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排序方式: 共有5722条查询结果,搜索用时 78 毫秒
991.
992.
Peter A. Walker Shinil K. Shah Fernando Jimenez Michael H. Gerber Hasen Xue Rochelle Cutrone Jason A. Hamilton Robert W. Mays Robert Deans Shibani Pati Pramod K. Dash Charles S. Cox Jr. 《Experimental neurology》2010,225(2):341-352
Recent investigation has shown an interaction between transplanted progenitor cells and resident splenocytes leading to the modulation of the immunologic response in neurological injury. We hypothesize that the intravenous injection of multipotent adult progenitor cells (MAPC) confers neurovascular protection after traumatic brain injury through an interaction with resident splenocytes, subsequently leading to preservation of the blood brain barrier.Four groups of rats underwent controlled cortical impact injury (3 groups) or sham injury (1 group). MAPC were injected via the tail vein at two doses (2 * 106 MAPC/kg or 10 * 106 MAPC/kg) 2 and 24 h after injury. Blood brain barrier permeability was assessed by measuring Evans blue dye extravasation (n = 6/group). Additionally, splenic mass was measured (n = 12/group) followed by splenocyte characterization (n = 9/group) including: cell cycle analysis (n = 6/group), apoptosis index (n = 6/group), cell proliferation (n = 6/group), and inflammatory cytokine measurements (n = 6/group). Vascular architecture was determined by immunohistochemistry (n = 3/group).Traumatic brain injury results in a decrease in splenic mass and increased blood brain barrier permeability. Intravenous infusion of MAPC preserved splenic mass and returned blood brain barrier permeability towards control sham injured levels. Splenocyte characterization indicated an increase in the number and proliferative rate of CD4+ T cells as well as an increase in IL-4 and IL-10 production in stimulated splenocytes isolated from the MAPC treatment groups. Immunohistochemistry demonstrated stabilization of the vascular architecture in the peri-lesion area.Traumatic brain injury causes a reduction in splenic mass that correlates with an increase in circulating immune cells leading to increased blood brain barrier permeability. The intravenous injection of MAPC preserves splenic mass and the integrity of the blood brain barrier. Furthermore, the co-localization of transplanted MAPC and resident CD4+ splenocytes is associated with a global increase in IL-4 and IL-10 production and stabilization of the cerebral microvasculature tight junction proteins. 相似文献
993.
Khawar Chaudhry Ryan Rogers Miao Guo Qin Lai Gunjan Goel Brandon Liebelt Xunming Ji Alecia Curry Aaron Carranza David F. Jimenez Yuchuan Ding 《Neuroscience letters》2010
Exercise preconditioning has been shown to reduce neuronal damage in ischemic/reperfusion (I/R) injury. ERK1/2 signaling in injury has been thought to modulate neuroprotection. In this study, we investigated the effects of ERK1/2 activation on the expression and activity of MMP-9 and downstream neuronal apoptosis. Adult male Sprague–Dawley rats were subjected to 30 min of exercise on a treadmill for 3 weeks. Stroke was induced by a 2-h middle cerebral artery (MCA) occlusion using an intraluminal filament. Apoptotic protein caspase-3 and neuronal apoptosis in cortex and striatum was determined by Western blot at 24 h reperfusion and TUNEL staining at 48 h reperfusion in 5 I/R injury groups: no treatment, MMP-9 inhibitor (doxycycline), pre-ischemic exercise, exercised animals undergone ERK1/2 inhibition (U0126), and dual inhibition of ERK1/2 and MMP-9 in exercised ischemic rats. Cerebral MMP-9 expression in ischemic rats with different treatment was determined at 6, 12 and 24 h reperfusion by real-time PCR for mRNA, Western blot for protein and zymography for enzyme activity. Exercise preconditioning significantly (p < 0.05) reduced apoptosis determined by caspase-3 and TUNEL. In non-exercised rats, doxycycline treatment had significant (p < 0.05) reductions in apoptosis after I/R injury. The dual ERK1/2–MMP-9 inhibited exercised animals had significantly (p < 0.05) reduced neuronal apoptosis that was similar to that seen in exercised ischemic rats. MMP-9 expression in I/R injury was significantly (p < 0.05) reduced in the exercised animals as compared to non-exercised controls. When ERK1/2 was inhibited, the reduced MMP-9 expression was reversed to the level seen in the non-exercised controls. This study has suggested that exercise-induced neuroprotection in I/R injury may be mediated by MMP-9 and ERK1/2 expression, leading to a reduction in neuronal apoptosis. 相似文献
994.
B. Liebelt P. Papapetrou A. Ali M. Guo X. Ji C. Peng R. Rogers A. Curry D. Jimenez Y. Ding 《Neuroscience》2010
Exercise preconditioning induces neuroprotection after stroke. We investigated the beneficial role of heat shock protein-70 (HSP-70) and phosphorylated extracellular-signal-regulated-kinase 1/2 (pERK 1/2), as they pertain to reducing apoptosis and their influence on Bcl-xL, Bax, and apoptosis-inducing factor (AIF) in rats subjected to ischemia and reperfusion. Adult male Sprague–Dawley rats were subjected to 30 min of exercise on a treadmill for 1, 2, or 3 weeks. Stroke was induced by a 2-h middle cerebral artery (MCA) occlusion using an intraluminal filament. Protein levels of HSP-70, pERK 1/2, Bcl-xL, Bax, and AIF were analyzed using Western blot. Neuroprotection was based on levels of apoptosis (TUNEL) and infarct volume (Nissl staining). Immunocytochemistry was used for cellular expression of HSP-70 and pERK 1/2. Significant (P<0.05) up-regulation of HSP-70 and pERK 1/2 after 3 weeks of exercise coincided with significant (P<0.05) reduction in neuronal apoptosis and brain infarct volume. Inhibition of either one of these two factors showed a significant (P<0.05) reversal in the neuroprotection. Bax and AIF were down-regulated, while levels of Bcl-xL were up-regulated in response to stroke after exercise. Inhibiting HSP-70 or pERK 1/2 reversed this resultant increase or decrease. Our results indicate that exercise diminishes neuronal injury in stroke by up-regulating HSP-70 and ERK 1/2. 相似文献
995.
996.
Hayes EC Dominguez CE Voelkel S Song M Shanti AS Murphy AA 《Fertility and sterility》2006,85(5):1553-1556
Glycodelin modulates vascular endothelial growth factor (VEGF) production in cumulus cells in vitro. Patients with normal gonadotropin responses who were undergoing IVF demonstrated increased VEGF production to glycodelin, whereas poor responders had a decreased response to glycodelin. 相似文献
997.
A placebo-controlled trial of pioglitazone in subjects with nonalcoholic steatohepatitis 总被引:1,自引:0,他引:1
998.
Canelas MM Bermejo JL Landi MT Requena C Guillen C Kumar R Nagore E 《Melanoma research》2012,22(4):316-319
A divergent pathway model to cutaneous melanoma is commonly accepted: sun sensitivity/chronic sun exposure and melanocytic instability. Although this dual model explains the development of most melanomas, clinical experience suggests other possible routes. The aim of this study was to explore the characteristics of patients who do not fit with these two pathways. We selected 818 patients with nonacral cutaneous melanoma and defined three groups: nevus-prone individuals, sun-sensitive individuals, and non-nevus-prone and non-sun-sensitive individuals. This group included patients without identifiable melanoma risk factors and comprised 52 patients (5.5% of the overall nonacral melanoma population). These patients were more frequently women, were more likely to present melanoma at a very young age (13.5% before 25 years), to have less frequent personal history of melanoma and remnants of pre-existing nevi, and to present tumors on the trunk and legs. We have identified a group of patients with fewer risk factors for melanoma that needs further studies to increase our understanding of melanoma development. 相似文献
999.
Higgins MJ Prowell TM Blackford AL Byrne C Khouri NF Slater SA Jeter SC Armstrong DK Davidson NE Emens LA Fetting JH Powers PP Wolff AC Green H Thibert JN Rae JM Folkerd E Dowsett M Blumenthal RS Garber JE Stearns V 《Breast cancer research and treatment》2012,131(3):915-924
Observational studies have demonstrated a decreased incidence of cancers among users of HMG CoA reductase inhibitors (statins) and a reduced risk of recurrence among statin users diagnosed with early stage breast cancer. We initiated a prospective study to identify potential biomarkers of simvastatin chemopreventive activity that can be validated in future trials. The contralateral breast of women with a previous history of breast cancer was used as a high-risk model. Eligible women who had completed all planned treatment of a prior stage 0-III breast cancer received simvastatin 40?mg orally daily for 24-28?weeks. At baseline and end-of-study, we measured circulating concentrations of high-sensitivity C-reactive protein (hsCRP), estrogens, and fasting lipids; breast density on contralateral breast mammogram; and quality of life by Rand Short Form 36-Item health survey. Fifty women were enrolled with a median age of 53?years. Total cholesterol, LDL cholesterol, triglyceride, and hsCRP fell significantly during the study (P values?0.001, <0.001, 0.003, and 0.05, respectively). Estrone sulfate concentrations decreased with simvastatin treatment (P?=?0.01 overall), particularly among post-menopausal participants (P?=?0.006). We did not observe a significant change in circulating estradiol or estrone concentrations, contralateral mammographic breast density, or reported physical functioning or pain scores. This study demonstrates the feasibility of short-term biomarker modulation studies using the contralateral breast of high-risk women. Simvastatin appears to modulate estrone sulfate concentrations and its potential chemopreventive activity in breast cancer warrants further investigation. 相似文献