362 research outputs found

    Autophagy is activated and involved in cell death with participation of cathepsins during stress-induced microspore embryogenesis in barley

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    Microspores are reprogrammed towards embryogenesis by stress. Many microspores die after this stress, limiting the efficiency of microspore embryogenesis. Autophagy is a degradation pathway that plays critical roles in stress response and cell death. In animals, cathepsins have an integral role in autophagy by degrading autophagic material; less is known in plants. Plant cathepsins are papain-like C1A cysteine proteases involved in many physiological processes, including programmed cell death. We have analysed the involvement of autophagy in cell death, in relation to cathepsin activation, during stress-induced microspore embryogenesis in Hordeum vulgare. After stress, reactive oxygen species (ROS) and cell death increased and autophagy was activated, including HvATG5 and HvATG6 up-regulation and increase of ATG5, ATG8, and autophagosomes. Concomitantly, cathepsin L/F-, B-, and H-like activities were induced, cathepsin-like genes HvPap-1 and HvPap-6 were up-regulated, and HvPap-1, HvPap-6, and HvPap-19 proteins increased and localized in the cytoplasm, resembling autophagy structures. Inhibitors of autophagy and cysteine proteases reduced cell death and promoted embryogenesis. The findings reveal a role for autophagy in stress-induced cell death during microspore embryogenesis, and the participation of cathepsins. Similar patterns of activation, expression, and localization suggest a possible connection between cathepsins and autophagy. The results open up new possibilities to enhance microspore embryogenesis efficiency with autophagy and/or cysteine protease modulators.España, MINECO AGL2014-52028-R and AGL2017-82447-

    Theoretical study of the effect of substituent and backbone conformation on the electronic properties of symmetrically substituted poly(di‐n‐alkylsilanes)

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    We present the results of ab initio 3‐21G∗ geometry optimizations and valence effective Hamiltonian (VEH) band structure calculations aimed at determining the evolution of the geometric and electronic (ionization potential, electron affinities, and band gaps) properties of all‐trans poly(dimethylsilane), poly(diethylsilane), poly(di‐n‐propylsilane), and poly(di‐n‐butylsilane) when increasing the size of the alkyl group. In the latter polymer, we have also studied the 7/3 conformation, in order to analyze the effect of the backbone conformation on the geometric and electronic structure. The VEH ionization potentials of all‐trans poly(di‐n‐alkylsilanes) are almost equal, and as experimental photoemission data show, only slight differences are appreciated. The band gap decreases in going from poly(di‐n‐butylsilane) to poly(di‐n‐propylsilane) and to poly(diethylsilane), and increases when passing to poly(dimethylsilane), which coincides with experimental evidences on poly(di‐n‐alkylsilanes). The change from all‐trans to 7/3 conformation of poly(di‐n‐butylsilane) implies an increase of both, ionization potential and band gap, in perfect agreement with experimental photoemission and absorption data. The applicability of VEH to deal with poly(di‐n‐alkylsilanes) is [email protected]

    The educational e-portfolio: preliminary evidence of its relationship with student\u2019s self-efficacy and engagement

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    The educational use of portfolios has been increasing in the last few years, especially as technology has also developed electronic versions of portfolios. Although there is abundant information about their benefits and practice description, few studies provide empirical evidence of their implementation. The objective of this study was to provide initial evidence about the use of the portfolio in higher education. Concretely, we aimed 1) to explore the correlation between students’ performance on the portfolio and their performance on more traditional assessment methods 2) to explore whether student’s personal variables predict performance in key elements of the e-portfolio, such as individual reflections, and if these contribute to general academic performance in the course, and 3) to evaluate whether the use of the e-portfolio during a semester changes the students’ self-efficacy and engagement. For this purpose, an initial sample of 73 students were recruited, and an e-portfolio (based on Mahara) was implemented over a semester. The results showed that performance on the portfolio correlated with the score obtained on multiple choice tests. There was an increase in self-efficacy after one semester of e-portfolio implementation, and engagement proved to be an important predictor of the final course grade through the mediation of individual reflections. These results offer preliminary and promising evidence about the relationship of a specific element of e-portfolios, individual reflections with several variables related to academic achievement such as self-efficacy and engagement

    Active methodologies for deep learning in sustainable development goals

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    [EN] The general objective of this project was to improve the quality of student learning, from the point of view of a global objective, sustainable development, and therefore aligned with the SDGs (Sustainable Development Goals). It is intended that students achieve deep learning in this area, favouring the transfer of the knowledge acquired to their future professional and social life. This deep learning promotes the integral development of the student, not only from an academic point of view, but also social and ecological. Project Based Learning (PBL), as an active learning methodology, is being widely used as a deep learning strategy. In this project, it has been used in several subjects, from different degrees, schools, and campus. The learning strategies have been evaluated by means of a learning evaluation questionnaire (CEVEAPEU) before and after the application of the PBL. In addition, student satisfaction and generic skills (i.e. ethical, environmental and professional responsibility) have been assessed. The project aims to find a solution a specific real case, such as an environmental or social problem. The results show that PBL has favoured the cooperative work of students and has increased their motivation. The students could select the topics that interest them the most and that they consider important in their professional future. They have worked collaboratively and actively, planning the project, making decisions, implementing it, and evaluating it. The students have ¿acted¿ and the teachers have been advisors or guides, thus promoting intrinsic motivation. This active methodology has allowed students to learn in a collaborative and cooperative way, fostering their motivation and achieving deep learning in environmental aspects.The project of innovation and educational improvement in which this communication is framed has received financial support from the Institute of Education Sciences (ICE) of the Universitat Politècnica de València (UPV) Proyecto de Innovación y Mejora Educativa (PIME/19-20/174 ), Objetivo Agenda 2030 y UPV 2020: Aprendizaje ambiental profundo en la UPV.Romero Gil, I.; Paches Giner, MAV.; Sebastiá-Frasquet, M.; Hernández Crespo, C. (2021). Active methodologies for deep learning in sustainable development goals. IATED Academy. 5506-5513. https://doi.org/10.21125/inted.2021.1115S5506551

    Human hydroxytyrosol's absorption and excretion from a nutraceutical

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    Among the various (poly)phenols that are being sold as such or as part of a more complex mixture, hydroxytyrosol (HT) is the only one that bears a European Food Safety Authority health claim. Therefore, several HT-based products are being developed and sold and it becomes necessary to evaluate its accessibility following ingestion. Twenty-one volunteers were recruited for a randomized, crossover, placebo-controlled, and double-blind intervention study.We performed a Latin square design: after one-week washout, i.e. olive-free diet, subjects were randomly assigned to the placebo (maltodextrin), 5, or 25 mg/day HT group. Twenty-four hour urine samples were collected after the intervention week, and baseline urines were collected the week before the study and during periods of washout. The results show that HT given as the foremost component of a nutraceutical preparation is bioavailable and is recovered in the urine chiefly as sulphate-3′

    Una Herramienta para el Aprendizaje del Álgebra Relacional

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    El estudio de las bases de datos relacionales forma parte del currículum de los estudios de Ingeniería Técnica Informática. Los lenguajes de consulta abstractos, entre ellos el Álgebra Relacional, forman una parte importante de este estudio, pero nuestra experiencia docente nos ha demostrado que, para los alumnos, es difícil conocer cuándo las consultas expresadas en un papel en términos de estos lenguajes son correctas y responden a los requisitos de información planteados. En este trabajo se describe una herramienta de apoyo que se ha desarrollado en la Universidad de Valladolid que permite realizar consultas expresadas en Álgebra Relacional sobre cualquier base de datos. El alumno puede explorar, así, las diferentes posibilidades de este lenguaje abstracto, comprobando por sí mismo la calidad de su aprendizaje. La herramienta ha sido desarrollada siguiendo guías metodológicas propugnadas en el ámbito del diseño de entornos de aprendizaje

    Thermodynamic characterization of deep eutectic solvents at high pressures

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    Despite the large spectrum of applications being reported for DESs over the last decade, their thermodynamic characterization is often neglected, hindering a better understanding of their nature, and the development of accurate and robust thermodynamic models to describe them, essential for the conceptual and design stages of new industrial processes. This work aims at decreasing such a gap in literature by reporting new experimental density and viscosity data in wide temperature and pressure ranges for the three archetypal DESs of cholinium chloride, as hydrogen bond acceptor, combined with either ethylene glycol, glycerol, or urea, as hydrogen bond donor. The experimental data measured in this work were then correlated using the Perturbed Chain - Statistical Associating Fluid Theory equation of state coupled with the Free Volume Theory to assess the performance of existing coarse-grained models when applied to the description of DESs. The modelling results obtained highlight the limitation of the existing models, since a correct prediction of DES density could not be achieved, reinforcing the need for viable alternative approaches for the development of coarse-grained models that are appropriate for the thermodynamic modelling of DESs.publishe

    Stem cells from human cardiac adipose tissue depots show different gene expression and functional capacities

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    Altres ajuts: This work was supported by grants from FEDER "Una Manera de Hacer Europa"; the Secretary of University and Research. We thank FIC-Fundacion Jesús Serra, Barcelona, Spain, for their continuous support.Background: The composition and function of the adipose tissue covering the heart are poorly known. In this study, we have investigated the epicardial adipose tissue (EAT) covering the cardiac ventricular muscle and the EAT covering the left anterior descending artery (LAD) on the human heart, to identify their resident stem cell functional activity. Methods: EAT covering the cardiac ventricular muscle was isolated from the apex (avoiding areas irrigated by major vessels) of the heart (ventricular myocardium adipose tissue (VMAT)) and from the area covering the epicardial arterial sulcus of the LAD (PVAT) in human hearts excised during heart transplant surgery. Adipose stem cells (ASCs) from both adipose tissue depots were immediately isolated and phenotypically characterized by flow cytometry. The different behavior of these ASCs and their released secretome microvesicles (MVs) were investigated by molecular and cellular analysis. Results: ASCs from both VMAT (mASCs) and the PVAT (pASCs) were characterized by the expression of CD105, CD44, CD29, CD90, and CD73. The angiogenic-related genes VEGFA, COL18A1, and TF, as well as the miRNA126-3p and miRNA145-5p, were analyzed in both ASC types. Both ASCs were functionally able to form tube-like structures in three-dimensional basement membrane substrates. Interestingly, pASCs showed a higher level of expression of VEGFA and reduced level of COL18A1 than mASCs. Furthermore, MVs released by mASCs significantly induced human microvascular endothelial cell migration. Conclusion: Our study indicates for the first time that the resident ASCs in human epicardial adipose tissue display a depot-specific angiogenic function. Additionally, we have demonstrated that resident stem cells are able to regulate microvascular endothelial cell function by the release of MVs

    CVS-Q teen©: computer vision syndrome in adolescents and its relationship with digital textbooks

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    Objetivo: Analizar la prevalencia y la evolución del síndrome visual informático en estudiantes de secundaria y bachillerato mediante el CVS-Q© adaptado y validado para adolescentes, según empleen libros en papel o en soporte digital. Método: Se adaptará el CVS-Q© mediante un pilotaje en adolescentes y un grupo nominal compuesto por especialistas en salud visual, profesorado y padres/madres. Se evaluarán la calidad y la aplicabilidad de la versión resultante (CVS-Q teen©) y se realizará un estudio de validación con pruebas visuales, retest y análisis psicométrico. Posteriormente, se realizará un estudio prospectivo longitudinal con cuatro medidas repetidas en adolescentes de dos institutos de San Juan de Alicante (uno ha sustituido libros por tabletas). Se medirá el síndrome visual informático mediante el CVS-Q teen© con tres seguimientos. Se analizará la prevalencia de síndrome visual informático según factores sociodemográficos, visuales y de uso de dispositivos digitales. Se realizarán modelos de regresión logística con efecto aleatorio por estudiante y tiempo de uso.Objective: To analyse the prevalence and progression of computer vision syndrome in secondary and high school students with the CVS-Q© adapted and validated for adolescents, depending on whether they use textbooks or digital books. Method: The CVS-Q© will be adapted by a pilot study in adolescents and a nominal group of visual health specialists, teachers and parents. The resulting version (CVS-Q teen©) will be tested to confirm its quality and applicability and a validation study will be done with visual tests, retest and psychometric analysis. Subsequently, a prospective longitudinal study with four repeated measures will be carried out in adolescents from two secondary schools of San Juan de Alicante (one has replaced textbooks by tablets). Computer vision syndrome will be measured by the CVS-Q teen© with three follow-ups. The prevalence of computer vision syndrome will be analysed according to sociodemographic, visual and digital device use variables. Logistic regression models will be performed, with random effect by student and time of use.Los autores agradecen al Vicerrectorado de Investigación de la Universidad de Alicante por el contrato de formación predoctoral de la segunda autora (UAFPU2019-08). El presente proyecto ha sido financiado por la convocatoria «Proyectos de Investigación en Salud», Fondo de Investigación en Salud del Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación y Unión Europea, a través de los Fondos Europeos de Desarrollo Regional (FEDER) «Una manera de hacer Europa», con la referencia PI20/01629
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