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See detailVesical varices in a patient with portal hypertension.
Gaspar, Yves; Detry, Olivier ULg; de Leval, Jean ULg

in New England Journal of Medicine [=NEJM] (2001), 345(20), 1503-4

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See detailPancreas development in zebrafish: early dispersed appearance of endocrine hormone expressing cells and their convergence to form the definitive islet.
Biemar, F.; Argenton, F.; Schmidtke, R. et al

in Developmental Biology (2001), 230(2), 189-203

To begin to understand pancreas development and the control of endocrine lineage formation in zebrafish, we have examined the expression pattern of several genes shown to act in vertebrate pancreatic ... [more ▼]

To begin to understand pancreas development and the control of endocrine lineage formation in zebrafish, we have examined the expression pattern of several genes shown to act in vertebrate pancreatic development: pdx-1, insulin (W. M. Milewski et al., 1998, Endocrinology 139, 1440-1449), glucagon, somatostatin (F. Argenton et al., 1999, Mech. Dev. 87, 217-221), islet-1 (Korzh et al., 1993, Development 118, 417-425), nkx2.2 (Barth and Wilson, 1995, Development 121, 1755-1768), and pax6.2 (Nornes et al., 1998, Mech. Dev. 77, 185-196). To determine the spatial relationship between the exocrine and the endocrine compartments, we have cloned the zebrafish trypsin gene, a digestive enzyme expressed in differentiated pancreatic exocrine cells. We found expression of all these genes in the developing pancreas throughout organogenesis. Endocrine cells first appear in a scattered fashion in two bilateral rows close to the midline during mid-somitogenesis and converge during late-somitogenesis to form a single islet dorsal to the nascent duodenum. We have examined development of the endocrine lineage in a number of previously described zebrafish mutations. Deletion of chordamesoderm in floating head (Xnot homolog) mutants reduces islet formation to small remnants, but does not delete the pancreas, indicating that notochord is involved in proper pancreas development, but not required for differentiation of pancreatic cell fates. In the absence of knypek gene function, which is involved in convergence movements, the bilateral endocrine primordia do not merge. Presence of trunk paraxial mesoderm also appears to be instrumental for convergence since the bilateral endocrine primordia do not merge in spadetail mutants. We discuss our findings on zebrafish pancreatogenesis in the light of evolution of the pancreas in chordates. [less ▲]

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See detailPDX:PBX complexes are required for normal proliferation of pancreatic cells during development.
Dutta, S.; Gannon, M.; Peers, Bernard ULg et al

in Proceedings of the National Academy of Sciences of the United States of America (2001), 98(3), 1065-70

The homeobox factor PDX-1 is a key regulator of pancreatic morphogenesis and glucose homeostasis; targeted disruption of the PDX-1 gene leads to pancreatic agenesis in pdx-1(-/-) homozygotes. Pdx-1 ... [more ▼]

The homeobox factor PDX-1 is a key regulator of pancreatic morphogenesis and glucose homeostasis; targeted disruption of the PDX-1 gene leads to pancreatic agenesis in pdx-1(-/-) homozygotes. Pdx-1 heterozygotes develop normally, but they display glucose intolerance in adulthood. Like certain other homeobox proteins, PDX-1 contains a consensus FPWMK motif that promotes heterodimer formation with the ubiquitous homeodomain protein PBX. To evaluate the importance of PDX-1:PBX complexes in pancreatic morphogenesis and glucose homeostasis, we expressed either wild-type or PBX interaction defective PDX-1 transgenes under control of the PDX-1 promoter. Both wild-type and mutant PDX-1 transgenes corrected glucose intolerance in pdx-1 heterozygotes. The wild-type PDX-1 transgene rescued the development of all pancreatic lineages in pdx-1(-/-) animals, and these mice survived to adulthood. In contrast, pancreata from pdx-1(-/-) mice expressing the mutant PDX-1 transgene were hypoplastic, and these mice died within 3 weeks of birth from pancreatic insufficiency. All pancreatic cell types were observed in pdx-1(-/-) mice expressing the mutant PDX-1 transgene; but the islets were smaller, and increased numbers of islet hormone-positive cells were noted within the ductal epithelium. These results indicate that PDX-1:PBX complexes are dispensable for glucose homeostasis and for differentiation of stem cells into ductal, endocrine, and acinar lineages; but they are essential for expansion of these populations during development. [less ▲]

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See detailReinforcement learning applied to power system oscillations damping
Ernst, Damien ULg

in Proceedings of the 40th Conference on Decision and Control (CDC 2001) (2001)

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See detailHelioseismic Tests of the New Los Alamos LEDCOP Opacities
Neuforge-Verheecke, C.; Guzik, J. A.; Keady, J. J. et al

in Astrophysical Journal (2001), 561(1), 450-454

We compare the helioseismic properties of two solar models, one calibrated with the OPAL opacities and the other with the recent Los Alamos LEDCOP (Light Element Detailed Configuration Opacity) opacities ... [more ▼]

We compare the helioseismic properties of two solar models, one calibrated with the OPAL opacities and the other with the recent Los Alamos LEDCOP (Light Element Detailed Configuration Opacity) opacities. We show that, in the radiative interior of the Sun, the small differences between the two sets of opacities (up to 6% near the base of the convection zone) lead to noticeable differences in the solar structure (up to 0.3% in sound speed), with the OPAL model being the closest to the helioseismic data. More than half of the difference between the two opacity sets results from the interpolation scheme and from the relatively widely spaced temperature grids used in the tables. The remaining 3% intrinsic difference between the OPAL and the LEDCOP opacities in the radiative interior of the Sun is well within the error bars on the opacity calculations resulting from the uncertainties on the physics. We conclude that both the OPAL and LEDCOP opacities produce solar models in close agreement with helioseismic inferences, but discrepancies still persist at the level of 0.6% between the calculated and inferred sound speed in the radiative interior of the Sun. [less ▲]

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See detailGene structure and promoter function of a teleost ribosomal protein: a tilapia (Oreochromis mossambicus) L18 gene
Molina, Alfredo; Iyengar, Arati; Marins, Luis F. et al

in Biochimica et Biophysica Acta (2001), 1520(3), 195-202

We have cloned and characterized a tilapia (Oreochromis mossambicus) L18 ribosomal protein gene, including the complete transcribed region and 488 bp of upstream regulatory sequences. We have also ... [more ▼]

We have cloned and characterized a tilapia (Oreochromis mossambicus) L18 ribosomal protein gene, including the complete transcribed region and 488 bp of upstream regulatory sequences. We have also isolated two L18 cDNAs from another tilapia (Oreochromis niloticus) with a few conservative nucleotide differences. Our results suggest the presence of two genes in both species. Reporter constructs were tested for transient expression in CV1 cells and in microinjected zebrafish and tilapia embryos. The tilapia L18 promoter was able to drive expression of the reporter gene in all three experiments, with no apparent preference for a particular tissue. The tilapia L18 promoter is therefore likely to be a powerful tool to drive tissue-independent gene expression in fish. [less ▲]

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See detailThe ornithine decarboxylase gene is essential for cell survival during early murine development
Pendeville-Samain, Hélène ULg; Carpino, Nick; Marine, Jean-Christophe et al

in Molecular & Cellular Biology (2001), 21(19), 6549-58

Overexpression and inhibitor studies have suggested that the c-Myc target gene for ornithine decarboxylase (ODC), the enzyme which converts ornithine to putrescine, plays an important role in diverse ... [more ▼]

Overexpression and inhibitor studies have suggested that the c-Myc target gene for ornithine decarboxylase (ODC), the enzyme which converts ornithine to putrescine, plays an important role in diverse biological processes, including cell growth, differentiation, transformation, and apoptosis. To explore the physiological function of ODC in mammalian development, we generated mice harboring a disrupted ODC gene. ODC-heterozygous mice were viable, normal, and fertile. Although zygotic ODC is expressed throughout the embryo prior to implantation, loss of ODC did not block normal development to the blastocyst stage. Embryonic day E3.5 ODC-deficient embryos were capable of uterine implantation and induced maternal decidualization yet failed to develop substantially thereafter. Surprisingly, analysis of ODC-deficient blastocysts suggests that loss of ODC does not affect cell growth per se but rather is required for survival of the pluripotent cells of the inner cell mass. Therefore, ODC plays an essential role in murine development, and proper homeostasis of polyamine pools appears to be required for cell survival prior to gastrulation. [less ▲]

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See detailOn a general decomposition of the error of an approximate stress field in elasticity
Debongnie, Jean-François ULg; Beckers, Pierre ULg

in Computer Assisted Mechanics and Engineering Sciences [=CAMES] (2001), 8

The errors of finite element approximations are analysed in a general frame, which is completely independent from the way through which the approximate solution was obtained. It is found that the error ... [more ▼]

The errors of finite element approximations are analysed in a general frame, which is completely independent from the way through which the approximate solution was obtained. It is found that the error always admits decomposition in two terms, namely the equilibrium error and the compatibility error, which are orthogonal. Each of these admits upper and lower bound that can be computed in a post-processing scheme [less ▲]

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See detailje me sens concerné parce que je t'aime
Battisti, Oreste ULg

Conference (2001)

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See detailAuto/biographie. Le dispositif Mallarmé/Verlaine
Durand, Pascal ULg

in Littératures (2001), 44(printemps), 97-119

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See detailAnalyse de la qualité des mesures de flux de CO2 échangés par les écosystèmes forestiers
Heinesch, Bernard ULg

Master of advanced studies dissertation (2001)

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See detailCrystal Structure of Human Peroxiredoxin 5, a Novel Type of Mammalian Peroxiredoxin at 1.5 Ǻ Resolution
Declercq, Jean-Paul; Evrard, Christine ULg; Clippe, André et al

in Journal of Molecular Biology (2001), 311

The peroxiredoxins define an emerging family of peroxidases able to reduce hydrogen peroxide and alkyl hydroperoxides with the use of reducing equivalents derived from thiol-containing donor molecules ... [more ▼]

The peroxiredoxins define an emerging family of peroxidases able to reduce hydrogen peroxide and alkyl hydroperoxides with the use of reducing equivalents derived from thiol-containing donor molecules such as thioredoxin, glutathione, trypanothione and AhpF. Peroxiredoxins have been identified in prokaryotes as well as in eukaryotes. Peroxiredoxin 5 (PRDX5) is a novel type of mammalian thioredoxin peroxidase widely expressed in tissues and located cellularly to mitochondria, peroxisomes and cytosol. Functionally, PRDX5 has been implicated in antioxidant protective mechanisms as well as in signal transduction in cells. We report here the 1.5 Ǻ resolution crystal structure of human PRDX5 in its reduced form. The crystal structure reveals that PRDX5 presents a thioredoxin-like domain. Interestingly, the crystal structure shows also that PRDX5 does not form a dimer like other mammalian members of the peroxiredoxin family. In the reduced form of PRDX5, Cys47 and Cys151 are distant of 13.8 Ǻ although these two cysteine residues are thought to be involved in peroxide reductase activity by forming an intramolecular disul®de intermediate in the oxidized enzyme. These data suggest that the enzyme would necessitate a conformational change to form a disulfide bond between catalytic Cys47 and Cys151 upon oxidation according to proposed peroxide reduction mechanisms. Moreover, the presence of a benzoate ion, a hydroxyl radical scavenger, was noted close to the active-site pocket. The possible role of benzoate in the antioxidant activity of PRDX5 is discussed. [less ▲]

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See detailHeat shock stimulation of a tilapia heat shock protein 70 promoter is mediated by a distal element
Molina, Alfredo; Di Martino, Emmanuel; Martial, Joseph ULg et al

in Biochemical Journal (2001), 356(Pt 2), 353-9

We reported previously that a tilapia (Oreochromis mossambicus) heat shock protein 70 (HSP70) promoter is able to confer heat shock response on a reporter gene after transient expression both in cell ... [more ▼]

We reported previously that a tilapia (Oreochromis mossambicus) heat shock protein 70 (HSP70) promoter is able to confer heat shock response on a reporter gene after transient expression both in cell culture and in microinjected zebrafish embryos. Here we present the first functional analysis of a fish HSP70 promoter, the tiHSP70 promoter. Using transient expression experiments in carp EPC (epithelioma papulosum cyprini) cells and in microinjected zebrafish embryos, we show that a distal heat shock response element (HSE1) at approx. -800 is predominantly responsible for the heat shock response of the tiHSP70 promoter. This element specifically binds an inducible transcription factor, most probably heat shock factor, and a constitutive factor. The constitutive complex is not observed with the non-functional, proximal HSE3 sequence, suggesting that both factors are required for the heat shock response mediated by HSE1. [less ▲]

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See detailDispositions générales
Boularbah, Hakim ULg

in Les voies des recours (Jurisprudence du Code judiciaire) (2001)

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See detailSpécification formelle des mécanismes de support des qualités de service dans l'Internet
Leduc, Guy ULg; Kuty, Ludovic

in Ingénierie des protocoles et qualité de service (2001)

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See detailExperimental identification of a non-linear beam, proper othogonal decomposition
Lenaerts, Vincent; Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg

in International Conference on Structural Systems Identification, Kassel, 2001 (2001)

The aim of the paper is twofold

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See detailTime-dependent wave-packet treatment of the Si4+ + He collision
Vaeck, Nathalie; Bacchus-Montabonel, Marie-Christine; Baloïtcha, Ezinvy et al

in Physical Review. A (2001), 63

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See detailNumerical modelling of lateral-torsional buckling of steel I-beams under fire conditions - Comparison with Eurocode 3
Vila Real, Paulo M. M.; Franssen, Jean-Marc ULg

in Journal of Fire Protection Engineering (2001), 11(2), 112-128

A geometrically and materially non-linear finite element program, i.e., a general model, has been used to determine the lateral-torsional resistance of steel I-beams under fire conditions, according to ... [more ▼]

A geometrically and materially non-linear finite element program, i.e., a general model, has been used to determine the lateral-torsional resistance of steel I-beams under fire conditions, according to the same material properties of Eurocode 3, Part 1-2. Two yield strengths, one cross section, one type of load and four different time exposures to the ISO 834 standard fire have been considered. The numerical results have been compared to the results of the simple model presented in Eurocode 3, Part 1-2. When compared with the general model, this simple model leads to a safety level that depends on the slenderness of the beam, being unsafe for intermediate non-dimensional slenderness. A new proposal has been made for a simple model that ensures a conservative result when compared to the general model. [less ▲]

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See detailWater management of large dams
Mouzelard, Thibaut; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in International Symposium on Environmental Hydraulics (2001)

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