193 resultados para GUIDO, TOMAS
Resumo:
The authors carried out a series of pots and plots experiments applying arsenical and organic insecticides to cotton plants cultivated in "terra roxa" and in a sandy soil. The first results were presented in 1947, to the la. Reunião Brasileira de Ciência do Solo (First Brazilian Congress of Soil Science); they pointed out the danger resulting from the accumulation of arsenic in soils due to the constant applications of arsenicais to control cotton pests; in the course of the time, the amount of residual arsenic in the soil would determine a decrease in cotton yield caused by its toxic effect on the crop. The following conclusions were drawn from the last three experiments: 1) the field experiment conducted in a sandy soil to which lead arseniate was applied in increasing rates produced a reduction of 50 per cent in the yield (the three highest doses were responsible for this result); by this way, the pot experiment published in 1947 was confirmed); 2) in the pot experiment with "terra roxa" toxic effects appeared only in the plants receiving the last dosis of lead arsenate; this result is explained quite naturally by a considerable absorption of the AsO4 --- ion by "terra roxa" colloidal material; furthermore the CaO, P2O5 and Fe2O3 content and the pH value (higher) would decrease the arsenate solubilization in the soil considered; 3) the pot experiment with organic insecticides applied in the rates usually employed in the control of cotton pests, showed that 10% D.D.TD. and 2.5% Rotenone did not affect cotton plants cultivated in a sandy soil; however we agree with FOSTER (1951), in the point that both mineral and organic insecticides must be applied in the minimum amount as possible; we also think that experiments like those should be carried out with the known insecticides, in several soil conditions and with many crops in order to determine the maximum limits of tolerancy.
Resumo:
Nós conduzimos um levantamento populacional aéreo do cervo-do-pantanal, Blastocerus dichotomus (Illiger, 1815), no Parque Nacional de Ilha Grande e seu entorno, entre os estados do Paraná e Mato Grosso do Sul, Brasil, na estação seca. Utilizamos a técnica da contagem dupla, e a população foi estimada em 1.079 ± 207 cervos em uma área amostral de 1.081 km², corresponde a uma densidade de 0,998 ± 0,192 ind/km². A população mostrou-se mais concentrada no interior do parque, ocupando também várzeas alteradas fora dos limites do parque. Estes resultados devem subsidiar medidas de manejo e conservação da população no parque nacional e seu entorno, devido à enorme pressão antrópica sobre a população de cervos na região.
Resumo:
Realizaram os Autores um estudo histopatológico de dois casos de encefalite aguda toxoplásmica humana mostrando a distribuição dos acúmulos inflamatórios, nitidamente em relação com rêde vascular, a composição celular dêstes acúmulos e a sua histogênese. Os resultados são discutidos e comparados com material experimental de coelhos.
Resumo:
Parasites may employ particular strategies of eluding an immune response by taking advantage of those mechanisms that normally guarantee immunological self-tolerance. Much in the way as it occurs during the establishment of self-tolerance, live pathogens may induce clonal deletion, functional inactivation(anergy) and immunosupression. At this latter level, it appears that certain pathogens produce immunosupresive cytokine-like mediators or provoke like host the secrete cytokines that will compromise the anti-parasite immune response. It appears that immune responses that preferentially involve T helper l cells (secretors of interleukin-2-and interferon-y) tend to be protective, whereas T helper 2 cells (secretors of IL-4, IL5, IL-6, and IL-10), a population that antagonizes T helper cells, mediate disease susceptibility and are immunopathological reactions. Cytokines produced by T helper 2 cells mediate many symptoms of infection, including eosinophilia, mastocytosis, hyperimmunoglobulinemia, and elevated IgE levels. Administration of IL-2 and IFN-y has beneficial effects in many infections mediated by viruses, bacteria, and protozoa. The use of live vaccinia virus might be an avenue for the treatment of or vaccination against infection. We have found that a vaccinia virus expressing the gene for human IL-2, though attenuated, precipitates autoimmune disease in immunodeficient athymic mice. Thus, although T helper l cytokines may have desired immunostimulatory properties, they also may lead to unwarranted autoaggressive responses.
Resumo:
The parotid lymph nodes of naive and previously infected Balb/c mice were studied after, respectively, infection and re-infection with cercariae of Schistosoma mansoni via the ears. Schistosomula were able to pass through the lymph node by following the lymph flow or by penetrating the veins of the medullary cords. The number of nodal mast cells was higher from day 2 to 6 of primary infection; and from day 5 to 11 of re-infection. The amount of degranulating mast cells was significantly higher at day 4 of infection and at day 1 of re-infection. Eosinophils characterized the nodal inflammatory processes observed after day 5 in both primarily-infected and re-infected mice. However, only in the latter the eosinophils were able to adhere to the larval surface. In primarily-infected mice, no intranodal larva presented signs of degeneration. In contrast, in re-infected animals, some degenerating larvae were found inside eosinophilic infiltrates. The eosinophils reached the nodal tissue by migrating through the high endothelial venules and their collecting veins.
Resumo:
The synthetic n-alkyl esters of gallic acid (GA), also known as gallates, especially propyl, octyl and dodecyl gallates, are widely employed as antioxidants by food and pharmaceutical industries. The inhibitory effects of GA and 15 gallates on Herpes Simplex Virus type 1 (HSV-1) and Human Immunodeficiency Virus (HIV-1) replication were investigated here. After a preliminary screening of these compounds, GA and pentyl gallate (PG) seemed to be the most active compounds against HSV-1 replication and their mode of action was characterized through a set of assays, which attempted to localize the step of the viral multiplication cycle where impairment occurred. The detected anti-HSV-1 activity was mediated by the inhibition of virus attachment to and penetration into cells, and by virucidal properties. Furthermore, an anti-HIV-1 activity was also found, to different degrees. In summary, our results suggest that both compounds could be regarded as promising candidates for the development of topical anti-HSV-1 agents, and further studies concerning the anti-HIV-1 activity of this group of molecules are merited.
Resumo:
A new species of Pseudascarophis (Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov'eva) comb. n. due to its ambiguous diagnosis.
Resumo:
Pharmacological treatment of Chagas disease with benznidazole (BNZ) is effective in children in all stages, but it is controversial in chronically infected adults. We report the pharmacokinetics and pharmacodynamics in six adult patients with Chagas disease treated with the new BNZ formulation (ABARAX®) in doses between 2.5-5.5 mg/Kg/day. All but one patient had plasmatic BNZ concentrations within the expected range. All patients finalised treatment with nondetectable Trypanosoma cruziquantitative polymerase chain reaction, which remained nondetectable at the six month follow-up. Our data suggests parasitological responses with the new BNZ and supports the hypothesis that treatment protocols with lower BNZ doses may be effective.
Resumo:
Este trabalho é uma revisão bibliográfica, que objetiva refletir sobre stress e coping no perioperatório de câncer de mama, realizada em bases de dados on-line nacionais, abrangendo trabalhos publicados de 1996 a 2006. Foram encontrados 63 artigos, sendo selecionados 17, que foram lidos, analisados e agrupados em categorias temáticas: 1) O câncer de mama como estressor e o impacto do diagnóstico; 2) Stress e o tratamento do câncer de mama; 3) Coping e o câncer de mama, e 4) O enfermeiro como colaborador do processo de enfrentamento. Esse trabalho permitiu identificar que é vasta a literatura nacional sobre câncer de mama, mas poucos são os trabalhos que enfatizam stress e câncer de mama como processo vivenciado pela paciente. Por isso, pode dar direção a pesquisas futuras acerca dos estressores vivenciados pela mulher com câncer de mama no Brasil, e quais as estratégias de coping que ela utiliza para enfrentá-los.
Resumo:
Estudo quantitativo com o objetivo de identificar estressores, nível de estresse dos enfermeiros, estado geral de saúde e formas de enfrentamento utilizadas pelos enfermeiros no ambiente de trabalho. Os dados foram coletados utilizando-se três instrumentos: formulário para levantamento de atividades diárias; inventário de estratégias de coping; inventário sobre o estado geral de saúde. A população deste estudo foi composta de 143 enfermeiros e a maioria encontra-se com baixo nível de estresse (55,25%) e com estado regular de saúde (50,35%). Em relação às formas de enfrentamento, identificou-se resolução de problemas como o fator de maior média. Concluindo, ações educativas devem ser incentivadas, a fim de disponibilizar ferramentas para que o profissional desenvolva estratégias de coping resolutivas em seu dia a dia, minimizando o efeito do estresse no seu estado de saúde e no seu trabalho.
Resumo:
Os Programas de Residência Multiprofissional buscam romper com os paradigmas em relação à formação de profissionais para o Sistema Único de Saúde (SUS) e contribuir para qualificar os serviços de saúde a partir de ações inovadoras. Entretanto, características específicas desses programas podem agregar estressores aos residentes e, levarem à Sídrome de Burnout. Dessa forma, verificou-se a ocorrência da Síndrome de Burnout nos Residentes Multiprofissionais da Universidade Federal de Santa Maria. Este estudo trata-se de um estudo descritivo, transversal e quantitativo. Aplicaram-se um formulário de dados sociodemográficos e o Versão Human Service Survey do Marlash Burnout Inventory em 37 residentes, entre abril e junho de 2011. Observou-se que 37,84% apresentaram Alta Exaustão Emocional; 43,24%, Alta Despersonalização; e 48,65%, Baixa Realização Profissional. Na associação dos domínios, verificou-se que 27% apresentaram indicativo para Síndrome de Burnout. Os residentes pesquisados estão expostos aos estressores da profissão e da formação, o que pode favorecer a ocorrência da síndrome nesses profissionais.