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See detailUniversité d'été du CIFEN - Atelier 2 :Tâches complexes dans les formations professionnalisantes
Francois, Nathalie ULiege; Simons, Germain ULiege

Conference (2017, August 25)

Introduction et synthèse de l'atelier consacré aux tâches complexes dans les sections professionnalisantes de différents niveaux d'enseignement en Fédération Wallonie Bruxelles.

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See detailPrésentation de la thématique de recherche et du programme de la journée
Simons, Germain ULiege

Conference (2017, August 25)

Dans cette introduction, G. Simons montre comment la notion de "tâche complexe" s'est construite progressivement en Communauté française de Belgique depuis le Décret "Missions". Ensuite il propose ... [more ▼]

Dans cette introduction, G. Simons montre comment la notion de "tâche complexe" s'est construite progressivement en Communauté française de Belgique depuis le Décret "Missions". Ensuite il propose différentes questions qui baliseront la réflexion tout au long de la journée. Enfin, il présente le programme du colloque et remercie toutes les personnes qui ont contribué à son organisation. [less ▲]

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See detailFragmentation index of DNA sperm in llama semen (Lama glama)
Cucho, Hernan; Ordonez, Cesar; Ampuero, Enrique et al

Poster (2017, August 25)

DNA fragmentation of spermatozoa is an important indicator of seminal quality and fertility. The quality of the genetic information contained in the DNA molecule transmitted by the spermatozoa is ... [more ▼]

DNA fragmentation of spermatozoa is an important indicator of seminal quality and fertility. The quality of the genetic information contained in the DNA molecule transmitted by the spermatozoa is important for the proper development of the embryo. In humans it has been shown that there is a significant correlation between sperm DNA damage and oocyte fertilization, embryo quality, development to blastocyst and embryo implantation. The objective of this study was to analyze the fragmentation of DNA sperm in llama semen collected by post-copulation vaginal aspiration. The collection of 4 llamas was performed on three occasions per animal. The volume, motility, concentration, vitality, sperm membrane functionality assessed with the Integrated Semen Analysis System - ISAS®. The DNA fragmentation index was tested with the Halomax system ®(Halotech company). Volume, motility, vitality and sperm concentration respectively were 1.3 ± 0.8 ml, 12.30 ± 2.02%; 64.69 ± 11.39% and 183.55 ± 28.48 x 106 spz/ml. The functionality of the sperm membrane was 64.95 ± 11.63% and sperm DNA fragmentation index 11.58 ± 13.25%. The values of these different parameters indicate the high quality of the collected semen. [less ▲]

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See detailHigh-resolution reconstruction of 8.2 ka event recorded in Belgian Holocene speleothems
Allan, Mohammed ULiege; verhyden, sophie; Fagel, Nathalie ULiege

Scientific conference (2017, August 24)

Two abrupt shifts in d18O and trace element contents of a stalagmite from the northwestern European continent (southern Belgium) suggest that two cold anomalies occurred beginning at 8.4±0.04 and ending ... [more ▼]

Two abrupt shifts in d18O and trace element contents of a stalagmite from the northwestern European continent (southern Belgium) suggest that two cold anomalies occurred beginning at 8.4±0.04 and ending at 8.15±0.03, possibly reflecting climatic effects associated with the 8.2 ka event. The younger of the two anomalies lasted about 30 years, from 8.18 to 8.15±0.03 ka, with a maximum d18O amplitude of 1.4‰. Trace element (Sr, Ba and Mg) peaks coincide with this second drop of d18O. The anomaly initiation is marked by Sr, Ba and Mg concentration peaks suggesting drier conditions during the coldest years, consistent with previous research in the North Atlantic. The earlier anomaly in trace element, d18O records is associated with generally cold but wet conditions at 8.4 ka, lasted 50 years, and ended abruptly. The interval from 8.4 ka to 8.15 ka was less favorable for speleothem deposition, with denser speleothem calcite deposition and lower growth rate, consistent with a cold, dry climate. The clear recovery in both temperature and rainfall between after both anomalies (8.2 and 8.4 ka), suggests that these anomalies are distinct, and may represent two episodes of AMOC weaking related to the drainage of proglacial lakes Agassiz and Ojibway. [less ▲]

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See detailL'écrit et l'oral réflexifs : un tissage heuristique
Scheepers, Caroline ULiege

in Fischer, Carole; Gagnon, Roxane; De Piétro, Jean-François (Eds.) L'oral aujourd'hui : perspectives didactiques (2017)

La présente contribution envisage l’oral réflexif tel qu’il se décline dans les journaux des apprentissages. Dans plusieurs classes d’école primaire ou secondaire, en France, en Belgique, au Québec, au ... [more ▼]

La présente contribution envisage l’oral réflexif tel qu’il se décline dans les journaux des apprentissages. Dans plusieurs classes d’école primaire ou secondaire, en France, en Belgique, au Québec, au cours ou au terme de leur journée de classe, des élèves prennent la plume pour écrire dans un cahier à propos de leurs apprentissages, de leurs difficultés, de leurs incompréhensions, de leurs stratégies d’apprentissage, de leurs modes de résolution de problèmes, mais aussi à propos des relations interpersonnelles nouées à l’école, des tâches prescrites par l’enseignant ou de ses pratiques pédagogiques. Tout aussi inlassablement, les enseignants dialoguent avec les enfants en commentant, interrogeant, discutant les annotations des scripteurs dans leur cahier. Ils lisent et écrivent, ils réajustent les projets pédagogiques en fonction des textes lus. Au début de la journée, un enfant est invité à lire devant la classe le texte qu’il a rédigé la veille. Les pairs et l’enseignant écoutent le texte ainsi livré à tous, ils le commentent le cas échéant. On le voit, le dispositif du journal d’apprentissage associe étroitement oral et écrit réflexifs. Cette contribution s’attachera à dégager l’articulation du scriptural et de l’oral au cœur et autour du journal des apprentissages. Nous tenterons d’abord de mieux cerner le genre « journal des apprentissages » sur le plan des pratiques langagières orales et scripturales qu’il sollicite et contribue à construire chez l’élève. Nous verrons si une délimitation nette peut être tracée entre les unes et les autres. Ensuite, nous analyserons les annotations des scripteurs consacrées aux tâches orales réalisées en classe, ce qui permettra d’identifier comment l’oral est mobilisé ou enseigné dans les classes de l’échantillon, mais aussi d’analyser la réception des activités orales auprès des apprenants. Notre corpus est international et compte près de deux-cents journaux tenus par des enfants du primaire et des adolescents du secondaire, dans des contextes contrastés. [less ▲]

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See detailPreservation protocol for dimethylsulfoniopropionate and dimethylsulfoxide analysis in plant material of the Mediterranean seagrass Posidonia oceanica, and re-evaluation of dimethylsulfoniopropionate leaf content
Borges, Alberto ULiege; Champenois, Willy ULiege

in Aquatic Botany (2017), 143C

We tested three treatments to preserve Posidonia oceanica leaves for the analysis of dimethylsulfoniopropionate (DMSP) and dimethylsulfoxide (DMSO): oven dried at 60 °C for 24 h, frozen at −20 °C, and ... [more ▼]

We tested three treatments to preserve Posidonia oceanica leaves for the analysis of dimethylsulfoniopropionate (DMSP) and dimethylsulfoxide (DMSO): oven dried at 60 °C for 24 h, frozen at −20 °C, and frozen-in-ice and kept at −20 °C. The DMSP content was analyzed by proxy as dimethylsulfide (DMS) by gas chromatography after alkaline cleavage at room-temperature. The DMSP leaf content of P. oceanica in samples that were oven dried at 60 °C for 24 h, then stored at room temperature decreased by 87% over 80 days of storage and then remained stable for about 88 additional days compared to the control. The DMSO leaf content of P. oceanica in samples that were oven dried increased nine-fold after 198 days of storage following drying compared to the control. Both the DMSP and DMSO leaf content of P. oceanica remained stable for 198 days compared to the control with frozen and frozen-in-ice treatments, which we both recommend as adequate protocols to preserve P. oceanica tissues for DMS(P,O) analysis. The annual average DMSP leaf content of P. oceanica at 10 m in the Bay of Calvi (Corsica, France) was 205 ± 58 μmol g−1 (fresh weight) based on samples preserved frozen, two orders of magnitude higher than the value we previously reported based on samples that were oven dried. The newly determined DMSP leaf content allows ranking P. oceanica as the highest DMSP producer reported to date among marine and inter-tidal autotrophs. [less ▲]

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See detailSplit-Band Interferometry-Assisted Phase Unwrapping for the Phase Ambiguities Correction
Libert, Ludivine ULiege; De Rauw, Dominique ULiege; d'Oreye, Nicolas et al

in Remote Sensing (2017), 9(9),

Split-Band Interferometry (SBInSAR) exploits the large range bandwidth of the new generation of synthetic aperture radar (SAR) sensors to process images at subrange bandwidth. Its application to an ... [more ▼]

Split-Band Interferometry (SBInSAR) exploits the large range bandwidth of the new generation of synthetic aperture radar (SAR) sensors to process images at subrange bandwidth. Its application to an interferometric pair leads to several lower resolution interferograms of the same scene with slightly shifted central frequencies. When SBInSAR is applied to frequency-persistent scatterers, the linear trend of the phase through the stack of interferograms can be used to perform absolute and spatially independent phase unwrapping. While the height computation has been the main concern of studies on SBInSAR so far, we propose instead to use it to assist conventional phase unwrapping. During phase unwrapping, phase ambiguities are introduced when parts of the interferogram are separately unwrapped. The proposed method reduces the phase ambiguities so that the phase can be connected between separately unwrapped regions. The approach is tested on a pair of TerraSAR-X spotlight images of Copahue volcano, Argentina. In this framework, we propose two new criteria for the frequency-persistent scatterers detection, based respectively on the standard deviation of the slope of the linear regression and on the phase variance stability, and we compare them to the multifrequency phase error. Both new criteria appear to be more suited to our approach than the multifrequency phase error. We validate the SBInSAR-assisted phase unwrapping method by artificially splitting a continuous phase region into disconnected subzones. Despite the decorrelation and the steep topography affecting the volcanic test region, the expected phase ambiguities are successfully recovered whatever the chosen criterion to detect the frequency-persistent scatterers. Comparing the aspect ratio of the distributions of the computed phase ambiguities, the analysis shows that the phase variance stability is the most efficient criterion to select stable targets and the slope standard deviation gives satisfactory results. [less ▲]

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See detailVideo and camera traps to investigate animal ecophysiology and enhance wildlife management: case study on bees and elephants interactions in Gabon.
Ngama, Steeve ULiege; Bindelle, Jérôme ULiege; Vermeulen, Cédric ULiege

Conference (2017, August 23)

Crops are often sources of conflict between humans and wildlife. Wildlife damage to crops can drastically reduce income, amplifying poverty and creating a negative perception of wild animal conservation ... [more ▼]

Crops are often sources of conflict between humans and wildlife. Wildlife damage to crops can drastically reduce income, amplifying poverty and creating a negative perception of wild animal conservation among rural people. In this context, crop-raiding animals like elephants quickly become “problem animals”. To deter elephants from raiding crops beehives have been successfully employed in East Africa while providing honey for the farmers. Whether such a technique could work on forest elephants (Loxodonta Africana cyclotis) in Central Africa is still unknown. An ecophysiology-based trial consisting on bees and elephants interactions assessment was conducted in Gabon. It aimed to evaluate whether the presence of Apis mellifera adansonii, the African honey bee species present in Central Africa, deters forest elephants from feeding on experimental wild fruit trees. We suspected that bee physiology matters on bee defensive behavior and monitoring it through measuring bee activities can help better understand bees and elephants interactions. For this purpose video cameras were used to record activities of bees in fourteen beehives hung on seven wild trees (4 Irvingia gabonensis and 3 Sacoglottis gabonensis trees) each equipped with a camera trap to record elephants feeding behaviors on those trees. This experimental apparatus was monitored during 70 consecutive weeks from 2012 to 2013. We captured 8151 photos representing 4h31min42s of time spent by elephants at experimental trees and more than 75 videos of bees activities from where we extracted genuine results. Our results show a significant correlation between the effectiveness of beehives as deterrents of elephants and bee activity. Although elephant disturbance of hives does not inhibit honey production, there is a tradeoff between deterrence and the quantity of honey produced. More interestingly, to best achieve the dual goals of deterring elephants and producing honey colonies must maintain an optimum activity level of 40 to 60 bee movements per minute. Thus Apis mellifera adansonii bees can effectively deter elephants but beehives must be actively managed to maintain bees’ colonies at the optimum activity level. [less ▲]

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See detailVariation of tree allometry and aboveground biomass in central African forests
Loubota Panzou, Grâce Jopaul ULiege; Ligot, Gauthier ULiege; Bastin, Jean-François et al

Conference (2017, August 23)

Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ initiative. Many techniques exist to estimate forest ... [more ▼]

Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ initiative. Many techniques exist to estimate forest biomass at different spatial scales, but all ultimately rely on allometric equations calibrated on destructive measurements of individual tree biomass, in order to convert forest inventory data into biomass estimates. For many tropical forest ecosystems, that are structurally complex and species rich, these allometric equations have not yet been developed and general allometric equations are being used instead, with possibly local adjustment of tree allometry with non-destructive data. Variation in height-diameter allometry and in crown-diameter allometry across forest types and environmental conditions have been demonstrated to be of extreme importance for the estimation of biomass and carbon stocks in tropical forests, but yet poorly explored in central Africa. In this study we aimed to determine the variation in tree height-diameter and crown-diameter allometries across central African forests and the consequences for biomass and carbon stocks. Tree allometry data were collected in two of semi-deciduous forest sites in northern Republic of Congo that have vastly different substrate and soils (clay soils on quartzite and sandy soils on sandstone plateau), and forest communities, but similar rainfall regimes. These data will be analyzed to test two hypotheses: (i) tree allometry strongly varies across forest types with contrasted environmental conditions (and specifically soils), and (ii) both allometry and forest structure contributed to the greater biomass of the site on rich soil (quartzite substrate). Our newly collected data for two sites in northern Congo will be confronted to existing allometry and inventory data available elsewhere in the Congo basin to get a broader picture of allometric variations and its consequences for the estimation of biomass and carbon stocks. [less ▲]

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See detailWell-defined polyvinylamine-based copolymers: synthesis by organometallic-mediated radical polymerization and use in gene transfection
Debuigne, Antoine ULiege; Dréan, Mathilde; Detrembleur, Christophe ULiege et al

Conference (2017, August 22)

Polyvinylamine (PVAm) presents valuable properties like affinity for many supports, pH responsiveness, metal binding capacity, polyelectrolytes complexation, and is used in various applications including ... [more ▼]

Polyvinylamine (PVAm) presents valuable properties like affinity for many supports, pH responsiveness, metal binding capacity, polyelectrolytes complexation, and is used in various applications including coatings, water purification or gas membrane separation. PVAm is commonly prepared by free radical polymerization of N-vinyl monomers followed by deprotection and release of the masked amino functions. However, examples of controlled synthesis of polyvinylamine-based copolymers are scarce because of the high reactivity of the propagating radicals deriving from non-conjugated N-vinyl monomers due to the lack of resonance stabilization. The present communication aims at reporting an efficient platform for producing tailor-made PVAms via organometallic-mediated radical polymerization (OMRP) of N-vinylacetamides followed by hydrolysis of the pendent amide moieties. In this case, cobalt(II) acetylacetonate was successfully used as controlling agent. The synthesis of a series of well-defined homopolymers, statistical and block copolymers with pendent primary and/or secondary amines having low dispersities, predictable molar masses and precise compositions, will be described. Finally, we will discuss the possible use of these polyvinylamine-containing copolymers as gene transfection agents. Some of them demonstrated high DNA transfection level in combination with high cell viability. [less ▲]

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See detailGroundless altruism: Why it makes sense to risk one's life for other people's money
Dumitru, Magdalena ULiege; Joergensen, Gitte

Conference (2017, August 22)

In a study where participants were asked to make a series of assessments in distinct circumstances, we show that altruistic agents may incur disadvantages in the name of values they do not believe in (i.e ... [more ▼]

In a study where participants were asked to make a series of assessments in distinct circumstances, we show that altruistic agents may incur disadvantages in the name of values they do not believe in (i.e., saving money) as long as they believe in the overarching category (e.g., it is a ‘good deed’ to recover other people’s money). Whereas previous research mostly targeted ultimate benefits (i.e., whether or not altruistic agents incur real disadvantages), the axiological basis of altruistic acts (i.e., whether or not they have the same worth to self and to others) has remained unchallenged. Here, we explored “groundless altruism” by asking participants to rate their agreement with the statement ‘Money is worth risking my life for’ before and after presenting them with an altruistic scenario. There was a dramatic increase in the proportion of ‘yes’ responses from the first to the second rating. Moreover, as predicted by the cultural group selection theory, the status of the agent (low-rank police employee v s. secret agent) was largely irrelevant. These findings suggest that social constructs such as categorisation have the potential to significantly influence human behaviour in various domains from moral psychology to work ethics to language learning. [less ▲]

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See detailNarrative Misappropriations of Pokémon: How Fanarts and Fanfictions Playfully Feed and Reconfigure a Transmedia Universe
Barnabé, Fanny ULiege

Conference (2017, August 21)

As defined by Jenkins (2006), transmedia storytelling is intimately linked with creative practices of reception which take part in what we now call the “participatory culture” (Raessens, 2005; Jenkins ... [more ▼]

As defined by Jenkins (2006), transmedia storytelling is intimately linked with creative practices of reception which take part in what we now call the “participatory culture” (Raessens, 2005; Jenkins, 1992 and 2009). The audience plays, indeed, a key role in the construction of transmedia universes, given that “to fully experience any fictional world, consumers must assume the role of hunters and gatherers, chasing down bits of the story across media channels, comparing notes with each other via online discussion groups, and collaborating to ensure that everyone who invests time and effort will come away with a richer entertainment experience” (Jenkins, 2006: 21). Consequently, studying a media – in this case, the video game – through the lens of transmedia storytelling urges one to take into consideration how the public can participate, feed, or transform fictions by consuming them. Furthermore, in the field of game studies, it is all the more relevant to deal with the implication of players in the creative process since video games are historically and structurally related to the practice of misappropriation or detournement. As Genvo notes: “the creation of the first video game [Spacewar, 1962] already resulted from a playful act, which was expressed by the misuse of the conventional function of an MIT’s super calculator” (Genvo, 2008: 2). This original affinity now appears in a number of creative practices that prolong the game outside its primary space and enable it to seep into other medias: as fanfictions, modding or machinimas show, the video game is regularly apprehended by players not as a closed work to consume, but “more as [a] suit[e] of resources to be played with” (Newman, 2012: 123). This paper therefore seeks to study the impact of players’ misappropriations on the development of video games' fictional worlds. In this perspective, I will focus on a deeply transmedia license, the Pokémon saga, and on two creative practices that reconfigure games’ universes: fanarts and fanfictions. While amateur drawings and comics inspired by Pokémon GO have created narrative extensions from scratch about the barely characterized Team Leaders (Blanche, Candela and Spark), fan-authors have written thousands of texts that play with elements of the Pokémon universe in order to produce original stories. Yet, these textual and pictorial rewritings do not merely reuse narrative elements of Pokémon games; they also feature strictly playful components such as gameplay, glitches or actions like saving and reloading, which then become new types of narrative motifs. Fanfictions and fanarts thus construct – like the games they extend – hybrid fictions, mixing storytelling and gaming logic: in Amato’s words, “ludiegesis” (Amato, 2005 : 301). Using theoretical tools from narratology and from game studies, I will show that, by reincorporating playful aspects in their narrative structures, these derivative works hold a reflexive discourse on the original game that cannot be reduced to a binary opposition between “adhesion” and “subversion”, but which builds a whole new stratum of fiction. [less ▲]

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See detailCO2-sourced α-alkylidene cyclic carbonates: a Step forward in the quest for functional regioregular poly(urethane)s and poly(carbonate)s
Gennen, Sandro ULiege; Grignard, Bruno ULiege; Tassaing, Thierry et al

in Angewandte Chemie International Edition (2017), 56(35), 1039410398

We describe a robust platform for the synthesis of a large diversity of novel functional CO2 -sourced polymers by exploiting the regio-controlled and site selective ring-opening of α- alkylidene ... [more ▼]

We describe a robust platform for the synthesis of a large diversity of novel functional CO2 -sourced polymers by exploiting the regio-controlled and site selective ring-opening of α- alkylidene carbonates by various nucleophiles. The remarkable reactivity of α-alkylidene carbonates is dictated by the exocyclic olefinic group that selectively orients the cyclic carbonate ring- opening with the formation of an enol species. The polyaddition of CO2 -sourced bis-α-alkylidene carbonates (bis-αCCs) with primary and secondary diamines provides novel regioregular functional poly(urethane)s. The reactivity of bis-αCCs is also exploited for producing new poly(β-oxo-carbonate)s by organocatalyzed polyaddition with a diol. All polyadditions were feasible under ambient conditions. This synthesis platform provides new functional variants of world-class leading polymers families (polyurethanes, polycarbonates) and valorises CO2 as a chemical feedstock. [less ▲]

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See detailMicrobiological stability of rice tart stored at ambient temperature after baking
N'guessan, Elise; Cissé, Mohamed; Niyonzima, Eugene ULiege et al

in Journal of Food Research (2017), 6(5), 41-49

Very popular in Belgium, rice tart is a hot pastry sold in bakeries. It is then consumed at home, for dessert or snack. This study is conducted to investigate the microbiological stability of this ... [more ▼]

Very popular in Belgium, rice tart is a hot pastry sold in bakeries. It is then consumed at home, for dessert or snack. This study is conducted to investigate the microbiological stability of this foodstuff, from the end of baking to end user by consumers. In this purpose, 108 rice tart samples were collected from each of seven bakeries in five Belgium provinces. Physico-chimical analysis in addition to microbiological analysis were carried out in accordance with the European Regulation EC 2073/2005 and with references methods, to enumerate the total microorganisms count, Staphylococcus aureus, Bacillus cereus as well as Enterobacteria, susceptible likely to contaminate the tarts during the production or after baking. Even when the results meet the microbiological safety standards immediately after baking in all bakeries implicated, a significant (p <0,05) increase of mesophilic aerobic bacteria (ranging from <1 to 7 log cfu/g) and B. cereus (> 3,7 log cfu/g) was observed during the storage at non refrigerated temperature (28 to 30°C). A post-baking recontamination and other parameters like an insufficient baking time or a non uniform distribution of the oven heat could explain the observed bacteria growth. The present study shows that most rice tarts investigated are microbiologically safe. However, the possible increase of bacteria load in this foodstuff attributable to the favorable aw, pH and temperature conditions, highlight the importance of applying good hygienic practices and compliance with storage conditions after baking to ensure consumer safety. [less ▲]

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See detailGestion de la biodiversité
Monty, Arnaud ULiege

Conference (2017, August 21)

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See detailNanofitin as a New Molecular-Imaging Agent for the Diagnosis of 2 Epidermal Growth Factor Receptor Over-Expressing Tumors.
Goux, Marine; Becker, Guillaume ULiege; Gorré, Harmony et al

in Bioconjugate Chemistry (2017), 28(9), 2361-2371

Epidermal growth-factor receptor (EGFR) is involved in cell growth and proliferation and is over-expressed in malignant tissues. Although anti-EGFR-based immunotherapy became a standard of care for ... [more ▼]

Epidermal growth-factor receptor (EGFR) is involved in cell growth and proliferation and is over-expressed in malignant tissues. Although anti-EGFR-based immunotherapy became a standard of care for patients with EGFR-positive tumors, this strategy of addressing cancer tumors by targeting EGFR with monoclonal antibodies is less-developed for patient diagnostic and monitoring. Indeed, antibodies exhibit a slow blood clearance, which is detrimental for positron emission tomography (PET) imaging. New molecular probes are proposed to overcome such limitations for patient monitoring, making use of low-molecular-weight protein scaffolds as alternatives to antibodies, such as Nanofitins with better pharmacokinetic profiles. Anti-EGFR Nanofitin B10 was reformatted by genetic engineering to exhibit a unique cysteine moiety at its C-terminus, which allows the development of a fast and site-specific radiolabeling procedure with 18F−4-fluorobenzamido-N-ethylamino-maleimide (18F−FBEM). The in vivo tumor targeting and imaging profile of the anti-EGFR Cys−B10 Nanofitin was investigated in a double-tumor xenograft model by static small-animal PET at 2 h after tail-vein injection of the radiolabeled Nanofitin 18F−FBEM−Cys−B10. The image showed that the EGFR- positive tumor (A431) is clearly delineated in comparison to the EGFR-negative tumor (H520) with a significant tumor-to-background contrast. 18F−FBEM−Cys−B10 demonstrated a significantly higher retention in A431 tumors than in H520 tumors at 2.5 h post-injection with a A431-to-H520 uptake ratio of 2.53 ± 0.18 and a tumor-to-blood ratio of 4.55 ± 0.63. This study provides the first report of Nanofitin scaffold used as a targeted PET radiotracer for in vivo imaging of EGFR-positive tumor, with the anti-EGFR B10 Nanofitin used as proof-of-concept. The fast generation of specific Nanofitins via a fully in vitro selection process, together with the excellent imaging features of the Nanofitin scaffold, could facilitate the development of valuable PET-based companion diagnostics. [less ▲]

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See detailIn vivo chlorophyll fluorescence screening allows the isolation of a Chlamydomonas mutant defective for NDUFAF3, an assembly factor involved in mitochondrial complex I assembly
Massoz, Simon; Hanikenne, Marc ULiege; Bailleul, Benjamin et al

in Plant Journal (The) (2017), 17(8), 2045-2054

The qualitative screening method to select complex I mutants in the microalga Chlamydomonas, based on reduced growth under heterotrophic condition, is not suited for high throughput screening. In order to ... [more ▼]

The qualitative screening method to select complex I mutants in the microalga Chlamydomonas, based on reduced growth under heterotrophic condition, is not suited for high throughput screening. In order to develop a fast screening method based on measurements of chlorophyll fluorescence, we first demonstrated that complex I mutants displayed decreased photosystem II efficiency in the genetic background of a photosynthetic mutation leading to reduced formation of the electrochemical proton gradient in the chloroplast (pgrl1 mutation). In contrast, single mutants (complex I and pgrl1 mutants) could not be distinguished from wild type by their photosystem II efficiency in the tested conditions. We next performed an insertional mutagenesis on the pgrl1 mutant. Out of ~3000 hygromycin-resistant insertional transformants, 46 had decreased photosystem II efficiency and three were complex I mutants. One of the mutants was tagged and whole genome sequencing identified the resistance cassette in NDUFAF3, a homolog of the human NDUFAF3 gene, encoding for an assembly factor involved in complex I assembly. Complemented strains showed restored complex I activity and assembly. Overall, we described here a screening method which is fast and particularly suited for identification of Chlamydomonas complex I mutants. [less ▲]

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See detailLandscape and hydrological controls on the downstream transport of dissolved organic matter in the Congo and Zambezi rivers
Lambert, T; Bouillon, S; Teodoru, CR et al

Conference (2017, August 20)

Detailed reference viewed: 17 (2 ULiège)