References of "Closset, Jean"
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See detailComparison of three methods for fractionation and enrichment of low molecular weight proteins for SELDI-TOF-MS differential analysis
De Bock, Muriel ULg; De Seny, Dominique ULg; Meuwis, Marie-Alice ULg et al

in Talanta (2010), 82

In most diseases, the clinical need for serum/plasma markers has never been so crucial, not only for diagnosis, but also for the selection of the most efficient therapies, as well as exclusion of ... [more ▼]

In most diseases, the clinical need for serum/plasma markers has never been so crucial, not only for diagnosis, but also for the selection of the most efficient therapies, as well as exclusion of ineffective or toxic treatment. Due to the high sample complexity, prefractionation is essential for exploring the deep proteome and finding specific markers. In this study, three different sample preparation methods (i.e., highly abundant protein precipitation, restricted access materials (RAM) combined with IMAC chromatography and peptide ligand affinity beads) were investigated in order to select the best fractionation step for further differential proteomic experiments focusing on the LMW proteome (MW inferior to 40,000 Da). Indeed, the aim was not to cover the entire plasma/serum proteome, but to enrich potentially interesting tissue leakage proteins. These three methods were evaluated on their reproducibility, on the SELDI-TOF-MS peptide/protein peaks generated after fractionation and on the information supplied. The studied methods appeared to give complementary information and presented good reproducibility (below 20%). Peptide ligand affinity beads were found to provide efficient depletion of HMW proteins and peak enrichment in protein/peptide profiles. [less ▲]

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See detailDevelopment and validation of a radioimmunoassay for thyrotropin in cattle
Guyot, Hugues ULg; Sulon, Joseph ULg; Beckers, Jean-François ULg et al

in Journal of Veterinary Diagnostic Investigation (2007), 19(6), 643-651

In mammals, thyrotropin, or thyroid-stimulating hormone (TSH), assay is used for the diagnosis of primary hypothyroidism. Hypothyroidism is the most common type of thyroid disorder in cattle. The aim of ... [more ▼]

In mammals, thyrotropin, or thyroid-stimulating hormone (TSH), assay is used for the diagnosis of primary hypothyroidism. Hypothyroidism is the most common type of thyroid disorder in cattle. The aim of this study was to develop and validate, under physiologic and pathologic conditions, a radioimmunoassay (RIA) for bovine TSH (bTSH). Double RIA was performed with purified bTSH and specific bovine antiserum. Laboratory validation included research of minimal detection limit, accuracy, and reproducibility. The physiologic validation included a thyrotropin-releasing hormone (TRH) challenge performed on euthyroid cows and a follow-up of bTSH concentration over a 24-hour period. Furthermore, bTSH concentration was assayed in a large population of healthy dairy and beef cows to define reference interval. The pathologic validation was made by assaying bTSH and thyroid hormones on healthy and goitrous newborn calves. The minimum detection limit (MDL) for bTSH assay was 1.3 microU/ml. The recovery was 101% to 106%. The intra- and interassay coefficients of variation (CVs) ranged from 5% to 11% and 11% to 15%, respectively. The RIA covered the whole range of physiologic bTSH values, as shown by bTSH values induced by TRH-challenge. A pulsatile secretion of bTSH was observed, accompanied by a diurnal variation with lower night values than day values. Reference intervals of bTSH ranged from 1.3 to 13.0 microU/ml for beef and dairy breeds. Finally, bTSH easily discriminated goitrous newborn calves from healthy ones, leading to the definition of a cutoff value of 35 microU/ml. The bTSH assay positively reacted to physiologic and pathologic conditions. The accuracy and precision of the RIA were satisfying. [less ▲]

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See detailPrincipes des microdamiers à ADN et applications potentielles en sciences vétérinaires
Thomas, A.; Closset, Jean ULg; Bureau, Fabrice ULg et al

in Annales de Médecine Vétérinaire (2005), 149

Microarray technology is a miniaturized biotechnological tool with potential applications for study and analysis of multiple molecular compounds as proteins, lipids, carbohydrates or nucleic acids. The ... [more ▼]

Microarray technology is a miniaturized biotechnological tool with potential applications for study and analysis of multiple molecular compounds as proteins, lipids, carbohydrates or nucleic acids. The nucleic acids microarray technology focuses interest of scientists for fifteen years because of its huge potential as regard to the scientific research, clinical diagnosis, and development of new drugs. Only DNA microarrays are investigated in this paper. Born from the conjunction of micro-electronics, biochemistry, molecular biology, and image processing, microarrays allow to analyse several thousands of genetic information simultaneously. Thanks to this new tool, it is possible in parallel to identify, to even proportion, a considerable number of nucleic acid sequences contained in a biological sample (blood, biopsy, water, food, etc). This article proposes, after having considered the operating mode of the microarrays, to understand their quality standards as well as their advantages and disadvantages. The two following parts are devoted to the place the microarrays occupy in scientific research and in the establishment of a clinical diagnosis. Finally the last part evaluates prospects the microarrays offer in veterinary sciences. [less ▲]

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See detailNew features in the treatment of androgen-independent prostate cancer.
Closset, Jean ULg; Ammar, Hayet; Nguyen, Viet-Ha et al

in Current Pharmaceutical Design (2004), 10(5), 513-22

Prostate cancer develops from clones that are already present as early as thirty-five years of age, when circulating concentrations of androgens are high. The progression of the disease is low and the ... [more ▼]

Prostate cancer develops from clones that are already present as early as thirty-five years of age, when circulating concentrations of androgens are high. The progression of the disease is low and the cancer is diagnosed at a more advanced age. Prostate cancer evolves from an androgen dependant stage to stage where it escapes from all anti-androgenic treatments. The patient usually dies within two years following the diagnosis of advanced cancer. Therefore, it is of great interest to develop new therapies for androgen independent prostate cancer. The androgen independent evolution of prostate cancer is a complex phenomenon at the cellular and molecular levels. It includes an increased sensitivity to growth factors, the control of proliferation pathways, apoptotic and survival pathways as well as the control of angiogenesis. Epidemiological studies have also suggested that certain vitamins or phyto-oestrogens could protect against prostate cancer development. The present review attempts to present an overview of the fundamental research in cellular signalling which could be interesting as target for the treatment of androgen independent prostate cancer. Also the potential interest of non-androgenic steroids was reviewed for the same goal. [less ▲]

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See detailProstatic androgen repressed message-1 (PARM-1) may play a role in prostatic cell immortalisation.
Cornet, Anne ULg; Hanon, Emmanuel; Reiter, Eric R et al

in Prostate (The) (2003), 56(3), 220-30

BACKGROUND: Prostatic androgen-repressed message-1 (PARM-1) has been cloned from the prostate. The transcript of the PARM-1 gene is overexpressed during regression of the prostate after androgen ... [more ▼]

BACKGROUND: Prostatic androgen-repressed message-1 (PARM-1) has been cloned from the prostate. The transcript of the PARM-1 gene is overexpressed during regression of the prostate after androgen withdrawal. The regulation of PARM-1 by androgens is limited to this organ. We have studied the effects of PARM-1 overexpression in malignant prostate cells. METHODS: The PARM-1 cDNA was introduced into the rat cancer cell line MAT LyLu along with a doxycycline-dependent regulator. RESULTS: Maximal expression of PARM-1 (fivefold induction) was achieved by incubating the cells with 2 microM doxycycline for 48 hr. A study investigating the effect of PARM-1 overexpression on the transcription of 588 genes has shown that the TLP1 gene (encoding rat telomerase protein component 1) was the most up-regulated (fourfold). In addition, a dose-dependent increase in telomerase activity was observed in cells overexpressing PARM-1. In vivo, the androgen-deprived prostate showed an increased TLP1 level and increased telomerase activity. CONCLUSIONS: Increased telomerase activity is often associated with the immortalisation of cancer cell lines, particularly prostatic ones. This could mean that PARM-1 is involved, via increased telomerase activity, in a survival program enabling certain prostatic cells to resist apoptosis, thus conferring a selective advantage to pre-cancerous or cancerous cells. [less ▲]

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See detailRadioimmunoassay of porcine pepsinogen
Banga-Mboko, Henri; Sulon, Joseph ULg; Closset, Jean ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2001), 5(1), 25-26

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See detailGenes upregulated during castration-induced rat prostatic apoptosis: cloning and characterization of new cDNAs.
Bruyninx, M.; Ammar, H.; Reiter, E. et al

in BJU International (2000), 85(9), 1134-42

OBJECTIVE: To isolate new cDNAs corresponding to genes whose expression is increased during castration-induced rat prostate apoptosis. MATERIALS AND METHODS: Differential display of mRNAs from 3-day ... [more ▼]

OBJECTIVE: To isolate new cDNAs corresponding to genes whose expression is increased during castration-induced rat prostate apoptosis. MATERIALS AND METHODS: Differential display of mRNAs from 3-day castrated and normal rat ventral prostates was used to identify differentially expressed clones. Northern blots were hybridized to confirm the positive regulation of the candidates and to follow the change in their expression in the involuting rat prostate, and in thymocytes of dexamethazone-treated rats. RESULTS: Five cDNAs were cloned: one encoding ribosomal protein L7, one coding for the insulin-like growth factor binding protein-3 (IGFBP-3), and three whose products are unknown. After castration, all five genes had expression kinetics that closely paralleled the proportion of prostatic epithelial cells undergoing apoptosis. The gene encoding L7 and two of the unknown genes were also upregulated in glucocorticoid-induced programmed death in thymocytes. In addition to the IGFBP-3 gene, those coding for proteins IGFBP-4, -5 and -6 were also overexpressed in the involuting prostate of androgen-deprived rats. CONCLUSION: Five new genes were identified that are up-regulated during castration-induced rat prostate apoptosis, three of which are potentially involved in the common intracellular pathway leading to programmed cell death. [less ▲]

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See detailA novel messenger ribonucleic acid homologous to human MAGE-D is strongly expressed in rat Sertoli cells and weakly in Leydig cells and is regulated by follitropin, lutropin, and prolactin.
Hennuy, Benoît ULg; Reiter, E.; Cornet, Anne ULg et al

in Endocrinology (2000), 141(10), 3821-31

We have cloned a novel complementary DNA whose expression was decreased in rat Sertoli cell cultures after treatment with FSH. This complementary DNA encodes a protein of 570 amino acids and shares 92 ... [more ▼]

We have cloned a novel complementary DNA whose expression was decreased in rat Sertoli cell cultures after treatment with FSH. This complementary DNA encodes a protein of 570 amino acids and shares 92% homology with the human MAGE-D protein. In contrast to other MAGE genes (A, B, or C), we have shown that MAGE-D expression was ubiquitous in healthy rat tissues. In the seminiferous tubules, the MAGE-D was expressed in Sertoli cells but not in germ cells as demonstrated by RT-PCR and in situ hybridization, whereas for the other MAGE genes, expression has been shown to be restricted to germ cells. Interestingly, MAGE-D was also detected for the first time in the female gonad by Northern blotting. In MLTC-1 cells (mouse Leydig tumor cell line-1), LH and PRL stimulated MAGE-D expression. Using hypophysectomized rats, it was confirmed that FSH decreased MAGE-D expression, whereas LH and PRL increased MAGE-D messenger RNA level in the whole testis most probably through a direct action on Leydig cells. As MAGE-D is present in both the seminiferous compartment and interstitium and hormonally regulated in each, it is possible that it has specific functions in each compartment during the development and the maintenance of the testis. [less ▲]

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See detailEffects of pituitary hormones on the prostate.
Reiter, E.; Hennuy, Benoît ULg; Bruyninx, M. et al

in Prostate (1999), 38(2), 159-65

BACKGROUND: Although essential, androgens alone are not sufficient to induce normal growth and functionality of the prostate. Nonandrogenic hormones must also be involved in the proliferation of the ... [more ▼]

BACKGROUND: Although essential, androgens alone are not sufficient to induce normal growth and functionality of the prostate. Nonandrogenic hormones must also be involved in the proliferation of the prostate cancer cells which do not respond to antiandrogenic therapy and which thus become androgen-independent. Prolactin, but also growth hormone and luteinizing hormone, are potentially able to act on both normal and abnormal prostatic cells. METHODS: In this review we summarize data from the literature concerning the physiological and pathological implications of prolactin, growth hormone, and luteinizing hormone on the prostate. RESULTS: In rodent prostates, prolactin and growth hormone can induce a variety of effects independently of androgens (e.g., transactivation of certain genes, or synthesis of the major secretion products). Moreover, hyperprolactinemia is responsible for inflammation and dysplasia of the gland, while growth hormone promotes the development of prostate tumors in vivo in the mouse and rat. Growth hormone acts on the gland directly, through prostatic growth hormone receptors, and/or indirectly via the stimulation of insulin-like growth factor-I (IGF-I) synthesis in the liver. Luteinizing hormone receptor is expressed in rat and human prostates. Luteinizing hormone increases the amount of various transcripts in the rat prostate through an androgen-independent pathway. CONCLUSIONS: Prolactin, growth hormone, and luteinizing hormone, alone or synergistically with androgens, play physiologically significant roles in the normal prostate. The involvement of these hormones in the development of benign prostatic hyperplasia and prostatic carcinoma is an issue that needs to be addressed. [less ▲]

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See detailCharacterization of menin from leucocytes of normal and men-1 affected individuals
Poncin, Jacques ULg; Closset, Jean ULg; Legros, Jean-Jacques ULg et al

in 81st Annual Meeting of the Endocrine society - Abstract book (1999)

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See detailGènes impliqués dans l'apoptose prostatique provoquée par un déficit androgénique
Bruyninx, Marc; Cornet, Anne ULg; Hennuy, Benoît ULg et al

in Medecine Sciences : M/S (1998), 14(5), 572-579

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See detailGrowth hormone and prolactin stimulate androgen receptor, insulin-like growth factor-I (IGF-I) and IGF-I receptor levels in the prostate of immature rats.
Reiter, E.; Bonnet, Pierre ULg; Sente, B. et al

in Molecular & Cellular Endocrinology (1992), 88(1-3), 77-87

In this study we investigated the involvement of several different pituitary hormones on rat prostate development. 22-day-old Wistar rats, hypophysectomized (hypox) at 19 days of age were supplemented ... [more ▼]

In this study we investigated the involvement of several different pituitary hormones on rat prostate development. 22-day-old Wistar rats, hypophysectomized (hypox) at 19 days of age were supplemented with highly purified human prolactin (hPRL), human luteinizing hormone (hLH), porcine follicle-stimulating hormone (pFSH), and bovine growth hormone (bGH) or with saline. Quantitative analysis of RNAs shows that treatment with either PRL or GH increases significantly steady-state mRNAs levels of the following genes in the prostate: androgen receptor (AR) (respectively 3.5- and 4.8-fold above hypox controls), IGF-I (5- and 2.7-fold), and IGF-I receptor (2.9- and 2.3-fold). LH and FSH, by contrast, have negative effects on these parameters. To test whether the enhancing effect of PRL and GH on AR-mRNA abundance was followed by increased content in the protein itself, binding assays were performed with the androgen agonist [3H]R1881 (131 and 153 fmol/mg protein while hypox controls contained 110 fmol/mg protein). In addition to the well-documented presence of prolactin receptors in prostatic tissues, we have further demonstrated, by means of nuclease S1 protection assays plus dot- and Northern-blot analyses, that a GH receptor mRNA is produced in the immature rat prostate. Moreover, we observed not only strong lactogenic but also purely somatogenic binding to be occurring in the immature prostates. Finally, we have studied IGF-I mRNA content in separated epithelial/stromal cell fractions and have concluded that IGF-I expression is principally located in the prostatic stroma. Taken together, these results suggest that PRL and GH are involved in regulating AR synthesis, at least partially by direct action on the organ. In this context IGF-I appears as a paracrine factor playing a role in epithelium/stroma interactions during prostatic development. [less ▲]

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See detailPurification and characterization of a bovine pregnancy-associated glycoprotein
Zoli, André Pagnah; Beckers, Jean-François ULg; Wouters-Ballman, Patricia et al

in Biology of Reproduction (1991), 45(1), 1-10

A 67000 Mr bovine pregnancy-associated glycoprotein (bPAG) has been isolated from fetal cotyledons and purified to homogeneity by HPLC. The purification was monitored by a double immunodiffusion test and ... [more ▼]

A 67000 Mr bovine pregnancy-associated glycoprotein (bPAG) has been isolated from fetal cotyledons and purified to homogeneity by HPLC. The purification was monitored by a double immunodiffusion test and by RIA in conjunction with an antiserum raised against a crude fraction of placenta-specific antigens. The molecular weight of bPAG was estimated to be 67000 by SDS-PAGE. The isoelectric points (pI) of the four isoforms, determined by high-resolution analytical electrofocusing in polyacrylamide gel, were 4.4, 4.6, 5.2, and 5.4. The carbohydrate content of the bPAG consisted of approximately 10.02 +/- 1.09% neutral sugar and variant amounts of sialic acid (from 0.29 +/- 0.06% in the most basic isoform to 2.1 +/- 0.31% in the most acidic isoform). A specific antiserum was raised against the purified bPAG. A specific RIA showed that the bPAG was antigenically unrelated to BSA, alphafetoprotein (AFP), and human schwangerschafts-spezifischen (pregnancy-specific) beta 1 glycoprotein (SP1). According to some characteristics (e.g. the molecular weight), the purified bPAG may correspond to a form of the pregnancy-specific protein B previously described by Sasser and colleagues (Biol Reprod 1986; 35:936-942). [less ▲]

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See detailEndocrine, paracrine and autocrine factors in the maturation and functional development of the testis
Closset, Jean ULg; Dombrowicz, David; Vandenbroeck, Marc et al

in Bulletin et Mémoires de l'Académie Royale de Médecine de Belgique (1989), 144(1-2), 196-7

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See detailPITUITARY-HORMONES DEPENDENT EXPRESSION OF INSULIN-LIKE GROWTH FACTOR-I AND FACTOR-II IN THE IMMATURE HYPOPHYSECTOMIZED RAT TESTIS
Closset, Jean ULg; Gothot, André ULg; SENTE, Béatrice et al

in Molecular Endocrinology (1989), 3(7), 1125-1131

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See detailL'hormone de croissance placentaire : caractérisation et signification biochimiques et physiologique.
Hennen, Georges ULg; Frankenne, Francis; Igout, Ahmed ULg et al

in Annales d'Endocrinologie (1988, October)

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See detailDetermination of porcine plasma follitropin levels during superovulation treatment in cows
Demoustier, M.; Beckers, Jean-François ULg; Van Der Zwalmen, P. et al

in Theriogenology (1988), 30(2), 379-386

Porcine follicle stimulating hormone (pFSH) and porcine luteinizing hormone (pLH), are widely used to induce superovulation in cows. An advantage of this treatment is that the LH:FSH ratio can be varied ... [more ▼]

Porcine follicle stimulating hormone (pFSH) and porcine luteinizing hormone (pLH), are widely used to induce superovulation in cows. An advantage of this treatment is that the LH:FSH ratio can be varied to optimize the growth of the ovarian follicles. However, due to the relatively short half-life of FSH, the superovulatory treatment requires numerous injections. A performant radioimmunoassay system (sensitivity=0.2 ng/ml plasma) was used to determine plasma pFSH levels in cows that were superovulated with 2 daily injections of 4 Armour Units (A.U.) of pFSH for 4 d. From plasma profiles, the half-life and the disappearance of pFSH were estimated at 5 h and at 10 to 12 h, respectively, confirming the necessity of using two daily injections. [less ▲]

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See detailPLACENTAL GROWTH-HORMONE - SIGNIFICANCE RELATIVE TO PITUITARY GROWTH-HORMONES AND PLACENTAL-LACTOGEN HORMONE
Hennen, Georges ULg; Frankenne, Francis ULg; Scippo, Marie-Louise ULg et al

in Reproduction Nutrition Development (1988), 28(6B), 1699-1706

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