Search Results
Results 301 - 350 of 1723
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Klein Andrew J - - 2009
BACKGROUND: The unique physical forces exerted on the femoropopliteal (FP) artery during movement have been implicated in the high rates of restenosis and stent fracture in this artery. Conformational changes in the FP artery during movement are important surrogates of these forces. This study sought to quantify the conformational change ...
Park Ji Kang - - 2009
In this study, we evaluated the wall of saccular cerebral aneurysms (SCAs) using two-dimensional double inversion recovery black-blood sequence (BBDI). We examined 14 patients with an unruptured SCA (USCA). The BBDI was peripheral-pulse gated, and was acquired during the mid-diastolic period. We evaluated whether the aneurysmal wall could be visualized ...
Cohn Jay N - - 2009
Noninvasive evaluation of the health of the vasculature is an increasingly important approach to identifying individuals at risk for cardiovascular morbid events. Vascular health assessment involves functional and structural examination of the large and small arteries. Endothelial dysfunction, which alters small artery function, is a key contributor to progressive structural ...
Matthews Peter B - - 2009
BACKGROUND AND AIM OF THE STUDY: Pulmonary autograft dilation can lead to aortic insufficiency requiring reoperation. Remodeling occurs when the pulmonary root is subjected to systemic pressure. It is unknown whether a regional variability of the material properties exists within the root, resulting in unequally distributed wall stress prior to ...
Yazici Ilker - - 2009
In this article, we present the use of triangulation for end-to-side microvascular arterial anastomosis. The classic end-to-side anastomosis starts by putting 2 sutures 180 degrees apart to the lateral arteriotomy aperture that is parallel to the longitudinal axis. We are performing triangulation in end-to-side microvascular artery anastomoses by putting 3 ...
Wang Chong C Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, 22908, - - 2009
The stress distribution in the vessel wall has an important bearing on vascular function in health and disease. We studied the relationship between the transmural stress distribution and the opening angle (OA) to determine the stress gradient. The simulation of wall stress was based on transmural measurements of strain and ...
Chen Henry Y HY Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, - - 2010
Vascular cross-clamping is applied in many cardiovascular surgeries such as coronary bypass, aorta repair and valve procedures. Experimental studies have found that clamping of various degrees caused damage to arteries. This study examines the effects of popular clamps on vessel wall. Models of the aorta and clamp were created in ...
Massey Philip G PG University of Washington, Seattle, WA 98195-7710, - - 2009
Urokinase-type plasminogen activator (uPA) is expressed at increased levels in stenotic, atherosclerotic human arteries. However, the biological roles of uPA in the artery wall are poorly understood. Previous studies associate uPA with both acute vasoconstriction and chronic vascular remodeling and attribute uPA-mediated vasoconstriction to the kringle - not the catalytic ...
Kawasaki Toshihiro - - 2009
OBJECTIVE: The elastic properties of the carotid arterial wall have not been directly characterized in the clinical setting. Strain rate (SR) imaging is a newly developed echocardiographic method developed for imaging the tissue motion of the myocardium. The purpose of this study was to directly estimate the elastic properties of ...
Bjarnegård Niclas - - 2010
The normal aging process of the brachial artery (BA) wall is of specific interest since it is often selected as a model artery in studies of vascular function. With echo-tracking ultrasound, diameter, absolute diameter change, and intima-media thickness (IMT) were registered in 60 healthy subjects, 21-86 yr (30 men), at ...
Karmonik C - - 2010
PURPOSE: The quantification of wall motion in cerebral aneurysms is of interest for the assessment of aneurysmal rupture risk, for providing boundary conditions for computational simulations and as a validation tool for theoretical models. MATERIALS AND METHODS: 2D cine phase contrast magnetic resonance imaging (2D pcMRI) in combination with quantitative ...
Horiguchi Masahito - - 2009
Great arteries, as well as lungs and skin, contain elastic fibers as important components to maintain their physiological functions. Although recent studies have revealed that a glycoprotein fibulin-4 (FBLN4) is indispensable for the assembly of mature elastic fibers, it remains to be elucidated how FBLN4 takes part in elastogenesis. Here, ...
Carta Luca L Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, NY 10029, - - 2009
Even though elastin and fibrillin-1 are the major structural components of elastic fibers, mutations in elastin and fibrillin-1 lead to narrowing of large arteries in supravalvular aortic stenosis and dilation of the ascending aorta in Marfan syndrome, respectively. A genetic approach was therefore used here to distinguish the differential contributions ...
Wang Susanna S SS Department of Human Genetics, UCLA David Geffen School of Medicine, Los Angeles, CA, - - 2009
Disruption of the elastic lamina, as an early indicator of aneurysm formation, and vascular calcification frequently occur together in atherosclerotic lesions of humans. We now report evidence of shared genetic basis for disruption of the elastic lamina (medial disruption) and medial calcification in an F(2) mouse intercross between C57BL/6J and ...
Zhao Yilin - - 2010
Alternatives to using native arteries in vascular surgery are urgently needed. Vessels made from synthetic polymers have shortcomings such as thrombosis, rejection, intimal hyperplasia, calcification, infection, chronic inflammation and no growth potential. Tissue-engineered blood vessels (TEBV) may overcome these problems. We developed a tissue-engineered artery using autologous bone marrow derived ...
Thacher Tyler - - 2009
Cyclic circumferential stretch and shear stress act in concert and yet are capable of independently mediating arterial smooth muscle function, modulating the production of superoxide and stimulating arterial remodeling. Porcine carotid arteries were perfused ex vivo for 72 h. Groups combining normal (5%) and reduced (1%) stretch with high shear ...
Gonzalez Magdalena - - 2009
Vascular calcification is caused by the deposition of basic calcium phosphate crystals in blood vessels, myocardium, and/or cardiac valves. Calcification decreases artery wall compliance, and arterial calcification is associated to mortality in hyperphosphatemic renal failure and diabetes mellitus. The calcification of the tunica media characterizes the arteriosclerosis observed with age, ...
Rachev Alexander - - 2009
Organ culture systems are used to study remodeling of arteries and to fabricate tissue engineered vascular grafts. Investigations to date focused on changes in geometry and mechanical response of arteries or constructs associated with controlled sustained alterations in the global load parameters such as the arterial pressure, flow, or axial ...
Collette Mathieu - - 2009
PURPOSE: Stiffness of the large arteries (e.g., aorta) plays an important role in the pathogenesis of cardiovascular diseases. To date, the reference method for the determination of regional arterial stiffness is the measurement of the carotid-femoral pulse wave velocity (PWV) by tonometric techniques. However, this method suffers from several drawbacks ...
Eriksson Thomas - - 2009
A model for saccular cerebral aneurysm growth, proposed by Kroon and Holzapfel (2007, "A Model for Saccular Cerebral Aneurysm Growth in a Human Middle Cerebral Artery," J. Theor. Biol., 247, pp. 775-787; 2008, "Modeling of Saccular Aneurysm Growth in a Human Middle Cerebral Artery," ASME J. Biomech. Eng., 130, p. ...
Masugata Hisashi - - 2009
Large vessel vasculitis leads to arterial wall thickening and stiffening because of chronic inflammatory changes. The cardio-ankle vascular index (CAVI) is recently utilized for assessing arterial stiffening caused by atherosclerosis-related diseases, including hypertension and diabetes, as well as aging. CAVI is mathematically calculated from stiffness index beta, which is established ...
Watton Paul N - - 2009
The physiological mechanisms that give rise to the inception and development of a cerebral aneurysm are accepted to involve the interplay between the local mechanical forces acting on the arterial wall and the biological processes occurring at the cellular level. In fact, the wall shear stresses (WSSs) that act on ...
Trachet Bram - - 2009
In this paper, the influence of the aortic dimensions of an investigated mouse on its resulting wall shear stress (WSS) was studied. A numerical model of a mouse aortic arch was created based on a micro-CT scan of a vascular corrosion cast of an 8-week-old wild type mouse. This model ...
Van Epps J Scott JS Department of Surgery, McGowan Institute for Regenerative Medicine, Center for Vascular Remodeling and Regeneration, University of Pittsburgh, PA 15219, - - 2009
Certain arteries (e.g., coronary, femoral, etc.) are exposed to cyclic flexure due to their tethering to surrounding tissue beds. It is believed that such stimuli result in a spatially variable biomechanical stress distribution, which has been implicated as a key modulator of remodeling associated with atherosclerotic lesion localization. In this ...
Chuang Ting-Hsien TH Department of Bioengineering, Clemson University, Clemson, South Carolina 29634, - - 2009
Tissue-engineered vascular grafts require elastic, acellular porous scaffolds with controlled biodegradability and properties matching those of natural arteries. Elastin would be a desirable component for such applications, but elastin does not easily regenerate experimentally. Our approach is to develop tubular elastin scaffolds using decellularization and removal of collagen from porcine ...
Ke Xue Dan - - 2010
Pathological levels of homocysteine induce a dramatic degradation of arterial elastic structures. This severe metalloproteinase-dependant elastolysis affects elastic structures all over the media suggesting that smooth muscle cells (SMC) may participate to this process induced by homocysteine. Therefore, we investigated the effect of physiological (10 microM) and pathological (50, 100, ...
Myredal Anna - - 2010
Ultrabiomicroscopy is a novel high-frequency (55 MHz) ultrasound technique that could be used to non-invasively measure the vessel wall and separate the intima-media complex into measurements of intima and media thickness. Since no previous study has measured intima and media thickness separately in vivo in patients with coronary heart disease ...
Valentín A A Department of Biomedical Engineering, 337 Zachry Engineering Center, 3120 TAMU, Texas A&M University, College Station, TX 77843-3120, - - 2009
Evolving constituent composition and organization are important determinants of the biomechanical behaviour of soft tissues. In arteries, vascular smooth muscle cells and fibroblasts continually produce and degrade matrix constituents in preferred modes and at altered rates in response to changing mechanical stimuli. Smooth muscle cells similarly exhibit vasoactive changes that ...
Jeffcoate W J - - 2009
Calcification of the media of arterial walls is common in diabetes and is particularly associated with distal symmetrical neuropathy. Arterial calcification also complicates chronic kidney disease and is an independent risk factor for cardiovascular and all-cause mortality. The term calcification is not strictly accurate because the morphological changes incorporate those ...
Miller Steven J - - 2010
Aging is a major risk factor for the development of cardiovascular diseases, including arterial occlusive disease. Oxidant stress increases with age, and may be a significant factor contributing to vascular dysfunction and disease. We have shown that aging and hypertension impair collateral growth, the natural compensatory response to arterial occlusive ...
Jones Jeffrey A - - 2009
The present study tested the hypothesis that changes in the resident endogenous cellular population accompany alterations in aortic collagen and elastin content during thoracic aortic aneurysm (TAA) development in a murine model. Descending thoracic aortas were analyzed at various time points (2, 4, 8, and 16 weeks) post-TAA induction (0.5 ...
Resch Markus - - 2009
Splanchnic vasodilation is the pathophysiological hallmark in the development of the hyperdynamic circulatory syndrome in liver cirrhosis and portal hypertension. This has been attributed so far mainly to a marked vascular hyporeactivity to endogenous vasoconstrictors. However, myogenic tone and vessel stiffness have not been addressed in mesenteric arteries in liver ...
Ohki Shin-ichi - - 2009
A 59-year-old man was transferred to our hospital because of mural thrombus in the ascending aorta. He had suffered some neurological dysfunctions such as transient dysorientation. Electrocardiogram showed normal sinus rhythm without premature beats. Trans-thoracic echocardiogram and three-dimensional CT showed a mobile mural mass sticking to the ascending aortic wall. ...
Krasinski Adam - - 2009
This study was designed to evaluate 3-D ultrasound (3DUS)-derived vessel wall volume (VWV), a 3-D measurement of the carotid artery intima and media, including atherosclerotic plaque, in patients enrolled in a randomized placebo-controlled three-month study of intensive atorvastatin treatment. Thirty-five subjects with carotid stenosis >60% who provided written informed consent ...
Roy S - - 2009
Vascular smooth muscle is a major structural element of the arterial wall. We examined the effects of cytoskeleton destruction, after administration of Cytochalasin D, on the biomechanical properties of porcine common carotids. Compared to untreated, maximally dilated controls, Cytochalasin D-treated arteries have shown a marked increase in compliance in the ...
Badran Hala Mahfouz - - 2009
BACKGROUND: Differential diagnosis between ischemic (IDCM) and the nonischemic type (NIDCM) of cardiomyopathy constitutes a challenge in the daily medical practice. Carotid and aortic elastic properties deteriorate in patients with coronary artery disease. However, their predictive role in differentiating IDCM from NIDCM has not been addressed so far. AIM OF ...
Kang Kyusik - - 2009
OBJECTIVES: Structural changes in the extracranial carotid artery are associated with an increase in left ventricular (LV) mass and relative wall thickness. The present study was performed to determine the relation of LV mass index and relative wall thickness to suspected atherosclerotic steno-occlusive disease of the intracranial arteries on magnetic ...
Liao Dan D Molecular Surgeon Research Center, Division of Vascular Surgery and Endovascular Therapy, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, and Michael E. DeBakey VA Medical Center, Houston, TX 77030, - - 2009
Establishing thrombosis-resistant surface is crucial to develop tissue-engineered small diameter vascular grafts for arterial reconstructive procedures. The objective of this study was to evaluate the stability and anti-coagulation properties of heparin covalently linked to decellularized porcine carotid arteries. Cellular components of porcine carotid arteries were completely removed with chemical and ...
Mohler Emile R ER 3rd Department of Medicine, Cardiovascular Division, Section of Vascular Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. - - 2009
The measurement of carotid intima-medial thickness is a well-validated measure of cardiovascular risk. Although atherosclerosis occurs in the intima, this arterial layer is not measured alone because of the limitation in ultrasound resolution with standard-frequency probes. We evaluated the feasibility of using a 55-MHz ultrasound system with high resolution to ...
Stapleton C H - - 2009
The presence of axillary artery aneurysm and/or thrombus in overhead throwing athletes has been linked, theoretically, with the finding of compression by the humeral head induced by a diagnostic arm maneuver. However, whether this intermittent compression is incidental or of pathological significance has yet to be determined. Flow-mediated vasodilation (FMD), ...
Dorfmann A - - 2010
In this paper, we develop a physiologic wall stress analysis procedure by incorporating experimentally measured, non-uniform pressure loading in a patient-based finite element simulation. First, the distribution of wall pressure is measured in a patient-based lumen cast at a series of physiologically relevant steady flow rates. Then, using published equi-biaxial ...
Sorice Gian Pio - - 2009
The aetiology of aortic aneurysms (AAs) is the subject of intense clinical investigation. One of the critical points in their pathogenesis is the disruption of the balance between vascular extracellular matrix deposition and degradation. AAs are common features in some genetically determined diseases of the connective tissue, such as Marfan ...
Kornaat Peter R - - 2009
PURPOSE: The purpose of the study was to determine if a positive association exists between arterial vessel wall thickness and generalized osteoarthritis (OA). Our hypothesis is that generalized OA is another facet of the metabolic syndrome. MATERIALS AND METHODS: The medical ethical review board of our institution approved the study. ...
Hashimoto Junichiro - - 2009
Aging has a striking impact on the arterial structure and function. The principal structural change with age is medial degeneration that leads to a progressive stiffening of the large elastic arteries. Large artery stiffening increases aortic systolic and pulse pressures through an increase in the forward incident wave and an ...
Matlung Hanke L - - 2009
Shear stress is well known to be a key factor in the regulation of small-artery tone and structure. Although nitric oxide is a major endothelium-derived factor involved in short- and long-term regulation of vascular caliber, it is clear that other mechanisms also can be involved. This review discusses the evidence ...
Pearce Gillian - - 2009
We present data concerning the extraction of clots using the newly invented "GP" mechanical thrombectomy device (MTD). Artificial and porcine clots of various lengths were used in plastic tube models of an artery. We investigate the pressures and times taken for clot extraction together with the volumes of fluid extracted. ...
Bia Daniel - - 2009
While the situation of tissue donation and transplantation differs between Latin American and European countries, a common problem is tissue deficiency. Hence, at present, there is a pressing need to generate alternatives so as to increase the possibilities of obtaining the requested materials. Consequently, it would be of significant interest ...
McAdams R M - - 2009
Umbilical artery catheter (UAC) use is common in the management of critically ill neonates; however, little information exists regarding the anatomic and vascular effects of UAC placement in premature newborns. Baboons were delivered at 125 days of gestation (term=185 days), treated with surfactant, had UACs placed and were ventilated for ...
Russell Nicola S - - 2009
BACKGROUND AND PURPOSE: Vascular disease is increased after radiotherapy and is an important determinant of late treatment-induced morbidity and excess mortality. This study evaluates the nature of underlying pathologic changes occurring in medium-sized muscular arteries following irradiation. MATERIALS AND METHODS: Biopsies of irradiated medium-sized arteries and unirradiated control arteries were ...
Huo Yunlong - - 2009
A hemodynamic analysis is implemented in the entire coronary arterial tree of diastolically arrested, vasodilated pig heart that takes into account vessel compliance and blood viscosity in each vessel of a large-scale simulation involving millions of vessels. The feed hematocrit (Hct) is varied at the inlet of the coronary arterial ...
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