45 results on '"Liénard F"'
Search Results
2. EPILEPSY ASSOCIATED WITH CEREBROTENDINOUS XANTHOMATOSIS SUCCESFULLY TREATED BY CHENODEOXYCHOLIC ACID: p280
- Author
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Vrielynck, P., Marchese, A., Roland, D., Liénard, F., Andries, S., Ghariani, S., and Van Rijckevorsel, K.
- Published
- 2012
3. CO-48: Les canaux TRPC3 de l'hypothalamus jouent un rôle fondamental dans la détection cérébrale du glucose et l'homéostasie énergétique
- Author
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Fioramonti, X., primary, Chrétien, C., additional, Fenech, C., additional, Liénard, F., additional, Grall, S., additional, Bergès, R., additional, Pénicaud, L., additional, and Leloup, C., additional
- Published
- 2016
- Full Text
- View/download PDF
4. Home language surveys as a starting point for language policy development in education in Suriname
- Author
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Yagmur, K., Kroon, S., Laroussi, F., Liénard, F., and Language and Globalization
- Published
- 2013
5. P185 Canaux TRPC3: nouveau mécanisme impliqué dans la sensibilité hypothalamique au glucose et le contrôle de l’homéostasie énergétique
- Author
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Fioramonti, X., primary, Chrétien, C., additional, Fenech, C., additional, Liénard, F., additional, Grall, S., additional, Pénicaud, L., additional, and Leloup, C., additional
- Published
- 2015
- Full Text
- View/download PDF
6. Epileptic syndromes: differential treatment in infants, children, and adolescents.
- Author
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Foulon, Martine, Aeby, Alec, Buzatu, Marga, Christiaens, Florence, de Borchgrave d'Alténa, Valérie, De Cocq, C, De Tourtchaninoff, Marianne, Dubru, J M, Ghariani, S, Grisar, T, Legros, Bernard, Liénard, F, Ossemann, M, Tugendhaft, Patrick, Van Bogaert, Patrick, van Rijckevorsel, Kenou, Verheulpen, Denis, Vrielynck, P, Working group of francophone reference centres for refractory epilepsy, Foulon, Martine, Aeby, Alec, Buzatu, Marga, Christiaens, Florence, de Borchgrave d'Alténa, Valérie, De Cocq, C, De Tourtchaninoff, Marianne, Dubru, J M, Ghariani, S, Grisar, T, Legros, Bernard, Liénard, F, Ossemann, M, Tugendhaft, Patrick, Van Bogaert, Patrick, van Rijckevorsel, Kenou, Verheulpen, Denis, Vrielynck, P, and Working group of francophone reference centres for refractory epilepsy
- Abstract
This paper proposes therapeutic guidelines for the management of some epileptic syndromes in infants, children, and adolescents, based on available medical literature and clinical practice in the French Community of Belgium. The guidelines address both epileptic encephalopathies (West syndrome, Lennox-Gastaut syndrome, and Dravet syndrome) and idiopathic epilepsies (typical absence seizures, epilepsy with centro-temporal spikes and juvenile myoclonic epilepsy)., Journal Article, Review, info:eu-repo/semantics/published
- Published
- 2011
7. Guidelines for the management of epilepsy in the elderly.
- Author
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Ossemann, M, Bruls, E, de Borchgrave d'Alténa, Valérie, De Cock, C, Delcourt, C, Delvaux, V, Depondt, Chantal, De Tourtchaninoff, Marianne, Grisar, T, Legros, Benjamin, Liénard, F, Lievens, I, Sadzot, B., van Rijckevorsel, Kenou, Groupe de travail des Centres francophones de référence de I'epilepsie réfractaire, Ossemann, M, Bruls, E, de Borchgrave d'Alténa, Valérie, De Cock, C, Delcourt, C, Delvaux, V, Depondt, Chantal, De Tourtchaninoff, Marianne, Grisar, T, Legros, Benjamin, Liénard, F, Lievens, I, Sadzot, B., van Rijckevorsel, Kenou, and Groupe de travail des Centres francophones de référence de I'epilepsie réfractaire
- Abstract
Seizures starting in patients over 60 years old are frequent. Diagnosis is sometimes difficult and frequently under- or overrated. Cerebrovascular disorders are the main cause of a first seizure. Because of more frequent comorbidities, physiologic changes, and a higher sensitivity to drugs, treatment has some specificity in elderly people. The aim of this paper is to present the result of a consensus meeting held in October 2004 by a Belgian French-speaking group of epileptologists and to propose guidelines for the management and the treatment of epilepsy in elderly people., Journal Article, Practice Guideline, info:eu-repo/semantics/published
- Published
- 2006
8. O20 Rôle de l’Acyl-CoA Binding Protein dans le contrôle hypothalamique de la balance énergétique
- Author
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Alquier, T., Bouyakdan, K., Budry, L., Taib, B., Chrétien, C., Rodaros, D., Lienard, F., Mandrup, S., Pénicaud, L., and Fioramonti, X.
- Published
- 2015
- Full Text
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9. Effects of DOCA pretreatment on neuronal sensitivity and cell responsiveness to angiotensin II, in the bed nucleus of the stria terminalis in the rat
- Author
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Liénard, F., primary, Thornton, S.N., additional, Martial, F.P., additional, Mousseau, M.-C., additional, Galaverna, O., additional, Meile, M.-J., additional, and Nicolaïdis, S., additional
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- 1996
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10. Blockade of central angiotensin II type 1 and type 2 receptors suppresses adrenalectomy-induced NaCl intake in rats
- Author
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Galaverna, O., primary, Polidori, C., additional, Sakai, R.R., additional, Liénard, F., additional, Chow, S.Y., additional, and Fluharty, S.J., additional
- Published
- 1996
- Full Text
- View/download PDF
11. Clinical and EEG findings in six patients with altered mental status receiving tiagabine therapy
- Author
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de Borchgrave, V., Lienard, F., Willemart, Th., and van Rijckevorsel, K.
- Published
- 2003
- Full Text
- View/download PDF
12. Mutagenicity studies on ethylenethiourea. I. Microbial assay
- Author
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Shirasu, Y., Moriya, M., Lienard, F., and Kato, K.
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- 1976
- Full Text
- View/download PDF
13. Diglossie et pratiques discursives numériques en Côte d’Ivoire : la question de l’écriture des langues ivoiriennes
- Author
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Blé, Stéphanie, N'Goran Poamé, Léa, Liénard, Fabien, Liénard, Fabien, Liénard F., Zlitni S., Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Fabien Liénard, Sami Zlitni, Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[SHS.LANGUE]Humanities and Social Sciences/Linguistics ,[SHS.LANGUE] Humanities and Social Sciences/Linguistics ,ComputingMilieux_MISCELLANEOUS ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences - Abstract
International audience
- Published
- 2018
14. Serious games, gaming, learning and crisis communication : insights from the literature
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Mykkänen, Markus, Vos, Marita, Liénard, F., and Zlitni, S.
- Subjects
serious gaming ,kriisiviestintä - Abstract
peerReviewed
- Published
- 2016
15. Traces contemporaines : corporéité, scripturalité, identité et territorialité
- Author
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Zlitni, Sami, Liénard, Fabien, Galinon-Mélénec, Béatrice, Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Equipe Homme-trace, Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Galinon-Mélénec B., Liénard F., Zlitni S., Liénard, Fabien, Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), and Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS)
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[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2015
16. Electronic communication in digital societies
- Author
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Zlitni, Sami, Liénard, Fabien, Haan, Marina, Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Zlitni S., Liénard F., Liénard, Fabien, Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2015
17. Significations, figures, formes et traces : penser les interactions à travers l’écriture d’une communauté d’alumni en ligne
- Author
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Alexander Frame, Gilles Brachotte, Centre Interlangues - Texte, Image, Langage ( TIL ), Université de Bourgogne ( UB ), Communications, Médiations, Organisations, Savoirs ( CIMEOS ), Béatrice Galinon Mélenec, Fabien Liénard, Sami Zlitni, uB-link, Maison des Sciences de l'Homme, MSH Dijon, Galinon-Mélénec, B., Liénard, F., Zlitni, S., Centre Interlangues - Texte, Image, Langage (TIL), Université de Bourgogne (UB), Communications, Médiations, Organisations, Savoirs [Dijon] (CIMEOS), Université de Bourgogne (UB)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université du Havre, and Communications, Médiations, Organisations, Savoirs (CIMEOS)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,Communication ,05 social sciences ,Twitter ,uB-link ,réseaux socionumériques ,interaction ,Semiopragmatique ,050801 communication & media studies ,ventriloquie ,Alumni ,Ecriture collaborative ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,[SHS]Humanities and Social Sciences ,0508 media and communications ,Figuration ,0502 economics and business ,[ SHS.INFO ] Humanities and Social Sciences/Library and information sciences ,Semiopragmatics ,[SHS] Humanities and Social Sciences ,050203 business & management ,ComputingMilieux_MISCELLANEOUS ,Trace - Abstract
National audience; Ce chapitre examine les interactions en ligne entre des membres d’une communauté d’alumni. Il considère que ces interactions, qui se manifestent sous l’unique forme de traces écrites, permettent aux membres d’un groupe de participer à la performance d’une culture et d’une identité collectives, mais aussi à tout un chacun de se démarquer sur le plan identitaire. Sur le plan théorique, le chapitre met en relation le modèle sémiopragmatique des interactions (Frame et Boutaud), l’approche ventriloque de François Cooren, inspiré de la théorie de l’Acteur-réseau (Latour), et le paradigme de l’Homme trace. Ce paradigme nous aide à mieux comprendre le rôle des objets à côté des acteurs humains dans les interactions, en recentrant le regard sur le rôle central des traces matérielles et immatérielles. Il permet ainsi de transcender les frontières entre communication médiaté par ordinateur et communication interpersonnelle.
- Published
- 2015
18. La révolution tunisienne ou l’émergence d’un nouvel espace discursif
- Author
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Zlitni, Sami, Liénard, Fabien, Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Zlitni S., Liénard F., Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS ,[SHS.SCIPO]Humanities and Social Sciences/Political science - Abstract
International audience
- Published
- 2013
19. Communiquer à l’ère des TIC dans la société de l’information
- Author
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Liénard, Fabien, Zlitni, Sami, Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Zlitni S., Liénard F., Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2013
20. Les campagnes des compagnes: : Mise en scène de la vie publique et privée
- Author
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Frame , Alexander, Brachotte , Gilles, Centre Interlangues - Texte, Image, Langage ( TIL ), Université de Bourgogne ( UB ), 3S, Communications, Médiations, Organisations, Savoirs ( CIMEOS ), Université de Bourgogne ( UB ) -Université de Bourgogne ( UB ), Zlitni, S. & Liénard, F., Centre Interlangues - Texte, Image, Langage (TIL), Université de Bourgogne (UB), Communications, Médiations, Organisations, Savoirs (CIMEOS), Université de Bourgogne (UB)-Université de Bourgogne (UB), Zlitni, S. & Liénard, and F.
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[ SHS.INFO ] Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2013
21. Electronic writing in Mayotte: a case study of texting
- Author
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Liénard, Fabien, Liénard, Fabien, Laroussi F., Liénard F., Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), and Normandie Université (NU)-Université de Caen Normandie (UNICAEN)
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[SHS] Humanities and Social Sciences ,ComputingMilieux_MISCELLANEOUS ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,[SHS]Humanities and Social Sciences - Abstract
International audience
- Published
- 2013
22. Les campagnes des compagnes
- Author
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Frame, Alexander, Brachotte, Gilles, Centre Interlangues - Texte, Image, Langage ( TIL ), Université de Bourgogne ( UB ), 3S, Communications, Médiations, Organisations, Savoirs ( CIMEOS ), Université de Bourgogne ( UB ) -Université de Bourgogne ( UB ), Zlitni, S. & Liénard, F., Frame, Alexander, Centre Interlangues - Texte, Image, Langage (TIL), Université de Bourgogne (UB), Communications, Médiations, Organisations, Savoirs (CIMEOS), Université de Bourgogne (UB)-Université de Bourgogne (UB), Zlitni, S. & Liénard, and F.
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[ SHS.INFO ] Humanities and Social Sciences/Library and information sciences ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2012
23. Les frontières pédagogiques sont-elles remises en question par l'utilisation des réseaux sociaux ?: L'implémentation d'objets d'apprentissage sociaux dans un espace de communication électronique médiée
- Author
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Panckhurst, Rachel, Marsh, Debra, Praxiling UMR 5267 (Praxiling), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre National de la Recherche Scientifique (CNRS), Private eLearning consultant, iconnect, Mauguio, France, Liénard, Fabien et Zlitni, Sami, Praxiling (Praxiling), iconnect (iconnect), Liénard F., Zlitni S., and Panckhurst, Rachel
- Subjects
apprentissage autonome ,[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,enseignement supérieur ,apprentissage collaborative ,[SHS.LANGUE] Humanities and Social Sciences/Linguistics ,communautés de pratiques ,objets d'apprentissage sociaux ,communication électronique ,réseaux sociaux ,formation ouverte et à distance ,eLearning ,réseaux pédagogiques ,[SHS.LANGUE]Humanities and Social Sciences/Linguistics ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience; Depuis mai 2007, nous menons des expérimentations pédagogiques dans un contexte d'enseignement supérieur professionnel en essayant d'évaluer les avantages et les défis lies à l'incorporation de réseaux sociaux pour des échanges pédagogiques au sein de cursus universitaires pré-établis. Un environnement d'apprentissage collaboratif et une communauté de pratiques (CoP) en ligne ont été créés, et les étudiants en M2 (poursuivant leurs études entièrement à distance) ont été invités à s'en servir afin de discuter et partager à propos de pratiques pédagogiques en formation ouverte et à distance, via un réseau d'échanges pédagogiques pour étudiants en eLearning (REeL) privé, mis en place grâce aux deux outils de réseaux sociaux : Ning et grou.ps . L'objectif de l'expérimentation pédagogique s'échelonnant sur trois ans était de placer les étudiants au centre du processus d'apprentissage et de leur permettre, d'une part, de faire une expérience pratique, et, d'autre part, de réfléchir à propos de l'apprentissage collaborative en ligne à travers des projets spécifiques. Cet article décrit l'étude de cas la plus récente (2009-2010) et s'interroge sur l'implémentation d'" objets d'apprentissage sociaux " (Weller, 2008) au sein d'environnements pédagogiques électroniquement médiés.
- Published
- 2011
24. Le SMS à Mayotte : le cas d’un écrit ordinaire quotidien favorisant la pratique des langues
- Author
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Liénard, Fabien, Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Laroussi F., Liénard F., Identité et Différenciation de l’Espace, de l’Environnement et des Sociétés (IDEES), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Normandie Université (NU)-Université de Caen Normandie (UNICAEN), and Liénard, Fabien
- Subjects
[SHS.INFO]Humanities and Social Sciences/Library and information sciences ,[SHS.LANGUE]Humanities and Social Sciences/Linguistics ,[SHS.LANGUE] Humanities and Social Sciences/Linguistics ,[SHS.INFO] Humanities and Social Sciences/Library and information sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2010
25. Hypothalamic Glucose Hypersensitivity-Induced Insulin Secretion in the Obese Zücker Rat Is Reversed by Central Ghrelin Treatment.
- Author
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Carneiro L, Fenech C, Liénard F, Grall S, Abed B, Haydar J, Allard C, Desmoulins L, Paccoud R, Brindisi MC, Mouillot T, Brondel L, Fioramonti X, Pénicaud L, Jacquin-Piques A, and Leloup C
- Subjects
- Animals, Rats, Male, Mitochondria metabolism, Mitochondria drug effects, Insulin metabolism, Insulin Resistance, Ghrelin metabolism, Hypothalamus metabolism, Obesity metabolism, Reactive Oxygen Species metabolism, Glucose metabolism, Insulin Secretion drug effects, Rats, Zucker
- Abstract
Aims: Part of hypothalamic (mediobasal hypothalamus [MBH]) neurons detect changes in blood glucose levels that in turn coordinate the vagal control of insulin secretion. This control cascade requires the production of mitochondrial reactive oxygen species (mROS), which is altered in models of obesity and insulin resistance. Obese, insulin-resistant Zücker rats are characterized by hypothalamic hypersensitivity to glucose. This initiates an abnormal vagus-induced insulin secretion, associated with an overproduction of mROS in response to a low glucose dose. Here, we hypothesized that ghrelin, known to buffer reactive oxygen species (ROS) via mitochondrial function, may be a major component of the hypothalamic glucose hypersensitivity in the hypoghrelinemic obese Zücker rat. Results: Hypothalamic glucose hypersensitivity-induced insulin secretion of Zücker obese rats was reversed by ghrelin pretreatment. The overproduction of MBH mROS in response to a low glucose load no longer occurred in obese rats that had previously received the cerebral ghrelin infusion. This decrease in mROS production was accompanied by a normalization of oxidative phosphorylation (OXPHOS). Conversely, blocking the action of ghrelin with a growth hormone secretagogue receptor antagonist in a model of hyperghrelinemia (fasted rats) completely restored hypothalamic glucose sensing-induced insulin secretion that was almost absent in this physiological situation. Accordingly, ROS signaling and mitochondrial activity were increased by the ghrelin receptor antagonist. Innovation: These results demonstrate for the first time that ghrelin addressed only to the brain could have a protective effect on the defective control of insulin secretion in the insulin-resistant, hypoghrelinemic obese subject. Conclusions: Ghrelin, through its action on OXPHOS, modulates mROS signaling in response to cerebral hyperglycemia and the consequent vagal control of insulin secretion. In insulin-resistant obese states, brain hypoghrelinemia could be responsible for the nervous defect in insulin secretion.
- Published
- 2024
- Full Text
- View/download PDF
26. Microgliosis: a double-edged sword in the control of food intake.
- Author
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Salvi J, Andreoletti P, Audinat E, Balland E, Ben Fradj S, Cherkaoui-Malki M, Heurtaux T, Liénard F, Nédélec E, Rovère C, Savary S, Véjux A, Trompier D, and Benani A
- Subjects
- Homeostasis, Brain metabolism, Eating, Energy Metabolism physiology, Hypothalamus metabolism, Adipose Tissue metabolism
- Abstract
Maintaining energy balance is essential for survival and health. This physiological function is controlled by the brain, which adapts food intake to energy needs. Indeed, the brain constantly receives a multitude of biological signals that are derived from digested foods or that originate from the gastrointestinal tract, energy stores (liver and adipose tissues) and other metabolically active organs (muscles). These signals, which include circulating nutrients, hormones and neuronal inputs from the periphery, collectively provide information on the overall energy status of the body. In the brain, several neuronal populations can specifically detect these signals. Nutrient-sensing neurons are found in discrete brain areas and are highly enriched in the hypothalamus. In turn, specialized brain circuits coordinate homeostatic responses acting mainly on appetite, peripheral metabolism, activity and arousal. Accumulating evidence shows that hypothalamic microglial cells located at the vicinity of these circuits can influence the brain control of energy balance. However, microglial cells could have opposite effects on energy balance, that is homeostatic or detrimental, and the conditions for this shift are not totally understood yet. One hypothesis relies on the extent of microglial activation, and nutritional lipids can considerably change it., (© 2022 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)
- Published
- 2024
- Full Text
- View/download PDF
27. Experimental study of a nanoscale translocation ratchet.
- Author
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Molcrette B, Chazot-Franguiadakis L, Liénard F, Balassy Z, Freton C, Grangeasse C, and Montel F
- Subjects
- Biological Transport, Fimbriae, Bacterial metabolism, Kinetics, DNA metabolism, Nanopores
- Abstract
Despite an extensive theoretical and numerical background, the translocation ratchet mechanism, which is fundamental for the transmembrane transport of biomolecules, has never been experimentally reproduced at the nanoscale. Only the Sec61 and bacterial type IV pilus pores were experimentally shown to exhibit a translocation ratchet mechanism. Here we designed a synthetic translocation ratchet and quantified its efficiency as a nanopump. We measured the translocation frequency of DNA molecules through nanoporous membranes and showed that polycations at the trans side accelerated the translocation in a ratchet-like fashion. We investigated the ratchet efficiency according to geometrical and kinetic parameters and observed the ratchet to be only dependent on the size of the DNA molecule with a power law [Formula: see text]. A threshold length of 3 kbp was observed, below which the ratchet did not operate. We interpreted this threshold in a DNA looping model, which quantitatively explained our results.
- Published
- 2022
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- View/download PDF
28. A multiscale time-Laplace method to extract relaxation times from non-stationary dynamic light scattering signals.
- Author
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Liénard F, Freyssingeas É, and Borgnat P
- Subjects
- Dynamic Light Scattering, Light
- Abstract
Dynamic Light Scattering (DLS) is a well-known technique to study the relaxation times of systems at equilibrium. In many soft matter systems, we actually have to consider non-equilibrium or non-stationary situations. We discuss here the principles, the signal processing techniques we developed, based on regularized inverse Laplace transform, sliding with time, and the light scattering signal acquisition, which enable us to use DLS experiments in this general situation. In this article, we show how to obtain such a time-Laplace analysis. We claim that this method can be adapted to numerous DLS experiments dealing with non-equilibrium systems so as to extract the non-stationary distribution of relaxation times. To prove that, we test this time-Laplace method on three different non-equilibrium processes or systems investigated by means of the DLS technique: the cooling kinetics of a colloidal particle solution, the sol-gel transition and the internal dynamics of a living cell nucleus.
- Published
- 2022
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29. Monitoring of a mound made of sediments: exploring landscaping as a way to upgrade dredged materials (VALSE project).
- Author
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Liénard F and Haouche L
- Subjects
- Belgium, Environmental Monitoring, France, Plants, Geologic Sediments, Soil
- Abstract
Because of the shallow relief in Belgium and northern France, the dredging of waterways generates significant quantities of sediments for which few valorization pathways are validated. Waterways operators and public authorities are still waiting for efficient valorization solutions. The VALSE project, funded by the Interreg V FWVl program, aims to validate valorization pathways through large-scale works that promote a good integration in territories and a sustainable use. In this context, landscaping could be an upgrading solution; hence, a mound made with unpolluted sediments is ecologically and ecotoxicologically monitored over time to assess if dredged materials are harmful for the environment. An embankment near the studied site was chosen as a reference. The monitoring consists of, on the one hand, in situ flora and substrate macro-invertebrates surveys. On the other hand, ecotoxicity tests are performed on sediments and soil respectively taken from the mound and the embankment: the activity of nitrifying bacteria in these substrates and the reproduction of an earthworm (Eisenia fetida) are studied. First, results show that the sediments do not seem to impact negatively plant colonization or the settlement of substrate macro-invertebrates. About laboratory testing, sediments do not seem to interfere with natural nitrification process and E. fetida reproduction seems equivalent in sediments and embankment soil. These results do not allow drawing any definite conclusion because they relate to a first year of experimentation only, but they tend towards a good integration of the mound in the surrounding environment for the monitored parameters.
- Published
- 2020
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30. Postprandial Hyperglycemia Stimulates Neuroglial Plasticity in Hypothalamic POMC Neurons after a Balanced Meal.
- Author
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Nuzzaci D, Cansell C, Liénard F, Nédélec E, Ben Fradj S, Castel J, Foppen E, Denis R, Grouselle D, Laderrière A, Lemoine A, Mathou A, Tolle V, Heurtaux T, Fioramonti X, Audinat E, Pénicaud L, Nahon JL, Rovère C, and Benani A
- Subjects
- Animals, Blood Glucose metabolism, Electrophysiological Phenomena, Feeding Behavior, Hyperglycemia blood, Mice, Inbred C57BL, Mice, Transgenic, Postprandial Period, Synapses metabolism, Hyperglycemia physiopathology, Hypothalamus metabolism, Meals, Neuroglia pathology, Neuronal Plasticity, Neurons metabolism, Pro-Opiomelanocortin metabolism
- Abstract
Mechanistic studies in rodents evidenced synaptic remodeling in neuronal circuits that control food intake. However, the physiological relevance of this process is not well defined. Here, we show that the firing activity of anorexigenic POMC neurons located in the hypothalamus is increased after a standard meal. Postprandial hyperactivity of POMC neurons relies on synaptic plasticity that engages pre-synaptic mechanisms, which does not involve structural remodeling of synapses but retraction of glial coverage. These functional and morphological neuroglial changes are triggered by postprandial hyperglycemia. Chemogenetically induced glial retraction on POMC neurons is sufficient to increase POMC activity and modify meal patterns. These findings indicate that synaptic plasticity within the melanocortin system happens at the timescale of meals and likely contributes to short-term control of food intake. Interestingly, these effects are lost with a high-fat meal, suggesting that neuroglial plasticity of POMC neurons is involved in the satietogenic properties of foods., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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31. Proof of concept: Effect of GLP-1 agonist on food hedonic responses and taste sensitivity in poor controlled type 2 diabetic patients.
- Author
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Brindisi MC, Brondel L, Meillon S, Barthet S, Grall S, Fenech C, Liénard F, Schlich P, Astruc K, Mouillot T, Jacquin-Piques A, Leloup C, Vergès B, and Pénicaud L
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Biomarkers analysis, Choice Behavior, Diabetes Mellitus, Type 2 psychology, Female, Follow-Up Studies, Humans, Hunger physiology, Hypoglycemic Agents therapeutic use, Male, Middle Aged, Obesity prevention & control, Prognosis, Taste physiology, Young Adult, Diabetes Mellitus, Type 2 drug therapy, Eating psychology, Feeding Behavior psychology, Food Preferences psychology, Glucagon-Like Peptide 1 agonists, Liraglutide therapeutic use, Mental Recall
- Abstract
Aims: GLP-1 analogues decrease food intake and have great promise for the fight against obesity. Little is known about their effects on food hedonic sensations and taste perception in poor controlled patients with type 2 diabetes (T2D)., Materials and Methods: Eighteen T2D patients with BMI ≥25 kg/m
2 and poor controlled glycemia were studied before and after 3 months of treatment with Liraglutide. Detection thresholds for salty, sweet and bitter tastes, optimal preferences, olfactory liking, wanting and recalled liking for several food items were assessed. Subjects also answered questionnaires to measure their attitudes to food., Results: T2D patients had a significant decrease in bodyweight and HbA1c after treatment with Liraglutide. Liraglutide improved gustative detection threshold of sweet flavors, and decreased wanting for sweet foods and recalled liking for fatty foods. It also led to a decrease in feelings of hunger., Conclusions: Liraglutide increases sensitivity to sweet tastes and decreases pleasure responses for fatty foods in poor controlled T2D patients, and is of particular interest in the understanding of the mechanisms of weight loss., Clinical Trial: NCT02674893., (Copyright © 2019 Diabetes India. Published by Elsevier Ltd. All rights reserved.)- Published
- 2019
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32. The gliotransmitter ACBP controls feeding and energy homeostasis via the melanocortin system.
- Author
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Bouyakdan K, Martin H, Liénard F, Budry L, Taib B, Rodaros D, Chrétien C, Biron É, Husson Z, Cota D, Pénicaud L, Fulton S, Fioramonti X, and Alquier T
- Subjects
- Animals, Astrocytes pathology, Cell Line, Diazepam Binding Inhibitor genetics, Female, Hyperphagia genetics, Hyperphagia pathology, Male, Mice, Mice, Knockout, Neurons metabolism, Neurons pathology, Obesity genetics, Obesity pathology, Pro-Opiomelanocortin genetics, Astrocytes metabolism, Diazepam Binding Inhibitor metabolism, Eating, Energy Metabolism, Hyperphagia metabolism, Obesity metabolism, Pro-Opiomelanocortin metabolism
- Abstract
Glial cells have emerged as key players in the central control of energy balance and etiology of obesity. Astrocytes play a central role in neural communication via the release of gliotransmitters. Acyl-CoA binding protein (ACBP)-derived endozepines are secreted peptides that modulate the GABAA receptor. In the hypothalamus, ACBP is enriched in arcuate nucleus (ARC) astrocytes, ependymocytes and tanycytes. Central administration of the endozepine octadecaneuropeptide (ODN) reduces feeding and improves glucose tolerance, yet the contribution of endogenous ACBP in energy homeostasis is unknown. We demonstrated that ACBP deletion in GFAP+ astrocytes, but not in Nkx2.1-lineage neural cells, promoted diet-induced hyperphagia and obesity in both male and female mice, an effect prevented by viral rescue of ACBP in ARC astrocytes. ACBP-astrocytes were observed in apposition with proopiomelanocortin (POMC) neurons and ODN selectively activated POMC neurons through the ODN-GPCR but not GABAA, and supressed feeding while increasing carbohydrate utilization via the melanocortin system. Similarly, ACBP overexpression in ARC astrocytes reduced feeding and weight gain. Finally, the ODN-GPCR agonist decreased feeding and promoted weight loss in ob/ob mice. These findings uncover ACBP as an ARC gliopeptide playing a key role in energy balance control and exerting strong anorectic effects via the central melanocortin system.
- Published
- 2019
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33. Mitochondrial Dynamin-Related Protein 1 (DRP1) translocation in response to cerebral glucose is impaired in a rat model of early alteration in hypothalamic glucose sensing.
- Author
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Desmoulins L, Chrétien C, Paccoud R, Collins S, Cruciani-Guglielmacci C, Galinier A, Liénard F, Quinault A, Grall S, Allard C, Fenech C, Carneiro L, Mouillot T, Fournel A, Knauf C, Magnan C, Fioramonti X, Pénicaud L, and Leloup C
- Subjects
- AMP-Activated Protein Kinase Kinases, Animals, Carotid Arteries metabolism, Insulin Secretion, Insulin-Secreting Cells metabolism, Male, Protein Kinases metabolism, Protein Transport, Rats, Rats, Wistar, Reactive Oxygen Species metabolism, Signal Transduction, Blood Glucose metabolism, Dynamins metabolism, Hypothalamus metabolism, Mitochondria metabolism, Sensory Receptor Cells metabolism
- Abstract
Objective: Hypothalamic glucose sensing (HGS) initiates insulin secretion (IS) via a vagal control, participating in energy homeostasis. This requires mitochondrial reactive oxygen species (mROS) signaling, dependent on mitochondrial fission, as shown by invalidation of the hypothalamic DRP1 protein. Here, our objectives were to determine whether a model with a HGS defect induced by a short, high fat-high sucrose (HFHS) diet in rats affected the fission machinery and mROS signaling within the mediobasal hypothalamus (MBH)., Methods: Rats fed a HFHS diet for 3 weeks were compared with animals fed a normal chow. Both in vitro (calcium imaging) and in vivo (vagal nerve activity recordings) experiments to measure the electrical activity of isolated MBH gluco-sensitive neurons in response to increased glucose level were performed. In parallel, insulin secretion to a direct glucose stimulus in isolated islets vs. insulin secretion resulting from brain glucose stimulation was evaluated. Intra-carotid glucose load-induced hypothalamic DRP1 translocation to mitochondria and mROS (H
2 O2 ) production were assessed in both groups. Finally, compound C was intracerebroventricularly injected to block the proposed AMPK-inhibited DRP1 translocation in the MBH to reverse the phenotype of HFHS fed animals., Results: Rats fed a HFHS diet displayed a decreased HGS-induced IS. Responses of MBH neurons to glucose exhibited an alteration of their electrical activity, whereas glucose-induced insulin secretion in isolated islets was not affected. These MBH defects correlated with a decreased ROS signaling and glucose-induced translocation of the fission protein DRP1, as the vagal activity was altered. AMPK-induced inhibition of DRP1 translocation increased in this model, but its reversal through the injection of the compound C, an AMPK inhibitor, failed to restore HGS-induced IS., Conclusions: A hypothalamic alteration of DRP1-induced fission and mROS signaling in response to glucose was observed in HGS-induced IS of rats exposed to a 3 week HFHS diet. Early hypothalamic modifications of the neuronal activity could participate in a primary defect of the control of IS and ultimately, the development of diabetes., (Copyright © 2018 The Authors. Published by Elsevier GmbH.. All rights reserved.)- Published
- 2019
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34. Lack of Hypothalamus Polysialylation Inducibility Correlates With Maladaptive Eating Behaviors and Predisposition to Obesity.
- Author
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Brenachot X, Nédélec E, Ben Fradj S, Boudry G, Douard V, Laderrière A, Lemoine A, Liénard F, Nuzzaci D, Pénicaud L, Rigault C, and Benani A
- Abstract
High variability exists in individual susceptibility to develop overweight in an obesogenic environment and the biological underpinnings of this heterogeneity are poorly understood. In this brief report, we show in mice that the vulnerability to diet-induced obesity is associated with low level of polysialic acid-neural cell adhesion molecule (PSA-NCAM), a factor of neural plasticity, in the hypothalamus. As we previously shown that reduction of hypothalamic PSA-NCAM is sufficient to alter energy homeostasis and promote fat storage under hypercaloric pressure, inter-individual variability in hypothalamic PSA-NCAM might account for the vulnerability to diet-induced obesity. These data support the concept that reduced plasticity in brain circuits that control appetite, metabolism and body weight confers risk for eating disorders and obesity.
- Published
- 2018
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35. Transient Receptor Potential Canonical 3 (TRPC3) Channels Are Required for Hypothalamic Glucose Detection and Energy Homeostasis.
- Author
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Chrétien C, Fenech C, Liénard F, Grall S, Chevalier C, Chaudy S, Brenachot X, Berges R, Louche K, Stark R, Nédélec E, Laderrière A, Andrews ZB, Benani A, Flockerzi V, Gascuel J, Hartmann J, Moro C, Birnbaumer L, Leloup C, Pénicaud L, and Fioramonti X
- Subjects
- Animals, Blotting, Western, Fasting, Glucose Tolerance Test, Homeostasis, Hypothalamus cytology, Insulin Secretion, Male, Mice, Mice, Inbred C57BL, Rats, Rats, Sprague-Dawley, Real-Time Polymerase Chain Reaction, TRPC Cation Channels metabolism, Body Weight genetics, Eating genetics, Energy Metabolism genetics, Glucose metabolism, Hypothalamus metabolism, Insulin metabolism, Neurons metabolism, TRPC Cation Channels genetics
- Abstract
The mediobasal hypothalamus (MBH) contains neurons capable of directly detecting metabolic signals such as glucose to control energy homeostasis. Among them, glucose-excited (GE) neurons increase their electrical activity when glucose rises. In view of previous work, we hypothesized that transient receptor potential canonical type 3 (TRPC3) channels are involved in hypothalamic glucose detection and the control of energy homeostasis. To investigate the role of TRPC3, we used constitutive and conditional TRPC3-deficient mouse models. Hypothalamic glucose detection was studied in vivo by measuring food intake and insulin secretion in response to increased brain glucose level. The role of TRPC3 in GE neuron response to glucose was studied by using in vitro calcium imaging on freshly dissociated MBH neurons. We found that whole-body and MBH TRPC3-deficient mice have increased body weight and food intake. The anorectic effect of intracerebroventricular glucose and the insulin secretory response to intracarotid glucose injection are blunted in TRPC3-deficient mice. TRPC3 loss of function or pharmacological inhibition blunts calcium responses to glucose in MBH neurons in vitro. Together, the results demonstrate that TRPC3 channels are required for the response to glucose of MBH GE neurons and the central effect of glucose on insulin secretion and food intake., (© 2017 by the American Diabetes Association.)
- Published
- 2017
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36. Gut Commensal E. coli Proteins Activate Host Satiety Pathways following Nutrient-Induced Bacterial Growth.
- Author
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Breton J, Tennoune N, Lucas N, Francois M, Legrand R, Jacquemot J, Goichon A, Guérin C, Peltier J, Pestel-Caron M, Chan P, Vaudry D, do Rego JC, Liénard F, Pénicaud L, Fioramonti X, Ebenezer IS, Hökfelt T, Déchelotte P, and Fetissov SO
- Subjects
- Adenosine Triphosphate biosynthesis, Amygdala metabolism, Animals, Electrophysiological Phenomena, Endopeptidase Clp, Escherichia coli metabolism, Feeding Behavior, Female, Glucagon-Like Peptide 1 metabolism, Heat-Shock Proteins metabolism, Hypothalamus metabolism, Male, Mice, Mice, Inbred C57BL, Neurons metabolism, Peptide YY metabolism, Pro-Opiomelanocortin metabolism, Proteomics, Proto-Oncogene Proteins c-fos metabolism, Rats, Sprague-Dawley, Rats, Wistar, Escherichia coli growth & development, Escherichia coli Proteins metabolism, Gastrointestinal Tract microbiology, Satiety Response
- Abstract
The composition of gut microbiota has been associated with host metabolic phenotypes, but it is not known if gut bacteria may influence host appetite. Here we show that regular nutrient provision stabilizes exponential growth of E. coli, with the stationary phase occurring 20 min after nutrient supply accompanied by bacterial proteome changes, suggesting involvement of bacterial proteins in host satiety. Indeed, intestinal infusions of E. coli stationary phase proteins increased plasma PYY and their intraperitoneal injections suppressed acutely food intake and activated c-Fos in hypothalamic POMC neurons, while their repeated administrations reduced meal size. ClpB, a bacterial protein mimetic of α-MSH, was upregulated in the E. coli stationary phase, was detected in plasma proportional to ClpB DNA in feces, and stimulated firing rate of hypothalamic POMC neurons. Thus, these data show that bacterial proteins produced after nutrient-induced E. coli growth may signal meal termination. Furthermore, continuous exposure to E. coli proteins may influence long-term meal pattern., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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37. Role of the basolateral amygdala in retrieval of conditioned flavors in the awake rat.
- Author
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Liénard F, Desmoulins L, Pénicaud L, and Datiche F
- Subjects
- Action Potentials, Animals, Eating, Electrodes, Implanted, Food Deprivation, Glucose administration & dosage, Immunohistochemistry, Male, Oncogene Proteins v-fos metabolism, Rats, Wistar, Signal Processing, Computer-Assisted, Basolateral Nuclear Complex physiology, Conditioning, Psychological physiology, Food Preferences physiology, Neurons physiology, Taste Perception physiology
- Abstract
Learned association between odor, taste and further post-ingestive consequence is known as flavor nutrient conditioned preference. Amygdala is supposed to be one of the areas involved in these associations. In the present study, one flavor was associated with a 16% glucose (CS(+)) whereas another flavor was paired with less reinforcing 4% glucose (CS(-)). We showed that CS(+) presentation after conditioning increased Fos expression in the basolateral nucleus of amygdala (BLA). Furthermore, we performed electrophysiological recordings in the BLA in free moving rats. After preference acquisition, rats were exposed to either the CS(+) or the CS(-). The proportion of neurons showing a decreased activity during the CS(-) presentation was significantly higher in conditioned rats compared to controls. Among this neuronal population recorded in conditioned rats, we noticed a significant proportion of neurons that also showed a decreased activity during the CS(+) presentation. Our data indicate an involvement of BLA during retrieval of learned flavors. It also suggests that both flavors might have acquired a biological value through conditioning., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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38. Olfactory discrimination ability and brain expression of c-fos, Gir and Glut1 mRNA are altered in n-3 fatty acid-depleted rats.
- Author
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Hichami A, Datiche F, Ullah S, Liénard F, Chardigny JM, Cattarelli M, and Khan NA
- Subjects
- Analysis of Variance, Animals, Behavior, Animal physiology, Body Weight physiology, Diet, Fat-Restricted methods, Discrimination Learning physiology, Gene Expression Regulation physiology, Glucose Transporter Type 1 metabolism, Male, Proto-Oncogene Proteins c-fos metabolism, RNA, Messenger metabolism, Rats, Rats, Wistar, Receptors, G-Protein-Coupled metabolism, Reverse Transcriptase Polymerase Chain Reaction methods, Time Factors, Brain metabolism, Discrimination, Psychological physiology, Fatty Acids, Omega-3 metabolism, Glucose Transporter Type 1 genetics, Proto-Oncogene Proteins c-fos genetics, Receptors, G-Protein-Coupled genetics, Smell physiology
- Abstract
The long-chain polyunsaturated n-3 fatty acids (n-3 PUFA), particularly docosahexaenoic acid (DHA), are abundantly present in the central nervous system and play an important role in cognitive functions such as learning and memory. We, therefore, investigated the effects of n-3 PUFA-depletion in rats (F2 generation) on the learning of an olfactory discrimination task, progressively acquired within a four-arm maze, and on the mRNA expression of some candidate genes, i.e., c-fos, Gir and glucose transporter (Glut1), which could reflect the level of cerebral activity. We observed that DHA contents were dramatically decreased in the olfactory bulb, the piriform cortex and the neocortex of n-3-depleted rats. Furthermore, the n-3 deficiency resulted in a mild olfactory learning impairment as these rats required more days to master the olfactory task compared to control rats. Real-time RT-PCR experiments revealed that the training induced the expression of c-fos mRNA in all the three regions of the brain whereas Gir and Glut1 mRNA were induced only in olfactory bulb and neocortex. However, such an increase was less marked in the n-3-deficient rats. Taken together, these results allow us to assume that the behavioural impairment in n-3-deficient rats is linked to the depletion of n-3 fatty acids in brain regions processing olfactory cues. Data are discussed in view of the possible role of some of these genes in learning-induced neuronal olfactory plasticity.
- Published
- 2007
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39. Guidelines for the management of epilepsy in the elderly.
- Author
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Ossemann M, Bruls E, de Borchgrave V, De Cock C, Delcourt C, Delvaux V, Depondt C, de Tourchaninoff M, Grisar T, Legros B, Liénard F, Lievens I, Sadzot B, and van Rijckevorsel K
- Subjects
- Aged, Algorithms, Brain drug effects, Brain physiopathology, Humans, Anticonvulsants therapeutic use, Epilepsy diagnosis, Epilepsy drug therapy
- Abstract
Seizures starting in patients over 60 years old are frequent. Diagnosis is sometimes difficult and frequently under- or overrated. Cerebrovascular disorders are the main cause of a first seizure. Because of more frequent comorbidities, physiologic changes, and a higher sensitivity to drugs, treatment has some specificity in elderly people. The aim of this paper is to present the result of a consensus meeting held in October 2004 by a Belgian French-speaking group of epileptologists and to propose guidelines for the management and the treatment of epilepsy in elderly people.
- Published
- 2006
40. Fos protein expression in olfactory-related brain areas after learning and after reactivation of a slowly acquired olfactory discrimination task in the rat.
- Author
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Roullet F, Liénard F, Datiche F, and Cattarelli M
- Subjects
- Animals, Functional Laterality physiology, Habenula physiology, Immunohistochemistry, Limbic System physiology, Psychomotor Performance physiology, Rats, Rats, Wistar, Discrimination Learning physiology, Discrimination, Psychological physiology, Learning physiology, Olfactory Pathways metabolism, Oncogene Proteins v-fos biosynthesis, Smell physiology
- Abstract
Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of pseudotrained rats were used: PO rats were not water restricted and were submitted to the olfactory stimuli in the maze without any reinforcement, whereas PW rats were water-deprived and systematically received water in the maze without any odorous stimulation. When the discrimination task was well mastered, a significantly lower Fos immunoreactivity was observed in T rats compared to PW and PO rats in most of the analyzed brain areas, which could reflect the post-acquisition consolidation process. Following memory reactivation, differences in Fos immunoreactivity between trained and some pseudotrained rats were found in the anterior part of piriform cortex, CA3, and orbitofrontal cortex. We also observed that Fos labeling was significantly higher in trained rats after memory reactivation than after acquisition of the olfactory task in most of the brain areas examined. Our results support the assumption of a differential involvement of neuronal networks after either learning or reactivation of an olfactory discrimination task.
- Published
- 2005
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41. Learning-stage dependent Fos expression in the rat brain during acquisition of an olfactory discrimination task.
- Author
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Roullet F, Datiche F, Liénard F, and Cattarelli M
- Subjects
- Analysis of Variance, Animals, Hippocampus metabolism, Immunochemistry, Limbic System metabolism, Male, Memory physiology, Parahippocampal Gyrus metabolism, Rats, Rats, Wistar, Smell physiology, Brain Mapping, Cerebral Cortex metabolism, Discrimination Learning physiology, Nerve Net metabolism, Oncogene Proteins v-fos metabolism
- Abstract
By using Fos immunocytochemistry, we investigated the activation in olfactory-related areas at three stages (the first and fourth days of conditioning and complete acquisition) of an olfactory discrimination learning task. The trained rats (T) had to associate one odour of a pair with water-reward within a four-arm maze whereas pseudo-trained (P) rats were only submitted to the olfactory cues without any reinforcement. In the piriform cortex, both T and P rats exhibited a higher immunoreactivity on the first day, which seemed to indicate a novelty-related Fos expression in this area, but whatever the learning-stage, no significant difference in Fos expression between T and P rats was observed. In hippocampus, Fos expression was significantly different between T and P rats in CA1 and CA3 on the first and fourth days respectively. Thus we showed a differential activation of CA1 and CA3 subfields which might support a possible functional heterogeneity. In the orbitofrontal cortex, Fos immunoreactivity was significantly higher in T rats compared to P rats when mastery of the discrimination task was complete. In contrast, no learning-related Fos expression was found in infralimbic and prelimbic cortices. The present data suggest an early implication of the hippocampal formation and a later involvement of neocortical areas throughout different stages of a progressively acquired olfactory learning task.
- Published
- 2005
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42. Cue valence representation studied by Fos immunocytochemistry after acquisition of a discrimination learning task.
- Author
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Roullet F, Datiche F, Liénard F, and Cattarelli M
- Subjects
- Animals, Behavior, Animal physiology, Cell Count, Cerebral Cortex metabolism, Gene Expression Regulation physiology, Hippocampus metabolism, Immunohistochemistry methods, Male, Maze Learning physiology, Neurons metabolism, Olfactory Pathways cytology, Rats, Rats, Wistar, Smell physiology, Conditioning, Operant physiology, Cues, Discrimination Learning physiology, Olfactory Pathways metabolism, Proto-Oncogene Proteins c-fos metabolism
- Abstract
The piriform cortex (PCx) and related structures such as hippocampus and frontal cortex could play an important role in olfactory memory. We investigated their involvement in learning the biological value of an odor cue, i.e. predicting reward or non-reward in a two-odor discrimination task. Rats were sacrificed after stimulation by either rewarded or non-rewarded odor and Fos immunocytochemistry was performed. The different experimental groups of rats did not show strongly differentiated Fos expression pattern in either the PCx or the hippocampus. A few differences were noted in frontal areas. In the ventro-lateral orbital cortex, rats, ramdomly rewarded during the conditionning had a higher Fos level in comparison with other groups. In infralimbic cortex, rats, which learned the reward value of the olfactory cue and were water-reinforced the day of sacrifice, showed a higher Fos expression. Data are discussed in view of the olfactory learning paradigm and of the accuracy of the control groups used in the present experimental design. The behavioural conditions leading to Fos expression are further discussed since Fos is a marker of learning-induced plasticity as well as a general activity marker which can be activated by a wide range of stimuli not directly linked to memory.
- Published
- 2004
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43. Acute sodium depletion modifies septo-preoptic neuron sensitivities to neurohormones.
- Author
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Liénard F, Galaverna O, Thornton SN, Meile MJ, and Nicolaïdis S
- Subjects
- Angiotensins, Animals, Imidazoles pharmacology, Losartan pharmacology, Male, Neurons metabolism, Preoptic Area cytology, Preoptic Area metabolism, Pyridines pharmacology, Rats, Rats, Wistar, Septum Pellucidum cytology, Septum Pellucidum metabolism, Aldosterone pharmacology, Angiotensin II pharmacology, Neurons drug effects, Preoptic Area drug effects, Septum Pellucidum drug effects, Sodium metabolism
- Abstract
Sodium (Na+) depletion induces sodium appetite to replenish Na+ loss. It appears to be a consequence of enhanced levels of aldosterone (Aldo) and angiotensin II (AII) in the plasma as well as in the brain. Mineralocorticoid pretreatment modifies the sensitivity of septo-preoptic neurons to locally applied AII and Aldo. Therefore, we investigated septo-preoptic neuronal sensitivities to AII and Aldo, as well as to the specific AII type-1 receptor (AT-1) non-peptide antagonist losartan (Los) and to the specific AII type-2 receptor (AT-2) non-peptide antagonist PD123319 after one Na+ depletion without repletion. We found that one Na+ depletion induced increases in the proportion of neurons inhibited by iontophoretic application of AII (20.5% vs. 7.8%, p=0.004) whereas, the proportion of neurons excited by Aldo was increased, (23.7% vs. 5%, p=0.001). Moreover, the proportion of neurons changing sensitivity to AII after one application of Aldo was increased in the furosemide group (44.2% vs. 20.4%, p=0.0123). The proportion of neurons inhibited by application of losartan was enhanced, (26.4% vs. 9.3%, p=0.03). No significant changes were found in response to PD123319 by itself. Moreover, there were more neurons which co-localized responses to both Los and PD123319 in the furosemide group than in the control group (29.7% vs. 8.6%, p=0.027). It is known that multidepletions induce an increased need-free sodium appetite and our present findings could well form part of the neuronal basis of this behavior., (Copyright 1998 Elsevier Science B.V.)
- Published
- 1998
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44. Angiotensin II receptor subtype antagonists can both stimulate and inhibit salt appetite in rats.
- Author
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Liénard F, Thornton SN, Martial FP, Mousseau MC, and Nicolaïdis S
- Subjects
- Angiotensin II administration & dosage, Animals, Appetite Regulation drug effects, Drinking Behavior drug effects, Injections, Intraventricular, Losartan, Male, Rats, Rats, Wistar, Saline Solution, Hypertonic, Time Factors, Angiotensin II pharmacology, Angiotensin Receptor Antagonists, Appetite Regulation physiology, Biphenyl Compounds pharmacology, Desoxycorticosterone pharmacology, Drinking Behavior physiology, Imidazoles pharmacology, Sodium Chloride administration & dosage, Tetrazoles pharmacology
- Abstract
In urethane-anaesthetised male Wistar rats iontophoretic application of the angiotensin II (Ang II) type 1 (AT-1) receptor specific nonpeptide antagonist losartan in the septo-preoptic continuum can produce neuronal excitation of short- and long-term duration which has been interpreted as removal of tonic Ang II-induced inhibition. Mineralocorticoid pretreatment, which increases neuronal sensitivity to Ang II to enhance salt appetite, also removes this losartan-induced long-term excitation. These results suggested steroid modulation of the AT-1 receptor and a complex involvement of Ang II in salt appetite. To investigate the role of the inhibitory action of central Ang II on salt appetite, we gave intracerebroventicular injections of a single, low dose (10 ng) of losartan in normal euhydrated rats and this produced, paradoxically, a progressive increase in salt intake (1.6 +/- 0.3 ml/day to 3.5 +/- 0.9 ml/day, n = 15, P < 0.05). Treatment of these salt enhanced rats with DOCA (0.5 mg/day, s.c., for 3 days) further increased the salt appetite, but then a second i.c.v. injection of the same dose of losartan significantly inhibited the enhanced salt appetite (4.7 +/- 0.7 to 1.3 +/- 0.4, n = 9, P < 0.05). These results provide evidence for a complex action of Ang II on the At-1 receptor mediating the generation of salt appetite that appears to involve either at least two functional subtypes of this AT-1 receptor, as already suggested by previous electrophysiological experiments, or one AT-1 receptor with several activation states.
- Published
- 1996
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45. Water versus salty taste and Iontophoretic ANGII responses of septopreoptic neurons in dehydrated and euhydrated awake rats.
- Author
-
Mousseau MC, Thornton SN, Liénard F, Martial FP, and Nicolaïdis S
- Subjects
- Animals, Iontophoresis, Male, Rats, Rats, Wistar, Angiotensin II pharmacology, Drinking physiology, Preoptic Area physiology, Salts pharmacology, Taste physiology
- Abstract
Little is known of the influence of gustatory, particularly salt, input on neurons of the forebrain and if the same neurons are sensitive to hydromineral balance humoral stimuli. In awake, nonpremedicated rats we recorded the activity of spontaneously active neurons in the preoptic/anterior hypothalamic area of dehydrated and euhydrated rats while allowing them to ingest water or a hypertonic salt solution (1.6% NaCl) administered to the tongue. The hormones angiotensin and aldosterone, both implicated in hydromineral balance, were applied by iontophoresis to the same neurons. In the dehydrated rats, 27% (15/55) of the spontaneously active neurons responded to a liquid (either water or the NaCl) applied to the tongue; in the euhydrated rats 23% (18/78) responded to the same stimuli. In the dehydrated rats, however, 33% (5/15) of the responding neurons were inhibited when the NaCl solution was applied to the tongue compared with only 5% (1/18) in the euhydrated rats. Iontophoretic application of angiotensin increased the spontaneous activity in 21% of those neurons tested that responded to taste. These results suggest that the state of hydration of an animal is able to change the neuronal response to substances applied to the tongue. Furthermore, it appears that these gustatory-sensitive neurons may also be related to hydromineral balance regulation since they are able to respond to angiotensin.
- Published
- 1996
- Full Text
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