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Sample records for advanced pubertal maturation

  1. Epigenetic mechanisms in pubertal brain maturation

    PubMed Central

    Morrison, Kathleen E.; Rodgers, Ali B.; Morgan, Christopher P.; Bale, Tracy L.

    2014-01-01

    Puberty is a critical period of development during which the reemergence of gonadotropin releasing hormone secretion from the hypothalamus triggers a cascade of hormone-dependent processes. Maturation of specific brain regions including the prefrontal cortex occurs during this window, but the complex mechanisms underlying these dynamic changes are not well understood. Particularly, the potential involvement of epigenetics in this programming has been under-examined. The epigenome is known to guide earlier stages of development, and it is similarly poised to regulate vital pubertal-driven brain maturation. Further, as epigenetic machinery is highly environmentally responsive, its involvement may also lend this period of growth to greater vulnerability to external insults, resulting in reprogramming and increased disease risk. Importantly, neuropsychiatric diseases commonly present in individuals during or immediately following puberty, and environmental perturbations including stress may precipitate disease onset by disrupting the normal trajectory of pubertal brain development via epigenetic mechanisms. In this review, we discuss epigenetic processes involved in pubertal brain maturation, the potential points of derailment, and the importance of future studies for understanding this dynamic developmental window and gaining a better understanding of neuropsychiatric disease risk. PMID:24239720

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

    PubMed

    de Water, Erik; Braams, Barbara R; Crone, Eveline A; Peper, Jiska S

    2013-02-01

    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 between pubertal maturation and alcohol use. The goal of the present study was twofold. In Experiment 1, we investigated whether advanced pubertal maturation is associated with higher levels of alcohol use, when controlling for age. To this end, questionnaires on pubertal development and alcohol use were administered to a large sample of 797 Dutch adolescents (405 boys) aged 11-16 years. In Experiment 2, we explored whether sex steroids contribute to this relation between pubertal maturation and alcohol use by examining the association between salivary sex steroid levels and alcohol use in 168 adolescents (86 boys). It was found that, when controlling for age, advanced pubertal maturation is related to increased alcohol use in adolescent boys and girls. Controlling for age, higher testosterone and estradiol levels correlated with the onset of alcohol use in boys. In addition, higher estradiol levels were associated with a larger quantity of alcohol use in boys. Correlations between sex steroids and alcohol use were not significant in girls. These findings show that advanced pubertal maturation is related to advanced alcohol use, and that higher sex steroid levels could be one of the underlying mechanisms of this relation in boys. Sex steroids might promote alcohol use by stimulating brain regions implicated in reward processing.

  3. Pubertal maturation and programming of hypothalamic-pituitary-adrenal reactivity.

    PubMed

    Romeo, Russell D

    2010-04-01

    Modifications in neuroendocrine function are a hallmark of pubertal development. These changes have many short- and long-term implications for the physiological and neurobehavioral function of an individual. The purpose of the present review is to discuss our current understanding of how pubertal development and stress interact to affect the hypothalamic-pituitary-adrenal (HPA) axis, the major neuroendocrine axis that controls the hormonal stress response. A growing body of literature indicates that puberty is marked by dramatic transitions in stress reactivity. Moreover, recent studies indicate that exposure to stressors during pubertal maturation may result in enduring changes in HPA responsiveness in adulthood. As puberty is marked by a substantial increase in many stress-related psychological and physiological disorders (e.g., depression, anxiety, drug abuse), it is essential to understand the factors that regulate and modulate HPA function during this crucial period of development.

  4. Genetic and Environmental Influences on the Association between Pubertal Maturation and Internalizing Symptoms

    ERIC Educational Resources Information Center

    Marceau, Kristine; Neiderhiser, Jenae M.; Lichtenstein, Paul; Reiss, David

    2012-01-01

    The literature consistently shows an association between pubertal maturation and internalizing problems in girls. The association for boys is less clear. The present study examines genetic and environmental influences on the association between pubertal maturation and internalizing problems for boys and girls in two primarily Caucasian adolescent…

  5. Animal Modeling of Early Programming and Disruption of Pubertal Maturation.

    PubMed

    Castellano, Juan M; Tena-Sempere, Manuel

    2016-01-01

    Puberty is a fascinating developmental transition that gates the attainment of reproductive capacity and culminates the somatic and sexual maturation of the organism. Rather than a circumscribed phenomenon, puberty is the endpoint of a long-lasting developmental continuum, which initiates in utero. Besides important genetic determinants, the tempo of puberty is influenced by numerous endogenous and exogenous factors that, acting at different levels of the developing hypothalamic-pituitary-gonadal (HPG) axis along the maturational continuum indicated above, can influence puberty onset. Among the different modifiers of puberty, in this chapter we will focus our attention on two major groups of signals, sex steroids and nutritional cues, and how these interplay mostly with the central elements of the HPG axis, and especially with gonadotropin-releasing hormone neurons and their key upstream afferents, Kiss1 neurons, to influence the timing of puberty. Special emphasis will be given to summarize information emerging from relevant preclinical (mostly rodent) animal models, and how this information might be relevant in terms of translational medicine, as it may help for a better understanding and eventually management of pubertal disorders of escalating prevalence worldwide.

  6. Sport training and the growth and pubertal maturation of young athletes.

    PubMed

    Matina, Robert M; Rogol, Alan D

    2011-09-01

    Growth and pubertal maturation of youth athletes are overwhelmingly within the broad range of normal variability. These include many successful male athletes who mature earlier than average, and many successful female athletes, especially in the "aesthetic" sports (artistic gymnastics, ice-skating, ballet) and distance running, who mature later than average. Artistic gymnasts generally receive the most attention, but their growth and maturation characteristics fall largely within the physiologic range and are indistinguishable from short, late maturing girls. It is difficult to ascribe causality to intensive training for sport as a factor in the later pubertal maturation of heavily training athletes. The alterations in hypothalamic-pituitary function for the GH/IGF-I and gonadal axes are likely appropriate for the stage of adolescent maturation. The selection and sorting processes for elite sport, including ballet, need critical evaluation. If intensive training is a factor affecting growth and pubertal maturation, its effects must be partitioned from (a) other factors known to influence these biological processes, and (b) other components of the overall sport training environment before causality can be established. Other factors which play an indeterminate role include: genetics/epigenetics, stress, psychosocial interactions, family environment and caloric intake, among others. These factors together with the energy expenditure of intensive training may influence the growth and pubertal maturation of some adolescent athletes. The effect is not necessarily attributable to training per se; rather, it is likely embedded in the elite sport training environment which is essentially an adult dominated enterprise.

  7. Synchronization in Ratings of Pubertal Maturity and Faulty Beliefs about Family Relationships.

    ERIC Educational Resources Information Center

    Papini, Dennis R.; Micka, Jill C.

    1991-01-01

    Examined the possibility that the degree of synchronization between parent and adolescent ratings of pubertal maturity is related to faulty beliefs about interpersonal relationships in the family. Results indicated that adolescent-parent synchrony affected adolescents' faulty beliefs. Mothers' endorsement of faulty beliefs was related to…

  8. Parental Knowledge is a Contextual Amplifier of Associations of Pubertal Maturation and Substance Use.

    PubMed

    Marceau, Kristine; Abar, Caitlin C; Jackson, Kristina M

    2015-09-01

    Earlier pubertal development and less parental knowledge have been linked to more substance use during adolescence. The present study examines interactions between pubertal timing and tempo and parental knowledge (children's disclosure, parental control, and parental solicitation) for adolescent substance initiation. Data are from a northeastern US-based cohort-sequential study examining 1023 youth (52 % female) semiannually for up to 6 assessments (ages 10.5-19 years). The findings supported the hypothesis that lower knowledge is a contextual amplifier of early timing-substance use associations in girls and later timing/slower tempo-substance use associations in boys, though results varied based on source of knowledge. The findings suggest that prevention efforts may have the greatest impact when targeting families of early developing girls, and later developing boys, and that incorporating a focus on specific sources of knowledge depending on the pubertal maturation profile of the adolescent may prove valuable in prevention/intervention efforts.

  9. Facial preferences in early adolescent girls: pubertal maturity predicts preferences maturity.

    PubMed

    Kościński, Krzysztof

    2013-09-01

    Despite numerous studies on perception of facial attractiveness in adults, preferences in adolescents remain poorly recognized. The aim of present study was to explore facial preferences in girls at early adolescence (11-14 years old) and compare them with preferences of women. All females evaluated the same 30 male faces, which were also assessed by independent judges for several perceived features. Regardless of age, girls assessed attractiveness much the same as women, and the strengths of their preferences for specific facial features were similar to those of women. Except for the youngest girls, pubertal maturity (measured as the time elapsed since the menarche and breast development) correlated positively with the similarity of the girls' attractiveness evaluations to those of adult women and with strength of preference for cues to good biological quality (skin healthiness and sexy appearance). This remained true even after controlling for age and psychosexual development, suggesting thus that sex hormones are involved in development of facial preferences in pubescent girls. PMID:24308210

  10. Pubertal hormones, the adolescent brain, and the maturation of social behaviors: Lessons from the Syrian hamster.

    PubMed

    Schulz, Kalynn M; Sisk, Cheryl L

    2006-07-25

    Conventional wisdom holds that gonadal steroid hormones organize and sexually differentiate neural circuits perinatally, and at puberty they activate these circuits to facilitate expression of social behaviors. Using the Syrian hamster to study the role of pubertal hormones in behavioral maturation, we have found that pubertal hormones also organize the adolescent brain. Initial studies revealed that male reproductive behavior cannot be activated by gonadal steroids prepubertally, indicating that the brain acquires behavioral responsiveness during adolescence. Subsequent experiments demonstrated that the presence of gonadal hormones during adolescence masculinize and defeminize behavioral responses of males to hormones in adulthood. Preliminary data also suggest that ovarian hormones defeminize but do not masculinize behavioral responses of females to hormones in adulthood. Furthermore, pubertal hormones program the adult expression of agonistic behaviors that are both steroid-dependent and steroid-independent in adulthood. Thus, the interaction between pubertal hormones and the adolescent brain is key for the maturation of adult social behaviors, and perturbations in the timing of this interaction have long-lasting consequences on adult behavior.

  11. Growth, pubertal development, skeletal maturation and bone mass acquisition in athletes.

    PubMed

    Georgopoulos, Neoklis A; Markou, Kostas B; Theodoropoulou, Anastasia; Vagenakis, George A; Mylonas, Panagiotis; Vagenakis, Apostolos G

    2004-01-01

    The genetic potentials for growth can be fully expressed only under favourable environmental conditions. Excessive physical training may negatively affect growth, especially during puberty. Sports that require a strict control of energy input in the presence of a high energy output are of particular concern. In gymnastics, a different pattern in skeletal maturation was observed, leading to an attenuation of growth potential ins Artistic Gymnasts (AG), more pronounced in males than in females, whereas in female Rhythmic Gymnasts (RG) the genetic predisposition to growth was preserved because of a late catch-up growth phenomenon. In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented. Intensive physical training and negative energy balance modify the hypothalamic pituitary set point at puberty, prolong the prepubertal stage and delay pubertal development and menarche in a variety of sports. In elite RG and AG the prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, paralleling the bone age rather than the chronological age. Bone formation, and, consequently, BMD are enhanced by physical activity. In athletes, high-impact loading activities have been shown to improve BMD, while in sports requiring a lean somatotype, the delay in skeletal maturation and pubertal development, resulting from hypoestrogenemia, predisposes athletes to osteopenia. In AG, an increase in bone density is observed using the bone age as denominator.

  12. Heightened stress responsivity and emotional reactivity during pubertal maturation: Implications for psychopathology.

    PubMed

    Spear, Linda Patia

    2009-01-01

    This commentary reviews and reflects on the studies of this special section: studies that collectively provide compelling evidence for meaningful changes in stress- and emotionally reactive psychophysiological systems with the transition from middle childhood into adolescence. The observed changes were complex and often overlaid upon ontogenetic differences in basal levels of activation of these systems. Maturational increases in responsiveness to stressors were stressor dependent and differentially expressed across autonomic and hormonal measures. Pubertal status increased the impact of some affective valence manipulations, although not significantly influencing others, including negative affect-related potentiation of startle/reflexes. Such ontogenetic increases in stressor and affect sensitivity may have implications for developmental psychopathology. Developmental increases in stressor reactivity may normally aid youth in responding adaptively to the challenges of adolescence, but may result in stress dysregulation among at-risk adolescents, increasing further their vulnerability for psychopathology. Pubertal-related increases in sensitivity to emotionally laden stimuli may exacerbate individual predispositions for exaggerated affective processing, perhaps contributing to the emergence of psychological disorders in these youth. Together, these studies, with their innovative use of autonomic, reflexive, and hormonal measures to index age- and pubertal-related changes in reactivity to stressors and affective stimuli, provide promising directions for future research. Some of these, along with a few cautionary notes, are outlined.

  13. Parental Knowledge is a Contextual Amplifier of Associations of Pubertal Maturation and Substance Use

    PubMed Central

    Marceau, Kristine; Abar, Caitlin C.; Jackson, Kristina M.

    2015-01-01

    Earlier pubertal development and less parental knowledge have been linked to more substance use during adolescence. The present study examines interactions between pubertal timing and tempo and parental knowledge (children’s disclosure, parental control, and parental solicitation) for adolescent substance initiation. Data are from a northeastern US-based cohort-sequential study examining 1023 youth (52% female) semiannually for up to 6 assessments (ages 10.5 to 19 years). The findings supported the hypothesis that lower knowledge is a contextual amplifier of early timing-substance use associations in girls and later timing/slower tempo-substance use associations in boys, though results varied based on source of knowledge. The findings suggest that prevention efforts may have the greatest impact when targeting families of early developing girls, and later developing boys, and that incorporating a focus on specific sources of knowledge depending on the pubertal maturation profile of the adolescent may prove valuable in prevention/intervention efforts. PMID:26208832

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

    ERIC Educational Resources Information Center

    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…

  15. An Exploratory Study of Pubertal Maturation Timing and Self-Esteem among Gay and Bisexual Male Youths.

    ERIC Educational Resources Information Center

    Savin-Williams, Ritch C.

    1995-01-01

    A study of 83 gay and bisexual male youths (17-23 years old) found that pubertal maturation was associated with self-reported age of first orgasm and homosexual activity and frequency of orgasms during junior high school. It concluded that gay and bisexual male youths share with heterosexual male youths a similar developmental trajectory in regard…

  16. Neonatal amygdala lesions advance pubertal timing in female rhesus macaques

    PubMed Central

    Stephens, Shannon B.Z.; Raper, Jessica; Bachevalier, Jocelyne; Wallen, Kim

    2014-01-01

    Summary Social context influences the timing of puberty in both humans and nonhuman primates, such as delayed first ovulation in low-ranking rhesus macaques, but the brain region(s) mediating the effects of social context on pubertal timing are unknown. The amygdala is important for responding to social information and thus, is a potential brain region mediating the effects of social context on pubertal timing. In this study, female rhesus macaques living in large, species-typical, social groups received bilateral neurotoxic amygdala lesions at one month of age and pubertal timing was examined beginning at 14 months of age. Pubertal timing was affected in neonatal amygdala-lesioned females (Neo-A), such that they experienced significantly earlier menarche and first ovulation than did control females (Neo-C). Duration between menarche and first ovulation did not differ between Neo-A and Neo-C females, indicating earlier first ovulation in Neo-A females was likely a consequence of earlier menarche. Social rank of Neo-A females was related to age at menarche, but not first ovulation, and social rank was not related to either event in Neo-C females. It is more likely that amygdalectomy affects pubertal timing through its modulation of GABA-ergic mechanisms rather than as a result of the removal of a social-contextual inhibition on pubertal timing. PMID:25462903

  17. Body fat mass, body fat distribution, and pubertal development: a longitudinal study of physical and hormonal sexual maturation of girls.

    PubMed

    de Ridder, C M; Thijssen, J H; Bruning, P F; Van den Brande, J L; Zonderland, M L; Erich, W B

    1992-08-01

    The rate at which girls progress through the stages of puberty in relation to body fat mass and body fat distribution and its relation to their hormonal profiles was studied. Sixty-eight schoolgirls participated in a longitudinal study during 3 yr. The girls were divided into subgroups with increasing skinfold thicknesses and waist-hip ratio. They were also grouped depending on Tanner's breast development classification (M2 and M3). The age at M2 was only marginally correlated with the menarcheal age, but the age at M2 and the time interval from that age to menarche was negatively correlated. Age at the onset of puberty was not related to body fat mass or distribution. The rate of pubertal development after pubertal stage M3 was negatively related to the body fat mass. Age at M2 was only correlated with estrone (E1), while the rate of pubertal development was associated with higher FSH, E1, estradiol (E2), the fraction of E2 that was not bound to sex-hormone-binding globulin (non-sex-hormone-binding globulin bound E2) and androstenedione plasma levels at the onset of puberty. Body fat distribution, rather than body fat mass was related to the total and the non-sex-hormone-binding globulin bound plasma levels of E2 and testosterone at the onset of puberty. Changes in body fat distribution in early female puberty were chiefly related to the waist circumferences. We found no evidence that body fat mass or body fat distribution triggers the onset of puberty. Body fat distribution was related to early pubertal endocrine activity. Body fat mass was negatively related to the rate of pubertal development toward menarche, but no clear indications for an endocrine-related process is found. We conclude that onset of puberty and menarche are not parallel pubertal events, and that early pubertal plasma E1, E2 and androstenedione levels are predictors for the rate of pubertal development toward menarche. We propose that the control of the onset of puberty and maturation of the

  18. Role of endogenous opiates in pubertal maturation: opposing actions of naltrexone in prepubertal and late pubertal boys.

    PubMed

    Mauras, N; Veldhuis, J D; Rogol, A D

    1986-06-01

    Despite the acute enhancement of gonadotropin output that occurs in the presence of opiate blockade in sexually immature rats and adult men, studies thus far have not demonstrated a role for endogenous opioid peptides during pubertal development in the human. We studied 15 normal boys, 5 sexually developed (Tanner stages IV-V) and 10 sexually infantile, before and after chronic (1-month) administration of a selective micromicron-opiate-receptor antagonist (naltrexone). Gonadotropin secretion was assessed by repetitive venous sampling for 24 h to appraise the pulsatile features of LH release as well as by graded serum LH responses to GnRH. Using an objective pulse detection method, we found that 1) in response to naltrexone, pubertal boys had significantly higher LH pulse frequency (P = 0.044), mean LH concentration (P = 0.0325), and area under the LH vs. time curve (P = 0.0325) compared to those in the basal state; and 2) in sexually immature individuals, naltrexone significantly decreased LH pulse frequency (P = 0.014), mean LH concentration (P = 0.049), and absolute LH peak concentration (P = 0.039) compared to those in the basal state. We suggest that the paradoxical inhibitory response to naltrexone in prepubertal boys represents an agonist-like effect of chronic naltrexone administration. This consideration implies that opiate neural pathways are responsive if not highly sensitive to the agonist effect of opiate substances in the prepubertal male. Accordingly, physiological pubertal progression may be accompanied by decreased sensitivity of the hypothalamic gonadostat to the inhibitory effects of opioid peptides. PMID:3517031

  19. A Comparison of Self-Reported Puberty Using the Pubertal Development Scale and the Sexual Maturation Scale in a School-Based Epidemiologic Survey

    ERIC Educational Resources Information Center

    Bond, Lyndal; Clements, Jackie; Bertalli, Nadine; Evans-Whipp, Tracy; McMorris, Barbara J.; Patton, George C.; Toumbourou, John W.; Catalano, Richard F.

    2006-01-01

    Purpose: To examine concordance between two self-reported measures of puberty: Sexual Maturation Scale (SMS) and Pubertal Development Scale (PDS) and their acceptability to adolescents. Methods: Participants of a school-based study in grades 5, 7 and 9 were classified into one of 5 pubertal stages using each method. Results: 2864 students (age…

  20. Brief communication: a proposed method for the assessment of pubertal stage in human skeletal remains using cervical vertebrae maturation.

    PubMed

    Shapland, Fiona; Lewis, Mary E

    2014-01-01

    The assessment of age-at-death in non-adult skeletal remains is under constant review. However, in many past societies an individual's physical maturation may have been more important in social terms than their exact age, particularly during the period of adolescence. In a recent article (Shapland and Lewis: Am J Phys Anthropol 151 (2013) 302-310) highlighted a set of dental and skeletal indicators that may be useful in mapping the progress of the pubertal growth spurt. This article presents a further skeletal indicator of adolescent development commonly used by modern clinicians: cervical vertebrae maturation (CVM). This method is applied to a collection of 594 adolescents from the medieval cemetery of St. Mary Spital, London. Analysis reveals a potential delay in ages of attainment of the later CVM stages compared with modern adolescents, presumably reflecting negative environmental conditions for growth and development. The data gathered on CVM is compared to other skeletal indicators of pubertal maturity and long bone growth from this site to ascertain the usefulness of this method on archaeological collections.

  1. Mothers' Knowledge of Early Adolescents' Activities following the Middle School Transition and Pubertal Maturation

    ERIC Educational Resources Information Center

    Laird, Robert D.; Marrero, Matthew D.

    2011-01-01

    This study tested a sequential mediation model to determine whether experiences, social cognitions, or parent-adolescent interactional processes account for lower levels of mothers' knowledge of adolescents' whereabouts and activities following early adolescents' transition into middle school (MS) and pubertal development. Cross-sectional data…

  2. Timing of Pubertal Maturation in Girls: An Integrated Life History Approach

    ERIC Educational Resources Information Center

    Ellis, Bruce J.

    2004-01-01

    Life history theory provides a metatheoretical framework for the study of pubertal timing from an evolutionary-developmental perspective. The current article reviews 5 middle-level theories-energetics theory, stress-suppression theory, psychosocial acceleration theory, paternal investment theory, and child development theory-each of which applies…

  3. The Relationship between Greater Pre-Pubertal Adiposity, Subsequent Age of Maturation and Bone Strength during Adolescence†

    PubMed Central

    Glass, Natalie A.; Torner, James C.; Letuchy, Elena M.; Burns, Trudy L.; Janz, Kathleen F.; Gilmore, Julie M. Eichenberger; Schlechte, Janet A.; Levy, Steven M.

    2016-01-01

    This longitudinal study investigated whether greater pre-pubertal adiposity was associated with subsequent timing of maturation and bone strength during adolescence in 135 girls and 123 boys participating in the Iowa Bone Development Study. Greater adiposity was defined using BMI data at age 8 years to classify participants as overweight (OW, ≥85th percentile for age and sex) or healthy-weight, HW). Maturation was defined as the estimated age of peak height velocity (PHV) based on a series of cross-sectional estimates. Measurements were taken at ages 11, 13, 15 and 17 years for estimates of body composition by DXA, bone compression (bone strength index) and torsion strength (polar strength-strain index) at the radius and tibia by pQCT, and femoral neck bending strength (section modulus) by hip structural analysis. Bone strength in OW versus HW were evaluated by fitting sex-specific linear mixed models that included centered age (visit age – grand mean age of cohort) as the time variable and adjusted for change in fat mass, and limb length in Model 1. Analyses were repeated using biological age (visit age – age PHV) as the time variable for Model 1 with additional adjustment for lean mass in Model 2. BMI was negatively associated with age of maturation (p<0.05). OW versus HW girls had significantly greater bone strength (p<0.001) in Model 1, while OW versus HW boys had significantly greater bone strength (p<0.001) at the tibia and femoral neck, but not radius (p>0.05). Analyses were repeated using biological age, which yielded reduced parameter estimates for girls but similar results for boys (Model 1.) Differences were no longer present following adjustment for lean mass (Model 2) in girls (p>0.05) while differences at the tibia were sustained in boys (p<0.05). These findings demonstrate sex- and site-specific differences in the associations between adiposity, maturation and bone strength. PMID:26861036

  4. Maturity Model for Advancing Smart Grid Interoperability

    SciTech Connect

    Knight, Mark; Widergren, Steven E.; Mater, J.; Montgomery, Austin

    2013-10-28

    Abstract—Interoperability is about the properties of devices and systems to connect and work properly. Advancing interoperability eases integration and maintenance of the resulting interconnection. This leads to faster integration, lower labor and component costs, predictability of projects and the resulting performance, and evolutionary paths for upgrade. When specifications are shared and standardized, competition and novel solutions can bring new value streams to the community of stakeholders involved. Advancing interoperability involves reaching agreement for how things join at their interfaces. The quality of the agreements and the alignment of parties involved in the agreement present challenges that are best met with process improvement techniques. The GridWise® Architecture Council (GWAC) sponsored by the United States Department of Energy is supporting an effort to use concepts from capability maturity models used in the software industry to advance interoperability of smart grid technology. An interoperability maturity model has been drafted and experience is being gained through trials on various types of projects and community efforts. This paper describes the value and objectives of maturity models, the nature of the interoperability maturity model and how it compares with other maturity models, and experiences gained with its use.

  5. The impact of paternal alcoholism and maternal social position on boys' school adjustment, pubertal maturation and sexual behavior: a test of two competing hypotheses.

    PubMed

    Malo, J; Tremblay, R E

    1997-02-01

    Two competing hypotheses concerning the effects of stressful environments on the onset of puberty were tested using longitudinal data for a sample of boys from low socioeconomic backgrounds. Paternal alcoholism and maternal social position were used as indicators of family stress. School placement was monitored from school entry to 14 years of age. Teachers rated the boys' disruptive and anxious behaviors, while the boys reported on parenting behaviors at 10 years of age. Pubertal maturation, age of first sexual intercourse and sexual behavior were assessed between 11 and 14 years of age. The prepubertal data indicated that boys with an alcoholic father, or a mother from a low social position, were more stressed and had more behavior problems: the boys with alcoholic fathers perceived their parents as being more punitive, and as setting fewer rules concerning their behavior; those who had at least one maladjusted parent were more often placed out of an age-appropriate regular classroom, and were rated more disruptive and more anxious by their teachers. Paradoxically, the results for the onset of puberty gave support to the two rival hypotheses. Paternal alcoholism led to a delay of male pubertal onset, as suggested by the hypothesis that stress activates the hypothalamic-pituitary-adrenal axis, and inhibits the hypothalamic-pituitary-gonadal axis. However, sons of alcoholic fathers had more frequent sexual intercourse and more sexual partners, as suggested by the evolutionary theory of socialization. High maternal social position acted as a protective factor for school placement of boys with an alcoholic father. These results challenged a key hypothesis of the evolutionary theory of socialization for males. They indicated that the link between childhood family environment, behavior development, pubertal maturation and sexual promiscuity are more complex than anticipated.

  6. Advanced Stirling Convertor (ASC) Technology Maturation

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Wilson, Scott; Collins, Josh; Wilson, Kyle

    2016-01-01

    The Advanced Stirling Convertor (ASC) development effort was initiated by NASA Glenn Research Center with contractor Sunpower, Inc., to develop high-efficiency thermal-to-electric power conversion technology for NASA Radioisotope Power Systems (RPSs). Early successful performance demonstrations led to the expansion of the project as well as adoption of the technology by the Department of Energy (DOE) and system integration contractor Lockheed Martin Space Systems Company as part of the Advanced Stirling Radioisotope Generator (ASRG) flight project. The ASRG integrates a pair of ASCs to convert the heat from a pair of General Purpose Heat Source (GPHS) modules into electrical power. The expanded NASA ASC effort included development of several generations of ASC prototypes or engineering units to help prepare the ASC technology and Sunpower for flight implementation. Sunpower later had two parallel contracts allowing the last of the NASA engineering units called ASC-E3 to serve as pathfinders for the ASC-F flight convertors being built for DOE. The ASC-E3 convertors utilized the ASC-F flight specifications and were built using the ASC-F design and process documentation. Shortly after the first ASC-F pair achieved initial operation, due to budget constraints, the DOE ASRG flight development contract was terminated. NASA continues to invest in the development of Stirling RPS technology including continued production of the ASC-E3 convertors, seven of which have been delivered with one additional unit in production. Starting in fiscal year 2015, Stirling Convertor Technology Maturation has been reorganized as an element of the RPS Stirling Cycle Technology Development (SCTD) Project and long-term plans for continued Stirling technology advancement are in reformulation. This paper provides a status on the ASC project, an overview of advancements made in the design and production of the ASC at Sunpower, and a summary of acceptance tests, reliability tests, and tactical

  7. Advanced Stirling Convertor (ASC) Technology Maturation

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Wilson, Scott; Collins, Josh; Wilson, Kyle

    2015-01-01

    The Advanced Stirling Convertor (ASC) development effort was initiated by NASA Glenn Research Center (GRC) with contractor Sunpower Inc. to develop high efficiency thermal-to-electric power conversion technology for NASA Radioisotope Power Systems. Early successful performance demonstrations led to the expansion of the project as well as adoption of the technology by the Department of Energy (DOE) and system integration contractor Lockheed Martin Space Systems Company as part of the Advanced Stirling Radioisotope Generator (ASRG) flight project. The ASRG integrates a pair of ASCs to convert the heat from a pair of General Purpose Heat Source (GPHS) modules into electrical power. The expanded NASA ASC effort included development of several generations of ASC prototypes or Engineering Units to help prepare the ASC technology and Sunpower for flight implementation. Sunpower later had two parallel contracts allowing the last of the NASA Engineering Units called ASC-E3 to serve as pathfinders for the ASC-F flight convertors being built for DOE. The ASC-E3 convertors utilized the ASC-F flight specifications and were built using the ASC-F design and process documentation. Shortly after the first ASC-F Pair achieved initial operation, due to budget constraints, the DOE ASRG flight development contract was terminated. NASA continues to invest in the development of Stirling RPS technology including continued production of the ASC-E3 convertors, seven of which have been delivered with one additional unit in production. Starting in FY2015, Stirling Convertor Technology Maturation has been reorganized as an element of the RPS Stirling Cycle Technology Development (SCTD) Project and long-term plans for continued Stirling technology advancement are in reformulation. This paper provides a status on the ASC project, an overview of advancements made in the design and production of the ASC at Sunpower, and a summary of acceptance tests, reliability tests, and tactical tests at NASA

  8. Development's Tortoise and Hare: Pubertal Timing, Pubertal Tempo, and Depressive Symptoms in Boys and Girls

    ERIC Educational Resources Information Center

    Mendle, Jane; Harden, K. Paige; Brooks-Gunn, Jeanne; Graber, Julia A.

    2010-01-01

    Although the sequence of pubertal maturation remains consistent across most individuals, the timing and tempo of development fluctuate widely. While past research has largely focused on the sequelae of pubertal timing, a faster tempo of maturation might also present special challenges to children for acclimating to new biological and social…

  9. Nutrition and pubertal development

    PubMed Central

    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 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. PMID:25538876

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

    PubMed Central

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

    2015-01-01

    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. PMID:24795438

  11. Disorders of pubertal development: precocious puberty.

    PubMed

    Kakarla, Nirupama; Bradshaw, Karen D

    2003-11-01

    Puberty is a complex developmental process culminating in sexual maturity. This transitional period begins in late childhood and is characterized by maturation of the hypothalamic-pituitary-gonadal axis, the appearance of secondary sexual characteristics, acceleration of growth, and, ultimately, the capacity for fertility. Significant endocrinologic changes accompany these developmental events. Disorders of pubertal development may occur at any of the steps of the maturational process leading to either precocious or delayed puberty. A thorough understanding of the normal pubertal process is important to the accurate diagnosis and treatment of pubertal disorders.

  12. Preadolescent and adolescent endocrinology: physiology and physiopathology. II. Hormonal changes during abnormal pubertal development.

    PubMed

    Sizonenko, P C

    1978-08-01

    Based on the knowledge of the physiology of regulation of gonadotropins and gonadal steroids, basal levels of these hormones might be indicative of the etiologic factors of abnormal pubertal development. In addition, stimulatory tests may help in the diagnosis of such conditions. It is interesting that the pubertal maturation of the adrenal cortex is independent of the hypothalamic-pituitary-gonadal axis. The role of the adrenal cortex for the pubertal development remains questionable: adrenal androgens are low in isosexual precocious puberty, low in delayed adolescence, and normal in hyper- or hypogonadotropic hypogonadism. The importance of this role is doubled in congenital virilizing adrenal hyperplasia. When the disease is untreated, although adrenal androgens in excess advance bone age and hypothalamic maturation, girls remain prepubertal. When the therapeutic control is good, normal puberty occurs. The action of the adrenal androgens on growth and puberty remains to be determined.

  13. Contribution of anthropometric characteristics to pubertal stage prediction in young male individuals☆

    PubMed Central

    Medeiros, Radamés Maciel Vitor; Arrais, Ricardo Fernando; de Azevedo, Jenner Chrystian Veríssimo; do Rêgo, Jeferson Tafarel Pereira; de Medeiros, Jason Azevedo; de Andrade, Ricardo Dias; Dantas, Paulo Moreira Silva

    2014-01-01

    Objective: To identify the contribution of anthropometric variables to predict the maturational stage in young males. Methods: Cross-sectional study that enrolled 190 male subjects aged between eight and 18 years, randomly selected from public and private schools in Natal, Northeast Brazil. Thirtytwo anthropometric variables were measured following the recommendations of the International Society for the Advancement of Kineanthropometry (ISAK). The assessment of sexual maturation was based on the observation of two experienced experts, who identified the pubertal development according to Tanner guidelines (1962). Results: The anthropometric variables showed a significant increase of their values during the advancement of pubertal development (p<0.05). The following variables showed the best value for prediction of maturational groups: sitting height, femoral biepicondylar diameter, forearm girth, triceps skinfold, tibiale laterale and acromiale-radiale bonelenghts. These variables were able to estimate the pubertal stages in 76.3% of the sujects. Conclusion: The anthropometric characteristics showed significant differences between the moments of maturational stages, being found, representatively, seven variables that best predict the stages of sexual maturation. PMID:25479854

  14. Pubertal development and regulation.

    PubMed

    Abreu, Ana Paula; Kaiser, Ursula B

    2016-03-01

    Puberty marks the end of childhood and is a period when individuals undergo physiological and psychological changes to achieve sexual maturation and fertility. The hypothalamic-pituitary-gonadal axis controls puberty and reproduction and is tightly regulated by a complex network of excitatory and inhibitory factors. This axis is active in the embryonic and early postnatal stages of life and is subsequently restrained during childhood, and its reactivation culminates in puberty initiation. The mechanisms underlying this reactivation are not completely known. The age of puberty onset varies between individuals and the timing of puberty initiation is associated with several health outcomes in adult life. In this Series paper, we discuss pubertal markers, epidemiological trends of puberty initiation over time, and the mechanisms whereby genetic, metabolic, and other factors control secretion of gonadotropin-releasing hormone to determine initiation of puberty.

  15. Cognitive Function in Individuals with Atypical Pubertal Development.

    ERIC Educational Resources Information Center

    Rovet, Joanne F.; And Others

    A study of 55 growth-disturbed children, aged 8-17, was conducted to assess how rate of physical maturation and pubertal development influences cognitive and neuropsychological functioning. The sample included 27 boys with short stature and delayed pubertal development (SSB), 15 girls with delayed puberty (DPG), and 13 girls with precocious…

  16. Advanced Stirling Convertor (ASC) Technology Maturation in Preparation for Flight

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Cornell, Peggy A.

    2012-01-01

    The Advanced Stirling Convertor (ASC) is being developed by an integrated team of Sunpower and National Aeronautics and Space Administration s (NASA s) Glenn Research Center (GRC). The ASC development, funded by NASA s Science Mission Directorate, started as a technology development effort in 2003 and has since evolved through progressive convertor builds and successful testing to demonstrate high conversion efficiency, low mass, and capability to meet long-life Radioisotope Power System (RPS) requirements. The technology has been adopted by the Department of Energy and Lockheed Martin Space Systems Company s Advanced Stirling Radioisotope Generator (ASRG), which has been selected for potential flight demonstration on Discovery 12. This paper provides an overview of the status of ASC development including the most recent ASC-E2 convertors that have been delivered to GRC and an introduction to the ASC-E3 and ASC flight convertors that Sunpower will build next. The paper also describes the technology maturation and support tasks being conducted at GRC to support ASC and ASRG development in the areas of convertor and generator extended operation, high-temperature materials, heater head life assessment, organics, nondestructive inspection, spring fatigue testing, and other reliability verification tasks.

  17. Pubertal Development: Correspondence between Hormonal and Physical Development

    ERIC Educational Resources Information Center

    Shirtcliff, Elizabeth A.; Dahl, Ronald E.; Pollak, Seth D.

    2009-01-01

    Puberty is advanced by sex hormones, yet it is not clear how it is best measured. The interrelation of multiple indices of puberty was examined, including the Pubertal Development Scale (PDS), a picture-based interview about puberty (PBIP), and a physical exam. These physical pubertal measures were then associated with basal hormones responsible…

  18. Associations among Pubertal Development, Empathic Ability, and Neural Responses While Witnessing Peer Rejection in Adolescence

    ERIC Educational Resources Information Center

    Masten, Carrie L.; Eisenberger, Naomi I.; Pfeifer, Jennifer H.; Colich, Natalie L.; Dapretto, Mirella

    2013-01-01

    Links among concurrent and longitudinal changes in pubertal development and empathic ability from ages 10 to 13 and neural responses while witnessing peer rejection at age 13 were examined in 16 participants. More advanced pubertal development at age 13, and greater longitudinal increases in pubertal development, related to increased activity in…

  19. Genetic Influences on Pubertal Development and Links to Behavior Problems

    PubMed Central

    Beltz, Adriene M.; Wadsworth, Sally J.; Berenbaum, Sheri A.

    2016-01-01

    Genetic influences on adolescent psychological development are likely to be mediated and moderated by pubertal hormones. Combining genetic analyses with advanced models of pubertal development, we extended work on the measurement and psychological significance of puberty. We examined how genetic and environmental influences on puberty vary by the way that development is described (logistic versus linear models versus traditional methods) and the different aspects of puberty (adrenarche vs. gonadarche), and how genes and environment contribute to the covariation between different descriptions and aspects of puberty, and between pubertal development and behavior problems (substance use, age at sexual initiation). We also considered how puberty moderated the heritability of psychological outcomes (internalizing and externalizing problems), and sex differences. Participants from the Colorado Longitudinal Twin Study (403 girls, 395 boys) reported their pubertal development annually from ages 9 through 15; they and their parents reported their behavior in mid-to-late adolescence. There was a large genetic contribution to pubertal timing for both sexes no matter how it was measured, but findings for pubertal tempo varied by method. Genetic covariation accounted for most of the phenotypic correlations among different indicators of pubertal timing, and between pubertal timing and psychological outcome. We consider the implications of our results for understanding how pubertal hormones mediate or moderate genetic and environmental influences on psychological development. PMID:25903988

  20. Increased neural response to peer rejection associated with adolescent depression and pubertal development

    PubMed Central

    Siegle, Greg J.; Lee, Kyung Hwa; Nelson, Eric E.; Stroud, Laura R.; Dahl, Ronald E.

    2014-01-01

    Sensitivity to social evaluation has been proposed as a potential marker or risk factor for depression, and has also been theorized to increase with pubertal maturation. This study utilized an ecologically valid paradigm to test the hypothesis that adolescents with major depressive disorder (MDD) would show altered reactivity to peer rejection and acceptance relative to healthy controls in a network of ventral brain regions implicated in affective processing of social information. A total of 48 adolescents (ages 11–17), including 21 with a current diagnosis of MDD and 27 age- and gender-matched controls, received rigged acceptance and rejection feedback from fictitious peers during a simulated online peer interaction during functional neuroimaging. MDD youth showed increased activation to rejection relative to controls in the bilateral amygdala, subgenual anterior cingulate, left anterior insula and left nucleus accumbens. MDD and healthy youth did not differ in response to acceptance. Youth more advanced in pubertal maturation also showed increased reactivity to rejection in the bilateral amygdala/parahippocampal gyrus and the caudate/subgenual anterior cingulate, and these effects remained significant when controlling for chronological age. Findings suggest that increased reactivity to peer rejection is a normative developmental process associated with pubertal development, but is particularly enhanced among youth with depression. PMID:24273075

  1. Pubertal Development, Personality, and Substance Use: A 10-Year Longitudinal Study From Childhood to Adolescence

    PubMed Central

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

    2013-01-01

    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. PMID:24016016

  2. Nutritional and Pubertal Disorders.

    PubMed

    Muñoz-Calvo, M Teresa; Argente, Jesús

    2016-01-01

    Caloric-protein malnutrition can slow growth and cause pubertal delay. This chapter focuses on endocrine abnormalities and pubertal alterations in patients with eating disorders, childhood obesity, the female athlete triad and children cancer survivors. Patients with anorexia nervosa (AN) exhibit multiple endocrine abnormalities, including isolated hypogonadotropic hypogonadism. The delay in pubertal development and reduction in growth seen in AN patients may be a direct result of malnutrition. Appropriate psychiatric, nutritional and hormonal therapy is necessary. It is suggested that obesity during childhood can accelerate pubertal onset and these children usually exhibit accelerated linear growth during puberty. In girls the relationship between childhood obesity and early pubertal onset could be related to their insulin resistance and/or hyperinsulinemia. The female athlete triad is often observed in physically active girls and women in whom low energy availability with or without disordered eating, menstrual dysfunction and low bone mineral density can be present. In prepubertal girls excess exercise can cause delayed menarche with no effects on adult height, while in postpubertal females it results in menstrual cycle irregularities. The consequences of childhood cancer depend on the type of cancer, its location, the age at which the disease was diagnosed, the dose of radiotherapy, and the type and dose of chemotherapy. PMID:26680577

  3. Modeling Pubertal Timing and Tempo and Examining Links to Behavior Problems

    PubMed Central

    Beltz, Adriene M.; Corley, Robin P.; Bricker, Josh B.; Wadsworth, Sally J.; Berenbaum, Sheri A.

    2014-01-01

    Research on the role of puberty in adolescent psychological development requires attention to the meaning and measurement of pubertal development. Particular questions concern the utility of self report, the need for complex models to describe pubertal development, the psychological significance of pubertal timing versus tempo, and sex differences in the nature and psychological significance of pubertal development. We used longitudinal self-report data to model linear and logistic trajectories of pubertal development, and used timing and tempo estimates from these models, and from traditional approaches (age at menarche and time from onset of breast development to menarche), to predict psychological outcomes of internalizing and externalizing behavior problems, and early sexual activity. Participants (738 girls, 781 boys) reported annually from ages 9 through 15 on their pubertal development, and they and their parents reported on their behavior in mid-to-late adolescence and early adulthood. Self reports of pubertal development provided meaningful data for both boys and girls, producing good trajectories, and estimates of individuals’ pubertal timing and tempo. A logistic model best fit the group data. Pubertal timing was estimated to be earlier in the logistic compared to linear model, but linear, logistic, and traditional estimates of pubertal timing correlated highly with each other and similarly with psychological outcomes. Pubertal tempo was not consistently estimated, and associations of tempo with timing and with behavior were model dependent. Advances in modeling facilitate the study of some questions about pubertal development, but assumptions of the models affect their utility in psychological studies. PMID:25437757

  4. Modeling pubertal timing and tempo and examining links to behavior problems.

    PubMed

    Beltz, Adriene M; Corley, Robin P; Bricker, Josh B; Wadsworth, Sally J; Berenbaum, Sheri A

    2014-12-01

    Research on the role of puberty in adolescent psychological development requires attention to the meaning and measurement of pubertal development. Particular questions concern the utility of self-report, the need for complex models to describe pubertal development, the psychological significance of pubertal timing vs. tempo, and sex differences in the nature and psychological significance of pubertal development. We used longitudinal self-report data to model linear and logistic trajectories of pubertal development, and used timing and tempo estimates from these models, and from traditional approaches (age at menarche and time from onset of breast development to menarche), to predict psychological outcomes of internalizing and externalizing behavior problems, and early sexual activity. Participants (738 girls, 781 boys) reported annually from ages 9 through 15 on their pubertal development, and they and their parents reported on their behavior in mid-to-late adolescence and early adulthood. Self-reports of pubertal development provided meaningful data for both boys and girls, producing good trajectories, and estimates of individuals' pubertal timing and tempo. A logistic model best fit the group data. Pubertal timing was estimated to be earlier in the logistic compared to linear model, but linear, logistic, and traditional estimates of pubertal timing correlated highly with each other and similarly with psychological outcomes. Pubertal tempo was not consistently estimated, and associations of tempo with timing and with behavior were model dependent. Advances in modeling facilitate the study of some questions about pubertal development, but assumptions of the models affect their utility in psychological studies.

  5. Pubertal timing and adolescent sexual behavior in girls.

    PubMed

    Moore, Sarah R; Harden, K Paige; Mendle, Jane

    2014-06-01

    Girls who experience earlier pubertal timing relative to peers also exhibit earlier timing of sexual intercourse and more unstable sexual relationships. Although pubertal development initiates feelings of physical desire, the transition into romantic and sexual relationships involves complex biological and social processes contributing both to physical maturation and to individual interpretations of pubertal experiences. Using a sample of female sibling pairs (n = 923 pairs) from the National Longitudinal Study of Adolescent Health, the present study investigated associations among menarche and perceived pubertal timing, age of first sexual intercourse (AFI), and adolescent dating and sexual behavior using a behavioral genetic approach. Genetic factors influencing age at menarche and perceived pubertal timing predicted AFI through shared genetic pathways, whereas genetic factors related only to perceived pubertal timing predicted engagement in dating, romantic sex, and nonromantic sex in the previous 18 months. These results suggest that a girl's interpretation of her pubertal timing beyond objective timing is important to consider for the timing and the contexts of romantic and reproductive behavior.

  6. Usefulness and Reliability of Tanner Pubertal Self-Rating to Urban Black Adolescents in South Africa

    ERIC Educational Resources Information Center

    Norris, Shane A.; Richter, Linda M.

    2005-01-01

    Self-rating of pubertal development is the recommended method to assess puberty in large community-based surveys of adolescent development and behavior. The aim of this study was to validate for the first time pubertal self-assessment using the sexual maturation scale developed by Tanner among Black South African adolescents (n=182) aged between…

  7. The effects of gender and pubertal status on generalized joint laxity in young athletes.

    PubMed

    Quatman, Carmen E; Ford, Kevin R; Myer, Gregory D; Paterno, Mark V; Hewett, Timothy E

    2008-06-01

    Our purpose was to examine the effects of pubertal status on generalized joint laxity in a population of male and female athletes. We hypothesized that females would show higher generalized joint laxity after the onset of puberty while males would not. This cross-sectional cohort study included 275 female and 143 male middle school and high school basketball and soccer athletes. Joint laxity was assessed using the Beighton and Horan Joint Mobility Index. BHJMI scores were averaged and female and male athletes were compared by pubertal stage. Females demonstrated increased joint laxity scores between pre-pubertal and post-pubertal groups (P=0.042), while males did not. Pre-pubertal male and female athletes were not different in cumulative joint laxity scores (female pre-puberty mean=2.00; male pre-pubertal mean=1.66). However, following the onset of puberty females (pubertal mean=2.96; post-pubertal mean=3.03) demonstrated a greater joint laxity score compared to males (pubertal mean=1.24; post-pubertal mean=1.30). Gender differences in BHJMI score was found at puberty and post-puberty (P<0.001). In contrast to males, females may have greater generalized joint laxity following the onset of puberty. Structural and physiological changes that occur during puberty such as alterations in passive joint restraints, may affect the type, severity and incidence of injuries in the maturing adolescent population.

  8. In boys with abnormal developmental tempo, maturation of the skeleton and the hypothalamic-pituitary-gonadal axis remains synchronous.

    PubMed

    Flor-Cisneros, Armando; Leschek, Ellen W; Merke, Deborah P; Barnes, Kevin M; Coco, Marilena; Cutler, Gordon B; Baron, Jeffrey

    2004-01-01

    The primary mechanism that initiates puberty is unknown. One possible clue is that pubertal maturation often parallels skeletal maturation. Conditions that delay skeletal maturation also tend to delay the onset of puberty, whereas conditions that accelerate skeletal maturation tend to hasten the onset of puberty. To examine this relationship, we studied boys with congenital adrenal hyperplasia (n = 13) and familial male-limited precocious puberty (n = 22), two conditions that accelerate maturational tempo, and boys with idiopathic short stature (n = 18) in which maturational tempo is sometimes delayed. In all three conditions, the onset of central puberty generally occurred at an abnormal chronological age but a normal bone age. Boys with the greatest skeletal advancement began central puberty at the earliest age, whereas boys with the greatest skeletal delay began puberty at the latest age. Furthermore, the magnitude of the skeletal advancement or delay matched the magnitude of the pubertal advancement or delay. This synchrony between skeletal maturation and hypothalamic-pituitary-gonadal axis maturation was observed among patients within each condition and also between conditions. In contrast, the maturation of the hypothalamic-pituitary-gonadal axis did not remain synchronous with other maturational processes including weight, height, or body mass index. We conclude that in boys with abnormal developmental tempo, maturation of the skeleton and the hypothalamic-pituitary-gonadal axis remains synchronous. This synchrony is consistent with the hypothesis that in boys, skeletal maturation influences hypothalamic-pituitary-gonadal axis maturation.

  9. Shyness as a moderator of the link between advanced maturity and early adolescent risk behavior.

    PubMed

    Zalk, Nejra Van; Kerr, Margaret; Tilton-Weaver, Lauree

    2011-08-01

    Advanced maturity in early adolescence has previously been linked with several risk behaviors. In this study, we examine whether shyness and gender might moderate this link. The participants were 750 early adolescents (M(age) = 13.73; 390 girls and 360 boys), followed for one year. We conducted analyses with shyness and gender as moderators of the links between advanced maturity and different types of risk behavior, and between one risk behavior and another. Despite differential patterns for boys and girls, the results suggest that being shy or not being shy modifies the links between advanced maturity and risk behavior primarily for boys. For boys, shyness reduces relationships between advanced maturity and risk behavior, whereas not being shy exacerbates the relationships between advanced maturity and high-risk behavior. Controlling for romantic involvement and peer victimization did not alter the moderating effects, thus failing to support the idea that the weaker links for shy youths were due to shy youths not being drawn into advanced peer groups by romantic partners or peers. Thus, shyness might serve as a buffer against risk behavior in early adolescence.

  10. Pubertal timing and sexual risk behaviors among rural African American male youth: testing a model based on life history theory.

    PubMed

    Kogan, Steven M; Cho, Junhan; Simons, Leslie Gordon; Allen, Kimberly A; Beach, Steven R H; Simons, Ronald L; Gibbons, Frederick X

    2015-04-01

    Life History Theory (LHT), a branch of evolutionary biology, describes how organisms maximize their reproductive success in response to environmental conditions. This theory suggests that challenging environmental conditions will lead to early pubertal maturation, which in turn predicts heightened risky sexual behavior. Although largely confirmed among female adolescents, results with male youth are inconsistent. We tested a set of predictions based on LHT with a sample of 375 African American male youth assessed three times from age 11 to age 16. Harsh, unpredictable community environments and harsh, inconsistent, or unregulated parenting at age 11 were hypothesized to predict pubertal maturation at age 13; pubertal maturation was hypothesized to forecast risky sexual behavior, including early onset of intercourse, substance use during sexual activity, and lifetime numbers of sexual partners. Results were consistent with our hypotheses. Among African American male youth, community environments were a modest but significant predictor of pubertal timing. Among those youth with high negative emotionality, both parenting and community factors predicted pubertal timing. Pubertal timing at age 13 forecast risky sexual behavior at age 16. Results of analyses conducted to determine whether environmental effects on sexual risk behavior were mediated by pubertal timing were not significant. This suggests that, although evolutionary mechanisms may affect pubertal development via contextual influences for sensitive youth, the factors that predict sexual risk behavior depend less on pubertal maturation than LHT suggests. PMID:25501863

  11. Obesity and the pubertal transition in girls and boys

    PubMed Central

    Burt Solorzano, Christine M.; McCartney, Christopher R.

    2010-01-01

    Childhood obesity has become a major health concern in recent decades, especially with regard to metabolic abnormalities that impart a high risk for future cardiovascular disease. Recent data suggest that excess adiposity during childhood may influence pubertal development as well. In particular, excess adiposity during childhood may advance puberty in girls and delay puberty in boys. Obesity in peripubertal girls may also be associated with hyperandrogenemia and a high risk of adolescent polycystic ovary syndrome. How obesity may perturb various hormonal aspects of pubertal development remains unclear, but potential mechanisms are discussed herein. Insulin resistance and compensatory hyperinsulinemia may represent a common thread contributing to many of the pubertal changes reported to occur with childhood obesity. Our understanding of obesity’s impact on pubertal development is in its infancy, and more research into pathophysiological mechanisms and longer-term sequelae is important. PMID:20802107

  12. Associations of Peripubertal Serum Dioxin and Polychlorinated Biphenyl Concentrations with Pubertal Timing among Russian Boys

    PubMed Central

    Burns, Jane S.; Lee, Mary M.; Williams, Paige L.; Korrick, Susan A.; Sergeyev, Oleg; Lam, Thuy; Revich, Boris; Hauser, Russ

    2016-01-01

    Background: Dioxins, furans, and polychlorinated biphenyls (PCBs), dioxin-like and non-dioxin-like, have been linked to alterations in puberty. Objectives: We examined the association of peripubertal serum levels of these compounds [and their toxic equivalents (TEQs)] with pubertal onset and maturity among Russian boys enrolled at ages 8–9 years and followed prospectively through ages 17–18 years. Methods: At enrollment, 473 boys had serum dioxin-like compounds and PCBs measured. At the baseline visit and annually until age 17–18 years, a physician performed pubertal staging [genitalia (G), pubarche (P), and testicular volume (TV)]. Three hundred fifteen subjects completed the follow-up visit at 17–18 years of age. Pubertal onset was defined as TV > 3 mL, G2, or P2. Sexual maturity was defined as TV ≥ 20 mL, G5, or P5. Multivariable interval-censored models were used to evaluate associations of lipid-standardized concentrations with pubertal timing. Results: Medians (interquartile ranges) of the sum of dioxin-like compounds, TEQs, and non-dioxin-like PCBs were 362 pg/g lipid (279–495), 21.1 pg TEQ/g lipid (14.4–33.2), and 250 ng/g lipid (164–395), respectively. In adjusted models, the highest compared to lowest TEQ quartile was associated with later pubertal onset [TV = 11.6 months (95% CI: 3.8, 19.4); G2 = 10.1 months (95% CI: 1.4, 18.8)] and sexual maturity [TV = 11.6 months (95% CI: 5.7, 17.6); G5 = 9.7 months (95% CI: 3.1, 16.2)]. However, the highest compared to the lowest quartile of non-dioxin-like PCBs, when co-adjusted by TEQs, was associated with earlier pubertal onset [TV = –8.3 months (95% CI:–16.2, –0.3)] and sexual maturity [TV = –6.3 months (95% CI:–12.2, –0.3); G5 = –7.2 months (95% CI:–13.8, –0.6)]; the non-dioxin-like PCB associations were only significant when adjusted for TEQs. TEQs and PCBs were not significantly associated with pubic hair development. Conclusions: Our results suggest that TEQs may delay, while

  13. Bone Mineral Density in Healthy Female Adolescents According to Age, Bone Age and Pubertal Breast Stage

    PubMed Central

    Moretto, M.R; Silva, C.C; Kurokawa, C.S; Fortes, C.M; Capela, R.C; Teixeira, A.S; Dalmas, J.C; Goldberg, T.B

    2011-01-01

    Objectives: This study was designed to evaluate bone mineral density (BMD) in healthy female Brazilian adolescents in five groups looking at chronological age, bone age, and pubertal breast stage, and determining BMD behavior for each classification. Methods: Seventy-two healthy female adolescents aged between 10 to 20 incomplete years were divided into five groups and evaluated for calcium intake, weight, height, body mass index (BMI), pubertal breast stage, bone age, and BMD. Bone mass was measured by bone densitometry (DXA) in lumbar spine and proximal femur regions, and the total body. BMI was estimated by Quetelet index. Breast development was assessed by Tanner’s criteria and skeletal maturity by bone age. BMD comparison according to chronologic and bone age, and breast development were analyzed by Anova, with Scheffe’s test used to find significant differences between groups at P≤0.05. Results: BMD (g·cm-2) increased in all studied regions as age advanced, indicating differences from the ages of 13 to 14 years. This group differed to the 10 and 11 to 12 years old groups for lumbar spine BMD (0.865±0.127 vs 0.672±0.082 and 0.689±0.083, respectively) and in girls at pubertal development stage B3, lumbar spine BMD differed from B5 (0.709±0.073 vs 0.936±0.130) and whole body BMD differed from B4 and B5 (0.867±0.056 vs 0.977±0.086 and 1.040±0.080, respectively). Conclusion: Bone mineralization increased in the B3 breast maturity group, and the critical years for bone mass acquisition were between 13 and 14 years of age for all sites evaluated by densitometry. PMID:21966336

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

    ERIC Educational Resources Information Center

    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…

  15. The influence of pubertal timing and stressful life events on depression and delinquency among Chinese adolescents.

    PubMed

    Chen, Jie; Yu, Jing; Wu, Yun; Zhang, Jianxin

    2015-06-01

    This study aimed to investigate the influences of pubertal timing and stressful life events on Chinese adolescents' depression and delinquency. Sex differences in these influences were also examined. A large sample with 4,228 participants aged 12-15 years (53% girls) was recruited in Beijing, China. Participants' pubertal development, stressful life events, depressive symptoms, and delinquency were measured using self-reported questionnaires. Both early maturing girls and boys displayed more delinquency than their same-sex on-time and late maturing peers. Early maturing girls displayed more depressive symptoms than on-time and late maturing girls, but boys in the three maturation groups showed similar levels of depressive symptoms. The interactive effects between early pubertal timing and stressful life events were significant in predicting depression and delinquency, particularly for girls. Early pubertal maturation is an important risk factor for Chinese adolescents' depression and delinquency. Stressful life events intensified the detrimental effects of early pubertal maturation on adolescents' depression and delinquency, particularly for girls. PMID:26261908

  16. Pubertal growth and epiphyseal fusion

    PubMed Central

    2015-01-01

    The complex networks of nutritional, cellular, paracrine, and endocrine factors are closely related with pubertal growth and epiphyseal fusion. Important influencing factors include chondrocyte differentiation capacity, multiple molecular pathways active in the growth plate, and growth hormone-insulin-like growth factor-I axis activation and epiphyseal fusion through estrogen and its receptors. However, the exact mechanisms of these phenomena are still unclear. A better understanding of the detailed processes involved in the pubertal growth spurt and growth plate closure in longitudinal bone growth will help us develop methods to efficiently promote pubertal growth and delay epiphyseal fusion with fewer adverse effects. PMID:25883921

  17. Current Changes in Pubertal Timing: Revised Vision in Relation with Environmental Factors Including Endocrine Disruptors.

    PubMed

    Parent, Anne-Simone; Franssen, Delphine; Fudvoye, Julie; Pinson, Anneline; Bourguignon, Jean-Pierre

    2016-01-01

    The aim of this chapter is to revise some common views on changes in pubertal timing. This revision is based on recent epidemiological findings on the clinical indicators of pubertal timing and data on environmental factor effects and underlying mechanisms. A current advancement in timing of female puberty is usually emphasized. It appears, however, that timing is also changing in males. Moreover, the changes are towards earliness for initial pubertal stages and towards lateness for final stages in both sexes. Such observations indicate the complexity of environmental influences on pubertal timing. The mechanisms of changes in pubertal timing may involve both the central neuroendocrine control and peripheral effects at tissues targeted by gonadal steroids. While sufficient energy availability is a clue to the mechanism of pubertal development, changes in the control of both energy balance and reproduction may vary under the influence of common determinants such as endocrine-disrupting chemicals (EDCs). These effects can take place right before puberty as well as much earlier, during fetal and neonatal life. Finally, environmental factors can interact with genetic factors in determining changes in pubertal timing. Therefore, the variance in pubertal timing is no longer to be considered under absolutely separate control by environmental and genetic determinants. Some recommendations are provided for evaluation of EDC impact in the management of pubertal disorders and for possible reduction of EDC exposure along the precautionary principle.

  18. Current Changes in Pubertal Timing: Revised Vision in Relation with Environmental Factors Including Endocrine Disruptors.

    PubMed

    Parent, Anne-Simone; Franssen, Delphine; Fudvoye, Julie; Pinson, Anneline; Bourguignon, Jean-Pierre

    2016-01-01

    The aim of this chapter is to revise some common views on changes in pubertal timing. This revision is based on recent epidemiological findings on the clinical indicators of pubertal timing and data on environmental factor effects and underlying mechanisms. A current advancement in timing of female puberty is usually emphasized. It appears, however, that timing is also changing in males. Moreover, the changes are towards earliness for initial pubertal stages and towards lateness for final stages in both sexes. Such observations indicate the complexity of environmental influences on pubertal timing. The mechanisms of changes in pubertal timing may involve both the central neuroendocrine control and peripheral effects at tissues targeted by gonadal steroids. While sufficient energy availability is a clue to the mechanism of pubertal development, changes in the control of both energy balance and reproduction may vary under the influence of common determinants such as endocrine-disrupting chemicals (EDCs). These effects can take place right before puberty as well as much earlier, during fetal and neonatal life. Finally, environmental factors can interact with genetic factors in determining changes in pubertal timing. Therefore, the variance in pubertal timing is no longer to be considered under absolutely separate control by environmental and genetic determinants. Some recommendations are provided for evaluation of EDC impact in the management of pubertal disorders and for possible reduction of EDC exposure along the precautionary principle. PMID:26680578

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

    PubMed Central

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

    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 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. PMID:24548554

  20. Advanced dental maturation in New Zealand Maori and Pacific Island children.

    PubMed

    Moananui, Raymond Te; Kieser, Jules A; Herbison, Peter; Liversidge, Helen M

    2008-01-01

    This study employs Demirjian's (1994: CD Rom. Norwood, MA: Silver Platter Education) method for assessing dental maturation to compare the rates of development in children of three ethnic populations living in New Zealand-Maori, Pacific Island, and European. We test the hypothesis that Maori and Pacific Island children will have significantly advanced dental maturation compared with New Zealand children of European extraction. The study population consists of orthopantomographs of 1,343 children (623 females and 660 males) between the ages of 2.5 and 14 years, and involves three ethnic groups-Maori, European, and Pacific Islander. Bland/Altman plots for the mean chronological age against the age difference suggest that dental age as determined by the Demirjian method is consistently lower than the chronological age of the children examined. A mixed model regression analysis shows that this difference between dental and chronological age is significantly greater in Maori than in European children (regression coefficient = 0.414; z = 7.01; P < 0.001) and also significantly greater in Pacific Island children than European children (regression coefficient = 0.574; z = 6.25; P < 0.001). Regression analysis shows that the 50th quantile maturity score of boys and girls differs by 1.49 (t = -6.18, P < 0.01) and the interaction of sex and age is also significantly different (t = -2.44, P < 0.01). Similarly, Maori girls show a difference in maturity score of 1.28 (t = -3.77, P < 0.01). However, the slopes for Maori boys and girls did not differ significantly (age/sex interaction, t = -1.25, P = 0.212). We conclude that Pacific Island children are advanced in dental maturity compared with Maori children who in turn are more advanced than New Zealand children of European origin. PMID:17929243

  1. Personal-Accentuation and Contextual-Amplification Models of Pubertal Timing: Predicting Youth Depression

    PubMed Central

    Rudolph, Karen D.; Troop-Gordon, Wendy

    2011-01-01

    This research examined personal-accentuation and contextual-amplification models of pubertal timing, wherein personal and contextual risks magnify the effects of earlier pubertal maturation on youth depression. A sample of 167 youth (M age = 12.41 years, SD = 1.19) and their maternal caregivers completed semi-structured interviews and questionnaires at two waves. Consistent with a personal-accentuation model, earlier pubertal maturation more strongly predicted subsequent depression in youth with prior depression, certain personality traits, and maladaptive stress responses than in youth without these personal risks. Several of these effects were specific to earlier-maturing girls. Consistent with a contextual-amplification model, earlier pubertal maturation more strongly predicted subsequent depression in youth exposed to recent maternal depression and family stress than in youth without these contextual risks. These findings identify key characteristics of youth and their family context that help to explain individual variation in depressive reactions to earlier pubertal maturation. More broadly, this research contributes to integrative models of depression that consider the interplay among personal vulnerability, contextual risk, and developmental transitions. PMID:20423552

  2. Detrimental Psychological Outcomes Associated with Early Pubertal Timing in Adolescent Girls

    ERIC Educational Resources Information Center

    Mendle, Jane; Turkheimer, Eric; Emery, Robert E.

    2007-01-01

    Though often discussed as a discrete event, puberty comprises one segment of a larger developmental continuum and is notable for rapid transformation across a multitude of domains. Research suggests that an earlier rate of pubertal maturation in girls correlates with a number of detrimental outcomes compared with on-time or later maturation. The…

  3. Racial disparities in pubertal development.

    PubMed

    Ramnitz, Mary Scott; Lodish, Maya B

    2013-09-01

    The question of whether or not children, particularly girls, are entering puberty earlier than they did in the past has been a concern in both the medical community and the general population. A secular trend analysis of the current data on pubertal timing in boys and girls is limited by variations in the study design, the population assessed, and the methods used to determine pubertal development. These differences present a challenge when interpreting the available data, especially when comparing multiple studies. The influence of race on pubertal timing and development had not been assessed before the 1970s. The purpose of this article is to review the reported variations in pubertal timing among different racial/ethnic groups. Data suggest African American girls enter puberty earlier and reach menarche earlier than Caucasian and Hispanic girls. In addition, the trend toward earlier timing of puberty seems to be occurring faster in African American girls compared with Caucasian girls over the past 25 years. While the mechanism and understanding of the cause of racial disparities in pubertal development remain to be discerned, genetic and/or environmental factors may play a role and require further investigation.

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

    PubMed

    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.

  5. Detrimental Psychological Outcomes Associated with Early Pubertal Timing in Adolescent Girls

    PubMed Central

    Mendle, Jane; Turkheimer, Eric; Emery, Robert E.

    2010-01-01

    Though often discussed as though it were a discrete event, puberty comprises one segment of a larger developmental continuum and is notable for rapid transformation across a multitude of domains. Research suggests that an earlier rate of pubertal maturation in girls correlates with a number of detrimental outcomes compared with on-time or later maturation. The present review synthesizes the research on negative psychological sequelae of early pubertal timing in adolescent girls. Emphasis is on three theoretical perspectives by which precocious development is believed to affect the emergence of adverse outcomes: biological, psychosocial, and selection effects. PMID:20740062

  6. Attenuated hypothalamic-pituitary-adrenal axis functioning predicts accelerated pubertal development in girls 1 year later.

    PubMed

    Saxbe, Darby E; Negriff, Sonya; Susman, Elizabeth J; Trickett, Penelope K

    2015-08-01

    Accelerated pubertal development has been linked to adverse early environments and may heighten subsequent mental and physical health risks. Hypothalamic-pituitary-adrenal axis functioning has been posited as a mechanism whereby stress may affect pubertal development, but the literature lacks prospective tests of this mechanism. The current study assessed 277 youth (M = 10.84 years, SD = 1.14), 138 boys and 139 girls, who reported on their pubertal development and underwent the Trier Social Stress Test for Children at baseline and returned to the laboratory approximately 1 year later (M = 1.12 years, range = 0.59-1.98 years). For girls, lower cortisol area under the curve (with respect to ground) at Time 1 predicted more advanced pubertal development at Time 2, controlling for Time 1 pubertal development. This association persisted after additional covariates including age, body mass index, race, and maltreatment history were introduced, and was driven by adrenal rather than gonadal development. Cortisol was not linked to boys' subsequent pubertal development, and no interaction by gender or by maltreatment appeared. These results suggest that attenuated cortisol, reported in other studies of children exposed to early adversity, may contribute to accelerated pubertal tempo in girls.

  7. The degenerative fate of germ cells not conforming to stage in the pubertal golden hamster testis.

    PubMed

    Miething, A

    1998-11-01

    In the golden hamster (Mesocricetus auratus), pubertal establishment of spermatogenesis includes a defined period (d 26-30 of life) during which elongation of spermatids is selectively arrested. The resulting appearance of germ cell associations not conforming to stage and the phenomenon of desynchronisation-related germ cell degeneration are analysed both quantitatively and qualitatively by means of light and 'retrospective' electron microscopy. From d 26 onwards, the portion of tubules containing non-stage conforming germ cell associations gradually increases up to 37.5% of sectioned tubules on d 32. Concomitantly, the degree of desynchronisation rises to a maturational gap between spermatids and associated younger germ cells of 7 stages of the seminiferous epithelium cycle, i.e. of fully half a cycle. Beyond d 32, the frequency of desynchronised tubule segments decreases again. Some of the arrested round spermatids and, eventually, all belatedly elongating spermatids degenerate and are lost from the epithelium. Thus a regular maturation of advanced spermatids does not succeed under non-stage conforming conditions. Possibly it is not the desynchronisation between the associated germ cell generations and the spermatids by itself that impedes normal further development of the latter cells. Instead this may be due to the maturational delay of the stage-aberrant cells by several stages compared to the seminiferous epithelium as a whole and, especially, in relation to the stage-conditioned functional state of the neighbouring Sertoli cells.

  8. Advanced Mucinous Adenocarcinoma Arising from a Mature Cystic Teratoma: A Case Report and Literature Review

    PubMed Central

    Miyasaka, Aki; Nishikawa, Tadaaki; Kozawa, Eito; Yasuda, Masanori; Fujiwara, Keiichi; Hasegawa, Kosei

    2016-01-01

    Purpose To describe the postoperative progressive course of advanced-stage adenocarcinoma arising from a mature cystic teratoma (MCT) and review the literature regarding this disease. Methods A 59-year-old woman visited our hospital with an abdominal mass. Laparotomy showed enlargement of the left ovary and dissemination throughout the abdominal and pelvic cavities. The diagnosis was FIGO stage IIIB adenocarcinoma arising from a MCT. We report this case in detail with a review of the literature. Results A literature search yielded 9 cases of stage III adenocarcinoma with malignant transformation. Six of these 9 patients died within 12 months after diagnosis. Of the 8 patients who underwent postoperative chemotherapy, 3 survived for over 39 months. The review indicates that prognosis of adenocarcinoma is as poor as that for squamous cell carcinoma arising from a MCT. Conclusions In general, as with this case, prognosis of advanced adenocarcinoma associated with a MCT is poor. However, we should be aware that not all patients are resistant to chemotherapy. PMID:27462234

  9. The Impact of Pubertal Timing and Parental Control on Adolescent Problem Behaviors

    ERIC Educational Resources Information Center

    Arim, Rubab G.; Shapka, Jennifer D.

    2008-01-01

    This study examined the relationship among pubertal timing, parental control, and problem behaviors. There were 267 participants, whose ages ranged from 9 to 16 years. Both maternal and paternal psychological control predicted problem behaviors over and above the effects of behavioral control. For boys, early maturation and high levels of paternal…

  10. Effect of high and low antral follicle count in pubertal beef heifers on IVF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pubertal heifers can be classified between those with high (n = 25) or low (n = 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g. fertility) in an IVF system for high- and low-AFC heifers. From a pool of 120 heifers, 10 high- and 1...

  11. Early Pubertal Timing and the Union Formation Behaviors of Young Women

    ERIC Educational Resources Information Center

    Cavanagh, Shannon E.

    2011-01-01

    This study examined whether the transition into adolescence, proxied by pubertal timing, shaped the transition into adulthood, proxied by union formation behaviors, among contemporary American women. In a sample drawn from Add Health (n = 7,523), early maturing girls reported an accelerated transition to marriage and cohabitation in young…

  12. Relations of Pubertal Timing and Depressive Symptoms to Substance Use in Early Adolescence.

    ERIC Educational Resources Information Center

    Wiesner, Margit; Ittel, Angela

    2002-01-01

    Tested three hypotheses concerning effects of pubertal timing on substance use during early adolescence. Findings supported only the stage termination hypothesis. Early maturing boys and girls reported a higher frequency of substance use within the following year after puberty than did the other participants, with the effects being more pronounced…

  13. The Need for Technology Maturity of Any Advanced Capability to Achieve Better Life Cycle Cost (LCC)

    NASA Technical Reports Server (NTRS)

    Robinson, John W.; Levack, Daniel J. H.; Rhodes, Russel E.; Chen, Timothy T.

    2009-01-01

    Programs such as space transportation systems are developed and deployed only rarely, and they have long development schedules and large development and life cycle costs (LCC). They have not historically had their LCC predicted well and have only had an effort to control the DDT&E phase of the programs. One of the factors driving the predictability, and thus control, of the LCC of a program is the maturity of the technologies incorporated in the program. If the technologies incorporated are less mature (as measured by their Technology Readiness Level - TRL), then the LCC not only increases but the degree of increase is difficult to predict. Consequently, new programs avoid incorporating technologies unless they are quite mature, generally TRL greater than or equal to 7 (system prototype demonstrated in a space environment) to allow better predictability of the DDT&E phase costs unless there is no alternative. On the other hand, technology development programs rarely develop technologies beyond TRL 6 (system/subsystem model or prototype demonstrated in a relevant environment). Currently the lack of development funds beyond TRL 6 and the major funding required for full scale development leave little or no funding available to prototype TRL 6 concepts so that hardware would be in the ready mode for safe, reliable and cost effective incorporation. The net effect is that each new program either incorporates little new technology or has longer development schedules and costs, and higher LCC, than planned. This paper presents methods to ensure that advanced technologies are incorporated into future programs while providing a greater accuracy of predicting their LCC. One method is having a dedicated organization to develop X-series vehicles or separate prototypes carried on other vehicles. The question of whether such an organization should be independent of NASA and/or have an independent funding source is discussed. Other methods are also discussed. How to make the

  14. Changes in primary metabolites and polyphenols in the peel of "Braeburn" apples (Malus domestica Borkh.) during advanced maturation.

    PubMed

    Bizjak, Jan; Mikulic-Petkovsek, Maja; Stampar, Franci; Veberic, Robert

    2013-10-30

    During the two growing seasons the evolution of primary metabolites and wide range of polyphenols in the "Braeburn" apple peel during advanced maturation were investigated. During the five weeks sucrose significantly increased, whereas fructose and glucose fluctuated around the same level in one season and decreased in another. Regarding malic and citric acids, an expected decrease was recorded. The concentrations of hydroxycinnamic acids, dihydrochalcones, and flavanols remained quite constant or slightly decreased during advanced apple ripening. On the contrary an intensive accumulation of quercetin glycosides and anthocyanins took place during this period, starting with the onset of rapid formation approximately 3 weeks before the technological maturity of apples. Total phenolic content was relatively constant or slightly increased. The present results suggest that measures designed to improve the apple color and quality of "Braeburn" apples should be performed approximately 3-4 weeks before the expected technological maturity of apples.

  15. Breastfeeding versus formula-feeding and girls' pubertal development.

    PubMed

    Kale, Aarti; Deardorff, Julianna; Lahiff, Maureen; Laurent, Cecile; Greenspan, Louise C; Hiatt, Robert A; Windham, Gayle; Galvez, Maida P; Biro, Frank M; Pinney, Susan M; Teitelbaum, Susan L; Wolff, Mary S; Barlow, Janice; Mirabedi, Anousheh; Lasater, Molly; Kushi, Lawrence H

    2015-03-01

    To examine the association of breastfeeding or its duration with timing of girls' pubertal onset, and the role of BMI as a mediator in these associations. A population of 1,237 socio-economically and ethnically diverse girls, ages 6-8 years, was recruited across three geographic locations (New York City, Cincinnati, and the San Francisco Bay Area) in a prospective study of predictors of pubertal maturation. Breastfeeding practices were assessed using self-administered questionnaire/interview with the primary caregiver. Girls were seen on at least annual basis to assess breast and pubic hair development. The association of breastfeeding with pubertal timing was estimated using parametric survival analysis while adjusting for body mass index, ethnicity, birth-weight, mother's education, mother's menarcheal age, and family income. Compared to formula fed girls, those who were mixed-fed or predominantly breastfed showed later onset of breast development [hazard ratios 0.90 (95 % CI 0.75, 1.09) and 0.74 (95 % CI 0.59, 0.94), respectively]. Duration of breastfeeding was also directly associated with age at onset of breast development (p trend = 0.008). Associations between breastfeeding and pubic hair onset were not significant. In stratified analysis, the association of breastfeeding and later breast onset was seen in Cincinnati girls only. The association between breast feeding and pubertal onset varied by study site. More research is needed about the environments within which breastfeeding takes place in order to better understand whether infant feeding practices are a potentially modifiable risk factor that may influence age at onset of breast development and subsequent risk for disease in adulthood.

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

    PubMed

    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.

  17. Psychopathology and Social Competence during the Transition to Adolescence: The Role of Family Adversity and Pubertal Development

    PubMed Central

    Obradović, Jelena; Hipwell, Alison

    2010-01-01

    This study examined developmental processes linking competence and psychopathology in an urban sample of girls during their transition to adolescence. Longitudinal associations among indices of externalizing symptoms, social competence, and internalizing symptoms were also tested within contexts of family adversity and girls' pubertal status. Child, parent, and teacher report were employed to assess core constructs across six annual assessment waves, starting at age 9. Results revealed the significant effect of prior levels of externalizing symptoms on changes in social competence and internalizing symptoms, as well as reciprocal relations between social competence and internalizing symptoms. In addition, girl's maladaptive functioning predicted increases in family adversity exposure over time. Lastly, more mature pubertal status in early assessment waves was linked to an increase in internalizing symptoms; however, this association was reversed by the last assessment, when most girls had reached advance stages of puberty. The timing of these effects reveals important targets for future interventions aimed at promoting the successful adaptation of girls in adolescence. PMID:20576183

  18. Intra-pituitary relationship of follicle stimulating hormone and luteinizing hormone during pubertal development in Atlantic bluefin tuna (Thunnus thynnus).

    PubMed

    Berkovich, Nadia; Corriero, Aldo; Santamaria, Nicoletta; Mylonas, Constantinos C; Vassallo-Aguis, Robert; de la Gándara, Fernando; Meiri-Ashkenazi, Iris; Zlatnikov, Vered; Gordin, Hillel; Bridges, Christopher R; Rosenfeld, Hanna

    2013-12-01

    As part of the endeavor aiming at the domestication of Atlantic bluefin tuna (BFT; Thunnus thynnus), first sexual maturity in captivity was studied by documenting its occurrence and by characterizing the key hormones of the reproductive axis: follicle stimulating hormone (FSH) and luteinizing hormone (LH). The full length sequence encoding for the related hormone β-subunits, bftFSHβ and bftLHβ, were determined, revealing two bftFSHβ mRNA variants, differing in their 5' untranslated region. A quantitative immuno-dot-blot assay to measure pituitary FSH content in BFT was developed and validated enabling, for the first time in this species, data sets for both LH and FSH to be compared. The expression and accumulation patterns of LH in the pituitary showed a steady increase of this hormone, concomitant with fish age, reaching higher levels in adult females compared to males of the same age class. Conversely, the pituitary FSH levels were elevated only in 2Y and adult fish. The pituitary FSH to LH ratio was consistently higher (>1) in immature than in maturing or pubertal fish, resembling the situation in mammals. Nevertheless, the results suggest that a rise in the LH storage level above a minimum threshold may be an indicator of the onset of puberty in BFT females. The higher pituitary LH levels in adult females over males may further support this notion. In contrast three year-old (3Y) males were pubertal while cognate females were still immature. However, it is not yet clear whether the advanced puberty in the 3Y males was a general feature typifying wild BFT populations or was induced by the culture conditions. Future studies testing the effects of captivity and hormonal treatments on precocious maturity may allow for improved handling of this species in a controlled environment which would lead to more cost-efficient farming.

  19. Timing and tempo: Exploring the complex association between pubertal development and depression in African American and European American girls

    PubMed Central

    Keenan, Kate; Culbert, Kristen; Grimm, Kevin J.; Hipwell, Alison; Stepp, Stephanie

    2014-01-01

    The relative contribution of pubertal timing and tempo to the development of depression has not been tested in a large, representative sample, nor has the interface among pubertal maturation, depression, and race. Participants were a community-based sample of 2,450 girls from the Pittsburgh Girls Study (PGS) who were interviewed annually from ages 9 to 17 years. Pubertal timing and tempo were characterized as a unitary construct and also separately for pubic hair and breast development using child and maternal report. Depression symptoms were assessed annually. African-American females had higher depression symptoms and progressed through puberty earlier, but at a slower tempo than European American girls. Girls with earlier timing had higher levels of depression symptoms at age 10 years. Slower tempo was associated with higher depression symptoms at age 10, and faster tempo was associated with increases in depression from ages 10 to 13. As well, race moderated the associations among timing, tempo, and depression symptoms, and the association between race and depression was partially mediated by pubertal timing and tempo. Pubertal timing and tempo and race contribute to the developmental course of depression from early to late adolescence. The pattern of association varies as a function of the developmental window within which depression is assessed. Thus, repeated measures of depression symptoms and puberty across the span of pubertal development are necessary for exploring the relative importance of dimensions of pubertal development to depression etiology. PMID:25314262

  20. Timing and tempo: Exploring the complex association between pubertal development and depression in African American and European American girls.

    PubMed

    Keenan, Kate; Culbert, Kristen M; Grimm, Kevin J; Hipwell, Alison E; Stepp, Stephanie D

    2014-11-01

    The relative contribution of pubertal timing and tempo to the development of depression has not been tested in a large, representative sample, nor has the interface among pubertal maturation, depression, and race been tested. Participants were a community-based sample of 2,450 girls from the Pittsburgh Girls Study who were interviewed annually from ages 9 to 17 years. Pubertal timing and tempo were characterized as a unitary construct and also separately for pubic hair and breast development using child and maternal report. Depression symptoms were assessed annually. African American girls had higher depression symptoms and progressed through puberty earlier, but at a slower tempo than European American girls. Girls with earlier timing had higher levels of depression symptoms at age 10 years. Slower tempo was associated with higher depression symptoms at age 10, and faster tempo was associated with increases in depression from ages 10 to 13. As well, race moderated the associations among timing, tempo, and depression symptoms, and the association between race and depression was partially mediated by pubertal timing and tempo. Pubertal timing and tempo and race contribute to the developmental course of depression from early to late adolescence. The pattern of association varies as a function of the developmental window within which depression is assessed. Thus, repeated measures of depression symptoms and puberty across the span of pubertal development are necessary for exploring the relative importance of dimensions of pubertal development to depression etiology.

  1. Problems in Studying and Defining Pubertal Events.

    ERIC Educational Resources Information Center

    Brooks-Gunn, Jeanne; Petersen, Anne C.

    1984-01-01

    Issues in studying pubertal events are examined, including whether puberty is best characterized as a social construction or a physical event, whether early adolescence is a transitional or distinct life period, life events associated with puberty, boundaries of early adolescence, and possible models for studying pubertal change. (Author/BW)

  2. Association Between Urinary Phthalates and Pubertal Timing in Chinese Adolescents

    PubMed Central

    Shi, Huijing; Cao, Yang; Shen, Qing; Zhao, Yan; Zhang, Zhe; Zhang, Yunhui

    2015-01-01

    Background Phthalates are synthetic chemicals and ubiquitous environmental contaminants, with hormonal activity that may alter the course of pubertal development in children. Objectives To determine whether exposure to phthalate metabolites is associated with timing of pubertal development in a cross-sectional study of a school-based clustered sample of 503 children from a suburban district in Shanghai, China, who were 7–14 years of age at enrollment (2010 October to November). Methods We analyzed six phthalate metabolites in urine samples by isotope-dilution liquid chromatography tandem mass spectrometry. The associations of exposures to phthalates with pubertal timing of testes, breast, and pubic hair development (represented as Tanner stages) were evaluated using an ordered logistic regression model adjusted for chronological age, body fat proportion (BF%), and parental education. Results In boys, urinary mono-n-butyl phthalate (MBP) levels were negatively associated with testicular volume, and mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) levels were negatively associated with pubic hair stages. The odds of being in an advanced stage were decreased by 43%–51%. In girls, mono (2-ethylhexyl) phthalate (MEHP), MEHHP, and MEOHP levels, as well as the sum of these levels, were positively associated with breast stages, and the association was much stronger in girls with high BF%; the odds of being in an advanced stage were increase by 29% to 50%. Conclusions Phthalate metabolites investigated in this study show significant associations with pubertal timing both in boys and in girls, especially among girls with high BF%. PMID:26212725

  3. Environmental factors influencing growth and pubertal development.

    PubMed Central

    Delemarre-van de Waal, H A

    1993-01-01

    Postnatal growth is based on hereditary signals and environmental factors in a complex regulatory network. Each factor must be in an optimal state for normal growth of the child. Fetal conditions may also have consequences on postnatal height. Intrauterine growth retardation can be recovered postnatally, although postnatal growth remains depressed in about one-third of cases. After birth, the environment may exert either a positive or negative effect on growth. In underdeveloped countries, malnutrition plays a major role in inhibiting the growth process. Children from families of higher socioeconomic classes are taller than their coevals in the lower socioeconomic groups. Urbanization also has a positive effect on growth. Better child care is supported by sufficient food supply, appropriate health and sanitation services, and a higher level of education. Over the last century, these factors have induced a taller stature and a more rapid maturity in Europe, North America, and Australia; a phenomenon which has been referred to as "the secular trend" in growth. Recently, a secular trend has also been reported in some developing countries. Although urbanization in general appears to be associated with better conditions of living, this is not the case in the slums of South America or in Africa where rural children are better off than children living in the poor cities. This paper describes in more detail the different hereditary and environmental factors that act during the fetal period and postnatally, and which play a role in human growth and pubertal development. PMID:8243404

  4. Pubertal Status Predicts Back Pain, Overtiredness, and Dizziness in American and Dutch Adolescents

    PubMed Central

    Rosmalen, Judith G. M.; Ormel, Johan; Verhulst, Frank C.; Hunfeld, Joke A. M.; Mancl, Lloyd A.; Oldehinkel, Albertine J.; LeResche, Linda

    2011-01-01

    OBJECTIVE: Functional somatic symptoms, symptoms for which no organic pathologic basis can be found, are more prevalent in girls than in boys, and this difference tends to increase during adolescence. This might be explained, at least in part, by pubertal development. We hypothesized that pubertal maturation predicts the development of most functional somatic symptoms and that this especially is true for girls. METHOD: We used 2 longitudinal population-based studies to examine our hypotheses: the Longitudinal Study of Pain in Adolescents in Seattle (n = 1996 [49.7% girls]) and the Dutch Tracking Adolescents' Individual Lives Survey (n = 2230 [51.0% girls]). Two assessment waves of each study were used. American adolescents were younger than Dutch adolescents at the first (11.6 vs 13.6) and second (14.5 vs 16.2) assessment waves, but they were in about the same pubertal development stage. Functional somatic symptoms were measured by pain questions, the Symptom Checklist-90, and the Youth Self-report. The Pubertal Development Scale was used to assess pubertal development on a continuous scale in both cohorts. RESULTS: Ordinal logistic regression analyses revealed that American and Dutch adolescents at a later pubertal status at baseline were more likely (odds ratios ranged from 1.24 to 1.61) to report back pain, overtiredness, and dizziness but not stomach pain and headache 2 to 3 years later. Although these relationships were not equally strong for boys and girls, no significant gender differences were found. CONCLUSIONS: Pubertal status predicted the frequency of some, but not all, functional somatic symptoms at follow-up. PMID:21807699

  5. Sex steroids and brain structure in pubertal boys and girls.

    PubMed

    Peper, Jiska S; Brouwer, Rachel M; Schnack, Hugo G; van Baal, G Caroline; van Leeuwen, Marieke; van den Berg, Stéphanie M; Delemarre-Van de Waal, Henriëtte A; Boomsma, Dorret I; Kahn, René S; Hulshoff Pol, Hilleke E

    2009-04-01

    Sex steroids exert important organizational effects on brain structure. Early in life, they are involved in brain sexual differentiation. During puberty, sex steroid levels increase considerably. However, to which extent sex steroid production is involved in structural brain development during human puberty remains unknown. The relationship between pubertal rises in testosterone and estradiol levels and brain structure was assessed in 37 boys and 41 girls (10-15 years). Global brain volumes were measured using volumetric-MRI. Regional gray and white matter were quantified with voxel-based morphometry (VBM), a technique which measures relative concentrations ('density') of gray and white matter after individual global differences in size and shape of brains have been removed. Results showed that, corrected for age, global gray matter volume was negatively associated with estradiol levels in girls, and positively with testosterone levels in boys. Regionally, a higher estradiol level in girls was associated with decreases within prefrontal, parietal and middle temporal areas (corrected for age), and with increases in middle frontal-, inferior temporal- and middle occipital gyri. In boys, estradiol and testosterone levels were not related to regional brain structures, nor were testosterone levels in girls. Pubertal sex steroid levels could not explain regional sex differences in regional gray matter density. Boys were significantly younger than girls, which may explain part of the results. In conclusion, in girls, with the progression of puberty, gray matter development is at least in part directly associated with increased levels of estradiol, whereas in boys, who are in a less advanced pubertal stage, such steroid-related development could not (yet) be found. We suggest that in pubertal girls, estradiol may be implicated in neuronal changes in the cerebral cortex during this important period of brain development.

  6. Regulation and disorders of pubertal timing.

    PubMed

    Nathan, Brandon M; Palmert, Mark R

    2005-09-01

    Disorders of pubertal timing are common and challenging problems for pediatric endocrinologists. Early or late puberty can have immediate effects on a child's psychosocial well-being and may have long-term effects on adult stature. Much is known about the regulation of the hypothalamic-pituitary-gonadal axis, but the triggers of pubertal onset in the general population remain elusive. This article reviews recent data suggesting a possible shift in the age of pubertal onset; current knowledge regarding factors that regulate the onset of puberty; and the etiologies, diagnosis, and treatment of precocious and delayed puberty.

  7. Elucidating the mechanisms linking early pubertal timing, sexual activity, and substance use for maltreated versus nonmaltreated adolescents

    PubMed Central

    Negriff, Sonya; Brensilver, Matthew; Trickett, Penelope K.

    2015-01-01

    Purpose To test models linking pubertal timing, peer substance use, sexual behavior, and substance use for maltreated versus comparison adolescents. Three theoretical mechanisms were tested: 1) peer influence links early pubertal timing to later sexual behavior and substance use, 2) early maturers engage in substance use on their own and then select substance-using friends, or 3) early maturers initiate sexual behaviors which leads them to substance-using peers. Methods The data came from a longitudinal study of the effects of child maltreatment on adolescent development (303 maltreated and 151 comparison adolescents; age: 9–13 years at initial wave). Multiple-group structural equation models tested the hypotheses across three timepoints including variables of pubertal timing, perception of peer substance use, sexual behavior, and self-reported substance use. Results Early pubertal timing was associated with substance-using peers only for maltreated adolescents, indicating the mediation path from early pubertal timing through substance-using peers to subsequent adolescent substance use and sexual behavior only holds for maltreated adolescents. Mediation via sexual behavior was significant for both maltreated and comparison adolescents. This indicates that sexual behavior may be a more universal mechanism linking early maturation with risky friends regardless of adverse life experiences. Conclusions The findings are a step toward elucidating the developmental pathways from early puberty to risk behavior and identifying early experiences that may alter mediation effects. PMID:26003577

  8. Male pubertal development: are endocrine-disrupting compounds shifting the norms?

    PubMed

    Zawatski, William; Lee, Mary M

    2013-01-01

    Endocrine-disrupting compounds (EDCs) are synthetic or natural compounds that interfere with endogenous endocrine action. The frequent use of chemicals with endocrine active properties in household products and contamination of soil, water, and food sources by persistent chemical pollutants result in ubiquitous exposures. Wildlife observations and animal toxicological studies reveal adverse effects of EDCs on reproductive health. In humans, a growing number of epidemiological studies report an association with altered pubertal timing and progression. While these data are primarily reported in females, this review will focus on the small number of studies performed in males that report an association of polychlorinated biphenyls with earlier sexual maturity rating and confirm subtle effects of lead, dioxins, and endosulfan on delaying pubertal onset and progression in boys. Recent studies have also demonstrated that EDC exposure may affect pubertal testosterone production without having a noticeable effect on sexual maturity rating. A limitation to understand the effects of EDCs in humans is the potential for confounding due to the long temporal lag from early-life exposures to adult outcomes. The complex interplay of multiple environmental exposures over time also complicates the interpretation of human studies. These studies have identified critical windows of vulnerability during development when exposures to EDCs alter critical pathways and affect postnatal reproductive health. Contemporaneous exposures can also disrupt the hypothalamic-pituitary-gonadal axis. This paper will review the normal process of puberty in males and summarize human data that suggest potential perturbations in pubertal onset and tempo with early-life exposures to EDCs.

  9. Adipocytokine and ghrelin responses to acute exercise and sport training in children during growth and maturation.

    PubMed

    Jürimäe, Jaak

    2014-11-01

    Physical exercise is known to regulate energy balance. Important to this regulatory system is the existence of several peptides that communicate the status of body energy stores to the brain and are related to the body fatness including leptin, adiponectin and ghrelin. These hormones assist in regulating energy balance as well as somatic and pubertal growth in children. It appears that rather few studies have investigated the responses of leptin, adiponectin and ghrelin to acute exercise and these studies have demonstrated no changes in these peptides as a result of exercise. Leptin levels are decreased and may remain unchanged advancing from prepuberty to pubertal maturation in young male and female athletes. A limited number of studies indicate that adiponectin levels are not different between prepubertal and pubertal athletes and untrained controls. However, in certain circumstances circulating adiponectin could be increased in young athletes after onset of puberty as a result of heavily increased energy expenditure. Ghrelin levels are elevated in young sportsmen. However, pubertal onset decreases ghrelin levels in boys and girls even in the presence of chronically elevated energy expenditure as seen in young athletes. Ghrelin may also be used as an indicator of energy imbalance across the menstrual cycle in adolescent athletes. There are no studies with high-molecular-weight adiponectin and only very few studies with acylated ghrelin responses to acute exercise and chronic training have been performed in young athletes. Since these forms of adiponectin and ghrelin have been thought to be bioactive forms, further studies with these specific forms of adiponectin and ghrelin are needed. In conclusion, further studies should be conducted to investigate the response of these hormones to acute and chronic negative energy balance to better understand their role in regulating energy balance during growth and maturation in young athletes.

  10. Pubertal Stage and Brain Anatomy in Girls

    PubMed Central

    Blanton, Rebecca E.; Cooney, Rebecca E.; Joormann, Jutta; Eugène, Fanny; Glover, Gary H.; Gotlib, Ian H.

    2015-01-01

    Studies of puberty have focused primarily on changes in hormones and on observable physical bodily characteristics. Little is known, however, about the nature of the relation between pubertal status and brain physiology. This is particularly important given findings that have linked the onset of puberty with both changes in cognitive functioning and increases in the incidence of depression and anxiety. The present study examined relations between pubertal stage, as assessed by Tanner Staging, and brain anatomy in a sample of 54 girls aged 9 - 15 years. Brain morphometric analysis was conducted using high-resolution magnetic resonance imaging (MRI). The hippocampus and amygdala were manually traced on MRI scans in all participants. Stepwise regression analyses were conducted with total intracranial volume (ICV), age, and pubertal status as the predictor variables and hippocampus and amygdala volumes as outcome variables. Pubertal status was significantly associated with left amygdala volume, after controlling for both age and intracranial volume (ICV). In addition, puberty was related to right hippocampus and amygdala volumes, after controlling for ICV. In contrast, no significant associations were found between age and hippocampal and amygdala volumes after controlling for pubertal status and ICV. These findings highlight the importance of the relation between pubertal status and morphometry of the hippocampus and amygdala, and of limbic and subcortical structures that have been implicated in emotional and social behavior. PMID:22569152

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

    ERIC Educational Resources Information Center

    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…

  12. T Lymphocyte Maturation Is Impaired in Healthy Young Individuals Carrying Trisomy 21 (Down Syndrome)

    ERIC Educational Resources Information Center

    Guazzarotti, Laura; Trabattoni, Daria; Castelletti, Eleonora; Boldrighini, Benedetta; Piacentini, Luca; Duca, Piergiorgio; Beretta, Silvia; Pacei, Michela; Caprio, Cristiana; Vigano, Alessandra; di Natale, Berardo; Zuccotti, Gian Vincenzo; Clerici, Mario

    2009-01-01

    Cytokine production, immune activation, T lymphocytes maturation, and serum IL-7 concentration were examined in 24 youngsters with Down syndrome and no acquired diseases (healthy Down syndrome [12 prepubertal, 13 pubertal]) and 42 age- and gender-matched controls (20 prepubertal, 22 pubertal). Results showed that a complex immune and impairment is…

  13. Associations Among Pubertal Development, Empathic Ability, and Neural Responses While Witnessing Peer Rejection in Adolescence

    PubMed Central

    Masten, Carrie L.; Eisenberger, Naomi I.; Pfeifer, Jennifer H.; Colich, Natalie L.; Dapretto, Mirella

    2012-01-01

    Links among concurrent and longitudinal changes in pubertal development and empathic ability from age 10 to 13 and neural responses while witnessing peer rejection at age 13 were examined in 16 participants. More advanced pubertal development at age 13, and greater longitudinal increases in pubertal development, related to increased activity in regions underlying cognitive aspects of empathy. Likewise, at age 13 greater perspective taking related to activity in cognitive empathy-related regions; however, affective components of empathy (empathic concern and personal distress) were additionally associated with activity in affective pain-related regions. Longitudinal increases in empathic ability related to cognitive and affective empathy-related circuitry. Findings provide preliminary evidence that physical and cognitive-emotional development relate to adolescents’ neural responses when witnessing peer rejection. PMID:23379360

  14. Do Trajectories of Household Risk in Childhood Moderate Pubertal Timing Effects on Substance Initiation in Middle School?

    ERIC Educational Resources Information Center

    Lynne-Landsman, Sarah D.; Graber, Julia A.; Andrews, Judy A.

    2010-01-01

    Previous research on pubertal timing has either evaluated contextual predictors of early puberty or negative adjustment outcomes associated with off-time development, especially early maturation. In this study, we integrated these 2 lines of research by evaluating the moderating influence of early childhood household risk on associations between…

  15. The Effects of Pubertal Changes on Body Image and Relations with Peers of the Opposite Sex in Adolescence.

    ERIC Educational Resources Information Center

    Rodriguez-Tome, H.; And Others

    1993-01-01

    Examined impact of pubertal maturation on body image and on perceived quality of relations with opposite sex peers in adolescence. Findings from 157 French adolescents aged 11 to 16 years confirmed that boys evaluated themselves on attractiveness more positively than girls. Found no sex difference on perceived physical condition. (Author/NB)

  16. Effect of high and low antral follicle count in pubertal beef heifers on in vitro fertilization (IVF)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pubertal heifers can be classified between those with high (= 25) and low (= 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g., fertility) in an in vitro fertilization (IVF) system for high and low AFC heifers. From a pool of 120...

  17. In vitro fertilization (IVF) from low or high antral follicle count pubertal beef heifers using semi-defined culture conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antral follicle counts (AFC) vary among pubertal beef heifers. Our objective was to compare the in vitro maturation and fertilization of oocytes collected from low and high AFC heifers. Previously we reported results using serum-based IVF media and in this study report results using semi-defined m...

  18. The Effects of Gender and Maturational Status on Generalized Joint Laxity in Young Athletes

    PubMed Central

    Quatman, Carmen E.; Ford, Kevin R.; Myer, Gregory D.; Paterno, Mark V.; Hewett, Timothy E.

    2008-01-01

    Our purpose was to examine the effects of pubertal status on generalized joint laxity in a population of male and female athletes. We hypothesized that females would show higher generalized joint laxity after the onset of puberty while males would not. This cross-sectional cohort study included 275 female and 143 male middle school and high school basketball and soccer athletes. Joint laxity was assessed using the Beighton and Horan Joint Mobility Index. BHJMI scores were averaged and female and male athletes were compared by pubertal stage. Females demonstrated increased joint laxity scores between pre-pubertal and post-pubertal groups (P=0.042), while males did not. Pre-pubertal male and female athletes were not different in cumulative joint laxity scores (female pre-puberty Mean=2.00; male pre-pubertal Mean=1.66). However, following the onset of puberty females (pubertal Mean=2.96; post-pubertal Mean= 3.03) demonstrated a greater joint laxity score compared to males (pubertal Mean=1.24; post-pubertal Mean=1.30). Gender differences in BHJMI score was found at puberty and post-puberty (P<0.001). In contrast to males, females may have greater generalized joint laxity following the onset of puberty. Structural and physiological changes that occur during puberty such as alterations in passive joint restraints, may affect the type, severity and incidence of injuries in the maturing adolescent population. PMID:17597005

  19. Effects of Prenatal Cocaine Exposure on Pubertal Development

    PubMed Central

    Bennett, David S.; Birnkrant, Jennifer M.; Carmody, Dennis P.; Lewis, Michael

    2014-01-01

    The purpose of the current study was to examine the relationship between prenatal cocaine exposure (PCE) and pubertal development. Children (n=192; 41% with PCE) completed the Pubertal Development Scale (Petersen, et al. 1988) and provided salivary dehydroepiandrosterone (DHEA) samples at 6 month intervals from 11 to 13 years. PCE was examined as a predictor of pubertal status, pubertal tempo, and DHEA levels in mixed models analyses controlling for age, sex, environmental risk, neonatal medical problems, other prenatal exposures, and BMI. PCE interacted with age such that PCE predicted slower pubertal tempo during early adolescence. PCE also interacted with age to predict slower increases in DHEA levels during early adolescence. These findings suggest that PCE may affect pubertal development and, if slower pubertal tempo continues, could lead to delayed pubertal status in mid-adolescence. PMID:25446013

  20. Elevated Social Anxiety among Early Maturing Girls

    ERIC Educational Resources Information Center

    Blumenthal, Heidemarie; Leen-Feldner, Ellen W.; Babson, Kimberly A.; Gahr, Jessica L.; Trainor, Casey D.; Frala, Jamie L.

    2011-01-01

    Adolescence is a key period in terms of the development of anxiety psychopathology. An emerging literature suggests that early pubertal maturation is associated with enhanced vulnerability for anxiety symptomatology, although few studies have examined this association with regard to social anxiety. Accordingly, the current study was designed to…

  1. The Stability of Perceived Pubertal Timing across Adolescence

    ERIC Educational Resources Information Center

    Cance, Jessica Duncan; Ennett, Susan T.; Morgan-Lopez, Antonio A.; Foshee, Vangie A.

    2012-01-01

    It is unknown whether perceived pubertal timing changes as puberty progresses or whether it is an important component of adolescent identity formation that is fixed early in pubertal development. The purpose of this study is to examine the stability of perceived pubertal timing among a school-based sample of rural adolescents aged 11-17 (N =…

  2. Relationship between urinary and serum growth hormone and pubertal status.

    PubMed Central

    Crowne, E C; Wallace, W H; Shalet, S M; Addison, G M; Price, D A

    1992-01-01

    Urinary growth hormone (uGH) excretion and serum growth hormone concentrations have been compared in three groups of children. Group 1 consisted of 21 children who had had cranial irradiation as part of their treatment for acute lymphoblastic leukaemia; group 2, 18 normal children; and group 3, 12 boys with constitutional delay in growth and puberty who were in early puberty. Children in groups 1 and 2 each had a 24 hour serum growth hormone profile (sampling every 20 minutes) and concurrent urine collection. The 12 boys in group 3 had a total of 21 profiles (sampling every 15 minutes for 12 hours) and concurrent urine collections. In the prepubertal children (n = 17), in both groups 1 and 2, there was a significant correlation between mean serum growth hormone and total uGHng/g creatinine. There were also significant correlations between total uGHng/g creatinine and both peak serum growth hormone and mean amplitude of the pulses in the growth hormone profile. In the pubertal children (n = 22), in groups 1 and 2, whether combined or in separate groups, there was no significant correlation between total uGHng/g creatinine and mean serum growth hormone, peak serum growth hormone, or mean amplitude of the pulses in the growth hormone profile. In group 3 there were significant correlations between total uGHng/g creatinine and both the mean serum growth hormone and mean amplitude of the pulses in the profile. Therefore uGH estimations appear to correlate well with serum growth hormone profiles in children who are prepubertal or in early puberty, but not in those further advanced in pubertal development. These results may reflect a variation in the renal handling of growth hormone during pubertal development. uGH estimation may be an unreliable screening investigation for growth hormone sufficiency in mid to late puberty. PMID:1739346

  3. The interactive role of anxiety sensitivity and pubertal status in predicting anxious responding to bodily sensations among adolescents.

    PubMed

    Leen-Feldner, Ellen W; Reardon, Laura E; McKee, Laura G; Feldner, Matthew T; Babson, Kimberly A; Zvolensky, Michael J J

    2006-12-01

    The present study examined the interaction between pubertal status and anxiety sensitivity (AS) in predicting anxious and fearful responding to a three-minute voluntary hyperventilation challenge among 124 (57 females) adolescents between the ages of 12 and 17 years (Mage = 15.04; SD = 1.49). As predicted, after controlling for baseline anxiety, age, and gender, there was a significant interaction between pubertal status and AS in predicting anxious responding to bodily sensations to the hyperventilation challenge. Specifically, adolescents reporting more advanced pubertal status and higher levels of AS reported the greatest post-challenge self-reported anxiety focused on bodily sensations, whereas pubertal status had relatively less of an effect on low AS adolescents. A test of specificity also was conducted; as expected, the interaction between AS and pubertal status was unrelated to generalized negative affectivity, suggesting the predictor variables interact to confer specific risk for anxious responding to bodily sensations. Finally, exploratory analyses of psychophysiological reactivity to the challenge indicated AS, but not pubertal status, moderated the relation between challenge-related change in heart-rate and post-challenge anxiety such that high AS youth who had experienced a relatively greater heart-rate change reported the most anxious reactivity to the challenge. Results are discussed in relation to theory regarding vulnerability to anxious responding to bodily sensations among adolescents. PMID:17115272

  4. The interactive role of anxiety sensitivity and pubertal status in predicting anxious responding to bodily sensations among adolescents.

    PubMed

    Leen-Feldner, Ellen W; Reardon, Laura E; McKee, Laura G; Feldner, Matthew T; Babson, Kimberly A; Zvolensky, Michael J J

    2006-12-01

    The present study examined the interaction between pubertal status and anxiety sensitivity (AS) in predicting anxious and fearful responding to a three-minute voluntary hyperventilation challenge among 124 (57 females) adolescents between the ages of 12 and 17 years (Mage = 15.04; SD = 1.49). As predicted, after controlling for baseline anxiety, age, and gender, there was a significant interaction between pubertal status and AS in predicting anxious responding to bodily sensations to the hyperventilation challenge. Specifically, adolescents reporting more advanced pubertal status and higher levels of AS reported the greatest post-challenge self-reported anxiety focused on bodily sensations, whereas pubertal status had relatively less of an effect on low AS adolescents. A test of specificity also was conducted; as expected, the interaction between AS and pubertal status was unrelated to generalized negative affectivity, suggesting the predictor variables interact to confer specific risk for anxious responding to bodily sensations. Finally, exploratory analyses of psychophysiological reactivity to the challenge indicated AS, but not pubertal status, moderated the relation between challenge-related change in heart-rate and post-challenge anxiety such that high AS youth who had experienced a relatively greater heart-rate change reported the most anxious reactivity to the challenge. Results are discussed in relation to theory regarding vulnerability to anxious responding to bodily sensations among adolescents.

  5. Sertoli Cell Differentiation in Pubertal Boars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Meishan boars experience puberty at a younger age than crossbred (BX) boars in association with earlier cessation of Sertoli cell proliferation and smaller post pubertal testicular size. The current study defined changes in expression, assessed by immunohistochemistry, of anti-Mullerian hormone (AMH...

  6. Pubertal Development and Physical Victimization in Adolescence

    ERIC Educational Resources Information Center

    Haynie, Dana L.; Piquero, Alex R.

    2006-01-01

    Although much research has established a link between pubertal development and adolescent involvement in offending, drug use, and other adverse outcomes, no research has examined whether puberty is associated with experiences of violent physical victimization. This is an unfortunate oversight because researchers are only beginning to understand…

  7. Child maltreatment and household dysfunction: associations with pubertal development in a British birth cohort

    PubMed Central

    Li, Leah; Denholm, Rachel; Power, Chris

    2014-01-01

    Background: We aimed to establish the association between adverse childhood experiences (maltreatment and household dysfunction) and pubertal maturation, which is associated with later health outcome(s). Methods: The 1958 British birth cohort (n = 17 638) includes all born in one week, March 1958, followed up to mid adulthood. Pubertal stage was rated by medical personnel at 11 and 16 years of age (y). Childhood maltreatment (neglect or abuse) and household dysfunction scores were constructed from information ascertained in childhood and at 45 y. Results: Childhood neglect, assessed at 7 y, was associated with late pubertal development on several markers after adjusting for early life circumstances: relative risk ratio (RRRadjusted) was 1.13 (95% CI: 1.06,1.21) and 1.06 (1.00,1.12) for late menarche and breast development (females) per unit increase in neglect score ranging 0–7, respectively; 1.14 (1.08,1.20) for late voice change and 1.07 (1.02,1.13) for pubic hair growth (males). The RRRadjusted for late pubic hair (females) and genitalia and facial hair (males) development was 1.04 (P = 0.052 to 0.085). Abuse score (0–3, for physical, sexual or psychological abuse) was associated in females with late menarche [RRRadjusted = 1.17 (1.01,1.36)] and in males with late pubic hair growth [RRRadjusted = 1.16 (1.01,1.34)] per unit increase, but not with other pubertal markers. Neither score (neglect or abuse) was associated with early puberty, but sexual abuse was associated with early [RRRadjusted = 1.86 (1.06,3.29)] as well as late menarche [RRRadjusted = 1.66 (1.02,2.71)] and witnessing abuse with early genitalia development [RRRadjusted = 1.57 (1.02,2.41)]. Household dysfunction score was not associated consistently with pubertal markers. Conclusions: Cumulative neglect by 7 y was associated with delayed development of several pubertal markers. The underlying role of pubertal development in linking childhood neglect with future adult health warrants further

  8. Pubertal alterations in growth and body composition. V. Energy expenditure, adiposity, and fat distribution.

    PubMed

    Roemmich, J N; Clark, P A; Walter, K; Patrie, J; Weltman, A; Rogol, A D

    2000-12-01

    We determined whether activity energy expenditure (AEE, from doubly labeled water and indirect calorimetry) or physical activity [7-day physical activity recall (PAR)] was more related to adiposity and the validity of PAR estimated total energy expenditure (TEE(PAR)) in prepubertal and pubertal boys (n = 14 and 15) and girls (n = 13 and 18). AEE, but not physical activity hours, was inversely related to fat mass (FM) after accounting for the fat-free mass, maturation, and age (partial r = -0.35, P < or = 0.01). From forward stepwise regression, pubertal maturation, AEE, and gender predicted FM (r(2) = 0.36). Abdominal visceral fat and subcutaneous fat were not related to AEE or activity hours after partial correlation with FM, maturation, and age. When assuming one metabolic equivalent (MET) equals 1 kcal. kg body wt(-1). h(-1), TEE(PAR) underestimated TEE from doubly labeled water (TEE bias) by 555 kcal/day +/- 2 SD limits of agreement of 913 kcal/day. The measured basal metabolic rate (BMR) was >1 kcal. kg body wt(-1). h(-1) and remained so until 16 yr of age. TEE bias was reduced when setting 1 MET equal to the measured (bias = 60 +/- 51 kcal/day) or predicted (bias = 53 +/- 50 kcal/day) BMR but was not consistent for an individual child (+/- 2 SD limits of agreement of 784 and 764 kcal/day, respectively) or across all maturation groups. After BMR was corrected, TEE bias remained greatest in the prepubertal girls. In conclusion, in children and adolescents, FM is more strongly related to AEE than activity time, and AEE, pubertal maturation, and gender explain 36% of the variance in FM. PAR should not be used to determine TEE of individual children and adolescents in a research setting but may have utility in large population-based pediatric studies, if an appropriate MET value is used to convert physical activity data to TEE data.

  9. Pubertal Onset in Girls is Strongly Influenced by Genetic Variation Affecting FSH Action

    PubMed Central

    Hagen, Casper P.; Sørensen, Kaspar; Aksglaede, Lise; Mouritsen, Annette; Mieritz, Mikkel G.; Tinggaard, Jeanette; Wohlfart-Veje, Christine; Petersen, Jørgen Holm; Main, Katharina M.; Meyts, Ewa Rajpert-De; Almstrup, Kristian; Juul, Anders

    2014-01-01

    Age at pubertal onset varies substantially in healthy girls. Although genetic factors are responsible for more than half of the phenotypic variation, only a small part has been attributed to specific genetic polymorphisms identified so far. Follicle-stimulating hormone (FSH) stimulates ovarian follicle maturation and estradiol synthesis which is responsible for breast development. We assessed the effect of three polymorphisms influencing FSH action on age at breast deveopment in a population-based cohort of 964 healthy girls. Girls homozygous for FSHR -29AA (reduced FSH receptor expression) entered puberty 7.4 (2.5–12.4) months later than carriers of the common variants FSHR -29GG+GA, p = 0.003. To our knowledge, this is the strongest genetic effect on age at pubertal onset in girls published to date. PMID:25231187

  10. Male pubertal development: are endocrine-disrupting compounds shifting the norms?

    PubMed

    2013-01-01

    Endocrine-disrupting compounds (EDCs) are synthetic or natural compounds that interfere with endogenous endocrine action. The frequent use of chemicals with endocrine active properties in household products and contamination of soil, water, and food sources by persistent chemical pollutants result in ubiquitous exposures. Wildlife observations and animal toxicological studies reveal adverse effects of EDCs on reproductive health.In humans, a growing number of epidemiological studies report an association with altered pubertal timing and progression. While these data are primarily reported in females,this review will focus on the small number of studies performed in males that report an association of polychlorinated biphenyls with earlier sexual maturity rating and confirm subtle effects of lead, dioxins, and endosulfan on delaying pubertal onset and progression in boys. Recent studies have also demonstrated that EDC exposure may affect pubertal testosterone production without having a noticeable effect on sexual maturity rating.A limitation to understand the effects of EDCs in humans is the potential for confounding due to the long temporal lag from early-life exposures to adult outcomes. The complex interplay of multiple environmental exposures over time also complicates the interpretation of human studies. These studies have identified critical windows of vulnerability during development when exposures to EDCs alter critical pathways and affect postnatal reproductive health. Contemporaneous exposures can also disrupt the hypothalamic-pituitary-gonadal axis. This paper will review the normal process of puberty in males and summarize human data that suggest potential perturbations in pubertal onset and tempo with early-life exposures to EDCs.

  11. Male pubertal development: are endocrine-disrupting compounds shifting the norms?

    PubMed

    Zawatski, William; Lee, Mary M

    2013-01-01

    Endocrine-disrupting compounds (EDCs) are synthetic or natural compounds that interfere with endogenous endocrine action. The frequent use of chemicals with endocrine active properties in household products and contamination of soil, water, and food sources by persistent chemical pollutants result in ubiquitous exposures. Wildlife observations and animal toxicological studies reveal adverse effects of EDCs on reproductive health. In humans, a growing number of epidemiological studies report an association with altered pubertal timing and progression. While these data are primarily reported in females, this review will focus on the small number of studies performed in males that report an association of polychlorinated biphenyls with earlier sexual maturity rating and confirm subtle effects of lead, dioxins, and endosulfan on delaying pubertal onset and progression in boys. Recent studies have also demonstrated that EDC exposure may affect pubertal testosterone production without having a noticeable effect on sexual maturity rating. A limitation to understand the effects of EDCs in humans is the potential for confounding due to the long temporal lag from early-life exposures to adult outcomes. The complex interplay of multiple environmental exposures over time also complicates the interpretation of human studies. These studies have identified critical windows of vulnerability during development when exposures to EDCs alter critical pathways and affect postnatal reproductive health. Contemporaneous exposures can also disrupt the hypothalamic-pituitary-gonadal axis. This paper will review the normal process of puberty in males and summarize human data that suggest potential perturbations in pubertal onset and tempo with early-life exposures to EDCs. PMID:23709001

  12. Male pubertal development: are endocrine-disrupting compounds shifting the norms?

    PubMed

    2013-01-01

    Endocrine-disrupting compounds (EDCs) are synthetic or natural compounds that interfere with endogenous endocrine action. The frequent use of chemicals with endocrine active properties in household products and contamination of soil, water, and food sources by persistent chemical pollutants result in ubiquitous exposures. Wildlife observations and animal toxicological studies reveal adverse effects of EDCs on reproductive health.In humans, a growing number of epidemiological studies report an association with altered pubertal timing and progression. While these data are primarily reported in females,this review will focus on the small number of studies performed in males that report an association of polychlorinated biphenyls with earlier sexual maturity rating and confirm subtle effects of lead, dioxins, and endosulfan on delaying pubertal onset and progression in boys. Recent studies have also demonstrated that EDC exposure may affect pubertal testosterone production without having a noticeable effect on sexual maturity rating.A limitation to understand the effects of EDCs in humans is the potential for confounding due to the long temporal lag from early-life exposures to adult outcomes. The complex interplay of multiple environmental exposures over time also complicates the interpretation of human studies. These studies have identified critical windows of vulnerability during development when exposures to EDCs alter critical pathways and affect postnatal reproductive health. Contemporaneous exposures can also disrupt the hypothalamic-pituitary-gonadal axis. This paper will review the normal process of puberty in males and summarize human data that suggest potential perturbations in pubertal onset and tempo with early-life exposures to EDCs. PMID:23977686

  13. Use of commercial and social sources of alcohol by underage drinkers: the role of pubertal timing.

    PubMed

    Storvoll, Elisabet E; Pape, Hilde; Rossow, Ingeborg

    2008-01-01

    We have explored whether alcohol use and procurement of alcohol from commercial and social sources vary with pubertal timing. A sub-sample of 9291 Norwegian minors (13-17 year-olds) was extracted from a nationwide school survey (response rate: 92%). Adolescents who had matured early (early developers, EDs) reported higher consumption and more alcohol-related harm than those who had matured late (late developers, LDs) or at the "normal" time (on time developers, ODs). Purchases from on-premise and off-premise outlets were much more important sources of alcohol for EDs than for ODs and LDs - both in relative and absolute terms. Moreover, EDs were somewhat more likely to obtain alcohol from social sources. Taken together, the findings indicate that adolescents who mature early have access to a larger variety of sources of alcohol than adolescents who mature later - which in turn may explain their increased level of drinking.

  14. On the leading edge; Combining maturity and advanced technology on the F404 turbofan engine

    SciTech Connect

    Powel, S.F. IV )

    1991-01-01

    In this paper the overall design concept of the F404 afterburning turbofan engine is reviewed together with some of the lessons learned from over 2 million flight hours in service. GE Aircraft Engines' derivative and growth plans for the F404 family are then reviewed including the Building Block component development approach. Examples of advanced technologies under development for introduction into new F404 derivative engine models are presented in the areas of materials, digital and fiber optic controls systems, and vectoring exhaust nozzles. The design concept and details of the F404-GE-402, F412-GE-400, and other derivative engines under full-scale development are described. Studies for future growth variants and the benefits of the F404 derivative approach to development of afterburning engines in the 18,000-24,000 lb (80--107 kN) thrust class and non- afterburning engines in the 12,000--19,000 lb (53--85 kN) class are discussed.

  15. Disturbance of pubertal development after cancer treatment.

    PubMed

    Müller, Jørn

    2002-03-01

    Chemotherapy and irradiation to the hypothalamic-pituitary-gonadal axis given for childhood cancer carry with them a risk of endocrine late effects. These treatment modalities are part of the treatment of common oncological diseases in childhood such as acute lymphoblastic leukaemia, brain tumours, Hodgkins lymphoma and solid tumours outside the central nervous system. Cranial irradiation of a prepubertal child can induce early or even precocious puberty, particularly in girls. Hypogonadotrophic hypogonadism may develop at a later stage. Irradiation of the gonads, as e.g. part of total body irradiation before bone marrow transplantation, will most likely cause gonadal failure and late, incomplete or absent puberty in girls. Many boys will experience a normal pubertal development except for small testes. Alkylating agents given for a variety of childhood cancers, are gonadotoxic. After high doses of these drugs, girls are at great risk of developing ovarian failure, whereas boys will usually go through puberty normally. Many children receive a combination of several treatment modalities, which complicates the prediction of pubertal development. Control and management of children with cancer at risk of having a disturbance of puberty is difficult and requires detailed knowledge of endocrinology as well as oncology. This chapter reviews the common treatments for the most frequent childhood cancers, the known effects of the therapy on pubertal development and provides outlines of control and management.

  16. Circadian activity rhythm in pre-pubertal and pubertal marmosets (Callithrix jacchus) living in family groups.

    PubMed

    Melo, Paula R; Gonçalves, Bruno S B; Menezes, Alexandre A L; Azevedo, Carolina V M

    2016-03-01

    In marmosets, a phase advance was observed in activity onset in pubertal animals living in captivity under semi-natural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂ and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythm in marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm. PMID:26724713

  17. Circadian activity rhythm in pre-pubertal and pubertal marmosets (Callithrix jacchus) living in family groups.

    PubMed

    Melo, Paula R; Gonçalves, Bruno S B; Menezes, Alexandre A L; Azevedo, Carolina V M

    2016-03-01

    In marmosets, a phase advance was observed in activity onset in pubertal animals living in captivity under semi-natural conditions which had stronger correlation with the times of sunrise over the course of the year than the age of the animal. In order to evaluate the effect of puberty on the circadian activity rhythm in male and female marmosets living in family groups in controlled lighting conditions, the activity of 5 dyads of twins (4 ♀/♂ and 1 ♂/♂) and their respective parents was continuously monitored by actiwatches between the 4th and 12th months of age. The families were kept under LD 12:12 h with constant humidity and temperature. The onset of puberty was identified by monitoring fecal steroids. Juveniles showed higher totals of daily activity and differences in the daily distribution of activity in relation to parents, in which the bimodal profile was characterized by higher levels in evening activity in relation to morning activity. Regarding the phase, the activity onset and offset, occurred later in relation to parents. After entering puberty, the activity onset and offset occurred later and there was an increase in total daily activity. On the other hand, when assessing the effect of sex, only females showed a delay in the activity offset and an increase in total daily activity. Therefore, the circadian activity rhythm in marmosets has peculiar characteristics in the juvenile stage in relation to the total of daily activity, the onset and offset of the active phase, and the distribution of activity during this phase. Besides, the entering puberty was associated with a phase delay and increase on total daily activity, with differences between sexes, possibly due to hormonal influences and/or social modulation on rhythm.

  18. Consequences of Early Life Programing by Genetic and Environmental Influences: A Synthesis Regarding Pubertal Timing.

    PubMed

    Roth, Christian L; DiVall, Sara

    2016-01-01

    Sexual maturation is closely tied to growth and body weight gain, suggesting that regulative metabolic pathways are shared between somatic and pubertal development. The pre- and postnatal environment affects both growth and pubertal development, indicating that common pathways are affected by the environment. Intrauterine and early infantile developmental phases are characterized by high plasticity and thereby susceptibility to factors that affect metabolic function as well as related reproductive function throughout life. In children born small for gestational age, poor nutritional conditions during gestation can modify metabolic systems to adapt to expectations of chronic undernutrition. These children are potentially poorly equipped to cope with energy-dense diets and are possibly programmed to store as much energy as possible, causing rapid weight gain with the risk for adult disease and premature onset of puberty. Environmental factors can cause modifications to the genome, so-called epigenetic changes, to affect gene expression and subsequently modify phenotypic expression of genomic information. Epigenetic modifications, which occur in children born small for gestational age, are thought to underlie part of the metabolic programming that subsequently effects both somatic and pubertal development. PMID:26680576

  19. The Developmental Pathway From Pubertal Timing to Delinquency and Sexual Activity From Early to Late Adolescence

    PubMed Central

    Negriff, Sonya; Elizabeth, J. Susman; Trickett, Penelope K.

    2013-01-01

    There is strong evidence that early pubertal timing is associated with adolescent problem behaviors. However, there has been limited investigation of the mechanisms or developmental relationships. The present study examined longitudinal models incorporating pubertal timing, delinquency, and sexual activity in a sample of 454 adolescents (9–13 years old at enrollment; 47% females). Participants were seen for three assessments approximately 1 year apart. Characteristics of friendship networks (older friends, male friends, older male friends) were examined as mediators. Structural equation modeling was used to test these associations as well as temporal relationships between sexual activity and delinquency. Results showed that early pubertal timing at Time 1 was related to more sexual activity at Time 2, which was related to higher delinquency at Time 3, a trend mediation effect. None of the friendship variables mediated these associations. Gender or maltreatment status did not moderate the meditational pathways. The results also supported the temporal sequence of sexual activity preceding increases in delinquency. These findings reveal that early maturing adolescents may actively seek out opportunities to engage in sexual activity which appears to be risk for subsequent delinquency. PMID:21191640

  20. The developmental pathway from pubertal timing to delinquency and sexual activity from early to late adolescence.

    PubMed

    Negriff, Sonya; Susman, Elizabeth J; Trickett, Penelope K

    2011-10-01

    There is strong evidence that early pubertal timing is associated with adolescent problem behaviors. However, there has been limited investigation of the mechanisms or developmental relationships. The present study examined longitudinal models incorporating pubertal timing, delinquency, and sexual activity in a sample of 454 adolescents (9-13 years old at enrollment; 47% females). Participants were seen for three assessments approximately 1 year apart. Characteristics of friendship networks (older friends, male friends, older male friends) were examined as mediators. Structural equation modeling was used to test these associations as well as temporal relationships between sexual activity and delinquency. Results showed that early pubertal timing at Time 1 was related to more sexual activity at Time 2, which was related to higher delinquency at Time 3, a trend mediation effect. None of the friendship variables mediated these associations. Gender or maltreatment status did not moderate the meditational pathways. The results also supported the temporal sequence of sexual activity preceding increases in delinquency. These findings reveal that early maturing adolescents may actively seek out opportunities to engage in sexual activity which appears to be risk for subsequent delinquency. PMID:21191640

  1. Chemical and nanometer-scale structure of kerogen and its change during thermal maturation investigated by advanced solid-state 13C NMR spectroscopy

    USGS Publications Warehouse

    Mao, J.; Fang, X.; Lan, Y.; Schimmelmann, A.; Mastalerz, Maria; Xu, L.; Schmidt-Rohr, K.

    2010-01-01

    We have used advanced and quantitative solid-state nuclear magnetic resonance (NMR) techniques to investigate structural changes in a series of type II kerogen samples from the New Albany Shale across a range of maturity (vitrinite reflectance R0 from 0.29% to 1.27%). Specific functional groups such as CH3, CH2, alkyl CH, aromatic CH, aromatic C-O, and other nonprotonated aromatics, as well as "oil prone" and "gas prone" carbons, have been quantified by 13C NMR; atomic H/C and O/C ratios calculated from the NMR data agree with elemental analysis. Relationships between NMR structural parameters and vitrinite reflectance, a proxy for thermal maturity, were evaluated. The aromatic cluster size is probed in terms of the fraction of aromatic carbons that are protonated (???30%) and the average distance of aromatic C from the nearest protons in long-range H-C dephasing, both of which do not increase much with maturation, in spite of a great increase in aromaticity. The aromatic clusters in the most mature sample consist of ???30 carbons, and of ???20 carbons in the least mature samples. Proof of many links between alkyl chains and aromatic rings is provided by short-range and long-range 1H-13C correlation NMR. The alkyl segments provide most H in the samples; even at a carbon aromaticity of 83%, the fraction of aromatic H is only 38%. While aromaticity increases with thermal maturity, most other NMR structural parameters, including the aromatic C-O fractions, decrease. Aromaticity is confirmed as an excellent NMR structural parameter for assessing thermal maturity. In this series of samples, thermal maturation mostly increases aromaticity by reducing the length of the alkyl chains attached to the aromatic cores, not by pronounced growth of the size of the fused aromatic ring clusters. ?? 2010 Elsevier Ltd. All rights reserved.

  2. Fathers and Their Adolescent Sons: Pubertal Development and Paternal Involvement.

    ERIC Educational Resources Information Center

    Ogletree, Mark D.; Jones, Randall M.; Coyl, Diana, D.

    2002-01-01

    Examined the relation between pubertal transition and qualitative aspects of the father-son relationship through a survey of 173 adolescent males and 122 fathers. Assessed physical affection, general support, companionship, and sustained contact over three levels of pubertal development. Found that perception of physical affection was the only…

  3. Pubertal Timing and Adolescent Sexual Behavior in Girls

    ERIC Educational Resources Information Center

    Moore, Sarah R.; Harden, K. Paige; Mendle, Jane

    2014-01-01

    Girls who experience earlier pubertal timing relative to peers also exhibit earlier timing of sexual intercourse and more unstable sexual relationships. Although pubertal development initiates feelings of physical desire, the transition into romantic and sexual relationships involves complex biological and social processes contributing both to…

  4. Familial cytomegalic adrenocortical hypoplasia: an X-linked syndrome of pubertal failure.

    PubMed Central

    Hay, I D; Smail, P J; Forsyth, C C

    1981-01-01

    Five boys with familial cytomegalic adrenocortical hypoplasia have been followed up for an average of 19 years. Despite treatment with replacement corticosteroids, all 5 failed to show a spontaneous onset of puberty and, when assessed at ages 13 to 19 years, all had both sexual infantilism and skeletal immaturity. Hypogonadism was confirmed by low levels of plasma testosterone, and pituitary reserve of gonadotrophin was shown to be inadequate by testing with gonadotrophin-releasing hormone. Two boys, both with adequate testosterone output on human chorionic gonadotrophin stimulation, were given gonadotrophin therapy, whereas the other 3 were treated with parenterally administered testosterone. With treatment, all 5 patients showed advances in pubertal staging. Although the mechanism of the hypogonadotropism remains unclear, the association of hypogonadotrophic hypogonadism with familial cytomegalic adrenocortical hypoplasia appears to be a constant one and may be considered as a treatable inherited syndrome of pubertal failure. PMID:7197507

  5. Mature autologous dendritic cell vaccines in advanced non-small cell lung cancer: a phase I pilot study

    PubMed Central

    2011-01-01

    Background Overall therapeutic outcomes of advanced non-small-cell lung cancer (NSCLC) are poor. The dendritic cell (DC) immunotherapy has been developed as a new strategy for the treatment of lung cancer. The purpose of this study was to evaluate the feasibility, safety and immunologic responses in use in mature, antigen-pulsed autologous DC vaccine in NSCLC patients. Methods Five HLA-A2 patients with inoperable stage III or IV NSCLC were selected to receive two doses of 5 × 107 DC cells administered subcutaneous and intravenously two times at two week intervals. The immunologic response, safety and tolerability to the vaccine were evaluated by the lymphoproliferation assay and clinical and laboratorial evolution, respectively. Results The dose of the vaccine has shown to be safe and well tolerated. The lymphoproliferation assay showed an improvement in the specific immune response after the immunization, with a significant response after the second dose (p = 0.005). This response was not long lasting and a tendency to reduction two weeks after the second dose of the vaccine was observed. Two patients had a survival almost twice greater than the expected average and were the only ones that expressed HER-2 and CEA together. Conclusion Despite the small sample size, the results on the immune response, safety and tolerability, combined with the results of other studies, are encouraging to the conduction of a large clinical trial with multiples doses in patients with early lung cancer who underwent surgical treatment. Trial Registration Current Controlled Trials: ISRCTN45563569 PMID:21682877

  6. Defining the Boundaries of Early Adolescence: A User's Guide to Assessing Pubertal Status and Pubertal Timing in Research with Adolescents

    ERIC Educational Resources Information Center

    Dorn, Lorah D.; Dahl, Ronald E.; Woodward, Hermi Rojahn; Biro, Frank

    2006-01-01

    This article addresses pragmatic issues regarding the assessment of puberty in research on adolescent health and development. Because pubertal processes have a major effect on physical, psychological, and social development, we posit that the assessment of pubertal status is at least as important as the specification of age for characterizing…

  7. Maturational Rate of Tokyo Children with and without Mental Retardation.

    ERIC Educational Resources Information Center

    Lindgren, Gunilla W.; Katoda, Hiroshi

    1993-01-01

    Comparison of growth rates and menarcheal age for groups of boys and girls, ages 6 to 15, in Tokyo (Japan) found that children with mental retardation had a smaller growth spurt during puberty but did not differ in maturational rate defined by age at pubertal height spurt or age at menarche. (Author/DB)

  8. Two leptin genes and a leptin receptor gene of female chub mackerel (Scomber japonicus): Molecular cloning, tissue distribution and expression in different obesity indices and pubertal stages.

    PubMed

    Ohga, Hirofumi; Matsumori, Kojiro; Kodama, Ryoko; Kitano, Hajime; Nagano, Naoki; Yamaguchi, Akihiko; Matsuyama, Michiya

    2015-10-01

    Leptin is a hormone produced by fat cells that regulates the amount of fat stored in the body and conveys nutritional status to the reproductive axis in mammals. In the present study we identified two subtypes of leptin genes (lepa and lepb) and a leptin receptor gene (lepr) from chub mackerel (Scomber japonicus) and there gene expression under different feeding conditions (control and high-feed) and pubertal development stages was analyzed using quantitative real-time PCR. The protein lengths of LepA, LepB and LepR were 161 amino acids (aa), 163 aa and 1149 aa, respectively and both leptin subtypes shared only 15% similarity in aa sequences. In pubertal females, lepa was expressed in the brain, pituitary gland, liver, adipose tissue and ovary; however, in adult (gonadal maturation after the second in the life) females, lepa was expressed only in the liver. lepb was expressed primarily in the brain of all fish tested and was expressed strongly in the adipose tissue of adults. lepr was characterized by expression in the pituitary. The high-feed group showed a high conditioning factor level; unexpectedly, hepatic lepa and brain lepr were significantly more weakly expressed compared with the control-feed group. Furthermore, the expression levels of lepa, lepb and lepr genes showed no significant differences between pre-pubertal and post-pubertal fish. On the other hand, pituitary fshβ and lhβ showed no significant differences between different feeding groups of pre-pubertal fish. In contrast, fshβ and lhβ expressed abundantly in the post-pubertal fish of control feed group. Based on these results, whether leptin plays an important role in the nutritional status and pubertal onset of chub mackerel remains unknown.

  9. Pubertal status associations with reward and threat sensitivities and subcortical brain volumes during adolescence.

    PubMed

    Urošević, Snežana; Collins, Paul; Muetzel, Ryan; Lim, Kelvin O; Luciana, Monica

    2014-08-01

    Adolescence is characterized by complex developmental processes that impact behavior, biology, and social functioning. Two such adolescence-specific processes are puberty and increases in reward sensitivity. Relations between these processes are poorly understood. The present study focused on examining unique effects of puberty, age, and sex on reward and threat sensitivities and volumes of subcortical brain structures relevant for reward/threat processing in a healthy sample of 9-18year-olds. Unlike age, pubertal status had a significant unique positive relationship with reward sensitivity. In addition, there was a trend for adolescent females to exhibit higher threat sensitivity with more advanced pubertal development and higher reward and threat sensitivity with older age. Similarly, there were significant puberty by sex interaction effects on striatal volumes, i.e., left nucleus accumbens and right pallidum. The present pattern of results suggests that pubertal development, independent of chronological age, is uniquely associated with reward hypersensitivity and with structural differences in striatal regions implicated in reward processing. PMID:24512818

  10. Pubertal Status Associations with Reward and Threat Sensitivities and Subcortical Brain Volumes during Adolescence

    PubMed Central

    Urošević, Snežana; Collins, Paul; Muetzel, Ryan; Lim, Kelvin O.; Luciana, Monica

    2014-01-01

    Adolescence is characterized by complex developmental processes that impact behavior, biology, and social functioning. Two such adolescence-specific processes are puberty and increases in reward sensitivity. Relations between these processes are poorly understood. The present study focused on examining unique effects of puberty, age, and sex on reward and threat sensitivities and volumes of subcortical brain structures relevant for reward/threat processing in a healthy sample of 9 to 18 year-olds. Unlike age, pubertal status had a significant unique positive relationship with reward sensitivity. In addition, there was a trend for adolescent females to exhibit higher threat sensitivity with more advanced pubertal development and higher reward and threat sensitivity with older age. Similarly, there were significant puberty by sex interaction effects on striatal volumes, i.e., left nucleus accumbens and right pallidum. The present pattern of results suggests that pubertal development, independent of chronological age, is uniquely associated with reward hypersensitivity and with structural differences in striatal regions implicated in reward processing. PMID:24512818

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

    PubMed

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

    2011-02-01

    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. In addition, the mechanism linking early pubertal timing to delinquency differs depending on maltreatment experience. PMID:21262055

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

    PubMed Central

    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

  13. Oestrogenic mycotoxin exposures and precocious pubertal development.

    PubMed

    Massart, F; Saggese, G

    2010-04-01

    Since the 1970s, there has been a worldwide scientific discussion on the potential health consequences of human exposure to endocrine disrupters: many environmentally persistent compounds are oestrogen agonists and/or androgen antagonists. Thus, they can dysregulate the hypothalamic-pituitary-gonadal axis potentially affecting human puberty timing. Zearalenone (ZEA) is a non-steroidal mycotoxin produced by Fusarium species on several grains. Despite its low acute toxicity and carcinogenicity, ZEA exhibits oestrogenic and anabolic properties in several animal species. ZEA food contamination is caused either by direct contamination of grains, fruits and their based-products or by 'carry-over' of mycotoxins in animal tissues, milk and eggs after intake of contaminated feedstuff. In addition, zeranol (alpha-ZAL), a resorcyl lactone derived from ZEA, has been widely used in the USA as a growth promoter to improve fattening rates in cattle. From 1978 to 1984, a great epidemic of premature thelarche and precocious puberty occurred in Puerto Rico. To explain this condition, it was suggested that dairy and meat products could be contaminated with anabolic oestrogens such as ZEA or alpha-ZAL. Subsequently, worldwide other groups have also reported causative associations between oestrogenic mycotoxins and development of early thelarche and/or precocious puberty in exposed children. In addition to animal data, epidemiological studies strongly support the hypothesis that human pubertal development may be induced by foetal/early or prepubertal exposure to oestrogenic compounds. Indeed, ZEA and its metabolites are able to adopt molecular conformation, which sufficiently resembles 17beta-oestradiol to allow it to bind to oestrogen receptors (ERs) in target cells exerting oestrogenic (agonist) actions. In this view, oestrogenic mycotoxins are suspected as triggering factor for precocious pubertal development at least in prepubertal exposed girls.

  14. Environmental phenols and pubertal development in girls.

    PubMed

    Wolff, Mary S; Teitelbaum, Susan L; McGovern, Kathleen; Pinney, Susan M; Windham, Gayle C; Galvez, Maida; Pajak, Ashley; Rybak, Michael; Calafat, Antonia M; Kushi, Lawrence H; Biro, Frank M

    2015-11-01

    Environmental exposures to many phenols are documented worldwide and exposures can be quite high (>1 μM of urine metabolites). Phenols have a range of hormonal activity, but knowledge of effects on child reproductive development is limited, coming mostly from cross-sectional studies. We undertook a prospective study of pubertal development among 1239 girls recruited at three U.S. sites when they were 6-8 years old and were followed annually for 7 years to determine age at first breast or pubic hair development. Ten phenols were measured in urine collected at enrollment (benzophenone-3, enterolactone, bisphenol A, three parabens (methyl-, ethyl-, propyl-), 2,5-dichlorophenol, triclosan, genistein, daidzein). We used multivariable adjusted Cox proportional hazards ratios (HR (95% confidence intervals)) and Kaplan-Meier survival analyses to estimate relative risk of earlier or later age at puberty associated with phenol exposures. For enterolactone and benzophenone-3, girls experienced breast development 5-6 months later, adjusted HR 0.79 (0.64-0.98) and HR 0.80 (0.65-0.98) respectively for the 5th vs 1st quintiles of urinary biomarkers (μg/g-creatinine). Earlier breast development was seen for triclosan and 2,5-dichlorophenol: 4-9 months sooner for 5th vs 1st quintiles of urinary concentrations (HR 1.17 (0.96-1.43) and HR 1.37 (1.09-1.72), respectively). Association of breast development with enterolactone, but not the other three phenols, was mediated by body size. These phenols may be antiadipogens (benzophenone-3 and enterolactone) or thyroid agonists (triclosan and 2,5-dichlorophenol), and their ubiquity and relatively high levels in children would benefit from further investigation to confirm these findings and to establish whether there are certain windows of susceptibility during which exposure can affect pubertal development.

  15. Evaluation of skeletal maturation using mandibular third molar development in Indian adolescents

    PubMed Central

    Mehta, Nishit; Patel, Dolly; Mehta, Falguni; Gupta, Bhaskar; Zaveri, Grishma; Shah, Unnati

    2016-01-01

    Objective: This study was done with the following objectives: to estimate dental maturity using the Demirjian Index (DI) for the mandibular third molar; to investigate the relationship between dental maturity and skeletal maturity among growing patients; to evaluate the use of the mandibular third molar as an adjunctive tool for adolescent growth assessment in combination with the cervical vertebrae; to evaluate the clinical value of the third molar as a growth evaluation index. Materials and Methods: Samples were derived from panoramic radiographs and lateral cephalograms of 615 subjects (300 males and 315 females) of ages ranging 9-18 years, and estimates of dental maturity (DI) and skeletal maturity [cervical vertebrae maturation indicators (CVMI)] were made. Results: A highly significant association (r = 0.81 for males and r = 0.72 for females) was found between DI and CVMI. DI Stage B corresponded to Stage 2 of CVMI (prepeak of pubertal growth spurt) in both sexes. In males, DI stages C and D represent the peak of the pubertal growth spurt. In females, stages B and C show that the peak of the pubertal growth spurt has not been passed. DI stage E in females and DI Stage F in males correlate that the peak of the pubertal growth spurt has been passed. Conclusion: A highly significant association exists between DI and CVMI. Mandibular third molar DI stages are reliable adjunctive indicators of skeletal maturity. PMID:27555733

  16. Pre-menarche pubertal development following unique form of immigration: the case of girls adopted from China.

    PubMed

    Tan, Tony Xing; Camras, Linda A

    2015-02-01

    Our study tested the hypothesis that drastic social-cultural change has an impact on girls' pre-menarche pubertal development. We focused on a unique group of Chinese immigrants who migrated out of China in infancy through international adoption. Our sample included 298 Chinese girls who were 7.3-11.1 years in 2011 (Mean = 8.8, SD = 0.9) and were adopted at 7-24 months (Mean = 12.6, SD = 3.4). We found that 34% showed at least one of four signs of pubertal development: Growth spurt, body fat increase, breast development, and body hair. Logistic regression analyses showed that the odds of growth spurt was raised by the girls' age in 2011, behavior problems in 2005, but lowered by the adoptive families' household income; the odds of body fat increase in 2011 was raised by the adopted Chinese girls' weight in 2007 and behavior problems in 2005, but was lowered by the adoptive mother's education level; the odds for breast development in 2011 was raised by the girls' age in 2011, weight in 2007, and behavior problems in 2009. For body hair, none of the factors predicted the odds. Prevalence of precocious puberty, based on the criterion of breast development before 8 years, was 3.5%. Overall, our study suggests that the pre-menarche pubertal development of adopted Chinese girls may be slightly advanced but also is affected by factors that affect non-adopted girls' pubertal development.

  17. Phthalate exposure and pubertal development in a longitudinal study of US girls

    PubMed Central

    Wolff, M.S.; Teitelbaum, S.L.; McGovern, K.; Windham, G.C.; Pinney, S.M.; Galvez, M.; Calafat, A.M.; Kushi, L.H.; Biro, F.M.

    2014-01-01

    -molecular weight phthalate urinary metabolite concentrations and age at pubertal transition in adjusted analyses. LIMITATIONS, REASONS FOR CAUTION While there is evidence that phthalate exposures are fairly consistent over time, the exposure measure in this study may not reflect an earlier, more susceptible window of exposure. We investigated alternative explanations that might arise from exposure misclassification or confounding. WIDER IMPLICATIONS OF THE FINDINGS Phthalates are widespread, hormonally active pollutants that may alter pubertal timing. Whether exposures delay or accelerate pubertal development may depend on age at exposure as well as other factors such as obesity and exposures earlier in life. Whether exposures act independently or as part of real life mixtures may also change their effects on maturation from birth through childhood. STUDY FUNDING/COMPETING INTEREST(S) This project was supported by the US National Institutes of Health, Environmental Protection Agency, New York State Empire Clinical Research Investigator Program and the Avon Foundation. L.H.K. is employed by Kaiser Permanente. The remaining authors declare they have no actual or potential competing financial interests. PMID:24781428

  18. Adrenarche and skeletal maturation during luteinizing hormone releasing hormone analogue suppression of gonadarche.

    PubMed Central

    Wierman, M E; Beardsworth, D E; Crawford, J D; Crigler, J F; Mansfield, M J; Bode, H H; Boepple, P A; Kushner, D C; Crowley, W F

    1986-01-01

    During puberty the effects of adrenal androgens upon skeletal maturation are obscured by the influence of gonadal steroids. Suppression of gonadarche with an analogue of luteinizing hormone releasing hormone (LHRHa) affords an opportunity to examine the onset and progression of adrenarche in the absence of pubertal levels of gonadal steroids in a controlled fashion and to explore the relationship between adrenal androgens and the rate of epiphyseal maturation. In 29 children with central precocious puberty, gonadarche was suppressed with LHRHa administration for 1-4 yr. During LHRHa exposure, dehydroepiandrosterone sulfate (DHAS) levels, as an index of adrenal maturation, were constant or increased in an age-expected manner. The change in bone age for change in chronologic age decreased from 1.7 +/- 0.1 to 0.49 +/- 0.05 (P = 0.00005), indicating that the LHRHa-induced return to a prepubertal gonadal steroid environment was associated with a slowing of skeletal maturation. DHAS levels were correlated with the rate of skeletal advancement before (r = 0.57, P = 0.001) and during 12 to 48 mo of exposure to LHRHa (r = 0.52, P = 0.003). A negative correlation of DHAS values with subsequent increases in predicted mature height was observed (r = -0.49, P = 0.007). Thus, in children with central precocious puberty, adrenarche progressed normally during LHRHa suppression of gonadarche. In children with the onset of progression of adrenarche during maintenance of a prepubertal gonadal steroid milieu, there was less evidence than in preadrenarchal children of a restraint upon skeletal maturation. These data suggest that adrenal androgens contribute importantly to epiphyseal advancement during childhood. PMID:2935557

  19. Pubertal and adult Leydig cell function in Mullerian inhibiting substance-deficient mice.

    PubMed

    Wu, Xiufeng; Arumugam, Ramamani; Baker, Stephen P; Lee, Mary M

    2005-02-01

    Mullerian inhibiting substance (MIS) causes Mullerian duct regression during sexual differentiation and regulates postnatal Leydig cell development. MIS knockout (MIS-KO) mice with targeted deletions of MIS develop Leydig cell hyperplasia, but their circulating androgen concentrations are reportedly unaltered. We compared reproductive hormone profiles, androgen biosynthesis, and the expression of key steroidogenic and metabolic enzymes in MIS-KO and wild-type (WT) mice at puberty (36 d) and sexual maturity (60 d). In pubertal animals, basal testosterone and LH concentrations in plasma were lower in MIS-KO than WT mice, whereas human chorionic gonadotropin-stimulated testosterone concentrations were similar. In adults, basal LH, and both basal and human chorionic gonadotropin (hCG)-stimulated testosterone concentrations were similar. Purified Leydig cells from pubertal MIS-KO mice had lower testosterone but higher androstanediol and androstenedione production rates. In contrast, testosterone, androstanediol, and androstenedione production rates were all lower in adult MIS-KO Leydig cells. Steroidogenic acute regulatory protein expression was lower in pubertal MIS-KO mice compared with WT, whereas 17beta-hydroxy-steroid dehydrogenase and 5alpha-reductase were greater, and P450c17 and P450scc were similar. The expression of steroidogenic acute regulatory protein and 17beta-hydroxysteroid dehydrogenase was lower in adult MIS-KO mice, whereas that of 5alpha-reductase, P450c17, and P450scc was similar. Collectively, these results suggest that in the absence of MIS, Leydig cells remain less differentiated, causing an altered intratesticular androgen milieu that may contribute to the infertility of MIS-KO mice. In immature mice, this deficit in steroidogenic capacity appears to be mediated by a direct loss of MIS action in Leydig cells as well as by indirect effects via the hypothalamic-pituitary-gonadal axis.

  20. Advancement of reproductive activity, seasonal reduction in prolactin secretion and seasonal pelage changes in pubertal red deer hinds (Cervus elaphus) subjected to artificially shortened daily photoperiod or daily melatonin treatments.

    PubMed

    Webster, J R; Barrell, G K

    1985-01-01

    Prepubertal red deer hinds were subjected to shortened daily photoperiod (8 h light per day, N = 3) or a daily (afternoon) melatonin injection (N = 4) for 83 days starting on 8 January, 2 weeks after the summer solstice. Compared with control hinds (N = 3) these treatments caused premature moulting of summer pelage, reduced serum prolactin concentrations to barely detectable levels about 34 days earlier than usual and advanced the date of mating. Calves were born earlier (P less than 0.005) in the hinds exposed to a shortened photoperiod (12 November +/- 1.7 days) and melatonin treatment (11 November +/- 3.2 days) than in control hinds (13 December +/- 7.9 days). Serum progesterone levels recorded before the first detected oestrus indicated that silent ovulations had occurred in many of the hinds (6 of 10) in this experiment. This study demonstrated the role of shortened daily photoperiod in red deer and indicated that the effects of reduced photoperiod observed were mediated by melatonin. PMID:3968657

  1. Growth and pubertal development in children and adolescents: effects of diet and physical activity.

    PubMed

    Rogol, A D; Clark, P A; Roemmich, J N

    2000-08-01

    The longitudinal growth of an individual child is a dynamic statement of the general health of that child. Measurements should be performed often and accurately to detect alterations from physiologic growth. Although any single point on the growth chart is not very informative, when several growth points are plotted over time, it should become apparent whether that individual's growth is average, a variant of the norm, or pathologic. Somatic growth and maturation are influenced by several factors that act independently or in concert to modify an individual's genetic growth potential. Linear growth within the first 2 y of life generally decelerates but then remains relatively constant throughout childhood until the onset of the pubertal growth spurt. Because of the wide variation among individuals in the timing of the pubertal growth spurt, there is a wide range of physiologic variations in normal growth. Nutritional status and heavy exercise training are only 2 of the major influences on the linear growth of children. In the United States, nutritional deficits result from self-induced restriction of energy intake. That single factor, added to the marked energy expenditure of training and competition for some sports, and in concert with the self-selection of certain body types, makes it difficult to identify the individual factors responsible for the slow linear growth of some adolescent athletes, for example, those who partake in gymnastics, dance, or wrestling. PMID:10919954

  2. Effect of one or two pre-pubertal long days on age at first egg in domestic pullets.

    PubMed

    Lewis, P D; Gous, R M

    2004-02-01

    1. Two trials were conducted, using 288 brown-egg hybrid pullets in each, to determine the effect on age at first egg (AFE) of exposure to one or two 'long days' during the rearing period. In the first trial, birds were given a single 'long day' of 10, 12 or 14 h at 75, 89 or 103 d of age, with controls maintained on 8-h photoperiods. All treatment groups were transferred to cages at 110 d, and half the birds from each treatment combination given a 6-h increment in photoperiod at 116 d, with the remainder held on 8-h photoperiods. In the other trial, birds were given one or two long days of 14 or 16 h at 96, 107, 117 or 128 d of age; controls were again held on 8-h photoperiods. All groups were moved to cages at 130 d but maintained on 8-h photoperiods. 2. AFE was not significantly affected by one or two pre-pubertal long days, irrespective of when the long day was given or its length. AFE was advanced by 2 to 3 weeks following a transfer from 8 to 14 h at 116 d, independently of whether or not the birds had received a previous long day exposure. 3. It appears that a full-fed egg-type hybrid requires more than two cycles of long days to initiate rapid gonadal development, and that exposure to a single long day during the rearing period will have minimal effect on the timing of sexual maturation and no influence on the response to a subsequent permanent transfer to long days.

  3. Late maturers at a performance disadvantage to their more mature peers in junior Australian football.

    PubMed

    Gastin, Paul B; Bennett, Gary

    2014-01-01

    Children and adolescents mature at different rates such that individuals competing in the same competition may differ in physical and biological maturity despite being of similar chronological age. Whether or not differences translate into on-field performance in competition is relatively unknown. This study investigated the influence of biological maturity on fitness and match running performance in junior Australian football. Eighty-seven under-15 years players were categorised into early (n = 20), average (n = 45) and late (n = 22) maturity groups based on self-reported and anthropometric assessment of biological maturity. Running movements during competition were collected using GPS (5 Hz) technology. Early maturers were heavier and taller than all other boys (P < 0.05), while biological maturity was significantly correlated to 20 m sprint (r = 0.53, P < 0.01). Total distance, high-intensity (>14.4 km · h(-1)) running distance and number of high-intensity efforts were significantly greater (20.8%, 53.6%, 31.7%, respectively; P < 0.01) in early compared to late maturers. Number of sprints and peak speed in competition were not different. Pubertal development and maturity status partially explained the differences between players in physical size, functional running fitness and match running performance. Late maturing players in this Australian football under-15 age group were at a physical and performance disadvantage to their earlier maturing peers.

  4. Sexual Dimorphisms in the Associations of BMI and Body Fat with Indices of Pubertal Development in Girls and Boys

    PubMed Central

    Crocker, Melissa K.; Stern, Elizabeth A.; Sedaka, Nicole M.; Shomaker, Lauren B.; Brady, Sheila M.; Ali, Asem H.; Shawker, Thomas H.; Hubbard, Van S.

    2014-01-01

    Context: The effect of obesity and concomitant insulin resistance on pubertal development is incompletely elucidated. Objective: To determine how measures of adiposity and insulin resistance are associated with pubertal maturation in boys and girls. Setting and Design: Breast and pubic hair Tanner stage and testicular volume by orchidometry were determined by physical examination in 1066 children. Ovarian volume was estimated by trans-abdominal ultrasound. Fat mass, skeletal age, and fasting serum for insulin and glucose, total T, estradiol, estrone, dehydroepiandrosterone-sulfate, and androstenedione were measured at the National Institutes of Health Clinical Research Center. Convenience sample; 52% obese, 59% female. Results: Logistic regression identified a significant interaction between sex and obesity for prediction of pubertal development (P ≤ .01). There was a negative association between boys' testicular volume and body mass index (BMI)/fat mass but a positive association between girls' breast stage and BMI/fat mass. Ovarian volume in girls was positively associated with insulin resistance but not with BMI/fat mass. There was a positive association between obesity and measures of estrogen exposure (breast development and skeletal age) in both sexes. Positive correlations were seen for girls between BMI and pubic hair development and between insulin resistance and T production, whereas adiposity was negatively associated with pubic hair in boys. Conclusions: Significant sexual dimorphisms in the manifestations of pubertal development are seen in obese girls and boys. Two known effects of obesity, increased peripheral conversion of low-potency androgens to estrogens by adipose tissue-aromatase and increased insulin resistance, may be in large part responsible for these differences. PMID:24780051

  5. Neonatal and Pubertal Development in Males of a Cooperatively Breeding Primate, the Cotton-Top Tamarin (Saguinus oedipus oedipus)1

    PubMed Central

    Ginther, Anita J.; Carlson, Anne A.; Ziegler, Toni E.; Snowdon, Charles T.

    2006-01-01

    In cooperatively breeding groups of mammals, reproduction is usually restricted to a small number of individuals within the social group. Sexual development of mammals can be affected by social environment, but we know little regarding effects of the cooperative-breeding system on males. Cotton-top tamarin (Saguinus oedipus oedipus) offspring typically do not reproduce in their natal group, even though they may be physically mature. We examined neonatal and pubertal development in captive male cotton-top tamarins as an example of reproductive development within a cooperative-breeding system and to compare cotton-top tamarins with the general primate model. Puberty was characterized using both hormonal and physical measures. Data were collected on urinary levels of LH, testosterone (T), dihydrotestosterone (DHT), cortisol, and the ratio of DHT to T; testicular development; body weight; and breeding age. We determined that 1) pubertal LH secretion began at Week 37, 2) a surge of T secretion followed at Weeks 41–44, and 3) an increase in the metabolism of T to DHT may have occurred at an average age of 48.6 wk. Most of the rapid weight gain was completed by Week 24, before hormonal increases and rapid scrotal growth. We concluded that rapid pubertal testicular growth in captive cotton-top males was completed by an average 76 wk, but that completion of the individual pubertal spurt can occur between 56 and 122 wk. In a cooperative-breeding system, the opportunity for successful reproduction is dictated by the social environment, but we found no evidence that male offspring were developmentally suppressed in their natal social groups. Our findings suggest that puberty in male New World callitrichid primates occurs more quickly than puberty in Old World primates, even though both have similar patterns of development. PMID:11804940

  6. Puberty influences medial temporal lobe and cortical gray matter maturation differently in boys than girls matched for sexual maturity.

    PubMed

    Bramen, Jennifer E; Hranilovich, Jennifer A; Dahl, Ronald E; Forbes, Erika E; Chen, Jessica; Toga, Arthur W; Dinov, Ivo D; Worthman, Carol M; Sowell, Elizabeth R

    2011-03-01

    Sex differences in age- and puberty-related maturation of human brain structure have been observed in typically developing age-matched boys and girls. Because girls mature 1-2 years earlier than boys, the present study aimed at assessing sex differences in brain structure by studying 80 adolescent boys and girls matched on sexual maturity, rather than age. We evaluated pubertal influences on medial temporal lobe (MTL), thalamic, caudate, and cortical gray matter volumes utilizing structural magnetic resonance imaging and 2 measures of pubertal status: physical sexual maturity and circulating testosterone. As predicted, significant interactions between sex and the effect of puberty were observed in regions with high sex steroid hormone receptor densities; sex differences in the right hippocampus, bilateral amygdala, and cortical gray matter were greater in more sexually mature adolescents. Within sex, we found larger volumes in MTL structures in more sexually mature boys, whereas smaller volumes were observed in more sexually mature girls. Our results demonstrate puberty-related maturation of the hippocampus, amygdala, and cortical gray matter that is not confounded by age, and is different for girls and boys, which may contribute to differences in social and cognitive development during adolescence, and lasting sexual dimorphisms in the adult brain.

  7. Biology of the Sertoli Cell in the Fetal, Pubertal, and Adult Mammalian Testis.

    PubMed

    Chojnacka, Katarzyna; Zarzycka, Marta; Mruk, Dolores D

    2016-01-01

    A healthy man typically produces between 50 × 10(6) and 200 × 10(6) spermatozoa per day by spermatogenesis; in the absence of Sertoli cells in the male gonad, this individual would be infertile. In the adult testis, Sertoli cells are sustentacular cells that support germ cell development by secreting proteins and other important biomolecules that are essential for germ cell survival and maturation, establishing the blood-testis barrier, and facilitating spermatozoa detachment at spermiation. In the fetal testis, on the other hand, pre-Sertoli cells form the testis cords, the future seminiferous tubules. However, the role of pre-Sertoli cells in this process is much less clear than the function of Sertoli cells in the adult testis. Within this framework, we provide an overview of the biology of the fetal, pubertal, and adult Sertoli cell, highlighting relevant cell biology studies that have expanded our understanding of mammalian spermatogenesis. PMID:27300181

  8. Modeling Pubertal Timing and Tempo and Examining Links to Behavior Problems

    ERIC Educational Resources Information Center

    Beltz, Adriene M.; Corley, Robin P.; Bricker, Josh B.; Wadsworth, Sally J.; Berenbaum, Sheri A.

    2014-01-01

    Research on the role of puberty in adolescent psychological development requires attention to the meaning and measurement of pubertal development. Particular questions concern the utility of self-report, the need for complex models to describe pubertal development, the psychological significance of pubertal timing vs. tempo, and sex differences in…

  9. Rasburicase in the prevention of laboratory/clinical tumour lysis syndrome in children with advanced mature B-NHL: A Children’s Oncology Group Report

    PubMed Central

    Galardy, Paul; Hochberg, Jessica; Perkins, Sherrie L.; Harrison, Lauren; Goldman, Stanton; Cairo, Mitchell S.

    2013-01-01

    Summary Laboratory (LTLS) and clinical (CTLS) tumour lysis syndrome (TLS) are frequent complications in newly diagnosed children with advanced mature B cell non-Hodgkin lymphoma (B-NHL). Rasburicase, compared to allopurinol, results in more rapid reduction of uric acid in paediatric patients at risk for TLS. However, the safety and efficacy of rasburicase for the treatment or or prevention of TLS has not been prospectively evaluated. Children with newly diagnosed stage III–IV, bone marrow+ and/or central nervous system+ mature B-NHL received hydration and rasburicase prior to cytoreductive therapy. Rasburicase was safe and well-tolerated and there were no grade III–IV toxicities probably or directly related to rasburicase. Patients with an initial lactate dehydrogenase ≥2x upper limit of normal had a significantly elevated uric acid level (P=0.005), increased incidence of TLS (p-0.005) and lower glomerular filtration rate (GFR; p<0.001). Following rasburicase, there was only a 9% and 5% incidence of LTLS and CTLS, respectively. Furthermore, there was a significant improvement in estimated GFR from Day 0 to Day 7 following rasburicase (p=0.0007) and only 1.3% of patients required new onset renal assisted support after rasburicase administration. A TLS strategy incorporating rasburicase prior to cytoreductive chemotherapy proved safe and effective in preventing new onset renal failure and was associated with a significant improvement in GFR. PMID:24032600

  10. Adolescent Pubertal Status and Affective Family Relationships: A Multivariate Assessment.

    ERIC Educational Resources Information Center

    Papini, Dennis R.; Sebby, Richard A.

    1987-01-01

    Fifty-one families responded to questionnaires on affective relations between parents and their adolescent children. On the basis of the pubertal status of their children, families were classified into prepubertal, transpubertal, or postpubertal groups. Results showed that differences in family relationships were due to the transformation of…

  11. The role of environmental factors in pubertal gynecomastia

    EPA Science Inventory

    Proliferation of grandular tissue in the male breast during puberty, or pubertal gynecomastia, is a common condition that is usually benign and reversible. Since not all boys develop gynecomastia during puberty we were interested in whether environmental factors play a role. Furt...

  12. Sex steroids, growth hormone, leptin and the pubertal growth spurt.

    PubMed

    Rogol, Alan D

    2010-01-01

    A normal rate for the linear growth of a child or adolescent is a strong statement for the good general health of that child. Normal growth during childhood is primarily dependent on adequate nutrition, an adequate psychosocial environment, the absence of disease and adequate amounts thyroid hormone and growth hormone (and its downstream product, IGF-1). At adolescence there is the reawakening of the hypothalamic-pituitary-gonadal axis and its interaction with the GH/IGF-1 axis to subserve the pubertal growth spurt. The fat tissue-derived hormone, leptin and its receptor are likely involved in at least two aspects of pubertal development - sexual development itself and the alterations in body composition including the regional distribution of fat and bone mineralization. During the prepubertal years the male female differences in body composition are quite modest, but change remarkably during pubertal development with boys showing a relative decrement in fat percentage and girls a marked increase in concert with rising levels of circulating leptin. The boys show a much greater increase in lean body tissue and the relative proportions of water, muscle and bone. These may be observed as the differential growth of the shoulders and hips. The net effect of these pubertal changes is that the young adult woman has approximately 25% body fat in the 'gynoid' distribution while the male has much more muscle, especially in the shoulders and upper body but only approximately 13% body fat.

  13. Long-term consequences of pubertal timing for youth depression: Identifying personal and contextual pathways of risk

    PubMed Central

    RUDOLPH, KAREN D.; TROOP-GORDON, WENDY; LAMBERT, SHARON F.; NATSUAKI, MISAKI N.

    2015-01-01

    This research explored sex differences in the pathways linking pubertal timing to depression across 4 years. A sample of 167 youth (M age = 12.41 years, SD = 1.19) and their caregivers completed measures of puberty and semistructured interviews of interpersonal stress and youth depression. Youth reported on psychological (negative self-focus, anxious arousal) and social–behavioral (coping) characteristics; parents reported on youths’ social–behavioral characteristics (withdrawal/social problems) and deviant peer affiliations. Early maturation predicted stable high trajectories of depression in girls; although early maturing boys showed low initial levels of depression, they did not differ from girls by the final wave of the study. Latent growth curve analyses identified several psychological, social–behavioral, and interpersonal pathways accounting for the contribution of pubertal timing to initial and enduring risk for depression in girls as well as emerging risk for depression in boys. These findings provide novel insight into multilevel processes accounting for sex differences in depression across the adolescent transition. PMID:25422971

  14. Career Maturity.

    ERIC Educational Resources Information Center

    Crites, John O.

    1973-01-01

    Research in the field of Career Maturity is reviewed and summarized, with particular attention to Super's Career Pattern Study, Gribbons and Lohnes' Career Development Study, and Crites' Vocational Development Project. Crites' organization and revision into a hierarchical structure of the five dimensions of vocational maturity proposed in Supers'…

  15. Stress-induced progesterone secretion and progesterone receptor immunoreactivity in the paraventricular nucleus are modulated by pubertal development in male rats.

    PubMed

    Romeo, Russell D; Bellani, Rudy; McEwen, Bruce S

    2005-12-01

    Male rats show a differential adrenocortical response to stress before and after pubertal development, such that prepubertal animals have a more prolonged stress-induced corticosterone response compared to adults. Whether pubertal maturation affects other adrenocortical responses to stress is currently unknown. To address this question, we assessed stress-induced progesterone secretion in both intact and gonadectomized prepubertal (28 days of age) and adult (77 days of age) male rats either before or after exposure to a 30 min session of restraint stress. We found that prepubertal males show a greater and more prolonged stress-induced progesterone response compared to adults. We also found a similar effect in castrated prepubertal and adult males, indicating the differential stress-induced progesterone response is not gonadal in origin. We also examined progesterone receptor (PR) levels by immunohistochemistry in the paraventricular nucleus (PVN) of the hypothalamus, a key regulatory nucleus of the hypothalamic-pituitary-adrenal (HPA) axis, and found lower PR protein expression in the PVN of prepubertal compared to adult males. These data indicate that in addition to corticosterone, stress-induced adrenocortical progesterone levels are differentially affected by pubertal maturation. Furthermore, these data raise the possibility of different progesterone sensitivity of the PVN before and after puberty. The significance of this differential response is presently unknown. However, given the pleiotropic effects of progesterone on male physiology and behaviour, it is likely that the disparate post-stress exposure to progesterone affects the prepubertal and adult male differently.

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

    PubMed

    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. PMID:15305119

  17. Virus Maturation

    PubMed Central

    Veesler, David; Johnson, John E.

    2013-01-01

    We examined virus maturation of selected non-enveloped and enveloped ssRNA viruses; retroviruses; bacteriophages and herpes virus. Processes associated with maturation in the RNA viruses range from subtle (noda and picornaviruses) to dramatic (tetraviruses and togaviruses). The elaborate assembly and maturation pathway of HIV is discussed in contrast to the less sophisticated but highly efficient processes associated with togaviruses. Bacteriophage assembly and maturation are discussed in general terms with specific examples chosen for emphasis. Finally the herpes viruses are compared with bacteriophages. The data support divergent evolution of noda, picorna and tetraviruses from a common ancestor and divergent evolution of alpha and flaviviruses from a common ancestor. Likewise, bacteriophages and herpes viruses almost certainly share a common ancestor in their evolution. Comparing all the viruses, we conclude that maturation is a convergent process that is required to solve conflicting requirements in biological dynamics and function. PMID:22404678

  18. The effects of hydraulic resistance strength training in pre-pubertal males.

    PubMed

    Weltman, A; Janney, C; Rians, C B; Strand, K; Berg, B; Tippitt, S; Wise, J; Cahill, B R; Katch, F I

    1986-12-01

    In order to examine the effectiveness and safety of hydraulic resistance strength training in young males, 26 pre-pubertal males (mean age = 8.2 +/- 1.3 yr) completed a 14-wk strength training study. Subjects were evaluated before and after the 14-wk experimental period for pubertal state (Tanner's sexual maturity rating, serum testosterone, and serum dihydroepiandrosterone sulfate). Effectiveness of the strength training program was determined by measuring pre-post differences in: isokinetic strength for flexion and extension at the knee and elbow joints at two speeds (30 degrees and 90 degrees X s-1) (KIN COM, Chattecx, Inc., Chattanooga, TN), flexibility, standing long jump, vertical jump, body composition parameters, maximal oxygen consumption, and creatinine phosphokinase. Safety of strength training was assessed by biphasic musculoskeletal scintigraphy before and after the program and by physician evaluation of complaints by subjects. Strength training subjects (N = 16) participated in a 45 min/session, 3 session/wk, 14-wk supervised strength training program with an attendance rate of 91.5%. Participants performed concentric work using hydraulic resistance equipment (Hydra-Fitness Industries, Belton, TX). Eccentric work was not performed. Control subjects (N = 10) did not strength train but did participate in sport activities and activities of daily living. Results indicated that strength training subjects increased isokinetic strength as a result of strength training (average concentric work/repetition increases by 18.5 to 36.6% for the eight motions tested; torque scores over the first 90% of the range of motion increases by 13.1 to 45.1% for the eight motions tested). These changes were significantly greater than changes seen in the control group (P less than 0.05). Strength training subjects also demonstrated significant improvements (as compared to control subjects) in vertical jump (+10.4%), flexibility (+8.4%), and maximal oxygen consumption [+19

  19. Genetic determinants of prepubertal and pubertal growth and development.

    PubMed

    Thomis, Martine A; Towne, Bradford

    2006-12-01

    This article surveys the current general understanding of genetic influences on within- and between-population variation in growth and development in the context of establishing an International Growth Standard for Preadolescent and Adolescent Children. Traditional genetic epidemiologic analysis methods are reviewed, and evidence from family studies for genetic effects on different measures of growth and development is then presented. Findings from linkage and association studies seeking to identify specific genomic locations and allelic variants of genes influencing variation in growth and maturation are then summarized. Special mention is made of the need to study the interactions between genes and environments. At present, specific genes and polymorphisms contributing to variation in growth and maturation are only beginning to be identified. Larger genetic epidemiologic studies are needed in different parts of the world to better explore population differences in gene frequencies and gene-environment interactions. As advances continue to be made in molecular and statistical genetic methods, the genetic architecture of complex processes, including those of growth and development, will become better elucidated. For now, it can only be concluded that although the fundamental genetic underpinnings of the growth and development of children worldwide are likely to be essentially the same, there are also likely to be differences between populations in the frequencies of allelic gene variants that influence growth and maturation and in the nature of gene-environment interactions. This does not necessarily preclude an international growth reference, but it does have important implications for the form that such a reference might ultimately take.

  20. Pubertal development and behavior: hormonal activation of social and motivational tendencies.

    PubMed

    Forbes, Erika E; Dahl, Ronald E

    2010-02-01

    Adolescence is a time of dramatic changes including rapid physical growth, the onset of sexual maturation, the activation of new drives and motivations, and a wide array of social and affective changes and challenges. This review focuses on behavioral changes in this interval and is organized by the claim that a key set of these adolescent changes are part of a more general re-orientation of social behavior. More specifically we hypothesize that pubertal maturation is associated with the activation of social and motivational tendencies, which in turn influence behavior and emotion in adolescence depending upon interactions with social context. We focus on evidence for two examples of these motivational changes: (1) increases in sensation-seeking (motivational tendency to want to experience high-intensity, exciting experiences) and (2) stronger natural interest in--and pursuit of--contact with peers and potential romantic partners. We consider how these motivational changes contribute to the broader social re-orientation of adolescence, including exploration of social experiences, development of skills and knowledge relevant to taking on adult social roles, individuation from family, and establishment of an individual identity, all of which represent core developmental tasks during this period in the life span (Blakemore, 2008; Dahl & Spear, 2004; Steinberg & Morris, 2000). The paper also emphasizes the importance of investigating and understanding the direct influences of puberty on behavior and disentangling these from the broader set of changes during adolescent development.

  1. Chromosomes 6 and 13 harbor genes that regulate pubertal timing in mouse chromosome substitution strains.

    PubMed

    Krewson, Thomas D; Supelak, Pamela J; Hill, Annie E; Singer, Jonathan B; Lander, Eric S; Nadeau, Joseph H; Palmert, Mark R

    2004-10-01

    Variation in the onset of puberty among inbred strains of mice suggests that quantitative trait loci (QTLs) affect neurological and hormonal aspects of sexual maturation. Taking a novel approach toward identifying factors that regulate the hypothalamic-pituitary-gonadal (HPG) axis, we evaluated pubertal timing [as assessed by vaginal opening (VO)] in two inbred strains of mice, A/J and C57BL/6J (B6), and in a panel of chromosome substitution strains (CSSs) generated from A/J and B6 mice. In each CSS, a single chromosome from A/J has been substituted in a homozygous fashion for the corresponding chromosome in B6, partitioning the A/J genome into 22 strains with a common host (B6) background. VO occurred significantly earlier in A/J compared with B6 mice. Although the majority of the CSSs assessed had a timing of VO that was similar to the progenitor B6 strain, CSSs for chromosomes 6 and 13 each displayed significantly earlier time of VO than B6 mice. F1 (B6 x CSS) mice for chromosomes 6 and 13 displayed phenotypes that were intermediate between the CSS and B6 strains, suggesting that the trait was inherited in a codominant manner. These findings demonstrate that chromosomes 6 and 13 harbor QTLs that control the timing of VO. Identification of the responsible genes may reveal factors that regulate the maturation of the HPG axis and determine the timing of puberty.

  2. Maturation of the adolescent brain

    PubMed Central

    Arain, Mariam; Haque, Maliha; Johal, Lina; Mathur, Puja; Nel, Wynand; Rais, Afsha; Sandhu, Ranbir; Sharma, Sushil

    2013-01-01

    Adolescence is the developmental epoch during which children become adults – intellectually, physically, hormonally, and socially. Adolescence is a tumultuous time, full of changes and transformations. The pubertal transition to adulthood involves both gonadal and behavioral maturation. Magnetic resonance imaging studies have discovered that myelinogenesis, required for proper insulation and efficient neurocybernetics, continues from childhood and the brain’s region-specific neurocircuitry remains structurally and functionally vulnerable to impulsive sex, food, and sleep habits. The maturation of the adolescent brain is also influenced by heredity, environment, and sex hormones (estrogen, progesterone, and testosterone), which play a crucial role in myelination. Furthermore, glutamatergic neurotransmission predominates, whereas gamma-aminobutyric acid neurotransmission remains under construction, and this might be responsible for immature and impulsive behavior and neurobehavioral excitement during adolescent life. The adolescent population is highly vulnerable to driving under the influence of alcohol and social maladjustments due to an immature limbic system and prefrontal cortex. Synaptic plasticity and the release of neurotransmitters may also be influenced by environmental neurotoxins and drugs of abuse including cigarettes, caffeine, and alcohol during adolescence. Adolescents may become involved with offensive crimes, irresponsible behavior, unprotected sex, juvenile courts, or even prison. According to a report by the Centers for Disease Control and Prevention, the major cause of death among the teenage population is due to injury and violence related to sex and substance abuse. Prenatal neglect, cigarette smoking, and alcohol consumption may also significantly impact maturation of the adolescent brain. Pharmacological interventions to regulate adolescent behavior have been attempted with limited success. Since several factors, including age, sex

  3. Effects of Pubertal Exposure to Dietary Soy on Estrogen Receptor Activity in the Breast of Cynomolgus Macaques.

    PubMed

    Dewi, Fitriya N; Wood, Charles E; Willson, Cynthia J; Register, Thomas C; Lees, Cynthia J; Howard, Timothy D; Huang, Zhiqing; Murphy, Susan K; Tooze, Janet A; Chou, Jeff W; Miller, Lance D; Cline, J Mark

    2016-05-01

    Endogenous estrogens influence mammary gland development during puberty and breast cancer risk during adulthood. Early-life exposure to dietary or environmental estrogens may alter estrogen-mediated processes. Soy foods contain phytoestrogenic isoflavones (IF), which have mixed estrogen agonist/antagonist properties. Here, we evaluated mammary gland responses over time in pubertal female cynomolgus macaques fed diets containing either casein/lactalbumin (n = 12) or soy protein containing a human-equivalent dose of 120 mg IF/day (n = 17) for approximately 4.5 years spanning menarche. We assessed estrogen receptor (ER) expression and activity, promoter methylation of ERs and their downstream targets, and markers of estrogen metabolism. Expression of ERα and classical ERα response genes (TFF1, PGR, and GREB1) decreased with maturity, independent of diet. A significant inverse correlation was observed between TFF1 mRNA and methylation of CpG sites within the TFF1 promoter. Soy effects included lower ERβ expression before menarche and lower mRNA for ERα and GREB1 after menarche. Expression of GATA-3, an epithelial differentiation marker that regulates ERα-mediated transcription, was elevated before menarche and decreased after menarche in soy-fed animals. Soy did not significantly alter expression of other ER activity markers, estrogen-metabolizing enzymes, or promoter methylation for ERs or ER-regulated genes. Our results demonstrate greater ER expression and activity during the pubertal transition, supporting the idea that this life stage is a critical window for phenotypic modulation by estrogenic compounds. Pubertal soy exposure decreases mammary ERα expression after menarche and exerts subtle effects on receptor activity and mammary gland differentiation. Cancer Prev Res; 9(5); 385-95. ©2016 AACR.

  4. Prepubertal and pubertal canine reproductive studies: conflicting aspects.

    PubMed

    Gobello, C

    2014-12-01

    Insufficient knowledge has been acquired regarding the prepubertal and pubertal periods of domestic canids. Until further information becomes available, a better standardization of the definitions, a careful and complete description of experimental variables and end points is necessary to diminish experimental bias in published trials. The aim of this report is therefore to discuss the definition of puberty and some of the most conflicting conditions influencing the pubertal transition (e.g. age and body weight and condition score among others) that, in turn, will be useful for the future design of reproductive studies on the domestic dog. Only trials that could be easily processed by a meta-analysis will contribute to an improvement of our general knowledge on the reproductive physiology of this particular species. PMID:25251604

  5. Pubertal Development in Mexican American Girls: The Family’s Perspective

    PubMed Central

    Jean, Rosenie Thelus; Bondy, Melissa L.; Wilkinson, Anna V.; Forman, Michele R.

    2011-01-01

    Mexican American (MA) girls are entering puberty earlier than in the past, yet few studies have explored the perceptions surrounding puberty among this group. We conducted separate focus groups for fathers, mothers, and daughters aged 6 to 12 years to explore perceptions of body image, pubertal development, communications, and sources of puberty-related information in MA participants. Our results revealed parental concerns about daughters’ weight and pubertal development, as well as differences in their communication with their daughters. Although both parents willingly discussed pubertal issues concerning their daughters, mothers had a more active role in conveying pubertal information to daughters. Among the girls, there was a gap in knowledge about the pubertal process between the younger and older girls. Our findings present opportunities and challenges for addressing obesity as a pubertal risk factor in MA girls; however, more studies are needed to understand family beliefs and sociocultural dynamics surrounding puberty in MAs. PMID:19690203

  6. Pubertal Stage and Deliberate Self-Harm in Adolescents

    ERIC Educational Resources Information Center

    Patton, George C.; Hemphill, Sheryl A.; Beyers, Jennifer M.; Bond, Lyndal; Toumbourou, John W.; McMorris, Barbara J.; Catalano, Richard F.

    2007-01-01

    Objective: To ascertain the association between pubertal stage and deliberate self-harm. Method: Cross-sectional survey of 12- to 15-year-olds in 300 secondary schools in the U.S. state of Washington in February-April 2002 and the Australian state of Victoria in June-August 2002. A total of 3,332 students in grades 7 and 9 provided complete data…

  7. DNA Methylation Patterns in the Hypothalamus of Female Pubertal Goats

    PubMed Central

    Li, Xiumei; Gao, Xiaoxiao; Zhang, Kaifa; Luo, Lei; Ding, Jianping; Zhang, Yunhai; Li, Yunsheng; Cao, Hongguo; Ling, Yinghui; Zhang, Xiaorong; Liu, Ya; Fang, Fugui

    2016-01-01

    Female pubertal development is tightly controlled by complex mechanisms, including neuroendocrine and epigenetic regulatory pathways. Specific gene expression patterns can be influenced by DNA methylation changes in the hypothalamus, which can in turn regulate timing of puberty onset. In order to understand the relationship between DNA methylation changes and gene expression patterns in the hypothalamus of pubertal goats, whole-genome bisulfite sequencing and RNA-sequencing analyses were carried out. There was a decline in DNA methylation levels in the hypothalamus during puberty and 268 differentially methylated regions (DMR) in the genome, with differential patterns in different gene regions. There were 1049 genes identified with distinct expression patterns. High levels of DNA methylation were detected in promoters, introns and 3′-untranslated regions (UTRs). Levels of methylation decreased gradually from promoters to 5′-UTRs and increased from 5′-UTRs to introns. Methylation density analysis demonstrated that methylation level variation was consistent with the density in the promoter, exon, intron, 5′-UTRs and 3′-UTRs. Analyses of CpG island (CGI) sites showed that the enriched gene contents were gene bodies, intergenic regions and introns, and these CGI sites were hypermethylated. Our study demonstrated that DNA methylation changes may influence gene expression profiles in the hypothalamus of goats during the onset of puberty, which may provide new insights into the mechanisms involved in pubertal onset. PMID:27788248

  8. Treatment Effects of Removable Functional Appliances in Pre-Pubertal and Pubertal Class II Patients: A Systematic Review and Meta-Analysis of Controlled Studies

    PubMed Central

    Perinetti, Giuseppe; Primožič, Jasmina; Franchi, Lorenzo; Contardo, Luca

    2015-01-01

    Background Treatment effects of removable functional appliances in Class II malocclusion patients according to the pre-pubertal or pubertal growth phase has yet to be clarified. Objectives To assess and compare skeletal and dentoalveolar effects of removable functional appliances in Class II malocclusion treatment between pre-pubertal and pubertal patients. Search methods Literature survey using the Medline, SCOPUS, LILACS and SciELO databases, the Cochrane Library from inception to May 31, 2015. A manual search was also performed. Selection criteria Randomised (RCTs) or controlled clinical trials with a matched untreated control group. No restrictions were set regarding the type of removable appliance whenever used alone. Data collection and analysis For the meta-analysis, cephalometric parameters on the supplementary mandibular growth were the main outcomes, with other cephalometric parameters considered as secondary outcomes. Risk of bias in individual and across studies were evaluated along with sensitivity analysis for low quality studies. Mean differences and 95% confidence intervals for annualised changes were computed according to a random model. Differences between pre-pubertal and pubertal patients were assessed by subgroup analyses. GRADE assessment was performed for the main outcomes. Results Twelve articles (but only 3 RCTs) were included accounting for 8 pre-pubertal and 7 pubertal groups. Overall supplementary total mandibular length and mandibular ramus height were 0.95 mm (0.38, 1.51) and 0.00 mm (-0.52, 0.53) for pre-pubertal patients and 2.91 mm (2.04, 3.79) and 2.18 mm (1.51, 2.86) for pubertal patients, respectively. The subgroup difference was significant for both parameters (p<0.001). No maxillary growth restrain or increase in facial divergence was seen in either subgroup. The GRADE assessment was low for the pre-pubertal patients, and generally moderate for the pubertal patients. Conclusions Taking into account the limited quality and

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

    PubMed

    Almstrup, Kristian; Lindhardt Johansen, Marie; Busch, Alexander S; Hagen, Casper P; Nielsen, John E; Petersen, Jørgen Holm; Juul, Anders

    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 polymorphisms only 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 the promoter of TRIP6 was co-ordinately regulated as a function of pubertal development. In accordance, immunohistochemistry identified TRIP6 in adult, but not pre-pubertal, testicular Leydig cells and circulating TRIP6 levels doubled during puberty. Using elastic net prediction models, methylation patterns predicted pubertal development more accurately than chronological age. We demonstrate for the first time that pubertal attainment of secondary sexual characteristics is mirrored by changes in DNA methylation patterns in peripheral blood. Thus, modulations of the epigenome seem involved in regulation of the individual pubertal timing.

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

    PubMed Central

    Almstrup, Kristian; Lindhardt Johansen, Marie; Busch, Alexander S.; Hagen, Casper P.; Nielsen, John E.; Petersen, Jørgen Holm; Juul, Anders

    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 polymorphisms only 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 the promoter of TRIP6 was co-ordinately regulated as a function of pubertal development. In accordance, immunohistochemistry identified TRIP6 in adult, but not pre-pubertal, testicular Leydig cells and circulating TRIP6 levels doubled during puberty. Using elastic net prediction models, methylation patterns predicted pubertal development more accurately than chronological age. We demonstrate for the first time that pubertal attainment of secondary sexual characteristics is mirrored by changes in DNA methylation patterns in peripheral blood. Thus, modulations of the epigenome seem involved in regulation of the individual pubertal timing. PMID:27349168

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

    PubMed

    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. PMID:19144220

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

    PubMed

    Almstrup, Kristian; Lindhardt Johansen, Marie; Busch, Alexander S; Hagen, Casper P; Nielsen, John E; Petersen, Jørgen Holm; Juul, Anders

    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 polymorphisms only 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 the promoter of TRIP6 was co-ordinately regulated as a function of pubertal development. In accordance, immunohistochemistry identified TRIP6 in adult, but not pre-pubertal, testicular Leydig cells and circulating TRIP6 levels doubled during puberty. Using elastic net prediction models, methylation patterns predicted pubertal development more accurately than chronological age. We demonstrate for the first time that pubertal attainment of secondary sexual characteristics is mirrored by changes in DNA methylation patterns in peripheral blood. Thus, modulations of the epigenome seem involved in regulation of the individual pubertal timing. PMID:27349168

  13. The ultrasound appearance of the patellar tendon attachment to the tibia in young athletes is conditional on gender and pubertal stage.

    PubMed

    Ducher, Gaele; Cook, Jill; Lammers, Greg; Coombs, Peter; Ptazsnik, Ron; Black, Jeni; Bass, Shona L

    2010-01-01

    This cross-sectional study investigated the imaging appearance of the patellar tendon attachment to the tibia in young male and female tennis players of different ages and pubertal status. Forty-four competitive young players, who had been playing tennis at least for 2 years, were recruited from a tennis school and local tennis clubs. All subjects had bilateral ultrasound imaging of the patellar tendon attachment to the tibia. Standard anthropometric measurements, pubertal status and injury history were recorded. Ultrasound appearance of the patellar tendon attachment was categorised into three stages: cartilage attachment, insertional cartilage and mature attachment. Cartilage attachment was more prevalent in boys (32%) and extended further into puberty (until Tanner stage 4) compared to girls (6% and Tanner stage 1). Tendons with Osgood-Schlatter Disease symptoms (n=3) did not have a cartilage attachment. Imaging appearance commonly seen in young active athletes, consistent with a clinical diagnosis of OSD, was more common in boys and in the pre- and peri-pubertal stages.

  14. A longitudinal study: changes in cortical thickness and surface area during pubertal maturation.

    PubMed

    Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Dahl, Ronald E; Sowell, Elizabeth R

    2015-01-01

    Sex hormones have been shown to contribute to the organization and function of the brain during puberty and adolescence. Moreover, it has been suggested that distinct hormone changes in girls versus boys may contribute to the emergence of sex differences in internalizing and externalizing behavior during adolescence. In the current longitudinal study, the influence of within-subject changes in puberty (physical and hormonal) on cortical thickness and surface area was examined across a 2-year span, while controlling for age. Greater increases in Tanner Stage predicted less superior frontal thinning and decreases in precuneus surface area in both sexes. Significant Tanner Stage and sex interactions were also seen, with less right superior temporal thinning in girls but not boys, as well as greater decreases in the right bank of the superior temporal sulcus surface area in boys compared to girls. In addition, within-subject changes in testosterone over the 2-year follow-up period were found to relate to decreases in middle superior frontal surface area in boys, but increases in surface area in girls. Lastly, larger increases in estradiol in girls predicted greater middle temporal lobe thinning. These results show that within-subject physical and hormonal markers of puberty relate to region and sex-specific changes in cortical development across adolescence. PMID:25793383

  15. The Effect of Exposure to Atrazine on Dopaminergic Development in Pubertal Male SD Rats.

    PubMed

    Li, Yan-Shu; He, Xi; Ma, Kun; Wu, Yan-Ping; Li, Bai-Xiang

    2015-10-01

    Atrazine (ATR, 2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is used worldwide as a herbicide, and its presence in the environment has resulted in documented human exposure. A lack of strong evidence for genetic heritability of idiopathic Parkinson's disease has focused attention on environmental toxicants in the disease etiology, particularly agrichemicals. Parkinson's disease is associated with advanced age and is characterized by the degeneration of dopaminergic neurons, but it is unclear whether specific neuronal damage could result from insults during development. The juvenile period is particularly vulnerable to environmental agent, therefore, we evaluated the effects of a 28-day exposure to ATR on the dopaminergic system in pubertal rats. Sprague-Dawley rats were treated orally with ATR at 50, 100, and 200 mg/kg bw, daily from postnatal days 27 to 54. In this study, we examined the hypothesis that pubertal exposure to ATR would disrupt the development of the nigrostriatal dopamine (DA) system. The content of DA and levodopa (L-DA) were examined in striatum samples by HPLC-FL, and the mRNA and protein expression of tyrosine hydroxylase, orphan nuclear hormone receptor (Nurr1), Nurr1 interacting protein (NuIP), and cyclin-dependent kinase inhibitors of the Cip̲Kip family (p57kip2) were examined in samples of the nigrostriatum by use of fluorescence Real-Time quantitative polymerase chain reaction (PCR). Exposure of juvenile rats to the high dose of ATR led to reduced levels of DA and L-DA, genes expression of NuIP, Nurr1, and p57kip2 in animals. PMID:26331294

  16. The Effect of Exposure to Atrazine on Dopaminergic Development in Pubertal Male SD Rats.

    PubMed

    Li, Yan-Shu; He, Xi; Ma, Kun; Wu, Yan-Ping; Li, Bai-Xiang

    2015-10-01

    Atrazine (ATR, 2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is used worldwide as a herbicide, and its presence in the environment has resulted in documented human exposure. A lack of strong evidence for genetic heritability of idiopathic Parkinson's disease has focused attention on environmental toxicants in the disease etiology, particularly agrichemicals. Parkinson's disease is associated with advanced age and is characterized by the degeneration of dopaminergic neurons, but it is unclear whether specific neuronal damage could result from insults during development. The juvenile period is particularly vulnerable to environmental agent, therefore, we evaluated the effects of a 28-day exposure to ATR on the dopaminergic system in pubertal rats. Sprague-Dawley rats were treated orally with ATR at 50, 100, and 200 mg/kg bw, daily from postnatal days 27 to 54. In this study, we examined the hypothesis that pubertal exposure to ATR would disrupt the development of the nigrostriatal dopamine (DA) system. The content of DA and levodopa (L-DA) were examined in striatum samples by HPLC-FL, and the mRNA and protein expression of tyrosine hydroxylase, orphan nuclear hormone receptor (Nurr1), Nurr1 interacting protein (NuIP), and cyclin-dependent kinase inhibitors of the Cip̲Kip family (p57kip2) were examined in samples of the nigrostriatum by use of fluorescence Real-Time quantitative polymerase chain reaction (PCR). Exposure of juvenile rats to the high dose of ATR led to reduced levels of DA and L-DA, genes expression of NuIP, Nurr1, and p57kip2 in animals.

  17. In pubertal girls, naloxone fails to reverse the suppression of luteinizing hormone secretion by estradiol.

    PubMed

    Cemeroglu, A P; Kletter, G B; Guo, W; Brown, M B; Kelch, R P; Marshall, J C; Padmanabhan, V; Foster, C M

    1998-10-01

    Estradiol (E2) negative feedback on LH secretion was examined in 10 pubertal girls, testing the hypothesis that E2 suppresses LH pulse frequency and amplitude through opioid pathways. At 1000 h, a 32-h saline infusion was given, followed 1 week later by an E2 infusion at 13.8 nmol/m2 x h. During both infusions, four iv boluses of saline were given hourly beginning at 1200 h, and four naloxone iv boluses (0.1 mg/kg each) were given hourly beginning at 1200 h on the following day. Blood was obtained every 15 min for LH determination and every 60 min for E2 determination from 1200 h to the end of the infusion. E2 infusion increased the mean serum E2 concentration from 44+/-17 to 112+/-26 pmol/L (P < 0.01). The mean LH concentration between 2200-1200 h decreased from 3.19+/-0.89 to 1.99+/-0.65 IU/L (P = 0.014), and LH pulse amplitude decreased from 3.4+/-0.6 to 2.6+/-0.5 IU/L (P = 0.0076). Although there were 1.2 fewer pulses during E2 infusion compared to saline infusion, differences did not reach significance (P = 0.1; 95% confidence interval for the difference, -3.5, 1.1). Pituitary responsiveness to GnRH, assessed at the end of the infusion by administering 250 ng/kg GnRH iv, did not change during E2 infusion. The effect of naloxone blockade of opioid activity on LH secretion was determined by assessing the area under the curve (AUC) from 1200-1600 h. During saline infusion, the LH AUC was 1122+/-375 IU/L during saline boluses and 1575+/-403 IU/L during naloxone boluses (P = 0.39). When E2 was infused, the LH AUCs during saline and naloxone boluses were 865+/-249 and 866+/-250 IU/L, respectively. Thus, in pubertal girls: 1) E2 decreases the LH concentration and LH pulse amplitude; 2) the main site of negative feedback effect of E2 appears to be at the level of the hypothalamus; 3) an increase in LH secretion after naloxone administration could not be demonstrated in these girls and may depend on the maturity of the hypothalamic-pituitary-gonadal axis; and 4) opioid

  18. Negotiating the Early Developing Body: Pubertal Timing, Body Weight, and Adolescent Girls' Substance Use

    ERIC Educational Resources Information Center

    Tanner-Smith, Emily E.

    2010-01-01

    Despite knowledge that early pubertal timing predicts adolescent girls' substance use, it is still unclear whether this relationship persists beyond early adolescence and whether it is conditional on girls' body weight. This study examined the moderating role of body weight in the association between early pubertal timing and adolescent girls'…

  19. Pubertal Timing and Substance Use in Middle Adolescence: A 2-Year Follow-Up Study

    ERIC Educational Resources Information Center

    Kaltiala-Heino, Riittakerttu; Koivisto, Anna-Maija; Marttunen, Mauri; Frojd, Sari

    2011-01-01

    Earlier research has associated early puberty with emotional and behavioral symptoms particularly among girls, while among boys, findings have been contradictory as to whether risks are associated with early or late pubertal timing. We studied the association between pubertal timing and substance use behaviors in middle adolescence in a 2-year…

  20. Ethnicity, Perceived Pubertal Timing, Externalizing Behaviors, and Depressive Symptoms among Black Adolescent Girls

    ERIC Educational Resources Information Center

    Carter, Rona; Caldwell, Cleopatra Howard; Matusko, Niki; Antonucci, Toni; Jackson, James S.

    2011-01-01

    An accumulation of research evidence suggests that early pubertal timing plays a significant role in girls' behavioral and emotional problems. If early pubertal timing is a problematic event, then early developing Black girls should manifest evidence of this crisis because they tend to be the earliest to develop compared to other girls from…

  1. The Relationship between Pubertal Timing and Delinquent Behavior in Maltreated Male and Female Adolescents

    ERIC Educational Resources Information Center

    Negriff, Sonya; Trickett, Penelope K.

    2010-01-01

    This study examined the relationship between pubertal timing and delinquent behavior across two time points in a sample of 303 maltreated and 151 comparison adolescents aged between 9 and 13 years at enrollment. The first aim was to examine the relationship between pubertal timing and delinquency for the total sample and then to test for gender…

  2. A Longitudinal Investigation of Associations between Boys' Pubertal Timing and Adult Behavioral Health and Well-Being

    ERIC Educational Resources Information Center

    Taga, Keiko A.; Markey, Charlotte N.; Friedman, Howard S.

    2006-01-01

    To extend research linking pubertal timing and adolescent health outcomes, this study examines boys' pubertal timing and subsequent interpersonal success and health behaviors in mid adulthood. Past research has shown that boys' pubertal timing is associated with both positive and negative developmental outcomes in the short term, and so it is…

  3. Guidelines for pubertal suspension and gender reassignment for transgender adolescents.

    PubMed

    Hembree, Wylie C

    2011-10-01

    Pubertal suppression at Tanner stage 2 should be considered in adolescents with persistent gender identity disorder (GID). Issues related to achievement of adult height, timing of initiating sex steroid treatment, future fertility options, preventing uterine bleeding, and required modifications of genital surgery remain concerns. Concerns have been raised about altering neuropsychological development during cessation of puberty and reinitiation of puberty by the sex steroid opposite those determined by genetic sex. Collaborative assessment and treatment of dysphoric adolescents with persistent GID resolves these concerns and deepens our understanding of gender development.

  4. Pubertal impairment in Nhlh2 null mice is associated with hypothalamic and pituitary deficiencies.

    PubMed

    Cogliati, Tiziana; Delgado-Romero, Petra; Norwitz, Errol R; Guduric-Fuchs, Jasenka; Kaiser, Ursula B; Wray, Susan; Kirsch, Ilan R

    2007-12-01

    Pubertal development is impaired in mice lacking the basic helix-loop-helix transcription factor Nhlh2. The mechanisms underlying changes in reproduction in Nhlh2-deficient mice (Nhlh2(-/-)) are unclear. Here we show that hypothalamic GnRH-1 content is reduced in adult Nhlh2(-/-) mice as is the number of GnRH-1 neurons localized to mid- and caudal hypothalamic regions. This reduction was detected postnatally after normal migration of GnRH-1 neurons within nasal regions had occurred. Phenotype rescue experiments showed that female Nhlh2(-/-) mice were responsive to estrogen treatment. In contrast, puberty could not be primed in female Nhlh2(-/-) mice with a GnRH-1 regimen. The adenohypophysis of Nhlh2(-/-) mice was hypoplastic although it contained a full complement of the five anterior pituitary cell types. GnRH-1 receptors (GnRHRs) were reduced in Nhlh2(-/-) pituitary gonadotropes as compared with wild type. In vitro assays indicated that Nhlh2 expression is regulated in parallel with GnRHR expression. However, direct transcriptional activity of Nhlh2 on the GnRHR promoter was not found. These results indicate that Nhlh2 plays a role in the development and functional maintenance of the hypothalamic-pituitary-gonadal axis at least at two levels: 1) in the hypothalamus by regulating the number and distribution of GnRH-1 neurons and, 2) in the developing and mature adenohypophysis.

  5. Sequence variation in mature microRNA-608 and benefit from neo-adjuvant treatment in locally advanced rectal cancer patients.

    PubMed

    Sclafani, Francesco; Chau, Ian; Cunningham, David; Lampis, Andrea; Hahne, Jens Claus; Ghidini, Michele; Lote, Hazel; Zito, Domenico; Tabernero, Josep; Glimelius, Bengt; Cervantes, Andres; Begum, Ruwaida; De Castro, David Gonzalez; Wilson, Sanna Hulkki; Peckitt, Clare; Eltahir, Zakaria; Wotherspoon, Andrew; Tait, Diana; Brown, Gina; Oates, Jacqueline; Braconi, Chiara; Valeri, Nicola

    2016-09-01

    Single nucleotide polymorphisms (SNPs) in microRNA genes have been associated with colorectal cancer (CRC) risk, survival and response to treatment. Conflicting results are available on the association between rs4919510, a SNP in mature miR-608 and clinical outcome in CRC. Here, we analyzed the association between rs4919510 and benefit from perioperative treatment in a randomised phase II trial of neoadjuvant Capecitabine and Oxaliplatin (CAPOX) followed by chemo-radiotherapy, surgery and adjuvant CAPOX ± Cetuximab in high-risk locally advanced rectal cancer (LARC). A total of 155/164 (94.5%) patients were assessable. 95 (61.3%) were homozygous for CC, 55 (35.5%) heterozygous (CG) and 5 (3.2%) homozygous for GG. Median follow-up was 64.9 months. In the CAPOX arm the 5-year progression-free survival (PFS) and overall survival (OS) rates were 54.6% and 60.7% for CC and 82.0% and 82.1% for CG/GG, respectively (HR PFS 0.13, 95% CI: 0.12-0.83, P = 0.02; HR OS 0.38, 95% CI: 0.14-1.01, P = 0.05). In the CAPOX-C arm PFS and OS were 73.2 and 82.2%, respectively for CC carriers and 64.6 and 73.1% for CG/GG carriers (HR PFS 1.38, 95% CI: 0.61-3.13, P = 0.44; HR OS 1.34, 95% CI: 0.52-3.48, P = 0.55). An interaction was found between study treatment and rs4919510 genotype for both PFS (P = 0.02) and OS (P = 0.07). This is the first study investigating rs4919510 in LARC. The CC genotype appeared to be associated with worse prognosis compared to the CG/GG genotype in patients treated with chemotherapy and chemo-radiotherapy alone. Addition of Cetuximab to chemotherapy and chemo-radiotherapy in CC carriers appeared to improve clinical outcome. PMID:27381831

  6. Sequence variation in mature microRNA-608 and benefit from neo-adjuvant treatment in locally advanced rectal cancer patients

    PubMed Central

    Sclafani, Francesco; Chau, Ian; Cunningham, David; Lampis, Andrea; Hahne, Jens Claus; Ghidini, Michele; Lote, Hazel; Zito, Domenico; Tabernero, Josep; Glimelius, Bengt; Cervantes, Andres; Begum, Ruwaida; De Castro, David Gonzalez; Wilson, Sanna Hulkki; Peckitt, Clare; Eltahir, Zakaria; Wotherspoon, Andrew; Tait, Diana; Brown, Gina; Oates, Jacqueline; Braconi, Chiara; Valeri, Nicola

    2016-01-01

    Single nucleotide polymorphisms (SNPs) in microRNA genes have been associated with colorectal cancer (CRC) risk, survival and response to treatment. Conflicting results are available on the association between rs4919510, a SNP in mature miR-608 and clinical outcome in CRC. Here, we analyzed the association between rs4919510 and benefit from perioperative treatment in a randomised phase II trial of neoadjuvant Capecitabine and Oxaliplatin (CAPOX) followed by chemo-radiotherapy, surgery and adjuvant CAPOX ± Cetuximab in high-risk locally advanced rectal cancer (LARC). A total of 155/164 (94.5%) patients were assessable. 95 (61.3%) were homozygous for CC, 55 (35.5%) heterozygous (CG) and 5 (3.2%) homozygous for GG. Median follow-up was 64.9 months. In the CAPOX arm the 5-year progression-free survival (PFS) and overall survival (OS) rates were 54.6% and 60.7% for CC and 82.0% and 82.1% for CG/GG, respectively (HR PFS 0.13, 95% CI: 0.12–0.83, P = 0.02; HR OS 0.38, 95% CI: 0.14–1.01, P = 0.05). In the CAPOX-C arm PFS and OS were 73.2 and 82.2%, respectively for CC carriers and 64.6 and 73.1% for CG/GG carriers (HR PFS 1.38, 95% CI: 0.61–3.13, P = 0.44; HR OS 1.34, 95% CI: 0.52–3.48, P = 0.55). An interaction was found between study treatment and rs4919510 genotype for both PFS (P = 0.02) and OS (P = 0.07). This is the first study investigating rs4919510 in LARC. The CC genotype appeared to be associated with worse prognosis compared to the CG/GG genotype in patients treated with chemotherapy and chemo-radiotherapy alone. Addition of Cetuximab to chemotherapy and chemo-radiotherapy in CC carriers appeared to improve clinical outcome. PMID:27381831

  7. Market maturity

    SciTech Connect

    Meade, B.; Bowden, S.; Ellis, M

    1995-02-01

    The power sector in the Philipines provides one of the most mature independent power markets in Asia. Over the past five years, National Power Corp. (NPC), the government owned utility, has actively invited the power sector into power generation. Distribution has remained in the hands of private and rural cooperative utilities. Private utilities have been operating as full requirements customers of NPC while the growth in capacity additions by independent power producers (IPPs) has outpaced NPC`s for the second year in a row. With a recovering economy and regulatory reform proceeding, the outlook for independent power remains strong through the end of the decade. The Philipine Congress is now reviewing draft legislation that will decentralize NPC and begin the process of privatization and market-based reforms throughout the country`s power sector.

  8. Pubertal Onset in HIV-infected Children in the Era of Combination Antiretroviral Treatment

    PubMed Central

    WILLIAMS, Paige L.; ABZUG, Mark J.; JACOBSON, Denise L.; WANG, Jiajia; VAN DYKE, Russell B.; HAZRA, Rohan; PATEL, Kunjal; DIMEGLIO, Linda A.; MCFARLAND, Elizabeth J.; SILIO, Margarita; BORKOWSKY, William; SEAGE, George R.; OLESKE, James M.; GEFFNER, Mitchell E.

    2014-01-01

    Objective To evaluate associations of perinatal HIV infection (PHIV), HIV disease severity, and combination antiretroviral treatment with age at pubertal onset. Design Analysis of data from two U.S. longitudinal cohort studies [IMPAACT 219C and PHACS AMP], conducted 2000–2012, including PHIV and HIV-exposed uninfected (HEU) youth. Tanner stage assessments of pubertal status (breast and pubic hair in girls; genitalia and pubic hair in boys) were conducted annually. Methods We compared the timing of pubertal onset (Tanner stage ≥2) between PHIV and HEU youth using interval-censored models. For PHIV youth, we evaluated associations of HIV disease severity and combination antiretroviral treatment with age at pubertal onset, adjusting for race/ethnicity and birth cohort. Results The mean age at pubertal onset was significantly later for the 2086 PHIV youth compared to 453 HEU children (10.3 vs 9.6, 10.5 vs 10.0, 11.3 vs 10.4, and 11.5 vs 10.7 years according to female breast, female pubic hair, male genitalia, and male pubic hair staging, respectively, all p<0.001). PHIV youth with HIV-1 RNA viral load >10,000 copies/mL (vs ≤10,000 copies/mL) or CD4% <15% (vs ≥15%) had significantly later pubertal onset (by 4–13 months). Each additional year of combination antiretroviral treatment was associated with a 0.6- to1.2-month earlier mean age at pubertal onset, but this trend did not persist after adjustment for birth cohort. Conclusions Pubertal onset occurs significantly later in PHIV than in HEU youth, especially among those with more severe HIV disease. However, in the current era, combination antiretroviral treatment may result in more normal timing of pubertal onset. PMID:24145244

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

    PubMed

    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.

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

    PubMed

    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. PMID:26051297

  11. Role of intensive training in the growth and maturation of artistic gymnasts.

    PubMed

    Malina, Robert M; Baxter-Jones, Adam D G; Armstrong, Neil; Beunen, Gaston P; Caine, Dennis; Daly, Robin M; Lewis, Richard D; Rogol, Alan D; Russell, Keith

    2013-09-01

    Short stature and later maturation of youth artistic gymnasts are often attributed to the effects of intensive training from a young age. Given limitations of available data, inadequate specification of training, failure to consider other factors affecting growth and maturation, and failure to address epidemiological criteria for causality, it has not been possible thus far to establish cause-effect relationships between training and the growth and maturation of young artistic gymnasts. In response to this ongoing debate, the Scientific Commission of the International Gymnastics Federation (FIG) convened a committee to review the current literature and address four questions: (1) Is there a negative effect of training on attained adult stature? (2) Is there a negative effect of training on growth of body segments? (3) Does training attenuate pubertal growth and maturation, specifically, the rate of growth and/or the timing and tempo of maturation? (4) Does training negatively influence the endocrine system, specifically hormones related to growth and pubertal maturation? The basic information for the review was derived from the active involvement of committee members in research on normal variation and clinical aspects of growth and maturation, and on the growth and maturation of artistic gymnasts and other youth athletes. The committee was thus thoroughly familiar with the literature on growth and maturation in general and of gymnasts and young athletes. Relevant data were more available for females than males. Youth who persisted in the sport were a highly select sample, who tended to be shorter for chronological age but who had appropriate weight-for-height. Data for secondary sex characteristics, skeletal age and age at peak height velocity indicated later maturation, but the maturity status of gymnasts overlapped the normal range of variability observed in the general population. Gymnasts as a group demonstrated a pattern of growth and maturation similar to

  12. The Effects of Simazine, a Chlorotriazine Herbicide, on Female Pubertal Development*

    EPA Science Inventory

    Chlorotriazine herbicides, such as atrazine and its metabolites, have been shown to target the neuroendocrine regulation of male and female reproductive development. However, no studies have evaluated the effects of the chlorotriazine simazine on pubertal development in the femal...

  13. Dioxin and Polychlorinated Biphenyl Concentrations in Mother's Serum and the Timing of Pubertal Onset in Sons

    PubMed Central

    Humblet, Olivier; Williams, Paige L.; Korrick, Susan A.; Sergeyev, Oleg; Emond, Claude; Birnbaum, Linda S.; Burns, Jane S.; Altshul, Larisa; Patterson, Donald G.; Turner, Wayman E.; Lee, Mary M.; Revich, Boris; Hauser, Russ

    2013-01-01

    Background Animal studies have demonstrated that timing of pubertal onset can be altered by prenatal exposure to dioxins or polychlorinated biphenyls (PCBs), but studies of human populations have been quite limited. Methods We assessed the association between maternal serum concentrations of dioxins and PCBs and the sons’ age of pubertal onset in a prospective cohort of 489 mother–son pairs from Chapaevsk, Russia, a town contaminated with these chemicals during past industrial activity. The boys were recruited at ages 8 to 9 years, and 4 years of annual follow-up data were included in the analysis. Serum samples were collected at enrollment from both mothers and sons for measurement of dioxin and PCB concentrations using high-resolution mass spectrometry. The sons’ pubertal onset—defined as pubertal stage 2 or higher for genitalia (G) or pubic hair (P), or testicular volume >3 mL—was assessed annually by the same physician. Results In multivariate Cox models, elevated maternal serum PCBs were associated with earlier pubertal onset defined by stage G2 or higher (4th quartile hazard ratio = 1.7 [95% confidence interval = 1.1– 2.5]), but not for stage P2 or higher or for testicular volume >3 mL. Maternal serum concentrations of dioxin toxic equivalents were not consistently associated with the sons’ pubertal onset, although a dose-related delay in pubertal onset (only for G2 or higher) was seen among boys who breast-fed for 6 months or more. Conclusions Maternal PCB serum concentrations measured 8 or 9 years after sons’ births—which may reflect sons’ prenatal and early-life exposures—were associated with acceleration in some, but not all, measures of pubertal onset. PMID:21968773

  14. Serum inhibin B in healthy pubertal and adolescent boys: relation to age, stage of puberty, and follicle-stimulating hormone, luteinizing hormone, testosterone, and estradiol levels.

    PubMed

    Andersson, A M; Juul, A; Petersen, J H; Müller, J; Groome, N P; Skakkebaek, N E

    1997-12-01

    increase early in puberty; by pubertal stage II the adult level of inhibin B has been reached. The correlation of inhibin B to FSH, LH, and testosterone changes during pubertal development. Early puberty is characterized by a positive correlation between inhibin B and LH/testosterone, but no correlation to FSH. Late puberty (from stage III) is characterized by a negative correlation between inhibin B and FSH (which is maintained in adult men), a diminishing negative correlation between inhibin B and LH, and no correlation between inhibin B and testosterone, suggesting that developmental and maturational processes in the hypothalamic-pituitary-gonadal axis take place, leading to the establishment of the closed loop feedback regulation system operating in adult men. The positive correlation between inhibin B and LH/ testosterone at the time when serum inhibin B levels rise early in puberty suggests that Leydig cell factors may play an important role in the maturation and stimulation of Sertoli cells in the beginning of pubertal development.

  15. Synaptic number changes in the medial prefrontal cortex across adolescence in male and female rats: A role for pubertal onset.

    PubMed

    Drzewiecki, Carly M; Willing, Jari; Juraska, Janice M

    2016-09-01

    Adolescence is a unique period of development, marked by maturation of the prefrontal cortex (PFC), a region important for executive functioning. During this time, the human PFC decreases in overall volume and thickness. Likewise in adolescent rodents, losses of neurons, dendrites, dendritic spines and neurotransmitter receptors have been documented within the medial prefrontal cortex (mPFC), sometimes with sex and layer specificity. However, changes in the number of synapses during this time have not been examined. In the present study, we stereologically quantified the number of synaptophysin-immunoreactive boutons in the male and female rat mPFC across multiple time points from the juvenile period through adulthood (postnatal days (P) 25, 35, 45, 60 and 90). In females, there was a significant decrease in synaptophysin boutons between P35 and P45, coinciding with the onset of puberty. In males, there was no significant main effect of age on synaptophysin boutons; however, in both males and females, pubertal onset was associated with significant synaptic losses. These results suggest that puberty is a critical period for synaptic pruning within the rat mPFC, potentially contributing to maturation of adolescent executive function. Synapse 70:361-368, 2016. © 2016 Wiley Periodicals, Inc. PMID:27103097

  16. IGF-IR Mediated Mammary Tumorigenesis Is Enhanced during Pubertal Development

    PubMed Central

    Campbell, Craig I.; Moorehead, Roger A.

    2014-01-01

    Although breast cancer typically develops in women over the age of 40, it remains unclear when breast cancer initiating events occur or whether the mammary gland is particularly susceptible to oncogenic transformation at a particular developmental stage. Using MTB-IGFIR transgenic mice that overexpress type I insulin-like growth factor receptor (IGF-IR) in a doxycycline-inducible manner, mammary tumorigenesis was initiated at different developmental stages. Tumor multiplicity was significantly increased while tumor latency was significantly decreased when the IGF-IR transgene was expressed during pubertal development compared to post-pubertal transgene expression. Moreover, metastatic spread of mammary tumors to the lungs was approximately twice as likely when IGF-IR was overexpressed in pubertal mice compared to post-pubertal mice. In addition, engraftment of pubertal MTB-IGFIR mammary tissue into cleared mammary fat pads of pubertal hosts produced tumors more frequently and faster than engraftment into adult hosts. These experiments show that the mammary microenvironment created during puberty renders mammary epithelial cells particularly susceptible to transformation. PMID:25259518

  17. Pubertal cadmium exposure impairs testicular development and spermatogenesis via disrupting testicular testosterone synthesis in adult mice.

    PubMed

    Ji, Yan-Li; Wang, Hua; Liu, Ping; Wang, Qun; Zhao, Xian-Feng; Meng, Xiu-Hong; Yu, Tao; Zhang, Heng; Zhang, Cheng; Zhang, Ying; Xu, De-Xiang

    2010-04-01

    Cadmium (Cd) is a well-known testicular toxicant. However, the effects of pubertal Cd exposure on testicular development and spermatogenesis remained to be elucidated. The present study investigated the effects of pubertal Cd exposure on testicular development and spermatogenesis. Male CD-1 mice were intraperitoneally injected with CdCl(2) (1mg/kg) daily from postnatal day 35 (PND35) to PND70. As expected, pubertal Cd exposure significantly decreased the number of spermatozoa in epididymides. In addition, pubertal Cd exposure markedly reduced the weights of testes, epididymides and prostate and seminal vesicle in adult mice. A significant decrease in serum and testicular testosterone (T) was observed in mice exposed to Cd during puberty. Moreover, pubertal Cd exposure markedly reduced mRNA and protein levels of testicular StAR, P450scc, P450(17alpha) and 17beta-HSD. Taken together, these results suggest that the decreased testicular T synthesis might partially contribute to pubertal Cd-induced impairment on testicular development and spermatogenesis in mice. PMID:19897027

  18. [Disorders of psychosexual maturation in adolescents with residual organic deficiency].

    PubMed

    Gur'eva, V A; Burelov, E A; Kuznetsov, I V; Smirnova, L K

    1991-01-01

    The paper is concerned with disorders of psychosexual maturity in adolescents (n-70). For that purpose in view a comparative nosological study of the early residual organic psychopathlike conditions (46 cases) and of organic psychopathies (24 cases) formed during the pubertal crisis was done at a forensic psychiatry hospital. According to the data obtained in the majority of the test subjects, there occurred asynchronisms of puberty (80%). Unlike group II (organic psychopathy) where disharmonic puberty was predominant, retarded puberty was recorded most frequently in group I. The main variants of psychosexual maturity were distinguished within the framework of the forms indicated: 2 variants in retardation and 6 variants in disharmonic puberty. Disharmonic puberty, then retarded puberty and pubertas precox were found to be dangerous for the onset of sexual disorders (perversions, deviations). Expert criteria for assessing the depth of sexual disorders were specified in addition. The new data obtained are of importance of both general and forensic psychiatry. PMID:1646545

  19. Body size and pubertal development explain ethnic differences in structural geometry at the femur in Asian, Hispanic, and white early adolescent girls living in the U.S.

    PubMed Central

    Osborne, D.L.; Weaver, C.M.; McCabe, L.D.; McCabe, G.M.; Novotny, R.; Van Loan, M.D.; Going, S.; Matkovic, V.; Boushey, C.J.; Savaiano, D.A.

    2012-01-01

    , ethnicity was not a significant predictor in regression models for CSA and Z. Conclusion Variability in bone geometry at the narrow neck of the femur is best explained by body size and pubertal maturation. After controlling for these covariates there were no differences in bone geometry between ethnic groups. PMID:22944607

  20. Endocrine-disrupting chemicals: prepubertal exposures and effects on sexual maturation and thyroid function in the male rat. A focus on the EDSTAC recommendations. Endocrine Disrupter Screening and Testing Advisory Committee.

    PubMed

    Stoker, T E; Parks, L G; Gray, L E; Cooper, R L

    2000-03-01

    Puberty in mammalian species is a period of rapid interactive endocrine and morphological changes. Therefore, it is not surprising that exposure to a variety of pharmaceutical and environmental compounds has been shown to dramatically alter pubertal development. This concern was recognized by the Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) that acknowledged the need for the development and standardization of a protocol for the assessment of the impact of endocrine-disrupting compounds (EDC) in the pubertal male and recommended inclusion of an assay of this type as an alternative test in the EDSTAC tier one screen (EPA, 98). The pubertal male protocol was designed to detect alterations of pubertal development, thyroid function, and hypothalamic-pituitary-gonadal (HPG) system peripubertal maturation. In this protocol, intact 23-day-old weanling male rats are exposed to the test substance for 30 days during which pubertal indices are measured. After necropsy, reproductive and thyroid tissues are weighed and evaluated histologically and serum taken for hormone analysis. The purpose of this review was to examine the available literature on pubertal development in the male rat and evaluate the efficacy of the proposed protocol for identifying endocrine-disrupting chemicals. The existing data indicate that this assessment of puberty in the male rat is a simple and effective method to detect the EDC activity of pesticides and toxic substances.

  1. Early morning plasma testosterone is an accurate predictor of imminent pubertal development in prepubertal boys.

    PubMed

    Wu, F C; Brown, D C; Butler, G E; Stirling, H F; Kelnar, C J

    1993-01-01

    In the management of constitutional delayed growth and/or puberty, there is a need for simple tests which can assess the overall developmental maturity of the hypothalamic-pituitary-testicular axis in clinically prepubertal patients. This would enable the physician to predict the likelihood or otherwise of an individual entering puberty spontaneously within subsequent months. Based on our previous physiological data on the sequential pattern of peripubertal pituitary-testicular activation by hypothalamic GnRH, we hypothesized that the nocturnal secretion of testosterone, in response to sleep-entrained LH secretion, may provide a basis for an in vivo bioassay of neuroendocrine sexual maturity. Overnight testosterone secretion by the testis in clinically prepubertal boys was assessed with respect to their subsequent clinical progress, the target being the attainment of testicular volumes of greater than or equal to 4 mL (a clinical landmark when puberty has assuredly begun and virilization will soon follow). Forty-five prepubertal (Tanner stage G1PH1 testicular volume < or = 2 mL) boys aged 10.0-15.3 yr (mean +/- SEM 11.8 +/- 0.2) with short stature had paired plasma T concentration measured at 2000 h and 0800 h the following morning. After the initial assessment, all patients were reviewed clinically at 3-month intervals for a minimum of 21 months (mean 26.0 +/- 1.1, range 21-50 months). During this period, 38 (84.4%) patients received treatment in the form of sc human GH 2-4 IU daily or oxandrolone 2.5 mg daily by mouth to improve short-term growth although this did not have any significant effect on the subsequent timing of pubertal onset. The patients were divided according to whether 1) there was a demonstrable increase in plasma T between 2000 and 0800 h and 2) morning plasma T concentration was less than or greater than or equal to 0.7 nmol/L at their initial assessment. In those with a significant overnight T increment, 58% and 89% achieved testicular volume

  2. Race and perceived pubertal transition effects on girls' depressive symptoms and delinquent behaviors.

    PubMed

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

    2013-08-01

    Most past research on the effects of early pubertal timing on girls' depressive symptoms and delinquent behavior has focused on either age of menarche or has combined multiple indicators of development into a single index of puberty. Past research has rarely examined both the onset of puberty such as age of menarche, as well more psychologically mediated impressions of puberty (i.e., perceived pubertal timing) within the same study. This study extends past research on racial differences and pubertal related effects on girls' depressive symptoms and delinquent behavior by examining the independent influence of different indicators of puberty (age of menarche, development of breasts, and perceived pubertal timing). Two waves of data (100% females) were used from African Americans (N = 481) and European Americans (N = 1259) who were enrolled in seventh- and eighth-grade during the first wave of data collection in the National Longitudinal Study of Adolescent Health. Early age of menarche was associated with high levels of depressive symptoms at Wave 1. Additionally, both early and late perceived pubertal timing were associated with high levels of depressive symptoms and high delinquent behaviors at Wave 1. The structural relationships among these variables were similar for African Americans and European Americans. Age of menarche and perceived pubertal timing influenced depressive symptoms and delinquent behavior at Wave 2 through depressive symptoms and delinquent behavior reported at Wave 1. The implications of these findings are discussed with an emphasis on how the specific indicator used to assess puberty is important in efforts to understand pubertal timing effects.

  3. Rituximab pharmacokinetics in children and adolescents with de novo intermediate and advanced mature B-cell lymphoma/leukaemia: a Children's Oncology Group report.

    PubMed

    Barth, Matthew J; Goldman, Stanton; Smith, Lynette; Perkins, Sherrie; Shiramizu, Bruce; Gross, Thomas G; Harrison, Lauren; Sanger, Warren; Geyer, Mark B; Giulino-Roth, Lisa; Cairo, Mitchell S

    2013-09-01

    The ANHL01P1 trial was undertaken to determine pharmacokinetics and safety following the addition of rituximab to French-American-British/Lymphome Malins de Burkitt (FAB/LMB96) chemotherapy in 41 children and adolescents with Stage III/IV mature B-cell lymphoma/leukaemia. Patients received rituximab (375 mg/m(2) ) days -2 and 0 of two induction cycles and day 0 of two consolidation cycles. Highest peak levels were achieved following the second dose of each induction cycle [299 ± 19 and 384 ± 25 μg/ml (Group-B); 245 ± 31 and 321 ± 32 μg/ml (Group-C)] with sustained troughs and t½ of 26-29 d. Rituximab can be safely added to FAB chemotherapy with high early rituximab peak/trough levels and a long t½. PMID:23802659

  4. Plasma adrenal and gonadal sex steroids in human pubertal development.

    PubMed

    Ducharme, J R; Forest, M G; De Peretti, E; Sempé, M; Collu, R; Bertrand, J

    1976-03-01

    Plasma free dehydroepiandrosterone (DHA), androstenedione (delta), testosterone (T), dihydrotestosterone (DHT), estrone (E1), and estradiol (E2) were measured by radioimmunoassay in 55 boys and 54 girls 3.5 to 16.3 years of age. Plasma DHA increased significantly between 6 and 8 years of age in girls and between 8 and 10 years of age in boys. A further significant increase was noted between 10 and 12 years of age in both sexes. Delta rose significantly between 8 and 10 years of age in girls and between 10 and 12 years in boys. In contrast, no significant increase in T, DHT, or E1, was noted prior to 12 years of age in both sexes. However, E2 showed a significant increase between 10 and 12 years of age in girls. This early rise in the course of pubertal development of the two sex steroids predominantly of adrenal origin, DHA and delta, and its occurence 1 to 2 years earlier in girls than in boys, as does puberty itself, suggest a possible role for these steroids in the mechanisms involved in triggering the hypothalamic-pituitary-gonadal axis at puberty.

  5. Hypothyroidism affects pulsatile LH secretion in pubertal orchiectomized rats.

    PubMed

    Maia, A L; Favaretto, A L; Carvaho, T L; Rodrigues, J A; Iazigi, N

    1995-08-01

    The present study evaluated the effect of hypothyroidism on the pituitary-testicular axis in rats rendered hypothyroid on the beginning of puberty. Rats were treated with propylthiouracil for 8 weeks and killed for determination of hormonal status and body parameters. For determination of pulsatile LH secretion other animals were orchiectomized two weeks before sampling. Analysis of the results led us to conclude that although the absolute weight of sex organs tended to decrease in hypothyroid animals, the relative weights were equal or higher than control, suggesting that the development of these organs were not affected by hypothyroidism; the androgenic activity of hypothyroid rat testes were preserved; basal plasma levels of pituitary hormones were similar in control and hypothyroid groups; the pulsatile LH secretion showed a decrease in the number of pulses, nadir mean and total LH secretion in hypothyroid animals. Our results demonstrate that although hypothalamic-pituitary axis of hypothyroid pubertal rats displays an abnormal pulsation LH release, no evidences of abnormalities in the reproductive system functions were found.

  6. Attachment, parenting styles and bullying during pubertal years.

    PubMed

    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. PMID:25533411

  7. Attachment, parenting styles and bullying during pubertal years.

    PubMed

    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.

  8. From Crescent to Mature Virion: Vaccinia Virus Assembly and Maturation

    PubMed Central

    Liu, Liang; Cooper, Tamara; Howley, Paul M.; Hayball, John D.

    2014-01-01

    Vaccinia virus (VACV) has achieved unprecedented success as a live viral vaccine for smallpox which mitigated eradication of the disease. Vaccinia virus has a complex virion morphology and recent advances have been made to answer some of the key outstanding questions, in particular, the origin and biogenesis of the virion membrane, the transformation from immature virion (IV) to mature virus (MV), and the role of several novel genes, which were previously uncharacterized, but have now been shown to be essential for VACV virion formation. This new knowledge will undoubtedly contribute to the rational design of safe, immunogenic vaccine candidates, or effective antivirals in the future. This review endeavors to provide an update on our current knowledge of the VACV maturation processes with a specific focus on the initiation of VACV replication through to the formation of mature virions. PMID:25296112

  9. Oocyte cryopreservation for fertility preservation in post-pubertal female children at risk for premature ovarian failure due to accelerated follicle loss in Turner Syndrome or cancer treatments

    PubMed Central

    Oktay, K; Bedoschi, G

    2014-01-01

    Objective To preliminarily study the feasibility of oocyte cryopreservation in post-pubertal girls aged between 13 and 15 years who were at risk for premature ovarian failure due to the accelerated follicle loss associated with Turner’s Syndrome or cancer treatments. Design Retrospective cohort and review of literature. Setting Academic fertility preservation unit. Participants Three girls diagnosed with Turner syndrome, one girl diagnosed with germ-cell tumor and one girl diagnosed with lymphoblastic leukemia. Interventions Assessment of ovarian reserve, ovarian stimulation, oocyte retrieval, in vitro maturation, and mature oocyte cryopreservation. Main Outcome Measure Response to ovarian stimulation, number of mature oocytes cryopreserved and complications, if any. Results Mean AMH, baseline FSH, Estradiol and antral follicle counts were 1.30 ± 0.39, 6.08 ± 2.63, 41.39 ± 24.68, 8.0 ± 3.2; respectively. In Turner girls the ovarian reserve assessment indicated already diminished ovarian reserve. Ovarian stimulation and oocyte cryopreservation was successfully performed in all female children referred for fertility preservation. A range of 4–11 mature oocytes (mean 8.1 ± 3.4) was cryopreserved without any complications. All girls tolerated the procedure well. Conclusions Oocyte cryopreservation is a feasible technique in selected female children at risk for premature ovarian failure. Further studies would be beneficial to test the success of oocyte cryopreservation in young girls. PMID:25214440

  10. CFD - Mature Technology?

    NASA Technical Reports Server (NTRS)

    Kwak, Dochan

    2005-01-01

    Over the past 30 years, numerical methods and simulation tools for fluid dynamic problems have advanced as a new discipline, namely, computational fluid dynamics (CFD). Although a wide spectrum of flow regimes are encountered in many areas of science and engineering, simulation of compressible flow has been the major driver for developing computational algorithms and tools. This is probably due to a large demand for predicting the aerodynamic performance characteristics of flight vehicles, such as commercial, military, and space vehicles. As flow analysis is required to be more accurate and computationally efficient for both commercial and mission-oriented applications (such as those encountered in meteorology, aerospace vehicle development, general fluid engineering and biofluid analysis) CFD tools for engineering become increasingly important for predicting safety, performance and cost. This paper presents the author's perspective on the maturity of CFD, especially from an aerospace engineering point of view.

  11. Pubertal development and school transition. Joint influences on depressive symptoms in middle and late adolescents.

    PubMed

    Koenig, L J; Gladstone, T R

    1998-07-01

    The impact of simultaneous changes in biological and social context on the mental health of adolescents was examined by testing the hypothesis that normative developmental transitions can be associated with increased dysphoria if they occur in close temporal proximity. Girls experiencing physical changes associated with middle or later stage pubertal development during the initial high school or college year were predicted to experience more dysphoria than those experiencing these changes during non-transitional times, with negative pubertal attitudes exacerbating the relation. Pubertal status and dysphoria of high school and college students were assessed. Among females experiencing pubertal changes, dysphoria was indeed highest for the 15 and 19 year olds, and lower for the 16, 17, and 18 year olds with females viewing menstrual onset as negative experienced depressive symptoms of moderate clinical severity. This pattern did not emerge for males, or females not experiencing pubertal changes. In contrast, the hypothesis was not supported when transition time was operationalized using grade level. Implications for psychopathology risk are discussed.

  12. Developmental competence and embryo quality of small oocytes from pre-pubertal goats cultured in IVM medium supplemented with low level of hormones, insulin-transferrin-selenium and ascorbic acid.

    PubMed

    Hammami, S; Morató, R; Romaguera, R; Roura, M; Catalá, M G; Paramio, M T; Mogas, T; Izquierdo, D

    2013-04-01

    The aim of this study was to test the effect of insulin-transferrin-selenium (ITS) and L-ascorbic acid (AA) supplementation and the hormonal level during in vitro maturation (IVM) of small oocytes from pre-pubertal goat on the blastocyst yield and quality. Concretely, we used four maturation media: conventional IVM medium (CM), growth medium (GM: CM+ITS+AA and low level of hormones), modified CM (mCM: CM with low level of hormones) and modified GM (mGM: CM+ITS+AA and normal level of hormones). Cumulus-oocyte complexes (COCs) were classified into two categories according to oocyte diameter: <125 μm and ≥ 125 μm. Large oocytes were matured 24 h in CM (Treatment A). Small oocytes were matured randomly in six experimental groups: Treatment B: 24 h in CM; Treatment C: 12 h in GM and 12 h in CM; Treatment D: 24 h in mGM; Treatment E: 12 h in mGM and 12 h in CM; Treatment F: 12 h in mCM and 12 h in CM; and Treatment G: 12 h in GM and 12 h in mGM. After IVM, oocytes were fertilized and cultured for 8 days. The blastocyst quality was assessed by the survival following vitrification/warming and the mean cell number. When different maturation media were combined, the blastocyst rate did not improve. The large oocytes produced the highest blastocysts yield. However, the culture of small oocytes in GM (53.3%) enhanced the post-warming survival of blastocysts compared to large oocytes matured in CM (35.7%). In conclusion, IVM of pre-pubertal goat small oocytes in GM would be useful to improve the quality of in vitro-produced blastocysts.

  13. Therapy of advanced-stage mature B-cell lymphoma and leukemia in children and adolescents with rituximab and reduced intensity induction chemotherapy (B-NHL 2004M protocol): the results of a multicenter study.

    PubMed

    Samochatova, Elena V; Maschan, Alexey A; Shelikhova, Larisa N; Myakova, Natalia V; Belogurova, Margarita B; Khlebnikova, Olga P; Shamardina, Anastasia V; Ryskal, Olga V; Roumiantseva, Julia V; Konovalov, Dmitriy M; Dubrovina, Maria E; Rumyantsev, Alexander G

    2014-07-01

    Pediatric mature B-cell non-Hodgkin lymphomas (B-NHLs) are highly aggressive malignant tumors that are curable with chemotherapy (ChT). High-dose methotrexate (MTX) is considered indispensable for successful treatment, but this therapy frequently induces severe mucositis and infectious complications, especially in induction, which can cause treatment failure. A prospective multicenter trial of combined immunochemotherapy for advanced-stage B-NHL with rituximab and the modified NHL-BFM-90 protocol was conducted. The major differences from the original protocol were a decrease in the dose of MTX from 5000 to 1000 mg/m/24 h in the first 2 ChT blocks and the addition of rituximab at 375 mg/m to each of the first 4 blocks of ChT. Eighty-three newly diagnosed patients with a median age of 8.84 years with Burkitt lymphoma/leukemia and diffuse large B-cell lymphomas stage III to IV were included. Four patients died during induction ChT due to tumor lysis syndrome and infection. Two additional patients died subsequently due to tumor resistance. Complete remission was achieved in 77 (92.8%) patients; 2 patients relapsed at 1 and 3 months, and 2 developed secondary malignancies at 1 and 6.5 years, respectively, after the completion of therapy. The overall survival probability was 82%±8% with a median follow-up of 65.2 months. Combined therapy with rituximab and intensive ChT with a reduced MTX dose of 1 g/m in the 2 induction courses was feasible and produced high cure rates in patients with pediatric advanced-stage mature B-NHL. PMID:23823112

  14. Self-Rated Pubertal Development, Depressive Symptoms and Delinquency: Measurement Issues and Moderation by Gender and Maltreatment

    ERIC Educational Resources Information Center

    Negriff, Sonya; Fung, Michelle T.; Trickett, Penelope K.

    2008-01-01

    This cross-sectional study examined relationships between pubertal development, depressive symptoms and delinquency in a sample of 241 males and 213 females aged 9-13 years. Four objectives were set forth for this study: (1) to examine relationships between pubertal stage or timing and depressive symptoms and delinquency; (2) to compare continuous…

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

    ERIC Educational Resources Information Center

    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…

  16. Comparison of Examination Methods Used in the Evaluation of Prepubertal and Pubertal Female Genitalia: A Descriptive Study

    ERIC Educational Resources Information Center

    Boyle, Cathy; McCann, John; Miyamoto, Sheridan; Rogers, Kristen

    2008-01-01

    Objective: To compare the effectiveness of three different examination methods in their ability to help the examiner detect both acute and non-acute genital injuries in prepubertal and pubertal girls suspected of having been sexually abused. Methods: Forty-six prepubertal and 74 pubertal girls, whose ages ranged from 4 months to 18 years, were…

  17. Pubertal Timing, Peer Victimization, and Body Esteem Differentially Predict Depressive Symptoms in African American and Caucasian Girls

    ERIC Educational Resources Information Center

    Hamlat, Elissa J.; Shapero, Benjamin G.; Hamilton, Jessica L.; Stange, Jonathan P.; Abramson, Lyn Y.; Alloy, Lauren B.

    2015-01-01

    This study prospectively examined pubertal timing and peer victimization as interactive predictors of depressive symptoms in a racially diverse community sample of adolescents. We also expanded on past research by assessing body esteem as a mechanism by which pubertal timing and peer victimization confer risk for depression. In all, 218…

  18. Pubertal Timing and Its Link to Behavioral and Emotional Problems among "At-Risk" African American Adolescent Girls

    ERIC Educational Resources Information Center

    Carter, Rona; Jaccard, James; Silverman, Wendy K.; Pina, Armando A.

    2009-01-01

    Using an "at-risk" sample of African American girls, the present study examined the link between girls' retrospective reports of pubertal timing, girls' perceived relative pubertal timing, and their behavioral and emotional problems as rated by the girls themselves (N = 102; 11-17 years), as well as teachers and parents. Structural equation…

  19. Relationships of Pubertal Development Among Early Adolescents to Sexual and Nonsexual Risk Behaviors and Caregivers' Parenting Behaviors

    PubMed Central

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

    2011-01-01

    Using a school-based sample of Washington, DC, fifth graders (mean age 10.38, SD = 0.66) and their parents (N = 408), we examined 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. Youths reporting signs of pubertal development were more likely to engage in these risk behaviors than students reporting no signs. Pubertal development was not related to parenting behaviors; however, parents of youths who reported multiple nonsexual risk behaviors reported more parent-child communication about sexual topics. These results highlight the need to begin risk prevention efforts early, prior to pubertal development. Research is needed to understand how parents can help youths better cope with pubertal development to avoid involvement in sexual and nonsexual risk behaviors. PMID:21808444

  20. Pubertal status moderates the association between mother and child laboratory pain tolerance

    PubMed Central

    Tsao, Jennie CI; Li, Ning; Parker, Delana; Seidman, Laura C; Zeltzer, Lonnie K

    2014-01-01

    BACKGROUND: There is limited information regarding the relationship between parent and child responses to laboratory pain induction in the absence of experimental manipulation. OBJECTIVES: To assess the association between responses to cold and pressure pain tasks in 133 nonclinical mothers and children (mean age 13.0 years; 70 girls), and the moderating effects of child sex and pubertal status on these mother-child relationships. METHODS: Mothers and children independently completed the cold and pressure pain tasks. Multiple linear regression analyses examined the association between mothers’ and children’s laboratory pain responses. The moderating effects of child sex and pubertal status were tested in the linear models by examining the interaction among mother laboratory pain responses, and child sex and pubertal status. RESULTS: Mothers’ cold pain anticipatory anxiety and pressure pain intensity were associated with children’s pressure pain anticipatory anxiety. Mothers’ pressure pain tolerance was associated with children’s pain tolerance for both the cold and pressure pain tasks. Mothers’ cold pain tolerance was associated with children’s pressure pain tolerance. Pubertal status moderated two of the three significant mother-child pain tolerance relationships, such that the associations held for early pubertal but not for late pubertal children. Sex did not moderate mother-child pain associations. CONCLUSIONS: The results indicate that mother-child pain relationships are centred primarily on pain avoidance behaviour, particularly among prepubertal children. These findings may inform interventions focused on pain behaviours, with a particular emphasis on mothers of prepubertal children, to reduce acute pain responses in their children. PMID:24367794

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

    PubMed Central

    Tavares, Aline Cristina; Bocchi, Edimar Alcides; Guimarães, Guilherme Veiga

    2012-01-01

    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. PMID:22473410

  2. Gene expression in the brain-pituitary adipose tissue axis and luteinising hormone secretion during pubertal development in the gilt.

    PubMed

    Barb, C R; Hausman, G J; Rekaya, R

    2006-01-01

    The occurrence of puberty in the female is due to the interplay of central and peripheral mechanisms in which the hypothalamic-pituitary-ovarian axis regulates growth and gonadal function, as well as adipocyte hormone secretion. Hypothalamic GnRH mRNA expression increased at 3.5 months of age and declined by 6 months of age. Concomitant with the age related reduction in the oestrogen negative feedback on LH secretion was a decline in hypothalamic oestrogen receptor-alpha (ERalpha) expression and increased expression of repressor of ER activity gene (REA) at 210 days of age. Hypothalamic proopiomelanocortin expression increased at 6 months of age followed by increased expression of progesterone receptor (PR) membrane compliment-1 and steroid membrane binding protein gene at 210 days of age. This represents development of the endogenous opioid peptide-progesterone dependent LH inhibitory pathway. Adipose tissue leptin and insulin like growth factor-I (IGF-I) gene expression increased with age and adiposity. Pituitary transcription factors, steroidogenic factor 1 (SF1) and Lhx3, and LHbeta and FSHbeta gene expression increased with age. These results identify key hypothalamic and pituitary genes associated with changes in LH secretion and growth during pubertal development and adipose tissue genes and secreted proteins related to maturation of the neuroendocrine axis and puberty.

  3. Pubertal status, pre-meal drink composition, and later meal timing interact in determining children's appetite and food intake.

    PubMed

    Patel, Barkha P; Hamilton, Jill K; Vien, Shirley; Thomas, Scott G; Anderson, G Harvey

    2016-09-01

    Puberty is a period of development that alters energy intake patterns. However, few studies have examined appetite and food intake (FI) regulation during development of puberty in children and adolescents. Therefore, the objective was to measure the effect of pubertal status on FI and subjective appetite after pre-meal glucose and whey protein drinks in 9- to 14-year-old boys and girls. In a within-subject, randomized, repeated-measures design, children (21 pre-early pubertal, 15 mid-late pubertal) received equally sweetened drinks containing Sucralose (control), glucose, or whey protein (0.75 g/kg body weight) in 250 mL of water 2 h after a standardized breakfast on 6 separate mornings. Ad libitum FI was measured either 30 or 60 min later and appetite was measured over time. In pre-early and mid-late pubertal boys and girls there was no effect of sex on total FI (kcal). Glucose and whey protein drinks reduced calorie intake similarly at 30 min. But at 60 min, whey protein reduced FI (p < 0.001) compared with control and glucose in pre-early pubertal children, but not in mid-late pubertal children. However, sex was a factor (p = 0.041) when FI was expressed per kilogram body weight. Pubertal status did not affect FI/kilogram body weight in boys, but it was 32% lower in mid-late pubertal girls than at pre-early puberty (p = 0.010). Appetite was associated with FI in mid-late pubertal children only. In conclusion, pubertal development affects appetite and FI regulation in children. PMID:27507005

  4. Peri-pubertal exposure to testicular hormones organizes response to novel environments and social behaviour in adult male rats.

    PubMed

    Brown, Gillian R; Kulbarsh, Kyle D; Spencer, Karen A; Duval, Camille

    2015-07-01

    Previous research has shown that exposure to testicular hormones during the peri-pubertal period of life has long-term, organizational effects on adult sexual behaviour and underlying neural mechanisms in laboratory rodents. However, the organizational effects of peri-pubertal testicular hormones on other aspects of behaviour and brain function are less well understood. Here, we investigated the effects of manipulating peri-pubertal testicular hormone exposure on later behavioural responses to novel environments and on hormone receptors in various brain regions that are involved in response to novelty. Male rodents generally spend less time in the exposed areas of novel environments than females, and this sex difference emerges during the peri-pubertal period. Male Lister-hooded rats (Rattus norvegicus) were castrated either before puberty or after puberty, then tested in three novel environments (elevated plus-maze, light-dark box, open field) and in an object/social novelty task in adulthood. Androgen receptor (AR), oestrogen receptor (ER1) and corticotropin-releasing factor receptor (CRF-R2) mRNA expression were quantified in the hypothalamus, hippocampus and medial amygdala. The results showed that pre-pubertally castrated males spent more time in the exposed areas of the elevated-plus maze and light-dark box than post-pubertally castrated males, and also confirmed that peri-pubertal hormone exposure influences later response to an opposite-sex conspecific. Hormone receptor gene expression levels did not differ between pre-pubertally and post-pubertally castrated males in any of the brain regions examined. This study therefore demonstrates that testicular hormone exposure during the peri-pubertal period masculinizes later response to novel environments, although the neural mechanisms remain to be fully elucidated.

  5. Effect of pubertal developmental stages and lower limb kinetics during vertical jump task in Sepak Takraw sport.

    PubMed

    Leonard Joseph, H; Roslizawati, N; Safrusahar, M Y; Efri, N M H; Das, S; Baharudin, O; Pharmy, A

    2009-01-01

    Sepak Takraw is a sport which actively involves the lower limb. A cross sectional study was performed to investigate the lower limb kinetics (ground reaction force, flight time and contact time) involved during the vertical jumping and landing task between the early pubertal and late pubertal stages in National level Sepak Takraw athletes in Malaysia. Twenty athletes (8 pre pubertal and 12 late pubertal) with no previous history of any physical injuries were taken for the study. The kinetics data of the vertical jump task was calculated using a force platform 3-AMTI Biomechanics Force Platform. The Silicon ProCoach (Chart 5 software) was used to collect the ground reaction force signals, flight time and contact time. The results showed a non-significant decrease in peak ground reaction force in the post pubertal group as compared to the pre pubertal group (t(18)=0.659, p=0.518,CI(95)(-2.54, 4.86). Comparison of flight time between the two age groups showed a significant increase in the post pubertal group with mean and SD (0.7773 + or - 0.03) as compared to the pre pubertal group mean and SD (0.7296 + or - 0.05), which was statistically considered significant (p<0.05) (t(18)=-2.401, p<0.05,CI(95)(-0.089, -0.005). The findings from this study demonstrated that the flight time of the vertical jump task differed between the pre and post pubertal athletes with the post pubertal group having an improved ability in maintaining longer duration of flight phase.

  6. Peri-pubertal exposure to testicular hormones organizes response to novel environments and social behaviour in adult male rats

    PubMed Central

    Brown, Gillian R.; Kulbarsh, Kyle D.; Spencer, Karen A.; Duval, Camille

    2015-01-01

    Previous research has shown that exposure to testicular hormones during the peri-pubertal period of life has long-term, organizational effects on adult sexual behaviour and underlying neural mechanisms in laboratory rodents. However, the organizational effects of peri-pubertal testicular hormones on other aspects of behaviour and brain function are less well understood. Here, we investigated the effects of manipulating peri-pubertal testicular hormone exposure on later behavioural responses to novel environments and on hormone receptors in various brain regions that are involved in response to novelty. Male rodents generally spend less time in the exposed areas of novel environments than females, and this sex difference emerges during the peri-pubertal period. Male Lister-hooded rats (Rattus norvegicus) were castrated either before puberty or after puberty, then tested in three novel environments (elevated plus-maze, light–dark box, open field) and in an object/social novelty task in adulthood. Androgen receptor (AR), oestrogen receptor (ER1) and corticotropin-releasing factor receptor (CRF-R2) mRNA expression were quantified in the hypothalamus, hippocampus and medial amygdala. The results showed that pre-pubertally castrated males spent more time in the exposed areas of the elevated-plus maze and light–dark box than post-pubertally castrated males, and also confirmed that peri-pubertal hormone exposure influences later response to an opposite-sex conspecific. Hormone receptor gene expression levels did not differ between pre-pubertally and post-pubertally castrated males in any of the brain regions examined. This study therefore demonstrates that testicular hormone exposure during the peri-pubertal period masculinizes later response to novel environments, although the neural mechanisms remain to be fully elucidated. PMID:26159287

  7. Neonatal olfactory bulbectomy enhances locomotor activity, exploratory behavior and binding of NMDA receptors in pre-pubertal rats.

    PubMed

    Flores, G; Ibañez-Sandoval, O; Silva-Gómez, A B; Camacho-Abrego, I; Rodríguez-Moreno, A; Morales-Medina, J C

    2014-02-14

    In this study, we investigated the effect of neonatal olfactory bulbectomy (nOBX) on behavioral paradigms related to olfaction such as exploratory behavior, locomotor activity in a novel environment and social interaction. We also studied the effect of nOBX on the activity of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors during development. The behavioral effects of nOBX (postnatal day 7, PD7) were investigated in pre- (PD30) and post-pubertal (PD60) Wistar rats. NMDA receptor activity was measured with [(125)I]MK-801 in the brain regions associated with the olfactory circuitry. A significant increase in the novelty-induced locomotion was seen in the pre-pubertal nOBX rats. Although the locomotor effect was less marked than in pre-pubertal rats, the nOBX rats tested post-pubertally failed to habituate to the novel situation as quickly as the sham- and normal- controls. Pre-pubertally, the head-dipping behavior was enhanced in nOBX rats compared with sham-operated and normal controls, while normal exploratory behavior was observed between groups in adulthood. In contrast, social interaction was increased in post-pubertal animals that underwent nOBX. Both pre- and post-pubertal nOBX rats recovered olfaction. Interestingly, pre-pubertal rats showed a significant increase in the [(125)I]MK-801 binding in the piriform cortex, dorsal hippocampus, inner and outer layers of the frontal cortex and outer layer of the cingulate cortex. At post-pubertal age, no significant differences in [(125)I]MK-801 binding were observed between groups at any of the brain regions analyzed. These results suggest that nOBX produces pre-pubertal behavioral disturbances and NMDA receptor changes that are transitory with recovery of olfaction early in adulthood. PMID:24295633

  8. Neonatal olfactory bulbectomy enhances locomotor activity, exploratory behavior and binding of NMDA receptors in pre-pubertal rats.

    PubMed

    Flores, G; Ibañez-Sandoval, O; Silva-Gómez, A B; Camacho-Abrego, I; Rodríguez-Moreno, A; Morales-Medina, J C

    2014-02-14

    In this study, we investigated the effect of neonatal olfactory bulbectomy (nOBX) on behavioral paradigms related to olfaction such as exploratory behavior, locomotor activity in a novel environment and social interaction. We also studied the effect of nOBX on the activity of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors during development. The behavioral effects of nOBX (postnatal day 7, PD7) were investigated in pre- (PD30) and post-pubertal (PD60) Wistar rats. NMDA receptor activity was measured with [(125)I]MK-801 in the brain regions associated with the olfactory circuitry. A significant increase in the novelty-induced locomotion was seen in the pre-pubertal nOBX rats. Although the locomotor effect was less marked than in pre-pubertal rats, the nOBX rats tested post-pubertally failed to habituate to the novel situation as quickly as the sham- and normal- controls. Pre-pubertally, the head-dipping behavior was enhanced in nOBX rats compared with sham-operated and normal controls, while normal exploratory behavior was observed between groups in adulthood. In contrast, social interaction was increased in post-pubertal animals that underwent nOBX. Both pre- and post-pubertal nOBX rats recovered olfaction. Interestingly, pre-pubertal rats showed a significant increase in the [(125)I]MK-801 binding in the piriform cortex, dorsal hippocampus, inner and outer layers of the frontal cortex and outer layer of the cingulate cortex. At post-pubertal age, no significant differences in [(125)I]MK-801 binding were observed between groups at any of the brain regions analyzed. These results suggest that nOBX produces pre-pubertal behavioral disturbances and NMDA receptor changes that are transitory with recovery of olfaction early in adulthood.

  9. The thyroid hormone receptor gene (c-erbA alpha) is expressed in advance of thyroid gland maturation during the early embryonic development of Xenopus laevis.

    PubMed Central

    Banker, D E; Bigler, J; Eisenman, R N

    1991-01-01

    The c-erbA proto-oncogene encodes the thyroid hormone receptor, a ligand-dependent transcription factor which plays an important role in vertebrate growth and development. To define the role of the thyroid hormone receptor in developmental processes, we have begun studying c-erbA gene expression during the ontogeny of Xenopus laevis, an organism in which thyroid hormone has well-documented effects on morphogenesis. Using polymerase chain reactions (PCR) as a sensitive assay of specific gene expression, we found that polyadenylated erbA alpha RNA is present in Xenopus cells at early developmental stages, including the fertilized egg, blastula, gastrula, and neurula. By performing erbA alpha-specific PCR on reverse-transcribed RNAs from high-density sucrose gradient fractions prepared from early-stage embryos, we have demonstrated that these erbA transcripts are recruited to polysomes. Therefore, erbA is expressed in Xenopus development prior to the appearance of the thyroid gland anlage in tailbud-stage embryos. This implies that erbA alpha/thyroid hormone receptors may play ligand-independent roles during the early development of X. laevis. Quantitative PCR revealed a greater than 25-fold range in the steady-state levels of polyadenylated erbA alpha RNA across early stages of development, as expressed relative to equimolar amounts of total embryonic RNA. Substantial increases in the levels of erbA alpha RNA were noted at stages well after the onset of zygotic transcription at the mid-blastula transition, with accumulation of erbA alpha transcripts reaching a relative maximum in advance of metamorphosis. We also show that erbA alpha RNAs are expressed unequally across Xenopus neural tube embryos. This differential expression continues through later stages of development, including metamorphosis. This finding suggests that erbA alpha/thyroid hormone receptors may play roles in tissue-specific processes across all of Xenopus development. Images PMID:1656222

  10. Genetics of Bone Mass in Childhood and Adolescence: Effects of Sex and Maturation Interactions.

    PubMed

    Mitchell, Jonathan A; Chesi, Alessandra; Elci, Okan; McCormack, Shana E; Kalkwarf, Heidi J; Lappe, Joan M; Gilsanz, Vicente; Oberfield, Sharon E; Shepherd, John A; Kelly, Andrea; Zemel, Babette S; Grant, Struan F A

    2015-09-01

    We aimed to determine if adult bone mineral density (BMD) susceptibility loci were associated with pediatric bone mass and density, and if sex and pubertal stage influenced any association. We analyzed prospective areal BMD (aBMD) and bone mineral content (BMC) data from the Bone Mineral Density in Childhood Study (n = 603, European ancestry, 54% female). Linear mixed models were used to assess if 77 single-nucleotide polymorphisms (SNPs) near known adult BMD susceptibility loci interacted with sex and pubertal stage to influence the aBMD/BMC; adjusting for age, BMI, physical activity, and dietary calcium. The strongest main association was observed between an SNP near C7orf58 and distal radius aBMD. However, this association had a significant sex • SNP interaction, revealing a significant association only in females (b = -0.32, p = 1.8 × 10(-6)). Furthermore, the C12orf23 locus had significant interactions with both sex and pubertal stage, revealing associations in females during Tanner stage I for total hip aBMD (b = 0.24, p = 0.001) and femoral neck aBMD (b = 0.27, p = 3.0 × 10(-5)). In contrast, the sex • SNP interactions for loci near LRP5 and WNT16 uncovered associations that were only in males for total body less head BMC (b = 0.22, p = 4.4 × 10(-4)) and distal radius aBMD (b = 0.27, p = 0.001), respectively. Furthermore, the LRP5 locus interacted with both sex and pubertal stage, demonstrating associations that were exclusively in males during Tanner V for total hip aBMD (b = 0.29, p = 0.003). In total, significant sex • SNP interactions were found at 15 loci; pubertal stage • SNP interactions at 23 loci and 19 loci interacted with both sex and pubertal stage. In conclusion, variants originally associated with adult BMD influence bone mass in children of European ancestry, highlighting the fact that many of these loci operate early in life. However, the direction and magnitude of associations for a large number of SNPs only became evident when

  11. Grade, Pubertal Status, and Gender Related Variations in Conflictual Issues among Adolescents.

    ERIC Educational Resources Information Center

    Papini, Dennis R.; Savage, Catherine L.

    It is possible that conflicts in families with adolescents are linked to the transitions and individual development that occur during adolescence. A study was conducted to describe domains of conflictual issues associated with adolescent grade in school, pubertal status, and gender. The sample was comprised of 78 seventh graders, 115 ninth…

  12. Grade, Pubertal Status, and Gender-Related Variations in Conflictual Issues among Adolescents.

    ERIC Educational Resources Information Center

    Papini, Dennis R.; And Others

    1989-01-01

    Junior and senior high school students (N=279) completed measures of pubertal status, demographics, and Issues Checklist. Intensity of School Issues and Household Behavior Issues was greater among seventh and ninth graders than among eleventh graders. Self-Responsibility Issues were most intense among transpubertal adolescents. Boys perceived more…

  13. Longitudinal Changes in Marital Relationships: The Role of Offspring's Pubertal Development

    ERIC Educational Resources Information Center

    Whiteman, Shawn D.; McHale, Susan M.; Crouter, Ann C.

    2007-01-01

    This study charted the longitudinal trajectories of wives' and husbands' reports of marital love, satisfaction, and conflict and explored whether and how first- and second-born offspring's pubertal development was related to marital changes. Data were drawn from the first 7 years of a longitudinal study of family relationships. Participants…

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

    ERIC Educational Resources Information Center

    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…

  15. Pubertal Effects on Adjustment in Girls: Moving from Demonstrating Effects to Identifying Pathways

    ERIC Educational Resources Information Center

    Graber, Julia A.; Brooks-Gunn, Jeanne; Warren, Michelle P.

    2006-01-01

    The present investigation examines mediated pathways from pubertal development to changes in depressive affect and aggression. Participants were 100 white girls who were between the ages of 10 and 14 (M=12.13, SD=0.80); girls were from well-educated, middle-to upper-middle class families, and attended private schools in a major northeastern urban…

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

    ERIC Educational Resources Information Center

    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…

  17. ASSESSMENT OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYLETHER (PBDE) MIXTURE, IN THE EDSP MALE PUBERTAL PROTOCOL

    EPA Science Inventory

    ASSESSMENT OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYL ETHER (PBDE) MIXTURE, IN THE EDSP MALE PUBERTAL PROTOCOL. T.E. Stoker1, J. Ferrell1, J.M. Hedge2, K. M. Crofton2, R.L. Cooper1 and S.C. Laws1. 1 Reprod. Tox. Div., 2 Neurotox. Div., NHEERL, ORD, USEPA, RTP, NC.

    P...

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

    EPA Science Inventory

    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...

  19. ABILITY OF THE MALE RAT PUBERTAL ASSAY TO DETECT ENVIRONMENTAL CHEMICALS THAT ALTER THYROID HORMONE HOMEOSTASIS

    EPA Science Inventory

    ABILITY OF THE MALE RAT PUBERTAL ASSAY TO DETECT ENVIRONMENTAL CHEMICALS THAT ALTER THYROID HORMONE HOMEOSTASIS

    Stoker, Tammy E.1; Laws, Susan C.1; Ferrell, Janet M.1; Cooper, Ralph L.1.

    Endocrinology Branch, RTD, NHEERL, ORD, U.S. EPA, RTP, NC, 27711.

    The...

  20. The Effects of Pubertal Timing and School Transition on Preadolescents' Well-Being

    ERIC Educational Resources Information Center

    Seifert, Tim; Schulz, Henry

    2007-01-01

    Previous research has indicated that pubertal development and the transition from middle or elementary school to junior high may present problems for some preadolescents. The effects of these transitions on achievement, psychological well-being, and social relations were examined using data from the National Longitudinal Survey of Children and…

  1. The Impact of Pubertal and Social Events upon Girls' Problem Behavior.

    ERIC Educational Resources Information Center

    Brooks-Gunn, J.; And Others

    This study examined whether problem behavior in early adolescent girls was associated with pubertal processes and other life events and whether social support and positive relationships buffered the adolescent from possible negative effects of biological and social events. White girls (N=150) between the ages of 10 and 13 years completed the Youth…

  2. Pubertal Development, Choice of Friends, and Smoking Initiation among Adolescent Males

    ERIC Educational Resources Information Center

    Drapela, Laurie A.; Gebelt, Janet L.; McRee, Nick

    2006-01-01

    Prior research has indicated that pubertal development and peer associations are important determinants of adolescent smoking behavior. However, more remains to be learned about "why" these variables matter or how they may be related to one another in ways that lead to the initiation of smoking. Using contractual data from the National…

  3. Pubertal Timing, Sexual Behaviour and Self-Reported Depression in Middle Adolescence.

    ERIC Educational Resources Information Center

    Kaltiala-Heino, Riittakerttu; Kosunen, Elisa; Rimpela, Matti

    2003-01-01

    Study analyzed associations between pubertal timing, sexual activity, and self-reported depression in sample of girls and boys aged 14-16. Among girls, self-reported depression was associated with early puberty and intimate sexual relationship. Among boys, depression was associated with every early and late puberty and experience of intercourse.…

  4. Off-Time Pubertal Timing Predicts Physiological Reactivity to Postpuberty Interpersonal Stress

    ERIC Educational Resources Information Center

    Smith, Anne Emilie; Powers, Sally I.

    2009-01-01

    We investigated associations between retrospectively assessed timing of pubertal development, interpersonal interactions, and hypothalamic-pituitary-adrenal axis reactivity to an interpersonal stress task in 110 young adult women. Participants provided salivary cortisol samples at points prior and subsequent to a video-taped conflict discussion…

  5. Effects of altered food intake during pubertal development in male and female Wistar rats

    EPA Science Inventory

    The U.S.EPA is currently validating assays that will be used in a Tier I Screening Battery to detect endocrine disrupting chemicals. A primary concern with the Protocols for the Assessment of Pubertal Development and Thyroid Function in Juvenile Male and Female Rats is that a non...

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

    ERIC Educational Resources Information Center

    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…

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

    EPA Science Inventory

    Effects of dibutyl phthalate in male rabbits following in utero, adolescent, or post-pubertal exposure
    Ty T. Higuchi1, Jennifer S. Palmer1, L. Earl Gray Jr2., and D. N. Rao Veeramachaneni1
    1Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort

  8. The Role of Pubertal Timing in What Adolescent Boys Do Online

    ERIC Educational Resources Information Center

    Skoog, Therese; Stattin, Hakan; Kerr, Margaret

    2009-01-01

    The aim of this study was to investigate associations between pubertal timing and boys' Internet use, particularly their viewing of pornography. We used a sample comprising of 97 boys in grade 8 (M age, 14.22 years) from two schools in a medium-sized Swedish town. This age should be optimal for differentiating early, on-time, and later-maturing…

  9. Associations between Early Life Stress, Child Maltreatment, and Pubertal Development among Girls in Foster Care

    ERIC Educational Resources Information Center

    Mendle, Jane; Leve, Leslie D.; Van Ryzin, Mark; Natsuaki, Misaki N.; Ge, Xiaojia

    2011-01-01

    The present study investigated pubertal development in girls with maltreatment histories (N=100), assessed at 4 time points over 2 years, beginning in the spring of their final year of elementary school. This sample is unique in that participants were subject to an unusual level of environmental risk early in life and resided in foster care at the…

  10. Relationship Between Timing of Peak Height Velocity and Pubertal Staging in Boys and Girls

    PubMed Central

    Granados, Andrea; Gebremariam, Achamyeleh; Lee, Joyce M.

    2015-01-01

    Growth and pubertal development are important health markers. We used the data of a longitudinal growth study on a contemporary sample of US youth to examine the relationship between peak height velocity (PHV) and Tanner staging. We observed a substantial variability in the timing of PHV across Tanner stages, which is an important consideration for clinicians when assessing growth. PMID:26831559

  11. IMPACT OF BODY WEIGHT CHANGE ON THE EDSTAC TIER 1 MALE AND FEMALE PUBERTAL PROTOCOLS

    EPA Science Inventory

    IMPACT OF BODY WEIGHT CHANGE ON THE EDSTAC TIER I MALE AND FEMALE PUBERTAL PROTOCOLS. R.L. Cooper, T.E. Stoker, K. McElroy, J. Ferrell, K. Leffler, K. Bremser and S.C. Laws. Endocrinology Branch, Reproductive Toxicology Division, NHEERL, ORD, USEPA, RTP, NC. Sponsor: R.J. Kavl...

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

    ERIC Educational Resources Information Center

    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…

  13. Genetic and Environmental Influences on Pubertal Timing: Results from Two National Sibling Studies

    ERIC Educational Resources Information Center

    Ge, Xiaojia; Natsuaki, Misaki N.; Neiderhiser, Jenae M.; Reiss, David

    2007-01-01

    This study examined genetic and environmental effects on individual variation in pubertal timing using two national samples of siblings from the Nonshared Environment of Adolescent Development (NEAD) and the National Longitudinal Study of Adolescent Health (Add Health). In each sample, female and male siblings with different degrees of genetic…

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

    ERIC Educational Resources Information Center

    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…

  15. Cortical porosity is higher in boys compared with girls at the distal radius and distal tibia during pubertal growth: an HR-pQCT study.

    PubMed

    Nishiyama, Kyle K; Macdonald, Heather M; Moore, Sarah A; Fung, Tak; Boyd, Steven K; McKay, Heather A

    2012-02-01

    The aim of this study was to determine the sex- and maturity-related differences in bone microstructure and estimated bone strength at the distal radius and distal tibia in children and adolescents. We used high-resolution pQCT to measure standard morphological parameters in addition to cortical porosity (Ct.Po) and estimated bone strength by finite element analysis. Participants ranged in age from 9 to 22 years (n = 212 girls and n = 186 boys) who were scanned annually for either one (11%) or two (89%) years at the radius and for one (15%), two (39%), or three (46%) years at the tibia. Participants were grouped by the method of Tanner into prepubertal, early pubertal, peripubertal, and postpubertal groups. At the radius, peri- and postpubertal girls had higher cortical density (Ct.BMD; 9.4% and 7.4%, respectively) and lower Ct.Po (-118% and -56%, respectively) compared with peri- and postpubertal boys (all p < 0.001). Peri- and postpubertal boys had higher trabecular bone volume ratios (p < 0.001) and larger cortical cross-sectional areas (p < 0.05, p < 0.001) when compared with girls. Based upon the load-to-strength ratio (failure load/estimated fall force), boys had lower risk of fracture than girls at every stage except during early puberty. Trends at the tibia were similar to the radius with differences between boys and girls in Ct.Po (p < 0.01) and failure load (p < 0.01) at early puberty. Across pubertal groups, within sex, the most mature girls and boys had higher Ct.BMD and lower Ct.Po than their less mature peers (prepuberty) at both the radius and tibia. Girls in early, peri-, and postpubertal groups and boys in peri- and postpubertal groups had higher estimates of bone strength compared with their same-sex prepubertal peers (p < 0.001). These results provide insight into the sex- and maturity-related differences in bone microstructure and estimated bone strength.

  16. Secondary analysis of APPLE study suggests atorvastatin may reduce atherosclerosis progression in pubertal lupus patients with higher C reactive protein

    PubMed Central

    Ardoin, Stacy P; Schanberg, Laura Eve; Sandborg, Christy I; Barnhart, Huiman X; Evans, Greg W; Yow, Eric; Mieszkalski, Kelly L; Ilowite, Norman T; Eberhard, Anne; Imundo, Lisa F; Kimura, Yuki; Levy, Deborah; von Scheven, Emily; Silverman, Earl; Bowyer, Suzanne L; Punaro, L; Singer, Nora G; Sherry, David D; McCurdy, Deborah K; Klein-Gitelman, Marissa; Wallace, Carol; Silver, Richard M; Wagner-Weiner, Linda; Higgins, Gloria C; Brunner, Hermine I; Jung, Lawrence; Soep, Jennifer B; Reed, Ann M; Thompson, Susan D

    2014-01-01

    Objective Participants in the Atherosclerosis Prevention in Paediatric Lupus Erythematosus (APPLE) trial were randomised to placebo or atorvastatin for 36 months. The primary endpoint, reduced carotid intima medial thickness (CIMT) progression, was not met but atorvastatin-treated participants showed a trend of slower CIMT progression. Post-hoc analyses were performed to assess subgroup benefit from atorvastatin therapy. Methods Subgroups were prespecified and defined by age (> or ≤15.5 years), systemic lupus erythematosus (SLE) duration (> or ≤24 months), pubertal status (Tanner score ≥4 as post-pubertal or <4 as pre-pubertal), low density lipoprotein cholesterol (LDL) (≥ or <110 mg/dl) and high-sensitivity C reactive protein (hsCRP) (≥ or <1.5 mg/l). A combined subgroup (post-pubertal and hsCRP≥1.5 mg/l) was compared to all others. Longitudinal linear mixed-effects models were developed using 12 CIMT and other secondary APPLE outcomes (lipids, hsCRP, disease activity and damage, and quality of life). Three way interaction effects were assessed for models. Results Significant interaction effects with trends of less CIMT progression in atorvastatin-treated participants were observed in pubertal (3 CIMT segments), high hsCRP (2 CIMT segments), and the combined high hsCRP and pubertal group (5 CIMT segments). No significant treatment effect trends were observed across subgroups defined by age, SLE duration, LDL for CIMT or other outcome measures. Conclusions Pubertal status and higher hsCRP were linked to lower CIMT progression in atorvastatin-treated subjects, with most consistent decreases in CIMT progression in the combined pubertal and high hsCRP group. While secondary analyses must be interpreted cautiously, results suggest further research is needed to determine whether pubertal lupus patients with high CRP benefit from statin therapy. ClinicalTrials.gov identifier NCT00065806. PMID:23436914

  17. Dietary soy effects on mammary gland development during the pubertal transition in nonhuman primates

    PubMed Central

    Dewi, Fitriya N.; Wood, Charles E.; Lees, Cynthia J.; Willson, Cynthia J.; Register, Thomas C.; Tooze, Janet A.; Franke, Adrian A.; Cline, J. Mark

    2013-01-01

    While epidemiologic studies suggest that soy intake early in life may reduce breast cancer risk, there are also concerns that exposure to soy isoflavones during childhood may alter pubertal development and hormonal profiles. Here, we assessed the effect of a high-soy diet on pubertal breast development, sex hormones, and growth in a nonhuman primate model. Pubertal female cynomolgus monkeys were randomized to receive a diet modeled on a typical North American diet with one of two protein sources for ~4.5 years: i) casein/lactalbumin (CL, n=12, as control) or ii) soy protein isolate with a human equivalent dose of 120 mg/day isoflavones (SOY, n=17), which is comparable to approximately four servings of soy foods. Pubertal exposure to the SOY diet did not alter onset of menarche, indicators of growth and pubertal progression, or circulating estradiol and progesterone concentrations. Greater endometrial area was seen in the SOY group on the first of 4 postmenarchal ultrasound measurements (P<0.05). There was a subtle effect of diet on breast differentiation whereby the SOY group showed higher numbers of differentiated large-sized lobular units and a lower proportion with immature ducts following menarche (P<0.05). Numbers of small lobules and terminal end buds and mammary epithelial cell proliferation did not differ by diet. Expression of progesterone receptor was lower in immature lobules of soy-fed animals (P<0.05). Our findings suggest that consumption of soy starting before menarche may result in modest effects consistent with a more differentiated breast phenotype in adulthood. PMID:23771522

  18. Outcome analysis of aromatase inhibitor therapy to increase adult height in males with predicted short adult stature and/or rapid pubertal progress: a retrospective chart review

    PubMed Central

    Shams, Kim; Cameo, Tamara; Fennoy, Ilene; Hassoun, Abeer A.; Lerner, Shulamit E.; Aranoff, Gaya S.; Sopher, Aviva B.; Yang, Christine; McMahon, Donald J.; Oberfield, Sharon E.

    2015-01-01

    Background Aromatase inhibitors (AIs) have been used off-label to increase adult height in short adolescent males. Studies have shown that AIs increase the predicted adult height (PAH) while delaying bone age (BA) maturation. We sought to determine whether AI therapy increases PAH in boys with short stature or rapid pubertal progression, and to evaluate any untoward effects. Methods The charts of 27 boys with BA ≥ 13 and short stature [height ≥ 2 standard deviation (SD) below the mean or ≥ 2 SD below mid-parental target height (MPTH)] or rapid pubertal progress, treated with anastrozole were reviewed. Outcome measures included anthropomorphic, hormonal, and metabolic data. Results The AI therapy averaged 21 months (range 14–30 months) for all, with Rx group 1 receiving < 18 months therapy (n = 7) and Rx group 2 receiving 18–30 months therapy (n = 20). Post-therapy, in Rx group 1 and all subjects, there was no significant change in the PAH, height SDS, or BA/chronological age (CA). In Rx group 2, there was a small, nonsignificant increase in PAH, no change in height SDS, and a small decrease in BA/CA. Post-therapy PAH was different from MPTH in all and in both Rx groups 1 and 2, p < 0.02. Eight of them achieved near-final height, averaging 6.73 ± 1.40 cm less than MPTH and 1.91 ± 0.86 cm less than the pre-therapy PAH. Post-therapy, the initially decreased estradiol did not persist but mildly increased testosterone and decreased high-density lipoprotein were noted, as was an increase in hematocrit, and decrease in growth velocity. Conclusions We suggest that although bone age progression may be slightly delayed with longer duration of therapy, an overall short-term AI therapy does not lead to a final height that is greater than the predicted pre-therapy height. PMID:24756052

  19. Evaluation of Hydroxyatrazine in the Endocrine Disruptor Screening and Testing Program’s Male and Female Pubertal Protocols.

    EPA Science Inventory

    Evaluation of Hydroxyatrazine in the Endocrine Disruptor Screening and Testing Program’s Male and Female Pubertal Protocols. ABSTRACT Two critical components of the validation of any in vivo screening assay are to demonstrate sensitivity (ability to detect weak endocrine ...

  20. The diagnostic performance of dental maturity for identification of the circumpubertal growth phases: a meta-analysis.

    PubMed

    Perinetti, Giuseppe; Westphalen, Graziela H; Biasotto, Matteo; Salgarello, Stefano; Contardo, Luca

    2013-05-23

    The present meta-analysis initially evaluates the reliability of dental maturation in the identification of the circumpubertal growth phases, essentially for determining treatment timing in orthodontics. A literature survey was performed using the Medline, LILACS and SciELO databases, and the Cochrane Library (2000 to 2011). Studies of the correlation between dental and cervical vertebral maturation methods were considered. The mandibular canine, the first and second premolars, and the second molar were investigated. After the selection, six articles qualified for the final analysis. The overall correlation coefficients were all significant, ranging from 0.57 to 0.73. Five of these studies suggested the use of dental maturation as an indicator of the growth phase. However, the diagnostic performance analysis uncovered limited reliability only for the identification of the pre-pubertal growth phase. The determination of dental maturity for the assessment of treatment timing in orthodontics is not recommended.

  1. In vitro development of secondary follicles from pre-pubertal and adult goats cultured in two-dimensional or three-dimensional systems.

    PubMed

    Silva, G M; Rossetto, R; Chaves, R N; Duarte, A B G; Araújo, V R; Feltrin, C; Bernuci, M P; Anselmo-Franci, J A; Xu, M; Woodruff, T K; Campello, C C; Figueiredo, J R

    2015-08-01

    The aim of this study was to evaluate the influence of two-dimensional (2D) and three-dimensional (3D) alginate culture systems on in vitro development of pre-antral caprine follicles. In addition, the influence of the reproductive age of the ovary donor on the in vitro culture success was investigated. Pre-antral follicles from pre-pubertal or adult goats were isolated and cultured directly on a plastic surface (2D) or encapsulated in an alginate-based matrix (3D). After 18 days, the oocytes underwent in vitro maturation (IVM) and in vitro fertilization (IVF) to produce embryos. The 3D system showed higher rates of follicle survival, lower rates of oocyte extrusion, and a greater number of recovered oocytes for IVM and IVF (P < 0.05). Only pre-antral follicles from adult animals produced MII oocytes and embryos. The estradiol concentrations increased from day 2 to day 12 of culture in all groups tested (P < 0.05). Conversely, progesterone concentrations were lower in 3D-cultured follicles than in 2D-cultured follicles, with differences on days 2 and 6 of culture (P < 0.05). We provide compelling evidence that a 2D or 3D alginate in vitro culture system offers a promising approach to achieving full in vitro development of caprine pre-antral follicles to produce mature oocytes that are capable of fertilization and viable embryos.

  2. A longitudinal study of body dissatisfaction and pubertal timing in an ethnically diverse adolescent sample.

    PubMed

    de Guzman, Natalie S; Nishina, Adrienne

    2014-01-01

    In a 7-year study, adolescents' body dissatisfaction (N=1370) was examined across four high school years as a function of pubertal development (perceived timing relative to peers and self-reported physical changes measured during Grades 6-10) in the context of the high school transition. Boys and girls who, during early high school, perceived themselves to be late relative to peers were at risk for body dissatisfaction across the high school years. Boys who were late in pubertal development reported more body dissatisfaction in early high school than on-time boys, but then decreased over time. African-American girls reported less body dissatisfaction across the high school years relative to other girls. Asian girls reported more dissatisfaction in early high school than African-American, Latina, and Multiethnic girls, and increased over time. Results highlight the importance of considering late development within context as a risk factor in body dissatisfaction research. PMID:24331829

  3. The role of mutations affecting gonadotrophin secretion and action in disorders of pubertal development.

    PubMed

    Huhtaniemi, Ilpo T

    2002-03-01

    A number of mutations that disturb the development and function of the hypothalamic-pituitary-gonadal (HPG) axis and cause disturbances in pubertal development are known today. These mutations have effects at all levels of the HPG axis, from the migration of gonadotrophin releasing hormone (GnRH) neurones from the nasal cavity to the hypothalamus, GnRH secretion, GnRH action, pituitary gonadotroph differentiation, gonadotrophin synthesis and secretion, right through to gonadotrophin action. Most of the mutations are inactivating, thus causing hypogonadism and arrest or delay of pubertal development. One exception is the activating mutations of the LH receptor, which causes the male-limited gonadotrophin-independent precocious puberty. The human mutations and animal models with disrupted function of orthologous genes have clarified the molecular pathogenesis of hypogonadism and disturbances of pubertal development. The correct diagnosis of these disorders using molecular biological techniques is now possible. This allows the selection of specific treatments and correct counselling of the patients and their families.

  4. Fat feeding of rats during pubertal growth leads to neuroendocrine alterations in adulthood.

    PubMed

    Boukouvalas, George; Gerozissis, Kyriaki; Kitraki, Efthimia

    2010-01-01

    Juvenile obesity is a rising epidemic due largely to consumption of caloric dense, fat-enriched foods. Nevertheless, literature on fat-induced neuroendocrine and metabolic disturbances during adolescence, preceding obesity, is limited. This study aimed to examine early events induced by a fat diet (45% calories from saturated fat) in male rats fed the diet during the pre- and post-pubertal period. The neuroendocrine endpoints studied were the levels of circulating leptin, insulin and corticosterone, as well as their receptors in the hypothalamus and hippocampus. Hormonal levels were determined by radioimmunoassay and receptors' levels by western blot analysis. Leptinemia was increased in pubertal rats and in adult rats fed the fat diet from weaning to adulthood, but not in those fed from puberty to adulthood. Modifications in the developmental pattern from puberty to adulthood were observed for most of the brain receptors studied. In adult animals fed the fat diet from weaning onwards, the levels of leptin receptors in the hypothalamus and glucocorticoid receptors in the hippocampus were decreased compared to chow-fed controls. Switching from fat to normal chow at puberty onset restored the diet-induced alterations on circulating leptin, but not on its hypothalamic receptors. These data suggest that when a fat-enriched diet, resembling those consumed by many teenagers, provided in rats during pubertal growth, it can longitudinally influence the actions of leptin and corticosterone in the brain. The observed alterations at a preobese state may constitute early signs of the disturbed energy balance toward overweight and obesity.

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

    PubMed

    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.

  6. The influence of sex steroids on structural brain maturation in adolescence.

    PubMed

    Koolschijn, P Cédric M P; Peper, Jiska S; Crone, Eveline A

    2014-01-01

    Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls. PMID:24416184

  7. The influence of sex steroids on structural brain maturation in adolescence.

    PubMed

    Koolschijn, P Cédric M P; Peper, Jiska S; Crone, Eveline A

    2014-01-01

    Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls.

  8. The Influence of Sex Steroids on Structural Brain Maturation in Adolescence

    PubMed Central

    Koolschijn, P. Cédric M. P.; Peper, Jiska S.; Crone, Eveline A.

    2014-01-01

    Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8–25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls. PMID:24416184

  9. Protein and micronutrient supplementation in complementing pubertal growth.

    PubMed

    Jacob, J A; Nair, M K C

    2012-01-01

    For several reasons, adolescence is considered as a nutritionally critical period of life. The dramatic increase in physical growth and development puts greater pressure on the need for nutrients, as it is during this period when adolescents experience a weight gain equivalent to 65% of their weight at the beginning of the period or 40% of their final weight, and a height gain equivalent to 15% of their adult height. The requirement of some of the nutrients is as high as, or higher in adolescents than in any other age groups. Moreover, adolescence is a time where the life-style and food habits are influenced by socio-cultural factors resulting in an imbalance in nutrient intake and nutrient inadequacy can result in delayed sexual maturation and can arrest or slow linear growth. With the increasing prevalence of hidden malnutrition among Indian children, adolescence can be the second opportunity to catch up growth and cover the deficits suffered during childhood and to meet the demands of physical and cognitive growth and development, provide adequate stores of energy for illnesses and pregnancy, and prevent adult onset of nutrition-related diseases. Adolescents should be recognized as a priority target group as an integral part of health promotion and optimal nutrition through balanced diet and nutrient supplementation should be promoted in conjunction with healthy eating habits and physical activity.

  10. Data Product Maturity

    Atmospheric Science Data Center

    2013-03-25

    ... document, maturity levels are provided separately for each scientific data set (SDS) included with the data files. The data product ... indiscriminate use of these data products as the basis for research findings, journal publications, and/or presentations.   ...

  11. Variations in the Pattern of Pubertal Changes in Boys

    PubMed Central

    Marshall, W. A.; Tanner, J. M.

    1970-01-01

    Mixed longitudinal data on the physical changes at puberty in 228 normal boys are presented together with normal standards for stages of genital and pubic hair development. The genitalia began to develop between the ages 9½ years and 13½ years in 95% of boys (mean = 11.6 ± 0.09) and reached maturity at ages varying between 13 and 17 (mean = 14.9 ± 1.10). The age at which pubic hair first appeared was not accurately determined, but its development through the later stages was studied. It reached the equivalent of an adult female distribution at a mean age of 15.2 ± 0.01 years. On average the genitalia reached the adult stage 3.0 years after they first began to develop; but some boys completed this development in as little as 1.8 years while others took as much as 4.7 years. Some boys complete the whole process in less time than others take to go from Stage G2 to Stage G3. The genitalia begin to develop before pubic hair is visible in photographs in practically all boys. The 41 boys in whom it could be studied reached their maximum rate of growth (peak height velocity) at a mean age of 14.1 ± 0.14 years. Very few boys (about 5%) reached peak height velocity before their genitalia were in Stage 4 and over 20% did not do so until their genitalia were adult. Peak height velocity is reached, on the average, nearly 2 years later in boys than in girls, but the boys' genitalia begin to develop only about 6 months later than the girls' breasts. Pubic hair appears about 1½ years later in boys than in girls. ImagesFig. 1Fig. 2 PMID:5440182

  12. 7 CFR 1427.7 - Maturity of loans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the producer notice of such acceleration at least 30 days in advance of the accelerated maturity date. (b) If the loan is not repaid by the loan maturity date, title to the cotton shall vest in CCC the... than the last day of the 9th calendar month following the month in which the note and...

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

    PubMed

    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.

  14. Mechanics of bacteriophage maturation.

    PubMed

    Roos, Wouter H; Gertsman, Ilya; May, Eric R; Brooks, Charles L; Johnson, John E; Wuite, Gijs J L

    2012-02-14

    Capsid maturation with large-scale subunit reorganization occurs in virtually all viruses that use a motor to package nucleic acid into preformed particles. A variety of ensemble studies indicate that the particles gain greater stability during this process, however, it is unknown which material properties of the fragile procapsids change. Using Atomic Force Microscopy-based nano-indentation, we study the development of the mechanical properties during maturation of bacteriophage HK97, a λ-like phage of which the maturation-induced morphological changes are well described. We show that mechanical stabilization and strengthening occurs in three independent ways: (i) an increase of the Young's modulus, (ii) a strong rise of the capsid's ultimate strength, and (iii) a growth of the resistance against material fatigue. The Young's modulus of immature and mature capsids, as determined from thin shell theory, fit with the values calculated using a new multiscale simulation approach. This multiscale calculation shows that the increase in Young's modulus isn't dependent on the crosslinking between capsomers. In contrast, the ultimate strength of the capsids does increase even when a limited number of cross-links are formed while full crosslinking appears to protect the shell against material fatigue. Compared to phage λ, the covalent crosslinking at the icosahedral and quasi threefold axes of HK97 yields a mechanically more robust particle than the addition of the gpD protein during maturation of phage λ. These results corroborate the expected increase in capsid stability and strength during maturation, however in an unexpected intricate way, underlining the complex structure of these self-assembling nanocontainers.

  15. Phagosome maturation: aging gracefully.

    PubMed Central

    Vieira, Otilia V; Botelho, Roberto J; Grinstein, Sergio

    2002-01-01

    Foreign particles and apoptotic bodies are eliminated from the body by phagocytic leucocytes. The initial stage of the elimination process is the internalization of the particles into a plasma membrane-derived vacuole known as the phagosome. Such nascent phagosomes, however, lack the ability to kill pathogens or to degrade the ingested targets. These properties are acquired during the course of phagosomal maturation, a complex sequence of reactions that result in drastic remodelling of the phagosomal membrane and contents. The determinants and consequences of the fusion and fission reactions that underlie phagosomal maturation are the topic of this review. PMID:12061891

  16. Impact of pubertal development and physical activity on heart rate variability in overweight and obese children in Taiwan.

    PubMed

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

    2012-08-01

    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 system function in overweight and obese children and the concurrent effects of their physical activity. Eighty-four overweight or obese children and 87 normal weighted controls were recruited. Autonomic nervous system function was studied by measuring heart rate variability. Results showed that the overweight/obese children had significantly lower heart rate variability. Overweight/obese children in puberty had significantly lower heart rate variability which was positively correlated with their physical activity levels. In conclusion, overweight/obesity adversely affects the autonomic nervous system function of children especially during their pubertal development. Overweight/obese children should be encouraged to engage in physical activities during puberty to improve their autonomic nervous system function.

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

    PubMed Central

    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

  18. Comparison of growth and pubertal progression in wild type female rats with different bedding types

    PubMed Central

    Kang, Byung Ho; Kim, Shin-Hee; Jung, Kyung A; Kim, So Youn; Chung, Sung-Hoon; Park, Young Shil; Yoon, Kyung Lim

    2015-01-01

    Purpose Endocrine-disrupting chemicals interfere with the endocrine system and therefore affect growth and pubertal progression. The study aim was to compare the growth and pubertal progression in wild-type female rats with different bedding types. Methods Twenty 5-week-old female wild-type Sprague Dawley rats were randomly assigned to two groups with different bedding types: one group received wood shaving bedding, while a second group received corncob bedding. We determined crown-rump length and body weight as anthropometric measurements and assessed the serum growth hormone (GH) and estradiol levels. The gh1 mRNA expression levels were compared using quantitative real time transcription polymerase chain reaction. The estrous cycle was evaluated by vaginal smear. Results The anthropometric measurements were not significantly different between the two groups. The mean relative expression of the gh1 gene was lower in the corncob bedding group than that in the wood shaving group (P=0.768). Meanwhile serum GH and estradiol were increased in the wood shaving bedding group; however this difference was not statistically significant. The time to first estrus and the length of the estrous cycle were increased in the corncob bedding group; the proportion of normal estrous cycles was also decreased. These findings indicate irregularities in the estrous cycle. Conclusion Endocrine-disrupting chemicals in corncob bedding might be associated with time to first estrus and length of the estrous cycle. Therefore, the type of bedding should be considered as a factor affecting pubertal progression in rodents. PMID:25883928

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

    PubMed

    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.

  20. DNA Methylation Patterns in Rat Mammary Carcinomas Induced by Pre- and Post-Pubertal Irradiation

    PubMed Central

    Takabatake, Masaru; Blyth, Benjamin J.; Daino, Kazuhiro; Imaoka, Tatsuhiko; Nishimura, Mayumi; Fukushi, Masahiro; Shimada, Yoshiya

    2016-01-01

    Several lines of evidence indicate one’s age at exposure to radiation strongly modifies the risk of radiation-induced breast cancer. We previously reported that rat mammary carcinomas induced by pre- and post-pubertal irradiation have distinct gene expression patterns, but the changes underlying these differences have not yet been characterized. The aim of this investigation was to see if differences in CpG DNA methylation were responsible for the differences in gene expression between age at exposure groups observed in our previous study. DNA was obtained from the mammary carcinomas arising in female Sprague-Dawley rats that were either untreated or irradiated (γ-rays, 2 Gy) during the pre- or post-pubertal period (3 or 7 weeks old). The DNA methylation was analyzed using CpG island microarrays and the results compared to the gene expression data from the original study. Global DNA hypomethylation in tumors was accompanied by gene-specific hypermethylation, and occasionally, by unique tumor-specific patterns. We identified methylation-regulated gene expression candidates that distinguished the pre- and post-pubertal irradiation tumors, but these represented only 2 percent of the differentially expressed genes, suggesting that methylation is not a major or primary mechanism underlying the phenotypes. Functional analysis revealed that the candidate methylation-regulated genes were enriched for stem cell differentiation roles, which may be important in mammary cancer development and worth further investigation. However, the heterogeneity of human breast cancer means that the interpretation of molecular and phenotypic differences should be cautious, and take into account the co-variates such as hormone receptor status and cell-of-origin that may influence the associations. PMID:27711132

  1. Evaluation of hydroxyatrazine in the endocrine disruptor screening and testing program's male and female pubertal protocols.

    PubMed

    Stoker, Tammy E; Hallinger, Daniel R; Seely, John C; Zorrilla, Leah M

    2013-10-01

    Two critical components of the validation of any in vivo screening assay are to demonstrate sensitivity and specificity. Although the Endocrine Disruptor Screening Program's Tier 1 Male and Female Pubertal Protocols have been shown to be sensitive assays for the detection of weak endocrine disrupting chemicals (EDCs), there are concerns that the assays lack specificity for EDC effects when a chemical induces systemic toxicity. A lack of specificity, or the ability to correctly identify an inactive or "negative" chemical, would increase the probability of identifying false positives. Here, we orally exposed rats to hydroxyatrazine (OH-ATR), a biotransformation by-product of the chlorotriazine herbicides that produced nephrotoxicity following a 13-week dietary exposure. Based on a previous study in our laboratory, males were dosed with 11.4 to 183.4 mg/kg OH-ATR and females were dosed with 45.75 to 183.4 mg/kg OH-ATR. Following exposure in both sexes, there was a dose-response increase in mean kidney weights and the incidence and severity of kidney lesions. These lesions included the deposition of mineralized renal tubule concretions, hydronephrosis, renal tubule dilatation, and pyelonephritis. However, no differences in body weight, liver weight, or reproductive tissue weights, reproductive or thyroid histology, hormone concentrations or the age of pubertal onset were observed. Therefore, the results demonstrate that the endpoints included in the pubertal assay are useful for nonendocrine (systemic) effects that define an no observable effect level (NOEL) or lowest observable effect level (LOEL) and provide one example where an impact on kidney function does not alter any of the endocrine-specific endpoints of the assay.

  2. Sex matters during adolescence: testosterone-related cortical thickness maturation differs between boys and girls.

    PubMed

    Bramen, Jennifer E; Hranilovich, Jennifer A; Dahl, Ronald E; Chen, Jessie; Rosso, Carly; Forbes, Erika E; Dinov, Ivo D; Worthman, Carol M; Sowell, Elizabeth R

    2012-01-01

    Age-related changes in cortical thickness have been observed during adolescence, including thinning in frontal and parietal cortices, and thickening in the lateral temporal lobes. Studies have shown sex differences in hormone-related brain maturation when boys and girls are age-matched, however, because girls mature 1-2 years earlier than boys, these sex differences could be confounded by pubertal maturation. To address puberty effects directly, this study assessed sex differences in testosterone-related cortical maturation by studying 85 boys and girls in a narrow age range and matched on sexual maturity. We expected that testosterone-by-sex interactions on cortical thickness would be observed in brain regions known from the animal literature to be high in androgen receptors. We found sex differences in associations between circulating testosterone and thickness in left inferior parietal lobule, middle temporal gyrus, calcarine sulcus, and right lingual gyrus, all regions known to be high in androgen receptors. Visual areas increased with testosterone in boys, but decreased in girls. All other regions were more impacted by testosterone levels in girls than boys. The regional pattern of sex-by-testosterone interactions may have implications for understanding sex differences in behavior and adolescent-onset neuropsychiatric disorders.

  3. Pubertal and postpubertal cadmium exposure differentially affects the hypothalamic-pituitary-testicular axis function in the rat.

    PubMed

    Lafuente, A; Márquez, N; Pérez-Lorenzo, M; Pazo, D; Esquifino, A I

    2000-10-01

    The effects of administration of cadmium on levels of hormones along the hypothalamic-pituitary-testicular axis were studied in rats. Male rats were treated subcutaneously from days 30 to 60 (pubertal rats) or from days 60 to 90 of life (postpubertal rats), with cadmium chloride (CdCl2) at a dose of 0.5 or 1 mg/kg, every 4 days in an alternate schedule, starting from the lower dose. Age-matched control rats received 0.3 m of saline subcutaneously every 4 days. The levels of norepinephrine (NE) increased on cadmium exposure in pubertal rats in all hypothalamic areas studied, but decreased in the median eminence. In contrast, in postpubertal rats the levels of NE only did not decrease in the posterior hypothalamus. Serotonin (5-HT) concentration in pubertal and postpubertal rats decreased in all hypothalamic regions, while serotonin turnover (measured by the ratio 5-hydroxyindolacetic acid/serotonin [5-HIAA/5-HT]) increased in the anterior hypothalamus. The serotonin metabolism was also increased in the median eminence in the pubertal and in the posterior hypothalamus in the postpubertal rats. Plasma levels of luteinizing hormone (LH) were not modified by cadmium in both age groups, but follicle stimulating hormone (FSH) levels decreased in postpubertal rats, but was not altered in pubertal rats. Plasma levels of testosterone increased in pubertal rats but decreased in postpubertal rats. Cadmium accumulation increased in the hypothalamus and testes in all the cadmium-treated animals, whereas in the pituitary accumulation of cadmium was found only in postpubertal rats. These data suggest that cadmium exerts age-dependent effects on the hypothalamic-pituitary-testicular axis function, and a disruption of the regulatory mechanisms of the hypothalamic-pituitary-gonadal axis emerges.

  4. Semi-longitudinal Study of the Mcnamara Cephalometric Triangle in Class II and Class III Subjects Grouped by Cervical Vertebrae Maturation Stage.

    PubMed

    Arriola-Guillén, Luis E; Fitzcarrald, Fernando D; Flores-Mir, Carlos

    2015-12-01

    The aim was to compare the McNamara cephalometric triangle values in untreated normodivergent Class II and Class III malocclusion subjects of Latin American origin grouped by cervical vertebrae maturation stage to an untreated Class I malocclusion normodivergent control group. The study was conducted on a sample of 610 pretreatment lateral cephalograms (250 male, 360 female), examined and grouped according to their anteroposterior skeletal relationship (Class I, II or III), cervical vertebrae maturation stage (Pre Pubertal Peak P1 = CS1 and CS2, Pubertal Peak P2= CS3 and CS4, and Post Pubertal Peak P3 = CS5 and CS6) and sex. Co-A, Co-Gn and ENA-Me were measured in each lateral cephalogram. ANOVA and Tukey HSD post-hoc tests were performed to determine differences between the groups. The results showed that in males, the greatest maxillary and mandibular dimensional increases occurred during the P3 stage (CS5 to CS6), while in females, they occurred in the P2 stage (CS3 to CS4). The Co-A and Co-Gn showed significant differences between the malocclusion classes (p<0.05). The maxillary lengths in Class II subjects and the mandibular lengths in Class III subjects were already higher at the beginning of the period evaluated (P1). A worsening trend for the Class II and III malocclusions was identified during the period evaluated. Finally, changes in the McNamara cephalometric triangle values were markedly different in the three normodivergent skeletal malocclusion classes. In these Latin American subjects the pubertal growth spurt occurred at different times with respect to the Caucasian and Asian norms.

  5. Risking it for Love: Romantic Relationships and Early Pubertal Development Confer Risk for later Disruptive Behavior Disorders in African-American Girls Receiving Psychiatric Care

    PubMed Central

    Rodriguez, Erin M.; Nichols, Sara; Emerson, Erin; Donenberg, Geri R.

    2014-01-01

    Disruptive behavior problems (DBP) represent a growing concern for young women (e.g., Snyder & Sickmund, 2006), but gender-specific investigations have been traditionally underrepresented in this area. The purpose of this study is to examine the associations among gender-relevant risk factors for DBP among 217 African American girls in psychiatric care. African American girls, 12–16 years old (M=14.6; SD=1.2), and their primary female caregivers (N=254) were recruited from outpatient mental health clinics and reported on girls’ DBP, heterosexual dating experiences (romantic and sexual), peer relationships, pubertal development, and self-silencing at baseline, 6-, and 12-months. Structural Equation Modeling examined evidence for full versus mediated (via self-silencing) models and the structural relationships (direct and indirect) among key study variables. Results suggest that the full model was a significantly better fit than the mediated model as indicated by a Chi-squared difference test (p < .01). In the full model, direct effects of greater romantic dating experiences and lower quality peer relationships at baseline predicted DBP at 12-months. Sexual dating experiences were more strongly linked with DBP at 12-months for early maturing compared to average or later maturing girls. Indirect effects analyses suggested that girls’ suppression of relational needs, assessed through a measure of self-silencing, explained the association between peer relationships and DBP. Findings highlight the importance of the relational context for girls’ DBP, with treatment implications supporting relationship-based models of care, early intervention, and skill building around negotiating needs with peers and partners. PMID:24748499

  6. Risking it for love: romantic relationships and early pubertal development confer risk for later disruptive behavior disorders in African-American girls receiving psychiatric care.

    PubMed

    Javdani, Shabnam; Rodriguez, Erin M; Nichols, Sara R; Emerson, Erin; Donenberg, Geri R

    2014-11-01

    Disruptive behavior problems (DBP) represent a growing concern for young women (e.g., Snyder and Sickmund, 2006), but gender-specific investigations have been traditionally underrepresented in this area. The purpose of this study is to examine the associations among gender-relevant risk factors for DBP among 217 African American girls in psychiatric care. African American girls, 12-16 years old (M = 14.6; SD = 1.2), and their primary female caregivers (N = 254) were recruited from outpatient mental health clinics and reported on girls' DBP, heterosexual dating experiences (romantic and sexual), peer relationships, pubertal development, and self-silencing at baseline, 6-, and 12 months. Structural Equation Modeling examined evidence for full versus mediated (via self-silencing) models and the structural relationships (direct and indirect) among key study variables. Results suggest that the full model was a significantly better fit than the mediated model as indicated by a Chi-squared difference test (p < 0.01). In the full model, direct effects of greater romantic dating experiences and lower quality peer relationships at baseline predicted DBP at 12 months. Sexual dating experiences were more strongly linked with DBP at 12 months for early maturing compared to average or later maturing girls. Indirect effects analyses suggested that girls' suppression of relational needs, assessed through a measure of self-silencing, explained the association between peer relationships and DBP. Findings highlight the importance of the relational context for girls' DBP, with treatment implications supporting relationship-based models of care, early intervention, and skill building around negotiating needs with peers and partners. PMID:24748499

  7. Absence of pubertal gonadotropin secretion in girls with McCune-Albright syndrome.

    PubMed

    Foster, C M; Ross, J L; Shawker, T; Pescovitz, O H; Loriaux, D L; Cutler, G B; Comite, F

    1984-06-01

    Precocious puberty in girls with McCune-Albright syndrome has been attributed in some cases to early activation of the hypothalamic-pituitary-gonadal axis and in other cases to sex steroid secretion by apparently autonomous ovarian cysts. We evaluated serum gonadotropins and sex steroids in six girls (aged 1-9 yr) with McCune-Albright syndrome. The children had Tanner stage II-IV pubertal development. In five patients, nocturnal gonadotropin concentrations and the gonadotropin response to LHRH were within the normal range for prepubertal children. Thus, the precocious puberty in these patients could not be explained by activation of the hypothalamic-pituitary-ovarian axis. One child had high amplitude nocturnal pulses of serum LH and a LH-predominant response to LHRH. She was the oldest of the six girls and had a bone age of 13.5 yr which is within the range in which hypothalamic-pituitary-ovarian activation normally occurs. The children all had ovarian enlargement and ovarian cysts determined by ultrasound. It appears that precocious puberty in McCune-Albright syndrome may result from ovarian estrogen secretion in the absence of normal pubertal activation of the hypothalamic-pituitary-ovarian axis.

  8. Association between CYP19A1 genotype and pubertal sagittal jaw growth

    PubMed Central

    He, Shushu; Hartsfield, James K.; Guo, Yujiao; Cao, Yang; Wang, Si; Chen, Song

    2016-01-01

    Introduction Sagittal jaw growth is influenced during puberty by a ratio of androgens and estrogens. The CYP19A1 (formerly CYP19) gene encodes the cytochrome P450 enzyme aromatase (estrogen synthetase), which converts testosterone to estrogen. Genetic variations including single nucleotide polymorphisms might regulate CYP19A1 gene expression or the function of the aromatase protein and thus influence sagittal jaw growth. Methods The annual sagittal jaw growth in 92 pubertal orthodontic patients was determined by using pretreatment and posttreatment cephalometric radiographs. Single nucleotide polymorphisms rs2470144 and rs2445761 were genotyped and haplotypes constructed. Associations between genotypes or haplotypes and the annual sagittal growth were estimated by using JMP (version 9.0; SAS Institute, Cary, NC). Results Two single nucleotide polymorphisms were significantly associated with average differences in annual sagittal jaw growth in boys. Haplotype analysis demonstrated that haplotypes Trs2470144Trs2445761 and Crs2470144Trs2445761 had significant effects on annual sagittal maxillary growth and on mandibular growth in boys. No association was found in girls. Conclusions A quantitative trait locus that influences male pubertal sagittal jaw growth might exist in the CYP19A1 gene, and single nucleotide polymorphisms rs2470144 and rs2445761 might be inside this quantitative trait locus or be linked to it. PMID:23116507

  9. Bone mass in schoolchildren in Brazil: the effect of racial miscegenation, pubertal stage, and socioeconomic differences.

    PubMed

    Ribeiro, Roberto Regis; Guerra-Junior, Gil; de Azevedo Barros-Filho, Antonio

    2009-01-01

    The purpose of this study was to evaluate bone mass by phalanges ultrasound in healthy white and black schoolchildren in relationship to socioeconomic level, pubertal stage, and body composition. Included were 1,356 healthy schoolchildren aged from 6 to 11 years from different socioeconomic levels and both genders; all were placed into white and black groups. Weight, height, body mass index, fat percentage, fat mass, and lean mass were evaluated by anthropometric methods, and AD-SoS bone quantity and UBPI bone quality were evaluated using a third-generation IGEA phalanges DBM Sonic BP ultrasound. Data were compared using the Mann-Whitney, chi-squared, correlation coefficient, and analyses of multiple linear regression statistical tests with 5% significance. Black schoolchildren predominated in the low socioeconomic levels. Higher values of weight and height for black boys and girls were observed in the lean mass in relation to white children of the same gender and age. An increasing variation in the bone quantity mean was observed from 6 to 11 years of age and with pubertal stage for both genders and skin color. The white schoolchildren presented higher values of bone quantity and quality in relation to the black children. The anthropometric, gender, and socioeconomic level variables explained only 16 and 11% of the variability of bone quantity and quality, respectively. As such, the present study, carried out with healthy black and white Brazilian schoolchildren, demonstrated higher bone mass, as evaluated by ultrasound, in white than in black schoolchildren.

  10. Quantitative ultrasound bone measurements in pre-pubertal children with type 1 diabetes.

    PubMed

    Chobot, Agata P; Haffke, Anna; Polanska, Joanna; Halaba, Zenon P; Deja, Grazyna; Jarosz-Chobot, Przemyslawa; Pluskiewicz, Wojciech

    2012-07-01

    This case-control study aimed to assess bone status in children with type 1 diabetes mellitus (T1DM). Fifty-seven pre-pubertal patients (37 boys, aged 7.9 ± 2.5 years, T1DM duration 3.1 ± 1.6 years) and 171 age-matched healthy controls (111 boys) were studied. Quantitative ultrasound (QUS) was used to measure amplitude dependent speed of sound (Ad-SoS) at hand phalanges (expressed as standard deviation score [SDS]). Anthropometric and disease-related data (including mean HbA(1c) from whole T1DM duration [T], last year [Y], examination day [D]) were collected. Mean Ad-SoS SDS in patients -0.13 ± 1.32 (95% confidence interval [CI] -0.48, 0.22) was similar to that of controls. Subgroups discriminated according to HbA(1c) D, Y and T (cut-off 7.0%) did not differ regarding analyzed parameters. In patients, Ad-SoS SDS was comparable for both genders. Multivariable stepwise regression analysis showed significant negative influence of diabetes duration on Ad-SoS SDS. QUS findings in pre-pubertal children with T1DM do not differ from those in healthy children. Disease duration seems to affect negatively Ad-SoS SDS. However, independent prospective studies are needed to elucidate the true associations.

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

    PubMed

    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.

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

    PubMed

    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.

  13. Oral testosterone undecanoate in the management of delayed puberty in boys: pharmacokinetics and effects on sexual maturation and growth.

    PubMed

    Butler, G E; Sellar, R E; Walker, R F; Hendry, M; Kelnar, C J; Wu, F C

    1992-07-01

    adult height remained unchanged. No side effects were observed. Our preliminary data suggest that oral TU is a well accepted, effective, and safe treatment for the initiation of male puberty without disproportionate skeletal maturation. Continued pubertal advance was evident after cessation of treatment in all patients.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1619029

  14. Effect of pubertal status and number of estrous cycles prior to the breeding season on pregnancy rate in beef heifers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three experiments were conducted to evaluate whether pubertal status prior to breeding influences pregnancy rate in beef heifers. Records were collected at West Central Research and Extension Center, North Platte, NE from 2002 to 2011 (Exp. 1; n = 1,005) and Gudmundsen Sandhills Laboratory, Whitman,...

  15. The Moderating Effects of Pubertal Timing on the Longitudinal Associations between Parent-Child Relationship Quality and Adolescent Substance Use

    ERIC Educational Resources Information Center

    Shelton, Katherine H.; Van Den Bree, Marianne B. M.

    2010-01-01

    This prospective, longitudinal study investigated the moderating role of pubertal timing on reciprocal links between adolescent appraisals of parent-child relationship quality and girls' (N = 1,335) and boys' (N = 1,203) cigarette and alcohol use across a 12-month period. Reciprocal effects were found between parent-child relations and on-time…

  16. THE EFFECTS OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYL EITHER MIXTURE, ON FEMALE PUBERTAL DEVELOPMENT AND THYROID FUNCTION

    EPA Science Inventory

    THE EFFECTS OF DE-71, A COMMERICAL POLYBROMINATED DIPHENYL ETHER MIXTURE, ON FEMALE PUBERTAL DEVELOPMENT AND THYROID FUNCTION. S.C. Laws1, J. M. Ferrell1, J. M Hedge2, K. M. Crofton2, R.L. Cooper1, and T.E. Stoker1. 1Reprod. Tox. Div., 2Neurotox. Div., NHEERL, ORD, USEPA, R...

  17. ASSESSMENT OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYL ETHER (PBDE) MIXTURE, IN THE EDSP MALE AND FEMALE PUBERTAL PROTOCOLS

    EPA Science Inventory

    DE-71, a commercial mixture, was used to test the sensitivity of the female and male pubertal protocol to detect thyroid active chemicals. These protocols are being evaluated for the U.S. EPA's Endocrine Disruptor Screening Program as part of a Tier I Screening Battery. To exa...

  18. Pubertal timing is an independent predictor of central adiposity in young adult males: the Gothenburg osteoporosis and obesity determinants study.

    PubMed

    Kindblom, Jenny M; Lorentzon, Mattias; Norjavaara, Ensio; Lönn, Lars; Brandberg, John; Angelhed, Jan-Erik; Hellqvist, Asa; Nilsson, Staffan; Ohlsson, Claes

    2006-11-01

    The role of puberty and normal variations in pubertal timing for the development of obesity in men is unclear. The aim of the current study was to investigate the impact of pubertal timing and prepubertal BMI (kg/m(2)) for young adult BMI and fat mass distribution. Detailed growth charts from birth to age 18-20 years were retrieved for the men participating in the population-based Gothenburg Osteoporosis and Obesity Determinants study. Age at peak height velocity (PHV) and BMI at age 10 years were estimated for 579 subjects, and PHV was used as an assessment of pubertal timing. The fat mass characterization and distribution were analyzed using dual X-ray absorptiometry and peripheral as well as abdominal computed tomography at age 18.9 +/- 0.5 years. We demonstrate that age at PHV is an independent negative predictor of young adult BMI and whole-body fat mass. Interestingly, age at PHV is an independent negative predictor of central, but not peripheral, fat mass. In contrast, BMI at 10 years of age predicts both central and peripheral subcutaneous fat mass. In conclusion, we demonstrate that early pubertal onset specifically predicts a central fat mass distribution, while a predominantly subcutaneous obese phenotype is strongly predicted by a high prepubertal BMI.

  19. Effects of Pubertal Timing on Communication Behaviors and Stress Reactivity in Young Women during Conflict Discussions with Their Mothers

    ERIC Educational Resources Information Center

    Weichold, Karina; Buttig, Sabine; Silbereisen, Rainer K.

    2008-01-01

    Individuation, a process whereby adolescents gain autonomy from their parents while maintaining emotional relatedness, is displayed by characteristic styles of verbal exchanges. Negotiating this developmental transition is often stressful for adolescents and their parents. This study deals with the association between pubertal timing,…

  20. The Interactive Role of Anxiety Sensitivity and Pubertal Status in Predicting Anxious Responding to Bodily Sensations among Adolescents

    ERIC Educational Resources Information Center

    Leen-Feldner, Ellen W.; Reardon, Laura E.; McKee, Laura G.; Feldner, Matthew T.; Babson, Kimberly A.; Zvolensky, Michael J. J.

    2006-01-01

    The present study examined the interaction between pubertal status and anxiety sensitivity (AS) in predicting anxious and fearful responding to a three-minute voluntary hyperventilation challenge among 124 (57 females) adolescents between the ages of 12 and 17 years (Mage = 15.04; SD = 1.49). As predicted, after controlling for baseline anxiety,…

  1. Self-perceptions of pubertal timing and patterns of peer group activities and dating behavior among heterosexual adolescent girls.

    PubMed

    Carter, Rona; Williams, Sandra

    2016-02-01

    This study identified patterns of past and concurrent peer group and dating behavior in a sample of adolescent girls (N = 511; aged 17-19 years; 49% White). Peer group activities and dating behaviors were classified as occurring in either early (ages 10-13 years), middle (ages 14-16 years), or late (ages 17-19 years) adolescence according to the age at which each participant indicated the activity/behavior was first experienced. Latent class analysis identified four latent classes: Early Interactions/Early Daters (15%), Early Interactions/Late Daters (17%), Early Interactions/Middle Daters (33%) and Middle Interactions/Middle Daters (35%). Class membership was associated with girl's perceived pubertal timing. Compared to Early Interactions/Early Daters, girls in the Early Interactions/Late Daters class reported higher levels of pubertal timing, indicating greater perception that their pubertal development was late relative to peers. Late perceived pubertal timing is potentially relevant for dating but not necessarily other mixed- and cross-sex peer interactions. PMID:26775189

  2. The Effect of Pubertal and Psychosocial Timing on Adolescents' Alcohol Use: What Role Does Alcohol-Specific Parenting Play?

    ERIC Educational Resources Information Center

    Schelleman-Offermans, Karen; Knibbe, Ronald A.; Engels, Rutger C. M. E.; Burk, William J.

    2011-01-01

    In scientific literature, early pubertal timing emerges as a risk factor of adolescents' drinking, whereas alcohol-specific rules (the degree to which parents permit their children to consume alcohol in various situations) showed to protect against adolescents' drinking. This study investigated whether alcohol-specific rules mediate and/or…

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

    ERIC Educational Resources Information Center

    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…

  4. A Socioanalytic Model of Maturity

    ERIC Educational Resources Information Center

    Hogan, Robert; Roberts, Brent W.

    2004-01-01

    K0 describes a point of view on maturity that departs from earlier treatments in two ways. First, it rejects the popular assumption from humanistic psychology that maturity is a function of self-actualization and stipulates that maturity is related to certain performance capacities--namely, the ability to form lasting relationships and to achieve…

  5. VARIABLES ASSOCIATED WITH VOCATIONAL MATURITY.

    ERIC Educational Resources Information Center

    REICHMAN, WALTER

    EVIDENCE ABOUT THE CONSTRUCT VALIDITY OF PRESUMED VOCATIONAL MATURITY FACTOR SCORES WAS OBTAINED BY STUDYING THE RELATIONSHIP BETWEEN FACTORS OF VOCATIONAL MATURITY AND A GROUP OF CONCURRENT VARIABLES DEEMED RELEVANT TO VOCATIONAL MATURITY. THESE VARIABLES WERE CLASSIFIED INTO FIVE GROUPS--FAMILY SOCIOECONOMIC STATUS, ABILITY AND ACHIEVEMENT,…

  6. Pubertal Expression of α4βδ GABAA Receptors Reduces Seizure-Like Discharges in CA1 Hippocampus.

    PubMed

    Yang, Lie; Shen, Hui; Merlin, Lisa R; Smith, Sheryl S

    2016-01-01

    More than half of children with epilepsy outgrow their seizures, yet the underlying mechanism is unknown. GABAergic inhibition increases at puberty in female mice due to expression of extrasynaptic α4βδ GABAA receptors (GABARs). Therefore, we tested the role of these receptors in regulating seizure-like discharges in CA1 hippocampus using a high K(+) (8.5 mM) seizure model. Spontaneous field potentials were recorded from hippocampus of pre-pubertal (~28-32 PND) and pubertal (~35-44 PND) female wild-type or α4-/- mice. The coastline length, a measure of burst intensity, was assessed. 8.5 mM K(+) induced seizure-like discharges in over 60% of pre-pubertal slices, but only in 7% of pubertal slices, where the coastline length was reduced by 70% (P = 0.04). However, the pubertal decrease in seizure-like discharges was not seen in the α4-/-, implicating α4βδ GABARs as the cause of the decreased seizure-like activity during puberty. Administration of THIP or DS2, to selectively increase α4βδ current, reduced activity in 8.5 mM K(+) at puberty, while blockade of α5-GABARs had no effect. GABAergic current was depolarizing but inhibitory in 8.5 mM K(+), suggesting a mechanism for the effects of α4βδ and α5-GABARs, which exhibit different polarity-dependent desensitization. These data suggest that α4βδ GABARs are anti-convulsant during adolescence. PMID:27561815

  7. Pubertal Expression of α4βδ GABAA Receptors Reduces Seizure-Like Discharges in CA1 Hippocampus.

    PubMed

    Yang, Lie; Shen, Hui; Merlin, Lisa R; Smith, Sheryl S

    2016-01-01

    More than half of children with epilepsy outgrow their seizures, yet the underlying mechanism is unknown. GABAergic inhibition increases at puberty in female mice due to expression of extrasynaptic α4βδ GABAA receptors (GABARs). Therefore, we tested the role of these receptors in regulating seizure-like discharges in CA1 hippocampus using a high K(+) (8.5 mM) seizure model. Spontaneous field potentials were recorded from hippocampus of pre-pubertal (~28-32 PND) and pubertal (~35-44 PND) female wild-type or α4-/- mice. The coastline length, a measure of burst intensity, was assessed. 8.5 mM K(+) induced seizure-like discharges in over 60% of pre-pubertal slices, but only in 7% of pubertal slices, where the coastline length was reduced by 70% (P = 0.04). However, the pubertal decrease in seizure-like discharges was not seen in the α4-/-, implicating α4βδ GABARs as the cause of the decreased seizure-like activity during puberty. Administration of THIP or DS2, to selectively increase α4βδ current, reduced activity in 8.5 mM K(+) at puberty, while blockade of α5-GABARs had no effect. GABAergic current was depolarizing but inhibitory in 8.5 mM K(+), suggesting a mechanism for the effects of α4βδ and α5-GABARs, which exhibit different polarity-dependent desensitization. These data suggest that α4βδ GABARs are anti-convulsant during adolescence.

  8. Pubertal Expression of α4βδ GABAA Receptors Reduces Seizure-Like Discharges in CA1 Hippocampus

    PubMed Central

    Yang, Lie; Shen, Hui; Merlin, Lisa R.; Smith, Sheryl S.

    2016-01-01

    More than half of children with epilepsy outgrow their seizures, yet the underlying mechanism is unknown. GABAergic inhibition increases at puberty in female mice due to expression of extrasynaptic α4βδ GABAA receptors (GABARs). Therefore, we tested the role of these receptors in regulating seizure-like discharges in CA1 hippocampus using a high K+ (8.5 mM) seizure model. Spontaneous field potentials were recorded from hippocampus of pre-pubertal (~28–32 PND) and pubertal (~35–44 PND) female wild-type or α4−/− mice. The coastline length, a measure of burst intensity, was assessed. 8.5 mM K+ induced seizure-like discharges in over 60% of pre-pubertal slices, but only in 7% of pubertal slices, where the coastline length was reduced by 70% (P = 0.04). However, the pubertal decrease in seizure-like discharges was not seen in the α4−/−, implicating α4βδ GABARs as the cause of the decreased seizure-like activity during puberty. Administration of THIP or DS2, to selectively increase α4βδ current, reduced activity in 8.5 mM K+ at puberty, while blockade of α5-GABARs had no effect. GABAergic current was depolarizing but inhibitory in 8.5 mM K+, suggesting a mechanism for the effects of α4βδ and α5-GABARs, which exhibit different polarity-dependent desensitization. These data suggest that α4βδ GABARs are anti-convulsant during adolescence. PMID:27561815

  9. Estrogen and progesterone receptor expression in neuroendocrine and related neurons of the pubertal female monkey hypothalamus.

    PubMed

    Goldsmith, P C; Boggan, J E; Thind, K K

    1997-05-01

    Expression of hypothalamic estrogen receptors (ER) and progesterone receptors (PR) is barely evident in prepubertal monkeys but is prominent in adults. To investigate whether adult patterns of ER and PR expression are established in mid-pubertal female cynomolgus monkeys, we labeled neuroendocrine (NEU) neurons by microinjection of retrograde tracer into the median eminence, and then identified ER and PR by specific immunostaining in separate sets of hypothalamic sections. ER and PR appeared in the cytoplasm and nuclei of cells identified exclusively as neurons, and retrograde tracer remained clearly visible in the cytoplasm of NEU neurons after immunostaining. Numbers of NEU and related neurons expressing ER or PR were quantified in principal hypothalamic regions. In the supraoptic nucleus, almost all neurons analyzed (n = 580) contained ER (94%) with many also NEU (73% ER + NEU), while lesser amounts of the neurons examined (n = 214) expressed PR (75%) and were NEU (53% PR + NEU). In the paraventricular nucleus, most of the neurons analyzed (n = 302) contained ER (90% ER; 54% ER + NEU), but few of the neurons studied (n = 269) contained PR (34% PR; 19% PR + NEU). In the periventricular zone, nearly all neurons examined (n = 795) contained ER (95% ER; 48% ER + NEU), but fewer of those studied (n = 298) exhibited PR (79% PR; 47% PR + NEU). In the arcuate-periventricular zone, all neurons examined (n = 542) contained ER (100%) but few were NEU (4% ER + NEU), while nearly all neurons studied (n = 418) contained PR (95%), some of which were NEU (21% PR + NEU). Neurons expressing ER were also prevalent in areas without NEU labeling, including the diagonal band of Broca, medial preoptic area, and mammillary bodies, but were less common in the septum and dorsomedial hypothalamus. Likewise, neuronal PR expression was seen frequently in the mammillary bodies, but occurred less often in the diagonal band of Broca, medial preoptic area, and dorsomedial hypothalamus. Neurons

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

    PubMed

    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

  11. Advanced Stage, Increased Lactate Dehydrogenase, and Primary Site, but Not Adolescent Age (≥ 15 Years), Are Associated With an Increased Risk of Treatment Failure in Children and Adolescents With Mature B-Cell Non-Hodgkin's Lymphoma: Results of the FAB LMB 96 Study

    PubMed Central

    Cairo, Mitchell S.; Sposto, Richard; Gerrard, Mary; Auperin, Anne; Goldman, Stanton C.; Harrison, Lauren; Pinkerton, Ross; Raphael, Martine; McCarthy, Keith; Perkins, Sherrie L.; Patte, Catherine

    2012-01-01

    Purpose Adolescents (age 15 to 21 years) compared with younger children with mature B-cell non-Hodgkin's lymphoma (NHL) have been historically considered to have an inferior prognosis. We therefore analyzed the impact of age and other diagnostic factors on the risk of treatment failure in children and adolescents treated on the French-American-British Mature B-Cell Lymphoma 96 (FAB LMB 96) trial. Patients and Methods Patients were divided by risk: group A (limited), group B (intermediate), and group C (advanced), as previously described. Prognostic factors analyzed for event-free survival (EFS) included age (< 15 v ≥ 15 years), stage (I/II v III/IV), primary site, lactate dehydrogenase (LDH), bone marrow/CNS (BM/CNS) involvement, and histology (diffuse large B-cell lymphoma v mediastinal B-cell lymphoma v Burkitt lymphoma or Burkitt-like lymphoma). Results The 3-year EFS for the whole cohort was 88% ± 1%. Age was not associated as a risk factor for increased treatment failure in either univariate analysis (P = .15) or multivariate analysis (P = .58). Increased LDH (≥ 2 × upper limit of normal [ULN] v < 2 × ULN), primary site, and BM-positive/CNS-positive disease were all independent risk factors associated with a significant increase in treatment failure rate (relative risk, 2.0; P < .001, P < .012, and P < .001, respectively). Conclusion LDH level at diagnosis, mediastinal disease, and combined BM-positive/CNS-positive involvement are independent risk factors in children with mature B-cell NHL. Future studies should be developed to identify specific therapeutic strategies (immunotherapy) to overcome these risk factors and to identify the biologic basis associated with these prognostic factors in children with mature B-cell NHL. PMID:22215753

  12. Influence of pubertal stage on local sweating patterns of girls exercising in the heat.

    PubMed

    Wilk, Boguslaw; Pender, Nola; Volterman, Kim; Bar-Or, Oded; Timmons, Brian W

    2013-05-01

    The influence of puberty on sweating patterns of girls exercising in the heat is not known. Nine- to 17-year-old girls, representing 4 stages of breast development: T1 (n = 21); T2 (n = 22); T3 (n = 25); and T4 (n = 22), cycled for 20 min at 60% in 35 °C. The population density of heat activated sweat glands was higher in T1 vs T3 and T4 and in T2 vs T4. Sweat drop area was lower in T1 vs T3 and in T1 vs T4, T2 vs T4 and T3 vs T4. The proportion of skin covered by sweat was lower in T1 vs T4. Sweating patterns of girls exercising in the heat are influenced by pubertal stage.

  13. Effects of stress after hurricanes katrina and rita on pubertal disorders in children.

    PubMed

    Ponnapakkam, Adharsh; Gensure, Robert

    2008-01-01

    Hurricanes Katrina and Rita caused widespread damage that resulted in increased stress levels for families living in the New Orleans area. This study examined the relationship between this stress and the onset of puberty in children by conducting a retrospective chart review of patients referred before and after the storm to a pediatric endocrine practice in New Orleans. The total number of new patients referred and the incidence of diagnoses that are unlikely to be affected by stress (ie, thyroid disease and premature adrenarche) were essentially unchanged. On the other hand, the incidence of central precocious puberty decreased by 52% after the storm, while the incidence of pubertal delay increased by 9% in the post storm period. This study thus provides evidence that stress delays the onset of puberty in children.

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

    PubMed Central

    Gaurav, Kumar; Chandra, Gautam; Neelam, Kumari; Kumar, Sanjeet; Singla, Harish; Yadav, Sanjay Kumar

    2015-01-01

    Introduction Fibroadenomas are benign neoplasms usually arising between the ages of 15–25 years. Approximately 0.4% fibroadenomas arise in juvenile age group. Usually the diagnosis is straightforward by clinical examination and FNAC. But sometimes rapid growth and giant size may pose difficulty in clinical approach. Case presentation In this paper we are presenting a rare case of giant juvenile fibroadenoma in a 10 years old girl which was diagnosed by FNAC and treated by excision. Diagnosis was confirmed by histopathology. Discussion Giant juvenile fibroadenomas are over 5 cm in diameter and tend to show rapid growth mimicking a carcinoma. But histological features are similar to smaller fibroadenomas and can be enucleated. 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. PMID:26433926

  15. Propolis inhibits osteoclast maturation.

    PubMed

    Pileggi, Roberta; Antony, Kathryn; Johnson, Kristie; Zuo, Jian; Shannon Holliday, L

    2009-12-01

    Propolis, a natural product produced by the honey bee, has been successfully used in medicine as an anti-inflammatory and antimicrobial agent. Traumatic injuries to the teeth, especially avulsion injuries, present a challenging situation for the clinician because of post-treatment complications, such as inflammatory and/or replacement resorption. Agents that reduce osteoclast numbers and activity may be useful in the treatment of traumatic injuries to the teeth. In this study, we evaluated propolis as an anti-resorptive agent. Calcitriol-stimulated mouse marrow cultures, which contain both osteoclasts and osteoblasts, were exposed to the ethanol extracts of propolis or vehicle control and stained for tartrate-resistant acid phosphatase (TRAP)-activity to identify osteoclasts. A significant, dose-dependent reduction in multinuclear TRAP+ cells was demonstrated, although the propolis treatment accommodated cell growth and survival (P < 0.05). Propolis also reduced the formation of actin rings in pure cultures of RAW 264.7 osteoclast-like cells, suggesting that it exerts direct actions on osteoclast maturation. In summary, our data suggest that propolis inhibits late stages of osteoclast maturation including fusion of osteoclasts precursors to form giant cells and formation of actin rings. This supports the hypothesis that it may prove useful as a medicament to reduce resorption associated with traumatic injuries to the teeth. PMID:19843135

  16. Influence of age, body weight and body condition score before mating start date on the pubertal rate of maiden Holstein-Friesian heifers and implications for subsequent cow performance and profitability.

    PubMed

    Archbold, H; Shalloo, L; Kennedy, E; Pierce, K M; Buckley, F

    2012-07-01

    The aim of this study was to assess the influence of age, body weight (BW) and body condition score (BCS) of maiden Holstein-Friesian heifers before mating start date (MSD) on the rate of puberty, subsequent production and longevity and their implications with regard to farm profitability. Data were available on 871 Holstein-Friesian heifers from 48 herds. BW was recorded electronically and BCS was recorded by a single operator on a scale of 1 to 5. Heifer age was calculated as the number of days from birth to the day of visit. All of the independent variables of interest were grouped into three or four categories. Three age categories (thirtiles), four BW categories (quartiles) and four BCS categories (≤ 2.75, 3.00, 3.25 and ≥ 3.50) were formed. Heifers with an identifiable corpus lutuem (CL) in the presence or absence of large follicles and peri-ovulatory signs and with a plasma progesterone (P4) concentration ≥ 1 ng/ml were classified as pubertal. In addition, heifers without an identifiable CL in the presence or absence of large follicles and peri-ovulatory signs but with a P4 concentration ≥ 1 ng/ml were also classified as pubertal. Age, BW and BCS at MSD were all found to be significantly associated with pubertal rate (P < 0.05). Age was shown to have no practical implications on subsequent cow performance. BW at MSD was favourably associated with subsequent calving date (P < 0.05), subsequent cow BW (P < 0.001) and potential (305 days) milk fat plus protein yield (P < 0.001). BCS at MSD was found to be favourably associated with milk fat plus protein yield potential (P < 0.05) and BCS (P < 0.001) during lactation. The economic analysis undertaken indicated that larger, well-grown heifers will be more profitable because of superior production potential, all else being equal. However, because of the finding of poorer reproductive efficiency in heifers grown to more than 343 kg at MSD, heifers at ∼330 kg at MSD are deemed optimal. This will correspond

  17. Behavioral effects of pubertal anabolic androgenic steroid exposure in male rats with low serotonin.

    PubMed

    Keleta, Yonas B; Lumia, Augustus R; Anderson, George M; McGinnis, Marilyn Y

    2007-02-01

    The goal of this study was to assess the interactive effects of chronic anabolic androgenic steroid (AAS) exposure and brain serotonin (5-hydroxytryptamine, 5-HT) depletion on behavior of pubertal male rats. Serotonin was depleted beginning on postnatal day 26 with parachlorophenylalanine (PCPA 100 mg/kg, every other day); controls received saline. At puberty (P40), half the PCPA-treated rats and half the saline-treated rats began treatment with testosterone (T, 5 mg/kg, 5 days/week). Behavioral measures included locomotion, irritability, copulation, partner preference, and aggression. Animals were tested for aggression in their home cage, both with and without physical provocation (mild tail pinch). Brain levels of 5-HT and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA), were determined using HPLC. PCPA significantly and substantially depleted 5-HT and 5-HIAA in all brain regions examined. Chronic T treatment significantly decreased 5-HT and 5-HIAA in certain brain areas, but to a much lesser extent than PCPA. Chronic exposure to PCPA alone significantly decreased locomotor activity and increased irritability but had no effect on sexual behavior, partner preference, or aggression. T alone had no effect on locomotion, irritability, or sexual behavior but increased partner preference and aggression. The most striking effect of combining T+PCPA was a significant increase in attack frequency as well as a significant decrease in the latency to attack, particularly following physical provocation. Based on these data, it can be speculated that pubertal AAS users with low central 5-HT may be especially prone to exhibit aggressive behavior. PMID:17194457

  18. Pubertal development in HIV-infected African children on first-line antiretroviral therapy

    PubMed Central

    Szubert, Alexander J.; Musiime, Victor; Bwakura-Dangarembizi, Mutsawashe; Nahirya-Ntege, Patricia; Kekitiinwa, Adeodata; Gibb, Diana M.; Nathoo, Kusum; Prendergast, Andrew J.; Walker, A. Sarah

    2015-01-01

    Objectives: To estimate age at attaining Tanner stages in Ugandan/Zimbabwean HIV-infected children initiating antiretroviral therapy (ART) in older childhood and investigate predictors of delayed puberty, particularly age at ART initiation. Design: Observational analysis within a randomized trial. Methods: Tanner staging was assessed every 24 weeks from 10 years of age, menarche every 12 weeks and height every 4–6 weeks. Age at attaining different Tanner stages was estimated using normal interval regression, considering predictors using multivariable regression. Growth was estimated using multilevel models with child-specific intercepts and trajectories. Results: Median age at ART initiation was 9.4 years (inter-quartile range 7.8, 11.3) (n = 582). At the first assessment, the majority (80.2%) were in Tanner stage 1; median follow-up with staging was 2.8 years. There was a strong delaying effect of older age at ART initiation on age at attaining all Tanner stages (P < 0.05) and menarche (P = 0.02); in boys the delaying effect generally weakened with older age. There were additional significant delays associated with greater impairments in pre-ART height-for-age Z-score (P < 0.05) in both sexes and pre-ART BMI-for-age in girls (P < 0.05). There was no evidence that pre-ART immuno-suppression independently delayed puberty or menarche. However, older children/adolescents had significant growth spurts in intermediate Tanner stages, and were still significantly increasing their height when in Tanner stage 5 (P < 0.01). Conclusion: Delaying ART initiation until older childhood substantially delays pubertal development and menarche, independently of immuno-suppression. This highlights that factors other than CD4+, such as pubertal development, need consideration when making decisions about timing of ART initiation in older children. PMID:25710288

  19. The progestin levonorgestrel disrupts gonadotropin expression and sex steroid levels in pubertal roach (Rutilus rutilus).

    PubMed

    Kroupova, H K; Trubiroha, A; Lorenz, C; Contardo-Jara, V; Lutz, I; Grabic, R; Kocour, M; Kloas, W

    2014-09-01

    The aim of the present study was to investigate the effects of the synthetic progestin levonorgestrel (LNG) on the reproductive endocrine system of a teleost fish, the roach (Rutilus rutilus). Pubertal roach were exposed for 28 days in a flow-through system to four concentrations of LNG (3, 31, 312, and 3124 ng/l). Both males and females treated with 3124 ng/l LNG exhibited the upregulated levels of vitellogenin and oestrogen receptor 1 mRNA in the liver. At the same concentration, LNG caused a significant upregulation of the mRNA expression of the gene encoding luteinising hormone β-subunit (lhβ) and the suppression of the mRNA expression of the gene encoding follicle-stimulating hormone β-subunit (fshβ) in the pituitary of both male and female roach. A lower LNG concentration (312 ng/l) suppressed mRNA expression of fshβ in males only. Females treated with 3124 ng/l LNG exhibited significantly lower plasma 11-ketotestosterone (11-KT) and oestradiol (E2) concentrations, whereas their testosterone (T) level was higher compared with the control. Females exposed to 312 ng/l LNG presented significantly lower plasma E2 concentrations. Males exposed to ≥31 ng/l LNG exhibited significantly reduced 11-KT levels. As determined through a histological analysis, the ovaries of females were not affected by LNG exposure, whereas the testes of males exposed to 31 and 312 ng/l LNG exhibited a significantly higher percentage of spermatogonia B compared with the control. The results of the present study demonstrate that LNG disrupts the reproductive system of pubertal roach by affecting the pituitary gonadotropin expression and the sex steroid levels. This disruption was determined to occur in males after exposure to an environmentally relevant concentration (31 ng/l). Moreover, the highest tested concentration of LNG (3124 ng/l) exerted an oestrogenic effect on fish of both sexes. PMID:24893273

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

    PubMed

    Chakraborty, Tandra R; Alicea, Eilliut; Chakraborty, Sanjoy

    2012-01-01

    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 competing with estradiol for binding with estrogen receptors or via the ERK/NK-kappa or ERRγ pathway. This review demonstrates the effects of phytoestrogens, phthalates, and phenols on the development of girls during puberty.

  1. Metabolomics reveals impaired maturation of HDL particles in adolescents with hyperinsulinaemic androgen excess

    PubMed Central

    Samino, Sara; Vinaixa, Maria; Díaz, Marta; Beltran, Antoni; Rodríguez, Miguel A.; Mallol, Roger; Heras, Mercedes; Cabre, Anna; Garcia, Lorena; Canela, Nuria; de Zegher, Francis; Correig, Xavier; Ibáñez, Lourdes; Yanes, Oscar

    2015-01-01

    Hyperinsulinaemic androgen excess (HIAE) in prepubertal and pubertal girls usually precedes a broader pathological phenotype in adulthood that is associated with anovulatory infertility, metabolic syndrome and type 2 diabetes. The metabolic derangements that determine these long-term health risks remain to be clarified. Here we use NMR and MS-based metabolomics to show that serum levels of methionine sulfoxide in HIAE girls are an indicator of the degree of oxidation of methionine-148 residue in apolipoprotein-A1. Oxidation of apo-A1 in methionine-148, in turn, leads to an impaired maturation of high-density lipoproteins (HDL) that is reflected in a decline of large HDL particles. Notably, such metabolic alterations occur in the absence of impaired glucose tolerance, hyperglycemia and hypertriglyceridemia, and were partially restored after 18 months of treatment with a low-dose combination of pioglitazone, metformin and flutamide. PMID:26099471

  2. Advanced Manufacturing Technologies

    NASA Technical Reports Server (NTRS)

    Fikes, John

    2016-01-01

    Advanced Manufacturing Technologies (AMT) is developing and maturing innovative and advanced manufacturing technologies that will enable more capable and lower-cost spacecraft, launch vehicles and infrastructure to enable exploration missions. The technologies will utilize cutting edge materials and emerging capabilities including metallic processes, additive manufacturing, composites, and digital manufacturing. The AMT project supports the National Manufacturing Initiative involving collaboration with other government agencies.

  3. Is the kisspeptin system involved in responses to food restriction in order to preserve reproduction in pubertal male sea bass (Dicentrarchus labrax)?

    PubMed

    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.

  4. A longitudinal study investigating the stability of anthropometry and soccer-specific endurance in pubertal high-level youth soccer players.

    PubMed

    Deprez, Dieter; Buchheit, Martin; Fransen, Job; Pion, Johan; Lenoir, Matthieu; Philippaerts, Renaat M; Vaeyens, Roel

    2015-06-01

    We investigated the evolution and stability of anthropometric and soccer-specific endurance characteristics of 42 high-level, pubertal soccer players with high, average and low yo-yo intermittent recovery test level 1 (YYIR1) baseline performances over two and four years. The rates of improvement were calculated for each performance group, and intra-class correlations were used to verify short- and long-term stability. The main finding was that after two and four years, the magnitudes of the differences at baseline were reduced, although players with high YYIR1 baseline performance still covered the largest distance (e.g., low from 703 m to 2126 m; high from 1503 m to 2434 m over four years). Furthermore, the YYIR1 showed a high stability over two years (ICC = 0.76) and a moderate stability over four years (ICC = 0.59), due to large intra-individual differences in YYIR1 performances over time. Anthropometric measures showed very high stability (ICCs between 0.94 to 0.97) over a two-year period, in comparison with a moderate stability (ICCs between 0.57 and 0.75) over four years. These results confirm the moderate-to-high stability of high-intensity running performance in young soccer players, and suggest that the longer the follow-up, the lower the ability to predict player's future potential in running performance. They also show that with growth and maturation, poor performers might only partially catch up their fitter counterparts between 12 and 16 years. Key pointsYoung, high-level soccer players with a relatively low intermittent-endurance capacity are capable to catch up with their better performing peers after four years.Individual development and improvements of anthropometric and physical characteristics should be considered when evaluating young soccer players. PMID:25983593

  5. A Longitudinal Study Investigating the Stability of Anthropometry and Soccer-Specific Endurance in Pubertal High-Level Youth Soccer Players

    PubMed Central

    Deprez, Dieter; Buchheit, Martin; Fransen, Job; Pion, Johan; Lenoir, Matthieu; Philippaerts, Renaat M.; Vaeyens, Roel

    2015-01-01

    We investigated the evolution and stability of anthropometric and soccer-specific endurance characteristics of 42 high-level, pubertal soccer players with high, average and low yo-yo intermittent recovery test level 1 (YYIR1) baseline performances over two and four years. The rates of improvement were calculated for each performance group, and intra-class correlations were used to verify short- and long-term stability. The main finding was that after two and four years, the magnitudes of the differences at baseline were reduced, although players with high YYIR1 baseline performance still covered the largest distance (e.g., low from 703 m to 2126 m; high from 1503 m to 2434 m over four years). Furthermore, the YYIR1 showed a high stability over two years (ICC = 0.76) and a moderate stability over four years (ICC = 0.59), due to large intra-individual differences in YYIR1 performances over time. Anthropometric measures showed very high stability (ICCs between 0.94 to 0.97) over a two-year period, in comparison with a moderate stability (ICCs between 0.57 and 0.75) over four years. These results confirm the moderate-to-high stability of high-intensity running performance in young soccer players, and suggest that the longer the follow-up, the lower the ability to predict player’s future potential in running performance. They also show that with growth and maturation, poor performers might only partially catch up their fitter counterparts between 12 and 16 years. Key points Young, high-level soccer players with a relatively low intermittent-endurance capacity are capable to catch up with their better performing peers after four years. Individual development and improvements of anthropometric and physical characteristics should be considered when evaluating young soccer players. PMID:25983593

  6. "Bounce at the Bell": a novel program of short bouts of exercise improves proximal femur bone mass in early pubertal children

    PubMed Central

    McKay, H; MacLean, L; Petit, M; MacKelvie-O'Brien, K; Janssen, P; Beck, T; Khan, K

    2005-01-01

    Objectives: To examine the effects of a simple and inexpensive physical activity intervention on change in bone mass and structure in school aged children. Methods: Fifty one children (n = 23 boys and 28 girls; mean age 10.1 years) participated in "Bounce at the Bell" which consisted of 10 counter-movement jumps 3x per day (total ∼3 min/day). Controls were 71 matched children who followed usual school practice. We assessed dietary calcium, physical activity, physical performance, and anthropometry in September and after 8 months of intervention (June). We measured bone mineral content (BMC) and bone area at the lumbar spine, total body, and proximal femur. Proximal femur scans were also analysed for bone geometry and structural strength using the hip structural analysis program. Lean and fat mass (g) were also calculated. Results: Groups were similar at baseline and did not differ in weight, height, total body, lumbar spine, proximal femur, or femoral neck BMC. Control children had a greater increase in adjusted total body BMC (1.4%). Intervention children gained significantly more BMC at the total proximal femur (2%) and the intertrochanteric region (27%). Change in bone structural parameters did not differ between groups. Conclusions: This novel, easily implemented exercise program, took only a few minutes each day and enhanced bone mass at the weight bearing proximal femur in early pubertal children. A large, randomised study of boys and girls should be undertaken powered to test the effectiveness of Bounce at the Bell in children at different stages of maturity, and in boys and girls independently. PMID:16046335

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

    PubMed

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

    2016-05-01

    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 = 2066) 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

  8. Loss of vitamin D receptor signaling from the mammary epithelium or adipose tissue alters pubertal glandular development.

    PubMed

    Johnson, Abby L; Zinser, Glendon M; Waltz, Susan E

    2014-10-15

    Vitamin D₃ receptor (VDR) signaling within the mammary gland regulates various postnatal stages of glandular development, including puberty, pregnancy, involution, and tumorigenesis. Previous studies have shown that vitamin D₃ treatment induces cell-autonomous growth inhibition and differentiation of mammary epithelial cells in culture. Furthermore, mammary adipose tissue serves as a depot for vitamin D₃ storage, and both epithelial cells and adipocytes are capable of bioactivating vitamin D₃. Despite the pervasiveness of VDR in mammary tissue, individual contributions of epithelial cells and adipocytes, as well as the VDR-regulated cross-talk between these two cell types during pubertal mammary development, have yet to be investigated. To assess the cell-type specific effect of VDR signaling during pubertal mammary development, novel mouse models with mammary epithelial- or adipocyte-specific loss of VDR were generated. Interestingly, loss of VDR in either cellular compartment accelerated ductal morphogenesis with increased epithelial cell proliferation and decreased apoptosis within terminal end buds. Conversely, VDR signaling specifically in the mammary epithelium modulated hormone-induced alveolar growth, as ablation of VDR in this cell type resulted in precocious alveolar development. In examining cellular cross-talk ex vivo, we show that ligand-dependent VDR signaling in adipocytes significantly inhibits mammary epithelial cell growth in part through the vitamin D₃-dependent production of the cytokine IL-6. Collectively, these studies delineate independent roles for vitamin D₃-dependent VDR signaling in mammary adipocytes and epithelial cells in controlling pubertal mammary gland development.

  9. Work Maturity Skills Instructor Guide.

    ERIC Educational Resources Information Center

    Lankard, Bettina; And Others

    This teaching guide is a part of those materials developed for the Work Maturity Skills Training Program. (The Work Maturity Skills Training Program is a set of individualized competency-based units that are designed to help participants develop the competencies they need to find and retain jobs.) Following a brief description of the purpose and…

  10. Career Education and Career Maturity.

    ERIC Educational Resources Information Center

    Trebilco, Geoffrey R.

    1984-01-01

    Investigated the relationships between career maturity and career curriculum in 38 Melbourne metropolitan secondary schools (N=2280 students) using an Australian adaption of the Career Development Inventory. Results confirmed that schools with career education programs achieved higher gains in student career maturity. (JAC)

  11. Reproductive organ weights and semen quality of pubertal boars fed dietary fumonisin B1.

    PubMed

    Gbore, F A

    2009-08-01

    Fumonisins, a group of toxic metabolites produced by the genus Fusarium, are known to be consumed by farm animals and are the causative agent or a suspected contributing factor in farm animal diseases. Pigs are particularly susceptible to fumonisins. Reproductive inefficiency is recognized as the most costly limiting constraint to efficient animal production. To account for potential reproductive effects of fumonisin in boars, dietary fumonisin B1 (FB1) was fed to 24 male Large White weanling pigs, 8 to 9 weeks of age. The animals were randomly assigned to four diets containing 5.0, 10.0, 15.0 and 0.2 mg FB1/kg constituting diets 1, 2, 3 and control diet, respectively. After 6 months, semen samples were collected from the pubertal boars and analysed. After the semen collection, all the pubertal boars were killed by decapitation, their reproductive systems dissected and the weights of the testes and epididymides as well as the volumes of the testes recorded. Dietary FB1 did not influence both the relative weights of the testes and epididymides as well as the volumes of the testes. Except for the semen volume and spermatozoa morphological abnormalities, all the semen characteristics studied decreased in a dose-dependent manner and the decrease was statistically significant (P < 0.05). The sperm concentration, total sperm and motile sperm per ejaculate of the animals on diet 3 were 83.3%, 79.1% and 59.6% of the controls, respectively. The dietary FB1 levels influenced the mass activities of the semen, which ranged from very turbulent motion for animals on the control diet to absence of wave motion for those on diet 3. The study revealed that male weanling pigs for breeding should not be exposed to dietary FB1 higher than 5 mg/kg for optimum reproductive performance. The results of this present study suggest that the recommendation of 10 mg/kg by the United States Food and Drug Administration as the maximum level of total dietary fumonisins was above the no

  12. Spontaneous pubertal development in Turner's syndrome. Italian Study Group for Turner's Syndrome.

    PubMed

    Pasquino, A M; Passeri, F; Pucarelli, I; Segni, M; Municchi, G

    1997-06-01

    The incidence of spontaneous puberty in Turner's syndrome is reported to be between 5-10% and, more recently in some series, as high as 20%. In an Italian retrospective multicenter study, of 522 patients older than 12 yr with Turner's syndrome, 84 patients (16, 1%) presented spontaneous pubertal development with menarche that occurred at a chronological age of 13.2 +/- 1.5 yr (mean +/- SD) and a bone age of 12.9 +/- 1.9 yr. Karyotype distribution in the whole group was as follows: 52.1% (272 patients) X-monosomy (45,X), 13.2% (69 patients) mosaicism characterized by X-monosomy and cellular line with no structural abnormalities of the second X, 19.9% (104 patients) mosaicism characterized by X-monosomy and cellular line with structural abnormalities of the second X, and 14.8% (77 patients) structural abnormalities of the second X. Menstrual cycles were still regular in 30 patients at 9.2 +/- 5.0 yr after menarche, 12 developed secondary amenorrhea 1.6 +/- 2.0 yr after menarche, and 19 had irregular menstrual cycles 0.9 +/- 1.8 yr after menarche. As signs of spontaneous puberty developed in 14.0% of X-monosomic patients and in 32.0% of patients with cell lines with more than one X, the presence of the second X seems to have a cardinal influence on the appearance of spontaneous puberty. Spontaneous pregnancy occurred in 3 patients (3.6%). The presence of chromosomal abnormalities and malformations in 2 of 3 pregnancies led us to agree with other investigators in discouraging unassisted pregnancies. Treatment with GH does not seem to exert any influence on either the age of onset or the prevalence of spontaneous pubertal development in Turner's syndrome. The increased percentage of spontaneous menarche is Turner's syndrome reported in the recent literature might be due to increased ascertainment by diligent screening for Turner's syndrome in girls with short stature and mild or no Turner's syndrome stigmata, even though they may be menstruating.

  13. Growth and maturity status of elite British junior tennis players.

    PubMed

    Myburgh, Gillian K; Cumming, Sean P; Coelho E Silva, Manuel; Cooke, Karl; Malina, Robert M

    2016-10-01

    Growth and maturation impact the selection, development and progression of youth athletes. Individual differences in the growth and maturity may afford a performance advantage, clouding coaches and practitioners' perceptions regarding current ability and future potential. This may result in the exclusion of talented, yet less physically gifted athletes. Participants were 91 male (n = 47) and female (n = 44) elite British Junior tennis players, 8-17 years of age (12.5 ± 1.9 years). Height and body mass were measured and compared to growth charts; hand-wrist radiographs were taken. Skeletal age (SA) was estimated with the Fels method and contrasted to chronological age (CA). Mean height and body mass of individual players ranged between the 50th and 90th centiles for age and sex. Females were advanced in SA relative to CA (0.3-0.89 years.) from 8 years. Males were average to delayed in maturation from 8 to 12 years, but advanced in SA from 14 to 16 years (0.75-1.23 years). Individual differences in growth and maturation appear to contribute towards the selection of elite junior tennis players, with a bias towards males and females who are advanced in maturation and comparatively tall and heavy for their age. This has important implications for talent identification and development. PMID:26930031

  14. Growth and maturity status of elite British junior tennis players.

    PubMed

    Myburgh, Gillian K; Cumming, Sean P; Coelho E Silva, Manuel; Cooke, Karl; Malina, Robert M

    2016-10-01

    Growth and maturation impact the selection, development and progression of youth athletes. Individual differences in the growth and maturity may afford a performance advantage, clouding coaches and practitioners' perceptions regarding current ability and future potential. This may result in the exclusion of talented, yet less physically gifted athletes. Participants were 91 male (n = 47) and female (n = 44) elite British Junior tennis players, 8-17 years of age (12.5 ± 1.9 years). Height and body mass were measured and compared to growth charts; hand-wrist radiographs were taken. Skeletal age (SA) was estimated with the Fels method and contrasted to chronological age (CA). Mean height and body mass of individual players ranged between the 50th and 90th centiles for age and sex. Females were advanced in SA relative to CA (0.3-0.89 years.) from 8 years. Males were average to delayed in maturation from 8 to 12 years, but advanced in SA from 14 to 16 years (0.75-1.23 years). Individual differences in growth and maturation appear to contribute towards the selection of elite junior tennis players, with a bias towards males and females who are advanced in maturation and comparatively tall and heavy for their age. This has important implications for talent identification and development.

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

    PubMed Central

    2009-01-01

    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 <14 years as well as having a sexual debut and unprotected sex <16 years. Males with earlier pubertal onset were more likely to report fighting and aggressive responses to emotional upset during early adolescence while females were more likely to report being bullied and having taken more time off school. 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. PMID:19958543

  16. Thermal Maturation of Gas Shale Systems

    NASA Astrophysics Data System (ADS)

    Bernard, Sylvain; Horsfield, Brian

    2014-05-01

    Shale gas systems serve as sources, reservoirs, and seals for unconventional natural gas accumulations. These reservoirs bring numerous challenges to geologists and petroleum engineers in reservoir characterization, most notably because of their heterogeneous character due to depositional and diagenetic processes but also because of their constituent rocks' fine-grained nature and small pore size -- much smaller than in conventional sandstone and carbonate reservoirs. Significant advances have recently been achieved in unraveling the gaseous hydrocarbon generation and retention processes that occur within these complex systems. In addition, cutting-edge characterization technologies have allowed precise documentation of the spatial variability in chemistry and structure of thermally mature organic-rich shales at the submicrometer scale, revealing the presence of geochemical heterogeneities within overmature gas shale samples and, notably, the presence of nanoporous pyrobitumen. Such research advances will undoubtedly lead to improved performance, producibility, and modeling of such strategic resources at the reservoir scale.

  17. Biological Maturation in Adolescence and the Development of Drinking Habits and Alcohol Abuse among Young Males: A Prospective Longitudinal Study.

    ERIC Educational Resources Information Center

    Andersson, Tommy; Magnusson, David

    1990-01-01

    The relationship between biological maturation, as evidenced by skeletal growth, during adolescence and the development of drinking habits and alcohol abuse was studied for a representative group of Swedish males (N=88). Early and late maturers had more advanced drinking habits at age 14 years than did normally maturing subjects. (TJH)

  18. Testicular and epididymal sperm reserves and sperm production of pubertal boars fed dietary fumonisin B(1).

    PubMed

    Gbore, F A; Egbunike, G N

    2008-05-01

    Twenty-four male Large White weaning pigs of 8-9 weeks of age averaging 6.94+/-0.26 kg were used to evaluate the effect of dietary fumonisin B(1) (FB(1)) on sperm reserves and production of pubertal boars. The animals were randomly assigned to 4 diets containing 0.2, 5.0, 10.0 and 15.0 mg FB(1)/kg constituting the control, diets 1, 2 and 3, respectively, in a 6-month feeding trial. Dietary FB(1) above 5mg/kg significantly (P<0.05) reduced testicular and epididymal sperm reserves as well as the daily sperm production (DSP) per boar. The total caudal sperm reserves of the animals on diets 2 and 3 were about 70% of those on the control diet. The DSP of the animals on the control diet and diet 1 were significantly (P<0.05) higher than those on diets 2 and 3. The study revealed that male weaning pigs for breeding should not be exposed to dietary FB(1) higher than 5mg/kg for no suppression in sperm production and reproductive performance.

  19. Disruption of pubertal onset by exogenous testosterone and estrogen in two species of rodents.

    PubMed

    Pak, Toni R; Lynch, G Robert; Ziegler, D Matthew; Lunden, Jason B; Tsai, Pei-San

    2003-01-01

    The administration of adult physiological levels of testosterone (T) and 17beta-estradiol (E(2)) to male Siberian hamsters was previously shown to delay the onset of puberty. To examine whether this is a response common to other rodents, we investigated whether exogenous steroids also alter the onset of puberty in Syrian hamsters and mice. Juvenile male Syrian hamsters and mice were implanted with Silastic capsules containing T, E(2), or cholesterol control. After 15 days, plasma, pituitaries, and testes were processed for histological analysis or measurements of gonadotropins and circulating steroid hormones. T and E(2) implants reduced testis mass and gonadotropin stores in both species and arrested spermatogenesis in Syrian hamsters. In contrast, spermatogenesis in mice was unaffected by T and only modestly affected by E(2). Although E(2) inhibited circulating follicle-stimulating hormone (FSH) in both species, T inhibited circulating FSH in mice only. Overall, our results demonstrate that the hypothalamic-pituitary-gonadal axis of each rodent species responds uniquely to T and E(2) during the pubertal transition. Despite the highly varied effects of T and E(2) in these two species, the ability of steroid hormones to disrupt the onset of puberty appears to be a feature common to many rodents.

  20. Lifelong exposure to n-3 PUFA affects pubertal mammary gland development.

    PubMed

    Anderson, Breanne M; MacLennan, Mira B; Hillyer, Lyn M; Ma, David W L

    2014-06-01

    There is growing evidence that early developmental periods may importantly influence future breast cancer risk. Also, there is great interest in the role of dietary fat in breast cancer risk, but the role of dietary fat during pubertal mammary gland development remains poorly understood. This study investigated the effect of n-3 polyunsaturated fatty acids (PUFA) using complementary dietary and genetic approaches to examine the effect of lifelong exposure of n-3 PUFA or n-6 PUFA (control) on mammary gland development and fatty acid composition. n-3 PUFA from both diet and genetics were enriched in mammary glands as early as 3 weeks of age. Parameters related to mammary gland development, including number of terminal end buds (TEB), percent coverage of ductal tree, and infiltration of TEB, were influenced by n-3 PUFA at 3 and 4 weeks of age. Overall, findings suggest that n-3 PUFA incorporation into the mammary gland early in life plays a role in the morphological development of the mammary gland during puberty.

  1. Biomarkers for assessing reproductive development and health: Part 1--Pubertal development.

    PubMed Central

    Rockett, John C; Lynch, Courtney D; Buck, Germaine M

    2004-01-01

    The proposed National Children's Study has helped raise awareness of the issues related to children's health and the importance of monitoring the growth and development of children from preconception through adulthood. Many genetic predispositions can adversely impact the normal development process, and various environmental exposures have been linked to adverse reproductive health in rodent models and a small number of accidental human exposures. To monitor reproductive health and identify adverse effects at the earliest possible juncture, investigators must develop a network of biomarkers covering all stages and aspects of reproductive development and function. Biomarkers are biological indicators that can be measured repeatedly and are informative on one or more aspects of biological development or function. They can range from the anatomical level down to the molecular level and may provide information on the nature of an exposure, the effect of an exposure, or the susceptibility of individuals or populations to the toxic effects of an exposure. In theory, biomarkers can be used to monitor a wide variety of conditions and responses ranging from abnormal development to early indicators of late-onset disease. The main stumbling block with this theory has been finding appropriate biomarkers for particular conditions and exposures. Such biomarkers must be easily accessible, robust, and sensitive. Ideally, they will be expressed across a large section of the population, and can be monitored quickly, easily, conveniently, and with minimal cost. In this review, we discuss some of the current and emerging biomarkers of human pubertal development. PMID:14698938

  2. PRB mines mature

    SciTech Connect

    Buchsbaum, L.

    2007-08-15

    Already seeing the results of reclamation efforts, America's largest surface mines advance as engineers prepare for the future. 30 years after the signing of the Surface Mining Control and Reclamation Act by Jimmy Carter, western strip mines in the USA, especially in the Powder River Basin, are producing more coal than ever. The article describes the construction and installation of a $38.5 million near-pit crusher and overland belt conveyor system at Foundation Coal West's (FCW) Belle Ayr surface mine in Wyoming, one of the earliest PRB mines. It goes on to describe the development by Rio Tinto of an elk conservatory, the Rochelle Hill Conservation Easement, on reclaimed land at Jacobs Ranch, adjacent to the Rochelle Hills. 4 photos.

  3. Career Maturity of Students in Accelerated versus Traditional Programs

    ERIC Educational Resources Information Center

    Borges, Nicole J.; Richard, George V.; Duffy, Ryan D.

    2007-01-01

    The authors assessed the career maturity of students in accelerated versus traditional academic programs. Students in traditional programs were hypothesized to be more advanced regarding their career decision making and development when compared with students in accelerated programs. The Medical Career Development Inventory (see M. L. Savickas,…

  4. Testicular expression of the Lin28/let-7 system: Hormonal regulation and changes during postnatal maturation and after manipulations of puberty

    PubMed Central

    Sangiao-Alvarellos, S.; Manfredi-Lozano, M.; Ruiz-Pino, F.; León, S.; Morales, C.; Cordido, F.; Gaytán, F.; Pinilla, L.; Tena-Sempere, M.

    2015-01-01

    The Lin28/let-7 system, which includes the RNA-binding proteins, Lin28a/Lin28b, and let-7 miRNAs, has emerged as putative regulator of puberty and male gametogenesis; yet, its expression pattern and regulation in postnatal testis remain ill defined. We report herein expression profiles of Lin28 and let-7 members, and related mir-145 and mir-132, in rat testis during postnatal maturation and in models of altered puberty and hormonal deregulation. Neonatal expression of Lin28a and Lin28b was low and rose markedly during the infantile period; yet, expression patterns diverged thereafter, with persistently elevated levels only for Lin28b, which peaked at puberty. Let-7a, let-7b, mir-132 and mir-145 showed profiles opposite to Lin28b. In fact, let-7b and mir-145 were abundant in pachytene spermatocytes, but absent in elongating spermatids, where high expression of Lin28b was previously reported. Perturbation of puberty by neonatal estrogenization reverted the Lin28/let-7 expression ratio; expression changes were also detected in other models of delayed puberty, due to early photoperiod or nutritional manipulations. In addition, hypophysectomy or growth hormone (GH) deficiency revealed regulation of this system by gonadotropins and GH. Our data document the expression profiles of the Lin28/let-7 system in rat testis along postnatal/pubertal maturation, and their perturbation in models of pubertal and hormonal manipulation. PMID:26494358

  5. Skeletal maturation in individuals with Down's syndrome: Comparison between PGS curve, cervical vertebrae and bones of the hand and wrist

    PubMed Central

    Carinhena, Glauber; Siqueira, Danilo Furquim; Sannomiya, Eduardo Kazuo

    2014-01-01

    Introduction This study was conducted with the aim of adapting the methods developed by Martins and Sakima to assess skeletal maturation by cervical vertebrae in the pubertal growth spurt (PGS) curve. It also aimed to test the reliability and agreement between those methods and the method of hand and wrist radiograph when compared two by two and all together. Methods The sample comprised 72 radiographs, with 36 lateral radiographs of the head and 36 hand-wrist radiographs of 36 subjects with Down's syndrome (DS), 13 female and 23 male, aged between 8 years and 6 months and 18 years and 7 months, with an average age of 13 years and 10 months. Results and Conclusions Results revealed that adapting the methods developed by Martins and Sakima to assess skeletal maturation by cervical vertebrae in the curve of PGS is practical and useful in determining the stage of growth and development of individuals. The stages of maturation evaluated by cervical vertebrae and ossification centers observed in radiographs of the hand and wrist were considered reliable, with excellent level of agreement between the methods by Hassel and Farman as well as Baccetti, Franchi and McNamara Jr and Martins and Sakima. Additionally, results revealed an agreement that ranged between reasonable to good for the three methods used to assess the skeletal maturation, showing statistical significance. PMID:25279522

  6. Identical Allelic Losses in Mature Teratoma and Other Histologic Components of Malignant Mixed Germ Cell Tumors of the Testis

    PubMed Central

    Kernek, Kevin M.; Ulbright, Thomas M.; Zhang, Shaobo; Billings, Steven D.; Cummings, Oscar W.; Henley, John D.; Michael, Helen; Brunelli, Matteo; Martignoni, Guido; Foster, Richard S.; Eble, John N.; Cheng, Liang

    2003-01-01

    Teratomas of the testis in post-pubertal patients are histologically diverse tumors that often coexist with other types of germ cell tumors. Using laser capture microdissection and loss of heterozygosity analysis, we investigated the clonality of mature teratoma and its relationship to other components of malignant mixed germ cell tumors to gain potential insight into the histogenetic relationship of teratoma with other germ cell tumor components. All 16 patients had mature teratoma as one component of their mixed germ cell tumors. The other histological subtypes included immature teratoma, seminoma, embryonal carcinoma, yolk sac tumor, and choriocarcinoma. Laser-assisted microdissection was performed on the formalin-fixed, paraffin-embedded tissue. Polymerase chain reaction was used to amplify genomic DNA at specific loci on chromosome 1p36.2 (D1S508), 2q22–32 (D2S156), 9p21–22 (D9S162), 11p13 (D11S903), 12q22–23 (D12S1051), and 18q21 (D18S46). Fourteen of 16 (88%) cases showed allelic loss in one or more components of the mixed germ cell tumors. Fourteen of 16 mature teratomas showed allelic loss in at least one of six microsatellite polymorphic markers analyzed. The frequency of allelic loss in mature teratoma was 50% (7 of 14) with D1S508, 33% (5 of 15) with D2S156, 58% (7 of 12) with D9S162, 43% (6 of 14) with D11S903, 20% (3 of 15) with D12S1051, and 33% (5 of 15) with D18S46. Completely concordant allelic loss patterns between mature teratoma and all of the other germ cell tumor components were seen in 10 of 14 tumors in which mature teratoma showed loss of heterozygosity. Our data support the common clonal origin of mature teratoma with other components of malignant mixed germ cell tumors of the testis. PMID:14633619

  7. A pubertal immune challenge alters the antidepressant-like effects of chronic estradiol treatment in inbred and outbred adult female mice

    PubMed Central

    Ismail, Nafissa; Kumlin, Ashley M.; Blaustein, Jeffrey D.

    2012-01-01

    Puberty is a period characterized by brain reorganization that contributes to the development of neural and behavioral responses to gonadal steroids. A single injection of the bacterial endotoxin, lipopolysaccharide (LPS), during the pubertal period decreases sexual receptivity in response to ovarian hormones in adulthood. Because chronic estradiol treatment alleviates depression-like symptoms in ovariectomized adult mice, we investigated the effect of pubertal LPS treatment on estradiol’s antidepressant effects. We hypothesized that pubertal LPS treatment would decrease the antidepressant-like effect of estradiol in adult ovariectomized female mice, as it decreases other behavioral responses to ovarian hormones. As expected, chronic estradiol treatment decreased depression-like behavior, as measured by the duration of immobility, in saline-treated mice from two different strains, as well as in mice treated with LPS in adulthood. In contrast, in mice treated pubertally with LPS, estradiol strikingly increased the duration of immobility. No difference in body weight and in locomotion was found among the groups, suggesting that the differences in depression-like behavior were not due to differences in body weight or locomotor activity between LPS-treated and control mice. These results suggest that exposure to an immune challenge during the pubertal period alters the responsiveness of depression-like behavior to estradiol. PMID:23036617

  8. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  9. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  10. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will...

  11. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will...

  12. 7 CFR 51.3746 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3746 Mature. Mature means that the melon has reached the stage of maturity which will insure the proper completion of the...

  13. Simplified isolation and enrichment of spermatogonial stem-like cells from pubertal domestic cats (Felis catus).

    PubMed

    Tiptanavattana, Narong; Techakumphu, Mongkol; Tharasanit, Theerawat

    2015-11-01

    The efficiency of spermatogonial stem cell (SSC) isolation and culture from pubertal donors is currently poor primarily, because of contamination with other testicular cells. This study aimed to purify SSC-like cells using different extracellular matrixes and a discontinuous gradient density. In experiment 1, testes (n=6) were analyzed for histology and SSC-related protein expressions (laminin, SSEA-4, DDX-4 and GFRα-1). After enzymatic digestion, the cell suspension was plated onto either a laminin- or gelatin-coated dish. The number of SSC-like cells was determined at 15, 30 and 60 min of culture (experiment 2). Experiment 3 was performed to test whether or not the additional step of Percoll gradient density centrifugation could really improve purification of SSC-like cells. Testicular histology revealed complete spermatogenesis with laminin expression essentially at the basal lamina of the seminiferous tubules. SSEA-4 and GFRα-1 co-localized with DDX-4 in the spermatogonia. The relative percentage of SSC-like cells, as determined by cells expressing SSEA-4 (59.42 ± 2.18%) and GFRα-1 (42.70 ± 1.28%), revealed that the highest SSC-like cell purity was obtained with the 15-min laminin-coated dish compared with other incubation times and gelatin treatment (P<0.05). Percoll treatment prior to laminin selection (15 min) significantly improved SSC-like cell recovery (91.33 ± 0.14%, P<0.001) and purity (83.82 ± 2.05% for SSEA-4 and 64.39 ± 1.51% for GFRα-1, P<0.05). These attached cells demonstrated a typical SSC-like cell morphology and also expressed POU5F1, RET and ZBTB16 mRNA. In conclusion, double enrichment with Percoll gradient density centrifugation and laminin plating highly enriched the SSC-like cells population.

  14. Indicators of oxidative stress in weanling and pubertal rats following exposure to nicotine via milk.

    PubMed

    Halima, Ben Ahmed; Sarra, Khlifi; Kais, Rtibi; Salwa, Elfazaa; Najoua, Gharbi

    2010-06-01

    Nicotine, a major toxic component of tobacco, has been identified as an important risk factor for infant and children diseases. It is concentrated in breast milk and is absorbed by the infant. The purpose of the present study was to investigate the effects of maternal nicotine exposure during lactation on breast-fed rats and at the pubertal age by measuring biomarkers of oxidative stress. Particularly, a new parameter, the thiol concentration was evaluated. Two groups of lactating Wistar rats were used. For the first group, female rats were given an intraperitoenal injection of nicotine or saline (2 mg/kg per day) during lactation. For the second group, we reproduced the same process described above and then the female and male pups were separately kept after weaning without any treatment until the puberty (at 45 days of age). In the liver and lung of the offspring, we examined the malondialdehyde (MDA) level, the thiol concentration, and the activities of two antioxidant enzymes: superoxyde dismutase (SOD) and catalase (CAT). In the plasma, alanine amino transferase (ALT) and aspartate amino transferase (AST) activities were measured. For rats aged 21 days, the treatment significantly reduced the thiol concentration, SOD, and CAT activities but increased MDA level, AST, and ALT activities. For rats aged 45 days, the males and females did not react the same way. In fact, the males were more affected. These results indicate that maternal nicotine exposure during the lactation period induces oxidative stress in the liver and lung of lactating offspring, which is maintained until the puberty, especially for the male rats. PMID:19900975

  15. High prevalence of abnormal adrenal response in girls with central precocious puberty at early pubertal stages.

    PubMed

    Lazar, L; Kauli, R; Bruchis, C; Nordenberg, J; Galatzer, A; Pertzelan, A

    1995-10-01

    Abnormal adrenal response is often observed in girls with precocious adrenarche (1). We studied the adrenal response in 112 girls with idiopathic true central precocious puberty (CPP) at early stages of puberty compared to that in 21 girls with normal puberty (controls). The aims of this study were to determine the prevalence of abnormal adrenal response at early stages of puberty, the possible correlation of abnormal adrenal response with pubertal signs at onset of puberty and with plasma androgen levels, and a possible association with the activity of the hypothalamic-pituitary-gonadal (HPG) axis. All participants underwent a combined i.v. adrenocorticotropic hormone (ACTH)-gonadotropin-releasing hormone (GnRH) test at Tanner stage 2-3: 62 of the CPP girls before and 50 during treatment with GnRH analog. The stimulated levels of 17-hydroxypregnenolone (17OHPreg) and the stimulated 17OHPreg/17-hydroxyprogesterone ratio were analyzed and compared to previously reported norms. The result revealed three patterns of adrenal response: normal (17OHPreg < or = 24 nmol/l and 17OHPreg/17OHP ratio < or = 7) in 50/112 (44.6%) CPP patients and 17/21 (80.9%) controls; exaggerated (17OHPreg > 24 nmol/l, 17OHPreg/17OHP ratio < or = 7) in 50/112 (44.6%) CPP patients and 3/21 (14.3%) controls; and non-classical 3 beta-hydroxysteroid dehydrogenase deficiency (17OHPreg > 24 nmol/l and 17OHPreg/17OHP ratio > 7) in 12/112 (10.8%) CPP patients and 1/21 (4.8%) controls. The clinical features at onset of puberty were comparable in all girls with the CPP in spite of the different adrenal response patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed

    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.

  17. Sex-dependent consequences of pre-pubertal gonadectomy: Social behavior, stress and ethanol responsivity.

    PubMed

    Kim, Esther U; Spear, Linda P

    2016-01-01

    Alcohol consumption can be enhanced or moderated by sensitivity to its aversive and appetitive properties, including positive social outcomes. These differences emerge post-pubertally, suggesting a potential role of gonadal hormones. To determine the role of gonadal hormones in sensitivity to the social impairing and social context-related attenuations in the aversive effects of ethanol, prepubertal male and female rats were gonadectomized (GX) or sham (SH) operated on postnatal day (P) 25, or left non-manipulated (NM). In adulthood (P70), rats were restrained for 90 min prior to challenge with 0.0 or 1.0 g/kg ethanol and social interaction (SI) testing. At P77, groups of 4 same-sex littermates from the same surgical condition were given access to a supersaccharin (SS) solution (3% sucrose, 0.125% saccharin), followed by an intraperitoneal injection of ethanol (0.0, 0.50, 1.0, 1.5 g/kg). Intakes of SS were examined 24h later for expression of conditioned taste aversions. Acute stress prior to SI testing increased frequency of play fighting in both sexes, whereas there were no GX effects on this measure, social investigation nor contact. GX, however, decreased baseline social preference (a social anxiety-like effect) in males, while inducing anxiolytic-like increases in baseline social preference in females. The social drinking test revealed that females developed ethanol conditioned taste aversions at a lower dose relative to males, regardless of surgical condition. These findings suggest a potential role for gonadal hormones in moderating social-anxiety like behaviors but not sensitivity to the social impairing effects of ethanol or ethanol's aversive consequences in a social context.

  18. Sexually dimorphic innate immunological responses of pre-pubertal Brahman cattle following an intravenous lipopolysaccharide challenge.

    PubMed

    Carroll, Jeffery A; Burdick Sanchez, Nicole C; Hulbert, Lindsey E; Ballou, Michael A; Dailey, Jeffery W; Caldwell, Lisa C; Vann, Rhonda C; Welsh, Thomas H; Randel, Ronald D

    2015-08-15

    This study was designed to characterize potential sexually dimorphic immunological responses following a lipopolysaccharide (LPS) challenge in beef cattle. Six female (heifers) and five male (bulls) Brahman calves (average age=253 ± 19.9 and 288 ± 47.9 days; average body weight=194 ± 11 kg and 247 ± 19 kg for heifers and bulls, respectively) were challenged with LPS (0.25 μg LPS/kg body weight). Following administration of LPS, all cattle displayed increased sickness behavior beginning at 0.5h, with heifers on average displaying less sickness behavior than bulls. A febrile response was observed in all animals following LPS administration, with a maximum response observed from 4 to 5.5h. The average rectal temperature response was greater in heifers than bulls. In all cattle there were elevated serum concentrations of cortisol from 0.5 to 8h, TNF-α from 1 to 2.5h, IL-6 from 2 to 8h, and IFN-γ from 2.5 to 7h after LPS challenge. Additionally, serum concentrations of TNF-α were greater in heifers than bulls from 1.5 to 2h after the LPS challenge. Concentrations of IFN-γ were also greater on average in bulls than heifers. Leukopenia occurred from 1 to 8h, with a decreased neutrophil to lymphocyte ratio for the first 5h among all calves. These data demonstrate the existence of a sexually dimorphic acute-phase response in pre-pubertal Brahman calves. Specifically, heifers may have a more robust acute response to LPS challenge, even though bulls display more signs of sickness. PMID:26144890

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

    PubMed

    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.

  20. Pubertal exposure to di-(2-ethylhexyl) phthalate influences social behavior and dopamine receptor D2 of adult female mice.

    PubMed

    Wang, Ran; Xu, Xiaohong; Zhu, Qingjie

    2016-02-01

    DEHP, one of the most commonly phthalates used in plastics and many other products, is an environmental endocrine disruptor (EED). Puberty is another critical period for the brain development besides the neonatal period and is sensitive to EEDs. Social behavior is organized during puberty, so the present study is to investigate whether pubertal exposure to DEHP influenced social behavior of adult female mice. The results showed that pubertal exposure to DEHP for 2 weeks did not change the serum level of 17β-estradiol and the weight of uterus of adult females, but decreased the number of grid crossings and the frequency of rearing, and increased grooming in open field. DEHP reduced the open arm entries and the time spent in open arms in the elevated plus maze. DEHP reduced mutual sniffing and grooming between unfamiliar conspecifics in social play task and reduced the right chamber (containing unfamiliar female mouse) entries and the frequency of sniffing unfamiliar female mouse. DEHP at 1 mg kg(-1) d(-1) reduced the time spent in right chamber. Furthermore, Western blot analyses showed that DEHP decreased the levels of estrogen receptor β (ERβ), dopamine receptor D2, and the phosphorylation of ERKs in striatum. These results suggest that pubertal exposure to DEHP impaired social investigation and sociability and influenced anxiety-like state of adult female mice. The decreased activity of ERK1/2, and the down-regulated D2 and ERβ in striatum may be associated with the DEHP-induced changes of emotional and social behavior in mice. PMID:26524146

  1. Pubertal exposure to di-(2-ethylhexyl) phthalate influences social behavior and dopamine receptor D2 of adult female mice.

    PubMed

    Wang, Ran; Xu, Xiaohong; Zhu, Qingjie

    2016-02-01

    DEHP, one of the most commonly phthalates used in plastics and many other products, is an environmental endocrine disruptor (EED). Puberty is another critical period for the brain development besides the neonatal period and is sensitive to EEDs. Social behavior is organized during puberty, so the present study is to investigate whether pubertal exposure to DEHP influenced social behavior of adult female mice. The results showed that pubertal exposure to DEHP for 2 weeks did not change the serum level of 17β-estradiol and the weight of uterus of adult females, but decreased the number of grid crossings and the frequency of rearing, and increased grooming in open field. DEHP reduced the open arm entries and the time spent in open arms in the elevated plus maze. DEHP reduced mutual sniffing and grooming between unfamiliar conspecifics in social play task and reduced the right chamber (containing unfamiliar female mouse) entries and the frequency of sniffing unfamiliar female mouse. DEHP at 1 mg kg(-1) d(-1) reduced the time spent in right chamber. Furthermore, Western blot analyses showed that DEHP decreased the levels of estrogen receptor β (ERβ), dopamine receptor D2, and the phosphorylation of ERKs in striatum. These results suggest that pubertal exposure to DEHP impaired social investigation and sociability and influenced anxiety-like state of adult female mice. The decreased activity of ERK1/2, and the down-regulated D2 and ERβ in striatum may be associated with the DEHP-induced changes of emotional and social behavior in mice.

  2. Relationship between the relative age effect and anthropometry, maturity and performance in young soccer players.

    PubMed

    Gil, Susana Maria; Badiola, Aduna; Bidaurrazaga-Letona, Iraia; Zabala-Lili, Jon; Gravina, Leyre; Santos-Concejero, Jordan; Lekue, Jose Antonio; Granados, Cristina

    2014-01-01

    The presence of the relative age effect (RAE) has been widely reported; however, its underlying causes have not yet been determined. With this in mind, the present study examined if anthropometry and performance were different amongst older and younger soccer players born in the same year. Eighty-eight young soccer players participated in the study (age 9.75 ± 0.30). Anthropometric measurements, physical tests (sprint, agility, endurance test, jump and hand dynamometry) and the estimation of the maturity status were carried out. Most players (65.9%) were born in the first half of the year. Older players were taller (P < 0.05), had longer legs (P < 0.01) and a larger fat-free mass (P < 0.05). Maturity offset was smaller in the older boys (P < 0.05); however, age at peak height velocity was similar. Older boys performed better in velocity and agility (P < 0.05) and particularly in the overall score of performance (P < 0.01). Stepwise regression analysis revealed that chronological age was the most important variable in the agility test and the overall score, after the skinfolds (negative effect). We report differences in anthropometry and physical performance amongst older and younger pre-pubertal soccer players. These differences may underlie the RAE.

  3. Swimming physiology of European silver eels (Anguilla anguilla L.): energetic costs and effects on sexual maturation and reproduction.

    PubMed

    Palstra, Arjan P; van den Thillart, Guido E E J M

    2010-09-01

    The European eel migrates 5,000-6,000 km to the Sargasso Sea to reproduce. Because they venture into the ocean in a pre-pubertal state and reproduce after swimming for months, a strong interaction between swimming and sexual maturation is expected. Many swimming trials have been performed in 22 swim tunnels to elucidate their performance and the impact on maturation. European eels are able to swim long distances at a cost of 10-12 mg fat/km which is 4-6 times more efficient than salmonids. The total energy costs of reproduction correspond to 67% of the fat stores. During long distance swimming, the body composition stays the same showing that energy consumption calculations cannot be based on fat alone but need to be compensated for protein oxidation. The optimal swimming speed is 0.61-0.67 m s(-1), which is approximately 60% higher than the generally assumed cruise speed of 0.4 m s(-1) and implies that female eels may reach the Sargasso Sea within 3.5 months instead of the assumed 6 months. Swimming trials showed lipid deposition and oocyte growth, which are the first steps of sexual maturation. To investigate effects of oceanic migration on maturation, we simulated group-wise migration in a large swim-gutter with seawater. These trials showed suppressed gonadotropin expression and vitellogenesis in females, while in contrast continued sexual maturation was observed in silver males. The induction of lipid deposition in the oocytes and the inhibition of vitellogenesis by swimming in females suggest a natural sequence of events quite different from artificial maturation protocols. PMID:20390348

  4. [Masculinization of prepubertal and pubertal females of Sphaeroma serratum Fabr., (Crustacea Isopoda Flabellifera) by implantation of an androgenic gland of pubertal male].

    PubMed

    Raimond, R; Juchault, P

    1983-04-01

    In Sphaeroma serratum, the differentiation of the male external sexual characteristics, as a result of an androgenic gland implant, proceeds more easily in females in vitellogenesis than in immature females. On the contrary, the transformation of the gonads is quicker and more obvious in immature females than in mature ones. This transformation which leads, in all cases, to an inversion of the ovary to a functional testicle able to produce spermatozoa, always occurs without any differentiation of an androgenic gland, contrary to what can be observed with Oniscoïds. The details of the external sexual differentiation of the grafted females can be related to the functioning of a protocerebral neurosecretory center having, as in males, an androinhibitory effect on the androgenic gland implant; the activity of this center, which seems to correspond to the center secreting VIH, would be particularly high with immature females and would become very low--or nonexistent--in females in vitellogenesis.

  5. Pubertal Development and Behavior: Hormonal Activation of Social and Motivational Tendencies

    ERIC Educational Resources Information Center

    Forbes, Erika E.; Dahl, Ronald E.

    2010-01-01

    Adolescence is a time of dramatic changes including rapid physical growth, the onset of sexual maturation, the activation of new drives and motivations, and a wide array of social and affective changes and challenges. This review focuses on behavioral changes in this interval and is organized by the claim that a key set of these adolescent changes…

  6. Growth Patterns in Pubertal HIV-infected Adolescents and their Correlation with Cytokines, IGF-1, IGFBP-1 and IGFBP-3

    PubMed Central

    Kessler, Marion; Kaul, Aditya; Santos-Malavé, Claritsa; Borkowsky, William; Kessler, Jason; Shah, Bina

    2014-01-01

    Objective To describe the final adult height (FAH) and pubertal growth patterns in HIV-infected adolescents and to compare this to an age matched population of seroreverting HIV-exposed uninfected (HEU) adolescents. Further, to evaluate the interplay of proinflammatory cytokines (PIC) with IGF-1, IGFBP-3 and IGFBP-1 during the pubertal growth spurt. Methods HIV-infected adolescents (n=34) and 12 HEU patients, who had achieved FAH were evaluated. Auxologic data, viral load, CD4 count and HAART were obtained via a retrospective chart review. Serum IL-1 α, IL-6, TNF-α, IGFBP-1, IGFBP-3 and IGF-1 were assessed. Results The mean FAH for the HIV-infected group was SDS -0.78 (+/−1.1) compared to 0.05 (+/−0.78) for the HEU (p = 0.034). There was a positive correlation between CD4 count and FAH (p=0.019). The mean age and magnitude of peak growth velocity (GV) was within normal limits. IL-1 α, IL-6, TNF α, IGFBP-3 and IGF-1 were not significantly correlated with HIV RNA or height. IGFBP-1 was detectable in 100% of poorly controlled HIV-infected patients and 25% of the HEU cohort (p = 0.0003). Conclusions The FAH of HIV-infected patients was significantly shorter than HEU and positively correlated with CD4 T-lymphocyte count. Our cohort demonstrated normal timing and magnitude of peak GV during puberty. PMID:23612635

  7. Motivational Maturity and Helping Behavior

    ERIC Educational Resources Information Center

    Haymes, Michael; Green, Logan

    1977-01-01

    Maturity in conative development (type of motivation included in Maslow's needs hierarchy) was found to be predictive of helping behavior in middle class white male college students. The effects of safety and esteem needs were compared, and the acceptance of responsibility was also investigated. (GDC)

  8. Steps to Maturity Program. Evaluation.

    ERIC Educational Resources Information Center

    Nanaimo School District #68 (British Columbia).

    In fall 1989, the Nanaimo (British Columbia) School District No. 68 asked five people, selected from the school system and community, to evaluate the "Steps to Maturity" Program (STMP), a district-wide family life education and affective development program that has developed gradually since 1972. The evaluation team interviewed a large number of…

  9. Enticing Mature Females into College.

    ERIC Educational Resources Information Center

    Loseth, Lexie; Moreau, Linda

    Following a review of the literature on mature female students, this paper examines enrollment trends in a selection of colleges in Alberta (Canada) and presents the findings of a survey of returning women students at Red Deer College. The literature review highlights factors related to the personal and professional development of women graduates…

  10. Adolescent Maturation in Transitioning Cultures.

    ERIC Educational Resources Information Center

    Mulroy, Kevin; Palacios, Anna; Reid, Robert E.

    This is a theoretical study of adolescent maturation within a cultural context. Personality development and disintegration due to the pressure of a dominant culture on a minority culture is considered. An attempt is made to understand how teachers might assist students to work out their psychological growth by story telling. The need for cultural…

  11. College Freshmen: Turmoil or Maturity?

    ERIC Educational Resources Information Center

    Rubin, Stephen

    1988-01-01

    Administered the Personal Orientation Inventory, Tennessee Self-Concept Scale, a group Rorschach, and a biographical questionnaire to 24 randomly selected freshmen from a small Northwest liberal arts college. Results indicated that the young adults responded differently from either children or mature adults. Findings support contention that…

  12. The People Capability Maturity Model

    ERIC Educational Resources Information Center

    Wademan, Mark R.; Spuches, Charles M.; Doughty, Philip L.

    2007-01-01

    The People Capability Maturity Model[R] (People CMM[R]) advocates a staged approach to organizational change. Developed by the Carnegie Mellon University Software Engineering Institute, this model seeks to bring discipline to the people side of management by promoting a structured, repeatable, and predictable approach for improving an…

  13. Rhetorical Maturity: Definition and Development.

    ERIC Educational Resources Information Center

    Miller, Susan

    Lawrence Kohlberg's stages of moral development, when applied to theories of teaching composition, support any method or material that refers to the age and prior experience of the writer and the newness of the task the writer is attempting. Rhetorical development and maturation in the ability to write and argue persuasively are partly conceptual…

  14. A randomized school-based jumping intervention confers site and maturity-specific benefits on bone structural properties in girls: a hip structural analysis study.

    PubMed

    Petit, M A; McKay, H A; MacKelvie, K J; Heinonen, A; Khan, K M; Beck, T J

    2002-03-01

    We compared 7-month changes in bone structural properties in pre- and early-pubertal girls randomized to exercise intervention (10-minute, 3 times per week, jumping program) or control groups. Girls were classified as prepubertal (PRE; Tanner breast stage 1; n = 43 for intervention [I] and n = 25 for control [C]) or early-pubertal (EARLY; Tanner stages 2 and 3; n = 43 for I and n = 63 for C). Mean +/- SD age was 10.0 +/- 0.6 and 10.5 +/- 0.6 for the PRE and EARLY groups, respectively. Proximal femur scans were analyzed using a hip structural analysis (HSA) program to assess bone mineral density (BMD), subperiosteal width, and cross-sectional area and to estimate cortical thickness, endosteal diameter, and section modulus at the femoral neck (FN), intertrochanter (IT), and femoral shaft (FS) regions. There were no differences between intervention and control groups for baseline height, weight, calcium intake, or physical activity or for change over 7 months (p > 0.05). We used analysis of covariance (ANCOVA) to examine group differences in changes of bone structure, adjusting for baseline weight, height change, Tanner breast stage, and physical activity. There were no differences in change for bone structure in the PRE girls. The more mature girls (EARLY) in the intervention group showed significantly greater gains in FN (+2.6%, p = 0.03) and IT (+1.7%, p = 0.02) BMD. Underpinning these changes were increased bone cross-sectional area and reduced endosteal expansion. Changes in subperiosteal dimensions did not differ. Structural changes improved section modulus (bending strength) at the FN (+4.0%, p = 0.04), but not at the IT region. There were no differences at the primarily cortical FS. These data provide insight into geometric changes that underpin exercise-associated gain in bone strength in early-pubertal girls. PMID:11874228

  15. 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

    EPA Science Inventory

    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...

  16. THE EFFECTS OF ATRAZINE METABOLITES ON PUBERTY AND THYROID FUNCTION IN THE MALE WISTAR RATS: AN EVALUATION IN THE MALE PUBERTAL PROTOCOL

    EPA Science Inventory

    The Effects of Atrazine Metabolites on Puberty in the Male Wistar Rat. D L Guidici, R L Cooper and T E Stoker. Endocrinology Branch, NHEERL, U.S. Environmental Protection Agency, RTP, NC.
    Sponsor: R J Kavlock.
    Atrazine (ATR), a chlorotriazine herbicide, alters pubertal pr...

  17. EVALUATION OF AMMONIUM PERCHLORATE IN THE ENDOCRINE DISRUPTOR SCREENING AND TESTING PROGRAM'S MALE PUBERTAL PROTOCOL: ABILITY TO DETECT EFFECTS OF THYROID ENDPOINTS.

    EPA Science Inventory

    The U.S EPA Endocrine Disruptor Screening Program Tier 1 male pubertal protocol was designed to detect reproductive development and thyroid function. One purpose of this in vivo protocol is to detect thyrotoxicants via a number of different mechanisms of action. Here we evaluate ...

  18. Modifications to the Current EPA Endocrine Disruptor Screening Program's Tier 1 Female Pubertal Protocol: A Study on the Effects of the Chlorotriazine Simazine

    EPA Science Inventory

    Currently the US EPA is implementing a screening program for environmental endocrine disruptors. One of the in vivo assays in the Tier 1 Screen of the Endocrine Disruptors Screening Program (EDSP) is a female pubertal assay. In this study we examined the chlorotriazine simazine, ...

  19. PUBERTAL DEVELOPMENT IN FEMALE WISTAR RATS FOLLOWING EXPOSURE TO PROPAZINE AND ATRAZINE BIOTRANSFORMATION BY-PRODUCTS, DIAMINO-S-CHLOROTRIAZINE AND HYDROXYATRAZINE

    EPA Science Inventory

    We have shown previously that the chlorotriazine herbicide, atrazine (ATR), delays the onset of pubertal development in female rats. ATR and its by-products of microbial degradation are present in soil and groundwater. Since current maximum contaminant levels are set only for ATR...

  20. Associations among Parent-Adolescent Relationships, Pubertal Growth, Dieting, and Body Image in Young Adolescent Girls: A Short-Term Longitudinal Study.

    ERIC Educational Resources Information Center

    Archibald, Andrea Bastiani; Graber, Julia A.; Brooks-Gunn, Jeanne

    1999-01-01

    Early adolescent girls, predominantly of normal weight, were seen for 2 consecutive years and completed measures assessing their dieting, body image, and relationships with parents; weights and heights were also measured. Mothers rated daughters' pubertal growth. Findings indicated that negative parent-adolescent relationships are linked to higher…

  1. Are the Effects of Early Pubertal Timing on the Initiation of Weekly Alcohol Use Mediated by Peers and/or Parents? A Longitudinal Study

    ERIC Educational Resources Information Center

    Schelleman-Offermans, Karen; Knibbe, Ronald A.; Kuntsche, Emmanuel

    2013-01-01

    We investigated whether the link between early pubertal timing and initiation of weekly alcohol use is mediated by changes in perceived parental alcohol-specific rule setting and changes in perceived proportion of drinkers in the peer group. Longitudinal data including 3 annual waves were used to estimate the hazard for adolescents to initiate…

  2. DO BODY WEIGHT CHANGES IMPACT AGE OF PUBERTY AND REPRODUCTIVE ENDPOINTS IN THE EDSP TIER 1 MALE AND FEMALE PUBERTAL PROTOCOLS?

    EPA Science Inventory

    DO BODY WEIGHT CHANGES IMPACT AGE OF PUBERTY AND REPRODUCTIVE ENDPOINTS IN THE EDSP TIER 1 MALE AND FEMALE PUBERTAL PROTOCOLS? T.E. Stoker, K. McElroy, J. Ferrell, K. Bremser, R. Cooper and S.C. Laws. Endocrinology Branch, RTD, NHEERL, ORD, USEPA, RTP, NC.

    The relations...

  3. Relationship between Body Mass Index, Skeletal Maturation and Dental Development in 6- to 15- Year Old Orthodontic Patients in a Sample of Iranian Population

    PubMed Central

    Hedayati, Zohreh; Khalafinejad, Fatemeh

    2014-01-01

    Statement of the Problem: The prevalence of overweight and obesity has been increasing markedly in recent years. It may influence growth in pre pubertal children. Purpose: The purpose of this study was to determine whether increased Body Mass Index (BMI) is associated with accelerated skeletal maturation and dental maturation in six to fifteen years old orthodontic patients in Shiraz, Iran. Materials and Method: Skeletal maturation and dental development of 95 orthodontic patients (65 females and 30 males), aged 6 to 15 years, were determined. Dental development was assessed using the Demerjian method and skeletal maturation was evaluated by cervical vertebral method as presented by Bacetti. The BMI was determined for each patient. T-test was applied to compare the mean difference between chronologic and dental age among the study groups. A regression model was used to assess the relationship between BMI percentile, skeletal maturation, and dental development. Results: 18.9% of subjects were overweight and obese. The mean differences between dental age and chronologic age were 0.73±1.3 for underweight and normal weight children and 1.8±1.08 for overweight and obese children. These results highlighted the correlation between accelerated dental maturity and increasing BMI percentile (p= 0.002). A new formula was introduced for this relationship. There was not any significant relationship between BMI percentile and skeletal maturation. Conclusion: Children who were overweight or obese had accelerated dental development whereas they did not have accelerated skeletal maturation significantly after being adjusted for age and gender. PMID:25469357

  4. Sexual maturation in relation to polychlorinated aromatic hydrocarbons: Sharpe and Skakkebaek's hypothesis revisited.

    PubMed

    Den Hond, Elly; Roels, Harry A; Hoppenbrouwers, Karel; Nawrot, Tim; Thijs, Lutgarde; Vandermeulen, Corinne; Winneke, Gerhard; Vanderschueren, Dirk; Staessen, Jan A

    2002-08-01

    Polychlorinated aromatic hydrocarbons (PCAHs) have been described as endocrine disruptors in animals and in accidentally or occupationally exposed humans. In the present study we examined the effect of moderate exposure to PCAHs on sexual maturation. Two hundred adolescents (mean age, 17.4 years) who resided in two polluted suburbs and a rural control area in Flanders (Belgium) participated. We measured the serum concentration of polychlorinated biphenyl (PCB) congeners 138, 153, and 180 and dioxin-like compounds [chemically activated luciferase expression (CALUX) assay] as biomarkers of exposure. School physicians assessed the pubertal development of boys and girls and measured testicular volume. In one suburb near two waste incinerators, compared with the other suburb and the control area, fewer boys (p < 0.001) had reached the adult stages of genital development (62% vs. 92% and 100%, respectively) and pubic hair growth (48% vs. 77% and 100%). Also, in the same suburb, fewer girls (p = 0.04) had reached the adult stage of breast development (67% vs. 90% and 79%). In individual boys, a doubling of the serum concentration of PCB congener 138 increased the odds of not having matured into the adult stage of genital development by 3.5 (p = 0.04); similarly for PCB congener 153 in relation to male pubic hair growth, the odds ratio was 3.5 (p = 0.04). In girls, a doubling of the serum dioxin concentration increased the odds of not having reached the adult stage of breast development by 2.3 (p = 0.02). Left plus right testicular volume was lower in both polluted areas than in the control area (42.4 mL vs. 47.3 mL, p = 0.005) but was not related to the current exposure of the adolescents to PCAHs. Through endocrine disruption, environmental exposure to PCAHs may interfere with sexual maturation and in the long-run adversely affect human reproduction.

  5. Sexual maturation in relation to polychlorinated aromatic hydrocarbons: Sharpe and Skakkebaek's hypothesis revisited.

    PubMed Central

    Den Hond, Elly; Roels, Harry A; Hoppenbrouwers, Karel; Nawrot, Tim; Thijs, Lutgarde; Vandermeulen, Corinne; Winneke, Gerhard; Vanderschueren, Dirk; Staessen, Jan A

    2002-01-01

    Polychlorinated aromatic hydrocarbons (PCAHs) have been described as endocrine disruptors in animals and in accidentally or occupationally exposed humans. In the present study we examined the effect of moderate exposure to PCAHs on sexual maturation. Two hundred adolescents (mean age, 17.4 years) who resided in two polluted suburbs and a rural control area in Flanders (Belgium) participated. We measured the serum concentration of polychlorinated biphenyl (PCB) congeners 138, 153, and 180 and dioxin-like compounds [chemically activated luciferase expression (CALUX) assay] as biomarkers of exposure. School physicians assessed the pubertal development of boys and girls and measured testicular volume. In one suburb near two waste incinerators, compared with the other suburb and the control area, fewer boys (p < 0.001) had reached the adult stages of genital development (62% vs. 92% and 100%, respectively) and pubic hair growth (48% vs. 77% and 100%). Also, in the same suburb, fewer girls (p = 0.04) had reached the adult stage of breast development (67% vs. 90% and 79%). In individual boys, a doubling of the serum concentration of PCB congener 138 increased the odds of not having matured into the adult stage of genital development by 3.5 (p = 0.04); similarly for PCB congener 153 in relation to male pubic hair growth, the odds ratio was 3.5 (p = 0.04). In girls, a doubling of the serum dioxin concentration increased the odds of not having reached the adult stage of breast development by 2.3 (p = 0.02). Left plus right testicular volume was lower in both polluted areas than in the control area (42.4 mL vs. 47.3 mL, p = 0.005) but was not related to the current exposure of the adolescents to PCAHs. Through endocrine disruption, environmental exposure to PCAHs may interfere with sexual maturation and in the long-run adversely affect human reproduction. PMID:12153757

  6. Changes in the expression of Toll-like receptors in the chicken testis during sexual maturation and Salmonella infection.

    PubMed

    Anastasiadou, M; Theodoridis, A; Avdi, M; Michailidis, G

    2011-10-01

    Rooster infertility is a major concern in the poultry industry and chicken male reproductive organs are the infectious tissues of various pathogenic microorganisms. Protection of the chicken male reproductive organs from pathogens is therefore an essential aspect of reproductive physiology. Recently Toll-like receptors (TLRs) have been identified as one of the key components of innate immunity in vertebrate species and have been reported to be expressed in the reproductive organs in various female species, including the chicken. However, mechanisms of antimicrobial protection of male reproductive organs mediated by TLRs are poorly understood. The objectives of this study were to determine the expression profile of the entire family of the ten chicken TLR genes in the chicken testis, to investigate whether sexual maturation affects their testicular mRNA abundance and to determine the changes in their expression levels in response to Salmonella enteritidis (SE) infection. RNA was extracted from the testis of healthy pre-pubertal, sexually mature and aged birds, and from sexually mature SE infected birds. RT-PCR analysis revealed that all TLRs, apart from TLR1-1 (TLR6), were expressed in the chicken testis. Quantitative real-time PCR analysis revealed that the testicular mRNA abundance of certain TLRs was developmentally regulated with respect to sexual maturation, while SE infection resulted in a significant induction of TLR2-1, 4, 5, 15 and 21 in the testis of sexually mature birds compared, to healthy birds of the same age. These findings provide strong evidence to suggest a key role of TLRs in the innate immune responses of chicken testis against Salmonella colonization. PMID:21975303

  7. Maturation of Oocytes in Vitro.

    PubMed

    Lonergan, Patrick; Fair, Trudee

    2016-01-01

    Only a fraction of oocytes present in the ovaries at birth are ever ovulated during the lifetime of a female mammal. In vitro maturation (IVM) offers the possibility to exploit what is a largely untapped biological resource. Although IVM is used routinely for the in vitro production of embryos in domestic species, especially cattle, its clinical use in human-assisted reproduction is still evolving. The successful recapitulation in vitro of the events associated with successful oocyte maturation is not always achieved, with the majority of immature oocytes typically failing to develop to the blastocyst stage. Evidence suggests that although culture conditions throughout in vitro embryo production may have a modest influence on the developmental potential of the early embryo, the quality of the oocyte at the start of the process is the key factor determining the proportion of oocytes developing to the blastocyst stage.

  8. High prevalence of lipoatrophy in pre-pubertal South African children on antiretroviral therapy: a cross-sectional study

    PubMed Central

    2012-01-01

    Abstract Background Despite changes in WHO guidelines, stavudine is still used extensively for treatment of pediatric HIV in the developing world. Lipoatrophy in sub-Saharan African children can be stigmatizing and have far-reaching consequences. The severity and extent of lipoatrophy in pre-pubertal children living in sub-Saharan Africa is unknown. Methods In this cross-sectional study, children who were 3-12 years old, on antiretroviral therapy and pre-pubertal were recruited from a Family HIV Clinic in South Africa. Lipoatrophy was identified and graded by consensus between two HIV pediatricians using a standardized grading scale. A professional dietician performed formal dietary assessment and anthropometric measurements of trunk and limb fat. Previous antiretroviral exposures were recorded. In a Dual-Energy X-ray Absorbtiometry (DXA) substudy body composition was determined in 42 participants. Results Among 100 recruits, the prevalence of visually obvious lipoatrophy was 36% (95% CI: 27%–45%). Anthropometry and DXA measurements corroborated the clinical diagnosis of lipoatrophy: Both confirmed significant, substantial extremity fat loss in children with visually obvious lipoatrophy, when adjusted for age and sex. Adjusted odds ratio for developing lipoatrophy was 1.9 (95% CI: 1.3 - 2.9) for each additional year of accumulated exposure to standard dose stavudine. Cumulative time on standard dose stavudine was significantly associated with reductions in biceps and triceps skin-fold thickness (p=0.008). Conclusions The prevalence of visually obvious lipoatrophy in pre-pubertal South African children on antiretroviral therapy is high. The amount of stavudine that children are exposed to needs review. Resources are needed to enable low-and-middle-income countries to provide suitable pediatric-formulated alternatives to stavudine-based pediatric regimens. The standard stavudine dose for children may need to be reduced. Diagnosis of lipoatrophy at an early stage is

  9. Effects of bone-specific physical activity, gender and maturity on tibial cross-sectional bone material distribution: a cross-sectional pQCT comparison of children and young adults aged 5-29 years.

    PubMed

    Rantalainen, Timo; Weeks, Benjamin K; Nogueira, Rossana C; Beck, Belinda R

    2015-03-01

    Growth is the opportune time to modify bone accrual. While bone adaptation is known to be dependent on local loading and consequent deformations (strain) of bone, little is known about the effects of sex, and bone-specific physical activity on location-specific cross-sectional bone geometry during growth. To provide more insight we examined bone traits at different locations around tibial cross sections, and along the tibia between individuals who vary in terms of physical activity exposure, sex, and pubertal status. Data from 304 individuals aged 5-29 years (172 males, 132 females) were examined. Peripheral quantitative computed tomography (pQCT) was applied at 4%, 14%, 38%, and 66% of tibial length. Maturity was established by estimating age at peak height velocity (APHV). Loading history was quantified with the bone-specific physical activity questionnaire (BPAQ). Comparisons, adjusted for height, weight and age were made between sex, maturity, and BPAQ tertile groups. Few to no differences were observed between sexes or BPAQ tertiles prior to APHV, whereas marked sexual dimorphism and differences between BPAQ tertiles were observed after APHV. Cross-sectional location-specific differences between BPAQ tertiles were not evident prior to APHV, whereas clear location-specificity was observed after APHV. In conclusion, the skeletal benefits of physical activity are location-specific in the tibia. The present results indicate that the peri- or post-pubertal period is likely a more favourable window of opportunity for enhancing cross-sectional bone geometry than pre-puberty. Increased loading during the peri-pubertal period may enhance the bone of both sexes.

  10. Technology maturation process: the NASA Strategic Astrophysics Technology (SAT) program

    NASA Astrophysics Data System (ADS)

    Perez, Mario R.; Pham, Bruce T.; Lawson, Peter R.

    2014-08-01

    In 2009 the Astrophysics Division at NASA Headquarters established the Strategic Astrophysics Technology (SAT) solicitation as a new technology maturation program to fill the needed gap for mid-Technology Readiness Level (TRL) levels (3≤ TRL <6). In three full proposal selection cycles since the inception of this program, more than 40 investigations have been selected, many meritorious milestones have been met and advances have been achieved. In this paper, we review the process of establishing technology priorities, the management of technology advancements and milestones, and the incipient success of some of these investigations in light of the need of future space missions.

  11. Maturity model for enterprise interoperability

    NASA Astrophysics Data System (ADS)

    Guédria, Wided; Naudet, Yannick; Chen, David

    2015-01-01

    Historically, progress occurs when entities communicate, share information and together create something that no one individually could do alone. Moving beyond people to machines and systems, interoperability is becoming a key factor of success in all domains. In particular, interoperability has become a challenge for enterprises, to exploit market opportunities, to meet their own objectives of cooperation or simply to survive in a growing competitive world where the networked enterprise is becoming a standard. Within this context, many research works have been conducted over the past few years and enterprise interoperability has become an important area of research, ensuring the competitiveness and growth of European enterprises. Among others, enterprises have to control their interoperability strategy and enhance their ability to interoperate. This is the purpose of the interoperability assessment. Assessing interoperability maturity allows a company to know its strengths and weaknesses in terms of interoperability with its current and potential partners, and to prioritise actions for improvement. The objective of this paper is to define a maturity model for enterprise interoperability that takes into account existing maturity models while extending the coverage of the interoperability domain. The assessment methodology is also presented. Both are demonstrated with a real case study.

  12. 7 CFR 51.2651 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2651 Mature. Mature means that the cherries have reached the stage of growth which will insure the...

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

    PubMed

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

    2011-09-15

    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 adulthood. From animal studies it has become clear that sex steroids are capable of influencing brain organization, both during the prenatal period as well as during other periods characterized by massive sex steroid changes such as puberty. Here we review structural neuroimaging studies and show that the changes in sex steroids availability during puberty and adolescence might trigger a period of structural reorganization of grey and white matter in the developing human brain. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain.

  14. Influence of housing and season on pubertal development, boar taint compounds and skin lesions of male pigs.

    PubMed

    Prunier, A; Brillouët, A; Merlot, E; Meunier-Salaün, M C; Tallet, C

    2013-12-01

    Rearing entire pigs may lead to meat quality and welfare problems in relation to pubertal development. A better knowledge of the sources of variation of pubertal development, behaviour and boar taint is needed before generalizing entire male pigs. From 84 days of age, entire male pigs were reared in groups of 10 either in a conventional (C, 1 m²/animal, slatted floor) or an enriched (E, 2.5 m²/animal, straw bedding, outdoor run) housing during spring or autumn and fed ad libitum (n=10/housing/season). Mounting behaviour was observed for 3 h during the third (M3), fourth (M4) and fifth (M5) months of age. The total number of skin lesions was counted on both sides of the pigs 1 day before the behavioural recordings. The time spent in the outdoor run was also recorded during 3 days per month. The animals were slaughtered at 161±1 days of age (122±9 kg live weight). Blood samples were collected at 89 (M3), 119 (M4) and 152 (M5) days of age and at slaughter for the testosterone and oestradiol measurements. The testes were collected at slaughter, freed from the surrounding tissues and weighed. The fat samples were collected for the androstenone and skatole concentration measurement. Plasma testosterone and oestradiol-17β (oestradiol), fat androstenone and skatole and weight of the testes did not differ between the housing systems. Plasma testosterone (8.3 v. 3.9 nmol/l, P<0.05) and oestradiol (12.0 v. 9.2 pmol/l, P<0.1) at M3, fat skatole (0.124 v. 0.043, P<0.03) and weight of the testes (587 v. 512 g, P<0.05) were higher in the autumn than in the spring trial, suggesting that the pubertal development was accelerated. The number of received mounting behaviours was slightly higher in the autumn (P=0.08) trial and was markedly higher in the E than in the C environment (P<0.003). Skin lesions were more numerous in the C than in the E housing at M4 and M5 and in the spring than in the autumn trial at M3 and M4 (P<0.05). Fat androstenone and the number of performed

  15. The use of focus groups to examine pubertal concerns in preteen girls: initial findings and implications for practice and research.

    PubMed

    Doswell, W M; Vandestienne, G

    1996-01-01

    This article presents the findings of four focus groups aimed at discovering the concerns a group of 9- to 12-year-old African American and Hispanic girls (N = 38) had about puberty, the transition to adolescence, and growing up. Among the factors these girls liked about growing up were increasing independence from parents, widening social relations with same- and opposite-sex friends, and an increase in decision making regarding clothes and activities. What they reported as not liking about growing up were an increase in peer pressure, high parental expectations, and more responsibility for their actions in home, school, and recreational activities. Health care for this group must include systematic monitoring of pubertal development and concerns in order to aggressively educate preadolescents to negotiate this period smoothly and to avoid high-risk behaviors that could have negative health and social sequelae during adolescence and adulthood. PMID:8920329

  16. Effects of acute unilateral ovariectomy to pre-pubertal rats on steroid hormones secretion and compensatory ovarian responses

    PubMed Central

    2011-01-01

    In the present study we analyzed the existence of asymmetry in the secretion of steroid hormones in pre-pubertal female rats treated with unilateral ovariectomy (ULO) or unilateral perforation of the abdominal wall (sham-surgery). Treated rats were sacrificed at different times after surgery. Since sham-surgery had an apparent effect on the age of first vaginal estrous (FVE) and serum levels hormone, the results of the sham surgery groups were used to assess the effects of their respective surgery treatment groups. On the day of FVE, compensatory ovulation (CO) and compensatory ovarian hypertrophy (COH) were similar in animals with ULO, regardless of the ovary remaining in situ. In ULO treated animals, progesterone (P4) levels were higher than in animals with sham-surgery one hour after treatment but lower in rats sacrificed at FEV. Left-ULO resulted in lower testosterone (T) concentration 48 and 72 hours after surgery. In rats with Right-ULO lower T concentrations were observed in rats sacrificed one or 72 hours after surgery, and at FVE. ULO (left or right) resulted in lower estradiol (E2) concentrations one or 72 hours after treatment. In rats with Left-ULO, E2 levels were higher 48 hours after surgery and at FVE. Left-ULO resulted in higher levels of follicle stimulating hormone (FSH) five hours after surgery and at FVE. FSH levels were higher in rats with Right-ULO sacrificed on FVE. The present results suggest that in the pre-pubertal rat both ovaries have similar capacities to secrete P4, and that the right ovary has a higher capacity to secrete E2. Taken together, the present results support the idea that the effects of ULO result from the decrease in glandular tissue and changes in the neural information arising from the ovary. PMID:21450102

  17. Regulation of testicular insulin-like growth factor-I in pubertal growth hormone-deficient male rats.

    PubMed

    Spiteri-Grech, J; Bartlett, J M; Nieschlag, E

    1991-11-01

    GH plays a major role in pubertal growth, effects mainly mediated by stimulation of insulin-like growth factor-I (IGF-I) production by the liver. However, the role of GH in the regulation of pubertal onset, spermatogenesis and fertility is still under debate. GH and FSH have, in addition, been implicated in the regulation of IGF-I production by Sertoli cells in a number of studies, although conflicting results have been reported. The interpretation of studies using GH-deficient mutant mice has been complicated by the presence of additional defects in the hypothalamic-pituitary-gonadal axis of these animals. We have therefore used GH-deficient mutant male rats with no other documented hormonal deficiencies to study the effect of GH administration on somatic and testicular development, circulating and testicular IGF-I concentrations and testicular histology. Body weights in GH-deficient rats substituted with GH were not significantly different from untreated or GH-treated normal rats and were significantly higher than body weights in untreated dwarf rats. Similarly, circulating IGF-I concentrations in GH-treated GH-deficient rats were not significantly different from those in untreated or GH-treated normal rats but were significantly higher than circulating IGF-I concentrations in untreated dwarf rats. No differences in testicular IGF-I concentrations were observed in any of the groups studied. Testicular weights remained low in both untreated and GH-treated GH-deficient animals compared with control animals but spermatogenesis was qualitatively and quantitatively normal in all groups at the end of the observation period.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    USGS Publications Warehouse

    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.

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

    PubMed

    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.

  20. Association of dietary energy density in childhood with age and body fatness at the onset of the pubertal growth spurt.

    PubMed

    Günther, Anke L B; Stahl, Lisa J; Buyken, Anette E; Kroke, Anja

    2011-08-01

    The aim of the present study was to examine the association of pre-pubertal dietary energy density (ED) with both age and body fatness at the start of the pubertal growth spurt (age at take-off, ATO). Analyses included 219 DOrtmund Nutritional and Anthropometric Longitudinally Designed Study participants with sufficient height measurements to estimate ATO who provided 3 d weighed dietary records at baseline, i.e. 2 and 3 years before ATO (mean age 6·9 (SD 1·2) years). Mean energy intakes and amounts of foods/drinks consumed at baseline were derived from the records. ED (kJ/g) was calculated based on (1) all foods and drinks (ED_all), (2) foods and energy-containing drinks (ED_energy), (3) foods and milk as a drink, but no other beverages (ED_milk) and (4) foods only, solid or liquid (ED_food). Using multiple regression analyses, the association between the ED variables and ATO was investigated. Furthermore, Z-scores of BMI and fat mass index (FMI) at ATO were considered as outcomes to reflect body fatness at puberty onset. The results showed that ED at baseline was not associated with ATO, regardless of the ED method used. For example, mean ATO in the lowest v. highest tertile of ED_food was 9·3 (95 % CI 9·0, 9·5) v. 9·4 (95 % CI 9·1, 9·7) years, P(trend) = 0·8 (adjusted for sex, maternal age, birth weight, dietary protein, dietary fibre, baseline BMI Z-score). Similarly, ED was not independently associated with BMI or FMI Z-score at ATO (P(trend) = 0·3-0·9). In conclusion, dietary ED in childhood did not influence timing or body fatness at ATO in this cohort of healthy, free-living children. PMID:21736806

  1. Deslorelin implants in pre-pubertal female dogs: short- and long-term effects on the genital tract.

    PubMed

    Marino, G; Rizzo, S; Quartuccio, M; Macrì, F; Pagano, G; Taormina, A; Cristarella, S; Zanghì, A

    2014-04-01

    Deslorelin acetate is a GnRH agonist used for contraception in dogs. This study aimed to evaluate the treatment of pre-pubertal female dogs with deslorelin acetate implants, to better investigate the primary stimulatory effect of the drug and the long-term effects on the genital tract, throughout repeated treatments. Sicilian hound female dogs (24) were randomly assigned to treated group, control group 1 and control group 2. First group bitches were implanted at 4.5, 9.0 and 13.5 months and monitored clinically, ultrasonographically and endocrinologically, throughout the study period (13.5 months). Control group 1 bitches were not implanted and clinically monitored for the same period. At 18 months, the animals underwent ovariohysterectomy, thus allowing evaluation of the internal genitalia. Control group 2 bitches were ovariohysterectomized at the age of 4.5 months. The suppression of oestrus was obtained in the treated group despite the fact that the first implant caused a modest increase in plasmatic levels of 17-beta estradiol and an evident cornification of the vaginal mucosa cells (50-80%). Estradiol and progesterone were at baseline levels for the remaining study period, in which no other oestrous manifestations were observed. The external genitalia maintained a juvenile appearance. The ovaries, ultrasonographically, showed no follicular structures and stayed the same size. At 18 months, the genital tract was still juvenile with inactive small ovaries and a thin filiform uterus. Deslorelin suppressed ovarian activity in pre-pubertal bitches, and oestrous induction was not observed despite the presence of the primary stimulatory effect of the drug. Juvenile genitalia were an expected side effect of the treatment. PMID:24467617

  2. Manic depressive psychosis and schizophrenia are neurological disorders at the extremes of CNS maturation and nutritional disorders associated with a deficit in marine fat.

    PubMed

    Saugstad, L F

    2001-12-01

    The maturational theory of brain development comprises manic depressive psychosis and schizophrenia. It holds that the disorders are part of human diversity in growth and maturation, which explains their ubiquity, shared susceptibility genes and multifactorial inheritance. Rate of maturation and age at puberty are the genotype; the disorders are localized at the extremes with normality in between. This is based on the association between onset of puberty and the final regressive event, with pruning of 40% of excitatory synapses leaving the inhibitory ones fairly unchanged. This makes excitability, a fundamental property of nervous tissue, a distinguishing factor: the earlier puberty, the greater excitability--the later puberty, the greater deficit. Biological treatment supports deviation from the norm: neuroleptics are convulsant; antidepressives are anti-epiletogenic. There is an association between onset of puberty and body-build: early maturers are pyknic broad-built, late ones linearly leptosomic. This discrepancy is similar to that in the two disorders, supporting the theory that body-build is the phenotype. Standard of living is the environmental factor, which affects pubertal age and shifts the panorama of mental illness accordingly. Unnatural death has increased with antipsychotics. Other treatment is needed. PUFA deficit has been observed in RBC in both disorders and striking improvements with addition of minor amounts of PUFA. This supports that dietary deficit might cause psychotic development and that prevention is possible. Other neurological disorders also profit from PUFA, underlining a general deficit in the diet.

  3. Correlation of calcification of permanent mandibular canine, mandibular premolars, and permanent mandibular first and second molars with skeletal maturity in Indian population

    PubMed Central

    Motghare, Pawan C.; Bedia, Aarti S.; Degwekar, Shirish S.; Indurkar, Atul D.; Bedia, Sumit

    2016-01-01

    Context: Morphological variation in children can be understood by the knowledge of growth and development. The state of dental development can be used in forensic odontology to ascertain the age of an unidentified child. Aims: This study aims to investigate the relationship of the stages of calcification of the permanent mandibular canine, mandibular premolars, and permanent mandibular first and second molars with skeletal maturity using panoramic and hand–wrist radiographs. Settings and Design: This descriptive work was designed as a cross-sectional study. Materials and Methods: The study was conducted on 300 healthy subjects (150 males and 150 females) ranging 7–20 years of age. Demirjian's method and Björk, Grave, and Brown's method were used to correlate teeth calcification and skeletal maturity, respectively. Statistical Analysis Used: Descriptive statistics and Spearman's rank correlation coefficient were used. Results: 1. Correlation coefficients between the skeletal maturity stages and the developmental stages of the five teeth ranged 0.461–0.877 for females and 0.480–0.790 for males. 2. The second molar showed the highest and the first molar showed the lowest relationship for female and male subjects in the Indian population. Conclusions: The findings of this study indicate that tooth calcification stages might be clinically used as a maturity indicator of the pubertal growth period. PMID:27555721

  4. 7 CFR 51.1904 - Maturity classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Maturity classification. 51.1904 Section 51.1904... STANDARDS) United States Consumer Standards for Fresh Tomatoes Size and Maturity Classification § 51.1904 Maturity classification. Tomatoes which are characteristically red when ripe, but are not overripe or...

  5. 7 CFR 51.1904 - Maturity classification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Maturity classification. 51.1904 Section 51.1904 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Maturity Classification § 51.1904 Maturity classification. Tomatoes which are characteristically red...

  6. 7 CFR 51.1904 - Maturity classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Maturity classification. 51.1904 Section 51.1904... STANDARDS) United States Consumer Standards for Fresh Tomatoes Size and Maturity Classification § 51.1904 Maturity classification. Tomatoes which are characteristically red when ripe, but are not overripe or...

  7. Career Maturity in High School Age Females.

    ERIC Educational Resources Information Center

    Pedro, Joan Daniels

    1982-01-01

    Examined career maturity in high school females by using a set of general career-maturity and gender-specific, career-related measures, and an alternate career-maturity criterion measure, career-planning involvement. Results indicated significant relationships between achievement orientation and occupational information and knowledge of women's…

  8. Toward a Concept of Psychosocial Maturity.

    ERIC Educational Resources Information Center

    Greenberger, Ellen; Sorensen, Aage B.

    The first in a series of related reports (see TM 000 775), this paper attempts to define a concept of psychosocial maturity which would be appropriate as a comprehensive educational goal. Biological, sociological, psychological and temporal formulations of maturity are discussed and compared. Am interdisciplinary model of maturity is evolved which…

  9. 7 CFR 51.1904 - Maturity classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Maturity classification. 51.1904 Section 51.1904... STANDARDS) United States Consumer Standards for Fresh Tomatoes Size and Maturity Classification § 51.1904 Maturity classification. Tomatoes which are characteristically red when ripe, but are not overripe or...

  10. Sport injuries aligned to peak height velocity in talented pubertal soccer players.

    PubMed

    van der Sluis, A; Elferink-Gemser, M T; Coelho-e-Silva, M J; Nijboer, J A; Brink, M S; Visscher, C

    2014-04-01

    In young athletes, demands of sports are superimposed on normal growth and maturation. It has been suggested that this causes a temporarily increased vulnerability for injuries. We followed 26 talented soccer players (mean age 11.9±0.84 years) longitudinally for 3 years around their adolescent growth spurt, called Peak Height Velocity, to identify differences in number of traumatic and overuse injuries and days missed due to injuries. Peak Height Velocity was calculated according to the Maturity Offset Protocol. The number of injuries was calculated for each player per year. A repeated measurement analysis showed that athletes had significantly more traumatic injuries in the year of Peak Height Velocity (1.41) than in the year before Peak Height Velocity (0.81). A moderate effect size of 0.42 was found for the difference in number of overuse injuries per player per year before (0.81) and after Peak Height Velocity (1.41), respectively. Finally, a moderate effect size of 0.55 was found for difference between days missed due to injuries before (7.27 days per player per year) and during Peak Height Velocity (15.69 days per player per year). Adolescent growth spurt seems to result in increased vulnerability for traumatic injuries. Afterwards athletes seem to be susceptible to overuse injuries.

  11. Estrus synchronization in beef heifers with progestin-based protocols. I. Differences in response based on pubertal status at the initiation of treatment.

    PubMed

    Wood-Follis, S L; Kojima, F N; Lucy, M C; Smith, M F; Patterson, D J

    2004-11-01

    Two progestin-based protocols for estrus synchronization in replacement beef heifers were compared on the basis of estrous response, interval to and synchrony of estrus, and pregnancy rate. The objective was to determine, whether addition of GnRH to a melengestrol acetate (MGA)-prostaglandin F2alpha (PGF2alpha) estrus synchronization protocol would improve synchrony of estrus without compromising fertility in yearling beef heifers. Heifers at two locations (Location 1, n = 60 and Location 2, n = 64) were assigned randomly to one of two treatments by breed and pubertal status. Heifers were defined as, pubertal when concentrations of progesterone in serum were elevated (> or = 1 ng/mL) in either one of two samples obtained 10 and 1 day prior to treatment initiation. Prior to MGA administration, 18/60 (30%) and 36/64 (56%) of the heifers at Locations 1 and 2, respectively, were pubertal. Heifers in both treatments were fed MGA (0.5 mg/head/day in 1.8 kg/head/day supplement) for 14 days followed by 25 mg of PGF2alpha i.m. (MGA-PGF2alpha) 19 days after MGA withdrawal (Day 33 of treatment). One-half of the heifers at each location received 100 microg of GnRH i.m. 12 days after MGA withdrawal (Day 26 of treatment; MGA Select). The control group received only MGA-PGF2alpha. Heifers were observed for signs of behavioral estrus continuously during daylight hours for 7 days beginning on the day PGF2alpha was administered. Heifers were inseminated 12 h after observed estrus. There was a treatment by location by pubertal status interaction (P < 0.05) for interval to estrus. Compared to the respective control treatment at each location, prepubertal heifers assigned to the MGA Select protocol at Location 1 had longer intervals to estrus, whereas at Location 2, prepubertal heifers assigned to the MGA-PGF2alpha protocol had longer intervals to estrus. The higher number of pubertal heifers at Location 2 was associated with a reduced variance in the interval to estrus among MGA

  12. Can Age at Sexual Maturity act as a Predictive Biomarker for prodromal negative symptoms?

    PubMed Central

    Ramanathan, Seethalakshmi; Miewald, Jean; Montrose, Debra; Keshavan, Matcheri S

    2015-01-01

    Background Puberty and reproductive hormones have been identified as having a potential role in schizophrenia. Earlier reports have suggested associations between later age at puberty and schizophrenia in males. Similarly, associations have been reported between testosterone levels and psychotic symptoms. In this report, we examined the association between age at puberty and prodromal symptoms of psychosis. Methods 58 child or adolescent family members of individuals with schizophrenia were interviewed using the Scale of Prodromal Symptoms and the Tanner Maturational Scale. Age at tanner pubertal stage was determined and regression analyses were used to explore associations between prodromal symptoms and age at puberty. Results Among males, delayed age at puberty was associated with greater severity of prodromal symptoms; the association between negative prodromal symptoms and delayed age was significant (p=0.001). In females, the association was not statistically significant. Conclusions Our results suggest that delayed age at puberty may be associated with negative prodromal symptoms of schizophrenia in males. Our findings suggest that delayed age at puberty could potentially be a predictive biomarker for psychopathology in males at risk for schizophrenia. PMID:25778616

  13. Bile acid-FXRα pathways regulate male sexual maturation in mice

    PubMed Central

    Vega, Aurélie; Sédes, Lauriane; Rouaisnel, Betty; de Haze, Angélique; Baron, Silvère; Schoonjans, Kristina; Caira, Françoise; Volle, David H.

    2016-01-01

    The bile acid receptor Farnesol-X-Receptor alpha (FRXα) is a member of the nuclear receptor superfamily. FRXα is expressed in the interstitial compartment of the adult testes, which contain the Leydig cells. In adult, short term treatment (12 hours) with FRXα agonist inhibits the expression of steroidogenic genes via the induction of the Small heterodimer partner (SHP). However the consequences of FRXα activation on testicular pathophysiology have never been evaluated. We demonstrate here that mice fed a diet supplemented with bile acid during pubertal age show increased incidence of infertility. This is associated with altered differentiation and increase apoptosis of germ cells due to lower testosterone levels. At the molecular level, next to the repression of basal steroidogenesis via the induction expression of Shp and Dax-1, two repressors of steroidogenesis, the main action of the BA-FRXα signaling is through lowering the Leydig cell sensitivity to the hypothalamo-pituitary axis, the main regulator of testicular endocrine function. In conclusion, BA-FRXα signaling is a critical actor during sexual maturation. PMID:26848619

  14. Bile acid-FXRα pathways regulate male sexual maturation in mice.

    PubMed

    Baptissart, Marine; Martinot, Emmanuelle; Vega, Aurélie; Sédes, Lauriane; Rouaisnel, Betty; de Haze, Angélique; Baron, Silvère; Schoonjans, Kristina; Caira, Françoise; Volle, David H

    2016-04-12

    The bile acid receptor Farnesol-X-Receptor alpha (FRXα) is a member of the nuclear receptor superfamily. FRXα is expressed in the interstitial compartment of the adult testes, which contain the Leydig cells. In adult, short term treatment (12 hours) with FRXα agonist inhibits the expression of steroidogenic genes via the induction of the Small heterodimer partner (SHP). However the consequences of FRXα activation on testicular pathophysiology have never been evaluated. We demonstrate here that mice fed a diet supplemented with bile acid during pubertal age show increased incidence of infertility. This is associated with altered differentiation and increase apoptosis of germ cells due to lower testosterone levels. At the molecular level, next to the repression of basal steroidogenesis via the induction expression of Shp and Dax-1, two repressors of steroidogenesis, the main action of the BA-FRXα signaling is through lowering the Leydig cell sensitivity to the hypothalamo-pituitary axis, the main regulator of testicular endocrine function. In conclusion, BA-FRXα signaling is a critical actor during sexual maturation. PMID:26848619

  15. The Relationship Between Cognitive Career Maturity and Self-Reported Career Maturity of High School Students.

    ERIC Educational Resources Information Center

    Westbrook, Bert W.; And Others

    1987-01-01

    Investigated relationship between scores on measures of cognitive career maturity and self-reported career maturity in high school sophomores (N=391) and juniors (N=283). Results suggest that there is no relationship between measured career maturity competencies and self-reported career maturity competencies of high school students. (Author/NB)

  16. Effects of Low-Dose Estrogen Replacement During Childhood on Pubertal Development and Gonadotropin Concentrations in Patients With Turner Syndrome: Results of a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

    PubMed Central

    Wan, Xiaohai; Garg, Sipi; Kowal, Karen; Cutler, Gordon B.; Ross, Judith L.

    2014-01-01

    Context: The optimal approach to estrogen replacement in girls with Turner syndrome has not been determined. Objective: The aim of the study was to assess the effects of an individualized regimen of low-dose ethinyl estradiol (EE2) during childhood from as early as age 5, followed by a pubertal induction regimen starting after age 12 and escalating to full replacement over 4 years. Design: This study was a prospective, randomized, double-blind, placebo-controlled clinical trial. Setting: The study was conducted at two US pediatric endocrine centers. Subjects: Girls with Turner syndrome (n = 149), aged 5.0–12.5 years, were enrolled; data from 123 girls were analyzable for pubertal onset. Intervention(s): Interventions comprised placebo or recombinant GH injections three times a week, with daily oral placebo or oral EE2 during childhood (25 ng/kg/d, ages 5–8 y; 50 ng/kg/d, ages >8–12 y); after age 12, all patients received escalating EE2 starting at a nominal dosage of 100 ng/kg/d. Placebo/EE2 dosages were reduced by 50% for breast development before age 12 years, vaginal bleeding before age 14 years, or undue advance in bone age. Main Outcome Measures: The main outcome measures for this report were median ages at Tanner breast stage ≥2, median age at menarche, and tempo of puberty (Tanner 2 to menarche). Patterns of gonadotropin secretion and impact of childhood EE2 on gonadotropins also were assessed. Results: Compared with recipients of oral placebo (n = 62), girls who received childhood low-dose EE2 (n = 61) had significantly earlier thelarche (median, 11.6 vs 12.6 y, P < 0.001) and slower tempo of puberty (median, 3.3 vs 2.2 y, P = 0.003); both groups had delayed menarche (median, 15.0 y). Among childhood placebo recipients, girls who had spontaneous breast development before estrogen exposure had significantly lower median FSH values than girls who did not. Conclusions: In addition to previously reported effects on cognitive measures and GH

  17. Sexual maturation of female Saguinus oedipus oedipus

    SciTech Connect

    Tardif, S.D.

    1982-01-01

    This study is an examination of the process of female sexual maturation in the cotton-top tamarin, Saguinus oedipus oedipus, a South-American primate of the family, Callitrichidae. Two types of questions are addressed. The first question is whether the type of social grouping in which a young female lives affects the rate of her sexual maturation. Specifically, is there a difference between the maturation rate of a female housed with a strange adult male and a female housed with her natal group (i.e., her parents and various siblings). Second, the effect of sexual maturation on various social interactions is examined. Specifically are male-female interactions in mated pairs and mother-daughter interactions in natal groups changed by the sexual maturation of the young females. The mother's presence was not related to the daughter's maturation age. However, whether the natal group, as a whole, inhibited maturation, or unrelated males accelerated maturation, or both, remains unknown. Most of the behavioral interactions involving maturing females were unchanged by maturation. There was some indication that certain behaviors were affected by maturation, but only if a strange unrelated male was present.

  18. Membrane remodeling during reticulocyte maturation

    PubMed Central

    Liu, Jing; Guo, Xinhua; Mohandas, Narla; Chasis, Joel A.

    2010-01-01

    The transition of reticulocytes into erythrocytes is accompanied by extensive changes in the structure and properties of the plasma membrane. These changes include an increase in shear resistance, loss of surface area, and acquisition of a biconcave shape. The processes by which these changes are effected have remained largely undefined. Here we examine how the expression of 30 distinct membrane proteins and their interactions change during murine reticulocyte maturation. We show that tubulin and cytosolic actin are lost, whereas the membrane content of myosin, tropomyosin, intercellular adhesion molecule-4, glucose transporter-4, Na-K-ATPase, sodium/hydrogen exchanger 1, glycophorin A, CD47, Duffy, and Kell is reduced. The degradation of tubulin and actin is, at least in part, through the ubiquitin-proteasome degradation pathway. In regard to the protein-protein interactions, the formation of membrane-associated spectrin tetramers from dimers is unperturbed, whereas the interactions responsible for the formation of the membrane-skeletal junctions are weaker in reticulocytes, as is the attachment of transmembrane proteins to these structures. This weakness, in part, results from the elevated phosphorylation of 4.1R in reticulocytes, which leads to a decrease in shear resistance by reducing its interaction with spectrin and actin. These observations begin to unravel the mechanistic basis of crucial changes accompanying reticulocyte maturation. PMID:20038785

  19. Space Mission Concept Development Using Concept Maturity Levels

    NASA Technical Reports Server (NTRS)

    Wessen, Randii R.; Borden, Chester; Ziemer, John; Kwok, Johnny

    2013-01-01

    Over the past five years, pre-project formulation experts at the Jet Propulsion Laboratory (JPL) has developed and implemented a method for measuring and communicating the maturity of space mission concepts. Mission concept development teams use this method, and associated tools, prior to concepts entering their Formulation Phases (Phase A/B). The organizing structure is Concept Maturity Level (CML), which is a classification system for characterizing the various levels of a concept's maturity. The key strength of CMLs is the ability to evolve mission concepts guided by an incremental set of assessment needs. The CML definitions have been expanded into a matrix form to identify the breadth and depth of analysis needed for a concept to reach a specific level of maturity. This matrix enables improved assessment and communication by addressing the fundamental dimensions (e.g., science objectives, mission design, technical risk, project organization, cost, export compliance, etc.) associated with mission concept evolution. JPL's collaborative engineering, dedicated concept development, and proposal teams all use these and other CML-appropriate design tools to advance their mission concept designs. This paper focuses on mission concept's early Pre-Phase A represented by CMLs 1- 4. The scope was limited due to the fact that CMLs 5 and 6 are already well defined based on the requirements documented in specific Announcement of Opportunities (AO) and Concept Study Report (CSR) guidelines, respectively, for competitive missions; and by NASA's Procedural Requirements NPR 7120.5E document for Projects in their Formulation Phase.

  20. Sexual maturation in kokanee Oncorhynchus nerka

    USGS Publications Warehouse

    Patterson, S.D.; Scarnecchia, D.L.; Congleton, J.L.

    2008-01-01

    We used observational and experimental approaches to obtain information on factors affecting the timing of maturation of kokanee Oncorhynchus nerka, a semelparous, landlocked salmon. Gonadal staging criteria were developed and applied to three kokanee populations in Idaho lakes and reservoirs. Testes were classified into three stages: immature (stage one, S1), maturing (S2), and mature (S3). Ovaries were classified into eight stages: immature (S1-S3), transitional (stage S4), maturing (S5-S7), and mature (S8). Males entered the maturing stage (S2) in February through April of the spawning year. Females entered maturing stage (S5) as early as July of the year before the spawning year, and as late as March of the spawning year. Three hatchery experiments demonstrated that attainment of a larger body size 10 to 16 months before spawning increased the likelihood of initiation of maturation in both sexes. No gonads in a state of regression were observed. A gonadosomatic index above 0.1 by early July was a good indicator of a maturing male, and a gonadosomatic index above 1.0 by early July was a good indicator of a maturing female. Instantaneous growth rates were not good predictors of maturation, but attaining a size threshold of 18 to 19 cm in the fall was a good predictor of maturation the following year. This improved knowledge of kokanee maturation will permit more effectively management of the species for age, growth and size at maturity as well as for contributions to fisheries. ?? 2008 by the Northwest Scientific Association. All rights reserved.

  1. Pubertal growth of the medial amygdala delayed by short photoperiods in the Siberian hamster, Phodopus sungorus.

    PubMed

    Cooke, Bradley M; Jordan, Cynthia L; Breedlove, S Marc

    2007-09-01

    We investigated whether puberty influences the morphology of the medial nucleus of the amygdala (MeA) by comparing Siberian hamsters (Phodopus sungorus) that had been raised from birth in either long day (LD; 16:8 h light:dark) or short day (SD; 8:16) photoperiods. Hamsters were sacrificed at 42-49 days of age, at which point all LD hamsters were reproductively mature, as evidenced by adult-like testes weights (mean: 657 mg). In contrast, the testes weights of the SD hamsters were low (mean: 31 mg), indicating that the SD photoperiod had delayed puberty. The regional volume and mean soma size of the four MeA subnuclei was estimated bilaterally by stereological procedures. In the posterior dorsal and ventral MeA subnuclei, regional volume was 22-25% larger, and mean soma size 18% larger, in LD males than SD males. Unbiased cell counts in the posterior dorsal MeA showed that LD and SD hamsters have equivalent neuron numbers. In the anterior MeA subnuclei, regional volumes and soma sizes from LD and SD hamsters were equivalent. Additionally, the regional volume of the posteroventral subnucleus was larger in the right hemisphere than the left, but this laterality did not respond to photoperiod manipulation. These results suggest that the extant neurons within the posterior MeA, a steroid-sensitive nucleus implicated in socio-sexual behavior, grow in response to the elevated levels of circulating androgen accompanying puberty, and that photoperiodic regulation of puberty affects morphological maturation of this nucleus.

  2. Longitudinal changes in the time parents spend in activities with their adolescent children as a function of child age, pubertal status, and gender.

    PubMed

    Dubas, Judith Semon; Gerris, Jan R M

    2002-12-01

    This study examined the time Dutch mothers (N = 301) and fathers (N = 255) spend per day engaging in 4 activities (going somewhere, doing something, watching TV, and eating together) with their adolescent children both concurrently and 5 years later. Also assessed was whether parent-child shared time was related to parent or child gender and whether age-related differences could be explained by adolescent pubertal status, family conflict, adolescent and parent work or volunteer hours, parental work stress, and adolescent computer use. Finally, the study examined whether family conflict predicted changes in shared time and whether shared time predicted changes in conflict. The findings showed that age changes depended on the activity and that pubertal status mediated age differences in TV viewing among mixed-gender parent-child pairs. Shared time during pre-, early, and mid-adolescence was linked to decreases in family conflict 5 years later.

  3. Diethylhexyl phthalate exposure impairs follicular development and affects oocyte maturation in the mouse.

    PubMed

    Zhang, Xi-Feng; Zhang, Lian-Jun; Li, Lan; Feng, Yan-Ni; Chen, Bo; Ma, Jin-Mei; Huynh, Evanna; Shi, Qing-Hua; De Felici, Massimo; Shen, Wei

    2013-06-01

    Diethylhexyl phthalate (DEHP) is an estrogen-like compound widely used as a commercial plasticizer and present in medical devices, tubing, food containers and packaging. It is considered an endocrine disruptor and studies on experimental animals showed that exposure to DEHP can alter the function of several organs including liver, kidneys, lungs and reproductive system, particularly the developing testes of prenatal and neonatal males. Exposure to DEHP has been proposed as a potential human health hazard. This study assessed the effects of DEHP on folliculogenesis and oocyte maturation using the mouse as the experimental model. Newborn female mice were hypodermically injected with DEHP at doses of 20 and 40 μg/kg per body weight following different exposure regimens during the weaning period. We found that DEHP altered both folliculogenesis and oocyte development. In particular, DEHP exposure significantly decreased the number of the primordial follicles at pubertal and adult age by possibly accelerating the rate of follicle recruitment dynamics, reduced and/or delayed the level of imprinted gene methylation in the oocytes and increased metaphase II spindle abnormalities in oocytes matured in vitro. Furthermore, the weight of pups and litter size of mothers exposed to DEHP were significantly lower than controls. Finally, the number of primordial follicles appeared significantly reduced also in the F1 offspring at the adult age. These results show that DEHP may have a number of adverse effects on oogenesis, especially when exposure occurs during early postnatal age, arising concerns about the exposure of human female infants and children to this compound.

  4. Differences in biological maturation, anthropometry and physical performance between playing positions in youth team handball.

    PubMed

    Matthys, Stijn P J; Fransen, Job; Vaeyens, Roel; Lenoir, Matthieu; Philippaerts, Renaat

    2013-01-01

    It was the goal of this cross-sectional study to examine differences in maturity, anthropometry and physical performance between youth handball players across different playing positions (i.e. goalkeeper, back, pivot and wing). Multivariate analysis of covariance (MANCOVA), accounting for biological maturation, was used to assess positional differences in 472 male youth handball players from three age groups: U14, U15 and U16. Differences in age at peak height velocity were found in all age groups. Backs were significantly more mature than wings in U14 and U15 and than wings and pivots in U16. Furthermore, backs are overall taller, have a bigger arm span and perform best on tests for strength, agility and speed, especially in the U15 age group. Therefore, it can be concluded that youth players with the most advanced maturation status and the most favourable anthropometry and physical fitness scores, are consistently positioned in the back position. Players with a less advanced maturity status and an overall smaller stature are placed on the wing or pivot positions. In conclusion, it seems that anthropometrical and maturational characteristics are used by coaches to directly and/or indirectly select players for specific field positions. This strategy is risky since anthropometry and maturity status change over the years.

  5. Differences in biological maturation, anthropometry and physical performance between playing positions in youth team handball.

    PubMed

    Matthys, Stijn P J; Fransen, Job; Vaeyens, Roel; Lenoir, Matthieu; Philippaerts, Renaat

    2013-01-01

    It was the goal of this cross-sectional study to examine differences in maturity, anthropometry and physical performance between youth handball players across different playing positions (i.e. goalkeeper, back, pivot and wing). Multivariate analysis of covariance (MANCOVA), accounting for biological maturation, was used to assess positional differences in 472 male youth handball players from three age groups: U14, U15 and U16. Differences in age at peak height velocity were found in all age groups. Backs were significantly more mature than wings in U14 and U15 and than wings and pivots in U16. Furthermore, backs are overall taller, have a bigger arm span and perform best on tests for strength, agility and speed, especially in the U15 age group. Therefore, it can be concluded that youth players with the most advanced maturation status and the most favourable anthropometry and physical fitness scores, are consistently positioned in the back position. Players with a less advanced maturity status and an overall smaller stature are placed on the wing or pivot positions. In conclusion, it seems that anthropometrical and maturational characteristics are used by coaches to directly and/or indirectly select players for specific field positions. This strategy is risky since anthropometry and maturity status change over the years. PMID:23656188

  6. Smart Grid Interoperability Maturity Model Beta Version

    SciTech Connect

    Widergren, Steven E.; Drummond, R.; Giroti, Tony; Houseman, Doug; Knight, Mark; Levinson, Alex; longcore, Wayne; Lowe, Randy; Mater, J.; Oliver, Terry V.; Slack, Phil; Tolk, Andreas; Montgomery, Austin

    2011-12-02

    The GridWise Architecture Council was formed by the U.S. Department of Energy to promote and enable interoperability among the many entities that interact with the electric power system. This balanced team of industry representatives proposes principles for the development of interoperability concepts and standards. The Council provides industry guidance and tools that make it an available resource for smart grid implementations. In the spirit of advancing interoperability of an ecosystem of smart grid devices and systems, this document presents a model for evaluating the maturity of the artifacts and processes that specify the agreement of parties to collaborate across an information exchange interface. You are expected to have a solid understanding of large, complex system integration concepts and experience in dealing with software component interoperation. Those without this technical background should read the Executive Summary for a description of the purpose and contents of the document. Other documents, such as checklists, guides, and whitepapers, exist for targeted purposes and audiences. Please see the www.gridwiseac.org website for more products of the Council that may be of interest to you.

  7. Waste-to-energy industry maturing

    SciTech Connect

    Marier, D.

    1987-09-01

    The rapidly developing waste-to-energy industry is showing that it is offering some very real solutions to their waste-disposal problems. A recent survey showed that there were 196 resource recovery facilities, having a combined processing capacity of 156,000 tons per day (TPD), either operating, under construction, or in the advanced planning stages in the US at this time. There are growing indications, however, that the industry is already moving from the early gold rush days to the maturation stage. There is also increasing environmental opposition as the not-in-my-backyard syndrome spreads and as environmental groups increase their activities. There is every indication that politics will continue to play an important role in waste management decisions. Changing economics can also have their effect. While projects may be delayed or postponed indefinitely, there is no doubt that the waste-to-energy industry will continue to bring plants on-line. A review of 9 contract award announcements and new plant dedications is made.

  8. Arnold Gesell and the maturation controversy.

    PubMed

    Dalton, Thomas C

    2005-01-01

    This article examines the work of Arnold Lucius Gesell and argues that he not only paved the way for contemporary research in motor development, but that he and colleagues anticipated fundamental issues about growth that must be addressed by psychologists and neuroscientists who are committed to the advancement of developmental science. Arnold Lucius Gesell was a pioneer in developmental psychology when the field was in its infancy. He worked diligently for the rights of physically and mentally handicapped children to receive special education that would enable them to find gainful employment. Gesell's writings in books and popular magazines increased public awareness of and support for preschool education and better foster care for orphans. Despite these achievements, many of his successors have questioned his views about infant development. Developmental psychologists have criticized Gesell for proposing a stage theory of infant growth that has fallen into disfavor among contemporary researchers. His conception of development as a maturational process has been challenged for allegedly reducing complex behavioral, perceptual, and learning processes to genetic factors. The author rejects this overly simplistic interpretation and contends that Gesell's work continues to stand the test of time.

  9. Sterols in spermatogenesis and sperm maturation.

    PubMed

    Keber, Rok; Rozman, Damjana; Horvat, Simon

    2013-01-01

    Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its intermediates, differs vastly between the male reproductive system and nongonadal tissues. Accumulation of cholesterol precursors such as testis meiosis-activating sterol and desmosterol is observed in testes and spermatozoa from several mammalian species. Moreover, cholesterogenic genes, especially meiosis-activating sterol-producing enzyme cytochrome P450 lanosterol 14α-demethylase, display stage-specific expression patterns during spermatogenesis. Discrepancies in gene expression patterns suggest a complex temporal and cell-type specific regulation of sterol compounds during spermatogenesis, which also involves dynamic interactions between germ and Sertoli cells. The functional importance of sterol compounds in sperm production is further supported by the modulation of sterol composition in spermatozoal membranes during epididymal transit and in the female reproductive tract, which is a prerequisite for successful fertilization. However, the exact role of sterols in male reproduction is unknown. This review discusses sterol dynamics in sperm maturation and describes recent methodological advances that will help to illuminate the complexity of sperm formation and function.

  10. Arnold Gesell and the maturation controversy.

    PubMed

    Dalton, Thomas C

    2005-01-01

    This article examines the work of Arnold Lucius Gesell and argues that he not only paved the way for contemporary research in motor development, but that he and colleagues anticipated fundamental issues about growth that must be addressed by psychologists and neuroscientists who are committed to the advancement of developmental science. Arnold Lucius Gesell was a pioneer in developmental psychology when the field was in its infancy. He worked diligently for the rights of physically and mentally handicapped children to receive special education that would enable them to find gainful employment. Gesell's writings in books and popular magazines increased public awareness of and support for preschool education and better foster care for orphans. Despite these achievements, many of his successors have questioned his views about infant development. Developmental psychologists have criticized Gesell for proposing a stage theory of infant growth that has fallen into disfavor among contemporary researchers. His conception of development as a maturational process has been challenged for allegedly reducing complex behavioral, perceptual, and learning processes to genetic factors. The author rejects this overly simplistic interpretation and contends that Gesell's work continues to stand the test of time. PMID:17549936

  11. Adolescent Anovulation: Maturational Mechanisms and Implications

    PubMed Central

    2013-01-01

    Context: Adolescents are at high risk for menstrual dysfunction. The diagnosis of anovulatory disorders that may have long-term health consequences is too often delayed. Evidence Acquisition: A review of the literature in English was conducted, and data were summarized and integrated from the author's perspective. Main Findings: Normal adolescent anovulation causes only minor menstrual cycle irregularity: most cycles range from 21–45 days, even in the first postmenarcheal year, 90% by the fourth year. Approximately half of symptomatic menstrual irregularity is due to neuroendocrine immaturity, and half is associated with increased androgen levels. The former is manifest as aluteal or short/deficient luteal phase cycles and usually resolves spontaneously. The latter seems related to polycystic ovary syndrome because adolescent androgen levels are associated with adult androgens and ovulatory dysfunction, but data are sparse. Obesity causes hyperandrogenemia and, via unclear mechanisms, seems to suppress LH; it may mimic polycystic ovary syndrome. The role of pubertal insulin resistance in physiological adolescent anovulation is unclear. High-sensitivity gonadotropin and steroid assays, the latter by specialty laboratories, are necessary for accurate diagnosis of pubertal disorders. Polycystic ovaries are a normal ultrasonographic finding in young women and are associated with nearly 2-fold increased anti-Müllerian hormone levels. Oral contraceptives are generally the first-line treatment for ongoing menstrual dysfunction, and the effects of treatment are similar among preparations. Conclusions: Menstrual cycle duration persistently outside 21–45 days in adolescents is unusual, and persistence ≥ 1 year suggests that disordered hypothalamic-pituitary-gonadal function be considered. Research is needed on the mechanisms and prognosis of adolescent anovulation. PMID:23913942

  12. Calcium and magnesium content of the uterine fluid and blood serum during the estrous cycle and pre-pubertal phase in water buffaloes.

    PubMed

    Alavi Shoushtari, Sayed Mortaza; Asri Rezaie, Siamak; Khaki, Amir; Belbasi, Abulfazle; Tahmasebian, Hamid

    2014-01-01

    To investigate uterine fluid and serum calcium (Ca) and Magnesium (Mg) variations during the estrus cycle in water buffaloes, 71 genital tracts and blood samples were collected from the abattoir in Urmia. The phase of the estrous cycle was determined by examining ovarian structures. 18 animals were pro-estrous, 15 estrous, 16 met-estrous and 22 diestrous. The uterine fluid was collected by gentle scraping of the uterine mucosa with a curette. Blood serum and uterine fluid samples of 71 pre-pubertal buffalo calves were also collected and treated in similar manners. The mean ± SEM total serum and uterine fluid Ca in cyclic buffaloes were 8.68 ± 0.28 mg dL(-1) and 8.10 ± 0.2 mg dL(-1) vs. 6.76 ± 0.65 mg dL(-1) and 7.90 ± 0.15 mg dL(-1) in pre-pubertal calves, respectively. Blood serum Mg was not different in cyclic and pre-pubertal animals but the uterine fluid Mg in cyclic cows was higher than those in pre-pubertal calves. Serum Ca in pro-estrus and estrus were higher than those in other stages and also higher than those in the uterine fluid. The lowest Mg content of serum was recorded in diestrus, while in the uterine fluid it was observed in estrus. In all stages of estrous cycle except for estrus the uterine fluid Mg content was significantly higher than those of the serum. These results suggested that during the estrous cycle in the buffalo cows, Ca was passively secreted in uterine lumen and mostly dependent on blood serum Ca concentrations but Mg was secreted independently. The values (except for serum total Mg) also increased after puberty.

  13. Postradiation atrophy of mature bone

    SciTech Connect

    Ergun, H.; Howland, W.J.

    1980-01-01

    The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographic evidence of atrophy, localized osteopenia, is late in appearing. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.

  14. Maturation of the MOUTh Intervention

    PubMed Central

    Jablonski-Jaudon, Rita A.; Kolanowski, Ann M.; Winstead, Vicki; Jones-Townsend, Corteza; Azuero, Andres

    2016-01-01

    The purpose of the current article is to describe a personalized practice originally conceived as a way to prevent and minimize care-resistant behavior to provide mouth care to older adult with dementia. The original intervention, Managing Oral Hygiene Using Threat Reduction Strategies (MOUTh), matured during the clinical trial study into a relationship-centered intervention with emphasis on developing strategies that support residents behavioral health and staff involved in care. Relationships that were initially pragmatic (i.e., focused on the task of completing mouth care) developed into more personal and responsive relationships that involved deeper engagement between mouth care providers and nursing home (NH) residents. Mouth care was accomplished and completed in a manner enjoyable to NH residents and mouth care providers. The MOUTh intervention may also concurrently affirm the dignity and personhood of the care recipient because of its emphasis on connecting with older adults. PMID:26934969

  15. OUTSHORE Maturity Model: Assistance for Software Offshore Outsourcing Decisions

    NASA Astrophysics Data System (ADS)

    Mäkiö, Juho; Betz, Stafanie; Oberweis, Andreas

    Offshore outsourcing software development (OOSD) is increasingly being used by the Software Industry. OOSD is a specific variant of Geographically Distributed Software Developmentdistributed software development (GDSD). Compared to the traditional mode of software development (i.e., in-house) GDSD is more edgy and puts at risk the attainment of the expected results. Although the failure of an offshore outsourcing software project may be caused by a variety of factors, one major complication is geographical distance. Consequently we argue that risk avoidance in outshore software development should be undertaken well in advance of the development launch. This could be done by testing the offshore outsourcing relevance of each software project and then the offshore outsourcing company involved. With this in mind we have developed the OUTSHORE Maturity Modeloutshore maturity model - OMM.

  16. Technology Development Roadmaps - a Systematic Approach to Maturing Needed Technologies

    SciTech Connect

    John W. Colllins; Layne Pincock

    2010-07-01

    Abstract. Planning and decision making represent important challenges for all projects. This paper presents the steps needed to assess technical readiness and determine the path forward to mature the technologies required for the Next Generation Nuclear Plant. A Technology Readiness Assessment is used to evaluate the required systems, subsystems, and components (SSC) comprising the desired plant architecture and assess the SSCs against established Technology Readiness Levels (TRLs). A validated TRL baseline is then established for the proposed physical design. Technology Development Roadmaps are generated to define the path forward and focus project research and development and engineering tasks on advancing the technologies to increasing levels of maturity. Tasks include modeling, testing, bench-scale demonstrations, pilot-scale demonstrations, and fully integrated prototype demonstrations. The roadmaps identify precise project objectives and requirements; create a consensus vision of project needs; provide a structured, defensible, decision-based project plan; and, minimize project costs and schedules.

  17. Hypothalamic-pituitary-gonadal axis function in pubertal male and female siblings with glucocorticoid-treated nonsalt-wasting 3 beta-hydroxysteroid dehydrogenase deficiency congenital adrenal hyperplasia.

    PubMed

    Chang, Y T; Kulin, H E; Garibaldi, L; Suriano, M J; Bracki, K; Pang, S

    1993-11-01

    We report pubertal maturation and dynamic studies of gonadotropin and gonadal hormone secretion in long term glucocorticoid-treated siblings with nonsalt-wasting classic adrenal and gonadal 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) deficiency. The 18-yr-old female siblings spontaneously developed thelarche and menarche at 10 and 12 yr, respectively, and manifested irregular menses, hirsutism, and polycystic ovaries at 17 yr. The 16-yr-old male sibling spontaneously developed secondary sex characteristics at age 11 yr and exhibited Tanner IV-V pubic hair, a 6.5 x 3.0-cm surgically repaired penis, and enlarged nonnodular testes. Overnight (2200-0700 h) plasma gonadotropin (every 20 min) and gonadal steroid levels (every 2 h) under ACTH adrenal suppression revealed the following. In the male sibling, there were overall normal Tanner V male LH (3-21 mIU/mL) and FSH (1.2-13 mIU/mL) levels, normal peak frequency and amplitude of LH (70 +/- 62 min and 15 +/- 3 mIU/mL, respectively) and FSH (65 +/- 28 min and 13 +/- 3 mIU/mL), and low normal Tanner V testosterone (T) levels (11.4-17.9 nmol/L). In the female sibling, there were normal follicular phase range LH (10-28 mIU/mL) and FSH (5.1-17.2 mIU/mL) levels, normal peak frequency and amplitude of LH (96 +/- 17 min and 22 +/- 4.5 mIU/mL, respectively) and FSH (62 +/- 27 min, 13 +/- 4 mIU/mL), and early follicular phase estradiol (E2) levels (100-170 pmol/L). The LH-releasing hormone-stimulated LH response was in the normal adult range in the male and normal for the early follicular phase in the female. In contrast, ACTH and adrenal delta 5-steroid responses to CRH administration were elevated in each sibling. Gonadal suppression via Norlutin administration (30 mg/day for 3 days) after prolonged adrenal suppression by dexamethasone resulted in suppression of dehydroepiandrosterone (DHEA) and E2 in the female and DHEA and T in the male. Gonadal stimulation via hCG administration (5000 IU/day for 3 days, im) during

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

    PubMed Central

    2012-01-01

    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. PMID:23110668

  19. Effects of exposure of pre-pubertal boars to di(2-ethylhexyl) phthalate on their frozen-thawed sperm viability post-puberty.

    PubMed

    Spjuth, L; Saravia, F; Johannisson, A; Lundeheim, N; Rodríguez-Martínez, H

    2006-10-01

    Late effects of pre-pubertal oral exposure to di(2-ethylhexyl) phthalate (DEHP), a plastic softener used in, for example, polyvinyl chloride-products, on semen quality in young boars have not been clear-cut. The aim of this study was to determine whether stress imposed on spermatozoa would reveal such effects. Semen was collected from post-pubertal boars (8-9 months of age), which had been exposed to 300 mg kg(-1) body weight of DEHP per os three times a week from 3 to 7 weeks of age and from control siblings given placebo (water). The semen was cryopreserved and examined for plasma membrane integrity post-thaw using the short hypo-osmotic swelling test and flow cytometry (propidium iodide /SYBR-14). Sperm motility was assessed by computer-assisted sperm analysis. No significant difference in plasma membrane integrity could be found between the groups. The DEHP-exposed group had a significantly lower percentage of linearly motile spermatozoa at 30 min (P < 0.05) and 120 min (P < 0.001) after thawing, and a larger amplitude of lateral displacement of the head 120 min after thawing (P < 0.05), compared with controls. In summary, spermatozoa from boars pre-pubertally exposed to low doses of DEHP, showed kinematic deviations post-thaw that could be related to DEHP exposure. PMID:16961572

  20. Induction of immunocastration in pre-pubertal boars immunized with recombinant gonadotropin-releasing hormone conjugated with Salmonella Typhimurium flagellin fljB.

    PubMed

    Park, Woo-Jung; Park, Byung-Joo; Song, Young-Jo; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Lee, Sang-Won; Jang, Young-Gyu; Kim, Hyoung-Moon; Han, Jang-Hyuck; Jung, Cheong-Hwan; Choi, In-Soo

    2015-05-01

    Immunocastration is an alternative method used to replace surgical castration commonly performed in swine farms. In boars, the main effects of immunocastration are reduction of gonadotropin-releasing hormone (GnRH) and the resulting inhibition of testicular function. The aim of this study was to evaluate immunocastration efficacy in pre-pubertal boars vaccinated with a recombinant GnRH protein conjugated with Salmonella Typhimurium flagellin fljB (STF2). A total of 35 boars were assigned to three groups: the untreated group (n = 5), the surgically castrated group (n = 5), and the immunocastrated group (n = 25). Pigs in the immunocastration group were immunized with the GnRH-STF2 vaccine at pre-pubertal ages 4 and 8 weeks. All experimental pigs were kept for 26 weeks before slaughter. Anti-GnRH antibody levels of immunocastrated pigs were significantly higher than those of untreated pigs (P < 0.001). In contrast, testosterone levels of immunocastrated pigs were significantly lower than those of untreated pigs (P < 0.001). Statistical significances were not found in the body weights and backfat thicknesses of untreated vs. immunocastrated pigs. Weights of the testes and epididymides of immunocastrated pigs were significantly lower than those of untreated pigs (P < 0.001). Testicular tissues of immunocastrated pigs were severely suppressed compared with those of untreated pigs. In conclusion, immunization with the STF2-GnRH vaccine effectively induced immunocastration in pre-pubertal boars. PMID:26164876

  1. In utero and peripubertal exposure to phthalates and BPA in relation to female sexual maturation

    PubMed Central

    Watkins, Deborah J.; Téllez-Rojo, Martha Maria; Ferguson, Kelly K.; Lee, Joyce M.; Solano-Gonzalez, Maritsa; Blank-Goldenberg, Clara; Peterson, Karen E.; Meeker, John D.

    2014-01-01

    The age of pubertal onset for girls has declined over past decades. Research suggests that endocrine disrupting chemicals (EDCs) may play a role but exposure at multiple stages of development has not been considered. We examined in utero and peripubertal exposure to bisphenol-A (BPA) and phthalates in relation to serum hormones and sexual maturation among females in a Mexico City birth cohort. We measured phthalate metabolite and BPA concentrations in urine collected from mothers during their third trimester (n=116) and from their female children at ages 8–13 years (n=129). Among girls, we measured concurrent serum hormone concentrations, Tanner stages for breast and pubic hair development, and collected information on menarche onset. We used linear and logistic regression to model associations between in utero and peripubertal measures of exposure with hormones and sexual maturation, respectively, controlling for covariates. An interquartile range (IQR) increase in in utero urinary mono-2-ethylhexyl phthalate (MEHP) was positively associated with 29% (95% CI:9.2–52.6%) higher dehydroepiandrosterone sulfate (DHEA-S), an early indicator of adrenarche, and 5.3 (95% CI:1.13–24.9) times higher odds of a Tanner stage >1 for pubic hair development. Similar relationships were observed with other in utero but not peripubertal di-2-ethylhexyl phthalate (DEHP) metabolites. IQR increases in in utero monobenzyl phthalate (MBzP) and monoethyl phthalate (MEP) were associated with 29% and 25% higher serum testosterone concentrations (95% CIs:4.3–59.3; 2.1–54.1), respectively. In addition, we observed suggestive associations between in utero and peripubertal MEP concentrations and increased odds of having undergone menarche, and between peripubertal MnBP concentrations and increased odds of having a Tanner stage >1 for both breast and pubic hair development. BPA was not associated with in utero or peripubertal serum hormones or sexual maturation. Our findings suggest in

  2. Retrovirus maturation-an extraordinary structural transformation.

    PubMed

    Mattei, Simone; Schur, Florian Km; Briggs, John Ag

    2016-06-01

    Retroviruses such as HIV-1 assemble and bud from infected cells in an immature, non-infectious form. Subsequently, a series of proteolytic cleavages catalysed by the viral protease leads to a spectacular structural rearrangement of the viral particle into a mature form that is competent to fuse with and infect a new cell. Maturation involves changes in the structures of protein domains, in the interactions between protein domains, and in the architecture of the viral components that are assembled by the proteins. Tight control of proteolytic cleavages at different sites is required for successful maturation, and the process is a major target of antiretroviral drugs. Here we will describe what is known about the structures of immature and mature retrovirus particles, and about the maturation process by which one transitions into the other. Despite a wealth of available data, fundamental questions about retroviral maturation remain unanswered. PMID:27010119

  3. Optimizing IV and V for Mature Organizations

    NASA Technical Reports Server (NTRS)

    Fuhman, Christopher

    2003-01-01

    NASA is intending for its future software development agencies to have at least a Level 3 rating in the Carnegie Mellon University Capability Maturity Model (CMM). The CMM has built-in Verification and Validation (V&V) processes that support higher software quality. Independent Verification and Validation (IV&V) of software developed by mature agencies can be therefore more effective than for software developed by less mature organizations. How is Independent V&V different with respect to the maturity of an organization? Knowing a priori the maturity of an organization's processes, how can IV&V planners better identify areas of need choose IV&V activities, etc? The objective of this research is to provide a complementary set of guidelines and criteria to assist the planning of IV&V activities on a project using a priori knowledge of the measurable levels of maturity of the organization developing the software.

  4. Effects of Nitric oxide synthase blockade on the acute response of the reproductive axis to ethanol in pubertal male rats.

    PubMed

    Emanuele, M A; LaPaglia, N; Steiner, J; Kirsteins, L; Emanuele, N V

    1999-05-01

    The effects of ethanol (EtOH) and nitric oxide (NO) are well known in the adult male rat reproductive axis. In the present study, we investigate the effects of EtOH, NO, and their interaction on key genes and reproductive hormone levels in mid- (45-day) and late pubertal (55-day) male rats. Using three different NO synthase blockers--N'omega-nitro-L-arginine methyl ester (L-NAME), N'omega-nitro-L-arginine (L-NA), and 7-nitroindazole--we show that it is possible to block, in part, some of the disruptive effects of EtOH. L-NAME totally prevented the EtOH-induced fall in serum testosterone in both 45- and 55-day-old rats (p < 0.05 and p < 0.001, respectively). On the other hand, the D-NAME, an inactive isomer of L-NAME, did not protect testosterone from suppression caused by EtOH. Similarly, L-NA and 7-nitroindazole prevented the suppression of testosterone caused by EtOH in 55-day-old animals (p < 0.001 L-NA and p < 0.05 for 7-nitroindazole), but not in the 45-day-old rats. Serum luteinizing hormone (LH) was significantly reduced by EtOH in all the studies in both age groups. L-NAME (but not D-NAME) and L-NA prevented this inhibition in 55-day-old animals (p < 0.001 for L-NAME and p < 0.01 for L-NA). However, only L-NA was able to prevent the effects of EtOH on LH in the 45-day-old rats. 7-Nitroindazole was unable to prevent the decrease in LH in either age group. Despite changes in the other reproductive hormones, there were no consistent changes in hypothalamic concentrations of either LH releasing hormone (LHRH) or its precursor, pro-LHRH. No treatment caused any change in steady-state levels of beta-LH mRNA. There were no consistent changes in pro-LHRH mRNA; but, interestingly, in 45-day-old rats, L-NA given with or without EtOH lead to a significant fall in LHRH gene expression. Our findings indicate that the acute suppressive effects of EtOH on the hypothalamic-pituitary-gonadal axis of the pubertal male rat can be at least partially prevented by NO synthase

  5. Comparison of Conservative and Surgical Therapy Concepts for Synechia of the Labia in Pre-Pubertal Girls

    PubMed Central

    Bussen, S.; Eckert, A.; Schmidt, U.; Sütterlin, M.

    2016-01-01

    Introduction: The aim of this study was to evaluate the primary and secondary therapeutic successes of different therapy schemes for the treatment of synechia of the labia in pre-pubertal girls. Materials and Methods: The treatment courses of 47 pre-pubertal girls who were treated between February 2007 and February 2013 in the special outpatient clinic for paediatric gynaecology of a department for gynaecology at a German university hospital and for whom information on the course of the disease was available for at least the six months following end of the treatment. 23 of these children were treated with a topical estriol therapy (treatment group A). For 24 of the girls a manual separation of the adhering labia minora was undertaken (treatment group B). Statistical evaluation was performed using the χ2 test, Fischerʼs exact test and the Mann-Whitney U test. Results: For 18 of the 23 (80 %) girls in treatment group A topical estriol therapy alone led to a resolution of the synechia. Five of these 23 children (20 %) required a secondary manual separation. All girls for whom treatment was not successful were under 5 years of age. For all 24 girls (100 %) of treatment group B the primary manual separation was performed with success. The recurrence rates after ≥ 6 months in cases with identical after-care did not differ between the two treatment groups (treatment group A: 34 %, treatment group B: 33 %, χ2 test: p = 0.853). 16 of the 17 recurrences occurred ≥ 3 months after the end of the therapy. Conclusion: Our results show that for children < 5 years of age a 4-week topical therapy with estriol is a promising therapy option for synechia of the labia that is less of a burden for the family situation. Especially for girls ≥ 5 years of age, primary therapy fails in up to 20 % of the cases. Primary manual separation represents a more effective therapeutic option. Irrespective of the treatment applied, a recurrence after ≥ 3 must be

  6. Influence of pre- and post-pubertal grazing regimes on adult testicular morphology in extensively reared corriedale rams.

    PubMed

    Bielli, A; Gastel, M T; Pedrana, G; Moraña, A; Castrillejo, A; Lundeheim, N; Forsberg, M; Rodriguez-Martinez, H

    2000-02-28

    The aim of the present study was to determine whether pre- and post-pubertal young rams on different grazing regimes, resulting in differences in live weight (LW), would show corresponding differences in testicular growth or testicular morphometry that could influence the reproductive traits of these rams upon reaching adulthood. Forty-one spring-born Corriedale rams were reared on either native pasture (low feeding level, Group L, n=22) or improved pasture (higher feeding level, Group H, n=19) from 1 to 7 months of age. Thereafter, half the animals in the native-pasture group were placed on improved pasture and vice versa, thus creating an additional four differential-grazing treatment groups (Groups LL, n=11; LH, n=11; HL, n=10; and HH, n=9). Animals were managed in this way until 18 months of age. Half the animals from each group were then castrated and their testes were subjected to morphometric analysis. The remaining animals (Groups LL, n=6; LH, n=6; HL, n=5; and HH, n=4) were managed together until 30 months of age (from 18 to 27 months on native pastures and from 27 to 30 months of age on improved pastures, at a stocking rate of two to three rams per hectare), whereupon they were also castrated for testicular morphometry. LW and scrotal circumference (SC) were recorded every 60 days. The stereological analysis of testicular parenchyma included counts of elongated spermatids and Sertoli cells. Differences (P<0.001) in LW were observed between feeding levels, even at 30 months of age. Differences (P<0.001) in SC existing at the end of the differential treatment (18 months of age) disappeared (n.s.) soon after. Most differences (P<0.05) in testicular morphometry existing at the end of the differential treatments were no longer significant 1 year later. It is concluded that changes in grazing management during pre- and post-pubertal periods can induce short-lived differences in testicular post-natal growth in Corriedale rams but do not influence testicular

  7. The effect of a complex training and detraining programme on selected strength and power variables in early pubertal boys.

    PubMed

    Ingle, Lee; Sleap, Mike; Tolfrey, Keith

    2006-09-01

    Complex training, a combination of resistance training and plyometrics is growing in popularity, despite limited support for its efficacy. In pre- and early pubertal children, the study of complex training has been limited, and to our knowledge an examination of its effect on anaerobic performance characteristics of the upper and lower body has not been undertaken. Furthermore, the effect of detraining after complex training requires clarification. The physical characteristics (mean+/-s) of the 54 male participants in the present study were as follows: age 12.3 +/- 0.3 years, height 1.57 +/- 0.07 m, body mass 50.3 +/- 11.0 kg. Participants were randomly assigned to an experimental (n = 33) or control group (n = 21). The training, which was performed three times a week for 12 weeks, included a combination of dynamic constant external resistance and plyometrics. After training, participants completed 12 weeks of detraining. At baseline, after training and after detraining, peak and mean anaerobic power, dynamic strength and athletic performance were assessed. Twenty-six participants completed the training and none reported any training-related injury. Complex training was associated with small increases (< or =5.5%) in peak and mean power during training, followed by decreases of a similar magnitude (< or = -5.9%) during detraining (P < 0.05). No changes or minor, progressive increases (< or =1.5%) were evident in the control group (P > 0.05). In the experimental group, dynamic strength was increased by 24.3 - 71.4% (dependent on muscle group; P < 0.01), whereas growth-related changes in the control group varied from 0 to 4.4% (P > 0.05). For 40-m sprint running, basketball chest pass and vertical jump test performance, the experimental group saw a small improvement (< or =4.0%) after training followed by a decline (< or = -4.4%) towards baseline during detraining (P < 0.05), whereas the control group experienced no change (P > 0.05). In conclusion, in pre- and early

  8. Saturation of subcutaneous adipose tissue expansion and accumulation of ectopic fat associated with metabolic dysfunction during late and post-pubertal growth

    PubMed Central

    Gyllenhammer, Lauren E.; Alderete, Tanya L.; Toledo-Corral, Claudia M.; Weigensberg, Marc; Goran, Michael I.

    2015-01-01

    Background/Objective Puberty is a period defined by large changes in adipose tissue accumulation and distribution, however longitudinal patterns of ectopic fat development have not been shown. We have previously shown significant declines in beta-cell function (BCF) across puberty and hypothesize that accumulation of ectopic fat deposition, particularly hepatic fat, will predict this fall. Subject/Methods We conducted a longitudinal study and examined 2-year change in abdominal fat distribution and type 2 diabetes risk markers in 76 Hispanic children and young adults (16.1 ±0.5 years, 66% obese, 52% male, 51% post-pubertal). Subcutaneous abdominal adipose tissue (SAAT), visceral adipose tissue (VAT), hepatic fat fraction (HFF) and pancreatic fat fraction (PFF) were measured by 3-Tesla MRI, and markers of type 2 diabetes risk were collected at fasting and during an oral glucose tolerance test (OGTT). Results Baseline pubertal status significantly moderated 2-year change in ectopic fat deposition, such that VAT, HFF and PFF increased in individuals during late and post-pubertal growth whereas children earlier in their pubertal development decreased ectopic accumulation and had less VAT accumulation (VAT: pTanner*time =0.044, 0.31±0.08L vs. 0.03±0.10L; HFF: pTanner*time=0.007, 1.34±0.87% vs. −2.61±1.11%; PFF: pTanner*time<0.001, 1.61±0.39% vs. −0.96±0.50%). Independent of pubertal status, two-year increase in HFF and VAT significantly associated with a decline in BCF (β=−1.04, p=0.038; β=−1.81, p=0.020) and metabolic function, while accumulation of SAAT significantly associated with BCF (β=1.36, p=0.012) and metabolic improvement. HFF accumulation was the only depot to significantly predict clinical markers of type 2 diabetes risk, fasting glucose and HbA1c, and circulating free fatty acid levels (β=1.00, p=0.034; β=1.00, p=0.015; β=01.01, p=0.024). Conclusions The accumulation of SAAT defends against type 2 diabetes risk and potentially ectopic

  9. Prepubertal Exposure to Arsenic(III) Suppresses Circulating Insulin-like Growth Factor-1 (IGF-1) Delaying Sexual Maturation in Female Rats

    PubMed Central

    Reilly, Michael P.; Saca, James C.; Hamilton, Alina; Solano, Rene F.; Rivera, Jesse R.; Whitehouse-Innis, Wendy; Parsons, Jason G.; Dearth, Robert K.

    2013-01-01

    Arsenic (As) is a prevalent environmental toxin; readily accessible for human consumption and has been identified as an endocrine disruptor. However, it is not known what impact As has on female sexual maturation. Therefore, in the present study, we investigated the effects of prepubertal exposure on mammary gland development and pubertal onset in female rats. Results showed that prepubertal exposure to 10mg/kg of arsenite (As(III)) delayed vaginal opening (VO) and prepubertal mammary gland maturation. We determined that As accumulates in the liver, disrupts hepatocyte function and suppresses serum levels of the puberty related hormone insulin-like growth factor 1 (IGF-1) in prepubertal animals. Overall, this is the first study to show that prepubertal exposure to As(III) acts peripherally to suppresses circulating levels of IGF-1 resulting in delayed sexual maturation. Furthermore, this study identifies a critical window of increased susceptibility to As(III) that may have a lasting impact on female reproductive function. PMID:24090629

  10. A longitudinal examination of the influence of maturation on physical self-perceptions and the relationship with physical activity in early adolescent girls.

    PubMed

    Knowles, Ann-Marie; Niven, Ailsa G; Fawkner, Samantha G; Henretty, Joan M

    2009-06-01

    This longitudinal study investigated the influence of maturation on physical self-perceptions and the relationship with physical activity in early adolescent girls (N=150; mean age=12.79+/-0.31). Physical characteristics were measured and participants completed the Physical Activity Questionnaire for Children, the Children and Youth Physical Self-Perception Profile and the Pubertal Development Scale on two occasions 12 months apart. The results demonstrated a decrease in overall physical activity levels over 12 months which was not influenced by maturational status or physical characteristics. Additional analysis indicated that physical self-perceptions partially accounted for the explained variance in physical activity change, with physical condition being an important individual predictor of physical activity. Further analysis indicated that body mass was an important individual predictor of changes in perceptions of body attractiveness and physical self-worth. At this age maturation has a limited influence on the physical activity behaviours of early adolescent girls and although the variance in physical activity was partly accounted for by physical self-perceptions, this was a relatively small contribution and other factors related to this drop in physical activity need to be considered longitudinally. PMID:18692232

  11. Advanced vaginal opening and precocious activation of the reproductive axis by KiSS-1 peptide, the endogenous ligand of GPR54

    PubMed Central

    Navarro, VM; Fernández-Fernández, R; Castellano, JM; Roa, J; Mayen, A; Barreiro, ML; Gaytan, F; Aguilar, E; Pinilla, L; Dieguez, C; Tena-Sempere, M

    2004-01-01

    The awakening of the gonadotrophic axis at puberty is the end-point of a complex cascade of sex developmental events that leads to the attainment of reproductive capacity. Recently, loss-of-function mutations of the gene encoding GPR54, the putative receptor for the KiSS-1-derived peptide metastin, have been linked to hypogonadotrophic hypogonadism, both in rodents and humans. However, the actual role of the KiSS-1/GPR54 system in the timing of puberty onset remains unexplored. We report herein that chronic central administration of KiSS-1 peptide to immature female rats induced the precocious activation of the gonadotrophic axis, as estimated by advanced vaginal opening, elevated uterus weight, and increased serum levels of luteinizing hormone (LH) and oestrogen. The central effect of KiSS-1 upon LH release appeared to be mediated via the hypothalamic LH-releasing hormone. In contrast, despite the well-documented permissive role of body fat stores and the adipocyte-derived hormone leptin in puberty maturation, acute activation of the gonadotrophic axis by KiSS-1 was persistently observed in pubertal animals under food deprivation, after central immunoneutralization of leptin, and in a model of leptin resistance. Overall, the present results, together with our recent data on maximum expression of KiSS-1 and GPR54 genes in the hypothalamus at puberty, provide novel evidence for a role of the KiSS-1 system as a downstream element in the hypothalamic network triggering the onset of puberty. PMID:15486019

  12. Advanced vaginal opening and precocious activation of the reproductive axis by KiSS-1 peptide, the endogenous ligand of GPR54.

    PubMed

    Navarro, V M; Fernández-Fernández, R; Castellano, J M; Roa, J; Mayen, A; Barreiro, M L; Gaytan, F; Aguilar, E; Pinilla, L; Dieguez, C; Tena-Sempere, M

    2004-12-01

    The awakening of the gonadotrophic axis at puberty is the end-point of a complex cascade of sex developmental events that leads to the attainment of reproductive capacity. Recently, loss-of-function mutations of the gene encoding GPR54, the putative receptor for the KiSS-1-derived peptide metastin, have been linked to hypogonadotrophic hypogonadism, both in rodents and humans. However, the actual role of the KiSS-1/GPR54 system in the timing of puberty onset remains unexplored. We report herein that chronic central administration of KiSS-1 peptide to immature female rats induced the precocious activation of the gonadotrophic axis, as estimated by advanced vaginal opening, elevated uterus weight, and increased serum levels of luteinizing hormone (LH) and oestrogen. The central effect of KiSS-1 upon LH release appeared to be mediated via the hypothalamic LH-releasing hormone. In contrast, despite the well-documented permissive role of body fat stores and the adipocyte-derived hormone leptin in puberty maturation, acute activation of the gonadotrophic axis by KiSS-1 was persistently observed in pubertal animals under food deprivation, after central immunoneutralization of leptin, and in a model of leptin resistance. Overall, the present results, together with our recent data on maximum expression of KiSS-1 and GPR54 genes in the hypothalamus at puberty, provide novel evidence for a role of the KiSS-1 system as a downstream element in the hypothalamic network triggering the onset of puberty. PMID:15486019

  13. Postradiation atrophy of mature bone

    SciTech Connect

    Erguen, H.; Howland, W.J.

    1980-01-01

    The growing number of oncological patients subjected to radiotherapy require the diagnostic radiologist to be aware of expected bone changes following irradiation and the differentiation of this entity from metastasis. The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographic evidence of atrophy, localized osteopenia, is late in appearing, mainly because of the relative insensitivity of radiographs in detecting demineralization. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. In vivo midrodensitometric analysis and radionuclide bone and bone marrow scans can reveal early changes following irradiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.

  14. Postradiation atrophy of mature bone

    SciTech Connect

    Ergun, H.; Howland, W.J.

    1980-01-01

    The growing number of oncological patients subjected to radiotherapy require the diagnostic radiologist to be aware of expected bone changes following irradiation and the differentiation of this entity from metastasis. The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographic evidence of atrophy, localized osteopenia, is late in appearing, mainly because of the relative insensitivity of radiographs in detecing demineralization. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. In vivo midrodensitometric analysis and radionuclide bone and bone marrow scans can reveal early changes following irradiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.

  15. Smart Grid Interoperability Maturity Model

    SciTech Connect

    Widergren, Steven E.; Levinson, Alex; Mater, J.; Drummond, R.

    2010-04-28

    The integration of automation associated with electricity resources (including transmission and distribution automation and demand-side resources operated by end-users) is key to supporting greater efficiencies and incorporating variable renewable resources and electric vehicles into the power system. The integration problems faced by this community are analogous to those faced in the health industry, emergency services, and other complex communities with many stakeholders. To highlight this issue and encourage communication and the development of a smart grid interoperability community, the GridWise Architecture Council (GWAC) created an Interoperability Context-Setting Framework. This "conceptual model" has been helpful to explain the importance of organizational alignment in addition to technical and informational interface specifications for "smart grid" devices and systems. As a next step to building a community sensitive to interoperability, the GWAC is investigating an interoperability maturity model (IMM) based on work done by others to address similar circumstances. The objective is to create a tool or set of tools that encourages a culture of interoperability in this emerging community. The tools would measure status and progress, analyze gaps, and prioritize efforts to improve the situation.

  16. Motivational maturity and helping behavior.

    PubMed

    Haymes, M; Green, L

    1977-12-01

    This study was undertaken to examine the independent influences of conative development (the Maslow needs hierarchy) upon behavioral aspects of prosocial orientations. It provides a behavioral demonstration of conative effects in a helping paradigm, among college-age men. A comparison of the conative data across the ages of 15-22 provided a cross-sectional view of conative development itself. Conative maturity was found to be predictive of greater helping among college-age men. Situational demands were demonstrated which tended to mask, but not override, these predispositional influences on helping. The cross-sectional data on conative development point to probable movement to early esteem concerns among high school men who have reached the conative level of love and belonging. On the other hand, the stability across the years of 15-22 of proportion of safety concerns suggests fixation of such concerns in those exhibiting them in high school. Results are discussed in terms of conative growth for development of prosocial orientations.

  17. Temporal Relationship Between Insulin Sensitivity and the Pubertal Decline in Physical Activity in Peripubertal Hispanic and African American Females

    PubMed Central

    Spruijt-Metz, Donna; Belcher, Britni R.; Hsu, Ya-Wen; McClain, Arianna D.; Chou, Chih-Ping; Nguyen-Rodriguez, Selena; Weigensberg, Marc J.; Goran, Michael I.

    2013-01-01

    OBJECTIVE Little attention has been paid to possible intrinsic biological mechanisms for the decline in physical activity that occurs during puberty. This longitudinal observational study examined the association between baseline insulin sensitivity (SI) and declines in physical activity and increases in sedentary behavior in peripubertal minority females over a year. RESEARCH DESIGN AND METHODS Participants were Hispanic and African American girls (n = 55; 76% Hispanic; mean age 9.4 years; 36% obese). SI and other insulin indices were measured at baseline using the frequently sampled intravenous glucose tolerance test. Physical activity was measured on a quarterly basis by accelerometry and self-report. RESULTS Physical activity declined by 25% and time spent in sedentary behaviors increased by ∼13% over 1 year. Lower baseline SI predicted the decline in physical activity measured by accelerometry, whereas higher baseline acute insulin response to glucose predicted the decline in physical activity measured by self-report. Time spent in sedentary behavior increased by ~13% over 1 year, and this was predicted by lower baseline SI. All models controlled for adiposity, age, pubertal stage, and ethnicity. CONCLUSIONS When evaluated using a longitudinal design with strong outcome measures, this study suggests that lower baseline SI predicts a greater decline in physical activity in peripubertal minority females. PMID:23846812

  18. Endocrine and testicular changes associated with season, artificial photoperiod, and the peri-pubertal period in stallions.

    PubMed

    Clay, C M; Clay, J N

    1992-04-01

    The seasonal reproductive cycle of stallions is characterized by an annual regression and recrudescence in testicular function and concentrations of LH, FSH, and testosterone in serum. Maximum reproductive capacity occurs during the increasing day lengths of spring and summer. The annual cycle in LH secretion may reflect a seasonally associated and photosensitive reduction and replenishment in pituitary content of LH. Similar to other seasonal breeders, it appears that stallions may possess an endogenous circannual rhythm in reproductive function that is subject to manipulation by altering the light:dark ratio, i.e., photoperiod. The application of a long-day photoperiod (16 hours light:8 hours dark) in December, following 20 weeks of short days (8 hours light:16 hours dark), was effective in hastening the seasonal sexual recrudescence of stallions but was not effective in prolonging the interval of heightened reproductive capacity. The infantile period in colts lasts approximately 32 weeks and is characterized by low gonadotropin concentrations and little gonadal activity. The start of the pre-pubertal period is marked by changes in the hypothalamic-pituitary axis which result in increased amounts of LH and FSH secretion between 32 and 40 weeks of age. Testosterone concentrations in serum exhibit a dramatic increase at 75 to 80 weeks of age, with puberty (defined as the age when the first ejaculate was obtained containing a minimum of 50 x 10(6) sperm with greater than or equal to 10% progressive motility) occurring at 83 weeks of age.

  19. Hormonal profile in pubertal females with chronic renal failure: before and under haemodialysis and after renal transplantation.

    PubMed

    Ferraris, J R; Domene, H M; Escobar, M E; Caletti, M G; Ramirez, J A; Rivarola, M A

    1987-07-01

    The effects of chronic renal failure on the hypothalamic-pituitary-ovarian axis in 25 girls, aged 9.1 to 20.9 years (mean 13.8) were studied. Twelve patients on conservative treatment (group A) had serum creatinine values between 176.8 and 1502.8 mumol/l; 9 patients were on haemodialysis (group B); and 12 patients had received a renal transplant (group C). Tanner stage of breast development was delayed relative to chronological age in 5 out of 18 patients. Serum oestradiol was normal or low when related to pubertal stages in all groups. Serum LH was elevated in group A and B patients, but normal in group C patients. Serum FSH was elevated in 6 out of the 21 patients in group A plus B, and in 2 out of the 12 patients in group C. Serum PRL was elevated in 12/12, 6/8, and 4/11 patients in group A, B, and C respectively. After GnRH administration to 4 patients in group A, 3 showed delayed or absent gonadotropin response; all 4 patients studied in group C showed normal gonadotropin response. The data indicate a decreased E2 secretion, abnormal gonadotropin and PRL levels and a blunted gonadotropin response to GnRH in girls with chronic renal failure. These results seem to indicate an alteration of the hypothalamic-pituitary unit that can be reversed after successful renal transplantation.

  20. A generational study of glyphosate-tolerant soybeans on mouse fetal, postnatal, pubertal and adult testicular development.

    PubMed

    Brake, Denise G; Evenson, Donald P

    2004-01-01

    The health safety of transgenic soybeans (glyphosate-tolerant or Roundup Ready) was studied using the mammalian testis (mouse model) as a sensitive biomonitor of potential toxic effects. Pregnant mice were fed a transgenic soybean or a non-transgenic (conventional) diet through gestation and lactation. After weaning, the young male mice were maintained on the respective diets. At 8, 16, 26, 32, 63 and 87 days after birth, three male mice and an adult reference mouse were killed, the testes surgically removed, and the cell populations measured by flow cytometry. Multi-generational studies were conducted in the same manner. The results showed that the transgenic foodstuffs had no effect on macromolecular synthesis or cell growth and differentiation as evidenced by no differences in the percentages of testicular cell populations (haploid, diploid, and tetraploid) between the transgenic soybean-fed mice and those fed the conventional diet. Additionally, there were no differences in litter sizes and body weights of the two groups. It was concluded that the transgenic soybean diet had no negative effect on fetal, postnatal, pubertal or adult testicular development.

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

    PubMed Central

    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

    2013-01-01

    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, Leibenluft, McClure, and Pine, 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, M age = 10.1 and 13.1 years at timepoints 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 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. PMID:23616547

  2. The long-term effects of the herbicide atrazine on the dopaminergic system following exposure during pubertal development.

    PubMed

    Li, Yanshu; Sun, Yan; Yang, Junwei; Wu, Yanping; Yu, Jia; Li, Baixiang

    2014-03-15

    Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) is used worldwide as a herbicide, and its presence in the environment has resulted in documented human exposure. Atrazine has been shown to cause dopaminergic neurotoxicity. The juvenile period is particularly vulnerable to environmental agents, but only few studies have investigated the long-term effects of atrazine following exposure during the pubertal development. Therefore, we evaluated the effects of a 41-day exposure to atrazine on the dopaminergic system in rats. Sprague-Dawley rats were treated orally with atrazine at 25 or 50mg/kg bw, daily from postnatal day 22 to 62. The content of dopamine (DA) was examined in striatum samples by HPLC-FL, and the mRNA and protein expression of tyrosine hydroxylase (TH), orphan nuclear hormone (Nurr1), dopamine transporter (DAT) and vesicular monoaminetransporter 2 (VMAT2) were examined in samples of the ventral mid-brain by use of fluorescence PCR and Western-blot analysis when the rats reached the age of one year. Exposure of juvenile rats to the high dose of atrazine led to reduced levels of DA and mRNA of Nurr1 in one-year-old animals. This study shows that the long-term adverse effects of atrazine on the dopaminergic system have a special relevance after juvenile exposure.

  3. Association of iron depletion with menstruation and dietary intake indices in pubertal girls: the healthy growth study.

    PubMed

    Moschonis, George; Papandreou, Dimitrios; Mavrogianni, Christina; Giannopoulou, Angeliki; Damianidi, Louisa; Malindretos, Pavlos; Lionis, Christos; Chrousos, George P; Manios, Yannis

    2013-01-01

    The aim of the present study was to investigate the associations of iron depletion (ID) with menstrual blood losses, lifestyle, and dietary habits, in pubertal girls. The study sample comprised 1222 girls aged 9-13 years old. Biochemical, anthropometrical, dietary, clinical, and physical activity data were collected. Out of 274 adolescent girls with menses, 33.5% were found to be iron depleted (defined as serum ferritin < 12 μg/L) compared to 15.9% out of 948 girls without menses. Iron-depleted girls without menses were found to have lower consumption of poultry (P = 0.017) and higher consumption of fruits (P = 0.044) and fast food (P = 0.041) compared to their peers having normal iron status. Multivariate logistic regression analysis showed that girls with menses were 2.57 (95% CI: 1.37, 4.81) times more likely of being iron depleted compared to girls with no menses. Iron depletion was found to be associated with high calcium intake, high consumption of fast foods, and low consumption of poultry and fruits. Menses was the only factor that was found to significantly increase the likelihood of ID in these girls. More future research is probably needed in order to better understand the role of diet and menses in iron depletion.

  4. Comparative proteomic profiling and possible toxicological mechanism of acute injury induced by carbon ion radiation in pubertal mice testes

    NASA Astrophysics Data System (ADS)

    Zhang, Hong

    2016-07-01

    We investigated potential mechanisms of acute injury in pubertal mice testes after exposure to carbon ion radiation (CIR). Serum testosterone was measured following whole-body irradiation with a 2Gy carbon ion beam. Comparative proteomic profiling and Western blotting were applied to identify potential biomarkers and measure protein expression, and terminal dUTP nick end-labeling (TUNEL) was performed to detect apoptotic cells. Immunohistochemistry and immunofluorescence were used to investigate protein localization. Serum testosterone was lowest at 24h after CIR, and 10 differentially expressed proteins were identified at this time point that included eIF4E, an important regulator of initiation that combines with mTOR and 4EBP1 to control protein synthesis via the mTOR signalling pathway during proliferation and apoptosis. Protein expression and localization studies confirmed their association with acute injury following exposure to CIR. These three proteins may be useful molecular markers for detecting abnormal spermatogenesis following exposure to environmental and cosmic radiation

  5. Salinity and photoperiod modulate pubertal development in Atlantic salmon (Salmo salar).

    PubMed

    Melo, Michelle C; Andersson, Eva; Fjelldal, Per Gunnar; Bogerd, Jan; França, Luiz R; Taranger, Geir Lasse; Schulz, Rüdiger W

    2014-03-01

    The Atlantic salmon shows substantial life cycle plasticity, which also applies to the timing of puberty. While it is characterized by the activation of the brain-pituitary-gonad axis, many morphophysiological aspects of puberty and the influence of environmental conditions, such as water salinity, are not well understood in fish. Here, 12-month-old Atlantic salmon coming from an out-of-season smoltification regime in December were exposed to freshwater (FW) or seawater (SW) at 16 °C to stimulate puberty under a 24-h constant light (LL) or 12 h light:12 h darkness (LD) photoperiod. These four treatment groups (FWLL, SWLL, FWLD, and SWLD) were studied from January to March. Next to 11-ketotestosterone (11-KT) plasma levels, the expression of pituitary genes (gnrhr4, fshb, and lhb) and spermatogenesis was quantified. When spermatogonial proliferation started, fshb mRNA levels increased steeply and began to decrease when spermatogonial mitosis approached completion and most germ cells had reached meiotic or post-meiotic stages. Conversely, lhb mRNA levels increased progressively during spermatogenesis. Most males in all treatment groups matured, but exposure to SW resulted in the strongest stimulation of the onset of spermatogenesis and elevation of pituitary gnrhr4 and fshb mRNA levels. Later on, the LD photoperiod accelerated, irrespective of the salinity, the completion of spermatogenesis, associated with higher lhb mRNA and 11-KT plasma levels than in the LL groups. We find that both salinity and photoperiod modulated different aspects of spermatogenesis, and resulted in a differential activation of pituitary and testis functions; SW stimulating the onset and the shorter photoperiod the completion of spermatogenesis.

  6. Decision-Making Style and Vocational Maturity.

    ERIC Educational Resources Information Center

    Phillips, Susan D.; Strohmer, Douglas C.

    1982-01-01

    Examined the relationship between decision-making style, scholastic achievement, and vocational maturity for college students (N=64). Results did not support the hypothesized relationship between rationality and attitudinal and cognitive maturity. Scholastic achievement and lack of dependent decision style were found to be moderately predictive of…

  7. Motivation and Maturity Patterns in Marital Success.

    ERIC Educational Resources Information Center

    McClelland, David C.; And Others

    1978-01-01

    Married couples rated their marital satisfaction and played interpersonal competitive games which revealed the success with which they interacted. Younger husbands who scored more maturely on the Stewart measure of psychosocial maturity belonged to more successful marriages, as did college-educated wives who showed less immaturity and more phallic…

  8. 7 CFR 29.6026 - Maturity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Maturity. 29.6026 Section 29.6026 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6026 Maturity. The degree of ripeness. (See chart.)...

  9. 13 CFR 120.933 - Maturity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Maturity. 120.933 Section 120.933 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) 504 Loans and Debentures § 120.933 Maturity. From time to time, SBA will publish in...

  10. New definitions for cotton fiber maturity ratio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton fiber maturity affects fiber physical, mechanical, and chemical properties, as well as the processability and qualities of yarn and fabrics. New definitions of cotton fiber maturity ratio are introduced. The influences of sampling, sample preparation, measurement method, and correlations am...

  11. The FMI: Dimensions of Follower Maturity

    ERIC Educational Resources Information Center

    Moore, Loren I.

    1976-01-01

    The Follower Maturity Index (FMI) is an instrument derived from leadership theory and based on observations of verbal and nonverbal behavior of followers in task groups. Dimensions of follower maturity--achievement, responsibility, experience, activity, dependence, variety, interests, perspective, position, and awareness--are discussed. For…

  12. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the stage of development which will insure the proper completion of the ripening process. Before a mature apple becomes overripe it will show varying degrees of...

  13. 7 CFR 51.312 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.312 Mature. “Mature” means that the apples have reached the stage of development which will insure the proper completion of the ripening process. Before a mature apple becomes overripe it will show varying degrees of...

  14. Quantifying Semantic Linguistic Maturity in Children

    ERIC Educational Resources Information Center

    Hansson, Kristina; Bååth, Rasmus; Löhndorf, Simone; Sahlén, Birgitta; Sikström, Sverker

    2016-01-01

    We propose a method to quantify "semantic linguistic maturity" (SELMA) based on a high dimensional semantic representation of words created from the co-occurrence of words in a large text corpus. The method was applied to oral narratives from 108 children aged 4;0-12;10. By comparing the SELMA measure with maturity ratings made by human…

  15. Vocational Maturity among Inner-City Youths

    ERIC Educational Resources Information Center

    Maynard, Peter E.; Hansen, James C.

    1970-01-01

    This study investigates the efficacy of the Vocational Development Inventory in measuring the vocational maturity of inner city boys. Intelligence test results were converted to standardized T scores. Mean vocational maturity scores indicate large differences which disappear when intelligence is controlled by analysis of convariance. A variety of…

  16. Career Maturity and College Student Persistence.

    ERIC Educational Resources Information Center

    Perry, Stephen R.; Cabrera, Alberto F.; Vogt, W. Paul

    1999-01-01

    A study examined the role of career maturity in the college persistence of 307 freshmen at a public, residential, four-year college. Results indicate that the My Vocational Situation instrument is reliable and valid, although theoretical formulations should be reexamined. Career maturity was positively associated with several variables important…

  17. 7 CFR 51.1865 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Fresh Tomatoes 1 Definitions § 51.1865 Mature. Mature means that the tomato has reached the stage of development which will insure a proper completion of the ripening process, and that...

  18. 7 CFR 51.1907 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Consumer Standards for Fresh Tomatoes Definitions § 51.1907 Mature. Mature means that the tomato has reached the stage of development which will insure a proper completion of the ripening process....

  19. Canopy temperature and maturity in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat units are a widely used indicator of maturity in cotton. It is generally assumed that it takes approximately 2200°F (1222°C) heat units for a cotton plant on the South High Plains of Texas to mature. This value is based on a typical planting date of May 15 with ample irrigation. As water for c...

  20. 7 CFR 51.1313 - Mature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... stage of maturity which will insure the proper completion of the ripening process. (b) Before a mature... process. Therefore, a statement of firmness should be given in order to indicate the stage of the ripening process. A description of the ground color should also be given. (1) The following terms should be...

  1. 7 CFR 51.1313 - Mature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... stage of maturity which will insure the proper completion of the ripening process. (b) Before a mature... process. Therefore, a statement of firmness should be given in order to indicate the stage of the ripening process. A description of the ground color should also be given. (1) The following terms should be...

  2. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus, Post Office Box 148... § 51.1158 Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as...

  3. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February...

  4. 7 CFR 51.767 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February...

  5. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus, Post Office Box 148... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February...

  6. 7 CFR 51.1158 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus, Post Office Box 148... § 51.1158 Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as...

  7. 7 CFR 51.1823 - Mature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...(a) and 1 CFR part 51. Copies may be obtained from, Florida Department of Citrus, Post Office Box 148... Mature. Mature shall have the same meaning assigned the term in the Florida Citrus Code, Chapter 601, 1995 Edition, and the Official Rules Affecting the Florida Citrus Industry, in effect as of February...

  8. A Constitutive Model for a Maturing Fibrin Network

    PubMed Central

    van Kempen, Thomas H.S.; Bogaerds, Arjen C.B.; Peters, Gerrit W.M.; van de Vosse, Frans N.

    2014-01-01

    Blood clot formation is crucial to maintain normal physiological conditions but at the same time involved in many diseases. The mechanical properties of the blood clot are important for its functioning but complicated due to the many processes involved. The main structural component of the blood clot is fibrin, a fibrous network that forms within the blood clot, thereby increasing its mechanical rigidity. A constitutive model for the maturing fibrin network is developed that captures the evolving mechanical properties. The model describes the fibrin network as a network of fibers that become thicker in time. Model parameters are related to the structural properties of the network, being the fiber length, bending stiffness, and mass-length ratio. Results are compared with rheometry experiments in which the network maturation is followed in time for various loading frequencies and fibrinogen concentrations. Three parameters are used to capture the mechanical behavior including the mass-length ratio. This parameter agrees with values determined using turbidimetry experiments and is subsequently used to derive the number of protofibrils and fiber radius. The strength of the model is that it describes the mechanical properties of the maturing fibrin network based on it structural quantities. At the same time the model is relatively simple, which makes it suitable for advanced numerical simulations of blood clot formation during flow in blood vessels. PMID:25028892

  9. Estimated maturity status and perceptions of adult autonomy support in youth soccer players.

    PubMed

    Cumming, Sean P; Battista, Rebecca A; Martyn, Standage; Ewing, Martha E; Malina, Robert M

    2006-10-01

    In this study, we examined the relations between biological maturity status, body mass index, age, and perceptions of adult autonomy support in the context of youth soccer. A total of 70 female and 43 male soccer players, aged 9 - 15 years, completed three adult-specific versions (i.e. mother, father, coach) of the perceived autonomy support subscale from the Interpersonal Style Scale. The participants' percent predicted adult stature was used as an estimate of biological maturity status. Multiple linear regression analyses revealed that advanced maturity status in male players predicted lower perceptions of autonomy support from the coach. Maturity status was unrelated to perceptions of autonomy support from the coach in female soccer players, and paternal and maternal autonomy support in male and female players. Age and body mass index were unrelated to perceptions of adult (i.e. coach, mother, father) autonomy support in male and female players.

  10. Mycobacterium avium subspecies impair dendritic cell maturation.

    PubMed

    Basler, Tina; Brumshagen, Christina; Beineke, Andreas; Goethe, Ralph; Bäumer, Wolfgang

    2013-10-01

    Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne's disease, a chronic, granulomatous enteritis of ruminants. Dendritic cells (DC) of the gut are ideally placed to combat invading mycobacteria; however, little is known about their interaction with MAP. Here, we investigated the interaction of MAP and the closely related M. avium ssp. avium (MAA) with murine DC and the effect of infected macrophages on DC maturation. The infection of DC with MAP or MAA induced DC maturation, which differed to that of LPS as maturation was accompanied by higher production of IL-10 and lower production of IL-12. Treatment of maturing DC with supernatants from mycobacteria-infected macrophages resulted in impaired DC maturation, leading to a semi-mature, tolerogenic DC phenotype expressing low levels of MHCII, CD86 and TNF-α after LPS stimulation. Though the cells were not completely differentiated they responded with an increased IL-10 and a decreased IL-12 production. Using recombinant cytokines we provide evidence that the semi-mature DC phenotype results from a combination of secreted cytokines and released antigenic mycobacterial components of the infected macrophage. Our results indicate that MAP and MAA are able to subvert DC function directly by infecting and indirectly via the milieu created by infected macrophages.

  11. Protein syntehsis during soybean seed maturation

    SciTech Connect

    Rosenberg, L.A.; Rinne, R.W.

    1987-04-01

    The authors previous work has demonstrated that physiological and biochemical changes specifically associated with soybean seed maturation can be separated from events associated with seed development. The objective of this study was to determine if soybean seed metabolism is altered during maturation drying at the level of protein synthesis. Seed harvested 35 days after flowering (0% seedling growth) were induced to mature (100% seedling growth) through controlled dehydration. Proteins labeled with (/sup 35/S)-methionine were extracted and analyzed by 1-D PAGE coupled with autoradiography and densitometry. Results show a 31 kD and 128 kD polypeptide synthesized de novo during dehydration and precocious maturation. The same two polypeptides are synthesized during natural dehydration and maturation (>60 days after flowering). Furthermore, these polypeptides persist during rehydration and germination of both precociously and naturally matured seed, but specifically disappear during early seedling growth. The authors are currently investigating the role of protein synthesis during soybean seed maturation and if it is required for establishment of a soybean seedling.

  12. Paraoxonase 1 and HDL maturation.

    PubMed

    Gugliucci, Alejandro; Menini, Teresita

    2015-01-15

    Understanding the kinetics and function of paraoxonase 1 (PON1) is becoming an important issue in atherosclerosis. Low PON1 activity has been consistently linked with an increased risk of major cardiovascular events in the setting of secondary prevention of coronary artery disease. Recent studies have shown that there is a specific interaction of myeloperoxidase (MPO)-apoAI-PON1 on HDL surface that seems to be germane to atherogenesis. MPO specifically inhibits PON1 and PON1 mitigates MPO effects. Surprisingly, very little is known about the routes by which PON1 gets integrated into HDL or its fate during HDL remodeling in the intravascular space. We have developed a method that assesses PON1 activity in the individual HDL subclasses with the aid of which we have shown that PON1 is present across the HDL particle range and preferentially in HDL3, confirming data from ultracentrifugation (UC) studies. Upon HDL maturation ex vivo PON1 is activated and it shows a flux to both smaller and larger HDL particles as well as to VLDL and sdLDL. At the same time apoE, AI and AII are shifted across particle sizes. PON1 activation and flux across HDL particles are blocked by CETP and LCAT inhibitors. In a group of particles with such a complex biology as HDL, knowledge of the interaction between apo-lipoproteins, lipids and enzymes is key for an increased understanding of the yet multiple unknown features of its function. Solving the HDL paradox will necessitate the development of techniques to explore HDL function that are practical and well adapted to clinical studies and eventually become useful in patient monitoring. The confluence of proteomic, functional studies, HDL subclasses, PON1 assays and zymogram will yield data to draw a more elaborate and comprehensive picture of the function of HDL. It must be noted that all these studies are static and conducted in the fasting state. The crucial phase will be achieved when human kinetic studies (both in the fasting and post

  13. Ca2+ signaling differentiation during oocyte maturation.

    PubMed

    Machaca, Khaled

    2007-11-01

    Oocyte maturation is an essential cellular differentiation pathway that prepares the egg for activation at fertilization leading to the initiation of embryogenesis. An integral attribute of oocyte maturation is the remodeling of Ca2+ signaling pathways endowing the egg with the capacity to produce a specialized Ca2+ transient at fertilization that is necessary and sufficient for egg activation. Consequently, mechanistic elucidation of Ca2+ signaling differentiation during oocyte maturation is fundamental to our understanding of egg activation, and offers a glimpse into Ca2+ signaling regulation during the cell cycle.

  14. Assessment of DE-71, a commercial polybrominated diphenyl ether (PBDE) mixture, in the EDSP male and female pubertal protocols.

    PubMed

    Stoker, Tammy E; Laws, Susan C; Crofton, Kevin M; Hedge, Joan M; Ferrell, Janet M; Cooper, Ralph L

    2004-03-01

    DE-71, a commercial mixture, was used to test the sensitivity of the female and male pubertal protocol to detect thyroid active chemicals. These protocols are being evaluated for the U.S. EPA's Endocrine Disruptor Screening Program as part of a Tier I Screening Battery. To examine the ability of these protocols to screen for chemicals that induce the clearance of thyroid hormone, we examined male and female Wistar rats following DE-71 exposure. Rats were gavaged daily with 0, 3, 30, or 60 mg/kg DE in corn oil from postnatal day (PND) 23-53 in the male or PND 22-41 in the female. The temporal effects of DE-71 on liver enzymes and thyroid hormones were measured in another group of males and females following only 5 days of dosing (PND 21 to 26 in females and PND 23 to 28 in males). Serum T4 was significantly decreased at 30 and 60 mg/kg following the 5-day exposures and in the 21-day exposed females. Doses of 3, 30, and 60 mg/kg decreased T4 in 31-day exposed males. Serum T3 was decreased and TSH elevated by 30 and 60 mg/kg in the 31-day exposed males only. Decreased colloid area and increased follicular cell heights (indicative of the hypothyroid state) were observed in thyroids of the 60 mg/kg groups of 20- and 31-day exposed female and males. Increased liver-to-body weight ratios coincided with a significant induction of uridinediphosphate-glucuronosyltransferase (UDGPT; two to four-fold), and ethoxy- and pentoxy-resorufin-O-deethylase (EROD and PROD) at the two highest doses in all exposures. Of the androgen dependent tissues in the 31-day exposed males, seminal vesicle (SV) and ventral prostate (VP) weights were reduced at 60 mg/kg, while testes and epididymal weights were not affected. Preputial separation (PPS) was also significantly delayed by doses of 30 and 60 mg/kg. In the female, the 60 mg/kg dose also caused a significant delay in the age of vaginal opening. Based upon the thyroid hormone response data, this study provides evidence that the 31-day

  15. Assessment of DE-71, a commercial polybrominated diphenyl ether (PBDE) mixture, in the EDSP male and female pubertal protocols.

    PubMed

    Stoker, Tammy E; Laws, Susan C; Crofton, Kevin M; Hedge, Joan M; Ferrell, Janet M; Cooper, Ralph L

    2004-03-01

    DE-71, a commercial mixture, was used to test the sensitivity of the female and male pubertal protocol to detect thyroid active chemicals. These protocols are being evaluated for the U.S. EPA's Endocrine Disruptor Screening Program as part of a Tier I Screening Battery. To examine the ability of these protocols to screen for chemicals that induce the clearance of thyroid hormone, we examined male and female Wistar rats following DE-71 exposure. Rats were gavaged daily with 0, 3, 30, or 60 mg/kg DE in corn oil from postnatal day (PND) 23-53 in the male or PND 22-41 in the female. The temporal effects of DE-71 on liver enzymes and thyroid hormones were measured in another group of males and females following only 5 days of dosing (PND 21 to 26 in females and PND 23 to 28 in males). Serum T4 was significantly decreased at 30 and 60 mg/kg following the 5-day exposures and in the 21-day exposed females. Doses of 3, 30, and 60 mg/kg decreased T4 in 31-day exposed males. Serum T3 was decreased and TSH elevated by 30 and 60 mg/kg in the 31-day exposed males only. Decreased colloid area and increased follicular cell heights (indicative of the hypothyroid state) were observed in thyroids of the 60 mg/kg groups of 20- and 31-day exposed female and males. Increased liver-to-body weight ratios coincided with a significant induction of uridinediphosphate-glucuronosyltransferase (UDGPT; two to four-fold), and ethoxy- and pentoxy-resorufin-O-deethylase (EROD and PROD) at the two highest doses in all exposures. Of the androgen dependent tissues in the 31-day exposed males, seminal vesicle (SV) and ventral prostate (VP) weights were reduced at 60 mg/kg, while testes and epididymal weights were not affected. Preputial separation (PPS) was also significantly delayed by doses of 30 and 60 mg/kg. In the female, the 60 mg/kg dose also caused a significant delay in the age of vaginal opening. Based upon the thyroid hormone response data, this study provides evidence that the 31-day

  16. [Glicemic control in prepubertal and pubertal patients with diabetes type 1 - a one year ambulatory follow-up

    PubMed

    Gomes, M B; Castro, S H; Garfinkel, T; Fernandes, L M; Cunha, E F; Lobão, V I

    2001-01-01

    OBJECTIVE: To evaluate glycemic control in type 1 diabetes mellitus patients followed in 1998. PATIENTS AND METHODS: We studied 38 patients [22 males; age = 10.4 -/+ 4.1 years; 12 (31.6%) prepubertal, 26 (68.4%) pubertal], with diabetes duration of 3.7-/+3.4 years and age of diagnosis of 7.2 -/+ 4.7 years. HbA1c was determined using high-performance liquid chromatography (L-9100 Merck Hitachi, reference value =2.6 to 6.2%). RESULTS: HbA1c was 8.04 -/+ 2.4%, without association with gender and puberty. In the 27 patients with at least two HbA1c determinations, the level of glycemic control changed in 8 (29.6%) and remained the same in 19 (70.4%). From these, glycemic control was poor in 3 (11.1%) and good in 16 (59.3%). Among the patients with good glycemic control, HbA1c was always within reference values in 4 (25%); 7 (43.75%) had at least one HbA1c measurement within these limits; and in 5 (31.25%), all HbA1c measurements were above the upper limit of the reference range. There was no association between the last glycemic control evaluation and the number of HbA1c determinations. The intraindividual coefficient of variation of HbA1c in the group that had at least three HbA1c determinations (n = 19) was 11.2 -/+ 5.6% (P = 0.0000). CONCLUSION: In our study, although most patients presented satisfactory glycemic control during the follow-up period, only 4 patients (14.8%) maintained normal values of HbA1c. The variability of HbA1c must be evaluated when considering the interrelation between glycemic control and evolution to microvascular complications in diabetis.

  17. Gender differences in sagittal standing alignment before pubertal peak growth: the importance of subclassification and implications for spinopelvic loading

    PubMed Central

    Dolphens, Mieke; Cagnie, Barbara; Vleeming, Andry; Vanderstraeten, Guy; Danneels, Lieven

    2013-01-01

    The aim of this study was to analyze gender differences in sagittal standing alignment at pre-peak height velocity age thereby applying a scientifically sound and practically oriented classification scheme for overall standing balance. The study population consisted of healthy boys (n = 639) and girls (n = 557) before pubertal peak growth. During subjects' habitual standing, sagittal plane measures of the spine, pelvis and lower limbs were collected using a clinical screening protocol. With each subject classified as one of three postural types (neutral, sway-back, or leaning-forward), differences in sagittal plane alignment were analyzed between sexes. The results revealed clear differences between genders in each of the postural types. Within the neutral and sway-back postural subgroups, boys presented more forward inclination of the trunk, more thoracic kyphosis and more pelvis backtilt compared with girls. Within the leaning-forward category, girls displayed more forward trunk lean, less thoracic kyphosis and more pelvic anteversion. A state of lumbar segmental hyperextension appeared to exist in female leaning-forward subjects. Our results reveal for the first time that sagittal standing alignment is different between prepubescent boys and girls when subjects are appropriately subclassified, and conversely represent a ‘wash-out effect’ when pooled. When the classification system is applied, gender-specificity in gravity line position is suggested, implying gender-related differences in lever arms and thus load. Present findings may add to our understanding of gender-specific biomechanical challenges posed by habitual posture, and may shed new light on sagittal standing alignment as a possible contributory factor in developmental spinal-pelvic disorders. PMID:24107185

  18. Organizational role for pubertal androgens on adult hypothalamic-pituitary-adrenal sensitivity to testosterone in the male rat.

    PubMed

    Evuarherhe, O; Leggett, J D; Waite, E J; Kershaw, Y M; Atkinson, H C; Lightman, S L

    2009-06-15

    The inhibitory effect of androgens on the hypothalamic-pituitary-adrenal (HPA) axis in basal and stress conditions in adult male rats is well documented. Major sex-related neuroendocrine changes take place during puberty. There is a robust rise in production and secretion of gonadal steroids, which is thought to underlie numerous neural and behavioural changes brought on after puberty. The present study investigated the effect of the pubertal rise in gonadal steroid levels on the subsequent adult corticosterone profile, particularly the sensitivity of the adult HPA axis to testosterone. Animals were castrated either prepubertally (28 days) or in adulthood (11 weeks) and adult animals were subsequently treated with subcutaneous implants containing either testosterone or cholesterol. Using an automated blood sampling system, blood was collected from each freely moving, conscious rat every 10 min (i) over a 24 h period; (ii) in response to 10 min of noise stress, and (iii) following an immunological challenge with lipopolysaccharide (LPS). Analysis revealed that testosterone treatment did not significantly affect overall corticosterone release over the 24 h period in adult animals castrated before puberty in contrast to animals castrated in adulthood in which testosterone significantly suppressed corticosterone secretion. Following either a noise stress or LPS injection, testosterone treatment did not affect the hypothalamic or adrenal stress response in animals castrated prepubertally. Testosterone significantly suppressed the corticotrophin-releasing hormone and arginine vasopressin mRNA as well as the corticosterone response to LPS in castrated animals that had had their testes intact over puberty. These data provide evidence that puberty is a critical organizational period during which rising levels of gonadal steroids programme the sensitivity of the adult HPA axis to gonadal steroids in adulthood.

  19. Yo-Yo Intermittent Endurance Test-Level 1 to monitor changes in aerobic fitness in pre-pubertal boys.

    PubMed

    Fernandes, Luís; Krustrup, Peter; Silva, Gustavo; Rebelo, Antonio; Oliveira, José; Brito, João

    2016-01-01

    The present study aimed to examine the performance and heart rate responses during the Yo-Yo Intermittent Endurance Test-Level 1 (Yo-Yo IE1) in children under the age of 10. One hundred and seven male children (7-9 years) performed the Yo-Yo IE1 at the beginning (M1), middle (M2) and end (M3) of the school year. Data from individual heart rate curves of the Yo-Yo IE1 were analysed in order to detect the inflection point between an initial phase of fast rise in heart rate values and a second phase in which the rise of the heart rate values is much smaller. The distance covered in the Yo-Yo IE1 improved from M1 to M3 (884 ± 496 vs. 1032 ± 596 m; p < 0.05; d = 0.27), with intermediate values for M2 (962 ± 528 m). Peak heart rate (HRpeak) decreased from M1 to M2 and M3 (204 ± 9, 202 ± 9 and 200 ± 9 bpm, respectively; p < 0.05; d = 0.25-0.42). The 7th shuttle of the test (280 m), corresponding to 2.5 min, was identified as the inflection point between the two phases. Also, absolute heart rate at the 7th shuttle decreased progressively throughout the year (185 ± 9, 183 ± 10, and 179 ± 10 bpm; p < 0.05; d = 0.31-0.61). The present study provides evidence of the usefulness of a maximal as well as a submaximal version of Yo-Yo IE1 as a tool to monitor changes in aerobic fitness in pre-pubertal children.

  20. Stirred suspension bioreactors as a novel method to enrich germ cells from pre-pubertal pig testis.

    PubMed

    Dores, C; Rancourt, D; Dobrinski, I

    2015-05-01

    To study spermatogonial stem cells the heterogeneous testicular cell population first needs to be enriched for undifferentiated spermatogonia, which contain the stem cell population. When working with non-rodent models, this step requires working with large numbers of cells. Available cell separation methods rely on differential properties of testicular cell types such as expression of specific cell surface proteins, size, density, or differential adhesion to substrates to separate germ cells from somatic cells. The objective of this study was to develop an approach that allowed germ cell enrichment while providing efficiency of handling large cell numbers. Here, we report the use of stirred suspension bioreactors (SSB) to exploit the adhesion properties of Sertoli cells to enrich cells obtained from pre-pubertal porcine testes for undifferentiated spermatogonia. We also compared the bioreactor approach with an established differential plating method and the combination of both: SSB followed by differential plating. After 66 h of culture, germ cell enrichment in SSBs provided 7.3 ± 1.0-fold (n = 9), differential plating 9.8 ± 2.4-fold (n = 6) and combination of both methods resulted in 9.1 ± 0.3-fold enrichment of germ cells from the initial germ cell population (n = 3). To document functionality of cells recovered from the bioreactor, we demonstrated that cells retained their functional ability to reassemble seminiferous tubules de novo after grafting to mouse hosts and to support spermatogenesis. These results demonstrate that the SSB allows enrichment of germ cells in a controlled and scalable environment providing an efficient method when handling large cell numbers while reducing variability owing to handling.