130 research outputs found

    Clostridium difficile spores and its relevance in the persistence and transmission of the infection

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    Indexación: Web of Science; Scielo.Clostridium difficile es un patógeno anaerobio, formador de esporas y el agente etiológico más importante de las diarreas asociadas a antimicrobianos, tanto nosocomiales como adquiridas en la comunidad. Las infecciones asociadas a C. difficile poseen una elevada tasa de morbilidad en países desarrollados y en vías de desarrollo. Los dos factores de virulencia principales son TcdA y TcdB, toxinas que causan la remodelación del citoesqueleto lo cual desencadena los síntomas clínicos asociados a esta enfermedad infecciosa. A pesar que las esporas de C. difficile son el principal vehículo de infección, persistencia en el hospedero y de transmisión, pocos estudios se han enfocado sobre este clave aspecto. Es altamente probable que la espora juegue roles esenciales en los episodios de recurrencia y de transmisión horizontal de la infección por este microorganismo. Estudios recientes han revelado características únicas de las esporas de C. difficile que las hacen capaces de ser altamente transmisibles y persistir dentro del hospedero. Más aún, algunas de estas propiedades están relacionadas con la resistencia de sus esporas a los desinfectantes más comúnmente usados en los recintos hospitalarios. La presente revisión resume los conocimientos más relevantes en la biología de las esporas de C. difficile, con un énfasis en aquellos aspectos con implicancias clínicas, incluido el control de infecciones en el ambiente hospitalario.C. difficile is an anaerobic spore former pathogen and the most important etiologic agent of nosocomial and community acquired antibiotics associated diarrheas. C. difficile infections (CDI) are responsible for an elevated rate of morbidity in developed and developing countries. Although the major virulence factors responsible for clinical symptoms of CDI are the two toxins TcdA and TcdB, C. difficile spores are the main vehicle of infection, persistence and transmission of CDI. Recent work has unrevealed unique properties of C. difficile spores that make them remarkable morphotypes of persistence and transmission in the host, including their resistance to antibiotics, the host immune response and disinfectants. The present review summarizes relevant aspects of C. difficile spore biology that have major implications from a clinical and medical perspective.http://ref.scielo.org/3xfbk

    Performance of prognostic index in severe Clostridium difficile-associated infection. Retrospective analysis in a university hospital

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    Indexación: ScieloIntroducción: Por consenso, la infección asociada a Clostridium difficile (IACD) grave es aquella que resulta en hospitalización en unidad de cuidados intensivos, colectomía o muerte dentro de 30 días. Múltiples índices pronósticos (IP) intentan predecir estos eventos adversos. Objetivo: evaluar el rendimiento de cuatro IP en la predicción de IACD grave. Metodología: pacientes hospitalizados ≥ 18 años con IACD fueron evaluados retrospectivamente. Se excluyeron pacientes con infección recurrente o cáncer hematológico. Se evaluaron cuatro IP: UPMC versión 1, Calgary versión 1, Hines VA y Calgary versión 2. Resultados: Siete de 81 pacientes (8,1%) presentaron una IACD grave. El valor predictor positivo (VPP) y valor predictor negativo (VPN) de los IP varió entre 20-75% y 91,3-95,7%, respectivamente. Sólo el índice de Hines VA tuvo un índice Kappa satisfactorio (0,74;IC 95% 0,46-1) con un VPP de 75% y un VPN de 95,7%. Sin embargo, por las variables incluidas en este IP, sólo pudo ser calculado en 32,6% de los pacientes. Conclusión: El índice de Hines VA presenta el mejor valor predictor y concordancia para descartar una IACD grave. Como otros IP, tiene la limitación de incluir variables difícilmente evaluables en todos los pacientes y tiende a sobreestimar un curso desfavorable.Introduction: By consensus severe, Clostridium difficile-associated infection (CDAI) is one that results in hospitalization in ICU, colectomy or death within 30 days. Multiple prognostic indices (IP) attempt to predict these adverse events. Objective: To evaluate the performance of 4 PI in predicting severe CDI. Methods: Hospitalized patients ≥ 18 years old with ICD were retrospectively evaluated. Patients with recurrent infection or hematological cancer were excluded. Four PI were evaluated: UPMC version 1, Calgary version 1, Hines VA and Calgary version 2. Results: Seven of 81 patients (8.1%) met the definition of severe CDI. Positive predicted value (PPV) and negative predicted value (NPV) of PI ranged from 20-75% and 91.3-95.7%, respectively. Only Hines VA index had a satisfactory Kappa index (0.74; 95% CI 0.41-1) with a PPV of 75% and NPV of 95,7%. However, because of the variables included, this PI could be calculated only in 32.6% of patients. Conclusion: Hines VA index has the best predicted value and agreement to rule out a severe CDI. Like others PI it has the limitation of including difficult variables to assess in all patients and tends to overestimate an unfavorable course.http://www.scielo.cl/pdf/rci/v31n6/art03.pd

    Effect of oat β-glucan on glycemic index and glycemic load of a nutritional supplement sweetened with sucralose in healthy adults: A randomized clinical trial

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    Indexación: Scopus; RedalycLas propiedades hipoglicemiantes del β-glucano de avena son de interés para la industria alimentaria y el área clínica, por sus potenciales beneficios sobre la salud al disminuir la respuesta glicémica, el nivel sérico de lipoproteínas de baja densidad y el índice glicémico de los alimentos. Existen suplementos nutricionales específicos para diabéticos edulcorados con sucralosa cuyo índice glicémico y carga glicémica aún no han sido establecidos. El efecto del β-glucano de avena sobre el índice glicémico y carga glicémica de un suplemento nutricional edulcorado con sucralosa, fue determinado en 13 adultos sanos (6 hombres y 7 mujeres), quienes consumieron aleatoriamente 4 alimentos en días distintos, de 50 g de carbohidratos cada uno: suplemento nutricional para diabéticos (FN), suplemento nutricional con β-glucano (FN- β), y como productos de referencia: solución glucosada (SG) y pan blanco (PB). Se midió glicemia en ayunas y post- prandial a los tiempos 15, 30, 45, 60, 90 y 120 min. El área bajo la curva de glicemia resultó más baja para ambas fórmulas (FN) 12697±993, (FN-β) 11584 ±1171, que para los productos de referencia:(SG) 13900±1245, y (PB) 13267 ± 1557. Los valores de índice glicémico (FN) 67,02 ± 5,69, así como la carga glicémica resultaron intermedios y más bajos para el suplemento con β-glucano incorporado (FN –β) 59,8 ± 6,2; sin diferencias en la concentración de insulina, sugiriendo que la adición del β-glucano derivado de la avena reduce la velocidad de absorción intestinal de la glucosa, efecto que podría estudiarse en diabéticos.The hypoglycemic properties of oat β-glucan is of interest for the food industry and clinical area, for potencial health benefits by reducing glycemic response, serum low-density lipoprotein cholesterol, and glycemic index of meals. There are specific nutritional supplements for diabetics sweetened with sucralose whose glycemic index and glycemic load has not been established. Effect of oat β-glucan on glycemic index and glycemic load of a nutritional supplement sweetened with sucralose in healthy adults was determined in 13 healthy subjects (6 men and 7 women) old that consumed randomly 4 meals of 50 g of carbohydrates each in different days: a nutritional supplement for diabetics (FN), the nutritional supplement with β-glucan incorporated (FN-β) and two reference food, glucose solution (SG) and white bread (PB). Fasting and postprandial glycemia was measured at times 15, 30, 45, 60, 90 and 120 min. The area under the glycemia curve was lower for both formulas (FN) 12697±993, (FN-β) 11584 ±1171 than for reference products (SG) 13900±1245, y (PB) 13267 ± 1557. The values of glycemic index (GI) (FN) 67, 02 ± 5,69 and glycemic load were intermediate and more lower for the supplement with β-glucan incorporated (FN –β) 59, 8 ± 6,2, with no difference of insulin concentration . Suggesting that the addition of oat-derived β-glucan reduces the rate of intestinal absorption of glucose. This effect should be studied in diabetic.http://www.redalyc.org/articulo.oa?id=5594990800

    Social times, reproduction and social inequality at work : contrasts and comparative perspectives between countries

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    Production of INCASI Project H2020-MSCA-RISE-2015 GA 691004If the focus is placed specifically on the problem of work and family, the daily life of people and their use of time are a main problem. This time is expressed in both freely available time, which is related to activities, and time of the productive and reproductive sphere. This chapter considers work in a broad sense and takes into account the sexual division of labour. Specifically, this chapter will explore transformations in time use and social inequality in unpaid work. For this purpose, a comparative analysis of time-use surveys will be used, analysing the time spent, and the time dedicated to household chores in Chile, Argentina, Uruguay and Spain. From an analytical viewpoint, the analysis will place social reproduction at the centre of the socio-economic system, showing that the economic crisis has affected women and men differently, and that in both Europe and Latin America the family pattern is being replaced by a dominant family model of a male provider and a double presence of women. The large-scale incorporation of women into the labour market has emphasised the role that women assume in the domestic sphere perpetuating gender segregation in employment and in domestic and care work

    Different rates of spontaneous mutation of chloroplastic and nuclear viroids as determined by high-fidelity ultra-deep sequencing

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    [EN] Mutation rates vary by orders of magnitude across biological systems, being higher for simpler genomes. The simplest known genomes correspond to viroids, subviral plant replicons constituted by circular non-coding RNAs of few hundred bases. Previous work has revealed an extremely high mutation rate for chrysanthemum chlorotic mottle viroid, a chloroplastreplicating viroid. However, whether this is a general feature of viroids remains unclear. Here, we have used high-fidelity ultra-deep sequencing to determine the mutation rate in a common host (eggplant) of two viroids, each representative of one family: the chloroplastic eggplant latent viroid (ELVd, Avsunviroidae) and the nuclear potato spindle tuber viroid (PSTVd, Pospiviroidae). This revealed higher mutation frequencies in ELVd than in PSTVd, as well as marked differences in the types of mutations produced. Rates of spontaneous mutation, quantified in vivo using the lethal mutation method, ranged from 1/1000 to 1/800 for ELVd and from 1/7000 to 1/3800 for PSTVd depending on sequencing run. These results suggest that extremely high mutability is a common feature of chloroplastic viroids, whereas the mutation rates of PSTVd and potentially other nuclear viroids appear significantly lower and closer to those of some RNA viruses.This work was supported by the European Research Council (erc.europa.eu; ERC-2011-StG-281191-VIRMUT to RS), the Spanish Ministerio de Economia y Competitividad (www.mineco.gob.es; BFU2013-41329 grant to RS, BFU2014-56812-P grant to RF, and a predoctoral fellowship to ALC), and the Spanish Junta de Comunidades de Castilla-La Mancha (www.castillalamancha.es;postdoctoral fellowship to CB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.López-Carrasco, MA.; Ballesteros Martínez, C.; Sentandreu, V.; Delgado Villar, SG.; Gago Zachert, SP.; Flores Pedauye, R.; Sanjuan Verdeguer, R. (2017). Different rates of spontaneous mutation of chloroplastic and nuclear viroids as determined by high-fidelity ultra-deep sequencing. PLoS Pathogens. 13(9):1-17. https://doi.org/10.1371/journal.ppat.1006547S117139Ganai, R. A., & Johansson, E. (2016). DNA Replication—A Matter of Fidelity. Molecular Cell, 62(5), 745-755. doi:10.1016/j.molcel.2016.05.003Lynch, M. (2010). Evolution of the mutation rate. Trends in Genetics, 26(8), 345-352. doi:10.1016/j.tig.2010.05.003Sanjuán, R., & Domingo-Calap, P. (2016). Mechanisms of viral mutation. Cellular and Molecular Life Sciences, 73(23), 4433-4448. doi:10.1007/s00018-016-2299-6Gago, S., Elena, S. F., Flores, R., & Sanjuan, R. (2009). 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    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    International Consensus Document on Obstructive Sleep Apnea

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    El objetivo principal de este documento internacional de consenso sobre apnea obstructiva del sueno es proporcionar unas directrices que permitan a los profesionales sanitarios tomar las mejores decisiones en la asistencia de los pacientes adultos con esta enfermedad según un resumen crítico de la literatura más actualizada. El grupo de trabajo de expertos se ha constituido principalmente por 17 sociedades científicas y 56 especialistas con amplia representación geográfica (con la participación de 4 sociedades internacionales), además de un metodólogo experto y un documentalista del Centro Cochrane Iberoamer icano. El documento consta de un manuscrito principal, con las novedades más relevantes del DIC, y una serie de manuscritos online que recogen las búsquedas bibliográficas sistemáticas de cada uno de los apartados del DIC. Este documento no cubre la edad pediátrica ni el manejo del paciente en ventilación mecánica crónica no invasiva (que se publicarán en sendos documentos de consenso aparte)

    MEGARA, the new intermediate-resolution optical IFU and MOS for GTC: getting ready for the telescope

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    MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma that is being built by a Consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain), and UPM (Spain). The instrument is currently finishing AIV and will be sent to GTC on November 2016 for its on-sky commissioning on April 2017. The MEGARA IFU fiber bundle (LCB) covers 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec while the MEGARA MOS mode allows observing up to 92 objects in a region of 3.5x3.5 arcmin2 around the IFU. The IFU and MOS modes of MEGARA will provide identical intermediate-to-high spectral resolutions (RFWHM~6,000, 12,000 and 18,700, respectively for the low-, mid- and high-resolution Volume Phase Holographic gratings) in the range 3700-9800ÅÅ. An x-y mechanism placed at the pseudo-slit position allows (1) exchanging between the two observing modes and (2) focusing the spectrograph for each VPH setup. The spectrograph is a collimator-camera system that has a total of 11 VPHs simultaneously available (out of the 18 VPHs designed and being built) that are placed in the pupil by means of a wheel and an insertion mechanism. The custom-made cryostat hosts a 4kx4k 15-μm CCD. The unique characteristics of MEGARA in terms of throughput and versatility and the unsurpassed collecting are of GTC make of this instrument the most efficient tool to date to analyze astrophysical objects at intermediate spectral resolutions. In these proceedings we present a summary of the instrument characteristics and the results from the AIV phase. All subsystems have been successfully integrated and the system-level AIV phase is progressing as expected
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