256 research outputs found

    A yeast three-hybrid system that reconstitutes mammalian hypoxia inducible factor regulatory machinery

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    Background: Several human pathologies, including neoplasia and ischemic cardiovascular diseases, course with an unbalance between oxygen supply and demand ( hypoxia). Cells within hypoxic regions respond with the induction of a specific genetic program, under the control of the Hypoxia Inducible Factor (HIF), that mediates their adaptation to the lack of oxygen. The activity of HIF is mainly regulated by the EGL-nine homolog (EGLN) enzymes that hydroxylate the alpha subunit of this transcription factor in an oxygen-dependent reaction. Hydroxylated HIF is then recognized and ubiquitinilated by the product of the tumor suppressor gene, pVHL, leading to its proteosomal degradation. Under hypoxia, the hydroxylation of HIF by the EGLNs is compromised due to the lack of oxygen, which is a reaction cosubstrate. Thus, HIF escapes degradation and drives the transcription of its target genes. Since the progression of the aforementioned pathologies might be influenced by activation of HIF-target genes, development of small molecules with the ability to interfere with the HIF-regulatory machinery is of great interest.Results: Herein we describe a yeast three-hybrid system that reconstitutes mammalian HIF regulation by the EGLNs and VHL. In this system, yeast growth, under specific nutrient restrictions, is driven by the interaction between the beta domain of VHL and a hydroxyproline-containing HIF alpha peptide. In turn, this interaction is strictly dependent on EGLN activity that hydroxylates the HIFa peptide. Importantly, this system accurately preserves the specificity of the hydroxylation reaction toward specific substrates. We propose that this system, in combination with a matched control, can be used as a simple and inexpensive assay to identify molecules that specifically modulate EGLN activity. As a proof of principle we show that two known EGLN inhibitors, dimethyloxaloylglycine (DMOG) and 6-chlor-3-hydroxychinolin-2-carbonic acid-N-carboxymethylamide (S956711), have a profound and specific effect on the yeast HIF/EGLN/VHL system.Conclusion: The system described in this work accurately reconstitutes HIF regulation while preserving EGLN substrate specificity. Thus, it is a valuable tool to study HIF regulation, and particularly EGLN biochemistry, in a cellular context. In addition, we demonstrate that this system can be used to identify specific inhibitors of the EGLN enzymes

    Positive parenting style and positive health beyond the authoritative: Self, universalism values, and protection against emotional vulnerability from Spanish adolescents and adult children

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    IntroductionRecent research is fully questioning whether the combination of parenting warmth and strictness (the authoritative style) is always identified as positive parenting across the globe. This study analyzes parenting styles and the positive health of adolescents and adult children.MethodsThe sample was 2,090 Spanish children (59.9% women), from four age groups: 600 adolescents, 591 young adults, 507 middle-aged adults, and 392 older adults. Parenting styles (indulgent, authoritative, authoritarian, and neglectful) were obtained by warmth and strictness measures. Children’s positive health was measured by self (family self-concept, self-esteem, and negative self-efficacy), universalism values, and emotional vulnerability.ResultsThe main results showed that the indulgent parenting style was associated with equal and even better scores than the authoritative style, whereas the authoritarian and neglectful styles were consistently associated with low scores in positive health indicators for all age groups. However, two triple interactions of sex by age group by parenting style showed that women children from neglectful families reported the lowest family self-concept in old age and the highest emotional vulnerability in middle age.DiscussionThe study findings question the universal benefits of the so-called positive parenting (the authoritative style) for positive health

    ¿Cuál es el estilo parental óptimo para adolescentes con baja vs. alta autoeficacia? Autoconcepto, desajuste psicológico y rendimiento académico de los adolescentes en el contexto español

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    The aim of this paper is to establish which parenting style is associated with optimum outcomes among adolescents of Spanish families considering adolescents with low vs. high self-efficacy. Although classical studies identify the authoritative parenting style (based on warmth and strictness) as the best parental strategy, emerging research seriously questions the benefits of parental strictness. Additionally, the impact of parenting on the adolescent’s psychosocial competence has been studied for years, but less is known about whether it might vary depending on individual characteristics of the adolescent (e.g., self-efficacy). Participants were 1029 Spanish adolescents, 453 males (44%), aged 12-17 years. Families were classified in one of the parenting styles groups (authoritative, authoritarian, indulgent, or neglectful), and adolescents were grouped by low vs. high self-efficacy. Adolescent psychosocial competence was examined through emotional and academic self-concept, psychological maladjustment (hostility/aggression, negative self-esteem, emotional responsivity, instability, and negative view of the world), and academic performance (grade point average and number of failing grades). Main and interaction effects of parenting style and adolescent self-efficacy were tested. Main effect results indicated that adolescents with low self-efficacy were always associated with the worst psychosocial competence. Consistently, the main effect findings indicated that adolescents from indulgent and authoritative families were associated with better results than those from neglectful and authoritarian families. However, the indulgent parenting style yielded the best results. The impact of parenting might not be the same for adolescents in all cultural contexts. Contrary to findings from classical studies, parental strictness seems to be unnecessary or even detrimental for adolescents with low and high self-efficacy.El objetivo de este estudio es identificar qué estilo parental se asocia con resultados óptimos entre los adolescentes de familias españolas considerando aquellos con baja vs. alta autoeficacia. Los participantes fueron 1029 adolescentes españoles, 453 varones (44%), de 12 a 17 años. Aunque los estudios clásicos identifican el estilo autorizativo (basado en el afecto y la severidad) como la mejor estrategia socializadora, las investigaciones emergentes cuestionan seriamente los beneficios de la severidad parental. Además, el impacto de la socialización parental en la competencia psicosocial del adolescente se ha estudiado durante años, pero se sabe menos sobre si podría variar en función de las características individuales del adolescente (e.g., la autoeficacia). Las familias fueron clasificadas por estilo parental (autorizativo, autoritario, indulgente o negligente), y los adolescentes por baja vs. alta autoeficacia. La competencia psicosocial se examinó a través del autoconcepto emocional y académico, el desajuste psicológico (hostilidad/agresión, autoestima negativa, irresponsividad emocional, inestabilidad emocional y visión negativa del mundo) y el rendimiento académico (nota media y número de cursos repetidos). Se comprobaron los efectos principales y de interacción de estilo parental y autoeficacia. Los resultados de los efectos principales indicaron que los adolescentes con baja autoeficacia presentaban siempre la peor competencia psicosocial. También que los adolescentes de familias indulgentes y autorizativas presentaron mejores resultados que los de familias negligentes y autoritarias. Sin embargo, el estilo parental indulgente se asoció a los mejores resultados. El impacto de la socialización parental podría no ser igual en todos los contextos culturales. Frente a los resultados de los estudios clásicos, la severidad parental parece ser innecesaria o incluso perjudicial para los adolescentes con baja y alta autoeficacia

    Analyzing when parental warmth but without parental strictness leads to more adolescent empathy and self-concept: Evidence from Spanish homes

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    IntroductionClassical research mainly conducted with European-American families has identified the combination of warmth and strictness (authoritative style) as the parenting always associated with the highest scores on developmental outcomes. Additionally, despite the benefits of empathy for prosocial behaviors and protection against antisocial behaviors, most research has considered the contribution of specific practices (e.g., reasoning or power assertion), but not so much the parenting styles. Similarly, family studies tend to study the relationship between parenting and global self-perceptions (self-esteem), but not so much those of each dimension (self-concept).MethodsIn the present study, 600 Spanish adolescents from 12 to 17 years old (M = 15.25, SD = 2.01) were classified within one of the four household typologies (i.e., authoritative, indulgent, authoritarian, or neglectful). Adolescent developmental outcomes were cognitive empathy (adopting perspectives and emotional understanding), emotional empathy (empathic stress and empathic happiness), and self-concept (academic, social, emotional, family and physical).ResultsThe results showed that the indulgent parenting (warmth but not strictness) was related to equal or even better empathy and self-concept than the authoritative style (warmth and strictness), whereas non-warm parenting (authoritarian and neglectful) was consistently associated with poor results.DiscussionOverall, the present findings seriously question that parental strictness combined with parental warmth (authoritative style) is always the parenting style related to the greatest outcomes. By contrast, it seems that reasoning, warmth and involvement, without strictness (indulgent parenting) help adolescents to achieve a good orientation toward others in terms of cognitive and affective empathy and a good self-evaluation in terms of self-concept

    A yeast three-hybrid system that reconstitutes mammalian hypoxia inducible factor regulatory machinery

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    <p>Abstract</p> <p>Background</p> <p>Several human pathologies, including neoplasia and ischemic cardiovascular diseases, course with an unbalance between oxygen supply and demand (hypoxia). Cells within hypoxic regions respond with the induction of a specific genetic program, under the control of the Hypoxia Inducible Factor (HIF), that mediates their adaptation to the lack of oxygen. The activity of HIF is mainly regulated by the EGL-nine homolog (EGLN) enzymes that hydroxylate the alpha subunit of this transcription factor in an oxygen-dependent reaction. Hydroxylated HIF is then recognized and ubiquitinilated by the product of the tumor suppressor gene, pVHL, leading to its proteosomal degradation. Under hypoxia, the hydroxylation of HIF by the EGLNs is compromised due to the lack of oxygen, which is a reaction cosubstrate. Thus, HIF escapes degradation and drives the transcription of its target genes. Since the progression of the aforementioned pathologies might be influenced by activation of HIF-target genes, development of small molecules with the ability to interfere with the HIF-regulatory machinery is of great interest.</p> <p>Results</p> <p>Herein we describe a yeast three-hybrid system that reconstitutes mammalian HIF regulation by the EGLNs and VHL. In this system, yeast growth, under specific nutrient restrictions, is driven by the interaction between the β domain of VHL and a hydroxyproline-containing HIFα peptide. In turn, this interaction is strictly dependent on EGLN activity that hydroxylates the HIFα peptide. Importantly, this system accurately preserves the specificity of the hydroxylation reaction toward specific substrates. We propose that this system, in combination with a matched control, can be used as a simple and inexpensive assay to identify molecules that specifically modulate EGLN activity. As a proof of principle we show that two known EGLN inhibitors, dimethyloxaloylglycine (DMOG) and 6-chlor-3-hydroxychinolin-2-carbonic acid-N-carboxymethylamide (S956711), have a profound and specific effect on the yeast HIF/EGLN/VHL system.</p> <p>Conclusion</p> <p>The system described in this work accurately reconstitutes HIF regulation while preserving EGLN substrate specificity. Thus, it is a valuable tool to study HIF regulation, and particularly EGLN biochemistry, in a cellular context. In addition, we demonstrate that this system can be used to identify specific inhibitors of the EGLN enzymes.</p

    On the viability of chitosan-derived mesoporous carbons as supports for PtCu electrocatalysts in PEMFC

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    Chitosan is an abundant and non-toxic natural polysaccharide rich in nitrogen, which is used here to obtain N-doped mesoporous carbons (NMCs) as supports for Pt-saving PtCu alloy elecrocatalysts, which can be of interest for low-temperature fuels cells. NMCs with different textural properties were synthesized from cheap silica templates. They presented relative dominance of disordered graphitic lattice and comparable amounts of pyrrolic and pyridinic N, with different specific BET surface areas (715-1040 m2 g−1) and mesopore (1.2-2.4 cm3 g−1) and micropore volumes (0.1-0.6 cm3 g−1). PtCu nanoparticles were deposited by Cu electroless deposition and further galvanic exchange with Pt, with overall Pt loadings about 20 wt.%. Pt-rich PtCu alloy crystallites with contracted Pt fcc lattices and sizes of 3.1-4.7 nm were formed. The synthesized PtCu/NMCs catalysts presented better specific current densities for the oxygen reduction and better CO tolerance and specific current densities for the methanol oxidation reaction than those of commercial Pt/C and PtCu/CMK-3. The PtCu/NMC prepared with the H2SO4-activated NMC was the most active catalyst. The different textural properties of the carbonaceous materials appeared to determine the surface structure of the PtCu nanoparticles

    Tomografía por emisión de positrones (PET) en oncología clínica no neurológica

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    Objetivos: Se recogen los resultados de una revisión de la literatura científica sobre la eficacia diagnóstica de la PET en algunas condiciones oncológicas, exceptuando los tumores cerebrales. Se han analizado los parámetros diagnósticos de sensibilidad (Se), especificidad (Sp) y exactitud diagnóstica, en comparación (cuando ha sido posible) con otras tecnologías de imagen alternativas.Introducción, Objetivo y Ámbito del Informe, Métodos y resultados generales de la revisión sistemática de la evidencia científica, Resultados clínicos de la revisión sistemática de la evidencia científica, Resultados de la revisión no sistemática en otros cánceres, Discusión, Conclusiones. Anexo I: Cobertura en EE.UU. y Canadá, Anexo II: Fichas bibliográficas del estudio 1996, analizadas por la AETS. Referencias

    Eficacia de la vacuna meningocócica de polisacárido capsular del grupo C

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    Este informe consiste esencialmente en una revisión sistemática de la literatura científica sobre los efectos, intensidad y duración de la respuesta serológica, así como sobre la eficacia, efectividad y seguridad de la vacuna meningocócica de polisacárido capsular del grupo C.Resumen, Abstract, Abstract INAHTA, Presentación, Introducción Etiología, distribución, diagnóstico, Situación actual de la enfermedad meningocócica en España, Portadores, mecanismo de transmisión e inmunidad, Vacuna meningocócica de polisacáridos capsulares purificados de los grupos A y C, Eficacia y seguridad de la vacuna meningocócica de polisacáridos capsulares purificados de los grupos A y C, Método Eficacia, Inicio de efecto protector, Duración, Reacciones adversas Interacciones, Revacunación, Indicaciones de la vacuna, Recomendaciones sobre el uso de la vacuna meningocócica de polisacárido capsular del grupo C de instituciones y asociaciones profesionales, Resumen Bibliografía

    LHC signals of radiatively-induced neutrino masses and implications for the Zee-Babu model

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    Contrary to the see-saw models, extended Higgs sectors leading to radiatively-induced neutrino masses do require the extra particles to be at the TeV scale. However, these new states have often exotic decays, to which experimental LHC searches performed so far, focused on scalars decaying into pairs of same-sign leptons, are not sensitive. In this paper we show that their experimental signatures can start to be tested with current LHC data if dedicated multi-region analyses correlating different observables are used. We also provide high-accuracy estimations of the complicated Standard Model backgrounds involved. For the case of the Zee-Babu model, we show that regions not yet constrained by neutrino data and low-energy experiments can be already probed, while most of the parameter space could be excluded at the 95% C.L. in a high-luminosity phase of the LHC

    Incidence of co-infections and superinfections in hospitalised patients with COVID-19: a retrospective cohort study

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    Objectives: To describe the burden, epidemiology and outcomes of co-infections and superinfections occurring in hospitalized patients with coronavirus disease 2019 (COVID-19). Methods: We performed an observational cohort study of all consecutive patients admitted for ≥48 hours to the Hospital Clinic of Barcelona for COVID-19 (28 February to 22 April 2020) who were discharged or dead. We describe demographic, epidemiologic, laboratory and microbiologic results, as well as outcome data retrieved from electronic health records. Results: Of a total of 989 consecutive patients with COVID-19, 72 (7.2%) had 88 other microbiologically confirmed infections: 74 were bacterial, seven fungal and seven viral. Community-acquired co-infection at COVID-19 diagnosis was uncommon (31/989, 3.1%) and mainly caused by Streptococcus pneumoniae and Staphylococcus aureus. A total of 51 hospital-acquired bacterial superinfections, mostly caused by Pseudomonas aeruginosa and Escherichia coli, were diagnosed in 43 patients (4.7%), with a mean (SD) time from hospital admission to superinfection diagnosis of 10.6 (6.6) days. Overall mortality was 9.8% (97/989). Patients with community-acquired co-infections and hospital-acquired superinfections had worse outcomes. Conclusions: Co-infection at COVID-19 diagnosis is uncommon. Few patients developed superinfections during hospitalization. These findings are different compared to those of other viral pandemics. As it relates to hospitalized patients with COVID-19, such findings could prove essential in defining the role of empiric antimicrobial therapy or stewardship strategies
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