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PubMed1995

[Precocious puberty and polycystic ovarian syndrome: apropos of 13 cases].

BACKGROUND: Precocious puberty and polycystic ovarian syndrome are two different entities which appear at different stages of ovarian development. Their association is uncommon. POPULATION: Thirteen girls presented idiopathic central precocious puberty with sexual development before the age of 8 years; menstruations were seen at the age of 9.5 years in one patient. Nine of them were given medroxyprogesterone or cyproterone acetate and two patients LHRH analog. Menarche occurred at a mean age of 11.8 +/- 1.5 years. After a mean free interval of 22 months, these thirteen patients developed hirsutism with irregular menstruations (eight patients) and weight gain (seven patients). The diagnosis of polycystic ovarian syndrome was confirmed by increased plasma testosterone (mean 91.1 +/- 14 ng/dl) and LH levels during LHRH test and by ultrasonography or coelioscopy. The treatment included cyproterone acetate plus 17 beta oestradiol; it was discontinued in eleven cases after 2 years of treatment. Plasma testosterone levels were normal 6 months later in association with regular menstruations. But three patients presented clinical and hormonal recurrence one year later, requiring repeated treatment. CONCLUSION: This association seems to be related to the same gonadotropin dysfunction. It is necessary to regularly follow patients treated for precocious puberty.

Androgen Antagonists↗

PubMed1998

Monthly measures of salivary testosterone predict sexual activity in adolescent males.

Strong relationships between one-time serum testosterone (T) measures and sexual activity have been demonstrated in cross-sectional analyses of adolescent males. However, a subsequent longitudinal study of a separate adolescent sample, using semiannual plasma measures, failed to replicate cross-sectional findings. The present study reexamined the relationship between T and sexual activity using more frequently collected measures of salivary T and behavior. Saliva samples and weekly behavior checklists were collected over a 2-year period from the same panel sample of males on which semiannual analyses were based. Saliva samples representing measures approximately every fourth week of study participation were selected for T assay. The association between these monthly salivary T measures and weekly reports of incidents of sexual activity was assessed with repeated measures analyses. Higher levels of salivary T were significantly associated with an increasing hazard of coital initiation, and with more frequent coital and noncoital activity. Within-individual change analyses demonstrated that increases in salivary T were associated with increased sexual activity. Comparisons of models that varied specimen type, schedule of T measurement, and type of behavioral report indicated that all three factors contribute to the varying magnitude of hormone/behavior relationships that are demonstrated. These findings are consistent with a biosocial model of adolescent sexual development that pubertal changes in T are a causal factor in the timing of sexual initiation and the frequency of activity during adolescence.

Adolescent↗

PubMed2005

[Men and women--aspects of sexological counseling in the aging].

In our times, sexuality has become an essential part of life for aging people. For the aging, psychosocial and biological changes, as well as increasing morbidity present challenges to a satisfying sexual life. Hence, the demand grows for health-care providers with basic sexological knowledge and counseling abilities. This article discusses relationships between frequent sexual difficulties and aging related organic processes. A therapeutic concept, the "Sexocorporal Approach", is introduced. This approach is based on a model of ongoing sexual development throughout the lifetime enabling adaptation to new life phases and limiting circumstances through sexual learning processes. Aside from pharmacological treatment, the encouragement of sexual learning presents an effective therapeutic approach for practitioners that can be easily learned and applied.

Age Factors↗

PubMed2003

The effects of glucose concentration on the reciprocal regulation of rRNA promoters in Plasmodium falciparum.

The developmental progression of Plasmodium falciparum is remarkably sensitive to glucose concentration. We have investigated the effects of glucose concentration on the parasite development cycle as reflected by changes of ribosomal RNA (rRNA) transcription. We showed that glucose starvation differentially affects transcriptional control of the rRNA genes by sharply repressing transcription from those loci involved with asexual development of the parasite while up-regulating transcription at those loci involved with sexual development of the parasite. Temperature change also effects regulation of transcription. We found that the effects of temperature and glucose were synergistic. We identified and compared the upstream region of the transcription start sites of each gene. These putative promoter structures are considerably different from one another and contain structures remarkably similar to rRNA control elements in other organisms.

Animals↗

PubMed2000

Promotion of safer sexual behaviour and HIV/STD prevention among adolescent students and army recruits.

Estonia is a country with a low incidence rate of HIV infection, but a high rate of STDs. Drug use is increasing among young people, with an unknown number of users. A considerable number of IVDUs are infected with hepatitis B and C viruses. There are conditions for rapid spread of HIV infection in Estonia. From 1997 to 1999, three prevention projects were carried out with young people by the Estonian Association Anti-AIDS. The idea of preventive strategies was to promote the young people's own decision making about risk behaviour. Interactive learning methods were designed for work with young people. Teachers and peer educators were seen as collaborators in prevention: for them an innovative methodological manual was issued and they were also provided with training sessions. During interactive workshops the project staff learnt from young people background issues such as aspects of their psychosocial and sexual development. From our experience, prevention must be carried out among the young people continuously as they need the development of the motivation and personal insight to establish the goals of personal (and sexual) health.

Adolescent↗

PubMed1997

Isoforms of gp138, a cell-fusion related protein in Dictyostelium discoideum.

Sexual development of Dictyostelium discoideum is a unique and useful system for the study of sexual phenomena. We have been studying molecular mechanisms of sexual cell fusion in D. discoideum and have identified several relevant cell-surface proteins. One of the proteins, gp138, was identified as a target molecule for fusion-blocking antibodies, and two genes for gp138, GP138A and GP138B, were cloned. The participation of gp138 in the sexual cell fusion was confirmed by antisense RNA mutagenesis, but it is unclear which of the genes encodes gp138. Moreover, the presence of a third gene for gp138 was indicated by gene disruption. In the present study, we generated strains of D. discoideum overexpressing either GP138A or GP138B to investigate the products of these genes. The transformants overexpressing GP138A and GP138B overproduced glycoproteins with molecular masses of 135 and 130 kDa, respectively. Although their molecular masses were different from that of gp138, the results of peptide mapping and amino acid sequencing showed that they are related to proteins, suggesting that the proteins encoded by GP138A and GP138B are isoforms of gp138 protein.

Amino Acid Sequence↗

PubMed1986

Influence of valproic acid on the gonadotropin-releasing hormone test in puberty.

Twelve epileptic adolescents on valproate (VPA) treatment were studied by means of clinical observation and gonadotropin-releasing hormone stimulation (GnRH) tests. Five patients were investigated before and during VPA treatment. Before treatment the basal and peak levels of gonadotropins were appropriate for age; during treatment both levels were depressed and the areas under the curves were significantly decreased. The long-term effect of VPA was studied in an additional seven patients. The basal levels of gonadotropins were as low and their response to GnRH as poor as in the second test of the first five patients--i.e., during VPA treatment. No recovery was noted in two patients after dose reduction or in a further two patients 10 months after the discontinuation of VPA treatment. In all the patients, however, the usual clinical signs of pubertal development and maturity were unaffected by VPA treatment. The significance of the results for sexual development and fertility is therefore uncertain.

Adolescent↗

PubMed2004

Effects of mosquito genes on Plasmodium development.

Malaria parasites must complete a complex developmental cycle in an Anopheles mosquito vector before transmission to a vertebrate host. Sexual development of the parasite in the midgut is initiated in the lumen immediately after the mosquito ingests infected blood, and the resulting ookinetes must traverse the surrounding epithelial layer before transforming into oocysts. The innate immune system of the mosquito is activated during midgut invasion, but to date, no evidence has been published identifying mosquito immune genes that affect parasite development. Here, we show by gene silencing that an Anopheles gambiae leucine rich-repeat protein acts as an antagonist and two C-type lectines act as protective agonists on the development of Plasmodium ookinetes to oocysts.

Animals↗

PubMed1995

Between Marxism and psychoanalysis: antifascism and antihomosexuality in the Frankfurt School.

In their efforts to utilize individualist psychoanalysis as a tool for understanding mass behavior, the social theorists associated with the Frankfurt School increasingly came to rely on a static, essentializing construction of sexuality which ultimately led to an equation of fascism and homosexuality. Heretofore unexamined in studies of the Frankfurt School, this equation will here serve as the starting point for a fundamental critique of the concept of sexuality developed by this influential circle of Marxist thinkers. While directed at the concept of sexuality, such a critique more importantly opens up the underlying understanding of the social and psychological realms advanced by Critical Theory. Attending to the equation of homosexuality and fascism as the central point of concern, this essay will first trace the introduction of psychoanalysis into Critical Theory through Erich Fromm and then investigate the extent of Fromm's influence on the concept of sexuality propounded by his colleagues, especially Max Horkheimer and Theodor W. Adorno. Finally, it will take up a frequently overlooked essay by Herbert Marcuse which promoted a vision of sexuality radically different from that of his associates.

Communism↗

PubMed1978

Suprahypophyseal dysfunction in a patient with asexual ateleiosis.

The neuroendocrine function of a 19 years old female dwarf with primary amenorrhoea and lack of sexual development (asexual ateleiosis) was studied. Undetectable fasting plasma levels of growth hormone (GH) and a lack of response to three different provocative stimuli was observed. Oestrogen administratin did not modify the GH response. Thyroid and adrenal function were within normal limits. Undetectable plasma levels of immunoreactive oestradiol and lack of oestrogenic activity in vaginal smears indicated absence of ovarian function. Low levels of circulating gonadotrophins with a significant rise after synthetic LH-RH administration was demonstrated, while clomiphene citrate failed to induce ovulation. Following 6 months of continuous GH administration a significant increase in the growth rate was evident, whereas no pubertal development was observed. These data are interpreted as demonstrating the suprahypophyseal origin of the sexual infantilism in a patient with inappropriate GH secretion. It is suggested that a combined deficiency of LH-RH and GH-RH may account for the aetiology of this disorder.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Endocrine disruption caused by two common pollutants at "acceptable" concentrations.

This report focuses on the impact of low concentrations of two purported endocrine-disrupting xenobiotic compounds, nonylphenol and methoxychlor, on two freshwater teleosts of the genus Xiphophorus, X. maculatus, commonly known as the platyfish, and X. helleri, commonly known as the swordtail. Nonylphenol exposure increased mortality rates, elicited stress behaviors, decreased body weight and significantly hampered gonadal development and reproductive function. Methoxychlor exposure elicited stress behaviors, decreased body weight and significantly retarded sexual development. This report demonstrates that, even at "acceptable" concentrations, these compounds pose a serious threat to our aquatic ecosystems.

Animals↗

PubMed2000

Sexually dimorphic expression of protease nexin-1 and vanin-1 in the developing mouse gonad prior to overt differentiation suggests a role in mammalian sexual development.

The mammalian sex-determining pathway is controlled by the presence or absence of SRY expression in the embryonic gonad. Expression of SRY in males is believed to initiate a pathway of gene expression resulting in testis development. In the absence of SRY, ovary development ensues. Several genes have now been placed in this pathway but our understanding of it is far from complete and several functional classes of protein appear to be absent. Sex-determining genes frequently exhibit sexually dimorphic patterns of expression in the developing gonad both before and after overt differentiation of the testis or ovary. In order to identify additional sex-determining or gonadal differentiation genes we have examined gene expression in the developing gonads of the mouse using cDNA microarrays constructed from a normalized urogenital ridge library. We screened for genes exhibiting sexually dimorphic patterns of expression in the gonad at 12.5 and 13.5 days post-coitum, after overt gonad differentiation, by comparing complex cDNA probes derived from male and female gonadal tissue at these stages on micro-arrays. Using in situ hybridization analysis we show here that two genes identified by this screen, protease nexin-1 (Pn-1) and vanin-1 (Vnn1), exhibit male-specific expression prior to overt gonadal differentiation and are detected in the somatic portion of the developing gonad, suggesting a possible direct link to the testis-determining pathway for both genes.

Amidohydrolases↗

PubMed1997

Effect of gonadotrophin and sex steroid on the scotoresponses of day old chicks of Japanese quail, Coturnix coturnix japonica.

Luteinizing hormone (LH) and testosterone propionate (TP) were tested for their effects on the development of scotorefractoriness in Japanese quail. Day old chicks of both the sexes were divided into four groups and treated with normal saline, LH (1 microg/100 g body weight) and two doses of TP (100 microg/100 g body weight- TP1 and 1 mg/100 gm body weight- TP2) over a periods of 14 weeks. In the male chicks, compared to control, LH treatment advanced and low dose of TP suppressed the development of scotorefractoriness, while high dose of TP inhibited it completely and maintained the birds in scotosensitive state. On the other hand, in females, LH treatment increased the rate of sexual development resulting in the onset of egg laying earlier than that of control, but both the doses of steroid hormone suppressed ovarian development. It is suggested that, LH treatment not only induced a higher degree of reproductive development in short day quail but may also advance sexual maturity as under long daylength. Further, both the doses of male hormone had negative feedback effect on neuroendocrine axis and eliminated the attainment of scotorefractoriness i.e., reproductive development under short days.

Animals↗

PubMed2006

[The effects of flutamide on the full gene expression of early testis development of embryonic period male SD].

OBJECTIVE: To study the effects of Flutamide (Flu) on the full gene expression of early testis development of embryonic period in male SD rats. METHODS: Flu was injected subcutaneously (sc) with NS at doses of 6.25 mg/kg x d from 12th to 17th gestation days (GD), and in control group with tales doses NS. Fifty pregnant SD rats were sacrificed on GD 20. The mRNA were extracted respectively from fetus testis with treated and untreated Flu, then transcribed reversely to cDNA and labeled with cy5 and cy3 fluorescence. Subsequently, cDNA probes were hybridized to the Mouse40S cDNA microarray and fluorescence signals were analyzed. Meanwhile, we took out of the right testes of male offspring to make the detection of immunohistochemistry (IHC). Furthermore, we determined the level of testosterone by enzyme-linked immunosorbentassay (ELISA). RESULTS: Compared with the control group, a total of 31 identified genes expressed differently, including 14 down-regulated and 17 upregulated genes. However, the function of 5 down-regulated and 10 upregulated difference expression genes are unknown in Genbank. This finding has provided important reference basis for the molecular mechanism of reproductive development of Flu in the future. The activity of two important enzymes was cut down by IHC. The level of testosterone was decreased by ELISA. CONCLUSION: The results indicated that Flu administrated to F0 pregnant rats can damage apparently to the reproductive development of embryonic period male SD rats in many ways, and can cause the abnormality of sexual differentiation and sexual development in rats.

Androgen Antagonists↗

PubMed2002

Regulatory and drug development issues related to female sexual dysfunction.

Following the approval of sildenalfil for the treatment of erectile dysfunction, an increased awareness of and interest in female sexual dysfunction developed on the part of the academic and research communities as well as the pharmaceutical industry. This article will focus on regulatory issues related to the development of drug products to treat female sexual dysfunction and will describe a recently published drug development guidance document for this indication.

Clinical Trials as Topic↗

PubMed1996

Intersexuality in pigs: clinical, physiological and practical considerations.

Veterinary surgeons and practical pig farmers need to be aware of a condition that can have important deleterious consequences in a breeding herd. The animals in question have sometimes been referred to as hermaphrodites but would more correctly be termed intersexes. Whilst there is a complete spectrum of phenotypic sexual development within a population of such animals, the most common form is that of a putative female with a prominent up-turned vulva. Reflection of the vulval lips reveals a much-enlarged clitoris. There may be scrotal development, in conjunction with an enlarged penile and preputial sheath. Coarse hair and incipient tusk development may further indicate differing degrees of masculinization. Surgical exploration of intersex animals confirms a complete spectrum of gonadal types, ranging from 2 ovaries with a proportion of testicular tissue in one of them (i.e., an ovotestis) to 2, much-enlarged testicular-like structures with no detectable ovarian tissue. The gonads usually remain within the abdomen, but those with testicular tissue may descend to an inguinal or even scrotal location. The genital tract invariably comprises a bicornuate uterus, a partially vestigial Fallopian tube, and some development of one or both Wolffian ducts adjoining an ovotestis or testicular-like structure to form a convoluted epididymis. Spermatozoa are never present, either in abdominal or scrotal testicular tissue, nor are there any germ cells within the seminiferous tubules, only Sertoli-like cells. Due to the spectrum of gonadal types, sexual behaviour ranges from male-type aggressivity on the one hand to regular oestrous cycles on the other, with periods of standing oestrus during which intromission may be achieved. In animals with functional ovarian tissue in both gonads, foetal development has been observed, at least until days 25-30 of gestation. Almost all intersex pigs possess XX sex chromosomes and usually 36 autosomes; only a very small proportion are chimaeras or mosaics. Chromosome banding techniques have failed to demonstrate a portion of the Y chromosome translocated onto an X chromosome nor has molecular probing revealed the presence of the sex determining gene Sry or other classical Y-related DNA sequences, except in one instance. Breeding records suggest that the intersex condition results most frequently from the influence of an autosomal recessive gene carried by certain boars. Identification of such boars is therefore essential, as the incidence of intersexuality in their offspring may reach 4-5% or more. In terms of the pig industry, economic losses may result from: 1. Lack of fertility in intersex animals. 2. Aggressive behaviour in groups of growing/fattening pigs. 3. Boar taint in the carcase of animals possessing ovotestis. 4. Propagation of the deleterious condition, either by mating or more widely by artificial insemination.

Animals↗

PubMed2006

The politics of heterosexuality--a missing discourse in cancer nursing literature on sexuality: a discussion paper.

In this article, a critique of cancer nursing literature on the issue of sexuality is presented, with particular reference to literature on cancers common to women. The paper begins with an account of two competing perspectives on sexuality. The first is a version of sexuality rooted in sexology, underpinned by biomedical science that makes a claim to having identified 'normal' sexuality. The second is a version of sexuality developed within feminist scholarship that tends to reject biological determinism as a basis for understanding sexuality, instead favouring constructionist perspectives, with the socio-political context of sexual relations problematised. The focus of the article then shifts to cancer nursing literature on sexuality that deals primarily with cancers common to women, to appraise the extent to which either of the above perspectives on sexuality is invoked. Within this body of nursing knowledge, I argue that there has largely been an uncritical endorsement of biomedical constructions of sexuality, rooted in orthodox sexology, with a dominant focus on sexual functioning and on sexual rehabilitation for women with cancer. Moreover, in this knowledge base, phallocentric heterosexuality over and above other forms of sexual expression is privileged, and the socio-political context of unequal gender power relations is largely excluded. References to the social sphere as a dimension of nursing care are focused almost exclusively on maintaining normality, and reflect the emphasis on functional restoration. The largely individualistic, uncritical and biocentric emphasis in this literature may serve inadvertently to reinforce and maintain existing gender inequalities in heterosexual relationships. Finally, I consider the difficulties for oncology nurses in dealing with contradictory truth claims or conventional wisdoms about sexuality from the disparate disciplines of which holism is comprised.

Female↗

PubMed2003

A model for social control of sex change: interactions of behavior, neuropeptides, glucocorticoids, and sex steroids.

The optimal regulation of vertebrate sexual development and reproductive function involves integration of internal physiological signals, indicative of an individual's sexual status and capability for reproduction, with signals from the external environment. While these environmental cues are diverse, and oftentimes species-specific, the induction of sexual readiness is typically carried out through the same basic components of the hypothalamic-pituitary-gonadal axis conserved among vertebrates. Therefore, species exhibiting diverse patterns of reproduction can contribute to the understanding of the general mechanisms underlying the expression of adult sexual phenotypes. The bluehead wrasse, Thalassoma bifasciatum, is a tropical coral reef fish that displays social control of sex change, whereby dominant males inhibit sex change in other members of the social group using aggressive interactions. In many fish species and vertebrates in general, individuals that lose these interactions often experience increased serum glucocorticoids, which can have a subsequent impact on their physiology and behavior. We discuss glucocorticoid regulation of both neuropeptide gene transcription and the major steroid biosynthetic pathways as potential mechanisms involved in the regulation of sex change in the bluehead wrasse. We present a model describing behavioral regulation of sex change in the bluehead wrasse and then describe the potential mechanistic roles of glucocorticoids, gonadal steroids, and neuropeptides in generating the changes predicted by the model. Through the use of alternative model systems it is possible to observe novel interactions among the neuroendocrine axes that regulate major life history events, like reproduction. These insights may then shed light on similar functional mechanisms underlying behavioral regulation of reproduction in all vertebrates.

Animals↗