998 resultados para GONZÁLEZ PÉREZ, JORGE
Resumo:
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. Most morbidity associated with the metabolic syndrome is related to vascular complications, in which endothelial dysfunction is a major pathogenic factor. However, whether NAFLD is associated with endothelial dysfunction within the hepatic vasculature is unknown. The aims of this study were to explore, in a model of diet-induced overweight that expresses most features of the metabolic syndrome, whether early NAFLD is associated with liver endothelial dysfunction. Wistar Kyoto rats were fed a cafeteria diet (CafD; 65% of fat, mostly saturated) or a control diet (CD) for 1 month. CafD rats developed features of the metabolic syndrome (overweight, arterial hypertension, hypertryglyceridemia, hyperglucemia and insulin resistance) and liver steatosis without inflammation or fibrosis. CafD rats had a significantly higher in vivo hepatic vascular resistance than CD. In liver perfusion livers from CafD rats had an increased portal perfusion pressure and decreased endothelium-dependent vasodilation. This was associated with a decreased Akt-dependent eNOS phosphorylation and NOS activity. In summary, we demonstrate in a rat model of the metabolic syndrome that shows features of NAFLD, that liver endothelial dysfunction occurs before the development of fibrosis or inflammation.
Resumo:
En este trabajo examinamos si la teoría de expectativas con primas de liquidez constantes puede explicar la estructura temporal de los tipos de interés de pequeños vencimientos en el mercado interbancario de depósitos español, para datos mensuales desde 1977 hasta 1995. Utilizamos el contraste de Campbell y Shiller (1987) basado en un modelo VAR cointegrado. A partir de las estimaciones consistentes de dicho modelo obtenemos la magnitud y persistencia de los shocks a través de la simulación de la respuesta al impulso, y estimaciones eficientes de los parámetros modelizando la varianza condicional que es variable en el tiempo. En este sentido, se proponen varios esquemas de volatilidad que permiten plantear distintas aproximaciones de laincertidumbre en un entorno multiecuacional GARCH y que están basadas en el modelo de expectativas propuesto. La evidencia empírica muestra que se incumple la teoría de las expectativas, que existe una dinámica conjunta a corto plazo para los tipos de interés y el diferencial que está definida por un modelo VAR(4)-GARCH( 1,1)-BEKK (que está próximo a la integrabilidad en varianza), y que existen distintos factores de riesgo que afectan a las primas en los plazos estudiados
Resumo:
This paper deals with the product design, engineering, and material selection intended for the manufacturing of an eco-friendly chair. The final product is expected to combine design attributes with technical and legal feasibility with the implementation of new bio-based materials. Considering the industrial design, a range of objectives and trends were determined after setting the market requirements, and the final concept was proposed and modeled. The product geometry, production technology, and legal specifications were the input data for product engineering. The material selection was based on the technical requirements. Polypropylene (PP) composite materials based on coupled-fiberglass, sized-fiberglass, and coupled-stone ground wood reinforcements were prepared and characterized. Final formulations based on these PP composites are proposed and justified
Resumo:
El Reglamento 1223/2009 establece las normas que deben cumplir todos los productos cosméticos comercializados en Europa, con objeto de velar por el funcionamiento del mercado interior y lograr un elevado nivel de protección de la salud humana garantizando el uso de métodos alternativos que no impliquen la utilización de animales. El Laboratorio Europeo de Referencia para las Alternativas a la Experimentación con Animales (EURL-EURL- ECVAM) es el laboratorio de referencia en Europa encargado de validar los métodos alternativos. Posteriormente pueden ser homologados por la Organización de Cooperación y Desarrollo Económico (OCDE). Por otro lado, el Comité Científico de Seguridad de los Consumidores (SCCS) asesora a la Comisión sobre todos los temas relacionados con la seguridad de los cosméticos. En esta revisión se detalla una relación de métodos alternativos necesarios para evaluar la seguridad de los ingredientes cosméticos así como los métodos usados y sus limitaciones.
Resumo:
The preparation of [FeIV(O)(MePy2tacn)]2+ (2, MePy2tacn = N-methyl-N,N-bis(2-picolyl)-1,4,7-triazacyclononane) by reaction of [FeII(MePy2tacn)(solvent)]2+ (1) and PhIO in CH3CN and its full characterization are described. This compound can also be prepared photochemically from its iron(II) precursor by irradiation at 447 nm in the presence of catalytic amounts of [Ru II(bpy)3]2+ as photosensitizer and a sacrificial electron acceptor (Na2S2O8). Remarkably, the rate of the reaction of the photochemically prepared compound 2 toward sulfides increases 150-fold under irradiation, and 2 is partially regenerated after the sulfide has been consumed; hence, the process can be repeated several times. The origin of this rate enhancement has been established by studying the reaction of chemically generated compound 2 with sulfides under different conditions, which demonstrated that both light and [Ru II(bpy)3]2+ are necessary for the observed increase in the reaction rate. A combination of nanosecond time-resolved absorption spectroscopy with laser pulse excitation and other mechanistic studies has led to the conclusion that an electron transfer mechanism is the most plausible explanation for the observed rate enhancement. According to this mechanism, the in-situ-generated [RuIII(bpy)3] 3+ oxidizes the sulfide to form the corresponding radical cation, which is eventually oxidized by 2 to the corresponding sulfoxide
Resumo:
Brugada syndrome (BrS) is a life-threatening, inherited arrhythmogenic syndrome associated with autosomal dominant mutations in SCN5A, the gene encoding the cardiac Na₊ channel alpha subunit (Naᵥ1.5). The aim of this work was to characterize the functional alterations caused by a novel SCN5A mutation, I890T, and thus establish whether this mutation is associated with BrS. The mutation was identified by direct sequencing of SCN5A from the proband’s DNA. Wild-type (WT) or I890T Naᵥ1.5 channels were heterologously expressed in human embryonic kidney cells. Sodium currents were studied using standard whole cell patch-clamp protocols and immunodetection experiments were performed using an antibody against human Naᵥ1.5 channel. A marked decrease in current density was observed in cells expressing the I890T channel (from -52.0 ± 6.5 pA/pF, n=15 to 35.9 ± 3.4 pA/pF, n = 22, at -20 mV, WT and I890T, respectively). Moreover, a positive shift of the activation curve was identified (V½ =-32.0 ± 0.3 mV, n = 18, and -27.3 ± 0.3 mV, n = 22, WT and I890T, respectively). No changes between WT and I890T currents were observed in steady-state inactivation, time course of inactivation, slow inactivation or recovery from inactivation parameters. Cell surface protein biotinylation analyses confirmed that Nav1.5 channel membrane expression levels were similar in WT and I890T cells. In summary, our data reveal that the I890T mutation, located within the pore of Nav1.5, causes an evident loss-of-function of the channel. Thus, the BrS phenotype observed in the proband is most likely due to this mutation
DUODES: Paraules clau d'història de les dones a Catalunya, segles IX-XVIII: una proposta de tesaurus
Resumo:
Sobre una proposta de tesaurus amb les paraules clau d'història de les dones de Catalunya dels segles IX a XVIII, realitzat per les dones de les seccions d'Història Medieval i Moderna del Centre d'lnvestigació Històrica de la Dona de la Universitat de Barcelona (DUODA)
Resumo:
Sobre la configuració general d'una proposta de tesaurus amb les paraules clau d'història de les dones de Catalunya dels segles IX a XVIII, realitzat per les dones de les seccions d'Història Medieval i Moderna del Centre d'lnvestigació Històrica de la Dona de la Universitat de Barcelona (DUODA)
Resumo:
Psychometric analysis of the AF5 multidimensional scale of self-concept in a sample of adolescents and adults in Catalonia. The aim of this study is to carry out a psychometric study of the AF5 scale in a sample of 4.825 Catalan subjects from 11 to 63 years-old. They are students from secondary compulsory education (ESO), from high school, middle-level vocational training (CFGM) and from the university. Using a principal component analysis (PCA) the theoretical validity of the components is established and the reliability of the instrument is also analyzed. Differential analyses are performed by gender and normative group using a 2 6 factorial design. The normative group variable includes the different levels classifi ed into 6 sub-groups: university, post-compulsory secondary education (high school and CFGM), 4th of ESO, 3rd of ESO, 2nd of ESO and 1st of ESO. The results indicate that the reliability of the Catalan version of the scale is similar to the original scale. The factorial structure also fi ts with the original model established beforehand. Signifi cant differences by normative group in the four components of self-concept explored (social, family, academic/occupational and physical) are observed. By gender, signifi cant differences appear in the component of physical self-concept, academic and social but not in the family component
Resumo:
A menudo es el podólogo quien debe enfrentarse a lesiones que se cronifican y que, en ocasiones, se asocian a afecciones de origen metabólico como la diabetes mellitus; desempeñando un importante papel para prevenir algunas de sus complicaciones. A pesar de ello, una vez que la lesión aparece, conseguir su cicatrización supone un reto complicado. El objetivo principal del presente artículo es aportar una perspectiva de abordaje local basado en la adecuada valoración y preparación de las características del lecho de la herida puesto que, independientemente del origen y etiología, su aspecto y características son de gran utilidad para la planificación de la estrategia terapéutica a seguir. A este respecto, el ¿concepto TIME¿ posibilita la correcta preparación del lecho de la herida mediante el empleo de productos de cura en ambiente húmedo que contribuyen a eliminar las barreras que dificultan el proceso natural de cicatrización.
Resumo:
A menudo es el podólogo quien debe enfrentarse a lesiones que se cronifican y que, en ocasiones, se asocian a afecciones de origen metabólico como la diabetes mellitus; desempeñando un importante papel para prevenir algunas de sus complicaciones. A pesar de ello, una vez que la lesión aparece, conseguir su cicatrización supone un reto complicado. El objetivo principal del presente artículo es aportar una perspectiva de abordaje local basado en la adecuada valoración y preparación de las características del lecho de la herida puesto que, independientemente del origen y etiología, su aspecto y características son de gran utilidad para la planificación de la estrategia terapéutica a seguir. A este respecto, el"concepto TIME" posibilita la correcta preparación del lecho de la herida mediante el empleo de productos de cura en ambiente húmedo que contribuyen a eliminar las barreras que dificultan el proceso natural de cicatrización.
Resumo:
El objetivo principal de este estudio es conocer el grado de concordancia entre los informes proporcionados por padres y maestros acerca de la sintomatología negativista desafiante en niños en edad escolar (6-8 años). Además, se pretende analizar si la edad y el sexo del niño afectan el nivel de acuerdo entre informantes. Padres y maestros evaluaron a 702 niños y niñas de 25 escuelas de la Comarca de Osona, Barcelona (España), mediante el Child Sympton Inventory-4 (versión padres y maestros). Los resultados indican una concordancia muy baja, casi nula, entre las valoraciones de ambos informantes; además, las variables edad y sexo de los niños no representan una diferencia significativa en dichas valoraciones. Los padres tienden a evaluar más síntomas del Trastorno Negativista Desafiante como presentes, y a percibir con mayor intensidad su severidad
Resumo:
SPME-GC-MS, PCA and HCA multivariate techniques were used in order to evaluate their applicability to discriminate the three chemotypes (thymol, carvacrol and mixed) described for L. graveolens of Guatemala. The leaves of L. graveolens are used for treatment of colds, bronchitis, and as seasoning for food preparations, yielding essential oil up to 4.34 %. Leaves of 35 individuals from eight populations, and eight composite samples were analyzed using a DVB/Carboxen/PDMS fiber and GC-MS. PCA and HCA were carried out using eight markers (p-cymene, cis-sabinene hydrate, linalool, terpinen-4-ol, thymol, carvacrol, (E)-caryophyllene and caryophyllene oxide). The three chemotypes of L. graveolens were satisfactorily discriminated.
LOW COST ANALYZER FOR THE DETERMINATION OF PHOSPHORUS BASED ON OPEN-SOURCE HARDWARE AND PULSED FLOWS
Resumo:
The need for automated analyzers for industrial and environmental samples has triggered the research for new and cost-effective strategies of automation and control of analytical systems. The widespread availability of open-source hardware together with novel analytical methods based on pulsed flows have opened the possibility of implementing standalone automated analytical systems at low cost. Among the areas that can benefit from this approach are the analysis of industrial products and effluents and environmental analysis. In this work, a multi-pumping flow system is proposed for the determination of phosphorus in effluents and polluted water samples. The system employs photometric detection based on the formation of molybdovanadophosphoric acid, and the fluidic circuit is built using three solenoid micropumps. The detection is implemented with a low cost LED-photodiode photometric detection system and the whole system is controlled by an open-source Arduino Uno microcontroller board. The optimization of the timing to ensure the color development and the pumping cycle is discussed for the proposed implementation. Experimental results to evaluate the system behavior are presented verifying a linear relationship between the relative absorbance and the phosphorus concentrations for levels as high as 50 mg L-1.
Resumo:
Neste artigo argumentamos que os temas da ação e da história presentes em alguns contos de Jorge Luis Borges antecipam alguns pontos que apareceram nas discussões pós-estruturalistas - nos campos da história, filosofia, antropologia - das últimas décadas do século XX. No seu labirinto literário-filosófico, especialmente por meio da ideia de destino, Borges explora elementos chave que se tornaram parte da noção de crítica que enfatiza as ideias de contingência e da impossibilidade de controle deliberado dos efeitos da ação humana em seu curso temporal.