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Registros recuperados: 52 | |
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Frere, Laura; Maignien, Lois; Chalopin, Morgane; Huvet, Arnaud; Rinnert, Emmanuel; Morrison, Hilary; Kerninon, Sandrine; Cassone, Anne-laure; Lambert, Christophe; Reveillaud, Julie; Paul-pont, Ika. |
Microplastics (<5 mm) exhibit intrinsic features such as density, hydrophobic surface, or high surface/volume ratio, that are known to promote microbial colonization and biofilm formation in marine ecosystems. Yet, a relatively low number of studies have investigated the nature of microplastic associated bacterial communities in coastal ecosystems and the potential factors influencing their composition and structure. Here, we characterized microplastics collected in the Bay of Brest by manual sorting followed by Raman spectroscopy and studied their associated bacterial assemblages using 16S amplicon high-throughput sequencing. Our methodology allowed discriminating polymer type (polyethylene, polypropylene and polystyrene) within small size ranges... |
Tipo: Text |
Palavras-chave: Bacteria; Microplastics; Coastal ecosystem; Metabarcoding; Vibrios. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00449/56082/57614.pdf |
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Dehaut, Alexandre; Cassone, Anne-laure; Frere, Laura; Hermabessiere, Ludovic; Himber, Charlotte; Rinnert, Emmanuel; Riviere, Gilles; Lambert, Christophe; Soudant, Philippe; Huvet, Arnaud; Duflos, Guillaume; Paul-pont, Ika. |
Pollution of the oceans by microplastics (<5 mm) represents a major environmental problem. To date, a limited number of studies have investigated the level of contamination of marine organisms collected in situ. For extraction and characterization of microplastics in biological samples, the crucial step is the identification of solvent(s) or chemical(s) that efficiently dissolve organic matter without degrading plastic polymers for their identification in a time and cost effective way. Most published papers, as well as OSPAR recommendations for the development of a common monitoring protocol for plastic particles in fish and shellfish at the European level, use protocols containing nitric acid to digest the biological tissues, despite reports of... |
Tipo: Text |
Palavras-chave: Microplastics; Digestion; Method; Seafood products; Tissue; Plastic integrity. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00335/44582/44469.pdf |
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Tallec, Kevin; Huvet, Arnaud; Di Poi, Carole; Gonzalez-fernandez, Carmen; Lambert, Christophe; Petton, Bruno; Le Goic, Nelly; Berchel, Mathieu; Soudant, Philippe; Paul-pont, Ika. |
In the marine environment, most bivalve species base their reproduction on external fertilization. Hence, gametes and young stages face many threats, including exposure to plastic wastes which represent more than 80% of the debris in the oceans. Recently, evidence has been produced on the presence of nanoplastics in oceans, thus motivating new studies of their impacts on marine life. Because no information is available about their environmental concentrations, we performed dose-response exposure experiments with polystyrene particles to assess the extent of micro/nanoplastic toxicity. Effects of polystyrene with different sizes and functionalization (plain 2-μm, 500-nm and 50-nm; COOH-50 nm and NH2-50 nm) were assessed on three key reproductive steps... |
Tipo: Text |
Palavras-chave: Oyster; Embryos; Gametes; Microplastics; Nanoplastics. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00453/56419/58090.pdf |
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Samain, Jean-francois; Degremont, Lionel; Soletchnik, Patrick; Ropert, Michel; Bedier, Edouard; Mazurie, Joseph; Mazurie, Joseph; Martin, Jean-louis; Moal, Jeanne; Mathieu, Michel; Pouvreau, Stephane; Lambert, Christophe; Escoubas, Jean-michel; Nicolas, Jean-louis; Le Roux, Frédérique; Renault, Tristan; Burgeot, Thierry; Bacher, Cedric; Boudry, Pierre. |
Complex interactions between oyster, environment and pathogens were observed during the MOREST (2001-2005) project on summer mortality events of Crassostrea gigas oysters in France. The talk will show how nutrition level increasing reproductive intensity generates a risk for pathogen infection under synergistic effect of temperature and stress. Moreover, a genetic component is associated to specific reproductive performances and spawning behaviour. To better understand origin of such resistance or susceptibility to summer mortality, other characteristics as stress susceptibility, energy management and hemocyte activities of oysters from the two phenotypes were compared. This first comparison suggests interactions between stress, reproduction and defence... |
Tipo: Text |
Palavras-chave: Genetic; Pathologie; Mortality; Crassostrea gigas; Pacific oyster; Reproduction; Nutrition; Physilogy. |
Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/2006/acte-3467.pdf |
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Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goic, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-pont, Ika; Soudant, Philippe; Huvet, Arnaud. |
Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L−1) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS... |
Tipo: Text |
Palavras-chave: Microplastic; Reproduction; Energy allocation; Oyster. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00311/42233/41600.pdf |
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Lassudrie, Malwenn; Soudant, Philippe; Richard, Gaelle; Henry, N.; Medhioub, Walid; Da Silva, P.m.; Donval, Anne; Bunel, M.; Le Goïc, Nelly; Lambert, Christophe; De Montaudoin, X.; Fabioux, Caroline; Hegaret, Helene. |
Manila clam stock from Arcachon Bay, France, is declining, as is commercial harvest. To understand the role of environmental biotic interactions in this decrease, effects of a toxic dinoflagellate, Alexandrium ostenfeldii, which blooms regularly in Arcachon bay, and the interaction with perkinsosis on clam physiology were investigated. Manila clams from Arcachon Bay, with variable natural levels of perkinsosis, were exposed for seven days to a mix of the nutritious microalga T-Iso and the toxic dinoflagellate A. ostenfeldii, a producer of spirolides, followed by seven days of depuration fed only T-Iso. Following sacrifice and quantification of protozoan parasite Perkinsus olseni burden, clams were divided into two groups according to intensity of the... |
Tipo: Text |
Palavras-chave: Bivalve; Harmful algal bloom; Oxidative stress; Venerupis philippinarum; Alexandrium ostenfeldii; Perkinsus olseni.. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00189/30022/28507.pdf |
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Piel, Damien; Bruto, Maxime; James, Adele; Labreuche, Yannick; Lambert, Christophe; Janicot, Adrian; Chenivesse, Sabine; Petton, Bruno; Wegner, K. Mathias; Stoudmann, Candice; Blokesch, Melanie; Le Roux, Frederique. |
Pacific oyster mortality syndrome affects juveniles of Crassostrea gigas oysters and threatens the sustainability of commercial and natural stocks of this species. Vibrio crassostreae has been repeatedly isolated from diseased animals and the majority of the strains have been demonstrated to be virulent for oysters. In this study we showed that oyster farms exhibited a high prevalence of a virulence plasmid carried by V. crassostreae while oysters, at an adult stage, were reservoirs of this virulent population. The pathogenicity of V. crassostreae depends on a novel transcriptional regulator, which activates the bidirectional promoter of a Type 6 Secretion System (T6SS) genes cluster. Both the T6SS and a second chromosomal virulence factor, r5.7, are... |
Tipo: Text |
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Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00510/62129/66343.pdf |
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Rahmani, Alexandra; Corre, Erwan; Richard, Gaëlle; Bidault, Adeline; Lambert, Christophe; Oliveira, Louisi; Thompson, Cristiane; Thompson, Fabiano; Pichereau, Vianney; Paillard, Christine. |
The Brown Ring Disease is an infection caused by the bacterium Vibrio tapetis on the Manila clam Ruditapes philippinarum. The process of infection, in the extrapallial fluids (EPFs) of clams, involves alteration of immune functions, in particular on hemocytes which are the cells responsible of phagocytosis. Disorganization of the actin-cytoskeleton in infected clams is a part of what leads to this alteration. This study is the first transcriptomic approach based on collection of extrapallial fluids on living animals experimentally infected by V. tapetis. We performed differential gene expression analysis of EPFs in two experimental treatments (healthy-against infected-clams by V. tapetis), and showed the deregulation of 135 genes. In infected clams, a... |
Tipo: Text |
Palavras-chave: Brown ring disease; V. tapetis; R. philippinarum; Hemocytes; Actin cytoskeleton; Beta-Thymosin; Coactosin; Resting cells. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00510/62131/66362.pdf |
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Labreuche, Yannick; Le Roux, Frederique; Henry, Joel; Zatylny, Celine; Huvet, Arnaud; Lambert, Christophe; Soudant, Philippe; Mazel, Didier; Nicolas, Jean-louis. |
Extracellular products (ECPs) of the pathogenic Vibrio aestuarianus 01/32 were previously reported to display lethality in Crassostrea gigas oysters and to cause morphological changes and immunosuppression in oyster hemocytes. To identify the source of this toxicity, biochemical and genetic approaches were developed. ECP protease activity and lethality were shown to be significantly reduced following incubation with metal chelators, suggesting the involvement of a zinc metalloprotease. An open reading frame of 1836 bp encoding a 611-aa metalloprotease (designated yam) was identified. The deduced protein sequence showed high homology to other Vibrio metalloproteases reported to be involved in pathogenicity. To further confirm the role of this enzyme in ECP... |
Tipo: Text |
Palavras-chave: Vibrio aestuarianus; Metalloprotease; Crassostrea gigas; Oyster; Hemocytes; Extracellular products. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00015/12649/9588.pdf |
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Paillard, Christine; Nicolas, Jean-louis; Le Chevalier, Patrick; Lambert, Christophe; Le Boulay, Christine; Berthe, Franck; Haras, Dominique. |
The emergence of new vibriosis in the European Atlantic coasts has been associated with mass mortalities of molluscs causing important economic losses. For examples, Vibrio carchariae, a bacteria already isolated from shark, has been associated with a severe Haliotis epizooty in hatchery. In oysters, Crass()strea gigas, a strain closely related to Vibrio splendidus is suspected to be associated with summer mortalities. |
Tipo: Text |
Palavras-chave: Pathogenic vibrios; Bivales; Vibriosis; Bacteriology. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/acte-3287.pdf |
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Registros recuperados: 52 | |
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