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La prévalence de l'obésité et le sédentarisme chez les adolescents augmentate de manière significative dans le monde entier. La chaleur de l'environnement est une préoccupation supplémentaire au moment de recommander la pratique du sport chez les adolescents obèses et sédentaires. Les risques liés á l’augmentation de la température centrale du corps sont á considérer. L’augmentation de température est un facteur aggravant qui augmente de la perception de l'effort (IPE), l’irritabilité, et modifie les sensations liées au confort thermique. Il existe peu d'études ayant evalué les réponses de thermorégulation et la perception des filles pratiquant l'exercice dans la chaleur, en particulier chez les filles obèses. Par conséquent, il est utile d’apporter plus de précisions sur l'impact de l'obésité associée ou non à un mode de vie sédentaire pendant les activités sportives dans la chaleur. Le but de cette étude était de déterminer et comparer la thermorégulation et les réponses perceptives des filles pubères obèses et de poids normal avec un profil de forme cardiorespiratoire élevé (fit) et faible (unfit) avant, pendant et après deux séances d'entraînement dans la chaleur. Ceci a été réalisé au cours d’ une étude transversale dans laquelle 34 filles: 21 obèses (12 fit et 9 unfit) et 13 de poids normal (5 fit et 8 unfit) ont pédalé pendant 50 minutes sur un ergomètre à 36oC et 40% HR à l'intérieur une chambre environnementale. Deux séances d'exercice avec des intensités d’efforts différentes ont été réalisées. Dans la première session l'objectif a été fixé á 45% du VO2pic (Sèance % VO2pic) et dans la seconde á 4,5 W.kg-1 (Sèance PCM). Pendant les séances d'exercice, la température rectale (Tre), la température de la peau (IPEau), la fréquence cardiaque (FC), IPE, l’ irritabilité, et les sensations thermique et de confort thermique ont été recueillies. Aucune différence n'a été identifiée entre les groupes tout au long de la séance d'exercice et de récupération pour les variables de thermorégulation, perception et transpiration dans les deux conditions d’effort testées. Les résultats de ce travail montrent que indépendamment de la capacité cardiorespiratoire, dans les conditions d'exercice et le stress thermique de 36oC et 40% d'humidité relative, les filles pubères obèses ou non ont des réponses de thermorégulation et perception similaires lors de l'exercice effectué au cours d’ un ergocycle réalisé á températures élevées. A prevalência da obesidade e do sedentarismo entre os adolescentes vem aumentando mundialmente de forma significativa. Acredita-se que o calor ambiental é uma preocupação adicional ao recomendar a prática esportiva em adolescentes obesos e sedentários, pois além dos riscos de aumento da temperatura corporal central, representa um agravante no aumento da percepção ao esforço (IPE), da irritabilidade, da sensação térmica e do conforto térmico. Ainda são poucos os estudos que avaliaram respostas termorregulatórias e perceptivas de meninas que realizaram exercícios no calor, especialmente de meninas obesas. Portanto, são necessários mais esclarecimentos das repercussões da obesidade combinada ou não com o sedentarismo durante a prática de atividades esportivas no calor. O objetivo deste estudo foi determinar e comparar as respostas termorregulatórias e perceptivas de meninas púberes obesas e eutróficas com alta (fit) e baixa (unfit) aptidão cardiorrespiratória antes, durante e após duas sessões de exercício no calor. Trata-se de um estudo de caráter transversal em que 34 meninas: 21 obesas (12 fit e 9 unfit) e 13 eutróficas (5 fit e 8 unfit) pedalaram durante 50 minutos em cicloergômetro no calor (36oC e 40% de umidade relativa do ar) dentro de uma câmara ambiental. Foram realizadas duas sessões de exercício com metas de intensidade diferentes. Na primeira sessão, fixou-se a meta de intensidade em 45% do pico de Volume de O2 (Sessão %VO2pico) e na segunda, em 4,5 W.kg-1 (Sessão PCM). Durante as sessões de exercício, foram coletadas temperatura retal (Tre), temperatura de pele (Tpele), frequência cardíaca (FC), IPE, irritabilidade, sensação térmica e conforto térmico. Não foram identificadas diferenças entre os grupos ao longo da sessão de exercício e recuperação para as variáveis termorregulatórias, perceptivas e de sudorese quando meninas obesas e eutróficas fit e unfit pedalaram em cicloergômetro a 45% do VO2pico ou a 4,5 W.kg-1 durante 50 minutos em câmara ambiental. Assim, conclui-se que independente do estado nutricional ou aptidão cardiorrespiratória, sob as condições de exercício e estresse térmico de 36oC e 40% UR, meninas púberes apresentam respostas termorregulatórias e perceptivas semelhantes quando submetidas a uma sessão de exercício em cicloergômetro no calor. Obesity prevalence and sedentary behavior among teenagers is increasing significantly worldwide. It is believed that the heat stress is an additional concern when recommending the practice of sports to obese and sedentary adolescents. In addition, the risks of increasing core body temperature is an aggravating factor to the increase in the perceived exertion (RPE) irritability, thermal sensation and thermal comfort. Few studies have evaluated thermoregulatory and perceptual responses in girls who underwent exercise in the heat, especially in obese girls. Therefore, further understanding of the impact of obesity combined or not with sedentary behavior during sport activities under heat stress is still required. The aim of this study was to determine and to compare the thermoregulatory and perceptual responses of obese and eutrophic pubescent girls with high (fit) and low (unfit) cardiorespiratory capacity, before,during and after two workouts under heat stress. This is a transversal study including 34 girls, in which 21 obese (12 fit and 9 unfit) and 13 eutrophic (5 fit and 8 unfit) cycled for 50 min on a cycle ergometer under heat stress (36oC and 40% RH), inside an environmental chamber. Two exercise sessions with different intensity targets were performed. In the first session, the intensity target was set at 45% of the VO2peak (% VO2peak Session), and the second was set at 4.5 W.kg-1 (MHP Session). During the exercise sessions, rectal temperature (Tre), skin temperature (Tskin), heart rate (HR) RPE, irritability, thermal sensation, and thermal comfort were collected. No differences were detected between groups throughout the exercise and during the recovery session for thermoregulatory, perceptive and sweat variables when obese and eutrophic fit and unfit girls exercised on a cycle ergometer at 45% of VO2peak or 4.5 W.kg-1 for 50 min in an environmental chamber. Therefore, it is concluded that, regardless the nutritional status or cardiorespiratory capacity, under the conditions of exercise and heat stress of 36oC and 40% RH, pubescent girls have similar thermoregulatory and perceptual responses when exercising on a cycle ergometer in the heat.

Testou-se a hipótese de que animais bem alimentados durante a vida fetal e durante o período pós-parto apresentariam melhor desempenho reprodutivo que aqueles com alimentação restrita durante a vida fetal e/ou no pós-parto, sendo animais com menor idade à puberdade. Utilizaram-se 120 ovelhas Merino Australiano prenhes com 60 dias de gestação, distribuídas em fatorial 2x2, com quatro níveis nutricionais, tendo metade de seus grupos invertidos. Os animais foram pesados no nascimento, e as ovelhas que pariram fêmeas foram eliminadas e os machos identificados por brincos de cores diferentes (laranja, roxo, preto e verde) e distribuídos entre os tratamentos. O escore corporal manteve as mesmas relações observadas para o peso corporal entre os grupos. Os animais de brinco preto apresentaram menor perímetro escrotal aos 132 dias, com maior crescimento escrotal, decorrente da melhora nutricional desses animais em determinados períodos. Como condição de escore corporal, o perímetro escrotal manteve a mesma relação entre os grupos, como observado para o peso corporal, com o grupo laranja com maior perímetro, seguido pelo grupo roxo, pelo verde e pelo preto. Apenas 62,5% dos animais manifestaram puberdade até o final do experimento. Os animais atingiram a puberdade com escore, com perímetro e com idade semelhantes, entretanto tiveram pesos diferentesThe hypothesis that animals well fed during the fetal life and in the post parturition would present better reproductive performance than those with restricted feeding, during the fetal life and/or in the post parturition was experimented pointing out that younger animals reach puberty first. One hundred and twenty pregnant Australian Merino sheep were used on the 60th day of gestation, distributed in a 2x2 factorial, with four nutritional levels, half of groups being were inverted. Birth weights were recorded. The females were eliminated and the males were identified by using earrings of different colors (orange, purple, black and green) distributed among the treatments. Body score maintained the same relations that were observed on body weight. Animals with black earring presented smaller scrotal perimeter on the 132nd day, with larger scrotal growth, due to the nutritional improvement of those animals on specific periods. As a condition of corporal score, the scrotal perimeter maintained the same relationship among the groups observed for the body weight: the orange group presented the highest perimeter, followed by the purple, green and black group. Only 62.5% of the animals reached puberty until the end of the experiment. Animals reached puberty with the same score, scrotal perimeter and age, albirt they presented different weights

Made available in DSpace on 2014-08-20T14:38:04Z (GMT). No. of bitstreams: 1 tese_fabiana_moreira.pdf: 1442913 bytes, checksum: 613ed46b361d675bfb046a7b74462171 (MD5) Previous issue date: 2011-11-22 Leptin is a multifunctional peptidic hormone, primarily produced by the adipose tissue, which has receptors (Ob-Rs) in reproductive organs, hypothalamus and hypophysis, acting in the appetite regulation and energetic expenditure, potentially influencing the expression of the reproductive function, at puberty and lactation. Reproductive failure are the main causes for female culling, representing 30% to 40%,of the total female culling. Thus, post-mortem evaluation of the genital organs at slaughter may have an important diagnostic value, helping on the identification of the stage of female`s estrous cycle and aiding the interpretation of reproductive abnormalities. Its long form receptor (OBR-b) performs signal transduction in several cell types via mitogen- activated protein kinases (MAPK) cascade, such as ERK 1/2 and p38. The first stage of this thesis is aimed to evaluate the presence of leptin and MPAK in oocites of pubertal sows and prepubertal gilts. Ovaries from 10 pubertal sows and 10 prepubertal gilts were collected at a slaughterhouse. Slides were analyzed for the presence of oocites included in primordial/primary (OIPF), secondary (OISF) and tertiary follicles (OITF). Immunohistochemistry (IHC) was performed with polyclonal antibodies anti-leptin and anti-phospho-MAPK (ERK 1/2 and p38). The second stage involved 28 pubertal sows and the analyses were performed in hypothalamic neurons, endometrial glands and oocytes. For IHC, the antibodies were polyclonal anti-leptin and anti-leptin receptor. Responses were compared with reproductive data registered for each female. All images in both stages were analyzed by 16-Bit Histogram application from Image J® software. Immunolabeling for leptin and activated ERK 1/2 MAPK were more intense in sows oocytes (p ≤ 0.05), while the immunolabeling for activated p38 MAPK was more intense in gilts oocytes (p = 0.05). In sows, OIPF were more intensely marked for leptin and p38 MAPK (p

Se evaluó la precisión y exactitud en la estimación de la grasa corporal (%) por absorciometría dual de rayos X (DXA Lunar-DPX-MD) comparado con el modelo de cuatro compartimentos (4C) en 32 púberes (F=16) de 9 a 14 años. El sesgo entre la DXA y el modelo de 4C fue de -3.5% de grasa (r=0.25; p=0.171) con un intervalo de confianza de -1.9 a -5.1 (p=0.050). Los límites de concordancia al 95% fueron de +5% a -12% de grasa. El coeficiente de correlación de concordancia fue de pc=0.85. La prueba de exactitud por análisis de regresión mostró que el intercepto y la pendiente de las estimaciones de grasa corporal por DXA fueron diferentes al modelo de 4C (p>0.05). La precisión evaluada con el valor de R2 mostró que la DXA explicó el 83% de la varianza de la grasa corporal por el modelo de 4C con un error de 4.1%. El error total como medida de exactitud fue de 5.6%. La exactitud grupal evaluada por análisis de varianza no mostró interacción entre el método (DXA-4C) y el análisis por separado del sexo, el estado puberal y la presencia de sobrepeso. No obstante, hubo efecto del método (p=0.043) en presencia de sobrepeso (p

Objetivo: obtener la validez y consistencia interna de un cuestionario para púberes mexicanos, hombres y mujeres, que evalúe factores de riesgo asociados a trastornos de la conducta alimentaria. Sujetos y método: El cuestionario se aplicó a una muestra no probabilística, de púberes estudiantes de la ciudad de México (504 hombres y 511 mujeres), con edades de 11 a 15 años de edad, con una media de 12,13. Se realizó un análisis de consistencia interna (alfa de Cronbach) y un análisis factorial de componentes principales con rotación oblimin por el método de máxima verosimilitud. Resultados: Ambos instrumentos arrojaron 5 factores, con una buena consistencia interna, alcanzando un valor total de alpha de Cronbach de 0,75 para hombres (55,6% de varianza explicada) y 0,83 para mujeres (57,6% de varianza explicada). Conclusión: El instrumento resultó válido en hombres y mujeres, para medir factores de riesgo asociados a trastornos alimentarios, principalmente socioculturales, conductas alimentarias y desarrollo puberal. Objective: To obtain the validity and internal consistency of a questionnaire for the screening of risk factors associated to eating disorders in Mexican pubescent males and females. Subjects and methods: The questionnaire was applied to a non-probabilistic sample of 504 males and 511 female students in México City from 11 to 15 years of age with a median of 12,13. Statistical methods included internal consistency analysis (Cronbach's alpha) and principal components factor analysis with oblimin rotation. Results: Both instruments obtained five-factors structure, showed a good total Cronbach's alpha score: males 0,75 (55,6 %), and females 0,83 (57,6%) of the total explained variance. Males displayed a normal eating behavior factor, while for females a restrictive dieting factor was obtained. Conclusions: This questionnaire is a valid measure in pubescent boys and girls for assessing risk factors associated with eating disorders, in particular socio-cultural factors, eating behaviors and pubertal development.

Objetivo: obtener la validez y consistencia interna de un cuestionario para púberes mexicanos, hombres y mujeres, que evalúe factores de riesgo asociados a trastornos de la conducta alimentaria. Sujetos y método: El cuestionario se aplicó a una muestra no probabilística, de púberes estudiantes de la ciudad de México (504 hombres y 511 mujeres), con edades de 11 a 15 años de edad, con una media de 12,13. Se realizó un análisis de consistencia interna (alfa de Cronbach) y un análisis factorial de componentes principales con rotación oblimin por el método de máxima verosimilitud. Resultados: Ambos instrumentos arrojaron 5 factores, con una buena consistencia interna, alcanzando un valor total de alpha de Cronbach de 0,75 para hombres (55,6% de varianza explicada) y 0,83 para mujeres (57,6% de varianza explicada). Conclusión: El instrumento resultó válido en hombres y mujeres, para medir factores de riesgo asociados a trastornos alimentarios, principalmente socioculturales, conductas alimentarias y desarrollo puberal.

The hypothesis that animals well fed during the fetal life and in the post parturition would present better reproductive performance than those with restricted feeding, during the fetal life and/or in the post parturition was experimented pointing out that younger animals reach puberty first. One hundred and twenty pregnant Australian Merino sheep were used on the 60th day of gestation, distributed in a 2x2 factorial, with four nutritional levels, half of groups being were inverted. Birth weights were recorded. The females were eliminated and the males were identified by using earrings of different colors (orange, purple, black and green) distributed among the treatments. Body score maintained the same relations that were observed on body weight. Animals with black earring presented smaller scrotal perimeter on the 132nd day, with larger scrotal growth, due to the nutritional improvement of those animals on specific periods. As a condition of corporal score, the scrotal perimeter maintained the same relationship among the groups observed for the body weight: the orange group presented the highest perimeter, followed by the purple, green and black group. Only 62.5% of the animals reached puberty until the end of the experiment. Animals reached puberty with the same score, scrotal perimeter and age, albirt they presented different weights Testou-se a hipótese de que animais bem alimentados durante a vida fetal e durante o período pós-parto apresentariam melhor desempenho reprodutivo que aqueles com alimentação restrita durante a vida fetal e/ou no pós-parto, sendo animais com menor idade à puberdade. Utilizaram-se 120 ovelhas Merino Australiano prenhes com 60 dias de gestação, distribuídas em fatorial 2x2, com quatro níveis nutricionais, tendo metade de seus grupos invertidos. Os animais foram pesados no nascimento, e as ovelhas que pariram fêmeas foram eliminadas e os machos identificados por brincos de cores diferentes (laranja, roxo, preto e verde) e distribuídos entre os tratamentos. O escore corporal manteve as mesmas relações observadas para o peso corporal entre os grupos. Os animais de brinco preto apresentaram menor perímetro escrotal aos 132 dias, com maior crescimento escrotal, decorrente da melhora nutricional desses animais em determinados períodos. Como condição de escore corporal, o perímetro escrotal manteve a mesma relação entre os grupos, como observado para o peso corporal, com o grupo laranja com maior perímetro, seguido pelo grupo roxo, pelo verde e pelo preto. Apenas 62,5% dos animais manifestaram puberdade até o final do experimento. Os animais atingiram a puberdade com escore, com perímetro e com idade semelhantes, entretanto tiveram pesos diferentes