光动力对铜绿假单胞菌PAO1浮游菌与生物被膜的体外清除作用

发布时间：2018-06-03 16:45

本文选题：光动力疗法 + 铜绿假单胞菌　；参考：《中国激光医学杂志》2014年02期

【摘要】：目的分析新型光敏剂钌化合物(Ru complex)介导的光动力治疗(Photodynamic therapy,PDT)对铜绿假单胞菌PAO1浮游菌和生物被膜内细菌活性的影响,观察PDT对其生物被膜的清除作用。方法实验对象为细菌悬液和生物被膜模型,均分为四组。细菌悬液组的光敏剂浓度为0.1、0.25、1、2.5、10和25μM;生物被膜组的光敏剂浓度为1、2.5、10和25μM。(1)PDT组:加入不同浓度的光敏剂后,孵育时间30 min,采用激光照射,功率密度为40 mW/cm2,照射时间10 min。(2)单纯光敏剂组:光敏剂孵育时间30 min,不予激光照射。(3)单纯照光组:仅激光照射,功率密度40 mW/cm2,照射时间10 min。(4)空白对照组:不加入光敏剂,不予激光照射。用稀释平板法和MTT法分别测定各组处理后浮游菌存活率和生物被膜内细菌活性。生物被膜经过冲洗、固定、结晶紫染色后,用光镜观察其结构改变。结果在本实验浓度范围内,PDT杀伤铜绿假单胞菌的作用呈光敏剂浓度依赖性。以10和25μM Ru-PDT处理PAO1浮游菌和生物被膜均能够显著杀伤,浮游菌杀伤分别达到99.99%和99.9999%以上,生物被膜内菌的杀伤分别为60.1%和66.0%,进一步提高光敏剂浓度至50μM,光动力作用没有显著增强。单纯照光或光敏剂孵育对细菌存活无影响。光镜观察PDT处理组生物被膜发现其结构完整性遭到破坏,整体稀疏分散。结论 Ru-PDT在体外对铜绿假单胞菌浮游菌和生物被膜内细菌都具有很好的杀伤作用;浮游菌相比生物被膜内的细菌对PDT作用更加敏感。PDT不仅可以使生物被膜内细菌失去活性,还可以破坏其结构,具有清除作用。
[Abstract]:Objective to investigate the effects of photodynamic therapy (PDT) mediated by Ru complex, a new Guang Min agent, on the activity of phytoplankton bacteria and biofilm bacteria of Pseudomonas aeruginosa (PAO1), and to observe the scavenging effect of PDT on the biofilm of Pseudomonas aeruginosa (Pseudomonas aeruginosa). Methods the models of bacterial suspension and biofilm were divided into four groups. The concentration of Guang Min in the bacterial suspension group was 0.1a 0.25U 2.5U 10 and 25 渭 m, and the concentration of Guang Min in the biofilm group was 1g 2.5g 10 and 25 渭 M.(1)PDT: after the addition of different concentrations of Guang Min, the incubation time was 30 min, and the irradiation time was 30 min, and the concentration of Guang Min in the biofilm group was 30 min. Power density was 40 MW / cm ~ 2, irradiation time was 10 min 路min ~ (2) Guang Min group: Guang Min incubated for 30 min, no laser irradiation. 3) irradiation group: laser irradiation only, power density 40 MW / cm ~ (2), irradiation time 10 min 路min. 4) blank control group: no addition of Guang Min. No laser irradiation. The survival rate of phytoplankton and the activity of bacteria in biofilm were determined by dilution plate method and MTT method respectively. The biofilm was washed, fixed and stained with crystal violet. Results the killing effect of PDT on Pseudomonas aeruginosa was concentration dependent on Guang Min. When treated with 10 and 25 渭 M Ru-PDT, both PAO1 phytoplankton bacteria and biofilm could kill significantly, and the killing rate of phytoplankton bacteria was more than 99.99% and 99.9999%, respectively. The killing rate of biofilm bacteria was 60.1% and 66.0% respectively. The photodynamic effect was not significantly enhanced when the concentration of Guang Min was increased to 50 渭 m. The survival of bacteria was not affected by irradiation or Guang Min alone. Under light microscope, the biofilm of PDT treatment group was found to be damaged in structural integrity and sparse and dispersed as a whole. Conclusion Ru-PDT can kill Pseudomonas aeruginosa phytoplankton bacteria and biofilm bacteria in vitro, and that phytoplankton bacteria are more sensitive to PDT than biofilm bacteria. It can also destroy its structure and has the function of cleaning.
【作者单位】：解放军总医院激光医学科;
【基金】：国家自然科学基金(81171633) 北京市自然科学基金(4132079)
【分类号】：R378

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