RESUMO
In experimentally infected laboratory-bred white rats, Cryptosporidium infection rate was higher among immunosuppressed (75%) than immunocompetent ones (37.5%) with statistically insignificant difference. Cryptosporidiosis was found to be a fatal disease especially in immunosuppressed rats (50%). There was also marked flourishing of the infection as revealed by high intensity of infection in immunosuppressed than the immunocompetent rats (363 and 82.7 oocysts/pellet respectively). In spite of the severe disease, cyclophosphamide appeared to have no effect on the prepatent period. In both immunosuppressed and immunocompetent infected rats, there was a decrease in the total leucocytic count with marked lymphocytopaenia. This indicates decreased resistance to infection, thus higher oocyst counts in the pellets.
Assuntos
Criptosporidiose/imunologia , Animais , Criptosporidiose/sangue , Tolerância Imunológica , Contagem de Leucócitos , RatosRESUMO
By scanning electron microscopy (SEM), T. vaginalis surface appeared pleated with crater-like depressions. All the flagella appeared to start off in a single bundle from a shallow depression with a prominent rim. The side carrying the undulating membrane is extensively ruffled having a mulberry-like appearance to which flocculent material was frequently adherent. T. vaginalis nutrition appeared to proceed through pseudopodia-like extensions and phagocytosis by a constant deep invagination at the anterior pole which seems to be a cytostome. The mulberry-like surface may serve adhesion of T. vaginalis to the host cells and probably increases the surface area for exchange of nutrients, metabolites and parasite-derived factors.