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Paret R, Talarmin J, Le Bourgeois A, Guillerm G, Gastinne T, Couturier M, Boutoille D, Ansart S, Gaborit B. Arrêt de l’antibiothérapie en cours de neutropénie pour fièvre d’origine indéterminée en hématologie stérile : RELAPS, une étude de cohorte bicentrique descriptive. Med Mal Infect 2020. [DOI: 10.1016/j.medmal.2020.06.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Guiot A, Couturier M, Tebib JG, Abouaf L, Coury F. [Antimalarial drug retinopathy]. Rev Med Interne 2018; 39:364-368. [PMID: 29496271 DOI: 10.1016/j.revmed.2018.02.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 01/23/2018] [Accepted: 02/04/2018] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Antimalarial drugs are largely used for the treatment of various systemic diseases. They can cause toxic retinopathy, which can lead to blindness. OBSERVATION We report the case of a 32-year-old male with a systemic lupus erythematosus treated with hydroxychloroquine 400mg per day and then chloroquine 300mg per day during 8 and 9years respectively. Eighteen months after his latest visual examination, the patient experienced bilateral vision loss. Fundus examination revealed a bull's eye maculopathy. Additional tests including multifocal electroretinogram showed severe bilateral functional impairment in the parafoveal area leading to diagnosis of severe toxic retinopathy induced by antimalarial drugs. DISCUSSION In 2016, the American Academy of Ophthalmology revised the previous 2011 recommendations concerning early retinal toxicity screening strategy which should be first based on both automated 10-2 visual fields and spectral-domain optical coherence tomography (SD OCT). Multifocal electroretinogram can be more helpful for diagnostic confirmation rather than screening. Although these recommendations are essential, they are not well known in clinical practice.
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Affiliation(s)
- A Guiot
- Hospices civils de Lyon, centre Hospitalier Lyon Sud, département de Rhumatologie, 69310 Pierre-Bénite, France; Université Lyon 1, Lyon, France.
| | - M Couturier
- Hospices civils de Lyon, centre Hospitalier Lyon Sud, département de Rhumatologie, 69310 Pierre-Bénite, France; Université Lyon 1, Lyon, France
| | - J G Tebib
- Hospices civils de Lyon, centre Hospitalier Lyon Sud, département de Rhumatologie, 69310 Pierre-Bénite, France; Université Lyon 1, Lyon, France
| | - L Abouaf
- Hospices civils de Lyon, unité de neuro-ophtalmologie, hôpital neurologique Pierre-Wertheimer, groupement hospitalier Est, 69500 Bron, France
| | - F Coury
- Hospices civils de Lyon, centre Hospitalier Lyon Sud, département de Rhumatologie, 69310 Pierre-Bénite, France; Université Lyon 1, Lyon, France
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3
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Wong MT, Wang W, Couturier M, Razeq FM, Lombard V, Lapebie P, Edwards EA, Terrapon N, Henrissat B, Master ER. Comparative Metagenomics of Cellulose- and Poplar Hydrolysate-Degrading Microcosms from Gut Microflora of the Canadian Beaver ( Castor canadensis) and North American Moose ( Alces americanus) after Long-Term Enrichment. Front Microbiol 2017; 8:2504. [PMID: 29326667 PMCID: PMC5742341 DOI: 10.3389/fmicb.2017.02504] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 12/01/2017] [Indexed: 11/13/2022] Open
Abstract
To identify carbohydrate-active enzymes (CAZymes) that might be particularly relevant for wood fiber processing, we performed a comparative metagenomic analysis of digestive systems from Canadian beaver (Castor canadensis) and North American moose (Alces americanus) following 3 years of enrichment on either microcrystalline cellulose or poplar hydrolysate. In total, 9,386 genes encoding CAZymes and carbohydrate-binding modules (CBMs) were identified, with up to half predicted to originate from Firmicutes, Bacteroidetes, Chloroflexi, and Proteobacteria phyla, and up to 17% from unknown phyla. Both PCA and hierarchical cluster analysis distinguished the annotated glycoside hydrolase (GH) distributions identified herein, from those previously reported for grass-feeding mammals and herbivorous foragers. The CAZyme profile of moose rumen enrichments also differed from a recently reported moose rumen metagenome, most notably by the absence of GH13-appended dockerins. Consistent with substrate-driven convergence, CAZyme profiles from both poplar hydrolysate-fed cultures differed from cellulose-fed cultures, most notably by increased numbers of unique sequences belonging to families GH3, GH5, GH43, GH53, and CE1. Moreover, pairwise comparisons of moose rumen enrichments further revealed higher counts of GH127 and CE15 families in cultures fed with poplar hydrolysate. To expand our scope to lesser known carbohydrate-active proteins, we identified and compared multi-domain proteins comprising both a CBM and domain of unknown function (DUF) as well as proteins with unknown function within the 416 predicted polysaccharide utilization loci (PULs). Interestingly, DUF362, identified in iron-sulfur proteins, was consistently appended to CBM9; on the other hand, proteins with unknown function from PULs shared little identity unless from identical PULs. Overall, this study sheds new light on the lignocellulose degrading capabilities of microbes originating from digestive systems of mammals known for fiber-rich diets, and highlights the value of enrichment to select new CAZymes from metagenome sequences for future biochemical characterization.
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Affiliation(s)
- Mabel T Wong
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Weijun Wang
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Marie Couturier
- Centre de Recherches sur les Macromolécules Végétales - Université Grenoble Alpes, Grenoble, France.,Centre National de la Recherche Scientifique, Centre de Recherches sur les Macromolécules Végétales, Grenoble, France
| | - Fakhria M Razeq
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Vincent Lombard
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Marseille, France.,UMR 7257, Centre National de la Recherche Scientifique, Marseille, France
| | - Pascal Lapebie
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Marseille, France
| | - Elizabeth A Edwards
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Nicolas Terrapon
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Marseille, France
| | - Bernard Henrissat
- UMR 7257, Centre National de la Recherche Scientifique, Marseille, France.,Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Emma R Master
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.,Department of Bioproducts and Biosystems, Aalto University, Espoo, Finland
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Eberst G, Guillien A, Goirand F, Bonniaud P, Burgy O, Soumagne T, Couturier M, Gondouin A, Laurent L, Dalphin J, Perruche S, Degano B. La résolution de l’inflammation dans la fibrose pulmonaire idiopathique avec un nouvel immunomodulateur. Rev Mal Respir 2017. [DOI: 10.1016/j.rmr.2016.10.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Wong MT, Wang W, Lacourt M, Couturier M, Edwards EA, Master ER. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus). Front Microbiol 2016; 7:961. [PMID: 27446004 PMCID: PMC4914502 DOI: 10.3389/fmicb.2016.00961] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 06/03/2016] [Indexed: 02/01/2023] Open
Abstract
Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.
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Affiliation(s)
- Mabel T Wong
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
| | - Weijun Wang
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
| | - Michael Lacourt
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
| | - Marie Couturier
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
| | - Elizabeth A Edwards
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
| | - Emma R Master
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto ON, Canada
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Bonnefoy F, Vallion R, Couturier M, Daoui A, Toussirot E, Perruche S. SAT0032 Pro-Resolving Mediators Issued from Apoptotic Cell Efferocytosis (SuperMApo) Modulate APC Properties toward A Tolerogenic Profile: Efficacy in The Treatment of Collagen- Induced Arthritis. Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.4715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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7
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Couturier M, Tangthirasunun N, Ning X, Brun S, Gautier V, Bennati-Granier C, Silar P, Berrin JG. Plant biomass degrading ability of the coprophilic ascomycete fungus Podospora anserina. Biotechnol Adv 2016; 34:976-983. [PMID: 27263000 DOI: 10.1016/j.biotechadv.2016.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 05/11/2016] [Accepted: 05/27/2016] [Indexed: 12/22/2022]
Abstract
The degradation of plant biomass is a major challenge towards the production of bio-based compounds and materials. As key lignocellulolytic enzyme producers, filamentous fungi represent a promising reservoir to tackle this challenge. Among them, the coprophilous ascomycete Podospora anserina has been used as a model organism to study various biological mechanisms because its genetics are well understood and controlled. In 2008, the sequencing of its genome revealed a great diversity of enzymes targeting plant carbohydrates and lignin. Since then, a large array of lignocellulose-acting enzymes has been characterized and genetic analyses have enabled the understanding of P. anserina metabolism and development on plant biomass. Overall, these research efforts shed light on P. anserina strategy to unlock recalcitrant lignocellulose deconstruction.
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Affiliation(s)
- Marie Couturier
- INRA, Aix Marseille Université, Polytech Marseille, UMR 1163, Biodiversité et Biotechnologie Fongiques, F-13288 Marseille, France
| | - Narumon Tangthirasunun
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Diderot, 35, rue Hélène Brion, F-75205 Paris, France
| | - Xie Ning
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Diderot, 35, rue Hélène Brion, F-75205 Paris, France
| | - Sylvain Brun
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Diderot, 35, rue Hélène Brion, F-75205 Paris, France
| | - Valérie Gautier
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Diderot, 35, rue Hélène Brion, F-75205 Paris, France
| | - Chloé Bennati-Granier
- INRA, Aix Marseille Université, Polytech Marseille, UMR 1163, Biodiversité et Biotechnologie Fongiques, F-13288 Marseille, France
| | - Philippe Silar
- Laboratoire Interdisciplinaire des Energies de Demain, Université Paris Diderot, 35, rue Hélène Brion, F-75205 Paris, France.
| | - Jean-Guy Berrin
- INRA, Aix Marseille Université, Polytech Marseille, UMR 1163, Biodiversité et Biotechnologie Fongiques, F-13288 Marseille, France.
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8
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Gupta VK, Kubicek CP, Berrin JG, Wilson DW, Couturier M, Berlin A, Filho EXF, Ezeji T. Fungal Enzymes for Bio-Products from Sustainable and Waste Biomass. Trends Biochem Sci 2016; 41:633-645. [PMID: 27211037 DOI: 10.1016/j.tibs.2016.04.006] [Citation(s) in RCA: 134] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 04/13/2016] [Accepted: 04/22/2016] [Indexed: 12/19/2022]
Abstract
Lignocellulose, the most abundant renewable carbon source on earth, is the logical candidate to replace fossil carbon as the major biofuel raw material. Nevertheless, the technologies needed to convert lignocellulose into soluble products that can then be utilized by the chemical or fuel industries face several challenges. Enzymatic hydrolysis is of major importance, and we review the progress made in fungal enzyme technology over the past few years with major emphasis on (i) the enzymes needed for the conversion of polysaccharides (cellulose and hemicellulose) into soluble products, (ii) the potential uses of lignin degradation products, and (iii) current progress and bottlenecks for the use of the soluble lignocellulose derivatives in emerging biorefineries.
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Affiliation(s)
- Vijai K Gupta
- Molecular Glycobiotechnology Group, Discipline of Biochemistry, National University of Ireland Galway, Galway City, Ireland.
| | - Christian P Kubicek
- Biotechnology and Microbiology, Institute of Chemical Engineering, Technische Universität Wien, Gumpendorferstrasse, 1060 Wien, Austria
| | - Jean-Guy Berrin
- Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche (UMR) 1163-Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France; Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France
| | - David W Wilson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Marie Couturier
- Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche (UMR) 1163-Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France; Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France
| | - Alex Berlin
- Novozymes, Inc., 1445 Drew Ave, Davis CA 95618 USA
| | - Edivaldo X F Filho
- Laboratory of Enzymology, Department of Cell Biology, University of Brasilia, Asa Norte, 70910-900 Brasilia, DF Brazil
| | - Thaddeus Ezeji
- Biotechnology and Fermentation Group, Department of Animal Sciences, Ohio State University and Ohio Agricultural Research and Development Center (OARDC), Madison Avenue, Wooster, OH 44691, USA
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9
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Lamarthée B, Malard F, Gamonet C, Bossard C, Couturier M, Renauld JC, Mohty M, Saas P, Gaugler B. Donor interleukin-22 and host type I interferon signaling pathway participate in intestinal graft-versus-host disease via STAT1 activation and CXCL10. Mucosal Immunol 2016; 9:309-21. [PMID: 26153763 DOI: 10.1038/mi.2015.61] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 05/28/2015] [Indexed: 02/04/2023]
Abstract
Acute graft-versus-host disease (aGVHD) remains a major complication following allogeneic hematopoietic cell transplantation, limiting the success of this therapy. We previously reported that interleukin-22 (IL-22) participates to aGVHD development, but the underlying mechanisms of its contribution remain poorly understood. In this study, we analyzed the mechanism of the pathological function of IL-22 in intestinal aGVHD. Ex-vivo colon culture experiments indicated that IL-22 was able to induce Th1-like inflammation via signal transducer and activator of transcription factor-1 (STAT1) and CXCL10 induction in the presence of type I interferon (IFN). To evaluate a potential synergy between IL-22 and type I IFN in aGVHD, we transplanted recipient mice, either wild-type (WT) or type I IFN receptor deficient (IFNAR(-/-)), with bone marrow cells and WT or IL-22 deficient (IL-22(-/-)) T cells. We observed a decreased GVHD severity in IFNAR(-/-) recipient of IL-22(-/-) T cells, which was associated with a lower level of STAT1 activation and reduced CXCL10 expression in the large intestine. Finally, immunohistochemistry staining of STAT1 performed on gastrointestinal biopsies of 20 transplanted patients showed exacerbated STAT1 activation in gastrointestinal tissues of patients with aGVHD as compared with those without aGVHD. Thus, interfering with both IL-22 and type I IFN signaling may provide a novel approach to limit aGVHD.
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Affiliation(s)
- B Lamarthée
- INSERM UMR1098, Besançon, France
- Université de Bourgogne Franche-Comté, UMR 1098, SFR FED 4234, Besançon, France
- EFS Bourgogne Franche-Comté, UMR 1098, Besançon, France
| | - F Malard
- Centre de Recherche Saint-Antoine, INSERM UMRs938, Paris, France
- Université Pierre et Marie Curie, Paris, France
- Service d'Hématologie Clinique, Hôpital Saint-Antoine, Paris, France
| | - C Gamonet
- INSERM UMR1098, Besançon, France
- Université de Bourgogne Franche-Comté, UMR 1098, SFR FED 4234, Besançon, France
- EFS Bourgogne Franche-Comté, UMR 1098, Besançon, France
| | - C Bossard
- EA4273 Biometadys, Faculté de médecine, Université de Nantes, Nantes, France
- Service d'Anatomie et Cytologie Pathologique, CHU de Nantes, Nantes, France
| | - M Couturier
- INSERM UMR1098, Besançon, France
- Université de Bourgogne Franche-Comté, UMR 1098, SFR FED 4234, Besançon, France
- EFS Bourgogne Franche-Comté, UMR 1098, Besançon, France
| | - J-C Renauld
- Ludwig Institute for Cancer Research and Experimental Medicine Unit, Université Catholique de Louvain, Brussels, Belgium
| | - M Mohty
- Centre de Recherche Saint-Antoine, INSERM UMRs938, Paris, France
- Université Pierre et Marie Curie, Paris, France
- Service d'Hématologie Clinique, Hôpital Saint-Antoine, Paris, France
| | - P Saas
- INSERM UMR1098, Besançon, France
- Université de Bourgogne Franche-Comté, UMR 1098, SFR FED 4234, Besançon, France
- EFS Bourgogne Franche-Comté, UMR 1098, Besançon, France
| | - B Gaugler
- INSERM UMR1098, Besançon, France
- Université de Bourgogne Franche-Comté, UMR 1098, SFR FED 4234, Besançon, France
- EFS Bourgogne Franche-Comté, UMR 1098, Besançon, France
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Couturier M, Annweiler T, Bertoletti L, Barral FG. Successful retrieval of a long-lasting temporary inferior vena cava filter. Diagn Interv Imaging 2016; 97:481-2. [PMID: 26780884 DOI: 10.1016/j.diii.2015.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 11/30/2015] [Accepted: 12/02/2015] [Indexed: 01/10/2023]
Affiliation(s)
- M Couturier
- Service de médecine vasculaire et thérapeutique, hôpital Nord, CHU de Saint-Étienne, avenue A.-Raimond, 42055 Saint-Étienne, France.
| | - T Annweiler
- Service de radiologie centrale, hôpital Nord, CHU de Saint-Étienne, avenue A.-Raimond, 42055 Saint-Étienne, France
| | - L Bertoletti
- Service de médecine vasculaire et thérapeutique, hôpital Nord, CHU de Saint-Étienne, avenue A.-Raimond, 42055 Saint-Étienne, France; Inserm, SAINBIOSE, U1059, dysfonction vasculaire et hémostase, université Jean-Monnet, 42055 Saint-Étienne, France
| | - F-G Barral
- Service de radiologie centrale, hôpital Nord, CHU de Saint-Étienne, avenue A.-Raimond, 42055 Saint-Étienne, France; Inserm, SAINBIOSE, U1059, dysfonction vasculaire et hémostase, université Jean-Monnet, 42055 Saint-Étienne, France
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Marchetti R, Berrin JG, Couturier M, Ul Qader SA, Molinaro A, Silipo A. NMR analysis of the binding mode of two fungal endo-β-1,4-mannanases from GH5 and GH26 families. Org Biomol Chem 2016; 14:314-22. [DOI: 10.1039/c5ob01851j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A different mode of action among two endo-β-1,4 mannanases from Podospora anserina has been revealed through an accurate NMR analysis.
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Affiliation(s)
- Roberta Marchetti
- Department of Chemical Sciences
- Università di Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Naples
- Italy
| | | | | | - Shah Ali Ul Qader
- Department of Chemical Sciences
- Università di Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Naples
- Italy
| | - Antonio Molinaro
- Department of Chemical Sciences
- Università di Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Naples
- Italy
| | - Alba Silipo
- Department of Chemical Sciences
- Università di Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Naples
- Italy
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Couturier M, Mathieu Y, Li A, Navarro D, Drula E, Haon M, Grisel S, Ludwig R, Berrin JG. Characterization of a new aryl-alcohol oxidase secreted by the phytopathogenic fungus Ustilago maydis. Appl Microbiol Biotechnol 2015; 100:697-706. [DOI: 10.1007/s00253-015-7021-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/12/2015] [Accepted: 09/06/2015] [Indexed: 10/22/2022]
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Bonnefoy F, Vallion R, Couturier M, Daoui A, Toussirot E, Perruche S. AB0118 Pro-Resolving Mediators Issued from Apoptotic Cell Efferocytosis (Supermapo) Modulate APC Properties Toward a Tolerogenic Profile: Efficacy in the Treatment of Collagen-Induced Arthritis. Ann Rheum Dis 2015. [DOI: 10.1136/annrheumdis-2015-eular.5385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Couturier M, Navarro D, Chevret D, Henrissat B, Piumi F, Ruiz-Dueñas FJ, Martinez AT, Grigoriev IV, Riley R, Lipzen A, Berrin JG, Master ER, Rosso MN. Enhanced degradation of softwood versus hardwood by the white-rot fungus Pycnoporus coccineus. Biotechnol Biofuels 2015; 8:216. [PMID: 26692083 PMCID: PMC4683735 DOI: 10.1186/s13068-015-0407-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 12/03/2015] [Indexed: 05/11/2023]
Abstract
BACKGROUND White-rot basidiomycete fungi are potent degraders of plant biomass, with the ability to mineralize all lignocellulose components. Recent comparative genomics studies showed that these fungi use a wide diversity of enzymes for wood degradation. Deeper functional analyses are however necessary to understand the enzymatic mechanisms leading to lignocellulose breakdown. The Polyporale fungus Pycnoporus coccineus BRFM310 grows well on both coniferous and deciduous wood. In the present study, we analyzed the early response of the fungus to softwood (pine) and hardwood (aspen) feedstocks and tested the effect of the secreted enzymes on lignocellulose deconstruction. RESULTS Transcriptomic and proteomic analyses revealed that P. coccineus grown separately on pine and aspen displayed similar sets of transcripts and enzymes implicated in lignin and polysaccharide degradation. In particular, the expression of lignin-targeting oxidoreductases, such as manganese peroxidases, increased upon cultivation on both woods. The sets of enzymes secreted during growth on both pine and aspen were more efficient in saccharide release from pine than from aspen, and characterization of the residual solids revealed polysaccharide conversion on both pine and aspen fiber surfaces. CONCLUSION The combined analysis of soluble sugars and solid residues showed the suitability of P. coccineus secreted enzymes for softwood degradation. Analyses of solubilized products and residual surface chemistries of enzyme-treated wood samples pointed to differences in fiber penetration by different P. coccineus secretomes. Accordingly, beyond the variety of CAZymes identified in P. coccineus genome, transcriptome and secretome, we discuss several parameters such as the abundance of manganese peroxidases and the potential role of cytochrome P450s and pectin degradation on the efficacy of fungi for softwood conversion.
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Affiliation(s)
- Marie Couturier
- />Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />INRA, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Polytech’Marseille, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON Canada
| | - David Navarro
- />Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />INRA, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Polytech’Marseille, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
| | - Didier Chevret
- />INRA, UMR1319 Micalis, Plateforme d’Analyse Protéomique de Paris Sud-Ouest, 78352 Jouy-En-Josas, France
| | - Bernard Henrissat
- />Architecture et Fonction des Macromolécules Biologiques (AFMB), UMR 7257 CNRS, Université Aix-Marseille, 13288 Marseille, France
- />Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
- />INRA, USC 1408 AFMB, 13288 Marseille, France
| | - François Piumi
- />Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />INRA, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Polytech’Marseille, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
| | | | | | - Igor V. Grigoriev
- />US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Robert Riley
- />US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Anna Lipzen
- />US Department of Energy Joint Genome Institute (JGI), Walnut Creek, CA USA
| | - Jean-Guy Berrin
- />Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />INRA, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Polytech’Marseille, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
| | - Emma R. Master
- />Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON Canada
| | - Marie-Noëlle Rosso
- />Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />INRA, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
- />Polytech’Marseille, UMR1163 Biodiversité et Biotechnologie Fongiques, 163 avenue de Luminy, 13288 Marseille, France
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Metges JP, Lebot MA, Faroux R, Riaud F, Gamelin E, Capitain O, Guérin Meyer V, Leynia P, Douillard JY, Senellart H, Rochard S, Louvigné C, Campion L, Dupuis O, Grollier C, Achour NA, Person B, Raoul JL, Boucher E, Bertrand C, Ramée JF, Guivarch L, Etienne PL, Roussel S, Desclos H, Julien MN, Labarre MI, Klein V, Bessard R, Stampfli C, Royet F, Faycal J, Gouva S, Le Bihan G, Couturier M, Gourlaouen A, Bertholom C, Porneuf M, Jobard E, Peguet E, Grasset D, Bouret JF, Bicheler V, Ulvoas A, Miglianico L, Chouzenoux C, Deguiral P, Derenne L, Martin D, Langlet PM, Bodin C, Rossi V, Barré S, Cojocarasu O, Naveau Ploux C, Vidal AM, Cumin I, Egreteau J, Brouard A, Matysiak Budnik T, Thomaré P, Le Bris Michel AS, Piriou G, Largeau R, Elhannani C, Crespeau E, Suberville F, Bourgeois H, Riche C, Lagadec DD, Marhuenda F, Grudé F. Evaluation in usual practice of the bevacizumab-FOLFIRI combination for the first-line treatment of patients with unresectable metastatic colorectal cancer treated in 2006: focus on resected patients and oncogeriatrics: AVASTIN OUEST cohort of the Observatory of Cancer of the Brittany and Pays de la Loire Areas ( Observatoire dédié au Cancer Bretagne / Pays de la Loire). ONCOLOGIE 2014; 16:267-276. [PMID: 26190928 PMCID: PMC4496868 DOI: 10.1007/s10269-014-2391-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 04/07/2014] [Indexed: 01/02/2023]
Abstract
BACKGROUND In 2006, bevacizumab, a targeted therapy agent was combined with FOLFIRI for the firstline treatment of patients with unresectable metastatic colorectal cancer. METHODS/RESULTS A study on a homogenous series of 111 patients from the Brittany and Pays de la Loire areas who received bevacizumab-FOLFIRI as first-line treatment in 2006 showed the following results: 51 responses, 29 stabilisations, 21 progressions and 10 cases of toxicity prior to assessment. Median overall survival (OS) was 25.1 months and median progression-free survival was 10.2 months. Surgery secondary to treatment tripled median OS which reached 59.2 months in resected patients versus 18.8 months in unresected patients. Comparison of patients aged more or less than 70 years showed no differences in terms of benefits or risks. CONCLUSION Bevacizumab-FOLFIRI could be administered as part of a routine care protocol to elderly patients previously evaluated by a geriatric assessment and validated by a multidisciplinary staff.
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Affiliation(s)
- J. P. Metges
- />CHU Brest Morvan, Brest, France
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | | | - R. Faroux
- />CH La Roche-Sur-Yon, La Roche-sur-Yon, France
| | - F. Riaud
- />CH La Roche-Sur-Yon, La Roche-sur-Yon, France
| | - E. Gamelin
- />ICO Paul Papin, Angers, France
- />Fondateur de l’Observatoire dédié au
cancer, Bretagne Pays de la Loire (ex-OMIT B PL), Rennes, France
| | | | | | | | - J. Y. Douillard
- />ICO René Gauducheau, Nantes, France
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | | | | | | | | | - O. Dupuis
- />Centre Jean Bernard/Clinique Victor-Hugo, Le Mans, France
| | - C. Grollier
- />Centre Jean Bernard/Clinique Victor-Hugo, Le Mans, France
| | | | | | | | | | | | - J. F. Ramée
- />Centre Catherine-de-Sienne, Nantes, France
| | - L. Guivarch
- />Centre Catherine-de-Sienne, Nantes, France
| | - P. L. Etienne
- />Clinique Armoricaine de Radiologie, Saint-Brieuc, France
- />Polyclinique Trégor-Lannion, Lannion, France
| | - S. Roussel
- />Clinique Armoricaine de Radiologie, Saint-Brieuc, France
| | | | | | | | - V. Klein
- />Hôpital Privé Océane/Centre Saint Yves
Vannes, Vannes, France
| | - R. Bessard
- />Hôpital Privé Océane/Centre Saint Yves
Vannes, Vannes, France
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | | | | | | | - S. Gouva
- />CH Landerneau, Landerneau, France
| | | | | | | | | | | | - E. Jobard
- />CH Saint-Brieuc, Saint-Brieuc, France
| | - E. Peguet
- />CH Saint-Brieuc, Saint-Brieuc, France
| | | | | | | | | | | | | | - P. Deguiral
- />Clinique Mutualiste de l’Estuaire, Saint-Nazaire, France
| | - L. Derenne
- />Clinique Mutualiste de l’Estuaire, Saint-Nazaire, France
| | - D. Martin
- />Polyclinique du Maine/Centre Mallet Proux Laval, Laval, France
| | | | - C. Bodin
- />Polyclinique du Maine/Centre Mallet Proux Laval, Laval, France
| | - V. Rossi
- />CH Haut Anjou Château Gontier, Château Gontier,
France
| | - S. Barré
- />CH Haut Anjou Château Gontier, Château Gontier,
France
| | | | | | - A. M. Vidal
- />CH Le Mans, Le Mans, France
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | - I. Cumin
- />CH Sud Lorient Hennebont, Hennebont, France
| | - J. Egreteau
- />CH Sud Lorient Hennebont, Hennebont, France
| | - A. Brouard
- />CH Sud Lorient Hennebont, Hennebont, France
| | | | | | | | | | | | | | - E. Crespeau
- />Polyclinique du Parc Cholet, Cholet, France
| | | | - H. Bourgeois
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | - C. Riche
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | - D. Déniel Lagadec
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | - F. Marhuenda
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
| | - F. Grudé
- />Observatoire dédié au Cancer de l’OMEDIT
Bretagne et de l’OMEDIT Pays de la Loire, Rennes, France
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Karuna N, Zhang L, Walton JH, Couturier M, Oztop MH, Master ER, McCarthy MJ, Jeoh T. The impact of alkali pretreatment and post-pretreatment conditioning on the surface properties of rice straw affecting cellulose accessibility to cellulases. Bioresour Technol 2014; 167:232-40. [PMID: 24983695 DOI: 10.1016/j.biortech.2014.05.122] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/29/2014] [Accepted: 05/31/2014] [Indexed: 05/18/2023]
Abstract
Rice straw was pretreated with sodium hydroxide and subsequently conditioned to reduce the pH to 5-6 by either: (1) extensive water washing or (2) acidification with hydrochloric acid then water washing. Alkali pretreatment improved the enzymatic digestibility of rice straw by increasing the cellulose accessibility to cellulases. However, acidification after pretreatment reversed the gains in cellulose accessibility to cellulases and enzymatic digestibility due to precipitation of solubilized compounds. Surface composition analyses by ToF-SIMS confirmed a reduction in surface lignin by pretreatment and water washing, and suggested that acidification precipitated a chemically modified form of lignin on the surfaces of rice straw. The spin-spin relaxation times (T2) of the samples indicated increased porosity in alkali pretreated rice straw. The acidified pretreated rice straw had reduced amounts of water in the longer T2 proton pools associated with water in the pores of the biomass likely due to back-filling by the precipitated components.
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Affiliation(s)
- Nardrapee Karuna
- Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Ave., Davis, CA 95616, USA
| | - Lu Zhang
- Department of Food Science and Technology, University of California at Davis, One Shields Ave., Davis, CA 95616, USA
| | - Jeffrey H Walton
- University of California at Davis Nuclear Magnetic Resonance Facility, One Shields Ave., Davis, CA 95616, USA
| | - Marie Couturier
- Department of Chemical Engineering & Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada
| | - Mecit H Oztop
- Department of Food Engineering, Middle East Technical University, 06800, Ankara, Turkey
| | - Emma R Master
- Department of Chemical Engineering & Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada
| | - Michael J McCarthy
- Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Ave., Davis, CA 95616, USA; Department of Food Science and Technology, University of California at Davis, One Shields Ave., Davis, CA 95616, USA
| | - Tina Jeoh
- Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Ave., Davis, CA 95616, USA.
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18
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Cossette B, Beauchesne MF, Forget A, Lemière C, Larivée P, Rey É, Couturier M, Rodrigue C, Blais L. Systemic corticosteroids for the treatment of asthma exacerbations during and outside of pregnancy in an acute-care setting. Respir Med 2014; 108:1260-7. [PMID: 25060542 DOI: 10.1016/j.rmed.2014.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/27/2014] [Accepted: 07/01/2014] [Indexed: 11/25/2022]
Abstract
BACKGROUND Asthma exacerbations are common during pregnancy with a prevalence as high as 51.9% among women with severe asthma. OBJECTIVE To compare the treatment of asthma exacerbations in an acute-care setting during and outside of pregnancy. METHODS We formed a cohort of women who sought medical care for an asthma exacerbation at a teaching hospital during or in the year preceding pregnancy, between 1998 and 2008. An exacerbation was composed of one or more medical encounters in an acute-care setting (hospital-based outpatient clinic, emergency department, or during hospitalization). Data were retrieved from medical charts and health administrative databases. We compared the use of systemic corticosteroids (SCSs) during and outside of pregnancy with a Cox proportional hazards model. RESULTS The cohort was formed of 39 women who had 40 exacerbations during and 39 exacerbations outside of pregnancy. Use of SCSs to treat exacerbations was less frequent (adjusted hazard ratio: 0.51; 95% CI: 0.31-0.84) during pregnancy. Moreover, upon the first medical encounter related to the exacerbation, SCSs, when administered, were given less frequently to women when pregnant than when non-pregnant (83% vs. 100%). The SCS prescription was filled at the community pharmacy 65% and 67% of the time when it was prescribed at discharge to women when pregnant than when non-pregnant, respectively. CONCLUSION We observed a reduced and delayed use of SCSs for the treatment of asthma exacerbations in women when pregnant than when non-pregnant, with similar numbers of women in both conditions filling their SCSs prescription in pharmacies.
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Affiliation(s)
- Benoit Cossette
- Faculty of Pharmacy, Université de Montréal, Montréal H3C 3J7, Canada; Pharmacy Department, Centre hospitalier universitaire de Sherbrooke, Sherbrooke J1H 5N4, Canada
| | - Marie-France Beauchesne
- Faculty of Pharmacy, Université de Montréal, Montréal H3C 3J7, Canada; Pharmacy Department, Centre hospitalier universitaire de Sherbrooke, Sherbrooke J1H 5N4, Canada; Centre de recherche Clinique Étienne-Le Bel, Centre hospitalier universitaire de Sherbrooke, Sherbrooke J1H 5N4, Canada; Endowment Chair, AstraZeneca in Respiratory Health, Montréal H3C 3J7, Canada
| | - Amélie Forget
- Faculty of Pharmacy, Université de Montréal, Montréal H3C 3J7, Canada; Research Center, Hôpital du Sacré-Coeur de Montréal, Montréal H4J 1C5, Canada
| | - Catherine Lemière
- Research Center, Hôpital du Sacré-Coeur de Montréal, Montréal H4J 1C5, Canada; Faculty of Medicine, Université de Montréal, Montréal H3C 3J7, Canada
| | - Pierre Larivée
- Centre de recherche Clinique Étienne-Le Bel, Centre hospitalier universitaire de Sherbrooke, Sherbrooke J1H 5N4, Canada; Faculty of Medicine, Université de Sherbrooke, Sherbrooke J1H 5N4, Canada
| | - Évelyne Rey
- Faculty of Medicine, Université de Montréal, Montréal H3C 3J7, Canada; Department of Obstetrics and Gynecology and Research Center, Centre hospitalier universitaire Ste-Justine, Montréal H3T 1C5, Canada
| | - Marie Couturier
- Department of Pharmacology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke J1H 5N4, Canada
| | - Claudie Rodrigue
- Department of Pharmacology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke J1H 5N4, Canada
| | - Lucie Blais
- Faculty of Pharmacy, Université de Montréal, Montréal H3C 3J7, Canada; Centre de recherche Clinique Étienne-Le Bel, Centre hospitalier universitaire de Sherbrooke, Sherbrooke J1H 5N4, Canada; Endowment Chair, AstraZeneca in Respiratory Health, Montréal H3C 3J7, Canada; Research Center, Hôpital du Sacré-Coeur de Montréal, Montréal H4J 1C5, Canada.
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Couturier M, Féliu J, Bozonnet S, Roussel A, Berrin JG. Molecular engineering of fungal GH5 and GH26 beta-(1,4)-mannanases toward improvement of enzyme activity. PLoS One 2013; 8:e79800. [PMID: 24278180 PMCID: PMC3838371 DOI: 10.1371/journal.pone.0079800] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 10/04/2013] [Indexed: 11/18/2022] Open
Abstract
Microbial mannanases are biotechnologically important enzymes since they target the hydrolysis of hemicellulosic polysaccharides of softwood biomass into simple molecules like manno-oligosaccharides and mannose. In this study, we have implemented a strategy of molecular engineering in the yeast Yarrowia lipolytica to improve the specific activity of two fungal endo-mannanases, PaMan5A and PaMan26A, which belong to the glycoside hydrolase (GH) families GH5 and GH26, respectively. Following random mutagenesis and two steps of high-throughput enzymatic screening, we identified several PaMan5A and PaMan26A mutants that displayed improved kinetic constants for the hydrolysis of galactomannan. Examination of the three-dimensional structures of PaMan5A and PaMan26A revealed which of the mutated residues are potentially important for enzyme function. Among them, the PaMan5A-G311S single mutant, which displayed an impressive 8.2-fold increase in kcat /KM due to a significant decrease of KM, is located within the core of the enzyme. The PaMan5A-K139R/Y223H double mutant revealed modification of hydrolysis products probably in relation to an amino-acid substitution located nearby one of the positive subsites. The PaMan26A-P140L/D416G double mutant yielded a 30% increase in kcat /KM compared to the parental enzyme. It displayed a mutation in the linker region (P140L) that may confer more flexibility to the linker and another mutation (D416G) located at the entrance of the catalytic cleft that may promote the entrance of the substrate into the active site. Taken together, these results show that the directed evolution strategy implemented in this study was very pertinent since a straightforward round of random mutagenesis yielded significantly improved variants, in terms of catalytic efiiciency (kcat/KM).
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Affiliation(s)
- Marie Couturier
- INRA, UMR1163, Laboratoire de Biotechnologie des Champignons Filamenteux, Polytech Marseille, Marseille, France
- Aix Marseille Université, Polytech Marseille, Marseille, France
| | - Julia Féliu
- INRA, UMR1163, Laboratoire de Biotechnologie des Champignons Filamenteux, Polytech Marseille, Marseille, France
- Aix Marseille Université, Polytech Marseille, Marseille, France
| | - Sophie Bozonnet
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792, Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
| | - Alain Roussel
- Architecture et Fonction des Macromolécules Biologiques, UMR7257, CNRS, Aix Marseille Université, Marseille, France
| | - Jean-Guy Berrin
- INRA, UMR1163, Laboratoire de Biotechnologie des Champignons Filamenteux, Polytech Marseille, Marseille, France
- Aix Marseille Université, Polytech Marseille, Marseille, France
- * E-mail:
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20
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Couturier M, Lamarthée B, Arbez J, Renauld JC, Bossard C, Malard F, Bonnefoy F, Mohty M, Perruche S, Tiberghien P, Saas P, Gaugler B. IL-22 deficiency in donor T cells attenuates murine acute graft-versus-host disease mortality while sparing the graft-versus-leukemia effect. Leukemia 2013; 27:1527-37. [PMID: 23399894 DOI: 10.1038/leu.2013.39] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 01/20/2013] [Accepted: 02/06/2013] [Indexed: 12/24/2022]
Abstract
Acute graft-versus-host disease (aGVHD) remains a major complication following allogeneic hematopoietic cell transplantation (allo-HCT), limiting the success of this therapy. Many proinflammatory cytokines secreted following the conditioning regimen have been linked to aGVHD initiation. Interleukin-22 (IL-22) is a cytokine related to IL-10 for its structure and is secreted by T helper type 17 (TH17) cells and innate immune cells. Given the paradoxical role of IL-22 in inflammation with both protective or proinflammatory functions, we investigated whether IL-22 could have a role in aGVHD pathophysiology in a mouse allo-HCT model. In this study, we show that IL-22 deficiency in donor T cells can decrease the severity of aGVHD, while limiting systemic and local inflammation in aGVHD target organs. In addition, we found that Foxp3+ regulatory T cells (Treg cells) were increased in recipient mice that received IL-22-deficient T cells, suggesting that Treg were involved in the reduced severity of GVHD. Finally, we found that the graft-versus-leukemia (GVL) effect mediated by donor T cells was preserved in the absence of IL-22. Overall, these data suggest that targeting of IL-22 may represent a valid approach towards decreasing aGVHD severity after allo-HCT while preserving the GVL effect.
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Couturier M, Roussel A, Rosengren A, Leone P, Stålbrand H, Berrin JG. Structural and biochemical analyses of glycoside hydrolase families 5 and 26 β-(1,4)-mannanases from Podospora anserina reveal differences upon manno-oligosaccharide catalysis. J Biol Chem 2013; 288:14624-14635. [PMID: 23558681 DOI: 10.1074/jbc.m113.459438] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The microbial deconstruction of the plant cell wall is a key biological process that is of increasing importance with the development of a sustainable biofuel industry. The glycoside hydrolase families GH5 (PaMan5A) and GH26 (PaMan26A) endo-β-1,4-mannanases from the coprophilic ascomycete Podospora anserina contribute to the enzymatic degradation of lignocellulosic biomass. In this study, P. anserina mannanases were further subjected to detailed comparative analysis of their substrate specificities, active site organization, and transglycosylation capacity. Although PaMan5A displays a classical mode of action, PaMan26A revealed an atypical hydrolysis pattern with the release of mannotetraose and mannose from mannopentaose resulting from a predominant binding mode involving the -4 subsite. The crystal structures of PaMan5A and PaMan26A were solved at 1.4 and 2.85 Å resolution, respectively. Analysis of the PaMan26A structure supported strong interaction with substrate at the -4 subsite mediated by two aromatic residues Trp-244 and Trp-245. The PaMan26A structure appended to its family 35 carbohydrate binding module revealed a short and proline-rich rigid linker that anchored together the catalytic and the binding modules.
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Affiliation(s)
- Marie Couturier
- INRA, UMR1163 BCF, Aix Marseille Université, Polytech Marseille, F-13288 Marseille, France
| | - Alain Roussel
- Architecture et Fonction des Macromolécules Biologiques, Aix Marseille Université, CNRS UMR7257, F-13288 Marseille, France
| | - Anna Rosengren
- Department of Biochemistry and Structural Biology, Lund University, P. O. Box 124, S-221 00, Lund, Sweden
| | - Philippe Leone
- Architecture et Fonction des Macromolécules Biologiques, Aix Marseille Université, CNRS UMR7257, F-13288 Marseille, France
| | - Henrik Stålbrand
- Department of Biochemistry and Structural Biology, Lund University, P. O. Box 124, S-221 00, Lund, Sweden
| | - Jean-Guy Berrin
- INRA, UMR1163 BCF, Aix Marseille Université, Polytech Marseille, F-13288 Marseille, France.
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Couturier M, Nicolas B, Audia S, Nguyen A, Leguy-Seguin V, Bonniaud B, Bonnotte B, Lorcerie B. Les dessous CHICS du méthotrexate. Rev Med Interne 2012. [DOI: 10.1016/j.revmed.2012.10.250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Nicolas B, Audia S, Couturier M, Leguy-Seguin V, Bonnotte B, Lorcerie B. Un PTI atypique : quand les gènes s’en mêlent…. Rev Med Interne 2012. [DOI: 10.1016/j.revmed.2012.10.195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Couturier M, Navarro D, Olivé C, Chevret D, Haon M, Favel A, Lesage-Meessen L, Henrissat B, Coutinho PM, Berrin JG. Post-genomic analyses of fungal lignocellulosic biomass degradation reveal the unexpected potential of the plant pathogen Ustilago maydis. BMC Genomics 2012; 13:57. [PMID: 22300648 PMCID: PMC3298532 DOI: 10.1186/1471-2164-13-57] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 02/02/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Filamentous fungi are potent biomass degraders due to their ability to thrive in ligno(hemi)cellulose-rich environments. During the last decade, fungal genome sequencing initiatives have yielded abundant information on the genes that are putatively involved in lignocellulose degradation. At present, additional experimental studies are essential to provide insights into the fungal secreted enzymatic pools involved in lignocellulose degradation. RESULTS In this study, we performed a wide analysis of 20 filamentous fungi for which genomic data are available to investigate their biomass-hydrolysis potential. A comparison of fungal genomes and secretomes using enzyme activity profiling revealed discrepancies in carbohydrate active enzymes (CAZymes) sets dedicated to plant cell wall. Investigation of the contribution made by each secretome to the saccharification of wheat straw demonstrated that most of them individually supplemented the industrial Trichoderma reesei CL847 enzymatic cocktail. Unexpectedly, the most striking effect was obtained with the phytopathogen Ustilago maydis that improved the release of total sugars by 57% and of glucose by 22%. Proteomic analyses of the best-performing secretomes indicated a specific enzymatic mechanism of U. maydis that is likely to involve oxido-reductases and hemicellulases. CONCLUSION This study provides insight into the lignocellulose-degradation mechanisms by filamentous fungi and allows for the identification of a number of enzymes that are potentially useful to further improve the industrial lignocellulose bioconversion process.
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Silva GGD, Couturier M, Berrin JG, Buléon A, Rouau X. Effects of grinding processes on enzymatic degradation of wheat straw. Bioresour Technol 2012; 103:192-200. [PMID: 22029959 DOI: 10.1016/j.biortech.2011.09.073] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/15/2011] [Accepted: 09/16/2011] [Indexed: 05/05/2023]
Abstract
The effectiveness of wheat straw fine to ultra-fine grindings at pilot scale was studied. The produced powders were characterised by their particle-size distribution (laser diffraction), crystallinity (WAXS) and enzymatic degradability (Trichoderma reesei enzymatic cocktail). A large range of wheat-straw powders was produced: from coarse (median particle size ∼800 μm) to fine particles (∼50 μm) using sieve-based grindings, then ultra-fine particles ∼20 μm by jet milling and ∼10 μm by ball milling. The wheat straw degradability was enhanced by the decrease of particle size until a limit: ∼100 μm, up to 36% total carbohydrate and 40% glucose hydrolysis yields. Ball milling samples overcame this limit up to 46% total carbohydrate and 72% glucose yields as a consequence of cellulose crystallinity reduction (from 22% to 13%). Ball milling appeared to be an effective pretreatment with similar glucose yield and superior carbohydrate yield compared to steam explosion pretreatment.
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Affiliation(s)
- Gabriela Ghizzi D Silva
- INRA, UMR 1208 IATE Agropolymers Engineering and Emerging Technologies, INRA/CIRAD/UM2/SupAgro, 2 place Pierre Viala, F-34060 Montpellier, France
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Barnay JL, Couturier M, Troisgros O, Lothe M, Benaïm C, Casillas JM. Chronic low back pain patient, a candidate for cardiac rehabilitation? Ann Phys Rehabil Med 2011. [DOI: 10.1016/j.rehab.2011.07.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Navarro D, Couturier M, da Silva GGD, Berrin JG, Rouau X, Asther M, Bignon C. Automated assay for screening the enzymatic release of reducing sugars from micronized biomass. Microb Cell Fact 2010; 9:58. [PMID: 20637080 PMCID: PMC2919459 DOI: 10.1186/1475-2859-9-58] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 07/16/2010] [Indexed: 11/10/2022] Open
Abstract
Background To reduce the production cost of bioethanol obtained from fermentation of the sugars provided by degradation of lignocellulosic biomass (i.e., second generation bioethanol), it is necessary to screen for new enzymes endowed with more efficient biomass degrading properties. This demands the set-up of high-throughput screening methods. Several methods have been devised all using microplates in the industrial SBS format. Although this size reduction and standardization has greatly improved the screening process, the published methods comprise one or more manual steps that seriously decrease throughput. Therefore, we worked to devise a screening method devoid of any manual steps. Results We describe a fully automated assay for measuring the amount of reducing sugars released by biomass-degrading enzymes from wheat-straw and spruce. The method comprises two independent and automated steps. The first step is the making of "substrate plates". It consists of filling 96-well microplates with slurry suspensions of micronized substrate which are then stored frozen until use. The second step is an enzymatic activity assay. After thawing, the substrate plates are supplemented by the robot with cell-wall degrading enzymes where necessary, and the whole process from addition of enzymes to quantification of released sugars is autonomously performed by the robot. We describe how critical parameters (amount of substrate, amount of enzyme, incubation duration and temperature) were selected to fit with our specific use. The ability of this automated small-scale assay to discriminate among different enzymatic activities was validated using a set of commercial enzymes. Conclusions Using an automatic microplate sealer solved three main problems generally encountered during the set-up of methods for measuring the sugar-releasing activity of plant cell wall-degrading enzymes: throughput, automation, and evaporation losses. In its present set-up, the robot can autonomously process 120 triplicate wheat-straw samples per day. This throughput can be doubled if the incubation time is reduced from 24 h to 4 h (for initial rates measurements, for instance). This method can potentially be used with any insoluble substrate that is micronizable. A video illustrating the method can be seen at the following URL: http://www.youtube.com/watch?v=NFg6TxjuMWU
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Affiliation(s)
- David Navarro
- Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS et Université d'Aix-Marseille I et II, 163 Avenue de Luminy CP 925, 13288 Marseille Cedex 09, France
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Couturier M, Buccellato M, Costanzo S, Bourhis JM, Shu Y, Nicaise M, Desmadril M, Flaudrops C, Longhi S, Oglesbee M. High affinity binding between Hsp70 and the C-terminal domain of the measles virus nucleoprotein requires an Hsp40 co-chaperone. J Mol Recognit 2010; 23:301-15. [PMID: 19718689 DOI: 10.1002/jmr.982] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The major inducible 70 kDa heat shock protein (hsp70) binds the measles virus (MeV) nucleocapsid with high affinity in an ATP-dependent manner, stimulating viral transcription and genome replication, and profoundly influencing virulence in mouse models of brain infection. Binding is mediated by two hydrophobic motifs (Box-2 and Box-3) located within the C-terminal domain (N(TAIL)) of the nucleocapsid protein, with N(TAIL) being an intrinsically disordered domain. The current work showed that high affinity hsp70 binding to N(TAIL) requires an hsp40 co-chaperone that interacts primarily with the hsp70 nucleotide binding domain (NBD) and displays no significant affinity for N(TAIL). Hsp40 directly enhanced hsp70 ATPase activity in an N(TAIL)-dependent manner, and formation of hsp40-hsp70-N(TAIL) intracellular complexes required the presence of N(TAIL) Box-2 and 3. Results are consistent with the functional interplay between hsp70 nucleotide and substrate binding domains (SBD), where ATP hydrolysis is rate limiting to high affinity binding to client proteins and is enhanced by hsp40. As such, hsp40 is an essential variable in understanding the outcome of MeV-hsp70 interactions.
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Affiliation(s)
- Marie Couturier
- Architecture et Fonction des Macromolécules Biologiques, UMR 6098 CNRS et Universités Aix-Marseille I et II, Campus de Luminy, 13288 Marseille, Cedex 9, France
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Hussein H, Saheb S, Couturier M, Atassi M, Orsoni A, Carrié A, Therond P, Chantepie S, Robillard P, Bruckert E, Chapman M, Kontush A. MS35 SMALL, DENSE HDL3 PARTICLES EXHIBIT DEFECTIVE ANTIOXIDATIVE AND ANTIINFLAMMATORY FUNCTION IN FAMILIAL HYPERCHOLESTEROLEMIA: PARTIAL CORRECTION BY LDL-APHERESIS. ATHEROSCLEROSIS SUPP 2010. [DOI: 10.1016/s1567-5688(10)70536-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Zerrad-Saadi A, Therond P, Couturier M, Chantepie S, Rye K, Chapman M, Kontush A. Abstract: 82 MECHANISMS IMPLICATED IN THE POTENT PROTECTION OF LDL FROM OXIDATIVE STRESS MEDIATED BY SMALL, DENSE HDL3. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70225-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Colombo M, Bourhis JM, Chamontin C, Soriano C, Villet S, Costanzo S, Couturier M, Belle V, Fournel A, Darbon H, Gerlier D, Longhi S. The interaction between the measles virus nucleoprotein and the Interferon Regulator Factor 3 relies on a specific cellular environment. Virol J 2009; 6:59. [PMID: 19445677 PMCID: PMC2686699 DOI: 10.1186/1743-422x-6-59] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Accepted: 05/15/2009] [Indexed: 11/24/2022] Open
Abstract
Background The genome of measles virus consists of a non-segmented single-stranded RNA molecule of negative polarity, which is encapsidated by the viral nucleoprotein (N) within a helical nucleocapsid. The N protein possesses an intrinsically disordered C-terminal domain (aa 401–525, NTAIL) that is exposed at the surface of the viral nucleopcapsid. Thanks to its flexible nature, NTAIL interacts with several viral and cellular partners. Among these latter, the Interferon Regulator Factor 3 (IRF-3) has been reported to interact with N, with the interaction having been mapped to the regulatory domain of IRF-3 and to NTAIL. This interaction was described to lead to the phosphorylation-dependent activation of IRF-3, and to the ensuing activation of the pro-immune cytokine RANTES gene. Results After confirming the reciprocal ability of IRF-3 and N to be co-immunoprecipitated in 293T cells, we thoroughly investigated the NTAIL-IRF-3 interaction using a recombinant, monomeric form of the regulatory domain of IRF-3. Using a large panel of spectroscopic approaches, including circular dichroism, fluorescence spectroscopy, nuclear magnetic resonance and electron paramagnetic resonance spectroscopy, we failed to detect any direct interaction between IRF-3 and either full-length N or NTAIL under conditions where these latter interact with the C-terminal X domain of the viral phosphoprotein. Furthermore, such interaction was neither detected in E. coli nor in a yeast two hybrid assay. Conclusion Altogether, these data support the requirement for a specific cellular environment, such as that provided by 293T human cells, for the NTAIL-IRF-3 interaction to occur. This dependence from a specific cellular context likely reflects the requirement for a human or mammalian cellular co-factor.
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Affiliation(s)
- Matteo Colombo
- Architecture et Fonction des Macromolécules Biologiques, UMR 6098 CNRS et Universités Aix-Marseille I et II, 163 Avenue de Luminy, Case 932, 13288 Marseille Cedex 09, France.
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Baba-Moussa L, Anani L, Scheftel J, Couturier M, Riegel P, Haïkou N, Hounsou F, Monteil H, Sanni A, Prévost G. Virulence factors produced by strains of Staphylococcus aureus isolated from urinary tract infections. J Hosp Infect 2008; 68:32-8. [DOI: 10.1016/j.jhin.2007.10.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Accepted: 10/05/2007] [Indexed: 11/29/2022]
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Kontush A, Therond P, Zerrad A, Couturier M, de Souza J, Vindis C, Negre-Salvayre A, Chantepie S, Salvayre R, Chapman M. PO2-48 PREFERENTIAL ENRICHMENT OF SPHINGOSINE-1-PHOSPHATE AND DEPLETION OF SPHINGOMYELIN IN SMALL DENSE HDL3: RELEVANCE TO ATHEROPROTECTIVE ACTIVITIES. ATHEROSCLEROSIS SUPP 2007. [DOI: 10.1016/s1567-5688(07)71058-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Mahrouf M, Ouslimani N, Peynet J, Djelidi R, Couturier M, Therond P, Legrand A, Beaudeux JL. Metformin reduces angiotensin-mediated intracellular production of reactive oxygen species in endothelial cells through the inhibition of protein kinase C. Biochem Pharmacol 2006; 72:176-83. [PMID: 16730666 DOI: 10.1016/j.bcp.2006.04.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 04/27/2006] [Accepted: 04/27/2006] [Indexed: 11/15/2022]
Abstract
Oxidative stress plays a major role in the pathogenesis and in the onset of macrovascular complications of diabetes. We previously reported that the antihyperglycaemic drug metformin was able to decrease significantly intracellular reactive oxygen species (ROS) production of bovine aortic endothelial cells (BAEC) activated by high levels of glucose and angiotensin II (ANG). The aim of the present study was to investigate whether the antioxidant effect of metformin on BAEC could be mediated through a modulation of protein kinase C (PKC) activity, which plays a key role in the pathophysiology of diabetes. The effects of metformin on intracellular ROS production, PKC translocation and activity were studied on endothelial cells stimulated by PMA (a direct PKC activator), ANG or high levels of glucose as pathophysiological stimuli of endothelial dysfunction in diabetes. We showed that metformin decreased ROS production on PMA-, ANG- and glucose-stimulated BAEC in a similar manner to that obtained by PKC specific inhibitors (calphostin C, chelerythrine) alone. On the other hand, metformin reduced both PKC membrane translocation and kinase activity in ANG-stimulated cells. In PMA-activated cells, metformin reduced membrane PKC activity but we did not observe any alteration of PKC membrane translocation. Finally, in vitro incubation with purified PKC indicated that metformin had no direct effect on PKC activity. Taken together, our results suggest that metformin exerted intracellular antioxidant properties by decreasing ROS production through the inhibition of PKC activity.
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Affiliation(s)
- M Mahrouf
- EA 3617 Stress Oxydant et Atteintes Vasculaires, Département de Biochimie, Faculté de Pharmacie, 4, Avenue de l'Observatoire, F75006 Paris, France
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Mekhloufi J, Bonnefont-Rousselot D, Yous S, Lesieur D, Couturier M, Thérond P, Legrand A, Jore D, Gardès-Albert M. Antioxidant activity of melatonin and a pinoline derivative on linoleate model system. J Pineal Res 2005; 39:27-33. [PMID: 15978054 DOI: 10.1111/j.1600-079x.2005.00208.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study aimed at investigating the in vitro protective effects of GWC22, a novel pinoline derivative [6-ethyl-1-(3-methoxyphenyl)-2-propyl-1,2,3,4-tetrahydro-beta-carboline] chlorhydrate, against radiation-induced oxidation of linoleate initiated by hydroxyl radicals ((*)OH). Using linoleate micelles (10(-2) m) as lipid model, two indexes of peroxidation have been measured, i.e. conjugated dienes and hydroperoxides. Similar determinations were performed with melatonin in order to compare the protective effects of the two compounds. It was observed that, the higher the concentration of GWC22 (or melatonin) (3 x 10(-5) to 10(-4) m), the stronger the antioxidant ability. In these in vitro assays, GWC22 showed a better antioxidant effect than melatonin for a given antioxidant concentration. A reaction scheme has been proposed to explain the inhibitory effect of an antioxidant via the propagating steps of the lipid peroxidation. Indeed, we have suggested that melatonin and GWC22 may compete with the fatty acid to scavenge lipid peroxyl radicals (LOO(*)). We have estimated a lower limit for the LOO(*) rate constant for GWC22 (>/=1.4 x 10(5)/m/s) and for melatonin (>/=2.8 x 10(4)/m/s) assuming that the k-value of the propagating step in linoleate (LOO(*) + linoleate) was 1.4 x 10(3)/m/s. The difference of reactivity between melatonin and GWC22 in this model system is assumed to be related to their relative lipophilicity.
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Affiliation(s)
- J Mekhloufi
- Laboratoire de Chimie Physique UMR 8601-CNRS, Université Paris 5, Paris, France.
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Feki NC, Thérond P, Couturier M, Liméa G, Legrand A, Jouannet P, Auger J. Human sperm lipid content is modified after migration into human cervical mucus. Mol Hum Reprod 2004; 10:137-42. [PMID: 14742699 DOI: 10.1093/molehr/gah018] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effect of the female genital tract on sperm is not well known. To investigate the effect of cervical mucus on the lipid content of human sperm, we co-incubated sperm and mucus samples in vitro such that the sperm were able to swim in and out of the mucus samples. High performance liquid chromatography and UV detection were used to measure the lipid contents of the sperm and cervical mucus before and after migration. The concentrations of cholesterol, vitamin E, sphingomyelin, diacyls and plasmalogens in sperm were all approximately 45% lower after migration in cervical mucus and the cervical mucus was found to be enriched in some of these lipid species after the sperm migration. These results suggest that the cervical mucus selects a subpopulation of sperm with a lower lipid content. However, a concomitant efflux of various lipid classes from the sperm to the cervical mucus cannot be ruled out.
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Affiliation(s)
- N Chakroun Feki
- Service d'Histologie-Embryologie, Biologie de la Reproduction/CECOS, Hôpital Cochin, 123 Bd de Port-Royal, 75014 Paris
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Vitrac H, Courrègelongue M, Couturier M, Collin F, Thérond P, Rémita S, Peretti P, Jore D, Gardès-Albert M. Radiation-induced peroxidation of small unilamellar vesicles of phosphatidylcholine generated by sonication. Can J Physiol Pharmacol 2004; 82:153-60. [PMID: 15052297 DOI: 10.1139/y04-009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study was aimed at determining the peroxidation of model membranes constituted of liposomes of 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPC) submitted to hydroxyl free radicals (generated by γ-radiolysis) attack. Liposomes of PLPC were prepared using the sonication technique, and dynamic light-scattering (DLS) measurements allowed characterization of the liposomal dispersions. Irradiation damages in sonication-generated liposomes were assessed by monitoring several oxidation products, such as conjugated dienes (by means of UV–visible spectrophotometry) and hydroperoxides (using reverse phase high-performance liquid chromatography (HPLC) associated with chemiluminescence detection). It has been shown that three different families of hydroperoxides are formed: the first one (at low radiation doses) results from HO· attack on the linoleyl chain of PLPC, giving phosphatidylcholine hydroperoxides possessing a conjugated dienic structure; the two others (at high radiation doses) are obtained by the secondary HO· attack on the primary hydroperoxide family. The quantification of these products associated with the comparison of their radiation-dose-dependent formation has provided valuable information concerning the mechanisms of their formation. Analysis by HPLC – mass spectrometry has confirmed the presence of hydroperoxides and underlined various other products, like chain-shortened fragments and oxygenated derivatives of polyunsaturated sn-2 fatty acyl chain residues. Structural assignment proposals of some oxidation products have been proposed.Key words: radiolysis, phospholipids, peroxidation, hydroperoxides, liposomes.
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Affiliation(s)
- H Vitrac
- Laboratoire de Chimie Physique, UMR 8601 -- CNRS, Université Paris 5, 45 rue des Saints-Pères, 75270 Paris CEDEX 06, France.
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Picard D, Brown JP, Rosenthall L, Couturier M, Lévesque J, Dumont M, Ste-Marie LG, Tenenhouse A, Dodin S. Ability of peripheral DXA measurement to diagnose osteoporosis as assessed by central DXA measurement. J Clin Densitom 2004; 7:111-8. [PMID: 14742895 DOI: 10.1385/jcd:7:1:111] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2002] [Revised: 04/08/2003] [Accepted: 05/13/2003] [Indexed: 11/11/2022]
Abstract
In order to evaluate the utility of peripheral measurement of bone mineral density (BMD) in the diagnosis of osteoporosis, we measured BMD at the spine and femoral neck with central dual-energy X-ray absorptiometry (DXA), at phalanx with AccuDXA (Schick) as well as proximal and distal forearm with pDXA (Norland) in 835 women ranging in age from 20 to 85 yr. In receiver operating characteristic (ROC) curves, where a positive case was defined as a T-score < or = -2.5 either on spine or femoral neck, the areas under the curve were not significantly different between sites. At a T-score of -2.5 as determined by each peripheral apparatus, sensitivity and specificity were, respectively, 0.39 and 0.95 for phalanx and 0.75 and 0.85 for proximal forearm whereas they were 0.42 and 0.96 for distal forearm. Using optimal absolute BMD cutoff values improved the results. Sensitivity and specificity were, respectively, 0.79 and 0.83 for phalanx at an absolute BMD value of 0.436 and 0.84 and 0.79 for proximal forearm at a value of 0.703, whereas they were 0.90 and 0.75 for distal forearm at a value of 0.208. Combining the two forearm measurements improves the results slightly. At cutoff values of 0.641 and 0.252, respectively for proximal and distal forearms, sensitivity was 0.83 and specificity was 0.84. Therefore, a peripheral measurement of BMD together with a good clinical evaluation of the osteoporosis risk profile of the patient, can be an interesting tool for the diagnosis of osteoporosis in areas where central DXA is not available.
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Affiliation(s)
- D Picard
- Department of Nuclear Medicine, Hôpital Saint-Luc, Université de Montréal, Montreal, Québec, Canada.
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Krakowski I, Theobald S, Balp L, Bonnefoi MP, Chvetzoff G, Collard O, Collin E, Couturier M, Delorme T, Duclos R, Eschalier A, Fergane B, Larue F, Magnet M, Minello C, Navez ML, Richard A, Richard B, Rostaing-Rigattieri S, Rousselot H, Santolaria N, Torloting G, Toussaint S, Vuillemin N, Wagner JP, Fabre N. Summary version of the Standards, Options and Recommendations for the use of analgesia for the treatment of nociceptive pain in adults with cancer (update 2002). Br J Cancer 2003; 89 Suppl 1:S67-72. [PMID: 12915905 PMCID: PMC2753010 DOI: 10.1038/sj.bjc.6601086] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- I Krakowski
- Centre Alexis Vautrin, Vandoeuvre les Nancy, France
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Picard D, Imbach A, Couturier M, Lepage R, Picard M. Familial resemblance of bone mineral density between females 18 years and older and their mothers. Can J Public Health 2001. [PMID: 11702488 DOI: 10.1007/bf03404978] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Potential determinants of bone mass were investigated in a group of 70 young females (mean age 26.6 years), daughters of women studied in premenopause. Nutritional data, leisure physical activity level, lifestyle habits as well as familial similarities were assessed. The daughters' bone mineral density (BMD), measured by dual-energy absorptiometry, was significantly correlated with their body mass index (BMI) (r = 0.22), dietary vitamin D intake (r = 0.19) and their mothers' BMD (r = 0.44). Multiple regression analysis indicated that only the mothers' BMD remained an independent predictor of bone mass. Mother-daughter correlations were also observed for body weight (r = 0.24), height (r = 0.39), BMI (r = 0.29), dietary calcium intake (r = 0.20), and calcium (r = 0.20) or vitamin D (r = 0.25) intakes from dairy products. Hence, these observations support the evidence that mothers' BMD is the strongest predictor of bone mass of young women in their third decade.
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Affiliation(s)
- D Picard
- Department of Nuclear Medicine, Hôpital Saint-Luc and Université de Montréal, Montreal, QC
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41
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Picard D, Imbach A, Couturier M, Lepage R, Picard M. Familial resemblance of bone mineral density between females 18 years and older and their mothers. Can J Public Health 2001; 92:353-8. [PMID: 11702488 PMCID: PMC6979851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/24/2000] [Accepted: 02/21/2001] [Indexed: 02/22/2023]
Abstract
Potential determinants of bone mass were investigated in a group of 70 young females (mean age 26.6 years), daughters of women studied in premenopause. Nutritional data, leisure physical activity level, lifestyle habits as well as familial similarities were assessed. The daughters' bone mineral density (BMD), measured by dual-energy absorptiometry, was significantly correlated with their body mass index (BMI) (r = 0.22), dietary vitamin D intake (r = 0.19) and their mothers' BMD (r = 0.44). Multiple regression analysis indicated that only the mothers' BMD remained an independent predictor of bone mass. Mother-daughter correlations were also observed for body weight (r = 0.24), height (r = 0.39), BMI (r = 0.29), dietary calcium intake (r = 0.20), and calcium (r = 0.20) or vitamin D (r = 0.25) intakes from dairy products. Hence, these observations support the evidence that mothers' BMD is the strongest predictor of bone mass of young women in their third decade.
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Affiliation(s)
- D Picard
- Department of Nuclear Medicine, Hôpital Saint-Luc and Université de Montréal, Montreal, QC
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42
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Abstract
The ccd operon of the F plasmid encodes CcdB, a toxin targeting the essential gyrase of Escherichia coli, and CcdA, the unstable antidote that interacts with CcdB to neutralize its toxicity. Although work from our group and others has established that CcdA and CcdB are required for transcriptional repression of the operon, the underlying mechanism remains unclear. The results presented here indicate that, although CcdA is the DNA-binding element of the CcdA-CcdB complex, the stoichiometry of the two proteins determines whether or not the complex binds to the ccd operator-promoter region. Using electrophoretic mobility shift assays, we show that a (CcdA)2-(CcdB)2 complex binds DNA. The addition of extra CcdB to that protein-DNA complex completely abolishes DNA retardation. Based on these results, we propose a model in which the ratio between CcdA and CcdB regulates the repression state of the ccd operon. When the level of CcdA is superior or equal to that of CcdB, repression results. In contrast, derepression occurs when CcdB is in excess of CcdA. By ensuring an antidote-toxin ratio greater than one, this mechanism could prevent the harmful effect of CcdB in plasmid-containing bacteria.
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Affiliation(s)
- H Afif
- Laboratoire de Génétique des Procaryotes, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12 Rue des Professeurs Jeener et Brachet, 6041 Gosselies, Belgium
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43
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Abstract
The pBHR1 plasmid is a derivative of the small (2.6-kb), mobilizable broad-host-range plasmid pBBR1, which was isolated from the gram-negative bacterium Bordetella bronchiseptica (R. Antoine and C. Locht, Mol. Microbiol. 6:1785-1799, 1992). Plasmid pBBR1 consists of two functional cassettes and presents sequence similarities with the transfer origins of several plasmids and mobilizable transposons from gram-positive bacteria. We show that the Mob protein specifically recognizes a 52-bp sequence which contains, in addition to the transfer origin, the promoter of the mob gene. We demonstrate that this gene is autoregulated. The binding of the Mob protein to the 52-bp sequence could thus allow the formation of a protein-DNA complex with a double function: relaxosome formation and mob gene regulation. We show that the Mob protein is a relaxase, and we located the nic site position in vitro. After sequence alignment, the position of the nic site of pBBR1 corresponds with those of the nick sites of the Bacteroides mobilizable transposon Tn4555 and the streptococcal plasmid pMV158. The oriT of the latter is characteristic of a family of mobilizable plasmids that are found in gram-positive bacteria and that replicate by the rolling-circle mechanism. Plasmid pBBR1 thus appears to be a new member of this group, even though it resides in gram-negative bacteria and does not replicate via a rolling-circle mechanism. In addition, we identified two amino acids of the Mob protein necessary for its activity, and we discuss their involvement in the mobilization mechanism.
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Affiliation(s)
- C Y Szpirer
- Laboratoire de Génétique des Procaryotes, Département de Biologie Moléculaire, Université Libre de Bruxelles, B-6041 Gosselies, Belgium.
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Couturier M, Tucker JL, Andresen BM, Dubé P, Negri JT. Palladium and Raney nickel catalyzed methanolic cleavage of stable borane-amine complexes. Org Lett 2001; 3:465-7. [PMID: 11428040 DOI: 10.1021/ol006969+] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[figure: see text] Palladium and Raney nickel were found to catalyze the methanolysis of borane-amine adducts. Hence, strongly complexed amines can now be liberated by simple treatment with Pd/C or Raney Ni in methanol. The method is applicable to primary, secondary, tertiary, and aromatic amines, and the mildness of the reaction conditions allows preservation of otherwise labile functional groups.
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Affiliation(s)
- M Couturier
- Pfizer Global Research and Development, Eastern Point Road, P.O. Box 8013, Groton, Connecticut 06340-8013, USA.
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45
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Davit-Spraul A, Cosson C, Couturier M, Hadchouel M, Legrand A, Lemonnier F, Therond P. Standard treatment of alpha-tocopherol in Alagille patients with severe cholestasis is insufficient. Pediatr Res 2001; 49:232-6. [PMID: 11158519 DOI: 10.1203/00006450-200102000-00017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Alpha-tocopherol (alpha-T) is the most effective lipid-soluble antioxidant present in cells. We investigated the efficacy of alpha-T supplements for preventing lipid peroxidation in patients with Alagille syndrome, according to the severity of cholestasis. Patients were assigned to two groups on the basis of plasma bilirubin concentration (group I, bilirubin <100 microM; group II, bilirubin >100 microM). alpha-T concentrations were determined in plasma, in isolated lipoproteins, and in red blood cell membranes. In both groups of patients, alpha-T concentrations in plasma were similar to those in control subjects, but the distribution of alpha-T in lipoproteins was affected by the abnormal lipoprotein pattern in these patients. The efficacy of alpha-T was estimated by determining the amount of hydroperoxide produced from phosphatidylcholine and phosphatidylethanolamine (PE) molecular species owing to oxidative stress induced by lipoxygenase treatment. The concentrations of phosphatidylcholine molecular species and its corresponding hydroperoxides were significantly higher in both groups of patients. In group I, alpha-T and PE molecular species concentrations were similar to those in control subjects, but PE hydroperoxide concentrations were higher than those in the control subjects. In group II, alpha-T concentration was significantly lower and the concentrations of some PE molecular species and all PE hydroperoxides were lower than those in the control subjects. In conclusion, erythrocyte membrane alpha-T concentration was significantly lower only in patients with severe jaundice, despite alpha-T supplementation, raising the question as to whether the usual treatment was appropriate in this group.
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Affiliation(s)
- A Davit-Spraul
- INSERM U347, Hôpital Bicêtre, AP-HP, 94276 Le Kremlin-Bicêtre Cedex, France
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46
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Abstract
The evolution of bone mass across menopause as well as the factors related to bone loss were studied in 141 women already assessed 10 years ago while in premenopause. Bone density of the lumbar spine was measured by dual photon absorptiometry. Nutrient intakes, lifestyle habits, data on menopause, and hormone replacement therapy were obtained by questionnaires. Present bone density was related significantly to past and current calcium intake, current vitamin D intake, and leisure physical activity level, as well as bone density measured in premenopause. Average bone loss was related to time elapsed without estrogens, age at menopause and present age, as well as serum levels of osteocalcin and alkaline phosphatase (ALP). Bone loss was inversely related to calcium and vitamin D intakes and to serum 25-OH vitamin D (25OHD) levels. By multiple regression analyses, only bone density in premenopause, time without estrogens, weight, vitamin D intake, and serum ALP levels remained as independent predictors of present bone mass or bone loss. This study emphasizes the importance of building a good bone mass before menopause, of having adequate vitamin D intake, and of beginning estrogen replacement therapy as soon as possible to minimize bone loss in the first years of menopause.
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Affiliation(s)
- D Picard
- Department of Nuclear Medicine, Hôpital Saint-Luc, Université de Montréal, Montreal, Quebec, Canada
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47
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Abstract
It is currently believed that interaction between the relaxosome of a mobilizable plasmid and the transfer machinery of the helper conjugative plasmid is mediated by a TraG family coupling protein. The coupling proteins appear as an essential determinant of mobilization specificity and efficiency. Using a two-hybrid system, we demonstrated for the first time the direct in vivo interaction between the coupling protein of a conjugative plasmid (the TraG protein of RP4) and the relaxase of a mobilizable plasmid (the Mob protein of pBHR1, a derivative of the broad host range plasmid pBBR1). This interaction was confirmed in vitro by an overlay assay and was shown to occur even in the absence of the transfer origin of pBHR1. We showed that, among 11 conjugative plasmids tested, pBHR1 is efficiently mobilized only by plasmids encoding an IncP-type transfer system. We also showed that the RP4 TraG coupling protein is essential for mobilization of a pBBR1 derivative and is the element that allows its mobilization by R388 plasmid (IncW) at a detectable frequency.
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Affiliation(s)
- C Y Szpirer
- Laboratoire de Génétique des Procaryotes, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12, Rue Prof. Jeener et Brachet, B-6041 Gosselies, Belgium.
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Therond P, Abella A, Laurent D, Couturier M, Chalas J, Legrand A, Lindenbaum A. In vitro study of the cytotoxicity of isolated oxidized lipid low-density lipoproteins fractions in human endothelial cells: relationship with the glutathione status and cell morphology. Free Radic Biol Med 2000; 28:585-96. [PMID: 10719240 DOI: 10.1016/s0891-5849(99)00265-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Toxic effects of oxidized lipid compounds contained in oxidized LDL to endothelial cells are involved in the pathogenesis of atherosclerosis. Glutathione (GSH) plays an important role in the redox status of the cell and in the protective effect against oxidant injuries. However, little is known about the respective effect of these different oxidized lipid compounds toward cytotoxicity and GSH status of the cell. In this report, we isolated by high-performance liquid chromatography oxidized lipid compounds from low-density lipoproteins (LDL) oxidized by copper and we examined their effects on cultured endothelial cells. Cytotoxicity and GSH status were determined after incubation of endothelial cells with crude LDL or isolated lipid fractions derived from cholesterol, phospholipids, or cholesteryl esters. Their effects on cell morphology were also assessed. Oxidized lipids coming from cholesteryl esters (hydroperoxides or short-chain polar derivatives) induced a slight but significant GSH depletion without inducing cytotoxicity. The same species coming from phospholipids induced a more pronounced GSH depletion and a cytotoxic effect which is only present for the more polar compounds (short-chain polar derivatives) and corresponding to a total GSH depletion. In contrast, fractions containing oxysterols had a larger cytotoxic effect than their effect on GSH depletion suggesting that their cytotoxic effects are mediated by a GSH-independent pathway. All together, these data suggest that LDL-associated oxidized lipids present in copper-oxidized LDL exert cytotoxicity by an additional or synergistic effect on GSH depletion, but also by another mechanism independent of the redox status of the cell.
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Affiliation(s)
- P Therond
- Inserm U347, Le Kremlin Bicêtre, France
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Hindo J, Hauville C, Rémita S, Thérond P, Couturier M, Jore D, Gardès-Albert M. Evidence of the formation of different hydroperoxides in irradiated gamma-linolenate solutions: effect of micelle formation. Radiat Res 2000; 153:201-7. [PMID: 10629620 DOI: 10.1667/0033-7587(2000)153[0201:eotfod]2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Peroxidation of unconjugated polyunsaturated fatty acids such as linolenic acid proceeds through a free radical chain mechanism and is accompanied by the formation of conjugated dienes such as hydroperoxides. In an investigation of radiation-induced oxidation of aqueous linolenate, we have measured two indexes of peroxidation: (1) conjugated dienes by means of absorption spectroscopy and (2) hydroperoxides by high-pressure liquid chromatography using detection of chemiluminescence. The experimental results indicate a strong effect of the concentration of linolenate on the yields of oxidized products. In addition, this work shows the quantitative production of two kinds of hydroperoxides. The ratio of these hydroperoxides is independent of the radiation dose but is dependent on the linolenate concentration. One hydroperoxide is formed predominantly below the critical micellar concentration (3 mM under our conditions), while the second is observed predominantly when micelles are formed in the aqueous medium. The influence of the composition of the medium on the nature of both hydroperoxides is discussed. [bj163]
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Affiliation(s)
- J Hindo
- Laboratoire de Chimie-Physique, UMR 8601, CNRS, Université Paris V, 45 rue des Saints-Pères, 75270 Paris cedex 06, France
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Chapman M, Chancharme L, Thérond P, Nigon F, Lepage S, Couturier M. Molecular mechanisms of oxidation in small, dense LDL. Atherosclerosis 1999. [DOI: 10.1016/s0021-9150(99)80019-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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