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See detailFusogenic Alzheimer'S Peptide Fragment A Beta (29-42) In Interaction With Lipid Bilayers: Secondary Structure, Dynamics, And Specific Interaction With Phosphatidyl Ethanolamine Polar Heads As Revealed By Solid-State Nmr
Ravault, S.; Soubias, O.; Saurel, O. et al

in Protein Science : A Publication of the Protein Society (2005), 14(5), 1181-9

The interaction of the native Alzheimer's peptide C-terminal fragment Abeta (29-42), and two mutants (G33A and G37A) with neutral lipid bilayers made of POPC and POPE in a 9:1 molar ratio was investigated ... [more ▼]

The interaction of the native Alzheimer's peptide C-terminal fragment Abeta (29-42), and two mutants (G33A and G37A) with neutral lipid bilayers made of POPC and POPE in a 9:1 molar ratio was investigated by solid-state NMR. This fragment and the lipid composition were selected because they represent the minimum requirement for the fusogenic activity of the Alzheimer's peptide. The chemical shifts of alanine methyl isotropic carbon were determined by MAS NMR, and they clearly demonstrated that the major form of the peptide equilibrated in membrane is not in a helical conformation. (2)H NMR, performed with acyl chain deuterated POPC, demonstrated that there is no perturbation of the acyl chain's dynamics and of the lipid phase transition temperature. (2)H NMR, performed with alanine methyl-deuterated peptide demonstrated that the peptide itself has a limited mobility below and above the lipid phase transition temperature (molecular order parameter equal to 0.94). MAS (31)P NMR revealed a specific interaction with POPE polar head as seen by the enhancement of POPE phosphorus nuclei T(2) relaxation. All these results are in favor of a beta-sheet oligomeric association of the peptide at the bilayer interface, preferentially recruiting phosphatidyl ethanolamine polar heads. [less ▲]

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See detailFusogenic Properties Of The C-Terminal Domain Of The Alzheimer Beta-Amyloid Peptide
Pillot, T.; Goethals, M.; Vanloo, B. et al

in Journal of Biological Chemistry (1996), 271(46), 28757-65

A series of natural peptides and mutants, derived from the Alzheimer beta-amyloid peptide, was synthesized, and the potential of these peptides to induce fusion of unilamellar lipid vesicles was ... [more ▼]

A series of natural peptides and mutants, derived from the Alzheimer beta-amyloid peptide, was synthesized, and the potential of these peptides to induce fusion of unilamellar lipid vesicles was investigated. These peptide domains were identified by computer modeling and correspond to respectively the C-terminal (e.g. residues 29-40 and 29-42) and a central domain (13-28) of the beta-amyloid peptide. The C-terminal peptides are predicted to insert in an oblique way into a lipid membrane through their N-terminal end, while the mutants are either parallel or perpendicular to the lipid bilayer. Peptide-induced vesicle fusion was demonstrated by several techniques, including lipid-mixing and core-mixing assays using pyrene-labeled vesicles. The effect of peptide elongation toward the N-terminal end of the entire beta-amyloid peptide was also investigated. Peptides corresponding to residues 22-42 and 12-42 were tested using the same techniques. Both the 29-40 and 29-42 beta-amyloid peptides were able to induce fusion of unilamellar lipid vesicles and calcein leakage, and the amyloid 29-42 peptide was the most potent fusogenic peptide. Neither the two mutants or the 13-28 beta-amyloid peptide had any fusogenic activity. Circular dichroism measurements showed an increase of the alpha-helical content of the two C-terminal peptides at increasing concentrations of trifluoroethanol, which was accompanied by an increase of the fusogenic potential of the peptides. Our data suggest that the alpha-helical content and the angle of insertion of the peptide into a lipid bilayer are critical for the fusogenic activity of the C-terminal domain of the amyloid peptide. The differences observed between the fusogenic capacity of the amyloid 29-40 and 29-42 peptides might result from differences in the degree of penetration of the peptides into the membrane and the resulting membrane destabilization. The longer peptides, residues 22-42 and 12-42, had decreased, but significant, fusogenic properties associated with perturbation of the membrane permeability. These data suggest that the fusogenic properties of the C-terminal domain of the beta-amyloid peptide might contribute to the cytotoxicity of the peptide by destabilizing the cell membrane. [less ▲]

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See detailFusogenic Segments Of Bovine Leukemia-Virus And Simian Immunodeficiency Virus Are Interchangeable And Mediate Fusion By Means Of Oblique Insertion In The Lipid Bilayer Of Their Target-Cells
Voneche, V.; Portetelle, Daniel ULg; Kettmann, Richard ULg et al

in Proceedings of the National Academy of Sciences of the United States of America (1992), 89(9),

Modified bovine leukemia virus (BLV) glycoproteins were expressed by using vaccinia virus recombinants, and their fusogenic capacities were examined by a syncytia-formation assay. This analysis indicates ... [more ▼]

Modified bovine leukemia virus (BLV) glycoproteins were expressed by using vaccinia virus recombinants, and their fusogenic capacities were examined by a syncytia-formation assay. This analysis indicates that (i) both BLV envelope glycoproteins gp51 and gp30 are necessary for cell fusion; (ii) insertion of the N-terminal segment of gp30 (fusion peptide) into the lipid bilayer in an oblique orientation, as predicted by computer conformational analysis, results in fusogenic capacities higher than insertion in a perpendicular or parallel orientation; and (iii) replacement of the BLV fusion peptide with its simian immunodeficiency virus counterpart does not modify the fusogenic capacity of the BLV glycoprotein. [less ▲]

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See detailFusogenic Tilted Peptides Induce Nanoscale Holes In Supported Phosphatidylcholine Bilayers
El Kirat, K.; Lins, Laurence ULg; Brasseur, Robert ULg et al

in Langmuir (2005), 21(7), 3116-21

Tilted peptides are known to insert in lipid bilayers with an oblique orientation, thereby destabilizing membranes and facilitating membrane fusion processes. Here, we report the first direct ... [more ▼]

Tilted peptides are known to insert in lipid bilayers with an oblique orientation, thereby destabilizing membranes and facilitating membrane fusion processes. Here, we report the first direct visualization of the interaction of tilted peptides with lipid membranes using in situ atomic force microscopy (AFM) imaging. Phase-separated supported dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC) bilayers were prepared by fusion of small unilamellar vesicles and imaged in buffer solution, in the absence and in the presence of the simian immunodeficiency virus (SIV) peptide. The SIV peptide was shown to induce the rapid appearance of nanometer scale bilayer holes within the DPPC gel domains, while keeping the domain shape unaltered. We attribute this behavior to a local weakening and destabilization of the DPPC domains due to the oblique insertion of the peptide molecules. These results were directly correlated with the fusogenic activity of the peptide as determined using fluorescently labeled DOPC/DPPC liposomes. By contrast, the nontilted ApoE peptide did not promote liposome fusion and did not induce bilayer holes but caused slight erosion of the DPPC domains. In conclusion, this work provides the first direct evidence for the production of stable, well-defined nanoholes in lipid bilayer domains by the SIV peptide, a behavior that we have shown to be specifically related to the tilted character of the peptide. A molecular mechanism underlying spontaneous insertion of the SIV peptide within lipid bilayers and the subsequent removal of bilayer patches is proposed, and its relevance to membrane fusion processes is discussed. [less ▲]

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See detailFutur Antérieur ? L'«Auffang-Lager» de Breendonk et l'univers concentrationnaire nazi (1933-1945)
Jadoulle, Jean-Louis ULg

Book published by Institut Sainte-Marie (1993)

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See detailLe futur centre intégré d'oncologie de Liège (CIO) : analyse des besoins de l'équipe de radiothérapie-oncologie. L'application des principes de 'healing environment'
JANSEN, Nicolas ULg

Conference given outside the academic context (2012)

Dans le cadre des projets futurs du CHU de Liege de construire un 'Centre Intégré d'Oncologie', les besoins du service de radiothérapie ont été analysés et documentés. Les points importants ont été ... [more ▼]

Dans le cadre des projets futurs du CHU de Liege de construire un 'Centre Intégré d'Oncologie', les besoins du service de radiothérapie ont été analysés et documentés. Les points importants ont été soulignés, comme entre autres la surface nécessaire, l'évolution rapide de la radiothérapie, le concept de 'healing environment', le cout potentiel, l'importance de la circulation, la communication avec le monde externe, ... [less ▲]

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See detailLe futur de la recherche en droit successoral
Moreau, Pierre ULg

in L'avenir de la recherche, réflexions à l'occasion des Leçons inaugurales 2010 (2010)

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See detailLe futur des télécommunications
Van Droogenbroeck, Marc ULg

Conference given outside the academic context (2001)

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See detailFutur et modalité : le paradigme du Futur III en néo-égyptien
Polis, Stéphane ULg

Conference (2005, October 09)

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See detailFuture anthropogenic emissions and climate change impact on the carbon cycle; a study with the LOVECLIM model
Mouchet, Anne ULg; Driesschaert, E.; Fichefet, T. et al

Conference (2005, May)

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See detailFuture CCD and CSH variations: Deep-sea impact of ocean acidification
Munhoven, Guy ULg

Poster (2009, June)

The evolutions of atmospheric CO2 partial pressure (pCO2) and of the carbonate compensation depth and the calcite and aragonite saturation horizons (CSH and ASH, respectively) have been studied with the ... [more ▼]

The evolutions of atmospheric CO2 partial pressure (pCO2) and of the carbonate compensation depth and the calcite and aragonite saturation horizons (CSH and ASH, respectively) have been studied with the coupled oceansediment model MBM-MEDUSA [1], over the next 50,000 years. MBM-MEDUSA includes a full description of sedimentary exchange processes, taking into account chemical carbonate erosion in a consistent way. The adopted emission scenarios were based upon logistic functions [2], considering total emissions of 500, 1000, 2000 and 4240 GtC); the adopted stabilisation scenarios were the S350, S450, S550, S650 and S750 from the IPCC [3]. While the evolutions of atmospheric pCO2 and pH have got a great deal of attention so far (e.g., [4, 5]), only a few studies have considered the saturation horizons [5, 6], and, to our best knowledge, this is the first study also focusing on compensation depth variations. Simulation experiments were started with a 50,000 year spin-up to 1750 A.D. (at steady state). This state was characterised by an atmospheric pCO2 of 277 ppm, a CSH depth of 3350 m and a CCD of 4300 m (in the Indo-Pacific, which can be considered the most representative reservoir for the global ocean). In all experiments, we found that CCD variations were considerably greater than CSH variations. The 500 GtC emission scenario yielded CSH and CCD maximum shoalings of 450 and 800 m, respectively, in the year 3400 A.D. about; with the 4240 GtC emission scenario, both CSH and CCD became shallower than 500 m in 2650 A.D. With the highly optimistic S350 stabilisation scenario, CSH and CCD become even shallower than with the 500 GtC emission scenario (650 m and 1000 m shoaling, respectively), although in the year 5000 A.D. only. For the close-to-CO2-doubling scenario S550, CSH and CCD shoaled by about 1950 and 2450 m (to depths of 1400 and 1900 m, respectively). As a result, most of the sea-floor environment bathed in water that was highly corrosive to carbonate material. In the S650 and S750 scenarios experiments, the CCD becomes shallower than 500 m, leaving little space for benthic carbonate producers to survive. [1] Munhoven (2007) Deep-Sea Res. II 54, 722-746. [2] Bacastow and Dewey (1996) Energy Convers. Mgmt. 37, 1079-1086. [3] IPCC (1994) Climate Change 1994, Cambridge University Press. [4] Caldeira and Wickett (2003) Nature 425, 325-325. [5] Orr et al. (2005) Nature 437, 681-686. [6] Cao and Caldeira (2008) Geophys. Res. Lett. 35, L19609. [less ▲]

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See detailThe future European standard to determine odour in ambient air by using field inspection
Guillot, Jean-Michel; Bilsen, Ilse; Both, Ralph et al

in Proceedings of the 4th IWA specialized conference on odours and VOCs, Vitoria, Brazil, 17-21 October, 2011. (2011, October)

This paper presents the methodologies to determine odour in ambient air by field inspection that will be a new European standard. The objective is to characterize the odour in a defined area. Without ... [more ▼]

This paper presents the methodologies to determine odour in ambient air by field inspection that will be a new European standard. The objective is to characterize the odour in a defined area. Without making a link with potential annoyance due to the presence of odours, the described methods propose the way to characterize an exposed environment. Two approaches are defined in the new standard: the grid method and the plume method. The grid method can be used determine the exposure to ambient odours in a defined area of study, using direct observation of recognizable odours in the field by human panel members. This method must be applied over a sufficiently long period of time (6 or 12 months) to be representative for the meteorological conditions of that location. The result is the distribution of the frequency of exposure to odours within the assessment area. The plume method can be used to determine the extent of detectable and recognizable odours from a specific source using direct observation in the field by human panel members under specific meteorological conditions. [less ▲]

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See detailThe future in the present: "entangled temporalities" and religious life in the Kimbanguist church
Melice, Anne ULg; Sarró, Ramon

Conference (2011, December 09)

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See detailFuture ocean carbon cycle: a study of feedbacks with the LOVECLIM model
Mouchet, Anne ULg; Driesschaert, E.; Brovkin, V. et al

Poster (2006, February)

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See detailThe Future of Belgian Federalism through the Eyes of the Citizens
Reuchamps, Min ULg

Conference (2009, September 12)

The Future of Belgian Federalism is definitely a hot topic in Belgian politics but also in citizens’ daily life. Indeed, citizens do talk about it and wonder – and sometimes try to predict – how the ... [more ▼]

The Future of Belgian Federalism is definitely a hot topic in Belgian politics but also in citizens’ daily life. Indeed, citizens do talk about it and wonder – and sometimes try to predict – how the future of Belgium will be. Yet, we only know their attitudes on this important topic through surveys either undertaken by the media or by social scientists. Thus far, no endeavour has been done to study thoroughly and qualitatively citizens’ preferences for the future of their country. In this paper, I propose to offer a first attempt of such an analysis relying on data collected in two small citizens’ panels about the future of Belgian federalism. These two deliberative events were held in Liege (French-speaking Belgium) in September 2007 and in Antwerp (Dutch-speaking Belgium) in October 2008 and gathered respectively 64 and 23 citizens from a variety of backgrounds. During one day, the participants talked about the future of Belgian federalism with fellow citizens in focus groups as well as with politicians and experts; in addition, they answered a pre- and a post-questionnaire. Following Max Weber’s advice to construct ideal type as a way to apprehend the reality and to foster comparisons, types of citizens are constructed on the basis of the data collected in Liège and in Antwerp. While four types of French-speaking are drawn from the former – the unitarist, the unionist, the federalist, and the regionalist –, five emerge from the latter – the unitarist, the unionist, the federalist, the regionalist, and the separatist/independentist. These different types are defined in terms of the citizens’ perceptions and preferences as well as the congruence that followed the learning and deliberative process that occurred throughout the panel. Above all, the types can be compared within the panel and between the panels. In this fashion the future of Belgian federalism can be explored through the eyes of the citizens. [less ▲]

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See detailThe Future of Belgium
Reuchamps, Min ULg

Conference (2011, April 14)

Issues for discussion: 1) Two peoples claiming the same real estate? A Brussels which is 90% Francophone and cradle of the Flemish cultural heritage. The ‘droit du sol’ vs ‘droit des gens’. 2) A conflict ... [more ▼]

Issues for discussion: 1) Two peoples claiming the same real estate? A Brussels which is 90% Francophone and cradle of the Flemish cultural heritage. The ‘droit du sol’ vs ‘droit des gens’. 2) A conflict between linguistic communities? or a cultural divide between Neo-liberal Anglo-Saxon culture in the North and Continental dirigisme in the South? 3) Has Romantic nationalism of the Flemish separatist movement truly been supplanted by ‘Nationalists with Calculators’? 4) The position of the monarchy and the traditional elites in the growing social and political crisis. 5) The EU as unwitting facilitator of the Continent’s cascading self-determinations: the alignment of Bart de Wever’s most populous party in Flanders with an EU identity [less ▲]

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See detailThe future of glycaemic control in critically ill patients requires a close collaboration between bio-engineers and clinicians
Preiser, JC; Desaive, Thomas ULg; Chase, JG

in Proceedings of CONTROL 2010 (2010)

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See detailThe Future of Identity
Burkitt, Katharine ULg

Book published by University of Sallford (2005)

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See detailThe future of microbiology
MELIN, Pierrette ULg

Scientific conference (2011, October 15)

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