133 resultados para Herrera, Luis Alberto de, 1873-1959.


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Biomphalaria prona from Lake Valencia, Venezuela (type locality) has a polymorphic shell wich in the great majority of specimens is wider, with fewer rapidly expanding whorls, the outer one subcarinate on the left side and more or less strongly deflected leftward. Besides those modal forms there are little frequent variants characterized by narrower shell with less rapidly expanding, regularly curved whorls directed forward. Recent studies have shown that such variants constitute the predominant shell phenotype in extralacustrine populations, but are anatomically and biochemically indistinguishable from the modal class of the Lake. In the present paper it is demonstrated that the nominal species Planorbis meridaensis Preston, 1907, from Mérida, Venezuela, is identical with B. prona (Martens, 1873) of wich it must be considered a junior synonym.

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Differential display technique was applied in order to identify transcripts which are present in axenic amastigotes but not in promastigotes of the Leishmania panamensis parasites. One of them was cloned and the sequence reveals an open reading frame of 364 amino acids (aprox. 40 kDa). The deduced protein is homologous to the serine/threonine protein kinases and specially to the mitogen activates protein kinases from eukaryotic species. Southern blot analysis suggest that this transcript, named lpmkh, is present in the genome of the parasite as a single copy gene. These results could imply that lpmkh could be involved in the differentiation process or the preservation of amastigotes in axenic conditions.

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The kidney trematode Paratanaisia bragai is reported for the first time parasitizing the ring-necked pheasant (Phasianus colchicus L., 1758) and the pathological alterations associated to the parasitism are referred on the basis of 50 specimens of this bird from backyard flocks in 11 counties of the state of Rio de Janeiro, Brazil after clinical examination, necropsies, and histopathological analysis. The counting of the kidney flukes was based on worms recovered from one of the kidneys, since the other was fixed in 10% formalin and then routinely processed for histopathological procedures. The prevalence of P. bragai was of 22%, with a mean intensity of 44.3, mean abundance of 9.7, and range of infection of 3-153. Parasitized birds did not present with clinical signs and kidney gross lesions. Microscopic lesions were mild and characterized by dilatation of the renal medullary collecting ducts, occasional flattening of the lining epithelium of the ducts and inflammatory reaction of variable intensity with granulocytes around the ureter branches and medullary collecting ducts. The severity and pattern of the microscopic lesions seem not to be associated to the size of the worm burden and could be related to the mechanic action of the parasites, without traumatism, in despite of the presence of the tegumentar spines in specimens of P. bragai.

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Amplicons are defective and non-integrative vectors derived from herpes simplex virus type 1. As the vector genome carries no virus genes, amplicons are both non-toxic for the infected cells and non-pathogenic for the inoculated organisms. In addition, the large transgenic capacity of amplicons, which allow delivery of up to 150 Kbp of foreign DNA, makes these vectors one of the most powerful, interesting and versatile gene delivery platforms. We present here recent technological developments that have significantly improved and extended the use of amplicons, both in cultured cells and in living organisms. In addition, this review also discusses the many difficulties still pending to be solved, in order to achieve stable and physiologically regulated transgene expression.

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Malaria is the most important parasitic disease worldwide, responsible for an estimated 225 million clinical cases each year. It mainly affects children, pregnant women and non-immune adults who frequently die victims of cerebral manifestations and anaemia. Although the contribution of the American continent to the global malaria burden is only around 1.2 million clinical cases annually, there are 170 million inhabitants living at risk of malaria transmission in this region. On the African continent, where Plasmodium falciparum is the most prevalent human malaria parasite, anaemia is responsible for about half of the malaria-related deaths. Conversely, in Latin America (LA), malaria-related anaemia appears to be uncommon, though there is a limited knowledge about its real prevalence. This may be partially explained by several factors, including that the overall malaria burden in LA is significantly lower than that of Africa, that Plasmodium vivax, the predominant Plasmodium species in the region, appears to display a different clinical spectrus and most likely because better health services in LA prevent the development of severe malaria cases. With the aim of contributing to the understanding of the real importance of malaria-related anaemia in LA, we discuss here a revision of the available literature on the subject and the usefulness of experimental animal models, including New World monkeys, particularly for the study of the mechanisms involved in the pathogenesis of malaria.

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Immunological diagnostic methods for Trypanosoma cruzi depend specifically on the presence of antibodies and parasitological methods lack sensitivity during the chronic and “indeterminate” stages of the disease. This study performed a serological survey of 1,033 subjects from 52 rural communities in 12 of the 18 municipalities in the state of Querétaro, Mexico. We detected anti-T. cruzi antibodies using the following tests: indirect haemagglutination assay (IHA), indirect immunofluorescence assay (IFA), ELISA and recombinant ELISA (rELISA). We also performed Western blot (WB) analysis using iron superoxide dismutase (FeSOD), a detoxifying enzyme excreted by the parasite, as the antigen. Positive test results were distributed as follows: ELISA 8%, rELISA 6.2%, IFA and IHA 5.4% in both cases and FeSOD 8%. A comparative study of the five tests was undertaken. Sensitivity levels, specificity, positive and negative predictive values, concordance percentage and kappa index were considered. Living with animals, trips to other communities, gender, age, type of housing and symptomatology at the time of the survey were statistically analysed using SPSS software v.11.5. Detection of the FeSOD enzyme that was secreted by the parasite and used as an antigenic fraction in WBs showed a 100% correlation with traditional ELISA tests.

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Gold-mining may play an important role in the maintenance of malaria worldwide. Gold-mining, mostly illegal, has significantly expanded in Colombia during the last decade in areas with limited health care and disease prevention. We report a descriptive study that was carried out to determine the malaria prevalence in gold-mining areas of Colombia, using data from the public health surveillance system (National Health Institute) during the period 2010-2013. Gold-mining was more prevalent in the departments of Antioquia, Córdoba, Bolívar, Chocó, Nariño, Cauca, and Valle, which contributed 89.3% (270,753 cases) of the national malaria incidence from 2010-2013 and 31.6% of malaria cases were from mining areas. Mining regions, such as El Bagre, Zaragoza, and Segovia, in Antioquia, Puerto Libertador and Montelíbano, in Córdoba, and Buenaventura, in Valle del Cauca, were the most endemic areas. The annual parasite index (API) correlated with gold production (R2 0.82, p < 0.0001); for every 100 kg of gold produced, the API increased by 0.54 cases per 1,000 inhabitants. Lack of malaria control activities, together with high migration and proliferation of mosquito breeding sites, contribute to malaria in gold-mining regions. Specific control activities must be introduced to control this significant source of malaria in Colombia.

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A necessidade manifesta de inclusão no processo de produção da vida material através do trabalho, de uma parcela da população usuária de serviço de saúde mental, deu origem a este estudo. Para apreender o significado do trabalho utilizou-se o referencial do materialismo histórico e dialético, fundamentado no conceito de reabilitação psicossocial, e o fez através da análise dos discursos dos usuários. O cenário é o Centro de Atenção Psicossocial Prof. Luis Cerqueira (CAPS). Os resultados indicam a compreensão do trabalho como um instrumento que possibilita aos usuários acessar o campo dos direitos sociais.

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OBJETIVO: Documentar las creencias y las prácticas de las parteras tradicionales respecto al embarazo parto y puerperio. MÉTODOS: Aprovechando un curso de capacitación de 160 parteras tradicionales locales de las regiones Media y Huasteca del Estado de San Luis Potosí, México, dos de las enfermeras-instructoras entrevistaron a 25 de los capacitandos, apoyadas por un miembro de las comunidades náhuatl y tenek. La identidad de los participantes se mantiene anónima y se obtuvo permiso para publicar los resultados mediante consentimiento informado. RESULTADOS: Las prácticas de las parteras (os) tradicionales son comunes en los grupos sociales que carecen de servicios de salud. Sus funciones no están limitadas al parto e incluyen nutrición, cuidados prenatales, del puerperio y la lactancia, así como apoyo afectivo emocional de las madres parturientas y sus familiares. En este estudio se registraron varios mitos y terapias tradicionales. CONCLUSIÓN: Los recursos de la terapia tradicional y de la atención primaria de la salud de las parteras Náhuatl y Tenek son útiles y benéficos para los cuidados perinatales.