Blood flow throughout the vascular circuit exerts a tangential force called shear stress upon all vessel walls. Under homeostatic conditions, shear stress is maintained within a narrow range. It has been shown that an alteration from this normal range of shear stress activates a biochemical signaling cascade in a process termed mechanotransduction. Although the signaling mechanism has not been ...

Atherosclerotic disease, and the subsequent complications of thrombosis and plaque rupture, has been associated with local shear stress. In the diseased carotid artery, local variations in shear stress are induced by various geometrical features of the stenotic plaque. Greater stenosis severity, plaque eccentricity (symmetry) and plaque ulceration have been associated with increased risk of cer...

Compared with the abdominal aorta, the hemodynamic environment in the inferior vena cava (IVC) is not well described. With the use of cine phase-contrast magnetic resonance imaging (MRI) and a custom MRI-compatible cycle in an open magnet, we quantified mean blood flow rate, wall shear stress, and cross-sectional lumen area in 11 young normal subjects at the supraceliac and infrarenal levels of...

The effects of NaCl (1 and 2%), added-water (AW; 30 and 40%), milk protein hydrolysate (MPH; 1, 2 and 3%), and end-point cooking temperature (EPT; 71.1 and 76.7 C) were examined. Regardless of the formulation, all turkey-beef frankfurters contained less than 0.4% fat. As levels of NaCl in the formula increased, the frankfurters had lower (P< 0.05) penetration values (total energy and peak force...

Background/aim: Endothelial dysfunction, tissue damage, inflammation, and microthrombosis are involved in the pathogenesis of pulmonary hypertension (PH), which may be present as a complication of congenital heart diseases. This study aims to identify how indicators of endothelial dysfunction (shear stress), tissue damage (brain natriuretic peptide and troponin T), inflammation (C-reactive prot...

Hemodynamic forces modulate various endothelial cell functions under gene regulation. Previously, we have shown that fibrinolytic activity of endothelial cells is enhanced by the synergistic effects of shear stress and cytokines. In this study, we investigated the effect of shear stress on tumor necrosis factor (TNF)-a–induced tissue factor (TF) expression in cultured human umbilical vein endot...

In the present paper the applicability of state and rate dependent friction laws in describing the phenomena of high speed slip at metal-on-metal interfaces is investigated. For the purpose of model validation, results of plate-impact pressure-shear friction experiments were conducted by Irfan in 1998 and Irfan and Prakash in 2000 using a Ti6Al4V and Carpenter Hampden tool-steel tribo pair are ...

Fluid shear stress alters the morphology and function of the endothelium by activating several kinases. Furthermore, shear stress potently inhibits apoptosis of endothelial cells. Since activation of Akt kinase has been shown to prevent cell death, we investigated the effects of shear stress on Akt phosphorylation. To test the hypothesis that shear stress interacts with the Akt kinase pathway, ...

BACKGROUND Atherosclerotic lesions are predominantly observed in curved arteries and near side branches, where low or oscillatory shear stress patterns occur, suggesting a causal connection. However, the effect of shear stress on plaque vulnerability is unknown because the lack of an appropriate in vivo model precludes cause-effect studies. METHODS AND RESULTS We developed a perivascular shea...

Hemodynamic shear stress alters the architecture and functions of vascular endothelial cells. We have previously shown that the synthesis of endothelin-1 (ET-1 ) in endothelial cells is increased by exposure to shear stress. Here we examined whether shear stress-induced alterations in cytoskeletal structures are responsible for increases in ET-1 synthesis in cultured porcine aortic endothelial ...