534 results on '"Bourgoin, A."'
Search Results
2. Human Inflammatory Neutrophils Express Genes Encoding Peptidase Inhibitors: Production of Elafin Mediated by NF-κB and CCAAT/Enhancer-Binding Protein β
- Author
-
Patrice E. Poubelle, Isabelle Allaeys, Sylvain G. Bourgoin, and Flavia Ribeiro de Vargas
- Subjects
Neutrophils ,Immunology ,Autoimmunity ,Inflammation ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Immune system ,Downregulation and upregulation ,Osteoarthritis ,Synovial Fluid ,medicine ,Humans ,Immunology and Allergy ,Cells, Cultured ,Ccaat-enhancer-binding proteins ,Tumor Necrosis Factor-alpha ,Arthritis ,CCAAT-Enhancer-Binding Protein-beta ,NF-kappa B ,Granulocyte-Macrophage Colony-Stimulating Factor ,NF-κB ,Molecular biology ,Elafin ,chemistry ,Apoptosis ,Tumor necrosis factor alpha ,Interleukin-4 ,medicine.symptom ,Signal Transduction ,030215 immunology - Abstract
The concept of plasticity of neutrophils is highlighted by studies showing their ability to transdifferentiate into APCs. In this regard, transdifferentiated neutrophils were found at inflammatory sites of autoimmune arthritis (AIA). Exposure of neutrophils to inflammatory stimuli prolongs their survival, thereby favoring the acquisition of pathophysiologically relevant phenotypes and functions. By using microarrays, quantitative RT-PCR, and ELISAs, we showed that long-lived (LL) neutrophils obtained after 48 h of culture in the presence of GM-CSF, TNF, and IL-4 differentially expressed genes related to apoptosis, MHC class II, immune response, and inflammation. The expression of anti-inflammatory genes mainly of peptidase inhibitor families is upregulated in LL neutrophils. Among these, the PI3 gene encoding elafin was the most highly expressed. The de novo production of elafin by LL neutrophils depended on a synergism between GM-CSF and TNF via the activation and cooperativity of C/EBPβ and NF-κB pathways, respectively. Elafin concentrations were higher in synovial fluids (SF) of patients with AIA than in SF of osteoarthritis. SF neutrophils produced more elafin than blood counterparts. These results are discussed with respect to implications of neutrophils in chronic inflammation and the potential influence of elafin in AIA.
- Published
- 2021
- Full Text
- View/download PDF
3. Platelet EVs contain an active proteasome involved in protein processing for antigen presentation via MHC-I molecules
- Author
-
Genevieve Marcoux, Audrée Laroche, Stephan Hasse, Marie Bellio, Maroua Mbarik, Marie Tamagne, Isabelle Allaeys, Anne Zufferey, Tania Lévesque, Johan Rebetz, Annie Karakeussian-Rimbaud, Julie Turgeon, Sylvain G. Bourgoin, Hind Hamzeh-Cognasse, Fabrice Cognasse, Rick Kapur, John W. Semple, Marie-Josée Hébert, France Pirenne, Herman S. Overkleeft, Bogdan I. Florea, Mélanie Dieude, Benoît Vingert, Eric Boilard, and Landsteiner Laboratory
- Subjects
Blood Platelets ,Proteasome Endopeptidase Complex ,Lymphocyte ,Immunology ,Antigen presentation ,Inbred C57BL ,Biochemistry ,Extracellular Vesicles ,Mice ,Immune system ,Antigen ,MHC class I ,medicine ,Animals ,Humans ,Platelet activation ,Antigen Presentation ,biology ,Chemistry ,Histocompatibility Antigens Class I/analysis ,Histocompatibility Antigens Class I ,fungi ,Proteasome Endopeptidase Complex/analysis ,Cell Biology ,Hematology ,Acquired immune system ,Immune complex ,Cell biology ,Blood Platelets/chemistry ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Extracellular Vesicles/chemistry ,biology.protein - Abstract
In addition to their hemostatic role, platelets play a significant role in immunity. Once activated, platelets release extracellular vesicles (EVs) formed by the budding of their cytoplasmic membranes. Because of their heterogeneity, platelet EVs (PEVs) are thought to perform diverse functions. It is unknown, however, whether the proteasome is transferred from platelets to PEVs or whether its function is retained. We hypothesized that functional protein processing and antigen presentation machinery are transferred to PEVs by activated platelets. Using molecular and functional assays, we found that the active 20S proteasome was enriched in PEVs, along with major histocompatibility complex class I (MHC-I) and lymphocyte costimulatory molecules (CD40L and OX40L). Proteasome-containing PEVs were identified in healthy donor blood, but did not increase in platelet concentrates that caused adverse transfusion reactions. They were augmented, however, after immune complex injections in mice. The complete biodistribution of murine PEVs after injection into mice revealed that they principally reached lymphoid organs, such as spleen and lymph nodes, in addition to the bone marrow, and to a lesser extent, liver and lungs. The PEV proteasome processed exogenous ovalbumin (OVA) and loaded its antigenic peptide onto MHC-I molecules, which promoted OVA-specific CD8+ T-lymphocyte proliferation. These results suggest that PEVs contribute to adaptive immunity through cross-presentation of antigens and have privileged access to immune cells through the lymphatic system, a tissue location that is inaccessible to platelets.
- Published
- 2021
4. Ultrasound-assisted one-pot three-component synthesis of new isoxazolines bearing sulfonamides and their evaluation against hematological malignancies
- Author
-
Maxence Bourgoin, Khalid Bougrin, Rachid Benhida, Mohamed Saadi, Anthony Martin, Cécile Favreau, Lahcen El Ammari, Aicha Talha, Guillaume Robert, Patrick Auberger, Institut des Biomolécules Max Mousseron [Pôle Chimie Balard] (IBMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Acoustics and Ultrasonics ,Nitrile ,Hematological Malignancies ,One-pot synthesis ,QC221-246 ,010402 general chemistry ,01 natural sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Nitriles ,Ultrasound ,medicine ,Humans ,Chemical Engineering (miscellaneous) ,Environmental Chemistry ,[CHIM]Chemical Sciences ,Radiology, Nuclear Medicine and imaging ,QD1-999 ,chemistry.chemical_classification ,Radical processes ,Sulfonamides ,Leukemia ,010405 organic chemistry ,Chemistry ,Alkene ,Organic Chemistry ,Acoustics. Sound ,Myeloid leukemia ,Regioselectivity ,Oxides ,Isoxazoles ,medicine.disease ,Combinatorial chemistry ,Cycloaddition ,0104 chemical sciences ,Hematologic Neoplasms ,Special Section: Ultrasound Food Processing ,Sulfonamides-Isoxazolines ,Trichloroisocyanuric acid - Abstract
Highlights • Ultrasound-assisted, one-pot green synthesis of new isoxazolines bearing sulfonamides. • Selective synthesis of isoxazolines using trichloroisocyanuric acid (TCCA) in EtOH-water as solvent. • Good to excellent yields and shorter reaction times under sonication. • Compound 3 h displayed promising cytotoxic activities against K562 and HL-60 cells., In the present study, following a one-pot two-step protocol, we have synthesized novel sulfonamides-isoxazolines hybrids (3a-r) via a highly regioselective 1,3-dipolar cycloaddition. The present methodology capitalized on trichloroisocyanuric acid (TCCA) as a safe and ecological oxidant and chlorinating agent for the in-situ conversion of aldehydes to nitrile oxides in the presence of hydroxylamine hydrochloride, under ultrasound activation. These nitrile oxides could be engaged in 1,3-dipolar cycloaddition reactions with various alkene to afford the targeted sulfonamides-isoxazolines hybrids (3a-r). The latter were assessed for their antineoplastic activity against model leukemia cell lines (Chronic Myeloid Leukemia, K562 and Promyelocytic Leukemia, HL-60).
- Published
- 2021
- Full Text
- View/download PDF
5. Cell Analysis from Dried Blood Spots: New Opportunities in Immunology, Hematology, and Infectious Diseases
- Author
-
Sandrine Roulland, Franck Galland, Noushine Mossadegh-Keller, Pénélope Bourgoin, Thibaut Markarian, Inès Ait Belkacem, Marie Loosveld, Pierre-Emmanuel Morange, Fabrice Malergue, Jean-Marc Busnel, Pierre Michelet, Isabelle Arnoux, Centre d'Immunologie de Marseille - Luminy (CIML), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Beckman Coulter Immunotech, Marseille, France, Hôpital de la Timone [CHU - APHM] (TIMONE), Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research (C2VN), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and DUMENIL, Anita
- Subjects
Erythrocytes ,analysis ,General Chemical Engineering ,[SDV]Life Sciences [q-bio] ,General Physics and Astronomy ,Medicine (miscellaneous) ,Cell Separation ,Antibodies, Viral ,01 natural sciences ,Immunophenotyping ,Leukocytes ,General Materials Science ,Research Articles ,ComputingMilieux_MISCELLANEOUS ,Blood Specimen Collection ,0303 health sciences ,Hematology ,medicine.diagnostic_test ,Chemistry ,General Engineering ,Flow Cytometry ,3. Good health ,Dried blood spot ,[SDV] Life Sciences [q-bio] ,dried blood spots ,Research Article ,medicine.medical_specialty ,Fingerstick ,Science ,Communicable Diseases ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Microbiology ,Flow cytometry ,03 medical and health sciences ,Internal medicine ,medicine ,Humans ,RNA, Messenger ,Cellular compartment ,030304 developmental biology ,Dried Blood Spot Testing ,Diagnostic Tests, Routine ,SARS-CoV-2 ,010401 analytical chemistry ,COVID-19 ,0104 chemical sciences ,Staining ,cells ,Biomarkers - Abstract
Blood cell analysis is a major pillar of biomedical research and healthcare. These analyses are performed in central laboratories. Rapid shipment from collection site to the central laboratories is currently needed because cells and biomarkers degrade rapidly. The dried blood spot from a fingerstick allows the preservation of cellular molecules for months but entire cells are never recovered. Here leucocyte elution is optimized from dried blood spots. Flow cytometry and mRNA expression profiling are used to analyze the recovered cells. 50–70% of the leucocytes that are dried on a polyester solid support via elution after shaking the support with buffer are recovered. While red blood cells lyse upon drying, it is found that the majority of leucocytes are preserved. Leucocytes have an altered structure that is improved by adding fixative in the elution buffer. Leucocytes are permeabilized, allowing an easy staining of all cellular compartments. Common immunophenotyping and mRNAs are preserved. The ability of a new biomarker (CD169) to discriminate between patients with and without Severe Acute Respiratory Syndrome induced by Coronavirus 2 (SARS‐CoV‐2) infections is also preserved. Leucocytes from blood can be dried, shipped, and/or stored for at least 1 month, then recovered for a wide variety of analyses, potentially facilitating biomedical applications worldwide., A new method is described in which blood is dried on a polyester solid support, shipped, and/or stored at room temperature for at least 1 month. Leucocytes are recovered for a wide variety of biomedical analyses. The method has significant implications for resource limited settings and may facilitate patient management worldwide.
- Published
- 2021
- Full Text
- View/download PDF
6. A novel one-step extracellular staining for flow cytometry: Proof-of-concept on sepsis-related biomarkers
- Author
-
Jack Hayman, Pénélope Bourgoin, Fabienne Venet, Guillaume Monneret, Fabrice Malergue, and Thomas Rimmelé
- Subjects
Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Neutrophils ,Immunology ,Gene Expression ,Blood volume ,Monocytes ,Flow cytometry ,Sepsis ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,medicine ,Humans ,Immunology and Allergy ,Aged ,Staining and Labeling ,medicine.diagnostic_test ,biology ,Chemistry ,Receptors, IgG ,HLA-DR Antigens ,Flow Cytometry ,medicine.disease ,Shock, Septic ,Survival Analysis ,Staining ,Red blood cell ,030104 developmental biology ,medicine.anatomical_structure ,Case-Control Studies ,biology.protein ,Female ,Antibody ,Cytometry ,Biomarkers ,030215 immunology - Abstract
Background Flow cytometry is a powerful analytical technique. However, it requires time-consuming, multi-step sample procedure. A new protocol was developed to perform extracellular staining and red blood cell lysis in one step, using dry antibodies. Common markers of white blood cells as well as sepsis biomarkers were tested as a model for modulated antigen expression. Methods Peripheral blood was stained using the reference and the one-step methods. Recruitment and staining of CD3-, CD4-, CD8-, CD14-, and CD15-positive cells were analyzed. Then, protocol modifications were tested for optimization. Finally, the one-step method was evaluated on subjects in septic conditions, by measuring expressions of CD64 and of HLA-DR. Results No statistical differences were observed between methods when comparing the proportions of cells. The procedure was optimized by decreasing blood volume from 100 μL to 5 μL, lysis from 1 mL to 500 μL, and time from 30 to 15 min. In the blood samples from septic subjects, an increase of CD64 on neutrophils and a decrease of HLA-DR on monocytes were observed. Conclusions The one-step method, described here-in, enables an accurate, streamlined flow cytometry sample preparation protocol. The simplified phenotyping procedure reduces training requirements and could help overcome logistic constraints in many flow cytometry applications.
- Published
- 2019
- Full Text
- View/download PDF
7. Phospholipases D1 and D2 regulate cell cycling in primary prostate cancer cells and are differentially associated with the nuclear matrix
- Author
-
Fiona M. Frame, Leanne K. Archer, Amanda R. Noble, Martin G. Rumsby, Karen Hogg, Dawn Coverley, Norman J. Maitland, and Sylvain G. Bourgoin
- Subjects
Fibrillarin ,Chemistry ,Cell growth ,PLD2 ,Cell ,medicine.disease_cause ,Nuclear matrix ,medicine.disease ,Cell biology ,Prostate cancer ,medicine.anatomical_structure ,medicine ,Carcinogenesis ,PI3K/AKT/mTOR pathway - Abstract
Phospholipases D1 and D2 (PLD1/2) have been implicated in tumorigenesis. We previously detected higher expression of PLD in the nuclei of patient-derived prostate cancer (PCa) cells and prostate cancer cell lines. Here we have examined whether PLD1 or PLD2 are associated with the nuclear matrix and influence cell cycling. PLD1/PLD2 were detected by qualitative immunofluorescence in cultured PCa cells and extracted with a standardised protocol to reveal nuclear matrix-associated proteins. The effects of isoform-specific inhibition of PLD1or PLD2 on PCa cell cycle progression were analysed by flow cytometry. PLD2 mainly co-localised with the nucleolar marker fibrillarin in PCa cells. However, even after complete extraction, some PLD2 remained associated with the nuclear matrix. Inhibiting PLD2 effectively reduced PCa cell cycling into and through S phase. In contrast, PLD1 inhibition effects were weaker, and a subpopulation of cycling patient-derived PCa cells was unaffected by PLD1 inhibition. When associated with the nuclear matrix PLD2 could generate phosphatidic acid to regulate nuclear mTOR and control downstream transcriptional events. The association of PLD2 with the nucleolus also implies a role in stress regulation. The cell cycling results highlight the importance of PLD2 inhibition as a novel potential prostate cancer therapeutic mechanism by differential regulation of cell proliferation.
- Published
- 2021
- Full Text
- View/download PDF
8. Arf6 regulates energy metabolism in neutrophils
- Author
-
Chenqi Zhao, Andrew Z. Leong, Jouda Gamara, Fawzi Aoudji, Lynn Davis, Martin Pelletier, Sylvain G. Bourgoin, Yuji Funakoshi, Yasunori Kanaho, Nathalie Pagé, Emmanuelle Rollet-Labelle, and Tsunaki Hongu
- Subjects
0303 health sciences ,Endosome organization ,Chemistry ,Phospholipase D ,Neutrophils ,Phagocytosis ,hemic and immune systems ,Chemotaxis ,Endocytosis ,Biochemistry ,Macrophage chemotaxis ,Cell biology ,Respiratory burst ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Superoxides ,030220 oncology & carcinogenesis ,Physiology (medical) ,Conditional gene knockout ,Animals ,Energy Metabolism ,030304 developmental biology ,Respiratory Burst - Abstract
The small GTPase Arf6 regulates many cellular processes, including cytoskeletal remodeling, receptor endocytosis, and pathogen phagocytosis. Arf6 silencing in neutrophil (PMN)-like cells is well-known to inhibit chemotactic peptide-mediated activation of phospholipase D, the oxidative burst, and β2 integrin-dependent adhesion. In conditional knockout (cKO) mice, the migration to inflammatory sites of Arf6-deficient PMNs was diminished and associated with reduced cell surface expression of β2 integrins. In this study we assessed the impact of Arf6 depletion on the functions and gene expression profile of PMNs isolated from the mouse air pouch. Numerous genes involved in response to oxygen levels, erythrocyte and myeloid differentiation, macrophage chemotaxis, response to chemicals, apoptosis, RNA destabilization, endosome organization, and vesicle transport were differentially expressed in PMNs cKO for Arf6. Lpar6 and Lacc-1 were the most up-regulated and down-regulated genes, respectively. The deletion of Arf6 also decreased Lacc-1 protein level in PMNs, and silencing of Arf6 in THP-1 monocytic cells delayed LPS-mediated Lacc-1 expression. We report that fMLP or zymosan-induced glycolysis and oxygen consumption rate were both decreased in air pouch PMNs but not in bone marrow PMNs of Arf6 cKO mice. Reduced oxygen consumption correlated with a decrease in superoxide and ROS production. Deletion of Arf6 in PMNs also reduced phagocytosis and interfered with apoptosis. The data suggest that Arf6 regulates energy metabolism, which may contribute to impaired phagocytosis, ROS production, and apoptosis in PMN-Arf6 cKO. This study provides new information on the functions and the inflammatory pathways influenced by Arf6 in PMNs.
- Published
- 2021
9. Analysis of Astroglial Secretomic Profile in the Mecp2-Deficient Male Mouse Model of Rett Syndrome
- Author
-
Yann Ehinger, Valerie Matagne, Valérie Cunin, Emilie Borloz, Michel Seve, Sandrine Bourgoin-Voillard, Ana Borges-Correia, Laurent Villard, Jean-Christophe Roux, Marseille medical genetics - Centre de génétique médicale de Marseille (MMG), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratory of Fundamental and Applied Bioenergetics = Laboratoire de bioénergétique fondamentale et appliquée (LBFA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Grenoble Alpes (UGA), PROteomics and METabolomics Platform [Grenoble] (PROMETHEE), and Gall, Valérie
- Subjects
Male ,Proteomics ,congenital, hereditary, and neonatal diseases and abnormalities ,iTRAQ quantitative proteomic approach ,QH301-705.5 ,Methyl-CpG-Binding Protein 2 ,[SDV]Life Sciences [q-bio] ,Nerve Tissue Proteins ,[SDV.GEN] Life Sciences [q-bio]/Genetics ,Article ,neuronal arborization ,Mice ,Rett syndrome ,Animals ,Biology (General) ,QD1-999 ,Mecp2 ,[SDV.GEN]Life Sciences [q-bio]/Genetics ,[SDV.MHEP] Life Sciences [q-bio]/Human health and pathology ,Neurosecretion ,astrocytes ,[SDV] Life Sciences [q-bio] ,Chemistry ,Disease Models, Animal ,secretome ,Gene Expression Regulation ,Gene Deletion ,[SDV.MHEP]Life Sciences [q-bio]/Human health and pathology - Abstract
Mutations in the X-linked MECP2 gene are responsible for Rett syndrome (RTT), a severe neurological disorder. MECP2 is a transcriptional modulator that finely regulates the expression of many genes, specifically in the central nervous system. Several studies have functionally linked the loss of MECP2 in astrocytes to the appearance and progression of the RTT phenotype in a non-cell autonomous manner and mechanisms are still unknown. Here, we used primary astroglial cells from Mecp2-deficient (KO) pups to identify deregulated secreted proteins. Using a differential quantitative proteomic analysis, twenty-nine proteins have been identified and four were confirmed by Western blotting with new samples as significantly deregulated. To further verify the functional relevance of these proteins in RTT, we tested their effects on the dendritic morphology of primary cortical neurons from Mecp2 KO mice that are known to display shorter dendritic processes. Using Sholl analysis, we found that incubation with Lcn2 or Lgals3 for 48 h was able to significantly increase the dendritic arborization of Mecp2 KO neurons. To our knowledge, this study, through secretomic analysis, is the first to identify astroglial secreted proteins involved in the neuronal RTT phenotype in vitro, which could open new therapeutic avenues for the treatment of Rett syndrome.
- Published
- 2021
- Full Text
- View/download PDF
10. Mixing and unmixing induced by active camphor particles
- Author
-
Florence Raynal, Romain Volk, Mickaël Bourgoin, Clément Gouiller, Cécile Cottin-Bizonne, Laurent Maquet, Christophe Ybert, Liquides et interfaces (L&I), Institut Lumière Matière [Villeurbanne] (ILM), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de l'ENS Lyon (Phys-ENS), École normale supérieure - Lyon (ENS Lyon)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE30-0028,TunaMix,Piloter le mélange des suspensions à l'aide particules (ré-)actives à leur environnement.(2016), and École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL)
- Subjects
Materials science ,Field (physics) ,Computational Mechanics ,FOS: Physical sciences ,Condensed Matter - Soft Condensed Matter ,01 natural sciences ,Spectral line ,010305 fluids & plasmas ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,Colloid ,Camphor ,chemistry.chemical_compound ,0103 physical sciences ,[PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] ,010306 general physics ,Mixing (physics) ,Fluid Flow and Transfer Processes ,Marangoni effect ,Fluid Dynamics (physics.flu-dyn) ,Physics - Fluid Dynamics ,3. Good health ,chemistry ,Chemical physics ,Modeling and Simulation ,Compressibility ,Soft Condensed Matter (cond-mat.soft) ,Stationary state - Abstract
In this experimental study, we report on the mixing properties of interfacial colloidal floaters (glass bubbles) by chemical and hydrodynamical currents generated by self-propelled camphor disks swimming at the air-water interface. Despite reaching a statistically stationary state for the glass bubbles distribution, those floaters always remain only partially mixed. This intermediate state results from a competition between (i) the mixing induced by the disordered motion of many camphor swimmers and (ii) the unmixing promoted by the chemical cloud attached to each individual self-propelled disk. Mixing/unmixing is characterized globally using the standard deviation of concentration and spectra, but also more locally by averaging the concentration field around a swimmer. Besides the demixing process, the system develops a "turbulent-like" concentration spectra, with a large-scale region, an inertial regime and a Batchelor region. We show that unmixing is due to the Marangoni flow around the camphor swimmers, and is associated to compressible effects., Comment: 17 pages, 11 figures, to be published in Physical Review Fluids
- Published
- 2021
- Full Text
- View/download PDF
11. Simultaneous determination of species-specific isotopic composition of Hg by gas chromatography coupled to multicollector ICPMS
- Author
-
Epov, Vladimir N., Rodriguez-Gonzalez, Pablo, Sonke, Jeroen E., Tessier, Emmanuel, Amouroux, David, Bourgoin, Laurence Maurice, and Donard, Olivier F.X.
- Subjects
Mercury -- Properties ,Plasma spectroscopy -- Methods ,Mass spectrometry -- Methods ,Gas chromatography -- Methods ,Chemistry - Abstract
This work presents the simultaneous online determination of the isotopic composition of different Hg species in a single sample by the hyphenation of gas chromatography (GC) with multicollector-inductively coupled plasma mass spectrometry (MC-ICPMS). With the use of commercially available instrumentation, precise and accurate species-specific Hg isotope b values (per mil deviation of the Hg isotope ratio in the sample relative to a reference standard) have been obtained online from consecutive GC transient signals. The use of isothermal temperature programs to extend the elution of the Hg species, the proper selection of the peak integration window, as well as the preconcentration of real samples are critical to provide optimal counting statistics. Also, isotope ratio drift during transient signal elution was overcome by introducing a mixed Hg(II) and MeHg standard bracketing scheme and expressing all results using the b-notation relative to SRM NIST-3133. Using the proposed methodology, we have obtained an external 2SD precision of 0.56 %o for [[delta].sup.202]Hg that is more than 10 times smaller than the overall Hg stable isotope variation thus far observed in terrestrial samples. The measurement of species-specific Hg isotopic composition relative to SRM NIST-3133 has been validated versus two other analytical techniques, i.e., conventional nebulization (CN) of Hg(II) solution and cold vapor (CV) generation of [Hg.sup.0] vapor. A good agreement between the species-specific [delta] values obtained by the different techniques has been obtained in secondary fractionated reference standard (UM-Almadtn) and environmental matrixes, i.e., BCR-CRM 464 (tuna fish) and IAEA-085 (human hair). The results show mass-dependent and mass-independent fractionation in environmental samples, i.e., mass-independent fractionation of odd isotopes [sup.199]Hg and [sup.201]Hg in tuna fish was observed. This methodology provides new possibilities for the future study of species-specific stable isotope geochemistry of Hg and other trace metals.
- Published
- 2008
12. Exploration and Modulation of Antibody Fragment Biophysical Properties by Replacing the Framework Region Sequences
- Author
-
Thomas Cnudde, Marie-Noëlle Mévélec, Nicolas Aubrey, Corinne Henriquet, Martine Pugnière, Zineb Lakhrif, Matthieu O. Juste, Isabella Gizzi Jiacomini, Anne di Tommaso, Fanny Boursin, Isabelle Dimier-Poisson, Justine Bourgoin, Catherine Horiot, Infectiologie et Santé Publique (UMR ISP), Université de Tours (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de Recherche en Cancérologie de Montpellier (IRCM - U1194 Inserm - UM), CRLCC Val d'Aurelle - Paul Lamarque-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Institut du Cancer de Montpellier (ICM), Laboratorio de Imunoquimica, Departamento de Patologia Basica, Universidade Federal do Paraná (UFPR), ANR-10-LABX-0053,MAbImprove,Optimization of therapeutic monoclonal antibodies development Better antibodies, better developed AND better used(2010), Chanteloup, Nathalie Katy, Laboratoires d'excellence - Optimization of therapeutic monoclonal antibodies development Better antibodies, better developed AND better used - - MAbImprove2010 - ANR-10-LABX-0053 - LABX - VALID, and Université de Tours-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
- Subjects
lcsh:Immunologic diseases. Allergy ,0301 basic medicine ,[SDV.IMM] Life Sciences [q-bio]/Immunology ,engineering ,[SDV]Life Sciences [q-bio] ,Immunology ,stabilities ,Article ,03 medical and health sciences ,0302 clinical medicine ,Fragment (logic) ,Drug Discovery ,Immunology and Allergy ,Molecule ,Framework region ,single-chain Fragment variable (scFv) ,chemistry.chemical_classification ,Protein L (PpL) ,biology ,Chemistry ,Prokaryote ,biology.organism_classification ,3. Good health ,Amino acid ,[SDV] Life Sciences [q-bio] ,framework regions ,030104 developmental biology ,030220 oncology & carcinogenesis ,Yield (chemistry) ,biology.protein ,Biophysics ,[SDV.IMM]Life Sciences [q-bio]/Immunology ,production ,Antibody ,lcsh:RC581-607 ,Relevant information - Abstract
In order to increase the successful development of recombinant antibodies and fragments, it seems fundamental to enhance their expression and/or biophysical properties, such as the thermal, chemical, and pH stabilities. In this study, we employed a method bases on replacing the antibody framework region sequences, in order to promote more particularly single-chain Fragment variable (scFv) product quality. We provide evidence that mutations of the VH- C-C&prime, loop might significantly improve the prokaryote production of well-folded and functional fragments with a production yield multiplied by 27 times. Additional mutations are accountable for an increase in the thermal (+19.6 °, C) and chemical (+1.9 M) stabilities have also been identified. Furthermore, the hereby-produced fragments have shown to remain stable at a pH of 2.0, which avoids molecule functional and structural impairments during the purification process. Lastly, this study provides relevant information to the understanding of the relationship between the antibodies amino acid sequences and their respective biophysical properties.
- Published
- 2020
- Full Text
- View/download PDF
13. Predictive factors of mortality in patients treated with tocilizumab for acute respiratory distress syndrome related to coronavirus disease 2019 (COVID-19)
- Author
-
Timothée Klopfenstein, Remy Contreras, Marie Bossert, Aline Charpentier, Vincent Gendrin, Anne Lohse, Isabelle Mazurier, Pierre Yves Royer, Charlotte Bourgoin, Julio Badie, Souheil Zayet, Ana Maria Bozgan, Jean Charles Balblanc, and Thierry Conrozier
- Subjects
0301 basic medicine ,Male ,ARDS ,predictive factors ,Fibrinogen ,Gastroenterology ,chemistry.chemical_compound ,Platelet ,Aged, 80 and over ,Respiratory Distress Syndrome ,biology ,Prognosis ,Anti-Bacterial Agents ,Infectious Diseases ,C-Reactive Protein ,Treatment Outcome ,Female ,Coronavirus Infections ,medicine.drug ,Hydroxychloroquine ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,030106 microbiology ,Immunology ,Pneumonia, Viral ,Antibodies, Monoclonal, Humanized ,Microbiology ,Article ,Fibrin Fibrinogen Degradation Products ,03 medical and health sciences ,tocilizumab ,Betacoronavirus ,Tocilizumab ,Internal medicine ,Lymphopenia ,medicine ,Humans ,Aspartate Aminotransferases ,Pandemics ,Survival analysis ,Aged ,Retrospective Studies ,SARS-CoV-2 ,COVID-19 ,biomarkers ,Anticoagulants ,Retrospective cohort study ,acute respiratory distress syndrome ,medicine.disease ,Survival Analysis ,Thrombocytopenia ,Ferritin ,030104 developmental biology ,chemistry ,biology.protein ,Tomography, X-Ray Computed - Abstract
COVID-19 patients (n = 34) suffering from ARDS were treated with tocilizumab (TCZ). Outcome was classified in two groups: "Death" and "Recovery". Predictive factors of mortality were studied. Mean age was 75.3, mean oxygen (O2) requirements 10.4 l/min. At baseline, all patients had multiple biological abnormalities (lymphopenia, increased CRP, ferritin, fibrinogen, D-dimer and liver enzymes). 24 patients (70.5%) recovered after TCZ therapy and 10 died (29.5%). Deceased subjects differed from patients in whom treatment was effective with regard to more pronounced lymphopenia (0.6 vs 1.0 G/l; p = 0.037), lower platelet number (156 vs 314 G/l; p = 0.0001), lower fibrinogen serum level (0.6 vs 1.0 G/l; p = 0.03), higher aspartate-amino-transferase (108 vs 57 UI/l; p = 0.05) and greater O2 requirements (11 vs 8 l/min; p = 0.003).
- Published
- 2020
14. Corrigendum to 'Arf6 regulates energy metabolism in neutrophils' [Free Radic Biol Med. 172 (2021) 550–561]
- Author
-
Tsunaki Hongu, Chenqi Zhao, Fawzi Aoudji, Emmanuelle Rollet-Labelle, Yasunori Kanaho, Martin Pelletier, Yuji Funakoshi, Sylvain G. Bourgoin, Nathalie Pagé, Andrew Z. Leong, Lynn Davis, and Jouda Gamara
- Subjects
Chemistry ,Physiology (medical) ,Energy metabolism ,Biochemistry ,Cell biology - Published
- 2022
- Full Text
- View/download PDF
15. Current trends in protein acetylation analysis
- Author
-
Jean-François Poisson, Michel Seve, Issa Diallo, Frédéric Minassian, Sandrine Bourgoin-Voillard, Sylvie Michelland, Valérie Cunin, Laboratory of Fundamental and Applied Bioenergetics = Laboratoire de bioénergétique fondamentale et appliquée (LBFA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Centre Hospitalier Universitaire [Grenoble] (CHU)
- Subjects
Proteomics ,0301 basic medicine ,endocrine system ,Proteome ,030102 biochemistry & molecular biology ,Chemistry ,[SDV]Life Sciences [q-bio] ,Acetylation ,Biochemistry ,Mass Spectrometry ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,(N-ter/K-/O-)acetylation ,acetylomics ,Protein Acetylation ,Current (fluid) ,Protein Processing, Post-Translational ,Molecular Biology - Abstract
International audience; Acetylation is a widely occurring post-translational modification (PTM) of proteins that plays a crucial role in many cellular physiological and pathological processes. Over the last decade, acetylation analyses required the development of multiple methods to target individual acetylated proteins, as well as to cover a broader description of acetylated proteins that comprise the acetylome. Areas covered: This review discusses the different types of acetylation (N-ter/K-/O-acetylation) and then describes some major strategies that have been reported in the literature to detect, enrich, identify and quantify protein acetylation. The review highlights the advantages and limitations of these strategies, to guide researchers in designing their experimental investigations and analysis of protein acetylation. Finally, this review highlights the main applications of acetylomics (proteomics based on mass spectrometry) for understanding physiological and pathological conditions. Expert opinion: Recent advances in acetylomics have enhanced knowledge of the biological and pathological roles of protein acetylation and the acetylome. Besides, radiolabeling and western blotting remain also techniques-of-choice for targeted protein acetylation. Future challenges in acetylomics to analyze the N-ter and K-acetylome will most likely require enrichment/fractionation, MS instrumentation and bioinformatics. Challenges also remain to identify the potential biological roles of O-acetylation and cross-talk with other PTMs.
- Published
- 2018
- Full Text
- View/download PDF
16. Recent Advances in Molecular Electronics Based on Carbon Nanotubes
- Author
-
Jean-Philippe Bourgoin, Stéphane Campidelli, Pascale Chenevier, Vincent Derycke, Arianna Filoramo, and Marcelo F. Goffman
- Subjects
Carbon nanotubes ,Cntfet ,Functionalization ,Neuromorphic computing architectures ,Self-assembly ,Chemistry ,QD1-999 - Abstract
Carbon nanotubes (CNTs) have exceptional physical properties that make them one of the most promising building blocks for future nanotechnologies. They may in particular play an important role in the development of innovative electronic devices in the fields of flexible electronics, ultra-high sensitivity sensors, high frequency electronics, opto-electronics, energy sources and nano-electromechanical systems (NEMS). Proofs of concept of several high performance devices already exist, usually at the single device level, but there remain many serious scientific issues to be solved before the viability of such routes can be evaluated. In particular, the main concern regards the controlled synthesis and positioning of nanotubes. In our opinion, truly innovative use of these nano-objects will come from: i) the combination of some of their complementary physical properties, such as combining their electrical and mechanical properties, ii) the combination of their properties with additional benefits coming from other molecules grafted on the nanotubes, and iii) the use of chemically- or bio-directed self-assembly processes to allow the efficient combination of several devices into functional arrays or circuits. In this article, we outline the main issues concerning the development of carbon nanotubes based electronics applications and review our recent results in the field.
- Published
- 2010
- Full Text
- View/download PDF
17. Phospholipase A1 Member A Activates Fibroblast-like Synoviocytes through the Autotaxin-Lysophosphatidic Acid Receptor Axis
- Author
-
Paul R. Fortin, Lynn Davis, Eric Boilard, Chenqi Zhao, Stephan Hasse, Myriam Vaillancourt, Sylvain G. Bourgoin, Yang Zhao, John A. Di Battista, and Patrice E. Poubelle
- Subjects
Male ,autotaxin ,Gout ,Arthritis ,chemokines ,lyso-phosphatidylserine ,chemistry.chemical_compound ,Synovial Fluid ,Lysophosphatidic acid ,Lupus Erythematosus, Systemic ,Biology (General) ,Receptors, Lysophosphatidic Acid ,Receptor ,Spectroscopy ,General Medicine ,Receptor antagonist ,Synoviocytes ,Computer Science Applications ,Chemistry ,lyso-phospholipid ,phosphatidylserine-specific phospholipase A1 ,lysophosphatidic acid ,inflammation ,arthritis ,Lysophosphatidylserine ,Rheumatoid arthritis ,Female ,Autotaxin ,QH301-705.5 ,medicine.drug_class ,Article ,Catalysis ,Inorganic Chemistry ,Phospholipase A1 ,medicine ,Humans ,Physical and Theoretical Chemistry ,QD1-999 ,Molecular Biology ,Phosphoric Diester Hydrolases ,business.industry ,Organic Chemistry ,Fibroblasts ,medicine.disease ,Phospholipases A1 ,chemistry ,Case-Control Studies ,Cancer research ,business - Abstract
Lysophosphatidylserine (lysoPS) is known to regulate immune cell functions. Phospholipase A1 member A (PLA1A) can generate this bioactive lipid through hydrolysis of sn-1 fatty acids on phosphatidylserine (PS). PLA1A has been associated with cancer metastasis, asthma, as well as acute coronary syndrome. However, the functions of PLA1A in the development of systemic autoimmune rheumatic diseases remain elusive. To investigate the possible implication of PLA1A during rheumatic diseases, we monitored PLA1A in synovial fluids from patients with rheumatoid arthritis and plasma of early-diagnosed arthritis (EA) patients and clinically stable systemic lupus erythematosus (SLE) patients. We used human primary fibroblast-like synoviocytes (FLSs) to evaluate the PLA1A-induced biological responses. Our results highlighted that the plasma concentrations of PLA1A in EA and SLE patients were elevated compared to healthy donors. High concentrations of PLA1A were also detected in synovial fluids from rheumatoid arthritis patients compared to those from osteoarthritis (OA) and gout patients. The origin of PLA1A in FLSs and the arthritic joints remained unknown, as healthy human primary FLSs does not express the PLA1A transcript. Besides, the addition of recombinant PLA1A stimulated cultured human primary FLSs to secrete IL-8. Preincubation with heparin, autotaxin (ATX) inhibitor HA130 or lysophosphatidic acid (LPA) receptor antagonist Ki16425 reduced PLA1A-induced-secretion of IL-8. Our data suggested that FLS-associated PLA1A cleaves membrane-exposed PS into lysoPS, which is subsequently converted to LPA by ATX. Since primary FLSs do not express any lysoPS receptors, the data suggested PLA1A-mediated pro-inflammatory responses through the ATX-LPA receptor signaling axis.
- Published
- 2021
- Full Text
- View/download PDF
18. Activation of phospholipase D by bradykinin and sphingosine 1-phosphate in A549 human lung adenocarcinoma cells via different GTP-binding proteins and protein kinase C delta signaling pathways
- Author
-
Meacci, Elisabetta, Nuti, Francesca, Catarzi, Serena, Vasta, Valeria, Donati, Chiara, Bourgoin, Sylvain, Bruni, Paola, Moss, Joel, and Vaughan, Martha
- Subjects
Enzyme activation -- Physiological aspects ,Phospholipases -- Physiological aspects ,Adenocarcinoma -- Physiological aspects ,Cellular signal transduction -- Physiological aspects ,Biological sciences ,Chemistry - Abstract
Results indicate that the effects of agonists bradykinin and sphingosine 1-phosphate on phospholipase D may be mediated by pertussis toxin-insensitive and -sensitive pathways, respectively. In A549 cells sphingosine 1-phosphate activates the enzyme via RhoA and PKCdelta and bradykinin activates phospholipase D1 via a PKCdelta-dependent pathway.
- Published
- 2003
19. Ceramide inhibition of mammalian phospholipase D1 and D2 activities is antagonized by phosphatidylinositol 4,5-bisphosphate
- Author
-
Singh, Indrapal N., Stromberg, Lana M., Bourgoin, Sylvain G., Sciorra, Vicki A., Morris, Andrew J., and Brindley, David N.
- Subjects
Biochemistry -- Research ,Phospholipases -- Physiological aspects ,Sphingolipids -- Physiological aspects ,Phosphatidylinositol -- Physiological aspects ,Cells -- Analysis ,Biological sciences ,Chemistry - Abstract
Research has been conducted on the ceramides which inhibit phospholipase D activity in mammalian cells. The inhibition of phospholipase D1 and D2 by these ceramides and the interaction of the ceramides with phosphatidylinositol 4,5-bisphosphate have been investigated and reported.
- Published
- 2001
20. In vitro, in vivo and ex vivo demonstration of the antitumoral role of hypocretin-1/orexin-A and almorexant in pancreatic ductal adenocarcinoma
- Author
-
Anne Couvelard, Alain Couvineau, Daniela Speisky, Thierry Voisin, Valérie Paradis, Pierre Bourgoin, Valérie Gratio, Pierre Bedossa, Alain Sauvanet, Jérôme Cros, Philippe Ruszniewski, Stéphanie Dayot, and Vinciane Rebours
- Subjects
0301 basic medicine ,patient-derived xenograft ,endocrine system diseases ,pancreatic cancer ,03 medical and health sciences ,Orexin-A ,0302 clinical medicine ,GPCR ,In vivo ,Pancreatic cancer ,mental disorders ,medicine ,orexin receptor ,Chemistry ,Cell growth ,apoptosis ,medicine.disease ,Orexin receptor ,3. Good health ,030104 developmental biology ,Oncology ,nervous system ,Apoptosis ,030220 oncology & carcinogenesis ,Cancer research ,Almorexant ,Ex vivo ,psychological phenomena and processes ,medicine.drug ,Research Paper - Abstract
Pancreatic ductal adenocarcinoma (PDAC) is still the poorest prognostic tumor of the digestive system. We investigated the antitumoral role of orexin-A and almorexant in PDAC. We analyzed the orexin receptor type 1 (OX1R) expression by immunohistochemistry in human normal pancreas, PDAC and its precursor dysplastic intraepithelial lesions. We used PDAC-derived cell lines and fresh tissue slices to study the apoptotic role of hypocretin-1/orexin-A and almorexant in vitro and ex vivo. We analyzed in vivo the hypocretin-1/orexin-A and almorexant effect on tumor growth in mice xenografted with PDAC cell lines expressing, or not, OX1R. Ninety-six percent of PDAC expressed OX1R, while adjacent normal exocrine pancreas did not. OX1R was expressed in pre-cancerous lesions. In vitro, under hypocretin-1/orexin-A and almorexant, the OX1R-positive AsPC-1 cells underwent apoptosis, abolished by the tyrosine phosphatase SHP2 inhibitor, NSC-87877, whereas the OX1R-negative HPAF-II cell line did not. These effects were mediated by phosphorylation of OX1R and recruitment of SHP2. Ex vivo, caspase-3 positive tumor cells were significantly higher in fresh tumour slices treated 48h with hypocretin-1/orexin-A, as compared to control, whereas cellular proliferation, assessed by Ki-67 index, was not modified. In vivo, when AsPC-1 cells or patient-derived cells were xenografted in nude mice, hypocretin-1/orexin-A or almorexant, administrated both starting the day of cell line inoculation or after tumoral development, strongly slowed tumor growth. Hypocretin-1/orexin-A and almorexant induce, through OX1R, the inhibition of PDAC cellular growth by apoptosis. Hypocretins/orexins and almorexant might be powerful candidates for the treatment of PDAC.
- Published
- 2018
21. Low-molecular-weight color pI markers to monitor on-line the peptide focusing process in OFFGEL fractionation
- Author
-
Sandrine Bourgoin-Voillard, Pascal Bertolino, Valérie Cunin, Michel Seve, Sylvie Michelland, Axel Tollance, and Karel Šlais
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,Chromatography ,Resolution (mass spectrometry) ,Chemistry ,Isoelectric focusing ,Clinical Biochemistry ,Peptide ,Fractionation ,Mass spectrometry ,Biochemistry ,High-performance liquid chromatography ,Analytical Chemistry ,03 medical and health sciences ,030104 developmental biology ,Proteome ,Immobilized pH gradient - Abstract
High-throughput mass spectrometry-based proteomic analysis requires peptide fractionation to simplify complex biological samples and increase proteome coverage. OFFGEL fractionation technology became a common method to separate peptides or proteins using isoelectric focusing in an immobilized pH gradient. However, the OFFGEL focusing process may be further optimized and controlled in terms of separation time and pI resolution. Here we evaluated OFFGEL technology to separate peptides from different samples in the presence of low-molecular-weight (LMW) color pI markers to visualize the focusing process. LMW color pI markers covering a large pH range were added to the peptide mixture before OFFGEL fractionation using a 24-wells device encompassing the pH range 3-10. We also explored the impact of LMW color pI markers on peptide fractionation labeled previously for iTRAQ. Then, fractionated peptides were separated by RP_HPLC prior to MS analysis using MALDI-TOF/TOF mass spectrometry in MS and MS/MS modes. Here we report the performance of the peptide focusing process in the presence of LMW color pI markers as on-line trackers during the OFFGEL process and the possibility to use them as pI controls for peptide focusing. This method improves the workflow for peptide fractionation in a bottom-up proteomic approach with or without iTRAQ labeling.
- Published
- 2017
- Full Text
- View/download PDF
22. Gauthierite, KPb[(UO2)7 O5 (OH)7]· 8H2 O, a new uranyl-oxide hydroxy-hydrate mineral from Shinkolobwe with a novel uranyl-anion sheet-topology
- Author
-
Jiří Čejka, Peter C. Burns, Travis A. Olds, Jakub Plášil, Vincent Bourgoin, Anthony R. Kampf, Jean-Claude Boulliard, and Radek Škoda
- Subjects
Chemistry ,05 social sciences ,Electron microprobe ,Crystal structure ,010502 geochemistry & geophysics ,Uranyl ,Topology ,01 natural sciences ,Crystallography ,chemistry.chemical_compound ,Geochemistry and Petrology ,0502 economics and business ,X-ray crystallography ,Pleochroism ,050211 marketing ,Mohs scale of mineral hardness ,Hydrate ,0105 earth and related environmental sciences ,Monoclinic crystal system - Abstract
Gauthierite, KPb[(UO2)7O5(OH)7]·8H2O, is a new uranyl-oxide hydroxy-hydrate mineral from the Shinkolobwe Mine, Democratic Republic of Congo, Africa. It occurs on a matrix of uraninite-bearing quartz gangue associated with soddyite and a minor metazeunerite–metatorbernite series mineral. It is a product of oxidation–hydration weathering of uraninite. Gauthierite is monoclinic, P 21/ c , with a = 29.844(2) A, b = 14.5368(8) A, c = 14.0406(7) A, β = 103.708(6)°, V = 5917.8(6) A3 and Z = 8. Prismatic crystals have pronounced lengthwise striations and reach about 1 mm in length. Gauthierite is yellowish orange with a light orange streak and vitreous lustre. The Mohs hardness is ~3 to 4. It is brittle with an uneven fracture and perfect cleavage on {0 1 0}. The calculated density based on the empirical formula is 5.437 g/cm3. Optically, gauthierite is biaxial (−), with α = 1.780(5), β = 1.815(5), γ = 1.825(5) (white light), 2V meas. = 58(1)°; dispersion is extreme ( r ≫ v ). The optical orientation is X = b , Y ≈ a *, Z ≈ c (or X = b , Y ^ a = 14° in obtuse β); it is pleochroic with X very pale yellow, Y and Z orange-yellow; X ≪ Y ≈ Z . Electron microprobe analyses (average of 9) provided: K2O 1.29, PbO 7.17, UO3 82.10, H2O 8.78 (structure), total 99.34 wt.%. The empirical formula (based on 34 O a.p.f.u. ) is: K0.67Pb0.78U7O34H23.77. The ideal formula is KPb[(UO2)7O5(OH)7](H2O)8, which requires K2O 1.90, PbO 9.00, UO3 80.74, H2O 8.35, total 100 wt.%. Raman and infrared spectral data confirm the presence of UO22+, OH− and molecular H2O. The eight strongest powder X-ray diffraction lines are [ d obs in A ( hkl ) I rel]: 7.28 (020,400) 49, 3.566 (040, −802, −204) 67, 3.192 (622, −224) 100, 2.541 (−842, −244) 18, 2.043 (406) 14, 2.001 (662, −264, 14·2·0) 23, 1.962 (426, −146) 14, and 1.783 (12·0·4, −10·4·6) 17. The crystal structure of gauthierite ( R = 0.0567 for 6997 reflections with [ I > 3σ( I )]) contains uranyl-(hydroxo)-oxide sheets with a novel topology that is similar to that of vandendriesscheite, but with a unique chain sequence UDPDPDUPUP , P4(UD)6. Adjacent sheets are linked through K+ and Pb2+ cations (the lone 6s2 pair on Pb atoms is stereoactive).
- Published
- 2017
- Full Text
- View/download PDF
23. Assessment of Arf6 Deletion in PLB-985 Differentiated in Neutrophil-Like Cells and in Mouse Neutrophils: Impact on Adhesion and Migration
- Author
-
Emmanuelle Rollet-Labelle, Jouda Gamara, Fawzi Aoudjit, Sylvain G. Bourgoin, Tsunaki Hongu, Yasunori Kanaho, Lynn Davis, and Yuji Funakoshi
- Subjects
0301 basic medicine ,Integrin beta Chains ,Article Subject ,Neutrophils ,Immunology ,Integrin ,Blotting, Western ,Genetic Vectors ,Macrophage-1 Antigen ,Apoptosis ,CD11a ,Cell Line ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Conditional gene knockout ,Pathology ,RB1-214 ,Animals ,Humans ,RNA, Small Interfering ,Cells, Cultured ,Mice, Knockout ,Extracellular Matrix Proteins ,biology ,Chemistry ,ADP-Ribosylation Factors ,Reverse Transcriptase Polymerase Chain Reaction ,Cell migration ,Chemotaxis ,hemic and immune systems ,Cell Biology ,Adhesion ,Flow Cytometry ,Lymphocyte Function-Associated Antigen-1 ,Cell biology ,Blood Cell Count ,Fibronectin ,030104 developmental biology ,Integrin alpha M ,ADP-Ribosylation Factor 6 ,biology.protein ,030215 immunology ,Research Article - Abstract
Chemoattractant sensing, adhesiveness, and migration are critical events underlying the recruitment of neutrophils (PMNs) to sites of inflammation or infection. Defects in leukocyte adhesion or migration result in immunodeficiency disorders characterized by recurrent infections. In this study, we evaluated the role of Arf6 on PMN adhesion in vitro and on migration to inflammatory sites using PMN-Arf6 conditional knockout (cKO) mice. In PMN-like PLB-985 silenced for Arf6 fMLP-mediated adhesion to the β2 integrin ligands, ICAM-1 and fibrinogen or the β1/β2 integrin ligand fibronectin was significantly reduced. Furthermore, overexpression of wild-type Arf6 promoted basal and fMLP-induced adhesion to immobilized integrin ligands, while overexpression of the dominant-negative Arf6 has the opposite effects. Using the Elane-Cre deleting mouse strains, we report that the level of Arf6 deletion in inflammatory PMNs isolated from the dorsal air pouches was stronger when compared to naïve cells isolated from the bone marrow. In PMN-Arf6 cKO mice, the recruitment of PMNs into the dorsal air pouch injected with LPS or the chemoattractant fMLP was significantly diminished. Impaired cell migration correlated with reduced cell surface expression of CD11a and CD11b in Arf6 cKO PMNs. Our results highlight that Arf6 regulates the activity and possibly the recycling of PMN integrins, and this compromises PMN migration to inflammatory sites.
- Published
- 2020
- Full Text
- View/download PDF
24. Modulation of muscle protein synthesis by amino acids: what consequences for the secretome? A preliminary in vitro study
- Author
-
Christophe Moinard, Michel Seve, Valérie Cunin, A. Goron, C. Breuillard, Sandrine Bourgoin-Voillard, Laboratory of Fundamental and Applied Bioenergetics = Laboratoire de bioénergétique fondamentale et appliquée (LBFA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and PROteomics and METabolomics Platform [Grenoble] (PROMETHEE)
- Subjects
0301 basic medicine ,Proteomics ,Male ,Hyperaminoacidemia ,Proteome ,[SDV]Life Sciences [q-bio] ,Clinical Biochemistry ,Muscle Fibers, Skeletal ,Muscle Proteins ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,Leucine ,medicine ,Citrulline ,Protein biosynthesis ,Animals ,Amino Acids ,Cells, Cultured ,chemistry.chemical_classification ,030102 biochemistry & molecular biology ,Chemistry ,Myogenesis ,Organic Chemistry ,medicine.disease ,Amino acid ,Culture Media ,030104 developmental biology ,Protein Biosynthesis ,[SDV.AEN]Life Sciences [q-bio]/Food and Nutrition ,Function (biology) - Abstract
International audience; The modulation by amino acids of muscle secretome is largely unknown. In this study, we investigate the effect of hyperaminoacidemia or specific amino acids (citrulline or leucine) on protein synthesis and secretome in myotubes. All conditions stimulate muscle protein synthesis, and secretome is differently modulated depending of the amino acids considered. In conclusion, the activation of protein synthesis by amino acids induces different modulations of the muscle secretome, proposing a new role of amino acids in the regulation of muscle function.
- Published
- 2019
- Full Text
- View/download PDF
25. Phosphatidylserine-specific phospholipase A1: A friend or the devil in disguise
- Author
-
Yang Zhao, Sylvain G. Bourgoin, and Stephan Hasse
- Subjects
Male ,0106 biological sciences ,0301 basic medicine ,Skin Neoplasms ,Hepatitis C virus ,Phosphatidylserines ,Biology ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,Autoimmunity ,03 medical and health sciences ,chemistry.chemical_compound ,Immune system ,Phospholipase A1 ,medicine ,Humans ,Receptor ,Melanoma ,Innate immune system ,Fatty Acids ,Cell Biology ,Phosphatidylserine ,Phospholipases A1 ,3. Good health ,030104 developmental biology ,chemistry ,Apoptosis ,Cancer research ,Lysophospholipids ,010606 plant biology & botany - Abstract
Various human tissues and cells express phospholipase A1 member A (PLA1A), including the liver, lung, prostate gland, and immune cells. The enzyme belongs to the pancreatic lipase family. PLA1A specifically hydrolyzes sn-1 fatty acid of phosphatidylserine (PS) or 1-acyl-lysophosphatidylserine (1-acyl-lysoPS). PS externalized by activated cells or apoptotic cells or extracellular vesicles is a potential source of substrate for the production of unsaturated lysoPS species by PLA1A. Maturation and functions of many immune cells, such as T cells, dendritic cells, macrophages, and mast cells, can be regulated by PLA1A and lysoPS. Several lysoPS receptors, including GPR34, GPR174 and P2Y10, have been identified. High serum levels and high PLA1A expression are associated with autoimmune disorders such as Graves' disease and systemic lupus erythematosus. Increased expression of PLA1A is associated with metastatic melanomas. PLA1A may contribute to cardiometabolic disorders through mediating cholesterol transportation and producing lysoPS. Furthermore, PLA1A is necessary for hepatitis C virus assembly and can play a role in the antivirus innate immune response. This review summarizes recent findings on PLA1A expression, lysoPS and lysoPS receptors in autoimmune disorders, cancers, cardiometabolic disorders, antivirus immune responses, as well as regulations of immune cells.
- Published
- 2021
- Full Text
- View/download PDF
26. Nucleolin Targeting by N6L Inhibits Wnt/β-Catenin Pathway Activation in Pancreatic Ductal Adenocarcinoma
- Author
-
José Cohen, Sandrine Bourgoin-Voillard, Philippe Bouvet, Damien Habert, Mounira Chalabi-Dchar, Claire Houppe, Ilaria Cascone, Mélissande Cossutta, Benoît Vallée, José Courty, Matteo Ponzo, Anais Debesset, Jérôme Cros, Fabio Raineri, Michele Boniotto, Anne Couvelard, Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Centre de Recherche en Cancérologie de Lyon (UNICANCER/CRCL), Centre Léon Bérard [Lyon]-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), AP-HP - Hôpital Bichat - Claude Bernard [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), and COSSUTTA, Mélissande
- Subjects
0301 basic medicine ,Cancer Research ,Pancreatic ductal adenocarcinoma ,endocrine system diseases ,pancreatic ductal adenocarcinoma ,[SDV.CAN]Life Sciences [q-bio]/Cancer ,Article ,03 medical and health sciences ,nucleolin ,0302 clinical medicine ,[SDV.CAN] Life Sciences [q-bio]/Cancer ,In vivo ,[SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Wnt/β-catenin pathway ,tumor microenvironment ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,RC254-282 ,Loss function ,N6L ,Tumor microenvironment ,Chemistry ,Wnt signaling pathway ,Antagonist ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,[SDV.MHEP.HEG]Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology ,[SDV.MHEP.HEG] Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology ,digestive system diseases ,3. Good health ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Catenin ,Cancer research ,cancer therapy ,Nucleolin - Abstract
Simple Summary Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer that has no effective treatment. Nucleolin targeting by the pseudopeptide N6L inhibits the tumor growth and metastasis of pancreatic ductal adenocarcinoma (PDAC). Here, we explored the pathways regulated by nucleolin and N6L in PDAC. We demonstrated that both interact with β-catenin, and that the Wnt/β-catenin pathway is activated in PDAC mouse models. Nucleolin inhibition decreases Wnt/β-catenin pathway activation in PDAC cells and tumors, and represents a new druggable pathway regulated by nucleolin. Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and resistant cancer with no available effective therapy. We have previously demonstrated that nucleolin targeting by N6L impairs tumor growth and normalizes tumor vessels in PDAC mouse models. Here, we investigated new pathways that are regulated by nucleolin in PDAC. We found that N6L and nucleolin interact with β-catenin. We found that the Wnt/β-catenin pathway is activated in PDAC and is necessary for tumor-derived 3D growth. N6L and nucleolin loss of function induced by siRNA inhibited Wnt pathway activation by preventing β-catenin stabilization in PDAC cells. N6L also inhibited the growth and the activation of the Wnt/β-catenin pathway in vivo in mice and in 3D cultures derived from MIA PaCa2 tumors. On the other hand, nucleolin overexpression increased β-catenin stabilization. In conclusion, in this study, we identified β-catenin as a new nucleolin interactor and suggest that the Wnt/β-catenin pathway could be a new target of the nucleolin antagonist N6L in PDAC.
- Published
- 2021
- Full Text
- View/download PDF
27. Hedgehog Pathway–Mediated Vascular Alterations Following Trigeminal Nerve Injury
- Author
-
Yves Boucher, Luis Villanueva, Michel Pohl, Annie Mauborgne, Wisam Dieb, Sylvie Bourgoin, and Nathan Moreau
- Subjects
Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Cyclopamine ,Vascular permeability ,Tight Junctions ,Capillary Permeability ,Rats, Sprague-Dawley ,03 medical and health sciences ,Infraorbital nerve ,chemistry.chemical_compound ,0302 clinical medicine ,Downregulation and upregulation ,Claudin-1 ,medicine ,Animals ,Hedgehog Proteins ,Claudin-5 ,General Dentistry ,Neuroinflammation ,Reverse Transcriptase Polymerase Chain Reaction ,business.industry ,Veratrum Alkaloids ,Trigeminal Neuralgia ,Immunohistochemistry ,Immunity, Innate ,Hedgehog signaling pathway ,Rats ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Microscopy, Fluorescence ,chemistry ,Anesthesia ,Neuropathic pain ,Trigeminal Nerve Injuries ,Endoneurium ,business ,030217 neurology & neurosurgery - Abstract
Whereas neurovascular interactions in spinal neuropathic pain models have been well characterized, little attention has been given to such neurovascular interactions in orofacial neuropathic pain models. This study investigated in male Sprague-Dawley rats the vascular changes following chronic constriction injury (CCI) of the infraorbital nerve (IoN), a broadly validated preclinical model of orofacial neuropathic pain. Following IoN-CCI, an early downregulation of tight junction proteins Claudin-1 and Claudin-5 was observed within the endoneurium and perineurium, associated with increased local accumulation of sodium fluorescein (NaFlu) within the IoN parenchyma, as compared with sham animals. These events were evidence of local blood-nerve barrier disruption and increased vascular permeability. A significant upregulation of immunocytes (CD3, CD11b) and innate immunity (TLR2, TLR4) mRNA markers was also observed, suggestive of increased local inflammation. Finally, a significant downregulation of Hedgehog pathway readouts Patched-1 and Gli-1 was observed within the IoN after CCI and local injections of cyclopamine, a Hedgehog pathway inhibitor, replicated in naïve rats the molecular, vascular, and behavioral changes observed following IoN-CCI. These results suggest a major role of Hedgehog pathway inhibition in mediating local increased endoneurial and perineurial vascular permeability following trigeminal nerve injury, thus facilitating immunocytes infiltration, neuroinflammation development, and neuropathic pain-like aversive behavior.
- Published
- 2016
- Full Text
- View/download PDF
28. Targeting the autotaxin - Lysophosphatidic acid receptor axis in cardiovascular diseases
- Author
-
Stephan Hasse, Chenqi Zhao, Sylvain G. Bourgoin, and Yang Zhao
- Subjects
0301 basic medicine ,Angiogenesis ,medicine.medical_treatment ,Inflammation ,Biochemistry ,Vascular remodelling in the embryo ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Delivery Systems ,Lysophosphatidic acid ,medicine ,Animals ,Humans ,Receptors, Lysophosphatidic Acid ,Pharmacology ,Chemistry ,Cell adhesion molecule ,Phosphoric Diester Hydrolases ,Cell migration ,Cell biology ,030104 developmental biology ,Cytokine ,Cardiovascular Diseases ,030220 oncology & carcinogenesis ,lipids (amino acids, peptides, and proteins) ,medicine.symptom ,Autotaxin - Abstract
Lysophosphatidic acid (LPA) is a well-characterized bioactive lipid mediator, which is involved in development, physiology, and pathological processes of the cardiovascular system. LPA can be produced both inside cells and in biological fluids. The majority of extracellularLPAis produced locally by the secreted lysophospholipase D, autotaxin (ATX), through its binding to various β integrins or heparin sulfate on cell surface and hydrolyzing various lysophospholipids. LPA initiates cellular signalling pathways upon binding to and activation of its G protein-coupled receptors (LPA1-6). LPA has potent effects on various blood cells and vascular cells involved in the development of cardiovascular diseases such as atherosclerosis and aortic valve sclerosis. LPA signalling drives cell migration and proliferation, cytokine production, thrombosis, fibrosis, as well as angiogenesis. For instance, LPA promotes activation and aggregation of platelets through LPA5, increases expression of adhesion molecules in endothelial cells, and enhances expression of tissue factor in vascular smooth muscle cells. Furthermore, LPA induces differentiation of monocytes into macrophages and stimulates oxidized low-density lipoproteins (oxLDLs) uptake by macrophages to form foam cells during formation of atherosclerotic lesions through LPA1-3. This review summarizes recent findings of the roles played by ATX, LPA and LPA receptors (LPARs) in atherosclerosis and calcific aortic valve disease. Targeting the ATX-LPAR axis may have potential applications for treatment of patients suffering from various cardiovascular diseases.
- Published
- 2019
29. Impairment of chemical hypoxia-induced sphingosine kinase-1 expression and activation in rheumatoid arthritis synovial fibroblasts: A signature of exhaustion?
- Author
-
Maria J.G. Fernandes, John A. Di Battista, Nathalie Amiable, David Marsolais, Mélissa Laflamme, Sylvain G. Bourgoin, and Chenqi Zhao
- Subjects
0301 basic medicine ,Chemokine ,Sphingosine-1-phosphate receptor ,Arthritis ,Biochemistry ,Arthritis, Rheumatoid ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Gene silencing ,Humans ,Sphingosine-1-phosphate ,Autocrine signalling ,Sphingosine-1-Phosphate Receptors ,Cells, Cultured ,Pharmacology ,biology ,Chemistry ,Synovial Membrane ,Cobalt ,Fibroblasts ,medicine.disease ,Cell Hypoxia ,Enzyme Activation ,SPHK2 ,Phosphotransferases (Alcohol Group Acceptor) ,030104 developmental biology ,Sphingosine kinase 1 ,030220 oncology & carcinogenesis ,biology.protein ,Cancer research ,Chemokines - Abstract
Sphingosine kinase 1 (SphK1) and 2 (SphK2) have been shown contribute to synovial inflammation in animal models of arthritis. However, low levels of intracellular sphingosine-1 phosphate (S1P) were reported in fibroblast-like synoviocytes (FLS) from patients in the end stage of rheumatoid arthritis (RA) compared to normal FLS. Moreover, the S1P receptor-mediated chemokine synthesis was altered in RAFLS in response to chemical hypoxia. Since the mechanisms responsible for low levels of intracellular S1P in RAFLS are not fully identified, we evaluated the contribution of SphKs to the S1P-induced synthesis of chemokines under conditions of chemical hypoxia. Our results show that a chemical hypoxia mimetic cobalt chloride (CoCl2) increased SphK1 expression and activation in normal FLS but not in RAFLS. Using selective inhibitors of SphKs and gene silencing approaches, we provide evidence that both SphK1 and SphK2 are involved in hypoxia-induced chemokine production in normal FLS. In contrast, only SphK2 mediates hypoxia-induced chemokine production in RAFLS. Moreover, CoCl2 increased S1P2 and S1P3 receptor mRNA levels in normal FLS but not in RAFLS. The data suggest that altered expression and/or activation of SphK1 combined with reduced induction of S1P receptor expression by CoCl2 impaired the CoCl2-mediated autocrine S1P receptor signaling loop and chemokine production in RAFLS.
- Published
- 2018
30. α2- and β2-Adrenoreceptor-Mediated Efficacy of the Atypical Antidepressant Agomelatine Combined With Gabapentin to Suppress Allodynia in Neuropathic Rats With Ligated Infraorbital or Sciatic Nerve
- Author
-
Matthieu Poitevin, Eric Dabala, Cecilia Gabriel, Sylvie Bourgoin, Hugo Payan, Michel Hamon, Saïd M'Dahoma, Elisabeth Mocaer, Institut de psychiatrie et neurosciences (U894 / UMS 1266), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de Recherches Internationales Servier [Suresnes] (IRIS), Neuropsychopharmacologie moléculaire, cellulaire et fonctionnelle, and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)
- Subjects
0301 basic medicine ,Gabapentin ,RS-127445 ,[SDV]Life Sciences [q-bio] ,infraorbital nerve ,sciatic nerve ,Pharmacology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Agomelatine ,Serotonin receptor antagonist ,Pharmacology (medical) ,Melatonin receptor agonist ,chronic constriction injury ,ComputingMilieux_MISCELLANEOUS ,business.industry ,lcsh:RM1-950 ,3. Good health ,030104 developmental biology ,Allodynia ,lcsh:Therapeutics. Pharmacology ,chemistry ,Neuropathic pain ,medicine.symptom ,neuropathic rats ,business ,Idazoxan ,agomelatine ,030217 neurology & neurosurgery ,medicine.drug ,mechanical allodynia - Abstract
Previous data showed that neuropathic pain induced by mechanical lesion of peripheral nerves has specific characteristics and responds differently to alleviating drugs at cephalic versus extracephalic level. This is especially true for tricyclic antidepressants currently used for alleviating neuropathic pain in humans which are less effective against cephalic neuropathic pain. Whether this also applies to the antidepressant agomelatine, with its unique pharmacological properties as MT1/MT2 melatonin receptor agonist and 5-HT2B/5-HT2C serotonin receptor antagonist, has been investigated in two rat models of neuropathic pain. Acute treatments were performed 2 weeks after unilateral chronic constriction (ligation) injury to the sciatic nerve (CCI-SN) or the infraorbital nerve (CCI-ION), when maximal mechanical allodynia had developed in ipsilateral hindpaw or vibrissal pad, respectively, in Sprague-Dawley male rats. Although agomelatine (45 mg/kg i.p.) alone was inactive, co-treatment with gabapentin, at an essentially ineffective dose (50 mg/kg i.p.) on its own, produced marked anti-allodynic effects, especially in CCI-ION rats. In both CCI-SN and CCI-ION models, suppression of mechanical allodynia by 'agomelatine + gabapentin' could be partially mimicked by the combination of 5-HT2C antagonist (SB 242084) + gabapentin, but not by melatonin or 5-HT2B antagonist (RS 127445, LY 266097), alone or combined with gabapentin. In contrast, pretreatment by idazoxan, propranolol or the β2 antagonist ICI 118551 markedly inhibited the anti-allodynic effect of 'agomelatine + gabapentin' in both CCI-SN and CCI-ION rats, whereas pretreatment by the MT1/MT2 receptor antagonist S22153 was inactive. Altogether these data indicate that 'agomelatine + gabapentin' is a potent anti-allodynic combination at both cephalic and extra-cephalic levels, whose action implicates α2- and β2-adrenoreceptor-mediated noradrenergic neurotransmission.
- Published
- 2018
- Full Text
- View/download PDF
31. Crystal structure of the uranyl-oxide mineral rameauite
- Author
-
Jean-Claude Boulliard, Vincent Bourgoin, Radek Škoda, Jiří Čejka, and Jakub Plášil
- Subjects
Oxide minerals ,05 social sciences ,Structural formula ,Crystal structure ,010502 geochemistry & geophysics ,Uranyl ,01 natural sciences ,chemistry.chemical_compound ,Crystallography ,symbols.namesake ,chemistry ,Geochemistry and Petrology ,0502 economics and business ,X-ray crystallography ,symbols ,Molecule ,050211 marketing ,Raman spectroscopy ,0105 earth and related environmental sciences ,Monoclinic crystal system - Abstract
Rameauite is a rare supergene uranyl-oxide hydroxy-hydrate mineral that forms during hydration-oxidation weathering of uraninite. On the basis of single-crystal X-ray diffraction data collected on a microfocus source, rameauite is monoclinic, space group Cc, with a = 13.9458(19), b = 14.3105(19), c = 13.8959(18) A, β = 118.477(14)°, V = 2437.7(6) A 3 and Z = 4, with D calc = 5.467 g cm −3 . The structure of rameauite ( R = 0.060 for 1698 unique observed reflections) contains sheets of the β-U 3 O 8 topology, with both UO 6 and UO 7 bipyramids, which is similar to the sheets found in spriggite, ianthinite and wyartite. The sheets alternate with the interlayer, which contains K + , Ca 2+ and H 2 O molecules. Interstitial cations are linked into infinite chains that extend along [10-1]. Adjacent sheets are linked through K–O, Ca–O and H-bonds. The structural formula of rameauite is K 2 Ca(H 2 [3] O) 1 (H 2 [5] O) 4 [(UO 2 ) 6 O 6 (OH) 4 ](H 2 [4] O) 1 . The empirical formula obtained from the average of eight electron-microprobe analyses is (on the basis of 6 U p.f.u.) K 1.87 (Ca 1.10 Sr 0.04 ) Σ1.14 [(UO 2 ) 6 O 6 (OH) 4.15 ]·6H 2 O. The Raman spectrum is dominated by U–O and O–H vibrations. A discussion of related uranyl-oxide minerals is given.
- Published
- 2016
- Full Text
- View/download PDF
32. Fractionation and proteomic analysis of theWalterinnesia aegyptiasnake venom using OFFGEL and MALDI-TOF-MS techniques
- Author
-
Stéphanie Combemale, Sandrine Bourgoin-Voillard, Mahmoud Fadl, Tarek Mohamed Abd El Aziz, Rémy Béroud, Michel Seve, and Michel De Waard
- Subjects
Chromatography ,biology ,Molecular mass ,Resolution (mass spectrometry) ,Chemistry ,Metal ions in aqueous solution ,Clinical Biochemistry ,Venom ,Fractionation ,biology.organism_classification ,Biochemistry ,Analytical Chemistry ,Matrix-assisted laser desorption/ionization ,Snake venom ,Walterinnesia aegyptia - Abstract
Animal venoms are complex mixtures of more than 100 different compounds, including peptides, proteins, and nonprotein compounds such as lipids, carbohydrates, and metal ions. In addition, the existing compounds show a wide range of molecular weights and concentrations within these venoms, making separation and purification procedures quite tedious. Here, we analyzed for the first time by MS the advantages of using the OFFGEL technique in the separation of the venom components of the Egyptian Elapidae Walterinnesia aegyptia snake compared to two classical methods of separation, SEC and RP-HPLC. We demonstrate that OFFGEL separates venom components over a larger scale of fractions, preserve respectable resolution with regard to the presence of a given compound in adjacent fractions and allows the identification of a greater number of ions by MS (102 over 134 total ions). We also conclude that applying several separating techniques (SEC and RP-HPLC in addition to OFFGEL) provides complementary results in terms of ion detection (21 more for SEC and 22 more with RP-HPLC). As a result, we provide a complete list of 134 ions present in the venom of W. aegyptia by using all these techniques combined.
- Published
- 2015
- Full Text
- View/download PDF
33. Actiflagelin, a new sperm activator isolated from Walterinnesia aegyptia venom using phenotypic screening
- Author
-
Lucie Jaquillard, Michel De Waard, Tarek Mohamed Abd El-Aziz, Mathilde Triquigneaux, Christophe Arnoult, Michel Seve, Sawsan Al Khoury, Guillaume Martinez, Sandrine Bourgoin-Voillard, Rémy Béroud, unité de recherche de l'institut du thorax UMR1087 UMR6291 (ITX), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN), Institute for Advanced Biosciences / Institut pour l'Avancée des Biosciences (Grenoble) (IAB), Centre Hospitalier Universitaire [Grenoble] (CHU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Etablissement français du sang - Auvergne-Rhône-Alpes (EFS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Génétique Chromosomique [CHU de Grenoble], CHU Grenoble, Institut d'oncologie/développement Albert Bonniot de Grenoble (INSERM U823), Institut National de la Santé et de la Recherche Médicale (INSERM)-EFS-CHU Grenoble-Université Joseph Fourier - Grenoble 1 (UJF), PROteomics and METabolomics Platform [Grenoble] (PROMETHEE), Smartox Biotechnology, Université Joseph Fourier - Grenoble 1 (UJF), Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre Hospitalier Universitaire [Grenoble] (CHU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Etablissement français du sang - Auvergne-Rhône-Alpes (EFS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble-EFS-Institut National de la Santé et de la Recherche Médicale (INSERM)
- Subjects
0301 basic medicine ,Snake venom ,lcsh:Arctic medicine. Tropical medicine ,lcsh:RC955-962 ,Tandem mass spectrometry ,Phenotypic screening ,[SDV]Life Sciences [q-bio] ,Acrosome reaction ,Venom ,Toxicology ,Bioactive compounds ,Edman degradation ,De novo sequencing ,03 medical and health sciences ,0302 clinical medicine ,lcsh:RA1190-1270 ,Venomics ,lcsh:Zoology ,lcsh:QL1-991 ,Peptide sequence ,Sperm motility ,lcsh:Toxicology. Poisons ,030219 obstetrics & reproductive medicine ,Walterinnesia aegyptia ,biology ,Chemistry ,biology.organism_classification ,Sperm ,030104 developmental biology ,Infectious Diseases ,Fertility ,Biochemistry ,Animal Science and Zoology ,Parasitology - Abstract
International audience; Background: Sperm contains a wealth of cell surface receptors and ion channels that are required for most of its basic functions such as motility and acrosome reaction. Conversely, animal venoms are enriched in bioactive compounds that primarily target those ion channels and cell surface receptors. We hypothesized, therefore, that animal venoms should be rich enough in sperm-modulating compounds for a drug discovery program. Our objective was to demonstrate this fact by using a sperm-based phenotypic screening to identify positive modulators from the venom ofWalterinnesia aegyptia. Methods: Herein, as proof of concept that venoms contain interesting compounds for sperm physiology, we fractionatedWalterinnesia aegyptiasnake venom by RP-HPLC and screened for bioactive fractions capable of accelerating mouse sperm motility (primary screening). Next, we purified each compound from the positive fraction by cation exchange and identified the bioactive peptide by secondary screening. The peptide sequence was established by Edman sequencing of the reduced/alkylated compound combined to LC-ESI-QTOF MS/MS analyses of reduced/alkylated fragment peptides following trypsin or V8 protease digestion. Results: Using this two-step purification protocol combined to cell phenotypic screening, we identified a new toxin of 7329.38 Da (actiflagelin) that activates sperm motility in vitro from OF1 male mice. Actiflagelin is 63 amino acids in length and contains five disulfide bridges along the proposed pattern of disulfide connectivity C1-C5, C2-C3, C4-C6, C7-C8and C9-C10. Modeling of its structure suggests that it belongs to the family of three finger toxins with a noticeable homology with bucandin, a peptide fromBungarus candidusvenom. Conclusions: This report demonstrates the feasibility of identifying profertility compounds that may be of therapeutic potential for infertility cases where motility is an issue.
- Published
- 2018
- Full Text
- View/download PDF
34. Differential Effects of Inhibitor Combinations on Lysophosphatidic Acid-Mediated Chemokine Secretion in Unprimed and Tumor Necrosis Factor-α-Primed Synovial Fibroblasts
- Author
-
Weili Hui, Chenqi Zhao, and Sylvain G. Bourgoin
- Subjects
0301 basic medicine ,MAPK/ERK pathway ,Chemokine ,medicine.medical_treatment ,CREB Fibroblast-like synoviocytes ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Lysophosphatidic acid ,medicine ,MSK ,Pharmacology (medical) ,Rho-associated protein kinase ,PI3K/AKT/mTOR pathway ,Original Research ,Pharmacology ,biology ,lcsh:RM1-950 ,Cell biology ,body regions ,ERK ,lcsh:Therapeutics. Pharmacology ,030104 developmental biology ,Cytokine ,chemistry ,030220 oncology & carcinogenesis ,Chemokine secretion ,p38MAPK ,biology.protein ,lipids (amino acids, peptides, and proteins) ,Tumor necrosis factor alpha ,tumor necrosis factor-α ,lysophosphatidic acid - Abstract
Lysophosphatidic acid (LPA) is a pleiotropic bioactive lysophospholipid involved in inflammatory mediator synthesis. Signalling through p38MAPK, ERK, Rho kinase, and MSK-CREB contributes to LPA-mediated IL-8 production in fibroblast-like synoviocytes (FLS) from rheumatoid arthritis (RA) patients. The study was undertaken to investigate how LPA activates MSKs and how signalling crosstalk between TNFα and LPA contributes to the super-production of cytokines/chemokines. RAFLS pretreated or not with TNFα were stimulated with LPA. Immunoblotting with phospho-antibodies monitored MSK activation. Cytokine/chemokine production was measured using ELISA and multiplex immunoassays. LPA induced MSK activation by signalling through ERK whereas p38MAPK, Rho kinase, NF-κB or PI3K contribute to IL-8 synthesis mainly via MSK-independent pathways. Priming with TNFα enhanced LPA-mediated MSK phosphorylation and cytokine/chemokine production. After priming with TNFα, inhibition of ERK or MSK failed to attenuate LPA-mediated IL-8 synthesis even if the MSK-CREB signalling axis was completely or partially inhibited. In TNFα-primed cells, inhibition of LPA-mediated cytokine/chemokine synthesis required a specific combination of inhibitors such as p38MAPK and ERK for IL-8 and IL-6, and Rho kinase and NF-κB for MCP-1. The ability of the signalling inhibitors to block LPA induced cytokine/chemokine synthesis is dependent on the inflammatory cytokinic environment. In TNFα-primed RAFLS the super-production of IL-8 and IL-6 induced by LPA occurs mainly via MSK-independent pathways, and simultaneous inhibition of at least two MAPK signalling pathways was required to block their synthesis. Since simultaneous inhibition of both the p38MAPK and ERK-MSK-CREB pathways are required to significantly reduce LPA-mediated IL-8 and IL-6 production in TNFα-preconditioned RAFLS, drug combinations targeting these two pathways are potential new strategies to treat rheumatoid arthritis.
- Published
- 2017
- Full Text
- View/download PDF
35. Initiation of Batrachochytrium dendrobatidis infection in the absence of physical contact with infected hosts - a field study in a high altitude lake
- Author
-
Dirk S. Schmeller, Elodie A. Courtois, Mégane Bourgoin, Adeline Loyau, University of Antwerp (UA), Station d'écologie théorique et expérimentale (SETE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)
- Subjects
0106 biological sciences ,0301 basic medicine ,Ecology ,Batrachochytrium dendrobatidis ,Ecology (disciplines) ,Fungi ,Biology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,mortality ,Toads ,03 medical and health sciences ,Chemistry ,030104 developmental biology ,Altitude ,lakes ,Chytridiomycosis ,Pathogens ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Ecology, Evolution, Behavior and Systematics - Abstract
International audience; Understanding transmission is a critical prerequisite for predicting disease dynamics and impacts on host populations. It is well established that Batrachochytrium dendrobatidis (Bd), the amphibian fungal pathogen responsible for chytridiomycosis, can be transmitted directly, through physical contact with an infected host. However, indirect pathways of transmission remain poorly investigated. We conducted a five‐week long field infection experiment at a high altitude mountain lake in the French Pyrenees to investigate Bd transmission pathways in larval midwife toads Alytes obstetricans. Uninfected naïve tadpoles were co‐housed either with infected tadpoles (direct and indirect transmission) or with uninfected ones (indirect transmission only). We found that physical contact with an infected host is not necessary for initial infection with Bd and that all tadpoles became infected after only four weeks. However, physical contact with infected tadpoles led to a faster spread within a tadpole group and resulted in higher Bd loads and subsequently higher mortality. Our findings clearly demonstrate that in A. obstetricans, Bd can quickly spread in a population even without physical contact. Our experiment therefore stresses the importance of indirect transmission of Bd zoospores in infected lakes for disease dynamics, especially when a reservoir species such as A. obstetricans is present.
- Published
- 2017
- Full Text
- View/download PDF
36. A Phosphorylatable Sphingosine Analog Induces Airway Smooth Muscle Cytostasis and Reverses Airway Hyperresponsiveness in Experimental Asthma
- Author
-
David Gendron, Marie-Renée Blanchet, Marie-Josée Beaulieu, Anne-Marie Lemay, Anthony S. Don, Nicolas Flamand, Carole-Ann Huppé, David Marsolais, Ynuk Bossé, Audrey Lee-Gosselin, Sylvain G. Bourgoin, Mathieu Laplante, Pascale Blais Lecours, and Elyse Y. Bissonnette
- Subjects
0301 basic medicine ,medicine.drug_class ,proliferation ,Cell ,Biology ,Pharmacology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,medicine ,Pharmacology (medical) ,Sphingosine-1-phosphate ,Original Research ,Sphingosine ,Cell growth ,airway hyperresponsiveness ,asthma ,respiratory system ,Receptor antagonist ,airway smooth muscle ,Cytostasis ,respiratory tract diseases ,3. Good health ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,Immunology ,sphingosine-1-phosphate ,sphingosine analog ,Intracellular - Abstract
In asthma, excessive bronchial narrowing associated with thickening of the airway smooth muscle (ASM) causes respiratory distress. Numerous pharmacological agents prevent experimental airway hyperresponsiveness (AHR) when delivered prophylactically. However, most fail to resolve this feature after disease is instated. Although sphingosine analogs are primarily perceived as immune modulators with the ability to prevent experimental asthma, they also influence processes associated with tissue atrophy, supporting the hypothesis that they could interfere with mechanisms sustaining pre-established AHR. We thus assessed the ability of a sphingosine analog (AAL-R) to reverse AHR in a chronic model of asthma. We dissected the pharmacological mechanism of this class of agents using the non-phosphorylatable chiral isomer AAL-S and the pre-phosphorylated form of AAL-R (AFD-R) in vivo and in human ASM cells. We found that a therapeutic course of AAL-R reversed experimental AHR in the methacholine challenge test, which was not replicated by dexamethasone or the non-phosphorylatable isomer AAL-S. AAL-R efficiently interfered with ASM cell proliferation in vitro, supporting the concept that immunomodulation is not necessary to interfere with cellular mechanisms sustaining AHR. Moreover, the sphingosine-1-phosphate lyase inhibitor SM4 and the sphingosine-1-phosphate receptor antagonist VPC23019 failed to inhibit proliferation, indicating that intracellular accumulation of sphingosine-1-phosphate or interference with cell surface S1P1/S1P3 activation, are not sufficient to induce cytostasis. Potent AAL-R-induced cytostasis specifically related to its ability to induce intracellular AFD-R accumulation. Thus, a sphingosine analog that possesses the ability to be phosphorylated in situ interferes with cellular mechanisms that beget AHR.
- Published
- 2017
- Full Text
- View/download PDF
37. Selective mono-radioiodination and characterization of a Cell-Penetrating Peptide: L-Tyr-Maurocalcine
- Author
-
Catherine Ghezzi, Sandrine Cestèle, Pascale Perret, Mitra Ahmadi, Laurent Riou, Marie-Dominique Desruet, Sandrine Bacot, Michel Seve, Cathy Poillot, Morgane Couvet, Michel De Waard, and Sandrine Bourgoin
- Subjects
Chemistry ,Cell-penetrating peptide ,Biophysics ,Maurocalcine ,Physical and Theoretical Chemistry - Abstract
Mono-and poly- iodinated peptides form frequently during radioiodination procedures. However, the formation of a single species in its mono-iodinated form is essential for quantitative studies such as determination of tissue concentration or image quantification. Therefore, the aim of the present study was to define the optimal experimental conditions in order to exclusively obtain the mono-iodinated form of L-maurocalcine (L-MCa). L-MCa is an animal venom toxin which was shown to act as a cell-penetrating peptide. In order to apply the current direct radioiodination technique using oxidative agents including chloramine T, Iodo-Gen® or lactoperoxidase, an analogue of this peptide containing a tyrosine residue (Tyr-L-MCa) was synthesized and was shown to fold/oxidize properly. The enzymatic approach using lactoperoxidase/H2O2 was found to be the best method for radioiodination of Tyr-L-MCa. MALDI-TOF mass spectrometry analyses were then used for identification of the chromatographic eluting components of the reaction mixtures. We observed that the production of different radioiodinated species depended upon the reaction conditions. Our results successfully described the experimental conditions of peptide radioiodination allowing the exclusive production of the mono-iodinated form with high radiochemical purity and without the need for a purification step. Mono-radioiodination of L-Tyr-MCa will be crucial for future quantitative studies, investigating the mechanism of cell penetration and in vivo biodistribution.
- Published
- 2014
- Full Text
- View/download PDF
38. Jasrouxite, a new Pb-Ag-As-Sb member of the lillianite homologous series from Jas Roux, Hautes-Alpes, France
- Author
-
Hubert Putz, Georges Favreau, Emil Makovicky, Georg Zagler, Dan Topa, Jean-Claude Boulliard, and Vincent Bourgoin
- Subjects
Mineralization (geology) ,geography ,geography.geographical_feature_category ,Mineralogy ,Massif ,engineering.material ,Myrmekite ,Homologous series ,chemistry.chemical_compound ,chemistry ,Geochemistry and Petrology ,engineering ,Gangue ,Sedimentary rock ,Anisotropy ,Stibnite ,Geology - Abstract
The thallium-rich sulfosalt deposit of Jas Roux, situated in the Pelvoux Massif (Hautes-Alpesdepartement, France), occurs in a Triassic sedimentary series. Jasrouxite belongs to the early lead-containing stages of the Tl-As-Sb period of mineralization. It occurs in a silicified gangue, along with smithite and late realgar. Jarouxite forms dark gray anhedral grains with metallic luster, up to several millimeters in size, as well as aggregates of grains which range to more than 10 mm in diameter. From their surface, grains of jasrouxite are embayed by a three-phase myrmekite aggregate composed of stibnite, boscardinite and smithite. The mineral is brittle, with irregular fracture; no cleavage or parting was observed. In reflected light, color is off-white. Bireflectance is weak, in off-white tones; anisotropy is distinct. Rare straight twin lamellae occur in otherwise untwinned crystals. The empirical formula, on the basis of 132 apfu derived from the crystal-structure determination, is Cu0.79Ag14.64Pb4.10Tl0.05As15.37Sb24.87S72.18. Calculated density is
- Published
- 2014
- Full Text
- View/download PDF
39. Ultraviolet laser-induced cross-linking in peptides
- Author
-
Sandrine Bourgoin-Voillard, Gabriella Leo, Catherine E. Costello, Leila Birolo, Gennaro Marino, Carlo Altucci, Rosario Esposito, Raffaele Velotta, and Alfredo Maria Gravagnuolo
- Subjects
Spin trapping ,Organic Chemistry ,Analytical chemistry ,Photochemistry ,Laser ,Mass spectrometry ,medicine.disease_cause ,Tandem mass spectrometry ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Covalent bond ,Femtosecond ,Aromatic amino acids ,medicine ,Spectroscopy ,Ultraviolet - Abstract
RATIONALE: The aim of this study was to demonstrate, and to characterize by high-resolution mass spectrometry that it is possible to preferentially induce covalent cross-links in peptides by using high-energy femtosecond ultraviolet (UV) laser pulses. The cross-link is readily formed only when aromatic amino acids are present in the peptide sequence. METHODS: Three peptides, xenopsin, angiotensin I, and interleukin, individually or in combination, were exposed to highenergy femtosecond UV laser pulses, either alone or in the presence of spin trapping molecules, the reaction products being characterized by high resolution mass spectrometry. RESULTS: High-resolution mass spectrometry and spin trapping strategies showed that cross-linking occurs readily, proceeds via a radical mechanism, and is the highly dominant reaction, proceeding without causing significant photodamage in the investigated range of experimental parameters. CONCLUSIONS: High-energy femtosecond UV laser pulses can be used to induce covalent cross-links between aromatic amino acids in peptides, overcoming photo-oxidation processes, that predominate as the mean laser pulse intensity approaches illumination conditions achievable with conventionalUV light sources.Copyright © 2013 John Wiley & Sons, Ltd.
- Published
- 2013
- Full Text
- View/download PDF
40. Origin of the Degradation of Triple Junction Solar Cells at low Temperature
- Author
-
Olivier Cavani, Bruno Boizot, Victor Khorenko, Jacques C. Bourgoin, Seonyong Park, Carsten Baur, Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Azur space, Heilbronn University, European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), and Agence Spatiale Européenne = European Space Agency (ESA)
- Subjects
lcsh:GE1-350 ,Chemistry ,Triple junction ,0211 other engineering and technologies ,02 engineering and technology ,Electron ,[CHIM.MATE]Chemical Sciences/Material chemistry ,010501 environmental sciences ,01 natural sciences ,Fluence ,Depletion region ,Electron beam processing ,Degradation (geology) ,021108 energy ,Irradiation ,Atomic physics ,Quantum tunnelling ,ComputingMilieux_MISCELLANEOUS ,lcsh:Environmental sciences ,0105 earth and related environmental sciences - Abstract
The degradation of solar cells under irradiation by high energy particles (electrons, protons) is the consequence of the introduction of defects trapping minority carriers, which are then not collected by the junction. However, at low temperature, defects located in the space charge region can also induce a tunneling current that results in an apparent decreases of the maximum power. The degradation produced by this tunneling current can depend on temperature, since the concentration of defects created by an irradiation is usually temperature dependent, and can be larger than the degradation associated with carrier recombination. For instance, as we shall see below, an irradiation with 1 MeV electrons at 120 K with a fluence of 3.0 × 10 15 /cm 2 induces a decrease of less than 10 % in the short-circuit current (I sc ) and open-circuit voltage (V oc ) of triple junction (TJ) cells, but a decrease of about 40 % in the maximum power (P max ), which implies that more than half of the total degradation of P max should be assigned to another loss mechanism, tunneling in this case. In this work, we demonstrate that this additional degradation must indeed be ascribed to a tunneling process and we investigate the variation of the tunneling current versus fluence induced by electron irradiation in TJ cells, in order to tentatively ascribe the tunneling components to specific sub-cells.
- Published
- 2017
- Full Text
- View/download PDF
41. Moderate Hyperbilirubinemia Alters Neonatal Cardiorespiratory Control and Induces Inflammation in the Nucleus Tractus Solitarius
- Author
-
Jean-Paul Praud, François Corbin, Nathalie Samson, Maxime M. Richer, Hazim Kadhim, Marie Laure M.L. Specq, Melisande Bourgoin-Heck, Christian Gestreau, Département de pédiatrie [Sherbrooke] (UdeS), Faculté de médecine et des sciences de la santé [Sherbrooke] (UdeS), Université de Sherbrooke (UdeS)-Université de Sherbrooke (UdeS), Université de Sherbrooke (UdeS), Centre de recherche en neurobiologie - neurophysiologie de Marseille (CRN2M), and Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
medicine.medical_specialty ,Respiratory rate ,hyperbilirubinemia ,Bilirubin ,Physiology ,[SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology ,brain ,Pathophysiology ,lcsh:Physiology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Physiologie générale ,030225 pediatrics ,Physiology (medical) ,Internal medicine ,medicine ,Pulmonary and laryngeal chemoreflexes ,Hypoxia ,nucleus tractus solitarius ,pathophysiology ,Hyperbilirubinemia ,Original Research ,Calcium metabolism ,pulmonary and laryngeal chemoreflexes ,lcsh:QP1-981 ,business.industry ,hypoxia ,prematurity ,Brain ,Nucleus tractus solitarius ,Apnea ,Cardiorespiratory fitness ,Hypoxia (medical) ,Endocrinology ,chemistry ,Anesthesia ,Brainstem ,medicine.symptom ,Prematurity ,business ,030217 neurology & neurosurgery - Abstract
Hyperbilirubinemia (HB) occurs in 90% of preterm newborns. Moderate HB can induce acute neurological disorders while severe HB has been linked to a higher incidence of apneas of prematurity. The present study aimed to test the hypothesis that even moderate HB disrupts cardiorespiratory control in preterm lambs. Two groups of preterm lambs (born 14 days prior to term), namely control (n = 6) and HB (n = 5), were studied. At day 5 of life, moderate HB (150-250 μmol/L) was induced during 17 h in the HB group after which cardiorespiratory control as well as laryngeal and pulmonary chemoreflexes were assessed during baseline recordings and during hypoxia. Recordings were repeated 72 h after HB induction, just before euthanasia. In addition, neuropathological studies were performed to investigate for cerebral bilirubin deposition as well as for signs of glial reactivity in brainstem structures involved in cardiorespiratory control. Results revealed that sustained and moderate HB: (i) decreased baseline respiratory rate and increased the time spent in apnea; (ii) blunted the cardiorespiratory inhibition normally observed during both laryngeal and pulmonary chemoreflexes; and (iii) increased heart rate in response to acute hypoxia. These acute physiological changes were concurrent with an activation of Alzheimer type II astrocytes throughout the brain, including the brainstem. Concomitantly, bilirubin deposits were observed in the leptomeninges, but not in brain parenchyma. While most cardiorespiratory alterations returned to normal 72 h after HB normalization, the expression of glial fibrillary acid protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba1) was still increased within the nucleus tractus solitarius. In conclusion, moderate and sustained HB in preterm lambs induced cardiorespiratory alterations, the latter of which were associated with neurohistopathological changes. These changes are indicative of an inflammatory response in the brainstem neuroanatomical substrates involved in cardiorespiratory control., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2016
- Full Text
- View/download PDF
42. Regulation of the proteome by amino acids
- Author
-
Michel Seve, Christophe Moinard, A. Goron, Sandrine Bourgoin-Voillard, Laboratory of Fundamental and Applied Bioenergetics = Laboratoire de bioénergétique fondamentale et appliquée (LBFA), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
- Subjects
0301 basic medicine ,Arginine ,Proteome ,protein synthesis ,Proteolysis ,Glutamine ,[SDV]Life Sciences [q-bio] ,Protein metabolism ,Apoptosis ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Methionine ,Leucine ,Protein biosynthesis ,medicine ,Animals ,Humans ,Molecular Biology ,Citrulline/chemistry ,chemistry.chemical_classification ,amino acids ,030109 nutrition & dietetics ,medicine.diagnostic_test ,TOR Serine-Threonine Kinases ,Amino acid ,030104 developmental biology ,chemistry ,Protein Biosynthesis ,Citrulline ,Signal Transduction - Abstract
International audience; Besides their main contribution as substrates for protein synthesis, amino acids as signaling molecules could exert some regulatory functions on protein synthesis and/or proteolysis that have been emphasized in a number of recent studies. Several publications have highlighted supplemental roles of those amino acids in protein metabolism as well as in immunity, heat shock response, or apoptosis processes. In this way, via their regulatory properties, selected amino acids (such as leucine, glutamine, arginine, citrulline, or methionine) directly influence the proteome. In this review, we are proposing an overview of the regulation of the proteome by amino acids in mammals.
- Published
- 2016
- Full Text
- View/download PDF
43. Prevention of Diabetes in db/db Mice by Dietary Soy Is Independent of Isoflavone Levels
- Author
-
Michelangelo Foti, Serge Nef, Lucie Bourgoin, Céline Zimmermann, and Christopher R. Cederroth
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,030209 endocrinology & metabolism ,Type 2 diabetes ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Diabetes mellitus ,Internal medicine ,medicine ,Animals ,Insulin ,Glucose homeostasis ,ddc:576.5 ,Pancreatic islet function ,ddc:612 ,Pancreas ,030304 developmental biology ,2. Zero hunger ,0303 health sciences ,business.industry ,Gluconeogenesis ,Isoflavones ,medicine.disease ,Diabetes Mellitus, Type 2 ,Liver ,chemistry ,Soybean Proteins ,Insulin Resistance ,Energy Metabolism ,business ,Glycolysis - Abstract
Recent evidence points towards the beneficial use of soy proteins and isoflavones to improve glucose control and slow the progression of type 2 diabetes. Here, we used diabetic db/db mice fed a high soy-containing diet (SD) or a casein soy-free diet to investigate the metabolic effects of soy and isoflavones consumption on glucose homeostasis, hepatic glucose production, and pancreatic islet function. Male db/db mice fed with a SD exhibited a robust reduction in hyperglycemia (50%), correlating with a reduction in hepatic glucose production and preserved pancreatic β-cell function. The rapid decrease in fasting glucose levels resulted from an inhibition of gluconeogenesis and an increase in glycolysis in the liver of db/db mice. Soy consumption also prevented the loss of pancreatic β-cell mass and thus improved glucose-stimulated insulin secretion (3-fold), which partly accounted for the overall improvements in glucose homeostasis. Comparison of SD effects on hyperglycemia with differing levels of isoflavones or with purified isoflavones indicate that the beneficial physiological effects of soy are not related to differences in their isoflavone content. Overall, these findings suggest that consumption of soy is beneficial for improving glucose homeostasis and delaying the progression of diabetes in the db/db mice but act independently of isoflavone concentration.
- Published
- 2012
- Full Text
- View/download PDF
44. GABA, but not opioids, mediates the anti-hyperalgesic effects of 5-HT7 receptor activation in rats suffering from neuropathic pain
- Author
-
Jean-François Bernard, F. Viguier, Sylvie Bourgoin, José-Miguel Vela, Benoit Michot, Michel Hamon, and Valérie Kayser
- Subjects
medicine.medical_specialty ,Real-Time Polymerase Chain Reaction ,Parabrachial area ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Phaclofen ,Interneurons ,Physical Stimulation ,Internal medicine ,Immersion ,Pressure ,medicine ,Animals ,gamma-Aminobutyric Acid ,Pain Measurement ,Pharmacology ,Chemistry ,Bicuculline ,Spinal cord ,Immunohistochemistry ,Rats ,Serotonin Receptor Agonists ,Analgesics, Opioid ,Endocrinology ,medicine.anatomical_structure ,nervous system ,Hyperalgesia ,Receptors, Serotonin ,Anesthesia ,Neuropathic pain ,Neuralgia ,GABAergic ,Serotonin Antagonists ,Sciatic nerve ,Sciatic Neuropathy ,medicine.symptom ,Skin Temperature ,Proto-Oncogene Proteins c-fos ,medicine.drug - Abstract
Among receptors mediating serotonin actions in pain control, the 5-HT(7)R is of special interest because it is expressed by primary afferent fibers and intrinsic GABAergic and opioidergic interneurons within the spinal dorsal horn. Herein, we investigated whether GABA and/or opioids contribute to 5-HT(7)R-mediated control of neuropathic pain caused by nerve ligation. Acute administration of 5-HT(7)R agonists (AS-19, MSD-5a, E-55888) was found to markedly reduce mechanical and thermal hyperalgesia in rats with unilateral constriction injury to the sciatic nerve (CCI-SN). In contrast, mechanical hypersensitivity caused by unilateral constriction injury to the infraorbital nerve was essentially unaffected by these ligands. Further characterization of the anti-hyperalgesic effect of 5-HT(7)R activation by the selective agonist E-55888 showed that it was associated with a decrease in IL-1ß mRNA overexpression in ipsilateral L4-L6 dorsal root ganglia and lumbar dorsal horn in CCI-SN rats. In addition, E-55888 diminished CCI-SN-associated increase in c-Fos immunolabeling in superficial laminae of the lumbar dorsal horn and the locus coeruleus, but increased c-Fos immunolabeling in the nucleus tractus solitarius and the parabrachial area in both control and CCI-SN rats. When injected intrathecally (i.t.), bicuculline (3 μg i.t.), but neither phaclofen (5 μg i.t.) nor naloxone (10 μg i.t.), significantly reduced the anti-hyperalgesic effects of 5-HT(7)R activation (E-55888, 10 mg/kg s.c.) in CCI-SN rats. These data support the idea that 5-HT(7)R-mediated inhibitory control of neuropathic pain is underlain by excitation of GABAergic interneurons within the dorsal horn. In addition, 5-HT(7)R activation-induced c-Fos increase in the nucleus tractus solitarius and the parabrachial area suggests that supraspinal mechanisms might also be involved.
- Published
- 2012
- Full Text
- View/download PDF
45. Zincalstibite-9R: the first nine-layer polytype with the layered double hydroxide structure-type
- Author
-
Georges Favreau, Vincent Bourgoin, Sj Mills, Andrew G. Christy, Jean-Claude Boulliard, A. R. Kampf, and Robert M. Housley
- Subjects
Baryte ,Materials science ,010504 meteorology & atmospheric sciences ,Hydrotalcite ,Layered double hydroxides ,Stacking ,Mineralogy ,chemistry.chemical_element ,Zinc ,Crystal structure ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Crystallography ,chemistry.chemical_compound ,chemistry ,Geochemistry and Petrology ,engineering ,Linarite ,Hydroxide ,0105 earth and related environmental sciences - Abstract
Zincalstibite-9R, a new polytype in the hydrotalcite supergroup is reported from the Monte Avanza mine, Italy. It occurs as pale blue curved disc-like tablets flattened on {001} intergrown to form rosettes typically less than 50 μm in diameter, with cyanophyllite and linarite in cavities in baryte. Zincalstibite-9R is uniaxial (–), with refractive indices ω = 1.647(2) and ε = 1.626(2) measured in white light. The empirical formula (based on 12 OH groups) is (Zn1.092+Cu0.872+Al0.04)Σ2.00Al1.01(Sb0.975+Si0.02)Σ0.99(OH)12, and the ideal formula is (Zn,Cu)2Al(OH)6[Sb(OH)6]. Zincalstibite-9R crystallizes in space group R, with a = 5.340(2), c = 88.01(2) Å, V = 2173.70(15) Å3 and Z = 9. The crystal structure was refined to R1 = 0.0931 for 370 unique reflections [Fo > 4σ(F)] and R1 = 0.0944 for all 381 unique reflections. It has the longest periodic layer stacking sequence for a layered double hydroxide compound reported to date.
- Published
- 2012
- Full Text
- View/download PDF
46. Luminescence Imaging of Extended Defects in SiC via Hyperspectral Imaging
- Author
-
Jean-François Guillemoles, Brett Hull, Marc Verhaegen, Joshua D. Caldwell, Laurent Lombez, Brice Bourgoin, and Amaury Delamarre
- Subjects
Materials science ,business.industry ,Mechanical Engineering ,PIN diode ,Schottky diode ,Hyperspectral imaging ,Electroluminescence ,Condensed Matter Physics ,law.invention ,chemistry.chemical_compound ,chemistry ,Stack (abstract data type) ,Mechanics of Materials ,law ,Silicon carbide ,Optoelectronics ,General Materials Science ,Luminescence ,Spectroscopy ,business - Abstract
Over the past decade, improvements in silicon carbide growth and materials has led to the development of commercialized unipolar devices such as Schottky diodes and MOSFETs, however, much work remains to realizing the goal of wide-scale commercialization of both unipolar and bipolar devices such as pin diodes or IGBTs, for high applications requiring high powers, operating in elevated temperatures or radiation environments or for many fast switching applications. Despite the great strides that have been made in reducing extended and point defect densities during this period, such defects still remain and with the push to lower off-cut angle substrates are in many cases seeing increases in prevalence. Thus, spectroscopic and imaging techniques for locating and identifying these defects are in high demand. Luminescence imaging and spectroscopy have both been utilized heavily in such work, yet simultaneously obtaining corresponding spectroscopic and spatial information from such defects is problematic. Here we report on hyperspectral imaging of electroluminescence from SiC pin diodes, whereby a stack of luminescence images are collected over a wide spectral range (400-900 nm), thereby providing the ability to both image distinct features and identify their corresponding spectral properties. This process is also equally applicable to collecting either photo- or electroluminescence from other materials or devices emitting in either the UV-Vis or NIR spectral range, as well as to reflectance, transmission or other imaging techniques.
- Published
- 2012
- Full Text
- View/download PDF
47. Biophysical studies of the interaction between calmodulin and the R287-T311 region of human estrogen receptor α reveals an atypical binding process
- Author
-
Yves Jacquot, Magali Nicaise, Guy Leclercq, Ludovic Carlier, Cillian Byrne, Michel Desmadril, Emeric Miclet, Sandrine Bourgoin-Voillard, Jean-Claude Tabet, and Olivier Lequin
- Subjects
chemistry.chemical_classification ,0303 health sciences ,Calmodulin ,biology ,Biophysics ,Estrogen receptor ,Isothermal titration calorimetry ,Peptide ,Cell Biology ,Nuclear magnetic resonance spectroscopy ,Biochemistry ,Fluorescence spectroscopy ,Dissociation constant ,03 medical and health sciences ,0302 clinical medicine ,chemistry ,Transcription (biology) ,030220 oncology & carcinogenesis ,biology.protein ,Molecular Biology ,030304 developmental biology - Abstract
The transcriptional activity of human estrogen receptor ERa is modulated by a number of coregulatory proteins among which calmodulin (CaM). Segment 295–311 in the hinge region of ERa has previously been proposed to be the CaM binding site. In this work, we investigate the molecular mechanism of the interaction of CaM with peptides derived from the hinge region of ERa, using a biophysical approach combining isothermal titration calorimetry, fluorescence, CD and NMR. The ERa17p peptide, corresponding to the previously identified 295–311 region of ERa, recruits mainly the C-terminal domain of Ca4CaM, as shown by NMR spectroscopy. In contrast, a longer peptide, ERa25p, extended on the N-terminal side (residues 287–311) interacts with both N- and C-terminal domains of Ca4CaM. These results lead to a new delineation of the CaM binding site, encompassing residues 287–294. In particular, fluorescence spectroscopy reveals that the conserved W 292 residue is engaged within hydrophobic pockets on Ca4CaM. ITC results show that ERa25p binds Ca4CaM with an atypical 2:1 stoichiometry and a dissociation constant in the micromolar range. Based on the NMR titration of Ca4CaM by ERa25p showing a biphasic behavior for several residues, we suggest that concerted conformational changes of CaM domains may be required to accommodate the binding of a second peptide. CD spectra indicate that ERa25p partially folds into an a-helix upon binding to Ca4CaM. Hence, ERa25p is a new CaM-binding ligand that could be appropriate for the synthesis of derivatives able to control ER-dependent transcription, particularly in the context of hormone-dependent breast tumors.
- Published
- 2012
- Full Text
- View/download PDF
48. Facile decoration of functionalized single-wall carbon nanotubes with phthalocyanines via 'click chemistry'
- Author
-
Campidelli, Stephane, Ballesteros, Beatriz, Filoramo, Arianna, Diaz, David Diaz, de la Torre, Gema, Torres, Tomas, Rahman, G.M. Aminur, Ehli, Christian, Kiessling, Daniel, Werner, Fabian, Sgobba, Vito, Guldi, Dirk M., Cioffl, Carla, Prato, Maurizio, and Bourgoin, Jean-Philippe
- Subjects
Nanotubes -- Spectra ,Nanotubes -- Chemical properties ,Phthalocyanins -- Spectra ,Phthalocyanins -- Chemical properties ,Zinc compounds -- Spectra ,Zinc compounds -- Chemical properties ,Chemistry - Abstract
The functionalization of single-wall carbon nanotubes (SWNTs) with 4-(2-trimethylsilyl)ethynylaniline and the subsequent attachment of a zinc-phthalocyanine (ZnPc) derivative is described by using the reliable Huisgen 1,3-dipolar cycloaddition. The SWNT-ZnPc nanoconjugate is examined with a series of steady-state and time-resolved spectroscopy experiments and a photoinduced communication between the two photoactive components are identified.
- Published
- 2008
49. Calmodulin association with the synthetic ERα17p peptide investigated by mass spectrometry
- Author
-
Françoise Fournier, Carlos Afonso, Jean-Claude Tabet, Yves Jacquot, Guy Leclercq, and Sandrine Bourgoin-Voillard
- Subjects
Electrospray ,Calmodulin ,Stereochemistry ,chemistry.chemical_element ,Peptide ,Sequence (biology) ,Calcium ,Mass spectrometry ,01 natural sciences ,Melittin ,03 medical and health sciences ,chemistry.chemical_compound ,Physical and Theoretical Chemistry ,Instrumentation ,Spectroscopy ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Chromatography ,biology ,Chemistry ,010401 analytical chemistry ,Condensed Matter Physics ,Affinities ,0104 chemical sciences ,biology.protein - Abstract
Implication of calmodulin (CaM) in breast cancer development has been proposed, justifying the interest for ER/calmodulin interaction. The association of the synthetic peptide ERα17p (H–PLMIKRSKKNSLALSLT–OH), which corresponds to the known ER interaction site of CaM, was investigated. Under physiologically conditions, 1:1 complex formation was observed using an ESI-ITMS instrument. This equimolar complex with CaM was only formed in presence of calcium. The binding of ERα17p to CaM is probably due to presence of four basic residues (K299RSKK303) in its sequence. Its relative binding affinity in solution by ESI-MS was evaluated by performing competitive binding experiments with other peptides more (ERα17pKR: KRSKR) or less basic (ERα17pAA: KRSAA) than ERα17p as well as Melittin (Mel), selected as a reference peptide since it is known to form a high-affinity complex with CaM. Relative affinities of these peptides for CaM were classified in the following decreasing order: Mel > ERα17pKR ∼ ERα17p ≫ ERα17pAA. Interestingly, another ion series showing two peptides for one protein was detected. The specificity of this complex not often reported for Melittin is discussed.
- Published
- 2011
- Full Text
- View/download PDF
50. TNF-α promotes LPA1- and LPA3-mediated recruitment of leukocytes in vivo through CXCR2 ligand chemokines[S]
- Author
-
Chenqi Zhao, Anne Sardella, Maria J.G. Fernandes, Sylvain G. Bourgoin, Jerold Chun, and Patrice E. Poubelle
- Subjects
medicine.medical_specialty ,Chemokine ,Time Factors ,Phosphatidic Acids ,Inflammation ,QD415-436 ,Ligands ,Biochemistry ,Receptors, Interleukin-8B ,chemistry.chemical_compound ,Gene Knockout Techniques ,Mice ,Endocrinology ,In vivo ,Internal medicine ,Lysophosphatidic acid ,medicine ,Leukocytes ,Animals ,CXC chemokine receptors ,Receptors, Lysophosphatidic Acid ,Receptor ,Research Articles ,biology ,Dose-Response Relationship, Drug ,Tumor Necrosis Factor-alpha ,Organothiophosphates ,Chemotaxis ,Cell Biology ,Cell biology ,chemistry ,LPA receptor agonist/antagonist ,LPA receptor deficient mice ,inflammation ,biology.protein ,Tumor necrosis factor alpha ,Female ,lipids (amino acids, peptides, and proteins) ,CXC chemokines ,medicine.symptom ,Chemokines ,Lysophospholipids ,biological phenomena, cell phenomena, and immunity ,murine air pouch model - Abstract
Lysophosphatidic acid (LPA) is a bioactive lysophospholipid present in low concentrations in serum and biological fluids but in high concentrations at sites of inflammation. LPA evokes a variety of cellular responses via binding to and activation of its specific G protein-coupled receptors (GPCR), namely LPA(1-6). Even though LPA is a chemoattractant for inflammatory cells in vitro, such a role for LPA in vivo remains largely unexplored. In the present study, we used the murine air pouch model to study LPA-mediated leukocyte recruitment in vivo using selective LPA receptor agonist/antagonist and LPA(3)-deficient mice. We report that 1) LPA injection into the air pouch induced leukocyte recruitment and that both LPA(1) and LPA(3) were involved in this process; 2) LPA stimulated the release of the pro-inflammatory chemokines keratinocyte-derived chemokine (KC) and interferon-inducible protein-10 (IP-10) in the air pouch; 3) tumor necrosis factor-α (TNF-α) injected into the air pouch prior to LPA strongly potentiated LPA-mediated secretion of cytokines/chemokines, including KC, IL-6, and IP-10, which preceded the enhanced leukocyte influx; and 4) blocking CXCR2 significantly reduced leukocyte infiltration. We suggest that LPA, via LPA(1) and LPA(3) receptors, may play a significant role in inducing and/or sustaining the massive infiltration of leukocytes during inflammation.
- Published
- 2011
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.