409 research outputs found

    Effect of the presence of surfactant and ionic liquids on the esterification of oleic acid catalyzed by immobilized lipase

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    Ionic liquids (ILs) and surfactants are widely used in order to increase the catalytic efficiency of lipases. In this sense, the present study aimed to evaluate the potential of different ionic liquids (C4MIM.Ac, C4MIM.HSO4, C4MIM.TF2N, C4MIM.BF4, C12MIM.I, and C12MIM.Cl), Aliquat 336 and di-2-ethylhexyl sodium sulfosuccinate (AOT) as adjuvants in the esterification of oleic acid with different alcohols catalyzed by Novozyme 435. First of all, it evaluates the effect of alkyl chain length of the alcohol and the positioning of the hydroxyl group. The selection of additives, made with isopropyl alcohol, pointed AOT and C4MIM.Ac as adjuvants effective on the potential of esterification of the enzyme (an increase of 35% in the potential of esterification). Using methanol, ethanol and 3-methyl-1-butanol, the C4MIM.Ac was proven not to be efficient, while the AOT shows adjuvant effect in the esterification of oleic acid with methanol (increasing in catalytic efficiency of enzyme in 21%).Key words: Esterification, di-2-ethylhexyl sodium sulfosuccinate (AOT), Ionic Liquids, Novozyme 435

    High yielding synthesis of N-ethyl dehydroamino acids

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    Recently we reported the use of a sequence of alkylation and dehydration methodologies to obtain N-ethyl-α, β-dehydroamino acid derivatives. The application of this N-alkylation procedure to several methyl esters of β, β-dibromo and β--bromo, β-substituted dehydroamino acids protected with standard amine protecting groups was subsequently reported. The corresponding N-ethyl, β-bromo dehydroamino acid derivatives were obtained in fair to high yields and some were used as substrates in Suzuki cross coupling reactions to give N-ethyl, β, β-disubstituted dehydroalanine derivatives. Herein, we further explore N-ethylation of β-halo dehydroamino acid derivatives using triethyloxonium tetrafluoroborate as alkylating agent but substituting N,N-diisopropylethylamine for potassium tert-butoxide as auxiliary base. In these conditions, for all β-halo dehydroamino acid derivatives, reactions were complete and the N-ethylated derivative could be isolated in high yield. This method was also applied for N-ethylation of non-halogenated dehydroamino acids. Again, with all compounds the reactions were complete and the N-ethyl dehydroamino acid derivatives could be isolated in high yields. Some of these N-ethyl dehydroamino acid methyl ester derivatives were converted in high yields to their corresponding acids and coupled to an amino acid methyl ester to give N-ethyl dehydrodipeptide derivatives in good yields. Thus, this method constitutes a general procedure for high yielding synthesis of N-ethylated dehydroamino acids, which can be further applied in peptide synthesis.Foundation for Science and Technology (FCT)-Portugal and Fundo Europeu de Desenvolvimento Regional (FEDER) for financial support to Chemistry Centre of University of Minho. The NMR spectrometer Bruker Avance II+ 400 is part of the National NMR Network and was purchased in the framework of the National Program for Scientific Re-equipment; contract REDE/1517/RMN/2005, with funds from POCI 2010, FEDER and FCT

    Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees

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    email Suzanne orcd idCopyright: © 2015 Williams et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Application of Chinese Jun-Cao technique for the production of Brazilian Ganoderma lucidum strains

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    Ganoderma lucidum is a medicinal mushroom traditionally used in China against a wide range of diseases such as cancer and also for its prevention. In this work, commercial Chinese strains G. lucidum were compared to wild Brazilian strains aiming to determine the cultivation potential through the use of Jun-Cao. Six formulations were tested and the strains presented good response to the applied method. In general, the mixture between the grass and wood was well suited for the basidiomycetes, contributing to the preparation of substrates that generated better results in Jun Cao

    Qualidade dos cuidados de enfermagem e satisfação do paciente atendido em um hospital de ensino

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    OBJECTIVES: assess the quality of nursing care, the patients' satisfaction and the correlation between both. METHOD: cross-sectional study, involving 275 patients hospitalized at a teaching hospital in the Central-West of Brazil. The data were collected through the simultaneous application of three instruments. Next, they were included in an electronic database and analyzed in function of the positivity, median value and Spearman's correlation coefficients. RESULTS: among the nursing care assessed, only two were considered safe - hygiene and physical comfort; nutrition and hydration - while the remainder were classified as poor. Nevertheless, the patients were satisfied with the care received in the domains assessed: technical-professional, confidence and educational. This can be justified by the weak to moderate correlation that was observed among these variables. CONCLUSION: Despite the quality deficit, the patients' satisfaction level with the nursing care received was high. These results indicate that the institution needs to center its objectives on a continuing evaluation system of the care quality, aiming to attend to the patients' expectations.OBJETIVOS: evaluar la calidad de los cuidados de enfermería, la satisfacción del paciente y la correlación entre ambos. MÉTODO: estudio trasversal con 275 pacientes internados en un hospital de enseñanza de la región Centro-Oeste de Brasil. Los datos fueron recolectados mediante la aplicación simultánea de tres instrumentos. A seguir, fueron digitalizados en un banco de datos electrónico y analizados en función de la positividad, valor de mediana y coeficientes de correlación de Spearman. RESULTADOS: entre los cuidados de enfermería evaluados, solamente dos fueron considerados seguros - higiene y conforto físico; nutrición e hidratación - y los demás clasificados como pobres. Sin embargo, los pacientes se mostraron satisfechos con los cuidados recibidos en los dominios evaluados: técnico-profesional, confianza y educacional. Eso puede ser justificado por la correlación débil a moderada observada entre esas variables. CONCLUSIÓN: A pesar del déficit de cualidad, fue encontrado alto nivel de satisfacción de los pacientes con los cuidados de enfermería recibidos. Tales resultados indican la necesidad de que la institución centre sus objetivos en un sistema de evaluación permanente de la cualidad del cuidado, visando atender a las expectativas de los pacientes.OBJETIVOS: avaliar a qualidade dos cuidados de enfermagem, a satisfação do paciente e a correlação entre ambos. MÉTODO: estudo transversal, realizado com 275 pacientes internados em um hospital de ensino da Região Centro-Oeste do Brasil. Os dados foram obtidos por meio da aplicação simultânea de três instrumentos. A seguir, foram digitados em banco de dados eletrônico e analisados em função da positividade, valor de mediana e coeficientes de correlação de Spearman. RESULTADOS: dentre os cuidados de enfermagem avaliados, apenas dois foram considerados seguros - higiene e conforto físico; nutrição e hidratação - e os demais foram classificados como pobres. Todavia, os pacientes mostraram-se satisfeitos com os cuidados recebidos nos domínios avaliados: técnico-profissional, confiança e educacional. Isso pode ser justificado pela correlação fraca a moderada observada entre essas variáveis. CONCLUSÃO: apesar do déficit de qualidade, houve alto nível de satisfação dos pacientes com os cuidados de enfermagem recebidos. Tais resultados apontam a necessidade de a instituição centrar seus objetivos num sistema de avaliação permanente da qualidade do cuidado, visando o atendimento das expectativas dos pacientes

    Comparative randomised trial of high and conventional doses of praziquantel in the treatment of schistosomiasis mansoni

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    The efficacy of oral praziquantel in the treatment of schistosomiasis has been considered low by most public health institutions. In this paper, we compared the efficacy of two dosages of praziquantel (80 mg/kg vs. 50 mg/kg) in patients with chronic schistosomiasis mansoni. Two hundred eighty-eight patients with schistosomiasis from a community in Brazil were randomly divided into two groups: 145 patients (Group 1) received 80 mg/kg body weight of oral praziquantel divided in two equal doses with 1 h interval and 143 patients (Group 2) received 50 mg/kg body weight of oral praziquantel. To keep the study masked, patients in Group 2 received placebo 1 h after the first dose. All patients were subjected to clinical and ultrasonographic examination. Cure assessment was performed by repeating two stool examinations, by a quantitative method, at 30, 90 and 180 days after treatment. The morbidity of schistosomiasis was low, with a few cases of light periportal thickening and 16 cases of mild splenomegaly. The cure rates were 89.7% for Group 1 and 83.9% for Group 2. There was no difference in the efficacy of both therapeutic dosages of praziquantel assayed. The adverse reactions were more frequent with higher dosage
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