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901.
Bone marrow mesenchymal stem cell (BMSC) transplantation represents a promising repair strategy following spinal cord injury (SCI), although the therapeutic effects are minimal due to their limited neural differentiation potential. Polydatin (PD), a key component of the Chinese herb Polygonum cuspidatum, exerts significant neuroprotective effects in various central nervous system disorders and protects BMSCs against oxidative injury. However, the effect of PD on the neuronal differentiation of BMSCs, and the underlying mechanisms remain inadequately understood. In this study, we induced neuronal differentiation of BMSCs in the presence of PD, and analysed the Nrf2 signalling and neuronal differentiation markers using routine molecular assays. We also established an in vivo model of SCI and assessed the locomotor function of the mice through hindlimb movements and electrophysiological measurements. Finally, tissue regeneration was evaluated by H&E staining, Nissl staining and transmission electron microscopy. PD (30 μmol/L) markedly facilitated BMSC differentiation into neuron‐like cells by activating the Nrf2 pathway and increased the expression of neuronal markers in the transplanted BMSCs at the injured spinal cord sites. Furthermore, compared with either monotherapy, the combination of PD and BMSC transplantation promoted axonal rehabilitation, attenuated glial scar formation and promoted axonal generation across the glial scar, thereby enhancing recovery of hindlimb locomotor function. Taken together, PD augments the neuronal differentiation of BMSCs via Nrf2 activation and improves functional recovery, indicating a promising new therapeutic approach against SCI.  相似文献   
902.
Mucosal tissues in the human female reproductive tract (FRT) are primary sites for both gynecological cancers and infections by a spectrum of sexually transmitted pathogens, including human immunodeficiency virus (HIV), that compromise women''s health. While the regulation of innate and adaptive immune protection in the FRT by hormonal cyclic changes across the menstrual cycle and pregnancy are being intensely studied, little to nothing is known about the alterations in mucosal immune protection that occur throughout the FRT as women age following menopause. The immune system in the FRT has two key functions: defense against pathogens and reproduction. After menopause, natural reproductive function ends, and therefore, two overlapping processes contribute to alterations in immune protection in aging women: menopause and immunosenescence. The goal of this review is to summarize the multiple immune changes that occur in the FRT with aging, including the impact on the function of epithelial cells, immune cells, and stromal fibroblasts. These studies indicate that major aspects of innate and adaptive immunity in the FRT are compromised in a site‐specific manner in the FRT as women age. Further, at some FRT sites, immunological compensation occurs. Overall, alterations in mucosal immune protection contribute to the increased risk of sexually transmitted infections (STI), urogenital infections, and gynecological cancers. Further studies are essential to provide a foundation for the development of novel therapeutic interventions to restore immune protection and reverse conditions that threaten women''s lives as they age.  相似文献   
903.
Microphysiological systems (MPS) are promising in vitro tools which could substantially improve the drug development process, particularly for underserved patient populations such as those with rare diseases, neural disorders, and diseases impacting pediatric populations. Currently, one of the major goals of the National Institutes of Health MPS program, led by the National Center for Advancing Translational Sciences (NCATS), is to demonstrate the utility of this emerging technology and help support the path to community adoption. However, community adoption of MPS technology has been hindered by a variety of factors including biological and technological challenges in device creation, issues with validation and standardization of MPS technology, and potential complications related to commercialization. In this brief Minireview, we offer an NCATS perspective on what current barriers exist to MPS adoption and provide an outlook on the future path to adoption of these in vitro tools.  相似文献   
904.
905.
目的:阐明病理性周期性张应力诱导人牙周膜细胞凋亡的分子机制。方法:人牙周膜细胞取自健康前磨牙,经过3?5代传代,细胞受到20%牵张力,时间为6 h或24 h,通过用膜联蛋白异硫氰酸荧光素(V-FITC)和碘化丙啶(PI)结合流式细胞仪检测细胞凋亡,用Western Blot法研究caspase-3,cleaved caspase-3,116 kDa PARP-1和85 k Da PARP-1蛋白的表达变化。结果:人PDL细胞受到病理性周期性张应力时存在凋亡,并以一种时间依赖的方式增加。受到病理性周期性张应力后裂解的caspase-3和PARP蛋白随着时间增加,然而抑制caspase-3的活性却可以抑制细胞的凋亡,但并不能抑制由其他通路导致的凋亡。结论:病理性周期性张应力通过caspase-3/PARP途径诱导人牙周膜细胞的凋亡。  相似文献   
906.
We previously showed that changes in calcium concentrations were related to cell apoptosis in vitro. The endoplasmic reticulum (ER) is the main component of calcium storage and signal transduction, and disrupting the balance of intracellular Ca2+ can cause endoplasmic reticulum stress (ERS). In this process, the ER releases stored Ca 2+ into the cytoplasm and activates calpain-2. To further investigate the effect of calpain in hepatic stellate cells (HSCs), in the current study, we examine the effect of N-acetyl-leu-leu-norleucinal (ALLN) on apoptosis resulting from calcium ionophore A23187–induced ERS. Our findings indicate that calpain inhibition reduces calcium ionophore A23187–induced apoptosis of HSCs and decreases the expression of ER stress proteins that may be related to the calpain/caspase signaling pathway.  相似文献   
907.
908.
909.
目的:探讨长春瑞滨联合卡铂化疗对晚期肺癌的治疗效果和安全性。方法:选取我院肿瘤科收治的晚期肺癌患者60例,根据不同治疗方案分为实验组与对照组,每组各30例患者。比较两组患者治疗前后的CEA、CA50、CYFRA21-1水平、白细胞计数及T淋巴细胞亚群CD4+、CD8+水平的变化。结果:治疗前,两组患者的CEA、CA50、CYFRA21-1水平、白细胞计数及T淋巴细胞亚群CD4+、CD8+水平比较均无统计学差异(P0.05)。治疗后,实验组的CEA、CA50、CYFRA21-1、CD8+水平均明显低于对照组,而白细胞计数及T淋巴细胞亚群CD4+、CD4+/CD8+水平均显著高于对照组,差异均具有统计学意义(P0.05)。结论:与放疗相比,长春瑞滨联合卡铂化疗能显著提高晚期肺癌的疗效,且不降低患者的细胞免疫。  相似文献   
910.
The expression of secretogranin III (SgIII) in chicken endocrine cells has not been investigated. There is limited data available for the immunohistochemical localization of SgIII in the brain, pituitary, and pancreatic islets of humans and rodents. In the present study, we used immunoblotting to reveal the similarities between the expression patterns of SgIII in the common endocrine glands of chickens and rats. The protein–protein interactions between SgIII and chromogranin A (CgA) mediate the sorting of CgA/prohormone core aggregates to the secretory granule membrane. We examined these interactions using co-immunoprecipitation in chicken endocrine tissues. Using immunohistochemistry, we also examined the expression of SgIII in a wide range of chicken endocrine glands and gastrointestinal endocrine cells (GECs). SgIII was expressed in the pituitary, pineal, adrenal (medullary parts), parathyroid, and ultimobranchial glands, but not in the thyroid gland. It was also expressed in GECs of the stomach (proventriculus and gizzard), small and large intestines, and pancreatic islet cells. These SgIII-expressing cells co-expressed serotonin, somatostatin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, or insulin. These results suggest that SgIII is expressed in the endocrine cells that secrete peptide hormones, which mature via the intragranular enzymatic processing of prohormones and physiologically active amines in chickens.  相似文献   
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