The Grothendieck and Picard groups of finite rank torsion free {sl}(2)-modules

[EN] The classification problem for simple sl(2)-modules leads in a natural way to the study of the category of finite rank torsion free sl(2)-modules and its subcategory of rational sl(2)-modules. We prove that the rationalization functor induces an identification between theisomorphism classes of simple modules of these categories. This raises the question of what is the precise relationship between other invariants associated with them. We give a complete solution to this problem for the Grothendieck and Picard groups, obtaining along the way several new results regarding these categories that are interesting in their own right.Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCLE

Heat Stress in Rat Adriamycin Cardiomyopathy: Heat Shock Protein 25 and Myosin Accumulation

In order to evaluate the effects of hyperthermia on adriamycin cardiomyopathy and its relationship with heat shock protein induction and myosin accumulation, female Sprague-Dawley rats (21–24 days) were randomized into four groups: the control, adriamycin, temperature and temperature-adriamycin groups. Adriamycin was injected i.v. at a dose of 27 mg/Kg (0.1 ml). The rats were exposed to a temperature of 45ºC for 35 min, followed by a recovery (1 h) at room temperature prior to adriamycin treatment. Body weight was recorded weekly. The thickness of the ventricular wall and percentage of cellular damage were biometrically and ultrastructurally evaluated, respectively. Heat shock protein 25 and myosin accumulation were determined through Western blot analysis. The determinations were carried out monthly until the third month after treatment. At eight and twelve weeks after treatment, the thickness of the ventricular wall seemed to decrease in the adriamycin-treated rats in relation to the other groups. An electron microscopic analysis of the adriamycin group’s left ventricular wall samples, showed more sarcomeric changes and loss of myofibrils than the control, temperature and temperature-adriamycin groups. At 24 hours after treatment with adriamycin, higher levels of heat shock protein 25 and myosin were observed (week 0) in the temperature-adriamycin group than in the control and adriamycin groups (4, 8 and 12 weeks). Hyperthermia was confirmed by a multivariate approach to induce heat shock protein 25 and myosin, which would strengthen cardiac-sarcomeric myosin arrangement

Natural operations on holomorphic forms

Demostramos que las únicas operaciones diferenciales naturales entre las formas holomórficas en una variedad compleja son las que se obtienen usando combinaciones lineales, el producto exterior y el diferencial exterior. Para llevar a cabo esta tarea, primero desarrollamos los fundamentos de la teoría de los haces holomórficos naturales sobre una variedad fija, haciendo explícita su estructura galoisiana al probar una equivalencia categórica a la Galois.We prove that the only natural differential operations between holomorphic forms on a complex manifold are those obtained using linear combinations, the exterior product and the exterior differential. In order to accomplish this task we first develop the basics of the theory of natural holomorphic bundles over a fixed manifold, making explicit its Galoisian structure by proving a categorical equivalence à la Galois.• Ministerio de Economía y Competitividad. Proyecto ICMAT Severo Ochoa SEV-2015-0554, para Alberto Navarro Garmendia • Ministerio de Economía y Competitividad. Proyecto MTM2013-42135-P (I+D+i), para Alberto Navarro Garmendia • Ministerio de Economía y Competitividad. Proyecto ANR-12-BS01-0002 (I+D+i), para Alberto Navarro Garmendia • Junta de Extremadura y Fondos FEDER. Ayuda, para para José Navarro Garmendia • Ministerio de Economía y Competitividad. Proyecto MTM2013-42135-P (I+D+i), para Tomás Carlos Tejero PrietopeerReviewe

Infección por SARS-COV-2 durante la gestación: factores de riesgo, manifestaciones clínicas y resultados perinatales.

Introducción. Al inicio de la pandemia de COVID-19, el alcance exacto de los riesgos en la gestación era incierto. Por ello, estudios sobre el impacto del COVID-19 y de la pandemia en la gestación han sido necesarios.Objetivo. Evaluar el riesgo de resultado perinatal adverso y de complicaciones obstétricas en gestantes diagnosticadas de COVID-19 durante la gestación. Evaluar el impacto del año 2020 en los resultados perinatales.Material y métodos. Estudio observacional analítico de cohortes realizado en el servicio de Ginecología y Obstetricia del Hospital Clínico Universitario Lozano Blesa (Zaragoza).En este estudio hemos analizado las complicaciones obstétricas y los resultados perinatales de las gestantes con infección por COVID-19 confirmada (n=135) (por olas, por trimestres y por gravedad) y además hemos comparado dichos resultados con un grupo de gestantes no expuestas al COVID-19 durante la pandemia (n=2002) y otro grupo de gestante no expuestas al COVID-19 pre-pandemia (n=29048).Resultados. De las 135 gestantes, la mayoría de los contagios tuvieron lugar en el 3º trimestre y solo un 5,2% presentó sintomatología severa-crítica. Las gestantes expuestas a COVID-19 tuvieron casi 6 veces más riesgo de presentar trastornos hipertensivos del embarazo y aproximadamente 9 veces más riesgo de presentar preeclampsia; independientemente de la severidad de la infección. Sin embargo, no se objetivaron diferencias en otras patologías como la prematuridad o el retraso de crecimiento intrauterino. En el año 2020, tanto en gestantes expuestas como en no expuestas, se ha observado un incremento significativo de los trastornos hipertensivos (5,5%), de la preclampsia (2,5%) y de la mortalidad fetal (8,5 por mil) con respecto a los últimos años. Sin embargo, de nuevo, la prematuridad y la restricción del crecimiento fetal se han mantenido estables. Conclusiones. La infección por COVID-19 se asocia con un mayor riesgo de trastornos hipertensivos durante la gestación, independientemente de la severidad de la infección. El año 2020 ha registrado la incidencia más alta de preeclampsia y de muerte fetal de los últimos 13 años en nuestro centro. Palabras clave: SARS-COV-2, COVID-19, coronavirus, infección, embarazo.<br /

Acyl Group Migration in Pyranosides as Studied by Experimental and Computational Methods

Acyl group migration affects the synthesis, isolation, manipulation and purification of all acylated organic compounds containing free hydroxyl groups, in particular carbohydrates. While several isolated studies on the migration phenomenon in different buffers have been reported, comprehensive insights into the overall migration process in different monosaccharides under similar conditions have been lacking. Here, we have studied the acyl migration in different monosaccharides using five different acyl groups by a combination of experimental, kinetic and theoretical tools. The results show that the anomeric configuration in the monosaccharide has a major influence on the migration rate, together with the relative configurations of the other hydroxyl groups and the nature of the migrating acyl group. Full mechanistic model, based on computations, demonstrates that the acyl migration proceeds through an anionic stepwise mechanism with linear dependence on the OH-] and the pK(a) of the hydroxyl group toward which the acyl group is migrating

Acetyl Group Migration in Xylan and Glucan Model Compounds as Studied by Experimental and Computational Methods

It was recently demonstrated by us that acetyl groups in oligosaccharides can migrate not only within one saccharide unit but also between two different saccharide units. Kinetics of this phenomenon were previously investigated in both mannan model compounds and a naturally occurring polysaccharide. In addition to mannans, there are also several other naturally acetylated polysaccharides, such as xyloglucans and xylans. Both xyloglucans and xylans are some of the most common acetylated polysaccharides in nature, displaying important roles in the plant cells. Considering the various biological roles of natural polysaccharides, it could be hypothesized that the intramolecular migration of acetyl groups might also be associated with regulation of the biological activity of polysaccharides in nature. Consequently, a better understanding of the overall migration phenomenon across the glycosidic bonds could help to understand the potential role of such migrations in the context of the biological activity of polysaccharides. Here, we present a detailed investigation on acetyl group migration in the synthesized xylan and glucan trisaccharide model compounds by a combination of experimental and computational methods, showing that the migration between the saccharide units proceeds from a secondary hydroxyl group of one saccharide unit toward a primary hydroxyl group of the other unit

Computational studies of Brønsted acid-catalyzed transannular cycloadditions of cycloalkenone hydrazones

The contribution to the energy barrier of a series of tethers in transannular cycloadditions of cycloalkenes with hydrazones has been computationally studied by using DFT. The Houk's distortion model has been employed to evaluate the influence of the tether in the cycloaddition reaction. That model has been extended to determine the contribution of each tether and, more importantly, the effect exerted between them. In addition to the distortion induced by the tethers, the entropy effects caused by them has also been studied. The analysis of the evolution of the electron localization function along the reaction revealed the highly concerted character of the reaction

The essential role of water molecules in the reaction mechanism of protein O-Fucosyltransferase 2

Protein O-fucosyltransferase 2 (PoFUT2) is an inverting glycosyltransferase (GT) that fucosylates thrombospondin repeats (TSRs) from group 1 and 2. PoFUT2 recognizes a large and diverse number of TSRs through a dynamic network of water-mediated interactions. By X-ray structural studies of C. elegans PoFUT2 complexed to a TSR of group 2, we demonstrate that this GT recognizes similarly the 3D structure of TSRs from both groups 1 and 2. Its active site is highly exposed to the solvent, suggesting that water molecules might also play an essential role in the fucosylation mechanism. We applied QM/MM methods using human PoFUT2 as a model, and found that HsPoFUT2 follows a classical S(N)2 reaction mechanism in which water molecules contribute to a great extent in facilitating the release of the leaving pyrophosphate unit, causing the H transfer from the acceptor nucleophile (Thr/Ser) to the catalytic base, which is the last event in the reaction. This demonstrates the importance of water molecules not only in recognition of the ligands but also in catalysis

Suivi de l'évolution de la température du couvert végétal de deux variétés soumises a une irrigation déficitaire: un outil pour optimiser la géstion de l'eau ?

A better understanding of grapevine responses to drought and high air temperatures can help to optimize vineyard management to improve water use efficiency, yield and berry quality. Faster and robust field phenotyping tools are needed in modern precision viticulture, in particular in dry and hot regions such as the Mediterranean. Canopy temperature (Tc) is commonly used to monitor water stress in plants/crops and to characterize stomatal physiology in different woody species including Vitis vinifera. Thermography permits remote determination of leaf surface or canopy temperature in the field and also to assess the range and spatial distribution of temperature from different parts of the canopies. Our hypothesis is that grapevine genotypes may show different Tc patterns along the day due to different stomatal behaviour and heat dissipation strategies. We have monitored the diurnal and seasonal course of Tc in two grapevine genotypes, Aragonez (syn. Tempranillo) and Touriga Nacional subjected to deficit irrigation under typical Mediterranean climate conditions. Temperature measurements were complemented by determination of the diurnal course of leaf water potential (ψleaf) and leaf gas exchange. Measurements were done in two seasons (2013 and 2014) at different phenological stages: i) mid-June (green berry stage), ii) mid-July (veraison), iii) early August (early ripening) and iv) before harvest (late ripening). Correlations between Tc and minimal stomatal conductance will be presented for the two genotypes along the day. Results are discussed over the use of thermal imagery to derive information on genotype physiology in response to changing environmental conditions and to mild water stress induced by deficit irrigation. Strategies to optimize the use of thermal imaging in field conditions are also propose

Síntesis asimétrica de compuestos ópticamente activos de importancia biológica y farmacológica

Se quiere encontrar un método eficiente para sintetizar potenciales inhibidores de glicosiltransferasas. Este tipo de compuestos son de gran interés debido a su uso como medicamentos para tratar diversas enfermedades. Se piensa en el grupo funcional nitrona como un buen precursor para la síntesis de este tipo de compuestos, por lo que se sintetizan diferentes nitronas cíclicas de cinco miembros como precursoras del glicomimético que posteriormente usaremos como inhibidor. Se utilizan este tipo de nitronas debido a su parecido comportamiento con los azucares y por lo tanto, cuanto más parecido sea al producto que queremos “mimetizar”, mejores prestaciones tendremos. El grupo funcional nitrona presenta una gran reactividad lo que favorece la elección de este tipo de compuestos. Posterior a esto se le acoplara un conector mediante una adición nucleófila, que nos servirá para anclarle un nucleósido y así poder formar el producto final que será lo que se probara como posible inhibidor de glicosiltransferasas