Extracellular cysteine in connexins: Role as redox sensors

Indexación: Scopus.Connexin-based channels comprise hemichannels and gap junction channels. The opening of hemichannels allow for the flux of ions and molecules from the extracellular space into the cell and vice versa. Similarly, the opening of gap junction channels permits the diffusional exchange of ions and molecules between the cytoplasm and contacting cells. The controlled opening of hemichannels has been associated with several physiological cellular processes; thereby unregulated hemichannel activity may induce loss of cellular homeostasis and cell death. Hemichannel activity can be regulated through several mechanisms, such as phosphorylation, divalent cations and changes in membrane potential. Additionally, it was recently postulated that redox molecules could modify hemichannels properties in vitro. However, the molecular mechanism by which redox molecules interact with hemichannels is poorly understood. In this work, we discuss the current knowledge on connexin redox regulation and we propose the hypothesis that extracellular cysteines could be important for sensing changes in redox potential. Future studies on this topic will offer new insight into hemichannel function, thereby expanding the understanding of the contribution of hemichannels to disease progression.http://journal.frontiersin.org/article/10.3389/fphys.2016.00001/ful

Frecuencias propias y índices de amortiguamiento durante la respuesta de un portico de cuatro pisos en diferentes estados de daño o reparación

Se analizan en este artículo los resultados de los ensayos sísmicos en un pórtico de hormigón armado. A través del método pseudodinámico, el pórtico fue sometido a la acción de varios acelerogramas horizontales con amplitud creciente. Dicho pórtico había sido construido siguiendo un diseño según típicas prácticas constructivas de hace 40 ó 50 años en países europeos mediterráneos. El análisis permite conocer la evolución de la frecuencia propia y el índice de amortiguamiento durante los terremotos gracias a un método de identificación que se aplica en el dominio del tiempo. Estos parámetros así obtenidos se correlacionan con el estado de la estructura y la amplitud de la deformación permitiendo obtener información útil para la predicción de la respuesta en estructuras semejantes.This paper analyses the results of the seismic tests on a reinforced-concrete frame. The frame was submitted to several increasing amplitude accelerograms by means of the pseudodynamic method. That frame had been built following typical design practices of 40 or 50 years ago in European Mediterranean countries. The analysis allows to know the evolution of the eigenfrequency and damping ratio during the earthquakes thanks to an identification method applied in the time domain. Those obtained parameters are correlated with the state of the structure and the amplitude of deformation allowing to obtain useful information for the prediction of the response of similar structures

Novel types of anti-ecloud surfaces

In high power RF devices for space, secondary electron emission appears as the main parameter governing the multipactor effect and as well as the e-cloud in large accelerators. Critical experimental activities included development of coatings with low secondary electron emission yield (SEY) for steel (large accelerators) and aluminium (space applications). Coatings with surface roughness of high aspect ratio producing the so-call secondary emission suppression effect appear as the selected strategy. In this work a detailed study of the SEY of these technological coatings and also the experimental deposition methods (PVD and electrochemical) are presented. The coating-design approach selected for new low SEY coatings include rough metals (Ag, Au, Al), rough alloys (NEG), particulated and magnetized surfaces, and also graphene like coatings. It was found that surface roughness also mitigate the SEY deterioration due to aging processes.Comment: 4 pages, contribution to the Joint INFN-CERN-EuCARD-AccNet Workshop on Electron-Cloud Effects: ECLOUD'12; 5-9 Jun 2012, La Biodola, Isola d'Elba, Italy; CERN Yellow Report CERN-2013-002, pp.153-15

Population genetic structure and colonization sequence of Drosophila subobscura in the Canaries and Madeira Atlantic islands as inferred by autosomal, sex-linked and mtDNA traits

The genetic structure In Atlantic Islands and continental populations of Drosophila subobscura has been studied using autosomal and sex-linked allozymes and ml tochondrial DNA (mtDNA) haplotypes. From the data it Is deduced that whereas the Canary Islands have long been isolated, the neighboring island of Madeira has been subjected to continuous migration from the mainland. In addition, sex-linked allo zymes and mtDNA data show a large divergence between the geologically younger western Islands of the Canarian Archipelago and the older central ones, finding strong founder effects In the former. Divergence rates of sex-linked and mltochon drlal genes relative to autosomlc loci several times higher than expected under neutrality have been explained by differential migration between sexes. The Ca narian Archipelago colonization fits in well with a stepping-stone model of a direc tional east-west migration that parallels the geological origin of these Islands.info:eu-repo/semantics/publishedVersio

P29 274. Indicaciones de la válvula aórtica ats 3f enable® sin sutura

La válvula ATS 3f Enable® (Medtronic) es una prótesis biológica de pericardio, diseñada como una válvula tubular para optimizar sus características hemodinámicas y disminuir el estrés.ObjetivosDescripción de las posibles indicaciones de la válvula aórtica 3f Enable® sin sutura seg?estra experiencia.Material y métodosDesde mayo de 2010 se han implantado 10 válvulas 3f Enable®, eligiendo pacientes con anillo aórtico pequeño (< 21mm) e índice de masa corporal (IMC) igual o superior a 30 o con estenosis protésica de 19mm. El tamaño de los implantes fue: 19mm: 5, 21mm: 4, y 23mm: 1. Perfil clínico de los pacientes: edad media: 72 años. Estenosis aórtica protésica: 2 pacientes. EuroSCORE medio: 6,3. El IMC medio de los pacientes con estenosis nativa: 32. En tres pacientes se realizaron injertos concomitantes.ResultadosTodos los implantes se realizaron con éxito. En dos pacientes fue necesaria la recolocación de la prótesis por insuficiencia antes de descontinuar la circulación extracorpórea. El tiempo medio de isquemia fue de 61 min, con un rango de 22–81 min. Los gradientes pico obtenidos fueron 21±6mmHg y los gradientes medios de 11±3mmHg. Un paciente requirió reintervención por insuficiencia grave debido a inframedición de la prótesis.ConclusionesLa prótesis 3f Enable® presenta un excelente comportamiento hemodinámico en pacientes con anillo aórtico pequeño y con un IMC igual o superior a 30 y consiguiente riesgo de mismatch. La estenosis protésica de 19mm también se podría considerar como indicación de implante de esta válvula

Eficacia del programa «(Des)venturas de Testas» para la promoción de un enfoque profundo de estudio

En este artículo se aporta información sobre la efi cacia de un programa tutorial para la mejora de los procesos de estudio y promoción de enfoques profundos de aprendizaje. El programa «(Des)venturas de Testas» se organiza en torno a un conjunto de libros que relatan las experiencias vividas por Testas, un alumno típico, a lo largo de su escolaridad. Estas historias constituyen la oportunidad para trabajar un amplio repertorio de estrategias de aprendizaje y procesos de autorregulación, pretendiendo capacitar a los alumnos para aprendizajes actuales y futuros más profundos. El programa se llevó a cabo durante un curso académico, una hora semanal en clases de tutoría. El diseño utilizado fue cuasi-experimental, con grupo experimental (n= 50) y grupo control (n= 49), y medidas pre y postest (conocimiento declarativo de estrategias de aprendizaje, enfoques de aprendizaje y rendimiento académico). Los datos obtenidos muestran que los alumnos que participan en el programa de capacitación, en relación a sus compañeros del grupo control, mejoran signifi cativamente en cuanto al dominio de conocimiento declarativo respecto de las estrategias de aprendizaje y del enfoque profundo, y disminuye el uso de un enfoque de estudio superfi cial, aunque no se obtienen mejoras estadísticamente signifi cativas en el rendimiento académico.Effi cacy of the program «Testas’s (mis)adventures» to promote the deep approach to learning. This paper provides information about the effi cacy of a tutorial training program intended to enhance elementary fi fth graders’ study processes and foster their deep approaches to learning. The program «Testas’s (mis) adventures» consists of a set of books in which Testas, a typical student, reveals and refl ects upon his life experiences during school years. These life stories are nothing but an opportunity to present and train a wide range of learning strategies and self-regulatory processes, designed to insure students’ deeper preparation for present and future learning challenges. The program has been developed along a school year, in a one hour weekly tutorial sessions. The training program had a semi-experimental design, included an experimental group (n=50) and a control one (n=50), and used pre- and posttest measures (learning strategies’ declarative knowledge, learning approaches and academic achievement). Data suggest that the students enrolled in the training program, comparing with students in the control group, showed a signifi cant improvement in their declarative knowledge of learning strategies and in their deep approach to learning, consequently lowering their use of a surface approach. In spite of this, in what concerns to academic achievement, no statistically signifi cant differences have been found

Structure and evolution of the mitochondrial DNA complete control region in the Drosophila subobscura subgroup

The complete A + T-rich region of mitochondrial DNA (mtDNA) has been cloned and sequenced in the species of the Drosophila subobscura subgroup D. subobscura, D. madeirensis and D. guanche. Comparative analysis of these sequences with others already published has identified new sequence motifs that are conserved in Drosophila and other insects. A putative bi-directional promoter and a stop signal are proposed to be involved in the primary mtDNA strand replication of Drosophila. This region strongly resolves relationships of the species included in a phylogenetic analysis, both for closely related species and also at deeper phylogenetic levels when only the left and central domains are taken into account.info:eu-repo/semantics/publishedVersio

A label free disposable device for rapid isolation of rare tumor cells from blood by ultrasounds

The use of blood samples as liquid biopsy is a label-free method for cancer diagnosis that offers benefits over traditional invasive biopsy techniques. Cell sorting by acoustic waves offers a means to separate rare cells from blood samples based on their physical properties in a label-free, contactless and biocompatible manner. Herein, we describe a flow-through separation approach that provides an efficient separation of tumor cells (TCs) from white blood cells (WBCs) in a microfluidic device, "THINUS-Chip" (Thin-Ultrasonic-Separator-Chip), actuated by ultrasounds. We introduce for the first time the concept of plate acoustic waves (PAW) applied to acoustophoresis as a new strategy. It lies in the geometrical chip design: different to other microseparators based on either bulk acoustic waves (BAW) or surface waves (SAW, SSAW and tSAW), it allows the use of polymeric materials without restrictions in the frequency of work. We demonstrate its ability to perform high-throughput isolation of TCs from WBCs, allowing a recovery rate of 84%±8% of TCs with a purity higher than 80% and combined viability of 85% at a flow rate of 80 µL/min (4.8 mL/h). The THINUS-Chip performs cell fractionation with low-cost manufacturing processes, opening the door to possible easy printing fabrication

Seasonal and spatial compositional variation of the red algae Mastocarpus stellatus from the Northern coast of Portugal

This study focusses on the valorization of the red seaweed Mastocarpus stellatus, collected in the Northern coast of Portugal, as a natural source of high value compounds due to its beneficial properties. An annual monitoring of the seaweed was performed by determining its lipids, ash, carbohydrates, phycobiliproteins, total phenolic compounds, antioxidant capacity and carrageenan from three different rocky shores located in the north of Portugal. The results showed a seasonal and spatial variability of the studied compounds between October 2018 and September 2019 depending on the climatic variables of temperature, precipitation, and solar radiation. The most productive season coincided with the warmest months, except for carbohydrates and phycobiliproteins, which were promoted in the colder season. The spatial variation also could be explained by the proximity to water channel discharges at the sampling sites. Complementary studies on the carrageenan fraction were conducted in one of the shores due to the high biopolymer content, to determine their carrageenan proportion between the summer and winter period and establish their rheological capabilities for the formulation of gelling matrices. The extracted biopolymers exhibited typical structural and viscoelastic characteristics of kappa/iota-hybrid carrageenans, suggesting notably differences depending on the harvest season, which is critically relevant to define future applications.Agencia Estatal de Investigación | Ref. RYC2018-024454-IXunta de Galicia | Ref. ED431F 2020/01Fundação para a Ciência e a Tecnologia | Ref. UIDP/04423/2020Fundação para a Ciência e a Tecnologia | Ref. UIDB/04423/2020Universidade de Vigo/CISU

Synthesis, Fungitoxic Activity against Botrytis cinerea and Phytotoxicity of Alkoxyclovanols and Alkoxyisocaryolanols

Clovane and isocaryolane derivatives have been proven to show several levels of activity against the phytopathogenic fungus Botrytis cinerea. Both classes of sesquiterpenes are reminiscent of biosynthetic intermediates of botrydial, a virulence factor of B. cinerea. Further development of both classes of antifungal agent requires exploration of the structure-activity relationships for the antifungal effects on B. cinerea and phytotoxic effects on a model crop. In this paper, we report on the preparation of a series of alkoxy-clovane and -isocaryolane derivatives, some of them described here for the first time (2b, 2d, 2f-2h, and 4c-4e); the evaluation of their antifungal properties against B. cinerea, and their phytotoxic activites on the germination of seeds and the growth of radicles and shoots of Lactuca sativa (lettuce). Both classes of compound show a correlation of antifungal activity with the nature of side chains, with the best activity against B. cinerea for 2d, 2h, 4c and 4d. In general terms, while 2-alkoxyclovan-9-ols (2a-2e) exert a general phytotoxic effect, this is not the case for 2-arylalkoxyclovan-9-ols (2f-2i) and 8-alkoxyisocaryolan-9-ols (4a-4d), where stimulating effects would make them suitable candidates for application to plants.This research was supported by a grant from Ministerio de Ciencia, Innovacion y Universidades (RTI2018-097356-B-C21, MCIU/AEI/FEDER, EU). A.d.A.P.B., G.G.d.S. and J.A.T. thank Coordenacao de Aperfeicoamento de Pessoal de nivel superior (CAPES, Brazil) for research fellowships (CAPES-DGU 197/09)