D-mannose transport and metabolism in isolated enterocytes

D-mannose transport and metabolism has been studied in enterocytes isolated from chicken small intestine. In the presence of Na+, the mannose taken up by the cells either remains free, is phosphorylated, is catabolized to H2O, or becomes part of membrane components. The mannose remaining free in the cytosol is released when the cells are transferred to an ice bath. The Na+-dependent D-mannose transport is electrogenic and inhibited by ouabain and dinitrophenol; its substrate specificity differs from SGLT-1 transporter. The Glut2 transporter inhibitors phloretin and cytochalasin B added following 30-min mannose uptake reduced the previously accumulated D-mannose, whereas these two agents increased the cell to external medium 3-O-methyl-glucose (3-OMG) concentration ratio. D-mannose efflux rate from preloaded D-[2-3H]-mannose enterocytes is Na+-independent. Phloretin did not affect D-mannose efflux rate, whereas it inhibited that of 3-OMG. Neither mannose uptake nor efflux rate were affected by fructose. It is concluded that part of the mannose taken up by the enterocytes is rapidly metabolized and that enterocytes have two D-mannose transport systems: one is concentrative and Na+-dependent and the other is Na+-independent and passive.Dirección General de Investiagación Científica y Técnica PM99-012

Aprendizaje basado en competencias: una propuesta para la autoevaluación del docente

Al incorporarse la universidad española Espacio Europeo de Educación superior (EEES) ha llevado aparejados diversos y profundos cambios. Entre estos cambios importantes se encuentra la apuesta decidida por orientar la atención de los procesos formativos en el aprendizaje de los estudiantes y, más concretamente, en los resultados del aprendizaje, medidos a través de las competencias. En el presente artículo hemos planteamos la necesidad de cambiar los procesos de evaluación. Con tal finalidad, hemos partido de la conceptualización de las competencias, hemos analizado las implicaciones de las competencias en la docencia del profesorado y finalmente hemos determinado las características que debiera tener una evaluación por competencias con el objetivo de presentar una herramienta de autoevaluación del proceso de enseñanza-aprendizaje. En este trabajo cuando hablamos de evaluación de competencias nos vamos a referir por una parte a las competencias de aprendizaje del alumno y por otra a las competencias de enseñanza del profesor

Temporal response to drought stress in several Prunus rootstocks and wild species

Prunus species are important crops in temperate regions. In these regions, drought periods are predicted to occur more frequently due to climate change. In this sense, to reduce the impact of climate warming, obtaining new tolerant/resistant cultivars and rootstocks is a mandatory goal in Prunus breeding. Therefore, the current study assembled three Prunus species including almond, (P. dulcis Mill D.A. Webb), apricot (P. armeniaca L.) and peach (P. persica L.) to model the temporal effects of drought. A hybrid peach × almond and a wild almond-relative species Prunus webbii were also included in the study. Physiological traits associated with photosynthetic activity, leaf water status, and chlorophyll content were assessed under three watering treatments. Results showed that effects of time, genotype, and treatment interact significantly in all traits. In addition, results confirmed that P. webbii have a greater tolerance to drought than commercial rootstocks. However, “Real Fino” apricot showed the fastest recovery after re-irrigation while being one of the most affected cultivars. In addition, from the better response to these watering treatments by the almond genotypes, two different trends were observed after re-irrigation treatment that clearly differentiate the response of the almond cultivar “Garrigue” from the rest of Prunus genotypes. A better characterization of the short-term drought response in Prunus, an accurate and more efficient evaluation of the genotype effect was obtained from the use of mixed models considering appropriate variance–covariance structures. Although the advantages of these approaches are rarely used in Prunus breeding, these methodologies should be undertaken in the future by breeders to increase efficiency in developing new breeding materials.info:eu-repo/semantics/publishedVersio

Reseñas

Se reseñan los siguientes libros: * Mateo Alemán, La obra completa, 3 vols., Pedro M. Piñero Ramírez y Katharina Niemeyer (dirs.), Madrid-Frankfurt, Iberoamericana – Vervuert – Junta de Andalucía – Universidad de Sevilla, 2014, 2358 pp. * Lope de Vega, Romances de juventud, ed. Antonio Sánchez Jiménez, Madrid: Cátedra, 2015, 429 pp. * Joan Oleza, Trazas y bazas de la Modernidad. Ensayos desde el cambio cultural. La Plata, Ediciones del lado de acá, 2012, 415 pp. * José del Valle (ed.), A political history of Spanish: the making of a language, Cambridge: Cambridge University Press, [2013] 2015, 430 pp. * Nora Catelli, Juan Benet. Guerra y literatura, Madrid: Libros de la Resistencia, 2016, 160 pp.Facultad de Humanidades y Ciencias de la Educación (FAHCE

Na+-dependent D-mannose transport at the apical membrane of rat small intestine and kidney cortex

The presence of a Na+/D-mannose cotransport activity in brush-border membrane vesicles (BBMV), isolated from either rat small intestine or rat kidney cortex, is examined. In the presence of an electrochemical Na+ gradient, but not in its absence, D-mannose was transiently accumulated by the BBMV. D-Mannose uptake into the BBMV was energized by both the electrical membrane potential and the Na+ chemical gradient. D-Mannose transport vs. external D-mannose concentration can be described by an equation that represents a superposition of a saturable component and another component that cannot be saturated up to 50 μM D-mannose. D-Mannose uptake was inhibited by D-mannose ≫ D-glucose > phlorizin, whereas for α-methyl glucopyranoside the order was D-glucose = phlorizin ≫ D-mannose. The initial rate of D-mannose uptake increased as the extravesicular Na+ concentration increased, with a Hill coefficient of 1, suggesting that the Na+ :D-mannose cotransport stoichiometry is 1:1. It is concluded that both rat intestinal and renal apical membrane have a concentrative, saturable, electrogenic and Na+-dependent D-mannose transport mechanism, which is different from SGLT1.Dirección General de Investigaciones Científicas y Técnicas PM99-012

Fragment dissolved molecular dynamics: a systematic and efficient method to locate binding sites

Diverse computational methods to support Fragment-based drug discovery (FBDD) are available in the literature. Despite their demonstrated efficacy to support FBDD campaigns, they exhibit some drawbacks such as protein denaturation or ligand aggregation that have not been yet clearly overcome in the framework of biomolecular simulations. In the present work, we discuss a systematic semi-automatic novel computational procedure, designed to surpass these difficulties. The method, named fragment dissolved Molecular Dynamics (fdMD) utilizes simulation boxes of solvated small fragments, adding a repulsive Lennard-Jones potential term to avoid aggregation, which can be easily used to solvate the targets of interest. This method has the advantage of solvating the target with a low number of ligands, thus preventing this way denaturation of the target, while simultaneously generating a database of ligandsolvated boxes that can be used in further studies. A number of scripts are made available to analyze the results and obtain the descriptors proposed as a means of trustfully discard spurious binding sites. To test our method, four Test cases of different complexity have been solvated with ligand boxes and four molecular dynamics runs of 200 ns length have been run for each system, which have been extended up to 1 µs when needed. The reported results point that the selected number of replicas are enough to identify the correct binding sites irrespective of the initial structure, even in the case of proteins having several close binding sites for the same ligand. We also propose a set of descriptors to analyze the results, among which, the average MMGBSA and the average KDEEP energies emerge as the most robust ones.Peer ReviewedPostprint (author's final draft

Radiative Heat Transfer for Curvilinear Surfaces

Curved surfaces have not been thoroughly considered in radiative transfer analysis mainly due to the difficulties arising from the integration process and perhaps because of the lack of spatial vision of researchers. When dealing with them, application of the iterative method or direct calculation through integration does not provide with an exact solution, so that only approximate expressions or tables are given for a very limited number of forms. In this way, a vast repertoire of significant shapes remains neglected and energy waste is evident. For this reason, further research on the matter, starting from a different approach was considered worth doing. In previous researches from the authors, form factor calculation has been undertaken for several types of emitters. In all cases, geometric properties of those, revealed as the most powerful tool that shapes radiant interchange. This included mainly rectangular shapes, plane forms and the volumes that can be composed with such primary geometries

Basement structure of the Hontomín CO2 storage site (Spain) determined by integration of microgravity and 3D seismic data

We dedicate this paper to the memory of Prof. Andres Perez Estaún, who was a great and committed scientist, wonderful colleague and even better friend. The datasets in this work have been funded by Fundación Ciudad de la Energía (Spanish Government, www.ciuden.es) and by the European Union through the “European Energy Programme 15 for Recovery” and the Compostilla OXYCFB300 project. Dr. Juan Alcalde is currently funded by NERC grant NE/M007251/1. Simon Campbell and Samuel Cheyney are acknowledged for thoughtful comments on gravity inversionPeer reviewedPublisher PD

Producto orgánico potenciador de la persistencia de atrazina en suelo y bioestimulante edafológico

Producto orgánico potenciador de la persistencia de atrazina en suelo y bioestimulante edafológico. La presente invención tiene por objeto un preparado líquido compuesto por una disolución a partes iguales de un extracto enzimático vegetal y un producto humectante a la que se añade atrazina en polvo hasta obtener una suspensión uniforme del 50% P/V. El producto final es un producto fitosanitario con mayor actividad herbicida y fertilizante ya que aumenta la persistencia de la atrazina e induce la fertilidad química y biológica del suelo.Españ

A comparison of the First View of GPM with Ground Radar and NWCSAF CRPh over Continental Spain

Póster presentado en NWCSAF 2015 Users Workshop. 24-26 de febrero de 2015, MadridThe first, preliminary, data from the Global Precipitation Measurement Core Satellite illustrate the potential of this spacecraft for science and societal applications. Here we show a glimpse on the first overpasses over Spain. The DPR measurements and the GMI estimates area qualitatively compared with Ground Radar (GR) measurements from the National Radar Network of Spain (PPI); with EUMESAT NWCSAF Convective Rainfall Rate from Cloud Physical Properties (CRPh, based on VIS and IR: day-only product); and with Meteosat imagery (HRV and 10.8 mm IR channels from MSG). Notwithstanding the provisional character of the data and all the applicable caveats and isclaimers, both the GPM radar and the radiometer provide precipitation estimates that are remarkably close to ground radar observations. This is specially noticeable for the GMI, as the estimates used here come from the original, day-1 database. Also CRPh product shows a good behavior in all cases. The adequacy of using GPM data to calibrate/validate the NWCSAF CRPh product is being studied