Department of Parasitology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, China.
Parasitology. 2012 Feb;139(2):244-7. doi: 10.1017/S0031182011001818. Epub 2011 Oct 24.
A traditional assumption is that schistosome cercariae lose their tails at the onset of penetration. It has, however, recently been demonstrated that, for Schistosoma mansoni, cercarial tails were not invariably being shed as penetration took place and a high proportion of tails entered human skin under experimental conditions. This phenomenon was termed delayed tail loss (DTL). In this paper, we report that DTL also happens with S. japonicum cercariae during penetration of mouse skin. It occurred at all cercarial densities tested, from as few as 10 cercariae/2·25 cm(2) of mouse skin up to 200 cercariae. Furthermore, it was demonstrated that there was a density-dependent increase in DTL as cercarial densities increased. No such density-dependent enhancement was shown for percentage attachment over the same cercarial density range.
传统观点认为，曼氏血吸虫尾蚴在开始穿透时会失去尾巴。然而，最近的研究表明，对于曼氏血吸虫尾蚴来说，在穿透过程中并非总是会脱落尾巴，而且在实验条件下，很大比例的尾巴会进入人体皮肤。这种现象被称为延迟尾脱落（DTL）。在本文中，我们报告说，在日本血吸虫尾蚴穿透小鼠皮肤时，也会发生 DTL。它发生在所有测试的尾蚴密度下，从每 2.25 平方厘米小鼠皮肤低至 10 条尾蚴到高达 200 条尾蚴。此外，研究表明，随着尾蚴密度的增加，DTL 呈密度依赖性增加。在相同的尾蚴密度范围内，附着百分比没有显示出这种密度依赖性增强。
