Consulta: creatorFacets:"Roch, Philippe"
Registros recuperados: 6
Data/hora: 05/06/2024 16:45:45

Défense et résistance chez les invertébrés marins
Provedor de dados: 5
Autores: Roch, Philippe.
Durant de nombreuses années, faire de la biologie a consisté en la description des processus qui gouvernent le monde vivant. Le développement de la biochimie et surtout l'explosion récente de la biologie moléculaire en ont fait une science d'intervention permettant de modifier les organismes vivants.
Tipo: Text
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/publication-7480.pdf

Lysozyme gene expression and hemocyte behaviour in the Mediterranean mussel, Mytilus galloprovincialis, after injection of various bacteria or temperature stresses
Provedor de dados: 5
Autores: Li, H; Parisi, M; Toubiana, Mylene; Cammarata, M; Roch, Philippe.
The aim of the present study was to evaluate the expression of the Mytilus galloprovincialis lysozyme gene in different in vivo stress situations, including injection of bacteria Vibrio splendidus LGP32, Vibrio anguillarum or Micrococcus lysodeikticus, as well as heat shock at 30 C and cold stress at 5 C. Injection of V. splendidus LGP32 resulted in: (i) a general down-regulation of lysozyme gene expression, as quantified by Q-PCR; (ii) reduction in the number of circulating hemocytes; (iii) decrease in the percentage of circulating hemocytes expressing lysozyme mRNA which was now restricted to only small cells, as observed by ISH; and (iv) accumulation of hemocytes expressing lysozyme in the muscle sinus where injection took place. Injection of V....
Tipo: Text
Palavras-chave: Molluscs; Mytilus; ISH; Q PCR; Gene expression; Lysozyme; Heat shock; Micrococcus lysodeikticus; Vibrio anguillarum; Vibrio splendidus.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4479.pdf

Cytotoxic and antibacterial properties of Mytilus galloprovincialis, Ostrea edulis and Crassostrea gigas (bivalve molluscs) hemolymph
Provedor de dados: 5
Autores: Hubert, Florence; Van Der Knaap, Wil; Noel, Thierry; Roch, Philippe.
Mussel (Mytilus galloprovincialis) plasma contains cytotoxic activity against both vertebrate (erythrocytes and mouse tumour) and protozoan cells. Procaryotes (Escherichia coli and Vibrio alginolyticus) were not sensitive to the cytotoxicity. The activity was still present in dialyzed samples but was inhibited by heating at 45°C. Large individual variability which was not correlated with protein concentration and an increasing number of reactive specimens following injection, suggested that naive mussels were in various stages of immune response. Purification by anion exchange chromatography followed by gel filtration revealed a 320 kDa cytotoxic polymeric protein that acts through a polymerization process after binding onto target cell membranes as...
Tipo: Text
Palavras-chave: Cytotoxicité; Antibactérien; Hémolymphe; Lysat d'hémocyte; Moule; Huître; Mytilus galloprovincialis; Ostrea edulis; Crassostrea gigas; Cytotoxicity; Antibacterial; Hemolymph; Hemocyte lysate; Musssel; Oyster; Mytilus galloprovincialis; Ostrea edulis; Crassostrea gigas.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00039/15008/12333.pdf

Differential distribution and defence involvement of antimicrobial peptides in mussel
Provedor de dados: 5
Autores: Mitta, Guillaume; Vandenbulcke, Franck; Noel, Thierry; Romestand, Bernard; Beauvillain, Jean Claude; Salzet, Michel; Roch, Philippe.
In previous papers, we characterised 3 types of 4-kDa, cysteine-rich, cationic antimicrobial peptides: MGDs (for Mytilus galloprovincialis defensins), mytilins and myticins, which are abundant in the mussel hemocytes. In the present work, me revealed a differential distribution of the cells expressing the different genes. In addition, using confocal and electron microscopy, we confirmed that defensins and mytilins were partially located in different sub-types of circulating hemocytes although the peptides can be located in the same cell, and even in the same granule. We also demonstrated that mytilins exert their microbicidal effect within the cells through the process of phagosome-mytilin granule fusion leading to the co-location of ingested bacteria and...
Tipo: Text
Palavras-chave: Innate immunity; Hemocyte; Mussel; Myticin; Mytilin; Defensin; Antimicrobial.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-413.pdf

NMR structure of mussel mytilin, and antiviral-antibacterial activities of derived synthetic peptides
Provedor de dados: 5
Autores: Roch, Philippe; Yang, Y; Toubiana, Mylene; Aumelas, A.
Mytilin is a 34-residue antibacterial peptide from the mussel Mytilus galloprovincialis, which in addition possesses in vitro antiviral activity. The three-dimensional solution structure of the synthetic mytilin was established by using 1H NMR and consists of the common cysteine-stabilized alpha beta motif close to the one observed in the mussel defensin MGD-1. Mytilin is characterized by 8 cysteines engaged in four disulfide bonds (2-27, 6-29, 10-31, and 15-34) only involving the beta-strand II. Hydrophilic and hydrophobic areas of mytilin account for 63% and 37%, respectively, a ratio very close to that of MGD-1 (64% and 36%). One linear and three cyclic fragments were designed from the interstrand loop sequence known to retain the biological activities...
Tipo: Text
Palavras-chave: Shrimp; Molluscs; Mussel; Antibacterial activity; WSSV; Viral protection; Beta hairpin structure; NMR; Mytilin; Antimicrobial peptide.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4485.pdf

Influence of temperature, salinity and E. coli tissue content on immune gene expression in mussel: Results from a 2005-2008 survey
Provedor de dados: 5
Autores: Li, Hui; Toubiana, Mylene; Monfort, Patrick; Roch, Philippe.
Several bivalves, including mussels, suffered from mortalities particularly in summer. To look for the possible effect of environmental parameters on immune capacities, Mytilus galloprovincialis were collected monthly from August 2005 to July 2008 from the Palavas Laguna, French Mediterranean coast. Q-PCR was used to quantify the expression of three antimicrobial peptide genes (defensin, mytilin B and myticin B), in addition to lysozyme and HSP70. House keeping gene was 28S rRNA. Defensin, myticin B and lysozyme appeared more expressed in spring-summer than in winter. In contrast, HSP70 expression was higher in winter. Statistical studies using principal component analysis (PCA) and multiple regression models revealed positive influence of temperature on...
Tipo: Text
Palavras-chave: Mollusks; Mytilus; Innate immunity; Seasonal variations; Immune survey; Q PCR; HSP70; Lysozyme; Myticin; Mytilin; Defensin; Antimicrobial peptide.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-7345.pdf