Caracterização molecular de isolados de Trypanosoma cruziobtidos de mulheres durante a fase crônica da doença de Chagas
Abstract (Summary)Chagas disease is a zoonotic disease caused by a protozoan plaguedcalled Trypanosoma cruzi, it is a particular problem in Latin America, where it isestimated that 12 to 14 million people are infected. The populations ofTrypanosoma cruzi can be divided into two major groups, the Trypanossomacruzi I (TCI) and Trypanossoma cruzi II (TCII), the last being moreheterogeneous and divided into five subgroups TCIIa, TCIIb, TCIIc, TCIId andTCIIe However, little is known of epidemiological and clinical implications ofthese ratings. The frequency of vertical transmission of Chagas disease canvary from 1.6 to 18.5% in accordance with the region and the methodology usedin the studies. The aim of this study was to genetic characterization of 30isolates of T. cruzi through the blood of patients with Chagas disease in thechronic phase, pregnant and not pregnant. The genetic characterization wasperformed with three different markers that amplified regions of the 18S and24S amp;#945; DNA ribosomal and mini-exon of the gene that allows classify the groupsand subgroups of the parasite and the analysis of genetic variability amongisolates of T. cruzi was performed the characterization of the variable region ofminicicles of kDNA through the technique of Low-Stringency Single SpecificPrimer-PCR (LSSP-PCR). The 30 patients studied 75% (25/30) were womenand 25% (5 / 30) not pregnant. The patients are the four different Brazilianregions being the States of Bahia 53.3% (16/30), Goiás 40.0% (12/30), Paraíba3.3% (1 / 30) and the Federal District 3, 3% (1 / 30). The analysis of rDNAallowed show the TCII in 100% of the isolated populations in the regionsstudied, where the subgroup TCIIb/e has been detected in (96.66%) and TCIIdin (3.33%) the latter is a sample of the group Control of the State of Bahia. Thegenetic variability between the 30 samples was 24.08 ± 14.4% share of bandsamong pairs. There was no difference between the share of bands patients ofBahia and Goiás, where the value of significance was less than 5%. There wasno difference between the percentages of bands showed in analyses by age ofthe patients, gestational age and in the analysis of the groups of pregnant andnot pregnant. In reviewing more than one tube of blood per patient comingevidenced profiles of signatures genomic complex and heterogeneous with62.5% of bands shared less than 77% and only 37.5% had rates higher than83% of bands sharing among samples. Suggesting so our isolates showed agreat genetic variability.
Advisor:Ana Maria de Castro
Source Type:Master's Thesis
Date of Publication:02/29/2008