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PubMed1980

[Sex characteristics of the anatomy of the superior mesenteric lymph nodes in an adult].

In 60 corpses of grown-up persons at the age of 21-90 years the number, size and form of the superior mesenteric lymph nodes and their vessels have been investigated. The lymph nodes in question, their afferent and deferent vessels have been revealed by means of interstitial injection of coloured masses into the small intestine wall, and subsequent injection of the lymph nodes situated in the mesentery. Certain sex differences have been revealed in the number, size and form of the superior mesenteric lymph nodes and their vessels.

Adult↗
PubMed1980

Secondary sex characteristics of girls 12 to 17 years of age: the U.S. Health Examination Survey.

Data from the United States Health Examination Survey, Cycle III, were used to describe the relationships among secondary sexual characteristics, bone age, and body mass index of girls aged 12 to 17 years. The survey examined a sample of girls representative of the American population with respect to race, age, geographic region, and socioeconomic status. Tanner stages for breast and pubic hair development correlated closely. There was also a close relationship between Tanner rankings of sexual maturity and both bone age and body mass index (weight/height). Socioeconomic status was not related to sexual development, but there were significant racial and geographic differences in the age of development of secondary sexual characteristics. The Health Examination Survey data provide standards of sexual and physiologic growth for U.S. girls.

Adolescent↗
PubMed1990

[Development of sex characteristics in relation to nutritional status].

Results of anthropometric measurements and determination of the state of sexual maturation in 8703 girls and 8685 boys aged between 8-16 years show that, if these results are related to the nutritional state, the development of the signs of sexual maturity is dependently on the nutritional state.

Adolescent↗
PubMedDate not supplied

[Development of sex characteristics in adolescents in the forest regions of Ukraine].

A total of 3019 adolescents were examined residing in those territories of the Zhitomir and Vinnitsa Regions affected by radionuclide contamination, who ranged from 15 to 18 years old. Revealed in the above juvenile population was a stimulating effect of small doses of ionizing radiation on some parameters characterizing somatosexual development in adolescents 15 years old, that tends to smooth down with stabilization of physical and sexual development.

Adolescent↗
PubMed1979

[Hormonal regulation and hormone therapy in childhood and adolescence. Part 1: development of endocrine glands, hormone production, menarche and secondary sex characteristics].

The growth curves of the endocrine glands in female puberty are described. Adrenarche with an elevated production of adrenal dehydroepiandrosterone marks the beginning of prepuberty. By decrease of hypothalamic sensitivity to sexual steroids begins the deviation of FSH and LH levels. Significant increases of gonadotrophins and prolactin occur during sleep. There is a good correlation between bone age, Tanner-stages of breast and pubic hair development and steroid hormone levels. Criteria of maturity for young girls including menarche and ovulation are given.

Adolescent↗
PubMed1986

Fundamental voice frequency measured by electroglottography during continuous speech. A new exact secondary sex characteristic in boys in puberty.

The variation of fundamental voice frequency measured by the average of 2000 consecutive electroglottographic cycles in a reading situation has been examined in relation to pubertal development and androgens. Fundamental frequency among other parameters was related to height (r -0.82), pubic hair stage (r -0.87), testis volume (r -0.78), total testosterone (r -0.73) and serum hormone binding globulin (r 0.75). Single observations of fundamental frequency show a clear grouping of results under and over 200 Hz. Fundamental frequency of more than 200 Hz and serum testosterone of more than 10 nmol/l probably represent values for a boy in puberty. There seem to be comparable relations with other androgens and with serum hormone binding globulin.

Adolescent↗
PubMed1991

[Sexual development: development of secondary sex characteristics--Tanner stages 25 years later].

In a longitudinal study the british pediatrician J.M. Tanner evaluated the development of breasts (thelarche), of pubic hairs (pubarche) and age of menarche. In Hungary we did a similar evaluation in 680 girls in the years 1980 to 1986. Comparing these data in a cross-sectional study with similar data from Münster we named the results central-european study. The results are similar the Tanner ones exceptionally the duration of breast development, which was shorter than in the hitherto published longitudinal studies. Mean age of menarche in our study was 12.5 years compared with 13.5 years in the former ones. This is not a confirmation to acceleration of puberty, because in other countries age of menarche was stabile. Additionally, to thelarche, pubarche and menarche we collected data about axillarche.

Adolescent↗
PubMed1975

[Influence of temperature on the rate of spermatogenesis, duration of spermatogenic activity and development of secondary sex characteristics in the wall-lizard, Lacerta muralis L. (Reptilia, Lacertidae)].

A series of experiments was carried out primarily between the 22nd of March and the 27th of June, on 60 Lacerta muralis maintained either under semi-natural conditions in large enclosures or in constant-temperature cabinets maintained at 17.5 degrees C, 20 degrees C, 22.5 degrees C and 27.5 degrees C with a natural photoperiod. Following an injection of tritiated thymidine, the animals were sacrificed at regular intervals and the rate of spermatogenesis was deduced from the progression of the radioactive front in the seminiferous epithelium. The following results were obtained: 1. The rate of spermatogenesis is temperature dependent and increases by a factor of approximately 1.2 per degree centigrade between 17.5 and 27.5 degrees C. The rate is seven times greater at 27.5 degrees C than at 17.5 degrees C. 2. Under semi-natural conditions the interval leptotene-spermatozooid lasts 70 days, slightly less than that found at a constant temperature of 22.5 degrees C. 3. Under semi-natural conditions the rate of spermatogenesis was similar to that in August-September, April-May and May-June which indicates that the lizards were able to maintain their body temperature at an equivalent level by behavioural temperature regulation during the greater part of their activity period. 4. Under semi-natural conditions, or at temperatures in excess of 22 degrees C, spermiogenesis lasts 1.8 times as long as meiosis. 5. At constant temperatures lower than 21 degrees C the development of the cellular lineage is aressted at the young spermatid stage. 6. Constant temperatures between 17.5 and 22.5 degrees C had no effect on the time of involution of the testis at the start of summer. 7. At low constant temperatures, secondary sexual characteristics regress before the usual time: after 4 weeks at 20 degrees C and after 8 weeks at 17.5 degrees C. An expected regression after 8 weeks produced after exposure to a temperature of 22.5 degrees C is probably due to factors other than temperature. 8. In the case of different individuals kept either under natural, semi-natural or experimental conditions, there was no close relationship observed between the time of involution of the seminiferous tubules and regression of secondary sexual characters. ters. 9. These results confirm the concept of endogenous control of sexual regression at the commencement of summer and argue in favour of 2 separate gonadotrophic hormones in reptiles.

Animals↗
PubMed2006

[Sex characteristics of neuroendocrine effects of prenatal exposure to exogenous glucocorticoids].

The effects of hydrocortisone acetate treatment of rats during the last gestational week on neurochemical and morphological characteristics of the brain in early postnatal and mature offspring were studied. Disappearance of sexual differences both in aromatase and 5alpha-reductase activities and noradrenaline concentration in the preoptic area in 10-day old rats was found. Meanwhile a sexual dimorphism in serotonin metabolism emerged. In adult offspring, the prenatal exposure to glucocorticoids resulted in disappearance of sexual differences in neurocytes' nuclei volume in medial preoptic and suprachiasmatic nuclei. The adrenocortical reaction to noradrenaline infusion to the 3rd brain ventricle was absent in the experimental males and intensified in females. In males, adrenocortical reaction to restraint decreased while post-stress changes in hypothalamic noradrenaline concentration and hippocampal glutamate decarboxylase activity were not observed. In the similar experiments in females both the augmentation of adrenocortical reaction and inhibition of GABA-ergic system were revealed. The results obtained indicate the modifying effect of prenatal exposure to glucocorticoids on sexual dimorphism of neuroendocrine system.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1996

Serum testosterone, 5-alpha-dihydrotestosterone and different sex characteristics in male fallow deer (Cervus dama): a long-term experiment with accelerated photoperiods.

To investigate the photoperiodic influence on androgen, testis volume, neck girth, and antler-cycles, five fallow bucks were exposed consecutively to different accelerated photoperiodic cycles (three 6-month, three 4-month, and one 3-month cycle). All parameters immediately followed artificial light cycles. Unlike in natural conditions, antler casting, regrowth, and velvet shedding occurred at decreasing day-lengths. The experiment provided further evidence that in fallow bucks the reproductive system is under strictly photoperiodic control and directly and/or indirectly dictates the course of the antler cycle via gonadal hormones. Depending on the test-system, the experiment revealed similar threshold values for the effect of testosterone (T) and/or 5-alpha-dihydrotestosterone (DHT) concentrations on the antler cycle as previously detected in fallow bucks living under natural conditions. Antlers were cast when T levels dropped below 3 ng/ml, and velvet shedding occurred after T and/or DHT values reached at least 5 to 7 ng/ml. In all cases, amplitudes of androgens remained lower than observed under natural conditions. Frequently during early antler growth, DHT values appeared higher than T levels. With increasing acceleration of the photoperiod, the antler cycle achieved limits of adaptation. The faster the photoperiods were accelerated, the smaller the antlers were developed. In addition, the antler tips were porous, blunt, and not completely mineralized. In all animals, accelerations of the photoperiods evoked phase displacements between measured parameters, pointing to an increasing internal desynchronisation. The present results indicate that the whole reproductive system of fallow deer is directly controlled by the photoperiod and that related morphological and physiological processes are indirectly determined by photoperiodic changes.

Animals↗
PubMed1992

Secondary sex characteristics and related physiological values in male fallow deer (Dama dama L.) and their relationships to changes in the annual cycle of daylengths: frequency alterations to 4- and 3-month photoperiodic cycles, and subsequent re-synchronisation under natural conditions.

Five adult male fallow deer were maintained in a barn with artificial light control. In a previous experiment, three 6-month photoperiodic cycles entrained morphogenetic and associated physiological values that revealed typical relationships to the antler cycle. Presented here, the light cycle was accelerated to three 4- and one 3-month photoperiods in the same group. Each artificial photoperiod generally resulted not only in an almost complete antler cycle but also in an entire cycle of seasonal fluctuations in neck girth. Increases in plasma levels of alkaline phosphatase (AP), total-, LDL- and HDL-cholesterol, were generally entrained and the maxima revealed positive correlations with antler formation, but the relationships slightly diverged. In neck girth and creatinine, positive correlations to the hard antler period as well as to each other prevailed but diverged. In the 3-month photoperiodic cycle, these relationships were out of synchrony. In the second 4-month cycle, two bucks "missed" shedding and subsequent casting, but commenced antler growth in the following cycle with an in-time shedding. The possibility of desynchronisation of physiological conditions and the question of an endogenous circannual mechanism interacting with daylight are discussed. At the end of the 3-month cycle, experimental indoor and natural outdoor casting was coincident so the group was transferred to outside conditions for re-synchronisation. After spending altogether 36 months in frequency altered photoperiods, the represented values were neither synchronized nor revealed their typical relationships to the antler cycle, except of AP and neck volume. In the second cycle of re-synchronisation, all parameters, except of creatinine, appeared to be resynchronized.

Alkaline Phosphatase↗
PubMed2002

Ethnic differences in the presence of secondary sex characteristics and menarche among US girls: the Third National Health and Nutrition Examination Survey, 1988-1994.

OBJECTIVE: To assess measures of puberty-presence of pubic hair, breast development, and menarche-for 3 racial/ethnic groups of girls in the United States. METHODS: Using data from the Third National Health and Nutrition Examination Survey, this study sample was restricted to 1623 girls aged 8 to 16 years (466 non-Hispanic white, 589 non-Hispanic black, and 568 Mexican American) for whom information was available on Tanner stages of pubic hair and breast development. Subsequently, the sample was restricted to 1168 girls aged 10 to 16 years (330 non-Hispanic white, 419 non-Hispanic black, and 419 Mexican American) for whom menarche data were available. Tanner stage II or higher was used to define pubic hair and breast development; menarche status was self-reported. The percentage of girls who had pubic hair and breast development and had achieved menarche was computed by age and race/ethnicity. Probit and failure time models were applied to estimate mean ages at onset of pubic hair, breast development, and menarche. The racial/ethnic differences also were examined after adjustment for social and economic variables and current body mass index. RESULTS: Black and Mexican American girls had pubic hair and breast development and had achieved menarche at younger ages than white girls. For example, 49.4% of black girls aged 9 years had breast development compared with 24.5% of Mexican American girls and 15.8% of white girls. The mean age at onset of pubic hair, breast development, and menarche was 9.5, 9.5, and 12.1 year for black girls; 10.3, 9.8, and 12.2 years for Mexican American girls; and 10.5, 10.3, and 12.7 years for white girls. These ethnic differences remained even after adjustment for current body mass index and several social and economic variables. CONCLUSION: Black girls on average enter puberty first, followed by Mexican American and then white girls.

Adolescent↗
PubMed1998

Five minute recordings of heart rate variability for population studies: repeatability and age-sex characteristics.

OBJECTIVE: To evaluate the stability of short recordings of heart rate variability (HRV) with time, and the association of HRV with age and sex. DESIGN: Five minute Holter recordings were made twice over a two month interval (tracking study). In addition, HRV was measured in a cross sectional study. SETTING: Residents of 11 Israeli kibbutzim were examined in their settlements. SUBJECTS: 32 men and 38 women (aged 31-67) participated in the tracking study and 294 (aged 35-65) were involved in the cross sectional study. MAIN OUTCOME MEASURES: Time and frequency domain analyses on Holter recordings were undertaken in two breathing conditions: spontaneous and controlled breathing (15 respirations per minute). Regression was used to assess the relations of sex, age, heart rate, and logarithmically transformed HRV indices. RESULTS: HRV measures were highly consistent with time with correlations of 0.76-0.80 for high frequency and total power. Geometric mean total power declined with age by 45% in men and 32% in women, and was lower by 24% among women than among men (all p < or = 0.005). Men had a 34% higher very low and low frequency power and a higher ratio of low to high frequency power (p < 0.001). Conversely, high frequency power in women represents a greater proportion of total power than in men. CONCLUSION: Short recordings of HRV in a non-laboratory setting are stable over months and therefore characteristic of an individual. Strong age and sex effects were evident. HRV derived from short recordings can be informative in population based studies.

Adult↗