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Adolescent development in males with Down syndrome.

We investigated growth features, development of primary and secondary sex characteristics, and specified pituitary and testicular hormone levels in 46 male adolescents and young adults with Down syndrome. Their mean height age was significantly less than and their mean bone age was slightly more than their chronological age. The subjects' secondary sex characteristics followed the same developmental pattern noted in youngsters without Down syndrome. Penile length and circumference and testicular volume of our patients with Down syndrome were not statistically different from those of normal adolescents. Follicle-stimulating hormone, luteinizing hormone, and testosterone levels in our study population were similar to those reported for normal adolescents during sexual maturation.

Adolescent↗

Macro-orchidism in juvenile hypothyroidism.

A boy, aged 16 years, with absence of development of the secondary sex characteristics, inappropriately large testes for his stage of puberty, and short stature is described. The symptoms were secondary to long-standing prepubertal hypothyroidism. Following therapy with thyroxine, there was a rapid advancement in growth velocity, full development of the secondary sex characteristics, and reduction in the size of the testes.

Adolescent↗

Sexual development and behavior in black preadolescents.

As part of a longitudinal study of the sociosexual development of black preadolescents, sexual maturation and sociosexual behaviors were assessed and the relationships between these variables determined in a sample of 101 nine- to eleven-year-old middle- and low-income boys and girls. Sexual maturation was measured by Tanner's staging criteria of specific secondary sex characteristics. Involvement in heterosexual behaviors was elicited via self reports and was classified on a five-point heterosexual physical activity scale (HPA). The data corroborate other studies in demonstrating that girls were more advanced than boys in the process of sexual maturation. Considerable variation in stages of maturation for chronological age existed in both boys and girls, but was more pronounced for girls. In girls, there was no significant association between HPA and degree of biologic maturation. However, genital development in boys was significantly related to their sexual behavior. Income level was not significantly associated with the HPA score. A baseline from which to chart the progress of sociosexual behaviors in these developing preadolescents was established.

Black or African American↗

The autistic child's recognition of age- and sex-related characteristics of people.

Matched autistic, normal, and nonautistic retarded children were tested for their ability to choose schematic and photographed faces of a man, a woman, a girl, and a boy, to accompany videotaped sequences depicting a person of each class in (a) gestures, (b) vocalizations, and (c) "contexts" that might be considered typical for an individual of this age and sex. Although both autistic and control subjects were able to choose drawings of nonpersonal objects to correspond with videotaped cues, the autistic children were markedly impaired in selecting appropriate faces for the videotaped individuals. It is suggested that these results may reflect autistic children's relative disability in differentiating adults from children and males from females.

Adolescent↗

Parent characteristics and sex differential infant mortality: the case in Tennessee.

Females survive males at most ages in virtually all modern industrialized societies. However, stratification of a sample by socioeconomic indicators shows that white infant male and female postneonatal mortality rates converge as the mothers' or parents' education rises and as the mothers age. These results are congruent with the parental selection hypothesis and with other findings that suggest that families at the pinnacle of the local social structure invest heavily in males and that parents nearing the end of their reproductive career try hard to effect the survival of all offspring.

Educational Status↗

Exposure to sublethal levels of waterborne lead alters reproductive behavior patterns in fathead minnows (Pimephales promelas).

Lead (Pb) caused multiple effects on reproductive behavior and overall reproductive success. Adult fathead minnows (Pimephales promelas) were acclimated at a 16L:8D photoperiod to stimulate reproductive development. Reproductively mature adults were separated as male-female pairs and maintained for 4 weeks in either 0.0 or 0.5 ppm Pb. High lead accumulations occurred in testes and ovaries of treated fish; lead concentrations in control fish gonads were not detectable. Lead suppressed spermatocyte production and retarded ovarian development, although no lead-induced gonadosomatic index changes for either sex were noted. Lead decreased the number of eggs oviposited, increased interspawn periods and suppressed embryo development. Control males displayed maximum secondary sex characteristic development (banding, tubercle formation, head and eye darkening); lead-exposed fish displayed less. Control males spent more time in ceiling-directed behaviors associated with nest preparation and maintenance than lead-exposed. These variables were affected differentially with respect to stage of reproductive maturity at time of lead exposure, i.e., fish displaying greater secondary sex characteristic development before exposure were less affected by lead than those fish that showed less development.

Animals↗

[Characteristics of sex behavior of men in Mexico City].

OBJECTIVE: To determine the major features of sexual behavior in men from Mexico City, such as the number of sexual partners, history of sexually transmitted disease (STD) and beliefs on AIDS. MATERIAL AND METHODS: A transversal epidemiologic study was conducted in 1995 based on multistage sampling with conglomerates. A total of 1,377 males from 15 to 49 years of age was interviewed by means of a structured questionnaire. Statistics such as Student's test and chi 2 were applied to determine significance. RESULTS: Subject mean age was 17.7 years (SD = 2.8 years) Overall proportion of condom use in the last intercourse was 24.6% depending on the type of partner: 18.8% used it with regular partners and 62.5% with multiple partners. Symptoms suggesting gonococcal uretritis were found in 2%. Finally, 97.5% understood the meaning of AIDS and knew some protective measures against infection. CONCLUSIONS: Some risky characteristics of sexual behavior were identified concerning the transmission of STD such as multiple sexual partners, not using condom and STD antecedents.

Acquired Immunodeficiency Syndrome↗

Suppression of aromatase activity in populations of bream (Abramis brama) from the river Elbe, Germany.

Aromatase activity was determined in brain and gonads of wild bream collected along the river Elbe, Germany, and correlated with other endocrine and reproductive endpoints such as plasma sex steroid concentrations, secondary sex characteristics (STI), plasma vitellogenin, gonad size (GSI), and maturation stages of germ cells (MS) that were reported for the same fish in a previous study. Furthermore, regional patterns of aromatase activity were correlated to a number of environmental factors such as exposure to environmental contaminants and parasitism. While aromatase activity was not detectable in the gonads of male and female fish with the assay used, fish of both genders revealed relatively great brain enzyme activities. As for most of the endocrine and reproductive parameters, with the exception of plasma testosterone (T), aromatase activities were significantly less in fish from a river stretch characterized by elevated exposures to organic contaminants and metals. Brain aromatase activity was positively and significantly correlated with plasma estradiol (E2) and MS in females, and showed a similar trend with plasma 11-ketotestosterone (11KT) and STI in males. No comparable trend occurred for T. This decrease of the reproductively relevant hormones 11KT and E2 may be indicative of a disruption of the last step in sex hormone synthesis, a hypothesis that was supported for E2 by the strong (R2=0.78, p<0.05) linear regression between aromatase activity and E2 in female bream. It is also hypothesized that the effects on brain aromatase activity were likely to be related to the disruption of other reproductive parameters including sexual maturity and expression of secondary sex characteristics. Although a number of factors such as exposure to pollutants and prevalence of the tapeworm Ligula intestinalis correlated with the suppression of aromatase activity, the exact causes for the regional decrease in brain aromatase activity remain unclear due to inconsistencies of these correlations between sampling events or gender.

Animals↗

[The effect of treatment on growth in children with central precocious puberty].

BACKGROUND: Modern treatment of central precocious puberty (CPP) by agonist analogues of gonadoliberin (aGnRH) block the development of secondary sex characteristics, it delays bone maturation and improves the prospects of reaching optimal height. The objective of the present study was to compare the effect of formerly used treatment with synthetic progestin, Cyproterone acetate (Androcur, Schering), with contemporary treatment using aGnRH Triptoreline (D-Trp-6-LHRH, Decapeptyl depot, Ferring) on growth parameters of female patients. METHODS AND RESULTS: The authors treated 12 girls with CPP. The first group comprised 7 girls treated solely with Cyproterone acetate (first signs of CPP at the age of 4.9 +/- 1.8 years, onset of study at calendar age (CA) 7.1 +/- 1.3 years, bone age (BA) 10.2 +/- 1.3 years, follow-up period 1.8 +/- 0.8 years). The second group was formed by five girls originally treated for a period of 1.8 +/- 1.7 years (4-56 months) with Cyproterone acetate and subsequently with Triptoreline for a period of 1.5 +/- 0.3 years. The latter group developed signs of CPP at the age of 4.9 +/- 2.6 years. At the onset of Triptoreline treatment and thus at the onset of the study the girls' age was 7.4 +/- 0.7 years and BA 9.6 +/- 1.9 years. Secondary sex characteristics did not progress in either of the investigated groups during the study period. The authors observed in both groups before the investigation an acceleration of BA per calendar year (dBA/CA) of 1.5 +/- 0.6 SD (p < 0.01), as compared with standards of the healthy population. In the course of the investigation in the first group dBA/CA of 1.4 +/- 0.6 years (p < 0.01) persisted, in the second group a decline of dBA/CA to a normal level occurred (0.9 +/- 0.4 years). The growth rate in the two groups did not differ during the investigation from standards for the healthy population. Height in relation to bone age (BH/BA SDS) declined in the first group during the investigation from -1.8 +/- 0.9 SDS to -2.2 +/- 1.0 SDS (p = 0.06). In the second group this indicator did not change. CONCLUSIONS: During Triptoreline treatment, as compared with Cyproterone acetate treatment, in patients with CPP the rate of bone maturation declined to normal and their height in relation to bone age did not decline. This led to the assumption of a smaller future adult height loss in patients treated with aGnRH Triptoreline.

Child↗

Ejaculatory duct obstruction in the infertile male: experience of 7 cases at Ramathibodi Hospital.

OBJECTIVE: To study the clinical presentations, management, outcomes as well as pregnancy rate of ejaculatory duct obstruction treated at the Division of Urology, Ramathibodi Hospital. MATERIAL AND METHOD: This retrospective study was done from 1980 to 1999 and information from the medical records of the patients of ejaculatory duct obstruction was obtained. Phone and mail were used for long-term follow-up. RESULTS: Seven male patients with ejaculatory duct obstruction were identified. The age ranged from 32-45 years old (mean 34.5). All of the patients had azoospermia without other symptoms related to ejaculatory duct obstruction such as painful ejaculation, perineal or testicular pain. Normal testicles and secondary sex characteristics were noted in all. Seventy-one per cent had normal hormonal profiles and twenty-nine per cent had a slight increase of FSH, LH but not more than one fold of normal range. Vasography was used as the diagnosis tool in all of the cases and 71 per cent of seminal vesicles were >1.5 cm in diameter and all the rest were 1 cm in diameter. Transurethral resection of ejaculatory duct (TURED) was done in 6 cases and transurethral incision of ejaculatory duct (TUIED) was done in 1 case. Semen analysis was done in the third month after operation and 4 of 7 (57%) showed improvement of semen analysis but another 3 cases (43%) still had azoospermia. Six months after operation 6 of 7 (86%) showed improvement of semen analysis. Up to one year, 6 of 7 (86%) have normal semen analysis and another one still had azoospermia. In the long-term follow-up, 4 of 7 (57%) were able to impregnate their wives. CONCLUSIONS: Ejaculatory duct obstruction is a treatable cause of male infertility. In an infertile male with oligospermia or azoospermia with low ejaculate volume, normal secondary sex characteristics, testes and normal hormonal profiles, ejaculatory duct obstruction is suggested. Transrectal ultrasonography (TRUS) and/or vasography can be done to confirm the dilatation of seminal vesicles and obstruction of the ejaculatory duct. Transurethral resection of the ejaculatory duct (TURED) has resulted in marked improvement in semen parameters, and pregnancies have been achieved.

Adult↗

[Acceleration of pubertal development].

Sexual precocity is defined as the appearance of physical signs of puberty at a time -3 SD before the mean age for the population, that is before 8 years for girls and 8.5-9.0 years for boys. The Authors discuss about etiology, therapeutic approach, indications for treatment, results and still open problems in this condition. From the pathogenetic point of view disorders that induce sexual precocity can be classified as gonadotropin-releasing hormone (Gn-RH) dependent or Gn-RH independent. Premature activation of the hypothalamic Gn-RH pulse generator may be induced by malformations, tumours and other neurogenic lesions of the CNS, while in more than 70% of patients the primary factor is not identifiable (idiopathic form). Idiopathic true precocious puberty is more frequent in females, whereas in males CNS lesions, especially neoplasms, are more prevalent. The main aims of therapy in precocious puberty are to inhibit puberty, to stop and possibly reverse the progression of secondary sex characteristics and particularly menses, to slow down skeletal maturation, to delay epiphyseas closure and consequently to improve final height, to preserve fertility, to improve psycho social well-being and naturally to treat the underlying cause, when known. Gonadotropin-releasing hormone agonists (Gn-RHa) are now the therapy of choice when the disease is Gn-RH dependent. They are effective both in arresting pubertal development and in improving final adult height. In selected cases with a great reduction of growth velocity an association with hGH therapy is possible. We must pay special attention to bone mineralization with this kind of treatment at this very delicate age.

Adolescent↗

THE LYON HYPOTHESIS.

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Chromosome Aberrations↗