7,272 research outputs found

    Filling pressures and collagen metabolism in hypertensive patients with heart failure and normal ejection fraction

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    This study was designed to evaluate the association between circulating biomarkers of collagen metabolism and elevated left-sided filling pressures (FPs), as assessed from elevated estimated pulmonary capillary wedge pressure (ePCWP), in hypertensive patients with heart failure with normal ejection fraction. Echocardiography was performed and ePCWP was calculated from the formula ePCWP=1.90+1.24(maximum early transmitral flow velocity in diastole:tissue Doppler early mitral annulus velocity). The biomarkers of collagen synthesis (carboxy-terminal propeptide of procollagen type I) and degradation (matrix metalloproteinase [MMP] 1 and tissue inhibitor of MMP-1 [TIMP-1]) were analyzed by ELISA methods. Seventy-eight patients with normal FPs (ePCWP 15 mm Hg) were included. Compared with controls, the levels of the 3 biomarkers were increased in the 2 groups of patients. The MMP-1:TIMP-1 ratio, an index of MMP-1 activity, was increased in patients with normal FPs and unchanged in patients with elevated FPs. Patients with elevated FPs exhibited higher TIMP-1 levels and a lower MMP-1:TIMP-1 ratio than patients with normal FPs. ePCWP was independently associated with TIMP-1 (r=0.349; P<0.001) and the MMP-1:TIMP-1 ratio (r=-0.240; P<0.01) in all of the patients. Receiver operating characteristic curves showed that a cutoff value of TIMP-1 of 1557 ng/mL provided 64% sensitivity and 67% specificity for predicting elevated FPs with a relative risk of 3.71 (95% CI: 1.91 to 7.22). These findings suggest that, in hypertensive patients with heart failure with normal ejection fraction and elevated FPs, collagen synthesis predominates over degradation because of a relative excess of TIMP-1. This imbalance can facilitate myocardial fibrosis, which, in turn, may contribute to the elevation of FPs in these patients

    Challenges in the COVID-19 vaccination era: Prioritization of vaccines among essential workers in Mexico

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    The coronavirus disease-2019 (COVID-19) pandemic gave rise to a massive global health concern that has placed an unprecedented strain on healthcare systems, education and economy. The recent vaccine roll-out gave humanity a glimpse of hope. However, more than 50% of the vaccine supply has been acquired by high-income countries, forcing low- and middle-income countries to prioritize who should be vaccinated. In Mexico, the first phase of the vaccination program prioritized healthcare personnel working in front-line COVID-19 public institutions. The second phase was planned for the remaining healthcare workers attending at both COVID and non-COVID areas. The government, however, aiming to reopen schools, decided to vaccinate teachers instead. This raised several concerns, since Mexico tops the ranking of deaths among healthcare workers due to COVID-19 worldwide. Furthermore, the possible framing of vaccines as a political tool has caused commotion among the Mexican people and media, especially since 2021 is the Midterm Election year in Mexico, and the Teachers’ Union has historically played an essential role in this matter. Therefore, it is relevant to share the vaccination experience in resource-constrained settings to provide help and advice to reach an optimal strategy and deflate this pandemic

    Influence of Salix babylonica extract addition on in vitro rumen gas production and degradability of ryegrass silage harvested in different cutting days

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    Four cutoffs of ryegrass after 15 days (CD15), 30 days (CD30), 45 days (CD45), and 60 days (CD60) with Salix babylonica (SB) extract at 0, 30, and 60 ml/kg ryegrass silage were ensiled for 40 days and then evaluated for the in vitro dry matter (DM) digestibility and gas production (GP). No interactions occurred between cutting day and SB extract for silage’s nutrient contents and in vitro GP. The DM and organic matter (OM) contents were decreased linearly with decreased crude protein (CP), neutral detergent fibres, acid detergent fibres, and acid detergent lignin contents with advancing of days. In contrary, addition of SB extract increased silages’ OM and decreased CP contents. Addition of SB extract for CD15 and CD60 silages, quadratically decreased the lag time. However, SB extract increased the rate of GP and GP during the first 12 h of incubation at the level of 30 ml/kg with CD30 silage and asymptotic GP with the level 60 ml/kg of CD60 silage. Increased DM degradability (DMD) of CD30 and CD60 silages versus decreased DMD with CD15 with increased relative GP (ml gas/g DMD). It could be concluded that CD15 had the highest DM and OM content; however, higher GP was noted with CD45 and CD60. SB extract had weak effects on nutrient content and GP, and the level of 30 ml/kg DM was more effective than the level of 60 ml/kg DM

    Performance of the Extensive Air Shower Array at the Uni- versity of Puebla

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    Abstract We report on the performance of the EAS-UAP extensive air shower array after one year of operation. The array is located at 19N 90W, 800 g/cm 2 ; it was designed to measure the energy and arrival direction of primary cosmic rays with energies in the range of 10 14 to 10 16 eV. The array consists of 12 liquid scintillation detectors of 1m 2 effective area distributed in a square grid of 20m that measure the lateral distribution function of the electromagnetic component and 3 large water Cherenkov detectors to help improve the measurement of the time profile of the signals

    The Large Aperture GRB Observatory

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    The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in arrays of Water Cherenkov Detectors (WCD) in high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). WCD at high altitude offer a unique possibility of detecting low gamma fluxes in the 10 GeV - 1 TeV range. The status of the Observatory and data collected from 2007 to date will be presented.Comment: 4 pages, proceeding of 31st ICRC 200

    Water Cherenkov Detectors response to a Gamma Ray Burst in the Large Aperture GRB Observatory

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    In order to characterise the behaviour of Water Cherenkov Detectors (WCD) under a sudden increase of 1 GeV - 1 TeV background photons from a Gamma Ray Burst (GRB), simulations were conducted and compared to data acquired by the WCD of the Large Aperture GRB Observatory (LAGO). The LAGO operates arrays of WCD at high altitude to detect GRBs using the single particle technique. The LAGO sensitivity to GRBs is derived from the reported simulations of the gamma initiated particle showers in the atmosphere and the WCD response to secondaries.Comment: 5 pages, proceeding of the 31st ICRC 200
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