INOCULATION EXPERIMENTAL-ANIMALS WITH PARACOCCIDIOIDES-BRASILIENSIS STRAINS - AN ATTEMPT TO REESTABLISH THE DIMORPHIC PROCESS AND VARIATIONIN PATHOGENICITY AS A FUNCTION OF TIME OF PRESERVATION UNDER MINERAL-OIL

In an attempt to reestablish the dimorphic process in strains of Parac occidioides brasiliensis in the transition phase (Y reversible arrow M ) and to reisolate them, five strains in the transitional phase due to the long time of preservation under mineral oil and two strains in th e yeast-like phase were inoculated into male albino rats. The animals were then studied for the presence of paracoccidioidomycotic granuloma ta. Of the seven strains inoculated, five caused granulomatous nodules in several organs of the animals and only two of these five strains, which had been preserved for the shortest period of time (9 years) wer e reisolated in culture. Two strains were unable to provoke infection, with no lesions detected in any organ. It is assumed that the long pe riod of time during which the strains were left under oil favored the alteration of celt wall contents, leading to differences in pathogenic ity.