References of "Beckers, Jean-François"
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See detailImmunocytochemical localization of vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) in the bovine ovary
Hulshof, S. C. J.; Dijkstra, G.; Van der Beek, E. M. et al

in Biology of Reproduction (1994), 50(3), 553-560

The distribution of the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) was studied immunocytochemically in bovine ovaries from 3 mo of gestation up to and including puberty ... [more ▼]

The distribution of the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) was studied immunocytochemically in bovine ovaries from 3 mo of gestation up to and including puberty, and from adult cows at three stages of the estrous cycle. The appearance of VIP and NPY immunoreactivity of 4.5-6 mo of gestation coincided with the onset of follicular development. In contrast to NPY, VIP was first found in the cortex. Both VIP and NPY immunoreactivity increased with age. From 9 mo of gestation onwards, VIP and NPY were found around blood vessels and non-vascular smooth muscle cells, in the stroma near preantral follicles, and in the theca externa of antral follicles. In addition, VIP-positive cells were observed exclusively in the granulosa layer of the preovulatory follicle at the time of the LH surge. The distribution of VIP- and NPY-immunoreactive fibers in the ovary may point to an effect of these neuropeptides on various physiological processes, including follicle development and ovarian blood flow. In addition, the presence of VIP-positive cells in the granulosa layer of the preovulatory follicle is indicative of a role for VIP in ovulation. [less ▲]

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See detailLe point sur la production d’embryons in vitro: limitations et perspectives de la recherche
Thonon, Fabienne; Ectors, Fabien ULg; Delval, Alain et al

in Annales de Médecine Vétérinaire (1994), 138(1), 33-40

Recent progress in gamete biology and early embryo development was responsible for great evolution of reproduction techniques in farm animals. Among these techniques, in vitro production of bovine embryos ... [more ▼]

Recent progress in gamete biology and early embryo development was responsible for great evolution of reproduction techniques in farm animals. Among these techniques, in vitro production of bovine embryos was developed from slaughterhouse ovaries. This method has been used for individual animals. However, large variations in results were observed, due to several factors, including reproductive state and age of the donor. Inspite of this limitation, in vitro production of bovine embryos may be helpful, when slaughtering of valuable cows is recommended eg for brucellosis disease. Researches are purchased in order to increase the number of oocytes obtained per "elite" cow and to improve the ability of in vitro embryos to support freezing. [less ▲]

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See detailPreservation of Oocyte and Granulosa Cell Morphology in Bovine Preantral Follicles Cultured in Vitro
Figueiredo, J. R.; Hulshof, S. C.; Van den Hurk, R. et al

in Theriogenology (1994), 41(6), 1333-46

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and energy ... [more ▼]

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and energy substrata (i.e., pyruvate and glutamine) on the morphology of cultured preantral follicles were investigated. It was shown that addition of a mixture of pyruvate, glutamine and hypoxantine to the culture medium increased the percentage of follicles with an intact oocyte from 29.4 to 78.6%. Morphological criteria are described to discriminate between normal and degenerated preantral follicles during culture by inverted microscopy. In addition, the importance of histological evaluation to judge the quality of oocyte and granulosa cells is demonstrated. [less ▲]

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See detailModification of immunoreactive EGF receptor after acute tubular necrosis induced by tobramycin or cisplatin
Leonard, I.; Zanen, J.; Nonclercq, D. et al

in Renal Failure (1994), 16(5), 583-608

Acute tubular necrosis induced by aminoglycoside antibiotics and various other nephrotoxins is followed by a regenerative process which leads to the restoration of damaged tubules. Several lines of ... [more ▼]

Acute tubular necrosis induced by aminoglycoside antibiotics and various other nephrotoxins is followed by a regenerative process which leads to the restoration of damaged tubules. Several lines of evidence indicate that tubular regeneration is mediated by polypeptide growth factors such as epidermal growth factor (EGF). Previous studies devoted to cisplatin nephrotoxicity have shown that this agent causes tubular cystic degeneration possibly related to an impairment of renal tissue repair. Thus, we examined on a comparative basis the time course of the regenerative response subsequent to tubular damage induced by tobramycin or cisplatin, particular attention being paid to renal EGF and its receptor. Female Sprague-Dawley rats (160-180 g body weight) were treated during 4 consecutive days with daily doses of 200 mg/kg tobramycin i.p. (BID) or 2 mg/kg cisplatin (once a day). Sham-treated rats were given 0.9% NaCl i.p. following the same protocol. Groups of experimental animals (n = 5-10) were terminated at increasing time intervals (1, 4, 7, 14, 21, 60 days) after cessation of treatment. One hour prior to sacrifice, each individual received i.p. 200 mg/kg 5-bromo-2'-deoxyuridine (BrdU) for the immunohistochemical demonstration of cell proliferation. Blood was collected at the time of sacrifice in order to assess glomerular filtration rate by measuring serum creatinine and BUN levels. Kidneys were analyzed with respect to total EGF determined by RIA in renal tissue homogenates, and soluble EGF was assayed in extracts prepared by centrifugation. Renal tissue was processed for the immunohistochemical detection of S-phase cells, of EGF, of EGF receptors, and of the intermediate filament vimentin, the latter being used as a marker of epithelium dedifferentiation. In absence of nephrotoxic alterations, EGF was immunolocalized in distal tubules, whereas EGF receptor immunostaining was seen in proximal tubules cells. Vimentin immunostaining was confined to glomeruli and blood vessels. Tobramycin and cisplatin caused acute tubular necrosis in proximal convoluted tubules and proximal straight tubules, respectively. Tissue damage was accompanied by renal dysfunction reflected by an elevation of serum creatinine and BUN levels. Tubular necrosis was followed by a proliferative response indicative of tubular regeneration. Regenerative hyperplasia was associated with a reduction of total immunoreactive EGF due to a decrease of tissue-bound proEGF. Tubules undergoing regenerative repair were characterized by a disappearance of EGF receptors and the presence of immunoreactive vimentin. In tobramycin-treated rats, renal dysfunction lasted for 4-7 days and was fully reversible, as indicated by the return of serum markers to normal values. [less ▲]

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See detailClonage par greffe de blastomère: naissance d'un premier veau
Ectors, Fabien ULg; Delval, Alain; Touati, Kamal ULg et al

in Annales de Médecine Vétérinaire (1993), 137(8), 573-574

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See detailDevelopment of a combined mechanical and enzymatic method for the isolation of intact preantral follicles from fetal, calf and adult bovine ovaries
Figueiredo, José Ricardo; Hulshof, S. C. J.; Van den Hurk, R. et al

in Theriogenology (1993), 40(4), 789-799

The isolation of preantral follicles from the ovaries of bovine fetuses, calves and adult cows was performed using a simple, rapid mechanical and enzyme method. The ovaries were cut into small pieces with ... [more ▼]

The isolation of preantral follicles from the ovaries of bovine fetuses, calves and adult cows was performed using a simple, rapid mechanical and enzyme method. The ovaries were cut into small pieces with a tissue chopper. Then, the suspension was filtered successively through 500 and 100 μm nylon mesh filters. This simple mechanical procedure resulted in large numbers of isolated preantral follicles: 2,142 ± 254; 512 ± 92 and 298 ± 54 from the ovaries of bovine fetuses, calves and cows, respectively. In addition, the ovarian fragments between 100 and 500 μm were suspended in 10 ml of M199 Hepes medium plus 5% FCS and divided into 2 equal parts: one portion was used for collagenase treatment (200 U/ml) for 20 minutes, while the other served as a control. Collagenase treatment resulted in 841 ± 161; 216 ± 51 and 52 ± 17 preantral follicles from fetuses, calves and cows, respectively, compared with 312 ± 86; 52 ± 15 and 10 ± 2 in the control group. The use of collagenase with ovarian fragments selected by filtration as a method for increasing the rate of recovery of preantral follicles is described here. [less ▲]

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See detailLe clonage par transfert de noyau dans l'espèce bovine: premiers résultats
Ectors, Francis ULg; Ectors, Fabien ULg; Delval, Alain et al

in Bulletin et Mémoires de l'Académie Royale de Médecine de Belgique (1993), 148

In 1987, Prather et al. have performed the first embryo cloning by nuclear transfer in the bovine species. Since, many researchers try to develop and to apply the technique. While the enucleation of the ... [more ▼]

In 1987, Prather et al. have performed the first embryo cloning by nuclear transfer in the bovine species. Since, many researchers try to develop and to apply the technique. While the enucleation of the recipient oocyte, the injection of the donor blastomere and the fusion procedure are now well controlled, on the other hand, maturation and activation as the development and freezing of the cloned embryos need tobe more investigated. The cloned embryo is more fragile. An increase in embryonic mortality is observed after transfer in a recipient cow. [less ▲]

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See detailClonage par transfert de noyau dans l'espèce bovine: premiers résultats
Ectors, Fabien ULg; Delval, Alain; Touati, Kamal ULg et al

in Annales de Médecine Vétérinaire (1993), 137(6), 427-431

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See detailLight and Electron microscopic immunolocalization of Bovine pregnancy-associated glycoprotein in the Bovine Placentome
Demez, Pierre ULg; Zolli, A. P.; Beckers, Jean-François ULg et al

in 1st Joint meeting of the Royal Microscopical society and the Belgian Societies for Cell biology, clinical cytology, Electron Microscopy and pathology-Abstract book (1993)

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See detailComparison between culture of bovine embryos in vitro versus development in rabbit oviducts and in vivo
Ectors, Fabien ULg; Thonon, Fabienne; Delval, Alain et al

in Livestock Production Science (1993), 36

The aim of this work was to evaluate the efficiency of different embryo culture methods for in vitro embryo production: development in co-culture with bovine oviductal epithelial cells (BOEC), in BOEC ... [more ▼]

The aim of this work was to evaluate the efficiency of different embryo culture methods for in vitro embryo production: development in co-culture with bovine oviductal epithelial cells (BOEC), in BOEC conditioned medium (CM) or in rabbit oviducts, versus in vivo produced embryos. There was no significant difference in terms of percentages of cleaved and 8-cell stages obtained between CM and BOEC. In CM, 24.8% of the cleaved embryos became blastocysts. In BOEC, 14.5% of the cleaved embryos became blastocysts. Among the 190 zygotes transferred in the rabbit oviducts, 127 have been recovered 5 days later, and 17.4% became blastocysts. There was no significant difference in term of blastocyst formation between the development in rabbit and in BOEC. However, there was a significant difference between the CM group and the two other groups. The numbers of cells in blastocysts from different sources were investigated: in vivo blastocysts contained 107 cells assumed to be 100%, in vitro blastocysts developed in rabbit oviduct 100.1 cells (93.3%), BOEC blastocysts 90.8 cells (84.6%) and CM blastocysts 72.3 cells (67.3%). This study confirmed earlier works on the oviduct effect on blastocyst quality in terms of development rate and cell number. [less ▲]

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See detailEffect of estradiol supplementation on superovulation in swamp buffalo
Uoc, N. T.; Nguyen, B. X.; Ty, L. V. et al

in Theriogenology (1992), 38(3), 471-478

The effect of estradiol-17β (E2) supplementation on superovulation with (PMSG) or (FSH) was investigated in Swamp buffalo. Sixty-eight buffalo were treated in seven groups. Group 1 served as control and ... [more ▼]

The effect of estradiol-17β (E2) supplementation on superovulation with (PMSG) or (FSH) was investigated in Swamp buffalo. Sixty-eight buffalo were treated in seven groups. Group 1 served as control and was superovulated by standard PMSG or FSH treatment used in routine bovine embryo transfer protocols. Group 2 was superovulated by standard PMSG regimen plus two injections of E2 at a 48 h interval beginning one day before the onset of gonadotropin treatment (short-term supplementation) for a total dosage of 2.5 mg E2; Groups 3 and 4 received the same regimen as Group 2, but in doses of 5.0 and 7.5 mg E2, respectively. Group 5 received the standard FSH regimen (40% LH). Group 6 received short-term E2 (7.5 mg) supplementation of FSH-p. Group 7 was superovulated by standard FSH regimen (40% LH) plus three injections of E2 at 48–72 h intervals beginning five days before the onset of gonadotropin treatment (long-term supplementation) for a total dosage of 7.5 mg E2. The number of corpora lutea (CL) and follicles ≥ 8 mm in diameter were recorded by palpation per rectum and after slaughter. The mean numbers of CL and follicles were 0.99, 5.8, 8.0, 10.6, 4.0, 3.9, 8.1 and 0.25, 6.8, 6.2, 6.2, 1.6, 0.0, 4.1 for Groups 1, 2, 3, 4, 5, 6, 7, respectively. In Group 7, the rates of nonsurgical and postmortem embryo recovery were 46 and 90.4%, respectively and 54.4% of the collected ova were fertilized. These results indicate the possibility of producing viable embryos in buffalo by using E2 supplementation for the gonadotropin treatment. [less ▲]

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See detailEffects of repeated use of progestagen-PMSG treatment for estrus control in dairy goats out of breeding season
Baril, Gérard; Remy, Benoît ULg; Vallet, J. C. et al

in Reproduction in Domestic Animals (1992), 27(3), 161-168

Contents: In order to analyze the effects of repeated use of progestagen-PMSG treatment, estrus and pregnancy results have been analyzed for 1989 in a Saânen dairy goat herd in which breeding takes place ... [more ▼]

Contents: In order to analyze the effects of repeated use of progestagen-PMSG treatment, estrus and pregnancy results have been analyzed for 1989 in a Saânen dairy goat herd in which breeding takes place each year out of season after FGA/PMSG treatment. After the first 1989 treatment (169 goats), percentage of goats showing estrus and kidding have been lower for 59 multiparous than for 46 primiparous and 64 nulliparous females. Moreover, when 38 goats are treated for a second time in 1989, 44.7% exhibited estrus vs 71.0% after the first treatment (P < 0.05). The PMSG binding level before the 1st 1989 treatment is higher for multiparous (17.5 ± 23.1%) than nulli and primiparous (-0.06 ± 0.7 and 1.2 ± 1.9%) and is increased for all parities after treatment (23.2 ± 26.4 after vs 5.7 ± 15.0% before, P < 0.01). For nulliparous and primiparous females; PMSG binding levels are not different for pregnant or not pregnant nulliparous and primiparous goats. On the opposite, PMSG binding rates are higher in non pregnant (25.7 ± 23.3) than in pregnant multiparous goats (6.5 ± 15.9) (P < 0.01). However, when the binding rate is ≤ 5.12% (computerized distributions) multiparous goats exhibit estrus and pregnancy at levels not different from nulliparous or primiparous females (% estrus 95.8 vs 100 or 97.8%, % pregnancy 66.7 vs 70.3 and 63.0% respectively). Repeated use of PMSG during the female life or during one given year leads to active immunization against PMSG (as measured by percentage of binding of PMSG in plasma) decreasing the efficiency of ovarian stimulation out of breeding season. [less ▲]

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See detailRadioimmunoassay of a Bovine Pregnancy-Associated Glycoprotein in Serum: Its Application for Pregnancy Diagnosis
Zoli, André Pagnah; Guilbault, Louis A; Delahaut, Philippe et al

in Biology of Reproduction (1992), 46(1), 83-92

A sensitive and specific double-antibody RIA for a bovine pregnancy-associated glycoprotein (bPAG) is described. The limit of detection was 0.2 ng/ml. The assay was specific for bPAG in that pituitary and ... [more ▼]

A sensitive and specific double-antibody RIA for a bovine pregnancy-associated glycoprotein (bPAG) is described. The limit of detection was 0.2 ng/ml. The assay was specific for bPAG in that pituitary and placental gonadotropic hormones and other placental or serum proteins assayed in serial dilutions did not cross-react. The RIA allowed measurement of bPAG in placental extracts, fetal serum, fetal fluids, and serum or plasma of pregnant cows. About 20% of unbred heifers and nonpregnant cows had detectable levels ranging from 0.30 +/- 0.09 to 0.50 +/- 0.17 ng/ml (mean +/- SD), and 15% of bull sera showed higher concentrations (3.01 +/- 1.73 ng/ml) of bPAG or bPAG-like protein. Variations among animals was observed in fetal serum bPAG concentrations. Bovine PAG was detected in maternal peripheral blood at Day 22 of pregnancy (mean +/- SD, 0.38 +/- 0.13 ng/ml) in some animals and at Day 30 in all pregnant cows. Peripheral serum bPAG levels increased progressively to 3.60 +/- 1.73 ng/ml (mean +/- SD) at Day 30 of pregnancy, to 24.53 +/- 8.81 ng/ml at Day 120, and to 1551.91 +/- 589.68 ng/ml at Day 270. Peak concentration of bPAG was 2462.42 +/- 1017.88 ng/ml and it occurred 1-5 days prior to parturition. After delivery, bPAG concentrations decreased steadily to 499.63 +/- 267.20 ng/ml at Day 14 postpartum (pp), 10.12 +/- 7.84 ng/ml at Day 60 pp, and 1.44 +/- 1.08 ng/ml at Day 90 pp. The undetectable concentration (less than 0.20 ng/ml) was reached by Day 100 +/- 20 pp. An investigation undertaken in Holstein heifers, Holstein cows, and Hereford cows used as recipients for purebred Holstein embryos supplied evidence of the influence of breed of recipient and sex of fetuses on peripheral concentrations of bPAG. A herd of 430 Holstein-Friesian heifers that had received transferred embryos were bled at Day 35 postestrus (pe) for measurement of bPAG. The bPAG was detected in 287 of 430 serum samples analyzed. By rectal palpation performed at Day 45 pe, 267 heifers with detectable levels of bPAG at Day 35 pe were confirmed to be pregnant as were 3 of 143 heifers previously diagnosed as not pregnant by RIA. These results suggest that detection of this placental-specific antigen in the serum could be used as a specific serological method for early pregnancy diagnosis in cattle from 28 days after breeding. [less ▲]

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See detailLight and electron microscopic immunolocalization of bovine pregnancy-associated glycoprotein in the bovine placentome.
Zoli, A.; Demez, Pierre ULg; Beckers, Jean-François ULg et al

in Biology of Reproduction (1992), 46(4), 623-9

A bovine pregnancy-associated glycoprotein (bPAG) of 67 kDa has previously been isolated from bovine fetal cotyledons. The objective of this study was to determine the cytological localization of that ... [more ▼]

A bovine pregnancy-associated glycoprotein (bPAG) of 67 kDa has previously been isolated from bovine fetal cotyledons. The objective of this study was to determine the cytological localization of that protein in the placentomes and possibly the cells responsible for its production. Highly specific antisera raised against pure bPAG were used to demonstrate the cellular localization of the protein in bovine placentomes by light and electron microscopic techniques. Strong immunostaining was observed exclusively in the cytoplasm of large binucleate cells present predominantly in fetal cotyledonary tissue (villi). Some smaller weakly immunostained cells were also present in caruncular epithelium. By ultrastructural immunogold procedures, the protein was detected only within amorphous cytoplasmic granules. Granules of identical size, but weakly labeled, were found on the maternal side. All cells containing labeled granules were binucleate. These results suggest that bPAG is probably synthesized by trophoblast binucleate cells and stored in granules prior to delivery into the maternal circulation after cell migration. [less ▲]

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See detailObservations sur l'utilisation de traitements gonadotropes répétés chez la chèvre laitière
Baril, Gérard; Remy, Benoît ULg; Vallet, J. C. et al

in Annales de Zootechnie (1992), 41(3-4), 291-296

Observations on the repeated use of gonadotropin treatments in the dairy goat. Our studies have attempted to determine if the absence of oestrus observed in some goats after fluorogestone acetate-pregnant ... [more ▼]

Observations on the repeated use of gonadotropin treatments in the dairy goat. Our studies have attempted to determine if the absence of oestrus observed in some goats after fluorogestone acetate-pregnant mare serum gonadotropin (FGA-PMSG) treatments could be due to its repeated use. An experiment was carried out in a Saanen flock, in which she-goats were submitted to FGA-PMSG treatment each year. The first treatment of the year was performed on 169 shegoats between March and August 1989. Of the females diagnosed as non-pregnant following the first treatment, 38 were treated a second time during the same period. The proportion of females which went into oestrus after the first treatment was lower in 59 multiparous goats than in 64 nulliparous and in 46 primiparous goats (64.4 vs 100 and 97.8%; P < O.Oi). For the she-goats treated twice, the percentage of females which went into oestrus after the second treatment was lower than that observed after the first treatment (44.7 vs 71.0%; P < 0.05). The presence of anti-PMSG antibodies in plasma was investigated in blood samples taken before and after each treatment. Results are expressed as % of radioactive PMSG bound by 10 pl of blood plasma. Before the first treatment, the percentage of bound PMSG was higher in multiparous than in nulliparous and primiparous goats (17.5 t 23.1 vs -0.06 t 0.7 ; 1.2 ± 1.9 ; P < 0.01), and increased after treatment for all parities. In goats treated twice, the percentage of bound PMSG before the second treatment was higher than that observed before first treatment (22.8 t 23. vs 11.2 f 19.7; P < 0.05). For both treatments, females which did not come into oestrus showed a percentage of bound PMSG which was significantly higher than that of goats in which oestrus was observed (multiparous first treatment: 30.5 f 23.6 vs 1I 2. 9 20. 1 %; she-goats in second treatment: 33.9 ± 23.1 vs 9.2 ± 14.5T.). When the percentage of bound PMSG before treatment was low (< 5°l) in multiparous goats, the oestrus and kidding rates after the first treatment did not differ from those observed in nulliparous and primiparous goats. The decrease in the efficiency of the treatments was therefore not due to the age of animals. The repeated use of FGA-PMSG during the lifetime of goats or within the same year is followed by an increase in the levels of antibodies against PMSG. The presence of those antibodies may explain the decrease in the efficiency of these treatments in inducing and synchronizing oestrus. [less ▲]

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See detailIdentification of the major pregnancy-specific antigens of cattle and sheep as inactive members of the aspartic proteinase family
Xie, Sancai; Low, Boon G.; Nagel, Robert J. et al

in Proceedings of the National Academy of Sciences of the United States of America (1991), 88(22), 10247-10251

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component of Mr ... [more ▼]

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component of Mr 67,000. Molecular cloning of its cDNA reveals that the antigen belongs to the aspartic proteinase family and has greater than 50% amino acid sequence identity to pepsin, cathepsin D, and cathepsin E. The inferred sequences of the ovine and bovine polypeptides show approximately 73% identity to each other. Critical amino acid substitutions at the active site regions suggest that both proteins are enzymatically inactive. The antigen is a product of trophoblast binucleate cells that invade maternal endometrium at implantation sites. [less ▲]

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See detailAre Antibodies Responsible for a Decreased Superovulatory Response in Goats Which Have Been Treated Repeatedly with Porcine Follicle-Stimulating Hormone ?
Remy, Benoit; Baril, Gérard; Vallet, J. C. et al

in Theriogenology (1991), 36(3), 389-99

Repeated administration of xenogenic gonadotropins in human or animal species may be responsible for antibody production and refractoriness. An experiment was conducted in which goats were treated with ... [more ▼]

Repeated administration of xenogenic gonadotropins in human or animal species may be responsible for antibody production and refractoriness. An experiment was conducted in which goats were treated with porcine FSH (p-FSH) at 6-week intervals for a period of 7 months. A sensitive radioimmunoassay (RIA) was used to detect antibodies to p-FSH in plasma samples taken at short-term intervals during a 7-month period. Antibodies appeared after the first injection, and levels increased following booster injections. A high correlation rate existed between antibody level and superovulatory response. Refractoriness in goats was associated with a high level of antibodies. [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 detailImmunocytochemical study of cell type distribution in the pituitary of Barbus barbus (Teleostei, Cyprindidae)
Toubeau, Gérard; Poilve, A.; Baras, Etienne et al

in General and Comparative Endocrinology (1991), 83(1), 35-47

Antisera to mammalian pituitary and placental hormones have been used to identify and localize the different cell types in the pituitary of the barbel (Barbus barbus, L.). The immunocytochemical labeling ... [more ▼]

Antisera to mammalian pituitary and placental hormones have been used to identify and localize the different cell types in the pituitary of the barbel (Barbus barbus, L.). The immunocytochemical labeling employed the immunoperoxidase technique or the immunogold silver staining procedure. Corticotrophic and prolactin cells, visualized using antisera to human adrenocorticotropic hormone and ovine prolactin (PRL), respectively, occur in the rostral pars distalis (RPD). Antisera against mammalian gonadotropins [ovine folliclestimulating hormone (FSH); bovine luteinizing hormone] or porcine growth hormone selectively cross-react with two different cell populations occupying the major part of the proximal pars distalis (PPD). Thyrotropic cells, stained by an antiserum to whole human thyroidstimulating hormone preabsorbed with porcine FSH, are scattered throughout the PPD and found amongst growth hormone and gonadotrophic cells. The majority of pars intermedia cells are stained with anti-melanophore stimulating hormone whereas the scattered PAS positive cells are revealed by both anti-ovine PRL and anti-bovine placental lactogen (or chorionic somatomammotropin). The latter antiserum also cross-reacts with the PRL cells of the RPD. Our results indicate that the distribution of the different cell types in Barbus barbus is similar to that described in other families of teleosts. This report is also the first demonstration of antigenic similarity between mammalian placental lactogen and fish prolactin. [less ▲]

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