Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailIdentification and Relative-quantification of Glycans by Matrix-assisted Laser Desorption/Ionization In-Source Decay with Hydrogen Abstraction
Akasawa, Daiki; Smargiasso, Nicolas ULg; De Pauw, Edwin ULg

in Analytical Chemistry (2012)

The use of specific matrices allows enhancing the scope of in-source decay (ISD) applications in matrix-assisted laser desorption ionization (MALDI) thanks to the specificity of analyte-matrix chemistry ... [more ▼]

The use of specific matrices allows enhancing the scope of in-source decay (ISD) applications in matrix-assisted laser desorption ionization (MALDI) thanks to the specificity of analyte-matrix chemistry. The use of an oxidizing matrix, 5-nitrosalicylic acid (5-NSA) for MALDI-ISD of glycans is shown to promote fragmentation pathways involving radical precursors. Both glycosidic and cross-ring cleavages are promoted by hydrogen abstraction from hydroxyl group of glycans by 5-NSA molecules. Cross-ring cleavage ions are potentially useful in linkage analysis, one of the most critical steps of glycan characterization. Moreover, we show here that isobaric glycans could be distinguished by structure specific ISD ions, and that the molar ratio of glycan isomers in the mixture can be estimated from their fragment ions abundance. The use of 5-NSA also opens the possibility to perform pseudo-MS3 analysis of glycans. Therefore, MALDI-ISD with 5-NSA is a useful method for identification of glycans and semi-quantitative analysis of mixture of glycan isomers. [less ▲]

Detailed reference viewed: 36 (7 ULg)
Full Text
Peer Reviewed
See detailIdentification and structure elucidation of four cannabimimetic compounds in seized products
Denooz, Raphaël ULg; VAN HEUGEN, Jean-Claude ULg; Frederich, Michel ULg et al

in Journal of Analytical Toxicology (2013), 37(2), 56-63

Since 2008, herbal mixtures with synthetic cannabinoid compounds have been sold as incense throughout the world. Although these new drugs are labeled as not for human consumption, these products are ... [more ▼]

Since 2008, herbal mixtures with synthetic cannabinoid compounds have been sold as incense throughout the world. Although these new drugs are labeled as not for human consumption, these products are smoked for their cannabis-like effects. This study reports the structural and spectral elucidation of four cannabimimetic compounds seized in Belgium: (4-methoxyphenyl)-1-(pentyl-1H-indol-3-yl)methanone (RCS-4), 1-(5-fluoropentyl)-3-(1-naphtoyl)indole (AM-2201), 2-(2-chlorophenyl)-1-(1-pentylindol-3-yl)ethanone (JWH-203) and 4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210). Laboratory investigations were conducted by liquid chromatography (LC)–ultraviolet spectroscopy, high-resolution accurate mass detection and nuclear magnetic resonance (NMR) analysis. This combined analytical approach allowed the detection of illicit compounds for which reference materials were not available. To facilitate identification and to complete existing databases, ultraviolet spectra and NMR data of all seized products are presented. Additionally, LC–quadrupole time-of-flight data were recorded to provide absolute identification. [less ▲]

Detailed reference viewed: 89 (37 ULg)
Full Text
Peer Reviewed
See detailIdentification and subcellular distribution of endogenous Ins(1,4,5)P3 3-kinase B in mouse tissues
Hascakova-Bartova, Romana; Pouillon, Valérie; Dewaste, Valérie et al

in Biochemical and Biophysical Research Communications (2004), 323(3), 920-925

Inositol 1,4,5-trisphosphate 3-kinase (IP3-3K) catalyses the phosphorylation of inositol 1,4,5-trisphosphate to inositol 1,3,4,5-tetrakisphosphate. cDNAs encoding three mammalian isoforms have been ... [more ▼]

Inositol 1,4,5-trisphosphate 3-kinase (IP3-3K) catalyses the phosphorylation of inositol 1,4,5-trisphosphate to inositol 1,3,4,5-tetrakisphosphate. cDNAs encoding three mammalian isoforms have been reported and referred to as IP3-3KA, IP3-3KB, and IP3-3KC. IP3-3KB is particularly sensitive to proteolysis at the N-terminus, a mechanism known to generate active fragments of lower molecular mass. Endogenous IP3-3KB has therefore not been formally identified in tissues. We have probed a series of murine tissues with an antibody directed against the C-terminus of IP3-3KB and used IP3-3KB deficient mouse tissues as negative controls. IP3-3KB was shown to be particularly well expressed in brain, lung, and thymus with molecular masses of 110–120 kDa. The identification of the native IP3-3KB by Western blotting for the first time will facilitate further studies of regulation of its activity by specific proteases and/or phosphorylation [less ▲]

Detailed reference viewed: 31 (9 ULg)
Full Text
Peer Reviewed
See detailIdentification and typing of Salmonella serotypes isolated from guinea fowl (Numida meleagris) farms in Benin during four laying seasons (2007-2010)
Boko, C; Kpodekon, T; Duprez, Jean-Noël ULg et al

in Avian Pathology : Journal of the W.V.P.A (2013), 42

Detailed reference viewed: 32 (5 ULg)
Full Text
Peer Reviewed
See detailIdentification and Validation of the Methylated TWIST1 and NID2 Genes through Real-Time Methylation-Specific Polymerase Chain Reaction Assays for the Noninvasive Detection of Primary Bladder Cancer in Urine Samples.
Renard, Isabelle; Joniau, Steven; van Cleynenbreugel, Ben et al

in European urology (2010)

BACKGROUND: Accumulating evidence suggests that DNA methylation markers could serve as sensitive and specific cancer biomarkers. OBJECTIVE: To determine whether a panel of methylated genes would have the ... [more ▼]

BACKGROUND: Accumulating evidence suggests that DNA methylation markers could serve as sensitive and specific cancer biomarkers. OBJECTIVE: To determine whether a panel of methylated genes would have the potential to identify primary bladder cancer (BCa) in voided urine samples. DESIGN, SETTING, AND PARTICIPANTS: A pharmacologic unmasking reexpression analysis in BCa cell lines was initially undertaken to unveil candidate methylated genes, which were then evaluated in methylation-specific polymerase chain reaction (MSP) assays performed on DNA extracted from noncancerous and cancerous bladder tissues. The most frequently methylated genes in cancerous tissues, with 100% specificity, were retained for subsequent MSP analysis in DNA extracted from urine samples to build and validate a panel of potential methylated gene markers. Urine samples were prospectively collected at three urologic centres from patients with histologically proven BCa and processed for use in real-time MSP and cytologic analysis. Patients with nonmalignant urologic disorders were included as controls. MEASUREMENTS: A urine sample was classified as valid when >/=10 copies of the gene encoding ss-actin were measured in the urine sediment genomic DNA. Sensitivity, specificity, and predictive values of the MSP and cytology tests were assessed and compared. RESULTS AND LIMITATIONS: MSP assays performed on 466 of the 496 (94%) valid urine samples identified two genes, TWIST1 and NID2, that were frequently methylated in urine samples collected from BCa patients, including those with early-stage and low-grade disease. The sensitivity of this two-gene panel (90%) was significantly better than that of cytology (48%), with comparable specificity (93% and 96%, respectively). The positive predictive value and negative predictive value of the two-gene panel was 86% and 95%, respectively. CONCLUSIONS: Detection of the methylated TWIST1 and NID2 genes in urine sediments using MSP provides a highly (>/=90%) sensitive and specific, noninvasive approach for detecting primary BCa. TRIAL REGISTRATION: BlCa-001 study - EudraCt 2006-003303-40. [less ▲]

Detailed reference viewed: 97 (6 ULg)
Full Text
Peer Reviewed
See detailIdentification by two-dimensional electrophoresis of a new adhesin expressed by a low-passaged strain of Mycoplasma bovis
Thomas, Anne; Leprince, Pierre ULg; Dizier, Isabelle ULg et al

in Research in Microbiology (2005), 156(5-6, Jun-Jul), 713-718

A significant decrease in adherence rates of Mycoplasma bovis to bovine bronchial epithelial (BBE) cells has been observed after passage of the organism in artificial medium. Analysis of the proteins ... [more ▼]

A significant decrease in adherence rates of Mycoplasma bovis to bovine bronchial epithelial (BBE) cells has been observed after passage of the organism in artificial medium. Analysis of the proteins expressed by M. bovis isolate 2610 by two-dimensional (2-D) electrophoresis demonstrated differences between the cells harvested after the 7th and 116th passage. Three silver-stained prominent spots observed in 2-D electrophoretic separation of protein extracts of the lower-passaged cells were considerably less strongly expressed in the sample from higher-passaged cells. These spots had a molecular mass of approximately 24 kDa and an isoelectric point of about 5. The mass spectrometry analysis of these trypsin-sensitive proteins led to their identification as a unique new member of the Vsps family of membrane-associated proteins. Serum from a mouse immunized with these proteins significantly reduced adherence of M. bovis to BBE cells. This result underlines the function of this new Vsp in adherence of M. bovis to host cells. (c) 2005 Elsevier SAS. All rights reserved. [less ▲]

Detailed reference viewed: 61 (28 ULg)
Full Text
See detailIdentification d'effecteurs de la signalisation Delta/Notch dans la différenciation des cellules endocrines du système digestif
Flasse, Lydie ULg

Doctoral thesis (2012)

Les cellules endocrines du système digestif incluent les cellules pancréatiques, regroupées en ilots de Langherhans et les cellules entéroendocrines, disséminées tout le long de l’épithélium du tube ... [more ▼]

Les cellules endocrines du système digestif incluent les cellules pancréatiques, regroupées en ilots de Langherhans et les cellules entéroendocrines, disséminées tout le long de l’épithélium du tube digestif. Un disfonctionnement de ces cellules peut être à l’origine de graves maladies, en conséquence les cellules endocrine du tractus digestif font l’objet de nombreuses études. Une connaissance précise du mode de fonctionnement mais aussi du développement et de la différenciation de ces cellules est requise afin de pouvoir élaborer de nouveaux traitements. Bien que ces deux populations de cellules endocrines soient situées dans des organes distincts, elles présentent de nombreuses similarités. Ces similitudes se retrouvent au niveau des hormones produites mais également au niveau des facteurs de transcription et des voies de signalisation impliquées dans le développement de ces cellules. La signalisation Notch joue un rôle primordial dans le contrôle de la différenciation des cellules endocrines pancréatiques et intestinales, chez la souris et le zebrafish. L’objectif de ce travail consiste à mieux comprendre les étapes précoces de la différenciation endocrine en recherchant des effecteurs de type ARP/ASCL de la voie de signalisation Delta/Notch, impliqués dans le développement endocrine du tractus digestif. Dans le pancréas, nous montrons que le facteur ascl1b est le premier marqueur pancréatique endocrine à apparaître. Ce facteur qui appartient à la famille des ASCL, est requis pour initier la différenciation de la lignée endocrine. Le facteur neurod1, appartenant à la famille des ARP, agit plus tardivement dans le développement de cette lignée afin de permettre le maintien du programme de différenciation endocrine. Nous démontrons que ces deux facteurs agissent séquentiellement dans les précurseurs endocrines pour promouvoir leur différenciation. La perte simultanée de ces deux facteurs conduit à l’absence totale de cellules endocrine. Dans le tractus gastro-intestinal, nous montrons que la signalisation Delta/Notch réprime le destin sécréteur en inhibant l’expression du facteur ascl1a. La présence de ce facteur est absolument requise pour la différenciation de l’ensemble des cellules sécrétrice. ascl1a est à la base de la cascade de facteur de transcription contrôlant la différenciation des cellules entéroendocrines. Nous montrons également que, dans cet organe, neurod1 régule la différenciation de certains types de cellules entéroendocrines. Parallèlement à cette étude des facteurs ARP/ASCL, nous avons mis en évidence la fonction d’un nouveau régulateur de la différenciation endocrine pancréatique: rfx6. Ce facteur est exclusivement exprimé dans la lignée endocrine chez le zebrafish. En l’absence de rfx6, les précurseurs endocrine sont bloqués dans leur différenciation et s’accumulent. Ce facteur est donc requis pour la différenciation terminale des précurseurs endocrines. [less ▲]

Detailed reference viewed: 81 (19 ULg)
Peer Reviewed
See detailIdentification d’inhibiteurs sélectifs de la cyclooxygénase-2 (COX-2)
Michaux, C.; Julemont, F.; De Leval, X. et al

Conference (2004, June)

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailIdentification d'un certain nombre de raies observées dans les spectres du disque et des taches du soleil
Swings, Polydore ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1933), 115

Detailed reference viewed: 8 (3 ULg)
Peer Reviewed
See detailIdentification d’un inhibiteur COX-2 sélectif », 18èmes Journées Franco-belges de Pharmacochimie
Michaux, C.; Julemont, F.; De Leval, X. et al

Poster (2004, June)

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailIdentification d'une dermatose provoquée par la lumière
PIERARD-FRANCHIMONT, Claudine ULg; CAUCANAS, Marie ULg; QUATRESOOZ, Pascale ULg et al

in Revue Médicale de Liège (2011), 66

Detailed reference viewed: 21 (0 ULg)
See detailIdentification d'une famille porteuse d'une nouvelle mutation bêta-LH accompagnée d'hypogonadisme
Daly, Adrian ULg; Salvi, R.; Ménagé, J.-J. et al

in 23ème Congrès de la Société Française d'Endocrinologie - Abstract book (2006)

Detailed reference viewed: 6 (0 ULg)