Effects of adult-diet modifications on sexual maturation rate, body weight, and quantity of sperm transfer by male Mexican fruit fly (Diptera: Tephritidae).

Mass-reared sterile Mexican fruit flies (Anastrepha ludens [Loew]) are released along the US-Mexico border to control fruit fly damage and spread. It is more cost effective for the mass rearing program if males mature at a younger age because they can be held for a shorter time at the facility before release. In this study, adult male Mexican fruit fly diets were tested to determine if the current diet used at the mass rearing facility promotes younger mating and optimal sperm transfer compared to other diet formulations. Hydrolyzed yeast presentation methods were examined: an agar-free dry mixture of yeast and sugar (Y+S), yeast embedded in the diet during the agar boiling process (current method used) and sifted dry on the ager gel surface. Methoprene, a juvenile hormone analog was also tested as a supplement to agar gel diets with and without yeast. A greater proportion of males fed Y+S mated 1 day earlier than males fed other diets. Male mating age and diet did not significantly affect the quantity of sperm transferred; however, a non-significantly higher percentage of males fed diets with embedded yeast transferred enough sperm to fill all 3 spermathecae. The results suggest that the current diet used is optimal for mass-rearing the flies and that yeast presentation method has a significant effect on A. ludens male mating age but not on the quantity of sperm transferred to females.

Cut-off points in the waist:height ratio for the prediction of insulin resistance, second stage of sexual maturation in Brazilian adolescents.

The objective of this study was verify the best waist:height ratio (WHtR) cut-off points for the prediction of insulin resistance (IR) according to stage of sexual maturation in Brazilian adolescents. Data were analysed from 37 759 adolescents between 12 and 17 years of age, of both sexes, participating in the ERICA study on cardiovascular risk factors in adolescents ('Estudo de Riscos Cardiovasculares em Adolescentes - ERICA'). The following variables were included sex, age and sexual maturity according to the Tanner stage, waist circumference, height, WHtR, fasting insulin and fasting blood sugar so as to obtain the homeostasis model assessment-estimated insulin resistance (HOMA-IR). We constructed an Receiver Operating characteristic (ROC) curve for each group in order to determine the best WHtR cut-off points for the sample stratified by sex and stratified by sex and sexual maturation stage. The female sex corresponded to 60% of the sample, with a mean age of 14·7 years (sd ± 0·08 years) and 13·1 % had IR. The prediction of IR through the WHtR indicator was better for boys, where all the areas under the ROC curve were superior to 0·70. When stratifying by sex alone, the best WHtR cut-off points found were equal to 0·45 for girls and 0·44 for boys. When stratifying by Tanner maturation stages, the cut-off points were reduced with advancing sexual maturation in the male group, while the opposite occurred in the female group. Among Brazilian adolescents, WHtR is a good predictor of IR evaluated by HOMA-IR, but different cut-off points should be adopted according to sex and sexual maturation stage.

Relação entre maturação sexual e indicadores antropométricos e pressóricos em adolescentes / Relationship between sexual maturation and anthropometric and blood pressure indicators in teenagers

Resumo Objetivou-se investigar a relação entre a maturação sexual com indicadores antropométricos e pressóricos de adolescentes. Estudo transversal de base populacional, realizado entre 2018 e 2020, com 345 adolescentes de 10 a 19 anos. Coletou-se variáveis sociodemográficas e antropométricas, pressão arterial e maturação sexual. A análise dos dados foi feita por meio da Análise de Componentes Principais, que gerou três componentes e, posteriormente, testou-se a correlação entre a maturação sexual e os componentes gerados. A maioria dos adolescentes eram do sexo feminino (53%), normotensos (66,1%) e com peso normal (73%). Houve correlação positiva entre o desenvolvimento das mamas com o componente 1 e o componente 2, e correlação negativa entre mamas e o componente 3. Nos meninos, o desenvolvimento dos genitais e pelos pubianos estiveram positivamente correlacionados com o componente 2 e inversamente correlacionados com o componente 3. Conclui-se que existe relação entre a maturação sexual e os indicadores antropométricos e pressóricos, sendo variáveis representativas de risco cardiovascular em adolescentes, mesmo que não em sua totalidade.

Abstract This study aimed to investigate the relationship between sexual maturation and anthropometric and blood pressure indicators in teenagers. This was a population-based cross-sectional study, conducted with 345 teenagers, aged 10 to 19 years, between 2018 and 2020. In this study, data referent to sociodemographic and anthropometric variables, blood pressure, and sexual maturation were collected. The data analysis was performed by applying the Principle Component Analysis (PCA), which generated three components and then tested the correlation between sexual maturation and the generated components. Most of the teenagers were female (53%), normotensive (66.1%), and with a normal weight (73%). A positive correlation was found between breast development and component 1 and component 2, as well as a negative correlation between the breasts and component 3. In the boys, the development of genitals and pubic hair was positively correlated with component 2 and inversely correlated with component 3. It could therefore be concluded that there is a relationship between sexual maturation and the anthropometric and blood pressure indicators, which proved to be representative variables for cardiovascular risk in teenagers, even if not in their entirety.

Testicular volume and Tanner stage: determinant factors for testicular torsion

ABSTRACT Objective To assess testicular volumes and sexual maturation in patients with testicular torsion. Methods A retrospective analysis of consecutively treated patients with testicular torsion between 2016 and 2018. Age, pubic hair staging (Tanner), and by ultrasonography, volume of the unaffected testis (in cubic centimeters) were evaluated either immediately before surgery or at the first postoperative visit. Patients with previous testicular disease, such as cryptorchidism, or with no records of testicular volume were excluded. The analysis included descriptive statistics and Bayesian regression. Results We treated 149 patients during the study period, and 141 (94.6%, median age 17.3 years) met the inclusion criteria. Median testicular volume was 13.0cm3 (interquartile range of 10.5-15.2), with similar right and left volumes (12.9cm3versus 13.3cm3; p=0.94). Sixty-five (46.1%) patients were Tanner stage IV, 17 (12.1%) stage III, and 59 (41.8%) stage V. Conclusion In this study, we were able to estimate volumes of testicular torsion, which aggregated around late puberty values (13.0cm3 for the whole dataset, 12.2cm3 for patients <25 years), suggesting that testicular hypermobility, due to congenital anatomical abnormalities, remains quiescent until the organ reaches a critical volume, after which torsion becomes possible. These findings provide a tentative explanation for the disease's age distribution.

Isoflavones alter male and female fertility in different development windows.

Isoflavones are a group of secondary metabolites found in plants belonging to the class of phytoestrogens. These, because they have a chemical structure similar to the endogenous hormone 17ß-estradiol, act as endocrine disruptors over the different development window periods. This study aimed to evaluate male and female reproductive systems' responses when exposed to isoflavones during the development window. It is characterized as a bibliographic review, built after analyzing clinical and preclinical articles indexed in English, Portuguese, and Spanish published in the last ten years. The isoflavones, aglycone or glucosides, have essential therapeutic properties in the relief of postmenopausal symptoms in women, reduce the proliferation of cancers, in addition to being antioxidants. On the other hand, they can still behave in a similar way to 17ß-estradiol, binding to hormone receptors and acting as endocrine disruptors over the gestational period until pre-puberty, negatively affecting the development of the reproductive system. The effects on reproduction are not dose-response but are influenced by the type of isoflavone and period. There are variations in the serum concentration of hormones and action on their negative feedback on the hypothalamic-pituitary-testicular axis in males. Reproductive functions are also affected by spermatogenesis, such as decreased sperm count, lower reproductive performance, reduced litter size, low sperm production, and reduced seminal vesicle size. In females, puberty is reached later, irregular estrous cycle, reduced weight of the ovary, uterus, lower serum levels of estradiol and progesterone, reduced fertility, or interrupted fertility. At the end of the analysis of the selected publications, it can be concluded that despite the beneficial therapeutic effects in the face of pathologies, the unknown consumption of doses and types of isoflavones in food can damage the development and reproduction of individuals. Therefore, further studies must be carried out to elucidate the usual safe doses of the analyzed phytoestrogen. Greater control over insertion in foods targeted at pediatric consumers should be implemented until we have adequate safety.

Functions of the GABAergic system on serum LH concentrations in pre-pubertal Nellore heifers.

This study was conducted to evaluate the luteinizing hormone (LH) secretion pattern after gamma-aminobutyric acid (GABAA) antagonist to determine the effects of the GABAergic system on LH secretion during reproductive maturation in pre-pubertal Nellore heifers. Nellore heifers (n = 10) were administered a picrotoxin injection of 0.18 mg/kg, i.v. Blood samples were collected every 15 min for 3 h at different developmental stages (8, 10, 14 and 17 mo of age). Plasma concentrations of LH were quantified using an RIA (sensitivity of 0.04 ng/mL and CV of 15 %). There was an interaction between treatment and age (P = 0.034). Picrotoxin-treated heifers had lesser (P ≤  0.05) LH mean concentrations during a 3 h period at 10 and 17 mo of age compared to control heifers (P ≤  0.05). Comparing the period before and after Picrotoxin injection in the same animals, there was a 33 % decrease in LH concentration at 8 mo of age (P = 0.0165). These results indicate the GABAergic system has a stimulatory function in inducing LH secretion in pre-pubertal Nellore heifers. These findings corroborate previous results that GABA increases GnRH/LH secretion in other species during the pre-pubertal period.

Quantification of testosterone-dependent erythropoiesis during male puberty.

NEW FINDINGS: What is the central question of this study? To what extent does testosterone influence haemoglobin formation during male puberty? What is the main finding and its importance? In boys, testosterone might be responsible for about 65% of the increase in haemoglobin mass during puberty. The underlying mechanisms are assumed to be twofold: (i) indirectly, mediated by the increase in lean body mass, and (ii) directly by immediate testosterone effects on erythropoiesis. Thereby, an increase in testosterone of 1 ng/ml is associated with an increase in haemoglobin mass of ∼65 g. These processes are likely to determine endurance performance in adulthood. ABSTRACT: The amount of haemoglobin during puberty is related to endurance performance in adulthood. During male puberty, testosterone stimulates erythropoiesis and could therefore be used as a marker for later endurance performance. This cross-sectional study aimed to determine the relationship between serum testosterone concentration and haemoglobin mass (Hbmass) in both male and female children and adolescents and to evaluate the possible influences of altitude and training. Three-hundred and thirteen differentially trained boys and girls aged from 9 to 18 years and living at altitudes of 1000 and 2600 m above sea level entered the study. The stage of sexual maturation was determined according to the classification of Tanner. Testosterone was measured by ELISA. Hbmass was determined by CO-rebreathing. Haemoglobin concentration did not change during maturation in girls and was 11% higher during puberty in boys, while Hbmass was elevated by 33% in Tanner stage V compared to stage II in girls (498 ± 77 vs. 373 ± 88 g) and by 95% in boys (832 ± 143 vs. 428 ± 95 g). This difference can most likely be attributed to indirect testosterone influences through an increase in lean body mass (LBM) and to direct testosterone effects on erythropoiesis, which increase the Hbmass by ∼65 g per 1 ng/ml. Altitude and training statuses were not associated with testosterone, but with an increase in Hbmass (altitude by 1.1 g/kg LBM, training by 0.8 g/kg LBM). Changes in Hbmass are closely related to testosterone levels during male puberty. Further studies will show whether testosterone and Hbmass during childhood and adolescence can be used as diagnostic tools for endurance talents.

Atividade física na adolescência e maturidade sexual: uma revisão sistemática / Physical activity and adolescent sexual maturity: a systematic review

Resumo O objetivo é verificar a associação entre maturação sexual e atividade física na adolescência. Trata-se de um estudo de revisão sistemática elaborado a partir de artigos publicados entre 2008 a 2018 nas bases de dados Medline-PubMed, SciELO, Web of Science, Scopus, Lilacs e Adolec BVS. Utilizou-se os descritores e palavras-chave adolescente, maturação sexual, inquérito, questionário e atividade física, no idioma português e sua equivalência na língua inglesa e foram identificados 806 artigos. Após aplicação dos critérios de seleção foram incluídos 12 artigos. Maior nível da prática de atividade física foi observado em adolescentes em fase de maturação sexual inicial. A evolução do desenvolvimento maturacional sexual parece estar correlacionado à redução dos níveis de atividade física. Os achados não evidenciam um consenso sobre associação entre maturação sexual e nível de atividade física quanto à predisposição direta ou inversa da maturação sexual em relação ao nível de atividade física entre adolescentes. São necessárias mais pesquisas para compreender essa relação e possibilitar aos profissionais envolvidos com a saúde do adolescente agir efetivamente no combate à inatividade física.

Abstract The objective was to ve rify the association between sexual maturation and physical activity during adolescence. A systematic review of articles published between 2008 and 2018 was conducted using the following databases: PubMed/Medline, SciELO, Web of Science, Scopus, Lilacs, and BVS Adolec Brasil. The following descriptors and keywords were used in English and Portuguese: adolescent, sexual maturation, survey, questionnaire, and physical activity. The literature search retrieved 806 articles. Twelve articles were included after applying the selection criteria. Level of physical activity was highest in the initial stage of sexual maturation. Levels of physical activity appear to decrease with advancing sexual maturation status. There is no consensus about the association between sexual maturation and physical activity levels among adolescents within the literature reviewed by this study. Further research is needed to investigate whether this relationship exists and professionals involved in healthcare for adolescents should take effective steps to combat physical inactivity.

Diagnosis and management of precocious sexual maturation: an updated review.

The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. It is classified as central precocious puberty when premature maturation of the hypothalamic-pituitary-gonadal axis occurs, and as peripheral precocious puberty when there is excessive secretion of sex hormones, independent of gonadotropin secretion. Precocious sexual maturation is more common in girls, generally central precocious puberty of idiopathic origin. In boys, it tends to be linked to central nervous system abnormalities. Clinical evaluation should include a detailed history and physical examination, including anthropometric measurements, calculation of growth velocity, and evaluation of secondary sexual characteristics. The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. Hormonal assessment and imaging are required for diagnosis and identification of the etiology. Genetic testing should be considered if there is a family history of precocious puberty or other clinical features suggestive of a genetic syndrome. Long-acting gonadotropin-releasing hormone analogs are the standard of care for central precocious puberty management, while peripheral precocious puberty management depends on the etiology.Conclusion: The aim of this review is to address the epidemiology, etiology, clinical assessment, and management of precocious sexual maturation. What is Known: • The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. • Long-acting gonadotropin-releasing hormone agonist (GnRHa) is the standard of care for CPP management, and adequate hormone suppression results in the stabilization of pubertal progression, a decline in growth velocity, and a decrease in bone age advancement. What is New: • Most cases of precocious sexual maturation are gonadotropin-dependent and currently assumed to be idiopathic, but mutations in genes involved in pubertal development have been identified, such as MKRN3 and DLK1. • A different preparation of long-acting GnRHa is now available: 6-month subcutaneous injection.

Body phenotypes and sexual maturation in Brazilian and US adolescents: evidence for a change in BMI category.

OBJECTIVE: Our study aimed to describe body phenotypes (BP) estimated by multivariate analysis and their association with body mass. DESIGN: BP were defined based on demographic variables, anthropometric data (body mass, height, skinfolds and circumferences), body composition (phase angle measured by bioelectrical impedance analysis), biochemical parameters (TAG, glucose, total cholesterol ratio/LDL, Hb and sexual maturation (pubic hair and breasts or gonads). ANOVA was performed to verify the differences between skin colour and the stages of pubertal development, BP, body composition, anthropometric and biochemical variables. SETTING: Cities of São Paulo-SP, Piracicaba-SP and Florianópolis-SC from Brazil and the United States. PARTICIPANTS: 9269 adolescents aged between 10 and 15 years old. RESULTS: The composition of BP was similar in all surveys, which are: BP1 was composed by skinfolds, body mass and circumferences variables; BP2 by pubic hair, breast in girls or gonad in boys, height and age; BP3 by cholesterol, TAG and glucose; and BP4 by phase angle, Hb and glucose (negative loading). There was a strong correlation (r = 0·9, P < 0·001) between BP1 and BMI. CONCLUSION: We highlighted independence observed between biochemical parameters, anthropometry, body composition and sexual maturation. BP may support the calculation of scores for diagnosis of obesity based on anthropometric variables and overcome ambiguity in the isolated use of BMI.

Puberty in a sample of brazilian schoolboys: onset and anthropometric characteristics / Puberdade em uma amostra de meninos escolares brasileiros: início e características antropométricas

ABSTRACT Objective: To determine the age of puberty onset in boys and collect anthropometric data of participants at different puberty stages. Methods: This is a cross-sectional study that assessed 430 boys in a random sample representing 48,390 students from public and private schools from the city of Uberaba, Southeast Brazil. The inclusion criteria were males, aged between 5 and 18 years, and absence of previous diseases. Participants and their guardians filled a semistructured questionnaire with questions relevant to their and their parents' puberty. We set the significance at p<0.05 and calculated the 95% confidence intervals. Results: The mean age found in the puberty stage G2 was 11.2±1.8 (95% of participants in stage G2 were 9.2-13.4 years old). Pubarche data showed a mean of age of 11.0±1.6 years (95% of the participants experienced pubarche when they were 8.0-14.0 years old). When compared to the confidence intervals of two classical studies on the subject, our results showed a trend toward earlier pubarche. In addition, the mean age of this event in the children's parents was of 12.1±1.4 years, which was significantly higher than the age of the children's pubarche (p<0.001). Conclusions: These results indicate a secular decreasing trend in pubarche age and an earlier puberty onset. Considering these parameters, is important to design public policies aimed at preventing these early events.

RESUMO Objetivo: Determinar a idade em que a puberdade começa em meninos e coletar dados antropométricos de participantes em diferentes fases da puberdade. Métodos: Trata-se de um estudo transversal no qual foram avaliados 430 meninos, uma amostra aleatória representativa da população total de 48.390 estudantes de escolas públicas e particulares de Uberaba, Minas Gerais. Os critérios de inclusão foram: ser do sexo masculino, ter idade de 5 a 18 anos e ausência de doenças prévias. Os participantes e seus responsáveis preencheram um questionário semiestruturado com perguntas pertinentes à sua puberdade e à de seus pais. Os dados foram considerados significantes para p<0,05, e os intervalos de confiança calculados foram de 95%. Resultados: A média de idade encontrada no estágio G2 foi de 11,2±1,8 anos, sendo que 95% dos participantes em G2 tinham entre 9,2 a 13,4 anos. Quanto à pubarca, a média de idade foi de 11,0±1,6 anos, e 95% dos participantes apresentaram pubarca entre 8,0 e 14,0 anos. Quando tais resultados foram comparados aos intervalos de confiança de dois estudos clássicos sobre o tema, houve tendência à pubarca mais precoce. Além disso, a média de idade da pubarca nos pais das crianças foi de 12,1±1,4 anos, significantemente maior em relação à dos filhos (p<0,001). Conclusões: Os resultados indicam uma tendência secular em direção à diminuição da idade da pubarca e um possível início mais precoce da puberdade. É muito importante considerar esses parâmetros para estabelecer políticas públicas destinadas a prevenir esses eventos iniciais.

Gonadal maturation in Pseudoplatystoma metaense x Leiarius marmoratus hybrids, (Siluriformes: Pimelodidae) / Maduración gonadal en híbridos de Pseudoplatystoma metaense x Leiarius marmoratus (Siluriformes: Pimelodidae)

SUMMARY: Establishing guidelines for responsible management in fish production systems requires knowledge of the basic biology of the fish to be raised. The objective of this work was to determine the reproductive capacity of hybrids produced from the crossing of females of Pseudoplatystoma metaense with males of Leiarius marmoratus. Males presented a digitiform, unrestricted spermatogonial testicle containing caudal digits producing glycoproteins that do not form a seminal vesicle. It was possible to find free sperm in the lumen of the tubules and in the ducts. The ovary of the females was found to be saccular and synchronous with at least three groups of oocytes. In the first year of life, only oogonia up to previtellogenic oocytes (cortical alveolus 284.9 ± 35.7 mm in diameter) were found. After the second year vitellogenic oocytes 730 ± 3.78 mm in diameter were observed. The events of gonadal development of the hybrids indicate that they are gonochoric, synchronic animals. The maturation peaks in the high-water season, overlapping with the parental species. Therefore, the escape of hybrids from fish cultures to the rivers may increase the risk of crosses, gene introgression, or diminution of the reproductive capacity of the pure species.

RESUMEN: El establecimiento de pautas para la gestión responsable en los sistemas de producción de peces requiere el conocimiento de la biología básica de los peces a criar. El objetivo de este trabajo fue determinar la capacidad reproductiva de los híbridos producidos por el cruce de hembras de Pseudoplatystoma metaense con machos de Leiarius marmoratus. Los machos presentaron un testículo espermatogonial digital no restringido que contiene dígitos caudales que producen glucoproteínas que no forman una vesícula seminal. Fue posible encontrar esperma libre en la luz de los túbulos y en los conductos. Se encontró que el ovario de las hembras era sacular y sincrónico con al menos tres grupos de ovocitos. En el primer año de vida, solo se encontraron oogonia hasta ovocitos previtelogénicos (alvéolo cortical de 284,9 ± 35,7 mm de diámetro). Después del segundo año, se observaron ovocitos vitelogénicos de 730 ± 3,78 mm de diámetro. Los eventos de desarrollo gonadal de los híbridos indican que son animales sincrónicos gonocóricos. La maduración alcanza su punto máximo en la temporada de aguas altas, superponiéndose con las especies parentales. Por lo tanto, el escape de híbridos de cultivos de peces a los ríos puede aumentar el riesgo de cruces, introgresión genética o disminución de la capacidad reproductiva de las especies puras.

Clinical and Genetic Characterization of a Constitutional Delay of Growth and Puberty Cohort.

INTRODUCTION: Constitutional delay of growth and puberty (CDGP) is the most prevalent cause of delayed puberty in both sexes. Family history of delayed puberty (2 or more affected members in a family) has been evidenced in 50-75% of patients with CDGP and the inheritance is often consistent with autosomal dominant pattern, with or without complete penetrance. However, the molecular basis of CDGP is not completely understood. OBJECTIVE: To characterize the clinical and genetic features of a CDGP cohort. METHODS: Fifty-nine patients with CDGP (48 boys and 11 girls) underwent careful and long-term clinical evaluation. Genetic analysis was performed using a custom DNA target enrichment panel designed to capture 36 known and candidate genes implicated with pubertal development. RESULTS: All patients had spontaneous or induced pubertal development (transient hormonal therapy) prior to 18 years of age. The mean clinical follow-up time was 46 ± 28 months. Male predominance (81%), short stature (91%), and family history of delayed puberty (59%) were the main clinical features of this CDGP -cohort. Genetic analyses revealed 15 rare heterozygous missense variants in 15 patients with CDGP (25%) in seven different genes (IGSF10, GHSR, CHD7, SPRY4, WDR11, SEMA3A,and IL17RD). IGSF10 and GHSR were the most prevalent affected genes in this group. CONCLUSIONS: Several rare dominant variants in genes implicated with GnRH migration and metabolism were identified in a quarter of the patients with familial or sporadic CDGP, suggesting genetic heterogeneity in this frequent pediatric condition.

Fenótipos corporais na adolescência: é necessário ajustar o índice de massa corporal de acordo com os estágios de maturação sexual? / Body phenotypes in adolescence: is it necessary to adjust body mass index according to sexual maturation stages? / Fenotipos corporales en la adolescencia: ¿es necesario ajustar el índece de masa corporal de acuerdo a las fases de madurez sexual?

Resumo: O objetivo deste trabalho é analisar o efeito da maturação sexual sobre os fenótipos corporais gerados por análise multivariada do estado nutricional de adolescentes. Este é um estudo transversal e a amostra foi composta por 833 adolescentes escolares de 10 a 15 anos, selecionados por amostragem complexa em Piracicaba, São Paulo, Brasil. Os fenótipos corporais foram definidos por análise de componentes principais (ACP), a partir da idade, dados antropométricos (massa corporal, altura, dobras cutâneas e circunferência da cintura), composição corporal (ângulo de fase medido por impedância bioelétrica) e bioquímicos (triglicerídeos, glicose, razão colesterol total/LDL, hemoglobina). Os fenótipos corporais definidos foram: F1adiposidade caracterizada pela associação positiva com as variáveis dobras cutâneas, massa corporal e circunferência da cintura; F2crescimento caracterizado pela associação positiva entre altura e idade; F3bioquímico caracterizado pela associação positiva com razão colesterol/LDL, triglicerídeos e glicose; e F4metabólico caracterizado pela associação positiva com ângulo de fase, hemoglobina e negativa com glicose. Posteriormente, os fenótipos corporais foram considerados desfechos na análise dos efeitos mistos, incorporando o sexo no primeiro nível e as variáveis maturação sexual, idade, sexo e escore socioeconômico no segundo nível. Esta análise permitiu dimensionar o efeito da maturação sexual nos fenótipos corporais. Nossos resultados indicam que a maturação sexual apresentou variabilidade de explicação relevante somente sobre o fenótipo corporal que representa crescimento linear (altura e idade). Dessa forma, não é necessário ajustar as medidas antropométricas pela maturação sexual.

Abstract: This study aimed to analyze the effect of sexual maturation on body phenotypes, based on multivariate analysis of adolescents' nutritional status. This was a cross-sectional study with a sample of 833 adolescent schoolchildren 10 to 15 years of age, selected by complex sampling in Piracicaba, São Paulo State, Brazil. Body phenotypes were defined by principal components analysis (PCA), based on age, anthropometric data (body mass, height, skinfolds, and waist circumference), body composition (phase angle measured by bioelectrical impedance), and biochemical parameters (triglycerides, glucose, total cholesterol/LDL ratio, hemoglobin). Body phenotypes were classified as: P1adiposity characterized as positive association with skinfolds, body mass, and waist circumference; P2growth characterized as positive association between height and age; P3biochemical characterized as positive association with total cholesterol/LDL ratio, triglycerides, and glucose; and P4metabolic characterized as positive association with phase angle and hemoglobin and negative association with glucose. The phenotypes were later considered outcomes in the mixed effects analysis, incorporating sex at the first level and sexual maturation, age, sex, and socioeconomic score at the second level. This analysis allowed measuring the effect of sexual maturation on body phenotypes. Our results indicate that sexual maturation only a displayed relevant explanation of body phenotype that represents linear growth (height and age). Thus, it is not necessary to adjust anthropometric measures by sexual maturation.

Resumen: El objetivo de este trabajo es analizar el efecto de la madurez sexual sobre los fenotipos corporales generados por análisis multivariado del estado nutricional de adolescentes. Este es un estudio transversal, cuya la muestra estuvo compuesta por 833 adolescentes escolares de 10 a 15 años, seleccionados por muestra compleja en Piracicaba, São Paulo, Brasil. Los fenotipos corporales se definieron por análisis de componentes principales (ACP), a partir de la edad, datos antropométricos (masa corporal, altura, pliegues cutáneos y circunferencia de la cintura), composición corporal (ángulo de fase medido por impedancia bioeléctrica) y bioquímicos (triglicéridos, glucosa, razón colesterol total/LDL, hemoglobina). Los fenotipos corporales definidos fueron: F1adiposidad, caracterizada por la asociación positiva con las variables pliegues cutáneos, masa corporal y circunferencia de la cintura; F2crecimiento, caracterizado por la asociación positiva entre altura y edad; F3bioquímico, caracterizado por la asociación positiva con razón colesterol/LDL, triglicéridos y glucosa; y F4metabólico, caracterizado por la asociación positiva con ángulo de fase, hemoglobina y negativa con glucosa. Posteriormente, los fenotipos corporales fueron considerados resultados en el análisis de los efectos mixtos, incorporando el sexo en el primer nivel y las variables de madurez sexual, edad, sexo y marcador socioeconómico en el segundo nivel. Este análisis permitió dimensionar el efecto de la madurez sexual en los fenotipos corporales. Nuestros resultados indican que la madurez sexual presentó variabilidad de explicación relevante solamente sobre el fenotipo corporal que representa crecimiento lineal (altura y edad). De esta forma, no es necesario ajustar las medidas antropométricas por la madurez sexual.

The stretch-shortening cycle efficiency is dependent on the maturational stage / A eficiência do ciclo alongamento-encurtamento é dependente do estágio maturacional

Abstract Maturation interferes with physiological and mechanical aspects of muscle contraction. The aim of the present study was to compare the efficiency of the stretch-shortening cycle (SSC) between different maturation stages. One hundred forty six young people, with 72 boys and 74 girls, were recruited to participate in the study. Sexual maturation was measured and the group was stratified into adolescents (> 3 auto-tanner) and children (<2 auto-tanner). Squat jump (SJ) and countermovement jump (CMJ) performance were measured to measure reactive force (RF) capacity, eccentric utilization ratio (EUR) and pre-stretch augmentation (PSAP). The children did not present statistical difference between SJ and CMJ (t(55)= -1.93; ∆ = -0.61; 95% CI = -1.24 to -0.02; p = 0.058), while the adolescents presented higher performance of CMJ (t(89)= -12.28; ∆ = -2.44; 95% CI = -2.84 to -2.05; p <0.001). In addition, adolescents had higher RF performance (t(144)= 5.18; p <0.0001; 95% CI = 2.53 to 1.13), PSAP (t(144)= 4.38; p <0.0001; 95% CI = 14.00 to 5.29) and EUR (t(144)= 4.38; p <0.0001; 95% CI = 0.14 to 0.05). We conclude that more mature young people have better SSC utilization.

Resumo Maturação interfere em aspectos fisiológicos e mecânicos da contração muscular. O objetivo do estudo foi comparar a eficiência do ciclo alongamento-encurtamento (SSC) em diferentes estágios maturacionais. Cento e quarenta e seis jovens, sendo 72 meninos e 74 meninas, foram recrutados para participar do estudo. Maturação sexual foi mensurada e o grupo foi estratificado em adolescentes (≥ 3 e crianças (< estágio 2). Salto estático (SJ) e o salto contramovimento (CMJ) foram utilizados para mensurar a força reativa (RF), razão de utilização da excêntrica (EUR) e aumento do pré-estiramento (PSAP). As crianças não apresentaram diferença significante entre SJ e CMJ (t(55)= -1.93; ∆ = -0.61; 95% CI = -1.24 to -0.02; p = 0.058), Enquanto que os adolescentes apresentaram maior desempenho de CMJ (t(89)= -12.28; ∆ = -2.44; 95% CI = -2.84 to -2.05; p <0.001). Em adição, adolescentes apresentaram maior RF (t(144)= 5.18; p <0.0001; 95% CI = 2.53 to 1.13), PSAP (t(144)= 4.38; p <0.0001; 95% CI = 14.00 to 5.29) e EUR (t(144)= 4.38; p <0.0001; 95% CI = 0.14 to 0.05). Nós concluímos que jovens com mais maturados apresentam maior capacidade de utilização do SSC.

Tracking of cardiorespiratory fitness from childhood to early adolescence: moderation effect of somatic maturation / Tracking da aptidão cardiorrespiratória da infância para a adolescência: moderação pela maturação biológica

ABSTRACT Objective: To evaluate cardiorespiratory fitness' tracking from childhood to adolescence, as well as to test the moderation role of somatic maturation. Methods: Our sample was composed by 375 children (197 boys), with a baseline age between 7 and 10 years old. The children were followed-up over three years. Body mass and stature were measured as anthropometric indicators and were used to estimate maturity status through Moore's method. Cardiorespiratory fitness was evaluated through 9-minute running test. Body adiposity was estimated through the subcutaneous skinfold method, with measures of triceps and subscapular skinfolds and used as a covariate. Sample was categorized into tertiles. Thereafter, the Kappa (k) coefficient and Lin's concordance correlation coefficient (LCCC) tests were adopted to verify stability. Dummy variable in regression was used to test moderation effects. All analyses were conducted in Stata 14.0, adopting p<0.05. Results: Cardiorespiratory fitness presented a moderate to low tracking from childhood to adolescence (k=0.294; LCCC=0.458). Moreover, maturity status significantly moderated the association between cardiorespiratory fitness at childhood and adolescence (regardless of cohort and body adiposity) among boys (β=0.644; p=0.003) and role sample (β=0.184; p=0.020), but not girls (-0.217; p=0.413). Conclusions: Tracking of cardiorespiratory fitness from childhood to adolescence is moderate to low in both sexes. Moreover, maturity status moderated the relationship between cardiorespiratory fitness at baseline and in adolescence. A lower age at peak height velocity was associated to a greater cardiorespiratory fitness.

RESUMO Objetivo: Avaliar o tracking da aptidão cardiorrespiratória da infância à adolescência, bem como testar a via de moderação pela maturação somática. Métodos: A amostra foi composta de 375 crianças (197 meninos), com idades entre 7 e 10 anos na linha de base. Os sujeitos foram acompanhados por três anos. Massa corporal e estatura foram mensuradas como indicadores antropométricos e usadas para estimar a maturação somática pelo método de Moore. Aptidão cardiorrespiratória foi avaliada pelo teste de 9 minutos de corrida. Adiposidade corporal foi estimada pelo método de dobras subcutâneas, com medidas das dobras tricipital e subescapular, além de ter sido utilizada como covariável. A amostra foi categorizada em tercis, e então o coeficiente Kappa (k) e o coeficiente de correlação de concordância de Lin (LCCC) foram adotados para verificar estabilidade. Foram criadas variáveis dummy nas regressões para estimar o efeito de moderação. Todas as análises foram conduzidas no Stata 14.0, adotando p<0,05. Resultados: A aptidão cardiorrespiratória apresentou tracking baixo a moderado da infância para a adolescência (k=0,294; LCCC=0,458). Além disso, o status de maturação moderou significativamente a associação entre aptidão cardiorrespiratória na infância e adolescência (independentemente da coorte e adiposidade) em meninos (β=0,644; p<0,003) e na amostra total (β=0,184; p<0,020), mas não em meninas (-0,217; p=0,413). Conclusões: O tracking da aptidão cardiorrespiratória da infância à adolescência é baixo a moderado em ambos os sexos. Ainda, o estado maturacional moderou a associação entre aptidão cardiorrespiratória na infância e adolescência. Menor idade do pico de velocidade de crescimento foi associada à maior aptidão cardiorrespiratória.

Menarca y estado nutricional en niñas del periurbano de la ciudad de La Plata, Argentina / Menarche and nutritional status in peri-urban girls of La Plata city, Argentina

La menarca constituye un hito madurativo importante. A escala mundial ocurre, en promedio, a los 12,5 años y está sujeta a factores genéticos y/o ambientales. El objetivo fue analizar, en niñas residentes en la periferia urbana de La Plata: a) la edad mediana de menarca y b) si el estado nutricional y la distribución adiposa influyen en la edad de ocurrencia de menarca. Se evaluaron, durante los ciclos 2014-2017, en 657 niñas de 10-14 años: presencia(P)/ausencia(A) de menarca, peso, talla y pliegues subcutáneos tricipital y subescapular. Se determinaron: edad mediana de menarca (EM) según método status quo y regresión logística; estado nutricional -desnutrición, exceso ponderal y normonutrición- empleando como referencia y puntos de corte a la OMS; y distribución de adiposidad según índice subescapular/tricipital, considerando valores >1 indicativos de adiposidad centralizada. Se calcularon en general y por estado nutricional la EM y las prevalencias de ocurrencia comparándose mediante Chi2. La menarca estuvo presente en el 44,10% de las niñas con EM de 12,13 años. Alrededor del 54% de las niñas se mantuvo dentro de los límites normales (P: 41,20%; EM: 12,28 años) y el 45,70% estaban desnutridas; de estas 4,90% mostraron desnutrición debido a la baja estatura (P: 25,00%; MS: 13,40 años) y 40,80% tenían exceso de peso (P: 50,40%; MS: 11,78 años). El 32,72% de las niñas tenían adiposidad centralizada (P: 59,10%; EM: 11,79 años). Los resultados permiten concluir que el estado nutricional influye en la edad mediana de ocurrencia de la menarca, la cual es mayor en las niñas desnutridas y menor en las niñas con exceso ponderal. La disposición centralizada de la adiposidad favorece la presencia de menarca(AU)

Menarche is an important maturation milestone. It normally occurs at an average age of 12.5 years and is influenced by genetic and/or environmental factors. The aim of this study was to analyze in girls residing at suburbs of La Plata city a) the median age of menarche; b) if nutritional status and fat distribution have any influence in the age of menarche. During years 2014 to 2017, 657 girls aged between 10 and 14 years(y) were surveyed, determining: presence(P)/absence(A) of menarche, weight, height, and tricipital and subscapular skinfolds. It was measured: median age of menarche (MA) according to the status quo method and logistic regression; nutritional status -undernutrition, excess weight, and normonutrition- using WHO as a reference and their cut-off points; and the distribution of adiposity through the use of subscapular/tricipital index, considering values >1 an indicative of centralized adiposity. The median age of menarche was calculated both in the general sample and by nutritional status; general and age-prevalence of menarche were compared by Chi2. Menarche was present in 44.10% of the girls with MS of 12.13 years. About 54% of the population stayed within normal limits (P: 41.20%; MS: 12.28 years) and 45.70% were malnourished; of these 4.90% showed malnutrition due to short stature (P: 25.00 %; MS: 13.40 years) and 40.80% had weight excess (P: 50.40%; MS: 11.78 years). 32.72% of the girls had centralized adiposity (P: 59.10%; MS: 11.79 years). These results allow us to conclude that nutritional status influences the median age of menarche: it is higher in undernourished girls and lower in those with weight excess. Centralized disposition of adiposity promotes the presence of menarche(AU)

Influence of sexual maturation status on the relationship between body adiposity indicators and age: a cross-sectional study.

OBJECTIVES: To determine the influence of sexual maturation status on adiposity indicators of children and adolescents. RESULTS: 2412 individuals participated, 1285 (47.4%) males and 1408 (52.6%) females. There was moderate to weak correlation between age and adiposity indicators for both sexes. By analyzing the relationship between age and body fat indexes adjusted for Sexual Maturation Status, several changes were observed, mainly in girls. Precocious maturation was associated with increased adiposity indicators in girls, whereas late maturation was associated with decreased adiposity indicators in both sexes. Precocious maturation was associated with increased adiposity indicators in girls, whereas late maturation was associated with decreased adiposity indicators in both sexes.

Comparison of maturation and physical performance in basketball athletes of different playing positions / Comparação da maturação e desempenho físico em atletas de basquetebol de diferentes posições de jogo

Abstract The aim of this study was to compare the characteristics of somatic maturation, anthropometric and physical performance (vertical jump and aerobic power) in young basketball players of different playing positions (under 13 years) and analyze these relationships using Peak Height Velocity (PHV) as a measure of somatic maturation. For this, 26 male athletes were evaluated. Anthropometric variables were: body mass, standing and sitting height, and length of lower limbs. Maturation was determined by age at PHV. Physical performance was determined by lower limb power (counter movement jump - CMJ) and aerobic power (Intermittent Recovery Test) tests. MANOVA reported significant differences (p<0.05) among playing positions regarding variables Maturity Offset, estimated PHV age, standing height, sitting height, estimated leg length, body mass and Yo-Yo IR1. In addition, it was identified that point guards reached estimated PHV at later age than their peers who act as small forwards and centers. Regarding CMJ, no significant differences were identified among playing positions, but in relation to aerobic power, point guards and small forwards presented higher performance. These findings confirm that maturation has great effect on growth and physical performance measures and the estimated PHV age is an applicable tool in young athletes, mainly aiding professionals in structuring the teaching-learning- training process in this age group.

Resumo O objetivo do presente estudo foi comparar as características de maturação somática, antropométricas e desempenho físico entre as posições de jogo em jogadores de Basquetebol sub-13 e analisar estas relações utilizando o Pico de Velocidade de Crescimento (PVC) como uma medida da maturação somática. Para tanto, 26 atletas do sexo masculino foram avaliados. As variáveis antropométricas foram: massa corporal, estatura em pé e sentado e comprimento de membros inferiores. A maturação foi determinada pela idade do PVC. O desempenho físico foi através dos testes de potência de membros inferiores (salto com contra movimento - CMJ) e potência aeróbia (Yo-Yo IR1). A MANOVA reportou diferenças significativas (p<0,05) entre as posições em quadra nas variáveis Maturity Offset, idade do PVC estimado, estatura, altura sentado, comprimento de pernas estimado (CPE), massa corporal e Yo-Yo IR1. Além disso, foi identificado que os armadores alcançaram o PVC estimado, em uma idade mais tarde que seus companheiros que atuam como alas e pivôs. Em relação ao CMJ não foram identificadas diferenças significativas entre as posições, já em relação a potência aeróbia, os armadores e alas apresentaram desempenho significativo superior quando comparados aos pivôs. Estes achados confirmam que a maturação tem um grande efeito nas medidas de crescimento e desempenho físico e a determinação da idade estimada do PVC apresenta-se como uma ferramenta aplicável em jovens atletas, principalmente no auxílio de profissionais na estruturação do processo de ensino-aprendizagem-treinamento nesta faixa etária.

Soy protein supplement intake for 12 months has no effect on sexual maturation and may improve nutritional status in pre-pubertal children.

AIM: To evaluate the intake of a soy protein-based supplement (SPS) and its effects on the sexual maturation and nutritional status of prepubertal children who consumed it for a year. METHODS: Healthy children (n = 51) were recruited and randomly assigned to consume the lunch fruit juice with (n = 29) or without (n = 22) addition of 45 g of a commercial soy protein-based supplement (SPS) over 12 months. Nutritional assessment including anthropometry (bodyweight, height, triceps skinfold thickness, mid-upper arm circumference), body mass index (BMI), upper arm muscle area, arm muscle circumference, upper arm area, upper arm fat area data were derived from measures using usual procedures; age and gender-specific percentiles were used as reference. Sexual maturation was measured by Tanner stage. Isoflavones were quantified using liquid chromatography and tandem mass spectrometry. RESULTS: Height, BMI/age, weight/age and height/age were significantly different (P < 0.05) at 12 months between girls in the control and intervention groups. Statistically significant differences between groups by gender (P < 0.05) were found in boys in the control group for the triceps skinfold thickness and fat area. Nutritional status was adequate according to the World Health Organization parameters. On average, 0.130 mg/kg body weight/day of isoflavones were consumed by children, which did not show significant differences in their sexual maturation. CONCLUSION: Consumption of SPS for 12 months did not affect sexual maturation or the onset of puberty in prepubertal boys and girls; however, it may have induced an increase in height, BMI/age, height/age and weight/age of the girls, associated with variations in fat-free mass.