摘要
目的 探讨低强脉冲超声联合3.5g/L聚维酮碘溶液对耐甲氧西林金黄色葡萄球菌(MRSA)生物膜的体外抗菌活性.方法 在玻璃爬片或共聚焦皿表面建立MRSA未成熟(培养24 h)及成熟(培养72 h)生物膜,根据不同干预方法随机分成4组(n=9):对照组将玻璃爬片或共聚焦皿置入500 mL生理盐水中3 min,PI组将玻璃爬片或共聚焦皿置入500 mL 3.5 g/L聚维酮碘溶液中3 min,LIPUS组将玻璃爬片或共聚焦皿置人500 mL生理盐水中同时联合低强脉冲超声(LIPUS)干预3 min,LIPUS & PI组将玻璃爬片或共聚焦皿置入500 mL3.5 g/L聚维酮碘溶液中同时联合LIPUS干预3 min.干预后进行共聚焦显微镜(CLSM)、扫描电镜(SEM)观察,比较4组MRSA生物膜的结构、形态、生物膜内细菌存活状态及活菌计数等.结果 在培养24、72h生物膜中,CLSM及SEM观察到LIPUS组及LIPUS & PI组生物膜稀疏,且LIPUS & PI组伴有大量死菌.在培养24 h生物膜中,对照组、PI组、LIPUS组及 LIPUS & PI 组的细菌菌落数分别为(1.21±0.45)× 106、(3.38±2.81)× 103、(1.82±0.37)× 103、(69.67±27.93)CFU/mL,除PI组与LIPUS组比较差异无统计学意义(P＞0.05)外,其余各组之间两两比较差异均有统计学意义(P＜0.05).在培养72 h生物膜中,对照组、PI组、LIPUS组及LIPUS &PI 组的细菌菌落数分别为(3.01±0.70)×106、(1.80±1.52)×105、(2.10±0.52)× 103、(68.67±19.55)CFU/mL,4组之间两两比较差异均有统计学意义(P＜0.05).结论 单独LIPUS或3.5 g/L聚维酮碘溶液在未成熟及成熟体外生物膜中作用3 min仅具有部分抗菌活性.LIPUS可以增强3.5 g/L聚维酮碘溶液在不同成熟度体外生物膜中的抗菌活性.
Abstract
Objective To explore the in vitro antibacterial effects of low-intensity pulsed ultrasound(LIPUS)combined with 3.5 g/L povidone iodine solution on the biofilm of methicillin-resistant staphylococcus aureus(MRSA).Methods Immature(cultured for 24 hours)and mature(cultured for 72 hours)MRSA biofilms were established on the surfaces of glass slides or confocal dishes.They were randomly divided into 4 groups(n=9)according to different intervention methods.In the control group,glass slides or confocal dishes were placed in 500 mL of physiological saline for 3 minutes;in the PI group,glass slides or confocal dishes were placed in 500 mL of 3.5 g/L povidone iodine solution for 3 minutes;in the LIPUS group,glass slides or confocal dishes were placed in 500 mL of physiological saline and simultaneously intervened with LIPUS for 3 minutes;in the LIPUS & PI group,glass slides or confocal dishes were placed into 500 mL of 3.5 g/L povi-done iodine solution and simultaneously intervened with LIPUS for 3 minutes.After intervention,confocal mi-croscopy(CLSM)and scanning electron microscopy(SEM)were used to observe and compare the structure,mor-phology,bacterial survival,and viable cell count of the MRSA biofilms among the 4 groups.Results On the MRSA biofilms cultured for 24 and 72 hours,CLSM and SEM observed sparse biofilms in the LIPUS group and LIPUS & PI group,and also a large number of dead bacteria in the LIPUS & PI group.On the MRSA biofilms cultured for 24 hours,the bacterial colony counts in the control group,PI group,LIPUS group,and LIPUS & PI group were(1.21±0.45)× 106 CFU/mL,(3.38±2.81)× 103 CFU/mL,(1.82±0.37)× 103 CFU/mL,and(69.67±27.93)CFU/mL,respectively.Except for the comparison between PI group and LIPUS group,which showed no statistically significant difference(P＞0.05),there were statistically signifi-cant differences between the other groups when compared pairwise(P＜0.05).On the MRSA biofilms cultured for 72 hours,the bacterial colony counts in the control group,PI group,LIPUS group,and LIPUS & PI group were(3.01±0.70)×106 CFU/mL,(1.80±1.52)× 105 CFU/mL,(2.10±0.52)× 103 CFU/mL,and(68.67±19.55)CFU/mL,respectively.There were statistically significant differences between the 4 groups when compared pairwise(P＜0.05).Conclusions Application of LIPUS or 3.5 g/L povidone iodine alone for 3 minutes on the immature or mature MRSA biofilms in vitro only leads to partial antibacterial activity.However,LIPUS can enhance the in vitro antibacterial effect of 3.5 g/L povidone iodine on the MRSA biofilms at different maturity levels.
基金项目
新疆维吾尔自治区科技计划重大专项课题(2022A03011)
新疆维吾尔自治区自然科学基金面上项目(2022D01C475)
NETL
NSTL
万方数据