Recent changes in pubertal timing in healthy Danish boys

DEFF Research Database (Denmark)

Sørensen, K; Aksglæde, Lise; Petersen, Jørgen Holm

2010-01-01

In the 1990s, the American population-based study NHANES III renewed the focus on possible secular trends in male puberty. However, no conclusions could be made on pubertal onset due to the lack of compatible data.......In the 1990s, the American population-based study NHANES III renewed the focus on possible secular trends in male puberty. However, no conclusions could be made on pubertal onset due to the lack of compatible data....

Understanding the Link Between Pubertal Timing in Girls and the Development of Depressive Symptoms: The Role of Sexual Harassment.

Science.gov (United States)

Skoog, Therése; Bayram Özdemir, Sevgi; Stattin, Håkan

2016-02-01

The link between sexual maturation, or pubertal timing, in girls and adolescent depressive symptoms is well-documented, but the underlying processes remain unclear. We examined whether sexual harassment, which has previously been linked to both pubertal timing and depressive symptoms, mediates this link, using a two-wave longitudinal study including 454 girls in 7th (M age  = 13.42, SD = .53) and 8th grade (M age  = 14.42, SD = .55). Pubertal timing was linked to depressive symptoms in both age groups, and predicted an increase in depressive symptoms among the 7th graders. Sexual harassment significantly mediated the link between pubertal timing and depressive symptoms among the 7th, but not the 8th grade girls. Together, our findings suggest that one way to prevent depressive symptoms among early-maturing girls could be to address sexual harassment in preventive intervention in early adolescence.

Development and Lability in the Parent-Child Relationship During Adolescence: Associations With Pubertal Timing and Tempo

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Marceau, Kristine; Ram, Nilam; Susman, Elizabeth

2014-01-01

Adolescents' and parents' reactions to pubertal development are hypothesized to contribute to changes in family dynamics. Using 7-year longitudinal data from the NICHD-SECCYD (488 boys, 475 girls) we examined relations between pubertal development (timing, tempo) and trajectories (developmental change and year-to-year lability) of parent-child conflict and closeness from age 8.5 to 15.5 years. Changes were mostly characterized by year-to-year fluctuations – lability. Parent-child conflict increased and closeness decreased some with age. Pubertal timing and tempo were more consistently associated with lability in parent-child relationships than with long-term trends, although faster tempo was associated with steeper decreases in parent-child closeness. Findings provide a platform for examining how puberty contributes to both long-term and transient changes in adolescents' relationships and adjustment. PMID:26321856

Pubertal development timing in urban Chinese boys.

Science.gov (United States)

Ma, H-M; Chen, S-K; Chen, R-M; Zhu, C; Xiong, F; Li, T; Wang, W; Liu, G-L; Luo, X-P; Liu, L; Du, M-L

2011-10-01

We describe current pubertal development in healthy urban Chinese boys. A cross-sectional study of the pubertal development of 18,807 urban Chinese boys aged from 3.50 to 18.49years was conducted between 2003 and 2005. Testicular volume was evaluated with a Prader orchidometer. Pubic hair development was assessed according to the Tanner method. Data on spermarche were collected using the status quo method. Probit analysis was used to calculate the median age and 95% CI at different stages of testicular development, pubic hair development and spermarche. By age 9, 12.99% of the boys had a testicular volume of 4mL or greater. The median age of onset of puberty defined as the age at attainment of testicular volume of 4mL or greater was 10.55 (95% CI 10.27-10.79) years. The median age for onset of pubic hair development (PH(2) ) and spermarche was 12.78 (95%CI 12.67-12.89) years and 14.05 (95%CI 13.80-14.32) years, respectively. Pubertal onset in urban Chinese boys is earlier than currently used clinical norms but their pubic hair development occurs relatively late in comparison with the reported data from numerous other countries. There is also evidence of a secular trend towards an earlier age of spermarche since 1979 in Chinese urban boys. © 2011 The Authors. International Journal of Andrology © 2011 European Academy of Andrology.

Elite athletes and pubertal delay.

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Kapczuk, Karina

2017-10-01

Intensive physical training and participation in competitive sports during childhood and early adolescence may affect athletes' pubertal development. On the other hand, pubertal timing, early or late, may impact on an athlete selection for a particular sport. Genetic predisposition, training load, nutritional status and psychological stress determine athletes' pubertal timing. Athletes that practice esthetic sports, especially gymnasts, are predisposed to a delay in pubertal development. The growing evidence indicates that energy deficiency, not a systemic training per se, plays a crucial role in the pathogenesis of functional hypothalamic hypogonadism in female athletes. Metabolic and psychologic stress activate hypothalamic-pituitary-adrenal axis and suppress hypothalamic-pituitary-ovarian axis. Female athletes who do not begin secondary sexual development by the age of 14 or menstruation by the age of 16 warrant a comprehensive evaluation and a targeted treatment. Somatic growth and sexual maturation of elite female athletes are largely sport-specific since each sport favors a particular somatotype and requires a specific training. Chronic negative energy balance resulting from a systemic physical training and inadequate energy intake may delay pubertal development in elite athletes. Youth athletes, especially those engaged in competitive sports that emphasize prepubertal or lean appearance, are at risk of developing relative energy deficiency in sport associated with disordered eating or eating disorders. Management strategies should address the complex conditions underlying functional hypothalamic hypogonadism.

Sex 'n' drugs 'n' rock 'n' roll: the meaning and social consequences of pubertal timing.

Science.gov (United States)

Waylen, Andrea; Wolke, Dieter

2004-11-01

This is a brief review of the normal changes in adolescent behaviour and the interplay between biology and social factors that occur at and around puberty, in an attempt to explain when this transition may become problematic The onset of puberty is a biological marker for an individual's transition from a non-reproductive to a reproductive state. Adolescence is a normal developmental transition associated with clearly visible physical changes, reorganization and pruning of neuronal circuits in the brain and the occurrence of new behaviours and interests. It is a time when new life tasks (orientation towards peers of the other sex, romantic and sexual involvement and mastering an educational career) need to be mastered. Parent-child conflict increases and becomes more intense as the adolescent struggles for more independence while still requiring support. These normal changes can become problematic if biological and social expectations diverge e.g. entering puberty very early or very late. While early pubertal onset in boys is likely to have beneficial effects, in girls precocious pubertal timing may have a negative impact on body-image, affect (or emotional well-being) and sex-role expectations. Other individual biological predispositions and genetic endowment may interact with social factors (e.g. peers, parenting style, neighbourhood) making adolescence either an adaptive or a challenging transition. There is a lack of sufficiently large longitudinal studies that have been able to study this interaction between genetics, biology and social environment on adolescent development. The Avon Longitudinal Study of Parents and Children (ALSPAC) cohort provides a unique opportunity to investigate the impact of pubertal timing on social behaviour. Planned assessments and concepts are outlined.

Pubertal Timing and Early Sexual Intercourse in the Offspring of Teenage Mothers

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De Genna, Natacha M.; Larkby, Cynthia; Cornelius, Marie D.

2011-01-01

Early puberty is associated with stressful family environments, early sexual intercourse, and teenage pregnancy. We examined pubertal timing and sexual debut among the 14-year-old offspring of teenage mothers. Mothers (71% Black, 29% White) were recruited as pregnant teenagers (12-18 years old). Data were collected during pregnancy and when…

Role of amygdala kisspeptin in pubertal timing in female rats.

Directory of Open Access Journals (Sweden)

Daniel A Adekunbi

Full Text Available To investigate the mechanism by which maternal obesity disrupts reproductive function in offspring, we examined Kiss1 expression in the hypothalamic arcuate (ARC and anteroventral periventricular (AVPV nuclei, and posterodorsal medial amygdala (MePD of pre-pubertal and young adult offspring. Sprague-Dawley rats were fed either a standard or energy-dense diet for six weeks prior to mating and throughout pregnancy and lactation. Male and female offspring were weaned onto normal diet on postnatal day (pnd 21. Brains were collected on pnd 30 or 100 for qRT-PCR to determine Kiss1 mRNA levels. Maternal obesity increased Kiss1 mRNA expression in the MePD of pre-pubertal male and female offspring, whereas Kiss1 expression was not affected in the ARC or AVPV at this age. Maternal obesity reduced Kiss1 expression in all three brain regions of 3 month old female offspring, but only in MePD of males. The role of MePD kisspeptin on puberty, estrous cyclicity and preovulatory LH surges was assessed directly in a separate group of post-weanling and young adult female rats exposed to a normal diet throughout their life course. Bilateral intra-MePD cannulae connected to osmotic mini-pumps for delivery of kisspeptin receptor antagonist (Peptide 234 for 14 days were chronically implanted on pnd 21 or 100. Antagonism of MePD kisspeptin delayed puberty onset, disrupted estrous cyclicity and reduced the incidence of LH surges. These data show that the MePD plays a key role in pubertal timing and ovulation and that maternal obesity may act via amygdala kisspeptin signaling to influence reproductive function in the offspring.

Role Of Serum Lectin In Derangement Of PUBERTAL Timing In Thalassaemic Patients

International Nuclear Information System (INIS)

MOAWAD, A.T.; NASSAR, E.M.; EL-NASHAR, N.A.

2010-01-01

patients with delayed puberty. Serum leptin levels showed a negative correlation with ferritin levels and positive correlations with each of serum FSH, LH and testosterone in males and estradiol in females in both patients groups. It could be concluded that adipose tissue dysfunction, due to iron overload, could be considered as one of the endocrinopathies affecting thalassaemic patients. The consequent low leptin levels might be a cofactor in the derangement of pubertal timing observed in thalassaemic patients at puberty which necessitates newer protocols of treatment, correct blood transfusion and chelation therapy.

Peer and Individual Risk Factors in Adolescence Explaining the Relationship between Girls' Pubertal Timing and Teenage Childbearing

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Hendrick, C. Emily; Cance, Jessica Duncan; Maslowsky, Julie

2016-01-01

Girls with early pubertal timing are at elevated risk for teenage childbearing; however, the modifiable mechanisms driving this relationship are not well understood. The objective of the current study was to determine whether substance use, perceived peer substance use, and older first sexual partners mediate the relationships among girls' pubertal timing, sexual debut, and teenage childbearing. Data are from Waves 1 – 15 of the female cohort of the National Longitudinal Surveys of Youth 1997 (NLSY97), a nationwide, ongoing cohort study of U.S. men and women born between 1980 and 1984. The analytic sample (N=2,066) was 12-14 years old in 1997 and ethnically diverse (51% white, 27% black, 22% Latina). Using structural equation modeling, we found substance use in early adolescence and perceived peer substance use each partially mediated the relationships among girls' pubertal timing, sexual debut, and teenage childbearing. Our findings suggest early substance use behavior as one modifiable mechanism to be targeted by interventions aimed at preventing teenage childbearing among early developing girls. PMID:26769576

A Twin Study of Objective and Subjective Pubertal Timing and Peer Influence on Risk-Taking.

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Kretsch, Natalie; Mendle, Jane; Harden, K Paige

2016-03-01

The current study used a behavioral genetic design to test whether three measures of pubertal timing moderated peer influence on risk-taking in a sample of 248 female adolescent twin pairs ( M age =16.0, SD =1.5) from the National Longitudinal Study of Adolescent Health. Peer influence was operationalized as the quasi-causal association between girls' self-reported risk-taking and the risk-taking reported by their friends. Girls with earlier ages at menarche and who perceived themselves as more developed than peers were more susceptible to peer influence on risk-taking. However, age-standardized ratings of body changes did not moderate peer influence. This study highlights distinctions between multiple measures of pubertal timing, using an innovative synthesis of genetically informative data and peer nomination data.

Pubertal development, personality, and substance use: a 10-year longitudinal study from childhood to adolescence.

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Castellanos-Ryan, Natalie; Parent, Sophie; Vitaro, Frank; Tremblay, Richard E; Séguin, Jean R

2013-08-01

Most research linking early pubertal development to substance use has focused on the effects of pubertal timing (age at which a certain stage of pubertal development is reached or pubertal status at a particular age--related to the maturation disparity hypothesis), but little research has focused on pubertal tempo (rate of growth through pubertal stages--related to the maturation compression hypothesis). However, both timing and tempo have not only been identified as important components of pubertal development, with different predictors, but have also been shown to be independently associated with other adolescent psychopathologies. Using latent growth-curve modeling, this study examined how pubertal status at age 12 and pubertal tempo (between 11 and 13 years) related to substance use from 15 to 16 years in boys from low socioeconomic backgrounds (N = 871). Results showed that both pubertal status at age 12 and tempo were significant predictors of increased levels of substance use and problems in mid to late adolescence. In an attempt to identify mechanisms that may explain the association between pubertal development and substance use it was found that sensation seeking partially mediated the association between pubertal status at age 12 and substance use behaviors. Impulse control was found to moderate the association sensation seeking had with marijuana use frequency, with high sensation-seeking scores predicting higher marijuana use frequency only at low levels of impulse control. These findings highlight the importance of considering multiple sources of individual variability in the pubertal development of boys and provide support for both the maturational disparity and compression hypotheses. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Pubertal breast development in primary school girls in Sokoto, North ...

African Journals Online (AJOL)

Background. There is wide variation in normal pubertal timing among various populations. Objectives. To determine the mean age of pubertal stages of breast development and menarche, and the influence of nutrition and ethnicity on pubertal onset in primary school girls in Sokoto, North-Western Nigeria. Methods.

Sexual differentiation of human behavior: effects of prenatal and pubertal organizational hormones.

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Berenbaum, Sheri A; Beltz, Adriene M

2011-04-01

A key question concerns the extent to which sexual differentiation of human behavior is influenced by sex hormones present during sensitive periods of development (organizational effects), as occurs in other mammalian species. The most important sensitive period has been considered to be prenatal, but there is increasing attention to puberty as another organizational period, with the possibility of decreasing sensitivity to sex hormones across the pubertal transition. In this paper, we review evidence that sex hormones present during the prenatal and pubertal periods produce permanent changes to behavior. There is good evidence that exposure to high levels of androgens during prenatal development results in masculinization of activity and occupational interests, sexual orientation, and some spatial abilities; prenatal androgens have a smaller effect on gender identity, and there is insufficient information about androgen effects on sex-linked behavior problems. There is little good evidence regarding long-lasting behavioral effects of pubertal hormones, but there is some suggestion that they influence gender identity and perhaps some sex-linked forms of psychopathology, and there are many opportunities to study this issue. Copyright © 2011 Elsevier Inc. All rights reserved.

Sex variations in youth anxiety symptoms: effects of pubertal development and gender role orientation.

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Carter, Rona; Silverman, Wendy K; Jaccard, James

2011-01-01

This study evaluated whether pubertal development and gender role orientation (i.e., masculinity and femininity) can partially explain sex variations in youth anxiety symptoms among clinic-referred anxious youth (N = 175; ages 9-13 years; 74% Hispanic; 48% female). Using youth and parent ratings of youth anxiety symptoms, structural equation modeling results indicated that youth who reported being more advanced in their pubertal development reported high levels of femininity and anxiety symptoms. Youth who reported high levels of masculinity had low levels of anxiety symptoms as reported by both youths and parents. The estimated effects of pubertal development, femininity, and masculinity on youth and parent ratings of youth anxiety symptoms were not significantly moderated by biological sex. Pubertal development and gender role orientation appear to be important in explaining levels of youth anxiety symptoms among clinic-referred anxious youth.

Longitudinal Effects of Self-Report Pubertal Timing and Menarcheal Age on Adolescent Psychological and Behavioral Outcomes in Female Youths from Northern Taiwan.

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Lee, Chih-Ting; Tsai, Meng-Che; Lin, Chung-Ying; Strong, Carol

2017-08-01

Early puberty is linked to adverse developmental outcomes in adolescents in Western societies. However, little is known about this relationship in an East Asian context. In addition, whether the impact of subjective pubertal timing (PT) and menarcheal age (MA) on adolescent psychosocial development persists into early adulthood remains unclear and is worthy of investigation. A subset of data was retrieved from the Taiwan Youth Project, which recruited and followed a longitudinal cohort of 7 th - and 9 th -grade female Taiwanese students from 2000 to 2007. Subjective PT was defined using the Pubertal Developmental Scale (PDS), which mainly measures pubertal changes. MA was recalled by participants themselves. Various psychological and behavioral factors were recorded and measured until the age of 20, including the use of alcohol and cigarettes, psychological well-being, sexual activity, and socially problematic behaviors. A χ 2 test for linear-by-linear association and one-way analysis of variance followed by multivariate regression models were used to dissect the differential effects of PT and MA in the association with the outcome variables. In total, 1545 female participants with an average age of 14.5 (±1.1) years were deemed valid for analysis. Among them, 257 (16.6%) participants perceived themselves as having early PT, defined as more than 1 standard deviation above the mean PDS score, and 82 (5.3%) had early MA (occurring before the 4 th grade). In univariate analysis, participants with early PT had higher rates of smoking and sexual activity, and MA was not related to their psychobehavioral outcomes. After multivariate adjustment, only late PT was significantly correlated with lower amounts of cigarette smoking and sexual activity before the age of 20. Conceptual and actual pubertal developments may be differentially associated with psychobehavioral outcomes among young Taiwanese girls. Clinical attention should be given to adolescent self-perception of

Peer Exclusion During the Pubertal Transition: The Role of Social Competence.

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Carter, Rona; Halawah, Amira; Trinh, Sarah L

2018-01-01

For some youth, early puberty is accompanied by peer exclusion. Yet early developers may experience less peer exclusion if they have social competence, which would bolster their ability to develop and maintain positive relationships with their peers. Accordingly, the present study tests whether pubertal timing and tempo predicts decrements in children's social competence and whether decrements in social competence account for associations between puberty (timing and tempo) and peer exclusion over time. Longitudinal data were drawn from 1364 families (48% female; 76% White; M = 9.32 years, SD = .48, at Wave 3) who participated in Waves 3-5 (i.e., grades 4-6) of Phase III of the NICHD-SECCYD. The results from latent growth curve models indicated that earlier pubertal timing and more rapid pubertal tempo among girls were associated with high initial levels of peer exclusion. Moreover, mediation analyses revealed that early developers' susceptibility to peer exclusion was associated with their initial level of social competence. In boys, pubertal timing and tempo were not directly associated with peer exclusion; instead, indirect effects of pubertal timing on peer exclusion (intercept, slope) occurred through initial levels of social competence. On average, early developers' who had low levels of social competence also had high initial levels of peer exclusion but experienced decrements in peer exclusion over time. The association between the intercepts for puberty and peer exclusion and the slopes for social competence and peer exclusion were stronger for boys than girls. Overall, our findings suggest that early developers' susceptibility to and experiences of peer exclusion are associated with their development of social competence.

Effects of Di-(2-ethylhexyl Phthalate on the Hypothalamus–Uterus in Pubertal Female Rats

Directory of Open Access Journals (Sweden)

Te Liu

2016-11-01

Full Text Available The pollution of endocrine disruptors and its impact on human reproductive system have attracted much attention. Di-(2-ethylhexyl phthalate (DEHP, an environmental endocrine disruptor, is widely used in food packages, containers, medical supplies and children’s toys. It can cause diseases such as infertility, sexual precocity and uterine bleeding and thus arouse concerns from the society and scholars. The effect of DEHP on pubertal female reproductive system is still not well-studied. This study was to investigate the effects of DEHP on the hypothalamus–uterus in pubertal female rats, reveal the reproductive toxicity of DEHP on pubertal female rats and its mechanism, and provide scientific evidence for the evaluation of toxicity and toxic mechanism of DEHP on reproductive system. Forty-eight pubertal female rats were randomly divided into four groups and respectively administered via oral gavage 0, 250, 500, or 1000 mg/kg/d DEHP in 0.1 mL corn oil/20 g body weight for up to four weeks. Compared with control rats, the DEHP-treated rats showed: (1 higher gonadotropin-releasing hormone (GnRH level in the hypothalamus; (2 higher protein levels of GnRH in the hypothalamus; and (3 higher mRNA and protein levels of GnRH receptor (GnRHR in the uterus. Our data reveal that DEHP exposure may lead to a disruption in pubertal female rats and an imbalance of hypothalamus–uterus. Meanwhile, DEHP may, through the GnRH in the hypothalamus and its receptor on the uterus, lead to diseases of the uterus. DEHP may impose a negative influence on the development and functioning of the reproductive system in pubertal female rats.

Effects of Di-(2-ethylhexyl) Phthalate on the Hypothalamus–Uterus in Pubertal Female Rats

Science.gov (United States)

Liu, Te; Jia, Yiyang; Zhou, Liting; Wang, Qi; Sun, Di; Xu, Jin; Wu, Juan; Chen, Huaiji; Xu, Feng; Ye, Lin

2016-01-01

The pollution of endocrine disruptors and its impact on human reproductive system have attracted much attention. Di-(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, is widely used in food packages, containers, medical supplies and children’s toys. It can cause diseases such as infertility, sexual precocity and uterine bleeding and thus arouse concerns from the society and scholars. The effect of DEHP on pubertal female reproductive system is still not well-studied. This study was to investigate the effects of DEHP on the hypothalamus–uterus in pubertal female rats, reveal the reproductive toxicity of DEHP on pubertal female rats and its mechanism, and provide scientific evidence for the evaluation of toxicity and toxic mechanism of DEHP on reproductive system. Forty-eight pubertal female rats were randomly divided into four groups and respectively administered via oral gavage 0, 250, 500, or 1000 mg/kg/d DEHP in 0.1 mL corn oil/20 g body weight for up to four weeks. Compared with control rats, the DEHP-treated rats showed: (1) higher gonadotropin-releasing hormone (GnRH) level in the hypothalamus; (2) higher protein levels of GnRH in the hypothalamus; and (3) higher mRNA and protein levels of GnRH receptor (GnRHR) in the uterus. Our data reveal that DEHP exposure may lead to a disruption in pubertal female rats and an imbalance of hypothalamus–uterus. Meanwhile, DEHP may, through the GnRH in the hypothalamus and its receptor on the uterus, lead to diseases of the uterus. DEHP may impose a negative influence on the development and functioning of the reproductive system in pubertal female rats. PMID:27845755

Transitions in body and behavior: a meta-analytic study on the relationship between pubertal development and adolescent sexual behavior.

Science.gov (United States)

Baams, Laura; Dubas, Judith Semon; Overbeek, Geertjan; van Aken, Marcel A G

2015-06-01

The present meta-analysis studies the relations of pubertal timing and status with sexual behavior and sexual risk behavior among youth aged 10.5-22.4 years. We included biological sex, age, and ethnicity as potential moderators. Four databases were searched for studies (published between 1980 and 2012) on the relation between pubertal timing or status and sexual behavior. The outcomes were (1) sexual intercourse; (2) combined sexual behavior; and (3) risky sexual behavior. Earlier pubertal timing or more advanced pubertal status was related to earlier and more sexual behavior, and earlier pubertal timing was related to more risky sexual behavior. Further, the links between (1) pubertal status and combined sexual behavior and (2) pubertal timing and sexual intercourse status, combined sexual behavior, and risky sexual behavior were stronger for girls than boys. Most links between pubertal status, timing, and sexual behavior and sexual risk behavior were stronger for younger adolescents. Moderation by ethnicity did not yield consistent results. There was significant variation in results among studies that was not fully explained by differences in biological sex, age, and ethnicity. Future research is needed to identify moderators that explain the variation in effects and to design sexual health interventions for young adolescents. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

The value of shoe size for prediction of the timing of the pubertal growth spurt.

NARCIS (Netherlands)

Busscher, I.; Kingma, I.; Wapstra, F.H.; Bulstra, S.K.; Verkerke, G.J.; Veldhuizen, A.G.

2011-01-01

Background: Knowing the timing of the pubertal growth spurt of the spine, represented by sitting height, is essential for the prognosis and therapy of adolescent idiopathic scoliosis. There are several indicators that reflect growth or remaining growth of the patient. For example, distal body parts

Genome-wide association and longitudinal analyses reveal genetic loci linking pubertal height growth, pubertal timing and childhood adiposity

NARCIS (Netherlands)

Cousminer, Diana L.; Berry, Diane J.; Timpson, Nicholas J.; Ang, Wei; Thiering, Elisabeth; Byrne, Enda M.; Taal, H. Rob; Huikari, Ville; Bradfield, Jonathan P.; Kerkhof, Marjan; Groen-Blokhuis, Maria M.; Kreiner-Moller, Eskil; Marinelli, Marcella; Holst, Claus; Leinonen, Jaakko T.; Perry, John R. B.; Surakka, Ida; Pietilainen, Olli; Kettunen, Johannes; Anttila, Verneri; Kaakinen, Marika; Sovio, Ulla; Pouta, Anneli; Das, Shikta; Lagou, Vasiliki; Power, Chris; Prokopenko, Inga; Evans, David M.; Kemp, John P.; St Pourcain, Beate; Ring, Susan; Palotie, Aarno; Kajantie, Eero; Osmond, Clive; Lehtimaki, Terho; Viikari, Jorma S.; Kahonen, Mika; Warrington, Nicole M.; Lye, Stephen J.; Palmer, Lyle J.; Tiesler, Carla M. T.; Flexeder, Claudia; Montgomery, Grant W.; Medland, Sarah E.; Hofman, Albert; Hakonarson, Hakon; Guxens, Monica; Bartels, Meike; Salomaa, Veikko; Koppelman, Gerard H.

2013-01-01

The pubertal height growth spurt is a distinctive feature of childhood growth reflecting both the central onset of puberty and local growth factors. Although little is known about the underlying genetics, growth variability during puberty correlates with adult risks for hormone-dependent cancer and

Exposure to peer delinquency as a mediator between self-report pubertal timing and delinquency: A longitudinal study of mediation

Science.gov (United States)

Negriff, Sonya; Ji, Juye; Trickett, Penelope K.

2013-01-01

This study examined exposure to peer delinquency as a mediator between pubertal timing and self-reported delinquency longitudinally and whether this mediational model was moderated by either gender or maltreatment experience. Data were obtained from Time 1, 2, and 3 of a longitudinal study of maltreatment and development. At Time 1 the sample comprised 454 children aged 9–13 years. Analyses via structural equation modeling supported full mediation. Gender did not moderate this mediational relationship, but maltreatment experience did. The results show that early maturing males and females are both at risk for being exposed to peers that may draw them into delinquent behavior. Additionally, the mechanism linking early pubertal timing to delinquency differs depending on maltreatment experience. PMID:21262055

Effects of programmed physical activity on body composition in post-pubertal schoolchildren

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Edson dos Santos Farias

2015-04-01

Full Text Available OBJECTIVE: To assess body composition modifications in post-pubertal schoolchildren after practice of a physical activity program during one school year. METHODS: The sample consisted of 386 students aged between 15 and 17 years and divided into two groups: the study group (SG comprised 195 students and the control group (CG, 191. The SG was submitted to a physical activity program and the CG attended conventional physical education classes. Body composition was assessed using body mass index (BMI, percentage of body fat (%BF, fat mass (FM, and lean mass (LM. RESULTS: A positive effect of the physical activity program on body composition in the SG (p < 0.001 was observed, as well as on the interaction time x group in all the variables analyzed in both genders. A reduction in %BF (mean of differences = -5.58% and waist circumference (-2.33 cm, as well as an increase in LM (+2.05 kg were observed in the SG for both genders, whereas the opposite was observed in the CG. CONCLUSION: The practice of programmed physical activity promotes significant reduction of body fat in post-pubertal schoolchildren.

Maternal pre-pregnancy body mass index and pubertal development among sons

DEFF Research Database (Denmark)

Hounsgaard, M L; Håkonsen, L B; Vested, A

2014-01-01

Maternal overweight and obesity in pregnancy has been associated with earlier age of menarche in daughters as well as reduced semen quality in sons. We aimed at investigating pubertal development in sons born by mothers with a high body mass index (BMI). The study included 2522 sons of mothers...... indicators of pubertal development, results also indicated earlier pubertal development among sons of obese mothers. After excluding sons of underweight mothers in a subanalysis, we observed an inverse trend between maternal pre-pregnancy BMI and age at regular shaving, acne and first nocturnal emission....... In conclusion, maternal pre-pregnant obesity may be related to earlier timing of pubertal milestones among sons. More research, preferably based on prospectively collected information about pubertal development, is needed to draw firm conclusions....

Early adolescent boys’ exposure to Internet pornography: relationships to pubertal timing, sensation seeking, and academic performance

NARCIS (Netherlands)

Beyens, I.; Vandenbosch, L.; Eggermont, S.

2015-01-01

Research has demonstrated that adolescents regularly use Internet pornography. This two-wave panel study aimed to test an integrative model in early adolescent boys (Mage = 14.10; N = 325) that (a) explains their exposure to Internet pornography by looking at relationships with pubertal timing and

Pubertal Timing and Mexican-Origin Girls' Internalizing and Externalizing Symptoms: The Influence of Harsh Parenting

Science.gov (United States)

Deardorff, Julianna; Cham, Heining; Gonzales, Nancy A.; White, Rebecca M. B.; Tein, Jenn-Yun; Wong, Jessie J.; Roosa, Mark W.

2013-01-01

Early-maturing girls are at risk for internalizing and externalizing problems. Research concerning pubertal timing and mental health among Mexican Americans or the influence of parenting behaviors on these relations has been scarce. This study addressed these gaps. This was a prospective examination of 362 Mexican-origin girls and their mothers in…

Recent changes in pubertal timing in healthy Danish boys: associations with body mass index

DEFF Research Database (Denmark)

Sørensen, Kaspar; Aksglaede, Lise; Petersen, Jørgen Holm

2010-01-01

In the 1990s, the American population-based study NHANES III renewed the focus on possible secular trends in male puberty. However, no conclusions could be made on pubertal onset due to the lack of compatible data.......In the 1990s, the American population-based study NHANES III renewed the focus on possible secular trends in male puberty. However, no conclusions could be made on pubertal onset due to the lack of compatible data....

[Pubertal growth of 1,453 healthy children according to age at pubertal growth spurt onset. The Barcelona longitudinal growth study].

Science.gov (United States)

Carrascosa, Antonio; Yeste, Diego; Moreno-Galdó, Antonio; Gussinyé, Miquel; Ferrández, Ángel; Clemente, María; Fernández-Cancio, Mónica

2018-02-20

Pubertal growth pattern differs according to age at pubertal growth spurt onset which occurs over a five years period (girls: 8-13 years, boys: 10-15 years). The need for more than one pubertal reference pattern has been proposed. We aimed to obtain five 1-year-age-interval pubertal patterns. Longitudinal (6 years of age-adult height) growth study of 1,453 healthy children to evaluate height-for-age, growth velocity-for-age and weight-for-age values. According to age at pubertal growth spurt onset girls were considered: very-early matures (8-9 years, n=119), early matures (9-10 years, n=157), intermediate matures (10-11 years, n=238), late matures (11-12 years, n=127) and very-late matures (12-13 years, n=102), and boys: very-early matures (10-11 years, n=110), early matures (11-12 years, n=139), intermediate matures (12-13 years, n=225), late matures (13-14 years, n=133) and very-late matures (14-15 years, n=103). Age at menarche and growth up to adult height were recorded. In both sexes, statistically-significant (P<.0001) and clinically-pertinent differences in pubertal growth pattern (mean height-for-age, mean growth velocity-for-age and mean pubertal height gain, values) were found among the five pubertal maturity groups and between each group and the whole population, despite similar adult height values. The same occurred for age at menarche and growth from menarche to adult height (P<.05). In both sexes, pubertal growth spurt onset is a critical milestone determining pubertal growth and sexual development. The contribution of our data to better clinical evaluation of growth according to the pubertal maturity tempo of each child will obviate the mistakes made when only one pubertal growth reference is used. Copyright © 2018. Publicado por Elsevier España, S.L.U.

Early Adolescent Boys' Exposure to Internet Pornography: Relationships to Pubertal Timing, Sensation Seeking, and Academic Performance

Science.gov (United States)

Beyens, Ine; Vandenbosch, Laura; Eggermont, Steven

2015-01-01

Research has demonstrated that adolescents regularly use Internet pornography. This two-wave panel study aimed to test an integrative model in early adolescent boys (M[subscript age] = 14.10; N = 325) that (a) explains their exposure to Internet pornography by looking at relationships with pubertal timing and sensation seeking, and (b) explores…

Subjective Age in Early Adolescence: Relationships with Chronological Age, Pubertal Timing, Desired Age, and Problem Behaviors

Science.gov (United States)

Hubley, Anita M.; Arim, Rubab G.

2012-01-01

Subjective age generally refers to the age that one feels. In a cross-sectional questionnaire study of 245 adolescents ages 10-14 years, we examined (a) whether, and when, a cross-over in subjective age occurs, (b) differences in subjective age among pubertal timing groups, (c) correlations between subjective age and each of desired age and five…

Adolescents' increasing stress response to social evaluation: pubertal effects on cortisol and alpha-amylase during public speaking.

Science.gov (United States)

van den Bos, Esther; de Rooij, Mark; Miers, Anne C; Bokhorst, Caroline L; Westenberg, P Michiel

2014-01-01

Stress responses to social evaluation are thought to increase during adolescence, which may be due to pubertal maturation. However, empirical evidence is scarce. This study is the first to investigate the relation between pubertal development and biological responses to a social-evaluative stressor longitudinally. Participants performed the Leiden Public Speaking Task twice, with a 2-year interval (N = 217; age at Time 1: 8-17 years). The results support an increase in sensitivity to social evaluation during adolescence. The overall cortisol and alpha-amylase responses increased-both between and within participants-and were more strongly related to self-reported pubertal development than to age. The cortisol response shifted from speech delivery toward anticipation. The alpha-amylase response increased in both phases. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

Validity of self-assessment of pubertal maturation

DEFF Research Database (Denmark)

Rasmussen, Anna; Wohlfahrt-Veje, Christine; Tefre de Renzy-Martin, Katrine

2015-01-01

BACKGROUND AND OBJECTIVES: Studies of adolescents often use self-assessment of pubertal maturation, the reliability of which has shown conflicting results. We aimed to examine the reliability of child and parent assessments of healthy boys and girls. METHODS: A total of 898 children (418 girls, 480...... overestimated older than their peers who made correct assessments. Girls and their parents tended to underestimate, whereas boys overestimated their pubertal stage. CONCLUSIONS: Pubertal assessment by the child or the parents is not a reliable measure of exact pubertal staging and should be augmented...

Pubertal development in ICSI children

NARCIS (Netherlands)

Belva, F.; Roelants, M.; Painter, R.; Bonduelle, M.; Devroey, P.; de Schepper, J.

2012-01-01

To date, information on the pubertal development of adolescents born after ICSI is scarce, since the very first cohort is only now reaching young adulthood. In this study, pubertal development at the age of 14 was characterized in a longitudinally followed cohort of ICSI-conceived teenagers and

The duration of pubertal growth peak among three skeletal classes

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Waqar Jeelani

Full Text Available ABSTRACT Introduction: Pubertal growth peak is closely associated with a rapid increase in mandibular length and offers a wide range of therapeutic modifiability. Objective: The aim of the present study was to determine and compare the mean ages of onset and duration of pubertal growth peak among three skeletal classes. Methods: A retrospective cross-sectional study was conducted using lateral cephalograms of 230 subjects with growth potential (110 males, 120 females. Subjects were categorized into three classes (Class I = 81, Class II = 82, Class III = 67, according to the sagittal relationship established between the maxilla and the mandible. The cervical vertebral maturation stage was recorded by means of Baccetti's method. The mean ages at CS3 and CS4 and the CS3-CS4 age interval were compared between boys and girls and among three skeletal classes. Results: Pubertal growth peak occurred on average four months earlier in girls than boys (p = 0.050. The average duration of pubertal growth peak was 11 months in Class I, seven months in Class II and 17 months in Class III subjects. Interclass differences were highly significant (Cohen's d > 0.08. However, no significant difference was found in the timing of pubertal growth peak onset among three skeletal classes (p = 0.126 in boys, p = 0.262 in girls. Conclusions: Girls enter pubertal growth peak on average four months earlier than boys. Moreover, the duration of pubertal growth peak is on average four months shorter in Class II and six months longer in Class III subjects as compared to Class I subjects.

Pubertal development in Danish children

DEFF Research Database (Denmark)

Juul, A; Teilmann, G; Scheike, Thomas Harder

2006-01-01

.0012). In Danish boys we found that age at genital stage 2 (G2) was 11.83 years. Both sexes were significantly taller compared with data from 1964, but timing of pubertal maturation seemed unaltered. Finally, puberty occurred much later in Denmark compared with recent data from USA. We could not detect any...

Nutrition and pubertal development

OpenAIRE

Soliman, Ashraf; De Sanctis, Vincenzo; Elalaily, Rania

2014-01-01

Nutrition is one of the most important factors affecting pubertal development. Puberty entails a progressive nonlinear process starting from prepubescent to full sexual maturity through the interaction and cooperation of biological, physical, and psychological changes. Consuming an adequate and balanced healthy diet during all phases of growth (infancy, childhood and puberty) appears necessary both for proper growth and normal pubertal development. Girls begin puberty at an earlier age compar...

Pubertal development in healthy children is mirrored by DNA methylation patterns in peripheral blood

DEFF Research Database (Denmark)

Almstrup, Kristian; Johansen, Marie Lindhardt; Busch, Alexander S.

2016-01-01

Puberty marks numerous physiological processes which are initiated by central activation of the hypothalamic–pituitary–gonadal axis, followed by development of secondary sexual characteristics. To a large extent, pubertal timing is heritable, but current knowledge of genetic polymorphismsonly...... explains few months in the large inter-individual variation in the timing of puberty. We have analysed longitudinal genome-wide changes in DNA methylation in peripheral blood samples (n = 102) obtained from 51 healthy children before and after pubertal onset. We show that changes in single methylation...... sites are tightly associated with physiological pubertal transition and altered reproductive hormone levels. These methylation sites cluster in and around genes enriched for biological functions related to pubertal development. Importantly, we identified that methylation of the genomic region containing...

Pubertal changes in emotional information processing: pupillary, behavioral, and subjective evidence during emotional word identification.

Science.gov (United States)

Silk, Jennifer S; Siegle, Greg J; Whalen, Diana J; Ostapenko, Laura J; Ladouceur, Cecile D; Dahl, Ronald E

2009-01-01

This study investigated pupillary and behavioral responses to an emotional word valence identification paradigm among 32 pre-/early pubertal and 34 mid-/late pubertal typically developing children and adolescents. Participants were asked to identify the valence of positive, negative, and neutral words while pupil dilation was assessed using an eyetracker. Mid-/late pubertal children showed greater peak pupillary reactivity to words presented during the emotional word identification task than pre-/early pubertal children, regardless of word valence. Mid-/late pubertal children also showed smaller sustained pupil dilation than pre-/early pubertal children after the word was no longer on screen. These findings were replicated controlling for participants' age. In addition, mid-/late pubertal children had faster reaction times to all words, and rated themselves as more emotional during their laboratory visit compared to pre-/early pubertal children. Greater recall of emotional words following the task was associated with mid-/late pubertal status, and greater recall of emotional words was also associated with higher peak pupil dilation. These results provide physiological, behavioral, and subjective evidence consistent with a model of puberty-specific changes in neurobehavioral systems underpinning emotional reactivity.

The longitudinal effects of physical activity and dietary calcium on bone mass accrual across stages of pubertal development.

Science.gov (United States)

Lappe, Joan M; Watson, Patrice; Gilsanz, Vicente; Hangartner, Thomas; Kalkwarf, Heidi J; Oberfield, Sharon; Shepherd, John; Winer, Karen K; Zemel, Babette

2015-01-01

Childhood and adolescence are critical periods of bone mineral content (BMC) accrual that may have long-term consequences for osteoporosis in adulthood. Adequate dietary calcium intake and weight-bearing physical activity are important for maximizing BMC accrual. However, the relative effects of physical activity and dietary calcium on BMC accrual throughout the continuum of pubertal development in childhood remains unclear. The purpose of this study was to determine the effects of self-reported dietary calcium intake and weight-bearing physical activity on bone mass accrual across the five stages of pubertal development in a large, diverse cohort of US children and adolescents. The Bone Mineral Density in Childhood study was a mixed longitudinal study with 7393 observations on 1743 subjects. Annually, we measured BMC by dual-energy X-ray absorptiometry (DXA), physical activity and calcium intake by questionnaire, and pubertal development (Tanner stage) by examination for up to 7 years. Mixed-effects regression models were used to assess physical activity and calcium intake effects on BMC accrual at each Tanner stage. We found that self-reported weight-bearing physical activity contributed to significantly greater BMC accrual in both sexes and racial subgroups (black and nonblack). In nonblack males, the magnitude of the activity effect on total body BMC accrual varied among Tanner stages after adjustment for calcium intake; the greatest difference between high- and low-activity boys was in Tanner stage 3. Calcium intake had a significant effect on bone accrual only in nonblack girls. This effect was not significantly different among Tanner stages. Our findings do not support differential effects of physical activity or calcium intake on bone mass accrual according to maturational stage. The study demonstrated significant longitudinal effects of weight-bearing physical activity on bone mass accrual through all stages of pubertal development. © 2014 American

Nutrition and pubertal development

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Ashraf Soliman

2014-01-01

Full Text Available Nutrition is one of the most important factors affecting pubertal development. Puberty entails a progressive nonlinear process starting from prepubescent to full sexual maturity through the interaction and cooperation of biological, physical, and psychological changes. Consuming an adequate and balanced healthy diet during all phases of growth (infancy, childhood and puberty appears necessary both for proper growth and normal pubertal development. Girls begin puberty at an earlier age compared to past decades. Excessive eating of many processed, high-fat foods, may be the cause of this phenomenon. Overweight or obese children are more likely to enter puberty early. Some evidence suggests that obesity can accelerate the onset of puberty in girls and may delay the onset of puberty in boys. Moreover, the progression of puberty is affected by nutrition. On the other hand, puberty triggers a growth spurt, which increases nutritional needs including macro and micronutrients. Increased caloric, protein, iron, calcium, zinc and folate needs have to be provided during this critical period of rapid growth. Severe primary or secondary malnutrition also can delay the onset and progression of puberty. The higher incidence of anorexia nervosa and bulimia in adolescents imposes a nutritional risk on pubertal development. Moreover, many environmental endocrine disruptors (EDs have been identified that can significantly impair the normal course of puberty. This mini-review sums up some important findings in this important complex that link nutrition and pubertal development.

Pubertal Onset in Apparently Healthy Indian Boys and Impact of Obesity.

Science.gov (United States)

Surana, Vineet; Dabas, Aashima; Khadgawat, Rajesh; Marwaha, Raman Kumar; Sreenivas, V; Ganie, M Ashraf; Gupta, Nandita; Mehan, Neena

2017-01-01

Primary - to determine the age of pubertal onset in Indian boys. Secondary - (a) to assess the impact of obesity on pubertal timing, (b) to assess the relationship between gonadotropins and puberty. Cross-sectional. General community-seven schools across New Delhi. Random sample of 1306 school boys, aged 6-17 years. Anthropometric measurement for weight and height and pubertal staging was performed for all subjects. Body mass index (BMI) was calculated to define overweight/obesity. Serum luteinizing hormone (LH), follicle stimulating hormone, and serum testosterone were measured in every sixth subject. Age at pubertal onset-testicular volume ≥4 mL (gonadarche) and pubic hair Stage II. Median age of attaining gonadarche and pubarche was 10.41 years (95% confidence interval [CI]: 10.2-10.6 years) and 13.60 (95% CI: 13.3-14.0 years), respectively. No significant difference in the age of attainment of gonadarche was observed in boys with normal or raised BMI, though pubarche occurred 8 months earlier in the latter group. Serum gonadotropins and testosterone increased with increasing stages of puberty but were unaffected by BMI. Serum LH level of 1.02 mIU/mL and testosterone level of >0.14 ng/mL showed the best prediction for pubertal onset. The study establishes a secular trend of the age of onset of puberty in Indian boys. Pubarche occurred earlier in overweight/obese boys. The cutoff levels of serum LH and testosterone for prediction of pubertal onset have been established.

Forty years trends in timing of pubertal growth spurt in 157,000 Danish school children

DEFF Research Database (Denmark)

Aksglæde, Lise; Olsen, Lina Wøhlk; Sørensen, Thorkild I.A.

2008-01-01

to 1969 who attended primary school in the Copenhagen Municipality. 135,223 girls and 21,612 boys fulfilled the criteria for determining age at OGS and age at PHV. These physiological events were used as markers of pubertal development in our computerized method in order to evaluate any secular trends...... in pubertal maturation during the study period (year of birth 1930 to 1969). In this period, age at OGS declined statistically significantly by 0.2 and 0.4 years in girls and boys, respectively, whereas age at PHV declined statistically significantly by 0.5 and 0.3 years in girls and boys, respectively...

Reproductive ability of pubertal male and female rats

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T. Zemunik

2003-07-01

Full Text Available Ten Fisher rats 50 to 55 days of age made up the pubertal group, and ten rats 90 to 95 days of age served as the controls. The testicular and epididymal weights and volumes of the pubertal males were lower than those of the controls (P0.05. At the beginning of gestation, the pubertal dams weighed less than the controls (P<0.001 but following uterectomy the body weights were equal. Pubertal dams delivered fewer pups than the controls (8.1 ± 2.5 vs 10.4 ± 1.3, P<0.05. There was no difference in the body weights of their offspring or in the weights of their placentas. The results suggest that, in contrast to their female counterparts, pubertal male rats are not fully mature and have not reached complete reproductive capacity at 50-55 days of age.

Pubertal development in Danish children

DEFF Research Database (Denmark)

Juul, A; Teilmann, G; Scheike, Thomas Harder

2006-01-01

differences between USA and Denmark, as well as to look for possible secular trends in pubertal development. Healthy Caucasian children from public schools in Denmark participated in the study which was carried out in 1991-1993. A total number of 826 boys and 1,100 girls (aged 6.0-19.9 years) were included......, and pubertal stages were assessed by clinical examination according to methods of Tanner. In boys testicular volume was determined using an orchidometer. We found that age at breast development 2 (B2) was 10.88 years, and mean menarcheal age was 13.42 years. Girls with body mass index (BMI) above the median...... genetic polymorphisms, nutrition, physical activity or endocrine disrupting chemicals must therefore also be considered. Therefore, we believe it is crucial to monitor the pubertal development closely in Denmark in the coming decades....

Effects of programmed physical activity on body composition in post-pubertal schoolchildren.

Science.gov (United States)

Farias, Edson Dos Santos; Gonçalves, Ezequiel Moreira; Morcillo, André Moreno; Guerra-Júnior, Gil; Amancio, Olga Maria Silverio

2015-01-01

To assess body composition modifications in post-pubertal schoolchildren after practice of a physical activity program during one school year. The sample consisted of 386 students aged between 15 and 17 years and divided into two groups: the study group (SG) comprised 195 students and the control group (CG), 191. The SG was submitted to a physical activity program and the CG attended conventional physical education classes. Body composition was assessed using body mass index (BMI), percentage of body fat (%BF), fat mass (FM), and lean mass (LM). A positive effect of the physical activity program on body composition in the SG (pgenders. A reduction in %BF (mean of differences = -5.58%) and waist circumference (-2.33 cm), as well as an increase in LM (+2.05 kg) were observed in the SG for both genders, whereas the opposite was observed in the CG. The practice of programmed physical activity promotes significant reduction of body fat in post-pubertal schoolchildren. Copyright © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

EFFECTS OF DIBUTYL PHTHALATE IN MALE RABBITS FOLLOWING IN UTERO, ADOLESCENT OR POST-PUBERTAL EXPOSURE

Science.gov (United States)

Effects of dibutyl phthalate in male rabbits following in utero, adolescent, or post-pubertal exposureTy T. Higuchi1, Jennifer S. Palmer1, L. Earl Gray Jr2., and D. N. Rao Veeramachaneni11Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort

Pubertal development in The Netherlands 1965-1997

NARCIS (Netherlands)

D. Mul (Dick); A.M. Fredriks; S. van Buuren (Stef); W. Oostdijk (Wilma); S.P. Verloove-Vanhorick; J.M. Wit (Jan)

2001-01-01

textabstractWe investigated pubertal development of 4019 boys and 3562 girls >8 y of age participating in a cross-sectional survey in The Netherlands and compared the results with those of two previous surveys. Reference curves for all pubertal stages were constructed. The 50th

Urinary phthalate excretion in 555 healthy Danish boys with and without pubertal gynaecomastia

DEFF Research Database (Denmark)

Mieritz, Mikkel G; Frederiksen, Hanne; Sørensen, Kaspar

2012-01-01

Pubertal gynaecomastia is a clinical sign of an oestrogen-androgen imbalance, which occurs in 40-60% of adolescent Caucasian boys. In most cases no underlying endocrinopathy can be identified. A recent study reports higher plasma phthalate levels in Turkish boys with pubertal gynaecomastia....... Therefore, we asked whether there was an association between concurrent measures of urinary phthalate metabolites and pubertal timing as well as the presence of gynaecomastia in otherwise healthy boys. We studied a total of 555 healthy boys (age 6.07-19.83 years) as part of the COPENHAGEN Puberty Study....... Anthropometry and pubertal stages (PH1-6 and G1-5) were evaluated, and the presence of gynaecomastia was assessed. Non-fasting blood samples were analysed for serum testosterone and morning urine samples were analysed for the total content of 12 phthalate metabolites (MEP, MnBP, MiBP, MBzP, MEHP, MEHHP, MEOHP...

Effects on steroid hormones secretion resulting from the acute stimulation of sectioning the superior ovarian nerve to pre-pubertal rats

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Morales-Ledesma Leticia

2012-10-01

Full Text Available Abstract In the adult rat, neural signals arriving to the ovary via the superior ovarian nerve (SON modulate progesterone (P4, testosterone (T and estradiol (E2 secretion. The aims of the present study were to analyze if the SON in the pre-pubertal rat also modulates ovarian hormone secretion and the release of follicle stimulating hormone (FSH and luteinizing (LH hormone. P4, T, E2, FSH and LH serum levels were measured 30 or 60 minutes after sectioning the SON of pre-pubertal female rats. Our results indicate that the effects on hormone levels resulting from unilaterally or bilaterally sectioning the SON depends on the analyzed hormone, and the time lapse between surgery and autopsy, and that the treatment yielded asymmetric results. The results also suggest that in the pre-pubertal rat the neural signals arriving to the ovaries via the SON regulate the enzymes participating in P4, T and E2 synthesis in a non-parallel way, indicating that the mechanisms regulating the synthesis of each hormone are not regulated by the same signals. Also, that the changes in the steroids hormones are not explained exclusively by the modifications in gonadotropins secretion. The observed differences in hormone levels between rats sacrificed 30 and 60 min after surgery reflect the onset of the compensatory systems regulating hormones secretion.

Two organizational effects of pubertal testosterone in male rats: transient social memory and a shift away from long-term potentiation following a tetanus in hippocampal CA1.

Science.gov (United States)

Hebbard, Pamela C; King, Rebecca R; Malsbury, Charles W; Harley, Carolyn W

2003-08-01

The organizational role of pubertal androgen receptor (AR) activation in synaptic plasticity in hippocampal CA1 and in social memory was assessed. Earlier data suggest pubertal testosterone reduces adult hippocampal synaptic plasticity. Four groups were created following gonadectomy at the onset of puberty: rats given testosterone; rats given testosterone but with the AR antagonist flutamide, present during puberty; rats given testosterone at the end of puberty; and rats given cholesterol at the end of puberty. A tetanus normally inducing long-term potentiation (LTP) was used to stimulate CA1 in the urethane-anesthetized adults during the dark phase of their cycle. Social memory was assessed prior to electrophysiology. Social memory for a juvenile rat at 120 min was seen only in rats not exposed to AR activation during puberty. Pubertal AR activation may induce the reduced social memory of male rats. Early CA1 LTP occurred following tetanus in rats with no pubertal testosterone. Short-term potentiation occurred in rats exposed to pubertal testosterone. Unexpectedly, rats with pubertal AR activation developed long-term depression (LTD). The same pattern was seen in normal male rats. Lack of LTP during the dark phase is consistent with other data on circadian modulation of CA1 LTP. No correlations were seen among social memory scores and CA1 plasticity measures. These data argue for two organizational effects of pubertal testosterone: (1) CA1 synaptic plasticity shifts away from potentiation toward depression; (2) social memory is reduced. Enduring effects of pubertal androgen on limbic circuits may contribute to reorganized behaviors in the postpubertal period.

Exciting fear in adolescence: Does pubertal development alter threat processing?

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Jeffrey M. Spielberg

2014-04-01

Full Text Available Adolescent development encompasses an ostensible paradox in threat processing. Risk taking increases dramatically after the onset of puberty, contributing to a 200% increase in mortality. Yet, pubertal maturation is associated with increased reactivity in threat-avoidance systems. In the first part of this paper we propose a heuristic model of adolescent affective development that may help to reconcile aspects of this paradox, which focuses on hypothesized pubertal increases in the capacity to experience (some fear-evoking experiences as an exciting thrill. In the second part of this paper, we test key features of this model by examining brain activation to threat cues in a longitudinal study that disentangled pubertal and age effects. Pubertal increases in testosterone predicted increased activation to threat cues, not only in regions associated with threat avoidance (i.e., amygdala, but also regions associated with reward pursuit (i.e., nucleus accumbens. These findings are consistent with our hypothesis that puberty is associated with a maturational shift toward more complex processing of threat cues—which may contribute to adolescent tendencies to explore and enjoy some types of risky experiences.

Exciting fear in adolescence: does pubertal development alter threat processing?

Science.gov (United States)

Spielberg, Jeffrey M; Olino, Thomas M; Forbes, Erika E; Dahl, Ronald E

2014-04-01

Adolescent development encompasses an ostensible paradox in threat processing. Risk taking increases dramatically after the onset of puberty, contributing to a 200% increase in mortality. Yet, pubertal maturation is associated with increased reactivity in threat-avoidance systems. In the first part of this paper we propose a heuristic model of adolescent affective development that may help to reconcile aspects of this paradox, which focuses on hypothesized pubertal increases in the capacity to experience (some) fear-evoking experiences as an exciting thrill. In the second part of this paper, we test key features of this model by examining brain activation to threat cues in a longitudinal study that disentangled pubertal and age effects. Pubertal increases in testosterone predicted increased activation to threat cues, not only in regions associated with threat avoidance (i.e., amygdala), but also regions associated with reward pursuit (i.e., nucleus accumbens). These findings are consistent with our hypothesis that puberty is associated with a maturational shift toward more complex processing of threat cues--which may contribute to adolescent tendencies to explore and enjoy some types of risky experiences. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Puberty and Pubertal Growth in GH-treated SGA Children: Effects of 2 Years of GnRHa Versus No GnRHa.

Science.gov (United States)

van der Steen, Manouk; Lem, Annemieke J; van der Kaay, Danielle C M; Hokken-Koèelega, Anita C S

2016-05-01

Most studies on puberty in children born small for gestational age (SGA) report height and age at onset of puberty. GH-treated SGA children with an adult height (AH) expectation below -2.5 SDS at onset of puberty can benefit from an additional 2 years of GnRH analog (GnRHa) treatment. There are no data on puberty and growth after discontinuation of GnRHa treatment in GH-treated SGA children. This study aimed to investigate the effects on puberty and pubertal growth of 2 years GnRHa vs no GnRHa in GH-treated SGA children. This was a GH trial involving 76 prepubertal short SGA children (36 girls) treated with GH. Thirty-two children received additional GnRHa for 2 years. Pubertal stages were 3-monthly assessed according to Tanner. Age, bone age, and median height at pubertal onset were lower in girls and boys in the GH/GnRHa group compared with the GH group. In girls and boys treated with GH/GnRHa, pubertal duration after stop of GnRHa treatment was shorter than pubertal duration in those with GH only (40.9 vs 46.7 mo; P = .044; 50.8 vs 57.5 months; P = .006; respectively). Height gain from onset of puberty until AH, including height gain during 2 years of GnRHa treatment, was 25.4 cm in girls and 33.0 cm in boys, which was 6.6 cm more than girls and boys treated with GH only. AH was similar in children treated with GH/GnRHa compared with those with GH only. GH-treated SGA children who start puberty with an AH expectation below -2.5 SDS and are treated with 2 years of GnRHa have a shorter pubertal duration after discontinuation of GnRHa compared with pubertal duration in children treated with GH only. Height gain from onset of puberty until AH is, however, more due to adequate growth during 2 years of GnRHa treatment resulting in a similar AH as children treated with GH only.

Granular Vulvovaginitis Syndrome in Nelore pubertal and post pubertal replacement heifers under tropical conditions: role of Mycoplasma spp., Ureaplasma diversum and BHV-1.

Science.gov (United States)

Gambarini, M L; Kunz, T L; Oliveira Filho, B D; Porto, R N G; Oliveira, C M G; Brito, W M E D; Viu, M A O

2009-10-01

In order to determine the role of Mycoplasma spp, Ureaplasma diversum and BHV-1 as causal agents of Granular Vulvovaginitis Syndrome in Nelore heifers raised under tropical conditions and based on the hypothesis that stressful conditions during puberty or breeding season would be a determinant factor for the infection, 340 heifers not vaccinated against BHV-1 were divided in Post-pubertal, in the beginning of the first breeding season, and Pubertal heifers. The vaginal lesion score (VLS) Grade 1 to 4 was giving according to lesion area and severity. Vaginal mucus was used to isolate Mycoplasma spp., Ureaplasma diversum and BHV-1. The predominant VLS was 2. No sample was positive for BHV-1; 48% were positive for Mycoplasma spp., Ureaplasma diversum, or both, with predominance of Ureaplasma diversum. Serum neutralization for BHV-1 showed more positive animals in pubertal group (23%); 3 of the paired sera demonstrated seroconversion. These data indicated that post-pubertal and pubertal Nelore heifers raised under extensive conditions are more susceptible to Mycoplasma spp. and Ureaplasma diversum. The hypothesis that the stress of pubertal period could lead to an acute vaginal infection by HBV-1 was not proofed.

Tamoxifen treatment for pubertal gynecomastia in two siblings with partial androgen insensitivity syndrome.

Science.gov (United States)

Saito, Reiko; Yamamoto, Yukiyo; Goto, Motohide; Araki, Shunsuke; Kubo, Kazuyasu; Kawagoe, Rinko; Kawada, Yasusada; Kusuhara, Koichi; Igarashi, Maki; Fukami, Maki

2014-01-01

Although tamoxifen has been shown to be fairly safe and effective for idiopathic pubertal gynecomastia, it remains unknown whether it is also beneficial for gynecomastia associated with endocrine disorders. Here, we report the effect of tamoxifen on pubertal gynecomastia in 2 siblings with partial androgen insensitivity syndrome (PAIS). Cases 1 and 2 presented with persistent pubertal gynecomastia at 13 and 16 years of age, respectively. Physical examinations revealed breast of Tanner stage 3 and normal male-type external genitalia in both cases. Clinical features such as female-type pubic hair and borderline small testis indicated mildly impaired masculinization. Molecular analysis identified a previously reported p.Arg789Ser mutation in the androgen receptor gene (AR) in the 2 cases. Two months of oral administration of tamoxifen ameliorated gynecomastia to Tanner stage 2 with no adverse events. Additional treatment with testosterone enanthate showed negligible effects on body hair and penile length. Hormone values of the 2 cases during tamoxifen treatment remained similar to those in previously reported untreated patients with PAIS. The results indicate that tamoxifen was effective in treating pubertal gynecomastia in these 2 patients with PAIS and may be considered as a therapeutic option in this situation pending further studies.

Putative effects of endocrine disrupters on pubertal development in the human

DEFF Research Database (Denmark)

Teilmann, Grete; Juul, Anders; Skakkebaek, Niels E

2002-01-01

developing countries to industrialized countries often develop precocious puberty. Not only precocious puberty, but also delayed puberty can, theoretically, be associated with exposure to endocrine disrupters. While it is very plausible that endocrine disrupters may disturb pubertal development...

Depressive symptoms among Hong Kong adolescents: relation to atypical sexual feelings and behaviors, gender dissatisfaction, pubertal timing, and family and peer relationships.

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Lam, T H; Stewart, Sunita M; Leung, Gabriel M; Lee, Peter W H; Wong, Joy P S; Ho, L M; Youth Sexuality Task Force

2004-10-01

A representative community sample of Hong Kong boys (n = 1,024) and girls (n = 1,403), age 14-18 years, provided information regarding same-sex attraction, gender dissatisfaction, pubertal timing, early experience with sexual intercourse, and depressive symptoms. They also rated the quality of their family and peer relationships and self-perceived attractiveness. Depressive symptoms were higher in youths reporting same-sex attraction, gender dissatisfaction, early pubertal maturation, and early sexual intercourse. Family relationships were less satisfactory for those who reported same-sex attraction, gender dissatisfaction, and early sexual intercourse, and peer relationships were also worse for those who reported gender dissatisfaction. In multivariate analyses, same-sex attraction, early sexual intercourse, and early pubertal maturation were unique and direct contributors to depressive symptoms; however, gender dissatisfaction's association with depressive symptoms was largely accounted for by shared correlations with negative family and peer relationships. The multivariate model explained 11% of the variance of depressive symptoms. These findings offer a preliminary documentation of the prevalence and correlates of atypical sexual self-assessments and behavior among adolescents in Hong Kong. Such information is important if theories of sexual identity and risk factors for depressive symptoms are to have cross-cultural utility. Copyright 2004 Springer Science + Business Media, Inc.

Longitudinal impacts of pubertal timing and weight status on adolescent Internet use: Analysis from a cohort study of Taiwanese youths.

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Meng-Che Tsai

Full Text Available To investigate the longitudinal impacts of pubertal timing and weight status on Internet use in adolescents.Three waves of data on a longitudinal cohort of 7th grade students (N = 2430 were retrieved from the Taiwan Youth Project. Univariate and multivariate regression models were applied using crude and adjusted odds ratios (OR with 95% confidence intervals (CI to examine the concomitant impacts of pubertal timing and weight status on adolescent Internet use.The dataset identified 210 (8.7% students using the Internet for more than 20 hours/week, and 81 (3.3% were viewing pornographic material online. Early maturing and thin-weight adolescents were at 35% and 46% increased risks of spending long hours on Internet use, respectively. While early puberty was associated with online pornography viewing among males (adjusted OR 1.84, 95% CI 1.04-3.28, early puberty was contrarily a protective factor against online gaming in females (adjusted OR 0.59, 95% CI 0.36-0.96.Early puberty was found to be positively related to adolescent Internet use. Appropriate health education and guidance regarding Internet use should be provided to those with different developing needs.

Longitudinal impacts of pubertal timing and weight status on adolescent Internet use: Analysis from a cohort study of Taiwanese youths.

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Tsai, Meng-Che; Strong, Carol; Chen, Wan-Ting; Lee, Chih-Ting; Lin, Chung-Ying

2018-01-01

To investigate the longitudinal impacts of pubertal timing and weight status on Internet use in adolescents. Three waves of data on a longitudinal cohort of 7th grade students (N = 2430) were retrieved from the Taiwan Youth Project. Univariate and multivariate regression models were applied using crude and adjusted odds ratios (OR) with 95% confidence intervals (CI) to examine the concomitant impacts of pubertal timing and weight status on adolescent Internet use. The dataset identified 210 (8.7%) students using the Internet for more than 20 hours/week, and 81 (3.3%) were viewing pornographic material online. Early maturing and thin-weight adolescents were at 35% and 46% increased risks of spending long hours on Internet use, respectively. While early puberty was associated with online pornography viewing among males (adjusted OR 1.84, 95% CI 1.04-3.28), early puberty was contrarily a protective factor against online gaming in females (adjusted OR 0.59, 95% CI 0.36-0.96). Early puberty was found to be positively related to adolescent Internet use. Appropriate health education and guidance regarding Internet use should be provided to those with different developing needs.

Electro convulsive therapy in a pre-pubertal child with severe depression.

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Russell P

2002-10-01

Full Text Available Electro Convulsive Therapy (ECT in pre-pubertal children is a controversial and underreported treatment. Even though the effectiveness and side effects of ECT in adolescents are comparable with those in adults, there is a pervasive reluctance to use ECT in children and adolescents. We report the case of a pre-pubertal child in an episode of severe depression with catatonic features, where a protracted course of ECT proved life-saving in spite of prolonged duration of seizures and delayed response to treatment. The case illustrates the safety and efficacy of ECT in children. Relevant literature is also reviewed along with the case report.

Pubertal status, interaction with significant others, and self-esteem of adolescent girls.

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Lacković-Grgin, K; Dekovíc, M; Opacić, G

1994-01-01

The aim of this study was to examine the relationship between pubertal status, the quality of interactions with significant others, and the self-esteem of adolescent girls. The model which was tested, hypothesized that pubertal status affects self-esteem through girls' interactions with their parents and friends. Pubertal status was operationalized as the number of months between occurrence of the first menstrual periods and time of the investigation. The measure of self-esteem was the shortened form of the Coopersmith Self-Esteem Inventory. Analyses revealed that girls who begun menstruating six months before the investigation obtained higher scores on the measure of self-esteem than did girls who had been menstruating 13 months or more. The best predictor of self-esteem, however, was the quality of interaction with their mothers. The results support the theoretical view that stresses the importance of interaction with significant others for the development of self-esteem.

Mobile phone radiation during pubertal development has no effect on testicular histology in rats.

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Tumkaya, Levent; Kalkan, Yildiray; Bas, Orhan; Yilmaz, Adnan

2016-02-01

Mobile phones are extensively used throughout the world. There is a growing concern about the possible public health hazards posed by electromagnetic radiation emitted from mobile phones. Potential health risk applies particularly to the most intensive mobile phone users-typically, young people. The aim of this study was to investigate the effects of mobile phone exposure to the testes, by assessing the histopathological and biochemical changes in the testicular germ cells of rats during pubertal development. A total of 12 male Sprague Dawley rats were used. The study group (n = 6) was exposed to a mobile phone for 1 h a day for 45 days, while the control group (n = 6) remained unexposed. The testes were processed with routine paraffin histology and sectioned. They were stained with hematoxylin-eosin, caspase 3, and Ki-67 and then photographed. No changes were observed between the groups (p > 0.05). The interstitial connective tissue and cells of the exposed group were of normal morphology. No abnormalities in the histological appearance of the seminiferous tubules, including the spermatogenic cycle stage, were observed. Our study demonstrated that mobile phones with a low specific absorption rate have no harmful effects on pubertal rat testicles. © The Author(s) 2013.

Pubertal testosterone influences threat-related amygdala-orbitofrontal cortex coupling.

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Spielberg, Jeffrey M; Forbes, Erika E; Ladouceur, Cecile D; Worthman, Carol M; Olino, Thomas M; Ryan, Neal D; Dahl, Ronald E

2015-03-01

Growing evidence indicates that normative pubertal maturation is associated with increased threat reactivity, and this developmental shift has been implicated in the increased rates of adolescent affective disorders. However, the neural mechanisms involved in this pubertal increase in threat reactivity remain unknown. Research in adults indicates that testosterone transiently decreases amygdala-orbitofrontal cortex (OFC) coupling. Consequently, we hypothesized that increased pubertal testosterone disrupts amygdala-OFC coupling, which may contribute to developmental increases in threat reactivity in some adolescents. Hypotheses were tested in a longitudinal study by examining the impact of testosterone on functional connectivity. Findings were consistent with hypotheses and advance our understanding of normative pubertal changes in neural systems instantiating affect/motivation. Finally, potential novel insights into the neurodevelopmental pathways that may contribute to adolescent vulnerability to behavioral and emotional problems are discussed. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Maths performance as a function of sex, laterality, and age of pubertal onset.

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Sappington, John; Topolski, Richard

2005-07-01

Sex differences in math/spatial performance demand explanations. Within the biological view, the complexity and number of variables make the explanation difficult at best. Laterality and age of pubertal onset have been investigated prominently in this context but rarely considered as interactions in the same study. Some 468 college subjects with SAT MATH (SAT M) scores were divided into 12 groups defined by sex, laterality, and age (early, middle, and late) of pubertal onset. Significant main effects for sex and age of onset emerged, as did an interaction between lateral preference and pubertal onset. Generally males outperformed females. The combination of maleness, sinistrality, and early maturation was associated with high SAT M scores. Sinistrality and late maturation among females predicted very poor math performance.

Adolescents' Increasing Stress Response to Social Evaluation: Pubertal Effects on Cortisol and Alpha-Amylase during Public Speaking

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van den Bos, Esther; de Rooij, Mark; Miers, Anne C.; Bokhorst, Caroline L.; Westenberg, P. Michiel

2014-01-01

Stress responses to social evaluation are thought to increase during adolescence, which may be due to pubertal maturation. However, empirical evidence is scarce. This study is the first to investigate the relation between pubertal development and biological responses to a social-evaluative stressor longitudinally. Participants performed the Leiden…

The mammary gland is a sensitive pubertal target in CD-1 and C57Bl/6 mice following perinatal perfluorooctanoic acid (PFOA) exposure.

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Tucker, Deirdre K; Macon, Madisa B; Strynar, Mark J; Dagnino, Sonia; Andersen, Erik; Fenton, Suzanne E

2015-07-01

Perfluorooctanoic acid (PFOA) is a developmental toxicant in mice, with varied strain outcomes depending on dose and period of exposure. The impact of PFOA on female mouse pubertal development at low doses (≤1mg/kg) has yet to be determined. Therefore, female offspring from CD-1 and C57Bl/6 dams exposed to PFOA, creating serum concentrations similar to humans, were examined for pubertal onset, including mammary gland development. Pups demonstrated a shorter PFOA elimination half-life than that reported for adult mice. Prenatal exposure to PFOA caused significant mammary developmental delays in female offspring in both strains. Delays started during puberty and persisted into young adulthood; severity was dose-dependent. Also an evaluation of female serum hormone levels and pubertal timing onset revealed no effects of PFOA compared to controls in either strain. These data suggest that the mammary gland is more sensitive to early low level PFOA exposures compared to other pubertal endpoints, regardless of strain. Published by Elsevier Inc.

Fertility of the Small East African goat following pre-pubertal infection with Trypanosoma congolense

International Nuclear Information System (INIS)

O'Hara, H.B.; Gombe, S.

1991-01-01

Pre-pubertal male and female Small East African goats were infected with Trypanosoma congolense at 4-5 months of age. Changes in body weight and haemogram were monitored weekly. Progesterone and testosterone measurements were made three times weekly until the goats either reached puberty or 18 months of age. Onset of puberty was determined from observation of oestrus behaviour, mating or increase in libidio; this was confirmed by elevation in plasma progesterone or testosterone levels. Trypanosomiasis affected pre-pubertal goats by reducing body weight gain and delaying onset of puberty. Histological examination of the gonads showed pronounced pathological changes. These effects were reversed by treatment with isometamidium chloride (Samorin, May and Baker). It was concluded that early treatment of infected goats before serious gonadal damage could occur allowed full restoration of reproductive function. (author). 6 refs, 4 figs, 1 tab

Pubertal stage and the prevalence of violence and social relational aggression

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Hemphill, Sheryl A.; Kotevski, Aneta; Herrenkohl, Todd I.; Toumbourou, John W.; Carlin, John B.; Catalano, Richard F.; Patton, George C.

2010-01-01

Objective Violence and social relational aggression are global problems that become prominent in early adolescence. This study examines associations between pubertal stage and adolescent violent behavior and social relational aggression. Methods This paper draws on cross-sectional data from the International Youth Development Study (IYDS), which comprised two state-wide representative samples of students in grades 5, 7 and 9 (N = 5,769) in Washington State in the United States and Victoria, Australia, drawn as a 2-stage cluster sample in each state. The study used carefully matched methods to conduct a school-administered, self-report student survey measuring behavioral outcomes including past year violent behavior (measured as attacking or beating up another person) and social relational aggression (excluding peers from the group, threatening to spread lies or rumors), as well as a comprehensive range of risk and protective factors and pubertal development. Results Compared with early puberty, the odds of violent behavior were approximately three-fold higher in mid-puberty (odds ratio [OR]: 2.87; 95% confidence interval [CI]: 1.81,4.55) and late puberty (OR: 3.79; 95% CI: 2.25,6.39), after adjustment for age, gender, state, and state by gender interaction. For social relational aggression, there were weaker overall associations after adjustment but these included an interaction between pubertal stage and age, showing stronger associations with pubertal stage at younger age (p = .003; mid-puberty OR 1.78; 95% CI 1.20,2.63; late puberty OR 3.00; 95% CI 1.95,4.63. Associations between pubertal stage and violent behavior and social relational aggression remained (although the magnitude of effects was reduced), after the inclusion of social contextual mediators in the analyses. Conclusions Pubertal stage was associated with higher rates of violent behavior and social relational aggression, with the latter association seen only at younger ages. Puberty may be an

Duration of the pubertal peak in skeletal Class I and Class III subjects.

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Kuc-Michalska, Małgorzata; Baccetti, Tiziano

2010-01-01

To estimate and compare the duration of the pubertal growth peak in Class I and Class III subjects. The data examined consisted of pretreatment lateral cephalometric records of 218 skeletal Class I or Class III subjects (93 female and 125 male subjects) of white ancestry. The duration of the pubertal peak was calculated from the average chronological age intervals between stages CS3 and CS4 of the cervical vertebral maturation in Class I vs Class III groups (t-test). In skeletal Class I subjects, the pubertal peak had a mean duration of 11 months, whereas in Class III subjects it lasted 16 months. The average difference (5 months) was statistically significant (P < .001). The growth interval corresponding to the pubertal growth spurt (CS3-CS4) was longer in Class III subjects than in subjects with normal skeletal relationships; the larger increases in mandibular length during the pubertal peak reported in the literature for Class III subjects may be related to the longer duration of the pubertal peak.

Gender specific effect of major dietary patterns on the metabolic syndrome risk in Korean pre-pubertal children

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Park, Soo Jin; Lee, Seung Min; Kim, Seon Mee; Lee, Myoungsook

2013-01-01

There is a lack of data on metabolic risk factors during pre-puberty, which is important for identifying the subgroups of youth, at whom early interventions should be targeted. In this study, we evaluated the prevalence of metabolic risk factors and its subsequent relations with dietary patterns in Korean pre-pubertal children through a cross-sectional sample (n = 1,008; boys = 513) of pre-pubertal children (aged 8-9 years) from a sub-study of the Korea Metabolic Syndrome Research Initiatives...

Brain Maturation, Cognition and Voice Pattern in a Gender Dysphoria Case under Pubertal Suppression.

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Schneider, Maiko A; Spritzer, Poli M; Soll, Bianca Machado Borba; Fontanari, Anna M V; Carneiro, Marina; Tovar-Moll, Fernanda; Costa, Angelo B; da Silva, Dhiordan C; Schwarz, Karine; Anes, Maurício; Tramontina, Silza; Lobato, Maria I R

2017-01-01

Introduction: Gender dysphoria (GD) (DMS-5) is a condition marked by increasing psychological suffering that accompanies the incongruence between one's experienced or expressed gender and one's assigned gender. Manifestation of GD can be seen early on during childhood and adolescence. During this period, the development of undesirable sexual characteristics marks an acute suffering of being opposite to the sex of birth. Pubertal suppression with gonadotropin releasing hormone analogs (GnRHa) has been proposed for these individuals as a reversible treatment for postponing the pubertal development and attenuating psychological suffering. Recently, increased interest has been observed on the impact of this treatment on brain maturation, cognition and psychological performance. Objectives: The aim of this clinical report is to review the effects of puberty suppression on the brain white matter (WM) during adolescence. WM Fractional anisotropy, voice and cognitive functions were assessed before and during the treatment. MRI scans were acquired before, and after 22 and 28 months of hormonal suppression. Methods: We performed a longitudinal evaluation of a pubertal transgender girl undergoing hormonal treatment with GnRH analog. Three longitudinal magnetic resonance imaging (MRI) scans were performed for diffusion tensor imaging (DTI), regarding Fractional Anisotropy (FA) for regions of interest analysis. In parallel, voice samples for acoustic analysis as well as executive functioning with the Wechsler Intelligence Scale (WISC-IV) were performed. Results: During the follow-up, white matter fractional anisotropy did not increase, compared to normal male puberty effects on the brain. After 22 months of pubertal suppression, operational memory dropped 9 points and remained stable after 28 months of follow-up. The fundamental frequency of voice varied during the first year; however, it remained in the female range. Conclusion: Brain white matter fractional anisotropy

The physiology and timing of male puberty

DEFF Research Database (Denmark)

Tinggaard, Jeanette; Mieritz, Mikkel Grunnet; Sørensen, Kaspar

2012-01-01

To describe available markers of male puberty, discuss associations between adiposity and pubertal timing and to review recent evidence of a possible secular trend in male pubertal timing.......To describe available markers of male puberty, discuss associations between adiposity and pubertal timing and to review recent evidence of a possible secular trend in male pubertal timing....

The Effect of Wallow on Growth Performance of Pre-Pubertal Pigs in ...

African Journals Online (AJOL)

A study was carried out to determine the influence of wallow on the growth performance of growing pigs. Sixteen (16) pre-pubertal pigs (8 males and 8 females) of large white breed, aged three months were randomly assigned to two treatments. There were eight animals per group designated as treatment A = with wallow ...

Pubertal development among girls with classical congenital adrenal hyperplasia initiated on treatment at different ages

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Bindu Kulshreshtha

2012-01-01

Full Text Available Introduction: Children with congenital adrenal hyperplasia (CAH provide us an opportunity to study the clinical effects of androgen excess in humans. We studied the sequence of pubertal development in girls with congenital adrenal hyperplasia initiated on treatment at different ages, to assess the effects of androgen exposure on the Hypothalamic-Pituitary-Ovarian (HPO axis. Materials and Methods: Girls more than 18 years of age, with CAH, on follow-up at this hospital were the subjects for this study. Details of history, physical findings, laboratory evaluation, and medication were noted from their case records and verified from the patients and their / parents, in addition to assessment of their present health status. Result: We studied 24 patients of classical CAH (SW-2, SV-22, average age - 24.5 ± 6.6 years. All had varying degrees of genital ambiguity (Prader stage 3 (n = 13, Prader stage 2 (n = 10, Prader stage 1 (n = 1. Among them were13 girls, who were started on steroids after eight years of age. Girls who received treatment from infancy and early childhood had normal pubertal development (mean age at menarche 11.4 ± 1.7 years. Hirsutism was not a problem among them. Untreated children had progressive clitoral enlargement throughout childhood, developed pubic hair at around three to six years of age, and facial hair between nine and eleven years. Plasma testosterone ranged from 3 to 6 ng / ml prior to treatment. Six of the 13 untreated CAH girls had subtle breast development starting at ages 11 - 16 years and three had spontaneous infrequent vaginal bleeding starting at ages 11 - 17. Steroid supplementation initiated pubertal changes in older girls in two-to-six months′ time. Conclusion: There was a delay in HPO axis maturation (as evidenced by delayed pubertal development in the absence of treatment in girls with CAH. This could be corrected with steroid supplementation.

Pubertal stage and the prevalence of violence and social/relational aggression.

Science.gov (United States)

Hemphill, Sheryl A; Kotevski, Aneta; Herrenkohl, Todd I; Toumbourou, John W; Carlin, John B; Catalano, Richard F; Patton, George C

2010-08-01

We examined associations between pubertal stage and violent adolescent behavior and social/relational aggression. The International Youth Development Study comprises statewide representative student samples in grades 5, 7, and 9 (N = 5769) in Washington State and Victoria, Australia, drawn as a 2-stage cluster sample in each state. We used a school-administered, self-report student survey to measure previous-year violent behavior (ie, attacking or beating up another person) and social/relational aggression (excluding peers from the group, threatening to spread lies or rumors), as well as risk and protective factors and pubertal development. Cross-sectional data were analyzed. Compared with early puberty, the odds of violent behavior were approximately threefold higher in midpuberty (odds ratio [OR]: 2.87 [95% confidence interval (CI): 1.81-4.55]) and late puberty (OR: 3.79 [95% CI: 2.25-6.39]) after adjustment for demographic factors. For social/relational aggression, there were weaker overall associations after adjustment, but these associations included an interaction between pubertal stage and age, and stronger associations with pubertal stage at younger age were shown (P = .003; midpuberty OR: 1.78 [95% CI: 1.20-2.63]; late puberty OR: 3.00 [95% CI: 1.95-4.63]). Associations between pubertal stage and violent behavior and social/relational aggression remained after the inclusion of social contextual mediators in the analyses. Pubertal stage was associated with higher rates of violent behavior and social/relational aggression, with the latter association seen only at younger ages. Puberty is an important phase at which to implement prevention programs to reduce adolescent violent and antisocial behaviors.

EFFECT OF GnRH AND PHOSPHORUS IN DELAYED PUBERTAL SURTI BUFFALO HEIFERS

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H.B. Dhamsaniya

2016-06-01

Full Text Available The study was conducted on eighteen delayed pubertal Surti buffalo heifers, divided into three equal groups (6 in each to evaluate the efficacy of GnRH alone and in combination of phosphorus. The buffalo heifers in Group-I and Group-II were treated with Buserelin acetate (5 ml, IM. Buffalo heifers in Group-II also received additional injection of Toldimphos sodium (10 ml, IM at 3 day interval for 4 times, while buffalo heifers in Group-III served as control. The percentage of induced estrus was highest (83.33% in each treated groups as compared to control group (50%. The mean estrus induction intervals were significantly (P<0.05 shorter in Group-I (20.20 ± 2.18 days and Group-II (18.80 ± 2.32 days as compared to control group (30.24 ± 0.81 days. The conception rate at induced estrus was highest in Group-II (50% followed by Group-I (33.33%. The plasma progesterone levels being significantly lowest on the day of estrus (less than 0.5 ng/ml as compared to pre-treatment days in all groups. The mean total protein and triglycerides levels were differed significantly between the groups on the day of estrus and being significantly higher in Group-II as compared to Group-I and III on that day. A significantly higher level of cholesterol in both treatment groups as compared to the control group during different intervals and also being higher on the day of estrus as compared to pre-treatment days. The mean plasma glucose levels were differed nonsignificantly between and within the treatment and control groups. It is concluded that estrus can be successfully induced in delayed pubertal heifers with the use of GnRH alone and in combination with phosphorus.

Repeatability and accuracy of reproductive tract scoring to determine pubertal status in beef heifers.

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Rosenkrans, Kelly S; Hardin, David K

2003-03-01

The objective of this study was to compare the repeatability and accuracy of palpation per rectum to transrectal ultrasonography and serum progesterone concentrations for determining pubertal status in beef heifers. One hundred and seventy-four rectal examinations were performed on 29 predominantly Angus heifers by two veterinarians (A and B) and assigned individual reproductive tract scores (RTS) during monthly examinations over a 3-month period. Heifers were examined in the morning by both veterinarians, randomized, and re-examined in the afternoon. The size and location of ovarian structures of each heifer were determined by ultrasonography. Heifers with follicles >10mm in diameter or corpora lutea were classified as pubertal. Serum progesterone concentrations at the time of the examination and 10 days later were determined by radioimmunoassay and used to classify heifers as prepubertal (or=1 ng/ml). Kappa, which describes degree of agreement beyond chance, was used to determine repeatability of the RTS system. Multicategory Kappa for agreement was 0.64 within veterinarian, 0.46 between veterinarian, and 0.35 between palpation per rectum and transrectal ultrasonography. Sensitivity and specificity of palpation per rectum for diagnosis of pubertal status compared to serum progesterone levels were higher (82 and 69%, respectively) than sensitivity and specificity of ultrasonography (79 and 59%, respectively). This study validates the RTS system as a repeatable and accurate screening test to evaluate pubertal status in groups of heifers prior to the onset of the breeding season.

Putative effects of endocrine disrupters on pubertal development in the human

DEFF Research Database (Denmark)

Teilmann, Grete; Juul, Anders; Skakkebaek, Niels E

2002-01-01

-called endocrine disrupters. Precocious puberty has been described in several case reports of accidental exposure to oestrogenic compounds in cosmetic products, food and pharmaceuticals. Local epidemics of premature thelarche have also been suggested to be linked to endocrine disrupters. Children adopted from...... developing countries to industrialized countries often develop precocious puberty. Not only precocious puberty, but also delayed puberty can, theoretically, be associated with exposure to endocrine disrupters. While it is very plausible that endocrine disrupters may disturb pubertal development...

Gingival crevicular fluid alkaline phosphatase activity in relation to pubertal growth spurt and dental maturation: A multiple regression study

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Perinetti, G.

2016-04-01

Full Text Available Introduction: The identification of the onset of the pubertal growth spurt has major clinical implications when dealing with orthodontic treatment in growing subjects. Aim: Through multivariate methods, this study evaluated possible relationships between the gingival crevicular fluid (GCF alkaline phosphatase (ALP activity and pubertal growth spurt and dentition phase. Materials and methods: One hundred healthy growing subjects (62 females, 38 males; mean age, 11.5±2.4 years were enrolled into this doubleblind, prospective, cross-sectional-design study. Phases of skeletal maturation (pre - pubertal, pubertal, post - pubertal was assessed using the cervical vertebral maturation method. Samples of GCF for the ALP activity determination were collected at the mesial and distal sites of the mandibular central incisors. The phases of the dentition were recorded as intermediate mixed, late mixed, or permanent. A multinomial multiple logistic regression model was used to assess relationships of the enzymatic activity to growth phases and dentition phases. Results: The GCF ALP activity was greater in the pubertal growth phase as compared to the pre - pubertal and post - pubertal growth phases. Significant adjusted odds ratios for the GCF ALP activity for the pre - pubertal and post - pubertal subjects, in relation to the pubertal group, were 0.76 and 0.84, respectively. No significant correlations were seen for the dentition phase. Conclusions: The GCF ALP activity is a valid candidate as a non - invasive biomarker for the identification of the pubertal growth spurt irrespective of the dentition phase.

Exciting fear in adolescence: Does pubertal development alter threat processing?

OpenAIRE

Spielberg, JM; Olino, TM; Forbes, EE; Dahl, RE

2014-01-01

Adolescent development encompasses an ostensible paradox in threat processing. Risk taking increases dramatically after the onset of puberty, contributing to a 200% increase in mortality. Yet, pubertal maturation is associated with increased reactivity in threat-avoidance systems. In the first part of this paper we propose a heuristic model of adolescent affective development that may help to reconcile aspects of this paradox, which focuses on hypothesized pubertal increases in the capacity t...

The organizational effects of pubertal testosterone on sexual proficiency in adult male Syrian hamsters.

Science.gov (United States)

De Lorme, Kayla C; Sisk, Cheryl L

2016-10-15

Social proficiency requires making appropriate behavioral adaptations as a result of social experience. For example, male rodents become sexually proficient with experience as demonstrated by a reduction in ectopic (misdirected) mounts, mount-to-intromission ratio, and latency to ejaculation. We previously found that over a series of timed tests with a receptive female, male hamsters deprived of testosterone specifically during puberty (NoT@P) have overall lower levels of sexual behavior and continue to display high levels of ectopic mounts, compared with males that experienced endogenous testosterone during puberty (T@P). These results suggested that pubertal testosterone programs sexual proficiency in adulthood, but because NoT@P males engaged in less sexual behavior than T@P males in these tests, the amount of sexual experience may have been insufficient to improve sexual proficiency. To more rigorously test the hypothesis that pubertal testosterone is necessary for social proficiency in adulthood, the present study compared the behavior of NoT@P and T@P males in a series of 4 trials with a 48-h interval between each trial. Sexual experience was equated by limiting each trial to 5 intromissions. Sexually-naïve males were either gonadectomized prepubertally (NoT@P) or in adulthood (T@P) and received subcutaneous testosterone capsules four weeks later. Two weeks after testosterone replacement, these groups and a group of adult gonad-intact controls began sexual behavior testing. We found that NoT@P males had more ectopic mounts/min across all four tests compared to gonad-intact and T@P males. Moreover, both gonad-intact and T@P males, but not NoT@P males, showed an increase in the number of mounts and intromissions/min between trials 1 and 3. Unexpectedly, both gonad-intact and T@P, but not NoT@P, males showed a decrease in sexual behaviors during trial 4. Thus, T@P males display multiple behavioral adaptations to sexual experience that are not observed in No

Early pubertal onset and its relationship with sexual risk taking, substance use and anti-social behaviour: a preliminary cross-sectional study

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Bellis Mark A

2009-12-01

Full Text Available Abstract Background In many countries age at pubertal onset has declined substantially. Relatively little attention has been paid to how this decline may affect adolescent behaviours such as substance use, violence and unprotected sex and consequently impact on public health. Methods In the UK, two opportunistic samples (aged 16-45 years, paper-based (n = 976 and online (n = 1117, examined factors associated with earlier pubertal onset and whether earlier age of onset predicted sexual risk-taking, substance use and anti-social behaviours during early adolescence. Results Overall, 45.6% of females reported menarche ≤ 12 years and 53.3% of males were categorised as having pubertal onset ≤ 11 years. For both sexes earlier pubertal onset was associated with poorer parental socio-economic status. Other pre-pubertal predictors of early onset were being overweight, more childhood illnesses (females and younger age at time of survey (males. For both sexes earlier puberty predicted having drunk alcohol, been drunk, smoked and used drugs Conclusion Results provide sufficient evidence for changes in age of pubertal onset to be further explored as a potential influence on trends in adolescent risk behaviours. Further insight into the relationship between early puberty and both obesity and socio-economic status may help inform early interventions to tackle the development of risk behaviours and health inequalities during early adolescence.

Sex Variations in Youth Anxiety Symptoms: Effects of Pubertal Development and Gender Role Orientation

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Carter, Rona; Silverman, Wendy K.; Jaccard, James

2011-01-01

This study evaluated whether pubertal development and gender role orientation (i.e., masculinity and femininity) can partially explain sex variations in youth anxiety symptoms among clinic-referred anxious youth (N = 175; ages 9-13 years; 74% Hispanic; 48% female). Using youth and parent ratings of youth anxiety symptoms, structural equation…

The Few, the Changing, the Different: Pubertal Onset, Perceived School Climate and Body Image in Ethnically Diverse Sixth Grade Girls

OpenAIRE

Morales, Jessica

2012-01-01

The present study examined the impact of pubertal onset, race/ethnicity, and school racial/ethnic composition on girls' body image and perceived school climate (school safety, school liking, and loneliness in school) during the middle school transition. The sample (N = 1,626) included 6th grade Black, Mexican American, White, and Asian girls from 20 diverse middle schools. Hierarchical analyses supported both the early-timing and stressful change hypothesis. That is, experiencing pubertal ons...

Prenatal and pubertal testosterone affect brain lateralization

NARCIS (Netherlands)

Beking, T; Geuze, R H; van Faassen, M; Kema, I P; Kreukels, B P C; Groothuis, T G G

After decades of research, the influence of prenatal testosterone on brain lateralization is still elusive, whereas the influence of pubertal testosterone on functional brain lateralization has not been investigated, although there is increasing evidence that testosterone affects the brain in

Peri-pubertal gonadotropin-releasing hormone agonist treatment affects sex biased gene expression of amygdala in sheep.

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Nuruddin, Syed; Krogenæs, Anette; Brynildsrud, Ola Brønstad; Verhaegen, Steven; Evans, Neil P; Robinson, Jane E; Haraldsen, Ira Ronit Hebold; Ropstad, Erik

2013-12-01

The nature of hormonal involvement in pubertal brain development has attracted wide interest. Structural changes within the brain that occur during pubertal development appear mainly in regions closely linked with emotion, motivation and cognitive functions. Using a sheep model, we have previously shown that peri-pubertal pharmacological blockade of gonadotropin releasing hormone (GnRH) receptors, results in exaggerated sex-differences in cognitive executive function and emotional control, as well as sex and hemisphere specific patterns of expression of hippocampal genes associated with synaptic plasticity and endocrine signaling. In this study, we explored effects of this treatment regime on the gene expression profile of the ovine amygdala. The study was conducted with 30 same-sex twin lambs (14 female and 16 male), half of which were treated with the GnRH agonist (GnRHa) goserelin acetate every 4th week, beginning before puberty, until approximately 50 weeks of age. Gene expression profiles of the left and right amygdala were measured using 8×15 K Agilent ovine microarrays. Differential expression of selected genes was confirmed by qRT-PCR (Quantitative real time PCR). Networking analyses and Gene Ontology (GO) Term analyses were performed with Ingenuity Pathway Analysis (IPA), version 7.5 and DAVID (Database for Annotation, Visualization and integrated Discovery) version 6.7 software packages, respectively. GnRHa treatment was associated with significant sex- and hemisphere-specific differential patterns of gene expression. GnRHa treatment was associated with differential expression of 432 (|logFC|>0.3, adj. p value expressed as a result of GnRHa treatment in the male animals. The results indicated that GnRH may, directly and/or indirectly, be involved in the regulation of sex- and hemisphere-specific differential expression of genes in the amygdala. This finding should be considered when long-term peri-pubertal GnRHa treatment is used in children. Copyright �

Induction of a hypothyroid state during juvenile development delays pubertal reactivation of the neuroendocrine system governing luteinising hormone secretion in the male rhesus monkey (Macaca mulatta).

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Mann, D R; Bhat, G K; Stah, C D; Pohl, C R; Plant, T M

2006-09-01

The present study aimed to determine the influence of thyroid status on the timing of the pubertal resurgence in gonadotrophin-releasing hormone pulse generator activity [tracked by circulating luteinising hormone (LH) levels] in male rhesus monkeys. Six juvenile monkeys were orchidectomised and then treated with the antithyroid drug, methimazole, from 15-19 months until 36 months of age, at which time thyroxine (T(4)) replacement was initiated. Four additional agonadal monkeys served as controls. Blood samples were drawn weekly for hormonal assessments. Body weight, crown-rump length and bone age were monitored at regular intervals. By 8 weeks of methimazole treatment, plasma T(4) had fallen sharply, and the decline was associated with a plasma thyroid-stimulating hormone increase. In controls, plasma LH levels remained undetectable until the pubertal rise occurred at 29.3 +/- 0.2 months of age. This developmental event occurred in only half of the methimazole-treated animals before 36 months of age when T(4) replacement was initiated. The hypothyroid state was associated with a profound arrest of growth and bone maturation, but increased body mass indices and plasma leptin levels. T(4) replacement in methimazole-treated monkeys was associated with the pubertal rise in LH in the remaining three animals and accelerated somatic development in all six animals. Although pubertal resurgence in LH secretion occurred at a later chronological age in methimazole-treated animals compared to controls, bone age, crown-rump length and body weight at that time did not differ between groups. There were no long-term differences in plasma prolactin between groups. We conclude that juvenile hypothyroidism in male primates causes a marked delay in the pubertal resurgence of LH secretion, probably occasioned at the hypothalamic level. Whether this effect is meditated by an action of thyroid hormone directly on the hypothalamus or indirectly as a result of the concomitant deficit in

Serum AMH levels are lower in healthy boys who develop pubertal gynaecomastia

DEFF Research Database (Denmark)

Mieritz, Mikkel G.; Hagen, Casper P.; Almstrup, Kristian

2015-01-01

Background: Pubertal gynaecomastia is thought to be a clinical sign of an oestrogen-androgen imbalance, affecting up to 60% of boys. In most cases no underlying endocrinopathy can be identified. In boys, Anti-mullerian hormone (AMH) is produced by immature Sertoli cells and circulating level...... decreases as testosterone increases during pubertal maturation. In a previous cross sectional study we found significant lower levels of AMH in boys with pubertal gynaecomastia (Mieritz et al., Clin Endocrinol, 2013). Objective and hypotheses: To investigate serum AMH levels and genetic polymorphisms...... in boys with or without gynaecomastia. Method: 99 healthy Danish boys (aged 5.8-16.4 years) were followed in a prospective cohort over 8 years with semi-annual examinations (total examinations, n=951), including breast palpations and blood samples. Serum AMH concentrations were analysed by immunoassay...

Deleterious effects of obesity on physical fitness in pre-pubertal children.

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Ceschia, Arianna; Giacomini, Stefano; Santarossa, Simone; Rugo, Miriam; Salvadego, Desy; Da Ponte, Alessandro; Driussi, Caterina; Mihaleje, Martina; Poser, Stefano; Lazzer, Stefano

2016-01-01

The prevalence of obesity in children has increased dramatically during the past decades in Europe and understanding physical fitness and its components in children is critical to design and implement effective interventions. The objective of the present study was to analyse the association between physical fitness (aerobic, speed, agility, power, flexibility and balance) and body mass index (BMI) in pre-pubertal children. A total of 2411 healthy schoolchildren (7-11 years) participated in this study. Anthropometric characteristics and body composition were assessed by skinfold thickness. Physical fitness was measured by nine physical fitness tests: endurance running, 20 m running speed, agility, handgrip strength, standing long jump and squat jump, sit and reach, medicine ball forward throw and static balance. No relevant differences were observed between boys and girls regarding anthropometric characteristics, body composition and physical fitness. However, overweight and obese children showed significantly lower physical fitness levels in endurance running, speed and agility (mean: +18.8, +5.5 and +14.5% of time to complete tasks, respectively), lower limb power normalised to body mass (-23.3%) and balance tests (number of falls: +165.5%) than their normal weight counterparts. On the other hand, obesity did not affect handgrip, throwing and flexibility. In conclusion, increased BMI was associated with lower performance capabilities limiting proper motor skill development, which directly affects the ability of children to take on sports skills. Actions undertaken to promote children's wellness and fitness should be prioritised and introduced early in life with the aim of enhancing physical fitness as well as preventing overweight and obesity.

Investigation of pre-pubertal sex differences in wheel running and social behavior in three mouse strains.

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Gordon, Elizabeth A; Corbitt, Cynthia

2015-08-01

Sex differences in social behaviors exist in mammals during adulthood, and further evidence suggests that sex differences in behavior are present before sexual maturity. In order to model behavioral disorders in animals, it is important to assess baseline sex-related behavioral differences, especially when studying disorders for which sex-related behavioral effects are expected. We investigated the effect of sex on behavior in 3 strains of pre-pubertal mice (C57BL/6, CFW, and CF1) using a wheel-running assay. We found no significant sex differences in latency to run on the wheel or total duration of wheel running within each strain. During the social interaction test, there were no differences between sexes in latency or total duration of contact or following between a subject and novel mouse. We also evaluated behavioral patterns of wheel running and stereotypical behaviors, such as burrowing and grooming. Both sexes showed characteristic wheel running behavior, spending the majority of each trial interacting with the wheel when it was free and more time performing other activities ( e.g. , stereotypical behaviors, general locomotion) when it was jammed. These results provide evidence that, among various strains of pre-pubertal mice, baseline sex-related behavioral differences are not strong enough to influence the measured behaviors.

Course and forecast of the hypothalamic pubertal syndrome

International Nuclear Information System (INIS)

Kayusheva, I.V.

1987-01-01

A total of 223 patients with the hypothalamic pubertal syndrome (HPS) were followed up for 1 to 22 years. The course of HPS was regressive, stable , recurrent or progressive and dependent on the initial depth and spread of hypothalamic lesion, repeated unfavourable hypothalamic exposures, and timely and regular treatment. HPS outcomes were followed up in 190 cases. The recovery was complete in 21.05%, obesity alone persisted in 10.53%, vegetovascular dystonia was persistent in 7.36%, and polycystic ovaries in 5.79%. Neuroendocrine hypothalamic syndrome was the most common (50.53%) HPS outcome. Hormone levels in blood were investigated using radioimmunoassay in patients with neuroendocrine form of HPS

THE EFFECT OF ATRAZINE ON PUBERTY IN THE MALE WISTAR RATS: AN EVALUATION IN THE PROTOCOL FOR THE ASSESSMENT OF PUBERTAL DEVELOPMENT AND THYROID FUNCTION

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Since atrazine (ATR), a chlorotriazine herbicide, has been shown previously to alter the secretion of luteinizing hormone (LH) and prolactin (PRL) through a direct effect on the central nervous system (CNS), we hypothesized that exposure to ATR in the EDSTAC male pubertal protoco...

Cumulative and antagonistic effects of a mixture of the antiandrogens vinclozolin and iprodione in the pubertal male rat.

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Blystone, Chad R; Lambright, Christy S; Cardon, Mary C; Furr, Johnathan; Rider, Cynthia V; Hartig, Phillip C; Wilson, Vickie S; Gray, Leon E

2009-09-01

Vinclozolin and iprodione are dicarboximide fungicides that display antiandrogenic effects in the male rat, which suggests that a mixture would lead to cumulative effects on androgen-sensitive end points. Iprodione is a steroid synthesis inhibitor, but androgen receptor antagonist activity, which is displayed by vinclozolin, has not been fully evaluated. Here, we demonstrate that iprodione binds to the human androgen receptor (IC(50) = 86.0 microM), reduces androgen-dependent gene expression, and reduces androgen-sensitive tissue weights in castrated male rats (Hershberger assay). Since vinclozolin and iprodione affect common targets in the pubertal male rat, we tested the hypothesis that a mixture would have cumulative antiandrogenic effects. An iprodione dose, that does not significantly affect androgen-dependent morphological end points, was combined with vinclozolin doses (2 x 5 factorial design). Sprague-Dawley rats were dosed by gavage with vinclozolin at 0, 10, 30, 60, and 100 mg/kg/day with and without 50 mg iprodione/kg/day from postnatal day (PND) 23 to 55-57 (n = 8 per group). The age at puberty (preputial separation [PPS]), organ weights, serum hormones, and ex vivo testis steroid hormone production were measured. Vinclozolin delayed PPS, reduced androgen-sensitive organ weights, and increased serum testosterone. The addition of iprodione enhanced the vinclozolin inhibition of PPS (PND 47.5 vs.49.1; two-way ANOVA: iprodione main effect p = 0.0002). The dose response for several reproductive and nonreproductive organ weights was affected in a cumulative manner. In contrast, iprodione antagonized the vinclozolin-induced increase in serum testosterone. These results demonstrate that these fungicides interact on common targets in a tissue-specific manner when coadministered to the pubertal male rat.

Early Adolescent Friendship Selection Based on Externalizing Behavior: the Moderating Role of Pubertal Development. The SNARE Study.

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Franken, Aart; Prinstein, Mitchell J; Dijkstra, Jan Kornelis; Steglich, Christian E G; Harakeh, Zeena; Vollebergh, Wilma A M

2016-11-01

This study examined friendship (de-)selection processes in early adolescence. Pubertal development was examined as a potential moderator. It was expected that pubertal development would be associated with an increased tendency for adolescents to select their friends based on their similarities in externalizing behavior engagement (i.e., delinquency, alcohol use, and tobacco use). Data were used from the first three waves of the SNARE (Social Network Analysis of Risk behavior in Early adolescence) study (N = 1144; 50 % boys; M age  = 12.7; SD = 0.47), including students who entered the first year of secondary school. The hypothesis was tested using Stochastic Actor-Based Modeling in SIENA. While taking the network structure into account, and controlling for peer influence effects, the results supported this hypothesis. Early adolescents with higher pubertal development were as likely as their peers to select friends based on similarity in externalizing behavior and especially likely to remain friends with peers who had a similar level of externalizing behavior, and thus break friendship ties with dissimilar friends in this respect. As early adolescents are actively engaged in reorganizing their social context, adolescents with a higher pubertal development are especially likely to lose friendships with peers who do not engage in externalizing behavior, thus losing an important source of adaptive social control (i.e., friends who do not engage in externalizing behavior).

Effect of timing on the outcomes of 1-phase nonextraction therapy of Class II malocclusion.

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Baccetti, Tiziano; Franchi, Lorenzo; Kim, Ludia H

2009-10-01

The aim of this cephalometric study was to evaluate the role of timing in relation to skeletal maturity on the outcomes of nonextraction comprehensive Class II therapy. Three samples of patients with Class II Division 1 malocclusion were treated with headgear combined with fixed appliances and Class II elastics. Lateral cephalograms were taken of all subjects before therapy (T1) and at an average interval of 6 months after therapy (T2). The first sample (23 subjects) was treated before the pubertal growth spurt, the second sample (24 subjects) received therapy during the pubertal growth spurt, and the third sample (13 subjects) was treated at a postpubertal stage of development. The average T1 to T2 interval was approximately 30 months for all patients, with an average treatment duration of 24 months. Longitudinal observations of a group of 17 subjects with untreated Class II malocclusions were compared with the treated groups at the 3 skeletal maturation intervals with nonparametric statistics. Class II treatment before or during the pubertal growth spurt induced significant favorable skeletal changes (restricted maxillary advancement in prepubertal patients and enhanced mandibular growth in pubertal patients). Patients treated after the pubertal growth spurt had only significant dentoalveolar changes. The greatest amount of dentoskeletal correction of Class II malocclusion with 1-phase nonextraction treatment occurred in patients treated during the pubertal growth spurt.

Endothelial function in pre-pubertal children at risk of developing cardiomyopathy: a new frontier

Directory of Open Access Journals (Sweden)

Aline Cristina Tavares

2012-01-01

Full Text Available Although it is known that obesity, diabetes, and Kawasaki's disease play important roles in systemic inflammation and in the development of both endothelial dysfunction and cardiomyopathy, there is a lack of data regarding the endothelial function of pre-pubertal children suffering from cardiomyopathy. In this study, we performed a systematic review of the literature on pre-pubertal children at risk of developing cardiomyopathy to assess the endothelial function of pre-pubertal children at risk of developing cardiomyopathy. We searched the published literature indexed in PubMed, Bireme and SciELO using the keywords 'endothelial', 'children', 'pediatric' and 'infant' and then compiled a systematic review. The end points were age, the pubertal stage, sex differences, the method used for the endothelial evaluation and the endothelial values themselves. No studies on children with cardiomyopathy were found. Only 11 papers were selected for our complete analysis, where these included reports on the flow-mediated percentage dilatation, the values of which were 9.80±1.80, 5.90±1.29, 4.50±0.70, and 7.10±1.27 for healthy, obese, diabetic and pre-pubertal children with Kawasaki's disease, respectively. There was no significant difference in the dilatation, independent of the endothelium, either among the groups or between the genders for both of the measurements in children; similar results have been found in adolescents and adults. The endothelial function in cardiomyopathic children remains unclear because of the lack of data; nevertheless, the known dysfunctions in children with obesity, type 1 diabetes and Kawasaki's disease may influence the severity of the cardiovascular symptoms, the prognosis, and the mortality rate. The results of this study encourage future research into the consequences of endothelial dysfunction in pre-pubertal children.

Lauric Acid Stimulates Mammary Gland Development of Pubertal Mice through Activation of GPR84 and PI3K/Akt Signaling Pathway.

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Meng, Yingying; Zhang, Jing; Zhang, Fenglin; Ai, Wei; Zhu, Xiaotong; Shu, Gang; Wang, Lina; Gao, Ping; Xi, Qianyun; Zhang, Yongliang; Liang, Xingwei; Jiang, Qingyan; Wang, Songbo

2017-01-11

It has been demonstrated that dietary fat affects pubertal mammary gland development. However, the role of lauric acid (LA) in this process remains unclear. Thus, this study aimed to investigate the effects of LA on mammary gland development in pubertal mice and to explore the underlying mechanism. In vitro, 100 μM LA significantly promoted proliferation of mouse mammary epithelial cell line HC11 by regulating expression of proliferative markers (cyclin D1/3, p21, PCNA). Meanwhile, LA activated the G protein-coupled receptor 84 (GPR84) and PI3K/Akt signaling pathway. In agreement, dietary 1% LA enhanced mammary duct development, increased the expression of GPR84 and cyclin D1, and activated PI3K/Akt in mammary gland of pubertal mice. Furthermore, knockdown of GPR84 or inhibition of PI3K/Akt totally abolished the promotion of HC11 proliferation induced by LA. These results showed that LA stimulated mammary gland development of pubertal mice through activation of GPR84 and PI3K/Akt signaling pathway.

[Craniopharyngioma and Klinefelter syndrome during the pubertal transition: A diagnostic challenge].

Science.gov (United States)

Mocarbel, Yamile; Arébalo de Cross, Graciela; Lebrethon, Marie C; Thiry, Albert; Beckersd, Albert; Valdes-Socin, Hernan

2017-04-01

Craniopharyngioma is the most common pituitary tumor in childhood. It can compromise the pubertal development because of its evolution or treatment. Syndrome of Klinefelter is the most common cause of hipergonadotrophic hypogonadism in males. The concomitant presentation of both entities is extremely low (1/109) and the pathophysiological association is questionned. We present the case of a 18-year-old Belgian patient. He had a diagnosis of craniopharyngioma in childhood and he presented with panhypopituitarism after radiotherapy and surgical treatment. At the age of 14, he started pubertal induction with gonadotropin therapy without clinical response. Asociación de craneofaringioma y síndrome de Klinefelter en la transición puberal: un desafío diagnóstico Craniopharyngioma and Klinefelter syndrome during the pubertal transition: A diagnostic challenge A genetic evaluation confirmed a homogeneous 47, XXY karyotype. Failure of exogenous gonadotropin therapy revealed the hidden association of primary and secondary hypogonadism, demonstrating the importance of the followup and a multidisciplinary approach in these patients. Sociedad Argentina de Pediatría.

[Study on the pathogens correlated to sexually transmitted diseases in 285 pre-pubertal girls with vulvovaginitis in Beijing].

Science.gov (United States)

Liu, Xiao-Yan; Sun, Hong-Mei; Feng, Yan-Ling; Hu, Jin; Zhao, Han-Qing; Zhang, Li-Ya

2007-08-01

To study the relationship between vulvovaginitis in pre-pubertal girls and pathogens as Chlamydia trachomatis (Ct), N. gonorrhoeae (Ng), Mycoplasma, Ureaplasma urealyticum (Uu), Mycoplasma hominis (Mh), M. genitalium (Mg), M. fermentans (Mf) and M. penetrans (Mpe), as well as to find out the proportion of mycoplasma which is correlated to sexually transmitted diseases (STD) and AIDS. METHODS Vulvae swab specimens from 285 pre-pubertal girls with vulvovaginitis (case group) and 128 healthy girls (control group) were collected and detected by nested polymerase chain reaction (nPCR) to identify the existence of pathogens as Ct, Ng, Uu, Mh, Mg, Mf and Mpe. nPCR with both high specificity and sensitivity, would not be influenced by the amount of pathogens in specimens or inactivated during the process of storage or transportation. The rate of detection on pathogens was 59.65% in the 285 specimens from case group including 'one kind of pathogen in one specimen' as 37.54% and 'two kinds' as 16.84% and 'three kinds' as 5.26%. However, in the 128 specimens from control group, the detectable rate of pathogen was 6.25%. Relationships were found between Ng (P vulvovaginitis in pre-pubertal girls. In control group the pathogens were detected from 7 specimens including 5 Uu and 2 Mh. Some of the pathogens were correlated to STD and were important in causing vulvovaginitis in pre-pubertal girls. Vulvovaginitis might have been caused by more than one kind of pathogen in pre-pubertal girls. The locations of Mg, Mf and Ng in outer genital tracts were correlated to seasonal change. Macrolide seemed to be quite effective clinically in treating urogenital tract infection caused by mycoplasma and Ct.

Arthrospira (Spirulina) platensis supplementation affects folliculogenesis, progesterone and ghrelin levels in fattening pre-pubertal gilts

NARCIS (Netherlands)

Abadjieva, Desislava; Nedeva, Radka; Marchev, Yordan; Jordanova, Gergana; Chervenkov, Mihail; Dineva, Julieta; Shimkus, Almantas; Shimkiene, Aldona; Teerds, Katja; Kistanova, Elena

2018-01-01

The aim of the present investigation was to study the effect of Arthrospira (Spirulina) platensis supplemented diet on follicular development and related endocrine parameters, such as estradiol and progesterone levels as well as ghrelin levels in pre-pubertal gilts. Twenty-one 60-day-old Danube

Individual differences in boys' and girls' timing and tempo of puberty: modeling development with nonlinear growth models.

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Marceau, Kristine; Ram, Nilam; Houts, Renate M; Grimm, Kevin J; Susman, Elizabeth J

2011-09-01

Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear mixed-effects models to describe both the timing and tempo of pubertal development in the sample of 364 White boys and 373 White girls measured across 6 years as part of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Individual differences in timing and tempo were extracted with models of logistic growth. Differential relations emerged for how boys' and girls' timing and tempo of development were related to physical characteristics (body mass index, height, and weight) and psychological outcomes (internalizing problems, externalizing problems, and risky sexual behavior). Timing and tempo are associated in boys but not girls. Pubertal timing and tempo are particularly important for predicting psychological outcomes in girls but only sparsely related to boys' psychological outcomes. Results highlight the importance of considering the nonlinear nature of puberty and expand the repertoire of possibilities for examining important aspects of how and when pubertal processes contribute to development.

Brief communication: a proposed osteological method for the estimation of pubertal stage in human skeletal remains.

Science.gov (United States)

Shapland, Fiona; Lewis, Mary E

2013-06-01

Puberty forms an important threshold between childhood and adulthood, but this subject has received little attention in bioarchaeology. The new application of clinical methods to assess pubertal stage in adolescent skeletal remains is explored, concentrating on the development of the mandibular canine, hamate, hand phalanges, iliac crest and distal radius. Initial results from the medieval cemetery of St. Peter's Church, Barton-upon-Humber, England suggest that application of these methods may provide insights into aspects of adolescent development. This analysis indicates that adolescents from this medieval site were entering the pubertal growth spurt at a similar age to their modern counterparts, but that the later stages of pubertal maturation were being significantly delayed, perhaps due to environmental stress. Continued testing and refinement of these methods on living adolescents is still necessary to improve our understanding of their significance and accuracy in predicting pubertal stages. Copyright © 2013 Wiley Periodicals, Inc.

Melatonin and LH secretion patterns in pubertal boys

International Nuclear Information System (INIS)

Fevre, M.; Boyar, R.M.; Rollag, M.D.

1979-01-01

Plasma melatonin and LH were measured at 20 minute intervals for 24 hours in four normal pubertal boys. All four subjects showed a significant augmentation of LH and melatonin during nocturnal sleep. There was also a significant correlation between the LH and melatonin levels (p [fr

Blood spotting on underpants: Case report of urethral prolapse in a pre-pubertal Chinese girl

Directory of Open Access Journals (Sweden)

Hei Yi Wong

2015-05-01

Full Text Available Urethral prolapse is a rare urological condition with non-specific clinical manifestations which is mostly seen in pre-pubertal black girls and postmenopausal woman. The exact etiology still remains unknown. We herein present a case report of urethral mucosa prolapse in a 5 year-old Chinese pre-pubertal girl.

Effects of Habitual Physical Activity and Fitness on Tibial Cortical Bone Mass, Structure and Mass Distribution in Pre-pubertal Boys and Girls: The Look Study.

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Duckham, Rachel L; Rantalainen, Timo; Ducher, Gaele; Hill, Briony; Telford, Richard D; Telford, Rohan M; Daly, Robin M

2016-07-01

Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P girls, but active-fit girls had 6.1 % (P girls, which was likely due to their 6.7 % (P active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.

[A survey of pubertal development in children born with assisted reproductive technology].

Science.gov (United States)

Liu, Zi-Yuan; Wang, Xin-Li; Han, Tong-Yan; Cui, Yun-Pu; Wang, Xue-Mei; Tong, Xiao-Mei; Song, Yi; Wang, Hai-Jun; Li, Song

2017-06-01

To investigate the status of pubertal development in children born with assisted reproductive technology (ART). A retrospective analysis was performed on the pubertal development data of children born with ART in Peking University Third Hospital from 1994 to 2003 (ART group). The data in the cross-sectional study "Reports on the Physical Fitness and Health Research of Chinese School Students in 2010" were used as a control. The age at menarche and the age at spermarche were compared between the two groups. The status of pubertal development in the overweight and obese children in the ART group was evaluated to investigate the correlation between pubertal development and body mass index (BMI). A total of 200 children born with ART were enrolled in this study, and 72 of them (41 males and 31 females) completed the survey (response rate=36.0%). In the ART group, the mean age at spermarche and the mean age at menarche were 13.9 years (95%CI: 13.7-14.3 years) and 12.2 years (95%CI: 11.8-12.6 years), respectively. There were no significant differences in the age at spermarche and the age at menarche between the ART and control groups (P>0.05). In the ART group, there were no significant differences in the age at spermarche and the age at menarche between the overweight and obese children and the normal weight children (P>0.05). There were also no significant differences in overweight rate and obesity rate between the children in the ART group and the adolescents in Beijing (P>0.05). In the ART group, there was no significant correlation between the age at spermarche or menarche and BMI (P>0.05). No delayed or precocious puberty is observed in children born with ART. This is consistent with the normal control data. And there is no significant correlation between pubertal development and BMI in children born with ART.

An unanswered question in pediatric urology: the post pubertal persistence of prepubertal congenital penile curvature correction by tunical plication.

Science.gov (United States)

Ozkuvanci, Ünsal; Ziylan, Orhan; Dönmez, M Irfan; Yucel, Omer Baris; Oktar, Tayfun; Ander, Haluk; Nane, Ismet

2017-01-01

The aim of this study is to analyze post pubertal results of pre pubertal tunica albuginea plication with non-absorbable sutures in the correction of CPC. The files of patients who underwent tunica albuginea plication without incision (dorsal/lateral) were retrospectively reviewed. Patients younger than 13 years of age at the time of operation and older than 14 years of age in November 2015 were included. Patients with a penile curvature of less than 30 degrees & more than 45 degrees and penile/urethral anomalies were excluded. All of the patients underwent surgery followed by circumcision. The mean age of patients at the time of the operation was 9.7 years (range, 6-13 years). The mean degree of ventral penile curvature measured during the operation was 39 degrees while it was 41 degrees in the lateral curvatures. All of the patients were curvature-free at the end of the operation. At the time of the follow-up examination, the mean age was 16.7 years (range, 14-25 years). Six patients had a straight (0-10 degrees) penis during erection and seven patients had recurrent penile curvatures ranging from 30 to 50 degrees. Pre pubertal tunica albuginea plication of congenital penile curvature (30-45 degrees) with non-absorbable sutures performed without incision is a minimal invasive method especially when performed during circumcision. However, recurrence might be observed in half of the patients after puberty. Copyright® by the International Brazilian Journal of Urology.

An unanswered question in pediatric urology: the post pubertal persistence of prepubertal congenital penile curvature correction by tunical plication

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Ünsal Ozkuvanci

Full Text Available ABSTRACT Objective: The aim of this study is to analyze post pubertal results of pre pubertal tunica albuginea plication with non-absorbable sutures in the correction of CPC. Materials and Methods: The files of patients who underwent tunica albuginea plication without incision (dorsal/lateral were retrospectively reviewed. Patients younger than 13 years of age at the time of operation and older than 14 years of age in November 2015 were included. Patients with a penile curvature of less than 30 degrees & more than 45 degrees and penile/urethral anomalies were excluded. All of the patients underwent surgery followed by circumcision. Results: The mean age of patients at the time of the operation was 9.7 years (range, 6-13 years. The mean degree of ventral penile curvature measured during the operation was 39 degrees while it was 41 degrees in the lateral curvatures. All of the patients were curvature-free at the end of the operation. At the time of the follow-up examination, the mean age was 16.7 years (range, 14-25 years. Six patients had a straight (0-10 degrees penis during erection and seven patients had recurrent penile curvatures ranging from 30 to 50 degrees. Conclusion: Pre pubertal tunica albuginea plication of congenital penile curvature (30-45 degrees with non-absorbable sutures performed without incision is a minimal invasive method especially when performed during circumcision. However, recurrence might be observed in half of the patients after puberty.

The influence of chronic conditions and the environment on pubertal development. An example from medieval England.

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Lewis, M E; Shapland, F; Watts, R

2016-03-01

Adolescence is a unique period in human development encompassing sexual maturation (puberty) and the physical and psychological transition into adulthood. It is a crucial time for healthy development and any adverse environmental conditions, poor nutrition, or chronic infection can alter the timing of these physical changes; delaying menarche in girls or the age of peak height velocity in boys. This study explores the impact of chronic illness on the tempo of puberty in 607 adolescent skeletons from medieval England (AD 900-1550). A total of 135 (22.2%) adolescents showed some delay in their pubertal development, and this lag increased with age. Of those with a chronic condition, 40.0% (n=24/60) showed delay compared to only 20.3% (n=111/547) of the non-pathology group. This difference was statistically significant. A binary logistic regression model demonstrated a significant association between increasing delay in pubertal stage attainment with age in the pathology group. This is the first time that chronic conditions have been directly associated with a delay in maturation in the osteological record, using a new method to assess stages of puberty in skeletal remains. Copyright © 2015 Elsevier Inc. All rights reserved.

Insulin resistance in obese pre-pubertal children: Relation to body ...

African Journals Online (AJOL)

Secondary outcome is to determine the frequency of the metabolic syndrome components. Subjects and methods: Twenty-three pre-pubertal obese children were ... oral glucose tolerance testing (OGTT) and DXA scan for body composition.

Physical activity reduces systemic blood pressure and improves early markers of atherosclerosis in pre-pubertal obese children.

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Farpour-Lambert, Nathalie J; Aggoun, Yacine; Marchand, Laetitia M; Martin, Xavier E; Herrmann, François R; Beghetti, Maurice

2009-12-15

The aim of this study was to determine the effects of physical activity on systemic blood pressure (BP) and early markers of atherosclerosis in pre-pubertal obese children. Hypertension and endothelial dysfunction are premature complications of obesity. We performed a 3-month randomized controlled trial with a modified crossover design: 44 pre-pubertal obese children (age 8.9 + or - 1.5 years) were randomly assigned (1:1) to an exercise (n = 22) or a control group (n = 22). We recruited 22 lean children (age 8.5 + or - 1.5 years) for baseline comparison. The exercise group trained 60 min 3 times/week during 3 months, whereas control subjects remained relatively inactive. Then, both groups trained twice/week during 3 months. We assessed changes at 3 and 6 months in office and 24-h BP, arterial intima-media thickness (IMT) and stiffness, endothelial function (flow-mediated dilation), body mass index (BMI), body fat, cardiorespiratory fitness (maximal oxygen consumption [VO(2)max]), physical activity, and biological markers. Obese children had higher BP, arterial stiffness, body weight, BMI, abdominal fat, insulin resistance indexes, and C-reactive protein levels, and lower flow-mediated dilation, VO(2)max, physical activity, and high-density lipoprotein cholesterol levels than lean subjects. At 3 months, we observed significant changes in 24-h systolic BP (exercise -6.9 + or - 13.5 mm Hg vs. control 3.8 + or - 7.9 mm Hg, -0.8 + or - 1.5 standard deviation score [SDS] vs. 0.4 + or - 0.8 SDS), diastolic BP (-0.5 + or - 1.0 SDS vs. 0 + or - 1.4 SDS), hypertension rate (-12% vs. -1%), office BP, BMI z-score, abdominal fat, and VO(2)max. At 6 months, change differences in arterial stiffness and IMT were significant. A regular physical activity program reduces BP, arterial stiffness, and abdominal fat; increases cardiorespiratory fitness; and delays arterial wall remodeling in pre-pubertal obese children. (Effects of Aerobic Exercise Training on Arterial Function and

Growth trajectory and pubertal tempo from birth till final height in a girl with Wolf-Hirschhorn syndrome.

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Siew, Jia Xuan; Yap, Fabian

2018-01-01

Growth anomaly is a prominent feature in Wolf-Hirschhorn syndrome (WHS), a rare congenital disorder caused by variable deletion of chromosome 4p. While growth charts have been developed for WHS patients 0-4 years of age and growth data available for Japanese WHS patients 0-17 years, information on pubertal growth and final height among WHS children remain lacking. Growth hormone (GH) therapy has been reported in two GH-sufficient children with WHS, allowing for pre-puberty catch up growth; however, pubertal growth and final height information was also unavailable. We describe the complete growth journey of a GH-sufficient girl with WHS from birth until final height (FH), in relation to her mid parental height (MPH) and target range (TR). Her growth trajectory and pubertal changes during childhood, when she was treated with growth hormone (GH) from 3 years 8 months old till 6 months post-menarche at age 11 years was fully detailed. Pubertal growth characteristics and FH information in WHS is lacking.While pre-pubertal growth may be improved by GH, GH therapy may not translate to improvement in FH in WHS patients.Longitudinal growth, puberty and FH data of more WHS patients may improve the understanding of growth in its various phases (infancy/childhood/puberty).

A Short-Term Longitudinal Study of Pubertal Change, Gender, and Psychological Well-Being of Mexican Early Adolescents.

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Benjet, Corina; Hernandez-Guzman, Laura

2002-01-01

Studied the role of pubertal development on depression, externalizing behavior problems, self-esteem, and body-image of 951 Mexican early adolescents. Findings show that the acute experience of menarche adversely affected the psychological well-being of girls, specifically in terms of depressive symptomatology. Pubertal change in boys did not…

Serum inhibin B in healthy pubertal and adolescent boys

DEFF Research Database (Denmark)

Andersson, A M; Juul, A; Petersen, J H

1997-01-01

Inhibin B levels were measured in serum from 400 healthy Danish prepubertal, pubertal, and adolescent males, aged 6-20 yr, in a cross-sectional study using a recently developed immunoassay that is specific for inhibin B, the physiologically important inhibin form in men. In addition, serum levels...

Insulin resistance in obese pre-pubertal children: Relation to body ...

African Journals Online (AJOL)

Heba Elsedfy

2014-04-16

Apr 16, 2014 ... of pre-pubertal obese children, and to investigate the relation- .... children P 10 years, HDL-Cholesterol <35 mg/dl) [18]. .... HDL: high density lipoprotein, TG: triglycerides, IFG: impaired fasting glucose, IGT: impaired glucose ...

Candidate gene expression in Bos indicus ovarian tissues: pre-pubertal and post-pubertal heifers in diestrus

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Mayara Morena Del Cambre Amaral Weller

2016-10-01

Full Text Available Growth factors such as bone morphogenetic proteins 6, 7, 15 and two isoforms of transforming growth factor-beta (BMP6, BMP7, BMP15, TGFB1 and TGFB2 and insulin-like growth factor system act as local regulators of ovarian follicular development. To elucidate if these factors as well as others candidate genes such as estrogen receptor 1 (ESR1, growth differentiation factor 9 (GDF9, follicle stimulating hormone receptor (FSHR, luteinizing hormone receptor (LHR, bone morphogenetic protein receptor, type 2 (BMPR2, type 1 insulin-like growth factor receptor (IGFR1, and key steroidogenic enzymes cytochrome P450 aromatase and 3-β-hydroxysteroid dehydrogenase (CYP19A1 and HSD3B1 could modulate or influence diestrus on the onset of puberty in Brahman heifers, their ovarian mRNA expression was measured before and after puberty (luteal phase. Six post-pubertal (POST heifers were euthanized on the luteal phase of their second cycle, confirmed by corpus luteum observation, and six pre-pubertal (PRE heifers were euthanized in the same day. Quantitative real-time PCR analysis showed that the expression of FSHR, BMP7, CYP19A1, IGF1 and IGFR1 mRNA was greater in PRE heifers, when contrasted to POST heifers. The expression of LHR and HSD3B1 was lower in PRE heifers. Differential expression of ovarian genes could be associated with changes in follicular dynamics and different cell populations that have emerged as consequence of puberty and the luteal phase. The emerging hypothesis is that BMP7 and IGF1 are co-expressed and may modulate the expression of FSHR, LHR and IGFR1 and CYP19A1. BMP7 could influence the down-regulation of LHR and up-regulation of FSHR and CYP19A1, which mediates the follicular dynamics in heifer ovaries. Up-regulation of IGF1 expression pre-puberty, compared to post-puberty diestrus, correlates with increased levels FSHR and CYP19A1. Thus, BMP7 and IGF1 may play synergic roles and were predicted to interact, from the expression data (P = 0

Pubertally born neurons and glia are functionally integrated into limbic and hypothalamic circuits of the male Syrian hamster.

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Mohr, Margaret A; Sisk, Cheryl L

2013-03-19

During puberty, the brain goes through extensive remodeling, involving the addition of new neurons and glia to brain regions beyond the canonical neurogenic regions (i.e., dentate gyrus and olfactory bulb), including limbic and hypothalamic cell groups associated with sex-typical behavior. Whether these pubertally born cells become functionally integrated into neural circuits remains unknown. To address this question, we gave male Syrian hamsters daily injections of the cell birthdate marker bromodeoxyuridine throughout puberty (postnatal day 28-49). Half of the animals were housed in enriched environments with access to a running wheel to determine whether enrichment increased the survival of pubertally born cells compared with the control environment. At 4 wk after the last BrdU injection, animals were allowed to interact with a receptive female and were then killed 1 h later. Triple-label immunofluorescence for BrdU, the mature neuron marker neuronal nuclear antigen, and the astrocytic marker glial fibrillary acidic protein revealed that a proportion of pubertally born cells in the medial preoptic area, arcuate nucleus, and medial amygdala differentiate into either mature neurons or astrocytes. Double-label immunofluorescence for BrdU and the protein Fos revealed that a subset of pubertally born cells in these regions is activated during sociosexual behavior, indicative of their functional incorporation into neural circuits. Enrichment affected the survival and activation of pubertally born cells in a brain region-specific manner. These results demonstrate that pubertally born cells located outside of the traditional neurogenic regions differentiate into neurons and glia and become functionally incorporated into neural circuits that subserve sex-typical behaviors.

Comparison of clinical and microbiological features of vulvovaginitis in prepubertal and pubertal girls.

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Yilmaz, Ayse E; Celik, Nurullah; Soylu, Gul; Donmez, Ahsen; Yuksel, Cigdem

2012-07-01

Vulvovaginitisis the most common gynecological problem of childhood. The aim of the study was to determine and compare clinical and microbiological features of vulvovaginitis in prepubertal and adolescent girls. In this retrospective study, the records of patients who were diagnosed with vulvovaginitis between January 2005 and December 2010 in the pediatric outpatient clinic at Fatih University Hospital were retrieved. Information regarding age, symptoms, history of antibiotic use within 1 month prior to presentation, findings on urinalysis, serum antistreptolysin-O levels, and results of urine/vaginal cultures was collected. The records of 112 patients were evaluated, 72 of which were prepubertal (64.2%) and 40 were pubertal (35.7%) at the time of diagnosis. Thirty-eight prepubertal patients (52.7%) had a positive result on vaginal culture, the most commonly encountered microorganism being group A beta-hemolytic streptococcus (15.2%). Culture positivity rate in the pubertal group was 47.5% (19 patients), with Candida albicans being the most frequently isolated microorganism (27.5%). The etiopathogenesis and culture results differ between prepubertal and adolescent girls with vulvovaginitis, which should be taken into consideration in the treatment approach of this disorder. Copyright © 2012. Published by Elsevier B.V.

Impact of Pubertal Development and Physical Activity on Heart Rate Variability in Overweight and Obese Children in Taiwan

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Chen, Su-Ru; Chiu, Hung-Wen; Lee, Yann-Jinn; Sheen, Tzong-Chi; Jeng, Chii

2012-01-01

Child obesity is frequently associated with dysfunction of autonomic nervous system. Children in pubertal development were suggested to be vulnerable to autonomic nervous system problems such as decrease of heart rate variability from dysregulation of metabolic control. This study explored the influence of pubertal development on autonomic nervous…

Insulin resistance in obese children and adolescents: HOMA-IR cut-off levels in the prepubertal and pubertal periods.

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Kurtoğlu, Selim; Hatipoğlu, Nihal; Mazıcıoğlu, Mümtaz; Kendirici, Mustafa; Keskin, Mehmet; Kondolot, Meda

2010-01-01

Childhood obesity is associated with an increased risk for insulin resistance. The underlying mechanism for the physiological increase in insulin levels in puberty is not clearly understood. The aim of the present study was to determine the cut-off values for homeostasis model assessment for insulin resistance (HOMA-IR) in obese children and adolescents according to gender and pubertal status. Two hundred and eight obese children and adolescents (141 girls, 127 boys) aged between 5 and 18 years were included in the study. The children were divided into prepubertal and pubertal groups. A standard oral glucose tolerance test (OGTT) was carried out in all children. A total insulin level exceeding 300 μU/mL in the blood samples, collected during the test period, was taken as the insulin resistance criterion. Cut-off values for HOMA-IR were calculated by receiver operating characteristic (ROC) analysis. In the prepubertal period, the rate of insulin resistance was found to be 37% in boys and 27.8% in girls,while in the pubertal period, this rate was 61.7% in boys and 66.7% in girls. HOMA-IR cut-off values for insulin resistance in the prepubertal period were calculated to be 2.67 (sensitivity 88.2%, specificity 65.5%) in boys and 2.22 (sensitivity 100%, specificity 42.3%) in girls, and in the pubertal period, they were 5.22 (sensitivity 56%, specificity 93.3%) in boys and 3.82 (sensitivity 77.1%, specificity 71.4%) in girls. Since gender, obesity and pubertal status are factors affecting insulin resistance, cut-off values which depend on gender and pubertal status, should be used in evaluation of insulin resistance.

Elevated serum IGF-I, but unaltered sex steroid levels, in healthy boys with pubertal gynaecomastia

DEFF Research Database (Denmark)

Mieritz, Mikkel G; Sorensen, Kaspar; Aksglaede, Lise

2014-01-01

OBJECTIVE: Pubertal gynaecomastia is a very common condition. Although the underlying aetiology is poorly understood, it is generally accepted that excess of oestrogens and deficit of androgens are involved in the pathogenesis. Furthermore, adiposity as well as the GH/IGF-I axis may play a role....... In this study, we elucidate the association of adiposity and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), testosterone, oestrogen, IGF-I and IGFBP-3 with the presence of pubertal gynaecomastia in a large cohort of healthy boys. PATIENTS: A total...... of 501 healthy Danish school boys (aged 6·1-19·8 year) from the COPENHAGEN Puberty Study. MEASUREMENTS: Anthropometry and pubertal stages (PH1-6 and G1-5) were evaluated, and the presence of gynaecomastia was assessed. Body fat percentage was calculated by means of four skin folds and impedance...

Prenatal androgen excess programs metabolic derangements in pubertal female rats.

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Yan, Xiaonan; Dai, Xiaonan; Wang, Jing; Zhao, Nannan; Cui, Yugui; Liu, Jiayin

2013-04-01

Owing to the heterogeneity in the clinical symptoms of polycystic ovary syndrome (PCOS), the early pathophysiological mechanisms of PCOS remain unclear. Clinical, experimental, and genetic evidence supports an interaction between genetic susceptibility and the influence of maternal environment in the pathogenesis of PCOS. To determine whether prenatal androgen exposure induced PCOS-related metabolic derangements during pubertal development, we administrated 5α-dihydrotestosterone (DHT) in pregnant rats and observed their female offspring from postnatal 4 to 8 weeks. The prenatally androgenized (PNA) rats exhibited more numerous total follicles, cystic follicles, and atretic follicles than the controls. Fasting glucose, insulin, leptin levels, and homeostatic model assessment for insulin resistance were elevated in the PNA rats at the age of 5-8 weeks. Following intraperitoneal glucose tolerance tests, glucose and insulin levels did not differ between two groups; however, the PNA rats showed significantly higher 30- and 60-min glucose levels than the controls after insulin stimulation during 5-8 weeks. In addition, prenatal DHT treatment significantly decreased insulin-stimulated phosphorylation of AKT in the skeletal muscles of 6-week-old PNA rats. The abundance of IR substrate 1 (IRS1) and IRS2 was decreased in the skeletal muscles and liver after stimulation with insulin in the PNA group, whereas phosphorylation of insulin-signaling proteins was unaltered in the adipose tissue. These findings validate the contribution of prenatal androgen excess to metabolic derangements in pubertal female rats, and the impaired insulin signaling through IRS and AKT may result in the peripheral insulin resistance during pubertal development.

Ovarian function following pelvic irradiation in prepubertal and pubertal girls and young adult women

International Nuclear Information System (INIS)

Schuck, A.; Hamelmann, V.; Braemswig, J.H.

2005-01-01

Purpose: To analyze the effect of pelvic radiotherapy on ovarian function in prepubertal and pubertal girls and young adult women. Patients and methods: In a retrospective monoinstitutional analysis, patients 15 Gy to the ovaries developed hormone failure. In one case of a patient receiving an ovarian dose of 15 Gy, hormone failure was not found. In case of pelvic irradiation excluding at least one ovary, approximately half of the patients developed ovarian dysfunction, probably also due to the effects of polychemotherapy. (orig.)

[Pubertal maturation, physical self-esteem and sexuality in a sample of French adolescents].

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Potard, C; Courtois, R; Clarisse, R; Le Floc'h, N; Thomine, M; Réveillère, C

2016-04-01

The aim of this study was to explore the links between pubertal maturation, physical self-esteem and sexuality in adolescence, differentiating between boys and girls. The sample was comprised of 312 French secondary school children (seventh and ninth grades); 52.6 % (n=164) of whom were girls. Participants answered three self-evaluation questionnaires: the scale of sexuality (interests, emotions, relationships: IERS) in prime adolescence (12 to 15 years); (b) the self-administered rating scale for pubertal development and (c) the Physical Self-Description Questionnaire (PSDQ). Pubertal maturation was associated with higher scores on "Flirting with the aim of having sexual relations" and "Going out with someone", and a drop in overall and physical self-esteem, mainly in socially valued domains, namely "Body fat" for girls, and "Strength" and "Health" for boys. Overall physical self-esteem was associated with "Going out with someone" and "Flirting with the aim of having sexual relations" in boys. Physical changes at puberty induce two distinct trends in adolescents: sexual exploration and discovery (genitalized body), and self-depreciation (social body). Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Sulforaphane attenuates di-N-butylphthalate-induced reproductive damage in pubertal mice: Involvement of the Nrf2-antioxidant system.

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Jiang, Xu-Ping; Tang, Jing-Yuan; Xu, Zhen; Han, Peng; Qin, Zhi-Qiang; Yang, Cheng-di; Wang, Shang-Qian; Tang, Min; Wang, Wei; Qin, Chao; Xu, Yang; Shen, Bai-Xin; Zhou, Wei-Min; Zhang, Wei

2017-07-01

di-N-butylphthalate (DBP) is a ubiquitous environmental pollutant used for plastic coating and in the cosmetics industry. It has toxic effects on body health, especially the male reproductive system. Here, we investigated the effects of DBP on the male reproductive system of pubertal mice and explored the protective role of sulforaphane (SFN). The results showed that DBP significantly reduced the anogenital distance, testicular weight, sperm count and motility, and plasma and testicular testosterone levels and significantly increased the oxidative stress, sperm abnormalities, and testicular cell apoptosis. SFN supplementation ameliorated these effects. After DBP stimulation, the transcription factor nuclear factor erythroid-related factor 2 (Nrf2) was adaptively increased together with its target genes, such as HO-1 and NQO1. Upregulation of Nrf2 by SFN reduced the DBP-mediated intracellular oxidative toxicity and also increased testosterone secretion and spermatogenesis, which were decreased by DBP. These findings indicate that SFN can attenuate DBP-induced reproductive damage in pubertal mice via Nrf2-associated pathways. © 2017 Wiley Periodicals, Inc.

A pre-pubertal girl with giant juvenile fibroadenoma: A rare case report

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Kumar Gaurav

2015-01-01

Conclusion: Through this case we want to emphasize that these giant benign neoplasms should be suspected in any pre-pubertal girl with breast lump and should always be treated with breast conserving surgery.

Polymorphisms in JMJD1C are associated with pubertal onset in boys and reproductive function in men

DEFF Research Database (Denmark)

Mørup, Nina; Busch, Alexander Siegfried; Bang, Anne Kirstine

2017-01-01

single nucleotide polymorphisms (SNPs) nearby JMJD1C are associated with pubertal onset in boys and with male reproduction. 671 peri-pubertal boys, 1,027 young men, 315 fertile men, and 252 infertile men were genotyped for two JMJD1C SNPs (rs7910927 and rs10822184). rs7910927 and rs10822184 showed high...... linkage. Boys with the rs7910927 TT genotype entered puberty 3.6 months earlier than their peers (p = 2.5 × 10-2). In young men, the number of T alleles was associated with decreased levels of SHBG, follicle-stimulating hormone (FSH), testosterone, and testosterone x luteinizing hormone, as well...... on the age at pubertal onset in boys as well as levels of reproductive hormones and testis size in men, emphasizing the relationship between JMJD1C and reproductive functions....

Effect of Leaked Radiation from Microwave Oven on Bone Marrow of Male Rats in Pre and Post Pubertal Stage

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G Jelodar

2011-01-01

Full Text Available Introduction: Increasing hematological diseases along with increased use of microwaves in different systems proposed possible correlation between them. Age of exposure to wave is also an important factor. This study was conducted to evaluate the effect of radiation leakaged from microwave oven on hemopoitic bone marrow cells at pre and post pubertal. Methods: Fourteen male mature (2 months old and 14 male immature rats(one month old were randomly divided in to four groups (control and test. Test groups were exposed, three times a day each time 30 min for 60 days, to microwaves produced by microwave oven. After sixty days, animals were sacrified and bone marrow samples were collected from femural bones. Percent of variose cells type and their morphology were evaluated in 500 cells of each smear. Results: exposure to microwave did not exert visible morphological alteration. In the immature experimental group significant decrease in percent of basophilic rubricyte, polychromatic rubricyte, meta rubricyte and all the erythroid cell types observed(P<0.05, whereas, meta myelocyte, notrophilic band, total myeloid cell types and prolifrative cells, other cell types and the myeloid/erythroid ratio significantly increased(P<0.05. In the mature group, however, a significant decrease in percent of meta rubricyte and myelocyte cells observed(P<0.05, although prolifrative cells and all other cell types were significantly increasing in this group. Conclusion: In conclusion, the radiation leaked from microwave oven in the experimental conditions had no effect on the morphology of hemopoitic bone marrow cells, though the number of these cells was altered especially in immature group.

Tamoxifen therapy for the management of pubertal gynecomastia: a systematic review

NARCIS (Netherlands)

Lapid, Oren; van Wingerden, Jan J.; Perlemuter, Leon

2013-01-01

Objective: A systematic review to assess the efficacy of tamoxifen in the management of idiopathic pubertal gynecomastia. Data sources: Searches were conducted using the databases of Medline (search engine PubMed) and Web of Science (R). Study selection: Studies reporting the use of Tamoxifen for

Investigation of pre-pubertal sex differences in wheel running and social behavior in three mouse strains

OpenAIRE

Gordon, Elizabeth A.; Corbitt, Cynthia

2015-01-01

Sex differences in social behaviors exist in mammals during adulthood, and further evidence suggests that sex differences in behavior are present before sexual maturity. In order to model behavioral disorders in animals, it is important to assess baseline sex-related behavioral differences, especially when studying disorders for which sex-related behavioral effects are expected. We investigated the effect of sex on behavior in 3 strains of pre-pubertal mice (C57BL/6, CFW, and CF1) using a whe...

Pubertal maturation and sex steroids are related to alcohol use in adolescents

NARCIS (Netherlands)

Water, E. de; Braams, B.R.; Crone, E.A.; Peper, J.S.

2013-01-01

Adolescents often show risk-taking behavior, including experimentation with alcohol. Previous studies have shown that advanced pubertal maturation is related to increased alcohol use in adolescents, even when controlling for age. Little is known about the underlying mechanisms of this relation

Giant fibroadenoma of the breast in a pre-pubertal girl: a case report

Directory of Open Access Journals (Sweden)

Sunder Goyal

2014-02-01

Full Text Available Juvenile fibroadenoma comprises about 4% of the total fibroadenomas. The incidence of giant juvenile fibroadenomas is merely 0.5% of all the fibroadenomas. Bilateral giant juvenile fibroadenomas are extremely rare. We are presenting a case of giant juvenile fibroadenomas in an 11-year-old pre-pubertal girl. The diagnosis was made on fine-needle aspiration cytology which was confirmed on histopathology. As these tumors are mostly benign, breast-conserving surgery is done so that patient can lead a normal life without psychological trauma.-----------------------------------Cite this article as: Goyal S, Garg G, Narang S. Giant fibroadenoma of the breast in a pre-pubertal girl: a case report. Int J Cancer Ther Oncol 2014; 2(1:020113.DOI: http://dx.doi.org/10.14319/ijcto.0201.13

Contributions of Function-Altering Variants in Genes Implicated in Pubertal Timing and Body Mass for Self-Limited Delayed Puberty.

Science.gov (United States)

Howard, Sasha R; Guasti, Leonardo; Poliandri, Ariel; David, Alessia; Cabrera, Claudia P; Barnes, Michael R; Wehkalampi, Karoliina; O'Rahilly, Stephen; Aiken, Catherine E; Coll, Anthony P; Ma, Marcella; Rimmington, Debra; Yeo, Giles S H; Dunkel, Leo

2018-02-01

Self-limited delayed puberty (DP) is often associated with a delay in physical maturation, but although highly heritable the causal genetic factors remain elusive. Genome-wide association studies of the timing of puberty have identified multiple loci for age at menarche in females and voice break in males, particularly in pathways controlling energy balance. We sought to assess the contribution of rare variants in such genes to the phenotype of familial DP. We performed whole-exome sequencing in 67 pedigrees (125 individuals with DP and 35 unaffected controls) from our unique cohort of familial self-limited DP. Using a whole-exome sequencing filtering pipeline one candidate gene [fat mass and obesity-associated gene (FTO)] was identified. In silico, in vitro, and mouse model studies were performed to investigate the pathogenicity of FTO variants and timing of puberty in FTO+/- mice. We identified potentially pathogenic, rare variants in genes in linkage disequilibrium with genome-wide association studies of age at menarche loci in 283 genes. Of these, five genes were implicated in the control of body mass. After filtering for segregation with trait, one candidate, FTO, was retained. Two FTO variants, found in 14 affected individuals from three families, were also associated with leanness in these patients with DP. One variant (p.Leu44Val) demonstrated altered demethylation activity of the mutant protein in vitro. Fto+/- mice displayed a significantly delayed timing of pubertal onset (P puberty in the general population may contribute to the pathogenesis of self-limited DP. Copyright © 2017 Endocrine Society

Serum inhibin B in healthy pubertal and adolescent boys

DEFF Research Database (Denmark)

Andersson, A M; Juul, A; Petersen, J H

1997-01-01

correlated strongly with age, and when the effect of age was taken into account, only the partial correlation between inhibin B and LH/testosterone remained statistically significant. At stage II of puberty, the positive partial correlation between inhibin B and LH/testosterone was still present. At stage......Inhibin B levels were measured in serum from 400 healthy Danish prepubertal, pubertal, and adolescent males, aged 6-20 yr, in a cross-sectional study using a recently developed immunoassay that is specific for inhibin B, the physiologically important inhibin form in men. In addition, serum levels...... of FSH, LH, testosterone, and estradiol levels were measured. Serum levels of inhibin B, FSH, LH, testosterone, and estradiol all increased significantly between stages I and II of puberty. From stage II of puberty the inhibin B level was relatively constant, whereas the FSH level continued to increase...

Prenatal androgen excess enhances stimulation of the GNRH pulse in pubertal female rats.

Science.gov (United States)

Yan, Xiaonan; Yuan, Chun; Zhao, Nannan; Cui, Yugui; Liu, Jiayin

2014-07-01

In adolescent girls with polycystic ovary syndrome (PCOS), neuroendocrine derangements manifest after the onset of puberty, characterized by rapid LH pulse frequency. The early mechanism underlying the pubertal regulation of the GNRH/LH pulsatile release in adolescents with PCOS remains uncertain. To determine the effects of prenatal androgen exposure on the activation of GNRH neurons and generation of LH pulse at puberty, we administrated 5α-dihydrotestosterone to pregnant rats and observed serum LH levels and expression of hypothalamic genes in female offspring from postnatal 4 to 8 weeks. The 6-week-old prenatally androgenized (PNA) female rats exhibited an increase in LH pulse frequency. The hypothalamic expression of neurokinin B (Nkb (Tac2)) and Lepr mRNA levels in PNA rats increased remarkably before puberty and remained high during puberty, whereas elevated Kiss1 mRNA levels were detected only after the onset of puberty. Exogenous kisspeptin, NK3R agonist, and leptin triggered tonic stimulation of GNRH neurons and increased LH secretion in 6-week-old PNA rats. Leptin upregulated Kiss1 mRNA levels in the hypothalamus of pubertal PNA rats; however, pretreatment with a kisspeptin antagonist failed to suppress the elevated serum LH stimulated by leptin, indicating that the stimulatory effects of leptin may be conveyed indirectly to GNRH neurons via other neural components within the GNRH neuronal network, rather than through the kisspeptin-GPR54 pathway. These findings validate the hypotheses that NKB and leptin play an essential role in the activation of GNRH neurons and initiation of increased LH pulse frequency in PNA female rats at puberty and that kisspeptin may coordinate their stimulatory effects on LH release. © 2014 Society for Endocrinology.

Salivary testosterone concentrations in pubertal ICSI boys compared with spontaneously conceived boys

NARCIS (Netherlands)

Belva, F.; Bonduelle, M.; Schiettecatte, J.; Tournaye, H.; Painter, R. C.; Devroey, P.; de Schepper, J.

2011-01-01

BACKGROUND: To date, no data exist about Leydig cell function of pubertal boys born after ICSI. To evaluate a potential risk of gonadal dysfunction in children born from fathers with compromised fertility, testicular function was assessed by the measurement of salivary testosterone. METHODS: Morning

Perinatal testosterone contributes to mid-to-post pubertal sex differences in risk for binge eating in male and female rats.

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Culbert, Kristen M; Sinclair, Elaine B; Hildebrandt, Britny A; Klump, Kelly L; Sisk, Cheryl L

2018-02-01

Exposure to testosterone early in life may contribute to sex differences and pubertal changes in risk for eating pathology (i.e., females > males, after pubertal onset). Specifically, perinatal testosterone permanently alters brain structure/function and drives the masculinization of several sex-differentiated behaviors. However, the effects of perinatal testosterone are often not evident until puberty when increases in gonadal hormones activate the expression of sex typical behavior, including eating behaviors (e.g., chow intake; saccharin preference) in rodents. Despite perinatal testosterone's masculinizing effects on general feeding behavior, it remains unknown if perinatal testosterone exposure contributes to sex differences in pathological eating. The current study addressed this gap by examining whether perinatal testosterone exposure decreases risk for binge eating proneness after pubertal onset in male and female rats. Sprague-Dawley rats (n = 40 oil-treated control females; n = 39 testosterone-treated females; n = 40 oil-treated control males) were followed longitudinally across pre-to-early puberty, mid-to-late puberty, and adulthood. The binge eating prone (BEP)/binge eating resistant (BER) rodent model was used to identify individual differences in binge eating proneness across the dimensional spectrum. As expected, testosterone-treated females and control males showed masculinized (i.e., lower) risk for binge eating as compared to control females, but only after midpuberty. These animal data are significant in suggesting that perinatal testosterone exposure may protect against binge eating and underlie sex differences in binge eating prevalence during and after puberty. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Prediction of basal metabolic rate in obese children and adolescents considering pubertal stages and anthropometric characteristics or body composition.

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Lazzer, S; Patrizi, A; De Col, A; Saezza, A; Sartorio, A

2014-06-01

To develop and crossvalidate new equations for predicting basal metabolic rate (BMR) in obese children and adolescents in relation to pubertal stages, anthropometric characteristics or body composition. A total of 1696 obese Caucasian children and adolescents (mean body mass index z-score: 3.5±0.8) participated in this study. BMR was determined by indirect calorimetry and fat-free mass (FFM) and fat mass (FM) by bioelectrical impedance analysis. Equations were derived by stepwise multiple regression analysis using a calibration cohort of 848 subjects, and the equations were crossvalidated with a Bland and Altman method in the remaining 848 subjects. Two new specific equations based on gender (1: males; 0: females), pubertal stages (from 1 to 5, assessed according Marshall & Tanner methods) and body weight (BW, kg), stature (m) or body composition (kg) were generated as follows: (1) BMR=(BW × 0.044)+(stature × 2.836)-(pubertal stage × 0.148)+(gender × 0.781)-0.551 (adjusted coefficient of determination (R(2)adj)= 0.69 and root mean squared error (RMSE)=0.954 MJ); (2) BMR=(FFM × 0.082)+(FM × 0.037)-(pubertal stage × 0.125)+(gender × 0.706)+2.528 (R(2)adj= 0.70 and RMSE=0.943 MJ). In the crossvalidation group, mean-predicted BMR was not significantly different from the mean-measured BMR (MBMR) for all children and adolescents, as well as for boys and girls (differenceBMR was predicted accurately (90-110% of MBMR) in 67% of subjects. The new prediction equations considering the pubertal stages allow an accurate and more appropriate (vs equations using chronological age) estimation of BMR in obese children and adolescents.

Longitudinal change in the neural bases of adolescent social self-evaluations: effects of age and pubertal development.

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Pfeifer, Jennifer H; Kahn, Lauren E; Merchant, Junaid S; Peake, Shannon J; Veroude, Kim; Masten, Carrie L; Lieberman, Matthew D; Mazziotta, John C; Dapretto, Mirella

2013-04-24

Self-evaluations undergo significant transformation during early adolescence, developing in parallel with the heightened complexity of teenagers' social worlds. Intuitive theories of adolescent development, based in part on animal work, suggest that puberty is associated with neural-level changes that facilitate a "social reorientation" (Nelson et al., 2005). However, direct tests of this hypothesis using neuroimaging are limited in humans. This longitudinal fMRI study examined neurodevelopmental trajectories associated with puberty, self-evaluations, and the presumed social reorientation during the transition from childhood to adolescence. Participants (N = 27, mean age = 10.1 and 13.1 years at time points one and two, respectively) engaged in trait evaluations of two targets (the self and a familiar fictional other), across two domains of competence (social and academic). Responses in ventromedial PFC increased with both age and pubertal development during self-evaluations in the social domain, but not in the academic domain. These results suggest that changes in social self-evaluations are intimately connected with biology, not just peer contexts, and provide important empirical support for the relationship between neurodevelopment, puberty, and social functioning.

Treatment timing of MARA and fixed appliance therapy of Class II malocclusion.

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Ghislanzoni, Luis Tomas Huanca; Baccetti, Tiziano; Toll, Douglas; Defraia, Efisio; McNamara, James A; Franchi, Lorenzo

2013-06-01

The objective of this study is to evaluate the effect of timing on Mandibular Anterior Repositioning Appliance (MARA) and fixed appliance treatment of Class II malocclusion in a prospective clinical trial. The treated sample consisted of 51 consecutively treated patients at prepubertal (n = 21), pubertal (n = 15), and postpubertal (n = 15) stages of development. Control groups for the three treated groups were generated from growth data of untreated Class II subjects. Lateral cephalograms were digitized and superimposed via cephalometric software at T1 (pre-treatment) and T2 (after comprehensive treatment). The T1-T2 changes in the treated groups were compared to those in their corresponding control groups with Mann-Whitney tests with Bonferroni correction. Mandibular elongation was greater at the pubertal stage (Co-Gn +2.6 mm, with respect to controls). Headgear effect on the maxilla was greater in the pre-peak sample (Co-A -1.9 mm, with respect to controls). Dentoalveolar compensations (proclination of lower incisors, extrusion and mesialization of lower molars, and reduction in the overbite) were significant in the pre-peak and post-peak groups. Optimal timing for Class II treatment with MARA appliance is at the pubertal growth spurt, with enhanced mandibular skeletal changes and minimal dentoalveolar compensations.

Treatment timing for an orthopedic approach to patients with increased vertical dimension.

Science.gov (United States)

Baccetti, Tiziano; Franchi, Lorenzo; Schulz, Scott O; McNamara, James A

2008-01-01

The aim of this study was to investigate the role of treatment timing on the effectiveness of vertical-pull chincup (V-PCC) therapy in conjunction with a bonded rapid maxillary expander (RME) in growing subjects with mild-to-severe hyperdivergent facial patterns. The records of 39 subjects treated with a bonded RME combined with a V-PCC were compared with 29 untreated subjects with similar vertical skeletal disharmonies. Lateral cephalograms were analyzed before (T1) and after treatment or observation (T2). Both the treated and the untreated samples were divided into prepubertal and pubertal groups on the basis of cervical vertebral maturation (prepubertal treated group, 21 subjects; pubertal treated group, 18 subjects; prepubertal control group, 15 subjects; pubertal control group, 14 subjects). Mean change differences from T2 to T1 were compared in the 2 prepubertal and the 2 pubertal groups with independent-sample t tests. No statistically significant differences between the 2 prepubertal groups were found for any cephalometric skeletal measures from T1 to T2. When compared with the untreated pubertal sample, the group treated with the RME and V-PCC at puberty showed a statistically significant reduction in the inclination of the mandibular plane to the Frankfort horizontal (-2.2 mm), a statistically significant reduction in the inclination of the condylar axis to the mandibular plane (-2.2 degrees), and statistically significant supplementary growth of the mandibular ramus (1.7 mm). Treatment of increased vertical dimension with the RME and V-PCC protocol appears to produce better results during the pubertal growth spurt than before puberty, although the absolute amount of correction in the vertical skeletal parameters is limited.

Total pubertal growth in patients with juvenile idiopathic arthritis treated with growth hormone: analysis of a single center.

Science.gov (United States)

Bechtold, S; Beyerlein, A; Ripperger, P; Roeb, J; Dalla Pozza, R; Häfner, R; Haas, J P; Schmidt, H

2012-10-01

Growth failure is a permanent sequelae in juvenile idiopathic arthritis (JIA). The aim of the study was to compare pubertal growth in control and growth hormone (GH) treated JIA subjects. 64 children with JIA at a mean age of 10.38 ± 2.80 years were enrolled and followed until final height (measured in standard deviation (SD) scores). 39 children (20 m) received GH therapy and 24 (9 m) served as controls. GH dose was 0.33 mg/kg/week. Linear regression analysis was performed to identify factors influencing total pubertal growth. Mean total pubertal growth was 21.1 ± 1.3 cm (mean ± SD) in GH treated JIA patients and 13.8 ± 1.5 cm in controls. Final height was significantly higher with GH treatment (-1.67 ± 1.20 SD) compared to controls (-3.20 ± 1.84 SD). Linear regression model identified age at onset of puberty (ß=-4.2,CI: -5.9, -2.6 in controls and ß=-2.3,CI: -3.6, -1.1 in GH treated) as the main factor for total pubertal growth. Final height SDS was determined by the difference to target height at onset of puberty (ß=-0.59;CI: -0.80, -0.37 in controls and ß=-0.30,CI: -0.52, -0.08 in GH treated), age at onset of puberty (ß=0.47;CI:0.02,0.93 in controls and 0.23;CI: -0.00,0.46 in GH treated) and height gain during puberty (ß=0.13;CI:0.05,0.21 in controls and ß=0.11;CI:0.07,0.16 in GH treated). Total pubertal growth in JIA patients treated with GH was increased by a factor of 1.5 greater in comparison to controls leading to a significantly better final height. To maximize final height GH treatment should be initiated early to reduce the height deficit at onset of puberty. Copyright © 2012 Elsevier Ltd. All rights reserved.

Relationships between urinary biomarkers of phytoestrogens, phthalates, phenols, and pubertal stages in girls

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Chakraborty TR

2012-01-01

Full Text Available Tandra R Chakraborty1, Eilliut Alicea1, Sanjoy Chakraborty21Department of Biology, Adelphi University, One South Avenue, Garden City; 2Department of Biological Sciences, New York City College of Technology, New York, NY, USAAbstract: Phytoestrogens, phthalates, and phenols are estrogen-disrupting chemicals that have a pronounced effect at puberty. They are exogenous chemicals that are either plant-derived or man-made, and can alter the functions of the endocrine system and cause various health defects by interfering with the synthesis, metabolism, binding, or cellular responses of natural estrogens. Phytoestrogens, phthalates, and phenols are some of the potent estrogens detectable in urine. Phytoestrogens are plant-derived xenestrogens found in a wide variety of food products, like soy-based food, beverages, several fruits, and vegetables. Exposure to phytoestrogens can delay breast development and further lead to precocious puberty. The effect of phytoestrogens is mediated through estrogen receptors α and β or by binding with early immediate genes, such as jun and fos. Phthalates are multifunctional synthetic chemicals used in plastics, polyvinyl chloride products, cosmetics, hair spray, and children's toys. Phthalates have been shown to cause defeminization, thelarche, precocious puberty, and an increase in breast and pubic hair in pubertal girls. However, reports are also available that show no association of phthalates with precocious puberty in girls. Phthalates can act through a receptor-mediated signaling pathway or affect the production of luteinizing hormone and follicle-stimulating hormone that has a direct effect on estrogen formation. Phenols like bisphenol A are industrial chemicals used mainly in the manufacture of polycarbonates and plastic materials. Bisphenol A has been shown to cause precocious puberty and earlier menarche in pubertal girls. Reports suggest that the neurotoxic effect of bisphenol A can be mediated either by

Pubertal development, physical self-perception, and motivation toward physical activity in girls.

Science.gov (United States)

Labbrozzi, Dina; Robazza, Claudio; Bertollo, Maurizio; Bucci, Ines; Bortoli, Laura

2013-08-01

We examined the differences in physical self-perception and motivation toward physical activity in early- and mid-adolescent girls. Body Mass Index (BMI) and pubertal status, assessed by means of the Tanner scale, were collected in 11-year-old (n=74) and 13-year-old girls (n=60). The assessment included six scales from the Physical Self-Description Questionnaire, the Physical Activity Enjoyment Scale, and the Situational Intrinsic Motivation Scale. Age differences emerged, with older girls showing a poorer physical perception and lower scores in intrinsic motivation and enjoyment of physical activity. In the subsample of 11-year-olds, findings showed that more developed girls reported a poorer physical perception on the scales of body fat, global physical self-concept, and appearance, and a lower score in the PACES positive scale. Results underscore the need to promote interventions aimed at encouraging active lifestyles among children and adolescent girls, in order to prevent overweight prior to pubertal onset. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

IPRODIONE DELAYS MALE RAT PUBERTAL DEVELOPMENT, REDUCING SERUM TESTOSTERONE AND EX VIVO TESTOSTERONE PRODUCTION

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Iprodione (IPRO) is a dichlorophenyl dicarboximide fungicide similar to the androgen receptor (AR) antagonist vinclozolin. The current studies were designed to determine if IPRO would delay male rat pubertal development like vinclozolin and to identify the mechanism(s) of action...

Pubertal induction in hypogonadism: Current approaches including use of gonadotrophins.

Science.gov (United States)

Zacharin, Margaret

2015-06-01

Primary disorders of the gonad or those secondary to abnormalities of the hypothalamic pituitary axis result in hypogonadism. The range of health problems of childhood and adolescence that affect this axis has increased, as most children now survive chronic illness, but many have persisting deficits in gonadal function as a result of their underlying condition or its treatment. An integrated approach to hormone replacement is needed to optimize adult hormonal and bone health, and to offer opportunities for fertility induction and preservation that were not considered possible in the past. Timing of presentation ranges from birth, with disorders of sexual development, through adolescent pubertal failure, to adult fertility problems. This review addresses diagnosis and management of hypogonadism and focuses on new management strategies to address current concerns with fertility preservation. These include Turner syndrome, and fertility presevation prior to childhood cancer treatment. New strategies for male hormone replacement therapy that may impinge upon future fertility are emphasized. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pubertal Development and Thyroid Function in Intact Juvenile Rats Exposed to 3-Nitro-1,2,4-Trazol-5-One (NTO), February-June 2012

Science.gov (United States)

2014-02-01

vivo effects on androgen-dependent tissues in young rats (i.e., prochloraz) similar to the effects of NTO in the present study have feminized male...the potential to interact with the endocrine system in vivo by identifying effects on pubertal development and thyroid function in the intact juvenile...estrogen or thyroid active compound under the test conditions. The observed testicular toxicity and the effects on the androgen-dependent reproductive

Examination of US puberty-timing data from 1940 to 1994 for secular trends

DEFF Research Database (Denmark)

Euling, Susan Y; Herman-Giddens, Marcia E; Lee, Peter A

2008-01-01

or girls. A majority of the panelists agreed that data are sufficient to suggest a trend toward an earlier breast development onset and menarche in girls but not for other female pubertal markers. A minority of panelists concluded that the current data on girls' puberty timing for any marker...... are insufficient. Almost all panelists concluded, on the basis of few studies and reliability issues of some male puberty markers, that current data for boys are insufficient to evaluate secular trends in male pubertal development. The panel agreed that altered puberty timing should be considered an adverse effect......Whether children, especially girls, are entering and progressing through puberty earlier today than in the mid-1900s has been debated. Secular trend analysis, based on available data, is limited by data comparability among studies in different populations, in different periods of time, and using...

Perception regarding pubertal changes among rural adolescent boys of Haryana: A school based study

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Vinod Chayal

2016-06-01

Full Text Available Background: Adolescence is a transition phase through which a child matures into an adult. The physical changes in the human body are from infant to child to adolescence to adult to old age.  All phases of life behave like a coin with both good and bad facets attached to each phase of life. Aims & Objectives:  1. To study perception and awareness regarding pubertal changes among school going adolescent boys. 2. To study the association between education and perceived pubertal problems among study subjects. Material & Methods: The study was conducted among male students of senior secondary schools of community development block Beri in one year. The study universe comprised of students in middle and late adolescence (aged 14-18 years studying in 9th to 12th classes of the senior secondary schools in the area. A total of 1000 male students were selected from these schools which were more than the required sample size of 891. Results: The study found that 42.66% students and a half (50% of students of class 9th & 10th and class 11th & 12th respectively considered that pubertal changes as a normal phenomenon. The majority of students admitted practicing masturbation and felt shy and guilty for practicing masturbation, also students felt fatigued after night emission. Conclusions: The study concludes that adolescent’s sexuality which often causes controversy and concern among adults is least discussed with them during adolescence. The reasons for this may be many, including moral grounds or because of concomitant health risks and threats to wellbeing.

The relationship between pubertal gynecomastia, prostate specific antigen, free androgen index, SHBG and sex steroids.

Science.gov (United States)

Kilic, Mustafa; Kanbur, Nuray; Derman, Orhan; Akgül, Sinem; Kutluk, Tezer

2011-01-01

To investigate the relationships between pubertal gynecomastia, prostate-specific antigen (PSA), free androgen index (FAI), sex hormone-binding globulin (SHBG) and sex steroids. A total of 61 male adolescents (10-17 years old; mean: 13.67 +/- 1.08) with gynecomastia were enrolled into the study group. A total of 65 healthy age-matched adolescents were included in the control group. Body mass index (BMI), Tanner staging, testis volume, stretched penis length (SPL) and bone age were evaluated. Serum follicle-stimulating hormone, luteinizing hormone (LH), estradiol (E2), testosterone, free testosterone, SHBG, PSA levels were determined and FAI was calculated. In the study group, free testosterone (p = 0.012) and FAI (p = 0.05) were significantly lower than the control group. In the control group, SHBG levels decreased (p 0.05). High FAI was found to decrease the risk of gynecomastia (odds ratio: 0.211, 95% confidence interval: 0.064-0.694, p = 0.01). PSA showed a positive correlation with FAI, free testosterone, Tanner staging, testosterone, E2 and LH levels. PSA is a good indicator of androgen activity during puberty. However, owing to FAI remaining as the single significant variable for pubertal gynecomastia, we suggest that it is still the best parameter to elucidate the etiopathogenesis of gynecomastia as well as other pubertal developmental abnormalities in male adolescents, and further longitudinal studies are needed to investigate the relationships between PSA and FAI in puberty.

Pubertal development and prostate cancer risk

DEFF Research Database (Denmark)

Bonilla, Carolina; Lewis, Sarah J; Martin, Richard M

2016-01-01

, 0.91-1.00) and prostate cancer-specific mortality (hazard ratio amongst cases, per tertile: 0.94; 95 % CI, 0.90-0.98), but not with disease grade. CONCLUSIONS: Older age at sexual maturation is causally linked to a reduced risk of later prostate cancer, especially aggressive disease.......BACKGROUND: Epidemiological studies have observed a positive association between an earlier age at sexual development and prostate cancer, but markers of sexual maturation in boys are imprecise and observational estimates are likely to suffer from a degree of uncontrolled confounding. To obtain...... to a difference of one Tanner stage between pubertal boys of the same age) was associated with a 77 % (95 % CI, 43-91 %) reduced odds of high Gleason prostate cancer. In PRACTICAL, the puberty genetic score was associated with prostate cancer stage (OR of advanced vs. localized cancer, per tertile: 0.95; 95 % CI...

Facing changes and changing faces in adolescence: a new model for investigating adolescent-specific interactions between pubertal, brain and behavioral development.

Science.gov (United States)

Scherf, K Suzanne; Behrmann, Marlene; Dahl, Ronald E

2012-04-01

Adolescence is a time of dramatic physical, cognitive, emotional, and social changes as well as a time for the development of many social-emotional problems. These characteristics raise compelling questions about accompanying neural changes that are unique to this period of development. Here, we propose that studying adolescent-specific changes in face processing and its underlying neural circuitry provides an ideal model for addressing these questions. We also use this model to formulate new hypotheses. Specifically, pubertal hormones are likely to increase motivation to master new peer-oriented developmental tasks, which will in turn, instigate the emergence of new social/affective components of face processing. We also predict that pubertal hormones have a fundamental impact on the re-organization of neural circuitry supporting face processing and propose, in particular, that, the functional connectivity, or temporal synchrony, between regions of the face-processing network will change with the emergence of these new components of face processing in adolescence. Finally, we show how this approach will help reveal why adolescence may be a period of vulnerability in brain development and suggest how it could lead to prevention and intervention strategies that facilitate more adaptive functional interactions between regions within the broader social information processing network. Copyright © 2011 Elsevier Ltd. All rights reserved.

Facing changes and changing faces in adolescence: A new model for investigating adolescent-specific interactions between pubertal, brain and behavioral development

Science.gov (United States)

Scherf, K. Suzanne; Behrmann, Marlene; Dahl, Ronald E.

2015-01-01

Adolescence is a time of dramatic physical, cognitive, emotional, and social changes as well as a time for the development of many social-emotional problems. These characteristics raise compelling questions about accompanying neural changes that are unique to this period of development. Here, we propose that studying adolescent-specific changes in face processing and its underlying neural circuitry provides an ideal model for addressing these questions. We also use this model to formulate new hypotheses. Specifically, pubertal hormones are likely to increase motivation to master new peer-oriented developmental tasks, which will in turn, instigate the emergence of new social/affective components of face processing. We also predict that pubertal hormones have a fundamental impact on the reorganization of neural circuitry supporting face processing and propose, in particular, that, the functional connectivity, or temporal synchrony, between regions of the face-processing network will change with the emergence of these new components of face processing in adolescence. Finally, we show how this approach will help reveal why adolescence may be a period of vulnerability in brain development and suggest how it could lead to prevention and intervention strategies that facilitate more adaptive functional interactions between regions within the broader social information processing network. PMID:22483070

Veterinary attitudes towards pre-pubertal gonadectomy of cats: a comparison of samples from New Zealand, Australia and the United Kingdom.

Science.gov (United States)

Farnworth, M J; Adams, N J; Seksel, K; Waran, N K; Beausoleil, N J; Stafford, K J

2013-07-01

To compare the attitudes and practices of a sample of veterinarians in New Zealand, Australia and the United Kingdom (UK) towards pre-pubertal gonadectomy of cats. Respondents' demographics were gathered using an electronic questionnaire distributed via professional veterinary associations in the target countries, as were minimum age at gonadectomy and typical age of puberty. Desirability of prepubertal gonadectomy was gauged using three response categories ('yes', 'no' or 'sometimes'), respondents were then able to justify the response given. Two-way Analyses of Variance (ANOVA) followed by post hoc Tukey HSD tests were used to test whether there were differences in minimum ages for gonadectomy within and between countries and between providers and non-providers of services to pounds (or animal welfare centres). Views on the desirability of prepubertal gonadectomy relative to demographics were explored using a Likelihood Ratio Test. The survey received 717 responses. Most respondents believed pre-pubertal gonadectomy was either entirely or 'sometimes' desirable (556/621), few thought it was undesirable (65/621). Minimum age at gonadectomy was significantly affected by country surveyed and provision or non-provision of services for pounds. Post hoc Tukey HSD analysis indicated the mean age of both spaying and castration (4.3 months) in the UK was significantly different from both Australia (spaying: 3.4 months, castration: 3.2 months) and New Zealand (spaying: 3.4 months, castration: 3.2 months) (all ppre- pubertal gonadectomy. Respondents from the UK were more likely to answer 'no' (p = 0.004) or 'sometimes' (p = 0.050) as compared to those from New Zealand or Australia. Females were more likely to respond with 'sometimes' as opposed to 'yes' than males. Reasons for considering pre-pubertal gonadectomy desirable or sometimes desirable focussed on reducing unwanted pregnancies and improving population control, as well as improving rates of adoption, owner

The Relationship among Pubertal Stage, Age, and Drinking in Adolescent Boys and Girls

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Faden, Vivian B.; Ruffin, Beverly; Newes-Adeyi, Gabriella; Chen, Chiung

2010-01-01

This study used data from the Third National Household and Nutrition Examination Survey (NHANES) to examine the association between pubertal status (Tanner staging for boys and girls and menarche for girls) and alcohol use in a nationally representative sample of youths ages 12 to 17. Logistic regression was used to model the relationship. In…

Impact of socio-emotional context, brain development, and pubertal maturation on adolescent risk-taking.

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Smith, Ashley R; Chein, Jason; Steinberg, Laurence

2013-07-01

While there is little doubt that risk-taking is generally more prevalent during adolescence than before or after, the underlying causes of this pattern of age differences have long been investigated and debated. One longstanding popular notion is the belief that risky and reckless behavior in adolescence is tied to the hormonal changes of puberty. However, the interactions between pubertal maturation and adolescent decision making remain largely understudied. In the current review, we discuss changes in decision making during adolescence, focusing on the asynchronous development of the affective, reward-focused processing system and the deliberative, reasoned processing system. As discussed, differential maturation in the structure and function of brain systems associated with these systems leaves adolescents particularly vulnerable to socio-emotional influences and risk-taking behaviors. We argue that this asynchrony may be partially linked to pubertal influences on development and specifically on the maturation of the affective, reward-focused processing system. Copyright © 2013 Elsevier Inc. All rights reserved.

Pubertal development and fertility in survivors of childhood acute myeloid leukemia treated with chemotherapy only

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Molgaard-Hansen, Lene; Skou, Anne-Sofie; Juul, Anders

2013-01-01

More than 60% of children with acute myeloid leukemia (AML) become long-term survivors. Most are cured using chemotherapy without hematopoietic stem cell transplantation (HSCT). We report on pubertal development and compare self-reported parenthood among AML survivors and their siblings....

Effect of A 16 Week Combined Strength and Plyometric Training Program Followed by A Detraining Period on Athletic Performance in Pubertal Volleyball Players.

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Fathi, Abed; Hammami, Raouf; Moran, Jason; Borji, Rihab; Sahli, Sonia; Rebai, Haithem

2018-02-01

The purpose of this study was to determine the effects of 16 weeks of combined strength and plyometric training or plyometric training alone, and how a detraining program can modify adaptations in response to the training stimulus. Sixty male volleyball players (circa PHV:-1 to +1 years from PHV) were assigned to a Combined Training group (CTG) (n=20), a Plyometric Training group (PTG) (n=20) or a control group (CG) (n=20). The experimental groups (CTG and PTG) participated in training twice weekly for 16 weeks. Thigh muscle volume, body fat, flexibility, sprint, jump height and medicine ball throw were measured at pre-training, post-training and detraining. Respectively, the CTG and PTG showed increases in thigh muscle volume (Effect size: 0.71 and 0.42), and decreases in body fat (-0.42 and -0.34) as well as improvements in 5 m sprint (-0.69 and -0.46) 10 m sprint (-0.31 and -0.3), lower body muscle power (0.44 and 0.36) and upper body muscle power (1.32 and 0.7). After the detraining period, all groups maintained previously attained muscle power (6.79% to 9.87%; pplyometric training provided better improvements than plyometric training only. The combination of strength and plyometric training is a time-effective training modality that confers improvements in physical performance measures, muscle size and body fat. A temporary period of detraining may not undermine performance gains in pubertal volleyball players.

Maternal swimming exercise during pregnancy attenuates anxiety/depressive-like behaviors and voluntary morphine consumption in the pubertal male and female rat offspring born from morphine dependent mothers.

Science.gov (United States)

Torabi, Masoumeh; Pooriamehr, Alireza; Bigdeli, Imanollah; Miladi-Gorji, Hossein

2017-10-17

This study was designed to examine whether maternal swimming exercise during pregnancy would attenuate prenatally morphine-induced anxiety, depression and voluntary consumption of morphine in the pubertal male and female rat offspring. Pregnant rats during the development of morphine dependence were allowed to swim (30-45min/d, 3days per a week) on gestational days 11-18. Then, the pubertal male and female rat offspring were tested for the elevated plus-maze (EPM), sucrose preference test (SPT) and voluntary morphine consumption using a two-bottle choice (TBC) paradigm. The results showed that male and female rat offspring born of the swimmer morphine-dependent mothers exhibited an increase in EPM open arm time and entries, higher levels of sucrose preference than their sedentary control mothers. Voluntary consumption of morphine was less in the male and female rat offspring born of the swimmer morphine-dependent mothers as compared with their sedentary control mothers during three periods of the intake of drug. Thus, swimming exercise in pregnant morphine dependent mothers decreased anxiety, depressive-like behavior and also the voluntary morphine consumption in the pubertal male and female offspring, which may prevent prenatally morphine-induced behavioral sensitization in offspring. Copyright © 2017 Elsevier B.V. All rights reserved.

BMI percentile-for-age overestimates adiposity in early compared with late maturing pubertal children

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Sørensen, Kaspar; Juul, Anders

2015-01-01

and bioelectric impedance analyses (BIA) were used to estimate adiposity. Clinical pubertal markers (Tanner stages and testicular volume) were evaluated. LH, FSH, estradiol, testosterone, SHBG and IGF1 levels were determined by immunoassays. RESULTS: In all age groups, higher BMI (all 1 year age-groups, P ≤ 0...

Relationships between anthropometric features, body composition, and anaerobic alactic power in elite post-pubertal and mature male taekwondo athletes

Directory of Open Access Journals (Sweden)

Boraczyński Michał

2017-12-01

Full Text Available Purpose. The paper describes the relationships between anthropometric features, body composition, and anaerobic alactic power (AAP in elite post-pubertal and mature male taekwondo athletes. Methods. The sample of 41 taekwondo athletes was divided into two groups: post-pubertal (P-P, n = 19, Mage = 15.6 ± 1.1 years and mature (M, n = 22, Mage = 20.7 ± 2.8 years. Anthropometric features (WB-150, ZPU Tryb-Wag, Poland, body composition (BC-418 MA, Tanita, Japan, maturational status (Pubertal Maturational Observational Scale, and AAP (10-s version of the Wingate Anaerobic Test were assessed. Results. Post-hoc testing revealed significant between-group differences (3.2-20.4%, p < 0.01 in all anthropometric and body composition measures, with effect sizes (ES between −0.79 and −1.25 (p < 0.001, except for fat content and percentage of skeletal muscle mass (SMM (p ≥ 0.05. In group M, the maximal power output (Pmax was greater (ES = −1.15, p < 0.001 and the time of its attainment shorter (ES = 0.59, p < 0.001 than in group P-P. Correlation analyses indicated notably strong associations between body mass (BM and Pmax in group P-P (r = 0.950 [95% CI, 0.85-0.98], p < 0.001 and M (r = 0.926 [95% CI, 0.81-0.97], p < 0.001, and similar-sized strong correlations between fat-free mass (FFM and Pmax in group P-P (r = 0.955 [95% CI, 0.86-0.99], p < 0.001 and M (r = 0.924 [95% CI, 0.82-0.96], p < 0.001. Additionally, a strong correlation was found between body height and Pmax in groups P-P and M (r = 0.805 [95% CI, 0.54-0.92], p < 0.001 and r = 0.819 [95% CI, 0.58-0.93], p < 0.001, respectively. Linear regression analyses demonstrated that FFM, BM, and absolute SMM best explained the variance in Pmax in both groups (r, 0.939-0.951; r2, 0.882-0.909. Conclusions. The strong correlations observed in both groups between BM, FFM, SMM, and Pmax demonstrate the significant effects of body size and composition on AAP. By determining the current levels of these

Perception regarding pubertal changes among rural adolescent boys of Haryana: A school based study

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Vinod Chayal

2016-06-01

Full Text Available Background: Adolescence is a transition phase through which a child matures into an adult. The physical changes in the human body are from infant to child to adolescence to adult to old age.  All phases of life behave like a coin with both good and bad facets attached to each phase of life. Aims & Objectives:  1. To study perception and awareness regarding pubertal changes among school going adolescent boys. 2. To study the association between education and perceived pubertal problems among study subjects. Material & Methods: The study was conducted among male students of senior secondary schools of community development block Beri in one year. The study universe comprised of students in middle and late adolescence (aged 14-18 years studying in 9th to 12th classes of the senior secondary schools in the area. A total of 1000 male students were selected from these schools which were more than the required sample size of 891. Results: The study found that 42.66% students and a half (50% of students of class 9th & 10th and class 11th & 12th respectively considered that pubertal changes as a normal phenomenon. The majority of students admitted practicing masturbation and felt shy and guilty for practicing masturbation, also students felt fatigued after night emission. Conclusions: The study concludes that adolescent’s sexuality which often causes controversy and concern among adults is least discussed with them during adolescence. The reasons for this may be many, including moral grounds or because of concomitant health risks and threats to wellbeing.

Hormonal, anthropometric and lipid factors associated with idiopathic pubertal gynecomastia.

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Al Alwan, Ibrahim; Al Azkawi, Hanan; Badri, Motasim; Tamim, Hani; Al Dubayee, Mohammed; Tamimi, Waleed

2013-01-01

To determine factors associated with pubertal gynecomastia. A cross-sectional study among healthy male school children and adolescents in Riyadh, Saudi Arabia. Subjects were selected from diverse socioeconomic backgrounds. Tanner stage, height, weight, blood hormonal levels (leutilizing hormone [LH], follicle-stimulating hormone [FSH], total testosterone, and estradiol), and anthropometric and lipid parameters (body mass index [BMI], triglycerides, high-density lipoprotein [HDL], and low-density lipoprotein [LDL]), were collected and compared in children with and without gynecomastia. The study included 542 children and adolescents. Median (interquartile range) age in the whole group was 11(8-13) years. The prevalence of gynecomastia was 185/542 (34%), with a peak at age 14. The 2 groups compared had nonsignificant difference in cholesterol (P=.331), LH (P=.215) and FSH (P=.571) levels. Those with gynecomastia were significantly older, had lower gonad stage, had higher anthropometric (height, weight, and BMI), and lipid (triglycerides, HDL, and LDL) values. In multivariate regression analysis, factors significantly associated with gynecomastia were BMI (odds ratio [OR]=1.05; 95%CI 1.00-1.10; P=.013), HDL (OR=0.42; 95%CI 0.19-0.92; P=.03), and gonad (Stage II OR=2.23; 95%CI 1.27-3.92; P=.005, Stage III OR=6.40; 95%CI 2.70-15.0; P gynecomastia tends to increase in mid-puberty. In our setting, BMI, HDL, and gonad stage were the major factors associated with the development of pubertal gynecomastia.

The association of pain and depression in preadolescent girls: moderation by race and pubertal stage.

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Keenan, Kate; Hipwell, Alison E; Hinze, Amanda E; Babinski, Dara E

2009-08-01

To test whether an association between pain response and depression in females is present during preadolescence using a controlled pain stimulus and a clinically relevant assessment of depressive symptoms. In a sample of 232 girls, pain threshold and tolerance were assessed at age 10 years using the cold pressor task, and a diagnostic interview was used to assess depression symptoms at 10 and 11 years of age. Response to pain at age 10 was associated with depressive symptoms at ages 10 and 11; race and pubertal stage moderated the association. Pain response and depression were more strongly associated among girls who had reached advanced stages of pubertal development and among European American girls. The results add to the existing literature on the co-occurrence of depression and pain by demonstrating modest but consistent concurrent and prospective associations between response to pain and depression among girls during preadolescence.

Mutational Analysis of TAC3 and TACR3 Genes in Patients with Idiopathic Central Pubertal Disorders

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Tusset, Cintia; Noel, Sekoni D.; Trarbach, Ericka B.; Silveira, Letícia F. G.; Jorge, Alexander A. L.; Brito, Vinicius N.; Cukier, Priscila; Seminara, Stephanie B.; de Mendonça, Berenice B.; Kaiser, Ursula B.; Latronico, Ana Claudia

2013-01-01

Aim To investigate the presence of variants in the TAC3 and TACR3 genes, which encode NKB and its receptor (NK3R), respectively, in a large cohort of patients with idiopathic central pubertal disorders. Patients and Methods Two hundred and thirty seven patients were studied: 114 with central precocious puberty (CPP), 73 with normosmic isolated hypogonadotropic hypogonadism (IHH) and 50 with constitutional delay of growth and puberty (CDGP). The control group consisted of 150 Brazilian individuals with normal pubertal development. Genomic DNA was extracted from peripheral blood and the entire coding region of both TAC3 and TACR3 genes were amplified and automatically sequenced. Results We identified one variant (p.A63P) in NKB and four variants, p.G18D, p.L58L (c.172C>T), p.W275* and p.A449S in NK3R, which were absent in the control group. The p.A63P variant was identified in a girl with CPP, and p.A449S in a girl with CDGP. The known p.G18D, p.L58L and p.W275* variants were identified in three unrelated males with normosmic IHH. Conclusion Rare variants in the TAC3 and TACR3 genes were identified in patients with central pubertal disorders. Loss-of-function variants of TACR3 were associated with the normosmic IHH phenotype. PMID:23329188

Adult Height after Growth Hormone Treatment at Pubertal Onset in Short Adolescents Born Small for Gestational Age: Results from a Belgian Registry-Based Study

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M. Thomas

2018-01-01

Full Text Available Objectives. Information on the efficacy of GH treatment in short SGA children starting their treatment in adolescence is limited. Therefore, adult height (AH, total height gain, and pubertal height gain were evaluated in short SGA children who started GH treatment at pubertal onset. Patient and Methods. Growth data of 47 short SGA adolescents (22 boys who started GH treatment at pubertal onset (PUB group were compared with results from 27 short SGA patients (11 boys who started GH therapy at least 1 year before pubertal onset (PrePUB group. Results. The PUB group achieved a mean (±SD total height gain of 0.8 ± 0.7 SDS and an AH of −2.5 ± 0.7 SDS after 4.1 ± 1.1 years of GH treatment with a dosage of 41.8 ± 8.4 μg/kg/day. These results were comparable with those in the PrePUB group, which was treated for a longer duration (5.8 ± 2.1 years, resulting in a total height gain of 1.1 ± 0.7 SDS and an AH of −2.1 ± 1.0 SDS. Multiple regression analysis showed a significantly lower height gain in pubertal patients, females, and patients weighing less at start of GH treatment. An AH above −2 SDS and above the parent-specific lower limit of height was, respectively, reached in 28% and 70% of PUB and 44% and 67% of PrePUB patients (NS. AH SDS was positively correlated with the height SDS at start of GH. Conclusions. Short SGA adolescents starting GH therapy at an early pubertal stage have a modest and variable height gain. A normal AH can be expected in one third of the patients, especially in those with a smaller height deficit at onset of GH treatment.

Serum levels of INSL3, AMH, Inhibin B and Testosterone during pubertal transition in healthy boys

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Lindhardt Johansen, Marie; Anand-Ivell, Ravinder; Mouritsen, Annette

2014-01-01

to luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, inhibin B, and anti-Müllerian hormone (AMH) during puberty in healthy boys.MethodsTen boys were included from the longitudinal part of the COPENHAGEN Puberty Study. Pubertal evaluation, including testicular volume, was performed...... and blood samples drawn every 6 months for 5 years. Serum concentrations of testosterone were determined by a newly developed LC-MS/MS method, and serum concentrations of INSL3, AMH, inhibin B, FSH and LH, respectively, were determined by validated immunoassays.ResultsSerum INSL3 levels increased...... progressively with increasing age, pubertal onset and testicular volume. In six of ten boys, LH increased prior to the first observed increase in INSL3. In the remaining four boys, the increase in LH and INSL3 was observed at the same examination. The increases in serum concentrations of LH, testosterone...

Sex steroids and brain structure in pubertal boys and girls: a mini-review of neuroimaging studies

NARCIS (Netherlands)

Peper, J.S.; Hulshoff Pol, H.E.; Crone, E.A.; van Honk, J.

2011-01-01

Puberty is an important period during development hallmarked by increases in sex steroid levels. Human neuroimaging studies have consistently reported that in typically developing pubertal children, cortical and subcortical gray matter is decreasing, whereas white matter increases well into

Effects of rumen-undegradable protein on intake, performance, and mammary gland development in prepubertal and pubertal dairy heifers.

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Silva, A L; Detmann, E; Dijkstra, J; Pedroso, A M; Silva, L H P; Machado, A F; Sousa, F C; Dos Santos, G B; Marcondes, M I

2018-04-04

The objective of this study was to evaluate the influence of different amounts of rumen-undegradable protein (RUP) on intake, N balance, performance, mammary gland development, carcass traits, and hormonal status of Holstein heifers at different physiological stages (PS). Sixteen prepubertal (PRE) heifers (initial BW = 106 ± 7.6 kg; age = 4.3 ± 0.46 mo) and 16 pubertal (PUB) heifers (initial BW = 224 ± 7.9 kg; age = 12.6 ± 0.45 mo) were used in an experiment over a period of 84 d. Four diets with increasing RUP contents (38, 44, 51, and 57% of dietary crude protein) and heifers at 2 PS (PRE or PUB) were used in a 4 × 2 factorial arrangement of treatments in a completely randomized design. Throughout the experiment, 2 digestibility trials were performed over 5 consecutive days (starting at d 36 and 78) involving feed and ort sampling and spot collections of feces and urine. At d 0 and 83, body ultrasound images were obtained for real-time carcass trait evaluation. The mammary gland was ultrasonically scanned at d 0 and every 3 wk during the experiment. Blood samples were taken at d 0 and 84 to determine serum concentrations of progesterone, estrogen, insulin-like growth factor I (IGF-I), and insulin. No interaction between PS and the level of RUP was found for any trait. Apparent digestibility of dry matter, organic matter, and neutral detergent fiber corrected for ash and protein was not affected by RUP level but was lower for PRE compared with PUB heifers. Sorting against neutral detergent fiber corrected for ash and protein (tendency only) and for crude protein was greater for PUB than PRE heifers. Pubertal heifers had greater average daily gain (905 vs. 505 g/d) and N retention (25.9 vs. 12.5 g/d) than PRE heifers. In addition, average daily gain and N retention were greatest at 51% RUP of dietary protein. Mammary ultrasonography indicated no effects of RUP amounts on mammary gland composition, whereas PRE heifers had greater pixel values than PUB

Diagnostic Markers of Primary Infertility in Women of Reproductive Age with Hypothalamic Dysfunction in the Pubertal Period

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Irina V. Zhukovets

2017-09-01

Full Text Available The aim of the study was to assess fertility in women of reproductive age with hypothalamic dysfunction (HD in the pubertal period and to determine the diagnostic significance of pro-inflammatory (TNF-α and IL-1β, anti-inflammatory cytokine (IL-10 and NF-kB activity in the diagnosis of primary infertility in these women. Materials and Methods: Fertility was assessed in 86 women of reproductive age with HD in the pubertal period. A comparative characteristic of fertile women (Group 1, n=46 and primary infertility women (Group 2, n=21 with HD in the pubertal period was performed. FPG and FPI were determined after 8 to 12 hours of fasting. Serum IRI concentrations were measured using an ELISA kit. The levels of TNF-α, IL-1β and IL-10 were determined in the venous blood serum after a 12-hour fasting, as well as in UA on the 21st day of the menstrual cycle using ELISA kits. The activity of NF-kB was determined in UA on the 21st day of the menstrual cycle using an enzyme immunoassay kit. Results: BMI in Group 1 was significantly lower than in Group 2: 22.63±2.68 kg/m2 versus 27.05±4.03kg/m2 (p=0.000. WC in women of Group 1 was 66.11±5.66cm versus 78.52±10.54cm in Group 2 (p = 0.000; WC >80cm was found in 2(4.4% and 14(66.7% women, respectively (p = 0.000. The average levels of FPG and FPI were significantly higher in Group 2. Serum levels of TNF-α and IL-1β in Group 2 were significantly higher than in Group 1. The serum level of anti-inflammatory cytokine IL-10 was significantly lower in Group 2; accordingly, the TNF-α/IL-10 ratio in Group 2 was 1.8 times higher than in Group 1. The IL-1β level in UA (P=0.000 and the TNF-α/IL-10 ratio (P=0.02 were significantly higher in women of Group 2 than Group 1, which indicated the pronounced inflammatory effects of TNF-α in the endometrium. Imbalance in the production of pro-inflammatory and anti-inflammatory factors indicated the activation of the Th-1 immune response with the formation of the

Anxiety Symptoms in African American Youth: The Role of Puberty and Biological Sex

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Carter, Rona

2015-01-01

This study examined the effects of pubertal status, pubertal timing (actual and perceived), and youth biological sex on symptom dimensions of anxiety (i.e., social, separation, harm avoidance, physical) in African Americans (n = 252; ages 8-12). For girls, results indicated that pubertal status and timing (actual) exerted similar effects for some…

The Effects of Pubertal Timing on Body Image, School Behavior, and Deviance.

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Duncan, Paula Duke; And Others

1985-01-01

Data from the National Health Examination Survey, a national probability sample of children and youth aged 12-17, was used to investigate the relationships between maturational timing and body image, school behavior, and deviance. (Author/LMO)

Puberty: Maturation, Timing and Adjustment, and Sexual Identity Developmental Milestones among Lesbian, Gay, and Bisexual Youth

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Grossman, Arnold H.; Foss, Alexander H.; D'Augelli, Anthony R.

2014-01-01

This study examined pubertal maturation, pubertal timing and outcomes, and the relationship of puberty and sexual identity developmental milestones among 507 lesbian, gay, and bisexual youth. The onset of menarche and spermarche occurred at the mean ages of 12.05 and 12.46, respectively. There was no statistically significant difference in…

Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio).

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Sharma, Prakash; Patiño, Reynaldo

2013-04-01

We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent. Published by Elsevier Inc.

Regulation of gonadal sex ratios and pubertal development by the thyroid endocrine system in zebrafish (Danio rerio)

Science.gov (United States)

Sharma, Prakash; Patino, Reynaldo

2013-01-01

We examined associations between thyroid condition, gonadal sex and pubertal development in zebrafish. Seventy-two-hour postfertilization larvae were reared in untreated medium or in the presence of goitrogens (sodium perchlorate, 0.82 mM; methimazole, 0.15 and 0.3 mM) or thyroxine (1 and 10 nM) for 30 days. Thyrocyte height, gonadal sex and gonadal development were histologically determined at 45 and 60 days postfertilization (dpf). Thyrocyte hypertrophy, an index of hypothyroidism, was observed at 45 and 60 dpf in perchlorate-treated but only at 45 dpf in methimazole-treated fish. Similarly, gonadal sex ratios were biased toward ovaries relative to control animals at 45 and 60 dpf in perchlorate-treated fish but only at 45 dpf in methimazole-treated fish. Gonadal sex ratios were biased toward testes at 45 and 60 dpf in thyroxine-treated fish. Spermatogenesis was delayed in testes from goitrogen-treated fish at 60 dpf relative to control values, but was unaffected in testes from thyroxine-treated individuals. Oogenesis seemed to be nonspecifically delayed in all treatments relative to control at 60 dpf. This study confirmed the previously reported association between hypothyroid condition and ovarian-skewed ratios, and hyperthyroid condition and testicular-skewed ratios, and also showed that male pubertal development is specifically delayed by experimental hypothyroidism. The simultaneous recovery from the hypothyroid and ovary-inducing effects of methimazole by 60 dpf (27 days post-treatment) suggests that the ovary-skewing effect of goitrogens is reversible when thyroid conditions return to basal levels before developmental commitment of gonadal sex. Conversely, the masculinizing effect of hyperthyroidism seems to be stable and perhaps permanent.

Pubertal Stress and Nutrition and their Association with Sexual Orientation and Height in the Add Health Data.

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Skorska, Malvina N; Bogaert, Anthony F

2017-01-01

A number of studies have indicated that gay men tend to be shorter, on average, than heterosexual men. Less evidence exists that lesbian women are taller, on average, than heterosexual women. The most popular explanation of the association between sexual orientation and height involves prenatal factors, such that, for example, gay men may have been exposed to lower than typical androgens during fetal development, which impacts their height and sexual orientation as adults. An alternative explanation involves stress, given that stress has been associated with sexual minority identification and with lower height. Another alternative explanation involves nutrition, although its relationship is less clear with sexual minority identification. Using the Add Health data, which is a large, nationally representative and longitudinal sample of American adolescents (n = 14,786), we tested a mediation model, such that sexual orientation → pubertal stress/nutrition → height. Within men, we found that gay men (n = 126) were shorter, on average, than heterosexual men (n = 6412). None of the 24 pubertal stress-related and 15 pubertal nutrition-related variables assessed in the Add Health data mediated the relationship between sexual orientation and height in men. Within women, lesbians (n = 75) did not differ significantly in stature compared to heterosexual women (n = 6267). Thus, prenatal mechanisms (e.g., hormones, maternal immune response) are likely better candidates for explaining the height difference between gay men and heterosexual men.

Pubertal development in children diagnosed with diabetes mellitus type 1 before puberty.

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Pereira, K C X; Pugliese, B S; Guimarães, M M; Gama, M P

2015-02-01

To investigate an association between pubertal development and timing of menarche with glycemic control, disease duration, and body mass index (BMI) in patients diagnosed with diabetes mellitus type 1 (DM1) before puberty. Retrospective study. The study was performed at the diabetes outpatient clinic of Instituto de Puericultura e Pediatria Martagão Gesteira--IPPMG of the Federal University of Rio de Janeiro--UFRJ. A total of 131 children, 61 girls and 70 boys, diagnosed with DM1 before puberty participated in the study. The study investigated how age at puberty onset relates to mean glycated hemoglobin (HbA1c) before puberty, BMI percentile, and disease duration; how puberty duration relates to mean HbA1c before and during puberty and to disease duration; and how timing of menarche relates to mean HbA1c before puberty, BMI percentile, and disease duration. Age at puberty onset was positively correlated with mean HbA1c before puberty (r = 0.204, R(2) = 0.042; P = .019) and disease duration (r = 0.451, R(2) = 0.203; P puberty later than those diagnosed more recently. Girls in higher BMI percentiles reached menarche sooner.

The Interplay between Gaze Following, Emotion Recognition, and Empathy across Adolescence; a Pubertal Dip in Performance?

NARCIS (Netherlands)

van Rooijen, R.; Junge, C.M.M.; Kemner, C.

2018-01-01

During puberty a dip in face recognition is often observed, possibly caused by heightened levels of gonadal hormones which in turn affects the re-organization of relevant cortical circuitry. In the current study we investigated whether a pubertal dip could be observed in three other abilities

Trends in puberty timing in humans and environmental modifiers

DEFF Research Database (Denmark)

Toppari, Jorma; Juul, Anders

2010-01-01

Secular trends in timing of puberty appear to continue although under-nutrition has not been any longer a limiting factor for pubertal development. Now obesity and other environmental reasons have been suspected to cause this trend, and endocrine disrupting chemicals have become into focus...... as possible contributors. Epidemiological studies on endocrine disrupters are still scarce and show only weak associations between exposures and timing of puberty. Since genetic background explains 50-80% of variability in the timing of puberty, it is not surprising that the observed environmental effects...

An Unexpected Cause of Pelvic Pain in a Pubertal Case: Herlyn-Werner-Wunderlich Syndrome

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Yasemin Kayadibi

2014-03-01

Full Text Available Uterovaginal duplication with imperforated hemivagina is a rare type of Mullerian anomaly. If ipsilateral renal agenesis is associated with this complex genital malformation, it is called Herlyn-Werner-Wunderlich syndrome. Clinical presentations of this syndrome include pelvic pain and mass effect due to obstructed hemivagina in pubertal adolescents and adults. Hematocolpos, even after menstruation period, leads to misdiagnosis. Laparotomy is the gold standard for the diagnosis, however, magnetic resonance imaging has an accuracy upto 100% in evaluating uterovajinal anatomy. In this article, we aimed to present ultrasonographic and magnetic resonance imaging findings in a patient with Herlyn-Werner-Wun derlich syndrome who presented with cyclic pelvic pain. (The Me­di­cal Bul­le­tin of Ha­se­ki 2014; 52: 60-3

The reliability of dental x-ray film in assessment of MP3 stages of the pubertal growth spurt.

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Abdel-Kader, H M

1998-10-01

The main object of this clinical study is to provide a simple and practical method to assess the pubertal growth spurt stages of a subject by recording MP3 stages with the dental periapical radiograph and the standard dental x-ray machine.

Distributed pubertal growth in girls after acute leukemia: a relative growth hormone insufficiency with late presentation

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Moell, C.

1988-01-01

Long-term follow-up of growth and development after acute lymphoblastic leukaemia (ALL) in childhood has previously been limited to the prepubertal period. This study describes pubertal growth, final height and the spontaneous secretion of GH in girls treated for ALL, including CNS irradiation with 24 GY. Ten girls, treated earlier for ALL, experienced the menarche at a mean age of 12.2 years. This is significantly earlier than the mean for Swedish girls. Prepubertal growth was near normal after the end of therapy for leukaemia. Mean final height was -1.7 SD, which is 1.5 SD less than at onset and 1.0 SD less than 1 year after the end of treatment. Thirteen other girls had a blunted spontaneous secretion of GH, several years after treatment for ALL; there was no increase in GH secretion during puberty. These results suggest that girls who have been treated for ALL, including CNS irradiation, have a relative GH insufficiency. This insufficiency becomes obvious only when girls cannot respond to the increased need for GH during the pubertal spurt.

Distributed pubertal growth in girls after acute leukemia: a relative growth hormone insufficiency with late presentation

International Nuclear Information System (INIS)

Moell, C.

1988-01-01

Long-term follow-up of growth and development after acute lymphoblastic leukaemia (ALL) in childhood has previously been limited to the prepubertal period. This study describes pubertal growth, final height and the spontaneous secretion of GH in girls treated for ALL, including CNS irradiation with 24 GY. Ten girls, treated earlier for ALL, experienced the menarche at a mean age of 12.2 years. This is significantly earlier than the mean for Swedish girls. Prepubertal growth was near normal after the end of therapy for leukaemia. Mean final height was -1.7 SD, which is 1.5 SD less than at onset and 1.0 SD less than 1 year after the end of treatment. Thirteen other girls had a blunted spontaneous secretion of GH, several years after treatment for ALL; there was no increase in GH secretion during puberty. These results suggest that girls who have been treated for ALL, including CNS irradiation, have a relative GH insufficiency. This insufficiency becomes obvious only when girls cannot respond to the increased need for GH during the pubertal spurt. (author)

Short-term lower-body plyometric training improves whole body BMC, bone metabolic markers, and physical fitness in early pubertal male basketball players.

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Zribi, Anis; Zouch, Mohamed; Chaari, Hamada; Bouajina, Elyes; Ben Nasr, Hela; Zaouali, Monia; Tabka, Zouhair

2014-02-01

The effects of a 9-week lower-body plyometric training program on bone mass, bone markers and physical fitness was examined in 51 early pubertal male basketball players divided randomly into a plyometric group (PG: 25 participants) and a control group (CG: 26 participants). Areal bone mineral density (aBMD), bone mineral content (BMC), and bone area (BA) in the whole body, L2-L4 vertebrae, and in total hip, serum levels of osteocalcin (Oc) and C-terminal telopeptide fragment of Type I collagen (CTx), jump, sprint and power abilities were assessed at baseline and 9 weeks. Group comparisons were done by independent student's t-test between means and analyses of (ANOVA) and covariance (ANCOVA), adjusting for baseline values. PG experienced a significant increase in Oc (p BMC and BA in any measured site, except in whole body BMC of the PG. A positive correlation was observed between percentage increase (Δ%) of physical fitness and those of (Oc) for the PG. In summary, biweekly sessions of lower body plyometric training program were successful for improving whole body BMC, bone formation marker (Oc) and physical fitness in early pubertal male basketball players.

Vegetable and Fruit Intakes Are Associated with hs-CRP Levels in Pre-Pubertal Girls

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Pilar Navarro

2017-03-01

Full Text Available The influence of diet on inflammation in children remains unclear. We aimed to analyze the influence of diet on high-sensitivity C-reactive protein (hs-CRP levels in a pre-pubertal population free of other influences that may affect hs-CRP levels. We determined hs-CRP levels in 571 six- to eight-year-old children using an hs-CRP ELISA kit. Information on food and nutrient intake was obtained through a food-frequency questionnaire. Overall dietary quality was assessed using the Healthy Eating Index (HEI. We found that girls in the highest tertile of hs-CRP levels had a higher intake of saturated fatty acid, and lower intakes of fiber and vitamin E and a lower HEI score when compared to those in tertiles 1 and 2. We also observed a significant decrease in fruit and vegetable intakes by hs-CRP tertile. Factor analysis showed that a dietary pattern that was loaded most strongly with vegetable, fruit, fiber and vitamin A and E intakes correlated negatively (−0.132, p < 0.05 with hs-CRP. No such association was found in boys. In conclusion, our data show that girls with a poorer quality diet show higher hs-CRP levels already at a pre-pubertal age.

Pubertal Onset in Boys and Girls Is Influenced by Pubertal Timing of Both Parents

DEFF Research Database (Denmark)

Wohlfahrt-Veje, Christine; Mouritsen, Annette; Hagen, Casper P

2016-01-01

children in a longitudinal cohort study. Information on parental timing of puberty (earlier, comparable to, or later compared to peers) and menarche age was retrieved from questionnaires. PARTICIPANTS: A total of 672 girls and 846 boys. MAIN OUTCOME MEASURES: Age at onset of pubic hair (PH2+), breasts (B2...

Bone Density and Timing of Puberty in a Longitudinal Study of Girls.

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Cattran, Ashley M; Kalkwarf, Heidi J; Pinney, Susan M; Huang, Bin; Biro, Frank M

2015-06-01

Primary: To examine the relationship between relative timing of puberty with bone mineral density (BMD) in a group of adolescent girls; Secondary: To determine if family history of breast cancer was associated with bone mineral density. Longitudinal study of girls recruited between 6 and 7 years of age seen every 6 months for 5 years, and subsequently seen annually. BMD of the lumbar spine was measured by dual-energy X-ray absorptiometry (DXA) at mean age of 12.5 years; age- and race-specific Z-scores (BMDz) were calculated. Age of pubertal onset was determined by the first occurrence of breast stage 2, and participants were categorized into race-specific early, on-time and late puberty onset groups. BMDz by timing of pubertal onset, and by family history of breast cancer. DXA scans were performed on 227 study participants, and a second scan was performed on 114 participants 2 years later. Age of onset of puberty was inversely correlated with BMDz, r = -0.31 (P puberty was associated with higher BMD. The high shared variance of BMD and timing of pubertal onset implies an underlying biologic basis. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Secular Trends on Birth Parameters, Growth, and Pubertal Timing in Girls with Turner Syndrome

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Joachim Woelfle

2018-02-01

Full Text Available BackgroundWhether children with chromosomal disorders of growth and puberty are affected by secular trends (STs as observed in the general population remains unanswered, but this question has relevance for expectations of spontaneous development and treatment responses.ObjectivesThe aim of the study was to evaluate STs in birth parameters, growth, and pubertal development in girls with Turner syndrome (TS.Study designRetrospective analysis of KIGS data (Pfizer International Growth Database. We included all TS patients who entered KIGS between 1987 and 2012 and were born from 1975 to 2004, who were prepubertal and growth treatment naïve at first entry (total number: 7,219. Pretreatment height and ages at the start of treatment were compared across 5-year birth year groups, with subgroup analyses stratified by induced or spontaneous puberty start.ResultsWe observed significant STs across the birth year groups for birth weight [+0.18 SD score (SDS, p < 0.001], pretreatment height at mean age 8 years (+0.73 SDS, p < 0.001, height at the start of growth hormone (GH therapy (+0.38 SDS, p < 0.001 and start of puberty (+0.42 SDS, p < 0.001. Spontaneous puberty onset increased from 15 to 30% (p < 0.001. Mean age at the start of GH treatment decreased from 10.8 to 7.4 years (−3.4 years; p < 0.001, and substantial declines were seen in ages at onset of spontaneous and induced puberty (−2.0 years; p < 0.001 and menarche (−2.1 years; p < 0.001.ConclusionEnvironmental changes leading to increased height and earlier and also more common, spontaneous puberty are applicable in TS as in normal girls. In addition, greater awareness for TS may underlie trends to earlier start of GH therapy and induction of puberty at a more physiological age.

Interactive effects of ethanol on ulcerative colitis and its associated testicular dysfunction in pubertal BALB/c mice.

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Adedara, Isaac A; Ajayi, Babajide O; Awogbindin, Ifeoluwa O; Farombi, Ebenezer O

2017-11-01

Available epidemiological reports have indicated an increase in the incidence of ulcerative colitis, as well as alcohol consumption, globally. The present study investigated the possible interactive effects of ethanol consumption on ulcerative colitis and its associated testicular dysfunction using six groups of 12 pubertal mice each. Group I (Control) mice received drinking water alone. Group II mice received ethanol alone at 5 g/kg body weight. Group III mice received 2.5% dextran sulphate sodium (DSS) in drinking water followed by normal drinking water. Groups IV, V, and VI mice received DSS followed by ethanol at 1.25, 2.5, and 5 g/kg, respectively. Administration of ethanol to mice with ulcerative colitis intensified the disease-activity index with marked reduction in colon length, colon mass index, body weight gain, and organo-somatic indices of testes and epididymis when compared with the DSS-alone group. Moreover, ethanol exacerbated colitis-mediated decrease in enzymatic and non-enzymatic antioxidants but increased the oxidative stress and inflammatory biomarkers in the testes and epididymis. The diminution in luteinizing hormone, follicle stimulating hormone, and testosterone levels was intensified following administration of ethanol to mice with ulcerative colitis that were administered 5 g/kg ethanol alone. The decrease in sperm functional parameters and testicular spermatogenic indices as well as histopathological damage in colon, testes, and epididymis was aggravated following administration of ethanol to mice with ulcerative colitis. In conclusion, the exacerbating effects of ethanol on ulcerative colitis-induced testicular dysfunction are related to increased oxidative stress and inflammation in the treated mice. Copyright © 2017 Elsevier Inc. All rights reserved.

Relationships of Pubertal Development among Early Adolescents to Sexual and Nonsexual Risk Behaviors and Caregivers' Parenting Behaviors

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Koo, Helen P.; Rose, Allison; Bhaskar, Brinda; Walker, Leslie R.

2012-01-01

Using a school-based sample of fifth graders (mean age = 10.38, SD = 0.66) and their parents (N = 408) from Washington, D.C., the authors examine associations of pubertal development with early adolescents' sexual and nonsexual risk behaviors and their caregivers' parenting behaviors and of these risk behaviors with parenting behaviors. Results…

Androgenetic Alopecia: A Chronic or Pubertal Onset Disease Retarded by Blood Donation

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Mohammad Reza Dayer

2017-09-01

Full Text Available Background Androgenetic alopecia is the main cause of hair loss and common baldness that affects psychological more than physiological aspects of people’s lives. Studies have shown that this multi factorial disorder is initiated by androgens secretion in pubertal period, minerals limitations, autoimmunity, mental stress, genetic predisposition and some alterations in hematological factors. Objectives The aim of this study was to evaluate the involvement of hematologic parameters in this disease using a case control study design. Methods In this case-controlled study, two groups each of 80 individuals with androgenetic alopecia were voluntarily included in the study based on their medical histories and clinical examinations and subjected to blood tests for routine hematological parameters. The results were then compared and analyzed using SPSS version 16.0. Results Our findings indicated that all the parameters for both groups fall in normal ranges (Mean ± SD but the values for RBC, HGB, MCH, MCHC, WBC, LYM and TIBC were significantly higher in patients than in normal group. The average counts of PLT was significantly lower in patients compared with the normal group. Otherwise, Person’s tests for statistical correlations between two groups indicated that the pattern of correlations were abnormal in patients. Conclusions Our findings indicated the presence of a chronic, immunologic and slowly progressing disorder that causes hair loss, the disease which is in turn triggered in pubertal period upon androgen secretion. We suggest, therefore, that the conditions may be ameliorated by prescription of iron tablet, platelet transfusion and anti-inflammation therapy.

The Effect of Low Monotonic Doses of Zearalenone on Selected Reproductive Tissues in Pre-Pubertal Female Dogs—A Review

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Magdalena Gajęcka

2015-11-01

Full Text Available The growing interest in toxic substances combined with advancements in biological sciences has shed a new light on the problem of mycotoxins contaminating feeds and foods. An interdisciplinary approach was developed by identifying dose-response relationships in key research concepts, including the low dose theory of estrogen-like compounds, hormesis, NOAEL dose, compensatory response and/or food tolerance, and effects of exposure to undesirable substances. The above considerations increased the researchers’ interest in risk evaluation, namely: (i clinical symptoms associated with long-term, daily exposure to low doses of a toxic compound; and (ii dysfunctions at cellular or tissue level that do not produce clinical symptoms. Research advancements facilitate the extrapolation of results and promote the use of novel tools for evaluating the risk of exposure, for example exposure to zearalenone in pre-pubertal female dogs. The arguments presented in this paper suggest that low doses of zearalenone in commercial feeds stimulate metabolic processes and increase weight gains. Those processes are accompanied by lower proliferation rates in the ovaries, neoangiogenesis and vasodilation in the ovaries and the uterus, changes in the steroid hormone profile, and changes in the activity of hydroxysteroid dehydrogenases. All of the above changes result from exogenous hyperestrogenizm.

Assessment of insulin like growth factor-1 and IGF binding protein-3 in healthy Indian girls from Delhi and their correlation with age, pubertal status, obesity and thyroid hormonal status.

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Marwaha, Raman K; Garg, M K; Gupta, Sushil; Khurana, A K; Narang, Archna; Shukla, Manoj; Arora, Preeti; Chadha, Aditi; Nayak, Deb Datta; Manchanda, R K

2017-07-26

Population specific data and influence of sub-clinical hypothyroidism on insulin like growth factor-1 (IGF-1) and its binding protein-3 (IGFBP-3) in Indian children is lacking. This study was undertaken to evaluate serum IGF-1 and IGFBP-3 and their correlation with age, gender, pubertal status and thyroid functions. A total of 840 apparently healthy school girls aged 6-18 years, were recruited for the study and underwent assessment of height, weight, body mass index, pubertal status and serum T3, T4, TSH, IGF-1, IGFBP-3 and IGF-1/IGFBP-3 molar ratio. The mean serum levels of IGF-1, IGFBP-3 levels and IGF-1/IGFBP-3 molar ratio were 381.8±240.5 ng/mL, 4.19±2.08 μg/mL and 40.5±37.2%, respectively. The serum IGF-1 and IGF-1/IGFBP-3 molar ratio increased significantly (pIGF-1 and molar ratio of IGF-1/IGFBP-3 increased significantly with pubertal maturation from stage 1 to 3 and were higher in overweight girls compared to normal weight and obese girls. The growth factors were no different in girls with or without subclinical hypothyroidism. There was no significant impact of age on IGF-1 and IGFBP-3 in pre-pubertal girls. A sudden marked increase at 11 years followed by a gradual rise in growth factors till 16 years is indicative of pubertal initiation and maturation. Subclinical hypothyroidism did not influence growth factors in girls.

The Initiation of Dating in Adolescence : The Effect of Parental Divorce. The TRAILS Study

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Ivanova, Katya; Mills, Melinda; Veenstra, Rene

2011-01-01

This study examined the effect of parental divorce on the time it took adolescents to initiate their first romantic relationships. Individual differences in temperament and pubertal development and the age of the adolescent at the time of divorce were also taken into account. Hypotheses were tested

Rope skipping increases bone mineral density at calcanei of pubertal girls in Hong Kong: A quasi-experimental investigation.

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Amy S Ha

Full Text Available Bone mineral accrual during puberty is important, especially in girls, because it is related to reduced risks of osteoporosis in adulthood. Previous research has shown that jumping or plyometric exercises may be effective in increasing bone mineral density in adolescents. Rope skipping is a form of activity that involves jumping, thus regular skipping may also increase bone mineral density in pubertal girls. To this end, we conducted a quasi-experimental to examine the effects of rope skipping on girls' bone mineral density and cardiovascular fitness. 176 Hong Kong girls (age = 12.23 ± 1.80 years at baseline were recruited to take part in the study. Bone density at their forearms and calcanei were measured twice over two academic years (mean time between visits was 10.3 months. Using multilevel modeling analyses and adjusting for participants' height and physical activity, we found that girls who participated in weekly rope skipping activities, compared to those who did not, had higher levels of bone density at the calcanei (B = 0.023, p < .01. However, no differences were found for bone density at forearms or participants' cardiovascular fitness. The rates of change of these variables across time were also not significantly different. Results suggest that regular rope skipping may increase girls' bone density at the lower extremities, irrespective of the amount of self-report physical activity. However, further research is required to examine the potential dose-response relation between skipping behaviors and the measured outcomes.

The effects of puberty on white matter development in boys.

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Menzies, Lara; Goddings, Anne-Lise; Whitaker, Kirstie J; Blakemore, Sarah-Jayne; Viner, Russell M

2015-02-01

Neuroimaging studies demonstrate considerable changes in white matter volume and microstructure during adolescence. Most studies have focused on age-related effects, whilst puberty-related changes are not well understood. Using diffusion tensor imaging and tract-based spatial statistics, we investigated the effects of pubertal status on white matter mean diffusivity (MD) and fractional anisotropy (FA) in 61 males aged 12.7-16.0 years. Participants were grouped into early-mid puberty (≤Tanner Stage 3 in pubic hair and gonadal development; n=22) and late-post puberty (≥Tanner Stage 4 in pubic hair or gonadal development; n=39). Salivary levels of pubertal hormones (testosterone, DHEA and oestradiol) were also measured. Pubertal stage was significantly related to MD in diverse white matter regions. No relationship was observed between pubertal status and FA. Regression modelling of MD in the significant regions demonstrated that an interaction model incorporating puberty, age and puberty×age best explained our findings. In addition, testosterone was correlated with MD in these pubertally significant regions. No relationship was observed between oestradiol or DHEA and MD. In conclusion, pubertal status was significantly related to MD, but not FA, and this relationship cannot be explained by changes in chronological age alone. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Interaction of Pubertal Development and Metabolic Control in Adolescents with Type 1 Diabetes Mellitus

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M. Plamper

2017-01-01

Full Text Available Background. In T1DM, delayed pubertal development and reduced final height are associated with inadequate metabolic control. Objective. To assess whether T1DM affects pubertal growth spurt and whether metabolic control during puberty is gender-related. Methods. Using a large multicentre database, longitudinal data from 1294 patients were analysed. Inclusion criteria: complete records of height and HbA1c from the age of seven to 16 years. Exclusion criteria: other significant chronic diseases and medications, T1DM duration less than three months, and initial BMI 97th percentile. Results. Growth velocity (GV was impaired with a significant reduction of peak GV by 1.2 cm in boys. HbA1c increase during male puberty was lower except for a period of 1.5 years. The highest HbA1c increase in boys coincided with maximum growth spurt. In girls, the highest HbA1c increase was observed during late puberty. Even though there is impaired GV, both sexes reach a height at 16 years of age which corresponds to the background population height. Conclusion. Worsening of metabolic control is sex-discordant and associated with gender-specific alterations of GV. However, the vast majority of boys and girls with T1DM seems to reach normal height at the age of 16 years.

Genetic Variation of Follicle-Stimulating Hormone Action Is Associated With Age at Testicular Growth in Boys

DEFF Research Database (Denmark)

Busch, Alexander S; Hagen, Casper P; Main, Katharina M

2017-01-01

Context: Although genetic factors play a pivotal role in male pubertal timing, genome-wide association studies have identified only a few loci. Genetic variation of follicle-stimulating hormone (FSH) action affects adult reproductive parameters and female pubertal timing. Objective: To investigate...... effective FSH action. Effects explained 1.7% (Denmark) and 1.5% (Chile) of the variance. In addition, BMI z score was negatively associated with pubertal timing (β = -0.35 years in both cohorts), explaining 17.2% (Denmark) and 7.2% (Chile) of the variance. Conclusion: In two ethnically distinct populations...

Percentiles of fasting serum insulin, glucose, HbA1c and HOMA-IR in pre-pubertal normal weight European children from the IDEFICS cohort.

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Peplies, J; Jiménez-Pavón, D; Savva, S C; Buck, C; Günther, K; Fraterman, A; Russo, P; Iacoviello, L; Veidebaum, T; Tornaritis, M; De Henauw, S; Mårild, S; Molnár, D; Moreno, L A; Ahrens, W

2014-09-01

The aim of this study is to present age- and sex-specific reference values of insulin, glucose, glycosylated haemoglobin (HbA1c) and the homeostasis model assessment to quantify insulin resistance (HOMA-IR) for pre-pubertal children. The reference population consists of 7074 normal weight 3- to 10.9-year-old pre-pubertal children from eight European countries who participated in at least one wave of the IDEFICS ('identification and prevention of dietary- and lifestyle-induced health effects in children and infants') surveys (2007-2010) and for whom standardised laboratory measurements were obtained. Percentile curves of insulin (measured by an electrochemiluminescence immunoassay), glucose, HbA1c and HOMA-IR were calculated as a function of age stratified by sex using the general additive model for location scale and shape (GAMLSS) method. Levels of insulin, fasting glucose and HOMA-IR continuously show an increasing trend with age, whereas HbA1c shows an upward trend only beyond the age of 8 years. Insulin and HOMA-IR values are higher in girls of all age groups, whereas glucose values are slightly higher in boys. Median serum levels of insulin range from 17.4 and 13.2 pmol l(-1) in 3-HOMA-IR, median values range from 0.5 and 0.4 in 3-<3.5-year-old girls and boys to 1.7 and 1.4 in 10.5-<11-year-old girls and boys, respectively. Our study provides the first standardised reference values for an international European children's population and provides the, up to now, largest data set of healthy pre-pubertal children to model reference percentiles for markers of insulin resistance. Our cohort shows higher values of Hb1Ac as compared with a single Swedish study while our percentiles for the other glucose metabolic markers are in good accordance with previous studies.

[Relevant factors of early puberty timing in urban primary schools in Chongqing].

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Luo, Yan; Liu, Qin; Wen, Yi; Liu, Shudan; Lei, Xun; Wang, Hong

2016-05-01

To investigate the status of puberty timing and relevant factors of early puberty timing in children from grade one to four in urban primary schools of Chongqing. According to the purposive sample method, four urban primary schools in Chongqing were selected and of which 1471 children from grade one to four who have obtained informed consent were recruited. Questionnaire survey on social-demographic characteristics and family environment (e.g., age, parents' relationship, diet and lifestyle, etc), and Pubertal Development Scale (PDS) survey and physical examination (measurements of height, weight, pubertal development status, etc) were conducted. P25, P50, P75 ages of each important pubertal event were calculated by probit regression. Univariate and multivariate analysis were used to analyze relevant factors. The detection rate of early puberty timing was 17.7%, and the median ages of the onset of breast and testicular development were 10.77 and 11.48 years old, respectively. Multivariate logistic regression showed that early puberty timing occurred more likely in girls than in boys (OR = 0.561, 95% CI 0.406-0.774), and bad relationship between parents (OR = 1.320, 95% CI 1.007-1.729) and hair-products-use (OR = 1.685, 95%, CI 1.028-2.762) were risk factors of early puberty timing. Early onset of puberty in urban Chongqing is still exist. Gender, parents' relationship, and hair-products-use have an essential impact on early puberty timing.

Pubertal-related changes in hypothalamic-pituitary-adrenal axis reactivity and cytokine secretion in response to an immunological stressor.

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Goble, K H; Bain, Z A; Padow, V A; Lui, P; Klein, Z A; Romeo, R D

2011-02-01

Pubertal development is marked by profound changes in stress reactivity. For example, following a brief stressor, such as foot shock, ether inhalation or restraint, prepubertal rats display a prolonged adrenocorticotrophic hormone (ACTH) and corticosterone response that takes twice as long to return to baseline compared to adults. Pubertal-related differences in the recovery of the hormonal stress response following a more protracted systemic stressor, such as an immunological challenge, have not yet been investigated. Moreover, it is unclear whether an immunological stressor leads to a differential cytokine response in animals before and after pubertal maturation. To examine these issues, we used a single injection of lipopolysaccharide (LPS; 0.1 mg/kg) to induce a hormonal stress and innate immune response and measured plasma ACTH, corticosterone, and the pro-inflammatory cytokines interleukin (IL)-1β and IL-6 in prepubertal and adult male rats 0, 2, 4, 6, 8, or 24 h after LPS exposure. In a follow-up experiment, we assessed neural activation, as indexed by FOS immunohistochemistry, in the paraventricular nucleus of the hypothalamus (PVN) in prepubertal and adult males 0, 4, 8, or 24 h after a 0.1 mg/kg injection of LPS. By contrast to the prolonged response observed in prepubertal animals following a variety of acute stressors, we found that corticosterone and IL-6 responses induced by LPS recover toward baseline faster in prepubertal compared to adult rats. Along with these different peripheral responses, we also found that LPS-induced neural activation in the PVN of prepubertal animals showed a faster return to baseline compared to adults. Together, these data indicate that prepubertal and adult animals react in distinct ways, both peripherally and centrally, to an immunological stressor. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

Association of insulin-like growth factor-1 and IGF binding protein-3 with 25-hydroxy vitamin D in pre-pubertal and adolescent Indian girls.

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Marwaha, Ramank K; Garg, M K; Gupta, Sushil; Ganie, Mohd Ashraf; Gupta, Nandita; Narang, Archna; Shukla, Manoj; Arora, Preeti; Singh, Annie; Chadha, Aditi; Mithal, Ambrish

2018-03-28

There is a high prevalence of vitamin D deficiency (VDD) in India. Molecular mechanisms suggest a strong relationship between vitamin D and growth factors. However, there is a paucity of literature with regard to a relationship between insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3) and vitamin D particularly in subjects with VDD. The objective of the study was to assess the relationship between growth factors and serum vitamin D-parathormone (PTH) status in school girls and study the impact of vitamin D supplementation on growth factors in pre-pubertal girls with VDD. Our study subjects were apparently healthy school girls aged 6-18 years. The baseline height, weight, body mass index (BMI), pubertal status, serum 25-hydroxy vitamin D (25OHD), PTH, IGF-1 and IGFBP-3 were assessed in 847 girls aged 6-18 years and in 190 pre-pubertal girls with VDD following supplementation. The mean age, BMI and serum 25OHD of girls were 11.5±3.2 years, 18.7±4.8 kg/m2 and 9.9±5.6 ng/mL, respectively. VDD was observed in 94.6% of girls. Unadjusted serum IGF-1 levels and IGF-1/IGFBP-3 molar ratio were significantly higher in girls with severe VDD as compared to girls with mild-to-moderate VDD. However, these differences disappeared when adjusted for age, height or sexual maturation. The serum IGF-1 and IGFBP-3 levels increased significantly post supplementation with vitamin D. There were no differences in serum IGF-1 levels and the IGF-1/IGFBP-3 molar ratio among VDD categories when adjusted for age, height and sexual maturation in girls. Vitamin D supplementation resulted in a significant increase in serum IGF-1 levels in VDD pre-pubertal girls.

Phthalate and bisphenol A exposure during in utero windows of susceptibility in relation to reproductive hormones and pubertal development in girls.

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Watkins, Deborah J; Sánchez, Brisa N; Téllez-Rojo, Martha Maria; Lee, Joyce M; Mercado-García, Adriana; Blank-Goldenberg, Clara; Peterson, Karen E; Meeker, John D

2017-11-01

Over the past several decades, the age of pubertal onset in girls has shifted downward worldwide. As early pubertal onset is associated with increased risky behavior and psychological issues during adolescence and cardiometabolic disease and cancer in adulthood, this is an important public health concern. Exposure to endocrine disrupting chemicals during critical windows of in utero development may play a role in this trend. Our objective was to investigate trimester-specific phthalate and BPA exposure in relation to pubertal development among girls in the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohort. We measured maternal urinary phthalate metabolites and BPA in samples collected during the first, second, and third trimesters of pregnancy. To assess reproductive development among their female children, we measured serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG), and assessed sexual maturation, including Tanner staging for breast and pubic hair development and menarche status, at age 8-13 years (n = 120). We used linear and logistic regression to examine measures of trimester-specific in utero exposure as predictors of peripubertal hormone levels and pubertal onset, respectively. In secondary analyses, we evaluated estimated exposure at the midpoint of the first trimester and rates of change in exposure across pregnancy in relation to outcomes. Several phthalate metabolites measured throughout in utero development were associated with higher serum testosterone concentrations, while a number of metabolites measured in the third trimester were associated with higher DHEA-S. For example, an interquartile range (IQR) increase in mean monoethyl phthalate (MEP) levels across pregnancy was associated with 44% higher peripubertal testosterone (95% CI: 13-83%), while an IQR increase in di-2-ethylhexyl phthalate metabolites (ΣDEHP) specifically in the third trimester

Early Pubertal Maturation and Internalizing Problems in Adolescence: Sex Differences in the Role of Cortisol Reactivity to Interpersonal Stress

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Natsuaki, Misaki N.; Klimes-Dougan, Bonnie; Ge, Xiaojia; Shirtcliff, Elizabeth A.; Hastings, Paul D.; Zahn-Waxler, Carolyn

2009-01-01

An accumulating body of literature has shown a link between early pubertal maturation and internalizing problems, particularly among girls. Our knowledge is, however, limited with regard to what accounts for this association. Based on a hypothesis that early maturing girls have heightened stress sensitivity that increases the risk of internalizing…

Cardiovascular risk factors in pre-pubertal schoolchildren in Angola.

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Silva, Amílcar B; Capingana, Daniel P; Magalhães, Pedro; Gonçalves, Mauer A; Molina, Maria Del Carmen B; Rodrigues, Sërgio L; Baldo, Marcelo P; Mateus, Miguel S; Mill, Josë Geraldo

The incidence of obesity is increasing worldwide, especially in countries with accelerated economic growth. We determined the prevalence of and associations between overweight/obesity and cardiovascular risk factors in pre-pubertal (seven- to 11-year-old) schoolchildren (both genders, n = 198) in Luanda, Angola. Biochemical (fasting blood) and clinical examinations were obtained in a single visit. Data are reported as prevalence (95% confidence intervals) and association (r, Pearson). Prevalence of overweight/obesity was 17.7% (12.4- 23.0%), high blood pressure (BP > 90% percentile) was 14.6% (9.7-19.5%), elevated glucose level was 16.7% (11.5-21.9%) and total cholesterol level > 170 mg/dl (4.4 mmol/l) was 69.2% (62.8-75.6%). Significant associations between body mass index (BMI) and systolic and diastolic BP (r = 0.46 and 0.40, respectively; p Angola and fat accumulation was directly associated with blood pressure increase but not with other cardiovascular risk factors.

The effects of maxillary protraction and its long-term stability--a clinical trial in Chinese adolescents.

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Chen, LinLing; Chen, RongJing; Yang, YiMing; Ji, GuoPing; Shen, Gang

2012-02-01

The purpose of this study was to evaluate the effect of reverse pull headgear (RPHG) in the treatment of Class III malocclusions in the late mixed and early permanent dentition and its long-term stability at the time when facial growth was close to completion. The treatment group comprised 22 subjects (12 males and 10 females, mean age: 11.38 ± 0.69 years). The control group included 17 subjects (7 males and 10 females, mean age: 11.54 ± 1.07 years). The mean RPHG treatment time was 1.5 ± 0.95 years and the observation time for the control group was 1.75 ± 0.83 years. For each subject, lateral cephalograms were obtained before (T1) and after (T2) treatment or observation. These cephalograms were traced and analyzed and the differences between T1 and T2 values were examined with paired t-tests. Of the 22 treated cases, 10 patients were followed up until at the mean age of 16.18 years (T3). Since there was no relapse in anterior crossbite, the long-term effects of RPHG were evaluated by measuring the maxillary and mandibular skeletal changes. The follow-up patients were divided into two groups based on the change in ANB: a stable group (decrease in ANB 2 degrees). The skeletal effects of RPHG in treating Class III anomalies just before or at the beginning of the pubertal growth spurt include protraction of the maxilla and dentition and inhibition of forward growth of the mandible. With regard to the long-term change, a slight alteration in the position of the maxilla and in the position and growth direction of the mandible resulted in a slight decrease in ANB in the stable group. The slight retrusion in the maxilla, combined with the significant protrusion in the mandible and the more horizontal mandibular growth direction, resulted in a decrease in ANB in the unstable group. This indicated that the maxilla remained relatively stable and that the unstable factor was continuing mandibular growth during the pubertal and post-pubertal period. For patients with an

The relations of age and pubertal development with cortisol and daily stress in youth at clinical risk for psychosis.

Science.gov (United States)

Moskow, Danielle M; Addington, Jean; Bearden, Carrie E; Cadenhead, Kristin S; Cornblatt, Barbara A; Heinssen, Robert; Mathalon, Daniel H; McGlashan, Thomas H; Perkins, Diana O; Seidman, Larry J; Tsuang, Ming T; Cannon, Tyrone D; Woods, Scott W; Walker, Elaine F

2016-04-01

Prodromal syndromes often begin in adolescence - a period of neurodevelopmental changes and heightened stress sensitivity. Research has shown elevated stress and cortisol in individuals at clinical high risk (CHR) for psychosis. This cross-sectional study examined relations of age and pubertal status with cortisol and self-reported stress in healthy controls (HCs) and CHR adolescents. It was hypothesized that the relations of age and pubertal stage with cortisol and stress would be more pronounced in CHR youth. Participants were 93 HCs and 348 CHR adolescents from the North American Prodrome Longitudinal Study (NAPLS). At baseline, measures of stress (Daily Stress Inventory - DSI), Tanner stage (TS), and salivary cortisol were obtained. ANCOVA revealed increased DSI scores with age for both groups, and higher DSI scores in CHR adolescents than HCs, with a more pronounced difference for females. Contrary to prediction, with age controlled, HCs showed greater TS-related DSI increases. Analysis of cortisol showed no significant interactions, but a main effect of age and a trend toward higher cortisol in the CHR group. Correlations of cortisol with TS were higher in HC than CHR group. Stress measures increased with age in HC and CHR adolescents, and DSI scores also increased with TS in HCs. The results do not support a more pronounced age or TS increase in stress measures in CHR adolescents, but instead suggest that stress indices tend to be elevated earlier in adolescence in the CHR group. Potential determinants of findings and future directions are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

The Initiation of Dating in Adolescence: The Effect of Parental Divorce. The TRAILS Study

Science.gov (United States)

Ivanova, Katya; Mills, Melinda; Veenstra, Rene

2011-01-01

This study examined the effect of parental divorce on the time it took adolescents to initiate their first romantic relationships. Individual differences in temperament and pubertal development and the age of the adolescent at the time of divorce were also taken into account. Hypotheses were tested using event history analysis with a sample of…

Accuracy of dental development for estimating the pubertal growth spurt in comparison to skeletal development: a systematic review and meta-analysis.

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Bittencourt, MarcosAlan Vieira; Cericato, GrazielaOro; Franco, Ademir; Girão, RafaelaSilva; Lima, Anderson Paulo Barbosa; Paranhos, LuizRenato

2018-05-01

This study aimed to search for scientific evidence concerning the accuracy of dental development for estimating the pubertal growth spurt. It was conducted according to the statements of PRISMA. An electronic search was performed in six databases, including the grey literature. The PICOS strategy was used to define the eligibility criteria and only observational studies were selected. Out of 1,416 identified citations, 10 articles fulfilled the criteria and were included in this systematic review. The association between dental development and skeletal maturity was considered strong in seven studies, and moderate in two, although the association with the pubertal growth spurt had been verified in only four articles. According to half of the studies, the tooth that provided the greater association with the ossification centres was the lower canine. The meta-analysis performed also indicated a positive association, being stronger in females [0.725 (0.649-0.808)]. However, when the method used for dental evaluation was considered, it was possible to verify greater correlation coefficients for Nolla [0.736 (0.666-0.814)] than for Demirjian [0.631 (0.450-0.884)], at the boys sample. The heterogeneity test reached high values (Q = 51.00), suggesting a potential bias within the studies. Most of individual studies suggested a strong correlation between dental development and skeletal maturation, although the association with the peakof pubertal growth spurtwas clearly cited only in some of them. However, due to the high heterogeneity found among the studies included in this meta-analysis, a pragmatic recommendation about the use of dental stages is not possible.

Evaluation of apoptotic- and autophagic-related protein expressions before and after IVM of fresh, slow-frozen and vitrified pre-pubertal mouse testicular tissue.

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Dumont, L; Chalmel, F; Oblette, A; Berby, B; Rives, A; Duchesne, V; Rondanino, C; Rives, N

2017-11-01

Do freezing and in vitro culture procedures enhance the expression of proteins involved in apoptotic or autophagic pathways in murine pre-pubertal testicular tissue? IVM strongly modified apoptosis- and autophagy-related relative protein levels in mice testicular tissue whereas the impact of cryopreservation procedures was minimal at the end of the culture. In vitro spermatogenesis remains a challenging technical issue as it imposes to find a very close balance between survival and death of germ cell natural precursors (i.e. gonocytes and spermatogonia), which will eventually undergo a complete spermatogenesis close to in vivo conditions. The establishment of efficient culture conditions coupled with suitable cryopreservation procedures (e.g. controlled slow freezing [CSF] and solid surface vitrification [SSV]) of pre-pubertal testicular tissue is a crucial step in the fields of fertility preservation and restoration to improve the spermatic yield obtained in vitro. Here, we study cryopreservation procedures (i.e. CSF or SSV) and the impact of culture media compositions. A first set of 66 mouse pre-pubertal testes were directly cultured during 30, 36, 38 and 60 days (D) from 2.5 to 6.5-day-old CD-1 mice to evaluate the impact of time-aspect of culture and to endorse the reverse phase protein microarrays (RPPM) technique as an adapted experimental tool for the field of in vitro spermatogenesis. Ninety others fresh, slow-frozen and vitrified pre-pubertal testes were cultured during 30 days for the principal study to evaluate the impact of cryopreservation procedures before and after culture. Thirty-four testes dissected from 2.5, 6.5, 36.5, 40.5, 42.5 and 62.5 days postpartum (dpp) mice, corresponding to the time frames of spermatogenesis orchestrated in vitro, were used as in vivo controls. After in vitro culture, testicular tissue samples originated from 2.5 or 6.5-day-old CD-1 male mice were analyzed using RPPM. This targeted proteomic technique allowed us to

Timing of Puberty in Overweight Versus Obese Boys.

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Lee, Joyce M; Wasserman, Richard; Kaciroti, Niko; Gebremariam, Achamyeleh; Steffes, Jennifer; Dowshen, Steven; Harris, Donna; Serwint, Janet; Abney, Dianna; Smitherman, Lynn; Reiter, Edward; Herman-Giddens, Marcia E

2016-02-01

Studies of the relationship of weight status with timing of puberty in boys have been mixed. This study examined whether overweight and obesity are associated with differences in the timing of puberty in US boys. We reanalyzed recent community-based pubertal data from the American Academy of Pediatrics' Pediatric Research in Office Settings study in which trained clinicians assessed boys 6 to 16 years for height, weight, Tanner stages, testicular volume (TV), and other pubertal variables. We classified children based on BMI as normal weight, overweight, or obese and compared median age at a given Tanner stage or greater by weight class using probit and ordinal probit models and a Bayesian approach. Half of boys (49.9%, n = 1931) were white, 25.8% (n = 1000) were African American, and 24.3% (n = 941) were Hispanic. For genital development in white and African American boys across a variety of Tanner stages, we found earlier puberty in overweight compared with normal weight boys, and later puberty in obese compared with overweight, but no significant differences for Hispanics. For TV (≥3 mL or ≥4 mL), our findings support earlier puberty for overweight compared with normal weight white boys. In a large, racially diverse, community-based sample of US boys, we found evidence of earlier puberty for overweight compared with normal or obese, and later puberty for obese boys compared with normal and overweight boys. Additional studies are needed to understand the possible relationships among race/ethnicity, gender, BMI, and the timing of pubertal development. Copyright © 2016 by the American Academy of Pediatrics.

Effect of Aegle marmelos and Murraya koenigii in treatment of delayed pubertal buffaloes heifers

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Mohan M. Baitule

2016-12-01

. koenigii alone, were found effective in fertility improvement in delayed pubertal buffalo heifers by increasing ovulation and conception rate.

Age, puberty, body dissatisfaction, and physical activity decline in adolescents. Results of the German Health Interview and Examination Survey (KiGGS

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Finne Emily

2011-10-01

Full Text Available Abstract Background Physical activity (PA shows a marked decline during adolescence. Some studies have pointed to pubertal status or timing as possible PA determinants in this age group. Furthermore, it was supposed that the impact of pubertal changes on PA might be mediated by psychological variables like body dissatisfaction (BDS. Methods The 11- to 17-year-old subsample of the German Health Interview and Examination Survey (KiGGS was used (n = 6 813; 51.3% male, response rate = 66.6%. Through sex-specific sequential multinomial logistic regressions we analysed the univariate and independent associations of chronological age, absolute pubertal status, relative pubertal timing, and BDS with the frequency of PA. Results Chronological age showed a significantly negative association with PA in both sexes, independent of puberty. The odds of inactivity in contrast to nearly daily PA increased about 70% in boys and 35% in girls for each year of age, respectively. Adjusted for age and other possible confounders, inactivity was significantly less likely for boys in late pubertal stages (OR = 0.27, 95% CI = 0.09-0.78. The risk of inactivity was more than doubled in boys maturing earlier than peers in terms of relative pubertal timing (OR = 2.20, 95% CI = 1.36-3.56. No clear significant puberty effects were found in girls, but the inactivity was more likely for those with irregular menstruation (OR = 1.71, 95% CI = 1.06-2.75. BDS also contributed to the prediction of PA in both sexes. It partially mediated puberty effects in boys but not in girls. Conclusions Overall, chronological age was a far more important predictor of PA in German adolescents than absolute pubertal status or relative pubertal timing. Further possible explanatory variables like sociocultural influences, social support or increasing time requirements for education should be analysed in conjunction with chronological age in future studies.

Genital Involvement In Pre-Pubertal Pediatric Population: A Rare Aspect of Crohn’s Disease

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Qurratul Ann Warsi

2016-09-01

Full Text Available Crohn’s disease is an inflammatory bowel disease (IBD, characterized by chronic intestinal inflammation that causes the loss of immune tolerance leading to bizarre inflammatory signals and disruption of mucosal barriers. Environmental triggers and interaction of genetic determinants also play an indispensible role. In this case report, we present a pre-pubertal girl with intermittent and refractory genital swelling. We emphasize that Crohn’s disease must be considered in the differential diagnosis of recurrent, non-tender, erythematous and edematous lesions of the genital area. We conclude with future directions for diagnosing and managing vulvar Crohn’s disease in pediatric population.

Sex-specific mouse liver gene expression: genome-wide analysis of developmental changes from pre-pubertal period to young adulthood

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Conforto Tara L

2012-04-01

Full Text Available Abstract Background Early liver development and the transcriptional transitions during hepatogenesis are well characterized. However, gene expression changes during the late postnatal/pre-pubertal to young adulthood period are less well understood, especially with regards to sex-specific gene expression. Methods Microarray analysis of male and female mouse liver was carried out at 3, 4, and 8 wk of age to elucidate developmental changes in gene expression from the late postnatal/pre-pubertal period to young adulthood. Results A large number of sex-biased and sex-independent genes showed significant changes during this developmental period. Notably, sex-independent genes involved in cell cycle, chromosome condensation, and DNA replication were down regulated from 3 wk to 8 wk, while genes associated with metal ion binding, ion transport and kinase activity were up regulated. A majority of genes showing sex differential expression in adult liver did not display sex differences prior to puberty, at which time extensive changes in sex-specific gene expression were seen, primarily in males. Thus, in male liver, 76% of male-specific genes were up regulated and 47% of female-specific genes were down regulated from 3 to 8 wk of age, whereas in female liver 67% of sex-specific genes showed no significant change in expression. In both sexes, genes up regulated from 3 to 8 wk were significantly enriched (p p Ihh; female-specific Cdx4, Cux2, Tox, and Trim24 and may contribute to the developmental changes that lead to global acquisition of liver sex-specificity by 8 wk of age. Conclusions Overall, the observed changes in gene expression during postnatal liver development reflect the deceleration of liver growth and the induction of specialized liver functions, with widespread changes in sex-specific gene expression primarily occurring in male liver.

Physical activity, sedentary time, and sleep and the association with inflammatory markers and adiponectin in 8- to 11-year-old Danish children

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Nielsen, Mette Søndergaard; Quist, Jonas Salling; Chaput, Jean-Philippe

2016-01-01

the association between accelerometer determined moderate-to-vigorous physical activity (MVPA), sedentary time, and sleep (7 days/8 nights) and fasting C-reactive protein (CRP), interleukin-6 (IL-6), and adiponectin in 806 school children. A sleep variability score was calculated. RESULTS: MVPA was negatively...... associated with adiponectin in boys and girls (Psleep duration, sedentary time, age, fat mass index (FMI), and pubertal status. Sedentary time was positively associated with adiponectin in boys and girls (both Psleep duration...... with adiponectin in boys independent of age, FMI, and pubertal status (PSleep duration variability was positively associated with CRP in girls independent of all covariates (P

Dietary polyunsaturated fatty acid supplementation of young post-pubertal dairy bulls alters the fatty acid composition of seminal plasma and spermatozoa but has no effect on semen volume or sperm quality.

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Byrne, C J; Fair, S; English, A M; Holden, S A; Dick, J R; Lonergan, P; Kenny, D A

2017-03-01

The aim of this study was to examine the effects of dietary supplementation with rumen protected n-6 or n-3 polyunsaturated fatty acids (PUFA) on the quantity and quality of semen from young post-pubertal dairy bulls. Pubertal Holstein-Friesian (n = 43) and Jersey (n = 7) bulls with a mean ± s.e.m. age and bodyweight of 420.1 ± 5.86 days and 382 ± 8.94 kg, respectively, were blocked on breed, weight, age and semen quality (based on the outcomes of two pre-trial ejaculates) and randomly assigned to one of three treatments: (i) a non-supplemented control (CTL, n = 15), (ii) rumen-protected safflower (SO, n = 15), (iii) rumen-protected n-3 PUFA-enriched fish oil (FO, n = 20). Bulls were fed their respective diets, ad libitum for 12 weeks; individual intakes were recorded using an electronic feeding system for the initial 6 weeks of the feeding period. Semen was collected via electro-ejaculation at weeks -2, -1, 0, 7, 10, 11 and 12 relative to the beginning of the trial period (week 0). On collection, semen volume, sperm concentration and progressive linear motility (PLM) were assessed. On weeks -2, -1, 0, 10, 11, 12, semen was packaged into 0.25 mL straws and frozen using a programmable freezer. On weeks -1, 7 and 11; a sub-sample of semen was separated into sperm and seminal plasma, by centrifugation and stored at - 20 °C until analysis of lipid composition. Semen from 10 bulls per treatment were used for post-thaw analysis at weeks 10, 11 and 12 (3 straws per ejaculate). Sperm motility was analysed by computer assisted semen analysis (CASA). In addition, membrane fluidity, acrosome reaction and oxidative stress were assessed using flow cytometry. Sperm from bulls fed SO had a 1.2 fold higher total n-6 PUFA content at week 11 compared to week -1 (P semen volume, concentration or PLM of sperm when assessed either immediately following collection or post-thawing. Membrane fluidity and oxidative stress of sperm were also not affected by

Sex, age, pubertal development and use of oral contraceptives in relation to serum concentrations of DHEA, DHEAS, 17α-hydroxyprogesterone, Δ4-androstenedione, testosterone and their ratios in children, adolescents and young adults.

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Søeborg, Tue; Frederiksen, Hanne; Mouritsen, Annette; Johannsen, Trine Holm; Main, Katharina Maria; Jørgensen, Niels; Petersen, Jørgen Holm; Andersson, Anna-Maria; Juul, Anders

2014-11-01

The influence of sex, age, pubertal development and oral contraceptives on dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), testosterone (T), calculated free testosterone (fT), free androgen index (FAI) and selected ratios in 1798 serum samples from healthy children, adolescents and young adults was evaluated. Samples were analyzed by Turboflow-LC-MS/MS. Sex hormone-binding globulin was analyzed by immunoassay. All steroid metabolite concentrations were positively associated with age and pubertal development in both sexes and generally higher in males than in females except for Adione. The pubertal rise in T in males was more pronounced compared to females, reflecting contribution from the testes. Ratios between steroid metabolites varied and depended on sex and age. All ratios were lower during infancy compared to later in life. Use of oral contraceptives significantly lowered serum concentrations of all steroid metabolites, fT, FAI, the 17-OHP/Adione, the Adione/T and the DHEA/Adione ratios, but not the DHEA/DHEAS ratio. We provide reference ranges for DHEA, DHEAS, 17-OHP, Adione, T, fT, FAI and selected ratios in relation to sex, age and pubertal development. Use of oral contraceptives strongly influences adrenal steroidogenesis and should be considered when diagnosing and monitoring treatment of patients with disorders of sex development. Copyright © 2014 Elsevier B.V. All rights reserved.

Expression and localization of Indian hedgehog (Ihh) and parathyroid hormone related protein (PTHrP) in the human growth plate during pubertal development.

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Kindblom, J M; Nilsson, O; Hurme, T; Ohlsson, C; Sävendahl, L

2002-08-01

Indian Hedgehog (Ihh) has been reported to control the rate of cartilage differentiation during skeletal morphogenesis in rodents through a negative feedback loop involving parathyroid hormone related protein (PTHrP). The role of Ihh and PTHrP in the regulation of human epiphyseal chondrocytes is unknown. The aim of the current study was to examine the expression and localization of Ihh and PTHrP in the human growth plate at various pubertal stages. Growth plate biopsies were obtained from patients subjected to epiphyseal surgery and the expression of Ihh and PTHrP was detected by immunohistochemistry. We show that Ihh and PTHrP are expressed mainly in early hypertrophic chondrocytes in the human growth plate. The levels of expression of Ihh and PTHrP are higher in early stages of puberty than later. Our results suggest that Ihh and PTHrP are present in the human growth plate and that Ihh and PTHrP may be involved in the regulation of pubertal growth in humans.

Age-dependent exposure to radioactive iodine (131I) in the thyroid and total body of newborn, pubertal and adult fischer 344 rats

International Nuclear Information System (INIS)

Nitta, Yumiko; Fujimoto, Nariaki; Kamiya, Kenji; Hoshi, Masaharu; Endo, Satoru

2001-01-01

Female rats of the Fischer 344 strain at ages of 1, 4 and 9 weeks were exposed to 131 I intraperitoneally with activities of 0.38, 1.03 and 3.42 kBq per gram of body weight under the condition of iodine deficiency. The absorbed doses in the thyroid increased linearly depending on the injected activities. Irradiation at 1 week old caused heavier exposure than those at 4 and 9 weeks old by 7.5 and 7.7 times, respectively; however, damage of the thyroid tissue was more obvious in the 4-week-old groups than in the 1-week-old groups. The absorbed doses in the total body were proportional to the square root of the injected activities. The one-week-old groups were exposed more heavily than the 4- and 9-week-old groups by 3.6 and 4.7 times, respectively, shown by the slow excretion of 131 I with the values of effective half-life of 131 I activity (T eff ). An IDD-treatment was not so effective to enhance the 131 I absorption in the total body, as in the thyroid. No matter how the iodine concentration in the blood changed, the 1-week-old groups could not react to normalize the level. We drew standard curves, which enabled us to estimate the absorbed doses in the thyroid and the total body in the case of the injected activities of 131 I for the newborn, pubertal and adult rats. (author)

Attachment, parenting styles and bullying during pubertal years.

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van der Watt, Ronél

2014-01-01

Research that focuses on combining attachment, parenting styles, bullying and the reciprocal nature thereof in the parent-adolescent and peer relationships is limited. The bio-psychosocial changes that adolescents experience open up broader social realities and are perceived differently by parents and adolescents. Attachment processes and parenting styles may elicit dissimilar perceptions. These processes are also associated with the multifaceted dynamics of bullying. The aim of the article is to advocate for research on the possible link between the implications of attachment, parenting styles and bullying. Exploring the association between attachment, parenting styles and bullying can deepen the understanding of the developmental challenges within the parent-adolescent relationship, add insight to the different perceptions of adolescents and parents, and complement intervention programmes accordingly. Firstly, this article outlines bio-psychosocial changes in the pubertal years as related to the social realities of the adolescent. Secondly, a discussion on the concepts 'attachment', 'parenting styles', 'bullying', and the potential link between these concepts will follow. Thirdly, an outline of the clinical implications of the apparent association between these concepts is given. The article concludes with recommendations that researchers can consider while exploring the relationship between attachment, parenting styles, and bullying and the delineation thereof in the parent-adolescent relationship.

Assessment of circulating sex steroid levels in prepubertal and pubertal boys and girls by a novel ultrasensitive gas chromatography-tandem mass spectrometry method

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Courant, Frédérique; Aksglæde, Lise; Antignac, Jean-Philippe

2010-01-01

Estrogens and androgens play key roles for pubertal onset and sexual maturation. Most currently used immunoassays are not sensitive enough to accurately measure the low circulating levels of sex steroids in children without any signs of puberty. However, this does not exclude that sex steroids ha...

Trends in puberty timing in humans and environmental modifiers

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Toppari, Jorma; Juul, Anders

2010-01-01

Secular trends in timing of puberty appear to continue although under-nutrition has not been any longer a limiting factor for pubertal development. Now obesity and other environmental reasons have been suspected to cause this trend, and endocrine disrupting chemicals have become into focus...... as possible contributors. Epidemiological studies on endocrine disrupters are still scarce and show only weak associations between exposures and timing of puberty. Since genetic background explains 50-80% of variability in the timing of puberty, it is not surprising that the observed environmental effects...... are rather modest when individual exposures are assessed. Despite that, some exposures have been reported to be associated to early (e.g., polybrominated biphenyls) or delayed (e.g., lead) puberty. Here we shortly review the available data on recent trends in timing of puberty and the possible role...

Normal Pubertal Development in Daughters of Women With PCOS: A Controlled Study.

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Legro, Richard S; Kunselman, Allen R; Stetter, Christy M; Gnatuk, Carol L; Estes, Stephanie J; Brindle, Eleanor; Vesper, Hubert W; Botelho, Julianne C; Lee, Peter A; Dodson, William C

2017-01-01

Daughters of women with polycystic ovary syndrome (PCOS) are thought to be at increased risk for developing stigmata of the syndrome, but the ontogeny during puberty is uncertain. We phenotyped daughters (n = 76) of mothers with PCOS and daughters (n = 80) from control mothers for reproductive and metabolic parameters characteristic of PCOS. We performed a matched case/control study at Penn State Hershey Medical Center that included non-Hispanic, white girls 4 to 17 years old. We obtained birth history, biometric, ovarian ultrasounds, whole-body dual-energy X-ray absorptiometry scan for body composition, 2-hour glucose challenged salivary insulin levels, and two timed urinary collections (12 hours overnight and 3 hours in the morning) for gonadotropins and sex steroids. We measured integrated urinary levels of adrenal (dehydroepiandrosterone sulfate) and ovarian [testosterone (TT)] steroids. Other endpoints included integrated salivary insulin levels and urinary luteinizing hormone levels. There were no differences in detection rates or mean levels for gonadotropins and sex steroids in timed urinary collections between PCOS daughters and control daughters, nor were there differences in integrated salivary insulin levels. Results showed that 69% of Tanner 4/5 PCOS daughters vs 31% of control daughters had hirsutism defined as a Ferriman-Gallwey score >8 (P = 0.04). There were no differences in body composition as determined by dual-energy X-ray absorptiometry between groups in the three major body contents (i.e., bone, lean body mass, and fat) or in ovarian volume between groups. Matched for pubertal stage, PCOS daughters have similar levels of urinary androgens and gonadotropins as well as glucose-challenged salivary insulin levels. Copyright © 2017 by the Endocrine Society

Combined Treatment with Gonadotropin-releasing Hormone Analog and Anabolic Steroid Hormone Increased Pubertal Height Gain and Adult Height in Boys with Early Puberty for Height.

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Tanaka, Toshiaki; Naiki, Yasuhiro; Horikawa, Reiko

2012-04-01

Twenty-one boys with a height of 135 cm or less at onset of puberty were treated with a combination of GnRH analog and anabolic steroid hormone, and their pubertal height gain and adult height were compared with those of untreated 29 boys who enter puberty below 135 cm. The mean age at the start of treatment with a GnRH analog, leuprorelin acetate depot (Leuplin(®)) was 12.3 yr, a mean of 1.3 yr after the onset of puberty, and GnRH analog was administered every 3 to 5 wk thereafter for a mean duration of 4.1 yr. The anabolic steroid hormone was started approximately 1 yr after initiation of treatment with the GnRH analog. The mean pubertal height gain from onset of puberty till adult height was significantly greater in the combination treatment group (33.9 cm) than in the untreated group (26.4 cm) (ppenis and pubic hair is promoted by the anabolic steroid hormone, no psychosocial problems arose because of delayed puberty. No clinically significant adverse events appeared. Combined treatment with GnRH analog and anabolic steroid hormone significantly increased height gain during puberty and adult height in boys who entered puberty with a short stature, since the period until epiphyseal closure was extended due to deceleration of the bone age maturation by administration of the GnRH analog and the growth rate at this time was maintained by the anabolic steroid hormone.

The timing of normal puberty and the age limits of sexual precocity

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Parent, Anne-Simone; Teilmann, Grete; Juul, Anders

2003-01-01

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western European...

The timing of normal puberty and the age limits of sexual precocity

DEFF Research Database (Denmark)

Parent, Anne-Simone; Teilmann, Grete; Juul, Anders

2003-01-01

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western Europe...

Bone turnover markers during pubertal development: relationships with growth factors and adipocytokines.

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Jürimäe, Jaak; Mäestu, Jarek; Jürimäe, Toivo

2010-01-01

The rapid increase in skeletal mass that occurs during puberty is caused by increases in longitudinal growth as well as cortical thickness. The measurement of growth changes during puberty using two-dimensional (dual-energy X-ray absorptiometry) and/or three-dimensional (computed tomography, magnetic resonance imaging) measurement devices provides only a static representation of bone tissue parameters. The measurement of bone turnover markers provides a more dynamic picture of the nature of bone tissue that can be repeated at much shorter intervals during puberty. The bone turnover markers are products of osteoblasts and osteoclasts which can be measured in urine or blood. The increase in different markers of bone turnover coincides with the pubertal growth spurt and thereafter markers decline until they converge into adult values. The initiation of puberty is accompanied by increases in androgens and estrogens. The effects of sex hormones on bone mineral accrual are mediated mainly by growth hormone and insulin-like growth factor-1, but they also exert a direct effect on bone metabolism. Important determinants of bone mineral accrual during puberty include optimal nutritional status, body composition parameters and physical activity pattern. All of these determinants are related to the state of energy balance, while peripheral indicators of energy balance, such as different growth factors and adipocytokines, may also have a positive influence of the growing skeleton. Taken together, bone mineral accrual during puberty is a complex interaction between physical activity pattern, various body composition parameters, specific growth factors and adipocytokines, and also sex hormones. Copyright © 2010 S. Karger AG, Basel.

Isolated torsion of the fallopian tube in a menopausal woman and a pre-pubertal girl: two case reports

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Toyoshima, Masafumi; Mori, Hikaru; Kudo, Kei; Yodogawa, Yuki; Sato, Kazuyo; Kudo, Takako; Igeta, Saori; Makino, Hiromitsu; Shima, Takashi; Matsuura, Rui; Ishigaki, Nobuko; Akagi, Kozo; Takeyama, Yoichi; Iwahashi, Hideki; Yoshinaga, Kosuke

2015-01-01

Introduction Isolated torsion of the fallopian tube without an ovarian abnormality is an uncommon event, with an incidence of approximately 1 in 1,500,000 females. Isolated torsion of the fallopian tube occurs mostly in reproductive-aged women, and is thus extremely rare in menopausal women and pre-pubertal girls. Case presentations In case 1, 63-year-old Japanese woman presented with a 2-day history of acute lower abdominal pain. Menopause occurred at 53?years of age. Pelvic ultrasonography ...

Diversity of activity participation determines bone mineral content in the lower limbs of pre-pubertal children with developmental coordination disorder.

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Fong, S S M; Vackova, D; Choi, A W M; Cheng, Y T Y; Yam, T T T; Guo, X

2018-04-01

This study examined the relationships between activity participation and bone mineralization in children with developmental coordination disorder. Limited participation in physical, recreational, social, and skill-based and self-improvement activities contributed to lower bone mineral content. For improved bone health, these children should participate in a variety of activities, not only physical activities. Limited activity participation in children with developmental coordination disorder (DCD) may have a negative impact on bone mineral accrual. The objectives of this study were to compare bone mineralization and activity participation patterns of pre-pubertal children with DCD and those with typical development, and to determine the association between activity participation patterns and bone mineralization in children with DCD. Fifty-two children with DCD (mean age = 7.51 years) and 61 children with typical development (mean age = 7.22 years) participated in the study. Appendicular and total body (less head) bone mineral content (BMC) and bone mineral density (BMD) were evaluated by a whole-body dual-energy X-ray absorptiometry scan. Activity participation patterns were assessed using the Children's Assessment of Participation and Enjoyment (CAPE) questionnaire. Children with DCD had lower appendicular and total body BMCs and BMDs than children with typical development overall (p accounting for the effects of age, sex, height, lean mass, and fat mass, the total activity diversity score remained independently associated with leg BMC in children with DCD, explaining 5.1% of the variance (p = 0.030). However, the physical activity diversity score was no longer associated with leg BMC (p = 0.090). Diversity of activity participation and bone mineralization were lower in pre-pubertal children with DCD. Decreased total activity participation diversity was a contributing factor to lower BMC in the legs of children with DCD.

School performance in pubertal adolescents with dysmenorrhea

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Syamsir Alam

2011-08-01

Full Text Available Background Dysmenorrhea is a common gynecological symptom reported in adolescent girls. Prevalence of the condition has been reported to be 45 - 75%. Absenteeism from work and school as a result of dysmenorrhea is common (13 - 51% of women have been absent at least once, and 5 - 14% are often absent due to the severity of symptoms. Objective To compare school performance in pubertal adolescent girls with and without dysmenorrhea. Methods This cross-sectional study was conducted in June 2010 in adolescent females aged 12 - 18 years from the Musthafawiyah School, Mandailing Natal district, North Sumatera. Adolescent females with and without dysmenorrhea were recruited for this study. All participants completed questionnaires including age of menarche, length of menstrual cycle, length of bleeding, number of sanitary napkins used daily and school absences. School reports from two consecutive semesters in one year were used to evaluate subjects’ academic performance. An academic score of higher than 7.5 was considered good performance while scores of less than 7.5 were considered poor. We used the chi-square test to analyze differences in school performance between girls with and without dysmenorrhea. Results One hundred and sixteen participants were divided into 2 groups, those with and without dysmenorrhea, of 58 subjects each. We found no significant difference in school performance between the two groups, P=0.176 (95% CI -0.009 to -0.048 and P=0.08 (95%CI -0.052 to 0.024. Conclusion There was no significant difference in school performance of girls with and without dysmenorrhea.

Associations of Birth Order with Early Adolescent Growth, Pubertal Onset, Blood Pressure and Size: Evidence from Hong Kong's "Children of 1997" Birth Cohort.

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Kwok, Man Ki; Leung, Gabriel M; Schooling, C Mary

2016-01-01

Birth order has been proposed as a cardiovascular risk factor, because the lower birth weight and greater infant weight gain typical of firstborns could programme metabolism detrimentally. We examined the associations of birth order (firstborn or laterborn) with birth weight-for-gestational age, length/height and body mass index (BMI) z-scores during infancy, childhood, and puberty using generalized estimating equations, with age at pubertal onset using interval-censored regression and with age-, sex- and height-standardized blood pressure, height and BMI z-scores at 13 years using linear regression in a population-representative Chinese birth cohort: "Children of 1997" (n = 8,327). Compared with laterborns, firstborns had lower birth weight-for-gestational age (mean difference = -0.18 z-score, 95% confidence interval (CI) -0.23, -0.14), lower infant BMI (-0.09 z-score, 95% CI -0.14, -0.04), greater childhood height (0.10 z-score, 95% CI 0.05, 0.14) and BMI (0.08 z-score, 95% CI 0.03, 0.14), but not greater pubertal BMI (0.05 z-score, 95% CI -0.02, 0.11), adjusted for sex, parental age, birthplace, education and income. Firstborns had earlier onset of pubic hair (time ratio = 0.988, 95% CI 0.980, 0.996), but not breast or genitalia, development. Firstborns had greater BMI (0.07 z-score, 95% CI 0.002, 0.15), but not height (0.05 z-score, 95% CI -0.01, 0.11), at 13 years, but similar blood pressure. Differences by birth order continue into early adolescence with firstborns being heavier with earlier pubic hair development, which could indicate long-term cardiovascular risk.

Associations of Birth Order with Early Adolescent Growth, Pubertal Onset, Blood Pressure and Size: Evidence from Hong Kong's "Children of 1997" Birth Cohort.

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Man Ki Kwok

Full Text Available Birth order has been proposed as a cardiovascular risk factor, because the lower birth weight and greater infant weight gain typical of firstborns could programme metabolism detrimentally.We examined the associations of birth order (firstborn or laterborn with birth weight-for-gestational age, length/height and body mass index (BMI z-scores during infancy, childhood, and puberty using generalized estimating equations, with age at pubertal onset using interval-censored regression and with age-, sex- and height-standardized blood pressure, height and BMI z-scores at 13 years using linear regression in a population-representative Chinese birth cohort: "Children of 1997" (n = 8,327.Compared with laterborns, firstborns had lower birth weight-for-gestational age (mean difference = -0.18 z-score, 95% confidence interval (CI -0.23, -0.14, lower infant BMI (-0.09 z-score, 95% CI -0.14, -0.04, greater childhood height (0.10 z-score, 95% CI 0.05, 0.14 and BMI (0.08 z-score, 95% CI 0.03, 0.14, but not greater pubertal BMI (0.05 z-score, 95% CI -0.02, 0.11, adjusted for sex, parental age, birthplace, education and income. Firstborns had earlier onset of pubic hair (time ratio = 0.988, 95% CI 0.980, 0.996, but not breast or genitalia, development. Firstborns had greater BMI (0.07 z-score, 95% CI 0.002, 0.15, but not height (0.05 z-score, 95% CI -0.01, 0.11, at 13 years, but similar blood pressure.Differences by birth order continue into early adolescence with firstborns being heavier with earlier pubic hair development, which could indicate long-term cardiovascular risk.

Mental Health Problems of Iranian Female Adolescents and Its Association with Pubertal Development: A Nationwide Study

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Aria Sotoudeh

2012-03-01

Full Text Available Mental health problems including emotional and behavioral problems during puberty may be under influence of different risk factors including cultures, living in urban or rural areas and ethnic factors which may vary between different countries. The main aim of this study is to investigate the profile of emotional and behavioral problems and the role of factors such as age, stage of puberty, ethnicity, rurality and living in urban area, as risk factors in Iranian girls. As a part of a large national study we evaluated the emotional and behavioral problems in different stages of puberty in a community sample of Iranian adolescent girls from public schools that were selected by clustered random sampling method. In all subjects, demographic characteristics, and pubertal stages were measured. Emotional and behavioral problems were evaluated using Strength and Difficulties Questionnaire (SDQ. The associations of age, pubertal development indices, socioeconomic and demographic factors with the behavioral problems were assessed. A total number of 4576 students enrolled the study and responded to the questions. The mean age of participants was 13.83 2.19 years. The mean total score of difficulties in participants was 14.34 5.81. According to these results 813 (17.8% adolescents had total problem scores higher than Goodmans cutoff points and the most frequent problem domain was conduct problems (20.5%. According to the results the most related variable with the total difficulty score of SDQ were ethnicity, residency in urban areas and development of menstrual cycle respectively. The results of this study showed that the most correlated factors with mental health problems in Iranian girls during puberty are ethnicity, urbanity and development of menstrual cycle.

Association of Adiposity Genetic Variants With Menarche Timing in 92,105 Women of European Descent

NARCIS (Netherlands)

Fernández-Rhodes, L.; Demerath, E.W.; Cousminer, D.L.; Tao, R.; Dreyfus, J.G.; Esko, T.; Smith, A.V.; Gudnason, V.; Harris, T.B.; Launer, L.; McArdle, P.F.; Yerges-Armstrong, L.M.; Elks, C.E.; Strachan, D.P.; Kutalik, Z.; Vollenweider, P.; Feenstra, B.; Boyd, H.A.; Metspalu, A.; Mihailov, E.; Broer, L.; Zillikens, M.C.; Oostra, B.A.; van Duijn, C.M.; Lunetta, K.L.; Perry, J.R.; Murray, A.; Koller, D.L.; Lai, D.; Corre, T.; Toniolo, D.; Albrecht, E.; Stöckl, D.; Grallert, H.; Gieger, C.; Hayward, C.; Polasek, O.; Rudan, I.; Wilson, J.F.; He, C.; Kraft, P.; Hu, F.B.; Hunter, D.J.; Hottenga, J.J.; Willemsen, G.; Boomsma, D.I.; Byrne, E.M.; Martin, N.G.; Montgomery, G.W.; Warrington, N.M.; Pennell, C.E.; Stolk, L.; Visser, J.A.; Hofman, A.; Uitterlinden, A.G.; Rivadeneira, F.; Lin, P.; Fisher, S.L.; Bierut, L.J.; Crisponi, L.; Porcu, E.; Mangino, M.; Zhai, G.; Spector, T.D.; Buring, J.E.; Rose, L.M.; Ridker, P.M.; Poole, C.; Hirschhorn, J.N.; Murabito, J.M.; Chasman, D.I.; Widén, E.; North, K.E.; Ong, K.K.; Franceschini, N.

2013-01-01

Obesity is of global health concern. There are well-described inverse relationships between female pubertal timing and obesity. Recent genome-wide association studies of age at menarche identified several obesity-related variants. Using data from the ReproGen Consortium, we employed meta-analytical

Fluoride exposure changed the structure and the expressions of HSP related genes in testes of pubertal rats.

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Zhao, Yangfei; Zhao, Jun; Wang, Jinming; Wang, Jundong

2017-10-01

Previous studies have indicated that fluoride exposure damaged the male reproductive function; however, the cellular mechanism of fluoride-induced testicular toxicity is still unclear. In this study, twenty-two female pregnant Wistar rats were allotted randomly to two groups: control (deionized water) and sodium fluoride (NaF, contain F - : 67.86 mg/L) groups. After delivery, the dosage was continued for 15 weeks for puppies. Twelve rats in each group were tested at 6 and 9 (pubertal); 12 and 15 (mature) weeks of age. Our results suggested that organ coefficient of epididymis was significantly decreased in the mature (12 and 15 week-old) rats. Epididymal sperm abnormality and femur fluoride concentration were increased with the concomitant decrease in sperm motility and concentration in these experimental periods. Compared to the control, in the NaF group, the seminiferous tubules of each age were reduced in terms of diameter and thickness. The sperm cells were lost and shedding and finally disappeared after 9 weeks. mRNA and protein levels of HSP27 and 90 were decreased with a concomitant increase in HSP70 and HSF mRNA and protein levels in NaF exposed rats. The mRNA and protein levels of HSP27 and HSF (only mRNA) were significantly increased in NaF treated rats at 9 and 15 weeks of age, respectively. In summary, these results emphasize that NaF induces testicular and sperm abnormalities through the involvement of HSPs especially during the pubertal period. Copyright © 2017 Elsevier Ltd. All rights reserved.

mtDNA copy number in oocytes of different sizes from individual pre- and post-pubertal pigs

DEFF Research Database (Denmark)

Pedersen, Hanne Skovsgaard; Løvendahl, Peter; Larsen, Knud Erik

2014-01-01

from ovaries of 10 pre- and 10 post-pubertal pigs. Cumulus cells were removed and the oocytes were measured (inside-ZP-diameter). Oocytes were transferred to DNAase-free tubes, snap-frozen, and stored at –80°C. The genes ND1 and COX1 were used to determine the mtDNA copy number. Plasmid preparations...... Reproduction 131, 233–245). However, the correlation between size and mtDNA copy number in single oocytes has not been determined. This study describes the relation between oocytes of defined diameters from individual pre- and postpubertal pigs and mtDNA copy number. Cumulus-oocyte complexes were aspirated...

The Examination of the Effectiveness of an Educational Intervention based on the Planned Behavior Theory on Improving Pubertal Health Behavior in Female High School Students

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Farnaz Eslamimehr

2017-09-01

Full Text Available Background: Puberty is a period of psychological, physical, mental, emotional and social growth that stability and development of personality occurs in this period. This study aimed to determine the effect of planned behavior theory on improving pubertal health behavior in female first grade high school students. Materials and Methods:  A quasi-experimental intervention was conducted in female high school in Khamir city, Iran in 2015. One of the schools were randomly assigned to the control group and other to the experimental group. Using the formula sample, 60 students were selected from each school. Samples were evaluated in two stages through pre-test and two months later via post-test by administered questionnaire including questions about demographic characteristics and structures of planned behavior theory. The content of training was presented through lecture group discussion with teaching aids such as booklet and pamphlet. The collected data were analyzed using SPSS version 22. Results: The intervention group mean age at first menstrual period was 12.30 ± 0.84 years old and for control group was 12.25 ± 0.79 years old. The results showed that two months after the intervention, health behaviors, subjective norms, behavioral intention, perceived behavioral control, and attitude, were significantly higher than pre- intervention (P

Effect of the anti-androgenic endocrine disruptor vinclozolin on embryonic testis cord formation and postnatal testis development and function.

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Uzumcu, Mehmet; Suzuki, Hiroetsu; Skinner, Michael K

2004-01-01

Vinclozolin is a systemic dicarboximide fungicide that is used on fruits, vegetables, ornamental plants, and turf grass. Vinclozolin and its metabolites are known to be endocrine disruptors and act as androgen receptor antagonists. The hypothesis tested in the current study is that transient embryonic exposure to an anti-androgenic endocrine disruptor at the time of testis determination alters testis development and subsequently influences adult spermatogenic capacity and male reproduction. The effects of vinclozolin on embryonic testicular cord formation in vitro were examined, as well as the effects of transient in utero vinclozolin exposure on postnatal testis development and function. Embryonic day 13 (E13, sperm-positive vaginal smear day = E0) gonads were cultured in the absence or presence of vinclozolin (50-500microM). Vinclozolin treated gonads had significantly fewer cords (P vinclozolin (100 mg/kg/day) between embryonic days 8 and 14 (E8-E14) of development. Testis morphology and function were analyzed from postnatal day (P) 0, pubertal P20, and adult P60. No significant effect of vinclozolin on testis histology or germ cell viability was observed in P0 testis. The pubertal P20 testis from vinclozolin exposed animals had significantly higher numbers of apoptotic germ cells (P vinclozolin exposed males (P vinclozolin exposed animals was higher in adult P60 animals. Observations demonstrate that vinclozolin can effect embryonic testicular cord formation in vitro and that transient in utero exposure to vinclozolin increases apoptotic germ cell numbers in the testis of pubertal and adult animals. This correlated to reduced sperm motility in the adult. In conclusion, transient exposure to vinclozolin during the time of testis differentiation (i.e. cord formation) alters testis development and function. Observations indicate that transient exposure to an anti-androgenic endocrine disruptor during embryonic development causes delayed effects later in adult life

Pubertal Development and Prepubertal Height and Weight Jointly Predict Young Adult Height and Body Mass Index in a Prospective Study in South Africa.

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Stein, Aryeh D; Lundeen, Elizabeth A; Martorell, Reynaldo; Suchdev, Parminder S; Mehta, Neil K; Richter, Linda M; Norris, Shane A

2016-07-01

Height and adiposity track over childhood, but few studies, to our knowledge, have longitudinally examined the mediating relation of the timing and progression of puberty. We assessed interrelations between prepubertal height and body mass index, the progression through puberty, and young adult height and adiposity. We analyzed data from the Birth to Twenty Plus study (females, n = 823; males, n = 765). Serial measures of anthropometry and pubertal development were obtained between ages 9 and 16 y. We used latent class growth analysis to categorize pubertal development with respect to pubic hair (females and males), breasts (females), and genitalia (males) development. Adult height and weight were obtained at ages 18 to 20 y. Among females, higher latent class (earlier initiation and faster progression through puberty) was associated with an increased risk of obesity [pubic hair class 3 compared with class 1: RR, 3.41 (95% CI: 1.57, 7.44)] and inconsistent associations with height. Among males, higher latent class was associated with increased adult height [pubic hair development class 3 compared with class 1: 2.43 cm (95% CI: 0.88, 4.00)] and increased risk of overweight/obesity [pubic hair development class 3 compared with class 1: OR, 3.44 (95% CI: 1.44, 8.20)]. In females, the association with adult height became inverse after adjusting for prepubertal height [pubic hair development class 3 compared with class 1: females, -1.31 cm (95% CI: -2.32, -0.31)]; in males, the association with height was attenuated with this adjustment [-0.56 cm (95% CI: -1.63, 0.52)]. Associations with adiposity were attenuated after adjusting for prepubertal adiposity. Progression through puberty modifies the relation between prepubertal and adult anthropometry. Screening for early or rapid progression of puberty might identify children at an increased risk of becoming overweight or obese adults.

The importance of puberty for adolescent development: conceptualization and measurement.

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Berenbaum, Sheri A; Beltz, Adriene M; Corley, Robin

2015-01-01

How and why are teenagers different from children and adults? A key question concerns the ways in which pubertal development shapes psychological changes in adolescence directly through changes to the brain and indirectly through the social environment. Empirical work linking pubertal development to adolescent psychological function draws from several different perspectives, often with varying approaches and a focus on different outcomes and mechanisms. The main themes concern effects of atypical pubertal timing on behavior problems during adolescence, effects of pubertal status (and associated hormones) on normative changes in behaviors that can facilitate or hinder development (especially risk-taking, social reorientation, and stress responsivity), and the role of puberty in triggering psychopathology in vulnerable individuals. There is also interest in understanding the ways in which changes in the brain reflect pubertal processes and underlie psychological development in adolescence. In this chapter, we consider the ways that puberty might affect adolescent psychological development, and why this is of importance to developmentalists. We describe the processes of pubertal development; summarize what is known about pubertal influences on adolescent development; consider the assumptions that underlie most work and the methodological issues that affect the interpretation of results; and propose research directions to help understand paths from puberty to behavior. Throughout, we emphasize the importance of pubertal change in all aspects of psychological development, and the ways in which puberty represents an opportunity to study the interplay of biological and social influences. © 2015 Elsevier Inc. All rights reserved.

Endocrine and molecular investigations in a cohort of 25 adolescent males with prominent/persistent pubertal gynecomastia.

Science.gov (United States)

Paris, F; Gaspari, L; Mbou, F; Philibert, P; Audran, F; Morel, Y; Biason-Lauber, A; Sultan, C

2016-03-01

Pubertal gynecomastia is a common condition observed in up to 65% of adolescent males. It is usually idiopathic and tends to regress within 1-2 years. In this descriptive cross-sectional study, we investigated 25 adolescent males with prominent (>B3) and/or persistent (>2 years) pubertal gynecomastia (P/PPG) to determine whether a hormonal/genetic defect might underline this condition. Endocrine investigation revealed the absence of hormonal disturbance for 18 boys (72%). Three patients presented Klinefelter syndrome and three a partial androgen insensitivity syndrome (PAIS) as a result of p.Ala646Asp and p.Ala45Gly mutations of the androgen receptor gene. The last patient showed a 17α-hydroxylase/17,20-lyase deficiency as a result of a compound heterozygous mutation of the CYP17A1 gene leading to p.Pro35Thr(P35T) and p.Arg239Stop(R239X) in the P450c17 protein. Enzymatic activity was analyzed: the mutant protein bearing the premature stop codon R239X showed a complete loss of 17α-hydroxylase and 17,20-lyase activity. The mutant P35T seemed to retain 15-20% of 17α-hydroxylase and about 8-10% of 17,20-lyase activity. This work demonstrates that P/PPG had an endocrine/genetic cause in 28% of our cases. PAIS may be expressed only by isolated gynecomastia as well as by 17α-hydroxylase/17,20-lyase deficiency. Isolated P/PPG is not always a 'physiological' condition and should thus be investigated through adequate endocrine and genetic investigations, even though larger studies are needed to better determine the real prevalence of genetic defects in such patients. © 2016 American Society of Andrology and European Academy of Andrology.

The Interplay between Gaze Following, Emotion Recognition, and Empathy across Adolescence; a Pubertal Dip in Performance?

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Rianne van Rooijen

2018-02-01

Full Text Available During puberty a dip in face recognition is often observed, possibly caused by heightened levels of gonadal hormones which in turn affects the re-organization of relevant cortical circuitry. In the current study we investigated whether a pubertal dip could be observed in three other abilities related to social information processing: gaze following, emotion recognition from the eyes, and empathizing abilities. Across these abilities we further explored whether these measurements revealed sex differences as another way to understand how gonadal hormones affect processing of social information. Results show that across adolescence, there are improvements in emotion recognition from the eyes and in empathizing abilities. These improvements did not show a dip, but are more plateau-like. The gaze cueing effect did not change over adolescence. We only observed sex differences in empathizing abilities, with girls showing higher scores than boys. Based on these results it appears that gonadal hormones are not exerting a unified influence on higher levels of social information processing. Further research should also explore changes in (visual information processing around puberty onset to find a more fitted explanation for changes in social behavior across adolescence.

Excessive Refined Carbohydrates and Scarce Micronutrients Intakes Increase Inflammatory Mediators and Insulin Resistance in Prepubertal and Pubertal Obese Children Independently of Obesity

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Mardia López-Alarcón

2014-01-01

Full Text Available Background. Low-grade inflammation is the link between obesity and insulin resistance. Because physiologic insulin resistance occurs at puberty, obese pubertal children are at higher risk for insulin resistance. Excessive diets in refined carbohydrates and saturated fats are risk factors for insulin resistance, but calcium, magnesium, vitamin-D, and the omega-3 fatty acids likely protect against inflammation and insulin resistance. Objective. To analyze interactions among dietary saturated fat, refined carbohydrates, calcium, magnesium, vitamin D, and omega-3 fatty acids on the risk of inflammation and insulin resistance in a sample of prepubertal and pubertal children. Methods. A sample of 229 children from Mexico City was analyzed in a cross-sectional design. Anthropometric measurements, 24 h recall questionnaires, and blood samples were obtained. Serum insulin, glucose, calcium, magnesium, 25-OHD3, C-reactive protein, leptin, adiponectin, and erythrocytes fatty acids were measured. Parametric and nonparametric statistics were used for analysis. Results. While mean macronutrients intake was excessive, micronutrients intake was deficient (P<0.01. Inflammation determinants were central obesity and magnesium-deficient diets. Determinants of insulin resistance were carbohydrates intake and circulating magnesium and adiponectin. Conclusions. Magnesium-deficient diets are determinants of inflammation, while high intake of refined carbohydrates is a risk factor for insulin resistance, independently of central adiposity.

Functional state of reproductive system in pubertal girls having autoimmune thyroiditis

International Nuclear Information System (INIS)

Leonova, T.A.

2003-01-01

Purpose of the present work is to study the condition of reproductive system in pubertal girls with autoimmune thyroiditis (AT), exposed to radiation as a result of the Chernobyl accident, and to study various clinical symptoms of AT in relation to peculiarities of natural course of the disease, age and absorbed thyroid dose. We performed complex clinical investigation of 225 girls from Belarus with AT aged 11-16. We revealed, that girls with AT irradiated at the age of 0-3 had significant changes in gonadotrophic hormones levels in blood serum in lutein phase at the age of 13-14 in comparison with control groups. In spite of the fact that mainly the meaning investigated hormones were in the range of age norm, at the age of 15-16 among girls being irradiated greater percent of increased meaning of factor LG/FSG is revealed. Girls with AT had symptoms of dysfunction in sensitivity of target organs (ovaries and uterus) receptors. At the age of 15-16 among girls with AT, exposed to radiation, direct dependencies are established between the level of absorbed thyroid doze and meaning of LG and prolactin

Childhood body mass index at 5.5 years mediates the effect of prenatal maternal stress on daughters' age at menarche: Project Ice Storm.

Science.gov (United States)

Duchesne, A; Liu, A; Jones, S L; Laplante, D P; King, S

2017-04-01

Early pubertal timing is known to put women at greater risk for adverse physiological and psychological health outcomes. Of the factors that influence girls' pubertal timing, stress experienced during childhood has been found to advance age at menarche (AAM). However, it is not known if stress experienced by mothers during or in the months before conception can be similarly associated with earlier pubertal timing. Prenatal maternal stress (PNMS) is associated with metabolic changes, such as increased childhood adiposity and risk of obesity, that have been associated with earlier menarchal age. Using a prospective longitudinal design, the present study tested whether PNMS induced by a natural disaster is either directly associated with earlier AAM, or whether there is an indirect association mediated through increased girls' body mass index (BMI) during childhood. A total of 31 girls, whose mothers were exposed to the Quebec's January 1998 ice storm during pregnancy were followed from 6 months to 5 1/2 to 5.5 years of age. Mother's stress was measured within 6 months of the storm. BMI was measured at 5.5 years, and AAM was assessed through teen's self-report at 13.5 and 15.5 years of age. Results revealed that greater BMI at 5.5 years mediated the effect of PNMS on decreasing AAM [B=-0.059, 95% confidence intervals (-0.18, -0.0035)]. The present study is the first to demonstrate that maternal experience of stressful conditions during pregnancy reduces AAM in the offspring through its effects on childhood BMI. Future research should consider the impact of AAM on other measures of reproductive ability.

Pubertal development and fertility in survivors of childhood acute myeloid leukemia treated with chemotherapy only: a NOPHO-AML study.

Science.gov (United States)

Molgaard-Hansen, Lene; Skou, Anne-Sofie; Juul, Anders; Glosli, Heidi; Jahnukainen, Kirsi; Jarfelt, Marianne; Jónmundsson, Guðmundur K; Malmros, Johan; Nysom, Karsten; Hasle, Henrik

2013-12-01

More than 60% of children with acute myeloid leukemia (AML) become long-term survivors. Most are cured using chemotherapy without hematopoietic stem cell transplantation (HSCT). We report on pubertal development and compare self-reported parenthood among AML survivors and their siblings. We included 137 children treated for AML according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO)-AML-84, -88, and -93 trials, who were alive by June 2007. Patients with relapse or treated with HSCT were excluded. AML survivors participated in a physical and biochemical examination (n = 102) and completed a questionnaire (n = 101). One of their siblings completed an identical questionnaire (n = 84). At a median follow-up of 11 years (range 5-25) after diagnosis of AML the survivors (median age 16 years, range 5-36) were either prepubertal or had entered puberty normally. Serum levels of FSH, LH, testosterone, estradiol, sex hormone binding globulin (SHBG), inhibin A and B, and testicular volumes were within normal ranges. Anti-Müllerian hormone (AMH) levels were decreased in 5 of 40 postpubertal females. Mean reported age at menarche was 13.1 (range 11-17) years. Among survivors 15 years of age or older 31% of females reported pregnancies and 9% of males reported pregnancies in their partners, rates comparable with the frequency reported by their siblings. Most AML survivors treated with chemotherapy had normal pubertal development and fertility, however, AMH levels were decreased in 13% of postpubertal females. Longer follow-up is necessary to evaluate possible risk of premature ovarian failure. © 2013 Wiley Periodicals, Inc.

Correlates of adolescent sleep time and variability in sleep time: the role of individual and health related characteristics.

Science.gov (United States)

Moore, Melisa; Kirchner, H Lester; Drotar, Dennis; Johnson, Nathan; Rosen, Carol; Redline, Susan

2011-03-01

Adolescents are predisposed to short sleep duration and irregular sleep patterns due to certain host characteristics (e.g., age, pubertal status, gender, ethnicity, socioeconomic class, and neighborhood distress) and health-related variables (e.g., ADHD, asthma, birth weight, and BMI). The aim of the current study was to investigate the relationship between such variables and actigraphic measures of sleep duration and variability. Cross-sectional study of 247 adolescents (48.5% female, 54.3% ethnic minority, mean age of 13.7years) involved in a larger community-based cohort study. Significant univariate predictors of sleep duration included gender, minority ethnicity, neighborhood distress, parent income, and BMI. In multivariate models, gender, minority status, and BMI were significantly associated with sleep duration (all pminority adolescents, and those of a lower BMI obtaining more sleep. Univariate models demonstrated that age, minority ethnicity, neighborhood distress, parent education, parent income, pubertal status, and BMI were significantly related to variability in total sleep time. In the multivariate model, age, minority status, and BMI were significantly related to variability in total sleep time (all pminority adolescents, and those of a lower BMI obtaining more regular sleep. These data show differences in sleep patterns in population sub-groups of adolescents which may be important in understanding pediatric health risk profiles. Sub-groups that may particularly benefit from interventions aimed at improving sleep patterns include boys, overweight, and minority adolescents. Copyright © 2011 Elsevier B.V. All rights reserved.

Sex, age, pubertal development and use of oral contraceptives in relation to serum concentrations of DHEA, DHEAS, 17α-hydroxyprogesterone, Δ4-androstenedione, testosterone and their ratios in children, adolescents and young adults

DEFF Research Database (Denmark)

Søeborg, Tue; Frederiksen, Hanne; Mouritsen, Annette

2014-01-01

The influence of sex, age, pubertal development and oral contraceptives on dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), testosterone (T), calculated free testosterone (fT), free androgen index (FAI) and selected ratios in 1798...... serum samples from healthy children, adolescents and young adults was evaluated. Samples were analyzed by Turboflow-LC-MS/MS. Sex hormone-binding globulin was analyzed by immunoassay. All steroid metabolite concentrations were positively associated with age and pubertal development in both sexes....... Use of oral contraceptives significantly lowered serum concentrations of all steroid metabolites, fT, FAI, the 17-OHP/Adione, the Adione/T and the DHEA/Adione ratios, but not the DHEA/DHEAS ratio. We provide reference ranges for DHEA, DHEAS, 17-OHP, Adione, T, fT, FAI and selected ratios in relation...

Ovarian function following pelvic irradiation in prepubertal and pubertal girls and young adult women

Energy Technology Data Exchange (ETDEWEB)

Schuck, A.; Hamelmann, V. [University Hospital Muenster (Germany). Dept. of Radiotherapy; Braemswig, J.H. [University Hospital Muenster (DE). Dept. of Pediatrics] [and others

2005-08-01

Purpose: To analyze the effect of pelvic radiotherapy on ovarian function in prepubertal and pubertal girls and young adult women. Patients and methods: In a retrospective monoinstitutional analysis, patients <30 years of age at diagnosis were included who had been irradiated between 1979 and 1998. The main tumor types were Hodgkin's disease (38%), Erwing's sarcoma (20%) and nephroblastoma (11%). Patients were classified into three groups according to the position of the ovary in relation to the radiation portals. Group 1 was defined by direct irradiation of both ovaries. Group 2 patients were included with both ovaries potentially located in the radiation portals. In group 3, at least one ovary was not directly irradiated. The median follow-up was 128 months. Results: 16 of 55 analyzed patients were categorized in group 1. In ten of these patients, hormone status was evaluable. The ovarian doses were {>=}15 Gy. Except for one patient treated with 15 Gy all developed hormone failure. Eight of 14 patients of group 2 were evaluable. Seven of these patients developed ovarian failure. 19 of 24 patients in group 3 were evaluable. Nine of these patients developed ovarian failure. The observed difference in the rate of ovarian failure between the groups is statistifcally significant (p=0.045). Conclusion: All patients receiving >15 Gy to the ovaries developed hormone failure. In one case of a patient receiving an ovarian dose of 15 Gy, hormone failure was not found. In case of pelvic irradiation excluding at least one ovary, approximately half of the patients developed ovarian dysfunction, probably also due to the effects of polychemotherapy. (orig.)

Associations of Birth Order with Early Adolescent Growth, Pubertal Onset, Blood Pressure and Size: Evidence from Hong Kong?s ?Children of 1997? Birth Cohort

OpenAIRE

Kwok, Man Ki; Leung, Gabriel M.; Schooling, C. Mary

2016-01-01

Background Birth order has been proposed as a cardiovascular risk factor, because the lower birth weight and greater infant weight gain typical of firstborns could programme metabolism detrimentally. Methods We examined the associations of birth order (firstborn or laterborn) with birth weight-for-gestational age, length/height and body mass index (BMI) z-scores during infancy, childhood, and puberty using generalized estimating equations, with age at pubertal onset using interval-censored re...

The effects of out-of-school time on changes in youth risk of obesity across the adolescent years.

Science.gov (United States)

Zarrett, Nicole; Bell, Bethany A

2014-01-01

This study examined the longitudinal effects of out-of-school time (OST) activities on youth weight-status through mid-to-late adolescence. First, using pattern-centered methods, we identified the prominent ways in which youth allocate their OST across 12 common active and sedentary activities available to them. Second, through multi-level modeling procedures we examined the relation of OST activity patterns to: 1) BMI-status during the 11th grade, and; 2) within-person change in BMI-status across the adolescent years. After accounting for race, gender, SES, pubertal-status, and gaming, youth who participated in a sports-dominant activity pattern for 2 or more years had significantly lower 11th grade odds of being at-risk for overweight/obesity compared to youth in all other activity patterns. Youth of all other activity patterns had similar odds of being at-risk as Low-Activity youth and each other. Understanding the relations of OST to youth healthy weight is a critical first step in developing healthy OST settings. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Diurnal and seasonal cortisol, testosterone, and DHEA rhythms in boys and girls during puberty.

Science.gov (United States)

Matchock, Robert L; Dorn, Lorah D; Susman, Elizabeth J

2007-01-01

Diurnal and seasonal rhythms of cortisol, testosterone, and DHEA were examined, as little is known about the relationship between these rhythmicities and pubertal development. Salivary samples were obtained from 60 boys and 60 girls at approximately 07:45, 08:00, 08:30, 12:00, 16:50, and 21:00 h. The participants' ages ranged from 8-14 yrs, and each participant was tested three times at six-month intervals. The study was conducted at a General Clinical Research Center (GCRC) and at the homes of the participants. All hormones showed diurnal fluctuations. The acrophase (peak time) of cortisol occurred earlier than for testosterone or DHEA and showed a seasonal effect, with the acrophase occurring earlier in spring than in summer. The cortisol acrophase also occurred later in the day for boys than for girls during later puberty. Seasonal effects were found only for cortisol with higher concentrations in the spring and summer. Cortisol concentrations were relatively stable across pubertal maturation, but significantly lower concentrations were observed at pubertal stage 3 compared to the other stages. Morning cortisol levels were also higher in boys at pubertal stage 2. Testosterone concentrations were higher in boys at pubertal stages 3 and 4, and DHEA was lower at pubertal stage 1 than 3 and 4 for both boys and girls. For the total sample, there was a positive correlation between DHEA and testosterone during early puberty (stages 1-3) but not later puberty (stages 4-5). Awakening secretory activity correlated with daytime secretory activity for testosterone and DHEA, but not for cortisol. These data provide novel chronobiological information on cortisol, testosterone, and DHEA as it relates to sexual maturation and encourage further study on both normal and abnormal endocrine rhythms.

Does Competence Mediate the Associations between Puberty and Internalizing or Externalizing Problems in Adolescent Girls

Science.gov (United States)

Negriff, Sonya; Hillman, Jennifer, B.; Dorn, Lorah D.

2011-01-01

Purpose To examine separate mediational models linking a) menarcheal status or b) pubertal timing to internalizing and externalizing problems through competence. Method Cross-sectional analyses of 262 adolescent girls (11–17 years; M=14.93, SD=2.17) enrolled in a longitudinal study examining the association of psychological functioning and smoking with reproductive and bone health. Measures of menarcheal status (pre/post), pubertal timing (early, on-time, or late), internalizing and externalizing behavior, and perceived competence (parent and adolescent report) were obtained. Structural Equation Modeling was used for analyses. Results Perceived competence was found to fully mediate the association between menarcheal status and parent report of internalizing and externalizing problems. For adolescent report, there was a full mediation effect for internalizing problems but a partial mediation effect for externalizing problems. Being menarcheal was related to lower competence which was related to higher internalizing and externalizing problems. Models including pubertal timing were not significant. Conclusions Perceived competence is important in understanding the associations between menarcheal status and internalizing and externalizing problems. Interventions targeting competence, particularly in post-menarcheal girls, may reduce or prevent problem behaviors. PMID:21939864

Contribution of the Endocrine Perspective in the Evaluation of Endocrine Disrupting Chemical Effects

DEFF Research Database (Denmark)

Bourguignon, Jean-Pierre; Juul, Anders; Franssen, Delphine

2016-01-01

Debate makes science progress. In the field of endocrine disruption, endocrinology has brought up findings that substantiate a specific perspective on the definition of endocrine disrupting chemicals (EDCs), the role of the endocrine system and the endpoints of hormone and EDC actions among other...... issues. This paper aims at discussing the relevance of the endocrine perspective with regard to EDC effects on pubertal timing. Puberty involves particular sensitivity to environmental conditions. Reports about the advancing onset of puberty in several countries have led to the hypothesis...

The significant effects of puberty on the genetic diathesis of binge eating in girls.

Science.gov (United States)

Klump, Kelly L; Culbert, Kristen M; O'Connor, Shannon; Fowler, Natasha; Burt, S Alexandra

2017-08-01

Recent data show significant phenotypic and genetic associations between ovarian hormones and binge eating in adulthood. Theories of hormonal risk focus on puberty and the possibility that hormone activation induces changes in genetic effects that then lead to differential risk for binge eating in postpuberty and adulthood. Although this theory is difficult to test in humans, an indirect test is to examine whether genetic influences on binge eating increase during the pubertal period in girls. Prior work has shown pubertal increases in genetic influences on overall disordered eating symptoms, but no study to date has examined binge eating. The present study was the first to examine these increases for binge eating. Participants included 1,568 female twins (aged 8-25 years) from the Michigan State University Twin Registry. Binge eating and pubertal development were assessed with self-report questionnaires. Twin moderation models showed significant linear increases in genetic effects from prepuberty (5%) to postpuberty (42%), even after controlling for the effects of age and body mass index. Results provide critical support for increased genetic influences on binge eating during puberty. Additional studies are needed to identify hormonal mechanisms and fully test contemporary models of ovarian hormone risk. © 2017 Wiley Periodicals, Inc.

Puberty as a Critical Risk Period for Eating Disorders: A Review of Human and Animal Studies

Science.gov (United States)

Klump, Kelly L.

2013-01-01

Puberty is one of the most frequently discussed risk periods for the development of eating disorders. Prevailing theories propose environmentally mediated sources of risk arising from the psychosocial effects (e.g., increased body dissatisfaction, decreased self-esteem) of pubertal development in girls. However, recent research highlights the potential role of ovarian hormones in phenotypic and genetic risk for eating disorders during puberty. The goal of this paper is to review data from human and animal studies in support of puberty as a critical risk period for eating disorders and evaluate the evidence for hormonal contributions. Data are consistent in suggesting that both pubertal status and pubertal timing significantly impact risk for most eating disorders in girls, such that advanced pubertal development and early pubertal timing are associated with increased rates of eating disorders and their symptoms in both cross-sectional and longitudinal research. Findings in boys have been much less consistent and suggest a smaller role for puberty in risk for eating disorders in boys. Twin and animal studies indicate that at least part of the female-specific risk is due to genetic factors associated with estrogen activation at puberty. In conclusion, data thus far support a role for puberty in risk for eating disorders and highlight the need for additional human and animal studies of hormonal and genetic risk for eating disorders during puberty. PMID:23998681

IGF-1 has sexually dimorphic, pleiotropic, and time-dependent effects on healthspan, pathology, and lifespan.

Science.gov (United States)

Ashpole, Nicole M; Logan, Sreemathi; Yabluchanskiy, Andriy; Mitschelen, Matthew C; Yan, Han; Farley, Julie A; Hodges, Erik L; Ungvari, Zoltan; Csiszar, Anna; Chen, Sixia; Georgescu, Constantin; Hubbard, Gene B; Ikeno, Yuji; Sonntag, William E

2017-04-01

Reduced circulating levels of IGF-1 have been proposed as a conserved anti-aging mechanism that contributes to increased lifespan in diverse experimental models. However, IGF-1 has also been shown to be essential for normal development and the maintenance of tissue function late into the lifespan. These disparate findings suggest that IGF-1 may be a pleiotropic modulator of health and aging, as reductions in IGF-1 may be beneficial for one aspect of aging, but detrimental for another. We postulated that the effects of IGF-1 on tissue health and function in advanced age are dependent on the tissue, the sex of the animal, and the age at which IGF-1 is manipulated. In this study, we examined how alterations in IGF-1 levels at multiple stages of development and aging influence overall lifespan, healthspan, and pathology. Specifically, we investigated the effects of perinatal, post-pubertal, and late-adult onset IGF-1 deficiency using genetic and viral approaches in both male and female igf f/f C57Bl/6 mice. Our results support the concept that IGF-1 levels early during lifespan establish the conditions necessary for subsequent healthspan and pathological changes that contribute to aging. Nevertheless, these changes are specific for each sex and tissue. Importantly, late-life IGF-1 deficiency (a time point relevant for human studies) reduces cancer risk but does not increase lifespan. Overall, our results indicate that the levels of IGF-1 during development influence late-life pathology, suggesting that IGF-1 is a developmental driver of healthspan, pathology, and lifespan.

Sex Differences in Binge Eating: Gonadal Hormone Effects Across Development.

Science.gov (United States)

Klump, Kelly L; Culbert, Kristen M; Sisk, Cheryl L

2017-05-08

Eating disorders are highly sexually differentiated disorders that exhibit a female predominance in risk. Most theories focus on psychosocial explanations to the exclusion of biological/genetic influences. The purpose of this descriptive review is to evaluate evidence from animal and human studies in support of gonadal hormone effects on sex differences in binge eating. Although research is in its nascent stages, findings suggest that increased prenatal testosterone exposure in males appears to protect against binge eating. Although pubertal testosterone may exert additional protective effects, the prenatal period is likely critical for the decreased risk observed in males. By contrast, studies indicate that, in females, it is the lack of prenatal testosterone coupled with the organizational effects of pubertal ovarian hormones that may lead to increased binge eating. Finally, twin data suggest that changes in genetic risk may underlie these hormone influences on sex differences across development.

The effect of puberty on fat oxidation rates during exercise in overweight and normal-weight girls.

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Chu, L; Riddell, M C; Schneiderman, J E; McCrindle, B W; Hamilton, J K

2014-01-01

Excess weight is often associated with insulin resistance (IR) and may disrupt fat oxidation during exercise. This effect is further modified by puberty. While studies have shown that maximal fat oxidation rates (FOR) during exercise decrease with puberty in normal-weight (NW) and overweight (OW) boys, the effect of puberty in NW and OW girls is unclear. Thirty-three NW and OW girls ages 8-18 yr old completed a peak aerobic capacity test on a cycle ergometer. FOR were calculated during progressive submaximal exercise. Body composition and Tanner stage were determined. For each participant, a best-fit polynomial curve was constructed using fat oxidation vs. exercise intensity to estimate max FOR. In a subset of the girls, IR derived from an oral glucose tolerance test (n = 20), and leptin and adiponectin levels (n = 11) were assessed in relation to FOR. NW pre-early pubertal girls had higher max FOR [6.9 ± 1.4 mg·kg fat free mass (FFM)(-1)·min(-1)] than NW mid-late pubertal girls (2.2 ± 0.9 mg·kg FFM(-1)·min(-1)) (P = 0.002), OW pre-early pubertal girls (3.8 ± 2.1 mg·kg FFM(-1)·min(-1)), and OW mid-late pubertal girls (3.3 ± 0.9 mg·kg FFM(-1)·min(-1)) (P puberty; however, this decrease associated with puberty was blunted in OW girls due to lower FOR in pre-early puberty. The presence of IR due to obesity potentially masks the effect of puberty on FOR during exercise in girls.

Ethanolic extract of Moringa oleifera Lam. leaves protect the pre-pubertal spermatogonial cells from cyclophosphamide-induced damage.

Science.gov (United States)

Nayak, Guruprasad; Honguntikar, Sachin D; Kalthur, Sneha Guruprasad; D'Souza, Antony Sylvan; Mutalik, Srinivas; Setty, Manjunath M; Kalyankumar, Raksha; Krishnamurthy, Hanumanthappa; Kalthur, Guruprasad; Adiga, Satish Kumar

2016-04-22

Moringa oleifera Lam. is widely cultivated in Asian and African countries for its medicinal and dietary significance. The leaves are highly nutritious and are known to possess various biological activities. Pre-pubertal Swiss albino male mice were injected with single dose of cyclophosphamide (CP, 200mg/kg body weight) or ethanolic extract of Moringa oleifera leaves (MOE, 100mg/kg body weight) intraperitoneally. In combination group, MOE was administered 24h prior to CP injection. CP induced a significant decrease in testicular weight (p<0.01) and depletion of germ cells (p<0.001) and higher level of DNA damage (p<0.001) compared to control. The expression of P53, Bax, Cytochrome C (Cyt C) was increased while there was a decrease in the expression of Bcl2, c-Kit and Oct4. Administration of MOE 24h prior to CP treatment ameliorated the depletion (p<0.001), DNA damage (p<0.001) and apoptosis (p<0.01) of germ cells induced by CP. The mitigating effect of MOE appears to be mediated by up-regulating the expression of c-Kit and Oct4 transcripts in P53-independent manner. MOE protects the spermatogonial cells from CP-induced damage by modulating the apoptotic response elicited by CP and therefore can be considered as an efficient method of male fertility preservation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk

DEFF Research Database (Denmark)

Day, Felix R; Thompson, Deborah J; Helgason, Hannes

2017-01-01

The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project-imputed genotype data in up to ∼370,000 women, we identify 389 independent signals (P ... pubertal development. In Icelandic data, these signals explain ∼7.4% of the population variance in age at menarche, corresponding to ∼25% of the estimated heritability. We implicate ∼250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare...... variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women...

Pedometer assessed physical activity in urban pubertal children: first report from India.

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Contractor, Aashish; Bhanushali, Aparna; Changrani, Jyotsna; Angadia, Siddharth; Das, Bibhu R

2014-11-01

Inadequate physical activity is a risk factor for several lifestyle diseases. In the current study we have tried to evaluate the physical activity levels in urban Indian pubertal children as well as investigate the relationship between step counts and body composition. A total of 1032 children aged 12 to 15 years wore pedometers for 2 weekdays and 2 weekend days, the final cohort included 910 subjects with 467 boys and 443 girls. Mean weekday steps were 11,062 ± 4741 for boys and 9619 ± 4144 for girls; weekend steps were 10,842 ± 5034 for boys and 9146 ± 5159 for girls, which were both significantly different. The weekend steps were consistently lower in both genders. Analysis of children not meeting a cut-off of 10,000 steps indicated that 45% of the boys aged 12; 54% aged 13; 43% to 48% aged 14 and 50% in the aged 15 did not meet the cut-off. In girls higher levels of inactivity were seen with 58% to 65% aged 12; 69% to 73% aged 13; 49% to 58% aged 14 and 50% to 100% in age-group 15 did not meet the cut-off on weekdays and weekends respectively. The high level of physical inactivity in the representative urban Indian children is a cause of grave concern and necessitates urgent intervention strategies to be formulated.

The timing of normal puberty and the age limits of sexual precocity

DEFF Research Database (Denmark)

Parent, Anne-Simone; Teilmann, Grete; Juul, Anders

2003-01-01

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western European...... the environment has been considered. These observations urge further study of the onset of puberty as a possible sensitive and early marker of the interactions between environmental conditions and genetic susceptibility that can influence physiological and pathological processes....

Long-term skeletal and dental effects and treatment timing for functional appliances in Class II malocclusion.

Science.gov (United States)

Franchi, Lorenzo; Pavoni, Chiara; Faltin, Kurt; McNamara, James A; Cozza, Paola

2013-03-01

To analyze the long-term skeletal and dentoalveolar effects and to evaluate treatment timing of Class II treatment with functional appliances followed by fixed appliances. A group of 40 patients (22 females and 18 males) with Class II malocclusion consecutively treated either with a Bionator or an Activator followed by fixed appliances was compared with a control group of 20 subjects (9 females and 11 males) with untreated Class II malocclusion. Lateral cephalograms were available at the start of treatment (mean age 10 years), end of treatment with functional appliances (mean age 12 years), and long-term observation (mean age 18.6 years). The treated sample also was divided into two groups according to skeletal maturity. The early-treatment group was composed of 20 subjects (12 females and 8 males) treated before puberty, while the late-treatment group included 20 subjects (10 females and 10 males) treated at puberty. Statistical comparisons were performed with analysis of variance followed by Tukey's post hoc tests. Significant long-term mandibular changes (Co-Gn) in the treated group (3.6 mm over the controls) were associated with improvements in the skeletal sagittal intermaxillary relationship, overjet, and molar relationship (∼3.0-3.5 mm). Treatment during the pubertal peak was able to produce significantly greater increases in total mandibular length (4.3 mm) and mandibular ramus height (3.1 mm) associated with a significant advancement of the bony chin (3.9 mm) when compared with treatment before puberty. Treatment of Class II malocclusion with functional appliances appears to be more effective at puberty.

Secular trends of growth and pubertal maturation of school children in Southern Thailand.

Science.gov (United States)

Jaruratanasirikul, Somchit; Sriplung, Hutcha

2015-01-01

In Thailand, studies of growth date back to 1975, but there have been no studies examining any trends in increasing/decreasing growth. To determine if there have been any secular trends of increasing/decreasing growth and/or ages at puberty in Thai children. In 2012, a cross-sectional study of growth was conducted in 3460 children. The median heights and weights and the ages of pubertal maturation were compared with previous studies. Correlations between the secular trends and the health statistics indicators were calculated. From 1975-2012, the median final height of boys and girls had increased by 1.32 and 0.86 cm/decade and weight by 2.49 and 1.76 kg/decade, respectively. In girls, the age at thelarche and menarche had declined by 0.39 and 0.12 years/decade, respectively. In boys, the age at testicular enlargement Tanner II had declined by 0.15 years/decade. Increased physical growth was positively correlated to life expectancy, per capita income and prevalence of overweight/obesity was negatively correlated to prevalence of malnutrition and under-five mortality rate. The positive secular trend towards an increase in growth and a decline in the age at onset of puberty of Thai children is correlated with improvements in overall living conditions in Thailand.

Genetic factors modulate the impact of pubertal androgen excess on insulin sensitivity and fertility.

Directory of Open Access Journals (Sweden)

Abigail R Dowling

Full Text Available Polycystic ovary syndrome (PCOS is the most common endocrine disorder of reproductive age women. The syndrome is caused by a combination of environmental influences and genetic predisposition. Despite extensive efforts, the heritable factors contributing to PCOS development are not fully understood. The objective of this study was to test the hypothesis that genetic background contributes to the development of a PCOS-like reproductive and metabolic phenotype in mice exposed to excess DHEA during the pubertal transition. We tested whether the PCOS phenotype would be more pronounced on the diabetes-prone C57BL/6 background than the previously used strain, BALB/cByJ. In addition, we examined strain-dependent upregulation of the expression of ovarian and extra-ovarian candidate genes implicated in human PCOS, genes containing known strain variants, and genes involved with steroidogenesis or insulin sensitivity. These studies show that there are significant strain-related differences in metabolic response to excess androgen exposure during puberty. Additionally, our results suggest the C57BL/6J strain provides a more robust and uniform experimental platform for PCOS research than the BALB/cByJ strain.

Genetic factors modulate the impact of pubertal androgen excess on insulin sensitivity and fertility.

Science.gov (United States)

Dowling, Abigail R; Nedorezov, Laura B; Qiu, Xiaoliang; Marino, Joseph S; Hill, Jennifer W

2013-01-01

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of reproductive age women. The syndrome is caused by a combination of environmental influences and genetic predisposition. Despite extensive efforts, the heritable factors contributing to PCOS development are not fully understood. The objective of this study was to test the hypothesis that genetic background contributes to the development of a PCOS-like reproductive and metabolic phenotype in mice exposed to excess DHEA during the pubertal transition. We tested whether the PCOS phenotype would be more pronounced on the diabetes-prone C57BL/6 background than the previously used strain, BALB/cByJ. In addition, we examined strain-dependent upregulation of the expression of ovarian and extra-ovarian candidate genes implicated in human PCOS, genes containing known strain variants, and genes involved with steroidogenesis or insulin sensitivity. These studies show that there are significant strain-related differences in metabolic response to excess androgen exposure during puberty. Additionally, our results suggest the C57BL/6J strain provides a more robust and uniform experimental platform for PCOS research than the BALB/cByJ strain.

Growth hormone mediates pubertal skeletal development independent of hepatic IGF-1 production.

Science.gov (United States)

Courtland, Hayden-William; Sun, Hui; Beth-On, Mordechay; Wu, Yingjie; Elis, Sebastien; Rosen, Clifford J; Yakar, Shoshana

2011-04-01

Deficiencies in either growth hormone (GH) or insulin-like growth factor 1 (IGF-1) are associated with reductions in bone size during growth in humans and animal models. Liver-specific IGF-1-deficient (LID) mice, which have 75% reductions in serum IGF-1, were created previously to separate the effects of endocrine (serum) IGF-1 from autocrine/paracrine IGF-1. However, LID mice also have two- to threefold increases in GH, and this may contribute to the observed pubertal skeletal phenotype. To clarify the role of GH in skeletal development under conditions of significantly reduced serum IGF-1 levels (but normal tissue IGF-1 levels), we studied the skeletal response of male LID and control mice to GH inhibition by pegvisomant from 4 to 8 weeks of age. Treatment of LID mice with pegvisomant resulted in significant reductions in body weight, femur length (Le), and femur total area (Tt.Ar), as well as further reductions in serum IGF-1 levels by 8 weeks of age, compared with the mean values of vehicle-treated LID mice. Reductions in both Tt.Ar and Le were proportional after treatment with pegvisomant. On the other hand, the relative amount of cortical tissue formed (RCA) in LID mice treated with pegvisomant was significantly less than that in both vehicle-treated LID and control mice, indicating that antagonizing GH action, either directly (through GH receptor signaling inhibition) or indirectly (through further reductions in serum/tissue IGF-1 levels), results in disproportionate reductions in the amount of cortical bone formed. This resulted in bones with significantly reduced mechanical properties (femoral whole-bone stiffness and work to failure were markedly decreased), suggesting that compensatory increases of GH in states of IGF-1 deficiency (LID mice) act to protect against a severe inhibition of bone modeling during growth, which otherwise would result in bones that are too weak for normal and/or extreme loading conditions. Copyright © 2011 American Society for

Puberty as a critical risk period for eating disorders: a review of human and animal studies.

Science.gov (United States)

Klump, Kelly L

2013-07-01

This article is part of a Special Issue "Puberty and Adolescence". Puberty is one of the most frequently discussed risk periods for the development of eating disorders. Prevailing theories propose environmentally mediated sources of risk arising from the psychosocial effects (e.g., increased body dissatisfaction, decreased self-esteem) of pubertal development in girls. However, recent research highlights the potential role of ovarian hormones in phenotypic and genetic risk for eating disorders during puberty. The goal of this paper is to review data from human and animal studies in support of puberty as a critical risk period for eating disorders and evaluate the evidence for hormonal contributions. Data are consistent in suggesting that both pubertal status and pubertal timing significantly impact risk for most eating disorders in girls, such that advanced pubertal development and early pubertal timing are associated with increased rates of eating disorders and their symptoms in both cross-sectional and longitudinal research. Findings in boys have been much less consistent and suggest a smaller role for puberty in risk for eating disorders in boys. Twin and animal studies indicate that at least part of the female-specific risk is due to genetic factors associated with estrogen activation at puberty. In conclusion, data thus far support a role for puberty in risk for eating disorders and highlight the need for additional human and animal studies of hormonal and genetic risk for eating disorders during puberty. Copyright © 2013 Elsevier Inc. All rights reserved.

Secure Infant-Mother Attachment Buffers the Effect of Early-Life Stress on Age of Menarche.

Science.gov (United States)

Sung, Sooyeon; Simpson, Jeffry A; Griskevicius, Vladas; Kuo, Sally I-Chun; Schlomer, Gabriel L; Belsky, Jay

2016-05-01

Prior research indicates that being reared in stressful environments is associated with earlier onset of menarche in girls. In this research, we examined (a) whether these effects are driven by exposure to certain dimensions of stress (harshness or unpredictability) during the first 5 years of life and (b) whether the negative effects of stress on the timing of menarche are buffered by secure infant-mother attachment. Results revealed that (a) exposure to greater harshness (but not unpredictability) during the first 5 years of life predicted earlier menarche and (b) secure infant-mother attachment buffered girls from this effect of harsh environments. By connecting attachment research to its evolutionary foundations, these results illuminate how environmental stressors and relationships early in life jointly affect pubertal timing. © The Author(s) 2016.

The potential adverse effect of energy drinks on executive functions in early adolescence

Directory of Open Access Journals (Sweden)

Tamara Van Batenburg-Eddes

2014-05-01

Full Text Available Introduction. Manufacturers of energy drinks (EDs claim their products improve cognitive performance. Young adolescents are in a critical developmental phase. The impact of ED intake on their development is not yet clear. Therefore, we studied the associations of both caffeine intake and ED consumption with executive functions (EFs, and the role of pubertal status and sleeping problems. Methods. A sample of 509 participants (mean age: 13.1 years, SD 0.85 participated in the study. The level of pubertal development was classified in five pubertal status categories. Participants were asked to report their caffeine (for example coffee and ED consumption for each day of the week. In addition, they indicated sleep quality by reporting problems falling asleep or waking up and/or interrupted sleep. EFs were assessed by self- and parent reports of the Behavior Rating Inventory of Executive Function (BRIEF. Results. Consuming on average one or more ED(s a day was associated with more problems in self-reported behavior regulation and metacognition, and with more problems in parent-reported metacognition. Only high caffeine consumption (two or more cups a day was associated with parent-reported problems with metacognition. The sum of caffeine and ED use was associated with a higher amount of problems with self-reported metacognition and parent reported behavior regulation. The effect estimates for the association between caffeine and ED use combined and EFs did not exceed those of EDs or caffeine separately. Adjusting for pubertal status, gender, educational level, number of sleeping problems and hours of sleep did not change the effect estimates substantially. Conclusion. The observed associations between ED consumption and EFs suggest that regular consumption of EDs - even in moderate amounts – may have a negative impact on daily life behaviors related to EF in young adolescents.

Sex- and brain region-specific patterns of gene expression associated with socially-mediated puberty in a eusocial mammal.

Directory of Open Access Journals (Sweden)

Mariela Faykoo-Martinez

Full Text Available The social environment can alter pubertal timing through neuroendocrine mechanisms that are not fully understood; it is thought that stress hormones (e.g., glucocorticoids or corticotropin-releasing hormone influence the hypothalamic-pituitary-gonadal axis to inhibit puberty. Here, we use the eusocial naked mole-rat, a unique species in which social interactions in a colony (i.e. dominance of a breeding female suppress puberty in subordinate animals. Removing subordinate naked mole-rats from this social context initiates puberty, allowing for experimental control of pubertal timing. The present study quantified gene expression for reproduction- and stress-relevant genes acting upstream of gonadotropin-releasing hormone in brain regions with reproductive and social functions in pre-pubertal, post-pubertal, and opposite sex-paired animals (which are in various stages of pubertal transition. Results indicate sex differences in patterns of neural gene expression. Known functions of genes in brain suggest stress as a key contributing factor in regulating male pubertal delay. Network analysis implicates neurokinin B (Tac3 in the arcuate nucleus of the hypothalamus as a key node in this pathway. Results also suggest an unappreciated role for the nucleus accumbens in regulating puberty.

Environmental factors and puberty timing: expert panel research needs

DEFF Research Database (Denmark)

Louis, G.M. Buck; Jr, L.E. Gray; Marcus, M.

2008-01-01

Serono Symposia International convened an expert panel to review the impact of environmental influences on the regulation of pubertal onset and progression while identifying critical data gaps and future research priorities. An expert panel reviewed the literature on endocrine-disrupting chemicals......, body size, and puberty. The panel concluded that available experimental animal and human data support a possible role of endocrine-disrupting chemicals and body size in relation to alterations in pubertal onset and progression in boys and girls. Critical data gaps prioritized for future research......, and (3) basic research to identify the primary signal(s) for the onset of gonadotropin-releasing hormone-dependent/central puberty and gonadotropin-releasing hormone-independent/peripheral puberty. Prospective studies of couples who are planning pregnancies or pregnant women are needed to capture...

Combined Treatment with Gonadotropin-releasing Hormone Analog and Anabolic Steroid Hormone Increased Pubertal Height Gain and Adult Height in Boys with Early Puberty for Height

OpenAIRE

Tanaka, Toshiaki; Naiki, Yasuhiro; Horikawa, Reiko

2012-01-01

Twenty-one boys with a height of 135 cm or less at onset of puberty were treated with a combination of GnRH analog and anabolic steroid hormone, and their pubertal height gain and adult height were compared with those of untreated 29 boys who enter puberty below 135 cm. The mean age at the start of treatment with a GnRH analog, leuprorelin acetate depot (Leuplin?) was 12.3 yr, a mean of 1.3 yr after the onset of puberty, and GnRH analog was administered every 3 to 5 wk thereafter for a mean d...

Neurokinin B is critical for normal timing of sexual maturation but dispensable for adult reproductive function in female mice.

Science.gov (United States)

True, Cadence; Nasrin Alam, Sayeda; Cox, Kimberly; Chan, Yee-Ming; Seminara, Stephanie B

2015-04-01

Humans carrying mutations in neurokinin B (NKB) or the NKB receptor fail to undergo puberty due to decreased secretion of GnRH. Despite this pubertal delay, many of these patients go on to achieve activation of their hypothalamic-pituitary-gonadal axis in adulthood, a phenomenon termed reversal, indicating that NKB signaling may play a more critical role for the timing of pubertal development than adult reproductive function. NKB receptor-deficient mice are hypogonadotropic but have no defects in the timing of sexual maturation. The current study has performed the first phenotypic evaluation of mice bearing mutations in Tac2, the gene encoding the NKB ligand, to determine whether they have impaired sexual development similar to their human counterparts. Male Tac2-/- mice showed no difference in the timing of sexual maturation or fertility compared with wild-type littermates and were fertile. In contrast, Tac2-/- females had profound delays in sexual maturation, with time to vaginal opening and first estrus occurring significantly later than controls, and initial abnormalities in estrous cycles. However, cycling recovered in adulthood and Tac2-/- females were fertile, although they produced fewer pups per litter. Thus, female Tac2-/- mice parallel humans harboring NKB pathway mutations, with delayed sexual maturation and activation of the reproductive cascade later in life. Moreover, direct comparison of NKB ligand and receptor-deficient females confirmed that only NKB ligand-deficient animals have delayed sexual maturation, suggesting that in the absence of the NKB receptor, NKB may regulate the timing of sexual maturation through other tachykinin receptors.

The effects of oestrogens on linear bone growth

DEFF Research Database (Denmark)

Juul, A

2001-01-01

receptors (ER-alpha and ER-beta) in the human growth plate, and polymorphisms in the ER gene may influence adult height in healthy subjects. Prepubertal oestradiol concentrations are significantly higher in girls than in boys, explaining sex-related differences in pubertal onset. Men with a disruptive......Regulation of linear bone growth in children and adolescents comprises a complex interaction of hormones and growth factors. Growth hormone (GH) is considered to be the key hormone regulator of linear growth in childhood. The pubertal increase in growth velocity associated with GH has traditionally...... been attributed to testicular androgen secretion in boys, and to oestrogens or adrenal androgen secretion in girls. Research data indicating that oestrogen may be the principal hormone stimulating the pubertal growth spurt in boys as well as girls is reviewed. Such an action is mediated by oestrogen...

Weight-bearing exercise and bone mineral accrual in children and adolescents: a review of controlled trials.

Science.gov (United States)

Hind, K; Burrows, M

2007-01-01

Osteoporosis is a serious skeletal disease and as there is currently no cure, there is a large emphasis on its prevention, including the optimisation of peak bone mass. There is increasing evidence that regular weight-bearing exercise is an effective strategy for enhancing bone status during growth. This systematic review evaluates randomised and non-randomised controlled trials to date, on the effects of exercise on bone mineral accrual in children and adolescents. An online search of Medline and the Cochrane database enabled the identification of studies. Those that met the inclusion criteria were included in the review and graded according to risk for bias. Twenty-two trials were reviewed. Nine were conducted in prepubertal children (Tanner I), 8 in early pubertal (Tanner II-III) and 5 in pubertal (Tanner IV-V). Sample sizes ranged from n=10 to 65 per group. Exercise interventions included games, dance, resistance training and jumping exercises, ranging in duration from 3 to 48 months. Approximately half of the trials (n=10) included ground reaction force (GRF) data (2 to 9 times body weight). All trials in early pubertal children, 6 in pre pubertal and 2 in pubertal children, reported positive effects of exercise on bone (P<0.05). Mean increases in bone parameters over 6 months were 0.9-4.9% in prepubertal, 1.1-5.5% in early pubertal and 0.3-1.9% in pubertal exercisers compared to controls (P<0.05). Although weight-bearing exercise appears to enhance bone mineral accrual in children, particularly during early puberty; it remains unclear as to what constitutes the optimal exercise programme. Many studies to date have a high risk for bias and only a few have a low risk. Major limitations concerned selection procedures, compliance rates and control of variables. More well designed and controlled investigations are needed. Furthermore, the specific exercise intervention that will provide the optimal stimulus for peak bone mineral accretion is unclear. Future

Effect of plyometric training on vertical jump height in high school basketball players: randomised control trial

Directory of Open Access Journals (Sweden)

Chhaya Verma, Lakshmi Subramanium, Vijaya Krishnan

2015-01-01

Full Text Available Background: Plyometric involve high intensity eccentric contraction immediately after a powerful concentric contraction. A vertical leap in basketball also involves rapid & repeated muscle contraction & stretching. Various methods have been used to improve the vertical leap in players, but only few studies mention about plyometrics. Aim: To determine the effect of Plyometric training on vertical jump height in high school basketball players & compare them with their untrained counterparts. Methods and Materials: 144 students were randomly selected & distributed in Group I (Pre-pubertal & Group II (Pubertal which was further divided into Group A (trained players & Group B (untrained students. A gender wise distribution followed this. Plyometric training of 6 weeks was conducted & the vertical jump height pre & post training were recorded & compared. Results: Vertical jump height improved significantly post Plyometric in Group Bcompared to Group A. Boys showed improvement in Group B, however girls were better in Group A. Correlation of BMI with vertical jump height was negative & significant in Group B. Conclusion: Plyometric training brought significant change in untrained students. Boys gained more jump height while girls showed significant increase in jump height during pubertal growth spurt. Also, increased BMI reduced jump height.

Genomic analyses identify hundreds of variants associated with age at menarche and support a role for puberty timing in cancer risk.

Science.gov (United States)

Day, Felix R; Thompson, Deborah J; Helgason, Hannes; Chasman, Daniel I; Finucane, Hilary; Sulem, Patrick; Ruth, Katherine S; Whalen, Sean; Sarkar, Abhishek K; Albrecht, Eva; Altmaier, Elisabeth; Amini, Marzyeh; Barbieri, Caterina M; Boutin, Thibaud; Campbell, Archie; Demerath, Ellen; Giri, Ayush; He, Chunyan; Hottenga, Jouke J; Karlsson, Robert; Kolcic, Ivana; Loh, Po-Ru; Lunetta, Kathryn L; Mangino, Massimo; Marco, Brumat; McMahon, George; Medland, Sarah E; Nolte, Ilja M; Noordam, Raymond; Nutile, Teresa; Paternoster, Lavinia; Perjakova, Natalia; Porcu, Eleonora; Rose, Lynda M; Schraut, Katharina E; Segrè, Ayellet V; Smith, Albert V; Stolk, Lisette; Teumer, Alexander; Andrulis, Irene L; Bandinelli, Stefania; Beckmann, Matthias W; Benitez, Javier; Bergmann, Sven; Bochud, Murielle; Boerwinkle, Eric; Bojesen, Stig E; Bolla, Manjeet K; Brand, Judith S; Brauch, Hiltrud; Brenner, Hermann; Broer, Linda; Brüning, Thomas; Buring, Julie E; Campbell, Harry; Catamo, Eulalia; Chanock, Stephen; Chenevix-Trench, Georgia; Corre, Tanguy; Couch, Fergus J; Cousminer, Diana L; Cox, Angela; Crisponi, Laura; Czene, Kamila; Davey Smith, George; de Geus, Eco J C N; de Mutsert, Renée; De Vivo, Immaculata; Dennis, Joe; Devilee, Peter; Dos-Santos-Silva, Isabel; Dunning, Alison M; Eriksson, Johan G; Fasching, Peter A; Fernández-Rhodes, Lindsay; Ferrucci, Luigi; Flesch-Janys, Dieter; Franke, Lude; Gabrielson, Marike; Gandin, Ilaria; Giles, Graham G; Grallert, Harald; Gudbjartsson, Daniel F; Guénel, Pascal; Hall, Per; Hallberg, Emily; Hamann, Ute; Harris, Tamara B; Hartman, Catharina A; Heiss, Gerardo; Hooning, Maartje J; Hopper, John L; Hu, Frank; Hunter, David J; Ikram, M Arfan; Im, Hae Kyung; Järvelin, Marjo-Riitta; Joshi, Peter K; Karasik, David; Kellis, Manolis; Kutalik, Zoltan; LaChance, Genevieve; Lambrechts, Diether; Langenberg, Claudia; Launer, Lenore J; Laven, Joop S E; Lenarduzzi, Stefania; Li, Jingmei; Lind, Penelope A; Lindstrom, Sara; Liu, YongMei; Luan, Jian'an; Mägi, Reedik; Mannermaa, Arto; Mbarek, Hamdi; McCarthy, Mark I; Meisinger, Christa; Meitinger, Thomas; Menni, Cristina; Metspalu, Andres; Michailidou, Kyriaki; Milani, Lili; Milne, Roger L; Montgomery, Grant W; Mulligan, Anna M; Nalls, Mike A; Navarro, Pau; Nevanlinna, Heli; Nyholt, Dale R; Oldehinkel, Albertine J; O'Mara, Tracy A; Padmanabhan, Sandosh; Palotie, Aarno; Pedersen, Nancy; Peters, Annette; Peto, Julian; Pharoah, Paul D P; Pouta, Anneli; Radice, Paolo; Rahman, Iffat; Ring, Susan M; Robino, Antonietta; Rosendaal, Frits R; Rudan, Igor; Rueedi, Rico; Ruggiero, Daniela; Sala, Cinzia F; Schmidt, Marjanka K; Scott, Robert A; Shah, Mitul; Sorice, Rossella; Southey, Melissa C; Sovio, Ulla; Stampfer, Meir; Steri, Maristella; Strauch, Konstantin; Tanaka, Toshiko; Tikkanen, Emmi; Timpson, Nicholas J; Traglia, Michela; Truong, Thérèse; Tyrer, Jonathan P; Uitterlinden, André G; Edwards, Digna R Velez; Vitart, Veronique; Völker, Uwe; Vollenweider, Peter; Wang, Qin; Widen, Elisabeth; van Dijk, Ko Willems; Willemsen, Gonneke; Winqvist, Robert; Wolffenbuttel, Bruce H R; Zhao, Jing Hua; Zoledziewska, Magdalena; Zygmunt, Marek; Alizadeh, Behrooz Z; Boomsma, Dorret I; Ciullo, Marina; Cucca, Francesco; Esko, Tõnu; Franceschini, Nora; Gieger, Christian; Gudnason, Vilmundur; Hayward, Caroline; Kraft, Peter; Lawlor, Debbie A; Magnusson, Patrik K E; Martin, Nicholas G; Mook-Kanamori, Dennis O; Nohr, Ellen A; Polasek, Ozren; Porteous, David; Price, Alkes L; Ridker, Paul M; Snieder, Harold; Spector, Tim D; Stöckl, Doris; Toniolo, Daniela; Ulivi, Sheila; Visser, Jenny A; Völzke, Henry; Wareham, Nicholas J; Wilson, James F; Spurdle, Amanda B; Thorsteindottir, Unnur; Pollard, Katherine S; Easton, Douglas F; Tung, Joyce Y; Chang-Claude, Jenny; Hinds, David; Murray, Anna; Murabito, Joanne M; Stefansson, Kari; Ong, Ken K; Perry, John R B

2017-06-01

The timing of puberty is a highly polygenic childhood trait that is epidemiologically associated with various adult diseases. Using 1000 Genomes Project-imputed genotype data in up to ∼370,000 women, we identify 389 independent signals (P < 5 × 10 -8 ) for age at menarche, a milestone in female pubertal development. In Icelandic data, these signals explain ∼7.4% of the population variance in age at menarche, corresponding to ∼25% of the estimated heritability. We implicate ∼250 genes via coding variation or associated expression, demonstrating significant enrichment in neural tissues. Rare variants near the imprinted genes MKRN3 and DLK1 were identified, exhibiting large effects when paternally inherited. Mendelian randomization analyses suggest causal inverse associations, independent of body mass index (BMI), between puberty timing and risks for breast and endometrial cancers in women and prostate cancer in men. In aggregate, our findings highlight the complexity of the genetic regulation of puberty timing and support causal links with cancer susceptibility.

Backstroke Technical Characterization of 11-13 Year-Old Swimmers

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Ana Filipa Silva

2013-12-01

Full Text Available The aim of this study was to characterize the backstroke swimming technique of 11-13 year-old swimmers when performing at very high intensity. A sample of 114 swimmers was divided into four groups regarding maturational and gender effect, who performed 25- m backstroke swimming at 50-m pace. Using two underwater cameras the general biomechanical parameters (speed, stroke rate, stroke length and stroke index, the arm stroke phases and two indexes of arm coordination (Index of Coordination 1, which characterizes the continuity between propulsive phases of each arm and Index of Coordination 2 that evaluates the simultaneity between the beginning of the pull of one arm and of the recovery of the other arm were measured. Post- pubertal swimmers achieved higher values of speed (1.06 ± 0.14 and 1.18 ± 0.14 m·s-1 for pubertal and 1.13 ± 0.14 and 1.24 ± 0.12 m·s-1 for post-pubertal girl and boy swimmers, respectively, stroke length (1.64 ± 0.26 and 1.68 ± 0.25 m·cycle-1 for pubertal and 1.79 ± 0.22 and 1.75 ± 0.27 m·cycle-1 for post-pubertal girls and boys, respectively and stroke index. Regar-ding genders, male were faster than female swimmers. Boys also showed a higher stroke rate and stroke index than girls, who achieved higher results in the ratio between stroke length and arm span. As it was expected, no hand lag time was noticed in young swimmers. Although no differences were noticed between genders, the Index of Coordination 1 was in catch-up mode (-9.89 ± 3.16 and -10.16 ± 3.60 % for girls and -9.77 ± 2.93 and -10.39 ± 2.44 % for boys pubertal and post-pubertal, respectively and the Index of Coordination 2 was in superposition mode (1.86 ± 4.39 and 2.25 ± 2.25 % from girls and 1.72 ± 2.62 and 1.95 ± 2.95 % for boys, pubertal and post-pubertal, respectively.

Environmental factors and puberty timing: Expert panel research needs

Science.gov (United States)

An expert panel reviewed the literature on endocrine disrupting chemicals (EDCs), body size and puberty. The panel concluded that available experimental animal and human data support a possible role of EDCs and body size in relation to alterations in pubertal onset and progressio...

Treatment timing for functional jaw orthopaedics followed by fixed appliances: a controlled long-term study.

Science.gov (United States)

Pavoni, Chiara; Lombardo, Elisabetta Cretella; Lione, Roberta; Faltin, Kurt; McNamara, James A; Cozza, Paola; Franchi, Lorenzo

2017-11-01

To evaluate the role of treatment timing on long-term dentoskeletal effects of Class II treatment with removable functional appliances followed by full-fixed appliance therapy. A group of 46 patients (23 females and 23 males) with Class II malocclusion treated consecutively with either Bionator or Activator, followed by fixed appliances was compared with a matched control group of 31 subjects (16 females and 15 males) with untreated Class II malocclusion. The treated sample was evaluated at T1, start of treatment (mean age: 9.9 ± 1.3 years); T2, end of functional treatment and prior to fixed appliances (mean age: 11.9 ± 1.3 years); and T3, long-term observation (mean age: 18.3 ± 2.1 years). The treated and the control samples were divided into pre-pubertal and pubertal groups according to skeletal maturity observed at the start of treatment. Statistical comparisons were performed with independent sample t-tests. When treatment was initiated before puberty, Class II correction was mostly confined to the dentoalveolar changes, with significant improvements of both overjet and molar relationships. On the other hand, treatment with the outset at puberty produced significant long-term improvement of sagittal skeletal relationships, which were mainly sustained by mandibular changes. Treatment with removable functional appliances (Bionator or Activator) followed by full-fixed appliances produced significant skeletal long-term changes when it begins at puberty. Prepubertal Class II treatment results primarily in dentoalveolar changes. © The Author 2017. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com

Bone mineral density, growth, pubertal development and other parameters in Brazilian children and young adults with sickle cell anaemia.

Science.gov (United States)

Meeuwes, M; Souza de Carvalho, T F; Cipolotti, R; Gurgel, R Q; Ferrão, T O; Peters, M; Agyemang, C

2013-12-01

To evaluate the occurrence of low bone mineral density (BMD) and its relationship with clinical and laboratorial characteristics in children and young adults with sickle cell anaemia living in Northeast-Brazil, and to assess the role of radiography in diagnosing low BMD. Bone mineral density of lumbar spine was measured by dual energy X-ray absorptiometry (DXA) in 27 patients with Sickle cell anaemia (SCA) aged 7-28 years. Clinical history, calcium and calorie intake, laboratory measurements, anthropometrics and pubertal development were assessed, and X-rays were obtained. Z-scores and T-scores for weight, height, Body Mass Index (BMI) and BMD were calculated using age and gender matched reference data. Mean lumbar spine BMD Z-scores and T-scores were -1.81 SD in boys and -0.80 SD in girls. BMD Z-scores were below -2 SD in 33.3% of girls and in 46.7% of boys. Low BMD (developing low BMD. © 2013 John Wiley & Sons Ltd.

Social anxiety and the cortisol response to social evaluation in children and adolescents.

Science.gov (United States)

van den Bos, Esther; Tops, Mattie; Westenberg, P Michiel

2017-04-01

Contradictory findings have been reported on the relation between social anxiety and the cortisol response to social evaluation in youth. The present longitudinal study aimed to clarify this relation by taking pubertal development into account. Data were collected in two waves, two years apart, for a community sample of 196 participants, aged 8-17 years at Time 1. Pubertal development and social anxiety were assessed with self-report questionnaires. Salivary cortisol was obtained before and after participants completed the Leiden Public Speaking Task. Data were analyzed using regression analysis with clustered bootstrap. The dependent variable was the cortisol area under the curve. Social anxiety and pubertal development scores were decomposed into between- and within-participants components. Between participants, the relation between social anxiety and the cortisol response to public speaking varied with pubertal development: socially anxious individuals showed higher responses at low levels of pubertal development, but lower responses at high levels of pubertal development. Within participants, an increase in social anxiety over time was associated with a lower cortisol response. The results are in line with the suggestion that the responses of socially anxious individuals change from elevated in childhood to attenuated in adolescence and adulthood. Attenuation of the cortisol response is explained by theories proposing that the stress response changes with the duration of the stressor. Copyright © 2017 Elsevier Ltd. All rights reserved.

Alteraciones puberales en adolescentes con leucemia en fase de vigilancia.

Science.gov (United States)

Arriaga-Cázares, Héctor Eliud; Cázares-Bellazetin, Mara Alejandra; Sánchez-Sánchez, Luz María; Bahena-García, Ana Laura; Palacios-Saucedo, Gerardo Del Carmen

2017-01-01

To evaluate which factors are associated with alterations in pubertal development in pediatric patients with leukemia in the surveillance phase. A case-control study was carried out, including patients aged 8-14 years with diagnosis of acute lymphoblastic leukemia under surveillance. Demographic data were collected, age at diagnosis, type of leukemia, risk of leukemia, duration and type of treatment received, time of surveillance phase; and pubertal development was assessed by Tanner stage, bone age, pelvic ultrasound for women, and LH levels. Fisher's exact test and Mann-Whitney U-test were used. Twenty-five pediatric patients with a diagnosis of acute lymphoblastic leukemia between 8 and 14 years of age with a median of 8 were included, only 4 (16%) presented pubertal alterations, 1 had pubertal delay and 3 advanced puberty. The history of radiotherapy was related to pubertal alterations (p = 0.03). The antecedent of having received radiotherapy as part of the treatment in patients with acute lymphoblastic leukemia is a risk factor for developing pubertal abnormalities. Copyright: © 2017 SecretarÍa de Salud

Prenatal and adult exposures to smoking are associated with adverse effects on reproductive hormones, semen quality, final height and body mass index

DEFF Research Database (Denmark)

Ravnborg, Trine L; Jensen, Tina K; Andersson, Anna-Maria

2011-01-01

BACKGROUND Exposure to tobacco smoking prenatally is a risk factor for reduced semen quality, but whether the exposure has adverse effects on reproductive hormones, pubertal development or adult BMI remain largely unexplored. The aim of this study was to investigate the associations between...... these factors while controlling for the effects of current smoking in young adulthood. METHODS This cross-sectional study (1996-2006) included 3486 Danish men (median age: 19 years), participating in a semen-quality study. Data were obtained from questionnaires, physical examinations, semen analyses...... and assessments of reproductive hormones. The main outcome measures were markers of pubertal onset, BMI, reproductive hormones and semen variables. RESULTS Maternal smoking during pregnancy was associated with earlier onset of puberty (e.g. early pubic hair development in 25.2 versus 18.9% of unexposed subjects...

effect of continous light and darkness exposures on the pituitary

African Journals Online (AJOL)

Dr Olaleye

The effects of constant light and dark exposure of pubertal male rats on the pituitary-gonadal axis and thyroid activity were studied. ... In the rats exposed to continuous light, the weight of the thyroid gland increased significantly (P<0.02) and the serum level of T4 also ... 3minutes) per day when food in the cages was being.

Association between Physical Activity and Cardiovascular Risk in Chinese Youth Independent of Age and Pubertal Stage

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Lau Joseph TF

2010-06-01

Full Text Available Abstract Background Childhood and adolescence are critical periods of habit formation with substantial tracking of lifestyle and cardiovascular risk into adulthood. There are various guidelines on recommended levels of physical activity in youth of school-age. Despite the epidemic of obesity and diabetes in China, there is a paucity of data in this regard in Chinese youth. We examined the association of self-reported level of physical activity and cardiovascular risk in Hong Kong Chinese youth of school-age. Methods This was a cross-sectional study conducted in 2007-8 in a school setting with 2119 Hong Kong Chinese youth aged 6-20 years. Physical activity level was assessed using a validated questionnaire, CUHK-PARCY (The Chinese University of Hong Kong: Physical Activity Rating for Children and Youth. A summary risk score comprising of waist circumference, blood pressure, fasting plasma glucose and lipids was constructed to quantify cardiovascular risk. Results In this cohort, 21.5% reported high level of physical activity with boys being more active than girls (32.1% versus 14.1%, p Conclusion Self-reported level of physical activity is associated with cardiovascular risk factors in Chinese youth after adjusting for sex and pubertal stage.

Delayed nootropic effects of arginine vasopressin after early postnatal chronic administration to albino rat pups.

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Kim, P A; Voskresenskaya, O G; Kamensky, A A

2009-06-01

Intranasal administration of arginine vasopressin (10 microg/kg) to albino rat pups had a strong nootropic effect during training with positive and negative reinforcement. This effect was different in animals of various age groups: training with positive reinforcement was improved in "adolescent" rats and pubertal animals, while during training with negative reinforcement, the nootropic effect of the peptide was more prolonged and persisted also in adult animals.

Adrenergic system participation on LH secretion in pre-pubertal Nelore heifers Participação do sistema adrenérgico na secreção de LH, em novilhas nelores

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Guilherme Paula Nogueira

2008-12-01

Full Text Available The aim of this study was to evaluate the response of clonidine administration (alfa-adrenoceptor agonist, 10g/kg body weight, i.v. and blood collected every 15 min for 4 h thereafter on luteinizing hormone (LH secretion in B. indicus pre-pubertal heifers at 8, 12 e 15 months of age. LH was quantified by RIA, sensitivity (0.05 ng/mL and coefficient of variation (20.39%. Alfa-adrenoceptor action (clonidine reduced (P<0,05 basal LH and time to greatest peak occurrence at 15 months-old and increased (P>0,05 peak total area and area of highest peak of LH secretion to 8 months-old. The results suggest reduced hypothalamic sensibility by gonadal steroid in pre-pubertal Nelore heifer maturation sexual and clonidine neurotransmitter participation, either stimulating or inhibiting LH secretion.Objetivou-se com este trabalho investigar a variação na secreção do hormônio luteinizante (LH em resposta ao tratamento com clonidina (agonista alfa-adrenérgico, 10µg/kg, i.v., amostras 15 min por 4h, em novilhas da raça Nelore pré-púberes aos 8, 12 e 15 meses de idade. A concentração de LH foi quantificada por radioimunoensaio, sensibilidade de 0,05 ng/mL e coeficiente de variação de 20,39%. A ativação de receptores alfa-adrenérgicos por intermédio da clonidina diminuiu (P<0,05 a concentração de LH e o tempo necessário para o aparecimento do maior pico de LH aos 15 meses de idade e aumentou (P>0,05 a área total e área do maior pico de secreção de LH aos 8 meses de idade. Os resultados indicam diminuição da sensibilidade do hipotálamo aos esteróides gonadais durante o processo de maturação sexual nas novilhas da raça Nelore e a participação da clonidina como neurotransmissora.

The timing of normal puberty and the age limits of sexual precocity

DEFF Research Database (Denmark)

Parent, Anne-Simone; Teilmann, Grete; Juul, Anders

2003-01-01

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western European...... countries. These observations are raising the issues of current differences and secular trends in timing of puberty in relation to ethnic, geographical, and socioeconomic background. None of these factors provide an unequivocal explanation for the earlier onset of puberty seen in the United States....... In the formerly deprived migrating children, refeeding and catch-up growth may prime maturation. However, precocious puberty is seen also in some nondeprived migrating children. Attention has been paid to the changing milieu after migration, and recently, the possible role of endocrine- disrupting chemicals from...

Modulation of mammary gland development in pre-pubertal mice as affected by soya and milk protein supplements.

Science.gov (United States)

Alston-Mills, Brenda; Lepri, J J; Martin, C A

2011-08-01

The objective of the present study was to determine the effects of soya and whey milk protein, α-lactalbumin (α-LA), on mammary gland morphology and the structural support of the gland, in pre-pubertal mice after 7 d of treatment. In Expt 1, weaned (day 21) CD1 mice were given one of the four treatments, three included dietary supplements: (1) control diet, casein, (2) soya, (3) α-LA and (4) subcutaneous injection of 2·5 μg oestradiol benzoate in 20 μl maize oil and fed the control diet. All diets were isoenergetic with equal protein concentrations. All groups that were not treated with oestradiol received the vehicle. Whole-mount analyses were performed to determine longitudinal ductal growth and terminal end bud development. DNA was extracted from the gland and assessed by spectrophotometry (260/280 nm). Tissue extracts for extracellular matrix (ECM) proteins, matrix metalloproteinase-2 (MMP(2)), tissue inhibitor of MMP(2) (TIMP(2)), and serum oestradiol and mammary tissue epidermal growth factors (EGF) were measured by immunoassays. Expt 2 utilised the Her2/neu transgenic strain, with the same protocols. Statistical significance was determined by one-way ANOVA. From Expt 1 and 2, soya and α-LA significantly increased ductal elongation when compared with the oestrogen and control groups. These results were corroborated by data on total DNA and the ratio of MMP(2):TIMP(2). The ratio of MMP(2):TIMP(2) was affected by α-LA. Serum oestradiol was decreased only in the oestradiol-treated groups in both experiments. Soya is known to be oestrogenic and can act on epithelia directly. The mechanism by which α-LA affects glandular development is by modulating the ECM or by promoting the synthesis/activity of EGF.

Evaluation of 451 Danish Boys With Delayed Puberty

DEFF Research Database (Denmark)

Lawaetz, Jacob Gerner; P. Hagen, Casper; Mieritz, Mikkel Grunnet

2015-01-01

Context: Few data exist on the diagnostic criteria, and on the effects of puberty induction, in boyswith constitutional delay in growth and puberty (CDGP). Objective: To develop puberty nomograms based on Danish boys with normal pubertal development.To evaluate the different diagnostic criteria...... and the effect of oral testosterone undecanoate(TU) in boys with CDGP. Design: A cross-sectional and longitudinal study of Danish boys with normal pubertal development(COPENHAGEN puberty study). A retrospective observational study of 451 boys evaluated fordelayed puberty between 1990 and 2013. Setting: Tertiary...... by the puberty nomogram(genital stage 2 SD for age) versus the classical criteria (genital stage 1 at 14 years). The effectof one year of oral TU treatment on pubertal progression, circulating hormones, height, andpredicted adult height (PAH). Results: Seventy-eight (27%) of the 287 boys had delayed pubertal...

[Evaluation of the nutrition mode in children during the pubertal period with BMI < or = 5 percentile in the city of Szczecin].

Science.gov (United States)

Goluch-Koniuszy, Zuzanna

2010-01-01

This research was aimed at evaluation of the method of nutrition in the children aged 13 during the period of pubertal spurt who had their body mass, body weight and this values led to calculation of BMI indicator which was related to centile distribution of children from Warszawa. From the group 1464 children selected 79 persons (5.4% the whole of investigated) with BMI < or = 5 percentile with underweight and considerable underweight. Their menus of three chosen at random weekdays were obtained. Analysis of the nutrition method of children with underweight and considerable underweight showed low energy value of the diet, cellulose, mineral components (K, Ca, Mg) also liquids deficiency at simultaneously occurrent the general and animal protein, the fat, the cholesterol, mineral components (Na, P, Fe, Cu, Zn), vitamins A, C, E (girls) and from the group B. The children have undergone a special pro health education in the form "live" workshop.

Risk of Hyperprolactinemia and Sexual Side Effects in Males 10-20 Years Old Diagnosed with Autism Spectrum Disorders or Disruptive Behavior Disorder and Treated with Risperidone

NARCIS (Netherlands)

Roke, Yvette; Buitelaar, Jan K.; Boot, Annemieke M.; Tenback, Diederik; van Harten, Peter N.

2012-01-01

Objective: The aim of this study was to investigate the long-term treatment effects of risperidone on prolactin levels and prolactin-related side effects in pubertal boys with autism spectrum disorders (ASD) and disruptive behavior disorders (DBD). Method: Physical healthy 10-20-year-old males with

Artistic versus rhythmic gymnastics: effects on bone and muscle mass in young girls.

Science.gov (United States)

Vicente-Rodriguez, G; Dorado, C; Ara, I; Perez-Gomez, J; Olmedillas, H; Delgado-Guerra, S; Calbet, J A L

2007-05-01

We compared 35 prepubertal girls, 9 artistic gymnasts and 13 rhythmic gymnasts with 13 nonphysically active controls to study the effect of gymnastics on bone and muscle mass. Lean mass, bone mineral content and areal density were measured by dual energy X-ray absorptiometry, and physical fitness was also assessed. The artistic gymnasts showed a delay in pubertal development compared to the other groups (partistic gymnasts had a 16 and 17 % higher aerobic power and anaerobic capacity, while the rhythmic group had a 14 % higher anaerobic capacity than the controls, respectively (all partistic gymnasts had higher lean mass (partistic and the rhythmic gymnasts (partistic group compared to the other groups. Lean mass strongly correlated with bone mineral content (r=0.84, partistic gymnastic participation is associated with delayed pubertal development, enhanced physical fitness, muscle mass, and bone density in prepubertal girls, eliciting a higher osteogenic stimulus than rhythmic gymnastic.

Urinary gonadotrophins: a useful non-invasive marker of activation of the hypothalamic pituitary-gonadal axis

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McNeilly Jane D

2012-05-01

Full Text Available Abstract Background Non-invasive screening investigations are rarely used for assessing the activation and progression of the hypothalamic-pituitary gonadal axis through puberty. This study aimed to establish a normal range for urinary gonadotrophins in children progressing through puberty. Methods Urine samples were collected from 161 healthy school children (76 boys, 85 girls aged 4–19 yrs. Height and weight were converted to standard deviation score. Pubertal status, classified by Tanner staging, was determined by self-assessment. Urinary gonadotrophins were measured by chemiluminescent microparticle immunoassay. Results were grouped according to pubertal status (pre-pubertal or pubertal. Results Of the 161 children, 50 were pre-pubertal (28 boys; 22 girls and 111 were pubertal (48 boys; 63 girls. Overall, urinary gonadotrophins concentrations increased with pubertal maturation. All pre-pubertal children had a low urinary LH:Creatinine ratio. LH:Creatinine ratios were significantly higher in pubertal compared to pre-pubertal boys (pp = 0.006. However, LH:FSH ratios were a more consistent discriminant between pre-pubertal and pubertal states in both sexes (Boys 0.45 pubertal vs 0.1 pre-pubertal; girls 0.23 pubertal vs 0.06 pre-pubertal. Conclusion Urinary gonadotrophins analyses could be used as non-invasive integrated measurement of pubertal status which reflects clinical/physical status.

NCI, NHLBI/PBMTC First International Conference on Late Effects after Pediatric Hematopoietic Cell Transplantation: Endocrine Challenges--Thyroid Dysfunction, Growth Impairment, Bone Health, & Reproductive Risks

Science.gov (United States)

Dvorak, Christopher C.; Gracia, Clarisa R.; Sanders, Jean E.; Cheng, Edward Y.; Baker, K. Scott; Pulsipher, Michael A.; Petryk, Anna

2011-01-01

The endocrine system is highly susceptible to damage by high-dose chemotherapy and/or irradiation prior to hematopoietic cell transplantation (HCT) during childhood. The specific endocrine organs most affected by HCT include the thyroid gland, the pituitary, and the gonads. In addition, hormones that support development and stability of the skeletal system are also affected. Insufficiency of thyroid hormone is one of the most common late sequelae of HCT, and occurs more often in young children. Deficiency in the pituitary’s production of growth hormone is a problem of unique concern to the pediatric population. The reproductive risks of HCT depend on the patient’s gender and pubertal status at the time of HCT. Pubertal or gonadal failure frequently occurs, especially in females. Infertility risks for both genders remain high, while methods of fertility preservation are limited in all but post-pubertal males. Bone health post-HCT can be compromised by low bone mineral density as well as avascular necrosis, but the data on both problems in the pediatric HCT population are limited. In this paper, the current state of knowledge, gaps in that knowledge, and recommendations for future research are addressed in detail for each of these systems. PMID:22005649

Evaluation of GnRH analogue testing in diagnosis and management of children with pubertal disorders

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Hemchand K Prasad

2012-01-01

Full Text Available Context: Gonadotrophin releasing hormone (GnRH stimulation test is pivotal in the assessment of children with pubertal disorders. However, lack of availability and high cost often result in the test falling into disfavor. We routinely use the GnRH analogue stimulation test as an alternative at our center. Aim: To present the data on children with endocrine disorders who underwent GnRH agonist stimulation test in pediatric endocrine clinic of a tertiary care referral hospital. Setting and Design: Pediatric endocrine clinic of a tertiary care referral hospital. Retrospective analysis of case records. Materials and Methods: The details pertaining to clinical and radiological parameters and hormonal tests were retrieved from case records of 15 children who underwent GnRH agonist stimulation test from May 2010 to April 2011. Results: Indications for testing with GnRH analogue were evaluation of delayed puberty, diagnosis of precocious puberty, assessment of hormonal suppression in treatment of precocious puberty and micropenis in two, nine, three and one cases, respectively. The results of the test and clinical and radiological parameters were in concordance. The test was also crucial in diagnosing the onset of central precocious puberty in two children with congenital adrenal hyperplasia. Conclusion: GnRH agonist test is a convenient, safe test that can be performed on an out-patient basis and can help the clinicians in the correct diagnosis and appropriate treatment of various puberty-related disorders.

Peripheral markers of serotonergic and noradrenergic function in post-pubertal, caucasian males with autistic disorder.

Science.gov (United States)

Croonenberghs, J; Delmeire, L; Verkerk, R; Lin, A H; Meskal, A; Neels, H; Van der Planken, M; Scharpe, S; Deboutte, D; Pison, G; Maes, M

2000-03-01

Some studies have suggested that disorders in the peripheral and central metabolism of serotonin (5-HT) and noradrenaline may play a role in the pathophysiology of autistic disorder. This study examines serotonergic and noradrenergic markers in a study group of 13 male, post-pubertal, caucasian autistic patients (age 12-18 y; I.Q. > 55) and 13 matched volunteers. [3H]-paroxetine binding Kd values were significantly higher in patients with autism than in healthy volunteers. Plasma concentrations of tryptophan, the precursor of 5-HT, were significantly lower in autistic patients than in healthy volunteers. There were no significant differences between autistic and normal children in the serum concentrations of 5-HT, or the 24-hr urinary excretion of 5-hydroxy-indoleacetic acid (5-HIAA), adrenaline, noradrenaline, and dopamine. There were no significant differences in [3H]-rauwolscine binding Bmax or Kd values, or in the serum concentrations of tyrosine, the precursor of noradrenaline, between both study groups. There were highly significant positive correlations between age and 24-hr urinary excretion of 5-HIAA and serum tryptophan. The results suggest that: 1) serotonergic disturbances, such as defects in the 5-HT transporter system and lowered plasma tryptophan, may play a role in the pathophysiology of autism; 2) autism is not associated with alterations in the noradrenergic system; and 3) the metabolism of serotonin in humans undergoes significant changes between the ages of 12 and 18 years.

Effects of age, gender, BMI, and anatomical site on skin thickness in children and adults with diabetes.

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José G B Derraik

Full Text Available We aimed to assess the effects of age, sex, body mass index (BMI, and anatomical site on skin thickness in children and adults with diabetes.We studied 103 otherwise healthy children and adolescents with type 1 diabetes aged 5-19 years, and 140 adults with type 1 and type 2 diabetes aged 20-85 years. The thicknesses of both the dermis and subcutis were assessed using ultrasound with a linear array transducer, on abdominal and thigh skin.There was an age-related thickening of both dermis (p<0.0001 and subcutis (p = 0.013 in children and adolescents. Girls displayed a substantial pubertal increase in subcutis of the thigh (+54%; p = 0.048 and abdomen (+68%; p = 0.009. Adults showed an age-related decrease in dermal (p = 0.021 and subcutis (p = 0.009 thicknesses. Pubertal girls had a thicker subcutis than pubertal boys in both thigh (16.7 vs 7.5 mm; p<0.0001 and abdomen (16.7 vs 8.8 mm; p<0.0001. Men had greater thigh dermal thickness than women (1.89 vs 1.65 mm; p = 0.003, while the subcutis was thicker in women in thigh (21.3 vs 17.9 mm; p = 0.012 and abdomen (17.7 vs 9.8 mm; p<0.0001. In boys, men, and women, both dermis and subcutis were thicker on the abdomen compared to thigh; in girls this was only so for dermal thickness. In both children and adults, the skin (dermis and subcutis became steadily thicker with increasing BMI (p<0.0001.Skin thickness is affected by age, pubertal status, gender, BMI, and anatomical site. Such differences may be important when considering appropriate sites for dermal/subcutaneous injections and other transdermal delivery systems.

The relationship between obesity and body compositions with respect to the timing of puberty in Chongqing adolescents: a cross-sectional study.

Science.gov (United States)

He, Fang; Guan, Peiyu; Liu, Qin; Crabtree, Donna; Peng, Linli; Wang, Hong

2017-08-18

It is well known that excess adiposity during childhood may influence pubertal development. However, the extent to which body compositions vary in throughout puberty in boys and girls is currently unknown. The aim of this study was to investigate whether obesity and body compositions correlate with the timing of puberty in boys and girls. By random cluster sampling, our study analyzed data from 1472 students (690 girls, 782 boys) aged 6-17 years from two schools in the Chongqing area. Data were collected by physical examination of weight, height, and skinfold thicknesses. Testicular volume was measured in boys and breast development in girls. By which we got the indicators of obesity, timing of puberty and body compositions. Probit regression analysis was used to group subjects into early puberty (>P 25 ), on-time puberty (P 25  ~ P 75 ), and delayed puberty (puberty groups by sex. Multivariate analysis of covariance was used to examine the association between timing of puberty and body composition indicators. There were significant differences in the distribution of fat levels (normal weigh, overweight, obesity) among different pubertal groups in different sex (boys:χ2 = 10.639, P = 0.031; girls:χ2 = 63.232, P = 0.000). Multivariate analysis of covariance showed that percentage of body fat, fat mass and fat-free mass in the delayed puberty girls were significantly lower than the girls in the on-time puberty and early puberty, while body density had the opposite result (all P puberty groups (all P > 0.05). In girls, delayed puberty was negatively correlated with Obesity, percentage of body fat, fat mass and fat-free mass, and positively correlated with body density. But in boys, delayed puberty was only negatively correlated with Obesity, the relation between puberty and body compositions was not found.

Protein malnutrition during gestation and early life decreases neuronal size in the medial prefrontal cortex of post-pubertal rats

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Roelf J. Cruz-Rizzolo

2017-12-01

Full Text Available Retrospective studies in human populations indicate that protein deprivation during pregnancy and early life (early protein malnutrition, EPM is associated with cognitive impairments, learning disabilities and may represent a risk factor for the late onset of some psychiatric disorders, fundamentally schizophrenia, a condition where the prefrontal cortex plays an important role. The purpose of this study was to analyze whether EPM affects structural aspects of the rat medial prefrontal cortex (mPFC, such as cortical volume, neuronal density and neuronal soma size, which seem altered in patients with schizophrenia. For this, a rat model of EPM (5% casein from conception to postnatal day 60 was adopted and the rat mPFC volume, total number of neurons and average neuronal volume were evaluated on postnatal day 60 (post-pubertal animals by histo- and immunohistochemical techniques using unbiased stereological analysis. EPM did not alter the number of NeuN+ neurons in the rat mPFC. However, a very significant decrease in mPFC volume and average neuronal size was observed in malnourished rats. Although the present study does not establish causal relationships between malnutrition and schizophrenia, our results may indicate a similar structural phenomenon in these two situations.

7 CFR 953.65 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 953.65 Section 953.65 Agriculture... STATES Order Regulating Handling Effective Time and Termination § 953.65 Effective time. The provisions of this subpart shall become effective at such time as the Secretary may declare above his signature...

7 CFR 946.62 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 946.62 Section 946.62 Agriculture... Order Regulating Handling Effective Time and Termination § 946.62 Effective time. The provisions of this subpart shall become effective at such time as the Secretary may declare above his signature attached to...

Proandrogenic and Antiandrogenic Progestins in Transgender Youth: Differential Effects on Body Composition and Bone Metabolism.

Science.gov (United States)

Tack, Lloyd J W; Craen, Margarita; Lapauw, Bruno; Goemaere, Stefan; Toye, Kaatje; Kaufman, Jean-Marc; Vandewalle, Sara; T'Sjoen, Guy; Zmierczak, Hans-Georg; Cools, Martine

2018-06-01

Progestins can be used to attenuate endogenous hormonal effects in late-pubertal transgender (trans) adolescents (Tanner stage B4/5 and G4/5). Currently, no data are available on the effects of progestins on the development of bone mass or body composition in trans youth. To study prospectively the evolution of body composition and bone mass in late-pubertal trans adolescents using the proandrogenic or antiandrogenic progestins lynestrenol (L) and cyproterone acetate (CA), respectively. Forty-four trans boys (Tanner B4/5) and 21 trans girls (Tanner G4/5) were treated with L or CA for 11.6 (4 to 40) and 10.6 (5 to 31) months, respectively. Anthropometry, grip strength, body composition, and bone mass, size, and density were determined by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography before the start of progestin and before addition of cross-sex hormones. Using L, lean mass [+3.2 kg (8.6%)] and grip strength [+3 kg (10.6%)] significantly increased, which coincided with a more masculine body shape in trans boys. Trans girls showed loss of lean mass [-2.2 kg (4.7%)], gain of fat mass [+1.5 kg (9.4%)], and decreased grip strength Z scores. CA limited normal bone expansion and impeded pubertal bone mass accrual, mostly at the lumbar spine [Z score: -0.765 to -1.145 (P = 0.002)]. L did not affect physiological bone development. Proandrogenic and antiandrogenic progestins induce body composition changes in line with the desired appearance within 1 year of treatment. Bone health, especially at the lumbar spine, is of concern in trans girls, as bone mass accrual is severely affected by androgen suppressive therapy.

7 CFR 947.70 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 947.70 Section 947.70 Agriculture... Effective Time and Termination § 947.70 Effective time. (a) The provisions of this subpart shall become effective at such time as the Secretary may declare above his signature attached to this subpart, and shall...

Developmental programming by androgen affects the circadian timing system in female mice.

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Mereness, Amanda L; Murphy, Zachary C; Sellix, Michael T

2015-04-01

Circadian clocks play essential roles in the timing of events in the mammalian hypothalamo-pituitary-ovarian (HPO) axis. The molecular oscillator driving these rhythms has been localized to tissues of the HPO axis. It has been suggested that synchrony among these oscillators is a feature of normal reproductive function. The impact of fertility disorders on clock function and the role of the clock in the etiology of endocrine pathology remain unknown. Polycystic ovarian syndrome (PCOS) is a particularly devastating fertility disorder, affecting 5%-10% of women at childbearing age with features including a polycystic ovary, anovulation, and elevated serum androgen. Approximately 40% of these women have metabolic syndrome, marked by hyperinsulinemia, dyslipidemia, and insulin resistance. It has been suggested that developmental exposure to excess androgen contributes to the etiology of fertility disorders, including PCOS. To better define the role of the timing system in these disorders, we determined the effects of androgen-dependent developmental programming on clock gene expression in tissues of the metabolic and HPO axes. Female PERIOD2::luciferase (PER2::LUC) mice were exposed to androgen (dihydrotestosterone [DHT]) in utero (Days 16-18 of gestation) or for 9-10 wk (DHT pellet) beginning at weaning (pubertal androgen excess [PAE]). As expected, both groups of androgen-treated mice had disrupted estrous cycles. Analysis of PER2::LUC expression in tissue explants revealed that excess androgen produced circadian misalignment via tissue-dependent effects on phase distribution. In vitro treatment with DHT differentially affected the period of PER2::LUC expression in tissue explants and granulosa cells, indicating that androgen has direct and tissue-specific effects on clock gene expression that may account for the effects of developmental programming on the timing system. © 2015 by the Society for the Study of Reproduction, Inc.

Biological and socio-cultural factors during the school years predicting women’s lifetime educational attainment

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Hendrick, C. Emily; Cohen, Alison K.; Deardorff, Julianna

2015-01-01

BACKGROUND Lifetime educational attainment is an important predictor of health and well-being for women in the United States. In the current study, we examine the roles of socio-cultural factors in youth and an understudied biological life event, pubertal timing, in predicting women’s lifetime educational attainment. METHODS Using data from the National Longitudinal Survey of Youth 1997 cohort (N = 3889), we conducted sequential multivariate linear regression analyses to investigate the influences of macro-level and family-level socio-cultural contextual factors in youth (region of country, urbanicity, race/ethnicity, year of birth, household composition, mother’s education, mother’s age at first birth) and early menarche, a marker of early pubertal development, on women’s educational attainment after age 24. RESULTS Pubertal timing and all socio-cultural factors in youth, other than year of birth, predicted women’s lifetime educational attainment in bivariate models. Family factors had the strongest associations. When family factors were added to multivariate models, geographic region in youth and pubertal timing were no longer significant. CONCLUSION Our findings provide additional evidence that family factors should be considered when developing comprehensive and inclusive interventions in childhood and adolescence to promote lifetime educational attainment among girls. PMID:26830508

Ethnic differences in body fat distribution among Asian pre-pubertal children: A cross-sectional multicenter study

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Koon Poh Bee

2011-06-01

Full Text Available Abstract Background Ethnic differences in body fat distribution contribute to ethnic differences in cardiovascular morbidities and diabetes. However few data are available on differences in fat distribution in Asian children from various backgrounds. Therefore, the current study aimed to explore ethnic differences in body fat distribution among Asian children from four countries. Methods A total of 758 children aged 8-10 y from China, Lebanon, Malaysia and Thailand were recruited using a non-random purposive sampling approach to enrol children encompassing a wide BMI range. Height, weight, waist circumference (WC, fat mass (FM, derived from total body water [TBW] estimation using the deuterium dilution technique and skinfold thickness (SFT at biceps, triceps, subscapular, supraspinale and medial calf were collected. Results After controlling for height and weight, Chinese and Thai children had a significantly higher WC than their Lebanese and Malay counterparts. Chinese and Thais tended to have higher trunk fat deposits than Lebanese and Malays reflected in trunk SFT, trunk/upper extremity ratio or supraspinale/upper extremity ratio after adjustment for age and total body fat. The subscapular/supraspinale skinfold ratio was lower in Chinese and Thais compared with Lebanese and Malays after correcting for trunk SFT. Conclusions Asian pre-pubertal children from different origins vary in body fat distribution. These results indicate the importance of population-specific WC cut-off points or other fat distribution indices to identify the population at risk of obesity-related health problems.

Effect of Radiation Leakage of Microwave Oven on Rat Serum Testosterone at Pre and Post Pubertal Stage

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Y Zare

2008-01-01

Full Text Available Introduction: Since discovery of high frequency waves, their biological effects have been in great attention. Increased male fertility problems proposed their possible relation to use of microwaves. Testes are of very active body tissues, which can be affected by these waves. Age of exposure may also be an important factor. Methods: This study was carried out to evaluated testosterone level in rats exposed to microwave radiation at pre and post puberty. For this study 18 adult (2 month old and 18 immature (1 month old male rats were selected and each group divided in two groups, control and test group. Test groups were exposed to 2450 MHZ microwaves produced by microwave oven (LG Brant, three times a day, 30 minute each time. Control groups were kept in laboratory at same temperature and light condition. After 60 days blood was collected by heart puncture and testosterone was measured in serum by RIA method. Mean testosterone levels were compared by T-test. Result: The results showed that in immature group testosterone has not changed significantly compare to control group; however in adult group this value was significantly decreased in test group in comparison with control (P<0.005. Conclusion: exposure to microwaves leakage of microwave oven decreased testosterone in adult male rats, which may be due to its direct effect on Leydig cells or indirectly through its effect on pituitary and hypothalamus.

Comparison of the lethal effects of chemical warfare nerve agents across multiple ages.

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Wright, Linnzi K M; Lee, Robyn B; Vincelli, Nicole M; Whalley, Christopher E; Lumley, Lucille A

2016-01-22

Children may be inherently more vulnerable than adults to the lethal effects associated with chemical warfare nerve agent (CWNA) exposure because of their closer proximity to the ground, smaller body mass, higher respiratory rate, increased skin permeability and immature metabolic systems. Unfortunately, there have only been a handful of studies on the effects of CWNA in pediatric animal models, and more research is needed to confirm this hypothesis. Using a stagewise, adaptive dose design, we estimated the 24h median lethal dose for subcutaneous exposure to seven CWNA in both male and female Sprague-Dawley rats at six different developmental times. Perinatal (postnatal day [PND] 7, 14 and 21) and adult (PND 70) rats were more susceptible than pubertal (PND 28 and 42) rats to the lethal effects associated with exposure to tabun, sarin, soman and cyclosarin. Age-related differences in susceptibility were not observed in rats exposed to VM, Russian VX or VX. Published by Elsevier Ireland Ltd.

Subfoveal Choroidal Thickness in 1323 Children Aged 11 to 12 Years and Association With Puberty

DEFF Research Database (Denmark)

Li, Xiao Qiang; Jeppesen, Pia; Larsen, Michael

2014-01-01

.0001). There was no effect of height or puberty in boys, who were less sexually mature than girls. CONCLUSIONS: Choroidal thickness in girls increased with body height and sexual maturation. The results suggest that puberty promotes choroidal thickening in girls, an effect that may be mediated by the pubertal growth spurt....... The lack of pubertal effect in boys may be related to a smaller proportion of boys in this study having entered puberty....

Time-aggregation effects on the baseline of continuous-time and discrete-time hazard models

NARCIS (Netherlands)

ter Hofstede, F.; Wedel, M.

In this study we reinvestigate the effect of time-aggregation for discrete- and continuous-time hazard models. We reanalyze the results of a previous Monte Carlo study by ter Hofstede and Wedel (1998), in which the effects of time-aggregation on the parameter estimates of hazard models were

A longitudinal study of self-control at the transition to secondary school: Considering the role of pubertal status and parenting.

Science.gov (United States)

Ng-Knight, Terry; Shelton, Katherine H; Riglin, Lucy; McManus, I C; Frederickson, Norah; Rice, Frances

2016-07-01

Higher self-control in children and adolescents is associated with a range of positive outcomes in adulthood. However, little is known about the naturalistic development of self-control during early adolescence and the factors that affect this. We examined the role of puberty and parenting style as theoretically important influences on stability and change in self-control. A longitudinal (3 waves), multiple-informant dataset of children entering early adolescence (M = 11 years) was used to explore longitudinal change in self-control using latent growth curve modelling. Children's self-control declined during the one-year study period and declines were associated with children's behavioural and social functioning. Associations with self-control were found for pubertal status and parental warmth and hostility, but not for parental discipline. The findings suggest that during early adolescence, when children make the transition to secondary school, self-control declines. This is particularly the case for those experiencing puberty earlier than their peers. Parent warmth influences the trajectory of self-control during this period. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Effects of dietary exposure to brominated flame retardant BDE-47 on thyroid condition, gonadal development and growth of zebrafish

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Torres, Leticia; Orazio, Carl E.; Peterman, Paul H.; Patino, Reynaldo

2013-01-01

Little is known about the effects of brominated flame retardants in teleosts and some of the information currently available is inconsistent. This study examined effects of dietary exposure to 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) on thyroid condition, body mass and size, and gonadal development of zebrafish. Pubertal, 49-day-old (posthatch) fish were fed diets without BDE-47 (control) or with 1, 5 or 25 μg/g BDE-47/diet. Treatments were conducted in triplicate 30-L tanks each containing 50 zebrafish, and 15 fish per treatment (5 per tank) were sampled at days 40, 80 and 120 of exposure. Measurements were taken of body mass, standard length, head depth and head length. Sex (at 40–120 days of exposure), germ cell stage (at 40 days) and thyroid condition (at 120 days; follicular cell height, colloid depletion, angiogenesis) were histologically determined. Whole-body BDE-47 levels at study completion were within the high end of levels reported in environmentally exposed (wild) fishes. Analysis of variance was used to determine differences among treatments at each sampling time. No effects were observed on thyroid condition or germ cell stage in either sex. Reduced head length was observed in females exposed to BDE-47 at 80 days but not at 40 or 120 days. In males, no apparent effects of BDE-47 were observed at 40 and 80 days, but fish exposed to 25 μg/g had lower body mass at 120 days compared to control fish. These observations suggest that BDE-47 at environmentally relevant whole-body concentrations does not affect thyroid condition or pubertal development of zebrafish but does affect growth during the juvenile-to-adult transition, especially in males.

Effect of estrogens on urinary 15N balance in girls

International Nuclear Information System (INIS)

Zachmann, M.; Kempken, B.; Prader, A.

1984-01-01

While the anabolic and growth-promoting effects of testosterone are known to be important for pubertal growth in boys, the role of estrogens (E) in the female spurt is less certain. Adrenal androgens have been considered to be more important than ovarian E. To study the anabolic effects of E, there has been carried out a pilot study in 9 girls aged 11 to 15 years. Before and 6 days after the start of E treatment, urinary 15 N balance studies were performed, using 15 NH 4 Cl. (author)

7 CFR 922.63 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 922.63 Section 922.63 Agriculture... IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.63 Effective time. The provisions of this part, and of any amendment thereto, shall become effective at such time as the Secretary...

7 CFR 958.70 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 958.70 Section 958.70 Agriculture... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Effective Time and Termination § 958.70 Effective time. The provisions of this subpart, or any amendment thereto, shall become...

7 CFR 948.83 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 948.83 Section 948.83 Agriculture... Order Regulating Handling Miscellaneous Provisions § 948.83 Effective time. The provisions of this subpart or any amendments thereto shall become effective at such time as the Secretary may declare and...

7 CFR 945.82 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 945.82 Section 945.82 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... § 945.82 Effective time. The provisions of this subpart shall become effective at such time as the...

Long-term auxological and pubertal outcome of patients with hereditary insulin-like growth factor-I deficiency (Laron and growth hormone-gene deletion syndrome) treated with recombinant human insulin-like growth factor-I.

Science.gov (United States)

Messina, M F; Arrigo, T; Valenzise, M; Ghizzoni, L; Caruso-Nicoletti, M; Zucchini, S; Chiabotto, P; Crisafulli, G; Zirilli, G; De Luca, F

2011-04-01

GH-IGF-I axis is mainly involved in the complex process of somatic growth but emerging evidence suggests that it also influences hypothalamic-pituitary-gonadal (HPG) function. We report some data regarding long-term auxological and pubertal outcome of five female patients with hereditary forms of GH-IGF-I deficiency (Laron and GH-gene deletion syndrome) and a mean age of 23.4±5.3 yr (range 19-32). All the patients received recombinant human IGF-I (rhIGF-I, Pharmacia and Upjohn, Stockholm, Sweden, and rhIGF-I, Genentech, San Francisco, CA, USA) from a mean age of 8.6 yr (range 3.2-14.2) up to the final height. Final height was very disappointing (≤ -5.0 SD scores) and lower than target height in all the patients. Pubertal onset was delayed in most of them but menarche occurred spontaneously in all the patients. Median age at menarche was 15.1 yr. Menstrual cycles were regular for several years. Median duration of gynecological follow- up was 8.3 yr with the longest span of 17.2 yr. We can assert that GH-IGF-I axis has an essential role in promoting linear growth in humans and its physiological action cannot be replaced by pharmacological treatment in most patients with hereditary forms of IGF-I insufficiency as demonstrated by their subnormal final height. Our clinical observations can also support an essential role of IGF-I in genitalia growth but not in the function of HPG axis as demonstrated by the maintenance of regular menstrual cycles in the presence of subnormal levels of IGF-I after treatment discontinuation.

Effective and Efficient Herbst Appliance Therapy for Skeletal Class II Malocclusion Patient with a Low Degree of Collaboration with the Orthodontic Treatment.

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Souki, Bernardo Quiroga; Bastos, Barbra Duque Costa; Araujo, Luana Fialho Ferro; Moyses-Braga, Wagner Fernando; Pantuzo, Mariele Garcia; Cheib, Paula Loureiro

2015-01-01

The current concept for effective and efficient treatment of skeletal Class II malocclusion prescribes that interceptive approach should be delivered during the pubertal growth stage. However, psychosocial issues and a greater risk of dental trauma are also factors that should be addressed when considering early Class II therapy. This paper reports a case of a patient that sought orthodontic treatment due to aesthetic discomfort with the incisors' protrusion. Two previous treatments failed because patient's collaboration with removable appliances was inadequate. Given his history of no collaboration and because the patient was in the prepubertal stage, it was decided to try a different approach in the third attempt of treatment. Traumatic injury protective devices were used during the prepubertal stage and followed by Herbst appliance and fixed multibrackets therapy during the pubertal stage, resulting in an adequate outcome and long-term stability.

7 CFR 927.77 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 927.77 Section 927.77 Agriculture... Order Regulating Handling Miscellaneous Provisions § 927.77 Effective time. The provisions of this subpart and of any amendment thereto shall become effective at such time as the Secretary may declare, and...

7 CFR 959.83 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 959.83 Section 959.83 Agriculture... Regulating Handling Miscellaneous Provisions § 959.83 Effective time. The provisions of this subpart, or any amendment thereto, shall become effective at such time as the Secretary may declare and shall continue in...

7 CFR 985.71 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 985.71 Section 985.71 Agriculture....71 Effective time. The provisions of this subpart, and of any amendment thereto, shall become effective at such time as the Secretary may declare and shall continue in force until terminated or...

7 CFR 932.67 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 932.67 Section 932.67 Agriculture... Regulating Handling Miscellaneous Provisions § 932.67 Effective time. The provisions of this subpart, as well as any amendments to this subpart, shall become effective at such time as the Secretary may declare...

7 CFR 989.90 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 989.90 Section 989.90 Agriculture... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.90 Effective time. The provisions of this amended subpart, as well as any amendments to this amended subpart shall become effective at such time as...

7 CFR 906.54 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 906.54 Section 906.54 Agriculture... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Miscellaneous Provisions § 906.54 Effective time. The provisions of this subpart, or any amendment thereto, shall become effective at such time as the...

7 CFR 915.63 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 915.63 Section 915.63 Agriculture... Regulating Handling Miscellaneous Provisions § 915.63 Effective time. The provisions of this part shall become effective at such time as the Secretary may declare above his signature to this part, and shall...

7 CFR 917.60 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 917.60 Section 917.60 Agriculture... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.60 Effective time. The provisions of this part and of any amendment thereto, shall become effective at such time as the Secretary may declare...

7 CFR 993.89 - Effective time.

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2010-01-01

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7 CFR 923.63 - Effective time.

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2010-01-01

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7 CFR 966.83 - Effective time.

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2010-01-01

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7 CFR 924.63 - Effective time.

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2010-01-01

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7 CFR 929.68 - Effective time.

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2010-01-01

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7 CFR 983.87 - Effective time.

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2010-01-01

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7 CFR 916.63 - Effective time.

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2010-01-01

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7 CFR 930.82 - Effective time.

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2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 930.82 Section 930.82 Agriculture... Miscellaneous Provisions § 930.82 Effective time. The provisions of this part, and of any amendment thereto, shall become effective at such time as the Secretary may declare, and shall continue in force until...

A common deletion in the uridine diphosphate glucuronyltransferase (UGT) 2B17 gene is a strong determinant of androgen excretion in healthy pubertal boys

DEFF Research Database (Denmark)

Juul, A; Sørensen, K; Aksglaede, L

2008-01-01

2B17 genotypes on urinary excretion of androgen metabolites in pubertal boys. STUDY DESIGN: A clinical study of 116 healthy boys aged 8-19 yr. UGT2B17 genotyping was performed using quantitative PCR. Serum FSH, LH, T, estradiol (E2), and SHBG were analyzed by immunoassays, and urinary levels......BACKGROUND: Testosterone (T) is excreted in urine as water-soluble glucuronidated and sulfated conjugates. The ability to glucuronidate T and other steroids depends on a number of different glucuronidases (UGT) of which UGT2B17 is essential. The aim of the study was to evaluate the influence of UGT...... of androgen metabolites were quantitated by gas chromatography/mass spectrometry in all subjects. RESULTS: Ten of 116 subjects (9%) presented with a homozygote deletion of the UGT2B17 gene (del/del), whereas 52 and 54 boys were hetero- and homozygous carriers of the UGT2B17 gene (del/ins and ins...

Effects of computing time delay on real-time control systems

Science.gov (United States)

Shin, Kang G.; Cui, Xianzhong

1988-01-01

The reliability of a real-time digital control system depends not only on the reliability of the hardware and software used, but also on the speed in executing control algorithms. The latter is due to the negative effects of computing time delay on control system performance. For a given sampling interval, the effects of computing time delay are classified into the delay problem and the loss problem. Analysis of these two problems is presented as a means of evaluating real-time control systems. As an example, both the self-tuning predicted (STP) control and Proportional-Integral-Derivative (PID) control are applied to the problem of tracking robot trajectories, and their respective effects of computing time delay on control performance are comparatively evaluated. For this example, the STP (PID) controller is shown to outperform the PID (STP) controller in coping with the delay (loss) problem.

Effect of estrogens on urinary /sup 15/N balance in girls

Energy Technology Data Exchange (ETDEWEB)

Zachmann, M.; Kempken, B.; Prader, A. (Zurich Univ. (Switzerland))

1984-08-01

While the anabolic and growth-promoting effects of testosterone are known to be important for pubertal growth in boys, the role of estrogens (E) in the female spurt is less certain. Adrenal androgens have been considered to be more important than ovarian E. To study the anabolic effects of E, there has been carried out a pilot study in 9 girls aged 11 to 15 years. Before and 6 days after the start of E treatment, urinary /sup 15/N balance studies were performed, using /sup 15/NH/sub 4/Cl.

Stress during puberty boosts metabolic activation associated with fear-extinction learning in hippocampus, basal amygdala and cingulate cortex.

Science.gov (United States)

Toledo-Rodriguez, Maria; Pitiot, Alain; Paus, Tomáš; Sandi, Carmen

2012-07-01

Adolescence is characterized by major developmental changes that may render the individual vulnerable to stress and the development of psychopathologies in a sex-specific manner. Earlier we reported lower anxiety-like behavior and higher risk-taking and novelty seeking in rats previously exposed to peri-pubertal stress. Here we studied whether peri-pubertal stress affected the acquisition and extinction of fear memories and/or the associated functional engagement of various brain regions, as assessed with 2-deoxyglucose. We showed that while peri-pubertal stress reduced freezing during the acquisition of fear memories (training) in both sexes, it had a sex-specific effect on extinction of these memories. Moreover hippocampus, basal amygdala and cingulate and motor cortices showed higher metabolic rates during extinction in rats exposed to peri-pubertal stress. Interestingly, activation of the infralimbic cortex was negatively correlated with freezing during extinction only in control males, while only males stressed during puberty showed a significant correlation between behavior during extinction and metabolic activation of hippocampus, amygdala and paraventricular nucleus. No correlations between brain activation and behavior during extinction were observed in females (control or stress). These results indicate that exposure to peri-pubertal stress affects behavior and brain metabolism when the individual is exposed to an additional stressful challenge. Some of these effects are sex-specific. Copyright © 2012 Elsevier Inc. All rights reserved.

Improving productivity through more effective time management.

Science.gov (United States)

Arnold, Edwin; Pulich, Marcia

2004-01-01

Effective time management has become increasingly important for managers as they seek to accomplish objectives in today's organizations, which have been restructured for efficiency while employing fewer people. Managers can improve their ability to manage time effectively by examining their attitudes toward time, analyzing time-wasting behaviors, and developing better time management skills. Managers can improve their performance and promotion potential with more effective time utilization. Strategies for improving time management skills are presented.

Blockade of oestrogen biosynthesis in peripubertal boys: effects on lipid metabolism, insulin sensitivity, and body composition.

Science.gov (United States)

Hero, Matti; Ankarberg-Lindgren, Carina; Taskinen, Marja-Riitta; Dunkel, Leo

2006-09-01

In males, the pubertal increase in sex hormone production has been associated with proatherogenic changes in lipid and carbohydrate metabolism. Aromatase inhibitors, a novel treatment modality for some growth disorders, may significantly influence these risk factors for cardiovascular disease by suppressing oestrogen biosynthesis and stimulating gonadal androgen production. In the current study, we explored the effects of aromatase inhibition on lipid metabolism, insulin sensitivity, body composition and serum adiponectin in peripubertal boys. Prospective, double-blind, randomised, placebo-controlled clinical study. Thirty-one boys, aged 9.0-14.5 years, with idiopathic short stature were treated with the aromatase inhibitor letrozole (2.5 mg/day) or placebo for 2 years. During the treatment, the concentrations of sex hormones, IGF-I, lipids, lipoproteins and adiponectin were followed-up. The percentage of fat mass (FM) was assessed by skinfold measurements and insulin resistance by homeostasis model assessment (HOMA) index. In pubertal boys, who received letrozole, high-density lipoprotein cholesterol (HDL-C) decreased by 0.47 mmol/l (P<0.01) during the study. Simultaneously, their percentage of FM decreased from 17.0 to 10.5 (P<0.001), in an inverse relationship with serum testosterone. The concentrations of low-density lipoprotein cholesterol, triglycerides and HOMA index remained at pretreatment level in both groups. Serum adiponectin decreased similarly in letrozole- and placebo-treated pubertal boys (2.9 and 3.3 mg/l respectively). In males, aromatase inhibition reduces HDL-C and decreases relative FM after the start of puberty. The treatment does not adversely affect insulin sensitivity in lean subjects.

Effect of breeding protocols and reproductive tract score on reproductive performance of dairy heifers and economic outcome of breeding programs.

Science.gov (United States)

Stevenson, J L; Rodrigues, J A; Braga, F A; Bitente, S; Dalton, J C; Santos, J E P; Chebel, R C

2008-09-01

The objectives of this study were to evaluate the effect of reproductive protocols and reproductive tract score on reproductive performance of dairy heifers and economic outcomes of breeding programs. Holstein heifers (n = 534), 13 +/- 1 mo of age, were randomly assigned to 1 of 4 reproductive protocols. On the day of enrollment (d 0), heifers were palpated per rectum and received a score according to the maturity of their reproductive tract (1 = prepubertal; 2 = peripubertal; and 3 = puber-tal). Estrous detection-control heifers (CON, n = 146) received no treatment and were inseminated on detection of estrus for 28 d. Prostaglandin F(2alpha)-treated heifers (PGED, n = 137) received 1 injection of PGF(2alpha) on d 0 and were inseminated on detection of estrus; heifers not in-seminated by d 14 received a second injection of PGF(2alpha) and were observed for estrus and artificial insemination (AI) for an additional 14 d. Heifers enrolled in the estrous detection-timed AI (EDTAI, n = 140) treatment received a controlled internal drug-release (CIDR) insert on d 0, and 7 d later, the CIDR was removed and all heifers received an injection of PGF(2alpha), heifers received AI on detection of estrus, and those not inseminated by 72 h after PGF(2alpha) received an injection of GnRH concurrent with AI. Heifers in the GnRH-timed AI (GTAI, n = 111) treatment received 1 injection of GnRH on d 0, on d 6 heifers received a CIDR insert and injections of GnRH and PGF(2alpha), on d 13 the CIDR was removed and heifers received an injection of PGF(2alpha), and 48 h later all heifers received an injection of GnRH and AI. Pregnancy was diagnosed at 32 +/- 3 and 62 +/- 3 d after AI. Cost of reproductive protocols and their economic outcomes were calculated for a 28 d period beginning at enrollment. Heifers in the PGED treatment were inseminated at a faster rate than CON heifers. A smaller proportion of prepubertal and peripubertal heifers were inseminated within 14 d of enrollment

A novel variant of growth hormone (GH) insufficiency following low dose cranial irradiation

Energy Technology Data Exchange (ETDEWEB)

Crowne, E.C.; Moore, C.; Wallace, W.H.B.; Ogilvy-Stuart, A.L.; Addison, G.M.; Morris-Jones, P.H.; Shalet, S.M. (Christie Hospital, Manchester (United Kingdom) Royal Manchester Children' s Hospital (United Kingdom))

1992-01-01

We aimed to investigate the effect of low dose (1800 cGy) prophylactic cranial irradiation on physiological growth hormone secretion. Forty-four children were studied, of whom 21 were long-term survivors of acute lymphoblastic leukaemia and 23 were normal children. In the normal children, there was a significant increase in the median (range) area under the curve (AUC) of the GH profile between the prepubertal and pubertal groups. There was also a change in the spectral analysis through puberty. The dominant frequencies were spread widely in the prepubertal and post-pubertal groups but sharply focused in the pubertal group. In the cranially irradiated children there was no significant increase in AUC between the prepubertal and pubertal groups. The wide range of dominant frequencies persisted in the pubertal cranially irradiated group due to the presence of additional high frequency pulses. The impression of a disturbance of the periodicity of GH secretion in the cranially irradiated pubertal group was further supported by the finding that the autocorrelation function in this group alone was not significantly different from that which would arise from random data. A novel form of GH insufficiency has been observed after low dose irradiation in childhood in which an abnormality of periodicity and a quantitative reduction in GH secretion appears restricted to puberty. (author).

Female Pubertal Timing and Problem Behaviour: The Role of Culture

Science.gov (United States)

Skoog, Therese; Stattin, Hakan; Ruiselova, Zdena; Ozdemir, Metin

2013-01-01

We tested the peer-socialization/contextual-amplification explanation for the link between early female puberty and problem behaviour. We propose that in cultures with high tolerance for adolescent heterosexual involvement, early puberty should be linked with problem behaviour--not in other cultures. We compared girls in two cultures (Slovakia and…

High Times: The Effect of Medical Marijuana Laws on Student Time Use

OpenAIRE

Chu, Yu-Wei Luke; Gershenson, Seth

2016-01-01

Twenty-three states and the District of Columbia have passed medical marijuana laws. Previous research shows that these laws increase marijuana use among adults. In this paper, we estimate the effects of medical marijuana laws (MML) on secondary and post-secondary students' time use using time diaries from the American Time Use Survey. We apply a difference-in-differences research design and estimate flexible fixed effects models that condition on state fixed effects and state-specific time t...

Quantificação de esteróides fecais de fêmeas de onça-pintada (Panthera onca mantidas em cativeiro: validação da técnica

Directory of Open Access Journals (Sweden)

Priscila Viau

2005-08-01

Full Text Available Ovarian function of captive jaguars (Panthera onca; adults n=2 and pre-pubertal n=3 was assessed by extraction and quantification of fecal estrogens and progestins. Fecal samples were obtained 2-7 times per week during 16-18 months. Validation of solid phase radioimmunoassay for progesterone and 17b-estradiol was performed for jaguar fecal extracts. Mean concentration the fecal estrogen (ng/g of dry feces in pre-pubertal animals was 10,97 (range, 0,28 - 59,16 and adults animals was 68,99 (range, 3,50 - 609,37. Fecal progestins (mg/g of dry feces had a mean concentration of 0,26 (range, 0,02 - 4,44 in pre-pubertal animals and adults animals was 0,85 (range, 0,08 - 6,51.

The relationship between puberty and social emotion processing

Science.gov (United States)

Goddings, Anne-Lise; Burnett Heyes, Stephanie; Bird, Geoffrey; Viner, Russell M; Blakemore, Sarah-Jayne

2012-01-01

The social brain undergoes developmental change during adolescence, and pubertal hormones are hypothesized to contribute to this development. We used fMRI to explore how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to brain activity during a social emotion task. Forty-two females aged 11.1 to 13.7 years underwent fMRI scanning while reading scenarios pertaining either to social emotions, which require the representation of another person’s mental states, or to basic emotions, which do not. Pubertal stage and menarcheal status were used to assign girls to early or late puberty groups. Across the entire sample, the contrast between social versus basic emotion resulted in activity within the social brain network, including dorsomedial prefrontal cortex (DMPFC), the posterior superior temporal sulcus, and the anterior temporal cortex (ATC) in both hemispheres. Increased hormone levels (independent of age) were associated with higher left ATC activity during social emotion processing. More advanced age (independent of hormone levels) was associated with lower DMPFC activity during social emotion processing. Our results suggest functionally dissociable effects of pubertal hormones and age on the adolescent social brain. PMID:23106734

Isolated torsion of the fallopian tube in a menopausal woman and a pre-pubertal girl: two case reports.

Science.gov (United States)

Toyoshima, Masafumi; Mori, Hikaru; Kudo, Kei; Yodogawa, Yuki; Sato, Kazuyo; Kudo, Takako; Igeta, Saori; Makino, Hiromitsu; Shima, Takashi; Matsuura, Rui; Ishigaki, Nobuko; Akagi, Kozo; Takeyama, Yoichi; Iwahashi, Hideki; Yoshinaga, Kosuke

2015-11-17

Isolated torsion of the fallopian tube without an ovarian abnormality is an uncommon event, with an incidence of approximately 1 in 1,500,000 females. Isolated torsion of the fallopian tube occurs mostly in reproductive-aged women, and is thus extremely rare in menopausal women and pre-pubertal girls. In case 1, 63-year-old Japanese woman presented with a 2-day history of acute lower abdominal pain. Menopause occurred at 53 years of age. Pelvic ultrasonography showed an enlarged mass (73 × 47 mm) on the right side of her uterus. An urgent laparoscopy was performed based on a presumptive diagnosis of right ovarian tumor torsion. During the laparoscopy, we noted a black, necrotic, solid tumor arising from the distal end of her right fimbria. Her right fallopian tube was twisted with the tumor, but her right ovary was normal and not involved. A laparoscopic tumorectomy with a right salpingectomy was performed. Her post-operative course was uneventful. In case 2, a 10-year-old Japanese girl presented with a 1-day history of lower abdominal pain associated with nausea and vomiting. Menarche had occurred 2 months earlier. A computed tomography and magnetic resonance imaging examination demonstrated a dilated tubal cystic mass with a normal uterus and bilateral ovaries. An urgent laparoscopy was performed based on a presumptive diagnosis of right fallopian tube torsion. During laparoscopy, her right fallopian tube was noted to be dark red, dilated, and twisted several times. Her right fimbria was necrotic-appearing and could not be preserved. Therefore, a laparoscopic right salpingectomy was performed. A histologic examination revealed ischemic changes with congestion of her right fallopian tube, which was consistent with tubal torsion. She had an uncomplicated post-operative course. We have presented two very rare cases of isolated fallopian tubal torsion. Radiologic interventions, such as computed tomography and magnetic resonance imaging, in addition to

Effective time management – selected issues

Directory of Open Access Journals (Sweden)

Aneta Olejniczak

2013-03-01

Full Text Available Deliberations included in this article contain the basic issues related to the subject of time management. As we know, people who waste their time the most, most complain about the lack of the time. We should treat our time, time of our co-workers, and friends as a valuable, but limited wealth. Principles of effective time management can be applied in any scientific and research institutions, companies or corporations. The benefits of a good and effective time management will be felt not only by ourselves but also by our friends and family. Detailed formulation of objectives, identification and elimination of time wasters and postponing work on later (Procrastination, using methods of time management and systematic control will allow for efficient use of time. A good plan is the basis for optimal and meaningful use of time.

Gender differentiations of cognitive-motor functioning in prepubertal and pubertal children.

Science.gov (United States)

Katić, Ratko; Bala, Gustav; Barović, Zdenka

2012-06-01

The aim of this study was to determine cognitive and motor status factors in female and male children aged 10-14, as well as developmental and/or integration functions according to gender. The study included 162 girls and 134 boys aged 10-14, divided into four groups: 84 girls aged 10-12 (mean age 11.26, SD 0.68), 84 boys aged 10-12 (mean age 11.41, SD 0.50), 78 girls aged 13-14 (mean age 13.52, SD 0.63) and 50 boys aged 13-14 (mean age 13.21, SD 0.53). The significance of quantitative differences between boys and girls in the overall system of variables was defined based on the results of canonic discriminant analysis of variance, and within each variable based on the results on univariate analysis of variance (ANOVA). In the younger age group (10-12 years), girls were superior to boys in a test assessing flexibility (Seated straddle stretch), whereas, compared to girls, boys had greater strength of the trunk (Crossed-arm sit-ups), greater explosive strength ofjump and sprint type (Standing broad jump and 20 m dash), and coordination (Obstacle course backwards and Steps laterally). In the older age group (13-14 years) differences in flexibility were even more prominent in favor of girls, whereas the differences in explosive strength increased in favor of boys, especially of the throwing type with better agility (Steps laterally), balance (Board balance) and greater static strength of arms and shoulders (Bent-arm hang). In order to determine qualitative differences between pubertal and prepubertal girls and boys, the matrix of variable inter-correlations was factorized by the procedure of principal components procedure, that were then transformed to promax solution. The results showed that cognitive functioning had a significant role in the motor efficacy of girls and boys aged 10 to 14. In the age group of 10-12 years, in females, cognitive functioning is related to the motor system which integrates the regulation of muscle tone with agility/coordination, whereas

Early Puberty, Friendship Group Characteristics, and Dating Abuse in US Girls.

Science.gov (United States)

Chen, Frances R; Rothman, Emily F; Jaffee, Sara R

2017-06-01

The current study aimed to investigate the relationship between advanced pubertal development and adolescent dating abuse (ADA) and to test if this relationship is moderated by friendship group characteristics in a nationally representative sample of US girls. Data were drawn from wave 1 and 2 (1995-1996) of the National Longitudinal Study of Adolescent to Adult Health. The sample included 3870 girls aged 13 to 17 years, all of whom were in romantic and/or nonromantic sexual relationships. Relative pubertal development was measured as perceived physical development as compared with peers of the same age and race and age at menarche at wave 1. Participants reported at wave 2 whether they had experienced any verbal or physical abuse in their relationships. Friendship group characteristics included the percentage of boy friends, older friends, and friends' risk behavior level. Negative binomial regression analyses revealed an interaction between advanced pubertal development and percentage of boy friends on ADA victimization, adjusted for age, race, parents' marital status, household income, number of relationships, self-esteem, self-control, and antisocial behavior history. Advanced pubertal development was associated with more ADA victimization when girls' friendship groups comprised a higher percentage of boys. Findings highlight the importance of pubertal timing and friendship group characteristics to ADA victimization. Early pubertal development is a risk marker for ADA victimization, particularly when a higher percentage of girls' friends are boys. Pediatricians and adolescent health specialists should be sensitive to the elevated risk for ADA victimization in early-maturing girls. Copyright © 2017 by the American Academy of Pediatrics.

7 CFR 905.82 - Effective time.

Science.gov (United States)

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 905.82 Section 905.82 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... TANGELOS GROWN IN FLORIDA Order Regulating Handling Miscellaneous Provisions § 905.82 Effective time. The...

7 CFR 996.75 - Effective time.

Science.gov (United States)

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Effective time. 996.75 Section 996.75 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Effective time. The provisions of this part, as well as any amendments, shall apply to 2003-04 and...

Binge-pattern alcohol exposure during puberty induces long-term changes in HPA axis reactivity.

Directory of Open Access Journals (Sweden)

Magdalena M Przybycien-Szymanska

2011-04-01

Full Text Available Adolescence is a dynamic and important period of brain development however, little is known about the long-term neurobiological consequences of alcohol consumption during puberty. Our previous studies showed that binge-pattern ethanol (EtOH treatment during pubertal development negatively dysregulated the responsiveness of the hypothalamo-pituitary-adrenal (HPA axis, as manifested by alterations in corticotrophin-releasing hormone (CRH, arginine vasopressin (AVP, and corticosterone (CORT during this time period. Thus, the primary goal of this study was to determine whether these observed changes in important central regulators of the stress response were permanent or transient. In this study, juvenile male Wistar rats were treated with a binge-pattern EtOH treatment paradigm or saline alone for 8 days. The animals were left undisturbed until adulthood when they received a second round of treatments consisting of saline alone, a single dose of EtOH, or a second binge-pattern treatment paradigm. The results showed that pubertal binge-pattern EtOH exposure induced striking long-lasting alterations of many HPA axis parameters. Overall, our data provide strong evidence that binge-pattern EtOH exposure during pubertal maturation has long-term detrimental effects for the healthy development of the HPA axis.

Influence of Deficiency or Supplementary Selenium and a- Tochopherol (Vitamin E) In The Diet of Pubertal Male Zaraibi Goats on Fertility, Semen Quality and Testicular Traits

International Nuclear Information System (INIS)

Habeeb, A.A.M.; Teama, F.E.I.

2013-01-01

Twenty pubertal male Zaraibi goats (bucks) were randomly divided into four equal groups; fed deficient Se or vit. E, adequate Se, adequate vit. E and adequate Se + vit. E diets for 3 months to study the influence of deficient or adequate selenium (Se) and vitamin E (vit. E) in the diet of pubertal male Zaraibi goats on fertility, semen quantity and quality and some testicular traits. The results showed that the best values of semen quantity (the ejaculate volume, sperm concentration and total sperm output per ejaculate) and semen quality (percentage of progressive motility, percentage of live sperm, number of motile sperm per ejaculate, percentage of dead, abnormal spermatozoa and acrosomal abnormality) were observed in bucks fed diet supplemented with adequate Se combined with adequate vit. E. The lowest values of semen quantity and semen quality were observed in bucks suffering from deficiency of Se and/or vit. E in their diets. Testosterone level in seminal plasma was significantly higher in bucks fed adequate Se and/or vit. E than those fed diet deficient in Se and vit. E. Testosterone level was significantly higher in bucks fed diet adequate in Se + vit. E than those fed diet adequate with Se or vit. E alone. Se and vit. E deficiency in the diets was accompanied by a significant decrease in testosterone, T 4 and T 3 levels in seminal plasma. Selenium or vit. E each one alone supplementation led to increases of these hormones. T 4 and T 3 levels were significantly higher in bucks fed adequate Se or adequate Se + vit. E than in bucks fed diet with adequate vitamin E alone. Adequate Se alone and adequate Se + vit. E diets were accompanied by significant increases in Se in seminal plasma. Adequate vit. E and adequate Se + vit. E diets were accompanied by significant increase in vit. E level in the seminal plasma. It is clear that there was synergism between Se and vit. E in the biological role of Se, since the level of Se in bucks fed diet containing adequate Se

The effects of oestrogens on linear bone growth

DEFF Research Database (Denmark)

Juul, A

2001-01-01

Regulation of linear bone growth in children and adolescents comprises a complex interaction of hormones and growth factors. Growth hormone (GH) is considered to be the key hormone regulator of linear growth in childhood. The pubertal increase in growth velocity associated with GH has traditionally...... been attributed to testicular androgen secretion in boys, and to oestrogens or adrenal androgen secretion in girls. Research data indicating that oestrogen may be the principal hormone stimulating the pubertal growth spurt in boys as well as girls is reviewed. Such an action is mediated by oestrogen...... female growth spurt despite lack of androgen action. Oestrogens may also influence linear bone growth indirectly via modulation of the GH-insulin-like growth factor-I (IGF-I) axis. Thus, ER blockade diminishes endogenous GH secretion, androgen receptor (AR) blockade increases GH secretion in peripubertal...

Environmental factors and puberty timing: expert panel research needs

DEFF Research Database (Denmark)

Louis, G.M. Buck; Jr, L.E. Gray; Marcus, M.

2008-01-01

initiatives include (1) etiologic research that focus on environmentally relevant levels of endocrine-disrupting chemicals and body size in relation to normal puberty as well as its variants, (2) exposure assessment of relevant endocrine-disrupting chemicals during critical windows of human development......, body size, and puberty. The panel concluded that available experimental animal and human data support a possible role of endocrine-disrupting chemicals and body size in relation to alterations in pubertal onset and progression in boys and girls. Critical data gaps prioritized for future research...

A good time to leave?: the sunk time effect in pigeons.

Science.gov (United States)

Magalhães, Paula; White, K Geoffrey

2014-06-01

Persistence in a losing course of action due to prior investments of time, known as the sunk time effect, has seldom been studied in nonhuman animals. On every trial in the present study, pigeons were required to choose between two response keys. Responses on one key produced food after a short fixed interval (FI) of time on some trials, or on other trials, no food (Extinction) after a longer time. FI and Extinction trials were not differently signaled, were equiprobable, and alternated randomly. Responses on a second Escape key allowed the pigeon to terminate the current trial and start a new one. The optimal behavior was for pigeons to peck the escape key once the duration equivalent to the short FI had elapsed without reward. Durations of the short FI and the longer Extinction schedules were varied over conditions. In some conditions, the pigeons suboptimally responded through the Extinction interval, thus committing the sunk time effect. The absolute duration of the short FI had no effect on the choice between persisting and escaping. Instead, the ratio of FI and Extinction durations determined the likelihood of persistence during extinction. Copyright © 2014 Elsevier B.V. All rights reserved.

Non-carcinogenic late effects of ionizing radiation; human data

International Nuclear Information System (INIS)

Beebe, G.W.

1979-01-01

The late effects of ionizing radiation may be somatic effect or potential effect, about which such informations as follows are required: teratogenesis the disturbances in growth and development, cataracts, infertility, cytogenetic aberration, and accelerated aging. Although much is known about the nature of the malformations produced by ionizing radiation, and about the vulnerability of human embryonal and fetal tissues during various stages of organogenesis, the quantitative information is uncertain and incomplete. The data on A-bomb survivors were flawed by confounding radiation dose with nutritional and other influences caused by the disasters created by war-time bombings. If the effects of radiation are real, they are quite small for the dose below 100 rad (kerma), are confined to the children of pre-pubertal age at the time of exposure, and are of much less consequence for low-LET radiation than for high. Radiation-induced lenticular changes are of graded severity, and as for cataracts, the threshold is in the range from 600 to 1,000 rad of low-LET radiation, and perhaps 75 to 100 rad for fast neutrons; the average latent period is 2 to 7 years. The estimate of the RBE for neutrons is in the range from 2 to 10, and dose-dependent. Ionizing radiation has important effects on fertility only at very high dose. The relationship of the quantitative aspects of the biologic significance of chromosomal aberration in somatic cells to dose may provide an interesting parallel to the carcinogenic effect. For neutrons, the dose-response curve appears to be linear, at least for stable aberration. (Yamashita, S.)

Elevated serum levels of free triiodothyronine in adolescent boys with gynaecomastia compared with controls

DEFF Research Database (Denmark)

Mieritz, Mikkel G; Sørensen, Kaspar; Aksglæde, Lise

2014-01-01

OBJECTIVE: Pubertal gynaecomastia is a frequent phenomenon occurring in 20-40% of otherwise healthy adolescent boys. Little is known about the aetiology of pubertal gynaecomastia. Markedly elevated thyroid hormone levels in adults with hyperthyroidism are associated with gynaecomastia. DESIGN......: A cross-sectional examination of 444 healthy boys with and without pubertal gynaecomastia. METHODS: We evaluated TSH, triiodothyronine (T3), thyroxine (T4), free T4 and free T3 in a cohort of healthy boys with and without pubertal gynaecomastia. RESULTS: Boys with gynaecomastia had significantly higher...... of pubertal gynaecomastia....

Effects of prenatal exposure to a low dose atrazine metabolite mixture on pubertal timing and prostate development of male Long-Evans rats

Energy Technology Data Exchange (ETDEWEB)

Stanko, Jason [National Institute of Environmental Health Sciences (NIEHS); Enoch, Rolondo [North Carolina Central University, Durham; Rayner, Jennifer L [ORNL; Davis, Christine [U.S. Environmental Protection Agency; Wolf, Douglas [U.S. Environmental Protection Agency; Malarkey, David [University of North Carolina, Chapel Hill; Fenton, Suzanne [National Institute of Environmental Health Sciences (NIEHS)

2010-12-01

The present study examines the postnatal reproductive development of male rats following prenatal exposure to an atrazine metabolite mixture (AMM) consisting of the herbicide atrazine and its environmental metabolites diaminochlorotriazine, hydroxyatrazine, deethylatrazine, and deisopropylatrazine. Pregnant Long-Evans rats were treated by gavage with 0.09, 0.87, or 8.73 mg AMM/kg body weight (BW), vehicle, or 100 mg ATR/kg BW positive control, on gestation days 15 19. Preputial separation was significantly delayed in 0.87 mg and 8.73 mg AMM-exposed males. AMM-exposed males demonstrated a significant treatment-related increase in incidence and severity of inflammation in the prostate on postnatal day (PND) 120. A dose-dependent increase in epididymal fat masses and prostate foci were grossly visible in AMM-exposed offspring. These results indicate that a short, late prenatal exposure to mixture of chlorotriazine metabolites can cause chronic prostatitis in male LE rats. The mode of action for these effects is presently unclear.

An approach to constitutional delay of growth and puberty

Directory of Open Access Journals (Sweden)

Ashraf T Soliman

2012-01-01

Full Text Available Constitutional delay of growth and puberty is a transient state of hypogonadotropic hypogonadism associated with prolongation of childhood phase of growth, delayed skeletal maturation, delayed and attenuated pubertal growth spurt, and relatively low insulin-like growth factor-1 secretion. In a considerable number of cases, the final adult height (Ht does not reach the mid-parental or the predicted adult Ht for the individual, with some degree of disproportionately short trunk. In the pre-pubertal male, testosterone (T replacement therapy can be used to induce pubertal development, accelerate growth and relieve the psychosocial complaints of the adolescents. However, some issues in the management are still unresolved. These include type, optimal timing, dose and duration of sex steroid treatment and the possible use of adjunctive or alternate therapy including: oxandrolone, aromatase inhibitors and human growth hormone.

The effects of Aloe vera [gel] on clotting time, prothrombin time and ...

African Journals Online (AJOL)

Background: Published reports on the effects of Aloe vera gel on blood coagulation in experimental animals are relatively scanty. Aim: To determine the effect of Aloe vera gel on clotting time, prothrombin time and plasma fibrinogen concentration in albino Wistar rats. Methods: A total of 28 adult albino Wistar rats divided ...

South Carolina Cancer Health Equity Consortium: HBCU Student Summer Training Program

Science.gov (United States)

2017-08-01

term effects on our health when we get much older . The accumulation of AGEs alters the development of the pubertal mammary gland by increasing cell...Papilloma Virus (HPV) is a sexually transmitted virus that is associated with cervical cancer. HPV early proteins, E6 and E7, have cancer-killing...The Impact of Reactive Sugar Metabolites on Pubertal Mammary Gland Development and Increased Cancer Risk Advanced Glycation End-Products ( AGEs ) are a

Timing effects on first marriage

DEFF Research Database (Denmark)

Schoen, Robert; Canudas-Romo, Vladimir

2005-01-01

Recent substantial declines in first marriage in Western countries have been accompanied by increases in the average age at first marriage. Since the period proportion ever marrying, PEM, is sensitive to cohort tempo changes, the recent fall in the PEM may simply reflect cohort delays in marriage....... The importance of timing factors is examined in the light of twentieth-century experience of first marriage in England and Wales and the USA. Using a variant of the Timing Index developed in research on fertility, we measure cohort timing effects for marriage and calculate an adjusted PEM. After examining...... twentieth-century trends in nuptiality for men and women, we find substantial tempo effects on the period PEM. Adjusted PEM values show a real decline in marriage for cohorts, but that decline is considerably smaller than the one shown by the unadjusted figures. This is especially true for England and Wales...

Time to work or time to play: the effect of student employment on homework, sleep, and screen time

OpenAIRE

Kalenkoski, Charlene Marie; Wulff Pabilonia, Sabrina

2009-01-01

We use detailed time-diary information on high school students’ daily activities from the 2003–2008 American Time Use Surveys (ATUS) to investigate the effects of employment on the time a student spends on homework and other major activities. Time-diary data are more detailed and accurate than data derived from responses to “usual activity” survey questions underlying other analyses and capture the immediate effects of working that may well accumulate over time to affect future outcomes. Our ...

Defining a novel leptin–melanocortin–kisspeptin pathway involved in the metabolic control of puberty

Directory of Open Access Journals (Sweden)

Maria Manfredi-Lozano

2016-10-01

Full Text Available Objective: Puberty is a key developmental phenomenon highly sensitive to metabolic modulation. Worrying trends of changes in the timing of puberty have been reported in humans. These might be linked to the escalating prevalence of childhood obesity and could have deleterious impacts on later (cardio-metabolic health, but their underlying mechanisms remain unsolved. The neuropeptide α-MSH, made by POMC neurons, plays a key role in energy homeostasis by mediating the actions of leptin and likely participates in the control of reproduction. However, its role in the metabolic regulation of puberty and interplay with kisspeptin, an essential puberty-regulating neuropeptide encoded by Kiss1, remain largely unknown. We aim here to unveil the potential contribution of central α-MSH signaling in the metabolic control of puberty by addressing its role in mediating the pubertal effects of leptin and its potential interaction with kisspeptin. Methods: Using wild type and genetically modified rodent models, we implemented pharmacological studies, expression analyses, electrophysiological recordings, and virogenetic approaches involving DREADD technology to selectively inhibit Kiss1 neurons, in order to interrogate the physiological role of a putative leptin→α-MSH→kisspeptin pathway in the metabolic control of puberty. Results: Stimulation of central α-MSH signaling robustly activated the reproductive axis in pubertal rats, whereas chronic inhibition of melanocortin receptors MC3/4R, delayed puberty, and prevented the permissive effect of leptin on puberty onset. Central blockade of MC3/4R or genetic elimination of kisspeptin receptors from POMC neurons did not affect kisspeptin effects. Conversely, congenital ablation of kisspeptin receptors or inducible, DREADD-mediated inhibition of arcuate nucleus (ARC Kiss1 neurons resulted in markedly attenuated gonadotropic responses to MC3/4R activation. Furthermore, close appositions were observed between

Effective Feature Preprocessing for Time Series Forecasting

DEFF Research Database (Denmark)

Zhao, Junhua; Dong, Zhaoyang; Xu, Zhao

2006-01-01

Time series forecasting is an important area in data mining research. Feature preprocessing techniques have significant influence on forecasting accuracy, therefore are essential in a forecasting model. Although several feature preprocessing techniques have been applied in time series forecasting...... performance in time series forecasting. It is demonstrated in our experiment that, effective feature preprocessing can significantly enhance forecasting accuracy. This research can be a useful guidance for researchers on effectively selecting feature preprocessing techniques and integrating them with time...... series forecasting models....

Effective time-independent analysis for quantum kicked systems

Science.gov (United States)

Bandyopadhyay, Jayendra N.; Guha Sarkar, Tapomoy

2015-03-01

We present a mapping of potentially chaotic time-dependent quantum kicked systems to an equivalent approximate effective time-independent scenario, whereby the system is rendered integrable. The time evolution is factorized into an initial kick, followed by an evolution dictated by a time-independent Hamiltonian and a final kick. This method is applied to the kicked top model. The effective time-independent Hamiltonian thus obtained does not suffer from spurious divergences encountered if the traditional Baker-Cambell-Hausdorff treatment is used. The quasienergy spectrum of the Floquet operator is found to be in excellent agreement with the energy levels of the effective Hamiltonian for a wide range of system parameters. The density of states for the effective system exhibits sharp peaklike features, pointing towards quantum criticality. The dynamics in the classical limit of the integrable effective Hamiltonian shows remarkable agreement with the nonintegrable map corresponding to the actual time-dependent system in the nonchaotic regime. This suggests that the effective Hamiltonian serves as a substitute for the actual system in the nonchaotic regime at both the quantum and classical level.

Self-reported screen time and cardiometabolic risk in obese Dutch adolescents.

Directory of Open Access Journals (Sweden)

Teatske M Altenburg

Full Text Available BACKGROUND: It is not clear whether the association between sedentary time and cardiometabolic risk exists among obese adolescents. We examined the association between screen time (TV and computer time and cardiometabolic risk in obese Dutch adolescents. METHODS AND FINDINGS: For the current cross-sectional study, baseline data of 125 Dutch overweight and obese adolescents (12-18 years participating in the Go4it study were included. Self-reported screen time (Activity Questionnaire for Adolescents and Adults and clustered and individual cardiometabolic risk (i.e. body composition, systolic and diastolic blood pressure, low-density (LDL-C, high-density (HDL-C and total cholesterol (TC, triglycerides, glucose and insulin were assessed in all participants. Multiple linear regression analyses were used to assess the association between screen time and cardiometabolic risk, adjusting for age, gender, pubertal stage, ethnicity and moderate-to-vigorous physical activity. We found no significant relationship between self-reported total screen time and clustered cardiometabolic risk or individual risk factors in overweight and obese adolescents. Unexpectedly, self-reported computer time, but not TV time, was slightly but significantly inversely associated with TC (B = -0.002; CI = [-0.003;-0.000] and LDL-C (B = -0.002; CI = [-0.001;0.000]. CONCLUSIONS: In obese adolescents we could not confirm the hypothesised positive association between screen time and cardiometabolic risk. Future studies should consider computer use as a separate class of screen behaviour, thereby also discriminating between active video gaming and other computer activities.

Extrapolation of experimental data on late effects of low-dose radionuclides in man

International Nuclear Information System (INIS)

Kalistratova, V.S.; Nisimov, P.G.

1997-01-01

The situation of living of population on radionuclide contamination areas was simulated in the experimental study using white strainless rats of different ages. The significance of age for late stochastic effects of internal radionuclide contamination with low doses of 131 I, 137 Cs, 144 Ce and 106 Ru was studied. Some common regularities and differences in late effects formation depending on age were found. Results of the study showed that the number of tumors developed increased in groups of animals exposed at the youngest age. The younger animal at the moment of internal radionuclide contamination, the higher percentage of malignant tumors appeared. It was especially so for tumors of endocrine glands (pituitary, suprarenal,- and thyroid). Differences in late effects formation related to different type of radionuclide distribution within the body were estimated. On the base of extrapolation the conclusion was made that human organism being exposed at early postnatal or pubertal period could be the most radiosensitive (1.5-2.0 or sometimes even 3-5 times higher than adults). Data confirmed the opinion that children are the most critical part of population even in case of low dose radiation exposure. (author)

The Effect of Metformine on Glucose Control in Patients with Diabetes Type 1

Directory of Open Access Journals (Sweden)

A. Ziaee

2010-07-01

Full Text Available Introduction & Objective: Metabolic control in adolescents with type 1 DM who are in pubertal period will be impaired, thus finding a therapeutic strategy such as adding metformin to insulin to reduce insulin resistance will be useful in blood glucose control and metabolic state improvement.Materials & Methods: This was a randomized double blind placebo controlled 3-month trial metformin therapy in 32 adolescents with type 1 DM. These patients were divided in two groups of metformin and placebo and treated with metformin and placebo for 3-months. Their HbA1C, FBS, Insulin dosage, TG, Cholesterol, and LDL were measured at the initiation and end of the treatment.Results: After the study there was a significant improvement of FBS and TG in metformin group versus placebo group (P=0.02 and P=0.028 in order. But, there was not significant difference in other variables such as BMI, insulin dosage, HbA1C, Cholesterol and LDL between the two groups.Conclusion: Metformin treatment in teenagers with type1 DM who are in pubertal period will improve the control of FBS and lowers TG but has not any significant effect on HbA1C, BMI, insulin dosage, Cholesterol and LDL.

Gene expression during testis development in Duroc boars

DEFF Research Database (Denmark)

Lervik, Siri; Kristoffersen, Anja Bråthen; Conley, Lene

2015-01-01

. Nine clusters of genes with significant differential expression over time and 49 functional charts were found in the analysed testis samples. Prominent pathways in the prepubertal testis were associated with tissue renewal, cell respiration and increased endocytocis. E-cadherines may be associated...... with the onset of pubertal development. With elevated steroidogenesis (weeks 16 to 27), there was an increase in the expression of genes in the MAPK pathway, STAR and its analogue STARD6. A pubertal shift in genes coding for cellular cholesterol transport was observed. Increased expression of meiotic pathways...

Alcohol alters hypothalamic glial-neuronal communications involved in the neuroendocrine control of puberty: In vivo and in vitro assessments.

Science.gov (United States)

Dees, W L; Hiney, J K; Srivastava, V K

2015-11-01

The onset of puberty is the result of the increased secretion of hypothalamic luteinizing hormone-releasing hormone (LHRH). The pubertal process can be altered by substances that can affect the prepubertal secretion of this peptide. Alcohol is one such substance known to diminish LHRH secretion and delay the initiation of puberty. The increased secretion of LHRH that normally occurs at the time of puberty is due to a decrease of inhibitory tone that prevails prior to the onset of puberty, as well as an enhanced development of excitatory inputs to the LHRH secretory system. Additionally, it has become increasingly clear that glial-neuronal communications are important for pubertal development because they play an integral role in facilitating the pubertal rise in LHRH secretion. Thus, in recent years attempts have been made to identify specific glial-derived components that contribute to the development of coordinated communication networks between glia and LHRH cell bodies, as well as their nerve terminals. Transforming growth factor-α and transforming growth factor-β1 are two such glial substances that have received attention in this regard. This review summarizes the use of multiple neuroendocrine research techniques employed to assess these glial-neuronal communication pathways involved in regulating prepubertal LHRH secretion and the effects that alcohol can have on their respective functions. Copyright © 2015 Elsevier Inc. All rights reserved.

Toxicological assessment of drugs that affect the endocrine system in puberty-related disorders.

Science.gov (United States)

Maranghi, Francesca; Tassinari, Roberta; Mantovani, Alberto

2013-10-01

Toxicologists must ensure that clinical risk-to-benefit analysis should be made both for genders and age groups, with any treatment. Puberty concerns physiological changes leading to organism's maturation. Pubertal growth disorders are increasing in last decades: besides causing physical and psychological distress, they may signal underlying endocrine-metabolic abnormalities with serious health consequences later on. Therapeutic approaches for some health conditions in childhood and adolescence are considered. The authors discuss how some diseases and treatments can impact pubertal growth. The authors look at particular immunological disorders such as asthma and how both the disease and treatment affects pubertal growth. They also discuss how the provision of available data can help to assess the dose-response of the drug, in these cases, and minimize the chance of side effects. The authors also discuss pediatric inflammatory bowel disease and how both the disease and treatment can mitigate the growth delay. Last, but not least, the authors discuss how the effects of the drugs used in the treatment of psychiatric disorders may accentuate endocrine issues in juvenile patients. Hyperprolactinemia induction by some antipsychotics is highlighted as an example. Appropriate risk-benefit analysis of drugs prescribed during childhood and adolescence and intended to be used in the long term is required. Furthermore, future treatment strategies and safer compounds development should be supported by the knowledge of mechanisms underlying adverse side effects in pubertal growth and development.

Genetic and environmental influences on thin-ideal internalization across puberty and preadolescent, adolescent, and young adult development.

Science.gov (United States)

Suisman, Jessica L; Thompson, J Kevin; Keel, Pamela K; Burt, S Alexandra; Neale, Michael; Boker, Steven; Sisk, Cheryl; Klump, Kelly L

2014-11-01

Mean-levels of thin-ideal internalization increase during adolescence and pubertal development, but it is unknown whether these phenotypic changes correspond to developmental changes in etiological (i.e., genetic and environmental) risk. Given the limited knowledge on risk for thin-ideal internalization, research is needed to guide the identification of specific types of risk factors during critical developmental periods. The present twin study examined genetic and environmental influences on thin-ideal internalization across adolescent and pubertal development. Participants were 1,064 female twins (ages 8-25 years) from the Michigan State University Twin Registry. Thin-ideal internalization and pubertal development were assessed using self-report questionnaires. Twin moderation models were used to examine if age and/or pubertal development moderate genetic and environmental influences on thin-ideal internalization. Phenotypic analyses indicated significant increases in thin-ideal internalization across age and pubertal development. Twin models suggested no significant differences in etiologic effects across development. Nonshared environmental influences were most important in the etiology of thin-ideal internalization, with genetic, shared environmental, and nonshared environmental accounting for approximately 8%, 15%, and 72%, respectively, of the total variance. Despite mean-level increases in thin-ideal internalization across development, the relative influence of genetic versus environmental risk did not differ significantly across age or pubertal groups. The majority of variance in thin-ideal internalization was accounted for by environmental factors, suggesting that mean-level increases in thin-ideal internalization may reflect increases in the magnitude/strength of environmental risk across this period. Replication is needed, particularly with longitudinal designs that assess thin-ideal internalization across key developmental phases. © 2014 Wiley

Timely and Effective Care - Hospital

Data.gov (United States)

U.S. Department of Health & Human Services — Timely and Effective Care measures - provider data. This data set includes provider-level data for measures of cataract surgery outcome, colonoscopy follow-up, heart...

Timely and Effective Care - State

Data.gov (United States)

U.S. Department of Health & Human Services — Timely and Effective Care measures - provider data. This data set includes state-level data for measures of cataract surgery outcome, colonoscopy follow-up, heart...

Timely and Effective Care - National

Data.gov (United States)

U.S. Department of Health & Human Services — Timely and Effective Care measures - provider data. This data set includes national-level data for measures of cataract surgery outcome, colonoscopy follow-up, heart...

Is a school-based physical activity intervention effective for increasing tibial bone strength in boys and girls?

Science.gov (United States)

Macdonald, Heather M; Kontulainen, Saija A; Khan, Karim M; McKay, Heather A

2007-03-01

This 16-month randomized, controlled school-based study compared change in tibial bone strength between 281 boys and girls participating in a daily program of physical activity (Action Schools! BC) and 129 same-sex controls. The simple, pragmatic intervention increased distal tibia bone strength in prepubertal boys; it had no effect in early pubertal boys or pre or early pubertal girls. Numerous school-based exercise interventions have proven effective for enhancing BMC, but none have used pQCT to evaluate the effects of increased loading on bone strength during growth. Thus, our aim was to determine whether a daily program of physical activity, Action Schools! BC (AS! BC) would improve tibial bone strength in boys and girls who were pre- (Tanner stage 1) or early pubertal (Tanner stage 2 or 3) at baseline. Ten schools were randomized to intervention (INT, 7 schools) or control (CON, 3 schools). The bone-loading component of AS! BC included a daily jumping program (Bounce at the Bell) plus 15 minutes/day of classroom physical activity in addition to regular physical education. We used pQCT to compare 16-month change in bone strength index (BSI, mg2/mm4) at the distal tibia (8% site) and polar strength strain index (SSIp, mm3) at the tibial midshaft (50% site) in 281 boys and girls participating in AS! BC and 129 same-sex controls. We used a linear mixed effects model to analyze our data. Children were 10.2+/-0.6 years at baseline. Intervention boys tended to have a greater increase in BSI (+774.6 mg2/mm4; 95% CI: 672.7, 876.4) than CON boys (+650.9 mg2/mm4; 95% CI: 496.4, 805.4), but the difference was only significant in prepubertal boys (p=0.03 for group x maturity interaction). Intervention boys also tended to have a greater increase in SSIp (+198.6 mm3; 95% CI: 182.9, 214.3) than CON boys (+177.1 mm3; 95% CI: 153.5, 200.7). Change in BSI and SSIp was similar between CON and INT girls. Our findings suggest that a simple, pragmatic program of daily activity

Timely and Effective Care - National

Data.gov (United States)

U.S. Department of Health & Human Services — Timely and Effective Care measures - national data. This data set includes national-level data for measures of heart attack care, heart failure care, pneumonia care,...

Timely and Effective Care - State

Data.gov (United States)

U.S. Department of Health & Human Services — Timely and Effective Care measures - state data. This data set includes state-level data for measures of heart attack care, heart failure care, pneumonia care,...

[Evaluation of nutrition mode and nutritional status and pro health education of children during the period of pubertal spurt in the city of Szczecin].

Science.gov (United States)

Goluch-Koniuszy, Zuzanna; Friedrich, Mariola; Radziszewska, Magdalena

2009-01-01

This research was aimed at evaluation of the method of nutrition and the state of nutrition in the children aged 13 during the period of pubertal spurt who had their body mass, body height and waist measurement defined. These values led to calculation of BMI, WC, and WHtR indicators, which were related to centile distribution of children from Warszawa and Lódź. Only in 63.6% of girls and 68.9% of boys from Szczecin schools the value of BMI was proper. The problem of accumulation of fat tissue (WC > or = 90 c) around the waist refers to nearly 14% of girls and 9.4% of boys. The value of the indicator WHtR > or = 90 c was found in 11% of the children under research. Children with overweight (BMI 90-97 c) and obesity (BMI > or = 97 c) were selected based on the value of BMI indicator. Their menus of three chosen at random weekdays were obtained. Analysis of the nutrition method of children with overweight and obesity showed low energy value of the diet, general protein, complex carbohydrates, cellulose, mineral components (Ca, Mg, Fe, Cu, Zn), A, E (girls), C (boys), group B vitamins and also liquids deficiency. The children have undergone a special pro health education in the form of "live" workshops and 3 months after an evaluation inquiry was conducted to assess the effects of the workshops. The analysis of the evaluation inquiry showed that the children have included in their diet breakfasts and afternoon snacks and to their main meal menus whole wheat products, larger quantity of vegetables, fruit and water. It has been also established that sweets, meals of fast food types, chips, pizzy and energizing drinks have been limited.

Long-term effects of an inpatient weight-loss program in obese children and the role of genetic predisposition-rationale and design of the LOGIC-trial.

Science.gov (United States)

Rank, Melanie; Siegrist, Monika; Wilks, Désirée C; Haller, Bernhard; Wolfarth, Bernd; Langhof, Helmut; Halle, Martin

2012-03-19

The prevalence of childhood obesity has increased worldwide, which is a serious concern as obesity is associated with many negative immediate and long-term health consequences. Therefore, the treatment of overweight and obesity in children and adolescents is strongly recommended. Inpatient weight-loss programs have shown to be effective particularly regarding short-term weight-loss, whilst little is known both on the long-term effects of this treatment and the determinants of successful weight-loss and subsequent weight maintenance.The purpose of this study is to evaluate the short, middle and long-term effects of an inpatient weight-loss program for children and adolescents and to investigate the likely determinants of weight changes, whereby the primary focus lies on the potential role of differences in polymorphisms of adiposity-relevant genes. The study involves overweight and obese children and adolescents aged 6 to 19 years, who participate in an inpatient weight-loss program for 4 to 6 weeks. It started in 2006 and it is planned to include 1,500 participants by 2013. The intervention focuses on diet, physical activity and behavior therapy. Measurements are taken at the start and the end of the intervention and comprise blood analyses (DNA, lipid and glucose metabolism, adipokines and inflammatory markers), anthropometry (body weight, height and waist circumference), blood pressure, pubertal stage, and exercise capacity. Physical activity, dietary habits, quality of life, and family background are assessed by questionnaires. Follow-up assessments are performed 6 months, 1, 2, 5 and 10 years after the intervention: Children will complete the same questionnaires at all time points and visit their general practitioner for examination of anthropometric parameters, blood pressure and assessment of pubertal stage. At the 5 and 10 year follow-ups, blood parameters and exercise capacity will be additionally measured. Apart from illustrating the short, middle and long

Effects of Plyometric and Sprint Training on Physical and Technical Skill Performance in Adolescent Soccer Players.

Science.gov (United States)

Sáez de Villarreal, Eduardo; Suarez-Arrones, Luis; Requena, Bernardo; Haff, Gregory G; Ferrete, Carlos

2015-07-01

To determine the influence of a short-term combined plyometric and sprint training (9 weeks) within regular soccer practice on explosive and technical actions of pubertal soccer players during the in-season. Twenty-six players were randomly assigned to 2 groups: control group (CG) (soccer training only) and combined group (CombG) (plyometric + acceleration + dribbling + shooting). All players trained soccer 4 times per week and the experimental groups supplemented the soccer training with a proposed plyometric-sprint training program for 40 minutes (2 days per weeks). Ten-meter sprint, 10-m agility with and without ball, CMJ and Abalakov vertical jump, ball-shooting speed, and Yo-Yo intermittent endurance test were measured before and after training. The experimental group followed a 9-week plyometric and sprint program (i.e., jumping, hurdling, bouncing, skipping, and footwork) implemented before the soccer training. Baseline-training results showed no significant differences between the groups in any of the variables tested. No improvement was found in the CG; however, meaningful improvement was found in all variables in the experimental group: CMJ (effect size [ES] = 0.9), Abalakov vertical jump (ES = 1.3), 10-m sprint (ES = 0.7-0.9), 10-m agility (ES = 0.8-1.2), and ball-shooting speed (ES = 0.7-0.8). A specific combined plyometric and sprint training within regular soccer practice improved explosive actions compared with conventional soccer training only. Therefore, the short-term combined program had a beneficial impact on explosive actions, such as sprinting, change of direction, jumping, and ball-shooting speed which are important determinants of match-winning actions in soccer performance. Therefore, we propose modifications to current training methodology for pubertal soccer players to include combined plyometric and speed training for athlete preparation in this sport.

Hypothesis: exposure to endocrine-disrupting chemicals may interfere with timing of puberty

DEFF Research Database (Denmark)

Mouritsen, A; Aksglaede, L; Sørensen, K

2010-01-01

and increasing prevalence of adiposity may contribute, but environmental factors are also likely to be involved. In particular, the widespread presence of endocrine-disrupting chemicals (EDCs) is suspected to contribute to the trend of earlier pubertal onset. The factors regulating the physiological onset...... of normal puberty are poorly understood. This hampers investigation of the possible role of environmental influences. There are many types of EDCs. One chemical may have more than one mode of action and the effects may depend on dose and duration of the exposure, as well as the developmental stage......A recent decline in onset of puberty - especially among girls - has been observed, first in the US in the mid-1990s and now also in Europe. The development of breast tissue in girls occurs at a much younger age and the incidence of precocious puberty (PP) is increasing. Genetic factors...

Time Limits : Effects on Recall

OpenAIRE

Hirano, Kinue

2000-01-01

This study investigates the effects of differing time limits and the level of language proficiency on the written recalls of 66 Japanese EFL undergraduates. Results showed that different time limits affected total recall, but not main ideas recalled. Regardless of proficiency level, the 20-minute group (Group 2) recalled a greater number of idea units than the 8-minute group (Group 1). However, no significant difference was found between Groups 1 and 2 regarding the recall of main ideas, alth...

Time perspective and positivity effects in Alzheimer's disease.

Science.gov (United States)

Bohn, Linzy; Kwong See, Sheree T; Fung, Helene H

2016-09-01

This study tested whether time perspective, a central tenant of socioemotional selectivity theory (Carstensen, 2006), moderates positivity effects in emotional memory. To provide measures of time perspective, young (YA; M = 22.48 years), young-old (YO; M = 67.56 years), old-old adults (OO; M = 80.24 years), and participants with moderate severity Alzheimer's disease (PAD; M = 84.28 years) completed a line task and reported subjective age. As expected, YA, YO, and OO reported successively more constrained future time perspectives. PAD showed distortion in time perspective, envisioning a future comparable with the YO, although closer matched in chronological age to OO adults. To evince positivity effects, participants were oriented to pairs of emotional images and were then tested for memory (recall and recognition) of the images. Recall and recognition memory for the images indicated an age-related advantage for positive over negative material (positivity effects). Time perspective, however, did not moderate these age effects. In memory performance, PAD were more comparable with OO adults with whom they shared a similar chronological age, rather than YO adults, who had a corresponding time perspective. These results suggest that age correlates that are shared by PAD and OO, such as reduced processing resources, rather than time perspective, may drive the age associated positivity effects. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Efeito da duração do tratamento com progestágeno e da maturidade sexual na taxa de prenhez em novilhas de corte: avaliação econômica e biológica Effect of the duration of progestagen exposure and sexual maturity on the pregnancy rate of beef heifers: economic and biological evaluation

Directory of Open Access Journals (Sweden)

Luiz Francisco Machado Pfeifer

2009-07-01

Full Text Available Os objetivos neste experimento foram avaliar o efeito do tempo de exposição a um progestágeno (P4 na taxa de prenhez de novilhas púberes e pré-púberes inseminadas em tempo-fixo (IATF e estudar o retorno econômico dos protocolos utilizados, por meio da comparação desses protocolos ao sistema tradicional de acasalamento natural aos 26 meses de idade. Foram utilizadas 114 novilhas da raça Bradford com 16 meses de idade, classificadas em quatro grupos de acordo com o tratamento e a maturidade sexual: GPPLP - pré-puberes, longo tratamento com P4 (n=21; e GPPCP - pré-puberes, curto tratamento com (n=19; GPLP - púberes, longo tratamento com P4 (n=34; e GPCP - púberes, curto tratamento com P4 (n=40. As novilhas do GPPLP e GPLP receberam no dia -8 um pessário intravaginal impregnado com acetato de medroxiprogesterona. No dia 0, o pessário foi removido e outro foi inserido, juntamente com uma injeção de 2,5 mg de benzoato de estradiol (BE. No dia 8, o pessário foi retirado e as novilhas receberam 0,5 mg de BE e 250 µg de cloprostenol sódico. A inseminação artificial em tempo fixo (IATF foi realizada 54 horas depois. As novilhas do GPPCP e GPCP receberam o mesmo tratamento de sincronização dos grupos GPPLP e GPLP, com exceção do AMP do dia -8 ao dia 0. A taxa de prenhez foi maior nas novilhas púberes (60,3% que nas pré-puberes (35,0%. No entanto, não foi detectado efeito do tempo de tratamento na taxa de prenhez nas novilhas púberes e pré-puberes. A resposta econômica na utilização de protocolos com P4 foi maior em novilhas aos 16 meses que no sistema de acasalamento aos 26 meses. A exposição prolongada a um P4 não foi eficiente para aumentar a taxa de prenhez de novilhas submetidas a IATF.The aim of this experiment was to evaluate the effect of the duration of progestagen (P4 exposure and sexual maturity of prepubertal and pubertal heifers submitted to timed artificial insemination (TAI. A hundred and fourteen 16

Dead time effects in laser Doppler anemometry measurements

DEFF Research Database (Denmark)

Velte, Clara Marika; Buchhave, Preben; George, William K.

2014-01-01

frequency range, starting around the cutoff frequency due to the finite size of the MV. Using computer-generated data mimicking the LDA data, these effects have previously been shown to appear due to the effect of dead time, i.e., the finite time during which the system is not able to acquire new...... measurements. These dead times can be traced back to the fact that the burst-mode LDA cannot measure more than one signal burst at a time. Since the dead time is approximately equal to the residence time for a particle traversing a measurement volume, we are dealing with widely varying dead times, which...

Life-history theory, chronic childhood illness and the timing of first reproduction in a British birth cohort.

Science.gov (United States)

Waynforth, David

2012-08-07

Life-history theoretical models show that a typical evolutionarily optimal response of a juvenile organism to high mortality risk is to reach reproductive maturity earlier. Experimental studies in a range of species suggest the existence of adaptive flexibility in reproductive scheduling to maximize fitness just as life-history theory predicts. In humans, supportive evidence has come from studies comparing neighbourhoods with different mortality rates, historical and cross-cultural data. Here, the prediction is tested in a novel way in a large (n = 9099), longitudinal sample using data comparing age at first reproduction in individuals with and without life-expectancy-reducing chronic disease diagnosed during childhood. Diseases selected for inclusion as chronic illnesses were those unlikely to be significantly affected by shifting allocation of effort away from reproduction towards survival; those which have comparatively large effects on mortality and life expectancy; and those which are not profoundly disabling. The results confirmed the prediction that chronic disease would associate with early age at first reproduction: individuals growing up with a serious chronic disease were 1.6 times more likely to have had a first child by age 30. Analysis of control variables also confirmed past research findings on links between being raised father-absent and early pubertal development and reproduction.

Descriptive review: hormonal influences on risk for eating disorder symptoms during puberty and adolescence.

Science.gov (United States)

Harden, K Paige; Kretsch, Natalie; Moore, Sarah R; Mendle, Jane

2014-11-01

Puberty is an important period of risk for the onset of eating pathology in adolescent females. This review focuses on changes in reproductive hormones during puberty as one specific psychopathogenic mechanism. Studies of puberty and eating disorder-related phenotypes were identified using search databases and the reference sections of previous literature. Correlational studies of adult women and experimental studies of animals provide evidence for the effects of reproductive hormones on eating disorder symptoms. Very few studies of puberty, however, have directly measured or tested the effects of hormonal change in samples of human adolescents. Commonly used measures of pubertal development, such as menarche or self-reported pubertal status, are relatively poor indicators of individual differences in hormones. The extent to which puberty-related hormonal change accounts for elevated risk for disordered eating remains unclear. Future research is necessary to elucidate the specific relations between hormonal change during puberty and risk for disordered eating. In particular, there is a need for longitudinal studies with multivariate measurement of pubertal development, including direct measures of change in reproductive hormones. © 2014 Wiley Periodicals, Inc.

PERIPUBERTAL PROCHLORAZ EXPOSURE STRONGLY INHIBITS TESTOSTERONE PRODUCTION, BUT HAS WEAK EFFECTS ON PUBERTY

Science.gov (United States)

Prochloraz (PCZ) is an imidazole fungicide that inhibits steroidogenesis and acts as an androgen receptor antagonist. We hypothesized that pubertal exposure to prochloraz would delay preputial separation and development of reproductive organs. Sprague Dawley rats were dosed wit...

Transcriptome data of peripheral white blood cells from beef heifers collected at the time of artificial insemination

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Sarah E. Dickinson

2018-06-01

Full Text Available The reproductive performance of heifers within their first breeding season influences the success of beef cattle operations. Therefore, a means to identify infertile and late breeding heifers before the start of the breeding season holds great promise for the future of the beef industry. Pubertal beef heifers were subjected to estrous synchronization and fixed time artificial insemination (FTAI. We collected peripheral blood from the heifers at the time of artificial insemination (AI and generated RNA sequencing data to characterize the transcriptome of peripheral white blood cells (PWBC. Following insemination, heifers were exposed to natural service for a defined breeding season, and pregnancy was evaluated to classify heifers into one of three groups: AI-pregnant, natural-bred (NB pregnant, and non-pregnant. The raw transcriptome data of PWBC is available on the NCBI GEO repository (GSE103628 where the reader can also find raw read counts and normalized gene expression data. The normalized data on transcript coverage can be visualized as a genome browser at HeiferFertilityRNAseq.org. Keywords: Biomarkers, Infertility, Pregnancy

The effects of phthalate and nonylphenol exposure on body size and secondary sexual characteristics during puberty.

Science.gov (United States)

Hou, Jia-Woei; Lin, Ching-Ling; Tsai, Yen-An; Chang, Chia-Huang; Liao, Kai-Wei; Yu, Ching-Jung; Yang, Winnie; Lee, Ming-Jun; Huang, Po-Chin; Sun, Chien-Wen; Wang, Yin-Han; Lin, Fang-Ru; Wu, Wen-Chiu; Lee, Meng-Chih; Pan, Wen-Harn; Chen, Bai-Hsiun; Wu, Ming-Tsang; Chen, Chu-Chih; Wang, Shu-Li; Lee, Ching-Chang; Hsiung, Chao Agnes; Chen, Mei-Lien

2015-10-01

Some phthalic acid esters (PAEs) and nonylphenol (NP) are endocrine-disrupting chemicals (EDCs) that are widely used in consumer products. Consequently, the general population is exposed simultaneously to both groups of chemicals. To investigate the single- and co-exposure effects of PAEs (DMP, DEP, DnBP, DiBP, BBzP, and DEHP) and NP on obesity and pubertal maturity to compare the body sizes of general adolescents with the complainants of the phthalate-tainted foods scandal that occurred in Taiwan. This study included 270 general adolescents aged 6.5-15.0 years and 38 complainants aged 6.5-8.5 years. Nine metabolites of the five PAEs and of NP were measured in urine. We used a questionnaire to evaluate pubertal maturity, measured anthropometric indices (APs) to assess body size, and collected urine samples to measure the two groups of chemicals. We found that urinary PAE metabolite concentrations (specifically, metabolites of DEP, DnBP, DiBP, and DEHP) were positively associated with the APs for abdominal obesity (including skinfold thickness, waist circumference, waist-to-height ratio, and waist-to-hip) and indicated a dose-response relationship. Mono-methyl phthalate (MMP) exposure was inversely associated with pubarche among boys. The daily intake of DEHP in general adolescents exceeded the reference doses (RfD-20 μg/kgbw/day) and tolerable daily intake (TDI-50 μg/kgbw/day) by 3.4% and 0.4%, respectively. No associations were observed between NP exposure or co-exposure and the APs or pubertal maturity. No significant differences were observed between general adolescents and the complainants with regard to weight, height, or BMI. The study suggests that PAE (specifically, DEP, DnBP, DiBP, and DEHP) exposure is associated with abdominal obesity in adolescents and that the APs for abdominal obesity are more sensitive than BMI for measuring obesity among adolescents. We suggest that the RfD and TDI for PAEs should be revised to provide sufficient protection

Body Image Satisfaction, Eating Attitudes and Perceptions of Female Body Silhouettes in Rural South African Adolescents.

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Titilola M Pedro

Full Text Available This study aims to examine the associations between BMI, disordered eating attitude, body dissatisfaction in female adolescents, and descriptive attributes assigned to silhouettes of varying sizes in male and female adolescents, aged 11 to 15, in rural South Africa. Height and weight were measured to determine BMI. Age and sex-specific cut-offs for underweight and overweight/obesity were determined using the International Obesity Task Force cut-offs. Body image satisfaction using Feel-Ideal Discrepancy (FID scores, Eating Attitudes Test-26 (EAT-26, and perceptual female silhouettes were collected through self-administered questionnaires in 385 adolescents from the Agincourt Health and Socio-Demographic Surveillance System (HSDSS. Participants self-reported their Tanner pubertal stage and were classified as early pubertal ( 2. Mid to post pubertal boys and girls were significantly heavier, taller, and had higher BMI values than their early pubertal counterparts (all p<0.001. The prevalence of overweight and obesity was higher in the girls than the boys in both pubertal stages. The majority (83.5% of the girls demonstrated body dissatisfaction (a desire to be thinner or fatter. The girls who wanted to be fatter had a significantly higher BMI than the girls who wanted to be thinner (p<0.001. There were no differences in EAT-26 scores between pubertal groups, within the same sex, and between boys and girls within the two pubertal groups. The majority of the boys and the girls in both pubertal groups perceived the underweight silhouettes to be "unhappy" and "weak" and the majority of girls in both pubertal groups perceived the normal silhouettes to be the "best". These findings suggest a need for policy intervention that will address a healthy body size among South African adolescents.

[Effect of anticancer treatment on leptin level, fat body mass (FM) and lean body mass (LBM)].

Science.gov (United States)

Krawczyk-Rybak, Maryna; Muszyńska-Rosłan, Katarzyna; Konstantynowicz, Jerzy; Solarz, Elzbieta; Wołczynski, Sławomir; Protas, Piotr

2004-01-01

Leptin plays an important role in the metabolism of adipose tissue. Considering that malignancy and its treatment cans affect normal development in childhood. We analysed the correlations between serum leptin levels and body composition after anticancer treatment. We studied 33 survivors (24 boys and 9 girls) who before our study, have been treated for acute lymphoblastic leukaemia (ALL) (n=23) and Hodgkin disease (n=10) after 7.15+/-3.5 years. Sixteen patients with ALL received cranial irradiation (12Gy). We measured body mass index (BM1) fat mass (FM) and lean body mass (LBM) using dual energy x-ray absorptiometry (DXA). We compared these results to the results obtained from reference values (SD score). Leptin levels were measured with the RIA method. 1. Mean leptin levels were higher in girls after puberty (10.93 ng/mL+/-8.9) than in boys (3.73 ng/mL+/-3. 7). In boys no differences were found in leptin levels between T2-4 and T5 stages. In girls the leptin values increased after puberty. Leptin SD score levels were higher in boys during (1.55 +/-1.0) and after puberty (1.46+/-0.75) and in girls - after puberty (1.19 +/-1.51). We did not find any influence of cranial irradiation (12Gy) or various methotrexate doses (5 g/m(2) vs. 19/m(2)) leptin values. 2. No difference in BMI SD score was found within the whole study group. 3. FM did not change ill boys during and after puberty, although FM SD score were higher during puberty (2.98 +/-4.8). In girls FM and FM SD score were higher after puberty. In boys and girls LBM augmented with pubertal development but LBM SD score in boys were lower after puberty (-1.67 +/-1.7) in comparison to puberty (0.2 +/-1.7). No differences were found between LBM SD score in girls during and after puberty. 4. We found a correlation between leptin levels and BMI (r=0.59 p=0.001) and FM (r=0.77 p=0.0001). 5. Relation of FM to LBM in boys remained unchanged, however in girls it increased within pubertal development. l. Anticancer

Effects of postnatal administration of diethylstilbestrol on puberty and thyroid function in male rats.

Science.gov (United States)

Shin, Jae-Ho; Kim, Tae Sung; Kang, Il Hyun; Kang, Tae Seok; Moon, Hyun Ju; Han, Soon-Young

2009-10-01

To examine the effects of diethylstilbestrol (DES) on male pubertal development and thyroid function, juvenile male Sprague-Dawley rats were given DES daily by oral intubation at doses of 10, 20 and 40 microg/kg/day from postnatal day 33 for 20 days. Prepuce separation was significantly delayed at the dose of 20 microg/kg/day and above in the DES-treated rats. DES treatment induced a significant reduction in the weights of testes, epididymides, the ventral prostate, seminal vesicles plus coagulating glands and fluid, levator ani bulbocavernosus muscles, Cowper's glands and the glans penis. The weights of the liver and adrenals increased in the DES-treated animals. DES caused a dose-dependent reduction in germ cells; in particular the spermatids were mainly affected. The serum levels of testosterone and luteinizing hormone were significantly reduced in the DES-treated groups, but that of estradiol decreased. No differences were observed in the serum thyroxine levels of the control and DES-treated groups. In microscopic observation of the DES-treated animals, degeneration of germ cells and tubular atrophy in the testis were noted, but there were no microscopic changes in the thyroid. These results indicate that DES affected the pubertal development of juvenile male rats and that its mode of action may be related to alterations in hormone levels.

The Effects of Immigration on NHS Waiting Times

OpenAIRE

Giuntella, Osea; Nicodemo, Catia; Vargas-Silva, Carlos

2015-01-01

This paper analyses the effects of immigration on waiting times in the National Health Service (NHS) in England. Linking administrative records from the Hospital Episode Statistics (2003-2012) with immigration data drawn from the UK Labour Force Survey, we find that immigration reduced waiting times for outpatient referrals and did not have significant effects on waiting times in Accident and Emergency (A&E) and elective care. These results are explained by the fact that immigration increases...

Time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging

International Nuclear Information System (INIS)

Wang Zhiwen; Wei Weixing; He Yanhe; Zhao Yuanqing; Pan Liyiji; Li Xuemei; Shi Shaodui; Li Guangxin

2010-01-01

The time effectiveness of capillary effect improvement of ramie fabrics processed by RF glow discharging was studied. The ramie fabrics were processed in fulfilling with different gas (O 2 , N 2 , Ar) by different parameters (such as pressure,power and time) plasma. The capillary effect of the ramie fabrics processed by RF glow discharging was tested at different time. The results indicate that the capillary effect of ramie fabrics processed by RF glow discharging has been improved, the improvement of the capillary effect firstly decrease rapidly, then slowly, and become stable after 15 day, it indicate that improvement of the ramie fabrics capillary has good time effectiveness, and the plasma parameter for the best capillary effect improvement of ramie fabric is 100 W and 40 Pa processed 20 min by oxygen plasma. (authors)

Eruption of the maxillary canines in relation to skeletal maturity.

Science.gov (United States)

Baccetti, Tiziano; Franchi, Lorenzo; De Lisa, Simona; Giuntini, Veronica

2008-05-01

Our aim in this study was to assess the relationship between the eruption of the permanent maxillary canines and skeletal maturity in subjects with different skeletal relationships in the sagittal and vertical planes. A sample of 152 subjects (63 boys, 89 girls) with erupting permanent maxillary canines was analyzed. On the lateral cephalograms, the stage of cervical vertebral maturation was assessed. Then the subjects were divided into prepeak (before the pubertal growth spurt, cervical stage [CS]1 and CS2), peak (during the pubertal growth spurt, CS3 and CS4), and postpeak (after the pubertal growth spurt, CS5 and CS6) groups. Skeletal relationships in the sagittal and vertical planes were evaluated, and relationships to timing of canine eruption were tested statistically. The prepeak group comprised 86 subjects, the peak group 66 subjects, and the postpeak group 0 subjects. The differences in prevalence rates between either the prepeak or peak groups and the postpeak group were statistically significant (P < 0.001). The prevalence rate for hyperdivergent subjects showing eruption of the permanent maxillary canine in the prepeak group (37.2%) was significantly higher than in the reference orthodontic population (21%). The eruption of the permanent maxillary canine can occur at any stage in skeletal maturation before the end the pubertal growth spurt (CS1-CS4), with hyperdivergent subjects more frequently having prepubertal canine eruption.

Pollinator effectiveness varies with experimental shifts in flowering time.

Science.gov (United States)

Rafferty, Nicole E; Ives, Anthony R

2012-04-01

The earlier flowering times exhibited by many plant species are a conspicuous sign of climate change. Altered phenologies have caused concern that species could suffer population declines if they flower at times when effective pollinators are unavailable. For two perennial wildflowers, Tradescantia ohiensis and Asclepias incarnata, we used an experimental approach to explore how changing phenology affects the taxonomic composition of the pollinator assemblage and the effectiveness of individual pollinator taxa. After finding in the previous year that fruit set varied with flowering time, we manipulated flowering onset in greenhouses, placed plants in the field over the span of five weeks, and measured pollinator effectiveness as the number of seeds produced after a single visit to a flower. The average effectiveness of pollinators and the expected rates of pollination success were lower for plants of both species flowering earlier than for plants flowering at historical times, suggesting there could be reproductive costs to earlier flowering. Whereas for A. incarnata, differences in average seed set among weeks were due primarily to changes in the composition of the pollinator assemblage, the differences for T. ohiensis were driven by the combined effects of compositional changes and increases over time in the effectiveness of some pollinator taxa. Both species face the possibility of temporal mismatch between the availability of the most effective pollinators and the onset of flowering, and changes in the effectiveness of individual pollinator taxa through time may add an unexpected element to the reproductive consequences of such mismatches.

Chromosome Y variants from different inbred mouse strains are linked to differences in the morphologic and molecular responses of cardiac cells to postpubertal testosterone

Directory of Open Access Journals (Sweden)

Churchill Gary A

2009-04-01

Full Text Available Abstract Background We have reported previously that when chromosome Y (chrY from the mouse strain C57BL/6J (ChrYC57 was substituted for that of A/J mice (ChrYA, cardiomyocytes from the resulting "chromosome substitution" C57BL/6J-chrYA strain were smaller than that of their C57BL/6J counterparts. In reverse, when chrYA from A/J mice was substituted for that of chrYC57, cardiomyocytes from the resulting A/J-chrYC57 strain were larger than in their A/J counterparts. We further used these strains to test whether: 1 the origin of chrY could also be linked to differences in the profile of gene expression in the hearts of adult male mice, and 2 post-pubertal testosterone could play a role in the differential morphologic and/or molecular effects of chrYC57 and chrYA. Results The increased size of cardiomyocytes from adult male C57BL/6J mice compared to C57BL/6J-chrYA resulted from the absence of hypertrophic effects of post-pubertal testosterone on cells from the latter strain. However, gene profiling revealed that the latter effect could not be explained on the basis of an insensitivity of cells from C57BL/6J-chrYA to androgens, since even more cardiac genes were affected by post-pubertal testosterone in C57BL/6J-chrYA hearts than in C57BL/6J. By testing for interaction between the effects of surgery and strain, we identified 249 "interaction genes" whose expression was affected by post-pubertal testosterone differentially according to the genetic origin of chrY. These interaction genes were found to be enriched within a limited number of signaling pathways, including: 1 p53 signaling, which comprises the interacting genes Ccnd1, Pten and Cdkn1a that are also potential co-regulators of the androgen receptors, and 2 circadian rhythm, which comprises Arntl/Bmal1, which may in turn regulate cell growth via the control of Cdkn1a. Conclusion Although post-pubertal testosterone increased the size of cardiomyocytes from male C56BL/6J mice but not that from

Association between Obesity and Puberty Timing: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Li, Wenyan; Liu, Qin; Deng, Xu; Chen, Yiwen; Liu, Shudan; Story, Mary

2017-10-24

This systematic review and meta-analysis examined the associations between obesity and puberty timing based on scientific evidence. Eight electronic databases were searched up to February 2017 for eligible studies, and two reviewers screened the articles and extracted the data independently. A total of 11 cohort studies with 4841 subjects met the inclusion criteria. Compared with the group of normal-weight girls, the obese group had more girls with menarche (RR: 1.87, 95% CI: 1.59-2.19, 2 studies). The number of girls with early puberty was significantly higher in the obese group than the normal weight group (RR: 2.44, 95% CI: 1.32-4.52, 5 studies). However, no differences were detected between girls who were obese or normal weight at age of menarche (WMD: -0.53 years, 95% CI: -1.24-0.19, 2 studies). There is no consistent result in the relationship between obesity and timing of pubertal onset in boys. Obesity may contribute to early onset of puberty in girls, while in boys, there is insufficient data. Given the limited number of cohort studies included in this meta-analysis, high-quality studies with strong markers of puberty onset, as well as standardized criteria for defining obesity are needed.

Association between Obesity and Puberty Timing: A Systematic Review and Meta-Analysis

Directory of Open Access Journals (Sweden)

Wenyan Li

2017-10-01

Full Text Available This systematic review and meta-analysis examined the associations between obesity and puberty timing based on scientific evidence. Eight electronic databases were searched up to February 2017 for eligible studies, and two reviewers screened the articles and extracted the data independently. A total of 11 cohort studies with 4841 subjects met the inclusion criteria. Compared with the group of normal-weight girls, the obese group had more girls with menarche (RR: 1.87, 95% CI: 1.59–2.19, 2 studies. The number of girls with early puberty was significantly higher in the obese group than the normal weight group (RR: 2.44, 95% CI: 1.32–4.52, 5 studies. However, no differences were detected between girls who were obese or normal weight at age of menarche (WMD: −0.53 years, 95% CI: −1.24–0.19, 2 studies. There is no consistent result in the relationship between obesity and timing of pubertal onset in boys. Obesity may contribute to early onset of puberty in girls, while in boys, there is insufficient data. Given the limited number of cohort studies included in this meta-analysis, high-quality studies with strong markers of puberty onset, as well as standardized criteria for defining obesity are needed.

Two Effective Ways to Implement Wait Time. A Symposium on Wait Time.

Science.gov (United States)

Swift, J. Nathan; And Others

The effects of instructional guides and a wait time feedback device (called a "Wait Timer") on the classroom interaction of middle school science teachers are examined. The Wait Timer, an unobtrusive indicator of wait time, is an automatic device that activates a light when a person speaks. The duration of the light at the end of a…

On the time-dependent Aharonov–Bohm effect

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Jian Jing

2017-11-01

Full Text Available The Aharonov–Bohm effect in the background of a time-dependent vector potential is re-examined for both non-relativistic and relativistic cases. Based on the solutions to the Schrodinger and Dirac equations which contain the time-dependent magnetic vector potential, we find that contrary to the conclusions in a recent paper (Singleton and Vagenas 2013 [4], the interference pattern will be altered with respect to time because of the time-dependent vector potential.

Single machine total completion time minimization scheduling with a time-dependent learning effect and deteriorating jobs

Science.gov (United States)

Wang, Ji-Bo; Wang, Ming-Zheng; Ji, Ping

2012-05-01

In this article, we consider a single machine scheduling problem with a time-dependent learning effect and deteriorating jobs. By the effects of time-dependent learning and deterioration, we mean that the job processing time is defined by a function of its starting time and total normal processing time of jobs in front of it in the sequence. The objective is to determine an optimal schedule so as to minimize the total completion time. This problem remains open for the case of -1 < a < 0, where a denotes the learning index; we show that an optimal schedule of the problem is V-shaped with respect to job normal processing times. Three heuristic algorithms utilising the V-shaped property are proposed, and computational experiments show that the last heuristic algorithm performs effectively and efficiently in obtaining near-optimal solutions.

Tunneling times and the Hartman effect revisited

International Nuclear Information System (INIS)

Olkhovsky, Vladislav S.; Recami, Erasmo; Raciti, Fabio

1995-05-01

In a recent review paper we proposed, within conventional quantum mechanics, new definitions for the sub-barrier tunnelling and reflection times. Aims of the present paper are: presenting and analysing the results of various numerical calculations (based on our equations) on the penetration and return times , , during tunneling inside a rectangular potential barrier, for various penetration depths x f ; putting forth and discussing suitable definitions, besides of the mean values, also of the variances (or dispersions) D τ T D τ R for the time durations of transmission and reflection process; mentioning that our definition τ T > for the average transmission time results to constitute an improvement of the ordinary dwell-time τ Dw formula; commenting upon some recent criticism by C.R. Leavens, on the basis of our new numerical results. We stress that our numerical evaluations confirm that our approach implied and implies, the existence of the Hartman effect: an effect that in these days (due to the theoretical connections between tunneling and evanescent wave propagation) is receiving - at Cologne, Berkeley, Florence and Vienna- indirect, but quite interesting, experimental verifications. At last, we briefly analyze some other definitions of tunnelling times. (author). 24 refs., 5 figs

Effect of time on dyeing wastewater treatment

Science.gov (United States)

Ye, Tingjin; Chen, Xin; Xu, Zizhen; Chen, Xiaogang; Shi, Liang; He, Lingfeng; Zhang, Yongli

2018-03-01

The preparation of carboxymethylchitosan wrapping fly-ash adsorbent using high temperature activated fly ash and sodium carboxymethyl chitosan (CWF), as with the iron-carbon micro-electrolysis process simulation and actual printing and dyeing wastewater. The effects of mixing time and static time on decolorization ratio, COD removing rate and turbidness removing rate were investigated. The experimental results show that the wastewater stirring times on the decolorization rate and COD removal rate and turbidity removal rate influence, with increasing of the stirring time, three showed a downward trend, and reached the peak at 10 min time; wastewater time on the decolorization ratio and COD removing efficiency and turbidness removing rate influence, along with standing time increase, three who declined and reached the maximum in 30min time.

Time-Delay Effects on Constitutive Gene Expression*

International Nuclear Information System (INIS)

Feng Yan-Ling; Wang Dan; Tang Xu-Lei; Dong Jian-Min

2017-01-01

The dynamics of constitutive gene expression with delayed mRNA degradation is investigated, where the intrinsic noise caused by the small number of reactant molecules is introduced. It is found that the oscillatory behavior claimed in previous investigations does not appear in the approximation of small time delay, and the steady state distribution still follows the Poisson law. Furthermore, we introduce the extrinsic noise induced by surrounding environment to explore the effects of this noise and time delay on the Fano factor. Based on a delay Langevin equation and the corresponding Fokker–Planck equation, the distribution of mRNA copy-number is achieved analytically. The time delay and extrinsic noise play similar roles in the gene expression system, that is, they are able to result in the deviation of the Fano factor from 1 evidently. The measured Fano factor for constitutive gene expression is slightly larger than 1, which is perhaps attributed to the time-delay effect. (paper)

Tunneling times and the Hartman effect revisited

Energy Technology Data Exchange (ETDEWEB)

Olkhovsky, Vladislav S. [Ukrainian Academy of Sciences, Kiev (Ukraine). Inst. for Nuclear Research]|[Istituto Nazionale di Fisica Nucleare, Catania (Italy); Recami, Erasmo [Universidade Estadual de Campinas, SP (Brazil). Dept. de Matematica Aplicada]|[Istituto Nazionale di Fisica Nucleare, Milano (Italy); Raciti, Fabio [Catania Univ. (Italy). Dipt. di Fisica; Zaichenko, Aleksandr K. [Ukrainian Academy of Sciences, Kiev (Ukraine)

1995-05-01

In a recent review paper we proposed, within conventional quantum mechanics, new definitions for the sub-barrier tunnelling and reflection times. Aims of the present paper are: presenting and analysing the results of various numerical calculations (based on our equations) on the penetration and return times < {tau}Pen >, <{tau}Ret >, during tunneling inside a rectangular potential barrier, for various penetration depths x{sub f}; putting forth and discussing suitable definitions, besides of the mean values, also of the variances (or dispersions) D {sup {tau}}T D {sup {tau}}R for the time durations of transmission and reflection process; mentioning that our definition < {sup {tau}}T > for the average transmission time results to constitute an improvement of the ordinary dwell-time {tau}{sup Dw} formula; commenting upon some recent criticism by C.R. Leavens, on the basis of our new numerical results. We stress that our numerical evaluations confirm that our approach implied and implies, the existence of the Hartman effect: an effect that in these days (due to the theoretical connections between tunneling and evanescent wave propagation) is receiving - at Cologne, Berkeley, Florence and Vienna- indirect, but quite interesting, experimental verifications. At last, we briefly analyze some other definitions of tunnelling times. (author). 24 refs., 5 figs.

Giant pubertal prolactinoma: Complete resolution following short ...

African Journals Online (AJOL)

2016-04-06

Apr 6, 2016 ... disappeared in a short time with cabergoline treatment. Key words: ... Hyperprolactinemia may cause impotence and hypogonadism in adult men, and rarely ... safe treatment method for male patients with giant prolactinoma.

Delayed puberty but normal fertility in mice with selective deletion of insulin receptors from Kiss1 cells.

Science.gov (United States)

Qiu, Xiaoliang; Dowling, Abigail R; Marino, Joseph S; Faulkner, Latrice D; Bryant, Benjamin; Brüning, Jens C; Elias, Carol F; Hill, Jennifer W

2013-03-01

Pubertal onset only occurs in a favorable, anabolic hormonal environment. The neuropeptide kisspeptin, encoded by the Kiss1 gene, modifies GnRH neuronal activity to initiate puberty and maintain fertility, but the factors that regulate Kiss1 neurons and permit pubertal maturation remain to be clarified. The anabolic factor insulin may signal nutritional status to these neurons. To determine whether insulin sensing plays an important role in Kiss1 neuron function, we generated mice lacking insulin receptors in Kiss1 neurons (IR(ΔKiss) mice). IR(ΔKiss) females showed a delay in vaginal opening and in first estrus, whereas IR(ΔKiss) males also exhibited late sexual maturation. Correspondingly, LH levels in IR(ΔKiss) mice were reduced in early puberty in both sexes. Adult reproductive capacity, body weight, fat composition, food intake, and glucose regulation were comparable between the 2 groups. These data suggest that impaired insulin sensing by Kiss1 neurons delays the initiation of puberty but does not affect adult fertility. These studies provide insight into the mechanisms regulating pubertal timing in anabolic states.

The role of puberty in the making and breaking of young ballet dancers: Perspectives of dance teachers.

Science.gov (United States)

Mitchell, Siobhan B; Haase, Anne M; Malina, Robert M; Cumming, Sean P

2016-02-01

Physical changes associated with puberty may conflict with functional and aesthetic ideals for a career in ballet. The dance teacher is in a position to guide young dancers through the pubertal transition, although dancers rather than teachers are often the focus of research. This study explores the social stimulus value of the female body in ballet as perceived by the dance teacher and how value may change during puberty. Ten UK dance teachers were interviewed; interpretative phenomenological analysis was used. Four main themes perceived by dance teachers emerged as central to the social stimulus value of the body among adolescent dancers: the ideal body; teacher approaches to managing puberty in the dance environment; puberty as a 'make or break' stage in ballet; and teacher awareness of pubertal onset and the implications of timing. Dance teachers can play an important role in moderating external and individual expectations during the pubertal transition. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Association between serum uric acid and metabolic syndrome components in prepubertal obese children (Tanner Stage I) from Nuevo León, Mexico - a preliminary study.

Science.gov (United States)

Perez, Elizabeth Solis; Medina, Mario Alberto González; Lomeli, Manuel Lopez-Cabanillas; González, Verónica Tijerina; Pérez, Jesús Zacarías Villarreal; Lavalle González, Fernando J; Imrhan, Victorine; Juma, Shanil; Vijayagopal, Parakat; Boonme, Kittipong; Prasad, Chandan

2017-01-01

Metabolic syndrome (MetS) is a major risk factor for cardiovascular disease and diabetes. Previous studies in obese children demonstrating a positive association between serum uric acid (sUA) and components of MetS are confounded by lack of uniformity in age and pubertal status of children. Therefore, we have examined the role of sUA in MetS and its components in pre-pubertal children (Tanner Stage I, age ≤ 9 years). Pre-pubertal obese children (32 boys, 27 girls, age 6-9 years) were recruited from Nuevo Leon, Mexico. For comparison, an equal number of children with normal body mass index (BMI) in the same age range (22 Boys, 39 girls, age 6-9 years) were also recruited from the same community. Presence of MetS and its components was defined according to the criteria of International Diabetes Federation. Fasting blood was analyzed for lipids, glucose, insulin, and uric acid. Among the obese children, sUA was positively associated with insulin resistance and hypertriglyceridemia and negatively associated with high density lipoprotein-cholesterol (HDLc). Subjects were three times more likely to have a MetS diagnosis per one unit (md/dL) difference in sUA. Of the 59 obese pre-pubertal children, 20 were classified as having MetS defined by the presence of abdominal obesity and two or more of other components described under methods. Of these, 57.1% (20/61) had sUA between 5.1 and 7.1 mg/dl. The findings of this study clearly indicate a positive relationship between uric acid and MetS and its components in pre-pubertal obese children with Tanner stage I and ≤9 years of age.

Prepubertal ultra-low-dose estrogen therapy is associated with healthier lipid profile than conventional estrogen replacement for pubertal induction in adolescent girls with Turner syndrome: preliminary results.

Science.gov (United States)

Ruszala, Anna; Wojcik, Malgorzata; Zygmunt-Gorska, Agata; Janus, Dominika; Wojtys, Joanna; Starzyk, Jerzy B

2017-08-01

The metabolic effects of prepubertal low-dose estrogen replacement (LE) therapy in Turner syndrome (TS) have not been fully investigated to date. The present study aimed to compare glucose and lipids metabolism in adolescents with TS on LE and conventional estrogen replacement (CE). In 14 TS (mean age 13.8), LE (17β-estradiol, 62.5 μg daily) was introduced before age 12 (mean age 10.5), and followed by a pubertal induction regimen after age 12, and in 14 CE was started after age 12 (mean 14, SD 1.96). Before, and 3 years after starting 17β-estradiol growth velocity, bone age, BMI, and selected parameters of glucose and lipids metabolism were assessed. There were no significant differences between LE and CE in the mean levels of any parameter before introduction of 17β-estradiol [total cholesterol (TC): 4.1 vs 4.3 mmol/L, LDL cholesterol (LDLc): 2.2 vs 2.4 mmol/L, HDL cholesterol (HDLc): 1.6 vs 1.4 mmol/L, triglycerides: 0.9 vs 1.0 mmol/L, fasting glucose: 4.2 vs 4.4 mmol/L, post-load glucose: 4.8 vs 5.5 mmol/L; fasting insulin: 6.8 vs 8.0 post-load insulin: 21.3 vs 67.0 μIU/mL, HOMA-IR 1.3 vs 1.6]. After three years of treatment, TC and LDLc levels were significantly lower in LE group (3.8 vs 4.4 mmol/L, p = 0.004; 1.9 vs 2.4 mmol/L, p = 0.03). The other parameters did not differ significantly. There was no negative impact on growth course and bone age advancement nor on BMI in LE group. Prepubertal LE is associated with healthier lipid profile than CE in girls with TS.

The effects of immigration on NHS waiting times.

Science.gov (United States)

Giuntella, Osea; Nicodemo, Catia; Vargas-Silva, Carlos

2018-03-01

This paper analyzes the effects of immigration on waiting times for the National Health Service (NHS) in England. Linking administrative records from Hospital Episode Statistics (2003-2012) with immigration data drawn from the UK Labour Force Survey, we find that immigration reduced waiting times for outpatient referrals and did not have significant effects on waiting times in accident and emergency departments (A&E) and elective care. The reduction in outpatient waiting times can be explained by the fact that immigration increases natives' internal mobility and that immigrants tend to be healthier than natives who move to different areas. Finally, we find evidence that immigration increased waiting times for outpatient referrals in more deprived areas outside of London. The increase in average waiting times in more deprived areas is concentrated in the years immediately following the 2004 EU enlargement and disappears in the medium term (e.g., 3-4 years). Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

The effects of oxcarbazepine and valproate therapies on growth in children with epilepsy.

Science.gov (United States)

Cansu, Ali; Yesilkaya, Ediz; Serdaroglu, Ayse; Camurdan, Orhun; Hirfanoglu, Tugba Luleci; Karaoglu, Abdulbaki; Bideci, Aysun; Cinaz, Peyami

2012-01-01

This study aimed to evaluate the effects of monotherapy with valproate or oxcarbazepine on the linear growth of children with idiopathic epilepsy. Antiepileptic treatment with valproate or oxcarbazepine was initiated in 76 patients. These were evaluated at baseline and at 6 and 18 months after commencement of therapy to determine height standard deviations (height z-scores). Serum ghrelin, insulin-like growth factor-1, and insulin-like growth factor-binding protein-3 levels were measured. In prepubertal patients receiving oxcarbazepine, height z-scores were elevated after 6 and 18 months of therapy (p = 0.008 and p = 0.001, respectively); in pubertal patients, a significant increase was noted at the 18th month of therapy (p = 0.004). In prepubertal patients receiving oxcarbazepine, serum standardized insulin-like growth factor-1 and insulin-like growth factor-binding protein-3 levels were significantly higher at the 18th month of therapy compared with baseline (p = 0.005 and p = 0.004, respectively). In puber-tal patients receiving valproate, serum ghrelin levels were significantly decreased at the 18th month of therapy compared with baseline (p = 0.006). Exposure to oxcarbazepine stimulated linear growth in epileptic patients through mechanisms involving the release of insulin-like growth factor-1 and insulin-like growth factor-binding protein-3. In contrast, expo-sure to valproate did not affect linear growth, but did lead to a decrease in serum ghrelin levels.

Effectiveness of Multivariate Time Series Classification Using Shapelets

Directory of Open Access Journals (Sweden)

A. P. Karpenko

2015-01-01

Full Text Available Typically, time series classifiers require signal pre-processing (filtering signals from noise and artifact removal, etc., enhancement of signal features (amplitude, frequency, spectrum, etc., classification of signal features in space using the classical techniques and classification algorithms of multivariate data. We consider a method of classifying time series, which does not require enhancement of the signal features. The method uses the shapelets of time series (time series shapelets i.e. small fragments of this series, which reflect properties of one of its classes most of all.Despite the significant number of publications on the theory and shapelet applications for classification of time series, the task to evaluate the effectiveness of this technique remains relevant. An objective of this publication is to study the effectiveness of a number of modifications of the original shapelet method as applied to the multivariate series classification that is a littlestudied problem. The paper presents the problem statement of multivariate time series classification using the shapelets and describes the shapelet–based basic method of binary classification, as well as various generalizations and proposed modification of the method. It also offers the software that implements a modified method and results of computational experiments confirming the effectiveness of the algorithmic and software solutions.The paper shows that the modified method and the software to use it allow us to reach the classification accuracy of about 85%, at best. The shapelet search time increases in proportion to input data dimension.

Puberty and Adolescence as a Time of Vulnerability to Stressors that Alter Neurobehavioral Processes

Science.gov (United States)

Holder, Mary K.; Blaustein, Jeffrey D.

2013-01-01

Puberty and adolescence are major life transitions during which an individual’s physiology and behavior changes from that of a juvenile to that of an adult. Here we review studies documenting the effects of stressors during pubertal and adolescent development on the adult brain and behavior. The experience of complex or compound stressors during puberty/adolescence generally increases stress reactivity, increases anxiety and depression, and decreases cognitive performance in adulthood. These behavioral changes correlate with decreased hippocampal volumes and alterations in neural plasticity. Moreover, stressful experiences during puberty disrupt behavioral responses to gonadal hormones both in sexual performance and on cognition and emotionality. These behavioral changes correlate with altered estrogen receptor densities in some estrogen-concentrating brain areas, suggesting a remodeling of the brain’s response to hormones. A hypothesis is presented that activation of the immune system results in chronic neuroinflammation that may mediate the alterations of hormone-modulated behaviors in adulthood. PMID:24184692

Stress during adolescence increases novelty seeking and risk taking behavior in male and female rats

Directory of Open Access Journals (Sweden)

Maria eToledo

2011-04-01

Full Text Available Adolescence is a period of major physical, hormonal and psychological change. It is also characterized by a significant increase in the incidence of psychopathologies and this increase is gender-specific. Likewise, stress during adolescence is associated with the development of psychiatric disorders later in life. Previously, using a rat model of psychogenic stress (exposure to predator odor followed by placement on an elevated platform during the pre-pubertal period (postnatal days 28-30, we reported sex-specific effects on auditory and contextual fear conditioning. Here, we study the short-term impact of psychogenic stress before and during puberty (postnatal days 28-42 on behavior (novelty seeking, risk taking, anxiety and depression and hypothalamus-pituitary-adrenocortical (HPA axis activation during late adolescence (postnatal days 45-51. Peri-pubertal stress decreased anxiety-like behavior and increased risk taking and novelty seeking behaviors during late adolescence (measured with the elevated plus maze, open field and exposure to novel object tests and intake of chocopop pellets before or immediate after stress. Finally neither depressive-like behavior (measured at the forced swim test nor HPA response to stress (blood corticosterone and glucose were affected by peri-pubertal stress. Nevertheless, when controlling for the basal anxiety of the mothers, animals exposed to peri-pubertal stress showed a significant decrease in corticosterone levels immediate after an acute stressor. The results from this study suggest that exposure to mild stressors during the peri-pubertal period induces a broad spectrum of behavioral changes in late adolescence, which may exacerbate the independence-building behaviors naturally happening during this transitional period (increase in curiosity, sensation-seeking and risk taking behaviors.

Timing of puberty and physical growth in obese children: a longitudinal study in boys and girls.

Science.gov (United States)

De Leonibus, C; Marcovecchio, M L; Chiavaroli, V; de Giorgis, T; Chiarelli, F; Mohn, A

2014-08-01

To assess whether puberty and physical growth vary in obese when compared to normal-weight children. One hundred obese pre-pubertal children (44 boys; mean age (±SD): 9.01 ± 0.62 years; 56 girls; 8.70 ± 0.57 years) were compared to 55 normal-weight controls (27 boys; 9.17 ± 0.26 years; 28 girls; 8.71 ± 0.62 years). All study participants were followed prospectively with 6-monthly follow-up visits. At each study visit, height, weight, body mass index (BMI) and pubertal stage were assessed. Obese children entered puberty and achieved later stages of puberty earlier than controls (onset of puberty: boys: 11.66 ± 1.00 vs. 12.12 ± 0.91 years, P = 0.049; girls: 9.90 ± 0.78 vs. 10.32 ± 1.70, P = 0.016; late puberty: boys: 13.33 ± 0.71 vs. 14.47 ± 1.00 years, P puberty (β = -0.506, P puberty (β = -0.514, P puberty and completion of puberty and an impaired height gain during puberty. © 2013 The Authors. Pediatric Obesity © 2013 International Association for the Study of Obesity.

Long-term effects of an inpatient weight-loss program in obese children and the role of genetic predisposition-rationale and design of the LOGIC-trial

Directory of Open Access Journals (Sweden)

Rank Melanie

2012-03-01

Full Text Available Abstract Background The prevalence of childhood obesity has increased worldwide, which is a serious concern as obesity is associated with many negative immediate and long-term health consequences. Therefore, the treatment of overweight and obesity in children and adolescents is strongly recommended. Inpatient weight-loss programs have shown to be effective particularly regarding short-term weight-loss, whilst little is known both on the long-term effects of this treatment and the determinants of successful weight-loss and subsequent weight maintenance. The purpose of this study is to evaluate the short, middle and long-term effects of an inpatient weight-loss program for children and adolescents and to investigate the likely determinants of weight changes, whereby the primary focus lies on the potential role of differences in polymorphisms of adiposity-relevant genes. Methods/Design The study involves overweight and obese children and adolescents aged 6 to 19 years, who participate in an inpatient weight-loss program for 4 to 6 weeks. It started in 2006 and it is planned to include 1,500 participants by 2013. The intervention focuses on diet, physical activity and behavior therapy. Measurements are taken at the start and the end of the intervention and comprise blood analyses (DNA, lipid and glucose metabolism, adipokines and inflammatory markers, anthropometry (body weight, height and waist circumference, blood pressure, pubertal stage, and exercise capacity. Physical activity, dietary habits, quality of life, and family background are assessed by questionnaires. Follow-up assessments are performed 6 months, 1, 2, 5 and 10 years after the intervention: Children will complete the same questionnaires at all time points and visit their general practitioner for examination of anthropometric parameters, blood pressure and assessment of pubertal stage. At the 5 and 10 year follow-ups, blood parameters and exercise capacity will be additionally

Delay time and Hartman effect in strain engineered graphene

International Nuclear Information System (INIS)

Chen, Xi; Deng, Zhi-Yong; Ban, Yue

2014-01-01

Tunneling times, including group delay and dwell time, are studied for massless Dirac electrons transmitting through a one-dimensional barrier in strain-engineered graphene. The Hartman effect, the independence of group delay on barrier length, is induced by the strain effect, and associated with the transmission gap and the evanescent mode. The influence of barrier height/length and strain modulus/direction on the group delay is also discussed, which provides the flexibility to control the group delay with applications in graphene-based devices. The relationship between group delay and dwell time is finally derived to clarify the nature of the Hartman effect

Time-dependent effects of cardiovascular exercise on memory

DEFF Research Database (Denmark)

Roig, Marc; Thomas, Richard; Mang, Cameron S

2016-01-01

We present new evidence supporting the hypothesis that the effects of cardiovascular exercise on memory can be regulated in a time-dependent manner. When the exercise stimulus is temporally coupled with specific phases of the memory formation process, a single bout of cardiovascular exercise may...... be sufficient to improve memory. SUMMARY: The timing of exercise in relation to the information to be remembered is critical to maximize the effects of acute cardiovascular exercise on memory....

Developmental Programming: Prenatal and Postnatal Androgen Antagonist and Insulin Sensitizer Interventions Prevent Advancement of Puberty and Improve LH Surge Dynamics in Prenatal Testosterone-Treated Sheep.

Science.gov (United States)

Padmanabhan, Vasantha; Veiga-Lopez, Almudena; Herkimer, Carol; Abi Salloum, Bachir; Moeller, Jacob; Beckett, Evan; Sreedharan, Rohit

2015-07-01

Prenatal T excess induces maternal hyperinsulinemia, early puberty, and reproductive/metabolic defects in the female similar to those seen in women with polycystic ovary syndrome. This study addressed the organizational/activational role of androgens and insulin in programming pubertal advancement and periovulatory LH surge defects. Treatment groups included the following: 1) control; 2) prenatal T; 3) prenatal T plus prenatal androgen antagonist, flutamide; 4) prenatal T plus prenatal insulin sensitizer, rosiglitazone; 5) prenatal T and postnatal flutamide; 6) prenatal T and postnatal rosiglitazone; and 7) prenatal T and postnatal metformin. Prenatal treatments spanned 30-90 days of gestation and postnatal treatments began at approximately 8 weeks of age and continued throughout. Blood samples were taken twice weekly, beginning at approximately 12 weeks of age to time puberty. Two-hour samples after the synchronization with prostaglandin F2α were taken for 120 hours to characterize LH surge dynamics at 7 and 19 months of age. Prenatal T females entered puberty earlier than controls, and all interventions prevented this advancement. Prenatal T reduced the percentage of animals having LH surge, and females that presented LH surge exhibited delayed timing and dampened amplitude of the LH surge. Prenatal androgen antagonist, but not other interventions, restored LH surges without normalizing the timing of the surge. Normalization of pubertal timing with prenatal/postnatal androgen antagonist and insulin sensitizer interventions suggests that pubertal advancement is programmed by androgenic actions of T involving insulin as a mediary. Restoration of LH surges by cotreatment with androgen antagonist supports androgenic programming at the organizational level.

Effects of Social Constraints on Career Maturity: The Mediating Effect of the Time Perspective

Science.gov (United States)

Kim, Kyung-Nyun; Oh, Se-Hee

2013-01-01

Previous studies have provided mixed results for the effects of social constraints on career maturity. However, there has been growing interest in these effects from the time perspective. Few studies have examined the effects of social constraints on the time perspective which in turn influences career maturity. This study examines the mediating…

The role of testosterone and estradiol in brain volume changes across adolescence: a longitudinal structural MRI study.

Science.gov (United States)

Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Kan, Eric; Dahl, Ronald E; Sowell, Elizabeth R

2014-11-01

It has been postulated that pubertal hormones may drive some neuroanatomical changes during adolescence, and may do so differently in girls and boys. Here, we use growth curve modeling to directly assess how sex hormones [testosterone (T) and estradiol (E₂)] relate to changes in subcortical brain volumes utilizing a longitudinal design. 126 adolescents (63 girls), ages 10 to 14, were imaged and restudied ∼2 years later. We show, for the first time, that best-fit growth models are distinctly different when using hormones as compared to a physical proxy of pubertal maturation (Tanner Stage) or age, to predict brain development. Like Tanner Stage, T and E₂ predicted white matter and right amygdala growth across adolescence in both sexes, independent of age. Tanner Stage also explained decreases in both gray matter and caudate volumes, whereas E₂ explained only gray matter decreases and T explained only caudate volume decreases. No pubertal measures were related to hippocampus development. Although specificity was seen, sex hormones had strikingly similar relationships with white matter, gray matter, right amygdala, and bilateral caudate volumes, with larger changes in brain volume seen at early pubertal maturation (as indexed by lower hormone levels), followed by less robust, or even reversals in growth, by late puberty. These novel longitudinal findings on the relationship between hormones and brain volume change represent crucial first steps toward understanding which aspects of puberty influence neurodevelopment. Copyright © 2014 Wiley Periodicals, Inc.

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African Journals Online (AJOL)

agnelles de la naissance au Sevrage et a la monte, Page de la mere ont un effet significatif sur le poids vif a la puberté. L'âge à la puberté estaussi influence (p < 0.05) par le taux de croissance de la naissance a la monte. 77 a 84% des agnelles Romney nées pendant le printemps (avril) ont atteint la puberté en automne ...

Time management: an imperative factor to effective service delivery ...

African Journals Online (AJOL)

In Nigeria, the need for time management in organizations especially the public ... of time management that can lead to employee effectiveness and efficiency in the ... time audit in their work place, be prepared to adjust to the best use of time.

Review of time-dose effects in radiation therapy

International Nuclear Information System (INIS)

Peschel, R.E.; Fischer, J.J.

1980-01-01

A historical review of conventional fractionation offers little confidence that such treatment is optimal for all tumors. Thus manipulation of time-dose schedules may provide a relatively inexpensive yet potentially useful technique for improving therapeutic results in radiation therapy. Consideration of basic radiobiological principles and animal model data illustrates the complex and heterogeneous nature of normal tissue and tumor response to time-dose effects and supports the hypothesis that better time-dose prescriptions can be found in clinical practice. The number of possible time-dose prescriptions is very large, and a review of the clinical trials using nonconventional fractionation demonstrates that the sampled portion of the total three-dimensional space of time, fraction number, and dose has been very small. Only carefully designed clinical trials can establish the therapeutic advantage of a new treatment schedule, and methods for selecting the most promising schedules are discussed. The use of simple data reduction formulas for time-dose effects should be discarded since they ignore the very complexity and heterogeneity of tissues and tumors which may form the basis of improved clinical results

Predictors of growth and decline in leisure time physical activity from adolescence to adulthood.

Science.gov (United States)

Wichstrøm, Lars; von Soest, Tilmann; Kvalem, Ingela Lundin

2013-07-01

To study the predictors of change in leisure time physical activity (LTPA) from adolescence to young adulthood. A nationally representative sample of 3,251 Norwegian students between 12 and 19 years of age were initially surveyed, and follow-up surveys were conducted three times over a 13-year period. The initial response rate was 97%, and retention rates for the three follow-up sessions were 92%, 84%, and 82%, respectively. Four groups of predictors were assessed: sociodemographics, such as gender, age, parental socioeconomic status, pubertal status, and grades; previous LTPA, such as the amount of LTPA and sports club membership; athletic self-concept and depressive symptoms; and other health behaviors, such as smoking, dieting, and body mass. Autoregressive cross-lagged analyses were supplemented with latent growth-curve analyses. Membership in a sports club and a positive athletic self-concept in adolescence predicted a high level of LTPA in adulthood, whereas smoking tobacco, high BMI, and depressive symptoms in adolescence predicted low levels of LTPA. Engaging adolescents in organized sports and enhancing adolescents' athletic self-concept may increase the number of adults who are physically active. Preventive efforts to reduce tobacco consumption, obesity, and depression in adolescence may also contribute to an increase in adult LTPA. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Dissipative Effect and Tunneling Time

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Samyadeb Bhattacharya

2011-01-01

Full Text Available The quantum Langevin equation has been studied for dissipative system using the approach of Ford et al. Here, we have considered the inverted harmonic oscillator potential and calculated the effect of dissipation on tunneling time, group delay, and the self-interference term. A critical value of the friction coefficient has been determined for which the self-interference term vanishes. This approach sheds new light on understanding the ion transport at nanoscale.

Time to Work or Time to Play: The Effect of Student Employment on Homework, Housework, Screen Time, and Sleep

OpenAIRE

Sabrina Wulff Pabilonia; Charlene Marie Kalenkoski

2009-01-01

Recent research suggests that working while in high school reduces the amount of time students spend doing homework. However, an additional hour of work leads to a reduction in homework by much less than one hour, suggesting a reduction in other activities. This paper uses data from the 2003-2007 American Time Use Surveys (ATUS) to investigate the effects of market work on the time students spend on homework, sleeping, household work, and screen time. Results show that an increase in paid wor...

Sequencing Effects of Plyometric Training Applied Before or After Regular Soccer Training on Measures of Physical Fitness in Young Players.

Science.gov (United States)

Ramirez-Campillo, Rodrigo; Alvarez, Cristian; Gentil, Paulo; Loturco, Irineu; Sanchez-Sanchez, Javier; Izquierdo, Mikel; Moran, Jason; Nakamura, Fabio Y; Chaabene, Helmi; Granacher, Urs

2018-03-22

To compare the effects of short-term (i.e., 7 week) plyometric training applied before (PJT-B) or after (PJT-A) soccer practice on components of physical fitness in young soccer players, a single-blind randomized controlled trial was conducted. Post-pubertal boys aged 17.0±0.5 years were allocated to three groups: PJT-B (n=12), PJT-A (n=14), and control (CON; n=12). The outcome measures included tests to evaluate 20-m speed, standing long jump [SLJ], squat jump [SJ], countermovement jump [CMJ], and drop jump [DJ], 20-m multistage shuttle running speed [MSSRT], and Illinois change of direction speed [ICODT]. While the CON performed soccer-specific training, the PJT-A and PJT-B groups conducted the same soccer-specific sessions but replaced ∼11% of their time with plyometric training. The PJT-B group performed plyometric exercises after a warm-up program, and the PJT-A group conducted plyometric exercises ∼10 minutes after the completion of soccer training. Analyses of variance (ANOVAs) were used to detect differences between groups in all variables for pre- and post-training tests. Main effects of time (all pplyometric training is effective in improving measures of physical fitness in young male soccer players when combined with regular soccer training. More specifically, larger training induced effects on physical fitness were registered if plyometric training was conducted prior to soccer specific training.

Time- & Load-Dependence of Triboelectric Effect.

Science.gov (United States)

Pan, Shuaihang; Yin, Nian; Zhang, Zhinan

2018-02-06

Time- and load-dependent friction behavior is considered as important for a long time, due to its time-evolution and force-driving characteristics. However, its electronic behavior, mainly considered in triboelectric effect, has almost never been given the full attention and analyses from the above point of view. In this paper, by experimenting with fcc-latticed aluminum and copper friction pairs, the mechanical and electronic behaviors of friction contacts are correlated by time and load analyses, and the behind physical understanding is provided. Most importantly, the difference of "response lag" in force and electricity is discussed, the extreme points of coefficient of friction with the increasing normal loads are observed and explained with the surface properties and dynamical behaviors (i.e. wear), and the micro and macro theories linking tribo-electricity to normal load and wear (i.e. the physical explanation between coupled electrical and mechanical phenomena) are successfully developed and tested.

High-Throughput Sequencing Reveals Hypothalamic MicroRNAs as Novel Partners Involved in Timing the Rapid Development of Chicken (Gallus gallus) Gonads.

Science.gov (United States)

Han, Wei; Zou, Jianmin; Wang, Kehua; Su, Yijun; Zhu, Yunfen; Song, Chi; Li, Guohui; Qu, Liang; Zhang, Huiyong; Liu, Honglin

2015-01-01

Onset of the rapid gonad growth is a milestone in sexual development that comprises many genes and regulatory factors. The observations in model organisms and mammals including humans have shown a potential link between miRNAs and development timing. To determine whether miRNAs play roles in this process in the chicken (Gallus gallus), the Solexa deep sequencing was performed to analyze the profiles of miRNA expression in the hypothalamus of hens from two different pubertal stages, before onset of the rapid gonad development (BO) and after onset of the rapid gonad development (AO). 374 conserved and 46 novel miRNAs were identified as hypothalamus-expressed miRNAs in the chicken. 144 conserved miRNAs were showed to be differentially expressed (reads > 10, P time quantitative RT-PCR (qRT-PCR) method. 2013 putative genes were predicted as the targets of the 15 most differentially expressed miRNAs (fold-change > 4.0, P times by the miRNAs. qRT-PCR revealed the basic transcription levels of these clock genes were much higher (P development of chicken gonads. Considering the characteristics of miRNA functional conservation, the results will contribute to the research on puberty onset in humans.

Materialism Moderates the Effect of Accounting for Time on Prosocial Behaviors.

Science.gov (United States)

Li, Jibo; Chen, Yingying; Huang, Xiting

2015-01-01

Accounting for time is defined as putting a price on time. Researchers have demonstrated that accounting for time reduces the time individuals spend on others; however, its association with monetary donations has not been examined. We hypothesized that accounting for time will activate a utility mindset that would affect one's allocation of time and money. In Study 1, the mediating effect of utility mindsets on the relationship between accounting for time and prosocial behavior was examined. In Study 2, we examined the effect of accounting for time on time spent helping and donating money, and the moderating role of material values on the relationship between accounting for time and prosocial behavior. Results showed that accounting for time activated a mindset of utility maximization that, in turn, reduced participants' prosocial behavior; moreover, materialism moderated the effect of accounting for time on prosocial behavior.

Is the kisspeptin system involved in responses to food restriction in order to preserve reproduction in pubertal male sea bass (Dicentrarchus labrax)?

Science.gov (United States)

Escobar, Sebastián; Felip, Alicia; Zanuy, Silvia; Carrillo, Manuel

2016-09-01

Previous works on European sea bass have determined that long-term exposure to restrictive feeding diets alters the rhythms of some reproductive/metabolic hormones, delaying maturation and increasing apoptosis during gametogenesis. However, exactly how these diets affect key genes and hormones on the brain-pituitary-gonad (BPG) axis to trigger puberty is still largely unknown. We may hypothesize that all these signals could be integrated, at least in part, by the kisspeptin system. In order to capture a glimpse of these regulatory mechanisms, kiss1 and kiss2 mRNA expression levels and those of their kiss receptors (kiss1r, kiss2r) were analyzed in different areas of the brain and in the pituitary of pubertal male sea bass during gametogenesis. Furthermore, other reproductive hormones and factors as well as the percentage of males showing full spermiation were also analyzed. Treated fish fed maintenance diets provided evidence of overexpression of the kisspeptin system in the main hypophysiotropic regions of the brain throughout the entire sexual cycle. Conversely, Gnrh1 and gonadotropin pituitary content and plasma sexual steroid levels were downregulated, except for Fsh levels, which were shown to increase during spermiation. Treated fish exhibited lower rates of spermiation as compared to control group and a delay in its accomplishment. These results demonstrate how the kisspeptin system and plasma Fsh levels are differentially affected by maintenance diets, causing a retardation, but not a full blockage of the reproductive process in the teleost fish European sea bass. This suggests that a hormonal adaptive strategy may be operating in order to preserve reproductive function in this species. Copyright © 2016 Elsevier Inc. All rights reserved.

Time-of-day effects in implicit racial in-group preferences are likely selection effects, not circadian rhythms

Directory of Open Access Journals (Sweden)

Timothy P. Schofield

2016-04-01

Full Text Available Time-of-day effects in human psychological functioning have been known of since the 1800s. However, outside of research specifically focused on the quantification of circadian rhythms, their study has largely been neglected. Moves toward online data collection now mean that psychological investigations take place around the clock, which affords researchers the ability to easily study time-of-day effects. Recent analyses have shown, for instance, that implicit attitudes have time-of-day effects. The plausibility that these effects indicate circadian rhythms rather than selection effects is considered in the current study. There was little evidence that the time-of-day effects in implicit attitudes shifted appropriately with factors known to influence the time of circadian rhythms. Moreover, even variables that cannot logically show circadian rhythms demonstrated stronger time-of-day effects than did implicit attitudes. Taken together, these results suggest that time-of-day effects in implicit attitudes are more likely to represent processes of selection rather than circadian rhythms, but do not rule out the latter possibility.

Time-of-day effects in implicit racial in-group preferences are likely selection effects, not circadian rhythms.

Science.gov (United States)

Schofield, Timothy P

2016-01-01

Time-of-day effects in human psychological functioning have been known of since the 1800s. However, outside of research specifically focused on the quantification of circadian rhythms, their study has largely been neglected. Moves toward online data collection now mean that psychological investigations take place around the clock, which affords researchers the ability to easily study time-of-day effects. Recent analyses have shown, for instance, that implicit attitudes have time-of-day effects. The plausibility that these effects indicate circadian rhythms rather than selection effects is considered in the current study. There was little evidence that the time-of-day effects in implicit attitudes shifted appropriately with factors known to influence the time of circadian rhythms. Moreover, even variables that cannot logically show circadian rhythms demonstrated stronger time-of-day effects than did implicit attitudes. Taken together, these results suggest that time-of-day effects in implicit attitudes are more likely to represent processes of selection rather than circadian rhythms, but do not rule out the latter possibility.

An effective approach to the problem of time

NARCIS (Netherlands)

Bojowald, M.; Höhn, P.A.|info:eu-repo/dai/nl/330827952; Tsobanjan, A.

2010-01-01

A practical way to deal with the problem of time in quantum cosmology and quantum gravity is proposed. The main tool is effective equations, which mainly restrict explicit considerations to semiclassical regimes but have the crucial advantage of allowing the consistent use of local internal times in

Effects of daylight savings time changes on stock market volatility.

Science.gov (United States)

Berument, M Hakan; Dogan, Nukhet; Onar, Bahar

2010-04-01

The presence of daylight savings time effects on stock returns and on stock volatility was investigated using an EGARCH specification to model the conditional variance. The evidence gathered from the major United States stock markets for the period between 1967 and 2007 did not support the existence of the daylight savings time effect on stock returns or on volatility. Returns on the first business day following daylight savings time changes were not lower nor was the volatility higher, as would be expected if there were an effect.

The timing of normal puberty and the age limits of sexual precocity: variations around the world, secular trends, and changes after migration.

Science.gov (United States)