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Background  

In multiple sclerosis, inflammatory cells are found in both active and chronic lesions, and it is increasingly clear that cytokines are involved directly and indirectly in both formation and inhibition of lesions. We propose that cytokine mixtures typical of Th1 or Th2 lymphocytes, or monocyte/macrophages each induce unique molecular changes in glial cells.  相似文献   
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TRP(Transient receptor potentical)家族是非选择性阳离子通道家族,近来发现其与肾脏关系密切,如调节肾小管离子转运,肾脏微循环等。TRP通道异常可导致遗传性局灶节段硬化性肾病(FSGS),常染色体显性遗传多囊肾(ADPKD),低镁血症继发低钙血症(HSH)等,对TRP通道的进一步研究将有助于临床肾脏病的防治。  相似文献   
54.
Partial androgen insensitivity with sex phenotype variation in two unrelated families was associated with missense mutations in the androgen receptor (AR) gene that disrupted the AR NH(2)-terminal/carboxy terminal interaction. Each mutation caused a single amino acid change within the region of the ligand-binding domain that forms activation function 2 (AF2). In one family, the mutation I737T was in alpha helix 4 and in the other F725L was between helices 3 and 4. Neither mutation altered androgen binding as determined by assays of mutant AR in the patient's cultured genital skin fibroblasts or of recombinant mutant receptors transfected into COS cells. In transient cotransfection assays in CV1 cells, transactivation with the AR mutants at low concentrations of DHT was reduced several fold compared with wild-type AR but increased at higher concentrations. Defects in NH(2)-terminal/carboxy terminal interactions were identified in mammalian two hybrid assays. In similar assays, there was reduced binding of the p160 coactivators TIF2/SRC2 and SRC1 to the mutant AR ligand binding domains (LBD). In the family with AR I737T, sex phenotype varied from severely defective masculinization in the proband to a maternal great uncle whose only manifestation of AIS was severe gynecomastia. He was fertile and passed the mutation to two daughters. The proband of the F725L family was also incompletely masculinized but was raised as a male while his half-sibling by a different father was affected more severely and reared as a female. These studies indicate that the function of an AR AF2 mutant in male development can vary greatly depending on the genetic background.  相似文献   
55.
Jin H  Kang Y  Xiao C  Zhu K  Ma Y  Xie Q  Ma J  Xie Q  He C  Yang Z  Sun Z  Zhang X  Chen M  Zhang F  Wang B 《Viral immunology》2005,18(3):539-548
Prime-boost strategy has been exhibited its potency to enhance immune responses, which would be important to the success to develop a vaccine against the foot-and-mouth disease virus (FMDV). An eukaryotic expression construct encoding the FMDV capsid VP1 protein with a recombinant VP1 protein or a commercial FMDV vaccine were tested in the prime-boost strategy in mice and cattle trials. The levels of induced specific antibodies, T cell proliferations, and DTH activities were significantly higher in the prime-boost groups than in those vaccinated with DNA, protein or FMDV vaccine alone. More importantly, the levels of neutralizing antibodies in the former groups were significantly higher than others and could last for at least four months in cattle trials. This study suggests that the prime-boost strategy significantly improves the effective immunity and may provide a longer protection against FMDV infection.  相似文献   
56.
目的研究路氏乳杆菌(Lactobacillus reuteri,也称罗伊氏乳杆菌)JCM1081菌体表面蛋白对其黏附HT-29细胞的影响。方法将路氏乳杆菌JCM1081菌体进行胰蛋白酶、蛋白酶K处理;用氯化锂和盐酸胍对乳杆菌表面的蛋白进行抽提,进行SDS-PAGE后与黏蛋白受体进行Western blot,并对杂交阳性蛋白进行质谱分析鉴定。结果路氏乳杆菌JCM1081菌体经胰蛋白酶、蛋白酶K处理后,其对HT-29细胞的黏附力显著下降(P<0.01);用氯化锂去除路氏乳杆菌JCM1081菌体外表面的S层蛋白后,路氏乳杆菌JCM1081对HT-29细胞的黏附力无显著变化;Western blot结果显示相对分子质量(Mr)为29×103和14×103的两种菌体表面蛋白与黏蛋白受体杂交中出现了强阳性;质谱分析结果显示29×103蛋白与路氏乳杆菌ATCC55730的h0793蛋白相似性高达71.1%。结论路氏乳杆菌JCM1081菌体表面的蛋白参与了乳杆菌的黏附,其中29×103和14×103的两种胞壁表面蛋白能够特异地识别黏蛋白受体并与之结合,29×103蛋白属ABC转运蛋白家族。  相似文献   
57.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites.  相似文献   
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目的研究脂肪组织中高迁移率族蛋白B1(HMGB1)表达增加与妊娠期糖尿病(GDM)患者胰岛素抵抗程度及产后糖代谢异常的关系。方法选择2016年10月至2019年3月期间在海安市中医院诊断为GDM并接受剖宫产的126例患者作为GDM组,选择同期在该院接受剖宫产的健康孕妇150例作为对照组,检测剖宫产当天孕妇血清HMGB1、空腹胰岛素(FINS)的含量及脂肪组织中HMBG1、胰岛素受体底物(IRS)-1、IRS-2的表达水平,计算胰岛素抵抗指数(HOMA-IR)。随访产后1年内糖代谢异常的发生情况并绘制K-M曲线。结果GDM组患者脂肪组织中HMGB1的表达水平、血清HMGB1含量及FINS、HOMA-IR水平明显高于对照组(t值分别为14.496、16.503、19.068、13.446,P<0.05),脂肪组织中IRS-1、IRS-2的表达水平明显低于对照组(t值分别为11.616、10.596,P<0.05);GDM组患者脂肪组织中HMGB-1的表达水平与血清HMGB1、FINS的含量及HOMA-IR的水平呈正相关(r值分别为0.405、0.358、0.405,P<0.05),与脂肪组织中IRS-1、IRS-2的表达水平呈负相关(r值分别为-0.278、0.255,P<0.05);经K-M曲线分析,与GDM组中脂肪组织HMGB1低表达患者比较,HMGB1高表达患者产后1年糖代谢异常累积发生率明显升高(χ^(2)=3.933,P<0.05)。结论GDM患者脂肪组织中HMGB1表达增加与胰岛素抵抗的加重、产后糖代谢异常的发生有关。  相似文献   
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