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Chemokines and receptors in HIV encephalitis 总被引:1,自引:0,他引:1
VJ Sanders CA Pittman MG White G Wang CA Wiley CL Achim 《Canadian Metallurgical Quarterly》1998,12(9):1021-1026
BACKGROUND: Chemokines are involved in the migration of leukocytes and have been implicated in several inflammatory diseases of the central nervous system. Some of their receptors have been proposed to mediate HIV infection. OBJECTIVE: To determine changes in chemokine and receptor expression in HIV encephalitis, and to determine whether upregulation leads to recruitment of infected monocytes across the blood-brain barrier and participates in HIV neuropathology. METHODS: Immunocytochemistry and double-label immunofluorescent laser confocal microscopy was performed with antibodies to chemokines and their receptors on brain tissues from patients who died with or without HIV encephalitis. In vivo distribution was compared with in vitro cultures of human neuroglial cells. RESULTS: The beta-chemokines monocyte chemotactic protein-1, macrophage inflammatory protein-1alpha, and RANTES were detected on brain macrophages. Their presence was associated with the histopathological signs of HIV encephalitis. The alpha-chemokines IP-10 (10 kDa inflammatory protein) and interleukin-8 were expressed by astrocytes in all tissues, including controls. Presence of the CXC-chemokine receptor (CXCR)-4 was seen on brain macrophages/microglia, neurons, and astrocytes. CC-Chemokine receptor (CCR)-5 was detected only on macrophages/microglia. CCR-3 and CCR-1 were expressed by macrophages and endothelial cells. In vitro studies examining the presence of CCR-3, CCR-5, and CXCR-4 on human brain cell cultures demonstrated abundant neuronal and microglial expression. CONCLUSIONS: Expression of a variety of chemokines and receptors was shown to be increased in HIV encephalitis brain tissues particularly in areas of neuroglial reaction. The expression pattern supported their involvement in the recruitment of inflammatory infiltrates and formation of microglial nodules. Presence of chemokine receptors on neurons may be involved in the pathogenesis of neurologic damage in AIDS patients. 相似文献
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The dose that prevents the sympathetic response to a painful stimulation has been determined for alphaxolone and thiopentone (DRSM). The stimulation was the tracheal intubation and the sympathetic response has been evaluated as the percentual change of heart rate from the basal level. The DRSM has been determined as the dose that assures no percentual change of H.R. after intubation. The alphaxolone showed a DRSM very low (0.489) on the contrary the dose of thiopentone required to obtain no sympathetic response is high (7.776). 相似文献
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A rare form of injury to the distal tibial growth plate is described. Only two patients with such an injury have been reported previously. The injury, rotational displacement of the distal tibial epiphysis with posterior displacement of the fibula but without fracture, can be reduced easily and appears to have no lasting ill-effects. 相似文献
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The dopamine transporter mediates the reinforcing effects of cocaine, thus playing a central role in human cocaine addiction, and perhaps providing the mechanism for inducing the effects of prenatal cocaine exposure. This possibility has stimulated growing interest in the normal and abnormal development of this transporter. [3H]WIN 35,428 is a cocaine analog that is useful for studying the distribution and density of the dopamine transporter in striatum and other brain regions. The postnatal development of the dopamine transporter in the rat striatum was measured by quantitative autoradiography with [3H]WIN 35,428. Dopamine transporter levels were low at birth, increased through day 15, followed by much more rapid growth in late postnatal development. The majority of the transporter sites appeared after day 15. Lateral to medial and anterior to posterior gradients in transporter density were established early during development, and there was also an early concentration of transporter in striosomes that became difficult to identify by day 15. Differences between the developmental patterns described here and studies using other ligands for the dopamine transporter suggest there are significant differences in the transporter binding sites for these drugs. These differences in transporter ligand binding characteristics may reflect developmental changes in post-translational modification of the transporter and/or changes in the functional activity rather than simply the presence of the transporter. 相似文献