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B Vizmanos - One of the best experts on this subject based on the ideXlab platform.
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Body fat at pubertal Genital Stage 2: a comparison between Spanish and Mexican boys
European Journal of Clinical Nutrition, 2009Co-Authors: B Vizmanos, D Llop-viñolas, N Quezada-figueroa, M Sánchez-sucilla, J D Fernández-ballart, A L Salcedo-rocha, E M Vásquez-garibay, C Martí-hennebergAbstract:Background/Objectives: To compare body fat mass at the same Stage of pubertal maturation, Genital Stage 2 (G2), in a Spanish and in a Mexican sample of boys. Subjects/Methods: Data from Spain ( n =177) were from a previous longitudinal clinical follow-up and data from Mexico ( n =91) from a cross-sectional study. Subjects were grouped according to the presence of G2 at similar ages. Spanish sample was divided into boys with G2 at age 12 ( n =60), 13 ( n =74) and 14 ( n =43). In Mexican sample, 23 boys were at G2 at 12 years, 38 at age 13 and 30 at 14 years. Height, weight, upper arm circumference and four skinfold thicknesses were recorded. Genital development was assessed (Tanner scale). Sum of four skinfolds (SUM), body mass index (BMI), percentage of body fat (%BF) and extremity/trunk skinfold ratio (ETR=(triceps+biceps)/(subscapular+suprailiac)) was calculated. Results: When comparing subjects with different ages at G2 from the same country, or with the same age at G2 from different countries, no significant differences were found in adiposity variables (%BF, SUM), nor in BMI. Nevertheless, there were differences in body fat distribution: ETR was higher in Spanish boys ( P
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body fat at pubertal Genital Stage 2 a comparison between spanish and mexican boys
European Journal of Clinical Nutrition, 2009Co-Authors: B Vizmanos, D Llopvinolas, N Quezadafigueroa, M Sanchezsucilla, J Fernandezballart, A L Salcedorocha, Edgar M Vasquezgaribay, C MartihennebergAbstract:Background/Objectives: To compare body fat mass at the same Stage of pubertal maturation, Genital Stage 2 (G2), in a Spanish and in a Mexican sample of boys. Subjects/Methods: Data from Spain (n = 177) were from a previous longitudinal clinical follow-up and data from Mexico (n=91) from a cross-sectional study. Subjects were grouped according to the presence of G2 at similar ages. Spanish sample was divided into boys with G2 at age 12 (n=60), 13 (n = 74) and 14 (n=43). In Mexican sample, 23 boys were at G2 at 12 years, 38 at age 13 and 30 at 14 years. Height, weight, upper arm circumference and four skinfold thicknesses were recorded. Genital development was assessed (Tanner scale). Sum of four skinfolds (SUM), body mass index (BMI), percentage of body fat (%BF) and extremity/trunk skinfold ratio (ETR = (triceps + biceps)/(subscapular + suprailiac)) was calculated. Results: When comparing subjects with different ages at G2 from the same country, or with the same age at G2 from different countries, no significant differences were found in adiposity variables (%BF, SUM), nor in BMI. Nevertheless, there were differences in body fat distribution: ETR was higher in Spanish boys (P< 0.001), because of their greater triceps skinfold thickness (P=0.013), and due to the greater trunk fat stores in Mexican boys (P<0.01, subscapular and suprailiac skinfolds). Conclusions: There is a subcutaneous fat mass store characteristic of G2 in boys, which is not only independent of age, but is also observable in two different populations.
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Body fat at pubertal Genital Stage 2: a comparison between Spanish and Mexican boys.
European journal of clinical nutrition, 2008Co-Authors: B Vizmanos, D Llop-viñolas, N Quezada-figueroa, M Sánchez-sucilla, J D Fernández-ballart, A L Salcedo-rocha, E M Vásquez-garibay, C Martí-hennebergAbstract:Background/Objectives: To compare body fat mass at the same Stage of pubertal maturation, Genital Stage 2 (G2), in a Spanish and in a Mexican sample of boys. Subjects/Methods: Data from Spain (n = 177) were from a previous longitudinal clinical follow-up and data from Mexico (n=91) from a cross-sectional study. Subjects were grouped according to the presence of G2 at similar ages. Spanish sample was divided into boys with G2 at age 12 (n=60), 13 (n = 74) and 14 (n=43). In Mexican sample, 23 boys were at G2 at 12 years, 38 at age 13 and 30 at 14 years. Height, weight, upper arm circumference and four skinfold thicknesses were recorded. Genital development was assessed (Tanner scale). Sum of four skinfolds (SUM), body mass index (BMI), percentage of body fat (%BF) and extremity/trunk skinfold ratio (ETR = (triceps + biceps)/(subscapular + suprailiac)) was calculated. Results: When comparing subjects with different ages at G2 from the same country, or with the same age at G2 from different countries, no significant differences were found in adiposity variables (%BF, SUM), nor in BMI. Nevertheless, there were differences in body fat distribution: ETR was higher in Spanish boys (P< 0.001), because of their greater triceps skinfold thickness (P=0.013), and due to the greater trunk fat stores in Mexican boys (P
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Age of pubertal onset affects the intensity and duration of pubertal growth peak but not final height
American journal of human biology : the official journal of the Human Biology Council, 2001Co-Authors: B Vizmanos, C Martí-henneberg, Rosa Clivillé, Aurelia Moreno, Juan Fernández-ballartAbstract:This paper analyzed the intensity and duration of height growth during puberty in boys and girls in relation to rhythm of maturation. A longitudinal clinical follow-up between ages of 10 and 20 years, was carried out in a sample of 251 children grouped according to age at pubertal onset: boys (Genital Stage 2) at the ages of 11 (n = 28), 12 (n = 38), 13 (n = 42), and 14 (n = 27); and girls (breast Stage 2) at the ages of 10 (n = 37), 11 (n = 47), 12 (n = 19), and 13 (n = 13). Height was measured annually. Testicular volume and Genital development were assessed in boys, and breast development was assessed in girls. There were significant differences (P < 0.001) in height at the age of pubertal onset among maturity groups. Late maturers were taller than early maturers (r = 0.49, P < 0.001 for girls; r = 0.38, P < 0.001 for boys). However, final heights did not differ according to age of onset in either sex. In boys, later onset of puberty was associated with a smaller pubertal height gain (r = -0.60, P < 0.001) and a shorter period of pubertal growth (r = -0.61, P < 0.001). Equally in girls, earlier onset of puberty was associated with a greater pubertal height gain (r = -0.68, P < 0.001) and a longer period of pubertal growth (r = -0.59, P < 0.001). In conclusion, age of pubertal onset does not affect final height attained in both sexes, since there is an inverse compensatory phenomenon in both sexes between height at pubertal onset and the intensity and duration of pubertal growth.
C Martí-henneberg - One of the best experts on this subject based on the ideXlab platform.
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Body fat at pubertal Genital Stage 2: a comparison between Spanish and Mexican boys
European Journal of Clinical Nutrition, 2009Co-Authors: B Vizmanos, D Llop-viñolas, N Quezada-figueroa, M Sánchez-sucilla, J D Fernández-ballart, A L Salcedo-rocha, E M Vásquez-garibay, C Martí-hennebergAbstract:Background/Objectives: To compare body fat mass at the same Stage of pubertal maturation, Genital Stage 2 (G2), in a Spanish and in a Mexican sample of boys. Subjects/Methods: Data from Spain ( n =177) were from a previous longitudinal clinical follow-up and data from Mexico ( n =91) from a cross-sectional study. Subjects were grouped according to the presence of G2 at similar ages. Spanish sample was divided into boys with G2 at age 12 ( n =60), 13 ( n =74) and 14 ( n =43). In Mexican sample, 23 boys were at G2 at 12 years, 38 at age 13 and 30 at 14 years. Height, weight, upper arm circumference and four skinfold thicknesses were recorded. Genital development was assessed (Tanner scale). Sum of four skinfolds (SUM), body mass index (BMI), percentage of body fat (%BF) and extremity/trunk skinfold ratio (ETR=(triceps+biceps)/(subscapular+suprailiac)) was calculated. Results: When comparing subjects with different ages at G2 from the same country, or with the same age at G2 from different countries, no significant differences were found in adiposity variables (%BF, SUM), nor in BMI. Nevertheless, there were differences in body fat distribution: ETR was higher in Spanish boys ( P
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Body fat at pubertal Genital Stage 2: a comparison between Spanish and Mexican boys.
European journal of clinical nutrition, 2008Co-Authors: B Vizmanos, D Llop-viñolas, N Quezada-figueroa, M Sánchez-sucilla, J D Fernández-ballart, A L Salcedo-rocha, E M Vásquez-garibay, C Martí-hennebergAbstract:Background/Objectives: To compare body fat mass at the same Stage of pubertal maturation, Genital Stage 2 (G2), in a Spanish and in a Mexican sample of boys. Subjects/Methods: Data from Spain (n = 177) were from a previous longitudinal clinical follow-up and data from Mexico (n=91) from a cross-sectional study. Subjects were grouped according to the presence of G2 at similar ages. Spanish sample was divided into boys with G2 at age 12 (n=60), 13 (n = 74) and 14 (n=43). In Mexican sample, 23 boys were at G2 at 12 years, 38 at age 13 and 30 at 14 years. Height, weight, upper arm circumference and four skinfold thicknesses were recorded. Genital development was assessed (Tanner scale). Sum of four skinfolds (SUM), body mass index (BMI), percentage of body fat (%BF) and extremity/trunk skinfold ratio (ETR = (triceps + biceps)/(subscapular + suprailiac)) was calculated. Results: When comparing subjects with different ages at G2 from the same country, or with the same age at G2 from different countries, no significant differences were found in adiposity variables (%BF, SUM), nor in BMI. Nevertheless, there were differences in body fat distribution: ETR was higher in Spanish boys (P< 0.001), because of their greater triceps skinfold thickness (P=0.013), and due to the greater trunk fat stores in Mexican boys (P
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Age of pubertal onset affects the intensity and duration of pubertal growth peak but not final height
American journal of human biology : the official journal of the Human Biology Council, 2001Co-Authors: B Vizmanos, C Martí-henneberg, Rosa Clivillé, Aurelia Moreno, Juan Fernández-ballartAbstract:This paper analyzed the intensity and duration of height growth during puberty in boys and girls in relation to rhythm of maturation. A longitudinal clinical follow-up between ages of 10 and 20 years, was carried out in a sample of 251 children grouped according to age at pubertal onset: boys (Genital Stage 2) at the ages of 11 (n = 28), 12 (n = 38), 13 (n = 42), and 14 (n = 27); and girls (breast Stage 2) at the ages of 10 (n = 37), 11 (n = 47), 12 (n = 19), and 13 (n = 13). Height was measured annually. Testicular volume and Genital development were assessed in boys, and breast development was assessed in girls. There were significant differences (P < 0.001) in height at the age of pubertal onset among maturity groups. Late maturers were taller than early maturers (r = 0.49, P < 0.001 for girls; r = 0.38, P < 0.001 for boys). However, final heights did not differ according to age of onset in either sex. In boys, later onset of puberty was associated with a smaller pubertal height gain (r = -0.60, P < 0.001) and a shorter period of pubertal growth (r = -0.61, P < 0.001). Equally in girls, earlier onset of puberty was associated with a greater pubertal height gain (r = -0.68, P < 0.001) and a longer period of pubertal growth (r = -0.59, P < 0.001). In conclusion, age of pubertal onset does not affect final height attained in both sexes, since there is an inverse compensatory phenomenon in both sexes between height at pubertal onset and the intensity and duration of pubertal growth.
Anders Juul - One of the best experts on this subject based on the ideXlab platform.
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evaluation of 451 danish boys with delayed puberty diagnostic use of a new puberty nomogram and effects of oral testosterone therapy
The Journal of Clinical Endocrinology and Metabolism, 2015Co-Authors: Jacob Gerner Lawaetz, Jørgen Holm Petersen, Casper P. Hagen, Mikkel G. Mieritz, Martin Blomberg Jensen, Anders JuulAbstract:Context: Few data exist on the diagnostic criteria, and on the effects of puberty induction, in boys with constitutional delay in growth and puberty (CDGP). Objective: To develop puberty nomograms based on Danish boys with normal pubertal development. To evaluate the different diagnostic criteria and the effect of oral testosterone undecanoate (TU) in boys with CDGP. Design: A cross-sectional and longitudinal study of Danish boys with normal pubertal development (COPENHAGEN puberty study). A retrospective observational study of 451 boys evaluated for delayed puberty between 1990 and 2013. Setting: Tertiary referral center for pediatric endocrinology. Participants: One hundred and sixty-four (36%) boys evaluated for CDGP were excluded due to missing data, reclassification, or associated comorbidities, yielding 287 (64%) eligible for analysis. Main Outcome Measures: The number of patients with CDGP classified by the puberty nomogram (Genital Stage < −2 SD for age) versus the classical criteria (Genital stag...
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Elevated serum IGF-I, but unaltered sex steroid levels, in healthy boys with pubertal gynaecomastia.
Clinical endocrinology, 2013Co-Authors: Mikkel G. Mieritz, Annette Mouritsen, Casper P. Hagen, Lise Aksglaede, Kaspar Sørensen, Linda Hilsted, Anna-maria Andersson, Anders JuulAbstract:Objective Pubertal gynaecomastia is a very common condition. Although the underlying aetiology is poorly understood, it is generally accepted that excess of oestrogens and deficit of androgens are involved in the pathogenesis. Furthermore, adiposity as well as the GH/IGF-I axis may play a role. In this study, we elucidate the association of adiposity and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), testosterone, oestrogen, IGF-I and IGFBP-3 with the presence of pubertal gynaecomastia in a large cohort of healthy boys. Patients A total of 501 healthy Danish school boys (aged 6·1–19·8 year) from the COPENHAGEN Puberty Study. Measurements Anthropometry and pubertal Stages (PH1-6 and G1-5) were evaluated, and the presence of gynaecomastia was assessed. Body fat percentage was calculated by means of four skin folds and impedance. Nonfasting blood samples were analysed for FSH, LH, testosterone, SHBG, oestradiol, IGF-I, IGFBP-3 and prolactin. Results We found that 23% (31/133) of all pubertal boys had gynaecomastia. More specifically, 63% (10/16) of boys in Genital Stage 4 had gynaecomastia. Boys with gynaecomastia had significantly higher IGF-I levels compared with controls (IGF-I SD-score 0·72 vs −0·037, P
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The pubertal transition in 179 healthy Danish children: associations between pubarche, adrenarche, gonadarche, and body composition
European journal of endocrinology, 2012Co-Authors: Annette Mouritsen, Jørgen Holm Petersen, Katharina M. Main, Casper P. Hagen, Lise Aksglaede, Kaspar Soerensen, Anders JuulAbstract:Background: Pubertal onset is usually defined by breast development in girls and testicular growth in boys. Pubarche is defined as the attainment of pubic hair and is considered as a sign of pubertal transition. Pubarche is preceded by a gradual increase in production of adrenal androgens, DHEA and D4-androstenedione (Adione), a process termed adrenarche. Objective: To study the natural course of pubertal transition and the associations with adrenarche, body fat, and linear growth. Design and methods: A longitudinal study of 179 healthy children (89 girls) with higher socioeconomic background examined every 6 months for 5 years. Pubic hair Stage, breast Stage, Genital Stage, testicular volume (TV), height, weight, and four skinfolds were measured. Results: In girls, median age (25th and 75th percentiles) at thelarche (B2C) was 10.1 years (9.3‐10.9). In boys, median age at attaining a TV O3 ml was 11.5 years (10.9‐12.0). Median age at pubarche (PH2C) was 10.9 years (10.3‐11.4) in girls and 11.6 years (10.8‐12.4) in boys. Only 6.8% (4/59) of the girls and 24.6% (15/61) of the boys developed pubic hair as the first isolated sign of puberty. Serum DHEAS and Adione increased with age, although the increase in Adione was most pronounced in girls. No associations between early age at thelarche/testicular growth and increased body fat (BMI and sum of four skinfolds) were observed. Conclusion: Danish children rarely experience pubarche as the first sign of puberty. No associations between age at pubertal onset and body composition were found. Circulating levels of Adione, but not DHEAS, increased with the onset of puberty, although with large interindividual variability.
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Pubertal development in Danish children: comparison of recent European and US data
International journal of andrology, 2006Co-Authors: Anders Juul, Katharina M. Main, Grete Teilmann, Thomas H. Scheike, N T Hertel, Kirsten Holm, E M Laursen, Niels E SkakkebaekAbstract:Two recent epidemiological studies (PROS and NHANES III) from the USA noted earlier sexual maturation in girls, leading to increased attention internationally to the age at onset of puberty. We studied the timing of puberty in a large cohort of healthy Danish children in order to evaluate differences between USA and Denmark, as well as to look for possible secular trends in pubertal development. Healthy Caucasian children from public schools in Denmark participated in the study which was carried out in 1991-1993. A total number of 826 boys and 1,100 girls (aged 6.0-19.9 years) were included, and pubertal Stages were assessed by clinical examination according to methods of Tanner. In boys testicular volume was determined using an orchidometer. We found that age at breast development 2 (B2) was 10.88 years, and mean menarcheal age was 13.42 years. Girls with body mass index (BMI) above the median had significantly earlier puberty (age at B2 10.42 years) compared with girls with BMI below the median (age at B2 11.24 years, p < 0.0001). Similarly, menarcheal age was significantly lower in girls with BMI above the median compared with girls with BMI below the median (13.12 vs. 13.70 years, p = 0.0012). In Danish boys we found that age at Genital Stage 2 (G2) was 11.83 years. Both sexes were significantly taller compared with data from 1964, but timing of pubertal maturation seemed unaltered. Finally, puberty occurred much later in Denmark compared with recent data from USA. We could not detect any downwards secular trend in the timing of puberty in Denmark between 1964 and 1991-1993 as seen in the US. Obesity certainly plays a role in the timing of puberty, but the marked differences between Denmark and USA cannot be attributed exclusively to differences in BMI. A possible role of other factors like genetic polymorphisms, nutrition, physical activity or endocrine disrupting chemicals must therefore also be considered. Therefore, we believe it is crucial to monitor the pubertal development closely in Denmark in the coming decades.
D. A. Price - One of the best experts on this subject based on the ideXlab platform.
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Serum leptin through childhood and adolescence.
Clinical endocrinology, 1997Co-Authors: Peter E. Clayton, Matthew S. Gill, Catherine M. Hall, Vallo Tillmann, Andrew Whatmore, D. A. PriceAbstract:OBJECTIVE Leptin is the protein product of the recently cloned ob gene, that has been implicated in the control of body weight and thermogenesis, but also independently stimulates the reproductive axis. As major changes in body composition and gonadal function occur during human adolescence, we have assessed serum leptin concentration through childhood. SUBJECTS AND MEASUREMENTS Serum leptin was measured in a radioimmunoassay in samples from 235 healthy children from 5 to 18 years of age. Its relationship to body mass index (BMI) (expressed as standard deviation score (SDS)) and the changes in concentration both within and between sexes over the Stages of puberty were analysed. RESULTS Serum leptin was present at similar concentrations in both sexes over the prepubertal years and increased in parallel into early puberty (breast Stage (B) 2, Genital Stage (G) 2). Thereafter serum leptin in the boys declined to a nadir in G5. In contrast in girls, leptin remained constant in mid-puberty rising to a peak at B5. Factors influencing leptin (BMI SDS, age and testicular volume) were assessed therefore in the pre- and peripubertal Stages (B1–2, G1–2) compared to the later pubertal Stages (B3–5, G3–5). In all groups, leptin was positively correlated to BMI SDS (r2=38–41% in girls, r2=31–35% in boys). However in B1–2 and G1–2, leptin was also positively related to age, which contributed a further 27% and 20% respectively to the variability. In B3–5, age only accounted for an additional 5% in leptin variability. In contrast in G3–5, leptin was related positively to BMI SDS (r2=35%) and negatively to testicular volume (r2=24%). CONCLUSIONS The influence of BMI on leptin is a significant factor throughout the prepubertal and pubertal years of both sexes. The additional negative effect of testicular volume in the boys contributes to the sexual dichotomy in leptin concentration at the completion of puberty. The similar rise in leptin over the prepubertal years into early puberty in both sexes, related not only to BMI SDS but also independently to age, would suggest that leptin may have a facilitatory role in human pubertal development.
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The influence of age, size, pubertal status and renal factors on urinary growth hormone excretion in normal children and adolescents.
Growth regulation, 1992Co-Authors: A. M. Skinner, D. A. Price, G. M. Addison, Peter E. Clayton, R. I. Mackay, A. Soo, C. Y. W. MuiAbstract:Overnight urinary growth hormone (GH) excretion was measured in 528 schoolchildren (aged 4-16 years) whose heights and weights were between the third and 97th centiles. Urinary GH increased significantly with age, reaching a maximum in boys at 15-years-old and in girls at 13-years-old. Peak levels were five and three times higher in boys and girls respectively than in 4-year-olds. Maximum urinary GH excretion was seen at breast Stages 3 and 4 in girls and at Genital Stage 4 in boys followed by a decline in both sexes at Stage 5. Boys excreted more GH than girls during prepubertal and pubertal years. During prepubertal years there were fluctuations of urinary excretion of GH with age. Height, weight and pubertal status predicted 31% of the variability of urinary excretion of GH, and urinary excretion of creatinine, albumin and N-acetylglucosaminidase (NAG) predicted 52% of the variability. The importance of establishing sound age and sex-related reference ranges for urinary growth hormone is stressed before application of this test to children with growth disorders.
Martin O. Savage - One of the best experts on this subject based on the ideXlab platform.
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The effect of recombinant human insulin-like growth factor-I treatment on growth hormone secretion in two subjects with growth hormone insensitivity (Laron syndrome).
Clinical endocrinology, 1993Co-Authors: A. M. Cotterill, Cecilia Camacho-hübner, Jeffrey M P Holly, Martin O. SavageAbstract:Summary OBJECTIVE Growth hormone (GH) secretion Is increased in conditions of GH insensitivity such as Laron syndrome, with elevation of both basal and peak levels. We have studied the effect of recombinant IGF-I therapy on the pattern of GH secretion in two subjects with GH insensitivity. SUBJECTS Two pubertal subjects with GH insensitivity (female, 16.4 years, breast Stage 3; male 13.6 years, Genital Stage 2) were investigated after 6 months of IGF-I therapy (120 μg/kg twice daily s.c. at 0800 and 1900 h). GH profiles taken before the start of IGF-I therapy, when both subjects were prepubertal (aged 14 0 and 11 5 years respectively), were used for comparison. METHODS GH profiles were performed with blood samples taken every 20 minutes between 2000 and 0800 h from an indwelling cannula. MEASUREMENTS Serum samples were assayed for GH by immunoradiometric assay and IGF-I, IGFBP-1 and insulin by radioimmunoassay. RESULTS Before IGF-I therapy, GH profile studies demonstrated pulsatile GH secretion. Basal GH was elevated with no value falling below the limit of detection of the assay and an increase in peak levels (maximum 203 and 206 μ/I at 0000 h and 0020 h respectively). After 6 months IGF-I therapy, the GH profiles were significantly different. With the onset of puberty a further increase in GH secretion would have been expected; nevertheless, following administration of IGF-I at 1900 h, GH secretion decreased with a reduction in mean overnight GH levels from 65 to 33 μ/l and 53 to 11 μ/l respectively. GH pulsatility was also suppressed in the two subjects, for the first 3.5 and 6 hours overnight respectively. Pulsatile GH secretion then returned with peak levels reaching 130 and 63 μ/l respectively. Prior to therapy IGF-I levels were at the lower limit of assay detection. On IGF-I therapy serum IGF-I levels reached a peak within 3 hours (298 and 438 μg/l) coinciding with the suppression of GH secretion. IGF-I levels fell rapidly overnight to 92 and 101 μg/l at 0800 h prior to the next injection. The fall in serum IGF-I coincided with the return of GH secretion. IGFBP-1 levels increased overnight both before and during IGF-I therapy, rising from 24 to 83 and 22 to 110 μg/l before therapy and 13 to 60 and 13 to 71 μg/l during therapy. This rise in IGFBP-1 appeared to be inversely related to the fall in serum insulin levels overnight and appeared not to be affected by IGF-I therapy. CONCLUSION GH secretion is suppressed by exogenous IGF-I therapy in GH insensitive subjects. The failure to maintain high serum IGF-I levels overnight, presumably due to a persisting defect in serum IGFBP-3 levels, was associated with an early return of GH secretion. These findings may have implications for the dose and regimen of IGF-I therapy in subjects with growth hormone insensitivity.