【摘要】 目的研究抗菌药物在亚抑菌浓度下对铜绿假单胞菌生物膜形成的影响。方法测定铜绿假单胞菌(PAE)对阿奇霉素、环丙沙星、阿米卡星和头孢他啶的MIC值;在96孔板和硅胶片上构建生物膜模型,结晶紫染色酶标仪测定OD值,并银染色光镜观察生物膜。结果阿奇霉素在L-肉汤培养基(LB)、水解酪蛋白胨肉汤培养基(MHB)中MIC分别为16、512mg/L,头孢他啶、环丙沙星及阿米卡星的MIC在MHB和LB中均为4、0.125、4mg/L;在MHB和LB培养基中,亚抑菌浓度阿奇霉素均促进铜绿假单胞菌生物膜形成,亚抑菌浓度的头孢他啶和环丙沙星在MHB和LB培养基中均抑制生物膜形成;在MHB中,阿米卡星浓度为0.25～4mg/L(1/16～1 MIC)时抑制生物膜形成,在浓度为0.125 mg/L(1/32 MIC)时促进生物膜形成,在LB中浓度为1～4mg/L(1/4～1MIC)时抑制生物膜形成,在浓度为0.25mg/L(1/16MIC)时促进生物膜形成,以上结果与对照组比较,差异均有统计学意义(P<0.05);银染色结果显示,阿奇霉素浓度为8mg/L时生物膜形成最多,其次是空白组,浓度为256mg/L时最少。结论不同培养条件下PAE浮游菌对阿奇霉素的敏感性不同;亚抑菌浓度的阿奇霉素促进PAE生物膜的形成;亚抑菌浓度环丙沙星、头孢他啶抑制生物膜形成;阿米卡星随亚抑菌浓度减小抑制作用减弱,在1/32、1/16MIC时可促进生物膜形成。更多还原

【Abstract】 OBJECTIVE To study the effects of the subinhibitory concentrations on the biofilm formation of Pseudomonas aeruginosa(PAE).METHODS We first determined the minimal inhibitory concentration of azithromycin,amikacin,ciprofloxacin and ceftazidime of the PAE cultured in MHB and LB.We made the static biofilm model of P.aeruginosa in 96-well microtiter plates with the four antibiotics and medical silica gel with the azithromycin concentration,the OD value was determined with crystal violet staining microplate reader,and the biofilm was observed with silver staining microscope.RESULTS The MIC of azithromycin of PAE in MHB and LB were 512 mg/L and 16 mg/L,respectively;the MIC of amikacin,ciprofloxacin and ceftazidime of the PAE were 4 mg/L,0.125 mg/L and 4 mg/L,respectively;the results of the static-made biofilm were as follows: in the MHB and LB media,azithromycin could induce the biofilm formation of PAE at the subinhibitory concentration.Ciprofloxacin and ceftazidime could inhibit the biofilm formation at these concentrations.Amikacin could inhibit the biofilm formation at the concentration of 0.25 to 4 mg/L(1/16MIC-MIC),but could induce biofilm formation at the concentration of 0.125 mg/L(1/16 MIC)in MHB;and when PAE was cultured in LB,amikacin could inhibit the biofilm formation at the concentration of 1 to 4 mg/L(1/4MIC-MIC),and induce the biofilm formation at 0.25 mg/L(1/16MIC).All the results above had statistical differences compared with the control group.Silver staining results: when the concentration of azithromycin was 8mg/L,the formation of the biofilm was the most,the second was the blank group and it was the least as the concentration was 256 mg/L.CONCLUSION The sensitivity of PAE planktonic bacteria to azithromycin varies in different culture condition;and the azithromycin may induce the biofilm formation at the subinhibitory concentration;ciprofloxacin and ceftazidime can inhibit the biofilm formation;the inhibitory of amikacin weakens as the subinhibitory concentration decreases and it can induce the biofilm formation at the concentration of 1/32 MIC and 1/16 MIC.更多还原