914 resultados para POLY(EPSILON-CAPROLACTONE) C BLOCK


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Structural analysis carried out on a segment of the Neoproterozoic Ribeira Belt, southeastern Brazil, show that it represents part of the transpressive dextral orogen related to the Central Mantiqueira Province. NNE-trending and steeply dipping regional mylonitic belts form anastomosed geometry, and describe a map-scale, S-C-like structure that is characterized by their deflection towards NE near the Além Paraíba Lineament. Lithological and structural control related to deformation partition were responsible for the formation of felsic mylonitic granulites with S-type granites lenses developed in ductile shear zones, alternated with less deformed intermediate to basic granulites associated with charnockites. The dextral shear sense indicators are consistent with transpressive deformation in the region and are common especially at the border of the main shear zones. The presence of S-type leucogranite may lead to variations of linear and planar relationships, which result in local extension zones. These elements are consistent with oblique continental collision considering the São Francisco Craton as a stable block.

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The present article reviews different aspects of the chemistry of two widely used β-lactam antibiotics Clavulanic Acid and Cephamycin C. The article discusses important details of the biosynthesis of these compounds, their action mechanism and, principally, the methods employed in their isolation and purification, in accordance with the available literature. Despite the large quantity of available articles and patents concerning β-lactam antibiotics, those which describe the isolation and purification of Clavulanic Acid and Cephamycin C are rare. Overall, the intention of this article is to discuss the up-to-date scientific research related to the compounds under review.

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The flavonoids present in sugarcane (Saccharum officinarum) extracts were analyzed by liquid chromatography - mass spectrometry (LC-MS), and a study of the fragmentation patterns of selected flavonoids was conducted using orthogonal acceleration time-of-flight electrospray ionization mass spectrometry (ESI-oa-ToF MS). Seven C- and O-glycosylflavones were identified in the extracts, namely, schaftoside, isoschaftoside, luteolin-8-C-(rhamnosylglucoside), vitexin, orientin, tricin-7-O-neohesperidoside and tricin-7-O-glucoside. Of these, five were identified in the absence of direct comparison with their respective standards. The described method also permitted the differentiation of the 6-C and 8-C isomeric flavones, schaftoside and isoschaftoside. The combination of fragmentation data and exact mass measurement showed to be complimentary to the HPLC-UV-MS techniques previously utilized for isomers discrimination in sugarcane studies.

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In this communication we describe the application of a conductive polymer gas sensor as an air pressure sensor. The device consists of a thin doped poly(4'-hexyloxy-2,5-biphenylene ethylene) (PHBPE) film deposited on an interdigitated metallic electrode. The sensor is cheap, easy to fabricate, lasts for several months, and is suitable for measuring air pressures in the range between 100 and 700 mmHg.

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Um inquérito de base populacional foi conduzido na população urbana de todas as capitais e do Distrito Federal no Brasil para fornecer informações sobre a prevalência de hepatites virais e fatores de risco, entre 2005 e 2009. Este artigo descreve o delineamento e a metodologia do estudo que envolveu a população com idade entre 5 e 19 anos para hepatite A e 10 a 69 anos para hepatite B e C. As entrevistas e amostras de sangue foram obtidas através de visitas domiciliares e a amostra selecionada a partir de uma amostragem estratificada em múltiplos estágios (por conglomerado) com igual probabilidade para cada domínio de estudo (região e faixa etária). Nacionalmente, 19.280 residências e ~31.000 indivíduos foram selecionados. O tamanho da amostra foi suficiente para detectar uma prevalência em torno de 0,1% e para avaliar os fatores de risco por região. A metodologia apresentou-se viável para distinguir entre diferentes padrões epidemiológicos da hepatite A, B e C. Estes dados serão de valia para a avaliação das políticas de vacinação e para o desenho de estratégias de controle.

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Chronic hepatitis C is often a progressive, fibrotic disease that can lead to cirrhosis and other complications. The recommended therapy is a combination of interferon and ribavirin. Besides its antiviral action, interferon is considered to have antifibrotic activity. We examined the outcome of hepatic fibrosis and inflammation in chronic hepatitis C patients who were non-responders to interferon. We made a case series, retrospective study, based on revision of medical records and reassessment of liver biopsies. For inclusion, patients should have been treated with interferon alone or combined with ribavirin, with no virological response (non responders and relapsers) and had a liver biopsy before and after treatment. Histological evaluation included: i-outcome of fibrosis and necroinflammation; ii-annual fibrosis progression rate evaluation, before and after treatment. Seventy-five patients were included. Fifty-seven patients (76%) did not show progression of fibrosis after treatment, compared to six (8%) before treatment (p < 0.001). The mean annual fibrosis progression rate was significantly reduced after treatment (p = 0.036). Inflammatory activity improved in 19 patients (25.3%). The results support the hypothesis of an antifibrotic effect of interferon-based therapy, in non-responder patients. There was evidence of anti-inflammatory effects of treatment in some patients.

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FUNDAMENTO: Vários estudos sugerem que a proteína-C reativa (PCR) se correlaciona com doença arterial coronariana em adultos. Entretanto, essa associação ainda é pouco explorada em adolescentes. OBJETIVO: Avaliar a associação entre a PCR e os fatores de risco cardiovascular em adolescentes obesos. MÉTODOS: Oitenta e quatro adolescentes (12,6 ± 1,3 anos), ambos os sexos, foram distribuídos nos grupos Eutrófico (n = 28), Sobrepeso (n = 28) e Obeso (n = 28), segundo o índice de massa corpórea (IMC). A concentração de PCR (ELISA ultrassensível), o perfil lipídico e o conteúdo de anticorpos anti-LDLox (ELISA) foram determinados após jejum de 12h. RESULTADOS: Os grupos foram semelhantes quanto a idade (p = 0,13) e sexo (p = 0,83). Colesterol total, HDL-C, CT/HDL-C e LDL-C/HDL-C apresentaram diferenças significativas entre os grupos Eutrófico e Obeso. Não houve variação significativa no conteúdo de anticorpos anti-LDLox. Os valores de PCR foram diferentes entre os três grupos (p < 0,01). PCR apresentou associação significativa com IMC (β = 2,533), CB (β = 2,645) e CC (β = 2,945), CT (β = 0,006), LDL-C (β = 0,006) e anticorpos anti-LDLox (β = 0,383) e negativa entre HDL-C (β = -0,017). CONCLUSÃO: Os resultados indicam que a PCR se associa significativamente com marcadores de risco cardiovascular em adolescentes.

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O objetivo deste trabalho foi de analisar morfometricamente fragmentos histológicos do baço de animais normais e diabéticos, comparando os resultados encontrados e relacionando-os ao sexo e a suplementação da vitamina C. Foram utilizados 32 ratos Wistar, os quais foram analisados número de vasos, o número de folículos germinativos (polpa branca) e o diâmetro dos vasos de cada animal. As análises histológicas e morfometricas foram feitas em amostras de 5µm de espessura demonstrando que: na quantidade de folículos germinativos, observamos resultados comparando, independente do sexo, animais controles suplementados com vitamina C e controles não suplementados (p≤0,05; F=0,1452); na quantidade de vasos, observamos resultados comparando, fêmeas diabéticas suplementadas pela vitamina C e fêmeas diabéticas não suplementadas (pd"0,05; F=6.8893); e no diâmetro dos vasos, observamos resultados comparando fêmeas, tanto no grupo controle quanto ao grupo diabético, suplementadas pela vitamina C quando comparadas às fêmeas não suplementadas pela vitamina C (p<0,05; U=121.50; Z(U)=2.1234) e (p<0,05; F=4.8134). De um modo geral, a indução de diabetess modifica o diâmetro vascular nas fêmeas e que a administração de vitamina C interfere nos dados métricos relativos ao diâmetro vascular somente nas fêmeas.

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The objective of this study was to evaluate the nutritional traits and in vitro digestibility of silages from different corn cultivars harvested at two cutting heights. It was evaluated 11 cultivars (Dina 766, Dina 657, Dina 1000, P 3021, P 3041, C 805, C 333, AG 5011, FO 01, Dina co 9621 and BR 205) harvest 5 cm above ground (low) and 5 cm below the intersection of the first ear (high). It was used a random block design (three blocks), arranged in a 11 × 2 factorial scheme. Silages from plants harvested at high cutting height presented average content of dry matter significantly superior to silages from plants harvested at low height. Cultivars FO 01, AG 5011, Dina co 9621 and Dina 766 presented greater content of crude protein than cultivars C 805, P 3041 and P 3021, which presented the lowest contents of this nutrient. The raise in the cut height increased in vitro dry matter true digestibility coefficients and in vitro dry matter digestibility of silage evaluated. The increase in cut height improved nutritive value of silages by decreasing concentrations of fibrous fractions and increasing in vitro dry matter digestibility.

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A clamidiose ou ornitose é uma doença infecciosa, causada pela bactéria Chlamydophila psittaci, que acomete aves e mamíferos. Trata-se de uma das principais zoonoses de origem aviária. A transmissão ocorre principalmente por inalação de secreções contaminadas. Os sinais clínicos mais comuns incluem alterações no sistema gastrointestinal, respiratório e ocular, porém é possível encontrar aves infectadas sem sinais aparentes, dificultando a identificação da doença. O diagnóstico definitivo em aves vivas pode ser difícil, devido às características da infecção pela bactéria. Há duas principais abordagens para o diagnóstico, a primeira envolve a detecção direta da bactéria e a segunda implica a detecção de anticorpos anti-Chlamydophila sp. O tratamento é longo e envolve o uso de tetraciclinas, quinolonas ou macrolídeos, durante 21-45 dias, dependendo da espécie e do fármaco de escolha. Atualmente, o Brasil não dispõe de medidas padronizadas que visam a guiar o clínico na identificação, manejo e tratamento para a doença. Tais medidas tornam-se necessárias, bem como a pesquisa de novos métodos diagnósticos e auxiliares para a doença.

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Vários estudos sugerem que a proteína-C reativa (PCR) se correlaciona com doença arterial coronariana em adultos. Entretanto, essa associação ainda é pouco explorada em adolescentes. Avaliar a associação entre a PCR e os fatores de risco cardiovascular em adolescentes obesos. Oitenta e quatro adolescentes (12,6 ± 1,3 anos), ambos os sexos, foram distribuídos nos grupos Eutrófico (n = 28), Sobrepeso (n = 28) e Obeso (n = 28), segundo o índice de massa corpórea (IMC). A concentração de PCR (ELISA ultrassensível), o perfil lipídico e o conteúdo de anticorpos anti-LDLox (ELISA) foram determinados após jejum de 12h. Os grupos foram semelhantes quanto a idade (p = 0,13) e sexo (p = 0,83). Colesterol total, HDL-C, CT/HDL-C e LDL-C/HDL-C apresentaram diferenças significativas entre os grupos Eutrófico e Obeso. Não houve variação significativa no conteúdo de anticorpos anti-LDLox. Os valores de PCR foram diferentes entre os três grupos (p < 0,01). PCR apresentou associação significativa com IMC (β = 2,533), CB (β = 2,645) e CC (β = 2,945), CT (β = 0,006), LDL-C (β = 0,006) e anticorpos anti-LDLox (β = 0,383) e negativa entre HDL-C (β = -0,017). Os resultados indicam que a PCR se associa significativamente com marcadores de risco cardiovascular em adolescentes

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Background & aims. This study aimed to determine the relationship between blood lead concentrations and calcium, iron and vitamin C dietary intakes of pregnant women. Methods. Included in the study were 55 women admitted to a hospital, for delivery, from June to August 2002. A food frequency questionnaire was applied to determine calcium, iron and vitamin C intakes, and a general questionnaire to obtain data on demographic-socioeconomic condition, obstetric history, smoking habit, and alcohol intake. Blood lead and haemoglobin were determined, respectively, by atomic absorption spectrometry and by the haemoglobinometer HemoCue®. Multiple linear regression models were used to determine the relationship between blood lead and calcium, iron and vitamin C intakes, and haemoglobin levels, controlling for confounders. Results. The final model of the regression analysis detected an inverse relationship between blood lead and age of the women (p=0.011), haemoglobin (p=0.001), vitamin C (p=0.012), and calcium intake (p<0.001) (R2=0.952). One hundred percent, 98.2% and 43.6% of the women were below the adequate intake (AI) for calcium, and below the recommended dietary allowances (RDA) for iron, and vitamin C, respectively. Conclusion. Despite the small sample size, the results of this study suggest that maternal age, haemoglobin, vitamin C intake, and calcium intake may interfere with blood concentrations of lead

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Background: In Brazil, heart failure leads to approximately 25,000 deaths per year. Abnormal calcium handling is a hallmark of heart failure and changes in genes encoding for proteins involved in the re-uptake of calcium might harbor mutations leading to inherited cardiomyopathies. Phospholamban (PLN) plays a prime role in cardiac contractility and relaxation and mutations in the gene encoding PLN have been associated with dilated cardiomyopathy. In this study, our objective was to determine the presence of the -36A>C alteration in PLN gene in a Brazilian population of individuals with HF and to test whether this alteration is associated with heart failure or with a worse prognosis of patients with HF. Methods: We genotyped a cohort of 881 patients with HF and 1259 individuals from a cohort of individuals from the general population for the alteration -36A>C in the PLN gene. Allele and genotype frequencies were compared between groups (patients and control). In addition, frequencies or mean values of different phenotypes associated with cardiovascular disease were compared between genotypic groups. Finally, patients were prospectively followed-up for death incidence and genotypes for the -36A>C were compared regarding mortality incidence in HF patients. Results: No significant association was found between the study polymorphism and HF in our population. In addition, no association between PLN -36A>C polymorphism and demographic, clinical and functional characteristics and mortality incidence in this sample of HF patients was observed. Conclusion: Our data do not support a role for the PLN -36A>C alteration in modulating the heart failure phenotype, including its clinical course, in humans.

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In recent years, the Me-Si-B (Me-metal) ternary systems have received considerable attention aiming at the development of high-temperature structural materials. Assuming that any real application of these materials will rely on multicomponent alloys, as is the case of Ni-base superalloys, phase equilibria data of these systems become very important. In this work, results are reported on phase equilibria in the V-Si-B system, and are summarized in the form of an isothermal section at 1600 A degrees C for the V-VSi(2)-VB region. Several alloys of different compositions were prepared via arc melting and then heat-treated at 1600 A degrees C under high vacuum. All the materials in both as-cast and heat-treated conditions were characterized through x-ray diffraction, scanning electron microscopy, and selected alloys via wavelength dispersive spectroscopy. A negligible solubility of B in the V(3)Si, V(5)Si(3) (T(1)), and V(6)Si(5) phases as well as of Si in V(3)B(2) and VB phases was noted. Two ternary phases presenting the structures known as T(2) (Cr(5)B(3)-prototype) and D8(8) (Mn(5)Si(3)-prototype) were observed in both as-cast and heat-treated samples. It is proposed that at 1600 A degrees C the homogeneity range of T(2) extends approximately from 5 at.% to 12 at.% Si at constant vanadium content and the composition of D8(8) phase is close to V(59.5)Si(33)B(7.5) (at.%).

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We consider distributions u is an element of S'(R) of the form u(t) = Sigma(n is an element of N) a(n)e(i lambda nt), where (a(n))(n is an element of N) subset of C and Lambda = (lambda n)(n is an element of N) subset of R have the following properties: (a(n))(n is an element of N) is an element of s', that is, there is a q is an element of N such that (n(-q) a(n))(n is an element of N) is an element of l(1); for the real sequence., there are n(0) is an element of N, C > 0, and alpha > 0 such that n >= n(0) double right arrow vertical bar lambda(n)vertical bar >= Cn(alpha). Let I(epsilon) subset of R be an interval of length epsilon. We prove that for given Lambda, (1) if Lambda = O(n(alpha)) with alpha < 1, then there exists epsilon > 0 such that u vertical bar I(epsilon) = 0 double right arrow u 0; (2) if Lambda = O(n) is uniformly discrete, then there exists epsilon > 0 such that u vertical bar I(epsilon) = 0 double right arrow u 0; (3) if alpha > 1 and. is uniformly discrete, then for all epsilon > 0, u vertical bar I(epsilon) = 0 double right arrow u = 0. Since distributions of the above mentioned form are very common in engineering, as in the case of the modeling of ocean waves, signal processing, and vibrations of beams, plates, and shells, those uniqueness and nonuniqueness results have important consequences for identification problems in the applied sciences. We show an identification method and close this article with a simple example to show that the recovery of geometrical imperfections in a cylindrical shell is possible from a measurement of its dynamics.