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PubMed2006

Colectomy with ileorectal anastomosis preserves female fertility in ulcerative colitis.

OBJECTIVES: Restorative proctocolectomy with ileoanal anastomosis (IPAA) is the surgical standard for patients with ulcerative colitis (UC). Significant reduction in female fertility and fecundity after IPAA has been shown in recent studies. In selected cases, colectomy with ileorectal anastomosis (IRA) is another surgical option. The aim of this study was to evaluate fertility in women with UC who underwent IRA. PATIENTS AND METHODS: This study included all women with UC who underwent IRA between 1962 and 1999 and who were 40 years old or younger at the time of surgery, and older than 18 years of age at the time of the interview. Data were collected using a structured telephone interview concerning reproductive behavior and waiting times to pregnancy. RESULTS: Among 40 eligible patients, 37 whose mean age at IRA was 28 years (range 11-39) answered the questionnaire. Twenty-two were unmarried, not wishful of pregnancy and/or already had children. Among 15 females wishing children after IRA, 10 (66%) became pregnant: one had therapeutic abortion, two had a miscarriage, four had 1 child, two had 2 children and one had 4 children. Five patients were sterile after IRA. CONCLUSION: These preliminary results suggest that IRA for UC preserves female fertility. If confirmed in other series this information should be provided to young women with UC before deciding surgical option.

Adult↗
PubMed1998

Sex and age differences of neurons expressing GABA-immunoreactivity in the rat bed nucleus of the stria terminalis.

Neurons, containing GABA were visualised immunohistochemically in the bed nucleus of the stria terminalis. Young prepubertal (20 days of age) and postpubertal (3 months and 1 year of age) Sprague-Dawley rats were used. Quantitative studies revealed greater density of GABA-immunoreactive perikarya in female than in male bed nucleus of the stria terminalis. This difference was not due to distribution in different volumes, since the volumes of the bed nucleus of the stria terminalis in the three ages studied did not differ by gender. Castration of new-born male rats caused elevation of the density of GABA-immunoreactive neurons in the bed nucleus of the stria terminalis to female levels on the third month of life. The percentage of nerve cells, expressing detectable amounts of GABA increased with age in the rat bed nucleus of the stria terminalis. The sexual dimorphism of GABA-immunoreactive neurons in the bed nucleus of the stria terminalis may contribute to the formation of reproductive behavior. The elevation of GABA expression with age might reflect change of the cellular activity in this part of the limbic circuitry.

Age Factors↗
PubMed2000

Binding characteristics of [3H]17beta-estradiol in the hypothalamus of juvenile rainbow trout, Oncorhynchus mykiss.

Gonadal steroids in the salmonid brain, acting through cellular receptors, may be responsible for the modulation of neuronal activity and organization of reproductive behaviors. We report our findings on the use of [3H]17beta-estradiol (E2) to identify intracellular estrogen receptors (ERs) in the hypothalamus of juvenile rainbow trout, Oncorhynchus mykiss. Specific binding (B(SP)) of [3H]E2 was tissue dependent between 0.5 and 2.25 hypothalamus equivalents for cytosol and nuclear extract preparations, respectively. B(SP) in cytosol fractions increased with time and reached maximum levels (4.18 nM) at 2.5 h incubation; by contrast, B(SP) in nuclear extract increased with time to achieve maximum levels (3.9 nM) by 2 h incubation. The association rate constants (k(+1)) for cytosol and nuclear extract preparations were 1.10 +/- 0.02 x 10(8) M(-1) min(-1) and 1.27 +/- 0.04 x 10(8) M(-1) min(-1), respectively. Equilibrium bound B(SP) dissociated from cytosol preparations with a half life (t1-2) of 42 min and a dissociation rate constant (k(-1)) of 1.01 +/- 0.03 min(-1). B(SP) dissociated from nuclear extract preparations with a t1-2 = 45 min and k(-1)= 0.92 +/- 0.01 min(-1) x B(SP) was saturable in both extract preparations with a calculated equilibrium dissociation constant (Kd) of 1.46 +/- 0.1 nM (cytosol) and 2.37 +/- 0.2 nM (nuclear), and a maximum number of binding sites (B(MAX)) of 50.85 +/- 3.2 fmol mg(-1) protein and 61.74 +/- 2.65 fmol mg(-1) protein, respectively. In both preparations, B(SP) was differentially displaced by structurally similar compounds with a rank order of potency of E2 > estrone > estriol > 17alpha-ethynyl estradiol > testosterone >> progesterone = tamoxifen >> cortisol > dexamethasone >> > beta-sitosterol. These properties of specifically bound [3H]E2 suggest the presence of an ER in the hypothalamus of juvenile rainbow trout comparable with ERs identified in salmonid liver.

Animals↗
PubMed1993

Anabolic steroids.

Anabolic steroids have been employed extensively in equine practice over the past 25 years. Their usefulness is largely dependent on subjective opinions, as only minimal studies have been carried out in horses. Therefore, their use will vary markedly between practitioners depending on their personal experiences and pressures by trainers to use them. They form part of rational therapy in a variety of conditions. In addition to use for increasing muscle mass, they are used to a varying extent in the raising of yearlings and in the training and racing of horses with the view of improving performance. However, in almost all countries, the latter use is largely curtailed, and the presence of these substances in postrace urine samples constitutes use of an illegal substance. To detect the use of anabolic steroids, including testosterone, sensitive ELISA tests for screening and GC/MS for confirmation have been developed. These compounds can be used safely. Risks can be encountered if too high doses are used, as horses may become difficult to manage due to increased aggressiveness and other stallion-like behavior. Reproductive efficiency in both stallions and mares may be temporarily impaired, but this is quite rapidly reversible following cessation of treatment.

Anabolic Agents↗
PubMed1996

Autoradiographic localization of receptors for neuropeptide Y (NPY) in the brain of broiler and leghorn chickens (Gallus domesticus).

Broiler and leghorn chickens show an extreme difference in ingestive and reproductive behavior. As neuropeptide Y (NPY) influences both behaviors the goal of this study was to elucidate the distribution, expression and affinity of NPY binding sites in broiler and leghorn chicken brain. By means of in vitro autoradiography, sections of chicken brains were incubated with 3H-NPY as tracer and NPY as displacer. Scatchard analysis revealed a curvilinear plot suggesting two subtypes of the NPY binding site in the chicken brain, a high affinity one (KD = 2-4 nM) and one with a lower affinity (KD = 18-24 nM). Binding sites for NPY are localized with high density in the different subdivisions of the neostriatum and the hyperstriatum, the cerebellum, the nucleus septalis lateralis and medialis, the nucleus ruber and the nucleus tractus solitarii. A lower density of NPY binding sites was found in the different subdivisions of the striatum, the nucleus mesencephalicus lateralis pars dorsalis, the paleostriatum, the archistriatum intermedium pars ventralis, the nucleus geniculatus lateralis, the nucleus taeniae, the locus ceruleus, the nucleus rotondus, the nucleus habenularis medialis, the nucleus dorsomedialis anterior (rostralis) thalami, the pituitary and the area of the hypothalamus with its nuclei such as the nucleus paraventricularis magnocellularis and the nucleus preopticus medialis. Comparison of the localization of NPY binding sites in the brains of broilers and leghorns showed no differences but the density of both receptor types is two to three times higher in broilers than in leghorns.

Animals↗
PubMed1999

Cholecystokinin-8-like-immunoreactive fibers in rat lumbosacral autonomic regions are sexually dimorphic and altered by a reduction of androgen receptors.

Cholecystokinin-8-like-immunoreactive (CCK-8-LI) fibers in laminae VII and X of the rat lumbosacral spinal cord demarcate the position of preganglionic autonomic neurons. This investigation reveals that adult male Sprague-Dawley, or King-Holtzman/Sprague-Dawley rats contain more CCK-8-LI fibers in lumbosacral laminae VII and X than adult females. Furthermore, testicular feminization mutation male rats (which lack 85-90% of their functional androgen receptors) contain fewer CCK-8-LI fibers than normal male or female rats, with the amount of CCK-8-LI being reduced to a greater extent in the sympathetic vs. the parasympathetic regions of the lumbosacral spinal cord. Thus, CCK-8-LI in testicular feminization mutation male rats has a distinctly female-like pattern. These results suggest that testosterone is a regulatory factor for CCK-8-LI fibers found in laminae VII and X of the lumbosacral spinal cord. Sexual dimorphism in lumbosacral CCK-8-LI fibers may contribute to modulating the final common pathway which differentially regulates the reproductive organs and stereotypic reproductive behavior, and may be involved with the sex differences described for pain.

Androgen-Insensitivity Syndrome↗
PubMed1997

A new multigene family of putative pheromone receptors.

The vomeronasal organ (VNO) mediates detection of pheromones related to social and reproductive behavior in most terrestrial vertebrates. We have identified a new multigene family of G protein-linked receptors (V2Rs) that are specifically expressed in the VNO. V2Rs have no significant homology to other putative pheromone receptors (V1Rs) or to olfactory receptors but are related to the Ca2+-sensing receptor and metabotropic glutamate receptors. V2Rs are expressed at high levels in small subpopulations of VNO neurons. V2Rs are primarily expressed in a different layer of VNO neurons from V1Rs, thus both gene families are likely to encode mammalian pheromone receptors.

Animals↗
PubMed2001

Smelling of odorous sex hormone-like compounds causes sex-differentiated hypothalamic activations in humans.

The anatomical pathways for processing of odorous stimuli include the olfactory nerve projection to the olfactory bulb, the trigeminal nerve projection to somatosensory and insular cortex, and the projection from the accessory olfactory bulb to the hypothalamus. In the majority of tetrapods, the sex-specific effects of pheromones on reproductive behavior is mediated via the hypothalamic projection. However, the existence of this projection in humans has been regarded as improbable because humans lack a discernable accessory olfactory bulb. Here, we show that women smelling an androgen-like compound activate the hypothalamus, with the center of gravity in the preoptic and ventromedial nuclei. Men, in contrast, activate the hypothalamus (center of gravity in paraventricular and dorsomedial nuclei) when smelling an estrogen-like substance. This sex-dissociated hypothalamic activation suggests a potential physiological substrate for a sex-differentiated behavioral response in humans.

Adult↗
PubMed2003

Steroid hormone production by parasites: the case of Taenia crassiceps and Taenia solium cysticerci.

Many examples of reciprocal endocrine interactions between parasites and hosts have been found in insects, arthropods and mammals. Cysticercosis produced by Taenia solium metacestodes is a widely distributed parasite infection that affects the human and the pig. Taenia crassiceps experimental murine cysticercosis has been used to explore the role of biological factors involved in host-parasite interactions. We had shown that T. crassiceps cysticercosis affects the serum concentration of steroid hormones and the reproduction behavior of the male mice host. In an effort to understand the biology of the parasite, we had investigated the parasite capacity to produce sex steroids. For this purpose, T. crassiceps cysticerci were incubated in the presence of different steroid precursors. TLC and recrystallization procedures showed that testosterone is produced from 3H-androstenedione in cysticerci. The conversion of 3H-testosterone to androstenedione, although present is much less significant. In addition, we had studied the production of testosterone by T. solium cysticerci. For this purpose, cysticerci were dissected from pork meat and incubated as above described. The results showed that T. solium cysticerci also produce testosterone. We have speculated about the importance of androgens in the growth of T. crassiceps cysticerci and found that the addition of the antiandrogen flutamide to the culture media of the parasites significantly decreased 3H-thymidine incorporation. We therefore hypothesized, that the ability of cysticerci to produce testosterone from steroid precursors might be important for the parasite growth and development.

Androgens↗
PubMedDate not supplied

A direct dopaminergic control of aromatase activity in the quail preoptic area.

In the quail preoptic area (POA) anatomical and pharmacological data suggest that catecholamines may be implicated in the control of testosterone (T) aromatization into estrogens. The biochemical mechanism(s) mediating this control of the enzyme activity is (are) however unexplored. The present studies were carried out to investigate whether the catecholamines, dopamine (DA) and norepinephrine (NE) are able to directly affect aromatase activity (AA) measured during in vitro incubations of POA homogenates. AA was quantified in the POA-hypothalamus of adult male Japanese quail by measuring the tritiated water production from [1beta-3H]-androstenedione. Enzyme activity was linear as a function of the incubation time and of the protein content of homogenates. It exhibited a typical Michaelis-Menten kinetics, with an apparent Km of 2.8 nM and a Vmax of 266.6 fmol h(-1) mg wet weight(-1). AA was then measured at a substrate concentration of 25 nM in the presence of catecholamines and some of their receptor agonists or antagonists, at two concentrations, 10(-3) and 10(-6) M. Norepinephrine and prazosin (alpha1-adrenergic antagonist) had no or very limited effects on AA at both concentrations. In contrast, DA and some D1 and/or D2 receptor agonists (apomorphine[D1/D2], SKF-38393 [D1] and RU-24213 [D2]) depressed AA by 40 to 70% at the 10(-3) M concentration. One D2 receptor antagonist also produced a major inhibition of AA (sulpiride) while other antagonists either had no significant effect or only produced moderate decreases in enzyme activity (SCH-23390 [D1], spiperone [D2], pimozide [D2]) as did two DA indirect agonists, amfonelic acid and nomifensine. The inhibitory effect of the agonists was not antagonized by the less active antagonists, SCH-23390 [D1] or spiperone [D2]. Taken together these results suggest that the inhibitory effects do not involve specific binding of DA or its agonists/antagonists to dopaminergic receptors mediating changes in cAMP concentration. This conclusion is also supported by the observation that addition of dibutyryl cAMP did not change brain AA. It appears more likely that DA and dopaminergic drugs inhibit AA by a direct effect on the enzyme, as suggested by the competitive nature of DA and SKF-38393 inhibition of AA (Ki's of 59 and 84 microM, respectively). The functional significance of this effect should still be demonstrated but this mechanism may represent an important physiological pathway through which neurotransmitters could rapidly affect steroid-dependent processes such as the neural synthesis of estrogens. This would provide a mean by which environmental stimuli could affect reproductive behavior and physiology.

Animals↗
PubMed2003

Requirement of the orphan nuclear receptor SF-1 in terminal differentiation of ventromedial hypothalamic neurons.

The ventromedial hypothalamic nucleus (VMN) is known to mediate autonomic responses in feeding and reproductive behaviors. To date, the most definitive molecular marker for the VMN is the orphan nuclear receptor steroidogenic factor-1 (SF-1). However, it is unclear whether SF-1 functions in the VMN as it does in peripheral endocrine organ development where loss of SF-1 results in organ agenesis due to apoptosis. Here, we provide evidence that SF-1 has a distinct role in later stages of VMN development by demonstrating the persistence of VMN precursors, the misexpression of an early marker (NKX2-1) concomitant with the absence of a late marker (BDNF neurotrophin), and the complete loss of projections to the bed nucleus of stria terminalis and the amygdala in sf-1 null mice. Our findings demonstrate that SF-1 is required for terminal differentiation of the VMN and suggest that transcriptional targets of SF-1 mediate normal circuitry between the hypothalamus and limbic structures in the telencephalon.

Amygdala↗
PubMed1998

Factors associated with recent and discontinued alcohol use by pregnant adolescents.

PURPOSE: To determine easily identifiable risk factors that differentiate pregnant adolescents who report recent (past 30 days) alcohol use and those who discontinue use by their first prenatal visit from those who deny consuming alcohol altogether. METHODS: A structured interview was completed by 378 adolescents < or = 17 years of age as part of standard care at our institution's adolescent obstetric clinic between July 7, 1992, and December 28, 1994. Using Chi-square or Student's t-tests, unique risk factors associated with recent or discontinued alcohol use in pregnancy were separately identified by comparing demographic, reproductive, behavioral, and environmental factors among recent users (n = 43), discontinued users (n = 48), and adolescents who denied ever using alcohol (n = 108). Significant indicators were then entered into stepwise logistic regression analyses to determine the most efficient models for predicting alcohol use. RESULTS: Partner alcohol use and use of alcohol during sexual activities were important risk factors for alcohol use by pregnant adolescents. Recent alcohol users were also more likely to be Mexican-American, to have quit school, and to report recent tobacco use, while adolescents who stopped using alcohol during pregnancy were significantly more likely to have witnessed or been a victim of or known a victim of violence. CONCLUSIONS: Screening at the first prenatal visit for these unique and easily assessed factors will help clinicians identify adolescents at greatest risk for alcohol use during pregnancy.

Adolescent↗
PubMed1998

Adolescent males involved in pregnancy: associations of forced sexual contact and risk behaviors.

PURPOSE: To determine whether sexually active adolescent males who report being the victim of forced sexual contact and engaging in health risk and problem behaviors are more likely to report getting someone pregnant. METHODS: In 1995, 4159 students in Grades 9-12 in 59 randomly selected public high schools in Massachusetts were anonymously surveyed using the Youth Risk Behavior Survey (YRBS). Data were analyzed for 824 sexually active males. Demographic variables and indicators of sexual behavior, pregnancy, violence, and suicide were assessed. Data were analyzed with multiple logistic regression. RESULTS: A total of 12.0% of sexually active males reported having been involved in a pregnancy. The proportion of males who reported getting a partner pregnant increased with age. Of the sample, 8.1% gave a history of having had sexual contact against their will. Of those who reported forced sexual contact, 36.4% reported having been involved in a pregnancy; of the males who did not report a history of forced sexual contact, 9.4% were involved in a pregnancy (CV = 0.23; p < 0.00001). Based on multiple logistic regression, forced sexual contact [odds ratio (OR) 3.56; 95% confidence interval (CI) 1.79-7.09], frequency of weapon carrying on school property (OR 1.39; 95% CI 1.18-1.64), number of cigarettes smoked per day (OR 1.22; 95% CI 1.08-1.38), number of sexual partners in the previous 3 months (OR 1.43; 95% CI 1.25-1.65), and condom nonuse at last intercourse (OR 1.80; 95% CI 1.06-3.02) correctly classified 89.9% of the males who were involved in a pregnancy. CONCLUSION: This study highlights the association between health-risk and problem behaviors, forced sexual contact, and involvement in pregnancy among sexually active male high school students. In our analysis, a history of forced sexual contact was associated with a higher risk of high school males' involvement in pregnancy. These results strongly suggest the importance of screening sexually active males for a history of forced sexual intercourse and health risk and problem behaviors in the effort to prevent teenage pregnancy and childbearing.

Adolescent↗
PubMed1999

High school athletic participation, sexual behavior and adolescent pregnancy: a regional study.

PURPOSE: To determine whether high school athletic participation among adolescents in Western New York was associated with reduced rates of sexual behavior and pregnancy involvement. METHODS: A secondary analysis of data from the Family and Adolescent Study, a longitudinal study of a random sample of adolescents (ages 13-16 years) from 699 families living in households in Western New York. A general population sample was obtained with characteristics closely matching the census distributions in the area. Interview and survey methods provided data on athletic participation, frequency of sexual relations during the past year, and risk for pregnancy. Bivariate correlations were used to examine relationships among athletic participation, demographic and control variables, and measures of sexual behavior and pregnancy rates. Next, path analyses were done in order to test for hypothesized relationships between athletic participation, sexual behavior, and pregnancy involvement while controlling for age, race, income, family cohesion, and non-athletic forms of extracurricular activity. Variables that were significantly associated with sexual behavior and/or pregnancy involvement were presented for both sexes within the resulting multivariate models. RESULTS: Lower income and higher rates of sexual activity were associated with higher rates of pregnancy involvement for both sexes. Family cohesion was associated with lower sexual activity rates for both sexes. For girls, athletic participation was directly related to reduced frequency of sexual behavior and, indirectly, to pregnancy risk. Male athletes did not exhibit lower rates of sexual behavior and involvement with pregnancy than male non-athletes. Boys who participated in the arts, however, did report lower rates of sexual behavior and, indirectly, less involvement with pregnancy. CONCLUSIONS: Female adolescents who participated in sports were less likely than their non-athletic peers to engage in sexual activity and/or report a pregnancy. Among male adolescents, athletic participation was unrelated to sexual behavior and pregnancy involvement. Teen pregnancy prevention efforts for girls should consider utilizing sport as a strategic tool.

Adolescent↗