Publications ORBi OA
Bookmark and Share    
Full Text
See detailMECHANICAL PRETREATMENT EFFECT ON CELLULOSE ENZYMATICAL HYDROLYSIS
Jacquet, Nicolas ULg; Paquot, Michel ULg

Poster (2008)

Lignocellulosic materials are very interesting for the production of bioethanol after chemical or enzymatical hydrolysis of cellulose. To optimise production rate and increase the output of these ... [more ▼]

Lignocellulosic materials are very interesting for the production of bioethanol after chemical or enzymatical hydrolysis of cellulose. To optimise production rate and increase the output of these processes, different kinds of pre-treatments (grinding, steam explosion…) are often needed for opening the fibrous structure of the cellulose and increase the specific surface of the materials. The present study is focused on two models of “pure” cellulose (cellulose C200 microtechnik, cellulose FD100 FMC biopolymer) in order to analyse the effects of mechanical pretreatments on the kinetics and yields of hydrolysis. The cristallinity index differentiates the two celluloses. Hydrolysis is realized by a cellulase mix (cellulase Trichoderma reesei C2730, Novozyme; cellobiase Aspergillus niger C6105). Results present the influence of homogenisation pretreatment and analyse differents parameters of this technology. [less ▲]

Detailed reference viewed: 33 (3 ULg)
Full Text
See detailPouvoir et consentement : quelques réflexions impressionnistes
Jacquemain, Marc ULg

in Vrancken, Didier; Dubois, Christophe; Schoenaers, Frédéric (Eds.) Penser la négociation : mélange en hommage à Olgierd Kuty (2008)

L'article confronte deux classiques, "Power" de Steven Lukes et "L'acteur et le système" de Crozier et Friedberg, aux réflexions d'auteurs contemporains comme Beck et Negri sur la nature du pouvoir et son ... [more ▼]

L'article confronte deux classiques, "Power" de Steven Lukes et "L'acteur et le système" de Crozier et Friedberg, aux réflexions d'auteurs contemporains comme Beck et Negri sur la nature du pouvoir et son caractère "immanent". A partir de là, il présente brièvement six propositions sur la nature du pouvoir dans les sociétés démocratiques et le rôle important qu'y joue le consentement. Il termine sur "l'invisibilisation" du pouvoir dans le capitalisme contemporain. [less ▲]

Detailed reference viewed: 35 (5 ULg)
Full Text
Peer Reviewed
See detailDistantly related lipocalins share two conserved clusters of hydrophobic residues: use in homology modeling.
Adam, Benoit; Charloteaux, Benoît ULg; Beaufays, Jérôme ULg et al

in BMC structural biology (2008), 8(1-2), 1-18

BACKGROUND: Lipocalins are widely distributed in nature and are found in bacteria, plants, arthropoda and vertebra. In hematophagous arthropods, they are implicated in the successful accomplishment of the ... [more ▼]

BACKGROUND: Lipocalins are widely distributed in nature and are found in bacteria, plants, arthropoda and vertebra. In hematophagous arthropods, they are implicated in the successful accomplishment of the blood meal, interfering with platelet aggregation, blood coagulation and inflammation and in the transmission of disease parasites such as Trypanosoma cruzi and Borrelia burgdorferi. The pairwise sequence identity is low among this family, often below 30%, despite a well conserved tertiary structure. Under the 30% identity threshold, alignment methods do not correctly assign and align proteins. The only safe way to assign a sequence to that family is by experimental determination. However, these procedures are long and costly and cannot always be applied. A way to circumvent the experimental approach is sequence and structure analyze. To further help in that task, the residues implicated in the stabilisation of the lipocalin fold were determined. This was done by analyzing the conserved interactions for ten lipocalins having a maximum pairwise identity of 28% and various functions. RESULTS: It was determined that two hydrophobic clusters of residues are conserved by analysing the ten lipocalin structures and sequences. One cluster is internal to the barrel, involving all strands and the 310 helix. The other is external, involving four strands and the helix lying parallel to the barrel surface. These clusters are also present in RaHBP2, a unusual "outlier" lipocalin from tick Rhipicephalus appendiculatus. This information was used to assess assignment of LIR2 a protein from Ixodes ricinus and to build a 3D model that helps to predict function. FTIR data support the lipocalin fold for this protein. CONCLUSION: By sequence and structural analyzes, two conserved clusters of hydrophobic residues in interactions have been identified in lipocalins. Since the residues implicated are not conserved for function, they should provide the minimal subset necessary to confer the lipocalin fold. This information has been used to assign LIR2 to lipocalins and to investigate its structure/function relationship. This study could be applied to other protein families with low pairwise similarity, such as the structurally related fatty acid binding proteins or avidins. [less ▲]

Detailed reference viewed: 29 (6 ULg)
Full Text
Peer Reviewed
See detailInteractions between bacterial surfaces and milk proteins, impact on food emulsions stability
Ly, M. H.; Aguedo, Mario ULg; Goudot, S. et al

in Food Hydrocolloids (2008), 22(5), 742-751

Bacteria possess physicochemical surface properties such as hydrophobicity, Lewis acid/base and charge which are involved in physicochemical interactions between cells and interfaces. Moreover, food ... [more ▼]

Bacteria possess physicochemical surface properties such as hydrophobicity, Lewis acid/base and charge which are involved in physicochemical interactions between cells and interfaces. Moreover, food matrices are complex and heterogeneous media, with a microstructure depending on interactions between the components in media (van der Waals, electrostatic or structural forces, etc.). Despite the presence of bacteria in fermented products, few works have investigated how bacteria interact with other food components. The objective of the present study was to determine the effects of the surface properties of lactic acid bacteria on the stability of model food emulsions. The bacteria were added to oil/water emulsions stabilized by milk proteins (sodium caseinate, whey proteins concentrate or whey proteins isolate) at different pH (from 3 to 7.5). The effect of bacteria on the emulsions stability depended on the surface properties of strains and also on the characteristics of emulsions. Flocculation and aggregation phenomena were observed in emulsion at pHs for which the bacterial surface charge was opposed to the one of the proteins. The effects of bacteria on the stability of emulsion depended also on the concentration of cations present in media such as Ca2+. These results show that the bacteria through their surface properties could interact with other compounds in matrices, consequently affecting the stability of emulsions. The knowledge and choice of bacteria depending on their surface properties could be one of the important factors to control the stability of matrices such as fermentation media or fermented products. © 2007 Elsevier Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 17 (0 ULg)
Full Text
See detailAugustinus (Pseudo-), S., De vita christiana
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 9 (0 ULg)
Full Text
See detailPius II (Aeneas Silvio Piccolomini), De duobus amantibus Euryalo et Lucretia
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 15 (0 ULg)
Full Text
See detailMarco Polo, De consuetudinibus et conditionibus orientalium regionum
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 43 (0 ULg)
Full Text
See detailJuan Luis Vives, Introductio ad Sapientiam. Satellitium sive Symbola. Epistolae duae de ratione studii puerilis
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 35 (0 ULg)
Full Text
See detailReinhard von Solms, Eyn gesprech eynes alten erfarnen kriegssmans und bawmeysters mit eynem jungen hauptamnn
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 9 (0 ULg)
Full Text
See detailJohannes Arnoldus Bergellanus, De chalcographiae inventione poema encomiasticum
Adam, Renaud ULg

in De Schepper, Marcus; Kelders, Ann; Pauwels, Jan (Eds.) In de ban van boeken. Grote verzamelaars uit de negentiende eeuw in de Koninklijke Bibliotheek van België (2008)

Detailed reference viewed: 32 (0 ULg)
Full Text
Peer Reviewed
See detailIL-4/IL-13 independent goblet cell hyperplasia in experimental helminth infections.
Marillier, Reece G; Michels, Chesney; Smith, Elizabeth M et al

in BMC Immunology (2008), 9

BACKGROUND: Intestinal mucus production by hyperplasic goblet cells is a striking pathological feature of many parasitic helminth infections and is related to intestinal protection and worm expulsion ... [more ▼]

BACKGROUND: Intestinal mucus production by hyperplasic goblet cells is a striking pathological feature of many parasitic helminth infections and is related to intestinal protection and worm expulsion. Induction of goblet cell hyperplasia is associated with TH2 immune responses, which in helminth infections are controlled primarily by IL-13, and also IL-4. In the study presented here we examine the goblet cell hyperplasic response to three experimental parasitic helminth infections; namely Nippostrongylus brasiliensis, Syphacia obvelata and Schistosoma mansoni. RESULTS: As expected N. brasiliensis infection induced a strong goblet cell hyperplasia dependent on IL-4/IL-13/IL-4Ralpha expression. In contrast, and despite previously published transiently elevated IL-4/IL-13 levels, S. obvelata infections did not increase goblet cell hyperplasia in the colon. Furthermore, induction of goblet cell hyperplasia in response to S. mansoni eggs traversing the intestine was equivalent between BALB/c, IL-4/IL-13-/- and IL-4Ralpha-/- mice. CONCLUSION: Together these data demonstrate that intestinal goblet cell hyperplasia can be independent of TH2 immune responses associated with parasitic helminth infections. [less ▲]

Detailed reference viewed: 22 (11 ULg)
Full Text
Peer Reviewed
See detailAuthentication in stealth distributed hash tables
MacQuire, A.; Brampton, A.; Rai, I. A. et al

in Journal of Systems Architecture (2008), 54(6), 607--618

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailL'image du mois. Une ingestion indigeste"."
Jobe, Jérôme ULg; Brasseur, Edmond ULg; Ghuysen, Alexandre ULg et al

in Revue Médicale de Liège (2008), 63(2), 57-8

Detailed reference viewed: 157 (8 ULg)
Full Text
See detailCoelogyne pulverula or Coelogyne tomentosa
Delaplace, Pierre ULg

in The Journal of the Orchid Society of Great Britain (2008), 57

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailMethodes de mesure de l'age physiologique des tubercules semences de pomme de terre (Solanum tuberosum L.).
Delaplace, Pierre ULg; Fauconnier, Marie-Laure ULg; Du Jardin, Patrick ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2008), 12(2), 171-184

Detailed reference viewed: 48 (13 ULg)
Full Text
Peer Reviewed
See detailProteomic analysis of telomerase inhibition by telomere specific ligands
Mazzucchelli, Gabriel ULg; Gabelica, Valérie ULg; Smargiasso, Nicolas ULg et al

in Anticancer Research (2008), 28(5c), 3257-3258

Telomeres consist of protein complexes and repeated ‘TTAGGG’ double strand DNA sequences ended by a 3’ single strand DNA of the same sequence. Progressive telomere shortening is observed in vitro upon ... [more ▼]

Telomeres consist of protein complexes and repeated ‘TTAGGG’ double strand DNA sequences ended by a 3’ single strand DNA of the same sequence. Progressive telomere shortening is observed in vitro upon cell divisions and with ageing in vivo. At a critical telomere length, shortened telomeres trigger a permanent growth arrest known as replicative senescence. Telomerase is an RNA-dependent DNA polymerase that extends telomeres by adding ‘TTAGGG’ repeats. It consists of a functional RNA component (hTR) which serves as template and a catalytic protein (hTERT) with reverse transcriptase activity. The expression of hTERT alone is sufficient for the immortalisation of cells. Telomerase is highly expressed in tumor cells but at very low level in most somatic cells. These observations make the telomerase an attractive target for anticancer strategies. One of these strategies relies on the use of drug candidates able to stabilize the particular telomere G-quadruplex DNA structures. The stabilization of these structures makes the telomere inaccessible for telomerase and thus inhibits telomerase activity. The effect of the hTERT transfection was first studied on the proteome of human WI38 fibroblast cells (1). Then, the proteome alteration response of hTERT transfected WI38 cells induced by the treatment of two G-quadruplexes ligands, telomestatin and TMPyP4, was analyzed. Both compounds can inhibit telomerase but have different selectivity for the different G-quadruplexes structures. Proteome analysis of the treated cells reveals that TMPyP4 induces much more protein expression alterations than telomestatin probably due to its poor selectivity. TMPyP4 induces especially a drastic down expression of the hnRNPs, a modulation of the proteasome pathway, an apparent decrease of the translation and an over expression of several molecular chaperones. Telomestatin induces in particular an over expression of the protein BCL2A1 which is involved in drug resistance of cancer cells and a probable increase of the translation. Both treatments have a common effect particularly on the molecular chaperone CCT (down expression), HSP90 alpha (over expression) and hnRNP D (down expression). The protein HSP90 alpha is also over expressed in hTERT transfected cells compared to parental cells. This protein is already a promising anticancer target protein due to its central role in oncogenesis and in telomerase activity regulation. 1 Mazzucchelli et al: Proteome Science 6: 12, 2008. [less ▲]

Detailed reference viewed: 130 (25 ULg)
Full Text
See detailPhotodetachment and photodissociation mass spectrometry of DNA multiply charged ions
Gabelica, Valérie ULg; Rosu, Frédéric ULg; De Pauw, Edwin ULg et al

in Beck, Rainer D.; Drabbels, Marcel; Rizzo, Thomas R. (Eds.) Contributions 16th Symposium on Atomic and Surface Physics and Related Topics (2008)

Detailed reference viewed: 50 (2 ULg)
Full Text
See detailLa critique dans la pratique sociologique : questions introductives
Jacquemain, Marc ULg

in Recherches (2008), 5

Defending a critical position in sociology depends simultaneously on a triple choice by the researcher in the fields of ontology, epistemology and ethics. From an ontological point of view, the social may ... [more ▼]

Defending a critical position in sociology depends simultaneously on a triple choice by the researcher in the fields of ontology, epistemology and ethics. From an ontological point of view, the social may be defined as primarily holistic, atomistic, or as being the result of mutual structuration by the parts and the whole. Espitemologically, the position of the researcher may be more realist (social phenomena do exist independantly from our point of view about them) or more constructivist (social phenomena are essentially what people or researchers think they are). considering ethics, the social researcher may act rather as an expert (leaving to the funder of the research the question of the relevance of the object to be investigated) or rather as an intellectual (that chooses himself what is worth investigating or not). The relation between sociology and critics depends crucially on what position the researcher takes within this tri-dimensional frame. [less ▲]

Detailed reference viewed: 62 (2 ULg)