Absence of R-Ras1 and R-Ras2 causes mitochondrial alterations that trigger axonal degeneration in a hypomyelinating disease model

Fast synaptic transmission in vertebrates is critically dependent on myelin for insulation and metabolic support. Myelin is produced by oligodendrocytes (OLs) that maintain multilayered membrane compartments that wrap around axonal fibers. Alterations in myelination can therefore lead to severe pathologies such as multiple sclerosis. Given that hypomyelination disorders have complex etiologies, reproducing clinical symptoms of myelin diseases from a neurological perspective in animal models has been difficult. We recently reported that R-Ras1 and/or R-Ras2 mice, which lack GTPases essential for OL survival and differentiation processes, present different degrees of hypomyelination in the central nervous system with a compounded hypomyelination in double knockout (DKO) mice. Here, we discovered that the loss of R-Ras1 and/or R-Ras2 function is associated with aberrant myelinated axons with increased numbers of mitochondria, and a disrupted mitochondrial respiration that leads to increased reactive oxygen species levels. Consequently, aberrant myelinated axons are thinner with cytoskeletal phosphorylation patterns typical of axonal degeneration processes, characteristic of myelin diseases. Although we observed different levels of hypomyelination in a single mutant mouse, the combined loss of function in DKO mice lead to a compromised axonal integrity, triggering the loss of visual function. Our findings demonstrate that the loss of R-Ras function reproduces several characteristics of hypomyelinating diseases, and we therefore propose that R-Ras1 and R-Ras2 neurological models are valuable approaches for the study of these myelin pathologies.Spanish Ministry of Economy and Competitiveness (RTI2018-096303B-C33) to B. C., (RTI2018-096303B-C31) to F. W., and RTI2018-095166B-I00 to C. G. R. and P. L. and Instituto de Salud Carlos III and co-funded by the European Regional Development Fund (ERDF) within the “Plan Estatal de Investigación Científica y Técnica y de Innovación 2017–2020” (RD16/0008/0020; FIS/PI 18-00754

La complejidad terapéutica tras el implante de una válvula aórtica transcatéter (TAVI): un caso infrecuente de trombosis y endocarditis

La implantación de una válvula aórtica transcatéter (TAVI, transcatheter aortic valve implantation) es una práctica extendida en pacientes con estenosis aórtica de riesgo quirúrgico intermedio y alto. Se han descrito complicaciones como endocarditis e incluso trombosis valvular clínica, aunque con una incidencia de esta última de tan sólo 0.6% a 2.8% y es más frecuente luego los procedimientos valve-in-valve y válvulas expandibles con balón. La trombosis debe sospecharse en cualquier paciente con síntomas recientes de insuficiencia cardíaca, un episodio embólico o aumento manifiesto de los gradientes. La antivitamina K o la heparina no fraccionada son la primera línea de tratamiento. En la actualidad existe controversia acerca del tratamiento y la necesidad de la doble antiagregación tras el implante, ya que ésta parece aumentar los episodios hemorrágicos sin reducir las complicaciones isquémicas..

En red-damos: Tejiendo experiencias de transformación educativa

28 páginasEste libro nace de las experiencias de docentes de diferentes niveles educativos, quienes realizan aportes a la comprensión y aplicación de diversos medios didácticos para el favorecimiento del aprendizaje en sus estudiantes. En este contexto, se busca que los principales lectores sean colegas docentes de latitudes y contextos variados, pero con similar entusiasmo por intervenir en su ejercicio pedagógico.Primera edició

The \u3cem\u3eChlamydomonas\u3c/em\u3e Genome Reveals the Evolution of Key Animal and Plant Functions

Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella

Successful wide hybridization and introgression breeding in a diverse set of common peppers (Capsicum annuum) using different cultivated ají (C. baccatum) accessions as donor parents

[EN] Capsicum baccatum, commonly known as aji, has been reported as a source of variation for many different traits to improve common pepper (C. annuum), one of the most important vegetables in the world. However, strong interspecific hybridization barriers exist between them. A comparative study of two wide hybridization approaches for introgressing C. baccatum genes into C. annuum was performed: i) genetic bridge (GB) using C. chinense and C. frutescens as bridge species; and, ii) direct cross between C. annuum and C. baccatum combined with in vitro embryo rescue (ER). A diverse and representative collection of 18 accessions from four cultivated species of Capsicum was used, including C. annuum (12), C. baccatum (3), C. chinense (2), and C. frutescens (1). More than 5000 crosses were made and over 1000 embryos were rescued in the present study. C. chinense performed as a good bridge species between C. annuum and C. baccatum, with the best results being obtained with the cross combination [C. baccatum (female) x C. chinense (male)] (female) x C. annuum (male), while C. frutescens gave poor results as bridge species due to strong prezygotic and postzygotic barriers. Virus-like-syndrome or dwarfism was observed in F-1 hybrids when both C. chinense and C. frutescens were used as female parents. Regarding the ER strategy, the best response was found in C. annuum (female) x C. baccatum (male) crosses. First backcrosses to C. annuum (BC(1)s) were obtained according to the crossing scheme [C. annuum (female) x C. baccatum (male)] (female) x C. annuum (male) using ER. Advantages and disadvantages of each strategy are discussed in relation to their application to breeding programmes. These results provide breeders with useful practical information for the regular utilization of the C. baccatum gene pool in C. annuum breeding.Juan P. Manzur thanks Universitat Politecnica de Valencia for a research predoctoral grant (2011-S2-4264, programa para la formacion de personal investigador). Authors are grateful to Centro Inv. Agr. Mabegondo, S. Larregla from NEIKER, P.W. Bosland from NMSU and the Consejos Reguladores of IGP Pimiento Asado del Bierzo, DOP Pimenton de Murcia, and IGP Piquillo de Lodosa for providing us with seeds from Arnoia, Guindilla de Ibarra, Numex, Bierzo, Bola and Piquillo, respectively.Manzur Poblete, JPA.; Fita, A.; Prohens Tomás, J.; Rodríguez Burruezo, A. (2015). Successful wide hybridization and introgression breeding in a diverse set of common peppers (Capsicum annuum) using different cultivated ají (C. baccatum) accessions as donor parents. PLoS ONE. 10(12). https://doi.org/10.1371/journal.pone.0144142Se0144142101

Evaluatión del Programa Nacioanl de Enseñanza de la Lengua Portuguesa (PNEP) en la educación primaria: las percepitiones de los estudiantes

Este artigo apresenta um estudo das perceções dos alunos sobre o Programa Nacional de Ensino do Português (PNEP), um programa de formação contínua de professores de 1.º ciclo criado com a finalidade de melhorar o processo de ensino e aprendizagem do português naquele ciclo de escolaridade e implementado no contexto da atividade profissional. Os resultados da análise quantitativa de dados, recolhidos através de um inquérito por questionário aplicado aos alunos no final da formação de 20092010 no núcleo regional de formação sedeado na Universidade do Minho, revelam representações muito positivas dos alunos sobre o processo de aprendizagem e sobre os conteúdos de aprendizagem experimentados. Estes dados apontam para a validade da conceção da pedagogia da língua que sustentou o PNEP, ilustram a perceção positiva que os professoresformandos revelaram sobre o seu próprio processo de desenvolvimento profissional e constituem-se como caso ilustrativo da exequibilidade da realização de inquéritos com crianças pequenas.This article presents a study of students' perceptions about the National Program of Portuguese Language Teaching (PNEP), an in-service program for primary school teachers aimed at improving the teaching and the learning of Portuguese language and implemented in the context of professional activity. The results of the quantitative analysis of data, collected through a survey questionnaire administered to students at the end of the 2009-2010 year in the regional center located at the University of Minho, reveal very positive representations about the learning process and about the contents of learning. These data point to the validity of the language pedagogy design that supported PNEP, illustrate the positive perception that teachers revealed on their own professional development and emerge as an illustrative case of the feasibility of conducting surveys with primary-school children.En este artículo se presenta un estudio de las percepciones de los estudiantes sobre el Programa Nacional de Enseñanza de la Lengua Portuguesa (PNEP), un programa de formación continua para profesores de educación primaria creado con el fin de mejorar la enseñanza y el aprendizaje del portugués en el contexto de la actividad profesional. Los resultados del análisis cuantitativo de los datos, recogidos a través de un cuestionario administrado a los estudiantes al final de la formación 2009-2010 en el núcleo regional de formación ubicado en la Universidad de Minho, revelan representaciones muy positivas sobre el proceso y sobre los contenidos del aprendizaje. Estos datos apuntan a la validez de la pedagogía de la lengua que apoyó el PNEP, ilustran la percepción positiva que los profesores revelaron sobre su propio desarrollo profesional y se presentan como caso ilustrativo de la viabilidad de la realización de encuestas con los niños pequeños.Este texto foi realizado no âmbito de uma licença sabática da primeira autora, subvencionada pela FCT (SFRH/BSAB/1440/2014).info:eu-repo/semantics/publishedVersio

Language attitudes towards Spanish and Catalan in autochthonous and immigrant families in Catalonia: analysing the correlation between student attitudes and their parents’¿

This paper analyses the language attitudes of autochthonous and immigrant families living in Catalonia towards Spanish and Catalan. The research is intended to assess the possible differences in the language attitudes of students and their parents towards the two languages spoken in Catalonia. The investigation takes a sample of 476 students and their families from several cities in Catalonia who answered an attitude questionnaire. The data were analysed with SPSS and t-tests were performed, with students reporting better attitudes towards Catalan and parents showing more favourable views on Spanish. Statistically significant differences were identified between local and immigrant participants, with non-Spanish families showing worse attitudes to Catalan than towards Spanish. A correlation was found between autochthonous students and their parents when it comes to language attitudes towards the two languages, suggesting that the family environment does have an impact on the development of language attitudes. However, this effect is less visible in the case of immigrant families, where social and educational elements could moderate the impact of language attitudes within the family.This work was supported by the Ministry of Economy and Competitiveness of Spain by the Grants EDU2014-54093-R, EDU2017-82479-R and IJCI-2016-28250; the Catalan Government’s Agency for Management of University and Research Grants (AGAUR) by the Grant 2017 SGR 32