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Effect of androgen on growth hormone secretion and growth in boys with short stature.

The response of plasma growth hormone (GH) to insulin-induced hypoglycaemia (IIH) and arginine infusion (AI) was studied in 22 young males (ages 8 to 17 years) with short atature and absent or delayed sexual maturation, before and after androgen administration. During initial evaluation, 5 patients had blunted GH response to IIH, 12 responded subnormally to AI and 4 failed to respond normally to either stimulus. These same studies were repeated in each patient following androgen administration. The source of androgen was as follows: a) 5 days of testosterone propionate (25 mg intramuscularly daily) in 20 patients. b) Methyltestosterone, 10 mg t.i.d. orally for four days in the other 2 subjects. In almost every case, androgen administration resulted in raising the levels of fasting GH and enhancement of the GH responses to IIH and AI was observed. Patients manifesting subnormal GH responses to these stimuli before androgen consistently demonstrated a normal response when challenged with identical stimuli during androgen administration. Growth velocities during the year following these studies were significantly increased in most instances and the growth spurts correlated well with the progression of sexual maturation. Sustained improvement in the GH responses to IIH and AI were uniformly observed in 3 patients when repetitive studies were performed 8 to 12 months later during spontaneous advancing sexual development. The results indicate that brief androgen administration can be helpful in delineating the cause of growth retardation in boys with short stature and delayed sexual maturation, particularly when the diagnosis of isolated growth hormone deficiency is suspected. They also offer prognostic value in determining growth potential in this same group of young males.

Administration, Oral↗

Male reproduction and environmental and occupational exposures: a review of epidemiologic methods.

Concerns that chemical exposures in the environment have been detrimental to male sexual development and fertility have been heightened by reports of declining sperm counts over the past 50 years. Marked geographic variation has been found in semen quality and in the incidence of testicular cancer and certain urogenital defects. Debate continues over the existence, magnitude and significance of these trends, and how best to evaluate the hypothesis that in utero and childhood exposures to estrogenic compounds may be to blame. Epidemiologic methods for assessing the impact of hazardous substances on male reproductive health have been developed mainly in the area of occupational medicine, and this paper will review the currently recommended methods. These include questionnaires to determine reproductive history and sexual function; reproductive hormone profiles; and semen analyses such as sperm concentration, motility, and morphology. New research tools that show significant promise from the fields of clinical reproductive medicine and reproductive toxicology are discussed as possible additions to epidemiologic studies, including assays of sperm function and genetic integrity, and biomarkers of DNA damage. For population-based studies involving occupational groups or communities with environmental exposures, issues related to the cost, validity, precision and utility of these methods must be carefully considered.

Environmental Exposure↗

Problems with sexuality after sexual assault.

In this article, we review a number of studies on sexual functioning after sexual assault. Among the studies discussed, three different approaches can be distinguished: the descriptive analyses of sexual functioning and sexual problems, the exploration of factors which predict sexual problems, and the study of relationships between sexual problems and other psychological problems. Although the studies vary considerably in methodology, they point to the conclusion that frequency of sexual contact decreases after sexual assault. Satisfaction and pleasure in sexual activities seem to diminish for a considerable group of victims for at least 1 year postassault. In several studies it was revealed that victims develop sexual problems that can persist for years after the assault. These include response inhibiting problems, such as fear and arousal and desire dysfunctions. Most researchers have found that factors such as a young age, a known offender, and penetration during the assault are related to sexual problems. With respect to physical violence used during the assault, the results are inconclusive. Furthermore, emotions felt during and immediately after the assault, such as anger towards self, shame, and guilt, may predict sexual problems. Avoidance of sexual contact also appears to be related to sexual problems. A loving and understanding partner seems to be a protective factor. Finally it can be concluded that sexual problems are related to other psychological problems, including posttraumatic stress symptoms and depression.

Female↗

Experiences against HIV/AIDS/STDS of Somalis in exile in Gothenburg, Sweden.

Since 1989, the City of Göteborg Immigrant Services Administration has been making efforts to inform about HIV/AIDS. The purpose has been to ensure that even immigrant residents of the City of Göteborg (Gothenburg) have access to relevant information about HIV/AIDS. The administration's efforts have been a part of the collected efforts of Gothenburg to prevent the spreading of HIV. This paper attempts to discover and describe experiences against HIV/AIDS/STDs of Somalis in Exile in Gothenburg, Sweden. A qualitative sociological in-depth interviews with 13 individuals (6 women and 7 men) and with semi-structured and themetized emerging design was carried on. A follow up focus group interviews with 10 individuals (2 women and 8 men) was also performed. The paper reveals that the general understanding of subjects on the issues under discussion is almost the same though details may vary from one research participant to the other. They have described this through narratives. STDs and specially HIV/AIDS was perceived as something dishonourable by the subjects. The HIV/AIDS is perceived as a sin which Allah sends to punish those who have fornication or sex without marriage (Zinna). Of course, this tendency of shying off the problem leads to ignorance of how to behave, which in turn decreases the risk of perceptions and as a result may also increase the risk of being infected. As concerns protection as a preventive measure, attitudes vary. The traditionalists have argued that condom increased the possibility of promiscuity or fonication, while young and more modern people saw condom as something good. We may conclude that Somalis who have arrived in Western world and in Sweden as adults did never have a modern sexual education for themselves due to socio-cultural reasons and this has important implication for giving proper information to their children about sex organs, human sexual development and preventive measures against HIV/AIDS/STDs. These immigrant parents should be offered culturally sensitive communication and educational programmes aimed at raising their awareness about teenagers sexuality and the preventive measures against HIV/AIDS/STDs.

Acquired Immunodeficiency Syndrome↗

[Turner's phenotype and diagnosis of Noonan's syndrome].

The Authors describe two cases of Noonan's Syndrome (Turner phenotype and normal Karyotype), underlining the necessity of a differential diagnosis with the "True" Syndrome of Turner, for the presence, in the latter, of a non development of the height, weight and phenotype, which moves away from the standard much. While on the contrary in the Noonan's syndrome both the sexual development and the evolution of the height and weight may be normal and in the latter syndrome, so, the attention of the Doctors has to be turned prevalently to the congenital cardiopathy (almost always stenosis of the pulmonary artery), which can also impair the life of the patient.

Adolescent↗

[Continuing studies on the stability of sex steroids in the feces of cows over 12 weeks].

In recent years an increasing number of reports were published indicating disturbances in the reproduction and sexual development in human beings and animals. These findings are seen in correlation with the increasing contamination of the environment with xenoestrogens. The importance of natural sexual steroids as a cause for this situation was poorly taken into account in the past. Therefore it was aimed by the study presented to contribute to knowledge in these questions. Samples of faeces were collected from 18 non pregnant and pregnant cows and their contents of estrogens and progesterone were analysed over a 12 weeks period as equivalent values of the standard substances estrone (E1) respectively 4-pregnene-20 beta-ol-3-one (20 beta P4) by using an enzyme immunoassay. The values of the substances of concern are decreasing gradually during the period of time examined. The median of the E1-equivalent dropped below the starting value in the ninth week, but the 20 beta P4-equivalent reached this level just in the second week. After the 12 weeks of observation under ambient temperature of 20 to 23 degrees C the examined equivalents of E1 and 20 beta P4 showed about 20% respectively 8% of the values measured at the beginning of the study.

Animals↗

Idiopathic male pseudohermaphroditism: variations in presentation and management.

UNLABELLED: Male pseudohermaphroditism (MPH) is the abnormal development of genitalia in an individual with a 46,XY chromosome complement and testicular tissue. The etiology of MPH is unknown in most cases, which are defined as idiopathic. OBJECTIVE: To analyze the data for cases of idiopathic MPH. PATIENTS AND METHODS: A retrospective study of 29 patients with idiopathic MPH and no uterus. RESULTS: Four patients had a family history of abnormal sexual development and five had low birth weight. The initial manifestations were sexual ambiguity (26), microphallus and hypospadias (2), and primary amenorrhea (1). Basal and/or stimulated testosterone concentrations showed insufficient testosterone secretion in three patients. Genitography showed a vagina in 13 patients. Male genitoplasties were performed on 21 out of the 24 patients reared as males and female genitoplasties on five patients. Histological studies of the gonads of these showed streak gonads in one, normal gonads in one and signs of testicular dysgenesis in three others. Molecular studies on the SRY gene (17) showed no mutation. CONCLUSIONS: Idiopathic male pseudohermaphroditism is a heterogeneous condition, even within families with a history of this condition. We propose a set of guidelines for the management of these patients.

Adolescent↗

Elevated luteinizing hormone in prepubertal transgenic mice causes hyperandrogenemia, precocious puberty, and substantial ovarian pathology.

In women, chronically elevated androgens have been associated with polycystic ovarian syndrome and infertility. Recently, we described transgenic mice with elevated serum LH secondary to targeted expression of a transgene encoding a chimeric LH beta-subunit. Mature transgenic females exhibit elevated androgens, anovulation, and a range of ovarian phenotypes including cysts, widespread luteinization, and tumors. In the present study we have examined serum levels of LH and testosterone and the concurrent development of the reproductive system in prepubertal mice. Serum LH in prepubertal females was elevated despite increased serum testosterone and estradiol, indicating a relative insensitivity to steroid negative feedback. Elevated serum LH and hyperandrogenemia resulted in accelerated vaginal opening and ovarian follicular development in transgenic females. Precocious antral follicle formation and conspicuous hypertrophy of the theca-interstitium preceded the development of large cysts with marked hemorrhage. Based on these studies we conclude that chronic prepubertal elevation of serum LH results in gonadotropin-dependent hyperandrogenemia, leading to abnormal sexual development and significant ovarian pathology.

Aging↗

Acceleration of sexual maturation in female rats by male stimulation.

In comparison to controls reared in isolation, female rats reared in the presence of an adult male from weaning attained puberty 5 days earlier when living in groups or almost 9 days earlier when living singly with a male. Accelerated sexual development occurred in the absence of accelerated physical growth.

Animal Communication↗

Sexually abused and nonabused mothers' discussions about sex and their children's sexual knowledge.

This study investigated the impact of a mother's experience of childhood sexual abuse on her discussion of sex with her child. Two groups of sexually abused and nonabused mothers, drawn from a larger community sample and matched for social class and the sex and age of their index children, were asked about discussion of sexual information within their family. Children were interviewed about their sexual knowledge. Significantly more mothers who reported an incident of sexual abuse during their childhood said that they had detailed discussions with their child about sexual development and contraception than mothers who reported no childhood incidence of abuse. Although there was no difference between the two groups in independent interviewers' ratings of the children's overall sexual knowledge, more children from the abused mothers' group mentioned their parents as a definite source of sexual information, in particular, regarding contraception. There were also differences between the two groups in the children's responses to a set of ambiguous pictures. More children in the abused mothers' group than the nonabused group gave stories related to child abductions and the possibility of sexual abuse in response to two of the pictures. A mothers' willingness to acknowledge childhood sexual abuse is related to more open discussion of sexual information within the family.

Adolescent↗

Fertility awareness as a component of sexuality education. Preliminary research findings with adolescents.

Fertility awareness refers to the observation and interpretation of cervical mucus, often called vaginal discharge. A woman's cervical-mucus pattern indicates the time of ovulation and differentiates the fertile and infertile phases of the menstrual cycle from each other. Fertility awareness enables a woman to know when pregnancy can and cannot occur on a daily basis during each menstrual cycle. There has been, to date, almost no exploration of the appropriateness of fertility-awareness instruction for adolescents. A review of the literature on adolescent cognitive development, sexual activity, knowledge of fertility and contraceptive risk-taking behavior is presented. Based on the literature review, a theoretical rationale for fertility-awareness instruction as a unique sex-education curriculum for adolescents is proposed. The content and teaching techniques of a fertility-awareness presentation for teenagers is described. Directions for future research in fertility-awareness instruction for teenagers, and the need for long-term follow-up to assess the effects of such education on teenagers' sexual activity and contraceptive use are discussed.

Adolescent↗

Posterior hypospadias: long-term followup after reconstructive surgery in the male direction.

Posterior hypospadias with a scrotal or perineal meatus results from a defect in step 3 of male sexual differentiation. The different etiological factors underlying this condition result in a broad spectrum of presentations ranging from the isolated form to complex ambiguity of the external genitalia, such as male pseudohermaphroditism. Between 1952 and 1988 a total of 92 patients with posterior hypospadias underwent a 2-stage reconstruction at our department. A retrospective study was performed with the aim of evaluating the long-term results in these patients. Our special interest focused on the functional and cosmetic results, exocrine and endocrine functions, as well as the sexual lives of the patients. While satisfactory results were obtained in two-thirds of the 42 male patients available for long-term followup, there were 13 patients who at followup still presented with complex sexual ambiguity. In 6 of these patients androgen receptor defects were detected by means of biochemical as well as molecular-biological investigations. Our data emphasize the importance of androgen metabolism for male sexual development and underline the necessity of careful evaluation in these children.

Adolescent↗

Mass media influences on sexuality.

The mainstream mass media (television, magazines, movies, music, and the Internet) provide increasingly frequent portrayals of sexuality. We still know relatively little about how this content is used and how it affects sexual beliefs and behaviors. The few available studies suggest that the media do have an impact because the media keep sexual behavior on public and personal agendas, media portrayals reinforce a relatively consistent set of sexual and relationship norms, and the media rarely depict sexually responsible models. More longitudinal research, especially with early adolescents is needed to learn more about how media content is attended to, interpreted, and incorporated into developing sexual lives.

Adolescent↗

Age-related effects of transection of the testicular blood vessels on subsequent testicular development in the pig.

Pigs of different ages were studied to assess the effect of age on the development of the testes after intra-abdominal transection of the testicular artery and vein. Transection of the testicular artery and vein at different stages of sexual development had a variable effect on the growth and differentiation of the testes. Transection performed at a young age (2 months) had no effect on the development of the testes (previous study). The animals used in this study were between 3 and 12 months (adult) at the time of surgical intervention. Their testes appeared to be more sensitive to disturbance of the main blood supply. The alternative vascular pedicle (vasal artery) was unable to adapt sufficiently to the increased physiological requirements of the testis during development in more than 50% of the animals. The results obtained from adult males indicate that intra-abdominal transection of the testicular vessels invariably has a deleterious effect on the testis.

Age Factors↗

[The effect of the actoprotector preparation bromantane on the postnatal development of rat pups].

The purpose of this work was study of the late-term results of a course of the actoprotector bromantan on the formation and development of the rat progeny. Bromantan was given per os daily in doses of 30, 150, and 600 mg/kg once a day: females received the drug for 15 days (2.5 estrous cycles), males for 60 days (whole cycle of spermatogenesis). When the course of treatment with the drug ended, the females were put together with the males for two weeks. The experiments were subdivided into two series: in series I the progeny obtained from coupling of experimental males with intact females was studied, in series II the progeny of intact males and experimental females. According to the results of the investigation, bromantan produced a late-term effect on the formation and development of the offsprings. The number of females who gave birth in series I and II of the experiment, despite a low dose-dependent increase, did not differ significantly from the controls. In series I of the experiment the litter increased insignificantly depending on the dose (by 0.3, 14.9, and 23.4%, respectively). In distinction, in the case of experimental females given 30 and 600 mg/kg bromantan before copulation (series II) the number of young rats in the litter insignificantly reduced (by 34.9 and 44.2%), in the case of rats given 150 mg/kg bromantan the litter increased (by 45%, p < 0.05). Both in series I and series II the mean weight of the newborns in the first week was significantly higher than the weight of the controls. After that the growth in body weight was insignificantly slower. Evaluation of the functional condition of the nervous system and terms of physical development of the progeny in series I and II of copulation showed an insignificant increase in the rate of maturation of the sensorimotor reflexes and physical parameters of the young experimental rats. The "open-field" test conducted on the 40th day of life showed increase of motor (by 8.0-21.6%) and exploration activity (by 94.5-109.9%, p < 0.05) in the young experimental rats of series I and, at the same time, decrease of the grooming parameters (by 26.9-63.5%, p < 0.05) and emotionality. In all experimental groups of series II horizontal and vertical motor and searching activity was reduced. The authors believe that the actoprotector bromantan, possessing a dopaminergic effect in the mechanism of its action, may cause a late-term influence on prolactin secretion in lactating rats. The deficiency in this hormone in the early period of postnatal development affects the neurochemical organization of the hypothalamo-hypophyseal region and the brain areas connected with it, involving in this case also the mechanisms of sexual differentiation of the brain and, as a consequence, the somatic and sexual development of the progeny.

Amantadine↗

[Effect of prenatal hyperandrogenism during pregnancy and on postnatal development of rats].

Hyperandrogenia was modelled in the female rats within the whole term of pregnancy by means of testosterone or dihydrotestosterone. Both androgens have been established to induce significant prenatal mortality and high percentage of mortinatus and postnatal mortality of progeny. Hyperandrogenization influenced negatively the sexual development and reproductive function of the female progeny versus the male one.

Androgens↗

Amphibians as a model to study endocrine disruptors: II. Estrogenic activity of environmental chemicals in vitro and in vivo.

Several environmental chemicals are known to have estrogenic activity by interacting with development and functions of endocrine systems in nearly all classes of vertebrates. In order to get a better insight of potential estrogenic effects on amphibians caused by environmental pollution this study aims to develop a model for investigating endocrine disruptors using the amphibian Xenopus laevis. In that model the potential estrogenic activity of endocrine disruptors is determined at several levels of investigation: (I) binding to liver estrogen receptor; (II) estrogenicity in vitro by inducing vitellogenin synthesis in primary cultured hepatocytes; and (III) in vivo effects on sexual development. Here we deal with establishing methods to assay estrogenic activity of environmental chemicals in vitro and in vivo. In vitro we used a semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) technique to determine mRNA-induction of the estrogenic biomarker vitellogenin in primary cultured hepatocytes of male Xenopus laevis. Time courses of vitellogenin-mRNA in the presence and absence of 10(-6) M 17 beta-estradiol (E2) resulted in a marked loss of mRNA from controls after 2 days while E2 treatment kept vitellogenin-mRNA at a relatively stable level. After 36 h of incubation estrogenic activities of E2, 4-nonylphenol (NP), and 2,2-bis-(4-hydroxyphenyl)-propan (bisphenol A) at concentrations ranging from 10(-10) to 10(-5) M were assayed by RT-PCR of vitellogenin-mRNA and showed the following ranking of dose-dependent potency: E2 > NP > bisphenol A. These in vitro results were confirmed further by in vivo experiments determining sexual differentiation of Xenopus laevis after exposure to E2 and environmental chemicals during larval development. Concentrations of 10(-7) and 10(-8) M E2 as well as 10(-7) M of NP or bisphenol A caused a significant higher number of female phenotypes compared to controls indicating a similar ranking of estrogenic potencies in vivo as in vitro. In addition, butylhydroxyanisol and octylphenol, both showed feminization at 10(-7) M while octylphenol was also effective at 10(-8) M. In summary these results demonstrate for the first time the use of a semiquantitative RT-PCR technique for screening estrogenicity by assaying mRNA induction of the estrogenic biomarker vitellogenin in vitro. The combination of this newly developed method with classical exposure experiments is necessary for determination of the biological significance of estrogenic chemicals.

Animals↗

Effect of strain, feed allocation program, and age at photostimulation on reproductive development and carcass characteristics of broiler breeder hens.

A study was conducted with broiler breeder pullets to investigate the effects of strain, age at photostimulation (PS), and release from feed restriction at PS on age, BW, ovarian morphology, and carcass characteristics at sexual maturity (point of initiation of lay). Sixty birds of each of 4 strains were used. The 4 types represented a classic strain (A), 2 high-yield strains (B, C), and a roaster strain (D). Photostimulation (8L:16D to 14L:10D) was applied at 2 different ages (21 and 24 wk) to 30 birds of each strain type. Within each of the PS periods, 15 birds of each strain were fed ad libitum (F), and the remaining 15 were feed-restricted (R) following a common feeding schedule. On the day that each bird had its first oviposition, its feed was withdrawn. It was euthanized the following morning by cervical dislocation and organs were collected. Of the 3 main effects, feeding program had the greatest effect on all the parameters measured. Within the 21-wk PS treatment group, R birds reached onset of sexual maturity later than F birds (50.2+/-1.64 vs. 36.6+/-1.01 d, respectively). There were no differences in the age at sexual maturity between R and F birds for the 24-wk PS treatment (28.9+/-0.95 vs. 26.9+/-0.85 for R and F, respectively). These results suggest that by 24 wk, all strains had reached a threshold BW and responded uniformly to PS regardless of feeding program. Feed restriction reduced the number of large yellow follicles (LYF) (diameter >10 mm) (8.43+/-0.23 vs. 9.65+/-0.33 for R and F birds, respectively). Follicle number was not different between birds photostimulated at 21 or 24 wk (9.6+/-0.33 vs. 8.45+/-0.23, respectively). Feed restriction affects sexual development that can be modulated by the PS program.

Age Factors↗