Browsing by Author "Alvarez, M"

Now showing 1 - 4 of 4
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    An integrated model for earthquake risk assessment of buildings
    (ELSEVIER SCI LTD, 2002) Fischer, T; Alvarez, M; Llera Martin, Juan Carlos de la; Riddell, R
    This study is devoted to the formulation and construction of an integrated model for earthquake risk assessment of buildings in seismic regions. The model developed has five stages: i) characterization of ground motion, ii) construction of the building model, iii) evaluation of the inelastic building response, iv) structural damage assessment, and v) risk evaluation. Stages iii) and iv) are emphasized in the current presentation, because they include some newer aspects such as the use of story-shear and torque surfaces for inelastic building analysis and fuzzy logic for assessing the earthquake performance of a structure. Examples including a large building inventory and two individual structures are developed to show the potential use of the model. Results show that the model is capable of discriminating different foundation soils, earthquake performance of shear-wall and frame buildings, asymmetries in height and plan, and between conventional and seismically isolated structures. Such features may be useful to engineers working in city planning, emergency and risk management, and the insurance industry. (C) 2002 Elsevier Science Ltd. All rights reserved.
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    Determination of a BRCA1 gene mutation in a family with hereditary breast cancer
    (SOC MEDICA SANTIAGO, 2004) Gallardo, M; Faundez, P; Cruz, A; Rodriguez, M; Alvarez, M; Carvallo, P
    Background: Breast cancer is the main cause of death among fore, the women between 40 and 55 years old, in whom the hereditary cases are common. Therefore molecular diagnosis of germ line initiations involved in breast cancer susceptibilily is relevant. BRCA1 and BRCA2 have been described as the two major genes involved in familial breast/ovarian cancer. We are performing a screening for BRCA 1 and BRCA2 genes, in a group of 50 high risk Chilean families for breast/ovarian cancer. We have detected a mutation, 3936 C > T, that leads to a truncated protein, in two affected women from one of the families in study.
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    Down-regulation of endothelial adhesion molecules and leukocyte adhesion by treatment with superoxide dismutase is beneficial in chronic immune experimental colitis
    (OXFORD UNIV PRESS INC, 2005) Segui, J; Gil, F; Gironella, M; Alvarez, M; Gimeno, M; Coronel, P; Closa, D; Pique, JM; Panes, J
    Modulation of adhesion molecule expression that govern trafficking of leukocytes into the inflamed intestine is envisioned as a new strategy for treatment of inflammatory bowel disease (IBD). This study was designed to determine the impact of reducing oxidative stress on adhesion molecules expression and leukocyte recruitment in experimental chronic colitis. For that purpose, colitic interleukin-10 knockout and wild-type mice were studied. Groups of animals were treated with Cu/Zn superoxide dismutase (SOD1) 13 mg/kg/d or vehicle for either 7 or 14 days. Expression of vascular cell adhesion molecule-1 and mucosal addressin cell adhesion molecule-1 were determined; leukocyte-endothelial cell interactions in colonic venules were studied with intravital microscopy; and changes in colon pathology and biomarkers of colitis severity were determined. Development of colitis was associated with a marked increase in endothelial vascular cell adhesion molecule-1 and mucosal addressin cell adhesion molecule-1 expression, which were significantly reduced by treatment with SOD1 The increase in leukocyte rolling and adhesion in colonic venules of colitic mice were significantly reduced by administration of SOD1 This treatment markedly reduced colonic lipid hydroperoxidation, myeoloperoxidase activity, and plasma levels of serum amyloid A protein and resulted in significant, although modest, reductions in histologic damage score. The therapeutic value of SOD1 when administered prophylactically was assessed in the dextran sulfate sodium model of colitis with similar positive results. These results indicate that SOD1 affords significant amelioration of colonic inflammatory changes in experimental colitis. Down-regulation of adhesion molecule expression, reduction of lipid hydroperoxidation, and recruitment of leukocytes into the inflamed intestine contribute to this beneficial effect.
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    Use of methylene blue in patients with refractory septic shock: Impact on hemodynamics and gas exchange
    (W B SAUNDERS CO, 1998) Andresen, M; Dougnac, A; Diaz, O; Hernandez, G; Castillo, L; Bugedo, G; Alvarez, M; Dagnino, J
    Purpose: The purpose of this study was to assess the acute effects of methylene blue, an inhibitor of nitric oxide synthesis, on hemodynamics and gas exchange in patients with refractory septic shock in a prospective clinical trial at medical and surgical intensive care units in a tertiary university hospital.