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981.
982.
Aralkyl and aryl selenoglycosides as well as glycosyl selenocarboxylate derivatives were assayed on the activity of protein phosphatase-1 (PP1) and -2A (PP2A) catalytic subunits (PP1c and PP2Ac) in search of compounds for PP1c and PP2Ac effectors. The majority of tested selenoglycosides activated both PP1c and PP2Ac by ~2–4-fold in a phosphatase assay with phosphorylated myosin light chain substrate when the hydroxyl groups of the glycosyl moiety were acetylated, but they were without any effects in the non-acetylated forms. A peptide from the myosin phosphatase target subunit-1 (MYPT123–38) that included an RVxF PP1c-binding motif attenuated activation of PP1c by 2-Trifluoromethylbenzyl 2,3,4,6-tetra-O-acetyl-1-seleno-β-d-glucopyranoside (TFM-BASG) and 4-Bromobenzyl 2,3,4,6-tetra-O-acetyl-1-seleno-β-d-glucopyranoside (Br-BASG). MYPT123–38 stimulated PP2Ac and contributed to PP2Ac activation exerted by either Br-BASG or TFM-BASG. Br-BASG and TFM-BASG suppressed partially binding of PP1c to MYPT1 in surface plasmon resonance based binding experiments. Molecular docking predicted that the hydrophobic binding surfaces in PP1c for interaction with either the RVxF residues of PP1c-interactors or selenoglycosides are partially overlapped. Br-BASG and TFM-BASG caused a moderate increase in the phosphatase activity of HeLa cells in 1?h, and suppressed cell viability in 24?h incubations. In conclusion, our present study identified selenoglycosides as novel activators of PP1 and PP2A as well as provided insights into the structural background of their interactions establishing a molecular model for future design of more efficient phosphatase activator molecules.  相似文献   
983.
Mammary tissue from rats that had been ovariectomized and adrenalectomized 4 weeks previously was compared to that from intact rats in terms of epithelial content and hormone-responsiveness in vitro. The endocrinectomy resulted in about a 30% enlargement of the gland, but led to a loss of only about 12% of the epithelium. This estrogen-depleted epithelium was able to acquire full responsiveness in vitro to insulin in terms of the accumulation of alpha-aminoisobutyric acid, and induction of glucose-6-phosphate and gluconate-6-phosphate dehydrogenases. It was also fully responsive to cortisol in relation to the induction of NADH-cytochrome C reductase, and to prolactin in terms of total RNA synthesis. However, estrogen-depletion led to an 82% loss in the ability of a unit amount of the epithelium to synthesize casein in response to these 3 hormones, and to a similar loss in relation to the accumulation of 25K casein mRNA. Estrogen administration in vivo could prevent and reverse the casein lesion. The disparity between constitutive and casein hormone-responsiveness in the absence of estrogen is discussed in relation to cell commitment.  相似文献   
984.
The disrupted autoimmune response in Hashimoto’s thyroiditis (HT) has long been considered to be dominantly T helper type 1 (Th1) mediated. Recent advances in the field of immunology have introduced a new class of effector T cells, named ‘Th17’, which plays important roles in autoimmune disorders once thought to be merely Th1 mediated. We aimed to examine the levels of major Th17 cytokines in patients with HT in this study. We studied serum interleukin 17 (IL-17) and interleukin 23 (IL-23) levels in 46 newly diagnosed, untreated patients with HT (40 women and 6 men, aged 40.0 ± 11.8 years) divided into euthyroid (n = 22) and hypothyroid (n = 24) groups and compared them with age and sex matched 26 healthy euthyroid controls without HT (21 women and 5 men; aged 36.0 ± 12.9 years). Serum IL-17 and IL-23 levels were significantly different among euthyroid and hypothyroid HT patients and controls, with highest levels obtained in the euthyroid HT group (p = 0.041 for IL-17 and p < 0.001 for IL-23). TSH was negatively and FT4 was positively correlated with IL-17 (p = 0.016 for TSH and p = 0.004 for FT4) and IL-23 (p < 0.001 for TSH and p = 0.003 for FT4) levels. There were no correlations between thyroid volumes calculated on thyroid ultrasonography and IL-17 (p = 0.630) or IL-23 (p = 0.321) levels. In conclusion, the levels of IL-17, one of the major effector cytokines of the Th17 system, and IL-23, which had been implicated in the generation, survival and expansion of Th17 cells, are altered in HT. How thyroid hormone status and the course of disease affect Th17 system in chronic autoimmune thyroiditis needs to be determined with further studies.  相似文献   
985.
986.
目的:探讨5%环孢菌素霜对银屑病合并代谢综合征患者外周血IL-17、IL-18水平及PASI评分的影响。方法:选择我院收治的寻常型银屑病合并代谢综合症患者68例,分为实验组和对照组。对照组予以复方甘草酸苷和卡泊三醇治疗,实验组在此基础上加用制备好的5%环孢菌素霜,观察并比较两组患者治疗前后外周血IL-17及IL-18水平的变化情况以及血压、空腹血糖、血脂及PASI评分结果。结果:与治疗前比较,两组患者治疗后IL-17及IL-18水平、血压、FPG、TG及PASI评分均显著降低,而HDL-C明显升高,差异均具有统计学意义(P0.05);与对照组比较,实验组治疗后IL-17及IL-18水平、血压、FPG、TG及PASI评分较低,而HDL-C较高,差异均具有统计学意义(P0.05)。结论:5%环孢菌素霜辅助治疗可调节银屑病合并代谢综合征患者外周血IL-17、IL-18水平,降低其PASI评分,改善患者机体代谢紊乱状态,对银屑病合并代谢综合症有显著临床疗效。  相似文献   
987.
目的:探讨去整合素-金属蛋白酶17(ADAM17)在宫颈鳞状细胞癌中的表达及其临床病理意义。方法:运用免疫组织化学法分别检测正常宫颈上皮、宫颈鳞状细胞癌及宫颈上皮内瘤样变组织中ADAM17的表达,并分析其与宫颈癌临床分期及淋巴结转移的相关性。结果:ADAM17在正常宫颈上皮组织切片中无明显表达,在宫颈上皮内瘤样变组织中少部分表达,呈浅黄色,在宫颈鳞状细胞癌中癌细胞大量表达,ADAM17表达呈棕褐色,数量较多且浓染。不同临床分期的宫颈鳞状细胞癌组织中ADAM17的阳性表达率比较存在显著统计学差异(P0.05),且随临床分期的上升,ADAM17的表达逐渐升高;有淋巴结转移的宫颈鳞状细胞癌组织中ADAM17的阳性表达率显著高于无淋巴结转移的宫颈鳞状细胞癌组织,差异具有统计学意义(P0.05)。结论:ADAM17蛋白在宫颈鳞状细胞癌组织中呈异常高表达,且与宫颈鳞状细胞癌的临床分期和淋巴结转移密切相关,通过检测ADAM17蛋白的表达可能有助于宫颈鳞状细胞癌的诊断、治疗和预后预测。  相似文献   
988.
目的:探讨IL-17与IL-23在支气管哮喘患者血清中的表达水平及其相关性。方法:选择2010年2月~2015年9月在我院进行诊治的支气管哮喘患者98例,其中包括56例为缓解期组,42例为急性发作期组,对照组为20例体检健康者,观察三组的血清IL-17、IL-23水平及肺功能指标的差异,并分析其相关性。结果:与对照组相比,缓解期组和急性发作期组血清IL-17、IL-23水平均明显升高(P0.05),急性发作期组血清IL-17、IL-23水平均显著高于缓解期组(P0.05);急性发作期组患者的PEF%、FEV1%、V50%、V25%均明显低于缓解期组,差异有统计学意义(P0.05);哮喘患者血清IL-17水平与IL-23水平呈正相关(r=0.685,P=0.000),血清IL-17与FEV1负相关(r=-0.592,P=0.000)、与PEF负相关(r=-0.515,P=0.000),IL-23与FEV1负相关(r=-0.598,P=0.000),与PEF负相关(r=-0.532,P=0.000)。结论:血清IL-17和IL-23的高表达可能参与了支气管哮喘的形成,并能影响疾病的进程,两者表达水平密切相关。  相似文献   
989.
Heat shock protein 70 (Hsp70) preconditioning induces thermotolerance, and adenosine monophosphate (AMP)‐activated protein kinase (AMPK) plays a role in the process of autophagy. Here, we investigated whether 17‐dimethylaminoethylamino‐17‐demethoxy‐geldanamycin (17‐DMAG) protected against heat stroke (HS) in rats by up‐regulation of Hsp70 and phosphorylated AMPK (pAMPK). To produce HS, male Sprague–Dawley rats were placed in a chamber with an ambient temperature of 42°C. Physiological function (mean arterial pressure, heart rate and core temperature), hepatic and intestinal injury, inflammatory mediators and levels of Hsp70, pAMPK and light chain 3 (LC3B) in hepatic tissue were measured in HS rats or/and rats pre‐treated with 17‐DMAG. 17‐DMAG pre‐treatment significantly attenuated hypotension and organ dysfunction induced by HS in rats. The survival time during HS was also prolonged by 17‐DMAG treatment. Hsp70 expression was increased, whereas pAMPK levels in the liver were significantly decreased in HS rats. Following pre‐treatment with 17‐DMAG, Hsp70 protein levels increased further, and pAMPK levels were enhanced. Treatment with an AMPK activator significantly increased the LC3BII/LC3BI ratio as a marker of autophagy in HS rats. Treatment with quercetin significantly suppressed Hsp70 and pAMPK levels and reduced the protective effects of 17‐DMAG in HS rats. Both of Hsp70 and AMPK are involved in the 17‐DMAG‐mediated protection against HS. 17‐DMAG may be a promising candidate drug in the clinical setting.  相似文献   
990.
Epidemiologic data show the incidence of gastric cancer in men is twofold higher than in women worldwide. Oestrogen is reported to have the capacity against gastric cancer development. Endogenous oestrogen reduces gastric cancer incidence in women. Cancer patients treated with oestrogens have a lower subsequent risk of gastric cancer. Accumulating studies report that bone marrow mesenchymal stem cells (BMMSCs) might contribute to the progression of gastric cancer through paracrine effect of soluble factors. Here, we further explore the effect of oestrogen on BMMSCs‐mediated human gastric cancer invasive motility. We founded that HBMMSCs notably secrete interleukin‐8 (IL‐8) protein. Administration of IL‐8 specific neutralizing antibody significantly inhibits HBMMSCs‐mediated gastric cancer motility. Treatment of recombinant IL‐8 soluble protein confirmed the role of IL‐8 in mediating HBMMSCs‐up‐regulated cell motility. IL‐8 up‐regulates motility activity through Src signalling pathway in human gastric cancer. We further observed that 17β ‐estradiol inhibit HBMMSCS‐induced cell motility via suppressing activation of IL8‐Src signalling in human gastric cancer cells. 17β‐estradiol inhibits IL8‐up‐regulated Src downstream target proteins including p‐Cas, p‐paxillin, p‐ERK1/2, p‐JNK1/2, MMP9, tPA and uPA. These results suggest that 17β‐estradiol significantly inhibits HBMMSCS‐induced invasive motility through suppressing IL8‐Src signalling axis in human gastric cancer cells.  相似文献   
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