22 results on '"Pierre Bousquet"'
Search Results
2. La recherche collaborative en ethnologie : est-elle toujours possible, et éthique?
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Marie-Pierre Bousquet
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éthique de la recherche ,Autochtones ,terrain ,ethnographie ,PCAP ,contrôle de la recherche ,Ethics ,BJ1-1725 - Abstract
Il existe aujourd’hui une importante quantité de lignes directrices à suivre si l’on veut faire de la recherche éthique en contexte autochtone. Dans la pratique, même avec la meilleure volonté, il est difficile de démêler ce à quoi il faut se conformer et ce qui est vraiment éthique. La voie prônée informellement dans le milieu des études autochtones est la recherche collaborative, mais est-elle toujours possible? more...
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- 2024
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Catalog
3. Des recherches sans factures : dépenser ses fonds et gérer les relations avec le service des finances
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Marie-Pierre Bousquet
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conduite responsable ,intégrité ,administration ,finances ,Ethics ,BJ1-1725 - Abstract
En matière de gestion des finances, il n’est pas toujours facile, pour les chercheurs, de suivre les normes strictes suivies par les institutions. Mais un chercheur « délinquant » aux yeux du système est-il forcément non éthique? more...
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- 2024
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4. Pharmacologic Normalization of Pancreatic Cancer-Associated Fibroblast Secretome Impairs Prometastatic Cross-Talk With MacrophagesSummary
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Rémi Samain, Alexia Brunel, Thibault Douché, Marjorie Fanjul, Stéphanie Cassant-Sourdy, Julia Rochotte, Jérôme Cros, Cindy Neuzillet, Jérôme Raffenne, Camille Duluc, Aurélie Perraud, Jérémy Nigri, Véronique Gigoux, Ivan Bieche, Matteo Ponzo, Gilles Carpentier, Ilaria Cascone, Richard Tomasini, Herbert A. Schmid, Muriel Mathonnet, Rémy Nicolle, Marie-Pierre Bousquet, Yvan Martineau, Stéphane Pyronnet, Christine Jean, and Corinne Bousquet more...
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Antimetastatic Therapy ,Cancer-Associated Fibroblasts ,Pancreatic Adenocarcinoma ,Stromal Cell Cross-Talk ,Stroma Normalization ,Macrophages ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background & Aims: Cancer-associated fibroblasts (CAFs) from pancreatic adenocarcinoma (PDA) present high protein synthesis rates. CAFs express the G-protein–coupled somatostatin receptor sst1. The sst1 agonist SOM230 blocks CAF protumoral features in vitro and in immunocompromised mice. We have explored here the therapeutic potential of SOM230, and underlying mechanisms, in immunocompetent models of murine PDA mimicking the heavy fibrotic and immunosuppressive stroma observed in patient tumors. Methods: Large-scale mass spectrometry analyses were performed on media conditioned from 9 patient PDA-derived CAF primary cultures. Spontaneous transgenic and experimental (orthotopic co-graft of tumor cells plus CAFs) PDA-bearing mice were longitudinally ultrasound-monitored for tumor and metastatic progression. Histopathology and flow cytometry analyses were performed on primary tumors and metastases. Stromal signatures were functionally validated through bioinformatics using several published, and 1 original, PDA database. Results: Proteomics on the CAF secretome showed that SOM230 controls stromal activities including inflammatory responses. Among the identified secreted proteins, we validated that colony-stimulating factor 1 (CSF-1) (a macrophage growth factor) was reduced by SOM230 in the tumor and plasma of PDA-harboring mice, alongside intratumor stromal normalization (reduced CAF and macrophage activities), and dramatic metastasis reduction. In transgenic mice, these SOM230 benefits alleviate the chemotherapy-induced (gemcitabine) immunosuppressive stroma reshaping. Mechanistically, SOM230 acts in vivo on CAFs through sst1 to disrupt prometastatic CAF production of CSF-1 and cross-talk with macrophages. We found that in patients, stromal CSF-1 was associated with aggressive PDA forms. Conclusions: We propose SOM230 as an antimetastatic therapy in PDA for its capacity to remodel the fibrotic and immunosuppressive myeloid stroma. This pharmacotherapy should benefit PDA patients treated with chemotherapies. more...
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- 2021
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5. Conformational maps of human 20S proteasomes reveal PA28- and immuno-dependent inter-ring crosstalks
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Jean Lesne, Marie Locard-Paulet, Julien Parra, Dušan Zivković, Thomas Menneteau, Marie-Pierre Bousquet, Odile Burlet-Schiltz, and Julien Marcoux
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Science - Abstract
Immune cells express immunoproteasomes (i20S), which bind to specialized regulators, contain different catalytic subunits and generate immunogenic peptides. HDX-MS—based assessment of the differences between the conformational dynamics of standard and i20s reveals specific, allosteric changes in i20S and upon regulator binding. more...
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- 2020
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6. Establishing 20S Proteasome Genetic, Translational and Post-Translational Status from Precious Biological and Patient Samples with Top-Down MS
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Angelique Sanchez Dafun, Dušan Živković, Stephen Adonai Leon-Icaza, Sophie Möller, Carine Froment, Delphine Bonnet, Adriana Almeida de Jesus, Laurent Alric, Muriel Quaranta-Nicaise, Audrey Ferrand, Céline Cougoule, Etienne Meunier, Odile Burlet-Schiltz, Frédéric Ebstein, Raphaela Goldbach-Mansky, Elke Krüger, Marie-Pierre Bousquet, and Julien Marcoux more...
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immunoproteasome ,PRAAS ,proteasome ,proteoform ,top-down proteomics ,label-free quantification ,Cytology ,QH573-671 - Abstract
The mammalian 20S catalytic core of the proteasome is made of 14 different subunits (α1-7 and β1-7) but exists as different subtypes depending on the cell type. In immune cells, for instance, constitutive catalytic proteasome subunits can be replaced by the so-called immuno-catalytic subunits, giving rise to the immunoproteasome. Proteasome activity is also altered by post-translational modifications (PTMs) and by genetic variants. Immunochemical methods are commonly used to investigate these PTMs whereby protein-tagging is necessary to monitor their effect on 20S assembly. Here, we present a new miniaturized workflow combining top-down and bottom-up mass spectrometry of immunopurified 20S proteasomes that analyze the proteasome assembly status as well as the full proteoform footprint, revealing PTMs, mutations, single nucleotide polymorphisms (SNPs) and induction of immune-subunits in different biological samples, including organoids, biopsies and B-lymphoblastoid cell lines derived from patients with proteasome-associated autoinflammatory syndromes (PRAAS). We emphasize the benefits of using top-down mass spectrometry in preserving the endogenous conformation of protein modifications, while enabling a rapid turnaround (1 h run) and ensuring high sensitivity (1–2 pmol) and demonstrate its capacity to semi-quantify constitutive and immune proteasome subunits. more...
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- 2023
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7. Introduction : Autochtones et épidémies : vides et profusion
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Marie-Pierre Bousquet
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Anthropology ,GN1-890 ,History (General) ,D1-2009 - Published
- 2022
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8. Mémoires d’épidémies : faire face à la maladie dans les récits anicinapek
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Marie-Pierre Bousquet, Maurice J. Kistabish, John Mowatt, and Laurence Hamel-Charest
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épidémies ,Anicinapek ,système de santé ,prévention ,soins ,valeurs ,epidemics ,health system ,prevention ,care ,values ,epidemias ,sistema de salud ,prevención ,cuidados ,valores ,Anthropology ,GN1-890 ,History (General) ,D1-2009 - Abstract
Depuis les années 1800, les Anicinapek ont connu diverses épidémies qui ont laissé des traces dans leur mémoire et leurs pratiques, ravivées lors du confinement du printemps 2020. Ces traces diffèrent de celles laissées dans les chroniques des auteurs allochtones : les autorités gouvernementales et ecclésiastiques les ont pensés sans ressources, sans savoirs et sans médicaments efficaces. Dans une perspective de décolonisation des savoirs, nous remettons en question l’hégémonie du discours allochtone sur les épidémies historiques chez les Autochtones en explorant comment les Anicinapek ont conceptualisé la notion d’épidémies, ainsi que les pratiques qu’ils pouvaient déployer face à elles. Cet article se fonde en priorité sur un corpus de données formé à partir de deux types de sources : des récits oraux recueillis lors d’enquêtes longitudinales ; et des documents écrits par des Anicinapek. À partir de cet angle émique, sont exposées les assises idéologiques et cosmologiques du système de santé anicinape, de la moitié du xixe siècle jusqu’aux années 1970. more...
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- 2022
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9. Les recherches-action ou collaboratives sont-elles plus éthiques? Réflexions d’une ethnologue en milieu autochtone canadien
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Marie-Pierre Bousquet
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recherches-action ,recherches collaboratives ,éthique ,autochtones ,ethnologie ,Canada ,Ethics ,BJ1-1725 - Abstract
Au Canada, depuis le début des années 2000, les recherches-action et collaboratives sont devenues de plus en plus populaires dans les sciences sociales. Dans ces recherches, les connaissances sont produites non pas seulement par les chercheurs spécialisés, mais avec les acteurs de terrain. Elles sont souvent présentées comme la panacée en matière d’éthique vis-à-vis des populations locales, surtout quand celles-ci sont en situation de marginalisation. Ces recherches sont en effet vues comme une voie d’empowerment possible. J’examine ici la façon dont ces types de recherches, appliquées à des disciplines non normatives comme la mienne, peuvent en changer le visage, à partir de mon expérience d’anthropologue en milieu amérindien au Québec. Sont-elles vraiment plus éthiques que les recherches fondamentales? Je montre les questionnements soulevés par ces modèles, qui peuvent changer les façons de pratiquer mon métier, en prêtant une attention particulière à l’engagement du chercheur, à la validité et la solidité des méthodologies et des épistémologies, ainsi qu’aux degrés de participation des informateurs, tout cela dans le cadre des règles éthiques formulées par les conseils subventionnaires canadiens et par les Autochtones eux-mêmes. more...
- Published
- 2019
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10. Au-delà de la bureaucratie obligatoire : comment bien travailler avec des comités d’éthique de la recherche
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Marie-Pierre Bousquet and Bryn Williams-Jones
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éthique de la recherche ,CÉR ,université ,vision négative ,mandat ,chercheur ,Ethics ,BJ1-1725 - Abstract
Les comités d’éthique de la recherche (CÉR) universitaire, même s’ils sont bien établis en Amérique du nord depuis les années 1980, ont encore parfois mauvaise réputation au sein des chercheurs. Parfois, ils sont vus par les membres de la communauté scientifique comme un système bureaucratique voué à empêcher ou à ralentir la recherche et ne comprenant pas la réalité des chercheurs. Cette vision négative relève souvent de la mécompréhension 1) de la part des chercheurs et 2) de certains CÉR de ce qu’est le mandat d’un CÉR et de la façon dont il doit fonctionner. Fondée sur une expérience d’une présidente d’un CÉR et d’un bioéthicien, cette foire aux questions vise à démystifier l’éthique de la recherche pour que les chercheurs et les CÉR puissent collaborer dans l’avancement des connaissances, tout en assurant une conduite de recherche éthique et responsable. more...
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- 2018
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11. Pharmacological targeting of the protein synthesis mTOR/4E‐BP1 pathway in cancer‐associated fibroblasts abrogates pancreatic tumour chemoresistance
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Camille Duluc, Siham Moatassim‐Billah, Mounira Chalabi‐Dchar, Aurélie Perraud, Rémi Samain, Florence Breibach, Marion Gayral, Pierre Cordelier, Marie‐Bernadette Delisle, Marie‐Pierre Bousquet‐Dubouch, Richard Tomasini, Herbert Schmid, Muriel Mathonnet, Stéphane Pyronnet, Yvan Martineau, and Corinne Bousquet more...
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cancer‐associated fibroblasts ,chemoresistance ,pancreatic cancer ,pharmacotherapy ,protein synthesis and secretion ,Medicine (General) ,R5-920 ,Genetics ,QH426-470 - Abstract
Abstract Pancreatic ductal adenocarcinoma (PDAC) is extremely stroma‐rich. Cancer‐associated fibroblasts (CAFs) secrete proteins that activate survival and promote chemoresistance of cancer cells. Our results demonstrate that CAF secretome‐triggered chemoresistance is abolished upon inhibition of the protein synthesis mTOR/4E‐BP1 regulatory pathway which we found highly activated in primary cultures of α‐SMA‐positive CAFs, isolated from human PDAC resections. CAFs selectively express the sst1 somatostatin receptor. The SOM230 analogue (Pasireotide) activates the sst1 receptor and inhibits the mTOR/4E‐BP1 pathway and the resultant synthesis of secreted proteins including IL‐6. Consequently, tumour growth and chemoresistance in nude mice xenografted with pancreatic cancer cells and CAFs, or with pieces of resected human PDACs, are reduced when chemotherapy (gemcitabine) is combined with SOM230 treatment. While gemcitabine alone has marginal effects, SOM230 is permissive to gemcitabine‐induced cancer cell apoptosis and acts as an antifibrotic agent. We propose that selective inhibition of CAF protein synthesis with sst1‐directed pharmacological compounds represents an anti‐stromal‐targeted therapy with promising chemosensitization potential. more...
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- 2015
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12. Deciphering preferential interactions within supramolecular protein complexes: the proteasome case
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Bertrand Fabre, Thomas Lambour, Luc Garrigues, François Amalric, Nathalie Vigneron, Thomas Menneteau, Alexandre Stella, Bernard Monsarrat, Benoît Van den Eynde, Odile Burlet‐Schiltz, and Marie‐Pierre Bousquet‐Dubouch more...
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affinity purification ,correlation profiling ,label‐free quantitative proteomics ,mass spectrometry ,Biology (General) ,QH301-705.5 ,Medicine (General) ,R5-920 - Abstract
Abstract In eukaryotic cells, intracellular protein breakdown is mainly performed by the ubiquitin–proteasome system. Proteasomes are supramolecular protein complexes formed by the association of multiple sub‐complexes and interacting proteins. Therefore, they exhibit a very high heterogeneity whose function is still not well understood. Here, using a newly developed method based on the combination of affinity purification and protein correlation profiling associated with high‐resolution mass spectrometry, we comprehensively characterized proteasome heterogeneity and identified previously unknown preferential associations within proteasome sub‐complexes. In particular, we showed for the first time that the two main proteasome subtypes, standard proteasome and immunoproteasome, interact with a different subset of important regulators. This trend was observed in very diverse human cell types and was confirmed by changing the relative proportions of both 20S proteasome forms using interferon‐γ. The new method developed here constitutes an innovative and powerful strategy that could be broadly applied for unraveling the dynamic and heterogeneous nature of other biologically relevant supramolecular protein complexes. more...
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- 2015
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13. The Euler Equation in the Multiple Integrals Calculus of Variations.
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Pierre Bousquet
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- 2013
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14. Anthropological perspectives on Miyupimaatisiiun and the integration of oral health in primary care in the Cree communities of Northern Quebec.
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Shrivastava, Richa, Campeau, Roxane, Couturier, Yves, Torrie, Jill, Girard, Felix, Marie-Pierre, Bousquet, and Emami, Elham
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INTERPROFESSIONAL relations ,PRIMARY care ,MEDICAL care ,PROFESSIONAL relationships ,CULTURAL competence ,ACCULTURATION ,MEDICAL communication - Abstract
The integration of primary oral health care has a pivotal role in improving oral health outcomes and providing accessible and affordable health care. This article contributes to the deep understanding of the cultural aspects of the integration of oral health into primary health care at an Indigenous health organization. Proceeding from a collaborative and interdisciplinary research project evaluating the integration of oral health care within primary care in Eeyou Istchee, this research is based on group discussions (6) and individual interviews (36) with 74 participants (care providers, administrators, and patients) held in four Eastern James Bay Cree communities. This study anthropologically explored participants' perceptions about primary health care conceptualizations, culturally based approaches, and experiences of oral care services at this organization using a "two-eyed seeing" Indigenous framework. The study identified three key factors related to the integration of primary oral health care: Cree perception of primary health and oral health care, cultural safety, and health provider–patient communication and the role of silence. Study findings reflected a dichotomy of perception of primary health care and the relevant units of care between the Cree structural and cultural perspective and the non-Cree professional perspective. The Cree people perceived "household" as a unit of care in comparison to non-Cree who viewed "health care services" as units of care. Our results also underline the role of cultural safety agents to address the needs for cultural competence and the role of silence as implicit cultural protocol. Our anthropological analysis illustrates the potential for increasing the level of appreciation for both users and workers in oral care in the future by ameliorating communication skills and intercultural knowledge. [ABSTRACT FROM AUTHOR] more...
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- 2020
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15. Scaled-Down Purification Protocol To Access Proteomic Analysis of 20S Proteasome from Human Tissue Samples: Comparison of Normal and Tumor Colorectal Cells.
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Manuelle Ducoux-Petit, Franck Brichory, Marie-Pierre Bousquet-Dubouch, Odile Burlet-Schiltz, Jean-François Haeuw, Bernard Monsarrat, and Sandrine Uttenweiler-Joseph
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- 2008
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16. Local Lipschitz continuity of solutions of non-linear elliptic differential-functional equations.
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Pierre Bousquet
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MATHEMATICAL formulas , *ELLIPTIC differential equations , *VECTOR analysis , *CONVEX functions , *LIPSCHITZ continuity - Abstract
The object of this paper is to prove existence and regularity results for non-linear elliptic differential-functional equations of the form diva(?u)+F[u](x)=0, over the functions u?W1,1(?) that assume given boundary values ? on [Formula: see text][Formula: see text] The vector field a:Rn?Rnsatisfies an ellipticity condition and for a fixed x, F[u](x) denotes a non-linear functional of u. In considering the same problem, Hartman and Stampacchia?[Acta Math. 115 (1966) 271?310] have obtained existence results in the space of uniformly Lipschitz continuous functions when ? satisfies the classical bounded slope condition. In a variational context, Clarke?[Ann. Sc. Norm. Super. Pisa Cl. Sci. 4 (2005) 511?530] has introduced a new type of hypothesis on the boundary condition ?: the lower (or upper) bounded slope condition. This condition, which is less restrictive than the previous one, is satisfied if ? is the restriction to [Formula: see text][Formula: see text] of a convex function. We show that if a and F satisfy hypotheses similar to those of Hartman and Stampacchia, the lower bounded slope condition implies the existence of solutions in the space of locally Lipschitz continuous functions on ?. [ABSTRACT FROM AUTHOR] more...
- Published
- 2007
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17. A quantitative proteomic approach using two-dimensional gel electrophoresis and isotope-coded affinity tag labeling for studying human 20S proteasome heterogeneity.
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Carine Froment, Sandrine Uttenweiler-Joseph, Marie-Pierre Bousquet-Dubouch, Mariette Matondo, Jean-Philippe Borges, Charlotte Esmenjaud, Christelle Lacroix, Bernard Monsarrat, and Odile Burlet-Schiltz more...
- Published
- 2005
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18. Druggable redox pathways against Mycobacterium abscessus in cystic fibrosis patient-derived airway organoids.
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Stephen Adonai Leon-Icaza, Salimata Bagayoko, Romain Vergé, Nino Iakobachvili, Chloé Ferrand, Talip Aydogan, Célia Bernard, Angelique Sanchez Dafun, Marlène Murris-Espin, Julien Mazières, Pierre Jean Bordignon, Serge Mazères, Pascale Bernes-Lasserre, Victoria Ramé, Jean-Michel Lagarde, Julien Marcoux, Marie-Pierre Bousquet, Christian Chalut, Christophe Guilhot, Hans Clevers, Peter J Peters, Virginie Molle, Geanncarlo Lugo-Villarino, Kaymeuang Cam, Laurence Berry, Etienne Meunier, and Céline Cougoule more...
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Mycobacterium abscessus (Mabs) drives life-shortening mortality in cystic fibrosis (CF) patients, primarily because of its resistance to chemotherapeutic agents. To date, our knowledge on the host and bacterial determinants driving Mabs pathology in CF patient lung remains rudimentary. Here, we used human airway organoids (AOs) microinjected with smooth (S) or rough (R-)Mabs to evaluate bacteria fitness, host responses to infection, and new treatment efficacy. We show that S Mabs formed biofilm, and R Mabs formed cord serpentines and displayed a higher virulence. While Mabs infection triggers enhanced oxidative stress, pharmacological activation of antioxidant pathways resulted in better control of Mabs growth and reduced virulence. Genetic and pharmacological inhibition of the CFTR is associated with better growth and higher virulence of S and R Mabs. Finally, pharmacological activation of antioxidant pathways inhibited Mabs growth, at least in part through the quinone oxidoreductase NQO1, and improved efficacy in combination with cefoxitin, a first line antibiotic. In conclusion, we have established AOs as a suitable human system to decipher mechanisms of CF-driven respiratory infection by Mabs and propose boosting of the NRF2-NQO1 axis as a potential host-directed strategy to improve Mabs infection control. more...
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- 2023
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19. Faire de la recherche en ethnologie/ethnolinguistique dans un contexte totalitaire : les défis d’étudier des sujets sensibles
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Marie-Pierre Bousquet
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anthropologie ,risques ,sujets sensibles ,ethnologie ,ethnolinguistique ,Ethics ,BJ1-1725 - Abstract
La recherche ethnologique et ethnolinguistique peut poser un large éventail de défis éthiques différents pour les chercheurs et les communautés dans lesquelles ils travaillent. Les ethnologues et les ethnolinguistes étudient les sociétés humaines sous différents angles pour comprendre leurs caractères culturels, leurs variabilités linguistiques, etc. Ces recherches peuvent faire progresser la compréhension que l’on a des groupes sociaux et contribuer à la production de connaissances, et peuvent même parfois être bénéfiques pour certaines communautés. Mais elle peut aussi créer des risques pour les participants et les communautés (par exemple perte de la vie privée, stigmatisation, persécution), et pour les chercheurs eux-mêmes (par exemple perte d'accès à une zone de terrain, perte de contrôle du processus et des résultats de la recherche). Ces risques et autres défis éthiques, ainsi que les moyens d'y faire face, méritent une attention particulière de la part des ethnologues et de l'ethnolinguistique. more...
- Published
- 2020
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20. The intermediate proteasome is constitutively expressed in pancreatic beta cells and upregulated by stimulatory, low concentrations of interleukin 1 β.
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Muhammad Saad Khilji, Danielle Verstappen, Tina Dahlby, Michala Cecilie Burstein Prause, Celina Pihl, Sophie Emilie Bresson, Tenna Holgersen Bryde, Phillip Alexander Keller Andersen, Kristian Klindt, Dusan Zivkovic, Marie-Pierre Bousquet-Dubouch, Björn Tyrberg, Thomas Mandrup-Poulsen, and Michal Tomasz Marzec more...
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Medicine ,Science - Abstract
A central and still open question regarding the pathogenesis of autoimmune diseases, such as type 1 diabetes, concerns the processes that underlie the generation of MHC-presented autoantigenic epitopes that become targets of autoimmune attack. Proteasomal degradation is a key step in processing of proteins for MHC class I presentation. Different types of proteasomes can be expressed in cells dictating the repertoire of peptides presented by the MHC class I complex. Of particular interest for type 1 diabetes is the proteasomal configuration of pancreatic β cells, as this might facilitate autoantigen presentation by β cells and thereby their T-cell mediated destruction. Here we investigated whether so-called inducible subunits of the proteasome are constitutively expressed in β cells, regulated by inflammatory signals and participate in the formation of active intermediate or immuno-proteasomes. We show that inducible proteasomal subunits are constitutively expressed in human and rodent islets and an insulin-secreting cell-line. Moreover, the β5i subunit is incorporated into active intermediate proteasomes that are bound to 19S or 11S regulatory particles. Finally, inducible subunit expression along with increase in total proteasome activities are further upregulated by low concentrations of IL-1β stimulating proinsulin biosynthesis. These findings suggest that the β cell proteasomal repertoire is more diverse than assumed previously and may be highly responsive to a local inflammatory islet environment. more...
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- 2020
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21. Top-Down and Intact Protein Mass Spectrometry Data Visualization for Proteoform Analysis Using VisioProt-MS
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Jean Lesne, Marie-Pierre Bousquet, Julien Marcoux, and Marie Locard-Paulet
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Biology (General) ,QH301-705.5 - Abstract
The rise of intact protein analysis by mass spectrometry (MS) was accompanied by an increasing need for flexible tools allowing data visualization and analysis. These include inspection of the deconvoluted molecular weights of the proteoforms eluted alongside liquid chromatography (LC) through their representation in three-dimensional (3D) liquid chromatography coupled to mass spectrometry (LC-MS) maps (plots of deconvoluted molecular weights, retention times, and intensity of the MS signal). With this aim, we developed a free and open-source web application named VisioProt-MS ( https://masstools.ipbs.fr/mstools/visioprot-ms/ ). VisioProt-MS is highly compatible with many algorithms and software developed by the community to integrate and deconvolute top-down and intact protein MS data. Its dynamic and user-friendly features greatly facilitate analysis through several graphical representations dedicated to MS and tandem mass spectrometry (MS/MS) analysis of proteoforms in complex samples. Here, we will illustrate the importance of LC-MS map visualization to optimize top-down acquisition/search parameters and analyze intact protein MS data. We will go through the main features of VisioProt-MS using the human proteasomal 20S core particle as a user-case. more...
- Published
- 2019
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22. Comparison of label-free quantification methods for the determination of protein complexes subunits stoichiometry
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Bertrand Fabre, Thomas Lambour, David Bouyssié, Thomas Menneteau, Bernard Monsarrat, Odile Burlet-Schiltz, and Marie-Pierre Bousquet-Dubouch
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26S proteasome ,Affinity purification mass spectrometry (AP-MS) ,iBAQ ,Top3 ,Spectral counting ,Genetics ,QH426-470 - Abstract
Protein complexes are the main molecular machines that support all major cellular pathways and their in-depth characterization are essential to understand their functions. Determining the stoichiometry of the different subunits of a protein complex still remains challenging. Recently, many label-free quantitative proteomic approaches have been developed to study the composition of protein complexes. It is therefore of great interest to evaluate these different methods in a stoichiometry oriented objective. Here we compare the ability of four absolute quantitative label-free methods currently used in proteomic studies to determine the stoichiometry of a well-characterized protein complex, the 26S proteasome. more...
- Published
- 2014
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