References of "1999"
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See detailStudi testuali 2
Moreno, Paola ULg

in Moyen Age (Le) (1999), CV

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See detailThe value of pretreatment cell kinetic parameters as predictors for radiotherapy outcome in head and neck cancer : a multicenter analysis.
Begg, A-C; Hart, AAM; Dische, S et al

in Radiotherapy & Oncology (1999), 50

Purpose: The aim of this study was to assess the potential of pre-treatment cell kinetic parameters to predict outcome in head and neck cancer patients treated by conventional radiotherapy. Materials and ... [more ▼]

Purpose: The aim of this study was to assess the potential of pre-treatment cell kinetic parameters to predict outcome in head and neck cancer patients treated by conventional radiotherapy. Materials and methods: Data from 11 different centers were pooled. Inclusion criteria were such that the patients received radiotherapy alone, and that the radiotherapy was given in an overall time of at least 6 weeks with a dose of at least 60 Gy. All patients received a tracer dose of either iododeoxyuridine (IdUrd) or bromodeoxyuridine (BrdUrd) intravenously prior to treatment and a tumor biopsy was taken several hours later. The cell kinetic parameters labeling index (LI), DNA synthesis time (Ts) and potential doubling time (Tpot) were subsequently calculated from flow cytometry data, obtained on the biopsies using antibodies against I/BrdUrd incorporated into DNA. Each center carried out their own flow cytometry analysis. Results: From the 11 centers, a total of 476 patients conforming to the inclusion criteria were analyzed. Median values for overall time and total dose were 49 days and 69 Gy, respectively. Fifty one percent of patients had local recurrences and 53% patients had died, the majority from their disease. Median follow-up was 20 months; being 30 months for surviving patients. Multivariate analysis revealed that T-stage, maximum tumor diameter, differentiation grade, N-stage, tumor localization and overall time correlated with locoregional control, in decreasing order of significance. For the cell kinetic parameters, univariate analysis showed that only LI was significantly associated with local control (P=0.02), with higher values correlating with a worse outcome. Ts showed some evidence that patients with longer values did worse, but this was not significant (P=0.06). Tpot showed no trend (P=0.8). When assessing survival in a univariate analysis, neither LI nor Tpot associated with outcome (P=0.4, 0.4, respectively). Surprisingly, Ts did correlate with survival, with longer values being worse (P=0.02). In the multivariate analysis of local control, LI lost its significance (P=0.16). Conclusions: The only pretreatment kinetic parameter for which some evidence was found for an association with local control (the best end-point for testing the present hypothesis) was LI, not Tpot, and this evidence disappeared in a multivariate analysis. It therefore appears that pretreatment cell kinetic measurements carried out using flow cytometry, only provide a relatively weak predictor of outcome after radiotherapy in head and neck cancer. [less ▲]

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See detailStructure of high-temperature fluid selenium
Raty, Jean-Yves ULg; Saul, A.; Gaspard, Jean-Pierre ULg et al

in Physical Review. B : Condensed Matter (1999), 60(4), 2441-24482448

A semiempirical tight-binding energy model is developed for selenium. It includes s and p electrons as well as an empirical description of the dispersion forces that proves necessary at the liquid ... [more ▼]

A semiempirical tight-binding energy model is developed for selenium. It includes s and p electrons as well as an empirical description of the dispersion forces that proves necessary at the liquid densities under study. The band-structure parameters are obtained by fitting abinitio calculations. The simulated liquid structures are in very good agreement with the most recent X-ray scattering and extended X-ray absorption fine-structure experiments in a broad temperature and density range. The Monte Carlo simulations performed show that the complex liquid structures observed result from the breaking and branching of the selenium chains. The total coordination number is shown to result from the balance between one-, two-, and threefold coordinated atoms. The role of these defects is discussed in relationship with the electrical conductivity of the liquid, i.e., the semiconductor-metal and metal-nonmetal transitions observed at high pressures [less ▲]

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See detailThe ribonucleoside diphosphate reductase inhibitor (E)-2'-Deoxy-(fluoromethylene) cytidine, acts as a cytotoxic radiosensitizer on human cancer cell lines in vitro.
Coucke, Philippe ULg; Decosterd, L-A; Li, Y-X et al

in Cancer Research (1999), 59

ABSTRACT (E)-2*-Deoxy-(fluoromethylene)cytidine (FMdC) is known as an inhibitor of ribonucleoside diphosphate reductase, a key enzyme in the de novo pathway of DNA synthesis. FMdC was tested as a modifier ... [more ▼]

ABSTRACT (E)-2*-Deoxy-(fluoromethylene)cytidine (FMdC) is known as an inhibitor of ribonucleoside diphosphate reductase, a key enzyme in the de novo pathway of DNA synthesis. FMdC was tested as a modifier of radiation response in vitro on a human colon carcinoma cell line (WiDr), and the observed radiosensitization was confirmed on two human cervix cancer cell lines (C33-A and SiHa). Using the clonogenic assay, the effect ratio (ER) at a clinically relevant dose level of 2 Gy was 2.10 (50 nM FMdC), 1.70 (30 nM FMdC), and 1.71 (40 nM FMdC) for the three cell lines WiDr, C33-A, and SiHa, respectively. A more detailed analysis of the importance of timing and concentration of FMdC was done on the WiDr cell line alone, yielding an increased ER(2Gy) with increasing concentration and duration of exposure to the drug, ranging from 1.0 (6 h) to 1.8 (72 h) at 30 nM FMdC and from 1.2 (6 h) to 3.5 (24 h) at 300 nM. We investigated the effect of FMdC on the cellular deoxynucleotide triphosphate pool in WiDr cells and demonstrated a marked depletion of dATP and a significant rise of TTP levels. Cell cycle analysis showed early S-phase accumulation induced by FMdC alone, G2-M block induced by irradiation alone, and an increased accumulation of cells in G2-M if both modalities are used. Our data suggest that FMdC is a radiation response modifier in vitro on different cancer cell lines. The observed radiosensitization may in part be explained by alteration of the deoxynucleotide triphosphate pool, which is consistent with the effect of FMdC on ribonucleoside diphosphate reductase. [less ▲]

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See detailEffects of exercise on concentrations of immunoreactive endothelin in bronchoalveolar lavage fluid of normal horses and horses with chronic obstructive pulmonary disease
Benamou, A. E.; Art, Tatiana ULg; Marlin, David J et al

in Equine Veterinary Journal. Supplement (1999), 30

Chronic obstructive pulmonary disease (COPD) represents a major cause of loss of performance in the horse. The role of endothelin (ET), a potent bronchoconstrictive and vasoactive peptide, is currently ... [more ▼]

Chronic obstructive pulmonary disease (COPD) represents a major cause of loss of performance in the horse. The role of endothelin (ET), a potent bronchoconstrictive and vasoactive peptide, is currently being investigated in asthma and other obstructive respiratory diseases in man. We have previously found elevated systemic and pulmonary endothelin levels in horses during exacerbation of COPD. In the present study, our aim was to examine possible variations in ET concentrations occurring during exercise in COPD horses. We compared the effects of intense treadmill exercise on the recovery of endothelin (ET) in the bronchoalveolar lavage fluid (BALF) as well as in arterial and venous blood, in a group of 5 healthy horses and a group of 5 COPD horses studied alternately in remission and while symptomatic. We also investigated the possible correlations between ET levels and pulmonary function tests during the study. While exercise did not affect the ET levels recovered in BALF among controls, it caused a significant increase (P = 0.02) among symptomatic COPD horses. During remission, wide variations of ET levels among horses, at rest and during exercise, made any significant interpretation difficult. No correlation could be found between exercise-induced changes in ET concentrations and pulmonary function tests or changes in arterial oxygen tension with exercise. We conclude that exercise appears to affect the release of ET by the airways in COPD horses, in contrast to healthy horses. It is still unclear, however, whether these differences relate to adjustments of lung function during exercise. [less ▲]

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See detailExamen minéralogique de phosphates de Benguerir (Maroc)
Bastin, David ULg

Report (1999)

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See detailSimulation de l'impact des mesures de l'Agenda 2000 sur le revenu des exploitations agricoles wallonnes
Burny, Philippe ULg; Poncin, F.

in Association belge d'Economie Rurale (Ed.) Troisième workshop pour économistes agricoles : proceedings, Leuven (Heverlee), KUL, 28 April, 1999 (1999)

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See detailImpaired motor coordination and Purkinje cell excitability in mice lacking calretinin
Schiffmann, Serge N.; Cheron, Guy; Lohoff, Ann et al

in Proceedings of the National Academy of Sciences of the United States of America (1999), 96

n the cerebellum, the parallel fiber-Purkinje cell synapse can undergo long-term synaptic plasticity suggested to underlie motor learning and resulting from variations in intracellular calcium ... [more ▼]

n the cerebellum, the parallel fiber-Purkinje cell synapse can undergo long-term synaptic plasticity suggested to underlie motor learning and resulting from variations in intracellular calcium concentration ([Ca2+]i). Ca2+ binding proteins are enriched in the cerebellum, but their role in information processing is not clear. Here, we show that mice deficient in calretinin (Cr-/-) are impaired in tests of motor coordination. An impairment in Ca2+ homeostasis in Cr-/- Purkinje cells was supported by the high Ca2+-saturation of calbindin-D28k in these cells. The firing behavior of Purkinje cells is severely affected in Cr-/- alert mice, with alterations of simple spike firing rate, complex spike duration, and simple spike pause. In contrast, in slices, transmission at parallel fiber- or climbing fiber-Purkinje cell synapses is unaltered, indicating that marked modifications of the firing behavior in vivo can be undetectable in slice. Thus, these results show that calretinin plays a major role at the network level in cerebellar physiology [less ▲]

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See detailDynamique de l'adaptation au temps et modèle de l'horloge interne
Ferrara, André ULg

Doctoral thesis (1999)

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See detailPlants associated with Tentaculites in a new Early Devonian locality from Morocco.
Gerrienne, Philippe ULg; Fairon-Demaret, Muriel ULg; Galtier, J et al

in Abhandlungen der Geologischen Bundesanstalt (1999), 54

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See detailEffects of Nimesulide and Indometacin on Cox-1 and Cox-2: A Comparative Study
de Leval, X.; Dogné, Jean-Michel ULg; Neven, P. et al

in Journal de Pharmacie de Belgique (1999), 54(3), 89-90

Evidence of the existence of two forms of cyclooxygenases and the clinical relevance of COX-2 inhibition led to the development of COX-2 selective NSAIDs. In order to evaluate this selectivity, we have ... [more ▼]

Evidence of the existence of two forms of cyclooxygenases and the clinical relevance of COX-2 inhibition led to the development of COX-2 selective NSAIDs. In order to evaluate this selectivity, we have developed and validated an enzymatic method. The precision and reproducibility of the assay were determined and COX-2 selectivity examined using nimesulide and indometacin. [less ▲]

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See detailRescue of early heart-shaped embryos and plant regeneration of Phaseolus polyanthus Greenm. and Phaseolus vulgaris L.
Geerts, P.; Mergeai, Guy ULg; Baudoin, Jean-Pierre ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (1999), 3(3), 141-148

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See detailIdentification and characterization of mRNAs differentially expressed in thyroid cells stimulated by a mitogenic treatment
Pirson, I.; Behrens, J.; Savonet, V. et al

in Biochimie (1999), 81

he aim of our work is to identify new genes and proteins involved in the control of the proliferation of thyroid cells as putative protooncogenes and antioncogenes. Several strategies are discussed. A ... [more ▼]

he aim of our work is to identify new genes and proteins involved in the control of the proliferation of thyroid cells as putative protooncogenes and antioncogenes. Several strategies are discussed. A first study has allowed to identify three new genes. Further search will use the differential display and gene arrays methodology. The role of the identified proteins coded by the genes is studied in vitro by the search of partner proteins by the double hybrid method and in vivo by mice gene knockout technology [less ▲]

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See detailLes conceptions de l’au-delà en Mésopotamie
Van der Stede, Véronique ULg

Master's dissertation (1999)

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See detailLes Dioxines
Focant, Jean-François ULg; De Pauw, Edwin ULg

Article for general public (1999)

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See detailLes transferts post-mortem : réinterprétation symbolique du lieu d’enterrement dans un contexte de mobilité des populations
Schmitz, Serge ULg

in Espaces et Sociétés (Paris, France) (1999), 99

This article is the result of the study of 10.000 burial certificates. It analyses the movement of corpses in an urban region which houses 510.000 peoples and tends to explain the motivation of cemetery ... [more ▼]

This article is the result of the study of 10.000 burial certificates. It analyses the movement of corpses in an urban region which houses 510.000 peoples and tends to explain the motivation of cemetery choice. It underlines the connections between post-mortem mobility, the different levels of population mobility and culture. [less ▲]

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