Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.462
Filtrar
1.
Eur J Endocrinol ; 184(4): 617-625, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33524006

RESUMO

Objective: To investigate the incidence of hypothalamus-pituitary-gonadal (HPG) axis initiation/recovery after treatment and to identify predictive risk factors for noninitiation/recovery. Methods: A total of 127 consecutive suprasellar germ cell tumor (GCT) patients managed at Peking Union Medical College Hospital (2006-2019) were retrospectively analyzed. Prepubertal patients (followed up until 13 years of age for girls and 14 years of age for boys) and patients with HPG dysfunction (followed up for 2 years) were divided into the initiation/recovery and noninitiation/recovery groups. Results: Of the 127 suprasellar GCT patients, 75 met the follow-up criteria, 28 (37.3%) of whom experienced HPG axis initiation/recovery. Compared to the noninitiation/recovery group, the initiation/recovery group included more males and had shorter delayed diagnosis times, smaller tumor sizes, lower panhypopituitarism rates, thinner pituitary stalk widths, lower visual deficit rates, and higher serum testosterone and estradiol levels. The cutoff values of pituitary stalk width, tumor size, and delayed diagnosis time used to predict noninitiation/recovery were 6.9 mm, 6.9 mm and 1.7 years, respectively. Tumor size ≥6.9 mm (odds ratio (OR) = 7.5, 95% CI: 2.2-25.8, P = 0.001), panhypopituitarism (OR = 5.0, 95% CI: 1.4-17.6, P = 0.013), and delayed diagnosis time ≥1.7 years (OR = 5.7, 95% CI: 1.5-20.7, P = 0.009) were risk factors for noninitiation/recovery. Conclusions: Among suprasellar GCT patients, nearly one-third of prepubertal patients and patients with HPG dysfunction experience HPG axis initiation/recovery after treatment. Tumor size ≥6.9 mm, panhypopituitarism, and delayed diagnosis time ≥1.7 years were identified as predictive risk factors for noninitiation/recovery.


Assuntos
Gônadas/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Hipofisárias/terapia , Recuperação de Função Fisiológica/fisiologia , Adolescente , Idade de Início , Estudos de Casos e Controles , Criança , China/epidemiologia , Feminino , Hormônio Foliculoestimulante/sangue , Seguimentos , Humanos , Hipotálamo/fisiologia , Hormônio Luteinizante/sangue , Masculino , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/reabilitação , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/reabilitação , Prognóstico , Puberdade/sangue , Puberdade/fisiologia , Estudos Retrospectivos , Testosterona/sangue
3.
Crim Behav Ment Health ; 30(2-3): 117-131, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32535969

RESUMO

BACKGROUND: Early puberty is associated with higher than average risk of antisocial behaviour, both in girls and boys. Most studies of such association, however, have focused on psychosocial mediating and moderating factors. Few refer to coterminous hormonal measures. AIM: The aim of this review is to consider the role of hormonal markers as potential mediating or moderating factors between puberty timing and antisocial behaviour. METHOD: A systematic literature search was conducted searching Medline, Embase, Web of Science, Scopus, Psycinfo, Cochrane and Google Scholar. RESULTS: Just eight studies were found to fit criteria, all cross-sectional. Measurements were too heterogeneous to allow meta-analysis. The most consistent associations found were between adrenal hormones-both androgens and cortisol-which were associated with early adrenarche and antisocial behaviours in girls and later adrenarche and antisocial behaviour in boys. CONCLUSIONS: The findings from our review suggest that longitudinal studies to test bidirectional hormone-behaviour associations with early or late puberty would be worthwhile. In view of the interactive processes between hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes, integrated consideration of the hormonal end products is recommended.


Assuntos
Comportamento do Adolescente/psicologia , Adrenarca/psicologia , Transtorno da Personalidade Antissocial/etiologia , Hormônios/sangue , Menarca/fisiologia , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Adolescente , Comportamento do Adolescente/fisiologia , Adrenarca/fisiologia , Androgênios , Transtorno da Personalidade Antissocial/diagnóstico , Transtorno da Personalidade Antissocial/metabolismo , Criança , Feminino , Hormônios Esteroides Gonadais/sangue , Gonadotropinas Hipofisárias/sangue , Humanos , Hidrocortisona/metabolismo , Masculino , Fatores de Tempo
4.
J Sports Sci ; 38(20): 2298-2306, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32543283

RESUMO

This study estimated upper and lower limb bone mineral content (BMC) and bone area (BA) in 48 children tennis players (24 boys, 24 girls) aged 7-13 years. The sample comprised four age groups (8.2 ± 0.44, 9.5 ± 0.13, 10.5 ± 0.33, 12.2 ± 0.58). BMC and BA were measured via DXA, and sexual maturity by the Tanner scale, then used as a binary: prepubertal vs peripubertal. Total training time (TTT) included all playing years. Arms were asymmetric and legs symmetric. Boys were more asymmetric than girls in BMC (18% vs 13%) and BA (11% vs 8%). Pre-pubertal children were less asymmetric than peri-pubertal in BMC (14% vs 18%) and in BA (9.4% vs 10%). Bone growth changed with age and TTT markedly better in the dominant arm. The linear combination of TTT, sex, and maturity binary extracted 59% of BMC asymmetry and only 21% of BA asymmetry. For both bone parameters the sex effect was significant only for the pre-pubertal children. Training time constitutes the best predictor of bone asymmetry compared to age, sex, and maturity; when adequate, playing arm bone hypertrophy may be detectable at the age of 7-8 years. These results have health and performance implications.


Assuntos
Densidade Óssea , Desenvolvimento Ósseo/fisiologia , Extremidade Inferior/fisiologia , Condicionamento Físico Humano/fisiologia , Maturidade Sexual/fisiologia , Tênis/fisiologia , Extremidade Superior/fisiologia , Adolescente , Fatores Etários , Criança , Feminino , Humanos , Masculino , Puberdade/fisiologia , Análise de Regressão , Fatores Sexuais , Fatores de Tempo
5.
Nat Rev Endocrinol ; 16(8): 407-420, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32427949

RESUMO

Hypothalamic kisspeptin neurons serve as the nodal regulatory centre of reproductive function. These neurons are subjected to a plethora of regulatory factors that ultimately affect the release of kisspeptin, which modulates gonadotropin-releasing hormone (GnRH) release from GnRH neurons to control the reproductive axis. The presence of sufficient energy reserves is critical to achieve successful reproduction. Consequently, metabolic factors impose a very tight control over kisspeptin synthesis and release. This Review offers a synoptic overview of the different steps in which kisspeptin neurons are subjected to metabolic regulation, from early developmental stages to adulthood. We cover an ample array of known mechanisms that underlie the metabolic regulation of KISS1 expression and kisspeptin release. Furthermore, the novel role of kisspeptin neurons as active players within the neuronal circuits that govern energy balance is discussed, offering evidence of a bidirectional role of these neurons as a nexus between metabolism and reproduction.


Assuntos
Metabolismo Energético/fisiologia , Kisspeptinas/fisiologia , Reprodução/fisiologia , Animais , Dinorfinas/fisiologia , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Homeostase , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Hipotálamo/citologia , Hipotálamo/fisiologia , Kisspeptinas/genética , Hormônio Luteinizante/fisiologia , Neurocinina B/fisiologia , Neurônios/fisiologia , Ovário/fisiologia , Puberdade/fisiologia
6.
J Sport Health Sci ; 9(3): 265-273, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32444151

RESUMO

OBJECTIVE: We sought to investigate the longitudinal associations of moderate-to-vigorous physical activity (MVPA) and pubertal development with academic achievement in adolescents. METHODS: A total of 635 adolescents (283 boys, 352 girls) aged 11-13 years participated in the study. MVPA was assessed by the Health Behaviour in School-aged Children study questionnaire, and pubertal development was assessed by the Pubertal Development Scale at beginning of the 6th grade (baseline) and end of the 7th grade (follow-up). Grade point average (GPA) at the end of Grades 5 and 7 was computed from data acquired from the school registers. The data were analyzed using linear regression and analyses of covariance. RESULTS: In boys, MVPA was positively associated with GPA at baseline after adjustment for age (ß = 0.144, 95% confidence interval (CI): 0.028-0.260, p = 0.028). In girls, the Pubertal Development Scale was positively associated with GPA at baseline (ß = 0.104, 95%CI: -0.004 to 0.211, p = 0.058) and follow-up (ß = 0.104, 95%CI: -0.002 to 0.211, p = 0.055) after adjustment for age, and these associations strengthened after further adjustment for MVPA (p < 0.05). Adolescents who were inactive at baseline or at baseline and follow-up had lower GPA during follow-up than their continuously highly active peers (mean difference = -0.301, 95%CI: -0.543 to -0.058, p = 0.009) and all other adolescents (mean difference = -0.247, 95%CI: -0.475 to -0.019, p = 0.029). These differences were greater in girls than in boys. CONCLUSION: Lower levels of MVPA were associated with lower GPA in boys at baseline. Girls who were continuously inactive had lower GPA over the follow-up period than those who were continuously active. Finally, earlier pubertal development was associated with better academic achievement in girls.


Assuntos
Sucesso Acadêmico , Exercício Físico/fisiologia , Puberdade/fisiologia , Adolescente , Criança , Feminino , Finlândia , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Comportamento Sedentário , Autorrelato , Fatores Sexuais
7.
Health Qual Life Outcomes ; 18(1): 93, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252769

RESUMO

BACKGROUND: The study aimed to analyze the association between pubertal development stages and adiposity in children and adolescents. METHODS: Cross-sectional study conducted in 2007 in Florianópolis, Brazil, with 2339 schoolchildren 32 aged 8 to 14 years old (1107 males). The outcome (adiposity) was evaluated using Z score and 33 percentilee values > = 85 of four skinfolds (triceps, subscapular, suprailiac and calf) and waist 34 circumference. Total body adiposity (Z score of the sum of skinfolds), central adiposity (Z score 35 of waist circumference) and peripheral adiposity (Z scores of triceps and calf skinfolds) were 36 estimated. Pubertal development stages was self-assessed according to Tanner stages of development. Thirty-seven Children and adolescents were classified according to tertiles of age for each pubertal development stages 38 stage - early, normal and late. Statistical analysis was performed using univariate and 39 multivariate Poisson regression models. RESULTS: Children and adolescent from both sexes with early pubertal development stages presented higher prevalence of central adiposity (waist circumference), with adjusted prevalence ratio (CI 95%) of 2.21 (1.12; 4.35) for males and 2.18 (1.04; 4.57) for females (reference group: normal pubertal development stages). Among females, there was a reduction in the prevalence of excess adiposity with decreased occurrence of early pubertal development stages. There was a strong relationship between adiposity and pubertal development stages. CONCLUSIONS: Excess adiposity was higher in both sexes for those with early pubertal development stages.


Assuntos
Adiposidade , Obesidade Abdominal/epidemiologia , Puberdade/fisiologia , Adolescente , Índice de Massa Corporal , Brasil/epidemiologia , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Qualidade de Vida , Estudantes/estatística & dados numéricos , Circunferência da Cintura
8.
Eur J Endocrinol ; 183(1): 13-20, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32348954

RESUMO

Objective: Pubertal timing is highly heritable. Observational studies were inconclusive concerning a potential sex-specific difference in the parental contribution, while genome-wide association studies highlighted a heterogeneity in the genetic architecture of pubertal timing between sexes. Our objectives were to evaluate the association of timing of pubertal milestones in offspring with parental pubertal timing and to identify the genetic basis of the heterogeneity. Design: (1.) Population-based mixed cross-sectional/longitudinal cohort (2006-2014, COPENHAGEN Puberty Study) comprising 1381 healthy Danish children including their parents. (2.) UK Biobank-based summary statistics of genetic data on timing of menarche (n = 188 644), voice-break (n = 154 459) and facial hair (n = 161 470). Methods: (1.) Participants underwent clinical examination(s) including blood sampling. Parental pubertal timing was obtained by questionnaire. Timing of milestones were analyzed using SAS-lifereg. (2.) Genetic correlations between pubertal outcomes were estimated using LD Score regression. Genetic heterogeneity was analyzed using METAL. Results: We observed significant associations of relative parental pubertal timing with timing of pubertal milestones in offspring of concordant sex, that is, fathers/sons (e.g. testicular enlargement: P = 0.004, ß = 0.34 years per relative category) and mothers/daughters (e.g. thelarche: P < 0.001, ß = 0.45 years per relative category). Fewer milestones were associated with relative parental pubertal timing in offspring of discordant sex compared to concordant sex. Large-scale genetic data highlight both moderate to strong genetic correlations between timing of menarche, voice-break and facial hair. Out of 434 lead single-nucleotide polymorphisms significantly associated with at least one outcome, 39 exhibited a significant genetic heterogeneity between sexes (P < 1.15 × 10-4). Conclusion: Our results highlight a distinct genetic heterogeneity of pubertal timing between sexes.


Assuntos
Puberdade/genética , Puberdade/fisiologia , Caracteres Sexuais , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Menarca/genética , Menarca/fisiologia , Pais
9.
Dev Cogn Neurosci ; 42: 100753, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32072931

RESUMO

Adolescence may mark a sensitive period for the development of higher-order cognition through enhanced plasticity of cortical circuits. At the same time, animal research indicates that pubertal hormones may represent one key mechanism for closing sensitive periods in the associative neocortex, thereby resulting in decreased plasticity of cortical circuits in adolescence. In the present review, we set out to solve some of the existing ambiguity and examine how hormonal changes associated with pubertal onset may modulate plasticity in higher-order cognition during adolescence. We build on existing age-comparative cognitive training studies to explore how the potential for change in neural resources and behavioral repertoire differs across age groups. We review animal and human brain imaging studies, which demonstrate a link between brain development, neurochemical mechanisms of plasticity, and pubertal hormones. Overall, the existent literature indicates that pubertal hormones play a pivotal role in regulating the mechanisms of experience-dependent plasticity during adolescence. However, the extent to which hormonal changes associated with pubertal onset increase or decrease brain plasticity may depend on the specific cognitive domain, the sex, and associated brain networks. We discuss implications for future research and suggest that systematical longitudinal assessments of pubertal change together with cognitive training interventions may be a fruitful way toward a better understanding of adolescent plasticity. As the age of pubertal onset is decreasing across developed societies, this may also have important educational and clinical implications, especially with respect to the effects that earlier puberty has on learning.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Plasticidade Neuronal/fisiologia , Puberdade/fisiologia , Criança , Feminino , Humanos , Masculino
11.
J Clin Res Pediatr Endocrinol ; 12(Suppl 1): 41-45, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041391

RESUMO

For girls with physical and developmental disabilities and their families/caregivers, puberty and menstruation can present significant problems such as vulnerability, abuse risk, unintended pregnancies, difficulties with managing menstrual hygiene, abnormal uterine bleeding, dysmenorrhea, behavioral difficulties/mood concerns or changes in seizure pattern. Healthcare providers may have an important and positive impact for both the adolescents and their families/caregivers during this stage of life. Whether menstrual manipulation is indicated should be decided after a detailed history is taken from both the patient and the caregivers to determine the impact of current problems on quality of life. It should be explained that complete amenorrhea is difficult to achieve and realistic expectations should be addressed. The goals for the management of menstrual concerns should be a reduction in the amount and total days of menstrual flow, reduction of menstrual pain and suppression of ovulatory or cyclic symptoms, depending on each individual patient's needs. Advantages and disadvantages of available treatment methods should also be discussed.


Assuntos
Deficiências do Desenvolvimento/fisiopatologia , Menstruação , Puberdade/fisiologia , Adolescente , Abuso Sexual na Infância/prevenção & controle , Epilepsia/tratamento farmacológico , Feminino , Humanos , Menstruação/efeitos dos fármacos , Síndrome Pré-Menstrual/tratamento farmacológico , Educação Sexual
12.
J Pediatr Adolesc Gynecol ; 33(4): 339-342, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32035994

RESUMO

STUDY OBJECTIVE: Puberty is a normal process for adolescents, and the first signs may include change in body odor, breast development, or pubic hair growth. This is then followed by menarche approximately 2 years later. Vaginal bleeding in pre-pubertal female individuals is rare. The aim of this study was to investigate causes of pre-pubertal bleeding in a group of patients. DESIGN, SETTING, METHOD, AND MAIN OUTCOME MEASURES: Seventeen patients who presented with pre-pubertal recurrent vaginal bleeding with no other signs of precocious puberty were investigated, to determine the cause of this symptom. RESULTS: The mean age for the onset of vaginal bleeding was 7.4 years, ranging from 4 to 9.67 years. Gonadotrophin-releasing hormone (GnRH) stimulation tests showed a pre-pubertal response in all cases. Pelvic ultrasound scans showed a pre-pubertal uterus in all patients. Two patients were found to have foreign bodies identified during a genital examination under anesthetic, and in both cases removal of the foreign bodies terminated the vaginal bleeding. CONCLUSION: In conclusion, recurrent vaginal bleeding was not associated with GnRH response, raised estradiol levels, or abnormal pelvic ultrasound findings. In cases of recurrent vaginal bleeding with normal hormonal investigations in pre-pubertal girls, it is recommended that a genital examination under anesthetic be undertaken to rule out undiagnosed causes of the presenting symptom.


Assuntos
Puberdade Precoce/etiologia , Hemorragia Uterina/etiologia , Criança , Pré-Escolar , Feminino , Hormônio Liberador de Gonadotropina/análise , Exame Ginecológico/métodos , Humanos , Puberdade/fisiologia , Ultrassonografia , Hemorragia Uterina/diagnóstico
13.
Metabolism ; 105: 154187, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32084430

RESUMO

BACKGROUND: S100A4 is a metastasis-associated protein also reported as a promising marker for dysfunctional white adipose tissue (WAT) and insulin resistance (IR) in adult and adolescent populations. OBJECTIVE: We aimed to evaluate the association between the protein S100A4 and obesity and IR in children and during pubertal development. DESIGN AND METHODS: The study design consisted of three cross-sectional populations of 249, 11 and 19 prepubertal children respectively (named study population 1, 2 and 3), and a longitudinal population of 53 girls undergoing sexual maturation (study population 4). All subjects were classified into experimental groups according to their sex, obesity and IR status. All study populations counted on anthropometry, glucose, and lipid metabolism, inflammation and cardiovascular biomarkers as well as S100A4 plasma levels measured. The study population 1 was intended as the discovery population in which to elucidate the relationship between Obesity-IR and S100A4 plasma levels in prepubertal children. The cross-sectional populations 2 and 3 further counted on WAT gene expression data for investigating the molecular basis of this association. Instead, the longitudinal study population 4 presented blood whole-genome DNA methylation data at each temporal record, allowing deepening into the Obesity-IR-S1004 relationship during puberty as well as deciphering plausible epigenetic mechanisms altering S100A4 plasma levels. RESULTS: S100A4 plasma levels were strongly associated with several metabolic and anthropometric outcomes, namely IR, in prepubertal non-diabetic obese children. We also found highly significant positive associations during the course of puberty between the increase in S100A4 levels and the increase in HOMA-IR (P = 0.0003, FDR = 0.005) and insulin levels (P = 0.0003, FDR = 0.005). Methylation in two-enhancer related CpG sites of the S100A4 region (cg07245635 and cg10447638) was associated with IR biomarkers at the prepubertal stage and with longitudinal changes in these measurements. We further reported an association between visceral WAT (vWAT) S100A4 expression and HOMA-IR, insulin levels and BMI Z-Score, but not with circulating S100A4. CONCLUSIONS: We report for the first time the association of S100A4 with IR and WAT dysfunction in prepubertal populations as well as how the change in plasma S100A4 levels accompanies longitudinal trajectories of IR in children during pubertal development. Moreover, we propose epigenetic changes in two methylation sites and an altered S100A4 vWAT expression as plausible molecular mechanisms underlying this disturbance in obesity.


Assuntos
Resistência à Insulina , Obesidade/sangue , Obesidade/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100/sangue , Antropometria , Glicemia/metabolismo , Criança , Pré-Escolar , Estudos Transversais , Epigênese Genética , Feminino , Regulação da Expressão Gênica/genética , Humanos , Metabolismo dos Lipídeos , Estudos Longitudinais , Masculino , Puberdade/fisiologia , Caracteres Sexuais , Maturidade Sexual
14.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915828

RESUMO

CONTEXT: Voice break, as a landmark of advanced male puberty in genome-wide association studies (GWAS), has revealed that pubertal timing is a highly polygenic trait. Although voice break is easily recorded in large cohorts, it holds quite low precision as a marker of puberty. In contrast, gonadarche and pubarche are early and clinically well-defined measures of puberty onset. OBJECTIVE: To determine whether a polygenic risk score (PRS) of alleles that confer risk for voice break associates with age at gonadarche (AAG) and age at pubarche (AAP) in Chilean boys. EXPERIMENTAL DESIGN: Longitudinal study. SUBJECTS AND METHODS: 401 boys from the Growth and Obesity Chilean Cohort Study (n = 1194; 49.2% boys). MAIN OUTCOME MEASURES: Biannual clinical pubertal staging including orchidometry. AAG and AAP were estimated by censoring methods. Genotyping was performed using the Multi-Ethnic Global Array (Illumina). Using GWAS summary statistics from the UK-Biobank, 29 significant and independent single nucleotide polymorphisms associated with age at voice break were extracted. Individual PRS were computed as the sum of risk alleles weighted by the effect size. RESULTS: The PRS was associated with AAG (ß=0.01, P = 0.04) and AAP (ß=0.185, P = 0.0004). In addition, boys within the 20% highest PRS experienced gonadarche and pubarche 0.55 and 0.67 years later than those in the lowest 20%, respectively (P = 0.013 and P = 0.007). CONCLUSIONS: Genetic variants identified in large GWAS on age at VB significantly associate with age at testicular growth and pubic hair development, suggesting that these events share a genetic architecture across ethnically distinct populations.


Assuntos
Biomarcadores , Herança Multifatorial/genética , Puberdade/genética , Voz/genética , Adolescente , Fatores Etários , Biomarcadores/análise , Criança , Pré-Escolar , Chile , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Humanos , Estudos Longitudinais , Masculino , Puberdade/fisiologia , Projetos de Pesquisa , Fatores Sexuais , Voz/fisiologia
15.
Trop Anim Health Prod ; 52(4): 2011-2021, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31989394

RESUMO

Knowledge of puberty plays an important role in planning livestock breeding. The objective of this study was to evaluate the age of the first sexual behavior and the first fertile sperm production, and the changes of reproductive structures in male Thai indigenous pigs, by using a completely randomized design. Male indigenous piglets were randomly divided into 9 groups; each group of 5 piglets was separately sacrificed at the age of 0 (birth), 1.0, 2.0, 3.0, 3.5, 4.0, 4.5, 5.0, and 5.5 months to collect data from the carcasses. The other 3 male pigs were used to test the reproductive ability by natural insemination. The results showed that the first sexual behavior occurred at 2.6 + 0.6 months of age, and the first appearance of fertile sperm mass in the cauda epididymis was in the 4-month group. The semen quality standard was discovered in the 5-month group, and the success of insemination with a fertile female pig was found to be at 5.1 + 0.2 months. The changes in the overall size of reproductive tract and testes occurred in 3 stages of development: slight changes were observed in the first 2 months of age; rapid changes were found from 2 to 4.5 months of age; and gradual changes were detected after 4.5 months of age. Upon examination of semen quality and impregnation ability, it can be concluded that male Thai indigenous pigs attained puberty at the age of 5 months after having manifested sexual behavior for a relatively long period.


Assuntos
Peso Corporal , Puberdade/fisiologia , Comportamento Sexual Animal , Maturidade Sexual , Espermatozoides/fisiologia , Animais , Fertilidade , Masculino , Reprodução , Suínos , Tailândia
16.
J Pediatr Endocrinol Metab ; 33(1): 121-128, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31851614

RESUMO

Background Puberty is the period of human growth and development. To determine the onset of puberty with regards to the effect of higher adiposity, together with growth parameters of the participants at various stages of sexual maturity for both sexes. Methods The study was conducted on 1944 children (8-16) years; 1022 girls (52.6%) and 922 boys (47.4%) were taken at random. Pubertal assessment was done using Tanner staging that assigned breast development in females and pubic and axillary hair in males and females. Testicular volume was recorded using a Prader orchidometer. Height, weight, body mass index (BMI), body mass (BM) fat, body fat percentage, through applying a body impedance analyzer, and others were recorded. Results The mean ages at the onset of puberty for females and males in our study were 10.29 ± 1.1 and 11.34 ± 1.02 years, respectively. Pubic hair (stage PH2) was attained at mean age of 10.72 ± 0.84 and 11.98 ± 1.03 years for females and males, respectively. For axillary hair (stage AH2), the mean age was 12.47 ± 0.68 years for females and 13.8 ± 0.58 years for males. The mean age at menarche was 12.41 ± 0.65 years. In concordance to BM fat and percentage, all pubertal stages started earlier in females with BMI ≥85th percentile comparable to females within average BMI. As for males, no significant relation was noted between mean pubertal ages and BMI values. Conclusions A significant association of mean ages of Tanner stages to excess weight especially in females warranted the increasing awareness about health care, nutritional aspects, and living circumstances.


Assuntos
Composição Corporal , Índice de Massa Corporal , Peso Corporal , Obesidade/fisiopatologia , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Adiposidade , Adolescente , Idade de Início , Criança , Estudos Transversais , Egito/epidemiologia , Feminino , Humanos , Masculino , Obesidade/epidemiologia
17.
Curr Opin Endocrinol Diabetes Obes ; 27(1): 82-86, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31789832

RESUMO

PURPOSE OF REVIEW: To discuss treatments used to enhance growth in pediatric patients with short stature. RECENT FINDINGS: New data confirm the known efficacy of recombinant human growth hormone (rhGH) in growth hormone deficiency (GHD) and idiopathic short stature. The latest data from the Safety and Appropriateness of Growth hormone Treatment in Europe cohort did not indicate a long-term risk of malignancy in those treated for isolated GHD, but possibly increased risk in those with other diagnoses. Recombinant human insulin-like growth factor 1 is effective in treating patients with pregnancy-associated plasma protein A2 deficiency. Gonadotropin-releasing hormone agonists or aromatase inhibitor treatment to delay puberty remains controversial. They are more likely to augment adult height if combined with rhGH treatment in children already receiving rhGH. Preliminary data indicate that recombinant C-type natriuretic peptide (CNP) is safe in children and increases growth velocity upon 42 months of treatment in achondroplasia. SUMMARY: Recent data confirms previous data on rhGH efficacy and safety. Therapies to delay growth plate closure have greatest efficacy to augment height if combined with GH in select diagnoses. Recombinant CNP holds promise as a medical treatment for short stature associated with achondroplasia.


Assuntos
Endocrinologia , Transtornos do Crescimento/prevenção & controle , Transtornos do Crescimento/terapia , Hormônio do Crescimento Humano/deficiência , Adulto , Estatura/efeitos dos fármacos , Criança , Nanismo Hipofisário/tratamento farmacológico , Nanismo Hipofisário/epidemiologia , Endocrinologia/métodos , Endocrinologia/tendências , Europa (Continente)/epidemiologia , Transtornos do Crescimento/epidemiologia , Terapia de Reposição Hormonal/métodos , Terapia de Reposição Hormonal/tendências , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/uso terapêutico , Puberdade/efeitos dos fármacos , Puberdade/fisiologia , Proteínas Recombinantes/uso terapêutico
18.
J Youth Adolesc ; 49(7): 1393-1405, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31587175

RESUMO

Some prior studies have found that, for boys, earlier puberty is linked to higher crime and delinquency, while other studies have found that earlier puberty is associated with greater social competence and beneficial psychosocial development. The current study suggests that these seemingly contradictory results actually represent two divergent pathways by which earlier pubertal timing can affect adjustment. Which pathway boys take is highly dependent on psychosocial context. Using a sample of 310 African American boys and their primary caregivers tracked across three waves of data collection from ages 10.55-18.84 from the Family and Community Health Study (FACHS), the current study utilizes Latent Moderated Structural Equation Modeling (LMS) to analyze effects of interactions between pubertal timing and social contextual factors on criminal behavior and social competence. Results suggest that criminogenic effects of early puberty are contingent on deviant peer group, poor school experience, harsh parenting, and neighborhood disorganization, whereas the association between earlier puberty and social competence is attenuated by harsh parenting. Results suggest that modeling both positive and negative development outcomes together may give a clearer picture of the developmental consequences of pubertal timing for boys. In addition, this study shows the importance of social context in shaping the meaning and consequences of biological variables like pubertal timing.


Assuntos
Afro-Americanos/estatística & dados numéricos , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Habilidades Sociais , Adolescente , Criança , Transtornos do Comportamento Infantil/epidemiologia , Humanos , Masculino , Poder Familiar/psicologia , Grupo Associado , Puberdade/psicologia , Características de Residência , Meio Social
19.
Med Sci Sports Exerc ; 52(3): 598-607, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31652236

RESUMO

INTRODUCTION/PURPOSE: Limited studies have examined the association of physical activity with reproductive hormones, DNA methylation, and pubertal status among adolescents. METHODS: Among 248 boys and 271 girls, we estimated daily physical activity levels based on 7 d of wrist-worn accelerometer data. We used an isotemporal substitution paradigm and sex-stratified regression models to examine the association of physical activity levels with 1) testosterone, cortisol, progesterone, and androstenedione concentrations; 2) DNA methylation of long interspersed nucleotide (LINE-1) repeats and the genes H19, hydroxysteroid (11-Beta) dehydrogenase 2 (HSD11B2), and peroxisome proliferator-activated receptor alpha (PPARA) from blood leukocytes; and 3) Tanner stages, adjusted for age, BMI, and socioeconomic status. RESULTS: In boys, substituting 30 min of moderate physical activity for 30 min of sedentary behavior per day was associated with 29% (-49%, 0%) of lower testosterone and 29% (4%, 61%) of higher progesterone. Substituting 30 min of light physical activity for sedentary behavior was associated with 13% (-22%, -2%) of lower progesterone. Among girls, 30 min of additional sedentary behavior was associated with 8% (-15%, 0%) of lower testosterone and 24% (8%, 42%) of higher progesterone concentrations. Substituting 30 min of moderate physical activity for sedentary behavior was associated with 15% (0%, 31%) of higher cortisol, whereas substituting the same amount of light physical activity for sedentary behavior was associated with 22% (-39%, 0%) of lower progesterone. Substituting 30 min of vigorous physical activity for sedentary behavior per day was associated with almost six times higher levels (5.83, 95% confidence interval = 1.79-9.86) of HSD11B2 methylation in boys. CONCLUSIONS: Accelerometer-measured daily physical activity was associated with reproductive hormones and HSD11B2 DNA methylation, differed by sex and activity intensity levels.


Assuntos
Metilação de DNA , Exercício Físico/psicologia , Hormônios Esteroides Gonadais/sangue , Puberdade/fisiologia , Acelerometria , Androstenodiona/sangue , Índice de Massa Corporal , Feminino , Humanos , Hidrocortisona/sangue , Leucócitos , Masculino , Progesterona/sangue , Comportamento Sedentário , Maturidade Sexual/fisiologia , Fatores Socioeconômicos , Testosterona/sangue
20.
Arthritis Care Res (Hoboken) ; 72(2): 265-273, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31507092

RESUMO

OBJECTIVE: To study growth and puberty in a multinational longitudinal prospective cohort of children with juvenile dermatomyositis (DM). METHODS: Children from 31 countries who were ages <18 years and had juvenile DM in active phase were studied, and analyses of height, weight, and pubertal development were conducted in those who had follow-up visits during a 2-year period and for whom anthropometric data was available. RESULTS: A total of 196 of 275 children (71%) were included. We found a significant reduction in parent-adjusted height Z score over time in female patients (P < 0.0001) and male patients (P = 0.001), but with catch-up growth at the final study visit. Median body mass index Z score peaked at 6 months (P < 0.0001) and was still significantly above baseline at the final study visit, which was at a median of 26 months after baseline (P = 0.007), with no difference between sexes. Female patients with a disease duration ≥12 months after onset had significantly lower parent-adjusted height Z score (P = 0.002) and no 2-year catch-up growth. At the final study visit, growth failure was seen in 20 of 97 female patients (21%) and in 11 of 73 male patients (15%). Height deflection (∆height Z score less than -0.25/year) was observed in 29 of 116 female patients (25%) and 25 of 80 male patients (31.3%). Delayed puberty was seen in 20 of 55 female patients (36.4%) and in 11 of 31 male patients (35.5%). Children in early pubertal stage at baseline had the highest risk of growth failure. CONCLUSION: Juvenile DM in the active phase and/or its treatment has a significant impact on growth and puberty in affected children. Children with recent onset of puberty or previous growth failure have the highest risk of delayed pubertal development and further growth retardation.


Assuntos
Dermatomiosite/diagnóstico , Dermatomiosite/fisiopatologia , Puberdade/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...