120 resultados para Borlaug, Norman E. (Norman Ernest), 1914-2009


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Dentre 683 serpentes procedentes de diferentes pontos do Brasil, 16 (2,4%) apresentaram em seu sangue (em glóbulos vermelhos maturos e imaturos) Toddia ou Pirhemocyton. Denominamos provisoriamente Toddia os parasitos encontrados em Bothrops moojeni, B. pradoi, B. jararaca e Chironius flavolineatus e Pirhemocyton os encontrados em B. alternatus; fornecemos a primeira referência nestes hospedeiros. Estes parasitos foram estudados comparativamente com o objetivo de estabelecermos a extensão de suas afinidades. Com Toddia de B. moojeni realizamos técnica citoquímica para caracterização de ácidos nucleicos e encontramos positividade apenas para DNA. As maiores afinidades entre os parasitos estudados residiam nas características dos corpúsculos cromáticos e alterações celulares que determinam; observarmos quase total identidade nas maneiras como os parasitos da mesma espécie de serpente se apresentaram. Constatamos a coexistência de inclusões globóides, cristalóides e formas intermediárias associada aos parasitos de B. pradoi e B. alternatus; em C. flavolineatus encotnramos além dos cristais, raríssimas formas intermediárias entre estes e globóides. Afinidades entre Toddia e Pirhemocyton abrangendo o tipo de inclusão contrariam as descrições originais, tornando pouco válida esta separação genérica. Discutimos também os fundamentos da criação das espécies e a possível natureza virótica destes parasitos.

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New species of Issikiella and Nannobittacus are described and notes are presented on other Amazonian species of Mecoptera.

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Examination of the holotype of Lutzomyia marajoensis (Damasceno & Causey, 1944) shows this species to be identical to Lutzomyia walkeri (Newstead, 1914). The name Lutxomyia dubitans (Sherlock, 1962) is resurrected for another sand fly which has been incorrectly named L. marajoensis since 1961. Newly discovered structural differences between males and females of L walkeri from L. dubitans are presented.

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Several species of wild caught sand flies were collected in the same site where a subspecies of leishmania mexicana was isolated from the rodent Proechimys iheringi denigratus. The absence of natural infection in these sand flies permitted us to test, with relative assurance, the susceptibility of wild caught females to infection by this parasite. the success obtained in these experimental infections suggest that one or more of the sand fly species encountered in high numbers in the same site where the infected rodents were captured may be the vector(s) of this subspecies of l. mexicana.

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The objective of this work was to characterize, and compare different morphological types of hemocytes of Rhodnius prolixus, Rhodnius, Rhodnius neglectus, Triatoma infestans, Panstrongylus megistus, and Dipetalogaster maximus. This information provides the basis for studying the cellular immune systems of these insects. Seven morphological hemocyte types wereidentified by phase-contrast microscopy: prohemocytes, plasmatocytes, granular cells, cytocytes, oenocytoids, adipohemocytes and giant cells. All seven types of hemocytes are not present in every species. For example, adipohemocytes and oenocytoids were not observed in P. megistus and P. infestans, and giant cells were rarely found in any of the species studied. The hemocytes of rhodnius and Dipetalogaster are more similar to each other than those from Triatoma and Panstrongylus which in turn closely resemble each other. Emphasis is placed on methodological problems arising in this work wicah are discussed in detail.

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Haemolymph, heads, salivary glands, crops, midguts, hindguts, and Malpighian tubules from Rhodnius prolixus and Triatoma infestans were extracted in phosphate or Tris buffer saline with calcium, and tested for agglutination and lytic activities by microtitration against both vertebrateerythrocytes and cultured epimatigote forms of Trypanosoma rangeli. Haemagglutination activity against rabbit erythrocytes was found in the crop, midgut and hindgut extracts of T. infestans but only in the haemolymph of R. prolixus. Higher titres of parasite agglutinins were found in R. prolixus haemolymph than T. infestans, whilst the converse occurred for the tissue extracts. In addition, the extracts of T. infestans salivary glands, but not those of R. prolixus, showed a trypanolytic activity that was heat-inactivated and was not abolished by pre-incubation with any of the sugars or glycoproteins tested. T. infestans, which is refractory to infection by T. rangeli, thus appears to contain a much wider distribution of agglutinating and trypanolytic factors in its tissues than the more susceptible species, R. prolixus

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Human T cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes leukemia and the neurological disorder HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM/TSP). Infection with this virus - although it is distributed worldwide - is limited to certain endemic areas of the world. Despite its specific distribution and slow mutation rate, molecular epidemiology on this virus has been useful to follow the movements of human populations and routes of virus spread to different continents. In the present study, we analyzed the genetic variability of a region of the env gene of isolates obtained from individuals of African origin that live on the Pacific coast of Colombia. Sequencing and comparison of the fragment with the same fragment from different HTLV-1 isolates showed a variability ranging from 0.8% to 1.2%. Phylogenetic studies permit us to include these isolates in the transcontinental subgroup A in which samples isolated from Brazil and Chile are also found. Further analyses will be necessary to determine if these isolates were recently introduced into the American continent or if they rather correspond to isolates introduced during the Paleolithic period.

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Treatments for Chagas disease have been administered since the first attempts by Mayer & Rocha Lima (1912, 1914) and up to the drugs currently in use (nifurtimox and benznidazole), along with potential drugs such as allopurinol and first, second and third-generation antifungal agents (imidazoles and triazoles), in separate form. Several diseases such as tuberculosis, leprosy and AIDS only came under control after they were treated with associations of drugs with different mechanisms of action. This not only boosts the action of the different compounds, but also may avoid the development of parasite resistance .To this end, over the short term, we propose experimental studies on laboratory animals and clinical trials with the following associations: (i) nifurtimox (8 mg/kg/day) + benznidazole (5 mg/kg/day) x 60 consecutive days; (ii) nifurtimox (8 mg/kg/day) or benznidazole (5 mg/kg/day) + allopurinol (8-10 mg/kg/day) x 60 days and (iii) nifurtimox (8 mg/kg/day) or benznidazole (5 mg/kg/day) + ketoconazole, fluconazole or itraconazole (5-6 mg/kg/day) x 60 consecutive days. The doses of the drugs and the treatment schedules for the clinical trials must be adapted according to the side effects. From these, other double or triple associations could be made, using drugs with different mechanisms of action. This proposal does not exclude investigations on new drugs over the median and long terms, targeting other aspects of the metabolism of Trypanosoma cruzi. Until such time as the ideal drug for specific treatment of Chagas disease might be discovered, we need to develop new strategies for achieving greater efficacy with the old drugs in associations and to develop rational experimentation with new drugs.

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In this paper, we analysed the haemagglutinin (HA) gene identified by polymerase chain reaction from 90 influenza A H1N1 virus strains that circulated in Brazil from April 2009-June 2010. A World Health Organization sequencing protocol allowed us to identify amino acid mutations in the HA protein at positions S220T (71%), D239G/N/S (20%), Y247H (4.5%), E252K (3.3%), M274V (2.2%), Q310H (26.7%) and E391K (12%). A fatal outcome was associated with the D239G mutation (p < 0.0001). Brazilian HA genetic diversity, in comparison to a reference strain from California, highlights the role of influenza virus surveillance for study of viral evolution, in addition to monitoring the spread of the virus worldwide.

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We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

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São analisados os constructos t³ricos da educação interprofissional com base em duas revisões de literatura, considerado o contexto da formação dos profissionais de saúde no Brasil. Identificam-se três tipos de formação: uniprofissional, multiprofissional e interprofissional, com predomínio da primeira, que ocorre entre estudantes de uma mesma profissão de forma isolada; a segunda, entre estudantes de duas ou mais profissões de forma paralela, sem haver interação, e na terceira há aprendizagem compartilhada, com interação entre estudantes e/ou profissionais de diferentes áreas. Destaca-se a distinção entre interprofissionalidade e interdisciplinaridade, referidas, respectivamente, como a integração das práticas profissionais e das disciplinas ou áreas de conhecimento. Mediante a análise apresentada, conclui-se que no contexto brasileiro, a educação interprofissional, base para o trabalho em equipe colaborativo, ainda está restrita a iniciativas recentes, que merecem estudo.

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RESUMO Objetivo Realizar a adaptação transcultural e a validação da versão de 29-itens daReadiness for Interprofessional Learning Scale (RIPLS) para língua portuguesa falada no Brasil. Método Foram adotadas cinco etapas: três traduções, síntese, três retrotraduções, avaliação por especialistas e pré-teste. A validação contou com 327 estudantes de 13 cursos de graduação de uma universidade pública. Foram realizadas análises paralelas com o software R e a análise fatorial utilizando Modelagem de Equações Estruturais. Resultados A análise fatorial resultou em uma escala de 27 itens e três fatores: Fator 1 – Trabalho em equipe e colaboração com 14 itens (1-9, 12-16), Fator 2 – Identidade profissional, oito itens (10, 11, 17, 19, 21-24), e Fator 3 – Atenção à saúde centrada no paciente, cinco itens (25-29). Alfa de Cronbach dos três fatores foi respectivamente: 0,90; 0,66; 0,75. Análise de variância mostrou diferenças significativas nas médias dos fatores dos grupos profissionais. Conclusão Foram identificadas evidências de validação da versão em português da RIPLS em sua aplicação no contexto nacional.