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
Peer Reviewed
See detailMolecular analysis of the interfacial and membrane-interacting properties of D-xylose-based bolaforms
Nasir, Mehmet Nail ULg; Legrand, Vincent; Gatard, Sylvain et al

Poster (2012, October)

Detailed reference viewed: 31 (14 ULg)
See detailMolecular Analysis Of The Ycr-242 Gene Encoding The Putative Mitochondrial Asparaginyl-Transfer-Rna Synthetase From Saccharomyces-Cerevisiae
Landrieu, I.; Vandenbol, Micheline ULg; Portetelle, Daniel ULg et al

in Archives Internationales de Physiologie de Biochimie et de Biophysique (1994), 102(2),

Detailed reference viewed: 16 (1 ULg)
Full Text
See detailMolecular and atomic hydrogen in the environment of hot, massive stars
St-Louis, N.; Gervais, S.; Morel, Thierry ULg et al

in Wolf-Rayet Phenomena in Massive Stars and Starburst Galaxies (1999)

Detailed reference viewed: 8 (2 ULg)
Full Text
Peer Reviewed
See detailMolecular and cellular basis of the altered immune response against arsonate in irradiated A/J mice autologously reconstituted.
Ismaili, Jamila; Razanajaona, Diane; Van Acker, Annette et al

in International Immunology (1999), 11(7), 1157-67

The humoral immune response to arsonate (Ars) in normal A/J mice is dominated in the late primary and particularly in the secondary response by a recurrent and dominant idiotype (CRIA) which is encoded by ... [more ▼]

The humoral immune response to arsonate (Ars) in normal A/J mice is dominated in the late primary and particularly in the secondary response by a recurrent and dominant idiotype (CRIA) which is encoded by a single canonical combination of the variable gene segments: VHidcr11-DFL16.1-JH2 and Vkappa10-Jkappa1. Accumulation of somatic mutations within cells expressing this canonical combination or some less frequent Ig rearrangements results in the generation of high-affinity antibodies. By contrast, in partially shielded and irradiated A/J mice (autologous reconstitution) immunized with Ars-keyhole limpet hemocyanin (KLH), both the dominance of the CRIA idiotype and the affinity maturation are lost, whereas the anti-Ars antibody titer is not affected. To understand these alterations, we have analyzed a collection of 27 different anti-Ars hybridomas from nine partially shielded and irradiated A/J mice that had been immunized twice with Ars-KLH. Sequence analysis of the productively rearranged heavy chain variable region genes from those hybridomas revealed that (i) the canonical V(D)J combination was rare, (ii) the pattern of V(D)J gene usage rather corresponded to a primary repertoire with multiple gene combinations and (iii) the frequency of somatic mutations was low when compared to a normal secondary response to Ars. In addition, immunohistological analysis has shown a delay of 2 weeks in the appearance of full blown splenic germinal centers in autoreconstituting mice, as compared to controls. Such a model could be useful to understand the immunological defects found in patients transplanted with bone marrow. [less ▲]

Detailed reference viewed: 47 (0 ULg)
Full Text
See detailMolecular and cellular insights into IKAP and Elongator functions
Close, Pierre ULg

Doctoral thesis (2006)

As the first step in the complex process of gene expression, the transcription of genes from DNA to RNA by RNA polymerase II is subject to a multiplicity of controls and is thereby the endpoint of ... [more ▼]

As the first step in the complex process of gene expression, the transcription of genes from DNA to RNA by RNA polymerase II is subject to a multiplicity of controls and is thereby the endpoint of multiple cell regulatory pathways. We focused here on the molecular and cellular functions of IKAP and by extension of Elongator complex, initially found associated with the hyperphosphorylated RNA polymerase II during the elongation stage of transcription. IKAP is required for the assembly of Elongator subunits into a functional complex. Elongator has a histone acetyltransferase (HAT) activity associated with one of its subunits, named hELP3. In agreement with a potential role in transcript elongation, Elongator is associated with nascent RNA emanating from the elongating RNA polymerase II along the transcribed region of several yeast genes and chromatin immunoprecipitation experiments have also demonstrated an association of Elongator with genes in human cells. Different mutations in the human IKBKAP gene, encoding IKAP/hELP1, cause familial dysautonomia, a severe neurodevelopmental disease with complex clinical characteristics. Affected individuals are born with the disease and abnormally low numbers of neurons in peripheral nervous ganglions. To gain insight into the role played by IKAP and the Elongator complex in the transcription of genes and concomitantly learn about the molecular defects underlying the FD, an RNA interference approach was used to deplete the IKAP protein in human cells. In yeast, disruption of ELP1 (yeast homolog of human IKAP) is known to destabilize the ELP3 catalytic subunit, which leads to loss of Elongator integrity. Our experiments performed in human cells revealed that the levels of hELP3 protein is also affected by IKAP depletion after RNAi. We took advantage of this cellular loss-of-function model to identify genes whose transcription requires IKAP, by microarray experiments. Among the identified candidates, several were previously described to be involved in cell motility, or actin cytoskeleton remodelling. Because cell motility is of crucial importance for the developing nervous system, and therefore of obvious relevance to FD, the potential role of IKAP in cell motility was characterized at the cellular level. Several cell motility/migration assays demonstrated that the IKAP depletion has functional consequences so that IKAP-depleted cells showed defects in migration. Particularly, the reduced cell motility of neuronal-derived cell lines may be highly relevant to the neurodevelopmental disorder that affects FD patients. Whether or not the defects in cell migration resulted of impaired transcriptional elongation of the IKAP-dependent genes was investigated by chromatin immuno-precipitation technique. These experiments indicated that IKAP depletion leads to a decreased histone H3 acetylation in the transcribed region of its target genes in the context of Elongator complex. These acetylation defects are correlated with a decrease of the RNA polymerase II recruitment through the transcribed region of target genes, whereas the recruitment on the promoter is mostly unaffected. These results indicate that Elongator affects transcript elongation in vivo, but not the recruitment of the RNA polymerase II to the promoter. These very specific effects of IKAP/hELP1 depletion on histone acetylation and RNA polymerase II density across target genes are consistent with a direct effect of Elongator on transcriptional elongation in vivo and point to a function for Elongator in histone acetylation during transcript elongation. [less ▲]

Detailed reference viewed: 16 (3 ULg)
Peer Reviewed
See detailMolecular and Clinicopathological Diagnosis of Non-Wildebeest Associated Malignant Catarrhal Fever in Belgium
Desmecht, Daniel ULg; Cassart, Dominique ULg; Rollin, Frédéric ULg et al

in Veterinary Record : Journal of the British Veterinary Association (1999), 144(14), 388

Detailed reference viewed: 11 (2 ULg)
Full Text
Peer Reviewed
See detailMolecular and Morphological Aspects of Annealing-Induced Stabilization of Starch Crystallites
Gomand, Sara; Lamberts, Lieve; Gommes, Cédric ULg et al

in Biomacromolecules (2012), 13

A unique series of potato (mutant) starches with highly different amylopectin/amylose (AP/AM) ratios was annealed in excess water at stepwise increasing temperatures to increase the starch melting (or ... [more ▼]

A unique series of potato (mutant) starches with highly different amylopectin/amylose (AP/AM) ratios was annealed in excess water at stepwise increasing temperatures to increase the starch melting (or gelatinization) temperatures in aqueous suspensions. Small-angle X-ray scattering (SAXS) experiments revealed that the lamellar starch crystals gain stability upon annealing via thickening for high-AM starch, whereas the crystal surface energy decreases for AM-free starch. In starches with intermediate AP/AM ratio, both mechanisms occur, but the surface energy reduction mechanism prevails. Crystal thickening seems to be associated with the cocrystallization of AM with AP, leading to very disordered nanomorphologies for which a new SAXS data interpretation scheme needed to be developed. Annealing affects neither the crystal internal structure nor the spherulitic morphology on a micrometer length scale. [less ▲]

Detailed reference viewed: 37 (0 ULg)
Full Text
Peer Reviewed
See detailA molecular and morphological recircumscription of Brachytheciastrum (Brachytheciaceae, Bryopsida)
Vanderpoorten, Alain ULg; Ignatov, M. S.; Huttunen, S. et al

in Taxon (2005), 54(2), 369-376

ITS, rps4, and atpB-rbcL sequences were used to test recent taxonomic rearrangements in the moss genus Brachytheciastrum. A starting phylogenetic hypothesis of Brachytheciaceae was used to subsample ... [more ▼]

ITS, rps4, and atpB-rbcL sequences were used to test recent taxonomic rearrangements in the moss genus Brachytheciastrum. A starting phylogenetic hypothesis of Brachytheciaceae was used to subsample representative genera of each subfamily to obtain a robust backbone phylogeny and circumscribe Brachytheciastrum within the family. The strongly supported monophyletic Brachytheciastrum clade includes B. bellicum Vanderpoorten, Ignatov, Huttunen [less ▲]

Detailed reference viewed: 31 (4 ULg)
Full Text
Peer Reviewed
See detailMolecular And Morphological Variation Of Rare Endemic Oncocyclus Irises (Iridaceae) Of Lebanon
Saad, Layla ULg; Mahy, Grégory ULg

in Botanical Journal of the Linnean Society (2009), 159

Detailed reference viewed: 26 (2 ULg)
Full Text
Peer Reviewed
See detailMolecular and pigment studies of the picophytoplankton in a region of the Southern Ocean (42-54 degrees S, 141-144 degrees E) in March 1998
Wilmotte, Annick ULg; Demonceau, Caroline; Goffart, Anne ULg et al

in Deep-Sea Research Part II, Topical Studies in Oceanography (2002), 49(16), 3351-3363

Seven filtered seawater samples (depths between 30 and 55 m) collected during the SAZ project of the Austral summer of 1997-1998 were used for a simultaneous study of the picophytoplankton pigments based ... [more ▼]

Seven filtered seawater samples (depths between 30 and 55 m) collected during the SAZ project of the Austral summer of 1997-1998 were used for a simultaneous study of the picophytoplankton pigments based on high-performance liquid chromatography (HPLC) analyses and flow cytometry, and of the molecular diversity of the picophytoplankton based on their rDNA sequences. The sampling sites could be divided into three temperature zones, distinguished by their proximity to the Sub-Antarctic and Polar Fronts. HPLC analysis of total chlorophylls and carotenoids showed fairly low phytoplankton concentrations (77-262 ng chl al(-1)), with minimal values of the pigments in the two samples of the Polar Front Zone around 54degreesS (water temperature of 4degreesC at time of collection). In this zone, a similar decrease of particles, identified as cyanobacteria on the basis of their fluorescence, was observed by flow cytometry. Sequences very similar to the 16S rDNA sequence of Synechococcus WH8103 were present in all samples. This Synechococcus genotype is thus found in the Southern Ocean in addition to the Atlantic and Pacific locations where it has been previously observed. The yield of PCR products was lower in the two samples taken in the Polar Front Zone, showing a good agreement between molecular and pigment data. 16S rDNA sequences of plastids of eukaryotic algae also were retrieved, mostly related to those of an environmental clone called OM164, which has not been cultivated but has phylogenetic affinities to the Raphidophyceae. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 65 (3 ULg)
Full Text
Peer Reviewed
See detailA molecular approach for the rapid, selective and sensitive detection of Exophiala jeanselmei in environmental samples: development and performance assessment of a real-time PCR assay.
Libert, X.; Chasseur, C.; Packeu, A. et al

in Applied Microbiology and Biotechnology (2016), 100(3), 1377-1392

Exophiala jeanselmei is an opportunistic pathogenic black yeast growing in humid environments such as water reservoirs of air-conditioning systems. Because this fungal contaminant could be vaporized into ... [more ▼]

Exophiala jeanselmei is an opportunistic pathogenic black yeast growing in humid environments such as water reservoirs of air-conditioning systems. Because this fungal contaminant could be vaporized into the air and subsequently cause health problems, its monitoring is recommended. Currently, this monitoring is based on culture and microscopic identification which are complex, sometimes ambiguous and time-demanding, i.e., up to 21 days. Therefore, molecular, culture-independent methods could be more advantageous for the monitoring of E. jeanselmei. In this study, we developed a SYBR(R)green real-time PCR assay based on the internal transcribed spacer 2 from the 18S ribosomal DNA complex for the specific detection of E. jeanselmei. The selectivity (100 %), PCR efficiency (95.5 %), dynamic range and repeatability of this qPCR assay were subsequently evaluated. The limit of detection for this qPCR assay was determined to be 1 copy of genomic DNA of E. jeanselmei. Finally, water samples collected from cooling reservoirs were analyzed using this qPCR assay to deliver a proof of concept for the molecular detection of E. jeanselmei in environmental samples. The results obtained by molecular analysis were compared with those of classical methods (i.e., culture and microscopic identification) used in routine analysis and were 100 % matching. This comparison demonstrated that this SYBR(R)green qPCR assay can be used as a molecular alternative for monitoring and routine investigation of samples contaminated by E. jeanselmei, while eliminating the need for culturing and thereby considerably decreasing the required analysis time to 2 days. [less ▲]

Detailed reference viewed: 13 (2 ULg)
Full Text
Peer Reviewed
See detailMolecular bands in cometary spectra. Identifications
Swings, Polydore ULg

in Reviews of Modern Physics (1942), 14

Detailed reference viewed: 4 (0 ULg)
Peer Reviewed
See detailMolecular bases of the interaction between human prolactin and its membrane receptor: A ten year study
KINET, Sandrina; BERNICHTEIN, Sophie; LLOVERA, Marta et al

in Recent research developments in endocrinology (2001), 2

In this review, we make a chronologically overview of a project aimed at deciphering the molecular bases of the mechanism by which prolactin, a pituitary-secreted polypeptidic hormone, interacts with its ... [more ▼]

In this review, we make a chronologically overview of a project aimed at deciphering the molecular bases of the mechanism by which prolactin, a pituitary-secreted polypeptidic hormone, interacts with its membrane receptor, a member of the cytokine receptor superfamily. This study, based essentially on structural and mutational analysis of human prolactin, has identified two regions interacting with the receptor, named binding sites 1 and 2. We have also provided evidence that prolactin induces dimerization of its receptor through its two binding sites, and based on that mechanism of activation, we have engineered and characterized prolactin antagonists able to block the effect of the hormone by competition for receptor binding. Our study has also highlighted the importance of using well characterized bioassays to monitor such a structure-function study since the properties of a given hormone analog were shown to strongly differ depending on the bioassay used. [less ▲]

Detailed reference viewed: 45 (4 ULg)
Full Text
Peer Reviewed
See detailMolecular basis of cold adaptation
D'Amico, Salvino ULg; Claverie, P.; Collins, T. et al

in Philosophical Transactions of the Royal Society of London Series B-Biological Sciences (2002), 357(1423), 917-924

Cold-adapted, or psychrophilic, organisms are able to thrive at low temperatures in permanently cold environments, which in fact characterize the greatest proportion of our planet. Psychrophiles include ... [more ▼]

Cold-adapted, or psychrophilic, organisms are able to thrive at low temperatures in permanently cold environments, which in fact characterize the greatest proportion of our planet. Psychrophiles include both prokaryotic and eukaryotic organisms and thus represent a significant proportion of the living world. These organisms produce cold-evolved enzymes that are partially able to cope with the reduction in chemical reaction rates induced by low temperatures. As a rule, cold-active enzymes display a high catalytic efficiency, associated however, with a low thermal stability. In most cases, the adaptation to cold is achieved through a reduction in the activation energy that possibly originates from an increased flexibility of either a selected area or of the overall protein structure. This enhanced plasticity seems in turn to be induced by the weak thermal stability of psychrophilic enzymes. The adaptation strategies are beginning to be understood thanks to recent advances in the elucidation of the molecular characteristics of cold-adapted enzymes derived from X-ray crystallography, protein engineering and biophysical methods. Psychrophilic organisms and their enzymes have, in recent years, increasingly attracted the attention of the scientific community due to their peculiar properties that render them particularly useful in investigating the possible relationship existing between stability, flexibility and specific activity and as valuable tools for biotechnological purposes. [less ▲]

Detailed reference viewed: 31 (2 ULg)
Peer Reviewed
See detailMolecular Basis of Neuronal Biorhythms and Paroxysms
Grisar, Thierry ULg; Lakaye, Bernard ULg; Thomas, Elizabeth

in Archives of Physiology & Biochemistry (1996), 104(6), 770-4

The molecular basis of the biorhythms are evoked in relation to cerebral EEG rhythms and paroxysms. Basic oscillatory phenomena have been well shown and modeled in systems such as the glycolytic pathway ... [more ▼]

The molecular basis of the biorhythms are evoked in relation to cerebral EEG rhythms and paroxysms. Basic oscillatory phenomena have been well shown and modeled in systems such as the glycolytic pathway, the oscillations of cAMP in amoebas and rhythms of the intracellular cycline during mitosis. In excitable cells the intracellular calcium and cAMP oscillations exhibit a signalling system with many advantages. Thus the question arises: to what extent can the EEG paroxysms observed in epileptic syndrome be due to disturbances in such basic molecular pathways that underlie intracellular molecular oscillations? The usefulness of the absence-rat-model and the implication the T type Ca(2+)-channel of the thalamic nuclei in the pathophysiology of this epileptic syndrome are discussed. [less ▲]

Detailed reference viewed: 23 (2 ULg)
Full Text
See detailMolecular basis of radioresistance
COUCKE, Philippe ULg

Doctoral thesis (1995)

Detailed reference viewed: 46 (17 ULg)
Full Text
Peer Reviewed
See detailMolecular basis of the amylose-like polymer formation catalyzed by Neisseria polysaccharea amylosucrase
Albenne, C.; Skov, L. K.; Mirza, O. et al

in Journal of Biological Chemistry (2004), 279(1), 726-734

Amylosucrase from Neisseria polysaccharea is a remarkable transglucosidase from family 13 of the glycosidehydrolases that synthesizes an insoluble amylose-like polymer from sucrose in the absence of any ... [more ▼]

Amylosucrase from Neisseria polysaccharea is a remarkable transglucosidase from family 13 of the glycosidehydrolases that synthesizes an insoluble amylose-like polymer from sucrose in the absence of any primer. Amylosucrase shares strong structural similarities with alpha-amylases. Exactly how this enzyme catalyzes the formation of alpha-1,4-glucan and which structural features are involved in this unique functionality existing in family 13 are important questions still not fully answered. Here, we provide evidence that amylosucrase initializes polymer formation by releasing, through sucrose hydrolysis, a glucose molecule that is subsequently used as the first acceptor molecule. Maltooligosaccharides of increasing size were produced and successively elongated at their nonreducing ends until they reached a critical size and concentration, causing precipitation. The ability of amylosucrase to bind and to elongate maltooligosaccharides is notably due to the presence of key residues at the OB1 acceptor binding site that contribute strongly to the guidance ( Arg(415), subsite +4) and the correct positioning (Asp(394) and Arg(446), subsite +1) of acceptor molecules. On the other hand, Arg(226) (subsites +2/+3) limits the binding of maltooligosaccharides, resulting in the accumulation of small products (G to G3) in the medium. A remarkable mutant (R226A), activated by the products it forms, was generated. It yields twice as much insoluble glucan as the wild-type enzyme and leads to the production of lower quantities of by-products. [less ▲]

Detailed reference viewed: 17 (0 ULg)
See detailMolecular basis of the cold adaptation of enzymes
D'Amico, Salvino ULg

Scientific conference (2003)

Detailed reference viewed: 2 (0 ULg)