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See detailEffects of the Nonsteroidal Inhibitor R76713 on Testosterone-Induced Sexual Behavior in the Japanese Quail (Coturnix Coturnix Japonica)
Balthazart, Jacques ULg; Evrard, L.; Surlemont, C.

in Hormones & Behavior (1990), 24(4), 510-31

A new triazole derivative, R76713 (6-[4-chlorophenyl)(1H-1,2,4-triazol-1-yl)methyl]-1-methyl-1H- benzotriazole), was recently shown to inhibit aromatase selectively without affecting other steroid ... [more ▼]

A new triazole derivative, R76713 (6-[4-chlorophenyl)(1H-1,2,4-triazol-1-yl)methyl]-1-methyl-1H- benzotriazole), was recently shown to inhibit aromatase selectively without affecting other steroid-metabolizing enzymes and without interacting with estrogen, progestin, or androgen receptors. This compound was tested for its capacity to intefere with the induction of copulatory behavior by testosterone (T) in castrated Japanese quail (Coturnix coturnix japonica). In a first experiment, R76713 inhibited (range 0.01 to 1 mg/kg) the activation of sexual behavior by T silastic implants and hypothalamic aromatase activity in castrated male quail in a dose-dependent manner. The 5 alpha- and 5 beta- reductases of T were not systematically affected. Stereotaxic implantation of R76713 in the medial preoptic area similarly blocked the behavior activated by systemic treatment with T, demonstrating that central aromatization of androgen is implicated in the activation of behavior. These inhibiting effects of R76713 on behavior were observed when implants were placed in the medial part of the nucleus preopticus medialis, confirming the implication of this brain area in the control of male copulatory behavior. Finally, the behavioral inhibition produced by R76713 could be reversed by simultaneous treatment with a dose of estradiol, which was not behaviorally effective by itself. This suggests that the behavioral deficit induced by the inhibitor was specifically due to the suppression of estrogen production. This also shows that the activation of copulatory behavior probably results from the interaction of androgens and estrogens at the brain level, as the two treatments separately providing these hormonal stimuli (T with the aromatase inhibitor on one hand and a low dose of estradiol on the other hand) had almost no behavioral effects but they synergized to activate copulation when given concurrently. These data confirm the critical role of preoptic aromatase in the activation of reproductive behavior and demonstrate that R76713 is a useful tool for the in vivo study of estrogen-dependent processes. [less ▲]

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See detailEffects of the Noradrenergic Neurotoxin Dsp-4 on Luteinizing Hormone Levels, Catecholamine Concentrations, Alpha 2-Adrenergic Receptor Binding, and Aromatase Activity in the Brain of the Japanese Quail
Balthazart, Jacques ULg; Ball, G. F.

in Brain Research (1989), 492(1-2), 163-75

Previous investigations have established that DSP-4 reliably enhances the activating effects of testosterone on copulatory behavior in adult male quail. In the present study, we wanted to clarify the ... [more ▼]

Previous investigations have established that DSP-4 reliably enhances the activating effects of testosterone on copulatory behavior in adult male quail. In the present study, we wanted to clarify the neurochemical changes that parallel these behavioral effects and to determine whether DSP-4 also affects non-behavioral steroid-dependent sexually dimorphic reproductive processes. We first showed using the Palkovits microdissection technique combined with assay by high-performance liquid chromatography (HPLC) that DSP-4 specifically depletes norepinephrine in several nuclei of the brain such as the medial preoptic nucleus, the ventromedial nucleus of the hypothalamus or the intercollicular nucleus but leaves intact the noradrenergic innervation in other areas such as the infundibulum or nucleus accumbens. Other amines such as dopamine and serotonin were not affected by the drug. Surprisingly DSP-4 did not decrease the binding of tritiated p-aminoclonidine in any of the brain areas which were studied by quantitative autoradiography. This suggests that most of the alpha 2-adrenergic receptors are located at the postsynaptic level but alternative interpretations are discussed. Testosterone treatment of castrated birds specifically reduced the density of alpha 2-adrenergic receptors in the dorsal infundibulum and in the medial mammillary nucleus. The possible relations of this receptor change to the control of luteinizing hormone (LH) secretion are discussed. Finally it was shown that DSP-4 treatment decreases plasma LH levels (which reveals the stimulatory effect of norepinephrine on LH secretion) but increases the testosterone-induced aromatase activity in the preoptic area. This latter effect could be one of the mechanisms by which DSP-4 potentiates copulatory behavior in testosterone-treated quail. [less ▲]

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See detailEffects of the presence of free lime nodules into concrete: experimentation and modelling
Courard, Luc ULg; Degée, Hervé ULg; Darimont, Anne ULg

in Cement and Concrete Research (2014), 64

When nodules of lime are embedded into concrete, the expansion accompanying the transformation of CaO into Ca(OH)2 induces stresses and strains in both the lime nodule and in the concrete matrix. The ... [more ▼]

When nodules of lime are embedded into concrete, the expansion accompanying the transformation of CaO into Ca(OH)2 induces stresses and strains in both the lime nodule and in the concrete matrix. The concrete cover thickness, the diameter and the shape of the lime nodule as well as the mechanical characteristics of concrete and lime are the key parameters influencing the development of internal pressure and hence controlling the risk of cracking or pop-out. In order to study the effect of lime into cementitious concretes, laboratory investigations and modelling have been performed and show that the minimum cover thickness necessary to avoid the development of the pop-out phenomenon is estimated of the order of half the diameter of the inclusion. This is coming from the observation that expansion happens inside the porosity of the hydrated lime Ca(OH)2: ESEM and DRX analysis confirm the effect of confinement in the development of crystals. [less ▲]

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See detailEffects of the roll forming process on the mechanical properties of thin-walled sections made of non linear metallic materials
Rossi, Barbara ULg; Boman, Romain ULg; Degée, Hervé ULg

in Proceedings of the 6th International Conference on Thin Walled Structures: ICTWS2011, Timisoara 5-7 September 2011 (2011, September 05)

It is well known that the cold-forming process is likely to significantly enhance the mechanical properties of the profile by strain hardening leading to increased resistance compared to a resistance ... [more ▼]

It is well known that the cold-forming process is likely to significantly enhance the mechanical properties of the profile by strain hardening leading to increased resistance compared to a resistance assessment based on nominal properties. It is thus necessary to accurately determine the mechanical properties after the cold process of fabrication. The knowledge on these enhanced properties is rather good for profiles made of traditional construction steel (carbon steel with yield strength between 200 and 400 MPa) characterized by an elasticplastic behaviour. However less information is available for profiles made of materials exhibiting a non linear stress-strain relationship. In this context, the paper presents a parametric study on roll-profiled channel sections. For that purpose, the finite element code METAFOR developed at the LTAS division of the University of Liège is used to simulate the forming process of profiles made of high strength steel and of stainless steel. In the simulations, different values of the radius to thickness ratio of the corners are considered. The results of the numerical simulations are expressed in terms of resulting proof strength in the corners versus the radius to thickness ratio for the different materials. They are finally compared to existing predictive formulations. Additional considerations are also given on the forming process itself (i.e. on the configuration of the rolls or on the springback). [less ▲]

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See detailEffects of the social conditions of housing through testing on cocaine-induced contextual sensitisation and conditioned locomotion in C57BL/6J mice
Michel, Alexa ULg; Tirelli, Ezio ULg

in Progress in Neuro-Psychopharmacology & Biological Psychiatry (2002), 26(6), 1185-1191

The potential differential effects of isolated and collective housing through the testing phase on sensitisation to cocaine-induced locomotion, the subsequent conditioned locomotion and the context ... [more ▼]

The potential differential effects of isolated and collective housing through the testing phase on sensitisation to cocaine-induced locomotion, the subsequent conditioned locomotion and the context-dependent expression of sensitisation were examined in C57BL/6J male mice. [less ▲]

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See detailEffects of the stage of maturation and varieties on the chemical composition of banana and plantain peels
Happi Emaga, Thomas ULg; Andrianaivo, Rado; Wathelet, Bernard ULg et al

in Food Chemistry (2007), 103(2), 590-600

A study of the chemical composition of six varieties of fruit peels of the banana and plantain: dessert banana (Musa AAA), plantain (Musa AAB) cooking banana (Musa ABB) and hybrid (Musa AAAB) at three ... [more ▼]

A study of the chemical composition of six varieties of fruit peels of the banana and plantain: dessert banana (Musa AAA), plantain (Musa AAB) cooking banana (Musa ABB) and hybrid (Musa AAAB) at three stages of ripeness, was carried out in order to explore their potential applications. The varieties did not affect chemical constituents in a consistent manner. Peel of the six varieties was rich in total dietary fibre (TDF) (40-50%). The protein content in peel of the banana and plantain was 8-11%. Leucine, valine, phenylalanine and threonine were essential amino acids in significant quantities: Lysine was the limiting amino acid. The content of lipid varied from 2.2% to 10.9% and was rich in polyunsaturated fatty acids, particularly linoleic acid and alpha-linolenic acid. Potassium was the most significant mineral element. Peel of plantain was richer in starch than were the banana peels. Maturation of fruits involved increase in soluble sugar content and, at the same time, decrease in starch. The degradation of the starch under the action of the endogenous enzymes, may explain the increase in the soluble sugar content. Further investigations on the composition and the physiological functions (using animal-feeding experiments) of these dietary fibres must be considered. (c) 2006 Elsevier Ltd. All rights reserved. [less ▲]

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See detailEffects of therapeutic measures taken during the aura
Schoenen, Jean ULg

in Amery, W. K.; Wauquier, A. (Eds.) The Prelude of the Migraine Attack (1986)

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See detailEffects of thiazolidinediones on tumor necrosis factor R alpha induced inflammatory cytokine expression
Desmet, Christophe ULg; Warsée, Barbara; Mélotte, D. et al

in Pflügers Archiv : European Journal of Physiology (2004), 447

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See detailEffects of thiol reagents on Streptomyces K15 DD-peptidase-catalysed reactions
Leyh-Bouille, Mélina; Nguyen-Distèche, Martine ULg; Bellefroid-Bourguignon, Catherine et al

in Biochemical Journal (1987), 241(3), 893-897

The 26,000-Mr DD-peptidase of Streptomyces K15 binds one equivalent of thiol reagents as 5,5'-dithiobis-(2-nitrobenzoate) or p-chloromercuribenzoate (pCMB). Derivatization of the DD-peptidase by pCMB ... [more ▼]

The 26,000-Mr DD-peptidase of Streptomyces K15 binds one equivalent of thiol reagents as 5,5'-dithiobis-(2-nitrobenzoate) or p-chloromercuribenzoate (pCMB). Derivatization of the DD-peptidase by pCMB decreases the efficacy of the initial binding of the ester carbonyl donor Ac2-L-Lys-D-Ala-D-lactate to the enzyme (K), the rate of enzyme acylation by the donor (K+2) and the rate of enzyme deacylation (k+3). However, the value of the k+2/k+3 ratio, and therefore the percentage of total enzyme which, at saturating concentrations of the donor, is present as acyl-enzyme at the steady state of the reaction, are not modified. The enzyme's binding sites for pCMB and benzylpenicillin are not mutually exclusive. But, when compared with the native enzyme, the pCMB-derivatized enzyme undergoes acylation by benzylpenicillin with a decreased second-order-rate constant (k+2/K) value and gives rise to a penicilloyl adduct of increased stability. Since the acyl-enzyme mechanism is not annihilated by pCMB derivatization, it is proposed that basically, and like all the other DD-peptidases/penicillin-binding proteins so far characterized, the Streptomyces K15 DD-peptidase is an active-site-serine enzyme. [less ▲]

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See detailEffects of three avocado/soybean unsaponifiable mixtures on human chondrocytes metabolism
Henrotin, Yves ULg; Labasse, A; Zheng, SX et al

in Arthritis and Rheumatism (1996), 39

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See detailEffects of three avocado/soybean unsaponifiable mixtures on metalloproteinases, cytokines and prostaglandin E2 production by human articular chondrocytes.
Henrotin, Yves ULg; Labasse, A. H.; Jaspar, J. M. et al

in Clinical Rheumatology (1998), 17(1), 31-9

The in-vitro effects of avocado and soybean unsaponifiable residues on neutral metalloproteinase activity, cytokines and prostaglandin E2 (PGE2) production by human articular chondrocytes were ... [more ▼]

The in-vitro effects of avocado and soybean unsaponifiable residues on neutral metalloproteinase activity, cytokines and prostaglandin E2 (PGE2) production by human articular chondrocytes were investigated. Avocado and soybean unsaponifiable residues were mixed in three ratios: 1:2 (A1S2), 2:1 (A2S1) or 1:1 (A2S2). Freshly isolated human chondrocytes were cultured for 72 h in the absence or presence of interleukin-1beta, (IL-1beta) (17 ng/ml), with or without unsaponifiable residue mixtures at a concentration of 10 microg/ml. A/S unsaponifiable residues were also tested separately at concentrations of 3.3, 6.6 and 10 microg/ml. All A/S unsaponifiable mixtures reduced the spontaneous production of stromelysin, interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E2 (PGE2) by chrondrocytes. At concentrations of 3.3 and 6.6 microg/ml, A/S residues, tested separately, were potent inhibitors of the production of IL-8 and PGE2. Nevertheless, only avocado residue inhibited IL-6 production at these concentrations. A/S unsaponifiable mixtures had a more pronounced inhibitory effect on cytokine production than avocado or soybean residues added alone. As anticipated, IL-1beta induced a marked release of collagenase, stromelysin, IL-6, IL-8 and PGE2. A/S unsaponifiable mixtures partially reversed the IL-1 effects on chrondrocytes. These findings suggest a potential role for A/S unsaponifiable extracts in mitigating the deleterious effects of IL-1beta: on cartilage. [less ▲]

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See detailEffects of thromboxane A2 receptor antagonists and COX inhibitors on osteogenic sarcome cell-induced platelet aggregation
De Leval, X.; Delarge, J.; Neven, P. et al

Poster (2001, June 01)

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See detailEffects of thromboxane A2 receptor antagonists and thromboxane synthase inhibitors on osteogenic sarcoma cell induced platelet aggregation
De Leval, X.; Benoît, V.; Neven, P. et al

Poster (2002, October)

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See detailEffects of thromboxane A2 receptor antagonists and thromboxane synthase inhibitors on osteogenic sarcoma cell induced platelet aggregation
De Leval, X.; Benoît, V.; Neven, P. et al

Poster (2002, May)

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See detailEffects of thromboxane A2 receptor antagonists and thromboxane synthase inhibitors on osteogenic sarcoma cell-induced platelet aggregation
De Leval, X.; Benoit, V.; Neven, P. et al

Poster (2002, March 02)

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See detailEffects of thromboxane A2 receptor antagonists and thromboxane synthase inhibitors on osteogenic sarcoma cell-induced platelet aggregation
De Leval, X.; Benoit, V.; Neven, P. et al

in Fundamental & Clinical Pharmacology (2002)

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