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To explore in mice if a 15% food restriction protocol during pregnancy programs the offspring postnatal development, with emphasis on reproductive function, and to assess if ghrelin (Ghrl) administration to mouse dams exerts effects that mimic those obtained under mild caloric restriction. Mice were 15% food-restricted, injected with 4 nmol/animal/day of Ghrl, or injected with the vehicle (control) thorough pregnancy. After birth, the pups did not receive further treatment. Pups born from food-restricted dams (FR pups) were lighter than Ghrl pups at birth, but reached normal weight at adulthood. Ghrl pups were heavier at birth and gained more weight than control pups (C pups). This effect was not associated with plasma IGF-1. FR pups showed a delay in pinna detachment and eye opening, while an advance was observed in Ghrl pups. FR pups showed also impairment in the surface-righting reflex. In both female FR and Ghrl pups, there was an advance in vaginal opening and, in adulthood, FR pups showed a significant decrease in their own litter size and plasma progesterone, and an increase in embryo loss. A delay in testicular descent was evident in male Ghrl pups. Changes in puberty onset were not associated with differences in the expression of Kiss1 in hypothalamic nuclei. Finally, in adulthood, FR pups showed a significant decrease in sperm quality. In conclusion, a mild food restriction thorough gestation exerted programming effects on the offspring, affecting also their reproductive function in adulthood. These effects were not similar to those of intragestational Ghrl administration.

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CONTEXT: Gender incongruence is defined as disharmony between assigned gender and gender identity. Several interventions are liable in this case including genital affirming surgery among other surgical interventions such as harmonization, and also the use of gonadotropin-releasing hormone agonists (GnRHa) for gonadal shielding. This aids in preventing the development of secondary sexual characteristics related to the genetic sex. OBJECTIVE: Systematically review the treatment of gender incongruity with GnRHa analogues. DATA SOURCES: The data source of this research is from Pubmed-Medline and Embase. STUDY SELECTION: Articles published between 2009 and 2019 which studied transgender adolescents treated with GnRHa were carefully selected. DATA EXTRACTION: Were extracted: design, sample size, study context, targeted subjects of intervention, outcome measures, and results. RESULTS: Eleven studies were included. The use of GnRHa seems to be well tolerated by the studied population. When started in pubertal transition, it was associated with a more distinct resemblance to body shape than to the affirmed sex. In addition to preventing the irreversible phenotypic changes that occur in cross-hormonal therapy, the use of GnRHa can equally contribute to the mental health of these adolescents. LIMITATION: There are few consistent studies on the use of GnRHa for gender incongruence. CONCLUSION: As the population of transgender children and adolescents grows, they acquire knowledge and greater access to the various forms and stages of treatment for sex reassignment. The medical community needs to be adequately prepared to better serve this population and offer the safest resources available.

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Autistic spectrum disorders (ASD) are neurodevelopmental disorders that affect social communication and present repetitive, stereotyped and inflexible behaviour. A third of the people with a diagnosis of ASD also have intellectual disability associated and two thirds present an intellectual capacity within the average range. The nuclear autistic and others associated symptoms can affect the affective and sexual development. This article exposes which are the problems people with ASD present in the affective and sexual development, the most frequently described and brief guides for evaluation and support for an adequate affective-sexual development in people with ASD.

Los trastornos del espectro autista (TEA) son trastornos del neurodesarrollo que afectan la comunicación social y que presentan patrones de conducta repetitiva, estereotipada o/y inflexible. Un tercio de los casos diagnosticados de TEA tienen discapacidad intelectual y 2/3 una capacidad intelectual dentro de la norma. Los síntomas nucleares de autismo y otros asociados pueden afectar el desarrollo afectivo-sexual. En este artículo se expone qué dificultades en el desarrollo afectivo-sexual pueden presentar las personas con TEA y cuáles son las más frecuentemente descritas. Se propone de una manera breve, guías dirigidas a la evaluación y a la ayuda para un desarrollo afectivo-sexual satisfactorio en las personas con autismo-TEA.

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Los trastornos del espectro autista (TEA) son trastornos del neurodesarrollo que afectan la comunicación social y que presentan patrones de conducta repetitiva, estereotipada o/y inflexible. Un tercio de los casos diagnosticados de TEA tienen discapacidad intelectual y 2/3 una capacidad intelectual dentro de la norma. Los síntomas nucleares de autismo y otros asociados pueden afectar el desarrollo afectivo-sexual. En este artículo se expone qué dificultades en el desarrollo afectivo-sexual pueden presentar las personas con TEA y cuáles son las más frecuentemente descritas. Se propone de una manera breve, guías dirigidas a la evaluación y a la ayuda para un desarrollo afectivo-sexual satisfactorio en las personas con autismo-TEA.

Autistic spectrum disorders (ASD) are neurodevelopmental disorders that affect social communication and present repetitive, stereotyped and inflexible behaviour. A third of the people with a diagnosis of ASD also have intellectual disability associated and two thirds present an intellectual capacity within the average range. The nuclear autistic and others associated symptoms can affect the affective and sexual development. This article exposes which are the problems people with ASD present in the affective and sexual development, the most frequently described and brief guides for evaluation and support for an adequate affective-sexual development in people with ASD.

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3ßHSD2 enzyme is crucial for adrenal and gonad steroid biosynthesis. In enzyme deficiency states, due to recessive loss-of-function HSD3B2 mutations, steroid flux is altered and clinical manifestations result. Deficiency of 3ßHSD2 activity in the adrenals precludes normal aldosterone and cortisol synthesis and the alternative backdoor and 11-oxygenated C19 steroid pathways and the flooding of cortisol precursors along the Δ5 pathway with a marked rise in DHEA and DHEAS production. In gonads, it precludes normal T and estrogen synthesis. Here, we review androgen-dependent male differentiation of the external genitalia in humans and link this to female development and steroidogenesis in the developing adrenal cortex. The molecular mechanisms governing postnatal adrenal cortex zonation and ZR development were also revised. This chapter will review relevant clinical, hormonal, and genetic aspects of 3ßHSD2 deficiency with emphasis on the significance of alternate fates encountered by steroid hormone precursors in the adrenal gland and gonads. Our current knowledge of the process of steroidogenesis and steroid action is derived from pathological conditions. In humans the 3ßHSD2 deficiency represents a model of nature that reinforces our knowledge about the role of the steroidogenic alternative pathway in sex differentiation in both sexes. However, the physiological role of the high serum DHEAS levels in fetal life as well as after adrenarche remains to be elucidated.

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The aim of this study was to determine if the absence of the mother during rearing has long-term effects on sexual behaviour and physiological reproductive parameters of adult rams. Two groups of rams were: (1) artificially reared, separated from their dams 24 to 36 h after birth (Week 0) and fed using sheep milk until 10 weeks of age (group AR, n=14); and (2) reared by their dams until 10 weeks of age (group DR, n=13). Sexual behaviour (tests of 20 min) and physiological reproductive parameters were analysed separately for the non-breeding (Weeks 42 to 64) and the breeding (Weeks 66 to 90) seasons. Body weight, scrotal circumference, gonado-somatic index, testosterone concentrations or sperm parameters were similar in both rearing conditions (AR v. DR) in both seasons. During the non-breeding season AR rams displayed fewer ano-genital sniffings (AR: 4.2±0.4 v. DR: 5.3±0.4, P=0.04) and matings (AR: 1.2±0.2 v. DR: 1.8±0.2, P=0.002) than DR rams. During the breeding season AR rams displayed fewer ano-genital sniffings (AR: 4.3±0.5 v. DR: 5.7±0.5, P=0.005), flehmen (AR: 0.7±0.2 v. DR: 1.1±0.2, P=0.03), mount attempts (AR: 1.4±0.2 v. DR: 2.1±0.2, P=0.04), and tended to mount less frequently (AR: 6.6±0.9 v. DR: 8.8±0.9, P=0.08) than DR rams. In conclusion, the absence of the mother during the rearing period negatively affected display of sexual behaviour towards oestrous ewes during a rams adult life in both breeding and non-breeding seasons. However, it did not affect testis size, testosterone secretion or sperm variables.

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Virilisation of the XX foetus is the result of androgen excess, resulting most frequently from congenital adrenal hyperplasia in individuals with typical ovarian differentiation. In rare cases, 46,XX gonads may differentiate into testes, a condition known as 46,XX testicular disorders of sex development (DSD), or give rise to the coexistence of ovarian and testicular tissue, a condition known as 46,XX ovotesticular DSD. Testicular tissue differentiation may be due to the translocation of SRY to the X chromosome or an autosome. In the absence of SRY, overexpression of other pro-testis genes, e.g. SOX family genes, or failure of pro-ovarian/anti-testis genes, such as WNT4 and RSPO1, may underlie the development of testicular tissue. Recent experimental and clinical evidence giving insight into SRY-negative 46,XX testicular or ovotesticular DSD is discussed.

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Os fenômenos do desenvolvimento sexual e puberal são eventos progressivos e coordenados. Dependem de fatores cromossômicos - gênicos, gonadais e hormonais. Tais eventos nos indivíduos do sexo masculino e feminino, sendo sincrônicos, permitirão um conveniente desenvolvimento sexual e puberal. Analisar tais fenômenos é o propósito deste estudo.(AU)

The sexual and puberal modifications are coordinate and progressive during differents life phases. Many factors are involved like genic-chromosomic, gonadal and hormonal. Those events that occurred in males and females are synchronous and to create a perfect development. Our proposal is review those situations.(AU)

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Resulta cada vez más necesario que los pediatras tengan mayores conocimientos de salud del adolescente. Para empezar, deben familiarizarse con el desarrollo psicosocial propio de este período, asunto indispensable para la atención del grupo etario. En este artículo se revisa el desarrollo psicosocial normal del adolescente con ese objetivo. La adolescencia es una etapa que se ha ido prolongando progresivamente, en la que ocurren cambios rápidos y de gran magnitud, que llevan a la persona a hacerse tanto biológica, como psicológica y socialmente madura, y potencialmente capaz de vivir en forma independiente. Son tareas del desarrollo de este período, la búsqueda y consolidación de la identidad y el logro de la autonomía. Si bien constituye un proceso de alta variabilidad individual en cuanto a su comienzo y término, a la progresión a través de sus etapas, a la sincronía del desarrollo entre los diversos ámbitos y en otros aspectos, el desarrollo psicosocial de este período tiende a presentar características comunes y un patrón progresivo de 3 fases: adolescencia temprana, media y tardía. En este artículo se describe el desarrollo psicológico, cognitivo, social, sexual y moral de los jóvenes en cada una de ellas.

It is increasingly necessary that pediatricians have greater knowledge of adolescent health. To begin with they should be familiar with the psychosocial development of this period, an issue which is imperative for the health care of the age group. With that purpose, this article reviews the normal adolescent psychosocial development. Adolescence is a stage that has been progressively prolonged, during which fast and big changes occur, that lead human beings to become biologically, psychologically and socially mature, and potentially able to live independently. Developmental tasks of this period are the establishment of identity and the achievement of autonomy. Although it is a process of high individual variability in terms of its beginning and end, the progression through stages, the synchrony of development between the various areas, and in other aspects, the psychosocial development of this period usually have common characteristics and a progressive pattern of 3 phases: early, middle and late adolescence. Psychological, cognitive, social, sexual and moral development of young people in each of them are described in this article.

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It is increasingly necessary that pediatricians have greater knowledge of adolescent health. To begin with they should be familiar with the psychosocial development of this period, an issue which is imperative for the health care of the age group. With that purpose, this article reviews the normal adolescent psychosocial development. Adolescence is a stage that has been progressively prolonged, during which fast and big changes occur, that lead human beings to become biologically, psychologically and socially mature, and potentially able to live independently. Developmental tasks of this period are the establishment of identity and the achievement of autonomy. Although it is a process of high individual variability in terms of its beginning and end, the progression through stages, the synchrony of development between the various areas, and in other aspects, the psychosocial development of this period usually have common characteristics and a progressive pattern of 3 phases: early, middle and late adolescence. Psychological, cognitive, social, sexual and moral development of young people in each of them are described in this article.

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Objetivou-se avaliar o desempenho reprodutivo de ovelhas deslanadas em função do manejo alimentar das crias e idade de desmame, além de mensurar o efeito do sexo no ganho de peso de cordeiros. Sessenta e quatro ovelhas mestiças da raça Santa Inês foram distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 4 x 2 x 2 - quatro idades de desmame (56, 70, 84 e 98 dias), sexo e manejo alimentar das crias, cada tratamento com quatro repetições. As ovelhas foram manejadas com a cria ao pé, em 14 piquetes de 1,5 ou 2,0 hectares, formados com pastagem de Brachiaria humidícola. As crias nascidas de partos simples, filhos de reprodutores Santa Inês puros de origem (PO). Após o desmame de todos os grupos, sessenta e quatro cordeiros (32 machos e 32 fêmeas) foram distribuídos ao acaso em baias individuais e confinados por 30 dias. A comparação dos parâmetros foi realizada pelo ajuste do modelo de regressão linear simples. Verificou-se vício de tempo longo do manejo alimentar das crias de + 3,7% (P<0,05) para o intervalo entre partos e de + 1,4% (P<0,05) para o período de serviço. Houve efeito linear crescente (P<0,05) da idade de desmame sobre o intervalo entre partos e período de serviço. Verificou-se vício de tempo longo do sexo das crias de + 2,0% (P<0,05) para o intervalo entre partos e de + 0,8% (P<0,05) para o período de serviço das ovelhas. Constatou-se vício de tempo longo do sexo de + 35,2% e + 36,9% (P<0,05), respectivamente, para o ganho de peso diário de cordeiros do nascimento ao desmame e pós desmame em confinamento. A suplementação das crias em alimentador privativo e a antecipação da idade de desmame reduzem o intervalo entre partos e período de serviço de ovelhas deslanadas em pastagem de Brachiaria humidícula. O sexo da cria é fonte de variação na análise da eficiência reprodutiva de matrizes ovinas e no ganho de peso de cordeiros mestiços da raça Santa Inês do nascimento ao desmame e após o desmame.

The purpose was to evaluate the reproductive performance of woolless ewes due to the feeding management of offsprings and weaning age in addition to measuring the effect of gender on weight gain of lambs. Sixty-four Santa Inês crossbred ewes were distributed in a completely randomized design in a factorial 4 x 2 x 2 - four weaning ages (56, 70, 84 and 98 days), sex and feeding management of the offspring, each treatment with four replications. The ewes were managed with the offsprings at the foot in 14 paddocks of 1,5 or 2,0 hectares, formed with Brachiaria humidícola. The offsprings were born by single birth, of Santa Inês pure of origin (PO). After the weaning of all groups, sixty-four lambs (32 males and 32 females) were randomly assigned in individual stalls and confined for 30 days. The comparison of the parameters was carried out by the adjustment of the simple linear regression model. It was verified over time addiction of the offspring feed management of + 3,7% (P<0,05) for the calving intervals and of + 1,4% (P<0,05) for the service period. There was increasing linear effect (P<0,05) of weaning age on calving intervals and service period. It was verified over time, addiction of the offspring sex of + 2,0% (P<0,05) for the calving intervals and + 0,8% (P<0,05) for the ewes service period. It was observed over time addiction of sex of + 35,2% and + 36,9% (P<0,05), respectively, for the daily weight gain of lambs from birth to weaning and post-weaning in feedlot. The supplementation of the offspring in private feeder and the anticipation of the weaning age reduce the calving intervals and the service period of woolless ewes in Brachiaria humidicula pasture. The offspring sex is the source of variation in the analysis of reproductive efficiency of ewe's mat rices and in the weight gain of Santa Inês crossbred lambs from birth to weaning, and after weaning.

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Objetivou-se avaliar o desempenho reprodutivo de ovelhas deslanadas em função do manejo alimentar das crias e idade de desmame, além de mensurar o efeito do sexo no ganho de peso de cordeiros. Sessenta e quatro ovelhas mestiças da raça Santa Inês foram distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 4 x 2 x 2 - quatro idades de desmame (56, 70, 84 e 98 dias), sexo e manejo alimentar das crias, cada tratamento com quatro repetições. As ovelhas foram manejadas com a cria ao pé, em 14 piquetes de 1,5 ou 2,0 hectares, formados com pastagem de Brachiaria humidícola. As crias nascidas de partos simples, filhos de reprodutores Santa Inês puros de origem (PO). Após o desmame de todos os grupos, sessenta e quatro cordeiros (32 machos e 32 fêmeas) foram distribuídos ao acaso em baias individuais e confinados por 30 dias. A comparação dos parâmetros foi realizada pelo ajuste do modelo de regressão linear simples. Verificou-se vício de tempo longo do manejo alimentar das crias de + 3,7% (P<0,05) para o intervalo entre partos e de + 1,4% (P<0,05) para o período de serviço. Houve efeito linear crescente (P<0,05) da idade de desmame sobre o intervalo entre partos e período de serviço. Verificou-se vício de tempo longo do sexo das crias de + 2,0% (P<0,05) para o intervalo entre partos e de + 0,8% (P<0,05) para o período de serviço das ovelhas. Constatou-se vício de tempo longo do sexo de + 35,2% e + 36,9% (P<0,05), respectivamente, para o ganho de peso diário de cordeiros do nascimento ao desmame e pós desmame em confinamento. A suplementação das crias em alimentador privativo e a antecipação da idade de desmame reduzem o intervalo entre partos e período de serviço de ovelhas deslanadas em pastagem de Brachiaria humidícula. O sexo da cria é fonte de variação na análise da eficiência reprodutiva de matrizes ovinas e no ganho de peso de cordeiros mestiços da raça Santa Inês do nascimento ao desmame e após o desmame.(AU)

The purpose was to evaluate the reproductive performance of woolless ewes due to the feeding management of offsprings and weaning age in addition to measuring the effect of gender on weight gain of lambs. Sixty-four Santa Inês crossbred ewes were distributed in a completely randomized design in a factorial 4 x 2 x 2 - four weaning ages (56, 70, 84 and 98 days), sex and feeding management of the offspring, each treatment with four replications. The ewes were managed with the offsprings at the foot in 14 paddocks of 1,5 or 2,0 hectares, formed with Brachiaria humidícola. The offsprings were born by single birth, of Santa Inês pure of origin (PO). After the weaning of all groups, sixty-four lambs (32 males and 32 females) were randomly assigned in individual stalls and confined for 30 days. The comparison of the parameters was carried out by the adjustment of the simple linear regression model. It was verified over time addiction of the offspring feed management of + 3,7% (P<0,05) for the calving intervals and of + 1,4% (P<0,05) for the service period. There was increasing linear effect (P<0,05) of weaning age on calving intervals and service period. It was verified over time, addiction of the offspring sex of + 2,0% (P<0,05) for the calving intervals and + 0,8% (P<0,05) for the ewes service period. It was observed over time addiction of sex of + 35,2% and + 36,9% (P<0,05), respectively, for the daily weight gain of lambs from birth to weaning and post-weaning in feedlot. The supplementation of the offspring in private feeder and the anticipation of the weaning age reduce the calving intervals and the service period of woolless ewes in Brachiaria humidicula pasture. The offspring sex is the source of variation in the analysis of reproductive efficiency of ewe's mat rices and in the weight gain of Santa Inês crossbred lambs from birth to weaning, and after weaning.(AU)

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Avaliou-se o desenvolvimento de jundiás Rhamdia quelen submetidos a diferentes temperaturas (19, 24 e 29ºC) nas fases de fertilização, incubação e larvicultura (fase 1) e, na fase de alevinagem (fase2),determinou-se a proporção sexual dos peixes quando mantidos em temperatura constante. Na fase 1 foram avaliadas a sobrevivência, o peso e o comprimento total, sendo que durante a larvicultura, as unidades experimentais utilizadas foram aquários plásticos de 7 L, estocados com 20 larvas L-¹. Na fase 2 foram utilizados tanques circulares de 80 L conectados a um sistema de recirculação de água, estocados com 60 juvenis. Mensalmente foi verificada a sobrevivência, o peso, o comprimento total, o consumo, a conversão alimentar aparente (CAA), a taxa de crescimento específico (TCE) e, ao final do experimento, a proporção sexual dos juvenis. A sobrevivência foi menor (P<0,05) na temperatura mais baixa durante a fase 1 e manteve-se a mesma ao final da fase 2. Não houve influência da temperatura sobre o peso final dos animais (P>0,05) nas duas fases, porém o comprimento das larvas criadas na temperatura mais baixa foi menor ao final da fase 1 (19ºC: 1,78±0,39cm; 24ºC: 2,32±0,33cm; 29ºC: 2,49±0,56 cm), assim como dos juvenis na fase 2 (19ºC: 7,42±0,91cm; 24ºC: 8,28±0,96cm; 29ºC: 8,56±0,95 cm), enquanto o consumo, a CAA e a TCE apresentaram melhor resposta com o aumento da temperatura. O número de machos produzido foi superior ao de fêmeas, porém a proporção sexual não foi afetada pela temperatura.(AU)

Evaluated the development of jundiás Rhamdia quelen subjected to different temperatures (19, 24 and 29ºC) in the phases of fertilization, hatching and larval rearing (phase1) and in phase nursery (phase 2), determined the sex ratio fish when kept at constant temperature. In Phase 1 the survival, weight and total length were evaluated, and during the hatchery 7-L plastic tanks, stocked with 20 larvae L-¹ were used as experimental units. Phase 2 used 60 fingerlings stocked in 80-L circular tanks connected to a recirculating water system. Monthly, the survival, weight, total length, feed consumption, feed conversion rate (FCR) and specific growth rate (SGR) were measured, and also the sex ratio of fingerlings at the end of the experiment. Survival was lower (P<0.05) in colder temperature during phase 1 and remained the same at the end of phase 2. No influence of temperature was registered on the final weight of animals (P>0.05) in both phases, but total length for larvae and for fingerlings reared on colder temperature were lower at the end of phase1 (19°C: 1.78 ± 0.39 cm; 24°C: 2.32 ± 0.33cm; 29°C: 2.49 ± 0.56 cm) and 2 (19°C: 7.42 ± 0.91cm; 24°C: 8.28 ± 0.96 cm; 29°C: 8.56 ± 0.95 cm), respectively, while consumption, FCR and SGR showed better response with temperature increase. The number of males produced was higher than females, but the sex ratio was not affected by the temperature.(AU)

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BACKGROUND: Recent studies have supported the concept of "fetal programming" which suggests that during the intrauterine development the fetus may be programmed to develop diseases in adulthood. The possible effects of in utero protein restriction on sexual development of rat male offspring were evaluated in the present study. METHODS: Pregnant Wistar rats were divided into two experimental groups: one group treated with standard chow (SC, n = 8, 17% protein) and the other group treated with hypoproteic chow (HC, n = 10, 6% protein) throughout gestation. After gestation the two experimental groups received standard chow. To evaluate the possible late reproductive effects of in utero protein restriction, the male offspring of both groups were assessed at different phases of sexual development: prepubertal (30 days old); peripubertal (60 days old); adult (90 days old). Student's t-test and Mann-Whitney test were utilized. Differences were considered significant when p < 0.05. RESULTS: We found that in utero protein restriction reduced the body weight of male pups on the first postnatal day and during the different sexual development phases (prepubertal, peripubertal and adult). During adulthood, Sertoli cell number, sperm motility and sperm counts in the testis and epididymal cauda were also reduced in HC. Furthermore, the numbers of sperm presenting morphological abnormalities and cytoplasmic drop retention were higher in HC. CONCLUSIONS: In conclusion, in utero protein restriction, under these experimental conditions, causes growth delay and alters male reproductive-system programming in rats, suggesting impairment of sperm quality in adulthood.

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The study of ovarian folliculogenesis has been of great interest to scientists and clinicians in the human and veterinary health fields for more than 20 centuries. Initial studies of the ovarian follicle were based on anatomical descriptions post-mortem, followed by histologic and endocrinologic evaluation of ovarian status. The introduction of high resolution ultrasonography in the 1980s provided a long-awaited tool to image the reproductive tissues in situ in both animal and human species. The bovine and equine species have been established as models for the study of human ovarian folliculogenesis. Profound similarities in the dynamics of follicle development exist between the menstrual cycle in humans and the estrous cycle in cattle and horses. Disparities between species appear specific rather than general. Research performed in women thus far has led to the concepts that: 1) follicle development occurs in a wave-like manner during the menstrual cycle, 2) the number of waves per cycle correlates positively with the length of the cycle, 3) the emergence of follicle waves in women are preceded by a rise in circulating FSH, 4) selection of a dominant follicle may occur in each wave of the cycle, and 5) a decline in circulating FSH and increase in follicular estradiol, inhibin A, and IGF-II act collectively to enable the dominant follicle to continue to grow in an endocrine environment of decreasing FSH and increasing LH, while subordinate follicles undergo regression. The goal of continued research using animal models for studying human ovarian function is to provide the hypothetical basis for further studies in women, which will ultimately lead to the development of safer and more efficacious infertility and contraceptive therapies.(AU)

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The study of ovarian folliculogenesis has been of great interest to scientists and clinicians in the human and veterinary health fields for more than 20 centuries. Initial studies of the ovarian follicle were based on anatomical descriptions post-mortem, followed by histologic and endocrinologic evaluation of ovarian status. The introduction of high resolution ultrasonography in the 1980s provided a long-awaited tool to image the reproductive tissues in situ in both animal and human species. The bovine and equine species have been established as models for the study of human ovarian folliculogenesis. Profound similarities in the dynamics of follicle development exist between the menstrual cycle in humans and the estrous cycle in cattle and horses. Disparities between species appear specific rather than general. Research performed in women thus far has led to the concepts that: 1) follicle development occurs in a wave-like manner during the menstrual cycle, 2) the number of waves per cycle correlates positively with the length of the cycle, 3) the emergence of follicle waves in women are preceded by a rise in circulating FSH, 4) selection of a dominant follicle may occur in each wave of the cycle, and 5) a decline in circulating FSH and increase in follicular estradiol, inhibin A, and IGF-II act collectively to enable the dominant follicle to continue to grow in an endocrine environment of decreasing FSH and increasing LH, while subordinate follicles undergo regression. The goal of continued research using animal models for studying human ovarian function is to provide the hypothetical basis for further studies in women, which will ultimately lead to the development of safer and more efficacious infertility and contraceptive therapies.

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Objetivo: Verificar a influência da maturação sexual sobre as variáveis de aptidão física de acordo com a faixa etária em escolares do sexo masculino do município de Ilhabela em uma abordagem longitudinal. Método: 27 escolares do sexo masculino foram acompanhados por um período de 4 anos consecutivos, entre 10 e 13 anos de idade. As variáveis avaliadas foram: massa corporal, estatura, adiposidade, impulsão vertical, shuttle run, corrida de 50 metros e a potência aeróbica (VO2máx l.min-1 e ml.kg-1.min-1), seguindo a padronização do CELAFISCS. A determinação do nível maturacional foi feita mediante a auto-avaliação dos pêlos púbicos proposta por Matsudo (1994). A análise estatística utilizada foi a análise de regressão univariada. O nível de significância adotado foi p<0,05. Resultados: A maturação sexual explicou de maneira significativa a adiposidade aos 10, 11 e 12 anos, a força aos 10 e 12 anos, a velocidade e a potência aeróbica (VO2máx l.min-1) apenas aos 10 anos. Conclusão: A maturação sexual explica principalmente a adiposidade, mas também a força, a velocidade e a potência aeróbica em termos absolutos (VO2máx l.min-1) do que as outras variáveis analisadas dos 10 aos 13 anos de idade no sexo masculino. A agilidade e o VO2máx (ml.kg-1.min-1) não foram explicadas pela maturação em qualquer das idades avaliadas.

Purpose: The aim of the present study was to verify through a longitudinal approach the influence of the sexual maturation on physical fitness according to age in peri-pubertal boys Methods: 27 male students from 10 to 13 years of age were followed during 4-year period. Variables analyzed were: body weight, height, adiposity, vertical jump, shuttle run, 50 meters run test and aerobic power (VO2máx - l.min-1 and ml.kg-1.min-1), according to CELAFISCS standard. Sexual maturation level was established through the self-assessment of Tanner (1991) stages, considering pubic hair, proposed by Matsudo (1994). Each student participated in, at least, one evaluation per year. Results were evaluated through univariate regression analysis. Level of significantly adapted was p<0.05. Results: Sexual maturation significantly accounted to adiposity values among 10, 11 and 12 years-old boys, to strength in the 10 and 12 years-old groups, and speed and aerobic power (VO2máx l.min-1) values only in the 10 years-old group. Conclusion: Based on this longitudinal study authors concluded that among peri-pubertal boys. Sexual maturation explained mainly adiposity values. Some strength, velocity, and aerobic power (absolute value). No influence was observed on agility and relative aerobic power.

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RESUMO

Utilizaram-se quatro touros selecionados por meio de exame andrológico (medida da circunferência escrotal e avaliação das qualidades físicas e morfológicas do sêmen) e de comportamento sexual (libido) que os classificaram entre muito bons e excelentes. Organizaram-se dois grupos experimentais, G1 e G2, o primeiro composto por dois touros e 200 vacas, estabelecendo, assim, a proporção de um touro para 100 vacas e o segundo, considerado como testemunha, por dois touros e 100 vacas, portanto, proporção de 1:50. Todas as matrizes eram da raça Nelore, pluríparas, não gestantes e secas. A estação de monta durou 72 dias. As taxas de gestação obtidas aos 30, 60 e 72 dias, medidas a partir dos nascimentos das crias, foram de 54,0 por cento e 57,0 por cento (P>0,05), 79,5 por cento e 82,0 por cento (P>0,05) e 87,0 por cento e 88,0 por cento (P>0,05), para os animais dos grupos G1 e G2, respectivamente. Reprodutores Nelore selecionados por meio de exames andrológicos e comportamentais (teste da libido) podem suportar até 100 vacas em estação de monta curta, com vantagens econômicas e para a eficiência reprodutiva atual e futura do rebanho, desde que observadas as regras de manejo pré-estabelecidas. A análise dos resultados revelou economia de 25,6 por cento sobre o custo da cria desmamada em comparação com proporção simulada de 1:25 (4 por cento de touros) tradicionalmente utilizada na pecuária de corte brasileira.

Four sexually mature Nellore bulls evaluated for sexual soundness using physical and morphological characteristics of semen and scrotal circumference and sexual behavior (libido), were selected after qualifying either as very good or excellent. The chosen bulls were randomly divided into two experimental groups: group 1 - two bulls for mating 200 cows (1:100 ratio), and group 2 - two bulls for mating 100 cows (1:50 ratio). Females were pluriparous, opened, and non-nursing Nellore. Pregnancy rates on 30, 60 and 72 days during the breeding season, measured through birth date of the calves, were 54.0 percent vs. 57.0 percent (P>0.05), 79.5 percent vs. 82.0 percent (P>0.05), and 87.0 percent vs. 88.0 percent (P>0.05), for groups 1 and 2, respectively. The Nellore breeders selected through physical and morphological characteristics of semen, scrotal circumference and behavior (libido test) were able to bear up to 100 cows during a short breeding season, with economic advantage and genetic gain for the present and future reproductive efficiency of the herd, as long as pre-established management rules are properly followed. Economic analysis revealed a cost reduction of 25.6 percent of the weaned calves when using the proposed 1:100 bull/cow ratio instead of the traditional 1:25 ratio.

Assuntos

RESUMO

Utilizaram-se quatro touros selecionados por meio de exame andrológico (medida da circunferência escrotal e avaliação das qualidades físicas e morfológicas do sêmen) e de comportamento sexual (libido) que os classificaram entre muito bons e excelentes. Organizaram-se dois grupos experimentais, G1 e G2, o primeiro composto por dois touros e 200 vacas, estabelecendo, assim, a proporção de um touro para 100 vacas e o segundo, considerado como testemunha, por dois touros e 100 vacas, portanto, proporção de 1:50. Todas as matrizes eram da raça Nelore, pluríparas, não gestantes e secas. A estação de monta durou 72 dias. As taxas de gestação obtidas aos 30, 60 e 72 dias, medidas a partir dos nascimentos das crias, foram de 54,0% e 57,0% (P>0,05), 79,5% e 82,0% (P>0,05) e 87,0% e 88,0% (P>0,05), para os animais dos grupos G1 e G2, respectivamente. Reprodutores Nelore selecionados por meio de exames andrológicos e comportamentais (teste da libido) podem suportar até 100 vacas em estação de monta curta, com vantagens econômicas e para a eficiência reprodutiva atual e futura do rebanho, desde que observadas as regras de manejo pré-estabelecidas. A análise dos resultados revelou economia de 25,6% sobre o custo da cria desmamada em comparação com proporção simulada de 1:25 (4% de touros) tradicionalmente utilizada na pecuária de corte brasileira.(AU)

Four sexually mature Nellore bulls evaluated for sexual soundness using physical and morphological characteristics of semen and scrotal circumference and sexual behavior (libido), were selected after qualifying either as very good or excellent. The chosen bulls were randomly divided into two experimental groups: group 1 two bulls for mating 200 cows (1:100 ratio), and group 2 two bulls for mating 100 cows (1:50 ratio). Females were pluriparous, opened, and non-nursing Nellore. Pregnancy rates on 30, 60 and 72 days during the breeding season, measured through birth date of the calves, were 54.0% vs. 57.0% (P>0.05), 79.5% vs. 82.0% (P>0.05), and 87.0% vs. 88.0% (P>0.05), for groups 1 and 2, respectively. The Nellore breeders selected through physical and morphological characteristics of semen, scrotal circumference and behavior (libido test) were able to bear up to 100 cows during a short breeding season, with economic advantage and genetic gain for the present and future reproductive efficiency of the herd, as long as pre-established management rules are properly followed. Economic analysis revealed a cost reduction of 25.6% of the weaned calves when using the proposed 1:100 bull/cow ratio instead of the traditional 1:25 ratio.(AU)

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OBJECTIVE: To estimate the prevalence of prehypertension and elevated pulse pressure in adolescents and assess the association between those two conditions and sex, age, sexual development, obesity and physical activity. METHODS: Anthropometrical data and blood pressure were measured in and a questionnaire was applied to 456 adolescents (aged 12 to 17 years) recruited from public and private schools, in the Fonseca district, in the city of Niterói, state of Rio de Janeiro, Brazil, from 2003 to 2004. RESULTS: Thirty nine (8.6%) presented prehypertension (PH) and 13.4%, elevated pulse pressure (PP). At bivariate analysis, PH was significantly associated with sex, age and obesity, with more prevalent in boys aged between 15 and 17 years, and in the obese. Elevated PP was associated with gender only, as it was more prevalent in boys. Sexual maturation did not show an association with PH or elevated PP. Similar correlations were found at logistic regression. PH prevalence odds ratio was 7.7 for sex, 4.3 for age and 4.6 for obesity. Elevated PP prevalence odds ratio was 10.8 for sex. The correlation between PP and physical activity was positive and significant. The elevation of PP was attributable to systolic blood pressure. CONCLUSION: PH and the elevated PP were shown to be present in adolescents from a population with a low prevalence of hypertension, mostly in boys. Further prospective studies are necessary to assess the persistence and the impact of those conditions.

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