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See detailInduction of photosynthetic electron transfer upon anoxia in Chlamydomonas: role of hydrogenase activity and PSI-cyclic electron flow
Godaux, Damien ULg; Berne, Nicolas ULg; Remacle, Claire ULg et al

Poster (2013)

In Chlamydomonas reinhardtii, anoxic environment leads to the expression of various fermentative/anaerobic pathways. Among them, oxygen-sensitive hydrogenases catalyze the reduction of protons from ... [more ▼]

In Chlamydomonas reinhardtii, anoxic environment leads to the expression of various fermentative/anaerobic pathways. Among them, oxygen-sensitive hydrogenases catalyze the reduction of protons from reduced ferredoxin resulting in the production of molecular hydrogen. A possible role of chloroplast hydrogenase in the anaerobic induction of photosynthesis has been suggested forty years ago (Kessler, 1973) but never further explored. H2 evolution is a minor and transient phenomenon which is often considered as a safety mechanism to protect photosynthetic chain from overreduction (Melis and Happe, 2001; Hemschemeier et al., 2009). Recent data about hydrogen production in a pgrl1 (Proton Gradient Regulation like1) mutant with limited capacity for PSI-cyclic electron flow (CEF) also suggested a participation of CEF in photosynthesis reactivation after short dark-anoxic periods (Tolleter et al., 2011). Because H2 evolution is improved in pgrl1 mutant, authors came to the conclusion that H+ gradient generated by CEF strongly prevents electron supply to the hydrogenase and is thus a limitating factor for hydrogen production. The aim of our work is to further study the role of hydrogenase and CEF in the photosynthesis reactivation process after short (~1h) or long (>18h) dark-anoxic periods. We take advantage of the availability of hydrogenase-deficient mutants (hydEF, hydG) (Posewitz et al., 2005; Godaux et al., 2013) and above-mentioned CEF-deficient pgrl1 mutant. Light-induced photosynthetic electron transfer is studied by measuring hydrogen and oxygen evolution, as well as by following kinetics of chlorophyll fluorescence emission and P700 oxidoreduction. Firstly, we show that during the induction of photosynthesis after long dark-anoxic periods, there is a linear relationship between hydrogen evolution, PSI and PSII activities, meaning that an hydrogenase- dependent photosynthetic linear electron flow (LEF) mainly operates. Moreover, PSI and PSII photochemical yield are almost null in hydrogenase-deficient mutants. We conclude that hydrogenase is the main sink for photosynthetic electrons upon illumination after prolonged anoxia. Similarly, a linear correlation can be established between hydrogen evolution, hydrogenase expression/activity, and PSI or PSII photochemical yields upon adaptation to anoxia. In the next part of our work, we focus our attention on the role of PSI-CEF in the induction of photosynthesis upon anoxia. Combined measurements of PSI/PSII activities and O2/H2 evolution show that induction of photosynthesis is delayed in a Pgrl1-deficient strain. In absence of Pgrl1 protein, the H+ gradient is also lower and we thus propose that a lack of ATP is responsible for the delayed Calvin cycle reactivation, so that hydrogen production can be achieved for a longer time without inactivation of hydrogenase activity by evolved O2. These results are in good agreement with other results obtained by our group, demonstrating that state transition is a critical process for induction of photosynthesis in anoxia (Ghysels et al., accepted). In conclusion, a Pgrl1-dependent CEF seems to be in first importance to photosynthesis induction after one hour of dark-anaerobiosis adaptation, acting together with an hydrogenase dependant LEF to set favourable conditions for Calvin cycle activation. [less ▲]

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See detailInduction of potato (Solanum tuberosum L.) tuber sprouting by hydrogen peroxide.
Bajji, M.; M'Hamdi, M.; Gastiny, F. et al

in Free Radical Research (2003), 37

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See detailInduction of protective immunity to bovine herpesvirus type 1 in cattle by intranasal administration of replication-defective human adenovirus type 5 expressing glycoprotein gC or gD
Gogev, S.; Vanderheijden, N.; Lemaire, Mylène et al

in Vaccine (2002), 20(9-10), 1451-1465

Replication-defective human adenoviruses type 5 (HAd5) expressing the bovine herpesvirus type 1 (BHV-1) glycoprotein gC or gD under the control of the human cytomegalovirus immediate-early promoter ... [more ▼]

Replication-defective human adenoviruses type 5 (HAd5) expressing the bovine herpesvirus type 1 (BHV-1) glycoprotein gC or gD under the control of the human cytomegalovirus immediate-early promoter/enhancer (AdCMVgC or AdCMVgD) or the 5' regulatory region of the human desmin gene (AdDESMgC or AdDESMgD) were generated. A preliminary experiment performed on rabbits showed that the intranasal administration of AdCMV elicited higher levels of BHV-1 neutralizing antibodies than the intramuscular administration of AdDESM. The obtained results allowed to select the replication-defective AdCMVgC and AdCMVgD for further assessment of their potential as a recombinant vaccine in cattle. Calves were injected intranasally twice 3 weeks apart with either AdCMVgC or AdCMVgD or a combination of these two recombinants or a commercially available live vaccine for comparison. The highest BHV-1 neutralizing antibody titres were obtained with AdCMVgD followed by the live vaccine and to a lower extent with the combination of the two recombinants (AdCMVgC+AdCMVgD). Calves were protected against intranasal BHV-1 challenge performed 3 weeks after the second immunization. In view of the obtained results, recombinant HAd5 may be developed as an intranasal vaccine vector in cattle administrated either alone or sequentially with non-human adenovirus-based vectors. [less ▲]

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See detailInduction of Sparc by Vegf in Human Vascular Endothelial Cells
Kato, Y.; Lewalle, J. M.; Baba, Y. et al

in Biochemical and Biophysical Research Communications (2001), 287(2), 422-6

SPARC/osteonectin/BM-40 is a matricellular protein that is thought to be involved in angiogenesis and endothelial barrier function. Previously, we have detected high levels of SPARC expression in ... [more ▼]

SPARC/osteonectin/BM-40 is a matricellular protein that is thought to be involved in angiogenesis and endothelial barrier function. Previously, we have detected high levels of SPARC expression in endothelial cells (ECs) adjacent to carcinomas of kidney and tongue. Although SPARC-derived peptide showed an angiogenic effect, intact SPARC itself inhibited the mitogenic activity of vascular endothelial growth factor (VEGF) for ECs by the inhibiting phosphorylation of flt-1 (VEGF receptor 1) and subsequent ERK activation. Thus, the role of SPARC in tumor angiogenesis, stimulation or inhibition, is still unclear. To clarify the role of SPARC in tumor growth and progression, we determined the effect of VEGF on the expression of SPARC in human microvascular EC line, HMEC-1, and human umbilical vein ECs. VEGF increased the levels of SPARC protein and steady-state levels of SPARC mRNA in serum-starved HMEC-1 cells. Inhibitors (SB202190 and SB203580) of p38, a mitogen-activated protein (MAP) kinase, attenuated VEGF-stimulated SPARC production in ECs. Since intact SPARC inhibits phosphorylation ERK MAP kinase in VEGF signaling, it was suggested that SPARC plays a dual role in the VEGF functions, tumor angiogenesis, and extravasation of tumors mediated by the increased permeability of endothelial barrier function. [less ▲]

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See detailInduction of superovulation in cattle
Beckers, Jean-François ULg; Wouters-Ballman, P.; Viviers-Donnay, I. et al

Conference (1987, September 04)

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See detailInduction of superovulation in domestic ruminants
Gonzalez, F.; Calero, P.; Beckers, Jean-François ULg

in Renaville, R.; BurnY, A. (Eds.) Biotechnology in Animal Husbandry (2001)

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See detailInduction of the 27-kDa heat shock protein (Hsp27) in the rat medulla oblongata after vagus nerve injury.
Hopkins, D. A.; Plumier, Jean-Christophe ULg; Currie, R. W.

in Experimental Neurology (1998), 153(2), 173-83

The 27-kDa heat shock protein (Hsp27) is constitutively expressed in motor and sensory neurons of the brainstem. Hsp27 is also rapidly induced in the nervous system following oxidative and cellular ... [more ▼]

The 27-kDa heat shock protein (Hsp27) is constitutively expressed in motor and sensory neurons of the brainstem. Hsp27 is also rapidly induced in the nervous system following oxidative and cellular metabolic stress. In this study, we examined the distribution of Hsp27 in the rat medulla oblongata by means of immunohistochemistry after the vagus nerve was cut or crushed. After vagal injury, rats were allowed to survive for 6, 12, 24 h, 2, 4, 7, 10, 14, 30, or 90 days. Vagus nerve lesions resulted in a time-dependent up-regulation of Hsp27 in vagal motor and nodose ganglion sensory neurons that expressed Hsp27 constitutively and de novo induction in neurons that did not express Hsp27 constitutively. In the dorsal motor nucleus of the vagus nerve (DMV) and nucleus ambiguus, the levels of Hsp27 in motor neurons were elevated within 24 h of injury and persisted for up to 90 days. Vagal afferents to the nucleus of the tractus solitarius (NTS) and area postrema showed increases in Hsp27 levels within 4 days that were still present 90 days postinjury. In addition, increases in Hsp27 staining of axons in the NTS and DMV suggest that vagus nerve injury resulted in sprouting of afferent axons and spread into areas of the dorsal vagal complex not normally innervated by the vagus. Our observations are consistent with the possibility that Hsp27 plays a role in long-term survival of distinct subpopulations of injured vagal motor and sensory neurons. [less ▲]

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See detailInduction of the adrenoleukodystrophy-related gene (ABCD2) by thyromimetics
Genin, Emmanuelle ULg; Gondcaille, Catherine; Trompier, Doriane et al

in Journal of Steroid Biochemistry & Molecular Biology (2009), 116 (1-2)

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by mutations in the ABCD1 (ALD) gene. The ABCD2 gene, its closest homolog, has been shown to compensate for ABCD1 deficiency when ... [more ▼]

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by mutations in the ABCD1 (ALD) gene. The ABCD2 gene, its closest homolog, has been shown to compensate for ABCD1 deficiency when overexpressed. We previously demonstrated that the ABCD2 promoter contains a functional thyroid hormone response element. Thyroid hormone (T3) through its receptor TRbeta can induce hepatic Abcd2 expression in rodents and transiently normalize the VLCFA level in fibroblasts of Abcd1 null mice. In a therapeutic perspective, the use of selective agonists of TRbeta should present the advantage to be devoid of side effects, at least concerning the cardiotoxicity associated to TRalpha activation. In this study, we compared the effects of T3 with those of two thyromimetics (GC-1 and CGS 23425) specific of TRbeta. Using a gene reporter assay, we demonstrated that the rat Abcd2 promoter responds to the thyromimetics in a dose-dependent way similar to what is observed with T3. We then investigated the effects of 2-, 4- and 10-day treatments on the expression of ABCD2 and its paralogs ABCD3 and ABCD4 in human cell lines by RT-qPCR. Both thyromimetics trigger up-regulation of ABCD2-4 genes in HepG2 cells and X-ALD fibroblasts. Interestingly, in X-ALD fibroblasts, while T3 is associated with a transient induction of ABCD2 and ABCD3, the treatments with thyromimetics allow the induction to be maintained until 10 days. Further in vivo experiments in Abcd1 null mice with these thyromimetics should confirm the therapeutic potentialities of these molecules. [less ▲]

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See detailInduction of the Alternative NF-{kappa}B Pathway by Lymphotoxin {alpha}{beta} (LT{alpha}{beta}) Relies on Internalization of LT{beta} Receptor
Ganeff, Corine; Remouchamps, Caroline ULg; Boutaffala, Layla et al

in Molecular & Cellular Biology (2011), 21

Several tumor necrosis factor receptor (TNFR) family members activate both the classical and the alternative NF-κB pathways. However, how a single receptor engages these two distinct pathways is still ... [more ▼]

Several tumor necrosis factor receptor (TNFR) family members activate both the classical and the alternative NF-κB pathways. However, how a single receptor engages these two distinct pathways is still poorly understood. Using lymphotoxin β receptor (LTβR) as a prototype, we showed that activation of the alternative, but not the classical, NF-κB pathway relied on internalization of the receptor. Further molecular analyses revealed a specific cytosolic region of LTβR essential for its internalization, TRAF3 recruitment, and p100 processing. Interestingly, we found that dynamin-dependent, but clathrin-independent, internalization of LTβR appeared to be required for the activation of the alternative, but not the classical, NF-κB pathway. In vivo, ligand-induced internalization of LTβR in mesenteric lymph node stromal cells correlated with induction of alternative NF-κB target genes. Thus, our data shed light on LTβR cellular trafficking as a process required for specific biological functions of NF-κB. [less ▲]

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See detailInduction of Thymocyte Proliferation by Supernatants from a Mouse Thymic Epithelial Cell Line
Villa-Verde, Dea; Defresne, Marie-Paule ULg; Greimers, Roland ULg et al

in Cellular Immunology (1991), 136(1), 113-21

The thymic stroma plays a critical role in the generation of T lymphocytes by direct cell-to-cell contacts as well as by secreting growth factors or hormones. The thymic epithelial cells, responsible for ... [more ▼]

The thymic stroma plays a critical role in the generation of T lymphocytes by direct cell-to-cell contacts as well as by secreting growth factors or hormones. The thymic epithelial cells, responsible for thymic hormone secretion, include morphologically and antigenically distinct subpopulations that may exert different roles in thymocyte maturation. The recent development of thymic epithelial cell lines provided an interesting model for studying thymic epithelial influences on T cell differentiation. Treating mouse thymocytes by supernatants from one of TEC line (IT-76M1), we observed an induction of thymocyte proliferation and an increase in the percentages of CD4-/CD8- thymocytes. This proliferation was largely inhibited when thymocytes were incubated with IT-76M1 supernatants together with an anti-thymulin monoclonal antibody, but could be enhanced by pretreating growing epithelial cells by triiodothyronine. We suggest that among the target cells for thymulin within the thymus, some putative precursors of early phenotype might be included. [less ▲]

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See detailInduction of tissue resorption in echinoderms
Dubois, P.; Bureau, Fabrice ULg; Gyoot, M.

Poster (1993)

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See detailInduction of tissue resorption in globiferous pedicellariae of the echinoid Sphaerechinus granularis
Dubois, P.; Ghyoot, M.; Bureau, Fabrice ULg

in David, B.; Guille, A.; Féral, J.-P. (Eds.) et al Echinoderms Through Time (1994)

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See detailInduction-Déduction en anthropologie
Strivay, Lucienne ULg; Genard, Jean-Louis

Conference (2008, May 16)

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See detailAn inductive and opportunistic detection of a pedagogical pattern in a 17 online course sample
Verpoorten, Dominique ULg; Poumay, Marianne ULg; Delcomminette, Séverine ULg et al

in Proceedings of the European Distance Education Network (2006)

LabSET (Support Lab for Telematic Learning – University of Liège, Belgium) applied a pedagogical pattern detection process on 17 online courses designed by faculty. The analysis unearths 11 instances of ... [more ▼]

LabSET (Support Lab for Telematic Learning – University of Liège, Belgium) applied a pedagogical pattern detection process on 17 online courses designed by faculty. The analysis unearths 11 instances of an activity structure named here RQAT (Reading-Questions/Answers-Test) which offers an alternative (among others) to the conventional lecturing, still extensively practiced in higher education. The recurrence and the relative invariance of the RQAT learning design legitimated an attempt to format it as a pedagogical pattern, used within LabSET's missions of teacher professional development. The conceptual documentation of RQAT suggests also an "illustration" of the pattern and its linkage to a taxonomy of skills. [less ▲]

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See detailInductively coupled plasma-mass spectrometric (ICP-MS) analysis of silicate rocks and minerals
Vander Auwera, Jacqueline ULg; Bologne, Guy; Roelandts, Iwan et al

in Geologica Belgica (1998), 1

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See detailInduire des changements de comportements
Partoune, Christine ULg

in Tableau de bord "Participation et espaces publics" - Pour un développement et une gestion concertée des espaces publics (2010)

Plus précisément, le titre de cette fiche devrait être "Induire des changements communs de comportements dans les processus de participation des citoyennes et des citoyens au développement et à la gestion ... [more ▼]

Plus précisément, le titre de cette fiche devrait être "Induire des changements communs de comportements dans les processus de participation des citoyennes et des citoyens au développement et à la gestion des espaces publiques". Partant d’une réflexion sur le sens des mots et des concepts ici-présents, ce document devrait aider l’animateur territorial à définir et emprunter la posture la plus adéquate, au moment d’accompagner un groupe dans de tels processus de participation. [less ▲]

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See detailIndustrial Advertising Effects and Budgeting Practices
Choffray, Jean-Marie ULg; Lilien, Gary L.; Silk, Alvin J. et al

in Journal of Marketing (1976), 40(January), 16-24

This paper is concerned with the determination of expenditure levels for industrial advertising. Its purpose is to review available research and to examine practices currently used in budgeting industrial ... [more ▼]

This paper is concerned with the determination of expenditure levels for industrial advertising. Its purpose is to review available research and to examine practices currently used in budgeting industrial marketing activities. [less ▲]

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