1,613 research outputs found

    Molecular elucidation of CO2 methanation over a highly active, selective and stable LaNiO3/CeO2-derived catalyst by in situ FTIR and NAP-XPS

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    The CO2 methanation mechanism over the highly active (TOF=75.1 h−1), selective (>92%) and stable 10% LaNiO3/CeO2-derived catalyst is still unresolved. The surface of the catalyst is monitored under hydrogenation (H2), oxidizing (CO2) and CO2 methanation (H2 +CO2) conditions by near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) using synchrotron radiation. Meanwhile, the main reaction intermediates are identified by in situ FTIR analysis. NAP-XPS experiments confirm that LaNiO3 perovskite reduction leads to the ex-solution of Ni0 nanoparticles and Ni2+single bondCeO2−x and Ni2+single bondLa2O3 interfaces conformation, favouring the CO2 adsorption and the H2 dissociation/transfer. In situ FTIR experiments combined with the C1s spectra (NAP-XPS) suggest that the CO2 activation occurs on CeO2−x (oxygen vacancies and OH–) at low temperatures, in the form of bicarbonates; whereas, mono-/bidentate carbonates are formed on different strength La2O3 sites at increasing temperatures. These species are consecutively reduced to formates, as the main reaction intermediate, and methane by the H spilled from Ni0 nanoparticles near to NiOsingle bondCeO2−x and NiOsingle bondLa2O3 interfaces.Support for this study was provided by Projects PID2019–105960RB-C21 and PID2019–105960RB-C22 by MCIN/AEI/10.13039/501100011033, the Basque Government (Project IT1509–2022), Generalitat Valenciana (CIPROM/2021/74) and ALBA synchrotron. One of the authors (JAOC) acknowledges the postdoctoral research grant (DOCREC20/49) provided by the University of the Basque Country (UPV/EHU)

    Monitoring by in situ NAP-XPS of active sites for CO2 methanation on a Ni/CeO2 catalyst

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    Ni/CeO2 catalysts are very active and selective for total hydrogenation of CO2 to methane, but the nature of the active sites is still unclear. The surface of a Ni/CeO2 catalyst has been monitored under CO2 methanation conditions by Near Ambient Pressure-XPS (NAP-XPS) using synchrotron radiation, and has been concluded that the species involved in the redox processes taking place during the CO2 methanation mechanism are the Ni2+-CeO2/Ni0 and Ce4+/Ce3+ pairs. In addition, a small fraction of nickel is present on the catalyst surface forming NiO and Ni2+-carbonates/hydroxyls (around 20% of the total surface nickel), but these species do not participate in the redox processes of the methanation mechanism. Under CO2 methanation conditions the H2 reduction rate of the Ni2+-CeO2/Ni0 and Ce4+/Ce3+ couples is much faster than their CO2 reoxidation rate (2 times faster, at least, at 300ºC), but a certain proportion of nickel always remains oxidized under reaction conditions. The high activity of Ni/CeO2 catalysts for CO2 methanation is tentatively attributed to the simultaneous presence of Ni2+-CeO2 and Ni0 active sites where CO2 and H2 are expected to be efficiently dissociated, respectively.Generalitat Valenciana, Spain (PROMETEO/2018/0765) Ministry for Science and Innovation MICINN, Spain (Projects PID2019-105960RB-C21 and PID2019-105960RB-C22) Junta de Andalucía, Spain (Project P18-RTJ-2974); European Union’s Horizon 2020 Research and Innovation Program (Marie Skłodowska-Curie grant agreement No 713567) Science Foundation Ireland Research Centre, Ireland (award 12/RC/2278_P2) ALBA synchrotron, Spain (Proposal number: ID 2020094556)

    Combining heart rate and systolic blood pressure to improve risk stratification in older patients with heart failure: Findings from the RICA Registry

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    Objectives: Heart rate (HR) and systolic blood pressure (SBP) are independent prognostic variables in patients with heart failure (HF). We evaluated if combining HR and SBP could improve prognostic assessment in older patients. Methods: Variables associated with all-cause mortality and readmission for HF during 9 months of follow-up were analyzed from the Spanish Heart Failure Registry (RICA). HR and SBP values were stratified in three combined groups. Results: We evaluated 1551 patients, 82 years and 56% women. Using HR strata of < 70 and ≥ 70 bpm we found mortality rates of 9.8 and 13.6%, respectively (hazard ratio 1.0 and 1.35). For SBP ≥ 140, 120–140 and < 120 mm Hg, mortality rates were 8.2, 10.4 and 20.3%. respectively (hazard ratio 1.0, 1.34 and 2.76). Using combined strata of HR < 70 bpm and SBP ≥ 140 mm Hg (n = 176; low-risk), HR < 70 and SBP < 140 + HR ≥ 70 and SBP < 120 (n = 1089; moderate-risk) and HR ≥ 70 and SBP < 120 (n = 286; high-risk) we found mortality rates of 4.5%, 11.0% and 24.0%, respectively. Multivariate Cox regression for all-cause mortality shows for low-, middle- and high-risk groups was 1 (reference), 1.93 (95% CI: 0.93–3.99, p = 0.077) and 4.32 (95% CI: 2.04–9.14, p < 0.001). BMI, NYHA, MDRD, hypertension and sodium were also independent prognostic factors. Conclusions: The combination provides better risk discrimination than use of HR and SBP alone and may provide a simple and reliable tool for risk assessment for older HF patients in clinical practice

    Role for Maternal Asthma in Severe Human Metapneumovirus Lung Disease Susceptibility in Children

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    Background: Severity of human metapneumovirus (hMPV) lower respiratory illness (LRTI) is considered similar to that observed for respiratory syncytial virus (RSV). However, differences in severity between these pathogens have been noted, suggesting the degree of illness may vary in different populations. Moreover, a potential association between hMPV and asthma also suggests that hMPV may preferentially affect asthmatic subjects. Methods: In a population-based surveillance study in children aged <2 years admitted for severe LRTI in Argentina, nasopharyngeal aspirates were tested by RT-PCR for hMPV, RSV, influenza A, and human rhinovirus. Results: Of 3947 children, 383 (10%) were infected with hMPV. The hospitalization rate for hMPV LRTI was 2.26 per 1000 children (95% confidence interval [CI], 2.04-2.49). Thirty-nine (10.2%) patients infected with hMPV experienced life-threatening disease (LTD; 0.23 per 1000 children; 95% CI,. 16-.31/1000), and 2 died (mortality rate 0.024 per 1000; 95% CI,. 003-.086). In hMPV-infected children birth to an asthmatic mother was an increased risk for LTD (odds ratio, 4.72; 95% CI, 1.39-16.01). We observed a specific interaction between maternal asthma and hMPV infection affecting risk for LTD. Conclusions: Maternal asthma increases the risk for LTD in children <2 years old hospitalized for severe hMPV LRTI.Fil: Libster, Romina Paula. Fundación para la Investigación en Infectología Infantil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Esteban, Ignacio. Fundación para la Investigación en Infectología Infantil; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Bianchi, Alejandra Silvina. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Alva Grimaldi, Luciano. Gobierno de la Provincia de Buenos Aires. Hospital Zonal General de Agudos Doctor Lucio Melendez.; ArgentinaFil: Dueñas, Karina. Gobierno de la Provincia de Buenos Aires. Hospital Interzonal de Agudos Evita.; ArgentinaFil: Sancillo, Andrea. Gobierno de la Provincia de Buenos Aires. Hospital Interzonal de Agudos Evita.; ArgentinaFil: Rodriguez, Andrea. Gobierno de la Provincia de Buenos Aires. Hospital Provincial Evita Pueblo.; ArgentinaFil: Ferrero, Fernando. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Stein, Katherine. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Acosta, Patricio Leandro. Fundación para la Investigación en Infectología Infantil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ferolla, Fausto Martín. Fundación para la Investigación en Infectología Infantil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bergel, Eduardo. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Caballero, Mauricio Tomás. Fundación para la Investigación en Infectología Infantil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Polack, Fernando Pedro. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Pellegrino, Gustavo. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Fernandez Gago, Guadalupe. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Pozzolo, Cecilia. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Castro, Laura. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Almeida, Rodrigo Egues. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Rebec, Beatriz. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: González, Mariela. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Calvo, Mariel. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Henrichsen, Julieta. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Nocito, Celina. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Barbero, Guillermo. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Ves Losada, Juan. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Bonina, Angel. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Flamenco, Edgardo. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Rodriguez Perez, Alberto. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Kobylarz, Alicia. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Raggio, Mirta. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Schavlosky, Graciela. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Caria, Adriana. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Barboza, Edgar. Fundación para la Investigación en Infectología Infantil; ArgentinaFil: Sastre, Gustavo. Fundación para la Investigación en Infectología Infantil; Argentin

    Strategies to design clinical studies to identify predictive biomarkers in cancer research

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    The discovery of reliable biomarkers to predict efficacy and toxicity of anticancer drugs remains one of the key challenges in cancer research. Despite its relevance, no efficient study designs to identify promising candidate biomarkers have been established. This has led to the proliferation of a myriad of exploratory studies using dissimilar strategies, most of which fail to identify any promising targets and are seldom validated. The lack of a proper methodology also determines that many anti-cancer drugs are developed below their potential, due to failure to identify predictive biomarkers. While some drugs will be systematically administered to many patients who will not benefit from them, leading to unnecessary toxicities and costs, others will never reach registration due to our inability to identify the specific patient population in which they are active. Despite these drawbacks, a limited number of outstanding predictive biomarkers have been successfully identified and validated, and have changed the standard practice of oncology. In this manuscript, a multidisciplinary panel reviews how those key biomarkers were identified and, based on those experiences, proposes a methodological framework—the DESIGN guidelines—to standardize the clinical design of biomarker identification studies and to develop future research in this pivotal field

    A blood microRNA classifier for the prediction of ICU mortality in COVID-19 patients: a multicenter validation study

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    Background: The identification of critically ill COVID-19 patients at risk of fatal outcomes remains a challenge. Here, we first validated candidate microRNAs (miRNAs) as biomarkers for clinical decision-making in critically ill patients. Second, we constructed a blood miRNA classifier for the early prediction of adverse outcomes in the ICU. Methods: This was a multicenter, observational and retrospective/prospective study including 503 critically ill patients admitted to the ICU from 19 hospitals. qPCR assays were performed in plasma samples collected within the first 48 h upon admission. A 16-miRNA panel was designed based on recently published data from our group. Results: Nine miRNAs were validated as biomarkers of all-cause in-ICU mortality in the independent cohort of critically ill patients (FDR < 0.05). Cox regression analysis revealed that low expression levels of eight miRNAs were associated with a higher risk of death (HR from 1.56 to 2.61). LASSO regression for variable selection was used to construct a miRNA classifier. A 4-blood miRNA signature composed of miR-16-5p, miR-192-5p, miR-323a-3p and miR-451a predicts the risk of all-cause in-ICU mortality (HR 2.5). Kaplan‒Meier analysis confirmed these findings. The miRNA signature provides a significant increase in the prognostic capacity of conventional scores, APACHE-II (C-index 0.71, DeLong test p-value 0.055) and SOFA (C-index 0.67, DeLong test p-value 0.001), and a risk model based on clinical predictors (C-index 0.74, DeLong test-p-value 0.035). For 28-day and 90-day mortality, the classifier also improved the prognostic value of APACHE-II, SOFA and the clinical model. The association between the classifier and mortality persisted even after multivariable adjustment. The functional analysis reported biological pathways involved in SARS-CoV infection and inflammatory, fibrotic and transcriptional pathways. Conclusions: A blood miRNA classifier improves the early prediction of fatal outcomes in critically ill COVID-19 patients.11 página

    Epidemiology of surgery associated acute kidney injury (EPIS-AKI): a prospective international observational multi-center clinical study

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    Purpose: The incidence, patient features, risk factors and outcomes of surgery-associated postoperative acute kidney injury (PO-AKI) across different countries and health care systems is unclear. Methods: We conducted an international prospective, observational, multi-center study in 30 countries in patients undergoing major surgery (&gt; 2-h duration and postoperative intensive care unit (ICU) or high dependency unit admission). The primary endpoint was the occurrence of PO-AKI within 72&nbsp;h of surgery defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Secondary endpoints included PO-AKI severity and duration, use of renal replacement therapy (RRT), mortality, and ICU and hospital length of stay. Results: We studied 10,568 patients and 1945 (18.4%) developed PO-AKI (1236 (63.5%) KDIGO stage 1500 (25.7%) KDIGO stage 2209 (10.7%) KDIGO stage 3). In 33.8% PO-AKI was persistent, and 170/1945 (8.7%) of patients with PO-AKI received RRT in the ICU. Patients with PO-AKI had greater ICU (6.3% vs. 0.7%) and hospital (8.6% vs. 1.4%) mortality, and longer ICU (median 2 (Q1-Q3, 1-3) days vs. 3 (Q1-Q3, 1-6) days) and hospital length of stay (median 14 (Q1-Q3, 9-24) days vs. 10 (Q1-Q3, 7-17) days). Risk factors for PO-AKI included older age, comorbidities (hypertension, diabetes, chronic kidney disease), type, duration and urgency of surgery as well as intraoperative vasopressors, and aminoglycosides administration. Conclusion: In a comprehensive multinational study, approximately one in five patients develop PO-AKI after major surgery. Increasing severity of PO-AKI is associated with a progressive increase in adverse outcomes. Our findings indicate that PO-AKI represents a significant burden for health care worldwide

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

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    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

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    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

    Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

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    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity
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