Isoform Specific Reductions in Na + ,K + -ATPase Catalytic (Α) Subunits in the Nerve of Rats with Streptozotocin-Induced Diabetes

Na + ,K + -ATPase activity in nerve is reduced in rats with streptozotocin-induced diabetes; three different isoforms of the Α (catalytic) subunit of the enzyme are present in nerve. Using western blot to determine subunit isoform polypeptide levels in sciatic nerve, we found a substantial reduction in Α1-isoform polypeptide (88% at 3 weeks, 94% at 8 weeks) after induction of diabetes by streptozotocin. Reductions in Α2 and Α3 polypeptide were smaller and not statistically significant. The reduction in amount of all three isoform polypeptides in the nerve of 3-week diabetic animals was corrected by administration of insulin. Accumulation of Α1 polypeptide at a nerve ligature indicated that rapid transport of that polypeptide in nerve occurs with normal kinetics. The results implicate a specific marked deficit in Α1, much more than Α2 or Α3, catalytic subunit isoform of Na + ,K + -ATPase in the pathogenesis of diabetic neuropathy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66384/1/j.1471-4159.1994.63051782.x.pd

Changes in intra-axonal calcium distribution following nerve crush

We used the oxalate-pyroantimonate method to demonstrate the ultrastructural distribution of calcium within rat sciatic nerve 4 h after a crush injury. In normal nerve there are discrete gradients of axoplasmic calcium precipitate with the amount of precipitate decreasing in the axoplasm beneath the Schmidt Lantermann clefts and in the paranodal regions at the node of Ranvier. Near the crush site a marked increase in endoneurial and intra-axonal calcium precipitate correlated with morphologic evidence of axonal degeneration. More distant from the crush site, both in the distal segment destined to degenerate and in the proximal segment destined to regenerate, the most prominent finding was a loss of the normal gradient of precipitate beneath the Schmidt Lantermann clefts. The calcium influx at the crush site corresponds to the known role of calcium in triggering degeneration. The alterations in the distal axon may be an early stage leading to degeneration. Alteration in calcium distribution in the proximal nerve stump may play a role in the regulation of the response to injury.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50077/1/480170508_ftp.pd

Comportamiento mecánico de materiales celulares de carburo de silicio

Los materiales cerámicos celulares tienen un gran número de aplicaciones tecnológicas potenciales y pueden ser decisivos en multitud de procesos industriales a alta temperatura. Esto ha provocado que en los últimos años se hayan iniciado investigaciones sobre las propiedades mecánicas de dichos materiales: la alúmina, la cordierita, el SiC… La información disponible hasta el momento es muy limitada ya que los estudios se han centrado sobre todo en su comportamiento mecánico a temperatura ambiente. Esta tesis analiza detalladamente la relación entre las propiedades mecánicas del SiC celular (módulo de elasticidad, resistencia a compresión, resistencia a flexión y tenacidad de fractura) y su microestructura. Asimismo, también se analiza la evolución de su comportamiento mecánico con la temperatura (entre 25 y 1400 °C). Los dos tipos de SiC celular que se eligieron para la investigación son las espumas Duocel de SiC y el SiC biomórfico. El análisis del comportamiento mecánico realizado sobre el SiC Duocel, fabricado mediante pirólisis de espumas de poliuretano reticuladas y posterior recubrimiento con SiC mediante la técnica de CVD (Chemical Vapour Deposition), mostró que las propiedades no se degradan ni aparecen efectos de corrosión bajo tensión ni de fluencia a1200 °C. La investigación llevada a cabo sobre las espumas de SiC mostró que el principal factor que afecta a su comportamiento mecánico a temperatura ambiente es la densidad real del SiC Duocel, modulada por un factor microestructural de tipo geométrico: la esbeltez de las barras que componen la microestructura. A alta temperatura (a partir de los 1400 °C), la aparición de fenómenos de oxidación y corrosión bajo tensión dio lugar a una rápida degradación de sus propiedades mecánicas. Por último, se estudió el comportamiento mecánico de SiC biomórfico, fabricado mediante pirólisis de dos tipos de madera (eucalipto y haya) y posterior infiltración de la preforma de carbono obtenida con silicio líquido a 1550 °C en vacío. Esta investigación mostró que el principal factor que controla el comportamiento mecánico a temperatura ambiente es la densidad (o porosidad); mientras que la presencia de carbono residual controla las propiedades mecánicas a alta temperatura. Los materiales sin carbono residual mantienen el valor de la resistencia a flexión y a compresión sin degradarse hasta los 1350 °C, mientras que aquéllos que contienen carbono residual en su microestructura después de su procesado mostraron una reducción dramática de estas dos propiedades mecánicas con la temperatura. Cellular ceramic materials have a large number of potential technological applications and can be decisive in many industrial high temperature processes. This has caused that, in the last years, researches about mechanical properties of these materials (alumina, cordierite, silicon carbide…) have been begun. Information available until this moment is very limited, because studies have been centred above all on their mechanical behaviour at ambient temperature. This thesis analyzes in detail the relationship between the mechanical properties of cellular SiC (elastic modulus, compression strength, flexure strength and fracture toughness) and its microstructure. Likewise, the evolution of its mechanical behaviour with temperature (between 25 and 1400 °C) is also analysed. The two kinds of cellular SiC that were selected for this investigation were Duocel SiC foams and biomorphic SiC. The analysis of mechanical behaviour done on Duocel SiC, processed by pirolysis of polyurethane reticulated foams and coating with SiC with the CVD technique (Chemical Vapour Deposition), showed that neither properties are degraded nor corrosion or creep effects appear at 1200 °C. The investigation carried out on SiC foams determined that main factor that affects their mechanical behaviour at ambient temperature is the real density of Duocel SiC, modulated by other geometrical microstructural factor: the slenderness of the bars that make up the microstructure. At high temperature (from 1400 °C), the appearance of oxidation and corrosion under stress phenomenon caused a rapid degradation of mechanical properties. At last, it was studied the mechanical behaviour of biomorphic SiC, processed by pyrolisis of two kind of woods (eucalyptus and beech) and subsequent infiltration of the carbon preform obtained with liquid silicon at 1550 °C in void. This research showed that the main factor that controls the mechanical behaviour at ambient temperature is the density (or porosity); while the presence of residual carbon controls the mechanical properties at high temperature. Materials without residual carbon keep the flexure and compressive strength value up to 1350 °C without degradation, while those that have residual carbon in their microstructure after their fabrication showed a dramatic reduction of these mechanical properties with temperature

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Universidad de Sevilla. Grado en Comunicación Audiovisua

Media, actors of references and power in Paraguay

Introducción. Con la presente investigación se pretende abordar la dinámica política proyectada en los medios de prensa durante el proceso electoral y político de Paraguay en 2013. Metodología. La base empírica utilizada son referencias de nombres incluidas en las noticias de prensa, que fueron analizadas por medio del análisis de redes sociales. Resultados. Se presentan grafos de nombres de actores donde se observa la dinámica referencial en una campaña política que viene precedida y condicionada por la destitución del anterior presidente de la República Fernando Lugo. Conclusiones. El estudio de referencias nominales permite evidenciar la existencia de una continuidad de los partidos tradicionales en Paraguay como instituciones de valor político y mediático, dejando en un papel secundario a actores que emergieron con la llegada de Fernando Lugo al poderIntroduction. This research study aims to empirically address the political dynamics reflected on Paraguay's print press during the 2013 elections campaign. Method. This empirical study is based on the social network analysis of the name references included in a sample of news articles. Results. The results of the study include several graphical representations of the coverage of political actors during the 2013 elections campaign, which was strongly conditioned by the previous impeachment and removal of former President Fernando Lugo. Conclusions. This study of name references confirms the continuity of the traditional parties in Paraguay as institutions with political and media power, and the secondary and peripheral role of the actors that emerged in the political landscape when Fernando Lugo won the presidency of Paraguay.Fil: Juste de Ancos, R.. Universidad Andina Simón Bolívar; EcuadorFil: Soler, Lorena Marina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ortí Mata, M.. Universidad Complutense de Madrid; Españ

Reduction of voltage gated sodium channel protein in DRG by vector mediated miRNA reduces pain in rats with painful diabetic neuropathy

Abstract Background Painful neuropathy is a common complication of diabetes. Previous studies have identified significant increases in the amount of voltage gated sodium channel isoforms NaV1.7 and NaV1.3 protein in the dorsal root ganglia (DRG) of rats with streptozotocin (STZ)-induced diabetes. We found that gene transfer-mediated release of the inhibitory neurotransmitters enkephalin or gamma amino butyric acid (GABA) from DRG neurons in diabetic animals reduced pain-related behaviors coincident with a reduction in NaV1.7 protein levels in DRG in vivo. To further evaluate the role of NaVα subunit levels in DRG in the pathogenesis of pain in diabetic neuropathy, we constructed a non-replicating herpes simplex virus (HSV)-based vector expressing a microRNA (miRNA) against NaVα subunits. Results Subcutaneous inoculation of the miRNA-expressing HSV vector into the feet of diabetic rats to transduce DRG resulted in a reduction in NaVα subunit levels in DRG neurons, coincident with a reduction in cold allodynia, thermal hyperalgesia and mechanical hyperalgesia. Conclusions These data support the role of increased NaVα protein in DRG in the pathogenesis of pain in diabetic neuropathy, and provide a proof-of-principle demonstration for the development of a novel therapy that could be used to treat intractable pain in patients with diabetic neuropathy.http://deepblue.lib.umich.edu/bitstream/2027.42/112553/1/12990_2011_Article_484.pd

Tumor necrosis factor–Α contributes to below-level neuropathic pain after spinal cord injury

Objective Our objective was to elucidate the mechanisms responsible for below-level pain after partial spinal cord injury (SCI). Methods We used lateral hemisection to model central neuropathic pain and herpes simplex viral (HSV) vector–mediated transfer of the cleaved soluble receptor for tumor necrosis factor–Α (TNF-Α) to evaluate the role of TNF-Α in the pathogenesis of below-level pain. Results We found activation of microglia and increased expression of TNF-Α below the level of the lesion in the lumbar spinal cord after T13 lateral hemisection that correlated with emergence of mechanical allodynia in the hind limbs of rats. Lumbar TNF-Α had an apparent molecular weight of 27kDa, consistent with the full-length transmembrane form of the protein (mTNF-Α). Expression of the p55 TNF soluble receptor (sTNFRs) by HSV-mediated gene transfer resulted in reduced pain behavior and a decreased number of ED1-positive cells, as well as decreased phosphorylation of the p38 MAP kinase (p-p38) and diminished expression of mTNF-Α in the dorsal horn. Interpretation These results suggest that expression of mTNF-Α after injury is related to development of pain, and that reverse signaling through mTNF-Α by sTNFR at that level reduces cellular markers of inflammatory response and pain-related behavior. Ann Neurol 2006;59:843–851Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50655/1/20855_ftp.pd

A Formación Profesional Dual en España

Pese a que existen antecedentes normativos que levaron ao nacemento da formación profesional dual, verdadeiramente a formación profesional dual (FPD de aquí en adiante) créase a partir do Real Decreto 1529/2012, do 8 de novembro, polo que se desenvolve o contrato para a formación e a aprendizaxe e se establecen as bases da formación profesional dual. Neste RD, defínese a FPD como: “o conxunto de accións e iniciativas formativas, mixtas de emprego e formación, que teñen por obxecto a cualifiación profesional dos traballadores nun réxime de alternancia da actividade laboral nunha empresa coa formación recibida no marco do sistema de formación profesional para o emprego e do sistema educativo”. Por outro lado, non debemos esquecernos da Orde ESS/2518/2013, de 26 de decembro, pola que se regulan os aspectos formativos do contrato para a formación e a aprendizaxe, que se encarga de definir con máis detalle aqueles aspectos que teñen que ver coa propia actividade formativa (tempo de dedicación, contidos, requisitos dos centros, autorizacións, avaliación, entre outros moitos aspectos relacionados coa formación

La lateralidad en la infancia. Una propuesta práctica para prevenir dificultades

Es de vital importancia, sobre todo en la etapa de Educación Infantil, que los maestros y maestras conozcan las etapas de desarrollo psicomotor por las que el alumnado va pasando, para ayudarles a progresar en sus conocimientos a partir de sus destrezas y habilidades. En esta propuesta de actuación, se presentan actividades que el profesorado puede incluir en el aula para conocer la dominancia lateral de cada uno de sus alumnos y alumnas. El principal objetivo que presenta esta intervención, es transmitir a todos los maestros y maestras de esta etapa, la importancia que tiene que los niños y niñas desarrollen una correcta lateralidad, ya que de no ser así, pueden desencadenar problemas posteriores como la lateralidad cruzada. Dicha propuesta, está dividida en seis sesiones para ir realizando a lo largo de un curso escolar con alumnos y alumnas del segundo ciclo de Educación Infantil, más concretamente con 3º de EI.<br /