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Use of stage of change (SOC) to develop an STD/HIV behavioral intervention: phase 1. A system to classify SOC for STD/HIV sexual risk behaviors--development and reliability in an STD clinic.

This paper reports on the initial phase in the development, program implementation, and inter-rater reliability of an application of Stage of Change (SOC) behavioral theory for use in STD/HIV risk reduction. SOC was adapted to assess readiness for sexual behavior change in an urban STD clinic in Rochester, New York. A standardized staging grid and protocol were developed and implemented as part of HIV pre- and post-test counseling. A "client instructor" methodology was used to assess standardization and staff inter-rater reliability. Percent agreement for stage assessment for target behaviors was calculated. The Rochester STD/HIV Behavioral Counseling (RoSHBeC) Staging Grid and Protocol was used to train staff and this staging system was implemented in the STD clinic. After training, staff identified the correct behavioral target and stage 90% of the time. Inter-rater agreement for SOC classification was greater than 70%. Our experience demonstrates that it is possible to develop, implement, and sustain an integrated provider-delivered STD/HIV behavioral intervention in a busy urban STD Clinic. This staging system has the potential for use in other settings and for other health-related behaviors.

Acquired Immunodeficiency Syndrome↗

Temperature-dependent sex determination in reptiles: proximate mechanisms, ultimate outcomes, and practical applications.

In many egg-laying reptiles, the incubation temperature of the egg determines the sex of the offspring, a process known as temperature-dependent sex determination (TSD). In TSD sex determination is an "all or none" process and intersexes are rarely formed. How is the external signal of temperature transduced into a genetic signal that determines gonadal sex and channels sexual development? Studies with the red-eared slider turtle have focused on the physiological, biochemical, and molecular cascades initiated by the temperature signal. Both male and female development are active processes--rather than the organized/default system characteristic of vertebrates with genotypic sex determination--that require simultaneous activation and suppression of testis- and ovary-determining cascades for normal sex determination. It appears that temperature accomplishes this end by acting on genes encoding for steroidogenic enzymes and steroid hormone receptors and modifying the endocrine microenvironment in the embryo. The temperature experienced in development also has long-term functional outcomes in addition to sex determination. Research with the leopard gecko indicates that incubation temperature as well as steroid hormones serve as organizers in shaping the adult phenotype, with temperature modulating sex hormone action in sexual differentiation. Finally, practical applications of this research have emerged for the conservation and restoration of endangered egg-laying reptiles as well as the embryonic development of reptiles as biomarkers to monitor the estrogenic effects of common environmental contaminants.

Amino Acid Sequence↗

Phosphoproteins and protein kinase activities of ventral prostate chromatin during sexual maturation in the rat.

1. In the ventral prostates of rats undergoing normal sexual development, chromatin-associated phosphokinase activities toward dephosphophosvitin and lysine-rich histones were maximal at 48 days of age, whereas phosphorylation of endogenous chromosomal proteins was greatest in the sexually mature adult. 2. Polyacrylamide gel electrophoretic analysis of chromatin proteins from these animals revealed age-dependent changes in the amount of phosphorylation of specific proteins. 3. These were most evident in highly phosphorylated H2SO4-soluble nonhistone proteins and in those nonhistones (13-16 K and 20-35 K mol. wt) which are insoluble in H2SO4.

Animals↗

Gonadal defects and hormonal alterations in transgenic mice expressing a single chain human chorionic gonadotropin-lutropin receptor complex.

To study the effects of premature and chronic ligand-mediated luteinizing hormone receptor (LHR) activation on reproductive development, we have generated transgenic mice expressing a genetically engineered, constitutively active yoked hormone-receptor complex (YHR), in which a fusion protein of human chorionic gonadotropin (hCG) is covalently linked to the N-terminus of rat LHR. YHR-expressing mice (YHR(+)) were analyzed at pre- and post-pubertal ages. Relative to wild type (WT) controls, male mice exhibited prepubertal increases in testosterone levels and seminal vesicle weights, and decreases in serum FSH, serum LH, testes weight, and the size of the seminiferous tubules. In adult male YHR(+) mice, testosterone and LH levels are not significantly different from WT controls. However, FSH levels and testes weights remain decreased. Female YHR(+) mice undergo precocious puberty with early vaginal opening, accelerated uterine development, enhanced follicular development, including the presence of corpora lutea, and an increase in serum progesterone. At 12 weeks of age, the ovary exhibits a relative increase in the amount of interstitial tissue, comprised of cells that are hypertrophic and luteinized, as well as follicles that are degenerating. Additionally, hemorrhagic cysts develop in approximately 25% of the transgenic mice. These degenerative changes are consistent with an aging ovary suggesting that CG-induced LHR activation in female mice leads to precocious sexual development and ovarian lesions. Taken together, these data indicate that the single chain YHR is functional in vivo and demonstrate that YHR(+) mice provide a novel system to further understand the reproductive consequences of aberrant LHR activation.

Age Factors↗

Plasma follicle-stimulating hormone during photoperiodically induced sexual maturation in male Japanese quail.

Follicle-stimulating hormone (FSH) was measured in Japanese quail using a heterologous radioimmunoassay, the specificty of which was confirmed by its cross-reactions with purified chicken FSH and luteinizing hormone (LH). Plasma concentrations of FSH, LH and testosterone were determined in quail during the testicular growth and sexual maturation which follows their transfer from short to long daylengths. All three hormones could be detected in short-day birds but their concentrations were greatly increased following photostimulation. Plasma FSH increased 12-fold during the first 9 long days, remained at this level for a week, and then declined steadily so that by the time the birds were sexually mature the level of FSH had decreased to one-third of the maximum level. LH reached a high level (five times the short day level) after 4 long days. Thereafter two patterns of LH secretion could be distinguished. In one experiment the high level of LH was maintained unchanged throughout sexual maturation while in another experiment LH secretion decreased significantly between days 11 and 28 of photostimulation. A strong correlation existed between testicular growth and the plasma FSH concentration. It was maximal during the phase of rapid testicular growth and decreased as spermiogenesis began. The pituitary FSH content increased during photostimulation. Castration caused a 20-fold rise in plasma FSH compared with that in intact quail. The change in LH concentration after castration was about eightfold. The changes in hormone secretion were strikingly similar to those found during sexual development and puberty in the rat.

Animals↗

[Differentiation and development of internal sexual organs, and müllerian inhibiting substance].

Internal sexual organs are differentiated and developed by androgens and regressed by müllerian inhibiting substance(anti-müllerian hormone). The role of 5 alpha-dihydrotestosterone, reduced form of testosterone by 5 alpha-reductase, in terms of development of Wolffian duct is discussed with soluble mesenchymal factor responsible for the epithelial branching morphogenesis of mouse seminal vesicle on the basis of experimental results using organ culture assay of mouse new-born seminal vesicle. An update of müllerian inhibiting substance, a fetal regressor of female internal organs such as uterus, fallopian tubes and upper third vagina, is also discussed.

Androgens↗

A reproductive option for women with Turner's syndrome.

In the past, management of congenital absence of ovaries in women with Turner's syndrome (TS) was limited to replacement of ovarian hormones to initiate pubertal development. Until recently, adoption or stepparenting were the only parenting options. However, with new developments in assisted reproduction, women with TS may be able to successfully complete pregnancy and childbearing. There are specific nursing considerations for children and adolescents to follow: anticipatory guidance regarding sexual development; encouraging discussions of the range of options that are available for women with TS regarding reproduction; and assisting these children and adolescents in understanding the benefits and limitations associated with one reproductive option, in vitro fertilization.

Adolescent↗

Review of the embryologic development of the pituitary gland and report of a case of hypophyseal duplication detected by MRI.

We describe the clinical manifestations, associated abnormalities, MRI appearances and pathologic significance of a case of hypophyseal duplication. A 16-year-old girl presented with delayed sexual development and history of midline craniofacial anomalies. MRI revealed paired infundibula extending inferiorly to two small pituitary glands, a midline hypothalamic mass, and a midline cleft in the basisphenoid. Twelve cases of pituitary duplication have previously been described. The suggested pathogenesis is duplication of the prechordal plate and anterior end of the notochord during early embryologic development.

Abnormalities, Drug-Induced↗

[Hypospadias in adulthood].

Hypospadias should not be considered as a congenital local defect only in the development of the urethra; the problem extends beyond the local malformation to the physical and intellectual development of the patient. It would also be incorrect to regard the problem of hypospadias as settled if the operative correction is performed, since mostly with puberty, but partly also later, changes may occur in general but particularly also in sexual development, placing a difficult burden on the hypospadias sufferer. The discussion of hypospadias problems in adults therefore embraces a subject that reaches far beyond operative correction into areas of miction, fertility and sexuality and therefore represents a wide complex of physical and mental problems. Above all, the question should be examined what quality of life a hypospadias patient can expect in the future after correction of this congenital malformation in infancy. The following factors describing the special circumstances of living after hypospadias operation, appear to be worthy of discussion: 1. The physical situation which includes the ability of erection, miction, fertility, the cosmetic aspect of the outer genital organ and potential consequences of combined malformations. The mental or "psychic" situation, which reaches into sexual life, partnership and profession. Only a few clinical departments concerned with the primary correction of hypospadias in infancy have controlled a group of patients up to adult age. For these reasons we considered it necessary to collect as far as possible the experiences mentioned in the literature and to combine them with our own observations to arrive at corresponding conclusions.

Abnormalities, Multiple↗

Pubertal development and onset of psychosis in childhood onset schizophrenia.

In this study, pubertal development was examined for a sample of children and adolescents with childhood onset schizophrenia (COS) defined as psychosis by age 12. Developmental and psychiatric histories were obtained for 28 adolescents (mean age 14.5 +/- 2.3 years) with severe, treatment refractory COS (14 males, 14 females). Age of onset of psychosis was also examined in relation to menarche and development of secondary sex characteristics. Girls had a trend towards developing secondary sex characteristics earlier than boys (P = 0.06), consistent with North American norms. Males (N = 14) and females (N = 14) had similar age of onset of psychosis. The age of development of secondary sex characteristics was associated with onset of psychosis for girls, but this finding was driven by one outlier. There was no significant correlation between development of psychosis and menarche. Neither male nor female probands differed significantly from their well siblings or from North American norms in their age of onset of pubertal development. There was no evidence of early onset of secondary sex characteristics for this sample. Finally, there was an absence of a clear relationship between onset of psychosis and indices of sexual development for these very early onset cases.

Adolescent↗

Object loss, aggression, and gender identity.

This paper arises from a clinical, observational, longitudinal study of aggression in normal children in the first two years of life. In this study of one of the research children the authors seek to delinate how the emergence and vicissitudes of aggression in a little boy are affected by a variety of strains in the course of his early development and how the aggression affects all the major developmental tasks in his young life. In particular, the authors attempt to follow the interdependent currents of object relations, aggression, and early sexual development.

Aggression↗

The genetic contribution to pubertal growth and development studied by longitudinal growth data on twins.

Forty-eight pairs of MZ and like-sex DZ twins of Panjabi parentage were studied longitudinally for such pubertal changes as growth of genitalia, pubic, axillary and facial hair, change of voice and ejaculation of semen in boys, and growth of pubic and axillary hair, breast development and onset of menarche in girls, besides growth in height and weight. Mean intra-pair age differences are small and intra-pair correlations for age at different secondary sexual developments are higher in MZ twins than in DZ twins in both sexes. Mean intra-pair differences and intra-pair correlations for the time taken to pass from first stage to the final stage of development also present a similar picture. Intra-pair height and weight differences and differences in their growth velocities also indicate that MZ twins are more concordant than DZ twins throughout the adolescent growth period. These findings indicate a strong genetic component in regulating the pubertal changes as well as in the growth of height and weight in the two sexes. The role of environmental factors in at least some of the pubertal changes is also indicated.

Adolescent↗

[Growth and development of children in Cuba].

During the years 1972 to 1974, a great scale study was carried out on development and growth taking at random a stratified sample of multiple stages of 50,311 children from birth to 20 years. Fifteen anthropometric dimensions were considered and evaluation was made of sexual development in both sexes. In girls, the age of menarche was registered. An X-ray of the hand was taken to 10% of the sample. One year later, 30% of the sample was X-rayed again to determine speed of growth. Response of the population was close to 94%. The importance of a national system of growth is recognized, together with the colaboration of the orgaism of masses to achieve these purposes. Information related with some of measurements reported is offered and comments related with these findings are made.

Adolescent↗

Puberty: when it comes too soon guidelines for the evaluation of sexual precocity.

Sexual precocity, evidence of secondary sexual characteristics before the age of 9 years in boys and 8 years in girls, can be distressing for families and challenging for primary care physicians. In this article, I discuss the most common causes of early sexual development and provide an algorithm for the initial evaluation of such children. The information presented here is not intended to be a complete guide to the diagnosis of disorders resulting in sexual precocity, but rather is designed to aid in the initial evaluation and facilitate the identification of those children who would benefit from referral to a pediatric endocrinologist.

Child↗

Sexual dimorphism of the developing human brain.

1. Sexual dimorphism of human brain anatomy has not been well-studied between 4 and 18 years of age, a time of emerging sex differences in behavior and the sexually specific hormonal changes of adrenarche (the predominantly androgenic augmentation of adrenal cortex function occurring at approximately age 8) and puberty. 2. To assess sex differences in brain structures during this developmental period volumes of the cerebrum, lateral ventricles, caudate, putamen, globus pallidus temporal lobe, amygdala, and hippocampus, and midsagittal area measurements of the corpus callosum were quantified from brain magnetic resonance images of 121 healthy children and adolescent and examined in relation to age and sex. 3. Males had a 9% larger cerebral volume. When adjusted for cerebral volume by ANCOVA only the basal ganglia demonstrated sex differences in mean volume with the caudate being relatively larger in females and the globus pallidus being relatively larger in males. The lateral ventricles demonstrated a prominent sex difference in brain maturation with robust increases in size in males only. A piecewise-linear model revealed a significant change in the linear regression slope of lateral ventricular volume in males after age 11 that was not shared by females at that or other ages. 4. Amygdala and hippocampal volume increased for both sexes but with the amygdala increasing significantly more in males than females and hippocampal volume increasing more in females. 5. These sexually dimorphic patterns of brain development may be related to the observed sex differences in age of onset, prevalence, and symptomatology seen in nearly all neuropsychiatric disorders of childhood.

Adolescent↗

Exposure of juvenile guppies to three antiandrogens causes demasculinization and a reduced sperm count in adult males.

It has been thoroughly established that the fungicide vinclozolin and the persistent DDT metabolite p,p'-DDE, can function as antiandrogens in mammals in a manner similar to the therapeutic antiandrogen flutamide. In mammals, these chemicals bind the androgen receptor and prevent the transcription of the associated genes causing abnormal sexual development and demasculinization. There are few similar studies in fish and so far it has not been demonstrated that these chemicals have any antiandrogenic effects in this group. In the present study, juvenile guppies (Poecilia reticulata) were fed sublethal doses of vinclozolin, p,p'-DDE or flutamide from birth to adulthood. At sexual maturity, we measured a suite of male sexual characteristics that are known to be under androgen control. All three chemicals caused a reduction in the orange display coloration, inhibited gonopodium development, reduced the sperm count and suppressed courtship behaviour, in a manner consistent with antiandrogen action. Only the gonodosomatic index was unaffected by the treatments. In addition, the three chemicals skewed the sex ratio at adulthood and caused delayed maturation. The altered characters are all considered to be important for male mating success and their impairment indicates that antiandrogens may seriously compromise male reproductive fitness.

Androgen Antagonists↗

Steroids after birth-puberty.

The production of gonadal steroids in the perinatal period may have an important influence on the later development of the hypothalamo-pituitary-gonadal axis. In the prepubertal period there is an increased output of gonadal steroids and of androgens from the adrenal cortex, with a further increase as the secondary sex characters develop. The precise role of individual steroids in the maturation of the reproductive system and of the neuroendocrine regulating mechanisms will probably remain unclear unless conclusions are based on longitudinal studies in which hormone production is related precisely to different parameters of sexual development and somatic growth.

Adolescent↗

Long-term effects of accelerated or delayed sexual maturation on reproductive output in wild female house mice (Mus musculus).

The effects of acceleration and delay of puberty in female house mice on survival and reproduction were tested using 6 experimental groups: (1) control females mated at the time of first oestrus, (2) females mated at weaning, (3) females treated with male urine starting at weaning and mated at first oestrus, (4) females housed in groups and mated at first oestrus, (5) females housed alone, treated with urine from grouped females and mated at first oestrus, and (6) females housed alone and mated at 68 days of age. Females caged with males at weaning or treated with male urine and mated at puberty had lower rates of survival to 180 days of age, but did not differ in rates of fertility from mice in the other four treatments. Those females that were housed with males from weaning or treated with male urine also had smaller total numbers of litters, fewer total young, and smaller average litter sizes than did females for which the age of mating was delayed, by grouping or treatment with urine from grouped females, or by being held until age 68 days before mating. Control females mated at first oestrus generally were intermediate or did not differ from the male treatments on these dependent variables. There were no differences in the average number of female young/litter across the 6 treatments. However, females that were delayed in age of first mating had significantly more male young/litter than did females that were accelerated in their sexual development or control females.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗