108 research outputs found

    Factores demograficos, socioeconomicos e institucionales que influyen en ele rendimiento academico de los estudiantes universitarios

    Get PDF
    I. Capítulo -- Introducción -- Fundamentos, objetivos, alcance, metodología, resultados, resumen -- Fundamentos -- Objetivos -- Objetivo general -- Objetivos específicos -- Alcance -- Metodología -- Resultados -- Resumen -- El marco teórico -- El marco metodológico -- II. Capítulo II -- Marco teórico -- Introducción -- El marco teórico: notas metodológicas -- ¿Marco teórico vs. marco conceptual? -- Deducción e inducción -- Definiciones conceptuales y operacionales -- Funciones del marco teórico en las teorías -- Estructura lógica y general de las teorías -- Los conceptos básicos de la teoría de la deserción -- Esquema de la trayectoria educativa del estudiante universitario -- Una introducción al estado del arte de los estudios sobre la deserción IModelos teóricos propuestos sobre la deserción -- Definiciones conceptuales de la deserción -- Definiciones pragmáticas de la deserción -- Deserción temporal y deserción “espacial” -- La deserción a través de la trayectoria académica -- Modelos generalistas de la deserción estudiantil -- Modelos de salida de Tinto -- Modelo de desgaste de Bean -- Dos conceptos complementarios claves: retención y persistencia -- Modelos teóricos de la deserción basados en categorías clave -- Modelos psicológicos -- La teoría psicológica de la acción razonada -- El modelo psicológico de la acción académica (MSEA) -- El modelo psicosocial de la integración académica y social -- Modelos sociológicos -- Modelos economicistas -- Modelos institucionales (organizacionales) -- Modelos integrativos (o de interacción) -- El e-learning y la deserción -- Capítulo III -- Marco metodológico -- Introducción -- Cuestiones generales: enfoques hacia la persistencia -- Definiciones clave en el contexto de las teorías generalistas -- Las teorías de la persistencia -- Teorías de la salida del estudiante -- Teorías del desgaste del estudiante -- Los ocho factores comunes de la deserción y la persistencia en las investigaciones más actuales -- Tamaño institucional -- Selectividad institucional -- Instituciones delsector público versus instituciones del sector privado -- Características demográficas del estudiante -- Edad -- Género -- Estatus socio económico (ESE) -- Estado “Primera Generación de Estudiantes” -- Compromisos -- Objetivo: compromiso personal -- Objetivo: compromiso institucional -- Preparación académica y factores de éxito -- Capacidad y rendimiento académico preuniversitario -- Preparación académica en el trayecto universitario propiamente dicho -- Grados universitarios - GPA -- Factores psicosociales y habilidad para el estudio -- Motivación para el logro académico -- Objetivos académicos -- Auto eficacia académica -- Auto concepto general -- Habilidades académicas relacionadas -- Integración y ajuste institucional -- Integración académica y ajuste con la comunidad educativa -- Integración social y ajuste del estudiante -- Finanzas estudiantiles -- Ayuda financiera -- Programas de estudio y trabajo (pasantías) -- Matrícula y estudiantes con necesidades no satisfechas -- Factores de atracción ambientales (inductores de salida) -- Empleo -- Obligaciones familiares -- Resumen -- Modelo de trabajo propuesto -- Modelo de funcionamiento del estudiante persistente -- Incluir y mantener a los estudiantes en el ámbito de la educación superior -- Modelo de trabajo: explicaciones adicionales -- Ventajas del nuevo modelo de trabajo -- Capítulo IV --Metodología y análisis de resultados -- Panorama general -- Variables existentes en la base de datos de la UTI -- Variables consideradas en el análisis -- Capítulo V -- Evidencia empírica en la FCE - UNRC -- Aspectos generales de las cohortes 2005, 2006 y 2007 -- Cohorte 2005 -- Cohorte 2006 -- Cohorte 2007 -- Factores que definen el perfil de los estudiantes de Ciencias Económicas -- Factores que explican la situación actual de los estudiantes -- Determinantes de la deserción -- Determinantes del egreso -- Determinantes de la efectividadEste estudio se centra en el análisis de la deserción estudiantil (o, visto desde otra perspectiva, de la persistencia en particular) que se evidencia en el sistema universitario; para tal fin, se indagan tres cohortes de alumnos de la Facultad de Ciencias Económicas de la Universidad Nacional de Río Cuarto correspondientes a los años 2005, 2006 y 2007, inscriptos en las carreras de Contador Público, Licenciado en Administración y Licenciado en Economía. La anormalidad que representa el fenómeno interesa a la comunidad educativa de la institución y, por ende, a sus directivos académicos que, en general, formulan hipótesis para explicar el fenómeno mediante el análisis de los factores socio-económicos y demográficos que incidirían en el rendimiento académico de los alumnos y sus decisiones de abandonar los estudios universitarios, quedando constante el resto de las variables.Fil: Lopez, Ciro R. Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina

    High expression of prolactin receptor is associated with cell survival in cervical cancer cells

    Full text link
    Background: The altered expression of prolactin (PRL) and its receptor (PRLR) has been implicated in breast and other types of cancer. There are few studies that have focused on the analysis of PRL/PRLR in cervical cancer where the development of neoplastic lesions is influenced by the variation of the hormonal status. The aim of this study was to evaluate the expression of PRL/PRLR and the effect of PRL treatment on cell proliferation and apoptosis in cervical cancer cell lines. Results:High expression of multiple PRLR forms and PRLvariants of 60-80 kDa were observed in cervical cancer cell lines compared with non-tumorigenic keratinocytes evaluated by Western blot, immunofluorecence and real time PCR. Treatment with PRL (200 ng/ml) increased cell proliferation in HeLa cells determined by the MTT assay at day 3 and after 1 day a protective effect against etoposide induced apoptosis in HeLa, SiHa and C-33A cervical cancer cell lines analyzed by the TUNEL assay. Conclusions: Our data suggests that PRL/PRLR signaling could act as an important survival factor for cervical cancer. The use of an effective PRL antagonist may provide a better therapeutic intervention in cervical cancer. � 2013 Lopez-Pulido et al.; licensee BioMed Central Ltd

    Sex differences in mortality in patients with COPD

    Get PDF
    Little is known about survival and clinical prognostic factors in females with chronic obstructive pulmonary disease (COPD). The aim of the present study was to determine the survival difference between males and females with COPD and to compare the value of the different prognostic factors for the disease. In total, 265 females and 272 males with COPD matched at baseline by BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity) and American Thoracic Society/European Respiratory Society/Global Initiative of Chronic Obstructive Lung Disease criteria were prospectively followed. Demographics, lung function, St George’s Respiratory Questionnaire, BODE index, the components of the BODE index and comorbidity were determined. Survival was documented and sex differences were determined using Kaplan–Meier analysis. The strength of the association of the studied variables with mortality was determined using multivariate and receiver operating curves analysis. All-cause (40 versus 18%) and respiratory mortality (24 versus 10%) were higher in males than females. Multivariate analysis identified the BODE index in females and the BODE index and Charlson comorbidity score in males as the best predictors of mortality. The area under the curve of the BODE index was a better predictor of mortality than the forced expiratory volume in one second for both sexes. At similar chronic obstructive pulmonary disease severity by BODE index and forced expiratory volume in one second, females have significantly better survival than males. For both sexes the BODE index is a better predictor of survival than the forced expiratory volume in one second

    Mouse Embryonic Retina Delivers Information Controlling Cortical Neurogenesis

    Get PDF
    The relative contribution of extrinsic and intrinsic mechanisms to cortical development is an intensely debated issue and an outstanding question in neurobiology. Currently, the emerging view is that interplay between intrinsic genetic mechanisms and extrinsic information shape different stages of cortical development [1]. Yet, whereas the intrinsic program of early neocortical developmental events has been at least in part decoded [2], the exact nature and impact of extrinsic signaling are still elusive and controversial. We found that in the mouse developing visual system, acute pharmacological inhibition of spontaneous retinal activity (retinal waves-RWs) during embryonic stages increase the rate of corticogenesis (cell cycle withdrawal). Furthermore, early perturbation of retinal spontaneous activity leads to changes of cortical layer structure at a later time point. These data suggest that mouse embryonic retina delivers long-distance information capable of modulating cell genesis in the developing visual cortex and that spontaneous activity is the candidate long-distance acting extrinsic cue mediating this process. In addition, these data may support spontaneous activity to be a general signal coordinating neurogenesis in other developing sensory pathways or areas of the central nervous system

    Chronic obstructive pulmonary disease (COPD) as a disease of early aging: evidence from the epiChron cohort

    Get PDF
    Background: Aging is an important risk factor for most chronic diseases. Patients with COPD develop more comorbidities than non-COPD subjects. We hypothesized that the development of comorbidities characteristically affecting the elderly occur at an earlier age in subjects with the diagnosis of COPD. Methods and findings: We included all subjects carrying the diagnosis of COPD (n = 27,617), and a similar number of age and sex matched individuals without the diagnosis, extracted from the 727,241 records of individuals 40 years and older included in the EpiChron Cohort (Aragon, Spain). We compared the cumulative number of comorbidities, their prevalence and the mortality risk between both groups. Using network analysis, we explored the connectivity between comorbidities and the most influential comorbidities in both groups. We divided the groups into 5 incremental age categories and compared their comorbidity networks. We then selected those comorbidities known to affect primarily the elderly and compared their prevalence across the 5 age groups. In addition, we replicated the analysis in the smokers' subgroup to correct for the confounding effect of cigarette smoking. Subjects with COPD had more comorbidities and died at a younger age compared to controls. Comparison of both cohorts across 5 incremental age groups showed that the number of comorbidities, the prevalence of diseases characteristic of aging and network's density for the COPD group aged 56-65 were similar to those of non-COPD 15 to 20 years older. The findings persisted after adjusting for smoking. Conclusion: Multimorbidity increases with age but in patients carrying the diagnosis of COPD, these comorbidities are seen at an earlier age

    Somatotypes trajectories during adulthood and their association with COPD phenotypes

    Get PDF
    Rationale: Chronic obstructive pulmonary disease (COPD) comprises distinct phenotypes, all characterised by airflow limitation. Objectives: We hypothesised that somatotype changes – as a surrogate of adiposity – from early adulthood follow different trajectories to reach distinct phenotypes. Methods: Using the validated Stunkard’s Pictogram, 356 COPD patients chose the somatotype that best reflects their current body build and those at ages 18, 30, 40 and 50 years. An unbiased group-based trajectory modelling was used to determine somatotype trajectories. We then compared the current COPD-related clinical and phenotypic characteristics of subjects belonging to each trajectory. Measurements and main results: At 18 years of age, 88% of the participants described having a lean or medium somatotype (estimated body mass index (BMI) between 19 and 23 kg·m−2 ) while the other 12% a heavier somatotype (estimated BMI between 25 and 27 kg·m−2 ). From age 18 onwards, five distinct trajectories were observed. Four of them demonstrating a continuous increase in adiposity throughout adulthood with the exception of one, where the initial increase was followed by loss of adiposity after age 40. Patients with this trajectory were primarily females with low BMI and DLCO (diffusing capacity of the lung for carbon monoxide). A persistently lean trajectory was seen in 14% of the cohort. This group had significantly lower forced expiratory volume in 1 s (FEV1), DLCO, more emphysema and a worse BODE (BMI, airflow obstruction, dyspnoea and exercise capacity) score thus resembling the multiple organ loss of tissue (MOLT) phenotype. Conclusions: COPD patients have distinct somatotype trajectories throughout adulthood. Those with the MOLT phenotype maintain a lean trajectory throughout life. Smoking subjects with this lean phenotype in early adulthood deserve particular attention as they seem to develop more severe COPD

    Microbiological and chemical monitoring of Marsala base wine obtained by spontaneous fermentation during large-scale production

    Get PDF
    The present work was undertaken to evaluate the effect of the natural winemaking on the microbial and chemical composition of Marsala base wine. To this purpose, a large-scale vinification process of Grillo grape cultivar was monitored from harvesting to the final product. Total yeasts (TY) showed a rapid increase after must pressing and reached values almost superimposable to those registered during the conventional winemakings. Lactic acid bacteria (LAB) were registered at the highest levels simultaneously to yeast growth at the beginning of the process. Saccharomyces cerevisiae was the species found at the highest concentrations in all samples analysed. Several strains (n= 16) was registered at high levels during the alcoholic fermentation and/or aging of wine; only two of them were detected on the grape surface. Lactobacillus plantarum was the LAB species most frequently isolated during the entire vinification process. Ethanol content was approximately 14% (v/v) at the end of vinification. The value of pH did not greatly vary during the process and the volatile acidity (VA) was detected at low concentrations during the entire transformation. The concentration of malic acid rapidly decreased during the AF; on the other hand, lactic acid showed an irregular trend during the entire process. trans-caffeil tartaric acid was the most abundant hydroxycinnamoyl tartaric acid and volatile organic compounds (VOC) were mainly represented by isoamylic alcohol and isobutanol

    Genomic characterization of individuals presenting extreme phenotypes of high and low risk to develop tobacco-induced lung cancer

    Get PDF
    Single nucleotide polymorphisms (SNPs) may modulate individual susceptibility to carcinogens. We designed a genome-wide association study to characterize individuals presenting extreme phenotypes of high and low risk to develop tobacco-induced non-small cell lung cancer (NSCLC), and we validated our results. We hypothesized that this strategy would enrich the frequencies of the alleles that contribute to the observed traits. We genotyped 2.37 million SNPs in 95 extreme phenotype individuals, that is: heavy smokers that either developed NSCLC at an early age (extreme cases); or did not present NSCLC at an advanced age (extreme controls), selected from a discovery set (n=3631). We validated significant SNPs in 133 additional subjects with extreme phenotypes selected from databases including >39,000 individuals. Two SNPs were validated: rs12660420 (p(combined)=5.66x10(-5); ORcombined=2.80), mapping to a noncoding transcript exon of PDE10A; and rs6835978 (p(combined)=1.02x10(-4); ORcombined=2.57), an intronic variant in ATP10D. We assessed the relevance of both proteins in early-stage NSCLC. PDE10A and ATP10D mRNA expressions correlated with survival in 821 stage I-II NSCLC patients (p=0.01 and p<0.0001). PDE10A protein expression correlated with survival in 149 patients with stage I-II NSCLC (p=0.002). In conclusion, we validated two variants associated with extreme phenotypes of high and low risk of developing tobacco-induced NSCLC. Our findings may allow to identify individuals presenting high and low risk to develop tobacco-induced NSCLC and to characterize molecular mechanisms of carcinogenesis and resistance to develop NSCLC

    Histone H2A (H2A.X and H2A.Z) Variants in Molluscs: Molecular Characterization and Potential Implications For Chromatin Dynamics

    Get PDF
    Histone variants are used by the cell to build specialized nucleosomes, replacing canonical histones and generating functionally specialized chromatin domains. Among many other processes, the specialization imparted by histone H2A (H2A.X and H2A.Z) variants to the nucleosome core particle constitutes the earliest response to DNA damage in the cell. Consequently, chromatin-based genotoxicity tests have been developed in those cases where enough information pertaining chromatin structure and dynamics is available (i.e., human and mouse). However, detailed chromatin knowledge is almost absent in most organisms, specially protostome animals. Molluscs (which represent sentinel organisms for the study of pollution) are not an exception to this lack of knowledge. In the present work we first identified the existence of functionally differentiated histone H2A.X and H2A.Z variants in the mussel Mytilus galloprovincialis (MgH2A.X and MgH2A.Z), a marine organism widely used in biomonitoring programs. Our results support the functional specialization of these variants based on: a) their active expression in different tissues, as revealed by the isolation of native MgH2A.X and MgH2A.Z proteins in gonad and hepatopancreas; b) the evolutionary conservation of different residues encompassing functional relevance; and c) their ability to confer specialization to nucleosomes, as revealed by nucleosome reconstitution experiments using recombinant MgH2A.X and MgH2A.Z histones. Given the seminal role of these variants in maintaining genomic integrity and regulating gene expression, their preliminary characterization opens up new potential applications for the future development of chromatin-based genotoxicity tests in pollution biomonitoring programs

    Mortality prediction in chronic obstructive pulmonary disease comparing the GOLD 2015 and GOLD 2019 staging: a pooled analysis of individual patient data

    Get PDF
    In 2019, The Global Initiative for Chronic Obstructive Lung Disease (GOLD) modified the grading system for patients with COPD, creating 16 subgroups (1A–4D). As part of the COPD Cohorts Collaborative International Assessment (3CIA) initiative, we aim to compare the mortality prediction of the 2015 and 2019 COPD GOLD staging systems. We studied 17 139 COPD patients from the 3CIA study, selecting those with complete data. Patients were classified by the 2015 and 2019 GOLD ABCD systems, and we compared the predictive ability for 5-year mortality of both classifications. In total, 17 139 patients with COPD were enrolled in 22 cohorts from 11 countries between 2003 and 2017; 8823 of them had complete data and were analysed. Mean±sd age was 63.9±9.8 years and 62.9% were male. GOLD 2019 classified the patients in milder degrees of COPD. For both classifications, group D had higher mortality. 5-year mortality did not differ between groups B and C in GOLD 2015; in GOLD 2019, mortality was greater for group B than C. Patients classified as group A and B had better sensitivity and positive predictive value with the GOLD 2019 classification than GOLD 2015. GOLD 2015 had better sensitivity for group C and D than GOLD 2019. The area under the curve values for 5-year mortality were only 0.67 (95% CI 0.66–0.68) for GOLD 2015 and 0.65 (95% CI 0.63–0.66) for GOLD 2019
    corecore