Entoepidemiology of Chagas disease in northwest Sao Paulo and cytogenetic analysis of its main vector, Triatoma sordida (Hemiptera: Triatominae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genetic Variability and Geographical Diversity of the Main Chagas' Disease Vector Panstrongylus megistus (Hemiptera: Triatominae) in Brazil Based on Ribosomal DNA Intergenic Sequences

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pharmacokinetics of Hydroxymethylnitrofurazone, a Promising New Prodrug for Chagas' Disease Treatment

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Entoepidemiology of Chagas disease in the Western region of the State of Sao Paulo from 2004 to 2008, and cytogenetic analysis in Rhodnius neglectus (Hemiptera, Triatominae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

De novo transcriptome assembly for a non-model species, the blood-sucking bug Triatoma brasiliensis, a vector of Chagas disease

High throughput sequencing (HTS) provides new research opportunities for work on non-model organisms, such as differential expression studies between populations exposed to different environmental conditions. However, such transcriptomic studies first require the production of a reference assembly. The choice of sampling procedure, sequencing strategy and assembly workflow is crucial. To develop a reliable reference transcriptome for Triatoma brasiliensis, the major Chagas disease vector in Northeastern Brazil, different de novo assembly protocols were generated using various datasets and software. Both 454 and Illumina sequencing technologies were applied on RNA extracted from antennae and mouthparts from single or pooled individuals. The 454 library yielded 278 Mb. Fifteen Illumina libraries were constructed and yielded nearly 360 million RNA-seq single reads and 46 million RNA-seq paired-end reads for nearly 45 Gb. For the 454 reads, we used three assemblers, Newbler, CAP3 and/or MIRA and for the Illumina reads, the Trinity assembler. Ten assembly workflows were compared using these programs separately or in combination. To compare the assemblies obtained, quantitative and qualitative criteria were used, including contig length, N50, contig number and the percentage of chimeric contigs. Completeness of the assemblies was estimated using the CEGMA pipeline. The best assembly (57,657 contigs, completeness of 80 %, < 1 % chimeric contigs) was a hybrid assembly leading to recommend the use of (1) a single individual with large representation of biological tissues, (2) merging both long reads and short paired-end Illumina reads, (3) several assemblers in order to combine the specific advantages of each.

Characterization of Trypanosoma cruzi Sirtuins as Possible Drug Targets for Chagas Disease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular identification of food sources in triatomines in the Brazilian northeast: roles of goats and rodents in Chagas disease epidemiology

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Study on Chagas disease occurrence in the municipality of Monte Negro, State of Rondônia, Brazilian Amazon

Introduction: Studies on Chagas disease deal with the perspective of its occurrence in the Amazon region, which is directly correlated to the population growth and the spread of the bug biotope. The state of Rondônia has an immense source of vectors (Triatomine) and reservoirs of Trypanosoma cruzi. Environmental changes brought forth by the deforestation in the region may cause vector behavior changes and bring these vectors to a closer contact with humans, increasing the probability of vector infection. Methods: This study was carried out to check the occurrence of Chagas disease in the municipality of Monte Negro, Rondônia, Brazil, based on a random sampling of the farms and people wherein blood collection from the population and capturing triatomines were done. The blood samples were submitted to serologic tests to detect antibodies of the IgG class against T. cruzi. The triatomines that were collected had their digestive tract checked for the presence of trypanosomatidae with morphology resembling that of the T. cruzi. Results: The population examined was mostly from other states. From the 322 bugs examined on the microscope, 50% showed parasites with morphology compatible with T. cruzi. From the serology of 344 random samples of human blood, 1.2% was found positive, 6% showed inconclusive results, and 92.8% were negative. Conclusions: Monte Negro shows low prevalence of human infection by T. cruzi and none active vector transmission; however, preventive and surveying measures, which are not performed until now, shall be taken due to the abundance of vectors infected by trypanosomatidae.

Impact of chagas disease in human evolution:the challenges continue

Chagas disease affects 8 to 10 million people worldwide and, although most of them live in Latin America, there has been an increase in cases occurring in countries of Europe and North America although most of them live in Latin America. This study aims to describe the epidemiological situation in the present as well as government and research centers actions, particularly the study group of Chagas disease of the School of Medicine of Botucatu (FMB/UNESP)/Brazil.

Indeterminate form of chagas disease and metabolic syndrome: a dangerous combination

Chagas’ disease (CD) has been a major concern in public health in Latin America countries and in Brazil there are about 3 million people suffering from this disease. With the social and economic changes which have been occurring in the last 6 decades in the country, there have been a lot of changes in the population life style with severe metabolic consequences, especially for those with Chagas' disease. The objective of this study was to evaluate the prevalence of metabolic syndrome in individuals with the indeterminate form of CD. A total of 74 individuals, mean age of 55.6 years, participated in the study. Anthropometric and biochemical evaluations were performed. Overweight/obesity was found in 86.5 % of individuals, increased waist circumference in 72.5%, and 67% had more than 30% of fat mass. Hyperglycemia and dyslipidemia were observed in 24.3% and 75.7% of patients, respectively. Metabolic syndrome was diagnosed in 48.2% of patients. The family history revealed high prevalence of cardiovascular diseases (80.3%), systemic arterial hypertension (57.1%) and diabetes mellitus (42.8%). A total of 90% of patients were overweight/obese, and it is well known that increased adipose tissue, specially visceral adipose tissue is highly associated with dyslipidemia and cardiovascular diseases, as well as imbalance in production of proinflammatory and antiinflammatory cytokines produced by that tissue. Adipocytes are also known as a reservoir for Trypanosoma cruzi, favoring an increase in parasite load and a possible reacutization of the disease. Therefore, the study individuals are at high risk of developing cardiovascular diseases as well as further symptomatic form of the Chagas' disease, mainlychagastic cardiopathy.

Miocardite chagásica em caninos no Estado do Rio Grande do Sul

Neste trabalho, são relatados dois casos de morte súbita por doença de Chagas aguda em caninos da zona rural de Porto Alegre, Rio Grande do Sul, Brasil. Os cães, um macho Pit Bull com nove meses (canino 1) e uma fêmea Labrador Retriever com dois anos (canino 2), morreram em janeiro de 2005 e maio de 2008, respectivamente. As necropsias revelaram aumento cardíaco em ambos os casos. O coração do canino 2 apresentou formato globoso com múltiplas áreas pálidas na musculatura cardíaca, mais evidentes no ventrículo direito e câmaras cardíacas dilatadas, principalmente as da direita. Ao exame histológico, ambos os casos apresentaram alterações semelhantes caracterizadas por infiltrado inflamatório difuso não-purulento acentuado, predominantemente linfocitário intersticial. Nas fibras miocárdicas, havia grande número de pseudocistos, repletos de formas amastigotas do Trypanosoma cruzi. Ao teste sorológico TESA-blot, amostra do canino 2 foi positiva para anticorpos IgM e IgG anti-T.cruzi, achado característico da fase aguda da miocardite chagásica. Os resultados indicam que a doença de Chagas deve ser investigada em casos de morte súbita em cães na região Sul do Brasil e que a espécie pode servir como reservatório e sentinela da doença em humanos.

Doença de Chagas aguda pós-transfusional sem miocardite

Trata-se de paciente do sexo feminino, com 59 anos de idade, procedente de Itaporanga (SP), diabética e nefropata crônica, internada em virtude de surtos de pielonefnte e insuficiência renal aguda. Dentre outras medidas terapêuticas, recebeu transfusão de sangue. Cerca de dois dias após a última transfusão (sangue oriundo de doador, posteriormente identificado como chagásico) encontraram-se formas tripomastigotas de Trypanosoma cruzi em lâmina preparada para execução de hemograma. Iniciou-se tratamento com Benzonidazol. A paciente cursou para, pleuropneumonia e de secreção purulenta cirúrgica isolou-se Klebsiella spp. A septicemia conduziu a paciente ao êxito letal. Nenhuma lesão tecidual foi observada no miocárdio, no sistema nervoso central, adrenal ou nos demais órgãos examinados.

Voltammetric behavior of nitrofurazone and its hydroxymethyl prodrug with potential anti-chagas activity

Chagas' disease is a serious health problem for Latin America. The situation is worsened by the lack of efficient chemotherapy. The two available commercial drugs, benznidazole and nifurtimox, are more effective in the acute phase of the disease. Nitrofurazone is active against Trypanosoma cruzi, however its high toxicity precludes its current use in parasitosis. Hydroxymethylnitrofurazone is a prodrug of nitrofurazone. It is more active against Trypanosoma cruzi than nitrofurazone, besides being less toxic. This work shows the voltammetric behavior of nitrofurazone and a comparison with those of metronidazole and chloramphenicol using cyclic, linear sweep and differential pulse voltammetries. For these drugs also the prediction of the diffusion coefficients using Wilke-Chang equation was performed. The reduction of nitrofurazone is pH-dependent and in acidic medium the hydroxylamine derivative, involving four electrons, is the principal product formed. In aqueous-alkaline medium and with a glassy carbon electrode pre-treatment the reduction of nitrofurazone occurs in two steps, the first involving one electron to form the nitro-radical anion and the second corresponding to the hydroxylamine derivative formation. Hydroxymethylnitrofurazone presented the same voltammetric behavior and electroactivity, indicating that the molecular modification performed in nitrofurazone did not change its capacity to be reduced. A brief discussion regarding the differences in biological activity between the two compounds is also presented. ©2005 Sociedade Brasileira de Química.

Isolamento e caracterização de cepas de Trypanosoma cruzi Chagas,1909 (Kinetoplastida, Trypanosomatidae) a partir de triatomíneos silvestres do Estado do Rio Grande do Sul

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR