125 research outputs found

    Upregulation of Hemoglobin Expression by Oxidative Stress in Hepatocytes and Its Implication in Nonalcoholic Steatohepatitis

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    Recent studies revealed that hemoglobin is expressed in some non-erythrocytes and it suppresses oxidative stress when overexpressed. Oxidative stress plays a critical role in the pathogenesis of non-alcoholic steatohepatitis (NASH). This study was designed to investigate whether hemoglobin is expressed in hepatocytes and how it is related to oxidative stress in NASH patients. Analysis of microarray gene expression data revealed a significant increase in the expression of hemoglobin alpha (HBA1) and beta (HBB) in liver biopsies from NASH patients. Increased hemoglobin expression in NASH was validated by quantitative real time PCR. However, the expression of hematopoietic transcriptional factors and erythrocyte specific marker genes were not increased, indicating that increased hemoglobin expression in NASH was not from erythropoiesis, but could result from increased expression in hepatocytes. Immunofluorescence staining demonstrated positive HBA1 and HBB expression in the hepatocytes of NASH livers. Hemoglobin expression was also observed in human hepatocellular carcinoma HepG2 cell line. Furthermore, treatment with hydrogen peroxide, a known oxidative stress inducer, increased HBA1 and HBB expression in HepG2 and HEK293 cells. Importantly, hemoglobin overexpression suppressed oxidative stress in HepG2 cells. We concluded that hemoglobin is expressed by hepatocytes and oxidative stress upregulates its expression. Suppression of oxidative stress by hemoglobin could be a mechanism to protect hepatocytes from oxidative damage in NASH

    Retreat into scientism, paradoxes of transparency, and corruption in education

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    Um dos sintomas da razĂŁo indolente (SANTOS, 2006) Ă© o recuo ao cientificismo, o qual tem sido, particularmente, acentuado nas polĂ­ticas, cada vez mais hegemĂŽnicas, de avaliação, de prestação de contas e de responsabilização. Por isso, um dos objetivos deste texto Ă© o de colocar em causa este aparente consenso cientificista (ou este consenso supostamente transideolĂłgico) e fazer uma breve incursĂŁo exploratĂłria ao que aqui se designa de paradoxos da transparĂȘncia. Considera-se que esses paradoxos traduzem a existĂȘncia de tensĂ”es e contradiçÔes relativas a uma dimensĂŁo central dos discursos polĂ­ticos e educacionais contemporĂąneos. Com isso, o artigo pretende dar continuidade a uma linha de pesquisa que tem procurado sublinhar a relevĂąncia da necessidade de complexificar e dar maior rigor teĂłrico-conceptual Ă  accountability em educação. Finalmente, tentando abrir caminho para o desenvolvimento de novas articulaçÔes e anĂĄlises, chama-se a atenção para a corrupção na educação cuja complexidade ainda Ă© insuficientemente conhecida e pesquisada, nomeadamente, nas suas relaçÔes com as problemĂĄticas da transparĂȘncia e da accountability. Admite-se que as prĂĄticas de corrupção em educação, em muitas situaçÔes, sĂŁo (paradoxalmente) induzidas pela necessidade de dar resposta Ă  governação baseada nos nĂșmeros, nos rankings e nas (supostas) evidĂȘncias, anulando completamente as expectativas legĂ­timas em torno da transparĂȘncia dos processos educacionais e das decisĂ”es polĂ­ticas.One symptom of “indolent reason” (SANTOS, 2006) is the retreat into scientism, which is especially marked in the increasingly hegemonic policies surrounding assessment, reporting and accountability. As such, one of the aims of this paper is to call into question this apparent consensus on scientism (a supposedly trans-ideological consensus), and briefly explore what we define as the paradoxes of transparency. These paradoxes are found to reveal the existence of tensions and contradictions concerning a central aspect of current political and educational discourse. In doing so, the article seeks to continue a line of study which has aimed to emphasize the significance of the need for a more complex, and theoretically and conceptually rigorous understanding of accountability in education. Finally, in an attempt to pave the way for further discussion and analysis, attention is drawn to corruption in education, the complex nature of which remains insufficiently understood and studied, notably in terms of its relationship with the problems of transparency and accountability. It is acknowledged that practices of corruption within education are, in many situations, (paradoxically) caused by the need to answer to a system of governance based on numbers, league tables, and (supposed) truths, completely nullifying legitimate expectations about the transparency of educational processes and policy decisions.Trabalho financiado por Fundos Nacionais atravĂ©s da FCT – Fundação para a CiĂȘncia e a Tecnologia – no Ăąmbito do Projeto PEst-OE/CED/UI1661/2014.info:eu-repo/semantics/publishedVersio

    Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls.

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    Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls' STEM participation

    Integrated high-content quantification of intracellular ROS levels and mitochondrial morphofunction

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    Oxidative stress arises from an imbalance between the production of reactive oxygen species (ROS) and their removal by cellular antioxidant systems. Especially under pathological conditions, mitochondria constitute a relevant source of cellular ROS. These organelles harbor the electron transport chain, bringing electrons in close vicinity to molecular oxygen. Although a full understanding is still lacking, intracellular ROS generation and mitochondrial function are also linked to changes in mitochondrial morphology. To study the intricate relationships between the different factors that govern cellular redox balance in living cells, we have developed a high-contentmicroscopy-based strategy for simultaneous quantification of intracellular ROS levels and mitochondrial morphofunction. Here, we summarize the principles of intracellular ROS generation and removal, and we explain the major considerations for performing quantitative microscopy analyses of ROS and mitochondrial morphofunction in living cells. Next, we describe our workflow, and finally, we illustrate that a multiparametric readout enables the unambiguous classification of chemically perturbed cells as well as laminopathy patient cells

    Knowledge actors and the construction of new governing panoramas:The case of the European Commission’s DG Education and Culture

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    RESUMO: Este artigo aborda o tema da governança da educação na Europa. Esse espaço da polĂ­tica tem sido dominado por grandes interesses e organizaçÔes transnacionais, entre as quais se destacam a Organização para a Cooperação e Desenvolvimento EconĂŽmico (OCDE) e a ComissĂŁo Europeia (CE). Este artigo procura explorar e explicar quais sĂŁo os efeitos constitutivos que as prĂĄticas sistemĂĄticas de 'medição' e de estandardização tĂȘm na intensificação da convergĂȘncia entre a Direção-Geral de Educação e Cultura da CE e a OCDE, a qual, por meio do PISA e de outros testes internacionais, tornou-se um ator influente na polĂ­tica educativa em uma escala global. O artigo pretende identificar os feitos do 'governo pelos nĂșmeros' nas interdependĂȘncias criadas entre as duas organizaçÔes internacionais
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