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Steroid signaling activation and intracellular localization of sex steroid receptors.  

Science.gov (United States)

In addition to stimulating gene transcription, sex steroids trigger rapid, non-genomic responses in the extra-nuclear compartment of target cells. These events take place within seconds or minutes after hormone administration and do not require transcriptional activity of sex steroid receptors. Depending on cell systems, activation of extra-nuclear signaling pathways by sex steroids fosters cell cycle progression, prevents apoptosis, leads to epigenetic modifications and increases cell migration through cytoskeleton changes. These findings have raised the question of intracellular localization of sex steroid receptors mediating these responses. During the past years, increasing evidence has shown that classical sex steroid receptors localized in the extra-nuclear compartment or close to membranes of target cells induce these events. The emerging picture is that a process of bidirectional control between signaling activation and sex steroid receptor localization regulates the outcome of hormonal responses in target cells. This mechanism ensures cell cycle progression in estradiol-treated breast cancer cells, and its derangement might occur in progression of human proliferative diseases. These findings will be reviewed here together with unexpected examples of the relationship between sex steroid receptor localization, signaling activation and biological responses in target cells. We apologize to scientists whose reports are not mentioned or extensively discussed owing to space limitations. PMID:21234121

Giraldi, Tiziana; Giovannelli, Pia; Di Donato, Marzia; Castoria, Gabriella; Migliaccio, Antimo; Auricchio, Ferdinando

2010-12-01

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Sex Steroids and Breast Cancer: An Overview  

Directory of Open Access Journals (Sweden)

Full Text Available Sex steroids, also known as sex hormones are synthesized naturally by the gonads (ovaries or testes. The two main classes of sex steroids, androgens and estrogens, are crucial hormones for the proper development and function of the body; they regulate sexual differentiation, the secondary sex characteristics, and sexual habits. They are also well known to influence many common cancers, especially hormonally driven cancers such as breast and prostate cancer. In this report, we review the association of sex steroids with cancer and the potential use of endocrine manipulation in cancer therapy as well as the limitations and challenges faced in this field.

Zeina Nahleh

2013-05-01

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Sex Steroids and Breast Cancer: An Overview  

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Sex steroids, also known as sex hormones are synthesized naturally by the gonads (ovaries or testes). The two main classes of sex steroids, androgens and estrogens, are crucial hormones for the proper development and function of the body; they regulate sexual differentiation, the secondary sex characteristics, and sexual habits. They are also well known to influence many common cancers, especially hormonally driven cancers such as breast and prostate c...

Zeina Nahleh; Arenas, Juan E.; Arafat Tfayli

2013-01-01

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Sex Steroid Effects at Target Tissues: Mechanisms of Action  

Science.gov (United States)

This review outlines new advances in our understanding of the spectrum of steroid hormone ligands, newly recognized target tissues, structure-function relationships of steroid receptors, and, finally, their genomic and nongenomic actions. Sex-based specific effects are often related to the different steroid hormone mileu in men compared with women. Understanding the mechanisms of sex steroid action gives insight into the differences in normal physiology and disease states.

Margaret E. Wierman (University of Colorado Veterans Affairs Medical Center)

2007-03-01

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Developmental synergism of steroidal estrogens in sex determination.  

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Gonadal sex in the red-eared slider turtle, Trachemys scripta, is determined by incubation temperature during embryonic development. Evidence suggests that temperature determines sex by influencing steroid hormone metabolism and/or sensitivity: steroidogenic enzyme inhibitors or exogenous sex steroid hormones and their man-made analogs override (or enhance) temperature effects on sex determination. Specifically, nonaromatizable androgens and aromatase inhibitors induce testis differentiation ...

Bergeron, J. M.; Willingham, E.; Osborn, C. T.; Rhen, T.; Crews, D.

1999-01-01

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The influence of sex steroids on pineal enzymes  

International Nuclear Information System (INIS)

The influence of the gonadal sex steroids namely, estradiol, progesterone and testosterone on the two major enzymes responsible for the synthesis of melatonin in the pineal gland was investigated. These enzymes are Serotonin-N-acetyltransferase (SNAT) and Hydroxyindole-O-methyltransferase (H10MT). Testosterone was found to be the only sex steroid capable of influencing SNAT activity whereas all three of the sex steroids were found to influence H10MT activity in a biphasic dose-dependent manner. The influence of these sex steroids on radiolabelled serotonin metabolism by pineals in organ culture was also investigated. Ovariectomy, castration and the sex steroids were all found to alter the pattern of the radiolabelled serotonin metabolism by these pineal glands in organ culture

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NEUROPROTECTIVE EFFECTS OF FEMALE SEX STEROIDS IN CEREBRAL ISCHEMIA  

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The central and peripheral nervous system are important targets of sex steroids. Sex steroids affect the brain development and differentiation, and influence neuronal functions. Recent evidence emphasizes a striking sex-linked difference in brain damage after experimental stroke, as well as the efficacy of hormones in treating cerebral stroke injury. Several different models ofcerebral ischemia have been utilized for hormone neuroprotection studies, including transient or permanent middle cer...

Dra?a Sanja

2013-01-01

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Body fatness and sex steroid hormone concentrations in US men: results from NHANES III  

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OBJECTIVE: Obesity is associated with a variety of chronic diseases, including cancer, which may partly be explained by its influence on sex steroid hormone concentrations. Whether different measures of obesity, i.e., body mass index (BMI), waist circumference, and percent body fat were differentially associated with circulating levels of sex steroid hormones was examined in 1,265 men, aged 20-90+ years old, attending the morning examination session of the Third National Health and Nutrition...

Rohrmann, S.; Shiels, M. S.; Lopez, D. S.; Rifai, N.; Nelson, W. G.; Kanarek, N.; Guallar, E.; Menke, A.; Joshu, C. E.; Feinleib, M.; Sutcliffe, S.; Platz, E. A.

2011-01-01

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The roles of sex steroid receptor coregulators in cancer  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Sex steroid hormones, estrogen, progesterone and androgen, play pivotal roles in sex differentiation and development, and in reproductive functions and sexual behavior. Studies have shown that sex steroid hormones are the key regulators in the development and progression of endocrine-related cancers, especially the cancers of the reproductive tissues. The actions of estrogen, progesterone and androgen are mediated through their cognate intracellular receptor proteins, the estrogen receptors (ER, the progesterone receptors (PR and the androgen receptor (AR, respectively. These receptors are members of the nuclear receptor (NR superfamily, which function as transcription factors that regulate their target gene expression. Proper functioning of these steroid receptors maintains the normal responsiveness of the target tissues to the stimulations of the steroid hormones. This permits the normal development and function of reproductive tissues. It can be inferred that factors influencing the expression or function of steroid receptors will interfere with the normal development and function of the target tissues, and may induce pathological conditions, including cancers. In addition to the direct contact with the basal transcription machinery, nuclear receptors enhance or suppress transcription by recruiting an array of coactivators and corepressors, collectively named coregulators. Therefore, the mutation or aberrant expression of sex steroid receptor coregulators will affect the normal function of the sex steroid receptors and hence may participate in the development and progression of the cancers.

Loggie Brian W

2002-11-01

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NEUROPROTECTIVE EFFECTS OF FEMALE SEX STEROIDS IN CEREBRAL ISCHEMIA  

Directory of Open Access Journals (Sweden)

Full Text Available The central and peripheral nervous system are important targets of sex steroids. Sex steroids affect the brain development and differentiation, and influence neuronal functions. Recent evidence emphasizes a striking sex-linked difference in brain damage after experimental stroke, as well as the efficacy of hormones in treating cerebral stroke injury. Several different models ofcerebral ischemia have been utilized for hormone neuroprotection studies, including transient or permanent middle cerebral artery occlusion, transient global ischemia, and transient forebrain ischemia. Extensive experimental studies have shown that female sex steroids such as progesterone and 17ß-estradiol exert neuroprotective effects in the experimental models of stroke, although deleterious effects have also been reported. Also, a significance of numerous factors, including gender and age of experimental animals, localization of brain lesion, duration of ischemia and precise dose of steroids has been pointed out. There are multiple potential mechanisms that might be invoked to explain the beneficial effects of female sex steroids in brain injury, involving neuroprotection, anti-inflammatory properties, effects on vasculature and altered transcriptional regulation. A several clinical trials on the effects of sex hormones to traumatic brain injury have been performed, suggesting that hormone therapy may represent a new therapeutic tool to combat certain diseases, such as traumatic brain injury. Further basic science studies and randomized clinical trials are necessary to reveal a potential application of these molecules as a new therapeutic strategy.

Dra?a Sanja

2013-01-01

11

Sex steroid modulation of cortisol secretion in sheep.  

Science.gov (United States)

There is strong evidence that the gonads modulate the hypothalamic-pituitary-adrenal axis. To investigate these sex differences at the adrenal glands of sheep we compared the cortisol response to ACTH (experiment 1) and measured the relative expression of oestrogen receptor alpha (ERS1), androgen receptor (AR), melanocortin 2 receptor (MC2R) and steroid acute regulatory protein (STAR) mRNA in adrenal glands (experiment 2) of gonadectomised rams and ewes either with or without sex steroid replacement. In experiment 1 six castrated adult rams and four ovariectomised adult ewes were used in two ACTH trials. On each trial blood samples were taken every 15 min for 4 h through an indwelling jugular catheter and each animal received 0.5 mg of an ACTH analogue i.v., immediately after the sample at 1 h from the beginning of the trial. Four days after the first trial the males received 100 mg of Testosterone Cyclopentilpropionate (TC) i.m. and the females received 2.5 mg of Oestradiol Benzoate (EB) i.m. At 72 h after TC or EB administration the second trial was performed. In experiment 2 the adrenal glands were obtained from gonadectomised adult rams (n=8) and adult ewes (n=8). Four rams received 100 mg of TC i.m. and four females received 0.5 mg of EB i.m. Blood samples were taken at 0, 12, 24, 48 and 72 h relative to steroid replacement and the animals were thereafter slaughtered. Cortisol, testosterone and 17?-oestradiol were determined by radioimmunoanalysis. The transcripts of ERS1, AR, MC2R and STAR were determined by real-time reverse transcription PCR in adrenal tissue. Cortisol secretion was higher in female sheep than in male sheep, and higher in EB-treated than non-treated ewes. No difference in cortisol secretion was observed between TC-treated and non-treated rams. Gonadectomised rams treated with TC presented greater AR mRNA and MC2R mRNA expression than males without the steroid replacement. Gonadectomised ewes treated with EB tended to present lower AR mRNA than the ones without steroid replacement. Gonadectomised rams with TC also had greater AR mRNA, ERS1 mRNA and MC2R mRNA expression than ewes treated with EB. The relative amount of STAR transcript was not different among the different groups. The results confirm sex differences in ACTH-induced cortisol secretion in sheep, as well as in the expression of the receptor proteins for both 17?-oestradiol and testosterone in the sheep adrenal gland. However, the underlying mechanisms for sex steroid modulation remain unresolved. PMID:24703387

van Lier, E; Carriquiry, M; Meikle, A

2014-06-01

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Sex steroids and food intake in fish  

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This study was conducted to test the sensitivity to gonadal steroids of the systems regulating food intake in sea bass. Animals were treated with silastic implants containing 17-?-estradiol or testosterone. Self-feeding was recorded for 31 days using computerized demand feeders and unfed-pellet recovery systems. Both steroids strongly decreased selffeeding levels, feed efficiency and specific growth rates. The linear growth of fish treated with testosterone was higher than in 17-?-estradiol...

Leal, Esther; Sa?nchez, Elisa; Muriach, Borja; Cerda?-reverter, Jose? Miguel

2009-01-01

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An abridged history of sex steroid hormone receptor action.  

Science.gov (United States)

The field of steroid hormone action is well established, although it is barely more than four decades old. Pivotal experiments in the late 1950s and 1960s showed that hormone-binding components exist within nuclei of target tissues and that steroid hormones act by regulating gene expression, rather than directly influencing enzymatic processes. The understanding that steroid hormone receptors interact with the general transcription machinery and alter chromatin structure came in the 1970s and 1980s, and details of this mechanism continue to be elucidated. In addition, the discovery of rapid cellular responses to steroid hormones has led to the identification of putative membrane-bound steroid receptors that act without affecting gene transcription. As noted in the recent Institute of Medicine report "Exploring the Biological Contributions to Human Health: Does Sex Matter?", the effects of steroid hormones and defects in steroid hormone receptor action have a profound impact on human health and disease. Future research directives include the development of potent, selective steroid receptor modulators, the elucidation of nongenomic steroid hormone effects, and further exploration of hormone-genome interactions. PMID:11568172

Fannon, S A; Vidaver, R M; Marts, S A

2001-10-01

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Sex steroid metabolism in the placenta and the breast  

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Abstract The biosynthesis and metabolism of sex steroids are controlled by a series of steroidogenic enzymes. In the placenta and the breast, 3?-hydroxysteroid dehydrogenase type 1 (3?-HSD1) is essential for the synthesis of all steroid hormones by catalyzing pregnenolone to progesterone (P) or dehydroepiandrosterone (DHEA) to androstenedione (A-dione). P450 aromatase (P450arom) converts androgens to estrogens and is therefore critical for estrogen production. 17?-hydroxysteroid dehydro...

Li, Yan

2004-01-01

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Evidence for Geographical and Racial Variation in Serum Sex Steroid Levels in Older Men  

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Background: Despite considerable racial and geographical differences in human phenotypes and in the incidence of diseases that may be associated with sex steroid action, there are few data concerning variation in sex steroid levels among populations. We designed an international study to determine the degree to which geography and race influence sex steroid levels in older men. Methods: Using mass spectrometry, concentrations of serum androgens, estrogens, and sex steroid precursors/metabolit...

Orwoll, Eric S.; Nielson, Carrie M.; Labrie, Fernand; Barrett-connor, Elizabeth; Cauley, Jane A.; Cummings, Steven R.; Ensrud, Kristine; Karlsson, Magnus; Lau, Edith; Leung, P. C.; Lunggren, Osten; Mellstro?m, Dan; Patrick, Alan L.; Stefanick, Marcia L.; Nakamura, Kozo

2010-01-01

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DHHC-7 and -21 are palmitoylacyltransferases for sex steroid receptors.  

Science.gov (United States)

Classical estrogen, progesterone, and androgen receptors (ERs, PRs, and ARs) localize outside the nucleus at the plasma membrane of target cells. From the membrane, the receptors signal to activate kinase cascades that are essential for the modulation of transcription and nongenomic functions in many target cells. ER, PR, and AR trafficking to the membrane requires receptor palmitoylation by palmitoylacyltransferase (PAT) protein(s). However, the identity of the steroid receptor PAT(s) is unknown. We identified the DHHC-7 and -21 proteins as conserved PATs for the sex steroid receptors. From DHHC-7 and -21 knockdown studies, the PATs are required for endogenous ER, PR, and AR palmitoylation, membrane trafficking, and rapid signal transduction in cancer cells. Thus the DHHC-7 and -21 proteins are novel targets to selectively inhibit membrane sex steroid receptor localization and function. PMID:22031296

Pedram, Ali; Razandi, Mahnaz; Deschenes, Robert J; Levin, Ellis R

2012-01-01

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Regucalcin expression in bovine tissues and its regulation by sex steroid hormones in accessory sex glands.  

Science.gov (United States)

Regucalcin (RGN) is a mammalian Ca2+-binding protein that plays an important role in intracellular Ca2+ homeostasis. Recently, RGN has been identified as a target gene for sex steroid hormones in the prostate glands and testis of rats and humans, but no studies have focused on RGN expression in bovine tissues. Thus, in the present study, we examined RGN mRNA and protein expression in the different tissues and organs of veal calves and beef cattle. Moreover, we investigated whether RGN expression is controlled through sex steroid hormones in bovine target tissues, namely the bulbo-urethral and prostate glands and the testis. Sex steroid hormones are still illegally used in bovine husbandry to increase muscle mass. The screening of the regulation and function of anabolic sex steroids via modified gene expression levels in various tissues represents a new approach for the detection of illicit drug treatments. Herein, we used quantitative PCR, western blot and immunohistochemistry analyses to demonstrate RGN mRNA and protein expression in bovine tissues. In addition, estrogen administration down-regulated RGN gene expression in the accessory sex glands of veal calves and beef cattle, while androgen treatment reduced RGN gene expression only in the testis. The confirmation of the regulation of RGN gene expression through sex steroid hormones might facilitate the potential detection of hormone abuse in bovine husbandry. Particularly, the specific response in the testis suggests that this tissue is ideal for the detection of illicit androgen administration in veal calves and beef cattle. PMID:25415588

Starvaggi Cucuzza, Laura; Divari, Sara; Mulasso, Chiara; Biolatti, Bartolomeo; Cannizzo, Francesca T

2014-01-01

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Regucalcin Expression in Bovine Tissues and Its Regulation by Sex Steroid Hormones in Accessory Sex Glands  

Science.gov (United States)

Regucalcin (RGN) is a mammalian Ca2+-binding protein that plays an important role in intracellular Ca2+ homeostasis. Recently, RGN has been identified as a target gene for sex steroid hormones in the prostate glands and testis of rats and humans, but no studies have focused on RGN expression in bovine tissues. Thus, in the present study, we examined RGN mRNA and protein expression in the different tissues and organs of veal calves and beef cattle. Moreover, we investigated whether RGN expression is controlled through sex steroid hormones in bovine target tissues, namely the bulbo-urethral and prostate glands and the testis. Sex steroid hormones are still illegally used in bovine husbandry to increase muscle mass. The screening of the regulation and function of anabolic sex steroids via modified gene expression levels in various tissues represents a new approach for the detection of illicit drug treatments. Herein, we used quantitative PCR, western blot and immunohistochemistry analyses to demonstrate RGN mRNA and protein expression in bovine tissues. In addition, estrogen administration down-regulated RGN gene expression in the accessory sex glands of veal calves and beef cattle, while androgen treatment reduced RGN gene expression only in the testis. The confirmation of the regulation of RGN gene expression through sex steroid hormones might facilitate the potential detection of hormone abuse in bovine husbandry. Particularly, the specific response in the testis suggests that this tissue is ideal for the detection of illicit androgen administration in veal calves and beef cattle. PMID:25415588

Starvaggi Cucuzza, Laura; Divari, Sara; Mulasso, Chiara; Biolatti, Bartolomeo; Cannizzo, Francesca T.

2014-01-01

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Influence of sex and oral contraceptive steroids on paracetamol metabolism.  

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Paracetamol metabolism was investigated in eight healthy males, eight healthy females and eight healthy females receiving oral contraceptive steroids (OCS). Paracetamol clearance was 22% greater in males compared to the control female group. This difference was entirely due to increased activity of the glucuronidation pathway in males, there being no sex-related differences in the sulphation or oxidative metabolism of paracetamol. Paracetamol clearance in females using OCS was 49% greater tha...

Miners, J. O.; Attwood, J.; Birkett, D. J.

1983-01-01

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No sex difference in yolk steroid concentrations of avian eggs at laying  

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Yolk steroids of maternal origin have been proposed to influence genetic sex determination in birds, based on sex differences in yolk steroid concentrations of peafowl eggs incubated for 10 days. More recent reports dispute this proposal, as yolk steroids in eggs incubated for 3 days do not show such sex differences. To date, research examining this phenomenon has only analysed incubated eggs, although sex in avian species is determined before incubation begins. This may be a serious methodol...

Pilz, Kevin M.; Adkins-regan, Elizabeth; Schwabl, Hubert

2005-01-01

 
 
 
 
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Probing the impact of sex steroids and menopause-related sex steroid deprivation on modulation of immune senescence.  

Science.gov (United States)

Immune senescence denotes the general decline in immune system function, characterized by a reduced immune response and an increased inflammatory state. Menopause is a natural change in a women's life, the menopause-related low estrogen levels affecting many body functions, among them the immune system. Numerous human studies with menopausal women and animal models with surgically induced menopause show a clear impact of sex steroids in immune responses. Female superiority in vaccination response and predisposition to infections are eliminated after menopause, while during menopause inflammatory cytokines such as Tumor Necrosis Factor-? (TNF-?), Interleukins-1?, 6, 8 and 13 (IL-1?, IL-6, IL-8, IL-13) and Monocyte Chemoattractant Protein-1 (MCP-1) are increased, implying a molecular connection of sex steroid loss with immune senescence. Moreover, immune cells modify their number and function after the menopausal transition, this offering another explanation for immune senescence. Until now most of the existing studies have concluded that menopause plays an additional role to aging in immune senescence. While it is clear that we are as yet far from thoroughly understanding the molecular pathways connecting sex steroids and menopause with immune senescence, such knowledge is highly likely to enable future targeted interventions in treatment and prevention of age-related diseases in women. PMID:24852404

Vrachnis, Nikolaos; Zygouris, Dimitrios; Iliodromiti, Zoe; Daniilidis, Angelos; Valsamakis, Georgios; Kalantaridou, Sophia

2014-07-01

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Serum sex steroids, gonadotrophins and sex hormone-binding globulin in prostatic hyperplasia  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Benign prostatic hyperplasia (BPH develops in elderly males when serum androgens are relatively lower than in healthy younger males, but it is not well understood whether and how sex steroids are altered in prostatic hyperplasia. It is also uncertain whether there is any change in sex steroid levels in males older than 40 years of age. The use of androgens in elderly males is often discouraged because of the probable worsening effect of androgens on prostatism. This study aimed to determine the relationship between prostatic hyperplasia and sex steroid levels and whether there is any significant change in these hormones after the age of 40 years. Subjects and Methods: We studied healthy males of age 240 years with (n=92 or without (n=93 clinical prostatic hyperplasia. Serum testosterone, estradiol, gonadotrophins and sex hormone-binding globulin (SHBG were compared. The hormones and SHBG were also correlated with age. Results: No significant difference was found in any hormone in cases with prostatic hyperplasia as compared with the controls. There was no significant age-related change in any hormone except estradiol where as a negative correlation (P< .003 with age was found. Conclusions: Serum sex steroids and SHBG remained unchanged in symptomatic prostatic hyperplasia and except for estradiol there was no significant age-related change in serum testosterone, gonadotrophins and SHBG in healthy males after the fourth decade. More studies are needed to confirm the age-related decline of estrogens in males.

Ansari Mohammad Abdul

2008-01-01

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Serum-sex steroids, gonadotrophins and sex hormone-binding globulin inprostatic hyperplasia  

International Nuclear Information System (INIS)

Benign prostatic hyperplasia (BPH) develops in elderly males when serumandrogens are relatively lower than in healthy younger males, but is not wellunderstood whether and how sex steroids are altered in prostatic hyperplasia.It is also uncertain that whether there is any change in sex steroids levelsin males older than 40 years of age. The use of androgens in elderly males isoften discouraged because of the probable worsening effect of androgens onprostatism. This study aimed to determine the relationship between prostatichyperplasia and sex steroid levels and whether there is any significantchange in these hormones after the age of 40 years. We studied healthy malesof >40 years with (n=92) or without (n=93) clinical prostatic hyperplasia.Serum testosterone, estradiol, gonadotrophins and sex hormone-bindingglobulin (SHBG) were compared. The hormones and SHGB were also correlatedwith age. No significant difference was found in any hormone in cases withprostatic hyperplasia as compared with the controls. There was no significantage-related change in any hormone except estradiol where as a negativecorrelation (P<0.003) with age was found. Serum sex steroids and SHGBremained unchanged in symptomatic prostatic hyperplasia and except forestrdoil there was no significant age-related change in serum testosterone,gonadotrophins and SHGB in healthy males after the fourth decade. Morestudies are needed to confirm the age-related decline of estrogens in males.(author)of estrogens in males.(author)

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Factors That Contribute to Assay Variation in Quantitative Analysis of Sex Steroid Hormones Using Liquid and Gas Chromatography-Mass Spectrometry  

Science.gov (United States)

The list of physiological events in which sex steroids play a role continues to increase. To decipher the roles that sex steroids play in any condition requires high quality cohorts of samples and assays that provide highly accurate quantitative measures. Liquid and gas chromatography coupled with mass spectrometry (LC-MS and GC-MS) have…

Xu, Xia; Veenstra, Timothy D.

2012-01-01

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Assessment of circulating sex steroid levels in prepubertal and pubertal boys and girls by a novel ultrasensitive gas chromatography-tandem mass spectrometry method  

DEFF Research Database (Denmark)

Estrogens and androgens play key roles for pubertal onset and sexual maturation. Most currently used immunoassays are not sensitive enough to accurately measure the low circulating levels of sex steroids in children without any signs of puberty. However, this does not exclude that sex steroids have important biological roles in prepubertal children.

Courant, Frédérique; Aksglæde, Lise

2010-01-01

26

The Effects of Sex Steroids on Spatial Performance: A Review and an Experimental Clinical Investigation.  

Science.gov (United States)

Investigated the relationship between sex hormones and spatial performance among adolescents treated with sex steroids for delayed puberty. Found that spatial performance varied according to gender but did not vary with levels of actively circulating sex steroids. Reviewed physiological mechanisms, developmental periods, and past empirical work…

Liben, Lynn S.; Susman, Elizabeth J.; Finkelstein, Jordan W.; Chinchilli, Vernon M.; Kunselman, Susan; Schwab, Jacqueline; Dubas, Judith Semon; Demers, Laurence M.; Lookingbill, Georgia; D'Arcangelo, M. Rose; Krogh, Holleen R.; Kulin, Howard E.

2002-01-01

27

Measurement of Urinary Steroids; The Methods Which  

Directory of Open Access Journals (Sweden)

Full Text Available 17 - Ketosteroids, 17-ketogenic steroids and 17-Hydroxy -corticosteroids, the major and clinically important urinary stero¬ids are largly originated from adrenal cortex and in some extent from gonads. These steroids have been and still are measured by Zimmerman and Porter-Silber colorimetric methods. At the time these measurements were considered highly valuable replacement for time consuming bioassays. Unfortunately, none of these assays are reliable indicator of the biological activity of specific steroids secreted by the endocrine glands. Therefore, considering such deficiencies and improvement techniques with higher sensi¬tivity and specificity for endocrine evaluation, it seems that colorimetric assays should be abandoned. In this article the disadvantages of these assays are described and new methods for evaluation of steroids are introduced.

M.G. Bigdeli M. Ahmadi

1990-07-01

28

Sex-steroid imbalance in females and dry eye.  

Science.gov (United States)

Abstract Dry eye (DE) is a multifactorial disorder of the ocular surface unit that results in eye discomfort, visual disturbance and ocular surface damage. It is one of the most common complaints in daily ophthalmic practice. The risk of DE increases with age in both sexes, while its incidence is higher among females. In addition, the condition of menopause in aging women may also contribute to DE onset or worsening as a consequence of an overall hormonal imbalance. Sex hormones play a key role in ocular surface physiology and they impact differently on ocular surface tissues. Reduced estrogen levels were historically thought to be responsible in age-related DE onset but more recent investigations have reconsidered the role of androgens that are present and exert a protective function on the ocular surface. Hormone levels themselves, withdrawal changes in hormone levels, and the changes in hormone-receptor responsiveness are all important factors but it remains to be fully elucidated how estrogen or androgen insufficiency act alone or together in a combined imbalance or interplay to raise the risk of disease. The purpose of this review is to briefly outline current scientific evidence on the influence of androgens and estrogens, on the Lachrymal and Meibomian glands and on ocular surface epithelia including conjunctival goblet cells during reproductive and menopausal periods. The role of sex steroids is also discussed in relation to the pathogenesis of different forms of DE and Sjogren's syndrome (SS). The impact of systemic hormone therapy (HT) in DE post-menopausal women still appears as a controversial issue, despite the many clinical studies. Finally, the outcomes of topical applications of steroid-based products are summarized, underlying the need for potential (tear) biomarker(s) in the rationale of DE-targeted therapy. PMID:25290221

Versura, Piera; Giannaccare, Giuseppe; Campos, Emilio C

2015-02-01

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Augmented transport and metabolism of sex steroids in lymphoid neoplasia in the rat  

Energy Technology Data Exchange (ETDEWEB)

Sex steroid hormones have been shown to influence a number of biological properties of lymphoid neoplastic tissue. Receptor occupancy is a function of the pool size of cellular exchangeable hormone therefore it is important to understand the mechanisms regulating hormone transport from the microcirculation and hormone metabolism. In this study, steroid hormone transport and metabolism were investigated in control and neoplastic lymph nodes after transplanting control rats with the WR-6 leukemic line. Steroid hormone transport and metabolism were studied after pulse labeling the nodal tissue in vivo with arterial bolus injections of (/sup 3/H)testosterone. Residual vascular radioactivity was monitored by simultaneously injecting 113m indium chelated to bovine transferrin. Both testosterone and estradiol were partially available for transport through the capillary barriers of control and neoplastic lymph nodes from the circulating albumin-bound pool. Estradiol was readily available for transport from the circulating sex hormone-binding globulin-bound pool in both control and neoplastic lymph nodes. Testosterone was not available for transport from the sex hormone-binding globulin-bound pool in control lymph nodes, but was readily available for transport in metastatic lymph nodes. Thaw-mount autoradiography and physiological measurements showed that plasma proteins such as albumin or transferrin were confined to the microcirculation compartment. The transport of protein-bound hormones into lymph node represents a mechanism of enhanced steroid hormone dissociation from the binding protein without the plasma protein per se significantly exiting the microcirculation compartment. Metabolic studies showed no measurable metabolism of (/sup 3/H)testosterone in the control lymph nodes by 60 sec after arterial injection.

Cefalu, W.T.; Pardridge, W.M.

1987-03-01

30

Augmented transport and metabolism of sex steroids in lymphoid neoplasia in the rat  

International Nuclear Information System (INIS)

Sex steroid hormones have been shown to influence a number of biological properties of lymphoid neoplastic tissue. Receptor occupancy is a function of the pool size of cellular exchangeable hormone therefore it is important to understand the mechanisms regulating hormone transport from the microcirculation and hormone metabolism. In this study, steroid hormone transport and metabolism were investigated in control and neoplastic lymph nodes after transplanting control rats with the WR-6 leukemic line. Steroid hormone transport and metabolism were studied after pulse labeling the nodal tissue in vivo with arterial bolus injections of [3H]testosterone. Residual vascular radioactivity was monitored by simultaneously injecting 113m indium chelated to bovine transferrin. Both testosterone and estradiol were partially available for transport through the capillary barriers of control and neoplastic lymph nodes from the circulating albumin-bound pool. Estradiol was readily available for transport from the circulating sex hormone-binding globulin-bound pool in both control and neoplastic lymph nodes. Testosterone was not available for transport from the sex hormone-binding globulin-bound pool in control lymph nodes, but was readily available for transport in metastatic lymph nodes. Thaw-mount autoradiography and physiological measurements showed that plasma proteins such as albumin or transferrin were confined to the microcirculation compartment. The transport of proculation compartment. The transport of protein-bound hormones into lymph node represents a mechanism of enhanced steroid hormone dissociation from the binding protein without the plasma protein per se significantly exiting the microcirculation compartment. Metabolic studies showed no measurable metabolism of [3H]testosterone in the control lymph nodes by 60 sec after arterial injection

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All sex steroids are made intracellularly in peripheral tissues by the mechanisms of intracrinology after menopause.  

Science.gov (United States)

Following the arrest of estradiol secretion by the ovaries at menopause, all estrogens and all androgens in postmenopausal women are made locally in peripheral target tissues according to the physiological mechanisms of intracrinology. The locally made sex steroids exert their action and are inactivated intracellularly without biologically significant release of the active sex steroids in the circulation. The level of expression of the steroid-forming and steroid-inactivating enzymes is specific to each cell type in each tissue, thus permitting to each cell/tissue to synthesize a small amount of androgens and/or estrogens in order to meet the local physiological needs without affecting the other tissues of the organism. Achieved after 500 million years of evolution, combination of the arrest of ovarian estrogen secretion, the availability of high circulating levels of DHEA and the expression of the peripheral sex steroid-forming enzymes have permitted the appearance of menopause with a continuing access to intratissular sex steroids for the individual cells/tissues without systemic exposure to circulating estradiol. In fact, one essential condition of menopause is to maintain serum estradiol at biologically inactive (substhreshold) concentrations, thus avoiding stimulation of the endometrium and risk of endometrial cancer. Measurement of the low levels of serum estrogens and androgens in postmenopausal women absolutely requires the use of MS/MS-based technology in order to obtain reliable accurate, specific and precise assays. While the activity of the series of steroidogenic enzymes can vary, the serum levels of DHEA show large individual variations going from barely detectable to practically normal "premenopausal" values, thus explaining the absence of menopausal symptoms in about 25% of women. It should be added that the intracrine system has no feedback elements to adjust the serum levels of DHEA, thus meaning that women with low DHEA activity will not be improved without external supplementation. Exogenous DHEA, however, follows the same intracrine rules as described for endogenous DHEA, thus maintaining serum estrogen levels at substhreshold or biologically inactive concentrations. Such blood concentrations are not different from those observed in normal postmenopausal women having high serum DHEA concentrations. Androgens, on the other hand, are practically all made intracellularly from DHEA by the mechanisms of intracrinology and are always maintained at very low levels in the blood in both pre- and postmenopausal women. Proof of the importance of intracrinology is also provided, among others, by the well-recognized benefits of aromatase inhibitors and antiestrogens used successfully for the treatment of breast cancer in postmenopausal women where all estrogens are made locally. Each medical indication for the use of DHEA, however, requires clinical trials performed according to the FDA guidelines and the best rules of clinical medicine. PMID:24923731

Labrie, Fernand

2015-01-01

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Seasonal Changes in Gonadotropins, Prolactin and Sex Steroid Hormones in Captive Hill Mynah Gracula religiosa  

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In the present study seasonal changes of gonadotropins, prolactin and sex steroid hormones in captive Hill Mynah were measured from October 1995 to September 1996. During the breeding season, these hormone levels were higher than during the non-breeding one. Plasma levels of FSH in males and females rose in December, prior to the onset of breeding and remained elevated throughout the breeding season except in May. LH, testosterone and estradiol in both sexes were elevated in January, th...

Manee Archawaranon

2006-01-01

33

Modulation of the cytosolic androgen receptor in striated muscle by sex steroids  

Science.gov (United States)

The influence of orchiectomy (GDX) and steroid administration on the level of the cytosolic androgen receptor in the rat levator ani muscle and in rat skeletal muscles (tibialis anterior and extensor digitorum longus) was studied. Androgen receptor binding to muscle cytosol was measured using H-3 methyltrienolone (R1881) as ligand, 100 fold molar excess unlabeled R1881 to assess nonspecific binding, and 500 fold molar excess of triamcinolone acetonide to prevent binding to glucocorticoid and progestin receptors. Results demonstrate that modification of the levels of sex steroids can alter the content of androgen receptors of rat striated muscle. Data suggest that: (1) cytosolic androgen receptor levels increase after orchiectomy in both levator ani muscle and skeletal muscle; (2) the acute increase in receptor levels is blocked by an inhibitor of protein synthesis; and (3) administration of estradiol-17 beta to castrated animals increases receptor binding in levator ani muscle but not in skeletal muscle.

Rance, N. E.; Max, S. E.

1982-01-01

34

Sex differences in ?-amyloid accumulation in 3xTg-AD mice: Role of neonatal sex steroid hormone exposure  

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The risk of Alzheimer’s disease (AD) is higher in women than in men, a sex difference that likely results from the effects of sex steroid hormones. To investigate this relationship, we first compared progression of ?-amyloid (A?) pathology in male and female triple transgenic (3xTg-AD) mice. We found that female 3xTg-AD mice exhibit significantly greater A? burden and larger behavioral deficits than age-matched males. Next, we evaluated how the organizational effects of sex steroid hormo...

Carroll, Jenna C.; Rosario, Emily R.; Kreimer, Sara; Villamagna, Angela; Gentzschein, Elisabet; Stanczyk, Frank Z.; Pike, Christian J.

2010-01-01

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Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones  

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We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17?-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

2012-12-01

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Steroid Hormone Measurement in Epidemiological Studies  

Science.gov (United States)

July 17, 2014 10:30 AM - 11:30 AM Shady Grove, Room TE406 + Add to Outlook Calendar Speaker: Neal E. Craft, Ph.D. President Craft Technologies, Inc. Print This Page Steroid Hormone Measurement in Epidemiological Studies DCEG Seminar News & Events

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Measurement of steroid concentrations in brain tissue: methodological considerations  

Directory of Open Access Journals (Sweden)

Full Text Available It is well recognized that steroids are synthesized de novo in the brain (neurosteroids. In addition, steroids circulating in the blood enter the brain. Steroids play numerous roles in the brain, such as influencing neural development, behavior, neuroplasticity, and inflammation. In order to understand the regulation and functions of steroids in the brain, it is important to directly measure steroid concentrations in brain tissue. In this brief review, we discuss methods for the detection and quantification of steroids in the brain. We concisely present the major advantages and disadvantages of different technical approaches at various experimental stages: euthanasia, tissue collection, steroid extraction, steroid separation, and steroid measurement. We discuss, among other topics, the potential effects of anesthesia and saline perfusion prior to tissue collection; microdissection via Palkovits punch; solid phase extraction; chromatographic separation of steroids; and immunoassays and mass spectrometry for steroid quantification, particularly the use of mass spectrometry for “steroid profiling.” Finally, we discuss the interpretation of local steroid concentrations, such as comparing steroid levels in brain tissue with those in the circulation (plasma vs. whole blood samples; total vs. free steroid levels. This brief review highlights some of the major methodological considerations at multiple experimental stages and provides a broad framework for designing studies that examine local steroid levels in the brain as well as other tissues.

MatthewDTaves

2011-09-01

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The plasma sex steroid profiles in the freshwater, sex-reversing teleost fish, Monopterus albus (Zuiew).  

Science.gov (United States)

The plasma levels of both the free and conjugated forms of six sex steroids (androstenedione, testosterone, 11-oxotestosterone, 11 beta-hydroxytestosterone, estrone, and 17 beta-estradiol) were determined by radioimmunoassay combined with Celite chromatography in different sexual phases of the protogynous Monopterus albus throughout the reproductive cycle. The amounts of 11-oxotestosterone and 11 beta-hydroxytestosterone were found to be very low and variable in all the specimens investigated. No conjugated 17 beta-estradiol or free estrone was detected. Female individuals showed a prespawning rise of androstenedione which subsequently dropped to a low level in the spawning period. The estrogen levels in the female phase were found to be higher than those in all other sexual phases during the spawning period, but the testosterone level remained constant throughout the reproductive cycle in the female phase. The level of androstenedione was highest in the early intersexual and mid-intersexual phases during the postspawning/inactive period. Compared with the female specimens in the same reproductive period, the early intersexual individuals showed a higher level of 17 beta-estradiol, while the mid-intersexual animals showed a higher level of testosterone in the postspawned/inactive period. In the mid-intersexual phase, the levels of androstenedione, testosterone, 17 beta-estradiol, and estrone dropped progressively in relation to the seasonal reproductive cycle. The male fish had a constant level of androstenedione, estrone, and 17 beta-estradiol. However, the level of testosterone increased as the spawning period approached. The hormonal profile in the late intersexual phase was essentially similar to that in the male phase. The changes in the plasma levels of sex steroids in M. albus apparently were related to the maturation of the female and male sex tissues and to their seasonal reproductive cycle. PMID:3817447

Yeung, W S; Chan, S T

1987-02-01

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Sex steroids, precursors and metabolites deficiencies in men with isolated hypogonadotropic hypogonadism and panhypopituitarism: a GCMS-based comparative study.  

Science.gov (United States)

Context: Both testicular and adrenal steroid secretions are impaired in men with panhypopituitarism (Hypo-Pit), whereas only testicular steroid secretion is impaired in men with isolated gonadotropin deficiency (IHH) caused by normosmic congenital hypogonadotropic hypogonadism (nCHH) or Kallmann syndrome (KS). Objective: To compare serum levels of sex steroids, precursors and metabolites between men with complete IHH and those with Hypo-Pit. Patients: We studied 42 healthy men, 16 untreated men with IHH (nCHH/KS) and 23 men with Hypo-Pit (14 with craniopharyngioma, 9 with congenital hypopituitarism) receiving hydrocortisone, thyroxin and GH replacement therapy but not testosterone. Methods: Gas chromatography/mass spectrometry (GCMS) was used to measure serum levels of sex steroids (testosterone (T), dihydrotestosterone (DHT), and estradiol (E2)), their precursors (pregnenolone, 17hydroxy-pregnenolone, dehydroepiandrosterone, androstenediol, progesterone, 17hydroxy-progesterone, androstenedione) and their metabolites (androsterone, estrone, estrone sulfate), as well as pregnenolone and DHEA sulfate esters (PREGS and DHEAS). Results: All the above-mentioned steroids, and notably T, DHT and E2, were significantly lower in IHH patients than in controls but remained well above the detection limit of the relevant assays. In Hypo-Pit men, all these steroids were dramatically and significantly lower than in IHH. Interestingly, T, DHT and E2, as well as PREGS and DHEAS, were undetectable or barely detectable in Hypo-Pit men. Conclusions: Steroid deficiencies are marked but partial in men with complete IHH. In contrast, men with Hypo-Pit have a very severe overall steroid deficiency. These deficiencies could affect health and quality of life. PMID:25393641

Giton, Frank; Trabado, Séverine; Maione, Luigi; Sarfati, Julie; Le Bouc, Yves; Brailly-Tabard, Sylvie; Fiet, Jean; Young, Jacques

2014-11-13

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Lack of effects of beta-carotene on lipids and sex steroid hormones in hyperlipidemics.  

Science.gov (United States)

Beta-carotene in doses of up to 300 mg daily raises high-density lipoprotein cholesterol levels within 2 to 4 weeks in healthy subjects. The authors, in this study, investigate the short-term effects of high-dose beta-carotene upon serum lipids, lipoproteins, and selected sex steroid hormones in 59 adult patients with Type IIa or IIb hyperlipidemia and 36 healthy subjects. Volunteers took beta-carotene (300 mg) or wheat germ oil capsules daily for 30 days. Lipids were measured on days 1, 14, 21, and 30. Beta-carotene, retinol, free and total testosterone, and estradiol levels were measured on days 1 and 30. Total high-density lipoprotein cholesterol levels increased 10% (p < 0.01) over baseline in all groups by day 14 but returned to baseline by day 30. Total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels transiently increased between days 14 and 21 by up to 9%, 8%, and 20%, respectively, only in the patients with hyperlipidemia treated with beta-carotene, but returned to baseline on day 30. Apolipoproteins A and B were unchanged. Despite 20-fold increases of plasma beta-carotene levels there, were no reports of carotenodermia and no alteration in sex steroid hormones, retinol levels, hepatic transaminases, or persistent changes in serum lipids that were attributable to beta-carotene. PMID:8010332

Hughes, G S; Ringer, T V; Francom, S F; Means, L K; DeLoof, M J

1994-07-01

 
 
 
 
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No effect of sex steroids on compensatory muscle hypertrophy  

Science.gov (United States)

The effects of orchiectomy and/or subcutaneously implanted testosterone propionate (TP) on the hypertrophic response of rat plantaris muscles to functional overload (induced by bilateral removal of gastrocnemius and soleus muscles) are investigated experimentally. Muscle wet weight, metabolic substrate oxidation, and cytosolic androgen-receptor binding are measured, and the results are presented in tables. Eight weeks after surgery, the plantaris muscle weight as a percentage of body weight is found to be about twice that in rats without muscle overload, regardless of the sex-hormone status. Overloading causes decreased ability to oxidize glucose and pyruvate, decreased succinate dehydrogenase specific activity, and no change in the ability to oxidize beta-hydroxybutyrate or in androgen-receptor binding. The oxidative response is unaffected by orchiectomy or TP or both. It is argued that the actions of sex hormones and functional overload are not synergistic.

Max, S. R.; Rance, N. E.

1984-01-01

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Sex, sex steroids, and diabetic cardiomyopathy: making the case for experimental focus.  

Science.gov (United States)

More than three decades ago, the Framingham study revealed that cardiovascular risk is elevated for all diabetics and that this jeopardy is substantially accentuated for women in particular. Numerous studies have subsequently documented worsened cardiac outcomes for women. Given that estrogen and insulin exert major regulatory effects through common intracellular signaling pathways prominent in maintenance of cardiomyocyte function, a sex-hormone:diabetic-disease interaction is plausible. Underlying aspects of female cardiovascular pathophysiology that exaggerate cardiovascular diabetic risk may be identified, including increased vulnerability to coronary microvascular disease, age-dependent impairment of insulin-sensitivity, and differential susceptibility to hyperglycemia. Since Framingham, considerable progress has been made in the development of experimental models of diabetic disease states, including a diversity of genetic rodent models. Ample evidence indicates that animal models of both type 1 and 2 diabetes variably recapitulate aspects of diabetic cardiomyopathy including diastolic and systolic dysfunction, and cardiac structural pathology including fibrosis, loss of compliance, and in some instances ventricular hypertrophy. Perplexingly, little of this work has explored the relevance and mechanisms of sexual dimorphism in diabetic cardiomyopathy. Only a small number of experimental studies have addressed this question, yet the prospects for gaining important mechanistic insights from further experimental enquiry are considerable. The case for experimental interrogation of sex differences, and of sex steroid influences in the aetiology of diabetic cardiomyopathy, is particularly compelling-providing incentive for future investigation with ultimate therapeutic potential. PMID:23792676

Reichelt, Melissa E; Mellor, Kimberley M; Bell, James R; Chandramouli, Chanchal; Headrick, John P; Delbridge, Lea M D

2013-09-15

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Analysis of In Vitro Effects of Sex Steroids on Lymphocyte Responsiveness in Murrah Buffaloes (Bubalus bubalis)  

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Present study was carried out on forty four apparently healthy Murrah buffaloes of different age groups of both sexes to investigate the effects of sex steroids on cell mediated immunity in vitro. Estrogen inhibited proliferation in mitogen-stimulated lymphocytes from prepubertal but not post pubertal buffaloes of either sex. Estrogen at 100?pg/mL concentration stimulating the proliferation significantly (P < 0.05). in all groups and had higher stimulatory effect in lymphocytes from day 10 ...

Zahoor Ahmad Pampori; Sujata Pandita

2012-01-01

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Intracrine sex steroid synthesis and signaling in human epidermal keratinocytes and dermal fibroblasts.  

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Peripheral intracrine sex steroid synthesis from adrenal precursors dehydroepiandrosterone (DHEA) and DHEA-sulfate has evolved in humans. We sought to establish if there are differences in intracrine, paracrine, and endocrine regulation of sex steroids by primary cultures of human skin epidermal keratinocytes and dermal fibroblasts. Microarray analysis identified multifunctional genes modulated by steroids, quantitative RT-PCR (qRT-PCR) mRNA expression, enzymatic assay aromatase activity, scratch assay cell migration, immunocytochemistry ?-smooth muscle actin (?-SMA), and collagen gel fibroblast contraction. All steroidogenic components were present, although only keratinocytes expressed the organic anion organic anion transporter protein (OATP) 2B1 transporter. Both expressed the G-protein-coupled estrogen receptor (GPER1). Steroids modulated multifunctional genes, up-regulating genes important in repair and aging [angiopoietin-like 4 (ANGPTL4), chemokine (C-X-C motif) ligand 1 (CXCL1), lamin B1 (LMNB1), and thioredoxin interacting protein (TXNIP)]. DHEA-sulfate (DHEA-S), DHEA, and 17?-estradiol stimulated keratinocyte and fibroblast migration at early (4 h) and late (24-48 h) time points, suggesting involvement of genomic and nongenomic signaling. Migration was blocked by aromatase and steroid sulfatase (STS) inhibitors confirming intracrine synthesis to estrogen. Testosterone had little effect, implying it is not an intermediate. Steroids stimulated fibroblast contraction but not ?-SMA expression. Mechanical wounding reduced fibroblast aromatase activity but increased keratinocyte activity, amplifying the bioavailability of intracellular estrogen. Cultured fibroblasts and keratinocytes provide a biologically relevant model system to investigate the complex pathways of sex steroid intracrinology in human skin.-Pomari, E., Valle, L. D., Pertile, P., Colombo, L., and Thornton, M. J. Intracrine sex steroid synthesis and signaling in human epidermal keratinocytes and dermal fibroblasts. PMID:25392269

Pomari, Elena; Valle, Luisa Dalla; Pertile, Paolo; Colombo, Lorenzo; Thornton, M Julie

2015-02-01

45

Sex hormone binding globulin and corticosteroid binding globulin as major effectors of steroid action.  

Science.gov (United States)

Contrary to the long-held postulate of steroid-hormone binding globulin action, these protein carriers of steroids are major players in steroid actions in the body. This manuscript will focus on our work with sex hormone binding globulin (SHBG) and corticosteroid binding globulin (CBG) and demonstrate how they are actively involved in the uptake, intracellular transport, and possibly release of steroids from cells. This manuscript will also discuss our own findings that the steroid estradiol is taken up into the cell, as demonstrated by uptake of fluorescence labeled estradiol into Chinese hamster ovary (CHO) cells, and into the cytoplasm where it may have multiple actions that do not seem to involve the cell nucleus. This manuscript will focus mainly on events in two compartments of the cell, the plasma membrane and the cytoplasm. PMID:24269740

Caldwell, Jack D; Jirikowski, Gustav F

2014-03-01

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Seasonal Changes in Gonadotropins, Prolactin and Sex Steroid Hormones in Captive Hill Mynah Gracula religiosa  

Directory of Open Access Journals (Sweden)

Full Text Available In the present study seasonal changes of gonadotropins, prolactin and sex steroid hormones in captive Hill Mynah were measured from October 1995 to September 1996. During the breeding season, these hormone levels were higher than during the non-breeding one. Plasma levels of FSH in males and females rose in December, prior to the onset of breeding and remained elevated throughout the breeding season except in May. LH, testosterone and estradiol in both sexes were elevated in January, the onset of breeding. The maximum levels of these hormones were coincident with development of the gonads, secondary sex characters, territorial aggression and sexual behavior. Plasma testosterone and estradiol titers in males and females respectively were evidently bimodal with peaks in January and April which corresponded to the norm of two clutches per breeding season of this species. Progesterone levels in females surged in March, April and May which was the period of egg laying and incubation. Circulating prolactin in females was high during the parental phase of the breeding cycle in April and June. In addition, social cues such as sexual partner and external stimuli such as eggs or nestlings influenced the reproductive endocrinology.

Manee Archawaranon

2006-01-01

47

Interaction of blood sex steroid-binding globulin-steroid complexes with the plasma membranes of cells of the human decidual endometrium  

International Nuclear Information System (INIS)

The plasma membranes of cells of the decidual tissue specifically bind complexes of the sex steroid-binding globulin (SBG) of the blood with estrogens (estradiol, estriol, estrone) and the pharmacological agent danazol but do not interact with SBG-testosterone and SBG-dihydrotestosterone complexes. The selectivity of the interaction of SBG-steroid complexes with the cell membranes of the decidual tissue confirms the hypothesis of an active role of SBG in the action of steroids on this target tissue

48

The sensitivity of the child to sex steroids: possible impact of exogenous estrogens  

DEFF Research Database (Denmark)

The current trends of increasing incidences of testis, breast and prostate cancers are poorly understood, although it is assumed that sex hormones play a role. Disrupted sex hormone action is also believed to be involved in the increased occurrence of genital abnormalities among newborn boys and precocious puberty in girls. In this article, recent literature on sex steroid levels and their physiological roles during childhood is reviewed. It is concluded that (i) circulating levels of estradiol in prepubertal children are lower than originally claimed; (ii) children are extremely sensitive to estradiol and may respond with increased growth and/or breast development even at serum levels below the current detection limits; (iii) no threshold has been established, below which no hormonal effects can be seen in children exposed to exogenous steroids or endocrine disruptors; (iv) changes in hormone levels during fetal and prepubertal development may have severe effects in adult life and (v) the daily production rates of sex steroids in children estimated by the Food and Drug Administration in 1999 and still used in risk assessments are highly overestimated and should be revised. Because no lower threshold for estrogenic action has been established, caution should be taken to avoid unnecessary exposure of fetuses and children to exogenous sex steroids and endocrine disruptors, even at very low levels.

Aksglaede, Lise; Juul, Anders

2006-01-01

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Sex Steroid Modulation of Fatty Acid Utilization and Fatty Acid Binding Protein Concentration in Rat Liver  

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The mechanism by which sex steroids influence very low density hepatic lipoprotein triglyceride production has not been fully elucidated. In previous studies we showed that [14C]oleate utilization and incorporation into triglycerides were greater in hepatocyte suspensions from adult female rats than from males. The sex differences were not related to activities of the enzymes of triglyceride biosynthesis, whereas fatty acid binding protein (FABP) concentration in liver cytosol was greater in ...

Ockner, Robert K.; Lysenko, Nina; Manning, Joan A.; Monroe, Scott E.; Burnett, David A.

1980-01-01

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Steroid hormones, receptors, and perceptual and cognitive sex differences in the visual system.  

Science.gov (United States)

Abstract The actions of gonadal steroid hormones induce morphological sex differences in many tissues in the body, including brain. These occur either during development to organize tissues in a sex-specific pattern and/or in adulthood to activate specific cellular pathways. Cellular and morphological changes in the brain, induced by androgens and estrogens, underlie behavioral sex differences in both reproductive and non-reproductive behaviors, including visual perception. A growing body of evidence indicates that some sex differences related to visual perception arise as the result of the organizational actions of gonadal steroid hormones on cerebral cortical pathways involved in visual processing of objects and movement. This review addresses the influence of gonadal steroids on structural, biochemical and morphological changes in tissues in the brain and body. These effects are extended to consider how gonadal hormone effects may contribute to cognitive sex differences across species that are related to processing within the dorsal and ventral visual streams for motion and objects, respectively. Lastly, this review considers the question of how cognitive sex differences related to processing of movement and objects in humans may be reflective of two types of cognitive style that are only superficially related to gender. PMID:25153712

Handa, Robert J; McGivern, Robert F

2015-02-01

51

Secondary osteoporosis due to sickle cell anemia: Do sex steroids play a role?  

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Full Text Available Background : The exact cause of osteoporosis in patients with sickle cell disease (SCD is not known, and various hypotheses have been put forward. Aim: To assess the effect of sex steroids on bone mass in SCD patients. Settings and Design: In King Fahd Hospital of the university, Alkhobar, Saudi Arabia, a cross-sectional study was carried out. Materials and Methods : All patients known to suffer from SCD attending the hospital between August 2006 and August 2007 were subjects of the study. Blood was extracted for serum level of androgens, gonadotropins, thyroid stimulating hormone (TSH, calcium, phosphorus, and alkaline phosphatase. Measurement of bone mineral density (BMD of hip and spine was done using dual-energy X-ray absorptiometry (DEXA. All tests were performed using SPSS (Statistical Package for Social Sciences, version 14.0, Chicago, Illinois, with P value of < 0.05 being statistically significant with confidence interval (CI of 95%. Results : One hundred three consecutive patients with an average age of 27.83 years were studied. Forty-five were males; and 58, females. Low bone mass (osteoporotic/osteopenic was found in 62.2% of the patients in the male group and 67.06% in the female group. In males, testosterone level was not significant between different groups, but total estradiol levels were significantly lower in the osteopenic and osteoporotic patients (P < 0.003 and < 0.01 respectively. In female patients, estradiol and testosterone levels were lower in osteoporotic patients in comparison to non-osteoporotic patients (P = 0.05 and 0.001. Conclusions : Our study indicates that sex steroids play a major role in the development of osteopenia and osteoporosis in patients with SCD

Sadat-Ali Mir

2008-05-01

52

The mechanisms underlying sexual differentiation of behavior and physiology in mammals and birds: relative contributions of sex steroids and sex chromosomes  

Directory of Open Access Journals (Sweden)

Full Text Available From a classical viewpoint, sex-specific behavior and physiological functions as well as the brain structures of mammals such as rats and mice, have been thought to be influenced by perinatal sex steroids secreted by the gonads. Sex steroids have also been thought to affect the differentiation of the sex-typical behavior of a few members of the avian order Galliformes, including the Japanese quail and chickens, during their development in ovo. However, recent mammalian studies that focused on the artificial shuffling or knockout of the sex-determining gene, Sry, have revealed that sex chromosomal effects may be associated with particular types of sex-linked differences such as aggression levels, social interaction, and autoimmune diseases, independently of sex steroid-mediated effects. In addition, studies on naturally occurring, rare phenomena such as gynandromorphic birds and experimentally constructed chimeras in which the composition of sex chromosomes in the brain differs from that in the other parts of the body, indicated that sex chromosomes play certain direct roles in the sex-specific differentiation of the gonads and the brain. In this article, we review the relative contributions of sex steroids and sex chromosomes in the determination of brain functions related to sexual behavior and reproductive physiology in mammals and birds.

FumihikoMaekawa

2014-08-01

53

Sex change and steroid profiles in the protandrous anemonefish Amphiprion melanopus (Pomacentridae, Teleostei).  

Science.gov (United States)

Plasma profiles of several gonadal steroids and cortisol were examined in a field population of the protandrous, sex-changing anemonefish Amphiprion melanopus to elucidate potential roles of these hormones in gonadal sex change. Sex change was experimentally induced in males by removal of their dominant female pair mates. These sex-changing males were captured and sampled at 5, 10, or 20 days after female removal. Unmanipulated males and females were also sampled. Males had higher plasma levels of 11-ketotestosterone (11-KT) than did females, but had lower levels of androstenedione (Ad), testosterone (T), and estradiol-17 beta (E2). The three androgens showed decreases from male levels at 10 days, then an increasing trend at 20 days after female removal. E2 levels exhibited no changes from male levels until 20 days, when a significant increase over male levels was observed. Mature females had higher levels of Ad, T, and E2 than the 20-day treatment group, indicating that these steroids continue to rise after Day 20. The results support hypothesized roles for androgens in male function and E2 in female function in A. melanopus. However, E2 increases lagged behind oogonial proliferation, arguing against an influence of this steroid in the initiation of female function. Cortisol levels did not differ between males and females, but exhibited an increase during sex change, peaking at 20 days. PMID:8405900

Godwin, J R; Thomas, P

1993-08-01

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Peripheral vs. central sex steroid hormones in experimental Parkinson’s disease  

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Full Text Available The nigrostriatal dopaminergic (NSDA pathway degenerates in Parkinson’s disease (PD, which occurs with approximately twice the incidence in men than women. Studies of the influence of systemic estrogens in females suggest sex hormones contribute to these differences. In this review we analyse the evidence revealing great complexity in the response of the healthy and injured NSDA system to hormonal influences, and emphasize the importance of centrally generated estrogens. At physiological levels, circulating estrogen (in females or estrogen precursors (testosterone in males, aromatised to estrogen centrally have negligible effects on dopaminergic neurone survival in experimental PD, but can modify striatal dopamine levels via actions on the activity or adaptive responses of surviving cells. However, these effects are sexually dimorphic. In females, estradiol promotes adaptive responses in the partially injured NSDA pathway, preserving striatal dopamine, whereas in males gonadal steroids and exogenous estradiol have a negligible or even suppressive effect, effectively exacerbating dopamine loss. On balance, the different effects of gonadal factors in males and females contribute to sex differences in experimental PD. Fundamental sex differences in brain organization, including the sexually dimorphic networks regulating NSDA activity are likely to underpin these responses. In contrast, estrogen generated locally appears to preserve striatal dopamine in both sexes. The available data therefore highlight the need to understand the biological basis of sex-specific responses of the NSDA system to peripheral hormones, so as to realise the potential for sex-specific, hormone-based therapies in PD. Furthermore, they suggest that targeting central steroid generation could be equally effective in preserving striatal dopamine in both sexes. Clarification of the relative roles of peripheral and central sex steroid hormones is thus an important challenge for future studies.

SimonMcArthur

2011-11-01

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Skeletal muscle and bone: effect of sex steroids and aging  

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Both estrogen and testosterone are present in males and females. Both hormones contribute to the well being of skeletal muscle and bone in men and women, and there is evidence that the loss of sex hormones is associated with the age-related decline in bone and skeletal muscle mass. Hormonal supplementation of older adults to restore estrogen and testosterone levels to those of young men and women is not without penalty.

PhD Marybeth Brown (University of Missouri-Columbia Dept of Physical Therapy)

2008-02-14

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Role of sex steroid receptors in pathobiology of hepatocellular carcinoma  

Directory of Open Access Journals (Sweden)

Full Text Available The striking gender disparity observed in the incidence of hepatocellular carcinoma (HCC suggests an important role of sex hormones in HCC pathogenesis. Though the studies began as early as in 1980s, the precise role of sex hormones and the significance of their receptors in HCC still remain poorly understood and perhaps contribute to current controversies about the potential use of hormonal therapy in HCC. A comprehensive review of the existing literature revealed several shortcomings associated with the studies on estrogen receptor (ER and androgen receptor (AR in normal liver and HCC. These shortcomings include the use of less sensitive receptor ligand binding assays and immunohistochemistry studies for ER? alone until 1996 when ER? isoform was identified. The animal models of HCC utilized for studies were primarily based on chemical-induced hepatocarcinogenesis with less similarity to virus-induced HCC pathogenesis. However, recent in vitro studies in hepatoma cells provide newer insights for hormonal regulation of key cellular processes including interaction of ER and AR with viral proteins. In light of the above facts, there is an urgent need for a detailed investigation of sex hormones and their receptors in normal liver and HCC. In this review, we systematically present the information currently available on androgens, estrogens and their receptors in normal liver and HCC obtained from in vitro, in vivo experimental models and clinical studies. This information will direct future basic and clinical research to bridge the gap in knowledge to explore the therapeutic potential of hormonal therapy in HCC.

Mamta Kalra, Jary Mayes, Senait Assefa, Anil K Kaul, Rashmi Kaul

2008-10-01

57

Postmenopausal serum sex steroids and risk of hormone receptor positive and negative breast cancer: a nested case-control study  

DEFF Research Database (Denmark)

Pre-diagnostic endogenous sex steroid hormone levels have well established associations with overall risk of breast cancer. While evidence towards the existence of distinct subtypes of breast cancer accumulates, few studies have investigated the associations of sex steroid hormone levels with risk of hormone receptor (estrogen (ER) and/or progesterone receptor (PR)) defined breast cancer. In a case-control study nested within the EPIC cohort (European Prospective Investigation into Cancer and Nutrition), estradiol, testosterone and sex hormone binding globulin levels were measured in pre-diagnostic serum samples from postmenopausal women not using HRT at blood donation. 554 women who developed invasive breast cancer with information on receptor status were matched with 821 control subjects. Conditional logistic regression models estimated breast cancer risk with hormone concentrations according to hormone receptor status of the tumor. Sex steroid hormones were associated with risks of not only ER+PR+ breast cancer [estradiol OR for highest versus lowest tertile=2.91 (95%CI:1.62-5.23), Ptrend0.002; testosterone OR=2.27 (95%CI:1.35-3.81), Ptrend=0.002] but also of ER-PR- breast cancer [estradiol OR=2.11 (95%CI:1.00-4.46), Ptrend =0.05; testosterone OR= 2.06 (95%CI:0.95-4.46), Ptrend=0.03], with associations appearing somewhat stronger in the receptor positive disease. Serum androgens and estrogens are associated with risks of both hormone receptor negative as well as receptor positive breast tumors. Further research is needed to establish through which molecular pathways, and during which evolutionary stages of development, androgens and estrogens can promote the occurrence of both receptor-positive and -negative clinical breast tumors.

James, Rebecca E.; Lukanova, Annekatrin

2011-01-01

58

Steroids  

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... using illegal steroids. And because all levels of sports — from high school to the pros — are testing athletes for steroid use, there's a growing chance the person will get caught. If caught, he or ... be banned from the sport. But maybe worst of all, any achievements the ...

59

The influence of sex steroids on structural brain maturation in adolescence.  

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Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls. PMID:24416184

Koolschijn, P Cédric M P; Peper, Jiska S; Crone, Eveline A

2014-01-01

60

Longitudinal monitoring of sex steroid hormones in excrement of spectacled eiders (Somateria fischeri).  

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From the 1970s to the 1990s, the breeding population of spectacled eiders (Somateria fischeri) in western Alaska declined by 96%, which led to the listing of this species as threatened under the Endangered Species Act in 1993. Since then, the population has stabilized, but has not recovered to pre-decline numbers. While little is known about reproductive endocrinology in spectacled eiders, in other avian species, estrogen and testosterone are known to initiate and modulate various reproductive processes including yolk protein synthesis, reproductive behaviors and secondary sex characteristics. Measurement of the metabolites of estrogen and testosterone (EM and TM, respectively) in excrement reflect circulating hormone concentrations and provide a non-invasive method to monitor reproductive physiology. We measured concentrations of excreted EM in captive females and TM in males to (1) determine the efficacy of commercially available radioimmunoassay kits to detect EM and TM, (2) describe annual profiles of EM and TM concentrations, and (3) define the reproductive season of captive spectacled eiders using endocrine status. Excrement samples were collected from captive female and male spectacled eiders three times per week throughout 1 year. Female EM and male TM levels were quantified using radioimmunoassay. Mean female EM profile exhibited values exceeding the threshold for "peak" values (EM>193.3 ng/g) from mid-February to early July, and again in September. Additionally, the highest average concentrations of EM were seen in March, May and September. Elevated TM concentrations occurred in mid March, mid May and late June. These data suggest that levels of excreted sex steroids reflect patterns predicted by breeding landmarks in the annual cycle and will assist in field monitoring and captive breeding programs for spectacled eiders. PMID:24406512

Ellsworth, Abigail; Buck, C Loren; Atkinson, Shannon; Hollmén, Tuula

2014-03-01

 
 
 
 
61

Winter profile of plasma sex steroid levels in free-living male western diamond-backed rattlesnakes, Crotalus atrox (Serpentes: Viperidae).  

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Recent field studies on the reproductive ecology of western diamond-backed rattlesnakes (Crotalus atrox) from populations in southern Arizona showed significant differences in the concentration of plasma sex steroids (testosterone, T; 5alpha-dihydrotestosterone, DHT; and 17beta-estradiol, E2) throughout the active season (March-October), and peak levels were coincident with the two mating periods (late summer and early spring). There is, however, no information on levels of sex steroids during winter. Similar to most snakes, hibernating individuals of C. atrox are typically inaccessible, but in southern Arizona, where environmental conditions are typically mild during winter, adult males frequently bask at or near the entrances of communal dens. Basking activity, therefore, offers a unique logistical opportunity to assess the complete annual profile of plasma sex steroid levels in males of a temperate reptile in nature. From November to February, we measured levels of plasma T, DHT, and E2 in adult male C. atrox that were located basking at communal dens. Additionally, cloacal, core body, and ambient air temperatures were obtained to investigate potential relationships between body temperatures and levels of sex steroids. Mean levels of T, DHT, and E2 were relatively high, and the concentration hierarchy was T>DHT>E2. Mean levels of T, DHT, and E2 showed no significant variation across the four months of sampling; however, E2 levels decreased progressively. In the annul cycle, sex steroid levels during winter were not basal when compared to values obtained during the active season. Mean cloacal temperatures of basking males were significantly higher than core body temperatures of non-basking males (inside dens) from November-December, and in February, which suggests that one function of winter basking is to elevate body temperatures. Steroid levels, nonetheless, were not significantly correlated with cloacal temperatures. We suggest that future field studies of male C. atrox should: (a) investigate sex steroid levels in non-basking individuals and (b) test whether elevated levels of sex steroids during winter facilitate the large increases that occur in early spring, which are coincident with the second mating season. Our findings on the reproductive biology of C. atrox and other viperids are discussed in the context of the associated-dissociated model of reproduction. PMID:16828091

Schuett, Gordon W; Repp, Roger A; Taylor, Emily N; DeNardo, Dale F; Earley, Ryan L; Van Kirk, Edward A; Murdoch, William J

2006-10-01

62

Short fused? associations between white matter connections, sex steroids, and aggression across adolescence.  

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Functional neuroimaging studies in adults show that aggression involves reduced brain communication between subcortical and cortical areas dedicated to motivation and control, respectively. Prior research indicates that sex steroid hormone production during adolescence negatively influences the rapid development of white matter connectivity between subcortical and cortical areas during adolescence and may potentiate aggression. Here, we tested this hypothesis in 258 participants between 8 and 25 years of age by using Diffusion Weighted Imaging to examine the microstructure of white matter connections within the fronto-temporal-subcortical network. Trait aggression was measured using the Buss Perry Aggression Questionnaire and testosterone and estradiol levels were measured in saliva. Results indicated that higher levels of testosterone were associated with less white matter integrity within the fronto-temporal-subcortical network (i.e., higher mean diffusivity [MD] longitudinal [LD], and radial diffusivity [RD]). Furthermore, lower fractional anisotropy and higher MD, LD, and RD values within this network increased expressive forms of aggression and reduced inhibited forms of aggression (hostility). Our study indicates higher levels of testosterone relating to lower quality of structural cortical-subcortical connectivity, arguably resulting in a shift from inhibited towards expressive forms of aggression. Our data adds evidence to the idea that aggressive tendencies are subcortically driven, but individuals with relatively high testosterone might have lower structural connectivity within cortical control areas, resulting in a stronger tendency to act on these aggressive tendencies. Hum Brain Mapp 36:1043-1052, 2015. © 2014 Wiley Periodicals, Inc. PMID:25359710

Peper, Jiska S; de Reus, Marcel A; van den Heuvel, Martijn P; Schutter, Dennis J L G

2015-03-01

63

Hippocampal synthesis of sex steroids and corticosteroids: essential for modulation of synaptic plasticity  

Directory of Open Access Journals (Sweden)

Full Text Available Sex steroids play essential roles in the modulation of synaptic plasticity and neuroprotection in the hippocampus. Accumulating evidence shows that hippocampal neurons synthesize both estrogen and androgen. Recently, we also revealed the hippocampal synthesis of corticosteroids. The accurate concentrations of these hippocampus-synthesized steroids are determined by liquid chromatography-tandem mass spectrometry in combination with novel derivatization. The hippocampal levels of 17?-estradiol (E2, testosterone (T, dihydrotestosterone (DHT and corticosterone (CORT, are 5-15 nM, and these levels are sufficient to modulate synaptic plasticity. Hippocampal E2 modulates memory-related synaptic plasticity not only slowly/genomicaly but also rapidly/nongenomically. Slow actions of E2 occur via classical nuclear receptors (ER? or ER?, while rapid E2 actions occur via synapse-localized or extranuclear ER? or ER?. Nanomolar concentrations of E2 changes rapidly the density and morphology of spines in hippocampal neurons. ER?, but not ER?, drives this enhancement/suppression of spinogenesis in adult animals. Nanomolar concentrations of androgens (T and DHT and CORT also increase in the spine density. Kinase networks are involved downstream of ER? and androgen receptor (AR. Newly developed Spiso-3D mathematical analysis is useful to distinguish these complex effects by sex steroids and kinases. Significant advance has been achieved in investigations of rapid modulation by E2 of the long-term depression or the long-term potentiation.

SuguruKawato

2011-10-01

64

Validation of murine and human placental explant cultures for use in sex steroid and phase II conjugation toxicology studies.  

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Human primary placental explant culture is well established for cytokine signaling and toxicity, but has not been validated for steroidogenic or metabolic toxicology. The technique has never been investigated in the mouse. We characterized human and mouse placental explants for up to 96 h in culture. Explant viability (Lactate dehydrogenase) and sex steroid levels were measured in media using spectrophotometry and ELISA, respectively. Expression and activities of the steroidogenic (3?-hydroxysteroid dehydrogenase, Cytochrome P45017A1, Cytochrome P45019), conjugation (UDP-glucuronosyltransferase, sulfotransferase (SULT)), and regeneration (?-glucuronidase, arylsulfatase C (ASC)) enzymes were determined biochemically in tissues with fluorimetric and spectrophotometric assays, and western blot. Explants were viable up to 96 h, but progesterone, estrone, and 17?-estradiol secretion decreased. Steroidogenic enzyme expression and activities were stable in mouse explants and similar to levels in freshly isolated tissues, but were lower in human explants than in fresh tissue (P<0.01). Human and mouse explants exhibited significantly less conjugation after 96 h, SULT was not detected in the mouse, and neither explants had active ASC, although proteins were expressed. Mouse explants may be useful for steroid biochemistry and endocrine disruption studies, but not metabolic conjugation. In contrast, human explants may be useful for studying conjugation for <48 h, but not for steroid/endocrine studies. PMID:25283089

Sato, Brittany L; Ward, Monika A; Astern, Joshua M; Kendal-Wright, Claire E; Collier, Abby C

2015-02-01

65

Sex steroids do not affect muscle weight, oxidative metabolism or cytosolic androgen reception binding of functionally overloaded rat Plantaris muscles  

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The effects of sex steroids on muscle weight and oxidative capacity of rat planaris muscles subjected to functional overload by removal of synergistic muscles were investigated. Ten weeks after bilateral synergist removal, plantaris muscles were significantly hypertrophic compared with unoperated controls. After this period, the ability of the muscles to oxide three substrates of oxidative metabolism was assessed. Experimental procedures are discussed and results are presented herein. Results suggest a lack of beneficial effect of sex hormone status on the process of hypertrophy and on biochemical changes in overloaded muscle. Such findings are not consistent with the idea of synergistic effects of sex steroids and muscle usage.

Max, S. R.; Rance, N.

1983-01-01

66

Interaction of serum sex steroid-binding globulin with cell membranes of human decidual tissue  

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The interaction of the sex steroid-binding globulin (SBG) of human blood with plasma membranes of cells from human decidual tissue - the target tissue of estradiol - was studied. It was shown that SBG in complex with estradiol is capable of interacting specifically with these membranes. The dissociation (K/sub dis/) of this interaction is equal to (3.5 +/- 2.0) 10/sup -12/ M. The interaction of the SBG-estradiol complex with the membranes is characterized by high selectivity: such blood serum globulins as albumin, orosomucoid, transferrin, transcortin, and thyroxine-binding globulin do not compete with SBG for its binding sites on the membranes. The SBG-testosterone complex and SBG without steroid are also incapable of interacting with the membranes.

Avvakumov, G.V.; Survilo, L.I.; Strel' chenok, O.A.

1986-01-20

67

Sex-Dependent Expression of Caveolin 1 in Response to Sex Steroid Hormones Is Closely Associated with Development of Obesity in Rats  

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Caveolin-1 (CAV1) is a conserved group of structural membrane proteins that form special cholesterol and sphingolipid-rich compartments, especially in adipocytes. Recently, it has been reported that CAV1 is an important target protein in sex hormone-dependent regulation of various metabolic pathways, particularly in cancer and diabetes. To clarify distinct roles of CAV1 in sex-dependent obesity development, we investigated the effects of high fat diet (HFD) and sex steroid hormones on CAV1 ex...

Mukherjee, Rajib; Kim, Sang Woo; Choi, Myung Sook; Yun, Jong Won

2014-01-01

68

Impact of androgenic/antiandrogenic compounds (AAC) on human sex steroid metabolizing key enzymes  

International Nuclear Information System (INIS)

Various pesticides, industrial pollutants and synthetic compounds, to which human populations are exposed, are known or suspected to interfere with endogenous sex hormone functions. Such interference potentially affect the development and expression of the male and female reproductive system or both. Chemicals in this class are thus referred to as endocrine disruptors (ED). This emphazises on the relevance of screening ED for a wide range of sex hormone-mimicking effects. These compounds are believed to exert influence on hormonal actions predominantly by (i) interfering with endogenous steroids in that they functionally interact with plasma membrane-located receptors as well as with nuclear receptors both for estrogens and androgens or (ii) affecting the levels of sex hormones as a result of their impact on steroid metabolizing key enzymes. Essential sex hormone-related enzymes within the endocrine system of humans are aromatase, 5?-reductase 2 as well as specific sulfotransferases and sulfatases (so-called phase I and phase II enzymes, respectively). Using suitable human tissues and human cancer cell lines (placenta, prostate, liver and JEG-3, lymph node carcinoma of prostate (LnCaP) cells) we investigated the impact of 10 widely used chemicals suspected of acting as ED with androgenic or antiandrogenic activity (so-called AAC) on the activity of these sex hormone metabolizing key enzymes in humans. In addition, the respective effects of six substances were also stve effects of six substances were also studied as positive controls due to their well-known specific hormonal agonistic/antagonistic activities. The aim of this report and subsequent investigations is to improve human health risk assessment for AAC and other ED

69

Sex steroid levels in urine of cattle of different ages: evaluation of abuse control procedures.  

Science.gov (United States)

Levels of several natural urinary steroids have been determined in the urine of a large number of animals of different cattle categories in the context of steroid abuse in beef production. Bovine animals of different breeds, sex and age included in the Slovene national residue detection plan for steroid abuse were studied. Urine from 120 males and 174 females was analysed. Urinary boldenone, boldione, androstenedione, equiline, medroxyprogesterone, medroxyprogesterone acetate, melengestrol acetate, progesterone, stanozolol, trenbolone, trenbolone acetate, 17?-ethinylestradiol, 17?-methyltestosterone, epitestosterone, 17?-estradiol, testosterone, and nandrolone were determined by LC-MS/MS. Epitestosterone was found in all bulls; while the proportion of animals containing testosterone and androstenedione increased with age. Testosterone was not detected in bulls less than 5 months of age. Epitestosterone levels, however, were not age dependent. The ratio of testosterone to epitestosterone thus increased with age, from 0.13 ± 0.09 at 1-7 months to 0.42 ± 0.10 at 25-38 months. It was significantly (p < 0.01) higher in bulls above 13 months than in younger animals. In contrast to males, no urinary testosterone was found in females, whereas epitestosterone, androstenedione, progesterone and estradiol were present. The proportion of animals of various age groups in which epitestosterone was detected ranged from 68% to 100%, but the differences were not significant. The presence of both estradiol and progesterone in the same sample was not observed in any animal. The results of this study could be helpful in determining physiological urinary steroid levels in order to provide a baseline for the control of steroid abuse in beef production. PMID:24405322

Snoj, Tomaz; Dolenc, Jozica; Kobal, Silvestra

2014-04-01

70

Dendritic spines of the medial amygdala: plasticity, density, shape, and subcellular modulation by sex steroids.  

Science.gov (United States)

The medial nucleus of the amygdala (MeA) is a complex component of the "extended amygdala" in rats. Its posterodorsal subnucleus (MePD) has a remarkable expression of gonadal hormone receptors, is sexually dimorphic or affected by sex steroids, and modulates various social behaviors. Dendritic spines show remarkable changes relevant for synaptic strength and plasticity. Adult males have more spines than females, the density of dendritic spines changes in the course of hours to a few days and is lower in proestrous and estrous phases of the ovarian cycle, or is affected by both sex steroid withdrawal and hormonal replacement therapy in the MePD. Males also have more thin spines than mushroom-like or stubby/wide ones. The presence of dendritic fillopodia and axonal protrusions in the MePD neuropil of adult animals reinforces the evidence for local plasticity. Estrogen affects synaptic and cellular growth and neuroprotection in the MeA by regulating the activity of the cyclic AMP response element-binding protein (CREB)-related gene products, brain-derived neurotrophic factor (BDNF), the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) and the activity-regulated cytoskeleton-related protein (Arc). These effects on signal transduction cascades can also lead to local protein synthesis and/or rearrangement of the cytoskeleton and subsequent numerical/morphological alterations in dendritic spines. Various working hypotheses are raised from these experimental data and reveal the MePD as a relevant region to study the effects of sex steroids in the rat brain. PMID:22763872

Rasia-Filho, Alberto A; Dalpian, Francine; Menezes, Itiana C; Brusco, Janaína; Moreira, Jorge E; Cohen, Rochelle S

2012-08-01

71

The influence of sex steroids on adipose tissue growth and function.  

Science.gov (United States)

Obesity remains a major global health concern. Understanding the metabolic influences of the obesity epidemic in the human population on maintenance of a healthy weight and metabolic profile is still of great significance. The importance and role of white adipose tissue has been long established, particularly with excess adiposity. Brown adipose tissue (BAT), however, has only recently been shown to contribute significantly to the metabolic signature of mammals outside the previously recognised role in small mammals and neonates. BAT's detection in adults has led to a renewed interest and is now considered to be a potential therapeutic target to prevent excess white fat accumulation in obesity, a theory further promoted by the recent discovery of beige fat. Adipose tissue distribution varies significantly between genders. Pre-menopausal females often show enhanced lower and peripheral fat deposition in adiposity deposition compared to the male profile of central and visceral fat accumulation with obesity. This sex disparity is partly attributed to the different effects of sex hormone profiles and interactions on the adipose tissue system. In this review, we explore this intricate relationship and show how modifications in the effects of sex hormones impact on both brown and white adipose tissues. We also discuss the impact of sex hormones on activation of the hypothalamic-pituitary-adrenal (HPA) axis and how the three pathways between adiposity, HPA and sex steroids can have a major contribution to the prevention or maintenance of obesity and therefore on overall health. PMID:25390013

Law, James; Bloor, Ian; Budge, Helen; Symonds, Michael E

2014-07-01

72

Anabolic Steroids  

Science.gov (United States)

... mood swings, fatigue, rest-lessness, loss of appetite, insomnia, reduced sex drive, and steroid cravings, all of ... Abuse Health Effects Chart Tags Fact Sheets Parents Students Teachers Steroids (Anabolic) DrugFacts This page was last ...

73

Racial variation in umbilical cord blood sex steroid hormones and the insulin-like growth factor axis in African-American and white female neonates  

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PURPOSE: To evaluate whether there is racial variation in venous umbilical cord blood concentrations of sex steroid hormones and the insulin-like growth factor (IGF) axis between female African-American and white neonates. METHODS: Maternal and birth characteristics and venous umbilical cord blood samples were collected from 77 African-American and 41 white full-term uncomplicated births at two urban hospitals in 2004 and 2005. Cord blood was measured for testosterone, dehydroespiandroste...

Agurs-collins, Tanya; Rohrmann, Sabine; Sutcliffe, Catherine; Bienstock, Jessica L.; Monsegue, Deborah; Akereyeni, Folasade; Bradwin, Gary; Rifai, Nader; Pollak, Michael N.; Platz, Elizabeth A.

2012-01-01

74

Prognostic factors in recurrent breast cancer: relationships to site of recurrence, disease-free interval, female sex steroid receptors, ploidy and histological malignancy grading.  

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Site of first recurrence, disease-free interval (DFI), female sex steroid receptors, ploidy measurements as well as histological grading have been analysed as potentially valuable predictive factors in 313 cases of recurrent breast cancer. Univariate and multivariate analyses show histological grading, site of recurrence and disease free interval to be useful prognostic variables when assessing prognosis once disease has recurred. High concentrations of oestrogen receptors (ER) were found in ...

Blanco, G.; Holli, K.; Heikkinen, M.; Kallioniemi, O. P.; Taskinen, P.

1990-01-01

75

Steroid Signaling within Drosophila Ovarian Epithelial Cells Sex-Specifically Modulates Early Germ Cell Development and Meiotic Entry  

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Drosophila adult females but not males contain high levels of the steroid hormone ecdysone, however, the roles played by steroid signaling during Drosophila gametogenesis remain poorly understood. Drosophila germ cells in both sexes initially follow a similar pathway. After germline stem cells are established, their daughters form interconnected cysts surrounded by somatic escort (female) or cyst (male) cells and enter meiosis. Subsequently, female cysts acquire a new covering of somatic cell...

Morris, Lucy X.; Spradling, Allan C.

2012-01-01

76

Heat Shock Protein 27 Is Required for Sex Steroid Receptor Trafficking to and Functioning at the Plasma Membrane ?  

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Classical sex steroid receptors (SRs) localize at the plasma membranes (PMs) of cells, initiating signal transduction through kinase cascades that contribute to steroid hormone action. Palmitoylation of the SRs is required for membrane localization and function, but the proteins that facilitate this modification and subsequent receptor trafficking are unknown. Initially using a proteomic approach, we identified that heat shock protein 27 (Hsp27) binds to a motif in estrogen receptor alpha (ER...

Razandi, Mahnaz; Pedram, Ali; Levin, Ellis R.

2010-01-01

77

Epidermal growth factor directs sex-specific steroid signaling through Src activation.  

Science.gov (United States)

Estrogens and androgens exert many biological effects that do not require interactions of their receptors with chromosomal DNA. However, it has been a long-standing question how the sex steroid receptors provoke signal transduction outside the nucleus. Here we have shown that epidermal growth factor (EGF) directs sex-specific steroid signaling through Src activation. We have revealed that estrogen (E2)-induced Src activation takes place in, not only plasma, but also endomembranes. This was found ascribed to the existence of EGF and the occurrence of EGF receptor (EGFR)-involved endocytosis of estrogen receptor together with Src. EGFR, estrogen receptor, and Src were found to form a complex upon E2 stimulation. The cell growth of breast cancer-derived MCF-7 cells was found to remarkably increase through the above EGF-involved estrogen-signaling process. In contrast, the androgen 5alpha-dihydrotestosterone-induced Src activation occurs only in the plasma membrane free from the interaction of EGFR with androgen receptor, irrespective of EGF. The cell growth occurred only moderately as a result. The spatial difference in Src activation between E2 and 5alpha-dihydrotestosterone may be responsible for the different extent of observed cell growth. PMID:17284441

Hitosugi, Taro; Sasaki, Kazuki; Sato, Moritoshi; Suzuki, Yoshiko; Umezawa, Yoshio

2007-04-01

78

Seasonal and sex-related variations in serum steroid hormone levels in wild and farmed brown trout Salmo trutta L. in the north-west of Spain.  

Science.gov (United States)

Serum steroid profiles were investigated in order to evaluate the potential use of circulating sex steroid levels as a tool for sex identification in brown trout. Changes in the serum concentrations of testosterone (T), progesterone (P), 17-?-estradiol (E2), and cortisol (F) in wild and farmed mature female and male brown trout, Salmo trutta L., were measured in each season (January, May, July, and October) in six rivers and four hatcheries located in the north-west of Spain. Serum cortisol levels in farmed brown trout were significantly higher and showed a seasonal pattern opposite to that found in wild trout. Because levels of the hormones under study can be affected by disruptive factors such as exposure to phytoestrogens (which alters the hypothalamic-pituitary-gonadal axis) and infection with Saprolegnia parasitica (which alters the hypothalamic-pituitary-adrenal axis), both factors are taken into account. PMID:24334846

Fregeneda-Grandes, Juan M; Hernández-Navarro, Salvador; Fernandez-Coppel, Ignacio A; Correa-Guimaraes, Adriana; Ruíz-Potosme, Norlan; Navas-Gracia, Luis M; Aller-Gancedo, J Miguel; Martín-Gil, Francisco J; Martín-Gil, Jesús

2013-12-01

79

Sex steroid receptor proteins in foetal, adult and malignant human liver tissue.  

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Sex steroid receptor proteins were studied in human normal liver and hepatocellular carcinoma (HCC). Oestrogen receptor (ER) was detected in nucleosol and cytosol of 4 normal adult and 5 malignant liver specimens and in the cytosol of 6 foetal liver samples. Levels were 27.6-500 fmol mg-1 soluble protein in normal adults (Kd 1.48 X 10(-8) -1.12 X 10(-10) mol 1(-1) ), 45-290 fmol mg-1 in malignant liver tissue (Kd 3.26 X 10(-9) -3.64 X 10(-10) mol 1(-1] and a mean of 93 fmol mg-1 in foetal tis...

Iqbal, M. J.; Wilkinson, M. L.; Johnson, P. J.; Williams, R.

1983-01-01

80

Specific estrogen-binding protein of rat liver and sex steroid metabolism  

International Nuclear Information System (INIS)

Model experiments were conducted to study the effect of a highly purified preparation of specific estrogen-binding protein (SEBP) on the intensity of estradiol and testosterone metabolism under the influence of enzymes in liver homogenate from female rats, not containing SEBP. The liver of mature female rats was homogenized in two volumes of 50 mM Tris-HCl buffer, pH 7.5, containing 600 mg% of glucose. The tritium-steroid was preincubated for 15 min at 0-4 C with 0-4 microg of the preparation of SEBP (200 microl). A standard preparation of partially purified SEBP was obtained from liver cystosol of mature male rats; affinity chromatography on estradiolagarose was used. It is shown that SEBP can really take part in regulation of the dynamics of sex steroids in the liver. E1 did not affect the metabolic rate of H 3-E2 by liver homogenate from females, but caused marked acceleration of H 3-E2 metabolism by male liver homogenate

 
 
 
 
81

Colonic transit in rats: effect of ovariectomy, sex steroid hormones, and pregnancy  

International Nuclear Information System (INIS)

In vitro studies suggest that the female sex steroid hormones [estrogen (E) and progesterone (P)] can affect the myoelectric and mechanical activity of colonic smooth muscle. The present study was designed to examine the influence of the hormones on colonic transit in vivo. Transit was assessed by quantifying the distribution within the colon of a radiolabeled marker (0.5 ?Ci Na251CrO4), using the geometric center method of analysis. Studies were performed with adult male rats and the following groups of female rats: nonpregnant, ovariectomized, ovariectomy plus hormone pretreatment, and pregnant (day 18). Hormone-pretreated animals were studied 24 h following the fourth injection. The data can be summarized as follows. 1) Colonic transit was affected by the timing of the estrus cycle. 2) Ovariectomy eliminated the biphasic transit pattern observed in estruscycling females and resulted in a geometric center value comparable with that of the metestrus-diestrus animals. 3) E + P pretreatment of ovariectomized rats resulted in a significant decrease in the geometric center compared with the untreated ovariectomized rats. 4) The geometric center value in pregnant anials and hormone-pretreated animals. 5) Adult male rats had a geometric center value of 4.12 +/- 0.29. The results suggest that a relation exists between colonic transit and the circulating levels of the steroid hormones

82

Cardiovascular risk factors in men : The role of gonadal steroids and sex hormone-binding globulin  

DEFF Research Database (Denmark)

Males have higher risk of cardiovascular disease (CVD) than premenopausal females. Gonadal steroids are probably involved in the gender difference in CVD, but previous results have been conflicting. We investigated the associations between CVD risk factors and sex hormones in a cross-sectional designed study of 508 healthy males, aged 41 to 72 years. We determined total testosterone (T), sex hormone-binding globulin (SHBG), free androgen index (FAI), and estradiol (E2) and studied their relationship to body fat mass (BF), blood pressure (BP), aortic compliance, left ventricular mass (LVM), and plasma lipids (total cholesterol, high-density lipoprotein [HDL], low-density lipoprotein [LDL], very--low-density lipoprotein [VLDL], and triglycerides). In quartile analyses after adjustment for confounders (age, body mass index [BMI], alcohol consumption, and smoking), SHBG and E2 were positively associated with HDL, while FAI was negatively associated with HDL. T and SHBG were negatively associated with VLDL and triglycerides, while FAI was positively associated with VLDL and triglycerides. T and SHBG were negatively associated with BMI and BF, while FAI and E2 were positively associated with BMI and BF. E2 was negatively associated with LVM. No hormone varied with total cholesterol, LDL, BP, and aortic compliance in the adjusted analyses. In multiple regression analyses, SHBG was the main predictive variable of HDL, VLDL, and triglycerides explaining 12%, 17%, and 17% of the variation, respectively. No other hormones were selected as predictive variables for VLDL and triglycerides, but E2, T, and FAI were selected in the HDL regression, explaining 3%, 2%, and less than 1%, respectively. Our regression analyses illustrate the diverging results when investigating associations between gonadal steroids and lipids with and without SHBG adjustment. Atherogenic lipid profile in males is associated with low SHBG, low T levels, and a high FAI. Males with high E2 levels may have a less atherogenic lipid profile and lower LVM. SHBG is a key hormone in the association between sex hormones and plasma lipids. We suggest that conflicting results of cross-sectional and intervention studies of sex hormones and lipids, in part, may be explained by interindividual differences or changes in SHBG. Thus, further studies on the potential role of SHBG in the development of ischemic heart disease (IHD) should be performed.

Gyllenborg, J; Rasmussen, S L

2001-01-01

83

Signal Transduction Pathway Analysis in Desmoid-type Fibromatosis: TGF?, COX2 and Sex Steroid Receptors  

Science.gov (United States)

Summary Despite reports of sex steroid receptor and COX2 expression in desmoid-type fibromatosis, responses to single agent therapy with anti-estrogens and nonsteroidal anti-inflammatory drugs are unpredictable. Perhaps combination pharmacotherapy might be more effective in desmoid tumors that co-express these targets. Clearly, a further understanding of the signaling pathways deregulated in desmoid tumors is essential for development of targeted molecular therapy. Transforming growth factor-? (TGF?) and bone morphogenetic proteins (BMPs) are important regulators of fibroblast proliferation and matrix deposition, but little is known about the TGF? superfamily in fibromatosis. A tissue microarray representing 27 desmoid tumors was constructed; 14 samples of healing scar and 6 samples of normal fibrous tissue were included for comparison. Expression of selected receptors and activated downstream transcription factors of TGF? family signaling pathways, ?-catenin, sex steroid hormone receptors and COX2 were assessed by immunohistochemistry; patterns of co-expression were explored via correlational statistical analyses. In addition to ?-catenin, immunoreactivity for phosphorylated SMAD2/3 (indicative of active TGF? signaling) and COX2 was significantly increased in desmoid tumors compared to healing scar and quiescent fibrous tissue. Low levels of phosphorylated SMAD1/5/8 were detected in only a minority of cases. TGF? receptor type 1 and androgen receptor were expressed in both desmoid tumors and scar, but not in fibrous tissue. Estrogen receptor-? was present in all cases studied. TGF? signaling appears to be activated in desmoid-type fibromatosis and phosphorylated SMAD2/3 and COX2 immunoreactivity may be of diagnostic utility in these tumors. Given the frequency of androgen receptor, estrogen receptor-? and COX2 co-expression in desmoid tumors, further assessment of the efficacy of combination pharmacotherapy using hormonal agonists/antagonists together with COX2 inhibitors should be considered. PMID:23035734

Mignemi, Nicholas A.; Itani, Doha M.; Fasig, John H.; Keedy, Vicki L.; Hande, Kenneth R.; Whited, Brent W.; Homlar, Kelly C.; Correa, Hernan; Coffin, Cheryl M.; Black, Jennifer O.; Yi, Yajun; Halpern, Jennifer L.; Holt, Ginger E.; Schwartz, Herbert S.; Schoenecker, Jonathan G.; Cates, Justin M. M.

2014-01-01

84

Anabolic Steroids  

Science.gov (United States)

Anabolic steroids are man-made substances related to male sex hormones. Doctors use anabolic steroids to treat some hormone problems in men, delayed ... some diseases. Bodybuilders and athletes often use anabolic steroids to build muscles and improve athletic performance. Using ...

85

Sites of production of sex steroids: secretion of steroids from x-irradiated and polycystic ovaries of rats  

International Nuclear Information System (INIS)

Ovaries of immature rats and PMS-induced pregnant rats were unilaterally x-irradiated. Ten days later, the concentrations of pregnane compounds in the ovarian venous plasma were measured. LH (2 ?g) was injected iv 30 min before bleeding. A comparison of steroid levels in the ovarian venous effluent of rats with and without destruction of selected tissue components by irradiation of the ovaries suggests that the follicles contribute to the secretion of 5?-pregnane-3,20-dione and 3?-hydroxy-5?-pregnan-20-one in the presence of interstitial gland tissue. Because it is known that follicular tissue is involved in the production of estrogens, we studied the interrelationship between the secretion of the two progesterone metabolites and estrogens in follicular polycystic ovaries of androgen-sterilized rats. Normal ovaries of diestrus-2 rats were used as controls for the polycystic ovaries. The injection of LH greatly increased the secretion of 5?-pregnane-3,20-dione and 3?-hydroxy-5?-pregnan-20-one within 1 h in normal ovaries, but the response of polycystic ovaries was low, suggesting low 5?-reductase activity in the cystic ovary. The polycystic ovaries exhibited a marked increase in the secretion of estrogens in response to LH, whereas normal ovaries showed no significant change. These results suggest that low 5?-reductase activity may be causally related to the high level of estrogen secretion in polycystic ovaries of androgen-sterilized ratsrilized rats

86

Selection and use of crystallization inhibitors for matrix-type transdermal drug-delivery systems containing sex steroids.  

Science.gov (United States)

The purpose of this study was to stabilize transdermal drug-delivery systems (TDDS) highly loaded with sex steroids against recrystallization of drugs during storage. To facilitate the selection of potential crystallization inhibitors a drug-excipient interaction test was also established. Analysis of the thermal behaviour of 1:1 steroid-excipient mixtures by differential scanning calorimetry (DSC) revealed that oestradiol and gestodene interact strongly with silicone dioxide and povidones, e.g. povidone K12. The addition of povidone K12 to polyacrylate-based matrix TDDS containing either 3% oestradiol or 2% gestodene resulted in stable systems which did not recrystallize during storage at 25 degrees C for more than 5 years. Significant recrystallization was, on the other hand, observed in non-stabilized reference patches even after 1 to 2 months storage. The DSC screening model proved very effective for selection of inhibitors of the crystallization of sex steroids in matrix TDDS. The crystallization inhibitor approach is a highly versatile stabilization tool for matrix patches containing high concentrations of sex steroids. PMID:10052847

Lipp, R

1998-12-01

87

Steroid signaling within Drosophila ovarian epithelial cells sex-specifically modulates early germ cell development and meiotic entry.  

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Drosophila adult females but not males contain high levels of the steroid hormone ecdysone, however, the roles played by steroid signaling during Drosophila gametogenesis remain poorly understood. Drosophila germ cells in both sexes initially follow a similar pathway. After germline stem cells are established, their daughters form interconnected cysts surrounded by somatic escort (female) or cyst (male) cells and enter meiosis. Subsequently, female cysts acquire a new covering of somatic cells to form follicles. Knocking down expression of the heterodimeric ecdysteroid receptor (EcR/Usp) or the E75 early response gene in escort cells disrupts 16-cell cyst production, meiotic entry and follicle formation. Escort cells lose their squamous morphology and unsheath germ cells. By contrast, disrupting ecdysone signaling in males does not perturb cyst development or ensheathment. Thus, sex-specific steroid signaling is essential for female germ cell development at the time male and female pathways diverge. Our results suggest that steroid signaling plays an important sex-specific role in early germ cell development in Drosophila, a strategy that may be conserved in mammals. PMID:23056242

Morris, Lucy X; Spradling, Allan C

2012-01-01

88

Steroid sex hormone dynamics during estradiol-17? induced gonadal differentiation in Paralichthys olivaceus (Teleostei)  

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Steroid sex hormones, such as estradiol-17? (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichthys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0-G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group ( P>0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P. olivaceus.

Sun, Peng; You, Feng; Liu, Mengxia; Wu, Zhihao; Wen, Aiyun; Li, Jun; Xu, Yongli; Zhang, Peijun

2010-03-01

89

The progestin levonorgestrel disrupts gonadotropin expression and sex steroid levels in pubertal roach (Rutilus rutilus).  

Science.gov (United States)

The aim of the present study was to investigate the effects of the synthetic progestin levonorgestrel (LNG) on the reproductive endocrine system of a teleost fish, the roach (Rutilus rutilus). Pubertal roach were exposed for 28 days in a flow-through system to four concentrations of LNG (3, 31, 312, and 3124 ng/l). Both males and females treated with 3124 ng/l LNG exhibited the upregulated levels of vitellogenin and oestrogen receptor 1 mRNA in the liver. At the same concentration, LNG caused a significant upregulation of the mRNA expression of the gene encoding luteinising hormone ?-subunit (lh?) and the suppression of the mRNA expression of the gene encoding follicle-stimulating hormone ?-subunit (fsh?) in the pituitary of both male and female roach. A lower LNG concentration (312 ng/l) suppressed mRNA expression of fsh? in males only. Females treated with 3124 ng/l LNG exhibited significantly lower plasma 11-ketotestosterone (11-KT) and oestradiol (E2) concentrations, whereas their testosterone (T) level was higher compared with the control. Females exposed to 312 ng/l LNG presented significantly lower plasma E2 concentrations. Males exposed to ?31 ng/l LNG exhibited significantly reduced 11-KT levels. As determined through a histological analysis, the ovaries of females were not affected by LNG exposure, whereas the testes of males exposed to 31 and 312 ng/l LNG exhibited a significantly higher percentage of spermatogonia B compared with the control. The results of the present study demonstrate that LNG disrupts the reproductive system of pubertal roach by affecting the pituitary gonadotropin expression and the sex steroid levels. This disruption was determined to occur in males after exposure to an environmentally relevant concentration (31 ng/l). Moreover, the highest tested concentration of LNG (3124 ng/l) exerted an oestrogenic effect on fish of both sexes. PMID:24893273

Kroupova, H K; Trubiroha, A; Lorenz, C; Contardo-Jara, V; Lutz, I; Grabic, R; Kocour, M; Kloas, W

2014-09-01

90

The studies of controlled release of sex steroids hormones by radiation induced polymerization of glass forming monomers  

International Nuclear Information System (INIS)

The continuous long-term systemic administration of steroid hormones to rats was attempted by the capsules. Glass capsules containing sex hormone were made by low-temperature radiation-induced polymerization. Testosterone was eluted at a constant speed up to the 120th day in vitro, and could be administered up to the 56th day in vivo. The amount of testosterone released in vitro up to the 120th day was only 10% of the content. (Chiba, N.)

91

Influence of the lunar cycle on plasma melatonin, vitellogenin and sex steroids rhythms in Senegal sole, Solea senegalensis  

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The effect of the moon light cycle on plasma melatonin rhythms was examined in Senegal sole (Solea senegalensis) exposed to natural outdoor or artificial indoor lighting conditions. Furthermore, in a second experiment, the effect of the lunar cycle on vitellogenin and sex steroids (Testosterone, T; Estradiol, E2; 11-ketotestosterone, 11kt) was studied using mature individuals during reproductive season. In the first experiment, during full moon, plasma melatonin peaked at night in covered ...

Oliveira, Catarina R.; Duncan, Neil; Pousa?o-ferreira, P.; Man?ano?s, Evaristo L.; Sa?nchez-va?zquez, F. J.

2010-01-01

92

Brain levels of sex steroid hormones in men and women during normal aging and in Alzheimer’s disease  

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We examined the relationships between normal aging, Alzheimer’s disease (AD), and brain levels of sex steroid hormones in men and women. In postmortem brain tissue from neuropathologically normal, postmenopausal women, we found no age-related changes in brain levels of either androgens or estrogens. In comparing women with and without AD at different ages, brain levels of estrogens and androgens were lower in AD cases aged 80 years and older but not significantly different in the 60–79 ye...

Rosario, Emily R.; Chang, Lilly; Head, Elizabeth H.; Stanczyk, Frank Z.; Pike, Christian J.

2011-01-01

93

S100P Expression in response to sex steroids during the implantation window in human endometrium  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background S100P, a protein originally detected in the human placenta, has been found to play an important role in the development and invasion of tumors. Interestingly, we have recently discovered using data mining that S100P was considerably up-regulated during the window of implantation in the human endometrium, but little further information has been available. Methods Real-time PCR and immunofluorescence were performed to examine the expression and location of S100P in the human endometrium and endometrial cells. Estrogen and progesterone were added to the cultured cells to test the response of S100P to sex steroids. Results A dramatic peak, approximately a 100-fold increase in comparison with the proliferative and early- and late-secretory phases, was observed in the endometrium during the mid-secretory phase, which corresponds to the time of embryo implantation. Progesterone regulated the expression of S100P in both primary endometrial epithelial and stromal cells, but estrogen had no significant effect. Conclusions The results indicate that S100P participates in the periodic change of the endometrium under the regulation of progesterone, may be used as a unique biomarker of the receptive endometrium and play an important role in embryo implantation.

Zhang Dan

2012-12-01

94

Postmenopausal serum sex steroids and risk of hormone receptor-positive and -negative breast cancer: a nested case-control study.  

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Prediagnostic endogenous sex steroid hormone levels have well established associations with overall risk of breast cancer. While evidence toward the existence of distinct subtypes of breast cancer accumulates, few studies have investigated the associations of sex steroid hormone levels with risk of hormone receptor [estrogen receptor (ER) and/or progesterone receptor (PR)] defined breast cancer. In a case-control study nested within the EPIC cohort (European Prospective Investigation into Can...

James, RE; Lukanova, A.; Dossus, L.; Becker, S.; Rinaldi, S; Tjønneland, A.; Olsen, A.; Overvad, K.; Mesrine, S.; Engel, P.; Clavel-chapelon, F.; Chang-claude, J.; Vrieling, A.; Boeing, H.; Schu?tze, M.

2011-01-01

95

Endogenous sex steroids in premenopausal women and risk of breast cancer: the ORDET cohort  

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Introduction: Previous studies showed that higher testosterone levels are associated with greater risk of breast cancer in premenopausal women, but the literature is scant and inconsistent. Methods: In a prospective nested case-control study of 104 premenopausal women with incident breast cancer and 225 matched controls, all characterized by regular menstrual cycles throughout their lifetime, we measured the concentration of estradiol, total and free testosterone (FT), progesterone, sex hormo...

Schernhammer, Eva S.; Sperati, Francesca; Razavi, Pedram; Agnoli, Claudia; Sieri, Sabina; Berrino, Franco; Krogh, Vittorio; Abbagnato, Carlo Alberto; Grioni, Sara; Blandino, Giovanni; Schunemann, Holger J.; Muti, Paola

2013-01-01

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Testosterone regulation of sex steroid-related mRNAs and dopamine-related mRNAs in adolescent male rat substantia nigra  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Increased risk of schizophrenia in adolescent males indicates that a link between the development of dopamine-related psychopathology and testosterone-driven brain changes may exist. However, contradictions as to whether testosterone increases or decreases dopamine neurotransmission are found and most studies address this in adult animals. Testosterone-dependent actions in neurons are direct via activation of androgen receptors (AR or indirect by conversion to 17?-estradiol and activation of estrogen receptors (ER. How midbrain dopamine neurons respond to sex steroids depends on the presence of sex steroid receptor(s and the level of steroid conversion enzymes (aromatase and 5?-reductase. We investigated whether gonadectomy and sex steroid replacement could influence dopamine levels by changing tyrosine hydroxylase (TH protein and mRNA and/or dopamine breakdown enzyme mRNA levels [catechol-O-methyl transferase (COMT and monoamine oxygenase (MAO A and B] in the adolescent male rat substantia nigra. We hypothesized that adolescent testosterone would regulate sex steroid signaling through regulation of ER and AR mRNAs and through modulation of aromatase and 5?-reductase mRNA levels. Results We find ER? and AR in midbrain dopamine neurons in adolescent male rats, indicating that dopamine neurons are poised to respond to circulating sex steroids. We report that androgens (T and DHT increase TH protein and increase COMT, MAOA and MAOB mRNAs in the adolescent male rat substantia nigra. We report that all three sex steroids increase AR mRNA. Differential action on ER pathways, with ER? mRNA down-regulation and ER? mRNA up-regulation by testosterone was found. 5? reductase-1 mRNA was increased by AR activation, and aromatase mRNA was decreased by gonadectomy. Conclusions We conclude that increased testosterone at adolescence can shift the balance of sex steroid signaling to favor androgenic responses through promoting conversion of T to DHT and increasing AR mRNA. Further, testosterone may increase local dopamine synthesis and metabolism, thereby changing dopamine regulation within the substantia nigra. We show that testosterone action through both AR and ERs modulates synthesis of sex steroid receptor by altering AR and ER mRNA levels in normal adolescent male substantia nigra. Increased sex steroids in the brain at adolescence may alter substantia nigra dopamine pathways, increasing vulnerability for the development of psychopathology.

Purves-Tyson Tertia D

2012-08-01

97

Heat shock protein 27 is required for sex steroid receptor trafficking to and functioning at the plasma membrane.  

Science.gov (United States)

Classical sex steroid receptors (SRs) localize at the plasma membranes (PMs) of cells, initiating signal transduction through kinase cascades that contribute to steroid hormone action. Palmitoylation of the SRs is required for membrane localization and function, but the proteins that facilitate this modification and subsequent receptor trafficking are unknown. Initially using a proteomic approach, we identified that heat shock protein 27 (Hsp27) binds to a motif in estrogen receptor alpha (ERalpha) and promotes palmitoylation of the SR. Hsp27-induced acylation occurred on the ERalpha monomer and augmented caveolin-1 interactions with ERalpha, resulting in membrane localization, kinase activation, and DNA synthesis in breast cancer cells. Oligomerization of Hsp27 was required, and similar results were found for the trafficking of endogenous progesterone and androgen receptors to the PMs of breast and prostate cancer cells, respectively. Small interfering RNA (siRNA) knockdown of Hsp27 prevented sex SR trafficking to and signaling from the membrane. These results identify a conserved and novel function for Hsp27 with potential as a target for interrupting signaling from membrane sex SRs to tumor biology in hormone-responsive cancers. PMID:20439495

Razandi, Mahnaz; Pedram, Ali; Levin, Ellis R

2010-07-01

98

Adults with Prader-Willi Syndrome have Weaker Bones: Effect of Treatment with GH and Sex Steroids.  

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Obesity has been considered to have a protective effect against the risk of fractures in adults. However, a high frequency of fracture is described in obese adults with Prader-Willi syndrome. To evaluate bone geometry, density and strength in a group of adult obese patients with Prader-Willi syndrome (PWS) and to examine the modulating effect on bone of treatment with growth hormone (GH) and sex steroids. This was a cross-sectional study performed in 41 (17 males, 24 females) obese subjects with genetically confirmed PWS, aged 29.4 ± 8.6 years. Forty-six healthy subjects (22 males and 24 females) served as controls. Digitalized X-rays were evaluated at the level of the 2nd metacarpal bone to assess bone geometry, i.e. cross-sectional area (CSA), cortical area (CA), medullary area (MA), metacarpal index (MI) and bone strength evaluated as bending breaking resistance index (BBRI). DEXA was also used to evaluate body composition and bone mineral density (total body, lumbar spine and femoral neck). PWS subjects, after adjusting for height and bone size, had a reduced CSA, CA and BBRI, while bone density was not different. GH treatment had a positive effect and sex steroids a negative effect on bone size and strength. PWS subjects showed a reduced bone size at the metacarpus leading to a reduced strength, while bone density was appropriate for size. GH treatment improves bone geometry but not bone density. Bone strength was significantly reduced in PWS patients who did not receive GH and had been treated with sex steroids. PMID:25577526

Longhi, Silvia; Grugni, Graziano; Gatti, Davide; Spinozzi, Emiliano; Sartorio, Alessandro; Adami, Silvano; Fanolla, Antonio; Radetti, Giorgio

2015-02-01

99

The association of smoking with clinical indicators of altered sex steroids--a study of 50,145 women.  

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This study was designed to test the association of smoking with four clinically apparent conditions that may be related to altered sex steroids: natural and induced menopause, infertility, oligomenorrhea, and hirsutism. Data were obtained from the personal inventories of 50,145 women ages 20-59 years in TOPS, a weight reduction program. The age-adjusted odds ratios of each condition for heavy smokers compared with nonsmokers were 1.59 for natural menopause, 1.49 for induced menopause, 1.35 fo...

Hartz, A. J.; Kelber, S.; Borkowf, H.; Wild, R.; Gillis, B. L.; Rimm, A. A.

1987-01-01

100

Organization of Cytochrome P450 Enzymes Involved in Sex Steroid Synthesis: PROTEIN-PROTEIN INTERACTIONS IN LIPID MEMBRANES*  

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Mounting evidence underscores the importance of protein-protein interactions in the functional regulation of drug-metabolizing P450s, but few studies have been conducted in membrane environments, and none have examined P450s catalyzing sex steroid synthesis. Here we report specific protein-protein interactions for full-length, human, wild type steroidogenic cytochrome P450 (P450, CYP) enzymes: 17?-hydroxylase/17,20-lyase (P450c17, CYP17) and aromatase (P450arom, CYP19), as well as their elec...

Praporski, Slavica; Ng, Su May; Nguyen, Ann D.; Corbin, C. Jo; Mechler, Adam; Zheng, Jie; Conley, Alan J.; Martin, Lisandra L.

2009-01-01

 
 
 
 
101

Sjögren's syndome and extragonadal sex steroid formation: a clue to a better disease control?  

Science.gov (United States)

Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphoplasmacytoid focal adenitis leading to mucosal dryness, with 9:1 female dominance and peak incidence at menopause. Due to autoimmune adenitis it can be speculated that the normal epithelial cell renewal has failed, possibly as a result of local intracrine failure to process dehydroepiandrosterone (DHEA) to dihydrotestosterone (DHT). Local intracrine/-cellular DHT deficiency seems to predispose to SS if estrogens are low, in menopausal women and in men. This intracrine failure could be the initial noxious stimulus, factor X, initiating the development of SS. Abnormal release and presentation of exocrine gland-derived antigens (Ag-epitopes), in a complex with major histocompatibility complex class II (MHC II), by migratory dendritic cells (DC) activates T-cells in the regional lymph nodes. B-cells with the same specificity capture and present self-Ag to Th-cells which provide T-cell help. B-cells transform to plasma cells and start to produce autoantibodies (Ab) against these T-cell-dependent Ag. Ab against SS-A/Ro and SS-B/La ribonucleoproteins occur only in HLA-DQw2.1/DQw6 heterozygous individuals, but hY-RNA and RNA polymerase III transcripts in these Ag may in all SS patients stimulate toll-like receptors (TLR) 7 and 9 of the plasmacytoid DCs, because IFN-? and IFN-signature are produced. CD8+?E?7+cytotoxic T-cells activated via cross-presentation recirculate to attack intracrine-deficient, apoptotic epithelial cells expressing self-Ag on their surface. Exocrine glands fall into the sphere of mucosal/gut-associated lymphatic tissue. This together with immune complexes spreads the immunological memory/aggression to extra-glandular sites explaining the systemic nature of the syndrome. Secondary SS could be explained by disturbed lymphocyte recirculation. There is no conclusive evidence that SS in those few men affected is more severe than in women, suggesting that sex steroid endo-/intracrinology has its major impact on the target tissue, not on immune modulation. This article is part of a Special Issue entitled 'Essential role of DHEA'. PMID:25158020

Konttinen, Y T; Stegajev, V; Al-Samadi, A; Porola, P; Hietanen, J; Ainola, M

2015-01-01

102

Correlation of sex steroid and gonadotropin levels with body mass index in underweight and overweight female patients.  

Science.gov (United States)

Both extreme underweight or overweight negatively affects reproductive health, but evidence is inconsistent in terms of mechanisms by which low or high BMI causes reproductive problems. The aim of our study was to investigate associations of sex steroids and gonadotropins with BMI in underweight and overweight patients since childhood. In this study 48 underweight and 55 overweight/obese females underwent full clinical-hormonal analyses. Polycystic ovarian syndrome and metabolic syndrome was the most frequent in overweight and obese patients, whilst non-classical congenital adrenal hyperplasia and ovarian dysfunction prevailed in underweight patients (P=.000). FSH (P=.013) and SHBG (P=.000) levels were higher in patients with low BMI, whilst FT (p=.019) and TT (p=.003) levels were higher in high BMI patients. No difference was found in terms of AMH (P>.05). BMI negatively correlated with FSH (P=.009) and SHBG (P=.001) and positively correlated with FT (P=.001) and TT (P=.002). So sex steroid and gonadotropin levels are determined by particular reproductive disorders, which are associated to childhood BMI and progression of BMI changes. PMID:25541818

Chikvaidze, N; Khristesashvili, J; Gegechkori, M

2014-11-01

103

Sex steroid-independent effects of photostimulation on the song-control system of white-throated sparrows (Zonotrichia albicollis).  

Science.gov (United States)

Brain nuclei within the song-control system of songbirds are seasonally plastic during adulthood. These nuclei are larger in birds exposed to long, spring-like days than short, winter-like days. There is overwhelming evidence that this effect is mediated by testosterone (T). However, castration studies have also demonstrated that photostimulation has gonad-independent effects on song-control system plasticity, but these studies rarely control for extra-gonadal sources of T. In this study, we used anti-androgen and anti-estrogen treatments in combination with castration to determine the sex steroid-independent effects of photostimulation on HVC size and doublecortin immunoreactivity in white-throated sparrows (Zonotrichia albicollis). Birds were kept on short days or photostimulated for 1 month. Photostimulated birds were intact, castrated and treated with anti-androgens and anti-estrogens, or castrated and treated with T. HVC volumes of photostimulated birds were significantly larger than short-day birds. HVC volume of castrated birds given anti-androgens/-estrogens was significantly larger than short-day birds, indicating a sex steroid-independent effect of photostimulation. Similar results were observed for RA. The number of migrating neurons (immunoreactive for doublecortin) in HVC did not differ between treatment groups. Our data support the view that photostimulation alone can drive song-control system nuclei growth, and that concurrent exposure to T potentiates this growth. Moreover, these effects do not appear dependent on modulation of neuron migration. PMID:24818971

Robertson, Brian D; Hasstedt, Michael R; Vandermeer, Caitlin L; MacDougall-Shackleton, Scott A

2014-08-01

104

A possible relationship between Takotsubo cardiomyopathy and female sex steroid-related modulation of functional cerebral asymmetry.  

Science.gov (United States)

Takotsubo cardiomyopathy (Tc) is a transient left ventricular apical ballooning syndrome, with symptoms and signs of acute myocardial infarction. Tc syndrome, which occurs predominantly in postmenopausal women, is characterized by increase of sympathetic activity. Studies on the gender-specific differences in sympatho-vagal regulation and functional cerebral asymmetry (FCA) imply that female pattern of dominance is characterized by the left hemisphere, which is believed to have parasympathetic predominance, whereas male pattern indicates dominance of the right hemisphere, which is believed to have sympathetic predominance. Fluctuating levels of female sex steroids are supposed to change FCA, modulating transcallosal inter-hemispheric inhibition across the menstrual cycle. The findings suggest that FCA is enhanced during the low steroid phase (menstrual phase), whereas, during high estrogen and/or progesterone phases (follicular and luteal phase) FCA is reduced. This theory is in line with concept of decreased magnitude of inter-hemispheric cortical lateralization in premenopausal women compared to men and postmenopausal women. Therefore, if postmenopausal women are more lateralized for a variety of cerebral functions, they have less balanced equilibrium between the right-sided sympathetic and left-sided parasympathetic predominance. Decrease of endogenous female sex steroid levels in postmenopausal women leads to reduced influence of estrogens to the left hemisphere, which is believed to have parasympathetic predominance. If both of these mechanisms result in sympatho-vagal imbalance, increasing sympathetic system activity in postmenopausal women, it seems reasonable why postmenopausal women became more susceptible to sympathetically-mediated syndromes such as Takotsubo cardiomyopathy. PMID:25618443

Dra?a, S

2015-03-01

105

Social modulation of sex steroid concentrations in the urine of male cichlid fish Oreochromis mossambicus  

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The relationship between urinary concentrations (free + sulfates + glucuronides) of the steroids testosterone (T), 11-ketotestosterone (11KT), 17?, 20ß-dihydroxy-4-preg- nen-3-one (17,20ß-P) and 17a,20a-dihydroxy-4-preg- nen-3-one (17,20?-P), and the social behavior of males of the cichlid ?sh Oreochromis mossambicus was inves- tigated. After 8 days of isolation none of the steroids were good predictors of social dominance developed after subsequent formation of ...

Oliveira, R. F.; Almada, V. C.; Canario, Adelino V. M.

1996-01-01

106

Targeting rapid action of sex-steroid receptors in breast and prostate cancers.  

Science.gov (United States)

Human breast and prostate cancers are complex diseases caused by the progressive accumulation of gene mutations combined with epigenetic deregulation of critical genes and derangement of signaling pathways. Compelling evidence indicates that steroid hormones elicit non-genomic responses in cytoplasm of target cells. In this cellular location, steroid-coupled receptors recruit signaling effectors or scaffold proteins, thereafter activating multiple pathways leading to proliferation, survival, migration and invasiveness. Thus, the immediate challenge is the dissection of key upstream events regulating steroid response in target tissues to prevent progression and improve treatment of breast and prostate cancers. Progress in our understanding of the molecular mechanisms that play a master role in these cancers has strongly stimulated the search for specific inhibitors of key signaling molecules. This review aims to give an up-to-date report of the complex network regulating non-genomic action of steroid hormones in target cells. The final section highlights recent advances from our laboratory and future directions in alternative approaches for the treatment of breast and prostate cancers. PMID:22201885

Giovannelli, Pia; Di Donato, Marzia; Giraldi, Tiziana; Migliaccio, Antimo; Castoria, Gabriella; Auricchio, Ferdinando

2012-01-01

107

Targeting rapid action of sex steroid receptors in breast and prostate cancers.  

Science.gov (United States)

Human breast and prostate cancers are complex diseases caused by the progressive accumulation of gene mutations combined with epigenetic deregulation of critical genes and derangement of signaling pathways. Compelling evidence indicates that steroid hormones elicit non-genomic responses in cytoplasm of target cells. In this cellular location, steroid-coupled receptors recruit signaling effectors or scaffold proteins, thereafter activating multiple pathways leading to proliferation, survival, migration and invasiveness. Thus, the immediate challenge is the dissection of key upstream events regulating steroid response in target tissues to prevent progression and improve treatment of breast and prostate cancers. Progress in our understanding of the molecular mechanisms that play a master role in these cancers has strongly stimulated the search for specific inhibitors of key signaling molecules. This review aims to give an up-to-date report of the complex network regulating non-genomic action of steroid hormones in target cells. The final section highlights recent advances from our laboratory and future directions in alternative approaches for the treatment of breast and prostate cancers. PMID:21622172

Giovannelli, Pia; Di Donato, Marzia; Giraldi, Tiziana; Migliaccio, Antimo; Castoria, Gabriella; Auricchio, Ferdinando

2011-01-01

108

Steroid measurement with LC-MS/MS. Application examples in pediatrics.  

Science.gov (United States)

The correct measurement of steroids is vital for the diagnosis of congenital adrenal hyperplasia (CAH), apparent mineralocorticoid excess, familial hyperaldosteronism type I, primary aldosteronism, Cushing's disease, adrenal insufficiency, etc. Steroid diagnostics also plays an important role in disorders of sexual differentiation and gonadal function. Steroid metabolism is involved in evaluations for precocious puberty, premature thelarche, and polycystic-ovary disease. Finally, the hypothalamo-pituitary-adrenal (HPA) axis is considered to be one of the major systems involved in fetal programming or in stress regulation. Most methods for the determination of steroid hormones are based on immunoassays, which are rapid and easy to perform. However, the reliability of several steroid immunoassays has been shown to be questionable because of the lack of specificity and of matrix effects. Immunological methods, especially direct assays, often overestimate true steroid values. Patient follow-up over time or between laboratories, as well as longitudinal studies, are therefore extremely difficult. This is of particular importance in pediatrics. Liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) is an increasingly common tool in the clinical laboratory and has the potential to overcome the limitations of immunoassays. LC-MS/MS affords the specificity, imprecision, and limits of quantification necessary for the reliable measurement of steroids, expanding diagnostic capabilities. In addition to the high throughput, the method requires minimal sample preparation and a small sample volume. All these features make it an attractive method to use in a clinical setting. Moreover, LC-MS/MS has the advantage that a spectrum of steroid hormones can be measured simultaneously. Steroid profiling is a very effective method for distinguishing almost all steroid-related disorders. It allows accurate diagnosis and is very useful in many clinical situations. Steroid profiles open up new vistas. The applicability for clinical samples and questions in pediatric endocrinology will be discussed. PMID:20036331

Rauh, Manfred

2010-08-01

109

Parasitic castration, growth, and sex steroids in the freshwater bonefish Cyphocharax gilbert (Curimatidae) infested by Riggia paranensis (Cymothoidea)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Cyphocharax gilbert exibe castração parasitária quando está infestado pelo crustáceo Riggia paranensis, estando impossibilitado de reproduzir. Os peixes foram coletados no trecho médio do rio Itabapoana, Brasil, para analisar a prevalência do parasitismo, quantificar crescimento e as concentrações d [...] e esteróides sexuais, considerando o tamanho do corpo, o sexo e a condição reprodutiva dos espécimes. A maioria dos peixes analisados estava infestada (56,0%). A presença de duas linhas em escamas foi mais freqüente entre os peixes infestados (22,0%) que entre os peixes não infestados (12,0% para as fêmeas e 10,0% para os machos). A presença de três linhas na escama foi rara (3,5% entre os peixes infestados e 2,0% entre as fêmeas não infestadas). Estes resultados sugerem que o crescimento no hospeideiro pode ser mais rapido que no peixes não parasitados. As concentrações de esteróides sexuais no soro dos peixes não infestados variaram entre os diferentes estágios reprodutivos (17 beta-estradiol: 60,0 a 976,7 pg/ml; total testosterona: 220,0 a 3.887,7 pg/ml). Todos os peixes infestados apresentaram baixos níveis dos dois hormônios esteroidais e ausência de desenvolvimento gonadal. Os níveis de esteróides sexuais nas fêmeas infestadas foram próximos aos níveis encontrados nas fêmeas pós-desovadas. A concentração de testosterona encontrada nos machos infestados foi inferior àquela obtida nos machos que estavam iniciando o desenvolvimento gonadal. Estes resultados sugerem que R. paranensis impede a reprodução de C. gilbert, afetando o sistema endócrino do hospedeiro. Abstract in english Cyphocharax gilbert shows parasitic castration when infested by the crustacean Riggia paranensis, being unable to reproduce. Fish were sampled in the middle rio Itabapoana, Brazil, to study the prevalence of parasitism, growth, and sex steroid concentrations, considering the body size, sex, and repr [...] oductive condition of specimens. Most of the fish analyzed were infested (56.0%). The presence of two lines on the scales was more frequent among infested fish (22.0%) than among fish without parasites (12.0% for females and 10.0% for males). The occurrence of three lines on the scales was rare (3.5% among infested and 2.0% among females without parasites). These results suggest that growth of the host is faster than that of non infested fish. The serum concentrations of sex steroids from fish without parasites varied at different gonadal development stages (17 beta-estradiol: 60.0 to 976.7 pg/ml; total testosterone: 220.0 to 3,887.7 pg/ml). All infested fish had lower levels of the two sex steroids and undeveloped gonads. Sex steroids levels in infested females were close to those in females at post-spawning stages. Total testosterone concentrations of infested males were below those of males at early gonadal maturation stage. These results suggest that R. paranensis reduces the reproductive capacity of C. gilbert by affecting the host endocrine system.

Neuza R. W., Lima; Juliana de S., Azevedo; Leonardo G. da, Silva; Marilvia, Dansa-Petretski.

2007-12-01

110

Parasitic castration, growth, and sex steroids in the freshwater bonefish Cyphocharax gilbert (Curimatidae infested by Riggia paranensis (Cymothoidea  

Directory of Open Access Journals (Sweden)

Full Text Available Cyphocharax gilbert shows parasitic castration when infested by the crustacean Riggia paranensis, being unable to reproduce. Fish were sampled in the middle rio Itabapoana, Brazil, to study the prevalence of parasitism, growth, and sex steroid concentrations, considering the body size, sex, and reproductive condition of specimens. Most of the fish analyzed were infested (56.0%. The presence of two lines on the scales was more frequent among infested fish (22.0% than among fish without parasites (12.0% for females and 10.0% for males. The occurrence of three lines on the scales was rare (3.5% among infested and 2.0% among females without parasites. These results suggest that growth of the host is faster than that of non infested fish. The serum concentrations of sex steroids from fish without parasites varied at different gonadal development stages (17 beta-estradiol: 60.0 to 976.7 pg/ml; total testosterone: 220.0 to 3,887.7 pg/ml. All infested fish had lower levels of the two sex steroids and undeveloped gonads. Sex steroids levels in infested females were close to those in females at post-spawning stages. Total testosterone concentrations of infested males were below those of males at early gonadal maturation stage. These results suggest that R. paranensis reduces the reproductive capacity of C. gilbert by affecting the host endocrine system.Cyphocharax gilbert exibe castração parasitária quando está infestado pelo crustáceo Riggia paranensis, estando impossibilitado de reproduzir. Os peixes foram coletados no trecho médio do rio Itabapoana, Brasil, para analisar a prevalência do parasitismo, quantificar crescimento e as concentrações de esteróides sexuais, considerando o tamanho do corpo, o sexo e a condição reprodutiva dos espécimes. A maioria dos peixes analisados estava infestada (56,0%. A presença de duas linhas em escamas foi mais freqüente entre os peixes infestados (22,0% que entre os peixes não infestados (12,0% para as fêmeas e 10,0% para os machos. A presença de três linhas na escama foi rara (3,5% entre os peixes infestados e 2,0% entre as fêmeas não infestadas. Estes resultados sugerem que o crescimento no hospeideiro pode ser mais rapido que no peixes não parasitados. As concentrações de esteróides sexuais no soro dos peixes não infestados variaram entre os diferentes estágios reprodutivos (17 beta-estradiol: 60,0 a 976,7 pg/ml; total testosterona: 220,0 a 3.887,7 pg/ml. Todos os peixes infestados apresentaram baixos níveis dos dois hormônios esteroidais e ausência de desenvolvimento gonadal. Os níveis de esteróides sexuais nas fêmeas infestadas foram próximos aos níveis encontrados nas fêmeas pós-desovadas. A concentração de testosterona encontrada nos machos infestados foi inferior àquela obtida nos machos que estavam iniciando o desenvolvimento gonadal. Estes resultados sugerem que R. paranensis impede a reprodução de C. gilbert, afetando o sistema endócrino do hospedeiro.

Neuza R. W. Lima

2007-12-01

111

Serum pituitary and sex steroid hormone levels in the etiology of prostatic cancer--a population-based case-control study.  

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The hypothesis that serum concentrations of pituitary hormones, sex steroid hormones, or sex hormone-binding globulin (SHBG) affect the occurrence of prostatic cancer was tested in a consecutive sample of 93 patients with newly diagnosed, untreated cancer and in 98 population controls of similar ages without the disease. Cases did not differ significantly from controls regarding serum levels of luteinising hormone (LH) or follicle stimulating hormone (FSH). Remarkably close agreement was foun...

Andersson, S. O.; Adami, H. O.; Bergstro?m, R.; Wide, L.

1993-01-01

112

Regional Difference in Sex Steroid Action on Formation of Morphological Sex Differences in the Anteroventral Periventricular Nucleus and Principal Nucleus of the Bed Nucleus of the Stria Terminalis  

Science.gov (United States)

Sex steroid action is critical to form sexually dimorphic nuclei, although it is not fully understood. We previously reported that masculinization of the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), which is larger and has more neurons in males than in females, involves aromatized testosterone that acts via estrogen receptor-? (ER?), but not estrogen receptor-? (ER?). Here, we examined sex steroid action on the formation of the anteroventral periventricular nucleus (AVPV) that is larger and has more neurons in females. Morphometrical analysis of transgenic mice lacking aromatase, ER?, or ER? genes revealed that the volume and neuron number of the male AVPV were significantly increased by deletion of aromatase and ER? genes, but not the ER? gene. We further examined the AVPV and BNSTp of androgen receptor knockout (ARKO) mice. The volume and neuron number of the male BNSTp were smaller in ARKO mice than those in wild-type mice, while no significant effect of ARKO was found on the AVPV and female BNSTp. We also examined aromatase, ER?, and AR mRNA levels in the AVPV and BNSTp of wild-type and ARKO mice on embryonic day (ED) 18 and postnatal day (PD) 4. AR mRNA in the BNSTp and AVPV of wild-type mice was not expressed on ED18 and emerged on PD4. In the AVPV, the aromatase mRNA level was higher on ED18, although the ER? mRNA level was higher on PD4 without any effect of AR gene deletion. Aromatase and ER? mRNA levels in the male BNSTp were significantly increased on PD4 by AR gene deletion. These results suggest that estradiol signaling via ER? during the perinatal period and testosterone signaling via AR during the postnatal period are required for masculinization of the BNSTp, whereas the former is sufficient to defeminize the AVPV. PMID:25398007

Kanaya, Moeko; Tsuda, Mumeko C.; Sagoshi, Shoko; Nagata, Kazuyo; Morimoto, Chihiro; Tha Thu, Chaw Kyi; Toda, Katsumi; Kato, Shigeaki; Ogawa, Sonoko; Tsukahara, Shinji

2014-01-01

113

Influx of testosterone-binding globulin (TeBG) and TeBG-bound sex steroid hormones into rat testis and prostate  

Energy Technology Data Exchange (ETDEWEB)

The availability of testosterone and estradiol to Sertoli and prostate cells is dependent upon 1) the permeability properties of the blood-tubular barrier (BTB) of the testis or prostate cell membrane, and 2) sex steroid binding to plasma proteins, such as albumin or testosterone-binding globulin (TeBG). Sex steroid influx into these tissues was studied after in vivo arterial bolus injections of (/sup 3/H)testosterone or (/sup 3/H)estradiol in anesthetized rats. Both testosterone and estradiol were readily cleared across the BTB or prostate cell membrane in the absence of plasma proteins and in the presence of human pregnancy serum, in which testosterone or estradiol are 80-95% distributed to TeBG. The extravascular extraction of (/sup 3/H)TeBG across the BTB or prostate plasma membrane (73 +/- 2% (+/- SE) and 92 +/- 9%, respectively) was significantly greater than extraction of (/sup 3/H)albumin or other plasma space markers and indicative of a rapid first pass clearance of TeBG by Sertoli or prostate cells. In summary, these studies indicate that 1) testosterone and estradiol are readily cleared by Sertoli and prostate cells; 2) albumin- and TeBG-bound sex steroids represent the major circulating pool of bioavailable hormone for testis or prostate; and 3) the TeBG-sex steroid complex may be nearly completely available for influx through the BTB or prostate plasma membrane.

Sakiyama, R.; Pardridge, W.M.; Musto, N.A.

1988-07-01

114

Influence of mesonephros on foetal and neonatal rabbit gonads. I. Sex-steroid release by the testis in vitro  

DEFF Research Database (Denmark)

The experiments were performed to study the influence of mesonephros on gonadal sex hormone release. Foetal and neonatal rabbit testes were cultured for 5 days, with and without their mesonephric tissue. The culture media were harvested every day and analyzed by RIA for the content of testosterone, progesterone and oestradiol. The development of the tissues were evaluated microscopically after culturing. The results show that between day 20 pc and day 1 pp the mesonephric tissue lowered the amounts of testosterone in co-cultures with testis. This effect disappears when the mesonephric derived cells develop the capacity to synthesize a meiosis inducing substance (MIS). A relationship between decrease of testosterone and secretion of MIS is discussed. It is concluded that the steroid producing cells of the testis, the Leydig cells, originate or are heavily influenced by mesonephros during early testicular organogenesis.

Grinsted, Jacob Peter; Byskov, A G

1982-01-01

115

Sexual activity and plasma levels of sex steroids in the aspic viper Vipera aspis L. (Reptilia, Viperidae).  

Science.gov (United States)

Reproductive behavior and associated sexual activity was studied in individual male and female Vipera aspis over a 3-year period in western France in an attempt to correlate mating behavior with blood levels of gonadal sex steroids. Males had higher average levels of both testosterone (T) and 5 alpha-dihydrotestosterone (DHT) than females. Levels of progesterone (P) did not differ significantly between the two sexes but estradiol-17 beta (E2) concentrations were significantly higher in females during the season of mating. Spring mating behavior and copulation in males was associated with significantly increased levels of T and DHT, compared with postmating males; and a similar, but not significant trend, was evident with autumnal mating. The only statistically significant hormonal difference detected in males showing no sexual activity in autumn, was an elevated level of E2 at 0.52 +/- 0.20 ng/ml compared with 0.09 +/- 0.03 ng/ml in spring-breeding males (P = 0.05). Estrus in females is associated with increased levels of all four steroids but significant only for E2 and DHT. Levels of P were significantly reduced in females displaying seasonal anestrous in the spring immediately following reproduction. Females not displaying estrus in either spring or autumn had significantly lower plasma DHT and E2. Although mating behavior in males is associated statistically with elevated levels of T and DHT, a tight correlation is not obvious at the individual level, suggesting that increased concentrations of androgens are a necessary, but not sufficient, condition for mating. The data from V. aspis suggest that, as in a number of other reptilian species, high circulating levels of androgens function to "condition" or "organize" sexual behavior in males which may be displayed at some later time, well after actual levels have fallen, thus engendering the impression that reproductive behavior may be temporally dissociated from essential hormonal stimuli. PMID:8224772

Saint Girons, H; Bradshaw, S D; Bradshaw, F J

1993-09-01

116

The macrophage low-grade inflammation marker sCD163 is modulated by exogenous sex steroids  

DEFF Research Database (Denmark)

Soluble CD163 (sCD163) is a novel marker linked to states of low grade inflammation such as diabetes, obesity, liver disease and atherosclerosis, all prevalent in subjects with Turner and Klinefelter Syndromes. We aimed to assess the levels of sCD163 and the regulation of sCD163 in regards to treatment with sex hormone therapy in males with and without Klinefelter Syndrome and females with and without Turner Syndrome. Males with Klinefelter Syndrome (n=70) and age-matched controls (n=71) participating in a cross-sectional study and 12 healthy males from an experimental hypogonadism study. Females with Turner Syndrome (n=8) and healthy age- matched controls (n=8) participating in a randomized cross-over trial. The intervention comprised of treatment with sex steroids. Males with Klinefelter Syndrome had higher levels of sCD163 compared with controls (1.75 (0.47-6.90) and 1.36 (0.77-3.11) respectively, p

Thomsen, Henrik Holm; MØller, Holger Jon

2013-01-01

117

Simplified method for measuring sex-hormone binding globulin  

International Nuclear Information System (INIS)

We describe a simple, rapid method for measurement of sex-hormone binding globulin. Serial dilutions of pregnancy serum are prepared in serum from males that has been pre-treated by heating to 60 degrees C for 1 h to destroy endogenous binding globulin, which is then determined by a long-used technique to yield a set of ''standards.'' In the assay itself, a fixed amount of [3H]-labeled and unlabeled dihydrotestosterone is incubated with standard or unknown, and the bound fraction precipitated with saturated ammonium sulfate. A plot of percent of the steroid bound vs standard dilution yields a sigmoid curve, from which the results in unknowns can be read by simple extrapolation. Within-assay CVs for pools of serum from men, women, and women in late pregnancy were 6.56, 9.59, and 8.4%, respectively. Between-assay CVs for the same pools were 8.05, 9.5, and 11.5%, respectively. The correlation between results obtained by this method and those of the older technique was 0.95 for samples from non-pregnant subjects and 0.73 for those from pregnant women. Our procedure is simpler and faster than previous methods and accurately measures the differences in the globulin in sera from men, women, and pregnant women. Forty to 50 samples can be assayed in a working day

118

Simplified method for measuring sex-hormone binding globulin  

Energy Technology Data Exchange (ETDEWEB)

We describe a simple, rapid method for measurement of sex-hormone binding globulin. Serial dilutions of pregnancy serum are prepared in serum from males that has been pre-treated by heating to 60 degrees C for 1 h to destroy endogenous binding globulin, which is then determined by a long-used technique to yield a set of ''standards.'' In the assay itself, a fixed amount of (/sup 3/H)-labeled and unlabeled dihydrotestosterone is incubated with standard or unknown, and the bound fraction precipitated with saturated ammonium sulfate. A plot of percent of the steroid bound vs standard dilution yields a sigmoid curve, from which the results in unknowns can be read by simple extrapolation. Within-assay CVs for pools of serum from men, women, and women in late pregnancy were 6.56, 9.59, and 8.4%, respectively. Between-assay CVs for the same pools were 8.05, 9.5, and 11.5%, respectively. The correlation between results obtained by this method and those of the older technique was 0.95 for samples from non-pregnant subjects and 0.73 for those from pregnant women. Our procedure is simpler and faster than previous methods and accurately measures the differences in the globulin in sera from men, women, and pregnant women. Forty to 50 samples can be assayed in a working day.

Fattah, D.I.; Chard, T.

1981-07-01

119

Novel galanin receptors in teleost fish: identification, expression and regulation by sex steroids.  

Science.gov (United States)

In fish, the onset of puberty, the transition from juvenile to sexually reproductive adult animals, is triggered by the activation of pituitary gonadotropin secretion and its timing is influenced by external and internal factors that include the growth/adiposity status of the animal. Kisspeptins have been implicated in the activation of puberty but peripheral signals coming from the immature gonad or associated to the metabolic/nutritional status are also thought to be involved. Therefore we hypothesize the importance of the galinergic system in the brain and testis of pre-pubertal male sea bass as a candidate to translate the signals leading to activation of testicular maturation. Here, the transcripts for four galanin receptors (GALR), named GALR1a, 1b, 2a and 2b, were isolated from European sea bass, Dicentrarchus labrax. Phylogenetic analysis confirmed the previously reported duplication of GALR1 in teleost fish, and unravelled the duplication of GALR2 in teleost fish and in some tetrapod species. Comparison with human showed that the key amino acids involved in ligand binding are present in the corresponding GALR1 and GALR2 orthologs. Transcripts for all four receptors are expressed in brain and testes of adult fish with GALR1a and GALR1b abundant in testes and hardly detected in ovaries. In order to investigate whether GALR1 dimorphic expression was dependent on steroid context we evaluated the effect of 11-ketotestosterone and 17?-estradiol treatments on the receptor expression in brain and testes of pre-pubertal males. Interestingly, steroid treatments had no effect on the expression of GALRs in the brain while in the testes, GALR1a and GALR1b were significantly up regulated by 11KT. Altogether, these results support a role for the galaninergic system, in particular the GALR1 paralog, in fish reproductive function. PMID:25016048

Martins, Rute S T; Pinto, Patrícia I S; Guerreiro, Pedro M; Zanuy, Silvia; Carrillo, Manuel; Canário, Adelino V M

2014-09-01

120

Mono-hydroxy methoxychlor alters levels of key sex steroids and steroidogenic enzymes in cultured mouse antral follicles.  

Science.gov (United States)

Methoxychlor (MXC) is an organochlorine pesticide that reduces fertility in female rodents by decreasing antral follicle numbers and increasing follicular death. MXC is metabolized in the body to mono-hydroxy MXC (mono-OH). Little is known about the effects of mono-OH on the ovary. Thus, this work tested the hypothesis that mono-OH exposure decreases production of 17?-estradiol (E?) by cultured mouse antral follicles. Antral follicles were isolated from CD-1 mice (age 35-39 days) and exposed to dimethylsulfoxide (DMSO), or mono-OH (0.1-10 ?g/mL) for 96 h. Media and follicles were collected for analysis of sex steroid levels and mRNA expression, respectively. Mono-OH treatment (10 ?g/mL) decreased E(2) (DMSO: 3009.72±744.99 ng/mL; mono-OH 0.1 ?g/mL: 1679.66±461.99 ng/mL; 1 ?g/mL: 1752.72±532.41 ng/mL; 10 ?g/mL: 45.89±33.83 ng/mL), testosterone (DMSO: 15.43±2.86 ng/mL; mono-OH 0.1?g/mL: 17.17±4.71 ng/mL; 1 ?g/mL: 13.64±3.53 ng/mL; 10 ?g/mL: 1.29±0.23 ng/mL), androstenedione (DMSO: 1.92±0.34 ng/mL; mono-OH 0.1 ?g/mL: 1.49±0.43ng/mL; 1 ?g/mL: 0.64±0.31 ng/mL; 10 ?g/mL: 0.12±0.06 ng/mL) and progesterone (DMSO: 24.11±4.21 ng/mL; mono-OH 0.1?g/mL: 26.77±4.41 ng/mL; 1 ?g/mL: 20.90±3.75 ng/mL; 10 ?g/mL: 9.44±2.97 ng/mL) levels. Mono-OH did not alter expression of Star, Hsd3b1, Hsd17b1 and Cyp1b1, but it did reduce levels of Cyp11a1, Cyp17a1 and Cyp19a1 mRNA. Collectively, these data suggest that mono-OH significantly decreases levels of key sex steroid hormones and the expression of enzymes required for steroidogenesis. PMID:20840852

Craig, Zelieann R; Leslie, Traci C; Hatfield, Kimberly P; Gupta, Rupesh K; Flaws, Jodi A

2010-12-01

 
 
 
 
121

Sex steroids do not affect shigatoxin cytotoxicity on human renal tubular or glomerular cells  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The greater susceptibility of children to renal injury in post-diarrheal hemolytic-uremic syndrome (HUS may be related, at least in part, to heightened renal cell sensitivity to the cytotoxic effect of Shiga toxin (Stx, the putative mediator of kidney damage in HUS. We hypothesized that sexual maturation, which coincides with a falling incidence of HUS, may induce a relatively Stx-resistant state in the renal cells. Methods Cultured human glomerular endothelial (HGEN, human glomerular visceral epithelial (HGEC and human proximal tubule (HPT cells were exposed to Stx-1 after pre-incubation with progesterone, ?-estradiol or testosterone followed by determination of cytotoxicity. Results Under basal conditions, Stx-1 potently and dose-dependently killed HPT and HGEC, but had relatively little effect on HGEN. Pre-incubation for 1, 2 or 7 days with physiologic or pharmacologic concentrations of progesterone, ?-estradiol or testosterone had no effect on Stx-1 cytotoxicity dose-response on any cell type. In addition, no steroid altered Gb3 expression (Stx receptor by any cell type at any time point. Conclusion These data do not support the notion that hormonal changes associated with puberty induce an Stx-resistant state within kidney cells.

Kohan Donald E

2002-08-01

122

Effects of steroids and sex reversal on intestinal absorption of L-[14C]leucine in vivo, in rainbow trout, Salmo gairdneri  

International Nuclear Information System (INIS)

The effects of steroids (17 alpha-methyltestosterone (MT), 17 beta-oestradiol (E2)), and of sex reversal (XX male) on intestinal absorption and accumulation of L-[14C]leucine (5 mM), were investigated in unanaesthetized rainbow trout (Salmo gairdneri), using an in vivo gut perfusion technique. Each steroid was luminally perfused through the gut at a concentration of 50 micrograms/ml perfusate, during five separate perfusions carried out on the same fish at 30-min intervals (perfusion periods 1 to 5), for a total of 120 min at 14 degrees. Experiments were also conducted on masculinized, genetically female trout (XX male) with steroid-free perfusate. MT treatment significantly increased the intestinal absorption of radioleucine during periods 1 and 2, whilst E2 was without effect. Neither MT nor E2 influenced intestinal accumulation (mid- and hindgut) of radioleucine, and accumulation of 14C-solutes in skeletal muscle. Sex reversal, however, whilst having no effect on leucine absorption, nevertheless significantly increased intestinal accumulation of radioleucine, and accumulation of 14C-solutes in skeletal muscle. The effects observed in the present study are in agreement with previous work in trout using everted gut sac preparations. It is suggested that the growth-promoting effects of anabolic-androgenic steroids in fish may be partly explained by their action on gastrointestinal function

123

An immunohistochemical analysis of sex-steroid receptors, tumor suppressor gene p53 and Ki-67 in the normal and neoplastic uterine cervix squamous epithelium  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. Malignant transformation of sex-steroid dependent tissues is associated with the loss of expression of sex steroid receptors as well as of the tumor suppression gene p53. The aim of this study is to evaluate the expression of sex-steroid receptors, p53 and Ki-67 in specimens from pre-malignant and malignant cervical epithelial lesions throughout the menstrual cycle. Material and Methods. Immunohistochemical staining was performed on formalin fixed, paraffin embedded tissue sections of normal squamous cervical epithelium, cervical intraepithelial neoplasia and invasive squamous cervical carcinoma, specimens utilizing antibodies against estrogen receptors, progesterone receptors, p53 protein and Ki-67 antigen. Results. In the samples taken from the normal cervical tissue, basal cells were usually estrogen receptor-positive, progesterone receptornegative, p53-negative and Ki-67-negative throughout the menstrual cycle. In contrast, para-basal cells were estrogen receptorpositive and progesterone receptor-negative in the follicular phase, but estrogen receptor-negative and progesterone receptor -positive and Ki-67 positive in the luteal phase. In cervical precancerous and cancer tissue samples (cervical intraepithelial neoplasia and squamous cervical carcinoma, the expression of estrogen receptors decreased. 31.15% of cervical intraepithelial neoplasia and 11.5% of squamous cervical carcinoma were positive for estrogen receptors. However, the expression of progesterone receptors increased. 29.5% of cervical intraepithelial neoplasia and 49.2% of squamous cervical carcinoma were positive for progesterone receptors. Positive staining for p53 was observed in 15 (24.59% cases of cervical intraepithelial neoplasia and in 39 (64% of squamous cervical carcinoma. The expression Ki-67 index in squamous cervical carcinoma cases (47.60% was significantly higher than of cervical intraepithelial neoplasia cases (30.2% (p=0.041. Conclusion. The findings of this study suggest that tumor cervical cells evade normal growth control by sex steroid hormones while synchronously abnormal regulatory mechanisms acquire control of the cell cycle.

Nikolaou Marinos

2014-01-01

124

Inhaled Steroids  

Science.gov (United States)

... Diseases > Long-Term Control Medications > Inhaled Steroids Inhaled Steroids What are some common inhaled steroids? How are ... more about steroids? What are some common inhaled steroids? Common inhaled steroids include: Asmanex ® (mometasone) Alvesco ® (ciclesonide) ...

125

Decreased glutathione S-transferase expression and activity and altered sex steroids in Lake Apopka brown bullheads (Ameriurus nebulosus)  

Science.gov (United States)

A number of freshwater lakes and reclaimed agricultural sites in Central Florida have been the receiving waters for agrochemical and municipal runoff. One of these sites, Lake Apopka, is also a eutrophic system that has been the focus of several case studies reporting altered reproductive activity linked to bioaccumulation of persistent organochlorine chemicals in aquatic species. The present study was initiated to determine if brown bullheads (Ameriurus nebulosus) from the north marsh of Lake Apopka (Lake Apopka Marsh) exhibit an altered capacity to detoxify environmental chemicals through hepatic glutathione S-transferase (GST)-mediated conjugation as compared with bullheads from a nearby reference site (Lake Woodruff). We also compared plasma sex hormone concentrations (testosterone, 17-?? estradiol, and 11 keto-testosterone) in bullheads from the two sites. Female bullheads from Lake Apopka had 40% lower initial rate GST conjugative activity toward 1-chloro-2,4-dinitrobenzene (CDNB), 50% lower activity towards p-nitrobutyl chloride (NBC), 33% lower activity toward ethacrynic acid (ECA), and 43% lower activity toward ??5-androstene-3,17-dione (??5-ADI), as compared with female bullheads from Lake Woodruff. Enzyme kinetic analyses demonstrated that female bullheads from Lake Apopka had lower GST-catalyzed CDNB clearance than did female Lake Woodruff bullheads. Western blotting studies of bullhead liver cytosolic proteins demonstrated that the reduced GST catalytic activities in female Lake Apopka bullheads were accompanied by lower expression of hepatic GST protein. No site differences were observed with respect to GST activities or GST protein expression in male bullheads. Female Lake Apopka bullheads also had elevated concentrations of plasma androgens (testosterone and 11-ketotestosterone) as compared with females from Lake Woodruff. In contrast, male Lake Apopka bullheads had elevated levels of plasma estrogen but similar levels of androgens as compared with male bullheads from Lake Woodruff. Collectively, our studies indicate the presence of reduced GST protein expression, reduced GST conjugative capacity and altered sex steroid homeostasis in female bullheads from a contaminated field site in Central Florida. The implications of these physiological alterations in terms of pollutant biotransformation and reproduction are discussed. ?? 2001 Elsevier Science B.V. All rights reserved.

Gallagher, E.P.; Gross, T.S.; Sheehy, K.M.

2001-01-01

126

Control of the level of unusual estrogen-binding protein in rat liver by sex steroids and the pituitary  

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This paper studies the role of sex steriods and the pituitary in regulation of the unusual estrogen-binding protein (UEBP) level in male rat liver. The concentration of E/sub 2/-binding sites of UEBP in the liver cytosol was determined by measuring binding of a minimal addition of 2,4,6,7-tritium-E/sub 2/, with specific radioactivity of 98-100 Ci/mmole. Data on the effect of hypophysectomy on the UEBP level in the liver of different groups of rats are presented. The presence of comparable quantities of E/sub 2/ and androgens in rats of both sexes is evidence of the existence of a fine mechanism of combined regulation of the UEBP concentration under natural conditions that reflect changes in the absolute E/sub 2/ or androgen levels or in the ratio between them.

Smirnova, O.V.; Rozen, V.B.; Vishnyakova, T.G.

1986-02-01

127

Control of the level of unusual estrogen-binding protein in rat liver by sex steroids and the pituitary  

International Nuclear Information System (INIS)

This paper studies the role of sex steriods and the pituitary in regulation of the unusual estrogen-binding protein (UEBP) level in male rat liver. The concentration of E2-binding sites of UEBP in the liver cytosol was determined by measuring binding of a minimal addition of 2,4,6,7-tritium-E2, with specific radioactivity of 98-100 Ci/mmole. Data on the effect of hypophysectomy on the UEBP level in the liver of different groups of rats are presented. The presence of comparable quantities of E2 and androgens in rats of both sexes is evidence of the existence of a fine mechanism of combined regulation of the UEBP concentration under natural conditions that reflect changes in the absolute E2 or androgen levels or in the ratio between them

128

Plasma sex steroids and tissue aromatization in hatchling zebra finches: implications for the sexual differentiation of singing behavior.  

Science.gov (United States)

One of the best examples for sex hormone regulation of brain development is found in songbirds. In zebra finches, only males sing because of striking sex differences in the neural circuitry that controls songs. Because developing females treated with estradiol (E2) develop a masculine song system, E2 is considered the normal masculinizing hormone. However, questions about the role of E2 in male development persist, because E2 treatments that masculinize song can demasculinize other sexual behaviors, and there exists contradictory evidence for high levels of circulating E2 in developing males. We remeasured plasma steriods in zebra finches during the first 13 days after hatching. E2 circulated at low levels, and there were no sex differences in circulating E2, estrone, testosterone, androstenedione, or dihydrotestosterone. We also measured aromatase activity [( 3H]androstenedione conversion to [3H]estrone and [3H]E2) in gonad, adrenal, brain, and other tissues of hatchlings. Aromatase was abundant in ovary, but was not definitively detected in testes, adrenals, or other nonneural tissues of males. Aromatase was also found in diencephalon and in high amounts in telencephalon, but sex differences were not detected in whole brain or cellular subfractions of telencephalon. Because ovarian steroidogenesis is high, it may be involved in differentiation of the female zebra finch, as in nonpasserine birds. By contrast, the functional estrogen necessary for masculinization of song is most likely derived from brain, supplied with substrate from the adrenals. The puzzle remains why the song system is not masculinized in females, who possess high levels of aromatizable androgens and telencephalic aromatase. PMID:1727704

Schlinger, B A; Arnold, A P

1992-01-01

129

Histologia mamária após uso de esteróides sexuais - estudo em ratas / Breast histologic changes in female rats treated with sex steroids  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Avaliar as alterações histológicas em mamas de ratas submetidas à terapêutica com estrogênio, progestogênio e tibolona. MÉTODOS: Estudo experimental com 40 ratas, sendo 20 sem prole (grupo A) e 20 com prole (grupo B). Todas as ratas foram castradas e, após quatro semanas, alocadas aleatori [...] amente em subgrupos: A1, A2, A3, A4, A5 e B1, B2, B3, B4, B5. Os esteróides foram administrados da seguinte forma: A1 e B1 - benzoato de estradiol; A2 e B2 - acetato de medroxiprogesterona; A3 e B3 - benzoato de estradiol e acetato de medroxiprogesterona; A4 e B4 - tibolona; A5 e B5 - placebo. Após dez semanas de tratamento, os animais foram sacrificados e suas glândulas mamárias submetidas à análise histológica. Os parâmetros avaliados foram: proliferação epitelial, atividade secretora e atipias epiteliais nas unidades de ductos ou alvéolos terminais. A associação entre os achados histológicos e os esquemas terapêuticos foi avaliada por meio do odds ratio e intervalo de confiança de 95%. RESULTADOS: Alterações histológicas foram observadas em 29 ratas: hiperplasia moderada (52,5%), hiperplasia alvéolo-nodular (42,5%), atipia sem proliferação (35%), hiperplasia leve (32,5%), atividade secretora (20%) e hiperplasia severa (5%). Em ratas sem prole observou-se 1,3 mais chance, em relação ao grupo controle, de apresentar hiperplasia alvéolo-nodular no grupo que recebeu estrogênio, hiperplasia moderada no grupo tratado com progestogênio, e hiperplasia alvéolo-nodular e atipia sem proliferação epitelial com a associação entre estrogênio e progestogênio. CONCLUSÃO: Hiperplasia moderada e atipia epitelial associaram-se à terapia combinada de estrogênio e progestogênio, e o antecedente de prole reduziu a ocorrência destas alterações e de hiperplasia alvéolo-nodular. Abstract in english OBJECTIVE: To evaluate the association of histologic changes in the breasts of female rats undergoing therapy with sex steroids. METHODS: An experimental study was conducted of 40 castrated female non-pubertal rats, 20 had given birth (Group B) and 20 had no offspring (Group A). After four weeks, th [...] ese rats were randomly allocated to subgroups: A1, A2, A3, A4, A5 and B1, B2, B3, B4, B5. Steroids were given to subgroups as follows: A1 and B1 - estradiol benzoate; A2 and B2 - medroxyprogesterone acetate; A3 and B3 - estradiol benzoate and medroxyprogesterone acetate; A4 and B4 - tibolone; A5 and B5 - placebo. After 10 weeks of treatment, animals were sacrificed and their mammary glands were analyzed. Histologic parameters evaluated were: epithelial cell proliferation, epithelial cells with secretory activity; and cell atypia in terminal duct units and buds or terminal alveoli. The association between microscopic analysis and diverse therapeutic regimens were analyzed by calculating the odds ratio and its respective 95% confidence interval. RESULTS: Histologic changes were observed in 29 rats: moderate hyperplasia (52.5%), hyperplastic alveolar nodule (42.5%), epithelial atypia (35%), mild hyperplasia (32.5%), secretory activity (20%) and severe hyperplasia (5%). In rats with no offspring when compared to the control, 1.3 times more hyperplastic alveolar nodules were found in the group treated with estradiol, the same was true for moderate hyperplasia in the rats that received medroxyprogesterone acetate, hyperplastic alveolar nodules and epithelial atypia in the group treated with estradiol plus medroxyprogesterone acetate. In the rats with offspring 1.3 times more secretory activity was found with estradiol. CONCLUSION: Epithelial hyperplasia and epithelial atypia with no proliferation are strongly associated to combined therapy with estradiol plus medroxyprogesterone acetate, mainly in the rats without offspring.

José Tadeu, Vicelli; Maria Salete Costa, Gurgel; Marcelo, Alvarenga.

2006-10-01

130

Melatonin reduces LH, 17 beta-estradiol and induces differential regulation of sex steroid receptors in reproductive tissues during rat ovulation  

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Full Text Available Abstract Background Melatonin is associated with direct or indirect actions upon female reproductive function. However, its effects on sex hormones and steroid receptors during ovulation are not clearly defined. This study aimed to verify whether exposure to long-term melatonin is able to cause reproductive hormonal disturbances as well as their role on sex steroid receptors in the rat ovary, oviduct and uterus during ovulation. Methods Twenty-four adult Wistar rats, 60 days old (+/- 250 g were randomly divided into two groups. Control group (Co: received 0.9% NaCl 0.3 mL + 95% ethanol 0.04 mL as vehicle; Melatonin-treated group (MEL: received vehicle + melatonin [100 ?g/100 g BW/day] both intraperitoneally during 60 days. All animals were euthanized by decapitation during the morning estrus at 4 a.m. Results Melatonin significantly reduced the plasma levels of LH and 17 beta-estradiol, while urinary 6-sulfatoximelatonin (STM was increased at the morning estrus. In addition, melatonin promoted differential regulation of the estrogen receptor (ER, progesterone receptor (PR, androgen receptor (AR and melatonin receptor (MTR along the reproductive tissues. In ovary, melatonin induced a down-regulation of ER-alpha and PRB levels. Conversely, it was observed that PRA and MT1R were up-regulated. In oviduct, AR and ER-alpha levels were down-regulated, in contrast to high expression of both PRA and PRB. Finally, the ER-beta and PRB levels were down-regulated in uterus tissue and only MT1R was up-regulated. Conclusions We suggest that melatonin partially suppress the hypothalamus-pituitary-ovarian axis, in addition, it induces differential regulation of sex steroid receptors in the ovary, oviduct and uterus during ovulation.

Pinheiro Patrícia Fernanda F

2011-08-01

131

Effect of GnRHa, pimozide and Ovaprim on ovulation and plasma sex steroid hormones in African catfish Clarias gariepinus.  

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Nine groups each of four fish were injected with a single intramuscular dose of the following preparations: Physiological saline (0.9% NaCl) as a control group, 0.5 ml kg(-1) Ovaprim, 20 and 40 ?g kg(-1) BW of GnRHa, 8 and 16 mL kg(-1) pimozide tablets and the following combination of GnRHa with pimozide (GP): 20 ?g + 4 mg, 30 ?g + 8 mg and 40 ?g + 16 mg kg(-1) BW. The primary oocyte diameter (POD) before hormone administration ranged from 943.3 to 1071.0 ?m. The latency periods (LP) were in the range of 9.0 to 12.0 h after injection. The highest ovulation ratio (OR) was observed in groups Ovaprim, GP(30 + 8) and GP(40 + 16). Other treatments were effective for ovulation, the ovulation ratio in Groups G(40) and GP(20 + 4) were significantly higher than G(20) treatment. The ovulation index (OI) was in the range 62 to 77% and showed significant differences among groups. There was no significant difference in fertilization ratio (FR) among Ovaprim, GP(30 + 8) and GP(40 + 16) groups, while there were significant difference between the previous group and G(20) and G(40) groups. Control, P8, P16 showed negative results in all the parameters LP, OED, OR, OI and FR. Levels of sex steroids were analyzed on 6 and 12 h after initiation of treatments. A significant increase in plasma E(2) with GP(30 + 8) injection was observed 6 and 12 h after injection, while there were no significant increase between all the other groups 6 h after injection. Treatments with GP(20 + 4) resulted in a significant increase in plasma T concentration in females compared with control after 6 h. In contrast, plasma T and E(2) concentrations were lower during the combined GP(20 + 4), GP(30 + 8) and GP(40 + 16) after 12 h than after 16 h of injection. The combined treatments (GnRHa + PIM) are better compared with Ovaprim which gave the same results, they have some advantages, such as reliable response and low cost. Ovaprim is more than 3 to 5-fold of the cost of (GnRH + PIM). Therefore, this method could be useful tool for commercial catfish breeders to ensure spawning success. PMID:22365698

Sharaf, S M

2012-05-01

132

Impact of photoperiod manipulation on day/night changes in melatonin, sex steroids and vitellogenin plasma levels and spawning rhythms in Senegal sole, Solea senegalensis.  

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Photoperiod and temperature are known as the main synchronizers of seasonal reproduction in fish. This paper studied the role of photoperiod on the synchronization of F1 Senegal sole reproduction rhythms. Fish were maintained under constant short-photoperiod (9L:15D) from the winter solstice onwards (experimental group) or under naturally-changing photoperiod (control group), and water temperature naturally oscillated in both groups. Blood samples were collected during the reproduction season at pre-spawning (March), spawning (April) and post-spawning (May) to determine the endocrine status. Spawning events and egg quality parameters were also monitored. The results revealed a significant increase in nocturnal melatonin concentration from March to May in the control group, while in the experimental group such seasonal change did not occur. As to plasma levels of vitellogenin, testosterone, estradiol and 11keto-testosterone, differences between groups were found mostly in March, while in April and May levels were often similar. Spawning was observed in both groups, although the experimental group started slightly earlier and also finished earlier than the control group, perhaps as a result of the increase in sex steroids and VTG observed at pre-spawning. Briefly, reproduction rhythms persisted in the absence of the natural lengthening of photoperiod, although photoperiod manipulation altered the seasonal modulation of melatonin, increased sex steroids and vitellogenin at pre-spawning, and slightly advanced the timing of spawning. PMID:21466857

Oliveira, Catarina; Mañanós, Evaristo; Ramos, Jesus; Sánchez-Vázquez, Francisco Javier

2011-07-01

133

Sex estimation from sternal measurements using multidetector computed tomography.  

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We aimed to show the utility and reliability of sternal morphometric analysis for sex estimation.Sex estimation is a very important step in forensic identification. Skeletal surveys are main methods for sex estimation studies. Morphometric analysis of sternum may provide high accuracy rated data in sex discrimination. In this study, morphometric analysis of sternum was evaluated in 1 mm chest computed tomography scans for sex estimation. Four hundred forty 3 subjects (202 female, 241 male, mean age: 44 ± 8.1 [distribution: 30-60 year old]) were included the study. Manubrium length (ML), mesosternum length (2L), Sternebra 1 (S1W), and Sternebra 3 (S3W) width were measured and also sternal index (SI) was calculated. Differences between genders were evaluated by student t-test. Predictive factors of sex were determined by discrimination analysis and receiver operating characteristic (ROC) analysis. Male sternal measurement values are significantly higher than females (P sternum might provide important information for sex estimation. PMID:25501090

Ekizoglu, Oguzhan; Hocaoglu, Elif; Inci, Ercan; Bilgili, Mustafa Gokhan; Solmaz, Dilek; Erdil, Irem; Can, Ismail Ozgur

2014-12-01

134

Effects of partial or total fish meal replacement by agricultural by-product diets on gonad maturation, sex steroids and vitellogenin dynamics of African catfish (Clarias gariepinus).  

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The establishment of the first sexual maturation was characterized in African catfish (Clarias gariepinus) in order to study the efficiency of replacement of fish meal (FM) by diets composed of local vegetable ingredients. Four diets were formulated containing decreasing levels of FM (50-0% for diet 1 to diet 4) and increasing proportions of vegetable ingredients (50-100%). Gonadosomatic index (GSI), diameter and percentages of developmental stages of oocytes, plasma sex steroids and vitellogenin dynamics were investigated from February to June using one-year-old fish. Fish were individually tagged, and 12 individuals from each diet were investigated monthly. Replacement of FM with plant ingredients did not affect the GSI neither in males, nor in females. All males were spermiating, and no abnormal gonads were found. In females, GSI and percentages of advanced stages of oocytes decreased during the dry season, indicating seasonal changes in gonad development. Moreover, oocytes were in late exogenous vitellogenesis, but no final maturation stages were observed, whatever the diet. Higher plasma levels of E2 in females and of androgens (T and 11-KT) in both sexes were observed in fish fed diet 4 than in those receiving diet 1 depending on the season. Levels of plasma E2 and ALP (indicator for vitellogenin) in males did not differ among treatments and seasons suggesting no phytoestrogenic activity. The results showed that total replacement of FM by vegetable diets composed of groundnut oilcakes, bean and sunflower meals has no deleterious effect on the onset of sexual maturation in African catfish but, may stimulate the sex steroid production and in turns may potentially exert some positive actions on reproductive success. PMID:22382402

Nyina-wamwiza, L; Defreyne, P S; Ngendahayo, L; Milla, S; Mandiki, S N M; Kestemont, P

2012-10-01

135

Sex steroid binding protein exerts a negative control on estradiol action in MCF-7 cells (human breast cancer) through cyclic adenosine 3',5'-monophosphate and protein kinase A.  

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Estradiol is considered to be a critical factor in the growth induction of some breast cancer cells, like MCF-7 cell line. Among other compounds involved in the control of neoplastic mammary cell growth, cAMP has been suggested, on the other hand, to exert an antiproliferative effect. Sex steroid binding protein (SBP) sex hormone binding globulin (SHBG), the plasma carrier for both androgens and estradiol, recognizes a specific receptor located on membranes of estrogen- and androgen-sensitive...

Frairia, Roberto; Berta, Laura Adelaide Angela

1996-01-01

136

Possible mechanism for preterm labor associated with bacterial infection. II: Enhancement of endotoxin-stimulated phosphoinositide metabolism by sex steroids in human endometrial fibroblasts.  

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We have previously reported that bacterial endotoxin stimulated membrane phosphoinositide metabolism, which resulted in liberation of arachidonic acid and preterm initiation of parturition. The aim of this study was to explore whether ovarian steroids alter the stimulation of phosphoinositide turnover by endotoxin. The phosphoinositide turnover was evaluated by [32P] phosphate incorporation into phosphatidic acid (PA) and phosphatidylinositol (PI) in human endometrial fibroblasts. When the cells were exposed to endotoxin from Escherichia colli, 32P-labeling of PA and PI was increased in a dose-dependent manner; EC50 was 10 ng/ml. Preincubation with estradiol-17 beta (1 microM) and progesterone (1 microM) for 24 hours, but not for a few hours, enhanced the rate of the endotoxin-stimulated phosphorylation of the lipids in the fibroblasts by decreasing EC50 value of endotoxin to 1 ng/ml. Estradiol or progesterone alone failed to show any effects. These findings demonstrated that the sex steroids may increase the sensitivity of host cells to endotoxin, suggesting the mechanism(s) by which the preterm labor associated with intra-amniotic infection is initiated. PMID:2171112

Khan, A A; Imai, A; Tamaya, T

1990-07-01

137

Measurement of steroid hormones in saliva: Effects of sample storage condition.  

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Measurement of steroid hormones in saliva is increasingly common in elite sport settings. However, this environment may enforce handling and storage practices that introduce error in measurement of hormone concentrations. We assessed the influence of storage temperature and duration on reproducibility of salivary steroid levels. Nine healthy adults provided morning and afternoon saliva samples on two separate occasions. Each sample was divided into identical saliva aliquots which were stored long-term (i.e. 28 and 84 days) at - 80°C or - 20°C (testing day 1), and short-term (i.e. 1, 3, 7 and 14 days) at 4°C or 20°C (testing day 2). Samples were analyzed for cortisol, testosterone and estradiol using ELISA. In non-freezer conditions, there was a decrease from baseline to 7 days in testosterone (- 26 ± 15%) and estradiol (- 58 ± 17%) but not cortisol concentrations (p storage in freezer conditions (p ? 0.01), but these were generally within 12% of baseline concentrations, and may be partly explained by inter-assay variability. Whole saliva samples to be analyzed for cortisol, testosterone and estradiol should be frozen at - 20°C or below within 24 h of collection, and analyzed within 28 days. Storage of samples for measurement of testosterone and estradiol at temperatures above - 20°C can introduce large error variance to measured concentrations. PMID:24033227

Toone, Rebecca J; Peacock, Oliver J; Smith, Alan A; Thompson, Dylan; Drawer, Scott; Cook, Christian; Stokes, Keith A

2013-12-01

138

Standardization of androstenedione and estrone radioimmunoassay and profile of sex steroids, gonadotropins and prolactin - in patients with chronic anovulation due to inappropriate feedback (polycystic ovarian syndrome)  

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Full text. In order to evaluate the profile of the sex steroids gonadotropin and prolactin in polycystic ovarian syndrome (POS), 24 patients with POS were studied and compared with 20 normal women during the early follicular phase of the menstrual cycle. Radioimmunoassay techniques for androstenedione (A) and estrone (E1) were standardized for the purpose of the study. Androstenedione and estrone were extracted from plasma with ethyl ether. The assays were maintained in equilibrium and the labelled hormone-antibody complex was then separated from the free hormone using dextran charcoal. The sensitivity of the method was 6.8 pg/tube for A and 3.7 pg/tube for E1. Nonspecific binding ws 3.4 for A and 3.3 for E1. The interessay error at the D50 level was 15.6 for A and 8.6 for E1. Patients with POS had significantly higher basal levels of LH, A, T E1 and PRL and similar FSH and DHEA-S levels when compared with normal women. The LH/FSH ratio was significantly elevated and the A/T ratio was significantly decreased. The A/E1 and T/E2 ratios were elevated and the E1/E2 was decreased, although the differences were not statistically significant. A positive correlation between A and E1 was observed in patients with POS. In view of the above data, it was concluded that: the quality control parameters of the radioimmunoassay for A and E1 standardized in the presand E1 standardized in the present study are considered satisfactory, and the assay could be used for diagnosis and research; the patients with POS have a different sex steroid and gonadotropin profile when compared normal women during the early follicular phase of the menstrual cycle

139

Nitrite-induced alterations in sex steroids and thyroid hormones of Labeo rohita juveniles: effects of dietary vitamin E and L-tryptophan.  

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An experiment was conducted to study the effect of sub-lethal nitrite exposure on sex steroids (testosterone and estradiol), cortisol and thyroid hormones (T3 and T4) of Labeo rohita juveniles. Fishes previously fed with normal or elevated levels of vitamin E (VE) and tryptophan for 60 days were exposed to sub-lethal nitrite for another 45 days with same feeding regime. There were nine treatment groups, viz. VE0TRP0-N, VE0TRP0+N, VE100TRP0-N, VE100TRP0+N, VE100TRP0.75+N, VE100TRP1.5+N, VE150TRP0+N, VE300TRP0+N and VE200TRP1+N. Except the groups VE0TRP0-N and VE100TRP0-N, all other groups were exposed to nitrite. At the end of the 45 days of nitrite exposure, serum samples were assayed for sex steroids, cortisol and thyroid hormones. The serum T3 and T4 levels decreased to the extent of 84.5 and 94.06%, respectively, upon nitrite exposure. Dietary supplementation with additional amounts of VE and tryptophan appears to reduce the decline of the production of T4. The serum testosterone and estradiol decreased 97.31 and 92.86%, respectively, upon nitrite exposure. Supplementation with additional amounts of VE was found to reverse nitrite-induced inhibition of testosterone and estradiol production. Serum cortisol increased upon nitrite exposure and unexposed (VE100-N) group showed lower levels, which were comparable to groups fed with elevated levels of VE. The overall results of the present study revealed that environmental nitrites have a negative impact on steroidogenesis, which can be overcome by dietary supplementation of elevated amounts of VE (minimum of 150 mg VE Kg diet(-1)) and to a lesser extent by tryptophan (only at the level of 1.5% of the diet). PMID:23504103

Ciji, A; Sahu, N P; Pal, A K; Akhtar, M S

2013-10-01

140

The effect of sex steroid hormones on brain edema and intracranial pressure after experimental traumatic brain injury in rats  

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Full Text Available Introduction: We investigated the role of sex hormones on changes in brain edema intracranialpressure (ICP, cerebral perfusion pressure (CCP after trauma brain injury (TBI in ovarectomizedfemale (OVX rats.Material and Methods: In this study female rats are divided into five groups. Control group(Intact sham group and other groups include: vehicle, estrogen group (1mg/kg and progesteronegroup (8 mg/kg which on all groups TBI was induced by Marmarou method. 30 minutes after TBI,drugs were injected i.p. ICP was measured in spinal cord using a standard procedure. CPP wascalculated by the mean arterial pressure (MAP - ICP. Neurologic scores were measured by motor,eye and respiratory reflexResults: The results showed after TBI, water content was significantly lower in estrogen andprogesterone groups (P<0.001 compared with vehicle group. Analysis showed a stable ICP up to 24hours. The ICP in estrogen and progesterone groups was significantly decreased at 4 and 24 hours ascompared to vehicle group (P<0.001in both cases. The CPP at 24 hours after TBI, significantlyincreased in estrogen and progesterone groups compared with vehicle (P<0.001. Also after TBI,neurologic scores was significantly higher in estrogen and progesterone groups as compared withvehicle (at 1hours P<0.05, and at 24hours P<0.001 for estrogen, (at 1hours P<0.01 for progesterone.Conclusion: Our findings indicated an improvement of ICP, CPP and neurologic scores producedby pharmacologic doses of estrogen and progesterone after TBI in OVX rat. These effects may becontribute to neuroprotective effects of these hormones.

Nader Shahrokhi

2008-08-01

 
 
 
 
141

Sex and exercise interact to alter the expression of anabolic androgenic steroid-induced anxiety-like behaviors in the mouse.  

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Anabolic androgenic steroids (AAS) are taken by both sexes to enhance athletic performance and body image, nearly always in conjunction with an exercise regime. Although taken to improve physical attributes, chronic AAS use can promote negative behavior, including anxiety. Few studies have directly compared the impact of AAS use in males versus females or assessed the interaction of exercise and AAS. We show that AAS increase anxiety-like behaviors in female but not male mice and that voluntary exercise accentuates these sex-specific differences. We also show that levels of the anxiogenic peptide corticotrophin releasing factor (CRF) are significantly greater in males, but that AAS selectively increase CRF levels in females, thus abrogating this sex-specific difference. Exercise did not ameliorate AAS-induced anxiety or alter CRF levels in females. Exercise was anxiolytic in males, but this behavioral outcome did not correlate with CRF levels. Brain-derived neurotrophic factor (BDNF) has also been implicated in the expression of anxiety. As with CRF, levels of hippocampal BDNF mRNA were significantly greater in males than females. AAS and exercise were without effect on BDNF mRNA in females. In males, anxiolytic effects of exercise correlated with increased BDNF mRNA, however AAS-induced changes in BDNF mRNA and anxiety did not. In sum, we find that AAS elicit sex-specific differences in anxiety and that voluntary exercise accentuates these differences. In addition, our data suggest that these behavioral outcomes may reflect convergent actions of AAS and exercise on a sexually differentiated CRF signaling system within the extended amygdala. PMID:24768711

Onakomaiya, Marie M; Porter, Donna M; Oberlander, Joseph G; Henderson, Leslie P

2014-07-01

142

Brief exposure of embryos to steroids or aromatase inhibitor induces sex reversal in Nile tilapia (Oreochromis niloticus).  

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This study aimed to develop sex reversal procedures targeting the embryonic period as tools to study the early steps of sex differentiation in Nile tilapia with XX, XY, and YY sexual genotypes. XX eggs were exposed to masculinizing treatments with androgens (17?-methyltestosterone, 11-ketotestosterone) or aromatase inhibitor (Fadrozole), whereas XY and YY eggs were subjected to feminizing treatments with estrogen analog (17?-ethynylestradiol). All treatments consisted of a single or double 4-hr immersion applied between 1 and 36?hour post-fertilization (hpf). Concentrations of active substances were 1000 or 2000??g l(-1) in XX and XY, and 2000 or 6500??g l(-1) in YY. Masculinizing treatments of XX embryos achieved a maximal sex reversal rate of 10% with an exposure at 24?hpf to 1000??g l(-1) of 11-ketotestosterone or to 2000??g l(-1) of Fadrozole. Feminization of XY embryos was more efficient and induced up to 91% sex reversal with an exposure to 2000??g l(-1) of 17?-ethynylestradiol. Interestingly, similar treatments failed to reverse YY fish to females, suggesting either that a sex determinant linked to the Y chromosome prevents the female pathway when present in two copies, or that a gene present on the X chromosome is needed for the development of a female phenotype. J. Exp. Zool. 323A: 31-38, 2015. © 2014 Wiley Periodicals, Inc. PMID:25376842

Gennotte, Vincent; Mafwila Kinkela, Patrick; Ulysse, Bernard; Akian Djétouan, Dieudonné; Bere Sompagnimdi, Frédéric; Tomson, Thomas; Mélard, Charles; Rougeot, Carole

2015-01-01

143

Oral Steroids (Steroid Pills and Syrups)  

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... Lung Diseases > Quick-Relief Medications > Oral Steroids Oral Steroids (Steroid Pills and Syrups) How are steroid pills and ... Want to learn more about steroids? How are steroid pills and syrups used? Steroid pills and syrups ...

144

Application of Double Isotope Derivative Dilution Procedures to Steroid Hormone Measurement  

International Nuclear Information System (INIS)

The measurement of the concentration of specific steroid hormones in human peripheral plasma has required the development of sensitive analytical procedures. Of the various analytical techniques available, procedures based on the principle of double isotope derivative dilution have great specificity and precision at low levels, and can be readily applied to the measurement of androgens, oestrogens, progesterone and adrenocortical hormones. In these procedures a known amount of 14C- or 3H-labelled steroid is added to the sample as an internal recovery indicator to account for losses over the various analytical steps. Mass is determined by formation of a labelled derivative of the hormone following reaction with a radioactive reagent of known specific activity. These reagents are usually either 3H- or 35S-labelled. Separation of the various steroid hormones from each other and from the excess radioactivity arising from derivative formation is carried out by chromatography and by further chemical modification of the labelled derivative. The problems of developing a method suitable for the measurement of aldosterone in human peripheral plasma are described, and a comparison made between two methods, one which uses 14C-aldosterone as internal indicator and 3H-acetic anhydride for derivative formation, and another which uses 3H-aldosterone and 35S-tosan (toluene sulphonic acid anhydride). The subsequent modification of the basic 3H-acetic anhydride procedure to enable simultaneous measurement of cortisol, cortisone, corticosterone, desoxycortisol, desoxycorticosterone, dehydroepiandrosterone and testosterone in a single sample are described. The application of these procedures to the measurement of progesterone and oestrone and oestradiol- 178 are also discussed; in particular, the enzymatic reduction of progesterone to enable acetylation, or the use of 35S-pipsyl chloride (p-iodo benzene sulphonyl chloride) for derivative formation. The advantages and disadvantages of this type of methodology are also discussed with particular reference to specificity, accuracy, precision and suitability for routine analytical use. The sensitivity and precision of double isotope methodology is dependent not only on the specific activity of the labelled reagents but also on the performance of the liquid scintillation counting system. Statistical counting errors and an assessment of the precision and reliability of liquid scintillation counting systems used to count samples containing 3H and 14C are described. (author)

145

Manipulation of the periovulatory sex steroidal milieu affects endometrial but not luteal gene expression in early diestrus Nelore cows.  

Science.gov (United States)

In beef cattle, the ability to conceive has been associated positively with size of the preovulatory follicle (POF). Proestrus estradiol and subsequent progesterone concentrations can regulate the endometrium to affect receptivity and fertility. The aim of the present study was to verify the effect of the size of the POF on luteal and endometrial gene expression during subsequent early diestrus in beef cattle. Eighty-three multiparous, nonlactating, presynchronized Nelore cows received a progesterone-releasing device and estradiol benzoate on Day-10 (D-10). Animals received cloprostenol (large follicle-large CL group; LF-LCL; N = 42) or not (small follicle-small CL group; SF-SCL; N = 41) on D-10. Progesterone devices were withdrawn and cloprostenol administered 42 to 60 hours (LF-LCL) or 30 to 36 hours (SF-SCL) before GnRH treatment (D0). Tissues were collected at slaughter on D7. The LF-LCL group had larger (P gene expression of vascular endothelial growth factor A, kinase insert domain receptor, fms-related tyrosine kinase 1, steroidogenic acute regulatory protein, cytochrome P450, family 11, subfamily A, polypeptide 1, and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 7 was similar between groups. Endometrial gene expression of oxytocin receptor and peptidase inhibitor 3, skin-derived was reduced, and estrogen receptor alpha 2, aldo-keto reductase family 1, member C4, and lipoprotein lipase expression was increased in LF-LCL versus SF-SCL. Results support the hypothesis that the size of the POF alters the periovulatory endocrine milieu (i.e., proestrus estradiol and diestrus progesterone concentrations) and acts on the uterus to alter endometrial gene expression. It is proposed that the uterine environment and receptivity might also be modulated. Additionally, it is suggested that increased progesterone secretion of cows ovulating larger follicles is likely due to increased CL size rather than increased luteal expression of steroidogenic genes. PMID:24507960

Mesquita, F S; Pugliesi, G; Scolari, S C; França, M R; Ramos, R S; Oliveira, M; Papa, P C; Bressan, F F; Meirelles, F V; Silva, L A; Nogueira, G P; Membrive, C M B; Binelli, M

2014-04-01

146

Sex determination using patella metrical measurements: Iranian cadavers  

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Full Text Available "n Normal 0 false false false EN-GB X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: One of the major problems in the medicine is personal identification in cases of skeletal remains. The first step is determination of sex. One of the elements that recently paied more attention to it is the patella. Since the measurements are population specific, so we measured the patellas of Iranians to determine their patellas dimensions for sex prediction."n"nMethods: In this study three metrical characteristics of patella were measured from 67 corps between 20-64 years refered to the autopasy hall of forensic medicine center in Tehran (L.M.O. For statistical analysis of datas, the statistical product and service solution (SPSS version 16 program was used and unvariate and multivariate discriminant function analysis were performed to indicate the efficiency of each variable for sex determination."n"nResults: The mean of patella height in male was 4.46 cm and in female was 3.87, the mean of patella width in male was 4.60 and in female was 4.03cm and the mean of patella thickness in male was 2.25 and in female was 2.07cm. Among these measurements maximal width with average accurancy of 94% and then maximal height with 91% and finally maximal thickness with 71.6-73.1% respectively were better variables for sex determination. Also in multivariate discriminant analysis, combination of all three measurements with average accuracy of 94% was the best function for sex determination."n"nConclusion: The results of this study revealed that we can determine sex with high confidence in situations such as explosions, air crashes and etc, just by using the patella measurement.

Akhlaghi M

2009-06-01

147

Involvement of Gonadal Steroids and Gamma Interferon in Sex Differences in Response to Blood-Stage Malaria Infection†  

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To examine the hormonal and immunological mechanisms that mediate sex differences in susceptibility to malaria infection, intact and gonadectomized (gdx) C57BL/6 mice were inoculated with Plasmodium chabaudi AS-infected erythrocytes, and the responses to infection were monitored. In addition to reduced mortality, intact females recovered from infection-induced weigh loss and anemia faster than intact males. Expression microarrays and real-time reverse transcription-PCR revealed that gonadally...

Cernetich, Amy; Garver, Lindsey S.; Jedlicka, Anne E.; Klein, Pamela W.; Kumar, Nirbhay; Scott, Alan L.; Klein, Sabra L.

2006-01-01

148

EFFECTS OF THREE DIFFERENT GONADOTROPIN - RELEASING HORMONE ANALOGUES COMBINED WITH DOPAMINE ANTAGONISTS ON PLASMA SEX STEROID HORMONES, IN ENDANGERED MALE AND FEMALE CASPIAN BROWN TROUT, SALMO TRUTTA CASPIUS  

Directory of Open Access Journals (Sweden)

Full Text Available To understand the steroidogenic activities in Caspian brown trout, female and male broodstocks were injected with three different GnRHa in combination with two different dopamine antagonists and we examined changes in plasma sex steroid hormones during the experiments. In four separate experiments, female and male received two injections (at 0 day and 4 day in total volume 0.5 and 0.25 ml per kg-1 body weight respectively. Control group received only propylene glycol (Vehicle only. The final concentrations of GnRHa and metoclopramide (MET were 20 µg GnRHa kg-1 body weight (BW and 10 mg kg-1 body weight (BW, respectively. Each injection, received half dose of hormone. Blood samples were taken at 0, 2, 5 and 7 days, and blood plasma was retained for analysis of steroid levels. In female, plasma levels of estradiol-17? (E2 and testosterone (T showed significant decreases in fish treated with GnRHa plus Dopamine antagonist compared to control group. Plasma 17?,20?-dihydroxy-4-pregnen-3-one (17,20?-P levels abruptly increased at the 2nd day post-injection in all treated groups, reached peak levels at the 5th day, and the elevated levels slightly decreased by the 7th day. In male, all experimental treatments showed lower blood plasma 11-ketotestosterone (11KT levels relative to control. Treatment in all hormonal groups resulted in significant decrease in blood plasma 17,20?P levels compared to control group except fish treated with mGnRHa in combination with metoclopramide at 2nd post injection. Mean blood plasma T levels displayed a marked increase between 2nd and 5thyad . Changes in plasma T levels showed no significant change at the 7th day post injection.

Seyed Ehsan Mousavi

2013-08-01

149

Sex-specific effects of gestational and lactational coexposure to lead and cadmium on hepatic phase I and phase II xenobiotic/steroid-metabolizing enzymes and antioxidant status.  

Science.gov (United States)

Liver has evolved complex enzymatic mechanisms to detoxify a wide array of xenobiotic substances, ranging from dietary components to environmental toxins to pharmaceuticals. Activities of many steroid-metabolizing enzymes in adult rat liver microsomes are sexually differentiated. Toxic effects of lead and cadmium on hepatic tissue have been well established in our earlier studies. We thus monitored the effects of gestational and lactational coexposure to lead and cadmium on hepatic phase I and phase II xenobiotic- and steroid-metabolizing enzyme activities in both male and female F1 generation postnatal day (PND) 56 rats. Adult pregnant female rats were treated subcutaneously [0.05 mg/(kg body wt. day)] with sodium acetate (control group), lead acetate, and cadmium acetate separately and in combination throughout the gestational and lactational period. Hepatic phase I xenobiotic-metabolizing enzymes (NADPH- and NADH-cytochrome c reductase) activities significantly decreased significantly in all the metal-treated groups in both PND 56 male and female rats as compared with the control group. Hepatic phase II enzymes (uridine diphosphate-glucuronosyl transferase, gamma-glutamyl transpeptidase, glutathione-S-transferase, 17-beta-hydroxysteroid oxidoreductase) were also highly susceptible to all the metal-treated groups. The observed alterations in the oxidative stress and biochemical parameters in the liver of F1 generation male and female rats resulted from an independent effect of lead and/or cadmium and also from their interaction. Results suggest that early developmental exposure to lead and cadmium both alone and in combination can suppress the hepatic xenobiotic-metabolizing enzyme activities in the liver of F1 generation male and female rats in a sex-dependent manner. PMID:20024958

Pillai, Prakash; Patel, Ritesh; Pandya, Chirayu; Gupta, Sarita

2009-01-01

150

In vivo effects of oLH and LHRH-analog on sex reversal and plasma sex steroid profiles in the female Monopterus albus.  

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The effects of ovine-luteinizing hormone (oLH) or a synthetic analog of luteinizing hormone-releasing hormone, Des-Gly10[S-Ala6]-LHRH ethylamide acetate salt (LHRH-A), on the female phase of the protogynous Monopterus albus were investigated, and the plasma levels of androstenedione (Ad), testosterone (T), 11-oxotestosterone (KT), 11 beta-hydroxytestosterone (OHT), 17 beta-estradiol (E2) and progesterone were determined. In the postspawning stage, oLH induced precocious sex reversal in the gonad from female to male and increased plasma levels of Ad, T, KT and OHT. However, such oLH effects in M. albus females were slight at the early prespawning stage, and no significant signs of precocious sex reversal were found either in gonadal structure or in plasma hormones as those in postspawning treatment. After LHRH-A treatment of M. albus females in both postspawning and early prespawning stages, the gonadal structure remained "female type" with no sign of proliferation of either Leydig cells or male germ cells. The plasma levels of E2 were greatly increased after the treatment. PMID:8504919

Yeung, W S; Chen, H; Chan, S T

1993-04-01

151

Influence of sex steroids on the viability and CD11b, CD18 and CD47 expression of blood neutrophils from dairy cows in the last month of gestation  

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In the period around parturition, cows experience an increased susceptibility for the development of Escherichia coli mastitis. This increased susceptibility has been correlated with a decreased functionality of neutrophils. In the current study, it is suggested that the decreased neutrophil functionality may be induced by the extensive alterations in sex steroid levels occurring around parturition. It was first hypothesized that 17$\\beta$-estradiol and progesterone influence the viability, a...

Lamote, Inge; Meyer, Evelyne; Ketelaere, Adelheid; Duchateau, Luc; Burvenich, Christian

2006-01-01

152

NCI: SBIR & STTR - Past Funding Opportunities - Contracts - 230 Synthesis of Stable Isotope-Labeled Steroids as Internal Standards for the Measurement of Endogenous Steroid Hormones in Biologic Samples by Liquid Chromatography - Mass Spectrometry (LC-MS)  

Science.gov (United States)

Although endogenous steroid hormones, specifically estrogens, androgens, and progestogens, are believed to play critical roles in the etiology of breast, endometrial, ovarian, prostate, and possibly other cancers, research has been limited for many years by the absence of sensitive, accurate methods for measuring the absolute concentrations of steroid hormones and their metabolites in serum, urine, and tissue. The assays routinely used by epidemiologists and clinicians have relied on radiobinding kits with poor specificity and sensitivity in biologic matrixes.

153

The effects of female sex steroids on the development of autoimmune thyroiditis in thymectomized and irradiated rats  

International Nuclear Information System (INIS)

Female PVG/c strain rats are more susceptible to induction of autoimmune thyroiditis initiated by thymectomy and irradiation (Tx-X) than similarly treated males. Pre-pubertal ovariectomy further augmented susceptibility. Administration of oestrogen or progesterone to groups of 4 weeks old ovariectomized Tx-X animals over a period of 15 weeks significantly altered induction of this condition. Oestrogen administered repeatedly at dose levels of 1 ?g and 10 ?g/100 g body weight resulted in partial suppression of thyroiditis with a corresponding change in the incidence of antibodies to thyroglobulin. Oestrogen administered by a single implantation had a suppressive effect on the development of autoimmunity in ovariectomized Tx-X females. Oestrogen given by either of these procedures also reduced the incidence of thyroiditis and autoantibody induction in orchidectomized male Tx-X rats. In contrast, repeated administration of progesterone at a dose of 250 mg and 1,500 ?g/100 g body weight appeared to augment levels of autoimmunity. It is concluded that the differential susceptibility to the induction of autoimmunity by thymectomy and irradiation is the direct consequence of sex hormonal influences. The higher incidence of the disease in the female would appear to be determined by the balance between the activity of oestrogen and progesterone which would further appear to have antagonistic influences in this particular situation. (UK))

154

Anabolic Steroids  

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... Facts Anabolic Steroids Bath Salts Cocaine Cough and Cold Medicine (DXM and Codeine Syrup) Heroin Inhalants Marijuana MDMA ( ... Facts Anabolic Steroids Bath Salts Cocaine Cough and Cold Medicine (DXM and Codeine Syrup) Heroin Inhalants Marijuana MDMA ( ...

155

ALTERED SERUM SEX STEROIDS AND VITELLOGENIN INDUCTION IN WALLEYE (STIZOSTEDION VITREUM) COLLECTED NEAR A METROPOLITAN SEWAGE TREATMENT PLANT  

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Feral, male walleye collected from the Mississippi River below the St. Paul metropolitan sewage treatment plant (STP) contained measurable levels of the estrogen-inducible, female egg protein, vitellogenin. These same fish showed significantly decreased serum androgen and signifi...

156

Elevated levels of gonadotrophins but not sex steroids are associated with musculoskeletal pain in middle-aged and older European men  

Science.gov (United States)

The aim of this study was to determine the association of hormone levels with the occurrence of musculoskeletal pain. Men ages 40 to 79 years were recruited from population registers in 8 European centres. Subjects were asked to complete a postal questionnaire, which enquired about lifestyle and the occurrence of musculoskeletal pain over the past month. Total testosterone (T), oestradiol (E2), luteinising hormone (LH), and follicle-stimulating hormone (FSH) were assayed from a fasting blood sample. The association between pain status and hormone levels was assessed using multinomial logistic regression with results expressed as relative risk ratios (RRR) and 95% confidence intervals (CI). A total of 3206 men had complete data on pain status. Of these, 8.7% reported chronic widespread pain (CWP), whereas 50% had some pain although not CWP and were classified as having some pain. T and E2 were not associated with musculoskeletal pain, whereas significant differences in LH and FSH levels were found between pain groups. After adjustment for age and other possible confounders, the association between pain status and both LH and FSH persisted. Compared with those in the lowest tertile of LH, those in the highest tertile were more likely to report some pain (vs no pain, RRR = 1.28; 95% CI 1.09 to 1.50) and also CWP (vs no pain, RRR = 1.51; 95% CI 1.10 to 2.07). Similar results were found for FSH. Gonadotrophins, but not sex steroid hormone levels, are associated with musculoskeletal pain in men. Higher levels of gonadotrophins but not androgens were significantly associated with musculoskeletal pain in men. Alterations in hypothalamic–pituitary–testicular feedback mechanisms may play a role in the onset of chronic widespread pain. PMID:21421286

Tajar, Abdelouahid; McBeth, John; Lee, David M.; Macfarlane, Gary J.; Huhtaniemi, Ilpo T.; Finn, Joseph D.; Bartfai, Gyorgy; Boonen, Steven; Casanueva, Felipe F.; Forti, Gianni; Giwercman, Aleksander; Han, Thang S.; Kula, Krzysztof; Labrie, Fernand; Lean, Michael E.J.; Pendleton, Neil; Punab, Margus; Silman, Alan J.; Vanderschueren, Dirk; O’Neill, Terence W.; Wu, Frederick C.W.

2011-01-01

157

Validity of a Scale to Measure Teachers' Attitudes towards Sex Education  

Science.gov (United States)

Despite the current legislation requiring sex education as part of the school curriculum in Portugal, great obstacles to its implementation remain. Furthermore, sex education is far from being systematically administered. Thus, the main interest in our project was to validate a scale that measures teachers' attitudes towards sex education. There…

de Almeida Reis, Maria Helena; Vilar, Duarte Goncalo Rei

2006-01-01

158

General Methods for the Extraction, Purification, and Measurement of Steroids by Chromatography and Mass Spectrometry  

Science.gov (United States)

Steroids consist of an essentially lipophilic (or hydrophobic, non-polar) cyclopentanoperhydrophenanthrene nucleus modified on the periphery of the nucleus or on the side chain by the addition of hydrophilic (or lipophobic, polar) groups. Although steroids are widely distributed in nature and many thousands have been synthesised in the laboratories of pharmaceutical and chemical organisations, this chapter concentrates primarily on the methodology for the analysis of steroids of biological importance to human subjects and in particular on the methods for the analysis of the very low concentrations of steroids found in human biological tissues or formed during in vitro or in vivo studies. This does not, however, imply that the techniques discussed here may not find applicability in other areas of steroid analysis. This chapter neither discusses specifically the saturation analysis techniques including immunoassay-radioimmunoassay (RIA), enzymeimmunoassay (EIA), which are explained in Chapter 4, nor the analysis of cardenolides, sapogenins, alkaloids, brassinosteroids or ecdysteroids, which present their own analytical challenges but are of less interest in a clinical context. Further details on basic principles of mass spectrometry (MS) are discussed in Chapter 2.

Makin, Hugh L. J.; Honour, John W.; Shackleton, Cedric H. L.; Griffiths, William J.

159

Steroidal Saponins  

Science.gov (United States)

The medicinal activities of plants are generally due to the secondary metabolites (1) which often occur as glycosides of steroids, terpenoids, phenols etc. Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution. The cardiac glycosides also possess this, property but are classified separately because of their specific biological activity. Unlike the cardiac glycosides, saponins generally do not affect the heart. These are classified as steroid or triterpenoid saponins depending on the nature of the aglycone. Steroidal glycosides are naturally occurring sugar conjugates of C27 steroidal compounds. The aglycone of a steroid saponin is usually a spirostanol or a furostanol. The glycone parts of these compounds are mostly oligosaccharides, arranged either in a linear or branched fashion, attached to hydroxyl groups through an acetal linkage (2, 3). Another class of saponins, the basic steroid saponins, contain nitrogen analogues of steroid sapogenins as aglycones.

Sahu, N. P.; Banerjee, S.; Mondal, N. B.; Mandal, D.

160

Extracellular and intracellular steroid binding proteins  

International Nuclear Information System (INIS)

Steroid hormone binding proteins can be measured, after the removal of endogenous steroids, as specific complexes with radio-labelled hormones. In this study all the requirements for a quantitative determination of steroid hormone binding proteins are defined. For different methods, agargel electrophoresis, density gradient centrifugation, equilibrium dialysis and polyacrylamide electrophoresis have been evaluated. Agar electrophoresis at low temperature was found to be the simplest and most useful procedure. With this method the dissociation rates of high affinity complexes can be assessed and absolute binding protein concentrations can be determined. The dissociation rates of the oestradiol-oestrogen receptor complex and the R-5020-progestin receptor complex are low (1-2% per h run time.) In contrast, that of complexes between androgen receptor and dihydrotestosterone (17?-hydroxy-5?-androstan-3-one (DHT), progestin receptor and progesterone, corticosteroid binding globulin (CBG) and cortisol or progesterone and sex hormone binding globulin (SHBG) and DHT were hign (16-27% per h run time). Target tissue extracts (cytosols) contain, besides soluble tissue proteins, large amounts of plasma proteins. The extent of this plasma contamination can be determined by measuring the albumin concentration in cytosols by immunodiffusion. In cytosols of 4 different human target tissues the albumin content varied from 20-30% corresponding to an even higher whole plasma concentrato an even higher whole plasma concentration. Steroid binding plasma proteins, such as CBG and SHBG are constituents of this containment. (author)

 
 
 
 
161

MR measurement of normal corpus callosum: Age and sex differentiation  

International Nuclear Information System (INIS)

Measurement of various portions of the corpus callosum was performed on magnetic resonance(MR) images of 114 subjects with no known or suspected corpus callosal disorders. Midsagittal T1-weighted images used for measurements and mean diameters of various portions in each age and sex group were obtained. Measures of five portions were made: (A) the anterio-posterior length, (B) the diameter of genu position, (C) the diameter of splenium, (D) the diameter of mid-body portion, (E) the diameter of a narrow portion at the body of corpus callosum. The mean diameter in each gender group for A, B, C, D and E were 68.8 mm, 12.1 mm, 12.3 mm, 6,9 mm, 4.1 mm in male and 69.9 mm, 12.0 mm, 12.1 mm, 6.4 mm, 4.1 mm in female, retrospectively. The groups of 0-9 years of both genders showed the minimum mean value in each portion

162

MR measurement of normal corpus callosum: Age and sex differentiation  

Energy Technology Data Exchange (ETDEWEB)

Measurement of various portions of the corpus callosum was performed on magnetic resonance(MR) images of 114 subjects with no known or suspected corpus callosal disorders. Midsagittal T1-weighted images used for measurements and mean diameters of various portions in each age and sex group were obtained. Measures of five portions were made: (A) the anterio-posterior length, (B) the diameter of genu position, (C) the diameter of splenium, (D) the diameter of mid-body portion, (E) the diameter of a narrow portion at the body of corpus callosum. The mean diameter in each gender group for A, B, C, D and E were 68.8 mm, 12.1 mm, 12.3 mm, 6,9 mm, 4.1 mm in male and 69.9 mm, 12.0 mm, 12.1 mm, 6.4 mm, 4.1 mm in female, retrospectively. The groups of 0-9 years of both genders showed the minimum mean value in each portion.

Lee, Myung Seob; Kim, Myung Soon; Park, Hyun Ju [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

1992-07-15

163

Epidermal growth factor receptor in breast cancer: storage conditions affecting measurement, and relationship to steroid receptors.  

Science.gov (United States)

This study investigates the effect of freezing and storage of tissue and subcellular fractions on the measurement of epidermal growth factor receptors (EGF-r); compares competition binding and single saturating dose assays (SSD) for quantitating EGF-r levels; investigates several tissues as potential quality control; and examines the relationship between EGF-r and hormone receptor expression in human breast cancers. Mouse and calf uterine cell membranes were preferred sources of quality control tissue with similar levels of high affinity EGF-r to human breast cancer tissue (less than 150-200 fmol/mg membrane protein). Studies using pooled mouse uterine tissues indicated a loss of 40% in EGF-r activity following a single-20 degrees C freeze/thaw cycle, while a breast cancer tissue showed a 75% loss, independent of storage temperature (liquid nitrogen, -70 degrees C, -20 degrees C). A single freeze/thaw cycle of mouse uterine broken cell pellets (nuclei plus membrane fraction) again indicated a loss of EGF-r irrespective of storage temperature (43% loss at -70 degrees C, 52% loss at -20 degrees C). In most cases irrespective of the tissue type or tissue fraction being stored, the length of storage had little impact on the extent of the loss in activity. A second freeze/thaw cycle of intact tissue, or freezing of broken cell pellets from a previously-frozen tissue, led to a further major or total loss of the remaining EGF-r. Overall these results are commensurate with the published effects of freezing and storage on estrogen receptor measurement. In addition, our studies suggest that the most suitable procedure for assaying frozen breast cancer specimens for EGF-r levels in conjunction with steroid receptor quantitation is to prepare and assay both cytosol and membrane fractions for their respective receptor content without further storage. A concordance of 86% was found in 44 breast cancers assayed for EGF-4 by saturation analysis and SSD. Statistically significant inverse relationships were found between EGF-r and estrogen and progesterone receptor levels in the study of approximately 350 breast cancer patients. No association was found with tumor stage or diameter, axillary node involvement, or patient age. PMID:1391979

McLeay, W R; Horsfall, D J; Seshadri, R; Morrison, D A; Saccone, G T

1992-01-01

164

2,3,7,8-Tetrachlorodibenzo-p-dioxin activates the aryl hydrocarbon receptor and alters sex steroid hormone secretion without affecting growth of mouse antral follicles in vitro  

International Nuclear Information System (INIS)

The persistent environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an ovarian toxicant. These studies were designed to characterize the actions of TCDD on steroidogenesis and growth of intact mouse antral follicles in vitro. Specifically, these studies tested the hypothesis that TCDD exposure leads to decreased sex hormone production/secretion by antral follicles as well as decreased growth of antral follicles in vitro. Since TCDD acts through binding to the aryl hydrocarbon receptor (AHR), and the AHR has been identified as an important factor in ovarian function, we also conducted experiments to confirm the presence and activation of the AHR in our tissue culture system. To do so, we exposed mouse antral follicles for 96 h to a series of TCDD doses previously shown to have effects on ovarian tissues and cells in culture, which also encompass environmentally relevant and pharmacological exposures (0.1–100 nM), to determine a dose response for TCDD in our culture system for growth, hormone production, and expression of the Ahr and Cyp1b1. The results indicate that TCDD decreases progesterone, androstenedione, testosterone, and estradiol levels in a non-monotonic dose response manner without altering growth of antral follicles. The addition of pregnenolone substrate (10 ?M) restores hormone levels to control levels. Additionally, Cyp1b1 levels were increased by 3–4 fold regardless of the dose of TCDD exposure, evidence of AHR activation. Overall, these data indicate that TCDD may act prior to pregnenolone formation and through AHR transcriptional control of Cyp1b1, leading to decreased hormone levels without affecting growth of antral follicles. -- Highlights: ?TCDD disrupts sex steroid hormone levels, but not growth of antral follicles. ?Pregnenolone co-treatment by-passes TCDD-induced steroid hormone disruption. ?TCDD affects steroid hormone levels through an AHR pathway in antral follicles.

165

Endocrine assessment of impotence--pitfalls of measuring serum testosterone without sex-hormone-binding globulin.  

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The pitfalls of measuring only total serum testosterone are illustrated by a 52 year old man whose hyperprolactinaemia was associated with normal total serum testosterone but a raised sex-hormone-binding globulin, giving a low free testosterone. Prolactin suppression with bromocriptine normalized sex-hormone-binding globulin and free testosterone, and restored potency and energy after 30 years of impotence and tiredness.

Hardy, K. J.; Seckl, J. R.

1994-01-01

166

Brain nonapeptide and gonadal steroid responses to deprivation of heterosexual contact in the black molly.  

Science.gov (United States)

Fish may respond to different social situations with changes in both physiology and behaviour. A unique feature of fish is that social interactions between males and females strongly affect the sexual characteristics of individuals. Here we provide the first insight into the endocrine background of two phenomena that occur in mono-sex groups of the black molly (Poecilia sphenops): masculinization in females and same-sex sexual behaviour, manifested by gonopodial displays towards same-sex tank mates and copulation attempts in males. In socially controlled situations, brain neurohormones impact phenotypic sex determination and sexual behaviour. Among these hormones are the nonapeptides arginine vasotocin (AVT) and isotocin (IT), counterparts of the well-known mammalian arginine vasopressin and oxytocin, respectively. To reveal potential hormone interactions, we measured the concentrations of bioactive AVT and IT in the brain, along with those of the sex steroids 17?-estradiol and 11-ketotestosterone in the gonads, of females, masculinized females, males displaying same-sex sexual behaviour and those who did not. These data were supplemented by morphological and histological analyses of the gonads. Correlations between brain nonapeptides and gonadal steroids strongly suggest a cross talk between hormonal systems. In the black molly, the masculinization process was associated with the production of brain AVT and gonadal steroids, whereas same-sex sexual behaviour involves both brain nonapeptides, but neither of the sex steroids. This study extends current knowledge of endocrine control of phenotypic sex and sexual behaviour in fish and for the first time links brain nonapeptides with the occurrence of male-male sexual behaviour in lower vertebrates. PMID:25527645

Kulczykowska, Ewa; Kalamarz-Kubiak, Hanna; Nietrzeba, Marta; Gozdowska, Magdalena

2014-01-01

167

Steroid radioimmunoassays  

International Nuclear Information System (INIS)

An estrogen radioimmunoassay was used to study the problem of blanks in steroid assays. Negligible binding (1.5 percent) in the non-antibody tubes prevailed throughout the study. The assay was validated using accepted procedures. Both water and solvent blanks had estrogen concentrations of 7-9 pg/tube. However, neither water nor solvent blanks showed a dose-related response, indicating that they were 'real' blanks. Exogenous estradiol, when added to water and solvent in quantities less than the estimated blank, was not quantitatively recovered. However, exogenous estradiol added to the water solvent in quantities greater than the blank estimate was quantitatively recovered. The sensitivity of the reference standard curve was 6-10 pg/tube, approximately the same as the blank estimate. These results indicated that the estimates of water and solvent blanks were measures of the assay sensitivity. In such circumstances, it is suggested that blank estimates should not be subtracted from sample values. If the blank estimates are high, attention should be directed towards improving the sensitivity of the assay

168

Extensive esterification of adrenal C19-delta 5-sex steroids to long-chain fatty acids in the ZR-75-1 human breast cancer cell line  

Energy Technology Data Exchange (ETDEWEB)

Estrogen-sensitive human breast cancer cells (ZR-75-1) were incubated with the 3H-labeled adrenal C19-delta 5-steroids dehydroepiandrosterone (DHEA) and its fully estrogenic derivative, androst-5-ene-3 beta,17 beta-diol (delta 5-diol) for various time intervals. When fractionated by solvent partition, Sephadex LH-20 column chromatography and silica gel TLC, the labeled cell components were largely present (40-75%) in three highly nonpolar, lipoidal fractions. Mild alkaline hydrolysis of these lipoidal derivatives yielded either free 3H-labeled DHEA or delta 5-diol. The three lipoidal fractions cochromatographed with the synthetic DHEA 3 beta-esters, delta 5-diol 3 beta (or 17 beta)-monoesters and delta 5-diol 3 beta,17 beta-diesters of long-chain fatty acids. DHEA and delta 5-diol were mainly esterified to saturated and mono-unsaturated fatty acids. For delta 5-diol, the preferred site of esterification of the fatty acids is the 3 beta-position while some esterification also takes place at the 17 beta-position. Time course studies show that ZR-75-1 cells accumulate delta 5-diol mostly (greater than 95%) as fatty acid mono- and diesters while DHEA is converted to delta 5-diol essentially as the esterified form. Furthermore, while free C19-delta 5-steroids rapidly diffuse out of the cells after removal of the precursor (3H)delta 5-diol, the fatty acid ester derivatives are progressively hydrolyzed, and DHEA and delta 5-diol thus formed are then sulfurylated prior to their release into the culture medium. The latter process however is rate-limited, since new steady-state levels of free steroids and fatty acid esters are rapidly reached and maintained for extended periods of time after removal of precursor, thus maintaining minimal concentrations of intracellular steroids.

Poulin, R.; Poirier, D.; Merand, Y.; Theriault, C.; Belanger, A.; Labrie, F.

1989-06-05

169

Local synthesis and effect of sex steroids in human skin and the hair follicle and hormonal effects on the wound healing response  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Humans, as others mammals, are able to synthesize steroid hormones from endocrine organs, such as gonads, adrenal gland and placenta. The expression and activity of steroidogenic enzymes in peripheral tissues provide the intracrine production of active androgens and estrogens by transformation of adrenal precursor dehydroepiandrosterone (DHEA). Only human and primates are unique in having large amounts of the inactive adrenal DHEA and especially DHEA-sulfate (DHEA-S). However, adrenal secreti...

Pomari, Elena

2011-01-01

170

Extensive esterification of adrenal C19-delta 5-sex steroids to long-chain fatty acids in the ZR-75-1 human breast cancer cell line  

International Nuclear Information System (INIS)

Estrogen-sensitive human breast cancer cells (ZR-75-1) were incubated with the 3H-labeled adrenal C19-delta 5-steroids dehydroepiandrosterone (DHEA) and its fully estrogenic derivative, androst-5-ene-3 beta,17 beta-diol (delta 5-diol) for various time intervals. When fractionated by solvent partition, Sephadex LH-20 column chromatography and silica gel TLC, the labeled cell components were largely present (40-75%) in three highly nonpolar, lipoidal fractions. Mild alkaline hydrolysis of these lipoidal derivatives yielded either free 3H-labeled DHEA or delta 5-diol. The three lipoidal fractions cochromatographed with the synthetic DHEA 3 beta-esters, delta 5-diol 3 beta (or 17 beta)-monoesters and delta 5-diol 3 beta,17 beta-diesters of long-chain fatty acids. DHEA and delta 5-diol were mainly esterified to saturated and mono-unsaturated fatty acids. For delta 5-diol, the preferred site of esterification of the fatty acids is the 3 beta-position while some esterification also takes place at the 17 beta-position. Time course studies show that ZR-75-1 cells accumulate delta 5-diol mostly (greater than 95%) as fatty acid mono- and diesters while DHEA is converted to delta 5-diol essentially as the esterified form. Furthermore, while free C19-delta 5-steroids rapidly diffuse out of the cells after removal of the precursor [3H]delta 5-diol, the fatty acid ester derivatives are progressively hydrolyzed, and DHEA and delta 5-diol thus formed are then sulfurylated prior to the formed are then sulfurylated prior to their release into the culture medium. The latter process however is rate-limited, since new steady-state levels of free steroids and fatty acid esters are rapidly reached and maintained for extended periods of time after removal of precursor, thus maintaining minimal concentrations of intracellular steroids

171

Physical activity, sex steroid, and growth factor concentrations in pre- and post-menopausal women: a cross-sectional study within the EPIC cohort  

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Purpose: Increased physical activity (PA) is associated with a reduced risk of several cancers. PA may reduce cancer risk by changing endogenous hormones levels, but relatively little research has focused on this topic. The purpose of this study was to elucidate the relation between PA and endogenous hormone concentrations. Methods: A cross-sectional analysis of 798 pre- and 1,360 post-menopausal women included as controls in case-control studies on endogenous hormones (steroids, progesterone...

Rinaldi, S; Kaaks, R.; Friedenreich, Cm; Key, Tj; Travis, R.; Biessy, C.; Slimani, N.; Overvad, K.; Østergaard, Jn; Tjønneland, A.; Olsen, A.; Mesrine, S.; Fournier, A.; Dossus, L.; Lukanova, A.

2014-01-01

172

Reliability criteria for steroid radioimmunoassay  

International Nuclear Information System (INIS)

The principle of radioimmunoassay has been applied to every hormonal steroid and many steroids without known biological activity. The validation of steroid radioimmunoassay requires the evaluation of reliability criteria. These criteria involve the degree of relative specificity of the assay, the sensitivity which dictates the volume of biological fluid required for accurate and precise measurement, and the precision and accuracy of the assay which should be evaluated in every batch of assays as quality control. The use of steroid radioimmunoassay in physiological and clinical studies requires prior validation of these assays by proper evaluation of the reliability criteria

173

Regulation of reproduction- and biomarker-related gene expression by sex steroids in the livers and ovaries of adult female western mosquitofish (Gambusia affinis).  

Science.gov (United States)

To assess the adverse toxicological effects of steroid hormones on western mosquitofish (Gambusia affinis), 180 adult females were exposed to individual or binary combinations of progesterone (1?g/L), testosterone (1?g/L) and 17?-estradiol (1?g/L) for eight days. The expression patterns of vitellogenin, estrogen receptor, androgen receptor, metallothionein, and cytochrome P450 1A genes in mosquitofish varied according to tissue as well as the specificity of steroids. Treatment by progesterone or testosterone alone inhibited target gene expression in the livers. The expression levels of both vitellogenin A and vitellogenin B mRNAs were up-regulated by17?-estradiol, and a parallel induction of estrogen receptor ? mRNA expression was also observed in the livers. In addition, 17?-estradiol treatment alone suppressed androgen receptor ?, metallothionein and cytochrome P450 1A mRNA expression in the livers. In general, multiple hormone treatments had different effects on target gene expression compared with corresponding hormone alone. The results demonstrate that steroid hormones cause multiple biological responses including the expression of vitellogenin, estrogen receptor and androgen receptor mRNA in the hormone signaling pathways and the expression of metallothionein and cytochrome P450 1A mRNA in the xenobiotic signaling pathway. PMID:22353216

Huang, Guo-Yong; Ying, Guang-Guo; Liu, Shan; Fang, Yi-Xiang

2012-05-01

174

Regulation of 3?-hydroxysteroid dehydrogenase and sulphotransferase 2A1 gene expression in primary porcine hepatocytes by selected sex-steroids and plant secondary metabolites from chicory (Cichorium intybus L.) and wormwood (Artemisia sp.).  

Science.gov (United States)

In pigs the endogenously produced compound androstenone is metabolised in the liver in two steps by 3?-hydroxysteroid dehydrogenase (3?-HSD) and sulphotransferase 2A1 (SULT2A1). The present study investigated the effect of selected sex-steroids (0.01-1 ?M androstenone, testosterone and estradiol), skatole (1-100 ?M) and secondary plant metabolites (1-100 ?M) on the expression of 3?-HSD and SULT2A1 mRNA. Additionally the effect of a global methanolic extract of dried chicory root was investigated and compared to previous obtained in vivo effects. Primary hepatocytes were isolated from the livers of piglets (crossbreed: Landrace×Yorkshire and Duroc) and cultured for 24h before treatment for an additionally 24h. RNA was isolated from the hepatocytes and specific gene expression determined by RT-PCR using TaqMan probes. The investigated sex-steroids had no effect on the mRNA expression of 3?-HSD and SULT2A1, while skatole decreased the content of SULT2A1 30% compared to control. Of the investigated secondary plant metabolites artemisinin and scoparone (found in Artemisia sp.) lowered the content of SULT2A1 by 20 and 30% compared to control, respectively. Moreover, we tested three secondary plant metabolites (lactucin, esculetin and esculin) found in chicory root. Lactucin increased the mRNA content of both 3?-HSD and SULT2A1 by 200% compared to control. An extract of chicory root was shown to decrease the expression of both 3?-HSD and SULT2A1. It is concluded that the gene expression of enzymes with importance for androstenone metabolism is regulated by secondary plant metabolites in a complex manner. PMID:24333270

Rasmussen, Martin Krøyer; Ekstrand, Bo

2014-02-15

175

Steroids (For Parents)  

Science.gov (United States)

... your child isn't at risk. What Are Steroids? Drugs commonly referred to as "steroids" are classified ... number of health problems. Continue How Do Anabolic Steroids Work? Anabolic steroids are drugs that resemble the ...

176

Multivariate misgivings: is D a valid measure of group and sex differences?  

Science.gov (United States)

In the study of group and sex differences in multivariate domains such as personality and aggression, univariate effect sizes may underestimate the extent to which groups differ from one another. When multivariate effect sizes such as Mahalanobis D are employed, sex differences are often found to be considerably larger than commonly assumed. In this paper, I review and discuss recent criticism concerning the validity of D as an effect size in psychological research. I conclude that the main arguments against D are incorrect, logically inconsistent, or easily answered on methodological grounds. When correctly employed and interpreted, D provides a valid, convenient measure of group and sex differences in multivariate domains. PMID:24333840

Del Giudice, Marco

2013-01-01

177

Sexual size dimorphism and sex determination by morphometric measurements in the Coscoroba Swan  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The accuracy of morphological sexing and the occurrence of sexual dimorphism were analyzed in mature and immature Coscoroba Swans (Coscoroba coscoroba, Anatidae) near the Estação Ecológica do Taim, southern Brazil. On the basis of weight and 10 linear measurements of external morphology, multivariate analysis of vari- ance showed that males were consistently larger than females (sex confirmed via genetic markers) and mature birds were consistently larger than immatures. Ove...

Calabuig, Cecilia P.; Green, Andy J.; Ferrer, Miguel; Muriel, Roberto; Moreira, Heden

2011-01-01

178

Are there sex differences in Fetal Abdominal Subcutaneous Tissue (FAST) measurements?  

LENUS (Irish Health Repository)

OBJECTIVE: To determine if Fetal Abdominal Subcutaneous Tissue (FAST) measurements using antenatal ultrasound differ between male and female fetuses. STUDY DESIGN: Women who had an ultrasound examination for fetal growth between 20 and 40 weeks gestation were studied. Women with diabetes mellitus were excluded. The fetal anterior abdominal subcutaneous tissue was measured on the anterior abdominal wall in millimetres anterior to the margins of the ribs, using magnification at the level of the abdominal circumference. The fetal sex was recorded after delivery. RESULTS: A total of 557 fetuses were measured, 290 male and 267 female. The FAST measurements increased with gestational age. The FAST increased at the same rate for both male and female fetuses and at any given week there was no sex difference. CONCLUSIONS: The increased fat composition in females reported after birth was not found in abdominal wall subcutaneous fat measurements using ultrasound during pregnancy. Antenatal centile charts for FAST do not need to be based on sex.

Farah, Nadine

2012-02-01

179

Evaluation of the accuracy of different molar teeth measurements in assessing sex.  

Science.gov (United States)

Teeth are considered to be a very useful tissue for sex determination and molars are among the most dimorphic teeth. Even though mesiodistal (MD) and buccolingual (BL) crown diameters are usually employed for sex assessment, alternative measurements like MD and BL cervical diameters as well as crown and cervical diagonal diameters have been developed. This study explores the utility of crown and cervical MD, BL and diagonal measurements of molars in sex assessment when used separately. A total of 254 permanent molars (excluded third molars) from 101 individuals (51 males, 50 females) from the Athens Collection were examined. Stepwise discriminant analysis was used to evaluate the accuracy of each diameter group in assessing sex. It was found that the accuracy ranges from 65.5 to 88.4 %. Cervical diagonal diameters are the most accurate followed by crown diagonal diameters, and crown and cervical MD and BL diameters. Therefore the high classification accuracy of diagonal diameters show that these measurements are more reliable for sex determination than the traditional MD and BL and can be considered a promising method for sex assessment from human teeth. PMID:22926774

Zorba, Eleni; Spiliopoulou, Chara; Moraitis, Konstantinos

2013-03-01

180

Sex assessment using clavicle measurements: inter- and intra-population comparisons.  

Science.gov (United States)

We studied sexual dimorphism of the human clavicle in order to describe size variation and create population-specific discriminant tools for morphometric sex assessment. The studied sample consisted of 200 skeletons of adult individuals obtained from the University of Athens Human Skeletal Reference Collection, Athens, Greece. The specimens were well-documented and represented a modern population from cemeteries in the Athens area. Six dimensions typically used for clavicle measurements were recorded. For sexing clavicles, we used both traditional univariate (limiting, demarking and sectioning points) and multivariate discriminant function analysis. The accuracy of the best five classification equations/functions ranged from 91.62% to 92.55% of correctly assigned specimens. By testing new and previously published sexing functions (Greeks, Polynesians, Guatemalans) on four available population samples (English, Indians from Amritsar, Indians from Varanasi, and data from the present study) we found that, for some combinations of tested and reference samples, the accuracy of the sex assessment may decrease even below the probability given by random sex assignment. Therefore, measurements of the clavicle should not be used for sex assessment of individual cases (both forensic and archeological) whose population origin is unknown. However, significant metric differences were also recorded among three different Greek samples (i.e. within a population). As a consequence, application of a sexing method generated from one Greek sample and applied to another Greek sample led to negligible reduction in the success of sex assessment, despite general similarities in ethnic origin (Greeks), generation structure and presumed social background of the samples. Therefore, we believe that future studies should focus on understanding the nature of the differences among within-population reference samples. PMID:24075622

Králík, Miroslav; Urbanová, Petra; Wagenknechtová, Martina

2014-01-01

 
 
 
 
181

Even Highly Correlated Measures Can Add Incrementally to Predicting Recidivism among Sex Offenders  

Science.gov (United States)

Criterion-referenced measures, such as those used in the assessment of crime and violence, prioritize predictive accuracy (discrimination) at the expense of construct validity. In this article, we compared the discrimination and incremental validity of three commonly used criterion-referenced measures for sex offenders (Rapid Risk Assessment for…

Babchishin, Kelly M.; Hanson, R. Karl; Helmus, Leslie

2012-01-01

182

Immunoradiometric measurement of pS2 in breast cancer. Correlation with steroid receptors and plasminogen activators  

Energy Technology Data Exchange (ETDEWEB)

pS2 was measured by radioimmunometric assay in tumour extracts from 197 breast cancer patients. Values ranged from 0 to 50 ng/mg protein (mean 9.6 and median 3 ng/mg). We found no correlation with age, menopausal status, nodal metastases, disease stage of tumour histology. There was, however, a linear relationship with both ER (p<0.0001) (particularly nuclear ER) and PR (p<0.0001) expression determined by enzyme immunoassay (ELISA), as well as a good correlation when high and low expressors were stratified on the basis of combined ER/PR expression using consensus cut-off points. Only 15% of ER-ve/PR-ve patients were classified as pS2+ve compared with 83% of those who were ER+ve/PR+ve. pS2 was also directly correlated with high expression of tPA and inversely with uPA. Comparison with previous studies showed that the current ELISA method produced consistent results, in contrast to other methods, particularly those based on immunohistochemical detection. The close relationship between pS2 and both steroid receptors suggests that pS2 may be important in terms of defining hormone-responsive patients who are likely to benefit from endocrine therapy. (orig.)

Luqmani, Y. [Kuwait Univ. (Kuwait). Faculty of Allied Health Sciences; Kuwait Cancer Control Center (Kuwait); Temmim, L.; Memon, A. [Kuwait Univ. (Kuwait). Faculty of Medicine; Parkar, A.; Ali, M.; Motawy, M.; Baker, H

1999-07-01

183

Radioimmunoassay of steroid hormone  

International Nuclear Information System (INIS)

Low acid pepsin treated gamma-globulin was applied to ammonium sulfate salting out method, which was a method to separate bound fraction from free one in radioimmunoassay of steroid hormone, and the effect of the separation and the standard curve were examined. Pepsin treated gamma-globulin was prepared in pH 1.5 to 5.5 and then the pepsin was completely removed. It had an effect to accelerate the precipitation in radioimmunoassay of steroid hormone labelled with 3H. The effect of pepsin treated gamma-globulin to adhere free steroid hormone and to slat out bound one was compared with that of human gamma-globulin. Pepsin treated gamma-globulin, which was water soluble, could easier reach its optimal concentration, and the separation effect was better than human gamma-globulin. The standard curve of it was steeper, particularly in a small dose, and the reproducibility was also better. It could be applied not only to aldosterone and DOC, but also to the steroid hormones, such as progesterone and DHEA, and it seemed suitable for routine measurement method. (Kanao, N.)

184

Measurement of Serum Leptin Concentrations in University Undergraduates by Competitive Elisa Reveals Correlations With Body Mass Index and Sex  

Science.gov (United States)

Synthesized mainly in adipocytes, leptin is a peptide hormone that plays a key role in the regulation of body weight and composition. The serum leptin concentrations of 193 Singapore university medical and bioscience undergraduates aged 19ÃÂ26 yr were measured using a competitive ELISA kit, and their leptin levels were correlated with sex and body mass index (BMI). Mean leptin levels were more than twice as high in females than in males of corresponding weight status, especially among females of healthy weight who exhibited levels that were 5.7 times higher. Overweight individuals generally demonstrated higher circulating leptin concentrations than healthy-weight and underweight participants. The differences in mean leptin levels between underweight and overweight males (P = 0.006), as well as between healthy-weight and overweight males (P = 0.011) were statistically significant. Comparison tests of leptin levels between healthy-weight and underweight females were highly significant (P = 0.001). Highly significant linear correlations between BMI and the logarithm of leptin concentration were observed in the female (r = 0.44) and male (r = 0.36) groups. These results reiterate the impact of gonadal steroids as mediators of the apparent sexual dimorphism in circulating leptin. The findings also corroborate evidence that adiposity determines leptin levels. This laboratory exercise has educational value for undergraduates by determining their BMIs, by alluding to the importance of maintaining healthy body composition, and by emphasizing the molecular mechanisms of body weight regulation and obesity, with special reference to leptin. This practical study also exemplifies the principles and applications of the competitive ELISA technique and integrates certain key concepts of physiology, molecular biology, immunology, and medicine.

Dr. Vincent T. K. Chow (National University of Singapore Faculty of Medicine Department of Microbiology); Dr. M. C. Phoon (National University of Singapore Faculty of Medicine Department of Microbiology)

2003-06-01

185

Sex differences in DHEA and estradiol during development in a wild songbird: Jugular versus brachial plasma.  

Science.gov (United States)

Sexual differentiation of the brain has traditionally been thought to be driven by gonadal hormones, particularly testosterone (T). Recent studies in songbirds and other species have indicated that non-gonadal sex steroids may also be important. For example, dehydroepiandrosterone (DHEA)--a sex steroid precursor that can be synthesized in the adrenal glands and/or brain--can be converted into active sex steroids, such as 17beta-estradiol (E(2)), within the brain. Here, we examine plasma DHEA and E(2) levels in wild developing European starlings (Sturnus vulgaris), from hatch (P0) to fledging (P20). Blood samples were collected from either the brachial vein (n=143) or the jugular vein (n=129). In songbirds, jugular plasma is enriched with neurally-synthesized steroids and, therefore, jugular plasma is an indirect measure of the neural steroidal milieu. Interestingly, brachial DHEA levels were higher in males than females at P4. In contrast, jugular DHEA levels were higher in females than males at P0 and P10. Brachial E(2) levels were higher in males than females at P6. Surprisingly, jugular E(2) levels were not high and showed no sex differences. Also, we calculated the difference between brachial and jugular steroid levels. At several ages, jugular steroid levels were lower than brachial levels, particularly in males, suggesting greater neural metabolism of circulating DHEA and E(2) in males than females. At a few ages, jugular steroid levels were higher than brachial levels, suggesting neural secretion of DHEA or E(2) into the general circulation. Taken together, these data suggest that DHEA may play a role in brain sexual differentiation in songbirds. PMID:18423637

Chin, Eunice H; Shah, Amit H; Schmidt, Kim L; Sheldon, Lani D; Love, Oliver P; Soma, Kiran K

2008-06-01

186

An interlaboratory study measuring sex steroids with RIAs and/or ELISAs: Are we comparing apples to oranges?  

Science.gov (United States)

Endocrine-disrupting chemicals (EDCs) are exogenous substances released into the environment that can lead to adverse reproductive effects in fish by a number of mechanisms including altering circulating levels of estradiol (E2), testosterone (T) and 11-ketotestosterone (11KT). ...

187

Ovarian steroid hormones: what's hot in the stem cell pool?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vital role of ovarian hormones in the development of the normal breast foreshadowed their importance in mammary stem cell regulation. Two recent papers reveal that 17?-estradiol and progesterone control the size and repopulating ability of the mammary stem cell compartment. This likely occurs via paracrine signaling from steroid receptor-positive luminal cells to steroid receptor-negative stem cells. These findings illuminate roles for the female sex steroids in mobilizing the stem cell ...

Cittelly, Diana M.; Richer, Jennifer K.; Sartorius, Carol A.

2010-01-01

188

Radioimmunoassay of steroids in biological fluids. [/sup -/  

Energy Technology Data Exchange (ETDEWEB)

The principle of radioimmunoassay has been applied to many organic compounds of biological interest. One of the requirements for the application of radioimmunoassay to the measurement of a compound is that this compound must be antigenic and must elicit high affinity antibodies. Steroids when covalently linked to protein carriers behave like haptenic groups, and specific antibodies may be evoked against them by active immunization. Strong covalent bonds between the steroid and the protein are required to prevent in vivo lysis of these bonds during immunization. Peptide bonds are biologically stable. To prepare such bonds, a free carboxyl group is attached to the steroid molecule using the hydroxyl and ketone groups of the steroid molecule as anchoring points. Peptide bonds are formed between these carboxyl groups and the epsilon-amino groups of lysine residue of albumin. Some of these steroid-protein conjugates were found to be effective in producing specific antibodies against the steroid residues, and the antisera obtained have been used by many investigators, including us, as specific binding reagents in the radioimmunoassay of these steroids in biological fluids. Because of the multiplicity of closely related steroids in biological fluids, some form of chromatographic purification is usually required to obtain specificity. For some steroids with unique configuration and for synthetic steroids not normally present in biological fluids, it may be possible to perform the assay directly, without extraction and chromatography. Also, if a particular steroid exists in a particular biological fluid in relatively large concentration compared to related interfering steroids, it may be measured directly. Because of the ease of performance, radioimmunoassay lends itself to automation, and such an adaptation for the measurement of steroids ought to be forthcoming.

Abraham, G.E.

1975-01-01

189

Adolescent Steroid Use.  

Science.gov (United States)

The study focused on non-medical steroid use by adolescents according to data obtained from the National Institute on Drug Abuse, professional literature, 30 key informants knowledgeable in steroid issues, and 72 current or former steroid users. The findings indicated: (1) over 250,000 adolescents, primarily males, used or have used steroids, and…

Office of Inspector General (DHHS), Washington, DC.

190

Body growth of children with steroid-resistant nephrotic syndrome.  

Science.gov (United States)

Whilst it is assumed that body growth is retarded in children with steroid-resistant nephrotic syndrome (NS), the degree of growth failure and the pathomechanisms involved are poorly understood. We collected serial growth data in 45 children (24 males) with steroid-resistant NS usually from onset to end-stage renal disease (ESRD) during childhood (n=10) or until final height was attained (n=27). Mean follow-up time was 9 (2-19) years. Mean initial standardized height was -0.3+/-1.2 standard deviation scores (SDS). Mean final height was +0.4 SDS in males and -1.0 SDS in females (sex difference not significant). In 16 patients with serum creatinine levels consistently <1.2 mg/dl, mean final height SDS was 0.3 SDS higher than that obtained within 6 months of onset. In contrast, 9 children who entered ESRD lost an average of 1.3 SDS from the initial record to ESRD (P=0.017). In prepubertal patients without renal insufficiency, mean height SDS decreased during corticosteroid treatment by 0.3 SDS, followed by a partial catch-up after discontinuation of treatment; the change from initial to final height SDS was inversely correlated with the total prednisone dose given (r=-0.50, P=0.03). In 16 prepubertal children with serial height and serum protein measurements who were off steroids and maintained normal creatinine levels, mean individual albumin concentrations correlated with the change in height SDS per year (r=0.65, P=0.0006) and in boys with final height (r=0.73, P=0.03). In conclusion, growth in steroid-resistant NS depends on the preservation of renal function, the cumulative dose of steroids applied, and the severity of hypoproteinemia. PMID:10603130

Schärer, K; Essigmann, H C; Schaefer, F

1999-11-01

191

Identifying and Distinguishing the Impact of Steroid Hormones  

Directory of Open Access Journals (Sweden)

Full Text Available Developmental programming is gaining considerable leverage as a conceptual framework for understanding individual variability in human behavioral and somatic health. The current mini-review examines some of the key conceptual and methodological challenges for developmental programming research focused on fetal sex steroid exposure and physical, behavioral, physiological and health outcomes. Specifically, we consider the bases for focusing on sex steroids, methods for assessing prenatal steroid hormone exposure, confounding factors, and the the most relevant postnatal outcomes. We conclude with a brief consideration, based on current knowledge, of the applications of the existing research findings for practice.

ThomasGO'connor

2014-04-01

192

N-demethylation of ethylmorphine in pregnant and non-pregnant women and in men: an evaluation of the effects of sex steroids.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

1. The effects of oestrogens, testosterone, progesterone and medroxyprogesterone acetate (MPA) on the rate of N-demethylation of ethylmorphine (EM) to norethylmorphine (NEM) were studied in human adult liver microsomes. 2. N-Demethylase activity was found to be inhibited by progesterone and MPA to a similar extent while oestrogens and testosterone had no or negligible effects. 3. These findings prompted us to measure the N-demethylation of EM in relation to serum progesterone concentration in...

Gerdin, E.; Rane, A.

1992-01-01

193

Conceptualization and measurement of homosexuality in sex surveys: a critical review  

Directory of Open Access Journals (Sweden)

Full Text Available This article reviews major national population sex surveys that have asked questions about homosexuality focusing on conceptual and methodological issues, including the definitions of sex, the measured aspects of homosexuality, sampling and interviewing technique, and questionnaire design. Reported rates of major measures of same-sex attraction, behavior, partners, and sexual identity from surveys are also presented and compared. The study of homosexuality in surveys has been shaped by the research traditions and questions ranging from sexology to the epidemiology of HIV/AIDS. Sexual behavior has been a central topic at least since Kinsey. Issues of sexual attraction and/or orientation and sexual identity have emerged more recently. Differences in the treatment of men and women in the design and analysis of surveys as well as in the reported rates in different surveys, in different countries and time periods are also presented and discussed. We point out the importance of the consideration of both methodological and social change issues in assessing such differences.

Michaels Stuart

2006-01-01

194

N-demethylation of ethylmorphine in pregnant and non-pregnant women and in men: an evaluation of the effects of sex steroids.  

Science.gov (United States)

1. The effects of oestrogens, testosterone, progesterone and medroxyprogesterone acetate (MPA) on the rate of N-demethylation of ethylmorphine (EM) to norethylmorphine (NEM) were studied in human adult liver microsomes. 2. N-Demethylase activity was found to be inhibited by progesterone and MPA to a similar extent while oestrogens and testosterone had no or negligible effects. 3. These findings prompted us to measure the N-demethylation of EM in relation to serum progesterone concentration in vivo in three groups of volunteers with large physiological differences in their endogenous levels of progesterone, i.e. i) pregnant women, ii) non-pregnant ovulating women and iii) men. 4. The metabolic ratio (MRP) of EM to NEM in plasma 60 min after dosage and the corresponding ratio in urine sampled for 6 h (MRU,1), measured on two occasions 14 days apart were used to reflect intraindividual variation in the rate of N-demethylation. 5. The average difference in MRP and MRU,1 between the two occasions was similar in all groups. However, the variability in MRP between individuals within a group was significantly higher in ovulating women than in men, but this had no relation to the serum concentrations of progesterone or oestradiol. 6. The cumulative 12 h urinary excretion of EM, NEM and morphine (MO) after hydrolysis with beta-glucuronidase was about 46%. There was no difference in the metabolic ratio of EM to NEM and its conjugate(s) in the urine between the luteal and the follicular phases. Our findings suggest that the menstrual cycle does not influence the rate of N-demethylation of EM. PMID:1389949

Gerdin, E; Rane, A

1992-01-01

195

Steroid profiling and confirmation of the T/E - ratio in doping control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Anabolic-androgenic steroids are naturally occurring or synthetic derivates of male sex hormones. All anabolic-androgenic steroids are prohibited by the World Anti-Doping Agency because of their muscle growth stimulating effect. At the Seibersdorf Doping-Control Laboratory, urine samples from athletes are first screened with a screen testing procedure to obtain an endogenous steroid profile, in order to identify samples suspected of containing endogenous steroids of exogenous origin. This i...

Hanssen, Kine Østnes

2010-01-01

196

Inhaled Steroid Drugs  

Science.gov (United States)

... One is a class of drugs called inhaled steroids. There are six medicines in this class. To ... choose among them, Consumer Reports has analyzed the steroid inhalers based on their effectiveness, safety, dosing convenience, ...

197

Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels  

Science.gov (United States)

This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have characterized it as rebounding by having steady or increasing recruitment since 1997. However, researchers have not been able to effectively determine the sex for most of the sturgeon they capture because few fish caught during surveys are releasing gametes. A total of 115 fish were sampled from May through June in 2004 and 2005 from the SCR, Michigan, USA. Of these, only four females and eight males were verified (i.e. they were releasing gametes at time of capture), resulting in very few fish with which to validate blood hormone and Vtg biomarkers of sex. Fifty-six percent of the fish were assigned a sex designation based on biomarker criteria. Correspondence between actual gonadal sex and biomarker-directed classification was good for the small subset of fish for which gonadal sex was definitively determined. Moreover, application of the steroid values in a predictive sex assignment model developed for white sturgeon misclassified only the same two fish that were misclassified with the steroid and Vtg biomarkers. The experimental results suggest a sex ratio of 1 : 2.7 (F:M), however more conclusive methods are needed to confirm this ratio because so few fish were available for sex validation. Of the 43 males, 14 were within the legal slot limit, 11 were smaller than 1067 mm total length (TL), and 18 were larger than 1270 mm TL. All 15 females were larger than 1270 mm TL, and thus protected by the slot limit criteria. Considering that lake sturgeon are threatened in Michigan, an advantage to using blood plasma assays was that fish were not harmed, and sample collection was quick, simple, and inexpensive. However, because a sufficiently large number of fish could not be validated for gonadal sex due to handling restrictions given the fish's protected status, assignment of sex is not based on a robust multi-variate model. An immediate alternative may be to use other non-invasive field methods (e.g. ultrasound, fiber-optic endoscope) to provide a more timely classification while establishing well-validated plasma hormone and Vtg-based predictive models for sex assignment of lake sturgeon. ?? 2009 Blackwell Verlag, Berlin.

Craig, J.M.; Papoulias, D.M.; Thomas, M.V.; Annis, M.L.; Boase, J.

2009-01-01

198

Adrenal Steroids Uniquely Influence Sexual Motivation Behavior in Male Rats  

Directory of Open Access Journals (Sweden)

Full Text Available The androgenic adrenal steroids dehydroepiandrosterone (DHEA and 4?-androstenedione (4-A have significant biological activity, but it is unclear if the behavioral effects are unique or only reflections of the effects of testosterone (TS. Gonadally intact male Long-Evans rats were assigned to groups to receive supplements of DHEA, 4-A, TS, corticosteroid (CORT, all at 400 µg steroid/kg of body weight, or vehicle only for 5 weeks. All males were tested in a paradigm for sexual motivation that measures time and urinary marks near an inaccessible receptive female. It was found that DHEA and 4-A supplements failed to influence time near the estrous female in the same way TS supplements did, and, indeed, 5 weeks of 4-A administration reduced the time similar to the suppressive effects of CORT after 3 weeks. Further, animals treated with DHEA or 4-A left fewer urinary marks near an estrous female than TS and control groups. These results suggest that DHEA and 4-A are not merely precursors of sex hormones, and provide support for these steroids influencing the brain and behavior in a unique fashion that is dissimilar from the effects of TS on male sexual behavior.

George T. Taylor

2012-08-01

199

Age- and sex-related changes in bone mass measured by neutron activation  

Energy Technology Data Exchange (ETDEWEB)

Total-body calcium (TBCa) measurements have been employed in two basic types of studies. In the first type, serial measurements made on an individual patient are used to trace the time variation in body calcium. In the second type of study, the absolute total body calcium of an individual is determined and compared to a standard or predicted value in order to determine the deficit or excess of calcium. Generally, the standards are derived from data obtained from normal populations and grouped by the parameters of age and sex (mean value denoted TBCa/sub m/). In the study reported in this paper, the clinical usefulness of predicted calcium (TBCa/sub p/) is evaluated. The predicted value (TBCa/sub p/) for an individual is obtained with an algorithm utilizing values of sex and age, height and lean body mass (as derived from /sup 40/K measurement). The latter two components characterize skeletal size and body habitus, respectively. For the study, 133 white women and 71 white men ranging in age from 20 to 80 years were selected from a larger population. Individuals with evidence of metabolic calcium disorders or osteoporosis were excluded. Additionally, the women and men selected were first judged to have total body potassium levels in the normal range. For each age decade, the variance of TBCa values of these individuals, when expressed in terms of TBCa/sub p/, was significantly less than when expressed in terms of TBCa/sub m/. Thus, erroneous conclusions based on Ca deficit in osteoporosis could be drawn for individuals whose height and body size differ markedly from the average, as the variation of their TBCa values often exceeds the variation in the age and sex cohort. Data on a group of osteoporotic women were compared with the normal skeletal baseline values both in terms of the TBCa and the TBCa/sub p/ values.

Cohn, S.H.; Aloia, J.F.; Vaswani, A.N.; Zanzi, I.; Vartsky, D.; Ellis, K.J.

1981-01-01

200

Age- and sex-related changes in bone mass measured by neutron activation  

International Nuclear Information System (INIS)

Total-body calcium (TBCa) measurements have been employed in two basic types of studies. In the first type, serial measurements made on an individual patient are used to trace the time variation in body calcium. In the second type of study, the absolute total body calcium of an individual is determined and compared to a standard or predicted value in order to determine the deficit or excess of calcium. Generally, the standards are derived from data obtained from normal populations and grouped by the parameters of age and sex (mean value denoted TBCa/sub m/). In the study reported in this paper, the clinical usefulness of predicted calcium (TBCa/sub p/) is evaluated. The predicted value (TBCa/sub p/) for an individual is obtained with an algorithm utilizing values of sex and age, height and lean body mass (as derived from 40K measurement). The latter two components characterize skeletal size and body habitus, respectively. For the study, 133 white women and 71 white men ranging in age from 20 to 80 years were selected from a larger population. Individuals with evidence of metabolic calcium disorders or osteoporosis were excluded. Additionally, the women and men selected were first judged to have total body potassium levels in the normal range. For each age decade, the variance of TBCa values of these individuals, when expressed in terms of TBCa/sub p/, was significantly less than when expressed in terms of TBCa/sub m/. Thus, erroneous conclusions based on Ca deficit in osteoporosis could be drawn for individuals whose height and body size differ markedly from the average, as the variation of their TBCa values often exceeds the variation in the age and sex cohort. Data on a group of osteoporotic women were compared with the normal skeletal baseline values both in terms of the TBCa and the TBCa/sub p/ values

 
 
 
 
201

When Public Protection becomes Punishment? – The UK Use of Civil Measures to Contain Sex Offender  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The last ten years has witnessed an increased use of the civil law in the UK to contain and incapacitate the sex offender. These measures have been introduced to improve community safety and public protection, as the criminal law seeks to punish and condemn. This paper explores the contention that the civil and criminal law are in danger of becoming confused and the line between the two becoming blurred. At worst the civil law is in danger of becoming a form of criminal punishment in its own ...

Terry Thomas

2006-01-01

202

Recent advances in steroid radioimmunoassay  

International Nuclear Information System (INIS)

The advances since 1974 in the techniques of measuring steroid molecules by radioimmunoassay are reviewed in this paper. They are considered under the following headings: preparation and use of antisera; preparation and use of tracers; preparation of biological samples before assay; dispensing of the reagents in the assay; separation of free and bound radioactivity; counting and data processing; quality control and standardization. (orig.)

203

MR measurement of normal pituitary gland height on midsagittal section: Age and sex differentiation  

International Nuclear Information System (INIS)

Measurement of the normal pituitary gland height was performed on magnetic resonance (MR) images of 144 subjects with no known or suspected pituitary or hypothalamic diseases. Midsagittal T1 weighted images(T1WI) were used for measurement, and mean vertical height according to age and sex group was obtained. In all age groups, the pituitary height was greater in females than in male. The group of 0-9 years in both genders showed the minimum mean pituitary height. The maximum mean height was observed in the 10-19 years age group in both genders. The height gradually decreases with increasing age after age 20 years. There was no subject with a height more than 9.0 mm in females or 8.0 mm in males. In conclusion the measurement of the normal pituitary gland height using mid-sagittal MR imaging can be used for the evaluation of the pituitary gland lesions

204

Development and Refinement of a Measure of Attitudes toward Sex Offender Treatment  

Science.gov (United States)

In recent years public attitudes toward sex offenders have become increasingly punitive. Consequently, new legislation pertaining to the sentencing and treatment of convicted sex offenders has been focused on containment and monitoring rather than rehabilitation. However, research suggests that treatment programs for sex offenders are effective in…

Wnuk, Dorota; Chapman, Jason E; Jeglic, Elizabeth L.

2006-01-01

205

Steroids in childhood epilepsy  

Directory of Open Access Journals (Sweden)

Full Text Available Treatment of epileptic encephalopathies can be very challenging as most anticonvulsant drugs fail to achieve good seizure control. Steroids are disease modifying as well as anticonvulsant in these conditions. Though steroids are accepted as the first-line treatment for infantile spasms, there are many unanswered questions with regard to the preparation, dose and duration of treatment. In this review a re-exploration of the literature is attempted. Putative mechanism of action of steroids in infantile spasms is also discussed. As steroids are being increasingly used in other epileptic encephalopathies and Rasmussen?s encephalitis, a brief discussion on the role of steroids in these conditions is attempted. The review ends with the discussion on newer neuroactive steroids in the management of epilepsy.

Ramachandrannair Rajesh

2006-01-01

206

Steroid responsive cardiomyopathy.  

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Heart disease responsive to steroids is well described in many disorders, including sarcoidosis, systemic lupus erythematosus, polyarteritis nodosa, myocarditis and Churg-Strauss syndrome. The underlying disorder is often obvious and the response is usually slow. We describe a woman who had severe left ventricular failure, cardiac dilatation and pericardial effusion which were rapidly rectified by steroid therapy. Steroid withdrawal led to recurrence of signs, which were reversed by recommenc...

Probert, Cs; Pavord, I.; Roland, J.

1990-01-01

207

Steroid hormones and bone  

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Steroid hormones have an important impact on bone. The mechanism of steroid action on bone cells is through an interaction with specific receptor proteins in the target cells. Steroid receptors are a class of molecules that function as both signal transducers and transcription factors. The receptors each have similar functional domains that are responsible for discrete functions. The mechanism of receptor action is mediated by both genomic and nongenomic pathwa...

Huang, W. H.; Zheng, M. H.

1999-01-01

208

The alteration of the urinary steroid profile under the stress  

Directory of Open Access Journals (Sweden)

Full Text Available In the second part of twentieth century anabolic-androgenic steroids were introduced into doping practice and received continuously increasing significance. In order to prove the usage of doping substances, the determination of steroid profile in the urine came into practice. Several factors may be responsible for alterations in the normal steroid profile for example age, sex and diet. The aim of this study was to find out, whether the psychological stress may cause modifications in the steroid profile and T/Et ratio. The effect of physical activity was also considered. The steroid profile was determined in the group of 34 students being in non-stress conditions and under stress immediately before an important university exam. The intensity of stress was rated by self-reported questionnaire. The GC/MS method was applied to determine the steroid profile in the urine samples. The results of the experiment have shown that psychological stress may cause significant changes in the steroid profile, especially in females. Physical activity, independently of stress significantly modified the steroid profile. In summary, observed changes in steroid profile suggest, that major fluctuations of T/Et and A/E ratios under the influence of stressogenic factors and physical activity are unlikely.

A Gronowska

2010-03-01

209

Anabolic Steroid Abuse  

Science.gov (United States)

Launched this month by the National Institute on Drug Abuse (NIDA), this Website offers research about the abuse of anabolic steroids and provides support to educators and policymakers interested in educating the public, especially teenagers, about the problem. The site provides substantial medical information in layman's terms about the composition, use, and potentially harmful effects of steroids. The site also gives statistics from the Institute's Monitoring the Future Study that shows a "significant increase" in steroid use from 1998 to 1999 among middle school males. Links for further information and education strategies are also provided. The Website is part of NIDA's Education Initiative: Science, Steroids, and Youth.

210

When Public Protection becomes Punishment? – The UK Use of Civil Measures to Contain Sex Offender  

Directory of Open Access Journals (Sweden)

Full Text Available The last ten years has witnessed an increased use of the civil law in the UK to contain and incapacitate the sex offender. These measures have been introduced to improve community safety and public protection, as the criminal law seeks to punish and condemn. This paper explores the contention that the civil and criminal law are in danger of becoming confused and the line between the two becoming blurred. At worst the civil law is in danger of becoming a form of criminal punishment in its own right and those charged with implementing it, in danger of getting their roles confused. What starts out as a civil regulatory or administrative arrangement for public safety becomes increasingly obstructive, has ‘gate-ways’ to criminal proceedings and is implemented in a punitive fashion.

Terry Thomas

2006-05-01

211

Days on feed and sex effects on live weight and carcass traits measured by ultrasound  

Directory of Open Access Journals (Sweden)

Full Text Available There is a paucity of information in the literature on body composition changes in Nellore cattle and its crosses, mainly on heifers and intact males. Ultrasound is a useful, low cost tool to easily obtain this information, with minimal animal stress. Effects of sex and days on feed on live weight (LW and ultrasound Longissimus muscle area (ULMA and subcutaneous fat thickness (UFAT measurements were evaluated in F1 Piedmont Nelore, 27 heifers (HF and 27 intact males (IM. HF and IM had an initial LW of 256 ? 5.6 and 265 ? 5.6 kg, respectively, and were fed a diet containing 77% TDN for 131 days. LW, ULMA, and UFAT were evaluated at 28-d intervals. Interactions between sex and days on feed were found for all traits studied. LW increased linearly with days on feed, and IM had greater LW than HF throughout the trial. Mean initial ULMA was 55.8 and 55.5 cm² for HF and IM, respectively, and increased linearly until the end of the experiment (78.7 and 82.8 cm², respectively. IM showed higher ULMA than HF only in the last measurement. Initial UFAT averaged 0.04 and 0.4 mm for IM and HF, respectively, and increased linearly during the feeding period (2.4 and 4.3 mm, respectively. UFAT was higher n HF than in IM during the entire experimental period. IM showed faster growth rates and protein accretion than HF in the Longissimus muscle. HF showed faster subcutaneous fat accretion.

Silva Saulo da Luz e

2005-01-01

212

Are Steroids Worth the Risk?  

Science.gov (United States)

... of the heart. Back Continue Steroids: Stacking and Addiction Some people "cycle" their steroid doses. This means ... of appetite, fatigue, restlessness, insomnia, mood swings, and depression. Strong Anabolic steroid use is illegal and banned ...

213

Mind Over Matter: Anabolic Steroids  

Science.gov (United States)

... Mind Over Matter Teaching Guide and Series Anabolic Steroids Home / Educators / NIDA Teaching Guides / Mind Over Matter Teaching Guide and Series / Anabolic Steroids Print Anabolic steroids are artificial versions of a ...

214

Age-related Purkinje cell death is steroid dependent: ROR? haplo-insufficiency impairs plasma and cerebellar steroids and Purkinje cell survival  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A major problem of ageing is progressive impairment of neuronal function and ultimately cell death. Since sex steroids are neuroprotective, their decrease with age may underlie age-related neuronal degeneration. To test this, we examined Purkinje cell numbers, plasma sex steroids and cerebellar neurosteroid concentrations during normal ageing (wild-type mice, WT), in our model of precocious ageing (Rora+/sg, heterozygous staggerer mice in which expression of the neuroprotective factor ROR? i...

Janmaat, Sonja; Akwa, Yvette; Doulazmi, Mohamed; Bakouche, Joe?lle; Gautheron, Vanessa; Liere, Philippe; Eychenne, Bernard; Pianos, Antoine; Luiten, Paul; Groothuis, Ton; Baulieu, Etienne-emile; Mariani, Jean; Sherrard, Rachel M.; Fre?de?ric, Florence

2011-01-01

215

Steroid immunoassay in clinical chemistry  

International Nuclear Information System (INIS)

This thesis reports experimental work in developing radioimmunoassays suitable for application in the routine clinical laboratory. Emphasis is placed on the cost-effectiveness of the assays. Because such an approach involves simplification of the assays, considerable emphasis is placed on the demonstration of accuracy. Experimental studies of factors which affect the specificities of steroid immunoassays are described. Factors other than measured cross-reactivities were found to influence the specificity of the immunoassay itself. These factors include other steroid binding proteins, including second antisera of a different specificity and an apparent heterogeneity of specificity within most antisera. A critical review of methods for measuring and reporting immunoassay- and antiserum specificities is included. The importance of antibody affinity in avoiding non-specific interference from, for instance proteins and minor variations in technique, is emphasised. Technical limitations, future clinical requirements, future possibilities and alternative methods of analysis are discussed. (Auth.)

216

Problems of Birds Sex Determination  

Directory of Open Access Journals (Sweden)

Full Text Available Sex determination system in birds is characterized by a homo-(Neognatae and heteromorphic (Paleognatae sex chromosomes. Heterogametic sex is female (ZZ/ZW system. DMRT1 gene is a gene regarded as a main male sex determining factor in this group of animals. The question remains about the participation of other factors (HEMOGEN, AMH etc. in appearance of testis, and the role of steroid hormones in formation of ovaries. Complete sex inversion is not typical for species with genotypic sex determination (GSD, although the effect of estrogen metabolites is noted for birds. For birds epigenetic mechanisms of regulation (methylation of DNA and non-coding RNA have been described for sex controlling genes such as CYP19A1 and DMRT1.

Antonina V. Trukhina

2014-09-01

217

About Steroids (Inhaled and Oral Corticosteroids)  

Science.gov (United States)

... Diseases > Long-Term Control Medications > About Steroids About Steroids (Inhaled and Oral Corticosteroids) What are corticosteroids (‘steroids’) ... considerations when your dosage changes? What are corticosteroids (‘steroids’)? Corticosteroids (steroids) are medicines that are used to ...

218

Clustered Occupational Interest Measurement Based on Sex-Balanced Inventory Items.  

Science.gov (United States)

The present study was undertaken to determine whether a 14-cluster occupational structure similar to Knapp's (1976) would result from factor analysis based on sex-balanced interest items. Results supported the structure found previously based on non-sex-balanced items. (Author/GK)

Knapp, Lila; Knapp, Robert R.

1982-01-01

219

Measuring Effectiveness in School Sex Education--Methodological Dilemmas in Researching an Intervention Involving Young Mothers  

Science.gov (United States)

Defining and therefore evaluating the effectiveness of school sex education is problematic because of its location at the site of struggle between competing discourses. Those discourses--summarised here as "moralistic," "harm reductionist" and "empowering"--each emphasise a different conceptualisation of sex education's intended outcomes. The…

Kidger, Judi

2006-01-01

220

Virtual characters designed for forensic assessment and rehabilitation of sex offenders: standardized and made-to-measure  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents two studies pertaining to the use of virtual characters applied in clinical forensic rehabilitation of sex offenders. The first study is about the validation of the perceived age of virtual characters designed to simulate primary and secondary sexual character of typical adult and child individuals. The second study puts to use these virtual characters in comparing a group of sex offenders and a group of non deviant individuals on their sexual arousal responses as recorded in virtual immersion. Finally, two clinical vignettes illustrating the use of made-to-measure virtual characters to more closely fit sexual preferences are presented in Discussion.

Benoît Dassylva

2010-11-01

 
 
 
 
221

The sex difference of plasma homovanillic acid is unaffected by cross-sex hormone administration in transsexual subjects  

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There is a close relationship between the brain and the endocrine system. The brain expresses receptors for sex steroids and is capable of metabolizing these hormones. We explored (1) sex differences in homovanillic acid (HVA), a metabolite of the neurotransmitter dopamine, and (2) the effects of cross-sex steroid administration in transsexual subjects. First, we compared plasma HVA levels between 38 male and 34 female healthy volunteers (not using hormone replacement therapy) of a mean age o...

Giltay, E. J.; Kho, King H.; Blansjaar, B. A.; Verbeek, M. M.; Geurtz, P. B. H.; Geleijnse, J. M.

2005-01-01

222

Sex Role Patterns in an Irish Student Sample as Measured by the Bem Sex Role Inventory (Comparisons with an American Sample).  

Science.gov (United States)

Presents findings about sex roles in 171 male and 180 female university students in Ireland who were examined by the Bem Sex Role Inventory, and discusses the validity of this test. The distribution of subjects on sex-role types showed a larger percentage of androgynous males and undifferentiated females in the Irish sample than in American…

Ryan, Gerry; And Others

1987-01-01

223

Standardization of androstenedione and estrone radioimmunoassay and profile of sex steroids, gonadotropins and prolactin - in patients with chronic anovulation due to inappropriate feedback (polycystic ovarian syndrome); Padronizacao do radioimunoensaio da androstenediona e da estrona e o perfil dos esteroides sexuais, gonadotrofinas e prolactina em pacientes com anovulacao cronica por retrocontrole improprio (sindrome dos ovarios policisticos)  

Energy Technology Data Exchange (ETDEWEB)

Full text. In order to evaluate the profile of the sex steroids gonadotropin and prolactin in polycystic ovarian syndrome (POS), 24 patients with POS were studied and compared with 20 normal women during the early follicular phase of the menstrual cycle. Radioimmunoassay techniques for androstenedione (A) and estrone (E{sub 1}) were standardized for the purpose of the study. Androstenedione and estrone were extracted from plasma with ethyl ether. The assays were maintained in equilibrium and the labelled hormone-antibody complex was then separated from the free hormone using dextran charcoal. The sensitivity of the method was 6.8 pg/tube for A and 3.7 pg/tube for E{sub 1}. Nonspecific binding ws 3.4 for A and 3.3 for E{sub 1}. The interessay error at the D50 level was 15.6 for A and 8.6 for E{sub 1}. Patients with POS had significantly higher basal levels of LH, A, T E{sub 1} and PRL and similar FSH and DHEA-S levels when compared with normal women. The LH/FSH ratio was significantly elevated and the A/T ratio was significantly decreased. The A/E{sub 1} and T/E{sub 2} ratios were elevated and the E{sub 1}/E{sub 2} was decreased, although the differences were not statistically significant. A positive correlation between A and E{sub 1} was observed in patients with POS. In view of the above data, it was concluded that: the quality control parameters of the radioimmunoassay for A and E{sub 1} standardized in the present study are considered satisfactory, and the assay could be used for diagnosis and research; the patients with POS have a different sex steroid and gonadotropin profile when compared normal women during the early follicular phase of the menstrual cycle

Vilanova, Maria do Socorro Veras

1992-12-01

224

Obesity-induced downregulation of the mitochondrial translocator protein (TSPO) impairs placental steroid production.  

Science.gov (United States)

Context: Low concentrations of estradiol and progesterone are hallmarks of adverse pregnancy outcomes as is maternal obesity. During pregnancy, placental cholesterol is the sole source of sex steroids. Cholesterol trafficking is the limiting step in sex steroid biosynthesis and is mainly mediated by the translocator protein (TSPO), present in the mitochondrial outer membrane. Objective: To investigate the effects of maternal obesity in placental sex steroid biosynthesis and TSPO regulation. Design/Participants: 144 obese (BMI 30-35) and 90 lean (BMI 19-25) women recruited at scheduled term Cesarean delivery. Placenta and maternal blood were collected. Setting: This study was conducted at MetroHealth Medical Center, Cleveland, OH. Main outcome measures: Maternal metabolic components (fasting glucose, insulin, leptin, estradiol, progesterone and total cholesterol) and placental weight were measured. Placenta (mitochondria and membranes separately) and cord blood cholesterol values were verified. Expression and regulation of TSPO and mitochondrial function were analyzed. Results: Plasma estradiol and progesterone concentrations were significantly lower (p<0.04) in obese (OP) as compared to lean (LP) women. Maternal and cord plasma cholesterol were not different between groups. Placental citrate synthase activity and mtDNA, markers of mitochondrial density, were unchanged but mitochondrial cholesterol concentrations were 40% lower in placenta of OP. TSPO gene and protein expression were decreased 2-fold in placenta of OP. In vitro trophoblast activation of innate immune pathways with LPS and long chain saturated fatty acids reduced TSPO expression by 2-3 fold (p<0.05). Conclusion: These data indicate that obesity in pregnancy impairs mitochondrial steroidogenic function through negative regulation of mitochondrial TSPO. PMID:25322273

Lassance, Luciana; Haghiac, Maricela; Minium, Judi; Catalano, Patrick; Mouzon, Sylvie Hauguel-de

2014-10-16

225

Motor function measure scale, steroid therapy and patients with Duchenne muscular dystrophy / Medida de função motora, corticoterapia e pacientes com distrofia muscular de Duchenne  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: Avaliar a evolução da função motora de pacientes com distrofia muscular de Duchenne (DMD) em corticoterapia (predinisolona e deflazacort), por meio da escala Medida da Função Motora (MFM), que avalia três dimensões de funções motoras (D1, D2, D3). MÉTODOS: Trinta e três pacientes com DMD ( [...] 22 deambulantes, seis cadeirantes e cinco que perderam a capacidade de andar ao longo do estudo) foram avaliados pela escala MFM em seis momentos durante 18 meses. RESULTADOS: Todas as funções motoras mantiveram-se estáveis durante 14 meses, exceto D1 para os pacientes que perderam a marcha. Nos pacientes deambulantes, a D2 (função motora axial e proximal) apresentou melhora durante seis meses. Melhora em D3 (função motora distal) também foi observada durante o seguimento. A D1 (postura em pé e transferências) e o escore total foram importantes para predizer a perda de marcha. CONCLUSÕES: O uso da MFM nos pacientes com DMD confirma os benefícios do tratamento com corticoides na diminuição da velocidade de progressão da doença. Abstract in english OBJECTIVE: To assess the evolution of motor function in patients with Duchenne muscular dystrophy (DMD) treated with steroids (prednisolone or deflazacort) through the Motor Function Measure (MFM), which evaluates three dimensions of motor performance (D1, D2, D3). METHODS: Thirty-three patients wit [...] h DMD (22 ambulant, 6 non-ambulant and 5 who lost the capacity to walk during the period of the study) were assessed using the MFM scale six times over a period of 18 months. RESULTS: All the motor functions remained stable for 14 months in all patients, except D1 for those who lost their walking ability. In ambulant patients, D2 (axial and proximal motor capacities) motor functions improved during six months; an improvement in D3 (distal motor capacity) was noted during the total follow-up. D1 (standing posture and transfers) and total score were useful to predict the loss of the ability to walk. CONCLUSIONS: The use of the MFM in DMD patients confirms the benefits of the steroid treatment for slowing the progression of the disease.

Elaine C. da, Silva; Darlene L., Machado; Maria B. D., Resende; Renata F., Silva; Edmar, Zanoteli; Umbertina C., Reed.

2012-03-01

226

Detection of designer steroids  

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Illicit use of performance-enhancing steroids has proliferated among a wide range of professional and amateur athletes. This problem has attracted broad public attention and has led the United States Congress to draft legislation that proposes frequent testing of athletes. However, current testing protocols are inadequate as athletes can evade detection by using novel steroids that are unknown to authorities. We have developed a strategy that overcomes this limitation by virtue of its abil...

Yuan, Xiaohui; Forman, Barry Marc

2005-01-01

227

Steroids in aquatic invertebrates.  

Science.gov (United States)

Steroid molecules are present in all invertebrates, and some of them have established hormonal roles: this is the case for ecdysteroids in arthropods and, to a lesser extent, for vertebrate-type steroids in molluscs. Steroids are not only hormones, they may also fulfill many other functions in chemical communication, chemical defense or even digestive physiology. The increasing occurrence of endocrine disruption problems caused by environmental pollutants, which interfere in particular with reproductive physiology of vertebrates but also of invertebrates has made necessary to better understand the endocrine physiology of the latter and the role of steroids in these processes. So many attempts are being made to better understand the endocrine roles of steroids in arthropods and molluscs, and to establish whether they also fulfill similar functions in other invertebrate phyla. At the moment, both the precise identification of these steroids, the determination of their origin (endogenous versus exogenous) and of their mechanism of action are under active investigation. This research takes profit of the development of genome sequencing programs on many invertebrate species, which allow the identification of receptors and/or biosynthetic enzymes, when related to their vertebrate counterparts, but the story is not so simple, as will be exemplified by estrogen receptors of molluscs. PMID:17238002

Lafont, René; Mathieu, Michel

2007-02-01

228

Maternal Condition but Not Corticosterone Is Linked to Offspring Sex Ratio in a Passerine Bird  

Science.gov (United States)

There is evidence of offspring sex ratio adjustment in a range of species, but the potential mechanisms remain largely unknown. Elevated maternal corticosterone (CORT) is associated with factors that can favour brood sex ratio adjustment, such as reduced maternal condition, food availability and partner attractiveness. Therefore, the steroid hormone has been suggested to play a key role in sex ratio manipulation. However, despite correlative and causal evidence CORT is linked to sex ratio manipulation in some avian species, the timing of adjustment varies between studies. Consequently, whether CORT is consistently involved in sex-ratio adjustment, and how the hormone acts as a mechanism for this adjustment remains unclear. Here we measured maternal baseline CORT and body condition in free-living blue tits (Cyanistes caeruleus) over three years and related these factors to brood sex ratio and nestling quality. In addition, a non-invasive technique was employed to experimentally elevate maternal CORT during egg laying, and its effects upon sex ratio and nestling quality were measured. We found that maternal CORT was not correlated with brood sex ratio, but mothers with elevated CORT fledged lighter offspring. Also, experimental elevation of maternal CORT did not influence brood sex ratio or nestling quality. In one year, mothers in superior body condition produced male biased broods, and maternal condition was positively correlated with both nestling mass and growth rate in all years. Unlike previous studies maternal condition was not correlated with maternal CORT. This study provides evidence that maternal condition is linked to brood sex ratio manipulation in blue tits. However, maternal baseline CORT may not be the mechanistic link between the maternal condition and sex ratio adjustment. Overall, this study serves to highlight the complexity of sex ratio adjustment in birds and the difficulties associated with identifying sex biasing mechanisms. PMID:25347532

Henderson, Lindsay J.; Evans, Neil P.; Heidinger, Britt J.; Adams, Aileen; Arnold, Kathryn E.

2014-01-01

229

Self-reported Sex Partner Dates for Use in Measuring Concurrent Sexual Partnerships: Correspondence Between Two Assessment Methods.  

Science.gov (United States)

Although prevalence of concurrent sexual partnerships is increasingly investigated as a driver of HIV epidemics, its measurement varies and its role in transmission dynamics remains contested. Relying on different methods of obtaining self-reported partnership histories may lead to significant differences in prevalence. This study examined the reliability of two methods for assessing dates of sex and the implications for measuring concurrent sexual partnerships. We conducted a cross-sectional reliability study using self-reported survey data from 650 women ages 18-65 years, recruited online nationwide for human papillomavirus natural history studies from 2007 to 2012. Intermethod reliability of first and last sex with the most recent partner was assessed using weighted kappa. Intraclass correlation coefficient was estimated for intramethod reliability across two consecutive questionnaires administered 4 months apart. Point prevalence of concurrent sexual partnerships at 6 months prior to the questionnaire date was similar between the two question formats (10.5 % for categorical and 10.9 % for continuous). The range between the minimum and maximum cumulative prevalence for 12 months was larger when using the categorical questions (17.0-29.6 % compared to 27.6-28.6 % using the continuous questions). Agreement between the two question formats was moderate for the date of first sex with the most recent partner (? = 0.56, 95 % CI 0.48-0.64) and almost perfect for the date of last sex (? = 0.93, 95 % CI 0.91-0.94). Longitudinal agreement for date of first sex was high for the continuous date question (ICC = 0.89, 95 % CI 0.86-0.92). Results of this reliability study can be used to inform the design of future studies of concurrent sexual partnerships and their association with HIV. PMID:25391584

Huang, Claire E; Cassels, Susan L; Winer, Rachel L

2014-11-13

230

Sex differences in angiotensin II- induced hypertension  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sex differences in the development of hypertension and cardiovascular disease have been described in humans and in animal models. In this paper we will review some of our studies which have as their emphasis the examination of the role of sex differences and sex steroids in modulating the central actions of angiotensin II (ANG II) via interactions with free radicals and nitric oxide, generating pathways within brain circumventricular organs and in central sympathomodulatory systems. Our studi...

Xue, B.; Johnson, A. K.; Hay, M.

2007-01-01

231

Sex dimorphism of cortical water diffusion in normal aging measured by magnetic resonance imaging  

Science.gov (United States)

Background: The purpose of this study was to examine sex dimorphism in water diffusion in the brain throughout the normal aging process by magnetic resonance imaging. Methods: Diffusion-weighted images covering the majority of the brain were acquired from 77 healthy participants. Both the mean water diffusivity and diffusion kurtosis were calculated from the cortical regions and parcellated according to the template in anatomical automatic labeling. The mean water diffusivity and diffusion kurtosis from both sexes were examined and subsequently correlated with age. Statistical significance was set at a threshold of p diffusivity and a decreased diffusion kurtosis in the frontal and temporal lobes. Second, a widespread age-related increase in mean water diffusivity was observed, which was more significant in the frontal, occipital, and temporal areas and in the cingulum in females. Third, the diffusion kurtosis decreased with aging but only in restricted areas for both sexes. For the interaction of aging and sex, the most significant change was observed with regards to mean diffusivity, mostly in the right amygdala. Conclusions: A sex-related dimorphism in water diffusion throughout the aging process was observed in the cortex using magnetic resonance imaging. PMID:24324433

Ng, Shu-Hang; Hsu, Wen-Chiun; Wai, Yau-Yau; Lee, Jiann-Der; Chan, Hsiao-Lung; Chen, Yao-Liang; Fung, Hon-Chung; Wu, Yih-Ru; Tsai, Ming-Lun; Wang, Jiun-Jie

2013-01-01

232

Age and Sex Differences in Controlled Force Exertion Measured by a Computing Bar Chart Target-Pursuit System  

Science.gov (United States)

This study aimed to examine the age and sex differences in controlled force exertion measured by the bar chart display in 207 males (age 42.1 [plus or minus] 19.8 years) and 249 females (age 41.7 [plus or minus] 19.1 years) aged 15 to 86 years. The subjects matched their submaximal grip strength to changing demand values, which appeared as a…

Nagasawa, Yoshinori; Demura, Shinichi

2009-01-01

233

Italian version of the Dutch Eating Behavior Questionnaire. Psychometric proprieties and measurement invariance across sex, BMI-status and age.  

Science.gov (United States)

The purpose of this study was to examine the basic psychometric proprieties of the Dutch Eating Behavior Questionnaire (DEBQ) and its measurement invariance across sex, BMI-status (normal weight/overweight), and age in a community sample of 990 Italian adults. The analysis of the dimensionality of the DEBQ using exploratory factor analysis revealed the existence of three major factors - emotional, restrained and external eating. Single and multi-group confirmatory factor analyses replicated the three-factor structure, and this dimensional structure proved to be invariant across sex, BMI-status, and age. Findings upheld the criterion-related validity (e.g., via its associations with Eating Attitudes Test-26). The DEBQ's subscales displayed high internal consistency and test-retest reliability over a 4-week period. Statistically significant differences were found when sex, BMI and age groups are compared in the latent means of emotional, external and restrained eating and they are discussed with reference to theory, past and recent empirical findings. Overall, results support the measurement invariance of the DEBQ and suggest that the Italian version is a psychometrically reliable, valid and useful measurement instrument for assessing adult eating behaviors. PMID:23994503

Dakanalis, Antonios; Zanetti, M Assunta; Clerici, Massimo; Madeddu, Fabio; Riva, Giuseppe; Caccialanza, Riccardo

2013-12-01

234

Sex differences in human virtual water maze performance: novel measures reveal the relative contribution of directional responding and spatial knowledge.  

Science.gov (United States)

Sex differences in humans on virtual water maze navigation are well established when overall performance is measured, e.g., by the total time taken to find the hidden platform, total path length, or quadrant dwell time during probe trials. Currently, it is unknown whether males are better spatial learners than females, or if overall performance differences reflect other aspects of the task unrelated to spatial memory. Here, males and females were tested on a virtual analogue of the Morris water maze. We devised a novel method of analysis in which each trial was divided into an initial trajectory phase and search phase. We also implemented a new measure of spatial learning during early and late training, by including trials in which subjects were only required to indicate where they thought the hidden target zone was located. Consistent with previous reports, males outperformed females on overall measures of task performance. Males also performed significantly better on all initial trajectory phase variables. Interestingly, only small (non-significant) differences were observed during the search phase and when spatial learning was tested without the constraints of a typical water maze trial. Our results suggest that spatial knowledge regarding the location of the hidden target zone is not the main factor responsible for overall sex differences in virtual water maze performance. Instead, the largest sex differences were observed during the initial trajectory phase of the trial, which is thought to depend on effective processing of distal features of the environment. PMID:20035800

Woolley, Daniel G; Vermaercke, Ben; Op de Beeck, Hans; Wagemans, Johan; Gantois, Ilse; D'Hooge, Rudi; Swinnen, Stephan P; Wenderoth, Nicole

2010-04-01

235

Attributions for sexual situations in men with and without erectile disorder: evidence from a sex-specific attributional style measure.  

Science.gov (United States)

This study investigated the attributional styles of men with and without sexual dysfunction for both positive and negative sexual and general events using a sex-specific version of the Attributional Style Questionnaire (Sex-ASQ), and ascertained the preliminary psychometric properties of the measure. The Sex-ASQ was created by embedding 8 hypothetical sexual events (4 positive, 4 negative) among the original 12 events in the Attributional Style Questionnaire (ASQ; C. Peterson, A. Semmel, C. von Baeyer, L. Y. Abramson, G. I. Metalsky, & M. E. Seligman, 1982). The Sex-ASQ was completed by 21 men with a principal DSM-IV diagnosis of Male Erectile Disorder (MED) and 32 male control participants. The psychometrics of the Sex-ASQ were satisfactory, but with the positive sexual event scales found to be less stable and internally consistent than the negative sexual event scales. Reasons for modest reliability of the positive event scales are discussed in terms of the original ASQ. As expected, men with MED did not differ significantly from men without sexual dysfunction in their causal attributions for general events, indicating that both groups exhibited an optimistic attributional style in general. Also as predicted, men with MED made more internal and stable causal attributions for negative sexual events than men without sexual dysfunction, and also rated negative sexual events as more important. For positive sexual events, the 2 groups did not differ in attributional style, with both groups making more external/unstable/specific causal attributions than for positive general events. Differences between explanatory style for sexual versus nonsexual events found in both sexually functional and dysfunctional men lend support for explanatory style models that propose both cross-situational consistency and situational specificity. PMID:15483370

Scepkowski, Lisa A; Wiegel, Markus; Bach, Amy K; Weisberg, Risa B; Brown, Timothy A; Barlow, David H

2004-12-01

236

Measuring DHEA-S in saliva: time of day differences and positive correlations between two different types of collection methods  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background The anabolic steroid, dehydroepiandosterone sulfate (DHEA-S), is secreted from the adrenal cortex. It plays a significant role in the body as a precursor to sex steroids as well as a lesser known role in the hypothalamic pituitary adrenal axis (HPA) response to stress. DHEA-S can be measured reliably in saliva, making saliva collection a valuable tool for health research because it minimizes the need for invasive sampling procedures (e.g., blood draws). Ty...

Klein Laura C; Whetzel Courtney A

2010-01-01

237

Does the mechanism of sex determination constrain the potential for sex manipulation? A test in geckos with contrasting sex-determining systems  

Science.gov (United States)

The concentration of yolk steroids was suggested to influence offspring gender in oviparous animals subject to both temperature-dependent sex determination (TSD) and genotypic sex determination (GSD). However, the proposed mechanisms of steroid effects are thought to differ between TSD and GSD: a direct effect of oestrogens on gonad feminisation in TSD species vs a differential induction of male-producing or female-producing gametes in GSD species. Geckos offer an ideal opportunity for testing these suggested mechanisms. Closely related gecko species differ in their modes of sex determination. They lay clutches of two synchronously formed eggs; both eggs share equal steroid levels. If identical hormonal composition and environment during vitellogenesis, gravidity and incubation determine the sex of the progeny, siblings should share the same gender in both TSD and GSD geckos. We found strong support for this prediction in a TSD gecko species. Among clutches that were incubated at the temperature that produced both sexes, there were no clutches with siblings of the opposite sex. On the other hand, about half of the clutches yielded siblings of the opposite sex in four GSD species. These results suggest that sex-determining systems constrain the ability of the female to produce single-sex siblings and, hence, it seems that the GSD mechanism constrains the opportunities for sex ratio manipulation in geckos via yolk steroid manipulation.

Kratochvíl, Lukáš; Kubi?ka, Lukáš; Landová, Eva

2008-03-01

238

Multidimensional Adolescent Self-Concepts: Their Relationship to Age, Sex, and Academic Measures.  

Science.gov (United States)

The Self Description Questionnaire II (SDQII) results from 901 Australian secondary school students were factor analyzed and the factors correlated to identify the relationship of self-concept factors to age, sex, and academic achievement. Findings supported the multidimensionality of self-concept and support the construct validity of the SDQII.…

Marsh, Herbert W.; And Others

1985-01-01

239

Female reproductive steroids and neuronal excitability.  

Science.gov (United States)

Oestrogen and progesterone have specific receptors in the central nervous system and are able to regulate neuronal development and plasticity, neuronal excitability, mitochondrial energy production, and neurotransmitter synthesis, release, and transport. On neuronal excitability, estradiol and progesterone seem to have an opposite effect, with estradiol being excitatory and progesterone and its derivative allopregnanolone being inhibitory. Estradiol augments N-methyl-D-aspartate-mediated glutamate receptor activity, while progesterone enhances gamma-aminobutyric acid-mediated chloride conductance. Sex steroid regulation of the balance of neuroexcitatory and neuroinhibitory activities may have a role in modulating clinical susceptibility to different neurological conditions such as migraine, catamenial epilepsy, premenstrual dysphoric disorder, and premenstrual syndrome. PMID:21533709

Finocchi, C; Ferrari, M

2011-05-01

240

Cardiac effects of anabolic steroids  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Anabolic steroid abuse in athletes has been associated with a wide range of adverse conditions, including hypogonadism, testicular atrophy, impaired spermatogenesis, gynaecomastia, and psychiatric disturbance. But what effect does steroid abuse have on the cardiovascular system?

Payne, J. R.; Kotwinski, P. J.; Montgomery, H. E.

2004-01-01

 
 
 
 
241

Effect of genotype, sex and slaughter weight on veal Longissimus muscle area measured by ultrasound and planimeter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this research was to determine effect of genotype (Holstein, Simmental and their crossbreeds), sex and slaughter weight groups (SW1=150-160kg and SW2=190-200kg) on veal Longissimus muscle area (LMA). Between the12th and the13th rib, two ultrasound LMA (ULMA) images were taken from each animal and carcass LMA (CLMA) traced on transparent foil was measured by planimeter. For both measures, Simmental calves had larger LMA than Holstein (P<0.001) and crossbreeds (P<0.05). Male and fema...

Zoran Lukovi?; Ivica Kos; Jelena Ramljak; Ante Ivankovi?; Nikolina Kelava; Miljenko Konja?i?

2010-01-01

242

Steroidal saponins from Lysimachia Paridiformis.  

Science.gov (United States)

A new steroidal saponin, paridiformoside B (1), was obtained from the EtOH extract of the whole plant of Lysimachia Paridiformis Franch, togerher with one steroidal sapogenin (7) and seven known steroidal saponins (2-6, 8-9). Their structures were elucidated using extensive spectroscopic techniques including 1D and 2D NMR spectra. PMID:17885834

Xu, Fu-Quan; Zhong, Hui-Min; Liu, Hai-Yang; Liu, Hai-Qing; Chen, Chang-Xiang

2007-01-01

243

Anabolic Steroids...What's the Hype?...  

Science.gov (United States)

This pamphlet uses a question-and-answer format to examine the use and abuse of anabolic steroids. It begins by explaining that all steroids are not anabolic steroids and that anabolic steroids are those used specifically to build muscles quickly. Medical uses of anabolic steroids are reviewed; how people get steroids, how they take them, and…

Landry, Gregory L.; Wagner, Lauris L.

244

Epidural Steroid Injections  

Science.gov (United States)

... using fluoroscopic (x-ray) guidance. Prior to the injection of steroid, contrast dye is used to confirm that the medication is ... to allow for more specific coverage of a single nerve and can provide ... to your pre-injection level of activities the following day. Some patients ...

245

Steroids. A Resource Guide.  

Science.gov (United States)

This guide provides information on steroid use as well as prevention and intervention strategies. It is intended to serve as a supplement to drug abuse education and prevention programs in elementary and secondary schools and as the basis for local curriculum development and instructional activities. The following topics are covered: (1) history…

New York State Education Dept., Albany. Bureau of School Health Education and Services.

246

Sex dimorphism of cortical water diffusion in normal aging measured by magnetic resonance imaging  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background The purpose of this study was to examine sex dimorphism in water diffusion in the brain throughout the normal aging process by magnetic resonance imaging. Methods Diffusion-weighted images covering the majority of the brain were acquired from 77 healthy participants. Both the mean water diffusivity and diffusion kurtosis were calculated from the cortical regions and parcellated according to the template in Anatomical Automatic Labeling. The mean water diffusivity and dif...

Jiun-JieWang; Wen-ChiunHsu; Jiann-DerLee

2013-01-01

247

Examining the effects of age, sex, and body mass index on normative median motor nerve excitability measurements.  

LENUS (Irish Health Repository)

OBJECTIVES: The purpose of this study was to build a large reference database of excitability measures in normal subjects and to examine the effects of age, sex, and BMI. METHODS: One hundred and five healthy subjects had median motor nerve excitability testing performed at the wrist using the automated threshold-tracking program, QTRAC. Statistical linear regression was used to explore relationships between nerve excitability and the independent variables. RESULTS: The main effect of age is a reduced superexcitability. Lesser effects are flattening of the normalized stimulus response curve and reduction in threshold change following strong hyperpolarizing currents. Females have lower thresholds than males and small but significant differences in voltage-gated potassium channel (KCNQ) mediated properties (late subexcitability, accommodation half time, and threshold undershoot following depolarizing electrotonus), as well as a small increase in superexcitability. BMI has no influence on nerve excitability data and does not explain sex-related differences in threshold. CONCLUSIONS: Age and sex have few and small effects on excitability parameters. SIGNIFICANCE: The expression of nodal KCNQ channels appears to be greater in females. Age-related increases in subexcitability may be attributable to changes in the muscle fibre and not the nerve.

McHugh, John C

2012-02-01

248

Nonprescription steroids on the Internet.  

Science.gov (United States)

This study evaluated the degree to which anabolic-androgenic steroids are proffered for sale over the Internet and how they are characterized on popular Web sites. Searches for specific steroid product labels (e.g., Dianabol) between March 2006 and June 2006 revealed that approximately half of the Web sites advocated their "safe" use, and roughly one third offered to sell them without prescriptions. The Web sites frequently presented misinformation about steroids and minimized their dangers. Less than 5% of the Web sites presented accurate health risk information about steroids or provided information to abusers seeking to discontinue their steroid use. Implications for education, prevention, treatment, and policy are discussed. PMID:22080724

Clement, Christen L; Marlowe, Douglas B; Patapis, Nicholas S; Festinger, David S; Forman, Robert F

2012-02-01

249

Anthropometric study with emphasis on hand and foot measurements in the Prader-Willi syndrome: sex, age and chromosome effects.  

Science.gov (United States)

Age, sex and chromosome effects on weight, height, sitting height, three head dimensions, and five hand and three foot measurements were analyzed from 57 patients (35 males and 22 females) with the Prader-Willi syndrome (PWS). No significant differences were observed in anthropometric data between PWS patients with the 15q chromosome deletion and those with normal chromosomes. Preschool children were found to have dolichocephaly, while hand and foot measurements, stature and sitting height were within normal range, although foot size was smaller than hand size in females when compared with PWS males. However, anthropometric measurements, excluding weight, head length and ankle breadth, were less than -2 SD in adult patients. Abnormal growth patterns apparently exist with significant negative correlations with age, particularly in PWS males, for height, sitting height, head circumference, and hand and foot measurements, but a significant positive correlation for weight was found in patients below 10 years of age. PMID:1997214

Butler, M G; Haynes, J L; Meaney, F J

1991-01-01

250

Safe sex  

Science.gov (United States)

Safe sex means taking steps before and during sex that can prevent you from getting an infection, or from ... the skin around the genital area. Before having sex: Get to know your partner and discuss your ...

251

Pelvic ultrasound measurements in normal girls: relation to puberty and sex hormone concentration.  

Science.gov (United States)

Pelvic ultrasonography was performed on 75 normal girls. Values were obtained for uterine length, fundal/cervical ratio (FCR), ovarian volume and sex hormones. The resultant data were grouped according to age and pubertal stage (Tanner). For uterine length, FCR and ovarian volume, the data were positively skewed, and the variance increased with age and pubertal stage (p uterus underwent a regular increase in size and the corpus gradually became larger than the cervix. Uterine length, right ovary volume, FCR and hormones (serum estradiol, follicle-stimulating hormone and luteinizing hormone) showed a correlation with the Tanner score (p pubertal stage and serum estradiol level. PMID:9777573

Orbak, Z; Sa?söz, N; Alp, H; Tan, H; Yildirim, H; Kaya, D

1998-01-01

252

Relation between Serum Testosterone, Serum Estradiol, Sex Hormone-Binding Globulin, and Geometrical Measures of Adult Male Proximal Femur Strength  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Context: Although previous studies have indicated associations between circulating testosterone (T) or estradiol (E2) concentrations and bone mineral density, the relationship between gonadal steroids and skeletal geometry is not well defined.

Travison, Thomas G.; Araujo, Andre B.; Beck, Thomas J.; Williams, Rachel E.; Clark, Richard V.; Leder, Benjamin Z.; Mckinlay, John B.

2009-01-01

253

Extranuclear steroid receptors are essential for steroid hormone actions.  

Science.gov (United States)

Steroid hormones are produced throughout the phylogenetic tree, from plants to mammals. In the past 40 years, steroid receptors localized to the nucleus have been recognized as being important to mediating steroid action in many organs. This action mainly arises from the regulation of key genes that are important for organ development and function. These include but are not limited to genes influencing the reproductive tract, mammary glands, bone, brain, fat differentiation, pituitary hormone regulation, and metabolic effects in many organs. Unfortunately, steroids also promote the development of hormone-responsive cancers, including breast, uterus, and prostate cancer. It has also been shown that steroid receptors exist outside the nucleus in many organs and cells, with unclear impact for normal development, health, and disease. This review describes the evidence from many laboratories that these receptors exist and function with nuclear receptors to provide the full impact of all steroid hormones. PMID:25587652

Levin, Ellis R

2015-01-14

254

Measurements of vertebral shape by radiographic morphometry: sex differences and relationships with vertebral level and lumbar lordosis  

Energy Technology Data Exchange (ETDEWEB)

Objective. To examine sex-related and vertebral-level-specific differences in vertebral shape and to investigate the relationships between the lumbar lordosis angle and vertebral morphology. Design and patients. Lateral thoracic and lumbar spine radiographs were obtained with a standardized protocol in 142 healthy men and 198 healthy women over 50 years old. Anterior (Ha), central (Hc) and posterior (Hp) heights of each vertebra from T4 to L4 were measured using a digitizing technique, and the Ha/Hp and Hc/Hp ratios were calculated. The lumbar lordosis angle was measured on the lateral lumbar spine radiographs. Results. Ha/Hp and Hc/Hp ratios were smaller in men than women by 1.8% and 0.7%, respectively, and these ratios varied with vertebral level. Significant correlations were found between vertebral shape and the lumbar lordosis angle. Conclusions. These results demonstrate that vertebral shape varies significantly with sex, vertebral level and lumbar lordosis angle. Awareness of these relationships may help prevent misdiagnosis in clinical vertebral morphometry. (orig.) With 4 figs., 2 tabs., 17 refs.

Cheng, X.G.; Sun, Y.; Boonen, S.; Nicholson, P.H.F.; Dequeker, J. [Arthritis and Metabolic Bone Disease Research Unit, U.Z. Pellenberg, Division of Rheumatology, Pellenberg (Belgium); Brys, P. [Radiology Department, University Hospitals, Katholieke Universiteit Leuven, Leuven (Belgium); Felsenberg, D. [Radiology Department, Freie Univ. Berlin (Germany)

1998-07-01

255

Accessory sex glands as a tool to measure the efficacy of immunocastration in male pigs.  

Science.gov (United States)

The use of an anti-gonadotropin-releasing hormone vaccine for immunocastration of male pigs has been recently approved in the European Union. This technique is potentially useful for avoiding both castration-associated pain for the animal and boar taint in pork. However, some animals may escape immunocastration and be slaughtered as entire males, potentially exhibiting boar taint. Therefore, it is important to check the efficacy of immunocastration on the slaughter line. To achieve that, the currently proposed method, based on testis weight, is not fully reliable because there is some overlap in the distributions of testis weight between immunocastrates and entire males. On the basis of literature data on the effect of immunocastration on the development of accessory sex glands, this paper provides evidence that the weight of seminal vesicles might be a much better criterion for checking the efficacy of immunocastration, because their size decreases more rapidly, and to a greater extent, than that of the testis. PMID:22444264

Bonneau, M

2010-06-01

256

Effect of genotype, sex and slaughter weight on veal Longissimus muscle area measured by ultrasound and planimeter  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this research was to determine effect of genotype (Holstein, Simmental and their crossbreeds, sex and slaughter weight groups (SW1=150-160kg and SW2=190-200kg on veal Longissimus muscle area (LMA. Between the12th and the13th rib, two ultrasound LMA (ULMA images were taken from each animal and carcass LMA (CLMA traced on transparent foil was measured by planimeter. For both measures, Simmental calves had larger LMA than Holstein (P<0.001 and crossbreeds (P<0.05. Male and female calves did not differ significantly in ULMA and CLMA. Calves of SW2 group had larger LMA (P<0.0001 than SW1 group. High correlation coefficient between ULMA and CLMA was determined in this research. Veal LMA was significantly affected by genotype and slaughter weight. According to high correlation coefficients, ultrasound can be useful in estimating carcass traits of cattle at early age.

Zoran Lukovi?

2010-01-01

257

Nonprescription Steroids on the Internet  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study evaluated the degree to which anabolic-androgenic steroids are proffered for sale over the Internet and how they are characterized on popular websites. Searches for specific steroid product labels (e.g., Dianabol) between March and June, 2006 revealed that approximately half of the websites advocated their “safe” use, and roughly one-third offered to sell them without prescriptions. The websites frequently presented misinformation about steroids and minimized their dangers. Les...

Mcdonald, Christen L.; Marlowe, Douglas B.; Patapis, Nicholas S.; Festinger, David S.; Forman, Robert F.

2012-01-01

258

A simple method for measuring sex-hormone binding protein (SHBP) - typical values in men and women and in pregnant women  

International Nuclear Information System (INIS)

Assuming that the binding forces between steroid hormones and their binding proteins are similar to those between antigens and their antibodies, the authors describe how to determine SHBP activity by a dilution method analogous to that used for titration of antisera in radioimmunoassay. The method consists of the following stages: (1) plasma dilution; (2) incubation of the dilution with 20,000dis/min of 1,2-3H-testosterone; (3) separation of the fraction of tracer bound to the SHBP by precipitation with ammonium sulphate; (4) centrifugation and measurement of the supernatant; and (5) plotting of the results on a graph where the axis of ordinates represents the quotient given by bound steroid over free steroid (U/L) and the abscissa represents the plasma dilutions. The values are expressed as the 50% bound titre. An advantage of the method is the higher sensitivity of the dilution curves in the steepest part where the 50% bound is encountered; it is thus not necessary to use the saturation part of the curves where sensitivity is lost owing to the steeper slope. A further advantage of the method is that there is no need for costly processes such as dialysis. The SHBP values obtained for healthy subjects were as follows: 1/5 for men, 1/93 for women, and 1/360 in pregnant women. These physiological values showed no overlapping. (author)

259

Steroid responsive meningoencephalitis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

PHOTOS 1-2: Steroid responsive meningitis-arteritis (SRMA) is an immune mediated, inflammatory disease of the meninges and associated vasculature that is commonly documented in dogs. SRMA can occur in any breed of dog although some breeds like beagles, boxers, Bernese mountain dogs, Weimeraners and Nova Scotia duck tolling retrievers are more likely to be affected. Affected dogs may be seen to stand with an arched spine and be reluctant to walk as a result of pain. Furthermore, the dog may re...

Schoor, Mirinda

2008-01-01

260

2,3,7,8-Tetrachlorodibenzo-p-dioxin activates the aryl hydrocarbon receptor and alters sex steroid hormone secretion without affecting growth of mouse antral follicles in vitro.  

Science.gov (United States)

The persistent environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an ovarian toxicant. These studies were designed to characterize the actions of TCDD on steroidogenesis and growth of intact mouse antral follicles in vitro. Specifically, these studies tested the hypothesis that TCDD exposure leads to decreased sex hormone production/secretion by antral follicles as well as decreased growth of antral follicles in vitro. Since TCDD acts through binding to the aryl hydrocarbon receptor (AHR), and the AHR has been identified as an important factor in ovarian function, we also conducted experiments to confirm the presence and activation of the AHR in our tissue culture system. To do so, we exposed mouse antral follicles for 96 h to a series of TCDD doses previously shown to have effects on ovarian tissues and cells in culture, which also encompass environmentally relevant and pharmacological exposures (0.1-100 nM), to determine a dose response for TCDD in our culture system for growth, hormone production, and expression of the Ahr and Cyp1b1. The results indicate that TCDD decreases progesterone, androstenedione, testosterone, and estradiol levels in a non-monotonic dose response manner without altering growth of antral follicles. The addition of pregnenolone substrate (10 ?M) restores hormone levels to control levels. Additionally, Cyp1b1 levels were increased by 3-4 fold regardless of the dose of TCDD exposure, evidence of AHR activation. Overall, these data indicate that TCDD may act prior to pregnenolone formation and through AHR transcriptional control of Cyp1b1, leading to decreased hormone levels without affecting growth of antral follicles. PMID:22483799

Karman, Bethany N; Basavarajappa, Mallikarjuna S; Craig, Zelieann R; Flaws, Jodi A

2012-05-15

 
 
 
 
261

Steroids and endocrine disruptors-History, recent state of art and open questions.  

Science.gov (United States)

This introductory chapter provides an overview of the levels and sites at which endocrine disruptors (EDs) affect steroid actions. In contrast to the special issue of Journal of Steroid Biochemistry and Molecular Biology published three years ago and devoted to EDs as such, this paper focuses on steroids. We tried to point to more recent findings and opened questions. EDs interfere with steroid biosynthesis and metabolism either as inhibitors of relevant enzymes, or at the level of their expression. Particular attention was paid to enzymes metabolizing steroid hormones to biologically active products in target cells, such as aromatase, 5?-reductase and 3?-, 11?- and 17?-hydroxysteroid dehydrogenases. An important target for EDs is also steroid acute regulatory protein (StAR), responsible for steroid precursor trafficking to mitochondria. EDs influence receptor-mediated steroid actions at both genomic and non-genomic levels. The remarkable differences in response to various steroid-receptor ligands led to a more detailed investigation of events following steroid/disruptor binding to the receptors and to the mapping of the signaling cascades and nuclear factors involved. A virtual screening of a large array of EDs with steroid receptors, known as in silico methods (computer simulation), is another promising approach for studying quantitative structure activity relationships and docking. New data may be expected on the effect of EDs on steroid hormone binding to selective plasma transport proteins, namely transcortin and sex hormone-binding globulin. Little information is available so far on the effects of EDs on the major hypothalamo-pituitary-adrenal/gonadal axes, of which the kisspeptin/GPR54 system is of particular importance. Kisspeptins act as stimulators for hormone-induced gonadotropin secretion and their expression is regulated by sex steroids via a feed-back mechanism. Kisspeptin is now believed to be one of the key factors triggering puberty in mammals, and various EDs affect its expression and function. Finally, advances in analytics of EDs, especially those persisting in the environment, in various body fluids (plasma, urine, seminal fluid, and follicular fluid) are mentioned. Surprisingly, relatively scarce information is available on the simultaneous determination of EDs and steroids in the same biological material. This article is part of a Special Issue entitled 'Endocrine disruptors & steroids'. PMID:24816231

Hampl, Richard; Kubátová, Jana; Stárka, Luboslav

2014-05-01

262

Physicochemical and biological properties of new steroid metal complexes  

International Nuclear Information System (INIS)

The aim of this investigation was to prepare stable steroid metal chelates by chemical conversion of the natural steroid hormones testerone, 5?-dihydrotestosterone (5?-DHT) and estradiol and to characterize these by means of their spectroscopic and other physico-chemical properties. In addition, various measuring techniques for the qualitative and quantitative study of complex stabilities and hydrolytic properties were employed. The distribution of some tritiated steroid metal complexes in the tissues of rats was tested using whole animal autoradiography, mainly with a view to identifying whether selective concentration occurs in certain organs. (orig.)

263

Steroids/Nutritional Supplements/Antibiotics  

Science.gov (United States)

Steroids/Nutritional Supplements/Antibiotics There are multiple steroid/supplemental treatments for Duchenne although there is little agreement ( ... creatine and Duchenne continue. back to top Anabolic steroids These, which act to build tissues in the ...

264

Advances in steroid analysis '84  

International Nuclear Information System (INIS)

The 69 papers published in the present volume cover the analysis of all important groups of steroids. The majority of the papers were presented by leading steroid analysts from 16 countries. Most papers describe immunological (RIA, EIA, fluoroimmunoassay), HPLC and GC-MS methods. (orig.)

265

Crystallization of steroids in gels  

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The crystal growth and characterization of certain steriods, viz., cholesterol, cholesteryl acetate, ?-sitosterol, progesterone and testosterone, in a silica gel medium is discussed. The present study shows that the single test tube diffusion method can be used to grow crystals of steroids in a silica gel medium by the reduction of steroid solubility.

Kalkura, S. Narayana; Devanarayanan, S.

1991-03-01

266

Role of steroids in COPD  

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There has been a lot of debate regarding the role of steroids in the management of Chronic Obstructive Pulmonary Disease. Now with a better understanding of the pathophysiology of COPD, the role of steroids in the management of COPD has become clearer.

Vishnu Sharma

2002-01-01

267

Role of Steroids in COPD  

Directory of Open Access Journals (Sweden)

Full Text Available There has been a lot of debate regarding the role of steroids in the management of Chronic Obstructive Pulmonary Disease. Now with a better understanding of the pathophysiology of COPD, the role of steroids in the management of COPD has become clearer.

Vishnu Sharma

2002-04-01

268

Roles of Steroids in Nematodes  

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The inability of nematodes to biosynthesize steroids de novo and the resulting dependence of parasitic nematodes upon their hosts have enhanced the importance of elucidating the metabolism of sterols and the hormonal and other functions of steroids in nematodes. Biochemical research has revealed th...

269

ANABOLIC ANDROGENIC STEROIDS AND DEPENDENCE  

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Full Text Available Anabolic androgenic steroids are used for sportive, cosmetic, therapeutic and occupational reasons and there are many side effects reported (George, 2005; Nieminen et al., 1996; O'Sullivan et al., 2000. Prevalence of anabolic steroids’ use also indicates the importance of this topic. Moreover, it is now known that use of anabolic steroids could lead to dependence which could be psychological or/and physiological (Copeland et al., 2000. It isimportant to know about all aspects of anabolic steroids including dependence. Therefore, this study has attempted to give an insight into use of anabolic steroids and dependence. The discussion will focus on prevalence, reasons, and side effects of use and physiological and psychological dependence

IHSAN SARI

2010-12-01

270

Sex Differences in Sum Scores May Be Hard to Interpret: The Importance of Measurement Invariance  

Science.gov (United States)

In most assessment instruments, distinct items are designed to measure a trait, and the sum score of these items serves as an approximation of an individual's trait score. In interpreting group differences with respect to sum scores, the instrument should measure the same underlying trait across groups (e.g., male/female, young/old). Differences…

Slof-Op 't Landt, M. C. T.; van Furth, E. F.; Rebollo-Mesa, I.; Bartels, M.; van Beijsterveldt, C. E. M.; Slagboom, P. E.; Boomsma, D. I.; Meulenbelt, I.; Dolan, C. V.

2009-01-01

271

MEDICAL ISSUES ASSOCIATED WITH ANABOLIC STEROID USE: ARE THEY EXAGGERATED?  

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For the past 50 years anabolic steroids have been at the forefront of the controversy surrounding performance enhancing drugs. For almost half of this time no attempt was made by sports governing bodies to control its use, and only recently have all of the major sports governing bodies in North America agreed to ban from competition and punish athletes who test positive for anabolic steroids. These punitive measures were developed with the primary concern for promotion of fair play and elimin...

Hoffman, Jay R.; Ratamess, Nicholas A.

2006-01-01

272

Current concepts in anabolic-androgenic steroids.  

Science.gov (United States)

Anabolic-androgenic steroids (AAS) are synthetic derivatives of testosterone. According to surveys and media reports, the legal and illegal use of these drugs is gaining popularity. Testosterone restores sex drive and boosts muscle mass, making it central to 2 of society's rising preoccupations: perfecting the male body and sustaining the male libido. The anabolic effects of AAS have been questioned for decades, but recent scientific investigation of supraphysiologic doses supports the efficacy of these regimens. Testosterone has potent anabolic effects on the musculoskeletal system, including an increase in lean body mass, a dose-related hypertrophy of muscle fibers, and an increase in muscle strength. For athletes requiring speed and strength and men desiring a cosmetic muscle makeover, illegal steroids are a powerful lure, despite the risk of subjective side effects. Recent clinical studies have discovered novel therapeutic uses for physiologic doses of AAS, without any significant adverse effects in the short term. In the wake of important scientific advances during the past decade, the positive and negative effects of AAS warrant reevaluation. Guidelines for the clinical evaluation of AAS users will be presented for sports medicine practitioners. PMID:14977687

Evans, Nick A

2004-03-01

273

Sex Chromosome  

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A sex chromosome is one of the two chromosomes that specify an organism's genetic sex. Humans have two kinds of sex chromosomes, one called X and the other Y. Normal females possess two X chromosomes and normal males one X and one Y.

Darryl Leja (National Human Genome Research Institute REV)

2005-04-14

274

Aplicação da Cromatografia Líquida de Alta Performance Como Método Preparativo Para a Dosagem de Esteróides Hormonais Por RIE: Dosagens de 17OH-Progesterona e Diidrotestosterona Preparative HPLC for Steroid Measurements: Determinations of 170H-Progesterone and Dihydrotestosterone  

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Full Text Available A dosagem dos esteróides hormonais tem apresentado evolução técnica significativa, sendo os principais esteróides de interesse clínico dosados, atualmente, por métodos simples, rápidos e automatizados. Existe, no entanto, um compromisso em detrimento da exatidão, que é mais evidente na determinação de esteróides de menor concentração relativa e maior número de interferentes potenciais, como a 17-hidroxiprogesterona (17OHP, a diidrotestosterona (DHT e outros. Nestes casos, um processo preparativo versátil e robusto é fundamental para garantir resultados com alto grau de exatidão. Apresentamos a padronização de um processo preparativo baseado em cromatografia líquida de alta performance (HPLC comparado à cromatografia em coluna de celite para a dosagem de 17OHP e DHT. Os anticorpos empregados nos respectivos radioimunoensaios apresentam especificidade semelhante aos descritos na literatura. As amostras foram inicialmente extraídas em éter etílico e em seguida submetidas ao processo cromatográfico. Amostras de soro provenientes da rotina foram dosadas em paralelo pelos dois métodos, sendo 57 amostras para 17OHP e 84 para DHT. Não houve diferença significativa entre os resultados, e os índices de correlação foram elevados (R= 0,95 e 0,97. Os resultados comprovam que a aplicação do HPLC é válida, além de ser mais reprodutível, versátil e menos operador-dependente. Sua aplicação mais ampla permitirá uma melhora de exatidão na dosagem de esteróides de baixa concentração relativa, onde os métodos mais simples resultam em valores falsamente elevados.Measurement of steroid hormones has undergone a significant technical evolution so that steroids with greater clinical interest are, nowadays, measured with methods that are simple, fast and prone to automation. Nevertheless, a compromise is made in detriment of accuracy, which is more evident with steroids with lower concentration and more potential interferents, as 17-hydroxyprogesterone (17OHP, dihydrotestosterone (DHT, and others. In such cases, a robust and versatile preparative process is of utmost importance to warrant results with the highest degree of accuracy. In this paper we present the results obtained with the use of a preparative process based on high-pressure chromatography (HPLC for the measurement of 17OHP and DHT, as compared with a process based on celite column chromatography. The antibodies used in the radioimmunoassays have similar specificity to those previously described for these kinds of assays. Samples were initially extracted in ethyl ether and then submitted to HPLC. Routine samples (57 for 17OHP and 84 for DHT were measured in parallel with both methods. The differences between results were not statistically significant, and the correlation indexes were high (R= 0.95 and 0.97. Our results confirm that systems based on HPLC are valid, besides being more robust, versatile and operator independent. A more pervasive application of HPLC preparation systems will allow an improvement in the accuracy of steroid measurements, specially those with low concentrations, where simple preparative processes result in falsely elevated results.

José Gilberto H. Vieira

2002-02-01

275

Aplicação da Cromatografia Líquida de Alta Performance Como Método Preparativo Para a Dosagem de Esteróides Hormonais Por RIE: Dosagens de 17OH-Progesterona e Diidrotestosterona / Preparative HPLC for Steroid Measurements: Determinations of 170H-Progesterone and Dihydrotestosterone  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A dosagem dos esteróides hormonais tem apresentado evolução técnica significativa, sendo os principais esteróides de interesse clínico dosados, atualmente, por métodos simples, rápidos e automatizados. Existe, no entanto, um compromisso em detrimento da exatidão, que é mais evidente na determinação [...] de esteróides de menor concentração relativa e maior número de interferentes potenciais, como a 17-hidroxiprogesterona (17OHP), a diidrotestosterona (DHT) e outros. Nestes casos, um processo preparativo versátil e robusto é fundamental para garantir resultados com alto grau de exatidão. Apresentamos a padronização de um processo preparativo baseado em cromatografia líquida de alta performance (HPLC) comparado à cromatografia em coluna de celite para a dosagem de 17OHP e DHT. Os anticorpos empregados nos respectivos radioimunoensaios apresentam especificidade semelhante aos descritos na literatura. As amostras foram inicialmente extraídas em éter etílico e em seguida submetidas ao processo cromatográfico. Amostras de soro provenientes da rotina foram dosadas em paralelo pelos dois métodos, sendo 57 amostras para 17OHP e 84 para DHT. Não houve diferença significativa entre os resultados, e os índices de correlação foram elevados (R= 0,95 e 0,97). Os resultados comprovam que a aplicação do HPLC é válida, além de ser mais reprodutível, versátil e menos operador-dependente. Sua aplicação mais ampla permitirá uma melhora de exatidão na dosagem de esteróides de baixa concentração relativa, onde os métodos mais simples resultam em valores falsamente elevados. Abstract in english Measurement of steroid hormones has undergone a significant technical evolution so that steroids with greater clinical interest are, nowadays, measured with methods that are simple, fast and prone to automation. Nevertheless, a compromise is made in detriment of accuracy, which is more evident with [...] steroids with lower concentration and more potential interferents, as 17-hydroxyprogesterone (17OHP), dihydrotestosterone (DHT), and others. In such cases, a robust and versatile preparative process is of utmost importance to warrant results with the highest degree of accuracy. In this paper we present the results obtained with the use of a preparative process based on high-pressure chromatography (HPLC) for the measurement of 17OHP and DHT, as compared with a process based on celite column chromatography. The antibodies used in the radioimmunoassays have similar specificity to those previously described for these kinds of assays. Samples were initially extracted in ethyl ether and then submitted to HPLC. Routine samples (57 for 17OHP and 84 for DHT) were measured in parallel with both methods. The differences between results were not statistically significant, and the correlation indexes were high (R= 0.95 and 0.97). Our results confirm that systems based on HPLC are valid, besides being more robust, versatile and operator independent. A more pervasive application of HPLC preparation systems will allow an improvement in the accuracy of steroid measurements, specially those with low concentrations, where simple preparative processes result in falsely elevated results.

José Gilberto H., Vieira; Odete H., Nakamura; Keiko O., Noguti.

2002-02-01

276

Assessment of Borderline Personality Features in Population Samples: Is the Personality Assessment Inventory-Borderline Features Scale Measurement Invariant across Sex and Age?  

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Borderline personality disorder (BPD) is more often diagnosed in women than in men, and symptoms tend to decline with age. Using a large community sample, the authors investigated whether sex and age differences in four main features of BPD, measured with the "Personality Assessment Inventory-Borderline Features" scale (PAI-BOR; Morey, 1991), are…

De Moor, Marleen H. M.; Distel, Marijn A.; Trull, Timothy J.; Boomsma, Dorret I.

2009-01-01

277

Seasonal modulation of immunity by melatonin and gonadal steroids in a short day breeder goat Capra hircus.  

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Role of melatonin in regulation of immunity and reproduction has never been studied in detail in goats. The aim of the present study was to explore hormonal regulation of immunity in goats with special reference to melatonin. Plasma of male and female goats (n = 18 per sex per season) was processed for hormonal (estrogen, testostrone, and melatonin) and cytokine (interleukin [IL-2], IL-6, and tumor necrosis factor ?) measurements during three seasons, i.e., summer, monsoon, and winter. To assess cell-mediated immune response, percent stimulation ratio of thymocytes was recorded during three seasons. To support and establish the modulation by hormones, Western blot analysis for expressions of melatonin receptors (MT1, MT2), androgen receptor, and estrogen receptor ? and estimations of marker enzymes, arylalkylamine N-acetyltransferase for melatonin and 3?-hydroxysteroid dehydrogenase activities for steroidogenesis were performed in thymus. All the hormones and cytokines were estimated by commercial kits. Biochemical, immunologic, and Western blot analyses were done by standardized protocols. We noted a significant increase in estrogen and testosterone levels (P < 0.05) in circulation during monsoon along with melatonin (P < 0.05) presenting a parallel relationship. Expressions of melatonin receptors (MT1 and MT2) in thymus of both the sexes were significantly high (P < 0.01) during winter. Estrogen receptor ? expression in female thymus was significantly high during monsoon (P < 0.05). However, androgen receptor showed almost static expression pattern in male thymus during three seasons. Further, both arylalkylamineN-acetyltransferase and 3?-hydroxysteroid dehydrogenase enzyme activities were significantly high (P < 0.05; P < 0.01, respectively) during monsoon. These results suggest that there may be a functional parallelism between gonadal steroids and melatonin as melatonin is progonadotrophic in goats. Cell-mediated immune parameters (percent stimulation ratio of thymocytes) and circulatory levels of cytokines (IL-2, IL-6, and tumor necrosis factor ?) were significantly high (P < 0.01) during monsoon. In vitro supplementation of gonadal steroids to T-cell culture suppressed immunity but cosupplementation with melatonin restored it. Further, we may also suggest that reproductive and immune seasonality are maintained by variations in circulatory hormones and local synthesis of melatonin and gonadal steroids. These functional interactions between melatonin and gonadal steroid might be of great importance in regulating the goat immunity by developing some hormonal microcircuit (gonadal steroid and melatonin) in lymphatic organs. PMID:25175759

Ghosh, Somenath; Singh, Amaresh K; Haldar, Chandana

2014-11-01

278

Reactive Arrays of Colorimetric Sensors for Metabolite and Steroid Identification  

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Full Text Available The work described herein examines a rapid mix-and-measure method called DETECHIP suitable for screening of steroids and metabolites. The addition of steroids and metabolites to reactive arrays of colorimetric sensors generated characteristic color “fingerprints” that were used to identify the analyte. A color analysis tool was used to identify the analyte pool that now includes biologically relevant analytes. The mix-and-measure arrays allowed the detection of disease metabolites, orotic acid and argininosuccinic acid; and the steroids androsterone, 1,4-androstadiene, testosterone, stanozolol, and estrone. The steroid 1,4-androstadiene was also detected by this method while dissolved in synthetic urine. Some of the steroids, such as androstadiene, stanozolol, and androsterone were co-dissolved with (2-hydroxypropyl-?-cyclodextrin in order to increase solubility in aqueous buffered solutions. The colorimetric arrays do not intend to eliminate ELISA or mass spectroscopy based screening, but to possibly provide an alternative analytical detection method for steroids and metabolites.

Gary Batres

2014-03-01

279

Steroids in Athletics: One University's Experience.  

Science.gov (United States)

Presents an account of one university's experience in conducting an investigation into possible steroid use by student athletes and the development of a program to deal with the problem. Discusses why athletes use steroids and how steroids are taken. Concludes it is likely many steroid-related deaths of athletes go undetected. (Author/ABL)

Lopez, Mike

1990-01-01

280

Aggressive Behaviors in Adult SF-1 Knockout Mice That Are Not Exposed to Gonadal Steroids During Development  

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Sex hormones are a major factor responsible for the development of sex differences. Steroidogenic factor 1 (SF-1) is a key regulator of gonadal and adrenal development, and SF-1 knockout mice (SF-1 KO) are born without gonads and adrenal glands. Consequently, these mice are not exposed to gonadal sex steroids. SF-1 KO pups die shortly after birth due to adrenal deficiency. In the present study, SF-1 KO mice were rescued by neonatal corticosteroid injections followed by adrenal transplantation...

Grgurevic, Neza; Bu?defeld, Tomaz; Tobet, Stuart A.; Rissman, Emilie F.; Majdic, Gregor

2008-01-01

 
 
 
 
281

A quantitiative LC-MS/MS method for the measurement of arachidonic acid, prostanoids, endocannabinoids, N-acylethanolamines and steroids in human plasma.  

Science.gov (United States)

Free arachidonic acid is functionally interlinked with different lipid signaling networks including those involving prostanoid pathways, the endocannabinoid system, N-acylethanolamines, as well as steroids. A sensitive and specific LC-MS/MS method for the quantification of arachidonic acid, prostaglandin E2, thromboxane B2, anandamide, 2-arachidonoylglycerol, noladin ether, lineoyl ethanolamide, oleoyl ethanolamide, palmitoyl ethanolamide, steroyl ethanolamide, aldosterone, cortisol, dehydroepiandrosterone, progesterone, and testosterone in human plasma was developed and validated. Analytes were extracted using acetonitrile precipitation followed by solid phase extraction. Separations were performed by UFLC using a C18 column and analyzed on a triple quadrupole MS with electron spray ionization. Analytes were run first in negative mode and, subsequently, in positive mode in two independent LC-MS/MS runs. For each analyte, two MRM transitions were collected in order to confirm identity. All analytes showed good linearity over the investigated concentration range (r>0.98). Validated LLOQs ranged from 0.1 to 190ng/mL and LODs ranged from 0.04 to 12.3ng/mL. Our data show that this LC-MS/MS method is suitable for the quantification of a diverse set of bioactive lipids in plasma from human donors (n=32). The determined plasma levels are in agreement with the literature, thus providing a versatile method to explore pathophysiological processes in which changes of these lipids are implicated. PMID:25436483

Gachet, María Salomé; Rhyn, Peter; Bosch, Oliver G; Quednow, Boris B; Gertsch, Jürg

2015-01-22

282

Impaired hepatic drug and steroid metabolism in congenital adrenal hyperplasia due to P450 oxidoreductase deficiency  

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Objective: Patients with congenital adrenal hyperplasia due to P450 oxidoreductase (POR) deficiency(ORD) present with disordered sex development and glucocorticoid deficiency. This is due to disruption of electron transfer from mutant POR to microsomal cytochrome P450 (CYP) enzymes that play a key role in glucocorticoid and sex steroid synthesis. POR also transfers electrons to all major drugmetabolizing CYP enzymes, including CYP3A4 that inactivates glucocorticoid and oestrogens. However, wh...

Tomalik-scharte, D.; Maiter, D.; Kirchheiner, J.; Ivison, H. E.; Fuhr, U.; Arlt, Wiebke

2010-01-01

283

Industrial and Compendial Steroid Analysis  

Science.gov (United States)

The aim of this section is to give an overview of the requirements of steroid analysis in pharmaceutical industry and to cover the methodological aspects of these requirements with regard to quality control of bulk steroid drugs and drug formulations. Although this is an important area, the challenges here are not comparable with those in biological-clinical steroid analysis, which was the sole topic of the first edition of this book. This is reflected by the much smaller number of research publications dealing with this pharmaceutical area of steroid analyses. Only a few (more or less obsolete) books are available (Görög and Szász, 1978; Görög, 1983, 1989). The newer developments in this area are summarised in a comprehensive review (Görög, 2004), on which this chapter is based.

Görög, Sándor

284

Dehydroepiandrosterone: A neuroactive steroid.  

Science.gov (United States)

Dehydroepiandrosterone (DHEA) and its sulfate bound form (DHEAS) are important steroids of mainly adrenal origin. They are produced also in gonads and in the brain. Dehydroepiandrosterone easily crosses the brain-blood barrier and in part is also produced locally in the brain tissue. In the brain, DHEA exerts its effects after conversion to either testosterone and dihydrotestosterone or estradiol via androgen and estrogen receptors present in the most parts of the human brain, through mainly non-genomic mechanisms, or eventually indirectly via the effects of its metabolites formed locally in the brain. As a neuroactive hormone, DHEA in co-operation with other hormones and transmitters significantly affects some aspects of human mood, and modifies some features of human emotions and behavior. It has been reported that its administration can increase feelings of well-being and is useful in ameliorating atypical depressive disorders. It has neuroprotective and antiglucocorticoid activity and modifies immune reactions, and some authors have also reported its role in degenerative brain diseases. Here we present a short overview of the possible actions of dehydroepiandrosterone and its sulfate in the brain, calling attention to various mechanisms of their action as neurosteroids and to prospects for the knowledge of their role in brain disorders. PMID:24704258

Stárka, Luboslav; Dušková, Michaela; Hill, Martin

2015-01-01

285

Age and sex differences in cerebral glucose consumption measured by pet using [18-F] fluorodeoxyglucose (FDG)  

International Nuclear Information System (INIS)

Resting cerebral glucose metabolic rates (CMRglc) were measured in 23 subjects by PET using FDG. Subjects were divided into several groups (mean age +- S.D.) 5 young males (YM) (27 +- 6); 6 young females (YF)(33 +9); 5 elderly males (EM)(73 +- 5); 7 elderly females (EF)(69 +- 7). Additionally, from these groups 4 YM, 3YF, 5EM and 4EF were studied again within 6 weeks under identical conditions. CMRglc in the YF group again was significantly hider than YM (p 0.05). No obvious relationships of CMRglc to the phase of the menstrual cycle was found in this small group. There was a trend (p=0.06) toward a higher CMRglc in YF than EF. These results support the findings of higher CBF in YF versus YM. The differences between the results of Kuhl et al (J. Cereb. and a reduction of CMRglc with age was found in a mixed group of males and females (58and female), and where no age effect was found the males, are also resolved by these findings. The authors suggest that the apparent age effect, in females in this study, is principally a hormonal one

286

Sex ratios  

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Sex ratio theory attempts to explain variation at all levels (species, population, individual, brood) in the proportion of offspring that are male (the sex ratio). In many cases this work has been extremely successful, providing qualitative and even quantitative explanations of sex ratio variation. However, this is not always the situation, and one of the greatest remaining problems is explaining broad taxonomic patterns. Specifically, why do different organisms show so much variation in the ...

West, Sa; Reece, SE; Sheldon, Bc

2002-01-01

287

Electroimmunoassay of sex hormone binding globulin. Enhanced sensitivity by autoradiography using A-ring /sup 125/I-17-. beta. -oestradiol  

Energy Technology Data Exchange (ETDEWEB)

Four different /sup 125/I-iodinated steroids were tested for their binding to human sex hormone binding globulin (SHBG) using an electrophoretic technique. 17-..beta..-oestradiol iodinated in its A-ring bound with high affinity to SHBG. This radioactive steroid was used to increase the sensitivity of the electroimmunoassay of SHBG by adding the steroid to the samples before electroimmunoassay. The radioactive steroid incorporated into the immunoprecipitates could be observed by autoradiography. The sensitivity of the assay, which employed a rabbit antiserum against purified human SHBG and was standardized with pure SHBG, was about 0.2 mg/1. The coefficient of variation within and between assays was 2.4% and 2.6% respectively, for values within the normal range. The mean SHBG concentration in healthy regularly menstruating women was 3.50 +- 0.74 (SD) mg/1 when measured in plasma, and 3.78 +- 0.80 mg/1 when measured in serum. The corresponding mean concentrations in healthy men were 2.26 +- 0.45 and 2.44 +- 0.49 mg/1. The modified electroimmunoassay described is a simple modification, which increases the sensitivity sufficiently to permit reliable quantification of SHBG over the entire range of concentration which could be relevant in clinical practice.

Fernlund, P.; Kjellberg, M. (Lund Univ. (Sweden). Dept. of Clinical Chemistry); Gershagen, S.; Rannevik, G. (Fertility Research Inst., Malmoe (Sweden))

1984-02-01

288

Weakly electric fish as model systems for studying long-term steroid action on neural circuits.  

Science.gov (United States)

Weakly electric fish generate electric organ discharges (EODs) that are species-specific and often sexually-dimorphic. The waveform or frequency of an EOD can be altered by treating a fish with sex steroid hormones. The EOD is controlled by a few discrete nuclei in the brainstem and spinal cord and a muscle-derived electric organ. The organizational simplicity and steroid-sensitivity of the electromotor system make it a premier system for investigating how sex steroids modulate behavior, neural circuitry, and ion channels. In addition, the diversity of EOD patterns in the many species of electric fish provide a wealth of material in which to examine the evolution of sexual dimorphisms in the nervous system. PMID:8252376

Zakon, H H

1993-01-01

289

Transsynaptic trophic effects of steroid hormones in an avian model of adult brain plasticity.  

Science.gov (United States)

The avian song control system provides an excellent model for studying transsynaptic trophic effects of steroid sex hormones. Seasonal changes in systemic testosterone (T) and its metabolites regulate plasticity of this system. Steroids interact with the neurotrophin brain-derived neurotrophic factor (BDNF) to influence cellular processes of plasticity in nucleus HVC of adult birds, including the addition of newborn neurons. This interaction may also occur transsynpatically; T increases the synthesis of BDNF in HVC, and BDNF protein is then released by HVC neurons on to postsynaptic cells in nucleus RA where it has trophic effects on activity and morphology. Androgen action on RA neurons increases their activity and this has a retrograde trophic effect on the addition of new neurons to HVC. The functional linkage of sex steroids to BDNF may be of adaptive value in regulating the trophic effects of the neurotrophin and coordinating circuit function in reproductively relevant contexts. PMID:25285401

Brenowitz, Eliot A

2014-10-01

290

Human sex hormone-binding globulin gene expression- multiple promoters and complex alternative splicing  

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Abstract Background Human sex hormone-binding globulin (SHBG) regulates free sex steroid concentrations in plasma and modulates rapid, membrane based steroid signaling. SHBG is encoded by an eight exon-long transcript whose expression is regulated by a downstream promoter (PL). The SHBG gene was previously shown to express a second major transcript of unknown function, derived from an upstream promoter (PT), and two minor transcripts. Results ...

Rosner William; Hryb Daniel J; Nakhla Atif M; Romas Nicholas A; Xiang Zhaoying; Kahn Scott M

2009-01-01

291

Sex steroids, growth hormone, leptin and the pubertal growth spurt.  

Science.gov (United States)

A normal rate for the linear growth of a child or adolescent is a strong statement for the good general health of that child. Normal growth during childhood is primarily dependent on adequate nutrition, an adequate psychosocial environment, the absence of disease and adequate amounts thyroid hormone and growth hormone (and its downstream product, IGF-1). At adolescence there is the reawakening of the hypothalamic-pituitary-gonadal axis and its interaction with the GH/IGF-1 axis to subserve the pubertal growth spurt. The fat tissue-derived hormone, leptin and its receptor are likely involved in at least two aspects of pubertal development - sexual development itself and the alterations in body composition including the regional distribution of fat and bone mineralization. During the prepubertal years the male female differences in body composition are quite modest, but change remarkably during pubertal development with boys showing a relative decrement in fat percentage and girls a marked increase in concert with rising levels of circulating leptin. The boys show a much greater increase in lean body tissue and the relative proportions of water, muscle and bone. These may be observed as the differential growth of the shoulders and hips. The net effect of these pubertal changes is that the young adult woman has approximately 25% body fat in the 'gynoid' distribution while the male has much more muscle, especially in the shoulders and upper body but only approximately 13% body fat. PMID:19955758

Rogol, Alan D

2010-01-01

292

Does hyperprolactinemia affect hepatic regeneration independent of sex steroids?  

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Prolactin, administered exogenously, has been shown to be trophic to the liver, causing increases in the liver weight–to–body weight ratio, in ornithine decarboxylase activity, and in thymidine kinase activity. To investigate the effect of endogenous hyperprolactinemia on hepatic regeneration, pituitary isografts were placed beneath the renal capsule in rats 2 weeks before the rats underwent a two-thirds partial hepatectomy. Prolactin levels 2 weeks after the transplant were greater in th...

Kahn, D.; Gavaler, J. S.; Makowka, L.; Chapchap, P.; Mazzaferro, V.; Casavilla, A.; Smith, M. S.; Eagon, P. K.; Starzl, T. E.; Thiel, D. H.

1988-01-01

293

Influence of Age and Sex on Body Weight and Some Body Linear Measurements of Extensively Reared Wad Goats in Derived Savannah Zone of Nigeria  

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Body weight and body linear measurement (Diagonal body length, Height-at-withers, sac pelvic width, Heart girth) of 259 West African Dwarf (WAD) goats (both sexes) in three age groups (Kid, yearling and Adult) were measured. The least square means for body weight were 6.40, 10.5 and 18.9 kg for kid, yearling and Adult respectively. Means of other body linear measurements also vary within each age group. The variables measured vary positively with age of the animals and the correlatio...

Ojedapo, L. O.; Adedeji, T. A.; Olayeni, T. B.; Adedeji, O. S.; Abdullah, A. R.; Ojebiyi, O. O.

2007-01-01

294

BILATERAL STEROID INDUCED GLAUCOMA IN VERNAL KERATOCONJUNCTIVITIS  

Directory of Open Access Journals (Sweden)

Full Text Available Vernal Keratoconjunctivits (VKC is a bilateral recurrent allergic interstitial conjunctival inflammation with a periodic seasonal incidence and of self limiting nature, mainly affecting the younger population. Patients of VKC on steroid therapy are at higher risk of developing steroid induced glaucoma. Raised intraocular pressure due to steroids typically occurs within few weeks of starting steroid therapy and comes back to normal on immediate stoppage of steroids. A case of steroid induced glaucoma in a 30 years old female with vernal keratoconjunctivitis. She was on topical steroids for 3-4 years. She was incompliant with the instructions to stop steroids. She eventually developed steroid induced glaucoma and glaucomatous optic neuropathy with tunnel vision.

Bangal Surekha V, Bankar Mahima S, Bhandari Akshay J, Kalkote Prasad R

2015-01-01

295

Steroidal saponins from Smilax officinalis.  

Science.gov (United States)

Three new steroidal saponins were isolated from the rhizomes of Smilax officinalis. The structures of these saponins were established by extensive spectral data, hydrolysis and chemical correlation as sarsasapogenin 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )-beta- D-glucopyranoside, neotigogenin 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )]-beta- D-glucopyranoside and 25S-spirostan-6 beta-ol 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )]-beta- D-glucopyranoside. Acid hydrolysis of the latter compound gave a sapogenin which has a new orientation of an hydroxyl on the steroidal skeleton. A route is proposed for the biogenesis of the latter sapogenin which is an uncommon steroidal aglycone. PMID:8862038

Bernardo, R R; Pinto, A V; Parente, J P

1996-09-01

296

Neuroactive steroids and central nervous system disorders.  

Science.gov (United States)

Steroid hormones are vital for the cell life and affect a number of neuroendocrine and behavioral functions. In contrast to their endocrine actions, certain steroids have been shown to rapidly alter brain excitability and to produce behavioral effects within seconds to minutes. In this article we direct attention to this issue of neuroactive steroids by outlining several aspects of current interest in the field of steroid research. Recent advances in the neurobiology of neuroactive are described along with the impact of advances on drug design for central nervous system (CNS) disorders provoked by neuroactive steriods. The theme was selected in association with the clinical aspects and therapeutical potentials of the neuroactive steroids in CNS disorders. A wide range of topics relating to the neuroactive steroids are outlined, including steroid concentrations in the brain, premenstrual syndrome, estrogen and Alzheimer's disease, side effects of oral contraceptives, mental disorder in menopause, hormone replacement therapy, Catamenial epilepsy, and neuractive steroids in epilepsy treatment. PMID:11599309

Wang, M; Bäckström, T; Sundström, I; Wahlström, G; Olsson, T; Zhu, D; Johansson, I M; Björn, I; Bixo, M

2001-01-01

297

Steroid Injections for the Carpal Tunnel Syndrome  

Science.gov (United States)

Steroid Injections for the Carpal Tunnel Syndrome The full report is titled “Methylprednisolone Injections for the Carpal ... treatment is wrist splinting. When splinting is ineffective, steroid injections are often given and provide relief. However, ...

298

Teens and Steroids: A Dangerous Combo  

Science.gov (United States)

... Vaccines, Blood & Biologics Articulos en Espanol Teens and Steroids: A Dangerous Combo Search the Consumer Updates Section ... to know how dangerous it is to use steroids in hopes of being better athletes or more ...

299

Permanent and functional male-to-female sex reversal in d-rR strain medaka (Oryzias latipes) following egg microinjection of o,p'-DDT.  

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Complete sex reversal of fish is accomplished routinely in aquaculture practices by exposing fish to exogenous sex steroids during gonadal differentiation. A variety of environmental chemicals are also active at sex steroid receptors and theoretically possess the potential to alter normal sexual differentiation in fish. However, in controlled environmental chemical exposures to date, only partial alterations of fish sexual phenotype have been observed. Here we report complete, permanent, and ...

Edmunds, J. S.; Mccarthy, R. A.; Ramsdell, J. S.

2000-01-01

300

Steroidal glycoalkaloids in Solanum chacoense.  

Science.gov (United States)

Potato (Solanum tuberosum L.), a domesticated species that is the fourth most important world agricultural commodity, requires significant management to minimize the effects of herbivore and pathogen damage on crop yield. A wild relative, Solanum chacoense Bitt., has been of interest to plant breeders because it produces an abundance of novel steroidal glycoalkaloid compounds, leptines and leptinines, which are particularly effective deterrents of herbivory by the Colorado potato beetle (Leptinotarsa decemlineata Say). Biochemical approaches were used in this study to investigate the formation and accumulation of SGAs in S. chacoense. SGA contents were determined in various organs at different stages of organ maturity during a time course of plant development. Leptines and leptinines were the main contributors to the increased levels in SGA concentration measured in the aerial versus the subterranean organs of S. chacoense accession 8380-1. Leptines were not detected in aboveground stolons until the stage where shoots had formed mature chlorophyllous leaves. To gain insights into SGA biosynthesis, the abundance of SGAs and steady-state transcripts of genes coding for enzymes of the central terpene and SGA-specific pathways in various plant organs at anthesis were compared. For two genes of primary terpene metabolism, transcript and SGA abundances were correlated, although with some discrepancies. For genes associated with SGA biosynthesis, transcripts were not detected in some tissues containing SGAs; however these transcripts were detected in the progenitor tissues, indicating the possibility that under our standard growth conditions, SGA biosynthesis is largely limited to highly proliferative tissues such as shoot, root and floral meristems. PMID:22217745

Mweetwa, Alice M; Hunter, Danielle; Poe, Rebecca; Harich, Kim C; Ginzberg, Idit; Veilleux, Richard E; Tokuhisa, James G

2012-03-01

 
 
 
 
301

MEDICAL ISSUES ASSOCIATED WITH ANABOLIC STEROID USE: ARE THEY EXAGGERATED?  

Directory of Open Access Journals (Sweden)

Full Text Available For the past 50 years anabolic steroids have been at the forefront of the controversy surrounding performance enhancing drugs. For almost half of this time no attempt was made by sports governing bodies to control its use, and only recently have all of the major sports governing bodies in North America agreed to ban from competition and punish athletes who test positive for anabolic steroids. These punitive measures were developed with the primary concern for promotion of fair play and eliminating potential health risks associated with androgenic-anabolic steroids. Yet, controversy exists whether these testing programs deter anabolic steroid use. Although the scope of this paper does not focus on the effectiveness of testing, or the issue of fair play, it is of interest to understand why many athletes underestimate the health risks associated from these drugs. What creates further curiosity is the seemingly well-publicized health hazards that the medical community has depicted concerning anabolic steroidabuse. Is there something that the athletes know, or are they simply naïve regarding the dangers? The focus of this review is to provide a brief history of anabolic steroid use in North America, the prevalence of its use in both athletic and recreational populations and its efficacy. Primary discussion will focus on health issues associated with anabolic steroid use with an examination of the contrasting views held between the medical community and the athletes that are using these ergogenic drugs. Existing data suggest that in certain circumstances the medical risk associated with anabolic steroid use may have been somewhat exaggerated, possibly to dissuade use in athletes

Jay R. Hoffman

2006-06-01

302

Safe sex  

Science.gov (United States)

There are many diseases that humans can contract through sexual contact with each other. Humans can lower their risk of contracting these diseases by practicing safe sex techniques if they choose to participate in those kinds of actions.

Olivia Worland (Purdue University;Biological Sciences)

2008-07-09

303

Anabolic Steroid Use in the Adolescent Athlete  

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Recent surveys indicate that the use of androgenic-anabolic steroids (anabolic steroids) is prevalent among adolescent athletes, particularly those in high school. The cost of clinical drug testing makes it impractical to use random testing to identify users of these ergogenic aids. The athletic trainer is often in a position to identify anabolic steroid users if he/she knows the clinical signs and symptoms. In this article, we briefly discuss the history of anabolic steroid use, how they wor...

Potteiger, Jeffrey A.; Stilger, Vincent G.

1994-01-01

304

Condom Use at Last Sex as a Proxy for Other Measures of Condom Use: Is It Good Enough?  

Science.gov (United States)

Condom use at last sex is a widely used indicator in sexual behavior research; however, there is little empirical research validating this indicator. This study examined whether a single-event recall period (the last time coitus occurred) was consistent with longer recall periods (14 days and 60 days) for a sample of African American adolescent…

Younge, Sinead N.; Salazar, Laura F.; Crosby, Richard F.; DiClemente, Ralph J.; Wingood, Gina M.; Rose, Eve

2008-01-01

305

Steroidal glycosides from tubers of Ophiopogon japonicus.  

Science.gov (United States)

A new steroidal saponin, named ophiopogonin E (1), has been isolated from the tubers of Ophiopogon japonicus, along with five known steroidal saponins (2-6). The structure of the new steroidal glycoside was characterized by spectroscopic analysis and acid-catalyzed hydrolysis as pennogenin 3-O-beta-D-xylopyranosyl (1 --> 4)-beta-D-glucopyranoside (1). PMID:16931432

Cheng, Z-H; Wu, T; Yu, B-Y

2006-09-01

306

Adolescents and Steroids: A User Perspective.  

Science.gov (United States)

Anabolic-androgenic steroids ("steroids") are synthetic derivatives of the natural male hormone testosterone. They were first used non-medically by elite athletes seeking to improve performance. More recently, however, steroid use has filtered down to high school and junior high school levels. The purpose of this study was to describe adolescent…

Office of Inspector General (DHHS), Washington, DC.

307

How Steroids Steer T Cells  

Directory of Open Access Journals (Sweden)

Full Text Available Recent papers from Mahata et al. and Bereshchenko et al. reveal how steroids steer immune responses by tipping T helper (Th subset balances and activities. Pregnenolone produced by Th2 cells mediates immunosuppressive responses, and glucocorticoids stimulate regulatory T cell development via the induction of GILZ expression.

Claude Libert

2014-05-01

308

Sexing of human hip bones.  

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Eight measurements of the hipbone were taken from 62 human skeletons of unknown sex. The subjective judgements of eight experienced anatomists were used to obtain subsets of male, female and unknown sex specimens. Principal components analysis was employed as a group-finding procedure; this confirmed the subjective determinations. Discriminant function analysis, using the subjectively determined 'known' specimens, was conducted. This yielded scores which sexed the unknown subset in agreement ...

Milne, N.

1990-01-01

309

The relationship between plasma steroid hormone concentrations and the reproductive cycle in the Northern Pacific rattlesnake, Crotalus oreganus.  

Science.gov (United States)

We describe the reproductive cycle of Northern Pacific rattlesnakes (Crotalus oreganus) by quantifying steroid hormone concentrations and observing reproductive behaviors in free-ranging individuals. Additionally, we examined reproductive tissues from museum specimens. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (March-October). We measured testosterone (T), 5alpha-dihydrotestosterone (DHT), and corticosterone (B) concentrations in both sexes and 17beta-estradiol (E2) and progesterone (P) in females only. We observed reproductive behaviors (e.g., consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections to relate steroid hormone concentrations to the timing of reproductive events. Our study revealed that C. oreganus in central California exhibits a bimodal pattern of breeding, with most mating behavior occurring in the spring and some incidences of mating behavior observed in late summer/fall. Each breeding period corresponded with elevated androgen (T or DHT) levels in males. Testes were regressed in the spring when the majority of reproductive behavior was observed in this population, and they reached peak volume in August and September during spermatogenesis. Although we did not detect seasonal variation in female hormone concentrations, some females had high E2 in the spring and fall, coincident with mating and with increased follicle size (indicating vitellogenesis) in museum specimens. Females with high E2 concentrations also had high T and DHT concentrations. Corticosterone concentrations in males and females were not related either to time of year or to concentrations of any other hormones quantified. Progesterone concentrations in females also did not vary seasonally, but this likely reflected sampling bias as females tended to be underground, and thus unobtainable, in summer months when P would be expected to be elevated during gestation. In females, P was positively correlated with T and DHT, and E2 was positively correlated with T. PMID:20138180

Lind, Craig M; Husak, Jerry F; Eikenaar, Cas; Moore, Ignacio T; Taylor, Emily N

2010-05-01

310

Pathways to ischemic neuronal cell death: are sex differences relevant?  

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Abstract We have known for some time that the epidemiology of human stroke is sexually dimorphic until late in life, well beyond the years of reproductive senescence and menopause. Now, a new concept is emerging: the mechanisms and outcome of cerebral ischemic injury are influenced strongly by biological sex as well as the availability of sex steroids to the brain. The principal mammalian estrogen (17 ? estradiol or E2) is neuroprotective in many types of brain in...

McCullough Louise D; Lang Jesse T

2008-01-01

311

Sex differences in response to adrenocorticotropin (ACTH) administration in sheep  

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This thesis summarises and discusses results of two separate studies on the effects of adrenocorticotropin (ACTH) on the secretion of steroid hormones in sheep of different sex and gonadal status. Furthermore, it includes a study on the effects of ACTH and progesterone on luteinising hormone (LH) secretion in castrated rams as well as a study on sex differences in oestrogen receptor (ER) content of adrenal glands of sheep. Testosterone concentrations of castrated males before and after ACTH a...

Lier, Elize

2003-01-01

312

Steroid radioimmunoassay: contribution of standards to blank values, ch. 4  

International Nuclear Information System (INIS)

The sensitivity of the radioimmunoassay of steroids is considerably reduced by high blank values which may be derived in part from co-chromatographed standards. Blank levels approach the detection limit of the radioimmunoassay of aldosterone, testosterone and androstenedione when 10,000 dpm (30-35 pg) labelled steroids are used as reference standard. When 20 ?g aldosterone, testosterone, or androstenedione is used as standard, blank levels of up to 12,800 pg were measured in the radioimmunoassay. Application of the standards on a separate strip does not improve the results. From the experiments it appeared that contamination took place by transport by the solvent

313

Multiple steroid radioimmunoassays and automation: versatile techniques for reproductive endocrinology  

International Nuclear Information System (INIS)

The combination of the efficient steroid separating properties of a lipophilic Sephadex derivative Lipidex-5000sup(TM), with the use of antibodies with carefully selected specificity allows the quantitative determination of pregnenolone, progesterone, 17?-hydroxyprogesterone, androstenedione, testosterone, 5?-dihydrotestosterone, 5?-androstanedione, androsterone and 5?-androstane-3?, 17?-diol from 1-2 ml samples of blood serum, amniotic fluid or 300-600 mg pieces of prostatic tissue. The adaptation of the pipetting unit and incubator of a discrete clinical chemical analyzer, System Olli 3000, for the automation of the radioimmunoassays has resulted in a greatly increased through-put and decreased experimental error of the procedure. In studies on reproductive endocrinology, the methodology developed has allowed the detection of a sex difference in androgen composition of the amniotic fluid early in pregnancy. Further, it is very likely that the decline in steroid production by the testis seen during the first year of life and then in senescence is affected by basically different mechanisms. There are also important differences in the steroid content of normal, hyperplastic and carcinomatous prostate. (orig.)

314

[Plasma dehydroepiandrosterone sulfate and urine steroid excretion in hepatic cirrhosis].  

Science.gov (United States)

In the present study we evaluated the alterations of plasma levels of dehydroepiandrosterone sulphate (DHEA-S) and of steroid-derivatives urinary excretion in cirrhotic patients compared with normal controls. 107 patients have been studied: 45 affected by liver cirrhosis (22 males and 23 females) both in compensated and in ascitic state, and 62 healthy controls (32 males and 30 females). In all patients we assayed plasma DHEA-S by RIA as well as common liver function tests; moreover gaschromatographic profile of adrenal steroid excretion was performed in daily urine. Our findings show a significantly lower DHEA-S in cirrhotic patients compared with healthy controls, both males (451.7 SD 440.3 ng/ml vs 1438.3 SD 604.8, p less than 0.001) and females (225.5 SD 152.6 ng/ml vs 974.0 SD 405.7, p less than 0.001). Variance analysis confirmed that the difference was significant both for compensated and uncompensated ones. We also found some interesting relationships between DHEA-S and liver function tests, cholesterol and age. Urinary steroids were markedly low in both sexes, particularly adrenal sexual fraction. Our data show clear disfunction in DHEA-S metabolism in liver cirrhosis, partially related with the severity of the disease. PMID:2523552

Capra, F; Casaril, M; Stanzial, A M; Gabrielli, G B; Marsilli, R; Ferrari, S; Corrocher, R

1989-01-01

315

Modulation of follistatin and myostatin propeptide by anabolic steroids and gender.  

Science.gov (United States)

The purpose of this pilot study was to investigate the impact of training, anabolic steroids and endogenous hormones on myostatin-interacting proteins in order to identify manipulations of myostatin signalling. To identify whether analysis of the myostatin interacting proteins follistatin and myostatin propeptide is suitable to detect the abuse of anabolic steroids, their serum concentrations were monitored in untrained males, bodybuilders using anabolic steroids and natural bodybuilders. In addition, we analysed follistatin and myostatin propeptide serum proteins in females during menstrual cycle. Our results showed increased follistatin concentrations in response to anabolic steroids. Furthermore, variations of sex steroid levels during the menstrual cycle had no impact on the expression of follistatin and myostatin propetide. In addition, we identified gender differences in the basal expression of the investigated proteins. In general, follistatin and myostatin propeptide concentrations were relatively stable within the same individual both in males and females. In conclusion, the current findings provide an insight into gender differences in myostatin-interacting proteins and their regulation in response to anabolic steroids and endogenous hormones. Therefore our data provide new aspects for the development of doping prevention strategies. PMID:23559411

Mosler, S; Geisler, S; Hengevoss, J; Schiffer, T; Piechotta, M; Adler, M; Diel, P

2013-07-01

316

Steroid derivatives and their use in radioimmunoassays  

International Nuclear Information System (INIS)

Radioimmunoassay techniques have been used to determine the concentration in body fluids of various endogenous and exogenous steroids. In the development of radioimmunoassays for the various steroids, the preparation of an antigen labelled with iodine-125 is of primary concern. The chemical structure of steroids is such that it is generally not possible to radioiodinate them directly. It is necessary to utilize as a precursor of the radiolabeled antigen a derivative of the steroid to be assayed which can be readily iodinatd. The process by which steroids are chosen and structurally modified is given

317

Sex hormones alter sex ratios in the Indian skipper frog, Euphlyctis cyanophlyctis: Determining sensitive stages for gonadal sex reversal.  

Science.gov (United States)

In amphibians, although genetic factors are involved in sex determination, gonadal sex differentiation can be modified by exogenous steroid hormones suggesting a possible role of sex steroids in regulating the process. We studied the effect of testosterone propionate (TP) and estradiol-17? (E2) on gonadal differentiation and sex ratio at metamorphosis in the Indian skipper frog, Euphlyctis cyanophlyctis with undifferentiated type of gonadal differentiation. A series of experiments were carried out to determine the optimum dose and sensitive stages for gonadal sex reversal. Our results clearly indicate the importance of sex hormones in controlling gonadal differentiation of E. cyanophlyctis. Treatment of tadpoles with 10, 20, 40, and 80?g/L TP throughout larval period resulted in the development of 100% males at metamorphosis at all concentrations. Similarly, treatment of tadpoles with 40?g/L TP during ovarian and testicular differentiation resulted in the development of 90% males, 10% intersexes and 100% males respectively. Treatment of tadpoles with 10, 20, 40, and 80?g/L E2 throughout larval period likewise produced 100% females at all concentrations. Furthermore, exposure to 40?g/L E2 during ovarian and testicular differentiation produced 95% females, 5% intersexes and 91% females, 9% intersexes respectively. Both TP and E2 were also effective in advancing the stages of gonadal development. Present study shows the effectiveness of both T and E2 in inducing complete sex reversal in E. cyanophlyctis. Generally, exposure to E2 increased the larval period resulting in significantly larger females than control group while the larval period of control and TP treated groups was comparable. PMID:24815042

Phuge, S K; Gramapurohit, N P

2014-05-01

318

Comprehensive Analysis of Hormone and Genetic Variation in 36 Genes Related to Steroid Hormone Metabolism in Pre- and Postmenopausal Women from the Breast and Prostate Cancer Cohort Consortium (BPC3)  

Science.gov (United States)

Context: Sex steroids play a central role in breast cancer development. Objective: This study aimed to relate polymorphic variants in 36 candidate genes in the sex steroid pathway to serum concentrations of sex steroid hormones and SHBG. Design: Data on 700 genetic polymorphisms were combined with existing hormone assays and data on breast cancer incidence, within the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Nurses' Health Study (NHS) cohorts; significant findings were reanalyzed in the Multiethnic Cohort (MEC). Setting and Participants: We analyzed data from a pooled sample of 3852 pre- and postmenopausal Caucasian women from EPIC and NHS and 454 postmenopausal women from MEC. Main Outcome Measures: Outcome measures were SHBG, testosterone, dehydroepiandrosterone (DHEAS), androstenedione, estrone (E1), and estradiol (E2) as well as breast cancer risk. Results: Globally significant associations were found among pre- and postmenopausal women combined between levels of SHBG and the SHBG gene and between DHEAS and the FSHR and AKR1C3 genes. Among postmenopausal women, serum E1 and E2 were significantly associated with the genes CYP19 and FSHR, and E1 was associated with ESR1. None of the variants related to serum hormone levels showed any significant association with breast cancer risk. Conclusions: We confirmed associations between serum levels of SHBG and the SHBG gene and of E1 and E2 and the CYP19 and ESR1 genes. Novel associations were observed between FSHR and DHEAS, E1, and E2 and between AKR1C3 and DHEAS. PMID:21177793

Beckmann, L.; Hüsing, A.; Setiawan, V. W.; Amiano, P.; Clavel-Chapelon, F.; Chanock, S. J.; Cox, D. G.; Diver, R.; Dossus, L.; Feigelson, H. S.; Haiman, C.; Hallmans, G.; Hayes, R. B.; Henderson, B. E.; Hoover, R. N.; Hunter, D. J.; Khaw, K.; Kolonel, L. N.; Kraft, P.; Lund, E.; Le Marchand, L.; Peeters, P. H. M.; Riboli, E.; Stram, D.; Thomas, G.; Thun, M. J.; Tumino, R.; Trichopoulos, D.; Vogel, U.; Willett, W. C.; Yeager, M.; Ziegler, R.; Hankinson, S. E.

2011-01-01

319

Comprehensive Analysis of Hormone and Genetic Variation in 36 Genes Related to Steroid Hormone Metabolism in Pre- and Postmenopausal Women from the Breast and Prostate Cancer Cohort Consortium (BPC3)  

DEFF Research Database (Denmark)

Context: Sex steroids play a central role in breast cancer development.Objective: This study aimed to relate polymorphic variants in 36 candidate genes in the sex steroid pathway to serum concentrations of sex steroid hormones and SHBG.Design: Data on 700 genetic polymorphisms were combined with existing hormone assays and data on breast cancer incidence, within the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Nurses' Health Study (NHS) cohorts; significant findings were reanalyzed in the Multiethnic Cohort (MEC).Setting and Participants: We analyzed data from a pooled sample of 3852 pre- and postmenopausal Caucasian women from EPIC and NHS and 454 postmenopausal women from MEC.Main Outcome Measures: Outcome measures were SHBG, testosterone, dehydroepiandrosterone (DHEAS), androstenedione, estrone (E1), and estradiol (E2) as well as breast cancer risk.Results: Globally significant associations were found among pre- and postmenopausal women combined between levels of SHBG and theSHBG gene and between DHEAS and the FSHR and AKR1C3 genes. Among postmenopausal women, serum E1 and E2 were significantly associated with the genes CYP19 and FSHR, and E1 was associated with ESR1. None of the variants related to serum hormone levels showed any significant association with breast cancer risk.Conclusions: We confirmed associations between serum levels of SHBG and the SHBG gene and of E1 and E2 and the CYP19 and ESR1 genes. Novel associations were observed between FSHR and DHEAS, E1, and E2 and between AKR1C3 and DHEAS. (J Clin Endocrinol Metab 96: E360-E367, 2011)

Beckmann, L.; Husing, A.

2011-01-01

320

Chemosensory communication of gender through two human steroids in a sexually dimorphic manner.  

Science.gov (United States)

Recent studies have suggested the existence of human sex pheromones, with particular interest in two human steroids: androstadienone (androsta-4,16,-dien-3-one) and estratetraenol (estra-1,3,5(10),16-tetraen-3-ol). The current study takes a critical step to test the qualification of the two steroids as sex pheromones by examining whether they communicate gender information in a sex-specific manner. By using dynamic point-light displays that portray the gaits of walkers whose gender is digitally morphed from male to female [1, 2], we show that smelling androstadienone systematically biases heterosexual females, but not males, toward perceiving the walkers as more masculine. By contrast, smelling estratetraenol systematically biases heterosexual males, but not females, toward perceiving the walkers as more feminine. Homosexual males exhibit a response pattern akin to that of heterosexual females, whereas bisexual or homosexual females fall in between heterosexual males and females. These effects are obtained despite that the olfactory stimuli are not explicitly discriminable. The results provide the first direct evidence that the two human steroids communicate opposite gender information that is differentially effective to the two sex groups based on their sexual orientation. Moreover, they demonstrate that human visual gender perception draws on subconscious chemosensory biological cues, an effect that has been hitherto unsuspected. PMID:24794295

Zhou, Wen; Yang, Xiaoying; Chen, Kepu; Cai, Peng; He, Sheng; Jiang, Yi

2014-05-19

 
 
 
 
321

Comparison of steroid pulse therapy and conventional oral steroid therapy as initial treatment for autoimmune pancreatitis  

International Nuclear Information System (INIS)

The efficacy of oral steroid therapy for autoimmune pancreatitis (AIP) is well known, and oral prednisolone treatment is most usually commenced at 30-40 mg/day, but there have been few reports about comparative studies of oral steroid therapy and steroid pulse therapy as the initial treatment for AIP. We studied the clinical course and image findings to estimate the utility of steroid pulse therapy for AIP, comparing it with oral steroid therapy. Laboratory and image findings were assessed retrospectively in 11 patients who received steroid pulse therapy, and the findings were compared to those in 10 patients who received conventional oral steroid therapy. Change in pancreatic size showed no significant difference between the therapies after 2 weeks of treatment. Significant improvement of lower bile duct strictures after 2 weeks of treatment and that of immunoglobulin values within 6 months were shown with both therapies. However, steroid pulse therapy showed significant improvement of ?-guanosine triphosphate (GTP) in 2 weeks and of alanine aminotransferase (ALT) in 2 and 8 weeks, compared with oral steroid therapy. Moreover, there was one patient in whom the lower bile duct stricture was not improved by oral steroid therapy, but it did show improvement with steroid pulse therapy. Initial steroid pulse therapy is a beneficial alternative to oral steroid therapy for the improvement of bile duct lesions. In future, the accumulation of a larger number of patients receation of a larger number of patients receiving steroid pulse therapy is needed, and prospective studies will be required. (author)

322

Steroids reduce complement activation in rheumatoid arthritis.  

Science.gov (United States)

Patients with seropositive, classical rheumatoid arthritis (RA) with severe active disease have raised plasma concentrations of the complement C3 split product C3d. These values display little diurnal or circadian variation in the individual patient. During a 3-month period the variation was within 10 mU/l in 45 patients (ref. range 20-52 mU/l, RA patients up to 120 mU/l.) Six RA patients were treated with steroids on clinical indication, and the plasma C3d, Ritchie index and pain score before and during the treatment (30 mg prednisolone per day) were measured. The variables showed a steady decrease during the next 14 days. Plasma C3d fell 2/3 of the total fall within the first 48 hours, while the serum total haemolytic complement activity, complement C3 and C4 did not change significantly. This shows that the anti-inflammatory effect of steroids is accompanied by a reduction of complement activation. PMID:3875589

Brandslund, I; Peters, N D; Ejstrup, L

1985-01-01

323

Vibrational properties and phonon anharmonicity in ZnS1?xSex: Inelastic neutron scattering, Raman scattering, X-ray diffraction measurements and lattice dynamical studies  

International Nuclear Information System (INIS)

Inelastic neutron scattering, Raman and X-ray diffraction measurements coupled with lattice dynamical calculations (employing a semi-empirical transferable potential model) have been carried out to gain a detailed understanding of the peculiar vibrational spectrum exhibited by the mixed crystal ZnS1?xSex. Raman scattering measurements performed over a varying range of temperature (100–800 K) and pressure (up to 13 GPa) have confirmed that the additional mode observed in the spectra are visible over the entire range of temperature and pressure. Correlation of the individual motions of atoms (obtained from computed total and partial phonon density of states) with the inelastic neutron scattering measurements (carried out over the entire Brillouin zone) have then indicated that the existence of the additional mode in ZnS1?xSex is due to the vibrations of the Se atom being in resonance with that of the S atom. Further, it has been shown that the presence of this additional mode can be tuned by varying the mass of the atom at the Se site. In addition, an analysis of bond-length distribution with increasing Se concentration have elucidated that bond-length spread is not responsible for the presence of the additional mode. An analysis of the peak shifts of the Raman modes with temperature and pressure indicate that the anharmonicity of the vibrational modes increases with increasing compositional disorder. This is attributed to the fact that increasing Se concentration gives rise to a distribution of bond-lengths in ZnS1?xSex, which is responsible for this compositional disorder induced anharmonicity. Our computations have thus revealed that mass of the anion is responsible for the presence of additional mode while bond-length distribution gives rise to the existence of compositional disorder induced anharmonicity in ZnS1?xSex. Further, it is observed that the contribution of explicit anharmonicity to the total anharmonicity becomes dominant at higher temperatures. This compound also exhibits negative thermal expansion at low temperatures as obtained from our X-ray diffraction measurements as a function of temperature (10–800 K)

324

The Effect of Type of Birth, Sex and Castration on Body Weight and Body Linear Measurements in Pre-Weaning Kids  

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This study was conducted to determine the effect of castration, sex and type of birth on the rate of body weight gain and linear measurements non castrates, castrates and female Savanna Brown kids. The mean values of the body weight, body length and chest girth of single non-castrates (5.75kg, 53.37 cm and 42.50cm) were higher but not significantly different (p > 0.05) from other groups. Single castrates and twin castrates in height at withers (38.86cm and 38.47cm), significantly (p < 0...

Adama, T. Z.; Tsado, D. N.

2012-01-01

325

Steroidal saponins from Asparagus racemosus.  

Science.gov (United States)

Two new steroidal saponins, shatavaroside A (1) and shatavaroside B (2) together with a known saponin, filiasparoside C, were isolated from the roots of Asparagus racemosus. Filiasparoside C was first time isolated from this plant. Their structures were elucidated by 1D and 2D NMR experiments including correlation spectroscopy, distortionless enhancement by polarization transfer, heteronuclear multiple quantum correlation and heteronuclear multiple bond coherence spectroscopy as well as electrospray ionization-QTOF-MS/MS analysis. PMID:19652422

Sharma, Upendra; Saini, Rikki; Kumar, Neeraj; Singh, Bikram

2009-08-01

326

Radioimmunoassay for steroid hormones, 3  

International Nuclear Information System (INIS)

A specific, sensitive and reliable radioimmunoassay for plasma dehydroepiandrosterone (DHEA) has been developed. Anti-DHEA serum was obtained by immunizing rabbits with a DHEA-3-hemisuccinate-BSA conjugate. A useful range in the standard curve was from 10 pg to 500 pg. DHEA was separated from cross-reacting steroids by microcolumn chromatography. The coefficients of variation for within-assay and between-assay are 6.3% and 7.7%, respectively. (auth.)

327

ABUSE OF ANABOLIC ANDROGENIC STEROIDS  

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According to the International Olympic Committee, the abuse of anabolic androgenic steroids (AASS) is found in over 50% of positive doping tests. AASS abuse is not restricted to the organized sports andwidespread use. It remains as an unsolved public-health problem.Lower black market price, easier access to AASS, bodybuilding clubs and internet advertising are factors of this increasingly misuse. There is not real data about the prevalence of AASS abuse in various populations or countries, be...

Abbas Yavari

2009-01-01

328

Steroidal saponins from Asparagus acutifolius.  

Science.gov (United States)

Six new steroidal saponins (1-6) were isolated from the roots of A. acutifolius L., together with a known spirostanol glycoside (7). Their structures were elucidated mainly by extensive spectroscopic analysis (1D and 2D NMR, FABMS and HRESIMS). Compounds 4-7 demonstrated antifungal activity against the human pathogenic yeasts C. albicans, C. glabrata and C. tropicalis with MICs values between 12.5 and 100 microg/ml. PMID:17449075

Sautour, Marc; Miyamoto, Tomofumi; Lacaille-Dubois, Marie-Aleth

2007-10-01

329

Steroids, triterpenoids and molecular oxygen  

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There is a close connection between modern-day biosynthesis of particular triterpenoid biomarkers and presence of molecular oxygen in the environment. Thus, the detection of steroid and triterpenoid hydrocarbons far back in Earth history has been used to infer the antiquity of oxygenic photosynthesis. This prompts the question: were these compounds produced similarly in the past? In this paper, we address this question with a review of the current state of knowledge surrounding the oxygen req...

Summons, Roger E.; Bradley, Alexander S.; Jahnke, Linda L.; Waldbauer, Jacob R.

2006-01-01

330

Measurements of the frontal and prefrontal lobe volumes by three dimensional magnetic resonance imaging scan. III. Analysis of sex differences with advanced age  

International Nuclear Information System (INIS)

To determine whether there is sex difference in the growth of the frontal and prefrontal lobes, we quantitatively measured the volume of these lobes by three dimensional (3-D) MRI in healthy 12 males (5 months to 39 years) and six females (1 year 11 months to 27 years). The left and right lobes were studied separately. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5 T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. In males, the left to right ratio (L/R ratio) of the frontal and prefrontal lobes increased with age. On the contrary, in females, L/R ratio of the frontal and prefrontal lobes showed no significant change with advancing age. These results highlighted sex-specific maturational changes of the frontal and prefrontal lobes and suggested that quantitative data on the frontal and prefrontal lobe are important in interpreting brain abnormalities in children with developmental disorders. (author)

331

Modulation of Xenobiotic Receptors by Steroids  

Directory of Open Access Journals (Sweden)

Full Text Available Nuclear receptors (NRs are ligand-activated transcription factors that regulate the expression of their target genes. NRs play important roles in many human diseases, including metabolic diseases and cancer, and are therefore a key class of therapeutic targets. Steroids play important roles in regulating nuclear receptors; in addition to being ligands of steroid receptors, steroids (and their metabolites also regulate other NRs, such as the pregnane X receptor and constitutive androstane receptor (termed xenobiotic receptors, which participate in steroid metabolism. Xenobiotic receptors have promiscuous ligand-binding properties, and their structurally diverse ligands include steroids and their metabolites. Therefore, steroids, their metabolism and metabolites, xenobiotic receptors, steroid receptors, and the respective signaling pathways they regulate have functional interactions. This review discusses these functional interactions and their implications for activities mediated by steroid receptors and xenobiotic receptors, focusing on steroids that modulate pathways involving the pregnane X receptor and constitutive androstane receptor. The emphasis of the review is on structure-function studies of xenobiotic receptors bound to steroid ligands.

Delira Robbins

2013-06-01

332

Differentiation of endogenous and exogenous steroids by gas chromatography-combustion-mass spectrometry isotope ratio  

International Nuclear Information System (INIS)

Urinary steroids profiles are used to control the misuse of endogenous steroids such as testosterone and dihydrotestosterone. The testosterone/epistestosterone ratio, measured by Gas Chromatography-Mass Spectrometry, is used to control testosterone administration. When T/E ratio is higher than 4, consumption of testosterone or its precursors is suspected. Recent researches have demonstrated the effectiveness of Carbon Isotope Ratio Mass Spectrometry to detect and confirm endogenous steroids administration. The ratio of the two stable carbon isotopes 13C and 12C allows the differentiation of natural and synthetic steroids because synthetic steroids have lower 13C abundance. In fact, the carbon isotope ratios can be used to determine endogenous steroids administration even when testosterone/epistestosterone ratio is at its normal value. In the current work, some of the most important aspects related to differentiation of endogenous and exogenous steroids by means of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry are discussed. Also, this article provides a review about the purification and sample preparation previous to the analysis, and diet effects on carbon isotope ratio of endogenous anabolics steroids is presented too

333

The brain of teleost fish, a source and a target of sexual steroids  

Directory of Open Access Journals (Sweden)

Full Text Available Neurosteroids are defined as steroids de novo synthesized in the central nervous system. While the production of neurosteroids is well documented in mammals or amphibians, there is little information in teleosts, the largest group of fish. Teleosts have long been known for their high brain aromatase and 5?-reductase activities, but recent data now document the capacity of the brain of fish to produce a large variety of sex steroids. This article aims at reviewing the available information regarding expression and/or activity of the main steroidogenic enzymes in the brain of fish. In addition, the distribution of estrogen, androgen and progesterone nuclear receptors is documented in relation with the potential sites of production of neurosteroids. Interestingly, radial glial cells acting as neuronal progenitors, appear to be a potential source of neurosteroids, but also a target for centrally and/or peripherally produced steroids.

OlivierKah

2011-12-01

334

Sex during Pregnancy  

Science.gov (United States)

... satisfying and safe sexual relationship during pregnancy. Is Sex During Pregnancy Safe? Sex is considered safe during ... frequently asked questions about sex during pregnancy. Can sex harm my baby? No. Your baby is fully ...

335

Altered Serum Lipoprotein Profiles in Male and Female Power Lifters Ingesting Anabolic Steroids.  

Science.gov (United States)

Serum lipoprotein profiles were measured in nine male and three female weightlifters who were taking anabolic steroids. The profiles suggest that steriod users may face an increased risk of coronary artery disease. (Author/MT)

Cohen, Jonathan C.; And Others

1986-01-01

336

Endothelial function in male body builders taking anabolic androgenic steroids  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Adverse cardiovascular events have been reported in body builders taking anabolic steroids. Adverse effects of AAS on endothelial function can initiate atherosclerosis. This study evaluates endothelial function in body builders using AAS, compared with non-steroids using athletes as controls. Methods: We recruited 30 nonsmoking male body builders taking AAS, 14 in build up phase, 8 in work out phase, and 8 in post steroid phase, and 30 nonsmoking male athletes who denied ever using steroids. Serum lipids and fasting plasma glucose were measured to exclude dyslipidemia and diabetes. Brachial artery diameter was measured by ultrasound at rest, after cuff inflation, and after sublingual glyceriltrinitrate (GTN to determine flow mediated dilation (FMD, nitro mediated dilation (NMD and ratio of FMD to NMD (index of endothelial function. Result: Use of AAS was associated with higher body mass index (BMI and low density lipoprotein–cholesterol (LDL-C. Mean ratio of flow mediated dilatation after cuff deflation to post GTN dilatation of brachial artery (index of endothelial function in body builders taking AAS was significantly lower than control group (0.96(0.05 versus 1(0.08; p=0.03. After adjusting BMI, age and weight, no significant difference was seen in index of endothelial function between two groups (p=0 .21. Conclusion: Our study indicates that taking AAS in body builders doesn’t have direct effect on endothelial function. Future study with bigger sample size and measurement of AAS metabolites is recommended. Key words: endothelium, lipids, anabolic steroids, body builders

H Hashemi

2005-11-01

337

76 FR 72355 - Classification of Two Steroids, Prostanozol and Methasterone, as Schedule III Anabolic Steroids...  

Science.gov (United States)

...Pharmacologically Related to Testosterone A substance must also be pharmacologically related to testosterone (i.e., produce similar biological effects) to be classified as a Schedule III anabolic steroid. The pharmacology of a steroid, as related to...

2011-11-23

338

Neuroactive steroids and their role in epilepsy  

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Neuroactive steroids are the certain steroids that alter neuronal excitability via the cell surface through interaction with certain neurotransmitter receptors. Neuroactive steroids regulate physiological functions of the central nervous system and have possible therapeutic potential in neurological diseases. They have been shown to affect neuronal excitability via their interaction with the ligand-gated ion channel family, such as the GABAA receptor by acting genomically as well as nongenomi...

Patil, Chetan Y.; Jadhav, Shamsundar A.; Doifode, Sudhakar M.; Mirza Shiraz Baig

2012-01-01

339

Tendo Achillis pain: steroids and outcome.  

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A retrospective study is presented of 83 athletes with tendo Achillis pain (TAP) treated conservatively over a 12-year period from 1976 to 1988. Local steroid injections did not contribute to an earlier return to sport, though many individuals were improved symptomatically. Local steroids were not found to have a deleterious effect on outcome. Steroids were used most frequently in the chronic cases that presented late and had been treated previously: this group had most recurrences and surgic...

Read, M. T.; Motto, S. G.

1992-01-01

340

PLANT SCIENCES: Plant Genes on Steroids  

Science.gov (United States)

Access to the article is free, however registration and sign-in are required. Plants, like animals, use steroid hormones to regulate their development. However, in plants, the steroid hormone is bound by a receptor at the cell surface instead of a nuclear receptor. In a Perspective, Sablowski and Harberd discuss studies published here (He et al.) and elsewhere that provide the missing link between binding of the steroid by its receptor and changes in the expression of target genes.

Robert Sablowski (John Innes Centre;Department of Cell and Developmental Biology); Nicholas P. Harberd (John Innes Centre;Department of Cell and Developmental Biology)

2005-03-11

 
 
 
 
341

Levamisole treatment in steroid sensitive nephrotic syndrome.  

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OBJECTIVES To evaluate the effectiveness of levamisole in maintaining remission in children with steroid-sensitive nephrotic syndrome (SSNS) who had a frequent relapsing or steroid-dependent course. METHODS All children with SSNS who had a frequent relapsing or steroid-dependent course and were treated with levamisole between 1997 and 2001 at King Abdul-Aziz University Hospital, Jeddah, Kingdom of Saudi Arabia were reviewed. All patient...

Alshaya, Hammad O.; Kari, Jameela A.

2002-01-01

342

Steroid-induced ocular hypertension in Asian children with severe vernal keratoconjunctivitis  

Directory of Open Access Journals (Sweden)

Full Text Available Marcus Ang,1 Seng-Ei Ti,1 Raymond Loh,1 Sonal Farzavandi,1 Rongli Zhang,2 Donald Tan,1 Cordelia Chan11Singapore National Eye Centre, Singapore; 2Singapore Eye Research Institute, SingaporeBackground: We describe clinical characteristics and risk factors for corticosteroid response in children with severe vernal keratoconjunctivitis (VKC.Design: Retrospective, noncontrolled, comparative case series.Participants: Patients from three tertiary centers in Singapore.Methods: We reviewed patients with severe VKC (clinical grade > 2 who were on topical steroid therapy, with a minimum follow-up period of 1 year post-presentation. Logistic regression was used to determine risk factors for corticosteroid response.Main outcome measure: Corticosteroid response was defined as intraocular pressure (IOP>21 mmHg (three consecutive readings, or a rise of more than 16 mmHg from baseline, after commencement of steroid therapy in the absence of other possible causes of raised IOP.Results: Forty-one of 145 (28.3% patients developed a corticosteroid response, of which eight (5.5% progressed to glaucoma. The overall mean age of onset of VKC was 9.9 ± 4.4 years. Longer duration of corticosteroid use (OR, 5.06; 95% CI: 1.04–25.56; P = 0.45 and topical dexamethasone 0.01% (OR, 2.25; 95% CI: 1.99–5.08; P = 0.40 were associated with corticosteroid response. Mixed type of VKC (OR, 9.76; 95% CI: 3.55–26.77; P < 0.001, the presence of limbal neovascularization of ? three quadrants (OR, 6.33; 95% CI: 2.36–16.97; P < 0.001, and corneal involvement (OR, 3.51; 95% CI: 1.31–9.41; P = 0.012 were significant clinical risk factors after adjusting for potential confounders such as age, sex, ethnicity, duration, and type of corticosteroid used.Conclusion: Children on long-term oral corticosteroids with severe, mixed-type VKC and corneal involvement are more likely to develop corticosteroid response, and may require early treatment to prevent progression to glaucoma.Keywords: vernal keratoconjunctivitis, glaucoma, steroids

Ang M

2012-08-01

343

Body water, extracellular water, body potassium, and exchangeable sodium in body builders using anabolic steroids  

International Nuclear Information System (INIS)

Nine competitive male body builders aged 21 to 34 who were determined to take anabolic steroids were studied before and 6 to 10 weeks after a training cycle which included steroid administration. A control group of nine subjects matched in age and duration of competitive career, but using only natural training methods were studied on a single occasion while in training. Total body potassium (TBK) by 40K, total body water (TBW) by 3H2O dilution, extracellular water (ECW) by 35SO4 dilution and zero time extrapolation, and exchangeable sodium by 24Na dilution were measured before and after training. Intracellular water (ICW) was calculated from TBW - ECW. Initially steroid users had a greater skeletal muscle mass than control subjects, and obtained a further weight gain on steroids, all in skeletal muscle, based on parallel increases in TBK and ICW. Other body composition measurements did not change significantly. A single steroid user became ill taking steroids, decreased potassium by 5%, and increased extracellular water, changes which may represent the effects of hepatic dysfunction which occurred while on anabolic steroids

344

Steroid profiling in doping analysis  

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Profiling androgens in urine samples is used in doping analysis for the detection of abused steroids of endogenous origin. These profiling techniques were originally developed for the analysis of testosterone, mostly by means of the ratio of testosterone to epitestosterone (T/E ratio). A study was performed on the influence of alcohol consumption on the T/E ratio. The applied dose increased the ratio of both males and females and it showed that, under the studied conditions, the risk of a pos...

Kerkhof, Danie?l Henri

2001-01-01

345

Topical steroid induced chronic demodicidosis.  

Science.gov (United States)

We report a 39-year-old female patient who developed pruritic erythematous telangiectatic patches with scaly follicular papules on the neck and upper chest for 4 years. Ten per cent potassium hydroxide preparation of skin scrapings revealed Demodex folliculorum. Histology showed three Demodex mites in one of the hair follicles. She was treated with a topical steroid without improvement. The skin lesions and Demodex mite disappeared after a single application of 1 per cent gamma benzene hexachloride but twice daily application of 1 per cent gamma benzene hexachloride for 2 weeks was needed to prevent recurrence. PMID:1711556

Sakuntabhai, A; Timpatanapong, P

1991-02-01

346

Steroidal glycosides from Hoodia gordonii.  

Science.gov (United States)

Ten new C21-steroidal derivatives, namely gordonosides A-L (1-10) were isolated from a chloroform extract of the aerial parts of Hoodia gordonii, a plant widely used in the nutraceutical market as an ingredient of weight loss supplements. Compounds (2-10) are based on 3beta,14beta-dihydroxy-pregn-5-en-17-betaone aglycone (1). Their structures were characterized on the basis of HR-MS spectrometry and both 1D and 2D NMR techniques. PMID:17485103

Dall'Acqua, Stefano; Innocenti, Gabbriella

2007-06-01

347

Determinación del genero por medio de medidas y verificación del peso del hueso esternon (Brasil Sex determination by measures and weight verification of sternum bone.Brasil  

Directory of Open Access Journals (Sweden)

Full Text Available La determinación del género humano (sexo es una de las principales atribuciones del odontólogo forense y del médico legista encargados del análisis antropológico de esqueletos, piezas y fragmentos óseos. Entre los huesos que pueden y deben ser analizados se encuentra el hueso esternón, considerando, principalmente, sus características particulares. En el presente estudio fueron medidos y pesados 100 huesos esternón, siendo 50 del género femenino y 50 del género masculino, provenientes de Cuiabá, Mato Grosso, Brasil, con edades comprendidas entre 19 y 103 años. Fue verificado que la medida del centro de la escotadura de inserción del primer arco costal derecho al izquierdo y el peso del manubrio y cuerpo del esternón, altamente significantes, constituyen parámetros para determinar el género. Fue obtenida, también, una fórmula matemática que posibilita determinar el género en análisis futuras con índices de acierto de 69,2%. (SEX DETERMINATION BY MEASURES AND WEIGHT VERIFICATION OF ESTERNUM BONEHuman gender determination is one of the main attributions of forensic odontologists and forensic pathologists responsible for the anthropological analysis of skeletons, parts and fragmented bones. One of the bones that can and must be analyzed is the sternum, considering its particular characteristics. In the present study we’ve measured and weighed 100 sternums, 50 belonging to female gender and 50 to male gender proceeding from Cuiabá-MT, with age varying between 19 and 103 years. It was verified that the measure of the center of the chamfer of the insertion of the first to the left costal arc and the weight of the manubrium and body of sternum, are highly significant, becoming parameters to determine the gender. A mathematical formula was also obtained that permitted to determine the gender in future analyses with indices of 69,2%. (SEX DETERMINATION BY MEASURES AND WEIGHT VERIFICATION OF ESTERNUM BONE

Antonio Queiroz

2005-03-01

348

Determinación del genero por medio de medidas y verificación del peso del hueso esternon (Brasil) / Sex determination by measures and weight verification of sternum bone.Brasil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish La determinación del género humano (sexo) es una de las principales atribuciones del odontólogo forense y del médico legista encargados del análisis antropológico de esqueletos, piezas y fragmentos óseos. Entre los huesos que pueden y deben ser analizados se encuentra el hueso esternón, considerando [...] , principalmente, sus características particulares. En el presente estudio fueron medidos y pesados 100 huesos esternón, siendo 50 del género femenino y 50 del género masculino, provenientes de Cuiabá, Mato Grosso, Brasil, con edades comprendidas entre 19 y 103 años. Fue verificado que la medida del centro de la escotadura de inserción del primer arco costal derecho al izquierdo y el peso del manubrio y cuerpo del esternón, altamente significantes, constituyen parámetros para determinar el género. Fue obtenida, también, una fórmula matemática que posibilita determinar el género en análisis futuras con índices de acierto de 69,2%. (SEX DETERMINATION BY MEASURES AND WEIGHT VERIFICATION OF ESTERNUM BONE) Abstract in english Human gender determination is one of the main attributions of forensic odontologists and forensic pathologists responsible for the anthropological analysis of skeletons, parts and fragmented bones. One of the bones that can and must be analyzed is the sternum, considering its particular characterist [...] ics. In the present study we’ve measured and weighed 100 sternums, 50 belonging to female gender and 50 to male gender proceeding from Cuiabá-MT, with age varying between 19 and 103 years. It was verified that the measure of the center of the chamfer of the insertion of the first to the left costal arc and the weight of the manubrium and body of sternum, are highly significant, becoming parameters to determine the gender. A mathematical formula was also obtained that permitted to determine the gender in future analyses with indices of 69,2%. (SEX DETERMINATION BY MEASURES AND WEIGHT VERIFICATION OF ESTERNUM BONE)

Antonio, Queiroz; Ronaldo B, Wada; Antonio, Preza; Célio, Spadacio; Belkys, De la Cruz.

2005-03-01

349

21 CFR 1308.34 - Exempt anabolic steroid products.  

Science.gov (United States)

...2010-04-01 false Exempt anabolic steroid products. 1308.34 Section 1308.34 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION...CONTROLLED SUBSTANCES Exempt Anabolic Steroid Products § 1308.34 Exempt anabolic steroid...

2010-04-01

350

21 CFR 1308.34 - Exempt anabolic steroid products.  

Science.gov (United States)

... 2010-04-01 false Exempt anabolic steroid products. 1308.34 Section 1308.34...OF CONTROLLED SUBSTANCES Exempt Anabolic Steroid Products § 1308.34 Exempt anabolic steroid products. The list of compounds,...

2010-04-01

351

Stress and Sex Versus Immunity and Inflammation  

Science.gov (United States)

Glucocorticoids, the major effector hormones of the stress system, influence almost all aspects of mammalian physiology. These steroids exert their effects on a large network of primary, secondary, and tertiary target genes, encompassing up to 20% of the expressed genome in a tissue. New evidence shows quantitative and qualitative gender-specific differences in the actions of glucocorticoids on the rat liver transcriptome, suggesting that the pervasive actions of these hormones are modulated by gender, both as an inherent property of the target tissues and as a result of exposure of these tissues to estrogens and possibly also androgens. Generally, albeit not always, female mammals have more robust behavioral and somatic responses to stress and more potent immune and inflammatory reactions than males—differences that are inherent, sex steroid–mediated, or both and possibly the evolutionary products of natural selection of female and male roles.

George P. Chrousos (University of Athens; Children's Hospital Aghia Sophia REV)

2010-10-12

352

Identification of sex hormone-binding globulin in the human hypothalamus  

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Gonadal steroids are known to influence hypothalamic functions through both genomic and non-genomic pathways. Sex hormone-binding globulin ( SHBG) may act by a non-genomic mechanism independent of classical steroid receptors. Here we describe the immunocytochemical mapping of SHBG-containing neurons and nerve fibers in the human hypothalamus and infundibulum. Mass spectrometry and Western blot analysis were also used to characterize the biochemical characteristics of SHBG in the hypothalamus ...

Herbert, Zso?fia; Go?the, Susanne; Caldwell, Jack D.; Bernstein, Hans-gert; Melle, Christian; Eggeling, Ferdinand Von; Lewis, John; Jirikowski, Gustav F.

2005-01-01

353

Sex Hormone-Binding Globulin Genetic Variation: Associations with Type 2 Diabetes Mellitus and Polycystic Ovary Syndrome  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sex hormone-binding globulin (SHBG) is the primary plasma transport protein for sex steroid hormones and regulates the bioavailability of these hormones to target tissues. The gene encoding SHBG is complex and any of several polymorphisms in SHBG have been associated with alterations in circulating SHBG levels.

Chen, Chen; Smothers, Jamie C.; Lange, Allison; Nestler, John E.; Strauss, Jerome F.; Wickham, Edmond P.

2010-01-01

354

Osteonecrosis following alcohol, cocaine, and steroid use.  

LENUS (Irish Health Repository)

Alcohol, steroids and cocaine have all been shown to be independent risk factors for osteonecrosis when taken in excess. Here we present a case of a young girl who developed debilitating osteonecrosis secondary to low doses of alcohol, steroids and cocaine. We feel it is important to highlight to those caring for such patients of the potential devastating complication of these three agents.

Ziraldo, Laura

2012-02-01

355

Steroids: To Test or to Educate?  

Science.gov (United States)

In February 2005, The Dallas Morning News published a multipart series on steroid use among high school students in Texas. The paper's four-month investigation was wide-ranging, but shined a particular spotlight upon alleged abuses in the 13,700-student Grapevine-Colleyville Independent School District, north of Dallas. Use of steroids and other…

LaFee, Scott

2006-01-01

356

Steroids Update, Part 1 and Part 2.  

Science.gov (United States)

Part 1 of this two-part article describes the views of a physician who believes that athletes who want to take steroids are best protected by receiving a prescription and monitoring. Part 2 discusses the more general view of physicians that steroids should not be prescribed but perhaps should be monitored. (MT)

Miller, Calvin; Duda, Marty

1986-01-01

357

Scientists Report Advance in Understanding Steroid Receptors  

Science.gov (United States)

Scientists have long known that proteins called steroid receptors play a critical role in switching on hormone-responsive genes. What has been unclear is how these proteins orchestrate the process, a key issue in learning to control genes activated by steroid hormones such as androgen and estrogen.

358

Public health measures to control the spread of antimicrobial resistance in Neisseria gonorrhoeae in men who have sex with men.  

Science.gov (United States)

SUMMARY Gonorrhoea is one of the most common sexually transmitted infections. The control of gonorrhoea is extremely challenging because of the repeated development of resistance to the antibiotics used for its treatment. We explored different strategies to control the spread of antimicrobial resistance and prevent increases in gonorrhoea prevalence. We used a mathematical model that describes gonorrhoea transmission among men who have sex with men and distinguishes gonorrhoea strains sensitive or resistant to three antibiotics. We investigated the impact of combination therapy, switching first-line antibiotics according to resistance thresholds, and other control efforts (reduced sexual risk behaviour, increased treatment rate). Combination therapy can delay the spread of resistance better than using the 5% resistance threshold. Increased treatment rates, expected to enhance gonorrhoea control, may reduce gonorrhoea prevalence only in the short term, but could lead to more resistance and higher prevalence in the long term. Re-treatment of resistant cases with alternative antibiotics can substantially delay the spread of resistance. In conclusion, combination therapy and re-treatment of resistant cases with alternative antibiotics could be the most effective strategies to prevent increases in gonorrhoea prevalence due to antimicrobial resistance. PMID:25275435

Xiridou, M; Soetens, L C; Koedijk, F D H; VAN DER Sande, M A B; Wallinga, J

2014-10-01

359

Generation of Breast Cancer Stem Cells by Steroid Hormones in Irradiated Human Mammary Cell Lines  

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Exposure to ionizing radiation was shown to result in an increased risk of breast cancer. There is strong evidence that steroid hormones influence radiosensitivity and breast cancer risk. Tumors may be initiated by a small subpopulation of cancer stem cells (CSCs). In order to assess whether the modulation of radiation-induced breast cancer risk by steroid hormones could involve CSCs, we measured by flow cytometry the proportion of CSCs in irradiated breast cancer cell lines after progesteron...

Vares, Guillaume; Cui, Xing; Wang, Bing; Nakajima, Tetsuo; Nenoi, Mitsuru

2013-01-01

360

Differential effects of angiostatic steroids and dexamethasone on angiogenesis and cytokine levels in rat sponge implants.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

1. Subcutaneous implantation of sterile polyether sponges elicited a reproducible neovascular response in rats, as determined by blood flow measurement with a 133Xe clearance technique and confirmed histologically. This model was used to monitor the levels of two cytokines during angiogenesis and to compare the activities of angiostatic steroids and anti-inflammatory steroids. 2. Initial experiments followed the neovascular development over a 20-day period. Daily local injection of hydrocorti...

Hori, Y.; Hu, D. E.; Yasui, K.; Smither, R. L.; Gresham, G. A.; Fan, T. P.

1996-01-01

 
 
 
 
361

Steroid-Refractory Acute GVHD: Predictors and Outcomes  

Science.gov (United States)

Patients with steroid-resistant acute graft versus host disease (aGVHD) have a dismal prognosis, with mortality rates in excess of 90%. We sought to identify a subgroup of patients less likely to benefit from initial therapy with corticosteroids as well as the impact of response on day 14 on outcome. Retrospective evaluation was performed of patients with biopsy-proven aGVHD treated with corticosteroids after allogeneic HSCT at M.D. Anderson Cancer Center from 1998 through 2002 (N = 287). Overall response to first-line therapy on day 14 was 56%. Grade III-IV aGVHD and hyperacute GVHD were the most significant factors predicting failure. Patients who fail to respond to steroids by day 14 should be considered for clinical trials. Severity of aGVHD, hyperacute GVHD, and sex mismatch could be integrated into prognostic scoring systems which may allow for pretreatment identification of patients unlikely to benefit from standard therapy with corticosteroids. PMID:22110505

Westin, Jason R.; Saliba, Rima M.; De Lima, Marcos; Alousi, Amin; Hosing, Chitra; Qazilbash, Muzaffar H.; Khouri, Issa F.; Shpall, Elizabeth J.; Anderlini, Paolo; Rondon, Gabriela; Andersson, Borje S.; Champlin, Richard; Couriel, Daniel R.

2011-01-01

362

Steroid-Refractory Acute GVHD: Predictors and Outcomes.  

Science.gov (United States)

Patients with steroid-resistant acute graft versus host disease (aGVHD) have a dismal prognosis, with mortality rates in excess of 90%. We sought to identify a subgroup of patients less likely to benefit from initial therapy with corticosteroids as well as the impact of response on day 14 on outcome. Retrospective evaluation was performed of patients with biopsy-proven aGVHD treated with corticosteroids after allogeneic HSCT at M.D. Anderson Cancer Center from 1998 through 2002 (N = 287). Overall response to first-line therapy on day 14 was 56%. Grade III-IV aGVHD and hyperacute GVHD were the most significant factors predicting failure. Patients who fail to respond to steroids by day 14 should be considered for clinical trials. Severity of aGVHD, hyperacute GVHD, and sex mismatch could be integrated into prognostic scoring systems which may allow for pretreatment identification of patients unlikely to benefit from standard therapy with corticosteroids. PMID:22110505

Westin, Jason R; Saliba, Rima M; De Lima, Marcos; Alousi, Amin; Hosing, Chitra; Qazilbash, Muzaffar H; Khouri, Issa F; Shpall, Elizabeth J; Anderlini, Paolo; Rondon, Gabriela; Andersson, Borje S; Champlin, Richard; Couriel, Daniel R

2011-01-01

363

Photoelectron spectroscopy of non-steroidal anti-inflammatory drugs  

Science.gov (United States)

The electronic structures of eight non-steroidal anti-inflammatory drugs (NSAIDs) had been studied by UV photoelectron spectroscopy (UPS) and high-level Green's function (GF) calculations. Our UPS data show that the electronic structure influences the measured biological activity of NSAID, but that it is not the dominating factor. The role of electronic structure needs to be considered in conjunction with other factors like steric properties of the COX active site and orientation of relevant residues in the same site.

Novak, Igor; Klasinc, Leo; Chong, Delano P.; McGlynn, Sean P.

2013-08-01

364

ABUSE OF ANABOLIC ANDROGENIC STEROIDS  

Directory of Open Access Journals (Sweden)

Full Text Available According to the International Olympic Committee, the abuse of anabolic androgenic steroids (AASS is found in over 50% of positive doping tests. AASS abuse is not restricted to the organized sports andwidespread use. It remains as an unsolved public-health problem.Lower black market price, easier access to AASS, bodybuilding clubs and internet advertising are factors of this increasingly misuse. There is not real data about the prevalence of AASS abuse in various populations or countries, because most of athletes or students, due to their prohibition or ethical aspects do not admit to AASS abuse. Often they are aware of the risks of their choice and yet, are eager to put themselves at risk without deeper consideration. The abusers use them to improve their physical fitness and appearance.Present article has been collected to elucidate the risks and adverse effects of AASS and explanation of mechanisms of these events.

Abbas Yavari

2009-09-01

365

Anabolic-androgenic steroids. Current issues.  

Science.gov (United States)

The use of drugs to enhance physical performance has been observed for thousands of years. Today, individuals continue to use a variety of substances, including anabolic-androgenic steroids, in the hope of enhancing their performance and appearance. Rumours persist regarding the incidence of the nonmedical use of anabolic steroids by athletes and nonathletes: however, true estimates are now available based on the results of systematic surveys. Although the vast majority of the athletic community accepts that anabolic steroids enhance performance and appearance, the extent to which this occurs and the factors influencing such effects remain incompletely understood and documented. Refinement of our knowledge of the ergogenic effects of anabolic steroids is not without merit; however, the existing scientific evidence coupled with an overwhelming number of anecdotal accounts argues against devoting significant resources to this area of investigation at present. The short term health effects of anabolic steroids have been increasingly studied and reviewed, and while anabolic steroid use has been associated with several adverse and even fatal effects, the incidence of serious effects thus far reported has been extremely low. The long term effects of anabolic steroid use are generally unknown. Unfortunately, the lack of scientific information on long term health effects has impeded, if not precluded, the formation of effective health education and drug abuse prevention strategies. Consequently, efforts should be expanded in the areas of prevention and education. PMID:7618010

Yesalis, C E; Bahrke, M S

1995-05-01

366

Age- and sex-related bone uptake of Tc-99m-HDP measured by whole-body bone scanning  

International Nuclear Information System (INIS)

Aim of this study was to validate a recently introduced new and easy-to-perform method for quantifying bone uptake of Tc-99m-labelled diphosphonate in a routine clinical setting and to establish a normal data base for bone uptake depending on age and gender. Methods: In 49 women (14-79 years) and 47 men (6-89 years) with normal bone scans as well as in 49 women (33-81 years) and 37 men (27-88 years) with metastatic bone disease whole-body bone scans were acquired at 3 min and 3-4 hours p.i. to calculate bone uptake after correction for both urinary excretion and soft tissue retention. Results: Bone uptake values of various age-related subgroups showed no significant differences between men and women (p>0.05). Furthermore, no differences could be proven between age-matched subgroups of normals and patients with less than 10 metastatic bone lesions, while patients with wide-spread bone metastases revealed significantly increased uptake values. In both men and women highest bone uptake was obtained (p<0.05) in subjects younger than 20 years with active epiphyseal growth plates. In men, bone uptake slowly decreased with age up to 60 years and then showed a tendency towards increasing uptake values. In women, the mean uptake reached a minimum in the decade 20-29 years and then slowly increased with a positive linear correlation of age and uptake in subjects older than 55 years (r=0.57). Conclusion: Since the results proposed in this study are in good agreement with data frs study are in good agreement with data from literature, the new method used for quantification could be validated in a large number of patients. Furthermore, age- and sex-related normal bone uptake values of Tc-99m-HDP covering a wide range of age could be presented for this method as a basis for further studies on bone uptake. (orig.)

367

Sex and Arthritis  

Science.gov (United States)

... Pain Pregnancy and Rheumatic Disease Sex and Arthritis Sex and Arthritis PRINT Download PDF Description Sexuality is ... sensation Erectile dysfunction or impotence Begin overcoming barriers Sex is not simply about reaching rapid orgasm with ...

368

Sex-linked dominant  

Science.gov (United States)

Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... type of chromosome that is affected (autosomal or sex chromosome). It also depends on whether the trait ...

369

Zebrafish sex determination and differentiation: Involvement of FTZ-F1 genes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Sex determination is the process deciding the sex of a developing embryo. This is usually determined genetically; however it is a delicate process, which in many cases can be influenced by environmental factors. The mechanisms controlling zebrafish sex determination and differentiation are not known. To date no sex linked genes have been identified in zebrafish and no sex chromosomes have been identified. However, a number of genes, as presented here, have been linked to the process of sex determination or differentiation in zebrafish. The zebrafish FTZ-F1 genes are of central interest as they are involved in regulating interrenal development and thereby steroid biosynthesis, as well as that they show expression patterns congruent with reproductive tissue differentiation and function. Zebrafish can be sex reversed by exposure to estrogens, suggesting that the estrogen levels are crucial during sex differentiation. The Cyp19 gene product aromatase converts testosterone into 17 beta-estradiol, and when inhibited leads to male to female sex reversal. FTZ-F1 genes are strongly linked to steroid biosynthesis and the regulatory region of Cyp19 contains binding sites for FTZ-F1 genes, further linking FTZ-F1 to this process. The role of FTZ-F1 and other candidates for zebrafish sex determination and differentiation is in focus of this review.

Olsson Per-Erik

2005-11-01

370

Epidural steroid injections in the treatment of symptomatic lumbar spinal stenosis associated with epidural lipomatosis.  

Science.gov (United States)

Epidural lipomatosis has been implicated as a cause or contributor of symptomatic lumbar spinal stenosis. Although epidural steroid injections have been very successful for symptomatic treatment of spinal stenosis; their role in treatment of symptomatic stenosis secondary to epidural lipomatosis is unclear. A review literature (MEDLINE, PubMed) found no reports justifying the use of steroids. We present two patients with lumbar epidural lipomatosis causing or contributing to symptomatic spinal stenosis. Both patients presented with unilateral lower limb radicular symptoms unrelieved with conservative measures such as medications and physical therapy. They were treated with a single transforaminal epidural steroid injection at the symptomatic level. Both had 80-85% pain relief. These reports suggest a beneficial role of epidural steroid injections for patients with symptomatic lumbar spinal stenosis caused by or contributing to epidural lipomatosis. PMID:15624572

Botwin, Kenneth P; Sakalkale, Durgadas P

2004-12-01

371

Steroid plant hormones: Effects outside plant kingdom.  

Science.gov (United States)

Brassinosteroids (BS) are the first group of steroid-hormonal compounds isolated from and acting in plants. Among numerous physiological effects of BS growth stimulation and adaptogenic activities are especially remarkable. In this review, we provide evidence that BS possess similar types of activity also beyond plant kingdom at concentrations comparable with those for plants. This finding allows looking at steroids from a new point of view: how common are the mechanisms of steroid bioregulation in different types of organisms from protozoa to higher animals. PMID:25217849

Zhabinskii, Vladimir N; Khripach, Natalia B; Khripach, Vladimir A

2014-09-01

372

Homologous Series of Liquid Crystalline Steroidal Lipids  

Energy Technology Data Exchange (ETDEWEB)

Steroids are an important source of chiral mesophases. The melting behavior and mesomorphic properties of homologous series of steroidal derivatives have been extracted from the literature, tabulated, and discussed. The tables provide the reader with an evaluated compilation of the type of mesophases found for the individual compounds, including their transition temperatures. Where the literature gives more than one set of data for a specific substance, one has been chosen as the main reference, but all alternatives are listed in the footnotes. The data can be used for statistical analysis to show the specific role of substructures within the steroidal framework. {copyright} {ital 1997} {ital American Institute of Physics and American Chemical Society}

Thiemann, T.; Vill, V. [Institut fuer Organische Chemie, Martin-Luther-King Platz 6, D-20146 Hamburg (Germany)

1997-03-01

373

Genomics of Sex and Sex Chromosomes  

Science.gov (United States)

Sex chromosomes are distinctive, not only because of their gender determining role, but also for genomic features that reflect their evolutionary history. The genomic sequences in the ancient sex chromosomes of humans and in the incipient sex chromosomes of medaka, stickleback, and papaya exhibit u...

374

Odontometric sex assessment in Indians.  

Science.gov (United States)

Sex determination of unidentified skeletal remains is important and various hard-tissue parameters have been evaluated towards this end. The dentition is considered as a useful adjunct in skeletal sex determination, particularly since teeth are resistant to postmortem destruction and fragmentation. Sex dimorphism in tooth size and the accuracy of odontometric sex prediction, is found to vary in different regions and researchers have advocated the need for population-specific data. No odontometric standards exist for Indians for use in forensic sex prediction. Therefore, this study examined sexual dimorphism in Indians using univariate and multivariate statistics. Mesiodistal (MD) and buccolingual (BL) measurements of all teeth, except third molars, were obtained on dental casts of [corrected] 105 Indians (52 females, 53 males). The canines were [corrected] found to be the most dimorphic tooth, followed by the [corrected] BL dimensions of [corrected]first molars and that of mandibular second premolars. In general, mandibular teeth and BL dimensions showed greater tendency to be larger in males. However, just over a quarter of the measured variables (16/56; 28.6%) were statistically larger in males (p stepwise discriminant analysis were either statistically larger in males or exhibited reverse dimorphism, indicating that such tooth variables may have better ability to correctly identify sex. [corrected] PMID:19744808

Prabhu, Sudeendra; Acharya, Ashith B

2009-11-20

375

Pediatric idiopathic nephrotic syndrome: treatment strategies in steroid dependent and steroid resistant forms.  

Science.gov (United States)

Idiopathic nephrotic syndrome (INS) is defined as massive proteinuria and hypoalbuminemia associated with dyslipidemia and generalized oedema in most cases. It is thought to be due to a plasma factor of immunologic origin. Most cases are steroid responsive. However, a considerable proportion of children run a steroid dependent course. Calcineurin inhibitors and alkylating agents have been classical treatment strategies for such cases, but specific toxicity limits the use of these drugs. Mycophenolate mofetil (MMF) is an inhibitor of inosine monophosphate dehydrogenase and thus de novo purine synthesis. Several uncontrolled clinical trials have demonstrated the efficacy of MMF in steroid dependent NS with or without prior use of CyP and in children with nephrotoxicity due to prolonged CyA treatment. Non-compliance to steroid therapy can be responsible for multiple relapses and may be misinterpreted as steroid dependency and may therefore lead to unjustified increase of immunosuppressive treatment. Triamcinolone acetonide, a long acting steroid for intramuscular injection, can replace the usual oral prednisone treatment if non-compliance is suspected. Whereas the treatment of the primary course of INS is well established, steroid dependent and steroid resistant forms are still a challenge for pediatric nephrologists. Both under-treatment with multiple relapses with disease or steroid associated morbidity on the one hand and over-treatment with specific side effects of immunosuppressive drugs may have severe consequences for the patients. PMID:20156172

Ulinski, T; Aoun, B

2010-01-01

376

Antifungal Activity of C-27 Steroidal Saponins  

Science.gov (United States)

As part of our search for new antifungal agents from natural resources, 22 C-27 steroidal saponins and 6 steroidal sapogenins isolated from several monocotyledonous plants were tested for their antifungal activity against the opportunistic pathogens Candida albicans, Candida glabrata, Candida krusei, Cryptococcus neoformans, and Aspergillus fumigatus. The results showed that the antifungal activity of the steroidal saponins was associated with their aglycone moieties and the number and structure of monosaccharide units in their sugar chains. Within the 10 active saponins, four tigogenin saponins (compounds 1 to 4) with a sugar moiety of four or five monosaccharide units exhibited significant activity against C. neoformans and A. fumigatus, comparable to the positive control amphotericin B. The antifungal potency of these compounds was not associated with cytotoxicity to mammalian cells. This suggests that the C-27 steroidal saponins may be considered potential antifungal leads for further preclinical study. PMID:16641439

Yang, Chong-Ren; Zhang, Ying; Jacob, Melissa R.; Khan, Shabana I.; Zhang, Ying-Jun; Li, Xing-Cong

2006-01-01

377

[Steroid use in free time bodybuilders].  

Science.gov (United States)

A sample of 74 male bodybuilders was analyzed for relationships between steroid abuse (abuse n=31; no abuse n=43) and self-esteem (Multidimensionale Selbstwertskala MSWS), body-image (Body-Image Questionnaire FK-ASA) as well as teasing (Physical Appearance Related Teasing Scale PARTS). In a logistic regression analysis age (p=0.001), low values for body expression (p=0.036) and high self-esteem (p=0.024) predicted steroid intake; training frequency or teasing experiences showed no effect. Contrary to earlier findings high and not low self-esteem was associated with steroid abuse. Because of the overlap between constructs narcissism and self-esteem further studies should disentangle the role of narcissism and self-esteem for steroid abuse in bodybuilders. PMID:22161857

Michels-Lucht, Felicitas; Schirmer, Jan; Klauer, Thomas; Freyberger, Harald; Lucht, Michael

2011-12-01

378

Steroidal glycosides from Cynanchum forrestii Schlechter.  

Science.gov (United States)

Nine new steroidal glycosides, cynaforrosides B, C, D, E, and F, based on a 13, 14: 14, 15-disecopregnane-type skeleton, cynaforrosides G, H, and I with a new aglycone named cynaforrogenin A, and cynaforroside J together with three known C21 steroidal glycosides cynatratoside A, hancoside and komaroside C were isolated from the ethanol extract of the roots of Cynanchum forrestii Schlechter. The structures of new compounds were determined on the basis of spectral and chemical evidence. Steroidal glycosides with three kinds of skeletons were isolated from this plant simultaneously. The sugar units of cynaforrosides B-I contained two moieties of glucoses and especially cynaforrosides E-I contained two glucoses with the mode of 1-->6 linkage, which were rare among steroidal glycosides of the genus Cynanchum. PMID:16256157

Liu, Yue; Hu, Youcai; Yu, Shishan; Fu, Guangmiao; Huang, Xiangzhong; Fan, Lihua

2006-01-01

379

Differences between seven measures of self-reported numbers of clients of female sex workers in southern India: implications for individual- and population-level analysis.  

Science.gov (United States)

Quantifying sexual activity of sub-populations with high-risk sexual behaviour is important in understanding HIV epidemiology. This study examined inconsistency of seven outcomes measuring self-reported clients per month (CPM) of female sex workers (FSWs) in southern India and implications for individual/population-level analysis. Multivariate negative binomial regression was used to compare key social/environmental factors associated with each outcome. A transmission dynamics model was used to assess the impact of differences between outcomes on population-level FSW/client HIV prevalence. Outcomes based on 'clients per last working day' produced lower estimates than those based on 'clients per typical day'. Although the outcomes were strongly correlated, their averages differed by approximately two-fold (range 39.0-79.1 CPM). The CPM measure chosen did not greatly influence standard epidemiological 'risk factor' analysis. Differences across outcomes influenced HIV prevalence predictions. Due to this uncertainty, we recommend basing population-based estimates on the range of outcomes, particularly when assessing the impact of interventions. PMID:22886176

Deering, Kathleen N; Vickerman, P; Pickles, M; Moses, S; Blanchard, J F; Ramesh, B M; Isac, S; Boily, M-C

2013-02-01

380

Steroids from the gorgonian Isis hippuris.  

Science.gov (United States)

Six new polyoxygenated steroids, hippuristerones J-L (1-3), hippuristerols E-F (4, 5), and a novel gorgosteroid, 1alpha,3beta,5beta,11alpha-tetrahydroxygorgostan-6-one (6), were isolated from the gorgonian Isis hippuris. The structures of these metabolites were elucidated by extensive spectroscopic analyses and comparison of the NMR data with those of related steroids. PMID:16180815

Chao, Chih-Hua; Huang, Long-Fei; Wu, Shwu-Li; Su, Jui-Hsin; Huang, Ho-Cheng; Sheu, Jyh-Horng

2005-09-01

 
 
 
 
381

Polyhydroxylated steroidal glycosides from Paris polyphylla.  

Science.gov (United States)

Three new steroidal saponins, parisyunnanosides G-I (1-3), one new C(21) steroidal glycoside, parisyunnanoside J (4), and three known compounds, padelaoside B (5), pinnatasterone (6), and 20-hydroxyecdyson (7), were isolated from the rhizomes of Paris polyphylla Smith var. yunnanensis. Compounds 1 and 3 have unique trisdesmoside structures that include a C-21 ?-d-galactopyranose moiety. All compounds were evaluated for their cytotoxicity against human CCRF leukemia cells. PMID:22663190

Kang, Li-Ping; Liu, Yi-Xun; Eichhorn, Tolga; Dapat, Else; Yu, He-shui; Zhao, Yang; Xiong, Cheng-Qi; Liu, Chao; Efferth, Thomas; Ma, Bai-Ping

2012-06-22

382

Cigarette smoking and steroid hormones in women.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Epidemiological evidence has suggested that cigarette smoking has an anti-oestrogenic effect in women, but the effects of smoking on steroid hormone metabolism are not fully understood. We compared serum concentrations of oestradiol, progesterone (luteal phase) and dehydroepiandrosterone sulphate (DHEA-S), and urinary excretion rates of six steroids of predominantly adrenal origin, in healthy premenopausal and postmenopausal female smokers and non-smokers. Serum concentrations of oestradiol, ...

Key, Tj; Pike, Mc; Baron, Ja; Moore, Jw; Wang, Dy; Thomas, Bs; Bulbrook, Rd

1991-01-01

383

New steroid derivative with hypoglycemic activity  

Science.gov (United States)

Data indicates that some steroid derivatives may induce changes on glucose levels; nevertheless, data are very confusing. Therefore, more pharmacological data are needed to characterize the activity induced by the steroid derivatives on glucose levels. The aim of this study was to synthesize a new steroid derivative for evaluate its hypoglycemic activity. The effects of steroid derivative on glucose concentration were evaluated in a diabetic animal model using glibenclamide and metformin as controls. In addition, the pregnenolone-dihydrotestosterone conjugate was bound to Tc-99m using radioimmunoassay methods, to evaluate the pharmacokinetics of the steroid derivative over time. The results showed that the pregnenolone-dihydrotestosterone conjugate induces changes on the glucose levels in similar form than glibenclamide. Other data showed that the biodistribution of Tc-99m-steroid derivativein brain was higher in comparison with spleen, stomach, intestine liver and kidney. In conclusion, the pregnenolone-dihydrotestosterone conjugate exerts hypoglycemic activity and this phenomenon could depend of its physicochemical properties which could be related to the degree of lipophilicity of the steroidderivative. PMID:25550906

Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Lenin, Hau-Heredia; Elodia, García-Cervera; Eduardo, Pool-Gómez; Marcela, Rosas-Nexticapa; Bety, Sarabia-Alcocer

2014-01-01

384

Antenatal steroids: can we optimize the dose?  

Science.gov (United States)

Purpose of review The beneficial effects of antenatal steroids in women at risk of preterm birth are evident. A dose of 24?mg appears sufficient, but there are insufficient data to recommend betamethasone or dexamethasone, a single steroid dose, the optimal interval between doses and repeated courses, the gestational age at which treatment is beneficial and the long-term effects of steroid treatment. This review addresses these aspects of antenatal steroid treatment. Recent findings Although the 12-h and 24-h dosing intervals are equivalent with respect to prevention of respiratory distress syndrome, the former enables the completion of treatment in 50% more neonates delivered prematurely. Reducing the single steroid dose in patients at risk for premature birth reduces the associated maternal side effects. An inverse relationship has been demonstrated between the number of corticosteroid courses and foetal growth. The reduced size of exposed foetuses has been attributed to birth at earlier gestational ages and decreased foetal growth. Evidence suggests that antenatal exposure to synthetic glucocorticoids in term-born children has long-lasting effects, which may have important implications in the recommendation of steroids before elective caesarean at term. Summary The short-term and long-term effects of the dosage regimen on the pregnant mother and foetus remain unclear. PMID:24463225

Romejko-Wolniewicz, Ewa; Teliga-Czajkowska, Justyna; Czajkowski, Krzysztof

2014-01-01

385

Mitochondrial benzodiazepine receptors regulate steroid biosynthesis  

Energy Technology Data Exchange (ETDEWEB)

Recent observations on the steroid synthetic capability within the brain open the possibility that benzodiazepines may influence steroid synthesis in nervous tissue through interactions with peripheral-type benzodiazepine recognition sites, which are highly expressed in steroidogenic cells and associated with the outer mitochondrial membrane. To examine this possibility nine molecules that exhibit a greater than 10,000-fold difference in their affinities for peripheral-type benzodiazepine binding sites were tested for their effects on a well-established steroidogenic model system, the Y-1 mouse adrenal tumor cell line. 4{prime}-Chlorodiazepam, PK 11195, and PK 14067 stimulated steroid production by 2-fold in Y-1 cells, whereas diazepam, flunitrazepam, zolpidem, and PK 14068 displayed a lower (1.2- to 1.5-fold) maximal stimulation. In contrast, clonazepam and flumazenil did not stimulate steroid synthesis. The potencies of these compounds to inhibit {sup 3}H-labeled PK 11195 binding to peripheral-type benzodiazepine recognition sites correlated with their potencies to stimulate steroid production. Similar findings were observed in bovine and rat adrenocortical cell preparations. These results suggest that ligands of the peripheral-type benzodiazepine recognition site acting on this mitochondrial receptor can enhance steroid production. This action may contribute specificity to the pharmacological profile of drugs preferentially acting on the benzodiazepine recognition site associated with the outer membrane of certain mitochondrial populations.

Mukhin, A.G.; Papadopoulos, V.; Costa, E.; Krueger, K.E. (Georgetown Univ. School of Medicine, Washington, DC (USA))

1989-12-01

386

Steroidal saponins from Tribulus terrestris.  

Science.gov (United States)

Sixteen steroidal saponins, including seven previously unreported compounds, were isolated from Tribulus terrestris. The structures of the saponins were established using 1D and 2D NMR spectroscopy, mass spectrometry, and chemical methods. They were identified as: 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-2?,3?,22?,26-tetrol-12-one (terrestrinin C), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin D), 26-O-?-d-glucopyranosyl-(25S)-furost-4-en-22?,26-diol-3,6,12-trione (terrestrinin E), 26-O-?-d-glucopyranosyl-(25R)-5?-furostan-3?,22?,26-triol-12-one (terrestrinin F), 26-O-?-d-glucopyranosyl-(25R)-furost-4-en-12?,22?,26-triol-3-one (terrestrinin G), 26-O-?-d-glucopyranosyl-(1?6)-?-d-glucopyranosyl-(25R)-furost-4-en-22?,26-diol-3,12-dione (terrestrinin H), and 24-O-?-d-glucopyranosyl-(25S)-5?-spirostan-3?,24?-diol-12-one-3-O-?-d-glucopyranosyl-(1?4)-?-d-galactopyranoside (terrestrinin I). The isolated compounds were evaluated for their platelet aggregation activities. Three of the known saponins exhibited strong effects on the induction of platelet aggregation. PMID:25172515

Kang, Li-Ping; Wu, Ke-Lei; Yu, He-Shui; Pang, Xu; Liu, Jie; Han, Li-Feng; Zhang, Jie; Zhao, Yang; Xiong, Cheng-Qi; Song, Xin-Bo; Liu, Chao; Cong, Yu-Wen; Ma, Bai-Ping

2014-11-01

387

Steroidal saponins from Dioscorea preussii.  

Science.gov (United States)

Three new steroidal saponins, named diospreussinosides A-C (1-3), along with two known ones (4, 5) were isolated from rhizomes of Dioscorea preussii. Their structures were elucidated mainly by 1D and 2D NMR spectroscopic analysis and mass spectrometry as (25S)-17?,25-dihydroxyspirost-5-en-3?-yl-O-?-L-rhamnopyranosyl-(1?4)-?-L-rhamnopyranosyl-(1?4)-?-D-glucopyranoside (1), (25S)-17?,25-dihydroxyspirost-5-en-3?-yl-O-?-L-rhamnopyranosyl-(1?4)-?-L-rhamnopyranosyl-(1?4)-[?-L-rhamnopyranosyl-(1?2)]-?-D-glucopyranoside (2), and (24S,25R)-17?,24,25-trihydroxyspirost-5-en-3?-yl-O-?-L-rhamnopyranosyl-(1?4)-?-L-rhamnopyranosyl-(1?4)-[?-L-rhamnopyranosyl-(1?2)]-?-D-glucopyranoside (3). The spirostane-type skeleton of compound 3 possessing an unusual dihydroxylation pattern on the F-ring is reported for the first time. Cytotoxicity of compounds 2-5 was evaluated against two human colon carcinoma cell lines (HT-29 and HCT 116). PMID:24928475

Tabopda, Turibio Kuiate; Mitaine-Offer, Anne-Claire; Tanaka, Chiaki; Miyamoto, Tomofumi; Mirjolet, Jean-François; Duchamp, Olivier; Ngadjui, Bonaventure Tchaleu; Lacaille-Dubois, Marie-Aleth

2014-09-01

388

Screening for anabolic steroids in urine of forensic cases using fully automated solid phase extraction and LC-MS-MS.  

Science.gov (United States)

A screening method for 18 frequently measured exogenous anabolic steroids and the testosterone/epitestosterone (T/E) ratio in forensic cases has been developed and validated. The method involves a fully automated sample preparation including enzyme treatment, addition of internal standards and solid phase extraction followed by analysis by liquid chromatography-tandem mass spectrometry (LC-MS-MS) using electrospray ionization with adduct formation for two compounds. Urine samples from 580 forensic cases were analyzed to determine the T/E ratio and occurrence of exogenous anabolic steroids. Extraction recoveries ranged from 77 to 95%, matrix effects from 48 to 78%, overall process efficiencies from 40 to 54% and the lower limit of identification ranged from 2 to 40 ng/mL. In the 580 urine samples analyzed from routine forensic cases, 17 (2.9%) were found positive for one or more anabolic steroids. Only seven different steroids including testosterone were found in the material, suggesting that only a small number of common steroids are likely to occur in a forensic context. The steroids were often in high concentrations (>100 ng/mL), and a combination of steroids and/or other drugs of abuse were seen in the majority of cases. The method presented serves as a fast and automated screening procedure, proving the suitability of LC-MS-MS for analyzing anabolic steroids. PMID:25104076

Andersen, David W; Linnet, Kristian

2014-01-01

389

Distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals in wild fish species from Dianchi Lake, China  

Energy Technology Data Exchange (ETDEWEB)

The distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals (EDCs) were studied in various tissues of wild fish species from Dianchi Lake, China. In muscle tissue, 4-tert-octylphenol, 4-cumylphenol, 4-nonlyphenol and bisphenol A were detected in fish from each sampling site, with maximal concentrations of 4.6, 4.4, 18.9 and 83.5 ng/g dry weight (dw), respectively. Steroids (estrone, 17{beta}-estradiol 17{alpha}-ethynylestradiol and estriol) were found at lower levels (<11.3 ng/g dw) and less frequently in muscle samples. The highest concentrations of steroids and phenols were found in liver, followed by those in gill and the lowest concentration was found in muscle. The field bioconcentration factors (BCFs) of phenols were calculated in fish species ranged from 18 to 97. Moreover, the measured tissue concentrations were utilized in order to estimate water concentration of steroids (4.4-18.0 ng/L). These results showed that steroidal and phenolic EDCs were likely ubiquitous contaminants in wild fish. - Highlights: > We assess the occurrence of EDCs in wild fish from Dianchi Lake, China. > We investigate the distribution of steroidal and phenolic EDCs in fish tissues. > We estimate the bioaccumulation of wild fish to steroidal and phenolic EDCs. > Steroidal and phenolic EDCs are likely ubiquitous contaminants in wild fish. - Contaminants of endocrine disrupting chemicals in wild fish.

Liu Jingliang; Wang Renmin; Huang Bin; Lin Chan; Wang Yu [Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650093 (China); Pan Xuejun, E-mail: xjpan@kmust.edu.cn [Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650093 (China)

2011-10-15

390

Distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals in wild fish species from Dianchi Lake, China  

International Nuclear Information System (INIS)

The distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals (EDCs) were studied in various tissues of wild fish species from Dianchi Lake, China. In muscle tissue, 4-tert-octylphenol, 4-cumylphenol, 4-nonlyphenol and bisphenol A were detected in fish from each sampling site, with maximal concentrations of 4.6, 4.4, 18.9 and 83.5 ng/g dry weight (dw), respectively. Steroids (estrone, 17?-estradiol 17?-ethynylestradiol and estriol) were found at lower levels (<11.3 ng/g dw) and less frequently in muscle samples. The highest concentrations of steroids and phenols were found in liver, followed by those in gill and the lowest concentration was found in muscle. The field bioconcentration factors (BCFs) of phenols were calculated in fish species ranged from 18 to 97. Moreover, the measured tissue concentrations were utilized in order to estimate water concentration of steroids (4.4-18.0 ng/L). These results showed that steroidal and phenolic EDCs were likely ubiquitous contaminants in wild fish. - Highlights: ? We assess the occurrence of EDCs in wild fish from Dianchi Lake, China. ? We investigate the distribution of steroidal and phenolic EDCs in fish tissues. ? We estimate the bioaccumulation of wild fish to steroidal and phenolic EDCs. ? Steroidal and phenolic EDCs are likely ubiquitous contaminants in wild fish. - Contaminants of endocrine disrupting chemicals in wild fish.

391

Prostate volume change after radioactive seed implantation: Possible benefit of improved dose volume histogram with perioperative steroid  

International Nuclear Information System (INIS)

Purpose: To evaluate the changes in prostate volume associated with radioactive seed implantation and identify factors that influence prostate swelling. Methods and Materials: Between June 1997 and August 1999, 161 patients implanted for prostate carcinoma at the University of California, San Francisco, had prostate volume measurements taken at 4 time points (preplan, preimplant, postimplant, postimplant dosimetry). Patient records were reviewed for treatment with perioperative steroids, hormone therapy (nHT), and external beam radiotherapy (EBRT). One and 2-way analysis of variance (ANOVA) methods were used to test differences in mean effects among patient subsets. Results: A mean 20% volume increase was noted immediately postimplant overall (p < 0.0001), and even with EBRT and/or HT. Steroids were associated with a mean volume decrease of 19.9%, by 3-4 weeks post-procedure (p < 0.0001). Without steroids, only a 3.8% mean change was seen (p = ns). Steroid use resulted in a significant increase in mean dose-volume histogram (DVH) (p = 0.001); however, this benefit was only observed among patients who did not receive steroid. A consistently high DVH occurred with steroid use. Conclusion: A significant decrease in prostate volume and improved DVH are associated with steroid use. The diminished benefit of steroid use and higher mean DVH achieved in later years suggests the existence of a significant 'learning curve' for brachytherapy procedures.rapy procedures.

392

Sex stratified neuronal cultures to study ischemic cell death pathways.  

Science.gov (United States)

Sex differences in neuronal susceptibility to ischemic injury and neurodegenerative disease have long been observed, but the signaling mechanisms responsible for those differences remain unclear. Primary disassociated embryonic neuronal culture provides a simplified experimental model with which to investigate the neuronal cell signaling involved in cell death as a result of ischemia or disease; however, most neuronal cultures used in research today are mixed sex. Researchers can and do test the effects of sex steroid treatment in mixed sex neuronal cultures in models of neuronal injury and disease, but accumulating evidence suggests that the female brain responds to androgens, estrogens, and progesterone differently than the male brain. Furthermore, neonate male and female rodents respond differently to ischemic injury, with males experiencing greater injury following cerebral ischemia than females. Thus, mixed sex neuronal cultures might obscure and confound the experimental results; important information might be missed. For this reason, the Herson Lab at the University of Colorado School of Medicine routinely prepares sex-stratified primary disassociated embryonic neuronal cultures from both hippocampus and cortex. Embryos are sexed before harvesting of brain tissue and male and female tissue are disassociated separately, plated separately, and maintained separately. Using this method, the Herson Lab has demonstrated a male-specific role for the ion channel TRPM2 in ischemic cell death. In this manuscript, we share and discuss our protocol for sexing embryonic mice and preparing sex-stratified hippocampal primary disassociated neuron cultures. This method can be adapted to prepare sex-stratified cortical cultures and the method for embryo sexing can be used in conjunction with other protocols for any study in which sex is thought to be an important determinant of outcome. PMID:24378980

Fairbanks, Stacy L; Vest, Rebekah; Verma, Saurabh; Traystman, Richard J; Herson, Paco S

2013-01-01

393

Sex differences in brain aromatase activity: genomic and non-genomic controls  

Directory of Open Access Journals (Sweden)

Full Text Available Aromatization of testosterone into estradiol in the preoptic area plays a critical role in the activation of male copulation in quail and in many other vertebrate species. Aromatase expression in quail and in other birds is higher than in rodents and other mammals, which has facilitated the study of the controls and functions of this enzyme. Over relatively long time periods (days to months, brain aromatase activity and transcription are markedly (4-6 fold increased by genomic actions of sex steroids. Initial work indicated that the preoptic aromatase activity is higher in males than in females and it was hypothesized that this differential production of estrogen could be a critical factor responsible for the lack of behavioral activation in females. Subsequent studies revealed, however, that this enzymatic sex difference might contribute but is not sufficient to explain the sex difference in behavior. Studies of aromatase activity, immunoreactivity and mRNA concentrations revealed that sex differences observed when measuring enzymatic activity are not necessarily observed when one measures mRNA concentrations. Discrepancies potentially reflect post-translational controls of the enzymatic activity. Aromatase activity in quail brain homogenates is rapidly inhibited by phosphorylation processes. Similar rapid inhibitions occur in hypothalamic explants maintained in vitro and exposed to agents affecting intracellular calcium concentrations or to glutamate agonists. Rapid changes in aromatase activity have also been observed in vivo following sexual interactions or exposure to short-term restraint stress and these rapid changes in estrogen production modulate expression of male sexual behaviors. These data suggest that brain estrogens display most if not all characteristics of neuromodulators if not neurotransmitters. Many questions remain however concerning the mechanisms controlling these rapid changes in estrogen production and their behavioral significance.

JacquesBalthazart

2011-09-01

394

Steroid isotopic standards for gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS).  

Science.gov (United States)

Carbon isotope ratio (CIR) analysis of urinary steroids using gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS) is a recognized test to detect illicit doping with synthetic testosterone. There are currently no universally used steroid isotopic standards (SIS). We adapted a protocol to prepare isotopically uniform steroids for use as a calibrant in GCC-IRMS that can be analyzed under the same conditions as used for steroids extracted from urine. Two separate SIS containing a mixture of steroids were created and coded CU/USADA 33-1 and CU/USADA 34-1, containing acetates and native steroids, respectively. CU/USADA 33-1 contains 5alpha-androstan-3beta-ol acetate (5alpha-A-AC), 5alpha-androstan-3alpha-ol-17-one acetate (androsterone acetate, A-AC), 5beta-androstan-3alpha-ol-11, 17-dione acetate (11-ketoetiocholanolone acetate, 11k-AC) and 5alpha-cholestane (Cne). CU/USADA 34-1 contains 5beta-androstan-3alpha-ol-17-one (etiocholanolone, E), 5alpha-androstan-3alpha-ol-17-one (androsterone, A), and 5beta-pregnane-3alpha, 20alpha-diol (5betaP). Each mixture was prepared and dispensed into a set of about 100 ampoules using a protocol carefully designed to minimize isotopic fractionation and contamination. A natural gas reference material, NIST RM 8559, traceable to the international standard Vienna PeeDee Belemnite (VPDB) was used to calibrate the SIS. Absolute delta(13)C(VPDB) and Deltadelta(13)C(VPDB) values from randomly selected ampoules from both SIS indicate uniformity of steroid isotopic composition within measurement reproducibility, SD(delta(13)C)<0.2 per thousand. This procedure for creation of isotopic steroid mixtures results in consistent standards with isotope ratios traceable to the relevant international reference material. PMID:18992268

Zhang, Ying; Tobias, Herbert J; Brenna, J Thomas

2009-03-01

395

Sex determination strategies in 2012: towards a common regulatory model?  

Science.gov (United States)

Sex determination is a complicated process involving large-scale modifications in gene expression affecting virtually every tissue in the body. Although the evolutionary origin of sex remains controversial, there is little doubt that it has developed as a process of optimizing metabolic control, as well as developmental and reproductive functions within a given setting of limited resources and environmental pressure. Evidence from various model organisms supports the view that sex determination may occur as a result of direct environmental induction or genetic regulation. The first process has been well documented in reptiles and fish, while the second is the classic case for avian species and mammals. Both of the latter have developed a variety of sex-specific/sex-related genes, which ultimately form a complete chromosome pair (sex chromosomes/gonosomes). Interestingly, combinations of environmental and genetic mechanisms have been described among different classes of animals, thus rendering the possibility of a unidirectional continuous evolutionary process from the one type of mechanism to the other unlikely. On the other hand, common elements appear throughout the animal kingdom, with regard to a) conserved key genes and b) a central role of sex steroid control as a prerequisite for ultimately normal sex differentiation. Studies in invertebrates also indicate a role of epigenetic chromatin modification, particularly with regard to alternative splicing options. This review summarizes current evidence from research in this hot field and signifies the need for further study of both normal hormonal regulators of sexual phenotype and patterns of environmental disruption. PMID:22357269

Angelopoulou, Roxani; Lavranos, Giagkos; Manolakou, Panagiota

2012-01-01

396

Sex determination strategies in 2012: towards a common regulatory model?  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Sex determination is a complicated process involving large-scale modifications in gene expression affecting virtually every tissue in the body. Although the evolutionary origin of sex remains controversial, there is little doubt that it has developed as a process of optimizing metabolic control, as well as developmental and reproductive functions within a given setting of limited resources and environmental pressure. Evidence from various model organisms supports the view that sex determination may occur as a result of direct environmental induction or genetic regulation. The first process has been well documented in reptiles and fish, while the second is the classic case for avian species and mammals. Both of the latter have developed a variety of sex-specific/sex-related genes, which ultimately form a complete chromosome pair (sex chromosomes/gonosomes. Interestingly, combinations of environmental and genetic mechanisms have been described among different classes of animals, thus rendering the possibility of a unidirectional continuous evolutionary process from the one type of mechanism to the other unlikely. On the other hand, common elements appear throughout the animal kingdom, with regard to a conserved key genes and b a central role of sex steroid control as a prerequisite for ultimately normal sex differentiation. Studies in invertebrates also indicate a role of epigenetic chromatin modification, particularly with regard to alternative splicing options. This review summarizes current evidence from research in this hot field and signifies the need for further study of both normal hormonal regulators of sexual phenotype and patterns of environmental disruption.

Angelopoulou Roxani

2012-02-01

397

Genetic variants of sex hormone-binding globulin and their biological consequences  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Several hormonal and metabolic factors have been found to influence the production of sex hormone-binding globulin (SHBG). In addition, twin studies have suggested that genetic factors may also contribute to variation in SHBG levels. Given the clinical significance of SHBG in regulating bioavailable sex steroid hormones, a number of studies examined the potential association between polymorphisms of SHBG gene and serum SHBG levels as well as their possible contribution in ...

2009-01-01

398

Sex hormone-binding globulin gene expression in the liver: drugs and the metabolic syndrome  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Sex hormone-binding globulin (SHBG) is the main transport binding protein for sex steroid hormones in plasma and regulates their accessibility to target cells. Plasma SHBG is secreted by the liver under the control of hormones and nutritional factors. In the human hepatoma cell line (HepG2), thyroid and estrogenic hormones, and a variety of drugs including the antioestrogen tamoxifen, the phytoestrogen, genistein and mitotane (Op’DDD) increase SHBG production and SHBG ge...

2009-01-01

399

Sexual differentiation of the zebra finch song system: potential roles for sex chromosome genes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Recent evidence suggests that some sex differences in brain and behavior might result from direct genetic effects, and not solely the result of the organizational effects of steroid hormones. The present study examined the potential role for sex-biased gene expression during development of sexually dimorphic singing behavior and associated song nuclei in juvenile zebra finches. Results A microarray screen revealed more than 2400 putative gene...

Clayton David F; Replogle Kirstin; Peabody Camilla; Tomaszycki Michelle L; Tempelman Robert J; Wade Juli

2009-01-01

400

SEX DIFFERENCES IN MOTOR BEHAVIOR IN THE MPTP MOUSE MODEL OF PARKINSON'S DISEASE  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sex differences in Parkinson's disease (PD) have been reported in humans and rodent models, with a higher incidence in men and increased severity in male rodents. The current study examined sex differences and the effects of gonadal steroid hormones in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse model of PD. Male (n=51) and female (n=50) mice were gonadectomized and received physiologic replacement with testosterone or estrogen (Experiment 1), or no hormones (Experi...

Antzoulatos, Eleni; Jakowec, Michael W.; Petzinger, Giselle M.; Wood, Ruth I.

2010-01-01

 
 
 
 
401

Sex Education for Patients  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sex education evokes a wide variety of responses in the community and from teachers. Consequently, physicians have a responsibility to present sex education material in a factual, objective way. Many people are misinformed about sexual behavior. Physicians can help patients and the community by being aware of appropriate sex education for each age group. A curriculum for sex education, and opportunities to provide sex information for patients of different ages and stages in the lifecycle, are...

Zitner, David

1985-01-01

402

Fluorochemicals used in food packaging inhibit male sex hormone synthesis  

Energy Technology Data Exchange (ETDEWEB)

Polyfluoroalkyl phosphate surfactants (PAPS) are widely used in food contact materials (FCMs) of paper and board and have recently been detected in 57% of investigated materials. Human exposure occurs as PAPS have been measured in blood; however knowledge is lacking on the toxicology of PAPS. The aim of this study was to elucidate the effects of six fluorochemicals on sex hormone synthesis and androgen receptor (AR) activation in vitro. Four PAPS and two metabolites, perfluorooctanoic acid (PFOA) and 8:2 fluorotelomer alcohol (8:2 FTOH) were tested. Hormone profiles, including eight steroid hormones, generally showed that 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH led to decreases in androgens (testosterone, dehydroepiandrosterone, and androstenedione) in the H295R steroidogenesis assay. Decreases were observed for progesterone and 17-OH-progesterone as well. These observations indicated that a step prior to progestagen and androgen synthesis had been affected. Gene expression analysis of StAR, Bzrp, CYP11A, CYP17, CYP21 and CYP19 mRNA showed a decrease in Bzrp mRNA levels for 8:2 monoPAPS and 8:2 FTOH indicating interference with cholesterol transport to the inner mitochondria. Cortisol, estrone and 17?-estradiol levels were in several cases increased with exposure. In accordance with these data CYP19 gene expression increased with 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH exposures indicating that this is a contributing factor to the decreased androgen and the increased estrogen levels. Overall, these results demonstrate that fluorochemicals present in food packaging materials and their metabolites can affect steroidogenesis through decreased Bzrp and increased CYP19 gene expression leading to lower androgen and higher estrogen levels. -- Highlights: ? Fluorochemicals found in 57% of paper and board food packaging were tested. ? Collectively six fluorochemicals were tested for antiandrogenic potential in vitro. ? Three out of six tested fluorochemicals inhibited synthesis of male sex hormones. ? Generally, levels of estrogens and cortisol stayed unaffected or increased. ? The effect on steroid synthesis was specific on gene expression of Bzrp and CYP19.

Rosenmai, A.K., E-mail: akjro@food.dtu.dk [Division of Toxicology and Risk Assessment, National Food In