In an attempt to understand girls' involvement conduct problems, this dissertation first reviews two existing theoretical approaches that provide an explanation for the development of conduct problems. Specifically, the available literature on the development and correlates of conduct problems in boys suggests the subtypes of conduct disorder represent two developmental trajectories. The adolescent-onset pathway is associated with deviant peers and few characterological problems, where as the childhood-onset pathway is associated with emotion regulation deficits, negative parenting, callous and unemotional traits, and neurological deficits. Research also suggests a gender-specific model, the delayed-onset model, for the development of conduct problems in girls. Following this theoretical review, differential predictions made by the competing theoretical models are tested in a community sample of school-aged girls and boys. Participants were 202 children (87 males and 115 females) in grades 5-9. The students ranged in age from 10 to 17 years old (M = 13.16). Similar to the total student body, the ethnic breakdown of the sample was as follows: African-American (60%), Caucasian (24%), Hispanic (6%), and Other (5%). Data was also collected from the students' parents and teachers. Results indicated that girls conduct problems did not follow either model in a consistent manner. Specifically, adolescent-onset conduct problem girls, childhood-onset conduct problem boys, and adolescentonset conduct problem boys differed from non-conduct problem children but did not differ significantly amongst themselves on study variables (e.g., deviant peer association, hyperactivity/impulsivity, emotional dysregulation, callous/unemotional traits). However, results suggest that gender-specific risk factors should be taken into account when developing theoretical models for girls' conduct problems. For example, early pubertal maturation is a particularly salient risk factor for conduct problems in girls, and pubertal development interacts with emotion regulation problems to place girls at high risk for deviant behavior. Finally, implications for prevention and intervention as well as future research are discussed.

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 <0.05), on the other hand, for gilts there was no difference in the marking of follicular oocytes from the analyzed categories. Hypothalamic neurons were more intensely marked in the sows culled by reproductive problems (p <0.05). The hypothalamus, uterus and oocytes of luteal or follicular phase sows showed more intense immunolabeling for leptin and OBR-b than the females with cystic ovaries. The immunolabeling for leptin was more pronounced in the hypothalamus and uterus of sows from parity order 2 group (PO 2-4) (p <0.05). These results demonstrate that leptin may be a marker for oocyte competence. Also, cyclic females having PO 2-4 presented more intense leptin immunolabeling in the hypothalamus and uterus and for OBR-b in the oocyte and uterus. The OBR-b immunolabeling was more pronounced in primiparous and multiparous females than for nulliparous. Therefore, immunolabeling for leptin and OBR-b can be a marker for reproductive performance in swine females. / A leptina é um hormônio peptídico multifuncional, produzido primariamente pelo tecido adiposo, com receptores (Ob-Rs) presentes em órgãos reprodutivos, hipotálamo e hipófise, que atua na regulação do apetite e no gasto energético, com potencial influência sobre a expressão da função reprodutiva, na puberdade e após a lactação. Desordens reprodutivas são as causas mais comuns, atribuídas ao total dos descartes, entre 30 e 40%. Considerando a alta proporção de descartes por estes problemas, a avaliação dos órgãos genitais no abate tem importante valor diagnóstico, auxiliando na identificação do estágio do ciclo estral da fêmea e na interpretação de possíveis anormalidades reprodutivas. O seu receptor de forma longa (OBR-b) realiza transdução de sinal em diversos tipos celulares via cascata das proteínas quinases ativadas por mitógenos (MAPK), tais como ERK 1/2 e p38. A primeira etapa do trabalho teve por objetivo avaliar a presença da leptina, e das MAPK nos oócitos de fêmeas suínas púberes e pré-púberes. Envolveu ovários de 10 fêmeas pré-púberes e 10 púberes coletados no abate e lâminas foram analisadas de oócitos inclusos em folículos primordiais/primários (OIFP), secundários (OIFS) e terciários (OIFT). Para a técnica de imuno-histoquímica (IHQ) os anticorpos policlonais instilados foram anti-leptina, anti-phospho- MAPK (ERK 1/2 e p38). A segunda etapa envolveu 28 porcas púberes descartadas, das quais foram analisados os neurônios do hipotálamo, glândulas endometriais e oócitos. Para a IHQ foram utilizados anticorpos policlonais anti-leptina e anti-receptor da leptina e objetivou comparar as respostas com os dados produtivos e reprodutivos a partir do registro de cada fêmea. Em ambas as etapas de trabalho foram utilizadas as modas obtidas pelo aplicativo 16 Bit-Histograma do software Image J®. A imunomarcação da leptina e a presença de ERK 1/2 ativada MAPK foram mais intensas em oócitos de porcas (p≤0,05), enquanto que a marcação para p38 MAPK ativada foi mais intensa em oócitos de leitoas (p=0,05). Em porcas, os OIFP estavam mais intensamente marcados para a leptina e p38 MAPK (p<0,05), mas para leitoas não foi observada diferença na marcação dos oócitos independente do estádio folicular. No hipotálamo a imunomarcação para a leptina foi mais intensa nas porcas descartadas por problemas reprodutivos (p<0,05). O hipotálamo, útero e oócitos das porcas que estavam na fase lútea ou fase folicular apresentaram imunomarcação para leptina e OBR-b mais acentuada que naquelas que possuíam cistos ovarianos. A imunomarcação para a leptina foi mais acentuada no hipotálamo e útero daquelas porcas do grupo ordem de parto 2 (OP 2-4) (p<0,05). Estes resultados demonstram que a leptina pode ser um dos marcadores para competência oocitária. Além disso, pode também ser observado que fêmeas cíclicas com OP 2-4 partos apresentam imunomarcação mais intensa para leptina no hipotálamo e útero, e OBR-b nos oócitos e útero. O OBR-b obteve marcação mais acentuada em fêmeas primíparas e multíparas, que nulíparas. Portanto, a imunomarcação para leptina e OBR-b podem ser um marcador de sinalização reprodutivo em fêmeas suínas.

<p>This thesis outlined a novel operationalization and extension of the thrifty phenotype and fetal overnutrition hypotheses, two evolutionary developmental hypotheses stemming from the developmental origins of health and disease perspective, for developmental pathways from prenatal risk through child growth to early puberty. Support has accumulated for both, but previous studies have not clearly determined which hypothesis better predicts early puberty. Using the Fragile Families and Child Wellbeing Study (<i>n</i>=4898), the thrifty phenotype and fetal overnutrition pathways were tested against each other, separately by sex, and race/ethnicity for adrenal, and gonadal pubertal markers. Results indicated that in general, both hypotheses were supported. Contrary to hypotheses, the thrifty phenotype pathway did not predict perceived pubertal timing better in boys and the fetal overnutrition pathway did not predict perceived pubertal timing best in girls. Instead, both pathways predicted puberty equally well between girls and boys and the fetal overnutrition pathway stemming from maternal gestational weight gain was stronger than the pre-pregnancy BMI pathway. Individual paths of the hypothesized pathways were generally supported when analyzed by race/ethnicity group separately, but support for the entire pathways were sparse. Implications of this work are that pubertal timing may be similarly programmed by restrictive and overnutrition prenatal risks, both should be prioritized, and that interventions for maternal gestational weight should be prioritized over interventions for pre-pregnancy BMI for reducing rates of early puberty. </p>

Osteoporosis, a major public health problem, likely has its origins in childhood. During periods of rapid skeletal growth, diet may influence accrual of bone mineral density (BMD) and adult bone health. This study used novel approaches in bone imaging to further characterize optimal skeletal development and enhance our understanding of key dietary components that influence attainment of peak bone mass (PBM) and contribute to determinants of peak bone strength in peri-pubertal females. The use of a validated food-frequency questionnaire (FFQ) enabled the influence of usual dietary intake on bone parameters to be examined.This study examined the relationship of dietary intake of micronutrients and bone macro-architectural structure in peri-pubertal girls. This study suggested that vitamin C and zinc intake are associated with objective measures of bone status in 4th, but not 6th grade girls. This indicates potential differences in micronutrient and bone associations at various age-associated stages of bone maturation.The impact of dietary fat on peri-pubertal skeletal growth is not well characterized. This study examined relationships of select dietary fatty acid (FA) intakes and measures of bone status in peri-pubertal girls. This study suggested that MUFA, total PUFA, n-6 and linoleic acid (LA) are inversely associated with bone status prior to menarche, but composition of dietary fat may be more important during the early-pubertal years. Decreased intakes of n-6 PUFA may benefit bone health in young girls.The impact of a dietary protein on volumetric bone mineral density (vBMD), bone mineral content (BMC) and bone strength throughout maturation remains controversial. Given evidence of both anabolic and catabolic affects of protein on bone health, this study examined relations of dietary protein from different sources with bone parameters in peri-pubertal girls. This study showed that dietary protein intake is related to higher trabecular but not cortical vBMD, BMC and BSI, and accounts for 2-4% of their variability in peri-pubertal girls. The relationship seems to vary by the source of dietary protein and calcium intake. However, a negative impact of animal protein on bone health is not supported. Large scale observational and intervention studies are needed to establish causality.

A crescente prevalência de diabetes mellitus (DM) em nível mundial, a sua incidência cada vez maior em crianças e adolescentes e resultados prévios obtidos em nosso laboratório (piora do quadro diabético em ratos na puberdade) nos levaram a investigar o metabolismo de glicose em tecido adiposo branco na puberdade em ratos controle (CO) e intolerantes à glicose (STZ). Parâmetros de desenvolvimento corporal e maturação sexual foram estudados entre a 5ª e a 10ª semanas de vida dos animais, identificando-se a 6ª e 7ª semanas como importante fase da puberdade. Desta forma, os estudos metabólicos foram realizados neste período. Os animais CO apresentaram franca resistência à insulina no período da puberdade, com prejuízos no metabolismo de glicose em adipócitos isolados. A injeção de estreptozotocina no quinto dia de vida produziu um quadro de intolerância à glicose em nossos animais, resultando em atraso no início do estirão de crescimento e desenvolvimento sexual. A resistência fisiológica à insulina da puberdade não produziu piora da resposta à insulina no tecido adiposo branco. / The growth in the prevalence of diabetes mellitus (DM), a larger incidence of type 1 and 2 DM in children and adolescents and the previous results of our laboratory (worsening of the metabolic picture in diabetic rats during puberty) motivate us to study the glucose metabolism in the puberty in order to assess the possible influence of the physiological insulin resistance characteristic of this period on the course of the diabetic status. Five-day old male Wistar rats were divided into two experimental groups: control group (CO) and streptozotocin group (STZ). Body development and sexual maturation were weekly evaluated between the 5th and 10th weeks of life. We identify the 6th and 7th weeks as an important early phase of the puberty. The insulin resistance and a slight degree of glucose intolerance were determined in non-diabetic rats. On the other hand, STZ group showed insulin resistance and it was impaired in the course of puberty suggesting that the developing of this resistance during the puberty presents a different characteristic of that seen in normal rats.

<p>Fifty children with hematologic malignancies have been treated with autologous BMT in Uppsala. The aim was to describe late effects in this group with special reference to cataracts, reduced final height, and to hepatic, renal, and pulmonary late effects. </p><p>Cataracts: All patients who received TBI in their conditioning developed posterior subcapsular cataract after BMT. A few patients with visual impairment affecting daily life needed cataract surgery, whereas the visual acuity was well preserved in most of the other patients.</p><p>Final height: There was a decrease in final height relative both to height at BMT and to target height. This decrease was significant both in those who had received TBI only and in those who had been given cranial irradiation. Cranial irradiation, young age at BMT, and short duration of GH treatment were predictors of height loss. </p><p>Hepatic function: Hepatic function was well preserved over a period of 10 years after BMT. TBI did not appear to be a risk factor for hepatic impairment. </p><p>Renal function: Six months after BMT there was a decrease in renal function in patients who had received TBI. It then recovered, albeit incompletely, and stabilized. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for the development of chronic renal impairment in a number of patients. Nephrotoxic antibiotics may have contributed.</p><p>Pulmonary function: Six months after BMT there was a decrease in pulmonary function in those who received TBI. It then recovered and stabilized at the pretransplant level. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for restrictive pulmonary disease in a number of patients whereas chemotherapy might also have been of importance for impaired gas exchange.</p>

Fifty children with hematologic malignancies have been treated with autologous BMT in Uppsala. The aim was to describe late effects in this group with special reference to cataracts, reduced final height, and to hepatic, renal, and pulmonary late effects. Cataracts: All patients who received TBI in their conditioning developed posterior subcapsular cataract after BMT. A few patients with visual impairment affecting daily life needed cataract surgery, whereas the visual acuity was well preserved in most of the other patients. Final height: There was a decrease in final height relative both to height at BMT and to target height. This decrease was significant both in those who had received TBI only and in those who had been given cranial irradiation. Cranial irradiation, young age at BMT, and short duration of GH treatment were predictors of height loss. Hepatic function: Hepatic function was well preserved over a period of 10 years after BMT. TBI did not appear to be a risk factor for hepatic impairment. Renal function: Six months after BMT there was a decrease in renal function in patients who had received TBI. It then recovered, albeit incompletely, and stabilized. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for the development of chronic renal impairment in a number of patients. Nephrotoxic antibiotics may have contributed. Pulmonary function: Six months after BMT there was a decrease in pulmonary function in those who received TBI. It then recovered and stabilized at the pretransplant level. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for restrictive pulmonary disease in a number of patients whereas chemotherapy might also have been of importance for impaired gas exchange.

The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.

The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.

Les jeux vidéo entretiennent des liens étroits avec les problématiques pubertaires et la vie psychique des adolescents. Ils répondent à des besoins psychologiques spécifiques du processus pubertaire et permettent d’articuler les émois et les pensées de l’adolescent. En ce sens, les jeux vidéo semblent faire office de contenant utilisé par les adolescents pour transformer leurs états internes et permettent de ressentir en toute sécurité des émotions intenses. Ils mobilisent également une expérience émotionnelle, ils sollicitent l’empathie du joueur, un rapprochement peut se faire entre l’espace du jeu vidéo et ce que D.Winnicott a nommé « l’espace transitionnel », qui se situe entre la réalité externe et réalité interne du joueur, entre le dedans et le dehors. Ainsi, cette thèse interroge la relation qu’entretiennent les joueurs excessifs adolescents avec les jeux vidéo et le type d’interaction qui y est recherchée. A l’aune du modèle théorique de S.Tisseron (2008) distinguant deux types d’interactions sensori-motrice et émotionnelles-narratives à l’œuvre dans le jeu vidéo, cette recherche présente les résultats d’une démarche d’évaluation de 836, dont 582 adolescents et 274 adultes. Les résultats préliminaires attestent que la pratique excessive des jeux vidéo à l’adolescence ne signe en rien une conduite problématique et met en exergue des différences statistiquement significatives entre les pratiques excessives des adolescents et celles des adultes ne relevant pas de la même logique. / Video games have close ties with puberty problems and teenagers psychic life; they meet specific psychological needs of the pubertal process and help to articulate the emotions and thoughts of the youth. In this sense, video games seem to act as a container used by teens to transform their internal states and allow to feel safely intense emotions. They also mobilize an emotional experience and it seeks empathy player. A comparison may be b the way, the space between the video game and what D.Winnicott named "transitional space" which is between external reality and internal reality of the player, between the inside and the outside. This thesis make us question about the young gamblers relationship with video games and the type of interaction that is sought. In the light of the theoretical model, S.Tisseron (2008) distinguishes two types of “sensori-motor” interactions and “emotional–narrative” at work in the video games. This research presents the evaluations results process of 836 players, including 582 adolescents and 274 adults. Preliminary results show that with an excessive playing of video games, teens are in no way a problematic behavior’s sign and highlight statistically, significant differences between the excessive practice of adolescents and those of adults, not covered by the same logic.