Role of amyloid B oligomers in oligodendrocyte and myelin pathology in Alzheimers's disease

145 p.La enfermedad de Alzheimer (EA) es un desorden neurodegenerativo caracterizado por la presencia de placas seniles compuestas por agregados del péptido beta amiloide (Aß), siendo las formas solubles las que mejor correlacionan con la progresión de la enfermedad. Aunque ha sido considerada una patología principalmente asociada a la muerte de las neuronas, se ha descrito un deterioro de sustancia blanca incluso previo al daño neuronal. Por tanto, proponemos que el Aß modula directamente la proliferación y la diferenciación de los oligodendrocitos (OLGs), alterando el estado de la mielina y contribuyendo así al deterioro de la sustancia blanca. En esta tesis, hemos observado que Aß modula la diferenciación de los OLGs, promoviendo la síntesis de la proteína básica de la mielina (MBP) a través de la inducción de la traducción local. Esta modulación está mediada por el receptor integrina ß1, Fyn y CaMKII. Además, el análisis detallado sobre el estado de los OLGs y la mielina en el modelo animal de EA triple transgénico reveló un aumento en la síntesis de MBP así como una desregulación en el patrón de diferenciación de los OLGs. Además, tras realizar estudio de la ultraestructura de la mielina observamos que el animal transgénico mostraba un daño en la integridad de la misma que conllevo fallos en la neurotransmisión. Finalmente, paciente con Alzheimer en fases avanzadas también mostraron un aumento de MBP en la corteza prefrontal y en el hipocampo. Asimismo, elevados niveles tanto de MBP como de CNPase se detectaron en pacientes con problemas cognitivos leves. Estos resultados describen el papel del Aß sobre la función oligodendroglial como parte clave en la progresión de la enfermedad.Achucarro: Basque Center for Neuroscience Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED

30cm of spatial resolution using pre-excitation pulse BOTDA technique

A pre-excitation pulse technique in Brillouin optical time domain analysis (PP-BOTDA) for enhancement of the spatial resolution is shown. The technique here exposed is based on the pre-excitation of the stimulated Brillouin scattering and the subtraction of the Brillouin scattering due to the intensity dc level present in the optical pulse. A main optical pulse with 3ns of duration followed by a pulse of 40ns and half the intensity of the main one are used for obtaining 30cm of spatial resolution. The spatial range is 3600m on a standard single mode optical fiber

Microemulsions as Nanoreactors to Obtain Bimetallic Nanoparticles

Microemulsions are frequently used as nanoreactors for the synthesis of bimetallic nanoparticles. The ability to manipulate the metal distribution in bimetallic nanoparticles is essential for optimizing applications, and it requires a deeper understanding of how compartmentalization of reaction medium affects nanoparticle synthesis. A simulation model was developed to predict the atomic structure of bimetallic nanoparticles prepared via microemulsion in terms of metals employed and microemulsion composition. The model was successfully proved by comparing theoretical and experimental Au/Pt STEM profiles. On this basis, the model becomes a strong tool to further enhance our knowledge of the complex mechanisms governing reactions in microemulsions and its impact on final nanostructures. The purpose of this study is to perform a comprehensive kinetic analysis of coreduction of different couple of metals in the light of the interplay between three kinetic parameters: intermicellar exchange rate, chemical reduction rates of the two metals, and reactants concentration. The particular combination of these factors determines the reaction rate of each metal, which in turn determines the final metal arrangement

Spectral evolution of long-period fiber grating during written process and their influence in the sensitivity

The peak loss wavelength shift, attenuation and bandwidth values on a LPG during the UV multi-pass writing process can be used to estimate the LPG sensitivities in real-time during the fabrication task

Insight into the surface composition of bimetallic nanocatalysts obtained from microemulsions

The enhancement of catalysts efficiency of bimetallic nanoparticles depends on the ability to exert control over surface composition. However, results relating surface composition and feeding solution of bimetallic nanoparticles synthesized in microemulsions are controversial and apparently contradictory. In order to comprehend how the resulting surface can be modified under different synthesis conditions and for different pairs of metals, a computer simulation study was carried out. The resulting surface compositions are explained based on the relative rates of deposition of the two metals, which depend on the particular metal pair, the concentration of reactants and the microemulsion composition. This study provides a satisfactory understanding of experimental results and allows us to identify the main factors affecting the nanoparticle’s surface composition. Consequently, concrete and practical guidelines can be established to facilitate the experimental synthesis of bimetallic nanoparticles with tailored surfacesThis work was supported by Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia, Spain (Grupos Ref. Comp. ED431C 2017/22; and AEMAT ED431E2018/08), “la Caixa” Foundation-Ref: LCF/PR/PR12/11070003”)S

Quasi-distributed liquid level measurement with adaptable optical fiber transducers

A level and flexible quasi-distributed liquid sensor based on the changes in the light transmittance in a plastic optical fiber cable is proposed. The measurement points are constituted by small areas created by side-polishing on a curved fiber and the removal of a portion of the core. These points are distributed and adapted on each full-turn of a spire of fiber built on a cylindrical tube vertically positioned in a tank. The changes between the refractive indexes of air and liquid generate a signal power proportional to the position and level of the liquid. The sensor system was successfully demonstrated in the laboratory and experimental results of three prototypes with 10, 8, and 5 measurement points and with bend radius of 5mm are presented in this paper

Comparative experimental study of a high-temperature raman-based distributed optical fiber sensor with different special fibers

An experimental study of a high temperature distributed optical fiber sensor based on Raman Optical-Time-Domain-Reflectometry (ROTDR) (up to 450 °C) and optical fibers with different coatings (polyimide/carbon, copper, aluminum and gold) is presented. Analysis of the distributed temperature sensor (DTS) measurements determined the most appropriate optical fiber to be used in high temperature industrial environment over long periods of time. To demonstrate the feasibility of this DTS for an industrial application, an optical cable was designed with the appropriate optical fiber and it was hermetically sealed to provide the required mechanical resistance and isolate the fiber from environmental degradations. This cable was used to measure temperature up to 360 °C of an industrial furnace during 7 days.This work has been supported by the Spanish Government through the Ministry of Economy and Competitiveness project TEC2016-76021-C2-2-R, AEI/FEDER (UE) and ENSA through the FACON project

Long integral temperature Brillouin sensor for off- shore wind energy power supply lines

A hybrid Erbium-Brillouin fiber laser sensor to measure the temperature along 22 km fiber is proposed and experimentally demonstrated. A multi-line laser oscillation is induced by the Brillouin gain of different concatenated transducer fiber sections placed in the ring cavity. Integral temperature measurements of each fiber section are obtained through each laser line. This sensor can be used to monitor the temperature of off-shore wind energy power cables