332 research outputs found

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

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    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

    460 Progress Towards A Phase 1/2 Trial Of Hsv‐Mediated Gene Transfer Of Gad In Patients With Painful Diabetic Neuropathy

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90202/1/S1754-3207_10_70465-X.pd

    Changes in intra-axonal calcium distribution following nerve crush

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    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

    Exploring the treatment of epilepsy through intrahippocampal GABA modulation with an HSVvector expressing GAD67

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    Articlehttp://deepblue.lib.umich.edu/bitstream/2027.42/96990/1/UMURF-Issue06_2009-MMooney.pd

    Teaching guidelines for creative writing workshop proposal to upper primary

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    La millora de l’expressió escrita dels alumnes sempre ha estat una de les grans preocupacions i tot un repte pels mestres de primària. La present investigació pretén estudiar la situació actual a fi de millorar la qualitat de l’acció educativa partint de la pregunta de si l’escriptura creativa ajuda a millorar l’expressió escrita. L’estudi s’ha dividit en tres grans apartats: el marc teòric elaborat gràcies a la recerca i l’aportació de grans escriptors i experts en l’àmbit; el disseny, la planificació i l’aplicació d’un taller d’escriptura creativa a cinquè i l’elaboració d’unes orientacions didàctiques destinades als docents.The improvement of the students’ writing skill has always been one of the most important concerns and a great challenge for teachers at Primary Education. The following investigation studies the current situation in order to improve the quality of the educational action with the question "Does creative writing help to improve writing expression?”. This research has been divided in three main parts: the theory taken from the literature done by specialist in the topic, the design, planning and application of a creative writing workshop in fifth and sixth grade and the elaboration of educational orientations for teachers

    Comportamiento mecánico de materiales celulares de carburo de silicio

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    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

    Todo va sobre ruedas

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    Universidad de Sevilla. Grado en Comunicación Audiovisua

    Para el planeta cuidar, no debemos contaminar. Una propuesta destinada para Educación Primaria

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    Uno de los temas más recurrentes en la sociedad actual tiene relación con el cuidado del medioambiente, ya que es necesario que la población comience a tomar conciencia sobre los graves problemas que se generan debido al estilo de vida del ser humano. En este trabajo se defiende el uso de la educación ambiental con el objetivo de desarrollar una conciencia ambiental en los niños y niñas de Educación Primaria, para que en un futuro se conviertan en ciudadanos que respetan y cuidan el medio natural. Utilizando la metodología de Aprendizaje Basado en Proyectos se expone una propuesta de intervención para un aula de tercero de primaria en la que trabajar todos estos aspectos.One of the most recurrent themes in today's society is related to the care of the environment, as it is necessary for the population to begin to become aware of the serious problems that are generated due to the lifestyle of the human being. This final degree project defends the use of Environmental Education with the aim of developing an Environmental Conscience in primary school children, so that in the future they will become citizens who respect and take care for the natural environment. Using the Project-Based Learning methodology, an intervention proposal is presented for a third-year primary classroom in which all these aspects are worked on.Grado en Educación Primari

    HSV-mediated expression of interleukin-4 in dorsal root ganglion neurons reduces neuropathic pain

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    BACKGROUND: To examine the role of inflammatory mediators in neuropathic pain, we used a replication-defective genomic herpes simplex virus (HSV)-based vector containing the coding sequence for the anti-inflammatory peptide interleukin (IL)-4 under the transcriptional control of the HSV ICP4 immediate early promoter, vector S4IL4, to express IL-4 in dorsal root ganglion (DRG) neurons in vivo. RESULTS: Subcutaneous inoculation of S4IL4 in the foot transduced lumbar DRG to produce IL-4. Transgene-mediated expression of IL-4 did not alter thermal latency or tactile threshold in normal animals, but inoculation of S4IL4 1 week after spinal nerve ligation (SNL) reduced mechanical allodynia and reversed thermal hyperalgesia resulting from SNL. Inoculation of S4IL4 1 week before SNL delayed the development of thermal hyperalgesia and tactile allodynia, but did not prevent the ultimate development of these manifestations of neuropathic pain. S4IL4 inoculation suppressed non-noxious-induced expression of c-Fos immunoreactivity in dorsal horn of spinal cord and reversed the upregulation of spinal IL-1β, PGE2, and phosphorylated-p38 MAP kinase, characteristic of neuropathic pain. CONCLUSION: HSV-mediated expression of IL-4 effectively reduces the behavioral manifestations of neuropathic pain, and reverses some of the biochemical and histologic correlates of neuropathic pain at the spinal level
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