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101.
Hypoxia has been proposed as an important microenvironmental factor in the development of tissue fibrosis; however, the underlying mechanisms are not well defined. To examine the role of hypoxia-inducible factor-1 (HIF-1), a key mediator of cellular adaptation to hypoxia, in the development of fibrosis in mice, we inactivated Hif-1alpha in primary renal epithelial cells and in proximal tubules of kidneys subjected to unilateral ureteral obstruction (UUO) using Cre-loxP-mediated gene targeting. We found that Hif-1alpha enhanced epithelial-to-mesenchymal transition (EMT) in vitro and induced epithelial cell migration through upregulation of lysyl oxidase genes. Genetic ablation of epithelial Hif-1alpha inhibited the development of tubulointerstitial fibrosis in UUO kidneys, which was associated with decreased interstitial collagen deposition, decreased inflammatory cell infiltration, and a reduction in the number of fibroblast-specific protein-1-expressing (FSP-1-expressing) interstitial cells. Furthermore, we demonstrate that increased renal HIF-1alpha expression is associated with tubulointerstitial injury in patients with chronic kidney disease. Thus, we provide clinical and genetic evidence that activation of HIF-1 signaling in renal epithelial cells is associated with the development of chronic renal disease and may promote fibrogenesis by increasing expression of extracellular matrix-modifying factors and lysyl oxidase genes and by facilitating EMT.  相似文献   
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Aging is associated with loss of teeth, resorption of the alveolar process, and reduced tonicity of the facial muscles, leading to sunken cheeks and an unesthetic appearance. Esthetics in patients in need of complete dentures can be improved with the help of cheek plumpers to support the cheeks. They are noninvasive and straightforward to fabricate. Despite the reported success with the sole use of maxillary cheek plumpers, in certain situations, maxillary cheek plumpers provide inadequate support to the cheeks, evident in the lower third of the face. This clinical report describes a technique for fabricating detachable mandibular and maxillary cheek plumpers with 2 different types of attachment mechanisms.  相似文献   
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Metabolic Brain Disease - Obesity and dementia are two growing problems worldwide. Obesity act as a crucial risk factor for various diseases including Alzheimer’s disease (AD). Several...  相似文献   
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Purpose:To study clinical efficacy of valganciclovir in cytomegalovirus retinitis (CMVR) in human immunodeficiency virus (HIV)-positive-positive patients in a tertiary care clinic in a developing nation.Methods: In a retrospective study, systemic and ocular records of HIV patients suffering from CMVR and treated with valganciclovir, were analyzed. Primary outcome measures were involvement of the other eye, incidence of retinal detachment, systemic involvement, and mortality encountered. Secondary outcome measures included change in BCVA.Results: Out of nine patients who were included, two patients developed CMVR in the other eye and only one patient (11.11%) developed retinal detachment during the course of the study. No patient developed any systemic manifestations or had mortality during the course of the study. The change in BCVA was not statistically significant.Conclusion: Use of oral valganciclovir showed good outcome and was found to be a better alternative compared to the use of intravitreal ganciclovir in the literature. Introduction of valganciclovir at an affordable price in developing nations can decrease disease burden.  相似文献   
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Indium tin oxide thin films were deposited by magnetron sputtering on ceramic aluminum nitride substrates and were annealed at temperatures of 500 °C and 600 °C. The structural, optical, electrically conductive and gas-sensitive properties of indium tin oxide thin films were studied. The possibility of developing sensors with low nominal resistance and relatively high sensitivity to gases was shown. The resistance of indium tin oxide thin films annealed at 500 °C in pure dry air did not exceed 350 Ohms and dropped by about 2 times when increasing the annealing temperature to 100 °C. Indium tin oxide thin films annealed at 500 °C were characterized by high sensitivity to gases. The maximum responses to 2000 ppm hydrogen, 1000 ppm ammonia and 100 ppm nitrogen dioxide for these films were 2.21 arbitrary units, 2.39 arbitrary units and 2.14 arbitrary units at operating temperatures of 400 °C, 350 °C and 350 °C, respectively. These films were characterized by short response and recovery times. The drift of indium tin oxide thin-film gas-sensitive characteristics during cyclic exposure to reducing gases did not exceed 1%. A qualitative model of the sensory effect is proposed.  相似文献   
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The incidence of neonatal stroke is high and currently there are no strategies to protect the neonatal brain from stroke or reduce the sequelae. Agents capable of modifying inflammatory processes hold promise. We set out to determine whether delayed administration of one such agent, minocycline, protects the immature brain in a model of transient middle cerebral artery (MCA) occlusion in 7-day-old rat pups. Injury volume in minocycline (45 mg/kg/dose, beginning at 2 h after MCA occlusion) and vehicle-treated pups was determined 24 h and 7 days after onset of reperfusion. Accumulation of activated microglia/macrophages, phosphorylation of mitogen-activated protein kinase (MAPK) p38 in the brain, and concentrations of inflammatory mediators in plasma and brain were determined at 24 h. Minocycline significantly reduced the volume of injury at 24 h but not 7 days after transient MCA occlusion. The beneficial effect of minocycline acutely after reperfusion was not associated with changed ED1 phenotype, nor was the pattern of MAPK p38 phosphorylation altered. Minocycline reduced accumulation of IL-1beta and CINC-1 in the systemic circulation but failed to affect the increased levels of IL-1beta, IL-18, MCP-1 or CINC-1 in the injured brain tissue. Therefore, minocycline provides early but transient protection, which is largely independent of microglial activation or activation of the MAPK p38 pathway.  相似文献   
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