【摘要】 目的研究巯乙磺酸钠(Mesna)对铜绿假单胞菌生物被膜(BF)形成的影响,以及对成熟铜绿假单胞菌BF的作用。方法微量稀释法检测Mesna对铜绿假单胞菌PAO1的最低抑菌浓度;建立铜绿假单胞菌BF体外模型,扫描电镜(SEM)观察Mesna对铜绿假单胞菌BF形成的作用;经Mesna作用成熟的铜绿假单胞菌BF后,平板计数法检测BF内活菌数,激光共聚焦显微镜(CLSM)观察Mesna对铜绿假单胞菌BF空间结构的影响并结合BF图像结构分析软件(ISA)定量分析BF结构参数。结果 Mesna对PAO1的MIC为10mg/ml;铜绿假单胞菌BF形成过程中,Mesna能减少BF中基质样物质以及被膜的厚度;与生理盐水对照组(7.45±0.10)比较,Mesna能使成熟铜绿假单胞菌BF中的活菌数减少(P<0.05),高浓度组(5.84±0.24)较低浓度组(4.06±0.12)更明显(P<0.05);CLSM图像显示,经Mesna作用后的BF厚度逐渐减少,密度逐渐稀疏;ISA软件定量分析显示,Mesna作用后,BF厚度、平均扩散距离(ADD)和结构熵(TE)均较生理盐水对照组减少(P<0.05),区域孔率(AP)增加(P<0.05),高浓度组较低浓度组更明显(P<0.05)。结论 Mesna能够抑制铜绿假单胞菌BF形成,破坏成熟铜绿假单胞菌BF形态结构。更多还原

【Abstract】 OBJECTIVE To investigate the effect of mesna on the formation of Pseudomonas aeruginosa biofilm,and study the effect of mesna on P.aeruginosa biofilm.METHODS The broth microdilution method was performed to determine the minimal inhibitory concentration of mesna to PAO1,then a biofilm model of Pseudomonas aeruginosa in vitro was established,the appearance of biofilm was detected by scanning electron microscope(SEM) to assess the effect of mesna on the formation of P.aeruginosa biofilm;the bacteria colony counts in biofilm was measured by agar plate after the biofilm was treated by mesna,biofilm structure was observed under confocal laser scanning microscope(CLSM),and the parameters of biofilm structure were analyzed through pictures from CLSM with image structure analyzer(ISA)software.RESULTS The MIC value against PAO1 was 10mg/mL for mesna.In the process of Pseudomonas aeruginosa biofilm formation,scanning electron microscope showed that the mucoid materials among bacteria was significantly reduced and the thickness of biofilm was decreased in mesna group.In comparison with normal saline group,viable counts in biofilms in the mesna treatment group were less than those in the saline group,and the high-dose group(4.06±0.12) had less positive effect than did the low-dose group(5.84±0.24)(P<0.05).Confocal laser scanning microscope showed that the biofilm was thinner and more scattered than the saline control group.The results of ISA showed that with the treatment of mesna,biofilm was decreased in thickness,average diffusion distance(ADD) and textual entropy(TE) in comparison with the saline control group(P<0.05),however areal porosity(AP) was increased(P<0.05),and the high-doses group was more significant than the low-doses group(P<0.05).CONCLUSION Mesna can inhibit the formation of P.aeruginosa biofilm and disrupt the structure of P.aeruginosa biofilm.更多还原