References of "Libioulle, Cécile"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailGenetics of ulcerative colitis: the come-back of interleukin 10.
Louis, Edouard ULg; Libioulle, Cécile ULg; Reenaers, Catherine ULg et al

in Gut (2009), 58(9), 1173-6

Detailed reference viewed: 51 (8 ULg)
Full Text
Peer Reviewed
See detailGenome-wide association defines more than 30 distinct susceptibility loci for Crohn's disease
Barrett, Jeffrey C.; Hansoul, Sarah ULg; Nicolae, Dan L. et al

in Nature Genetics (2008), 40(8), 955-62

Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total ... [more ▼]

Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total of 3,230 cases and 4,829 controls) and carried out replication in 3,664 independent cases with a mixture of population-based and family-based controls. The results strongly confirm 11 previously reported loci and provide genome-wide significant evidence for 21 additional loci, including the regions containing STAT3, JAK2, ICOSLG, CDKAL1 and ITLN1. The expanded molecular understanding of the basis of this disease offers promise for informed therapeutic development. [less ▲]

Detailed reference viewed: 139 (45 ULg)
Full Text
Peer Reviewed
See detailAn insertion-deletion polymorphism in the Interferon Regulatory Factor 5 (IRF5) gene confers risk of inflammatory bowel diseases
Dideberg, Vinciane ULg; Kristjansdottir, G.; Milani, L. et al

in Human Molecular Genetics (2007), 16(24), 3008-3016

The interferon regulatory factor 5 (IRF5) gene encodes a transcription factor that plays an important role in the innate as well as in the cell-mediated immune responses. The IRF5 gene has been shown to ... [more ▼]

The interferon regulatory factor 5 (IRF5) gene encodes a transcription factor that plays an important role in the innate as well as in the cell-mediated immune responses. The IRF5 gene has been shown to be associated with systemic lupus erythematosus and rheumatoid arthritis. We studied whether the IRF5 gene is also associated with inflammatory bowel diseases (IBD), Crohn disease (CD) and ulcerative colitis (UC). Twelve polymorphisms in the IRF5 gene were genotyped in a cohort of 1007 IBD patients (748 CD and 254 UC) and 241 controls from Wallonia, Belgium. The same polymorphisms were genotyped in a confirmatory cohort of 311 controls and 687 IBD patients (488 CD and 192 UC) from Leuven, Belgium. A strong signal of association [P=1.9x10(-5), odds ratio (OR) 1.81 (1.37-2.39)] with IBD was observed for a 5 bp indel (CGGGG) polymorphism in the promoter region of the IRF5 gene. The association was detectable also in CD patients (P=6.8x10(-4)) and was particularly strong among the UC patients [P=5.3x10(-8), OR=2.42 (1.76-3.34)]. The association of the CGGGG indel was confirmed in the second cohort [P=3.2x10(-5), OR=1.59 (1.28-1.98)]. The insertion of one CGGGG unit is predicted to create an additional binding site for the transcription factor SP1. Using an electrophoretic mobility shift assay, we show allele-specific differences in protein binding to this repetitive DNA-stretch, which suggest a potential function role for the CGGGG indel. [less ▲]

Detailed reference viewed: 46 (0 ULg)
Full Text
Peer Reviewed
See detailThe role of the Toll receptor pathway in susceptibility to inflammatory bowel diseases
De Jager, P. L.; Franchimont, D.; Waliszewska, A. et al

in Genes and Immunity (2007), 8(5), 387-397

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors ... [more ▼]

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors (TLR), are critical to the host/pathogen interaction and have been implicated in IBD pathophysiology. To explore the association of genetic variation in TLR pathways with susceptibility to IBD, we performed a replication study and pooled analyses of the putative IBD risk alleles in NFKB1 and TLR4, and we performed a haplotype-based screen for association to IBD in the TLR genes and a selection of their adaptor and signaling molecules. Our genotyping of 1539 cases of IBD and pooled analysis of 4805 cases of IBD validates the published association of a TLR4 allele with risk of IBD (odds ratio (OR): 1.30, 95% confidence interval (CI): 1.15 - 1.48; P = 0.00017) and Crohn's disease (OR: 1.33, 95% CI: 1.16 - 1.54; P = 0.000035) but not ulcerative colitis. We also describe novel suggestive evidence that TIRAP (OR: 1.16, 95% CI: 1.04 - 1.30; P = 0.007) has a modest effect on risk of IBD. Our analysis, therefore, offers additional evidence that the TLR4 pathway - in this case, TLR4 and its signaling molecule TIRAP - plays a role in susceptibility to IBD. [less ▲]

Detailed reference viewed: 25 (3 ULg)
Full Text
Peer Reviewed
See detailNovel Crohn disease locus identified by genome-wide association maps to a gene desert on 5p13.1 and modulates expression of PTGER4.
Libioulle, Cécile ULg; Louis, Edouard ULg; Hansoul, Sarah ULg et al

in PLoS Genetics (2007), 3(4), 538-543

To identify novel susceptibility loci for Crohn disease (CD), we undertook a genome-wide association study with more than 300,000 SNPs characterized in 547 patients and 928 controls. We found three ... [more ▼]

To identify novel susceptibility loci for Crohn disease (CD), we undertook a genome-wide association study with more than 300,000 SNPs characterized in 547 patients and 928 controls. We found three chromosome regions that provided evidence of disease association with p-values between 10(-6) and 10(-9). Two of these (IL23R on Chromosome 1 and CARD15 on Chromosome 16) correspond to genes previously reported to be associated with CD. In addition, a 250-kb region of Chromosome 5p13.1 was found to contain multiple markers with strongly suggestive evidence of disease association (including four markers with p < 10(-7)). We replicated the results for 5p13.1 by studying 1,266 additional CD patients, 559 additional controls, and 428 trios. Significant evidence of association (p < 4 x 10(-4)) was found in case/control comparisons with the replication data, while associated alleles were over-transmitted to affected offspring (p < 0.05), thus confirming that the 5p13.1 locus contributes to CD susceptibility. The CD-associated 250-kb region was saturated with 111 SNP markers. Haplotype analysis supports a complex locus architecture with multiple variants contributing to disease susceptibility. The novel 5p13.1 CD locus is contained within a 1.25-Mb gene desert. We present evidence that disease-associated alleles correlate with quantitative expression levels of the prostaglandin receptor EP4, PTGER4, the gene that resides closest to the associated region. Our results identify a major new susceptibility locus for CD, and suggest that genetic variants associated with disease risk at this locus could modulate cis-acting regulatory elements of PTGER4. [less ▲]

Detailed reference viewed: 104 (11 ULg)
Peer Reviewed
See detailChanges in major intracellular osmolytes in L-929 cells following rapid and slow application of hyperosmotic media.
Libioulle, Cécile ULg; Corbesier, L.; Gilles, Raymond ULg

in Comparative Biochemistry & Physiology Part A : Molecular & Integrative Physiology (2001), 130(3), 461-70

Cultured L-929 cells respond to media-made hyperosmotic (600 mOsmol/kg H2O) by addition of NaCl, sorbitol or proline by adjusting successively their intracellular level in different osmolytes: Na+, K ... [more ▼]

Cultured L-929 cells respond to media-made hyperosmotic (600 mOsmol/kg H2O) by addition of NaCl, sorbitol or proline by adjusting successively their intracellular level in different osmolytes: Na+, K+, amino acids and sorbitol. In the NaCl medium, Na+ and K+ are first to increase. Their concentration is then down-regulated while they are replaced by less disrupting osmolytes: amino acids and sorbitol. The amino-acid level is also adjusted with respect to the increase in sorbitol which starts only after 24 h, depending on the induction of aldose reductase. A similar evolution in the amount of these osmolytes is observed, with different time scales and amplitudes, depending on whether the osmotic shocks are applied abruptly or slowly, in a more physiological way. The interplay between the osmolytes is also different depending on their availability in the external medium. Such complex evolutions indicate that a cascade of interacting signals must be considered to account for the overall regulation process. It can hardly be fitted into a model implicating a single primary signalling event (early increase in ions or decrease in cell volume) as usually postulated. Also, the volume up-regulation is not significantly different in the different conditions, showing that it is not primarily dependent on the adjustment of the intracellular osmolarity which is reached immediately upon cell shrinkage and is maintained all over, independently of the availability and changes in nature of the osmolytes. [less ▲]

Detailed reference viewed: 15 (2 ULg)
See detailMolecular adaptations of alpha-amylase from psychrophilic bacteria
Feller, Georges ULg; LIBIOULLE, Cécile ULg; Payan, Françoise et al

Poster (1995)

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailEffect of high osmolarity acclimation on tolerance to hyperosmotic shocks in L929 cultured cells.
Gilles, Raymond ULg; Belkhir, M.; Compère, Philippe ULg et al

in Tissue & Cell (1995), 27(6), 679-687

Application of abrupt, large hyperosmotic shocks induces in L929 cultured cells changes similar to those previously described in other cell types, notably a hypercondensation of the nuclear chromatin ... [more ▼]

Application of abrupt, large hyperosmotic shocks induces in L929 cultured cells changes similar to those previously described in other cell types, notably a hypercondensation of the nuclear chromatin. This paper shows that; 1) this phenomenon is concomitant with a complete disappearance of deoxyribonucleic acid, as visualized by immunogold labelling, from the nucleoplasmic spaces; 2) acclimation to high osmolarities (600 mOsm) by addition to the culture medium of NaCl, sorbitol or proline protects the cells from these effects, which appear to be largely attenuated-acclimated cells also survive much better to the osmotic shock than do control cells and; 3) the best protection seems to be provided by sorbitol and NaCl. Proline acclimation is less effective. These effects are discussed in terms of increased tolerance to NaCl load induced at the level of different macromolecules by so-called 'compensatory' organic compounds. [less ▲]

Detailed reference viewed: 46 (3 ULg)
Peer Reviewed
See detailMolecular adaptations of alpha-amylase from psychrophilic bacteria.
Feller, Georges ULg; LIBIOULLE, Cécile ULg; Payan, Françoise et al

Poster (1994)

Detailed reference viewed: 8 (0 ULg)
Peer Reviewed
See detailMolecular adaptations of alpha-amylase from psychrophilic bacteria
Feller, Georges ULg; LIBIOULLE, Cécile ULg; Payan, Françoise et al

Poster (1994)

Detailed reference viewed: 4 (0 ULg)
Peer Reviewed
See detailMolecular adaptations of alpha-amylase from psychrophilic bacteria
Feller, Georges ULg; LIBIOULLE, Cécile ULg; Payan, Françoise et al

Poster (1994)

Detailed reference viewed: 2 (0 ULg)
Full Text
Peer Reviewed
See detailPurification, Characterization, and Nucleotide Sequence of the Thermolabile Alpha-Amylase from the Antarctic Psychrotroph Alteromonas Haloplanctis A23
Feller, Georges ULg; Lonhienne, T.; Deroanne, Christophe ULg et al

in Journal of Biological Chemistry (1992), 267(8), 5217-21

The alpha-amylase excreted by the antarctic bacterium Alteromonas haloplanctis was purified and the corresponding amy gene was cloned and sequenced. N- and C-terminal amino acid sequencing were used to ... [more ▼]

The alpha-amylase excreted by the antarctic bacterium Alteromonas haloplanctis was purified and the corresponding amy gene was cloned and sequenced. N- and C-terminal amino acid sequencing were used to establish the primary structure of the mature A. haloplanctis alpha-amylase which is composed of 453 amino acids with a predicted Mr of 49,340 and a pI of 5.5. Three Ca2+ ions are bound per molecule and its activity is modulated by chloride ions. Within the four consensus sequences, Asp-174, Glu-200, and Asp-264 are the proposed catalytic residues. The psychrotrophic A. haloplanctis alpha-amylase is characterized by a high amylolytic activity at low temperatures, a reduced apparent optimal temperature, and typical thermodynamic activation parameters A. haloplanctis alpha-amylase has also a low thermal stability as demonstrated by the temperature effect on both activity and secondary structure. It is suggested that structure flexibility and lower sensitivity of secondary structure to temperature variations in the low temperature range are the main structural adaptations of the psychrotrophic enzyme. The unusual stacking of small amino acids around the catalytic residues is proposed as a factor inducing active site flexibility and concomitant high activity of the enzyme at low temperatures. [less ▲]

Detailed reference viewed: 19 (4 ULg)