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Lucats Laurence - - 2008
AIMS: Postsystolic wall thickening (PSWT) occurs after aortic valve closure. We investigated the influence of ischemia location and wall interactions on PSWT in normal and stunned myocardium. METHODS AND RESULTS: Twenty-two dogs were studied. Seven chronically instrumented dogs (sonomicrometry) underwent 10-min coronary artery occlusion (CAO) of left circumflex artery ("LCX ...
Chytilová E - - 2009
Arterial sites with low wall shear stress (WSS) are more prone to the development of atherosclerotic plaques, as was observed in carotid arteries in subjects with atherosclerosis risk factors. Type 2 diabetes mellitus (DM), hypertension, hyperlipidemia and other components of the metabolic syndrome, are associated with high risk for symptomatic ...
Ferrara A - - 2008
We present 3D finite element models of atherosclerotic arteries, used to investigate the influence of the geometry and tissue properties on the plaque rupture caused by overexpansion. We adopted a geometry reconstructed from a contiguous set of in vitro magnetic resonance images of a damaged artery. The artery wall is ...
Antonova Mariya L - - 2008
The arterial wall viscoelasticity plays an essential role in the vascular responsiveness to vasoactive drugs or pathologies. The aim of this investigation was to derive and compare resonance curve (RC), natural frequency (f(0)), dynamic modulus of elasticity (E'), and coefficient of viscosity (beta) of (i) vital and devitalized preparations of ...
Blake James R - - 2008
A simple technique to estimate the wall shear rate in healthy arteries using a clinical ultrasound scanner has been developed. This method uses the theory of fully developed oscillatory flow together with a spectral Doppler trace and an estimate of mean arterial diameter. A method using color flow imaging was ...
Sibon Igor - - 2008
OBJECT: Amine oxidases play a key role in the polymerization and cross-linking of the collagens and elastic lamellae of the arterial wall. The loss of elastic lamellae integrity is one of the first steps in the genesis of a cerebral aneurysm. The authors investigated the relation between semicarbazide-sensitive amine oxidase ...
Wilkens J L - - 2008
Lobster arteries, which exhibit non-uniform elasticity when stretched, have a trilaminar organization. The inner layer is an elastic connective tissue and the outer layer is a collagenous connective tissue; the middle layer of an artery is an aggregation of cells containing microfilaments. Arterial cells possess actin, myosin and tropomyosin. Except ...
Yamashita A - - 2008
Expansive vascular remodeling is considered a feature of vulnerable plaques. Although inflammation is upregulated in the media and adventitia of atherosclerotic lesions, its contribution to expansive remodeling is unclear. We investigated this issue in injured femoral arteries of normo- and hyperlipidemic rabbits fed with a conventional (CD group; n=20) or ...
Pezet Mylène - - 2008
Elastin, the main component of elastic fibers, is synthesized only in early life and provides the blood vessels with their elastic properties. With aging, elastin is progressively degraded, leading to arterial enlargement, stiffening, and dysfunction. Also, elastin is a key regulator of vascular smooth muscle cell proliferation and migration during ...
Black P N - - 2008
Small airways are the major site of airflow obstruction in chronic obstructive pulmonary disease (COPD). This is attributed to loss of elastin in alveoli and fibrosis in small airways. In the present study, it was hypothesised that changes to elastic fibres in alveoli might be paralleled by a similar reduction ...
Fonck, Edouard
The intent of this thesis is to study the function of elastin in cerebral arteries, its contribution into the aging process and its implication into different cerebral diseases and in particular cerebral aneurysms. As of today, little is known on the genesis, growth and rupture of cerebral aneurysm. It is ...
Gong Bin - - 2008
BACKGROUND: Using a recent model of dissecting aortic aneurysm (DAA) caused by in utero exposure to semicarbazide, we examined the elastin and collagen using standard methods and two nonlinear imaging techniques, multiphoton fluorescence (MPF) and second harmonic generation (SHG) microscopy. METHODS: Sprague-Dawley rat dams were given semicarbazide (6.13 mg/kg/day i.p.) ...
Cernes Relu - - 2008
Arterial stiffness is an independent risk factor for premature cardiovascular morbidity and mortality that can be evaluated by noninvasive methods and can be reduced by good clinical management. The present chapter examines the association between arterial stiffness and cardiovascular risk factors including hypertension, metabolic syndrome, diabetes, advanced renal failure, hypercholesterolemia ...
Tuka Vladimir - - 2008
BACKGROUND/AIMS: The feeding artery of dialysis vascular access is subjected to unusually high wall shear stress (WSS), a hemodynamic factor leading to vasodilatation, for at least several months after access creation. Physiologically, high WSS leads to compensatory endothelium-dependent vasodilatation. We supposed that the dilatation of the feeding artery continues to ...
Woodman Richard J - - 2008
Increased arterial stiffness is influenced by both functional and structural properties of the vessel wall, including changes in content of smooth muscle, elastin and collagen, reduced endothelial production of NO and increased release of endothelin-1 or AngII (angiotensin II). The RAS (renin-angiotensin) system is likely to be central to increases ...
Miyamoto Shimpei - - 2008
To perform safe anastomosis for atherosclerotic arteries, we employed a posterior-wall-first anastomotic technique with a short-thread double-needle microsuture. Between October 2005 and September 2007, we performed 17 free flap transfers to the head and neck regions with this technique. Fifteen of 17 patients had one or more risk factors for ...
Plekhanova O S - - 2008
Perivascular application of urokinase to the ballooned artery promoted the growth of neointima and constrictive remodeling of the vessel and stimulated the inflammatory response in the damaged vascular wall in vivo. Recombinant tissue plasminogen activator did not induce these changes. Our results indicate that urokinase is involved in the regulation ...
Wang Yuh-Ying Lin YY The Department of Physics, National Taiwan Normal University, Taipei, Taiwan. - - 2008
Many rehabilitation exercises involve the stretching of bodies. We point out the necessity of the longitudinal stretching in arteries. The efficiency of an arterial system is closely related to the condition of the transverse vibration of the arterial walls or to the magnitudes of the area oscillation in all blood ...
Azeloglu Evren U EU Department of Biomedical Engineering, Columbia University, New York, NY 10027, - - 2008
The arterial wall contains a significant amount of charged proteoglycans, which are inhomogeneously distributed, with the greatest concentrations in the intimal and medial layers. The hypothesis of this study is that the transmural distribution of proteoglycans plays a significant role in regulating residual stresses in the arterial wall. This hypothesis ...
Olgac Ufuk - - 2008
The work herein represents a novel approach for the modeling of low-density lipoprotein (LDL) transport from the artery lumen into the arterial wall, taking into account the effects of local wall shear stress (WSS) on the endothelial cell layer and its pathways of volume and solute flux. We have simulated ...
Laughlin M Harold MH Department of Biomedical Sciences, College of Veterinary Medicine, 1600 E. Rollins Rd., University of Missouri, Columbia, MO 65211, USA. - - 2008
Current evidence indicates that the ability of physical activity to sustain a normal phenotype of arterial endothelial cells (ECs) plays a central role in the beneficial effects of exercise (Ex) on atherosclerotic disease. Here we evaluate the strength of evidence that shear stress (SS) and/or circumferential wall stress (stretch) are ...
Abisi Said - - 2007
Cysteine proteases are potent elastolytic enzymes and together with their inhibitor, cystatin C, have been linked with the growth of abdominal aortic aneurysms (AAAs). These enzymes and their inhibitors have previously been studied in AAAs, but comparisons have always been made with wall from normal aorta. Atherosclerosis is a feature ...
Kerwin William - - 2008
The purpose of this study was to investigate whether large arteries in subjects with Ehlers-Danlos Syndrome Type IV (EDS IV) exhibit altered morphological and functional characteristics that might indicate the risk of complications. Subjects with EDS IV, an inherited disorder of type III collagen, have a significant lifetime risk of ...
Dasouki Majed - - 2007
Mutations involving elastic tissue proteins result in a broad spectrum of phenotypes affecting skin, skeleton, ocular and vascular structures, including tortuous blood vessels and cutis laxa. Here we report on a female newborn with apparently long fingers, aortic aneurysm, tortuous pulmonary arteries and mild generalized lax skin. She died at ...
Claridge Martin W - - 2008
The aim of the study was to investigate the reproducibility of estimation of Young's modulus E and pressure strain elastic modulus Ep, derived from a tissue Doppler imaging (TDI) wall motion technique. Healthy subjects had their arteries insonated at the same sitting by two different observers and at two different ...
Bia Daniel - - 2007
The aim of this study was to characterize and compare human great saphenous veins (HGSVs), HGSV cryoallografts, expanded polytetrafluoroethylene (ePTFE) segments, and elastic and muscular arteries' biomechanics, so as to identify if the biomechanical coupling and the HGSV advantages with respect to ePTFE depend on the arterial type and/or on ...
Wikstrand John - - 2007
BACKGROUND: With an increasing number of randomized studies investigating the anti-atherosclerotic effects of different preventive measures utilizing ultrasound evaluation of intima-media thickness of the carotid artery as the primary endpoint, it is of interest to critically evaluate the validity of these measurements. METHODS AND RESULTS: Small structures, the dimensions of ...
Arko Frank R - - 2007
It is commonly assumed that the aortic wall deforms uniformly and has uniform wall thickness about the circumference. The purpose of this study was to evaluate the aortic wall motion and thickness in the infrarenal aortic neck of patients with abdominal aortic aneurysms who were undergoing endovascular repair (EVAR) and ...
Thrush Abigail J - - 2008
The aim of this in vitro study is to assess the accuracy of the tissue Doppler imaging arterial wall motion (TDI AWM) technique in measuring dilation over a range of distances and velocities. A test rig, consisting of two parallel blocks of tissue mimicking material (TMM), has been developed to ...
Dietrich C F - - 2007
The intestinal wall can be visualized using high resolution transabdominal ultrasound. The normal intestinal wall thickness in the terminal ileum, cecum, and right and left colon is <2mm when examined with graded compression. It is important to appreciate that a contracted intestinal segment can be misinterpreted as a thickened wall. ...
Guo Zi-Yi - - 2008
BACKGROUND: Internal elastic lamella and elastic lamellae serve as barriers for macromolecular accumulation in vascular wall. The function of internal elastic lamella in atherogenesis induced by shear stress has not been well understood yet. In the present study, internal elastic lamella remodeling and transmural accumulation of macromolecules in the arterial ...
Nguyen Kien T - - 2008
It has been widely observed that atherosclerotic diseases occur at sites with complex hemodynamics, such as artery bifurcations, junctions, and regions of high curvature. These regions usually have very low or highly oscillatory wall shear stress (WSS). In the present work, 3D pulsatile blood flow through a model of the ...
Harris L K - - 2007
BACKGROUND: During pregnancy, extravillous trophoblast invades the uterine wall and enters the spiral arteries. Remodelling ensues, with loss of vascular smooth muscle cells (SMCs) to create high flow, low resistance vessels. Pregnancies complicated by pre-eclampsia are characterized by incomplete arterial remodelling. Endovascular trophoblast is not easily accessible for studies to ...
Kadirvel Ramanathan - - 2007
INTRODUCTION: Biological and biophysical factors have been shown to play an important role in the initiation, progression, and rupture of intracranial aneurysms. The purpose of this study was to evaluate the association between hemodynamic forces and markers of vascular remodeling in elastase-induced saccular aneurysms in rabbits. METHODS: Elastase-induced aneurysms were ...
Wang Jie-Mei - - 2007
BACKGROUND: Impaired artery elasticity has been found in various pathological conditions related to endothelial dysfunction. Recently, CD31+/CD42- microparticles (MPs) emerged as a marker of endothelial injury. Whether CD31+/CD42- MPs, generated under physiological conditions, are correlated with artery properties has not been reported. METHODS: We evaluated brachia-ankle pulse-wave velocity (baPWV) (n ...
Lakatta Edward G - - 2007
The structure and function of central arteries change throughout the lifetime of humans and animals. Since atherosclerosis and hypertension are prevalent in epidemic proportion among older persons, it is reasonable to hypothesize that specific mechanisms that underlie the arterial substrate that has been altered by an "aging process" are intimately ...
Challa Vinay - - 2007
OBJECTIVE: Saccular aneurysm (sac-like ballooning) is the common form of aneurysm in cerebral arteries. Significant variations exist in the shape, wall thickness and material properties of saccular aneurysms. Aneurysms with irregular shapes are prone to rupture, but the underlying reason is poorly understood. The objective of this study was to ...
Kielty Cay M CM Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK. - - 2007
For the treatment of vascular disease, the major cause of death in Western society, there is an urgent need for tissue-engineered, biocompatible, small calibre artery substitutes that restore biological function. Vascular tissue engineering of such grafts involves the development of compliant synthetic or biomaterial scaffolds that incorporate vascular cells and ...
Maerefat Mehdi - - 2007
In the present study, the estimation of elastic modulus of large arteries is used as an index for arterial stiffness. At first, a dynamic model is introduced for pulsatile blood flow in arteries with elastic walls. The model is based on Navier-Stokes equations in fluid mechanics and the theory of ...
Hamilton Paul K - - 2007
Most traditional cardiovascular risk factors alter the structure and/or function of arteries. An assessment of arterial wall integrity could therefore allow accurate prediction of cardiovascular risk in individuals. The term 'arterial stiffness' denotes alterations in the mechanical properties of arteries, and much effort has focused on how best to measure ...
Folkesson Maggie - - 2007
It has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA enlargement and rupture. The growth of the AAA is dependent on proteolytic degradation of elastin. Here, we analysed whether the neutrophil gelatinase-associated lipocalin (NGAL) is expressed within the thrombus and the aneurysm wall. NGAL ...
Goergen Craig J - - 2007
To determine whether variations in aortic wall motion exist in mammalian species other than humans and to consider the potential implications of such variations. M-mode ultrasound was used to measure abdominal aortic wall motion in 4 animal species [mice (n=10), rats (n=8), rabbits (n=7), and pigs (n=5)], and humans (n=6). ...
Haas Tara L - - 2007
Persistent elevation in shear stress within conduit or resistance arteries causes structural luminal expansion, which serves to normalize shear stress while maintaining increased flow to the downstream vasculature. Although it is known that this adaptation involves cellular proliferation and remodeling of the extracellular matrix, the specific cellular events underlying these ...
Alastrué Victor - - 2007
Numerical and analytical studies on cylindrical geometries have shown the relevance of accounting for residual stresses in arterial modeling. However, multiple difficulties, both geometrical and numerical, arise when enforcing residual stresses in patient-specific arteries. This is the reason of the few simulations that have been developed on this kind of ...
Gogly Bruno - - 2007
OBJECTIVE: Embryo-like gingival healing properties are attributed to the gingival fibroblast (GF) and could be used as a model for other types of healing dysfunctions. Abdominal aortic aneurysm (AAA) formation is associated with elastin degradation and increase in matrix metalloproteinase (MMP)-9 activity. We aimed to validate the concept of using ...
Chung Ada W Y - - 2007
Thoracic aortic aneurysm (TAA) is the life-threatening complication of Marfan syndrome (MFS), a connective tissue disorder caused by mutations in the fibrillin-1 gene. TAA is characterized by degradation of elastic fiber, suggesting the involvement of matrix metalloproteinase (MMP)-2 and -9, the activation of which is regulated by TIMP (tissue inhibitor ...
Ozgur Zuhal - - 2007
The differences in the course and shape of the internal carotid artery (ICA) in the parapharyngeal space were investigated to determine the possible risks for serious hemorrhage during tonsillectomy, drainage of peritonsillar abscess, soft palate injuries, adenoidectomy and velopharyngeoplasty. The course of the ICA was studied in the parapharyngeal spaces ...
Megens Remco T A - - 2007
We evaluated CNA35 as a collagen marker in healthy and atherosclerotic arteries of mice after both ex vivo and in vivo administration and as a molecular imaging agent for the detection of atherosclerosis. CNA35 conjugated with fluorescent Oregon Green 488 (CNA35/OG488) was administered ex vivo to mounted viable muscular (uterine), ...
Hayward C S - - 2007
1. With the ageing population and increasing heart failure, arterial function has been shown to contribute to cardiovascular risk because of its adverse effects on ventriculovascular coupling. Population studies have confirmed independent prognostic information of arterial stiffening on cardiovascular survival. 2. The term 'arterial function' encompasses a range of phenotypes, ...
Ritman Erik L EL Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55905, USA. - - 2007
The function of vasa vasorum is both to deliver nutrients and oxygen to arterial and venous walls and to remove "waste" products, either produced by cells in the wall or introduced by diffusional transport through the endothelium of the artery or vein. Although the relationship between changes in vasa vasorum ...
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