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Actitudes de los consumidores hacia las recomendaciones online realizadas por lo social media influencers
(Universidad de Chile, 2018-07)
El endorsement ha sido una técnica utilizada con frecuencia en las comunicaciones de marketing. Esta táctica consiste en el uso de una persona o personaje como soporte de comunicación para una marca o producto, en el cual el endorser puede...
Caracterización de la arquitectura litosférica a los 23°S (Región de Antofagasta, Chile) mediante magnetotelúrica
(Universidad de Chile, 2020)
Un perfil de 200 km de magnetotelúrica (MT) fue realizado a los 23°S, en la zona oriental de la región de Antofagasta, en el norte de Chile. Diecisiete estaciones de periodo largo y seis estaciones de banda ancha fueron instaladas en distintas...
Curvas de atenuación para terremotos intraplaca e interplaca en la zona de subducción chilena
(Universidad de Chile, 2016)
La zona de subducción en Chile se caracteriza por poseer una actividad sísmica mayor en comparación con otras partes del mundo, con terremotos de gran magnitud cuyas zonas afectadas varían en función del contacto sismogénico y la profundidad a la...
Parrandera, Rebelde y Atrevida. Un análisis feminista de la música de la “Diva de la banda” Jenni Rivera
(Universidad de Chile, 2017)
La presente investigación es un análisis feminista de la música de la “diva de la Banda, Jenni Rivera, que fue realizado por Ana Laura Gamboa Muñoz bajo la guía académica de la Dra. Sonia Montecino, para la obtención del grado de Magister de Género...
Susceptibilidad de Porhyromonas gingivalis proveniente de pacientes con periodontitis crónica a los péptidos catiónicos polimixina B y beta defensinas humanas -1, -2, -3, y -4 y el posible papel del lipopolisacárido en su resistencia
(Universidad de Chile, 2016)
de microorganismos patógenos y la respuesta inmunológica desencadenada que conducen a la destrucción de los tejidos de inserción de los dientes, como son el hueso alveolar, el ligamento periodontal y el cemento radicular, resultan finalmente en la...
Periodontitis is an infectious disease with a chronic inflammatory component that occurs as result from imbalance between microorganisms forming biofilm and subgingival host immune response. Pathogenic microorganisms colonization and the immune response elicited lead to destruction of teeth insertion tissue such as: alveolar bone, periodontal ligament and cementum, finally resulting in tooth loss. The presence of specific Gram-negative anaerobic bacteria in subgingival biofilm is relevant for the etiology and progression of periodontitis. Among them, Porphyromonas gingivalis (P. gingivalis) is a "key" pathogen for the onset of periodontal disease. Although present in diseased sites in low abundance compared to the total oral microbiota, this bacterium is able to induce changes in the oral microbiome and cause dysbiosis, leading to development of periodontitis. P. gingivalis is the bacteria most frequently isolated in patients with chronic periodontitis and has been linked to progression of disease. However, it is unclear how their presence in healthy individuals is not associated with disease and the mechanisms for the development and/or progression of periodontitis have not been completely understood. Among P. gingivalis virulence factors the LPS noted for its structural changes conferring the ability to orchestrate and subvert the host immune response, and to resist endogenous peptides antimicrobial activity, such as defensins (hBDs). P. gingivalis reduces its electrostatic interaction with cationic peptides as Polymyxin B (PMB) and increases resistance by phosphatase lipid A 4´dephosphorylation (PGN_0524 gene). Besides modify their lipid A, P. gingivalis synthesizes two different types of LPS (A-LPS and O-LPS) differing at region of polymeric O antigen (OAg and APS, respectively). Several studies suggest that relevance for lipid A in PMB resistance, but its relationship with other cationic peptides resistance, relevant in the oral cavity (hBDs) has not been studied, and the possible role for the other known structures in LPS, such as APS and OAg in resistance. By the above, the present work proposed to determine the susceptibility of P. gingivalis clinical isolates, from chronic periodontitis (P. chronic) patients and periodontally healthy individuals to PMB and evaluate participation of lipid A 4' phosphatase in resistance to PMB and hBDs-1 to -4. In addition, the role of other regions of LPS as OAg and/or APS in resistance to cationic peptides was evaluated using as a model the PMB. Our results showed that isolates of P. gingivalis from P. chronic patients are more resistant to PMB respect from healthy individuals. Furthermore, healthy isolates are less resistant to PMB respect to the reference strain ATCC 33277. While, a mutant lacking phosphatase gene in the lipid A 4' position is totally susceptible to PMB, the presence of this gene in isolates does not correlate with the differential resistant observed since all isolates had the gene. Moreover, the lipid A structural analysis of the isolates shown 4' phosphorylated structures in both, susceptible and resistant PMB isolates, suggesting that P. gingivalis lipid A composition is not the only determining factor in clinical isolates PMB resistance, and probably to other cationic peptides, since the mutant was able to grow even to highest hBDs-1 to -4 concentrations. In healthy subject isolates lacked high molecular weight OAg and APS molecules, suggesting that P. gingivalis in healthy individuals do not produce or lose A-LPS. Finally, P. chronic isolates lacked APS molecules, suggesting that OAg and APS molecules are relevant in P. gingivalis resistance to cationic peptides PMB and hBDs -1 to -4...
Periodontitis is an infectious disease with a chronic inflammatory component that occurs as result from imbalance between microorganisms forming biofilm and subgingival host immune response. Pathogenic microorganisms colonization and the immune response elicited lead to destruction of teeth insertion tissue such as: alveolar bone, periodontal ligament and cementum, finally resulting in tooth loss. The presence of specific Gram-negative anaerobic bacteria in subgingival biofilm is relevant for the etiology and progression of periodontitis. Among them, Porphyromonas gingivalis (P. gingivalis) is a "key" pathogen for the onset of periodontal disease. Although present in diseased sites in low abundance compared to the total oral microbiota, this bacterium is able to induce changes in the oral microbiome and cause dysbiosis, leading to development of periodontitis. P. gingivalis is the bacteria most frequently isolated in patients with chronic periodontitis and has been linked to progression of disease. However, it is unclear how their presence in healthy individuals is not associated with disease and the mechanisms for the development and/or progression of periodontitis have not been completely understood. Among P. gingivalis virulence factors the LPS noted for its structural changes conferring the ability to orchestrate and subvert the host immune response, and to resist endogenous peptides antimicrobial activity, such as defensins (hBDs). P. gingivalis reduces its electrostatic interaction with cationic peptides as Polymyxin B (PMB) and increases resistance by phosphatase lipid A 4´dephosphorylation (PGN_0524 gene). Besides modify their lipid A, P. gingivalis synthesizes two different types of LPS (A-LPS and O-LPS) differing at region of polymeric O antigen (OAg and APS, respectively). Several studies suggest that relevance for lipid A in PMB resistance, but its relationship with other cationic peptides resistance, relevant in the oral cavity (hBDs) has not been studied, and the possible role for the other known structures in LPS, such as APS and OAg in resistance. By the above, the present work proposed to determine the susceptibility of P. gingivalis clinical isolates, from chronic periodontitis (P. chronic) patients and periodontally healthy individuals to PMB and evaluate participation of lipid A 4' phosphatase in resistance to PMB and hBDs-1 to -4. In addition, the role of other regions of LPS as OAg and/or APS in resistance to cationic peptides was evaluated using as a model the PMB. Our results showed that isolates of P. gingivalis from P. chronic patients are more resistant to PMB respect from healthy individuals. Furthermore, healthy isolates are less resistant to PMB respect to the reference strain ATCC 33277. While, a mutant lacking phosphatase gene in the lipid A 4' position is totally susceptible to PMB, the presence of this gene in isolates does not correlate with the differential resistant observed since all isolates had the gene. Moreover, the lipid A structural analysis of the isolates shown 4' phosphorylated structures in both, susceptible and resistant PMB isolates, suggesting that P. gingivalis lipid A composition is not the only determining factor in clinical isolates PMB resistance, and probably to other cationic peptides, since the mutant was able to grow even to highest hBDs-1 to -4 concentrations. In healthy subject isolates lacked high molecular weight OAg and APS molecules, suggesting that P. gingivalis in healthy individuals do not produce or lose A-LPS. Finally, P. chronic isolates lacked APS molecules, suggesting that OAg and APS molecules are relevant in P. gingivalis resistance to cationic peptides PMB and hBDs -1 to -4...
Implicancias del Síndrome Premenstrual en el quehacer laboral y relacional, en una muestra de Técnicos en Párvulo y Educadoras de Párvulo de la Junta Nacional de Jardines Infantiles
(Universidad de Chile, 2013)
representación del inconsciente colectivo, los que determinan una serie de
comportamientos y acciones. Estos, “acumulados en la memoria histórica del
género humano, están impregnados de matices tan variados como la religión, la
mitología, los valores, las...
de algo que no se muestra por medio de lo que vemos (21), de lo evidente. Esto que parece un juego de palabras, da cuenta de lo imbricado que puede resultar el estudio del ser humano, de la enfermedad y del sufrimiento, entendiéndola como una...
de algo que no se muestra por medio de lo que vemos (21), de lo evidente. Esto que parece un juego de palabras, da cuenta de lo imbricado que puede resultar el estudio del ser humano, de la enfermedad y del sufrimiento, entendiéndola como una...
Aplicación de algoritmos evolutivos multi-objetivo al diseño de empaquetamientos de baterías
(Universidad de Chile, 2013)
Las baterías de ion-litio son las más usadas actualmente para los vehículos eléctricos y para respaldo en sistemas eléctricos de potencia. Sin embargo, aún presentan altos costos y una baja vida útil con respecto a lo esperado por el mercado y los...
Catastro y registro de la distribución de patógenos identificados en mamíferos nativos amenazados de Chile, asociándolos al Sistema Nacional de Areas Silvestres Protegidas del Estado
(Universidad de Chile, 2018)
El Sistema Nacional de Áreas Silvestres Protegidas del Estado de Chile (SNASPE), administrado por la Corporación Nacional Forestal (CONAF), representa el 20% de la superficie de Chile y cobija al 87% de las especies de fauna vertebrada del país...
The National System of Protected Wild Areas of the State of Chile (SNASPE), administered by the National Forestry Corporation (CONAF), represents 20% of the The National System of Protected Wild Areas of the State of Chile (SNASPE), the administrator of the National Forestry Corporation (CONAF), represents 20% of the surface of Chile and 87% of the species of vertebrate fauna of the country, assuming great importance in the field of in situ conservation of the endemic and native fauna of the national territory. One of the threats of importance to wildlife is the presence of transmissible diseases and transmission of pathogens, information on the relationships of animals and/or the introduction of invasive exotic species to the Protected Wildlife Areas (ASP), among others. Factors There are numerous scientific investigations that account for pathogens present in wildlife, however, not all of these reports are gathered in a single document. The objective of this study is to generate a cadastre and a register of the distribution of pathogens in the threatened native animals of Chile, associating them with the National System of Protected Wild Areas of the State. The methodology was carried out in four stages: 1) Selection of species of native animals present in ASP, which will be presented in some degree of threat, according to their category of life care services, 2) Cadastre and systematization of the pathogens in the selected native mammals, according to the specific criteria, 3) Georeferencing of the pathogens in the selected native mammals, associating each record in the closest ASP, and 4) Generation of cartographic maps of the presence of pathogens by species. A total of 135 reports of pathogens in 10 mammal species will be collected, recording 41 different types of pathogens, associated with 21 ASPs. The most relevant pathogens in the species studied were: Corynebacterium pseudotuberculosis in Hippocamelus bisulcus, Mycobacterium avium, susp. paratuberculosis in Pudu pudu and Lama guanicoe, Canine Parvovirus and Canine Distemper Virus in Lycalopex sp., Sarcoptes scabiei in Vicugna vicugna and Feline Leukemia Virus and Feline Immunodeficiency Virus in Leopardus guigna, among others. Most of the registered pathogens are also found in domestic animals, which may suggest that they play an important role in the persistence of these pathogens in wild animal populations. It is concluded that more studies are necessary to better understand the epidemiology of pathogens present in wildlife and the real effect and influence of domestic animals on health in natural spaces, being able to be powerful factors that are gradually altering the normal equilibrium of the ecosystems and, consequently, the health and conservation of wild animal species native to the country...
The National System of Protected Wild Areas of the State of Chile (SNASPE), administered by the National Forestry Corporation (CONAF), represents 20% of the The National System of Protected Wild Areas of the State of Chile (SNASPE), the administrator of the National Forestry Corporation (CONAF), represents 20% of the surface of Chile and 87% of the species of vertebrate fauna of the country, assuming great importance in the field of in situ conservation of the endemic and native fauna of the national territory. One of the threats of importance to wildlife is the presence of transmissible diseases and transmission of pathogens, information on the relationships of animals and/or the introduction of invasive exotic species to the Protected Wildlife Areas (ASP), among others. Factors There are numerous scientific investigations that account for pathogens present in wildlife, however, not all of these reports are gathered in a single document. The objective of this study is to generate a cadastre and a register of the distribution of pathogens in the threatened native animals of Chile, associating them with the National System of Protected Wild Areas of the State. The methodology was carried out in four stages: 1) Selection of species of native animals present in ASP, which will be presented in some degree of threat, according to their category of life care services, 2) Cadastre and systematization of the pathogens in the selected native mammals, according to the specific criteria, 3) Georeferencing of the pathogens in the selected native mammals, associating each record in the closest ASP, and 4) Generation of cartographic maps of the presence of pathogens by species. A total of 135 reports of pathogens in 10 mammal species will be collected, recording 41 different types of pathogens, associated with 21 ASPs. The most relevant pathogens in the species studied were: Corynebacterium pseudotuberculosis in Hippocamelus bisulcus, Mycobacterium avium, susp. paratuberculosis in Pudu pudu and Lama guanicoe, Canine Parvovirus and Canine Distemper Virus in Lycalopex sp., Sarcoptes scabiei in Vicugna vicugna and Feline Leukemia Virus and Feline Immunodeficiency Virus in Leopardus guigna, among others. Most of the registered pathogens are also found in domestic animals, which may suggest that they play an important role in the persistence of these pathogens in wild animal populations. It is concluded that more studies are necessary to better understand the epidemiology of pathogens present in wildlife and the real effect and influence of domestic animals on health in natural spaces, being able to be powerful factors that are gradually altering the normal equilibrium of the ecosystems and, consequently, the health and conservation of wild animal species native to the country...
La transformación de la intimidad de las familias chilenas y costarricenses en el contexto del modelo neoliberal de modernización: 1973-2013
(Universidad de Chile, 2014)
interventora en la economía, centrándose especialmente en las
políticas macroeconómicas y en los problemas de pobreza más extrema. Esta política
estuvo sustentada a través de diversos recursos administrativos, jurídicos, policiales y no
permitió ningún tipo de...
UNIVERSIDAD DE CHILE FACULTAD DE FILOSOFÍA Y HUMANIDADES ESCUELA DE POSTGRADO LA TRANSFORMACIÓN DE LA INTIMIDAD DE LAS FAMILIAS CHILENAS Y COSTARRICENSES EN EL CONTEXTO DEL MODELO NEOLIBERAL DE MODERNIZACIÓN: 1973...
UNIVERSIDAD DE CHILE FACULTAD DE FILOSOFÍA Y HUMANIDADES ESCUELA DE POSTGRADO LA TRANSFORMACIÓN DE LA INTIMIDAD DE LAS FAMILIAS CHILENAS Y COSTARRICENSES EN EL CONTEXTO DEL MODELO NEOLIBERAL DE MODERNIZACIÓN: 1973...
Videojuego para la construcción de un modelo mental de un sistema de referencias para personas ciegas
(Universidad de Chile, 2013)
Una persona con visión normal puede notar a diario, que existen variadas actividades que requieren como sentido principal la visión, para poder ser realizadas de manera satisfactoria. En este sentido, la adopción de un modelo mental que les permite...