超声靶向微泡破坏增强万古霉素活性治疗生物膜感染的实验研究

Enhancement of vancomycin activity in biofilm using ultrasound-targeted microbubble destruction

目的探讨超声靶向微泡破坏（UTMD）增强万古霉素活性治疗生物膜感染的效果。方法应用超声靶向微泡分组处理RP62A生物膜，结晶紫染色后OD570半定量检测，肉眼、光镜及激光共聚焦扫描显微镜观察生物膜的形态与细菌存活情况，菌落形成单位计数进一步对其内存活细菌进行定量检测。结果各超声或超声＋微泡组的生物膜可见许多微孔，其中超声＋微泡组和万古霉素＋超声组生物膜微孔显著较大，OD570半定量检测表明超声＋微泡组和万古霉素＋超声＋微泡组生物膜A。值最低（P〈0．01）。共聚焦激光扫描显微镜观察证实了生物膜微孔的存在，万古霉素＋超声＋微泡组较其他各组有更多的死菌（P〈0．01）。菌落形成单位计数进一步证实了上述结果。结论UTMD可有效提高抗生素活性，杀灭表皮葡萄球菌生物膜内细菌。

Objective To investigated whether ultrasound （US）-targeted microhubble （MB） destruction （UTMD） can enhance antibiotic activity. Methods Twenty-four hours biofilms of S. epidermidis RP62A were treated with different parameters in 6 groups. After the treatments, the absorbance values （A570） of biofilms stained with the crystal violet were measured to assess the density of biofilms. The biofilms were observed under macroscopy and light microscopy, and the morphology of biofilms were also examined and analyzed by eonfocal laser-scanning microscopy （CLSM）. The viable log10CFU among biofilms in different groups were compared. Results Many micropores were found in the biofilms treated with US and/or MB group. Even bigger micropores could be found in the hiofilms of US ＋ MB group and vancomycin＋ US ＋ MB group, with even smaller A570 values （P （0.01）. The CLSM examination confirmed the existence of the micropores and showed that the highest proportions of dead ceils were found in the vancomycin ＋ MB ＋ US group, and the results were confirmed further by the experiments of viable logl0CFU counts of biofilms. Conclusions UTMD might have a great potential in increasing antibiotic activity and reducing viable bacteria in biofilm.