Introduction The effects of mechanical force induced by fluid shear stress on the activity of several signal transduction pathways in endothelial cells is well documented (for a review, see Resnick and Gimbrone, Jr, 1995). Mechanical forces, such as those generated by fluid shear stress, are sensed at the cell surface (at adhesion points) by ␤1 and ␤3 integrins, and transduced through the cell ...

This review describes the role of bone cells and their surrounding matrix in maintaining bone strength through the process of bone remodeling. Subsequently, this work focusses on how bone formation is guided by mechanical forces and fluid shear stress in particular. It has been demonstrated that mechanical stimulation is an important regulator of bone metabolism. Shear stress generated by inter...

Blood vessels are subject to fluid shear stress, a hemodynamic factor that inhibits the mitogenic activities of vascular cells. The presence of nonuniform shear stress has been shown to exert graded suppression of cell proliferation and induces the formation of cell density gradients, which in turn regulates the direction of SMC migration and alignment. Here, we investigate the role of platelet...

Mechanical forces arising from strain, pressure, and fluid shear stress are sensed by cells through an unidentified mechanoreceptor(s) coupled to intracellular signaling pathways. In vascular endothelial cells, fluid shear stress is transduced via pathway(s) involving heterotrimeric guanine nucleotide-binding proteins (G proteins) by molecular mechanisms that are unknown. In the present study, ...

An analytical model of the fluid/cell mechanical interaction was developed. The interfacial shear stress, due to the coupling between the fluid and the cell deformation, was characterized by a new dimensionless number N(fs). For N(fs) above a critical value, the fluid/cell interaction had a damping effect on the interfacial shear stress. Conversely, for N(fs) below this critical value, interfac...

Background: The interaction between the blood and the vessel wall is of great clinical interest in studying cardiovascular diseases, the major causes of death in developed countries.Objective: To understand the effects of incorporating fluid-structure interaction into the simulation of blood flow through an anatomically realistic model of abdominal aorta and renal arteries reconstructed from CT...

Endothelial cells are the interface between hemodynamic fluid flow and vascular tissue contact. They actively translate physical and chemical stimuli into intracellular signaling cascades which in turn regulate cell function, and endothelial dysfunction leads to inflammation and diseased conditions. For example, atherosclerosis, a chronic vascular disease, favorably develops in regions of distu...

Endothelialization of artificial vascular grafts is rapid and complete in numerous animal models, including dogs and rats, but not in human patients. One possible explanation for this well-known, yet puzzling observation might be that monolayer formation of human endothelial cells (ECs), and of canine or rodent ECs, is affected differently by flow-induced shear stress. To begin testing this hyp...

An analysis of the effects of the turbulent shear stress on cell culture in a stirred tank microcarrier bioreactor system using a synergistic combination of computational fluid dynamic (CFD)-based simulations and experiments is presented. A 3D computational model of Corning’s benchscale spinner flask was built using a state-of-the-art computational fluid dynamics (CFD) software, Flow3D (www.flo...

Dense particulate suspensions exhibit a dramatic increase in average viscosity above a critical, material-dependent shear stress. This thickening changes from continuous to discontinuous as the concentration is increased. Using direct measurements of spatially resolved surface stresses in the continuous thickening regime, we report the existence of clearly defined dynamic localized regions of s...