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排序方式: 共有410条查询结果,搜索用时 15 毫秒
1.
目的 探讨人手术创伤腹膜组织中核转录因子Sp1激活 ,COL1A1和TIMP 1表达变化与腹膜纤维化之间的关系。方法 采用凝胶电泳迁移率改变分析法 (EMSA)检测手术创伤后不同时间的腹膜组织核转录因子Sp1的表达水平 ,WesternBlot检测COL1A1和TIMP 1蛋白表达 ,Masson染色观察腹膜组织中胶原纤维的变化。结果 Sp1在手术创伤后 0 .5h被活化 ,随着手术时间延长Sp1活性逐渐增强 ,至创伤后 4h时达高峰 ,同时创伤腹膜组织中的COL1A1和TIMP 1蛋白表达水平逐渐升高 ,存在差异显著性 (P <0 .0 1)。在手术创伤期内随手术时间的延长腹膜组织中胶原纤维增加。结论 核转录因子Sp1活化导致Ⅰ型胶原合成增加 ,细胞外基质降解减少 ,从而启动腹膜纤维化进程。 相似文献
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高糖对大鼠系膜细胞肝细胞生长因子受体表达的影响及其机制研究 总被引:1,自引:1,他引:0
目的 观察高糖作用下大鼠系膜细胞(MsC)肝细胞生长因子(HGF)受体c-Met的表达,并探讨其机制和意义。 方法 用RT-PCR和Western 印迹方法检测高糖作用大鼠MsC的不同时间点(0、12、24、48、96 h)c-Met的表达。分别用光辉霉素A(mithramycin A)和SU11274抑制转录因子Sp1的DNA结合活性和阻断c-Met。用电泳迁移率改变实验(EMSA)观察Sp1与c-Met基因启动子的结合活性。以荧光探剂二氯双氢荧光素二乙酸酯(DCFH-DA)捕获细胞内活性氧。 结果 大鼠MsC的c-Met表达在高糖作用12、24和48 h都明显上升,96 h开始下降。光辉霉素A呈浓度依赖性抑制高糖作用下大鼠MsC的c-Met表达上调。大鼠MsC内Sp1与c-Met基因启动子的结合活性在高糖作用下明显增强。HGF及c-Met显著抑制高糖诱导的大鼠MsC内活性氧的增多。 结论 高糖作用下大鼠MsC的c-Met表达增强,其机制可能是通过Sp1介导。HGF-c-Met信号通路激活能抑制高糖所致大鼠MsC内的氧化应激反应。 相似文献
3.
Glycodelin is a major secretory product of the uterine glandular epithelial cells of the human and non-human primate during the late luteal phase of the menstrual cycle and early pregnancy. Since progesterone levels are elevated during these periods we sought to determine how progesterone modulates glycodelin gene expression. Co-transfection of various deletions of the baboon glycodelin promoter with the progesterone receptor (PR) into Ishikawa cells, a human endometrial cell line, revealed that full progesterone responsiveness is retained within the region -119/+48. In COS-1 cells, a kidney cell line, progesterone failed to elevate luciferase levels when various deletion constructs and the PR were co-transfected. Mutation of the Sp1 site in the -67/+48 region lowered basal expression but did not affect the ability of progesterone to increase expression of the luciferase reporter in Ishikawa cells. These findings suggest that Sp1 sites are not involved in the progesterone regulation of the baboon glycodelin gene. We propose that progesterone induces a factor that regulates glycodelin gene expression in the uterus since we failed to obtain a similar response in a non-uterine cell line. 相似文献
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Sung-Hui Tseng Chun-Hsien Sung Lih-Geeng Chen Ying-Jang Lai Wei-Shun Chang Hsin-Ching Sung Ching-Chiung Wang 《Journal of ethnopharmacology》2014
Ethnopharmacological relevance
Velvet antlers (VA) have been claimed for centuries to have numerous medical benefits including strengthen bones. To investigate and compare the anti-osteoporotic activities from different sections of VA.Materials and methods
Fresh VA prepared from farmed sika deers (Cervus nippon) was divided into upper (VAU), middle (VAM), and basal (VAB) sections. The chemical constituents and anti-osteoporotic effect of different sections from VA were evaluated using ovariectomized rats.Results
Levels of water-soluble extracts, diluted alcoholic extract, amino acids, testosterone, insulin-like growth factor (IGF)-1and testosterone plus estradiol significantly differed among the different sections. Levels of these constituents were significantly higher in the upper section than in the basal section. Moreover, levels of testosterone and IGF-1 of the VAM were also significantly higher than those of the VAB. Calcium level increased downward from the tip with statistical significance. The strength of vertebrae increased in all VA-treated groups compared to the control, but only treatment with VAU and VAM increased the strength of the femur and the microarchitecure of the trabecular bone. Alkaline phosphatase levels of VAU- and VAM-treated groups significantly decreased, but osteocalcin did not significantly change. Moreover, VAU and VAM dose-dependently increased proliferation and mineralization of MC3T3-E1 cells.Conclusion
Our study provides strong evidence for the regional differences in the effectiveness of velvet antler in treating osteoporosis. However, further studies are needed to elucidate the bioactive chemical constituents associated with the anti-osteoporotic effects of velvet antler. 相似文献7.
Zhang Y Li XL Lai WP Chen B Chow HK Wu CF Wang NL Yao XS Wong MS 《Journal of ethnopharmacology》2007,109(1):165-169
The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats. 相似文献
8.
目的:观察转录因子 Sp1在 NK/T 细胞淋巴瘤(NK/TCL)细胞株中的表达及其对细胞侵袭的影响。方法采用实时荧光定量聚合酶链反应(PCR)、免疫荧光和 Western blot 法测定 NK/TCL 细胞株 SNK-1、SNK-6和健康人 NK 细胞中 Sp1的表达;采用 Sp1抑制剂光神霉素 A(MIT)作用于 NK/TCL细胞株后,用实时荧光定量 PCR 和 Western blot 法检测 Sp1、胰岛素样生长因子1受体(IGF-1R)和基质金属蛋白酶2(MMP-2)的表达;采用 Transwell 实验观察 MIT 对细胞侵袭力的影响。结果 NK/TCL 细胞株SNK-1、SNK-6中 Sp1基因和蛋白高表达。其中基因的表达水平分别是健康人 NK 细胞的(9.4±0.3)倍和(10.6±0.3)倍(P=0.0052,P=0.0037),蛋白的表达水平分别是健康人 NK 细胞的(5.4±0.3)倍和(8.6±0.5)倍(P=0.0083,P=0.0069)。100 nmol/L MIT 抑制 Sp1后,与二甲基亚砜处理的对照组相比,细胞株中 IGF-1R 的基因表达量分别下降了(83.9±3.7)%和(65.8±4.2)%(P=0.0082,P=0.0097),蛋白表达量分别下降了(51.5±7.1)%和(49.6±9.1)%(P=0.0178,P=0.0155)。100 nmol/L MIT 处理细胞后 SNK-1、SNK-6细胞的侵袭率分别下降了(29.6±6.4)%和(37.2±7.6)%(P=0.0418,P=0.0372),MMP-2蛋白表达量分别是对照组蛋白表达量的(52.7±4.7)%、(29.7±5.6)%(P=0.0286,P=0.0202)。结论 NK/TCL细胞株高表达 Sp1,其可能通过正调控 IGF-1R 增强 MMP-2的表达,进而提高 NK/TCL 细胞的侵袭力。 相似文献
9.
《Acta biomaterialia》2014,10(8):3557-3562
In the present study, the structure of two allogeneic and three xenogeneic bone blocks, which are used in dental and orthopedic surgery, were histologically analyzed. The ultimate goal was to assess whether the components postulated by the manufacturer can be identified after applying conventional histological and histochemical staining techniques. Three samples of each material, i.e. allogeneic material-1 and -2 as well as xenogeneic material-1, -2 and -3, were obtained commercially. After decalcification and standardized embedding processes, conventional histological staining was performed in order to detect inorganic matrix, cellular or organic matrix components. Allogeneic material-1 showed trabecular bone-like structures, which were free of cellular components as well as of organic matrix. The allogeneic material-2 showed trabecular bone structures, in which connective tissue and cellular remnants were embedded. Additionally, some connective tissue, which resembled fat-like tissue, was found within this material. The xenogeneic material-1 showed trabecular bone-like structures and contained organic components comparable to that demonstrated for the allogeneic material-2. The xenogeneic material-2 showed trabecular bone structures with single cells located in lacunae. The xenogeneic material-3 also showed trabecular structures. Neither cellular nor organic matrix components were found within this material. According to the data of the present study, the allogeneic material-1 and the xenogeneic material-3 were the only investigated materials for which the obtained histological data were in accordance with the manufactureŕs advertised information. The remaining three materials showed discrepancies—although the manufacturers of all five bone substitute materials stated that their blocks were free of organic/cellular remnants. These data are of great clinical and material science interest. It seems that even patented processing techniques are not always able to deliver reproducible materials. Although the manufacturers of all five bone blocks stated that their blocks were free of organic/cellular remnants, our histological analysis revealed that three out of five bone blocks did contain such remnants. Such specimens might be able to induce an immune response within the recipient. 相似文献
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