Se malt cakes containing 300μg selenium were taken up daily to men from high risk area in lung cancer and the influences of Ultraviolet (UV) and Benaopyrene (BαP) induced unscheduled DNA synthesis (UDS) were determi...Se malt cakes containing 300μg selenium were taken up daily to men from high risk area in lung cancer and the influences of Ultraviolet (UV) and Benaopyrene (BαP) induced unscheduled DNA synthesis (UDS) were determined. The Se levels in serum, hair and activity of GSH-px were increased by 89%, 67% and 178%, respectively, after Se-supplementation for half year. In the UV treatment, the ratio of UDS was decreased from the mean values of 2. 47 in the control to 1. 61 (P<0. 05) in the Se-group, In the BaP treatment, furthermore, the elevated Se levels of 78% in serum and 83% in the hair accompanied with 56% high in activity of GSH-px were followed by the Se intake for one year, while the mean value of UDS was reduced from 2. 21 in the control to 1. 47(P< 0. 05) in the group of selenium tested. The blocking effects of UV irradiation and BaP treatment induced UDS of peripheral lymphocytes were showed in the Se-supplementation.展开更多
背景与目的:进一步明确镉对人类细胞DNA的损伤效应以及对损伤修复的干扰作用。材料与方法:利用简化人全血细胞检测法研究了CdCl2诱导人全血细胞(主要是淋巴细胞和单核细胞参与反应)程序外:DNA合成(unscheduled DNA synthesis,UDS)的能...背景与目的:进一步明确镉对人类细胞DNA的损伤效应以及对损伤修复的干扰作用。材料与方法:利用简化人全血细胞检测法研究了CdCl2诱导人全血细胞(主要是淋巴细胞和单核细胞参与反应)程序外:DNA合成(unscheduled DNA synthesis,UDS)的能力及其对该细胞经N-甲基-N'-硝基-亚硝基胍(MNNG)或紫外线(UV)处理后DNA修复合成的影响。结果:0.1-10 μmol/L的CdCl2单独作用,细胞DNA修复合成前体物3H-TdR的掺入量与镉浓度量呈高度正相关的剂量-效应关系,其中10μmol／L剂量组与对照组相比差异有显著性;CdCl2在对人全血细胞UDS无明显诱导的剂量水平下即可使MNNG作用后DNA的修复合成受抑;与之相反,1μmol／L CdCl2与UV共同作用对人全血细胞UDS的诱导存在明显的协同作用。结论:较高浓度的镉对DNA具有损伤作用;而在较低浓度下,镉干扰DNA修复过程的作用较明显。上述直接和间接的遗传毒作用可能是镉致癌的机制之一。展开更多
通过将人全血细胞在体外3h 短期培养,同时用羟基脲(10mmol)抑制 S 期半保留 DNA 复制,以盐酸氮芥作用于细胞,用~3H-TdR 掺入,以液闪计数法,研究程序外 DNA 合成(UDS)。结果表明,全血短期培养淋巴细胞能显示较好的 UDS 反应,并与作用物...通过将人全血细胞在体外3h 短期培养,同时用羟基脲(10mmol)抑制 S 期半保留 DNA 复制,以盐酸氮芥作用于细胞,用~3H-TdR 掺入,以液闪计数法,研究程序外 DNA 合成(UDS)。结果表明,全血短期培养淋巴细胞能显示较好的 UDS 反应,并与作用物盐酸氮芥的浓度有良好的剂量效应关系。对117例健康人 UDS 的测定表明,男女性 UDS 反应无显著性差别(P>0.05),但 UDS 反应随年龄增高而增加(P<0.01)。正常人与恶性肿瘤患者的 UDS 值,差别不显著。展开更多
以盐酸氮芥和紫外线诱导27例治疗前白血病患者和13例正常人外周血白细胞非程序DNA合成(Unscheduled DNA Synthesis,简称UDS),结果表明:白血病患者外周血白细胞UDS值比正常人显著增高(P<0.001),提示:白血病患者DNA损伤修复功能显著增...以盐酸氮芥和紫外线诱导27例治疗前白血病患者和13例正常人外周血白细胞非程序DNA合成(Unscheduled DNA Synthesis,简称UDS),结果表明:白血病患者外周血白细胞UDS值比正常人显著增高(P<0.001),提示:白血病患者DNA损伤修复功能显著增高。这可能与白血病患者外周血中有较多的白血病细胞有关。展开更多
A diverse range of endocrine disrupting chemicals (EDCs) was examined, using an in vitro test system, for critical events required for the onset of carcinogenesis in vivo. The initiation stage of carcinogenesis is a g...A diverse range of endocrine disrupting chemicals (EDCs) was examined, using an in vitro test system, for critical events required for the onset of carcinogenesis in vivo. The initiation stage of carcinogenesis is a genotoxic process. 4-Octylphenol (alkylphenol), bisphenol A (plasticiser), coumestrol and genistein (phytoestrogens), 2,4-dichlorophe- noxyacetic acid and toxaphene (pesticides) and ethinylestradiol (synthetic hormone) were investigated for potential mutagencicity, DNA strand breakage, clastogenicity and DNA repair. Significant induction in the percentage of cells containing micronuclei was observed for all the EDCs. Toxaphene and coumestrol were mutagenic in the Ames assay. They also induced significant levels of unscheduled DNA synthesis and DNA strand breakage. Bisphenol A induced low level DNA strand breakage in HepG2 cells in the comet assay. The EDCs, with the exception of toxaphene, induced transcriptional activation in the yeast estrogen screen (YES) assay. They were potently oestrogenic in the mammalian based MVLN (transactivation) and E-SCREEN (proliferation) assays. This report on the transactivational, proliferative and genotoxic ability of the EDCs suggests that these chemicals may play a role in the etiology of male and female reproductive cancers.展开更多
文摘Se malt cakes containing 300μg selenium were taken up daily to men from high risk area in lung cancer and the influences of Ultraviolet (UV) and Benaopyrene (BαP) induced unscheduled DNA synthesis (UDS) were determined. The Se levels in serum, hair and activity of GSH-px were increased by 89%, 67% and 178%, respectively, after Se-supplementation for half year. In the UV treatment, the ratio of UDS was decreased from the mean values of 2. 47 in the control to 1. 61 (P<0. 05) in the Se-group, In the BaP treatment, furthermore, the elevated Se levels of 78% in serum and 83% in the hair accompanied with 56% high in activity of GSH-px were followed by the Se intake for one year, while the mean value of UDS was reduced from 2. 21 in the control to 1. 47(P< 0. 05) in the group of selenium tested. The blocking effects of UV irradiation and BaP treatment induced UDS of peripheral lymphocytes were showed in the Se-supplementation.
文摘背景与目的:进一步明确镉对人类细胞DNA的损伤效应以及对损伤修复的干扰作用。材料与方法:利用简化人全血细胞检测法研究了CdCl2诱导人全血细胞(主要是淋巴细胞和单核细胞参与反应)程序外:DNA合成(unscheduled DNA synthesis,UDS)的能力及其对该细胞经N-甲基-N'-硝基-亚硝基胍(MNNG)或紫外线(UV)处理后DNA修复合成的影响。结果:0.1-10 μmol/L的CdCl2单独作用,细胞DNA修复合成前体物3H-TdR的掺入量与镉浓度量呈高度正相关的剂量-效应关系,其中10μmol／L剂量组与对照组相比差异有显著性;CdCl2在对人全血细胞UDS无明显诱导的剂量水平下即可使MNNG作用后DNA的修复合成受抑;与之相反,1μmol／L CdCl2与UV共同作用对人全血细胞UDS的诱导存在明显的协同作用。结论:较高浓度的镉对DNA具有损伤作用;而在较低浓度下,镉干扰DNA修复过程的作用较明显。上述直接和间接的遗传毒作用可能是镉致癌的机制之一。
文摘以盐酸氮芥和紫外线诱导27例治疗前白血病患者和13例正常人外周血白细胞非程序DNA合成(Unscheduled DNA Synthesis,简称UDS),结果表明:白血病患者外周血白细胞UDS值比正常人显著增高(P<0.001),提示:白血病患者DNA损伤修复功能显著增高。这可能与白血病患者外周血中有较多的白血病细胞有关。
文摘A diverse range of endocrine disrupting chemicals (EDCs) was examined, using an in vitro test system, for critical events required for the onset of carcinogenesis in vivo. The initiation stage of carcinogenesis is a genotoxic process. 4-Octylphenol (alkylphenol), bisphenol A (plasticiser), coumestrol and genistein (phytoestrogens), 2,4-dichlorophe- noxyacetic acid and toxaphene (pesticides) and ethinylestradiol (synthetic hormone) were investigated for potential mutagencicity, DNA strand breakage, clastogenicity and DNA repair. Significant induction in the percentage of cells containing micronuclei was observed for all the EDCs. Toxaphene and coumestrol were mutagenic in the Ames assay. They also induced significant levels of unscheduled DNA synthesis and DNA strand breakage. Bisphenol A induced low level DNA strand breakage in HepG2 cells in the comet assay. The EDCs, with the exception of toxaphene, induced transcriptional activation in the yeast estrogen screen (YES) assay. They were potently oestrogenic in the mammalian based MVLN (transactivation) and E-SCREEN (proliferation) assays. This report on the transactivational, proliferative and genotoxic ability of the EDCs suggests that these chemicals may play a role in the etiology of male and female reproductive cancers.
