950 resultados para María de Jesús de Ágreda, 1602-1665


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Nontypeable Haemophilus influenzae (NTHI) is an opportunistic pathogen that is an important cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). COPD is an inflammatory disease of the airways, and exacerbations are acute inflammatory events superimposed on this background of chronic inflammation. Azithromycin (AZM) is a macrolide antibiotic with antibacterial and anti-inflammatory properties and a clinically proven potential for AECOPD prevention and management. Relationships between AZM efficacy and resistance by NTHI and between bactericidal and immunomodulatory effects on NTHI respiratory infection have not been addressed. In this study, we employed two pathogenic NTHI strains with different AZM susceptibilities (NTHI 375 [AZM susceptible] and NTHI 353 [AZM resistant]) to evaluate the prophylactic and therapeutic effects of AZM on the NTHI-host interplay. At the cellular level, AZM was bactericidal toward intracellular NTHI inside alveolar and bronchial epithelia and alveolar macrophages, and it enhanced NTHI phagocytosis by the latter cell type. These effects correlated with the strain MIC of AZM and the antibiotic dose. Additionally, the effect of AZM on NTHI infection was assessed in a mouse model of pulmonary infection. AZM showed both preventive and therapeutic efficacies by lowering NTHI 375 bacterial counts in lungs and bronchoalveolar lavage fluid (BALF) and by reducing histopathological inflammatory lesions in the upper and lower airways of mice. Conversely, AZM did not reduce bacterial loads in animals infected with NTHI 353, in which case a milder anti-inflammatory effect was also observed. Together, the results of this work link the bactericidal and anti-inflammatory effects of AZM and frame the efficacy of this antibiotic against NTHI respiratory infection.

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Nontypeable Haemophilus influenzae (NTHi) is a frequent commensal of the human nasopharynx that causes opportunistic infection in immunocompromised individuals. Existing evidence associates lipooligosaccharide (LOS) with disease, but the specific and relative contributions of NTHi LOS modifications to virulence properties of the bacterium have not been comprehensively addressed. Using NTHi strain 375, an isolate for which the detailed LOS structure has been determined, we compared systematically a set of isogenic mutant strains expressing sequentially truncated LOS. The relative contributions of 2-keto-3-deoxyoctulosonic acid, the triheptose inner core, oligosaccharide extensions on heptoses I and III, phosphorylcholine, digalactose, and sialic acid to NTHi resistance to antimicrobial peptides (AMP), self-aggregation, biofilm formation, cultured human respiratory epithelial infection, and murine pulmonary infection were assessed. We show that opsX, lgtF, lpsA, lic1, and lic2A contribute to bacterial resistance to AMP; lic1 is related to NTHi self-aggregation; lgtF, lic1, and siaB are involved in biofilm growth; opsX and lgtF participate in epithelial infection; and opsX, lgtF, and lpsA contribute to lung infection. Depending on the phenotype, the involvement of these LOS modifications occurs at different extents, independently or having an additive effect in combination. We discuss the relative contribution of LOS epitopes to NTHi virulence and frame a range of pathogenic traits in the context of infection.

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High temperature ceramic membranes have interesting possibilities for application in areas of new and developing technologies such as hydrocarbon combustion with carbon dioxide capture and electrochemical promotion of catalysis (EPOC). However, membrane module sealing remains a significant technical challenge. In this work a borosilicate glass sealant (50SiO2·25B2O3·25Na2O, mol%) was developed to fit the requirements of sealing an air separation membrane system at intermediate temperatures (300-600 °C). The seal was assessed by testing the leak rates under a range of conditions. The parameters tested included the effect of flowrate on the leak rate, the heating and cooling rates of the reactor and the range of temperatures under which the system could operate. Tests for durability and reliability were also performed. It was found that the most favourable reactor configuration employed a reactor with the ceramic pellet placed underneath the inner chamber alumina tube (inverted configuration), using a quartz wool support to keep the membrane in place prior to sealing. Using this configuration the new glass-based seal was found to be a more suitable sealant than traditional alternatives; it produced lower leak rates at all desirable flowrates, with the potential for rapid heating and cooling and multiple cycling, allowing for prolonged usage. © 2010 Elsevier B.V. All rights reserved.

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Dense ceramics with mixed protonic-electronic conductivity are of considerable interest for the separation and purification of hydrogen and as electrochemical reactors. In this work, the hydrogen permeability of a Sr0.97Ce0.9Yb0.1O3 - δ (SCYb) membrane with a porous Pt catalytic layer on the hydrogen feed-exposed side has been studied over the temperature range 500-804 °C employing Ar as the permeate sweep gas. A SiO2-B2O3-BaO-MgO-ZnO-based glass-ceramic sealant was successfully employed to seal the membrane to the dual-chamber reactor. After 14 h of exposure to 10% H2:90% N2 at 804 °C, the H2 flux reached a maximum of 33 nmol cm- 2 s- 1, over an order of magnitude higher than that obtained on membranes of similar thickness without surface modification. The permeation rate then decreased slowly and moderately on annealing at 804 °C over a further 130 h. Thereafter, the flux was both reproducible and stable on thermal cycling in the range 600-804 °C. The results indicate an important role of superficial activation processes in the flux rate and suggest that hydrogen fluxes can be further optimised in cerate-based perovskites. © 2009 Elsevier B.V. All rights reserved.

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O Projeto que apresentamos insere-se nos estudos do Mestrado em Tradução Especializada dentro da vertente da Saúde e Ciências da Vida; é por isso que, partindo de um texto/suporte que visa promover uma alimentação saudável nas escolas (manual de referência difundido pelos Ministérios da Educação e Ciência e Ministério da Saúde de Portugal), procedemos à tradução (de português para espanhol) de um conteúdo que suscita, nos nossos dias, um grande interesse socioeducativo e cultural. É preciso destacar que o facto de ter nascido e vivido na Venezuela durante doze anos permitiu-me superar com êxito os meus estudos de espanhol na Licenciatura e no referido Mestrado; mas, ao mesmo tempo, tive que me adaptar, enquanto cidadã portuguesa, ao complexo e inacabado processo de ir interiorizando estas duas línguas – português/espanhol – tão próximas e no entanto com sistemas linguísticos bem distintos. Esta evidência encontra a sua maior justificação no grande capítulo dos erros (de forma e de significado) que consegui detetar e analisar graças à ajuda da minha professora orientadora, ao longo deste meu primeiro trabalho académico (texto traduzido para espanhol). Só agora, depois da minha primeira e “ingénua” tradução desse texto/manual, sou capaz de perceber com toda nitidez a dimensão do erro na atividade tradutora, assim como das suas consequências. Além desta importante reflexão, também o facto de elaborar este projeto permitiu-me abordar um aspeto linguístico da língua espanhola que me cativa pessoalmente (no que me diz respeito): o das variantes lexicais do castelhano nos países hispanofalantes. Não duvido em apontar um outro aspeto fundamental: o esforço de ter tido que corrigir minuciosamente e com rigor esta tarefa tradutora (com os seus respetivos comentários tradutológicos) converteu-se numa fonte de múltiplas satisfações pessoais; são aquelas que têm a ver com o cultivo de valores tais como o esforço, o espírito de superação, o exercício da responsabilidade e o (re)conhecimento da honestidade intelectual, entre outros.

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Se analizará la participación de las naciones europeas y africanas en la trata negra, que consolido la economía mercantil, de la que se derivo la revolución industrial.

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De entre los muchos repertorios de textos recogidos de la tradición oral hispánica que en los últimos años han ido publicándose, éste sobresale por un rasgo excepcional: su autor dedica igual espacio, aténcion, tiempo, rigor y esmero tanto al asunto puramente textual (los mayos) como as las cuestiones referidas al contexto folklórico (la fiesta) en el que los textos se actualizan.

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In the present work, the development of a genosensor for the event-specific detection of MON810 transgenic maize is proposed. Taking advantage of nanostructuration, a cost-effective three dimensional electrode was fabricated and a ternary monolayer containing a dithiol, a monothiol and the thiolated capture probe was optimized to minimize the unspecific signals. A sandwich format assay was selected as a way of precluding inefficient hybridization associated with stable secondary target structures. A comparison between the analytical performance of the Au nanostructured electrodes and commercially available screen-printed electrodes highlighted the superior performance of the nanostructured ones. Finally, the genosensor was effectively applied to detect the transgenic sequence in real samples, showing its potential for future quantitative analysis.

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Estudio Línea Base – ELBA Callao, primavera 2011. Inf Inst Mar Perú. 39(3-4): 149-198.- El ELBA se efectuó en el área delimitada por las islas San Lorenzo y El Frontón y la Península de La Punta, del 21 al 30 de noviembre 2011, para a) caracterizar biológica y oceanográficamente el área de estudio y b) obtener bases técnicas para el ordenamiento pesquero y acuícola. En el área predominaron sedimentos arenosos y grava de origen terrígeno. Presentó características térmicas frías al interior y cálidas al sur, con influencia de aguas costeras. La comunidad fitoplanctónica presentó abundancia de diatomeas. Se identificó zonas con alta biomasa de bentos y con altos valores de stress. Los sólidos suspendidos totales, cadmio y coliformes totales y termotolerantes sobrepasaron los límites de los estándares de calidad acuática en el Perú. Las comunidades de invertebrados más importantes fueron: concha de abanico Argopecten purpuratus, cangrejos Cancer setosus (ahora Romaleon polyodon) y C. porteri, almeja Semele spp., pulpo Octopus mimus y macroalga Macrocystis sp.; el calamar Loligo gahi usa el área para desovar.

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Contient : « Remarques touchant la psalmodie, à présenter au Chapitre général, 1648 »