Erythrocyte deformability characteristics were assessed by passing red cell suspensions through Nuclepore polycarbonate filters having pore diameters of 3 ym. with pore lengths of 12 ym. During flow through these filters, at a constant flow rate of 2.17 cc/min., the pressure drop across the filter was monitored as a function of time. This measurement ...

To evaluate the rheological behavior of certain hemoglobinopathies with respect to oxygen tension, the concept of optimum hematocrit was employed. The optimum hematocrit is defined as the hematocrit at which the erythrocyte flow rate is the greatest. It therefore represents the optimum oxygen carrying capacity of blood. Using a Weissenberg Rheogoniometer ...

Monocyte adhesion to the endothelium is one of the earliest events leading to the pathogenesis of various inflammatory disorders like atherosclerosis. Since these interactions normally occur in flowing blood, it becomes essential to elucidate receptor mediated molecular mechanisms underlying monocyte-endothelial adhesion under physiologic flow ...

The effects of shear stress on polymorphonuclear leukocytes (PMNs) were investigated to ascertain whether mechanical trauma induces lysosomal granule release or membrane lysis. In addition, the effects of antiplatelet agents on PMN leukocyte response to shear stress were studied. The antiplatelet agents, known to elevate intracellular and cyclic ...

Microtubules form weakly associated networks with many properties similar to networks of rigid rods. To study the in vitro polymerization of bovine brain tubulin, a Fluids Rheometer was used in the oscillatory mode. The maximum elastic modulus for microtubule networks in the standard PIPES buffer was observed to be proportional to the tubulin ...

Mechanisms which trigger bone modeling/remodeling in response to changes in the mechanical environment are still unclear. In a three part study, effects of loading on osteoblast function were investigated using a three dimensional (3-D) ceWpolymer model. The 3-D model has advantages of cell culture while maintaining the natural matrix architecture ...

Tumor cell arrest and the formation of stable adhesive interactions between tumor cells and endothelial cells or underlying matrix in the microvasculature are crucial steps in the metastatic process. A sensitive hydrodynamic adhesion assay was used to investigate the regulation of melanoma cell adhesion stabilization to the extracellular matrix protein ...

The molecular mechanisms of binding interaction among von Willebrand factor, subendothelium and platelets under physiological shear conditions are important medically in hemostasis and thrombosis. By binding both subendothelial collagens and platelet surface receptors GPIbalpha, multimeric vWf acts as a bridge between subendothelium and circulating ...

Adhesion of malignant tumor cells under flow conditions to the endothelial monolayer lining the interior of the blood vessels is an important step in the metastatic cascade. This project examined the adhesive interactions of murine RAW117 large-cell lymphoma cells to murine hepatic sinusoidal endothelial cells (HSE). Flow cytometric analysis demonstrated ...

Endothelial cells line all of the vessels of the circulatory system, providing a non-thrombogenic conduit and form the principal barrier to the transport of substances between the blood and the surrounding tissue. The endothelial barrier is particularly important in the brain since neural function depends on the maintenance of a constant cererbro-spinal ...