两种地霉对甲板侵袭力的分析

Analysis on the Pathogenicity of the Two Kinds Geotrichum to Human Nails

目的通过建立真菌透甲模型,探讨林生地霉、白地霉在体外能否侵犯健康甲板。方法以红色毛癣菌作为阳性对照,制备透甲模型,分为林生地霉组、白地霉组和红色毛癣菌组,观察并记录各组透甲时间,采用统计学方法比较是否存在差异性。采用扫描电镜观察受侵甲板的微观变化。结果三株真菌的菌丝均能穿透甲板,其中林生地霉组的透甲时间为(15.07±3.28)d,白地霉组为(14.50±1.67)d,红色毛癣菌组为(6.76±1.72)d。林生地霉组和白地霉组的透甲时间均明显长于红色毛癣菌组,差异有统计学意义(P<0.05),林生地霉组和白地霉组的透甲时间差异无统计学意义(P>0.05)。扫描电镜观察到三种菌株均有菌丝从角化细胞缝隙及细胞中央穿过,相对于健康甲板,受侵甲板背侧面角化细胞"鱼鳞样"排列消失,边缘模糊,细胞间隙宽窄不等,腹侧面角化细胞未见明显变化。结论林生地霉和白地霉均能穿透甲板,但侵袭力较红色毛癣菌弱。

Objective The model of fungal penetrating to human nails was established to study if Geotrichum Silvicola, Geotrichum candidum and Trichophyton rubrum could damage the health human nail in vitro. Methods We divided the G. sivicola, the G. candidum and the T. rubrum into three groups respectively to establish the models. Then the passing time of three strains fungi was compared to study the pathogenicity. The change of the damaged nails was observed by the scanning electron microscope （SEM）. Results Three strains fungal all could penetrate human nails in vitro, the passing time of G. sivicola, G. candidum and T. rubrum was （ 15.07 ± 3.28 ） d, （ 14. 50 ± 1.67 ） d and （ 6. 76 ± 1.72） d respectively. The passing time of G. sivicola and G. candidum was longer than that of T. rubrum （ P 〈 0. 05 ）. There was no statistic difference between the time of G. sivicola and G. candidum （ P 〉 0. 05 ）. SEM showed that hyphae of 3 strains fungi all could penetrate keratinocytes of nails. Compared with the nail of negative control, the normal scale order of the invaded keratinocytes in dorsal surface of the nail was disappeared. The edge of ceils was changed to fuzzy and the width between cells was varied. Conclusion G. sivicola and G. candidum can penetrate the nail plate in vitro, but their pathogenicity is weaker than that of T. rubrum.