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Peer Reviewed
See detailA new methodology to analyse monthly somatic cell counts
Detilleux, Johann ULg; Volckaert, D.; Leroy, Pascal ULg

(1998)

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See detailNew Methodology to detect toxin-GPCR binding by MALDI-TOF Mass Spectrometry
Echterbille, Julien ULg; De Pauw, Edwin ULg; Gilles, Nicolas et al

Poster (2011)

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity ... [more ▼]

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity for membrane receptors such as ionic channels or G-protein coupled receptors (GPCRs). GPCRs constitute the larger family of receptors since around 800 different kinds of them are knows. GPCRs are the target of around 30% of the current pharmacopeia drugs. Notable examples include Novartis’s Zelnorm, Eli Lilly’s Zyprexa and Schering-Plough’s Clarinex used to treat constipation, schizophrenia and allergies, respectively. Finding new GPCRs ligands appears of prime interest to design new pharmacological tools and potentially discover the drugs of our future. Interestingly, several toxins from venoms have already been described to bind to this particular family of receptor, opening the way to the discovery of new peptide drugs from animal venoms1-2. This work presents a pioneering MALDI-TOF/TOF based strategy to fish new GPCRs ligands from complex mixtures such as venom fractions. Methods The proof of concept of this methodology was built by studying the binding of [Arg8]-vasopressin (AVP) on type 2-vasopressin receptor (V2). Experimentally, fragments of cellular membranes over-expressing V2 receptors were incubated with cone snail’s venom fraction (~30 peptide toxins) doped by a small amount of AVP. After 2 hours incubation, free and bound fractions were carefully purified with a combination of centrifugation and micro column purifications. Samples were finally analyzed with a Bruker Ultraflex II MALDI-TOF/TOF mass spectrometer and the resulting spectra were interpreted with FlexAnalysis (v3.0), BioTools (v3.2) and SequenceEditor (v3.2) bioinformatics’ softwares from Bruker Daltonics. Preliminary data After the incubation of cellular membranes overexpressing V2 GPCR with a complex mixture of peptides doped by AVP, we clearly detect that the only V2 ligand present in the fraction was the AVP. Our result demonstrates the possibility to identify a ligand of GPCRs from a complex peptide mixture, such as venom fractions. Contrary to radiobinding, this approach allows detecting the direct binding of the toxin and does not imply to know a ligand of the studied GPCR before starting the experiments. This opens the way to the deorphanization of receptors (180 orphans GPCRs over 800). Moreover, since the new ligand is detected by mass spectrometry, it is directly identified from the mixture, without additional purification. Its structural characterization can be directly performed by de novo sequencing experiments. The drawback of our approach is the very long (but crucial!) sample preparation as each sample requires 2 purification steps (for both free and bound fraction). The next step of our work will be the automation of the procedure to allow a high-throughput screening of venom fractions on different GPCRs and the discovery of new ligands. Novel aspect GPCR’s ligands discovery by MALDI-TOF/TOF based techniques: a new pharmacological tool. 1 Quinton, L. et al. Isolation and pharmacological characterization of AdTx1, a natural peptide displaying specific insurmountable antagonism of the a1A-adrenoceptor. British Journal of Pharmacology 159, 316-325 (2010). 2 Rouget, C. et al. Identification of a novel snake peptide toxin displaying high affinity and antagonist behaviour for the α2-adrenoceptors. British Journal of Pharmacology 161, 1361-1374, doi:10.1111/j.1476-5381.2010.00966.x (2010). [less ▲]

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See detailNew Methods For Halogenation of [18F]Fluorinated Benzyl Derivatives.
Kech, C.; Lemaire, Christian ULg; Brichard, L. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2005), 48

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See detailNew methods for handling the range dependence of the clutter spectrum in non-sidelooking monostatic STAP radars
Lapierre, Fabian; Van Droogenbroeck, Marc ULg; Verly, Jacques ULg

in International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2003), Proceedings, Volume 5 (2003, April)

We address the problem of detecting slow-moving targets using a non-sideloking monostatic space-time adaptive processing (STAP) radar. The construction of optimum weights at each range implies the ... [more ▼]

We address the problem of detecting slow-moving targets using a non-sideloking monostatic space-time adaptive processing (STAP) radar. The construction of optimum weights at each range implies the estimation of the clutter covariance matrix. This is typically done by straight averaging of neighboring data snapshots. The range-dependence of these snapshots generally results in poor performance. We present two new methods that handle the rangedependence by exploiting the geometry of the direction-Doppler curves. [less ▲]

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See detailNew methods of prenatal screening for trisomy 21
Capelle, Xavier ULg; Schaaps, Jean-Pierre ULg; Foidart, Jean-Michel ULg

in Revue Médicale de Liège (2008), 63(2), 82-6

Down syndrome is the most commonly recognized genetic cause of mental retardation. The risk of trisomy 21 is directly related to maternal age which can be viewed as the first screening test in the 1970's ... [more ▼]

Down syndrome is the most commonly recognized genetic cause of mental retardation. The risk of trisomy 21 is directly related to maternal age which can be viewed as the first screening test in the 1970's. New strategies for Down syndrom, have emerged with higher sensitivity and lower false-positive rate. These strategies are based on sonographic and maternal serum markers. The most specific but complex strategy is based on the integrated test, i.e., the integration of the quadruple test performed in the second trimester to the first trimester combined screening: for a 85% detection rate, the false positive rate is estimated to 0.9%. This strategy deprives the patient of an early diagnosis. Alternatives strategies do exist which can perform similar detection rate but with increasing false positive rate. To date Down syndrom, screening has not been coordinated by a national body; it would be usefull to ensure the sonographist formation, perform quality audit and decrease variations in practice. [less ▲]

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See detaila new methylxanthine lisofylline increases radiosensitivity in air and hypoxia
Coucke, Philippe ULg; Crompton; Greiner et al

Scientific conference (1998, March 04)

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See detailNew Migration and Intergation in Europe
Martiniello, Marco ULg

Scientific conference (2011, September 29)

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See detailNew Migration and new Migrants in Belgium
Martiniello, Marco ULg

Scientific conference (2009, June 11)

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See detail“New Migrations and New Migrants in Belgium”
Martiniello, Marco ULg

Scientific conference (2008, February 01)

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See detailThe new migratory Europe: towards a proactive immigration policy?
Martiniello, Marco ULg

in Parsons, Craig; Smeeding, Timothy (Eds.) Immigration and the Transformation of Europe (2006)

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 18. New minerals and nomenclature modifications approved in 2013
Williams, P; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2013), 77

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 19. New minerals and nomenclature modifications approved in 2014.
Williams, P; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2014), 78

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 20. New minerals and nomenclature modifications approved in 2014.
Williams, P; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2014), 78

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 21. New minerals and nomenclature modifications approved in 2014.
Williams, P; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2014), 78

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 22. New minerals and nomenclature modifications approved in 2014.
Williams, P; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2014), 78

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 24. New minerals and nomenclature modifications approved in 2015.
Halenius, U; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2015), 79

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 25. New minerals and nomenclature modifications approved in 2015.
Halenius, U; Hatert, Frédéric ULg; Pasero, M et al

in Mineralogical Magazine (2015), 79

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