Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three cl...Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three clinical strainsof M. hominis by broth microdilution method. The ac-cumulation of ciprofloxacin in M. hominis and the in-fluence of carbonyl cyanide m-chlorophenyl-hydrazone(CCCP) and reserpine were measured by a fluores-cence method. Results: Two resistant strains and two susceptiblestrains of M. hominis were selected in vitro. The accu-mulation of ciprofloxacin for resistant strains is lowerthan that of susceptible strains. CCCP and reserpinehad different influence on clinical strains of M.hominis. Reserpine could dramatically increase theaccumulation of ciprofloxacin, however CCCP had alittle effect on it. Conclusion: These results suggest that the pres-ence of an active efflux system implicated in thefluoroquinolones-resistant in M. hominis.展开更多
目的研究姜黄素对人食管癌细胞Eca-109细胞周期的影响及其作用机制。方法采用MTT法分析不同浓度姜黄素对Eca-109细胞增殖的影响,采用流式细胞术分析姜黄素对Eca-109细胞周期的影响,采用RT-PCR技术检测姜黄素对Eca-109细胞Cyc linB1mRNA...目的研究姜黄素对人食管癌细胞Eca-109细胞周期的影响及其作用机制。方法采用MTT法分析不同浓度姜黄素对Eca-109细胞增殖的影响,采用流式细胞术分析姜黄素对Eca-109细胞周期的影响,采用RT-PCR技术检测姜黄素对Eca-109细胞Cyc linB1mRNA表达的影响,采用W estern-b lotting方法检测姜黄素对Eca-109细胞Cyc lin B1蛋白表达的影响。结果 20,40,60μmol/L姜黄素均可明显抑制Eca-109细胞的增殖(P均<0.05),特别是姜黄素作用24 h后,随姜黄素浓度增加,Eca-109细胞的G0/G1期细胞比例明显下降而G2/M期细胞比例明显提高,Cyc lin B1蛋白与mRNA表达水平均降低,与对照组比较均有显著性差异(P均<0.01)。结论姜黄素可抑制Eca-109细胞增殖,使细胞周期阻滞,该作用可能与下调细胞Cyc lin B1表达有关。展开更多
基金Financially supported by a grant from the Education Committee of Hunan Province(No.00A009)
文摘Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three clinical strainsof M. hominis by broth microdilution method. The ac-cumulation of ciprofloxacin in M. hominis and the in-fluence of carbonyl cyanide m-chlorophenyl-hydrazone(CCCP) and reserpine were measured by a fluores-cence method. Results: Two resistant strains and two susceptiblestrains of M. hominis were selected in vitro. The accu-mulation of ciprofloxacin for resistant strains is lowerthan that of susceptible strains. CCCP and reserpinehad different influence on clinical strains of M.hominis. Reserpine could dramatically increase theaccumulation of ciprofloxacin, however CCCP had alittle effect on it. Conclusion: These results suggest that the pres-ence of an active efflux system implicated in thefluoroquinolones-resistant in M. hominis.
文摘目的研究姜黄素对人食管癌细胞Eca-109细胞周期的影响及其作用机制。方法采用MTT法分析不同浓度姜黄素对Eca-109细胞增殖的影响,采用流式细胞术分析姜黄素对Eca-109细胞周期的影响,采用RT-PCR技术检测姜黄素对Eca-109细胞Cyc linB1mRNA表达的影响,采用W estern-b lotting方法检测姜黄素对Eca-109细胞Cyc lin B1蛋白表达的影响。结果 20,40,60μmol/L姜黄素均可明显抑制Eca-109细胞的增殖(P均<0.05),特别是姜黄素作用24 h后,随姜黄素浓度增加,Eca-109细胞的G0/G1期细胞比例明显下降而G2/M期细胞比例明显提高,Cyc lin B1蛋白与mRNA表达水平均降低,与对照组比较均有显著性差异(P均<0.01)。结论姜黄素可抑制Eca-109细胞增殖,使细胞周期阻滞,该作用可能与下调细胞Cyc lin B1表达有关。
