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141.
GUO Wen-yi YANG Yong JIA Guo-liang ZHANG Rong-qing ZHANG Qing LI Jing-xia GAO Hao-kao 《园艺学报》2005,21(1):72-76
AIM: To examine the effects of L-carnitine on apoptosis and oxidant injury in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenation and its possible mechanism. METHODS: The cultured cardiomyocytes were divided into three groups, control, A/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine treatment group, in which cells were exposed to 20 mg/L, 50 mg/L, 100 mg/L, 200 mg/L L-carnitine respectively at 2 h before anoxia. The superoxide dismutase (SOD), succinate dehydrogenase (SDH) activities and malondialdehyde (MDA) content were examined, and the apoptosis was determined by flow of cytometry (FCM). In addition, the ultrastructure was observed by transmission electron microscopy. RESULTS: In A/R group, SOD and SDH activities were lower, the apoptosis rate and MDA content were higher than those in control group (P<0.05). In L-carnitine treatment group, SOD and SDH activities were higher, the apoptosis rate and MDA content were lower than those in A/R group, a L-carnitine concentration-dependent effect was found. Moreover, impairment of myocardial ultrastructure was more severe in A/R group than L-carnitine treatment group. CONCLUSION: L-carnitine can protect cardiomyocytes against hypoxia/reoxygenation-induced injury in a dose-dependent manner. 相似文献
142.
ZHANG Zhan JIA Li-ting HOU Lei WANG Xue-mei CHANG Cai-hong YANG Ru-jing ZHANG Xi LIU Sheng-hong ZHENG Fang GONG Fei-li 《园艺学报》2005,21(12):2457-2461
AIM: To detect the effects of NK cells on the etiology of severe pre-eclampsia. METHODS: The peripheral blood and umbilical blood from severe pre-eclamptic patients and normal late pregnant women were collected. NK cells were seperated in percoll and counted by SAP. The proliferating ability of NK cells was measured by MTT and killing power of NK cells was determined by [51Cr] releasing test. The immunohistochemistry method was used to detect the quantity of NK cells and the expression of HLA-G in placenta of them. RESULTS: (1) Compared with that in normal late pregnant women, the counts of the NK cells in peripheral blood, umbilical blood and decidua of severe pre-eclamptic patients were significantly higher (all P<0.05). (2) Compared with that in normal late pregnant women, proliferating and killing ability of NK cells in peripheral blood and umbilical blood of severe pre-eclamptic patients were significantly higher. (3) The expression of HLA-G protein in placenta of severe pre-eclampsia group was lower than that in normal group (P<0.05). CONCLUSION: The quantity of NK cells in severe pre-eclamptic patients is increased with stronger biologic function. They may be related with the pathogenesis of severe pre-eclampsia. 相似文献
143.
AIM: To study the effects of intrathymic inoculation of liver specific antigen (LSA) on hepatocyte apoptosis after liver allotransplantation. METHODS: Orthotopic liver transplantation was used in this study. Group Ⅰ: syngenic control (Wistar-to-Wistar); Group Ⅱ: acute rejection (SD-to-Wistar); Group Ⅲ: thymus inoculation of SD rat LSA day 7 before transplantation. The observation of general situation and survival time, hepatocyte apoptosis and LAT expression in liver transplants were used to analyze immune state of animals in different groups. RESULTS: The general situation of group Ⅰ was very well after transplantation. Recipients of groupⅡ lost body weight progressively and all died within day 9 to day 13 post transplantation. As for group Ⅲ, the general situation of recipients was remarkably better than that in group Ⅱ. The positive cells of apoptosis in group Ⅲ detected by TUNEL were not significantly different from that in group Ⅰ, but was significantly lower than that in group Ⅱ. LAT was detected at any time in group Ⅱ with peak expression at day 5 and day 7 post transplantation. In contrast, LAT was not detected in any other groups. CONCLUSION: Intrathymic inoculation of LSA protects hepatocytes from apoptosis after liver allotransplantation. 相似文献
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146.
猪附红细胞体可溶性抗原的分析 总被引:2,自引:0,他引:2
为了解附红细胞体可溶性抗原的特性,本试验对解离下的猪附红细胞体,经超声波裂解制备粗抗原,再经SephadexG-200分离提纯后,应用对流免疫电泳(CIEP)定位特异性抗原蛋白峰,再进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)及免疫印迹(Westernblot),对猪附红细胞体粗提及纯化的可溶性抗原进行了分析。结果表明,猪附红细胞体可溶性抗原的电泳图谱上有四条蛋白带,其分子量分别为77Ku、62Ku、58Ku、29Ku,其中特异性抗原分子量为58Ku和29Ku。从而为附红细胞体抗原成分的进一步分析及该病的免疫学诊断等研究奠定了基础。 相似文献
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148.
CHENG He-xiang ZHOU Lian XU Ke-wei JIA Guo-liang WANG Hai-chang GUO Wen-yi ZHANG Rong-qing 《园艺学报》2006,22(10):1917-1921
AIM: To investigate the effects of constant magnetic field on apoptosis, secretion and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVEC), and their adhesion rates with THP-1 monocytes induced by angiotensin Ⅱ (AngⅡ).METHODS: The third passage of cultured HUVEC was used.There were six groups: control group, Ang Ⅱ (10-6 mol/L) group, Ang Ⅱ with 1, 5, 10 or 20 gausses of constant magnetic field group.Samples were collected 24 h after incubation with or without magnetic field.Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and propidinm iodide staining with flow cytometry.Secretion and expression of ICAM-1 and VCAM-1 were detected by ELISA and immunocytochemistry, respectively.Adhesion rate between HUVEC and THP-1 was measured by counting method.RESULTS: Ang Ⅱ at concentration of 10-6mol/L induced apoptosis in HUVECs (P<0.05 vs control), whereas in 1, 5, 10 and 20 gausses group, apoptosis of HUVECs was significantly lower than that in Ang Ⅱ group (P<0.05).Ang Ⅱ at concentration of 10-6 mol/L significantly increased secretion and expression of ICAM-1 and VCAM-1 (P<0.05 vs control), whereas secretion and expression of ICAM-1 and VCAM-1 in 1, 5, 10 and 20 gausses group significantly decreased, compared with Ang Ⅱ group (P<0.05).The adhesion rates between HUVEC and THP-1 significantly increased 24 h after incubation of HUVEC with Ang Ⅱ (P<0.05 vs control), in contrast, the adhesion rates between HUVEC and THP-1 in 1, 5, 10 and 20 gausses group significantly decreased, compaed with Ang Ⅱ group (P<0.05).CONCLUSIONS: One gauss to 20 gausses of constant magnetic field antagonizes the effects of Ang Ⅱ on HUVEC, decreases apoptosis and expression of ICAM-1 and VCAM-1 in HUVEC, and also decreases the adhesion rates between HUVEC and monocytes induced by Ang Ⅱ. 相似文献
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