High pressure investigation of superconducting signatures in CeCu2_{2}Si2_{2} : ac- magnetic susceptibility and heat capacity, resistivity and thermopower

Taking advantage of a novel multiprobe setup we have measured, on a unique sample, the ac-magnetic susceptibility, the resistivity, the ac-specific heat and the thermopower of the superconductor heavy fermion CeCu$_{2}$Si$_{2}$ under pressure up to 5.1 GPa. At the superconducting transition temperature $T_c$, the Meissner signal corresponds to that expected for the sample volume and coincides with the specific heat jump and the resistive transition completion temperatures. Differing from previous observations, here the susceptibility measurements did not reveal any anomaly in the vicinity of the resistive transition onset

Electromagnetic wave propagation along a wire parallel to a reactive surface

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Proteomics in alcohol research

The proteome is the complete set of proteins in an organism. It is considerably larger and more complex than the genome - the collection of genes that encodes these proteins. Proteomics deals with the qualitative and quantitative study of the proteome under physiological and pathological conditions (e.g., after exposure to alcohol, which causes major changes in numerous proteins of different cell types). To map large proteomes such as the human proteome, proteins from discrete tissues, cells, cell components, or biological fluids are first separated by high-resolution two-dimensional electrophoresis and multidimensional liquid chromatography. Then, individual proteins are identified by mass spectrometry. The huge amount of data acquired using these techniques is analyzed and assembled by fast computers and bioinformatics tools. Using these methods, as well as other technological advances, alcohol researchers can gain a better understanding of how alcohol globally influences protein st

Targeting kupffer cells with antisense oligonucleotides

© 2002 Frontiers in Bioscience. All rights reserved.During proinflammatory reactions such as endotoxemia, ischemia-reperfusion and immune reactions, excessive amounts of cytokines and prostanoids are released resulting in liver injury. In the liver, Kupffer cells are the primary source of cytokines and prostanoids. Obliteration of Kupffer cells prevents experimentally-induced liver damage, suggesting a major role for Kupffer in the pathogenesis of liver diseases. Pretreatment of experimental animals with antibodies directed against cytokines such as tumor necrosis alpha (TNF-alpha) prevented experimentally-induced liver damage. In recent years, antisense oligonucleotides (ASOs) directed against specific mRNAs have been tested as an alternative therapy to control the excessive production of inflammatory peptides. Although ASOs have great potential against gene expression, their design, in vivo delivery and stability, have posed significant challenges. Computer-aided configurational ana

Análisis de riesgo de las tarjetas de Retail en Chile

Tesis (Magíster en Finanzas)Hoy en día el mercado de tiendas de Retail de Chile ha crecido sostenidamente en el tiempo, logrando atraer las mayores inversiones del mercado. Por otra parte, los clientes que son partidarios del uso de tarjetas plásticas de las grandes multitiendas alcanzando alrededor de 13 millones, las cuales están repartidas a todo lo largo del país. De estos 13 millones de tarjetas que se encuentran distribuidas en todo el país, sólo el 81 % del segmento C3 y D usa para sus compras las tarjetas de grandes tiendas o supermercados. Nuestro estudio demostrará cómo podría acrecentarse el factor de riesgo de las tarjetas de Retail en Chile, ante un escenario económico de mayor incertidumbre, donde la capacidad de pago de los sujetos de crédito empeorará, ya que la situación mundial no es muy favorable en este mercado, porque habrá un menor poder adquisitivo de las personas. A raíz de esto, las empresas de Retail se verán obligadas a aumentar en gran medida sus provisiones, y quizás recortar más drásticamente sus planes de expansión

Genotyping of Mitochondrial Aldehyde Dehydrogenase Locus of Native American Indians

Using the polymerase chain reaction to amplify genomic DNA from hair roots, we have examined the mitochondrial aldehyde dehydrogenase (ALDH2) genotypes of 28 individuals from the South American Mapuche Indians. We have determined that individuals from this population previously reported to lack (ALDH2) activity do not show the presence of the inactive (ALDH22) allele frequently found in Orientals. Copyright © 1990, Wiley Blackwell. All rights reserve

Insulin is secreted upon glucose stimulation by both gastrointestinal enteroendocrine K-cells and L-cells engineered with the preproinsulin gene

Transgenic mice carrying the human insulin gene driven by the K-cell glucose-dependent insulinotropic peptide (GIP) promoter secrete insulin and display normal glucose tolerance tests after their pancreatic β-cells have been destroyed. Establishing the existence of other types of cells that can process and secrete transgenic insulin would help the development of new gene therapy strategies to treat patients with diabetes mellitus. It is noted that in addition to GIP secreting K-cells, the glucagon-like peptide 1 (GLP-1) generating L-cells share/ many similarities to pancreatic β-cells, including the peptidases required for proinsulin processing, hormone storage and a glucosestimulated hormone secretion mechanism. In the present study, we demonstrate that not only K-cells, but also L-cells engineered with the human preproinsulin gene are able to synthesize, store and, upon glucose stimulation, release mature insulin. When the mouse enteroendocrine STC-1 cell line was transfected with t

Effects of Ethanol on Hepatic Blood Flow in the Rat

Hepatic blood flow measured by indocyanine green clearance was studied in rats after an acute intoxicating dose of ethanol (2 g/kg) or after chronic ethanol administration by feeding with alcohol liquid diets. Acute intoxication to normal animals did not modify hepatic blood flow. In chronically alcohol‐fed rats, hepatic blood flow was significantly decreased when measured after 15 hr of abstinence. If ethanol was not withdrawn and an acute dose of ethanol was given before the indocyanine green clearance, a decreased hepatic blood flow was not observed. It is suggested that the reduction of hepatic blood flow in recently abstinent chronically alcohol‐treated animals is related to the withdrawal syndrome. Copyright © 1981, Wiley Blackwell. All rights reserve