213 research outputs found

    Nuevos métodos de extracción y fraccionamiento de carbohidratos bioactivos

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    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de lectura: 27-11-2015The extraction of bioactive carbohydrates, such as inositols and prebiotics, from natural sources is of great interest for their use as food ingredients due to the benefits they represent to consumers' health. These compounds are involved in several biological processes related with metabolic disorders or inducing changes in gut microbiota. The potential use of these bioactive ingredients from the food and / or pharmaceutical industry makes that the search for new extraction alternatives, more effective and advantageous than the available ones, gains an increasing importance. Therefore, the main objective of this PhD dissertation is the development of new methods for the extraction and selective fractionation of bioactive carbohydrates (inositol and prebiotics). To achieve this goal, two main research lines have been addressed: (i) the evaluation of the use of new solvents (ionic liquids, ILs) for the selective fractionation of carbohydrates based on their chemical structure, and (ii) the development of new methods of extraction and enrichment of bioactive carbohydrates from natural matrices. First of all, it was necessary to develop a derivatization method that allows the analysis of low molecular weight carbohydrates (LMWC) dissolved in ILs by gas chromatography (GC). The optimized and validated method proved to be effective for this purpose, being this the first time that carbohydrates dissolved in ILs are analyzed by this technique. Subsequently, and due to the scarce data published so far in the literature on the solubility of LMWC in ILs, solubility studies of different monosaccharides, polyols, disaccharides and trisaccharides in methyl-imidazolium based-ILs were carried out, and these values were related to their chemical structure. ILs were found to be promising solvents for the selective fractionation of aldoses and bioactive ketoses, such as lactose and lactulose, as well as several polyols and other LMWC. Prior to the development of extraction methods, significant advances in qualitative and quantitative determination of the LMWC (particularly inositol and prebiotics) present in different food matrices (pine nuts, vegetables, legumes) were carried out by GC-MS after derivatization to their corresponding trimethylsylil oximes (TMSO). Different carbohydrates were identified for the first time in these matrices. In this thesis, pressurized liquid extraction (PLE) and microwave assisted extraction (MAE) were selected to evaluate their efficiency in the extraction of bioactive carbohydrates, as well as their respective advantages and disadvantages. The developed PLE and MAE methods allowed to obtain greater yields of inositols than those achieved by the conventional solid-liquid extraction method, using shorter extraction times and with a lower solvent consumption. Moreover, the developed methods allowed, for the first time, the simultaneous extraction of inositol and inulin from food industry by-products. Finally, a biotechnological process based on the use of Saccharomyces cerevisiae which allowed the removal of coexisting sugars in the extracts that might interfere with the bioactivity of the carbohydrates of interest has been optimized. The results described in this thesis represent a remarkable contribution to the study of carbohydrates, as well as to the development of new ingredients and bioactive supplements, which is a subject of great interest and scientific and economic impac

    La comunicación como factor clave en la implantación de la responsabilidad social corporativa: el caso de Crédit Agricole España

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    This paper considers the role of communication in the implementation of corporate social responsibility (CSR) as a vital management system for achieving advantages and motivation in employees. The paper also highlights the relevant functions assumed by information professionals to overcome communication deficiencies and lack of knowledge about these relatively new areas of responsibility. A case study of Crédit Agricole España (CAE) is presented, with results that highlight the importance of all the communication-related aspects of implementing CSR

    Use of room temperature ionic liquids for the selective fractionation of bioactive ketoses from aldoses

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    This work deals with the effective fractionation of bioactive ketoses, i.e. lactulose and tagatose, from their corresponding aldoses, lactose and galactose, in equimolar binary mixtures driven by room temperature ionic liquids, i.e. 1-ethyl-3-methylimidazolium dicyanamide ([EMIM][DCA]) and 1-butyl-3-methylimidazolium methyl sulfate ([BMIM][MeSO4]), respectively. Under assayed conditions, tagatose was found to be 6-fold more soluble on [BMIM][MeSO4] than galactose; meanwhile lactulose was 3 times more soluble than lactose on [EMIM][DCA]. As an application example in a more complex sample, a lactose isomerization mixture containing in addition lactulose and monosaccharides was enriched in this ketose by using [EMIM][DCA]. Carbohydrates were then successfully recovered from the ionic liquid following an activated charcoal-based treatment. Overall, lactulose content was enriched from a 24% in the initial isomerization reaction mixture to a 62% in the purified sample. These experimental results demonstrated the potential of ionic liquids as green alternative solvents for the selective fractionation of bioactive ketoses from their corresponding aldoses in food and beverage production.Authors thank Ministerio de Ciencia e InnovaciĂłn (projects AGL2009-11909 and AGL2011-27884), Ministerio de EconomĂ­a y Competitividad (project CTQ2012-32957) and the European founding from FEDER program for financial support. L. Ruiz-Aceituno is supported by CSIC by a JAE-Pre grant, co-financed by the European Social Fund (ESF). C. Carrero-Carralero thanks Ministerio de Ciencia e InnovaciĂłn (Spain) for a predoctoral contract.Peer Reviewe

    T35: a small automatic telescope for long-term observing campaigns

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    The T35 is a small telescope (14") equipped with a large format CCD camera installed in the Sierra Nevada Observatory (SNO) in Southern Spain. This telescope will be a useful tool for the detecting and studying pulsating stars, particularly, in open clusters. In this paper, we describe the automation process of the T35 and show also some images taken with the new instrumentation.Comment: 13 pages, 9 figures. Accepted for publication in the special issue "Robotic Astronomy" of Advances of Astronom

    Characterisation of night-time outdoor lighting in urban centres using cluster analysis of remotely sensed light emissions

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    Evidence of the negative impact of light pollution on ecosystems is increasing every year. Its monitoring and study requires the identification, characterisation and control of the emitting sources. This is the case of urban centres with outdoor lighting that spills light outside the place it is intended to illuminate. The quantity and nature of the pollutant (artificial light at night) depends on the lamps used and how they are positioned. This is important because a greater proportion of blue light means a greater scattering effect. In this study, we analysed the emissions of 100 urban centres in the north of Granada province (Spain), using International Space Station (ISS) images from 2012 and 2021, in order to compare the results with public lighting inventories and verify the validity of these data for characterising night-time lighting emissions. Using inference and cluster analysis techniques, we confirmed an overall increase in emissions and a shift in their colour towards blue, consistent with the results of the lighting inventory analysis. We concluded that it is possible to use ISS imagery to characterise artificial light emissions and the lighting that causes them, none the less there are a number of inherent problems with the data and the way it was collected that require the results to be interpreted with caution

    The TELE-DD project on treatment nonadherence in the population with type 2 diabetes and comorbid depression

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    Diabetic patients have increased depression rates, diminished quality of life, and higher death rates due to depression comorbidity or diabetes complications. Treatment adherence (TA) and the maintenance of an adequate and competent self-care are crucial factors to reach optimal glycaemic control and stable quality of life in these patients. In this report, we present the baseline population analyses in phase I of the TELE-DD project, a three-phased population-based study in 23 Health Centres from the Aragonian Health Service Sector II in Zaragoza, Spain. The objectives of the present report are: (1) to determine the point prevalence of T2D and clinical depression comorbidity and treatment nonadherence; (2) to test if HbA1c and LDL-C, as primary DM outcomes, are related to TA in this population; and (3) to test if these DM primary outcomes are associated with TA independently of shared risk factors for DM and depression, and patients’ health behaviours. A population of 7,271 patients with type-2 diabetes and comorbid clinical depression was investigated for inclusion. Individuals with confirmed diagnoses and drug treatment for both illnesses (n = 3340) were included in the current phase I. A point prevalence of 1.9% was found for the T2D-depression comorbidity. The prevalence of patients nonadherent to treatment for these diseases was 35.4%. Multivariate analyses confirmed that lower diabetes duration, increased yearly PCS visits, HbA1c and LDL-C levels were independently related to treatment nonadherence. These findings informed the development of a telephonic monitoring platform for treatment of nonadherence for people with diabetes and comorbid depression and further trial, cost-effectiveness, and prognostic studies (phases II and III)

    The Low Incidence of Viral Hepatitis Reactivation Among Subjects on Immunotherapy Reduces the Impact of Suboptimal Screening Rate

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    Cancer; Checkpoint inhibitors; Hepatitis BCáncer; Inhibidores del punto de control; Hepatitis BCàncer; Inhibidors del punt de control; Hepatitis BBackground and Aims: Immunotherapy with immune checkpoint inhibitors (ICIs) is a pillar of many advanced tumors. However, there is scarce data concerning the rate of viral hepatitis screening in this population or the risk of viral reactivation. Methods: Retrospective–prospective study that includes all patients who began ICIs between January/2019 and December/2020 in a University Hospital. Data on viral hepatitis screening prior to the beginning of ICIs were collected. In subjects lacking information, serological tests were requested prospectively. Among HBsAg, anti-HBc, or anti-HCV positive subjects, reactivation was prospectively assessed. Results: During the 2-year period of study, 595 subjects received ICIs (61.2% male, mean age 63 years). The most prevalent cancers found were 35.5% lung cancer, 12.1% melanoma, and 8.2% head and neck; ICIs schemes were mainly anti-PD1 (65.7%), followed by anti-PD-L1 (19.2%), and combined therapy (13.6%). Prior to immunotherapy, anti-HCV screening was performed in 462 (77.6%) subjects, HBsAg in 462 (77.6%), anti-HBc in 335 (56.3%), and the complete screening in 328 (55.1%). The anti-HBc screening was more frequently ordered among patients treated with concomitant systemic therapy (p = 0.003), especially in the case of chemotherapy (p = 0.015), though HCV screening was more commonly performed in concomitant therapies different from chemotherapy (p = 0.001). Serological tests were completed prospectively in those alive, leading to an overall prevalence for anti-HCV of 3.5%, HBsAg at 1.3%, and anti-HBc of 15.2%. HCV-RNA was detected in 2/19 (both patients with hepatocellular carcinoma), HBV-DNA in 4/7 HBsAg positive, and in 1/75 anti-HBc positive subject. Five out of the 7 HBsAg carriers and 1/75 anti-HBc+ subjects (due to concomitant antiretroviral therapy) received antiviral prophylaxis. Neither cases of HBV reactivation nor changes in HCV viral load were observed. Discussion: HBV and HCV screening prior to immunotherapy is suboptimal. Though the rate of viral hepatitis reactivation seems extremely low, efforts should be made to optimize viral hepatitis screening prior to immunotherapy for the selection of candidates for either antiviral prophylaxis or periodical follow-up
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