Anti-oxidant and anti-inflammatory activity of ketogenic diet. New perspectives for neuroprotection in alzheimer’s disease

The ketogenic diet, originally developed for the treatment of epilepsy in non-responder children, is spreading to be used in the treatment of many diseases, including Alzheimer’s disease. The main activity of the ketogenic diet has been related to improved mitochondrial function and decreased oxidative stress. B-Hydroxybutyrate, the most studied ketone body, has been shown to reduce the production of reactive oxygen species (ROS), improving mitochondrial respiration: it stimulates the cellular endogenous antioxidant system with the activation of nuclear factor erythroid-derived 2-related factor 2 (Nrf2), it modulates the ratio between the oxidized and reduced forms of nicotinamide adenine dinucleotide (NAD+/NADH) and it increases the efficiency of electron transport chain through the expression of uncoupling proteins. Furthermore, the ketogenic diet performs anti-inflammatory activity by inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) activation and nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome as well as inhibiting histone deacetylases (HDACs), improving memory encoding. The underlying mechanisms and the perspectives for the treatment of Alzheimer’s disease are discussed

Is There a Calcification Factor Common to All Calcifying Matrices?

This paper reviews the principal morphological findings pertinent to the early phases of the calcification process and explores the possibility that there may be a calcification factor common to all calcifying matrices. Three structures have a main role in calcification: collagen fibrils, matrix vesicles, and crystal ghosts. Only crystal ghosts are present in all calcified tissues, so that only they can be taken into consideration as a common calcification factor. They are organic molecules which have the same morphology as that of the inorganic structures present in the calcified matrix, which means that they can be considered as templates for those structures. Early calcification might be initiated by the binding of calcium and phosphate ions to the unmasked reactive groups of the crystal ghosts which are probably contained not only in the matrix, but also in the holes of the collagen fibrils and in matrix vesicles. The available data suggest that crystal ghosts share many of the properties of crystal bound proteins . The involvement of alkaline phosphatase in their composition may account for their calcium-and phosphate-binding activity

Characterization of the Stellar / Substellar Boundary

The aim of this dissertation is to address the topic of distinguishing very low mass stars from brown dwarfs through observational means. To that end, we seek to better characterize both populations and establish mechanisms that facilitate establishing an individual object\u27s membership in either the very low mass star or the brown dwarf populations. The dissertation is composed of three separate observational studies. In the first study we report on our analysis of HST/NICMOS snapshot high resolution images of 255 stars in 201 systems within ~10 parsecs of the Sun. We establish magnitude and separation limits for which companions can be ruled out for each star in the sample, and then perform a comprehensive sensitivity and completeness analysis for the subsample of 138 M dwarfs in 126 systems. We calculate a multiplicity fraction of $0.0-0.0+3.5$2.3-0.7+5.0% for L and T companions to M dwarfs in the separation range of 10 to 70 AU. Considering these results and results from several other studies, we argue that the so-called brown dwarf desert extends to binary systems with low mass primaries and is largely independent of primary mass, mass ratio, and separation. In the second study we construct a Hertzsprung-Russell diagram for the stellar/substellar boundary based on a sample of 63 objects ranging in spectral type from M6V to L4. We report new VRI photometry for 63 objects and new trigonometric parallaxes for 37 objects. We employ a novel SED fitting algorithm to determine effective temperatures, bolometric luminosities, and radii. We find evidence for the local minimum in the radius-temperature and radius-luminosity trends that may indicate the end of the stellar main sequence and the start of the brown dwarf sequence at $Teff ~2075K, log(L/Lsun) ~ -3.9, and (R/Rsun) ~ 0.086. The third study is a pilot study for future work and part of a long term search for astrometric binaries that have the potential to yield dynamical masses. We report the discovery of five new multiple systems and discuss their potential for determining dynamical masses: LHS 2071AB, GJ 1215 ABC, LTT 7434 AB, LHS 501 AC, and LHS 3738 AB

Measurement techniques in a transonic wind tunnel. Total temperature and turbulence characterization.

A new refrigeration solution for high by-pass ratio engines is the main objective of the Intelligent Cooling System project. This study is based on a surface integrated air-oil heat exchanger placed at the location of the air separator nose within the bypass flow of a turbofan. The aim is to help the cooling of the oil circuit without disturbing the air stream and decreasing the overall efficiency of the engine. The present work focuses on the aerodynamic characterization of the interaction between the three dimensional bypass flow and different configurations of finned heat exchangers. This research is done in von Karman Institute in a new blowdown wind tunnel characterized by an helicoidal test section specifically design within this project in order to reproduce the engine bypass flow in the region of interest. This report presents the work performed for the calibration and implementation of the thermocouples and hot wire anemometers used for total temperature and turbulence measurements, as well as part of the flow results, with the relative postprocessing methodology. Finally the uncertainties analysis was done in order to estimate the goodness of the results and to identify the major sources of errors

El orgullo del primer número de la revista Science of Human Action

Para una Institución de Educación Superior es vital la consolidación del proceso investigativo, pues es éste el motor que retroalimenta y dinamiza a la docencia y la extensión universitaria. No puede concebirse a la universidad sin la investigación. Ahora bien, la investigación debe ser sometida a la evaluación de expertos y debe estar disponible para la comunidad en general, con la finalidad no sólo de cumplir un requisito académico, sino de compartir y hacer extensivo el conocimiento generado por medio de la investigación. Por eso el nacimiento de una revista científica debe celebrarse, ya que es otra forma de extender la universida

Avaliação toxicológica da exposição de tainhas Mugil platanus à fração solúvel do petróleo em água

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Aqüicultura, Instituto de Oceanografia, 2010.O desenvolvimento humano tem contribuído com o aumento dos níveis de poluentes nos ambientes aquáticos. Dentre os principais poluentes encontrados nos corpos hídricos, destacam-se os hidrocarbonetos do petróleo. Frente aos problemas de degradação dos ecossistemas aquáticos, novas espécies vêm sendo testadas como possíveis indicadoras da integridade ambiental. O presente estudo determinou a concentração letal mediana (CL50) para espécie Mugil platanus frente a exposição aguda à fração solúvel do petróleo em água (FSA). Estudos histopatológicos e a análise da frequência de micronúcleos foram também observados em teste crônico. Juvenis de tainha (25 ± 2,3 g) foram expostos a três concentrações crônicas (1,7, 3,5 e 7%), mais o grupo controle por 14 dias com mais 7 dias de período de depuração (sem FSA). Ao longo do período experimental (24, 96 h, 14 e 21 dias) foram coletadas amostras sanguíneas da veia caudal para observação de micronúcleos (MC) e amostras de fígado e brânquias para visualização de histopatologias. Para esses procedimentos foram amostrados sete peixes por concentração testada. A CL50 para 96 h foi estimada em 37,5% da FSA e o nível de segurança em 3,5% da FSA. O tempo requerido para formação de MC foi de 96 h de exposição. O tempo de depuração foi suficiente para que fosse atingida a frequência de eritrócitos similar ao do grupo controle. Estudos histopatológicos indicaram mudanças severas nas brânquias e no tecido hepático. A telangiectasia foi a histopatologias branquial mais relevante. Histopatologias hepáticas como colestase, dilatação dos sinusóides e infiltrados inflamatórios foram comumente observadas. O teste do micronúcleo e o estudo histológico detectaram com eficácia alguns danos gerados pela exposição crônica de juvenis de tainha à FSA.Human development has contributed to increased levels of pollutants in aquatic environments. Among the main pollutants found in water bodies, the petroleum hydrocarbons have a prominent place. Facing the problems of degradation of aquatic ecosystems, new species are being tested as possible indicators of environmental integrity. This study determined the median lethal concentration (LC50) for mullet Mugil platanus facing acute exposure to the soluble fraction of oil in water (FSA). Histopathological studies and micronuclei frequency analysis were also studied in chronic tests. Mullet juveniles (25 ± 2.3 g) were exposed to three chronic concentrations (1.7, 3.5 and 7%), plus the control group for 14 days over 7 days without FSA. Throughout the experimental period (24, 96 h, 14 and 21 days) blood samples were collected from the caudal vein for observation of micronuclei (MC) and samples of liver and gills for histopathological study. For these procedures seven fish were sampled per concentration tested. The LC50 for 96 h was estimated at 37.5% of FSA and the safe level at 3.5% of FSA. The time required for the formation of MC was 96 h of exposure. The time of clearance was sufficient to achieve a similar MC frequency of the control group. Histopathological studies showed severe changes in the gill and liver tissues. The most relevant histopathology in the gills was telangiectasia. Hepatic histopathology as cholestasis, dilated sinusoids and inflammatory infiltrates were commonly described. The MC test and histological study effectively detected some damage caused by exposure of juvenile mullet to the FSA

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