. Therapeutic hypercapnia prevents chronic hypoxia-induced pulmonary hypertension in the newborn rat. Am J Physiol Lung Cell Mol Physiol 291: L912-L922, 2006. First published July 7, 2006 doi:10.1152/ajplung.00480.2005.-Induction of hypercapnia by breathing high concentrations of carbon dioxide (CO2) may have beneficial effects on the pulmonary circulation. We tested the hypothesis that exposure to CO2 would protect against chronic pulmonary hypertension in newborn rats. Atmospheric CO2 was maintained at Ͻ0.5% (normocapnia), 5.5%, or 10% during exposure from birth for 14 days to normoxia (21% O2) or moderate hypoxia (13% O2). Pulmonary vascular and hemodynamic abnormalities in animals exposed to chronic hypoxia included increased pulmonary arterial resistance, right ventricular hypertrophy and dysfunction, medial thickening of pulmonary resistance arteries, and distal arterial muscularization. Exposure to 10% CO2 (but not to 5.5% CO2) significantly attenuated pulmonary vascular remodeling and increased pulmonary arterial resistance in hypoxia-exposed animals (P Ͻ 0.05), whereas both concentrations of CO2 normalized right ventricular performance. Exposure to 10% CO2 attenuated increased oxidant stress induced by hypoxia, as quantified by 8-isoprostane content in the lung, and prevented upregulation of endothelin-1, a critical mediator of pulmonary vascular remodeling. We conclude that hypercapnic acidosis has beneficial effects on pulmonary hypertension and vascular remodeling induced by chronic hypoxia, which we speculate derives from antioxidant properties of CO2 on the lung and consequent modulating effects on the endothelin pathway. carbon dioxide; endothelin; oxidant stress; 8-isoprostane; echocardiography PULMONARY HYPERTENSION, characterized by increased pulmonary artery resistance and pressure, is a common complication of sick newborn infants that carries a high mortality and is associated with considerable long-term morbidity in survivors (43,59,60). Studies suggest that the newborn is uniquely susceptible to remodeling of pulmonary resistance arteries (49). Vascular remodeling contributes to increased resistance (15), may limit the effectiveness of vasodilator therapies (15,32), and in the newborn appears to contribute to inhibition of lung growth and alveolar development (33,45,46,57). Reversal of pathological changes in the newborn pulmonary vascular bed is also more likely to be delayed and incomplete (29,31,49), leading to an increased susceptibility to the development of more severe pulmonary hypertension in later life (10, 17). Thus therapies aimed at preventing or ameliorating vascular remodeling in the newborn have great potential to improve mortality and long-term outcome.A major pathological role for reactive oxygen species (ROS) in pulmonary hypertension is likely, as evidenced by observational studies showing increased oxidant stress in the lungs of adult humans with idiopathic pulmonary arterial hypertension (6, 13) and by the reported efficacy of various antioxidant interventions in the pr...

Pulmonary hypertension (PHT) in neonates is often refractory to the current best therapy, inhaled nitric oxide (NO). The utility of a new class of pulmonary vasodilators, Rho-kinase (ROCK) inhibitors, has not been examined in neonatal animals. Our objective was to examine the activity and expression of RhoA/ROCK in normal and injured pulmonary arteries and to determine the short-term pulmonary hemodynamic (assessed by pulse wave Doppler) effects of ROCK inhibitors (15 mg/kg ip Y-27632 or 30 mg/kg ip fasudil) in two neonatal rat models of chronic PHT with pulmonary vascular remodeling (chronic hypoxia, 0.13 Fi(O(2)), or 1 mg.kg(-1).day(-1) ip chronic bleomycin for 14 days from birth). Activity of the RhoA/ROCK pathway and ROCK expression were increased in hypoxia- and bleomycin-induced PHT. In both models, severe PHT [characterized by raised pulmonary vascular resistance (PVR) and impaired right ventricular (RV) performance] did not respond acutely to inhaled NO (20 ppm for 15 min) or to a single bolus of a NO donor, 3-morpholinosydnonimine hydrochloride (SIN-1; 2 mug/kg ip). In contrast, a single intraperitoneal bolus of either ROCK inhibitor (Y-27632 or fasudil) completely normalized PVR but had no acute effect on RV performance. ROCK-mediated vasoconstriction appears to play a key role in chronic PHT in our two neonatal rat models. Inhibitors of ROCK have potential as a testable therapy in neonates with PHT that is refractory to NO.

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Failure of ductal closure is common in extremely low birth weight infants with significant postnatal morbidities from both pulmonary overcirculation (i.e. chronic lung disease) and/or systemic hypoperfusion (i.e. necrotizing enterocolitis). Early clinical signs of a hemodymanically significant ductus may be non-specific (i.e. hypotension, increasing ventilator requirements, metabolic acidosis) necessitating early screening by echocardiography. Cyclooxygenase inhibitors remain the first-line treatment option. Indomethacin remains the most commonly used agent, despite comparable efficacy and reduced risk of adverse events with ibuprofen. Surgical intervention is recommended after failure of medical therapy, contraindications to medical treatment or fulminating duct-related cardiorespiratory deterioration. Wherever possible, surgical intervention in ELBW infants should be avoided in the first week of life due to the potential risks of ischemia-reperfusion cerebral hemorrhage. The postoperative course is often complicated by left ventricular failure, pulmonary edema, and/or hemodynamic instability requiring close monitoring and physiologically relevant therapeutic interventions.

Failure of ductal closure is common in extremely low birth weight infants with significant postnatal morbidities from both pulmonary overcirculation (i.e. chronic lung disease) and/or systemic hypoperfusion (i.e. necrotizing enterocolitis). Early clinical signs of a hemodymanically significant ductus may be non‐specific (i.e. hypotension, increasing ventilator requirements, metabolic acidosis) necessitating early screening by echocardiography. Cyclooxygenase inhibitors remain the first‐line treatment option. Indomethacin remains the most commonly used agent, despite comparable efficacy and reduced risk of adverse events with ibuprofen. Surgical intervention is recommended after failure of medical therapy, contraindications to medical treatment or fulminating duct‐related cardiorespiratory deterioration. Wherever possible, surgical intervention in ELBW infants should be avoided in the first week of life due to the potential risks of ischemia‐reperfusion cerebral hemorrhage. The postoperative course is often complicated by left ventricular failure, pulmonary edema, and/or hemodynamic instability requiring close monitoring and physiologically relevant therapeutic interventions.

Este artigo tem como objetivo investigar a formação de pesquisadores em um grupo de pesquisa em Educação em Ciências e Matemática. O corpus foi constituído por "memórias", uma metodologia de coleta de dados desenvolvida por membros do grupo. Em analogia com os focos da aprendizagem científica, construímos os focos da aprendizagem para a pesquisa (FAP) que articulam essa aprendizagem por meio de seis eixos: (1) Interesse; (2) Conhecimento; (3) Metodologia; (4) Criatividade; (5) Comunidade; (6) Identidade. Para análise dos dados, adotamos os procedimentos metodológicos da Análise Textual Discursiva. Concluímos que as discussões realizadas nas reuniões do grupo têm lidado, sobretudo, com: as questões metodológicas, as ligações entre os referenciais teóricos e os dados, e a divulgação de resultados de pesquisa em diferentes comunidades de pesquisa. Estes resultados podem ser interpretados como uma mudança nos discursos dos sujeitos de uma investigação orientada para uma investigação autônoma

RESUMO: Objetivou-se determinar a frequência de consumo de pescado na cidade de Belo Horizonte e determinar principais locais de aquisição e consumo do produto. Para tanto, foram entrevistadas 396 pessoas através de um formulário contendo onze perguntas. Os dados obtidos foram tabulados em software de edição de planilha eletrônica e gráficos gerados. A carne de peixe é a menos consumida na cidade de Belo Horizonte. A frequência de consumo foi duas ou mais vezes ao mês (25,3%). O principal local de consumo foi a residência dos entrevistados (80,3%) e os supermercados foram determinados como o local de maior aquisição (71,5%).Palavras-chave: peixe, derivados de peixe, hábito de consumo. CONSUMPTION PROFILE OF FISH IN BELO HORIZONTE, MGABSTRACT: The aim of this study was to determine the frequency of consumption of fish flesh and derivatives in Belo Horizonte's city, to determine the major sites of acquisition and consumption of the product. The hundred ninety six people were interviewed through a quiz containing eleven questions. Data were tabulated in editing software spreadsheet and graphics generated. Fish is the least meat consumed less in Belo Horizonte's city. The frequency of consumption was two or more times a month (25,3%). Homes were the principal place of consumption (80,3%), and supermarkets were determined as site of largest acquisition (71,5%).