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Search Results: 1 - 10 of 20407 matches for " Andrea Duarte Cordero "
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Preceptos de la ideología patriarcal asignados al género femenino y masculino, y su refractación en ocho cuentos utilizados en el tercer ciclo de la educación general básica del sistema educativo costarricense en el a o 2005
Rodolfo Fernández Carballo,Andrea Duarte Cordero
Educación , 2006,
Abstract: En este artículo se realiza una enumeración de los diversos preceptos que la ideología patriarcal asigna a los géneros femenino y masculino, y se pretende demostrar, a partir de las concepciones teóricas de Bajtín sobre las relaciones texto-sociedad, el enunciado y las valoraciones sociales, cómo dichos preceptos se refractan en ocho cuentos de lectura obligatoria utilizados por los estudiantes del Tercer Ciclo de la Educación General Básica del Sistema Educativo Costarricense en el a o 2005. Finalmente, se establecen, en la conclusión, algunas recomendaciones en torno al tema tratado por su incidencia en la formación de los estudiantes.
Rock1 Inhibitor Abrogates Chronic Rejection in Rat Cardiac Model System  [PDF]
Li Zhang, Malgorzata Kloc, Neelam Tejpal, Junping You, Andrea M. Cordero-Reyes, Keith A. Youker, Rafik M. Ghobrial
Open Journal of Organ Transplant Surgery (OJOTS) , 2012, DOI: 10.4236/ojots.2012.24012
Abstract: Background: We have shown previously that the abrogation of acute and chronic rejection of rat cardiac allografts occurs through the down-regulation of RhoA pathway and involves the changes in RhoA kinase (ROCK)-dependent actin cytoskeleton and T cell motility. Here we studied the ability of the Y-27632, a highly selective inhibitor of Rho-associated protein kinase p160ROCK (ROCK1), to abrogate chronic rejection of the allograft and influence T cell infiltration. Methods: Heterotopic cardiac transplants were performed between donor Wistar Furth (WF) and ACI recipient rats. Controls received sub-therapeutic dose of cyclosporine (CsA, 10 mg/kg) for 3 days or 7 days therapeutic dose of cyclosporine. The experimental groups of ACI recipient received one preoperative dose of the Y-27632 inhibitor (2 mg/kg, gavage feed) in conjunction with the sub-therapeutic dose of CsA for 3 days or inhibitor alone for 7 days. The cardiac grafts were harvested at 100 days of post-transplantation for histological and immunohistochemical assessment of chronic rejection, vascular sclerosis, and infiltration by different T cell subtypes. Results: Cardiac allografts from recipients exposed to Y-27632 inhibitor in conjunction with sub-therapeutic dose of CsA showed drastically reduced vascular sclerosis, minimal myocardial total cellular infiltration, and were selectively infiltrated with Foxp3+ T regulatory (Treg) cells. Conclusions: Our novel finding that a single dose of the ROCK1 inhibitor Y-27632 attenuates chronic rejection in rat cardiac model system by promoting development of Treg cells warrants its potential as a novel therapeutic agent specific for the inhibition of chronic rejection.
Cycloaddition Reactions of C,N-Diphenylnitrone to Methylene-γ-butyrolactones
Martina Cacciarini,Franca M. Cordero,Cristina Faggi,Andrea Goti
Molecules , 2000, DOI: 10.3390/50400637
Abstract: Cycloaddition of C,N-diphenylnitrone to α-methylene-γ-butyrolactone afforded two diastereomeric 5-spirosubstituted isoxazolidines with high selectivity. Structural assignment was ascertained by NMR studies and an X-ray diffraction experiment on a single crystal of the major isomer and the diastereoselectivity was rationalized on examination of the alternative transition states leading to the two diastereoisomers.
Produ??o e análise de vídeograva??es em pesquisas qualitativas
Garcez, Andrea;Duarte, Rosalia;Eisenberg, Zena;
Educa??o e Pesquisa , 2011, DOI: 10.1590/S1517-97022011000200003
Abstract: one of the criticisms made about empirical studies of a qualitative basis concerns the inappropriate use of research methodologies as a result of a less than careful match between the research object/problem and the data production procedures. a fact often neglected is that the adoption of a given methodology is dictated by what is necessary to do in order to obtain empirical material whose density and wealth allows a better understanding of the different aspects surrounding the problem under investigation, so that well grounded hypotheses can be formulated. it is up to the researcher to choose the method best suited to the gathering of the data and to the theoretical assumptions guiding it, and to that purpose he/she must have knowledge of the various choices available. this article presents reflections and guidelines about the ever more frequent use of video recordings in qualitative research, discussing specificities of the production and analysis of audiovisual material associated to investigation procedures in social and human sciences. the considerations put forward here were built from the experience in the use of this kind of resource in studies carried out by the authors during the last five years, in constant dialogue with publications by other researchers who, having also worked with this resource, describe in their texts the difficulties and solutions related to its adoption. it is hoped that this will contribute to the debate on the necessary and close correlation between object and method in empirical studies.
A Straightforward Route to Enantiopure Pyrrolizidines and Indolizidines by Cycloaddition to Pyrroline N-Oxides Derived from the Chiral Pool
Andrea Goti,Stefano Cicchi,Franca M. Cordero,Valentina Fedi,Alberto Brandi
Molecules , 1999, DOI: 10.3390/40100001
Abstract: Enantiomerically pure, five membered cyclic nitrones, easily obtained in large amounts from protected hydroxyacids and aminoacids such as D- and L-tartaric, L-malic, and L-aspartic acids, give cycloaddition reactions with a good diastereocontrol. The adducts of L-malic and L-aspartic acids derived from addition of nitrones to dimethyl maleate and g-crotonolactone were easily converted into enantiopure pyrrolizidinones, which can be transformed into polyhydroxypyrrolidines or polyhydroxypyrrolizidines, both interesting compounds as potential glycosidase inhibitors. The method is suitable for natural products synthesis as exemplified by a straightforward and convenient access to the pyrrolizidine alkaloid necine base (–)-hastanecine, as well as to indolizidine alkaloids, i.e. (+)- lentiginosine.
Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica
Martínez-Fernández,Damián; Montero-Cordero,Andrea; May-Collado,Laura;
Revista de Biología Tropical , 2011,
Abstract: inshore cetaceans from the north and south pacific coast of costa rica. twenty nine cetacean species occur in costa rican waters but extensive research has been conducted only for three species. the latter shows there is a lack of general and local information about these mammals, even when the country, has shown a remarkable growth in whale watching activities. the increasing use of marine resources in coastal areas has also developed the need to determine the occurrence of cetaceans in areas showing high tourist presence, in order to propose sound conservation measures. in this study, environmental variables were determined and subsequently related to the presence of the species recorded, out of 166 sightings, between 2005 and 2006. the species with highest proportion of sightings were stenella attenuata (68%), followed by megaptera novaeangliae (13%) and tursiops truncatus (10%). the presence of spotted dolphins is related to changes in salinity and water transparency, while that of the humpback whale was related to wave height (beaufort scale) and water temperature. the presence of seven species of cetaceans was confirmed in two coastal areas of the pacific coast of costa rica, from which three are present throughout the year. environmental variables were found related to the presence of at least two species. rev. biol. trop. 59 (1): 283-290. epub 2011 march 01.
Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica
Damián Martínez-Fernández,Andrea Montero-Cordero,Laura May-Collado
Revista de Biología Tropical , 2011,
Abstract: De las 29 especies de cetáceos presentes en Costa Rica, se han realizado investigaciones exhaustivas solamente para tres especies. Lo anterior evidencia la poca información general existente sobre cetáceos, a pesar de que Costa Rica posee un notable crecimiento de actividades de avistamiento. Debido al uso que se está generando en las zonas costeras, cada vez se hace más necesario determinar la ocurrencia de cetáceos en zonas de alta actividad turística, con el fin de proponer medidas de conservación. En el presente estudio, se determinaron variables ambientales que estaban relacionadas con la presencia de especies registradas, a partir de 166 avistamientos entre el 2005 y 2006. Las especies con mayor proporción de avistamientos fueron Stenella attenuata (68%), seguida por Megaptera novaeangliae (13%) y Tursiops truncatus (10%). La presencia del delfín manchado se relaciona con cambios de salinidad y trasparencia del agua, mientras que la de la ballena jorobada estuvo relacionada con el oleaje y la temperatura superficial del agua. Se confirma la presencia de 7 especies de cetáceos en dos zonas costeras del Pacífico de Costa Rica, de las cuales tres están presentes a lo largo del a o. Se encontraron variables ambientales relacionadas con la presencia de al menos dos especies. Inshore cetaceans from the North and South Pacific coast of Costa Rica. Twenty nine cetacean species occur in Costa Rican waters but extensive research has been conducted only for three species. The latter shows there is a lack of general and local information about these mammals, even when the country, has shown a remarkable growth in whale watching activities. The increasing use of marine resources in coastal areas has also developed the need to determine the occurrence of cetaceans in areas showing high tourist presence, in order to propose sound conservation measures. In this study, environmental variables were determined and subsequently related to the presence of the species recorded, out of 166 sightings, between 2005 and 2006. The species with highest proportion of sightings were Stenella attenuata (68%), followed by Megaptera novaeangliae (13%) and Tursiops truncatus (10%). The presence of spotted dolphins is related to changes in salinity and water transparency, while that of the humpback whale was related to wave height (Beaufort scale) and water temperature. The presence of seven species of cetaceans was confirmed in two coastal areas of the Pacific coast of Costa Rica, from which three are present throughout the year. Environmental variables were found related to the p
Sitagliptina, un inhibidor de la enzima DPP-IV, aumenta el colesterol plasmático total, altera el perfil de colesterol lipoproteico y disminuye el transporte reverso de colesterol en ratones Sitagliptine, an DPP-IV enzyme inhibitor, raises total cholesterol and decreases reversal cholesterol transport in mice
Andrea Leiva,Pablo Varas,Ludwig Amigo,Susana Contreras-Duarte
Revista Chilena de Cardiología , 2010,
Abstract: Antecedentes: Las hormonas insulina y glucagón regulan la expresión de proteínas claves en el metabolismo lipfdico. En pacientes diabéticos, la enfermedad cardiovascular ateroesclerótica es la principal causa de muerte, siendo la dislipidemia un importante factor de riesgo patogénico. La sitagliptina, un inhibidor de la enzima dipeptidilpeptidasa tipo IV (DPP-IV) que controla el metabolismo de las incretinas, es una nueva droga hipogli-cemiante utilizada para el tratamiento de la diabetes tipo 2, aunque sus implicancias en el metabolismo lipfdico no han sido establecidas claramente. Objetivo: Estudiar el efecto de la sitagliptina sobre algunos parámetros relacionados con el metabolismo del colesterol en el ratón. Material y Métodos: Se utilizaron ratones C57BL6/J silvestres, siendo un grupo alimentado con dieta estándar y el otro con dieta estándar suplementada con sitagliptina (0,6% P/Pde dieta) por 8 semanas. La actividad plasmática de DPP-IV y el colesterol plasmático total y lipoproteico fueron medidos por métodos enzima-ticos. La expresión hepática de SR-BI y LDLR se cuanti-ficó por western blot. El transporte reverso de colesterol (TRC) fue evaluado inyectando intraperitonealmente ma-crófagos cargados con colesterol-14C y midiendo posteriormente los niveles de 14C en plasma y deposiciones en los ratones controles o tratados con sitagliptina. Resultados: La sitagliptina inhibió en un 38% la actividad de DPP-IV medida en plasma de los ratones. El colesterol plasmático aumentó significativamente (+60%) con una elevación preferente del colesterol HDL en los ratones tratados con sitagliptina versus los animales controles. Con respecto al TRC, la sitagliptina indujo una mayor recuperación (+20%) en el plasma y una menor excresión (-30%) en las deposiciones del 14C-colesterol inyectado versus el grupo control. Finalmente, la sitagliptina disminuyó la expresión hepática de los receptores lipoproteicos LDLR y SR-BI. Conclusión: Estos resultados indican que la sitagliptina aumenta el colesterol plasmático total, predominantemente transportado en HDL, y disminuye el transporte reverso de colesterol y su excreción fecal, probablemente como consecuencia de la disminución en la expresión hepática de SR-BI. Dado el patrón proaterogénico observado, se requieren estudios adicionales para establecer el efecto de la sitagliptina sobre el desarrollo de ateroesclerosis en el ratón. Background: Insulin and glucagon regúlate the expression of key lipoprotein metabolism enzymes. Dyslipidemia is a significant risk factor for cardiovascular disease, the main cause of death
Educar en comunidad: Implica más que buena voluntad; es un espacio para celebrar la diversidad
Cordero Cordero, Teresita
Revista Electrónica Actualidades Investigativas en Educación , 2006,
Abstract: Resumen: El presente artículo plantea la discusión sobre una serie de acciones que se dan en el marco institucional e investigativo, relacionados con los estudios sobre la crianza infantil y el programa de los Hogares Comunitarios en Costa Rica. Estos abordajes no cumplen con una perspectiva integradora y menos involucran procesos de desarrollo humano sostenible. Para ello se apela al cambio de prácticas y de enfoques conceptuales. Se se alan limitaciones sobre las prácticas institucionales, así como se numera una serie de posibles acciones alternativas. Es un trabajo que cuestiona, no las intenciones, pero sí las prácticas institucionalizadas, lo que nos lleva a impulsar la creación de alternativas críticas, tarea que demanda de la acción conjunta. Por tal razón, el trabajo está abierto al debate.Abstract:The present article expounds the discussion of a series of actions that take place in the institutional and research framework related to studies on child rearing and the Community Homes Program in Costa Rica. These approaches do not posses an integrative perspective and do not involve sustainable human development processes. To address these problems, this work proposes a change in practices and of conceptual focus. It therefore points out limitations in the institutional practices and enumerates a series of possible alternative suggestions. This work questions not the intensions but rather the institutionalized practices, which requires the creation of critical alternatives, a task that demands joint actions. This work is open to debate and discussion.
La opinión de un grupo de docentes sobre la deserción escolar. Explorando sobre sus actuaciones en el contexto institucional / The opinion of a group of teachers about school desertion: exploring their acts in the institutional context
Cordero Cordero, Teresita
Revista Electrónica Actualidades Investigativas en Educación , 2008,
Abstract: Resumen: El trabajo indagó con un grupo de docentes de cinco escuelas y un colegio costarricenses las acciones que suelen hacer ante la deserción escolar. Desde una perspectiva de investigación de corte cualitativo se organiza la información y se retoman estudios para presentar la problemática en el país. Se argumenta que la deserción es un problema multicausal, donde la organización de los centros educativos y las acciones que realiza el personal docente de las instituciones también viene contribuir con el problema.El estudio plantea en términos generales que como país tenemos una legislación avanzada para la ni ez y la adolescencia pero no hay una política clara sobre qué hacer en los casos de deserción. Si bien solamente se trabajó en un colegio parece existir una mejor respuesta en la primaria para retener o mantener al estudiantado.Lograr una organización eficiente de las instituciones escolares con respecto a cómo enfrentar la deserción podría ser una vía para mitigar esta problemática. Tarea que estaría pendiente y que debería ser trabajada desde el Ministerio de Educación Pública costarricense con el objetivo de incidir en la cultura institucional de las diferentes escuelas y colegios del país.Abstract:This work deals with a group of teachers from five schools and one high school in Costa Rica and their actions regarding school desertion. In order to present the current situation of this problem in Costa Rica, this information is organized and studies are restarted from the point of view of qualitative research. It is argued that desertion is a problem with multiple causes, where the organization of the education centers and the actions of the teacher staff compounds this issue.The study states in general terms that as a country, although we have advanced legislation in favor of children and adolescents, we do not have a clear policy for handling desertion. Despite we only worked with a single high school, we believe that there is a better response in primary school to the efforts at keeping students. Achieving an efficient organization of schools regarding how to deal with desertion could be the way to improve this problem.This is a pending task and it should be addressed by the Ministry of Public Education in Costa Rica, with the objetive of making an impact in the institutional culture of the different schools and high schools in the country.
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