132 research outputs found

    Transition from a Subaerial to a Subnival Permafrost Temperature Regime Following Increased Snow Cover (Livingston Island, Maritime Antarctic)

    Get PDF
    The Antarctic Peninsula (AP) region has been one of the regions on Earth with strongest warming since 1950. However, the northwest of the AP showed a cooling from 2000 to 2015, which had local consequences with an increase in snow accumulation and a deceleration in the loss of mass from glaciers. In this paper, we studied the e ects of increased snow accumulation in the permafrost thermal regime in two boreholes (PG1 and PG2) in Livingston Island, South Shetlands Archipelago, from 2009 to 2015. The two boreholes located c. 300 m apart but at similar elevation showed di erent snow accumulation, with PG2 becoming completely covered with snow all year long, while the other remained mostly snow free during the summer. The analysis of the thermal regimes and of the estimated soil surface energy exchange during the study period showed the e ects of snow insulation in reducing the active layer thickness. These e ects were especially relevant in PG2, which transitioned from a subaerial to a subnival regime. There, permafrost aggraded from below, with the active layer completely disappearing and the e ciency of thermal insulation by the snowpack prevailing in the thermal regime. This situation may be used as an analogue for the transition from a periglacial to a subglacial environment in longer periods of cooling in the paleoenvironmental record.info:eu-repo/semantics/publishedVersio

    LA SELECCIÓN DE VÍAS RACIONALES PARA LA SOLUCIÓN DE PROBLEMAS GEOMÉTRICOS / THE SELECTION OF RATIONAL VÍAS FOR THE SOLUTION OF GEOMETRIC PROBLEMS

    Get PDF
    El análisis y selección de vías racionales para la solución de problemas constituye una necesidad del aprendizaje de la geometría, por el aporte que hace al desarrollo del pensamiento en general y en particular a racionalizar el trabajo mental y al desempeño creativo, es una problemática actual revelada en diferentes escenarios la cual requiere de atención, en este artículo científico se socializa un procedimiento metodológico confeccionado para favorecer el análisis de las vías de solución más racionales, basado en la elaboración de un sistema de ejercicios y problemas de la asignatura Geometría Analítica que tiene en cuenta la redacción del texto para revelar la intensión del mismo, derivado de varios trabajos científicos y metodológicos. Los resultados alcanzados son satisfactorios, demostrando la pertinencia del procedimiento metodológico y su influencia positiva en la elevación del aprendizaje de los estudiantes de pregrado y posgrad

    Activity breaks. Incorporación de los descansos activos en la educación superior

    Get PDF
    Los objetivos iniciales del aumento de la práctica de actividad física para la mejora de la atención y reducción de los hábitos sedentarios, tensión y estrés, se han logrado por medio de la implantación de los descansos activos en las clases teóricas. El uso y diseño de los descansos de entre 5 y 10 minutos, ha conseguido mejorar la atención del alumnado que los ha practicado en la hora siguiente de clase teórica. El proyecto se ha llevado a cabo teniendo un grupo control y uno experimental en el que se han desarrollado los descansos activos

    Human Hereditary Cardiomyopathy Shares a Genetic Substrate With Bicuspid Aortic Valve.

    Get PDF
    The complex genetics underlying human cardiac disease is evidenced by its heterogenous manifestation, multigenic basis, and sporadic occurrence. These features have hampered disease modeling and mechanistic understanding. Here, we show that 2 structural cardiac diseases, left ventricular noncompaction (LVNC) and bicuspid aortic valve, can be caused by a set of inherited heterozygous gene mutations affecting the NOTCH ligand regulator MIB1 (MINDBOMB1) and cosegregating genes. We used CRISPR-Cas9 gene editing to generate mice harboring a nonsense or a missense MIB1 mutation that are both found in LVNC families. We also generated mice separately carrying these MIB1 mutations plus 5 additional cosegregating variants in the ASXL3, APCDD1, TMX3, CEP192, and BCL7A genes identified in these LVNC families by whole exome sequencing. Histological, developmental, and functional analyses of these mouse models were carried out by echocardiography and cardiac magnetic resonance imaging, together with gene expression profiling by RNA sequencing of both selected engineered mouse models and human induced pluripotent stem cell-derived cardiomyocytes. Potential biochemical interactions were assayed in vitro by coimmunoprecipitation and Western blot. Mice homozygous for the MIB1 nonsense mutation did not survive, and the mutation caused LVNC only in heteroallelic combination with a conditional allele inactivated in the myocardium. The heterozygous MIB1 missense allele leads to bicuspid aortic valve in a NOTCH-sensitized genetic background. These data suggest that development of LVNC is influenced by genetic modifiers present in affected families, whereas valve defects are highly sensitive to NOTCH haploinsufficiency. Whole exome sequencing of LVNC families revealed single-nucleotide gene variants of ASXL3, APCDD1, TMX3, CEP192, and BCL7A cosegregating with the MIB1 mutations and LVNC. In experiments with mice harboring the orthologous variants on the corresponding Mib1 backgrounds, triple heterozygous Mib1 Apcdd1 Asxl3 mice showed LVNC, whereas quadruple heterozygous Mib1 Cep192 Tmx3;Bcl7a mice developed bicuspid aortic valve and other valve-associated defects. Biochemical analysis suggested interactions between CEP192, BCL7A, and NOTCH. Gene expression profiling of mutant mouse hearts and human induced pluripotent stem cell-derived cardiomyocytes revealed increased cardiomyocyte proliferation and defective morphological and metabolic maturation. These findings reveal a shared genetic substrate underlying LVNC and bicuspid aortic valve in which MIB1-NOTCH variants plays a crucial role in heterozygous combination with cosegregating genetic modifiers.This study was supported by grants PID2019-104776RB-I00 and PID2020-120326RB-I00, CB16/11/00399 (CIBER CV) financed by MCIN/AEI/10.13039/501100011033, a grant from the Fundación BBVA (Ref. BIO14_298), and a grant from Fundació La Marató de TV3 (Ref. 20153431) to J.L.d.l.P. M.S.-A. was supported by a PhD contract from the Severo Ochoa Predoctor-al Program (SVP-2014-068723) of the MCIN/AEI/10.13039/501100011033. J.R.G.-B. was supported by SEC/FEC-INV-BAS 21/021. A.R. was funded by grants from MCIN (PID2021123925OB-I00), TerCel (RD16/0011/0024), AGAUR (2017-SGR-899), and Fundació La Marató de TV3 (201534-30). J.M.P.-P. was supported by RTI2018-095410-B-I00 (MCIN) and PY2000443 (Junta de Andalucía). B.I. was supported by the European Commission (H2020-HEALTH grant No. 945118) and by MCIN (PID2019-107332RB-I00). DO’R was sup-ported by the Medical Research Council (MC-A658-5QEB0) and KAMcG by the British Heart Foundation (RG/19/6/34387, RE/18/4/34215). The cost of this publication was supported in part with funds from the European Regional Devel-opment Fund. The Centro Nacional de Investigaciones Cardiovasculares is sup-ported by the ISCIII, the MCIN, and the Pro Centro Nacional de Investigaciones Cardiovasculares Foundation and is a Severo Ochoa Center of Excellence (grant CEX2020001041-S) financed by MCIN/AEI/10.13039/501100011033. For the purpose of open access, the authors have applied a CC BY public copyright license to any Author Accepted Manuscript version arising.S

    Hypoxia Inducible Factor 1-Alpha (HIF-1 Alpha) Is Induced during Reperfusion after Renal Ischemia and Is Critical for Proximal Tubule Cell Survival

    Get PDF
    Acute tubular necrosis (ATN) caused by ischemia/reperfusion (I/R) during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α), using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant

    Impact of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients: A nationwide study in Spain

    Get PDF
    Objective To assess the effect of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients in Spain. Settings The initial flood of COVID-19 patients overwhelmed an unprepared healthcare system. Different measures were taken to deal with this overburden. The effect of these measures on neurosurgical patients, as well as the effect of COVID-19 itself, has not been thoroughly studied. Participants This was a multicentre, nationwide, observational retrospective study of patients who underwent any neurosurgical operation from March to July 2020. Interventions An exploratory factorial analysis was performed to select the most relevant variables of the sample. Primary and secondary outcome measures Univariate and multivariate analyses were performed to identify independent predictors of mortality and postoperative SARS-CoV-2 infection. Results Sixteen hospitals registered 1677 operated patients. The overall mortality was 6.4%, and 2.9% (44 patients) suffered a perioperative SARS-CoV-2 infection. Of those infections, 24 were diagnosed postoperatively. Age (OR 1.05), perioperative SARS-CoV-2 infection (OR 4.7), community COVID-19 incidence (cases/10 5 people/week) (OR 1.006), postoperative neurological worsening (OR 5.9), postoperative need for airway support (OR 5.38), ASA grade =3 (OR 2.5) and preoperative GCS 3-8 (OR 2.82) were independently associated with mortality. For SARS-CoV-2 postoperative infection, screening swab test <72 hours preoperatively (OR 0.76), community COVID-19 incidence (cases/10 5 people/week) (OR 1.011), preoperative cognitive impairment (OR 2.784), postoperative sepsis (OR 3.807) and an absence of postoperative complications (OR 0.188) were independently associated. Conclusions Perioperative SARS-CoV-2 infection in neurosurgical patients was associated with an increase in mortality by almost fivefold. Community COVID-19 incidence (cases/10 5 people/week) was a statistically independent predictor of mortality. Trial registration number CEIM 20/217

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

    Get PDF
    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    PATJ Low Frequency Variants Are Associated with Worse Ischemic Stroke Functional Outcome: A Genome-Wide Meta-Analysis

    Get PDF
    RATIONALE: Ischemic stroke is among the leading causes of adult disability. Part of the variability in functional outcome after stroke has been attributed to genetic factors but no locus has been consistently associated with stroke outcome. OBJECTIVE: Our aim was to identify genetic loci influencing the recovery process using accurate phenotyping to produce the largest GWAS (genome-wide association study) in ischemic stroke recovery to date. METHODS AND RESULTS: A 12-cohort, 2-phase (discovery-replication and joint) meta-analysis of GWAS included anterior-territory and previously independent ischemic stroke cases. Functional outcome was recorded using 3-month modified Rankin Scale. Analyses were adjusted for confounders such as discharge National Institutes of Health Stroke Scale. A gene-based burden test was performed. The discovery phase (n=1225) was followed by open (n=2482) and stringent joint-analyses (n=1791). Those cohorts with modified Rankin Scale recorded at time points other than 3-month or incomplete data on previous functional status were excluded in the stringent analyses. Novel variants in PATJ (Pals1-associated tight junction) gene were associated with worse functional outcome at 3-month after stroke. The top variant was rs76221407 (G allele, β=0.40, P=1.70×10-9). CONCLUSIONS: Our results identify a set of common variants in PATJ gene associated with 3-month functional outcome at genome-wide significance level. Future studies should examine the role of PATJ in stroke recovery and consider stringent phenotyping to enrich the information captured to unveil additional stroke outcome loci
    corecore