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Estimación del azimut en eventos sísmicos utilizando Deep Learning
(Universidad de Chile, 2023)
La tarea de estimación de localización de eventos sísmicos es una labor de gran relevancia,
sobre todo en el contexto de los Sistemas de Alerta Temprana. Usualmente, para realizar dicha
estimación se utiliza la información registrada a partir de...
Conocimiento de madres de niños de hasta 71 meses de 3 comunas de bajos ingresos de la RM, en factores de riesgo de caries temprana de la infancia según factores sociodemográficos y acceso a educación en salud oral
(Universidad de Chile, 2014)
Riesgo de Caries Temprana de la Infancia
según Factores Sociodemográficos y Acceso a Educación en Salud Oral ".
Consuelo Alejandra Peña Durán
TRABAJO DE INVESTIGACIÓN
REQUISITO PARA OPTAR AL TÍTULO DE
CIRUJANO-DENTISTA
TUTOR PRINCIPAL
Prof...
CHILE FACULTAD DE ODONTOLOGÍA DEPARTAMENTO DEL NIÑO Y ORTOPEDIA DENTOMAXILAR " Conocimiento de madres de niños de hasta 71 meses de 3 comunas de bajos ingresos de la RM, en Factores de Riesgo de Caries Temprana de la Infancia según Factores...
CHILE FACULTAD DE ODONTOLOGÍA DEPARTAMENTO DEL NIÑO Y ORTOPEDIA DENTOMAXILAR " Conocimiento de madres de niños de hasta 71 meses de 3 comunas de bajos ingresos de la RM, en Factores de Riesgo de Caries Temprana de la Infancia según Factores...
Sistema didáctico de estimulación temprana para niños/as no videntes de 0 a 4 años, articulado por la figura materna
(Universidad de Chile, 2014)
..........................................................................................................................7
Condición de discapacidad visual en Chile .......................................................................................8
Estimulación temprana...
.........................................................................................................77 4Resumen El proyecto se desarrolla en el ámbito de la educación en el aula, específi camente en el nivel de estimulación temprana con el objetivo de fortalecer el desarrollo sensorio-motriz de niños/as (de 0 a 4 años) no videntes, a través de...
.........................................................................................................77 4Resumen El proyecto se desarrolla en el ámbito de la educación en el aula, específi camente en el nivel de estimulación temprana con el objetivo de fortalecer el desarrollo sensorio-motriz de niños/as (de 0 a 4 años) no videntes, a través de...
Evaluación buco-dental en niños de 0 a 3 años realizada en el control de salud del niño en consultorios y CESFAM : Región Metropolitana. Santiago-Chile
(Universidad de Chile, 2009)
Prevalencia de Caries Temprana de la Infancia
en niños de 0 a 3 años de edad ………………….. pág. 8
II.2 Atención Odontológica Temprana ………………….. pág. 11
II.3 Odontología Perinatal …………………………............. pág. 16
1. Educación y atención clínica de la...
con la atención temprana del niño, son algunas de las claves para dicho objetivo. Ello porque los padres son los que definen los hábitos alimentarios, de higiene oral y cuidados de salud del niño. Además permite que las intervenciones realizadas...
con la atención temprana del niño, son algunas de las claves para dicho objetivo. Ello porque los padres son los que definen los hábitos alimentarios, de higiene oral y cuidados de salud del niño. Además permite que las intervenciones realizadas...
Comparación del tiempo requerido para la atención odontológica de pacientes con discapacidad intelectual y pacientes sanos atendidos en la clínica odontológica de la Universidad de Chile
(Universidad de Chile, 2013)
enfermedad periodontal, lo que está relacionado con el desarrollo de
anomalías propias de la patología, la incapacidad por parte de la persona de
realizar un adecuado cuidado bucal y la falta de atención dental a una edad
temprana debido a otros problemas...
COMPARACIÓN DEL TIEMPO REQUERIDO PARA LA ATENCIÓN ODONTOLÓGICA DE PACIENTES CON DISCAPACIDAD INTELECTUAL Y PACIENTES SANOS ATENDIDOS EN LA CLÍNICA ODONTOLÓGICA DE LA UNIVERSIDAD DE CHILE...
COMPARACIÓN DEL TIEMPO REQUERIDO PARA LA ATENCIÓN ODONTOLÓGICA DE PACIENTES CON DISCAPACIDAD INTELECTUAL Y PACIENTES SANOS ATENDIDOS EN LA CLÍNICA ODONTOLÓGICA DE LA UNIVERSIDAD DE CHILE...
La fuerza del reflejo olivococlear medial se asocia con el rendimiento de las respuestas tardías en una tarea de discriminación visual con distractores sonoros ecológicos
(Universidad de Chile, 2022)
específicas en cuanto al control cognitivo sobre las respuestas tempranas a señales auditivas provenientes del exterior, por ejemplo, la supresión de información irrelevante mientras se destinan recursos cognitivos a otra modalidad sensorial. La implicancia...
Mammals have a neural network that originates in the auditory cortex and descends through different subcortical nuclei to reach the cochlear receptor. This network, called the efferent auditory system, has been attributed specific functions in terms of cognitive control over early responses to auditory signals from the outside, for example, the suppression of irrelevant information while cognitive resources are allocated to another sensory modality. The implication of the auditory efferent system in cognitive processing and behavioral performance remains a phenomenon open to discussion. In mice, rats and chinchillas there is evidence that strongly supports the functionality of the efferent auditory system in operant behavioral tasks of selective attention. Here we wonder if the auditory efferent system may be a biological filter for auditory responses involved in cognitive processes other than selective attention. We propose that the strength of the medial olivocochlear reflex correlates with late behavioral responses, emitted after a period of darkness of at least 2 seconds from the end of the target light, in a visual selective attention task in the presence of auditory distractors. Therefore, we investigated whether medial olivocochlear reflex strength is associated with behavioral performance of delayed responses during a selective visual attention paradigm in chinchillas. We found that the strength of the olivocochlear reflex, measured with contralateral noise and otoacoustic emissions, is associated with the animals' performance in delayed behavioral responses in the presence of ecologically relevant auditory distractors. These results suggest that the efferent auditory system may function as a biological filter for responses to auditory distractors in processes that occur seconds after the presentation of behaviorally relevant stimuli....
Mammals have a neural network that originates in the auditory cortex and descends through different subcortical nuclei to reach the cochlear receptor. This network, called the efferent auditory system, has been attributed specific functions in terms of cognitive control over early responses to auditory signals from the outside, for example, the suppression of irrelevant information while cognitive resources are allocated to another sensory modality. The implication of the auditory efferent system in cognitive processing and behavioral performance remains a phenomenon open to discussion. In mice, rats and chinchillas there is evidence that strongly supports the functionality of the efferent auditory system in operant behavioral tasks of selective attention. Here we wonder if the auditory efferent system may be a biological filter for auditory responses involved in cognitive processes other than selective attention. We propose that the strength of the medial olivocochlear reflex correlates with late behavioral responses, emitted after a period of darkness of at least 2 seconds from the end of the target light, in a visual selective attention task in the presence of auditory distractors. Therefore, we investigated whether medial olivocochlear reflex strength is associated with behavioral performance of delayed responses during a selective visual attention paradigm in chinchillas. We found that the strength of the olivocochlear reflex, measured with contralateral noise and otoacoustic emissions, is associated with the animals' performance in delayed behavioral responses in the presence of ecologically relevant auditory distractors. These results suggest that the efferent auditory system may function as a biological filter for responses to auditory distractors in processes that occur seconds after the presentation of behaviorally relevant stimuli....
Efectos de la estimulación temprana mediante el protocolo piloto madre-canguro en el peso del recién nacido prematuro y el estrés de su madre
(Universidad de Chile, 2011)
La estimulación temprana mediante el Método Canguro posee múltiples efectos, tanto en los recién nacidos prematuros como en sus padres, por lo que ha sido recomendada como intervención para promover el crecimiento y desarrollo de los neonatos desde...
Early stimulation using Kangaroo Method seems to have numerous effects on preterm infants as much as their parents. It has been promoted as intervention for growth and development of newborns from a comprehensive view. Hence, the objective of the study is to determine whether the application of the Kangaroo Mother Care Pilot Protocol, elaborated by the neonatology unit of Luís Tisné Hospital, generates changes on weight mother stress and adverse events on preterm infants. The research is a descriptive and non-experimental, longitudinal design. In which is analized a group of 11 preterm infants and their mothers, collecting data from: on newborns, the presence of adverse events during the technique and the quantification of mother´s stress level (Maternal Stress Scale). From the results of the study we found a variation of 20,81% ± 6,83 on the percentage of weight gain, on the 10 days before the aplication of the stimulation, and a 23,13% ± 3,66 variation on the 10 days after, with no significant differences (p=0,31) in conjuction with the absence of adverse events. Finally, the decrease on mother´s stress, register by the aplication of the Kangaroo Mother Care Protocol, displayed a reduction statistically significant on each dimension of the Stress Maternal Scale (p=0,000)....
Early stimulation using Kangaroo Method seems to have numerous effects on preterm infants as much as their parents. It has been promoted as intervention for growth and development of newborns from a comprehensive view. Hence, the objective of the study is to determine whether the application of the Kangaroo Mother Care Pilot Protocol, elaborated by the neonatology unit of Luís Tisné Hospital, generates changes on weight mother stress and adverse events on preterm infants. The research is a descriptive and non-experimental, longitudinal design. In which is analized a group of 11 preterm infants and their mothers, collecting data from: on newborns, the presence of adverse events during the technique and the quantification of mother´s stress level (Maternal Stress Scale). From the results of the study we found a variation of 20,81% ± 6,83 on the percentage of weight gain, on the 10 days before the aplication of the stimulation, and a 23,13% ± 3,66 variation on the 10 days after, with no significant differences (p=0,31) in conjuction with the absence of adverse events. Finally, the decrease on mother´s stress, register by the aplication of the Kangaroo Mother Care Protocol, displayed a reduction statistically significant on each dimension of the Stress Maternal Scale (p=0,000)....
Detección temprana de riesgo cardiovascular usando text mining en los campos de texto no estructurado del registro clínico electrónico
(Universidad de Chile, 2014)
trabajo se enfoca en modelos de prediccio´n para detectar de forma temprana el
riesgo cardiovascular, a partir de los datos del registro cl´ınico electro´nico de la atencio´n primaria de
salud pu´blica en Chile.
La importancia de trabajar en medidas...
necesario contar con sistemas que permitan la deteccio´n temprana de riesgo cardiovascular y/o que permitan apoyar la gestio´n del me´dico durante la atencio´n para poder aplicar medidas preventivas con tiempo suficiente, en caso de existir riesgo. El...
necesario contar con sistemas que permitan la deteccio´n temprana de riesgo cardiovascular y/o que permitan apoyar la gestio´n del me´dico durante la atencio´n para poder aplicar medidas preventivas con tiempo suficiente, en caso de existir riesgo. El...
Modelo predictivo de la demanda de atención de urgencia en Chile : una aplicación de Google Trends.
(Universidad de Chile, 2018)
recursos humanos y físicos (camas, boxes de atención, sala de procedimientos, equipamiento general, etc.) y de esta manera mejoraría el flujo de pacientes y del servicio en general. El uso de internet, cada vez más masivo, podría ser utilizado como...
Background: Overcrowding and extended waiting times of patients are common problems in Emergency Department (ED) in Chile and in the world. A forecasting model of demand, would allow a better planning and distribution of both human and material resources (beds, examination and procedure rooms, general equipment), improving the patients flow and service. The use of internet, every time more massive, could be used as a tool to predict the patient’s needs, limiting overcrowding and its problems, which would allow to take advantage of this tool to foresee the problems that generate overcrowding. Objective: Estimate if in Chile, search in Google could predict the number of patient´s visits for respiratory diseases in UEH or primary care (SAPU or SAR) ED. Methods: Retrospective analysis, evaluating the search behavior in Google related to respiratory diseases, with the amount of ED visits for those diseases. A time series analysis was performed using SARIMA and ARIMAX models, assessing the correlation grade between the two series and forecasting performance of ED “Visits” time series. Additionally a Granger causality test was used to evaluate if the two time series were related in the direction of the hypothesis or if it was a reverse causality case. Relevance: The use of spontaneous information of users could become a useful tool to anticipate overcrowding of patients with respiratory causes in ED in Chile, allowing the reorganization of human and material resources, improving the patient´s care. Results: The SARIMA (2, 0, 1)(2, 0, 0)[7] model, generated the best prediction (Mean Absolute Percentage Error (MAPE) 1,46% and 17,87% for the training and test groups, respectively) for time series “Visits”. Of a hundred searches found with google correlate, a 100% was directly or indirectly related to respiratory diseases, most of them regarding to treatment. The best fit of ARIMAX model was when the sum of the ten first searches was used as an exogenous variable, with a MAPE of 0,97% and 3,54% for the training and test groups, respectively. The Granger test showed bidirectional causality for the two time series analyzed. Conclusion: The use of Google searches allowed the design of a forecasting model for respiratory related patient´s visits to the ED in Chile. Based on the MAPE, the sum of the 10 first searches was chosen as the exogenous variable of the ARIMAX model. However, it is still necessary to evaluate this model under unusual frequency patterns of respiratory diseases, in order to study whether other factors could influence the results. Furthermore, it was not possible to determine whether patients performed the Google searches before or after visiting the ED, the impact of which needs to be clarified before implementation....
Background: Overcrowding and extended waiting times of patients are common problems in Emergency Department (ED) in Chile and in the world. A forecasting model of demand, would allow a better planning and distribution of both human and material resources (beds, examination and procedure rooms, general equipment), improving the patients flow and service. The use of internet, every time more massive, could be used as a tool to predict the patient’s needs, limiting overcrowding and its problems, which would allow to take advantage of this tool to foresee the problems that generate overcrowding. Objective: Estimate if in Chile, search in Google could predict the number of patient´s visits for respiratory diseases in UEH or primary care (SAPU or SAR) ED. Methods: Retrospective analysis, evaluating the search behavior in Google related to respiratory diseases, with the amount of ED visits for those diseases. A time series analysis was performed using SARIMA and ARIMAX models, assessing the correlation grade between the two series and forecasting performance of ED “Visits” time series. Additionally a Granger causality test was used to evaluate if the two time series were related in the direction of the hypothesis or if it was a reverse causality case. Relevance: The use of spontaneous information of users could become a useful tool to anticipate overcrowding of patients with respiratory causes in ED in Chile, allowing the reorganization of human and material resources, improving the patient´s care. Results: The SARIMA (2, 0, 1)(2, 0, 0)[7] model, generated the best prediction (Mean Absolute Percentage Error (MAPE) 1,46% and 17,87% for the training and test groups, respectively) for time series “Visits”. Of a hundred searches found with google correlate, a 100% was directly or indirectly related to respiratory diseases, most of them regarding to treatment. The best fit of ARIMAX model was when the sum of the ten first searches was used as an exogenous variable, with a MAPE of 0,97% and 3,54% for the training and test groups, respectively. The Granger test showed bidirectional causality for the two time series analyzed. Conclusion: The use of Google searches allowed the design of a forecasting model for respiratory related patient´s visits to the ED in Chile. Based on the MAPE, the sum of the 10 first searches was chosen as the exogenous variable of the ARIMAX model. However, it is still necessary to evaluate this model under unusual frequency patterns of respiratory diseases, in order to study whether other factors could influence the results. Furthermore, it was not possible to determine whether patients performed the Google searches before or after visiting the ED, the impact of which needs to be clarified before implementation....
Fitoestrógenos nutricionales como inductores de fenotipo epigenético en etapas tempranas del desarrollo en mamíferos
(Universidad de Chile, 2006)
La variación de caracteres entre individuos de una población es un tema central en la teoría
darwiniana de la Selección Natural, aún cuando los procesos involucrados en el origen de estas
variaciones han recibido menor atención. Desde una...
Variation in characters among individuals in a population is a central topic in the Darwinian theory of Natural Selectíon. Even more when the processes involved on the origin of such variations have received minor attention. From an evolutionary perspective, the origin of a specialization in a lineage may be treated as a different issue than of the maintenance of such specialization, once it is originated. In this sense, embryonic development would be the main responsible for the origin ofthe viable phenotypic variation and furthermore, capable to be selected. On the other hand, Natural Selection would then define which variant can prosper and perpetuate in evolution. Thus, it is possible to focus on the study of those processes leading to the origin of the heritable phenotypic variability without the need for knowing whether the novelties that eventually arise will be subjected to further selective processes. Nevertheless, to study the origin of the morphologic novelties and the restrictions on the phenotypic change it is required to know about the processes driving development. Epigenetic changes occurring during development have lead to significant morphological transformations along the evolutionary history. There are some evidenccs showing that environmental xenobiotics can interfere during early devclopment, which could have consequences on the adult stage. During the embryonic process, the microenvironment where the fetus develops is susceptible to influcnces from thc mother and therefore, also susceptible to changes in maternal hormonal state. Such hormonal state can be strongly influenced by thc cnvironment, through the action of compounds with estrogenic effects, Some of thosc compounds can be found in vegetables. These are called phytoestrogens, Somc phytoestrogens as daidzein and genistein can be naturally available for rodent consumption. It has been described in rodents that changes in the epigcnotype produccd after early cxposure to compounds with estrogenic action (CEA) can be transmitted to the subsequent generations. Such kind of heredity could be attributed to the action of such CEA on DNA methylation. In addition, there are evidcnces reporting that high amounts of dietary phytoestrogens are able to produce considerable cstrogenic activity, comparable to that produced by DES, and that early ontogcnctical cxposure to phytoestrogens can trigger morphologic alterations and on methylation pattcrns on proto-oncogenes, Based on that evidences, 1 proposed that in rodents, alterations in the hormonal state of pregnant females produced by the consumption of phytoestrogens (or other xenocstrogens) affect: i) the hormonal signaling in the intrauterinc environmcnt wherc embryo dcvelopmcnt takes place, which in turn have consequences on ii) the process of resetting of methylation patterns in the developing embryo, which produces alterations in both the resulting adult phenotype and in lifc history characters of a population. The present study evaluated in Mus musculus domesticus if natural CAEs (in the present case, dietary phytoestrogens), acting through the mother could be able to produce epigenetic modifications at early stages during development, verifying also the consequences on life-history parameters. The experimental approaeh to investigate it consisted of feeding adult rodents ad libitum with a diet high in phytoestrogens, containing 2% of a soy (Glycine max) isoflavones-extract. Soy is the food item presenting the higher known concentrations of the phytocstrogens genistcin and daidzein, It was cvaluated if such high maternal consumption of phytoestrogens could be producing ehanges in DNA methylation patterns in two specific gene s in the adult offspring, in liver and pancreas, or in general methylation along the genome in blastocysts. Morphomctric and life history characters were also evaluated in the offspring of mice couples subjected to control diet or the diet containing 2% isoflavone-extract. Previous evidence in Mus musculus shows that these traits are modified whcn subjecting neonatal rodents to treatment with phytoestrogens. Nevcrtheless, no studies have reported these effects on offspring from pregnant mothers fceding high amounts ofphytoestrogens. In thc present study, rodents werc assigned to one of the following experimental treatments: mice were fed ad libitum on i) control diet (chow diet for rodents), or on ii) control diet plus 2% soyisoflavones concentrate (ISF diet). The effect of the consumption of a diet high on phytoestrogens was assessed in an experimental population of mice. Threc levels of analysis were defined to evaluate the hypothesis. The experimental approach used in this thesis focused on: i) the physiological level on mothers, developing a technique capable of detecting and quantifying intrauterine catecholestrogens through HPLC, since secretion of these compounds could be affected by a high consumption of phytoestrogens; ii) the molecular level, measuring DNA methylation in thc offspring (blastocysts and adults) of mothers consuming high amounts of phytoestrogens, on genes o-Actin and Estrogen Receptor-a in adults and UNE repeated sequence in blastocysts; iii) the ecological level in the adult offspring, measuring morphometric and life-hístory characters, such as weight, size, ano-genital distance and timing of sexual maturation, in the offspring of mice couples subjected to control or ISF diet. With regard to the experimental results, in the ecological level important changes were detected in the offspring in response to the phytoestrogenic treatment, among them, reduction in size of adult males (morphometric parameter) and advancement of sexual maturation in females (life-history parameter). At the molecular level, changes in methylation in CpG sites were observed in the offspring in response to the phytoestrogenic trcatmcnt. Changes were detected in adults for ce-Actin gene in liver and páncreas, and for ER~ gene in liver. In addition, reduced mutations were observed in two CpG sites in UNE repeated sequcnce in blastocysts from mothers eonsuming high quantities ofphytoestrogens. Thus, environmental agents as phytocstrogens, acting in key stages during ontogeny are able to induce important alterations as: i) on epigenetic paramcters as gene specific DNA methylation, ii) on life-history characters that influences population structure, as timing of sexual maturation, and iii) on morphometric parameters sueh as adult weight, whieh may represent either an epigenetie effeet associated to Imprinted Genes, or to a physiological effect related to mimicking of hormonal stimuli by phytoestrogens. These results highlight the importance of giving more emphasis to inductive evolutionary processes in addition to restrictive evolutionary processes. This focus emphasises how evolutionary changes may arise as structural organismic responses to specific environmental stimuli, which can in tum act in very limited windows of time during ontogeny, making possible such a response. Nevertheless, the former do not exc1ude the possibility that such environmentally induced changes may be further transformed in adaptations. In parallel, such focus reinforce that the study of adaptations and/or natural selection is not a requirement for studying evolution. It is undcniable that the way in which the environment restricts the organism structure is fundamental for the shaping of it. Neverthcless, as important is how the environment induces changes that help to shape the organismo Such a mechanism should be more considered in studies of evolutionary biology...
Variation in characters among individuals in a population is a central topic in the Darwinian theory of Natural Selectíon. Even more when the processes involved on the origin of such variations have received minor attention. From an evolutionary perspective, the origin of a specialization in a lineage may be treated as a different issue than of the maintenance of such specialization, once it is originated. In this sense, embryonic development would be the main responsible for the origin ofthe viable phenotypic variation and furthermore, capable to be selected. On the other hand, Natural Selection would then define which variant can prosper and perpetuate in evolution. Thus, it is possible to focus on the study of those processes leading to the origin of the heritable phenotypic variability without the need for knowing whether the novelties that eventually arise will be subjected to further selective processes. Nevertheless, to study the origin of the morphologic novelties and the restrictions on the phenotypic change it is required to know about the processes driving development. Epigenetic changes occurring during development have lead to significant morphological transformations along the evolutionary history. There are some evidenccs showing that environmental xenobiotics can interfere during early devclopment, which could have consequences on the adult stage. During the embryonic process, the microenvironment where the fetus develops is susceptible to influcnces from thc mother and therefore, also susceptible to changes in maternal hormonal state. Such hormonal state can be strongly influenced by thc cnvironment, through the action of compounds with estrogenic effects, Some of thosc compounds can be found in vegetables. These are called phytoestrogens, Somc phytoestrogens as daidzein and genistein can be naturally available for rodent consumption. It has been described in rodents that changes in the epigcnotype produccd after early cxposure to compounds with estrogenic action (CEA) can be transmitted to the subsequent generations. Such kind of heredity could be attributed to the action of such CEA on DNA methylation. In addition, there are evidcnces reporting that high amounts of dietary phytoestrogens are able to produce considerable cstrogenic activity, comparable to that produced by DES, and that early ontogcnctical cxposure to phytoestrogens can trigger morphologic alterations and on methylation pattcrns on proto-oncogenes, Based on that evidences, 1 proposed that in rodents, alterations in the hormonal state of pregnant females produced by the consumption of phytoestrogens (or other xenocstrogens) affect: i) the hormonal signaling in the intrauterinc environmcnt wherc embryo dcvelopmcnt takes place, which in turn have consequences on ii) the process of resetting of methylation patterns in the developing embryo, which produces alterations in both the resulting adult phenotype and in lifc history characters of a population. The present study evaluated in Mus musculus domesticus if natural CAEs (in the present case, dietary phytoestrogens), acting through the mother could be able to produce epigenetic modifications at early stages during development, verifying also the consequences on life-history parameters. The experimental approaeh to investigate it consisted of feeding adult rodents ad libitum with a diet high in phytoestrogens, containing 2% of a soy (Glycine max) isoflavones-extract. Soy is the food item presenting the higher known concentrations of the phytocstrogens genistcin and daidzein, It was cvaluated if such high maternal consumption of phytoestrogens could be producing ehanges in DNA methylation patterns in two specific gene s in the adult offspring, in liver and pancreas, or in general methylation along the genome in blastocysts. Morphomctric and life history characters were also evaluated in the offspring of mice couples subjected to control diet or the diet containing 2% isoflavone-extract. Previous evidence in Mus musculus shows that these traits are modified whcn subjecting neonatal rodents to treatment with phytoestrogens. Nevcrtheless, no studies have reported these effects on offspring from pregnant mothers fceding high amounts ofphytoestrogens. In thc present study, rodents werc assigned to one of the following experimental treatments: mice were fed ad libitum on i) control diet (chow diet for rodents), or on ii) control diet plus 2% soyisoflavones concentrate (ISF diet). The effect of the consumption of a diet high on phytoestrogens was assessed in an experimental population of mice. Threc levels of analysis were defined to evaluate the hypothesis. The experimental approach used in this thesis focused on: i) the physiological level on mothers, developing a technique capable of detecting and quantifying intrauterine catecholestrogens through HPLC, since secretion of these compounds could be affected by a high consumption of phytoestrogens; ii) the molecular level, measuring DNA methylation in thc offspring (blastocysts and adults) of mothers consuming high amounts of phytoestrogens, on genes o-Actin and Estrogen Receptor-a in adults and UNE repeated sequence in blastocysts; iii) the ecological level in the adult offspring, measuring morphometric and life-hístory characters, such as weight, size, ano-genital distance and timing of sexual maturation, in the offspring of mice couples subjected to control or ISF diet. With regard to the experimental results, in the ecological level important changes were detected in the offspring in response to the phytoestrogenic treatment, among them, reduction in size of adult males (morphometric parameter) and advancement of sexual maturation in females (life-history parameter). At the molecular level, changes in methylation in CpG sites were observed in the offspring in response to the phytoestrogenic trcatmcnt. Changes were detected in adults for ce-Actin gene in liver and páncreas, and for ER~ gene in liver. In addition, reduced mutations were observed in two CpG sites in UNE repeated sequcnce in blastocysts from mothers eonsuming high quantities ofphytoestrogens. Thus, environmental agents as phytocstrogens, acting in key stages during ontogeny are able to induce important alterations as: i) on epigenetic paramcters as gene specific DNA methylation, ii) on life-history characters that influences population structure, as timing of sexual maturation, and iii) on morphometric parameters sueh as adult weight, whieh may represent either an epigenetie effeet associated to Imprinted Genes, or to a physiological effect related to mimicking of hormonal stimuli by phytoestrogens. These results highlight the importance of giving more emphasis to inductive evolutionary processes in addition to restrictive evolutionary processes. This focus emphasises how evolutionary changes may arise as structural organismic responses to specific environmental stimuli, which can in tum act in very limited windows of time during ontogeny, making possible such a response. Nevertheless, the former do not exc1ude the possibility that such environmentally induced changes may be further transformed in adaptations. In parallel, such focus reinforce that the study of adaptations and/or natural selection is not a requirement for studying evolution. It is undcniable that the way in which the environment restricts the organism structure is fundamental for the shaping of it. Neverthcless, as important is how the environment induces changes that help to shape the organismo Such a mechanism should be more considered in studies of evolutionary biology...