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1.
J Nepal Health Res Counc ; 17(4): 437-442, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32001845

RESUMO

BACKGROUND: Adolescence is a critical period and is associated with physical and psycho-social changes induced by puberty, which builds personality, behaviour, and future health of the adolescents. Thus, the aim of the study was to find out the knowledge and attitude regarding pubertal health of adolescence girls. METHODS: A descriptive cross sectional study was conducted in Bharatpur Metropolitan City's secondary level schools. A total of 183 adolescent girls were selected using probability simple random sampling from 5 schools out of total 43 schools which were also selected by simple random sampling technique. Data was collected by using structured self-administered questionnaire for knowledge and likert's scale was used for attitude regarding pubertal health. RESULTS: Study findings revealed that 61.4% of the students belonged to early adolescence (11-14) age group with the mean age 14.27±1.33 years. Majority (80.3%) had moderate level of knowledge and around half (48.6%) had positive attitude. Knowledge and attitude varied with the respondents' level of education (p=0.001), relation to sibling (p=0.013) and source of information by elder sister (p=0.022), teachers/school (p=0.001).Moderately positive correlation was found between knowledge and attitude which was highly significant (r=0.395, p<0.001). CONCLUSIONS: Majority of respondents had moderate level of knowledge and half of the respondent had positive attitude regarding pubertal health. Findings of the study emphasizes on improvement in education of adolescent girls which can help uplift health status and minimize vulnerability to health issues of pubertal health.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Maturidade Sexual/fisiologia , Adolescente , Criança , Informação de Saúde ao Consumidor/métodos , Estudos Transversais , Feminino , Humanos , Nepal , Fatores Socioeconômicos
2.
J Clin Res Pediatr Endocrinol ; 12(3): 269-274, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31948189

RESUMO

Objective: To determine internipple distance and internipple index in prepubertal Turkish girls. Methods: The internipple distance and chest circumference of 667 healthy prepubertal Turkish girls aged 6 to 11 years were measured in a school screening program in Düzce. Measurements were performed at the end of expiration with a standard non-stretch tape measure graduated in millimeters with the arms hanging in a relaxed position on the sides of the body. The internipple distance was measured between the centers of both nipples, and chest circumference was measured across the internipple line. The internipple index was calculated by dividing the internipple distance (cm) x100 by the chest circumference (cm). Age specific internipple index reference curves were constructed and smoothed with the Lambda-Mu-Sigma method. Mean and standard deviations of internipple distance and internipple index were calculated according to decimal ages. Results: Age was found to be positively correlated with internipple distance and chest circumference, while it was negatively correlated with internipple index. The reference values of internipple index, including 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles, and standard deviations were calculated for prepubertal girls. Conclusion: The reference ranges provided by this study might be helpful for the evaluation of syndromic cases by serving as normative data for internipple index in prepubertal girls aged 6-11 years in Turkey although ethnic differences may affect applicability to other countries.


Assuntos
Tamanho Corporal/fisiologia , Indicadores Básicos de Saúde , Tórax/crescimento & desenvolvimento , Fatores Etários , Criança , Desenvolvimento Infantil/fisiologia , Estudos Transversais , Feminino , Gráficos de Crescimento , Humanos , Mamilos , Puberdade/fisiologia , Valores de Referência , Maturidade Sexual/fisiologia , Tórax/anatomia & histologia , Turquia
3.
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
4.
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
5.
Nutrients ; 11(10)2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31635141

RESUMO

We designed an image-based dietary assessment tool called COFIT, which means "fit together" and pilot-tested it in the Taipei Puberty Longitudinal Study (TPLS). Children aged 6-17 years were invited to use COFIT over three days for recording all instances of eating in addition to maintaining written food records (FR). Spearman's correlation and Bland-Altman analysis were used to compare the intake of macronutrients and micronutrients estimated using the image-based dietary assessment and the FR method. Intra-class correlation coefficients were used to estimate reliability between dietitians. In the final analysis, 23 children (mean age: 10.47 ± 0.47 years) with complete data obtained using two dietary assessment methods were included. Reliability among dietitians was high. Most assessments of macronutrients and micronutrients revealed moderate correlations between the two methods (range: 0.27-0.94); moreover, no significant differences in nutrients assessments were observed between the two methods, except for energy and fat. The average difference in energy intake between the methods was 194 kcal/day. Most limits of agreement were within an acceptable range. The Bland-Altman plots showed robust agreement with minimum bias. The limitation was the small sample size and not dividing the population into children and teenagers since the two groups may have different food consumption habits. Overall, the results showed that the image-based assessment tool is suitable for assessing children's dietary intake of macronutrients and micronutrients during pubertal growth.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Inquéritos sobre Dietas , Avaliação Nutricional , Maturidade Sexual/fisiologia , Adolescente , Criança , Dieta , Comportamento Alimentar , Humanos , Projetos Piloto , Inquéritos e Questionários
6.
Horm Behav ; 111: 46-59, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30708031

RESUMO

Early life exposure to a low security setting, characterized by a scarcity of resources and limited food access, increases the risk for psychiatric illness and metabolic dysfunction. We utilized a translational rat model to mimic a low security environment and determined how this manipulation affected offspring behavior, metabolism, and puberty. Because food insecurity in humans is associated with reduced access to healthy food options the "low security" rat manipulation combined a Western diet with exposure to a limited bedding and nesting manipulation (WD-LB). In this setting, dams were provided with limited nesting materials during the pups' early life (P2-P10). This manipulation was contrasted with standard rodent caging (SD) and environmental enrichment (EE), to model "medium security" and "high security" environments, respectively. To determine if transitioning from a low to high security environment improved outcomes, some juvenile WD-LB offspring were exposed to EE. Maternal care was impacted by these environments such that EE dams engaged in high quality care when on the nest, but spent less time on the nest than SD dams. Although WD-LB dams excessively chased their tails, they were very attentive to their pups, perhaps to compensate for limited resources. Offspring exposed to WD-LB only displayed subtle changes in behavior. However, WD-LB exposure resulted in significant metabolic dysfunction characterized by increased body weight, precocious puberty and alterations in the hypothalamic kisspeptin system. These negative effects of WD-LB on puberty and weight regulation were mitigated by EE exposure. Collectively, these studies suggest that both compensatory maternal care and juvenile enrichment can reduce the impact of a low security environment. Moreover, they highlight how utilizing diverse models of resource (in)stability can reveal mechanisms that confer vulnerability and resilience to early life stress.


Assuntos
Abrigo para Animais , Comportamento Materno/fisiologia , Maturidade Sexual/fisiologia , Meio Social , Estresse Psicológico/complicações , Animais , Peso Corporal/fisiologia , Modelos Animais de Doenças , Feminino , Hipotálamo/metabolismo , Masculino , Comportamento Materno/psicologia , Estimulação Física/métodos , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/psicologia
7.
Pediatr Diabetes ; 20(4): 380-388, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30805996

RESUMO

BACKGROUND: From an evolutionary biology perspective, where growth and reproduction trade-off against longevity, we assessed the associations of growth from birth to puberty by phase with later glycemic indicators and any differences by sex. METHODS: In the population-representative Hong Kong Chinese "Children of 1997" birth cohort (n = 8327), the relation of initial size (weight-for-age z score (WAZ) at birth, length/height-for-age z score (LAZ) at 3 months or body-mass-index-for-age z score (BAZ) at 3 months based on the World Health Organization growth standards/references) and growth at different phases (WAZ gains from 0 to 2 and 2 to 8 years, LAZ or BAZ gains from 3 months to 3 years, 3 to 8 years and 8 to 14 years) with fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) at ~17.5 years, was assessed using adjusted partial least squares regression. Additional analyses further considered growth in late and early infancy. RESULTS: This study included 3276 of the cohort participants. Higher WAZ gain from 2 to 8 years, LAZ and BAZ gains from 3 to 8 years were consistently associated with higher FPG, adjusted for maternal and infant characteristics, family history of diabetes and household income. Also, higher BAZ gain from 3 to 8 years was associated with higher HbA1c. These associations did not differ by sex. CONCLUSIONS: Our findings suggest different mechanisms could underlie the pathogenesis of glucose intolerance. Factors that drive specific growth at different phases need to be evaluated to better inform child growth management for long-term health outcomes.


Assuntos
Glicemia/metabolismo , Desenvolvimento Infantil/fisiologia , Indicadores Básicos de Saúde , Parto/sangue , Maturidade Sexual/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Hong Kong/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Parto/fisiologia
8.
Orv Hetil ; 159(35): 1423-1432, 2018 Sep.
Artigo em Húngaro | MEDLINE | ID: mdl-30146904

RESUMO

The assessment of skeletal age is of utmost importance not only in the field of anthropology, forensic medicine, pediatrics, endocrinology but also in orthodontics and jaw orthopedics. Bone age refers to the individual's biological development which can differ within a relatively wide range for the same chronological age. Therefore, accurate assessment of skeletal maturity and pubertal growth plays an important role in establishing a diagnosis for certain diseases. In addition, it is essential for proper timing and success of treatments in many cases. Currently, there are many methods available to determine skeletal age and pubertal growth spurt. During growth, bones undergo significant changes, the sequence of which is strongly determined. These changes can be measured by various methods including radiological examinations. More specifically, these classical methods are often based on the radiological evaluation of morphological changes in the hand bones and cervical vertebrae. Methods based on dental development also exist to assess the biologic maturity of an individual. However, thanks to three-dimensional imaging techniques and molecular diagnostic methods, even more accurate tests can be performed to determine biological maturity. These modern methods rely on the information obtained from the cone-beam computer tomograph records and on the measurements of biomarkers present in different circulatory or other body fluids. The purpose of this summary is to provide an overview of the various classical and modern methods for the assessment of skeletal age that could aid us in many fields of science. Orv Hetil. 2018; 159(35): 1423-1432.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Antropometria/métodos , Desenvolvimento Ósseo/fisiologia , Maturidade Sexual/fisiologia , Adolescente , Desenvolvimento do Adolescente/fisiologia , Vértebras Cervicais/crescimento & desenvolvimento , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino
9.
Sci Total Environ ; 628-629: 1437-1445, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30045563

RESUMO

The effects of environmental lead exposure in the neuro-endocrine system have been shown to impact the maturation and tempo of puberty development in adolescents. In low and middle income countries very little is known regarding the detrimental health effects of childhood lead exposure with regard to the tempo of puberty development. To help address this gap in data, we examined the association between lead exposure and puberty progression in males and females. Study participants from the urban Birth to Twenty Plus (BT20+) birth cohort in Soweto-Johannesburg, South Africa with data for blood lead levels at age 13years, cord blood lead levels, pubic hair development and breast development in females, and pubic hair development and genital development in males, were included in this study. The sample comprised 1416 study participants (n=684 females). Pubertal development trajectory classes were defined using Latent Class Growth Analysis. Data were examined for (i) an association between cord blood lead levels and pubertal trajectory classes; and (ii) an association between blood lead levels at age 13years and pubertal trajectory classes. In females, there was an association between adolescent elevated blood lead levels (≥5µg/dL) and lower level of maturation at age 9years and slower progression of pubic hair and breast development (relative risk ratio (RRR)=0.45, p<0.0001; 95% CI (0.29-0.68)) and (RRR=0.46, p<0.01; 95% CI (0.27-0.77)), respectively. In males, elevated blood lead levels at birth were associated with slower tempo of pubic hair development (RRR=0.20, p<0.05). Findings from this study suggest a possible role for environmental lead in altering pubertal development in South African adolescents as shown by slower tempo of progression through the Tanner stages pubertal development in females and males. There were also gender-differences between the effects of prenatal and postnatal lead exposure during pubertal development.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Chumbo/sangue , Maturidade Sexual/efeitos dos fármacos , Adolescente , População Negra , Feminino , Cabelo , Humanos , Masculino , Fatores Sexuais , Maturidade Sexual/fisiologia , África do Sul
10.
Psychoneuroendocrinology ; 90: 76-84, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29454168

RESUMO

Puberty is a complex biopsychosocial process that can affect an array of psychiatric and medical disorders emerging in adolescence. Although the pubertal process is driven by neuroendocrine changes, few quantitative genetic studies have directly measured puberty-relevant hormones. Hair samples can now be assayed for accumulation of hormones over several months. In contrast to more conventional salivary measures, hair measures are not confounded by diurnal variation or hormonal reactivity. In an ethnically and socioeconomically diverse sample of 1286 child and adolescent twins and multiples from 672 unique families, we estimated genetic and environmental influences on hair concentrations of testosterone, DHEA, and progesterone across the period of 8-18 years of age. On average, male DHEA and testosterone were highly heritable, whereas female DHEA, progesterone, and puberty were largely influenced by environmental components. We identified sex-specific developmental windows of maximal heritability in each hormone. Peak heritability for DHEA occurred at approximately 10 years of age for males and females. Peak heritability for testosterone occurred at age 12.5 and 15.2 years for males and females, respectively. Peak heritability for male progesterone occurred at 11.2 years, while the heritability of female progesterone remained uniformly low. The identification of specific developmental windows when genetic signals for hormones are maximized has critical implications for well-informed models of hormone-behavior associations in childhood and adolescence.


Assuntos
Hormônios Gonadais/genética , Hormônios Gonadais/metabolismo , Cabelo/fisiologia , Puberdade/fisiologia , Adolescente , Criança , Desidroepiandrosterona/genética , Desidroepiandrosterona/metabolismo , Feminino , Interação Gene-Ambiente , Cabelo/química , Cabelo/crescimento & desenvolvimento , Cabelo/metabolismo , Humanos , Masculino , Método de Monte Carlo , Progesterona/genética , Progesterona/metabolismo , Puberdade/genética , Puberdade/metabolismo , Característica Quantitativa Herdável , Fatores Sexuais , Maturidade Sexual/genética , Maturidade Sexual/fisiologia , Testosterona/genética , Testosterona/metabolismo , Gêmeos/genética
11.
J Theor Biol ; 444: 83-92, 2018 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-29452173

RESUMO

Ectothermic and endothermic vertebrates differ not only in their source of body temperature (environment vs. metabolism), but also in growth patterns, in timing of sexual maturation within life, and energy intake functions. Here, we present a mathematical model applicable to ectothermic and endothermic vertebrates. It is designed to test whether differences in the timing of sexual maturation within an animal's life (age at which sexual maturity is reached vs. longevity) together with its ontogenetic gain in body mass (growth curve) can predict the energy intake throughout the animal's life (food intake curve) and can explain differences in energy partitioning (between growth, reproduction, heat production and maintenance, with the latter subsuming any other additional task requiring energy) between ectothermic and endothermic vertebrates. With our model we calculated from the growth curves and ages at which species reached sexual maturity energy intake functions and energy partitioning for five ectothermic and seven endothermic vertebrate species. We show that our model produces energy intake patterns and distributions as observed in ectothermic and endothermic species. Our results comply consistently with some empirical studies that in endothermic species, like birds and mammals, energy is used for heat production instead of growth, and with a hypothesis on the evolution of endothermy in amniotes published by us before. Our model offers an explanation on known differences in absolute energy intake between ectothermic fish and reptiles and endothermic birds and mammals. From a mathematical perspective, the model comes in two equivalent formulations, a differential and an integral one. It is derived from a discrete level approach, and it is shown to be well-posed and to attain a unique solution for (almost) every parameter set. Numerically, the integral formulation of the model is considered as an inverse problem with unknown parameters that are estimated using a series of empirical data.


Assuntos
Ingestão de Energia/fisiologia , Modelos Teóricos , Termogênese/fisiologia , Animais , Índice de Massa Corporal , Temperatura Corporal , Crescimento/fisiologia , Maturidade Sexual/fisiologia , Vertebrados
12.
Cancer Epidemiol Biomarkers Prev ; 26(12): 1714-1721, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28939588

RESUMO

Background: Higher socioeconomic position (SEP) has been associated with increased risk of breast cancer. Its relationship with earlier age of pubertal onset, a risk factor for breast cancer, is less clear.Methods: We studied the relationship of SEP to pubertal onset in a multiethnic cohort of 1,237 girls ages 6 to 8 years at baseline. Girls in three U.S. cities were followed for 5 to 8 years with annual clinical examinations from 2004 to 2012. SEP measures were examined for associations with pubertal onset, assessed by breast budding (thelarche) and pubic hair development (adrenarche). Analyses were conducted with accelerated failure time models using a Weibull distribution, with left, right, and interval censoring.Results: Higher body mass index percentage at entry to the study and black or Hispanic race/ethnicity were the strongest predictors of age at pubertal onset. An SEP index comprising household family income, mother's education, and home ownership was an independent predictor of thelarche in adjusted models for all girls together and for white and Latina, separately, but not black girls, and the relationship varied by study site. The SEP index was not related to adrenarche in adjusted models. Overall, girls from the lowest quintile of SEP entered puberty on average 6% earlier than girls from the highest quintile (time ratio = 0.94; 95% confidence interval 0.91-0.97) in adjusted models.Conclusions: Our results suggest that early-life SEP may influence the timing of pubertal development.Impact: Factors related to lower SEP in childhood can adversely affect early development in ways that may increase the risk of breast cancer. Cancer Epidemiol Biomarkers Prev; 26(12); 1714-21. ©2017 AACR.


Assuntos
Neoplasias da Mama/epidemiologia , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Classe Social , Adolescente , Fatores Etários , Índice de Massa Corporal , Mama/crescimento & desenvolvimento , Neoplasias da Mama/fisiopatologia , Feminino , Humanos , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
13.
Br J Sports Med ; 49(13): 852-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26084525

RESUMO

The search for talent is pervasive in youth sports. Selection/exclusion in many sports follows a maturity-related gradient largely during the interval of puberty and growth spurt. As such, there is emphasis on methods for assessing maturation. Commonly used methods for assessing status (skeletal age, secondary sex characteristics) and estimating timing (ages at peak height velocity (PHV) and menarche) in youth athletes and two relatively recent anthropometric (non-invasive) methods (status-percentage of predicted near adult height attained at observation, timing-predicted maturity offset/age at PHV) are described and evaluated. The latter methods need further validation with athletes. Currently available data on the maturity status and timing of youth athletes are subsequently summarised. Selection for sport and potential maturity-related correlates are then discussed in the context of talent development and associated models. Talent development from novice to elite is superimposed on a constantly changing base-the processes of physical growth, biological maturation and behavioural development, which occur simultaneously and interact with each other. The processes which are highly individualised also interact with the demands of a sport per se and with involved adults (coaches, trainers, administrators, parents/guardians).


Assuntos
Desenvolvimento do Adolescente/fisiologia , Esportes Juvenis/fisiologia , Adolescente , Determinação da Idade pelo Esqueleto/métodos , Aptidão/fisiologia , Criança , Feminino , Crescimento/fisiologia , Humanos , Masculino , Menarca/fisiologia , Desenvolvimento Musculoesquelético/fisiologia , Educação Física e Treinamento/métodos , Exame Físico/métodos , Puberdade/fisiologia , Maturidade Sexual/fisiologia
14.
Anthropol Anz ; 72(1): 1-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25779872

RESUMO

The inequalities among the socioeconomic strata in the Hungarian society increased during the last decades. Since the socioeconomic conditions play a decisive part in shaping the growth and maturation of children, our purpose was to study the body structure and the growth and maturation pattern of children living in deprived regions in Hungary. Our former analysis revealed that the prevalence of non-normal nutritional status was significantly higher in children and adolescents living in the seriously deprived regions of Hungary than the national reference values. The main purpose of the present study was to compare the sexual maturation pattern of pubertal children living in the deprived regions by comparing the timing of pubertal maturation events to the national reference values. Sexual maturity status of 711 girls and 790 boys (aged 10 - 16 years) living in the deprived small regions of Hungary was compared to the national reference values (Hungarian National Growth Study II). Sexual maturity status was estimated by the stages of pubic hair, axillary hair, breast and external genitalia development, as well as by the menarcheal and spermarcheal status, respectively. The median ages of being in the pubertal stages of the sexual characteristics, menarcheal and spermarcheal age were estimated by probit analysis. By comparing it to the national reference values, the timing of pubertal development in boys and girls living in the seriously deprived regions showed a 1 - 3-month shift toward older ages. However, the length of sexual maturation: the interval between the median ages of the first and last pubertal stages of sexual characteristics was similar in the subjects living in the regions of Hungary as the Hungarian reference values.


Assuntos
Pobreza/estatística & dados numéricos , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Adolescente , Antropologia Física , Criança , Feminino , Humanos , Hungria/epidemiologia , Masculino , Menarca , Caracteres Sexuais , Fatores Socioeconômicos
15.
Int J Sports Med ; 36(3): 234-40, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25429551

RESUMO

The purpose of the study was to examine the effect of age on short-term performance indicators applying multilevel regression modeling, and whether changes induced by age were affected by maturation. The study applied a mixed longitudinal approach with 8 measurement points over a period of 4 years. Anthropometry, predicted adult stature, countermovement jump, 15-m sprint and agility test from 38 under-11 young soccer players were considered. Early maturing players were 3% taller compared to late maturers. A substantial effect of age was present in all performance indicators (P<0.05). Parameters showed improvements in performance, even when accounting for interindividual variation in somatic maturity. Vertical jump tended to be stable in early maturers during the first year, presenting an exponential increase thereafter (16%, P<0.05). Additionally, early maturing boys had lower vertical jump scores but a substantial higher rate of development with age (3% per year). Performance tends to plateau during the first 3 years following the improvements in agility (9.1%, P<0.05). In the running tests, early maturers had better performances (19%, P<0.05), while a higher rate of improvement of 1% was observed for the late maturers. Young soccer players should be expected to have substantial improvements in short-term performance, influenced by independent variation between players in maturity status.


Assuntos
Desempenho Atlético/fisiologia , Maturidade Sexual/fisiologia , Futebol/fisiologia , Adolescente , Fatores Etários , Antropometria , Criança , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino
16.
Am J Public Health ; 104(12): 2290-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25320893

RESUMO

We explored the masculinity norms shaping transitions through puberty in rural and urban Tanzania and how these norms and their social-ecological context contribute to high-risk health behaviors. We conducted a qualitative case study of adolescent boys in and out of school in 2011 and 2012. Tanzania's social and economic development is reshaping the transition into young manhood. Adolescent boys are losing traditional mechanisms of pubertal guidance, and new meanings of manhood are arising from globalization. Traditional masculinity norms, including pressures to demonstrate virility and fertility, remain strong. Adolescent boys in modernizing Tanzania receive inadequate guidance on their burgeoning sexuality. Contradictory masculinity norms from family and society are shaping their sexual expectations, with implications for their engagement in unsafe sexual behaviors.


Assuntos
Masculinidade , Comportamento Sexual , Maturidade Sexual/fisiologia , Adolescente , Atitude Frente a Saúde , Humanos , Entrevistas como Assunto , Masculino , Puberdade/fisiologia , Pesquisa Qualitativa , Mudança Social , Meio Social , Tanzânia
17.
Vet Clin North Am Food Anim Pract ; 29(3): 493-516, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24182431

RESUMO

This article reviews the literature on breed, biological type, and breeding system and their impact on female fertility, especially as they relate to heifer development. The attributes of different breeding systems and their appropriate use is discussed. In addition, the extant and emerging selection tools that are available for replacement heifer selection are reviewed.


Assuntos
Cruzamento/métodos , Bovinos/genética , Bovinos/fisiologia , Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Animais , Cruzamento/economia , Bovinos/crescimento & desenvolvimento , Feminino , Indústria Alimentícia , Vigor Híbrido , Carne , Maturidade Sexual/fisiologia
18.
Indian J Gastroenterol ; 31(3): 130-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22711365

RESUMO

Delayed sexual maturation is a known complication of celiac disease (CD). There is paucity of data regarding the effect of gluten-free diet (GFD) on sexual maturity in patients with CD in India. We did a cross-sectional observational study to assess the sexual maturity in 30 adolescents with CD on GFD for at least 1 year, and evaluated factors which affect their sexual maturity. Sexual maturation was assessed using Tanner's stages of sexual development. All adolescents had completed 2 years of GFD and 53 % had completed 4 years of GFD. Sexual maturation was delayed in 30 %. Age at initiation of GFD was associated with attaining appropriate sexual maturity (p = 0.048). We conclude that delayed sexual maturation is not uncommon in adolescents with CD and may be corrected by early diagnosis and initiation of GFD.


Assuntos
Doença Celíaca/fisiopatologia , Dieta Livre de Glúten , Maturidade Sexual/fisiologia , Adolescente , Doença Celíaca/dietoterapia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino
19.
Folia Biol (Krakow) ; 60(3-4): 151-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23342910

RESUMO

We examined the sexual development and insemination capability of boars representing five breeds used at Polish sow insemination stations. The speed of attaining full breeding maturity by the boars and their insemination usefulness was assessed based on the results of experiments analysing age-related changes in the physical characteristics of the ejaculates. Directly after sampling, the ejaculates were analysed for the following physical parameters: ejaculate volume, sperm concentration and the percentage of progressively motile spermatozoa per ejaculate. The total number of spermatozoa in the ejaculates and the number of insemination doses obtained from one ejaculate were calculated using SYSTEM SUL v. 6.1 software. The sexual development of boars continues during insemination use, leading to improved ejaculatory performance. The physical parameters of the ejaculate change along with the age of the boar. The Duroc and Hampshire boars represent a pattern of sexual development that is different from that of the PLW, PL and Pietrain males, with an evident earlier termination of growth. The American boars (Duroc and Hampshire) acquire top ejaculatory performance approximately 6 months earlier.


Assuntos
Análise do Sêmen/veterinária , Maturidade Sexual/fisiologia , Suínos/fisiologia , Envelhecimento , Animais , Cruzamento , Ejaculação , Feminino , Inseminação Artificial , Masculino , Análise do Sêmen/normas
20.
Arch Latinoam Nutr ; 61(1): 36-44, 2011 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-22097288

RESUMO

The aim of this study was to analyze growth in relation to menarche in girls from two Argentinean urban populations. We performed a comparative-descriptive cross sectional study in 2474 schoolchildren between 8.0 and 16.9 years old from Santa Rosa (SR) and La Plata (LP) cities. We registered the presence of menarche and anthropometrics variables of body weight, total and sitting heights, arm circumference, triceps and subscapular skinfolds. Body mass index, subscapular/triceps index and muscle and fat arm areas were calculated. The study group was divided into 4 groups according to the city and menarche. The socio-environmental structured survey indicated significant differences between cities with these variables: tenure status, building materials and services, health care coverage, cash assistance, educational level and parents' occupation, therefore establishing a higher welfare in youngsters of SR. Menarche at a mean age of 12.7 years old was more prevalent in SR (40.6%) than in LP (33.7%) (c2 = 12.9; p < 0.01). The ANOVA indicated significant differences between cities in total and sitting heights and muscle area (p < 0.01), body weight and arm circumference (p < 0.05) which were generally held in the post hoc comparison by age in pre-menarche and post-menarche groups. The presence of a small body size at the expense of lowering in: total height, muscle area and leg length in LP youngsters, associated with a lower prevalence of menarche in this city, it would represents the adaptive cost of a lower welfare environment.


Assuntos
Composição Corporal , Crescimento/fisiologia , Menarca/fisiologia , Maturidade Sexual/fisiologia , Adolescente , Argentina , Criança , Estudos Transversais , Feminino , Humanos , Fatores Socioeconômicos , População Urbana
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