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51.
Anticancer Drug Resistance of HeLa Cells Transfected With Rat Glutathione S-transferase pi Gene 总被引:3,自引:0,他引:3
Cao W Zuo J Meng Y Wei Q Shi ZH Ju LM Fang FD 《Biomedical and environmental sciences : BES》2003,16(2):157-162
Objective To establish a cytologic expressing system of rat glutathione S-transferase pi (GST-pi) cDNA for detecting the resistance of HeLa cells to anticancer drugs. Methods The assessment was made with various anticancer drugs (adriamycin, mitomycin, cisplatinum and vincristine) that showed different cytotoxicities in transfectant HeLa cells with pSV-GT containing rat GST-pi cDNA (HeLa/pSV-GT) or control pSV-neo (HeLa/pSV-neo). Expression levels of GST-pi mRNA in HeLa/pSV-GT and HeLa/pSV-neo were measured by in situ hybridization using Digoxin-labelled cDNA probe. Results HeLa/pSV-GT expressed significantly high degree of GST-pi mRNA, whereas both HeLa/pSV-neo and HeLa cells had very low expression. Cytotoxicities of HeLa/pSV-GT and HeLa/pSV-neo with 4 anticancer drugs were measured by MTT assay. Drug concentrations for yielding 50% inhibition (IC50) in HeLa/pSV-GT by adriamycin, mitomycin and cisplatinum were 70.13μg/mL, 10.95μg/mL and 16.52μg/mE respectively. In contrast, IC50 in HeLa/pSV-neo was 10.34μg/mL, 7.48μg/mL and 13.70μg/mE respectively. The cytotoxicities of vincristine on both HeLa/pSV-GT and HeLa/pSV-neo were not significantly different. Conclusions Our findings suggest that HeLa/pSV-GT containing rat GST-pi cDNA is resistant to some anticancer drugs due to overexpression of GST-pi. Also, HeLa/pSV-GT cell line could serve as a useful cytogenetic model for further research. 相似文献
52.
目的 探讨合并伤对颅脑损伤病死率的影响及其急救原则。方法 总结分析我院收治的 4 311例颅脑损伤病例合并伤资料。结果 颅脑损伤 4 311例中合并伤 1372例 ( 31 8% ) ,其中轻型组 13 7% ,中型组 2 7 9% ,重型及特重型组 5 3 9%。各部位合并伤在总体、<2 4h死亡 ( 16 4例 )组、>2 4h死亡 ( 2 2 9例 )组中的发生率依次为 :颌面部 12 2 %、14 6 %、12 6 % ;胸部 9 3%、32 9%、10 9% ;腹部 1 5 %、9 1%、3 4 % ;脊柱骨盆 3%、2 1 9%、4 8% ;四肢 17 3%、2 0 1%、19 2 %。结论 在颅脑损伤患者的院前、院内急救中要加强对胸部、腹部、脊柱骨盆合并伤的合理救治 相似文献
53.
Objective: To observe the behavioral and biochemical effects of a traditional Chinese medicine Huanshao Dan (HSD) on learning and memory
deficits in transient cerebral ischemia model in mice.Methods: Step-through experiments, receptor binding test and choline acetyltransferase (ChAT) activities determination were performed.Results: Mice undertaken transient ischemia commited much more mistakes in step-through experiments and showed relatively higher3 H-MK801 binding in cerebral cortex and hippocampus than in sham operated animals. HSD decoction was most effective in reducing
these mistakes in mice. At the same time, and3 H-MK801 binding of cerebral cortex and hippocampus tissues were also significantly decreased, while ChAT activities in the
same tissues were increased.Conclusion: HSD might antagonize ischemic injury of brain through inhibition of glutamate N-methyl-D-Aspartic acid receptor overactivity.
ΔThis program was supported by National Nature Science Foundation of China (No.39421012) 相似文献
54.
Karl T. Kelsey Margaret R. Spitz Zheng-Fa Zuo John K. Wiencke 《Cancer causes & control : CCC》1997,8(4):554-559
The genes coding for separate isoforms of both the human glutathioneS-transferase class mu and class theta enzymes (GSTM1and GSTT1) arepolymorphic with a variable ethnic distribution. These enzymes detoxifyreactive epoxides, including carcinogens produced by tobacco smoke. Becauseof this, the null polymorphism in the GSTM1 gene (coding for the glutathioneS-transferase class mu enzyme) has been studied widely as a possible sourceof inherited susceptibility to smoking-related lung cancer. The more recentlydescribed null polymorphism in the GSTT1 gene also could contribute to anincreased risk of smoking-related lung cancer. As the incidence of lungcancer is known to differ by ethnicity, we have conducted a case-controlstudy in the United States of 108 African-Americans (Blacks) and 60Mexican-Americans (Hispanics) with lung cancer and 132 African-American(Black) and 146 Mexican-American (Hispanic) controls to investigate theassociation of the GSTT1 and GSTM1 polymorphi sms with lung cancer inminority populations. In the unadjusted data, there was a borderlinesignificant association of the GSTM1 null polymorphism with lung cancer inMexican-Americans (odds ratio [OR] = 1.8, 95 percent confidence interval [CI]= 1.0-3.3 ) that was not observed in African-Americans. The GSTT1 nullpolymorphism also had a higher prevalence in cases than controls in bothracial/ethnic groups, but this increase was not statistically significant.When the data were analyzed using logistic regression controlling for age,gender, race, and smoking, no significant association of either trait withlung cancer was observed, with ORs for both traits of approximately 1.3.However, when the prevalence of individuals who were null for bothpolymorphisms was compared by case status, a significant interaction wasobserved. Logistic regression models showed the OR for the association oflung cancer and the presence of both null polymorphisms compared with one(either GSTT1 or GSTM1) or no null genotype to be 2.9 (P < 0.04). Theseresults suggest that there may be carcinogenic intermediates in cigarettesmoke that are substrates for both the GSTT1 and GSTM1 enzymes, and that lungcancer risk is increased more than additively for individuals who have bothGSTT1 and GSTM1 null polymorphisms. 相似文献
55.
TheZiWuLiuZhu(I4gu)theoryofacupunctureandmoxibustionholdsthathumanqiandbloodcirculate,flowandebbinthetwelvechannelsfollowingacertainlawinthetraditionaltwelvetwo-hourperiodsofaday.Thisperiodical,directional,sequentialcirculationmakesfunctiona1activityofvis… 相似文献
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58.
目的:观察新鲜羊膜移植与自体球结膜移植治疗翼状胬肉的临床疗效。方法:随机将翼状胬肉患者分为A、B2组。A组30例(32眼)采用翼状胬肉切除联合新鲜羊膜移植。B组37例(40眼)采用翼状胬肉切除及自体球结膜移植。观察术后角膜愈合情况、角膜缘新生血管及角结膜是否有翼状胬肉样组织。结果:术后随访6~18mo,A组复发2眼(6%);B组复发3眼(8%)。结论:自体球结膜移植,取材方便,没有严重的并发症及排斥反应;新鲜羊膜移植损伤小,取材及处理相对复杂,但二者均能有效的减少翼状胬肉的术后复发,复发率相近。 相似文献
59.
60.
反义DNMT1、DNMT3b基因真核表达载体联合转染对人胆管癌细胞增殖和凋亡的影响 总被引:1,自引:0,他引:1
目的观察联合转染反义DNMT1、DNMT3b基因真核表达载体对人胆管癌细胞株QBC-939的增殖能力和细胞凋亡的影响。方法分别构建反义DNMT1基因和反义DNMT3b基因真核表达载体,脂质体介导法将二者先后转染入QBC-939,经G418筛选和荧光细胞克隆挑选得到稳定转染细胞株,并用Western blot检测转染前后的蛋白表达变化;用MTT法和软琼脂克隆形成试验观察各组细胞的增殖能力,流式细胞术检测细胞生长周期及凋亡率的变化。结果Western blot检测证实转染反义基因能使相应蛋白表达水平降低;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1基因能影响QBC-939的生长曲线,使细胞增殖减慢,并以前者为甚;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1基因的细胞克隆形成率分别为(6.78±0.89)%和(14.86±2.13)%,明显低于未转染组;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1能影响QBC-939的细胞周期,使之阻滞于G1期,细胞凋亡率从(1.63±0.27)%分别增加到(18.47±1.46)%和(6.19±0.78)%;在上述效应检测中,单独转染反义DNMT3b基因实验组对QBC-939细胞的生长无明显影响。结论通过联合转染反义DNMT1和DNMT3b基因真核表达载体,能抑制胆管癌细胞的生长和增殖,并促进凋亡的发生,其效果明显优于单独转染DNMT1反义基因;在DNA甲基化的过程中,DNMT1起着主要的作用,DNMT3b扮演着协同的角色,二者通过甲基化途径对胆管癌的发生发挥作用。 相似文献