【摘要】 目的研究阿奇霉素(azithromycin,AZM)联合亚胺培南(imipenem,IPM)对肺炎克雷伯菌生物膜(biofi lm,BF)的抑制作用。方法采用改良平板法建立肺炎克雷伯菌BF模型,微量稀释法测定抗菌药物的最低抑菌浓度,银染法快速鉴定细菌BF,噻唑蓝(MTT)比色法测定BF中的活菌数,棋盘设计法测定阿奇霉素和亚胺培南对BF的协同抑制作用,用RT-PCR对联合用药前后luxS基因的表达进行相对定量分析,检测结果采用SPSS13.0软件进行统计处理。结果加入1/16、1/4MIC阿奇霉素可显著增加1/4、1/2及1MIC亚胺培南对肺炎克雷伯菌BF的抑菌活性;加入1/4、1/2及1MIC的亚胺培南也可显著增加1/16、1/4MIC阿奇霉素的抑菌活性;1MIC IPM与1/4、1/16MIC AZM联合应用;1/2MIC IPM与1/4MIC AZM联合应用可以下调lux S基因的表达。结论阿奇霉素与亚胺培南联合使用可下调肺炎克雷伯菌lux S基因的表达,从而增强其对BF的抑菌活性。更多还原

【Abstract】 Objective To study the inhibitory activity of azithromycin(AZM) and imipenem(IPM) on the bacterial biofilm of Klebsiella pneumoniae(KP). Methods The improved plate method was adopted to establish the biofilm model of Klebsiel la pneumoniae. The minimal inhibitory concentrations(MIC) of antimicrobial drugs was determined by Micro-dilution method. Silver staining method was applied to rapidly identify the bacterial biofilm. Methyl thiazolyl tetrazolium(MTT) colorimetric method was performed to determine the number of living bacteria in biofilm; The board design method was used to observe the bacteriostatic activity of AZM and IPM. RT-PCR method was employed to relatively quantitate lux S gene expression. The results were analyzed by SPSS13.0 software. Results 1/16 and 1/4 MIC of AZM could significantly enhance the antibacterial activity of 1/4MIC、1/2MIC and 1MIC of IPM against Klebsiella pneumoniae biofilm. 1/4, 1/2 and 1MIC of IPM could enhance the bacteriostatic activity of 1/16 and 1/4MIC AZM. 1MIC of IPM used in combination with 1/4 and 1/16 MIC of AZM and 1/2MIC of IPM used in combination with 1/4MIC of AZM could significantly decreased the expression of lux S gene in biofilm-producing bacteria. Conclusion A combination of AZM and IPM could reduce the expression of lux S gene, so as to enhance its inhibitory activity to Klebsiella pneumoniae biofilm.更多还原