147 research outputs found

    Diseño de una columna de absorción de gases en la Planta de Producción del Centro de Bioactivos Químicos

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    El proceso de producción del 2-(2-nitrovinil-furano) como producto intermedio para la elaboración de lingrediente farmacéutico 2-bromo-5-(2-bromo-2-nitrovinil-furano) se lleva a cabo a través de síntesis química a partir de la condensación del Furfural, etapa mediante la cual se liberan gases nitrosos causantes de la contaminación en el taller. En el presente trabajo se propuso un nuevo proceso de lavado de gases nitrosos mediante la incorporación de una columna absorbedora rellena que sustituye a las trampas de absorción que se utilizaban anteriormente en el proceso. Con las mediciones de gases realizadas en el ambiente de trabajo se demostró que para una hora de exposición la concentración de gases supera a 0,16 mg/m3 según se establece en la normativa ambiental vigente. Se determinaronl os parámetros fundamentales que definieron el diseño de la columna absorbedora y el equipo quedó instalado en el taller de producción con una altura de empaque de 20 cm y diámetro interior de 2,4cm

    COVID-19 and inflammatory bowel disease: questions arising from patient care and follow-up during the initial phase of the pandemic (February-April 2020)

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    COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was described in China in late 2019. There are currently more than three million diagnosed cases, constituting a pandemic which has caused a worldwide crisis. The devastating effects of this infection are due to its highly contagious nature and although mild forms predominate, in absolute values, the rates for severe forms and mortality are very high. The information on the characteristics of the infection in inflammatory bowel disease is of special interest, as these patients have higher attendance at health centres, which may increase their risk of infection. Furthermore, the treatments used to control the inflammatory activity may modify the disease course of COVID-19. The Spanish Working Group on Crohn's Disease and Ulcerative Colitis and the Spanish Nurses Working Group on Inflammatory Bowel Disease have prepared this document as a practical response to some common questions about the treatment of these patients

    Recopilación de métodos analíticos para la caracterización y determinación del quitosano y las principales aplicaciones del polímero en los envases activos alimentarios

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    Antimicrobial films for food packaging applications have received increasing attention from the industry in recent years. Due to their exceptional properties, such as non-toxicity, biodegradability, antimicrobial characteristics, and biocompatibility, chitosan has proven useful for the development of active materials. This review aims to provide anoverview of the main techniques used for the characterization of chitin and chitosan, including Fourier transforminfrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, UV spectrophotometry, viscosimetry, elemental analysis, X-ray diffraction (XRD), thermogravimetric analysis (TGA), titrations, scanning electron microscopy (SEM) and size exclusion chromatography (SEC) among others. In addition, the main applications of the polymer in food packaging are also reportedEn los últimos años los films antimicrobianos han recibido una gran atención por parte de la industria para su aplicación en el envasado alimentario. Debido a sus excepcionales propiedades, no-tóxico, biodegradable, características antimicrobianas y biocompatible, el quitosano ha demostrado ser útil para el desarrollo de materiales activos. Este artículo de revisión tiene por objeto proporcionar una visión general de las principales técnicas usadas para la caracterización de quitina y quitosano incluidas la espectroscopia infrarroja (FTIR), la espectroscopia RMN de 1H y 13C, la espectrofotometría UV, viscosimetría, análisis elemental, difracción de rayos-X (XRD), análisis termogravimétrico (TGA), titulaciones, microscopía electrónica de barrido (SEM) y cromatografía de exclusión por tamaños (SEC)entre otras. Además, se describen las principales aplicaciones del polímero en el envasado de los alimentosThis work was funded under the Project no. 95935 from FONCICYT C002-2008-1/ALA 127 249S

    Detection of Minority Variants and Mixed Infections in Mycobacterium tuberculosis by Direct Whole-Genome Sequencing on Noncultured Specimens Using a Specific-DNA Capture Strategy

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    Detection of mixed Mycobacterium tuberculosis (MTB) infections is essential, particularly when resistance mutations are present in minority bacterial populations that may affect patients' disease evolution and treatment. Whole-genome sequencing (WGS) has extended the amount of key information available for the diagnosis of MTB infection, including the identification of mixed infections. Having genomic information at diagnosis for early intervention requires carrying out WGS directly on the clinical samples. However, few studies have been successful with this approach due to the low representation of MTB DNA in sputa. In this study, we evaluated the ability of a strategy based on specific MTB DNA enrichment by using a newly designed capture platform (MycoCap) to detect minority variants and mixed infections by WGS on controlled mixtures of MTB DNAs in a simulated sputum genetic background. A pilot study was carried out with 12 samples containing 98% of a DNA pool from sputa of patients without MTB infection and 2% of MTB DNA mixtures at different proportions. Our strategy allowed us to generate sequences with a quality equivalent to those obtained from culture: 62.5× depth coverage and 95% breadth coverage (for at least 20× reads). Assessment of minority variant detection was carried out by manual analysis and allowed us to identify heterozygous positions up to a 95:5 ratio. The strategy also automatically distinguished mixed infections up to a 90:10 proportion. Our strategy efficiently captures MTB DNA in a nonspecific genetic background, allows detection of minority variants and mixed infections, and is a promising tool for performing WGS directly on clinical samples. IMPORTANCE We present a new strategy to identify mixed infections and minority variants in Mycobacterium tuberculosis by whole-genome sequencing. The objective of the strategy is the direct detection in patient sputum; in this way, minority populations of resistant strains can be identified at the time of diagnosis, facilitating identification of the most appropriate treatment for the patient from the first moment. For this, a platform for capturing M. tuberculosis-specific DNA was designed to enrich the clinical sample and obtain quality sequences

    High within-host diversity found from direct genotyping on post-mortem tuberculosis specimens in a high-burden setting

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    Objectives: To characterize the clonal complexity in Mycobacterium tuberculosis (MTB) infections considering factors that help maximize the detection of coexisting strains/variants. Methods: Genotypic analysis by Mycobacterial Interspersed Repetitive-Unit-Variable-Number Tandem-Repeats (MIRU-VNTR) was performed directly on 70 biopsy specimens from two or more different tissues involving 28 tuberculosis cases diagnosed post-mortem in Mozambique, a country with a high tuberculosis burden. Results: Genotypic data from isolates collected from two or more tissues were obtained for 23 of the 28 cases (82.1%), allowing the analysis of within-patient diversity. MIRU-VNTR analysis revealed clonal diversity in ten cases (35.7%). Five cases showed allelic differences in three or more loci, suggesting mixed infection with two different strains. In half of the cases showing within-host diversity, one of the specimens associated with clonal heterogeneity was brain tissue. Conclusions: Direct MTB genotyping from post-mortem tissue samples revealed a frequent within-host Mycobacterium tuberculosis diversity, including mixed and polyclonal infections. Most of this diversity would have been overlooked if only standard analysis of respiratory specimens had been performed

    Operations of and Future Plans for the Pierre Auger Observatory

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    Technical reports on operations and features of the Pierre Auger Observatory, including ongoing and planned enhancements and the status of the future northern hemisphere portion of the Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009.Comment: Contributions to the 31st ICRC, Lodz, Poland, July 200

    Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV

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    We describe the measurement of the depth of maximum, Xmax, of the longitudinal development of air showers induced by cosmic rays. Almost four thousand events above 10^18 eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106 +35/-21) g/cm^2/decade below 10^(18.24 +/- 0.05) eV and (24 +/- 3) g/cm^2/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm^2. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.Comment: Accepted for publication by PR
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