Search results
Results From The WOW.Com Content Network
Differences in vascular permeability between normal tissue and a tumor. Vascular permeability, often in the form of capillary permeability or microvascular permeability, characterizes the capacity of a blood vessel wall to allow for the flow of small molecules (drugs, nutrients, water, ions) or even whole cells (lymphocytes on their way to the site of inflammation) in and out of the vessel.
The permeability of a capillary wall is determined by the type of capillary and the surface of the endothelial cells. A continuous, tightly spaced endothelial cell lining only permits the diffusion of small molecules. Larger molecules and blood cells require adequate space between cells or holes in the lining.
Skin immunity is a property of skin that allows it to resist infections from pathogens. In addition to providing a passive physical barrier against infection, the skin also contains elements of the innate and adaptive immune systems which allows it to actively fight infections. Hence the skin provides defense in depth against infection.
Excessive or prolonged increases in permeability of the endothelium, as in cases of chronic inflammation, may lead to tissue swelling . Altered barrier function is also implicated in cancer extravasation. [6] Endothelial cells are involved in many other aspects of vessel function, including: Blood clotting (thrombosis and fibrinolysis).
Continuous capillaries are continuous in the sense that the endothelial cells provide an uninterrupted lining, and they only allow smaller molecules, such as water and ions, to pass through their intercellular clefts. [7] [8] Lipid-soluble molecules can passively diffuse through the endothelial cell membranes along concentration gradients. [9]
TP0965 causes endothelial barrier dysfunction, a hallmark of late-stage pathogenesis of syphilis. [34] It does this by reducing the expression of tight junction proteins, which in turn increases the expression of adhesion molecules and endothelial cell permeability, which eventually leads to disruption of the endothelial layer.
Treatment of hypertension and hypercholesterolemia may improve endothelial function in people taking statins (HMGCoA-reductase inhibitor), and renin angiotensin system inhibitors, such as ACE inhibitors and angiotensin II receptor antagonists. [28] [29] Calcium channel blockers and selective beta 1 antagonists may also improve endothelial ...
The skin microbiota is vital as a line of defense against infection, a physical barrier between the environment and the inside of the host. Commensal microbes that live on the skin, such as Staphylococcus epidermidis , produce antimicrobial peptides (AMPs) that aid the host immune system. [ 24 ]