7,135 research outputs found
L1CAM binds ErbB receptors through Ig-like domains coupling cell adhesion and neuregulin signalling.
During nervous system development different cell-to-cell communication mechanisms operate in parallel guiding migrating neurons and growing axons to generate complex arrays of neural circuits. How such a system works in coordination is not well understood. Cross-regulatory interactions between different signalling pathways and redundancy between them can increase precision and fidelity of guidance systems. Immunoglobulin superfamily proteins of the NCAM and L1 families couple specific substrate recognition and cell adhesion with the activation of receptor tyrosine kinases. Thus it has been shown that L1CAM-mediated cell adhesion promotes the activation of the EGFR (erbB1) from Drosophila to humans. Here we explore the specificity of the molecular interaction between L1CAM and the erbB receptor family. We show that L1CAM binds physically erbB receptors in both heterologous systems and the mammalian developing brain. Different Ig-like domains located in the extracellular part of L1CAM can support this interaction. Interestingly, binding of L1CAM to erbB enhances its response to neuregulins. During development this may synergize with the activation of erbB receptors through L1CAM homophilic interactions, conferring diffusible neuregulins specificity for cells or axons that interact with the substrate through L1CAM
Amino acid metabolism conflicts with protein diversity
The twenty protein coding amino acids are found in proteomes with different
relative abundances. The most abundant amino acid, leucine, is nearly an order
of magnitude more prevalent than the least abundant amino acid, cysteine. Amino
acid metabolic costs differ similarly, constraining their incorporation into
proteins. On the other hand, sequence diversity is necessary for protein
folding, function and evolution. Here we present a simple model for a
cost-diversity trade-off postulating that natural proteomes minimize amino acid
metabolic flux while maximizing sequence entropy. The model explains the
relative abundances of amino acids across a diverse set of proteomes. We found
that the data is remarkably well explained when the cost function accounts for
amino acid chemical decay. More than one hundred proteomes reach comparable
solutions to the trade-off by different combinations of cost and diversity.
Quantifying the interplay between proteome size and entropy shows that
proteomes can get optimally large and diverse
High strength stainless steel 14301 for prestressed concrete structures protection
High Strength Stainless Steels (HSSS) are being developed with the aim to improve corrosion resistance of prestressed concrete structures in aggressive environments. In the present paper focus is given to mechanical and corrosion performance of a HSSS type 14301. The ability of passivation in alkaline media and the risk of local corrosion (pitting) in presence of chlorides, has been determined. Besides, the response of the stainless steel submitted to mechanical strains similar to those in service is considered with respect to the risk of corrosion, Stress Corrosion Cracking (SCC) and Hydrogen Embrittlement (HE). The cold-drawn HSSS 14301 shows higher tolerance to chloride ion than conventional prestressing steel. The local corrosion becomes significant for chloride contents above 0.75 M. The applied load moves pitting corrosion initiation at lower concentrations of chlorides. The pitting enhances risk for SCC developing, although the steel is more resistance to HE in comparison with conventional presstressing ste
Aprendizaje basado en proyectos: aplicación a la asignatura “Proyecto de Embarcaciones Rápidas y a Vela”
En este artículo se presenta la metodología de aprendizaje aplicada a la asignatura “Proyecto de Embarcaciones Rápidas y a Vela”, optativa del grado de Arquitectura Naval de la UPM. Proponemos un enfoque amplio basado en proyectos (PBL), con tres objetivos: que los alumnos realicen un ante-proyecto de embarcación rápida o a vela; que conecten con la realidad industrial del sector; y, por último, estimular su curiosidad y motivación hacia el contenido del curso. La asignatura se divide en dos bloques temáticos y tres módulos de trabajo, dos teóricos y uno práctico. Para evaluar el cumplimento de los objetivos propuestos se ha realizado una encuesta a los alumnos y se analizan algunos de los proyectos entregados por ellos. El artículo se cierra con conclusiones y propuestas de trabajo futuro
Influencia de la disponibilidad de oxigeno en el mecanismo de formación de la película pasiva de armaduras de acero en medio alcalino.
El carácter El carácter fuertemente fuertemente alcalino alcalino dede lala solución solución acuosa acuosa dede los los poros poros dede hormigón hormigón vava aa provocar provocar lala generación generación dede una capa una capa pasivante pasivante constituida constituida por por óxidos óxidos dede hierro hierro sobre sobre lala superficie superficie dede lala armadura armadura enen contacto contacto con con elel hormigón. hormigón. Esta Esta capa capa dede óxidos óxidos eses termodinámicamente termodinámicamente yy cinéticamente cinéticamente variable variable yy evoluciona evoluciona con con elel tiempo, tiempo, término conocido término conocido comúnmente comúnmente como como “envejecimiento” “envejecimiento”.. La estructura La estructura yy composición composición dede esta esta capa capa pasiva pasiva pueden pueden variar variar enen función función dede parámetros parámetro como el como el pHpH del del medio, medio, elel contenido contenido enen OO , composición , composición dede lala fase fase acuosa, acuosa, lala temperatura, temperatura, etc. etc. yy sufrir sufrir modificaciones modificaciones con con elel tiempo tiempo como como consecuencia consecuencia dede estos estos parámetr
Chromosomal transformation in Bacillus subtilis is a non-polar recombination reaction
Natural chromosomal transformation is one of the primary driving forces of bacterial evolution. This reaction involves the recombination of the internalized linear single-stranded (ss) DNA with the homologous resident duplex via RecA-mediated integration in concert with SsbA and DprA or RecO. We show that sequence divergence prevents Bacillus subtilis chromosomal transformation in a log-linear fashion, but it exerts a minor effect when the divergence is localized at a discrete end. In the nucleotide bound form, RecA shows no apparent preference to initiate recombination at the 3′- or 5′-complementary end of the linear duplex with circular ssDNA, but nucleotide hydrolysis is required when heterology is present at both ends. RecA·dATP initiates pairing of the linear 5′ and 3′ complementary ends, but only initiation at the 5′-end remains stably paired in the absence of SsbA. Our results suggest that during gene transfer RecA·ATP, in concert with SsbA and DprA or RecO, shows a moderate preference for the 3′-end of the duplex. We show that RecA-mediated recombination initiated at the 3′- or 5′-complementary end might have significant implication on the ecological diversification of bacterial species with natural transformation
Journals’ policies of storage and reuse of raw research data and their impact in five scientific areas
Analisys of journals' policies about storage and re-use of raw research data
Spongionella Secondary Metabolites Regulate Store Operated Calcium Entry Modulating Mitochondrial Functioning in SH-SY5Y Neuroblastoma Cells
cknowledgements The research leading to these results has received funding from the following FEDER cofounded-grants. From CDTI and Technological Funds, supported by Ministerio de Economía y Competitividad, AGL2012-40185-CO2-01, AGL2014-58210-R, and Consellería de Cultura, Educación e OrdenaciónUniversitaria, GRC2013-016, and through AxenciaGalega de Innovación, Spain, ITC-20133020 SINTOX. From CDTI under ISIP Programme, Spain, IDI-20130304 APTAFOOD. From the European Union's Seventh Framework Programme managed by REA - Research Executive Agency (FP7/2007-2013) under grant agreement 312184 PHARMASEA. Jon Andoni Sánchez is supported by a fellowship from Plan Galego de Investigación e Crecemento, Xunta de Galicia, Spain.Peer reviewedPublisher PD
Effect of Exercise on Inflammation in Hemodialysis Patients: A Systematic Review
Background: In recent years, physical exercise has been investigated for its potential as a therapeutic tool in patients with end-stage renal disease (ESRD) undergoing hemodialysis maintenance treatment (HD). It has been shown that regular practice of moderate-intensity exercise can improve certain aspects of immune function and exert anti-inflammatory effects, having been associated with low levels of pro-inflammatory cytokines and high levels of anti-inflammatory cytokines. Purpose: The aim of this review is to examine the studies carried out in this population that analyzed the effect of intradialytic exercise on the inflammatory state and evaluate which exercise modality is most effective. Methods: The search was carried out in the MEDLINE, CINAHL Web of Science and Cochrane Central Register of Controlled Trials databases from inception to June 2022. The PEDro scale was used to assess methodological quality, and the Cochrane Risk of Bias Tool and MINORS were used to evaluate the risk of bias. The quality of evidence was assessed with GRADE scale. The outcome measures were systemic inflammation biomarkers. Results: Mixed results were found in terms of improving inflammation biomarkers, such as CRP, IL-6 or TNFα, after exercise. Aerobic exercise seems to improve systemic inflammation when performed at medium intensity while resistance training produced better outcomes when performed at high intensity. However, some studies reported no differences after exercise and these results should be taken with caution. Conclusions: The low quality of the evidence suggests that aerobic and resistance exercise during HD treatment improves systemic inflammation biomarkers in patients with ESRD. In any case, interventions that increase physical activity in patients with ESRD are of vital importance as sedentary behaviors are associated with mortality. More studies are needed to affirm solid conclusions and to make intervention parameters, such as modality, dose, intensity or duration, sufficiently clear
Potenciar la experiencia y habilidades frente a problemas prácticos en las clases de laboratorio de “Flotabilidad y Estabilidad”
En este trabajo se presentan las medidas adoptadas en las prácticas de la asignatura “Flotabilidad y Estabilidad”, del grado de “Arquitectura Naval” de la UPM, para potenciar la capacidad de los alumnos de enfrentarse a problemas prácticos y para entender la casuística que ellos involucran (necesidad de planificación, manejo de herramientas, etc.). En concreto, se describen: a) Una actividad complementaria, introducida en el curso 2019/2020, que involucra la realización de un experimento con un barco real; b) La adaptación de las prácticas a formato no presencial en el curso 2020/2021. Este cambio de formato, consecuencia de la situación de pandemia, tiene en principio un efecto negativo en cuanto al objetivo que se persigue. Para tratar de minimizarlo, se introdujo un nuevo concepto de práctica en la que los alumnos realizaron un experimento casero, devolviendo así el aspecto práctico a la actividad, a pesar de la no presencialidad. En este artículo se evalúa la efectividad de las medidas implementadas en cuanto al cumplimento del objetivo de mejorar la capacidad de los alumnos de enfrentar problemas prácticos, así como de otros objetivos que se buscan con las prácticas. El artículo se cierra con conclusiones y propuestas de trabajo futuro
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