Hkkk123 Začiatočník
Počet príspevkov : 73 Registration date : 22.01.2015
| Predmet: Bcl 2 targeting and chemoradiotherapy induced elimination of A375 melanoma St november 11, 2015 6:56 am | |
| At a fundamental level, according to the report of stroke progress group 2002, the neurovascular unit was defined as the molecular influences and cell signaling mechanisms that characterize the interactions between circulating blood elements and the blood KU-55933 臨床試験 vessel wall, extracellular matrix, glia, and neurons during ischemic and hemorrhagic stroke. Understanding the interactions between these neurovascular components can define the broad spectrum of events involved in the initiation and progression of ischemia, hemorrhage, brain inflammation, brain edema, BBB dysfunction and white matter changes post stroke. This fundamental definition of neurovascular unit also described the inter actions between blood vessel wall, glia and neurons and circulating blood elements, indicating the participation of peripheral immune system in the function of neuro vascular unit.<br><br> The brain is considered to be an immune privileged organ, where BBB functions to prevent infiltra tion of immune cells from the blood. However, leukocytes were observed to be present in embryonic and adult brain in normal physiological conditions. These neurovascular and gliovascular immune interactions gain more importance depending on the presence of perivascular buy Linifanib antigen presenting cells in the inner and outer wall of the astrocyte end feet and base ment membrane of endothelial cells in the perivascular space. This indicates that communication with sys temic immune compartment might also be a part of neurovascular and gliovascular functions. However, the physiological significance for these interactions is not clear.<br><br> Occlusion of blood flow to any region of the brain re sults in deprivation of oxygen, glucose and nutrients to the neurovascular and gliovascular units. This re sults LY3009104 1187594-09-7 in uncoupling of neurovascular and gliovascular units and in severe pathological alterations in the physical and physiological properties of these units. BBB breakdown re sults in exacerbation of vasogenic cerebral edema which is one of the most life threatening complications post stroke. This process is greatly intensified by the produc tion of astrocytic matrix metalloproteinases and by aquaporins in the astrocytic end foot process. Physical swelling of the astrocyte end feet process also contributes to increased BBB permeability indicating glio vascular uncoupling.<br><br> One of the most important fea tures in the neurovascular and gliovascular uncoupling during cerebral ischemia is the intercellular biochemical signaling that results in perturbations in BBB permeability. Furthermore, the disturbances in the vascular wall of neurovascular and gliovascular units also trigger vascular remodeling and angiogenesis which are consid ered to be endogenous adaptive events post stroke. Normal brain endothelium is relatively inert to sup port leukocyte interactions. However, ischemia results in a phenotypical change of resting brain endothelium to reactive endothelial phenotype thereby supporting the infiltration of leukocytes into the infarcted brain tissue. | |
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