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Cho Young I YI Department of Mechanical Eng. and Mechanics, Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA, - - 2014
This review examines the emerging role of endothelial shear stress (ESS) and blood viscosity on the initiation and progression of atherosclerosis in peripheral arterial disease. Among the variables determining ESS, blood viscosity has to date been the most overlooked by clinical researchers. Blood viscosity is a laboratory assessment that is ...
Dandekar Vineet K - - 2014
Despite increasing clinical use, there is limited data regarding regadenoson in stress perfusion cardiovascular magnetic resonance (CMR). In particular, given its long half-life the optimal stress protocol remains unclear. Although Myocardial Perfusion Reserve (MPR) may provide additive prognostic information, current techniques for its measurement are cumbersome and challenging for routine ...
Yan Z Z University of Wisconsin-Madison, Madison, Wisconsin 53706, - - 2014
Comprehensive 2D turbulence and eddy flow velocity measurements on DIII-D demonstrate a rapidly increasing turbulence-driven shear flow that develops ∼100  μs prior to the low-confinement (L mode) to high-confinement (H mode) transition and appears to trigger it. These changes are localized to a narrow layer 1-2 cm inside the magnetic boundary. Increasing ...
Ghose Somdeb S The Institute of Mathematical Sciences, CIT Campus, Chennai 600113, - - 2014
Recent experiments imaging fluid flow around swimming microorganisms have revealed complex time-dependent velocity fields that differ qualitatively from the stresslet flow commonly employed in theoretical descriptions of active matter. Here we obtain the most general flow around a finite sized active particle by expanding the surface stress in irreducible Cartesian ...
Yen Jen-Hong JH Department of Water Resources and Environmental Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, New Taipei, 251, Taiwan, - - 2014
Non-physiologic turbulent flow occurs in medical cardiovascular devices resulting in hemodynamic stresses that may damage red blood cells (RBC) and cause hemolysis. Hemolysis was previously thought to result from Reynolds shear stress (RSS) in turbulent flows. A more recent hypothesis suggests that turbulent viscous shear stresses (TVSS) at spatial scales ...
Evans David J DJ Department of Thoracic Medicine, Hemel Hempstead Hospital, Hemel Hempstead, - - 2014
Previous studies have highlighted flow shear stress as a possible damage mechanism for small airways, in particular those liable to constriction through disease or injury due to mechanical ventilation. Flow experiments in vitro have implicated shear stress as a relevant factor for mechanotransduction pathways with respect to airway epithelial cell ...
Blagojević Milan - - 2014
Practical difficulties, particularly long model development time, have limited the types and applicability of computational fluid dynamics simulations in numerical modeling of blood flow in serial manner. In these simulations, the most revealing flow parameters are the endothelial shear stress distribution and oscillatory shear index. The aim of this study ...
Moh Jeong-Hah JH Division of Mechanical and Automotive Engineering, Wonkwang University, Jeollabuk-do, South - - 2014
The present research investigated the role of blood viscosity on flow within a microvascular network to identify the conditions of blood flow stagnation. When the yield stress of blood was less than 0.005 Pa, there were no stagnant regions in the microvasculature. However, when the yield stress increased to 0.05 ...
Teległów Aneta A Department of Clinical Rehabilitation, University School of Physical Education, Cracow, - - 2014
The aim of this study was to analyze the changes in blood rheology resulting from regular winter swimming. The study was carried out on 12 male winter swimmers. Venous blood for morphological, biochemical and rheological analysis was sampled twice from each winter swimmer - at the beginning of the season ...
Watanabe-Asaka Tomomi - - 2014
The development of blood flow in the heart is crucial for heart function and embryonic survival. Recent studies have revealed the importance of the extracellular matrix and the mechanical stress applied to the valve cushion that controls blood flow to the formation of the cardiac valve during embryogenesis. However, the ...
Kynkäänniemi Sanna-Mari SM Department of Biology, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland, - - 2014
Blood-sucking ectoparasites have often a strong impact on the behaviour of their hosts. The annual insect harassment of reindeer (Rangifer tarandus tarandus) has increased in the southern part of the Finnish reindeer herding area because of the recent invasion of a blood-feeding ectoparasitic louse-fly, the deer ked (Lipoptena cervi). We ...
de Zambotti Massimiliano M Center for Health Sciences, SRI International, Menlo Park, CA, USA; Department of General Psychology, University of Padua, Padua, - - 2014
Narcolepsy with cataplexy is a complex sleep disorder that affects the modulation of emotions: cataplexy, the key symptom of narcolepsy, is indeed strongly linked with emotions that usually trigger the episodes. Our study aimed to investigate haemodynamic and behavioural responses during emotional stimulation in narco-cataplexy. Twelve adult drug-naive narcoleptic patients ...
- - 2014
Background: Experimental data suggest stress-related cognitive dysfunction may be associated with increased blood-brain-barrier (BBB) permeability secondary to immune activation. Methods: We investigated the relationship between prolonged and intense physical and psychological combat-training stress, immune activation and blood-brain-barrier permeability in 37 healthy male army medical rapid response troops. Results: Soldiers during ...
Freund Jonathan B JB Mechanical Science & Engineering and Aerospace Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801. Electronic address: - - 2014
It is well known that mechanotransduction of hemodynamic forces mediates cellular processes, particularly those that lead to vascular development and maintenance. Both the strength and space-time character of these forces have been shown to affect remodeling and morphogenesis. However, the role of blood cells in the process remains unclear. We ...
Mostafa T T Department of Andrology and Sexology, Faculty of Medicine, Cairo University, Cairo, - - 2014
This study aimed to assess glutathione-S-transferase (GST) enzyme- oxidative stress (OS) relationship in the internal spermatic vein (ISV) of infertile men associated with varicocele (Vx). Ninety five infertile oligoasthenoteratozoospemic (OAT) men associated with Vx were subjected to history taking, clinical examination and semen analysis. During inguinal varicocelectomy, GST, malondialdehyde (MDA) ...
Hoseinabadi Sedigheh S a Department of Occupational Health , Shahrood University of Medical Sciences , Shahrood , - - 2014
Abstract This study has been carried out to investigate the effect of traffic load on the level of blood adrenaline hormone and its influences on the distance estimation and recognition accuracy among urban bus drivers. The level of blood adrenaline hormone has been regarded as stress index. 69 urban bus ...
Zhang Xiaoyan X From the Department of Biomedical Engineering, University of Kentucky, Lexington (X.Z., R.C., D.R., G.Y., H.Y.S); Math, Science, and Technology Center, Paul L. Dunbar High School, Lexington, KY (D.R.); Division of Cardiovascular Disease, University of Alabama at Birmingham (P.S.); and Saha Cardiovascular Research Center, University of Kentucky, Lexington - - 2014
Shear stress-induced pseudopod retraction is an anti-inflammatory measure that minimizes neutrophil activity and is regulated by membrane cholesterol. We tested the hypothesis that a hypercholesterolemic impairment of shear mechanotransduction alters the neutrophil flow behavior leading to microvascular dysfunction. We examined the shear effects on the flow behavior of human leukocytes. ...
Georgakarakos Efstratios E 1 Department of Vascular Surgery, Democritus Medical School, University Hospital of Alexandroupolis, Alexandroupolis - - - 2014
Purpose: To evaluate the flow phenomena within an aortic endograft with crossed-limbs, comparing to an endograft with the ordinary limb bifurcation.Methods: An endograft model with crossed-limbs was computationally reconstructed based on Computed Tomography patient-specific data, using commercially available software. Accordingly, its analogue model was reconstructed in the ordinary fashion (ordinary ...
Wortel Geert H GH Kamerlingh Onnes Lab, Universiteit Leiden, Postbus 9504, 2300 RA Leiden, The - - 2014
We probe the rheology of weakly vibrated granular flows as function of flow rate, vibration strength, and pressure by performing experiments in a vertically vibrated split-bottom shear cell. For slow flows, we establish the existence of a vibration-dominated granular flow regime, where the driving stresses smoothly vanish as the driving ...
Galay Remil Linggatong RL Department of Pathological and Preventive Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida, Yamaguchi, Japan; Laboratory of Emerging Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Korimoto, Kagoshima, - - 2014
Ticks are obligate hematophagous parasites that have successfully developed counteractive means against their hosts' immune and hemostatic mechanisms, but their ability to cope with potentially toxic molecules in the blood remains unclear. Iron is important in various physiological processes but can be toxic to living cells when in excess. We ...
- - 2014
[This corrects the article DOI: 10.1371/journal.pone.0081073.].
Jodko Daniel D Łódź University of Technology, Institute of Turbomachinery, Łódź, - - 2014
The Ciminio-Brescia arterio-venous fistula is a preferred vascular access for haemodialysis, but it is often associated with the development of vascular complications, due to changes in hemodynamic conditions. Computational fluid dynamics methods were involved to carry out seven simulations of the blood flow through the fistula for the patient specific ...
Vitiello Damien D Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger Street East, Montreal, QC, Canada H1T 1C8 ; Departments of Medicine and Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, QC, - - 2014
Background. Changes in cardiopulmonary reserve and biomarkers related to wall stress, inflammation, and oxidative stress concomitantly with the evaluation of peripheral arterial blood flow have not been investigated in patients with heart failure with preserved ejection fraction (HFpEF) compared with healthy subjects (CTL). Methods and Results. Eighteen HFpEF patients and ...
Srivastava Neetu N Department of Mathematics, Amrita Vishwa Vidyapeetham (University), Karnataka 560 035, - - 2014
Analytical investigation of MHD blood flow in a porous inclined stenotic artery under the influence of the inclined magnetic field has been done. Blood is considered as an electrically conducting Newtonian fluid. The physics of the problem is described by the usual MHD equations along with appropriate boundary conditions. The ...
Ikemura Tsukasa - - 2013
Heat stress induces various physiological changes and so could influence ocular circulation. This study examined the effect of heat stress on ocular blood flow. Ocular blood flow, end-tidal carbon dioxide (PETCO2) and blood pressure were measured for 12 healthy subjects wearing water-perfused tube-lined suits under two conditions of water circulation: ...
Smith Marissa N - - 2013
To fully understand the potentially harmful effects of prenatal stress exposure impacts, it is necessary to quantify long-term and episodic stress exposure during pregnancy. There is a strong body of research relating psychological stress to elevated cortisol levels in biomarkers. Recently, maternal hair has been used to measure cortisol levels, ...
Bouzid Mehdi M Physique et Mécanique des Milieux Hétérogènes, PMMH UMR 7636 ESPCI-CNRS, Université Paris-Diderot, Université Pierre et Marie Curie, 10 rue Vauquelin, 75005 Paris, - - 2013
The rheology of dense granular flows is studied numerically in a shear cell controlled at constant pressure and shear stress, confined between two granular shear flows. We show that a liquid state can be achieved even far below the yield stress, whose flow can be described with the same rheology ...
Mazzaro Lisa M - - 2013
Handling, including blood collection, has often been discouraged in molting penguins because it is considered an additional stress imposed on birds already experiencing major physiologic stress associated with molting. To evaluate the degree of physiologic stress posed by molting, we compared the hematologic and plasma biochemical values and hormone levels ...
Hope Katrina - - 2013
Non-freezing cold injury (NFCI) is a prevalent, but largely undiagnosed and poorly understood syndrome afflicting many who, as part of their work or leisure, expose their extremities to cold temperatures. The long term sequelae of NFCI are hyperhidrosis, cold-sensitivity and pain; these can last a lifetime. We tested the hypothesis ...
Peng Henry T - - 2013
Thromboelastography (TEG) is drawing more attention for clinical and laboratory studies of hemostasis. It has been applied to evaluate the effects of both psychological and physiological stress on whole blood coagulation from the onset of the coagulation cascade through clot formation, to the end with fibrinolysis. We conducted a comprehensive ...
Henning H H Unit for Reproductive Medicine of Clinics, University of Veterinary Medicine Hannover, Hannover, Germany; Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Hannover, - - 2014
The objective was to assess the effect of a short-term scrotal hyperthermia in dogs on quantitative and qualitative ejaculate parameters, testicular blood flow and testicular and epididymal histology. After a control period, the scrotum of seven normospermic adult beagle dogs was insulated with a self-made suspensory for 48 h. Nine weeks ...
Schubert Gerrit Alexander GA From the Department of Neurosurgery, Uniklinik RWTH Aachen, Aachen, Germany (G.A.S.); Department of Neurosurgery, Universitätsmedizin Mannheim, University of Heidelberg, Heidelberg, Germany (G.A.S., M.S.); Department of Neurosurgery, Charité Universitätsmedizin Berlin, Berlin, Germany (M.C., P.V.); Department of Neurosurgery, Dr. Horst Schmidt Klinik (HSK), Wiesbaden, Germany (P.H.); and Department of Neurosurgery, Medical University Innsbruck, Innsbruck, Austria - - 2014
Moyamoya disease (MMD) is characterized by unique angiographic features of collateralization. However, a detailed quantification as well as comparative analysis with cerebrovascular atherosclerotic disease (CAD) and healthy controls have not been performed to date. We reviewed 67 patients with MMD undergoing Xenon-enhanced computed tomography, as well as 108 patients with ...
Alshare Aiman - - 2013
Steady flow simulations of blood flow in an axisymmetric stenosed artery, subjected to a static magnetic field, are performed to investigate the influence of artery size, magnetic field strength, and non-Newtonian behavior on artery wall shear stress and pressure drop in the stenosed section. It is found that wall shear ...
Jomen Wataru - - 2013
A 62-year-old man with transfusion-dependent severe aplastic anemia received immunosuppressive therapy (IST) with rabbit antithymocyte globulin and cyclosporine A in April 2010. However, his transfusion dependency did not improve. As more than 100 red blood cell (RBC) transfusions had been performed, he was administered iron chelation therapy (ICT) with deferasirox ...
Balankin Alexander S AS Grupo "Mecánica Fractal," ESIME-Zacatenco, Instituto Politécnico Nacional, México Distrito Federal 07738, - - 2013
The aim of this Reply is to elucidate the difference between the fractal continuum models used in the preceding Comment and the models of fractal continuum flow which were put forward in our previous articles [Phys. Rev. E 85, 025302(R) (2012); 85, 056314 (2012)]. In this way, some drawbacks of ...
Tarasev Michael M Blaze Medical Devices, Ann Arbor, - - 2014
Red blood cell (RBC) storage lesions have been suggested as contributing factors to suboptimal clinical outcomes. While undesirable effects of storage are well documented, their clinical relevance is still debated. Focus on storage time as the sole determinant of RBC quality ignores the variability in cell properties that may depend ...
Wu Zhongjun - - 2013
The goal of this study is to develop a computational fluid dynamics (CFD) modeling approach to better estimate the blood flow dynamics in the bundles of the hollow fiber membrane based medical devices (i.e. blood oxygenators, artificial lungs and hemodialyzers). Three representative types of arrays, square, diagonal and random, with ...
Chaudhuri Pinaki - - 2013
A confined colloidal glass, under the imposition of a uniform shear stress, is investigated using numerical simulations. Both at macro- and microscales, the consequent dynamics during the onset of flow is studied. When the imposed stress is gradually decreased, the time scale for the onset of steady flow diverges, associated ...
Cueno Marni E - - 2013
Butyric acid (BA) induces jugular blood mitochondrial oxidative stress, whereas heme-induced oxidative stress was previously reported to inhibit SIRT1 in vitro. This would imply that BA-induced oxidative stress may similarly affect SIRT1. Here, we elucidated the BA effects on jugular blood cytosolic oxidative stress and SIRT1. Jugular blood cytosol was ...
Yin Wei - - 2013
The goal of this study was to establish a computational fluid dynamics model to investigate the effect of cyclic motion (i.e., bending and stretching) on coronary blood flow. The three dimensional geometry of a 50-mm section of the left anterior descending artery (normal or with a 60% stenosis) was constructed ...
Marassá Ana Maria - - 2013
Introduction The aim of this study was to identify the blood feeding sources of Nyssomyia intermedia (Ny. intermedia) and Nyssomyia neivai (Ny. neivai), which are Leishmania vectors and the predominant sandfly species in the Ribeira Valley, State of São Paulo, Brazil, an endemic area for cutaneous leishmaniasis. Methods Specimens were ...
Peiffer Véronique - - 2013
Spatial variation of the haemodynamic stresses acting on the arterial wall is commonly assumed to explain the focal development of atherosclerosis. Disturbed flow in particular is thought to play a key role. However, widely-used metrics developed to quantify its extent are unable to distinguish between uniaxial and multidirectional flows. We ...
Walker Andrew M - - 2013
Particle image velocimetry (PIV) was used to investigate the influence of a non-Newtonian blood analog of aqueous xanthan gum on flow separation in laminar and transitional environments and in both steady and pulsatile flow. Initial steady pressure drop measurements in laminar and transitional flow for a Newtonian analog showed an ...
Yang Ruoting - - 2013
Post-traumatic stress disorder (PTSD) is a severe anxiety disorder that affects a substantial portion of combat veterans and poses serious consequences to long-term health. Consequently, the identification of diagnostic and prognostic blood biomarkers for PTSD is of great interest. Previously, we assessed genome-wide gene expression of seven brain regions and ...
Nakamura Masanori - - 2013
We examined the deformation behavior of a red blood cell (RBC) in various flow fields to determine whether the extent of RBC deformation is correlated with the shear stress used as a hemolysis index. The RBC model was introduced to a simple shear flow (Couette flow) and to slightly complex ...
Ogoh Shigehiko - - 2013
The purpose of the present study was to assess the effect of heat stress-induced changes in systemic circulation on intra- and extracranial blood flows and its distribution. Twelve healthy subjects with a mean age of 22±2 (s.d.) years dressed in a tube-lined suit and rested in a supine position. Cardiac ...
Bellieni Cv - - 2013
Abstract Aim: To assess whether blood values of C-reactive protein (CRP) in healthy term newborns, are influenced by stress. Material and methods: Since different types of delivery [vaginal delivery (VD), emergency C-section (EMCS) and elective C- section (ELCS)] are notoriously characterized by different levels of stress for the baby, these ...
Sadler Annelisa M - - 2013
Repeated blood sampling from laboratory animals is desirable in certain experimental designs and also for reducing the number of animals used in research. Biochemical methods for analysing blood samples require only small blood volumes to be collected (typically 20-40 µL). In juvenile mice, the small blood volume of the animals also ...
Li Jingan - - 2013
The morphology of vascular smooth muscle cells (SMCs) in the normal physiological state depends on cytoskeletal distribution and topology beneath, and presents vertical to the direction of blood flow shear stress (FFSS) although SMCs physiologically are not directly exposed to the shear conditions of blood flow. However, this condition is ...
Tashtoush Bourhan - - 2013
Steady flow simulations of blood flow in an axisymmetric stenosed artery, in the presence of a static magnetic field, were performed to investigate the influence of artery size; magnetic field strength, non-Newtonian viscosity and stenosis severity on artery wall shear stress and pressure drop in the stenosed section. It is ...
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