论文部分内容阅读
目的 建立一种快速简便测定蛋白酶活力的方法并研究不同来源的临床分离白念珠菌菌株的蛋白酶活力与其毒力的关系。方法 借助于白念在生物形态分型培养基上以３０℃孵育２ 天后形成特征性红褐色色素环为依据检测蛋白酶活力。选择３株蛋白酶活力不同的菌株进行小白鼠毒力试验，观察小白鼠死亡率及不同菌株在体内的生长率来探讨蛋白酶与毒力的关系。结果 从血液、脑脊液和尿液标本分离蛋白酶阳性的菌株检出率与粪便、阴道分泌物、口腔分泌物、皮屑和鼻咽分泌物分离菌株之间比较有显著性差异（Ｐ＜ ０．０５），而前者之间的比较无显著性（Ｐ＞ ０．０５）。动物试验表明蛋白酶活力越强的菌株，小白鼠平均生存时间越短（ｒ＝ ０．７４４７，Ｐ＜ ０．０１），菌株在体内的增殖速度越快，维持时间越长（ｒ＝ － ０．５８８０，Ｐ＜ ０．０５）。结论 不同来源的标本临床分离株蛋白酶活力有明显差别，活力的高低与其毒力有密切相关。该蛋白酶活力测定方法可用于体外直接指示白念毒力
Objective To establish a rapid and simple method for the determination of protease activity and to study the relationship between protease activity and virulence of clinically isolated C. albicans strains from different sources. Methods The activity of protease was detected on the basis of white pigment on the morphological typing medium and incubated at 30 ℃ for 2 days to form a characteristic reddish brown pigment ring. Three strains with different protease activities were selected to test the virulence of mice and to observe the mortality of mice and the growth rate of different strains in vivo. Results The detection rates of protease positive isolates from blood, cerebrospinal fluid and urine samples were significantly different from those of feces, vaginal secretions, oral secretions, dander and nasopharyngeal secretions (P <0.05 ), While there was no significant difference between the former (P> 0.05). Animal experiments showed that the stronger the protease activity of strains, the shorter the average survival time of mice (r = 0.7447, P <0.01), the faster the proliferation of the strain in vivo, the longer the maintenance time (r = - 0. 5880, P <0.05). Conclusion The protease activities of clinical isolates from different sources have obvious difference. The level of vitality is closely related to their virulence. The protease activity assay can be used to directly indicate virulence in vitro