51 research outputs found

    Vitamin E-analog Trolox prevents endoplasmic reticulum stress in frozen-thawed ovarian tissue of capuchin monkey (Sapajus apella)

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    Ovarian fragments were exposed to 0.5 M sucrose and 1 M ethylene glycol (freezing solution; FS) with or without selenium or Trolox. Histological and ultrastructural analyses showed that the percentages of normal follicles in control tissue and in tissue after exposure to FS+50 μM Trolox were similar. Trolox prevented endoplasmic reticulum (ER)-related vacuolization, which is commonly observed in oocytes and stromal tissue after exposure to FS. From the evaluated stress markers, superoxide dismutase 1 (SOD1) was up-regulated in ovarian tissue exposed to FS+10 ng/ml selenium. Ovarian fragments were subsequently frozenthawed in the presence of FS with or without 50 μM Trolox, followed by in vitro culture (IVC). Antioxidant capacity in ovarian fragments decreased after freeze-thawing in Troloxfree FS compared with FS+50 μMTrolox. Although freezing itself minimized the percentage of viable follicles in each solution, Trolox supplementation resulted in higher rates of viable follicles (67 %), even after IVC (61 %). Furthermore, stress markers SOD1 and ERp29 were up-regulated in ovarian tissue frozen-thawed in Trolox-free medium. Relative mRNA expression of growth factors markers was evaluated after freeze-thawing followed by IVC. BMP4, BMP5, CTGF, GDF9 and KL were down-regulated independently of the presence of Trolox in FS but down-regulation was less pronounced in the presence of Trolox. Thus, medium supplementation with 50 μMTrolox prevents ER stress and, consequently, protects ovarian tissue from ER-derived cytoplasmic vacuolization. ERp29 but not ERp60, appears to be a key marker linking stress caused by freezing-thawing and cell vacuolization.http://link.springer.com/journal/441hb201

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true

    Gaseous phase heat capacity of benzoic acid

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    The gaseous phase heat capacity of benzoic acid (BA) was proven using the experimental technique called the "in vacuum sublimation/vaporization Calvet microcalorimetry drop method". To overcome known experimental shortfalls, the gaseous phase heat capacity of BA monomer was estimated by ab initio calculations and compared with experimental results. Gaseous phase heat capacities of BA were directly derived via calculated harmonic frequencies obtained by density functional theory (DFT) (B3LYP, BLYP, BP86, with 6-311++G(d,p), TZVP, cc-pVTZ basis sets) and the second-order Møller-Plesset theory, MP2/6-311++G(d,p). To increase the accuracy of estimation of the thermal properties, a procedure based on the calculation of the heat capacity from quantum chemical calculations in combination with a heat capacity balance of isodesmic reactions is described and applied to calculate the gaseous phase heat capacity, Cp,m, of the monomeric species over the temperature range of (298.15 to 600) K. The gaseous phase thermodynamic properties of the monomeric form of the BA were also derived from the assignment of the fundamental vibrational frequencies using experimental IR spectra. An excellent agreement among the experimental gaseous phase heat capacities, the results obtained using the proposed ab initio procedure, and the results derived from the assignment of fundamental vibrational frequencies was found. The results for the monomeric form of the BA, directly or indirectly obtained, and conclusions of this work strongly support the thesis that the gaseous phase heat capacity data as currently found in the literature are underestimated to the order of 20 %

    Experimental Characterization of Hydrogen Trapping on API 5CT P110 Steel. Part. I: Effect on Hydrogen Embrittlement Susceptibility

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    Hydrogen permeation tests and tensile mechanical tests were performed at room temperature on API 5CT P110 steel to characterize hydrogen trapping and to evaluate their hydrogen embrittlement susceptibility. The hydrogen trap density was calculated from two consecutive hydrogen permeation transients plotted using an electrochemical cell. Slow strain rate tensile tests on hydrogen-charged samples through cathodic polarization at different potentials were performed to evaluate the hydrogen embrittlement susceptibility. Thereby it was established the lowest potential that characterizes the onset of the cathodic overprotection for studied steel. After mechanical tests was observed a decrease in ductility as the protection potential became more negative and that the fracture mode was changed from ductile microvoid coalescence on the as-received steel to extended quasi-cleavage on the hydrogen-charged steel. The results showed that API 5CT P110 steel has high susceptibility to hydrogen embrittlement conditioned by a predominance of reversible traps in microstructure and by high hydrogen solubility

    New theoretical frontiers for corporate social responsibility: The corporate role in sustainable development of territories [Novas fronteiras teóricas para a responsabilidade social empresarial: O papel das empresas no desenvolvimento sustentável dos territórios]

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    This paper aims to contribute to the construction of new theoretical frameworks in critical bases on corporate responsibility in the sustainable development of territories. For this, we present at first the approaches of New Economic Sociology as a way to reflect about the development beyond the pure economic perspective. In a second step, we discuss the contradictions of sustainable development concepts and the implications of its institutionalization. Then we investigate some approaches on corporate social responsibility with focus on a critical discussion on the Theory of Stakeholders which is a very present theory in traditional studies on the role of business in sustainable development of territories

    Determinants of happiness and quality of life in patients with rheumatoid arthritis: A structural equation modelling approach

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    Objectives Besides increasing longevity, the ultimate goal of medical care is to improve patients’ enjoyment of life, a concept akin to happiness. This study examined the determinants of happiness and quality of life (QoL) in patients with rheumatoid arthritis (RA). Methods In this observational, cross-sectional study, patients were assessed on disease activity, disease impact, personality, QoL and happiness. Structural equation modelling estimation was used to analyse the associations between these dimensions, pursuing three hypotheses: H1—disease activity and perceived impact of disease are negatively associated with overall QoL and happiness in patients with RA; H2—‘positive’ personality traits are related to happiness both directly and indirectly through perceived disease impact; H3—happiness has a mediating effect in the relation between impact of disease and QoL. Results Data from 213 patients were analysed. Results supported all driving hypotheses. Happiness was positively related to ‘positive’ personality and, to a lesser extent, negatively related to impact of disease. Impact of disease, in turn, was positively related to disease activity and mitigated by ‘positive’ personality traits. Impact of disease had a much stronger relation with QoL than with happiness. Happiness mitigated the negative effect of disease impact on QoL. Conclusion Optimisation of QoL and happiness of people with RA requires effective control of the disease process and also improvement of the disease impact domains. Personality seems to play a pivotal mediating role in these relations
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