1000 resultados para Vias de acesso vascular


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Este artigo apresenta evidências produzidas a partir da Pesquisa Nacional por Amostra de Domicílios de 2006 sobre as relações entre classe, raça e acesso ao ensino superior. O objetivo é preencher a lacuna de conhecimento que ainda persiste sobre o tema, a despeito do intenso debate público sobre a adoção de políticas de promoção de acesso equitativo ao ensino superior para negros ou para pobres. Os indicadores apresentados apontam a existência de associações entre classe, raça e acesso ao ensino superior para além dos efeitos das relações entre classe, raça e término do ensino médio. Conclui apontando a necessidade simultânea de quotas sociais e raciais para atingir o objetivo de atacar a desigualdade de acesso à universidade.

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High mortality in newborn babies with congenital diaphragmatic hernia (CDH) is principally due to persistent pulmonary hypertension. ATP-dependent potassium (K(ATP)) channels might modulate pulmonary vascular tone. We have assessed the effects of Pinacidil, a K(ATP) channel opener, and glibenclamide (GLI), a K(ATP) channel blocker, in near full-term lambs with and without CDH. In vivo, pulmonary hemodynamics were assessed by means of pressure and blood flow catheters. In vitro, we used isolated pulmonary vessels and immunohistochemistry to detect the presence of K(ATP) channels in pulmonary tissue. In vivo, pinacidil (2 mg) significantly reduced pulmonary vascular resistance (PVR) in both controls and CDH animals. GLI (30 mg) significantly increased pulmonary arterial pressure (PAP) and PVR in control animals only. In vitro, pinacidil (10 microM) relaxed, precontracted arteries from lambs with and without CDH. GLI (10(-5) microM) did not raise the basal tone of vessels. We conclude that activation of K(ATP) channels could be of interest to reduce pulmonary vascular tone in fetal lambs with CDH, a condition often associated with persistent pulmonary hypertension of the newborn.

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ABSTRACT BACKGROUND: Chronic mountain sickness (CMS) is a major public health problem characterized by exaggerated hypoxemia and erythrocytosis. In more advanced stages, these patients often present functional and structural changes of the pulmonary circulation, but there is little information on the systemic circulation. In patients suffering from diseases associated with chronic hypoxemia at low altitude, systemic vascular function is altered. We hypothesized that patients with CMS display systemic vascular dysfunction that may predispose them to increased systemic cardiovascular morbidity. METHODS: To test this hypothesis, we assessed systemic endothelial function (by flow- mediated dilation, FMD), arterial stiffness and carotid intima-media thickness and arterial oxygenation (SaO(2)) in 23 patients with CMS without additional classical cardiovascular risk factors and 27 age-matched healthy mountain dwellers born and permanently living at 3600 m. For some analyses subjects were classified according to baseline SaO(2) quartiles; FMD of the highest quartile subgroup (SaO(2) ≥90%) was used as reference value for post-hoc comparisons. RESULTS: Patients with CMS displayed marked systemic vascular dysfunction, as evidenced by impaired FMD (4.6±1.2 vs. 7.6±1.9%, CMS vs. controls, P<0.0001), greater pulse wave velocity (10.6±2.1 vs. 8.4±1.0 m/s, P<0.001) and carotid intima-media thickness (690±120 vs. 570±110 μm, P=0.001). A positive relationship existed between SaO(2) and FMD (r=0.62, P<0.0001). Oxygen inhalation improved (P<0.001), but did not normalize FMD in patients with CMS; whereas it normalized FMD in hypoxemic controls (SaO(2) <90%) and had no detectable effect in normoxemic (SaO(2) ≥90%) control subjects. CONCLUSIONS: Patients with CMS display marked systemic vascular dysfunction. Structural and functional alterations contribute to this problem that may predispose these patients to premature cardiovascular disease. Clinical Trials Gov Registration # NCT01182792.

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Perinatal adverse events such as limitation of nutrients or oxygen supply are associated with the occurrence of diseases in adulthood, like cardiovascular diseases and diabetes. We investigated the long-term effects of perinatal hypoxia on the lung circulation, with particular attention to the nitric oxide (NO)/cGMP pathway. Mice were placed under hypoxia in utero 5 days before delivery and for 5 days after birth. Pups were then bred in normoxia until adulthood. Adults born in hypoxia displayed an altered regulation of pulmonary vascular tone with higher right ventricular pressure in normoxia and increased sensitivity to acute hypoxia compared with controls. Perinatal hypoxia dramatically decreased endothelium-dependent relaxation induced by ACh in adult pulmonary arteries (PAs) but did not influence NO-mediated endothelium-independent relaxation. The M(3) muscarinic receptor was implicated in the relaxing action of ACh and M(1) muscarinic receptor (M(1)AChR) in its vasoconstrictive effects. Pirenzepine or telenzepine, two preferential inhibitors of M(1)AChR, abolished the adverse effects of perinatal hypoxia on ACh-induced relaxation. M(1)AChR mRNA expression was increased in lungs and PAs of mice born in hypoxia. The phosphodiesterase 1 (PDE1) inhibitor vinpocetine also reversed the decrease in ACh-induced relaxation following perinatal hypoxia, suggesting that M(1)AChR-mediated alteration of ACh-induced relaxation is due to the activation of calcium-dependent PDE1. Therefore, perinatal hypoxia leads to an altered pulmonary circulation in adulthood with vascular dysfunction characterized by impaired endothelium-dependent relaxation and M(1)AChR plays a predominant role. This raises the possibility that muscarinic receptors could be key determinants in pulmonary vascular diseases in relation to "perinatal imprinting."

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Background: Excessive mediastinal shift into the vacated thoracic cavity after pneumonectomy can result in dyspnea without hypoxemia by compression of the tracheobronchial tree, a phenomenon called postpneumonectomy syndrome. More rarely hypoxemia in upright position (platypnea-orthodeoxia syndrome, POS) after pneumonectomy can result from re-opening of an atrial right-to-left shunt through a patent foramen ovale (PFO) due to mediastinal distorsion. Review of literature also shows a unique report of pulmonary veins stenosis resulting in POS without intracardiac shunt after pneumonectomy. Methods: We report the case of a 32-year-old woman who presented POS 6 months after right pneumonectomy for destroyed lung post tuberculosis. Results: The patient described severe dyspnea disappearing when lying. SpO2 decreased from 94% when lying to 60% sitting. Transthoracic echocardiography (TTE) suspected a possible PFO. We first tried to highlight clinical repercussions of PFO by noninvasive exams. Hyperoxia shunt quantification was not tolerated because of increased dyspnea in sitting position. Contrast bubbles TTE was difficult because of the important mediastinal shift but identified only rare left heart bubbles with/without Valsalva both in lying and sitting position, excluding a significant right-to-left shunt. A lung perfusion scintigraphy (injection while sitting) confirmed the absence of systemic isotope uptake. Computed tomographic pulmonary angiography (angio-CT) revealed a stretched but not stenosed left main bronchus, while the shift of the heart into the right cavity was major. Pulmonary angiography did not show embolism but revealed compression of the inferior vena cava (IVC) with impaired venous return to the right heart, as well as compression of the left pulmonary veins. There was no arteriovenous shunt. Cardiac MRI showed torsion of IVC at the level of the diaphragm, and strong atrial contraction contributing to a passive filling of the RV, while the right ventricle was normal. Right catheterism showed major hemodynamic disturbances with negative diastolic pressure in right heart cavities (atrium -12 mm Hg ventricle pressure -7 mm Hg). SaO2 measured in the pulmonary artery decreased from 58% when lying to 45% sitting. Conclusion: We described here an exceedingly rare and complex mechanism explaining POS after right pneumonectomy. Mediastinal repositioning with a silicone breast implant of appropriate size has been scheduled.

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Objectives: Epidemiological studies suggest that adverse events in utero may predispose to premature cardiovascular disease in adulthood, but the mechanisms are not known. Recently, we found that young apparently healthy offspring of mothers with preeclampsia (PE) display systemic endothelial dysfunction. This problem could be related to PE per se or to a genetic abnormality that predisposes the mother to PE and the offspring to vascular dysfunction. To distinguish between these two possibilities, we assessed vascular function in offspring of PE, their siblings who were born after a normal pregnancy, and in control subjects.Methods: We measured endothelium-dependent vasodilation (flow-mediated vasodilation, FMD), in 10 pairs of healthy normotensive siblings, one born after PE (age 15±6 y; mean±SD), the other after normal pregnancy (17±6y) and in 17 (16±7y) controls. All subjects were born at term.Results: The vascular function in siblings of PE who were born after normal pregnancy was normal and comparable to the one in controls (8.6±1.5% vs. 8.1±1.3%, P=0.32), whereas offspring of PE displayed a roughly 30% smaller FMD than the two other groups (5.9±1.6%, P<0.005 vs. both siblings and controls, Figure). The endothelial dysfunction in the offspring of PE was not related to a difference in the central arterial blood pressure or arterial oxygen saturation, because they were comparable in the 3 groups. Figure 1. FMD in the three groups.Conclusions: These findings provide the first evidence that vascular dysfunction in offspring of PE is caused by PE itself, rather than by a genetic abnormality that predisposes the mother to PE and the offspring to a vascular defect. Prevention of PE and/or its successful treatment is expected to prevent vascular dysfunction and premature cardiovascular morbidity and mortality in the offspring.

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Nos últimos anos, a presença reduzida de negros no ensino superior tem ocupado um espaço cada vez mais expressivo nas discussões das agendas de políticas públicas, do movimento social e da academia. Este trabalho busca estudar se e de que forma as mudanças observadas no perfil dos estudantes de graduação se alteraram nos últimos anos. Para tanto, utilizam-se os microdados dos Censos Demográficos de 2000 e 2010 para a construção do perfil do alunado que frequenta cursos de graduação com uma análise complementar de suas diferentes áreas de formação. As análises indicam uma melhora nas taxas de acesso à graduação para os negros, porém com resultados ainda distantes de sua participação no total da população brasileira. O trabalho apresenta o Índice de Paridade Racial - IPR - como um indicador sintético da distância entre negros e brancos nos diferentes aspectos apresentados.

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Percutaneous transluminal angioplasty is frequently used in patients with severe arterial narrowing due to atherosclerosis. However, it induces severe arterial injury and an inflammatory response leading to restenosis. Here, we studied a potential activation of the endocannabinoid system and the effect of FA amide hydrolase (FAAH) deficiency, the major enzyme responsible for endocannabinoid anandamide degradation, in arterial injury. We performed carotid balloon injury in atherosclerosis-prone apoE knockout (apoE(-/-)) and apoE(-/-)FAAH(-/-) mice. Anandamide levels were systemically elevated in apoE(-/-) mice after balloon injury. ApoE(-/-)FAAH(-/-) mice had significantly higher baseline anandamide levels and enhanced neointima formation compared with apoE(-/-) controls. The latter effect was inhibited by treatment with CB1 antagonist AM281. Similarly, apoE(-/-) mice treated with AM281 had reduced neointimal areas, reduced lesional vascular smooth-muscle cell (SMC) content, and proliferating cell counts. The lesional macrophage content was unchanged. In vitro proliferation rates were significantly reduced in CB1(-/-) SMCs or when treating apoE(-/-) or apoE(-/-)FAAH(-/-) SMCs with AM281. Macrophage in vitro adhesion and migration were marginally affected by CB1 deficiency. Reendothelialization was not inhibited by treatment with AM281. In conclusion, endogenous CB1 activation contributes to vascular SMC proliferation and neointima formation in response to arterial injury.

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In recent years, several vasopressin antagonists have been developed that block V-1 receptors either selectively or nonselectively.(1,2) To date, one combined V-1/V-2 antagonist (primarily a V-2 antagonist, as determined on the basis of human receptor binding data), conivaptan, has been approved for the treatment of euvolemic hyponatremia.(3,4) We have previously shown that the vascular properties of a vasopressin V-1 antagonist can be investigated safely and reliably in healthy subjects. We used the measurement of skin blood flow after intradermic injection of exogenous arginine vasopressin on a skin area prevasodilated with calcitonin gene-related peptide (CGRP).(3,5) This technique enables the documentation of the dose-dependent effects of vasopressin or vasopressin antagonists. In this study, we have characterized the V-1a pharmacodynamic profile of increasing doses of RWJ-676070, a new orally active dual V-1a/V-2 receptor antagonist, in healthy subjects.(5)

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O direito à informação no contexto da trajetória dos direitos humanos. Considerações em torno das especificidades do direito à informação, especialmente no que se refere ao direito à informação arquivística e suas características. Aspectos das questões relativas ao acesso aos arquivos públicos.

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Avalia os resultados da capacitação de usuários em buscas informatizadas, por meio do Curso de Acesso às Bases em cd-rom Medline e Lilacs, modalidade do Programa Educativo da Biblioteca/CIR da Faculdade de Saúde Publica da USP, oferecido a docentes e alunos da pós-graduação em saúde pública. O universo de estudo foi constituído de 92 participantes entre 1993 e 1995. Os resultados mostraram que, após a participação no Curso, 65,2% deles conseguiram autonomia no uso das bases de dados, 15,2% solicitaram buscas intermediadas pelo bibliotecário, bem como 19,6% não realizaram forma alguma de busca nas bases da Biblioteca. A intermediação dos bibliotecários foi solicitada por motivos como: pouca familiaridade com as bases, dificuldade em lidar com tecnologia, confiança na busca realizada pelo bibliotecário e falta de tempo para buscas. O egresso do curso que não realizou busca informatizada alegou não ter tido necessidade de fazê-lo no período estudado.

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O presente trabalho visa a mostrar o uso e o diferencial de competitividade que a Tecnologia de Informação (TI) vem trazendo à área de pesquisa e desenvolvimento no Estado de Santa Catarina. A questão fundamental nesta era de domínio da TI está em padronizar sistemas incompatíveis transformando o fluxo da informação em um processo "sem costuras" e transparente. Este estudo, de caráter exploratório, teve como foco identificar usos estratégicos da TI e o diferencial competitivo decorrente destes usos em algumas organizações que desenvolvem pesquisa e desenvolvimento. Procedeu-se ao levantamento de informações por meio de entrevista semi-estruturada junto a cinco grupos de pesquisa e desenvolvimento da Embraco, Epagri e UFSC. Os resultados da pesquisa, em linhas gerais, constataram a obtenção de diferencial competitivo com o uso da tecnologia da informação. Contribui também com estes resultados a forma como se articulam nestas organizações o planejamento, a capacitação contínua de seus funcionários. O diferencial competitivo obtido com o uso de TI nas organizações pesquisadas reflete, de maneira geral, uma nova forma de conectar pessoas e processos, pelo redesenho de funções e ambientes dentro e fora das organizações. Marcadas por uma visão estratégica e por uma estrutura organizacional adequada a esta visão, estas organizações, com o uso da TI, estão contribuindo para o novo cenário mundial da pesquisa e dos negócios.

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Discute a crise dos paradigmas no contexto da sociedade industrial e as repercussões provocadas na sociedade do conhecimento, bem como a dicotomia que o conhecimento traz no seu bojo como fator de dominação e/ou de emancipação. Reconhece que os recursos das novas tecnologias potencializam o acesso e a disponibilização da informação. Conclui, destacando o papel das bibliotecas nesse cenário.

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Descreve as opções tecnológicas e metodológicas para atingir a interoperabilidade no acesso a recursos informacionais eletrônicos, disponíveis na Internet, no âmbito do projeto da Biblioteca Digital Brasileira em Ciência e Tecnologia, desenvolvido pelo Instituto Brasileiro de Informação em Ciência e Tecnologia (IBICT). Destaca o impacto da Internet sobre as formas de publicação e comunicação em C&T e sobre os sistemas de informação e bibliotecas. São explicitados os objetivos do projeto da BDB de fomentar mecanismos de publicação pela comunidade brasileira de C&T, de textos completos diretamente na Internet, sob a forma teses, artigos de periódicos, trabalhos em congressos, literatura "cinzenta", ampliando sua visibilidade e acessibilidade nacional e internacional, e também de possibilitar a interoperabilidade entre estes recursos informacionais brasileiros em C&T, heterogêneos e distribuídos, através de acesso unificado via um portal, sem a necessidade de o usuário navegar e consultar cada recurso individualmente.