Navegando por Autor "Cruz, Ruth Elizabeth"
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Item Effects of specific treatment on parasitological and histopathological parameters in mice infected with different Trypanosoma cruzi clonal genotypes.(2004) Toledo, Max Jean de Ornelas; Bahia, Maria Terezinha; Veloso, Vanja Maria; Carneiro, Cláudia Martins; Coelho, George Luiz Lins Machado; Alves, Cíntia Fontes; Martins, Helen Rodrigues; Cruz, Ruth Elizabeth; Tafuri, Washington Luiz; Lana, Marta deThe goal of this study was to verify the effect of specific treatment on parasitological and histopathological parameters in mice experimentally infected with different Trypanosoma cruzi clonal genotypes. Twenty cloned stocks were selected, representative of the whole phylogenetic diversity of the protozoan and belonging to the clonal genotypes 19 and 20 (T. cruzi I) and 39 and 32 (T. cruzi II). The stocks were inoculated in 40 BALB/c mice divided into four groups: (i) treated with benznidazole, (ii) treated with itraconazole and (iii and iv) untreated control groups (NT) for each drug, respectively. Seven parameters related to parasitaemia curves and histopathological lesions were analysed. Four during the acute phase (AP) and three during both the AP and chronic phase (CP) of infection. Statistical comparison between benznidazole-treated and NT groups for the biological parameters showed significant differences for all genotypes. Benznidazole treatment led to lower patent period, maximum of parasitaemia, day of maximum parasitaemia and area under the parasitaemia curve for all genotypes analysed. Percentage of positive haemoculture during AP and CP was lower for genotypes 19 and 32. Tissue parasitism (TP) and inflammatory process (IP) during AP were lower for genotypes 19 and 32, respectively. In general, itraconazole treatment induced a smaller reduction in these same parameters between treated and NT animals in relation to benznidazole treatment. Our results indicate that phylogenetic divergence among T. cruzi clonal genotypes must be taken in account in chemotherapy and studies dealing with all aspects of the parasite and the disease.Item Further genetic characterization of the two Trypanosoma cruzi Berenice strains (Be-62 and Be-78) isolated from the first human case of Chagas disease (Chagas, 1909).(2006) Cruz, Ruth Elizabeth; Macedo, Andréa Mara; Barnabé, Christian; Freitas, Jorge Marcelo de; Chiari, Egler; Veloso, Vanja Maria; Carneiro, Cláudia Martins; Bahia, Maria Terezinha; Tafuri, Washington Luiz; Lana, Marta deWe describe here an extension of a previous genetic characterization of Trypanosoma cruzi strains (Be-62 and Be-78) isolated from the patient Berenice, the first human case of Chagas disease [Chagas, C., 1909. Nova Tripanom´ıase humana. Estudos sobre morfologia e o ciclo evolutivo do Schizotrypanum cruzi, n. gen., n. sp., agente etiol´ojico da nova entidade morbida do homem. Mem. Inst. Oswaldo Cruz 1, 159–218]. We wanted to verify the composition of T. cruzi populations originated from these two isolates. In the present work, 22 enzymatic loci (MLEE), nine RAPD primers and 7 microsatellite loci were analyzed. Clones from both strains were also characterized to verify whether these strains are mono or polyclonal. Be-62 and Be-78 strains were different in 3 out of 22 enzymatic systems, in 3 out of 9 RAPD primers tested and in all microsatellite loci investigated. However, our data suggests that both strains are phylogenetically closely related, belonging to genetic group 32 from Tibayrenc and Ayala [Tibayrenc, M., Ayala, F.J., 1988. Isoenzime variability in Trypanosoma cruzi, the agent of Chagas’ disease: genetical, taxonomical, and epidemiological significance. Evolution 42, 277–292], equivalent to zymodeme 2 and T. cruzi II major lineage which, in Brazil, comprises parasites from the domestic cycle of the disease. Microsatellite analyses showed differences betweenthe parental strains but suggested that both populations are monoclonal since each strain and their respective clones showed the same amplification products.