Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
See detailEstonia
Havelange, Carl ULg; Christiaens, Alexandre

Book published by Les Impressions Nouvelles (2016)

Detailed reference viewed: 10 (1 ULg)
Full Text
Peer Reviewed
See detailEstradiol and Progesterone Regulate the Proliferation of Human Breast Epithelial Cells
Foidart, Jean-Michel ULg; Colin, Carine; Denoo, Xavier et al

in Fertility and Sterility (1998), 69(5), 963-9

OBJECTIVE: To study the effects of estradiol and progesterone on the proliferation of normal human breast epithelial cells in vivo. DESIGN: Double-blind randomized study. SETTING: Departments of ... [more ▼]

OBJECTIVE: To study the effects of estradiol and progesterone on the proliferation of normal human breast epithelial cells in vivo. DESIGN: Double-blind randomized study. SETTING: Departments of gynecology and of cell biology at a university hospital. PATIENT(S): Forty postmenopausal women with untreated menopause and documented plasma FSH levels of >30 mIU/mL and estradiol levels of <20 pg/mL. INTERVENTION(S): Daily topical application to both breasts of a gel containing a placebo, estradiol, progesterone, or a combination of estradiol and progesterone during the 14 days preceding esthetic breast surgery or excision of a benign lesion. MAIN OUTCOME MEASURE(S): Plasma and breast tissue concentrations of estradiol and progesterone. Epithelial cell cycles were evaluated in normal breast tissue by counting mitoses and performing quantitative proliferating cell nuclear antigen immunolabeling analyses. RESULT(S): Increasing the estradiol concentration enhanced the number of cycling epithelial cells, whereas increasing the progesterone concentration significantly limited the number of cycling epithelial cells. CONCLUSION(S): Exposure to progesterone for 14 days reduced the estradiol-induced proliferation of normal breast epithelial cells in vivo. [less ▲]

Detailed reference viewed: 23 (0 ULg)
Full Text
Peer Reviewed
See detailEstradiol contributes to the postnatal demasculinization of female Japanese quail (Coturnix coturnix japonica).
Balthazart, Jacques ULg; Schumacher, M.

in Hormones and Behavior (1984), 18(3), 287-97

Two experiments were performed to characterize the process of postnatal demasculinization in Japanese quail. In the first experiment, it was shown that estradiol (E2) can complete female demasculinization ... [more ▼]

Two experiments were performed to characterize the process of postnatal demasculinization in Japanese quail. In the first experiment, it was shown that estradiol (E2) can complete female demasculinization during the first 4 weeks of life. By contrast, E2 did not demasculinize sexual behavior and cloacal gland in neonatally castrated males. Neonatally gonadectomized females preferentially performed mount attempts when tested in their home cage by comparison to a test arena. In Experiment 2, E2 Silastic implants (40-mm) maintained full copulatory behavior in castrated males but not in females. This large dose of E2 did not demasculinize adult sexually active birds (males or females) even if treatment lasted for 1 month. It is concluded that E2 can demasculinize sexual behavior only in females and only if treatment is performed in very young birds. [less ▲]

Detailed reference viewed: 22 (1 ULg)
Full Text
Peer Reviewed
See detailEstradiol Pharmacokinetics after Transdermal Application of Patches to Postmenopausal Women: Matrix Versus Reservoir Patches
Reginster, Jean-Yves ULg; Donazzolo, Y.; Brion, N. et al

in Climacteric : The Journal of the International Menopause Society (2000), 3(3), 168-75

OBJECTIVE: A new matrix 17 beta-estradiol transdermal patch incorporating lauric acid to improve estradiol skin absorption has been designed for hormone replacement therapy. Estradiol pharmacokinetics ... [more ▼]

OBJECTIVE: A new matrix 17 beta-estradiol transdermal patch incorporating lauric acid to improve estradiol skin absorption has been designed for hormone replacement therapy. Estradiol pharmacokinetics obtained with the prototype, its industrial counterpart, a matrix-type, System 50, and a reservoir-type, Estraderm TTS 50, transdermal patch have been compared. Each device delivers 50 micrograms estradiol daily. METHODS: Twenty postmenopausal women received each of the four formulations for 3 days in a Latin-square design and with a minimum 4-day wash-out period between treatments. Estradiol plasma concentrations were measured by radioimmunoassay at 6, 12, 24, 48 and 72 h after application. RESULTS: The prototype patch and its industrial counterpart showed no significant difference in estradiol delivery, with 72-h systemic exposure to estradiol similar to that of the reservoir patch but greater than that of the reference matrix formulation, with average baseline-corrected concentrations (SEM) of 35 (4), 32 (3), 32 (2) and 19 (1.8) pg/ml, respectively. In addition, they ensured more stable delivery, with coefficients of variation of plasma estradiol concentrations (12-72 h) of 29, 41, 63 and 84%, respectively. All matrix patches demonstrated the same patients to be poor estradiol absorbers, different from those encountered with the reservoir patch type, despite an improved estradiol bioavailability with the lauric acid-containing matrix patch. CONCLUSION: Matrix patches incorporating lauric acid led to estradiol plasma levels more stable than with the reference matrix and reservoir patches, and greater than those with the reference matrix patch. [less ▲]

Detailed reference viewed: 18 (1 ULg)
Full Text
Peer Reviewed
See detailEstradiol rapidly activates male sexual behavior and affects brain monoamine levels in the quail brain
Cornil, Charlotte ULg; Dalla, C.; Papadopoulou-Daifoti, Z. et al

in Behavioural Brain Research (2006), 166(1), 110-123

Steroids are generally viewed as transcription factors binding to intracellular receptors and activating gene transcription. Rapid cellular effects mediated via non-genomic mechanisms have however been ... [more ▼]

Steroids are generally viewed as transcription factors binding to intracellular receptors and activating gene transcription. Rapid cellular effects mediated via non-genomic mechanisms have however been identified and one report showed that injections of estradiol rapidly stimulate chemoinvestigation and mounting behavior in castrated male rats. It is not known whether such effects take place in other species and what are the cellular underlying mechanisms. We show here that a single injection of estradiol (500 wg/kg) rapidly and transiently activates copulatory behavior in castrated male quail pre-treated with a dose of testosterone behaviorally ineffective by itself. The maximal behavioral effect was observed after 15 min. In a second experiment, the brain of all subjects was immediately collected after behavioral tests performed 15 min after injection. The preoptic area-hypothalamus (HPOA), hindbrain, telencephalon and cerebellum were isolated and monoamines measured by HPLC-ED. Estradiol increased levels of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) and 5-HIAA/serotonin ratios in the telencephalon and hindbrain independently of whether animals had mated or not. Estradiol also affected these measures in HPOA and cerebellum but this effect was correlated with the level of sexual activity so that significant effects of the treatment only appeared when sexual activity was used as a covariate. Interactions between estradiol effects and sexual activity were also observed for dopamine in the HPOA and for serotonin in the hindbrain and cerebellum. Together, these data demonstrate that a single estradiol injection rapidly activates male sexual behavior in quail and that this behavioral effect is correlated with changes in monoaminergic activity. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 30 (3 ULg)
Full Text
Peer Reviewed
See detailEstradiol stimulation of Pulsatile gonadotropin-releasing hormone secretion in vitro: Correlation with perinatal exposure to sex steroids and induction of sexual precocity in vivo
Matagne, V.; Rasier, G.; LEBRETHON, Marie-Christine ULg et al

in Endocrinology (2004), 145(6), 2775-2783

Our aim was to study the effect of estradiol (E2) on pulsatile GnRH secretion in vitro in relation to sex and development. When hypothalamic explants obtained from 5- and 15-d-old female rats were exposed ... [more ▼]

Our aim was to study the effect of estradiol (E2) on pulsatile GnRH secretion in vitro in relation to sex and development. When hypothalamic explants obtained from 5- and 15-d-old female rats were exposed to E2 (10(-7) m), a reduction of GnRH interpulse interval (IPI) occurred but not at 25 and 50 d of age. This effect was prevented by the estrogen receptor antagonist ICI 182.780 and the AMPA/kainate receptor antagonist DNQX but not by the AMPA and N-methyl-D-aspartate receptor antagonists SYM 2206 and MK-801. E2 did not affect GnRH IPI in hypothalamic explants obtained from male rats. Therefore, the possible relation between the female-specific effects of E2 in vitro and perinatal sexual differentiation was investigated. When using explants obtained from female rats masculinized through testosterone injection on postnatal d 1, E2 was no longer effective in vitro at 5 and 15 d. In addition, with explants obtained from male rats demasculinized through perinatal aromatase inhibitor treatment, E2 became capable of decreasing GnRH IPI in vitro at 15 d. To study the possible pathophysiological significance of early hypothalamic E2 effects, female rats received a single E2 injection on postnatal d 10. This resulted in reduced GnRH IPI in vitro on d 15 as well as advancement in age at vaginal opening and first estrus. In conclusion, E2 decreases the GnRH IPI in the immature female hypothalamus in vitro through a mechanism that depends on perinatal brain sexual differentiation and that could be involved in some forms of female precocious puberty. [less ▲]

Detailed reference viewed: 24 (2 ULg)
Full Text
Peer Reviewed
See detailEstradiol, a key endocrine signal in the sexual differentiation and activation of reproductive behavior in quail
Balthazart, Jacques ULg

in Comparative Biochemistry & Physiology Part A : Molecular & Integrative Physiology (2007, August), 148(Suppl. 1), 27

Detailed reference viewed: 13 (2 ULg)
Full Text
Peer Reviewed
See detailEstradiol, a key endocrine signal in the sexual differentiation and activation of reproductive behavior in quail.
Balthazart, Jacques ULg; Cornil, Charlotte ULg; Charlier, Thierry ULg et al

in Journal of Experimental Zoology. Part A, Ecological Genetics and Physiology (2009), 311(5), 323-45

In Japanese quail, estrogen's effects on sexual behavior can be divided into three classes based on the underlying mechanisms and time-course of action and release. During embryonic life, the embryonic ... [more ▼]

In Japanese quail, estrogen's effects on sexual behavior can be divided into three classes based on the underlying mechanisms and time-course of action and release. During embryonic life, the embryonic ovary secretes large amounts of estrogens. In contrast to what is observed in mammals where sexual differentiation essentially proceeds via masculinization of the males, in quail, females are demasculinized by their endogenous ovarian estrogens, an effect that can be blocked by injection of an aromatase inhibitor and mimicked in male embryos by an injection of estradiol. In adulthood, testosterone secreted by the testes is converted into estrogens by the preoptic aromatase. Locally produced estrogens activate male sexual behavior largely through the activation of estrogen receptors resulting in the transcription of a variety of genes, including brain aromatase (genomic effect). Both changes in estrogen production and action are observed within latencies ranging from a few hours to a few days, and are completely reversible. Additionally, brain aromatase activity can be modulated within minutes by calcium-dependent phosphorylations, triggered by variations in glutamatergic neurotransmission. These rapid changes in aromatase activity affect with relatively short latencies (10-15 min) the expression of male sexual behavior in quail and also in mice. Overall, the effects of estrogens on sexual behavior can thus be categorized into three classes: organizational (irreversible genomic action during ontogeny), activational (reversible genomic action during adulthood) and rapid nongenomic effects. Rapid and slower changes in brain aromatase activity match well with the two modes of estrogen action on behavior and provide temporal variations in the estrogens' bioavailability that should be able to support the entire range of established effects for this steroid. [less ▲]

Detailed reference viewed: 29 (11 ULg)
Full Text
See detailEstrategias de una traducción literal
Willson, Patricia ULg

Article for general public (2015)

Detailed reference viewed: 32 (11 ULg)
Full Text
See detailEstrategias sociopreventivas del hooliganismo
Comeron, Manuel ULg

in Colome, Gabriel (Ed.) Politica y Deporte (2001)

Une analyse comparative en Europe (Angleterre, Belgique, France, Espagne): évolution des politiques sportives, le sport et l'Etat, la lutte contre le hooliganisme, les stratégies préventives, le sport ... [more ▼]

Une analyse comparative en Europe (Angleterre, Belgique, France, Espagne): évolution des politiques sportives, le sport et l'Etat, la lutte contre le hooliganisme, les stratégies préventives, le sport comme spectacle médiatique. [less ▲]

Detailed reference viewed: 147 (1 ULg)
See detailEstrogen activation revisited: control of local metabolism in the brain
Charlier, Thierry ULg

Scientific conference (2012)

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailEstrogen and pain: a study in aromatase knock-out mice using the formalin model.
Multon, Sylvie ULg

Conference (2004, September)

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
See detailEstrogen Receptor β Activation Rapidly Modulates Male Sexual Motivation through the Transactivation of Metabotropic Glutamate Receptor 1a
Seredynski, Aurore L; Balthazart, Jacques ULg; Ball, Gregory F et al

in Journal of Neuroscience (2015), 35(38), 13110-23

In addition to the transcriptional activity of their liganded nuclear receptors, estrogens, such as estradiol (E2), modulate cell functions, and consequently physiology and behavior, within minutes ... [more ▼]

In addition to the transcriptional activity of their liganded nuclear receptors, estrogens, such as estradiol (E2), modulate cell functions, and consequently physiology and behavior, within minutes through membrane-initiated events. The membrane-associated receptors (mERs) underlying the acute effects of estrogens on behavior have mostly been documented in females where active estrogens are thought to be of ovarian origin. We determined here, by acute intracerebroventricular injections of specific agonists and antagonists, the type(s) of mERs that modulate rapid effects of brain-derived estrogens on sexual motivation in male Japanese quail. Brain aromatase blockade acutely inhibited sexual motivation. Diarylpropionitrile (DPN), an estrogen receptor β (ERβ)-specific agonist, and to a lesser extent 17α-estradiol, possibly acting through ER-X, prevented this effect. In contrast, drugs targeting ERα (PPT and MPP), GPR30 (G1 and G15), and the Gq-mER (STX) did not affect sexual motivation. The mGluR1a antagonist LY367385 significantly inhibited sexual motivation but mGluR2/3 and mGluR5 antagonists were ineffective. LY367385 also blocked the behavioral restoration induced by E2 or DPN, providing functional evidence that ERβ interacts with metabotropic glutamate receptor 1a (mGluR1a) signaling to acutely regulate male sexual motivation. Together these results show that ERβ plays a key role in sexual behavior regulation and the recently uncovered cooperation between mERs and mGluRs is functional in males where it mediates the acute effects of estrogens produced centrally in response to social stimuli. The presence of an ER-mGluR interaction in birds suggests that this mechanism emerged relatively early in vertebrate history and is well conserved. Significance statement: The membrane-associated receptors underlying the acute effects of estrogens on behavior have mostly been documented in females, where active estrogens are thought to be of ovarian origin. Using acute intracerebroventricular injections of specific agonists and antagonists following blockade of brain aromatase, we show here that brain-derived estrogens acutely facilitate male sexual motivation through the activation of estrogen receptor β interacting with the metabotropic glutamate receptor 1a. This behavioral effect occurring within minutes provides a mechanistic explanation of how an estrogen receptor not intrinsically coupled to intracellular effectors can signal from the membrane to govern behavior in a very rapid fashion. It suggests that different subtypes of estrogen receptors could regulate the motivation versus performance aspects of behavior. [less ▲]

Detailed reference viewed: 23 (5 ULg)
Full Text
Peer Reviewed
See detailEstrogen Receptor-Beta in Quail: Cloning, Tissue Expression and Neuroanatomical Distribution
Foidart, Agnès ULg; Lakaye, Bernard ULg; Grisar, Thierry ULg et al

in Journal of Neurobiology (1999), 40(3), 327-42

A partial estrogen receptor-beta (ERbeta) cDNA had been previously cloned and sequenced in Japanese quail. The 3'- and 5'-rapid amplification of cDNA ends techniques were used here to identify a cDNA ... [more ▼]

A partial estrogen receptor-beta (ERbeta) cDNA had been previously cloned and sequenced in Japanese quail. The 3'- and 5'-rapid amplification of cDNA ends techniques were used here to identify a cDNA sequence of the quail ERbeta that contains a complete open reading frame. For the first time in an avian species, this cDNA sequence and the corresponding amino acid sequence are described. They are compared with the known ERbeta sequences previously described in mammals and with the ERalpha sequences identified in a selection of mammalian and avian species. The analysis by Northern blotting of the ERbeta mRNA expression in the brain and kidneys revealed the presence of several transcripts. The presence of ERbeta identified by reverse transcriptase-polymerase chain reaction demonstrated a widespread distribution quite different from the distribution of ERalpha. The complete neuroanatomical distribution of ERbeta mRNA as determined by in situ hybridization with 35S- and 33P-labeled oligoprobes is also presented. Transcripts are present in many nuclei implicated in the control of reproduction such as the medial preoptic nucleus, the nucleus striae terminalis, and the nucleus taeniae, the avian homologue of the amygdala. These data demonstrate the presence of ERbeta in a nonmammalian species and indicate that the (neuro)-anatomical distribution of this receptor type has been conserved in these two classes of vertebrates. The role of this receptor in the control of reproduction and other physiological processes should now be investigated. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Peer Reviewed
See detailEstrogen replacement therapy and inhibition of bone resorption
Reginster, Jean-Yves ULg; Sarlet, N; Albert, Adelin ULg et al

in Revue du Rhumatisme et des Maladies Osteo-Articulaires (1992), 59

Detailed reference viewed: 12 (1 ULg)
Full Text
Peer Reviewed
See detailEstrogen-deficient female but not male aromatase knockout (ArKO) mice exhibit "depressive-like" symptoms
Bakker, Julie ULg; Dalla, C.; Antoniou, K. et al

in Hormones & Behavior (2004, June), 46(1), 127

Detailed reference viewed: 17 (2 ULg)