RESUMO
An isolate of Trypanosoma cruzi obtained from P. megistus captured in the peridomicile area of a home in Santo Antonio do Jardim city in the State of Sao Paulo, denominated T. cruzi Mogi, was characterized biologically and molecularly. The RFLP analysis of the D7 divergent domain in the 24Sα rDNA and of the mini-exon positioned the T. cruzi isolate within the TcI group. Phylogenetic analysis performed with the trypanosomatid barcode confirmed that the isolate belongs to the TcI group, with high homology to the 3014 c1 T.cruzi strain. The biological characterization of the isolate in rats showed a prepatent period of about 8 days, low parasitemia and tropism for cardiac, skeletal and colonic muscles. In Swiss mice the T. cruzi Mogi isolate showed a prepatent period of about 22 days, intermittent parasitemia in some animals, and tropism for cardiac and colonic muscles. Despite the inherent difficulty of identifying correlations amongst the molecular and biological characteristics of different T. cruzi groups, the tropism for colonic muscle demonstrated by T. cruzi Mogi represented a peculiarity of this isolate within the TcI group.
Assuntos
Panstrongylus/parasitologia , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade , Estruturas Animais/parasitologia , Animais , Brasil , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Código de Barras de DNA Taxonômico , Impressões Digitais de DNA , DNA de Protozoário/genética , DNA Ribossômico/genética , Modelos Animais de Doenças , Masculino , Camundongos , Polimorfismo de Fragmento de Restrição , Ratos Wistar , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genéticaRESUMO
Triatoma infestans, the main vector of Chagas disease, has nearly been eliminated from Brazil. Nevertheless, other triatominae species are involved in the domiciliation process, including Triatoma rubrovaria in Rio Grande do Sul State (RS). Previous studies showed that 1.6% of the T. rubrovaria specimens collected at the rural district of Quaraí, RS, were naturally infected by Trypanosoma cruzi. In this study, five T. cruzi isolates obtained from infected triatomines were characterized molecularly and biologically. Genotyping of the T. cruzi isolates showed that they belong to lineage IIc of T. cruzi (TCIIc). Biological characterization showed miotropism and myositis during acute and chronic phases of infection, respectively. Virulence and mortality rates were variable among isolates. To our knowledge, this study corresponds to the first characterization of T. cruzi isolates from T. rubrovaria and the first description of TCIIc in the sylvatic cycle of T. cruzi from the southern region of Brazil.
Assuntos
Doença de Chagas/transmissão , Insetos Vetores/parasitologia , Triatoma/parasitologia , Trypanosoma cruzi/classificação , Animais , Brasil , Genótipo , Camundongos , Músculo Esquelético/parasitologia , Músculo Esquelético/patologia , Parasitemia , Filogenia , População Rural , Fatores de Tempo , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade , VirulênciaRESUMO
Os autores apresentam um caso raro de autopsia de adenocarcinoma gástrico com componente coriocarcinomatoso. A pesquisa de antígeno carcinoembriônico (CEA) e gonadotrofina coriônica (HCG) no tecido, pela técnica de imunoperoxidase, revelou CEA no elemento glandular do tumor e HCG no componente coriocarcinomatoso. Esses marcadores tumorais säo úteis tanto no esclarecimento diagnóstico de neoplasias indeferenciadas, quanto no seguimento de pacientes tratados cirurgicamente, com dosagens séricas. Esta é uma neoplasia de prognóstico extremamente reservado. Comenta-se, também, aspectos com relaçäo à histogênese desse tumor gástrico
