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See detailAPRIL 1993 ARCTIC PROFILES OF STRATOSPHERIC HCL, CLONO2, AND CCL2F2 FROM ATMOSPHERIC TRACE MOLECULE SPECTROSCOPY ATLAS 2 INFRARED SOLAR OCCULTATION SPECTRA
Rinsland, C. P.; Gunson, M. R.; Abrams, M. C. et al

in Journal of Geophysical Research (1995), 100(D7), 14019-14027

Partitioning among the major components of the stratospheric odd chlorine family inside and outside of the remanent Arctic vortex has been studied on the basis of infrared solar occultation measurements ... [more ▼]

Partitioning among the major components of the stratospheric odd chlorine family inside and outside of the remanent Arctic vortex has been studied on the basis of infrared solar occultation measurements obtained by the atmospheric trace molecule spectroscopy (ATMOS) Fourier transform spectrometer during the ATLAS 2 shuttle mission (April 8-17, 1993). Profiles of hydrogen chloride (HCl) and simultaneous profiles of chlorine nitrate (ClONO2) and CFC-12 (CCl2F2) are reported for examples of in-vortex and out-of-vortex conditions. Increased ClONO2 volume-mixing ratios (VMRs) are measured in the vortex below 20 mbar (similar to 25 km altitude) with a peak ClONO2 VMR of 2.05 +/- 0.45 ppbv (10(-9) per volume) at 56 mbar (similar to 19 km altitude). The reported error correspond to la uncertainties. Simultaneous CCl2F2 and N2O measurements, combined with published empirical relations, indicate that only 0.34 +/- 0.15 ppbv, about 10% of total chlorine, was bound in organic species at the ClONO2 VMR peak in the vortex. A colocated vortex profile of HCl, referenced to simultaneous N2O VMR measurements, has been used to derive a HCl mixing ratio of 1.21 +/- 0.12 ppbv corresponding to the ClONO2 VMR peak. The internal consistency of the ATMOS measurements is demonstrated by the agreement between the total chlorine mixing ratio of 3.60 +/- 0.72 ppbv derived at the ClONO2 VMR peak in the vortex and HCl measurements of 3.37 +/- 0.37 and 3.76 +/- 0.41 ppbv at 0.56 mbar, where HCl is the only significant chlorine-bearing molecule. Outside the vortex the mixing ratio of HCl exceeds the mixing ratio of ClONO2 throughout the stratosphere. [less ▲]

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See detailStereocomplexation and morphology of polylactides
Brochu, Sylvie; Prud'homme, Robert E; Barakat, Ibrahim et al

in Macromolecules (1995), 28(15), 5230-5239

Blends of isotactic polylactides of opposite configurations lead to the formation of stereocomplexes, provided the enantiomeric excess of the two homopolymers in contact is high enough. In this study, the ... [more ▼]

Blends of isotactic polylactides of opposite configurations lead to the formation of stereocomplexes, provided the enantiomeric excess of the two homopolymers in contact is high enough. In this study, the stereocomplex formation between a poly(L-lactide) (100L) having an enantiomeric excess of 100% and a poly(D-lactide) having an enantiomeric excess of 80% (80D) has been investigated using differential scanning calorimetry and optical microscopy. These results have been compared to those obtained between two polylactides having both an enantiomeric excess of 100% (100L/100D blend). The melting temperatures of blends 100L/100D and 100L/80D are 230 and 208 degrees C, respectively. In both cases, the stereocomplex formation is preferred to the homopolymer crystallization and the stereocomplex controls the morphology of the blends over a wide range of concentrations. However, this control is more rigorous when the D component is 100% isotactic. This difference leads to a more complete crystallization of homopolymer 100L and to a greater influence of crystallization conditions in 100L/80D blends in comparison with 100L/100D blends. An epitaxial crystallization between the homopolymer 100L and the stereocomplex 100L/80D has also been observed at certain compositions. [less ▲]

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See detailBlends of biphasic ionomers with chemically identical mono- and bifunctional oligomers
Plante, Michel; Bazuin, C Géraldine; Jérôme, Robert ULg

in Macromolecules (1995), 28(15), 5240-5247

Biphasic Cs and Ba carboxylated polystyrene ionomers were blended with chemically identical mono- and bifunctional oligomers whose chain lengths are significantly greater than the average segmental length ... [more ▼]

Biphasic Cs and Ba carboxylated polystyrene ionomers were blended with chemically identical mono- and bifunctional oligomers whose chain lengths are significantly greater than the average segmental length between ionic groups in the ionomer. The ionomers were chosen to have two ion contents such that, in one case, the matrix phase is dominant and, in the other, the cluster phase is dominant. From dynamic mechanical thermal analysis, it was observed that the biphasic morphology of the ionomers is preserved in all blends (containing up to 60 wt % oligomer). The monofunctional oligomers tend to have a mild plasticizing action on the two phases. In the matrix-dominated ionomer, the bifunctional oligomer has an antiplasticization effect at lower oligomer contents; this is attributed to a greater dispersion of ionic aggregates in the matrix phase, accompanied by pinning of the oligomer extremities in multiplets, which prevents plasticizing action. In the cluster-dominated ionomer, the oligomer forms a separate phase, which is related to insufficiently large ion-poor styrene regions in the ionomer to accommodate the long nonionic portion of the oligomer chains. [less ▲]

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See detailLatent Bovine Herpesvirus 1 Infection in Calves Protected by Colostral Immunity
Lemaire, Mylène; Meyer, Gilles; Ernst, E. et al

in Veterinary Record : Journal of the British Veterinary Association (1995), 137(3), 70-1

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See detailControl of living anionic polymerization of (meth)acrylates : active complex species, macromolecular engineering and possible scaling-up
Teyssié, Philippe; Bayard, Philippe; Jérôme, Robert ULg et al

in Macromolecular Symposia (1995), 98

Tailored polymerization of acrylic and methacrylic esters, particularly methyl methacrylate (MMA), has been the topic of a frantic research effort during the last decade. It is the purpose of this paper ... [more ▼]

Tailored polymerization of acrylic and methacrylic esters, particularly methyl methacrylate (MMA), has been the topic of a frantic research effort during the last decade. It is the purpose of this paper to present one of the main lines of that quest, and to evaluate its potential versus other new approaches. [less ▲]

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See detailPolylactide microparticles prepared by double emulsion-evaporation 2 : Effect of the poly(lactide-co-glycolide) composition on the stability of the primary and secondary emulsions
Nihant, Nicole; Schugens, Chantal; Grandfils, Christian ULg et al

in Journal of Colloid and Interface Science (1995), 173(1), 55-65

Polylactide and copolymers with glycolide have been used as coating polymers in the microencapsulation technique based on the W1/o/w2 double emulsion-evaporation method. Stability of the primary emulsion ... [more ▼]

Polylactide and copolymers with glycolide have been used as coating polymers in the microencapsulation technique based on the W1/o/w2 double emulsion-evaporation method. Stability of the primary emulsion is of critical importance and clearly predetermines the internal morphology of the microspheres, in agreement with the very fast hardening of the oil phase (CH2Cl2) as soon as the primary emulsion is dispersed in water. When the peptide or' protein to be encapsulated is able to interact with the coating polymer and possibly with the surfactant, the stabilization mechanism of the primary emulsion is very complex. It has been shown that the interaction of BSA (bovine serum albumin) with the polyester is as strong as the glycolide content is high, which results in the formation of a solid film at the w1/o interface and in a high emulsion stability. Addition of a surfactant, such as poloxamer 188, in the oil phase has a deleterious effect on both the emulsion stability and the internal structure of the microspheres. Use of a dye tracer in the internal aqueous phase was not useful in probing the double emulsion stability and the encapsulation efficiency, because of specific interactions between the dye (indigocarmine) and the coating polyester. [less ▲]

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See detailHeterogeneity of sponastrime dysplasia: Delineation of a variant form with severe mental retardation
Verloes, Alain ULg; Misson, Jean-Paul ULg; Dubru, J. M. et al

in Clinical Dysmorphology (1995), 4(3), 208-215

We report a child with short stature, osteopenia with metaphyseal striations and severe mental retardation. This child shows radiological and clinical features of SPONASTRIME dysplasia. Only three ... [more ▼]

We report a child with short stature, osteopenia with metaphyseal striations and severe mental retardation. This child shows radiological and clinical features of SPONASTRIME dysplasia. Only three sibships with this disorder have been reported. In two families, affected patients were of normal intelligence. In the third one, as well as our case, the dysplasia was complicated by severe mental retardation of unknown origin. The severity of the retardation in our case and a previous report, and some difference in the gestalt and radiological aspects, suggest that SPONASTRIME dysplasia is a heterogeneous disorder. We provisionally propose to split SPONASTRIME dysplasia in two phenotypically distinct subgroups, and to delineate here a 'new' variant with microcephaly and severe mental impairment. [less ▲]

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See detailThe gene encoding bovine pregnancy-associated glycoprotein-1, an inactive member of the aspartic proteinase family
Xie, S.; Green, J.; Beckers, Jean-François ULg et al

in Gene (1995), 159(2), 193-197

Bovine pregnancy-associated glycoprotein 1 (bPAG1) is a member of the aspartic proteinase family. It becomes detectable in maternal serum soon after implantation and is produced specifically in the ... [more ▼]

Bovine pregnancy-associated glycoprotein 1 (bPAG1) is a member of the aspartic proteinase family. It becomes detectable in maternal serum soon after implantation and is produced specifically in the invasive binucleate cells of the placenta. As a result of a key mutation within its catalytic center, bPAG1 appears to be proteolytically inactive. Its gene consists of nine exons (size range 99-281 bp) and eight introns (87-1800 bp) organized in a manner very similar to those of proteolytically active mammalian aspartic proteinases. The transcription start point (tsp) is located 53 or 54 bp upstream from the start codon (ATG) and 19 bp downstream from a 5'-TATATAA sequence. Southern blot analyses have indicated the presence of two bPAG1 genes. By screening with an antiserum raised against bPAG1, a less common cDNA with 91% sequence identity to the bPAG1 transcript has been isolated from a placental cDNA library and presumably represents the second gene. At least eight other genes with sequences that hybridize relatively weakly to the bPAG1 probe are present in the bovine genome. Despite the similarities in the transcribed portion of the genes encoding PAG1, pepsinogen and other mammalian aspartic proteinases, the sequences upstream from the tsp of bPAG1 are unique. [less ▲]

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See detailElectrical conductivity in carbon black-loaded polystyrene-polyisoprene blends. Selective localization of carbon black at the interface
Soares, Bluma G; Gubbels, Frédéric; Jérôme, Robert ULg et al

in Polymer Bulletin (1995), 35(1-2), 223-228

The electrical conductivity of carbon-black loaded polystyrene-polyisoprene blends has been studied. In this ternary system, the filler is at the interface of co-continuous polyblends as confirmed by the ... [more ▼]

The electrical conductivity of carbon-black loaded polystyrene-polyisoprene blends has been studied. In this ternary system, the filler is at the interface of co-continuous polyblends as confirmed by the very low value of the filler percolation threshold (0.2 vol % for blends compression molded at 250 degrees C) and by optical microscopy. As a result of the selective localization of carbon black at the interface, the percolation threshold is very sensitive to the compression molding temperature. [less ▲]

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See detailA propos de la personnalité...
Garcet, Serge ULg

in Thérapies comportementales (1995), Volume XI- n°2

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See detailFractionation and partial characterization of proteins extracted from the bovine fallopian tube: preparation of tools for further purifications
Remy, Benoît ULg; Rabahi, F.; Duwez, L. et al

in Theriogenology (1995), 44(1), 95-107

Described in the present paper is a combined biochemical and immunological approach to study oviductal proteins in the bovine. Antisera were raised against semi-purified proteins extracted from bovine ... [more ▼]

Described in the present paper is a combined biochemical and immunological approach to study oviductal proteins in the bovine. Antisera were raised against semi-purified proteins extracted from bovine tubal mucosal tissue and were characterized. These antisera are available to monitor puritications of specific oviductal proteins in the future. Oviducts from 170 cyclic cows were collected at a slaughterhouse, and high amounts of mucosal proteins were extracted. The proteins were fractionated after precipitation with ammonium sulfate, anti-bovine serum albumin (bSA) and anti-bovine immunoglobulins bIg) afiinity chromatography and ion exchange chromatography. Each of the 12 fractions obtained after ion exchange chromatography was used to immunize a rabbit. Conditioned media were recovered from bovine oviduct cell monolayers cultured without serum to cot&m the oviductal origin of the extracted proteins. After Western blot analysis, 15 proteins were detected in the bovine oviductal extracts, and their molecular weights and isoelectric points were determined by 2 dimensional electrophoresis. Among these 15 proteins, 11 were also detected in conditioned media of bovine oviductal cells. These results demonstrate an oviductal origin of the 11 detected proteins and strongly suggest their secretion by the oviductal cells. [less ▲]

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See detailL'endocardite infectieuse. Concepts actuels
LANCELLOTTI, Patrizio ULg; Pierard, Luc ULg

in Revue Médicale de Liège (1995), 50(7), 281-5

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See detailEffects of fetal bovine serum, FSH and 17ß-Estradiol on the culture of bovine preantral follicles
Hulshof, S. C. J.; Figueiredo, J. R.; Beckers, Jean-François ULg et al

in Theriogenology (1995), 44(2), 217-226

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH ... [more ▼]

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH and 17beta-estradiol on the morphology and growth of the preantral follicles was investigated in medium without FBS. After culture in medium with 10% FBS, the increase in follicle diameter was 13.1 +/- 8.4 microm, the percentage of BrdU-labeled cells was 49.9 +/- 11.3 and the number of cells per area granulosa was 11.1 +/- 1.8. Omission of serum from the culture medium had no effect on the percentage of labeled cells, but the diameter increase was lower and the cells were smaller. Apparently, serum affects the size of the granulosa cells from small preantral follicles rather than the stimulation of cell proliferation. Addition of human recombinant FSH and/or 17beta-estradiol to serum-free medium resulted in a larger diameter increase during culture compared with that of the control. With FSH, this was due to an increase in cell proliferation, while with estradiol this was caused by an increase in granulosa cell size. The effects of simultaneous treatment with FSH and estradiol was simply the combination of their individual effects. In conclusion, small bovine preantral follicles can be cultured for 7 d in the absence of serum and hormones. The follicles increase in diameter and react to FSH with enhanced cell proliferation and to estradiol with an increase in cell size. [less ▲]

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See detailAnalysis of Bovine Herpesvirus 4 Genomic Regions Located Outside the Conserved Gammaherpesvirus Gene Blocks
Lomonte, P.; Bublot, M.; van Santen, V. et al

in Journal of General Virology (The) (1995), 76((Pt 7)), 1835-41

Bovine herpesvirus 4 (BHV-4) DNA sequences located outside the gene blocks conserved among the gammaherpesviruses BHV-4, herpesvirus saimiri (HVS) and Epstein-Barr virus (EBV) were analysed. Twelve ... [more ▼]

Bovine herpesvirus 4 (BHV-4) DNA sequences located outside the gene blocks conserved among the gammaherpesviruses BHV-4, herpesvirus saimiri (HVS) and Epstein-Barr virus (EBV) were analysed. Twelve potential open reading frames (ORFs) were found. Protein database comparisons showed that no ORF translation products were similar to proteins encoded by alpha- or betaherpesviruses. Nevertheless, six of the ORFs were homologous in amino acid sequences to proteins encoded by HVS but apparently not to those encoded by EBV. Furthermore, the location and orientation of these six ORFs in the BHV-4 genome were similar to the corresponding ORFs in the HVS genome. No genes homologous to known cellular genes were found in the BHV-4 genome; this feature is the major difference between the BHV-4 and HVS genomes with regards to the overall gene content. [less ▲]

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See detailTwo-wavelength holographic interferometry for the measurement of large deformations
Ninane, Nathalie ULg; Georges, Marc ULg

in SPIE's International Technical Working Group Newsletter : Holography (1995), 5(2), 5

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See detailDiaspirin Crosslinked Hemoglobin (Dclhb): Absence of Increased Free Radical Generation Following Administration in a Rabbit Model of Renal Ischemia and Reperfusion
Pincemail, Joël ULg; Detry, Olivier ULg; Philippart, C. et al

in Free Radical Biology & Medicine (1995), 19(1), 1-9

In control rabbits, a renal ischemia of 60 min followed by 10 min of reperfusion resulted in an enhanced free radical production in cortical tissue, as assessed by a significant decrease of free ... [more ▼]

In control rabbits, a renal ischemia of 60 min followed by 10 min of reperfusion resulted in an enhanced free radical production in cortical tissue, as assessed by a significant decrease of free glutathione (42%), protein-bound GSH (17%), and vitamin E (49%). In contrast, catalase or glutathione peroxidase activities were not affected by these experimental conditions. Free radical production in this model was also measured directly using electron spin resonance (ESR) spectroscopy associated with a PBN (alpha-phenyl N-tert-butyl-nitrone) spin trap agent in the venous blood arising from the ischemic kidney. The signal consisted of a triplet of doublets. In contrast, no signal could be detected in control blood samples taken prior to inducing ischemia. The burst of free radical production occurred in the early phase after restoration of flow in the kidneys rendered ischemic, as evidenced by a signal of weak intensity which generally appeared within the third minute after reperfusion and progressively increased to form a well-defined asymmetric signal following 10 min of reperfusion. The precise nature of free radicals trapped by the PBN agent remains, however, to be elucidated, but analysis of the coupling constants (aN = 14.5-15 G; a beta H = 2.5-3 G) and asymmetry of the central doublets suggests that the ESR signal may arise from a nitorxy-radical adduct resulting from the spin trapping by PBN of both oxygen- or carbon-centered radicals of lipid origin. As evidenced by both direct and indirect measurements, exchange of rabbit blood immediately after inducing renal ischemia with 30 ml/kg of Diaspirin Crosslinked Hemoglobin (7.5 g/dl in lactated electrolyte) or human serum albumin (7.5 g/dl in lactated electrolyte) did not exacerbate free radical production mediated by an ischemia reperfusion phenomenon, a typical situation found in a resuscitation setting. [less ▲]

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See detailNuclear Lesions During Rat Hepatocarcinogenesis. I. Measuring the Sister-Chromatid Exchanges During Initiation, Promotion and Progression of Rat Hepatocarcinogenesis Induced with Diethylnitrosamine
Herens, Christian ULg; Jacquemart, M.; Koulischer, Lucien ULg et al

in Mutation Research : Fundamental & Molecular Mechanisms of Mutagenesis (1995), 329(2), 153-9

Cytogenetic endpoints such as sister-chromatid exchanges (SCEs), chromosomal aberrations and micronuclei (MNs) have been widely used as indicators of genetic damage. However, no systematic attempts have ... [more ▼]

Cytogenetic endpoints such as sister-chromatid exchanges (SCEs), chromosomal aberrations and micronuclei (MNs) have been widely used as indicators of genetic damage. However, no systematic attempts have been made to correlate the levels of these cytogenetic endpoints with the different steps of carcinogenesis. In the present report, the induction, accumulation and persistence of SCEs and high frequency cells (HFCs) were measured in liver cells during the initiation, promotion and progression steps of rat hepatocarcinogenesis induced by diethylnitrosamine (DEN). The results indicate that lesions leading to SCEs accumulate during initiation only. When DEN administration is longer than the duration of this first step, SCE values stabilize. After stopping the carcinogenic treatment, the SCE levels decrease to control values whether or not promotion and progression occur. [less ▲]

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See detailSubstituent effect in anionic polymerization of β-lactones initiated by alkali metal alkoxides
Kurcok, Piotr; Matuszowicz, Andrzej; Jedlinski, Zbigniew et al

in Macromolecular Rapid Communications (1995), 16(7), 513-519

The influence of methyl substituent on the mechanism of the ring-opening polymerization of -lactones initiated by alkali metal alkoxides is discussed. Attention has been paid to the effect of the ... [more ▼]

The influence of methyl substituent on the mechanism of the ring-opening polymerization of -lactones initiated by alkali metal alkoxides is discussed. Attention has been paid to the effect of the substituent position in the monomer molecule on the ring-opening mechanism, the 3,3-dimethyl-2-oxetanone (pivalolactone), 4-methyl-2-oxetanone (beta-butyrolactone) and 2-oxetanone (beta-propiolactone) being chosen as model monomers. Moreover, it was found unexpectedly that in the case of pivalolactone polymerization, besides open-chain polymers, cyclic oligomers are produced. [less ▲]

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See detailEffect of Inducers and Pcbs on the Cytochrome P450 Enzymes in Cultured Quail Hepatocytes
Roelandt, L.; Dubois, Maryline; Todaro, Anna ULg et al

in Ecotoxicology & Environmental Safety (1995), 31(2), 158-63

Hepatocytes isolated from fetal quail livers (Coturnix coturnix japonica) were cultured in vitro. Their capacity to metabolize drugs and xenobiotics was explored with typical cytochrome P450 substrates ... [more ▼]

Hepatocytes isolated from fetal quail livers (Coturnix coturnix japonica) were cultured in vitro. Their capacity to metabolize drugs and xenobiotics was explored with typical cytochrome P450 substrates: ethoxycoumarin (known to be metabolized by several P450s), ethoxyresorufin (essentially dealkylated by P450IA1), and testosterone (specifically hydroxylated at several positions by several P450s). The cells could be kept metabolically active in culture for at least 4 days. Their drug-metabolizing activities were inducible by the usual P450 inducers, like phenobarbital and benzanthracene, but also by Aroclor 1254, a PCB mixture. The results obtained indicate that this experimental model could certainly be very helpful in ecotoxicological studies. [less ▲]

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See detailNuclear Lesions During Rat Hepatocarcinogenesis. II. Measuring the Micronuclei During Initiation, Promotion and Progression of Rat Hepatocarcinogenesis Induced with Diethylnitrosamine
Herens, Christian ULg; Massart, Sandrina ULg; Bouzahzah, B. et al

in Mutation Research : Fundamental & Molecular Mechanisms of Mutagenesis (1995), 329(2), 161-71

We reported in our companion paper the strong correlation between elevated sister-chromatid exchange (SCE) frequencies and the initiation step of rat hepatocarcinogenesis. We have also shown that SCEs ... [more ▼]

We reported in our companion paper the strong correlation between elevated sister-chromatid exchange (SCE) frequencies and the initiation step of rat hepatocarcinogenesis. We have also shown that SCEs return to normal values during the promotion and the progression stages. In the present study, we evaluated the clastogenic activity of diethylnitrosamine (DEN) during initiation, promotion and progression of rat hepatocarcinogenesis. We measured, at various times after DEN administration, the number of micronuclei (MN) produced by the mitotic response to partial hepatectomy. The results established that the DEN treatment induces a great number of preclastogenic lesions. In subcarcinogenic conditions (initiation alone), the number of MN expressed after partial hepatectomy remains high regardless of the time interval between the end of the DEN treatment and the operation. In this condition, the preclastogenic lesions persist for up to 1 year after the DEN administration is discontinued. Conversely, in carcinogenic conditions (initiation + promotion + progression), the number of MN expressed after partial hepatectomy decreases during the promotion and progression stages. These observations indicate that promotion and progression but not initiation are associated with the expression of persistent preclastogenic lesions, resulting in the production of chromosomally abnormal hepatocytes. [less ▲]

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See detailOrganisation spatiale et génération de mobilité
Hanocq, Philippe ULg

in Cahiers de l'Urbanisme (Les) (1995), 13-14

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See detailHydrogen Peroxide Hyperpolarizes Rat Ca1 Pyramidal Neurons by Inducing an Increase in Potassium Conductance
Seutin, Vincent ULg; Scuvée-Moreau, Jacqueline ULg; Massotte, Laurent ULg et al

in Brain Research (1995), 683(2), 275-8

It has been suggested that hydrogen peroxide is involved in cascades of pathological events affecting neural cells. The aim of this study was therefore to examine whether this molecule is able by itself ... [more ▼]

It has been suggested that hydrogen peroxide is involved in cascades of pathological events affecting neural cells. The aim of this study was therefore to examine whether this molecule is able by itself to modify membrane properties of pyramidal neurons in the CA1 region of the rat hippocampus. Intracellular recordings in the slice preparation showed that 3.3 mM hydrogen peroxide hyperpolarized all neurons tested (n = 41) by 11 +/- 3 mV. This effect persisted in the presence of tetrodotoxin. It developed slowly, was reversible and reproducible. In the presence of tetrodotoxin, the extrapolated reversal potential of this effect was -95 +/- 5 mV in 2.5 mM external potassium. This value was not significantly different from the one obtained with the GABAB agonist baclofen (10 microM) (-98 +/- 5 mV). It shifted when the concentration of external potassium was increased to 10.5 mM (from -96 +/- 5 to -62 +/- 4 mV), in close agreement with the Nernst equation potassium ions. The hyperpolarization was significantly reduced (by 65 +/- 22%) by the potassium channel blocker barium (100 microM). We suggest that hydrogen peroxide is able to induce an increase in potassium conductance in rat CA1 pyramidal neurons. The exact mechanism by which it produces this effect (direct action on channels or indirect effect) remains to be determined. [less ▲]

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See detailReconstitution of yeast nucelotide excision repair with purified RAD proteins, replication protein A and transcription factor TFIIH
Guzder, Sami; Habraken, Yvette ULg; Sung, Patrick et al

in Journal of Biological Chemistry (1995), 270(22), 12973-6

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See detailNomenclature stellaire et catalogues astronomiques - VIII.
Manfroid, Jean ULg; Renson, Pierre ULg

in Ciel (Le) (1995), 57

Not Available

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See detailClosantel Intoxication in a Dog
Mc Entee, Kathleen ULg; Grauwels, Magda ULg; Clercx, Cécile ULg et al

in Veterinary and Human Toxicology (1995), 37(3), 234-6

A case of overdosage with closantel, a salicynalide derivative, in a dog is described. The dog received 6 times the recommended dosage. Closantel induced optic neuritis, retinal degeneration, partial ... [more ▼]

A case of overdosage with closantel, a salicynalide derivative, in a dog is described. The dog received 6 times the recommended dosage. Closantel induced optic neuritis, retinal degeneration, partial deafness, hepatotoxicosis and myopathy. Only the blindness was irreversible. The therapy included albumin administration to reduce the acute toxicity of closantel. [less ▲]

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See detailSexual Differentiation of Brain and Behavior in Quail and Zebra Finches: Studies with a New Aromatase Inhibitor, R76713
Foidart, Agnès ULg; Balthazart, Jacques ULg

in Journal of Steroid Biochemistry & Molecular Biology (1995), 53(1-6), 267-75

In many species of vertebrates, major sex differences affect reproductive behavior and endocrinology. Most of these differences do not result from a direct genomic action but develop following early ... [more ▼]

In many species of vertebrates, major sex differences affect reproductive behavior and endocrinology. Most of these differences do not result from a direct genomic action but develop following early exposure to a sexually differentiated endocrine milieu. In rodents, the female reproductive phenotype mostly develops in the absence of early steroid influence and male differentiation is imposed by the early action of testosterone, acting at least in part through its central conversion into estrogens or aromatization. This pattern of differentiation does not seem to be applicable to avian species. In Japanese quail (Coturnix japonica), injection of estrogens into male embryos causes a permanent loss of the capacity to display male-type copulatory behavior when exposed to testosterone in adulthood. Based on this experimental result, it was proposed that the male reproductive phenotype is "neutral" in birds (i.e. develops in the absence of endocrine influence) and that endogenous estradiol secreted by the ovary of the female embryo is responsible for the physiological demasculinization of females. This model could be recently confirmed. Females indeed display a higher level of circulating estrogens that males during the second part of their embyronic life. In addition, treatment of female embryos with the potent aromatase inhibitor, R76713 or racemic vorozole which suppresses the endogenous secretion of estrogens maintains in females the capacity to display the full range of male copulatory behaviors. The brain mechanisms that control this sexually differentiated behavior have not been identified so far but recent data suggest that they should primarily concern a sub-population of aromatase-immunoreactive neurons located in the lateral parts of the sexually dimorphic preoptic nucleus. The zebra finch (Taeniopygia guttata) exhibits a more complex, still partly unexplained, differentiation pattern. In this species, early treatment with exogenous estrogens produces a masculinization of singing behavior in females and a demasculinization of copulatory behavior in males.(ABSTRACT TRUNCATED AT 400 WORDS) [less ▲]

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See detailPharma-clinics. Comment j'explore... une asthenie chronique
Moutschen, Michel ULg

in Revue Médicale de Liège (1995), 50(6), 268-9

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See detailDistribution of varicella-zoster virus gpI and gpII and corresponding genome sequences in the skin
Nikkels, Arjen ULg; Delvenne, Philippe ULg; Debrus, S. et al

in Journal of Medical Virology (1995), 46(2), 91-96

In the course of varicella-zoster virus (VZV) infection, some viral capsid antigens are found in the epidermis and dermis. The aim of this study was to investigate the localisation of two major VZV ... [more ▼]

In the course of varicella-zoster virus (VZV) infection, some viral capsid antigens are found in the epidermis and dermis. The aim of this study was to investigate the localisation of two major VZV glycoproteins (gpI and gpII) and of their respective genes in the skin. The distribution of VZV gpI and II in 27 formalin fixed paraffin embedded skin biopsies from herpes tester eruptions were compared by immunohistochemistry. Double immunostaining was carried our to identify infected cells. The presence of viral nucleic acids coding for gpI and gpII was examined by in situ hybridisation. The distribution of gpI and gpII and their corresponding genome sequences was similar in the epidermis, gpI and gpII were also detected in dermal FXIIIa positive dendrocytes, in Mac 387 and CD68 positive macrophages, and in perineural and endothelial cells. However, the corresponding viral nucleic acids were rarely and barely detected in these cells of the dermis. It is concluded that VZV infection of epithelial cells follows a different course than in dermal cells. (C) 1995 Wiley-Liss, Inc. [less ▲]

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See detailPrevention of Postmenopausal Bone Loss by Rectal Calcitonin
Reginster, Jean-Yves ULg; Jupsin, Isabelle ULg; Deroisy, Rita ULg et al

in Calcified Tissue International (1995), 56

A group (150) of healthy women, who had been menopausal for less than 5 years and who had never received any form of treatment to prevent bone loss were entered into a randomized, controlled study ... [more ▼]

A group (150) of healthy women, who had been menopausal for less than 5 years and who had never received any form of treatment to prevent bone loss were entered into a randomized, controlled study comprising three arms. They were randomly allocated to the double-blind administration of five suppositories per week containing either 100 IU of salmon calcitonin or a placebo, or to a group receiving a suppository containing 200 IU of salmon calcitonin three times per week. All women received 500 mg/day of calcium supplementation. After 12 months, bone mineral density (BMD) of the spine, measured by dual energy X-ray absorptiometry, decreased significantly (P < 0.01) in the placebo group by 3.1% (SD: 3.6%) but did not change in the two calcitonin groups [+1.3% (3.5%) with 100 IU/day and +2.3% (4.0%) with 200 IU 3/week]. The differences in response between the placebo group and the two calcitonin groups were significant (P < 0.05), but the difference between the two regimens of calcitonin administration was not. No differences appeared among the three groups for the response at the level of the hip. Evolution of biochemical markers reflecting bone turnover did not differ significantly among groups. Nearly 40% of the women withdrew prematurely because of local (rectal or intestinal) intolerance to repetitive suppositories, with a nonsignificantly different frequency in the placebo or calcitonin groups. We conclude that rectal calcitonin might be an interesting preventive approach against trabecular postmenopausal bone loss but that long-term acceptability of suppositories should be evaluated in view of each patient's sensibility or cultural background. [less ▲]

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See detailCopper whisker growth from inside sulfur-doped YBa2Cu307-X pellets
Cloots, Rudi ULg; Krekels, T.; Warin, R. et al

in Journal of Solid State Chemistry (1995), 117(1), 151-156

We report on the growth of Cu whiskers (10 mu m in linear transverse size) at the surface of a YBCO pellet, in a sulfur-rich atmosphere at a high synthesis temperature. Growth arises from inside the ... [more ▼]

We report on the growth of Cu whiskers (10 mu m in linear transverse size) at the surface of a YBCO pellet, in a sulfur-rich atmosphere at a high synthesis temperature. Growth arises from inside the pellet since there is no Cu in the surrounding atmosphere. We present the experimental conditions and electron microscopic observations. We briefly propose a mechanism based on chemical considerations, in particular, a Cu reductive nucleation of the CuS phase at the surface of YBCO. Natural phenomena, laboratory findings, and computer simulation work (based on an Eden model) support this interpretation. [less ▲]

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See detailCalcium et squelette: base physiologique d'une prévention
Reginster, Jean-Yves ULg

in Revue Médicale de Liège (1995), 50(6), 244-8

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See detailPerianal basal cell carcinoma
Kort, Rim; Fazaa, Becima; Bouden, Samira et al

in International Journal of Dermatology (1995), 34(6), 427-428

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See detailMétapsychologie de l'adolescence
Stassart, Martine ULg

in Cahiers du CEP (Centre d'Etudes Pathoanalytiques) (1995), 5(2), 71-104

Before 1960 there was very few psychoanalytical litterature about adolescence. Since 50 years, there is plenty of articles on that subject. The author comments the most important psychoanalytical writers ... [more ▼]

Before 1960 there was very few psychoanalytical litterature about adolescence. Since 50 years, there is plenty of articles on that subject. The author comments the most important psychoanalytical writers who brought a new and useful thought thereabout. [less ▲]

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See detailAppetitive as Well as Consummatory Aspects of Male Sexual Behavior in Quail Are Activated by Androgens and Estrogens
Balthazart, Jacques ULg; Reid, J.; Absil, Philippe ULg et al

in Behavioral Neuroscience (1995), 109(3), 485-501

Appetitive male sexual behavior was measured in male quail with the use of a learned social proximity procedure that quantified the time spent by a male in front of a window providing a view of a female ... [more ▼]

Appetitive male sexual behavior was measured in male quail with the use of a learned social proximity procedure that quantified the time spent by a male in front of a window providing a view of a female that was subsequently released into the cage, providing an opportunity for copulation. The learned response is not acquired by castrated males but can be acquired when castrates are treated with testosterone (T) or with the synthetic estrogen diethylstilbestrol or with the endogenous estrogen 17 beta-estradiol. Only birds that become sexually active acquire the response. Conversely, birds in which the consummatory copulatory behavior is disrupted by treatment with the antiestrogen tamoxifen lose the anticipatory response. These results demonstrate that appetitive sexual behavior is, like copulation, activated by T and by estrogens. This suggests that intracerebral aromatization of T also plays a critical role in the activation of this behavior. [less ▲]

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See detailGuidelines for Trials of Drug Treatments in Tension-Type Headache. First Edition: International Headache Society Committee on Clinical Trials
Schoenen, Jean ULg

in Cephalalgia : An International Journal of Headache (1995), 15(3), 165-79

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See detailLa maladie à virus Ebola, une fièvre hémorragique tropicale
Pierard, Gérald ULg

in Revue Médicale de Liège (1995), 50(6), 241-3

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See detailAromatase-Immunoreactive Cells Are Present in Mouse Brain Areas That Are Known to Express High Levels of Aromatase Activity
Foidart, Agnès ULg; Harada, N.; Balthazart, Jacques ULg

in Cell & Tissue Research (1995), 280(3), 561-74

The transformation of testosterone into estradiol in the brain plays a key role in several behavioral and physiological processes, but it has been so far impossible to localize precisely the cells of the ... [more ▼]

The transformation of testosterone into estradiol in the brain plays a key role in several behavioral and physiological processes, but it has been so far impossible to localize precisely the cells of the mammalian brain containing the relevant enzyme, viz., aromatase. We have recently established an immunohistochemical technique that allows the visualization of aromatase-immunoreactive cells in the quail brain. In this species, a marked increase in the optical density of aromatase-immunoreactive cells is observed in subjects that have been treated with the aromatase inhibitor, R76713 or racemic Vorozole. This increased immunoreactivity, associated with a total blockade of aromatase activity, has been used as a tool in the present study in which the distribution of aromatase-immunoreactive material has been reassessed in the brain of mice pretreated with R76713. As expected, the aromatase inhibitor increases the density of the immunoreactive signal in mice. Strongly immunoreactive cells are found in the lateral septal region, the bed nucleus of the stria terminalis, the central amygdala, and the dorso-lateral hypothalamus. A less dense signal is also present in the medial preoptic area, the nucleus accumbens, several hypothalamic nuclei (e.g., paraventricular and ventromedial nuclei), all divisions of the amygdala, and several regions of the cortex, especially the cortex piriformis. These data demonstrate that, contrary to previous claims, aromatase-immunoreactive cells are present in all brain regions that have been shown previously to contain high aromatase activity. [less ▲]

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See detailOxygen transfert during Bacillus subtilis fermentation. Influence of lipopeptide production, and an oxygen vector
Hbid, C.; Jacques, P.; Meurice, E. et al

in Archives of Physiology & Biochemistry (1995), 103

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See detailMicrodynamics of reverse micelles of ω- and α,ω-metal sulfonato polystyrene in toluene
Vanhoorne, Pierre ULg; Grandjean, Jean ULg; Jérôme, Robert ULg

in Macromolecules (1995), 28(10), 3553-3561

Reverse micelles of omega- and alpha,omega-metal sulfonato polystyrenes in toluene have been investigated by Li-6, Li-7, and pulsed field gradient NMR. Micelles are found to be of a narrow size ... [more ▼]

Reverse micelles of omega- and alpha,omega-metal sulfonato polystyrenes in toluene have been investigated by Li-6, Li-7, and pulsed field gradient NMR. Micelles are found to be of a narrow size distribution and to consist of roughly spherical ionic cores shielded from the solvent by a polystyrene shell. The nature of the ion pair is found to influence significantly the micellar size. The correlation time characteristic of lithium relaxation is faster than the reorientational correlation time of the aggregates, which means that lithium relaxation essentially takes place within the ionic cores. The effective relaxation mechanism is consistent with a fast exchange of lithium ions between different coordination sites within the aggregates. In concentrated solutions, the equilibrium between aggregated polymer chains and unassociated chains is essentially shifted toward the aggregated species. This tendency is reversed upon dilution. Below a critical micellar concentration of ca. 0.01 g/dL, only ''free'' chains persist in solution. Temperature has no significant effect on the position of the aggregation equilibrium. The aggregates are dissociated by the addition of a polar cosolvent, such as methanol, which solvates the ion pairs. The MeOH/Li+ molar ratio must, however, be higher than 100 to perturb significantly the ion pair aggregation. Up to a MeOH/Li+ ratio of 10 000, part of the chains remain aggregated, and the lithium spin-lattice relaxation is dominated by the aggregates. Above a MeOH/Li+ ratio of 10 000, the aggregates are almost completely disrupted. Self-diffusion coefficients of the difunctional chains are not dramatically smaller compared to the monofunctional counterparts, even when solutions of difunctional compounds form a gel. This behavior might be explained by the percolation model applied to the aggregation process, with the pulsed field NMR experiment probing only the selfdiffusion of the clusters in the sol phase of the gel. [less ▲]

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See detailHeavy elements in halo stars: the r/s-process controversy.
Magain, Pierre ULg

in Astronomy and Astrophysics (1995), 297

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis ... [more ▼]

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis are reviewed and rediscussed and it is shown that there is, in fact, no secure observational evidence in support of Truran's suggestion. A method to determine the odd-to-even isotopic ratio of barium, and thus to estimate the relative contributions of the r and s-processes, is presented. It takes advantage of the hyperfine structure affecting the spectral lines of the odd isotopes to distinguish them from the even isotopes. This method, applied to the classical metal-poor subgiant HD 140283, shows that the barium isotopic ratio in that star is in agreement with a pure s-process production, and excludes any significant enhancement of the r-process contribution, in disagreement with previous works based on elemental abundances. [less ▲]

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See detailCritical Re-Examination of the Distribution of Aromatase-Immunoreactive Cells in the Quail Forebrain Using Antibodies Raised against Human Placental Aromatase and against the Recombinant Quail, Mouse or Human Enzyme
Foidart, Agnès ULg; Reid, J.; Absil, Philippe ULg et al

in Journal of Chemical Neuroanatomy (1995), 8(4), 267-82

Mouse and quail aromatase cDNAs were isolated from libraries of mouse ovary and quail brain by using a human aromatase cDNA fragment (hA-24) as a probe. These three cDNAs were inserted into plasmid ... [more ▼]

Mouse and quail aromatase cDNAs were isolated from libraries of mouse ovary and quail brain by using a human aromatase cDNA fragment (hA-24) as a probe. These three cDNAs were inserted into plasmid vectors and expressed in Escherichia coli. Antisera against these purified recombinant proteins were raised in rabbit and purified by ammonium sulfate fractionation and affinity chromatography. The three antibodies directed against recombinant human, mouse and quail proteins were used to visualize aromatase-immunoreactive cells in the quail brain. They were compared with the antibody raised against human placental aromatase used in previous experiments and with another antibody recently developed by similar methods. The signal obtained with all antibodies was completely abolished by preadsorption with the homologous recombinant antigens and the signal produced by the two antibodies raised against placental aromatase was similarly abolished by a preadsorption with recombinant quail aromatase. The antibodies raised against recombinant proteins identified the major groups of aromatase cells previously described in the quail brain. The antibodies directed against the mouse and quail antigen identified more positive cells and stained them more densely than the antibodies raised against human recombinant antigen or purified placental aromatase. The new cell groups identified by the antibody raised against quail recombinant aromatase were located in an area ventral to the fasciculus prosencephali lateralis, the nucleus accumbens, the paleostriatum ventrale, the nucleus taeniae, the area around the nucleus ovoidalis, the caudal tuber and the mesencephalic central gray. A critical re-examination of the distribution and nomenclature of the aromatase-positive cells is proposed based on these new findings. [less ▲]

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See detailIsolement et caractérisation partielle d'une glycoprotéine associée à la gestation chez la brebis
Zoli, A. P.; Beckers, Jean-François ULg; Ectors, Francis ULg

in Annales de Médecine Vétérinaire (1995), 139

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See detailEXAFS study of halato-telechelic polymers and-capped with group IVb metal carboxylates at room and low temperature
Vlaic, G.; Navarra, G.; Regnard, J. R. et al

in Journal of Physics II France (1995), 5(5), 665-675

The EXAFS analysis at 300, 70 and 5 K has shown that the thermal disorder is very low in a carboxylato telechelic polybutadiene neutralized with an increasing excess of Zr isopropoxide. Two types of Zr-O ... [more ▼]

The EXAFS analysis at 300, 70 and 5 K has shown that the thermal disorder is very low in a carboxylato telechelic polybutadiene neutralized with an increasing excess of Zr isopropoxide. Two types of Zr-O bonds in the first shell account for the experimental data. The Zr-O distances and number of oxygen neighbours in the two subshells are found to be independent of temperature in the investigated range. The proportion of Zr in the samples has no effect on the total number of oxygen atoms around Zr, in contrast to their relative distribution in the two subshells. The number of Zr atoms increases in the second shell with the total amount of this metal. Upon increasing degree of neutralization from 200 to 600%, the static disorder increases together with a strong reduction of the dynamic part of the Debye-Waller (DW) factor. At a high degree of neutralization (> 400%), the DW factor for the Zr-Zr bond is largely independent of temperature. These observations agree with formation of Zr polynuclear microdomains, the size and rigidity of which increase with the Zr content, in good agreement with the profound changes previously reported in the viscoelastic properties of these materials. [less ▲]

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See detailExploration du testicule cryptorchide non palpe
Waltregny, David ULg; de Leval, Jean ULg

in Acta Urologica Belgica (1995), 63(2), 69-76

Cryptorchidism affects approximately 1 in 150 boys. Non-palpable testes represent nearly 20% of all cases. If present, they are situated between the inferior renal pole and the external inguinal ring ... [more ▼]

Cryptorchidism affects approximately 1 in 150 boys. Non-palpable testes represent nearly 20% of all cases. If present, they are situated between the inferior renal pole and the external inguinal ring. Often at surgical exploration, however, a "nubbin" of testicular tissue is found at the end of blind ending spermatic vessels without demonstration of a recognizable testis; this finding is referred to as an absent testis. In other patients, no vascular or ductular (epididymis-vas deferens) or even testicular structure can be observed. This situation defines true testicular agenesis. Non-palpable testes have an increased risk of malignant transformation, infertility, associated inguinal hernia and congenital ductular abnormalities. Surgical treatment is often more complex and unsuccessful. Many imaging diagnostic methods to investigate patients with non-palpable testes (pneumoperitoneography, angiography, ultrasonography, CT scan and RMN) have been used so far but none of these has been uniformly accepted as the ideal investigative technique because they are unreliable and/or they involve a fair risk. Since Cortesi and associates first described in 1976 a case of abdominal testes identified by laparoscopy, this technique has gained increased acceptance by pediatric urologists and surgeons. Today, celioscopy plays a central role in the exploration of non-palpable cryptorchid testes. The authors try to establish an algorithm methodology for investigating non-palpable testes under the light of recently reported anatomical, pathological and surgical data. [less ▲]

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See detailArbres, ordres maximaux et formes quadratiques entières
Pays, Isabelle ULg

in London Mathematical Society, Lecture Notes Series 215 (1995)

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See detailShear thickening of halato-telechelic polymers in apolar solvents
Maus, Christian; Fayt, Roger; Jérôme, Robert ULg et al

in Polymer (1995), 36(10), 2083-2088

Short-length polymers selectively end-capped with a metal carboxylato group at both ends, i.e, metal carboxylato-telechelic polymers, exhibit an unusual shear-thickening behaviour in apolar solvents ... [more ▼]

Short-length polymers selectively end-capped with a metal carboxylato group at both ends, i.e, metal carboxylato-telechelic polymers, exhibit an unusual shear-thickening behaviour in apolar solvents, depending on the main experimental parameters that control the ion-pair association, such as metal cation, concentration and temperature. In contrast to the non-ionic precursors, metal carboxylato-telechelics are indeed responsible for a marked increase in the solution viscosity in a range of shear rates between 0.1 and 1000 s(-1). The shear-rate dependence of the solution viscosity has been analysed in a close relationship to metal counterion, polymer concentration, temperature and addition of polar compounds to the apolar solvent. As a rule, the dilatant behaviour depends strongly on the formation of polymer aggregates in relation to the mutual interactions of the ion pairs. A consensus is now emerging on the origin of the shear-thickening effect, which should be found in inter-aggregate associations rather than in a transition from intramolecular to intermolecular associations of the individual chains. [less ▲]

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See detailKarl Marx, Œuvres, IV, Politique I
Durand, Pascal ULg

in Avancées (1995)

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See detailTemps et Don. Le Présent des médias
Durand, Pascal ULg

in Recherches en Communication (1995), 3

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See detailLes plaisirs romanesques. Le roman au XVIIIe siècle en France et en Angleterre
Durand, Pascal ULg

in Loisirs-Magazine, revue sur cassette de la Ligue Braille (1995), (88),

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See detailActivité sportive et susceptibilité à l'infection
Bury, Thierry ULg

in Revue Médicale de Liège (1995), 50(5), 222-5

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See detailSpontaneous and Induced Apoptosis after Whole Body Radiation Exposure: Experimental Approaches. Observations in Radio-Induced Thymic Lymphomagenesis
Humblet, Chantal ULg; Deman, J.; Franzen, Rachelle ULg et al

in Stem Cells (1995), 13(Suppl 1), 129-35

Radio-induced thymic lymphomagenesis is associated with alterations in the balance between thymocyte subsets and cytokinetic perturbations. The objectives of this work were to investigate whether these ... [more ▼]

Radio-induced thymic lymphomagenesis is associated with alterations in the balance between thymocyte subsets and cytokinetic perturbations. The objectives of this work were to investigate whether these alterations are associated with alterations in the basic levels of thymocyte apoptosis. For this purpose, we tested DNA fragmentation by gel electrophoresis, analyzed DNA content by propidium iodide staining of ethanol fixed cells and looked for DNA strand breaks on tissue sections by in situ end labeling. We described an increase of the levels of apoptosis in cultured thymocytes during the preleukemic period, while the basic levels of apoptosis observed in situ are similar in normal and in preleukemic thymuses. We propose that after leukemogenic irradiations, there is an increase of cells wherein the cell suicide program is activated but that environmental thymic factors rescue them from apoptosis. Preleukemic cells could belong to this abnormally surviving population of cells "programmed to die," wherein additional genomic abnormalities would lead to fully neoplastic transformation. [less ▲]

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See detailElectrophysiologic evaluation of the phrenic nerve-diaphragm pathway in an intact conscious calf model
Desmecht, Daniel ULg; Linden, Annick ULg; Lekeux, Pierre ULg

in American Journal of Veterinary Research (1995), 56(5), 545-554

Owing to technical and ethical limitations, a substantial part of the knowledge about the pathophysiologic mechanism of the human diaphragm has been obtained from studies in which phrenic nerve activation ... [more ▼]

Owing to technical and ethical limitations, a substantial part of the knowledge about the pathophysiologic mechanism of the human diaphragm has been obtained from studies in which phrenic nerve activation was usually carried out by direct surgical exposure of the nerves in the neck of deeply anesthetized, mechanically ventilated animals. Novel information has been gleaned from such studies, but the restrictive conditions under which it was collected preclude reliable extrapolation. We, therefore, addressed the question of whether accurate electrophysiologic evaluation of the phrenic nerve-diaphragm pathway can be performed in intact, nonanesthetized calves. Transjugular phrenic activation was well tolerated, safe, specific, and able to achieve constant symmetric and supramaximal phrenic stimulations during prolonged periods. Eighteen noninvasive cutaneous and esophageal reception circuits were tested for their ability to record the diaphragmatic evoked potential. In addition, they were compared for specificity and reproducibility of the recorded potentials during prolonged periods of tidal or stimulated respiration. The best diaphragmatic potential was recorded from surface electrodes attached to the skin of the ninth and tenth intercostal spaces, using a xyphoidian reference. We describe a method that allows easy, longterm, and reliable electrophysiologic evaluation of the phrenic nerve-diaphragm pathway in intact, conscious calves. It is hoped that such a model will produce relevant novel information regarding pathophysiology of the diaphragm. [less ▲]

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See detailAn interactive activation model of face naming
Brédart, Serge ULg; Valentine, T.; Calder, A. et al

in Quarterly Journal of Experimental Psychology (1995), 48A(2), 466-486

Burton and Bruce's (1992) model of face naming predicts a "fan effect", in which naming of famous people about whom many descriptive properties are known should be slower than naming of celebrities about ... [more ▼]

Burton and Bruce's (1992) model of face naming predicts a "fan effect", in which naming of famous people about whom many descriptive properties are known should be slower than naming of celebrities about whom few properties are known. An experiment is reported that showed that, contrary to this prediction, knowledge of many descriptive properties facilitated face-naming latency. An alternative architecture for an interactive activation model is proposed in which descriptive properties are represented in separate pools of units for each domain of information and in which names are represented by a separate pool of lexical output units. Computer simulations showed that this model could simulate the previously available empirical data as effectively as Burton and Bruce's (1992) original model. However, the proposed model could also simulate the effect of the number of known descriptive properties upon face-naming latency observed in the experiment reported. The new architecture also has the advantage of being more compatible with current models of speech production, and it allows preserved access to unique semantic properties in the context of impaired face naming as reported in the neuropsychological literature. [less ▲]

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See detailIntérêt de l'étude de l'expectoration induite en pathologie pulmonaire
Kayembe, J. M.; Louis, Renaud ULg; Bury, Thierry ULg et al

in Revue Médicale de Liège (1995), 50(5), 209-12

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See detailA Double-Blind, Placebo-Controlled, Dose-Finding Trial of Intermittent Nasal Salmon Calcitonin for Prevention of Postmenopausal Lumbar Spine Bone Loss
Reginster, Jean-Yves ULg; Deroisy, Rita ULg; Lecart, M. P. et al

in American Journal of Medicine (1995), 98(5), 452-8

PURPOSE: Nasal administration of salmon calcitonin (SCT) has been suggested for preventing trabecular bone loss during the first years following the menopause, but no conclusive evidence has appeared ... [more ▼]

PURPOSE: Nasal administration of salmon calcitonin (SCT) has been suggested for preventing trabecular bone loss during the first years following the menopause, but no conclusive evidence has appeared about the minimal effective dose. Since nasal calcitonin is highly expensive, it makes sense to define this dose. PATIENTS AND METHODS: We performed a double-blind, placebo-controlled, randomized, single-center study with a 3-arm parallel-group design. The subjects were 251 healthy women who had experienced natural menopause within the past 6 to 72 months and were not affected by any diseases or treatments that interfere with calcium metabolism. They were randomly allocated in groups of 6 to receive intranasal SCT 50 IU (n = 84), SCT 200 IU (n = 84), or placebo (n = 83). All treatments were given on 5 consecutive days per week. Statistical analysis was based on two populations: intention-to-treat (IT) and valid completers (VC). The main assessments performed were bone mineral density of the lumbar spine (LSBMD) and biochemical parameters reflecting bone turnover (serum alkaline phosphatase, urinary calcium/creatinine, and hydroxyproline/creatinine ratios). RESULTS: Changes over the treatment period were comparable in the IT and VC populations. In the group receiving the placebo, LSBMD decreased from baseline to end point by a mean of 6.28% (95% confidence interval [CI] -7.69 to -4.89) in the IT population and 6.98% (95% CI -8.86 to -5.11) in the VC population (P = 0.0001, end LSBMD versus baseline LSBMD). LSBMD increased slightly with the 50-IU/d dose of SCT, by 0.82% (95% CI -0.26 to 1.89) in the IT population, and 0.51% (95% CI -0.69 to 1.72) in the VC (P = NS, versus baseline). Subjects who received SCT 200 IU/d experienced significant increases of 2.03% (95% CI 0.92 to 3.15) in the IT population and 2.26% (95% CI 1.01 to 3.51) in the VC (both P = 0.001). The difference between the evolution of the combined groups receiving nasal SCT and the group treated with the placebo was highly significant (P = 0.0001). No significant changes were recorded in biochemical parameters reflecting bone turnover. CONCLUSIONS: SCT 50 IU/d administered nasally and intermittently appears to prevent lumbar bone loss in nonobese early postmenopausal women. [less ▲]

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See detailComment je traite... un patient avec une insuffisance cardiaque sévère ou aggravée
Pierard, Luc ULg

in Revue Médicale de Liège (1995), 50(5), 197-8

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See detailImmunogold Labelling of Fatty Acyl Chains
Compère, Philippe ULg; Maneta-Peyret, Lilly; Goffinet, Gerhard ULg et al

in Journal of Immunological Methods (1995), 181(2), 201-9

For the first time, antibodies against a hydrophobic hapten have been used for immunogold labelling of a lipid antigen (BSA-C18:1 conjugate) coated on polystyrene. The labelling was visualised either ... [more ▼]

For the first time, antibodies against a hydrophobic hapten have been used for immunogold labelling of a lipid antigen (BSA-C18:1 conjugate) coated on polystyrene. The labelling was visualised either directly in transmission electron microscopy or in light microscopy after silver enhancement. Good recognition of the fatty acyl chain was obtained even after treatment of the antigen coat with various cross-linking fixatives used for electron microscopy, i.e. formaldehyde, glutaraldehyde and osmium tetroxide. [less ▲]

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See detailMutational analysis of varicella-zoster virus major immediate-early protein IE62
Baudoux, Laurence; Defechereux, Patricia; Schoonbroodt, Sonia et al

in Nucleic Acids Research (1995), 23(8), 1341-1349

The varicella-zoster virus (VZV) open reading frame 62 encodes an immediate-early protein (IE62) that transactivates expression of various VZV promoters and autoregulates its own expression in transient ... [more ▼]

The varicella-zoster virus (VZV) open reading frame 62 encodes an immediate-early protein (IE62) that transactivates expression of various VZV promoters and autoregulates its own expression in transient expression assays. In Vero cells, IE62 was shown to transactivate the expression of all putative immediate-early (IE) and early (E) genes of VZV with an up-regulating effect at low intracellular concentrations. To define the functional domains involved in the regulatory properties of IE62, a large number of in-frame insertions and deletions were introduced into a plasmid-borne copy of the gene encoding IE62. Studies of the regulatory activities of the resultant mutant polypeptides in transient expression assays allowed to delineate protein regions important for repression of its own promoter and for transactivation of a VZV putative immediate-early gene (ORF61) promoter and an early gene (ORF29) promoter. This mutational analysis resulted in the identification of a new functional domain situated at the border between regions 4 and 5 which plays a crucial role in the IE62 regulatory functions. This domain turned out to be very well conserved amongst homologous alphaherpesvirus regulatory proteins and appeared to be rich in bulky hydrophobic and proline residues, similar to the proline-rich region of the CAAT box binding protein CTF-1. By immunofluorescence, a nuclear localization signal has been mapped in region 3. [less ▲]

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See detailGlobal compartmental analysis of the fluorescence decay surface of the halato telechelic polymer (N,N-dimethyl-N-[3-(1-pyrenyl)propyl]ammonio)-trifluoro-methanesulfonate-end-capped poly(tetrahydrofuran
Hermans, Bart; De Schryver, Frans C; Van Stam, Jan et al

in Macromolecules (1995), 28(9), 3380-3386

The kinetic behavior of the halato telechelic polymer (N,N-dimethyl-N-[3-(1-pyrenyl)propyl]-ammonio)trifluoromethanesulfonate-end-capped poly(tetrahydrofuran) (POLYPROBE) in tetrahydrofuran is ... [more ▼]

The kinetic behavior of the halato telechelic polymer (N,N-dimethyl-N-[3-(1-pyrenyl)propyl]-ammonio)trifluoromethanesulfonate-end-capped poly(tetrahydrofuran) (POLYPROBE) in tetrahydrofuran is investigated by global compartmental analysis of the fluorescence decay surface. At low POLYPROBE concentrations the emission decays monoexponentially. When an analogous end-capped halato telechelic polymer without the pyrene chromophore ((N,N,N-triethylammonio)trifluoromethanesulfonate-end-capped poly(tetrahydrofuran), POLYSALT) is added to solutions containing a low POLYPROBE concentration, the emission can be fitted by a biexponential decay function. From these observations it is concluded that the second excited-state species in the POLYPROBE-POLYSALT system is POLYPROBE involved in ion aggregation due to dipole-dipole or ion-dipole interaction. At higher POLYPROBE concentrations, without added POLYSALT, a triexponential decay function is needed to describe the emission. The third excited-state species is POLYPROBE excimer, which can be formed via two pathways: either intermolecularly when a locally excited POLYPROBE encounters a ground-state POLYPROBE or intramolecularly when an aggregate of two POLYPROBE molecules rearranges. From the global compartmental analysis in which the value of one of the rate constants is scanned, it is found that the bimolecular processes are slowed down by the presence of the polymer chain, while intramolecular rearrangements are not affected. [less ▲]

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See detailGalectin-1 Modulates Human Melanoma Cell Adhesion to Laminin
van den Brule, F. A.; Buicu, C.; Baldet, M. et al

in Biochemical and Biophysical Research Communications (1995), 209(2), 760-7

Galectins constitute a gene family of beta-galactoside-specific lectins that show high homology in their carbohydrate-binding site. They have been postulated to be involved in many biological events, but ... [more ▼]

Galectins constitute a gene family of beta-galactoside-specific lectins that show high homology in their carbohydrate-binding site. They have been postulated to be involved in many biological events, but their specific functions are not yet well defined. Galectin-1 is a laminin binding protein that recognizes poly-N-acetyllactosamine chains on this major basement membrane glycoprotein. In this study, we analyzed the possibility that galectin-1 could modulate interactions between human melanoma cells and laminin. We demonstrated that A375 and A2058 cell lines express galectin-1 both intracellularly and on the cell surface. In an in vitro assay, recombinant galectin-1 increased melanoma cell attachment to laminin in a dose-dependent manner. This effect was abolished by lactose. Anti-galectin-1 inhibited adhesion of melanoma cells to laminin in a dose-dependent fashion. However, neither galectin-1 nor anti-galectin-1 antibody affected melanoma cell spreading on laminin in vitro. These data indicate that galectin-1 might participate in melanoma cell adhesion to laminin and therefore could be a modulator of invasion and metastasis. [less ▲]

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See detailMolecular design of multicomponent polymer systems XIX : stability of cocontinuous phase morphologies in low-density polyethylene-polystyrene blends emulsified by block copolymers
Harrats, Charef; Blacher, Silvia ULg; Fayt, Roger et al

in Journal of Polymer Science. Part B, Polymer Physics (1995), 33(5), 801-811

Polyethylene-polystyrene blends containing small amounts of polyethylene (20 wt %) display a cocontinuous phase morphology that is very unstable in the absence of an emulsifier. The kinetics of ... [more ▼]

Polyethylene-polystyrene blends containing small amounts of polyethylene (20 wt %) display a cocontinuous phase morphology that is very unstable in the absence of an emulsifier. The kinetics of coalescence at high temperature is therefore very sensitive to differences in the interfacial activity of added polymeric emulsifiers. The morphology of blends added with a pure or a tapered hydrogenated polybutadiene-b-polystyrene block copolymer is investigated as a function of annealing time at 180°C. Various image treatments (standard granulometry, opening size granulometry distribution, and multiscaling analysis) were used to quantify the morphological evolution of these blends. The results clearly demonstrate that the tapered block copolymer is definitely more efficient than the corresponding pure diblock for stabilizing the cocontinuous structure of these blends. The differential behavior is assumed to results from differences in the tendency of the two copolymers to segregate and form their own domains. © 1995 John Wiley [less ▲]

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See detailEffects of Pcbs (Aroclor 1254) on Cytochrome-P450 Expression and Monooxygenase Activities in Cultured Foetal Rat Hepatocytes
Roelandt, L.; Todaro, Anna ULg; Thomé, Jean-Pierre ULg et al

in Toxicology (1995), 98(1-3), 95-103

Polychlorinated biphenyls (PCBs) are widespread residual micropollutants which accumulate in living organisms, probably as a consequence of their high lipophilicity. Cultured foetal rat hepatocytes used ... [more ▼]

Polychlorinated biphenyls (PCBs) are widespread residual micropollutants which accumulate in living organisms, probably as a consequence of their high lipophilicity. Cultured foetal rat hepatocytes used as target cells constitute an interesting in vitro model for studying the mechanisms of action of PCBs. In this paper, and the accompanying one (Toxicology 98 (1995) 83-94), we have used this model to investigate the effects of PCBs on several cellular parameters. The inducibility of CYPIA1 is the most sensitive parameter studied, as shown by the induction of ethoxycoumarin-O-deethylase and ethoxyresorufin-O-deethylase activities at PCB concentrations as low as 1 microM. Dexamethasone treatment of the cells potentiates this induction. PCB induction is reversible and occurs even in cells cultured for several days. CYP2B and CYP3A seem unaffected by PCBs in this experimental system. By inducing CYP1A1, PCBs can trigger the 'activation' of xenobiotics, such as polycyclic hydrocarbons, into mutagenic compounds. [less ▲]

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See detailCytotoxic Effects of Aroclor 1254 on Ultrastructure and Biochemical Parameters in Cultured Foetal Rat Hepatocytes
Thomé, Jean-Pierre ULg; Roelandt, L.; Goffinet, Gerhard ULg et al

in Toxicology (1995), 98(1-3), 83-94

The cytotoxicity of a commercial PCB mixture, Aroclor 1254, was assessed on cultured foetal rat hepatocytes. Under control conditions, dexamethasone stimulates immature hepatocytes to differentiate into ... [more ▼]

The cytotoxicity of a commercial PCB mixture, Aroclor 1254, was assessed on cultured foetal rat hepatocytes. Under control conditions, dexamethasone stimulates immature hepatocytes to differentiate into both hepatocytes and biliary epithelial cells. Consequently, foetal rat hepatocytes maintain, in vitro, a liver-like organization with spaces corresponding to the lumen of biliary canalicules, many mitochondria, and a well-developed rough endoplasmic reticulum (RER). This in vivo-like organization of cultured rat hepatocytes remains unchanged in medium supplemented with Aroclor 1254 at concentrations below 25 microM. In the 25-125 microM concentration range, however, PCBs severely alter some cellular organelles, notably causing important development of the RER and the appearance of cytoplasmic lacunae containing laminated concentric membrane arrays. In addition, the number of lipid droplets increases, the glycogen islets disappear, and dramatic local alterations of the mitochondrial cristae occur. In exposed and unexposed cells, the following biochemical parameters were measured: the DNA content, protein synthesis, lipid peroxidation, and urea formation. The results show that Aroclor 1254 at concentrations exceeding 25 microM (but not at lower concentrations) causes irreversible damage to cultured hepatocytes. The observed ultrastructural modifications are in good agreement with several in vivo studies on rat liver. Thus, isolated foetal rat hepatocytes have considerable potential as an alternative to whole animals for use in (eco)toxicological studies. [less ▲]

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See detailAuroral Lyman alpha and H2 bands from the giant planets. 2: Effect of the anisotropy of the precipitating particles on the interpretation of the 'color ratio'
Prange, Renee; Rego, Daniel; Gérard, Jean-Claude ULg

in Journal of Geophysical Research (1995), 100

Previous spectral analyses have given evidence of collisionally excited Jovian and (at times) Saturnian H2 Werner bands being absorbed by hydrocarbons at the shortest wavelengths along the auroral ovals ... [more ▼]

Previous spectral analyses have given evidence of collisionally excited Jovian and (at times) Saturnian H2 Werner bands being absorbed by hydrocarbons at the shortest wavelengths along the auroral ovals, and of a longitudinal dependence of this absorption in the Jovian aurorae. This 'color ratio' has been used to estimate the energy of the primary particles. In such estimates, particles are generally assumed to penetrate vertically into the atmosphere. However, the precipitating particle angular distribution is unknown, and a model developed for a diffuse aurora by Prange and Elkhamsi (1991), for instance, predicts quite different possible distributions. We consider here the influence of the angular distribution used in the model, and show that distributions peaking far from vertical may increase the energy derived from a given color ratio by as much as a factor of 3. We discuss previous interpretations of the color ratio longitudinal modulation (variation of the auroral atmosphere structure, or of the incident particle energy) in view of the subsequent increase in energy input. We argue that an interpretation in terms of energy variations only is not consistent with the energy available in the magnetosphere if the aurorae are diffuse, and we discuss this finding in the context of recent Hubble Space Telescope (HST) images. [less ▲]

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See detailLaparoscopic Removal of Pheochromocytoma. Why? When? And Who? (Reflections on One Case Report)
Meurisse, Michel ULg; Joris, Jean ULg; Hamoir, Etienne ULg et al

in Surgical Endoscopy (1995), 9(4), 431-6

Until now, the need for wide exposure and nonmanipulative dissection of pheochromocytoma has dictated the use of a large intraperitoneal transabdominal approach, which unfortunately results in a ... [more ▼]

Until now, the need for wide exposure and nonmanipulative dissection of pheochromocytoma has dictated the use of a large intraperitoneal transabdominal approach, which unfortunately results in a significant incidence of morbidity. A unilateral retroperitoneal approach guided by the refinements of new imaging techniques is less invasive but is associated with a small risk of incomplete cure. In one case report, we tested the hypothesis that laparoscopic surgery could combine the beneficial effects of both operative strategies without their respective side effects. We concluded that a laparoscopic approach combined with exclusive intraoperative infusion of nicardipine, a calcium-channel blocker, can be used to surgically remove pheochromocytoma under stable hemodynamic conditions. This provides better exposure of the anatomical structures than open surgery and allows a visual exploration of the entire abdominal cavity to exclude tumor multicentricity or ectopic sites in the case of inconclusive preoperative imaging investigations. Moreover, conversion to open surgery is always possible if needed. [less ▲]

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See detailSaturation of Penicillin-Binding Protein 1 by Beta-Lactam Antibiotics in Growing Cells of Bacillus Licheniformis
Lepage, Sylvie ULg; Lakaye, Bernard ULg; Galleni, Moreno ULg et al

in Molecular Microbiology (1995), 16(2), 365-72

With the help of a new highly sensitive method allowing the quantification of free penicillin-binding proteins (PBPs) and of an integrated mathematical model, the progressive saturation of PBP1 by various ... [more ▼]

With the help of a new highly sensitive method allowing the quantification of free penicillin-binding proteins (PBPs) and of an integrated mathematical model, the progressive saturation of PBP1 by various beta-lactam antibiotics in growing cells of Bacillus licheniformis was studied. Although the results confirmed PBP1 as a major lethal target for these compounds, they also underlined several weaknesses in our present understanding of this phenomenon. In growing cells, but not in resting cells, the penicillin target(s) appeared to be somewhat protected from the action of the inactivators. In vitro experiments indicated that amino acids, peptides and depsipeptides mimicking the peptide moiety of the nascent peptidoglycan significantly interfered with the acylation of PBP1 by the antibiotics. In addition, the level of PBP1 saturation at antibiotic concentrations corresponding to the minimum inhibitory concentrations was not constant, suggesting that additional, presently undiscovered, factors might be necessary to account for the experimental observations. [less ▲]

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See detailChanges in Bronchial Responsiveness, Circulating Leucocytes and Ex Vivo Cytokine Production by Blood Monocytes after Paf Inhalation in Allergic Asthmatics
Louis, Renaud ULg; Degroote, D.; Bury, Thierry ULg et al

in European Respiratory Journal (1995), 8(4), 611-8

We investigated the effects of inhaled platelet-activating factor (PAF) on methacholine bronchial responsiveness, circulating leucocyte counts, and ex vivo tumour necrosis factor alpha (TNF alpha) and ... [more ▼]

We investigated the effects of inhaled platelet-activating factor (PAF) on methacholine bronchial responsiveness, circulating leucocyte counts, and ex vivo tumour necrosis factor alpha (TNF alpha) and interleukin-1 (IL-1) production from blood monocytes in eight allergic asthmatics. Bronchial responsiveness was defined as the provocative concentration of methacholine causing a 20% decrease in forced expiratory volume in one second (PC20). Circulating leucocytes were counted by means of an automatic haemocytometer, and cytokines were measured with specific immunoassays. The different variables were measured before and 4, 24, 48, 72 and 168 h after a PAF (225 micrograms), a lyso-PAF (225 micrograms) and a saline bronchial challenge. When compared with lyso-PAF and saline, inhalation of PAF resulted in a significant decrease in PC20 over a period of one week. Two falls in bronchial responsiveness were identified, the first by 4 h and the second beginning 48 h and reaching a maximum by 168 h. The increases in spontaneous TNF alpha and IL-1 production which occurred during the week after both PAF, lyso-PAF and saline, did not differ significantly. Likewise, the changes in circulating neutrophil counts, characterized by a transient rise by 4 h after PAF and lyso-PAF but not saline, followed by a fall by 24 h and a persistent decrease until 168 h, were not significantly different after PAF, lyso-PAF and saline. On the other hand, in comparison with lyso-PAF and saline, inhaled PAF caused a significant protracted augmentation in circulating eosinophil counts, which was maximal by 48 h but did not correlate with the delayed decline in PC20.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailPrévenir l'herpès néonatal
Nikkels, Arjen ULg

in Virologics (1995), 5

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See detailDual analysis with general boundary conditions
Debongnie, Jean-François ULg; Zhong, H. G.; Beckers, Pierre ULg

in Computer Methods in Applied Mechanics & Engineering (1995), 122(1-2), 183-192

The dual analysis concept was introduced by Fraeijs de Veubeke [1] as a consequence of upper and lower bounds of the energy. As such bounds exist only in those cases where one type of condition is ... [more ▼]

The dual analysis concept was introduced by Fraeijs de Veubeke [1] as a consequence of upper and lower bounds of the energy. As such bounds exist only in those cases where one type of condition is homogeneous, it is commonly admitted that a dual error measure does not exist with general boundary conditions. This paper presents a re-examination of the dual error measure by a way which avoids any use of upper and lower bounds of the energy. It is found that such an error measure holds whatever the boundary conditions be. Furthermore, it is not necessary to obtain the approximate solutions by a Rayleigh-Ritz process, so that the second analysis, which seemed necessary in the original dual analysis concept, may be replaced by any admissible approximation. This implies the possibility of a dual error measure at a simple post-processor level. [less ▲]

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See detailRegulation of Histamine Release from Human Bronchoalveolar Lavage Mast Cells by Stem Cell Factor in Several Respiratory Diseases
Louis, Renaud ULg; Tilkin, P.; Poncelet, M. et al

in Allergy (1995), 50(4), 340-8

We investigated the effects of stem cell factor (SCF) on histamine release (HR) from human bronchoalveolar lavage (BAL) mast cells. BAL cells were recovered from lavage performed in patients undergoing ... [more ▼]

We investigated the effects of stem cell factor (SCF) on histamine release (HR) from human bronchoalveolar lavage (BAL) mast cells. BAL cells were recovered from lavage performed in patients undergoing clinical bronchoscopy. SCF (0.02-20 ng/ml), which is by itself a poor secretagogue (mean +/- SEM HR: 3.7 +/- 0.9%; n = 27), strongly enhanced HR induced by anti-IgE in a concentration-related manner. Significant potentiation began at 0.2 ng/ml (30 +/- 10%; p < 0.05; n = 12) and reached a plateau at 2 ng/ml (40 +/- 10%; P < 0.01 at 2 ng/ml and 45 +/- 10%; P < 0.01 at 20 ng/ml; n = 12). In contrast, SCF failed to enhance HR induced by calcium ionophore A23187. Among the BAL cell samples initially unresponsive to anti-IgE (55% of samples), 36% (10/28) were converted to responders if the cells were shortly preincubated with SCF. In 25% of samples (7/27), SCF (20 ng/ml) caused direct HR of 10 +/- 2.1%. The mast cells which released histamine when challenged with SCF also secreted higher levels of histamine in response to anti-IgE and calcium ionophore than those nonresponsive to SCF. While interleukin (IL)-3 and IL-5 (20 ng/ml) were unable to modulate immunologic HR, GM-CSF (20 ng/ml) produced significant potentiation (P < 0.05), which was, however, smaller than that observed with SCF.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailLe "Problem-Based Learning", une révolution ou un progrès attendu ?
Pochet, Bernard ULg

in Revue Française de Pédagogie (1995), (111), 95-107

In recent years, the need for educational reform in education, including university at university level has waited. Leg and Frydman (1978), Frydman and Allegaert (1986) and Vandevelde (1982) ask for many ... [more ▼]

In recent years, the need for educational reform in education, including university at university level has waited. Leg and Frydman (1978), Frydman and Allegaert (1986) and Vandevelde (1982) ask for many years, a "formative school" with emphasis placed on essential development for self-training, a curriculum development including long life learning. Curricula that meet these objectives have been developed and achieved. In the following pages you will find a description of main aspects of these achievements, the "Problem-based Learning". This presentation is mainly based on an analysis of the literature. [less ▲]

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See detailLa péricardiotomie percutanée: traitement non chirurgical d'épanchement péricardique sévère ou récidivant
Bertrand, O.; Legrand, Victor ULg; Kulbertus, Henri ULg

in Revue Médicale de Liège (1995), 50(4), 175-7

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See detailApproche diagnostique et physiopathologique de la maladie d'Alzheimer par la tomographie a émission de positons
Salmon, Eric ULg

in Revue Médicale de Liège (1995), 50(4), 178-81

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See detailQuantitative Analysis of Non-Steroidal Anti-Inflammatory Drugs by Capillary Zone Electrophoresis
Bechet, Isabelle; Hubert, Philippe ULg; Crommen, Jacques ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (1995), 13(4-5), 497-503

The potential utility of capillary zone electrophoresis (CZE) for the separation and quantitative determination of some non-steroidal anti-inflammatory drugs (NSAIDs) was investigated. The influence of ... [more ▼]

The potential utility of capillary zone electrophoresis (CZE) for the separation and quantitative determination of some non-steroidal anti-inflammatory drugs (NSAIDs) was investigated. The influence of different parameters on migration times, peak symmetry, efficiency and resolution was studied; these parameters included the nature and concentration of the anionic and cationic components of the separation buffer. A buffer consisting of 75 mM glycine adjusted to pH 9.1 with triethanolamine was found to provide a very efficient and stable electrophoretic system for the CZE analysis of NSAIDs, giving RSD values of about 0.1 and 0.5% for the within-day reproducibility of migration times and peak areas, respectively at a concentration of 25 micrograms ml-1 (n = 5). Response was linear from 2-100 micrograms ml-1 for both sulindac and tiaprofenic acid, for which the LOQ values were 2.8 and 1.9 micrograms ml-1, respectively, using UV detection at 280 nm. Accuracy for each drug was 102-103%. [less ▲]

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See detailL'insuffisance rénale aigue
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1995), 50(4), 153-162

L'insuffisance rénale aiguë (IRA) constitue un syndrome fréquent. Le médecin exerce un rôle capital, parfois dans sa genèse, toujours dans sa prévention et son traitement. Cette leçon invite les étudiants ... [more ▼]

L'insuffisance rénale aiguë (IRA) constitue un syndrome fréquent. Le médecin exerce un rôle capital, parfois dans sa genèse, toujours dans sa prévention et son traitement. Cette leçon invite les étudiants à bien comprendre ce syndrome pour l'éviter ou, à défaut, pour le diagnostiquer précocement. Ceci permettra d'en limiter les conséquences redoutables. [less ▲]

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See detailUn cas d'hyponatrémie sévère sous administration de pimozide (Orap)
LECLERCQ, Paul; Canivet, Jean-Luc; Damas, Pierre ULg et al

in Revue Médicale de Liège (1995), 50(4), 151-152

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See detailTranscription factor NF-kB is activated by photosensitization generating oxidative DNA damages
Legrand-Poels, Sylvie ULg; Bours, Vincent ULg; Piret, Bernard et al

in Journal of Biological Chemistry (1995), 270(12), 6925-6934

Reactive oxygen intermediates like hydrogen peroxide (H2O2) have been shown to serve as messengers in the induction of NF-kappa B and, then, in the activation and replication of human immunodeficiency ... [more ▼]

Reactive oxygen intermediates like hydrogen peroxide (H2O2) have been shown to serve as messengers in the induction of NF-kappa B and, then, in the activation and replication of human immunodeficiency virus (HIV)-1 in human cells. Because H2O2 can be converted into the highly reactive OH. at various locations inside the cells, we started to investigate the generation of Reactive oxygen intermediates by photosensitization. This technique is based on the use of a photosensitizer which is a molecule absorbing visible light and which can be located at various sites inside the cell depending on its physicochemical properties. In this work, we used proflavine (PF), a cationic molecule having a high affinity for DNA, capable of intercalating between DNA base pairs. Upon visible light irradiation, intercalated PF molecules oxidize guanine residues and generate DNA single-strand breaks. In lymphocytes or monocytes latently infected with HIV-1 (ACH-2 or U1, respectively), this photosensitizing treatment induced a cytotoxicity, an induction of NF-kappa B, and a reactivation of HIV-1 in cells surviving the treatment. NF-kappa B induction by PF-mediated photosensitization was not affected by the presence of N-acetyl-L-cysteine while strong inhibition was recorded when the induction was triggered by H2O2 or by phorbol 12-myristate 13-acetate. Another transcription factor like AP-1 is less activated by this photosensitizing treatment. In comparison with other inducing treatments, such as phorbol 12-myristate 13-acetate or tumor necrosis factor alpha, the activation of NF-kappa B is slow, being optimal 120 min after treatment. These kinetic data were obtained by following, on the same samples, both the appearance of NF-kappa B in the nucleus and the disappearance of I kappa B-alpha in cytoplasmic extracts. These data allow us to postulate that signaling events, initiated by DNA oxidative damages, are transmitted into the cytoplasm where the inactive NF-kappa B factor is resident and allow the translocation of p50/p65 subunits of NF-kappa B to the nucleus leading to HIV-1 gene expression. [less ▲]

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See detailSustained delivery of 5.F.U. from microspheres of biodegradable polymer in a model of P.V.R. trated by injection of silicon oil
Ryckewaert, M; Grandfils, Christian ULg; Dhermies, F et al

in Investigative Ophthalmology & Visual Science (1995), 36(4), 162

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See detailAnionic polymerization of (meth)acrylic monomers. 22. Anionic polymerization of tert-butyl methacrylate in toluene/THF mixtures : a preliminary approach to the role of solvation/ligation equilibria
Wang, Jin-Shan; Zhang, Hong ULg; Jérôme, Robert ULg et al

in Macromolecules (1995), 28(6), 1758-1764

Although the anionic polymerization of tert-butyl methacrylate (tBMA) induces a narrow and unimodal molecular weight distribution (MWD) when performed in either pure THF or pure toluene at -78 degrees C ... [more ▼]

Although the anionic polymerization of tert-butyl methacrylate (tBMA) induces a narrow and unimodal molecular weight distribution (MWD) when performed in either pure THF or pure toluene at -78 degrees C in the presence of a Lithium counterion, that in THF/toluene mixtures, keeping other conditions unchanged, surprisingly gives rise to broad bi- and even multimodal MWD's. Moreover, with increasing polymerization temperature from -78 to 0 degrees C, that multimodal MWD gets narrower, atypical of termination reactions, and indeed at 0 degrees C, a very narrow unimodal MWD is again obtained. These results have been satisfactorily interpreted in terms of a multiple solvation equilibria mechanism: there coexist several types of THF-solvated and nonsolvated active species and the exchange among them is slow at -78 degrees C but fast at 0 degrees C compared to the monomer propagation rate, thus resulting in a multimodal MWD in the former case and a narrow one in the latter. Furthermore, this solvation mechanism also dominates the stereoregulation of the tBuMA polymerization in mixed solvent. It has indeed been demonstrated that addition of various types of ligands, i.e., lithium chloride (LiCl) and lithium tert-butoxide (LiOtBu) (both mu-ligands), 12-crown-4 (12CE4) and cryptand 211 (K211) (both sigma-chelating ligands), and Lithium 2-(2-methoxyethoxy)ethoxide (LiOE(2)M) (a mu/sigma dual type of ligand), affects the tBMA anionic polymerization in a way which can be accounted for by these so-called solvation/ligation multiple equilibria among THF-nonsolvated, THF-solvated, and Ligated ion pairs. Once again, the fact that, in comparison with 12CE4 and LiOtBu, such ligands as LiOE(2)M, K211, and LiCl can effectively promote a much narrower MWD is nicely related to their high propensity to coordinate with a lithium ester enolate and at the same time to either promote a fast-exchanging ligation equilibrium or form a single type of active complex, in good agreement with the NMR investigation of corresponding model systems as previously reported by us. [less ▲]

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See detailCoproduction of fengycin and iturin, surfactn or mycosubtilin lipopeptides from Bacillus subtilis
Hbid, C.; Jacques, Philippe ULg; Razafindralambo, Hary ULg et al

in Archives of Physiology & Biochemistry (1995), 103

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See detailA kinetic model of the formation of the hot oxygen geocorona. 2: Influence of O(+) ion precipitation
Bisikalo, D. V.; Shematovich, V. I.; Gérard, Jean-Claude ULg

in Journal of Geophysical Research (1995), 100

A model for the oxygen geocorona near the exobase solving the nonlinear Boltzmann equation with a Monte Carlo method is used to calculate the distribution of the hot oxygen atoms during geomagnetically ... [more ▼]

A model for the oxygen geocorona near the exobase solving the nonlinear Boltzmann equation with a Monte Carlo method is used to calculate the distribution of the hot oxygen atoms during geomagnetically disturbed nighttime conditions. The precipitation of energetic O(+) ions and the subsequent enhancement of the hot O corona at high latitudes is simulated for the September 17, 1971, storm conditions. It is found that in such circumstances, the O(+) precipitation is a significant source of superthermal O atoms leading to important perturbations of the velocity distribution of the bulk oxygen population. The effective gas temperature near the exobase is similar to that in the undisturbed atmosphere, but the hot O density rises considerably over the quiet condition values. [less ▲]

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See detailHST Far-Ultraviolet Imaging of Jupiter During the Impacts of Comet Shoemaker-Levy 9
Clarke, John T; Prange, Renee; Ballester, Gilda E et al

in Science (1995), 267

Hubble Space Telescope far-ultraviolet images of Jupiter during the Shoemaker-Levy 9 impacts show the impact regions darkening over the 2 to 3 hours after the impact, becoming darker and more extended ... [more ▼]

Hubble Space Telescope far-ultraviolet images of Jupiter during the Shoemaker-Levy 9 impacts show the impact regions darkening over the 2 to 3 hours after the impact, becoming darker and more extended than at longer wavelengths, which indicates that ultraviolet-absorbing gases or aerosols are more extended, more absorbing, and at higher altitudes than the absorbers of visible light. Transient auroral emissions were observed near the magnetic conjugate point of the K impact site just after that impact. The global auroral activity was fainter than average during the impacts, and a variable auroral emission feature was observed inside the southern auroral oval preceding the impacts of fragments Q1 and Q2. [less ▲]

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See detailA numerical study of the influence of the dirunal cycle on the surface energy and water budgets
Delire, Christine; Gérard, Jean-Claude ULg

in Journal of Geophysical Research (1995), 100

Global models including atmospheric, oceanic, and biogeochemical processes are needed for the study of possible environmental changes, but they require efficient approximations of physical processes in ... [more ▼]

Global models including atmospheric, oceanic, and biogeochemical processes are needed for the study of possible environmental changes, but they require efficient approximations of physical processes in order to reduce the computing time. The need to resolve the dirunal cycle when treating such problems is questionable. The Interaction Soil Biosphere Atmosphere (ISBA) model describing soil-vegetation-atmosphere interactions is used to analyze the importance of the dirunal cycle on the surface energy and water budjets. Stand-alone simulations are first performed using the Hydrologic Atmospheric Pilot EXperiment-MOdélisation du BILan HYdrique (HAPEX-MOBILHY) and Amazonian Region Micrometeorological Experiment (ARME) data sets to assess the need of an explicit dirunal variation of the atmospheric forcing for different sites. As a reference, the run is forced by measured values of atmospheric variables and radiative fluxes. As a test, ISBA is run forced by the 24-hour means of these atmospheric and radiative forcings. The surface and deep water content, the total evaporation, and the net radiation flux are correctly evaluated without the diurnal cycle. In contrast, the interception reservoir is highly overestimated. The model is then coupled with a one-dimensional atmospheic model in which, as test, the solar flux at the top of the atmosphere is replaced by a daily constant mean insolation. The superficial soil moisture content and the total evapotranspiration flux are correctly estimated. The surface temperature and the sensible heat flux are not satisfactorily predicted. Thus it appears that neglecting the diurnal cycle is adequate when considering the hydrologic balance of the surface but not the surface temperature. [less ▲]

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See detailLong-Term Performance in Vitro and in Vivo of Dual-Energy X-Ray Absorptiometry
Reginster, Jean-Yves ULg; Deroisy, Rita ULg; Zegels, Brigitte ULg et al

in Clinical Rheumatology (1995), 14(2), 180-6

Dual-energy X-ray absorptiometry (DXA) is actually considered as one of the most appropriate techniques for measuring bone mineral content (BMC) and bone mineral density (BMD). An anthropomorphic phantom ... [more ▼]

Dual-energy X-ray absorptiometry (DXA) is actually considered as one of the most appropriate techniques for measuring bone mineral content (BMC) and bone mineral density (BMD). An anthropomorphic phantom and a 25-year-old girl were repeatedly measured, 160 times and 50 times respectively, over an 18-month period to investigate performance in vitro and in vivo of a commercial DXA equipment (HOLOGIC QDR 1000). DXA is a highly accurate technique, the BMC and BMD determinations only overestimated the exact value of the phantom by 0.20% and 0.51% respectively. In vivo long-term (18 months) reproducibility of BMD of the spine is characterized by an interassay coefficient of variation (CVt) of 0.8% while, for the different regions of interest of the hip, BMD CVt varies from 1.1% (total zone) to 5.3% (Ward's triangle). In the subject tested, BMD sensitivity for changes of 2.2% at the lumbar spine and 3% at the hip were recorded. [less ▲]

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See detailInfluence of the functionality of the quaternizing agent and the polymer molecular weight on the viscoelastic behaviour of α,ω-(dimethylamino)-polyisoprenes
Charlier, Pascal; Agarwal, Pawan K; Jérôme, Robert ULg

in Polymer (1995), 36(6), 1209-1216

Quaternization of the end-groups of α,ω-(dimethylamino)polyisoprenes with monofunctional, difunctional and trifunctional halides (iodides and bromides) has been undertaken on polymers of different ... [more ▼]

Quaternization of the end-groups of α,ω-(dimethylamino)polyisoprenes with monofunctional, difunctional and trifunctional halides (iodides and bromides) has been undertaken on polymers of different molecular weights (Mn = 6000 and 38000 gmol-l). The thermal stability of the ammonium end-groups is somewhat better when iodide counteranions are present. Quaternization increases the T~ of the material. This effect is more pronounced for low molecular weight chains, especially when a short alkyl group quaternizing agent is used. However, the size of the alkyl or aryl radical has a minor effect on polymer Tj when difunctional quaternizing agents are used. Nevertheless, the modulus of the rubber-like plateau of materials with difunctional agents is higher than with monofunctional quaternizing agents, owing to coupling reactions between the chain-ends. Rheological measurements indicate that the quaternized low molecular weight polyisoprenes exhibit an Arrhenius-type temperature dependence characterized by activation energies which vary between 121 and 146kJmol-1 and suggest that the relaxations attributed to dipole-dipole interactions dominate over long chain entanglements. [less ▲]

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See detailLe cas clinique du mois. A propos d'un cas de pneumopathie à l'amiodarone
Agnant, R. A.; Louis, Renaud ULg; Bury, Thierry ULg et al

in Revue Médicale de Liège (1995), 50(3), 103-4

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See detailValidation of Creatine, Glycogen and L-(+)-Lactate Determination in Biopsy Samples of Bovine Musculus Diaphragma
Desmecht, Daniel ULg; Linden, Annick ULg; Cuvelier-Klimek, M. et al

in Journal of Veterinary Medicine. A, Physiology, Pathology, Clinical Medicine (1995), 42(1), 13-26

Whereas reliable measurements of diaphragmatic force and electrical activity are now available in calves, evidence that substrate contents in the bovine diaphragm can be accurately measured is still ... [more ▼]

Whereas reliable measurements of diaphragmatic force and electrical activity are now available in calves, evidence that substrate contents in the bovine diaphragm can be accurately measured is still lacking. The purposes of the present study were therefore a) to describe and test the reliability of methods and procedures used for sampling, lyophilisation, extraction and dosage of muscular lactate, glycogen and creatine contents and b) to report the variation in their levels found along the bovine diaphragm and among individuals. The repeatability of the results yielded by a) assaying the extracts, b) processing and assaying the extracts and c) taking samples at different sites in the muscle was assessed. Neither assay, nor processing effects were significant (P < or = 0.05). Substrates were found to be homogeneously distributed within the two muscles studied. Substrate contents expressed per unit of muscle weight or total creatine were neither more or less variable than when expressed per unit of dry matter. [less ▲]

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See detailDe ruimtebeleving in Vestdijks Verzamelde Verhalen II
Nachtergaele, Lutgarde ULg

in Vestdijkkroniek (1995), 86

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See detailMatrix Metalloproteinase Family
Baramova, E.; Foidart, Jean-Michel ULg

in Cell Biology International (1995), 19(3), 239-42

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See detailCrosslinked polyimide foams derived from pyromellitic dianhydride and 1,1-bis(4-aminophenyl)-1-phenyl-2,2,3-trifluoroethane with poly(α-methylstyrene)
Charlier, Y.; Hedrick, James L; Russel, T. P. et al

in Polymer (1995), 36(6), 1315-1320

A new route for the synthesis of high glass transition temperature, thermally stable polymer foams with pore sizes in the nanometre regime has been developed, using compositionally asymmetric microphase ... [more ▼]

A new route for the synthesis of high glass transition temperature, thermally stable polymer foams with pore sizes in the nanometre regime has been developed, using compositionally asymmetric microphase-separated block copolymers where the minor component (poly(α-methylstyrene)) is thermally labile and the major component (polyimide) is thermally stable. The minor component can unzip to its monomer upon heating, and the decomposition products can diffuse out of the film, leaving behind pores embedded in a matrix of the thermally stable component. In this study, the polyimide block was crosslinked with ethynyl functionalities to obtain a stable porous structure. The decomposition of the α-methylstyrene in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild conditions were required to avoid rapid depolymerization of the α-methylstyrene and plasticization of the polyimide matrix. The foams showed pore sizes with diameters up to a micrometre in size as well as the expected reduction in the mass density. However, the crosslinking of the matrix as a means of stabilizing the expected nanofoams was not successful. [less ▲]

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See detailVERTICAL COLUMN ABUNDANCES OF HCN DEDUCED FROM GROUND-BASED INFRARED SOLAR SPECTRA - LONG-TERM TREND AND VARIABILITY
Mahieu, Emmanuel ULg; RINSLAND, C. P.; Zander, Rodolphe ULg et al

in Journal of Atmospheric Chemistry (1995), 20(3), 299-310

A set of high-resolution IR solar spectra recorded at the International Scientific Station of the Jungfraujoch, Switzerland, from 84/06 to 93/06, and at the National Solar Observatory McMath-Pierce solar ... [more ▼]

A set of high-resolution IR solar spectra recorded at the International Scientific Station of the Jungfraujoch, Switzerland, from 84/06 to 93/06, and at the National Solar Observatory McMath-Pierce solar telescope facility on Kitt Peak, Arizona, U.S.A. from 78/05 to 92/07 have been analyzed to determine the vertical column abundances of hydrogen cyanide, HCN, above the two stations. The analysis was based on least-squares curve fitting of calculated spectra to the observations encompassing the P4 and the P8 lines of HCN respectively located at 3299.5273 and 3287.2483 cm(-1). The results obtained for the two stations indicate that no significant long-term trend affects either of the two databases; however, this analysis reveals variable increases during springtime of up to a factor of 2 in the HCN total column above the Jungfraujoch and even up to 3 above Kitt Peak. The calculated mean vertical column abundances, excluding the spring observations, are equal to (2.55 +/- 0.30) x 10(15) molec./cm(2) (S.D.) and (2.75 +/- 0.30) x 10(15) molec./cm(2) respectively above the Jungfraujoch and the Kitt Peak observatories. Based on a realistic volume mixing ratio profile, these columns translate into mean volume mixing ratios equal to 190 x 10(-12) ppv at the respective altitudes of the stations. [less ▲]

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See detailAttraction, narration et culture de classe. Trois voyages dans la mine
Mélon, Marc-Emmanuel ULg

in Revue belge du cinéma (1995), 38-39

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See detailNeutrophil Phagocyte Dysfunction in a Weimaraner with Recurrent Infections
Hansen, P.; Clercx, Cécile ULg; Henroteaux, Marc ULg et al

in Journal of Small Animal Practice (1995), 36(3), 128-31

A five-and-a-half-month-old male weimaraner with severe recurrent bacterial infections was assessed for immunocompetence. Results revealed a low serum immunoglobulin G concentration and defective ... [more ▼]

A five-and-a-half-month-old male weimaraner with severe recurrent bacterial infections was assessed for immunocompetence. Results revealed a low serum immunoglobulin G concentration and defective neutrophil phagocytosis. [less ▲]

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See detailLe BOOP: bronchiolitis obliterans and organising pneumonia, mythe ou réalité?
Weber, T.; Louis, Renaud ULg; Bury, Thierry ULg et al

in Revue Médicale de Liège (1995), 50(3), 108-9

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See detailEndogenous Glutamate Involvement in Pulsatile Secretion of Gonadotropin-Releasing Hormone: Evidence from Effect of Glutamine and Developmental Changes
Bourguignon, Jean-Pierre ULg; Gerard, Arlette ULg; Alvarez Gonzalez, Maria-Luz ULg et al

in Endocrinology (1995), 136(3), 911-6

The secretion of GnRH can be stimulated by glutamate (GLU) and GLU agonists, whereas GLU receptor antagonists inhibit GnRH. Using 6-diazo-5-oxo-L-norleucine (DON), an inhibitor of glutaminase, we aimed to ... [more ▼]

The secretion of GnRH can be stimulated by glutamate (GLU) and GLU agonists, whereas GLU receptor antagonists inhibit GnRH. Using 6-diazo-5-oxo-L-norleucine (DON), an inhibitor of glutaminase, we aimed to study the involvement of endogenous GLU in GnRH secretion through the effects of impaired GLU biosynthesis from its precursor glutamine (GLN). GnRH secretion by hypothalamic explants of male rats, aged 15 and 50 days, was compared, because the frequency of spontaneous GnRH secretory pulses showed a 2-fold increase between those two ages. Using explants of 50-day-old rats, GLN elicited GnRH secretion in a similar dose-related manner as GLU. DON prevented GLN-evoked secretion of GnRH, whereas the effect of GLU was not altered. DON also markedly inhibited spontaneous pulsatile secretion of GnRH and the secretory response to veratridine, a Na+ channel opener. The inhibitory effect of DON on veratridine-evoked secretion of GnRH was directly related to the duration of exposure to DON and the frequency of GnRH secretory episodes. Using explants of 15-day-old rats, GLN could elicit GnRH release, although this response was lower than GLU-evoked secretion of GnRH. The DON concentrations required for inhibition of veratridine-evoked secretion of GnRH were lower at 15 days than at 50 days. These data indicate that 1) GLU biosynthesis from GLN is a prerequisite to the physiological mechanism of pulsatile GnRH secretion; and 2) inhibition of veratridine- or GLN-induced secretion of GnRH requires higher DON concentrations after the onset of puberty than before. This suggests that glutaminase, the enzyme controlling GLU biosynthesis from GLN, shows increased activity after the onset of puberty when the frequency of pulsatile GnRH secretion is increased as well. [less ▲]

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See detailSuperovulation of goats with purified pFSH supplemented with defined amounts of pLH
Nowshari, M. A.; Beckers, Jean-François ULg; Holtz, W.

in Theriogenology (1995), 43

The superovulatory response of goats treated with purified pFSH supplemented with 30, 40 or 50% pLH was compared. Sixty-four Boer goat does were synchronized by progestagen-containing ear implant ... [more ▼]

The superovulatory response of goats treated with purified pFSH supplemented with 30, 40 or 50% pLH was compared. Sixty-four Boer goat does were synchronized by progestagen-containing ear implant, randomly allotted to 3 groups and, beginning 2 d before implant removal, treated with purified pFSH supplemented with 30, 40 or 50% pLH. Each animal received 16 Armour Units of pFSH administered in 6 descending doses at 12-h intervals. Along with the last 2 injections, the does received 5 mg PGF(2alpha). Embryos were flushed either surgically or after slaughter on Day 5 or 6 after the last day of standing estrus. The percentage of animals responding to treatment was not different among groups treated with pFSH supplemented with 30, 40 or 50% pLH (76, 71 and 63%, respectively). The corresponding data for number of ovulations was 11.3 +/- 1.6, 16.3 +/- 1.8 and 16.4 +/- 2.6, for number of ova and embryos recovered 8.1 +/- 1.9, 12.0 +/- 1.5 and 13.5 +/- 2.9 and for number of transferable embryos 6.6 +/- 1.9, 9.1 +/- 1.5 and 7.1 +/- 2.1 (x +/- SEM). Results confirm the earlier finding of a good response of goats to pFSH preparations with a high FSH:LH ratio, and, although group differences were statistically nonsignificant (P > 0.05), they suggest that supplementation with approximately 40% pLH may be close to the optimum [less ▲]

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