ER in patients with CAD may be related to myocardial scar rather than pure ion channel problem.
Lee, Hye-Young; Mun, Hee-Sun; Wi, Jin; Uhm, Jae-Sun; Shim, Jaemin; Kim, Jong-Youn; Pak, Hui-Nam; Lee, Moon-Hyoung
No Evidence for Activated Autophagy in Left Ventricular Myocardium at Early Reperfusion with Protection by Remote Ischemic Preconditioning in Patients Undergoing Coronary Artery Bypass Grafting
Objective Remote ischemic preconditioning (RIPC) by repeated brief limb ischemia/reperfusion reduces myocardial injury in patients undergoing coronary artery bypass grafting (CABG). Activation of signal transducer and activator of transcription 5 (STAT5) in left ventricular (LV) myocardium at early reperfusion is associated with such protection. Autophagy, i.e., removal of dysfunctional cellular components through lysosomes, has been proposed as one mechanism of cardioprotection. Therefore, we analyzed whether or not the protection by RIPC is associated with activated autophagy. Methods CABG patients were randomized to undergo RIPC (3×5 min blood pressure cuff inflation/5 min deflation) or placebo (cuff deflated) before skin incision (n?=?10/10). Transmural myocardial biopsies were taken from the LV before cardioplegia (baseline) and at early (5–10 min) reperfusion. RIPC-induced protection was reflected by decreased serum troponin I concentration area under the curve (194±17 versus 709±129 ng/ml × 72 h, p?=?0.002). Western blotting for beclin-1-phosphorylation and protein expression of autophagy-related gene 5–12 (ATG5-12) complex, light chain 3 (LC3), parkin, and p62 was performed. STAT3-, STAT5- and extracellular signal-regulated protein kinase 1/2 (ERK1/2)-phosphorylation was used as positive control to confirm signal activation by ischemia/reperfusion. Results Signals of all analyzed autophagy proteins did not differ between baseline and early reperfusion and not between RIPC and placebo. STAT5-phosphorylation was greater at early reperfusion only with RIPC (2.2-fold, p?=?0.02). STAT3- and ERK1/2-phosphorylation were greater at early reperfusion with placebo and RIPC (?2.7-fold versus baseline, p?0.05). Conclusion Protection through RIPC in patients undergoing CABG surgery does not appear to be associated with enhanced autophagy in LV myocardium at early reperfusion.
Gedik, Nilgun; Thielmann, Matthias; Kottenberg, Eva; Peters, Jurgen; Jakob, Heinz; Heusch, Gerd; Kleinbongard, Petra
Accuracy of Contrast-Enhanced MR Angiography in Predicting Angiographic Stenosis of the Internal Carotid Artery: Linear Regression Analysis
BACKGROUND AND PURPOSE: We sought to assess whether contrast-enhanced MR an- giography is able to predict the degree of angiographic stenosis of the internal carotid artery within a clinically acceptable margin of error, thereby decreasing the need for angiography. In addition, we sought to assess whether adding ultrasound peak systolic velocity (PSV) as an additional regressor improves the accuracy of
Gasser M Hathout; Michael J. Duh; Suzie M. El-Saden
Early repolarization: an electrocardiographic predictor of enhanced aerobic fitness.
The presence or absence of early repolarization on the electrocardiogram at rest was correlated with aerobic exercise capacity in healthy volunteers from the Baltimore Longitudinal Study of Aging. Patients with early repolarization had both longer treadmill exercise duration and higher peak oxygen consumption than age-and gender-matched control subjects. PMID:10955390
Haydar, Z R; Brantley, D A; Gittings, N S; Wright, J G; Fleg, J L
Umbilical artery pH at birth and neurobehavioral outcome in early preterm infants: A cohort study
Objective: The objective of the following study is to determine the effect of umbilical artery pH at birth on early neurobehavioral outcome of preterm infants as assessed by Neurobehavioral Assessment of Preterm Infants (NAPI) tool. Materials and Methods: Prospective cohort study conducted at the neonatal unit in a tertiary care center in North India. Preterm neonates < 34 weeks of gestation were enrolled at birth and divided into cases (umbilical artery pH < 7.2) and controls (umbilical artery pH > 7.2). At 34 weeks postconceptional age, the motor development and vigor (MDV) and alertness and orientation (AO) domains of neurobehavior were assessed by NAPI and compared among groups. Results: Hundred preterm neonates were enrolled in the study out of which 76 (30 cases and 46 controls) were finally analyzed. The groups were comparable in terms of gestational age, mode of delivery, birth weight and requirement of resuscitative measures at birth. There was no significant difference in incidence of meningitis, intraventricular hemorrhage, jaundice and hypoxic ischemic encephalopathy among the groups; however hypoglycemia was observed more commonly among cases. The MDV score (mean ± standard deviation [SD] [95% confidence interval]) was found to be significantly lower among cases compared to controls (37.0713 ± 13.616 [32.099-42.0431] vs. 47.506 ± 14.0692 [43.367-51.655]) (P = 0.002). Similarly, lower AO scores were observed among the cases. Conclusion: A low umbilical artery pH at birth is a predictor of poor early neurobehavioral outcome in preterm neonates.
Seth, Bhavna; Datta, Vikram; Bhakhri, Bhanu Kiran
Identification of early complications following pancreas and renal transplantation using contrast enhanced ultrasound (CEUS) - first results.
AIM: Identification of acute and subacute complications following pancreas and renal transplantation using contrast enhanced ultrasound (CEUS) in comparison with Magnetic Resonance Tomography (MRI), Computed Tomography (CT), Digital Subtraction Angiography (DSA) or Ultrasound (US). The study evaluated whether CEUS could confirm the preliminary diagnosis or even provide additional information, relevant for the therapeutic strategy. MATERIAL AND METHODS: Retrospective evaluation of 19 patients (13 male, 6 female, age 26-77 years, mean 53.2 years) following renal transplantation and 10 patients (4 male, 6 female, age 35-56 years, mean 45.7 years) following combined pancreas and renal transplantation. CEUS was used as an additional diagnostic method when obscure diagnostic findings occurred in US, CT, MRI or DSA. Fundamental B-scan, Color Coded Doppler Sonography (CCDS) and CEUS were performed in all patients by an experienced examiner using a multifrequency convex transducer (1-5 MHz). After a bolus injection of up to 2.4 ml SonoVue® [BRACCO, Italy] digital raw data was stored as cine-loops up to 5 minutes in length. RESULTS: In all patients, the pathological features and suspected diagnostic findings identified in the other imaging modalities could be confirmed using CEUS (100%). In 25 out of 29 patients (86.2%), new clinically relevant findings were detected. In 27 patients, the diagnosis of CEUS was confirmed during surgery (7), DSA (5), follow-up CEUS (13), CT (1) and MRI (1). In 4 patients renal AV-fistulas were found following biopsy, 3 patients showed post-operative allograft arterial stenosis or dissection, 1 patient demonstrated a stenosis of the common iliac artery and 2 patients were diagnosed with post-operative allograft venous thrombosis or stenosis. In 2 patients, a definite diagnosis of a benign lesion following renal transplantation was possible. In 1 patient a malignant lesion was suspected and confirmed following surgery. In 6 patients, normal perfusion of the pancreas and renal parenchyma and the corresponding vessels was diagnosed, in 5 patients the parenchymal perfusion was diminished and 1 patient suffered from pancreatitis. CONCLUSION: These first results show that CEUS can provide additional, clinically relevant informations in patients with acute and subacute complications following pancreas and renal transplantation. Thus, an early application within the diagnostic course seems favorable. PMID:23380964
Rennert, Janine; Farkas, Stefan; Georgieva, Martina; Loss, Martin; Dornia, Christian; Jung, Wolfgang; Stroszczynski, Christian; Jung, Ernst-Michael
Role of the cytomegalovirus major immediate early enhancer in acute infection and reactivation from latency
The cytomegalovirus (CMV) major immediate early (MIE) enhancer-containing promoter regulates the expression of the downstream\\u000a MIE genes, which have critical roles in reactivation from latency and acute infection. The enhancer consists of binding sites\\u000a for cellular transcription factors that are repeated multiple times. The primate and nonprimate CMV enhancers can substitute\\u000a for one another. The enhancers are not functionally equivalent,
Mark F. Stinski; Hiroki Isomura
Echocardiography may help detect pulmonary vasculopathy in the early stages of pulmonary artery hypertension associated with systemic sclerosis
Background Pulmonary arterial hypertension (PAH) in patients with systemic sclerosis is associated with a poor prognosis, but this can be improved by early disease detection. Abnormal pulmonary and cardiac function can be detected early by means of echocardiography, whereas right heart catheterization is usually performed later. Objectives The purpose of this prospective study was to detect early the presence of pulmonary artery vasculopathy in patients with verified systemic sclerosis without significant pulmonary fibrosis, normal lung volumes and a mildly reduced lung diffusion capacity of carbon monoxide (DLCO). Methods Nineteen consecutive female NYHA class I-II patients with scleroderma and a PAPs of < 35 mm/Hg measured by echocardiography, were enrolled between September 2007 and September 2009. They had a mean age of 51 ± 13 years, body mass index of 25 ± 5 kg/m2). They all underwent complete Doppler echocardiography, CPET, a pulmonary ventilation test (carbon monoxide lung diffusion, DLCO), HRCT. To investigate PAH by means of complete resting Doppler echocardiography estimates of systolic pulmonary artery pressure (PAPs) derived from tr icuspid regurgitation, mean PAP derived from pulmonary regurgitation, pulmonary vessel resistance (PVR) derived from the acceleration time of the pulmonary outflow tract (ACTpo), and right ventricular function derived from tricuspid annular plane systolic excursion (TAPSE). Right heart catheterisation was conducted only, if pulmonary hypertension was suggested by echocardiography and an abnormal ventilator test. The data are given as mean values ± SD, unless otherwise stated. The correlations between the variables were analysed using Pearson's r coefficient, and the predictive value of the variables was calculated using linear regression analysis. A p value of > 0.05 was considered significant. Results Right heart catheterization detected PAH in 15/19 patients; mean PAP was 30.5 mm/Hg and RVP 3.6 UW. Coronary angiography of the patients aged more than 55 years showed some evidence of significant coronary artery disease. Echocardiography showed high systolic PAP values (46 ± 8 mmHg), whereas right ventricular function was normal (TAPSE 23 ± 3 mm), and in line with the NYHA class. ACTpo was reduced in the patients with a systolic PAP of < 46 mm/Hg (p > 0.001) and positively correlated with DLCO (p > 0.001) and the hemodynamic data. There was a good correlation between ACTpo and PVR (hemodynamic data) (r = -0615; p > 0.01). Conclusions Although they need to be confirmed by studies of larger series of patients, our findings suggest that, in comparison with hemodynamic data, non-invasive echocardiographic measurements are an excellent means of identifying early-stage PAH.
Cutting-Balloon Angioplasty in Transplant Renal Artery Stenosis as First-Line Treatment in the Early Postoperative Period
Percutaneous transluminal angioplasty has been successfully used for the treatment of transplant renal artery stenosis (RAS). Cutting-balloon angioplasty (CBA) is being used as a second option in pressure-resistant stenosis. It is thought that CBA is less traumatic and therefore restenosis occurs less frequently than in conventional angioplasty. This case report describes the unusual use of a cutting balloon in transplant RAS as a first option in the early postoperative period. Long-term follow-up data are also presented.
Ucar, Adem, E-mail: firstname.lastname@example.com [Istanbul University, Interventional Radiology Department, Istanbul Faculty of Medicine (Turkey); Yahyayev, Aghakishi, E-mail: email@example.com [Istanbul University, Radiology Department, Istanbul Faculty of Medicine (Turkey); Bakkaloglu, Huseyin, E-mail: firstname.lastname@example.com [Istanbul University, Transplantlogy Department, General Surgery, Istanbul Faculty of Medicine (Turkey); Agayev, Ayaz, E-mail: email@example.com [Istanbul University, Radiology Department, Istanbul Faculty of Medicine (Turkey); Aydin, Ali Emin, E-mail: firstname.lastname@example.com [Istanbul University, Transplantlogy Department, General Surgery, Istanbul Faculty of Medicine (Turkey); Rozanes, Izzet, E-mail: email@example.com [Istanbul University, Interventional Radiology Department, Istanbul Faculty of Medicine (Turkey)
Conservative approach for perforation and early pseudoaneurysm of left anterior descending artery during overlapped stenting.
Coronary artery perforation rarely occurs during or following percutaneous coronary intervention. Its consequences may range from minimal dye staining to tamponade and abrupt hemodynamic collapse. Coronary perforation during angioplasty can evolve into pseudoaneurysm. We report a case in which a vessel perforation and pseudoaneurysm were formed in the mid-portion of the left anterior descending artery during overlapped stenting. The perforation was sealed by inflating the angioplasty balloon. The patient was followed by angiography and intravascular ultrasound. After 1-week observation, the pseudoaneurysm was completely resolved. PMID:19411731
Alidoosti, Mohammad; Soleimani, Abbas; Abbasi, Ali
Carotid artery stenosis: contrast-enhanced MR angiography with two different scan times compared with digital subtraction angiography.
Contrast enhanced magnetic resonance angiography (CE MRA) is a non-invasive alternative to conventional digital subtraction angiography (DSA). CE MRA is increasingly used as a complement to Duplex in the preoperative assessment of carotid artery stenosis. The purpose of this study was to determine if CE MRA could replace preoperative DSA. CE MRA with a scan time of 10 or 28 s was performed in 24 consecutive patients who were scheduled for preoperative DSA because of Duplex-verified severe carotid artery stenosis. Two neuroradiologists measured the degree of stenosis with three different methods, and the image quality was evaluated. DSA was used as the gold standard. For detection of severe stenosis (N. American symptomatic carotid endarterectomy trial (NASCET) > or =70%; European symptomatic carotid endarterectomy trial (ECST) > or =80%; common carotid artery method (CCAM) > or =80%), the sensitivity of CE MRA maximum intensity projection (MIP) compared with DSA was 82%-100 %, the specificity was 74%-93% and the accuracy was 77%-90%. The inter-observer agreement was higher, the image quality was better and the intracranial main arteries were better visualized with the 28 s than with the 10 s scan time. The enhancement of the jugular veins seen in 17% of the 10 s scans and in 58% of the patients with the 28 s scans did not interfere with the evaluation of the carotid arteries. CE MRA, preferably with a scan time of 28 s, can replace DSA in the preoperative assessment of most patients with carotid artery stenosis. PMID:12136361
Sundgren, P C; Sundén, P; Lindgren, A; Lanke, J; Holtĺs, S; Larsson, E-M
Arterial ageing is characterized by age associated degeneration and sclerosis of the media layer of the large arteries. However, besides ageing, clinical conditions, which enhance oxidative stress and inflammation act to accelerate the degree of arterial ageing. In this review, we summarized the pathophysiology and contributing factors that accelerate arterial ageing. Among them, we focused on hypertension, the renin-angiotensin-aldosterone system and vascular inflammation which are modifiable causes of the arterial ageing process. Also, novel treatment targets derived from the disease models such as the Hutchinson Gilford Progeria Syndrome were reviewed.
Lee, Seung-Jun
ACE inhibition enhances bradykinin relaxations through nitric oxide and B1 receptor activation in bovine coronary arteries
Bradykinin causes vascular relaxations through release of endothelial relaxing factors including prostacyclin, nitric oxide (NO) and epoxyeicosatrienoic acids (EETs). Bradykinin is metabolized by angiotensin converting enzyme (ACE) and ACE inhibition enhances bradykinin relaxations. Our goal was to characterize the role of bradykinin receptors and endothelial factors in ACE inhibitor-enhanced relaxations in bovine coronary arteries. In U46619 preconstricted arteries, bradykinin (10?11?10?8M) caused concentration-dependent relaxations (maximal relaxation ?100%, log EC50=?9.8±0.1). In the presence of the NO synthase inhibitor, N-nitro-L-arginine (L-NA, 30 µM) and the cyclooxygenase inhibitor, indomethacin (10 µM), relaxations were reduced by an inhibitor of EET synthesis, miconazole (10 µM) (maximal relaxation =55±10%). Bradykinin relaxations were inhibited by the bradykinin 2 (B2) receptor antagonist, D-Arg0-Hyp3-Thi5,8-D-Phe7-bradykinin (1 µM) (log EC50=?8.5±0.1) but not altered by the B1 receptor antagonist, des-Arg9[Leu8]bradykinin (1 µM). Mass spectrometric analysis of bovine coronary artery bradykinin metabolites revealed a time-dependent increase in bradykinin (1–5) and (1–7) suggesting metabolism by ACE. ACE inhibition with captopril (50 µM) enhanced bradykinin relaxations (log EC50=?10.3±0.1). The enhanced relaxations were eliminated by L-NA, the B1 receptor antagonist but not the B2 receptor antagonist. Our results demonstrate that ACE inhibitor-enhanced bradykinin relaxations of bovine coronary arteries occur through endothelial cell B1 receptor activation and NO.
Gauthier, Kathryn M.; Cepura, Cody J.; Campbell, William B.
Interobserver Agreement in Assessing Early CT Signs of Middle Cerebral Artery Infarction
PURPOSE: To assess the reliability of detecting signs of hemispheric infarction on CT scans obtained within 6 hours of the onset of symptoms. METHODS: A neuroradiologist selected 12 normal and 33 abnormal CT studies showing the hyperdense middle cerebral artery sign (HMCAS) (n 5 10), brain swelling (n 5 22), and parenchymal hypodensity (n 5 33) from two series of
Rudiger von Kummer; Rolf Holle; Ulrich Grzyska; Erich Hofmann; Olav Jansen; Dirk Petersen; Martin Schumacher; Klaus Sartor
Blind estimation of the arterial input function in dynamic contrast-enhanced MRI using purity maximization.
Uncertainty in arterial input function (AIF) estimation is one of the major errors in the quantification of dynamic contrast-enhanced MRI. A blind source separation algorithm was proposed to determine the AIF by selecting the voxel time course with maximum purity, which represents a minimal contamination from partial volume effects. Simulations were performed to assess the partial volume effect on the purity of AIF, the estimation accuracy of the AIF, and the influence of purity on the derived kinetic parameters. In vivo data were acquired from six patients with hypopharyngeal cancer and eight rats with brain tumor. Results showed that in simulation the AIF with the highest purity is closest to the true AIF. In patients, the manually selection had reduced purity, which could lead to underestimations of K(trans) and V(e) and an overestimation of V(p) when compared with those obtained by the proposed blind source separation algorithm. The derived kinetic parameters in the tumor were more susceptible to the changes in purity when compared with those in the muscle. The animal experiment demonstrated good reproducibility in blind source separation-AIF derived parameters. In conclusion, the blind source separation method is feasible and reproducible to identify the voxel with the tracer concentration time course closest to the true AIF. PMID:22383386
Lin, Yu-Chun; Chan, Tsung-Han; Chi, Chong-Yung; Ng, Shu-Hang; Liu, Hao-Li; Wei, Kuo-Chen; Wai, Yau-Yau; Wang, Chun-Chieh; Wang, Jiun-Jie
Raised plasma soluble P-selectin in peripheral arterial occlusive disease enhances leukocyte adhesion.
Raised levels of soluble P-selectin (sP-selectin) have been reported in the plasma of patients with vascular diseases; however, the functional importance of this ligand remains unclear. In this study we have examined a potential role for plasma sP-selectin in regulating neutrophil adhesion in patients with peripheral arterial occlusive disease (PAOD). Patients with PAOD had significantly higher levels of sP-selectin (mean+/-SD: 73.3+/-13.0 versus 16.7+/-6.4 ng/mL) and enhanced whole blood leukocyte adhesion to platelets under shear. To examine whether the raised sP-selectin levels can directly influence leukocyte adhesion, isolated neutrophils were incubated with plasma from PAOD patients before and after immunodepletion of sP-selectin. Neutrophil adhesion to fibrinogen increased 2-fold following incubation with PAOD plasma, which was abrogated on sP-selectin immunodepletion. We subsequently demonstrated that recombinant sP-selectin dose-dependently (75 to 250 ng/mL) increased leukocyte adhesion to fibrinogen and platelet monolayers. This increase was PSGL-1 and Src kinase-dependent and correlated with an increase in sP-selectin-mediated Mac-1 activation. sP-selectin-stimulated neutrophil adhesion to platelet monolayers was inversely correlated with shear, such that at low shear (50 s(-1)) a 92.7%+/-15.7 increase in adhesion was observed decreasing to 38.5%+/-11.9 at 150 s(-1) and 10.1%+/-7.4 at 300 s(-1). These studies suggest a potentially important role for sP-selectin in modulating neutrophil adhesion in patients with PAOD, particularly at sites of low shear, where it raises the possibility that raised plasma sP-selectin levels may enhance leukocyte recruitment to vascular injury and promote disease progression. PMID:16339486
Woollard, K J; Kling, D; Kulkarni, S; Dart, A M; Jackson, S; Chin-Dusting, J
Early and late response-to-injury in patients undergoing transradial coronary angiography: arterial remodeling in smokers
Objectives: To investigate the effect of smoking on vascular response to transradial coronary angiography (TCA). Background: Cigarette smoking is the most important modifiable cardiovascular risk factor associated with endothelial dysfunction. Methods: Radial artery flow-mediated vasodilation (RA-FMD), local stiffness (fractional diameter change), intima-media thickness (IMT), luminal and external arterial diameter were measured in 40 current smokers (CS) and former smokers (FS) at 6-14 months at the site of previous TCA and contralateral control artery. Vascular regenerative capacity was studied as chemotactic cell migration in vitro and ex vivo (n=10) and the time course of endothelial functional recovery following RA-FMD up to 72 h after TCA (n=10). Results: At 10 ± 3 months after TCA, subjects exhibited significant local stiffening and increased IMT as compared to the control arm. These late structural changes were significantly more pronounced in CS as compared to FS. IMT thickening correlated with packyears, number of daily cigarettes, and inversely with RA-FMD. Nitric oxide synthase (NOS)-dependent chemotaxis of CS' circulating angiogenic cells was impaired. Ex vivo incubation of endothelial cells with CS' plasma inhibited NOS-dependent endothelial wound closure and chemotaxis. In vivo, TCA acutely decreased RA-FMD. At 24 h, RA-FMD had recovered in FS but remained impaired at 24 h and only recovered at 48 h in CS. Conclusion: In active smokers, transradial coronary angiography is associated with delayed early recovery from transient endothelial dysfunction, decreased NOS-dependent vascular regeneration, and late arterial remodeling pointing towards potential harmful effects of transradial coronary angiography on vascular function in distinct subsets of patients.
Sansone, Roberto; Stegemann, Emilia; Ozaslan, Goksen; Schuler, Dominik; Lukosz, Margarete; Rodriguez-Mateos, Ana; Lauer, Thomas; Westenfeld, Ralf; Kelm, Malte; Heiss, Christian
Uterine artery blood flow characteristics assessed during oestrus and the early luteal phase of pregnant and non-pregnant bitches.
The aim of this study was to measure uterine artery blood velocity daily using Doppler ultrasonography in 10 young and 10 older clinically normal bitches throughout oestrus. Typical arterial waveforms identified in young bitches were characterised by a systolic peak and subsequent flow throughout diastole, whereas in older bitches, flow was sometimes absent in diastole. For 3 days immediately prior to ovulation, at the time of declining plasma oestrogen and increasing progesterone concentrations, resistance index (RI) increased, principally associated with decreased diastolic velocity; in some bitches there was absent late diastolic flow during this time. In older bitches, the waveform appearance was more variable, with absent late and early diastolic flow observed in some cases. Mean RI was higher throughout oestrus for older bitches compared with young bitches, although both groups had a similar 3-day duration increase before ovulation. Nine of the young bitches and five of the older bitches became pregnant; litter size was smaller for the older bitches. Non-pregnant bitches: (1) were significantly older; (2) had fewer waveforms with continuous diastolic flow 2 days before ovulation; (3) had lower end diastolic velocity, higher RI and fewer waveforms with continuous diastolic flow 2 days after ovulation, and (4) had lower plasma progesterone concentrations 5 days after ovulation. These are the first detailed observations of uterine artery blood velocity and waveform appearance throughout oestrus in bitches, and this is the first description of a link between impaired diastolic flow and reduced fertility. Assessment of uterine artery velocity could be useful to promote understanding of physiological mechanisms and could also become an important tool to assess potential infertility. PMID:23770397
Freeman, S L; Russo, M; England, G C W
The midterm outcome and MACE of robotically enhanced grafting of left anterior descending artery with left internal mammary artery
Background We assessed the midterm outcome and the incidence of major adverse cardiovascular events in UK's largest Da Vinci assisted robotic coronary revascularisation cohort. This study was set up at the Imperial College NHS Trust, St. Mary's Hospital, London, United Kingdom. Method Benchmarking approach through retrospective audit of the regional outcomes against standards in the published literature. Data was collected from the patient's records, communication with the primary care physicians and the national strategic tracing service. The results were compared with the published literature. Patients who underwent robotic assisted coronary revascularisation were included. Other robotic procedures or minimally invasive revascularisation without the use of the Da Vinci robot were excluded. The main outcome measure was the midterm survival up to five years and the incidence of major adverse cardiovascular events (MACE) up to three years. Results Since April 2002, one hundred consecutive patients underwent either off pump robotic assisted single vessel small thoracotomy (SVST, n?=?88), or off pump total endoscopic coronary artery bypass grafting (TCAB, n?=?12). All patients were operated on by the same primary surgeon but different assisting surgeons. All patients received a left internal mammary arterial (LIMA) graft as planned. The primary outcome of total one month and three years MACE and up to five year survival was 0, 9 and 96% respectively. Conclusions The procedural success rates in terms of morbidity and mortality up to five years are compatible to the outcomes observed outside the United Kingdom. These results are not inferior to that of conventional off pump single vessel coronary surgery or percutaneous coronary intervention to the LAD.
Early results of bilateral pulmonary artery banding for hypoplastic left heart syndrome
Objective: To compare the haemodynamics and perioperative course of initial palliation with bilateral pulmonary artery banding (PAB) and the Norwood procedure. Methods: Between April 2004 and December 2007, 43 consecutive children with hypoplastic left heart syndrome (HLHS) or a variant underwent initial palliation (PAB, n=18; Norwood, n=25). Clinical perioperative data were analysed. In the PAB group, lipo-prostaglandin E1 administration was
Takahisa Sakurai; Hideaki Kado; Toshihide Nakano; Kazuhiro Hinokiyama; Akira Shiose; Masaki Kajimoto; Kunihiko Joo; Yuichi Ueda
Early Endovascular Management of Oculomotor Nerve Palsy Associated with Posterior Communicating Artery Aneurysms
Summary Palsy of the third cranial nerve (oculomotor nerve, CNIII) is a well-known clinical presentation of posterior communicating artery (P-com) aneurysm. We report a series of 11 patients with partial or complete third nerve palsy secondary to P-com aneurysm. All were treated with endovascular embolization within seven days of symptom onset. Third nerve palsy symptoms resolved in 7/11 (64%), improved in 2/11 (18%) and did not change in 2/11 (18%) patients
Santillan, A.; Zink, W.E.; Knopman, J.; Riina, H.A.; Gobin, Y.P.
Splenic Artery Transposition Graft Usage for the Supply of the Right Hepatic Artery: A Case Report
Hepatic artery aneurysms are responsible for 12% to 20% of all visceral arterial aneurysms. Because most patients are asymptomatic, this disease is generally diagnosed incidentally during radiologic examination. Aneurysm rupture develops in 14% to 80% of cases, depending on the aneurysmatic segment's diameter and location, as well as other etiologic factors. Mortality rates associated with rupture range between 20% and 70%. Thus, early diagnosis and timely initiation of medical interventions are critical to improve survival rates. Here, we present a male patient, age 69 years, with a hepatic artery aneurysm that was detected incidentally. The 3-cm aneurysm was detected on contrast-enhanced computed tomography and extended from the common hepatic artery to the hepatic trifurcation. A laparotomy was performed using a right subcostal incision. After dissection of the hepatoduodenal ligament, the common, right, and left hepatic arteries, as well as the gastroduodenal artery, were suspended separately. Then, the aneurysmatic hepatic artery segment was resected, and the gastroduodenal artery stump was ligated. An end-to-end anastomosis was formed between the left and common hepatic arteries, followed by an end-to-end anastomosis formed between the right hepatic artery and splenic artery using a splenic artery transposition graft. Postoperative follow-up examinations showed that both hepatic arterial circulations were good, and no splenic infraction had developed.
Odabasi, Mehmet; Eris, Cengiz; Yildiz, Mehmet Kamil; Abuoglu, Hasan; Akbulut, Sami; Saglam, Abdullah
Maternal alcohol consumption in pregnancy enhances arterial stiffness and alters vasodilator function that varies between vascular beds in fetal sheep.
While the impact of alcohol consumption by pregnant women on fetal neurodevelopment has received much attention, the effects on the cardiovascular system are not well understood. We hypothesised that repeated exposure to alcohol (ethanol) in utero would alter fetal arterial reactivity and wall stiffness, key mechanisms leading to cardiovascular disease in adulthood. Ethanol (0.75 g (kg body weight)(-1)) was infused intravenously into ewes over 1 h daily for 39 days in late pregnancy (days 95-133 of pregnancy, term ?147 days). Maternal and fetal plasma ethanol concentrations at the end of the hour were ?115 mg dl(-1), and then declined to apparent zero over 8 h. At necropsy (day 134), fetal body weight and fetal brain-body weight ratio were not affected by alcohol infusion. Small arteries (250-300 ?m outside diameter) from coronary, renal, mesenteric, femoral (psoas) and cerebral beds were isolated. Endothelium-dependent vasodilatation sensitivity was reduced 10-fold in coronary resistance arteries, associated with a reduction in endothelial nitric oxide synthase mRNA (P = 0.008). Conversely, vasodilatation sensitivity was enhanced 10-fold in mesenteric and renal resistance arteries. Arterial stiffness was markedly increased (P = 0.0001) in all five vascular beds associated with an increase in elastic modulus and, in cerebral vessels, with an increase in collagen I? mRNA. Thus, we show for the first time that fetal arteries undergo marked and regionally variable adaptations as a consequence of repeated alcohol exposure. These alcohol-induced vascular effects occurred in the apparent absence of fetal physical abnormalities or fetal growth restriction. PMID:24756643
Parkington, Helena C; Kenna, Kelly R; Sozo, Foula; Coleman, Harold A; Bocking, Alan; Brien, James F; Harding, Richard; Walker, David W; Morley, Ruth; Tare, Marianne
Cyclic AMP selectively enhances bradykinin receptor synthesis and expression in cultured arterial smooth muscle. Inhibition of angiotensin II and vasopressin response.
Bradykinin receptors on vascular smooth muscle may play an important role in regulating the endogenous effects of the vascular kallikrein-kinin system. The present study examined the effect of cyclic nucleotides on bradykinin-stimulated responses in cultured arterial smooth muscle cells. Short term stimulation (1 min) with cyclic AMP produced a variable inhibition of bradykinin-stimulated calcium mobilization which was lost in later passaged cells. However, long-term stimulation (24 h) produced a consistent increase in bradykinin-stimulated calcium mobilization in both early and late passaged cells. Further analysis demonstrated that chronic exposure to cAMP produced a twofold increase in both the number of cell surface bradykinin receptors and in bradykinin-stimulated phosphoinositide hydrolysis. The increase in bradykinin receptors was time dependent (> 7 h) and blocked by protein synthesis inhibitors, suggesting that cAMP enhanced the synthesis of new bradykinin receptors. The increase in bradykinin receptor binding and calcium mobilization was also stimulated by cholera toxin, forskolin, and isobutylmethylxanthine, but not isoproterenol or prostaglandin E2. Of considerable interest, prolonged exposure to cAMP inhibited both angiotensin II and arginine vasopressin-stimulated phosphoinositide hydrolysis and intracellular calcium mobilization. In summary, prolonged treatment with cAMP selectively stimulates the synthesis and expression of bradykinin receptors on arterial smooth muscle while decreasing the responsiveness to vasoconstrictor agonists such as angiotensin II and vasopressin. Images
Dixon, B S
Dynamic contrast-enhanced magnetic resonance imaging in patients with pulmonary arterial hypertension
Abstract Dynamic contrast–enhanced (DCE) time-resolved magnetic resonance (MR) imaging is a technique whereby the passage of an intravenous contrast bolus can be tracked through the pulmonary vascular system. The aim of this study was to investigate the prognostic significance of DCE-MR pulmonary blood transit times in patients with pulmonary arterial hypertension (PAH). Seventy-nine patients diagnosed with PAH underwent pulmonary DCE imaging at 1.5 T using a time-resolved three-dimensional spoiled gradient echo sequence. The prognostic significance of two DCE parameters, full width at half maximum (FWHM) of the first-pass clearance curve and pulmonary transit time (PTT), along with demographic and invasive catheter measurements, was evaluated by univariate and bivariate Cox proportional hazards regression and Kaplan-Meier analysis. DCE-MR transit times were most closely correlated with cardiac index (CI) and pulmonary vascular resistance index (PVRI) and were both found to be accurate for detecting reduced CI (FWHM area under the curve [AUC] at receiver operating characteristic analysis = 0.91 and PTT AUC = 0.92, respectively) and for detecting elevated PVRI (FWHM AUC = 0.88 and PTT AUC = 0.84, respectively). During the follow-up period, 25 patients died. Patients with longer measurements of FWHM (P = 0.0014) and PTT (P = 0.004) were associated with poor outcome at Kaplan-Meier analysis, and both parameters were strong predictors of adverse outcome from Cox proportional hazards analysis (P = 0.013 and 0.010, respectively). At bivariate analysis, DCE measurements predicted mortality independent of age, gender, and World Health Organization functional class; however, invasive hemodynamic indexes CI, PVRI, and DCE measurements were not independent of one another. In conclusion, DCE-MR transit times predict mortality in patients with PAH and are closely associated with clinical gold standards CI and PVRI.
Condliffe, Robin; Marshall, Helen; Elliot, Charlie; Kiely, David G.; Wild, Jim M.
Early Gaseous Oxygen Enrichment to Enhance Magnetite Pellet Oxidation
NASA Astrophysics Data System (ADS)
It is suggested that oxygen enrichment in the gas atmosphere, during continuous heating of magnetite pellets, can cause pellets to be oxidized throughout their volumes, eliminating unoxidized cores. The peculiarities of the oxidation kinetics of magnetite concentrate imply that such oxygen enrichment might be particularly effective at lower temperatures. This suggestion was tested by developing and testing a mixed-control model for pellet oxidation (to allow the sizes of unreacted cores to be predicted), and by experimentally testing the effects of oxygen enrichment at relatively low temperatures ("early oxygen enrichment"). The results confirmed that the extents (depth) of oxidation and pellet strength were both improved significantly by applying oxygen enrichment up to 873 K (600 °C), as part of a heating cycle up to 1073 K (800 °C).
Tang, Ming; Cho, Hyeon Jeong; Pistorius, Petrus Christiaan
Lipopolysaccharide induces H1 receptor expression and enhances histamine responsiveness in human coronary artery endothelial cells.
Summary Histamine is a well-recognized modulator of vascular inflammation. We have shown that histamine, acting via H1 receptors (H1R), synergizes lipopolysaccharide (LPS)-induced production of prostaglandin I(2) (PGI(2)), PGE(2) and interleukin-6 (IL-6) by endothelial cells. The synergy between histamine and LPS was partly attributed to histamine -induced expression of Toll-like receptor 4 (TLR4). In this study, we examined whether LPS stimulates the H1R expression in human coronary artery endothelial cells (HCAEC) with resultant enhancement of histamine responsiveness. Incubation of HCAEC with LPS (10-1000 ng/ml) resulted in two-fold to fourfold increases in H1R mRNA expression in a time-dependent and concentration-dependent fashion. In contrast, LPS treatment did not affect H2R mRNA expression. The LPS-induced H1R mRNA expression peaked by 4 hr after LPS treatment and remained elevated above the basal level for 20-24 hr. Flow cytometric and Western blot analyses revealed increased expression of H1R protein in LPS-treated cells. The specific binding of [(3)H]pyrilamine to H1R in membrane proteins from LPS-treated HCAEC was threefold higher than the untreated cells. The LPS-induced H1R expression was mediated through TLR4 as gene silencing by TLR4-siRNA and treatment with a TLR4 antagonist inhibited the LPS effect. When HCAEC were pre-treated with LPS for 24 hr, washed and challenged with histamine, 17-, 10- and 15-fold increases in PGI(2), PGE(2) and IL-6 production, respectively, were noted. Histamine-induced enhancement of the synthesis of PGI(2), PGE(2) and IL-6 by LPS-primed HCAEC was completely blocked by an H1R antagonist. The results demonstrate that LPS, through TLR4 activation, up-regulates the expression and function of H1R and amplifies histamine-induced inflammatory responses in HCAEC. PMID:21255012
Raveendran, Vineesh V; Tan, Xiaoyu; Sweeney, Matthew E; Levant, Beth; Slusser, Joyce; Stechschulte, Daniel J; Dileepan, Kottarappat N
Resistance to Erythropoiesis-Stimulating Agents Is Associated with Arterial Microcalcification in Early Hemodialysis Patients
The aim of this study was to evaluate the relationship between arterial microcalcification (AMiC) and erythropoiesis-stimulating agents (ESA) hyporesponsiveness in hemodialysis patients. The presence of AMiC was confirmed by pathologic examination of von Kossa-stained arterial specimens acquired during vascular access surgery. We assessed the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram body weight divided by the hemoglobin level. AMiC was detected in 33 (40.2%) of 82 patients. Patients with diabetes had a higher incidence of AMiC than patients without diabetes. The serum levels of albumin and cholesterol were higher in patients without AMiC than in patients with AMiC. The serum levels of intact parathyroid hormone were lower in patients with AMiC than in patients without AMiC. The serum levels of phosphate and calcium-phosphorus product did not differ between the two groups. The mean EHRI value was higher in patients with AMiC than in patients without AMiC. In multivariate analyses, ESA hyporesponsiveness and diabetes showed a significant association with AMiC. In conclusion, ESA hyporesponsiveness may be a clinical relevant parameters related to AMiC in hemodialysis patients.
Won, Hye Sung; Choi, Su Jin; Yun, Yu Seon; Shin, Ok-Ran; Ko, Yoon Ho; Kim, Young Soo; Yoon, Sun Ae; Kim, Young Ok
Hydrophilic Polymers Enhance Early Functional Outcomes after Nerve Autografting
Background Approximately 12% of operations for traumatic neuropathy are for patients with segmental nerve loss and less than 50% of these injuries obtain meaningful functional recovery. Polyethylene glycol (PEG) therapy has been shown to improve functional outcomes after nerve severance and we hypothesized this therapy could also benefit nerve autografting. Methods A segmental rat sciatic nerve injury model was used, whereby a 0.5 cm defect was repaired with an autograft using microsurgery. Experimental animals were treated with solutions containing methylene blue (MB) and PEG; control animals did not receive PEG. Compound Actions Potentials (CAPs) were recorded before nerve transection, after solution therapy, and at 72 hours postoperatively. The animals underwent behavioral testing at 24 and 72 hours postoperatively. After sacrifice, nerves were fixed, sectioned, and immunostained to allow for quantitative morphometric analysis. Results The introduction of hydrophilic polymers greatly improved morphological and functional recovery of rat sciatic axons at 1–3 days following nerve autografting. PEG therapy restored CAPs in all animals and CAPs were still present 72 hours postoperatively. No CAPS were detectable in control animals. Footfall asymmetry scores and sciatic functional index scores were significantly improved for PEG therapy group at all time points (p <0.05 and p<0.001; p <0.001 and p <0.01). Sensory and motor axon counts were increased distally in nerves treated with PEG compared to control (p = 0.0189 and p = 0.0032). Conclusions PEG therapy improves early physiologic function, behavioral outcomes, and distal axonal density after nerve autografting.
Sexton, Kevin W.; Pollins, Alonda C.; Cardwell, Nancy L.; Del Corral, Gabriel A.; Bittner, George D.; Shack, R. Bruce; Nanney, Lillian B.; Thayer, Wesley P.
AIM After return of spontaneous circulation (ROSC) from cardiac arrest, profound myocardial stunning and systemic inflammation may cause hemodynamic alterations; however, the prevalence of post-ROSC hemodynamic instability and the strength of association with outcome have not been established. We tested the hypothesis that exposure to arterial hypotension after ROSC occurs commonly (>50%) and is an independent predictor of death. METHODS Single-center retrospective cohort study of all post-cardiac arrest patients over one year. Inclusion criteria: (1) age >17; (2) non-trauma; (3) sustained ROSC after cardiac arrest. Using the Jones criteria, subjects were assigned to one of two groups based on the presence of hypotension within 6 hours after ROSC: (1) Exposures – two or more systolic blood pressures (SBP) <100 mmHg or (2) Non-exposures – less than two SBP <100 mmHg. The primary outcome was in-hospital mortality. We compared mortality rates between groups and used multivariate logistic regression to determine if post-ROSC hypotension independently predicted death. RESULTS 102 subjects met inclusion criteria. In-hospital mortality was 75%. Exposure to hypotension occurred in 66/102 (65%) and was associated with significantly higher mortality (83%) compared to non-exposures (58%, p=0.01). In a model controlling for common confounding variables (age, pre-arrest functional status, arrest rhythm, and provision of therapeutic hypothermia), early exposure to hypotension was a strong independent predictor of death (OR 3.5 [95% CI 1.3–9.6]). CONCLUSIONS Early exposure to arterial hypotension after ROSC was common and an independent predictor of death. These data suggest that post-ROSC hypotension could potentially represent a therapeutic target in post-cardiac arrest care.
Kilgannon, J. Hope; Roberts, Brian W.; Reihl, Lisa R.; Chansky, Michael E.; Jones, Alan E.; Dellinger, R. Phillip; Parrillo, Joseph E.; Trzeciak, Stephen
Involvement of the genicular branches in cystic adventitial disease of the popliteal artery as a possible marker of unfavourable early clinical outcome: a case report
Introduction Cystic adventitial disease of the popliteal artery is a rare cause of non-atheromatous claudication. It usually requires surgery to improve the distance walked by patients. Case presentation We report the case of a 44-year-old Caucasian man with unilateral symptomatic popliteal cysts extending to his genicular branches and associated with multilevel stenosis of his anterior tibial artery. A surgical evacuation of the cysts successfully restored his arterial patency and led to an objective haemodynamic improvement but was associated with early recurrence of symptoms. Conclusion We suggest that the involvement of the genicular branches in cystic adventitial disease of the popliteal artery is a possible indicator of extensive adventitial degeneration and unfavourable clinical prognosis.
Semi-automatic segmentation and quantification of the internal carotid artery from 3D contrast-enhanced MR angiograms
NASA Astrophysics Data System (ADS)
A technique is presented for segmentation and quantification of stenosed internal carotid arteries in three-dimensional contrast-enhanced magnetic resonance angiography. Segmentation with sub-voxel accuracy of the internal carotid arteries (ICAs) has been achieved via level-set techniques in which the central axis serves as initialization. The central axis is determined with minmal user-interaction, viz. two user-defined points. Quantification is performed by measuring the cross-sectional area in the stenosis and at a reference segment in planes perpendicular to the central axis. The technique was applied to 52 ICAs. It is demonstrated that the method's reproducibility is better than the intra-observer agreement. Furthermore, the agreement between the presented method and the observers is better than the inter-observer agreement.
van Bemmel, Cornelis M.; Niessen, Wiro J.
Intense adrenal enhancement in patients with acute pancreatitis and early organ failure.
Intense adrenal enhancement has previously been reported in patients with hypovolemic and septic shock. The purpose of this study was to assess whether this computed tomography (CT) finding is also observed in patients presenting with severe acute pancreatitis and early organ failure. A retrospective analysis of a prospectively collected database was performed. Out of 38 consecutive patients with predicted severe acute pancreatitis, 3 patients showed intense bilateral adrenal enhancement on early CT. All patients had early multiple organ failure and subsequently died. In two cases, pathologic correlation was obtained. Intense adrenal enhancement may be a new prognostic indicator in patients with acute pancreatitis, particularly when organ failure is present at the time of CT examination. Further studies are necessary to confirm this observation. PMID:17594117
Bollen, T L; van Santvoort, H C; Besselink, M G H; van Ramshorst, B; van Es, H W; Gooszen, H G
Dual-mode microwave system to enhance early detection of cancer
NASA Technical Reports Server (NTRS)
A dual-mode microwave system has been developed that will permit early detection of cancer. The system combines the use of the passive microwave radiometer with an active transmitter. The active transmitter will provide localized heating to enhance early detection by taking advantage of the differential heating (i.e., tumor temperature with respect to surrounding tissue) associated with the thermal characteristics of tumors.
Carr, K. L.; El-Mahdi, A. M.; Shaeffer, J.
Regional Ischemia and Ischemic Injury in Patients With Acute Middle Cerebral Artery Stroke as Defined by Early Diffusion-Weighted and Perfusion-Weighted MRI
Background and Purpose—We sought to map early regional ischemia and infarction in patients with middle cerebral artery (MCA) stroke and compare them with final infarct size using advanced MRI techniques. MRI can now delineate very early infarction by diffusion-weighted imaging (DWI) and abnormal tissue perfusion by perfusion-weighted imaging (PWI). Methods—Seventeen patients seen within 12 hours of onset of MCA stroke
Guy Rordorf; Walter J. Koroshetz; William A. Copen; Steven C. Cramer; Pamela W. Schaefer; Ronald F. Budzik; Lee H. Schwamm; Ferdinando Buonanno; A. Gregory Sorensen; Gilberto Gonzalez
osteoprotegerin-deficient mice develop early onset osteoporosis and arterial calcification
Osteoprotegerin (OPG) is a secreted protein that inhibits osteoclast formation. In this study the physiological role of OPG is investigated by generating OPG-deficient mice. Adolescent and adult OPG?/? mice exhibit a decrease in total bone density characterized by severe trabecular and cortical bone porosity, marked thinning of the parietal bones of the skull, and a high incidence of fractures. These findings demonstrate that OPG is a critical regulator of postnatal bone mass. Unexpectedly, OPG-deficient mice also exhibit medial calcification of the aorta and renal arteries, suggesting that regulation of OPG, its signaling pathway, or its ligand(s) may play a role in the long observed association between osteoporosis and vascular calcification.
Bucay, Nathan; Sarosi, Ildiko; Dunstan, Colin R.; Morony, Sean; Tarpley, John; Capparelli, Casey; Scully, Sheila; Tan, Hong Lin; Xu, Weilong; Lacey, David L.; Boyle, William J.; Simonet, W. Scott
Successful treatment of submucosal myoma with acute severe uterine hemorrhage by emergency uterine arterial embolization followed by early hysteroscopic myomectomy: a report of two cases
Two submucosal myoma cases with acute severe uterine hemorrhage were initially treated by emergency uterine arterial embolization for hemostasis. Then, after improvement of the general condition, early hysteroscopic myomectomy was performed. In one patient, complete resection was achieved. In another patient, the initial resection was incomplete because of the large tumor size. However, the remaining myoma tissue was spontaneously expelled
Akihiro Takeda; Shuichi Manabe; Satoyo Hosono; Hiromi Nakamura; Kayoko Kato; Kazuyuki Koyama
Preoperative detection of hepatocellular carcinoma: comparison of combined contrast-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography
The aim of this study was to compare Gd-DTPA-enhanced dynamic MR images, superparamagnetic iron oxide (SPIO)-enhanced MR images, combined Gd-DTPA-enhanced dynamic and SPIO-enhanced MR images, vs combined CT arterial portography (CTAP) and CT hepatic arteriography (CTHA), in the detection of hepatocellular carcinoma (HCC) using receiver operating characteristic (ROC) analysis. Twenty-four patients with 38 nodular HCCs (5–60 mm, mean 23.0 mm) were retrospectively
Hyo-Sung Kwak; Jeong-Min Lee; Chong-Soo Kim
Evaluation of cerebrovascular reserve using xenon-enhanced CT scanning in patients with symptomatic middle cerebral artery stenosis.
Cerebrovascular reserve (CVR) is an important prognostic factor in patients with major cerebral arterial steno-occlusive disease. However, few studies have examined CVR in symptomatic intracranial stenosis without ipsilateral extracranial internal carotid artery stenosis. This study sought to evaluate CVR in patients with symptomatic middle cerebral artery (MCA) stenosis using xenon-enhanced computed tomography (Xe/CT) with acetazolamide (ACZ) challenge. Twelve patients with symptomatic MCA stenosis were recruited. All patients were examined by Xe/CT to quantitatively measure resting cerebral blood flow (CBF) and received ACZ challenge to evaluate CVR. For resting CBF, no significant differences were found between the sides in four regions of interest. After the ACZ challenge test, the CVR was significantly different between hemispheres (ipsilateral versus contralateral CVR: 12.9 ± 24.3% versus 28.0 ± 16.8%, respectively; p=0.005) and in the MCA territory (ipsilateral versus contralateral CVR: 8.7 ± 24.7% versus 29.3 ± 24%, respectively; p=0.003). However, no significant differences in CVR were detected between cortical comparisons and white matter comparisons from the two sides. Thus, ACZ-challenge Xe/CT is useful for the measurement of CBF and CVR in these patients. Impaired CVR is an important characteristic of patients with symptomatic MCA stenosis. PMID:24238634
Cao, Wenjie; Cheng, Xin; Li, Haoxiong; Wang, Liang; Zhang, Xiaolong; Dong, Qiang
Early computed tomography features in extensive middle cerebral artery territory infarct: prediction of survival
Background: To assess the predictive value of prognosis of different computed tomography (CT) features and National Institutes of Health Stroke Scale score (NIHSS) in acute extensive middle cerebral artery (MCA) infarct. Methods: Fifty five patients with acute extensive MCA infarct had the CT performed within 24 hours of the onset of symptoms. A total of 11 CT features were analysed. The age distribution, presence of risk factors, presence of individual CT feature, the total CT score, and the NIHSS were correlated with the 30 day mortality. Results: Single explanatory variable analysis showed NIHSS, presence of midline shift, midline shift of more than 1 cm, extent of infarct, presence of hydrocephalus, effacement of subarachnoid space/cella media, attenuation of corticomedullary differentiation, and total CT score were associated with the 30 day mortality. Both extent of infarct >67% and attenuation of corticomedullary differentiation gave a sensitivity and specificity of 93% and 95%, respectively, for the prediction of survival. Logistic regression analysis showed that the extent of infarct and NIHSS were the only independent predictors. Conclusions: CT features and admission NIHSS are important parameters for prediction of survival in extensive MCA infarct.
Lam, W; Leung, T; Chu, W; Yeung, D; Wong, L; Poon, W
Enhanced Visual Speech Perception in Individuals with Early-Onset Hearing Impairment
ERIC Educational Resources Information Center
Purpose: L. E. Bernstein, M. E. Demorest, and P. E. Tucker (2000) demonstrated enhanced speechreading accuracy in participants with early-onset hearing loss compared with hearing participants. Here, the authors test the generalization of Bernstein et al.'s (2000) result by testing 2 new large samples of participants. The authors also investigated…
Auer, Edward T., Jr.; Bernstein, Lynne E.
Obstructive apneas induce early activation of mesenchymal stem cells and enhancement of endothelial wound healing
BACKGROUND: The aim was to test the hypothesis that the blood serum of rats subjected to recurrent airway obstructions mimicking obstructive sleep apnea (OSA) induces early activation of bone marrow-derived mesenchymal stem cells (MSC) and enhancement of endothelial wound healing. METHODS: We studied 30 control rats and 30 rats subjected to recurrent obstructive apneas (60 per hour, lasting 15 s
Alba Carreras; Mauricio Rojas; Theodora Tsapikouni; Josep M Montserrat; Daniel Navajas; Ramon Farré
Feedback Seeking in Early Adolescence: Self-Enhancement or Self-Verification?
ERIC Educational Resources Information Center
The authors examined whether early adolescents ("N" = 90) solicit self-enhancing feedback (i.e., positive feedback) or self-verifying feedback (i.e., feedback congruent with self-views, even when these views are negative). Sixth, seventh, and eighth graders first completed a self-perception measure and then selected whether to receive…
Rosen, Lisa H.; Principe, Connor P.; Langlois, Judith H.
Early Troponin T and Prediction of Potentially Correctable In-Hospital Complications after Coronary Artery Bypass Grafting Surgery
Background Peak levels of troponin T (TnT) reliably predict morbidity and mortality after cardiac surgery. However, the therapeutic window to manage CABG-related in-hospital complications may close before the peak is reached. We investigated whether early TnT levels correlate as well with complications after coronary artery bypass grafting (CABG) surgery. Methods A 12 month consecutive series of patients undergoing elective isolated CABG procedures (mini-extra-corporeal circuit, Cardioplegic arrest) was analyzed. Logistic regression modeling was used to investigate whether TnT levels 6 to 8 hours after surgery were independently associated with in-hospital complications (either post-operative myocardial infarction, stroke, new-onset renal insufficiency, intensive care unit (ICU) readmission, prolonged ICU stay (>48 hours), prolonged need for vasopressors (>24 hours), resuscitation or death). Results A total of 290 patients, including 36 patients with complications, was analyzed. Early TnT levels (odds ratio (OR): 6.8, 95% confidence interval (CI): 2.2-21.4, P=.001), logistic EuroSCORE (OR: 1.2, 95%CI: 1.0-1.3, P=.007) and the need for vasopressors during the first 6 postoperative hours (OR: 2.7, 95%CI: 1.0-7.1, P=.05) were independently associated with the risk of complications. With consideration of vasopressor use during the first 6 postoperative hours, the sum of specificity (0.958) and sensitivity (0.417) of TnT for subsequent complications was highest at a TnT cut-off value of 0.8 ng/mL. Conclusion Early TnT levels may be useful to guide ICU management of CABG patients. They predict clinically relevant complications within a potential therapeutic window, particularly in patients requiring vasopressors during the first postoperative hours, although with only moderate sensitivity.
Gober, Volkhard; Hohl, Andreas; Gahl, Brigitta; Dick, Florian; Eigenmann, Verena; Carrel, Thierry P.; Tevaearai, Hendrik T.
Intracardiac repair of dextro-transposition of the great arteries in the newborn period. Early and late results.
Between November, 1978, and December, 1981, nine neonates with dextro-transposition of the great arteries (d-TGA) and intact ventricular septum underwent primary intracardiac repair (i.e., because of persistent hypoxemia following balloon atrial septostomy arterial Po2 between 17 and 27 mm Hg). Age and weight at operation ranged from 2 to 21 days (mean 6.7) and from 1,900 to 4,500 gm (mean 3,493), respectively. The Mustard procedure was used in the first three patients and the Senning technique in the last six. All operations were done with deep hypothermia and circulatory arrest lasting 43 to 88 minutes (mean 70). An associated patent ductus arteriosus was ligated in eight of the nine patients. There were no deaths. The patients have been followed up for an average of 23 months (range 1 to 36). All are asymptomatic and require no medication. In one patient, atrioventricular dissociation necessitated implantation of a pacemaker 2 weeks after operation. All others are in sinus rhythm with normal atrioventricular conduction. Hemodynamic and angiographic follow-up was obtained in seven patients 8 to 25 months postoperatively (average 14.5). Left ventricular pressure was less than 30 mm Hg and aortic oxygen saturation was greater than 90% in all patients. One of the patients who had the Mustard procedure had complete obstruction at the junction of the inferior vena cava and the lower limb of the baffle. No evidence of systemic venous obstruction was found in the patients who had the Senning procedure. Early primary intracardiac repair appears to be a satisfactory alternative in the treatment of neonates with persistent hypoxemia following balloon atrial septostomy. PMID:6827844
Fortune, R L; Paquet, M; Collins-Nakai, R L; Duncan, N F
Review of Source Images is Necessary for the Evaluation of Gadolinium-Enhanced MR Angiography for Renal Artery Stenosis
The purpose of this study was to assess interobserver variability and accuracy in the evaluation of renal artery stenosis (RAS) with gadolinium-enhanced MR angiography (MRA) and digital subtraction angiography (DSA) in patients with hypertension. The authors found that source images are more accurate than maximum intensity projection (MIP) for depicting renal artery stenosis. Two independent radiologists reviewed MRA and DSA from 38 patients with hypertension. Studies were postprocessed to display images in MIP and source images. DSA was the standard for comparison in each patient. For each main renal artery, percentage stenosis was estimated for any stenosis detected by the two radiologists. To calculate sensitivity, specificity and accuracy, MRA studies and stenoses were categorized as normal, mild (1-39%), moderate (40-69%) or severe ({>=}70%), or occluded. DSA stenosis estimates of 70% or greater were considered hemodynamically significant. Analysis of variance demonstrated that MIP estimates of stenosis were greater than source image estimates for both readers. Differences in estimates for MIP versus DSA reached significance in one reader. The interobserver variance for MIP, source images and DSA was excellent (0.80< {kappa}{<=} 0.90). The specificity of source images was high (97%) but less for MIP (87%); average accuracy was 92% for MIP and 98% for source images. In this study, source images are significantly more accurate than MIP images in one reader with a similar trend was observed in the second reader. The interobserver variability was excellent. When renal artery stenosis is a consideration, high accuracy can only be obtained when source images are examined.
Wehrschuetz, M., E-mail: firstname.lastname@example.com; Aschauer, M.; Portugaller, H.; Stix, A. [University Hospital Graz, Department of Radiology (Austria); Wehrschuetz-Sigl, E. [University Hospital Graz, Department of Angiology (Austria); Hausegger, K.; Ebner, F. [University Hospital Graz, Department of Radiology (Austria)
Left ventricular filling and early diastolic function at rest and during angina in patients with coronary artery disease.
Left ventricular diastolic function was studied in 11 patients with coronary artery disease. Single plane ventriculography (30 degrees right anterior oblique projection) was performed at rest and during an episode of angina immediately after a period of rapid atrial pacing. Left ventricular pressure was recorded simultaneously by a micromanometer tipped catheter. The ventriculograms were digitised frame by frame to derive continuous plots of left ventricular shape, volume, and rate of change of volume. The time constant (tau) of the fall in left ventricular pressure was determined from the exponential portion of pressure decay during isovolumic relaxation. Ventricular pressure-volume loops were constructed to study the left ventricular diastolic pressure-volume relation. The time of minimum left ventricular pressure was used to divide diastole into an early phase and a late phase. Angina was associated with an increase in end systolic volume and a fall in ejection fraction with no significant change in end diastolic volume. Peak left ventricular pressure was unchanged but left ventricular minimum and end diastolic pressures were both increased and the diastolic pressure-volume relation was moved upwards. The time constant of left ventricular pressure fall was prolonged. At rest more than 50% of the stroke volume entered the left ventricle during the period of early diastole. This proportion was significantly reduced during angina and as a consequence a significantly greater proportion of the stroke volume entered the ventricle during late diastole. Despite this, and although the left ventricular diastolic pressure-volume relation was moved upwards with angina, the mean slope of the relation during late diastole--that is, chamber stiffness--was not significantly altered. The upward shift of the left ventricular diastolic pressure-volume relation seen during angina is thus already apparent in early diastole, and its extent does not change during the later phase of diastole, which alone shows the property of passive stiffness. A primary increase in the passive stiffness of the ventricle cannot therefore be the cause of the upward shift of the diastolic pressure-volume relation, and events occurring in early diastole have to be looked to for an explanation. The study findings show that left ventricular function in early diastole is profoundly disturbed during angina pectoris and it is suggested that loss of elastic recoil and dissipation of this restoring force by asynchronous onset of relaxation and abnormal changes in shape are important factors contributing to this disturbance of function.
Dawson, J R; Gibson, D G
Early Postnatal EEG Features of Perinatal Arterial Ischaemic Stroke with Seizures
Background Stroke is the second most common cause of seizures in term neonates and is associated with abnormal long-term neurodevelopmental outcome in some cases. Objective To aid diagnosis earlier in the postnatal period, our aim was to describe the characteristic EEG patterns in term neonates with perinatal arterial ischaemic stroke (PAIS) seizures. Design Retrospective observational study. Patients Neonates >37 weeks born between 2003 and 2011 in two hospitals. Method Continuous multichannel video-EEG was used to analyze the background patterns and characteristics of seizures. Each EEG was assessed for continuity, symmetry, characteristic features and sleep cycling; morphology of electrographic seizures was also examined. Each seizure was categorized as electrographic-only or electroclinical; the percentage of seizure events for each seizure type was also summarized. Results Nine neonates with PAIS seizures and EEG monitoring were identified. While EEG continuity was present in all cases, the background pattern showed suppression over the infarcted side; this was quite marked (>50% amplitude reduction) when the lesion was large. Characteristic unilateral bursts of theta activity with sharp or spike waves intermixed were seen in all cases. Sleep cycling was generally present but was more disturbed over the infarcted side. Seizures demonstrated a characteristic pattern; focal sharp waves/spike-polyspikes were seen at frequency of 1–2 Hz and phase reversal over the central region was common. Electrographic-only seizure events were more frequent compared to electroclinical seizure events (78 vs 22%). Conclusions Focal electrographic and electroclinical seizures with ipsilateral suppression of the background activity and focal sharp waves are strong indicators of PAIS. Approximately 80% of seizure events were the result of clinically unsuspected seizures in neonates with PAIS. Prolonged and continuous multichannel video-EEG monitoring is advocated for adequate seizure surveillance.
Low, Evonne; Mathieson, Sean R.; Stevenson, Nathan J.; Livingstone, Vicki; Ryan, C. Anthony; Bogue, Conor O.; Rennie, Janet M.; Boylan, Geraldine B.
bFGF enhances the development of the collateral circulation after acute arterial occlusion.
An adequate collateral circulation is crucial to tissue survival subsequent to proximal major arterial occlusion. The precise mechanism of collateral blood vessel development and the biochemical mediators involved in this process are unknown. To evaluate the influence of a number of agents on the development of the collateral circulation, we developed a rat model of severe hind limb ischaemia. The recovery of blood flow after acute arterial occlusion was increased by exogenous basic fibroblast growth factor and heparin, and decreased by protamine. Erucamide (cis-13-docosenamide), an angiogenic lipid, had no effect on collateral blood flow. These results indicate that basic fibroblast growth factor and heparin are potential therapeutic agents in the treatment of peripheral vascular disease. PMID:1376988
Chleboun, J O; Martins, R N; Mitchell, C A; Chirila, T V
Tetrahydrobiopterin Supplementation Enhances Carotid Artery Compliance in Healthy Older Men: A Pilot Study
Background We performed a pilot study to test the hypothesis that acute oral ingestion of tetrahydrobiopterin (BH4), a key cofactor modulating vascular nitric oxide (NO) synthase activity, improves large elastic artery stiffness with aging in men. Methods Healthy older (63 ± 2 years; n = 8) and young (age 25 ± 1 years; n = 6) men were studied 3 h after ingestion of BH4 (10 mg·kg?1 body weight) or placebo on separate days in a randomized, placebo-controlled, double-blind study. Results Baseline carotid artery compliance was 37% lower (0.17 ± 0.02 vs. 0.22 ± 0.02 mm/mm Hg·10?1) and ?-stiffness was 42% higher (7.3 ± 1.1 vs. 4.2 ± 0.5 AU) in the older men (both P < 0.05). BH4 ingestion markedly increased circulating BH4 concentrations in both groups (17–19-fold, P < 0.05), but increased compliance (+39% to 0.23 ± 0.02 mm/mm Hg.10?1, P < 0.01) and decreased ?-stiffness index (–27% to 5.3 ± 0.7 AU, P < 0.01) only in the older men. BH4 also reduced carotid systolic blood pressure (SBP) in the older men (P < 0.05). Conclusions These preliminary results support the possibility that limited BH4 bioavailability contributes to impaired carotid artery compliance in healthy older men. Further studies are needed to determine if increasing BH4 bioavailability though oral BH4 supplementation may have therapeutic efficacy for improving large elastic artery compliance and reducing central SBP with aging. American Journal of Hypertension, advance online publication 7 June 2012; doi:10.1038/ajh.2012.70
Pierce, Gary L.
Toward early diagnosis of arteriosclerotic diseases: collaborative detection of carotid artery calcifications by computer and dentists on dental panoramic radiographs
NASA Astrophysics Data System (ADS)
Several studies have reported the presence of carotid artery calcifications (CACs) on dental panoramic radiographs (DPRs) as a possible sign of arteriosclerotic diseases. However, CACs are not easily visible at the common window level for dental examinations, and dentists, in general, are not looking for CACs. Computerized detection of CACs may help dentists in referring patients with a risk of arteriosclerotic diseases to have a detailed examination at a medical clinic. Downside of our previous method was a relatively large number of false positives (FPs). In this study, we attempted to reduce FPs by including an additional feature and selecting effective features for the classifier. A hundred DPRs including 34 cases with calcifications were included. Initial candidates were detected by thresholding the output of top-hat operation. For each candidate, 10 features and a new feature characterizing the relative position of a CAC with reference to the lower mandible edge were determined. After the rule-based FP reduction, candidates were classified into CACs and FPs by a support vector machine. Based on the leave-one-out cross-validation evaluations, an average number of FPs was 3.1 per image at 90.4% sensitivity using seven features selected. Compared to our previous method, the number of FPs was reduced by 38% at the same sensitivity level. The proposed method has a potential in identifying patients with a risk of arteriosclerosis early via general dental examinations.
Muramatsu, Chisako; Takahashi, Ryo; Hara, Takeshi; Hayashi, Tatsuro; Katsumata, Akitoshi; Zhou, Xiangrong; Fujita, Hiroshi
Dynamic Contrast-Enhanced MRI Assessment of Hyperemic Fractional Microvascular Blood Plasma Volume in Peripheral Arterial Disease: Initial Findings
Objectives The aim of the current study was to describe a method that assesses the hyperemic microvascular blood plasma volume of the calf musculature. The reversibly albumin binding contrast agent gadofosveset was used in dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) to assess the microvascular status in patients with peripheral arterial disease (PAD) and healthy controls. In addition, the reproducibility of this method in healthy controls was determined. Materials and Methods Ten PAD patients with intermittent claudication and 10 healthy control subjects were included. Patients underwent contrast-enhanced MR angiography of the peripheral arteries, followed by one DCE MRI examination of the musculature of the calf. Healthy control subjects were examined twice on different days to determine normative values and the interreader and interscan reproducibility of the technique. The MRI protocol comprised dynamic imaging of contrast agent wash-in under reactive hyperemia conditions of the calf musculature. Using pharmacokinetic modeling the hyperemic fractional microvascular blood plasma volume (Vp, unit: %) of the anterior tibial, gastrocnemius and soleus muscles was calculated. Results Vp was significantly lower for all muscle groups in PAD patients (4.3±1.6%, 5.0±3.3% and 6.1±3.6% for anterior tibial, gastrocnemius and soleus muscles, respectively) compared to healthy control subjects (9.1±2.0%, 8.9±1.9% and 9.3±2.1%). Differences in Vp between muscle groups were not significant. The coefficient of variation of Vp varied from 10–14% and 11–16% at interscan and interreader level, respectively. Conclusions Using DCE MRI after contrast-enhanced MR angiography with gadofosveset enables reproducible assessment of hyperemic fractional microvascular blood plasma volume of the calf musculature. Vp was lower in PAD patients than in healthy controls, which reflects a promising functional (hemodynamic) biomarker for the microvascular impairment of macrovascular lesions.
Versluis, Bas; Dremmen, Marjolein H. G.; Nelemans, Patty J.; Wildberger, Joachim E.; Schurink, Geert-Willem; Leiner, Tim; Backes, Walter H.
Polycomb binding precedes early-life stress responsive DNA methylation at the Avp enhancer.
Early-life stress (ELS) in mice causes sustained hypomethylation at the downstream Avp enhancer, subsequent overexpression of hypothalamic Avp and increased stress responsivity. The sequence of events leading to Avp enhancer methylation is presently unknown. Here, we used an embryonic stem cell-derived model of hypothalamic-like differentiation together with in vivo experiments to show that binding of polycomb complexes (PcG) preceded the emergence of ELS-responsive DNA methylation and correlated with gene silencing. At the same time, PcG occupancy associated with the presence of Tet proteins preventing DNA methylation. Early hypothalamic-like differentiation triggered PcG eviction, DNA-methyltransferase recruitment and enhancer methylation. Concurrently, binding of the Methyl-CpG-binding and repressor protein MeCP2 increased at the enhancer although Avp expression during later stages of differentiation and the perinatal period continued to increase. Overall, we provide evidence of a new role of PcG proteins in priming ELS-responsive DNA methylation at the Avp enhancer prior to epigenetic programming consistent with the idea that PcG proteins are part of a flexible silencing system during neuronal development. PMID:24599304
Murgatroyd, Chris; Spengler, Dietmar
eNOS Affects Both Early and Late Collateral Arterial Adaptation and Blood Flow Recovery After Induction of Hindlimb Ischemia in Mice
Objective The goals of this study were to determine if endothelial nitric oxide synthase (eNOS) affects both early and late collateral arterial adaptation and blood flow recovery after severe limb ischemia, and to determine if eNOS-derived NO was necessary for recruitment of CXCR4+ VEGFR1+ hemangiocytes to the site of ischemia. Methods and Results Two studies were carried out. In the first study, hindlimb ischemia was induced by unilateral femoral artery excision in 3 groups: C57Bl6 (wild type), eNOS-/-, and C57Bl/6 mice treated with L-NAME from 1 day prior to excision through day 3 after excision (early L-NAME group). These 3 groups were studied on the 3rd day after induction of ischemia. In the second study, hindlimb ischemia was induced in 2 groups: C57Bl/6 mice (wild type) and C57Bl/6 mice treated with L-NAME from the 3rd through the 28th day after induction of ischemia. These 2 groups were studied on the 28th day after induction of ischemia. Dependent variables included hindlimb perfusion, collateral artery diameter, and the number and location of hemangiocytes within the ischemic hindlimb. Results In the first study, the eNOS-/- and early L-NAME treatment groups developed toe gangrene by the 2nd day of ischemia. These groups demonstrated less blood flow recovery and smaller collateral artery diameter than the wild type group. Hemangiocytes were present within the adventitia of collateral arteries in the wild type group, but were only sparsely present, in a random pattern, in the eNOS-/- and early L-NAME treatment groups. In the second study, the late L-NAME group showed less blood flow recovery and smaller collateral artery diameter on the 28th day of ischemia than the wild type group. Hemangiocytes were present in a peri-capillary distribution in the wild type group, but present only sparsely in the late L-NAME treatment group. Conclusion eNOS-derived NO is necessary for both the early (day 3) and late (day 28) adaptive responses to hindlimb ischemia. NO is necessary for normal hemangiocyte recruitment to the ischemic tissue.
Park, Brian; Hoffman, Ari; Yang, Yagai; Yan, Jinglian; Tie, Guodong; Bagshahi, Hossein; Nowicki, Philip T.; Messina, Louis M.
Treatment of acute cerebral artery occlusion using the penumbra system: our early experience.
Intravenous recombinant tissue-type plasminogen activator (rt-PA) therapy is highly recommended to patients who are diagnosed with ischemic stroke within 4.5 hours after the onset while mechanical clot retrieval can be attempted in patients who are not indicated for or cannot effectively receive intravenous rt-PA therapy. In this article, we report early treatment outcomes and discuss the usefulness of mechanical clot retrieval using the Penumbra system (Penumbra Inc., Alameda, California, USA), especially in terms of technical cautions during the procedure and adaptability to elderly and high National Institutes of Health Stroke Scale (NIHSS) patients. We included 7 patients with thromboembolic occlusion. Pretreatment NIHSS score ranged from 11 to 36 (mean: 24.9). All patients achieved good recanalization [thrombolysis in cerebral infarction (TICI) grade 2a or greater] without complications. The NIHSS score at 30 days after the treatment ranged between 0 and 28 (mean: 12.4), and improved more than 10 points in 4 of the 7 patients (57.1%). To obtain good recanalization without complications, selection of suitable reperfusion catheter and careful manipulation of separator prefiguring the occluded distal vessels are essential. The improved NIHSS score at 30 days after the treatment may have led to favorable results, such as an increased participation in available rehabilitation programs and the alleviation of the burden of care. Our findings suggest that the Penumbra system might be effective for treatment in elderly patients or patients with high NIHSS score wherein rt-PA therapy is inadvisable or ineffective in ischemic stroke secondary to large vessel occlusion. Recanalization can improve their quality of life on condition that the procedure is performed successfully without serious complications. PMID:24759097
Shindo, Atsushi; Kawanishi, Masahiko; Kawakita, Kenya; Okauchi, Masanobu; Kawai, Nobuyuki; Hayashi, Naoki; Osaka, Naohiro; Tamiya, Takashi
Evidence of the early stage of porphyrin aggregation by enhanced Raman scattering and fluorescence spectroscopy
NASA Astrophysics Data System (ADS)
The early stage of fractal porphyrin diffusion-limited aggregation (DLA), induced by addition of a polyamine, is observed in aqueous solution by enhanced Raman scattering and fluorescence quenching. The enhancement of Raman scattering is due to nonlinear optical properties typical of fractal composites. Although this early stage (reaction-limited aggregation) has been theoretically predicted (by mean-field theory and molecular dynamics simulation), it is experimentally difficult to observe. During this initial stage, fluorescence quenching gives direct information on the decrease of the concentration of monomeric porphyrins, whereas Raman scattering (through characteristic vibrational modes of the aggregate) reports on the concentration of porphyrins in the aggregated form. These small clusters constitute the seeds for the DLA aggregation process leading to micrometric-sized fractals.
Micali, Norberto; Villari, Valentina; Romeo, Andrea; Castriciano, Maria Angela; Scolaro, Luigi Monsů
Experimental peripheral arterial disease: new insights into muscle glucose uptake, macrophage, and T-cell polarization during early and late stages.
Peripheral arterial disease (PAD) is a common disease with increasing prevalence, presenting with impaired walking ability affecting patient's quality of life. PAD epidemiology is known, however, mechanisms underlying functional muscle impairment remain unclear. Using a mouse PAD model, aim of this study was to assess muscle adaptive responses during early (1 week) and late (5 weeks) disease stages. Unilateral hindlimb ischemia was induced in ApoE(-/-) mice by iliac artery ligation. Ischemic limb perfusion and oxygenation (Laser Doppler imaging, transcutaneous oxygen pressure assessments) significantly decreased during early and late stage compared to pre-ischemia, however, values were significantly higher during late versus early phase. Number of arterioles and arteriogenesis-linked gene expression increased at later stage. Walking ability, evaluated by forced and voluntary walking tests, remained significantly decreased both at early and late phase without any significant improvement. Muscle glucose uptake ([18F]fluorodeoxyglucose positron emission tomography) significantly increased during early ischemia decreasing at later stage. Gene expression analysis showed significant shift in muscle M1/M2 macrophages and Th1/Th2 T cells balance toward pro-inflammatory phenotype during early ischemia; later, inflammatory state returned to neutrality. Muscular M1/M2 shift inhibition by a statin prevented impaired walking ability in early ischemia. High-energy phosphate metabolism remained unchanged (31-Phosphorus magnetic resonance spectroscopy). Results show that rapid transient muscular inflammation contributes to impaired walking capacity while increased glucose uptake may be a compensatory mechanisms preserving immediate limb viability during early ischemia in a mouse PAD model. With time, increased ischemic limb perfusion and oxygenation assure muscle viability although not sufficiently to improve walking impairment. Subsequent decreased muscle glucose uptake may partly contribute to chronic walking impairment. Early inflammation inhibition and/or late muscle glucose impairment prevention are promising strategies for PAD management. PMID:24744903
Pellegrin, Maxime; Bouzourčne, Karima; Poitry-Yamate, Carole; Mlynarik, Vladimir; Feihl, François; Aubert, Jean-François; Gruetter, Rolf; Mazzolai, Lucia
Human mast cells (HMC-1 5C6) enhance interleukin-6 production by quiescent and lipopolysaccharide-stimulated human coronary artery endothelial cells.
We examined the effect of intact human mast cells (HMC-1 5C6) and their selected mediators on interleukin-6 (IL-6) production and bone morphogenetic protein-2 (BMP-2) expression in human coronary artery endothelial cells (HCAEC) in the presence and absence of lipopolysaccharide (LPS). Scanning electron microscopy showed that HMC-1 5C6 cells adhere to HCAEC in cocultures. Addition of HMC-1 5C6 cells markedly enhanced the IL-6 production by quiescent and LPS-activated HCAEC even at the maximal concentration of LPS. Furthermore, mast cell-derived histamine and proteases accounted for the direct and synergistic effect of mast cells on IL-6 production that was completely blocked by the combination of histamine receptor-1 antagonist and protease inhibitors. Another novel finding is that histamine was able to induce BMP-2 expression in HCAEC. Collectively, our results suggest that endotoxin and mast cell products synergistically amplify vascular inflammation and that histamine participates in the early events of vascular calcification. PMID:22363102
Walia, Damandeep S; Sharma, Mukut; Raveendran, Vineesh V; Zhou, Jianping; Sharma, Ram; Stechschulte, Daniel J; Dileepan, Kottarappat N
Human Mast Cells (HMC-1 5C6) Enhance Interleukin-6 Production by Quiescent and Lipopolysaccharide-Stimulated Human Coronary Artery Endothelial Cells
We examined the effect of intact human mast cells (HMC-1 5C6) and their selected mediators on interleukin-6 (IL-6) production and bone morphogenetic protein-2 (BMP-2) expression in human coronary artery endothelial cells (HCAEC) in the presence and absence of lipopolysaccharide (LPS). Scanning electron microscopy showed that HMC-1 5C6 cells adhere to HCAEC in cocultures. Addition of HMC-1 5C6 cells markedly enhanced the IL-6 production by quiescent and LPS-activated HCAEC even at the maximal concentration of LPS. Furthermore, mast cell-derived histamine and proteases accounted for the direct and synergistic effect of mast cells on IL-6 production that was completely blocked by the combination of histamine receptor-1 antagonist and protease inhibitors. Another novel finding is that histamine was able to induce BMP-2 expression in HCAEC. Collectively, our results suggest that endotoxin and mast cell products synergistically amplify vascular inflammation and that histamine participates in the early events of vascular calcification.
Walia, Damandeep S.; Sharma, Mukut; Raveendran, Vineesh V.; Zhou, Jianping; Sharma, Ram; Stechschulte, Daniel J.; Dileepan, Kottarappat N.
Quantitative dynamic contrast-enhanced MRI for mouse models using automatic detection of the arterial input function.
Dynamic contrast-enhanced MRI (DCE-MRI) is widely accepted for the evaluation of cancer. DCE-MRI, a noninvasive measurement of microvessel permeability, blood volume and blood flow, is extremely useful for understanding disease mechanisms and monitoring therapeutic responses in preclinical research. For the accurate quantification of pharmacokinetic parameters using DCE-MRI, determination of the arterial input function (AIF) from a large arterial vessel near the tumor is required. However, a manual determination of AIF in mouse MR images is often difficult because of the small spatial dimensions or the location of the tumor. In this study, we propose an algorithm for the automatic detection of AIF from mouse DCE-MR images using Kendall's coefficient of concordance. The proposed method was tested with computer simulations and then applied to tumor-bearing mice (n = 8). Results from computer simulations showed that the proposed algorithm is capable of categorizing simulated AIF signals according to their noise levels. We found that the resulting pharmacokinetic parameters computed from our method were comparable with those from the manual determination of AIF, with acceptable differences in K(trans) (5.14 ± 3.60%), v(e) (6.02 ± 3.22%), v(p) (5.10 ± 7.05%) and k(ep) (5.38 ± 4.72%). The results of the current study suggest the usefulness of an automatically defined AIF using Kendall's coefficient of concordance for quantitative DCE-MRI in mouse models for cancer evaluation. PMID:21954069
Kim, Jae-Hun; Im, Geun Ho; Yang, Jehoon; Choi, Dongil; Lee, Won Jae; Lee, Jung Hee
Plasma F2-Isoprostanes and Coronary Artery Calcification: The CARDIA Study
Background: Oxidation of lipids in lipoproteins and cells may initiate and enhance the early development of cardiovascular disease. Method and Results: We assayed F2-isoprostanes, oxi- dation products of arachidonic acid, by gas chromatog- raphy-mass spectrometry in a biracial cohort of 2850 young healthy adult men and women. Coronary artery calcification (CAC), a component of coronary artery atherosclerosis, was detectable in
Myron Gross; Michael Steffes; David R. Jacobs; Xinhua Yu; Linda Lewis; Cora E. Lewis; Catherine M. Loria
Coronary artery remodeling in non-contrast CT images
NASA Astrophysics Data System (ADS)
A significant cause of coronary artery disease is the coronary atherosclerosis which leads to stenosis of coronary arteries. It has been shown in recent studies, using intravascular ultrasound and contrast-enhanced CT, that early atherosclerosis causes positive coronary artery remodeling, defined as increases in the cross-sectional area. It is hypothesized that detection of artery remodeling using non-contrast CT can be an important factor in sub-clinical assessment of cardiac risk for asymptomatic subjects. However, measuring remodeling in coronary arteries in non-contrast CT images is a challenging task because coronary arteries are small and the intensity of coronary arteries is similar to that of surrounding tissues. Automatic segmentation algorithms that have been successful in segmenting coronary arteries in contrast-enhanced images do not perform well. To overcome these difficulties, we developed an interactive application to enable effective measurement of coronary artery remodeling in non-contrast CT images. This application is an extension to the 3D Slicer image analysis platform. It allows users to visualize and trace the centerline of arteries in cross sectional views. The artery centerlines are displayed in a three dimensional view overlaid on the original image volume and color-coded according to the artery labels. Using this 3D artery model, the user can sample the cross-sectional area of the arteries at selected points for remodeling assessment. Initial validation has demonstrated the effectiveness of this method. A pilot study also showed positive correlation of large coronary artery remodeling with highest lifetime risks. Further evaluation is underway using larger study size and more measurement points.
Xu, Haiyong; Zheng, Mingna; Yang, Yanhua; Carr, J. Jeffery; Ge, Yaorong
Social paediatrics and early child development - the practical enhancements: Part 2
Parents have central and critical influence in the health, learning and development of their young children. The physician plays a key role in supporting this role of parents, and there are practical health interventions that practitioners can promote in everyday practice that are coherent with the population-based evidence related to childhood outcomes. Four child development enhancers are recognized – emotional awareness, reading books, appropriate discipline and preschool programs including appropriate play opportunities. The child's physician can give clear messages about why each enhancer is important and what parents can do to use them to create nurturing environments for their children. The present article provides the evidence for these interventions and a series of coordinated physician activities that will enhance the early learning opportunities of the first few years of life, for improved trajectories for health and well being.
Bertrand, Jane; Williams, Robin; Ford-Jones, Lee
Early and long term results of coronary artery bypass grafts in patients with dialysis dependant renal failure
Objective: Coronary artery disease is the main cause of mortality and morbidity in patients on renal therapy replacement. The aim of this study was to define peri-operative risk and long term results of coronary artery bypass grafts (CABG) in dialysis patients. Methods: this retrospective study included 82 patients in chronic dialysis who underwent CABG between 1978 and 1997. The mean
L. Labrousse; C. de Vincentiis; F. Madonna; C. Deville; X. Roques; E. Baudet
Enhanced contraction to noradrenaline, serotonin and nerve stimulation but normal endothelium-derived relaxing factor response in skin small arteries in human primary hypertension.
1. We measured the reactivity of 2 mm long ring segments of human resistance arteries dissected from gluteal skin biopsies and mounted on wires in a Mulvany-Halpern myograph for recording isometric force. Arteries were taken from eight normotensive (N) volunteers (average age 46 years, blood pressure 126/82 mmHg) and eight untreated hypertensives (H; average age 48 years, blood pressure 149/101 mmHg). 2. In small diameter arteries (internal diameter less than 500 microns), the cumulative concentration-response curves to noradrenaline, serotonin and angiotensin II had a greater maximum by 72, 300 and 69%, respectively, in vessels from hypertensive patients than in those from normal volunteers. Nerve stimulation also caused a greater maximum contraction in hypertensive vessels (by 352%). 3. Arteries from H and N patients contracted submaximally by the thromboxane mimetic U46619 were similarly sensitive to the endothelium-dependent relaxing factor (EDRF) acetylcholine, indicating no difference in EDRF release or sensitivity. 4. Morphological measurements of the ratio of wall thickness to lumen radius of the wire-mounted vessels showed no significant difference between H and N vessels. 5. In larger arteries (internal diameter greater than 500 microns), no response to acetylcholine was noted in either H or N arteries. The sensitivity to serotonin and angiotensin II was similar between these arteries but the EC50 to noradrenaline was less in H than in N arteries (delta EC50 = 0.61 -log mol/L). 6. Subcutaneous resistance arteries with an internal diameter less than 500 microns from hypertensive patients show enhanced contractility to noradrenaline, serotonin and nerve stimulation despite a lack of detectable medial hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1395116
Angus, J A; Jennings, G L; Sudhir, K
Operative and early results of coronary artery bypass grafting in female patients in different body mass indexes
Background Female gender has been reported to be an independent risk factor for coronary artery bypass grafting (CABG) in European System for Cardiac Risk Evaluation. The effect of the body size on the CABG outcome is less clear. There is ongoing debate about obesity as a risk factor for adverse outcomes after cardiovascular procedures. The goal of this retrospective study is to evaluate the in hospital and early postoperative outcomes in severe obese, obese and normal-slightly obese female patients after CABG. Methods In a four year period a total of 427 female patients underwent isolated CABG under cardiopulmonary bypass. The patients were allocated into three groups according to the Body Mass Index (BMI) as follows; group 1: severe obese patients; BMI > 35, group 2: obese patients; 30?BMI?35, group 3: normal-slightly obese patients; BMI < 30 Results The patients in group 3 were older than the group1 and group 2 (65,6 ± 8,3 year vs 63,01 ± 8,0 and 63,57 ± 8,4 year p < 0,05). In group 1 diabetic patients were more than in group 2 and group 3 respectively (54,4% vs 43,4% and 40%, p < 0,05). Urgent operation was more in group 1 than in group 2 and 3 respectively (37,6% vs 17,2% and 21,2% p < 0,05). The patients in group 3 had significantly greater postoperative drainage at 24 h compared with values in group 1 and group 2 (647 ± 142 ml vs. 539 ± 169 ml and 582 ± 133 ml, p < 0,05). Mortality rate in group 1 was 0,8%, 0% in group 2 and 1,2% in group 3 respectively. Wound problem has occured in 41 patients (9,6%).The percentage of postoperative wound problems was higher in group 1 but did not show statiscially difference. Following discharge a total of 43 (10,1%) patients re-hospitalized within 30 days. Re-hospitalization rate was 16,1% in group1, 9,8% in group 2 and 6,5% in group 3 (p < 0,05). Conclusion This study may give an aspect for evaluations of the inhospital-early mortality and morbidity after CABG in female patients in different BMI. Severe obesity is not a risk factor in-hospital mortality in female patients. However, severe obese female patients appear to have more wound problems and re-hospitalization rate after CABG compared to obese and normal-slightly obese patients.
Meta-analysis of effect of single versus dual antiplatelet therapy on early patency of bypass conduits after coronary artery bypass grafting.
Aspirin monotherapy represents a standard therapy for preserving patency after coronary artery bypass grafting. Randomized trials addressing whether dual antiplatelet therapy is superior to single antiplatelet therapy to achieve graft patency early after coronary surgery have shown inconsistent results. We performed a meta-analysis of randomized controlled trials comparing single versus dual antiplatelet therapy after coronary artery bypass grafting. In a systematic published works search, 5 randomized controlled trials meeting inclusion criteria were identified. Pooled efficacy and safety data were abstracted and analyzed using a fixed-effects model. The 5 trials included 958 patients and a total of 2,919 grafts with treatment up to 1 year after coronary bypass surgery. Early occlusion was identified in 165 (6.5%) of 2,526 bypass grafts. Early occlusion occurred in a greater proportion of grafts among patients treated with single therapy (105 of 1,369; 7.7%) compared with dual antiplatelet therapy (69 of 1,386; 5.0%; p = 0.005). The odds ratio for graft occlusion with single versus dual therapy was 1.59 (95% confidence interval 1.16 to 2.17). For vein grafts, single antiplatelet therapy was associated with a significantly increased graft loss rate (91 of 846; 10.8%) versus dual antiplatelet therapy (57 of 860; 6.6%; odds ratio 1.70 [1.20 to 2.40]; p = 0.003). There was no effect on arterial graft patency. Bleeding was noted in 3.3% and 4.9% of single and dual therapy treated patients, respectively, with only 3 trials reporting bleeding outcomes. In conclusion, among 958 patients randomly assigned to either single or dual antiplatelet therapy for up to 1 year after coronary bypass surgery, single antiplatelet therapy significantly increased the risk for graft occlusion, an effect isolated to vein grafts, not arterial grafts. PMID:24035160
Nocerino, Angelica G; Achenbach, Stephan; Taylor, Allen J
Early methylphenidate exposure enhances morphine antinociception and tolerance in adult rats.
Methylphenidate (MPH) is often used to reduce the symptoms of Attention-Deficit/Hyperactivity Disorder. Early MPH treatment in rats has been shown to enhance adult morphine-induced antinociception. Although this enhanced antinociception could improve pain treatment, it could also lead to enhanced tolerance to morphine. This hypothesis was tested by examining the effects of MPH administration during the pre-weanling period on morphine-induced antinociception and tolerance in adulthood. Male and female Sprague-Dawley rats received daily IP injections of saline or MPH (2 or 5 mg/kg) for 10 consecutive days beginning on post-natal day (PD) 11. At 60 days of age, morphine (0, 1.8, 3.2, 5.6, 10.0, and 18 mg/kg) antinociception was assessed. Beginning one day later, rats received two daily injections of either saline or morphine (5 mg/kg) for two consecutive days to induce tolerance. On PD 63 cumulative doses of morphine were administered as before to assess the development of tolerance. Rats pretreated with MPH showed enhanced acute morphine antinociception compared to saline pretreated controls. In addition, tolerance to morphine was greater in rats pretreated with MPH early in life. The magnitude of this decrease in morphine potency was dependent on the dose of MPH, such that animals that received 5 mg/kg of MPH from PD 11 to 20 showed the greatest tolerance. These findings demonstrate that MPH exposure during the pre-weanling period has long-lasting effects that include enhanced morphine antinociception and tolerance. PMID:19646456
Cyr, Michelle C; Morgan, Michael M
Pseudoaneurysm Formation Following Intrasphenoid Rupture of an Idiopathic Intracavernous Carotid Artery Aneurysm: Coil Migration and Early Recurrence after Endovascular Treatment
Summary Intrasphenoid rupture of a non-traumatic aneurysm of the cavernous carotid artery is rare. We describe a patient in whom this condition manifested with epistaxis and led to the formation of a pseudoaneurysm occupying the right sphenoid sinus. The lesion recurred after repeated attempts at conservative endovascular therapy. Eventually the patient was treated with endovascular occlusion of the right internal carotid artery. Our report emphasizes the relapsing behaviour of a non-traumatic aneurysm of the cavernous portion of the internal carotid artery ruptured into the sphenoid sinus.
De Blasi, R.; Bracciolini, E.; Chiumarulo, L.; Salvati, A.; Monetti, C.; Federico, F.; Carella, A.
Film coating of seeds with Bacillus cereus RS87 spores for early plant growth enhancement.
The plant growth-promoting rhizobacterium Bacillus cereus RS87 was previously reported to promote plant growth in various crops in both greenhouse and field trials. To apply as a plant growth promoting agent with practical use, it is essential to ease the burden of routine preparation of a fresh suspension of strain RS87 in laboratory. The objectives of this study were to investigate the feasibility of film-coating seeds with B. cereus RS87 spores for early plant growth enhancement and to reveal the indoleacetic acid (IAA) production released from strain RS87. The experiment consisted of the following 5 treatments: nontreated seeds, water-soaked seeds, film-coated seeds, seeds soaked with vegetative cells of strain RS87, and film-coated seeds with strain RS87 spores. Three experiments were conducted separately to assess seed emergence, root length, and plant height. Results showed that both vegetative cells and spores of strain RS87 significantly promoted (P < or = 0.05) seed emergence, root length and plant height over the control treatments. The strain RS87 also produced IAA. In conclusion, the film coating of seeds with spores of B. cereus RS87 demonstrated early plant growth enhancement as well as seeds using their vegetative cells. IAA released from strain RS87 would be one of the mechanisms for plant growth enhancement. PMID:18923555
Jetiyanon, Kanchalee; Wittaya-Areekul, Sakchai; Plianbangchang, Pinyupa
Pax7 is regulated by cMyb during early neural crest development through a novel enhancer.
The neural crest (NC) is a migratory population of cells unique to vertebrates that generates many diverse derivatives. NC cells arise during gastrulation at the neural plate border (NPB), which is later elevated as the neural folds (NFs) form and fuse in the dorsal region of the closed neural tube, from where NC cells emigrate. In chick embryos, Pax7 is an early marker, and necessary component of NC development. Unlike other early NPB markers, which are co-expressed in lateral ectoderm, medial neural plate or posterior-lateral mesoderm, Pax7 early expression seems more restricted to the NPB. However, the molecular mechanisms controlling early Pax7 expression remain poorly understood. Here, we identify a novel enhancer of Pax7 in avian embryos that replicates the expression of Pax7 associated with early NC development. Expression from this enhancer is found in early NPB, NFs and early emigrating NC, but unlike Pax7, which is also expressed in mesodermal derivatives, this enhancer is not active in somites. Further analysis demonstrates that cMyb is able to interact with this enhancer and modulates reporter and endogenous early Pax7 expression; thus, cMyb is identified as a novel regulator of Pax7 in early NC development. PMID:23942518
Vadasz, Stephanie; Marquez, Jonathan; Tulloch, Maria; Shylo, Natalia A; García-Castro, Martín I
Focused ultrasound (HIFU) induces localized enhancement of reporter gene expression in rabbit carotid artery
The development of accurate, safe, and efficient gene delivery remains a major challenge towards the realization of gene therapeutic prevention and treatment of cardiovascular diseases. In this study, we investigated the ability of high-intensity focused ultrasound (HIFU), a form of mechanical wave transmission, to act as a noninvasive tool for the enhancement of in vivo gene transfer into rabbit carotid
P E Huber; M J Mann; L G Melo; A Ehsan; D Kong; L Zhang; M Rezvani; P Peschke; F Jolesz; V J Dzau; K Hynynen
Contrast-enhanced cardiac MRI before coronary artery bypass surgery: impact of myocardial scar extent on bypass flow.
The aim of the study was to relate the extent of myocardial late gadolinium enhancement (LGE) in cardiac MRI to intraoperative graft flow in patients undergoing coronary artery bypass graft (CABG) surgery. Thirty-three CAD patients underwent LGE MRI before surgery using an inversion-recovery GRE sequence (turboFLASH). Intraoperative graft flow in Doppler ultrasonography was compared with the scar extent in each coronary vessel territory. One hundred and fourteen grafts were established supplying 86 of the 99 vessel territories. A significant negative correlation was found between scar extent and graft flow (r = -0.4, p < 0.0001). Flow in grafts to territories with no or small subendocardial scar was significantly higher than in grafts to territories with broad nontransmural or transmural scar (75 +/- 39 vs. 38 +/- 26 cc min(-1); p < 0.0001). In summary, the extent of myocardial scar as defined by contrast-enhanced MRI predicts coronary bypass graft flow. Beyond the probability of functional recovery, preoperative MRI might add value to surgery planning by predicting midterm bypass graft patency. PMID:18581115
Hunold, Peter; Massoudy, Parwis; Boehm, Claudia; Schlosser, Thomas; Nassenstein, Kai; Knipp, Stephan; Eggebrecht, Holger; Thielmann, Matthias; Erbel, Raimund; Jakob, Heinz; Barkhausen, Jörg
Enhanced sensitivity for detection of coronary artery disease by addition of atropine to dipyridamole echocardiography.
Dipyridamole echocardiography test (DET) has gained acceptance due to its safety, feasibility, diagnostic accuracy and prognostic power. The main limitation of the test is a less than ideal sensitivity in some patient subsets, such as those with limited coronary artery disease. Atropine with dipyridamole might theoretically combine to become a synergistic ischaemic stress test, by increasing myocardial oxygen demand through chronotropic stress and by reducing flow supply through a shortening of the diastolic interval under maximal coronary vasodilation. The aim of this study was to assess the effects of the addition of atropine to DET. Three hundred and twenty-one patients (age = 58 +/- 9 years), referred for testing in the echo lab, were initially studied by DET. Of these, 151 were stopped during or within the 2 min following dipyridamole infusion because of achievement of a predetermined end-point: obvious echocardiographic positivity (n = 137), severe chest pain (n = 3), diagnostic ST segment changes (n = 7) or limited side effects (n = 4). In another three cases, atropine was not given due to a history of glaucoma or severe prostatic hypertrophy. In the remaining 167 patients with a negative DET test, atropine (0.25 mg intravenously, repeated every min up to a maximum of 1 mg, if necessary) was added, starting 3 min after the end of the dipyridamole infusion. The dipyridamole-atropine echo test (DETA) was positive in 32 and negative in 135 patients, and no major side effects occurred in any patient.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8223736
Picano, E; Pingitore, A; Conti, U; Kozŕkovŕ, M; Boem, A; Cabani, E; Ciuti, M; Distante, A; L'Abbate, A
Hybrid Coronary Revascularization Using Limited Incisional Full Sternotomy Coronary Artery Bypass Surgery in Multivessel Disease: Early Results
Background There are several modalities of coronary artery revascularization for multivessel coronary artery disease. Hybrid coronary revascularization (HCR) with minimally invasive direct coronary artery bypass grafting was introduced for high-risk patients, and recently, many centers have been using it. Limited incisional full sternotomy coronary artery bypass (LIFCAB) involves left internal thoracic artery (LITA)-to-left anterior descending coronary artery (LAD) anastomosis through a sternotomy with a minimal skin incision; it could be considered another technique for minimally invasive LITA-to-LAD anastomosis. Our center has performed HCR using LIFCAB, and in this paper, we report our short-term results, obtained in the past 3 years. Methods The medical records of 38 patients from May 2010 to June 2013 were analyzed retrospectively. The observation period after HCR was 1 to 37 months (average, 18.3±10.3 months). The patency of revascularization was confirmed with postoperative coronary angio-computerized tomography or coronary angiography. Results There were 3 superficial wound complications, but no mortalities. All the LITA-to-LAD anastomoses were patent in the immediate postoperative and follow-up studies, but stenosis was detected in 3 cases of percutaneous coronary intervention. Conclusion HCR using LIFCAB is safe and yields satisfactory results from the viewpoint of revascularization for multivessel disease.
Kang, Joonkyu; Lee, Seok In; Moon, Mi Hyung; Kim, Hwan Wook; Jo, Gyun Hyun
Addendum to `numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system'
Two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system that is used for buried-object detection and environmental problems are presented. In the first model, the transmitting and receiving loop antennas accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with the fast Fourier transform (FFT) are utilized to investigate the scattering from buried conducting plates. In the second model, two magnetic dipoles are used to replace the transmitter and receiver. Both the theory and formulation are correct and the simulation results for the primary magnetic field and the reflected magnetic field are accurate.
Cui, T. J.; Chew, W. C.; Aydiner, A. A.; Wright, D. L.; Smith, D. V.; Abraham, J. D.
The response of the early developmental stages of Laminaria japonica to enhanced ultraviolet-B radiation
The responses of the early development of Laminaria japonica collected from Kiaochow Bay in China to enhanced ultraviolet-B radiation (UV-B, 280–320 nm) were studied in the laboratory.\\u000a The low UV-B radiations (11.7–23.4 J·m?2·d?1) had no significant effects on zoospores attachment, but when the UV-B dose > 35.1 J·m?2·d?1 the attachment decreased significantly compared with the control. Germination of embryospores was
Su Liu; QuanSheng Zhang; You Wang; Qing Ju; XueXi Tang
Sample preselection process designed to enhance early planning information. [Sampling program for evaluating nuclear weapon stockpiles
The DOE provides for the continuing evaluation of the nuclear weapon stockpiles through a stockpile sampling program in which randomly selected weapons are withdrawn for testing from the stockpiles each year. For some time, DOE has used a preselection scheme to obtain early identification of certain characteristics of the sample weapons for planning purposes, but which does so without jeopardizing the necessary randomization of sample selection. A DOD desire for additional and more detailed planning information to minimize weapon movements has led to an improvement of the original preselection scheme that enhances the planning information and its accuracy, while still preserving randomization.
Mueller, F.W.; Spencer, F.W.
Geometry and dimensions of the pulmonary artery bifurcation in children and adolescents: assessment in vivo by contrast-enhanced MR-angiography
We sought to establish normal values for the diameters of the main (MPA), right (RPA), and left (LPA) pulmonary arteries and\\u000a for the angles describing the geometry of the pulmonary artery bifurcation in children by using contrast-enhanced magnetic\\u000a resonance angiography (CE-MRA). CE-MRA was performed in 69 children without cardiovascular disease. The median age was 10 ± 4.9 years\\u000a (range 2–20), weight 37.4 ± 18.5 kg (10–82),
Zita Knobel; Christian J. Kellenberger; Thomas Kaiser; Manuela Albisetti; Eva Bergsträsser; Emanuela R. Valsangiacomo Buechel
Microglia Enhance Neurogenesis and Oligodendrogenesis in the Early Postnatal Subventricular Zone
Although microglia have long been considered as brain resident immune cells, increasing evidence suggests that they also have physiological roles in the development of the normal CNS. In this study, we found large numbers of activated microglia in the forebrain subventricular zone (SVZ) of the rat from P1 to P10. Pharmacological suppression of the activation, which produces a decrease in levels of a number of proinflammatory cytokines (i.e., IL-1?, IL-6, TNF-?, and IFN-?) significantly inhibited neurogenesis and oligodendrogenesis in the SVZ. In vitro neurosphere assays reproduced the enhancement of neurogenesis and oligodendrogenesis by activated microglia and showed that the cytokines revealed the effects complementarily. These results suggest that activated microglia accumulate in the early postnatal SVZ and that they enhance neurogenesis and oligodendrogenesis via released cytokines.
Shigemoto-Mogami, Yukari; Hoshikawa, Kazue; Goldman, James E.; Sekino, Yuko
On-pump beating-heart versus conventional coronary artery bypass grafting for revascularization in patients with severe left ventricular dysfunction: early outcomes
Background We sought to evaluate the effects of on-pump beating-heart versus conventional coronary artery bypass grafting techniques requiring cardioplegic arrest in patients with coronary artery disease with left ventricular dysfunction. Methods We report the early outcomes associated with survival, morbidity and improvement of left ventricular function in patients with low ejection fraction who underwent coronary artery bypass grafting between August 2009 and June 2012. Patients were separated into 2 groups: group I underwent conventional coronary artery bypass grafting and group II underwent an on-pump beating-heart technique without cardioplegic arrest. Results In all, 131 patients underwent coronary artery bypass grafting: 66 in group I and 65 in group II. Left ventricular ejection fraction was 26.6% ± 3.5% in group I and 27.7% ± 4.7% in group II. Left ventricular end diastolic diameter was 65.6 ± 3.6 mm in group I and 64.1 ± 3.2 mm in group II. There was a significant reduction in mortality in the conventional and on-pump beating-heart groups (p < 0.001). Perioperative myocardial infarction and low cardiac output syndrome were higher in group I than group II (both p < 0.05). Improvement of left ventricular function after the surgical procedure was better in group II than group I. Conclusion The on-pump beating-heart technique is the preferred method for myocardial revascularization in patients with left ventricular dysfunction. This technique may be an acceptable alternative to the conventional technique owing to lower postoperative mortality and morbidity.
Erkut, Bilgehan; Dag, Ozgur; Kaygin, Mehmet Ali; Senocak, Mutlu; Limandal, Husnu Kamil; Arslan, Umit; Kiymaz, Adem; Aydin, Ahmet; Kahraman, Nail; Calik, Eyup Serhat
Effects of Cognitive Enhancement Therapy on Employment Outcomes in Early Schizophrenia: Results from a 2-Year Randomized Trial
ERIC Educational Resources Information Center
Objective: To examine the effects of psychosocial cognitive rehabilitation on employment outcomes in a randomized controlled trial for individuals with early course schizophrenia. Method: Early course schizophrenia outpatients (N = 58) were randomly assigned to cognitive enhancement therapy (CET) or an enriched supportive therapy (EST) control and…
Eack, Shaun M.; Hogarty, Gerard E.; Greenwald, Deborah P.; Hogarty, Susan S.; Keshavan, Matcheri S.
Natural History of the Early Repolarization Pattern in a Biracial Cohort: CARDIA (Coronary Artery Risk Development in Young Adults) Study
Objectives The objective of this analysis was to determine the natural history and prospective association of cardiovascular risk factors with early repolarization (ER). Background ER is common and has been suggested to increase risk for cardiovascular mortality in middle-aged adults. Data are sparse regarding the natural history of ER from young adulthood to middle age. Methods We examined 5,069 participants (mean age 25 years at baseline; 40% black) from the CARDIA (Coronary Artery Risk Development in Young Adults) cohort over 20 years. Electrocardiograms were recorded at years 0 (Y0), 7 (Y7), and 20 (Y20) and coded as either definite, probable, possible, or no ER. Logistic regression was used to determine the association of cardiovascular risk factors with the presence of ER cross-sectionally and prospectively. Results A total of 941 of the 5,069 participants (18.6%) had definite ER at baseline, and only 119 of 2,505 participants (4.8%) at the Y20 examination still demonstrated the presence of ER. Younger age, black race, male sex, longer exercise duration and QRS duration, and lower body mass index (BMI), heart rate, QT index, and Cornell voltage were associated cross-sectionally with the presence of ER. Predictors of maintenance of ER from Y0 to Y20 were black race (odds ratio [OR]: 2.62; 95% CI; 1.61 to 4.25), BMI (OR: 0.62 per 1 SD; 95% CI: 0.40 to 0.94), serum triglyceride levels (OR: 0.66 per 1 SD; 95% CI: 0.45 to 0.98), and QRS duration (OR: 1.68 per 1 SD; 95% CI: 1.37 to 2.06) at baseline. Conclusions The prevalence of ER was significantly higher than previous estimates among asymptomatic young adults, and the majority of ER regressed by middle age. Black race, lower BMI, lower serum triglyceride levels, and longer QRS duration were independently associated with maintenance of ER over time.
Walsh, Joseph A.; Ilkhanoff, Leonard; Soliman, Elsayed Z.; Prineas, Ronald; Liu, Kiang; Ning, Hongyan; Lloyd-Jones, Donald M.
Pre-dawn stomatal opening does not substantially enhance early-morning photosynthesis in Helianthus annuus.
Most C3 plant species have partially open stomata during the night especially in the 3-5 h before dawn. This pre-dawn stomatal opening has been hypothesized to enhance early-morning photosynthesis (A) by reducing diffusion limitations to CO2 at dawn. We tested this hypothesis in cultivated Helianthus annuus using whole-shoot gas exchange, leaf level gas exchange and modelling approaches. One hour pre-dawn low-humidity treatments were used to reduce pre-dawn stomatal conductance (g). At the whole-shoot level, a difference of pre-dawn g (0.40 versus 0.17 mol m(-2) s(-1)) did not significantly affect A during the first hour after dawn. Shorter term effects were investigated with leaf level gas exchange measurements and a difference of pre-dawn g (0.10 versus 0.04 mol m(-2) s(-1)) affected g and A for only 5 min after dawn. The potential effects of a wider range of stomatal apertures were explored with an empirical model of the relationship between A and intercellular CO2 concentration during the half-hour after dawn. Modelling results demonstrated that even extremely low pre-dawn stomatal conductance values have only a minimal effect on early-morning A for a few minutes after dawn. Thus, we found no evidence that pre-dawn stomatal opening enhances A. PMID:24895756
Auchincloss, Lisa; Easlon, Hsien M; Levine, Diedre; Donovan, Lisa; Richards, James H
Prevention by insulin treatment of endothelial dysfunction but not enhanced noradrenaline-induced contractility in mesenteric resistance arteries from streptozotocin-induced diabetic rats.
1. Streptozotocin-induced diabetic rats (Wistar) were implanted with sustained release insulin pellets (release rate = 4 u day-1) or with placebo pellets (palmitic acid) from the onset of glycosuria. 2. Noradrenaline sensitivity, endothelium-dependent relaxation to acetylcholine and endothelium-independent relaxation to sodium nitroprusside were assessed in mesenteric resistance arteries from the insulin-treated (IT) diabetic animals and compared to placebo-implanted (PI) diabetics and age-matched controls. 3. Arteries from PI-diabetic rats (8-10 weeks) demonstrated an enhanced maximal response to noradrenaline compared to controls, which was not prevented by insulin treatment (control 2.65 +/- 0.17 mN mm-1, n = 18 arteries versus PI-diabetic 3.73 +/- 0.40 mM mm-1, n = 5, P < 0.05; control versus IT-diabetic 4.02 +/- 0.19 mN mm-1, n = 22, P < 0.001). Sensitivity to noradrenaline was similar between the three groups. 4. In the presence of the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME), IT and PI arteries were more sensitive to noradrenaline than control arteries (pEC50: control 5.75 +/- 0.08, n = 17, versus PI-diabetic 6.14 +/- 0.09, n = 8, P < 0.05; control versus IT-diabetic 6.38 +/- 0.08, n = 20, P < 0.001). 5. The maximum contractile response to depolarizing 125 mM K+ was significantly enhanced in IT-diabetic arteries but not PI-diabetic when compared to control arteries (maximum response: control 3.74 +/- 0.15 mN mm-1, n = 18, versus PI-diabetic 3.61 +/- 0.19 mN mm-1, n = 11, NS; control versus IT-diabetic 4.66 +/- 0.18 mN mm-1, n = 22, P < 0.001). 6. Endothelium-dependent relaxation to acetylcholine was profoundly impaired in the PI-diabetic arteries, but in the IT-diabetic arteries was not significantly different from controls (pEC50: control 7.64 +/- 0.19, n = 17, versus PI-diabetic 6.07 +/- 0.12, n = 8, P < 0.001; control versus IT-diabetic 7.36 +/- 0.09, n = 22, NS).(ABSTRACT TRUNCATED AT 250 WORDS)
Taylor, P. D.; Oon, B. B.; Thomas, C. R.; Poston, L.
Predicting the extent and location of coronary artery disease during the early postinfarction period by quantitative thallium-201 scintigraphy
The ability of quantitative thallium-201 scintigraphy to predict the extent and location of coronary artery disease before hospital discharge after acute myocardial infarction was evaluated in 52 patients. All patients underwent coronary angiography and serial thallium-201 imaging either at rest (10 patients) or after submaximal exercise stress (42 patients; target heart rate 120 beats/min). Two or three vessel disease was designated if abnormal thallium-201 uptake or washout patterns, or both, were seen in two or three vascular segments, respectively. Thus, 2 weeks after myocardial infarction, exercise thallium-201 scintigraphy is useful for predicting the extent and location of coronary artery disease, particularly stenoses in the left anterior descending and right coronary arteries. Moreover, thallium-201 imaging at rest is reliable in assessing the extent of coronary disease in hospitalized patients who cannot undergo exercise testing because of unstable angina, uncompensated heart failure, poorly controlled arrhythmias or physical limitations.
Gibson, R.S.; Taylor, G.J.; Watson, D.D.; Stebbins, P.T.; Martin, R.P.; Crampton, R.S.; Beller, G.A.
Routine Use of Three-Dimensional Contrast-Enhanced Moving-Table MR Angiography in Patients with Peripheral Arterial Occlusive Disease: Comparison with Selective Digital Subtraction Angiography
Purpose. To compare the diagnostic accuracy of contrast-enhanced (CE) three-dimensional (3D) moving-table magnetic resonance (MR) angiography with that of selective digital subtraction angiography (DSA) for routine clinical investigation in patients with peripheral arterial occlusive disease. Methods. Thirty-eight patients underwent CE 3D moving-table MR angiography of the pelvic and peripheral arteries. A commercially available large-field-of-view adapter and a dedicated peripheral vascular phased-array coil were used. MR angiograms were evaluated for grade of arterial stenosis, diagnostic quality, and presence of artifacts. MR imaging results for each patient were compared with those of selective DSA. Results. Two hundred and twenty-six arterial segments in 38 patients were evaluated by both selective DSA and MR angiography. No complications related to MR angiography were observed. There was agreement in stenosis classification in 204 (90.3%) segments; MR angiography overgraded 16 (7%) segments and undergraded 6 (2.7%) segments. Compared with selective DSA, MR angiography provided high sensitivity and specificity and excellent interobserver agreement for detection of severe stenosis (97% and 95%, {kappa} = 0.9 {+-} 0.03) and moderate stenosis (96.5% and 94.3%, {kappa} = 0.9 {+-} 0.03). Conclusion. Compared with selective DSA, moving-table MR angiography proved to be an accurate, noninvasive method for evaluation of peripheral arterial occlusive disease and may thus serve as an alternative to DSA in clinical routine.
Deutschmann, Hannes A.; Schoellnast, Helmut; Portugaller, Horst R. [University Hospital Graz, Medical University Graz, Department of Radiology (Austria); Preidler, Klaus W. [Diagnostikum Graz Sued-West (Austria); Reittner, Pia [University Hospital Graz, Medical University Graz, Department of Radiology (Austria); Tillich, Manfred [Diagnostikum Graz Sued-West (Austria); Pilger, Ernst [University Hospital Graz, Medical University Graz, Department of Angiology (Austria); Szolar, Dieter H. M. [Diagnostikum Graz Sued-West (Austria)], E-mail: firstname.lastname@example.com
Early failure of coronary artery bypass grafts: an albumin cross-linked glutaraldehyde (BioGlue) related complication.
Bioglue which constitutes albumin cross linked with glutaraldehyde (ACLG) produced by Cryolife, Inc, Kennesaw, GA was introduced as a better alternative to GRF glue with less tissue necrosis. We report a case of a 69-year-old male who developed stenosis of his saphenous vein and internal thoracic artery bypass grafts, requiring re-do coronary artery bypass grafting. Both fibrotic narrowing were in close proximity to the site of Bioglue application and appears to be a reaction to the glue. The advent of ACLG has facilitated surgery; however, this case highlights a potential side effect, emphasizing the judicious use of this hemostatic agent in patients.? PMID:21342262
Khan, Habib; Chaubey, Sanjay; Desai, Jatin
Detection of Coronary Artery Stenoses by Contrast-Enhanced, Retrospectively Electrocardiographically-Gated, Multislice Spiral Computed Tomography
Background—Multislice spiral computed tomography (MSCT) with retrospectively ECG-gated image reconstruction permits coronary artery visualization. We investigated the method's ability to identify high-grade coronary artery stenoses and occlusions. Methods and Results—A total of 64 consecutive patients were studied by MSCT (4 31 mm cross-sections, 500-ms rotation, table feed 1.5 mm\\/rotation, intravenous contrast agent, retrospectively ECG-gated image reconstruction). All coronary arteries and
Stephan Achenbach; Tom Giesler; Dieter Ropers; Stefan Ulzheimer; Hans Derlien; Christoph Schulte; Evelyn Wenkel; Werner Moshage; Werner Bautz; Werner G. Daniel; Willi A. Kalender; Ulrich Baum
Nonrigid motion compensation in B-mode and contrast enhanced ultrasound image sequences of the carotid artery
NASA Astrophysics Data System (ADS)
In this work, we investigate nonrigid motion compensation in simultaneously acquired (side-by-side) B-mode ultrasound (BMUS) and contrast enhanced ultrasound (CEUS) image sequences of the carotid artery. These images are acquired to study the presence of intraplaque neovascularization (IPN), which is a marker of plaque vulnerability. IPN quantification is visualized by performing the maximum intensity projection (MIP) on the CEUS image sequence over time. As carotid images contain considerable motion, accurate global nonrigid motion compensation (GNMC) is required prior to the MIP. Moreover, we demonstrate that an improved lumen and plaque differentiation can be obtained by averaging the motion compensated BMUS images over time. We propose to use a previously published 2D+t nonrigid registration method, which is based on minimization of pixel intensity variance over time, using a spatially and temporally smooth B-spline deformation model. The validation compares displacements of plaque points with manual trackings by 3 experts in 11 carotids. The average (+/- standard deviation) root mean square error (RMSE) was 99+/-74?m for longitudinal and 47+/-18?m for radial displacements. These results were comparable with the interobserver variability, and with results of a local rigid registration technique based on speckle tracking, which estimates motion in a single point, whereas our approach applies motion compensation to the entire image. In conclusion, we evaluated that the GNMC technique produces reliable results. Since this technique tracks global deformations, it can aid in the quantification of IPN and the delineation of lumen and plaque contours.
Carvalho, Diego D. B.; Akkus, Zeynettin; Bosch, Johan G.; van den Oord, Stijn C. H.; Niessen, Wiro J.; Klein, Stefan
Haploinsufficiency of insulin gene enhancer protein 1 (ISL1) is associated with d-transposition of the great arteries
Congenital heart defects are the most common malformation, and are the foremost causes of mortality in the first year of life. Among congenital heart defects, conotruncal defects represent about 20% and are severe malformations with significant morbidity. Insulin gene enhancer protein 1 (ISL1) has been considered a candidate gene for conotruncal heart defects based on its embryonic expression pattern and heart defects induced in Isl1 knockout mice. Nevertheless no mutation of ISL1 has been reported from any human subject with a heart defect. From a population base of 974,579 births during 1999–2004, we used multiplex ligation-dependent probe amplification to screen for microdeletions/duplications of ISL1 among 389 infants with tetralogy of Fallot or d-transposition of the great arteries (d-TGA). We also sequenced all exons of ISL1. We identified a novel 20-kb microdeletion encompassing the entire coding region of ISL1, but not including either flanking gene, from an infant with d-TGA. We confirmed that the deletion was caused by nonhomologous end joining mechanism. Sequencing of exons of ISL1 did not reveal any subject with a novel nonsynonymous mutation. This is the first report of an ISL1 mutation of a child with a congenital heart defect.
Osoegawa, Kazutoyo; Schultz, Kathleen; Yun, Kenneth; Mohammed, Nebil; Shaw, Gary M; Lammer, Edward J
Voltage-dependent anion channel-2 interaction with nitric oxide synthase enhances pulmonary artery endothelial cell nitric oxide production.
Increased pulmonary artery endothelial cell (PAEC) endothelium-dependent nitric oxide synthase (eNOS) activity mediates perinatal pulmonary vasodilation. Compromised eNOS activity is central to the pathogenesis of persistent pulmonary hypertension of the newborn (PPHN). Voltage-derived anion channel (VDAC)-1 was recently demonstrated to bind eNOS in the systemic circulation. We hypothesized that VDAC isoforms modulate eNOS activity in the pulmonary circulation, and that decreased VDAC expression contributes to PPHN. In PAECs derived from an ovine model of PPHN: (1) there is eNOS activity, but not expression; and (2) VDAC1 and -2 proteins are decreased. Immunocytochemistry, coimmunoprecipitation, and in situ proximity ligation assays in human PAECs (hPAECs) demonstrate binding between eNOS and both VDAC1 and -2, which increased upon stimulation with NO agonists. The ability of agonists to increase the eNOS/VDAC interaction was significantly blunted in hypertensive, compared with normotensive, ovine PAECs. Depletion of VDAC2, but not VDAC1, blocked the agonist-induced increase in eNOS activity in hPAECs. Overexpression of VDAC2 in hypertensive PAECs increased eNOS activity. Binding of VDAC2 enhances eNOS activity in the pulmonary circulation, and diminished VDAC2 constrains eNOS in PAECs derived from fetal lambs with chronic intrauterine pulmonary hypertension. We speculate that decreases in VDAC2 may contribute to the limited eNOS activity that characterizes pulmonary hypertension. PMID:22842492
Alvira, Cristina M; Umesh, Anita; Husted, Cristiana; Ying, Lihua; Hou, Yanli; Lyu, Shu-Chen; Nowak, Jeffrey; Cornfield, David N
Carotid Artery Stenosis: Comparison of 3D Time-of-Flight MR Angiography and Contrast-Enhanced MR Angiography at 3T
Purpose. The aim of this study was to assess the correlation of 3D time-of-flight MR angiography (TOF MRA) and contrast-enhanced MR angiography (CEMRA) for carotid artery stenosis evaluation at 3T. Material and Methods. Twenty-three patients (5?f, 18?m; mean age 61?y, age range 45–78?y) with internal carotid artery stenosis detected with ultrasonography were examined on a 3.0T MR system. The MR examination included both 3D TOF MRA and CEMRA of the carotid arteries. MR images were evaluated independently by two board-certified radiologists. Stenosis evaluation was based on a five-point scale. Stenosis grades determined by TOF and CEMRA were compared using Spearman's rank correlation coefficient and the Wilcoxon test. Cohen's Kappa was used to evaluate interrater reliability. Results. CEMRA detected stenosis in 24 (52%) of 46 carotids evaluated, while TOF detected stenosis in 27 (59%) of 46 carotids. TOF MRA yielded significantly higher results for stenosis grade in comparison to CEMRA (P = 0.014). Interrater agreement was very good for both TOF MRA (? = 0.93) and CEMRA (? = 0.93). Conclusion. At 3T, 3D TOF MRA should not be used as replacement for contrast-enhanced MRA of the carotid arteries, as it results in significantly higher stenosis grades.
Sieron, Dominik; Wiggermann, Philipp; Laniado, Michael
Early markers of cognitive enhancement: developing an implicit measure of cognitive performance.
There is intense interest in the development of effective cognitive enhancing drugs which would have therapeutic application across a number of neurological and psychological disorders including dementia, schizophrenia and depression. However, development in this area has been limited by the absence of sensitive biomarkers which can be used to detect and refine therapeutic-like action in phase 1 clinical studies. The aim of the present study was therefore to develop a measure of cognition relevant to the action of candidate cognitive enhancers which might be sensitive to pharmacological manipulation in healthy volunteers. Healthy volunteers (n?=?34) were randomised to receive a single dose of modafinil (100 mg) or placebo. Five hours post dose, attentional flexibility in learning was assessed using a novel implicit learning task. Volunteers also completed an auditory digit span task and visual analogue scales (VAS). Modafinil increased alertness as measured by the VAS. In the implicit learning task, modafinil enhanced learning rates in terms of both accuracy and reaction time, suggesting an increase in implicit rule learning. These results suggest that the novel learning task should be explored as a biomarker of early cognitive improvement which could be more sensitive than conventional measures. PMID:23820927
Pringle, Abbie; Browning, Michael; Parsons, Elizabeth; Cowen, Phil J; Harmer, Catherine J
The effect of blood inflow and B(1)-field inhomogeneity on measurement of the arterial input function in axial 3D spoiled gradient echo dynamic contrast-enhanced MRI.
A major potential confound in axial 3D dynamic contrast-enhanced magnetic resonance imaging studies is the blood inflow effect; therefore, the choice of slice location for arterial input function measurement within the imaging volume must be considered carefully. The objective of this study was to use computer simulations, flow phantom, and in vivo studies to describe and understand the effect of blood inflow on the measurement of the arterial input function. All experiments were done at 1.5 T using a typical 3D dynamic contrast-enhanced magnetic resonance imaging sequence, and arterial input functions were extracted for each slice in the imaging volume. We simulated a set of arterial input functions based on the same imaging parameters and accounted for blood inflow and radiofrequency field inhomogeneities. Measured arterial input functions along the vessel length from both in vivo and the flow phantom agreed with simulated arterial input functions and show large overestimations in the arterial input function in the first 30 mm of the vessel, whereas arterial input functions measured more centrally achieve accurate contrast agent concentrations. Use of inflow-affected arterial input functions in tracer kinetic modeling shows potential errors of up to 80% in tissue microvascular parameters. These errors emphasize the importance of careful placement of the arterial input function definition location to avoid the effects of blood inflow. PMID:20928889
Roberts, Caleb; Little, Ross; Watson, Yvonne; Zhao, Sha; Buckley, David L; Parker, Geoff J M
Early exercise testing and elective coronary artery bypass surgery after uncomplicated myocardial infarction. Effect on morbidity and mortality
One hundred and nineteen consecutive patients were studied prospectively after uncomplicated myocardial infarction by maximal exercise electrocardiography at two weeks and coronary angiography at six weeks. At angiography 87 patients had a stenosis greater than 70% in one major coronary artery supplying residual viable myocardium outside the infarction zone. In 82 (94%) of these the 12 lead maximal exercise electrocardiogram
F Akhras; J Upward; J Keates; G Jackson
Comparing the diagnostic accuracy of contrast-enhanced computed tomographic angiography and gadolinium-enhanced magnetic resonance angiography for the assessment of hemodynamically significant transplant renal artery stenosis.
To compare diagnostic accuracy of contrast-enhanced computed tomographic angiography (CTA) and gadolinium-enhanced magnetic resonance angiography (MRA) for the assessment of hemodynamically significant transplant renal artery stenosis (TRAS). After institutional review board approval, records of 27 patients with TRAS confirmed on digital subtraction angiography (DSA) were retrospectively reviewed. A total of 13 patients had MRA and 14 had CTA before DSA. Two board-certified fellowship-trained radiologists, one each from interventional radiology and body imaging blindly reviewed the DSA and CTA or MRA data, respectively. Sensitivity (SN), specificity (SP), positive predictive value, and negative predictive value of MRA and CTA were estimated using 50% stenosis as the detection threshold for significant TRAS. These parameters were compared between modalities using the Fisher exact test. Bias between MRA or CTA imaging and DSA was tested using the Wilcoxon signed-rank test. Two patients were excluded from the MRA group owing to susceptibility artifacts obscuring the TRAS. The correlation between MRA and DSA measurements of stenosis was r = 0.57 (95% CI:-0.02, 0.87; P = 0.052) and between CTA and DSA measurements was r = 0.63 (95% CI: 0.14, 0.87; P = 0.015); the difference between the 2 techniques was not significant (P = 0.7). Both imaging modalities tended to underestimate the degree of stenosis when compared with DSA. MRA group (SN and SP: 56% and 100%, respectively) and CTA group (SN and SP: 81% and 67%, respectively). There were no significant differences in detection performance between modalities (P>0.3 for all measures). We did not find that either modality had any advantage over the other in terms of measuring or detecting significant stenosis. Accordingly, MRA may be preferred over CTA after positive color Doppler ultrasound screening when not contraindicated owing to lack of ionizing radiation or nephrotoxic iodinated contrast. However, susceptibility of artifacts owing to surgical clips at the anastomosis may limit diagnostic utility of MRA as found in 2 of 13 patients. Trend towards no significant difference between the CTA and enhanced MRA in the detection of hemodynamically significant TRAS. PMID:24948209
Gaddikeri, Santhosh; Mitsumori, Lee; Vaidya, Sandeep; Hippe, Daniel S; Bhargava, Puneet; Dighe, Manjiri K
Impaired decidual natural killer cell regulation of vascular remodelling in early human pregnancies with high uterine artery resistance.
During human pregnancy, natural killer (NK) cells accumulate in the maternal decidua, but their specific roles remain to be determined. Decidual NK (dNK) cells are present during trophoblast invasion and uterine spiral artery remodelling. These events are crucial for successful placentation and the provision of an adequate blood supply to the developing fetus. Remodelling of spiral arteries is impaired in the dangerous pregnancy complication pre-eclampsia. We studied dNK cells isolated from pregnancies at 9-14 weeks' gestation, screened by uterine artery Doppler ultrasound to determine resistance indices which relate to the extent of spiral artery remodelling. dNK cells were able to promote the invasive behaviour of fetal trophoblast cells, partly through HGF. Cells isolated from pregnancies with higher resistance indices were less able to do this and secreted fewer pro-invasive factors. dNK cells from pregnancies with normal resistance indices could induce apoptotic changes in vascular smooth muscle and endothelial cells in vitro, events of importance in vessel remodelling, partly through Fas signalling. dNK cells isolated from high resistance index pregnancies failed to induce vascular apoptosis and secreted fewer pro-apoptotic factors. We have modelled the cellular interactions at the maternal-fetal interface and provide the first demonstration of a functional role for dNK cells in influencing vascular cells. A potential mechanism contributing to impaired vessel remodelling in pregnancies with a higher uterine artery resistance is presented. These findings may be informative in determining the cellular interactions contributing to the pathology of pregnancy disorders where remodelling is impaired, such as pre-eclampsia. PMID:22653829
Fraser, Rupsha; Whitley, Guy Stj; Johnstone, Alan P; Host, Amanda J; Sebire, Neil J; Thilaganathan, Baskaran; Cartwright, Judith E
Leukocytosis as an important risk factor for arterial thrombosis in WHO-defined early/prefibrotic myelofibrosis: an international study of 264 patients.
We aimed to determine risk factors for thrombotic events in early/prefibrotic myelofibrosis diagnosed according to the World Health Organization criteria. Multivariate Cox regression analysis was calculated on a total number of 264 patients derived from an international database. After a median follow-up of 6.28 years, 42 (15.9%) patients experienced arterial (n = 31) or venous thrombosis (n = 11). A higher leukocyte count correlated with an increased risk for total thrombosis and in particular, with an increased risk for arterial thrombosis (P = 0.005, HR 1.15 and P = 0.047, HR 1.12, respectively). A platelet count above 870 × 10?/L was associated with a lower risk for total thrombosis and also for venous thrombosis (P = 0.022, HR 0.44 and P = 0.027, HR 0.19). Moreover, a lower hemoglobin level was associated with an increased risk for venous thrombosis (P = 0.007, HR 0.59). Our data indicate that leukocytosis is a prominent risk factor for thrombosis in early/prefibrotic MF. PMID:22573503
Buxhofer-Ausch, Veronika; Gisslinger, Heinz; Thiele, Jürgen; Gisslinger, Bettina; Kvasnicka, Hans-Michael; Müllauer, Leonhard; Frantal, Sophie; Carobbio, Alessandra; Passamonti, Francesco; Rumi, Elisa; Ruggeri, Marco; Rodeghiero, Francesco; Randi, Maria L; Bertozzi, Irene; Vannucchi, Alessandro M; Antonioli, Elisabetta; Finazzi, Guido; Gangat, Naseema; Tefferi, Ayalew; Barbui, Tiziano
Enhanced early osteogenic differentiation by silicon-substituted hydroxyapatite ceramics fabricated via ultrasonic spray pyrolysis route.
The influence of silicon-substituted hydroxyapatite (Si-HAp) on osteogenic differentiation was assessed by biological analysis. Si-HAp was prepared by ultrasonic spray pyrolysis (USSP) technique using various amounts of Si (0, 0.8, and 1.6 mass%). Chemical analysis revealed that Si was incorporated into the hydroxyapatite (HAp) lattice with no other crystalline phase and which caused the change of crystal structure. Biological analyses showed that the Si contents affected the cell proliferation and morphology, suggesting that there is an optimal Si content for cell culture. As for differentiation, alkaline phosphatase activity and osteocalcin production of Si-HAp were higher than those of HAp. Gene expression profiles also revealed that substitution of Si (0.8 mass%) up-regulated the expression levels of osteocalcin and especially Runx2, a master gene for osteoblast development. These results suggest that incorporating Si into the HAp lattice may enhance the bioactivity, particularly during early osteoblast development. PMID:22890519
Honda, Michiyo; Kikushima, Koichi; Kawanobe, Yusuke; Konishi, Toshiisa; Mizumoto, Minori; Aizawa, Mamoru
Clinical and Magnetic Resonance Imaging Predictors of Very Early Neurological Response to Intravenous Thrombolysis in Patients With Middle Cerebral Artery Occlusion
Background The early identification of patients who are unlikely to respond to intravenous recombinant tissue plasminogen activator (IV?tPA) could help select candidates for additional intra?arterial therapy or add?on antithrombotic drugs during the acute stage of stroke. Given that very early neurological improvement (VENI) is a reliable surrogate of early recanalization, we assessed the clinical and magnetic resonance imaging predictors of lack of VENI. Methods and Results We reviewed consecutive ischemic stroke patients with middle cerebral artery occlusion and treated within 4.5 hours by IV?tPA between 2003 and 2012 in our center, where magnetic resonance imaging is systematically implemented as first?line diagnostic workup. Lack of VENI was defined as a <40% decrease in baseline National Institutes of Health Stroke Scale (NIHSS) score 1 hour after start of IV?tPA. Poor outcome was defined as a 3?month modified Rankin scale ?2. Associations between lack of VENI and potential determinants were assessed in logistic regression models. In all, 186 patients were included (median baseline NIHSS score, 16; median onset to treatment time, 155 minutes). One hundred forty?three patients (77%) had no VENI. The variables significantly associated with lack of VENI in multivariable analysis were baseline NIHSS (OR, 1.08; 95% CI, 1.01 to 1.16 per 1?point increase; P=0.03), onset to treatment time >120 minutes (OR, 2.94; 95% CI, 1.31 to 6.63; P=0.009) and diffusion weighted imaging—Alberta Stroke Programme Early CT Score ?5 (OR, 3.60; 95% CI, 1.14 to 11.35; P=0.03). Patients without VENI were more likely to have a modified Rankin Scale ?2 than those without VENI (68% versus 24%; OR, 5.01; 95% CI, 2.12 to 11.82) and less likely to have recanalization after 24 hours (OR, 0.41; 95% CI, 0.19 to 0.88). Conclusions Lack of VENI provides an early estimate of 3?month outcome and recanalization after IV?tPA. Baseline NIHSS, onset to treatment time, and diffusion weighted imaging—Alberta Stroke Programme Early CT Score could help to predict lack of VENI and, in turn, might help early selection of candidates for complementary reperfusion strategies.
Apoil, Marion; Turc, Guillaume; Tisserand, Marie; Calvet, David; Naggara, Olivier; Domigo, Valerie; Baron, Jean-Claude; Oppenheim, Catherine; Touze, Emmanuel
Senescent Fibroblasts Enhance Early Skin Carcinogenic Events via a Paracrine MMP-PAR-1 Axis
The incidence of carcinoma increases greatly with aging, but the cellular and molecular mechanisms underlying this correlation are only partly known. It is established that senescent fibroblasts promote the malignant progression of already-transformed cells through secretion of inflammatory mediators. We investigated here whether the senescent fibroblast secretome might have an impact on the very first stages of carcinogenesis. We chose the cultured normal primary human epidermal keratinocyte model, because after these cells reach the senescence plateau, cells with transformed and tumorigenic properties systematically and spontaneously emerge from the plateau. In the presence of medium conditioned by autologous senescent dermal fibroblasts, a higher frequency of post-senescence emergence was observed and the post-senescence emergent cells showed enhanced migratory properties and a more marked epithelial-mesenchymal transition. Using pharmacological inhibitors, siRNAs, and blocking antibodies, we demonstrated that the MMP-1 and MMP-2 matrix metalloproteinases, known to participate in late stages of cancer invasion and metastasis, are responsible for this enhancement of early migratory capacity. We present evidence that MMPs act by activating the protease-activated receptor 1 (PAR-1), whose expression is specifically increased in post-senescence emergent keratinocytes. The physiopathological relevance of these results was tested by analyzing MMP activity and PAR-1 expression in skin sections. Both were higher in skin sections from aged subjects than in ones from young subjects. Altogether, our results suggest that during aging, the dermal and epidermal skin compartments might be activated coordinately for initiation of skin carcinoma, via a paracrine axis in which MMPs secreted by senescent fibroblasts promote very early epithelial-mesenchymal transition of keratinocytes undergoing transformation and oversynthesizing the MMP-activatable receptor PAR-1.
Malaquin, Nicolas; Vercamer, Chantal; Bouali, Fatima; Martien, Sebastien; Deruy, Emeric; Wernert, Nicolas; Chwastyniak, Maggy; Pinet, Florence; Abbadie, Corinne; Pourtier, Albin
Emphysema early diagnosis using X-ray diffraction enhanced imaging at synchrotron light source
Background Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide, and emphysema is a common component of COPD. Currently, it is very difficult to detect early stage emphysema using conventional radiographic imaging without contrast agents, because the change in X-ray attenuation is not detectable with absorption-based radiography. Compared with the absorption-based CT, phase contrast imaging has more advantages in soft tissue imaging, because of its high spatial resolution and contrast. Methods In this article, we used diffraction enhanced imaging (DEI) method to get the images of early stage emphysematous and healthy samples, then extract X-ray absorption, refraction, and ultra-small-angle X-ray scattering (USAXS) information from DEI images using multiple image radiography (MIR). We combined the absorption image with the USAXS image by a scatter plot. The critical threshold in the scatter plot was calibrated using the linear discriminant function in the pattern recognition. Results USAXS image was sensitive to the change of tissue micro-structure, it could show the lesions which were invisible in the absorption image. Combined with the absorption-based image, the USAXS information enabled better discrimination between healthy and emphysematous lung tissue in a mouse model. The false-color images demonstrated that our method was capable of classifying healthy and emphysematous tissues. Conclusion Here we present USAXS images of early stage emphysematous and healthy samples, where the dependence of the USAXS signal on micro-structures of biomedical samples leads to improved diagnosis of emphysema in lung radiographs.
Early Impact of Prescription Omega3 Fatty Acids on Platelet Biomarkers in Patients with Coronary Artery Disease and Hypertriglyceridemia
Background: Prescription omega-3-acid ethyl esters (PO-3A) have been tested for outcome benefits in patients with coronary artery disease (CAD), arrhythmias and heart failure. Some evidence suggests that PO-3A may exert their benefit via inhibiting platelets. We tested the hypothesis that PO-3A may inhibit platelet activity in patients with documented stable CAD, beyond the antiplatelet properties of aspirin and statins. Methods:
Victor L. Serebruany; Michael Miller; Alex N. Pokov; Donald Lynch; Jesper K. Jensen; Jonas Hallén; Dan Atar
Time-Efficient Myocardial Contrast Partition Coefficient Measurement from Early Enhancement with Magnetic Resonance Imaging
Objective Our purpose was to validate an early enhancement time point for accurately measuring the myocardial contrast partition coefficient (lambda) using dynamic-equilibrium magnetic resonance imaging. Materials and Methods The pre- and post-contrast longitudinal relaxation rates (reciprocal of T1) of the interventricular septum (R1m) and blood pool (R1b) were obtained from fifteen healthy volunteers and three diabetic patients with hypertension using two optimized T1 mapping sequences (modified Look-Locker inversion recovery) on a 3-Tesla magnetic resonance scanner. Reference lambda values were calculated as the slope of the regression line of R1m versus R1b at dynamic equilibrium (multi-point regression method). The simplified pre-/post-enhancement two-acquisition method (two-point method) was used to calculate lambda by relating the change in R1m and R1b using different protocols according to the acquisition stage of the post-enhancement data point. The agreement with the referential method was tested by calculating Pearson's correlation coefficient and the intra-class correlation coefficient. Results The lambda values measured by the two-point method increased (from 0.479±0.041 to 0.534±0.043) over time from 6 to 45 minutes after contrast and exhibited good correlation with the reference at each time point (r?0.875, p<0.05). The intra-class correlation coefficient on absolute agreement with the reference lambda was 0.946, 0.929 and 0.922 at the 6th, 7th and 8th minutes and dropped from 0.878 to 0.403 from the 9th minute on. Conclusions The time-efficient two-point method at 6–8 minutes after the Gd-DTPA bolus injection exhibited good agreement with the multi-point regression method and can be applied for accurate lambda measurement in normal myocardium.
Zhang, Shi-Jun; Wang, Yi-Xiang; Yuan, Jing; Jin, Jiyang; Wang, Yuan-Cheng; Chang, Di; Weng, Dehe; Greiser, Andreas; Ju, Shenghong
Ultrasmall superparamagnetic iron oxide to enhance MRA of the renal and coronary arteries: Studies in human patients
Our goal was to determine the feasibility of using an intravascular MR contrast agent to improve 3D MRA. Three-dimensional TOF MRA was performed in nine patients both prior to and following the administration of an ultrasmall particle superparamagnetic iron oxide contrast agent (AMI 227). The lengths of both renal arteries were measured from the maximum intensity projection (MIP) images as well as the individual partitions. Seven of these patients also were studied by a 3D coronary artery MRA sequence. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements of the right coronary artery were determined both prior to and following the administration of AMI 227. Statistical analysis of both renal artery lengths and right coronary SNR and CNR was performed using a one tailed paired t test comparing pre- and postcontrast images. The renal artery lengths significantly increased (right renal artery: 30%, p = 0.001; left renal artery: 25%, p < 0.008) when measured from the individual axial slice partitions. No significant increase in length was observed on the MIP images following contrast. In the right coronary artery, the SNR increased by an average of 80% (p = 0.008) and CNR increased by an average of 109% (p = 0.007). Increased background signal and superimposed venous structures reduced the measurable lengths of the renal arteries from the MIP images. These studies support the hypothesis that 3D MRA in the body will benefit from the use of intravascular contrast agents. Nevertheless, conventional MIP processing is unable to reveal the full advantage of the contrast improvement. 14 refs., 6 figs., 2 tabs.
Stillman, A.E.; Wilke, N. [Univ. of Minnesota, Minneapolis, MN (United States)] [Univ. of Minnesota, Minneapolis, MN (United States); Li, D.; Haacke, E.M. [Washington Univ., St. Louis, MO (United States)] [Washington Univ., St. Louis, MO (United States); McLachlan, S. [Advanced Magnetics, Inc., Princeton, NJ (United States)] [Advanced Magnetics, Inc., Princeton, NJ (United States)
An Nkx-Dependent Enhancer Regulates cGATA-6 Gene Expression during Early Stages of Heart Development
The evolutionarily conserved GATA-6 transcription factor is an early and persistent marker of heart development in diverse vertebrate species. We previously found evidence for a functionally conserved heart-specific enhancer upstream of the chicken GATA-6 (cGATA-6) gene and in the present study we used transgenic mouse assays to further characterize this regulatory module. We show that this enhancer is activated in
Dorene L. Davis; Andy Wessels; John B. E. Burch
Radiological Diagnosis of Liver Tumours. Evaluation of Angiography and Intravenous and Intra-Arterially Enhanced Computed Tomography.
National Technical Information Service (NTIS)
Sixty patients treated with an intra-arterial cytostatic drug for metastases from colo-rectal carcinoma were evaluated with angiography to determine prognostic parameters. The extent of tumour in the liver and an unchanged or diminished tumour volume foll...
C. Lundstedt
Early increase in myocardial perfusion after stem cell therapy in patients undergoing incomplete coronary artery bypass surgery.
Incomplete revascularization is associated with worse long-term outcomes. Autologous bone marrow cells (BMC) have recently been tested in patients with severe coronary artery disease. We tested the hypothesis that intramyocardial injection of autologous BMC increases myocardial perfusion in patients undergoing incomplete coronary artery bypass grafting (CABG). Twenty-one patients (19 men), 59?±?7 years old, with limiting angina and multivessel coronary artery disease (CAD), not amenable to complete CABG were enrolled. BMC were obtained prior to surgery, and the lymphomonocytic fraction separated by density gradient centrifugation. During surgery, 5 mL containing 2.1?±?1.3?×?108 BMC (CD34+?=?0.8?±?0.3%) were injected in the ischemic non-revascularized myocardium. Myocardial perfusion was assessed by magnetic resonance imaging (MRI) at baseline and 1 month after surgery. The increase in myocardial perfusion was compared between patients with <50% (group A, n?=?11) with that of patients with >50% (group B, n?=?10) of target vessels (stenosis???70%) successfully bypassed. Injected myocardial segments included the inferior (n?=?12), anterior (n?=?7), and lateral (n?=?2) walls. The number of treated vessels (2.3?±?0.8) was significantly smaller than the number of target vessels (4.2?±?1.0; P?0.0001). One month after surgery, cardiac MRI showed a similar reduction (%) in the ischemic score of patients in group A (72.5?±?3.2), compared to patients in group B (78.1?±?3.2; P?=?.80). Intramyocardial injection of autologous BMC may help increase myocardial perfusion in patients undergoing incomplete CABG, even in those with fewer target vessels successfully treated. This strategy may be an adjunctive therapy for patients suffering from a more advanced (diffuse) CAD not amenable for complete direct revascularization. PMID:21061106
Gowdak, Luís Henrique Wolff; Schettert, Isolmar Tadeu; Rochitte, Carlos Eduardo; Lisboa, Luiz Augusto Ferreira; Dallan, Luís Alberto Oliveira; César, Luiz Antônio Machado; de Oliveira, Sérgio Almeida; Krieger, José Eduardo
Complementary tumor vascularity imaging in a single PET-CT routine using FDG early dynamic blood flow and contrast-enhanced CT texture analysis
NASA Astrophysics Data System (ADS)
A feasibility study of improved PET-CT tumor imaging approach is presented. A single PET-CT routine includes three different techniques: 18F-FDG early dynamic blood flow intended for perfusion assessment; standard late 18F-FDG uptake; and high-resolution contrast-enhanced CT enabling tissue texture analysis. Both PET protocols utilize the same single standard radiotracer dose administration. Quantitative volumetric arterial perfusion maps are derived from the reconstructed dynamic PET images corresponding to successive acquisition time intervals of 3 seconds only. For achieving high accuracy, the analysis algorithm differentiates the first-pass arterial flow from other interfering dynamic effects, and a noise reduction scheme based on adaptive total-variation minimization aims to provide appreciable quantitative map in physical conditions of high noise and low spatial resolution. The CT texture analysis comprises a practical and robust method for generating volumetric tissue irregularity maps. A local map value is represented by the entropy function which is derived from a weighted co-occurrence matrix histogram of the corresponding image voxel three-dimensional vicinity. Unique entropy scaling scheme and parameter optimization process, as well as appropriate scaling for varying image noise levels and contrast agent concentrations, improve the results toward quantitative absolute measure with respect to diverse scanning conditions and key analysis parameters. Representative imaging results are demonstrated on several clinical cases involving different organs and cancer types. In these cases, significant tumor characterization relative to the normal surrounding tissues is seen on the quantitative maps of all three imaging techniques. This proof of concept can lead the way to a new practical diagnostic imaging application.
Carmi, Raz; Yefremov, Nikolay; Bernstine, Hanna; Groshar, David
The chemokine GRO? mobilizes early hematopoietic stem cells characterized by enhanced homing and engraftment
Mobilized peripheral blood hematopoietic stem cells (PBSCs) demonstrate accelerated engraftment compared with bone marrow; however, mechanisms responsible for enhanced engraftment remain unknown. PBSCs mobilized by GRO? (GRO??4/CXCL2?4) or the combination of GRO??4 plus granulocyte colony-stimulating factor (G-CSF) restore neutrophil and platelet recovery faster than G-CSF–mobilized PBSCs. To determine mechanisms responsible for faster hematopoietic recovery, we characterized immunophenotype and function of the GRO?-mobilized grafts. PBSCs mobilized by GRO??4 alone or with G-CSF contained significantly more Sca-1+-c-kit+-lineage? (SKL) cells and more primitive CD34?-SKL cells compared with cells mobilized by G-CSF and demonstrated superior competitive long-term repopulation activity, which continued to increase in secondary and tertiary recipients. GRO??4-mobilized SKL cells adhered better to VCAM-1+ endothelial cells compared with G-CSF–mobilized cells. GRO??4-mobilized PBSCs did not migrate well to the chemokine stromal derived factor (SDF)-1? in vitro that was associated with higher CD26 expression. However, GRO??4-mobilized SKL and c-Kit+ lineage? (KL) cells homed more efficiently to marrow in vivo, which was not affected by selective CXCR4 and CD26 antagonists. These data suggest that GRO??4-mobilized PBSCs are superior in reconstituting long-term hematopoiesis, which results from differential mobilization of early stem cells with enhanced homing and long-term repopulating capacity. In addition, homing and engraftment of GRO??4-mobilized cells is less dependent on the SDF-1?/CXCR4 axis.
Fukuda, Seiji; Bian, Huimin; King, Andrew G.
How Will This Help Me? Evaluating an Accredited Programme to Enhance the Early Professional Development of Newly Qualified Teachers
ERIC Educational Resources Information Center
This article reports on the evaluation of an accredited programme to enhance the early professional development of newly qualified teachers within the Black Country region of the English West Midlands. Newly qualified teachers participating in the accredited programme, their induction tutors, newly qualified teachers not participating in the…
Rhodes, Christopher; Nevill, Alan; Allan, Jo
Identification of Patients at Risk for Early Onset and/or Severe Preeclampsia With the Use of Uterine Artery Doppler Velocimetry and Placental Growth Factor
OBJECTIVE: Preeclampsia has been proposed to be an anti-angiogenic state that may be detected by the determination of the concentrations of the soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and placental growth factor (PlGF) in maternal blood even before the clinical development of the disease. The purpose of this study was to determine the role of the combined use of uterine artery Doppler velocimetry (UADV) and maternal plasma PlGF and sVEGFR-1 concentrations in the second trimester for the identification of patients at risk for severe and/or early onset preeclampsia. STUDY DESIGN: A prospective cohort study was designed to examine the relationship between abnormal UADV and plasma concentrations of PlGF and sVEGFR-1 in 3348 pregnant women. Plasma samples were obtained between 22 and 26 weeks of gestation at the time of ultrasound examination. Abnormal UADV was defined as the presence of bilateral uterine artery notches and/or a mean pulsatility index above the 95th percentile for the gestational age. Maternal plasma PlGF and sVEGFR-1 concentrations were determined with the use of sensitive and specific immunoassays. The primary outcome was the development of early onset preeclampsia (?34 weeks of gestation) and/or severe preeclampsia. Secondary outcomes included preeclampsia, the delivery of a small for gestational age (SGA) neonate without preeclampsia, spontaneous preterm birth at ?32 and ?35 weeks of gestation, and a composite of severe neonatal morbidity. Contingency tables, chi-square test, receiver operating characteristic curve, and multivariate logistic regression were used for statistical analyses. A probability value of <.05 was considered significant. RESULTS: (1) The prevalence of preeclampsia, severe preeclampsia, and early onset preeclampsia were 3.4% (113/3296), 1.0% (33/3296), and 0.8% (25/3208), respectively. UADV was performed in 95.4% (3146/3296) and maternal plasma PlGF concentrations were determined in 93.5% (3081/3296) of the study population. (2) Abnormal UADV and a maternal plasma PlGF <280 pg/mL were independent risk factors for the occurrence of preeclampsia, severe preeclampsia, early onset preeclampsia, and SGA without preeclampsia. (3) Among patients with abnormal UADV, maternal plasma PlGF concentration contributed significantly in the identification of patients destined to develop early onset preeclampsia (area under the curve, 0.80; P<.001) and severe preeclampsia (area under the curve, 0.77; P<.001). (4) In contrast, maternal plasma sVEGFR-1 concentration was of limited use in the prediction of early onset and/or severe preeclampsia. (5) The combination of abnormal UADV and maternal plasma PlGF of <280 pg/mL was associated with an odds ratio (OR) of 43.8 (95% CI, 18.48-103.89) for the development of early onset preeclampsia, an OR of 37.4 (95% CI, 17.64-79.07) for the development of severe preeclampsia, an OR of 8.6 (95% CI, 5.35-13.74) for the development of preeclampsia, and an OR of 2.7 (95% CI, 1.73-4.26) for the delivery of a SGA neonate in the absence of preeclampsia. CONCLUSION: The combination of abnormal UADV and maternal plasma PlGF concentration of <280 pg/mL in the second trimester is associated with a high risk for preeclampsia and early onset and/or severe preeclampsia in a low-risk population. Among those with abnormal UADV, a maternal plasma concentration of PlGF of <280 pg/mL identifies most patients who will experience early onset and/or severe preeclampsia.
Espinoza, Jimmy; Romero, Roberto; Nien, Jyh Kae; Gomez, Ricardo; Kusanovic, Juan Pedro; Goncalves, Luis F.; Medina, Luis; Edwin, Sam; Hassan, Sonia; Carstens, Mario; Gonzalez, Rogelio
On-versus Off-Pump Coronary Artery Bypass Grafting: No Difference in Early Postoperative Kidney Function Based on TNF-? or C-Reactive Protein
Background/Aims There are controversial data about renal function following off-pump coronary artery bypass grafting (CABG). The present study aimed to evaluate renal function changes 24 h after on- and off-pump CABG, as well as renal function correlated with high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor-? (TNF-?). Methods Ninety patients with coronary artery disease referred to our center for CABG from July 2006 to November 2007 were enrolled in the study. Patients were equally and randomly divided in two groups, on- and off-pump. Serum levels of creatinine (Cr), blood urea nitrogen, creatinine clearance (CrCl), hs-CRP, and TNF-? were determined immediately before and 24 h after surgery. Results Cr and CrCl changes after surgery were not significantly different between the two groups; however, blood urea nitrogen levels after surgery were significantly higher in the on-pump group (p = 0.035). No statistically significant difference was noted between the two groups in terms of changes in levels of hs-CRP and TNF-? (p = 0.350 and 0.805, respectively). The changes in CrCl levels had no significant correlation with hs-CRP and TNF-?. Conclusions The early Cr and CrCl levels after surgery are not significantly different in on- and off-pump groups. The early renal function after on- or off-pump CABG is not correlated with the levels of inflammatory markers including hs-CRP and TNF-?.
Nezami, Nariman; Djavadzadegan, Hassan; Tabatabaie-Adl, Haleh; Hamdi, Amir; Ghobadi, Kazem; Ghorashi, Sona; Hajhosseini, Babak
A Case Study of the Use of Internet Photobook Technology to Enhance Early Childhood "Scientist" Identity
NASA Astrophysics Data System (ADS)
There are many influences on a child's identity. Photobook technology purposefully prepared around science explorations presents a modern opportunity to repeatedly trigger memories that reinforce the "me, as scientist" viewpoint. Semi-structured interviews at 6 and 8 years of age were conducted with a child who was the subject of a photobook of everyday science activities to gain insights into his thinking about the nature of science and how he interprets his younger self participating. Interview data were recorded, transcribed and analyzed using dimensions from the previously established parameters for the nature of science. The child's statements about his participation in the photos were matched to these dimensions to consider how he sees himself "doing science" through his early years. Preliminary findings suggest that the child recognizes elements of science and regards himself as an active participant. In both interviews, the child reinforces these views by the opportunity to revisit the experiences in the photobook. Affective components may motivate further science involvement as well: the child enjoyed the time and attention that the photos and discussion provided; the child took pride in being the subject of a book. This case study suggests that there is a fertile field of research to investigate how, for whom, and in what ways internet photobook technology may enhance a child's developing identity as capable science explorer.
Katz, Phyllis
Detection of buried targets using a new enhanced very early time electromagnetic (VETEM) prototype system
In this paper, numerical simulations of a new enhanced very early time electromagnetic (VETEM) prototype system are presented, where a horizontal transmitting loop and two horizontal receiving loops are used to detect buried targets, in which three loops share the same axis and the transmitter is located at the center of receivers. In the new VETEM system, the difference of signals from two receivers is taken to eliminate strong direct-signals from the transmitter and background clutter and furthermore to obtain a better SNR for buried targets. Because strong coupling exists between the transmitter and receivers, accurate analysis of the three-loop antenna system is required, for which a loop-tree basis function method has been utilized to overcome the low-frequency breakdown problem. In the analysis of scattering problem from buried targets, a conjugate gradient (CG) method with fast Fourier transform (FFT) is applied to solve the electric field integral equation. However, the convergence of such CG-FFT algorithm is extremely slow at very low frequencies. In order to increase the convergence rate, a frequency-hopping approach has been used. Finally, the primary, coupling, reflected, and scattered magnetic fields are evaluated at receiving loops to calculate the output electric current. Numerous simulation results are given to interpret the new VETEM system. Comparing with other single-transmitter-receiver systems, the new VETEM has better SNR and ability to reduce the clutter.
Cui, T. J.; Chew, W. C.; Aydiner, A. A.; Wright, D. L.; Smith, D. V.
Demonstration as a rate enhancer to changes in coordination during early skill acquisition.
We compared the nature and rate of change in intra-limb coordination in participants who observed a video model (model) with those who practised based on verbal guidance only (control). Sixteen male novices threw a ball towards a target with maximal velocity using a back-handed, reverse baseball pitch. Participants in the model group immediately changed their intra-limb relative motion to more closely resemble the model's relative motion pattern. This new coordination pattern, and concomitant changes in ball speed, was maintained throughout acquisition, without further change. In contrast, the control group showed no change in coordination or ball speed across acquisition. Our findings suggest that demonstrations act as a rate enhancer, conveying an immediate movement solution that is adopted early in acquisition. A model may constrain the learner to perceive and imitate the model's relative motion pattern as suggested by Scully and Newell (1985). The stability of this new movement pattern questions accounts of learning, which suggest that prescriptive, directed learning may result in the "soft assembly" of an inaccurate and temporary movement solution. PMID:17365545
Horn, Robert R; Williams, A Mark; Hayes, Spencer J; Hodges, Nicola J; Scott, Mark A
Enhanced inflammatory responses to toll-like receptor 2/4 stimulation in type 1 diabetic coronary artery endothelial cells: the effect of insulin
Background Endothelial inflammatory responses mediated by Toll-like receptors (TLRs), particularly TLR2 and TLR4, play an important role in atherogenesis. While Type 1 diabetes (T1D) promotes the development and progression of atherosclerosis, the effect of T1D on TLR2/4-mediated inflammatory responses in coronary artery endothelial cells (CAECs) remains unclear. Methods We tested the hypothesis that diabetic CAECs have enhanced inflammatory responses to TLR2/4 stimulation. Non-diabetic and diabetic CAECs were treated with TLR2 agonist peptidoglycan and TLR4 agonist lipopolysaccharide. The expression of ICAM-1, IL-6 and IL-8 were analyzed by real-time PCR, immunoblotting and ELISA, and NF-?B activation by immunoblotting and immunostaining. In additional experiments, insulin was added before TLR stimulation to determine whether insulin deficiency alone is responsible for the alteration of TLR2/4-mediated inflammatory responses. Results Stimulation of TLR2 or TLR4 induced NF-?B activation, and the expression of ICAM-1, IL-6 and IL-8. Interestingly, the expression of inflammatory mediators was significantly enhanced in diabetic cells. The enhanced inflammatory responses correlated with augmented NF-?B activation in the absence of a change in TLR2 or TLR4 protein levels. Further, pretreatment of diabetic cells with insulin failed to suppress the enhanced inflammatory responses. Conclusions Diabetic CAECs have enhanced inflammatory responses to stimulation of TLR2 or TLR4, and insulin alone is insufficient to correct the hyper-inflammatory responses. The mechanism underlying the enhanced inflammatory responses appears to be augmentation of pro-inflammatory signaling, rather than up-regulation of levels of TLR2 and TLR4. These findings suggest that diabetic CAECs adopt a hyper-inflammatory phenotype and that this endothelial phenotypic change may predispose coronary artery to atherogenesis.
Hepatic arterial chemotherapy for metastatic colorectal carcinoma.
In this review, the rationale of regional chemotherapy for treatment of hepatic metastases in advanced colorectal carcinoma is discussed. Pharmacokinetic principles and early clinical experience of hepatic arterial drug administration are summarised. The regional advantage of fluoropyrimidine compounds in this setting is well established, and recent evidence suggests that 5-fluorouracil (5-FU) is more efficacious than the analogue 5-fluoro-2'-deoxyuridine (FUDR). However, while significantly higher clinical response rates can be achieved with hepatic arterial infusion (HAI) chemotherapy compared with conventional intravenous drug administration, patient survival benefit is not significantly different. Several novel approaches to overcome the limitations of HAI therapy are currently being explored. These include concomitant use of biodegradable microspheres, which both slow tumour blood flow and enhance tumour drug uptake, and use of vasoactive agents to redistribute arterial blood flow towards tumours. In addition, novel chemotherapeutic agents which exploit unique biological characteristics of hepatic tumours are entering clinical trial.
de Takats, P. G.; Kerr, D. J.; Poole, C. J.; Warren, H. W.; McArdle, C. S.
Predicting the extent and location of coronary artery disease during the early postinfarction period by quantitative thallium-201 scintigraphy
The ability of quantitative thallium-201 scintigraphy to predict the extent and location of coronary artery disease before hospital discharge after acute myocardial infarction was evaluated in 52 patients. All patients underwent coronary angiography and serial thallium-201 imaging either at rest or after submaximal exercise stress. Two or three vessel disease was designated if abnormal thallium-201 uptake or washout patterns, or both, were seen in two or three vascular segments, respectively. Of 156 vessels analyzed in the 52 patients, 91 stenoses of 70 percent or greater were found by angiography. Seventy-four of these were predicted by scintigraphy. The specificity of scintigraphy for identifying vessel stenoses was 92 percent. Sensitivity for detecting and localizing stenoses supplying an infarct zone was 96 percent compared with 62 percent for stenoses supplying myocardium remote from the acute infarct. Perfusion abnormalities were more frequently seen in the distribution of vessels with severe stenoses than in those with moderate stenoses. Scintigraphy detected a greater proportion of left anterior descending and right coronary arterial stenoses than circumflex stenoses. In the 42 patients who underwent submaximal exercise testing, multivariate analysis of 23 clinical and laboratory variables identified multiple thallium-201 defects as the best predictor of multivessel disease. The predictive accuracy of exercise-induced S-T segment depression was only 45 percent compared with 88 percent for thallium-201 scintigraphy. Thallium-201 imaging at rest is reliable in assessing the extent of coronary disease in hospitalized patients who cannot undergo exercise testing because of unstable angina, uncompensated heart failure, poorly controlled arrhythmias or physical limitations.
Gibson, R.S.; Taylor, G.J.; Watson, D.D.; Stebbins, P.T.; Martin, R.P.; Crampton, R.S.; Beller, G.A.
Interferon-beta signaling is enhanced in patients with insufficient coronary collateral artery development and inhibits arteriogenesis in mice.
Stimulation of collateral artery growth in patients has been hitherto unsuccessful, despite promising experimental approaches. Circulating monocytes are involved in the growth of collateral arteries, a process also referred to as arteriogenesis. Patients show a large heterogeneity in their natural arteriogenic response on arterial obstruction. We hypothesized that circulating cell transcriptomes would provide mechanistic insights and new therapeutic strategies to stimulate arteriogenesis. Collateral flow index was measured in 45 patients with single-vessel coronary artery disease, separating collateral responders (collateral flow index, >0.21) and nonresponders (collateral flow index, < or 1). Isolated monocytes were stimulated with lipopolysaccharide or taken into macrophage culture for 20 hours to mimic their phenotype during arteriogenesis. Genome-wide mRNA expression analysis revealed 244 differentially expressed genes (adjusted P, <0.05) in stimulated monocytes. Interferon (IFN)-beta and several IFN-related genes showed increased mRNA levels in 3 of 4 cellular phenotypes from nonresponders. Macrophage gene expression correlated with stimulated monocytes, whereas resting monocytes and progenitor cells did not display differential gene regulation. In vitro, IFN-beta dose-dependently inhibited smooth muscle cell proliferation. In a murine hindlimb model, perfusion measured 7 days after femoral artery ligation showed attenuated arteriogenesis in IFN-beta-treated mice compared with controls (treatment versus control: 31.5+/-1.2% versus 41.9+/-1.9% perfusion restoration, P<0.01). In conclusion, patients with differing arteriogenic response as measured with collateral flow index display differential transcriptomes of stimulated monocytes. Nonresponders show increased expression of IFN-beta and its downstream targets, and IFN-beta attenuates proliferation of smooth muscle cells in vitro and hampers arteriogenesis in mice. Inhibition of IFN-beta signaling may serve as a novel approach for the stimulation of collateral artery growth. PMID:18420941
Schirmer, Stephan H; Fledderus, Joost O; Bot, Pieter T G; Moerland, Perry D; Hoefer, Imo E; Baan, Jan; Henriques, José P S; van der Schaaf, René J; Vis, Marije M; Horrevoets, Anton J G; Piek, Jan J; van Royen, Niels
Enhancing the Early Childhood Development System in Yakutia (Russia): Meeting the Challenges
The Yakutia Republic is currently working to update its early childhood development (ECD) system. Its goal is to ensure a high quality environment for early learning and child care and to enable higher enrolment levels.
Jure Kotnik; Tigran Shmis
No Child Misunderstood: Enhancing Early Childhood Teachers' Multicultural Responsiveness to the Social Competence of Diverse Children
ERIC Educational Resources Information Center
As a result of rapid demographic changes in our society, more children from diverse racial/cultural backgrounds join our early childhood classrooms. The majority of early childhood teachers, on the other hand, are middle-class and of European-decent. This paper provides early childhood teachers with both theoretical and practical understandings…
Han, Heejeong Sophia; Thomas, M. Shelley
Folic Acid Enhances Early Functional Recovery in a Piglet Model of Pediatric Head Injury
For stroke and spinal cord injury, folic acid supplementation has been shown to enhance neurodevelopment and to provide neuroprotection. We hypothesized that folic acid would reduce brain injury and improve neurological outcome in a neonatal piglet model of traumatic brain injury (TBI), using 4 experimental groups of 3- to 5-day-old female piglets. Two groups were intubated, anesthetized and had moderate brain injury induced by rapid axial head rotation without impact. One group of injured (Inj) animals received folic acid (Fol; 80 ?g/kg) by intraperitoneal (IP) injection 15 min following injury, and then daily for 6 days (Inj + Fol; n = 7). The second group of injured animals received an IP injection of saline (Sal) at the same time points (Inj + Sal; n = 8). Two uninjured (Uninj) control groups (Uninj + Fol, n = 8; Uninj + Sal, n = 7) were intubated, anesthetized and received folic acid (80 ?g/kg) or saline by IP injection at the same time points as the injured animals following a sham procedure. Animals underwent neurobehavioral and cognitive testing on days 1 and 4 following injury to assess behavior, memory, learning and problem solving. Serum folic acid and homocysteine levels were collected prior to injury and again before euthanasia. The piglets were euthanized 6 days following injury, and their brains were perfusion fixed for histological analysis. Folic acid levels were significantly higher in both Fol groups on day 6. Homocysteine levels were not affected by treatment. On day 1 following injury, the Inj + Fol group showed significantly more exploratory interest, and better motor function, learning and problem solving compared to the Inj + Sal group. Inj + Fol animals had a significantly lower cognitive composite dysfunction score compared to all other groups on day 1. These functional improvements were not seen on day 4 following injury. Axonal injury measured by ?-amyloid precursor protein staining 6 days after injury was not affected by treatment. These results suggest that folic acid may enhance early functional recovery in this piglet model of pediatric head injury. This is the first study to describe the application of complex functional testing to assess an intervention outcome in a swine model of TBI.
Naim, Maryam Y.; Friess, Stuart; Smith, Colin; Ralston, Jill; Ryall, Karen; Helfaer, Mark A.; Margulies, Susan S.
Folic acid enhances early functional recovery in a piglet model of pediatric head injury.
For stroke and spinal cord injury, folic acid supplementation has been shown to enhance neurodevelopment and to provide neuroprotection. We hypothesized that folic acid would reduce brain injury and improve neurological outcome in a neonatal piglet model of traumatic brain injury (TBI), using 4 experimental groups of 3- to 5-day-old female piglets. Two groups were intubated, anesthetized and had moderate brain injury induced by rapid axial head rotation without impact. One group of injured (Inj) animals received folic acid (Fol; 80 ?g/kg) by intraperitoneal (IP) injection 15 min following injury, and then daily for 6 days (Inj + Fol; n = 7). The second group of injured animals received an IP injection of saline (Sal) at the same time points (Inj + Sal; n = 8). Two uninjured (Uninj) control groups (Uninj + Fol, n = 8; Uninj + Sal, n = 7) were intubated, anesthetized and received folic acid (80 ?g/kg) or saline by IP injection at the same time points as the injured animals following a sham procedure. Animals underwent neurobehavioral and cognitive testing on days 1 and 4 following injury to assess behavior, memory, learning and problem solving. Serum folic acid and homocysteine levels were collected prior to injury and again before euthanasia. The piglets were euthanized 6 days following injury, and their brains were perfusion fixed for histological analysis. Folic acid levels were significantly higher in both Fol groups on day 6. Homocysteine levels were not affected by treatment. On day 1 following injury, the Inj + Fol group showed significantly more exploratory interest, and better motor function, learning and problem solving compared to the Inj + Sal group. Inj + Fol animals had a significantly lower cognitive composite dysfunction score compared to all other groups on day 1. These functional improvements were not seen on day 4 following injury. Axonal injury measured by ?-amyloid precursor protein staining 6 days after injury was not affected by treatment. These results suggest that folic acid may enhance early functional recovery in this piglet model of pediatric head injury. This is the first study to describe the application of complex functional testing to assess an intervention outcome in a swine model of TBI. PMID:21212637
Naim, Maryam Y; Friess, Stuart; Smith, Colin; Ralston, Jill; Ryall, Karen; Helfaer, Mark A; Margulies, Susan S
Quantitative assessment of regional cerebral blood flow by dynamic susceptibility contrast-enhanced MRI, without the need for arterial blood signals
NASA Astrophysics Data System (ADS)
In dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI), an arterial input function (AIF) is usually obtained from a time-concentration curve (TCC) of the cerebral artery. This study was aimed at developing an alternative technique for reconstructing AIF from TCCs of multiple brain regions. AIF was formulated by a multi-exponential function using four parameters, and the parameters were determined so that the AIF curves convolved with a model of tissue response reproduced the measured TCCs for 20 regions. Systematic simulations were performed to evaluate the effects of possible error sources. DSC-MRI and positron emission tomography (PET) studies were performed on 14 patients with major cerebral artery occlusion. Cerebral blood flow (CBF) images were calculated from DSC-MRI data, using our novel method alongside conventional AIF estimations, and compared with those from 15O-PET. Simulations showed that the calculated CBF values were sensitive to variations in the assumptions regarding cerebral blood volume. Nevertheless, AIFs were reasonably reconstructed for all patients. The difference in CBF values between DSC-MRI and PET was -2.2 ± 7.4 ml/100 g/min (r = 0.55, p < 0.01) for our method, versus -0.2 ± 8.2 ml/100 g/min (r = 0.47, p = 0.01) for the conventional method. The difference in the ratio of affected to unaffected hemispheres between DSC-MRI and PET was 0.07 ± 0.09 (r = 0.82, p < 0.01) for our method, versus 0.07 ± 0.09 (r = 0.83, p < 0.01) for the conventional method. The contrasts in CBF images from our method were the same as those from the conventional method. These findings suggest the feasibility of assessing CBF without arterial blood signals.
Enmi, Jun-ichiro; Kudomi, Nobuyuki; Hayashi, Takuya; Yamamoto, Akihide; Iguchi, Satoshi; Moriguchi, Tetsuaki; Hori, Yuki; Koshino, Kazuhiro; Zeniya, Tsutomu; Shah, Nadim Jon; Yamada, Naoaki; Iida, Hidehiro
Value of Single-Dose Contrast-Enhanced Magnetic Resonance Angiography Versus Intraarterial Digital Subtraction Angiography in Therapy Indications in Abdominal and Iliac Arteries
The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committee was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30{sup o}, field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses {>=}50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies.
Schaefer, Philipp J., E-mail: firstname.lastname@example.com; Schaefer, Fritz K. W.; Mueller-Huelsbeck, Stefan; Both, Markus; Heller, Martin; Jahnke, Thomas [University Hospital Schleswig-Holstein Campus Kiel, Department of Diagnostic Radiology (Germany)
Comparison of diagnostic accuracy of Doppler USG and contrast-enhanced magnetic resonance angiography and selective renal arteriography in patients with atherosclerotic renal artery stenosis
Background There are many systemic complications of conventional selective renal arteriography (SRA), such as contrast-mediated nephropathy. Contrast-enhanced magnetic resonance angiography (CE-MRA) and renal artery Doppler ultrasonography (DUSG) have been used increasingly for renal artery stenosis (RAS). The aim of this study was to evaluate the accuracy of CE-MRA and DUSG as used for diagnosis of RAS. Material/Methods We divided 130 consecutive patients investigated for resistant hypertension into 2 groups based on age: group 1 was patients <60 years old and group 2 was patients >60 year. DUSG, CE-MRA, and SRA were performed in group 1 and group 2 patients. Results Seventy-two patients (24 males [M], 48 females [F]) in group 1, and 58 patients (26 M, 32 F) in group 2 were included in the study. In the evaluation of clinically significant renal artery stenosis with DUSG, in group 1 the overall sensitivity was 83.33% and overall specificity was 81.82%, and in group 2 they were 69.23% and 0%, respectively, when compared with SRA. In the evaluation of clinically significant renal artery stenosis with CE-MRA, the overall sensitivity and specificity were 92.31% and 36.36%, respectively, in group 1 and 100.00% and 73.33%, respectively in group 2, when compared with SRA. Conclusions CE-MRA is an accurate, non-invasive method for the diagnosis of RAS in patients above 60 years of age and DUSG may be the choice of diagnostic method for RAS in patients under 60 years of age.
Turgutalp, Kenan; Kiykim, Ahmet; Ozhan, Onur; Helvaci, Ilter; Ozcan, Turkay; Y?ld?z, Altan
The Effect of Helium-enhanced Stellar Populations on the Ultraviolet-upturn Phenomenon of Early-type Galaxies
NASA Astrophysics Data System (ADS)
Recent observations and modeling of globular clusters (GCs) with multiple populations strongly indicate the presence of super-helium-rich subpopulations in old stellar systems. Motivated by this, we have constructed new population synthesis models with and without helium-enhanced subpopulations to investigate their impact on the UV-upturn phenomenon of quiescent early-type galaxies (ETGs). We find that our models with helium-enhanced subpopulations can naturally reproduce the strong UV-upturns observed in giant elliptical galaxies assuming an age similar to that of old GCs in the Milky Way. The major source of far-UV (FUV) flux, in this model, is relatively metal-poor and helium-enhanced hot horizontal-branch stars and their progeny. The Burstein et al. relation of the FUV - V color with metallicity is also explained either by the variation of the fraction of helium-enhanced subpopulations or by the spread in mean age of stellar populations in ETGs.
Chung, Chul; Yoon, Suk-Jin; Lee, Young-Wook
Total arterial revascularization with an internal thoracic artery and radial artery T graft
Background. Proximal anastomosis of the radial artery to the side of the internal thoracic artery (ITA) permits complete arterial revascularization in most patients, with the aim of improving long-term results of coronary artery bypass through greater long-term graft patency. The short-term results, however, have yet to be defined. We therefore reviewed our early experience with this grafting strategy.Methods. Between October
Thoralf M Sundt; Hendrick B Barner; Cynthia J Camillo; William A Gay
Total Arterial Revascularization With an Internal Thoracic Artery and Radial Artery T Graft
Background. Proximal anastomosis of the radial artery to the side of the internal thoracic artery (ITA) permits complete arterial revascularization in most patients, with the aim of improving long-term results of coronary artery bypass through greater long-term graft patency. The short-term results, however, have yet to be defined. We therefore reviewed our early experience with this graft- ing strategy. Methods.
Thoralf M. Sundt III; Hendrick B. Barner; Cynthia J. Camillo; William A. Gay
Umbilical artery blood S100? protein: a tool for the early identification of neonatal hypoxic-ischemic encephalopathy
Neuroprotective interventions in neonatal hypoxic-ischemic encephalopathy (HIE) require early indicators of brain damage to\\u000a initiate therapy. In order to find a reliable, rapid, and simple method to identify infants at risk for this disorder, 40\\u000a infants with asphyxia were selected as the observation group (HIE group) and 25 normal-term infants as the control group.\\u000a S100? protein concentration and gas analysis
Jing Qian; Dong Zhou; Yu-Wei Wang
Enhancer blocking activity located near the 3? end of the sea urchin early H2A histone gene
The sea urchin early histone repeating unit contains one copy of each of the five histone genes whose coordinate expression during development is regulated by gene-specific elements. To learn how within the histone repeating unit a gene-specific activator can be prevented to communicate with the heterologous promoters, we searched for domain boundaries by using the enhancer blocking assay. We focused on the region near the 3? end of the H2A gene where stage-specific nuclease cleavage sites appear upon silencing of the early histone genes. We demonstrated that a DNA fragment of 265 bp in length, defined as sns (for silencing nucleoprotein structure), blocked the enhancer activity of the H2A modulator in microinjected sea urchin embryos only when placed between the enhancer elements and the promoter. We also found that sns silenced the modulator elements even when placed at 2.7 kb from the promoter. By contrast, the enhancer activity of the modulator sequences, located downstream to the coding region, was not affected when sns was positioned in close proximity to the promoter. Finally, the H2A sns fragment placed between the simian virus 40 regulative region and the tk promoter repressed chloramphenicol acetyltransferase expression in transfected human cell lines. We conclude that 3? end of the H2A gene contains sequence elements that behave as functional barriers of enhancer function in the enhancer blocking assay. Furthermore, our results also indicate that the enhancer blocking function of sns lacks enhancer and species specificity and that it can act in transient assays.
Palla, Franco; Melfi, Raffaella; Anello, Letizia; Di Bernardo, Maria; Spinelli, Giovanni
Risk Factors for Long-term Outcome of Drug-eluting Stenting in Adults with Early-onset Coronary Artery Disease
Objective We lack data on the long-term outcome of drug-eluting stenting in patients with early-onset coronary artery disease (CAD). Here, we investigated the association of traditional risk factors and major adverse cardiovascular events (MACEs) after drug-eluting stenting in patients with CAD who were < 50 years old. Methods We enrolled 437 consecutive CAD patients < 50 years old who underwent drug-eluting stenting and 132 subjects who were age- and sex-matched and angiographically shown to be disease free as controls. MACEs were analyzed in CAD patients for a median of 24 months [interquartile range 14-34 months]. Results Male patients accounted for 90.4% of cases. As compared with controls, patients with early-onset CAD had higher body mass index and rates of smoking, family history of CAD, and diabetes and hypercholesterolemia. During the hospital stay, 1 patient died, and the incidence of MACEs was 1.1%. At the end of follow-up, the overall death rate was 0.7%. MACEs were observed in 54 patients (12.4%). On Cox proportional hazard analyses, positive family history and diabetes were independent risk factors of MACEs (HR 2.61, 95% confidence interval 1.29-4.00, p = 0.002; and HR 2.48, 95% confidence interval 0.86-3.14, p = 0.004, respectively). Conclusions Drug-eluting stenting is a reliable treatment for patients with early-onset CAD. Positive family history of CAD and diabetes are independent risk factors of adverse cardiovascular events in this subgroup of patients after drug-eluting stent implantation.
An, Guipeng; Du, Zhongqi; Meng, Xiao; Guo, Tao; Li, Guishuang; Chen, Yuguo; Li, Jifu; An, Fengshuang; Zhang, Yun; Li, Wenjing; Zhang, Cheng
Accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl for prediction of graft patency early and late after coronary artery bypass surgery. A controlled prospective study
To assess the accuracy of serial myocardial perfusion scintigraphy with /sup 201/Tl to predict graft patency early and late coronary artery bypass surgery, rest and exercise /sup 201/Tl and coronary arteriography were performed preoperatively and 2 weeks and 1 year after operation. The scintigraphic results were compared with graft patency, symptoms, left ventricular function and physical work capacity in a consecutive series of 55 patients with a total of 154 grafts. Serial /sup 201/Tl had an 80% sensitivity, 88% specificity and 86% overall accuracy in detecting or excluding graft occlusion, which was predicted by reversible ischemia as well as persistent new scar segments. Occluded grafts were correctly localized by /sup 201/Tl scintigraphy in 61%. Postoperative apical /sup 201/Tl defects were frequent (two-thirds of cases), and were the result of intraoperative transapical venting of the left ventricle. After coronary bypass graft surgery, ejection fraction at rest was unchanged. Left ventricular end-diastolic pressure and physical work capacity improved significantly. In the presence of new perfusion defects detected postoperatively, physical work capacity was reduced significantly. New /sup 201/Tl defects in addition to typical or atypical angina provided a high probability of graft occlusion, while in the absence of new /sup 201/Tl defects all grafts were patent in more than 90% of patients, all of whom had no or only atypical chest pain. We conclude that serial /sup 201/Tl imaging after coronary artery bypass surgery is an accurate noninvasive method that can be used routinely to assess graft function, to localize spatially occluded grafts and to identify patients with a high likelihood of graft occlusion who may need invasive studies.
Pfisterer, M.; Emmenegger, H.; Schmitt, H.E.; Mueller-Brand, J.; Hasse, J.; Graedel, E.; Laver, M.B.; Burckhardt, D.; Burkart, F.
The use of preintervention and postintervention thallium imaging for assessing the early and late effects of experimental coronary arterial reperfusion in dogs
To determine if thallium-201 imaging of myocardial perfusion can be used as an early predictor of myocardial salvage after reperfusion, 24 adult dogs were subjected to complete occlusion of the left anterior descending coronary artery with release of the snare 2 hr later. Separate doses of thallium (1 mCi) and microspheres were given 15 min before, 5 min after, and 1 hr after release of the snare. Gamma camera images of the heart were obtained after each injection of thallium. Preinjection images were also acquired before the second and third doses and were subtracted from the postinjection images to eliminate the counts due to residual activity from the prior injections. The chest was then closed and the dog allowed to recover. The chest was reopened 48 hr later, final doses of thallium and microspheres were administered, and the heart was imaged. After the dog was killed, the left ventricle was sliced from apex to base, and any infarct was outlined with triphenyltetrazolium (TTC) staining. The slices were then subdivided into pieces of approximately 1 g each and then well counted for microsphere determination of regional myocardial blood flows. Thallium images were interpreted qualitatively and quantitatively. Fifteen dogs with myocardial infarctions, as assessed by TTC staining, all had thallium image defects during coronary arterial occlusion. Thallium scans obtained immediately after reperfusion demonstrated increased anterior wall thallium activity in nine dogs, normal activity in four dogs, and decreased activity in two dogs. In 14 of the 15 dogs, relative thallium activity correlated with the occlusion/normal zone flow ratios.
Okada, R.D.; Pohost, G.M.
A very strong enhancer is located upstream of an immediate early gene of human cytomegalovirus
Summary A strong transcription enhancer was identified in the genomic DNA (235 kb) of human cytomegalovirus (HCMV), a ubiquitous and severe pathogen of the herpesvirus group. Cotransfection of enhancerless SV40 DNA with randomly fragmented HCMV DNA yielded two SV40-HCMV recombinant viruses that had incorporated overlapping segments of HCMV DNA to substitute for the missing SV40 enhancer. Within HCMV, these enhancer
Michael Boshart; Frank Weber; Gerhard Jahn; K DORSCHHLER; Bernhard Fleckenstein; W SCHAFFNER
Activation of Notch signaling by short-term treatment with Jagged-1 enhances store-operated Ca(2+) entry in human pulmonary arterial smooth muscle cells.
Notch signaling plays a critical role in controlling proliferation and differentiation of pulmonary arterial smooth muscle cells (PASMC). Upregulated Notch ligands and Notch3 receptors in PASMC have been reported to promote the development of pulmonary vascular remodeling in patients with pulmonary arterial hypertension (PAH) and in animals with experimental pulmonary hypertension. Activation of Notch receptors by their ligands leads to the cleavage of the Notch intracellular domain (NICD) to the cytosol by ?-secretase; NICD then translocates into the nucleus to regulate gene transcription. In this study, we examined whether short-term activation of Notch functionally regulates store-operated Ca(2+) entry (SOCE) in human PASMC. Treatment of PASMC with the active fragment of human Jagged-1 protein (Jag-1) for 15-60 min significantly increased the amplitude of SOCE induced by passive deletion of Ca(2+) from the intracellular stores, the sarcoplasmic reticulum (SR). The Jag-1-induced enhancement of SOCE was time dependent: the amplitude was maximized at 30 min of treatment with Jag-1, which was closely correlated with the time course of Jag-1-mediated increase in NICD protein level. The scrambled peptide of Jag-1 active fragment had no effect on SOCE. Inhibition of ?-secretase by N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester (DAPT) significantly attenuated the Jag-1-induced augmentation of SOCE. In addition to the short-term effect, prolonged treatment of PASMC with Jag-1 for 48 h also markedly enhanced the amplitude of SOCE. These data demonstrate that short-term activation of Notch signaling enhances SOCE in PASMC; the NICD-mediated functional interaction with store-operated Ca(2+) channels (SOC) may be involved in the Jag-1-mediated enhancement of SOCE in human PASMC. PMID:24573085
Yamamura, Hisao; Yamamura, Aya; Ko, Eun A; Pohl, Nicole M; Smith, Kimberly A; Zeifman, Amy; Powell, Frank L; Thistlethwaite, Patricia A; Yuan, Jason X-J
Bacteria present in carotid arterial plaques are found as biofilm deposits which may contribute to enhanced risk of plaque rupture.
Atherosclerosis, a disease condition resulting from the buildup of fatty plaque deposits within arterial walls, is the major underlying cause of ischemia (restriction of the blood), leading to obstruction of peripheral arteries, congestive heart failure, heart attack, and stroke in humans. Emerging research indicates that factors including inflammation and infection may play a key role in the progression of atherosclerosis. In the current work, atherosclerotic carotid artery explants from 15 patients were all shown to test positive for the presence of eubacterial 16S rRNA genes. Density gradient gel electrophoresis of 5 of these samples revealed that each contained 10 or more distinct 16S rRNA gene sequences. Direct microscopic observation of transverse sections from 5 diseased carotid arteries analyzed with a eubacterium-specific peptide nucleic acid probe revealed these to have formed biofilm deposits, with from 1 to 6 deposits per thin section of plaque analyzed. A majority, 93%, of deposits was located proximal to the internal elastic lamina and associated with fibrous tissue. In 6 of the 15 plaques analyzed, 16S rRNA genes from Pseudomonas spp. were detected. Pseudomonas aeruginosa biofilms have been shown in our lab to undergo a dispersion response when challenged with free iron in vitro. Iron is known to be released into the blood by transferrin following interaction with catecholamine hormones, such as norepinephrine. Experiments performed in vitro showed that addition of physiologically relevant levels of norepinephrine induced dispersion of P. aeruginosa biofilms when grown under low iron conditions in the presence but not in the absence of physiological levels of transferrin. Importance: The association of bacteria with atherosclerosis has been only superficially studied, with little attention focused on the potential of bacteria to form biofilms within arterial plaques. In the current work, we show that bacteria form biofilm deposits within carotid arterial plaques, and we demonstrate that one species we have identified in plaques can be stimulated in vitro to undergo a biofilm dispersion response when challenged with physiologically relevant levels of norepinephrine in the presence of transferrin. Biofilm dispersion is characterized by the release of bacterial enzymes into the surroundings of biofilm microcolonies, allowing bacteria to escape the biofilm matrix. We believe these enzymes may have the potential to damage surrounding tissues and facilitate plaque rupture if norepinephrine is able to stimulate biofilm dispersion in vivo. This research, therefore, suggests a potential mechanistic link between hormonal state and the potential for heart attack and stroke. PMID:24917599
Lanter, Bernard B; Sauer, Karin; Davies, David G
Exercise training enhances insulin-stimulated nerve arterial vasodilation in rats with insulin-treated experimental diabetes.
Insulin stimulates nerve arterial vasodilation through a nitric oxide (NO) synthase (NOS) mechanism. Experimental diabetes reduces vasa nervorum NO reactivity. Studies investigating hyperglycemia and nerve arterial vasodilation typically omit insulin treatment and use sedentary rats resulting in severe hyperglycemia. We tested the hypotheses that 1) insulin-treated experimental diabetes and inactivity (DS rats) will attenuate insulin-mediated nerve arterial vasodilation, and 2) deficits in vasodilation in DS rats will be overcome by concurrent exercise training (DX rats; 75-85% V?o2 max, 1 h/day, 5 days/wk, for 10 wk). The baseline index of vascular conductance values (VCi = nerve blood flow velocity/mean arterial blood pressure) were similar (P ? 0.68), but peak VCi and the area under the curve (AUCi) for the VCi during a euglycemic hyperinsulinemic clamp (EHC; 10 mU·kg(-1)·min(-1)) were lower in DS rats versus control sedentary (CS) rats and DX rats (P ? 0.01). Motor nerve conduction velocity (MNCV) was lower in DS rats versus CS rats and DX rats (P ? 0.01). When compared with DS rats, DX rats expressed greater nerve endothelial NOS (eNOS) protein content (P = 0.04). In a separate analysis, we examined the impact of diabetes in exercise-trained rats alone. When compared with exercise-trained control rats (CX), DX rats had a lower AUCi during the EHC, lower MNCV values, and lower sciatic nerve eNOS protein content (P ? 0.03). Therefore, vasa nervorum and motor nerve function are impaired in DS rats. Such deficits in rats with diabetes can be overcome by concurrent exercise training. However, in exercise-trained rats (CX and DX groups), moderate hyperglycemia lowers vasa nervorum and nerve function. PMID:24740656
Olver, T Dylan; McDonald, Matthew W; Grisé, Kenneth N; Dey, Adwitia; Allen, Matti D; Medeiros, Philip J; Lacefield, James C; Jackson, Dwayne N; Rice, Charles L; Melling, C W James; Noble, Earl G; Shoemaker, J Kevin
Bacteria Present in Carotid Arterial Plaques Are Found as Biofilm Deposits Which May Contribute to Enhanced Risk of Plaque Rupture
ABSTRACT Atherosclerosis, a disease condition resulting from the buildup of fatty plaque deposits within arterial walls, is the major underlying cause of ischemia (restriction of the blood), leading to obstruction of peripheral arteries, congestive heart failure, heart attack, and stroke in humans. Emerging research indicates that factors including inflammation and infection may play a key role in the progression of atherosclerosis. In the current work, atherosclerotic carotid artery explants from 15 patients were all shown to test positive for the presence of eubacterial 16S rRNA genes. Density gradient gel electrophoresis of 5 of these samples revealed that each contained 10 or more distinct 16S rRNA gene sequences. Direct microscopic observation of transverse sections from 5 diseased carotid arteries analyzed with a eubacterium-specific peptide nucleic acid probe revealed these to have formed biofilm deposits, with from 1 to 6 deposits per thin section of plaque analyzed. A majority, 93%, of deposits was located proximal to the internal elastic lamina and associated with fibrous tissue. In 6 of the 15 plaques analyzed, 16S rRNA genes from Pseudomonas spp. were detected. Pseudomonas aeruginosa biofilms have been shown in our lab to undergo a dispersion response when challenged with free iron in vitro. Iron is known to be released into the blood by transferrin following interaction with catecholamine hormones, such as norepinephrine. Experiments performed in vitro showed that addition of physiologically relevant levels of norepinephrine induced dispersion of P. aeruginosa biofilms when grown under low iron conditions in the presence but not in the absence of physiological levels of transferrin.
Lanter, Bernard B.; Sauer, Karin
Effects of Cognitive Enhancement Therapy on Employment Outcomes in Early Schizophrenia: Results From a Two-Year Randomized Trial
Objective To examine the effects of psychosocial cognitive rehabilitation on employment outcomes in a randomized controlled trial for individuals with early course schizophrenia. Method Early course schizophrenia outpatients (N = 58) were randomly assigned to Cognitive Enhancement Therapy (CET) or an Enriched Supportive Therapy (EST) control and treated for two years. Comprehensive data on cognition and employment were collected annually. Results Individuals treated with CET were significantly more likely to be competitively employed, had greater earnings from employment, and were more satisfied with their employment status by the end of treatment compared to EST recipients. Mediator analyses revealed that improvements in both social and non-social cognition mediated the CET effects on employment. Conclusion CET can help facilitate employment in early schizophrenia, by addressing the cognitive impairments that limit functioning in the disorder. Inclusion of cognitive rehabilitation in social work practice can support more optimal functional recovery from schizophrenia.
Eack, Shaun M.; Hogarty, Gerard E.; Greenwald, Deborah P.; Hogarty, Susan S.; Keshavan, Matcheri S.
Early Detection of Ovarian Cancer by Contrast-Enhanced Ultrasound- Targeted Imaging.
National Technical Information Service (NTIS)
Due to the lack of an early detection test, most cases of OVCA are detected at late stages when the 5-year survival rate is < 10% Transvaginal ultrasound (TVUS) imaging, the currently favored method, it cannot detect OVCA at early stage due to its limited...
A. Barua
Enhancing Research and Practice in Early Childhood through Formative and Design Experiments
ERIC Educational Resources Information Center
This article describes formative and design experiments and how they can advance research and instructional practices in early childhood education. We argue that this relatively new approach to education research closes the gap between research and practice, and it addresses limitations that have been identified in early childhood research. We…
Bradley, Barbara A.; Reinking, David
Improving Early Adaptation Following Long Duration Spaceflight by Enhancing Vestibular Information
NASA Technical Reports Server (NTRS)
Crewmember adapted to the microgravity state may need to egress the vehicle within a few minutes for safety and operational reasons after g-transitions. The transition from one sensorimotor state to another consists of two main mechanisms: strategic and plastic-adaptive and have been demonstrated in astronauts returning after long duration space flight. Strategic modifications represent "early adaptation" -immediate and transitory changes in control that are employed to deal with short-term changes in the environment. If these modifications are prolonged then plastic-adaptive changes are evoked that modify central nervous system function, automating new behavioral responses. More importantly, this longer term adaptive recovery mechanism was significantly associated with their strategic ability to recover on the first day after return to Earth G. We are developing a method based on stochastic resonance (SR) to enhance information transfer by improving the brain's ability to detect vestibular signals especially when combined with balance training exercises for rapid improvement in functional skill, for standing and mobility. The countermeasure to improve post-flight balance and locomotor disturbances is a stimulus delivery system that is wearable/portable providing low imperceptible levels of white noise based binaural bipolar electrical stimulation of the vestibular system (stochastic vestibular stimulation, SVS). The techniques for improving signal detection using SVS may thus provide additional information to improve such strategic abilities and thus help in significantly reducing the number of days required to recover functional performance to preflight levels after long duration space flight. We have conducted a series of studies to document the efficacy of SVS stimulation on balance/locomotion tasks on unstable surfaces and motion tracking tasks during intra-vestibular system conflicts. In an initial study, we showed that SVS improved overall balance performance while standing on an unstable surface indicating that SVS may be sufficient to provide a comprehensive countermeasure approach for improving postural stability. In a second study, we showed that SVS improved locomotor performance on a treadmill mounted on an oscillating platform indicating that SVS may also be used to maximize locomotor performance during walking in unstable environments. In a third study, SVS was evaluated during an otolith-canal conflict scenario in a variable radius centrifuge at low frequency of oscillation (0.1 Hz) on both eye movements and perceptual responses (using a joystick) to track imposed oscillations. The variable radius centrifuge provides a selective tilting sensation that is detectable only by the otolith organs providing conflicting information from the canal organs of the vestibular system (intra-vestibular conflict). Results show that SVS significantly reduced the timing difference between both the eye movement responses as well as the perceptual tracking responses with respect to the imposed tilt sensations. These results indicate that SVS can improve performance in sensory conflict scenarios like that experienced during space flight. Such a SR countermeasure will act synergistically along with the pre-and in-flight adaptability training protocols providing an integrated, multi-disciplinary countermeasure capable of fulfilling multiple requirements making it a comprehensive and cost effective countermeasure approach to enhance sensorimotor capabilities following long-duration space flight.
Mulavara, Ajitkumar; Kofman, Igor; DeDios, Yiri E.; Galvan, Raquel; Miller, Chris; Peters, Brian; Cohen, Helen; Jeevarajan, Jerome; Reschke, Millard; Wood, Scott; Bloomberg, Jacob
Basic polyamino acids rich in arginine, lysine, or ornithine cause both enhancement of and refractoriness to formation of endothelium-derived nitric oxide in pulmonary artery and vein.
The objective of this study was to elucidate the mechanism by which polyamino acids containing L-arginine, L-lysine or L-ornithine cause endothelium-dependent relaxation of bovine intrapulmonary artery and vein. Basic but not acidic or neutral polypeptides ranging in average molecular weights from 17 to 225 kDa elicited time- and concentration-dependent relaxation and cyclic GMP accumulation in precontracted rings of artery and vein by endothelium-dependent mechanisms. Vascular responses were markedly inhibited by oxyhemoglobin, methylene blue, or potassium. The basic polyamino acids stimulated the formation and/or release of an endothelium-derived relaxing factor (EDRF) identified as nitric oxide (NO) in perfused segments of both artery and vein as assessed by bioassay. The polyamino acids and A23187 released a similar endothelium-derived NO (EDNO) from artery and vein, as assessed by the similar half-life (3-5 seconds), antagonism by superoxide anion or oxyhemoglobin, enhancement by superoxide dismutase, and lack of influence by indomethacin. The basic polyamino acids elicited potent relaxant responses with EC50 values ranging from 3 x 10(-9) to 2 x 10(-7) M, and a direct correlation was obtained between molecular weight and relaxation potency irrespective of the basic amino acid incorporated. Prolonged contact of arterial or venous rings with basic polyamino acids resulted in the rapid development of marked refractoriness to relaxation and cyclic GMP formation on addition of polyamino acid. Moreover, refractoriness developed to the vascular responses of other endothelium-dependent vasodilators but not to glyceryl trinitrate or isoproterenol. The mechanism of refractory responses was attributed to interference with EDNO formation and release as assessed by bioassay and chemical assay. The hypothesis is forwarded that the basic polyamino acids serve as partial substrates for the enzyme system that catalyzes the conversion of L-arginine to NO. Prolonged contact between substrate and enzyme results in enzyme desensitization and the development of refractoriness or a form of tolerance to vasodilators whose action is mediated by EDNO. PMID:2492213
Ignarro, L J; Gold, M E; Buga, G M; Byrns, R E; Wood, K S; Chaudhuri, G; Frank, G
Determination of time-course change rate for arterial xenon using the time course of tissue xenon concentration in xenon-enhanced computed tomography
In calculating tissue blood flow (TBF) according to the Fick principle, time-course information on arterial tracer concentration is indispensable and has a considerable influence on the accuracy of calculated TBF. In TBF measurement by xenon-enhanced computed tomography (Xe-CT), nonradioactive xenon gas is administered by inhalation as a tracer, and end-tidal xenon is used as a substitute for arterial xenon. There has been the assumption that the time-course change rate for end-tidal xenon concentration (Ke) and that for arterial xenon concentration (Ka) are substantially equal. Respiratory gas sampling is noninvasive to the patient and Ke can be easily measured by exponential curve fitting to end-tidal xenon concentrations. However, it is pointed out that there would be a large difference between Ke and Ka in many cases. The purpose of this work was to develop a method of determining the Ka value using the time course of tissue xenon concentration in Xe-CT. The authors incorporated Ka into the Kety autoradiographic equation as a parameter to be solved, and developed a method of least-squares to obtain the solution for Ka from the time-course changes in xenon concentration in the tissue. The authors applied this method of least-squares to the data from Xe-CT abdominal studies performed on 17 patients; the solution for Ka was found pixel by pixel in the spleen, and its Ka map was created for each patient. On the one hand, the authors obtained the average value of the Ka map of the spleen as the calculated Ka (Ka{sub calc}) for each patient. On the other hand, the authors measured Ka (Ka{sub meas}) using the time-course changes in CT enhancement in the abdominal aorta for each patient. There was a good correlation between Ka{sub calc} and Ka{sub meas} (r=0.966, P<0.0001), and these two Ka values were close to each other (Ka{sub calc}=0.935xKa{sub meas}+0.089). This demonstrates that Ka{sub calc} would be close to the true Ka value. Accuracy of TBF by Xe-CT can be improved with use of the average value of the Ka map of an organ like the spleen that has a single blood supply (only arterial inflow)
Sase, Shigeru; Takahashi, Hideaki; Ikeda, Hiroki; Kobayashi, Minoru; Matsumoto, Nobuyuki; Suzuki, Michihiro [Anzai Medical Co., Ltd., 3-9-15 Nishi-Shinagawa, Shinagawa-ku, Tokyo 141-0033 (Japan); Department of Internal Medicine, Division of Gastroenterology and Hepatology, School of Medicine, St. Marianna University, 2-16-1 Miyamae-ku, Sugao, Kawasaki 216-5811 (Japan)
Enhanced relationship between the tropical Atlantic SST and the summertime western North Pacific subtropical high after the early 1980s
NASA Astrophysics Data System (ADS)
western North Pacific subtropical high (WNPSH) in boreal summer shows a remarkable enhancement after the early 1980s. Whereas the sea surface temperature (SST) in the North Indian Ocean (NIO) and the equatorial eastern Pacific had been noted to have remarkable local or remote effects on enhancing the WNPSH, the influence of the Atlantic SST, so far, is hardly explored. This article reports a new finding: enhanced relationship between the tropical Atlantic (TA)-SST and the WNPSH after the early 1980s. Regression study suggests that the warm TA-SST produced a zonally overturning circulation anomaly, with descending over the equatorial central Pacific and ascending over the tropical Atlantic/eastern Pacific. The anomalous descending over the equatorial central Pacific likely induced low-level anticyclonic anomaly to the west and therefore enhanced the WNPSH. One implication of this new finding is for predictability. The well-known "spring predictability barrier" (i.e., the influence of El Nińo-Southern Oscillation (ENSO) falls dramatically during boreal spring) does not apply to the TA-SST/WNPSH relationship. The TA-SST shows consistently high correlation starting from boreal spring when the ENSO influence continues declining. The TA-SST extends the predictability of the WNPSH in boreal summer approximately one season earlier to boreal spring.
Hong, Chi-Cherng; Chang, Tao-Chi; Hsu, Huang-Hsiung
Chronic hypoxia-induced upregulation of Ca2+-activated Cl? channel in pulmonary arterial myocytes: a mechanism contributing to enhanced vasoreactivity
Chronic hypoxic pulmonary hypertension (CHPH) is associated with altered expression and function of cation channels in pulmonary arterial smooth muscle cells (PASMCs), but little is known for anion channels. The Ca2+-activated Cl? channel (CaCC), recently identified as TMEM16A, plays important roles in pulmonary vascular function. The present study sought to determine the effects of chronic hypoxia (CH) on the expression and function of CaCCs in PASMCs, and their contributions to the vascular hyperreactivity in CHPH. Male Wistar rats were exposed to room air or 10% O2 for 3–4 weeks to generate CHPH. CaCC current (ICl.Ca) elicited by caffeine-induced Ca2+ release or by depolarization at a constant high [Ca2+]i (500 or 750 nm) was significantly larger in PASMCs of CH rats compared to controls. The enhanced ICl.Ca density in CH PASMCs was unrelated to changes in amplitude of Ca2+ release, Ca2+-dependent activation, voltage-dependent properties or calcineurin-dependent modulation of CaCCs, but was associated with increased TMEM16A mRNA and protein expression. Maximal contraction induced by serotonin, an important mediator of CHPH, was potentiated in endothelium-denuded pulmonary arteries of CH rats. The enhanced contractile response was prevented by the CaCC blockers niflumic acid and T16Ainh-A01, or by the L-type Ca2+ channel antagonist nifedipine. The effects of niflumic acid and nifedipine were non-additive. Our results demonstrate for the first time that CH increases ICl.Ca density, which is attributable to an upregulation of TMEM16A expression in PASMCs. The augmented CaCC activity in PASMCs may potentiate membrane depolarization and L-type channel activation in response to vasoconstrictors and enhance pulmonary vasoreactivity in CHPH.
Sun, Hui; Xia, Yang; Paudel, Omkar; Yang, Xiao-Ru; Sham, James S K
Chronic hypoxia-induced upregulation of Ca2+-activated Cl- channel in pulmonary arterial myocytes: a mechanism contributing to enhanced vasoreactivity.
Chronic hypoxic pulmonary hypertension (CHPH) is associated with altered expression and function of cation channels in pulmonary arterial smooth muscle cells (PASMCs), but little is known for anion channels. The Ca(2+)-activated Cl(-) channel (CaCC), recently identified as TMEM16A, plays important roles in pulmonary vascular function. The present study sought to determine the effects of chronic hypoxia (CH) on the expression and function of CaCCs in PASMCs, and their contributions to the vascular hyperreactivity in CHPH. Male Wistar rats were exposed to room air or 10% O(2) for 3–4 weeks to generate CHPH. CaCC current (I(CI.Ca)) elicited by caffeine-induced Ca(2+) release or by depolarization at a constant high [Ca(2+)](i) (500 or 750 nm) was significantly larger in PASMCs of CH rats compared to controls. The enhanced I(CI.Ca)) density in CH PASMCs was unrelated to changes in amplitude of Ca(2+) release, Ca(2+)-dependent activation, voltage-dependent properties or calcineurin-dependent modulation of CaCCs, but was associated with increased TMEM16A mRNA and protein expression. Maximal contraction induced by serotonin, an important mediator of CHPH, was potentiated in endothelium-denuded pulmonary arteries of CH rats. The enhanced contractile response was prevented by the CaCC blockers niflumic acid and T16A(inh)-A01, or by the L-type Ca(2+) channel antagonist nifedipine. The effects of niflumic acid and nifedipine were non-additive. Our results demonstrate for the first time that CH increases I(CI.Ca) density, which is attributable to an upregulation of TMEM16A expression in PASMCs. The augmented CaCC activity in PASMCs may potentiate membrane depolarization and L-type channel activation in response to vasoconstrictors and enhance pulmonary vasoreactivity in CHPH. PMID:22674716
Sun, Hui; Xia, Yang; Paudel, Omkar; Yang, Xiao-Ru; Sham, James S K
Enhancing Drought Early Warning System for Sustainable Water Resources and Agricultural Management through Apllication of Space Science - Nigeria in Perspective
NASA Astrophysics Data System (ADS)
Enhancing Drought Early Warning System for Sustainable Water Resources and Agriculture Management through Application of Space Science - Nigeria in Perspective BY J N Okpara L E Akeh Anuforom P B Aribo and S O Olayanju Directorate of Applied Meteorological Services Nigerian Meteorological Agency NIMET P M B 615 Garki Abuja Nigeria e-mail underline Juddy Okpara yahoo co uk and underline tonycanuforom yahoo com underline Abstract This paper attempts to highlight the importance of drought early warning system in water resources and agricultural management in Nigeria Various studies have shown that the negative impacts of droughts and other forms of extreme weather phenomena can be substantially reduced by providing early warning on any impending weather extremes X-rayed in this study are the various techniques presently used by the Nigerian Meteorological Agency NIMET in generating information for meteorological Early Warning System EWS which are based on models that make use of ground-based raingauge data and sea surface temperatures SST Komuscu standardized precipitation index SPI inclusive These methods are often limited by such factors as network density of stations limited communication infrastructure human inefficiency etc NIMET is therefore embarking on the development of a new Satellite Agrometeorological Information System SAMIS-Nigeria for famine and drought early warning The system combines satellite data with raingauge data to give a range of
Okpara, J. N.; Akeh, L. E.; Anuforom, A. C.; Aribo, P. B.; Olayanju, S. O.
Early outcomes in the elderly: a meta-analysis of 4921 patients undergoing coronary artery bypass grafting--comparison between off-pump and on-pump techniques
Objective To assess early outcomes in the elderly population undergoing coronary revascularisation with and without cardiopulmonary bypass (CPB). Methods Meta?analysis of all retrospective, non?randomised studies comparing off?pump coronary artery bypass (OPCAB) versus CPB techniques in the elderly (>?70 years) between 1999 and 2005. Age?related early outcomes of interest were death, stroke, atrial fibrillation (AF), renal failure and length of stay in hospital. The random effects model was used. Sensitivity and heterogeneity were analysed. Results Analysis of 14 non?randomised studies comprising 4921 patients (OPCAB, 1533 (31.1%) and CPB, 3388 (68.9%)) showed a significantly lower incidence of death in the OPCAB group (odds ratio (OR) 0.48, 95% CI 0.28 to 0.84). This effect was greater in OPCAB octogenarians (OR 0.26, 95% CI 0.12 to 0.57). The pattern of incidence of stroke among the OPCAB octogenarians (OR 0.19, 95% CI 0.07 to 0.56) was similar. The incidence of AF was lower in the OPCAB group (OR 0.77, 95% CI 0.61 to 0.97). The incidence of renal failure did not differ. Length of hospital stay was shorter in the OPCAB group, although with significant heterogeneity. Conclusions OPCAB may be associated with lower incidence of death, stroke and AF in the elderly, which may result in shorter length of hospital stay. A large randomised trial would confirm whether the elderly would benefit more from OPCAB surgery.
Panesar, S S; Athanasiou, T; Nair, S; Rao, C; Jones, C; Nicolaou, M; Darzi, A
Acute helminth infection enhances early macrophage mediated control of mycobacterial infection.
Co-infection with mycobacteria and helminths is widespread in developing countries, but how this alters host immunological control of each pathogen is not comprehensively understood. In this study, we demonstrate that acute Nippostrongylus brasiliensis (Nb) murine infection reduce early pulmonary mycobacterial colonization. This Nb-associated reduction in pulmonary Mycobacterium tuberculosis colony-forming units was associated with early and increased activation of pulmonary CD4 T cells and increased T helper type 1 (Th1) and Th2 cytokine secretion. An accelerated and transient augmentation of neutrophils and alveolar macrophages (AMs) was also observed in co-infected animals. AMs displayed markers of both classical and alternative activation. Intranasal transfer of pulmonary macrophages obtained from donor mice 5 days after Nb infection significantly reduced pulmonary Mycobacterium bovis Bacille Calmette-Guérin clearance in recipient mice. These data demonstrate that early stage Nb infection elicits a macrophage response, which is protective during the early stages of subsequent mycobacterial infection. PMID:23250274
du Plessis, N; Kleynhans, L; Thiart, L; van Helden, P D; Brombacher, F; Horsnell, W G C; Walzl, G
Arterial Baroreflex Control of Cardiac Vagal Outflow in Older Individuals Can Be Enhanced by Aerobic Exercise Training
Maintained cardiac vagal function is critical to cardiovascular health in human aging. Aerobic exercise training has been thought an attractive intervention to increase cardiovagal baroreflex function however, the data are equivocal. Moreover, if regular exercise does reverse the age-related decline in cardiovagal baroreflex function, it is unknown how this might be achieved. Therefore, we assessed the effects of a 6-month aerobic training program on baroreflex gain and its mechanical and neural components in older individuals (5 women and 7 men, aged 55–71 years). We assessed baroreflex function using pharmacologic pressure changes (bolus nitroprusside followed by bolus phenylephrine) and estimated the integrated gain (?R-R interval/?systolic blood pressure) and mechanical (? diameter/? pressure) and neural (?R-R interval/? diameter) components via measurements of carotid artery diameter in previously sedentary older individuals before and after 6-months of aerobic training. There was a significant 26% increase in baroreflex gain that was directly related to the amount of exercise performed and that derived mainly from an increase in the neural component of the arterial baroreflex (p<0.05). We did find changes in the mechanical component but unlike integrated gain and the neural component, these were not related to the magnitude of the exercise stimulus. These results suggest that exercise training can have a powerful effect on cardiovagal baroreflex function, but a sufficient stimulus is necessary to produce the effect. Moreover, adaptations in the afferent efferent baroreflex control of cardiac vagal outflow may be crucial for the improvement in arterial baroreflex function in older humans.
Deley, Gaelle; Picard, Glen; Taylor, J. Andrew
Contrast enhanced MRI characterization of the perfusion territories fed by individual coronary arteries in ex-vivo porcine heart
NASA Astrophysics Data System (ADS)
Sudden cardiac death is often caused by ventricular arrhythmias. These arrhythmias are believed to originate from the border zones where tissue was damaged by an ischemic event involving the coronary arteries. The specific mechanisms relating the geometry of these territories to the electrical behavior remains poorly understood. A major problem is the lack of detailed information describing the morphology of the affected perfusion bed. We present the first perfusion MR images of excised whole heart preparations where the irregular boundaries of perfusion territories are described. The filling pattern and final volume of the RCA perfusion territory are clearly visualized.
Szeverenyi, Nikolaus M.; Searles, Bruce; Pertsov, Arkady
The Enhancer Landscape during Early Neocortical Development Reveals Patterns of Dense Regulation and Co-option
Genetic studies have identified a core set of transcription factors and target genes that control the development of the neocortex, the region of the human brain responsible for higher cognition. The specific regulatory interactions between these factors, many key upstream and downstream genes, and the enhancers that mediate all these interactions remain mostly uncharacterized. We perform p300 ChIP-seq to identify over 6,600 candidate enhancers active in the dorsal cerebral wall of embryonic day 14.5 (E14.5) mice. Over 95% of the peaks we measure are conserved to human. Eight of ten (80%) candidates tested using mouse transgenesis drive activity in restricted laminar patterns within the neocortex. GREAT based computational analysis reveals highly significant correlation with genes expressed at E14.5 in key areas for neocortex development, and allows the grouping of enhancers by known biological functions and pathways for further studies. We find that multiple genes are flanked by dozens of candidate enhancers each, including well-known key neocortical genes as well as suspected and novel genes. Nearly a quarter of our candidate enhancers are conserved well beyond mammals. Human and zebrafish regions orthologous to our candidate enhancers are shown to most often function in other aspects of central nervous system development. Finally, we find strong evidence that specific interspersed repeat families have contributed potentially key developmental enhancers via co-option. Our analysis expands the methodologies available for extracting the richness of information found in genome-wide functional maps.
Chung, Tisha; Tuteja, Geetu; Guturu, Harendra; Schaar, Bruce T.; Bejerano, Gill
Assessing the end-organ in peripheral arterial occlusive disease--from contrast--enhanced ultrasound to blood-oxygen-level-dependent MR imaging
Peripheral arterial occlusive disease (PAOD) is a result of atherosclerotic disease which is currently the leading cause of morbidity and mortality in the western world. Patients with PAOD may present with intermittent claudication or symptoms related to critical limb ischemia. PAOD is associated with increased mortality rates. Stenoses and occlusions are usually detected by macrovascular imaging, including ultrasound and cross-sectional methods. From a pathophysiological view these stenoses and occlusions are affecting the microperfusion in the functional end-organs, such as the skin and skeletal muscle. In the clinical arena new imaging technologies enable the evaluation of the microvasculature. Two technologies currently under investigation for this purpose on the end-organ level in PAOD patients are contrast-enhanced ultrasound (CEUS) and blood-oxygen-level-dependent (BOLD) MR imaging (MRI). The following article is providing an overview about these evolving techniques with a specific focus on skeletal muscle microvasculature imaging in PAOD patients.
Partovi, Sasan; Jacobi, Bjoern; Fergus, Nathan; Schulte, Anja-Carina; Robbin, Mark R.; Bilecen, Deniz; Staub, Daniel
3T Dynamic Contrast Enhanced Magnetic Resonance Imaging in Prostate Cancer -- Comparison between Population-Averaged and Patient Specific Arterial Input Function
NASA Astrophysics Data System (ADS)
A population-averaged bi-exponential Arterial Input Function (AIF) has been commonly used to fit Dynamic Contrast Enhanced (DCE) MRI data to pharmacokinetic models. It has also been shown that patient specific AIF improves fit of prostate DCE MRI data to an adiabatic approximation model. In this pilot study, we compared the quality of fit of prostate DCE MRI data (acquired at 3T from two patients) to extended Kety model using the population-averaged AIF and patient specific AIF. Physiological parameters (K^trans--volume transfer constant, ve--extra-cellular extra-vascular space and vp--blood plasma volume) were calculated from tumor, peripheral zone and central gland of prostate. By comparing ?^2 of the fit with the two AIFs of a high enhancing voxel, we conclude that patient specific AIF provides more accurate pharmacokinetic modeling of prostate DCE MRI data in high enhancing areas than population-averaged AIF, thus patient specific AIF may result in more accurate detection of prostatic carcinoma.
Meng, Ran; Maedler, Burkhard; Chang, Silvia; Jones, Edward; Goldenberg, Larry; Kozlowski, Piotr
Right ventricle-to-pulmonary artery shunt versus modified Blalock-Taussig shunt in the Norwood procedure for hypoplastic left heart syndrome – influence on early and late haemodynamic status
Objective: The aim of this study was to assess changes in early and late haemodynamic status after the Norwood procedure (NP), caused by the implementation of right ventricle-to-pulmonary artery shunt (RV-PA). Methods: A consecutive series of 68 children with hypoplastic left heart syndrome underwent NP: Group 1 (n=31) with the application of a modified Blalock-Taussig shunt and Group 2 (n=37)
Edward Malec; Katarzyna Januszewska; Jacek Kolcz; Tomasz Mroczek
Vasodilator responses of rat isolated tail artery enhanced by oxygen- dependent, photochemical release of nitric oxide from iron-sulphur-nitrosyls.
1. The vasodilator properties and photochemical decomposition of two synthetic iron-sulphur-nitrosyl clusters (cluster A: [Fe4S4(NO)4], tetranitrosyl-tetra-mu 3-sulphido-tetrahedro-tetrairon; and B:[Fe4S3 (NO)7]-1, heptanitrosyl-tri-mu 3-thioxotetraferrate(-1)) have been investigated. Experiments were carried out on isolated, internally-perfused segments of rat tail artery. 2. Bolus injections (10 microliters) of A or B ( > 0.25 mM) delivered into the internal perfusate generated sustained (or S-type) vasodilator responses, characterized by a persistent plateau of reduced tone due to NO released from clusters which enter and become trapped within endothelial cells. Clusters were therefore irradiated with visible laser light (lambda = 457.9 or 514.5 nm) either (a) in solution, while passing through a glass tube en route to the artery; or (b) when retained within the endothelium, by illuminating the artery directly during the plateau of an S-type response. Irradiation produced an additional vasodilator response, the magnitude of which depended upon wavelength and laser beam energy. 3. The nitric oxide synthase inhibitor, NG-monomethyl-L-arginine (100 microM), had no effect on light-induced vasodilator responses. However, they were (a) blocked entirely by adding oxyhaemoglobin (5 microM) to the internal perfusate; and (b) greatly enhanced by the enzyme superoxide dismutase (150 u ml-1). 4. Photolysis of cluster B was measured by absorption spectroscopy and by detecting NO released with an electrochemical sensor. The photochemical reaction was found to be oxygen-dependent. The half-time for inactivation of cluster-derived NO was measured by interposing different lengths of tubing (i.e. time delays) between the photolysis tube and NO sensor. The steady-state probe current decayed exponentially with increasing delay time, with a t 1/2 of 21 s. The amplitudes of vasodilator responses of the tail artery also decreased exponentially by increasing the time delay (t 1/2 = 58 s). Superoxide dismutase (150 u ml-1) prevented this from happening, showing that "inactivation' of cluster-derived NO was caused by reaction with superoxide anions formed during photolysis. 5. We conclude that potentiation of vasodilator responses to iron-sulphur-nitrosyl clusters by visible light is due to an oxygen-dependent photochemical reaction which accelerates the release of ligated nitrosyl groups as free NO. Based on our measurements, we estimate that ca 100 pM NO is sufficient to produce a just-detectable additional vasodilatation and that the ED50 dose is ca 3.7 nM.
Flitney, F. W.; Megson, I. L.; Thomson, J. L.; Kennovin, G. D.; Butler, A. R.
Vasodilator responses of rat isolated tail artery enhanced by oxygen- dependent, photochemical release of nitric oxide from iron-sulphur-nitrosyls.
1. The vasodilator properties and photochemical decomposition of two synthetic iron-sulphur-nitrosyl clusters (cluster A: [Fe4S4(NO)4], tetranitrosyl-tetra-mu 3-sulphido-tetrahedro-tetrairon; and B:[Fe4S3 (NO)7]-1, heptanitrosyl-tri-mu 3-thioxotetraferrate(-1)) have been investigated. Experiments were carried out on isolated, internally-perfused segments of rat tail artery. 2. Bolus injections (10 microliters) of A or B ( > 0.25 mM) delivered into the internal perfusate generated sustained (or S-type) vasodilator responses, characterized by a persistent plateau of reduced tone due to NO released from clusters which enter and become trapped within endothelial cells. Clusters were therefore irradiated with visible laser light (lambda = 457.9 or 514.5 nm) either (a) in solution, while passing through a glass tube en route to the artery; or (b) when retained within the endothelium, by illuminating the artery directly during the plateau of an S-type response. Irradiation produced an additional vasodilator response, the magnitude of which depended upon wavelength and laser beam energy. 3. The nitric oxide synthase inhibitor, NG-monomethyl-L-arginine (100 microM), had no effect on light-induced vasodilator responses. However, they were (a) blocked entirely by adding oxyhaemoglobin (5 microM) to the internal perfusate; and (b) greatly enhanced by the enzyme superoxide dismutase (150 u ml-1). 4. Photolysis of cluster B was measured by absorption spectroscopy and by detecting NO released with an electrochemical sensor. The photochemical reaction was found to be oxygen-dependent. The half-time for inactivation of cluster-derived NO was measured by interposing different lengths of tubing (i.e. time delays) between the photolysis tube and NO sensor. The steady-state probe current decayed exponentially with increasing delay time, with a t 1/2 of 21 s. The amplitudes of vasodilator responses of the tail artery also decreased exponentially by increasing the time delay (t 1/2 = 58 s). Superoxide dismutase (150 u ml-1) prevented this from happening, showing that "inactivation' of cluster-derived NO was caused by reaction with superoxide anions formed during photolysis. 5. We conclude that potentiation of vasodilator responses to iron-sulphur-nitrosyl clusters by visible light is due to an oxygen-dependent photochemical reaction which accelerates the release of ligated nitrosyl groups as free NO. Based on our measurements, we estimate that ca 100 pM NO is sufficient to produce a just-detectable additional vasodilatation and that the ED50 dose is ca 3.7 nM. PMID:8730753
Flitney, F W; Megson, I L; Thomson, J L; Kennovin, G D; Butler, A R
Angiotensin II enhances AT1-Nox1 binding and stimulates arterial smooth muscle cell migration and proliferation through AT1, Nox1, and interleukin-18.
The redox-sensitive transcription factors NF-?B and activator protein-1 (AP-1) are critical mediators of ANG II signaling. The promitogenic and promigratory factor interleukin (IL)-18 is an NF-?B- and AP-1-responsive gene. Therefore, we investigated whether ANG II-mediated smooth muscle cell (SMC) migration and proliferation involve IL-18. ANG II induced rat carotid artery SMC migration and proliferation and IL-18 and metalloproteinase (MMP)-9 expression via ANG II type 1 (AT(1)) receptor. ANG II-induced superoxide generation, NF-?B and AP-1 activation, and IL-18 and MMP-9 induction were all markedly attenuated by losartan, diphenyleneiodonium chloride (DPI), and Nox1 knockdown. Similar to ANG II, addition of IL-18 also induced superoxide generation, activated NF-?B and AP-1, and stimulated SMC migration and proliferation, in part via Nox1, and both ANG II and IL-18 induced NOX1 transcription in an AP-1-dependent manner. AT(1) physically associates with Nox1 in SMC, and ANG II enhanced this binding. Interestingly, exogenous IL-18 neither induced AT(1) binding to Nox1 nor enhanced the ANG II-induced increase in AT(1)/Nox1 binding. Importantly, IL-18 knockdown, or pretreatment with IL-18 neutralizing antibodies, or IL-18 binding protein, all attenuated the migratory and mitogenic effects of ANG II. Continuous infusion of ANG II for 7 days induced carotid artery hyperplasia in rats via AT(1) and was associated with increased AT(1)/Nox1 binding (despite lower AT(1) levels); increased DPI-inhibitable superoxide production; increased phospho-IKK?, JNK, p65, and c-Jun; and induction of IL-18 and MMP-9 in endothelium-denuded carotid arteries. These results indicate that IL-18 amplifies the ANG II-induced, redox-dependent inflammatory cascades by activating similar promitogenic and promigratory signal transduction pathways. The ANG II/Nox1/IL-18 pathway may be critical in hyperplastic vascular diseases, including atherosclerosis and restenosis. PMID:22636674
Valente, Anthony J; Yoshida, Tadashi; Murthy, Subramanyam N; Sakamuri, Siva S V P; Katsuyama, Masato; Clark, Robert A; Delafontaine, Patrice; Chandrasekar, Bysani
A Pathway to Enhancing Professionalism: Building a Bridge between TAFE and University Early Childhood Qualifications
ERIC Educational Resources Information Center
It has been argued that a key strategy to improve developmental and educational outcomes for young children is to increase the number of childcare staff with early childhood university degrees (Saracho & Spodek, 2007). In order to upgrade the qualifications of staff, a number of Australian universities provide pathways that enable graduates of…
Whitington, Victoria; Ebbeck, Marjory; Diamond, Alexandra; Yim, Hoi Yin Bonnie
Enhanced biodiversity in the deep: Early Pleistocene coral communities from southern Italy
The Early Pleistocene fault plane of Furnari, that outcrops in northeastern Sicily (southern Italy), provided a primary hard substrate for the settling and growth of large coral colonies. Even though the corals did not form frameworks, they influenced the composition and distribution of the benthic communities. Corals and associated fauna produced organogenic debris, which was deposited along the fault scarp,
Italo Di Geronimo; Carlo Messina; Antonietta Rosso; Rossana Sanfilippo; Francesco Sciuto; Agostina Vertino
The Transition Process in the Early Years: Enhancing Speech-Language Pathologists' Perspectives.
ERIC Educational Resources Information Center
This article provides information from a speech-language perspective pertaining to transitions in the early years, especially between preschool settings and kindergarten. It highlights challenges in transition and delineates critical components of transition planning including family-school partnerships, collaboration, and written policies and…
Prendeville, Jo-Anne; Ross-Allen, Jane
Use of Cameras in an Early Childhood Classroom to Enhance Academic and Self-Concept Growth.
National Technical Information Service (NTIS)
This report of a study which explored the effects of camera use among 30 children in a biracial multi-aged classroom includes suggestions for the application of the findings in early childhood curriculum. The first two chapters present the purpose, ration...
B. New
Enhancing Language and Early Literacy Development of Lowest Performing Preschoolers: Yes We Can!
ERIC Educational Resources Information Center
This discussion article takes a closer look at 5 Early Reading First projects in this special issue. It first explores what needed to be in place before these projects could help teachers individualize instructional support for children. The way in which each project sought to provide effective instruction for all children is then discussed,…
Marcon, Rebecca A.
Enhancing Language and Early Literacy Development of Lowest Performing Preschoolers: Yes We Can!
This discussion article takes a closer look at 5 Early Reading First projects in this special issue. It first explores what needed to be in place before these projects could help teachers individualize instructional support for children. The way in which each project sought to provide effective instruction for all children is then discussed, followed by demonstrated project outcomes. The
Rebecca A. Marcon
Enhancing Early Numeracy by Promoting the Abstract Thought Involved in the Oddity Principle, Seriation, and Conservation
ERIC Educational Resources Information Center
Although many students who enter kindergarten are cognitively ready to meet the demands of the kindergarten mathematics curriculum, some students arrive without the early abstract reasoning abilities necessary to benefit from the instruction provided. Those who do not possess key cognitive abilities, including understandings of conservation,…
Kidd, Julie K.; Pasnak, Robert; Gadzichowski, Marinka; Ferral-Like, Melissa; Gallington, Debbie
Do reaction time measures enhance diagnosis of early-stage dementia of the Alzheimer type
Reaction times (RT) typically are slower in demented individuals than in healthy older people, but it is unclear if this deficit is useful in diagnosing Alzheimer's disease, particularly in its early stages. In this study we compared 131 nondemented, 73 very mildly demented, and 45 mildly demented individuals on simple, choice, and choice with distraction RT tasks. Less than half
Martha Storandt; Sherry Beaudreau
Otx2 and Oct4 Drive Early Enhancer Activation during Embryonic Stem Cell Transition from Naive Pluripotency
Summary Embryonic stem cells (ESCs) are unique in that they have the capacity to differentiate into all of the cell types in the body. We know a lot about the complex transcriptional control circuits that maintain the naive pluripotent state under self-renewing conditions but comparatively less about how cells exit from this state in response to differentiation stimuli. Here, we examined the role of Otx2 in this process in mouse ESCs and demonstrate that it plays a leading role in remodeling the gene regulatory networks as cells exit from ground state pluripotency. Otx2 drives enhancer activation through affecting chromatin marks and the activity of associated genes. Mechanistically, Oct4 is required for Otx2 expression, and reciprocally, Otx2 is required for efficient Oct4 recruitment to many enhancer regions. Therefore, the Oct4-Otx2 regulatory axis actively establishes a new regulatory chromatin landscape during the early events that accompany exit from ground state pluripotency.
Yang, Shen-Hsi; Kalkan, Tuzer; Morissroe, Claire; Marks, Hendrik; Stunnenberg, Hendrik; Smith, Austin; Sharrocks, Andrew D.
Otx2 and Oct4 Drive Early Enhancer Activation during Embryonic Stem Cell Transition from Naive Pluripotency.
Embryonic stem cells (ESCs) are unique in that they have the capacity to differentiate into all of the cell types in the body. We know a lot about the complex transcriptional control circuits that maintain the naive pluripotent state under self-renewing conditions but comparatively less about how cells exit from this state in response to differentiation stimuli. Here, we examined the role of Otx2 in this process in mouse ESCs and demonstrate that it plays a leading role in remodeling the gene regulatory networks as cells exit from ground state pluripotency. Otx2 drives enhancer activation through affecting chromatin marks and the activity of associated genes. Mechanistically, Oct4 is required for Otx2 expression, and reciprocally, Otx2 is required for efficient Oct4 recruitment to many enhancer regions. Therefore, the Oct4-Otx2 regulatory axis actively establishes a new regulatory chromatin landscape during the early events that accompany exit from ground state pluripotency. PMID:24931607
Yang, Shen-Hsi; Kalkan, Tüzer; Morissroe, Claire; Marks, Hendrik; Stunnenberg, Hendrik; Smith, Austin; Sharrocks, Andrew D
Comparative studies on mammalian Hoxc8 early enhancer sequence reveal a baleen whale-specific deletion of a cis-acting element
Variations in regulatory regions of developmental control genes have been implicated in the divergence of axial morphologies. To find potentially significant changes in cis-regulatory regions, we compared nucleotide sequences and activities of mammalian Hoxc8 early enhancers. The nucleotide sequence of the early enhancer region is extremely conserved among mammalian clades, with five previously described cis-acting elements, A–E, being invariant. However, a 4-bp deletion within element C of the Hoxc8 early enhancer sequence is observed in baleen whales. When assayed in transgenic mouse embryos, a baleen whale enhancer (unlike other mammalian enhancers) directs expression of the reporter gene to more posterior regions of the neural tube but fails to direct expression to posterior mesoderm. We suggest that regulation of Hoxc8 in baleen whales differs from other mammalian species and may be associated with variation in axial morphology.
Shashikant, Cooduvalli S.; Kim, Chang B.; Borbely, Marc A.; Wang, Wayne C. H.; Ruddle, Frank H.
Early accelerated senescence of circulating endothelial progenitor cells in premature coronary artery disease patients in a developing country - a case control study
Background The decreased number and senescence of circulating endothelial progenitor cells (EPCs) are considered markers of vascular senescence associated with aging, atherosclerosis, and coronary artery disease (CAD) in elderly. In this study, we explore the role of vascular senescence in premature CAD (PCAD) in a developing country by comparing the numerical status and senescence of circulating EPCs in PCAD patients to controls. Methods EPCs were measured by flow cytometry in 57 patients with angiographically documented CAD, and 57 controls without evidence of CAD, recruited from random patients???50 years of age at All India Institute of Medical Sciences. EPC senescence as determined by telomere length (EPC-TL) and telomerase activity (EPC-TA) was studied by real time polymerase chain reaction (q PCR) and PCR– ELISA respectively. Result The number of EPCs (0.18% Vs. 0.039% of total WBCs, p?0.0001), and EPC-TL (3.83 Vs. 5.10 kb/genome, p?=?0.009) were markedly lower in PCAD patients compared to controls. These differences persisted after adjustment for age, sex, BMI, smoking and medications. EPC-TA was reduced in PCAD patients, but was statistically significant only after adjustment for confounding factors (1.81 Vs. 2.20 IU/cell, unadjusted p?=?0.057, adjusted p?=?0.044). Conclusions We observed an association between increased vascular cell senescence with PCAD in a sample of young patients from India. This suggests that early accelerated vascular cell senescence may play an important mechanistic role in CAD epidemic in developing countries like India where PCAD burden is markedly higher compared to developed countries.
Glycosylated hemoglobin A1c as a marker predicting the severity of coronary artery disease and early outcome in patients with stable angina
Background Glycosylated hemoglobin A1C (HbA1c) has been widely recognized as a marker for predicting the severity of diabetes mellitus (DM) and several cardiovascular diseases. However, whether HbA1c could predict the severity and clinical outcomes in patients with stable coronary artery disease (CAD) remains largely unknown. We determine relationship of HbA1c with severity and outcome in patients with stable CAD. Methods We enrolled 1433 patients with stable angina who underwent coronary angiography and were followed up for an average 12 months. The patients were classified into three groups by tertiles of baseline HbA1c level (low group <5.7%, n?=?483; intermediate group 5.7 - 6.3%, n?=?512; high group >6.3%, n?=?438). The relationships between the plasma HbA1c and severity of CAD and early clinical outcomes were evaluated. Results High HbA1c was associated with three-vessel disease. Area under the receivers operating characteristic curve (AUC?=?0.67, 95% CI: 0.63-0.71, P?0.001) and multivariate logistic regression analysis suggested that HbA1C was an independent predictor of severity of CAD (OR?=?1.60, 95% CI: 1.29-1.99, P?0.001) even after adjusting for gender, age, risk factor of CAD, lipid profile and fasting blood glucose. During follow-up, 133 patients underwent pre-specified outcomes. After adjusting for multiple variables in the Cox regression model, HbA1C remained to be an independent predictor of poor prognosis (HR?=?1.28, 95% CI: 1.12-1.45, P?0.001). Conclusions We concluded that high level of baseline HbA1c appeared to be an independent predictor for the severity of CAD and poor outcome in patients with stable CAD.
Evidence to implicate early modulation of interleukin-1beta expression in the neuroprotection afforded by 17beta-estradiol in male rats undergone transient middle cerebral artery occlusion.
Neuroprotection exerted by 17beta-estradiol (17beta-E(2)) has been widely investigated in animal models of acute cerebral ischemia. Estrogens interact with intracellular receptors (ERalpha and ERbeta) to modulate the transcription of target genes, including those implicated in neuronal survival. Neuroprotection may also occur via interaction with ER-like membrane receptors mediating rapid, non-genomic, actions or via receptor-independent mechanisms. There is also evidence that blockade of inflammatory factors may represent an important mechanism involved in estrogenic neuroprotection. Here we investigate whether reduced brain damage by acute pharmacological treatment with 17beta-E(2) in male rats subjected to transient (2h) middle cerebral artery occlusion (tMCAo) involves modulation of interleukin-1beta (IL-1beta), a proinflammatory cytokine strongly implicated in the pathophysiology of ischemic stroke. Administration of 17beta-E(2) (0.2mg/kg, i.p., 1h before tMCAo) results in significant reduction of brain infarct volume, and this is reverted by the ER antagonist ICI 182,780 (0.25mg/kg, i.p.) administered 1h before 17beta-E(2). Two hours MCAo followed by 2-h reperfusion results in a significant, threefold increase of IL-1beta levels in the cortical tissue ipsilateral to the ischemic damage. Interestingly, a pretreatment with a neuroprotective dose of 17beta-E(2) attenuates the cytokine elevation and this appears to occur through ER activation. In addition, neuroprotection by 17beta-E(2) is accompanied by reduced cytochrome c translocation both in the striatum and in the cortex as revealed by Western blotting 3h after reperfusion. In conclusion, we report the original observation that neuroprotection exerted by 17beta-E(2) in a rat model of transient focal brain ischemia is accompanied by reduced cytochrome c translocation to the cytosol and involves early modulation of IL-1beta production. PMID:17678971
Chiappetta, Olga; Gliozzi, Micaela; Siviglia, Elisa; Amantea, Diana; Morrone, Luigi A; Berliocchi, Laura; Bagetta, G; Corasaniti, M Tiziana
Prematurely elevating estradiol in early baboon pregnancy suppresses uterine artery remodeling and expression of extravillous placental vascular endothelial growth factor and ?1?1 and ?5?1 integrins.
We previously showed that advancing the increase in estradiol levels from the second to the first third of baboon pregnancy suppressed placental extravillous trophoblast (EVT) invasion and remodeling of the uterine spiral arteries. Cell culture studies show that vascular endothelial cell growth factor (VEGF) plays a central role in regulating EVT migration and remodeling of the uterine spiral arteries by increasing the expression/action of certain integrins that control extracellular matrix remodeling. To test the hypothesis that the estradiol-induced reduction in vessel remodeling in baboons is associated with an alteration in VEGF and integrin expression, extravillous placental VEGF and integrin expression was determined on d 60 of gestation (term is 184 d) in baboons in which uterine artery transformation was suppressed by maternal estradiol administration on d 25-59. EVT uterine spiral artery invasion was 5-fold lower (P < 0.01), and VEGF protein expression, quantified by in situ proximity ligation assay, was 50% lower (P < 0.05) in the placenta anchoring villi of estradiol-treated than in untreated baboons. ?1?1 and ?5?1 mRNA levels in cells isolated by laser capture microdissection from the anchoring villi and cytotrophoblastic shell of estradiol-treated baboons were over 2-fold (P < 0.01) and 40% (P < 0.05) lower, respectively, than in untreated animals. In contrast, placental extravillous ?v?3 mRNA expression was unaltered by estradiol treatment. In summary, extravillous placental expression of VEGF and ?1?1 and ?5?1 integrins was decreased in a cell- and integrin-specific manner in baboons in which EVT invasion and remodeling of the uterine spiral arteries were suppressed by prematurely elevating estradiol levels in early pregnancy. We propose that estrogen normally controls the extent to which the uterine arteries are transformed by placental EVT in primate pregnancy by regulating expression of VEGF and particular integrin extracellular remodeling molecules that mediate this process. PMID:22495671
Bonagura, Thomas W; Babischkin, Jeffery S; Aberdeen, Graham W; Pepe, Gerald J; Albrecht, Eugene D
Coping in Young Children: Early Intervention Practices To Enhance Adaptive Behavior and Resilience.
ERIC Educational Resources Information Center
This book describes an intervention framework to help young children (birth to 36 months) who have or are at risk of having a disability, to cope more effectively. The book is written for an interdisciplinary audience including service providers, administrators, researchers, and policymakers. Emphasis is on enhancing the adaptive behavior and…
Zeitlin, Shirley; Williamson, G. Gordon
Enhanced Handling and Positioning in Early Infancy Advances Development throughout the First Year
ERIC Educational Resources Information Center
Behaviors emerge, in part, from the interplay of infant abilities and caregiver-infant interactions. Cross-cultural and developmental studies suggest caregiver handling and positioning influence infant development. In this prospective, longitudinal study, the effects of 3 weeks of enhanced handling and positioning experiences provided to 14…
Lobo, Michele A.; Galloway, James C.
Folic Acid Enhances Early Functional Recovery in a Piglet Model of Pediatric Head Injury
For stroke and spinal cord injury, folic acid supplementation has been shown to enhance neurodevelopment and to provide neuroprotection. We hypothesized that folic acid would reduce brain injury and improve neurological outcome in a neonatal piglet model of traumatic brain injury (TBI), using 4 experimental groups of 3- to 5-day-old female piglets. Two groups were intubated, anesthetized and had moderate
Maryam Y. Naim; Stuart Friess; Colin Smith; Jill Ralston; Karen Ryall; Mark A. Helfaer; Susan S. Margulies
Enhancing Alphabet Knowledge Instruction: Research Implications and Practical Strategies for Early Childhood Educators
ERIC Educational Resources Information Center
Alphabet knowledge is consistently recognized as the strongest, most durable predictor of later literacy achievement. Recent research offers practical implications for increased effectiveness of teaching alphabet knowledge to young children. In this article, we outline Enhanced Alphabet Knowledge instruction (EAK), a method of practical…
Jones, Cindy D.; Clark, Sarah K.; Reutzel, D. Ray
A Report on the Technological Enhancements Project Evaluation: Deepening Early Learning Experiences through Technology
ERIC Educational Resources Information Center
As part of the "Ready to Learn" Initiative, Education Development Center, Inc. (EDC), was charged with addressing the evaluation of Technological Enhancements for the outreach efforts of three producers: Out of the Blue's Super WHY! Technology Add-On; Sesame Workshop's The Electric Company School's Initiative Curriculum; and WordWorld's eBook…
Hupert, Naomi; Cervantes, Francisco; DeGroof, Emily
Difference between pre-operative and cardiopulmonary bypass mean arterial pressure is independently associated with early cardiac surgery-associated acute kidney injury
Background Cardiac surgery-associated acute kidney injury (CSA-AKI) contributes to increased morbidity and mortality. However, its pathophysiology remains incompletely understood. We hypothesized that intra-operative mean arterial pressure (MAP) relative to pre-operative MAP would be an important predisposing factor for CSA-AKI. Methods We performed a prospective observational study of 157 consecutive high-risk patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The primary exposure was delta MAP, defined as the pre-operative MAP minus average MAP during CPB. Secondary exposure was CPB flow. The primary outcome was early CSA-AKI, defined by a minimum RIFLE class - RISK. Univariate and multivariate logistic regression were performed to explore for association between delta MAP and CSA-AKI. Results Mean (± SD) age was 65.9 ± 14.7 years, 70.1% were male, 47.8% had isolated coronary bypass graft (CABG) surgery, 24.2% had isolated valve surgery and 16.6% had combined procedures. Mean (± SD) pre-operative, intra-operative and delta MAP were 86.6 ± 13.2, 57.4 ± 5.0 and 29.4 ± 13.5 mmHg, respectively. Sixty-five patients (41%) developed CSA-AKI within in the first 24 hours post surgery. By multivariate logistic regression, a delta MAP?26 mmHg (odds ratio [OR], 2.8; 95%CI, 1.3-6.1, p = 0.009) and CPB flow rate ?54 mL/kg/min (OR, 0.2, 0.1-0.5, p < 0.001) were independently associated with CSA-AKI. Additional variables associated with CSA-AKI included use of a side-biting aortic clamp (OR, 3.0; 1.3-7.1, p = 0.012), and body mass index ?25 (OR, 4.2; 1.6-11.2, p = 0.004). Conclusion A large delta MAP and lower CPB flow during cardiac surgery are independently associated with early post-operative CSA-AKI in high-risk patients. Delta MAP represents a potentially modifiable intra-operative factor for development of CSA-AKI that necessitates further inquiry.
Characterising a technology development at the stage of early emerging applications: nanomaterial-enhanced biosensors
We devise future-oriented technology analyses tools to investigate a technology at an interesting development stage of early emerging applications. At this stage, technologies show great potential with little established commercialisation. Future development pathways are highly uncertain and heavily dependent on contextual interactions. We apply R&D profiling, R&D-to-applications cross-charting, and technology delivery system modelling to help understand the phenomena that bear
Lu Huang; Ying Guo; Zhengchun Peng; Alan L. Porter
Climatic effects of enhanced CO2 levels in Mars early atmosphere
NASA Technical Reports Server (NTRS)
Results are presented of one-dimensional radiation convection modeling of the early Mars atmosphere. Up to 5 bars of CO2 would have been required to raise the surface temperature (orbitally and globally averaged) above the freezing point, although at the equator at perihelion, 1 bar would have sufficed. Such an atmospheric CO2 invertory, the author argued, is not inconsistent with any known constraint on Mars' degassed volatile inventory.
Kasting, James F.
Carbon-Enhanced Metal-Poor Stars in the Early Galaxy
NASA Astrophysics Data System (ADS)
Very metal-deficient stars that exhibit enhancements of their carbon abundances are of crucial importance for understanding a number of issues: The nature of stellar evolution among the first generations of stars, the shape of the Initial Mass Function, and the relationship between carbon enhancement and neutron-capture processes, in particular the astrophysical s-process. One fundamental result from recent objective-prism surveys dedicated to the discovery of metal-deficient stars is that the frequency, and perhaps, the level, of carbon enhancement increases greatly with declining metallicity. Most previous discoveries of these important stars have been serendipitous, as the stars were initially targeted because of their apparently low overall metallicity, and it was only discovered later that carbon was strongly enhanced. To more completely explore this phenemonon, we have undertaken spectroscopic follow-up of a published list of metal-deficient candidates from the Hamburg/ESO prism survey (Christlieb et al. 2001, A & A, 375, 366) that show clearly strong carbon features directly on the survey plates. We have obtained spectra for some 350 of the 413 stars in the sample, and will report on their observed properties, including estimates of their [Fe/H] and [C/Fe], their radial velocities, and their spatial distribution. Of particular importance, we find that the upper envelope of carbon enhancement observed for these stars is nearly constant, at [C/H] = -1.0, over the metallicity range -4.0 < [Fe/H] < -2.0 ; this same level of [C/H] applies to the most iron-deficent star yet discovered, HE 0107-5240. Implications of these results will be discussed. This work has received partial support from NSF grants AST 00-98508 and AST 00-98549. Support has also been received from FAPESP and CNPq (Brazil), the Deutsche Forschungsgemeinschaft (Re 353/44-1), the Australian Research Council (DP0342613), and PPARK (UK: PPA/O/S/1998/00658).
Marsteller, B.; Beers, T. C.; Rossi, S.; Sneden, C.; Christlieb, N.; Bessell, M.; Norris, J. E.; Rhee, J.; Ryan, S. G.
Contrast-Enhanced 2D Cine Phase MR Angiography for Measurement of Basilar Artery Blood Flow in Posterior Circulation Ischemia
BACKGROUND AND PURPOSE: Dizziness is a symptom that develops with internal ear disturbances and with dysfunctions of the brain stem and cerebellum, in particular with blood flow disturbances of the brain stem and cerebellum (posterior circulation ischemia (PCI)). Patients with PCI often present with various neurologic signs and symptoms. To examine the usefulness of contrast-enhanced 2D cine phase MR angiography
Takeshi Kato; Toshikatsu Indo; Eiji Yoshida; Yasushi Iwasaki; Mie Sone; Gen Sobue
High Calcium Bioglass Enhances Differentiation and Survival of Endothelial Progenitor Cells, Inducing Early Vascularization in Critical Size Bone Defects
Early vascularization is a prerequisite for successful bone healing and endothelial progenitor cells (EPC), seeded on appropriate biomaterials, can improve vascularization. The type of biomaterial influences EPC function with bioglass evoking a vascularizing response. In this study the influence of a composite biomaterial based on polylactic acid (PLA) and either 20 or 40% bioglass, BG20 and BG40, respectively, on the differentiation and survival of EPCs in vitro was investigated. Subsequently, the effect of the composite material on early vascularization in a rat calvarial critical size defect model with or without EPCs was evaluated. Human EPCs were cultured with ?-TCP, PLA, BG20 or BG40, and seeding efficacy, cell viability, cell morphology and apoptosis were analysed in vitro. BG40 released the most calcium, and improved endothelial differentiation and vitality best. This effect was mimicked by adding an equivalent amount of calcium to the medium and was diminished in the presence of the calcium chelator, EGTA. To analyze the effect of BG40 and EPCs in vivo, a 6-mm diameter critical size calvarial defect was created in rats (n?=?12). Controls (n?=?6) received BG40 and the treatment group (n?=?6) received BG40 seeded with 5×105 rat EPCs. Vascularization after 1 week was significantly improved when EPCs were seeded onto BG40, compared to implanting BG40 alone. This indicates that Ca2+ release improves EPC differentiation and is useful for enhanced early vascularization in critical size bone defects.
Nguyen Ngoc, Christina; Meier, Simon; Nau, Christoph; Schaible, Alexander; Marzi, Ingo; Henrich, Dirk
Contrast enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus
Objective To use contrast enhanced ultrasound (CEU) to quantify blood flow in the macaque uterus during early pregnancy. Design Prospective nonhuman primate study. Setting National Primate Research Center. Animals Naturally cycling female rhesus macaques (Macaca mulatta). Interventions Female macaques were mated on days 11–14 of the cycle. Females were then imaged by CEU and Doppler ultrasound (DUS) once every 3 days from day 21 through day 39 of the fertile cycle. Main Outcome Measures Visualization and quantification of uterine vascular perfusion. Results CEU identified the primary placental disc and underlying vessels ~2 days earlier than DUS was able to observe endometrial thickening. CEU revealed spatial differences in vascular perfusion between the endometrium, myometrium, and the endometrial-myometrial (junctional) zone. Myometrium displayed the highest rate of blood flow (>10 mL/min/g tissue). There was less blood flow in the endometrium and junctional zone (<3 mL/min/g). A brief fall in progesterone was observed during early implantation, which was correlated with reduced blood flow to all three uterine compartments, but did not reduce flow to the placenta. Conclusions CEU provides a sensitive, non-invasive method to assess vascular perfusion of the uterus during embryo implantation in macaques. We propose CEU as a new diagnostic tool to monitor vascular changes associated with early pregnancy in women.
Keator, Christopher S.; Lindner, Jonathan R.; Belcik, J. Todd; Bishop, Cecily V.; Slayden, Ov D.
Enhancing the Design Process for Complex Space Systems through Early Integration of Risk and Variable-Fidelity Modeling
NASA Technical Reports Server (NTRS)
An important enabler of the new national Vision for Space Exploration is the ability to rapidly and efficiently develop optimized concepts for the manifold future space missions that this effort calls for. The design of such complex systems requires a tight integration of all the engineering disciplines involved, in an environment that fosters interaction and collaboration. The research performed under this grant explored areas where the space systems design process can be enhanced: by integrating risk models into the early stages of the design process, and by including rapid-turnaround variable-fidelity tools for key disciplines. Enabling early assessment of mission risk will allow designers to perform trades between risk and design performance during the initial design space exploration. Entry into planetary atmospheres will require an increased emphasis of the critical disciplines of aero- and thermodynamics. This necessitates the pulling forward of EDL disciplinary expertise into the early stage of the design process. Radiation can have a large potential impact on overall mission designs, in particular for the planned nuclear-powered robotic missions under Project Prometheus and for long-duration manned missions to the Moon, Mars and beyond under Project Constellation. This requires that radiation and associated risk and hazards be assessed and mitigated at the earliest stages of the design process. Hence, RPS is another discipline needed to enhance the engineering competencies of conceptual design teams. Researchers collaborated closely with NASA experts in those disciplines, and in overall space systems design, at Langley Research Center and at the Jet Propulsion Laboratory. This report documents the results of this initial effort.
Mavris, Dimitri; Osburg, Jan
[Composite arterial conduits with internal thoracic artery and inferior epigastric artery for a myocardial revascularization].
From November 1992 to February 1995, 10 patients were submitted to myocardial revascularization using composite arterial conduit with internal thoracic artery (ITA) and inferior epigastric artery (IEA). The age ranged from 48 to 68 years (mean age, 60.3 years); all patients were male. All patients had double-or triple vessel disease. The mean ejection fraction was 61.8% (range, 43 to 77%). We used 28 arterial conduits including 5 right ITAs, 10 left ITAs, 10 IEAs, and 3 right gastroepiploic artery. 10 IEAs were anastomosed to one ITAs and 10 composite arterial conduits were constructed (branched in 3, lengthened in 7). In 5 patients a double ITAs were used in a single patient. There was no operative mortality and fetal complication. Early postoperative angiographic controls demonstrated 100% patency of composite grafts in 9 of 10 patients. The composite arterial graft using ITAs and IEAs is feasible and the anastomoses so performed are completely safe. PMID:7594842
Watanabe, G; Misaki, T; Kotoh, K; Yamashita, A; Nakajima, K; Fukahara, K; Ueyama, K
Enhancing the passing moments: An educational criticism of family visits to an early childhood science exhibition
NASA Astrophysics Data System (ADS)
This educational criticism describes and interprets the nature of family visits to an early childhood science exhibition, Working Wonders, at The Science Centre in Calgary, Alberta. The specific exhibits are described and features that contributed to exhibit popularity are examined. Examples of visitors' interactions with each exhibit are given. The visit experiences of four families are described in detail and analyzed. Typical family visitors' reactions, expectations, and experiences are summarized. Because one of the mutual expectations of the granting agency, The Science Centre, and the adult visitors was that a visit to the exhibition would be educational, the family visits are examined for instances of learning and analyzed to determine the factors that influenced the learning. Constructivism forms the basis for understanding the process of learning during family visits. The analysis is supported by reference to research from the fields of museum studies, education, and environmental design. The analysis of the educational significance and potential of family visits to an early childhood exhibition leads to the conclusion that specific features may facilitate learning in such an environment. Those features are represented in a set of guidelines for the development and evaluation of early childhood exhibitions. The guidelines suggest attention must be given to the ambience of the space, the general layout of the space, the exhibits, the copy and graphics, additional programs and information, the subtle influences of the building and the staff, and the learning processes of young children, adults, and intergenerational groups. The guidelines suggest specific issues to consider to develop a space that is stimulating and memorable, responsive to the needs of the two distinct visitor groups (young children and adults), and conducive to learning.
Munroe, Elizabeth Ann
Exercise Hemodynamics Enhance Diagnosis of Early Heart Failure with Preserved Ejection Fraction
Background When advanced, heart failure (HF) with preserved ejection fraction (HFpEF) is readily apparent. However, diagnosis of earlier disease may be challenging, as exertional dyspnea is not specific for HF, and biomarkers and hemodynamic indicators of volume overload may be absent at rest. Methods and Results Patients with exertional dyspnea and EF>50% were referred for hemodynamic catheterization. Those with no significant coronary disease, normal BNP, and normal resting hemodynamics (mean pulmonary artery (PA) pressure<25 mmHg & PA wedge (PCWP) pressure <15 mmHg; n=55) underwent exercise study. The exercise PCWP was used to classify patients as having HFpEF (PCWP?25 mmHg; n=32) or non-cardiac dyspnea (NCD, PCWP<25 mmHg; n=23). At rest, HFpEF patients displayed higher resting PA pressures and PCWP, though all values fell within normal limits. Exercise-induced elevation in PCWP in HFpEF was confirmed by greater increases in left ventricular end-diastolic pressure, and was associated with blunted increases in heart rate, systemic vasodilation and cardiac output. Exercise-induced pulmonary hypertension was present in 88% of HFpEF patients and was related principally to elevated PCWP, as pulmonary vascular resistances dropped similarly in both groups. Exercise PCWP and PASP were highly correlated. An exercise PASP?45mmHg identified HFpEF with 96% sensitivity and 95% specificity. Conclusions Euvolemic patients with exertional dyspnea, normal BNP and normal cardiac filling pressures at rest may have markedly abnormal hemodynamic responses during exercise, suggesting that chronic symptoms are related to heart failure. Earlier and more accurate diagnosis using exercise hemodynamics may allow better targeting of interventions to treat and prevent HFpEF progression.
Borlaug, Barry A.; Nishimura, Rick A.; Sorajja, Paul; Lam, Carolyn S.P.; Redfield, Margaret M.
Peripheral arterial disease (PAD) is an atherosclerotic-driven condition that remains underdiagnosed and undertreated. In diabetic patients, PAD begins early, progresses rapidly, and is frequently asymptomatic, making it difficult to diagnose. Strict management of the metabolic instigators and use of screening techniques for PAD in diabetes can facilitate early diagnosis and reduce progression. Exercise is an equally effective treatment option in improving walking distance. Early revascularization must be offered early in suitable patients. Surgical bypass and endovascular revascularization are complementary and the choice of intervention should be applied appropriately by a multidisciplinary vascular team on a selective, patient-specific basis. PMID:24582096
Mascarenhas, Janice V; Albayati, Mostafa A; Shearman, Clifford P; Jude, Edward B
Surface enhanced Raman spectroscopic (SERS) study of saliva in the early detection of oral cancer
NASA Astrophysics Data System (ADS)
Worldwide, oral cancer is the sixth most common cancer for both sexes. In Singapore, the 5-year survival rate of oral cancer is about 50%. The high mortality rate has been attributed to the difficulties in detecting the disease in an early treatable stage. Currently, the standard screening procedures for oral cancer are histopathology examination of biopsied tissues and exfoliative cytological assessment. These techniques, unfortunately, are low in sensitivity. In this study, we exploit the high amplification factor of SERS to investigate on the possibility of utilising molecular vibrational information from saliva samples to detect oral cancer early. All raw saliva samples were centrifuged at 13,000 krpm for 5 minutes to remove unwanted particles prior to SERS measurements. The purified saliva samples were then applied directly on gold particle films, followed by excitation with a 633 nm HeNe laser. SERS spectrum can be obtained in less than 2 minutes for each sample. We have studied the saliva spectra acquired from 5 normal individuals and 5 patients with oral cancer. In addition, we also observe new peaks at 1097 cm-1 and 1627 cm-1 in some of the abnormal samples. These peaks are not present in the spectra acquired from the normal samples. Preliminary measurements will be presented. This study may lead to the development of a sensitive and portable diagnostics system for oral cancer.
Kho, Kiang W.; Malini, Olivo; Shen, Ze Xiang; Soo, Khee Chee
Clinical characteristics and role of early cardiac magnetic resonance imaging in patients with suspected ST-elevation myocardial infarction and normal coronary arteries
A variety of conditions other than acute myocardial infarction may cause ST-elevation. Our objective was to evaluate the impact\\u000a of cardiac magnetic resonance (CMR) on differential diagnosis from a prospective series of patients with suspected ST-elevation\\u000a myocardial infarction (STEMI) and completely normal coronary arteries. Among 1,145 patients with suspected STEMI, 49 patients\\u000a had completely normal coronary arteries and entered a
K. H. StensaethE; E. Fossum; P. Hoffmann; A. Mangschau; N. E. Klow
Excess Optical Enhancement Observed with ARCONS for Early Crab Giant Pulses
NASA Astrophysics Data System (ADS)
We observe an extraordinary link in the Crab pulsar between the enhancement of an optical pulse and the timing of the corresponding giant radio pulse. At optical through infrared wavelengths, our observations use the high time resolution of ARray Camera for Optical to Near-IR Spectrophotometry, a unique superconducting energy-resolving photon-counting array at the Palomar 200 inch telescope. At radio wavelengths, we observe with the Robert C. Byrd Green Bank Telescope and the Green Bank Ultimate Pulsar Processing Instrument backend. We see an 11.3% ± 2.5% increase in peak optical flux for pulses that have an accompanying giant radio pulse arriving near the peak of the optical main pulse, in contrast to a 3.2% ± 0.5% increase when an accompanying giant radio pulse arrives soon after the optical peak. We also observe that the peak of the optical main pulse is 2.8% ± 0.8% enhanced when there is a giant radio pulse accompanying the optical interpulse. We observe no statistically significant spectral differences between optical pulses accompanied by and not accompanied by giant radio pulses. Our results extend previous observations of optical-radio correlation to the time and spectral domains. Our refined temporal correlation suggests that optical and radio emission are indeed causally linked, and the lack of spectral differences suggests that the same mechanism is responsible for all optical emission.
Strader, M. J.; Johnson, M. D.; Mazin, B. A.; Spiro Jaeger, G. V.; Gwinn, C. R.; Meeker, S. R.; Szypryt, P.; van Eyken, J. C.; Marsden, D.; O'Brien, K.; Walter, A. B.; Ulbricht, G.; Stoughton, C.; Bumble, B.
Novel Polypyrrole-Coated Polylactide Scaffolds Enhance Adipose Stem Cell Proliferation and Early Osteogenic Differentiation
An electrically conductive polypyrrole (PPy) doped with a bioactive agent is an emerging functional biomaterial for tissue engineering. We therefore used chondroitin sulfate (CS)-doped PPy coating to modify initially electrically insulating polylactide resulting in novel osteogenic scaffolds. In situ chemical oxidative polymerization was used to obtain electrically conductive PPy coating on poly-96L/4D-lactide (PLA) nonwoven scaffolds. The coated scaffolds were characterized and their electrical conductivity was evaluated in hydrolysis. The ability of the coated and conductive scaffolds to enhance proliferation and osteogenic differentiation of human adipose stem cells (hASCs) under electrical stimulation (ES) in three-dimensional (3D) geometry was compared to the noncoated PLA scaffolds. Electrical conductivity of PPy-coated PLA scaffolds (PLA-PPy) was evident at the beginning of hydrolysis, but decreased during the first week of incubation due to de-doping. PLA-PPy scaffolds enhanced hASC proliferation significantly compared to the plain PLA scaffolds at 7 and 14 days. Furthermore, the alkaline phosphatase (ALP) activity of the hASCs was generally higher in PLA-PPy seeded scaffolds, but due to patient variation, no statistical significance could be determined. ES did not have a significant effect on hASCs. This study highlights the potential of novel PPy-coated PLA scaffolds in bone tissue engineering.
Pelto, Jani; Bjorninen, Miina; Palli, Aliisa; Talvitie, Elina; Hyttinen, Jari; Mannerstrom, Bettina; Suuronen Seppanen, Riitta; Kellomaki, Minna; Miettinen, Susanna; Haimi, Suvi
Novel polypyrrole-coated polylactide scaffolds enhance adipose stem cell proliferation and early osteogenic differentiation.
An electrically conductive polypyrrole (PPy) doped with a bioactive agent is an emerging functional biomaterial for tissue engineering. We therefore used chondroitin sulfate (CS)-doped PPy coating to modify initially electrically insulating polylactide resulting in novel osteogenic scaffolds. In situ chemical oxidative polymerization was used to obtain electrically conductive PPy coating on poly-96L/4D-lactide (PLA) nonwoven scaffolds. The coated scaffolds were characterized and their electrical conductivity was evaluated in hydrolysis. The ability of the coated and conductive scaffolds to enhance proliferation and osteogenic differentiation of human adipose stem cells (hASCs) under electrical stimulation (ES) in three-dimensional (3D) geometry was compared to the noncoated PLA scaffolds. Electrical conductivity of PPy-coated PLA scaffolds (PLA-PPy) was evident at the beginning of hydrolysis, but decreased during the first week of incubation due to de-doping. PLA-PPy scaffolds enhanced hASC proliferation significantly compared to the plain PLA scaffolds at 7 and 14 days. Furthermore, the alkaline phosphatase (ALP) activity of the hASCs was generally higher in PLA-PPy seeded scaffolds, but due to patient variation, no statistical significance could be determined. ES did not have a significant effect on hASCs. This study highlights the potential of novel PPy-coated PLA scaffolds in bone tissue engineering. PMID:23126228
Pelto, Jani; Björninen, Miina; Pälli, Aliisa; Talvitie, Elina; Hyttinen, Jari; Mannerström, Bettina; Suuronen Seppanen, Riitta; Kellomäki, Minna; Miettinen, Susanna; Haimi, Suvi
Epidermal growth factor-expressing Lactococcus lactis enhances intestinal development of early-weaned pigs.
Stress and incomplete gastrointestinal development in early-weaned piglets represent significant challenges in commercial swine farming. Orally ingested recombinant epidermal growth factor (EGF) has been shown to remain biologically active in the gastrointestinal tract as well as stimulate intestinal development, reducing the incidence of pathogen infection and diarrhea. We have previously shown that the food-grade bacterium Lactococcus lactis can be genetically altered to express biologically active EGF when fed to early-weaned mice. In this study, we assigned 8 pigs to each of 4 groups that were given EGF-expressing L. lactis (EGF-LL), empty vector-expressing L. lactis (EV-LL), recombinant human EGF, or unsupplemented bacterial media, all of which were delivered as 50-mL i.g. doses twice per day. All pigs were killed after 14 d to examine intestinal morphology. Pigs in the EGF-LL group had greater jejunal and duodenal villus heights (P < 0.0001) and intestinal length (P = 0.049) than pigs in the control group. Immunohistochemistry with antibodies against proliferating cell nuclear antigen (PCNA) revealed that the proliferation of intestinal cells was significantly greater in the EGF-LL group than in the control group. PCNA expression and intestinal length also were greater in the EV-LL group, which received L. lactis that did not express EGF, than in the control group (P = 0.049), further supporting the use of naturally occurring intestinal microbes as desirable vectors for recombinant protein delivery. Our data demonstrates the feasibility of delivering a growth factor using common probiotic bacteria to farm animals for commercial practice. PMID:20147464
Kang, Ping; Toms, Derek; Yin, Yulong; Cheung, Queenie; Gong, Joshhua; De Lange, Kees; Li, Julang
Ultrasonographic imaging of the carotid arteries allows assessment of both early and advanced atherosclerotic disease. This noninvasive technique has played a central role in many recent epidemiological studies and is being used increasingly for evaluating the efficacy of atherosclerosis prevention trials. New developments in ultrasound equipment, the use of echocontrast agents, novel applications of three- and four-dimensional sonography and in
Michael Hennerici; Stephen Meairs
Early and mid term mortality after coronary artery bypass grafting in women depends on the surgical protocol: retrospective analysis of 3441 on- and off-pump coronary artery bypass grafting procedures
BACKGROUND: Since 2002 MI and stroke, not cancer, are leading causes of death in women. We studied 30-days and 1 year mortality of 3441 patients undergoing coronary artery bypass grafting (CABG) operations in our institution performed either conventionally or off pump (OPCAB). Our objective was to investigate the gender-related mortality in both groups. PATIENTS AND METHODS: Between 2004 and 2008,
Sandra Eifert; Eckehard Kilian; Andres Beiras-Fernandez; Gerd Juchem; Bruno Reichart; Peter Lamm
Enhanced handling and positioning in early infancy advances development throughout the first year.
Behaviors emerge, in part, from the interplay of infant abilities and caregiver-infant interactions. Cross-cultural and developmental studies suggest caregiver handling and positioning influence infant development. In this prospective, longitudinal study, the effects of 3?weeks of enhanced handling and positioning experiences provided to 14 infants versus control experiences provided to 14 infants at 2?months of age were assessed with follow-up through 15?months of age. Behaviors in prone were immediately advanced. Short-term advancements occurred in multiple behaviors, including prone, head control, reaching, and sitting behaviors. Longer term advancements, up to 12?months after the experience period, occurred in object transfer, crawling and walking behaviors. This suggests broad and long-lasting changes can arise via brief periods of change in caregiver-infant interactions. PMID:22540738
Lobo, Michele A; Galloway, James C
Attentional enhancement via selection and pooling of early sensory responses in human visual cortex
Summary To characterize the computational processes by which attention improves behavioral performance, we measured activity in visual cortex with functional magnetic resonance imaging as humans performed a contrast-discrimination task with focal and distributed attention. Focal attention yielded robust improvements in behavioral performance that were accompanied by increases in cortical responses. Using a quantitative analysis, we determined that if performance were limited only by the sensitivity of the measured sensory signals, the improvements in behavioral performance would have corresponded to an unrealistically large (approximately 400%) reduction in response variability. Instead, behavioral performance was well characterized by a pooling and selection process for which the largest sensory responses, those most strongly modulated by attention, dominated the perceptual decision. This characterization predicts that high contrast distracters that evoke large sensory responses should have a negative impact on behavioral performance. We tested and confirmed this prediction. We conclude that attention enhanced behavioral performance predominantly by enabling efficient selection of the behaviorally relevant sensory signals.
Pestilli, Franco; Carrasco, Marisa; Heeger, David J.; Gardner, Justin L.
An early rehabilitation intervention to enhance recovery during hospital admission for an exacerbation of chronic respiratory disease: randomised controlled trial
Objective To investigate whether an early rehabilitation intervention initiated during acute admission for exacerbations of chronic respiratory disease reduces the risk of readmission over 12 months and ameliorates the negative effects of the episode on physical performance and health status. Design Prospective, randomised controlled trial. Setting An acute cardiorespiratory unit in a teaching hospital and an acute medical unit in an affiliated teaching district general hospital, United Kingdom. Participants 389 patients aged between 45 and 93 who within 48 hours of admission to hospital with an exacerbation of chronic respiratory disease were randomised to an early rehabilitation intervention (n=196) or to usual care (n=193). Main outcome measures The primary outcome was readmission rate at 12 months. Secondary outcomes included number of hospital days, mortality, physical performance, and health status. The primary analysis was by intention to treat, with prespecified per protocol analysis as a secondary outcome. Interventions Participants in the early rehabilitation group received a six week intervention, started within 48 hours of admission. The intervention comprised prescribed, progressive aerobic, resistance, and neuromuscular electrical stimulation training. Patients also received a self management and education package. Results Of the 389 participants, 320 (82%) had a primary diagnosis of chronic obstructive pulmonary disease. 233 (60%) were readmitted at least once in the following year (62% in the intervention group and 58% in the control group). No significant difference between groups was found (hazard ratio 1.1, 95% confidence interval 0.86 to 1.43, P=0.4). An increase in mortality was seen in the intervention group at one year (odds ratio 1.74, 95% confidence interval 1.05 to 2.88, P=0.03). Significant recovery in physical performance and health status was seen after discharge in both groups, with no significant difference between groups at one year. Conclusion Early rehabilitation during hospital admission for chronic respiratory disease did not reduce the risk of subsequent readmission or enhance recovery of physical function following the event over 12 months. Mortality at 12 months was higher in the intervention group. The results suggest that beyond current standard physiotherapy practice, progressive exercise rehabilitation should not be started during the early stages of the acute illness. Trial registration Current Controlled Trials ISRCTN05557928.
Williams, Johanna E A; Hussain, Syed F; Harvey-Dunstan, Theresa C; Bankart, M John; Chaplin, Emma J; Vincent, Emma E; Chimera, Rudo; Morgan, Mike D; Singh, Sally J; Steiner, Michael C
Enhanced evolution by stochastically variable modification of epigenetic marks in the early embryo.
Evolution by gene duplication is generally accepted as one of the crucial driving forces for the gain of new complexity and functions, but the formation of pseudogenes remains a problem for this mechanism. Here we expand on earlier ideas that epigenetic modifications can drive neo- and subfunctionalization in evolution by gene duplication. We explore the effects of stochastic epigenetic modifications on the evolution (and thus development) of complex organisms in a constant environment. Modeling is done both using a modified genetic drift analytical treatment and computer simulations, which were found to agree. A transposon silencing model is also explored. Some key assumptions made include (i) stochastic, incomplete removal (or addition) of repressive epigenetic marks takes place during a window(s) of opportunity in the zygote and early embryo; (ii) there is no statistical variation of the marks after the window closes; and (iii) the genes affected are sensitive to dosage. Our genetic drift treatment takes into account that after gene duplication the prevailing case upon which selection operates is a duplicate/singlet heterozygote; to the best of our knowledge, this has not been considered in previous treatments. We conclude from our modeling that stochastic epigenetic modifications, with rates consistent with experimental observation, can both increase the rate of gene fixation and decrease pseudogenization, thus dramatically improving the efficacy of evolution by gene duplication. We also find that a transposon silencing model is advantageous for fixation of recessive genes in diploid organisms, especially with large effective population sizes. PMID:24733912
Branciamore, Sergio; Rodin, Andrei S; Riggs, Arthur D; Rodin, Sergei N
Loschmidt echo with a nonequilibrium initial state: Early-time scaling and enhanced decoherence
NASA Astrophysics Data System (ADS)
We study the Loschmidt echo (LE) in a central spin model in which a central spin is globally coupled to an environment (E) which is subjected to a small and sudden quench at t=0, so that its state at t=0+ remains the same as the ground state of the initial environmental Hamiltonian before the quench; this leads to a nonequilibrium situation. This state now evolves with two Hamiltonians, the final Hamiltonian following the quench and its modified version which incorporates an additional term arising due to the coupling of the central spin to the environment. Using a generic short-time scaling of the decay rate, we establish that in the early-time limit, the rate of decay of the LE close to the quantum critical point (QCP) of E is independent of the quenching. We also study the temporal evolution of the LE and establish the presence of a crossover to a situation where the quenching becomes irrelevant. In the limit of large quench amplitude the nonequilibrium initial condition is found to result in a drastic increase in decoherence at large times, even far away from a QCP. These generic results are verified analytically as well as numerically, choosing E to be a transverse Ising chain where the transverse field is suddenly quenched.
Mukherjee, Victor; Sharma, Shraddha; Dutta, Amit
Enhanced evolution by stochastically variable modification of epigenetic marks in the early embryo
Evolution by gene duplication is generally accepted as one of the crucial driving forces for the gain of new complexity and functions, but the formation of pseudogenes remains a problem for this mechanism. Here we expand on earlier ideas that epigenetic modifications can drive neo- and subfunctionalization in evolution by gene duplication. We explore the effects of stochastic epigenetic modifications on the evolution (and thus development) of complex organisms in a constant environment. Modeling is done both using a modified genetic drift analytical treatment and computer simulations, which were found to agree. A transposon silencing model is also explored. Some key assumptions made include (i) stochastic, incomplete removal (or addition) of repressive epigenetic marks takes place during a window(s) of opportunity in the zygote and early embryo; (ii) there is no statistical variation of the marks after the window closes; and (iii) the genes affected are sensitive to dosage. Our genetic drift treatment takes into account that after gene duplication the prevailing case upon which selection operates is a duplicate/singlet heterozygote; to the best of our knowledge, this has not been considered in previous treatments. We conclude from our modeling that stochastic epigenetic modifications, with rates consistent with experimental observation, can both increase the rate of gene fixation and decrease pseudogenization, thus dramatically improving the efficacy of evolution by gene duplication. We also find that a transposon silencing model is advantageous for fixation of recessive genes in diploid organisms, especially with large effective population sizes.
Branciamore, Sergio; Rodin, Andrei S.; Riggs, Arthur D.; Rodin, Sergei N.
Background Several in vivo and in vitro studies have shown that metal-rich particles may enhance allergic responses to house dust mites and induce an increased release of allergy-related cytokines. Objectives The main goal of this analysis is to define the possible association of intrauterine exposure to lead and mercury with the occurrence of skin sensitization to common aeroallergens in early childhood. Material and Methods The present study refers to a sample of 224 women in the second trimester of pregnancy recruited from Krakow inner city area who had full term pregnancies and whose children underwent skin prick testing (SPT) at the age of 5. Lead and mercury levels were assessed in cord blood and retested in children at age of 5 years. Aeroallergen concentrations in house dust were measured at the age of 3 years. The main health outcome (atopic status) was defined as the positive SPT to at least one common aeroallergen (Der f1, Der p1, Can f1 and Fel d1) at the age of 5 years. In the statistical analysis of the association between atopic status of children and exposure to metals, the study considered a set of covariates such as maternal characteristics (age, education, atopy), child's gender, number of older siblings, prenatal (measured via cord blood cotinine) and postnatal environmental tobacco smoke together with exposure to polycyclic aromatic hydrocarbons (PAH) as measured by PAH-DNA adducts. Results and conclusion In the binary regression analysis, which controlled for the confounders, the risk ratio (RR) estimate for atopic sensitization was significantly associated with the lead exposure (RR =2.25, 95%CI: 1.21–4.19). In conclusion, the data suggest that even very low-level of prenatal lead exposure may be implicated in enhancing sensitization to common aeroallergens in early childhood.
Jedrychowski, Wieslaw; Perera, Frederica; Maugeri, Umberto; Miller, Rachel L.; Rembiasz, Maria; Flak, Elzbieta; Mroz, Elzbieta; Majewska, Renata; Zembala, Marek
Early ischemia enhances action potential-dependent, spontaneous glutamatergic responses in CA1 neurons
Two types of quantal spontaneous neurotransmitter release are present in the nervous system, namely action potential (AP)-dependent release and AP-independent release. Previous studies have identified and characterized AP-independent release during hypoxia and ischemia. However, the relative contribution of AP-dependent spontaneous release to the overall glutamate released during transient ischemia has not been quantified. Furthermore, the neuronal activity that mediates such release has not been identified. Using acute brain slices, we show that AP-dependent release constitutes approximately one-third of the overall glutamate-mediated excitatory postsynaptic potentials/currents (EPSPs/EPSCs) measured onto hippocampal CA1 pyramidal neurons. However, during transient (2?mins) in vitro hypoxia–hypoglycemia, large-amplitude, AP-dependent spontaneous release is significantly enhanced and contributes to 74% of the overall glutamatergic responses. This increased AP-dependent release is due to hyper-excitability in the presynaptic CA3 neurons, which is mediated by the activity of NMDA receptors. Spontaneous glutamate release during ischemia can lead to excitotoxicity and perturbation of neural network functions.
Ye, Hui; Jalini, Shirin; Zhang, Liang; Charlton, Milton; Carlen, Peter L
Fluorescence-enhanced optical spectroscopy using early arriving photons in transmission mode: a finite element approach
NASA Astrophysics Data System (ADS)
Optical imaging of turbid media is a challenging problem mainly due to the scattering process that reduces image contrast and degrades spatial resolution. The development of fluorescent probes has recently improved the noninvasive optical technique. In this paper, we are interested in the time gating fluorescence signals. The diffusion approximation is used in order to describe the light propagation of a laser pulse in a turbid media that mimics breast like biological tissue. A numerical model based on a finite element method is proposed. Fluorescence time dependent numerical simulations are performed in order to compute time-gated intensities resulting from line scans across partially absorbing and scattering slab configurations. Optical properties of embedded objects are chosen to be the same as optical properties of breast tumor. Tacking into account two hidden objects, we investigate the lateral resolution aimed by fluorescence modality, and we also compared the results to thus obtained by photon propagation. Different widths of the time gate are computed and it is demonstrated that both lateral localization of one inclusion, and resolution of two inclusions, are enhanced when the time-gate width (?t) is decreased. The overall computations confirm that fluorescent time-gating technique is very sensitive to local variations in optical properties that are due to breast-like tumors in turbid media.
Piron, Vianney; L'Huillier, Jean-Pierre
Bone structure and strength are enhanced in rats programmed by early overfeeding.
Childhood obesity is growing in prevalence. Obesity and bone dysfunctions may be related disorders, and therefore our aim was to study the impact of the early overfeeding (EO) in offspring bone health since weaning up to adulthood. To induce EO during lactation, litter size was adjusted to 3 male rats per litter (SL). Litter containing 10 pups per mother was the control (NL). Bone tissue was evaluated by dual-energy X-ray absorptiometry, computed tomography, microcomputed tomography, biomechanical tests, and serum analyses. SL offspring presented higher body weight, fat mass, lean mass from 21 up to 180 days, hyperphagia, and higher visceral fat mass. Bone analysis showed that SL offspring presented higher total bone mineral density (BMD) only at 180 days, and higher total bone mineral content and higher bone area from 21 until 180 days. At 180 days, SL offspring presented higher femur BMD and fourth lumbar vertebra (LV4) BMD, higher femoral head radiodensity and LV4 vertebral body radiodensity, lower trabecular pattern factor and trabecular separation, however with higher trabecular number, higher maximal load, resilience, stiffness and break load, and lower break deformation. SL group had, at 180 days, higher osteocalcin and lower C-terminal cross-linked telopeptide of type I collagen (CTX I). We have shown that the excess of fat mass contributed to an increased bone mass, and hypothesized that this increase could be mediated by the hypothyroidism and previous higher thyroid hormone action and hyperleptinemia at weaning. Furthermore, the increased biomechanical loading due to increased body weight probably help us to understand the protective effects obesity exerts upon bone health. PMID:24627101
de Albuquerque Maia, L; Lisboa, P C; de Oliveira, E; da Conceiçăo, E P S; Lima, I C B; Lopes, R T; Ruffoni, L D G; Nonaka, K O; de Moura, E G
Popliteal artery war injuries.
The early postoperative results of 44 surgically treated popliteal arterial injuries from the Yugoslav civil war are reported. Of these patients, 41 (93%) were males and three (7%) were females, average age was 28 (range 6-45) years. Twenty patients (45%) had gunshot wounds and 24 (55%) explosive wounds. Twelve (28%) suffered isolated vascular damage, while 32 (72%) suffered concomitant bone fractures. Isolated arterial lesions were found in 24 (55%) cases, and concomitant arterial and venous lesions in 20 (45%). Twenty-four (55%) had primary reconstructions after haemostasis in the initial war hospital, and 20 (45%) secondary reconstructions after inadequate primary reconstruction in a regional war hospital. Artery procedures included 19 reverse saphenous vein graft interpositions, 10 reverse saphenous vein bypasses, 12 'in situ' saphenous vein bypasses and five lateral subcutaneous saphenous vein bypasses. The early graft patency rate was 100%, and limb salvage 72%. Major amputation was performed in 28%. Concomitant bone fractures, secondary reconstructions, secondary haemorrhage from an infected graft, and explosion wounds significantly increased the amputation rate (P < 0.01). Eleven amputations were performed after an anatomic, and only one after an extra-anatomic reconstruction (P < 0.01). The authors recommend an in situ or lateral subcutaneous reconstruction in cases of complicated popliteal artery injuries, such as concomitant bone fractures accompanied by massive soft tissue damage, and this type of reconstruction should also be used if infection is present or the procedure is delayed. PMID:9158121
Davidovi?, L; Lotina, S; Kosti?, D; Velimirovi?, D; Duki?, P; Cinara, I; Vranes, M; Markovi?, M
A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: I. Simulations
NASA Astrophysics Data System (ADS)
Widespread adoption of quantitative pharmacokinetic modeling methods in conjunction with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has led to increased recognition of the importance of obtaining accurate patient-specific arterial input function (AIF) measurements. Ideally, DCE-MRI studies use an AIF directly measured in an artery local to the tissue of interest, along with measured tissue concentration curves, to quantitatively determine pharmacokinetic parameters. However, the numerous technical and practical difficulties associated with AIF measurement have made the use of population-averaged AIF data a popular, if sub-optimal, alternative to AIF measurement. In this work, we present and characterize a new algorithm for determining the AIF solely from the measured tissue concentration curves. This Monte Carlo blind estimation (MCBE) algorithm estimates the AIF from the subsets of D concentration-time curves drawn from a larger pool of M candidate curves via nonlinear optimization, doing so for multiple (Q) subsets and statistically averaging these repeated estimates. The MCBE algorithm can be viewed as a generalization of previously published methods that employ clustering of concentration-time curves and only estimate the AIF once. Extensive computer simulations were performed over physiologically and experimentally realistic ranges of imaging and tissue parameters, and the impact of choosing different values of D and Q was investigated. We found the algorithm to be robust, computationally efficient and capable of accurately estimating the AIF even for relatively high noise levels, long sampling intervals and low diversity of tissue curves. With the incorporation of bootstrapping initialization, we further demonstrated the ability to blindly estimate AIFs that deviate substantially in shape from the population-averaged initial guess. Pharmacokinetic parameter estimates for Ktrans, kep, vp and ve all showed relative biases and uncertainties of less than 10% for measurements having a temporal sampling rate of 4 s and a concentration measurement noise level of ? = 0.04 mM. A companion paper discusses the application of the MCBE algorithm to DCE-MRI data acquired in eight patients with malignant brain tumors.
Schabel, Matthias C.; Fluckiger, Jacob U.; DiBella, Edward V. R.
A Model-Constrained Monte Carlo Method for Blind Arterial Input Function Estimation in Dynamic Contrast-Enhanced MRI: I) Simulations
Widespread adoption of quantitative pharmacokinetic modeling methods in conjunction with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has led to increased recognition of the importance of obtaining accurate patient-specific arterial input function (AIF) measurements. Ideally, DCE-MRI studies use an AIF directly measured in an artery local to the tissue of interest, along with measured tissue concentration curves, to quantitatively determine pharmacokinetic parameters. However, the numerous technical and practical difficulties associated with AIF measurement have made the use of population-averaged AIF data a popular, if suboptimal, alternative to AIF measurement. In this work, we present and characterize a new algorithm for determining the AIF solely from the measured tissue concentration curves. This Monte Carlo Blind Estimation (MCBE) algorithm estimates the AIF from subsets of D concentration-time curves drawn from a larger pool of M candidate curves via nonlinear optimization, doing so for multiple (Q) subsets and statistically averaging these repeated estimates. The MCBE algorithm can be viewed as a generalization of previously published methods that employ clustering of concentration-time curves and only estimate the AIF once. Extensive computer simulations were performed over physiologically- and experimentally-realistic ranges of imaging and tissue parameters, and the impact of choosing different values of D and Q was investigated. We found the algorithm to be robust, computationally-efficient, and capable of accurately estimating the AIF even for relatively high noise levels, long sampling intervals, and low diversity of tissue curves. With the incorporation of boostrapping initialization, we further demonstrated the ability to blindly estimate AIFs that deviate substantially in shape from the population-averaged initial guess. Pharmacokinetic parameter estimates for Ktrans, kep, vp, and ve all showed relative biases and uncertainties of less than 10% for measurements having a temporal sampling rate of 4 seconds and a concentration measurement noise level of ? = 0.04 mM. A companion paper discusses the application of the MCBE algorithm to DCE-MRI data acquired in eight patients with malignant brain tumors.
Schabel, Matthias C.; Fluckiger, Jacob U.; DiBella, Edward V. R.
Evaluation of meglumine gadoterate-enhanced MR angiography (MRA) compared with time-of-flight MRA in the diagnosis of clinically significant non-coronary arterial disease: a pooled analysis of data from two clinical trials
Objectives We analysed pooled data from two clinical trials to assess the diagnostic accuracy and safety of meglumine gadoterate (Gd-DOTA)-enhanced MR angiography (MRA) relative to those of non-enhanced time-of-flight (TOF) MRA for non-coronary arterial disease. Both techniques were compared with X-ray angiography as the gold standard. Methods Patients were of both sexes, were aged at least 18 years and had suspected non-coronary arterial disease. Each patient was his/her own control and underwent TOF MRA followed by Gd-DOTA-enhanced MRA, and then X-ray angiography. MRA was performed at 1.5 T (USA study) or 3 T (Republic of Korea study). The primary criterion used to evaluate efficacy was the degree to which the MRA examination agreed with X-ray angiography in assessing non-coronary arterial lesions. The performance of Gd-DOTA over TOF was assessed using a one-sided paired t-test. We also evaluated the specificity, sensitivity, image quality, examination duration and clinical safety of both MRA procedures. Results In total, 192 patients were enrolled and received Gd-DOTA. In the intent-to-treat population (n=162), within-patient accuracy was significantly greater for Gd-DOTA than for TOF (85.8±19.8% agreement between Gd-DOTA and X-ray angiography compared with 78.3±24.9% agreement between TOF and X-ray angiography; p=0.0001). The sensitivity, specificity, image quality and examination duration were also better for Gd-DOTA than for TOF. There were no serious drug-related adverse events. Conclusion We conclude that Gd-DOTA-enhanced MRA is a safe and accurate procedure for detecting arterial stenosis at both 1.5 T and 3 T.
Shah, D J; Lim, T-H
Detecting Hepatocellular Carcinoma: Value of Unenhanced or Arterial Phase CT Imaging or Both Used in Conjunction with Conventional Portal Venous Phase Contrast Enhanced CT Imaging
OBJECTIVE. Because rates of detection of hypervascular neoplasms by conventional dynamic incremental-bolus CT are lower than rates of detection of hypovascular tumors by ?::?and because both unenhanced CT imaging and arterial phase helical CT imaging may increase the detection of hypervascular tumors, such as hepatocellular carcinoma, we eval- uated the value of unenhanced and arterial phase CT imaging used in
James H. Oliver; Richard L Baron; Michael P. Federle; Howard E. Rockette
Enhanced detection of proximal right coronary artery stenosis with the additional analysis of right ventricular thallium-201 uptake in stress scintigrams
The value of right ventricular thallium-201 analysis in detecting proximal right coronary artery stenosis in exercise myocardial scintigraphy was analyzed in 52 patients, 27 with and 25 without proximal right coronary artery stenosis. For the detection of proximal right coronary artery stenosis, the sensitivity and specificity of thallium scintigraphic analysis were 59 and 88% for a right ventricular abnormality, 67 and 68% for a left ventricular inferior wall abnormality, and 93 and 56% for an abnormality of either. When both right and left ventricular thallium images were abnormal, all 9 patients had proximal right coronary artery stenoses, and when both were normal, 26 of 28 patients had a normal proximal right coronary artery. The sensitivity and specificity of blood pool scintigraphic variables during exercise (right ventricular ejection fraction and left ventricular inferior wall motion) were not significantly different for detection of proximal right coronary artery stenosis. Thus, the additional analysis of the right ventricle on thallium-201 stress scintigrams can improve the detection of proximal right coronary artery stenosis. When both right ventricular and left ventricular thallium scintigrams are abnormal (or normal), the ability to predict the presence (or absence) of proximal right coronary artery stenosis is very high.
Gutman, J.; Brachman, M.; Rozanski, A.; Maddahi, J.; Waxman, A.; Berman, D.S.
Surgical and intensive care patients are at a heightened risk for arterial embolization due to pre-existing conditions such as age, hypercoagulability, cardiac abnormalities and atherosclerotic disease. Most arterial emboli are clots that originate in the heart and travel to distant vascular beds where they cause arterial occlusion, ischemia, and potentially infarction. Other emboli form on the surface of eroded arterial plaque or within its lipid core. Thromboemboli are large clots that dislodge from the surface of athesclerotic lesions and occlude distal arteries causing immediate ischemia. Atheroemboli, which originate from fracturing the lipid core tend to cause a process of organ dysfunction and systemic inflammation, termed cholesterol embolization syndrome. The presentation of arterial emboli depends on the arterial bed that is affected. The most common manifestations are strokes and acute lower limb ischemia. Less frequently, emboli target the upper extremities, mesenteric or renal arteries. Treatment involves rapid diagnosis, which may be aided by precise imaging studies and restoration of blood flow. The type of emboli, duration of presentation, and organ system affected determines the treatment course. Long-term therapy includes supportive medical care, identification of the source of embolism and prevention of additional emboli. Patients who experienced arterial embolism as a result of clots formed in the heart should be anticoagulated. Arterial emboli from atherosclerotic disease of the aorta or other large arteries should prompt treatment to reduce the risk for atherosclerotic progression, such as anti-platelet therapy and the use of statin drugs. The use of anticoagulation and surgical intervention to reduce the risk of arterial embolization from atherosclerotic lesions is still being studied.
Lyaker, Michael R.; Tulman, David B.; Dimitrova, Galina T.; Pin, Richard H.; Papadimos, Thomas J.
Early Detection of Lewis Lung Carcinoma Tumor Control by Irradiation Using Diffusion-Weighted and Dynamic Contrast-Enhanced MRI
Purpose To investigate the correlation between diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) derived parameters and radioresponsiveness of Lewis lung carcinoma (LLC) tumor. Materials and Methods LLC tumor growth in C57BL/6 mouse limb was used for the experiment. The tumors were irradiated with 10 Gy×5, or 30 Gy×2 vs. sham irradiation. Fourteen tumors were subjected to DW-MRI and DCE-MRI pre-radiotherapy and weekly imaging after radiotherapy. The temporal changes in apparent diffusion coefficient (ADC) and DCE-MRI derived parameters (Ktrans, kep, ve, and vp) were correlated with tumor size, and were histologically compared with CD31 staining of resected tumors. Results The 10 Gy×5 dose inhibited tumor growth for a week, while 30 Gy×2 controlled tumor growth for a 3-week observation period. One week after radiotherapy (week 2), irradiated tumors showed significantly higher values of ADC than untreated ones (10 Gy×5, p?=?0.004; 30 Gy×2, p?=?0.01). Significantly higher values of ve were shown earlier by 30 Gy×2 vs. sham (p?=?0.01) and 10 Gy×5 vs. sham irradiation (p?=?0.05). Sustained higher ve from 10 Gy×5 compared to sham irradiated tumors was evident at week 3 (p?=?0.016) and week 4 (p?=?0.046). A 13.8% early increase in ADC for 30 Gy×2 tumor group (p?=?0.002) and a 16.5% increase for 10 Gy×5 group were noted (p?=?0.01) vs. sham irradiation (which showed a 2.2% decrease). No differences were found for Ktrans, kep, or vp. Both radiotherapy groups demonstrated significant reduction in microvessel counts. Conclusion Early increase in ADC and ve correlated with tumor control by irradiation.
Cheng, Jason Chia-Hsien; Yuan, Ang; Chen, Jyh-Horng; Lu, Yi-Chien; Cho, Kuan-Hung; Wu, Jian-Kuen; Wu, Chien-Jang; Chang, Yeun-Chung; Yang, Pan-Chyr
The enhanced value of combining conventional and 'omics' analyses in early assessment of drug-induced hepatobiliary injury
The InnoMed PredTox consortium was formed to evaluate whether conventional preclinical safety assessment can be significantly enhanced by incorporation of molecular profiling ('omics') technologies. In short-term toxicological studies in rats, transcriptomics, proteomics and metabolomics data were collected and analyzed in relation to routine clinical chemistry and histopathology. Four of the sixteen hepato- and/or nephrotoxicants given to rats for 1, 3, or 14 days at two dose levels induced similar histopathological effects. These were characterized by bile duct necrosis and hyperplasia and/or increased bilirubin and cholestasis, in addition to hepatocyte necrosis and regeneration, hepatocyte hypertrophy, and hepatic inflammation. Combined analysis of liver transcriptomics data from these studies revealed common gene expression changes which allowed the development of a potential sequence of events on a mechanistic level in accordance with classical endpoint observations. This included genes implicated in early stress responses, regenerative processes, inflammation with inflammatory cell immigration, fibrotic processes, and cholestasis encompassing deregulation of certain membrane transporters. Furthermore, a preliminary classification analysis using transcriptomics data suggested that prediction of cholestasis may be possible based on gene expression changes seen at earlier time-points. Targeted bile acid analysis, based on LC-MS metabonomics data demonstrating increased levels of conjugated or unconjugated bile acids in response to individual compounds, did not provide earlier detection of toxicity as compared to conventional parameters, but may allow distinction of different types of hepatobiliary toxicity. Overall, liver transcriptomics data delivered mechanistic and molecular details in addition to the classical endpoint observations which were further enhanced by targeted bile acid analysis using LC/MS metabonomics.
Ellinger-Ziegelbauer, Heidrun, E-mail: email@example.com [Bayer Schering Pharma AG, Wuppertal (Germany); Adler, Melanie [University of Wuerzburg, Wuerzburg (Germany); Amberg, Alexander [Sanofi aventis R and D, Disposition, Safety and Animal Research, Frankfurt (Germany); Brandenburg, Arnd [Genedata AG, Basel (Switzerland); Callanan, John J. [UCD School of Biomolecular and Biomedical Science and School of Agriculture, Food Science and Veterinary Medicine, UCD Conway Institute, University College Dublin, Dublin (Ireland); Connor, Susan [MetaPro (United Kingdom); Fountoulakis, Michael [Hoffmann-La Roche AG, Basel (Switzerland); Gmuender, Hans [Genedata AG, Basel (Switzerland); Gruhler, Albrecht [Novo Nordisk A/S, Maaloev (Denmark); Hewitt, Philip [Merck KGaA Darmstadt (Germany); Hodson, Mark [MetaPro (United Kingdom); Matheis, Katja A. [Boehringer Ingelheim Pharma GmbH and Co. KG, Biberach (Germany); McCarthy, Diane [Bio-Rad, Laboratories, Hercules, CA (United States); Raschke, Marian; Riefke, Bjoern [Bayer Schering Pharma AG, Berlin (Germany); Schmitt, Christina S. [Merck KGaA Darmstadt (Germany); Sieber, Max [University of Wuerzburg, Wuerzburg (Germany); Sposny, Alexandra [Merck KGaA Darmstadt (Germany); Suter, Laura [Hoffmann-La Roche AG, Basel (Switzerland); Sweatman, Brian [MetaPro (United Kingdom)
Late gadolinium enhancement by cardiovascular magnetic resonance is complementary to left ventricle ejection fraction in predicting prognosis of patients with stable coronary artery disease
Background Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) predicts adverse prognosis in patients with stable coronary artery disease (CAD). However, the interaction with conventional risk factors remains uncertain. Our aim was to assess whether the extent of LGE is an independent predictor of adverse cardiac outcome beyond conventional risk factors, including left ventricle ejection fraction (LVEF). Methods We enrolled 376 patients (88% males, 64?±?11?years) with stable CAD, who underwent LGE assessment and a detailed conventional evaluation (clinical and pharmacological history, risk factors, ECG, Echocardiography). During a follow-up of 38?±?21?months, 56 events occurred (32 deaths, 24 hospitalizations for heart failure). Results LGE and LVEF showed the strongest univariate associations with end-points (HR: 13.61 [95%C.I.: 7.32-25.31] for LGE???45% of LV mass; and 12.34 [6.80-22.38] for LVEF???30%; p?0.0001). Multivariate analysis identified baseline LVEF, loop diuretic therapy, moderate-severe mitral regurgitation and pulmonary hypertension as significant predictors among conventional risk factors. According to a step-wise approach, LGE showed strong association with prognosis as well (5.25 [2.64-10.43]; p?0.0001). LGE significantly improved the model predictability (chi-square 239 vs 221, F-test p?0.0001) with an additive effect on the prognostic power of LVEF, which however retained its prognostic power (4.89 [2.50-09.56]; p?0.0001). Patients with LGE???45% and/or LVEF???30% had much worse prognosis compared to patients without risk factors (annual event rates of 43% vs 3%; p?0.0001). Interestingly LGE was a significant predictor when all cause mortality was analyzed as the only endpoint. Conclusions This study demonstrates that LGE assessed by CMR is a robust independent non-invasive marker of prognosis in stable CAD patients. LGE can integrate the available metrics to substantially improve risk stratification.
Perfusion imaging of cerebral arteriovenous malformations: a study comparing quantitative continuous arterial spin labeling and dynamic contrast-enhanced magnetic resonance imaging at 3 T.
Assessment of hemodynamics in arteriovenous malformations (AVMs) is important for estimating the risk of bleeding as well as planning and monitoring therapy. In tissues with perfusion values significantly higher than cerebral cortex, continuous arterial spin labeling (CASL) permits both adequate representation and quantification of perfusion. Thirteen patients who had cerebral AVMs were examined with two magnetic resonance imaging (MRI) techniques: perfusion imaging using a CASL technique with two delay times, 800 and 1200 ms, and T(2)-weighted dynamic contrast-enhanced MRI (T(2)-DCE-MRI). The signal-to-noise ratio obtained in our study with the CASL technique at 3 T was sufficient to estimate perfusion in gray matter. Both nidal and venous perfusion turned out larger by factors of 1.71±2.01 and 2.48±1.51 in comparison to T(2)-DCE-MRI when using CASL at delay times of 800 and 1200 ms, respectively. Moreover, the venous and nidal perfusion values of the AVMs measured at T(2)-DCE-MRI did not correlate with those observed at CASL. Evaluation of average perfusion values yielded significantly different results when using a shorter versus a longer delay time. Average gray matter perfusion was 15.8% larger when measured at delay times of w=800 ms versus w=1200 ms, while nidal perfusion was 15.7% larger and venous perfusion was 34.6% larger, respectively. In conclusion, the extremely high perfusion within an AVM could be successfully quantified using CASL. A shorter postlabeling delay time of w=800 ms seems to be more appropriate than a longer time of w=1200 ms because of possible inflow of unlabeled spins at the latter. PMID:21920687
Lüdemann, Lutz; Jedrzejewski, Grzegorz; Heidenreich, Jens; Han, Eric T; Bruhn, Harald
Expression of NADPH oxidases and enhanced H(2)O(2)-generating activity in human coronary artery endothelial cells upon induction with tumor necrosis factor-alpha.
Tumor necrosis factor (TNF)-alpha, which potentiates reactive oxygen species (ROS) generation, is crucial for the development of coronary arteritis and aneurysm in Kawasaki disease. We hypothesized that vascular NADPH oxidase (Nox) enzymes participate in the TNF-alpha-triggered endothelial damage through elevating ROS generation. Thus, we herein examine the expression of Nox enzymes in human coronary artery endothelial cells (HCAEC) and the effects of TNF-alpha on Nox-mediated ROS generation. We show that HCAEC in culture spontaneously generate H(2)O(2) at basal level (0.53 nmol/min/mg protein). In searching for Nox components responsible for the H(2)O(2) generation, two distinct isoforms of Nox4 are found expressed in HCAEC: the prototype Nox4A and the shorter Nox4B, respectively in the postnuclear supernatant and the nuclear fractions. Other expressed Nox family components are: as mRNAs, Nox4C, Nox4D, Nox1, p51(nox), and Racs; as mRNAs and proteins, Nox2, p22(phox), p47(phox), and p67(phox). The H(2)O(2)-generating activity increases up to three-fold upon inclusion of TNF-alpha in culture, concomitantly with augmented expressions of Nox4A, p22(phox), p47(phox) and p67(phox) proteins. Together, these results suggest that Nox2 and Nox4A enzymes are induced by TNF-alpha endowing HCAEC with enhanced ROS-generating activity, which may play a role in the initial endothelial dysfunction through oxidative stress. PMID:18687299
Yoshida, Lucia S; Tsunawaki, Shohko
Scar detection by contrast-enhanced magnetic resonance imaging in chronic coronary artery disease: a comparison with nuclear imaging and echocardiography.
We compared contrast-enhanced MRI (CeMRI) with the most widely used imaging techniques for myocardial infarct (MI) diagnosis, SPECT and Echo, in unselected patients with chronic coronary artery disease (CAD). Two blinded operators assessed scars on MRI, SPECT and Echo images using a 16-segments LV model. We studied 105 consecutive patients: 50 had Q-wave MI (Q-MI), 19 non Q-wave MI or rest angina (nonQ-MI/RA) and 36 effort angina (EA) history. CeMRI was positive, respectively, in 96%, 37%, and 6%, SPECT in 90%, 53%, and 44%, and Echo in 84%, 32%, and 28% of patients (within Q-MI: CeMRI vs. SPECT p < 0.03, vs. Echo p < 0.001; within EA CeMRI vs. SPECT and ECHO p < 0.001; all trends p < 0.001, pseudo r-square: 0.56-0.75 for CeMRI, 0.18-0.28 for SPECT and 0.23-0.37 for Echo). CeMRI and SPECT agreed in 83 patients (79%); negative SPECT with 1 +/- 0 segments subendocardial delayed enhancement (DE) was found in 4 (4%); negative CeMRI with 4 +/- 3 segments perfusion defects in 18 (17%), 16 of whom were obese or showed LBB or sub-occlusion of related coronary. CeMRI and Echo agreed in 78 patients (75%); negative Echo with 2 +/- 1 segments subendocardial DE was found in 13 (12%) and negative CeMRI with 11 +/- 7 segments kinetic abnormalities in 14 (13%), in 10 confirmed by Cine-MRI. In Q-MI, CeMRI detects DE more frequently than perfusion defects and, especially, kinetic abnormalities are found by SPECT and Echo, respectively. CeMRI identifies small areas of DE also in some patients with nonQ-MI or RA but usually not in patients with EA. This biologically plausible decreasing trend is shown by CeMRI more clearly than by SPECT and Echo. Disagreement between CeMRI and SPECT or Echo may be reduced, but perhaps not fully eluded, performing dobutamine Echo and SPECT after maximal epicardial coronary dilatation. PMID:16136853
Catalano, Oronzo; Moro, Guido; Cannizzaro, Giorgio; Mingrone, Renato; Opasich, Cristina; Perotti, Mariarosa; Rognone, Felice; Frascaroli, Mauro; Baldi, Maurizia; Tramarin, Roberto
Rapidly In Situ Forming Platelet-Rich Plasma Gel Enhances Angiogenic Responses and Augments Early Wound Healing after Open Abdomen
Objective. The purposes of our present study were to evaluate the potential of platelet-rich plasma gel to enhance granulation tissue formation after open abdomen and to examine whether the effect was attributable to stimulating rapid neovascularization. Methods. Twenty-four rats underwent colon ascendens stent peritonitis surgery to induce sepsis, followed by intraperitoneal injection of nitrogen to create intra-abdominal hypertension. Four hours later, laparotomies were performed. The rats were randomized into three groups (n = 8 for each group): control, platelet-poor plasma (PPP), and platelet-rich plasma (PRP) groups. One week after the treatment, granulation tissue formation and angiogenesis were evaluated by histological and laser Doppler analysis. Results. The resultant platelet count in platelet-rich plasma was higher than that of PPP. The concentrations of platelet-derived growth factor BB, transforming growth factor ?-1, and vascular endothelial growth factor in PRP were significantly higher when compared with that of PPP. Myofibroblast count, granulation tissue thickness, vessel numbers, and blood perfusion were increased in PRP group, followed by PPP group, with control being the least. Conclusion. Rapidly in situ forming platelet-rich plasma gel promoted remarkable neovascularization and early wound healing after open abdomen and may lead to novel and effective treatments for open abdominal wounds.
Wu, Yin; Hu, Dong; Gu, Guosheng; Li, Jieshou
Immunosuppressive prednisolone enhances early cholangiocarcinoma in Syrian hamsters with liver fluke infection and administration of N-nitrosodimethylamine.
Chronic infection with Opisthorchis viverrini for many years has been associated with the development of hepatobiliary diseases including cholangiocarcinoma. It is well known that inflammation is a key component of the tumor microenvironment, and that chronic inflammation plays an important role in tumorigenesis. Therefore, in this study cholangiocarcinogenesis was induced in Syrian hamsters in order to observe the cancer-related inflammation. The Syrian hamsters were divided into 5 groups: uninfected controls; normal Syrian hamsters infected with O. viverrini (OV); immunosuppressed Syrian hamsters infected with O. viverrini (OVis); normal Syrian hamsters infected with O. viverrini and administered N-nitrosodimethylamine (CCA); and immunosuppressed Syrian hamsters infected with O. viverrini and administered N-nitrosodimethylamine (CCAis). Syrian hamster livers were later observed for gross pathology and histopathological changes; COX2 was analyzed by immunohistochemical staining. We found a decreased number of inflammatory cells surrounding the hepatic bile duct in the OVis group, but not in the OV and CCAis groups. However, in the CCAis group (with suppressed immunity) early appearance and greater severity of cholangiocarcinoma were observed; gross pathological examination revealed many cancer nodularities on the liver surface, and histopathological studies showed the presence of cancer cells, findings which correlated with the predominant expression of COX2. The present study suggests that host immune responses are intended to ameliorate pathology, and they are also crucially associated with pathogenesis in O. viverrini infection; the unbalancing of host immunity may enhance cancer-related inflammation. PMID:22851165
Juasook, Amornrat; Boonmars, Thidarut; Wu, Zhiliang; Loilome, Watcharin; Veteewuthacharn, Kulathida; Namwat, Nissana; Sudsarn, Pakkayanee; Wonkchalee, Orasa; Sriraj, Pranee; Aukkanimart, Ratchadawan
Detection of transgene in early developmental stage by GFP monitoring enhances the efficiency of genetic transformation of pepper.
In order to establish a reliable and highly efficient method for genetic transformation of pepper, a monitoring system featuring GFP (green fluorescent protein) as a report marker was applied to Agrobacterium-mediated transformation. A callus-induced transformation (CIT) system was used to transform the GFP gene. GFP expression was observed in all tissues of T(0), T(1) and T(2) peppers, constituting the first instance in which the whole pepper plant has exhibited GFP fluorescence. A total of 38 T(0) peppers were obtained from 4,200 explants. The transformation rate ranged from 0.47 to 1.83% depending on the genotype, which was higher than that obtained by CIT without the GFP monitoring system. This technique could enhance selection power by monitoring GFP expression at the early stage of callus in vitro. The detection of GFP expression in the callus led to successful identification of the shoot that contained the transgene. Thus, this technique saved lots of time and money for conducting the genetic transformation process of pepper. In addition, a co-transformation technique was applied to the target transgene, CaCS (encoding capsaicinoid synthetase of Capsicum) along with GFP. Paprika varieties were transformed by the CaCS::GFP construct, and GFP expression in callus tissues of paprika was monitored to select the right transformant. PMID:21837254
Jung, Min; Shin, Sun Hee; Park, Jeong Mi; Lee, Sung Nam; Lee, Mi Yeon; Ryu, Ki Hyun; Paek, Kee Yoeup; Harn, Chee Hark
Early molecular imaging of interstitial changes in patients after myocardial infarction: Comparison with delayed contrast-enhanced magnetic resonance imaging
Introduction The clinical feasibility of noninvasive imaging of interstitial alterations after myocardial infarction (MI) was assessed using a technetium-99m-labeled RGD imaging peptide (RIP). In experimental studies, RIP has been shown to target integrins associated with collagen-producing myofibroblasts (MFB). Methods and Results Ten patients underwent myocardial perfusion imaging (MPI) within the first week after MI. At 3 and 8 weeks after MI, RIP was administered intravenously and SPECT images acquired for interstitial imaging. RIP imaging was compared to initial MPI and to the extent of scar formation defined by late gadolinium-enhanced (LGE) cardiac magnetic resonance (CMR) imaging 1 year after MI. RIP uptake was observed in 7 of the 10 patients at both 3 and 8 weeks. Although, RIP uptake corresponded to areas of perfusion defects, it usually extended beyond the infarct zone to a variable extent; 2 of 7 patients showed tracer uptake throughout myocardium. In all positive cases, RIP uptake was similar to the extent of scar observed at 1 year by LGE-CMR imaging. Conclusion This study demonstrates that RGD-based imaging early after MI may predict the eventual extent of scar formation, which often exceeds initial MPI deficit but colocalizes with LGE in CMR imaging performed subsequently.
Verjans, Johan; Wolters, Sander; Laufer, Ward; Schellings, Mark; Lax, Michelle; Lovhaug, Dagfinn; Boersma, Hendrikus; Kemerink, Gerrit; Schalla, Simon; Gordon, Paul; Teule, Jaap
Plasma endothelin and early coronary endothelial dysfunction in recipients of a cardiac transplant
Serotonin constricts coronary arteries with endothelial dysfunction, possibly through reduced endothelial release of nitric oxide or enhanced production of constricting factors such as endothelin. Because the plasma levels of this peptide are increased in the early months after cardiac transplantation, we assessed whether a coronary hypersensitivity to the vasoconstrictor effect of serotonin is associated with high plasma endothelin levels. One
Guy Berkenboom; Christophe Giot; Philippe Unger; Jean-Luc Vachiery; Martine Antoine; Jean-Louis Leclerc
Difference between pre-operative and cardiopulmonary bypass mean arterial pressure is independently associated with early cardiac surgery-associated acute kidney injury
BACKGROUND: Cardiac surgery-associated acute kidney injury (CSA-AKI) contributes to increased morbidity and mortality. However, its pathophysiology remains incompletely understood. We hypothesized that intra-operative mean arterial pressure (MAP) relative to pre-operative MAP would be an important predisposing factor for CSA-AKI. METHODS: We performed a prospective observational study of 157 consecutive high-risk patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The primary
Hussein D Kanji; Costas J Schulze; Marilou Hervas-Malo; Peter Wang; David B Ross; Mohamad Zibdawi; Sean M Bagshaw
Late Rather Than Early Onset Bubbles in the Pulmonary Artery During Altitude Exposures Correlate Better with the Onset of "Pain-Only" Decompression Illness
NASA Technical Reports Server (NTRS)
Mechanistic insight about "pain-only" decompression illness (DCI) is limited given indirect information about venous gas emboli (VGE) detected in the pulmonary artery with Doppler ultrasound. However, we show that VGE first detected late in an altitude exposure are closely associated with subsequent symptom onset. Knowing that VGE occur late is an indication that a symptom will occur soon, but this is not a sufficient condition to guarantee that a symptom will occur.
Conkin, J.; Gernhardt, M. L.; Powell, M. R.
Early-Onset Osteoarthritis, Charcot-Marie-Tooth Like Neuropathy, Autoimmune Features, Multiple Arterial Aneurysms and Dissections: An Unrecognized and Life Threatening Condition
Background Severe osteoarthritis and thoracic aortic aneurysms have recently been associated with mutations in the SMAD3 gene, but the full clinical spectrum is incompletely defined. Methods All SMAD3 gene mutation carriers coming to our centre and their families were investigated prospectively with a structured panel including standardized clinical workup, blood tests, total body computed tomography, joint X-rays. Electroneuromyography was performed in selected cases. Results Thirty-four SMAD3 gene mutation carriers coming to our centre were identified and 16 relatives were considered affected because of aortic surgery or sudden death (total 50 subjects). Aortic disease was present in 72%, complicated with aortic dissection, surgery or sudden death in 56% at a mean age of 45 years. Aneurysm or tortuosity of the neck arteries was present in 78%, other arteries were affected in 44%, including dissection of coronary artery. Overall, 95% of mutation carriers displayed either aortic or extra-aortic arterial disease. Acrocyanosis was also present in the majority of patients. Osteoarticular manifestations were recorded in all patients. Joint involvement could be severe requiring surgery in young patients, of unusual localization such as tarsus or shoulder, or mimicking crystalline arthropathy with fibrocartilage calcifications. Sixty eight percent of patients displayed neurological symptoms, and 9 suffered peripheral neuropathy. Electroneuromyography revealed an axonal motor and sensory neuropathy in 3 different families, very evocative of type II Charcot-Marie-Tooth (CMT2) disease, although none had mutations in the known CMT2 genes. Autoimmune features including Sjogren's disease, rheumatoid arthritis, Hashimoto's disease, or isolated autoantibodies- were found in 36% of patients. Interpretation SMAD3 gene mutations are associated with aortic dilatation and osteoarthritis, but also autoimmunity and peripheral neuropathy which mimics type II Charcot-Marie-Tooth.
Aubart, Melodie; Gobert, Delphine; Aubart-Cohen, Fleur; Detaint, Delphine; Hanna, Nadine; d'Indya, Hyacintha; Lequintrec, Janine-Sophie; Renard, Philippe; Vigneron, Anne-Marie; Dieude, Philippe; Laissy, Jean-Pierre; Koch, Pierre; Muti, Christine; Roume, Joelle; Cusin, Veronica; Grandchamp, Bernard; Gouya, Laurent; LeGuern, Eric; Papo, Thomas; Boileau, Catherine; Jondeau, Guillaume
The arterial switch operation before Jatene.
Attempts at the arterial switch operation predated the Senning and the Mustard venous switch procedures. No patients survived the earlier arterial switch methods. Therefore, from the 1960s to the 1980s, venous switch surgeries became the dominant treatment method for transposition of the great arteries. The Brazilian cardiac surgeon, Adib Jatene, reported the first successful arterial switch in 1975. The history of the earlier arterial switches performed in the 1950s and 1960s is not well known. This article discusses that early history. PMID:18709398
Evans, W N
A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: II. In vivo results
NASA Astrophysics Data System (ADS)
Accurate quantification of pharmacokinetic model parameters in tracer kinetic imaging experiments requires correspondingly accurate determination of the arterial input function (AIF). Despite significant effort expended on methods of directly measuring patient-specific AIFs in modalities as diverse as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), dynamic positron emission tomography (PET), and perfusion computed tomography (CT), fundamental and technical difficulties have made consistent and reliable achievement of that goal elusive. Here, we validate a new algorithm for AIF determination, the Monte Carlo blind estimation (MCBE) method (which is described in detail and characterized by extensive simulations in a companion paper), by comparing AIFs measured in DCE-MRI studies of eight brain tumor patients with results of blind estimation. Blind AIFs calculated with the MCBE method using a pool of concentration-time curves from a region of normal brain tissue were found to be quite similar to the measured AIFs, with statistically significant decreases in fit residuals observed in six of eight patients. Biases between the blind and measured pharmacokinetic parameters were the dominant source of error. Averaged over all eight patients, the mean biases were +7% in K trans, 0% in kep, -11% in vp and +10% in ve. Corresponding uncertainties (median absolute deviation from the best fit line) were 0.0043?min-1 in K trans, 0.0491 min-1 in kep, 0.29% in vp and 0.45% in ve. The use of a published population-averaged AIF resulted in larger mean biases in three of the four parameters (-23% in K trans, -22% in kep, -63% in vp), with the bias in ve unchanged, and led to larger uncertainties in all four parameters (0.0083 min-1 in K trans, 0.1038 min-1 in kep, 0.31% in vp and 0.95% in ve). When blind AIFs were calculated from a region of tumor tissue, statistically significant decreases in fit residuals were observed in all eight patients despite larger deviations of these blind AIFs from the measured AIFs. The observed decrease in root-mean-square fit residuals between the normal brain and tumor tissue blind AIFs suggests that the local blood supply in tumors is measurably different from that in normal brain tissue and that the proposed method is able to discriminate between the two. We have shown the feasibility of applying the MCBE algorithm to DCE-MRI data acquired in brain, finding generally good agreement with measured AIFs and decreased biases and uncertainties relative to the use of a population-averaged AIF. These results demonstrate that the MCBE algorithm is a useful alternative to direct AIF measurement in cases where acquisition of high-quality arterial input function data is difficult or impossible.
Schabel, Matthias C.; DiBella, Edward V. R.; Jensen, Randy L.; Salzman, Karen L.
Smokeless tobacco extracts modulate exogenous gene expression in early passage cultured human oral epithelial cells: an in vitro system to study chemical and viral enhancer/promoter interaction.
The increased risk for cancers of the oral cavity from smokeless tobacco use may reflect the interaction of tobacco with genetic factors, such as oncogenes, and other exogenous factors, such as viruses. An in vitro system was developed based on expression of the chloramphenicol acetyltransferase (CAT) reporter gene to study interactions of chemical treatments with viral enhancer/promoters in early passage cell cultures of oral cavity-derived epithelial cells. Expression of CAT in transfected cells was significantly greater with CAT under the control of the cytomegalovirus immediate early enhancer/promoter (pCEP4/CAT) compared to the Rous sarcoma virus long terminal repeat enhancer/promoter (pRSV-cat) and the simian virus 40 (SV40) early promoter (pSV2-cat). No CAT expression was detected using corresponding control plasmids without the CAT reporter gene. Using this system, smokeless tobacco extracts prepared from either dry snuff or moist snuff delayed maximum CAT expression from Day 4 to Day 5, with sustained, significantly increased CAT expression at 12 days compared to the declining CAT expression observed in untreated control cells. Smokeless tobacco extracts can modulate intracellular gene expression. This system provides an in vitro model to test specificity of toxic agents on enhancer/promoter activity and the interaction on exogenous gene expression. PMID:11395331
Demirci, C S; Miller, D R; Baillargeon, J; Moyer, M P; Jenson, H B
Scar extent evaluated by late gadolinium enhancement CMR: a powerful predictor of long term appropriate ICD therapy in patients with coronary artery disease
Background Coronary artery disease (CAD) patients are at risk for life-threatening ventricular arrhythmias (VA) related to scar tissue. Late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) can accurately identify myocardial scar extent. It has been shown that scar extent, particularly scar transmurality, percent scar and scar mass, are associated with the occurrence of appropriate implantable cardioverter-defibrillator (ICD) therapy. However, quantification of transmurality extent has never been studied. The purpose of our study was to evaluate whether different methods quantifying scar transmurality, percent scar and scar mass (assessed with LGE-CMR) can predict appropriate ICD therapy in CAD patients with a long term follow-up period. Methods and results We enrolled retrospectively 66 patients with chronic CAD referred for primary or secondary preventive ICD implantation and LGE-CMR before ICD implantation. Using LGE-CMR, scar extent was assessed by measuring scar mass, percent scar and transmural scar extent using four different methods. The median follow-up duration was 41.5 months (interquartile range 22–52). The endpoint was the occurrence of appropriate device therapy and occurred in 14 patients. Pre-ICD revascularization and transmural scar extent were significantly associated with the study endpoint but the latter was especially highly dependent on the method used. Patients with appropriate device therapy had also larger scar mass (29.6 ± 14.5 g vs 17.1 ± 8.8 g, p = 0.004), and larger percent scar (15.1 ± 8.2% vs 9.9 ± 5.6%, p = 0.03) than patients without appropriate device therapy. In multivariate analysis, scar extent variables remained significantly associated with the study end-point. Conclusions In this study of CAD patients implanted for primary or secondary preventive ICD, pre-ICD revascularization and scar extent studied by LGE-CMR were significantly associated with appropriate device therapy and can identify a subgroup of CAD patients with an increased risk of life-threatening VA. Depending of the method used, transmural scar extent may vary significantly and needs further studies to obtain a validated and consensual study method.
NOS Inhibition Enhances Myogenic Tone by Increasing Rho-Kinase Mediated Ca2+ Sensitivity in the Male but Not the Female Gerbil Spiral Modiolar Artery
Cochlear blood flow regulation is important to prevent hearing loss caused by ischemia and oxidative stress. Cochlear blood supply is provided by the spiral modiolar artery (SMA). The myogenic tone of the SMA is enhanced by the nitric oxide synthase (NOS) blocker L-NG-Nitro-Arginine (LNNA) in males, but not in females. Here, we investigated whether this gender difference is based on differences in the cytosolic Ca2+ concentration and/or the Ca2+ sensitivity of the myofilaments. Vascular diameter, myogenic tone, cytosolic Ca2+, and Ca2+ sensitivity were evaluated in pressurized SMA segments isolated from male and female gerbils using laser-scanning microscopy and microfluorometry. The gender difference of the LNNA-induced tone was compared, in the same vessel segments, to tone induced by 150 mM K+ and endothelin-1, neither of which showed an apparent gender-difference. Interestingly, LNNA-induced tone in male SMAs was observed in protocols that included changes in intramural pressure, but not when the intramural pressure was held constant. LNNA in male SMAs did not increase the global Ca2+ concentration in smooth muscle cells but increased the Ca2+ sensitivity. This increase in the Ca2+ sensitivity was abolished in the presence of the guanylyl cyclase inhibitor ODQ or by extrinsic application of either the nitric oxide (NO)-donor DEA-NONOate or the cGMP analog 8-pCPT-cGMP. The rho-kinase blocker Y27632 decreased the basal Ca2+ sensitivity and abolished the LNNA-induced increase in Ca2+ sensitivity in male SMAs. Neither LNNA nor Y27632 changed the Ca2+ sensitivity in female SMAs. The data suggest that the gender difference in LNNA-induced tone is based on a gender difference in the regulation of rho-kinase mediated Ca2+ sensitivity. Rho-kinase and NO thus emerge as critical factors in the regulation of cochlear blood flow. The larger role of NO-dependent mechanisms in male SMAs predicts greater restrictions on cochlear blood flow under conditions of impaired endothelial cell function.
Wangemann, Philine
... ventilator (respirator; breathing machine) settings. The blood oxygen pressure measures from an arterial line give more detailed information than that from a pulse oximeter (a sensor that is clipped on to a patient's finger, ...
... MRI of the arm or leg Myocardial contrast echocardiography (MCE) Plethysmography Transcranial Doppler exam of arteries to the brain Transesophageal echocardiography (TEE) This disease may also affect the results ...
Enhancement of voltage-gated k+ channels and depression of voltage-gated Ca2+ channels are involved in quercetin-induced vasorelaxation in rat coronary artery.
Quercetin is one of the most common flavonoids in the human daily diet. Its affects the coronary artery, especially L-type voltage-gated Ca2+ channels and voltage-gated K+ channels in the arterial smooth muscle cells, which are poorly understood. The present experiments were designed to study the myogenic effect of quercetin and its possible underlying mechanisms in the rat coronary artery. A wire myograph was used to observe the myogenic effects. Arterial smooth muscle cells were freshly isolated from the rat coronary artery and the intracellular free Ca2+ concentration was measured with molecular probe fluo-4-AM. The effects of quercetin on L-type voltage-gated Ca2+ channels and voltage-gated K+ channels were studied using a whole-cell patch clamp. Quercetin (3-30?µM) produced a depression and relaxation on the contraction induced by KCl or the thromboxane A2 analog 9,11-Dideoxy-9?,11?-methanoepoxy prostaglandin F 2? . The vasorelaxation was attenuated by 4-aminopyridine, a specific voltage-gated K+ channel inhibitor, but was not affected by the NG-nitro-L-arginine methylester ester (a nitric oxide synthesis inhibitor), glibenclamide (a ATP-activated K+ channel inhibitor), iberiotoxin (a Ca2+-activated K+ channel inhibitor), BaCl2 (an inward rectifier K+ channel inhibitor), or by endothelium denudation. At the same concentrations, quercetin reduced the KCl-induced elevation of the intracellular free Ca2+ concentration, inhibited the inward Ca2+ currents through L-type voltage-gated Ca2+ channels, and increased the outward K+ currents through voltage-gated K+ channels in the rat coronary artery smooth muscle cells. Collectively, our results demonstrate that quercetin possesses vasospasmolytic effects in RCA and suggest that depression of the Ca2+ influx through L-type voltage-gated Ca2+ channels and augmentation of voltage-gated K+ channel activity in the myocytes may underlie coronary relaxation. PMID:24710898
Hou, Xiaomin; Liu, Yu; Niu, Longgang; Cui, Lijuan; Zhang, Mingsheng
Widespread DNA hypomethylation at gene enhancer regions in placentas associated with early-onset pre-eclampsia
Pre-eclampsia is a serious complication of pregnancy that can affect both maternal and fetal outcomes. Early-onset pre-eclampsia (EOPET) is a severe form of pre-eclampsia that is associated with altered physiological characteristics and gene expression in the placenta. DNA methylation is a relatively stable epigenetic modification to DNA that can reflect gene expression, and can provide insight into the mechanisms underlying such expression changes. This case–control study focused on DNA methylation and gene expression of whole chorionic villi samples from 20 EOPET placentas and 20 gestational age-matched controls from pre-term births. DNA methylation was also assessed in placentas affected by late-onset pre-eclampsia (LOPET) and normotensive intrauterine growth restriction (nIUGR). The Illumina HumanMethylation450 BeadChip was used to assess DNA methylation at >480 000 cytosine-guanine dinucleotide (CpG) sites. The Illumina HT-12v4 Expression BeadChip was used to assess gene expression of >45 000 transcripts in a subset of cases and controls. DNA methylation analysis by pyrosequencing was used to follow-up the initial findings in four genes with a larger cohort of cases and controls, including nIUGR and LOPET placentas. Bioinformatic analysis was used to identify overrepresentation of gene ontology categories and transcription factor binding motifs. We identified 38 840 CpG sites with significant (false discovery rate <0.01) DNA methylation alterations in EOPET, of which 282 had >12.5% methylation difference compared with the controls. Significant sites were enriched at the enhancers and low CpG density regions of the associated genes and the majority (74.5%) of these sites were hypomethylated in EOPET. EOPET, but not associated clinical features, such as intrauterine growth restriction (IUGR), presented a distinct DNA methylation profile. CpG sites from four genes relevant to pre-eclampsia (INHBA, BHLHE40, SLC2A1 and ADAM12) showed different extent of changes in LOPET and nIUGR. Genome-wide expression in a subset of samples showed that some of the gene expression changes were negatively correlated with DNA methylation changes, particularly for genes that are responsible for angiogenesis (such as EPAS1 and FLT1). Results could be confounded by altered cell populations in abnormal placentas. Larger sample sizes are needed to fully address the possibility of sub-profiles of methylation within the EOPET cohort. Based on DNA methylation profiling, we conclude that there are widespread DNA methylation alterations in EOPET that may be associated with changes in placental function. This property may provide a useful tool for early screening of such placentas. This study identifies DNA methylation changes at many loci previously reported to have altered gene expression in EOPET placentas, as well as in novel biologically relevant genes we confirmed to be differentially expressed. These results may be useful for DNA- methylation-based non-invasive prenatal diagnosis of at-risk pregnancies.
Blair, John D.; Yuen, Ryan K.C.; Lim, Brendan K.; McFadden, Deborah E.; von Dadelszen, Peter; Robinson, Wendy P.
Preradiotherapy Calcium Scores of the Coronary Arteries in a Cohort of Women With Early-Stage Breast Cancer: A Comparison With a Cohort of Healthy Women
Purpose: Breast cancer radiotherapy has been associated with an increased risk of cardiac toxicity. However, no data are available on the probability of developing coronary artery disease (CAD) in breast cancer patients when compared with healthy women. Therefore, baseline coronary artery calcium (CAC) scores, as an accepted tool to predict CAD, were determined and compared with the CAC scores of a healthy, asymptomatic cohort, the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Methods and Materials: Eighty consecutive patients with ductal carcinoma in situ or infiltrative breast cancer referred for radiotherapy after breast-conserving surgery were included in our study. Their cardiovascular risk profile was registered, and a 64 multislice CT scan was performed. The CAC scores of an unselected (Caucasian only) Radiotherapy Centre West (RCWEST) cohort, as well as of those of a selected (comorbidity and race adjusted) RCWEST cohort, were determined. The scores of both cohorts were compared with those of the female (Caucasian only) MESA cohort. Results: For the unselected RCWEST cohort (n = 62) we found significant (p < .01) higher scores for women in the 55-64 age category compared with those of the MESA cohort. In the selected cohort (n = 55) the CAC scores of the women in the age category 55-64 were significantly (p = .02) higher compared with the MESA cohort. No significant differences were noted in the other age categories. Conclusion: Both cohorts revealed that CAC scores in the 55-64 age category were significantly higher than the CAC scores in the asymptomatic (female) MESA population. These data suggest that breast cancer patients bear a higher risk of developing coronary heart disease before the start of radiotherapy. Therefore, measures to decrease cardiac dose further in breast cancer radiotherapy are even more important.
Mast, Mirjam E., E-mail: email@example.com [Radiotherapy Centre West, The Hague (Netherlands); Heijenbrok, Mark W. [Department of Radiology, Medical Center Haaglanden, The Hague (Netherlands); Petoukhova, Anna L. [Radiotherapy Centre West, The Hague (Netherlands); Scholten, Astrid N. [Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands); Schreur, Joop H.M. [Department of Cardiology, Medical Center Haaglanden, The Hague (Netherlands); Struikmans, Henk [Radiotherapy Centre West, The Hague (Netherlands); Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands)
Nitrate reductase-mediated early nitric oxide burst alleviates oxidative damage induced by aluminum through enhancement of antioxidant defenses in roots of wheat (Triticum aestivum).
• Nitric oxide (NO) is an important signaling molecule involved in the physiological processes of plants. The role of NO release in the tolerance strategies of roots of wheat (Triticum aestivum) under aluminum (Al) stress was investigated using two genotypes with different Al resistances. • An early NO burst at 3 h was observed in the root tips of the Al-tolerant genotype Jian-864, whereas the Al-sensitive genotype Yang-5 showed no NO accumulation at 3 h but an extremely high NO concentration after 12 h. Stimulating NO production at 3 h in the root tips of Yang-5 with the NO donor relieved Al-induced root inhibition and callose production, as well as oxidative damage and ROS accumulation, while elimination of the early NO burst by NO scavenger aggravated root inhibition in Jian-864. • Synthesis of early NO in roots of Jian-864 was mediated through nitrate reductase (NR) but not through NO synthase. Elevated antioxidant enzyme activities were induced by Al stress in both wheat genotypes and significantly enhanced by NO donor, but suppressed by NO scavenger or NR inhibitor. • These results suggest that an NR-mediated early NO burst plays an important role in Al resistance of wheat through modulating enhanced antioxidant defense to adapt to Al stress. PMID:24237306
Sun, Chengliang; Lu, Lingli; Liu, Lijuan; Liu, Wenjing; Yu, Yan; Liu, Xiaoxia; Hu, Yan; Jin, Chongwei; Lin, Xianyong
Expression of NADPH oxidases and enhanced H 2O 2-generating activity in human coronary artery endothelial cells upon induction with tumor necrosis factor-?
Tumor necrosis factor (TNF)-?, which potentiates reactive oxygen species (ROS) generation, is crucial for the development of coronary arteritis and aneurysm in Kawasaki disease. We hypothesized that vascular NADPH oxidase (Nox) enzymes participate in the TNF-?-triggered endothelial damage through elevating ROS generation. Thus, we herein examine the expression of Nox enzymes in human coronary artery endothelial cells (HCAEC) and the
Lucia S. Yoshida; Shohko Tsunawaki
Detection of neuroendocrine tumours in the small intestines using contrast-enhanced multiphase Ga-68 DOTATOC PET/CT: the potential role of arterial hyperperfusion
Background Interpretation of small intestinal neuroendocrine tumours (NETs) by Ga-68 DOTATOC PET/CT can be difficult. The potential benefit of arterial hyperperfusion for the detection of NETs was evaluated. Methods Between 2006 and 2009, 320 consecutive Ga-68 DOTATOC PET/CT examinations, performed for NETs, revealed 40 lesions suggesting intestinal NETs in 25 patients. Two groups of lesions were distinguished: epigastric lesions evaluable in the arterial and venous CT scan (Group 1) and hypogastrial lesions evaluable in the venous CT scan only (Group 2). Lesions were jointly rated by two radiologists and a nuclear medicine physician. Maximum standard uptake values (SUVmax) of lesions and background were assessed. The reference standard was histology (available for 28 lesions) or follow-up (for a mean of 22.9 months). Results PET detected all suspicious lesions but was false positive in 3 lesions. In Group 1 the arterial scan performed significantly better than the venous scan (p = 0.008). Diagnostic performance was better in Group 1 than in Group 2 (p < 0.001). SUVmax of true positive lesions were significantly higher than background SUVmax (p < 0.001) and SUVmax of false positive lesions (p = 0.005). Conclusions The arterial phase of multiphase Ga-68 DOTATOC PET/CT might improve the localization of intestinal NETs and, thereby, improve the overall diagnostic accuracy of this modality in the assessment of intestinal NETs by adding information about lesion perfusion not available when only venous CT is performed.
Schreiter, Nils F.; Maurer, Martin; Pape, Ulrich-Frank; Hamm, Bernd; Brenner, Winfried; Froeling, Vera
Arterial grafts: clinical classification and pharmacological management.
In comparison with standard saphenous vein grafts, use of the internal mammary artery (IMA) as a coronary artery bypass graft has achieved superior long-term results. This is related to the differences in the biological characteristics between the venous and arterial grafts. However, even arterial grafts are not uniform in their biological characteristics. The variation in the perioperative behavior of the grafts and in their long-term patency may be related to different characteristics. These factors should be taken into account in the use of arterial grafts, some of which are subjected to more active pharmacological intervention during and after the operation to obtain satisfactory results. To better understand the biological behavior of the grafts, their common features and their differences, a clinical classification may be useful for a practicing surgeon. Based on experimental studies of their vasoreactivity combined with anatomical, physiological and embryological considerations, we have proposed a functional classification for arterial grafts that may be useful clinically. Our classification suggests that there are three types of arterial grafts: Type I-somatic arteries; Type II-splanchnic arteries; and Type III-limb arteries. Type I arteries have enhanced endothelial function and release more nitric oxide and other relaxing factors. Type II arteries, such as the gastro-epiploic artery, and Type III arteries, such as the radial artery (RA), have higher pharmacological reactivity to vasoconstrictors. This classification explains why the IMA has the best long-term patency. Because Type II and III arteries are prone to spasms due to higher contractility, they require more active pharmacological interventions. Furthermore, the harvesting technique of the conduits, including the saphenous vein and IMA, are described and discussed in this article. Prevention of spasms using two cocktails of medications (verapamil + nitroglycerin and nicardipine + nitroglycerin) during harvesting of the conduits is described. These solutions have been demonstrated to be clinically effective. PMID:23977630
He, Guo-Wei
Arterial stiffness, central hemodynamics, and cardiovascular risk in hypertension.
This review summarizes several scientific contributions at the recent Satellite Symposium of the European Society of Hypertension, held in Milan, Italy. Arterial stiffening and its hemodynamic consequences can be easily and reliably measured using a range of noninvasive techniques. However, like blood pressure (BP) measurements, arterial stiffness should be measured carefully under standardized patient conditions. Carotid-femoral pulse wave velocity has been proposed as the gold standard for arterial stiffness measurement and is a well recognized predictor of adverse cardiovascular outcome. Systolic BP and pulse pressure in the ascending aorta may be lower than pressures measured in the upper limb, especially in young individuals. A number of studies suggest closer correlation of end-organ damage with central BP than with peripheral BP, and central BP may provide additional prognostic information regarding cardiovascular risk. Moreover, BP-lowering drugs can have differential effects on central aortic pressures and hemodynamics compared with brachial BP. This may explain the greater beneficial effect provided by newer antihypertensive drugs beyond peripheral BP reduction. Although many methodological problems still hinder the wide clinical application of parameters of arterial stiffness, these will likely contribute to cardiovascular assessment and management in future clinical practice. Each of the abovementioned parameters reflects a different characteristic of the atherosclerotic process, involving functional and/or morphological changes in the vessel wall. Therefore, acquiring simultaneous measurements of different parameters of vascular function and structure could theoretically enhance the power to improve risk stratification. Continuous technological effort is necessary to refine our methods of investigation in order to detect early arterial abnormalities. Arterial stiffness and its consequences represent the great challenge of the twenty-first century for affluent countries, and "de-stiffening" will be the goal of the next decades. PMID:22174583
Palatini, Paolo; Casiglia, Edoardo; G?sowski, Jerzy; G?uszek, Jerzy; Jankowski, Piotr; Narkiewicz, Krzysztof; Saladini, Francesca; Stolarz-Skrzypek, Katarzyna; Tikhonoff, Valérie; Van Bortel, Luc; Wojciechowska, Wiktoria; Kawecka-Jaszcz, Kalina
... Artery Disease • Overview Peripheral artery disease, or P.A.D., refers to arterial disease that occurs outside of the heart or brain. In P.A.D., the arteries that carry oxygenated blood throughout the ...
Occlusive Peripheral Arterial Disease
... Pericardial Disease Sports and the Heart Heart Tumors Atherosclerosis Coronary Artery Disease Peripheral Arterial Disease Aneurysms and ... Disease Occlusive peripheral arterial disease often results from atherosclerosis. Symptoms depend on which artery is blocked and ...
Early Risk of Mortality after Coronary Artery Revascularization in Patients with Left Ventricular Dysfunction and Potential Role of the Wearable Cardioverter Defibrillator
Background Implantable cardioverter defibrillator (ICD) implantation for prevention of sudden cardiac death is typically deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. We determined mortality risk in post-revascularization patients with left ventricular ejection fraction (LVEF) ?35% and compared survival to those discharged with a wearable cardioverter defibrillator (WCD). Methods and Results Hospital survivors after surgical (CABG) or percutaneous (PCI) revascularization with LVEF?35% were included from Cleveland Clinic and national WCD registries. Kaplan-Meier, Cox proportional hazards, propensity score-matched survival and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared to 809 with WCDs (90-day mortality post-CABG 7% vs. 3%, p=0.03; post-PCI 10% vs. 2%, p<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, p<0.0001) and both post-CABG (38%, p=0.048) and post-PCI (57%, p<0.0001) cohorts (mean follow-up 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post-CABG, p=0.002; 67% post-PCI, p<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy. Conclusions Patients with LVEF?35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard appeared less marked in WCD users, prospective studies in this high risk population are indicated to confirm whether WCD use as a bridge to LVEF improvement or ICD implantation can improve outcomes after coronary revascularization.
Zishiri, Edwin T.; Williams, Sarah; Cronin, Edmond M.; Blackstone, Eugene H.; Ellis, Stephen G.; Roselli, Eric E.; Smedira, Nicholas G.; Gillinov, A. Marc; Glad, Jo Ann; Tchou, Patrick J.; Szymkiewicz, Steven J.; Chung, Mina K.
Sex Differences in Arterial Stiffness and Ventricular-Arterial Interactions
Objectives To assess sex-differences in ventricular-arterial interactions. Background Heart failure with preserved ejection fraction (HFpEF) is more prevalent in women than men, but the basis for this difference remains unclear. Methods Echocardiography and arterial tonometry were performed to quantify arterial and ventricular stiffening and interaction in 461 participants without heart failure (189 men, age 67±9 years; 272 women, age 65±10 years). Aortic characteristic impedance (Zc), total arterial compliance (TAC, pulsatile load) and systemic vascular resistance index (SVRI, steady load) were compared between men and women, and sex-specific multivariable regression analyses were performed to assess associations of these arterial parameters with diastolic dysfunction and ventricular-arterial coupling (effective arterial elastance/left ventricular end-systolic elastance, Ea/Ees) after adjustment for potential confounders. Results Zc was higher and TAC was lower in women, whereas SVRI was similar between sexes. In women but not men, higher Zc was associated with E/A ratio (?±SE: ?0.17±0.07), diastolic dysfunction (OR 7.8; 95% CI: 2.0, 30.2) and Ea/Ees (?±SE: 0.13±0.0) (P?0.01 for all). Similarly, TAC was associated with E/A ratio (?± SE: 0.12±0.04), diastolic dysfunction (OR 0.33; 95% CI: 0.12, 0.89) and Ea/Ees (?± SE: ?0.09±0.03) in women only (P?0.03 for all). SVRI was not associated with diastolic dysfunction or Ea/Ees. Conclusions Proximal aortic stiffness (Zc) is greater in women than men, and women may be more vulnerable to the deleterious effects of greater pulsatile and early arterial load on diastolic function and ventricular-arterial interaction. This may contribute to the greater risk of HFpEF in women.
Coutinho, Thais; Borlaug, Barry A; Pellikka, Patricia A; Turner, Stephen T; Kullo, Iftikhar J
[Isolated spontaneous dissection of superior mesenteric artery: treated by percutaneous endovascular stent placement].
Isolated spontaneous dissection of the superior mesenteric artery (SMA) without aortic dissection is a rare cause of acute mesenteric ischemia. A sudden decrease of intestinal blood flow can lead to fatal complications such as ischemic necrosis, shock, and death. Therefore, early diagnosis and therapeutic approach before the occurrence of intestinal infarction are the most important factor to determine the patients prognosis. A 52-year-old male presented with postprandial periumbilical pain, and isolated spontaneous dissection of the superior mesenteric artery with mural thrombus was detected by abdominal computed tomography with contrast enhancement. By the percutaneous implantation of vascular metallic stent via femoral artery, he was treated successfully. We report a case of isolated spontaneous dissection of the SMA treated by a percutaneous endovascular stent replacement with a review of literature. PMID:20098068
Kwak, Jae Wuk; Paik, Chang Nyol; Lee, Kang Moon; Chung, Woo Chul; Jung, Sung Hoon; Kim, Ji Eun; Baik, Jun Hyun; Yang, Jin Mo
Blockade of TGF- by Catheter-based Local Intravascular Gene Delivery Does Not Alter The In-Stent Neointimal Response, But Enhances Inflammation in Pig Coronary Arteries
Background Extracellular matrix (ECM) accumulation significantly contributes to in-stent restenosis. In this regard, transforming growth factor (TGF)-?, a positive regulator of ECM deposition, may be implicated in in-stent restenosis. The goal of this study was to assess the effect of blockade of TGF-? on stent-induced restenosis in porcine coronary arteries. Methods An adenovirus expressing the ectodomain of the TGF-? type II receptor (AdT?-ExR) was applied onto a coronary arterial segment of a pig (n=10) using an Infiltrator™, followed by stent deployment. Controls consisted of adenoviruses expressing ?-galactosidase (AdLacZ) or phosphate-buffered saline (PBS) applied onto the other segment (n=10) of the same pig. Results Computer-based pathological morphometric analysis of stented coronary arteries, performed 4 weeks after stenting, demonstrated no significant difference in morphometric parameters such as in-stent neointimal area and % area stenosis between the AdT?-ExR group and control (n=7 for each). However the AdT?-ExR group had increased neointimal cell density, infiltration of inflammatory cells mostly consisting of CD3+ T cell, accumulation of hyaluronan, cell proliferation rate, and adventitial matrix metalloproteinase-1 (MMP-1) expression compared with control. The expression of connective tissue growth factor mRNA, measured by reverse transcription PCR, in cultured rat arterial smooth muscle cells was inhibited by AdT?-ExR at moi 60. Conclusions Blockade of TGF-? by catheter based local intravascular gene delivery does not reduce stent-induced neointima formation 4 weeks after stenting in spite of modest inhibition of ECM accumulation, but it induces vascular inflammation and associated pathological changes that may potentially aggravate lesion progression.
Chung, Ick-Mo; Kim, Junwoo; Pak, Youngmi K; Jang, Yangsoo; Yang, Woo-Ick; Han, Innoc; Park, Seung-Jung; Park, Seong-Wook; Huh, Jooryung; Wight, Thomas N; Ueno, Hikaru
Histamine-Induced Production of Interleukin6 and Interleukin8 by Human Coronary Artery Endothelial Cells Is Enhanced by Endotoxin and Tumor Necrosis Factor-?
In this study, we tested the synergy between histamine and LPS, and histamine and TNF-?, on endothelial cell production of interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemoattractant protein-1 (MCP-1). Human coronary artery endothelial cells (HCAEC) were cultured in vitro with histamine (0.1 to 1000 ?M) in the presence or absence of LPS or TNF-? for 24 h, and the secreted
Yuai Li; Luqi Chi; Daniel J. Stechschulte; Kottarappat N. Dileepan
Basic Fibroblast Growth Factor Release by Human Coronary Artery Endothelial Cells Is Enhanced by Matrix Proteins, 17?-Estradiol, and a PKC Signaling Pathway
Endothelial cell function is regulated by interactions among cells, the extracellular matrix (ECM), and soluble mediators. We investigated this interaction by examining the effect of 17?-estradiol (E2) on release of basic fibroblast growth factor (FGF-2) by human coronary artery endothelial cells (HCAEC) cultured on ECM proteins. After estrogen-depleted HCAEC were treated with E2 for 2 h, the conditioned media and
Maria Luiza C. Albuquerque; Steven K. Akiyama; H. William Schnaper
Enhanced discrimination of calcified and soft arterial plaques using computed tomography with a multi-energy-window photon counting x-ray detector
This work aims at discriminating between soft and calcified coronary artery plaques using microCT with a multi-energywindow photon counting X-ray detector (PCXD). We have previously investigated a solid state X-ray detector which has the capability to count individual photons in different energy windows. The data from these energy windows may be treated as multiple simultaneous X-ray acquisitions within non-overlapping energy
Xiaolan Wang; Jingyan Xu; Katsuyuki Taguchi; Bradley E. Patt; Douglas J. Wagenaar; Eric C. Frey
Chronic hypoxia upregulates pulmonary arterial ASIC1: a novel mechanism of enhanced store-operated Ca2+ entry and receptor-dependent vasoconstriction
Acid-sensing ion channel 1 (ASIC1) is a newly characterized contributor to store-operated Ca2+ entry (SOCE) in pulmonary vascular smooth muscle (VSM). Since SOCE is implicated in elevated basal VSM intracellular Ca2+ concentration ([Ca2+]i) and augmented vasoconstriction in chronic hypoxia (CH)-induced pulmonary hypertension, we hypothesized that ASIC1 contributes to these responses. To test this hypothesis, we examined effects of the specific pharmacologic ASIC1a inhibitor, psalmotoxin 1 (PcTX1), on vasoconstrictor and vessel wall [Ca2+]i responses to UTP and KCl (depolarizing stimulus) in fura-2-loaded, pressurized small pulmonary arteries from control and CH (4 wk at 0.5 atm) Wistar rats. PcTX1 had no effect on basal vessel wall [Ca2+]i, but attenuated vasoconstriction and increases in vessel wall [Ca2+]i to UTP in arteries from control and CH rats; normalizing responses between groups. In contrast, responses to the depolarizing stimulus, KCl, were unaffected by CH exposure or PcTX1. Upon examining potential Ca2+ influx mechanisms, we found that PcTX1 prevented augmented SOCE following CH. Exposure to CH resulted in a significant increase in pulmonary arterial ASIC1 protein. This study supports a novel role of ASIC1 in elevated receptor-stimulated vasoconstriction following CH which is likely mediated through increased ASIC1 expression and SOCE.
Herbert, Lindsay M.; Walker, Benjimen R.; Resta, Thomas C.
Neighborhood contexts experienced by young Mexican-American women: enhancing our understanding of risk for early childbearing.
Young Mexican-American women are disproportionately affected by teen pregnancy and early childbearing. While many of the studies that have investigated this population's high risk for early childbearing have focused predominantly on micro-level factors, a growing body of research has demonstrated the importance of neighborhood-level factors in shaping risk for this outcome. In order to elucidate the role of neighborhood context with regards to early childbearing among adolescent Mexican-American women, it is important to understand what these young women consider to be their neighborhood context and how they experience these contexts. This study utilized a mixed-methods design incorporating participatory photography, photo-elicitation, and focus groups in order to gain a more nuanced understanding of how neighborhood context is conceptualized and experienced by Mexican-American young women, and how these experiences may influence risk for early childbearing. Major findings include: (1) participants view the blocks on which they live as their neighborhood, but their exposure to neighborhood context extends beyond these blocks and includes the transient spaces they move through daily; and (2) within their neighborhood contexts, participants are influenced by experiences of discrimination and the presence of gangs and violence. These findings point to the importance of neighborhood-level factors in the lives of adolescent Mexican-American women, and may be used to inform future studies looking at the role of neighborhood context in shaping risk for early childbearing among this population. PMID:22143409
Richardson, Dawn M; Nuru-Jeter, Amani M
Popliteal Artery Pseudoaneurysm Following Primary Total Knee Arthroplasty
An early diagnosis of popliteal artery pseudoaneurysm-a sequela of popliteal artery trauma-is difficult owing to its late presentation following total knee arthroplasty. The incidence of a popliteal artery pseudoaneurysm with a hematoma presenting only a peripheral nerve injury after total knee arthroplasty is also uncommon in the absence of common diagnostic features such as a pulsatile swelling with an audible bruit on auscultation. In the present report, we describe popliteal artery pseudoaneurysm following total knee arthroplasty.
Shin, Young-Soo; Hwang, Yeok-Gu; Savale, Abhijit Prakash
Vygotskian Perspectives on Using Dramatic Play to Enhance Children's Development and Balance Creativity with Structure in the Early Childhood Classroom
ERIC Educational Resources Information Center
What kind of environmental and administrative factors support the balance between child-centred and teacher-directed practices in the early childhood classroom? What specific aspects of children's development are nurtured by this pedagogy? These and other pedagogical issues are addressed in this article as it describes how a particular curriculum…
Gupta, Amita
High resolution benthic ( Cibicidoides spp.) stable isotope and percent sand fraction records were constructed for the early Pliocene (3.3 - 4.7 Ma) at Ocean Drilling Program (ODP) Sites 925 (3042 m water depth) and 929 (4361 m water depth). These sites are located in the modern mixing zone of North Atlantic Deep Water (NADW) and Antarctic Bottom Water (AABW).
Katharina Billups; A. Christina Ravelo; James C. Zachos
Incorporation of Polyamines in the Priming Media Enhances the Germination and Early Seedling Growth in Hybrid Sunflower (Helianthus annuus L.)
A laboratory study was conducted to evaluate the benefits (if any) associated with the incorporation of polyamines in the priming media for hybrid sunflower achene priming. Achenes were subjected to hydropriming for 24 h and in the solutions containing 10 mg L -1 spermidine and putrescine for 24 h. All the achene priming treatments resulted in improved germination and early
Enhancements to and Characterization of the Very Early Time Electromagnetic (VETEM) Prototype Instrument and Applications to Shallow Subsurface Imaging at Sites in the DOE Complex
The objective of this research is to enhance the state-of-the-art in electromagnetic imaging of the shallow subsurface in electrically conductive media where groundpenetrating radar (GPR) provides insufficient penetration and time domain electromagnetic (TDEM) systems provide insufficient resolution. This objective is being pursued by instrumentation enhancements to the existing very early time electromagnetic (VETEM) system coupled with physical and numerical modeling. Success in this endeavor will improve the speed and accuracy of waste pit and trench location and characterization, and could have additional applications to shallow DNAPL and LNAPL spill and cleanup monitoring, clay barrier integrity assessment, and landfill stabilization monitoring. This could result in significant savings in time and money during characterization, remediation, and decommissioning of facilities.
Wright, David L.; Chew, Weng Cho
Upregulation of Rho-kinase (ROCK2) expression and enhanced contraction to endothelin-1 in the mesenteric artery from lipopolysaccharide-treated rats
Effects of bacterial lipopolysaccharide (Escherichia coli serotype, 055:B5, 20 mg kg?1, i.p., for 6 h) and a Rho-kinase inhibitor, (+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate, Y-27632 (10?9–10?5 M) were investigated on the contractile responses of the rat mesenteric artery to phenylephrine (10?9–3x10?5 M), angiotensin-2 (10?10–10?6 M) and endothelin-1 (10?10–10?7 M). Moreover, alteration in the level of Rho-kinase (ROCK-2) expression was examined in
Kansu Büyükaf?ar; Onur Ar?kan; Mustafa Ark; Havva Kubat; Elif Özveren
Enhancement of activated ? 1 -integrin expression by prostaglandin E 2 via EP receptors in isolated human coronary arterial endothelial cells: implication for the treatment of Kawasaki disease
.\\u000a Objective: Plasma prostaglandin E2 (PGE2) levels are markedly elevated in acute Kawasaki disease (KD). We evaluated the function of the EP receptors in the expression\\u000a of activated ?1-integrin stimulated by PGE2 in human coronary arterial endothelial cells (HCAEC).\\u000a \\u000a \\u000a \\u000a Methods: We determined the mRNA expression of the PGE2 receptors, EP receptors (EP1-4) in HCAEC by RT-PCR and protein expression by Western blotting.
M. Kajimoto; T. Ichiyama; Y. Ueno; M. Shiraishi; M. Hasegawa; S. Furukawa
Reocclusion of Recanalized Arteries during Intra-arterial Thrombolysis for Acute Ischemic Stroke
BACKGROUND AND PURPOSE: Early reocclusion of recanalized arteries has been observed after thrombolysis for acute coronary occlusion and has been attributed to platelet activation after exposure to thrombolytic agents. We conducted a retrospective study to determine the rate of reocclusion during intra-arterial thrombolysis for acute ischemic stroke and the effect of reocclusion on functional outcome. METHODS: Patients treated for acute
Adnan I. Qureshi; Amir M. Siddiqui; Stanley H. Kim; Ricardo A. Hanel; Andrew R. Xavier; Jawad F. Kirmani; M. Fareed; K. Suri; Alan S. Boulos; L. Nelson Hopkins
Effects of lactate/phosphate injection enhancement on oxidation stability and protein degradation in early postmortem beef cuts packaged in high oxygen modified atmosphere.
The influence of lactate/phosphate enhancement on meat color and lipid oxidation stability, tenderness, protein degradation, and protein aggregation of early postmortem beef muscles packaged in a high oxygen modified atmosphere packaging (HiOx-MAP; 80% O2, 20% CO2) were studied. At 24 hr postmortem, three bovine muscles (longissimus, semimembranosus, and adductor; n=10, respectively) were enhanced (10% injection rate) with either lactate (2.5%)/phosphate (0.3%) solution or water, packaged in HiOx-MAP, stored 9 days at 1°C, and then displayed for 7 days at 1°C. The lactate/phosphate injection significantly improved color stability (higher a* values) of all three bovine muscles throughout display period. Accumulation of lipid oxidation determined by 2-thiobarbituric acid-reactive substances values was also decreased (P<0.05) in the lactate/phosphate injection compared to the water treatment during storage and display periods. The objective tenderness values of longissimus and semimembranosus were also improved (P<0.05) by the lactate/phosphate enhancement treatment compared to the water treatment based on star probe measurement. There were no significant differences found in desmin and troponin-T degradation, or oxidative cross-linking of myosin between treatments. The results suggest that lactate/phosphate enhancement has beneficial effects on color and lipid oxidation stability, and tenderness development of beef cuts under HiOx-MAP conditions. PMID:20696536
Kim, Yuan H; Huff-Lonergan, Elisabeth; Sebranek, Joseph G; Lonergan, Steven M
\\u000a High blood pressure (BP) is a very important cardiovascular (CV) risk factor and is often labeled the "silent killer" because\\u000a arterial hypertension will lead to serious CV events such as ischemic heart disease, stroke, and heart failure. Moreover,\\u000a uncontrolled essential hypertension also leads to renal insufficiency, which accelerates the process of blood pressure elevation\\u000a (1, 2). There is a shift
Daniel A. Duprez
3D Geometry-Based Tracking and Segmentation of Carotid Arteries from CE-MR Angiograms Using Locally Adaptive Thresholdin
In this paper, a methodology, based on 3D geometry extracted from Contract-Enhanced MR Angiograms, is presented to identify and segment the internal carotid arteries for stenosis quantification. The internal carotid artery is automatically identified by tracking the carotid bifurcation and selecting the artery branch with no further arterial branches. To avoid the problems encountered using global thresholding, the artery segmentation
D. Stampouli; Martin R. Varley; C. F. Walshaw; A. P. Jones; R. W. Bury; Lik-kwan Shark
Enhanced discrimination of calcified and soft arterial plaques using computed tomography with a multi-energy-window photon counting x-ray detector
NASA Astrophysics Data System (ADS)
This work aims at discriminating between soft and calcified coronary artery plaques using microCT with a multi-energywindow photon counting X-ray detector (PCXD). We have previously investigated a solid state X-ray detector which has the capability to count individual photons in different energy windows. The data from these energy windows may be treated as multiple simultaneous X-ray acquisitions within non-overlapping energy windows that can provide additional information about tissue differences. In this work, we simulated a photon counting detector with five energy windows. We investigated two approaches for using the energy information provided by this detector. First, we applied energy weighting to the reconstruction from different energy windows to improve the signal-to-noise ratio between calcified and soft plaques. This resulted in a significant improvement in the signal-to-noise ratio. Second, we applied the basis material decomposition method to discriminate coronary artery plaques based on their calcium content. The results were compared with those obtained using dual-kVp material decomposition. We observed significantly improved contrast-tonoise ratios for the PCXD-based approaches.
Wang, Xiaolan; Xu, Jingyan; Taguchi, Katsuyuki; Patt, Bradley E.; Wagenaar, Douglas J.; Frey, Eric C.
Spontaneous isolated superior mesenteric artery dissection - Report of two cases.
Two cases of isolated superior mesenteric artery dissection diagnosed by contrast enhanced 64 slice CT are reported. In both, the dissection was seen extending along the entire length of the artery with one of them showing partially thrombosed false lumen. One case was associated with dissection of left renal artery with consequent renal infarcts. Although superior mesenteric artery dissection is a rare phenomenon, it should be considered in the differential diagnosis of abdominal angina. PMID:22470682
Srinivasan, Kaliappan Gurusamy; Srividya, Saravanan; Ushanandhini, Premnath; Ramprabananth, Sivanandan
Early fluid loading in acute respiratory distress syndrome with septic shock deteriorates lung aeration without impairing arterial oxygenation: a lung ultrasound observational study
Introduction The study was designed to assess the impact of fluid loading on lung aeration, oxygenation and hemodynamics in patients with septic shock and acute respiratory distress syndrome (ARDS). Methods During a 1-year period, a prospective observational study was performed in 32 patients with septic shock and ARDS. Cardiorespiratory parameters were measured using Swan Ganz (n?=?29) or PiCCO catheters (n?=?3). Lung aeration and regional pulmonary blood flows were measured using bedside transthoracic ultrasound. Measurements were performed before (T0), at the end of volume expansion (T1) and 40 minutes later (T2), consisting of 1-L of saline over 30 minutes during the first 48 h following onset of septic shock and ARDS. Results Lung ultrasound score increased by 23% at T2, from 13 at baseline to 16 (P?0.001). Cardiac index and cardiac filling pressures increased significantly at T1 (P?0.001) and returned to control values at T2. The increase in lung ultrasound score was statistically correlated with fluid loading-induced increase in cardiac index and was not associated with increase in pulmonary shunt or regional pulmonary blood flow. At T1, PaO2/FiO2 significantly increased (P?0.005) from 144 (123 to 198) to 165 (128 to 226) and returned to control values at T2, whereas lung ultrasound score continued to increase. Conclusions Early fluid loading transitorily improves hemodynamics and oxygenation and worsens lung aeration. Aeration changes can be detected at the bedside by transthoracic lung ultrasound, which may serve as a safeguard against excessive fluid loading.
Enhanced G2 chromatid radiosensitivity, an early stage in the neoplastic transformation of human epidermal keratinocytes in culture
A deficiency in DNA repair, manifest as enhanced chromatid radiosensitivity during the G2 phase of the cell cycle, together with a proliferative stimulus such as that provided by active oncogenes may be necessary and sufficient for the malignant neoplastic transformation of human keratinocytes in culture. Normal epidermal keratinocytes established as continuous cell lines by transfection with pSV3-neo or infection with adeno 12-SV40 hybrid virus developed enhanced G2 chromatid radiosensitivity after 18 passages in culture. In contrast to cells from primary or secondary culture, these cells could be transformed to malignant neoplastic cells by infection with Kirsten murine sarcoma virus containing the Ki-ras oncogene or in one line by the chemical carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine; both of these agents produced a marked proliferative response. Cytological heterogeneity and karyotypic instability characterized the cells during their progression to neoplasia. These results are interpreted in terms of a mechanism for neoplastic transformation.
Gantt, R.; Sanford, K.K.; Parshad, R.; Price, F.M.; Peterson, W.D. Jr.; Rhim, J.S.
Immunoglobulin M Capture Assay for Serologic Confirmation of Early Lyme Disease: Analysis of Immune Complexes with Biotinylated Borrelia burgdorferi Sonicate Enhanced with Flagellin Peptide Epitope
We previously reported on the efficacy of the enzyme-linked immunoglobulin M capture immune complex (IC) biotinylated antigen assay (EMIBA) for the seroconfirmation of early Lyme disease and active infection with Borrelia burgdorferi. In earlier work we identified non-cross-reacting epitopes of a number of B. burgdorferi proteins, including flagellin. We now report on an improvement in the performance of EMIBA with the addition of a biotinylated form of a synthetic non-cross-reacting immunodominant flagellin peptide to the biotinylated B. burgdorferi B31 sonicate antigen source with the avidin-biotinylated peroxidase complex detection system used in our recently developed indirect IgM-capture immune complex-based assay (EMIBA). As in our previous studies, the enzyme-linked immunosorbent assay (ELISA) reactivities of antibodies liberated from circulating ICs (by EMIBA) were compared with those of antibodies in unprocessed serum (antibodies found free in the serum, thus as an IgM-capture ELISA, but not EMIBA, because the antibodies were not liberated from ICs), the sample usually used in standard ELISAs and Western blot assays. The addition of the flagellin epitope enhanced the ELISA signal obtained with untreated sera from many Lyme disease patients but not from healthy controls. In tests with both free antibodies and ICs, with or without the addition of the flagellin epitope to the sonicate, we found the most advantageous combination was IC as the source of antibodies and sonicate plus the flagellin epitope as the antigen. In a blinded study of sera obtained from patients with early and later-phase Lyme disease, EMIBA with the enhanced antigenic preparation compared favorably with other serologic assays, especially for the confirmation of early disease.
Brunner, Michael; Stein, Stanley; Mitchell, Paul D.; Sigal, Leonard H.
An enhanced bunionectomy model as a potential tool for early decision-making in the development of new analgesics
Background Bunionectomy has been used as a model of postoperative pain for opioids and nonsteroidal anti-inflammatory drugs\\/cyclooxygenase-2\\u000a inhibitors with a fast onset of analgesia. The present study was conducted to assess whether the utility of the model can\\u000a be broadened in assessing the efficacy of analgesics with diverse mechanisms and pharmacokinetic profiles in drug development\\u000a and to enhance the sensitivity of
Hao Wang; Cynthia Gargano; Suzanne Lukac; Alice Jackson; Chan Beals; Patricia Smiley; Melissa Drexel; Marcella Ruddy; Gary Herman; Amy O. Johnson-Levonas; Robert Medve; Lynn Webster; Alise Reicin
A functional analysis of the genes Enhancer of split and HLH-m5 during early neurogenesis in Drosophila melanogaster
To assess the functional domains of the proteins encoded by E(spl) and HLH-m5, two genes of the Enhancer of split complex [E(SPL)-C] of Drosophila melanogaster, a number of variants have been made by in vitro mutagenesis, transformed into the germ line of the wild-type, and genetically combined with a chromosomal deletion lacking four of the genes of the E(SPL)-C. All
Kyria Tietze; Herbert Schrons; José A. Campos-Ortega; Elisabeth Knust
Endovascular Treatment of a Coronary Artery Bypass Graft to Pulmonary Artery Fistula with Coil Embolization
Fistula formation between a coronary artery bypass graft (CABG)and the pulmonary arterial circulation represents a rare cause of recurrent angina in patients following bypass grafting. Therapy has traditionally involved surgical ligation by open thoracotomy. We describe a case of left internal mammary artery-left upper lobe pulmonary artery fistula presenting as early recurrent angina following CABG. The fistula was embolized using platinum coils, resulting in symptomatic relief and improvement in myocardial perfusion on cardiac perfusion scintigraphy. Coil embolization should be considered a therapeutic option in patients with coronary-pulmonary steal syndrome.
Nielson, Jeffery L., E-mail: email@example.com; Kang, Preet S. [University Hospitals of Cleveland and Veterans Administration Medical Center-Cleveland, Case Western Reserve University, Departments of Radiology (United States)
In Vivo Replication of Recombinant Murine Cytomegalovirus Driven by the Paralogous Major Immediate-Early Promoter-Enhancer of Human Cytomegalovirus
Transcription of the major immediate-early (MIE) genes of cytomegaloviruses (CMV) is driven by a strong promoter-enhancer (MIEPE) complex. Transactivator proteins encoded by these MIE genes are essential for productive infection. Accordingly, the MIEPE is a crucial control point, and its regulation by activators and repressors is pertinent to virus replication. Since the MIEPE contains multiple regulatory elements, it was reasonable to assume that specific sequence motifs are irreplaceable for specifying the cell-type tropism and replication pattern. Recent work on murine CMV infectivity (A. Angulo, M. Messerle, U. H. Koszinowski, and P. Ghazal, J. Virol. 72:8502–8509, 1998) has documented the proposed enhancing function of the enhancer in that its resection or its replacement by a nonregulatory stuffer sequence resulted in a significant reduction of infectivity, even though replication competence was maintained by a basal activity of the spared authentic MIE promoter. Notably, full capacity for productive in vitro infection of fibroblasts was restored in recombinant viruses by the human CMV enhancer. Using two-color in situ hybridization with MIEPE-specific polynucleotide probes, we demonstrated that a murine CMV recombinant in which the complete murine CMV MIEPE is replaced by the paralogous human CMV core promoter and enhancer (recombinant virus mCMVhMIEPE) retained the potential to replicate in vivo in all tissues relevant to CMV disease. Notably, mCMVhMIEPE was also found to replicate in the liver, a site at which transgenic hCMV MIEPE is silenced. We conclude that productive in vivo infection with murine CMV does not strictly depend on a MIEPE type-specific regulation.
Grzimek, Natascha K. A.; Podlech, Jurgen; Steffens, Hans-Peter; Holtappels, Rafaela; Schmalz, Susanne; Reddehase, Matthias J.
An alternative estimation of the RF-enhanced plasma temperature during SPEAR artificial heating experiments: Early results
NASA Astrophysics Data System (ADS)
RF heating of the F region plasma at high latitudes has long been known to produce electron temperature increases that can vary from tens to hundreds of percent above the background, unperturbed level. In contrast, artificial ionospheric modification experiments conducted using the Space Plasma Exploration by Active Radar (SPEAR) heating facility on Svalbard have often failed to produce obvious enhancements in the electron temperatures when measured using the European Incoherent Scatter Svalbard radar (ESR), colocated with the heater. Contamination of the ESR ion line spectra by the zero-frequency purely growing mode (PGM) feature is known to persist at varying amplitudes throughout SPEAR heating, and such spectral features can lead to significant temperature underestimations when the incoherent scatter spectra are analyzed using conventional methods. In this study, we present the first results of applying a recently developed technique to correct the PGM-contaminated spectra to SPEAR-enhanced ESR spectra and derive an alternative estimate of the SPEAR-heated electron temperature. We discuss how the effectiveness of the spectrum corrections can be affected by the data variance, estimated over the integration period. The subsequent electron temperatures, inferred from corrected spectra, range from a few tens to a few hundred Kelvin above the average background temperature. These temperatures are found to be in reasonable agreement with the theoretical "enhanced" temperature, calculated for the peak of the stationary temperature perturbation profile, when realistic absorption effects are accounted for.
Vickers, H.; Baddeley, L.
Coronary artery disease (image)
... through these arteries is critical for the heart. Coronary artery disease usually results from the build-up of fatty material and plaque, a condition called atherosclerosis. As the coronary arteries narrow, the flow of blood to the ...
Coronary artery fistula (image)
A coronary artery fistula generally occurs when one of the coronary arteries fails to form properly during the development of the baby. Coronary artery fistula is an abnormal connection between one of ...
Trial participants' experiences of early enhanced speech and language therapy after stroke compared with employed visitor support: a qualitative study nested within a randomized controlled trial
Objectives: To explore trial participants' experiences of the process and outcomes of early, enhanced speech and language therapy after stroke with support from an employed visitor. Design: Qualitative study nested within a randomized controlled trial. Participants: Twney-two people who, after stroke, had a diagnosis of aphasia (12), dysarthria (5) or both (5) and who participated in the ACT NoW study. Setting: Eight English NHS usual care settings. Method: Individual interviews. Thematic content analysis assisted by a bespoke data transformation protocol for incorporating non-verbal and semantically ambiguous data. Results: Participants highly regarded regular and sustained contact with someone outside of immediate family/friends who engaged them in deliberate activities/communication in the early months after stroke. Participants identified differences in the process of intervention between speech and language therapists and employed visitors. But no major discriminations were made between the impact or value of this contact according to whether provided by a speech and language therapist or employed visitor. Participant-defined criteria for effectiveness of contact included: impact on mood and confidence, self-recognition of progress and the meeting of individual needs. Conclusions: As in the randomized controlled trial, participants reported no evidence of added benefit of early communication therapy beyond that from attention control. The findings do not imply that regular contact with any non-professional can have beneficial effects for someone with aphasia or dysarthria in the early weeks following a stroke. The study points to specific conditions that would have to be met for contact to have a positive effect.
Gomersall, Timothy; Bowen, Audrey
Early drotrecogin alpha (activated) administration in severe sepsis is associated with lower mortality: a retrospective analysis of the Canadian ENHANCE cohort
Introduction Early multimodal treatment of severe sepsis, including the use of drotrecogin alfa (activated) (DrotAA) when indicated, is considered essential for optimum outcome. However, predicting which infected patients will progress to severe sepsis and the need for aggressive intervention continues to be problematic. We therefore wished to explore whether there were any potential early markers that might predict improved survival in response to early use of DrotAA in patients with severe sepsis. In particular, in the dynamic setting of severe sepsis, we postulated that changes in markers reflecting evolving rather than baseline clinical status might guide therapy. Methods Data on a cohort of 305 Canadian patients from the open label ENHANCE trial of DrotAA in severe sepsis was retrospectively analyzed to search for potential clinical predictors of outcome in severe sepsis. Patients received a 96-hour infusion of DrotAA and were followed for 28 days. The association between time to treatment and mortality within subgroups defined by dynamic changes in various potential markers was explored. Results Mortality at 28 days was 22.6% and the variables of age, time to treatment, and early changes in serum creatinine and platelet count were identified by logistic regression as independent predictors of mortality. Across all age ranges, 28-day mortality was lower when DrotAA was administered within 24 hours of first sepsis-induced organ dysfunction compared to administration after 24 hours for both subgroups of patients defined by changes in platelet count and creatinine within the first day. Conclusions These findings suggest that when indicated, treatment with DrotAA should be initiated as soon as possible, regardless of age. Trial Registration Previous trial registration number: NCT00568893
Hodder, Richard V; Hall, Richard; Russell, James A; Fisher, Harold N; Lee, Bobbie
In Vivo Gene Transfer of Nitric Oxide Synthase Enhances Vasomotor Function in Carotid Arteries From Normal and Cholesterol-Fed Rabbits
Background—The vascular endothelium is anatomically intact but functionally abnormal in preatherosclerotic states, and an early deficit in the bioavailability of nitric oxide (NO) or related molecules has been described in both humans and animal models. We hypothesized that the targeted gene transfer of NO synthase (NOS) isoforms might ameliorate or reverse the deficit. Methods and Results—We constructed a recombinant adenovirus,
Keith M. Channon; HuSheng Qian; Valentina Neplioueva; Michael A. Blazing; Ercument Olmez; Geetha A. Shetty; Scot A. Youngblood; John Pawloski; Timothy McMahon; Jonathan S. Stamler; Samuel E. George
Embryos of Robertsonian Translocation Carriers Exhibit a Mitotic Interchromosomal Effect That Enhances Genetic Instability during Early Development
Balanced chromosomal rearrangements represent one of the most common forms of genetic abnormality affecting approximately 1 in every 500 (0.2%) individuals. Difficulties processing the abnormal chromosomes during meiosis lead to an elevated risk of chromosomally abnormal gametes, resulting in high rates of miscarriage and/or children with congenital abnormalities. It has also been suggested that the presence of chromosome rearrangements may also cause an increase in aneuploidy affecting structurally normal chromosomes, due to disruption of chromosome alignment on the spindle or disturbance of other factors related to meiotic chromosome segregation. The existence of such a phenomenon (an inter-chromosomal effect—ICE) remains controversial, with different studies presenting contradictory data. The current investigation aimed to demonstrate conclusively whether an ICE truly exists. For this purpose a comprehensive chromosome screening technique, optimized for analysis of minute amounts of tissue, was applied to a unique collection of samples consisting of 283 oocytes and early embryos derived from 44 patients carrying chromosome rearrangements. A further 5,078 oocytes and embryos, derived from chromosomally normal individuals of identical age, provided a robust control group for comparative analysis. A highly significant (P?=?0.0002) increase in the rate of malsegregation affecting structurally normal chromosomes was observed in association with Robertsonian translocations. Surprisingly, the ICE was clearly detected in early embryos from female carriers, but not in oocytes, indicating the possibility of mitotic rather than the previously suggested meiotic origin. These findings have implications for our understanding of genetic stability during preimplantation development and are of clinical relevance for patients carrying a Robertsonian translocation. The results are also pertinent to other situations when cellular mechanisms for maintaining genetic fidelity are relaxed and chromosome rearrangements are present (e.g. in tumors displaying chromosomal instability).
Alfarawati, Samer; Fragouli, Elpida; Colls, Pere; Wells, Dagan
In vivo evaluation of retinal and callosal projections in early postnatal development and plasticity using manganese-enhanced MRI and diffusion tensor imaging.
The rodents are an excellent model for understanding the development and plasticity of the visual system. In this study, we explored the feasibility of Mn-enhanced MRI (MEMRI) and diffusion tensor imaging (DTI) at 7 T for in vivo and longitudinal assessments of the retinal and callosal pathways in normal neonatal rodent brains and after early postnatal visual impairments. Along the retinal pathways, unilateral intravitreal Mn2+ injection resulted in Mn2+ uptake and transport in normal neonatal visual brains at postnatal days (P) 1, 5 and 10 with faster Mn2+ clearance than the adult brains at P60. The reorganization of retinocollicular projections was also detected by significant Mn2+ enhancement by 2%-10% in the ipsilateral superior colliculus (SC) of normal neonatal rats, normal adult mice and adult rats after neonatal monocular enucleation (ME) but not in normal adult rats or adult rats after monocular deprivation (MD). DTI showed a significantly higher fractional anisotropy (FA) by 21% in the optic nerve projected from the remaining eye of ME rats compared to normal rats at 6 weeks old, likely as a result of the retention of axons from the ipsilaterally uncrossed retinal ganglion cells, whereas the anterior and posterior retinal pathways projected from the enucleated or deprived eyes possessed lower FA after neonatal binocular enucleation (BE), ME and MD by 22%-56%, 18%-46% and 11%-15% respectively compared to normal rats, indicative of neurodegeneration or immaturity of white matter tracts. Along the visual callosal pathways, intracortical Mn2+ injection to the visual cortex of BE rats enhanced a larger projection volume by about 74% in the V1/V2 transition zone of the contralateral hemisphere compared to normal rats, without apparent DTI parametric changes in the splenium of corpus callosum. This suggested an adaptive change in interhemispheric connections and spatial specificity in the visual cortex upon early blindness. The results of this study may help determine the mechanisms of axonal uptake and transport, microstructural reorganization and functional activities in the living visual brains during development, diseases, plasticity and early interventions in a global and longitudinal setting. PMID:21985904
Chan, Kevin C; Cheng, Joe S; Fan, Shujuan; Zhou, Iris Y; Yang, Jian; Wu, Ed X
The history of chemical enrichment and the sites of early nucleosynthesis: CNO abundances of galactic carbon-enhanced metal-poor stars
NASA Astrophysics Data System (ADS)
This dissertation focuses on abundance analyses of carbon-enhanced metal-poor (CEMP) Galactic halo stars. Different methods for determining carbon, nitrogen, oxygen, and also some barium abundances are described. The study of these abundances in such stars serves to investigate the means by which the Universe became enriched in metals. Due to the different kinds of CEMP stars observed in the Milky Way, it can only be assumed that there is certainly more than one method of carbon-enhancement at early times. Complete abundance analyses for as many of these archaeological relics as possible are needed in order to constrain the astrophysical sites of early carbon production. There are three main parts of this dissertation. The first part describes new techniques to determine oxygen abundances from spectra of the near-infrared molecular CO bands. With the near-IR OSIRIS spectrograph on the SOAR 4.1-m telescope, 57 CEMP stars were observed. A wide range of oxygen abundances were estimated, and the results were statistically compared to high-resolution estimates for both carbon-enhanced and carbon-normal metal-poor stars. Abundance patterns of the sample stars were compared to yield predictions for very metal-poor asymptotic giant branch (AGB) stars. The majority of the sample exhibit patterns consistent with CEMP stars having s-process-element enhancements, and thus have very likely been polluted by carbon- and oxygen-enhanced material transferred from a metal-poor AGB companion. The second part delineates a new survey effort implemented in order to identify new CEMP stars. For the initial pilot study, a new selection technique was developed based solely on the strength of the CH G band at 4300 A. This technique eliminated previous temperature and metallicity biases present in other CEMP surveys. Observations of the pilot sample were carried out with the Goodman HTS spectrograph on the SOAR 4.1-m telescope. Of the over 120 candidate stars observed, over 35% were found to be CEMP stars. The selection technique was then improved to include a second index for the strength of the G band, and the survey was continued on both the SOAR and Gemini telescopes. After this extension, the success rate of this program increased to 50%. The final part of this dissertation contains details of a pilot study of known metal-poor stars using the X-Shooter spectrograph on the Very Large Telescope (VLT). With three spectrograph arms (near-ultraviolet, optical, and near-infrared), this instrument was used to calculate carbon, nitrogen, oxygen, and barium abundances for a sample of 27 CEMP stars. The broad spectral range of this instrument is unprecedented, and it is an efficient way to estimate abundances for several pertinent species in just one exposure per star. Of the 27 stars, many proved to be enhanced in carbon. The majority appear to be consistent with s-process-element enhancement, but there was one extremely metal-poor star which falls into the rare family of CEMP stars with no neutron-capture-element enhancement.
Kennedy, Catherine R.
A rare cause of upper gastrointestinal haemorrhage: Ruptured cystic artery pseudoaneurysm with concurrent cholecystojejunal fistula.
INTRODUCTION Cystic artery pseudoaneurysms and cholecystoenteric fistulae represent two rare complications of gallstone disease. PRESENTATION OF CASE An 86 year old male presented to the emergency department with obstructive jaundice, RUQ pain and subsequent upper gastrointestinal bleeding. Upper GI endoscopy revealed bleeding from the medial wall of the second part of the duodenum and a contrast-enhanced computed tomography scan revealed a cystic artery pseudoaneurysm, concurrent cholecystojejunal fistula and gallstone ileus. This patient was successfully managed surgically with open subtotal cholecystectomy, pseudoaneurysm resection and fistula repair. DISCUSSION To date there are very few cases describing haemobilia resulting from a bleeding cystic artery pseudoaneurysm. This report is the first to describe upper gastrointestinal bleeding as a consequence of two synchronous rare pathologies: a ruptured cystic artery pseudoaneurysm causing haemobilia and bleeding through a concurrent cholecystojejunal fistula. CONCLUSION Through this case, we stress the importance of accurate and early diagnosis through ultra- sonography, endoscopy, and contrast-enhanced CT imaging and emphasise that haemobilia should be included in the differential diagnosis of anyone presenting with upper gastrointestinal bleeding. We have demonstrated the success of surgical management alone in the treatment of such a case, but accept that consideration of combined therapeutic approach with angiography be given in the first instance, when available and clinically indicated. PMID:24394852
Glaysher, Michael A; Cruttenden-Wood, David; Szentpali, Karoly
[Intra-arterial fibrinolytic therapy for acute mesenteric ischemia].
We report a case of mesenteric ischemia secondary to embolic occlusion treated by percutaneous intra-arterial thrombolysis. Early initial radiographic evaluation included abdominal plain film, ultrasonography, abdominal CT, and arteriography. Only selective superior mesenteric artery angiography provided definite diagnosis. The duration of ischemic symptoms before thrombolysis was 6 hours. Post procedure angiogram at 12 hours showed complete resolution of the mesenteric arterial thrombus with clinical improvement. The most important criteria for patient survival is early diagnosis and immediate treatment. Direct infusion of urokinase into the superior mesentric artery may be an alternative to surgery in selected patients and particularly in patients without evidence of frank bowel necrosis. PMID:11223630
Michel, C; Laffy, P; Leblanc, G; Riou, J Y; Chaloum, S; Maklouf, M; Le Guen, O; Pitre, J
Mitochondrial reactive oxygen species enhance AMP-activated protein kinase activation in the endothelium of patients with coronary artery disease and diabetes.
The aim of the present study was to determine whether the endothelial dysfunction associated with CAD (coronary artery disease) and T2D (Type 2 diabetes mellitus) is concomitant with elevated mtROS (mitochondrial reactive oxygen species) production in the endothelium and establish if this, in turn, regulates the activity of endothelial AMPK (AMP-activated protein kinase). We investigated endothelial function, mtROS production and AMPK activation in saphenous veins from patients with advanced CAD. Endothelium-dependent vasodilation was impaired in patients with CAD and T2D relative to those with CAD alone. Levels of mitochondrial H(2)O(2) and activity of AMPK were significantly elevated in primary HSVECs (human saphenous vein endothelial cells) from patients with CAD and T2D compared with those from patients with CAD alone. Incubation with the mitochondria-targeted antioxidant, MitoQ(10) significantly reduced AMPK activity in HSVECs from patients with CAD and T2D but not in cells from patients with CAD alone. Elevated mtROS production in the endothelium of patients with CAD and T2D increases AMPK activation, supporting a role for the kinase in defence against oxidative stress. Further investigation is required to determine whether pharmacological activators of AMPK will prove beneficial in the attenuation of endothelial dysfunction in patients with CAD and T2D. PMID:23057846
Mackenzie, Ruth M; Salt, Ian P; Miller, William H; Logan, Angela; Ibrahim, Hagar A; Degasperi, Andrea; Dymott, Jane A; Hamilton, Carlene A; Murphy, Michael P; Delles, Christian; Dominiczak, Anna F
Mitochondrial reactive oxygen species enhance AMP-activated protein kinase activation in the endothelium of patients with coronary artery disease and diabetes
The aim of the present study was to determine whether the endothelial dysfunction associated with CAD (coronary artery disease) and T2D (Type 2 diabetes mellitus) is concomitant with elevated mtROS (mitochondrial reactive oxygen species) production in the endothelium and establish if this, in turn, regulates the activity of endothelial AMPK (AMP-activated protein kinase). We investigated endothelial function, mtROS production and AMPK activation in saphenous veins from patients with advanced CAD. Endothelium-dependent vasodilation was impaired in patients with CAD and T2D relative to those with CAD alone. Levels of mitochondrial H2O2 and activity of AMPK were significantly elevated in primary HSVECs (human saphenous vein endothelial cells) from patients with CAD and T2D compared with those from patients with CAD alone. Incubation with the mitochondria-targeted antioxidant, MitoQ10 significantly reduced AMPK activity in HSVECs fr