Multimodular Bio-Inspired Organized Structures Guiding Long-Distance Axonal Regeneration

Axonal bundles or axonal tracts have an aligned and unidirectional architecture present in many neural structures with different lengths. When peripheral nerve injury (PNI), spinal cord injury (SCI), traumatic brain injury (TBI), or neurodegenerative disease occur, the intricate architecture undergoes alterations leading to growth inhibition and loss of guidance through large distance. In order to overcome the limitations of long-distance axonal regeneration, here we combine a poly-L-lactide acid (PLA) fiber bundle in the common lumen of a sequence of hyaluronic acid (HA) conduits or modules and pre-cultured Schwann cells (SC) as cells supportive of axon extension. This multimodular preseeded conduit is then used to induce axon growth from a dorsal root ganglion (DRG) explant placed at one of its ends and left for 21 days to follow axon outgrowth. The multimodular conduit proved effective in promoting directed axon growth, and the results may thus be of interest for the regeneration of long tissue defects in the nervous system. Furthermore, the hybrid structure grown within the HA modules consisting in the PLA fibers and the SC can be extracted from the conduit and cultured independently. This “neural cord” proved to be viable outside its scaffold and opens the door to the generation of ex vivo living nerve in vitro for transplantation.This research was funded by the Spanish Government’s State Research Agency (AEI) through projects DPI2015-72863-EXP and RTI2018-095872-B-C22/ERDF. Laura Rodríguez Doblado acknowledges scholarship FPU15/04975 of the Spanish Ministry of Education, Culture, and Sports

Web 2.0 and social networks: a study of scientific publications in Spanish communication journals

La comunicación y la publicidad viven actualmente inmersas en un proceso de cambio y evolución constantes, alimentados por la revolución social, cultural y tecnológica que ha supuesto la web 2.0. El trabajo que se presenta tiene como objetivo conocer las principales líneas de trabajo académico en el ámbito de las redes sociales y la web 2.0 en España, estudiando la proyección y el uso que se da a cada una de las metodologías de investigación científica. Para la realización del análisis se han seleccionado las publicaciones sobre este tema en las principales revistas de comunicación en España.Communication and advertising currently live immersed in a process of change and constant evolution, powered by social, cultural and technological revolution that web 2.0 has brought. This work aims to determine the main lines of academic work in the field of social networks and web 2.0 in Spain, studying the projection and the use given to each of the scientific research methodologies. To carry out the analysis it has been done a selection of publications on this topic in major communication journals of Spain

Axonal extension from dorsal root ganglia on fibrillar and highly aligned poly(lactic acid)-polypyrrole substrates obtained by two different techniques: Electrospun nanofibres and extruded microfibres

[EN] The biological behaviour of Schwann cells (SCs) and dorsal root ganglia (DRG) on fibrillar, highly aligned and electroconductive substrates obtained by two different techniques is studied. Mats formed by nanometer-sized fibres of poly(lactic acid) (PLA) are obtained by the electrospinning technique, while bundles formed by micrometer-sized extruded PLA fibres are obtained by grouping microfibres together. Both types of substrates are coated with the electrically conductive polymer polypyrrole (PPy) and their morphological, physical and electrical characterization is carried out. SCs on micrometer-sized substrates show a higher motility and cell-cell interaction, while a higher cell-material interaction with a lower cell motility is observed for nanometer-sized substrates. This higher motility and cell-cell interaction of SCs on the micrometer-sized substrates entails a higher axonal growth from DRG, since the migration of SCs from the DRG body is accelerated and, therefore, the SCs tapestry needed for the axonal growth is formed earlier on the substrate. A higher length and area of the axons is observed for these micrometer-sized substrates, as well as a higher level of axonal sprouting when compared with the nanometer-sized ones. These substrates offer the possibility of being electrically stimulated in different tissue engineering applications of the nervous system.The authors acknowledge financing from the Spanish Government's State Research Agency (AEI) through projects DPI2015-72863-EXP and RTI2018-095872-B-C22/ERDF. FGR acknowledges scholarship FPU16/01833 of the Spanish Ministry of Universities. We thank the Electron Microscopy Service at the UPV, where the FESEM images were obtainedGisbert-Roca, F.; Más Estellés, J.; Monleón Pradas, M.; Martínez-Ramos, C. (2020). Axonal extension from dorsal root ganglia on fibrillar and highly aligned poly(lactic acid)-polypyrrole substrates obtained by two different techniques: Electrospun nanofibres and extruded microfibres. International Journal of Biological Macromolecules. 163:1959-1969. https://doi.org/10.1016/j.ijbiomac.2020.09.181S19591969163Houschyar, K. S., Momeni, A., Pyles, M. N., Cha, J. Y., Maan, Z. N., Duscher, D., … Schoonhoven, J. van. (2016). The Role of Current Techniques and Concepts in Peripheral Nerve Repair. Plastic Surgery International, 2016, 1-8. doi:10.1155/2016/4175293Daly, W., Yao, L., Zeugolis, D., Windebank, A., & Pandit, A. (2011). A biomaterials approach to peripheral nerve regeneration: bridging the peripheral nerve gap and enhancing functional recovery. 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Electrical Stimulation Increases Axonal Growth from Dorsal Root Ganglia Co-Cultured with Schwann Cells in Highly Aligned PLA-PPy-Au Microfiber Substrates

[EN] Nerve regeneration is a slow process that needs to be guided for distances greater than 5 mm. For this reason, different strategies are being studied to guide axonal growth and accelerate the axonal growth rate. In this study, we employ an electroconductive fibrillar substrate that is able to topographically guide axonal growth while accelerating the axonal growth rate when subjected to an exogenous electric field. Dorsal root ganglia were seeded in co-culture with Schwann cells on a substrate of polylactic acid microfibers coated with the electroconductive polymer polypyrrole, adding gold microfibers to increase its electrical conductivity. The substrate is capable of guiding axonal growth in a highly aligned manner and, when subjected to an electrical stimulation, an improvement in axonal growth is observed. As a result, an increase in the maximum length of the axons of 19.2% and an increase in the area occupied by the axons of 40% were obtained. In addition, an upregulation of the genes related to axon guidance, axogenesis, Schwann cells, proliferation and neurotrophins was observed for the electrically stimulated group. Therefore, our device is a good candidate for nerve regeneration therapies.This research was funded by the Spanish Government's State Research Agency (AEI) through project RTI2018-095872-B-C22/ERDF and by RISEUP project FetOpen in H2020 Program: RISEUP 964562 H2020 FetOpen program.Gisbert Roca, F.; Serrano Requena, S.; Monleón Pradas, M.; Martínez-Ramos, C. (2022). Electrical Stimulation Increases Axonal Growth from Dorsal Root Ganglia Co-Cultured with Schwann Cells in Highly Aligned PLA-PPy-Au Microfiber Substrates. International Journal of Molecular Sciences. 23:1-22. https://doi.org/10.3390/ijms231263621222

Influence of synthesis parameters on hyaluronic acid hydrogels intended as nerve conduits

[EN] Hydrogels have widely been proposed lately as strategies for neural tissue regeneration, but there are still some issues to be solved before their efficient use in tissue engineering of trauma, stroke or the idiopathic degeneration of the nervous system. In a previous work of the authors a novel Schwann-cell structure with the shape of a hollow cylinder was obtained using a three-dimensional conduit based in crosslinked hyaluronic acid as template. This original engineered tissue of tightly joined Schwann cells obtained in a conduit lumen having 400 mu m in diameter is a consequence of specific cell-material interactions. In the present work we analyze the influence of the hydrogel concentration and of the drying process on the physicochemical and biological performance of the resulting tubular scaffolds, and prove that the cylinder-like cell sheath obtains also in scaffolds of a larger inner diameter. The diffusion of glucose and of the protein BSA through the scaffolds is studied and characterized, as well as the enzymatic degradation kinetics of the lyophilized conduits. This can be modulated from a couple of weeks to several months by varying the concentration of hyaluronic acid in the starting solution. These findings allow to improve the performance of hyaluronan intended for neural conduits, and open the way to scaffolds with tunable degradation rate adapted to the site and severity of the injury.The authors acknowledge Spanish Ministerio de Ciencia e Innovacion through projects PRI-PIMNEU-2011-1372 (ERANET-Neuron), MAT2011-28791-C03-02 and -03. I. Ortuno Lizaran acknowledges support by CIBER-BBN starting grant.Ortuño-Lizarán, I.; Vilariño, G.; Martínez-Ramos, C.; Monleón Pradas, M.; Vallés Lluch, A. (2016). Influence of synthesis parameters on hyaluronic acid hydrogels intended as nerve conduits. 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Cannabis Use and Emotional Intelligence in Adolescents during COVID-19 Confinement: A Social Network Analysis Approach

[EN] Confinement by COVID-19 had negative consequences on adolescent mental health, including increased cannabis use. Cannabis is related to variables that influence health and well-being. Emotional Intelligence is associated with adaptive coping styles, peer relationships, and social–emotional competencies. In adolescence, peer selection plays a unique role in the initiation of substance use. However, there are no studies during a confinement stage that analyse the relationships between networks, Emotional Intelligence, and cannabis use. The aim of this paper is to describe and analyse the consumption and friendship networks of an adolescent classroom and their relationship with Emotional Intelligence, cannabis use, and gender during COVID-19 confinement. Participants completed different questionnaires for Emotional Intelligence, cannabis use, and the consumption and friendship network. The sample consisted of 21 students from 10th grade, of which 47.6% were consumers. The friendship network correlates with the consumption network, and significant associations between emotional repair and being a cannabis user. The regression model points to the friendship network as a significant variable in predicting the classroom use network. This study highlights the role of the Social Network Analysis in predicting consumption networks during a COVID-19 confinement stage and serves as a tool for cannabis use prevention interventions in a specific population.S

ctuaciones sobre la autonomía, información y participación de los pacientes con cáncer colorrectal en un Hospital de Día de Oncología Médica

Introducción: La Ley 41/2002, de Autonomía del Paciente, obliga a informar para que el paciente participe activamente en la toma de decisiones respecto al diagnóstico y al tratamiento de la enfermedad. Sin embargo, el cáncer conlleva una información adversa y la toma de decisiones por los pacientes oncológicos es un proceso complejo. Objetivo: Conocer las necesidades de los pacientes con cáncer colorrectal atendidos en el Hospital de Día en los aspectos relacionados con la autonomía, información y la participación. Metodología: El estudio se dividió en 3 fases: medición preintervención; intervención y medición postintervención. Resultados: Entre Nov/2007 y Feb/2008, se incluyeron 119 pacientes. Las mejoras solicitadas fueron una consulta de enfermería (68%), más información por escrito (14%) y otras (18%). Se elaboraron 15 documentos informativos y se creó la consulta de enfermería. Los resultados de la primera (n=80) versus (vs) tercera etapa (n= 39) son: información adecuada (83% vs 87%); cree que su diagnóstico es cáncer (57% vs 59%); a quién quiere el paciente que se informe (paciente y familia 85% vs 77%, solo al paciente 10% vs 20%); opinión sobre el CI (buena/muy buena 80% vs 86%); conoce sus derechos (47% vs 84%); conoce la Ley de Autonomía (1% vs 21%), y conoce las Instrucciones previas (0% vs 10%). Conclusiones: Estas intervenciones han modificado el conocimiento de los derechos de los pacientes, de la Ley de Autonomía y las Instrucciones Previas, pero no se ha incrementado el número de pacientes que reconocen que su enfermedad es un cáncer

Solid Polymer Electrolytes Based on Polylactic Acid Nanofiber Mats Coated with Polypyrrole

This is the peer reviewed version of the following article: Gisbert, F., García-Bernabé, A., Compañ, V., Martínez-Ramos, C., Monleón, M., Solid Polymer Electrolytes Based on Polylactic Acid Nanofiber Mats Coated with Polypyrrole. Macromol. Mater. Eng. 2021, 306, 2000584, which has been published in final form at https://doi.org/10.1002/mame.202000584. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The production of electroconductive nanofiber membranes made from polylactic acid (PLA) coated with polypyrrole (PPy) is investigated, performing a scanning of different reaction parameters and studying their physicochemical and dielectric properties. Depending on PPy content, a transition between conduction mechanisms is observed, with a temperature-dependent relaxation process for samples without PPy, a temperature-independent conduction process for samples with high contents of PPy and a combination of both processes for samples with low contents of PPy. A homogeneous and continuous coating is achieved from 23 wt% PPy, observing a percolation effect around 27 wt% PPy. Higher wt% PPy allow to obtain higher conductivities, but PPy aggregates appear from 34% wt% PPy. The high conductivity values obtained for electrospun membranes both through-plane and in-plane (above 0.05 and 0.20 S cm¿1, respectively, at room temperature) for the highest wt% of PPy, their porous structure with high specific surface area and their thermal stability below 140 °C make them candidates for many potential applications as solid polymer electrolytes in, for example, batteries, supercapacitors, sensors, photosensors, or polymer electrolyte membrane fuel cells (PEMFCs). In addition, the biocompatibility of PLA-PPy membranes expand their potential applications also in the field of tissue engineering and implantable devices.The authors acknowledge financing from the Spanish Government's State Research Agency (AEI) through projects DPI2015-72863-EXP and RTI2018-095872-B-C22/ERDF. FGR acknowledges the scholarship FPU16/01833 of the Spanish Ministry of Universities. 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The impact of nationality on the psychophysiological stress response and academic fulfilment in the final degree dissertation

The aims of this study were: i. to analyze the effect of nationality on the psychophysiological stress response of physiotherapy last year students in their final degree dissertations; and ii. to analyze the relationship between the stress response and academic results according to nationality. We evaluated the autonomic stress response, cortical arousal, distress subjective perception, and objective and subjective academic fulfilment in Spanish, Italian, and French physiotherapy students during their final degree dissertation. Results showed a large anticipatory anxiety response before the dissertation in the three student groups. Only the Spanish group showed an increased tendency in the habituation process, reducing the psychophysiological stress response during the dissertation, while the Italian and French groups maintained a large sympathetic activation until the end of the dissertation. Cortical arousal and subjective perception of distress were similar in the three nationalities. In addition, no correlation between academic fulfilment and autonomic modulation was found. We concluded that there was no nationality effect in the psychophysiological stress response of physiotherapy last year students in their final degree dissertation, all of them showing a large anticipatory anxiety response

Engineered axon tracts within tubular biohybrid scaffolds

Injuries to the nervous system that involve the disruption of axonal pathways are devastating to the individual and require specific tissue engineering strategies. Here we analyse a cells-biomaterials strategy to overcome the obstacles limiting axon regenerationin vivo, based on the combination of a hyaluronic acid (HA) single-channel tubular conduit filled with poly-L-lactide acid (PLA) fibres in its lumen, with pre-cultured Schwann cells (SCs) as cells supportive of axon extension. The HA conduit and PLA fibres sustain the proliferation of SC, which enhance axon growth acting as a feeder layer and growth factor pumps. The parallel unidirectional ensemble formed by PLA fibres and SC tries to recapitulate the directional features of axonal pathways in the nervous system. A dorsal root ganglion (DRG) explant is planted on one of the conduit's ends to follow axon outgrowth from the DRG. After a 21 d co-culture of the DRG + SC-seeded conduit ensemble, we analyse the axonal extension throughout the conduit by scanning, transmission electronic and confocal microscopy, in order to study the features of SC and the grown axons and their association. The separate effects of SC and PLA fibres on the axon growth are also experimentally addressed. The biohybrid thus produced may be considered a synthetic axonal pathway, and the results could be of use in strategies for the regeneration of axonal tracts