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See detailOntogenetic variations of thermal optimum for growth, and its implication on thermolabile sex determination in blue tilapia
Baras, E.; Mpo'n'tcha, A.; Driouch, H. et al

in Journal of Fish Biology (2002), 61(3), 645-660

Knowledge of how the optimum temperature for growth (Tdegrees(opt)) varies during ontogeny, and how close it is to the temperatures that induce Phenotypic masculinization is fundamental to the ... [more ▼]

Knowledge of how the optimum temperature for growth (Tdegrees(opt)) varies during ontogeny, and how close it is to the temperatures that induce Phenotypic masculinization is fundamental to the understanding of the evolution of thermolabile sex determinism (TSD) in fishes. In blue tilapia Oreochromis aureus, Tdegrees(opt) is 32.6degrees C at the start of exogenous feeding (10 mg fish) and it decreases by c 1degrees C each time that the fish bode mass increases by an order of magnitude. Temperatures <35degrees C are not sufficient to induce complete phenotypic masculinization. Based on a multiple-regression model (r(2)=0.938) plotting growth against body mass and water temperature. genotypically female tilapia living at high temperatures during the thermosensitive period (21-28 days) and being reversed into phenotypic males should incur an initial growth disadvantage over fish living at Tdegrees(opt) but not over those living at slightly colder temperatures (27-29degrees C). This initial disadvantage would be later compensated for by faster growth because of between-sex growth dimorphism to the detriment of phenotypic females. These arguments suggest that there is no definite pressure against the selection of TSD in blue tilapia and probable other Oreochromis spp. (C) 2002 The Fisheries Society of the British Isles. Published by Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailNovel antiangiogenic effects of the bisphosphonate compound zoledronic acid
Wood, J.; Bonjean, K.; Ruetz, S. et al

in Journal of Pharmacology and Experimental Therapeutics (2002), 302(3), 1055-1061

Bisphosphonate drugs inhibit osteoclastic bone resorption and are widely used to treat skeletal complications in patients with tumor-induced osteolysis. We now show that zoledronic acid, a new generation ... [more ▼]

Bisphosphonate drugs inhibit osteoclastic bone resorption and are widely used to treat skeletal complications in patients with tumor-induced osteolysis. We now show that zoledronic acid, a new generation bisphosphonate with a heterocyclic imidazole substituent, is also a potent inhibitor of angiogenesis. In vitro, zoledronic acid inhibits proliferation of human endothelial cells stimulated with fetal calf serum, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (IC50 values 4.1, 4.2, and 6.9 muM, respectively), and modulates endothelial cell adhesion and migration. In cultured aortic rings and in the chicken egg chorioallantoic membrane assay, zoledronic acid reduces vessel sprouting. When administered systemically to mice, zoledronic acid potently inhibits the angiogenesis induced by subcutaneous implants impregnated with bFGF [ED50, 3 mug/kg (7.5 nmol/kg) s.c.]. These findings indicate that zoledronic acid has marked antiangiogenic properties that could augment its efficacy in the treatment of malignant bone disease and extend its potential clinical use to other diseases with an angiogenic component. [less ▲]

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See detailThe impact of small physical obstacles on upstream movements of six species of fish - Synthesis of a 5-year telemetry study in the River Meuse basin
Ovidio, Michaël ULg; Philippart, Jean-Claude ULg

in Hydrobiologia (2002), 483(1-3), 55-69

In the course of the 'Meuse Salmon 2000' programme, most weirs and dams (3-8 m in height) in the regulated River Meuse have been progressively equipped with new fishways in order to restore the free ... [more ▼]

In the course of the 'Meuse Salmon 2000' programme, most weirs and dams (3-8 m in height) in the regulated River Meuse have been progressively equipped with new fishways in order to restore the free circulation of all amphibiotic fish species. Nevertheless, fish entering into major spawning tributaries are still confronted with various kinds of physical obstacles of which the overall impact on fish migration has never been investigated. In order to test their ability to negotiate physical obstacles, 128 individuals of fish ( Salmo trutta, Thymallus thymallus, Salmo salar, Chondrostoma nasus, Barbus barbus and Esox lucius) were captured several weeks before their spawning migrations and tagged with radio-transmitters. They were tracked from 30 to 466 days in the River Ourthe and six spawning tributaries over the period October 1995 to June 2001. All obstacles recorded in this study have been classified according to their type and main characteristics (i.e. slope, length and height). Results indicated that most fish migrate during or outside the spawning period and that some small obstacles are not as insignificant as initially thought and can significantly disrupt and/or obstruct their upstream movements. There is a need to harmonize interests in the sustainable conservation of fish populations and the development of small-scale hydropower generation and tourism. [less ▲]

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See detailLe cinéma d’animation et ses thanatomorphoses (fragments sur le monstre, la charogne, le montage et l’animation)
Tomasovic, Dick ULg

in Cinémas : revue d'études cinématographiques / Cinémas: Journal of Film Studies (2002), 13(Automne), 143-164

The role and limits of editing in animation film are reconsidered here. It is no longer a matter of perceiving this practice as “simply” assembling shots, associating random elements, linking diverse ... [more ▼]

The role and limits of editing in animation film are reconsidered here. It is no longer a matter of perceiving this practice as “simply” assembling shots, associating random elements, linking diverse pieces and creating a monstrous body, but rather, it is presently regarded as a continual process of managing transitions, shifting between images, transforming inanimate objects, transmuting immobile elements and transfiguring inert beings. Thus, the animation film’s purpose is less phantasmal, to be a giver of life, as it is phantasmagoric, to be an animator of death. [less ▲]

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See detailLa fenêtre implantatoire
PERRIER d'HAUTERIVE, Sophie ULg; Charlet-Renard, Jeanne de Chantal ULg; Goffin, Frédéric ULg et al

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2002), 31(5), 440-55

The implantation window. Background. Embryo implantation is a complex event involving apposition followed by adhesion of the blastocyst to the maternal endometrium, and finally invasion of this ... [more ▼]

The implantation window. Background. Embryo implantation is a complex event involving apposition followed by adhesion of the blastocyst to the maternal endometrium, and finally invasion of this endometrium. Though implantation could occur in any human tissue, the endometrium is the only tissue where embryo implantation cannot occur except during a restricted period called the implantation window. During this window, the endometrium is highly receptive to the embryo. Material and methods. We reviewed the literature concerning the different factors involved in improved endometrial receptivity and implantation. Results. Maternal - embryo crosstalk is favored by the implantation window. Endometrial receptivity results from the acquisition of ligands or receptors facilitating apposition, then adhesion of the embryo, or from the loss of components preventing it. The molecular basis of the implantation window remains to be defined. Conclusion. Despite progress in assisted reproduction technologies, the lack of control of implantation remains a major obstacle to successful pregnancy. It is of prime importance to determine the characteristic features of a receptive endometrium and, among the many markers proposed by in vitro studies, to analyze in humans those demonstrated by knock-out experiments to play a crucial role in mice. [less ▲]

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See detailSystematic regularization of linear inverse solutions of the EEG source localization problem
Phillips, Christophe ULg; Rugg, Michael D; Friston, Karl J

in NeuroImage (2002), 17(1), 287-301

Distributed linear solutions of the EEG source localization problem are used routinely. Here we describe an approach based on the weighted minimum norm method that imposes constraints using anatomical and ... [more ▼]

Distributed linear solutions of the EEG source localization problem are used routinely. Here we describe an approach based on the weighted minimum norm method that imposes constraints using anatomical and physiological information derived from other imaging modalities to regularize the solution. In this approach the hyperparameters controlling the degree of regularization are estimated using restricted maximum likelihood (ReML). EEG data are always contaminated by noise, e.g., exogenous noise and background brain activity. The conditional expectation of the source distribution, given the data, is attained by carefully balancing the minimization of the residuals induced by noise and the improbability of the estimates as determined by their priors. This balance is specified by hyperparameters that control the relative importance of fitting and conforming to prior constraints. Here we introduce a systematic approach to this regularization problem, in the context of a linear observation model we have described previously. In this model, basis functions are extracted to reduce the solution space a priori in the spatial and temporal domains. The basis sets are motivated by knowledge of the evoked EEG response and information theory. In this paper we focus on an iterative "expectation-maximization" procedure to jointly estimate the conditional expectation of the source distribution and the ReML hyperparameters on which this solution rests. We used simulated data mixed with real EEG noise to explore the behavior of the approach with various source locations, priors, and noise levels. The results enabled us to conclude: M Solutions in the space of informed basis functions have a high face and construct validity, in relation to conventional analyses. (ii) The hyperparameters controlling the degree of regularization vary largely with source geometry and noise. The second conclusion speaks to the usefulness of using adaptative ReML hyperparameter estimates. (C) 2002 Elsevier Science (USA). [less ▲]

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See detailComparaison de différents types de compostages de matières organiques diverses non valorisées par les paysans au Rwanda
Culot, Marc ULg; Mbonigaba Muhinda, Jean-Jacques; Maniraguha, J. D.

in Etudes Rwandaises : Série sciences exactes, naturelles et appliquées (2002), 5

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See detailTraining early Alzheimer patients to use a mobile phone
Lekeu, Françoise ULg; Wojtasik, Vinciane ULg; Van der Linden, Martial ULg et al

in Acta Neurologica Belgica (2002), 102(3), 114-121

The mobile phone may be useful to keep in contact with spatially disoriented and memory impaired patients. In keeping with this idea, this study describes the training program developed to teach two ... [more ▼]

The mobile phone may be useful to keep in contact with spatially disoriented and memory impaired patients. In keeping with this idea, this study describes the training program developed to teach two patients with mild Alzheimer's disease (CI and ML) how to use their own mobile phone. Each training session was divided into two parts. In the first part, the spaced-retrieval technique was used to promote the consultation of a card pasted on the back of the phone. The card detailed each stage of phone utilization and which keys had to be pressed to call somebody. In the second part, the patients received repetitive exercises of calling based upon the errorless learning principle. At the end of three-months rehabilitation, the results showed different learning patterns for the patients. ML needed more spaced-retrieval sessions to spontaneously consult the card and to correctly use the phone, compared to CI However, by the repetition of calling exercises, both patients showed a decrease of instruction card consultation, whereas they were still able to correctly call somebody. This learning ability is hypothesized to be a consequence of a relatively preserved procedural memory in both patients. In conclusion, this study highlights the effectiveness of combined specific learning techniques for improving AD patient's autonomy in daily life activities. [less ▲]

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See detailAccelerated postoperative radiation therapy with weekly concomitant boost in high risk patients with squamous-cell carcinoma of the head and neck
Chevalier; Pasche; COUCKE, Philippe ULg et al

in Radiotherapy & Oncology (2002), 64(supp 1), 248

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See detailDevelopment and in vitro characterisation of novel bioresorbable and bioactive composite materials based on polylactide foams and Bioglass (R) for tissue engineering applications
Roether, J. A.; Boccaccini, Aldo R.; Hench, L. L. et al

in Biomaterials (2002), 23(18), 3871-3878

Bioactive and bioresorbable composite materials were fabricated using macroporous poly(DL-lactide) (PDLLA) foams coated with and impregnated by bioactive glass (Bioglass®) particles. Stable and ... [more ▼]

Bioactive and bioresorbable composite materials were fabricated using macroporous poly(DL-lactide) (PDLLA) foams coated with and impregnated by bioactive glass (Bioglass®) particles. Stable and homogeneous Bioglasss coatings on the surface of PDLLA foams as well as infiltration of Bioglass® particles throughout the porous network were achieved using a slurry-dipping technique in conjunction with pre-treatment of the foams in ethanol. The quality of the bioactive glass coatings was reproducible in terms of thickness and microstructure. Additionally, electrophoretic deposition was investigated as an alternative method for the fabrication of PDLLA foam/Bioglass® composite materials. In vitro studies in simulated body fluid (SBF) were performed to study the formation of hydroxyapatite (HA) on the surface of PDLLA/Bioglass® composites. SEM analysis showed that the HA layer thickness rapidly increased with increasing time in SBF. The high bioactivity of the PDLLA foam/Bioglasss composites indicates the potential of the materials for use as bioactive, resorbable scaffolds in bone tissue engineering. [less ▲]

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See detailDemographic and clinical parameters influencing the short-term outcome of anti-tumor necrosis factor (infliximab) treatment in Crohn's disease
Vermeire, S.; Louis, Edouard ULg; Carbonez, A. et al

in American Journal of Gastroenterology (2002), 97(9), 2357-2363

OBJECTIVE: Infliximab is an effective treatment for refractory or fistulizing Crohn's disease (CD). However, about 30% of patients do not respond to infliximab for unknown reasons. Identifying predictive ... [more ▼]

OBJECTIVE: Infliximab is an effective treatment for refractory or fistulizing Crohn's disease (CD). However, about 30% of patients do not respond to infliximab for unknown reasons. Identifying predictive factors of response is important for optimizing clinical management and for better understanding infliximab's mechanisms of action. The aim of this study was to assess whether demographic or clinical parameters influence short-term response to infliximab. METHODS: The first 240 CD patients of the Belgian Infliximab Expanded Access Program were studied for response to infliximab treatment and assessed at 4 (refractory luminal CD) or 10 wk (fistulizing CD) after the first infusion. Detailed demographic and clinical information on age, sex, type of disease (fistulizing or refractory), Crohn's Disease Activity Index score, C-reactive protein (CRP), smoking habits, disease duration, localization of disease, concomitant medication, and previous surgery were obtained from all patients. Logistic regression and decision tree analysis were performed. RESULTS: There were 73.5% responders and 26.5% nonresponders to treatment. Stepwise logistic regression identified age (OR = 0.971, 95% CI = 0.947-0.995, p = 0.018), isolated ileitis (OR = 0.359, 95% CI 0.177-0.728, p = 0.004), and previous surgery (OR 0.429, 95% CI = 0.233-0.787, p = 0.006) as inversely correlated with response, whereas isolated colitis (OR = 1.905, 95% CI = 1.010-3.597, p = 0.046) and concomitant immunosuppressive treatment (OR = 2.670, 95% CI = 1.430-5.016, p = 0.0022) were positively correlated with response to infliximab. Surprisingly, smoking habits were not retained as predictors for response. Decision tree analysis provided a working algorithm based on age and immunosuppressive treatment that warrants further exploration. CONCLUSIONS: In this large cohort of infliximab-treated CD patients, young age, Crohn's colitis, and concomitant immunosuppressive treatment were identified as independent variables favoring short-term response to infliximab. [less ▲]

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See detailLa fenetre implantatoire
Perrier D'Hauterive, Sophie ULg; Charlet, Jeanne de Chantal ULg; Goffin, Frédéric ULg et al

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2002), 31(5), 440-55

BACKGROUND: Embryo implantation is a complex event involving apposition followed by adhesion of the blastocyst to the maternal endometrium, and finally invasion of this endometrium. Though implantation ... [more ▼]

BACKGROUND: Embryo implantation is a complex event involving apposition followed by adhesion of the blastocyst to the maternal endometrium, and finally invasion of this endometrium. Though implantation could occur in any human tissue, the endometrium is the only tissue where embryo implantation cannot occur except during a restricted period called the implantation window. During this window, the endometrium is highly receptive to the embryo. MATERIAL: and methods. We reviewed the literature concerning the different factors involved in improved endometrial receptivity and implantation. RESULTS: Maternal - embryo crosstalk is favored by the implantation window. Endometrial receptivity results from the acquisition of ligands or receptors facilitating apposition, then adhesion of the embryo, or from the loss of components preventing it. The molecular basis of the implantation window remains to be defined. CONCLUSION: Despite progress in assisted reproduction technologies, the lack of control of implantation remains a major obstacle to successful pregnancy. It is of prime importance to determine the characteristic features of a receptive endometrium and, among the many markers proposed by in vitro studies, to analyze in humans those demonstrated by knock-out experiments to play a crucial role in mice. [less ▲]

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See detailComme Janus aux deux visages, des écrivains aux deux publics
Delbrassine, Daniel ULg

in Revue des livres pour enfants (2002), 206

Evocation des premiers résultats d'une recherche comparative sur l'écriture des auteurs mixtes (publiés en littérature de jeunesse et en littérature générale)

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See detailMultifocal serous cystadenoma of the pancreas synchronous with ampullary adenocarcinoma
Quatresooz, Pascale ULg; Honore, Pierre ULg; Vivario, M. et al

in Annales de Pathologie (2002), 22(4), 317-320

Pancreatic cysts are common, but cystic tumors are uncommon. We report a rare case of serous cystadenoma of the pancreas synchronous with ampullary adenocarcinoma which supports a common etiopathogeny of ... [more ▼]

Pancreatic cysts are common, but cystic tumors are uncommon. We report a rare case of serous cystadenoma of the pancreas synchronous with ampullary adenocarcinoma which supports a common etiopathogeny of these tumors. We discuss the differential diagnosis with mucinous cystadenoma which is potentially malignant and recall the microscopic and radiologic features. [less ▲]

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See detail5-HT2A receptor antagonism potentiates haloperidol-induced dopamine release in rat medial prefrontal cortex and inhibits that in the nucleus accumbens in a dose-dependent manner
Liégeois, Jean-François ULg; Ichikawa, J.; Meltzer, H. Y.

in Brain Research (2002), 947(2), 157-165

Combined serotonin (5-HT)(2A) and dopamine (DA) D-2 blockade has been shown to contribute to the ability of atypical antipsychotic drugs (APDs) to increase DA release in rat medial prefrontal cortex (mPFC ... [more ▼]

Combined serotonin (5-HT)(2A) and dopamine (DA) D-2 blockade has been shown to contribute to the ability of atypical antipsychotic drugs (APDs) to increase DA release in rat medial prefrontal cortex (mPFC). We provide additional support for this hypothesis by examining the effect of the selective 5-HT2A antagonist M100907 plus haloperidol, a potent D, antagonist APD, on DA release in the mPFC and nucleus accumbens (NAC). Haloperidol (0.01-1.0 mg/kg) produced an inverted U-shaped increase in DA release in the mPFC, with a significant increase only at 0.1 mg/kg. Haloperidol (0.1 and 1.0 mg/kg) significantly increased DA release in the NAC. M100907 (0.1 mg/kg) by itself had no effect on DA release in either region. This dose of M100907 potentiated the ability of low (0.01-0.1 mg/kg), but not high dose (0.3-1.0 mg/kg) haloperidol to increase mPFC DA release, whereas it abolished the effect of both 0.1 and 1.0 mg/ka haloperidol on NAC DA release. These results suggest that the relatively higher ratio of 5-HT2A to D-2 antagonism may contribute to the potentiation of haloperidol-induced mPFC DA release, whereas 5-HT2A antagonism can diminish haloperidol-induced NAC DA release, even when combined with extensive D, antagonism, which may not be synergistic with 5-HT2A antagonism in the mPFC. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailTraitement moléculaire du cancer: le STI571, un inhibiteur des tyrosines kinases
Humblet-Baron, Stéphanie ULg; Baron, Frédéric ULg; Pirson, Laurence ULg et al

in Revue Médicale Suisse (2002), 60(598), 1504-1508

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See detailAAV2 vectors mediate efficient and sustained transduction of rat embryonic ventral mesencephalon
Lehtonen, E.; Bonnaud, F.; Melas, C. et al

in Neuroreport (2002), 13(12), 1503-1507

The success of transplantation of human embryonic mesencephalic tissue to treat parkinsonian patients is limited by the poor survival of the transplant. We show that an AAV2 vector mediates efficient ... [more ▼]

The success of transplantation of human embryonic mesencephalic tissue to treat parkinsonian patients is limited by the poor survival of the transplant. We show that an AAV2 vector mediates efficient expression of the egfp reporter gene in organotypic cultures of freshly explanted solid fragments of rat embryonic ventral mesencephalon (VM). We observed early and sustained transgene expression (4 days to greater than or equal to 6 weeks). Furthermore, rAAV-infected rat embryonic VM transplanted in the adult striatum continued to express EGFP for greater than or equal to 3 months. More than 95% of the transduced cells were neurons. Dopaminergic neurons were transduced at low frequency at earlier time points. This method of gene delivery could prove useful to achieve local, continuous secretion of neurotrophic factors at physiologically relevant doses to treat Parkinson's disease. [less ▲]

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See detailOxytocin synthesis and oxytocin receptor expression by cell lines of human small cell carcinoma of the lung stimulate tumor growth through autocrine/paracrine signaling
Pequeux, Christel ULg; Breton, Christophe; Hendrick, Jean-Claude et al

in Cancer Research (2002), 62(16), 4623-4629

The objective of the present work was to investigate the existence of an oxytocin (OT)-mediated autocrine/paracrine signaling upon small cell carcinoma of the lung (SCCL) cell growth. In that view, OT ... [more ▼]

The objective of the present work was to investigate the existence of an oxytocin (OT)-mediated autocrine/paracrine signaling upon small cell carcinoma of the lung (SCCL) cell growth. In that view, OT receptor (OTR) expression, concomitant with OT synthesis and secretion, was evidenced on three different SCCL cell lines (DMS79, H146, and H345) and related to the vasopressin (VP) system. Specific OT, VP, OTR, Via VP receptor (V1aR), and V1b/V3 VP receptor (V1bR/V3R) transcripts were identified by reverse transcription-.PCR in all cell lines studied. Binding of I-125-(d(CH2)(5)(1),Tyr(Me)(2), Thr(4), Orn(3),Tyr(9)-NH2)-vasotocin (OVTA) was observed on all SCCL cell lines, with a K-d (dissociation constant) ranging from 0.025-0.089 nm, depending; on the cell line and the analytical method. Selectivity of I-125-OVTA binding was confirmed by displacement curves obtained with various OTR and VP receptor agonists and antagonists (OT, OVTA, L-371,257, VP, F180). Immunocytochemistry identified cellular OT and VP, and peptide secretion was measured in supernatants of SCCL cultures. [H-3]Thymidine incorporations, applied on H345 cells, demonstrated a dose-dependent mitogenic effect of exogenous OT (1 and 100 nM) that was abolished by the OTR antagonist OVTA. A decrease of proliferation was also observed with OVTA alone, showing a functional mitogenic effect of tumor-derived OT. Taken together, these observations demonstrate the existence of a functional OT-mediated autocrine/paracrine signaling actively implicated in growth and development of SCCL tumors. Furthermore, these findings point to the potential of OT antagonists for development as therapeutic agents for the treatment of SCCL. [less ▲]

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See detailElectrical investigations of granular arches
Dorbolo, Stéphane ULg; Vandewalle, Nicolas ULg

in Physica A: Statistical Mechanics and its Applications (2002), 311(3-4), 307-312

Compaction dynamics and granular arches have been studied using the electrical resistance of a packing. An exponential decay of the resistance is found whatever the electrical current is. A fluctuation ... [more ▼]

Compaction dynamics and granular arches have been studied using the electrical resistance of a packing. An exponential decay of the resistance is found whatever the electrical current is. A fluctuation regime is then encountered. A characteristic relaxation time has been pointed out and is linked to the arch formation in the system. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailpH Dependence of the morphology of aqueous micelles formed by polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) copolymers
Gohy, Jean-François; Willet, Nicolas ULg; Varshney, Sunil K et al

in e-Polymers (2002), (35), 1-10

The morphology of micelles formed by two polystyrene-block-poly(2-vinylpyridine)- block-poly(ethylene oxide) (PS-b-P2VP-b-PEO) copolymers was studied in water by dynamic light scattering and transmission ... [more ▼]

The morphology of micelles formed by two polystyrene-block-poly(2-vinylpyridine)- block-poly(ethylene oxide) (PS-b-P2VP-b-PEO) copolymers was studied in water by dynamic light scattering and transmission electron microscopy. Spherical micelles were observed that consist of a PS core, a P2VP shell and a PEO corona. The characteristic size of core, shell and corona depends on the copolymer composition. An important increase in micellar size occurs at pH < 5 as a result of P2VP block protonation. The reversibility of this pH effect depends on copolymer composition, too. The conformation of the PEO block plays an important role in this pH driven morphological transition. [less ▲]

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See detailHuman breast adenocarcinoma cell lines promote angiogenesis by providing cells with uPA-PAI-1 and by enhancing their expression
Bajou, Khalid ULg; Lewalle, J. M.; Martinez, C. R. et al

in International Journal of Cancer = Journal International du Cancer (2002), 100(5), 501-506

During angiogenesis, endothelial cells use uPA and PAI-I to migrate and degrade the basement membrane surrounding capillary blood vessels. Invasive tumor cells produce a large amount of uPA that could ... [more ▼]

During angiogenesis, endothelial cells use uPA and PAI-I to migrate and degrade the basement membrane surrounding capillary blood vessels. Invasive tumor cells produce a large amount of uPA that could bind uPAR present at the endothelial cell surface to facilitate their invasion. To verify this hypothesis, endothelial cells were incubated with conditioned medium (CM) from two breast cancer cell lines (MCF7 and MDA MB 231 cells). Within a short incubation period (30 min) with both CM, an increase of uPA, PAW and uPA-PAI-I complex was detected in endothelial cell layer as assessed by casein zymography, ELISA and uPA immunostaining. The extent of this enhancement was related to the levels of uPA secreted by tumor cells (high in MDA MB 231 cells and low in MCF7 cells). After 2 hr of incubation, the CM from both tumor cells upregulated uPA and PAI-I mRNA levels in endothelial cells in a time-dependent manner. The uPA increase in the cell layer could not be attributable to an increase of uPAR level. Only the CM from highly invasive MDA MB 231 cells increased the angiogenic morphotype of endothelial cells assessed in a collagen gel. A single addition of amino-terminal fragment of uPA (ATF) was able to abolish the angiogenic effect induced by MDA MB 231 cell CM. Our data demonstrate that the interactions occurring between breast tumor cells and endothelial cells can modulate tumor angiogenesis at least by two mechanisms: an increase of uPA and PAI-I cell surface-binding and of their expression by endothelial cells. (C) 2002 Wiley-Liss, Inc. [less ▲]

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See detailNovel unsaturated epsilon-caprolactone polymerizable by ring-opening and ring-opening metathesis mechanisms
Lou, Xudong; Detrembleur, Christophe ULg; Lecomte, Philippe ULg et al

in e-Polymers (2002), (34), 1-12

Ring-opening polymerization (ROP) and ring-opening metathesis polymerization (ROMP) of an unsaturated epsilon-caprolactone, 6,7-dihydro-2(3H)-oxepinone (DHO2), are alternative routes to produce ... [more ▼]

Ring-opening polymerization (ROP) and ring-opening metathesis polymerization (ROMP) of an unsaturated epsilon-caprolactone, 6,7-dihydro-2(3H)-oxepinone (DHO2), are alternative routes to produce unsaturated aliphatic polyesters with the same molecular structure. Polymerization of DHO2 initiated by Al isopropoxide in toluene at room temperature or at 0°C proceeds by a coordination-insertion mechanism, although intramolecular transesterification takes place beyond complete monomer conversion. The molecular weight distribution is narrow as long as monomer conversion does not exceed 90%. Ring-opening metathesis polymerization of DHO2 initiated by Schrock's Mo-based catalyst, 1, at 60°C allows higher molecular weight unsaturated polyester to be prepared, even though an intramolecular side reaction also operates. The structure of poly(DHO2) synthesized by ROP and ROMP is the same, as confirmed by 1H, 13C NMR, and FT-IR spectra. Copolymers of DHO2 with norbornene, cis-cyclooctene, and 1,5-cyclooctadiene have been successfully prepared. [less ▲]

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See detailSurfactant molecules intercalated in laponite as studied by C-13 and Si-29 MAS NMR
Kubies, Dana; Jérôme, Robert ULg; Grandjean, Jean ULg

in Langmuir (2002), 18(16), 6159-6163

The structure and dynamics of surfactant molecules intercalated in Laponite have been characterized by solid-state C-13 NMR relaxation times and C-13- and Si-29-detected proton relaxation times. These ... [more ▼]

The structure and dynamics of surfactant molecules intercalated in Laponite have been characterized by solid-state C-13 NMR relaxation times and C-13- and Si-29-detected proton relaxation times. These results are compared to similar data obtained for a surfactant intercalated in montmorillonite and for different mesoporous materials. As compared with montmorillonite clay, a higher mobility and a greater percentage of the gauche conformation of the surfactant molecules are found in Laponite. The Si-29-detected proton relaxation times in the rotating frame are sensitive to the amount of intercalated surfactant. [less ▲]

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See detailBulletin agrométéorologique - Juillet 2002
Tychon, Bernard ULg; Ozer, Pierre ULg; Eerens, H. et al

in Bulletin Agrométéorologique (2002)

Le mois de juillet a été caractérisé par des précipitations généralement normales à excédentaires. Les températures, la vitesse moyenne du vent et l’humidité furent proches de la normale. Par contre, le ... [more ▼]

Le mois de juillet a été caractérisé par des précipitations généralement normales à excédentaires. Les températures, la vitesse moyenne du vent et l’humidité furent proches de la normale. Par contre, le rayonnement fut médiocre sur l’ensemble du pays. Par rapport au bulletin précédent (juin 2002), les prévisions de rendement n’ont pas changé. La situation des cultures est globalement favorable, avec des rendements qui s’annoncent supérieurs voire similaires à ceux de 2001 à l’exception du colza. [less ▲]

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See detailTotal electron and proton energy input during auroral substorms: Remote sensing with IMAGE-FUV
Hubert, Benoît ULg; Gérard, Jean-Claude ULg; Evans, D. S. et al

in Journal of Geophysical Research. Space Physics (2002), 107

The IMAGE satellite carries three FUV imagers observing N[SUB]2[/SUB] LBH, O I 1356 Å, and HI Lyman alpha emissions in the polar aurora. These simultaneous observations are used to characterize the ... [more ▼]

The IMAGE satellite carries three FUV imagers observing N[SUB]2[/SUB] LBH, O I 1356 Å, and HI Lyman alpha emissions in the polar aurora. These simultaneous observations are used to characterize the precipitating electron and proton energy fluxes. The proton energy flux is derived from the Lyman alpha measurements on the basis of efficiency curves calculated with a Monte Carlo simulation of the proton aurora. The resulting proton contribution to the N[SUB]2[/SUB] LBH and O I 1356 Å emissions is calculated and subtracted to obtain the electron contribution in the other two channels. These two quantities are used to determine the precipitating electron average energy and energy flux. The proton and electron energy fluxes are integrated over the hemisphere to obtain the rate of auroral energy dissipation (hemispheric power) carried by the protons and electrons separately. The time development of the proton and electron aurora during four winter time events is examined. Although the onsets of the proton and electron aurora coincide in time and space, the time of the peak of energy dissipation and the recovery time are often found to differ. The fractional energy flux carried by the protons is highest during quiet periods and reaches a minimum during the most active phase of the substorms. This result is in agreement with the dependence of the fractional proton hemispheric power on magnetic activity measured by NOAA 15. The hemispheric power deduced from the FUV images is compared to the NOAA-deduced values and found to be in reasonable agreement. Sources of uncertainties in the determination of the hemispheric power are discussed on the basis of several sensitivity tests. In particular, it is found that the most critical factor is the assumption made on the energy of the auroral protons if this energy is <25 keV. [less ▲]

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See detailTime delay and lens redshift for the doubly imaged BAL quasar SBS 1520+530
Burud, I.; Hjorth, J.; Courbin, F. et al

in Astronomy and Astrophysics (2002), 391

We present optical R-band light curves of the gravitationally lensed quasar <ASTROBJ>SBS 1520+530</ASTROBJ> derived from data obtained at the Nordic Optical Telescope. A time delay of 130+/-3 days (1sigma ... [more ▼]

We present optical R-band light curves of the gravitationally lensed quasar <ASTROBJ>SBS 1520+530</ASTROBJ> derived from data obtained at the Nordic Optical Telescope. A time delay of 130+/-3 days (1sigma ) is determined from the light curves. In addition, spectra of <ASTROBJ>SBS 1520+530</ASTROBJ> obtained at the Keck Observatory are spatially deconvolved in order to extract the spectrum of the faint lensing galaxy, free of any contamination by the light from the bright quasar images. This spectrum indicates a lens redshift z=0.717, in agreement with one of the absorption systems found in the quasar spectra. The best mass model of the system includes a second nearby galaxy and a cluster of galaxies in addition to the main lensing galaxy. Adopting this model and an Omega =0.3, Lambda =0.7 cosmology, our time-delay measurement yields a Hubble constant of H[SUB]0[/SUB]=51 +/- 9 km s[SUP]-1[/SUP] Mpc[SUP]-1[/SUP] (1sigma error). Based on observations made with the Nordic Optical, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias and the W. M. Keck Observatory which is operated jointly by the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. Table 2 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/391/481 [less ▲]

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See detailEvidence of mast-cell activation in a subset of patients with eosinophilic chronic obstructive pulmonary disease
Louis, Renaud ULg; Cataldo, Didier ULg; Buckley, M. G. et al

in European Respiratory Journal (2002), 20(2), 325-331

Although asthma has been viewed mainly, as an eosinophilic disease, and chronic obstructive pulmonary disease (COPD) as a neutrophilic disease, recent studies have shown increased neutrophil counts in ... [more ▼]

Although asthma has been viewed mainly, as an eosinophilic disease, and chronic obstructive pulmonary disease (COPD) as a neutrophilic disease, recent studies have shown increased neutrophil counts in severe asthma and sputum eosinophilia in sonic COPD patients. In an attempt to further characterise these two syndromes according to pathology, the current authors have conducted a study of induced sputum in 15 subjects with COPD, 17 asthmatics, and 17 nonatopic healthy individuals. Sputum was analysed for cytology and levels of eosinophil cationic protein (ECP), albumin, tryptase and soluble intercellular adhesion molecule-1. The COPD subjects differed from the asthmatics as they had higher sputum neutrophil and lower columnar epithelial cell counts, but there were no differences in any soluble marker studied. When compared to control subjects, both the asthmatic and COPD subjects had raised eosinophil counts and ECP levels. In a subset of COPD subjects with Sputum eosinophilia (>3% of total cells), significantly increased levels of tryptase were detected. In conclusion, although chronic obstructive pulmonary disease is a more neutrophilic disease than asthma, the two diseases are difficult to distinguish on the basis of sputum levels of the soluble markers traditionally associated with asthma. However, a subset of patients with chronic obstructive pulmonary disease with airway eosinophilia and mast-cell activation might represent a distinct pathological phenotype. [less ▲]

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See detailHypertension artérielle et tachycardie: penser à regarder dans la pharmacie personnelle du patient
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2002), 57(8), 497-501

The case report of a young patient with an increase in blood pressure and heart rate offers the opportunity to discuss the clinical guidelines to explore and treat high blood pressure. The value of the 24 ... [more ▼]

The case report of a young patient with an increase in blood pressure and heart rate offers the opportunity to discuss the clinical guidelines to explore and treat high blood pressure. The value of the 24 h blood pressure monitoring and the need for precise information on all drugs taken are stressed. [less ▲]

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See detailEfficacy of raloxifene on vertebral fracture risk reduction in postmenopausal women with osteoporosis: Four-year results from a randomized clinical trial
Delmas, P. D.; Ensrud, K. E.; Adachi, J. D. et al

in Journal of Clinical Endocrinology and Metabolism (2002), 87(8), 3609-3617

The Multiple Outcomes of Raloxifene Evaluation trial studied 7705 postmenopausal women with osteoporosis randomized to placebo, or raloxifene 60 or 120 mg/d [JAMA 282(1999):6371. This report assesses the ... [more ▼]

The Multiple Outcomes of Raloxifene Evaluation trial studied 7705 postmenopausal women with osteoporosis randomized to placebo, or raloxifene 60 or 120 mg/d [JAMA 282(1999):6371. This report assesses the efficacy of raloxifene on the long-term cumulative incidence new vertebral fractures through 4 yr. New vertebral fractures was assessed from radiographs taken at baseline, yr 2-4. The primary analysis was the cumulative incidence of new vertebral fractures through 4 yr. A posthoc analysis compared the vertebral fracture risk in yr 4 alone with that observed in the first 3 yr. The 4-yr cumulative relative risks (RR) for one or more new vertebral fractures were 0.64 [95% confidence interval (CI) 0.53, 0.761 with raloxifene 60 mg/d and 0.57 (95% CI 0.48, 0.69) with raloxifene 120 mg/d. In yr 4 alone, raloxifene 60 mg/d reduced the new vertebral fracture risk by 39% [RR 0.61 (95% CI 0.43,0.88)], which was not found to be significantly different from the RR observed in the first 3 yr in both raloxifene groups, irrespective of prevalent fracture status. The nonvertebral fracture risk was not significantly reduced [RR 0.93 (95% CI 0.81, 1.06)]. The safety profile after 4 yr was similar to that observed after 3 yr. Raloxifene 60 and 120 mg/d through 4 yr decreased the cumulative risk of new vertebral fractures in postmenopausal women with osteoporosis. The decreased vertebral fracture risk in yr 4 alone was not different from that observed in the first 3 yr. [less ▲]

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See detailComparison between transrectal ultrasonography and pregnancy-associated glycoprotein determination for early pregnancy diagnosis in the goat
Quesada, E; Gonzalez, F; Calero, P et al

in Reproduction in Domestic Animals (2002), 37(4), 247

The aim of the present workwas to compare the efficiency of transrectal ultrasonography technique and the determination of the pregnancy-associated glycoproteins (PAG) concentrations in plasma samples for ... [more ▼]

The aim of the present workwas to compare the efficiency of transrectal ultrasonography technique and the determination of the pregnancy-associated glycoproteins (PAG) concentrations in plasma samples for pregnancy diagnosis in goats. Thirty nine Canary goats were synchronized and naturally mated every 12 hours throughout oestrous. Blood samples were collected on days 17, 18, 19, 20, 22, 24, 26 and 28 and transrectal ultrasonography was carried out on days 20, 22, 24, 26 and 28 (Day 0¼day of the last mating). PAG concentrations were analysed by a RIA method previously validated. There were 23 pregnant goats (10 single and 13 multiple pregnancies) and 16 nonpregnant goats. The pregnancy diagnosis was a little earlier by PAG determination than transrectal ultrasonography (sensitivity: 95 and 91% on Day 24 and 100 and 96% on Day 26, respectively). The ultrasonography allowed to discriminate between single and multiple pregnancies in 70% of goats (16/23) on Day 28 of pregnancy. The PAG concentrations were significantly higher in multiple than single pregnancies from Day 19 onwards, suggesting that it could also be used as a tool to discriminate between single and multiple gestations. (Supported by D.G. de Universidades del Gobierno de Canarias). [less ▲]

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See detailFluorodeoxyglucose positron emission tomography and somatostatin receptor scintigraphy for diagnosing and staging carcinoid tumours: correlations with the pathological indexes p53 and Ki-67
Belhocine, Tarik; Willems, Jacqueline ULg; Rigo, Pierre ULg et al

in Nuclear Medicine Communications (2002), 23(8), 727-734

We performed this study in order to evaluate the diagnostic accuracy of whole-body fluorodeoxyglucose positron emission tomography (FDG PET) imaging and somatostatin receptor scintigraphy (SRS) for ... [more ▼]

We performed this study in order to evaluate the diagnostic accuracy of whole-body fluorodeoxyglucose positron emission tomography (FDG PET) imaging and somatostatin receptor scintigraphy (SRS) for localizing primary carcinoid tumours and evaluating the extent of the disease. A secondary aim was to correlate those findings with the histological characteristics of the lesions. FDG PET was performed in 17 patients and SRS in 16. All patients had pathologically proven carcinoids. All lesions were verified by histopathological analysis or by follow-up. Ki-67 and p53 expression were assessed as an indicator of the tumours' aggressiveness. FDG PET correctly identified 4/7 primary tumours and 8/11 metastatic spreads, as compared to six and 10 respectively, for SRS. Most tumours were typical carcinoids with low Ki-67 expression. No correlation was found between the histological features and the tracer's uptake. We conclude that SRS remains the modality of choice for evaluating patients with carcinoid tumours, regardless of their proliferative activity. FDG PET should be reserved to patients with negative results on SRS. ((C) 2002 Lippincott Williams Wilkins). [less ▲]

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See detailElectrical resistance tomography sensor simulations: comparison with experiments
Fransolet, E.; Crine, Michel ULg; L'Homme, Guy ULg et al

in Measurement Science & Technology (2002), 13(8), 1239-1247

This paper compares experimental results (differences of potential), obtained with a 16-electrode electrical resistance tomography (ERT) device using the adjacent-electrode pair measurement strategy, with ... [more ▼]

This paper compares experimental results (differences of potential), obtained with a 16-electrode electrical resistance tomography (ERT) device using the adjacent-electrode pair measurement strategy, with finite-element method (FEM) simulations in two and three dimensions. In the first part of the paper, ERT measurements made on a homogeneous medium are compared with two- and three-dimensional FEM simulations. It is shown that the dependence of the electrical field on the axial coordinate cannot be neglected. Consequently, only the three-dimensional FEM simulations are able to fit the experimental results. In the second part of the paper, ERT measurements on static physical phantoms immersed in water evidence that ERT is significantly more sensitive to non-symmetrical distributions than to symmetrical ones. This observation is confirmed by three-dimensional FEM simulations performed on numerical phantoms that mimic the physical ones. In the last part of the paper, an attempt to use three-dimensional simulations to determine the characteristics (diameter and gas content) of a gas core created by injecting a gas flow from a single-orifice gas sparger leads to promising results. [less ▲]

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See detailL'image du mois. Faux anevrysme du ventricule gauche
LANCELLOTTI, Patrizio ULg; Melon, Pierre ULg; Grenade, Thierry ULg et al

in Revue Médicale de Liège (2002), 57(8), 485

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See detailFunctional brain imaging applications to differential diagnosis in the dementias
Salmon, Eric ULg

in Current Opinion in Neurology (2002), 15(4), 439-444

Purpose of review The diagnosis of dementia rests on an improved knowledge and a better detection of early impairments, to which functional imaging can certainly contribute. Recent findings Progress has ... [more ▼]

Purpose of review The diagnosis of dementia rests on an improved knowledge and a better detection of early impairments, to which functional imaging can certainly contribute. Recent findings Progress has been observed at different levels. First, the understanding of different dementias has benefited from explorations of the neural substrate of dementia symptoms and from research into new markers. Second, diverse variables (clinical, anatomical, biochemical) have been related to impaired cerebral activity in Alzheimer's disease and other dementias, and progress in image analysis and in multimodal data acquisition has allowed a better understanding of the significance of brain activity disturbances. Third, functional imaging has been applied in well-designed clinical studies, and has provided important arguments for the diagnosis of characteristic clinical syndromes in the dementias. Summary The functioning of neural networks responsible for clinical symptoms in dementia remains an important research topic for functional imaging. The development of new tracers and new techniques for image processing should also improve the usefulness of brain imaging as a diagnostic tool. [less ▲]

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See detailNew trends in anti-malarial agents
Frederich, Michel ULg; Dogné, Jean-Michel ULg; Angenot, Luc ULg et al

in Current Medicinal Chemistry (2002), 9(15), 1435-1456

Malaria is the major parasitic infection in many tropical and subtropical regions, leading to more than one million deaths (principally young African children) out of 400 million cases each year (WHO ... [more ▼]

Malaria is the major parasitic infection in many tropical and subtropical regions, leading to more than one million deaths (principally young African children) out of 400 million cases each year (WHO world health report 2000). More than half of the world's population live in areas where they remain at risk of malaria infection. During last years, the situation has worsened in many ways, mainly due to malarial parasites becoming increasingly resistant to several antimalarial drugs. Furthermore, the control of malaria is becoming more complicated by the parallel spread of resistance of the mosquito vector to currently available insecticides. Discovering new drugs in this field is therefore a health priority. Several new molecules are under investigation. This review describes the classical treatments of malaria and the latest discoveries in antimalarial agents, especially artemisinin and its recent derivatives as well as the novel peroxidic compounds. [less ▲]

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See detailOesophage de Barrett: mise au point
Delforge, M.; Plomteux, O.; Delfosse, Valérie ULg et al

in Revue Médicale de Liège (2002), 57(8), 535-45

Barrett's oesophagus (BE) is a segment of columnar lined epithelium in the distal oesophagus, above the gastrooesophageal junction. So it is important to localize this junction endoscopically; the ... [more ▼]

Barrett's oesophagus (BE) is a segment of columnar lined epithelium in the distal oesophagus, above the gastrooesophageal junction. So it is important to localize this junction endoscopically; the proximal margin of the gastric folds is the anatomic landmark. Another important feature of BE is the specialized intestinal metaplasia. In the aetiology of this condition, acid reflux is a primary event but there is evidence that other factors are causal. As BE is a well known premalignant condition, detection of dysplastic epithelium and its severity is the crucial element. Practical guidelines are presented for endoscopic surveillance program. The purpose is the early detection of high grade dysplasia and carcinoma to advise oesophagectomy or endoscopic ablation therapy for patients unfit to undergo surgery. [less ▲]

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See detailModulation of fibrinolytic and gelatinolytic activity during adipose tissue development in a mouse model of nutritionally induced obesity
Lijnen, Roger; Maquoi, Erik ULg; Demeulemeester, Désiré et al

in Thrombosis and Haemostasis (2002), 88(2), 345-353

A nutritionally induced obesity model was used to investigate the modulation of fibrinolytic and gelatinolytic activity during the development of adipose tissue. Five week old male mice were fed a ... [more ▼]

A nutritionally induced obesity model was used to investigate the modulation of fibrinolytic and gelatinolytic activity during the development of adipose tissue. Five week old male mice were fed a standard fat diet (SFD, 13% kcal as fat) or a high fat diet (HFD, 42% kcal as fat) for up to 15 weeks. The HFD resulted in body weights of 31 +/- 0.9 g, 38 +/- 2.0 g and 47 +/- 1.9 g at 5, 10 and 15 weeks, respectively; corresponding values for mice on the SFD were 26 +/- 0.6 g, 31 +/- 0.9 g and 31 +/- 1.2 g (all p < 0.001). The weight of the isolated subcutaneous (s.c.) or gonadal (GON) fat after 15 weeks of HFD was 1,870 +/- 180 mg or 1,470 +/- 160 mg, as compared to 250 +/- 58 mg or 350 +/- 71 mg for the SFD (p < 0.001). The HFD induced marked time-dependent hyperglycemia and elevated levels of triglycerides and total cholesterol. The HFD diet also induced a marked hypertrophy of the adipocytes as compared to the SFD, e.g. diameter of 83 +/- 3.0 microns versus 52 +/- 4.2 microns for GON adipocytes at 15 weeks (p < 0.005). Plasma plasminogen activator inhibitor-1 (PAI-1) levels were higher in mice on the HFD as compared to the SFD; they were comparable in extracts of s.c. or GON adipose tissue, whereas at different time points tissue-type (t-PA) and urokinase-type (u-PA) plasminogen activator activity was somewhat lower in the adipose tissues of mice on HFD. Gelatinolytic activity (mainly MMP-2) was detected in s.c. but not in GON adipose tissue of mice on SFD, and decreased on the HFD. In situ zymography on cryosections did not reveal different fibrinolytic activities in s.c. or GON adipose tissues of the HFD as compared to the SFD groups, whereas significantly lower gelatinolytic and higher caseinolytic activities were detected in s.c. and GON tissues of mice on the HFD (p < or = 0.05). The fibrillar collagen content was lower in adipose tissue of mice on HFD. Thus, in this model time-dependent development of adipose tissue appears to be associated with modulation of proteolytic activity. [less ▲]

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See detailImplications pathologiques du systeme neuroendocrinien digestif
Piette, Caroline ULg; Polus, Marc ULg; Louis, Edouard ULg

in Revue Médicale de Liège (2002), 57(8), 509-18

The neuroendocrine system is made of endocrine cells disseminated in various organs. In this article, we will focus on the implication of the neuroendocrine system in digestive pathology. First of all, we ... [more ▼]

The neuroendocrine system is made of endocrine cells disseminated in various organs. In this article, we will focus on the implication of the neuroendocrine system in digestive pathology. First of all, we will review the neuroendocrine tumors in every location and then describe their classification, epidemiology, symptomatology, diagnosis and treatment. Finally, we will consider the implications of the neuroendocrine system in the inflammatory and functional pathology of the digestive tract. [less ▲]

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See detailHST STIS observations of four QSO pairs
Aracil, B.; Petitjean, P.; Smette, A. et al

in Astronomy and Astrophysics (2002), 391(1), 1-12

We present HST STIS observations of four quasar pairs with redshifts 0.84<z(em)<1.56 and angular separation 2-3 arcmin corresponding to ∼1-1.5 h(50)(-1) Mpc transverse proper distance at zsimilar to0.9 ... [more ▼]

We present HST STIS observations of four quasar pairs with redshifts 0.84<z(em)<1.56 and angular separation 2-3 arcmin corresponding to ∼1-1.5 h(50)(-1) Mpc transverse proper distance at zsimilar to0.9. We study the distribution of velocity differences between nearest neighbor HI Lyman-alpha absorption lines detected in the spectra of adjacent QSOs in order to search for the possible correlation caused by the extent or the clustering properties of the structures traced by the absorption lines over such a scale. The significance of the correlation signal is determined by comparison with Monte-Carlo simulations of spectra with randomly distributed absorption lines. We find an excess of lines with a velocity separation smaller than DeltaV=500 km s(-1) significant at the 99.97% level. This clearly shows that the Lyman-alpha forest is correlated on scales larger than 1 h(50)(-1) Mpc at zsimilar to1. However, out of the 20 detected coincidences within this velocity bin, 12 have V>200 km s(-1). This probably reflects the fact that the scale probed by our observations is not related to the real size of individual absorbers but rather to large scale correlation. Statistics are too small to conclude about any difference between pairs separated by either 2 or 3 arcmin. A damped Lyman-alpha system is detected at z(abs)=1.2412 toward LBQS 0019-0145A with log N(HI)similar to20.5. From the absence of ZnII absorption, we derive a metallicity relative to solar [Zn/H]< -1.75. [less ▲]

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See detailIdentification of factors that maintain mammalian outer hair cells in adult organ of Corti explants
Malgrange, Brigitte ULg; Rigo, Jean-Michel; Coucke, Paul et al

in Hearing Research (2002), 170(1-2), 48-58

Both outer hair cells (OHCs) and inner hair cells (IHCs) survive and mature in 3 days old rat organ of Corti explants cultured for I month in a minimal essential medium. In contrast. under the same ... [more ▼]

Both outer hair cells (OHCs) and inner hair cells (IHCs) survive and mature in 3 days old rat organ of Corti explants cultured for I month in a minimal essential medium. In contrast. under the same culture conditions, only IHCs survive in explants from adult guinea pig organ of Corti while many of the OHCs are lost within the first 48 It. Hair cell Count,, show OHCs loss to be greater in the lower portion (i.e. middle turn) of the cochlea than Lit the apex. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) indicates that there is DNA damage in adult OHCs, within 8 h of explantation. Treatment of the adult organ of Corti explants with either actinomycin D (10(-7) M) or cycloheximide (10(-6) M) prevents most OHC losses . According to these results apoptosis may be the mechanism of OHC loss in adult organ of Corti explants, Stable membrane potentials recorded from the OHCs in both uncultured and actinomycin D-treated organ of Corti explants cultured for 72 h demonstrate the functional integrity of these hair cells. OHC losses in the adult guinea pig, organ of Corti cultures can also be prevented by treatment with several of the growth factors tested. i.e. acidic fibroblast growth factor (aFGF), insulin-like growth factor-1 (IGF-1), epidermal growth factor (EGF), transforming growth factor-beta1 (TGF-beta1). and glial cell-derived neurotrophic factor (GDNF). The results of this study suggest that growth factor therapy may be applicable to the treatment of some hearing disorders. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailL'etude clinique du mois. Balance benefice/risque du traitement oestroprogestatif postmenopausique en peril dans l'etude Women's Health Initiative: attitude pratique du clinicien
Gaspard, Ulysse ULg; van den Brule, F.; PINTIAUX, Axelle ULg et al

in Revue Médicale de Liège (2002), 57(8), 556-62

The Women's Health Initiative (WHI) is sponsored by the NIH. The study focuses on risk and benefits of strategies that could potentially reduce the incidence of heart disease, breast and colon cancer, and ... [more ▼]

The Women's Health Initiative (WHI) is sponsored by the NIH. The study focuses on risk and benefits of strategies that could potentially reduce the incidence of heart disease, breast and colon cancer, and fractures in postmenopausal women. One arm of the study, a double-blind, placebo-controlled trial, looking at the effects of continuous combined estrogen-progestin regimen was stopped prematurely based on health risks which exceeded health benefits. The main reason for this decision was the increase in risk of invasive breast cancer, as well as a slight increase in the rate of myocardial infarction and stroke. In this paper, we inform our colleagues of the detailed results of the study. We comment on its limitation and discuss the new original observations. Finally, we integrate the others to previous world literature data that are confirmed by the WHI study. It is important for the individual prescribing practitioner to issue practical conclusions and therapeutic recommendations. The department of Obstetrics and Gynaecologic of the University of Liege, in agreement with the European Menopause Society and the International Menopause Society, is convinced that there is no alternative to the hormone replacement therapy for menopausal symptoms. We should stick to the traditional indications for hormones, namely vasomotor symptoms and osteoporosis. We should continue to recommend hormones for symptomatic women. One should realize that the risk for breast cancer appears only after several years of use, and the risk for cardiovascular events below age 60 is very small (the age of the patients was 63 at inclusion in the WHI study). We should encourage women to take the necessary measures for routine, periodic breast examinations (both manual, echographic and radiographic). Women who use HRT for more than 5 years should discuss the latest data of the WHI study with their physician, in order to consider their individual benefit-risk equation. Those who feel good on hormones and are fully satisfied with this treatment should learn of possible harm after long-term use. It is important to take into account the importance of quality of life. We should leave to the patient the final decision whether or not to continue the treatment. It is presently impossible to decide whether other estroprogestin associations, other administration routes and other molecules such as estradiol, natural progesterone or other progestins, SERMS and Tibolone could have an impact very different from that of the estroprogestin combination used in the WHI study. It is the duty of every physician to decide, from the complex epidemiological data obtained in the aged women (63-68 years) with a high cardiovascular risk in the WHI study, if it is possible or not in each individual case to recommend the initiation or pursue of an hormone replacement therapy. [less ▲]

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See detailComparisons of two groups of sex-change applicants based on the MMPI
Michel, Aude; Ansseau, Marc ULg; Legros, Jean-Jacques ULg et al

in Psychological Reports (2002), 91(1), 233-240

Out of 29 men asking for a sex-change, 16 reported clinical anamnesis criteria for transsexualism according to the DSM-III-R, a more restrictive diagnosis than the DSM-IV gender dysphoria diagnosis. In ... [more ▼]

Out of 29 men asking for a sex-change, 16 reported clinical anamnesis criteria for transsexualism according to the DSM-III-R, a more restrictive diagnosis than the DSM-IV gender dysphoria diagnosis. In addition, all the subjects had taken an MMPI which, of course, did not contribute to the transsexualism diagnosis but which served to describe their personalities. The 16 subjects diagnosed as transsexual and the 13 who did not qualify for this diagnosis were compared on the basis of personality variables measured by the MMPI. Certain differences became evident. The transsexuals systematically complied to cultural stereotypes of femininity without any uneasiness, whereas the nontranssexuals could be subdivided into two groups, those with a vague sense of ill-being linked to a pronounced feminine identity or those with only a slight feminine identity and who showed no particular difficulties. [less ▲]

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See detailEffectiveness of bioremediation of crude oil contaminated subantarctic intertidal sediment: The microbial response
Delille, D.; Delille, Bruno ULg; Pelletier, E.

in Microbial Ecology (2002), 44(2), 118-126

A field study was initiated in February 1996 in a remote sandy beach of The Grande Terre (Kerguelen Archipelago, 69degrees 42' E, 49degrees 19' S) with the objective of determining the long-term effects ... [more ▼]

A field study was initiated in February 1996 in a remote sandy beach of The Grande Terre (Kerguelen Archipelago, 69degrees 42' E, 49degrees 19' S) with the objective of determining the long-term effects of some bioremediation agents on the biodegradation rate and the toxicity of oil residues under severe subantarctic conditions. A series of 10 experimental plots were settled firmly into sediment. Each plot received 2L of Arabian light crude oil and some of them were treated with bioremediation agents: slow release fertilizer Inipol EAP-22 (Elf Atochem) or fish composts. Plots were sampled on a regular basis over a 3-year period. A two-order of magnitude increase of saprophytic and hydrocarbon-utilizing microorganisms occurred during the first month of the experiment in all treated enclosures, but no clear differences appeared between the plots. Very high microbial populations were present during the experiment. Biodegradation within treated spots was faster than within the untreated ones and appeared almost complete after 6 months as indicated by the degradation index of aliphatic hydrocarbons within all plots. The analysis of interstitial water collected below the oily residues presented no toxicity. However, a high toxicity signal, using Microtox solid phase, appeared for all oiled sand samples with a noticeable reduction with time even if the toxicity signal remained present and strong after 311 days of oil exposition. As a conclusion, it is clear that the microbial response was rapid and efficient in spite of the severe weather conditions, and the rate of degradation was improved in presence of bioremediation agents. However, the remaining residues had a relatively high toxicity. [less ▲]

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See detailStrictureplasty in Crohn's disease : Short- and long-term follow-up
Laurent, Stanislas; Detry, Olivier ULg; Detroz, Bernard ULg et al

in Acta Chirurgica Belgica (2002), 102(4, JUL-AUG), 253-255

Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection ... [more ▼]

Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection, hoping for fewer complications and a lower recurrence rate. In this paper, the authors reports their strictureplasty experience. They performed a systematic retrospective review of the patients suffering from Crohn's disease who underwent strictureplasties during a 10-year period in the abdominal surgery department of the University Hospital of Liege Sart Tilman, and studied the short- and long-term clinical results of 68 strictureplasties performed in 18 patients. Median follow-up was 63 months (range 12 to 144). Mortality was 0% and septic morbidity was 11% (one wound abscess and one leakage). Among the 16 patients available for the latest follow-up, symptomatic stenotic recurrence had to be medically treated in hospital for 4 patients (25%) with a recurrence delay range of 19 to 49 months. Stenosis recurrence needed re-intervention in one patient 48 months after surgery: stenosis occurred at a distance from the corrected site. These results confirmed that strictureplasty is a safe and efficient procedure in selected patients undergoing surgery for obstructive Crohn's disease. [less ▲]

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See detailMatrix metalloproteinase-9 deficiency impairs cellular infiltration and bronchial hyperresponsiveness during allergen-induced airway inflammation
Cataldo, Didier ULg; Tournoy, K. G.; Vermaelen, K. et al

in American Journal of Pathology (2002), 161(2), 491-498

We investigated the specific role of matrix metalloproteinase (MMP)-9 in allergic asthma using a murine model of allergen-induced airway inflammation and airway hyperresponsiveness in MMP-9(-/-) mice and ... [more ▼]

We investigated the specific role of matrix metalloproteinase (MMP)-9 in allergic asthma using a murine model of allergen-induced airway inflammation and airway hyperresponsiveness in MMP-9(-/-) mice and their corresponding wild-type (WT) littermates. After a single intraperitoneal sensitization to ovalbumin, the mice were exposed daily either to ovalbumin (1%) or phosphate-buffered saline aerosols from days 14 to 21. Significantly less peribronchial mononuclear cell infiltration of the airways and less lymphocytes in the bronchoalveolar lavage fluid were detected in challenged MMP-9(-/-) as compared to WT mice. In contrast, comparable numbers of bronchoalveolar lavage fluid eosinophils; were observed in both genotypes. After allergen exposure, the WT mice developed a significant airway hyperresponsiveness to carbachol whereas the MMP-9(-/-) mice failed to do so. Allergen exposure induced an increase of MMP-9-related gelatinolytic activity in WT lung extracts. Quantitative reverse transcriptase-polymerase chain reaction showed increased mRNA levels of MMP-12, MMP-14, and urokinase-type plasminogen activator after allergen exposure in the lung extracts of WT mice but not in MMP-9-deficient mice. in contrast, the expression of tissue inhibitor of metalloproteinases-1 was enhanced after allergen exposure in both groups. We conclude that MMP-9 plays a key role in the development of airway inflammation after allergenexposure. [less ▲]

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See detailPAG profiles in postpartum dairy cows and newborn calves
Ropstad, E; Kalberg, K; Dahl, E et al

in Reproduction in Domestic Animals (2002), 37(4), 249

In ruminants, pregnancy associated glycoproteins (PAG), synthesized in the outer layers of the trophoblast, enter the maternal bloodstream. In this study, blood samples from cows in the postpartum period ... [more ▼]

In ruminants, pregnancy associated glycoproteins (PAG), synthesized in the outer layers of the trophoblast, enter the maternal bloodstream. In this study, blood samples from cows in the postpartum period, pregnant cows and calves were collected to determine 1) the clearance rate of PAG, 2) the accuracy of PAG measurements used for pregnancy diagnosis and 3) PAG concentrations and clearance rate in newborn calves. A curvilinear decline in PAG was found with increasing days from calving. Between day 70–80 pp 3 out of 11 samples (27%) had PAG concentrations > 4 ng/ml plasma. A cut-off value of 4 ng/ml was found to give the best accuracy for pregnancy diagnosis 28–36 days after service (n ¼58: sensitivity¼0.97; specificity ¼1.0). PAG concentrations in newborn calves (n¼10) varied between 78–880 ng/ml, declining with increasing age in a curvilinear pattern to < 1 ng/ml between 20–40 days pp. In two male twin calves PAG concentrations were 880 and 101 ng/ml, respectively, at one day of age. We conclude: 1) 4 ng PAG /ml provides the best cut-off value for pregnancy diagnosis. 2) Cows serviced before 60 days pp can produce false positive pregnancy diagnoses due to PAG originating from the previous pregnancy. 3) High PAG concentrations can be found in newborn calves. [less ▲]

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See detailTrace element and isotope (Sr, Nd) geochemistry of porphyry- and skarn-mineralising Late Cretaceous intrusions from Banat, western South Carpathians, Romania
Dupont, Alain; Vander Auwera, Jacqueline ULg; Pin, Christian et al

in Mineralium Deposita (2002), 37(6-7), 568-586

Geochemical and isotopic (strontium, neodymium) data have been obtained from 24 samples of seven Late Cretaceous intrusions associated with skarn (Tincova, Bocsa, Ocna de Fier - Dognecea) and porphyry ... [more ▼]

Geochemical and isotopic (strontium, neodymium) data have been obtained from 24 samples of seven Late Cretaceous intrusions associated with skarn (Tincova, Bocsa, Ocna de Fier - Dognecea) and porphyry copper-molybdenum/skarn deposits (Oravita, Ciclova, Sasca and Moldova Noua) in the South Carpathians of Romania. The intrusions cut the Supragetic-Getic nappes and form a 100-km-long, NNE-SSW-trending lineament in the Banat metallogenic province. The samples range in composition from gabbro to granodiorite and define, in major and trace element variation diagrams, a calc-alkaline to high-potassium calc-alkaline trend ranging from 50 to 67% SiO2. They are magnetite-bearing, I-type granitoids enriched in LILE/LREE and depleted in Nb, Ta and Zr, common features for magmas associated with subduction zones. The lack of cumulate textures and of positive europium anomalies seems to indicate that the samples represent liquid compositions. The observed trend thus approximates a liquid line of descent resulting from fractional crystallisation of parental magmas with similar major and trace element compositions. Initial strontium isotopic ratios (Sr-i) vary from 0.7042 to 0.7058 and epsilon(Nd(t)) values range from + 3.9 to -0.2. Variations of Sri and epsilon(Nd(t)) values with SiO2 show minor crustal assimilation. The generally positive epsilon(Nd(t)) values, together with moderate Sri, indicate that the parental magmas result from partial melting of a rubidium-enriched and LREE-depleted source, such as a heterogeneous lithospheric mantle or a young mafic lower crust derived from it. Selective rubidium enrichment probably occurred during a previous subduction event by metasomatism of the overlying mantle wedge, either in the Early Cretaceous or earlier, as suggested by T-DM model ages (ca. 600 Ma). The Cu-Mo(-Pb-Zn-Fe) deposits are intimately associated with the intrusions, and the Banat (Romania) region can be subdivided in two metallogenic zones. In northern Banat, Fe-Cu-Pb-Zn skarns occur whereas in southern Banat, porphyry-style copper and molybdenum deposits predominate. These differences result from a combination of several parameters: (1) magma composition, whereby copper- and molybdenum-rich deposits tend to be associated with calc-alkaline compositions; (2) an increase of the present-day erosion level, from south to north, as indicated by the presence of large equigranular plutons in northern Banat, and of porphyritic cupolas and apophyses associated with porphyry-style mineralisation in southern Banat; (3) the nature of the host rocks, with skarns preferentially developed in calcareous host rocks; and (4) local variations of conditions controlling the infiltration of fluids and the precipitation of ore minerals. [less ▲]

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See detailThe beneficial role of different auxins and polyamines at successive stages of somatic embryo formation and development of Panax ginseng in vitro
Kevers, Claire ULg; Gaspar, Thomas ULg; Dommes, Jacques ULg

in Plant Cell, Tissue & Organ Culture (2002), 70(2), 181-188

The production of viable plantlets via somatic embryogenesis in Panax ginseng requires different culture media corresponding to successive developmental stages. The effects of several auxins and ... [more ▼]

The production of viable plantlets via somatic embryogenesis in Panax ginseng requires different culture media corresponding to successive developmental stages. The effects of several auxins and polyamines have been tested at various steps. Multiplication of the embryogenic root-derived callus has been optimized on half-strength MS medium supplemented with 3-(benzo[b]selenyl)acetic acid (BSAA, a synthetic auxin) and kinetin; exogenously applied polyamines were deleterious at this stage, causing browning of the callus, diminished capacity of embryo initiation, and an increased tendency to hyperhydricity. BSAA again appeared to be the most favourable auxin at the initiation stage, but here its action was reinforced by the presence of polyamines, spermidine being the most efficient. Among the auxin needed at the next step, i.e., for the regeneration of embryos, the two seleniated auxins BSAA and seleniated 2,4-dichlorophenoxyacetic acid (2,4-D-Se) were the more efficient. For the harmonious development of plantlets, i.e., the simultaneous outgrowth of shoots and roots, the polyamines were favourable, with a greater efficiency for spermine. [less ▲]

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See detailMolecular basis of cold adaptation
D'Amico, Salvino ULg; Claverie, P.; Collins, T. et al

in Philosophical Transactions of the Royal Society of London Series B-Biological Sciences (2002), 357(1423), 917-924

Cold-adapted, or psychrophilic, organisms are able to thrive at low temperatures in permanently cold environments, which in fact characterize the greatest proportion of our planet. Psychrophiles include ... [more ▼]

Cold-adapted, or psychrophilic, organisms are able to thrive at low temperatures in permanently cold environments, which in fact characterize the greatest proportion of our planet. Psychrophiles include both prokaryotic and eukaryotic organisms and thus represent a significant proportion of the living world. These organisms produce cold-evolved enzymes that are partially able to cope with the reduction in chemical reaction rates induced by low temperatures. As a rule, cold-active enzymes display a high catalytic efficiency, associated however, with a low thermal stability. In most cases, the adaptation to cold is achieved through a reduction in the activation energy that possibly originates from an increased flexibility of either a selected area or of the overall protein structure. This enhanced plasticity seems in turn to be induced by the weak thermal stability of psychrophilic enzymes. The adaptation strategies are beginning to be understood thanks to recent advances in the elucidation of the molecular characteristics of cold-adapted enzymes derived from X-ray crystallography, protein engineering and biophysical methods. Psychrophilic organisms and their enzymes have, in recent years, increasingly attracted the attention of the scientific community due to their peculiar properties that render them particularly useful in investigating the possible relationship existing between stability, flexibility and specific activity and as valuable tools for biotechnological purposes. [less ▲]

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See detailHysteretic behavior in metallic granular matter
Dorbolo, Stéphane ULg; Ausloos, Marcel ULg; Vandewalle, Nicolas ULg

in Applied Physics Letters (2002), 81(5), 936-938

Various packings made of metallic grains have been electrically characterized. Electrical breakdown is observed in I-V curves. A well defined critical point separates the insulating and the conducting ... [more ▼]

Various packings made of metallic grains have been electrically characterized. Electrical breakdown is observed in I-V curves. A well defined critical point separates the insulating and the conducting regime of the packing. The breakdown is reversible by submitting the packing to a small tap. This unusual property leads to hysteretic loops in I-V diagrams. The study of the behavior of I-V curves allows us to describe the system as a network of weak lossy contacts. The key parameter is the inner electrical field controlling the diode-like or diffusion-like state of the packing. (C) 2002 American Institute of Physics. [less ▲]

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See detailNon-linear generalization of principal component analysis: From a global to a local approach
Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg

in Journal of Sound & Vibration (2002), 254(5), 867-876

Principal component analysis (PCA), also known as proper orthogonal decomposition or Karhunen-Loeve transform, is commonly used to reduce the dimensionality of a data set with a large number of ... [more ▼]

Principal component analysis (PCA), also known as proper orthogonal decomposition or Karhunen-Loeve transform, is commonly used to reduce the dimensionality of a data set with a large number of interdependent variables. PCA is the optimal linear transformation with respect to minimizing the mean square reconstruction error but it only considers second-order statistics. If the data have non-linear dependencies, an important issue is to develop a technique which takes higher order statistics into account and which can eliminate dependencies not removed by PCA. Recognizing the shortcomings of PCA, researchers in the field of statistics and neural networks have developed non-linear extensions of PCA. The purpose of this paper is to present a non-linear generalization of PCA, called VQPCA. This algorithm builds local linear models by combining PCA with clustering of the input space. This paper concludes by observing from two illustrative examples that VQPCA is potentially a more effective tool than conventional PCA. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailAnnual nitrogen budget of the seagrass Posidonia oceanica as determined by in situ uptake experiments
Lepoint, Gilles ULg; Millet, S.; Dauby, Patrick ULg et al

in Marine Ecology. Progress Series (2002), 237

The uptake of nitrate and ammonium by the roots and leaves of Posidonia oceanica were determined between February 1993 and June 1999 by in situ experiments using the isotope 15 of nitrogen (N-15) as a ... [more ▼]

The uptake of nitrate and ammonium by the roots and leaves of Posidonia oceanica were determined between February 1993 and June 1999 by in situ experiments using the isotope 15 of nitrogen (N-15) as a tracer in a nutrient-poor coastal zone of the NW Mediterranean Sea (Revellata Bay, Corsica). Nitrate and ammonium leaf uptakes are recorded at 0.05 and 0.1 muM respectively. The high variability observed cannot be explained solely by the variation of the substrate concentrations in the water column. For leaves, mean specific uptake rates were 43 +/- 45 and 43 +/- 64 mug N g N-1 h(-1). Nitrate and ammonium leaf uptake fluxes (g N m(-2) yr(-1)) seem to have the same importance on an annual basis. :Nitrate uptake occurs mainly in winter and early spring, when nitrate concentrations in the water column are highest. The uptake of N, and mainly of ammonium, is significant throughout the year with maxima at the beginning of spring, but it is insufficient to meet the annual N requirement of the plant. Posidonia root biomass was very high and corresponded to high specific N uptake rates by the roots. Ammonium was incorporated by the roots 6 times faster than nitrate. In the sediment, this uptake capacity is limited by the nutrient diffusion rate, and the root uptake is therefore insufficient to meet the N requirements of the plant. In fact, P. oceanica of Revellata Bay have a complex N budget involving uptake and recycling processes and allowing the plants to meet their N requirements in one of the most nutrient-poor areas of the NW Mediterranean Sea. We calculated that leaf and root would contribute to 40 and 60% of the annual N uptake, respectively, and 60% of the annual N requirement of the plant. [less ▲]

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See detailNoradrenergic control of auditory information processing in female canaries
Appeltants, D.; Del Negro, C.; Balthazart, Jacques ULg

in Behavioural Brain Research (2002), 133(2), 221-235

An ethological procedure, based on the study of the sexual responsiveness of female canaries (Serinus canaria) to song playbacks was used to investigate the function of central noradrenergic inputs in the ... [more ▼]

An ethological procedure, based on the study of the sexual responsiveness of female canaries (Serinus canaria) to song playbacks was used to investigate the function of central noradrenergic inputs in the processing of auditory information. The effects of a noradrenergic denervation on sexual responses was analyzed in females exposed to playbacks of biological relevant auditory stimuli, i.e. sexually stimulating songs, presented alone or masked by auditory distractors. A decrease in behavioral responsiveness was observed as a function of the amount of masking distractors indicating that female canaries have the perceptual ability to discriminate and selectively attend to biologically relevant songs. After the systemic administration of DSP-4, a specific noradrenergic neurotoxin, females exhibited an overall decrease in sexual responsiveness to songs masked or not by distractors. No effect of DSP-4 were detected on the motor activity nor on reproductive behaviors. These results indicate that central noradrenergic inputs modulate the sexual behavior of female canaries by affecting the auditory processing of relevant information contained in sexually stimulating songs. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailControlled synthesis and chemical modification of unsaturated aliphatic (co)polyesters based on 6,7-dihydro-2(3H)-oxepinone
Lou, Xudong; Detrembleur, Christophe ULg; Lecomte, Philippe ULg et al

in Journal of Polymer Science. Part A, Polymer Chemistry (2002), 40(14), 2286-2297

A pure unsaturated cyclic ester, 6,7-dihydro-2(3H)-oxepinone (DHO2), was prepared by a new synthetic route. The copolymerization of DHO2 with epsilon-caprolactone (CL) was initiated by aluminum ... [more ▼]

A pure unsaturated cyclic ester, 6,7-dihydro-2(3H)-oxepinone (DHO2), was prepared by a new synthetic route. The copolymerization of DHO2 with epsilon-caprolactone (CL) was initiated by aluminum isopropoxide [Al(OiPr)3] at 0 °C as an easy way to produce unsaturated aliphatic polyesters with nonconjugated CC double bonds in a controlled manner. The chain growth was living, as certified by the agreement between the experimental molecular weight at total monomer conversion and the value predicted from the initial monomer/initiator molar ratio. The polydispersity was reasonably low (weight-average molecular weight/number-average molecular weight 1.2). The homopolymerization of DHO2 was, however, not controlled because of fast intramolecular transesterification. Copolymers of DHO2 and CL were quantitatively oxidized with the formation of epoxides containing chains. The extent of the epoxidation allowed the thermal properties and thermal stability of the copolyesters to be modulated. The epoxidized copolyesters were successfully converted into thioaminated chains, which were then quaternized into polycations. No degradation occurred during the chemical modification. [less ▲]

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See detailStratospheric HF column abundances above Kitt Peak (31.9 degrees N latitude): trends from 1977 to 2001 and correlations with stratospheric HCl columns
Rinsland, Curtis P.; Zander, Rodolphe ULg; Mahieu, Emmanuel ULg et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2002), 74(2), 205-216

Time series of stratospheric hydrogen fluoride (HF) column abundances have been derived from infrared solar absorption spectra recorded for 195 days between May 1977 and June 2001 at a spectral resolution ... [more ▼]

Time series of stratospheric hydrogen fluoride (HF) column abundances have been derived from infrared solar absorption spectra recorded for 195 days between May 1977 and June 2001 at a spectral resolution of typically 0.01 cm(-1). The measurements were made at the US National Solar Observatory facility on Kitt Peak, Arizona, USA (31.9degreesN, 111.6degreesW, 2.09 km altitude) and have been analyzed with the SFIT2 algorithm, which is based on a semi-empirical application of the optimal estimation method. The measurements show a continuous buildup of the stratospheric HF column over the 24-yr period superimposed on short-term variations and a seasonal cycle with spring maxima and autumn minima. The measured stratospheric HF columns increased by a factor of 4.7, from 2.03 x 10(14) molecule cm(-2) in May 1977 to 9.49 x 10(14) molecule cm(-2) in June 2001. A best fit with a model that assumes an exponential increase in the stratospheric HF column with time superimposed on a sinusoidal seasonal cycle yields an average rate of stratospheric HF column increase of (4.30 +/- 0.15% yr(-1)), 1 sigma. The rate of increase is nearly a factor of two less than that derived previously from 1977 to 1990 Kitt Peak total columns, which indicates a significant slowdown in the increase rate during the 1990s, consistent with the trends from recent near-global lower mesospheric satellite remote and surface in situ measurements. Day-to-day stratospheric HIT columns are highly correlated with the same day stratospheric HCl columns as a result of common transport of lower and higher latitude air to above the station. Extrapolation of the linear relation between the two sets of stratospheric columns indicates a background HCl column of 1 x 10(15) molecule cm(-2) for zero HF, consistent with a previous estimate from 1977 to 1990 HF and HCl Kitt Peak total column measurements and a 1973 HCl measurement above the station. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailPattern recognition with a digital holographic microscope working in partially coherent illumination
Dubois, Frank; Minetti, Christophe; Monnom, Olivier et al

in Applied Optics (2002), 41(20), 4108-4119

We describe the implementation of the automatic spatial-frequency-selection filter for recognition of patterns obtained with a digital holographic microscope working with a partially coherent source. The ... [more ▼]

We describe the implementation of the automatic spatial-frequency-selection filter for recognition of patterns obtained with a digital holographic microscope working with a partially coherent source. The microscope provides the complex-optical-amplitude field that allows a refocusing plane-by-plane of the sample under investigation by numerical computation of the optical propagation. By inserting a correlation filter in the propagation equation, the correlation between the filter and the propagated optical field is obtained. In this way, the pattern is located in the direction of the optical axis. Owing to the very weak noise level generated by the partially coherent source, the correlation process is shift invariant. Therefore the samples can be located in the three dimensions. To have a robust recognition process, a generalized version of the automatic spatial-frequency-selection filters has been implemented. The method is experimentally demonstrated in a two-class problem for the recognition of protein crystals. (C) 2002 Optical Society of America. [less ▲]

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See detailCumulative reaction probability by constrained dynamics: H transfer in HCN, H2CO, and H3CO
Baloitcha, Ezinvi; Lasorne, Benjamin; Lauvergnat, David et al

in Journal of Chemical Physics (2002), 117(2), 727-739

A strategy to obtain quantum corrections to the cumulative reaction probability from a subspace of active coordinates is analyzed. The kinetic energy operator exactly takes into account the constraints ... [more ▼]

A strategy to obtain quantum corrections to the cumulative reaction probability from a subspace of active coordinates is analyzed. The kinetic energy operator exactly takes into account the constraints due to inactive coordinates. The geometry of the inactive skeleton is adiabatically adjusted to the dynamical variables or simply frozen according to the coupling to the active space. Dynamics is carried out using the curvilinear coordinates of the Z-matrix so that computation of the potential energy surface and dynamics are coupled. The cumulative reaction probability N(E) is obtained directly in a large range of energy by a time independent formulation of the Zhang and Light transition state wave packet method. N-nD(E) is first computed in the active n-dimensional space and then convoluted with a bath. The efficiency of the Chebyshev expansion of the microcanonical projection operator delta(E-(H) over cap (nD)) appearing in the quantum expression of N-nD(E) is checked. The method is implemented for the study of tunneling effect in H transfer. The coordinates are three spherical coordinates referred to the frozen or adiabatic skeleton. We compare the quantum corrections brought about by different 2D groups of internal coordinates. (C) 2002 American Institute of Physics. [less ▲]

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See detailDifferential production of cytokines and activation of NF-kappa B in HPV-transformed keratinocytes
Havard, L.; Delvenne, Philippe ULg; Frare, P. et al

in Virology (2002), 298(2), 271-285

We have proposed that chronic infection of keratinocytes by HPV modifies the expression of potentially important cytokines by interfering with the NF-kappaB signal pathway We evaluated the constitutive ... [more ▼]

We have proposed that chronic infection of keratinocytes by HPV modifies the expression of potentially important cytokines by interfering with the NF-kappaB signal pathway We evaluated the constitutive and IL-1beta-induced expression of GM-CSF and TNF-alpha and the expression/activity of NF-kappaB in HPV+ and HPV- cell lines. Despite the enhanced expression of the functional components of the NF-kappaB signaling pathway in HPV+ cell lines by a mechanism implicating the HPV oncoprotein E6, the constitutive activity of NF-kappaB and the expression of GM-CSF/TNF-alpha were significantly reduced relative to the HPV- cell line and normal keratinocytes. In contrast, we observed a superactivation of NF-kappaB activity after IL-1beta stimulation, a strong and transient induction of GM-CSF/TNF-alpha mRNA, but undetectable levels of secreted proteins in HPV+ cell lines. Our data demonstrate that E6 modulates the NF-kappaB signaling pathway and suggest that other HPV proteins also interfere with GM-CSF/TNF-alpha expression by transcriptional and/or posttranscriptional mechanisms. (C) 2002 Elsevier Science (USA). [less ▲]

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See detailSubstrate-activated zinc binding of metallo-beta-lactamases - Physiological importance of the mononuclear enzymes
Wommer, S.; Rival, S.; Heinz, U. et al

in Journal of Biological Chemistry (2002), 277(27), 24142-24147

We have investigated the influence of substrate binding on the zinc ion affinity of representatives from the three metallo-g-lactamase subclasses, B1 (BcII from Bacillus cereus and BlaB from ... [more ▼]

We have investigated the influence of substrate binding on the zinc ion affinity of representatives from the three metallo-g-lactamase subclasses, B1 (BcII from Bacillus cereus and BlaB from Chryseobacterium meningosepticum), B2 (CphA from Aeromonas hydrophila), and B3 (L1 from Stenotrophomonas maltophilia). By competition experiments with metal-free apoenzymes and chromophoric zinc chelators or EDTA, we determined the dissociation constants in the absence and presence of substrates. For the formation of the monozine enzymes we determined constants of 1.8, 5.1, 0.007, and 2.6 nm in the absence and 13.6, 1.8, 1.2, and 5.7 pm in the presence of substrates for Bell, BlaB, CphA, and L1, respectively. A second zinc ion binds in the absence (presence) of substrates with considerably higher dissociation constants, namely 1.8 (0.8), 0.007 (0.025), 50 (1.9), and 0.006 (0.12) mum for BcII, BlaB, CphA, and L1, respectively. We have concluded that the apo form might be the prevailing state of most of the metallo-beta-lactamases under physiological conditions in the absence of substrates. Substrate availability induces a spontaneous self-activation due to a drastic decrease of the dissociation constants, resulting in the formation of active mononuclear enzymes already at picomolar free zinc ion concentrations. In the presence of substrates, the binuclear state of the enzymes only exists at unphysiologic high zinc concentrations and might be of no biological relevance. From the competition experiments with EDTA it is further concluded that the reactivation rate does not depend on the pool of free zinc ions but proceeds via the EDTA-Zn(II)-enzyme ternary complexes. [less ▲]

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See detailBulletin agrométéorologique - Juin 2002
Tychon, Bernard ULg; Ozer, Pierre ULg; Eerens, H. et al

in Bulletin Agrométéorologique (2002)

Le mois de juin a été caractérisé par des précipitations généralement normales à déficitaires dans l’Est et le Sud du pays. Les températures furent supérieures à la moyenne. Les autres paramètres ... [more ▼]

Le mois de juin a été caractérisé par des précipitations généralement normales à déficitaires dans l’Est et le Sud du pays. Les températures furent supérieures à la moyenne. Les autres paramètres météorologiques étaient proches de la normale. Par rapport au bulletin précédent (mai 2002), les prévisions de rendement n’ont pas changé. La situation des cultures est globalement favorable, avec des rendements qui s’annoncent supérieurs à ceux de 2001 à la possible exception du colza et du maïs fourrager. [less ▲]

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See detailProton aurora in the cusp
Frey, H. U.; Mende, S. B.; Immel, T. J. et al

in Journal of Geophysical Research. Space Physics (2002), 107

Frequently, the Far Ultraviolet Instrument (FUV) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft observes intense ultraviolet emission from a localized dayside region ... [more ▼]

Frequently, the Far Ultraviolet Instrument (FUV) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft observes intense ultraviolet emission from a localized dayside region poleward of the general auroral oval location. This emission is especially distinct in the Doppler-shifted emission of hydrogen atoms produced by precipitating protons. We interpret this as a direct signature of proton precipitation into the cusp after reconnection of magnetospheric lobe field lines. This cusp signature appears only when the interplanetary magnetic field (IMF) has a positive northward B[SUB]z[/SUB] component. However, the intensity of the precipitation, and hence the intensity of UV emission, is not controlled by the magnitude of B[SUB]z[/SUB] but rather by the solar wind dynamic pressure. A statistical analysis of 18 cases observed in summer and fall 2000 shows good correlation between the UV intensity and the dynamic pressure and between the location in local time and the IMF B[SUB]y[/SUB] component. A quantitative analysis of observations from all three FUV subinstruments allows for an estimate of proton and electron energy fluxes during these times. In general, these estimates agree with results from in situ measurements by spacecraft and show that during these times, protons may contribute significantly to the overall energy deposition into the cusp. [less ▲]

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See detailTransient modifications of respiratory capacity in thymic cells during murine radioleukemogenesis
Verlaet, Myriam ULg; Duyckaerts, Claire ULg; Rahmouni, Souad ULg et al

in Free Radical Biology & Medicine (2002), 33(1), 76-82

The evolution of mitochondrial oxidative phosphorylation was studied during cancer induction in a model of thymic radiolymphomagenesis in C57BL/Ka mice. During the preneoplastic period, thymuses displayed ... [more ▼]

The evolution of mitochondrial oxidative phosphorylation was studied during cancer induction in a model of thymic radiolymphomagenesis in C57BL/Ka mice. During the preneoplastic period, thymuses displayed an increase of the cytochrome c oxidase activity and oxygen consumption together with oxidative DNA damage assessed by the presence of the 8-hydroxydeoxyguanine DNA base modification. These transient changes in mitochondrial functional activity were not observed in thymuses of mice rescued from lymphoma development by a bone marrow graft, suggesting an important role of mitochondria for neoplastic transformation in this model. which might therefore be of interest to test the utilization of antioxidants for the prevention of radiation-induced malignancies. (C) 2002 Elsevier Science Inc. [less ▲]

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See detailExperimental study of cracking induced by desiccation in 1-dimensional systems
Lecocq, N.; Vandewalle, Nicolas ULg

in European Physical Journal E -- Soft Matter (2002), 8(4), 445-452

We designed a simple experiment to study both the dynamical and statistical properties of cracking that occurs in a one-dimensional system composed of wet clay (or similar material) exposed to shrinkage ... [more ▼]

We designed a simple experiment to study both the dynamical and statistical properties of cracking that occurs in a one-dimensional system composed of wet clay (or similar material) exposed to shrinkage induced by desiccation. We study both the dynamical formation of cracks and the statistical characteristics of the final cracks pattern. We observe that the drying rate has a strong influence on the way cracks appear and grow. We find that the final crack width is related to the order of apparition of the cracks. We discuss the statistical distributions of cracks width and separation between two adjacent cracks. We also study the correlations between these two quantities. Our results are compared to the predictions of existing models. Finally, a comparison with another kind of clay is made. [less ▲]

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See detailSources of Labrador Sea sediments since the last glacial maximum inferred from Nd-Pb isotopes
Fagel, Nathalie ULg; Innocent, Christophe; Gariepy, Clément et al

in Geochimica et Cosmochimica Acta (2002), 66(14), 2569-2581

Pb isotopes have been measured in the clay-size fraction of Late Glacial and Holocene deep-sea sediments recovered from two Labrador Sea piston cores that have been previously analyzed for Nd isotopes ... [more ▼]

Pb isotopes have been measured in the clay-size fraction of Late Glacial and Holocene deep-sea sediments recovered from two Labrador Sea piston cores that have been previously analyzed for Nd isotopes. The newly acquired Pb isotopic data allow us to better constrain the different source areas that supplied clay-size material during the last deglaciation, until 8.6 kyr (calendar ages). Nd-Pb data can be modeled mainly as a mixture between a Precambrian crust and Lower Palcozoic material originating from the denudation of the pan-African orogen. The old material originates mainly from the Archean, Lower Proterozoic, or both terranes of Greenland (and also probably corresponding terranes of Labrador), although minor input of other Precambrian material is recorded in some detrital carbonate-rich deglacial samples from Orphan Knoll. The Phanerozoic crustal end member consists of sediment material mainly originating from northwestern Europe. This source area is found to be the only significant source of young crustal material in early Holocene sediments from the Greenland Rise. No significant input from the mid-Atlantic volcanism is apparent. This study puts further constraints on the deep circulation pattern during the last deglaciation. It is concluded that at that time, European Phanerozoic material was carried from the Norwegian Sea through the Wyville Thompson Ridge into the Iceland Basin by the North East Atlantic Deep Water. No evidence for an overflow is found either south of the Iceland (Iceland-Scotland Ridge) or through the Denmark Strait. Copyright (C) 2002 Elsevier Science Inc. [less ▲]

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See detailA positive response to infliximab in Crohn disease: Association with a higher systemic inflammation before treatment but not with-308 TNF gene polymorphism
Louis, Edouard ULg; Vermeire, S.; Rutgeerts, P. et al

in Scandinavian Journal of Gastroenterology (2002), 37(7), 818-824

Background: Two-thirds to three-fourths of patients with either refractory luminal or fistulizing Crohn disease respond to infliximab treatment. The ability or inability to respond seems to persist over ... [more ▼]

Background: Two-thirds to three-fourths of patients with either refractory luminal or fistulizing Crohn disease respond to infliximab treatment. The ability or inability to respond seems to persist over time. Biological characteristics and/or genetic background can influence the response to treatment. The aim was to assess the value of C-reactive protein and TNF-alpha serum levels before treatment as well as the TNF -308 gene polymorphism in the prediction of response to infliximab treatment in Crohn disease. Methods: Two-hundred-and-twenty-six Crohn disease patients treated in the setting of an expanded access programme to infliximab in Belgium were studied. There were 136 refractory luminal diseases and 90 refractory fistulizing diseases. Luminal diseases were treated with one single infusion; fistulizing diseases with three infusions at weeks 0, 2 and 6. A clinical response to treatment was defined as either a Crohn disease activity index <150 (complete) or a drop of 70 points (partial) at week 4, for luminal disease, and as either complete fistula healing (complete) or a decrease of at least 50% of the number of draining fistulas on two consecutive visits between weeks 0 and 18, for fistulizing disease. CRP and serum TNF-α levels were measured at week 0 before treatment and were compared between responders and non- responders. Patients were genotyped for the -308 TNF gene polymorphism, and allelic as well as genotype frequencies were compared between responders and non- responders. Results: There were 73.2% responders (46.4% complete and 26.8% partial) and 26.8% non- responders. Response rates were similar in luminal and fistulizing diseases. CRP level before treatment was significantly higher in responders than in non-responders (16.8 mg/l (5-160) versus 9.6 mg/l (5-143); P = 0.02). Furthermore, response rate was significantly higher in patients with elevated CRP (> 5 mg/l) than in patients with a normal CRP value (< 5 mg/l) before treatment (76% versus 46%; P = 0.004; OR: 0.26 (0.11-0.63)). Allelic and genotype frequencies for -308 TNF gene polymorphis m were not significantly different between responders and non- responders - with the exception of a slightly higher TNF2 frequency in nonresponders in luminal disease (22.1% versus 11.6%; P = 0.04). However, this was not associated with a significant difference in genotype frequencies. Conclusion: A positive clinical response to infliximab was associated with a higher CRP level before treatment in our population of Crohn disease patients, but there was no relevant association with -308 TNF gene polymorphism. We therefore suggest that CRP level may help to identify better candidates for infliximab treatment. [less ▲]

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See detailApoptosis of HL-60 leukemia cells induced by the bisindole alkaloids sungucine and isosungucine from Strychnos icaja
Lansiaux, A.; Bailly, Christian; Houssier, Claude ULg et al

in Planta Medica (2002), 68(7), 591-595

Sungucine and isosungucine are two bisindole alkaloids isolated from the roots of the African plant Strychnos icaja Baillon. They both exhibit antiplasmodial activities but also show cytotoxic effects ... [more ▼]

Sungucine and isosungucine are two bisindole alkaloids isolated from the roots of the African plant Strychnos icaja Baillon. They both exhibit antiplasmodial activities but also show cytotoxic effects against human cancer cell lines. In order to elucidate their mechanism of action, we have investigated the interaction of the alkaloids with DNA and their capacity to inhibit nucleic acids and protein synthesis in the human HL-60 promyelocytic leukemia cell line. Cell treatment with both sungucine and isosungucine leads to the appearance of a hypo-diploid DNA content peak. Western blotting analysis reveals that the two alkaloids induce cleavage of the poly(ADP-ribose) polymerase (PARP) and promote the cleavage of a caspase-3 DEVD peptide substrate. The activation of the caspase cascade is accompanied with a fragmentation of DNA in cells, as revealed by the TUNEL assay. Altogether, the results shed light on the mechanism of action of these two plant alkaloids and identify signaling factors involved in (iso)sungucine-induced apoptosis in HL-60 cells. [less ▲]

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See detailColloque "Ecrire Ferney"
Tilkin, Françoise ULg

in Bulletin de la Société Voltaire (2002), 3

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See detailMultiyear infrared solar spectroscopic measurements of HCN, CO, C2H6,and C2H2 tropospheric columns above Lauder, New Zealand (45 degrees S latitude)
Rinsland, Curtis P.; Jones, Nicholas B.; Connor, Brian J. et al

in Journal of Geophysical Research. Atmospheres (2002), 107(D14),

[1] Near-simultaneous, 0.0035 or 0.007 cm(-1) resolution infrared solar absorption spectra of tropospheric HCN, C2H2, CO, and C2H6 have been recorded from the Network for the Detection of Stratospheric ... [more ▼]

[1] Near-simultaneous, 0.0035 or 0.007 cm(-1) resolution infrared solar absorption spectra of tropospheric HCN, C2H2, CO, and C2H6 have been recorded from the Network for the Detection of Stratospheric Change station in Lauder, New Zealand (45.04degreesS, 169.68degreesE, 0.37 km altitude). All four molecules were measured on over 350 days with HCN and C2H2 reported for the first time based on a new analysis procedure that significantly increases the effective signal-to-noise of weak tropospheric absorption features in the measured spectra. The CO measurements extend by 2.5 years a database of measurements begun in January 1994 for CO with improved sensitivity in the lower and middle troposphere. The C2H6 measurements lengthen a time series begun in July 1993 with peak sensitivity in the upper troposphere. Retrievals of all four molecules were obtained with an algorithm based on the semiempirical application of the Rodgers optimal estimation technique. Columns are reported for the 0.37- to 12-km-altitude region, approximately the troposphere above the station. The seasonal cycles of all four molecules are asymmetric, with minima in March-June and sharp peaks and increased variability during August-November, which corresponds to the period of maximum biomass burning near the end of the Southern Hemisphere tropical dry season. Except for a possible HCN column decrease, no evidence was found for a statistically significant long-term trend. [less ▲]

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See detailL'architecture Art nouveau à Liège
Charlier, Sébastien ULg

in Nouvelles du Patrimoine (Les) (2002), 97

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See detailAnionic polymerisation of methyl methacrylate with complex initiator system
Nugay, Turgut; Nugay, Nihan; Jérôme, Robert ULg

in Polymer Bulletin (2002), 48(6), 457-462

Polymerisation of methyl methacrylate was conducted by using alkyl lithium/dimethylsulfoxide (DMSO) system as initiator in toluene. A special attention was focused on using some lithium polyetheralkoxides ... [more ▼]

Polymerisation of methyl methacrylate was conducted by using alkyl lithium/dimethylsulfoxide (DMSO) system as initiator in toluene. A special attention was focused on using some lithium polyetheralkoxides as polymerisation promoters at ambient temperatures. Poly(methyl methacrylate) samples were characterized with Gel Permeation Chromatography (GPC), Nuclear Magnetic Resonance Spectroscopy (H-1 NMR) and Differential Scanning Calorimetry (DSC). The positive effect of the mu/sigma type ligands such as lithium 2-(2-methoxyethoxy)ethoxide (LiOEEM), 2-(methoxy)ethoxide (LiOEM) on controlling the living character, molecular weight, stereo regularity and the yield of the produced polymers was demonstrated. It has been found that this approach provided high polymerisation yields and low polydispersity but low initiator efficiency. [less ▲]

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See detailVers une agrégation en sciences : images d'une collaboration
Hindryckx, Marie-Noëlle ULg; Collignon, Viviane ULg; Cornélis, André ULg

in Puzzle (2002), 12

Bilan d'une collaboration entre les didacticiens des sciences physiques, biologiques et chimiques dans le cadre de la réforme de l'agrégation de l'enseignement secondaire supérieur. Deux expériences de ... [more ▼]

Bilan d'une collaboration entre les didacticiens des sciences physiques, biologiques et chimiques dans le cadre de la réforme de l'agrégation de l'enseignement secondaire supérieur. Deux expériences de formation sont racontées et analysées : représentations et démarche expérimentale sur les fruits et légumes en biologie et sur le fonctionnement d'une pile en chimie [less ▲]

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See detailLayered silicate/polyester nanohybrids by controlled ring-opening polymerization
Lepoittevin, Bénédicte; Pantoustier, Nadège; Alexandre, Michaël ULg et al

in Macromolecular Symposia (2002), 183

In this study, layered silicate/aliphatic polyester nanohybrids were synthesized by ring-opening polymerization of c-caprolactone as promoted by the so-called coordination-insertion mechanism. These ... [more ▼]

In this study, layered silicate/aliphatic polyester nanohybrids were synthesized by ring-opening polymerization of c-caprolactone as promoted by the so-called coordination-insertion mechanism. These nanocomposites were formed in presence of montmorillortite surface-modified by ammonium cations bearing hydroxyl group(s), such as bis(2-hydroxyethyl)methyl (hydrogenated tallow alkyl) ammonium. The lactone polymerization could in initiated by all the hydroxyl functions available at the clay surface, after activation into either tin(II) or AI(III) alkoxide active species. Hybrid nanocomposites were accordingly generated through the covalent grafting of every polyester chain onto the filler surface. Surface-grafted polycaprolactone (PCL) chains were untied and isolated by ionic exchange reaction with LiCl in THF solution and molar masses were measured by size exclusion chromatography. The PCL molar masses could be controlled and readily tuned by the content of hydroxyl groups available at the clay surface. Interestingly, initiation reaction by aluminum trialkoxide active species yielded grafted PCL chains characterized by very narrow molecular weight distribution (M-w/M(n)similar to1.2). These polyester-grafted layered silicate nanohybrids displayed complete exfoliation of silicate sheets as shown by X-ray diffraction (XRD) and transmission electron microscopy (TEM). [less ▲]

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See detailComparison of sampling procedures for isolating pulmonary mycoplasmas in cattle
Thomas, Anne; Dizier, Isabelle ULg; Trolin, A. et al

in Veterinary Research Communications (2002), 26(5), 333-339

Three sampling procedures were compared to determine the optimal technique for isolating mycoplasmas in cattle with respiratory diseases. The prevalence of mycoplasmas isolated from these animals is also ... [more ▼]

Three sampling procedures were compared to determine the optimal technique for isolating mycoplasmas in cattle with respiratory diseases. The prevalence of mycoplasmas isolated from these animals is also reported. In the first group, bronchoalveolar lavage (BAL) and nasal swab cultures were compared with the corresponding lung cultures from cattle necropsied for fatal respiratory diseases (n = 20). In a second group, nasal swabs were compared with corresponding BAL cultures in living animals with recurrent respiratory pathologies (n = 49). There was complete agreement between the paired BAL and lung cultures. In contrast, nasal cultures were not representative of the mycoplasmas present in the lower respiratory airways. The relative sensitivity and specificity of the nasal swab technique compared to BAL in living animals confirmed that the nasal swab cultures were not predictive of lower respiratory airway pathogens, such as Mycoplasma bovis. BAL is considered to be the best method for isolating M. bovis in cattle with respiratory diseases as it combines reliability and feasibility under field sampling conditions. In the present study, Mycoplasma dispar (43%) and M. bovis (29%) were mainly isolated in mixed infections. This confirms the need to search for mycoplasmas in routine examinations and to take them into account in therapeutic strategies for respiratory diseases in cattle. [less ▲]

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See detailThe anti-epileptic drug levetiracetam reverses the inhibition by negative allosteric modulators of neuronal GABA- and glycine-gated currents
Rigo, Jean-Michel; Hans, Grégory ULg; Nguyen, Laurent ULg et al

in British Journal of Pharmacology (2002), 136(5), 659-672

1 In this study in vitro and in vivo approaches were combined in order to investigate if the anti-epileptic mechanism(s) of action of levetiracetam (LEV; Keppra(R)) may involve modulation of inhibitory ... [more ▼]

1 In this study in vitro and in vivo approaches were combined in order to investigate if the anti-epileptic mechanism(s) of action of levetiracetam (LEV; Keppra(R)) may involve modulation of inhibitory neurotransmission. 2 GABA- and glycine-gated currents were studied in vitro using whole-cell patch-clamp techniques applied on cultured cerebellar granule, hippocampal and spinal neurons. Protection against clonic convulsions was assessed in vivo in sound-susceptible mice. The effect of LEV was compared with reference anti-epileptic drugs (AEDs): carbamazepine, phenytoin, valproate, clonazepam, phenobarbital and ethosuximide. 3 LEV contrasted the reference AEDs by an absence of any direct effect on glycine-gated currents. At high concentrations, beyond therapeutic relevance, it induced a small reduction in the peak amplitude and a prolongation of the decay phase of GABA-gated currents. A similar action on GABA-elicited currents was observed with the reference AEDs, except ethosuximide. 4 These minor direct effects contrasted with a potent ability of LEV (EC50 = 1-10 muM) to reverse the inhibitory effects of the negative allosteric modulators zinc and beta-carbolines on both GABA(A) and glycine receptor-mediated responses. 5 Clonazepam, phenobarbital and valproate showed a similar ability to reverse the inhibition of beta-carbolines on GABA-gated currents. Blockade of zinc inhibition of GABA responses was observed with clonazepam and ethosuximide. Phenytoin was the only AED together with LEV that inhibited the antagonism of zinc on glycine-gated currents and only clonazepam and phenobarbital inhibited the action of DMCM. 6 LEV (17 mg kg(-1)) produced a potent suppression of sound-induced clonic convulsions in mice. This protective effect was significantly abolished by co-administration of the beta-carboline FG 7142, from a dose of 5 mg kg(-1). In contrast, the benzodiazepine receptor antagonist flumazenil (up to 10 mg kg(-1)) was without any effect on the protection afforded by LEV. 7 The results of the present study suggest that a novel ability to oppose the action of negative modulators on the two main inhibitory ionotropic receptors may be of relevance for the anti-epileptic mechanism(s) of action of LEV. [less ▲]

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See detailRemplacement valvulaire mitral par homogreffe
RADERMECKER, Marc ULg; Canivet, J. L.; Tambwe, W. et al

in Revue Médicale de Liège (2002), 57(7), 459-62

The total homograft replacement of the left AV valve and subvalvular apparatus constitutes a delicate operation, which may prove beneficial in young patients with extensive bacterial endocarditis. The ... [more ▼]

The total homograft replacement of the left AV valve and subvalvular apparatus constitutes a delicate operation, which may prove beneficial in young patients with extensive bacterial endocarditis. The case of a staphylococcal endocarditis in a young drug addicted patient, operated three years previously of mitral valve repair for the same pathology, is presented. In addition to the complete excision of infected tissues and valvular substitution with biological material, this technique has the advantage of avoiding long term anticoagulation. The history, technical key points, and current indications of mitral homograft in the surgery of the left atrio-ventricular valves are reviewed. [less ▲]

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See detailCentral cord syndrome - Response
Martin, Didier ULg

in Journal of Neurosurgery (2002), 97(1, Suppl. S), 159-159

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See detailComment je traite.... Le cancer avance du pancreas par une approche innovante dirigee contre les nouvelles cibles
Polus, Marc ULg; Bours, Vincent ULg; Jerusalem, Guy ULg et al

in Revue Médicale de Liège (2002), 57(7), 428-32

A better knowledge of fundamental mechanisms of carcinogenesis allows the development of novel therapeutic tools specifically targeting the cancer cell. Our understanding of cellular and molecular ... [more ▼]

A better knowledge of fundamental mechanisms of carcinogenesis allows the development of novel therapeutic tools specifically targeting the cancer cell. Our understanding of cellular and molecular mechanisms controlling cellular cycle and cell survival is an important step for new anti-cancer treatments. This review will focus on new therapeutic's strategies in advanced pancreatic cancer. [less ▲]

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See detailRevascularisation arterielle et transfert de lambeau libre pour le sauvetage des membres ischemiques avec perte de tissus mous: une alternative a l'amputation
Heymans, O.; LEMAIRE, Vincent ULg; Nelissen, Xavier ULg et al

in Revue Médicale de Liège (2002), 57(7), 453-4455-8

Severe limb ischemia is a common problem encountered in medical practice. Aggressive attempts at revascularization have extended the limits of limb salvage. However, in certain cases, extended tissue loss ... [more ▼]

Severe limb ischemia is a common problem encountered in medical practice. Aggressive attempts at revascularization have extended the limits of limb salvage. However, in certain cases, extended tissue loss compromises the healing process. It often results in amputation despite bypass graft patency. Microvascular free tissue transfer combined with arterial revascularization allows healing of these wounds and limb preservation. This combined approach is the ultimate alternative to amputation. [less ▲]

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See detailExperimental and theoretical studies of DyIII: radiative lifetimes and oscillator strengths of astrophysical interest
Zhang, Z. G.; Svanberg, S.; Palmeri, P. et al

in Monthly Notices of the Royal Astronomical Society (2002), 334(1), 1-10

The lifetimes of three short-lived levels belonging to the 4f(9) 6p configuration and of two long-lived levels of the 4f(9) 5d configuration of Dy iii have been measured for the first time using time ... [more ▼]

The lifetimes of three short-lived levels belonging to the 4f(9) 6p configuration and of two long-lived levels of the 4f(9) 5d configuration of Dy iii have been measured for the first time using time-resolved laser-induced fluorescence techniques. They are in good agreement with theoretical values calculated within the framework of a pseudo-relativistic configuration interaction approximation. Using the experimental lifetimes and the theoretical branching fractions, a first set of transition probabilities of astrophysical interest has been obtained for Dy III. [less ▲]

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See detailParticularities of the bucco-pharyngeal apparatus in Zenarchopterus kampeni (Pisces : Hemiramphidae) and their probable significance in feeding
Vandewalle, Pierre ULg; Lambert, Vincianne; Parmentier, Eric ULg

in Belgian Journal of Zoology (2002), 132(2), 125-132

The present study shows several new anatomical particularities of the buccal and pharyngeal parts of the halfbeak Zenarchopterus kampeni. The upper buccal jaw consists of premaxillaries and maxillaries ... [more ▼]

The present study shows several new anatomical particularities of the buccal and pharyngeal parts of the halfbeak Zenarchopterus kampeni. The upper buccal jaw consists of premaxillaries and maxillaries tightly joined by ligaments. A 10degrees lowering of the mandible leads to a 30degrees elevation of the upper jaw. The adductor mandibulae is reduced to bundles A(2) and Aomega. As in the Labridae, the lower pharyngeal jaw articulates with the scapular girdle. The upper pharyngeal jaw consists of distinct second pharyngobranchials followed by the third pharyngobranchials fused into a powerful posterior component. This part fits into and slides along a longitudinal ventral gutter of the neuroranium, thanks not only to the dorsal retractor muscles but also to specific retractors of the second pharyngobranchials. The power and dentition of the pharyngeal parts contrasts with the fragility of the buccal elements. [less ▲]

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See detailUse of municipal solid waste incineration residues in the precasting of concrete paving
Courard, Luc ULg; Degeimbre, Robert ULg; Darimont, Anne ULg et al

in Materials and Structures (2002), 35(250), 365-372

Valorisation of Municipal Solid Waste Incineration Residues - excluding ashes - is a positive advance in sustainable development: saving natural resources, decrease in wastes volume stored, reduction of ... [more ▼]

Valorisation of Municipal Solid Waste Incineration Residues - excluding ashes - is a positive advance in sustainable development: saving natural resources, decrease in wastes volume stored, reduction of energy consumption. If good conditions of incineration can be ensured and post-combustion treatments are realised, solid residues are in the form of granular materials usable in construction and civil engineering. Uses in road structures are classical; application for the precasting of paving is quite new and interesting due to the quantity of recycled materials. Mechanical and physical performances of municipal solid waste incineration residues let us to replace a part of the granular skeleton and to obtain similar behaviour as with reference granular composition: splitting resistance, water absorption and resistance to abrasion are optimised. Leaching behaviour is also verified in order to avoid detrimental effect on the environment; it is shown that post-combustion treatments and compacting energy combined with vibration are essential for a good quality product fabrication. [less ▲]

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See detailBlood flow variation in human muscle during electrically stimulated exercise bouts
Vanderthommen, Marc ULg; Depresseux, J. C.; Dauchat, L. et al

in Archives of Physical Medicine & Rehabilitation (2002), 83(7), 936-941

OBJECTIVES: To evaluate, with a high spatial resolution, the blood flow variations in human skeletal muscle during neuromuscular electric stimulation (NMES) and hence to gain better understanding of the ... [more ▼]

OBJECTIVES: To evaluate, with a high spatial resolution, the blood flow variations in human skeletal muscle during neuromuscular electric stimulation (NMES) and hence to gain better understanding of the mechanisms of muscle spatial recruitment during NMES. DESIGN: One thigh was submitted to 3 stimulation bouts of different durations (S1=4min, S2=8min, S3=12min) with a workload corresponding to 10% of quadriceps maximal isometric voluntary torque. SETTING: A cyclotron research center at a Belgian university. PARTICIPANTS: Ten healthy male volunteers. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants were studied with positron emission tomography and H(2)(15)O. Tissue blood flow was evaluated during the last 4 minutes of each stimulation bout in multiple regions of interest (ROIs) selected in the transverse section of the stimulated thigh. RESULTS: Mean tissue blood flow was significantly lower during S1 (5.9+/-1.3mL. min(-1). 100g(-1)) than during S2 (10.6+/-3.4mL. min(-1). 100g(-1)) and S3 (11.6+/-3.7mL. min(-1). 100g(-1)) (P<.05). For each ROI, an arbitrary tissue blood flow activation level of 5mLmin(-1)100g(-1) was fixed. The mean percentage of activated ROIs reached 42.4%, 62.7%, and 63.6% during S1, S2, and S3, respectively. Between S1 and S3, the newly recruited ROIs were preferentially located far from the electrode. CONCLUSION: During NMES, new muscular regions situated far from the stimulation site are recruited. These recruitment mechanisms are particular and contrast with the recruitment of motor units seen during voluntary contraction. [less ▲]

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See detailLes interférences entre le divorce et les pensions de retraite et de survie: le point de la question
Michiels, Olivier ULg

in Divorce : Actualité Juridique, Sociale et Fiscale (2002), 7

L'article examine les conséquences du divorce sur le droit à la pension de retraite et à la pension de survie.

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See detailVila Maria Formation (Silurian, Parana Basin, Brazil): integrated radiometric and palynological age determinations
Mizusaki, A. M. P.; Melo, J. H. G.; Vignol-Lelarge, M. L. et al

in Geological Magazine (2002), 139(4), 453-463

Fresh shale samples taken from a well-known outcrop section of the Silurian Vila Maria Formation, located on the northeastern margin of the Parana Basin (Tres Barras Farm, Goias State, central-western ... [more ▼]

Fresh shale samples taken from a well-known outcrop section of the Silurian Vila Maria Formation, located on the northeastern margin of the Parana Basin (Tres Barras Farm, Goias State, central-western Brazil), have been analysed for both palynological and radiometric age determinations. The rocks yielded a fairly diverse, age-definitive cryptospore assemblage, and the same samples proved suitable for Rb-Sr analysis, despite Silurian sedimentary rocks being rarely suited to radiometric dating techniques. This study thus introduces an alternative, independent method for estimating the minimum depositional age of the Vila Maria Formation. The Rb-Sr age value has been calculated via an isochron diagram that yields 435.9 +/- 7.8 Ma. Accordingly, the latter value is interpreted as the minimum depositional age of the analysed Vila Maria strata, implying their deposition during Llandovery times. This concurs with the palynological results, which indicate an age no older than Early Silurian and, more particularly, favour an Early to Middle Llandovery (Rhuddanian-Early Aeronian) attribution. [less ▲]

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See detailAnatomically informed basis functions for EEG source localization : Combining functional and anatomical constraints
Phillips, Christophe ULg; Rugg, Michael D; Friston, Karl J

in Neuroimage (2002), 16(3), 678-6951

Distributed linear solutions have frequently been used to solve the source localization problem in EEG. Here we introduce an approach based on the weighted minimum norm (WMN) method that imposes ... [more ▼]

Distributed linear solutions have frequently been used to solve the source localization problem in EEG. Here we introduce an approach based on the weighted minimum norm (WMN) method that imposes constraints using anatomical and physiological information derived from other imaging modalities. The anatomical constraints are used to reduce the solution space a priori by modeling the spatial source distribution with a set of basis functions. These spatial basis functions are chosen in a principled way using information theory. The reduced problem is then solved with a classical WMN method. Further (functional) constraints can be introduced in the weighting of the solution using fMRI brain responses to augment spatial priors. We used simulated data to explore the behavior of the approach over a range of the model's hyperparameters. To assess the construct validity of our method we compared it with two established approaches to the source localization problem, a simple weighted minimum norm and a maximum smoothness (Loreta-like) solution. This involved simulations, using single and multiple sources that were analyzed under different levels of confidence in the priors. (C) 2002 Elsevier Science (USA). [less ▲]

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See detailLevels and congener distributions of PCDDs, PCDFs and non-ortho PCBs in Belgian foodstuffs - Assessment of dietary intake
Focant, Jean-François ULg; Eppe, Gauthier ULg; PIRARD, Catherine ULg et al

in Chemosphere (2002), 48(2), 167-179

Congener-specific analyses of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs) and 4 non-ortho (coplanar) polychlorinated biphenyls (cPCBs) were performed on 197 ... [more ▼]

Congener-specific analyses of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs) and 4 non-ortho (coplanar) polychlorinated biphenyls (cPCBs) were performed on 197 foodstuffs samples of animal origin from Belgium during years 2000 and 2001. All investigated matrices (except horse) present background levels lower than the Belgian non-commercialization value of 5 pg TEQ/g fat. Pork was the meat containing the lowest concentration of both PCDD/Fs and cPCBs. The mean background concentration of 2,3,7,8-TCDD toxicity equivalent in milk was 1.1 pg/g of fat, with a congener distribution typical of non-contaminated milk. The relative contribution of 2,3,7,8-TCDD, 2,3,7,8-TCDF, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF to the PCDD/Fs TEQ was 85 +/- 7.9% for all investigated matrices. The cPCBs contribution to the total TEQ was 47 +/- 19.0% for products of terrestrial species and 69 +/- 20.0% for aquatic species. Once the contribution of cPCBs was added to the TEQ, few foodstuffs such as horse, sheep, beef, eggs and cheese presented levels above the future European guidelines that currently only include PCDD/Fs but will be re-evaluated later in order to include 'dioxin-like' PCBs. Based on levels measured in the samples, the estimation of the dietary intake was 65.3 pg WHO-TEQ/day for PCDD/Fs only (1.00 pg WHO-TEQ/kg bw/day, for a 65 kg person) and 132.9 pg WHO-TEQ/day if cPCBs were included (2.04 pg WHO-TEQ/kg bw/day, for a 65 kg person). Meat (mainly beef), dairy products, and fish each account for roughly one third of the intake. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailHematies Hyperdenses et Sphérocytose
Bricteux, Guy ULg; Panagopoulos, A.; Paulus, Jean-Michel ULg

in Revue Médicale de Liège (2002), 57(7), 443-8

A 12-year old female, suffering from recurring episodes of icterus and abdominal pain, is hospitalized in emergency. She is not anemic but her hemogram reveals a high level of hyperdense red blood cells ... [more ▼]

A 12-year old female, suffering from recurring episodes of icterus and abdominal pain, is hospitalized in emergency. She is not anemic but her hemogram reveals a high level of hyperdense red blood cells (32%; controls 0-2.5%) and an abnormal reticulocyte count (201 x 10(3)/microL; controls 29-84 x 10(3)/microL), indicating a 3.5 fold increase in RBC production. The same abnormalities are found in the patient's mother. The blood smear shows few spherocytes. RBC osmotic fragility is increased only after incubation. Hereditary spherocytosis is diagnosed following electrophoresis of membrane proteins which reveals a deficiency in band 3, a protein which links the lipid bilayer to the cytoskeleton. This case of hemolytic anemia-illustrates the physiopathologic and diagnostic significance of hyperdense RBC, which reflect the cell dehydration associated with the membrane disorder. [less ▲]

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See detailLandgrebe et Fink sur l’universalité de la philosophie phénoménologique
Seron, Denis ULg

in Les Etudes philosophiques (2002)

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See detailComment j'explore.... Une hypertension resistante
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2002), 57(7), 475-478

Hypertension is a cardiovascular risk factor which needs a good evaluation before treatment. When this latter is decided, the target is to normalize high blood pressure. This requires a complete ... [more ▼]

Hypertension is a cardiovascular risk factor which needs a good evaluation before treatment. When this latter is decided, the target is to normalize high blood pressure. This requires a complete information of the patient; the latter will also receive individualized non pharmacological advices and, also, possibly different antihypertensive drugs. When blood pressure does not normalize, one must check the blood pressure measurement technique, the compliance to treatment and potential pharmacologic interferences. Secondary hypertension is only considered if resistance to therapy cannot be found. It should be remembered that obesity and sleep apnea disorders are responsible of many instances of refractory hypertension. [less ▲]

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See detailComparative sequence analysis of the INS-IGF2-H19 gene cluster in pigs
Amarger, V.; Nguyen, Minh Ngoc ULg; Van Laere, Anne-Sophie ULg et al

in Mammalian Genome (2002), 13(7), 388-398

IGF2 is the major candidate gene for a paternally expressed Quantitative Trait Locus (QTL) in the pig primarily affecting muscle development. Here we report two sequence contigs together comprising almost ... [more ▼]

IGF2 is the major candidate gene for a paternally expressed Quantitative Trait Locus (QTL) in the pig primarily affecting muscle development. Here we report two sequence contigs together comprising almost 90 kb containing the INS-IGF2 and H19 genes. A comparative sequence analysis of the pig, human, and mouse genomic sequences was conducted to identify the exon/intros organization, all promoters, and other evolutionarily conserved elements. RT-PCR analysis showed that IGF2 transcripts originated from four different promoters and included various combinations of seven untranslated exons together with three coding exons, in agreement with previous findings in other mammals. The observed sequence similarity in intronic and intragenic regions among the three species is remarkable and is most likely explained by the complicated regulation of imprinting and expression of these genes. The general trend was, as expected, a higher sequence similarity between human and pig than between these species and the mouse, but a few exceptions to this rule were noted. This genomic region exhibits several striking features, including a very high GC content, many CpG islands, and a low amount of interspersed repeats. The high GC and CpG content were more pronounced in the pig than in the two other species. The results will facilitate the further characterization of this important QTL in the pig. [less ▲]

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See detailLocation adjustment for the minimum volume ellipsoid estimator
Croux, C.; Haesbroeck, Gentiane ULg; Rousseeuw, P. J.

in Statistics and Computing (2002), 12(3), 191-200

Estimating multivariate location and scatter with both affine equivariance and positive breakdown has always been difficult. A well-known estimator which satisfies both properties is the Minimum Volume ... [more ▼]

Estimating multivariate location and scatter with both affine equivariance and positive breakdown has always been difficult. A well-known estimator which satisfies both properties is the Minimum Volume Ellipsoid Estimator (MVE). Computing the exact MVE is often not feasible, so one usually resorts to an approximate algorithm. In the regression setup, algorithms for positive-breakdown estimators like Least Median of Squares typically recompute the intercept at each step, to improve the result. This approach is called intercept adjustment. In this paper we show that a similar technique, called location adjustment, can be applied to the MVE. For this purpose we use the Minimum Volume Ball (MVB), in order to lower the MVE objective function. An exact algorithm for calculating the MVB is presented. As an alternative to MVB location adjustment we propose L-1 location adjustment, which does not necessarily lower the MVE objective function but yields more efficient estimates for the location part. Simulations compare the two types of location adjustment. We also obtain the maxbias curves of both L-1 and the MVB in the multivariate setting, revealing the superiority of L-1. [less ▲]

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See detailLevel lifetimes in 3p and 3d configurations of Fe XII
Biémont, Emile ULg; Palmeri, P.; Quinet, Pascal ULg et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2002), 20(1), 37-44

Transitions between the five fine-structure levels in the 3s(2)3p(3) ground configuration of Fe XII (P-like) are of interest in astrophysics and terrestrial plasma diagnostics. The decay rates give rise ... [more ▼]

Transitions between the five fine-structure levels in the 3s(2)3p(3) ground configuration of Fe XII (P-like) are of interest in astrophysics and terrestrial plasma diagnostics. The decay rates give rise to level lifetimes in the millisecond range, which have been measured recently at a heavy-ion storage ring. While most of the 3s(2)3p(2)3d levels are short-lived, two of these levels have no El decay channels and may also have millisecond lifetimes. We present HFR and MCDF calculations of the El, M1, E2 and M2 transition rates between the 3s(2)3p(3), 3s3p(4) and 3s(2)3p(2)3d levels and compare the lifetime results to most recent experimental data as well as to other predictions. [less ▲]

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See detailConcepts in plant stress physiology. Application to plant tissue cultures
Gaspar, Thomas ULg; Franck, Thierry ULg; Bisbis, Badia et al

in Plant Growth Regulation (2002), 37(3), 263-285

Because the term stress is used, most often subjectively, with various meanings, this paper first attempts to clarify the physiological definition, and the appropriate terms as responses in different ... [more ▼]

Because the term stress is used, most often subjectively, with various meanings, this paper first attempts to clarify the physiological definition, and the appropriate terms as responses in different situations. The flexibility of normal metabolism allows the development of responses to environmental changes which fluctuate regularly and predictably over daily and seasonal cycles. Thus every deviation of a factor from its optimum does not necessarily result in stress. Stress begins with a constraint or with highly unpredictable fluctuations imposed on regular metabolic patterns that cause bodily injury, disease, or aberrant physiology. Stress is the altered physiological condition caused by factors that tend to alter an equilibrium. Strain is any physical and/or chemical change produced by a stress, i.e. every established condition, which forces a system away from its thermodynamic optimal state. The paper secondly summarises the Strasser's state-change concept which is precisely that suboptimality is the driving force for acclimation (genotype level) or adaptation (population level) to stress. The paper continues with the actual knowledge on the mechanisms of stress recognition and cell signalling. Briefly: plasma membranes are the sensors of environmental changes; phytohormones and second messengers are the transducers of information from membranes to metabolism; carbon balance is the master integrator of plant response; betwixt and between, some genes are expressed more strongly, whereas others are repressed. Reactive oxygen species play key roles in up- and down-regulation of metabolism and structure. The paper shows finally that the above concepts can be applied to plant tissue cultures where the accumulating physiological and genetical deviations (from a normal plant behaviour) are related to the stressing conditions of the in vitro culture media and of the confined environment. The hyperhydrated state of shoots and the cancerous state of cells, both induced under conditions of stress in in vitro cultures, are identified and detailed, because they perfectly illustrate the stress-induced state-change concept. It is concluded that stress responses include either pathologies or adaptive advantages. Stress may thus contain both destructive and constructive elements: it is a selection factor as well as a driving force for improved resistance and adaptive evolution. [less ▲]

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See detailRisk indices and osteoporosis screening: Scope and limits
Ben Sedrine, Wafa ULg; Reginster, Jean-Yves ULg

in Mayo Clinic Proceedings (2002), 77(7), 622-623

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See detailEDDIE C. CAMPBELL live
Sacré, Robert ULg

in Soul Bag (2002), (167), 47-48

Concert au Sang-A-Klang, Luxembourg, 8 mars 2002: compte rendu + Photo WILLIE BLACK (basse)

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See detailNOD2/CARD15 does not influence response to infliximab in Crohn's disease
Vermeire, S.; Louis, Edouard ULg; Rutgeerts, P. et al

in Gastroenterology (2002), 123(1), 106-111

Background

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See detailMeasurements of the ground-state ionization energy and wavelengths for the 1snp P-1(1)*-1s(2) S-1(0) (n=4-9) lines of Mg XI and FVIII
Pal'chikov, V. G.; Faenov, A. Y.; Skobelev, I. Y. et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2002), 35(12), 2741-2754

The wavelengths of the 1snp P-1(1)0-1s(2) S-1(0) transitions in the He-like Mg XI (n = 4-9) and F VIII (n = 4-8) have been measured in laser-produced plasmas. The accuracy of the present measurements (0.4 ... [more ▼]

The wavelengths of the 1snp P-1(1)0-1s(2) S-1(0) transitions in the He-like Mg XI (n = 4-9) and F VIII (n = 4-8) have been measured in laser-produced plasmas. The accuracy of the present measurements (0.4-1.6 mAngstrom) is a large improvement over previous results. The Rydberg series is used to determine the ground-state ionization energy of F VIII and Mg XI: E-ion (F VIII) = 953.96 +/- 0.11 eV, E-ion (Mg XI) = 1761.88 +/- 0.15 eV. These experimental results are compared with theoretical data calculated by the 1/Z-expansion method and the HFR and MCDF approaches. Fairly good agreement between theory and experiment is observed with a precision up to 5 x 10(-5). Radiative corrections to the 1s(2) S-1(0) state are analysed and compared with experiments. It is found that QED corrections to the ground-state ionization energy are significant at the present level of experimental accuracy. [less ▲]

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See detailFull electrochemical synthesis of conducting polymer films chemically grafted to conducting surfaces
Labaye, David E; Jérôme, Christine ULg; Gueskin, V. M. et al

in Langmuir (2002), 18(13), 5222-5230

This paper reports on the full electrochemical synthesis of electrically conducting polymers chemically grafted to conducting surfaces (e.g., glassy carbon, stainless steel, nickel, gold). It is based on ... [more ▼]

This paper reports on the full electrochemical synthesis of electrically conducting polymers chemically grafted to conducting surfaces (e.g., glassy carbon, stainless steel, nickel, gold). It is based on new functional acrylate monomers, i.e., 3-(2-acryloyloxyethyl)thiophene and N-(2-acryloyloxyethyl)pyrrole, whose the synthesis is reported in this work. The polymerization process consists of two electrochemical steps. The first one is the cathodic electrografting of polyacrylate chains bearing a precursor of the conducting polymer in the ester group, either thiophene or pyrrole. In the second step, this precursor is polymerized under anodic polarization, in the presence or not of additional unsubstituted monomer in the electrochemical bath. Cyclic voltammetry was used to confirm that the two-component film is conducting and electrochemically active (reversible doping and dedoping). The chemical composition and the microscopic morphology of these composites were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. [less ▲]

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