RESUMO
The virulence of Paracoccidioides brasiliensis strains and the induction of the dimorphic process of the fungus were investigated. The strains were kept under mineral oil for different periods of time, except for one that was successively subcultured on agar slants. Four strains with transitional morphology at room temperature were avirulent to experimental animals. Two strains with typical morphology at 36 degrees C, one of them preserved under mineral oil for 16 years and the other maintained by successive subcultures for 10 years, were virulent to mice. These strains caused macro- and microscopic lesions in various organs, with enlargement of the spleen and heart. An attempt to induce the dimorphic process with fetal calf serum (FCS) in P.brasiliensis strains with transitional morphology failed. FCS was probably unable to stimulate the synthesis of Y cell wall alpha-1,3-glucan. The results demonstrate that keeping strains under mineral oil for a long period of time may have altered the enzymatic activities of the proteinases and other virulence factors that participate in the transition process and in pathogenesis.
Assuntos
Paracoccidioides/fisiologia , Paracoccidioides/patogenicidade , Paracoccidioidomicose/microbiologia , Animais , Bovinos , Meios de Cultura , Modelos Animais de Doenças , Sangue Fetal , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óleo Mineral , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioidomicose/patologia , Paracoccidioidomicose/fisiopatologia , Preservação Biológica , VirulênciaRESUMO
Malondialdehydemia (MDA), measurements of heart and liver tissue damage (TDU), plasma activity of heart alpha-hydroxybutyrate dehydrogenase (LDH1) and liver lactate dehydrogenase (LDH5) were determined in non-infected mice and in mice infected with 10(5) T. cruzi, Y strain, bloodstream trypomastigotes. All the parameters measured were increased (P less than 0.01) in infected mice 8 days after intraperitoneal inoculation. The results indicate that plasma MDA levels can serve as a useful indicator of the systemic tissue injury found in Chagas' disease.
Assuntos
Doença de Chagas/sangue , Fígado/enzimologia , Malonatos/sangue , Malondialdeído/sangue , Miocárdio/enzimologia , Animais , Membrana Celular/enzimologia , Hidroxibutirato Desidrogenase/sangue , Isoenzimas/sangue , L-Lactato Desidrogenase/sangue , Masculino , CamundongosRESUMO
Malondialdehydemia (MDA),, measurements of heart and liver tissue damage (TDU), plasma activity of heart alfa - hydroxybutyrate dehydrogenase (LDH1) and liver lactate dehydrogenase (LDH5) were determined in non-infected mice and in mice infected with 10*5 T. cruzi, Y strain, bloodstream trypomastigotes. All the parameters measured were increased (P < 0,01) in infected mice 8 days after intraperitoneal inoculation. The results indicate that plasma MDA levels can serve as a useful indicator of the systemic tissue injury found in chagas' disease
Assuntos
Camundongos , Animais , Masculino , Doença de Chagas/sangue , Fígado/enzimologia , Malondialdeído/sangue , Miocárdio/enzimologia , Malondialdeído/sangue , Cardiomiopatia Chagásica/sangue , Trypanosoma cruzi/patogenicidadeRESUMO
Evolution of the acute phase of experimetnal Chagas' disease was correlated with tissue damage and plasma levels of malondialdehyde. heart lesions were quantified by the Tissue Damage Unit (TDU) and malondialdehydemia (MDA) by the colorimetric determination of malondialdehyde. the binary correlations were: C(X,Y) =0.965 (P < 0.001); C(y,Z) =0.784 (P < 0.01); and C(X,Z) =0.824 (P < 0.01), where X = days of infection, Y = TDU means and Z = MDA means. These results show a positive correlation between the duration of the acute phase of experimental Cchagas' disease and TDU, and between the durtion and MDA. The methods for measuring tissue damage and MDA are shown to be simple and adequate for monitoring tissue aggression in the protozoosis studied
