论文部分内容阅读
铜绿假单胞菌(PA)生物膜(BF)是持续感染的重要原因之一.本研究采用结合NCCLS标准的方法研究BF中PA的抗生素敏感性,主要研究了阿剂毒素对BF中PA抗生素敏感性的作用,为临床防治生物膜寻求潜在方法.本研究测定头孢服啶对悬浮状态和BF中座生PA(包括粘液型和非粘液型)的最小浓度(MPC).在非粘液型菌株,悬浮菌和BF菌均对头孢他啶敏感,加入4μg/ml阿剂毒素对头孢他啶的MBC影响较小;在粘液型菌株,头孢他啶对BF中的座生菌MBC增高,而加入4μg/ml阿剂毒素明显降低了头孢他啶的MBC,显示阿剂毒素增强了座生菌对头孢他啶的敏感性.“,”Pseudomonas aeruginosa (PA) biofilm (BF) is one of important factor of persistent infections. A method combined with the NCCLS standards for testing antimicrobial susceptibility of PA in BF is studied. Azithromycin is tested for its effect on susceptibility of PA in BFs in order to search a potential method for clinical prevention of BF. The MBCs of ceftazidime on planktonic or sessile PA (mucoid and nonmucoid) are tested. The effects of 4μg/ml azithromycin on the MBCs of ceftazidime are studied. Ceftazidime shows similar MIC on mucoid or nonmucoid strains in routine microbroth dilution test. In nonmucoid strains,both planktonic and sessile bacteria are sensitive to ceftazidime and 4μg/ml azithromycin shows little effect on the MBCs of ceftazidime while in mucoid strains, sessile bacteria in biofilms show high MBCs of ceftazidime and adding 4μg/ml azithromycin brings obvious reduction in MBCs of ceftazidime and enhance the sessile bacterial sensitivity to ceftazidime.