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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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 detailEtude de la variabilité sinusale par analyses temporelle et spectrale: intérêt clinique et perspectives
Bilge, A.; Pierard, Luc ULg; Kulbertus, Henri ULg

in Revue Médicale de Liège (1995), 50(3), 120-5

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

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

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

in Vestdijkkroniek (1995), 86

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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 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 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 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 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 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 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 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 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 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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See detailPlasticization of biphasic ionomers by chemically identical, short, monofunctional oligomers
Plante, Michel; Bazuin, C Géraldine; Jérôme, Robert ULg

in Macromolecules (1995), 28(5), 1567-1574

Blends of carboxylated polystyrene ionomers containing 7 mol% of ionic units and carboxylate-terminated, monofunctional, monodisperse styrene oligomers of MW 800 were investigated by dynamic mechanical ... [more ▼]

Blends of carboxylated polystyrene ionomers containing 7 mol% of ionic units and carboxylate-terminated, monofunctional, monodisperse styrene oligomers of MW 800 were investigated by dynamic mechanical analysis and small angle X-ray scattering(SAXS). Both Cs and Ba carboxylate salts were studied,as well as blends of the Cs oligomer with homopolystyrene. The cluster phase is preferentially plasticized by the oligomers for both salts.; However, whereas the nonclustered phase of the Cs system is only a Little more plasticized than that of the Ba system, the cluster phase in the Cs system undergoes dramatic plasticization, the cluster transition disappearing at 5 wt % oligomer content. Simultaneously, the SAXS ''ionomer peak'' disappears. A peak reappears at 20 wt % oligomer content, suggesting the development of a new morphology, proposed to be micelles or ''inverted multiplets''. The difference between the two systems is attributed to the much stronger electrostatic interactions in the Ba system; this is analyzed in terms of elementary ion units. It is concluded that, whereas the nature of the nonpolar tail is relatively unimportant, the nature and strength of the electrostatic interactions involved can be of critical importance to the plasticization effects in blends of ionomers with short, monofunctional oligomers. [less ▲]

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See detailDesign of electrical conductive composites : key role of the morphology on the electrical properties of carbon black filled polymer blends
Gubbels, Frédéric; Blacher, Silvia ULg; Vanlathem, E. et al

in Macromolecules (1995), 28(5), 1559-1566

Effect of carbon black (CB) on the morphology of filled polyethylene (PE)/polystyrene (PS) blends has been investigated by image analysis of optical micrographs (2-D analysis) and by the selective ... [more ▼]

Effect of carbon black (CB) on the morphology of filled polyethylene (PE)/polystyrene (PS) blends has been investigated by image analysis of optical micrographs (2-D analysis) and by the selective extraction of one phase of the binary blends (3-D analysis). The macroscopic electrical resistivity of the filled polyblends strongly depends on the selective localization of CB in one phase or at the interface and above all on the double percolation, i.e. percolation of the polymer phases and percolation of the CB particles. The selective localization of CB in the PE phase has remarkable effects on the polyblend phase morphology. The phase cocontinuity is indeed extended over a much larger composition range, and the phase morphology is stabilized toward post-thermal treatment at 200 degrees C. In the case of double percolation and selective localization of CB at the polyblend interface, electrical conductivity is observed at a CB content as low as 0.4 wt %. [less ▲]

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See detailFungi die onychomycosis veroorzaken in Nederland
Nikkels, Arjen ULg; Arrese Estrada, Jorge ULg; Pierard, Gérald ULg

in Nederlands Tijdschrift voor Geneeskunde (1995), 139

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See detailOverproduction and properties of the mannuronate alginate lyase AlxMB
Malissard, Martine; Chavagnat, Frédéric; Duez, Colette ULg et al

in FEMS Microbiology Letters (1995), 126(2), 105-111

In previous studies (Malissard et al., FEMS Microbiol. Lett. (1993) 110, 101-106), the alginate lyase AlxM of the marine bacterium ATCC 433367 was produced in Escherichia coli TC4/pAL-A3 with a yield of ... [more ▼]

In previous studies (Malissard et al., FEMS Microbiol. Lett. (1993) 110, 101-106), the alginate lyase AlxM of the marine bacterium ATCC 433367 was produced in Escherichia coli TC4/pAL-A3 with a yield of 50 mu g per litre of culture. The polypeptide chain was cleaved between two cysteine residues, C169 and C183, themselves linked by a disulphide bridge. AlxM has now been overproduced in E. coli BL21(DE3)/pAL-Sur/pLysS. Under conditions in which formation of inclusion bodies can be avoided, the enzyme is synthesized as a catalytically active, water-soluble, unnicked polypeptide with a yield of 32 mg per litre of culture. It has been purified to protein homogeneity using a one-step procedure. The nicked ALxM(A) and unnicked ALxM(B) alginate lyases have identical alginate-degrading activities at high salt concentrations. [less ▲]

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See detailExcitation spectrum of FE2+ in a tetrahedral potential - Dynamic Jahn-Teller effect
Colignon, David ULg; Kartheuser, Eduard ULg; Rodriguez, Sergio et al

in Physical Review. B : Condensed Matter (1995)

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See detailThe importance of new chemical sources for the hot oxygen geocorona
Gérard, Jean-Claude ULg; Richards, P. G.; Shematovich, V. I. et al

in Geophysical Research Letters (1995), 22

Exothermic reactions involving metastable neutrals and ions were recently proposed as sources of hot oxygen atoms in addition to the classical O2(+) and NO(+) dissociative recombination. The Boltzmann ... [more ▼]

Exothermic reactions involving metastable neutrals and ions were recently proposed as sources of hot oxygen atoms in addition to the classical O2(+) and NO(+) dissociative recombination. The Boltzmann equations for thermal and nonthermal populations of O atoms are solved with Monte Carlo stochastic simulation method. It is shown that the calculated energy distribution functions of O atoms are significantly in nonequilibrium in the transition region between the thermosphere and the exosphere. It is found that the inclusion of additional sources leads to stronger disturbances of the energy distribution function and, as a consequence, increases the nonthermal fraction of hot O atoms. The variation of the vertical distribution of hot O between solar maximum and minimum conditions is also evaluated and shows good agreement with the available experimental evidence. [less ▲]

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See detailElectrical resistivity of AnT2Al3 (An = Np, Pu; T = Ni, Pd)
Seret, Alain ULg; Wastin, Franck; Waerenborgh, Joan-Carlos et al

in Physica B: Condensed Matter (1995), 206 & 207

Structural data and resistivity studies of NpNi2Al3, NpxU1−xPd2Al3 (x = 1, 0.5, 0.3, 0.1) and PuPd2Al3 are reported. The resistivity curves display Kondo features and clear anomalies at the magnetic ... [more ▼]

Structural data and resistivity studies of NpNi2Al3, NpxU1−xPd2Al3 (x = 1, 0.5, 0.3, 0.1) and PuPd2Al3 are reported. The resistivity curves display Kondo features and clear anomalies at the magnetic transition. Moreover, at least two kinds of magnetic structure exist in these compounds, one favouring the electrical conductivity and the other decreasing it. [less ▲]

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See detailMagnetic properties of Np2T2Sn compounds
Sanchez, Jean-Pierre; Colineau, E.; Jeandey, C. et al

in Physica B: Condensed Matter (1995), 206 & 207

The magnetic properties of the Np2T2Sn series investigated by 237Np Mössbauer spectroscopy are reported. Magnetic ordering is shown to occur for T --- Ni, Pd, Pt, whereas the Np ions do not carry a local ... [more ▼]

The magnetic properties of the Np2T2Sn series investigated by 237Np Mössbauer spectroscopy are reported. Magnetic ordering is shown to occur for T --- Ni, Pd, Pt, whereas the Np ions do not carry a local moment when T --- Co, Ru, Rh. Comparisons are made with the corresponding Np2T2In and U2T2Sn compounds. [less ▲]

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See detailLong-term photometry of variables at ESO. III. The third data catalogue (1990-1992).
Manfroid, Jean ULg; Sterken, C.; Cunow, B. et al

in Astronomy and Astrophysics. Supplement Series (1995), 109

In this paper we present the third catalogue of photometric data in the Stroemgren system obtained during the period October 1990-January 1992 in the framework of the Long-Term Photometry of Variables ... [more ▼]

In this paper we present the third catalogue of photometric data in the Stroemgren system obtained during the period October 1990-January 1992 in the framework of the Long-Term Photometry of Variables (LTPV) program at the European Southern Observatory. The catalogue is available in computer readable form at the Centre de Donnees de Strasbourg. [less ▲]

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See detailElectronic properties of U2Ni2Sn
Kindo, Koichi; Fukushima, T.; Kumada, T. et al

in Journal of Magnetism & Magnetic Materials (1995), 140-144(2), 1369-1370

We report on the bulk electronic properties of U2Ni2Sn, which crystallizes in the tetragonal U3Si2 structure. Pronounced anomalies in the temperature dependencies of magnetic susceptibility, specific heat ... [more ▼]

We report on the bulk electronic properties of U2Ni2Sn, which crystallizes in the tetragonal U3Si2 structure. Pronounced anomalies in the temperature dependencies of magnetic susceptibility, specific heat and electrical resistivity indicate magnetic ordering below TN = 26 K. An antiferromagnetic ground state is corroborated by the occurrence of three metamagnetic transitions at about 30, 39 and 51 T in the field dependence of the magnetization. The lack of any saturation tendency in the highest field applied (57 T) may suggest further transition(s) to occur in even higher fields. [less ▲]

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See detailPeroxidase-Catalysed Oxidation of Different Dibenzazepine Derivatives
Liégeois, Jean-François ULg; Rogister, F.; Delarge, J. et al

in Archiv der Pharmazie (1995), 328(2), 109-12

According to a recent hypothesis suggesting the potential role of free radical formation in the clozapine-induced agranulocytosis, we have evaluated the susceptibility to the peroxidase-mediated oxidation ... [more ▼]

According to a recent hypothesis suggesting the potential role of free radical formation in the clozapine-induced agranulocytosis, we have evaluated the susceptibility to the peroxidase-mediated oxidation of different dibenzazepine analogues. On the one hand, compounds with an arylamine group such as clozapine or isoclozapine present a high reactivity in the horseradish peroxidase or myeloperoxidase systems and, on the other hand, fluperlapine, though known to induce agranulocytosis, and other dibenzothiazepine and dibenzoxazepine derivatives appear insensitive to oxidation. Consequently, among tricyclic derivatives, the way of diaryloxa- and diarylthiazepine compounds could be an alternative for the development of safer drugs such as antipsychotics. [less ▲]

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See detailLe cas clinique du mois. A propos d'un cas de sécrétion ectopique d'ACTH
Biessaux, Yves ULg; Paquot, Nicolas ULg; Scheen, A. J. et al

in Revue Médicale de Liège (1995), 50(2), 55-6

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See detailAmpd, Essential for Both Beta-Lactamase Regulation and Cell Wall Recycling, Is a Novel Cytosolic N-Acetylmuramyl-L-Alanine Amidase
Jacobs, Christine ULg; Joris, Bernard ULg; Jamin, M. et al

in Molecular Microbiology (1995), 15(3), 553-9

In enterobacteria, the ampD gene encodes a cytosolic protein which acts as a negative regulator of beta-lactamase expression. It is shown here that the AmpD protein is a novel N-acetylmuramyl-L-alanine ... [more ▼]

In enterobacteria, the ampD gene encodes a cytosolic protein which acts as a negative regulator of beta-lactamase expression. It is shown here that the AmpD protein is a novel N-acetylmuramyl-L-alanine amidase (E.C.3.5.1.28) participating in the intracellular recycling of peptidoglycan fragments. Surprisingly, AmpD exhibits an exclusive specificity for substrates containing anhydro muramic acid. This anhydro bond is mainly found in the peptidoglycan degradation products formed by the periplasmic lytic transglycosylases and thus might behave as a 'recycling tag' allowing the enzyme to distinguish these fragments from the newly synthesized peptidoglycan precursors. The AmpD substrate (or substrates) which accumulates in the absence of the corresponding enzymatic activity acts as an intracellular positive effector for beta-lactamase expression and might represent an element of a communication network between the chromosome and the cell wall peptidoglycan. [less ▲]

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See detailThe role of agrometeorological data bases and software in agrometeorological training in developing countries.
Tychon, Bernard ULg; Tonnard, Victor

in FAO Agrometeorology series (1995), 13

The paper covers a Belgian agrometeorological training course intended for francophone students from developing countries who have completed a minimum of four years training in agrometeorology. Today ... [more ▼]

The paper covers a Belgian agrometeorological training course intended for francophone students from developing countries who have completed a minimum of four years training in agrometeorology. Today, many of our students are heads of agrometeorological departments and divisions. THey are interested in everything that could promote agrometeorological methods to preserve food security and the natural resources of their country. During the past few years, the students have been trained in using microcomputers and solving simple agro-meteorological problems as part of the course. The results obtained so far can now be evaluated, since the microcomputer training began a few years ago; some comments on the future development of this approach are presented. [less ▲]

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See detailMagnetism in U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Svoboda, P. et al

in Journal of Magnetism & Magnetic Materials (1995), 140-144(2), 1367-1368

Magnetic and other electronic properties are presented for the U2T2X compounds (T = late transition metal, X = Sn or In), that crystallize in the tetragonal U3Si2-type structure. They show the formation ... [more ▼]

Magnetic and other electronic properties are presented for the U2T2X compounds (T = late transition metal, X = Sn or In), that crystallize in the tetragonal U3Si2-type structure. They show the formation of 5f magnetic moments and antiferromagnetic ordering in compounds where weak 5f-d hybridization is expected. Near the onset of magnetic ordering strongly enhanced γ-values are found. Neutron-diffraction experiments on U2Pd2Sn and U2Pd2In point to a connection between the mutual coordination of U atoms and the type of magnetic anisotropy [less ▲]

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See detailMacrofagos e factor a de necrose tumoral na necrolise epidermica toxica
Paquet, Philippe ULg; Nikkels, Arjen ULg; Arrese Estrada, Jorge ULg et al

in Arquivos de Dermatologia (1995), 2

ANTECEDENTES: Estudiamos las características inmunopatològicas de 5 casos de necrólisis epidérmica tóxica utilizando un amplio panel de anticuerpos. OSERVACIONES: El patrón y grado del infiltrado celular ... [more ▼]

ANTECEDENTES: Estudiamos las características inmunopatològicas de 5 casos de necrólisis epidérmica tóxica utilizando un amplio panel de anticuerpos. OSERVACIONES: El patrón y grado del infiltrado celular inflamatorio varió dependiendo del estado de la enfermedad. La principal característica constante fue la importante implicación de la línea monocito-macrófago, incluyendo dendrocitos factor XIIIa+ HLA-DR+ y macrófagos CD68+ Mac 387+, antes y durante la necrosis epidérmica. El número de linfocitos CD4+ y CD8+ era comparativamente reducido. Ello se asociaba con un denso marcaje para el factor de necrosis tumoral alfa en la epidermis. CONCLUSIONES: Las células de estirpe monocito-macrófago superan en nùmero ampliamente a los linfocitos en las lesiones de la necrólisis epidérmica tóxica. El factor de necrosis tumoral alfa es problablemente una de las citocinas principales responsables de la necrosis. [less ▲]

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See detailMagnetic kinetic growth-models
Ausloos, Marcel ULg; Vandewalle, Nicolas ULg; Cloots, Rudi ULg

in Journal of Magnetism & Magnetic Materials (1995), 140(Part 3), 2185-2186

Magnetic kinetic growth models are kinetic growth model(s), like the Eden or the DLA models, but allow for the growth to have an extra degree of freedom (a 'spin') which can be coupled to an external ... [more ▼]

Magnetic kinetic growth models are kinetic growth model(s), like the Eden or the DLA models, but allow for the growth to have an extra degree of freedom (a 'spin') which can be coupled to an external field. Two-dimensional simulations show interesting morphologies and parameter dependences. [less ▲]

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See detailSpecificity and Sensitivity of Temporalis Es2 Measurements in the Diagnosis of Chronic Primary Headaches
Wang, W.; De Pasqua, Victor ULg; Gérard, P. et al

in Headache (1995), 35(2), 85-8

We have evaluated the specificity and sensitivity of temporalis ES2 measurements for the diagnosis of primary headaches. Ninety-four outpatients diagnosed according to IHS criteria were prospectively ... [more ▼]

We have evaluated the specificity and sensitivity of temporalis ES2 measurements for the diagnosis of primary headaches. Ninety-four outpatients diagnosed according to IHS criteria were prospectively included: 25 had chronic tension-type headache (code 2.2.), 15 episodic tension-type headache (code 2.1.), 20 migraine without aura (code 1.1.) and 34 chronic daily headaches with daily analgesics/ergotamine abuse (code 8.2.). In chronic tension-type, the sensitivity of the ES2 test was 84% at the 0.1 and the 0.5 Hz, but only 56% at the 2Hz stimulation rates. Its specificity was 100% at 0.1Hz, 90% at 0.5Hz and 95% at 2Hz compared to migraine; positive predictive values were at similar levels. Sensitivity of ES2 at 0.1 Hz was 67% in episodic tension-type headache, but its positive predictive value versus migraine was excellent. Comparing chronic tension-type headache and analgesic abusers, the specificity and positive predictive value of the ES2 test for diagnosing chronic tension-type headache were less satisfactory (60%) while the negative predictive values, however, remained good (83% at 0.1Hz). The results confirm that the temporalis ES2 test has a higher diagnostic sensitivity in chronic and episodic tension-type headache, but that it has a high negative predictive value for both types of tension-type headache compared to other primary headaches. For diagnostic purposes, the 0.1Hz stimulation rate seems optimal. The 2Hz stimulation rate is the least sensitive, although it may induce total disappearance of ES2 in up to 40% of patients. ES2 is of limited usefulness for separating chronic tension-type headache and chronic drug-abuse headache, possibly because the latter group comprises both tension-type headache and migraine patients. [less ▲]

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See detailSimulated growth and microstructure of DyBa2Cu3O7-X with and without Dy2BaCUO5 addition
Vandewalle, Nicolas ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg

in Journal of Materials Research (1995), 10(2), 268-273

We present optical observations of magnetically melt-textured DyBa2Cu307-x with and without 20 wt. % excess of Dy2BaCu05. From these observations, we propose some kinetic mechanism of the growth of 123 ... [more ▼]

We present optical observations of magnetically melt-textured DyBa2Cu307-x with and without 20 wt. % excess of Dy2BaCu05. From these observations, we propose some kinetic mechanism of the growth of 123 compounds. Kinetic processes can simulated on computers. Two (very) simple models derived from the well-known Eden model are presented. They simulate the growth of the grain front. The simulated patterns agree with the observations. The microstructure of such materials cannot be explained by thermodynamic and chemical considerations alone, but explanations must include the kinetics of the growth front as well. From our observations, we conclude that the growth probability ratios g(110)/g(100)/g(001) are of the order of 10 and 50, respectively. [less ▲]

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See detailComment j'explore un patient hypertendu
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1995), 50(2), 91-92

Des examens complémentaires consitituent une étape importante de la prise en charge d'un patient hypertendu. Du bilan de base simple, peu coûteux et à appliquer à tous, aux examens paracliniques les plus ... [more ▼]

Des examens complémentaires consitituent une étape importante de la prise en charge d'un patient hypertendu. Du bilan de base simple, peu coûteux et à appliquer à tous, aux examens paracliniques les plus sophistiqués, la prescription nécessite cependant une personnalisation. II n'y a en effet pas une hypertension à explorer, mais des hypertendus, fort différents entre eux. Les examens à recommander vont cerner l'état actuel cardiaque, artériel et rénal ainsi que le profil de risque cardiovasculaire. Ils vont aussi rechercher une cause à l'élévation de pression si la clinique, l'anamnèse et quelques examens de laboratoire le suggèrent. [less ▲]

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See detailContribution of Mutant Analysis to the Understanding of Enzyme Catalysis: The Case of Class a Beta-Lactamases
Matagne, André ULg; Frère, Jean-Marie ULg

in Biochimica et Biophysica Acta (1995), 1246(2), 109-27

Class A beta-lactamases represent a family of well studied enzymes. They are responsible for many antibiotic resistance phenomena and thus for numerous failures in clinical chemotherapy. Despite the facts ... [more ▼]

Class A beta-lactamases represent a family of well studied enzymes. They are responsible for many antibiotic resistance phenomena and thus for numerous failures in clinical chemotherapy. Despite the facts that five structures are known at high resolution and that detailed analyses of enzymes modified by site-directed mutagenesis have been performed, their exact catalytic mechanism remains controversial. This review attempts to summarize and to discuss the many available data. [less ▲]

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See detailSimulation of Human B-Lymphocyte Proliferation by Agm-1470, a Potent Inhibitor of Angiogenesis
Antoine, Nadine ULg; Bours, Vincent ULg; Heinen, Ernst ULg et al

in Journal of the National Cancer Institute (1995), 87(2), 136-9

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See detailLes infections cutanées dues à l'herpès
Nikkels, Arjen ULg

in Actualités Médicales Belges (1995), 8(450),

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See detailSynthesis and Processing of Bovine Herpesvirus-1 Glycoprotein H
Baranowski, Eric; Dubuisson, Jean; van Drunen Little-van den Hurk, Sylvia et al

in Virology (1995), 206(1), 651-4

The translation product of the bovine herpesvirus-1 (BHV-1) gH gene was identified and characterized. Synthetic peptides were used to generate specific antisera and a glycoprotein of 108K was precipitated ... [more ▼]

The translation product of the bovine herpesvirus-1 (BHV-1) gH gene was identified and characterized. Synthetic peptides were used to generate specific antisera and a glycoprotein of 108K was precipitated by one of the antisera. Cross-immunoprecipitations with monoclonal antibodies to BHV-1 glycoprotein gp108 and the anti-gH peptide antiserum demonstrated that gp108 is the translation product of the gH open reading frame. Glycoprotein gH synthesis and intracellular processing was analyzed in infected Madin-Darby bovine kidney cells using anti-gp 108 monoclonal antibodies. Glycoprotein gH is expressed as a beta-gamma protein and could be detected by radioimmunoprecipitation as early as 2 hr postinfection. Cotranslational N-glycosylation of gH is essential for the recognition by monoclonal antibodies, suggesting that N-linked glycans are involved in protein folding or that they are targets for most of monoclonal antibodies used in this study. [less ▲]

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See detailKinetic Study of Interaction between Brl 42715, Beta-Lactamases, and D-Alanyl-D-Alanine Peptidases
Matagne, André ULg; Ledent, Philippe; Monnaie, Didier et al

in Antimicrobial Agents and Chemotherapy (1995), 39(1), 227-31

A detailed kinetic study of the interactions between BRL 42715, a beta-lactamase-inhibiting penem, and various beta-lactamases (EC 3.5.2.6) and D-alanyl-D-alanine peptidases (DD-peptidases, EC 3.4.16.4 ... [more ▼]

A detailed kinetic study of the interactions between BRL 42715, a beta-lactamase-inhibiting penem, and various beta-lactamases (EC 3.5.2.6) and D-alanyl-D-alanine peptidases (DD-peptidases, EC 3.4.16.4) is presented. The compound was a very efficient inactivator of all active-site serine beta-lactamases but was hydrolyzed by the class B, Zn(2+)-containing enzymes, with very different kcat values. Inactivation of the Streptomyces sp. strain R61 extracellular DD-peptidase was not observed, and the Actinomadura sp. strain R39 DD-peptidase exhibited a low level of sensitivity to the compound. [less ▲]

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See detailHypercholestérolémie modérée et coronaropathies: étude MAAS et étude 4S
Martinez, Christophe ULg; Legrand, Victor ULg; Kulbertus, Henri ULg

in Revue Médicale de Liège (1995), 50(1), 35-40

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See detailIncreased Expression of Osteonectin and Osteopontin, Two Bone Matrix Proteins, in Human Breast Cancer
Bellahcene, Akeila ULg; Castronovo, Vincenzo ULg

in American Journal of Pathology (1995), 146(1), 95-100

Microcalcifications are a common phenomenon associated with breast cancer and are often the only mammographic sign of a malignant breast disease. Although microcalcifications are not restricted to breast ... [more ▼]

Microcalcifications are a common phenomenon associated with breast cancer and are often the only mammographic sign of a malignant breast disease. Although microcalcifications are not restricted to breast cancer and can be also associated with benign lesions, it is noteworthy that they are composed exclusively of hydroxyapatite in breast carcinoma. Hydroxyapatite is the bone-associated phosphocalcic crystal the deposition of which in bone tissue requires the coordinated expression of several molecules such as osteonectin (OSN) and osteopontin (OPN), synthesized by cells of the osteoblastic lineage. In this study, we evaluated the expression of these two bone matrix proteins, using an immunoperoxidase technique and specific antibodies, in 79 breast lesions including 28 benign and 51 cancerous specimens. We found that normal mammary tissue associated with the lesions examined expressed generally undetectable or lightly detectable (0 or 1+) amounts of OSN and OPN (92 and 81%, respectively). Benign breast lesions, including fibroadenoma and fibrocystic dysplasia, were generally weakly stained (0 or 1+) with both anti-OSN and anti-OPN antibodies (96.4 and 60.7%, respectively). Interestingly, the majority of both in situ and invasive breast carcinoma lesions showed a strong expression (2+ or 3+) for OSN or OPN (74.5 and 84.3%, respectively). High expression of these two bone matrix proteins was associated with frequent microcalcification deposition in the lesion. This study is the first extensive study of OSN and OPN expression in mammary cancers. Our data suggest that OSN and OPN could play a role in the formation of ectopic microcalcifications often associated with breast cancer. It is also tempting to speculate that the expression of these two glycoproteins by breast cancer cells play a role in the preferred bone homing of breast metastases. [less ▲]

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See detailMagnetic diffusion-limited aggregation
Vandewalle, Nicolas ULg; Ausloos, Marcel ULg

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1995), 51(1), 597-603

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See detailInvestigation of the Relationship between Osteoporosis and the Collagenase Gene by Means of Polymorphism of the 5'upstream Region of This Gene
Thiry-Blaise, L. M.; Taquet, A. N.; Reginster, Jean-Yves ULg et al

in Calcified Tissue International (1995), 56

Osteoporosis is a slowly progressing disease resulting from an imbalance between bone accretion and degradation. As interstitial collagenase is a key enzyme in the degradation of bone matrix, we ... [more ▼]

Osteoporosis is a slowly progressing disease resulting from an imbalance between bone accretion and degradation. As interstitial collagenase is a key enzyme in the degradation of bone matrix, we investigated a possible relationship between the collagenase gene and osteoporosis. Analysis of an amplified genomic DNA fragment from -524 to +52 by denaturing gradient gel electrophoresis and sequencing allowed us to detect three dimorphic sites upstream of base -300, one of them leading to a BanI restriction site. None of the sites could be directly associated with osteoporosis. The allele frequencies of the three dimorphic sites were estimated. The interallelic ratios were high, thus providing new useful genetic markers for linkage analysis. When comparing these ratios in osteoporotic and nonosteoporotic subjects, no significant differences could be observed. [less ▲]

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See detailBasic Research and Policy Making for the Development of Vessel Traffic Management Information Systems
Marchal, Jean ULg

in Basic Research and Policy Making (1995)

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See detailLe romancier en projet. Quand André Gide étudiait Georges Simenon
Denis, Benoît ULg

in Bulletin des amis d'André Gide (1995), XXVIII(105), 53-70

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See detailA Prenatal Trisomy 21 Screening Program Using Alpha-Fetoprotein, Human Chorionic Gonadotropin, and Free Estriol Assays on Maternal Dried Blood
Verloes, Alain ULg; Schoos, Roland ULg; Herens, Christian ULg et al

in American Journal of Obstetrics and Gynecology (1995), 172(1, Pt 1), 167-74

OBJECTIVE: The feasibility of large-scale Down syndrome maternal screening with dried blood samples and nonradioactive methods was examined. STUDY DESIGN: A prospective observation study was performed on ... [more ▼]

OBJECTIVE: The feasibility of large-scale Down syndrome maternal screening with dried blood samples and nonradioactive methods was examined. STUDY DESIGN: A prospective observation study was performed on a nonselected population of 11,241 pregnant women sampled between January 1991 and September 1992, between 14 and 24 weeks' gestation (ultrasonographic scanning available for 91.6%), through a multicenter collaborative network. Enzyme-linked immunosorbent assays for alpha-fetoprotein, human chorionic gonadotropin, and free estriol were performed on dried blood samples. Risk determination was made with an in-house software implementing the multivariate gaussian log likelihood method. RESULTS: A total of 10,450 samples were eligible for the study. Mean age at term was 27.9 years. A total of 6.84% of the patients were > or = 35 years old with a prior risk of trisomy 21 > 1:350. The general positive rate of our sample was 8.15%. After calculation 31.7% with prior risk > 1:350 were still in the high-risk group; 6.36% of the low-risk group were found to be at high risk for Down syndrome. Fifteen trisomic pregnancies were observed, of which 11 had a calculated risk higher than the selected cutoff value (1:350). The overall detection rate was 73%, specificity was 92%, and positive predictive power was 1.2%. CONCLUSION: Our pilot study has shown performances within the range of conventional serum screening programs. Dried blood assays are a handy alternative to serum assays. Blot paper cards represent a simple method of sampling, well fitted for large population screening. Combined with nonradioactive methods, this method appears to be both low cost and effective. The current work apparently is the first large-scale Down screening program performed with dried blood. [less ▲]

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See detailTamoxifen and its active metabolite inhibit growth of estrogen receptor-negative MDA-MB-435 cells
Charlier, Corinne ULg; Chariot, Alain ULg; Antoine, Nadine ULg et al

in Biochemical Pharmacology (1995), 49

Tamoxifen (TAM), the non-steroidal anti-estrogen most widely administered to breast cancer patients, acts, at least in part, by competing with estrogen receptors (ER). However, the existence of an ... [more ▼]

Tamoxifen (TAM), the non-steroidal anti-estrogen most widely administered to breast cancer patients, acts, at least in part, by competing with estrogen receptors (ER). However, the existence of an alternative mechanism of action for this drug is supported by the clinical observations that: (a) 30% of patients with ER-negative cancer cells respond to TAM, and (b) 30% of patients with ER-positive cancer cells are not sensitive to this anti-estrogen. In this study, we observed that growth of the human ER-negative breast cancer cell line MDA-MB-435 was inhibited by TAM and 4-hydroxytamoxifen (4OH-TAM) in a concentration-dependent fashion. Both monoclonal enzymoimmunoassay and Dextran Charcoal Coated Scatchard radioimmunoassay analysis demonstrated that this MDA-MB-435 cell line does not express ER. The absence of ER in MDA-MB-435 cells was also demonstrated at the mRNA level by both northern blot hybridization and reverse transcription-polymerase chain reaction techniques. MDA-MB-435 cell proliferation was not affected by 17 beta-estradiol or by the pure anti-estrogen ICI 164384, further demonstrating that the observed effects of TAM and its active metabolite on the proliferation of MDA-MB-435 cells were due to an ER-independent mechanism, yet to be identified. MDA-MB-435 thus appears to be a promising original model for the study of the alternative ER-independent mechanisms of action of TAM. [less ▲]

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See detailComment je traite ... un patient avec une insuffisance cardiaque légère ou modérée?
Pierard, Luc ULg

in Revue Médicale de Liège (1995), 50(1), 5-6

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See detailLa naissance des cités au Proche-Orient
Tunca, Önhan ULg

in Le génie de l'Homme. Des origines à l'écriture (1995)

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See detailRecension de l'ouvrage de Daniel Giovannangeli, "La passion de l'origine"
Steinmetz, Rudy ULg

in Revue Internationale de Philosophie (1995)

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See detailAbsence probable de la translocation Robertsonienne 1/29 en race bovine Blanc Bleu Belge
Nicolas, N.; Hidas, A.; Renaville, Robert ULg et al

in Genetics, Selection, Evolution (1995), 27(4), 377-380

The 1/29 translocation, a structural chromosomal abnormality, is often associated with infertility. For this reason, we wished to know its frequency in the Belgian Blue breed. In this study, none of the ... [more ▼]

The 1/29 translocation, a structural chromosomal abnormality, is often associated with infertility. For this reason, we wished to know its frequency in the Belgian Blue breed. In this study, none of the 138 Belgian Blue bulls karyotyped carried the 1/29 translocation. We calculated that the 1/29 translocation frequency in the Belgian Blue breed must be lower than 0.69% at the 5% level. This result can be explained by the origins of the breed. The Belgian Blue breed is descended from focal dairy breeds and from the Shorthorn breed, which can all be considered to be free of the 1/29 translocation. [less ▲]

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See detailBioremediation of diesel-polluted soils.
Jacques, Ph; Bossrez, S.; Mergeay, M. et al

in Archives Internationales de Physiologie et de Biochimie (1995), 103(B46),

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See detailLes troubles obsessionnels compulsifs
Triffaux, Jean-Marc ULg

in stratégie thérapeutique (1995)

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See detailIdentification of structural determinants controlling human and mouse stromelysin-3 proteolytic activities
Noël, Agnès ULg; Santavicca, M.; Stoll, I. et al

in Journal of Biological Chemistry (1995), 270

Matrix metalloproteinases (matrixins) constitute a group of extracellular proteinases belonging to the metzincin superfamily. They are involved in both physiological and pathological tissue remodeling ... [more ▼]

Matrix metalloproteinases (matrixins) constitute a group of extracellular proteinases belonging to the metzincin superfamily. They are involved in both physiological and pathological tissue remodeling processes, including those associated with cancer progression. Stromelysin-3, which is expressed in most invasive human carcinomas, is a matrix metalloproteinase with unusual functional properties. In particular, its mature form does not cleave any of the major extracellular matrix components. To define critical structural determinants involved in controlling stromelysin-3 proteolytic activity, we have used site-directed mutagenesis. We show that the deletion of at least 175 C-terminal amino-acids is sufficient to endow mouse stromelysin-3 with activities against casein, laminin, and type IV collagen. In the case of the human enzyme, however, a further and single Ala-235 Pro substitution is necessary to observe similar activities. Ala-235, which characterizes human stromelysin-3 among matrixins, is located immediately after the C terminus of the “Met-turn,” which forms a hydrophobic basis for the catalytic zinc atom in the metzincin family. We conclude that human stromelysin-3 has gained specific functional properties during evolution by amino acid substitution in the catalytic zinc environment, and that it represents an attractive target for specific inhibitors that may be used to prevent cancer progression. [less ▲]

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