169 research outputs found

    Youth-culture or student-culture? The internet use intensity divide among university students and the consequences for academic performance

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    The effects of Internet use on the academic performance of university students is usually analyzed from a deterministic perspective that gives this technology an immanently positive or negative role. In this paper we consider the problem from an alternative point of view. We analyze the actual Internet uses the students engage in and the differences in these according to the students’ characteristics. We aim to explain when spending more time on the Internet has a positive and a negative effect on academic performance and explain why usually a high usage time of internet is correlated with a lower academic achievement

    A novel hybrid nanofibrous strategy to target progenitor cells for cost-effective in situ angiogenesis

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    Although the impact of composites based on Ti-doped calcium phosphate glasses is low compared with that of bioglass, they have been already shown to possess great potential for bone tissue engineering. Composites made of polylactic acid (PLA) and a microparticle glass of 5TiO(2)-44.5CaO-44.5P(2)O(5)-6Na(2)O (G5) molar ratio have already demonstrated in situ osteo-and angiogenesis-triggering abilities. As many of the hybrid materials currently developed usually promote osteogenesis but still lack the ability to induce vascularization, a G5/PLA combination is a cost-effective option for obtaining new instructive scaffolds. In this study, nanostructured PLA-ORMOGLASS (organically modified glass) fibers were produced by electro-spinning, in order to fabricate extra-cellular matrix (ECM)-like substrates that simultaneously promote bone formation and vascularization. Physical-chemical and surface characterization and tensile tests demonstrated that the obtained scaffolds exhibited homogeneous morphology, higher hydrophilicity and enhanced mechanical properties than pure PLA. In vitro assays with rat mesenchymal stem cells (rMSCs) and rat endothelial progenitor cells (rEPCs) also showed that rMSCs attached and proliferated on the materials influenced by the calcium content in the environment. In vivo assays showed that hybrid composite PLA-ORMOGLASS fibers were able to promote the formation of blood vessels. Thus, these novel fibers are a valid option for the design of functional materials for tissue engineering applications

    Elucidating dynamic behavior of synthetic supramolecular polymers in water by hydrogen/deuterium exchange mass spectrometry

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    A comprehensive understanding of the structure, self-assembly mechanism, and dynamics of one-dimensional supramolecular polymers in water is essential for their application as biomaterials. Although a plethora of techniques are available to study the first two properties, there is a paucity in possibilities to study dynamic exchange of monomers between supramolecular polymers in solution. We recently introduced hydrogen/deuterium exchange mass spectrometry (HDX-MS) to characterize the dynamic nature of synthetic supramolecular polymers with only a minimal perturbation of the chemical structure. To further expand the application of this powerful technique some essential experimental aspects have been reaffirmed and the technique has been applied to a diverse library of assemblies. HDX-MS is widely applicable if there are exchangeable hydrogen atoms protected from direct contact with the solvent and if the monomer concentration is sufficiently high to ensure the presence of supramolecular polymers during dilution. In addition, we demonstrate that the kinetic behavior as probed by HDX-MS is influenced by the internal order within the supramolecular polymers and by the self-assembly mechanism.MINECO, Spain, Grant/Award Number: IJCI-2015-252389; Marie Curie FP7 SASSYPOL ITN program, Grant/Award Number: 607602; European Research Council, Grant/Award Number: 788618; Dutch Ministry of Education, Culture and Science, Grant/Award Number: 024.001.03

    Changes in bread consumption and 4-year changes in adiposity in Spanish subjects at high cardiovascular risk

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    The effects of bread consumption change over time on anthropometric measures have been scarcely studied. We analysed 2213 participants at high risk for CVD from the PREvención con DIeta MEDiterrånea (PREDIMED) trial to assess the association between changes in the consumption of bread and weight and waist circumference gain over time. Dietary habits were assessed with validated FFQ at baseline and repeatedly every year during 4 years of follow-up. Using multivariate models to adjust for covariates, long-term weight and waist circumference changes according to quartiles of change in energy-adjusted white and whole-grain bread consumption were calculated. The present results showed that over 4 years, participants in the highest quartile of change in white bread intake gained 0·76 kg more than those in the lowest quartile (P for trend = 0·003) and 1·28 cm more than those in the lowest quartile (P for trend 2 kg) and gaining waist circumference (>2 cm) during follow-up was not associated with increase in bread consumption, but participants in the highest quartile of changes in white bread intake had a reduction of 33 % in the odds of losing weight (>2 kg) and a reduction of 36 % in the odds of losing waist circumference (>2 cm). The present results suggest that reducing white bread, but not whole-grain bread consumption, within a Mediterranean-style food pattern setting is associated with lower gains in weight and abdominal fat

    Identification of Brucella by MALDI-TOF Mass Spectrometry. Fast and Reliable Identification from Agar Plates and Blood Cultures

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    BACKGROUND: MALDI-TOF mass spectrometry (MS) is a reliable method for bacteria identification. Some databases used for this purpose lack reference profiles for Brucella species, which is still an important pathogen in wide areas around the world. We report the creation of profiles for MALDI-TOF Biotyper 2.0 database (Bruker Daltonics, Germany) and their usefulness for identifying brucellae from culture plates and blood cultures. METHODOLOGY/PRINCIPAL FINDINGS: We created MALDI Biotyper 2.0 profiles for type strains belonging to B. melitensis biotypes 1, 2 and 3; B. abortus biotypes 1, 2, 5 and 9; B. suis, B. canis, B ceti and B. pinnipedialis. Then, 131 clinical isolates grown on plate cultures were used in triplicate to check identification. Identification at genus level was always correct, although in most cases the three replicates reported different identification at species level. Simulated blood cultures were performed with type strains belonging to the main human pathogenic species (B. melitensis, B. abortus, B. suis and B. canis), and studied by MALDI-TOF MS in triplicate. Identification at genus level was always correct. CONCLUSIONS/SIGNIFICANCE: MALDI-TOF MS is reliable for Brucella identification to the genus level from culture plates and directly from blood culture bottles

    Recommendations for ophthalmologic practice during the easing of COVID-19 control measures

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    In the context of the COVID-19 pandemic, this paper provides recommendations for medical eye care during the easing of control measures after lockdown. The guidelines presented are based on a literature review and consensus among all Spanish Ophthalmology Societies regarding protection measures recommended for the ophthalmologic care of patients with or without confirmed COVID-19 in outpatient, inpatient, emergency and surgery settings. We recommend that all measures be adapted to the circumstances and availability of personal protective equipment at each centre and also highlight the need to periodically update recommendations as we may need to readopt more restrictive measures depending on the local epidemiology of the virus. These guidelines are designed to avoid the transmission of SARS-CoV-2 among both patients and healthcare staff as we gradually return to normal medical practice, to prevent postoperative complications and try to reduce possible deficiencies in the diagnosis, treatment and follow-up of the ophthalmic diseases. With this update (5th) the Spanish Society of Ophthalmology is placed as one of the major ophthalmology societies providing periodic and systematized recommendations for ophthalmic care during the COVID-19 pandemic

    Evolution after Anti-TNF Discontinuation in Patients with Inflammatory Bowel Disease: A Multicenter Long-Term Follow-Up Study

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    OBJECTIVES:The aims of this study were to assess the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) drugs in patients with inflammatory bowel disease (IBD), to identify the factors associated with relapse, and to evaluate the overcome after retreatment with the same anti-TNF in those who relapsed.METHODS:This was a retrospective, observational, multicenter study. IBD patients who had been treated with anti-TNFs and in whom these drugs were discontinued after clinical remission was achieved were included.RESULTS:A total of 1, 055 patients were included. The incidence rate of relapse was 19% and 17% per patient-year in Crohn''s disease and ulcerative colitis patients, respectively. In both Crohn''s disease and ulcerative colitis patients in deep remission, the incidence rate of relapse was 19% per patient-year. The treatment with adalimumab vs. infliximab (hazard ratio (HR)=1.29; 95% confidence interval (CI)=1.01-1.66), elective discontinuation of anti-TNFs (HR=1.90; 95% CI=1.07-3.37) or discontinuation because of adverse events (HR=2.33; 95% CI=1.27-2.02) vs. a top-down strategy, colonic localization (HR=1.51; 95% CI=1.13-2.02) vs. ileal, and stricturing behavior (HR=1.5; 95% CI=1.09-2.05) vs. inflammatory were associated with a higher risk of relapse in Crohn''s disease patients, whereas treatment with immunomodulators after discontinuation (HR=0.67; 95% CI=0.51-0.87) and age (HR=0.98; 95% CI=0.97-0.99) were protective factors. None of the factors were predictive in ulcerative colitis patients. Retreatment of relapse with the same anti-TNF was effective (80% responded) and safe.CONCLUSIONS:The incidence rate of inflammatory bowel disease relapse after anti-TNF discontinuation is relevant. Some predictive factors of relapse after anti-TNF withdrawal have been identified. Retreatment with the same anti-TNF drug was effective and safe
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