862 resultados para Doença de Chagas - genética molecular


Relevância:

100.00% 100.00%

Publicador:

Resumo:

We investigate the effects of augmented life expectancy and health improvements on human capital investment, labor supply and fertility decisions. Our main motivation is the prediction of human capital theory that a longer and healthier life encourages educational investment and female labor force participation, while discouraging fertility. To assess the magnitude of these effects, we explore a national campaign against Chagas disease in Brazil as an exogenous source of adult mortality decline and improvement in health conditions. We show that, relative to non-endemic areas, previously endemic regions saw higher increases in educational investment, measured by literacy, school attendance and years of schooling, following the campaign. Additionally, we find that labor force participation increased in high prevalence areas relative to low prevalence ones. Furthermore, we estimate a substantially higher effect on female labor force participation relative to male, suggesting that longevity gains and health improvements affected women's incentives to work, encouraging women to join the labor force. We do not find significant effects on fertility decisions.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Leishmania infantum and Trypanosoma cruzi are trypanosomatids of medical importance and are, respectively, the etiologic agents of visceral leishmaniasis (VL) and Chagas disease (CD) in Brazil. People infected with L. infantum or T. cruzi may develop asymptomatically, enabling the transmission of pathogens through blood transfusion and / or organs. The assessment of the infection by T. cruzi is included among the tests performed for screening blood donors in Brazil, however, there is no availability of tests for Leishmania. Serological tests for T. cruzi are very sensitive, but not specific, and may have cross-reactions with other microorganisms. Thus, the aim of this study was to determine the prevalence of Leishmania infection in blood donors and assess whether the serological test for T. cruzi detect L. infantum. Among the 300 blood samples from donors, discarded in 2011, 61 were T. cruzi positive, 203 were from donors with other infections and 36 were from handbags with low blood volume, but without infection. We also assessed 144 samples from donors without infections and able to donate blood, totaling 444 subjects. DNA was extracted from blood samples of all to perform quantitative PCR (qPCR) to detect Leishmania DNA. The buffy coat obtained from all samples was grown in Schneider medium supplemented and NNN. All samples were evaluated for the presence of anti-Leishmania antibody. The serological results indicate a percentage of 22% of Leishmania infection in blood samples obtained from discarded bags. A total of 60% of samples positive in ELISA for T. cruzi were negative by IFI, used as confirmatory test, ie 60% false positive for Chagas. Among these samples false positive for Chagas, 72% were positive by ELISA for Leishmania characterizing the occurrence of cross reaction between serologic assays. Of the 300 cultures performed, 18 grew parasites that were typed by qPCR and specific isoenzymes, found the species Leishmania infantum crops. Among the 18 cultures, 4 were purged from scholarships for low volume and all negative serology blood bank, thus demonstrating that there is a real risk of Leishmania transmission via transfusion. It is concluded that in an area endemic for leishmaniasis in Brazil, serological diagnosis performed to detect infection by T. cruzi among blood donors can identify infection by L. infantum and although cause false positive for Chagas, this cross-reactivity reduces the risk of Leishmania infection via blood transfusion, since tests are not applied specific detection of the parasite. In this way, there remains the need to discuss the implementation of a specific serological screening test for Leishmania in endemic countries such as Brazil

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Introdução: O dano miocárdico na doença de Chagas resulta tanto da ação parasitária quanto da resposta imune do hospedeiro humano. O mimetismo molecular entre proteínas do Trypanosoma cruzi e vários antígenos do hospedeiro tem sido amplamente descrito gerando células T CD8+ e anticorpos autorreativos. Entretanto, a geração dos autoanticorpos e seu papel na imunopatogenia da doença de Chagas ainda não têm sido elucidados, o que nos levou, neste trabalho, a avaliar a produção de imunoglobulina G total (IgGt) e seus isotipos anti-T. cruzi, proteínas cardíacas e sua possível associação com as diferentes formas clínicas da doença de Chagas. Métodos: A produção de IgGt e isotipos foi mensurada pelo método de ELISA no soro de pacientes com as formas clínicas indeterminada (IND, n=72), cardíaca (CARD, n=47) e digestiva/cardio-digestiva (DIG/CARD-DIG, n=12) da doença de Chagas, usando como antígenos as formas epimastigota e tripomastigota do T. cruzi e proteínas cardíacas humana (miosina e troponina T). As amostras de indivíduos não infectados saudáveis (CONT, n= 30) e pacientes com cardiomiopatia isquêmica (ISCH, n=15) foram usadas como controle. Os títulos de autoanticorpos foram correlacionados com parâmetros da função cardíaca obtidos por exames eletrocardiográficos, radiográficos e ecocardiográficos. Resultados: Neste estudo foram incluídos 131 indivíduos sem diferença significativa relativa à idade ou sexo. Destes, 55% foram classificados como IND, 35,9% CARD e 9,1% DIG/CARD-DIG. Os títulos de IgGt foram mais elevados em pacientes com as formas clínicas IND, CARD e DIG/CARD-DIG do que em indivíduos CONT e ISCH usando os antígenos as formas tripomastigotas e epimastigotas do T. cruzi e, proteínas cardíacas humanas. Os pacientes com formas clínicas CARD e DIG/CARD-DIG mostraram a produção mais elevada de IgG total dirigida contra antígenos de tripomastigota e epimastigota do que os IND. Os grupos de pacientes IND e CARD apresentaram uma similar produção de IgG total específica direcionada à miosina e troponina T, e mais elevada do que em indivíduos CONT e ISCH. Há uma correlação negativa entre a produção de anticorpos anti-proteínas cardíacas com a fração de ejeção do ventrículo esquerdo (FEVE) em pacientes chagásicos crônicos. Os pacientes foram agrupados em baixo e alto produtores de autoanticorpos e comparados com a fração de ejeção demonstrando que em pacientes alto produtores de anti-troponina T (p=0.042) e miosina (p=0.013) a FEVE foi mais baixa do que os baixo produtores. A maioria dos pacientes chagásicos produz simultaneamente autoanticorpos direcionados à ambas proteínas cardíacas (r=0.9508, p=0.0001). Conclusões: Estes resultados indicam que os autoanticorpos anti- troponina T e miosina cardíaca parecem induzir redução FEVE e deve ser associado com o desenvolvimento de cardiomiopatia chagásica

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The benznidazole (BNZ) is the only alternative for Chagas disease treatment in Brazil. This drug has low solubility, which restricts its dissolution rate. Thus, the present work aimed to study the BNZ interactions in binary systems with beta cyclodextrin (β-CD) and hydroxypropyl-beta cyclodextrin (HP-β-CD), in order to increase the apparent aqueous solubility of drug. The influence of seven hydrophilic polymers, triethanolamine (TEA) and 1-methyl-2- pyrrolidone (NMP) in benznidazole apparent aqueous solubility, as well as the formation of inclusion complexes was also investigated. The interactions in solution were predicted and investigated using phase solubility diagram methodology, nuclear magnetic resonance of protons (RMN) and molecular modeling. Complexes were obtained in solid phase by spray drying and physicochemical characterization included the UV-Vis spectrophotometric spectroscopy in the infrared region, scanning electron microscopy, X-ray diffraction and dissolution drug test from the different systems. The increment on apparent aqueous solubility of drug was achieved with a linear type (AL) in presence of both cyclodextrins at different pH values. The hydrophilic polymers and 1-methyl-2-pyrrolidone contributes to the formation of inclusion complexes, while the triethanolamine decreased the complex stability constant (Kc). The log-linear model applied for solubility diagrams revealed that both triethanolamine and 1-methyl-2-pyrrolidone showed an action cosolvent (both solvents) and complexing (1-methyl-2-pyrrolidone). The best results were obtained with complexes involving 1-methyl-2-pyrrolidone and hydroxypropylbeta- cyclodextrin, with an increased of benznidazole solubility in 27.9 and 9.4 times, respectively. The complexes effectiveness was proven by dissolution tests, in which the ternary complexes and physical mixtures involving 1-methyl- 2-pyrrolidone and both cyclodextrins investigated showed better results, showing the potential use as novel pharmaceutical ingredient, that leads to increased benznidazole bioavailability

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A uricemia foi estudada em uma amostra de 192 indivíduos de uma região altamente endêmica para a doença de Chagas (Bambuí, Estado de Minas Gerais, Brasil). A amostra continha 50 indivíduos sorologicamente negativos (controles) e os positivos foram classificados na base da presença de alterações eletrocardiográficas (63), esvaziamento esofagiano alterado (16), ou ausência de sinais ou sintomas da doença (76). Somente os indivíduos com a forma digestiva da doença de Chagas crônico mostraram hiperuricemia, quando comparados com controles adequados. Dados familiares sugerem que a hiperuricemia é um efeito da patologia digestiva em vez de causa, uma vez que os irmãos não afetados dos pacientes com megaesôfago não apresentaram níveis elevados de ácido úrico sérico. São postulados alguns mecanismos possivelmente responsáveis pelos achados.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Desde a década de 1970 não se notificavam casos autóctones de doença de Chagas aguda em São Paulo. em março de 2006 a Vigilância Epidemiológica registrou óbito por doença de Chagas aguda, em Itaporanga, de paciente de seis anos de idade. Exame histopatológico post mortem realizado no Hospital das Clínicas da Faculdade de Medicina de Botucatu confirmou o diagnóstico. Consultamos prontuários de hospitais e entrevistamos profissionais de saúde envolvidos além de familiares do paciente. Descrevemos medidas adotadas in loco para identificar a via de transmissão, reservatórios e vetores. Discutimos as possíveis fontes de infecção. Na região não foram identificados outros casos humanos, vetores ou reservatórios vertebrados infectados por Trypanosoma cruzi. Salientamos a importância de manter a vigilância, mesmo em áreas onde a transmissão de doença de Chagas está interrompida e naquelas ainda infestadas por triatomíneos. Deve-se admitir a hipótese diagnóstica de doença de Chagas quando observados: edema palpebral (uni ou bilateral), insuficiência cardíaca, miocardite, pericardite, anasarca, quadros similares aos de síndrome nefrótica ou glomerulonefrite sem causas outras aparentes, em pacientes com dados epidemiológicos positivos. Encontro, mesmo em raras ocasiões, de triatomíneos na região ou ainda contato com alimento contaminável com formas infectantes de T. cruzi.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Genética - IBILCE

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Multivariate image analysis applied to the quantitative structure-activity relationships (MIA-QSAR) is a 2D QSAR technique that has been presenting promising outcomes for the development of new drug candidates, due to its simplicity, rapidity and low cost. In this way, the present study aims at introducing, consolidating and improving the new dimensions named aug-MIA-QSAR and aug-MIA-QSARcolor, as well as applying them to the study of neglected diseases, in order to obtain new drug targets using chemico-biological interpretation of the MIA molecular descriptors. Four compound data sets with experimental bioactivities against Chagas disease, malaria, dengue and schistosomiasis were evaluated using three approaches: MIA-QSARt, aug-MIA-QSAR and aug-MIA-QSARcolor. In general, representations of atoms as spheres with different colors and sizes proportional to the corresponding van der Waals radii (aug-MIA approaches) improved the predictive ability and interpretability in all data sets. The use of colors proportional to the Pauling´s electronegativity showed that MIA descriptors are capable of identifying periodic properties relevant for the studied activity. Finally, solid colors instead of spotlighted atoms allowed a correct identification of atoms by means of pixel values in the studies for malaria, dengue and schistosomiasis, which were, subsequently, useful for the chemical interpretation related to the bioactivity. It can be inferred that semicarbazones and thiosemicarbazones derivative with a tri-substituted ring in R1 group and a trifluoro methyl group in the R 3 position instead of a chlorine antitripanossoma resulted in higher activity. The antimalarial activity of quinolon-4(1H)imines can be improved if: 1) R1 and R2 are electron donor groups, 2) R3 has long aminoalkyl chains, and 3) R4 possesses substituents with big atomic volume. In the study for dengue, it was found that tetrapeptides with unbranched small size amino acids in the A1 and A4 positions can increase the substrate affinity (Km) to the NS3 protein, and when in A1 and A2 positions, the substrate cleavage rate (kcat). On the other hand, acidic amino acids in the A2 and A4 positions were found to be related with low substrate affinity to the NS3 protein and when present in A1, with low substrate cleavage rate. Finally, the presence of metoxy substituents in R1 (or R2) and R5 in the neolignan backbone can favor their antischistosomal activity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)