摘要
目的应用光动力抗菌化学疗法(Photodynamic Therapy,PACT)对3种临床常见耐药菌,耐甲氧西林金黄色葡萄球菌(MRSA)、多药耐药铜绿假单胞菌(multidrug-resistant Pseudomonsa aeruginosa,MDRP)、产超广谱β-内酰胺酶的大肠埃希菌(ESBLs+E.coli)的杀菌效果进行比较,并初步探索对菌膜形成的影响。方法应用3种耐药菌确定激光照射的最佳强度和光敏剂甲苯胺蓝(Toluidine blue O,TBO)的最适剂量范围。考察TBOPACT对3种耐药菌在活菌数和杀灭对数值的影响,及3种耐药菌对PACT敏感性的差异,并通过革兰染色和环境扫描电镜观察研究TBO-PACT对MRSA和MDRP生物膜的杀菌效果。结果单纯激光照射对3种耐药菌株的杀伤效果较弱,随着激光强度增加呈现一定的增强。加入TBO后可提高对细菌的杀伤效果(P<0.001)。然而,随TBO浓度增加,3种耐药菌株实验组的杀灭对数值先增后减,在TBO浓度为16.67μg/ml时均达到峰值;3种耐药细菌对PACT的敏感性依次为MRSA>ESBLs+E.coli>MDRP。光镜及电镜下的研究结果提示,PACT可抑制MRSA和MRDP菌膜的形成。结论 PACT对于耐药菌感染是有潜力的治疗方法,未来若用于临床难治性的创伤感染,可减少院内细菌耐药的发生。
OBJECTIVE To investigate the bactericidal effects of photodynamic antimicrobial chemotherapy（PACT）on three common multidrug-resistant（MDR）bacteria,including methicillin-resistant Staphylococcus aureus（MRSA）,multidrug-resistant Pseudomonsa aeruginosa（MDRP）and ESBLs-producing Escherichia coli（ESBLs~＋E.coli）,and the effects on the formation of biofilms.METHODS The optimal doses of light intensity and toluidine blue O（TBO）were determined using three MDR bacteria.Survival of bacteria and value of killing logarithm（KL）were measured to determine the antimicrobial efficacy of TBO-PACT on these MDR bacteria,and the sensitivity of bacteria to TBO-PACT were also detected.Gram staining and environmental scanning electron microscope（ESEM）were used to determine the antimicrobial efficacy of TBO-PACT for the biofilms of MRSA and MDRP.RESULTS The killing effects of single laser irradiation on 3 drug-resistant strains were weak,and showed a certain enhancement with the increase of laser intensity,and TBO could increase the killing effect of bacteria（P〈0.001）.However,with the increase of TBO concentration,the killing rates of the 3 drug resistant strains in the experimental group increased first and then decreased,and reached the peak value at TBO concentration of 16.67μg/ml.The order of sensitivity of 3 drug resistant bacteria to PACT was as the following：MRSA〉 ESBLs~＋E.coli〉 MDRP.The results with light and electron microscope suggested that the formation of MRSA and MRDP bacterial biofilms could significantly be inhibited by PACT.CONCLUSIONPACT is a potential treatment method for MDR bacterial infections.PACT would have opportunity to apply to clinical in refractory traumatic infection and can reduce the incidence of bacterial resistance in hospital in the future.
作者
彭莹莹
季晓春
王广芬
彭兆祥
葛海燕
PENG Ying-ying;JI Xiao-chun;WANG Guang-fen;PENG Zhao-xiang;GE Hai-yan(Ningbo Medical Treatment Center Lihuili Hospital, Ningbo , Zhejiang 315020, China)
出处
《中华医院感染学杂志》
CAS
CSCD
北大核心
2018年第12期1761-1767,共7页
Chinese Journal of Nosocomiology
基金
国家自然科学基金资助项目(81401819)
