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Sample records for age pubertal stage

  1. 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

  2. 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…

  3. 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

  4. 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

    Inhibin B levels were measured in serum from 400 healthy Danish prepubertal, pubertal, and adolescent males, aged 6-20 yr, in a cross-sectional study using a recently developed immunoassay that is specific for inhibin B, the physiologically important inhibin form in men. In addition, serum levels of FSH, LH, testosterone, and estradiol levels were measured. Serum levels of inhibin B, FSH, LH, testosterone, and estradiol all increased significantly between stages I and II of puberty. From stage II of puberty the inhibin B level was relatively constant, whereas the FSH level continued to increase between stages II and III. From stage III of puberty the FSH level was also relatively constant, although there was a nonsignificant trend of slightly decreased FSH levels at pubertal stage V compared to stage IV. The levels of serum LH, testosterone, and estradiol increased progressively throughout puberty. In prepubertal boys younger than 9 yr, there were no correlation between inhibin B and the other three hormones. In prepubertal boys older than 9 yr, a significant positive correlation was observed between inhibin B and FSH, LH, and testosterone. However, at this pubertal stage, each hormone correlated strongly with age, and when the effect of age was taken into account, only the partial correlation between inhibin B and LH/testosterone remained statistically significant. At stage II of puberty, the positive partial correlation between inhibin B and LH/testosterone was still present. At stage III of puberty, an negative partial correlation between inhibin B and FSH, LH, and estradiol was present, whereas no correlation between inhibin B and testosterone could be observed from stage III onward. The negative correlation between inhibin B and FSH persisted from stage III of puberty onward, whereas the correlation between inhibin B and LH and between inhibin B and estradiol was nonsignificant at stages IV and V of puberty. In conclusion, in boys, serum inhibin B levels

  5. 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.

  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. 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.

  8. 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…

  9. 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

  10. 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.

  11. 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

  12. 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.

  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. 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.

  15. 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.

  16. 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)

  17. Parental education level is associated with clustering of metabolic risk factors in adolescents independently of cardiorespiratory fitness, adherence to the Mediterranean diet, or pubertal stage.

    PubMed

    Santos, Rute; Moreira, Carla; Abreu, Sandra; Lopes, Luís; Ruiz, Jonatan R; Moreira, Pedro; Silva, Pedro; Mota, Jorge

    2014-08-01

    Few studies have reported associations between clustering metabolic risk factors and socioeconomic status (SES) in youth. This study aimed to analyze the association between clustering metabolic risk factors and SES in adolescents. It was hypothesized that SES is inversely related to clustering metabolic risk factors. This 2009 cross-sectional school-based study investigated 517 Portuguese adolescents ages 15-18 years. The study considered the age- and sex-adjusted z-scores for the ratio of total cholesterol/high-density lipoprotein, homeostasis model, triglycerides, and systolic blood pressure, and a metabolic risk score was constructed by summing all the z-scores (≥1 standard deviation was considered high risk). Cardiorespiratory fitness was estimated by the 20 m shuttle-run test and dietary intake by a food frequency questionnaire. The best of parental education was used as a proxy measure of SES. The results showed that adolescents with low SES were more likely to have a high metabolic risk score (odds ratio [OR], 1.96; p < 0.020) regardless of cardiorespiratory fitness, adherence to the Mediterranean diet, or pubertal stage. In conclusion, a lower SES was associated with increased risk for a high metabolic risk score among Azorean adolescents after adjustment for pubertal stage, adherence to the Mediterranean diet, and cardiorespiratory fitness. Future health-promotion strategies among Azorean adolescents should consider the impact of SES on their health.

  18. 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

  19. 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.

  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. 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.

  2. 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…

  3. 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

  4. 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

  5. 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

  6. 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...

  7. 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

  8. 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.

  9. 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

  10. Effects of 2,4-dichlorophenoxyacetic acid on the ventral prostate of rats during the peri-pubertal, pubertal and adult stage.

    PubMed

    Pochettino, Arístides A; Hapon, María Belén; Biolatto, Silvana M; Madariaga, María José; Jahn, Graciela A; Konjuh, Cintia N

    2016-10-01

    The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used on a wide variety of terrestrial and aquatic broadleaf weeds. 2,4-D has been shown to produce a wide range of adverse effects on animal and human health. The aim of the current study was to evaluate the effects of pre- and postnatal exposure to 2,4-D on rat ventral prostate (VP). Pregnant rats were exposed daily to oral doses of 70 mg/kg/day of 2,4-D from 16 days of gestation up to 23 days after delivery. Then, the treated groups (n = 8) were fed with a 2,4-D added diet until sacrificed by decapitation on postnatal day (PND) 45, 60, or 90. Morphometric studies were performed and androgen receptor (AR) protein levels in the VP were determined. AR, insulin-like growth factor-I (IGF-1) and insulin-like growth factor-I receptor (IGF-1R) mRNA expression in the VP along with testosterone (T), dihydroxytestosterone (DHT), growth hormone (GH) and IGF-1 serum levels were also determined to ascertain whether these parameters were differentially affected. Results of this study showed that 2,4-D exposure during gestation and until adulthood altered development of the prostate gland in male rats, delaying it at early ages while increasing its size in adults, indicate that 2,4-D could behave as endocrine disruptors (EDs). PMID:26759115

  11. 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 ageage 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

  12. 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

  13. 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

  14. 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.

  15. 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 =…

  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. 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

  18. Effect of intensified feeding of heifer calves on growth, pubertal age, calving age, milk yield, and economics.

    PubMed

    Davis Rincker, L E; Vandehaar, M J; Wolf, C A; Liesman, J S; Chapin, L T; Weber Nielsen, M S

    2011-07-01

    The objective of this study was to determine if increasing the energy and protein intake of heifer calves would affect growth rates, age at puberty, age at calving, and first lactation milk yield. A second objective was to perform an economic analysis of this feeding program using feed costs, number of nonproductive days, and milk yield data. Holstein heifer calves born at the Michigan State Dairy Cattle Teaching and Research Center were randomly assigned to 1 of 2 dietary treatments (n=40/treatment) that continued from 2 d of age until weaning at 42 d of age. The conventional diet consisted of a standard milk replacer [21.5% crude protein (CP), 21.5% fat] fed at 1.2% of body weight (BW) on a dry matter basis and starter grain (19.9% CP) to attain 0.45 kg of daily gain. The intensive diet consisted of a high-protein milk replacer (30.6% CP, 16.1% fat) fed at 2.1% of BW on a dry matter basis and starter grain (24.3% CP) to achieve 0.68 kg of daily gain. Calves were gradually weaned from milk replacer by decreasing the amount offered for 5 and 12 d before weaning for the conventional and intensive diets, respectively. All calves were completely weaned at 42 d of age and kept in hutches to monitor individual starter consumption in the early postweaning period. Starting from 8 wk of age, heifers on both treatments were fed and managed similarly for the duration of the study. Body weight and skeletal measurements were taken weekly until 8 wk of age, and once every 4 wk thereafter until calving. Calves consuming the intensive diet were heavier, taller, and wider at weaning. The difference in withers height and hip width was carried over into the early post-weaning period, but a BW difference was no longer evident by 12 wk of age. Calves fed the intensive diet were younger and lighter at the onset of puberty. Heifers fed the high-energy and protein diet were 15 d younger at conception and 14 d younger at calving than heifers fed the conventional diet. Body weight after

  19. 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.

  20. 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…

  1. 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

  2. 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.

  3. 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

  4. 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…

  5. 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…

  6. 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

  7. 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

  8. 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.

  9. Ages & Stages Questionnaire–Brazil–2011

    PubMed Central

    Santana, Cristina M. T.; Filgueiras, Alberto; Landeira-Fernandez, J.

    2015-01-01

    Introduction. Professionals who assess early childhood development highly benefit from reliable development screening measures. The Ages & Stages Questionnaire was adapted Brazil in 2010 and named ASQ-BR. Modifications in some items were required to improve the instrument’s psychometric properties. The present study modified the ASQ-BR to verify if those changes increase its characteristics. Method. This study researched 67 522 children from 972 public day care centers and preschools. Changes in items were made considering Cronbach’s α and item-to-total correlations. Reliability, dimensionality, and item-to-total correlations were calculated. Results. Regarding dimensionality, 86.2% of the scales in ASQ-BR-2011 were unidimensional. Internal consistency showed improvement from 2010 to 2011: 53.8% of the scales increased the α statistics against 41.2% that decreased, and 5.0% remained the same. Finally, 65.2% of the modified items showed improvement. Conclusions. Overall, the instrument’s psychometrics improved from 2010 to 2011, especially in the personal/social domain. However, it still leaves room for improvement in future studies. PMID:27335984

  10. 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...

  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. 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.

  13. 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

  14. 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

  15. 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

  16. Development: Ages & Stages--Emerging Physical Skills

    ERIC Educational Resources Information Center

    Poole, Carla; Miller, Susan A.; Church, Ellen Booth

    2005-01-01

    In this article, the authors discuss how children develop their motor skills at different age levels. Newborn's movements are jerky and uncoordinated. Spending lots of floor time with a baby lying on her back or stomach helps her develop coordination, balance, and muscle strength during her earliest months. As locomotion enters a baby's life, she…

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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

    STUDY QUESTION Does phthalate exposure during early childhood alter the timing of pubertal development in girls? SUMMARY ANSWER Urinary concentrations of high-molecular weight phthalate (high-MWP) metabolites are associated with later pubarche. WHAT IS KNOWN ALREADY Phthalates are anti-androgenic environmental agents known to alter early development, with possible effects on pubertal onset. STUDY DESIGN, SIZE, AND DURATION This multi-ethnic study included 1239 girls from New York City, greater Cincinnati, and the San Francisco Bay Area who were 6–8 years old at enrollment (2004–2007) and who were followed until 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS Phthalate metabolites were measured in urine collected at enrollment from 1170 girls; concentrations ranged from <1 to >10 000 µg/l. Breast and pubic hair stages and body size were assessed one to two times annually to determine the age at transition from stage 1 to 2 for breast and pubic hair development. Associations between exposures and pubertal ages were estimated using Cox proportional hazard ratios (HR) with 95% confidence intervals (CI) and survival analyses. Associations were examined with respect to age-specific body mass-index percentile, one of the strongest predictors of pubertal onset. MAIN RESULTS AND THE ROLE OF CHANCE Urinary concentrations of high-MWP including di(2-ethylhexyl) phthalate (ΣDEHP) metabolites were associated with later pubic hair development during 7 years of observation. The relationship was linear and was stronger among normal-weight girls. Among normal-weight girls, age at pubic hair stage 2 (PH2) was 9.5 months older for girls in the fifth compared with the first quintile of urinary ΣDEHP (medians: 510 and 59 µg/g creatinine, respectively; adjusted HR 0.70, CI 0.53–0.93, P-trend 0.005. Age at first breast development was older for fifth quintile of mono-benzyl phthalate versus first (HR 0.83, CI 0.68–1.02; P-trend 0.018). No associations were observed between low

  2. 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

  3. 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

  4. 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

  5. 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.

  6. Inhibin B, follicle stimulating hormone, luteinizing hormone and testosterone during childhood and puberty in males: changes in serum concentrations in relation to age and stage of puberty.

    PubMed

    Chada, M; Průsa, R; Bronský, J; Kotaska, K; Sídlová, K; Pechová, M; Lisá, L

    2003-01-01

    Inhibin B is a gonadal dimeric polypeptide hormone that regulates synthesis and secretion of follicle stimulating hormone (FSH) in a negative feedback loop. The aim of the present study was to determine changes in serum inhibin B, gonadotropins and testosterone concentrations during childhood and puberty in males. We studied the relationship between circulating inhibin B, gonadotropins and testosterone in serum of healthy boys during the first two years of life and then in pubertal development. Using a recently developed two-side enzyme-linked immunosorbent assay (ELISA), inhibin B levels were measured in the serum of 78 healthy boys divided into eleven age groups from birth to the end of pubertal development. In addition, serum levels of gonadotropins and testosterone were measured. Serum inhibin B, gonadotropins and testosterone increased during the first months of postnatal life. A peak in serum inhibin B and gonadotropins concentrations was observed around 3-4 months of age. There was a significant positive correlation between serum inhibin B and gonadotropins and testosterone levels during the first 2 years of life. After this early increase, serum inhibin B, gonadotropins and testosterone levels decreased significantly and remained low until puberty followed by an increase beginning with the onset of puberty. Serum levels of inhibin B reached a peak at stage G3 of puberty. Around midpuberty, inhibin B lost its positive correlation with luteinizing hormone (LH) and testosterone from early puberty, and developed a strong negative correlation with FSH, which persisted into adulthood. We conclude that inhibin B plays a key role in the regulation of the hypothalamic-pituitary-gonadal hormonal axis during male childhood and pubertal development. Inhibin B is a direct marker of the presence and function of Sertoli cells and appears to reflect testicular function in boys.

  7. 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

  8. 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…

  9. 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…

  10. 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.

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. Age or stage structure? A comparison of dynamic outcomes from discrete age- and stage-structured population models.

    PubMed

    Wikan, Arild

    2012-06-01

    Discrete stage-structured density-dependent and discrete age-structured density-dependent population models are considered. Regarding the former, we prove that the model at hand is permanent (i.e., that the population will neither go extinct nor exhibit explosive oscillations) and given density dependent fecundity terms we also show that species with delayed semelparous life histories tend to be more stable than species which possess precocious semelparous life histories. Moreover, our findings together with results obtained from other stage-structured models seem to illustrate a fairly general ecological principle, namely that iteroparous species are more stable than semelparous species. Our analysis of various age-structured models does not necessarily support the conclusions above. In fact, species with precocious life histories now appear to possess better stability properties than species with delayed life histories, especially in the iteroparous case. We also show that there are dynamical outcomes from semelparous age-structured models which we are not able to capture in corresponding stage-structured cases. Finally, both age- and stage-structured population models may generate periodic dynamics of low period (either exact or approximate). The important prerequisite is to assume density-dependent survival probabilities. PMID:22297621

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. Age and correlation of California Paleogene benthic foraminiferal stages

    USGS Publications Warehouse

    Poore, Richard Z.

    1980-01-01

    Comparisons of age determinations and correlations derived from calcareous plankton with those derived from benthic foraminifers in a number of sections in California show significant overlap in time of the Ynezian through the Ulatisian Stages. Thus interbasin time correlations deduced from these stage assignments must be treated with caution. Calcareous plankton occasionally associated with benthic foraminifers diagnostic of the Narizian through the Zemorrian Stages indicate that the Narizian-Refugian boundary is within the upper Eocene of international usage and that the Refugian is entirely upper Eocene. Overlap of the Narizian and the Refugian appears to be minimal. The Zemorrian correlates, mostly, with the Oligocene, although the upper limit of the Zemorrian might be in the lower Miocene.

  3. Automatic age-related macular degeneration detection and staging

    NASA Astrophysics Data System (ADS)

    van Grinsven, Mark J. J. P.; Lechanteur, Yara T. E.; van de Ven, Johannes P. H.; van Ginneken, Bram; Theelen, Thomas; Sánchez, Clara I.

    2013-03-01

    Age-related macular degeneration (AMD) is a degenerative disorder of the central part of the retina, which mainly affects older people and leads to permanent loss of vision in advanced stages of the disease. AMD grading of non-advanced AMD patients allows risk assessment for the development of advanced AMD and enables timely treatment of patients, to prevent vision loss. AMD grading is currently performed manually on color fundus images, which is time consuming and expensive. In this paper, we propose a supervised classification method to distinguish patients at high risk to develop advanced AMD from low risk patients and provide an exact AMD stage determination. The method is based on the analysis of the number and size of drusen on color fundus images, as drusen are the early characteristics of AMD. An automatic drusen detection algorithm is used to detect all drusen. A weighted histogram of the detected drusen is constructed to summarize the drusen extension and size and fed into a random forest classifier in order to separate low risk from high risk patients and to allow exact AMD stage determination. Experiments showed that the proposed method achieved similar performance as human observers in distinguishing low risk from high risk AMD patients, obtaining areas under the Receiver Operating Characteristic curve of 0.929 and 0.934. A weighted kappa agreement of 0.641 and 0.622 versus two observers were obtained for AMD stage evaluation. Our method allows for quick and reliable AMD staging at low costs.

  4. 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…

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Sex- and age-dependent activity of glutathione peroxidase in reproductive organs in pre- and post-pubertal cattle in relation to total antioxidant capacity.

    PubMed

    Kankofer, M; Wawrzykowski, J; Giergiel, M

    2013-08-01

    Antioxidative/oxidative balance is crucial for proper functioning of cells and tissues. It is suggested that this balance can be partly controlled by sex steroid hormones and in consequence can exhibit age- and sex-related dependency. The aim of present study was to describe sex- and age-related changes in the activity of glutathione peroxidase (GSH-Px) with respect to total antioxidant activity (TAC) in reproductive organs of cattle. Biological samples were collected from slaughterhouse and comprised of ovaries, uterus, testes as well as livers as reference tissue. Animals were divided into group of bulls (aged between 13 and 24 months; n = 12), cows (aged between 14 and 27 months; n = 12) and female calves (aged between 2 weeks and 2 months; n = 12). Examined parameters were determined spectrophotometrically and the presence of GSH-Px isoform was confirmed by Western blotting technique. Activity of GSH-Px in genital tissues regardless of sex was significantly higher than in livers, while TAC showed opposite relationship. The differences in antioxidative parameters between testes and mature ovaries (e.g. GSH-Px-1.42 ± 0.47 nkat/mg prot vs. 1.08 ± 0.24 and 1.15 ± 0.23) were noticed as well as in chosen values between cows and female calves. Western blotting allowed the detection of cytosolic GSH-Px in all examined tissues with molecular weight around 21 kDa as monomer and around 84 kDa as tetramer depending on conditions of electrophoresis. The results may confirm the influence and regulatory role of sex steroid hormones on GSH-Px activity because the alterations were sex and age dependent. PMID:23740597

  11. Sex- and age-dependent activity of glutathione peroxidase in reproductive organs in pre- and post-pubertal cattle in relation to total antioxidant capacity.

    PubMed

    Kankofer, M; Wawrzykowski, J; Giergiel, M

    2013-08-01

    Antioxidative/oxidative balance is crucial for proper functioning of cells and tissues. It is suggested that this balance can be partly controlled by sex steroid hormones and in consequence can exhibit age- and sex-related dependency. The aim of present study was to describe sex- and age-related changes in the activity of glutathione peroxidase (GSH-Px) with respect to total antioxidant activity (TAC) in reproductive organs of cattle. Biological samples were collected from slaughterhouse and comprised of ovaries, uterus, testes as well as livers as reference tissue. Animals were divided into group of bulls (aged between 13 and 24 months; n = 12), cows (aged between 14 and 27 months; n = 12) and female calves (aged between 2 weeks and 2 months; n = 12). Examined parameters were determined spectrophotometrically and the presence of GSH-Px isoform was confirmed by Western blotting technique. Activity of GSH-Px in genital tissues regardless of sex was significantly higher than in livers, while TAC showed opposite relationship. The differences in antioxidative parameters between testes and mature ovaries (e.g. GSH-Px-1.42 ± 0.47 nkat/mg prot vs. 1.08 ± 0.24 and 1.15 ± 0.23) were noticed as well as in chosen values between cows and female calves. Western blotting allowed the detection of cytosolic GSH-Px in all examined tissues with molecular weight around 21 kDa as monomer and around 84 kDa as tetramer depending on conditions of electrophoresis. The results may confirm the influence and regulatory role of sex steroid hormones on GSH-Px activity because the alterations were sex and age dependent.

  12. 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.

  13. 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)

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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…

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. The roles of puberty and age in explaining the diminished effectiveness of parental buffering of HPA reactivity and recovery in adolescence.

    PubMed

    Doom, Jenalee R; Hostinar, Camelia E; VanZomeren-Dohm, Adrienne A; Gunnar, Megan R

    2015-09-01

    Parental support is a powerful regulator of stress and fear responses for infants and children, but recent evidence suggests it may be an ineffective stress buffer for adolescents. The mechanisms underlying this developmental shift are not well-understood. The goal of the present study was to examine the independent and joint contributions of pubertal status and chronological age in explaining this shift. A sample of 75 typically developing youth (M age=12.95 years, SD=0.70, range=11.7-14.6 years; 37 females) was recruited to complete a modified Trier Social Stress Test (TSST-M) in the laboratory. Participants were recruited in such a way as to disentangle pubertal stage and chronological age by phone screening for markers of pubertal stage and then recruiting roughly equal numbers of younger and older, pre/early and mid/late pubertal youth who were then randomly assigned within groups to condition. The TSST-M was used as the stressor and youth prepared either with their parent or stranger (parent condition: N=39). Pubertal stage was confirmed by the Petersen Pubertal Development Scale at the time of testing and treated, along with chronological age, as a continuous variable in the analyses. The results revealed an interaction of pubertal stage and support condition for cortisol reactivity to the TSST-M such that preparing for the speech with the parent became a less potent buffer of the HPA axis as pubertal stage increased. Age did not interact with condition in predicting cortisol reactivity. In contrast, the parent's presence during speech preparation decreased in its effectiveness to hasten recovery of the HPA axis as children got older, but pubertal stage was not predictive of recovery rate. These patterns were specific to cortisol and were not observed with salivary alpha-amylase levels or subjective stress ratings for the task. These analyses suggest that the switch away from using parents as social buffers may be the result of neurobiological mechanisms

  5. The Roles of Puberty and Age in Explaining the Diminished Effectiveness of Parental Buffering of HPA Reactivity and Recovery in Adolescence

    PubMed Central

    Doom, Jenalee R.; Hostinar, Camelia E.; VanZomeren-Dohm, Adrienne A.; Gunnar, Megan R.

    2015-01-01

    Parental support is a powerful regulator of stress and fear responses for infants and children, but recent evidence suggests it may be an ineffective stress buffer for adolescents. The mechanisms underlying this developmental shift are not well-understood. The goal of the present study was to examine the independent and joint contributions of pubertal status and chronological age in explaining this shift. A sample of 75 typically-developing youth (M age = 12.95 years, SD = 0.70, range = 11.7–14.6 years; 37 females) was recruited to complete a modified Trier Social Stress Test (TSST-M) in the laboratory. Participants were recruited in such a way as to disentangle pubertal stage and chronological age by phone screening for markers of pubertal stage and then recruiting roughly equal numbers of younger and older, pre/early and mid/late pubertal youth who were then randomly assigned within groups to condition. The TSST-M was used as the stressor and youth prepared either with their parent or stranger (parent condition: N = 39). Pubertal stage was confirmed by the Petersen Pubertal Development Scale at the time of testing and treated, along with chronological age, as a continuous variable in the analyses. The results revealed an interaction of pubertal stage and support condition for cortisol reactivity to the TSST-M such that preparing for the speech with the parent became a less potent buffer of the HPA axis as pubertal stage increased. Age did not interact with condition in predicting cortisol reactivity. In contrast, the parent’s presence during speech preparation decreased in its effectiveness to hasten recovery of the HPA axis as children got older, but pubertal stage was not predictive of recovery rate. These patterns were specific to cortisol and were not observed with salivary alpha-amylase levels or subjective stress ratings for the task. These analyses suggest that the switch away from using parents as social buffers may be the result of neurobiological

  6. 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

  7. 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

  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. 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.

  10. 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…

  11. Dental age estimation from the developmental stage of the third molars in western Chinese population.

    PubMed

    Li, Guo; Ren, Jiayin; Zhao, Shuping; Liu, Yuanyuan; Li, Na; Wu, Wanhong; Yuan, Shanshan; Wang, Hu

    2012-06-10

    The purpose of this study is to provide reference data about estimating dental age from third molars of the western Chinese population for comparing with other populations and being applied to the age estimation of western Chinese juveniles and adolescents. A total of 2078 digital panoramic radiographs of 989 male and 1089 female Chinese subjects aged between 5 and 23 years were examined. The mineralization status of the third molars was assessed using the formation stages described by Demirjian et al. with two modifications. The results showed that the development of third molars in the western Chinese population was likely to begin at age 5 in both males and females. The third molars 28 and 48 showed significantly higher frequency in females than in males. The third molars 18 in the stage 1, 38 in the stages 1, A and G, and 48 in the stage H showed significantly older average age in females than in males. The Demirjian's stages C and D could be used as a reference stage to determine dichotomously whether a western Chinese is more likely to be under or above age 14 or 16, respectively. This study provided reference data for the age estimation of western Chinese juveniles and adolescents by the mineralization stages of the third molar. Apart from forensic age determination in living subjects, the presented reference data can also be used for age estimations of unidentified corpses and skeletons.

  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. 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.

  14. Mental Health Problems during Puberty: Tanner Stage-Related Differences in Specific Symptoms. The TRAILS Study

    ERIC Educational Resources Information Center

    Oldehinkel, Albertine J.; Verhulst, Frank C.; Ormel, Johan

    2011-01-01

    The aim of this study was to investigate associations between specific mental health problems and pubertal stage in (pre)adolescents participating in the Dutch prospective cohort study TRAILS (first assessment: N = 2230, age 11.09 [plus or minus] 0.56, 50.8% girls; second assessment: N = 2149, age 13.56 [plus or minus] 0.53, 51.0% girls). Mental…

  15. 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

  16. 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

  17. 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

  18. "Life Stage-Specific" Variations in Performance in Response to Age Stereotypes

    ERIC Educational Resources Information Center

    Hehman, Jessica A.; Bugental, Daphne Blunt

    2013-01-01

    In a test of life stage-specific responses to age-based stigma, older (n = 54, ages 62-92) and younger (n = 81, ages 17-22) adults were told that a task (Weschler Adult Intelligence Scale-III block design) required either (a) speed/contemporary knowledge (YA; "youth advantage") or (b) life experience/wisdom (OA; "age…

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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…

  4. 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…

  5. 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…

  6. 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…

  7. 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.…

  8. 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…

  9. 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

  10. Median ages at stages of sexual maturity and excess weight in school children

    PubMed Central

    2013-01-01

    Background We aimed to estimate the median ages at specific stages of sexual maturity stratified by excess weight in boys and girls. Materials and method This was a cross-sectional study made in 2007 in Florianopolis, Brazil, with 2,339 schoolchildren between 8 to 14 years of age (1,107 boys) selected at random in two steps (by region and type of school). The schoolchildren were divided into: i) those with excess weight and ii) those without excess weight, according to the WHO 2007 cut-off points for gender and age. Sexual maturity was self-evaluated by the subjects according to the Tanner sexual development stages, and utilizing median ages for the genitalia, breasts, and pubic hair stages. Results In the boys with excess weight, precocity was observed in the stages 4 for genitals and pubic hair and 2 for pubic hair, with the values for excess and normal weight. The median ages at the beginning of puberty (stage 2–sexual development) for boys and girls in Florianopolis were 10.8 and 10.3 years, respectively. Conclusion Excess weight is associated with lower median ages in the sexual maturity stages in boys and girls and that it should be taken into account when evaluating sexual maturity in children and adolescents. PMID:24139334

  11. 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

  12. 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…

  13. How Applicable Are "Ages and Stages Questionnaires" for Use with Turkish Children?

    ERIC Educational Resources Information Center

    Kapci, Emine Gul; Kucuker, Sevgi; Uslu, Runa I.

    2010-01-01

    The majority of eligible children cannot access early intervention services in Turkey, often because they are not assessed. The authors adapted the "Ages and Stages Questionnaires" (ASQ) for Turkish children ages 3 to 72 months. Study participants consisted of 375 children who were classified as at risk for developmental delays, 564 children…

  14. RACIAL DISPARITIES IN BREAST CANCER SURVIVAL: AN ANALYSIS BY AGE AND STAGE

    PubMed Central

    Deshpande, Anjali D.; Jeffe, Donna B.; Gnerlich, Jennifer; Iqbal, Ayesha Z.; Thummalakunta, Abhishek; Margenthaler, Julie A.

    2011-01-01

    Background Black women often present with advanced-stage breast cancer compared with White women, which may result in the observed higher mortality among Black women. Age-related factors (e.g., comorbidity) also affect mortality. Whether racial disparities in mortality are evident within age and/or stage groups has not been reported, and risk factors for greater mortality among Black women are not well defined. Methods Using the 1988–2003 Surveillance, Epidemiology, and End Results (SEER) Program data, we conducted a retrospective, population-based cohort study to compare overall and stage-specific breast-cancer mortality between Black and White women within each age (<40, 40–49, 50–64, and 65+) and stage (stage 0–IV and unstaged) group at diagnosis. Cox regression models calculated unadjusted and adjusted hazard ratios (HR) and 95% confidence intervals (CI), the latter controlling for potential confounders of the relationship between race and survival. Results In the 1988–2003 SEER data, 20,424 Black and 204,506 White women were diagnosed with first primary breast cancer. In unadjusted models, Black women were more likely than White women to die from breast cancer (HR: 1.90, 95% CI: 1.83–1.96) and from all causes (HR: 1.52, 95% CI: 1.48–1.55) during follow-up. In models stratified by age and stage, Black women were at increased risk of breast-cancer-specific mortality within each stage group among women <65 years. Conclusion Racial disparities in breast-cancer-specific mortality were predominantly observed within each stage at diagnosis among women <65 years old. This greater mortality risk for Black women was largely not observed among women ≥65 years of age. PMID:19084242

  15. 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.

  16. Reassessing the NTCTCS Staging Systems for Differentiated Thyroid Cancer, Including Age at Diagnosis

    PubMed Central

    McLeod, Donald S.A.; Jonklaas, Jacqueline; Brierley, James D.; Ain, Kenneth B.; Cooper, David S.; Fein, Henry G.; Haugen, Bryan R.; Ladenson, Paul W.; Magner, James; Ross, Douglas S.; Skarulis, Monica C.; Steward, David L.; Xing, Mingzhao; Litofsky, Danielle R.; Maxon, Harry R.

    2015-01-01

    Background: Thyroid cancer is unique for having age as a staging variable. Recently, the commonly used age cut-point of 45 years has been questioned. Objective: This study assessed alternate staging systems on the outcome of overall survival, and compared these with current National Thyroid Cancer Treatment Cooperative Study (NTCTCS) staging systems for papillary and follicular thyroid cancer. Methods: A total of 4721 patients with differentiated thyroid cancer were assessed. Five potential alternate staging systems were generated at age cut-points in five-year increments from 35 to 70 years, and tested for model discrimination (Harrell's C-statistic) and calibration (R2). The best five models for papillary and follicular cancer were further tested with bootstrap resampling and significance testing for discrimination. Results: The best five alternate papillary cancer systems had age cut-points of 45–50 years, with the highest scoring model using 50 years. No significant difference in C-statistic was found between the best alternate and current NTCTCS systems (p = 0.200). The best five alternate follicular cancer systems had age cut-points of 50–55 years, with the highest scoring model using 50 years. All five best alternate staging systems performed better compared with the current system (p = 0.003–0.035). There was no significant difference in discrimination between the best alternate system (cut-point age 50 years) and the best system of cut-point age 45 years (p = 0.197). Conclusions: No alternate papillary cancer systems assessed were significantly better than the current system. New alternate staging systems for follicular cancer appear to be better than the current NTCTCS system, although they require external validation. PMID:26203804

  17. DNA methylation of LINE-1 and Alu repetitive elements in relation to sex hormones and pubertal timing in Mexican-American children

    PubMed Central

    Huen, Karen; Harley, Kim; Kogut, Katherine; Rauch, Stephen; Eskenazi, Brenda; Holland, Nina

    2015-01-01

    Background The molecular mechanisms linking environmental exposures to earlier pubertal development are not well characterized. Epigenetics may play an important role, but data on the relationship between epigenetic marks and puberty, particularly in humans, is limited. Methods We used pyrosequencing to measure Alu and long interspersed nucleotide elements (LINE-1) methylation in DNA isolated from whole blood samples collected from newborns and 9-year-old children (n=266). Tanner staging was completed six times between ages 9 and 12 years to determine pubertal status, and hormone levels were measured in 12-year-old boys. Results Among girls, we observed a suggestive trend of increased odds of breast and pubic hair development with higher Alu and LINE-1 methylation in 9-year-old blood, respectively. The strongest association identified was an inverse association of LINE-1 methylation in 9-year-old girls with odds of experiencing menarche by age 12 (OR(95%CI): 0.63(0.46,0.87); p=0.005). We observed a consistent inverse relationship for Alu and LINE-1 methylation at 9 years with luteinizing hormone (LH), testosterone and follicle stimulating hormone levels in boys but it was only significant between LINE-1 and LH. Conclusion DNA methylation of Alu and LINE-1 may be involved in puberty initiation and development. This relationship should be confirmed in future studies. PMID:26882368

  18. Differential effect of age, gender and puberty on bone formation rate assessed by measurement of bone-specific alkaline phosphatase in healthy Italian children and adolescents.

    PubMed

    Mora, Stefano; Cafarelli, Laura; Erba, Paola; Puzzovio, Maria; Zamproni, Ilaria; Giacomet, Vania; Viganò, Alessandra

    2009-01-01

    Bones undergo intensive modeling during growth, a process involving both formation and resorption processes. Bone formation can be accurately monitored by measurements of bone-specific alkaline phosphatase (BAP) in serum. The lack of appropriate reference values has hampered the use of BAP in pediatric subjects. The purposes of the present study were to verify the effect of age, gender, and puberty on BAP concentration in healthy children, and to generate reference curves. Morning blood samples were collected from 239 healthy children and adolescents (113 boys), aged 4.5-20.9 years. Anthropometric measurements and pubertal stage were recorded. Blood samples were also obtained from 37 healthy young adults (13 men), aged 21.5-30.2 years. BAP concentration varied significantly with age, showing a peak at age 10-12 years in girls and 12-14 years in boys. Prepubertal concentration of BAP was six- to sevenfold higher than in healthy adults. We observed significantly higher BAP values at the beginning of puberty (stage II) compared to prepubertal stage in both sexes. The effect of puberty was independent from age and gender. We demonstrated that BAP serum concentration varies with age in children and adolescents, and we provided equations to calculate reference values. Because BAP concentrations vary markedly according to the pubertal stage, the values of BAP obtained in single patients should be compared to reference considering not only age and sex, but also the stage of pubertal development.

  19. Recent decline in prostate cancer incidence in the United States, by age, stage, and Gleason score.

    PubMed

    Herget, Kimberly A; Patel, Darshan P; Hanson, Heidi A; Sweeney, Carol; Lowrance, William T

    2016-01-01

    Prostate cancer incidence is sensitive to screening practices, however the impact of recent screening recommendations from the United States Preventative Services Task Force on prostate cancer incidence by age, stage, race, and Gleason score is unknown. This study described the timing and magnitude of changes in prostate cancer incidence trends in the United States by month of diagnosis, and evaluated trends by age, Gleason score, and stage at diagnosis. We analyzed prostate cancer incidence trends using Surveillance, Epidemiology, and End Results (SEER) program data for men diagnosed with invasive prostate cancer from 2007 through 2012. JoinPoint analysis was used to detect changes in the rate of annual percent change (APC) in prostate cancer incidence for all diagnoses and by age, Gleason score, race, and stage. Prostate cancer incidence declined at an estimated -19.6% APC beginning May 2011. This decline was observed in all age groups. Low-grade tumors (Gleason score ≤6) showed a steeper decline (-29.1% APC) than high-grade tumors (Gleason score 8-10: -10.8% APC). Only stage I/II and stage III tumors saw declines (-24.2% and -16.7% APC, respectively). A sharp decline in prostate cancer incidence began before release of the United States Preventative Services Task Force October 2011 draft and May 2012 final screening recommendation. The greatest change occurred with incidence of low-grade tumors, although there is concern that some high-grade tumors may now go undetected.

  20. Estimation of legal age using calcification stages of third molars in living individuals.

    PubMed

    Streckbein, Philipp; Reichert, Isabelle; Verhoff, Marcel A; Bödeker, Rolf-Hasso; Kähling, Christopher; Wilbrand, Jan-Falco; Schaaf, Heidrun; Howaldt, Hans-Peter; May, Andreas

    2014-12-01

    The increased number of adolescents and young adults with unknown or inaccurately given date of birth is a current issue in justice and legal medicine. The objective of this study was to determine the extent to which third molar calcification stages assessed on panoramic X-rays could be useful as additional criteria for forensic age estimation in living individuals, focusing on the legally important ages 17 and 18. In a retrospective multi-center study, the developmental stage of each individual's third molar was analyzed using Demirjian's scale in 2360 cases. Additionally, sex, age and ancestry were assessed. Individuals with the lowest calcification stage of all present molars in stage H were ≥18 years with a likelihood of ≥99.05% in the female (n=388), and ≥99.24% in the male (n=482) population. The lowest calcification stage of all present third molars proved to be useful as an additional reliable criterion for the determination of an age ≥18 years.

  1. 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

  2. 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

  3. 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.

  4. Middle-Aged More Often Diagnosed with Late-Stage Lung Cancer

    MedlinePlus

    ... Middle-Aged More Often Diagnosed With Late-Stage Lung Cancer British study highlights the need for better early detection, researchers say To use the sharing features on this page, please enable JavaScript. (*this news item will not ...

  5. Developmental Screening Using the Ages and Stages Questionnaire: Standardized versus Real-World Conditions

    ERIC Educational Resources Information Center

    San Antonio, Marianne C.; Fenick, Ada M.; Shabanova, Veronika; Leventhal, John M.; Weitzman, Carol C.

    2014-01-01

    Developmental screens are often used in nonstandardized conditions, such as pediatric waiting rooms, despite validation under standardized conditions. We examined the reproducibility of the Ages and Stages Questionnaire (ASQ), a developmental screening instrument commonly used in pediatric practices, under standardized versus nonstandardized…

  6. From stage to age in variable environments: life expectancy and survivorship.

    PubMed

    Tuljapurkar, Shripad; Horvitz, Carol C

    2006-06-01

    Stage-based demographic data are now available on many species of plants and some animals, and they often display temporal and spatial variability. We provide exact formulas to compute age-specific life expectancy and survivorship from stage-based data for three models of temporal variability: cycles, serially independent random variation, and a Markov chain. These models provide a comprehensive description of patterns of temporal variation. Our formulas describe the effects of cohort (birth) environmental condition on mortality at all ages, and of the effects on survivorship of environmental variability experienced over the course of life. This paper complements existing methods for time-invariant stage-based data, and adds to the information on population growth and dynamics available from stochastic demography. PMID:16869426

  7. From stage to age in variable environments: life expectancy and survivorship.

    PubMed

    Tuljapurkar, Shripad; Horvitz, Carol C

    2006-06-01

    Stage-based demographic data are now available on many species of plants and some animals, and they often display temporal and spatial variability. We provide exact formulas to compute age-specific life expectancy and survivorship from stage-based data for three models of temporal variability: cycles, serially independent random variation, and a Markov chain. These models provide a comprehensive description of patterns of temporal variation. Our formulas describe the effects of cohort (birth) environmental condition on mortality at all ages, and of the effects on survivorship of environmental variability experienced over the course of life. This paper complements existing methods for time-invariant stage-based data, and adds to the information on population growth and dynamics available from stochastic demography.

  8. 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.

  9. Dating age and stage as correlates of adolescent sexual attitudes and behavior.

    PubMed

    Miller, B C; Mccoy, J K; Olson, T D

    1986-01-01

    Dating experiences, especially the type or stage of dating, have consistently been found to be related to premarital sexual behavior. Findings regarding the age at 1st date and sexual behavior have been less consistent. This paper examined the age at which dating began and the type of dating relationship as correlates of premarital sexual attitudes and behavior among mid-teen adolescents. The analyses were based on a sample of high school students (n=836), most of whom were between the ages of 15 and 18 when the surveys were conducted. Early dating, especially early steady dating, was related to permissive attitudes and to premarital sexual experience among both males and females. The relationship between early dating and intercourse experience was particulary strong among Mormons, a religious group which has institutionalized age 16 as the legitimate age to begin dating. PMID:12341601

  10. 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

  11. 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

  12. 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

  13. 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.

  14. 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

  15. 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

  16. Transitions in Physiologic Coupling: Sleep Stage and Age Dependence of Cardio-respiratory Phase Synchronization

    NASA Astrophysics Data System (ADS)

    Bartsch, Ronny P.; Ivanov, Plamen Ch.

    2012-02-01

    Recent studies have focused on various features of cardiac and respiratory dynamics with the aim to better understand key aspects of the underlying neural control of these systems. We investigate how sleep influences cardio-respiratory coupling, and how the degree of this coupling changes with transitions across sleep stages in healthy young and elderly subjects. We analyze full night polysomnographic recordings of 189 healthy subjects (age range: 20 to 90 years). To probe cardio-respiratory coupling, we apply a novel phase synchronization analysis method to quantify the adjustment of rhythms between heartbeat and breathing signals. We investigate how cardio-respiratory synchronization changes with sleep-stage transitions and under healthy aging. We find a statistically significant difference in the degree of cardio-respiratory synchronization during different sleep stages for both young and elderly subjects and a significant decline of synchronization with age. This is a first evidence of how sleep regulation and aging influence a key nonlinear mechanism of physiologic coupling as quantified by the degree of phase synchronization between the cardiac and respiratory systems, which is of importance to develop adequate modeling approaches.

  17. Influence of age, breed, and stage of pregnancy on hepatic ultrasonographic findings in cows.

    PubMed

    Braun, U; Gerber, D

    1994-09-01

    Influence of age, breed, and stage of pregnancy on hepatic ultrasonographic findings of cows was determined. In addition, the relation between body weight, height at the withers, milk production, and the measurements determined via ultrasonography was investigated. The liver of 186 cows was examined ultrasonographically. The cows comprised Swiss Braunvieh, Simmental, and Holstein breeds, and age ranged from 2.5 to 11.5 years. The ultrasonographic findings of the liver, gallbladder, caudal vena cava, and portal vein were described, and the position, size, thickness, and distal angle of the liver were determined. In addition, the position and diameter of the caudal vena cava and portal vein were determined. There was no significant difference between any of the variables determined and breed or age. Therefore, measurements for the 3 breeds and for the various ages were summarized into 1 group. There were significant correlations between body weight, milk production, and size and thickness of the liver. In 3 pregnant cows, the liver was examined ultrasonographically 8 times during the course of pregnancy. Positive correlation was detected between stage of pregnancy and diameter of the caudal vena cava. There was a negative correlation between stage of pregnancy and diameter of the portal vein. In 23 cows, the ultrasonographically determined measurements of the liver were compared with those determined at slaughter. Weight of the liver correlated well to thickness of the liver determined via ultrasonography.

  18. 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.

  19. Enzyme replacement therapy for mucopolysaccharidosis VI: Growth and pubertal development in patients treated with recombinant human N-acetylgalactosamine 4-sulfatase

    PubMed Central

    Decker, Celeste; Yu, Zi-Fan; Giugliani, Roberto; Schwartz, Ida Vanessa D.; Guffon, Nathalie; Teles, Elisa Leão; Miranda, M. Clara Sá; Wraith, J. Edmond; Beck, Michael; Arash, Laila; Scarpa, Maurizio; Ketteridge, David; Hopwood, John J.; Plecko, Barbara; Steiner, Robert; Whitley, Chester B.; Kaplan, Paige; Swiedler, Stuart J.; Conrad, Susan; Harmatz, Paul

    2010-01-01

    Background and Methods Growth failure is characteristic of untreated mucopolysaccharidosis type VI (MPS VI: Maroteaux-Lamy syndrome). Growth was studied in fifty-six MPS VI patients (5 to 29 years old) prior to and for up to 240 weeks of weekly infusions of recombinant human arylsulfatase B (rhASB) at 1 mg/kg during Phase 1/2, Phase 2, Phase 3 or Phase 3 Extension clinical trials. Height, weight, and Tanner stage data were collected. Pooled data were analyzed to determine mean height increase by treatment week, growth impacts of pubertal status, baseline urinary GAG, and age at treatment initiation. Growth rate for approximately 2 years prior to and following treatment initiation was analyzed using longitudinal modeling. Results Mean height increased by 2.9 cm after 48 weeks and 4.3 cm after 96 weeks on enzyme replacement therapy (ERT). Growth on ERT was not correlated with baseline urinary GAG. Patients under 16 years of age showed greatest increases in height on treatment. Model results based on pooled data showed significant improvement in growth rate during 96 weeks of ERT when compared to the equivalent pretreatment time period. Delayed pubertal onset or progression was noted in 10 patients entering the clinical trials; all of whom showed progression of at least one Tanner stage during 2 years on ERT, and 6 of whom (60%) completed puberty. Conclusion Analysis of mean height by treatment week and longitudinal modeling demonstrate significant increase in height and growth rate in MPS VI patients receiving long-term ERT. This impact was greatest in patients aged below 16 years. Height increase may result from bone growth and/or reduction in joint contractures. Bone growth and resolution of delayed puberty may be related to improvements in general health, bone cell health, nutrition, endocrine gland function and reduced inflammation. PMID:20634905

  20. 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…

  1. 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…

  2. 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…

  3. 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

  4. Identification of morphological markers of sarcopenia at early stage of aging in skeletal muscle of mice.

    PubMed

    Sayed, Ramy K A; de Leonardis, Erika Chacin; Guerrero-Martínez, José A; Rahim, Ibtissem; Mokhtar, Doaa M; Saleh, Abdelmohaimen M; Abdalla, Kamal E H; Pozo, María J; Escames, Germaine; López, Luis C; Acuña-Castroviejo, Darío

    2016-10-01

    The gastrocnemius muscle (GM) of young (3months) and aged (12months) female wild-type C57/BL6 mice was examined by light and electron microscopy, looking for the presence of structural changes at early stage of the aging process. Morphometrical parameters including body and gastrocnemius weights, number and type of muscle fibers, cross section area (CSA), perimeter, and Feret's diameter of single muscle fiber, were measured. Moreover, lengths of the sarcomere, A-band, I-band, H-zone, and number and CSA of intermyofibrillar mitochondria (IFM), were also determined. The results provide evidence that 12month-old mice had significant changes on skeletal muscle structure, beginning with the reduction of gastrocnemius weight to body weight ratio, compatible with an early loss of skeletal muscle function and strength. Moreover, light microscopy revealed increased muscle fibers size, with a significant increase on their CSA, perimeter, and diameter of both type I and type II muscle fibers, and a reduction in the percentage of muscle area occupied by type II fibers. Enhanced connective tissue infiltrations, and the presence of centrally nucleated muscle fibers, were also found in aged mice. These changes may underlie an attempt to compensate the loss of muscle mass and muscle fibers number. Furthermore, electron microscopy discovered a significant age-dependent increase in the length of sarcomeres, I and H bands, and reduction on the overlapped actin/myosin length, supporting contractile force loss with age. Electron microscopy also showed an increased number and CSA of IFM with age, which may reveal more endurance at 12months of age. Together, mice at early stage of aging already show significant changes in gastrocnemius muscle morphology and ultrastructure that are suggestive of the onset of sarcopenia.

  5. Aging Effects on Cardiac and Respiratory Dynamics in Healthy Subjects across Sleep Stages

    PubMed Central

    Schumann, Aicko Y.; Bartsch, Ronny P.; Penzel, Thomas; Ivanov, Plamen Ch.; Kantelhardt, Jan W.

    2010-01-01

    Study Objectives: Respiratory and heart rate variability exhibit fractal scaling behavior on certain time scales. We studied the short-term and long-term correlation properties of heartbeat and breathing-interval data from disease-free subjects focusing on the age-dependent fractal organization. We also studied differences across sleep stages and night-time wake and investigated quasi-periodic variations associated with cardiac risk. Design: Full-night polysomnograms were recorded during 2 nights, including electrocardiogram and oronasal airflow. Setting: Data were collected in 7 laboratories in 5 European countries. Participants: 180 subjects without health complaints (85 males, 95 females) aged from 20 to 89 years. Interventions: None. Measurements and Results: Short-term correlations in heartbeat intervals measured by the detrended fluctuation analysis (DFA) exponent α1 show characteristic age dependence with a maximum around 50–60 years disregarding the dependence on sleep and wake states. Long-term correlations measured by α2 differ in NREM sleep when compared with REM sleep and wake, besides weak age dependence. Results for respiratory intervals are similar to those for α2 of heartbeat intervals. Deceleration capacity (DC) decreases with age; it is lower during REM and deep sleep (compared with light sleep and wake). Conclusion: The age dependence of α1 should be considered when using this value for diagnostic purposes in post-infarction patients. Pronounced long-term correlations (larger α2) for heartbeat and respiration during REM sleep and wake indicate an enhanced control of higher brain regions, which is absent during NREM sleep. Reduced DC possibly indicates an increased cardiovascular risk with aging and during REM and deep sleep. Citation: Schumann AY; Bartsch RP; Penzel T; Ivanov PC; Kantelhardt JW. Aging effects on cardiac and respiratory dynamics in healthy subjects across sleep stages. SLEEP 2010;33(7):943-955. PMID:20614854

  6. Identification of morphological markers of sarcopenia at early stage of aging in skeletal muscle of mice.

    PubMed

    Sayed, Ramy K A; de Leonardis, Erika Chacin; Guerrero-Martínez, José A; Rahim, Ibtissem; Mokhtar, Doaa M; Saleh, Abdelmohaimen M; Abdalla, Kamal E H; Pozo, María J; Escames, Germaine; López, Luis C; Acuña-Castroviejo, Darío

    2016-10-01

    The gastrocnemius muscle (GM) of young (3months) and aged (12months) female wild-type C57/BL6 mice was examined by light and electron microscopy, looking for the presence of structural changes at early stage of the aging process. Morphometrical parameters including body and gastrocnemius weights, number and type of muscle fibers, cross section area (CSA), perimeter, and Feret's diameter of single muscle fiber, were measured. Moreover, lengths of the sarcomere, A-band, I-band, H-zone, and number and CSA of intermyofibrillar mitochondria (IFM), were also determined. The results provide evidence that 12month-old mice had significant changes on skeletal muscle structure, beginning with the reduction of gastrocnemius weight to body weight ratio, compatible with an early loss of skeletal muscle function and strength. Moreover, light microscopy revealed increased muscle fibers size, with a significant increase on their CSA, perimeter, and diameter of both type I and type II muscle fibers, and a reduction in the percentage of muscle area occupied by type II fibers. Enhanced connective tissue infiltrations, and the presence of centrally nucleated muscle fibers, were also found in aged mice. These changes may underlie an attempt to compensate the loss of muscle mass and muscle fibers number. Furthermore, electron microscopy discovered a significant age-dependent increase in the length of sarcomeres, I and H bands, and reduction on the overlapped actin/myosin length, supporting contractile force loss with age. Electron microscopy also showed an increased number and CSA of IFM with age, which may reveal more endurance at 12months of age. Together, mice at early stage of aging already show significant changes in gastrocnemius muscle morphology and ultrastructure that are suggestive of the onset of sarcopenia. PMID:27435496

  7. The Benefit of Adjuvant Chemotherapy in Elderly Patients with Stage III Colorectal Cancer is Independent of Age and Comorbidity

    PubMed Central

    Wildes, Tanya M.; Kallogjeri, Dorina; Powers, Brian; Vlahiotis, Anna; Mutch, Matthew; Spitznagel, Edward L.; Tan, Benjamin; Piccirillo, Jay F.

    2010-01-01

    Objectives To determine the combined effect of age and comorbidity on receipt of chemotherapy and its impact on survival in elderly patients with stage III colorectal cancer (CRC). Materials and methods All patients over age 65 with Stage III CRC diagnosed 1996–2006 were identified from the Barnes-Jewish Hospital Oncology Data Services registry. An age/comorbidity staging system was created using the ACE-27 comorbidity index and data from both Stage II and III CRC. The staging system was then applied to patients with Stage III CRC. Odds of receiving chemotherapy were calculated, and survival analyses determined the impact of chemotherapy on overall survival in each age/comorbidity stage. Results 435 patients with Stage III CRC were evaluated [median age 75 years (range 65–99)]. Advancing age/comorbidity stage (Alpha, Beta, Gamma) was associated with decreasing odds of receiving chemotherapy for Stage III CRC [Odds Ratio 0.83 (95% CI, 0.51–1.35) for Beta and 0.14 (95% CI, 0.08–0.24) for Gamma, compared to Alpha]. Chemotherapy was associated with lower risk of death in each of the age/comorbidity stages, compared to those who underwent surgery only. The hazard ratio for death in patients who did not receive chemotherapy, relative to those who did, within each age/comorbidity stage was 1.8 [95%CI 1.06–3.06] for Alpha, 2.24 [95%CI 1.38–3.63] for Beta and 2.10 [95% CI 1.23–3.57] for Gamma. Conclusion While stage III CRC patients with increasing age and comorbidity are less likely to receive chemotherapy, receipt of chemotherapy is associated with a lower risk of death. PMID:21113435

  8. Microstructural evolution of 7012 alloy during the early stages of artificial ageing

    SciTech Connect

    Ferragut, R.; Somoza, A.; Tolley, A.

    1999-11-26

    A study of the microstructural evolution of a commercial 7012 (Al-Zn-Mg-Cu) age-hardenable alloy following artificial ageing by high resolution and conventional transmission electron microscopy and positron annihilation lifetime spectroscopy is presented. At the early stages of decomposition, the microstructure included precipitation of either pre-precipitate solute clusters or Guinier-Preston zones and semi-coherent {eta}{prime} precipitates, with typical sizes between 1 and 10 nm. Quantitative information on the size, number density and morphology of the particles present in the microstructure was obtained. The results were correlated with those obtained using positron annihilation lifetime spectroscopy.

  9. 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…

  10. 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,…

  11. 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…

  12. 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)

  13. Aging assessment and license renewals: Plant life management for the first stage boiling water reactor

    SciTech Connect

    Tezuka, Kenichi; Kawamura, Shinichi; Aoki, Masataka; Mori, Tsuguo

    1996-09-01

    The first stage Boiling Water Reactors (BWRs) have been operating more than 25 years. Some components have potential of failure by aging. So, evaluations have been done for the main components such as Reactor Pressure Vessel (RPV), Reactor Internals, Primary Coolant Piping, Reactor Recirculation Pump, Cable (Inside PCV), Primary Containment Vessel (PCV) and Concrete Structure. This evaluation has been done by joint study between electric utilities and manufacturers to confirm integrity and identify necessary development.

  14. 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

  15. Human dental age estimation using third molar developmental stages: Accuracy of age predictions not using country specific information.

    PubMed

    Thevissen, P W; Alqerban, A; Asaumi, J; Kahveci, F; Kaur, J; Kim, Y K; Pittayapat, P; Van Vlierberghe, M; Zhang, Y; Fieuws, S; Willems, G

    2010-09-10

    Unquestionable forensic age investigations are based on statistical models constructed on a sample containing subjects of identical origin as the examined individual. In cases where corresponding models are unavailable, the established report has to describe the possible effects of this unrelated information on the predicted age outcome. The aim of this study is to collect country specific databases of third molar development and to verify how the related dental age estimations are influenced if we were to use dental developmental information only from Belgium or from all collected countries together. Data containing third molar developmental stages scored following Gleiser and Hunt (modified by Köhler) were collected from 9 country specific populations (Belgium, China, Japan, Korea, Poland, Thailand, Turkey, Saudi-Arabia and South-India). Age predictions were obtained from a training dataset and validated on a test dataset. Bayes rule using the repeated third molar scores is applied to get age predictions and prediction intervals. Three age predictions were compared for males and females separately. For the first prediction, the training dataset contains only Belgian subjects. For the second prediction, the training dataset for each country consists only of subjects of the country itself. For the final prediction, subjects from all countries are pooled into one common training dataset. Besides the (absolute) difference between the chronological age and the predicted age, specific interest lies in the juvenile-adult distinction. In the age range from 16 to 22 years 6982 subjects (3189 male and 3793 female) were analyzed. Using information on third molar development from Belgium compared to information from the country specific databases hardly increased the mean absolute differences (MAD) and mean squared errors (MSE): the MAD and MSE increased on average with 0.5 and 2.5 months with maximal increases of, respectively 1.6 and 7.3 months. Using information from all

  16. Human dental age estimation using third molar developmental stages: Accuracy of age predictions not using country specific information.

    PubMed

    Thevissen, P W; Alqerban, A; Asaumi, J; Kahveci, F; Kaur, J; Kim, Y K; Pittayapat, P; Van Vlierberghe, M; Zhang, Y; Fieuws, S; Willems, G

    2010-09-10

    Unquestionable forensic age investigations are based on statistical models constructed on a sample containing subjects of identical origin as the examined individual. In cases where corresponding models are unavailable, the established report has to describe the possible effects of this unrelated information on the predicted age outcome. The aim of this study is to collect country specific databases of third molar development and to verify how the related dental age estimations are influenced if we were to use dental developmental information only from Belgium or from all collected countries together. Data containing third molar developmental stages scored following Gleiser and Hunt (modified by Köhler) were collected from 9 country specific populations (Belgium, China, Japan, Korea, Poland, Thailand, Turkey, Saudi-Arabia and South-India). Age predictions were obtained from a training dataset and validated on a test dataset. Bayes rule using the repeated third molar scores is applied to get age predictions and prediction intervals. Three age predictions were compared for males and females separately. For the first prediction, the training dataset contains only Belgian subjects. For the second prediction, the training dataset for each country consists only of subjects of the country itself. For the final prediction, subjects from all countries are pooled into one common training dataset. Besides the (absolute) difference between the chronological age and the predicted age, specific interest lies in the juvenile-adult distinction. In the age range from 16 to 22 years 6982 subjects (3189 male and 3793 female) were analyzed. Using information on third molar development from Belgium compared to information from the country specific databases hardly increased the mean absolute differences (MAD) and mean squared errors (MSE): the MAD and MSE increased on average with 0.5 and 2.5 months with maximal increases of, respectively 1.6 and 7.3 months. Using information from all

  17. Age estimation by dental developmental stages in children and adolescents in Iceland.

    PubMed

    Vidisdottir, Sigridur Rosa; Richter, Svend

    2015-12-01

    Studies have shown that it is necessary to create a database for dental maturity for every population and compare it to others. The present study is the first one for dental development in the Icelandic population the age range being 4-24 years. It will help in forensic dental age estimation and will also help dentists, physicians, anthropologists, archaeologists and other professionals who rely on developmental age assessment in children and adolescents. In this present retrospective cross-sectional study, dental maturity was determined in 1100 Icelandic children and adolescents from orthopantomograms (OPGs). The first 100 were used for a pilot study and the remaining 1000 for the main study. A total of 23 subjects were excluded. The sample consisted of 508 girls and 469 boys from the age of 4-24 years and a dental developmental scoring system was used as a standard for determination of dental maturity stages. A total of 200 OPGs were studied both on the left and right side and the remaining on the right side. Dental maturity was established for all teeth and both genders, when the sample permitted, from the beginning of crown formation to the root apex closure. The Cronbach's Alpha reliability test showed high reliability, R=0.982. Girls in Iceland reach dental maturity root completed (stage 10, Rc) at 17.81 years of age for the maxillary and at 18.47 years for the mandibular teeth. Boys reach dental maturity root completed (stage 10, Rc) at 18.00 years of age in the maxilla and 17.63 in the mandible. There was no significant difference between left and right side (r=0.95-1.00) and there was no gender difference, except in root formation in maxillary and mandibular canines where girls reached root completed earlier than boys. A reliable database has been established in Iceland for tooth development in the age range of 4-24 years, which is compatible with international studies. These results will help forensic odontologists and other professionals to estimate with

  18. Understanding age-related reductions in visual working memory capacity: Examining the stages of change detection

    PubMed Central

    Duda, Bryant; Hussey, Erin; Mason, Emily; Molitor, Robert J.; Woodman, Geoffrey F.; Ally, Brandon A.

    2014-01-01

    Visual working memory (VWM) capacity is reduced in older adults. Research has shown age-related impairments to VWM encoding, but aging is likely to affect multiple stages of VWM. In the present study, we recorded the event-related potentials (ERPs) of younger and older adults during VWM maintenance and retrieval. We measured encoding-stage processing with the P1 component, maintenance-stage processing with the contralateral delay activity (CDA), and retrieval-stage processing by comparing the activity for old and new items (old–new effect). Older adults showed lower behavioral capacity estimates (K) than did younger adults, but surprisingly, their P1 components and CDAs were comparable to those of younger adults. This remarkable dissociation between neural activity and behavior in the older adults indicated that the P1 and CDA did not accurately assess their VWM capacity. However, the neural activity evoked during VWM retrieval yielded results that helped clarify the age-related differences. During retrieval, younger adults showed early old–new effects in frontal and occipital areas and a late central–parietal old–new effect, whereas older adults showed a late right-lateralized parietal old–new effect. The younger adults’ early old–new effects strongly resembled an index of perceptual fluency, suggesting that perceptual implicit memory was activated. The activation of implicit memory could have facilitated the younger adults’ behavior, and the lack of these early effects in older adults may suggest that they have much lower-resolution memory than do younger adults. From these data, we speculated that younger and older adults store the same number of items in VWM, but that younger adults store a higher-resolution representation than do older adults. PMID:24420648

  19. A behavioral stages model of classical (Pavlovian) conditioning: application to cognitive aging.

    PubMed

    Powell, D A

    1999-01-01

    In the present article, it is argued that a five-stage sequential model of the behavioral and neurophysiological events that occur when organisms are exposed to signals predicting significant events suggests that classical conditioning produces multiple memory traces involving both excitatory and inhibitory processes. Further, these multiple brain structures and associated neurophysiological mechanisms are beginning to be understood; thus, using Pavlovian conditioning techniques to study aging and cognitive functions may provide insights into which brain structures or mechanisms are responsible for more general age-related declines in associative learning and memory. The evidence for this model is briefly reviewed and studies suggesting age-related effects on classical conditioning of various response systems are described within the context of the brain structures implicated by the model.

  20. [Research of Embryonic Mortality Stages of Drosophila melanogaster Depending on Age and Starvation of an Imago].

    PubMed

    Kostenko, V V; Kolot, N V; Vorobyova, L I

    2015-01-01

    Influence of age of parents and duration of starvation on egg production and demonstration of embryonic mortality at different stages of egg development has been studied. It is shown that, with increasing age of organisms, the overall egg production reduces and the percentage of embryonic mortality increases at 0-5.5 and 5.5-17 h of development. An increase in the duration of starvation also promotes a reduction in egg production in 3- and 10-day-old adult D. melanogaster compared with short-term starvation. A statistically significant effect of factors, such as the allelic state of the white locus, the genetic background, the age of the parents, and the duration of starvation, on all studied parameters was established.

  1. 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

  2. Age and petrology of alkalic postshield and rejuvenated-stage lava from Kauai, Hawaii

    USGS Publications Warehouse

    Clague, D.A.; Dalrymple, G.B.

    1988-01-01

    At the top of the Waimea Canyon Basalt on the island of Kauai, rare flows of alkalic postshield-stage hawaiite and mugearite overlie tholeiitic flows of the shield stage. These postshield-stage flows are 3.92 Ma and provide a younger limit for the age of the tholeiitic shield stage. The younger Koloa Volcanics consist of widespread alkalic rejuvenated-stage flows and vents of alkalic basalt, basanite, nephelinite, and nepheline melilitite that erupted between 3.65 and 0.52 Ma. All the flows older than 1.7 Ma occur in the west-northwestern half of the island and all the flows younger than 1.5 Ma occur in the east-southeastern half. The lithologies have no spatial or chronological pattern. The flows of the Koloa Volcanics are near-primary magmas generated by variable small degrees of partial melting of a compositionally heterogeneous garnet-bearing source that has about two-thirds the concentration of P2O5, rare-earth elements, and Sr of the source of the Honolulu Volcanics on the island of Oahu. The same lithology in the Koloa and Honolulu Volcanics is generated by similar degrees of partial melting of distinct source compositions. The lavas of the Koloa Volcanics can be generated by as little as 3 percent to as much as 17 percent partial melting for nepheline melilitite through alkalic basalt, respectively. Phases that remain in the residue of the Honolulu Volcanics, such as rutile and phlogopite, are exhausted during formation of the Koloa Volcanics at all but the smallest degrees of partial melting. The mantle source for Kauai lava becomes systematically more depleted in 87Sr/86Sr as the volcano evolves from the tholeiitic shield stage to the alkalic postshield stage to the alkalic rejuvenated stage: at the same time, the lavas become systematically more enriched in incompatible trace elements. On a shorter timescale, the lavas of the Koloa Volcanics display the same compositional trends, but at a lower rate of change. The source characteristics of the Koloa

  3. Decreased growth rate of P. falciparum blood stage parasitemia with age in a holoendemic population.

    PubMed

    Pinkevych, Mykola; Petravic, Janka; Chelimo, Kiprotich; Vulule, John; Kazura, James W; Moormann, Ann M; Davenport, Miles P

    2014-04-01

    In malaria holoendemic settings, decreased parasitemia and clinical disease is associated with age and cumulative exposure. The relative contribution of acquired immunity against various stages of the parasite life cycle is not well understood. In particular, it is not known whether changes in infection dynamics can be best explained by decreasing rates of infection, or by decreased growth rates of parasites in blood. Here, we analyze the dynamics of Plasmodium falciparum infection after treatment in a cohort of 197 healthy study participants of different ages. We use both polymerase chain reaction (PCR) and microscopy detection of parasitemia in order to understand parasite growth rates and infection rates over time. The more sensitive PCR assay detects parasites earlier than microscopy, and demonstrates a higher overall prevalence of infection than microscopy alone. The delay between PCR and microscopy detection is significantly longer in adults compared with children, consistent with slower parasite growth with age. We estimated the parasite multiplication rate from delay to PCR and microscopy detections of parasitemia. We find that both the delay between PCR and microscopy infection as well as the differing reinfection dynamics in different age groups are best explained by a slowing of parasite growth with age.

  4. Dental age estimation from the developmental stage of the third molars in Iranian population.

    PubMed

    Rai, Balwant; Kaur, Jasdeep; Jafarzadeh, Hamid

    2010-08-01

    A sharp increase in forensic age estimation of living persons has been observed in recent years. However, ethnic populations residing in different countries have been insufficiently analyzed. The aim of this study was to achieve a referral database and regression equations for dental age estimation of unaccompanied minors of Iran nationality. A total of 1200 orthopantomograms were collected from original Iran and equally divided in age categories between 10 and 27 years. On the radiographs, the developmental stage of the third molars was scored applying a Demirjian et al. scoring technique. Inter- and intra-observer reliabilities were tested using kappa statistics. Correlation between the scores of all four wisdom maxillary and mandibular third molars teeth and left/right symmetry were evaluated with spearman correlation coefficient. Student's t-test on asymmetry was performed and regression formulas were calculated. The present database was the first to assemble third molar developmental scores on radiographs of Iran individuals and provided more appropriate dental age estimation of unaccompanied Iran minors. To enhance the accuracy of forensic age estimates based on third molars mineralization, the use of population-specific standards is recommended.

  5. Variation in honey bee gut microbial diversity affected by ontogenetic stage, age and geographic location.

    PubMed

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler, Martin; Titera, Dalibor; Hakl, Josef; Mrazek, Jakub; Bunesova, Vera; Rada, Vojtech

    2015-01-01

    Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting. Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees. Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage. The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may

  6. Variation in Honey Bee Gut Microbial Diversity Affected by Ontogenetic Stage, Age and Geographic Location

    PubMed Central

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler, Martin; Titera, Dalibor; Hakl, Josef; Mrazek, Jakub; Bunesova, Vera; Rada, Vojtech

    2015-01-01

    Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting. Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees. Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage. The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may

  7. Variation in honey bee gut microbial diversity affected by ontogenetic stage, age and geographic location.

    PubMed

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler, Martin; Titera, Dalibor; Hakl, Josef; Mrazek, Jakub; Bunesova, Vera; Rada, Vojtech

    2015-01-01

    Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting. Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees. Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage. The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may

  8. A school-curriculum-based exercise intervention program for two years in pre-pubertal girls does not influence hip structure

    PubMed Central

    Alwis, Gayani; Linden, Christian; Stenevi-Lundgren, Susanna; Ahlborg, Henrik G; Dencker, Magnus; Besjakov, Jack; Gardsell, Per; Karlsson, Magnus K

    2008-01-01

    Background It is known that physical activity during growth has a positive influence on bone mineral accrual, and is thus possibly one strategy to prevent osteoporosis. However, as bone geometry, independent of areal bone mineral density (aBMD), influences fracture risk, this study aimed to evaluate whether hip structure in pre-pubertal girls is also affected by a two-year exercise intervention program. Methods Forty-two girls aged 7–9 years in a school-curriculum-based exercise intervention program comprising 40 minutes of general physical activity per school day (200 minutes per week) were compared with 43 age-matched girls who participated in the general Swedish physical education curriculum comprising a mean of 60 minutes per week. The hip was scanned by dual energy X-ray absorptiometry (DXA) and the hip structural analysis (HSA) software was applied to evaluate bone mineral content (BMC, g), areal bone mineral density (aBMD, g/cm2), periosteal diameter, cross-sectional area (CSA, cm2), section modulus (Z, cm3) and cross-sectional moment of inertia (CSMI, cm4) of the femoral neck (FN). Annual changes were compared. Subjective duration of physical activity was estimated by questionnaire and objective level of everyday physical activity at follow-up by means of accelerometers worn for four consecutive days. All children remained at Tanner stage 1 throughout the study. Group comparisons were made by independent student's t-test between means and analyses of covariance (ANCOVA). Results At baseline, the two groups did not differ with regard to age, anthropometrics or bone parameters. No between-group differences were observed for annual changes in the FN variables measured. Conclusion A two-year school-based moderately intense general exercise program for 7–9-year-old pre-pubertal girls does not influence structural changes in the FN. PMID:18442381

  9. 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.

  10. 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

  11. 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.

  12. 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

  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. Influences of competition level, gender, player nationality, career stage and playing position on relative age effects.

    PubMed

    Schorer, J; Cobley, S; Büsch, D; Bräutigam, H; Baker, J

    2009-10-01

    Relative age, referring to the chronological age differences between individuals within annually age-grouped cohorts, is regarded as influential to an athlete's development, constraining athletic skill acquisition. While many studies have suggested different mechanisms for this effect, they have typically examined varying sports, precluding an examination of the possible inter-play between factors. Our three studies try to bridge this gap by investigating several moderators for relative age effects (RAEs) in one sport. Handball is a sport with position-specific demands, high cultural relevance and a performance context with established developmental structures and levels of representation for males and females. In Study 1, we investigated the influence of competition level and gender on RAEs before adulthood. In Study 2, elite participation, player nationality and stage of career are considered during adulthood. In Study 3, playing position and laterality (i.e., right vs left handedness) are investigated as moderators. Collectively, the results emphasize the complex inter-play of direct and indirect influences on RAEs in sports, providing evidence toward explaining how RAEs influence the development and maintenance of expertise.

  15. 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

  16. Age and the Association of Kidney Measures with Mortality and End-Stage Renal Disease

    PubMed Central

    Hallan, Stein I.; Matsushita, Kunihiro; Sang, Yingying; Mahmoodi, Bakhtawar K.; Black, Corri; Ishani, Areef; Kleefstra, Nanne; Naimark, David; Roderick, Paul; Tonelli, Marcello; Wetzels, Jack F.M.; Astor, Brad C.; Gansevoort, Ron T.; Levin, Adeera; Wen, Chi-Pang; Coresh, Josef

    2014-01-01

    Context Chronic kidney disease (CKD) is prevalent in older individuals, but the risk implications of low estimated glomerular filtration rate (eGFR) and high albuminuria across the full age range are controversial. Objective To evaluate possible effect modification (interaction) of age on the association of estimated GFR and albuminuria with clinical risk examining both relative and absolute risk. Design, Setting, Participants We investigated 2,051,244 participants from 33 general population or high-risk (of vascular disease) cohorts and 13 CKD cohorts from Asia, Australesia, Europe, and North/South America conducted during 1972–2011 with mean follow-up time of 5.8 years (range 0–31 years). Main Outcome Measures Hazard ratios (HRs) of mortality and end-stage renal disease (ESRD) according to eGFR and albuminuria were meta-analyzed across age categories after adjusting for sex, race, cardiovascular disease, diabetes, systolic blood pressure, cholestserol, body mass index, and smoking. Absolute risks were estimated using HRs and average incidence rates. Results Mortality (112,325 deaths) and ESRD (8,411 events) risk were higher at lower eGFR and higher albuminuria in every age category. In general/high-risk cohorts, relative mortality risk for reduced eGFR decreased with increasing age: e.g., adjusted HRs (95% CI) at eGFR 45 vs. 80 ml/min/1.73m2 were 3.50 (2.55–4.81), 2.21 (2.02–2.41), 1.59 (1.42–1.77), and 1.35 (1.23–1.48) in age categories 18–54, 55–64, 65–74 and 75+ years, respectively (P-values for age interaction <0.05). Absolute risk differences for the same comparisons were higher at older age (9.0 [95% CI, 6.0–12.8], 12.2 [10.3–14.3], 13.3 [9.0–18.6], and 27.2 [13.5–45.5] excess deaths per 1,000 person-years, respectively). For increased albuminuria, reduction of relative risk with increasing age were less evident, while differences in absolute risk were higher in the older age categories (7.5 [95% CI, 4.3–11.9], 12.2 [7.9–17

  17. Genetics of Unilateral and Bilateral Age-Related Macular Degeneration Severity Stages

    PubMed Central

    Schick, Tina; Altay, Lebriz; Viehweger, Eva; Hoyng, Carel B.; den Hollander, Anneke I.; Felsch, Moritz; Fauser, Sascha

    2016-01-01

    Background Age-related macular degeneration (AMD) is a common disease causing visual impairment and blindness. Various gene variants are strongly associated with late stage AMD, but little is known about the genetics of early forms of the disease. This study evaluated associations of genetic factors and different AMD stages depending on unilateral and bilateral disease severity. Methods In this case-control study, participants were assigned to nine AMD severity stages based on the characteristics of each eye. 18 single nucleotide polymorphisms (SNPs) were genotyped and attempted to correlate with AMD severity stages by uni- and multivariate logistic regression analyses and trend analyses. Area under the receiver operating characteristic curves (AUC) were calculated. Results Of 3444 individuals 1673 were controls, 379 had early AMD, 333 had intermediate AMD and 989 showed late AMD stages. With increasing severity of disease and bilateralism more SNPs with significant associations were found. Odds ratios, especially for the main risk polymorphisms in ARMS2 (rs10490924) and CFH (rs1061170), gained with increasing disease severity and bilateralism (exemplarily: rs1061170: unilateral early AMD: OR = 1.18; bilateral early AMD: OR = 1.20; unilateral intermediate AMD: OR = 1.28; bilateral intermediate AMD: OR = 1.39, unilateral geographic atrophy (GA): OR = 1.50; bilateral GA: OR = 1.71). Trend analyses showed p<0.0001 for ARMS2 (rs10490924) and for CFH (rs1061170), respectively. AUC of risk models for various AMD severity stages was lowest for unilateral early AMD (AUC = 0.629) and showed higher values in more severely and bilaterally affected individuals being highest for late AMD with GA in one eye and neovascular AMD in the other eye (AUC = 0.957). Conclusion The association of known genetic risk factors with AMD became stronger with increasing disease severity, which also led to an increasing discriminative ability of AMD cases and controls. Genetic predisposition was

  18. Atomic structure of Cu-10. 9 at % Be alloys in the early stages of aging

    SciTech Connect

    Koo, Y.M.

    1987-01-01

    Diffuse x-ray scattering was employed to investigate the local atomic structure and static strains in a single crystal of a Cu-10.9 at. % Be alloy in the early stages of aging. In addition to these experiments, neutron elastic and inelastic scattering were obtained to investigate the phonon properties in the as-quenched state of this alloy. In the as-quenched state, there is a nearly regular array of small ellipsoidal Be clusters aligned along <100> directions (This produces the tweed contrast seen in TEM). The density of these clusters is 7.5 x 10/sup 26//m/sup 3/. The diffuse streaks seen in electron diffraction patterns are due largely to thermal diffuse scattering. Phonon-dispersion curves show no large differences from those of pure copper, except at (xi xi xi)/sub T/ zone boundary, where there is softening. This difference may be due to a Kohn anomaly. The elastic anisotropy of this alloy increases considerably with alloying, which probably leads to the plate-like GP zone morphology in subsequent aging treatments. The structure of the GP zones is a mixture of Be-rich single- and multi-layered zones. As aging proceeds, the zones grow in thickness.

  19. The Living Stage Improvisational Theatre Demonstration Project for Orthopedically Handicapped Children, Ages 4-8. Overview, 1978-1981.

    ERIC Educational Resources Information Center

    Alexander, Robert; Haynes, Wendy

    The Living Stage Improvisational Theatre Demonstration Project (Washington, D.C.) conducts weekly workshops to enhance the creative expression and self esteem of orthopedically handicapped children, aged 4 to 8 years. The Living Stage program is designed to demonstrate that methods of improvisational theatre can have a positive impact on parental…

  20. Age and stage dependency of estrogen receptor expression by lymphocyte precursors

    PubMed Central

    Igarashi, Hideya; Kouro, Taku; Yokota, Takafumi; Comp, Phillip C.; Kincade, Paul W.

    2001-01-01

    Sex steroids negatively regulate B lymphopoiesis in adult mice. Paradoxically, lymphocytes arise during fetal life, when estrogen levels are high and maternal lymphopoiesis is suppressed. Here we demonstrate that embryonic B lymphopoiesis was unaffected by estrogen, but sensitive to glucocorticoids. Both fetal and adult precursors contained glucocorticoid receptor transcripts, but only adult precursors expressed estrogen receptor α and β together with the androgen receptor. Fetal hematopoietic cells did not efficiently acquire functional estrogen receptors after transplantation to irradiated adult mice. Sex steroid receptors were also expressed in a stage- and developmental age-dependent fashion in human precursors. A developmental switch in responsiveness of hematopoietic cells to sex steroids may be essential for formation of the immune system. PMID:11752459

  1. Effect of age, sex and physiological stages on hematological indices of Banni buffalo (Bubalus bubalis)

    PubMed Central

    Patel, Mehul D.; Lateef, Abdul; Das, Hemen; Patel, Ajay S.; Patel, Ajay G.; Joshi, Axay B.

    2016-01-01

    Aim: To determine the physiological baseline values for hematological indices of Banni buffalo (Bubalus bubalis) as well as to assess their alteration due to age, sex and physiological stages. Materials and Methods: A total of 42 clinically healthy Banni buffaloes were categorized into seven groups (n=6): Group I (male calves ≤1 year), Group II (bulls >1 year), Group III (female calves ≤1 year), Group IV (pregnant lactating buffaloes), Group V (non-pregnant lactating buffaloes), Group VI (pregnant dry buffaloes), and Group VII (non-pregnant dry buffaloes). Blood samples collected aseptically from all the experimental groups were analyzed employing automated hematology analyzer. The data obtained were statistically analyzed; the mean and standard deviations were calculated and set as the reference values. Results: The erythrocytic indices viz. total erythrocytes count (TEC), hemoglobin, and packed cell volume (PCV) were significantly higher in bulls as compared to that of male calves unlike mean corpuscular volume, mean corpuscular hemoglobin (MCH), and MCH concentration. The female calves had higher TEC and PCV than the adult buffaloes irrespective of sex. The total leukocyte count (TLC) and neutrophil counts in male calves were significantly lower than the bulls unlike the eosinophil, while monocyte and basophil remained unchanged with age. The TLC, differential leukocyte count and platelet count varied non-significantly among the adult female groups at different physiological stages. However, neutrophils were found to be apparently higher in lactating buffaloes. Conclusion: The present study would be helpful for physiological characterization of this unique buffalo breed of Gujarat. Further, data generated may be a tool for monitoring the health and prognosis as well as diagnosis of diseases. PMID:27051182

  2. 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

  3. 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.

  4. Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

    PubMed Central

    Kristofco, Lauren A.; Cruz, Luis Colon; Haddad, Samuel P.; Behra, Martine L; Chambliss, C. Kevin; Brooks, Bryan W.

    2016-01-01

    Because basic toxicological data is unavailable for the majority of industrial compounds, High Throughput Screening (HTS) assays using the embryonic and larval zebrafish provide promising approaches to define bioactivity profiles and identify potential adverse outcome pathways for previously understudied chemicals. Unfortunately, standardized approaches, including HTS experimental designs, for examining fish behavioral responses to contaminants are rarely available. In the present study, we examined movement behavior of larval zebrafish over 7 days (4–10 days post fertilization or dpf) during typical daylight workday hours to determine whether intrinsic activity differed with age and time of day. We then employed an early life stage approach using the Fish Embryo Test (FET) at multiple developmental ages to evaluate whether photomotor response (PMR) behavior differed with zebrafish age following exposure to diazinon (DZN), a well-studied orthophosphate insecticide, and diphenhydramine (DPH), an antihistamine that also targets serotonin reuptake transporters and the acetylcholine receptor. 72 h studies were conducted at 1–4, 4–7 and 7–10 dpf, followed by behavioral observations using a ViewPoint system at 4, 7 and 10 dpf. Distance traveled and swimming speeds were quantified; nominal treatment levels were analytically verified by isotope-dilution LC-MSMS. Larval zebrafish locomotion displayed significantly different (p < 0.05) activity profiles over the course of typical daylight and workday hours, and these time of day PMR activity profiles were similar across ages examined (4–10 dpf). 10 dpf zebrafish larvae were consistently more sensitive to DPH than either the 4 or 7 dpf larvae with an environmentally realistic lowest observed effect concentration of 200 ng/L. Though ELS and FET studies with zebrafish typically focus on mortality or teratogenicity in 0–4 dpf organisms, behavioral responses of slightly older fish were several orders of magnitude more

  5. Association of Insurance Status and Age With Cervical Cancer Stage at Diagnosis: National Cancer Database, 2000–2007

    PubMed Central

    Cokkinides, Vilma; Virgo, Katherine S.; Bandi, Priti; Saslow, Debbie; Ward, Elizabeth M.

    2012-01-01

    Objectives. We examined the relationship of age at diagnosis and insurance status with stage among cervical cancer patients aged 21 to 85 years. Methods. We selected data on women (n = 69 739) diagnosed with invasive cervical cancer between 2000 and 2007 from the National Cancer Database. We evaluated the association between late stage (stage III/IV) and both insurance and age, with adjustment for race/ethnicity and other sociodemographic and clinical factors. We used multivariable log binomial models to estimate risk ratios (RRs) and 95% confidence intervals (CIs). Results. The proportion of late-stage disease increased with age: from 16.53% (21–34 years) to 42.44% (≥ 70 years). The adjusted relative risk of advanced-stage disease among women aged 50 years and older was 2.2 to 2.5 times that of patients aged 21 to 34 years. Uninsured (RR = 1.44; 95% CI = 1.40, 1.49), Medicaid (RR = 1.37, 95% CI = 1.34, 1.41), younger Medicare (RR = 1.12, 95% CI = 1.06, 1.19), and older Medicare (RR = 1.20, 95% CI = 1.15, 1.26) patients had a higher risk of late-stage disease than did privately insured patients. Conclusions. Screening should be encouraged for women at high risk for advanced-stage disease. PMID:22742058

  6. Mandibular third molar development staging to chronologic age and sex in north Indian children and young adults.

    PubMed

    Rai, B; Kaur, J; Anand, S C

    2009-12-01

    Age estimation is not only important for clinical but also for medico-legal purposes. The present study is an attempt to estimate the chronologic age based on the stages of third molar development following the eight stages (A-H) method of Demirjian et al8 and to compare third molar development by sex and age. We examined 250 orthopantomograms of young north Indian subjects of known chronologic age (range, 7-26 years). Statistical analysis was performed using the Mann-Whitney U-test and the Wilcoxon test between sex and age. Regression analysis was performed to obtain BR regression formulae for dental age calculation with the chronologic age. Statistically significant differences in mandibular third-molar development between males and females were revealed regarding the calcification stages D and G. The results further indicated that third-molar formation was attained earlier in females than in males. Statistical analysis showed a strong correlation between age and third-molar development for both the sexes.

  7. 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

  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. 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.

  10. Age-dependent postdiapause development in the gypsy moth (Lepidoptera: Lymantriidae) life stage model.

    PubMed

    Gray, David R

    2009-02-01

    For the last approximately 10 yr, the Gypsy Moth Life Stage (GLS) model has been used by pest managers to predict when important events in the gypsy moth, Lymantria dispar L., life cycle will occur (e.g., peak second larval instar population and male moth flight). Although the GLS model has been shown to outperform other gypsy moth phenology models, its predictions have not always been as accurate as desired. Differences between predicted and observed egg hatch phenology prompted a re-examination of the original experimental data that were used in the construction of the egg hatch submodels of the original GLS model, and a data processing error was discovered to have truncated the postdiapause experimental data. Analysis of the complete data set confirmed that developmental rates in the postdiapause phase were age and temperature dependent but that the developmental response to temperature is distinctly nonlinear at postdiapause initiation, in contrast to the indeterminate response previously reported. By incorporating the new estimates of developmental rate patterns and parameters into the GLS model, errors in the GLS-simulated egg hatch period were reduced by 33-71% and error in date of 50% cumulative egg hatch by 25-100%.

  11. Static Strain Aging Behavior of a Manganese-Silicon Steel After Single and Multi-stage Straining

    NASA Astrophysics Data System (ADS)

    Seraj, P.; Serajzadeh, S.

    2016-03-01

    In this work, static strain aging behavior of an alloy steel containing high amounts of silicon and manganese was examined while the influences of initial microstructure and pre-strain on the aging kinetics were evaluated as well. The rate of strain aging in a low carbon steel was also determined and compared with that occurred in the alloy steel. The rates of static strain aging in the steels were defined at room temperature and at 95 °C by means of double-hit tensile testing and hardness measurements. In addition, three-stage aging experiments at 80 °C were carried out to estimate aging behavior under multi-pass deformation processing. The results showed that in-solution manganese and silicon atoms could significantly affect the aging behavior of the steel and reduce the kinetics of static strain aging as compared to the low carbon steel. The initial microstructure also played an important role on the aging behavior. The rapidly cooled steel having mean ferrite grain size of 9.7 μm showed the least aging susceptibility index during the aging experiments. Accordingly, the activation energies for static strain aging were calculated as 93.2 and 85.7 kJ/mole for the alloy steel having fine and coarse ferrite-pearlite structures, respectively while it was computed as 79.1 kJ/mole for the low carbon steel with ferrite mean grain size of about 16.2 μm.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. Testosterone related to age and life-history stages in male baboons and geladas

    PubMed Central

    Beehner, Jacinta C.; Gesquiere, Laurence; Seyfarth, Robert M.; Cheney, Dorothy L.; Alberts, Susan C.; Altmann, Jeanne

    2013-01-01

    Despite significant advances in our knowledge of how testosterone mediates life-history trade-offs, this research has primarily focused on seasonal species. We know comparatively little about the relationship between testosterone and life-history stages for non-seasonally breeding species. Here we examine testosterone profiles across the lifespan of males from three non-seasonally breeding primates: yellow baboons (Papio cynocephalus or P. hamadryas cynocephalus), chacma baboons (Papio ursinus or P. h. ursinus), and geladas (Theropithecus gelada). First, we predict that testosterone profiles will track the reproductive profiles of each taxon across their respective breeding years. Second, we evaluate age-related changes in testosterone to determine whether several life-history transitions are associated with these changes. Subjects include males (>2.5 years) from wild populations of each taxon from whom we had fecal samples for hormone determination. Although testosterone profiles across species were broadly similar, considerable variability was found in the timing of two major changes: (1) the attainment of adult levels of testosterone, and (2) the decline in testosterone after the period of maximum production. Attainment of adult testosterone levels was delayed by one year in chacmas compared with yellows and geladas. With respect to the decline in testosterone, geladas and chacmas exhibited a significant drop after three years of maximum production, while yellows declined so gradually that no significant annual drop was ever detected. For both yellows and chacmas, increases in testosterone production preceded elevations in social dominance rank. We discuss these differences in the context of ecological and behavioral differences exhibited by these taxa. PMID:19712676

  17. Validity of the Fine Motor Area of the 12-Month Ages and Stages Questionnaire in Infants Following Major Surgery

    ERIC Educational Resources Information Center

    Smith, Cally; Wallen, Margaret; Walker, Karen; Bundy, Anita; Rolinson, Rachel; Badawi, Nadia

    2012-01-01

    The Ages and Stages Questionnaires (ASQ) are parent-report screening tools to identify infants at risk of developmental difficulties. The purpose of this study was to examine validity and internal reliability of the fine motor developmental area of the ASQ, 2nd edition (ASQ2-FM) for screening 12-month-old infants following major surgery. The…

  18. 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

  19. 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.

  20. 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…

  1. 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...

  2. 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.

  3. 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.

  4. Effect of Maternal Age on the Ratio of Cleavage and Mitochondrial DNA Copy Number in Early Developmental Stage Bovine Embryos

    PubMed Central

    TAKEO, Shun; GOTO, Hiroya; KUWAYAMA, Takehito; MONJI, Yasunori; IWATA, Hisataka

    2012-01-01

    Abstract Age-associated deterioration in both the quality and quantity of mitochondria occurs in older women. The main aim of this study was to examine the effect of age on mitochondrial DNA copy number (mtDNA number) in early developmental stage bovine embryos as well as the dynamics of mtDNA number during early embryo development. Real-time PCR was used to determine mtDNA number. In vitro-produced embryos 48 h after insemination derived from Japanese black cows, ranging in age from 25 to 209 months were categorized based on their cleavage status. There was an overall negative relationship between the age of the cow and cleavage status, to the extent that the ratio of embryos cleaved over the 4-cell stage was greater in younger cows. The mtDNA number did not differ among the cleaved status of embryos. In the next experiment, oocytes collected from each donor cow were divided into 2 groups containing 10 oocytes each, in order to compare the mtDNA number of mature oocytes and early developmental stage embryos within individuals. Upon comparing the mtDNA number between oocytes at the M2 stage and early developmental stage 48 h post insemination, mtDNA number was found to decrease in most cows, but was found to increase in some cows. In conclusion, age affects the cleaving ability of oocytes, and very old cows (> 180 months) tend to have lower mtDNA numbers in their oocytes. The change in mtDNA number during early development varied among individual cows, although overall, it showed a tendency to decrease. PMID:23269452

  5. Learning Multiple Band-Pass Filters for Sleep Stage Estimation: Towards Care Support for Aged Persons

    NASA Astrophysics Data System (ADS)

    Takadama, Keiki; Hirose, Kazuyuki; Matsushima, Hiroyasu; Hattori, Kiyohiko; Nakajima, Nobuo

    This paper proposes the sleep stage estimation method that can provide an accurate estimation for each person without connecting any devices to human's body. In particular, our method learns the appropriate multiple band-pass filters to extract the specific wave pattern of heartbeat, which is required to estimate the sleep stage. For an accurate estimation, this paper employs Learning Classifier System (LCS) as the data-mining techniques and extends it to estimate the sleep stage. Extensive experiments on five subjects in mixed health confirm the following implications: (1) the proposed method can provide more accurate sleep stage estimation than the conventional method, and (2) the sleep stage estimation calculated by the proposed method is robust regardless of the physical condition of the subject.

  6. 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

  7. Clinical stage of breast cancer by parity, age at birth, and time since birth: a progressive effect of pregnancy hormones?

    PubMed

    Albrektsen, Grethe; Heuch, Ivar; Thoresen, Steinar; Kvåle, Gunnar

    2006-01-01

    Breast cancer diagnosed during pregnancy or 1 to 2 years after birth often occurs at a late stage. Little is known about tumor characteristics in the high-risk period shortly after a childbirth. We here explore whether stage of disease differs according to timing of births. Results are based on 22,351 Norwegian breast cancer patients of parity 0 to 5, ages 20 to 74 years. The proportion of stage II to IV tumors was considerably higher among parous than nulliparous women at age <30 years (52.7% versus 36.8%, P=0.009), but similar or lower in other age groups (P(interaction)=0.029). In general, the largest proportion of stage II to IV tumors was found among women diagnosed during pregnancy or <2 years after birth. However, among women with late-age births (first or second birth >or=30 years, third birth >or=35 years), as well as women with an early second birth (<25 years), the proportion with advanced disease was rather similar or even higher among those diagnosed 2 to 6 years after birth (49.3-56.0%). The association between clinical stage and time since birth reached statistical significance among women with a late first or second birth and among all triparous women (P

  8. 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.

  9. Maternal Age of Menarche and Blood Pressure in Adolescence: Evidence from Hong Kong’s “Children of 1997” Birth Cohort

    PubMed Central

    Lai, Tsz Chun; Leung, Gabriel Matthew; Schooling, C. Mary

    2016-01-01

    Background Age of puberty has declined substantially in developed settings and is now declining in the rest of the world with economic development. Early age of puberty is associated with non-communicable diseases in adulthood, and may be a long-term driver of population health with effects over generations. In a non-Western setting, we examined the association of maternal age of menarche with blood pressure in late childhood/adolescence. Methods We used generalised estimating equations to estimate the adjusted association of maternal age of menarche with age-, sex- and height-adjusted blood pressure z-score from 10 to 16 years in Hong Kong’s population-representative birth cohort, “Children of 1997” (n = 8327). We also assessed whether associations were mediated by body mass index (BMI) or pubertal stage. Results Earlier maternal age of menarche was associated with higher systolic blood pressure in adolescence [-0.02 z-score per year older maternal age of menarche, 95% confidence interval (CI) -0.04 to -0.003]. The association of maternal age of menarche with systolic blood pressure was mediated by adiposity and/or pubertal stage at 11 years. Maternal age of menarche was not associated with diastolic blood pressure. Conclusion Earlier maternal age of puberty was associated with higher systolic blood pressure, largely mediated by adiposity, highlighting the importance of tackling childhood obesity as a public health priority in view of the secular trend of declining age of puberty. PMID:27454175

  10. 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

  11. 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

  12. Puberty stage and spontaneous descent of acquired undescended testis: implications for therapy?

    PubMed

    Sijstermans, K; Hack, W W M; van der Voort-Doedens, L M; Meijer, R W; Haasnoot, K

    2006-12-01

    We assessed spontaneous descent of acquired undescended testis (UDT) at puberty. 299 Boys (aged 1.2-16.5 years, mean 9.4) with 350 acquired-UDT were examined annually during a 12.6-year period (mean 3.1). An acquired-UDT was defined as a previously intrascrotal testis which can no longer be manipulated into a stable scrotal position. Each year, position of the testis and pubertal development according to Tanner's stages were assessed. Early puberty was defined as puberty stage G2 (testicular volume 4-9 mL), mid-puberty as puberty stages G3 (testicular volume 10 mL) and G4 (testicular volume 11-15 mL), and late puberty as puberty stage G5 (testicular volume >15 mL). Follow-up was completed if spontaneous descent had occurred, if mid-pubertal orchidopexy (ORP) had to be performed, if the boy was lost for follow-up, or if pre-pubertal ORP was performed in another hospital. In 139 boys with 164 acquired-UDT follow-up was meanwhile completed. Twelve boys with 14 UDT were lost for follow-up. In an additional 16 boys with 21 UDT, ORP was performed in another hospital. In 98 of the remaining 129 (76.0%) acquired-UDT spontaneous descent at puberty occurred. Mean follow-up was 2.5 years (range 0.2-8.5). In 70 of 98 testes (71.4%) descent occurred in early puberty, in 26 of 98 testes (26.5%) in mid-puberty, and in two testes in late puberty. In 31 of 129 testes (24.0%) ORP had to be performed at mid (30 cases) or late (one case) puberty. In this series, 98 of 129 acquired-UDT (76.0%) descended spontaneously at puberty, whereas in 31 of 129 (24.0%) pubertal ORP was performed. If ORP is postponed until puberty stage G3 (testicular volume of 10 mL) three of four acquired-UDT will descend spontaneously.

  13. The new life stage of emerging adulthood at ages 18-29 years: implications for mental health.

    PubMed

    Arnett, Jeffrey J; Žukauskienė, Rita; Sugimura, Kazumi

    2014-12-01

    Since 1960 demographic trends towards longer time in education and late age to enter into marriage and of parenthood have led to the rise of a new life stage at ages 18-29 years, now widely known as emerging adulthood in developmental psychology. In this review we present some of the demographics of emerging adulthood in high-income countries with respect to the prevalence of tertiary education and the timing of parenthood. We examine the characteristics of emerging adulthood in several regions (with a focus on mental health implications) including distinctive features of emerging adulthood in the USA, unemployment in Europe, and a shift towards greater individualism in Japan. PMID:26361316

  14. Variation in body condition indices of crimson finches by sex, breeding stage, age, time of day, and year

    PubMed Central

    Milenkaya, Olga; Weinstein, Nicole; Legge, Sarah; Walters, Jeffrey R.

    2013-01-01

    Body condition indices are increasingly applied in conservation to assess habitat quality, identify stressed populations before they decline, determine effects of disturbances, and understand mechanisms of declines. To employ condition indices in this manner, we need first to understand their baseline variability and sources of variation. Here, we used crimson finches (Neochmia phaeton), a tropical passerine, to describe the variation in seven commonly used condition indices by sex, age, breeding stage, time of day, and year. We found that packed cell volume, haemoglobin, total plasma protein, and scaled mass were all significantly affected by an interaction between sex and breeding stage. Furcular fat varied by sex and breeding stage and also trended by year, scaled mass showed a positive trend with age and varied by time of day, and haemoglobin additionally varied by year. Pectoral muscle scores varied and heterophil to lymphocyte ratio trended only by year. Year effects might reflect a response to annual variation in environmental conditions; therefore, those indices showing year effects may be especially worthy of further investigation of their potential for conservation applications. Pectoral muscle scores and heterophil to lymphocyte ratio may be particularly useful due to the lack of influence of other variables on them. For the other indices, the large variation that can be attributed to individual covariates, such as sex and breeding stage, suggests that one should not interpret the physiological condition of an individual as measured by these indices from their absolute value. Instead, the condition of an individual should be interpreted relative to conspecifics by sex, breeding stage, and possibly age. PMID:27293604

  15. Variation in body condition indices of crimson finches by sex, breeding stage, age, time of day, and year.

    PubMed

    Milenkaya, Olga; Weinstein, Nicole; Legge, Sarah; Walters, Jeffrey R

    2013-01-01

    Body condition indices are increasingly applied in conservation to assess habitat quality, identify stressed populations before they decline, determine effects of disturbances, and understand mechanisms of declines. To employ condition indices in this manner, we need first to understand their baseline variability and sources of variation. Here, we used crimson finches (Neochmia phaeton), a tropical passerine, to describe the variation in seven commonly used condition indices by sex, age, breeding stage, time of day, and year. We found that packed cell volume, haemoglobin, total plasma protein, and scaled mass were all significantly affected by an interaction between sex and breeding stage. Furcular fat varied by sex and breeding stage and also trended by year, scaled mass showed a positive trend with age and varied by time of day, and haemoglobin additionally varied by year. Pectoral muscle scores varied and heterophil to lymphocyte ratio trended only by year. Year effects might reflect a response to annual variation in environmental conditions; therefore, those indices showing year effects may be especially worthy of further investigation of their potential for conservation applications. Pectoral muscle scores and heterophil to lymphocyte ratio may be particularly useful due to the lack of influence of other variables on them. For the other indices, the large variation that can be attributed to individual covariates, such as sex and breeding stage, suggests that one should not interpret the physiological condition of an individual as measured by these indices from their absolute value. Instead, the condition of an individual should be interpreted relative to conspecifics by sex, breeding stage, and possibly age.

  16. White Matter Integrity and Reaction Time Intraindividual Variability in Healthy Aging and Early-Stage Alzheimer Disease

    PubMed Central

    Jackson, Jonathan D.; Balota, David A.; Duchek, Janet M.; Head, Denise

    2011-01-01

    Aging and early-stage Alzheimer disease (AD) have been shown to be associated with increased RT intraindividual variability (IIV, as reflected by the coefficient of variation) and an exaggeration of the slow tail of the RT distribution in attentional control tasks, based on ex-Gaussian analyses. The current study examined associations between white matter volume, IIV, and ex-Gaussian RT distribution parameters in cognitively normal aging and early-stage AD. Three RT attention tasks (Stroop, Simon, and a consonant-vowel odd-even switching task) in conjunction with MRI-based measures of cerebral and regional white matter volume were obtained in 133 cognitively normal and 33 early-stage AD individuals. Larger volumes were associated with less IIV and less slowing in the tail of the RT distribution, and larger cerebral and inferior parietal white matter volumes were associated with faster modal reaction time. Collectively, these results support a role of white matter integrity in IIV and distributional skewing, and are consistent with the hypothesis that IIV and RT distributional skewing are sensitive to breakdowns in executive control processes in normal and pathological aging. PMID:22172547

  17. APPLYING TEP MEASUREMENTS TO ASSESS THE AGING STAGE OF MARAGING 250 STEEL

    SciTech Connect

    Snir, Y.; Gelbstein, Y.; Pinkas, M.; Yeheskel, O.; Landau, A.

    2008-02-28

    Thermoelectric power (TEP) measurements had been proved as an effective method for evaluating the metallurgical state of various alloys. The current work was conducted in order to evaluate the influence of the aging state of Maraging 250 steel on TEP values. Commercial Maraging 250 steel was aged at 500 deg. C for 0.5-6 hours (hrs). TEP, hardness (Rc) and ultrasonic (US) measurements, were preformed on the as received and aged specimens. XRD measurements were used to identify the formation of precipitates (mainly Ni{sub 3}(Ti,Mo)), reverted austenite and to evaluate changes in the microstrain caused by the precipitation process. A correlation was found between the TEP and the various measurements as a function of the aging time.

  18. Applying Tep Measurements to Assess the Aging Stage of Maraging 250 Steel

    NASA Astrophysics Data System (ADS)

    Snir, Y.; Pinkas, M.; Gelbstein, Y.; Yeheskel, O.; Landau, A.

    2008-02-01

    Thermoelectric power (TEP) measurements had been proved as an effective method for evaluating the metallurgical state of various alloys. The current work was conducted in order to evaluate the influence of the aging state of Maraging 250 steel on TEP values. Commercial Maraging 250 steel was aged at 500 °C for 0.5-6 hours (hrs). TEP, hardness (Rc) and ultrasonic (US) measurements, were preformed on the as received and aged specimens. XRD measurements were used to identify the formation of precipitates (mainly Ni3(Ti,Mo)), reverted austenite and to evaluate changes in the microstrain caused by the precipitation process. A correlation was found between the TEP and the various measurements as a function of the aging time.

  19. Dental and Chronological Ages as Determinants of Peak Growth Period and Its Relationship with Dental Calcification Stages

    PubMed Central

    Litsas, George; Lucchese, Alessandra

    2016-01-01

    Purpose: To investigate the relationship between dental, chronological, and cervical vertebral maturation growth in the peak growth period, as well as to study the association between the dental calcification phases and the skeletal maturity stages during the same growth period. Methods: Subjects were selected from orthodontic pre-treatment cohorts consisting of 420 subjects where 255 were identified and enrolled into the study, comprising 145 girls and 110 boys. The lateral cephalometric and panoramic radiographs were examined from the archives of the Department of Orthodontics, Aristotle University of Thessaloniki, Greece. Dental age was assessed according to the method of Demirjian, and skeletal maturation according to the Cervical Vertebral Maturation Method. Statistical elaboration included Spearman Brown formula, descriptive statistics, Pearson’s correlation coefficient and regression analysis, paired samples t-test, and Spearman’s rho correlation coefficient. Results: Chronological and dental age showed a high correlation for both gender(r =0.741 for boys, r = 0.770 for girls, p<0.001). The strongest correlation was for the CVM Stage IV for both males (r=0.554) and females (r=0.68). The lowest correlation was for the CVM Stage III in males (r=0.433, p<0.001) and for the CVM Stage II in females (r=0.393, p>0.001). The t-test revealed statistically significant differences between these variables (p<0.001) during the peak period. A statistically significant correlation (p<0.001) between tooth calcification and CVM stages was determined. The second molars showed the highest correlation with CVM stages (CVMS) (r= 0.65 for boys, r = 0.72 for girls). Conclusion: Dental age was more advanced than chronological for both boys and girls for all CVMS. During the peak period these differences were more pronounced. Moreover, all correlations between skeletal and dental stages were statistically significant. The second molars showed the highest correlation whereas the

  20. 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

  1. [Diagnostics and therapy of dysphonia suitable for the ages and developmental stages of children and adolescents (part 2)].

    PubMed

    Fuchs, M

    2008-02-01

    The incidence of dysphonia among children and adolescents is evaluated internationally at 6 % to 25 %. Nonetheless, hoarseness as a leading symptom among children is often insufficiently recognized by their parents/attachment figures, by the young patients themselves, and even by physicians. In an overview, the hereditary and acquired organic and functional causes - including secondary organic lesions of the vocal folds - their pathomechanisms and the symptoms typical for this age group are presented. For diagnostics suitable for these age groups and developmental stages, modern methods of laryngoscopy (including stoboscopy and real-time laryngoscopy), of functional diagnostics of vocal capacity and quality as well as anamnestic and psychometric procedures for the investigation of possible psychosomatic genesis are available. Frequent therapeutic measures are vocal hygienic counseling and psycho- and family dynamic therapies. Vocal exercise treatments are particularly employed for the consequences of laryngeal surgery and with voice techniques unfavorable as a precondition for increased vocal activity. Operative measures in the sound-producing areas of the vocal apparatus and in the framework of plastic reconstruction concentrate on the optimizing of vocal capacity and quality. In clinical routine, symptoms of dysphonia in children and adolescents should be consciously registered, and any long-term hoarseness, in this age group as well, should be examined by specialized physicians using the methods suitable to the age group and the developmental stage. When the appropriate indications are present, all of the therapeutic options currently available should be discussed.

  2. 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

  3. 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

  4. [GENDER AND AGE DIFFERENCES IN THE TREATMENT OF CHRONIC HEART FAILURE AT HOSPITAL OBSERVATIONS STAGE].

    PubMed

    Dadashova, G M

    2016-01-01

    Analysis of literature shows that very little data are available on gender differences and age-specific drug use in the treatment of chronic heart failure (CHF). In this work, the character of drug therapy was studied as dependent on the age and sex of patients with CHF under in-hospital observation conditions. Among hospitalized patients with CHF, an important role is played by modern drug therapy. Gender differences were found in respect of therapy with ACE inhibitors, which was used in men more frequently than in women (89 and 78%, respectively, p <0.001). Aldosterone antagonists were used in the treatment of women much less frequently than in men (32.9 and 42%, respectively, p < 0.001). Loop diuretics are more frequently prescribed to men (48 and 40%, respectively, p < 0.001) and thiazide diuretics, to women (38.9 and 27%, respectively, p < 0.001). In older age groups, CHF treatment both in men (p < 0.05) and in women (p < 0.001) is characterized by decreased use of beta-adrenoblockers and increased use of aldosterone antagonists (p < 0.05). In women, older age groups meet increased prescription frequency of ACE inhibitors/ARBs (from 79.1 to 95.3%p < 0.01) and aldosterone antagonists (from 29.3 to 38.2% p < 0.001). PMID:27416677

  5. Development: Ages & Stages--How Children Develop a Sense of Time

    ERIC Educational Resources Information Center

    Poole, Carla; Miller, Susan A.; Church, Ellen Booth

    2006-01-01

    This article presents suggestions on how to increase awareness of a sense of time for infants up to age 6. It recommends using children's personal experiences to help them understand time concepts. Individual components of this article include: (1) "I Go Now!"--Birth to 2 (Carla Poole); (2) "Today's My Birthday!"--3 to 4 (Susan A. Miller); and (3)…

  6. Novel modulators of senescence, aging, and longevity: Small non-coding RNAs enter the stage.

    PubMed

    Grillari, Johannes; Grillari-Voglauer, Regina

    2010-04-01

    During the last decade evidence has accumulated that the aging process is driven by limited allocation of energy to somatic maintenance resulting in accumulation of stochastic damage. This damage, affecting molecules, cells, and tissues, is counteracted by genetically programmed repair, the efficiency of which thus importantly determines the life and 'health span' of organisms. Therefore, understanding the regulation of gene expression during cellular and organismal aging as well as upon exposure to various damaging events is important to understand the biology of aging and to positively influence the health span. The recent identification of small non-coding RNAs (ncRNAs), has added an additional layer of complexity to the regulation of gene expression with the classes of endogenous small inhibitory RNAs (siRNAs), PIWI-interacting RNAs (piRNAs), QDE1-interacting RNAs (qiRNAs) and microRNAs (miRNAs). Some of these ncRNAs have not yet been identified in mammalian cells and are dependent on RNA-dependent RNA polymerases. The first mammalian enzyme with such activity has only now emerged and surprisingly consists of the catalytic subunit of telomerase (hTERT) together with RMPR, an alternative RNA component. The so far most studied small non-coding RNAs, miRNAs, however, are now increasingly found to operate in the complex network of cellular aging. Recent findings show that (i) miRNAs are regulated during cellular senescence in vitro, (ii) they contribute to tissue regeneration by regulation of stem cell function, and (iii) at least one miRNA modulates the life span of the model organism C. elegans. Additionally, (iv) they act as inhibitors of proteins mediating the insulin/IGF1 and target of rapamycin (TOR) signalling, both of which are conserved modulators of organism life span. Here we will give an overview on the current status of these topics. Since little is so far known on the functions of small ncRNAs in the context of aging and longevity, the entry of the

  7. The Prognostic Impact of Molecular Subtypes and Very Young Age on Breast Conserving Surgery in Early Stage Breast Cancer

    PubMed Central

    McGuire, Kandace; Alco, Gul; Nur Pilanci, Kezban; Koksal, Ulkuhan I; Elbüken, Filiz; Erdogan, Zeynep; Agacayak, Filiz; Ilgun, Serkan; Sarsenov, Dauren; Öztürk, Alper; İğdem, Şefik; Okkan, Sait; Eralp, Yeşim; Dincer, Maktav; Ozmen, Vahit

    2016-01-01

    Background Premenopausal breast cancer with a triple-negative phenotype (TNBC) has been associated with inferior locoregional recurrence free survival (LRFS) and overall survival (OS) after breast conserving surgery (BCS). The aim of this study is to analyze the association between age, subtype, and surgical treatment on survival in young women (≤40 years) with early breast cancer in a population with a high rate of breast cancer in young women. Methods Three hundred thirty-two patients ≤40 years old with stage I-II invasive breast cancer who underwent surgery at a single institution between 1998 and 2012 were identified retrospectively. Uni- and multivariate analysis evaluated predictors of LRFS, OS, and disease free survival (DFS). Results Most patients (64.2%) underwent BCS. Mean age and follow-up time were 35 (25 ± 3.61) years, and 72 months (range, 24–252), respectively. In multivariate analysis, multicentricity/multifocality and young age (<35 years) independently predicted for poorer DFS and OS. Those aged 35–40 years had higher LRFS and DFS than those <35 in the mastectomy group (p=0.007 and p=0.039, respectively). Patients with TNBC had lower OS compared with patients with luminal A subtype (p=0.042), and those who underwent BCS had higher OS than patients after mastectomy (p=0.015). Conclusion Young age (< 35 years) is an independent predictor of poorer OS and DFS as compared with ages 35–40, even in countries with a lower average age of breast cancer presentation. In addition, TNBC in the young predicts for poorer OS. BCS can be performed in young patients with TNBC, despite their poorer overall survival. PMID:27433412

  8. 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

  9. 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.

  10. 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'…

  11. 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…

  12. 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…

  13. 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…

  14. Apolipoprotein D takes center stage in the stress response of the aging and degenerative brain☆

    PubMed Central

    Dassati, Sarah; Waldner, Andreas; Schweigreiter, Rüdiger

    2014-01-01

    Apolipoprotein D (ApoD) is an ancient member of the lipocalin family with a high degree of sequence conservation from insects to mammals. It is not structurally related to other major apolipoproteins and has been known as a small, soluble carrier protein of lipophilic molecules that is mostly expressed in neurons and glial cells within the central and peripheral nervous system. Recent data indicate that ApoD not only supplies cells with lipophilic molecules, but also controls the fate of these ligands by modulating their stability and oxidation status. Of particular interest is the binding of ApoD to arachidonic acid and its derivatives, which play a central role in healthy brain function. ApoD has been shown to act as a catalyst in the reduction of peroxidized eicosanoids and to attenuate lipid peroxidation in the brain. Manipulating its expression level in fruit flies and mice has demonstrated that ApoD has a favorable effect on both stress resistance and life span. The APOD gene is the gene that is upregulated the most in the aging human brain. Furthermore, ApoD levels in the nervous system are elevated in a large number of neurologic disorders including Alzheimer's disease, schizophrenia, and stroke. There is increasing evidence for a prominent neuroprotective role of ApoD because of its antioxidant and anti-inflammatory activity. ApoD emerges as an evolutionarily conserved anti-stress protein that is induced by oxidative stress and inflammation and may prove to be an effective therapeutic agent against a variety of neuropathologies, and even against aging. PMID:24612673

  15. 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…

  16. Age-stage, two-sex life table of Brontispa longissima (Gestro) (Coleoptera: Hispidae) feeding on four palm plant varieties.

    PubMed

    Jin, Tao; Lin, Yu-Ying; Jin, Qi-An; Wen, Hai-Bo; Peng, Zheng-Qiang

    2012-10-01

    The life history of Brontispa longissima (Gestro) (Coleoptera: Hispidae), reared under laboratory conditions on leaves of coconut (Cocos nucifera L.), royal palm [Roystonea regia (Kunth) O.F.Cook], bottle palm [Hyophorbe lagenicaulis (L. Bailey) H.E.Moore], and fishtail palm (Caryota ochlandra Hance) was analyzed using age-stage, two-sex life table. Means and standard errors of population growth parameters were calculated using the jackknife method. Moreover, survival rate and fecundity data were applied to project the population for revealing the different stage structure. The mean intrinsic rates of population growth when reared on each respective leaf type were 0.032, 0.031, 0.019, and 0.044. Individuals reared on C. nucifera achieved the highest net reproduction rate at 114.5 offspring per female. The mean generation times of B. longissima ranged from 93.2 d (reared on C. ochlandrai) to 161.5 d (reared on H. lagenicaulis). Projections from survival rate and fecundity data indicated that B. longissima populations can row considerably faster on C. ochlandra than on the other three host plants. The results validate the two-stage life history approach taken, providing an essential tool for developing and testing future control strategies. PMID:23068179

  17. Prognosis of Pregnancy-Associated Gastric Cancer: An Age-, Sex-, and Stage-Matched Case-Control Study

    PubMed Central

    Song, Min Jeong; Park, Young Soo; Song, Ho June; Park, Se Jeong; Ahn, Ji Yong; Choi, Kee Don; Lee, Gin Hyug; Jung, Hwoon-Yong; Yook, Jeong Hwan; Kim, Byung Sik

    2016-01-01

    Background/Aims Pregnancy-associated gastric cancer is a rare condition. This case-control study was performed to identify the clinicopathological features and prognostic factors of pregnancy-associated gastric cancer. Methods All consecutive patients who presented to our tertiary referral hospital with pregnancy-associated gastric cancer from 1991 to 2012 were identified. Two age-, sex-, and stage-matched controls for each case were also identified from the records. Clinicopathological, gynecological, and oncological outcomes were recorded. Immunohistochemical staining was performed for estrogen receptor, progesterone receptor, epidermal growth factor receptor, human epidermal growth factor receptor, and E-cadherin. Fluorescence in situ hybridization was performed for fibroblast growth factor receptor 2. Results The median overall survival rates of the pregnancy-associated gastric cancer and control groups were 7.0 months and 15.0 months, respectively (p=0.189). Poor prognostic factors included advanced stage and tumor location in the corpus or the entire stomach but not pregnancy status or loss of E-cadherin. Pregnancy-associated gastric cancer was associated with a longer time from diagnosis to treatment (21 days vs 7 days, p=0.021). The two groups did not differ in the expression of the receptors or E-cadherin. Conclusions The dismal prognosis of pregnancy-associated gastric cancer may related to the tumor stage and location rather than to pregnancy itself. PMID:27114414

  18. Age-Stage, Two-Sex Life Table Characteristics of Aedes albopictus and Aedes Aegypti in Penang Island, Malaysia.

    PubMed

    Maimusa, Hamisu A; Ahmad, Abu Hassan; Kassim, Nur Faeza A; Rahim, Junaid

    2016-03-01

    The life table developmental attributes of laboratory colonies of wild strains of Aedes albopictus and Aedes aegypti were analyzed and compared based on the age-stage, two-sex life table. Findings inclusive in this study are: adult preoviposition periods, total preoviposition period, mean intrinsic rate of increase (r), mean finite rate of increase (λ), net reproductive rates (R0), and mean generation time (T). The total preadult development time was 9.47 days for Ae. albopictus and 8.76 days for Ae. aegypti. The life expectancy was 19.01 days for Ae. albopictus and 19.94 days for Ae. aegypti. Mortality occurred mostly during the adult stage. The mean development time for each stage insignificantly correlated with temperature for Ae. albopictus (r  =  -0.208, P > 0.05) and (r  =  -0.312, P > 0.05) for Ae. aegypti. The population parameters suggest that Ae. albopictus and Ae. aegypti populations are r-strategists characterized by a high r, a large R0, and short T. This present study provides the first report to compare the life parameters of Ae. albopictus and Ae. aegypti strains from Penang island, Malaysia.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. Work-family conflict among members of full-time dual-earner couples: an examination of family life stage, gender, and age.

    PubMed

    Allen, Tammy D; Finkelstein, Lisa M

    2014-07-01

    Based on cross-sectional data from the 2008 National Study of the Changing Workforce, this study investigates relationships between gender, age, and work-family conflict across 6 family life stages. Participants were 690 married/partnered employees who worked 35 or more hours a week. Results indicated a small but negative relationship between age and work-family conflict. Work-family conflict was also associated with family stage, with the least amount of conflict occurring during the empty nest stage and the most occurring when the youngest child in the home was 5 years of age or younger. Gender differences were also observed. Specifically, men reported more work interference with family than did women when the youngest child in the home was a teen. Women overall reported more family interference with work than did men. Results concerning age and gender revealed a different pattern demonstrating that family stage is not simply a proxy for age. Age had a main effect on work-to-family conflict that was monotonic in nature and on family to-work conflict that was linear in nature. In conclusion, the results indicate gender, age, and family stage each uniquely relate to work-family conflict.

  8. Age-dependent role for Ras-GRF1 in the late stages of adult neurogenesis in the dentate gyrus.

    PubMed

    Darcy, Michael J; Trouche, Stéphanie; Jin, Shan-Xue; Feig, Larry A

    2014-03-01

    The dentate gyrus of the hippocampus plays a pivotal role in pattern separation, a process required for the behavioral task of contextual discrimination. One unique feature of the dentate gyrus that contributes to pattern separation is adult neurogenesis, where newly born neurons play a distinct role in neuronal circuitry. Moreover,the function of neurogenesis in this brain region differs in adolescent and adult mice. The signaling mechanisms that differentially regulate the distinct steps of adult neurogenesis in adolescence and adulthood remain poorly understood. We used mice lacking RASGRF1(GRF1), a calcium-dependent exchange factor that regulates synaptic plasticity and participates in contextual discrimination performed by mice, to test whether GRF1 plays a role in adult neurogenesis.We show Grf1 knockout mice begin to display a defect in neurogenesis at the onset of adulthood (~2 months of age), when wild-type mice first acquire the ability to distinguish between closely related contexts. At this age, young hippocampal neurons in Grf1 knockout mice display severely reduced dendritic arborization. By 3 months of age, new neuron survival is also impaired. BrdU labeling of new neurons in 2-month-old Grf1 knockout mice shows they begin to display reduced survival between 2 and 3 weeks after birth, just as new neurons begin to develop complex dendritic morphology and transition into using glutamatergic excitatory input. Interestingly, GRF1 expression appears in new neurons at the developmental stage when GRF1 loss begins to effect neuronal function. In addition, we induced a similar loss of new hippocampal neurons by knocking down expression of GRF1 solely in new neurons by injecting retrovirus that express shRNA against GRF1 into the dentate gyrus. Together, these findings show that GRF1 expressed in new neurons promotes late stages of adult neurogenesis. Overall our findings show GRF1 to be an age-dependent regulator of adult hippocampal neurogenesis, which

  9. Dental age assessment of adolescents and emerging adults in United Kingdom Caucasians using censored data for stage H of third molar roots.

    PubMed

    Boonpitaksathit, Teelana; Hunt, Nigel; Roberts, Graham J; Petrie, Aviva; Lucas, Victoria S

    2011-10-01

    The root of the third permanent molar is the only dental structure that continues development after completion of growth of the second permanent molar. It is claimed that the lack of a clearly defined end point for completion of growth of the third permanent molar means that this tooth cannot be used for dental age assessment. The aim of this study was to estimate the mean age of attainment of the four stages (E, F, G, and H) of root development of the third molar. The way in which the end point of completion of stage H can be identified is described. A total of 1223 dental panoramic tomographs (DPTs) available in the archives of the Eastman Dental Hospital, London, were used for this study. The ages of the subjects ranged from 12.6 to 24.9 years with 63 per cent of the sample being female. Demirjan's tooth development stages (TDSs), for the first and second molars, were applied to the third molars by a single examiner. For each of stages E, F, and G and for stage H censored data, the mean ages of the males and females were compared, separately within each tooth morphology type using the two sample t-test (P < 0.01). The same test was used to compare the mean ages of the upper and lower third molars on each side, separately for each gender. The mean age of attainment and the 99 per cent confidence interval (CI) for each TDS were calculated for each third molar. The final stage H data were appropriately censored to exclude data above the age of completion of root growth. The results showed that, for each gender, the age in years at which individuals attained each of the four TDSs was approximately normally distributed. The mean age for appropriately censored data was always lower than the corresponding mean age of the inappropriately censored data for stage H (male UR8 19.57, UL8 19.53, LL8 19.91, and LR8 20.02 and female UR8 20.08, UL8 20.13, LL8 20.78, and LR8 20.70). This inappropriately censored data overestimated the mean age for stage H. The appropriately

  10. Regular physical activity is associated with improved small artery distensibility in young to middle-age stage 1 hypertensives.

    PubMed

    Saladini, Francesca; Benetti, Elisabetta; Mos, Lucio; Mazzer, Adriano; Casiglia, Edoardo; Palatini, Paolo

    2014-12-01

    The aim of the present study was to investigate the association of physical activity with small artery elasticity in the early stage of hypertension. We examined 366 young-to-middle-age stage 1 hypertensives (mean blood pressure 145.6±10.3/92.5±5.8 mmHg), divided into two categories of physical activity, sedentary (n=264) and non-sedentary (n=102) subjects. The augmentation index was measured using the Specaway DAT System. Small artery compliance (C2) was measured by applanation tonometry, at the radial artery, with an HDI CR2000 device. After 6 years of follow-up, arterial distensibility assessment was repeated in 151 subjects. Heart rate was lower in active than in sedentary subjects (71.2±8.9 vs 76.6±9.7 bpm, p<0.001). After adjusting for age, sex, heart rate, smoking, and blood pressure, C2 was higher (8.0±2.6 vs 6.4±3.0 ml/mmHg × 100, p=0.008) in non-sedentary than in sedentary patients. The augmentation index was smaller in the former (8.8±20.1 vs 16.8±26.5%, p=0.044) but the difference lost statistical significance after further adjustment for blood pressure. After 6 years, C2 was still higher in the non-sedentary than sedentary subjects. In addition, an improvement in the augmentation index accompanied by a decline in total peripheral resistance was found in the former. These data show that regular physical activity is associated with improved small artery elasticity in the early phase of hypertension. This association persists over time and is independent of blood pressure and heart rate.

  11. "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

  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. Ages and Stages: Teen

    MedlinePlus

    ... Featured Article Meningococcal Disease: Information for Teens and College Students Certain teens and young adults have a higher ... Managing Money Meningococcal Disease: Information for Teens and College Students Mental Health and Teens: Watch for Danger Signs ...

  14. The assessment of developmental status using the Ages and Stages questionnaire-3 in nutritional research in north Indian young children

    PubMed Central

    2013-01-01

    Objective and background For large epidemiological studies in low and middle-income countries, inexpensive and easily administered developmental assessment tools are called for. This report evaluates the feasibility of the assessment tool Ages and Stages Questionnaire 3.edition (ASQ-3) “home procedure” in a field trial in 422 North Indian young children. Methods ASQ-3 was translated and adjusted for a North Indian Hindi setting. Three examiners were trained by a clinical psychologist to perform the assessments. During the main study, ten % of the assessments were done by two examiners to estimate inter-observer agreement. During all sessions, the examiners recorded whether the scoring was based on observation of the skill during the session, or on caregiver’s report of the child’s skill. Intra class correlation coefficient was calculated to estimate the agreement between the raters and between the raters and a gold standard. Pearson product moment correlation coefficient and standardized alphas were calculated to measure internal consistency. Principal findings Inter-observer agreement was strong both during training exercises and during the main study. In the Motor subscales and the Problem Solving subscale most items could be observed during the session. The standardized alphas for the total ASQ-3 scale across all ages were strong, while the alpha values for the different subscales and age levels varied. The correlations between the total score and the subscale scores were consistently strong, while the correlations between subscale scores were moderate. Conclusions/significance We found that the translated and adjusted ASQ-3 “home procedure” was a feasible procedure for the collection of reliable data on the developmental status in infants and young children. Examiners were effectively trained over a short period of time, and the total ASQ scores showed adequate variability. However, further adjustments are needed to obtain satisfying alpha values in

  15. Palynology, geochemistry and Re-Os age of the Lower-Middle Pennsylvanian stage boundary, central Appalachian basin, USA

    NASA Astrophysics Data System (ADS)

    Geboy, N.; Tripathy, G. R.; Ruppert, L. F.; Eble, C. F.; Blake, B. M.; Hannah, J. L.; Stein, H. J.

    2014-12-01

    Wales and Germany and therefore has implications across the Carboniferous Euramerican Belt. Further, the Betsie has been interpreted to represent the Lower-Middle Pennsylvanian stage boundary in North America, making this directly measured age an important marker not only within the CAB but also for refinement of the Carboniferous timescale.

  16. The comparison between measurement of open apices of third molars and Demirjian stages to test chronological age of over 18 year olds in living subjects.

    PubMed

    Cameriere, R; Ferrante, L; De Angelis, D; Scarpino, F; Galli, F

    2008-11-01

    This paper concerns a method for assessing adult age based on the relationship between age and the third molar maturity index (I(3M)), which is related to the measurement of the open apices of the third molar. Furthermore, this method was compared to those based on Demirjian's stages G and H. The sample consisted of 906 Caucasian individuals aged between 14 and 23 years (53.6% females and 46.4% males). Orthopantomographs were analyzed by two observers and calibrated by means of the concordance correlation coefficient for the reproducibility of the third molar maturity index (I(3M)) and kappa statistics for reproducibility of the Demirjian stages. Probabilities for an individual to be older than 18 years of age (adult age) were derived using the measurements of the third molar maturity index (I(3M)). These results were exploited to set out a threshold value to assign an individual to juvenile or adult age. A cutoff value of I(3M) = 0.08 was taken. The sensitivity of this test was 70% and specificity was 98%. Furthermore, the proportion of individuals with a correct classification was 83%. The results of the test showed a better specificity when compared to the choice of stage G and a better sensitivity when compared to the choice of stage H for adult age.

  17. 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

  18. 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.

  19. 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

  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. 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

  2. The influence of the sexual stages of adolescent boys on the circumference of the arm, muscle area and skinfold measurements.

    PubMed

    Derman, Orhan; Yalcin, S Songul; Kanbur, Nuray; Kinik, Erol

    2002-01-01

    The purpose of this study was to detect the changes in the circumference of the arm, skinfold thickness (SFT), arm muscle area (AMA) and arm fat area (AFA), during the sexual development of healthy adolescent boys. This study was done with 74 adolescent boys, aged 9-17 years, with no chronic diseases, no developmental delay, no current medication with height ages appropriate for their bone ages, and body mass indexes between 50-75 percentiles. Body weight and height, the circumference of the arm and the SFT were measured. Body mass index, AMA and AFA were calculated. The mean arm circumference and AMA increased significantly from Tanner stage 1 to 5. AMA was significantly and positively correlated with age, weight, height, body mass index, arm circumference, SFT. After adjusting for Tanner stages, AMA was not correlated with age. A significant negative correlation was found between AMA and arm fat area. In the present study, it was seen that the sexual stages affected the circumference of arm, AMA, and the skinfold thickness in healthy adolescent boys, who were appropriate for their bone ages, and had good nutritional status. Further studies are required to detect the effect of pubertal stage on arm anthropometry in different nutritional status including obesity and malnutrition.

  3. 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.

  4. 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

  5. The experiences of close persons caring for people with chronic kidney disease stage 5 on conservative kidney management: Contested discourses of ageing

    PubMed Central

    Myers, Jason; Smith, Glenn; Higgs, Paul; Burns, Aine; Hopkins, Katherine; Jones, Louise

    2014-01-01

    Chronic kidney disease stage 5 is a global health challenge in the context of population ageing across the world. The range of treatment options available to patients at all ages has increased and includes transplantation and dialysis. However, these options are often seen as inappropriate for older frailer patients who are now offered the option of conservative kidney management, which is presented as a non-invasive alternative to dialysis, involving symptom management and addressing psychosocial needs. In this study, we conducted qualitative interviews with 26 close persons caring for someone with chronic kidney disease stage 5 in the United Kingdom to investigate how conservative kidney management interacted with implicit ideas of ageing, in both the experience of conservative kidney management and the understanding of the prognosis and future care of the kidney disease. Our findings highlighted participant confusion about the nature of conservative kidney management, which stems from an initial lack of clarity about how conservative kidney management differed from conventional treatments for chronic kidney disease stage 5. In particular, some respondents were not aware of the implicit palliative nature of the intervention or indeed the inevitable end-of-life issues. Although these findings can be situated within the context of communication failure, we would further argue that they also bring to the surface tensions in the discourses surrounding ageing and old age, drawing on the use of a ‘natural’ and a ‘normal’ paradigm of ageing. In the context of chronic kidney disease stage 5, more patients are being dialysed at older ages, but conservative kidney management is being advanced as a better option than dialysis in terms of quality of life and experience. However, in doing so, conservative kidney management implicitly draws on a notion of older age that echoes natural ageing rather than advocate a more interventionist approach. The role of discourses

  6. The experiences of close persons caring for people with chronic kidney disease stage 5 on conservative kidney management: contested discourses of ageing.

    PubMed

    Low, Joe; Myers, Jason; Smith, Glenn; Higgs, Paul; Burns, Aine; Hopkins, Katherine; Jones, Louise

    2014-11-01

    Chronic kidney disease stage 5 is a global health challenge in the context of population ageing across the world. The range of treatment options available to patients at all ages has increased and includes transplantation and dialysis. However, these options are often seen as inappropriate for older frailer patients who are now offered the option of conservative kidney management, which is presented as a non-invasive alternative to dialysis, involving symptom management and addressing psychosocial needs. In this study, we conducted qualitative interviews with 26 close persons caring for someone with chronic kidney disease stage 5 in the United Kingdom to investigate how conservative kidney management interacted with implicit ideas of ageing, in both the experience of conservative kidney management and the understanding of the prognosis and future care of the kidney disease. Our findings highlighted participant confusion about the nature of conservative kidney management, which stems from an initial lack of clarity about how conservative kidney management differed from conventional treatments for chronic kidney disease stage 5. In particular, some respondents were not aware of the implicit palliative nature of the intervention or indeed the inevitable end-of-life issues. Although these findings can be situated within the context of communication failure, we would further argue that they also bring to the surface tensions in the discourses surrounding ageing and old age, drawing on the use of a 'natural' and a 'normal' paradigm of ageing. In the context of chronic kidney disease stage 5, more patients are being dialysed at older ages, but conservative kidney management is being advanced as a better option than dialysis in terms of quality of life and experience. However, in doing so, conservative kidney management implicitly draws on a notion of older age that echoes natural ageing rather than advocate a more interventionist approach. The role of discourses of ageing

  7. The experiences of close persons caring for people with chronic kidney disease stage 5 on conservative kidney management: contested discourses of ageing.

    PubMed

    Low, Joe; Myers, Jason; Smith, Glenn; Higgs, Paul; Burns, Aine; Hopkins, Katherine; Jones, Louise

    2014-11-01

    Chronic kidney disease stage 5 is a global health challenge in the context of population ageing across the world. The range of treatment options available to patients at all ages has increased and includes transplantation and dialysis. However, these options are often seen as inappropriate for older frailer patients who are now offered the option of conservative kidney management, which is presented as a non-invasive alternative to dialysis, involving symptom management and addressing psychosocial needs. In this study, we conducted qualitative interviews with 26 close persons caring for someone with chronic kidney disease stage 5 in the United Kingdom to investigate how conservative kidney management interacted with implicit ideas of ageing, in both the experience of conservative kidney management and the understanding of the prognosis and future care of the kidney disease. Our findings highlighted participant confusion about the nature of conservative kidney management, which stems from an initial lack of clarity about how conservative kidney management differed from conventional treatments for chronic kidney disease stage 5. In particular, some respondents were not aware of the implicit palliative nature of the intervention or indeed the inevitable end-of-life issues. Although these findings can be situated within the context of communication failure, we would further argue that they also bring to the surface tensions in the discourses surrounding ageing and old age, drawing on the use of a 'natural' and a 'normal' paradigm of ageing. In the context of chronic kidney disease stage 5, more patients are being dialysed at older ages, but conservative kidney management is being advanced as a better option than dialysis in terms of quality of life and experience. However, in doing so, conservative kidney management implicitly draws on a notion of older age that echoes natural ageing rather than advocate a more interventionist approach. The role of discourses of ageing

  8. 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

  9. 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...

  10. Chemical immobilization of adult female Weddell seals with tiletamine and zolazepam: effects of age, condition and stage of lactation

    PubMed Central

    Wheatley, Kathryn E; Bradshaw, Corey JA; Harcourt, Robert G; Davis, Lloyd S; Hindell, Mark A

    2006-01-01

    Background Chemical immobilization of Weddell seals (Leptonychotes weddellii) has previously been, for the most part, problematic and this has been mainly attributed to the type of immobilizing agent used. In addition to individual sensitivity, physiological status may play an important role. We investigated the use of the intravenous administration of a 1:1 mixture of tiletamine and zolazepam (Telazol®) to immobilize adult females at different points during a physiologically demanding 5–6 week lactation period. We also compared performance between IV and IM injection of the same mixture. Results The tiletamine:zolazepam mixture administered intravenously was an effective method for immobilization with no fatalities or pronounced apnoeas in 106 procedures; however, there was a 25 % (one animal in four) mortality rate with intramuscular administration. Induction time was slightly longer for females at the end of lactation (54.9 ± 2.3 seconds) than at post-parturition (48.2 ± 2.9 seconds). In addition, the number of previous captures had a positive effect on induction time. There was no evidence for effects due to age, condition (total body lipid), stage of lactation or number of captures on recovery time. Conclusion We suggest that intravenous administration of tiletamine and zolazepam is an effective and safe immobilizing agent for female Weddell seals. Although individual traits could not explain variation in recovery time, we suggest careful monitoring of recovery times during longitudinal studies (> 2 captures). We show that physiological pressures do not substantially affect response to chemical immobilization with this mixture; however, consideration must be taken for differences that may exist for immobilization of adult males and juveniles. Nevertheless, we recommend a mass-specific dose of 0.50 – 0.65 mg/kg for future procedures with adult female Weddell seals and a starting dose of 0.50 mg/kg for other age classes and other phocid seals. PMID

  11. Developmental screening in a Canadian First Nation (Mohawk): psychometric properties and adaptations of ages & stages questionnaires (2nd edition)

    PubMed Central

    2014-01-01

    Background The need for early intervention tools adapted to the First Nation culture is well documented. However, standards derived from First Nation communities are absent from the literature. This study examines the psychometric properties of an adaptation of a caregiver-completed screening tool, the Ages & Stages Questionnaires (ASQ), for the Mohawk population. Methods Participants who completed the questionnaires include 17 teachers, along with the parents of 282 children (130 girls and 152 boys) between the ages of 9 and 66 months who attend the Child and Family Center Mohawk Territory, Quebec. Results For the internal consistency of the four questionnaires (36-, 42-, 48- and 54-month intervals), Cronbach’s alphas varied between .61 and .84. Five results were below 0.60: “gross motor” (Q36 and Q42), “problem solving” (Q36) and “personal-social” (Q36 and Q42). A comparison of the results shows that parents and teachers agreed in 85% of the cases concerning the referral of the child for further evaluation. Moreover, the group discussion with the parents revealed that the use of the questionnaire was appreciated and was deemed appropriate for use within the community. Conclusion The results show that the ASQ is a screening test that may be appropriate for use with children from communities that are seemingly very different in terms of geographic, climatic and cultural backgrounds. This preliminary study with the Child and Family Center appears to support further study and the use of the ASQ with the Mohawk population. PMID:24467769

  12. 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

  13. Relationship between Age and pre-End Stage Renal Disease Care in Elderly Patients Treated With Hemodialysis

    PubMed Central

    Harford, Rubette; Clark, Mary Jo; Norris, Keith C.; Yan, Guofen

    2016-01-01

    Receipt of pre-end-stage renal disease (ESRD) clinical care can improve outcomes for patients treated with maintenance hemodialysis (MHD). The study addressed age-related variations in receipt of a composite of recommended care to include nephrologist and dietician care and use of arterio-venous fistula at first outpatient MHD. Less than 2% of patients treated with MHD received all three forms of pre-ESRD care, and 63.3% received none of the three elements of care. The mean number of pre-ESRD care elements received by the oldest group (≥80 years) did not differ from the youngest group (<55 years), but was less than the 55-66 and 67-79 years groups; adjusted ratios of 0.93 (0.92-0.94; p<0.001) and 0.94 (0.92-0.95; p<0.001), respectively. A major effort is needed to ensure comprehensive pre-ESRD care for all patients with advanced CKD, especially for the youngest and oldest patient groups, who were less likely to receive recommended pre-ESRD care. PMID:27254965

  14. Electrodeposition and isothermal aging of Co and Mn layers on stainless steel for interconnectors: Initial stages of spinel phase formation

    NASA Astrophysics Data System (ADS)

    Pinto, R.; Carmezim, M. J.; Montemor, M. F.

    2014-06-01

    Electrodeposited Co and Mn spinel phase oxides for application as coatings for metallic interconnectors in Solid Oxide Fuel Cells were prepared. The study aims at understanding the initial stages of transformation of the metallic layers into the spinel phase. Co and Mn metallic layers were sequentially deposited over AISI 430 stainless steel substrate from acidic sulfate solutions and annealed in oxidizing and inert atmospheres between 600 °C and 800 °C. The coatings obtained showed a thickness above 20 μm. After 1 h of isothermal aging the coatings were composed of layers of un-reacted metallic elements and Mn based oxides. The spinel phase was studied by XRD and revealed Mn based tetragonal structure Mn3O4 with Co in solid solution and a non-determined Co/Mn ratio. According to EDS measurements this ratio should vary with depth. Full conversion was not obtained at these time frames with the presence other Mn oxides (MnO and Mn2O3). In inert atmosphere, the allotropic Mn transformation from α to β phase was detected. No outward diffusion of Cr was detected, due to the short exposure times.

  15. Relationship Between Age and Pre-End Stage Renal Disease Care in Elderly Patients Treated with Maintenance Hemodialysis.

    PubMed

    Harford, Rubette; Clark, Mary Jo; Norris, Keith C; Yan, Guofen

    2016-01-01

    Receipt of pre-end stage renal disease (ESRD) clinical care can improve outcomes for patients treated with maintenance hemodialysis (HD). This study addressed age-related variations in receipt of a composite of recommended care to include nephrologist and dietician care, and use of an arteriovenous fistula at first outpatient maintenance HD. Less than 2% of patients treated with maintenance HD received all three forms of pre-ESRD care, and 63.3% received none of the three elements of care. The mean number of pre-ESRD care elements received by the oldest group (80 years and older) did not differ from the youngest group (less than 55 years), but was less than the 55 to 66 and 67 to 79 years groups; adjusted ratios of 0.93 (0.92 to 0.94; p < 0.001) and 0.94 (0.92 to 0.95; p < 0.001), respectively. A major effort is needed to ensure comprehensive pre-ESRD care for all patients with advanced chronic kidney disease (CKD), especially for the youngest and oldest patient groups, who were less likely to receive recommended pre-ESRD care.

  16. Relationship Between Age and Pre-End Stage Renal Disease Care in Elderly Patients Treated with Maintenance Hemodialysis.

    PubMed

    Harford, Rubette; Clark, Mary Jo; Norris, Keith C; Yan, Guofen

    2016-01-01

    Receipt of pre-end stage renal disease (ESRD) clinical care can improve outcomes for patients treated with maintenance hemodialysis (HD). This study addressed age-related variations in receipt of a composite of recommended care to include nephrologist and dietician care, and use of an arteriovenous fistula at first outpatient maintenance HD. Less than 2% of patients treated with maintenance HD received all three forms of pre-ESRD care, and 63.3% received none of the three elements of care. The mean number of pre-ESRD care elements received by the oldest group (80 years and older) did not differ from the youngest group (less than 55 years), but was less than the 55 to 66 and 67 to 79 years groups; adjusted ratios of 0.93 (0.92 to 0.94; p < 0.001) and 0.94 (0.92 to 0.95; p < 0.001), respectively. A major effort is needed to ensure comprehensive pre-ESRD care for all patients with advanced chronic kidney disease (CKD), especially for the youngest and oldest patient groups, who were less likely to receive recommended pre-ESRD care. PMID:27254965

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. Sustained expression of a neuron-specific isoform of the Taf1 gene in development stages and aging in mice

    SciTech Connect

    Jambaldorj, Jamiyansuren; Makino, Satoshi; Munkhbat, Batmunkh; Tamiya, Gen

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer We identified the mouse homologue of neuron-specific TAF1 (N-Taf1). Black-Right-Pointing-Pointer Taf1 mRNA was expressed in most tissues and cell lines. Black-Right-Pointing-Pointer N-Taf1 mRNA was expressed in the brain and Neuroblastoma N2a cell lines. Black-Right-Pointing-Pointer Taf1 and N-Taf1 showed different expression profile in development stage and aging. -- Abstract: TATA-box binding protein associated factor 1 (TAF1) protein is the largest and the essential component of the TFIID complex in the pathway of RNA polymerase II-mediated gene transcription, and it regulates transcription of a large number of genes related to cell division. The neuron-specific isoform of the TAF1 gene (N-TAF1), which we reported previously, may have an essential role in neurons through transcriptional regulation of many neuron-specific genes. In the present study, we cloned the full-length cDNA that encodes the mouse homologue of N-TAF1 (N-Taf1) protein. By carrying out of real time RT-PCR, we investigated the expression analysis of the N-Taf1 mRNA in mouse tissues and cell lines. As well as the human N-TAF1, the N-Taf1 showed limited expression in the brain and neuroblastoma, whereas Taf1 expressed elsewhere. Furthermore, in mouse embryo head or mouse brain, mRNA expression of TAF1 changes dramatically during development but N-Taf1 showed sustained expression. Our result suggests that the N-Taf1 gene has an important role in non-dividing neuronal cell rather than in cell division and proliferation during neurogenesis.

  4. The rates of change of the stochastic trajectories of acceleration variability are a good predictor of normal aging and of the stage of Parkinson's disease

    PubMed Central

    Torres, Elizabeth B.

    2013-01-01

    The accelerometer data from mobile smart phones provide stochastic trajectories that change over time. This rate of change is unique to each person and can be well-characterized by the continuous two-parameter family of Gamma probability distributions. Accordingly, on the Gamma plane each participant can be uniquely localized by the shape and the scale parameters of the Gamma probability distribution. The scatter of such points contains information that can unambiguously separate the normal controls (NC) from those patients with Parkinson's disease (PD) that are at a later stage of the disease. In general normal aging seems conducive of more predictable patterns of variation in the accelerometer data. Yet this trend breaks down in PD where the statistical signatures seem to be a more relevant predictor of the stage of the disease. Those patients at a later stage of the disease have more random and noisier patterns than those in the earlier stages, whose statistics resemble those of the older NC. Overall the peak rates of change of the stochastic trajectories of the accelerometer are a good predictor of the stage of PD and of the age of a “normally” aging individual. PMID:23882193

  5. Generation Changes over the Period of 1986-2006 in the Physical Fitness of Boys Aged 7-19 from Eastern Poland at Particular Stages of Education

    ERIC Educational Resources Information Center

    Saczuk, Jerzy; Wasiluk, Agnieszka; Zalech, Miroslaw

    2012-01-01

    Study aim: To assess the size of secular trends in the physical fitness of boys from eastern Poland taking into consideration stages of education. Material and methods: The physical fitness results of boys aged 7-19 years living in eastern regions of Poland were analyzed: 3188 students were examined in 1986 while in 2006 the research included 10…

  6. Evaluation of the Turkish Version of the "Ages and Stages Questionnaires: Social-Emotional" in Identifying Children with Social-Emotional Problems

    ERIC Educational Resources Information Center

    Kucuker, Sevgi; Kapci, Emine Gul; Uslu, Runa Idil

    2011-01-01

    The applicability of the Age and Stages Questionnaires: Social Emotional (ASQ-SE; J. Squires, D. Bricker & E. Twombly, 2003) for Turkish children was examined. A total of 608 mothers completed the ASQ-SE's. Overall sensitivity and overall specificity were 83.7% and 89.9%, respectively. Test-retest reliability, assessed by classifying children as…

  7. Multi-stage uplift of the Colorado Plateau and the age of Grand Canyon and precursor canyons

    NASA Astrophysics Data System (ADS)

    Karlstrom, K. E.; Lee, J. P.; Kelley, S. A.; Crow, R.

    2012-12-01

    Debates about the age of Grand Canyon link to debates about the timing of surface uplift(s) of the Colorado Plateau- Rocky Mountain (CP-RM) region. One "old Grand Canyon" model proposes that a paleocanyon of almost the same depth and location as today's Grand Canyon was carved by a NE-flowing "California" paleoriver 80-70 Ma, then was re-used at ~55 Ma by a SW-flowing "Arizona" paleoriver. This model postulates the CP-RM region was uplifted to near modern elevations during the Laramide orogeny. A second model postulates a 17 Ma Grand Canyon; this time corresponds to Basin and Range extension and postulated mantle-driven surface uplift. The "young Grand Canyon" model postulates that >2/3 of modern Grand Canyon was carved by W-flowing Colorado River that became integrated to the Gulf of California at 5-6 Ma during Neogene mantle-driven uplift of the CP/RM region. Thermochronologic data are poised to substantially resolve these debates. Our thermochronology dataset combines published and new apatite fission-track and helium analyses, and joint thermal history modeling using both systems. This dataset reveals three major cooling episodes: 1) a multi-stage Sevier-Laramide contraction episode from about 90 Ma to 50 Ma with structural relief on upwarps on the order 0.5-1 km, compatible with a similar magnitude of surface uplift; 2) 30-20 Ma cooling that was associated with denudation and northward cliff retreat of most of the Mesozoic section from Grand Canyon region; 3) <10 Ma cooling that is best documented in eastern Grand Canyon as part of a general pattern of decreasing age of cooling/denudation to the NE. Combined geologic and thermochronologic data define the age and 3-D geometry of Cenozoic paleotopography that led to Grand Canyon carving. Combined AHe and AFT data indicate 2-4 km of sedimentary rocks covered the Grand Canyon region until about 40 Ma, negating the California River model. These strata were not removed from the Marble Canyon area until after about

  8. Profile of Breast Diseases in Post Pubertal Women Assessed By Clinical Breast Examination – A Community Based Study in Rural Pondicherry

    PubMed Central

    Kannan, Narayanasamy Subbaraju; Palaniappan, M.; Nandi, Partha

    2016-01-01

    Introduction Breast diseases in women, whether benign or malignant, are very commonly encountered. Benign diseases are under reported and cancer is one of the leading causes of mortality in women. This study was undertaken with an aim to study the profile of various breast disease in the community. Materials and Methods In this observational study all the post pubertal women residing in the selected village (n=1000) were included. The study was done from September 2013 to August 2015. A thorough history taking was done with the help of a predesigned proforma followed by a clinical breast examination and further investigation at our hospital if necessary. Results It was found in this study that mastalgia, both cyclical and non-cyclical as well as lumps were a common finding in the general population. Significant proportions of women were found to be in the peri-menopausal age group. Median age of menarche was 13 years; menopause was 45 years. The average age at first childbirth was 21 years with 1 year being the median duration of breast-feeding. A total of 128 women (1 in 8) had positive symptomatology with 94 (1 in 11) of them having a breast disease on examination. One was diagnosed with breast cancer. The prevalence of cyclical mastalgia was 1 in 11, non-cyclical mastalgia 1 in 34, fibroadenosis 1 in 23 and fibroadenoma 1 in 100. The awareness regarding risk factors and the availability of screening program was very poor. The average age of presentation of mastalgia was 34 years; fibroadenosis was 35 years and fibroadenoma 29 years. None of the women interacted with or had consulted a practitioner regarding mastalgia as it was not perceived to be a sign of malignancy and did not cause any significant discomfort. Conclusion It was thus concluded from this study that benign breast diseases are a common occurrence in the general population. Breast cancer continues to be diagnosed only at later stages owing to lack of awareness and inadequately structured screening

  9. 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

  10. Coming of Age in the Kisspeptin Era: Sex differences, Development, and Puberty

    PubMed Central

    Kauffman, Alexander S.

    2010-01-01

    The status of the neuroendocrine reproductive axis differs dramatically between early development, puberty, and various stages of adulthood, and also differs in several critical ways between the sexes, including its earlier pubertal activation in females than males and the presence of neural circuitry that generates preovulatory hormone surges in females but not males. The reproductive axis is controlled by various hormonal and neural pathways that converge upon forebrain gonadotropin-releasing hormone (GnRH) neurons, and many of the critical age and sex differences in the reproductive axis likely reflect differences in the “upstream” circuits and factors that regulate the GnRH system. Recently, the neural kisspeptin system has been implicated as an important regulator of GnRH neurons. Here I discuss the evidence supporting a critical role of kisspeptin signaling at different stages of life, including early postnatal and pubertal development, as well as in adulthood, focusing primarily on information gleaned from mammalian studies. I also evaluate key aspects of sexual differentiation and development of the brain as it relates to the Kiss1 system, with special emphasis on rodents. In addition to discussing recent advances in the field of kisspeptin biology, this paper will highlight a number of unanswered questions and future challenges for kisspeptin investigators, and will stress the importance of studying the kisspeptin system in both males and females, as well as in multiple species. PMID:20083160

  11. Informing school sex education using the stages of change construct: sexual behaviour and attitudes towards sexual activity and condom use of children aged 13-16 in England.

    PubMed

    Wallace, Louise M; Evers, Kerry E; Wareing, Hilary; Dunn, Orla M; Newby, Kate; Paiva, Andrea; Johnson, Janet L

    2007-01-01

    A survey of 3820 school children in England aged 13-16 years examined sexual activity using the Transtheoretical Model (TTM) Stages of Change. A quarter (26%) of teens were sexually experienced, 44.8 per cent did not use contraception and 48.9 per cent did not use condoms, every time. Past history of condom and contraceptive use, and partner willingness to use condoms were the best predictors of being in Action or Maintenance stage for condom use. Of virgins, 19.82 per cent were in Contemplation or Preparation stages for intercourse, and 85.4 per cent would use condoms every time. Sex education should be tailored to Stage, and signposting to sexual health and contraception services.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. Longitudinal changes in adolescent risk-taking: a comprehensive study of neural responses to rewards, pubertal development, and risk-taking behavior.

    PubMed

    Braams, Barbara R; van Duijvenvoorde, Anna C K; Peper, Jiska S; Crone, Eveline A

    2015-05-01

    Prior studies have highlighted adolescence as a period of increased risk-taking, which is postulated to result from an overactive reward system in the brain. Longitudinal studies are pivotal for testing these brain-behavior relations because individual slopes are more sensitive for detecting change. The aim of the current study was twofold: (1) to test patterns of age-related change (i.e., linear, quadratic, and cubic) in activity in the nucleus accumbens, a key reward region in the brain, in relation to change in puberty (self-report and testosterone levels), laboratory risk-taking and self-reported risk-taking tendency; and (2) to test whether individual differences in pubertal development and risk-taking behavior were contributors to longitudinal change in nucleus accumbens activity. We included 299 human participants at the first time point and 254 participants at the second time point, ranging between ages 8-27 years, time points were separated by a 2 year interval. Neural responses to rewards, pubertal development (self-report and testosterone levels), laboratory risk-taking (balloon analog risk task; BART), and self-reported risk-taking tendency (Behavior Inhibition System/Behavior Activation System questionnaire) were collected at both time points. The longitudinal analyses confirmed the quadratic age pattern for nucleus accumbens activity to rewards (peaking in adolescence), and the same quadratic pattern was found for laboratory risk-taking (BART). Nucleus accumbens activity change was further related to change in testosterone and self-reported reward-sensitivity (BAS Drive). Thus, this longitudinal analysis provides new insight in risk-taking and reward sensitivity in adolescence: (1) confirming an adolescent peak in nucleus accumbens activity, and (2) underlining a critical role for pubertal hormones and individual differences in risk-taking tendency.

  17. Disparities in receipt of radiotherapy and survival by age, sex and ethnicity among patients with stage I diffuse large B-cell lymphoma.

    PubMed

    Shah, Binay Kumar; Bista, Amir; Shafii, Bahman

    2015-04-01

    Disparities in cancer care have been documented. However, less is known about the disparities in diffuse large B-cell lymphoma (DLBCL). We reviewed the Surveillance, Epidemiology and End Results database to evaluate disparities in receipt of radiotherapy (RT) and relative survival among patients diagnosed with stage I DLBCL between 1998 and 2008 on the basis of age, sex and ethnicity. African Americans and other races were significantly less likely to receive RT compared to Caucasians (adjusted odds ratio [OR] of 0.743 and 0.81, respectively). Similarly, patients aged 60 + years and males were less likely to receive RT compared to their counterparts (p < 0.001). Caucasian race, younger age and female sex were associated with better survival among patients receiving RT. This study showed that 38.2% of patients with stage I DLBCL received radiotherapy. Survival rates were significantly higher for patients who received RT.

  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. Changes and tracking of fat mass in pubertal girls.

    PubMed

    Vink, Eva E; van Coeverden, Silvia C C M; van Mil, Edgar G; Felius, Bram A; van Leerdam, Frank J M; Delemarre-van de Waal, Henriëtte A

    2010-06-01

    Puberty is a critical period in body composition development. The influence of puberty on the development of fat mass asks for further investigation. We investigated the development of fat mass during puberty in a longitudinal prospective study in 152 healthy nonobese white girls, initial ages between 9 to 12 years. The influence of menarcheal age and the existing of tracking of fat mass have been analyzed. In 10 years time, participants were measured on eight time points. Various anthropometric data were collected, breast development was staged according to Tanner and body composition was determined with the dual-energy X-ray absorptiometry (DXA) scan. Calculations were made with the use of a linear mixed model. Fat mass increases from 7.9 kg (23.6%) at B1 to 18.5 kg (29.3%) at B5. Fat mass is higher in girls with an early menarche than in girls with a late menarche from B2. Girls in the quartile with initially the lowest fat mass have a chance of being in the same quartile after 10 years of 77% (P < 0.001). Girls in the quartile with initially the highest fat mass, have a risk of staying in the highest quartile of 55% (P < 0.001). Menarcheal age is of great influence on the development of fat mass. Girls with an early menarche, will have a bigger fat mass, especially at the end of puberty. Tracking of fat mass exists: a high amount of fat mass in early puberty will continue to exist at young adulthood. PMID:19875991

  20. 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.

  1. Stages of Adolescence

    MedlinePlus

    ... Español Text Size Email Print Share Stages of Adolescence Page Content Article Body Adolescence, these years from puberty to adulthood, may be roughly divided into three stages: early adolescence, generally ages eleven to fourteen; middle adolescence, ages ...

  2. 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…

  3. 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…

  4. 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…

  5. 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…

  6. Effect of simulated stages of the canine oestrous cycle on Escherichia coli binding to canine endometrium.

    PubMed

    Krekeler, N; Lodge, K M; Anderson, G A; Browning, G F; Charles, J A; Wright, P J

    2012-12-01

    Pyometra, a prevalent infectious uterine disease that affects intact middle-aged bitches, is typically associated with Escherichia coli. Our hypotheses were (i) that bacterial adhesion to canine endometrium differs between different stages of the oestrous cycle and (ii) that the adhesin FimH facilitates this adhesion. Twelve post-pubertal, ovariectomized greyhound bitches were treated with exogenous hormones to simulate different stages of the oestrous cycle. Tissue samples from each uterus were incubated with a pathogenic E. coli strain carrying the fimH gene, but no other adhesin genes (P4-wt)--or an E. coli strain in which fimH was insertionally inactivated (P4-∆fimH::kan)--or with phosphate-buffered saline as a negative control. After washing, tissue samples were homogenized for quantification of adherent bacteria. The differences in binding to canine endometrium at different stages of the oestrous cycle were not significant. However, the mean difference in binding of the P4-wt and the P4-∆fimH::kan across all stages of the simulated oestrous cycle was significant (p < 0.001 by paired t-test on geometric means). Individual differences in numbers of P4-wt bacteria bound between dogs might suggest genetic variations or epigenetic differences in FimH receptor expression by the endometrium, unrelated to the stage of the oestrous cycle. PMID:23279531

  7. 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

  8. 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

  9. 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

  10. Reliability of Schmeling's stages of ossification of medial clavicular epiphyses and its validity to assess 18 years of age in living subjects.

    PubMed

    Cameriere, R; De Luca, S; De Angelis, D; Merelli, V; Giuliodori, A; Cingolani, M; Cattaneo, C; Ferrante, L

    2012-11-01

    Nowadays, due to the global increase in migration movements, forensic age estimation of living young adults has become an important focus of interest. Minors often have no identification documents providing their correct birth dates. Establishing the age of majority is therefore fundamental in order to determine whether juvenile penal systems or penal systems in force for adults are to be applied. Radiological examination of the clavicles is one of the methods recommended by the Study Group on Forensic Age Diagnostics. In this retrospective study, a sample of chest radiographs of 274 subjects, aged between 12 and 25 years, was studied according to Schmeling's method in order to examine the ossification of both medial clavicular epiphyses. All stage classifications were evaluated by five examiners. Intra- and inter-examiner reliability was analysed by Cohen's K statistic. Intra-examiner agreement was insufficient for two of the experts. Inter-examiner agreement, among the other three operators, was moderate (K = 0.509). Study of reliability highlighted difficulties in interpretation, the need to select qualified personnel and choice of the best radiographic image in order to reduce any anatomic overlaps. Although ossification of the medial clavicular epiphyses is recommended to assess whether an individual has already reached the age of majority or not, these results suggested that it is very difficult to clearly identify the five stages of ossification by using conventional chest radiography.

  11. Effects of leaf age within growth stages of pepper and sorghum plants on leaf thickness, water, chlorophyll, and light reflectance. [in spectral vegetation discrimination

    NASA Technical Reports Server (NTRS)

    Gausman, H. W.; Cardenas, R.; Berumen, A.

    1974-01-01

    Pepper and sorghum plants (characterized by porous and compact leaf mesophylls, respectively) were used to study the influence of leaf age on light reflectance. Measurements were limited to the upper five nodal positions within each growth stage, since upper leaves make up most of the reflectance surfaces remotely sensed. The increase in leaf thickness and water content with increasing leaf age was taken into consideration, since each of these factors affects the reflectance as well as the selection of spectral wavelength intervals for optimum discrimination of vegetation.

  12. AGING AND LIFE-STAGE SUSCEPTIBILITY: TOLUENE EFFECTS ON BRAIN OXIDATIVE STRESS PARAMETERS IN BROWN NORWAY RATS.

    EPA Science Inventory

    The influence of aging on susceptibility to environmental contaminants is poorly understood. The objectives of this study were to test whether oxidative stress (OS) is a potential toxicity pathway following toluene exposure and to determine if these effects are age-dependent. We ...

  13. 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

  14. 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

  15. 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.

  16. 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

  17. DNA damage response (DDR) and senescence: shuttled inflamma-miRNAs on the stage of inflamm-aging.

    PubMed

    Olivieri, Fabiola; Albertini, Maria Cristina; Orciani, Monia; Ceka, Artan; Cricca, Monica; Procopio, Antonio Domenico; Bonafè, Massimiliano

    2015-11-01

    A major issue in aging research is how cellular phenomena affect aging at the systemic level. Emerging evidence suggests that DNA damage response (DDR) signaling is a key mechanism linking DNA damage accumulation, cell senescence, and organism aging. DDR activation in senescent cells promotes acquisition of a proinflammatory secretory phenotype (SASP), which in turn elicits DDR and SASP activation in neighboring cells, thereby creating a proinflammatory environment extending at the local and eventually the systemic level. DDR activation is triggered by genomic lesions as well as emerging bacterial and viral metagenomes. Therefore, the buildup of cells with an activated DDR probably fuels inflamm-aging and predisposes to the development of the major age-related diseases (ARDs). Micro (mi)-RNAs - non-coding RNAs involved in gene expression modulation - are released locally and systemically by a variety of shuttles (exosomes, lipoproteins, proteins) that likely affect the efficiency of their biological effects. Here we suggest that some miRNAs, previously found to be associated with inflammation and senescence - miR-146, miR-155, and miR-21 - play a central role in the interplay among DDR, cell senescence and inflamm-aging. The identification of the functions of shuttled senescence-associated miRNAs is expected to shed light on the aging process and on how to delay ARD development. PMID:26431329

  18. DNA damage response (DDR) and senescence: shuttled inflamma-miRNAs on the stage of inflamm-aging.

    PubMed

    Olivieri, Fabiola; Albertini, Maria Cristina; Orciani, Monia; Ceka, Artan; Cricca, Monica; Procopio, Antonio Domenico; Bonafè, Massimiliano

    2015-11-01

    A major issue in aging research is how cellular phenomena affect aging at the systemic level. Emerging evidence suggests that DNA damage response (DDR) signaling is a key mechanism linking DNA damage accumulation, cell senescence, and organism aging. DDR activation in senescent cells promotes acquisition of a proinflammatory secretory phenotype (SASP), which in turn elicits DDR and SASP activation in neighboring cells, thereby creating a proinflammatory environment extending at the local and eventually the systemic level. DDR activation is triggered by genomic lesions as well as emerging bacterial and viral metagenomes. Therefore, the buildup of cells with an activated DDR probably fuels inflamm-aging and predisposes to the development of the major age-related diseases (ARDs). Micro (mi)-RNAs - non-coding RNAs involved in gene expression modulation - are released locally and systemically by a variety of shuttles (exosomes, lipoproteins, proteins) that likely affect the efficiency of their biological effects. Here we suggest that some miRNAs, previously found to be associated with inflammation and senescence - miR-146, miR-155, and miR-21 - play a central role in the interplay among DDR, cell senescence and inflamm-aging. The identification of the functions of shuttled senescence-associated miRNAs is expected to shed light on the aging process and on how to delay ARD development.

  19. 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.

  20. 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

  1. An Alternative to Farmer Age as an Indicator of Life-Cycle Stage: The Case for a Farm Family Age Index

    ERIC Educational Resources Information Center

    Burton, Rob J. F.

    2006-01-01

    In studies of farming, the age of the principal decision-maker (PDM) has been associated with numerous farm structural and managerial features and has been widely accepted as a good indicator of the influence of life-cycle factors on decision-making. As such, it has become an important aspect of many quantitative studies of agricultural change.…

  2. Reproductive stage-dependent effects of additional cryoprotectant agents for the cryopreservation of stallion germ cells.

    PubMed

    Jung, Heejun; Kim, Namyoung; Yoon, Minjung

    2016-10-01

    The main objective of this study was to evaluate the efficacy of an additional cryoprotectant in 10% dimethyl sulfoxide (DMSO) on cryopreserving germ cells from stallions at different reproductive stages. Testicular samples were obtained from pre-pubertal (1-1.5 yr, n=6) and post-pubertal (3-7 yr, n=5) stallions. Germ cells were isolated using a two-enzyme digestion procedure and cryopreserved in minimal essential medium alpha containing 10% fetal bovine serum and 10% DMSO with or without addition of trehalose (50, 100, or 200mM) or polyethylene glycol (PEG, 2.5, 5, or 10%). Viability, cell population, and viable population were assessed after 1 and 3 months of cryopreservation. The viable UTF1-positive population of pre-pubertal stallion germ cells was also measured using immunocytochemistry after 1 and 3 months of cryopreservation. As expected, the viability, cell population, and viable cell population were significantly reduced after 1 and 3 months of cryopreservation. At the pre-pubertal stage, the addition of trehalose or PEG to 10% DMSO did not show any effect on the viability, cell population, viable cell population, or viable UTF1-positive germ cells at either 1 or 3 months after cryopreservation. However, at the post-pubertal stage, the viable population was significantly higher in germ cells that were cryopreserved with 5% or 10% PEG, than in the cells cryopreserved with 10% DMSO only. In conclusion, PEG at 5% or 10% added to 10% DMSO serves as an optimal cryoprotectant agent for the cryopreservation of germ cells from post-pubertal stallions. PMID:27546795

  3. Age, gender, and puberty influence the development of facial emotion recognition.

    PubMed

    Lawrence, Kate; Campbell, Ruth; Skuse, David

    2015-01-01

    Our ability to differentiate between simple facial expressions of emotion develops between infancy and early adulthood, yet few studies have explored the developmental trajectory of emotion recognition using a single methodology across a wide age-range. We investigated the development of emotion recognition abilities through childhood and adolescence, testing the hypothesis that children's ability to recognize simple emotions is modulated by chronological age, pubertal stage and gender. In order to establish norms, we assessed 478 children aged 6-16 years, using the Ekman-Friesen Pictures of Facial Affect. We then modeled these cross-sectional data in terms of competence in accurate recognition of the six emotions studied, when the positive correlation between emotion recognition and IQ was controlled. Significant linear trends were seen in children's ability to recognize facial expressions of happiness, surprise, fear, and disgust; there was improvement with increasing age. In contrast, for sad and angry expressions there is little or no change in accuracy over the age range 6-16 years; near-adult levels of competence are established by middle-childhood. In a sampled subset, pubertal status influenced the ability to recognize facial expressions of disgust and anger; there was an increase in competence from mid to late puberty, which occurred independently of age. A small female advantage was found in the recognition of some facial expressions. The normative data provided in this study will aid clinicians and researchers in assessing the emotion recognition abilities of children and will facilitate the identification of abnormalities in a skill that is often impaired in neurodevelopmental disorders. If emotion recognition abilities are a good model with which to understand adolescent development, then these results could have implications for the education, mental health provision and legal treatment of teenagers. PMID:26136697

  4. Age, gender, and puberty influence the development of facial emotion recognition

    PubMed Central

    Lawrence, Kate; Campbell, Ruth; Skuse, David

    2015-01-01

    Our ability to differentiate between simple facial expressions of emotion develops between infancy and early adulthood, yet few studies have explored the developmental trajectory of emotion recognition using a single methodology across a wide age-range. We investigated the development of emotion recognition abilities through childhood and adolescence, testing the hypothesis that children’s ability to recognize simple emotions is modulated by chronological age, pubertal stage and gender. In order to establish norms, we assessed 478 children aged 6–16 years, using the Ekman-Friesen Pictures of Facial Affect. We then modeled these cross-sectional data in terms of competence in accurate recognition of the six emotions studied, when the positive correlation between emotion recognition and IQ was controlled. Significant linear trends were seen in children’s ability to recognize facial expressions of happiness, surprise, fear, and disgust; there was improvement with increasing age. In contrast, for sad and angry expressions there is little or no change in accuracy over the age range 6–16 years; near-adult levels of competence are established by middle-childhood. In a sampled subset, pubertal status influenced the ability to recognize facial expressions of disgust and anger; there was an increase in competence from mid to late puberty, which occurred independently of age. A small female advantage was found in the recognition of some facial expressions. The normative data provided in this study will aid clinicians and researchers in assessing the emotion recognition abilities of children and will facilitate the identification of abnormalities in a skill that is often impaired in neurodevelopmental disorders. If emotion recognition abilities are a good model with which to understand adolescent development, then these results could have implications for the education, mental health provision and legal treatment of teenagers. PMID:26136697

  5. A Reevaluation of the Question: Is the Pubertal Resurgence in Pulsatile GnRH Release in the Male Rhesus Monkey (Macaca mulatta) Associated With a Gonad-Independent Augmentation of GH Secretion?

    PubMed

    Shahab, M; Trujillo, M Vargas; Plant, T M

    2015-10-01

    A somatic signal has been posited to trigger the pubertal resurgence in pulsatile GnRH secretion that initiates puberty in highly evolved primates. That GH might provide such a signal emerged in 2000 as a result of a study reporting that circulating nocturnal GH concentrations in castrated juvenile male monkeys increased in a 3-week period immediately preceding the pubertal resurgence of LH secretion. The present study was conducted to reexamine this intriguing relationship, again in an agonadal model. Four castrated juvenile male monkeys were implanted with indwelling jugular catheters, housed in remote sampling cages, and subjected to 24 hours of sequential blood sampling (every 30 min) every 2 weeks from 19.5 to 22 months of age. Twenty-four-hour profiles of circulating GH concentrations were analyzed using the pulse detection algorithm, PULSAR, and developmental changes in pulsatile GH release with respect to the initiation of the pubertal rise of LH secretion (week 0; observed between 22.5 and 32 mo of age) were examined for significance by a repeated-measures ANOVA. Changes in the parameters of pulsatile GH secretion, including mean 24-hour GH concentration and GH pulse frequency and pulse amplitude for 3 (n = 4) and 6 (n = 3) months before week 0 were unremarkable and nonsignificant. These findings fail to confirm those of the earlier study and lead us to conclude that the timing of the pubertal resurgence of GnRH release in the male monkey is not dictated by GH. Reasons for the discrepancy between the two studies are unclear. PMID:26181107

  6. 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…

  7. 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…

  8. 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…

  9. 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…

  10. 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.

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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…

  16. 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…

  17. 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…

  18. 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…

  19. 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...

  20. 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

  1. 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…

  2. 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…

  3. 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…

  4. 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…

  5. 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.

  6. 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...

  7. 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…

  8. 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…

  9. Young and Middle-Aged Rats Exhibit Isometric Forelimb Force Control Deficits in a Model of Early-Stage Parkinson's disease

    PubMed Central

    Bethel-Brown, Crystal S.; Morris, Jill K.; Stanford, John A.

    2011-01-01

    Deficits in manual motor control often accompany the early stages of Parkinson’s disease (PD), and are often revealed through isometric force tasks. In order to determine whether similar deficits occur in a rat model of early-stage PD, young (8 months) and middle-aged (18 months) rats were trained to produce sustained press-hold-release isometric forelimb responses that allowed for analyses of force output and spectral analysis of forelimb stability and tremor. Rats then received a 6-hydroxydopamine (6-OHDA) infusion into the striatum contralateral to the trained forelimb and were tested for four weeks post-lesion. The resulting partial striatal dopamine depletions (which at 41 ± 12% and 43 ± 6% in young and middle-aged rats, respectively, did not differ between the two groups) resulted in isometric forelimb deficits. Specifically, rats exhibited significantly diminished force stability and increased high frequency (10–25 Hz) tremor, indicating potential postural disturbances and increased postural tremor respectively. Durations of press-hold-release bouts were also increased post-lesion, suggesting difficulty in task disengagement. Despite pre-lesion differences in some of the force measures, the effects of partial nigrostriatal DA depletion did not differ between the two age groups. These results support the use of the press-while-licking task in preclinical studies modeling isometric force control deficits in PD. PMID:21767573

  10. Advanced maternal age and the risk of Down syndrome characterized by the meiotic stage of the chromosomal error: A population-based study

    SciTech Connect

    Yoon, P.W.; Khoury, M.J.; Freeman, S.B.

    1996-03-01

    The identification of DNA polymorphisms makes it possible to classify trisomy 21 according to the parental origin and stage (meiosis I [MI], meiosis II [MII], or postzygotic mitotic) of the chromosomal error. Studying the effect of parental age on these subgroups could shed light on parental exposures and their timing. From 1989 through 1993, 170 infants with trisomy 21 and 267 randomly selected control infants were ascertained in a population-based, case-control study in metropolitan Atlanta. Blood samples for genetic studies were obtained from case infants and their parents. Using logistic regression, we independently examined the association between maternal and paternal age and subgroups of trisomy 21 defined by parental origin and meiotic stage. The distribution of trisomy 21 by origin was 86% maternal (75% MI and 25% MII), 9% paternal (50% MI and 50% MII), and 5% mitotic. Compared with women <25 years of age, women {>=}40 years old had an odds ratio of 5.2 (95% confidence interval, 1.0-27.4) for maternal MI (MMI) errors and 51.4 (95% confidence interval, 2.3-999.0) for maternal MII (MMII) errors. Birth-prevalence rates for women {>=}40 years old were 4.2/1,000 births for MMI errors and 1.9/1,000 births for MMII errors. These results support an association between advanced maternal age and both MMI and MMII errors. The association with MI does not pinpoint the timing of the error; however, the association with MII implies that there is at least one maternal age-related mechanism acting around the time of conception. 16 refs., 1 fig., 2 tabs.

  11. 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

  12. 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

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

    PubMed Central

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

    2016-01-01

    Background Birth order has been proposed as a cardiovascular risk factor, because the lower birth weight and greater infant weight gain typical of firstborns could programme metabolism detrimentally. Methods We examined the associations of birth order (firstborn or laterborn) with birth weight-for-gestational age, length/height and body mass index (BMI) z-scores during infancy, childhood, and puberty using generalized estimating equations, with age at pubertal onset using interval-censored regression and with age-, sex- and height-standardized blood pressure, height and BMI z-scores at 13 years using linear regression in a population-representative Chinese birth cohort: “Children of 1997” (n = 8,327). Results Compared with laterborns, firstborns had lower birth weight-for-gestational age (mean difference = -0.18 z-score, 95% confidence interval (CI) -0.23, -0.14), lower infant BMI (-0.09 z-score, 95% CI -0.14, -0.04), greater childhood height (0.10 z-score, 95% CI 0.05, 0.14) and BMI (0.08 z-score, 95% CI 0.03, 0.14), but not greater pubertal BMI (0.05 z-score, 95% CI -0.02, 0.11), adjusted for sex, parental age, birthplace, education and income. Firstborns had earlier onset of pubic hair (time ratio = 0.988, 95% CI 0.980, 0.996), but not breast or genitalia, development. Firstborns had greater BMI (0.07 z-score, 95% CI 0.002, 0.15), but not height (0.05 z-score, 95% CI -0.01, 0.11), at 13 years, but similar blood pressure. Conclusions Differences by birth order continue into early adolescence with firstborns being heavier with earlier pubic hair development, which could indicate long-term cardiovascular risk. PMID:27088360

  14. Age of thelarche and menarche in contemporary US females: a cross-sectional analysis

    PubMed Central

    Cabrera, Susanne M.; Bright, George M.; Frane, James W.; Blethen, Sandra L.

    2014-01-01

    Aim A recent secular trend towards earlier thelarche has been suggested. The aim of this study is to examine normative ages of thelarche and menarche in contemporary US females. Methods Trained physicians documented Tanner breast stage by observation in a cross-sectional cohort. Age of menarche was self-reported. The subjects were healthy female children and adolescents. The mean age of thelarche was determined by probit analysis and the mean age of menarche was determined by using a normal time-to-event model. Results Mean age of thelarche was 9.7 years among 610 females aged 3.0–17.9 years (70% non-Hispanic Caucasian (NHC), 14% African-Americans, 7% Hispanic, 9% “other”). The mean age of menarche was 12.8 years for NHC, with African-Americans having menarche 0.6 years earlier. Conclusions Thelarche occurred earlier than recently reported, while age of menarche remained unchanged, this supported a persistent secular trend towards earlier thelarche but stable age of menarche. This suggests that the observed thelarche is gonadotropin-independent or the tempo of pubertal advancement has slowed. PMID:23959659

  15. Factors Associated with Blood Culture Contamination in the Emergency Department: Critical Illness, End-Stage Renal Disease, and Old Age

    PubMed Central

    Chang, Chih-Jan; Wu, Chi-Jung; Hsu, Hsiang-Chin; Wu, Chiu-Hui; Shih, Fang-Ying; Wang, Shou-Wen; Wu, Yi-Hui; Chang, Chia-Ming; Tu, Yi-Fang; Chi, Chih-Hsien; Shih, Hsin-I

    2015-01-01

    Background Blood culture contamination in emergency departments (ED) that experience a high volume of patients has negative impacts on optimal patient care. It is therefore important to identify risk factors associated with blood culture contamination in EDs. Methodology/Principal Findings A prospectively observational study in a university-affiliated hospital were conducted between August 2011 and December 2012. Positive monomicrobial and negative blood cultures drawn from adult patients in the ED were analyzed to evaluate the possible risk factors for contamination. A total of 1,148 positive monomicrobial cases, 391 contamination cases, and 13,689 cases of negative blood culture were identified. Compared to patients with negative blood cultures, patients in triage levels 1 and 2 (Incidence Rate Ratio, IRR = 2.24), patients with end-stage renal disease (ESRD) (IRR = 2.05), and older patients (IRR: 1.02 per year) were more likely to be associated with ED blood culture contamination. Conclusions/Significance Critical patients (triage levels 1 and 2), ESRD patients, and older patients were more commonly associated with blood culture contamination in the ED. Further studies to evaluate whether the characteristics of skin commensals contribute to blood culture contamination is warranted, especially in hospitals populated with high-risk patients. PMID:26448628

  16. Nature and Age of Neighbours Matter: Interspecific Associations among Tree Species Exist and Vary across Life Stages in Tropical Forests.

    PubMed

    Ledo, Alicia

    2015-01-01

    Detailed information about interspecific spatial associations among tropical tree species is scarce, and hence the ecological importance of those associations may have been underestimated. However, they can play a role in community assembly and species diversity maintenance. This study investigated the spatial dependence between pairs of species. First, the spatial associations (spatial attraction and spatial repulsion) that arose between species were examined. Second, different sizes of trees were considered in order to evaluate whether the spatial relationships between species are constant or vary during the lifetime of individuals. Third, the consistency of those spatial associations with the species-habitat associations found in previous studies was assessed. Two different tropical ecosystems were investigated: a montane cloud forest and a lowland moist forest. The results showed that spatial associations among species exist, and these vary among life stages and species. The rarity of negative spatial interactions suggested that exclusive competition was not common in the studied forests. On the other hand, positive interactions were common, and the results of this study strongly suggested that habitat associations were not the only cause of spatial attraction among species. If this is true, habitat associations and density dependence are not the only mechanisms that explain species distribution and diversity; other ecological interactions, such as facilitation among species, may also play a role. These spatial associations could be important in the assembly of tropical tree communities and forest succession, and should be taken into account in future studies. PMID:26581110

  17. Nature and Age of Neighbours Matter: Interspecific Associations among Tree Species Exist and Vary across Life Stages in Tropical Forests.

    PubMed

    Ledo, Alicia

    2015-01-01

    Detailed information about interspecific spatial associations among tropical tree species is scarce, and hence the ecological importance of those associations may have been underestimated. However, they can play a role in community assembly and species diversity maintenance. This study investigated the spatial dependence between pairs of species. First, the spatial associations (spatial attraction and spatial repulsion) that arose between species were examined. Second, different sizes of trees were considered in order to evaluate whether the spatial relationships between species are constant or vary during the lifetime of individuals. Third, the consistency of those spatial associations with the species-habitat associations found in previous studies was assessed. Two different tropical ecosystems were investigated: a montane cloud forest and a lowland moist forest. The results showed that spatial associations among species exist, and these vary among life stages and species. The rarity of negative spatial interactions suggested that exclusive competition was not common in the studied forests. On the other hand, positive interactions were common, and the results of this study strongly suggested that habitat associations were not the only cause of spatial attraction among species. If this is true, habitat associations and density dependence are not the only mechanisms that explain species distribution and diversity; other ecological interactions, such as facilitation among species, may also play a role. These spatial associations could be important in the assembly of tropical tree communities and forest succession, and should be taken into account in future studies.

  18. Nature and Age of Neighbours Matter: Interspecific Associations among Tree Species Exist and Vary across Life Stages in Tropical Forests

    PubMed Central

    Ledo, Alicia

    2015-01-01

    Detailed information about interspecific spatial associations among tropical tree species is scarce, and hence the ecological importance of those associations may have been underestimated. However, they can play a role in community assembly and species diversity maintenance. This study investigated the spatial dependence between pairs of species. First, the spatial associations (spatial attraction and spatial repulsion) that arose between species were examined. Second, different sizes of trees were considered in order to evaluate whether the spatial relationships between species are constant or vary during the lifetime of individuals. Third, the consistency of those spatial associations with the species-habitat associations found in previous studies was assessed. Two different tropical ecosystems were investigated: a montane cloud forest and a lowland moist forest. The results showed that spatial associations among species exist, and these vary among life stages and species. The rarity of negative spatial interactions suggested that exclusive competition was not common in the studied forests. On the other hand, positive interactions were common, and the results of this study strongly suggested that habitat associations were not the only cause of spatial attraction among species. If this is true, habitat associations and density dependence are not the only mechanisms that explain species distribution and diversity; other ecological interactions, such as facilitation among species, may also play a role. These spatial associations could be important in the assembly of tropical tree communities and forest succession, and should be taken into account in future studies. PMID:26581110

  19. Improving quality of life in patients with end-stage age-related macular degeneration: focus on miniature ocular implants.

    PubMed

    Singer, Michael A; Amir, Nancy; Herro, Angela; Porbandarwalla, Salman S; Pollard, Joseph

    2012-01-01

    Low vision devices in the past have been mainly extraocular. There are now four new devices in different stages of development and implementation that are currently available. Three of them, the Implantable Miniature Telescope (IMT, VisionCare Ophthalmic Technologies, Saratoga, CA), Intraocular Lens for Visually Impaired People (IOL-VIP, IOL-VIP System, Soleko, Pontecorvo, Italy), and Lipschitz Mirror Implant (LMI, Optolight Vision Technology, Herzlia, Israel) are implanted into the anterior segment while the Argus II (Second Sight Medical Products, Sylmar, CA) is implanted into the posterior segment. The goal of these devices is to increase the patient quality of life which has been measured by Visual Functioning Questionnaire (VFQ) scales. The IMT is the only device that has been shown to increase the VFQ score by seven points at 6 months compared to baseline. It is the only FDA-approved device in the US while the Argus has been approved in Europe. Each of these prosthetics has potential benefits for patients.

  20. 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

  1. Effect of Advancing Age and Multiple Chronic Conditions on Mortality in Patients with End-Stage Renal Disease after Implantable Cardioverter-Defibrillator Placement

    PubMed Central

    Krishnaswami, Ashok; Kiley, Mary-Lou; Anthony, Faith F; Chen, Yuexin; Chen, Jason; Rajagopal, Sumanth; Liu, Taylor I; Young, Charlie; Paxton, Elizabeth W

    2016-01-01

    Context: There is insufficient information on the effect that advancing age and multiple chronic conditions (MCC) have on mortality after placement of an implantable cardioverter-defibrillator in patients with end-stage renal disease (ESRD) vs non-ESRD. Objective: To assess whether a differential effect of age and MCC exists between ESRD and non-ESRD. Design: Population-based, retrospective cohort study using data from the national Kaiser Permanente Cardiac Device Registry of patients who underwent placement of an implantable cardioverter-defibrillator between January 1, 2007, and December 31, 2013. Main Outcome Measures: All-cause mortality. Results: Of 7825 patients with implantable cardioverter-defibrillator placement, ESRD-affected patients constituted 4.0% of the cohort (n = 311), were similar in age (p = 0.91), and presented with a larger comorbidity burden (3.3 ± 1.3 vs 2.4 ± 1.5, p < 0.001). The effect of advancing age (every 5 years) on mortality in the ESRD cohort (hazard ratio [HR] = 1.11, 95% confidence interval [CI] = 1.03–1.20) was less than in the non-ESRD cohort (HR = 1.28, 95% CI = 1.25–1.32). Similarly, the effect of each additional comorbidity in the ESRD cohort was less (HR = 1.04, 95% CI = 0.91–1.19) than in the non-ESRD group (HR = 1.20, 95% CI = 1.16–1.25). Lastly, ESRD was independently associated with a 3-fold greater hazard of mortality. Conclusions: Advancing age and increasing number of MCC have a differential effect on mortality risk in patients with ESRD compared with their non-ESRD counterparts. Future studies should focus on assessment of nonlinear relationships of age, MCC, and naturally occurring clusters of MCC on mortality. PMID:26562307

  2. [Neuromuscular status of children of different gestational age on the stage of transition from intrauterine immersion to the earth's gravity].

    PubMed

    2012-01-01

    The work was aimed at describing the neuromuscular status of premature baby in the context of the ontogenetic and zero gravity model using the results of superficial interference electromyography (IEMG). Throughout six postnatal weeks, IEMG of premature babies is similar to EMG of full-term child on the first days of extrauterine life; IEMG is characterized by a "simplified" temporal structure, low amplitude and frequency, IEMG dynamics of fullterm child is slow in contrast to premature baby; the reason seems to be maximum long intrauterine life during which the motor system gets better prepared and maturates. On the other hand, complexity and high amplitude of premature baby IEMG as compared with full-term child of the same postconceptual age are associated with the inevitable sensory stimulation after birth. Abilitation procedures provided to premature baby could be adapted to the purposes of post-flight rehabilitation of cosmonauts.

  3. 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 ...

  4. Copper and zinc concentrations in 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, Abulfazl; Tahmasebian, Hamid

    2015-01-01

    To investigate uterine fluid and serum copper (Cu) and zinc (Zn) variations during the estrous cycle in water buffaloes, 71 genital tracts and blood samples were collected from the abattoir in Urmia, Iran. The phase of the estrous cycle was determined by examining ovarian structures; 18, 15, 16 and 22 were pro-estrous, estrous, met-estrous and diestrous, respectively. 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 (77.10 ± 1.50 µg dL(-1)) and uterine fluid (296.40 ± 9.40 μg dL(-1)) Cu in cyclic cows was higher than the values of 54.00 ± 1.10 μg dL(-1) and 133.40 ± 5.70 μg dL(-1) in pre-pubertal calves, respectively. Blood serum (114.60 ± 3.20 μg dL(-1)) and the uterine fluid (349.90 ± 8.90 μg dL(-1)) Zn content in cyclic cows were also higher than those (98.80 ± 1.50 μg dL(-1) and 246.6 ± 4.50 μg dL(-1) respectively) in pre-pubertal calves. Serum Cu in pro-estrus and estrus were lower than those in other stages and also lower than those in the uterine fluid. The lowest serum Zn content was recorded in pro- and met-estrus, while in the uterine fluid it was observed in estrus. In all stages of estrous cycle the uterine fluid Zn content was significantly higher than those of the serum. These results suggested that during the estrous cycle in the buffalo cows, Cu and Zn were actively secreted in uterine lumen and were not dependent on blood serum. The values also increased after puberty.

  5. Copper and zinc concentrations in uterine fluid and blood serum during the estrous cycle and pre-pubertal phase in water buffaloes

    PubMed Central

    Alavi Shoushtari, Sayed Mortaza; Asri Rezaie, Siamak; Khaki, Amir; Belbasi, Abulfazl; Tahmasebian, Hamid

    2015-01-01

    To investigate uterine fluid and serum copper (Cu) and zinc (Zn) variations during the estrous cycle in water buffaloes, 71 genital tracts and blood samples were collected from the abattoir in Urmia, Iran. The phase of the estrous cycle was determined by examining ovarian structures; 18, 15, 16 and 22 were pro-estrous, estrous, met-estrous and diestrous, respectively. 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 (77.10 ± 1.50 µg dL-1) and uterine fluid (296.40 ± 9.40 μg dL-1) Cu in cyclic cows was higher than the values of 54.00 ± 1.10 μg dL-1 and 133.40 ± 5.70 μg dL-1 in pre-pubertal calves, respectively. Blood serum (114.60 ± 3.20 μg dL-1) and the uterine fluid (349.90 ± 8.90 μg dL-1) Zn content in cyclic cows were also higher than those (98.80 ± 1.50 μg dL-1 and 246.6 ± 4.50 μg dL-1 respectively) in pre-pubertal calves. Serum Cu in pro-estrus and estrus were lower than those in other stages and also lower than those in the uterine fluid. The lowest serum Zn content was recorded in pro- and met-estrus, while in the uterine fluid it was observed in estrus. In all stages of estrous cycle the uterine fluid Zn content was significantly higher than those of the serum. These results suggested that during the estrous cycle in the buffalo cows, Cu and Zn were actively secreted in uterine lumen and were not dependent on blood serum. The values also increased after puberty. PMID:26893810

  6. Copper and zinc concentrations in 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, Abulfazl; Tahmasebian, Hamid

    2015-01-01

    To investigate uterine fluid and serum copper (Cu) and zinc (Zn) variations during the estrous cycle in water buffaloes, 71 genital tracts and blood samples were collected from the abattoir in Urmia, Iran. The phase of the estrous cycle was determined by examining ovarian structures; 18, 15, 16 and 22 were pro-estrous, estrous, met-estrous and diestrous, respectively. 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 (77.10 ± 1.50 µg dL(-1)) and uterine fluid (296.40 ± 9.40 μg dL(-1)) Cu in cyclic cows was higher than the values of 54.00 ± 1.10 μg dL(-1) and 133.40 ± 5.70 μg dL(-1) in pre-pubertal calves, respectively. Blood serum (114.60 ± 3.20 μg dL(-1)) and the uterine fluid (349.90 ± 8.90 μg dL(-1)) Zn content in cyclic cows were also higher than those (98.80 ± 1.50 μg dL(-1) and 246.6 ± 4.50 μg dL(-1) respectively) in pre-pubertal calves. Serum Cu in pro-estrus and estrus were lower than those in other stages and also lower than those in the uterine fluid. The lowest serum Zn content was recorded in pro- and met-estrus, while in the uterine fluid it was observed in estrus. In all stages of estrous cycle the uterine fluid Zn content was significantly higher than those of the serum. These results suggested that during the estrous cycle in the buffalo cows, Cu and Zn were actively secreted in uterine lumen and were not dependent on blood serum. The values also increased after puberty. PMID:26893810

  7. Highly retentive core domains in K-feldspar preserve argon ages from high temperature stages of granite exhumation

    NASA Astrophysics Data System (ADS)

    Forster, Marnie; Lister, Gordon

    2016-04-01

    Retentive core domains are characterized by diffusion parameters that imply K-feldspar should be able to retain argon even at temperatures near or above the granite solidus. In this case it should be possible to date granite emplacement using argon geochronology, and the same answer should be obtained as by using other methods. We present one case study where this is the case, from the elevated Capoas granite stock on Palawan, in the Philippines, and another where it is not, from the South Cyclades Shear Zone, on Ios, Greece. We attempt to determine the factors such as the role of fluid ingress in triggering the in situ recrystallization that can eliminate and/or modify the core domains, leading to relatively youthful ages. Thermochronology is still possible, because less retentive diffusion domains exist, but different methods need to be applied to interpret the data. The work also demonstrates that K-feldspar can be sufficiently retentive as to allow direct dating of processes that reduce the dimensions of diffusion domains, e.g., cataclased and/or recrystallized K-feldspar in fault rock and/or mylonite. These are important developments in the methodology of 40Ar/39Ar geochronology, but to further advance we need to clarify the nature of these highly retentive core domains. In particular, we need better understand how they are modified by microstructural processes during deformation and metamorphism. We need also to assess the role of any crystal structural changes during step-heating in vacuo.

  8. Regarding the real diversity of Glyptodontidae (Mammalia, Xenarthra) in the late Pliocene (Chapadmalalan Age/Stage) of Argentina.

    PubMed

    Zurita, Alfredo E; Taglioretti, Matías; DE Los Reyes, Martín; Cuadrelli, Francisco; Poire, Daniel

    2016-06-01

    A large diversity of Glyptodontidae has been proposed as characterizing the Chapadmalalan Age (Pliocene). Most of these taxa were recognized on the basis of partial dorsal carapaces and/or caudal tubes, whereas the main diagnostic characteristic is a particular morphology of the exposed surface of the osteoderms. From a biostratigraphic point of view some species are biostratigraphically important. The Upper Chapadmalalan is based on the Paraglyptodon chapadmalensis biozone. Both the re-evaluation of the type and referred materials and new significant findings from the Chapadmalal and El Polvorín Formations indicate that the diversity of Pliocene Glyptodontidae is more limited than previously supposed. The particular morphology of the exposed surface of the osteoderms that characterizes some of the species actually corresponds to a taphonomic alteration, which results in a non-real ornamentation pattern. Thus, the Glyptodontinae P. chapadmalensis must be replaced as a fossil guide because neither this species nor the species included in the genera Urotherium, Trachycalyptus and Lomaphorus are well characterized. Taking into account the diversity of Glyptodontidae for this lapse, the Glyptodontinae are very scarce (a situation that contrasts with its records in the Pleistocene), whereas Eosclerocalyptus, "Plohophorini" (Plohophorus) and Doedicurinae (cf. Eleutherocercus antiquus) are among the most recorded taxa. PMID:27276376

  9. Regarding the real diversity of Glyptodontidae (Mammalia, Xenarthra) in the late Pliocene (Chapadmalalan Age/Stage) of Argentina.

    PubMed

    Zurita, Alfredo E; Taglioretti, Matías; DE Los Reyes, Martín; Cuadrelli, Francisco; Poire, Daniel

    2016-06-01

    A large diversity of Glyptodontidae has been proposed as characterizing the Chapadmalalan Age (Pliocene). Most of these taxa were recognized on the basis of partial dorsal carapaces and/or caudal tubes, whereas the main diagnostic characteristic is a particular morphology of the exposed surface of the osteoderms. From a biostratigraphic point of view some species are biostratigraphically important. The Upper Chapadmalalan is based on the Paraglyptodon chapadmalensis biozone. Both the re-evaluation of the type and referred materials and new significant findings from the Chapadmalal and El Polvorín Formations indicate that the diversity of Pliocene Glyptodontidae is more limited than previously supposed. The particular morphology of the exposed surface of the osteoderms that characterizes some of the species actually corresponds to a taphonomic alteration, which results in a non-real ornamentation pattern. Thus, the Glyptodontinae P. chapadmalensis must be replaced as a fossil guide because neither this species nor the species included in the genera Urotherium, Trachycalyptus and Lomaphorus are well characterized. Taking into account the diversity of Glyptodontidae for this lapse, the Glyptodontinae are very scarce (a situation that contrasts with its records in the Pleistocene), whereas Eosclerocalyptus, "Plohophorini" (Plohophorus) and Doedicurinae (cf. Eleutherocercus antiquus) are among the most recorded taxa.

  10. Treatment of early-stage human epidermal growth factor 2-positive cancers among medicare enrollees: age and race strongly associated with non-use of trastuzumab.

    PubMed

    Vaz-Luis, Ines; Lin, Nancy U; Keating, Nancy L; Barry, William T; Lii, Joyce; Burstein, Harold J; Winer, Eric P; Freedman, Rachel A

    2016-08-01

    Adjuvant trastuzumab for human epidermal growth factor receptor-2 (HER2)-positive breast cancer is highly efficacious regardless of age. Recent data suggested that many older patients with HER2-positive disease do not receive adjuvant trastuzumab. Nevertheless, some of this 'under-treatment' may be clinically appropriate. We used Surveillance, Epidemiology and End Results (SEER)-Medicare data to identify patients aged ≥ 66 with stage ≥ Ib-III, HER2-positive breast cancer diagnosed during 2010-2011 (HER2 status available) who did not have a history of congestive heart failure. We described all systemic treatments received and sociodemographic and clinical characteristics associated with treatment patterns. Among 770 women 44.4 % did not receive trastuzumab, including 21.8 % who received endocrine therapy only, 6.3 % who received chemotherapy (±endocrine therapy) and 16.2 % who did not receive any systemic therapy. In addition to age and grade, race was strongly associated with non-use of trastuzumab (64.4 % of Non-Hispanic blacks vs. 43.6 % of whites did not receive trastuzumab, adjusted ORNon-Hispanic black vs. white = 3.14, 95 %CI = 1.38-7.17), and many patients with stage III disease did not receive trastuzumab. Further, 16.2 % of patients did not receive any systemic treatment and this occurred more frequently for black patients. Over 40 % of older patients with indication to receive adjuvant trastuzumab did not receive it and nearly 20 % of these patients did not receive any other treatment. Although treatment omission may be appropriate in some cases, we observed concerning differences in trastuzumab receipt, particularly for black women. Strategies to optimize care for older patients and to eliminate treatment disparities are urgently needed. PMID:27484879

  11. Age at Puberty and Father Absence in a National Probability Sample

    ERIC Educational Resources Information Center

    Bogaert, A.F.

    2005-01-01

    The relations between intactness of the parental unit (e.g., father absent at age 14) and pubertal timing in both men and women were examined in a US national probability sample. In both men and women, an absent father at age 14 predicted an earlier age of puberty (e.g., early menarche or voice change). There was little evidence that an absent…

  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. Atlantic Ocean Circulation During the Last Ice Age: A 231Pa/230Th Record of Marine Isotope Stage 3

    NASA Astrophysics Data System (ADS)

    Major, C. O.; McManus, J. F.; Keigwin, L. D.; Francois, R.; Brown-Leger, S.

    2005-12-01

    Millennial-scale oscillations in climate-sensitive geochemical proxies are seen throughout Marine Isotope Stage 3 (MIS3, ~30 to 60 ka BP) in marine and ice-core records, with variability nearly as large as that seen on the last deglaciation. Nutrient proxies, such as δ13C, have been widely used to reconstruct water mass reorganizations associated with this so-called stadial-interstadial variability. While such passive tracers are invaluable in determining the configuration of water masses they cannot provide direct information about the rate of thermohaline circulation. The burial ratio of unsupported 231Pa:230Th in bulk North Atlantic sediments is a function of the residence time of water in this basin, and thus serves as a dynamical proxy sensitive to the vigor of thermohaline circulation and an important complement to passive proxies. We present a suite of data, including 231Pa/230Th, 230Th-normalized fluxes, and stable isotopes, from the Blake Outer Ridge (BOR) (core KNR140-8JPC, ~3400 m), a drift deposit underlying the deep western boundary current in the subtropical north Atlantic. 231Pa/230Th data indicate moderate-amplitude millennial-scale variations in circulation rate during MIS3. 231Pa/230Th ranges between maximum values less than the production rate ratio (0.093) and minimum values close to the core-top ratio (~0.058), with high and low ratios associated with stadials and interstadials, respectively. These data indicate continuous but on average less vigorous ventilation of the western basin compared to present, with substantially reduced circulation during stadials. Heinrich events during MIS3 do not appear to be associated with the particularly dramatic drop in circulation rate seen in the deglacial H1 interval on the Bermuda Rise (McManus et al., 2004). 230Th-normalized fluxes account for only 10 to 50 percent of the total mass accumulation, indicating significant sediment focusing at this site particularly during the stadials. Benthic δ18O from

  14. 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

  15. Natural growth and diet of known-age pallid sturgeon (Scaphirhynchus albus) early life stages in the upper Missouri River basin, Montana and North Dakota

    USGS Publications Warehouse

    Braaten, P.J.; Fuller, D.B.; Lott, R.D.; Haddix, T.M.; Holte, L.D.; Wilson, R.H.; Bartron, M.L.; Kalie, J.A.; DeHaan, P.W.; Ardren, W.R.; Holm, R.J.; Jaeger, M.E.

    2012-01-01

    Prior to anthropogenic modifications, the historic Missouri River provided ecological conditions suitable for reproduction, growth, and survival of pallid sturgeon Scaphirhynchus albus. However, little information is available to discern whether altered conditions in the contemporary Missouri River are suitable for feeding, growth and survival of endangered pallid sturgeon during the early life stages. In 2004 and 2007, nearly 600 000 pallid sturgeon free embryos and larvae were released in the upper Missouri River and survivors from these releases were collected during 2004–2010 to quantify natural growth rates and diet composition. Based on genetic analysis and known-age at release (1–17 days post-hatch, dph), age at capture (dph, years) could be determined for each survivor. Totals of 23 and 28 survivors from the 2004 and 2007 releases, respectively, were sampled. Growth of pallid sturgeon was rapid (1.91 mm day-1) during the initial 13–48 dph, then slowed as fish approached maximum length (120–140 mm) towards the end of the first growing season. The diet of young-of-year pallid sturgeon was comprised of Diptera larvae, Diptera pupae, and Ephemeroptera nymphs. Growth of pallid sturgeon from ages 1–6 years was about 48.0 mm year-1. This study provides the first assessment of natural growth and diet of young pallid sturgeon in the wild. Results depict pallid sturgeon growth trajectories that may be expected for naturally produced wild stocks under contemporary habitat conditions in the Missouri River and Yellowstone River.

  16. Late-Stage HIMU-Type Volcanism on the Walvis Ridge: Not just Part of an Age-Progressive Tristan-Gough Hotspot Track

    NASA Astrophysics Data System (ADS)

    Homrighausen, S.; Hoernle, K.; Hauff, F.; Portnyagin, M.; Werner, R.; Geldmacher, J.; Garbe-Schoenberg, C. D.

    2015-12-01

    The Walvis Ridge forms the NE portion of the Tristan-Gough hotspot track. It links the Etendeka large igneous province (LIP) in Africa, initially connected to the Parana LIP in South America, to the Guyot Province, that ends at the active volcanic islands of Tristan da Cunha and Gough. After the plume head stage, the hotspot changed from a ridge-centered plume tail, forming the Walvis Ridge and Rio Grande Rise (130-60 Ma), to an intraplate setting resulting in the geochemical distinct Tristan and Gough subtracks (Rohde et al. 2013; Geology 41). New major and trace element and radiogenic isotope data have been generated from 36 new dredge locations on the Walvis Ridge during R/V Sonne cruises SO233 and SO234. Based on the bathymetric data, we have identified tectonic structures and subsidence rates which indicate a complex geodynamic interplay of the Walvis Ridge formation and westward migration of the Mid Atlantic Ridge and the Rio Grande Rise. Our new results confirm that the age-progressive basement of the Walvis Ridge reflects only the enriched Gough component with no evidence of the Tristan component being present (Hoernle et al., 2015; Nat. Comm.). Superimposed large seamounts (including ridge- and guyot-like structures), especially in the SE portion of the Walvis Ridge, belong to a later-stage of alkalic volcanism with distinct HIMU incompatible element and Sr-Nd-Pb-Hf isotopic composition. The HIMU late-stage volcanism (206Pb/204Pb up to 20.8) is similar in composition to St. Helena and a late-stage (Eocene) sample from the Rio Grande Rise (Rohde et al., 2013; Tectonophysics 604). The new geochemical, bathymetric and existing age data indicate a magmatic reactivation c. 20-40 Ma after the formation of the Walvis Ridge basement, which may be related to passage of the Walvis Ridge over a batch of upwelling St. Helena type plume material. Our new results indicate a more complex formation of the Walvis Ridge than previously thought, which included two major

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Modeling the Effects of Constant and Variable Temperatures on the Vital Rates of an Age-, Stage-, and Sex-Structured Population by Means of the SANDY Approach.

    PubMed

    Nachman, G; Gotoh, T

    2015-06-01

    We present a general and flexible mathematical model (called SANDY) that can be used to describe many biological phenomena, including the phenology of arthropods. In this paper, we demonstrate how the model can be fitted to vital rates (i.e., rates associated with development, survival, hatching, and oviposition) of the two-spotted spider mite (Tetranychus urticae (Koch)) exposed to different constant temperatures ranging from 15°C to 37.5°C. SANDY was incorporated into an age-, stage- and sex-structured dynamic model, which was fitted to cohort life-tables of T. urticae conducted at five constant temperatures (15, 20, 25, 30, and 35°C). Age- and temperature-dependent vital rates for the three main stages (eggs, immatures, and adults) constituting the life-cycle of mites were adequately described by the SANDY model. The modeling approach allows for simulating the growth of a population in a variable environment. We compared the predicted net reproductive rate (R0) and intrinsic rate of natural increase (rm) at fluctuating temperatures with empirical values obtained from life-table experiments conducted at temperatures that changed with a daily amplitude (±0, ±3, ±6, ±9, and ±12°C) around an average of 22°C. Results show that R0 decreases with increasing amplitude, while rm is more robust to variable temperatures. An advantage of SANDY is that the same simple mathematical expression can be applied to describe all the vital rates. Besides, the approach is not confined to modeling the influence of a single factor on population growth but allows for incorporating the combined effect of several limiting factors, provided that the combined effect of the factors is multiplicative. PMID:26313989

  11. The Effects of Comorbidity and Age on RTOG Study Enrollment in Stage III Non-Small Cell Lung Cancer Patients Who Are Eligible for RTOG Studies

    SciTech Connect

    Firat, Selim; Byhardt, Roger W.; Gore, Elizabeth

    2010-12-01

    Purpose: To determine the influence of measured comorbidity in Radiation Therapy Oncology Group (RTOG) combined modality therapy (CMT) study enrollment in Stage III non-small cell lung cancer (NSCLC). Methods and Materials: One hundred and seventy-one patients with a Karnofsky Performance Score {>=}70 and clinical Stage III NSCLC were analyzed retrospectively for comorbidity, RTOG study eligibility, and enrollment at initial consultation. Effect of comorbidity scores (Cumulative Illness Rating Scale) were tested on patient selection for CMT, RTOG enrollment, and overall survival. Results: Comorbidity (Grade 4; p < 0.005) and use of radiation only (p {<=} 0.001) were associated with inferior survival independent of other factors. Patient selection for CMT was affected by age ({>=}70, p < 0.001), comorbidity (severity index [SI]> 2, p = 0.001), and weight loss (>5%, p = 0.001). Thirty-three patients (19%) were enrolled in a CMT RTOG study (Group 1). Forty-nine patients (29%) were eligible but not enrolled (Group 2), and 57 (33%) were ineligible (Group 3). The most common ineligibility reasons were weight loss (67%) and comorbidity in the exclusion criteria of the RTOG studies (63%). Group 1 patients were the youngest (p = 0.02), with the lowest comorbidity scores (p < 0.001) and SI (p < 0.001) compared with Groups 2 and 3. Group 3 patients were the oldest with the most unfavorable comorbidity profile. Comorbidity scores (SI >2; p = 0.006) and age ({>=}70; p = 0.05) were independent factors influencing RTOG study enrollment in patients meeting study eligibility requirements (Groups 1 and 2). Conclusions: Comorbidity scales could be useful in stratification of patients in advanced lung cancer trials and interpretation of results particularly regarding the elderly population.

  12. Is Pubertal Timing Associated with Psychopathology in Young Adulthood?

    ERIC Educational Resources Information Center

    Graber, Julia A.; Seeley, John R.; Brooks-Gunn, Jeanne; Lewinsohn, Peter M.

    2004-01-01

    Objective: This investigation tested whether the timing of puberty continued to be associated with experiences of psychopathology (symptoms and disorders) from mid-adolescence into young adulthood. Method: At age 24, 931 participants from a large community sample, who had been interviewed twice during adolescence, completed a telephone interview…

  13. A Validation Study of Early Adolescents' Pubertal Self-Assessments

    ERIC Educational Resources Information Center

    Schmitz, Katharine E.; Hovell, Melbourne F.; Nichols, Jeanne F.; Irvin, Veronica L.; Keating, Kristen; Simon, Gayle M.; Gehrman, Christine; Jones, Kenneth Lee

    2004-01-01

    This study aimed to determine whether self-assessed puberty is sufficiently reliable and valid to substitute for physician examination when feasibility of physician examination is low (e.g., behavioral research). Adolescents (convenience sample N = 178 endocrinology patients and N = 125 from educational trial; mean age 12.7 and 11.3 years,…

  14. Pubertal Development and Prepubertal Height and Weight Jointly Predict Young Adult Height and Body Mass Index in a Prospective Study in South Africa12

    PubMed Central

    Martorell, Reynaldo; Richter, Linda M

    2016-01-01

    Background: Height and adiposity track over childhood, but few studies, to our knowledge, have longitudinally examined the mediating relation of the timing and progression of puberty. Objective: We assessed interrelations between prepubertal height and body mass index, the progression through puberty, and young adult height and adiposity. Methods: We analyzed data from the Birth to Twenty Plus study (females, n = 823; males, n = 765). Serial measures of anthropometry and pubertal development were obtained between ages 9 and 16 y. We used latent class growth analysis to categorize pubertal development with respect to pubic hair (females and males), breasts (females), and genitalia (males) development. Adult height and weight were obtained at ages 18 to 20 y. Results: Among females, higher latent class (earlier initiation and faster progression through puberty) was associated with an increased risk of obesity [pubic hair class 3 compared with class 1: RR, 3.41 (95% CI: 1.57, 7.44)] and inconsistent associations with height. Among males, higher latent class was associated with increased adult height [pubic hair development class 3 compared with class 1: 2.43 cm (95% CI: 0.88, 4.00)] and increased risk of overweight/obesity [pubic hair development class 3 compared with class 1: OR, 3.44 (95% CI: 1.44, 8.20)]. In females, the association with adult height became inverse after adjusting for prepubertal height [pubic hair development class 3 compared with class 1: females, −1.31 cm (95% CI: −2.32, −0.31)]; in males, the association with height was attenuated with this adjustment [−0.56 cm (95% CI: −1.63, 0.52)]. Associations with adiposity were attenuated after adjusting for prepubertal adiposity. Conclusions: Progression through puberty modifies the relation between prepubertal and adult anthropometry. Screening for early or rapid progression of puberty might identify children at an increased risk of becoming overweight or obese adults. PMID:27335138

  15. Elevated pentraxin 3 level at the early stage of exercise training is associated with reduction of arterial stiffness in middle-aged and older adults.

    PubMed

    Zempo-Miyaki, A; Fujie, S; Sato, K; Hasegawa, N; Sanada, K; Maeda, S; Hamaoka, T; Iemitsu, M

    2016-09-01

    Regular exercise improves aging-induced deterioration of arterial stiffness, and is associated with elevated production of pentraxin 3 (PTX3) and anti-inflammatory as well as anti-atherosclerotic effects. However, the time-dependent effect of exercise training on arterial stiffness and PTX3 production remains unclear. The purpose of this study was to investigate the time course of the association between the effects of training on the circulating PTX3 level and arterial stiffness in middle-aged and older adults. Thirty-two healthy Japanese subjects (66.2±1.3 year) were randomly divided into two groups: training (exercise intervention) and sedentary controls. Subjects in the training group completed 8 weeks of aerobic exercise training (60-70% peak oxygen uptake (VO2peak) for 45 min, 3 days per week); during the training period, we evaluated plasma PTX3 concentration and carotid-femoral pulse wave velocity (cfPWV) every 2 wk. cfPWV gradually declined over the 8-week training period, and was significantly reduced after 6 and 8 week of exercise intervention (P<0.05). Plasma PTX3 level was significantly increased after 4 weeks of the intervention (P<0.05). In addition, the exercise training-induced reduction in cfPWV was negatively correlated with the percent change in plasma PTX3 level after 6 week (r=-0.54, P<0.05) and 8 weeks (r=-0.51, P<0.05) of the intervention, but not correlated at 4 weeks. Plasma PTX3 level was elevated at the early stage of the exercise training intervention, and was subsequently associated with training-induced alteration of arterial stiffness in middle-aged and older adults.

  16. Reproductive ageing in women.

    PubMed

    Djahanbakhch, O; Ezzati, M; Zosmer, A

    2007-01-01

    The traditional view in respect to female reproduction is that the number of oocytes at birth is fixed and continuously declines towards the point when no more oocytes are available after menopause. In this review we briefly discuss the embryonic development of female germ cells and ovarian follicles. The ontogeny of the hypothalamic-pituitary-gonadal axis is then discussed, with a focus on pubertal transition and normal ovulatory menstrual cycles during female adult life. Biochemical markers of menopausal transition are briefly examined. We also examine the effects of age on female fertility, the contribution of chromosomal abnormalities of the oocyte to the observed decline in female fertility with age and the possible biological basis for the occurrence of such abnormalities. Finally, we consider the effects of maternal age on obstetric complications and perinatal outcome. New data that have the potential to revolutionize our understanding of mammalian oogenesis and follicular formation, and of the female reproductive ageing process, are also briefly considered.

  17. Stage IV and age over 45 years are the only prognostic factors of the International Prognostic Score for the outcome of advanced Hodgkin lymphoma in the Spanish Hodgkin Lymphoma Study Group series.

    PubMed

    Guisado-Vasco, Pablo; Arranz-Saez, Reyes; Canales, Miguel; Cánovas, Araceli; Garcia-Laraña, José; García-Sanz, Ramón; Lopez, Andrés; López, José Luis; Llanos, Marta; Moraleda, José Maria; Rodriguez, José; Rayón, Consuelo; Sabin, Pilar; Salar, Antonio; Marín-Niebla, Ana; Morente, Manuel; Sánchez-Godoy, Pedro; Tomás, José Francisco; Muriel, Alfonso; Abraira, Victor; Piris, Miguel A; Garcia, Juán F; Montalban, Carlos

    2012-05-01

    The International Prognostic Score (IPS) is the most widely used system to date for identifying risk groups for the outcome of patients with advanced Hodgkin lymphoma, although important limitations have been recognized. We analyzed the value of the IPS in a series of 311 patients with advanced classical Hodgkin lymphoma (cHL) (Ann Arbor stage III, IV or stage II with B symptoms and/or bulky masses) treated with first-line chemotherapy including adriamycin (adriamycin, bleomycin, vinblastine, dacarbazine [ABVD] or equivalent variants). In univariate and multivariate analyses, stage IV disease and age ≥ 45 years were the only factors with independent predictive significance for overall survival (OS) (p = 0.002 and p < 0.001, respectively). Stage IV was still significant for freedom from progression (FFP) (p = 0.001) and age ≥ 45 years was borderline significant (p = 0.058). IPS separates prognostic groups, as in the original publication, but this is mainly due to the high statistical significance of stage IV and age ≥ 45 years. Moreover, the combination of these two factors enables a simpler system to be constructed that separates groups with different FFP and OS. In conclusion, in our series, stage IV and age ≥ 45 years are the key prognostic factors for the outcome of advanced cHL.

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

    PubMed

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

    2016-07-01

    Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P < 0.05), which was largely due to a 6.4-7.8 % (P < 0.05) greater cortical mass in the posterior-lateral, medial and posterior-medial 66 % tibial regions. Cortical area was not significantly different across PA-fitness categories in girls, but active-fit girls had 6.1 % (P < 0.05) greater SSIpolar compared to inactive-fit girls, which was likely due to their 6.7 % (P < 0.05) greater total bone area. There was also a small region-specific cortical mass benefit in the posterior-medial 66 % tibia cortex in active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.

  19. [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.

  20. Validity of the ages and stages questionnaires in Korean compared to Bayley Scales of infant development-II for screening preterm infants at corrected age of 18-24 months for neurodevelopmental delay.

    PubMed

    Kwun, Yoojin; Park, Hye Won; Kim, Min-Ju; Lee, Byong Sop; Kim, Ellen Ai-Rhan

    2015-04-01

    This study aimed to evaluate the validity of the ages and stages questionnaire in Korean (ASQ 1st edition, Korean Questionnaires, Seoul Community Rehabilitation Center, 2000) for premature infants. The study population consisted of 90 premature infants born between January 1, 2005, and December 31, 2011, who were tested using the ASQ (Korean) and Bayley Scales of Infant Development (BSID) (II) at a corrected age of 18-24 months. The validity of the ASQ (Korean) using cut-off values set at < -2 SD was examined by comparing it to the BSID (II) components, namely, the mental developmental index (MDI) or psychomotor developmental index (PDI), which were both set at < 85. The calculation of the sensitivities, specificities, positive predictive values, and negative predictive values of the ASQ (Korean) components revealed that they detected infants with neurodevelopmental delay with low sensitivity and positive predictive values, however, the communication domain showed moderate correlations with MDI. The failure in more than one domain of the ASQ (Korean) was significantly correlated with the failure in MDI. The ASQ (Korean) showed low validity for screening neurodevelopmentally delayed premature infants. PMID:25829813

  1. Validity of the ages and stages questionnaires in Korean compared to Bayley Scales of infant development-II for screening preterm infants at corrected age of 18-24 months for neurodevelopmental delay.

    PubMed

    Kwun, Yoojin; Park, Hye Won; Kim, Min-Ju; Lee, Byong Sop; Kim, Ellen Ai-Rhan

    2015-04-01

    This study aimed to evaluate the validity of the ages and stages questionnaire in Korean (ASQ 1st edition, Korean Questionnaires, Seoul Community Rehabilitation Center, 2000) for premature infants. The study population consisted of 90 premature infants born between January 1, 2005, and December 31, 2011, who were tested using the ASQ (Korean) and Bayley Scales of Infant Development (BSID) (II) at a corrected age of 18-24 months. The validity of the ASQ (Korean) using cut-off values set at < -2 SD was examined by comparing it to the BSID (II) components, namely, the mental developmental index (MDI) or psychomotor developmental index (PDI), which were both set at < 85. The calculation of the sensitivities, specificities, positive predictive values, and negative predictive values of the ASQ (Korean) components revealed that they detected infants with neurodevelopmental delay with low sensitivity and positive predictive values, however, the communication domain showed moderate correlations with MDI. The failure in more than one domain of the ASQ (Korean) was significantly correlated with the failure in MDI. The ASQ (Korean) showed low validity for screening neurodevelopmentally delayed premature infants.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. Pubertal activation of estrogen receptor α in the medial amygdala is essential for the full expression of male social behavior in mice.

    PubMed

    Sano, Kazuhiro; Nakata, Mariko; Musatov, Sergei; Morishita, Masahiro; Sakamoto, Toshiro; Tsukahara, Shinji; Ogawa, Sonoko

    2016-07-01

    Testosterone plays a central role in the facilitation of male-type social behaviors, such as sexual and aggressive behaviors, and the development of their neural bases in male mice. The action of testosterone via estrogen receptor (ER) α, after being aromatized to estradiol, has been suggested to be crucial for the full expression of these behaviors. We previously reported that silencing of ERα in adult male mice with the use of a virally mediated RNAi method in the medial preoptic area (MPOA) greatly reduced sexual behaviors without affecting aggressive behaviors whereas that in the medial amygdala (MeA) had no effect on either behavior. It is well accepted that testosterone stimulation during the pubertal period is necessary for the full expression of male-type social behaviors. However, it is still not known whether, and in which brain region, ERα is involved in this developmental effect of testosterone. In this study, we knocked down ERα in the MeA or MPOA in gonadally intact male mice at the age of 21 d and examined its effects on the sexual and aggressive behaviors later in adulthood. We found that the prepubertal knockdown of ERα in the MeA reduced both sexual and aggressive behaviors whereas that in the MPOA reduced only sexual, but not aggressive, behavior. Furthermore, the number of MeA neurons was reduced by prepubertal knockdown of ERα. These results indicate that ERα activation in the MeA during the pubertal period is crucial for male mice to fully express their male-type social behaviors in adulthood. PMID:27325769

  7. Pubertal administration of DEHP delays puberty, suppresses testosterone production, and inhibits reproductive tract development in male Sprague-Dawley and Long-Evans rats.

    PubMed

    Noriega, Nigel C; Howdeshell, Kembra L; Furr, Jonathan; Lambright, Christy R; Wilson, Vickie S; Gray, L Earl

    2009-09-01

    Although is clear that exposure to high dosage levels of some phthalates delays the onset of puberty in the male rat, it has been hypothesized that low levels of di(2-ethylhexyl) phthalate (DEHP) accelerate puberty by enhancing testicular androgen synthesis. The current study was designed to determine if the dose response to DEHP was nonmonotonic, as hypothesized. Pubertal administration of DEHP delayed the onset of puberty and reduced androgen-dependent tissue weights in both Long-Evans (LE) and Sprague-Dawley (SD) male rats 300 and 900 mg DEHP/kg/day. These effects were generally of greater magnitude in LE than SD rats. By contrast, alterations in testis histopathology (300 and 900 mg/kg/day) were more severe in SD than in LE rats. Taken together, these results suggest that DEHP may be acting on the pubertal male rat testis via two modes of action; one via the Leydig cells and the other via the Sertoli cells. Treatment with DEHP generally reduced serum testosterone and increased serum luteinizing hormone (LH) levels, demonstrating that the reduction in testosterone was due to the effect of DEHP on the testis and not via an inhibition of LH from hypothalamic-pituitary axis. Testosterone production ex vivo (with and without human chorionic gonadotropin stimulation) was consistently reduced in males at the time of puberty and shortly thereafter. DEHP treatment did not accelerate the age at puberty or enhance testosterone levels at 10 or 100 mg/kg/day in either LE or SD rats, as some have hypothesized. Taken together, these results do not provide any evidence of a nonmonotonic dose response to DEHP during puberty.

  8. Age-related changes in protein metabolism of beech (Fagus sylvatica L.) seeds during alleviation of dormancy and in the early stage of germination.

    PubMed

    Ratajczak, Ewelina; Kalemba, Ewa M; Pukacka, Stanislawa

    2015-09-01

    The long-term storage of seeds generally reduces their viability and vigour. The aim of this work was to evaluate the effect of long-term storage on beech (Fagus sylvatica L.) seeds at optimal conditions, over 9 years, on the total and soluble protein levels and activity of proteolytic enzymes, including endopeptidases, carboxypeptidases and aminopeptidases, as well as free amino acid levels and protein synthesis, in dry seeds, after imbibition and during cold stratification leading to dormancy release and germination. The same analyses were conducted in parallel on seeds gathered from the same tree in the running growing season and stored under the same conditions for only 3 months. The results showed that germination capacity decreased from 100% in freshly harvested seeds to 75% in seeds stored for 9 years. The levels of total and soluble proteins were highest in freshly harvested seeds and decreased significantly during storage, these proportions were retained during cold stratification and germination of seeds. Significant differences between freshly harvested and stored seeds were observed in the activities of proteolytic enzymes, including endopeptidases, aminopeptidases and carboxypeptidases, and in the levels of free amino acids. The neosynthesis of proteins during dormancy release and in the early stage of seed germination was significantly weaker in stored seeds. These results confirm the importance of protein metabolism for seed viability and the consequences of its reduction during seed ageing.

  9. Tandem high-dose chemotherapy and autologous stem cell rescue in patients over 1 year of age with stage 4 neuroblastoma.

    PubMed

    Sung, K W; Lee, S H; Yoo, K H; Jung, H L; Cho, E J; Koo, H H; Lee, S K; Kim, J; Lim, D H; Suh, Y L; Kim, D W

    2007-07-01

    From June 1997 to August 2005, 52 consecutive newly diagnosed stage 4 neuroblastoma patients over 1 year of age were assigned to receive tandem high-dose chemotherapy and autologous stem cell rescue (HDCT/ASCR) as consolidation therapy. Fifty of the 52 patients underwent a first HDCT/ASCR and 44 patients underwent a second HDCT/ASCR. Eight patients (15.4%) died from treatment-related toxicity (seven during the second HDCT/ASCR). Total body irradiation (TBI) in the first HDCT/ASCR and a shorter interval (< 12 weeks) between the first and second HDCT/ASCR were associated with a higher rate of treatment-related death in the second HDCT/ASCR (P = 0.032 and 0.095, respectively). The tumor relapsed or progressed in 11 patients, and 33 patients remained event free with a median follow-up of 53 months (range 19-117) from diagnosis. The 5-year event-free survival (EFS) (+/- 95% confidence interval) for all 52 patients was 62.1+/-13.7%. The application of TBI and local radiotherapy, and a longer interval between the first and second HDCT/ASCR were independently associated with a better EFS (P = 0.026, 0.007 and 0.020, respectively). However, further studies will be needed to decrease the toxic death rate in the second HDCT/ASCR while reducing the relapse rate.

  10. Age-related changes in protein metabolism of beech (Fagus sylvatica L.) seeds during alleviation of dormancy and in the early stage of germination.

    PubMed

    Ratajczak, Ewelina; Kalemba, Ewa M; Pukacka, Stanislawa

    2015-09-01

    The long-term storage of seeds generally reduces their viability and vigour. The aim of this work was to evaluate the effect of long-term storage on beech (Fagus sylvatica L.) seeds at optimal conditions, over 9 years, on the total and soluble protein levels and activity of proteolytic enzymes, including endopeptidases, carboxypeptidases and aminopeptidases, as well as free amino acid levels and protein synthesis, in dry seeds, after imbibition and during cold stratification leading to dormancy release and germination. The same analyses were conducted in parallel on seeds gathered from the same tree in the running growing season and stored under the same conditions for only 3 months. The results showed that germination capacity decreased from 100% in freshly harvested seeds to 75% in seeds stored for 9 years. The levels of total and soluble proteins were highest in freshly harvested seeds and decreased significantly during storage, these proportions were retained during cold stratification and germination of seeds. Significant differences between freshly harvested and stored seeds were observed in the activities of proteolytic enzymes, including endopeptidases, aminopeptidases and carboxypeptidases, and in the levels of free amino acids. The neosynthesis of proteins during dormancy release and in the early stage of seed germination was significantly weaker in stored seeds. These results confirm the importance of protein metabolism for seed viability and the consequences of its reduction during seed ageing. PMID:26071872

  11. Trends in 'cure' fraction from colorectal cancer by age and tumour stage between 1975 and 2000, using population-based data, Osaka, Japan.

    PubMed

    Ito, Yuri; Nakayama, Tomio; Miyashiro, Isao; Sugimoto, Tomoyuki; Ioka, Akiko; Tsukuma, Hideaki; Abdel-Rahman, Manar E; Rachet, Bernard

    2012-10-01

    Since the 1960s, Japan has experienced a striking increase in the incidence of colorectal cancer, now the second most common cancer in the country. Meanwhile, the management of colorectal cancer has changed dramatically with the implementation of, for example, screening, endoscopy and adjuvant chemotherapy. It is therefore of interest to monitor the long-term trends in population 'cure' in Japan. We analysed 33 885 colorectal cancer cases diagnosed between 1975 and 2000 in Osaka. We applied the multivariable mixture cure model to estimate cure fraction and median survival time (MST) for 'uncured' patients, by sex, age, stage, period at diagnosis and subsite. For colon cancer, the cure fraction increased by about 25%, while MST for the uncured was prolonged from 8 to 12 months. The cure fraction was 5% higher in men than in women, while MST was similar in both. The cure fraction also increased for localized and regional tumours. For rectal cancer, the cure fraction increased by about 25-30%, but remained lower than for colon cancer. From the late 1970s, the cure fraction for colorectal cancer increased dramatically due to better management of detection and care for colorectal cancer. This improvement was obtained at the cost of shorter MST for uncured patients.

  12. 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.

  13. Optimal therapy of pubertal disorders in precocious/early puberty.

    PubMed

    Tatò, L; Savage, M O; Antoniazzi, F; Buzi, F; Di Maio, S; Oostdijk, W; Pasquino, A M; Raiola, G; Saenger, P; Tonini, G; Voorhoeve, P G

    2001-07-01

    GnRHa have been used in the treatment of central precocious puberty (CPP) for a decade and some final results of this therapy are now available. Treatment preserves height potential in younger patients and a complete recovery of the hypothalamic-pituitary-gonadal axis occurs at the end of treatment. However, some aspects of the management of CPP are still debated. Probably the age limits between normal and precocious puberty have to be lowered, and new diagnostic tools will modify and simplify diagnostic criteria. The possibility of progression of premature thelarche into precocious puberty, the pathogenesis of organic and idiopathic precocious puberty, the criteria for decision to treat and to stop treatment and the utility of an association with GH treatment will be better understood in the future. Follow-up of patients after stopping therapy includes frequency and characteristics of menses, the possible higher incidence of polycystic ovary-like syndrome and the correct achievement of a normal peak bone mass and body composition. In this review we discuss some of these points, with particular attention to precocious puberty in girls.

  14. Preteen insulin levels interact with caloric intake to predict increases in obesity at ages 18 to 19 years: a 10-year prospective study of black and white girls.

    PubMed

    Morrison, John A; Glueck, Charles J; Wang, Ping

    2010-05-01

    We evaluated the associations of teenage insulin and adolescent diet with 10-year weight gain in an analysis sample of black and white girls matched for pubertal stage, body mass index (BMI) (or fat mass), and insulin at ages 9 to 10 years. We hypothesized that preteen insulin and insulin resistance would interact with dietary factors to positively predict increases in BMI. Furthermore, we hypothesized that increased insulin and insulin resistance, interacting with higher caloric intake during adolescence, would lead to greater increments in BMI in black girls than in white girls. Prospective 10-year follow-up was performed on 215 pairs of black and white schoolgirls matched at baseline by BMI (or fat mass), insulin, and pubertal stage, with repeated measures of body habitus, insulin, and dietary intake. When matched for BMI, black girls had higher fat-free mass and white girls had higher fat mass at ages 9 to 10 years. Black-white differences in caloric intake were not significant at ages 9 to 10 years, but black girls consumed more calories at age 19 years. Black girls consumed a greater percentage of calories from fat throughout. At age 19 years, black girls had higher BMI, fat mass index, and insulin. When matched at ages 9 to 10 years for fat mass, black girls were heavier, had higher BMI, and had greater fat-free mass. By ages 18 to 19 years, black girls continued to have higher BMI, but had accrued higher fat mass and a higher percentage of body fat. By stepwise multiple regression, 10-year increases in BMI were predicted by ages 9 to 10 years BMI, 10-year change in insulin, and a 3-way interaction between ages 9 to 10 years insulin, adolescent caloric intake, and race (higher in black girls) (all Ps < .0001). Insulin at ages 9 to 10 years interacts with caloric intake to increase BMI by age 19 years. There appear to be intrinsic black-white metabolic differences that lead to greater gains in fat during adolescence in black girls. Evaluating BMI and insulin

  15. Preteen insulin levels interact with caloric intake to predict increases in obesity at ages 18 to 19 years: a 10-year prospective study of black and white girls.

    PubMed

    Morrison, John A; Glueck, Charles J; Wang, Ping

    2010-05-01

    We evaluated the associations of teenage insulin and adolescent diet with 10-year weight gain in an analysis sample of black and white girls matched for pubertal stage, body mass index (BMI) (or fat mass), and insulin at ages 9 to 10 years. We hypothesized that preteen insulin and insulin resistance would interact with dietary factors to positively predict increases in BMI. Furthermore, we hypothesized that increased insulin and insulin resistance, interacting with higher caloric intake during adolescence, would lead to greater increments in BMI in black girls than in white girls. Prospective 10-year follow-up was performed on 215 pairs of black and white schoolgirls matched at baseline by BMI (or fat mass), insulin, and pubertal stage, with repeated measures of body habitus, insulin, and dietary intake. When matched for BMI, black girls had higher fat-free mass and white girls had higher fat mass at ages 9 to 10 years. Black-white differences in caloric intake were not significant at ages 9 to 10 years, but black girls consumed more calories at age 19 years. Black girls consumed a greater percentage of calories from fat throughout. At age 19 years, black girls had higher BMI, fat mass index, and insulin. When matched at ages 9 to 10 years for fat mass, black girls were heavier, had higher BMI, and had greater fat-free mass. By ages 18 to 19 years, black girls continued to have higher BMI, but had accrued higher fat mass and a higher percentage of body fat. By stepwise multiple regression, 10-year increases in BMI were predicted by ages 9 to 10 years BMI, 10-year change in insulin, and a 3-way interaction between ages 9 to 10 years insulin, adolescent caloric intake, and race (higher in black girls) (all Ps < .0001). Insulin at ages 9 to 10 years interacts with caloric intake to increase BMI by age 19 years. There appear to be intrinsic black-white metabolic differences that lead to greater gains in fat during adolescence in black girls. Evaluating BMI and insulin

  16. Pubertal development in female Wistar rats following exposure to propazine and atrazine biotransformation by-products, diamino-S-chlorotriazine and hydroxyatrazine.

    PubMed

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

    2003-11-01

    We showed previously that the chlorotriazine herbicide, atrazine (ATR), delays the onset of pubertal development in female rats. ATR and its biotransformation by-products are present in soil and groundwater. Since current maximum contaminant levels are set only for ATR, it is important to determine whether these by-products can also alter pubertal development and possibly pose a cumulative exposure hazard. We evaluated the effects of two ATR by-products, diamino-s-chlorotriazine (DACT) and hydroxyatrazine (OH-ATR), and a structurally similar chlorotriazine, propazine (PRO), on female pubertal development. Rats were gavaged from postnatal days (PNDs) 22 through PND 41 with DACT (16.7, 33.8, 67.5, 135 mg/kg), OH-ATR (22.8, 45.7, 91.5, 183 mg/kg), or PRO (13, 26.7, 53, 106.7, 213 mg/kg). The dose range for each chemical was selected as the molar equivalent of ATR (12.5, 25, 50, 100, 200 mg/kg). The females were monitored daily for vaginal opening (VO) and killed on PND 41. DACT, a by-product of ATR that occurs in the environment and is also the primary chlorinated metabolite of ATR in animal tissue, delayed VO by 3.2, 4.8, and 7.6 days compared to the controls (33.1 +/- 0.4 (SE) days of age) following exposure to 33.8, 67.5, and 135 mg/kg, respectively. The no effect level (NOEL) for DACT (16.7 mg/kg) was identical to the equimolar NOEL for ATR (25 mg/kg). Although the body weight (BW) on PND 41 was reduced by the high dose of DACT (8.4% reduction), this reduction did not exceed the criteria for selecting the maximum tolerated dose (e.g., a dose that causes >10% decrease in BW at necropsy). None of the lower doses of DACT caused a significant difference in BW gain. Additionally, 33.8, 67.5, and 135 mg/kg of DACT significantly increased the BW on the day of VO. PRO (107 or 213 mg/kg) delayed VO by 4 days but did not alter the BW on PND 41. While no significant delays in pubertal development were observed in two separate dose-response studies with doses ranging up to

  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. 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.

  19. Differential proteomic profile of spermatogenic and Sertoli cells from peri-pubertal testes of three different bovine breeds

    PubMed Central

    Tripathi, Utkarsh K.; Aslam, Muhammad K. M.; Pandey, Shashank; Nayak, Samiksha; Chhillar, Shivani; Srinivasan, A.; Mohanty, T. K.; Kadam, Prashant H.; Chauhan, M. S.; Yadav, Savita; Kumaresan, Arumugam

    2014-01-01

    Sub-fertility is one of the most common problems observed in crossbred males, but the etiology remains unknown in most of the cases. Although proteomic differences in the spermatozoa and seminal plasma between breeds have been investigated, the possible differences at the sperm precursor cells and supporting/nourishing cells have not been studied. The present study reports the differential proteomic profile of spermatogenic and Sertoli cells in crossbred and purebred bulls. Testis was removed by unilateral castration of 12 peri-pubertal bulls (10 months age), four each from crossbred (Holstein Friesian × Tharparkar), exotic purebred [Holstein Friesian (HF)] and indigenous purebred [Tharparkar (TP)] bulls. Spermatogenic and Sertoli cells were isolated and subjected to proteomic analysis. Protein extracts from the Sertoli and spermatogenic cells of each breed were analyzed with 2-dimensional difference gel electrophoresis (2D-DIGE) and analyzed with Decyder™ software. Compared to HF, 26 protein spots were over expressed and 14 protein spots were under expressed in spermatogenic cells of crossbred bulls. Similarly, 7 protein spots were over expressed and 15 protein spots were under expressed in the spermatogenic cells of TP bulls compared to that of crossbred bulls. Out of 12 selected protein spots identified through mass spectrometry, Phosphatidyl ethanolamine binding protein was found to be over expressed in the spermatogenic cells of crossbred bulls compared to TP bulls. The protein, gamma actin was found to be over expressed in the Sertoli cells of HF bulls, whereas Speedy Protein-A was found to be over expressed in Sertoli cells of crossbred bulls. It may be concluded that certain proteomic level differences exist in sperm precursor cells and nourishing cells between breeds, which might be associated with differences in the fertility among these breeds. PMID:25364731

  20. 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

  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. Assessment of Stage of Change, Decisional Balance, Self-Efficacy, and Use of Processes of Change of Low-Income Parents for Increasing Servings of Fruits and Vegetables to Preschool-Aged Children

    ERIC Educational Resources Information Center

    Hildebrand, Deana A.; Betts, Nancy M.

    2009-01-01

    Objective: Use the Transtheoretical Model of Behavior Change (TTM) to determine the proportionate stage of change of low-income parents and primary caregivers (PPC) for increasing accessibility, measured as servings served, of fruits and vegetables (FV) to their preschool-aged children and evaluate response differences for theoretical constructs.…

  3. Long-term (60-month) results for the implantable miniature telescope: efficacy and safety outcomes stratified by age in patients with end-stage age-related macular degeneration

    PubMed Central

    Boyer, David; Freund, K Bailey; Regillo, Carl; Levy, Marc H; Garg, Sumit

    2015-01-01

    Background The purpose of this study was to evaluate the long-term results of an implantable miniature telescope (IMT) in patients with bilateral, end-stage, age-related macular degeneration (AMD). Methods A prospective, open-label, multicenter clinical trial with fellow eye controls enrolled 217 patients (mean age 76 years) with AMD and moderate-to-profound bilateral central visual acuity loss (20/80–20/800) resulting from untreatable geographic atrophy, disciform scars, or both. A subgroup analysis was performed with stratification for age (patient age 65 to <75 years [group 1; n=70] and patient age ≥75 years [group 2; n=127]), with a comparative evaluation of change in best-corrected distance visual acuity (BCDVA), quality of life, ocular complications from surgery, adverse events, and endothelial cell density (ECD). Follow-up in an extension study was 60 months. Results Data were available for 22, 38, and 31 patients in group 1 and 42, 46, and 32 patients in group 2 at 36, 48, and 60 months, respectively. Mean BCDVA improvement from baseline to 60 months was 2.41±2.69 lines in all patients (n=76), with 2.64±2.55 lines in group 1 and 2.09±2.88 lines in group 2. Quality of life scores were significantly higher in group 1. The most common significant surgery-related ocular complications in group 1 were iritis >30 days after surgery (7/70; 10%) and persistent corneal edema (3/70; 4.3%); and in group 2 were a decrease in BCDVA in the implanted eye or IMT removal (10/127 each; 7.9%), corneal edema >30 days after surgery (9/127; 7.1%), and persistent corneal edema (6/127; 4.7%). Significant adverse events included four corneal transplants, comprising two (2.9%) in group 1 and two (1.6%) in group 2. At 60 months, one patient in group 1 (3.2%) and three patients in group 2 (9.4%) had lost ≥2 lines of vision. The IMT was removed in one (1.4%) and ten (7.9%) patients in group 1 and group 2, respectively. Mean ECD loss was 20% at 3 months. Chronic loss was 3% per

  4. 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,...

  5. 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…

  6. 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...

  7. 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...

  8. 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…

  9. 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,…

  10. 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…

  11. 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…

  12. 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...

  13. 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...

  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. 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

  17. 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.

  18. 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

  19. 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

  20. 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

  1. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic.

    PubMed

    Barreto, Rodrigo R; de Farias, Wialla K T; Andrade, Humber; Santana, Francisco M; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  2. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic

    PubMed Central

    Barreto, Rodrigo R.; de Farias, Wialla K. T.; Andrade, Humber; Santana, Francisco M.; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  3. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic.

    PubMed

    Barreto, Rodrigo R; de Farias, Wialla K T; Andrade, Humber; Santana, Francisco M; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. Immunohistochemical evaluation of apoptosis and proliferation in the mucous membrane of selected uterine regions in pre-pubertal bitches exposed to low doses of zearalenone.

    PubMed

    Stopa, E; Babińska, I; Zielonka, Ł; Gajęcki, M; Gajęcka, M

    2016-01-01

    Mycotoxins are toxic secondary metabolites produced by fungi. Those biologically active compounds occur naturally and they include zearalenone (ZEN), a mycotoxin that contaminates plant material, including the ingredients used in the production of commercial dog food. The influence of monotonic, low-dose and long-term exposure to ZEN on pre-pubertal bitches has not been fully explored to date. This paper describes a 42-day experiment performed on clinically healthy female dogs aged approximately 70 days, with estimated body weight of 8 kg. The animals were randomly divided into two experimental groups (EI and EII) and a control group (C) of 10 animals each. Group EI received 50 μg ZEN/kg (of body weight) per os, group EII received 75 μg ZEN/kg BW per os, and the control group was administered placebo. The bitches were ovariohysterectomized at the end of the experiment (at around 112 days of age), and selected sections of the uterine wall were subjected to immunohistochemical analyses (TUNEL and PCNA). A shift towards higher apoptotic (AI) and proliferative index (PI) was observed, in particular in group EI. Higher AI and PI values were noted in the epithelium of all uterine regions analysed and in the uterine glands in the uterine horn proximal to the body of the uterus. PMID:27096802

  10. Suppression of urinary and plasma follicle-stimulating hormone by exogenous estrogens in prepubertal and pubertal children.

    PubMed

    Kelch, R P; Kaplan, S L; Ghumbach, M M

    1973-05-01

    Clomiphene citrate, an "anti-estrogen" with mild estrogenic properties, inhibits rather than stimulates gonadotropin excretion in prepubertal and early pubertal children. These and other data suggest that the sensitivity of the hypothalamic-pituitary "gonadostat" decreases at the onset of puberty. To test this hypothesis further, the daily excretion of urinary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was determined in 19 children (5 "short normals" and 14 with isolated human growth hormone (HGH) deficiency) who were given ethinyl estradiol (EE) 1.4-14.7 mug/m(2) per day (2-10 mug/day) for 4 to 7 days. In addition, plasma and urinary gonadotropins and plasma estrogens were serially determined in two prepubertal females(with isolated HGH deficiency) given two injections (24 h apart) of estradiol benzoate, 10 mug/kg. FSH and LH concentrations in plasma and kaolin-acetone urinary concentrates and plasma 17beta-estradiol (E(2)) and estrone (E(1)) were measured by radioimmunoassays. 2-3 mug/m(2) per day of EE significantly suppressed urinary FSH (and LH when detected in the control period) in two out of six prepubertal children, while all doses >5 mug/m(2) per day suppressed urinary gonadotropins to undetectable levels in eight prepubertal subjects. In early to midpubertal subjects. 2-10 mug/m(2) per day of EE produced a slight suppression of urinary FSH, but failed to suppress to undetectable levels. Two subjects in late puberty (stage 4) did not suppress their urinary FSH while on 7 and 8.3 mug/m(2) per day. In both subjects treated with estradiol benzoate, plasma FSH promptly decreased after the first injection. Urinary FSH was suppressed to <0.1 IU/day on day 2 and urinary and plasma gonadotropins remained suppressed for the duration of the study (3 days). Plasma E(2) and E(1) rose from prepubertal values to peak concentrations of 150 to 250 pg/ml (E(2)), and 50 and 100 pg/ml (E(1)) at approximately 36 h. We conclude that the hypothalamic

  11. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study

    PubMed Central

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD. PMID:27672476

  12. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study

    PubMed Central

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD.

  13. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study.

    PubMed

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie; Krantic, Slavica

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD. PMID:27672476

  14. Estimating Stage-Specific Vital Rate Responses to Stress within Mixed Age Populations of the Opossum Shrimp Americamysis Bahia Using Digital Imaging (NAC SETAC 2011)

    EPA Science Inventory

    Most observations of stressor effects on marine crustaceans are made on individuals or even-aged cohorts. Results of these studies are difficult to translate into ecological predictions, either because life cycle models are incomplete, or because stressor effects on mixed age po...

  15. Estimating Stage Specific Vital Rate Responses to Stress Within Mixed Age Populations of the Opossum Shrimp Americamysis bahia Using Digital Imaging

    EPA Science Inventory

    Most observations of stressor effects on marine crustaceans are made on individuals or even-aged cohorts. Results of these studies are difficult to translate into ecological predictions, either because life cycle models are incomplete, or because stressor effects on mixed age po...

  16. Stage design

    DOEpatents

    Shacter, J.

    1975-12-01

    A method is described of cycling gases through a plurality of diffusion stages comprising the steps of admitting the diffused gases from a first diffusion stage into an axial compressor, simultaneously admitting the undiffused gases from a second diffusion stage into an intermediate pressure zone of said compressor corresponding in pressure to the pressure of said undiffused gases, and then admitting the resulting compressed mixture of diffused and undiffused gases into a third diffusion stage.

  17. Effect of Aging in the Perception of Health-Related Quality of Life in End-Stage Renal Disease Patients under Online-Hemodiafiltration.

    PubMed

    Moura, Alexandra; Madureira, José; Alija, Pablo; Fernandes, João Carlos; Oliveira, José Gerardo; Lopez, Martin; Filgueiras, Madalena; Amado, Leonilde; Sameiro-Faria, Maria; Miranda, Vasco; Santos-Silva, Alice; Costa, Elísio

    2015-02-01

    This work aimed to evaluate how aging could influence patients' perception of health quality of life (HRQOL), as well as, the effect of aging on dialysis adequacy and in hematological, iron status, inflammatory and nutritional markers. In this transversal study were enrolled 305 ESRD patients under online-hemodiafiltration (OL-HDF) (59.67% males; 64.9 ± 14.3 years old). Data about comorbidities, hematological data, iron status, dialysis adequacy, nutritional and inflammatory markers were collected from patient's records. Moreover, HRQOL score, by using the Kidney Disease Quality of Life-Short Form (KDQOL-SF), was assessed. Analyzing the results according to quartiles of age, significant differences were found for some parameters evaluated by the KDQOL-SF instrument, namely for work status, physical functioning and role-physical, which decreased with increasing age. We also found a higher proportion of diabetic patients, a decrease in creatinine, iron, albumin serum levels, transferrin saturation and nPCR, with increasing age. Moreover, significant negative correlations were found between age and mean cell hemoglobin concentration, iron, transferrin saturation, albumin, nPCR, work status, physical functioning and role-physical. In conclusion, our results showed that aging is associated with a decreased work status, physical functioning and role-physical, with a decreased dialysis adequacy, iron availability and nutritional status, and with an increased proportion of diabetic patients and of patients using central venous catheter, as the vascular access. The knowledge of these changes associated with aging, which have impact in the quality of life of the patients, could be useful in their management.

  18. 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

  19. 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

  20. 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.

  1. 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

  2. Unravelling Orbital Climatic Cycles from Devonian Magnetic Susceptibility Signal - The Quest for a Better Age Model for the Lochkovian and Pragian Stages (Czech Republic)

    NASA Astrophysics Data System (ADS)

    da Silva, A. C.; Chadimova, L.; Hladil, J.; Slavik, L.; Hilgen, F. J.; Dekkers, M. J.

    2015-12-01

    The uncertainties on the Devonian stage boundaries are currently in the order of several millions of years. When shown to reflect a detrital signal, which is influenced by climatic variations, Magnetic Susceptibility (MS) has been proven as a useful tool for identifying climatic cycles; which can subsequently be used to improve the time scale. Here, we focus on two sections from the Prague Synform (Czech Republic) cutting through the Lochkovian, Pragian and the lower part of the Emsian. Sedimentation is rhythmic, dominated by slightly clayey offshore limestones, being mostly calciturbidites and hemipelagites. We provide hysteresis analysis in order to get insight into the nature and the origin of the magnetic minerals driving the variation in the MS signal. The results point to a MS signal mostly carried by clay minerals. Subsequently, to improve estimation of the duration of the stages, we apply different spectral analysis techniques on this MS signal. From the Continuous Wavelet T