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Registros recuperados: 109 | |
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Droguet, Mickael; Devauchelle, Nicole; Pennec, Jean-pierre; Quinn, Brian; Dorange, Germaine. |
European Community regulations on chemicals promote alternative methods to test substances presenting potential risks for the environment. In the present work, cultured atrial cells isolated from oyster (Crassostrea gigas) were used as an experimental model to investigate the toxicity of tributyltin (TBT) after short-time exposure at concentrations representative of those that can be measured in seawater, marine sediments and/or bivalves bioaccumulating this pollutant. In vitro and in vivo assays produce values of the same order of magnitude for both animal/cell survival and heart/cardiomyocyte beating rate. The survival rate of whole animals decreased from 10(-6) M TBT after 3 days. For cultured cells, the viability, evaluated using 3-(4,... |
Tipo: Text |
Palavras-chave: Oyster; Heart cells; Flow cytometry; Tributyltin; Toxicity; Antifouling. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00089/20032/17688.pdf |
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Moreau, Pierrick; Burgeot, Thierry; Renault, Tristan. |
Pollutants via run-off into the ocean represent a potential threat to marine organisms, especially bivalves such as oysters living in coastal environments. These organisms filter large volumes of seawater and may accumulate contaminants within their tissues. Pesticide contamination in water could have a direct or indirect toxic action on tissues or cells and could induce alteration of immune system. Bivalve immunity is mainly supported by hemocytes and participates directly by phagocytosis to eliminate pathogens. Some studies have shown that pesticides can reduce immune defences and/or modify genomes in vertebrates and invertebrates. Metaldehyde is used to kill slugs, snails and other terrestrial gastropods. Although metaldehyde has been detected in... |
Tipo: Text |
Palavras-chave: Immunity; Hemocytes; Metaldehyde; Pacific oyster; Flow cytometry; In vivo; Genetic diversity. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00195/30602/29059.pdf |
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Gervais, Ophelie; Renault, Tristan; Arzul, Isabelle. |
Apoptosis is a fundamental feature in the development of many organisms and tissue systems. It is also a mechanism of host defense against environmental stress factors or pathogens by contributing to the elimination of infected cells. Hemocytes play a key role in defense mechanisms in invertebrates and previous studies have shown that physical or chemical stress can increase apoptosis in hemocytes in mollusks. However this phenomenon has rarely been investigated in bivalves especially in the flat oyster Ostrea edulis. The apoptotic response of hemocytes from flat oysters, O. edulis, was investigated after exposure to UV and dexamethasone, two agents known to induce apoptosis in vertebrates. Flow cytometry and microscopy were combined to demonstrate that... |
Tipo: Text |
Palavras-chave: Apoptosis; Hemocyte(s); Oyster; Ostrea edulis; UV; Flow cytometry; Microscopy. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00270/38160/36295.pdf |
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Chretiennot-dinet, Marie-josèphe; Vaulot, Daniel; Galois, Robert; Spano, Anna-maria; Robert, Rene. |
The ingestion of 8 algal species by oyster larvae (Crassostrea gigas Thunberg, 1793) was measured by flow cytometry (FCM). In a preliminary experiment, cell size (estimated by light scatter) and chlorophyll fluorescence of 30 algal species were evaluated to select those species which could be mixed together and still be easily discriminated by FCM. Grazing experiments were carried out over 48 h with 6 and 15-day old larvae fed on 3 algal mixtures, each containing 3 different algal species. The concentration of each species was estimated at 0, 6, 12, 24 and 48 h by FCM. Grazing pressure on a given algal species was dependent upon the age of the larvae, the time of the day and the composition of the mixture. Grazing rates of older larvae were about twice... |
Tipo: Text |
Palavras-chave: Oyster larvae; Crassostrea gigas; Grazing; Algae; Selective feeding; Flow cytometry. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/00090/20164/17817.pdf |
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Fernández-boo, Sergio; Gervais, Ophelie; Prado-alvarez, Maria; Chollet, Bruno; Claverol, Stéphane; Lecadet, Cyrielle; Dubreuil, Christine; Arzul, Isabelle. |
Bonamia ostreae is an intrahemocytic parasite that has been responsible for severe mortalities in the flat oyster Ostrea edulis since the 1970́s. The Pacific oyster Crassostrea gigas is considered to be resistant to the disease and appears to have mechanisms to avoid infection. Most studies carried out on the invertebrate immune system focus on the role of hemolymph, although mucus, which covers the body surface of molluscs, could also act as a barrier against pathogens. In this study, the in vitro effect of mucus from the oyster species Ostrea edulis and C. gigas on B. ostreae was investigated using flow cytometry. Results showed an increase in esterase activities and mortality rate of parasites exposed to mucus from both oyster species. In order to... |
Tipo: Text |
Palavras-chave: Bonamia ostreae; Crassostrea gigas; Ostrea edulis; Flow cytometry; Immune response; Proteome. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00594/70602/68795.pdf |
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Choquet, Gwenaelle; Soudant, P; Lambert, C; Nicolas, Jean-louis; Paillard, C. |
Vibrio tapetis is the causative agent of brown ring disease (BRD), which affects a species of clam, Ruditapes philippinarum. After incubation with V. tapetis, hemocytes lose filopods and become rounded, indicating cytotoxic activity of the bacterium. To rapidly quantify this cytotoxicity, a flow-cytometry test was developed based on the capacity of V tapetis to inhibit adhesion of clam hemocytes to plastic. Several bacteria:hemocyte ratios, the cytotoxicity of other Vibrio spp. pathogenic to bivalves, and that of various V. tapetis isolates were tested. Inhibition of adherence is detectable with as few as 5 bacteria per hemocyte. The greater cytotoxic activity of V tapetis compared to that of V splendidus and V pectenicida suggests a specific pathogenicity... |
Tipo: Text |
Palavras-chave: Cytotoxicity; Flow cytometry; Vibrio tapetis; Ruditapes philippinarum; Bivalve hemocytes; Pathogenicity. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00000/10761/7590.pdf |
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Aton, Emilie; Renault, Tristan; Gagnaire, Beatrice; Thomas Guyon, Hélène; Cognard, C; Imbert, N. |
Bivalve haemocytes are essential in defence mechanisms including phagocytosis. They also produce molecules including hydrolytic enzymes and antimicrobial peptides that contribute to pathogen destruction. Although haemocyte activities have been extensively studied, relatively little is known about the intracellular signalling pathways that are evoked during haemocyte activation and especially the role of calcium. Flow cytometry has been used for the first time to define the effect of cell incubation in haemolymph and artificial sea water (ASW) on Pacific oyster, Crassostrea gigas, haemocytes. Cell viability, enzymatic activities (esterases and amino peptidases), phagocytosis and granulocyte percentage were analysed. Viability and some activities were... |
Tipo: Text |
Palavras-chave: Cellular activities; Fluo 3/AM; Calcium; Flow cytometry; Haemocytes; Crassostrea gigas. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-935.pdf |
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Le Goic, Nelly; Hegaret, Helene; Fabioux, Caroline; Miner, Philippe; Suquet, Marc; Lambert, Christophe; Soudant, Philippe. |
The toxic dinoflagellate Alexandrium catenella recurrently blooms on the coasts of France and produces Paralytic Shellfish Toxins (PSTs) that accumulate in bivalves. These toxins can affect various physiological functions including reproduction. The present study aims to validate measurements of sperm viability, DNA content and mitochondrial membrane potential in Pacific oyster Crassostrea gigas using flow cytometry coupled with fluorescent markers, and to use these measurements to assess the cellular parameters of sperm from Pacific oysters exposed to A. catenella. These parameters may influence fertilization, embryogenesis and larval development in free-spawning shellfish. Sperm viability and DNA content estimation were assessed using SYBR-14, which only... |
Tipo: Text |
Palavras-chave: Harmful algal bloom; Sperm quality; Cellular parameters; Flow cytometry; Pacific oyster; Crassostrea gigas; Alexandrium catenella. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00157/26853/24982.pdf |
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Marie, Dominique; Rigaut-jalabert, Fabienne; Vaulot, Daniel. |
Preservation of cells, choice of fixative, storage, and thawing conditions are recurrent issues for the analysis of phytoplankton by flow cytometry. We examined the effects of addition of the surfactant Pluronic F68 to glutaraldehyde-fixed photosynthetic organisms in cultures and natural samples. In particular, we examined cell losses and modifications of side scatter (a proxy of cell size) and fluorescence of natural pigments. We found that different marine phytoplankton species react differently to the action of Pluronic F68. In particular, photosynthetic prokaryotes are less sensitive than eukaryotes. Observed cell losses may result from cell lysis or from cell adhesion to the walls of plastic tubes that are commonly used for flow cytometry analysis.... |
Tipo: Text |
Palavras-chave: Phytoplankton; Flow cytometry; Preservation; Pluronic F68; Glutaraldehyde. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00374/48493/48858.pdf |
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Dubief, Bruno; Nunes, Flavia; Basuyaux, Olivier; Paillard, Christine. |
Since 1997, populations of the European abalone Haliotis tuberculata suffer mass mortalities attributed to the bacterium Vibrio harveyi. These mortalities occur at the spawning season, when the abalone immune system is depressed, and when temperatures exceed 17 °C, leading to favorable conditions for V. harveyi proliferation. In order to identify mechanisms of disease resistance, experimental successive infections were carried out on two geographically distinct populations: one that has suffered recurrent mortalities (Saint-Malo) and one that has not been impacted by the disease (Molène). Furthermore, abalone surviving these two successive bacterial challenges and uninfected abalone were used for several post-infection analyses. The Saint-Malo population... |
Tipo: Text |
Palavras-chave: Immunity; Hemocyte; Abalone; Disease; Extracellular products; Immune priming; Vibrio harveyi; Flow cytometry; Resistance; Phagocytosis; Bacterial growth; QPCR; Gill. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00357/46800/46667.pdf |
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Le Goic, Nelly; Hegaret, Helene; Boulais, Myrina; Beguel, Jean-philippe; Lambert, Christophe; Fabioux, Caroline; Soudant, Philippe. |
The Pacific oyster Crassostrea gigas accounts for a large part of shellfish aquaculture production worldwide. Aspects of morphological and functional characteristics of oyster oocytes remain poorly documented, and traditional techniques, such as microscopic observations of shape or fertilization rate, are time and space consuming. The purpose of this study was to assess for the first time viability and reactive oxygen species (ROS) production of Pacific oyster oocytes using flow cytometry (FCM) and to apply this method to determine oocyte responses to in vitro exposure to the toxic dinoflagellate Alexandrium minutum. A culture of A. minutum caused a significant increase in oocyte ROS production, which gradually increased with the age of the culture, but... |
Tipo: Text |
Palavras-chave: Pacific oyster; Gamete quality; ROS production; Viability; Flow cytometry; Ecotoxicology. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00216/32760/31321.pdf |
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Arzul, Isabelle; Bond, Celine; Gagnaire, Beatrice; Morga, Benjamin; Chollet, Bruno; Ferrand, Sylvie; Robert, Maeva; Renault, Tristan. |
Bonamiosis due to the intrahaemocytic protistan parasite Bonamia ostreae is a European endemic disease affecting the flat oyster, Ostrea edulis. After its first description in June 1979ı in Brittany, the parasite rapidly spread to all French oyster farming areas and in other European countries through transfers of live molluscs. The parasite has been described in different ecosystems from estuaries to open sea and no clear correlations could he demonstrated between the disease development and environmental parameters like temperature or salinity. The infection can he directly transmitted by cohabitation between infected and non infected oysters. Nevertheless, the parasite life cycle, including its survival outside the host, is not completely... |
Tipo: Text |
Palavras-chave: Impact; Salinity; Temperature; Flow cytometry; Bonamia ostreae; Parasite; Ostrea edulis; Oyster. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/acte-3372.pdf |
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Robert, Rene; Chretiennot-dinet, Marie-josèphe; Kaas, Raymond; Martin-jezequel, Véronique; Moal, Jeanne; Le Coz, Jean-rene; Nicolas, Jean-louis; Bernard, Eudes; Connan, Jean-paul; Le Dean, Loic; Le Gourrierec, Gaetane; Leroy, Bertrand; Quere, Claudie. |
in mollusc hatcheries. Consequently, we assessed themost commonly used species to establish their growth and size profiles, their cytomorphological, biochemical, biomolecular identification as well as their cytometer signs, and also their ability to grow under extreme conditions of temperature and salinity. This work aimed at matching the conformity of the strains used in Argenton (dispatched to most of the French commercial hatcheries) to those of a referenced culture collection. A previous screening preceded this study, because of the 45 species and/or clones held originally, Argenton kept no more than 15 species. As most of the latter are also represented in referenced collection, our strains are therefore correctly identified. On the other hand, the... |
Tipo: Text |
Palavras-chave: Ecological limits; Biomolecular profile; Flow cytometry; Biochemical composition; Cytomorphology; Phytoplankton; Mollusc; Hatchery; Ecotolérance; Profil biomoléculaire; Cytométrie en flux; Composition biochimique; Cytomorphologie; Phytoplancton; Mollusques; Ecloserie. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/rapport-1546.pdf |
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Stachowski-haberkorn, Sabine; Jerome, Marc; Rouxel, Julien; Khelifi, Celia; Rince, Maeva; Burgeot, Thierry. |
To investigate the ability of microalgae to develop stable, long-term resistance to herbicides, the marine microalga Tetraselmis suecica was exposed to the herbicide diuron (5 µg/L) for a 43-generation exposure period followed by a 12-generation depuration phase. During the first 25 generations, diuron-exposed cultures showed doubling times ranging from 1.95 to 2.6 days, which was 2 to 2.5-fold longer than control cultures. Between generations 25 and 38, during diuron exposure, two out of the three exposed cultures exhibited a spontaneous drop in doubling time. These results provided evidence of culture adaptation to diuron. To assess persistence of the diuron adaptation observed on growth performance, one of the adapted cultures (D3) was maintained for 12... |
Tipo: Text |
Palavras-chave: Microalgae; Diuron; Multigenerational; Adaptation; Flow cytometry. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00146/25718/23796.pdf |
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Lacoste, Elise; Raimbault, Patrick; Harmelin-vivien, Mireille; Gaertner-mazouni, Nabila. |
Bivalve cultures support a host of epibionts, mainly suspension feeders, which can compete for food resources with the cultivated bivalves. However, the magnitude of interspecific competition for food in bivalve aquaculture settings remains inconclusive, especially in tropical areas. We investigated the interactions for food between the farmed pearl oyster Pinctada margaritifera and its epibionts, using stable isotope analysis and feeding experiments. Inter-and intraspecific variations of delta C-13 and delta N-15 stable isotope ratios (SIRs) were determined for oysters in the presence or absence of epibionts. The diet of the most abundant epibionts, Herdmania momus and Didemnum sp., was specified using isotope measurements and flow cytometry during... |
Tipo: Text |
Palavras-chave: Ascidian; Biofouling; Trophic interactions; Stable isotope; Flow cytometry. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00664/77582/79564.pdf |
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Smolarz, Kasia; Renault, Tristan; Soletchnik, Patrick; Wolowicz, Macciek. |
A flow cytometry protocol was applied for the detection of neoplasia in Macoma balthica L. from the Gulf of Gdansk (Baltic Sea, Poland). A simple method, based on an osmotic shock, was used to permeabilise gill cells. The cytometric pattern of normal clams consisted of 2 peaks, a major peak B and a smaller peak C. The cytometric pattern of affected clams consisted of 2 peaks named B' and C'. Two parameters were used to define the stages of abnormalities in M. balthica clams based on the percentage of cells in peaks B, C, B' and C' and on the ratio between the fluorescence value of peaks B, C, B' and C' in all individuals. Three stages of neoplasia were clearly distinguished by flow cytometry considering peak C'. Stage 1 was characterised by a major... |
Tipo: Text |
Palavras-chave: Baltic Sea; Macoma balthica; Neoplasia; Cytogenetics; Histology; Flow cytometry. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-2918.pdf |
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Gagnaire, Beatrice; Soletchnik, Patrick; Faury, Nicole; Kerdudou, Nolwenn; Le Moine, Olivier; Renault, Tristan. |
Internal defence mechanisms of bivalves include the hemocytes which assume several functions. Relationships exist between environmental factors, physiological state of oysters, defence system and pathogens. Hatchery oysters are more and more produced and reared in the field. The characteristics and particularly the defence system of these animals are poorly documented. In this context, two field trials were carried out from May to September 2002 and from April to July 2003 in order to monitor hemocyte parameters of diploid oysters from natural beds and hatchery-produced diploid oysters using flow cytometry. Several hemocyte parameters (cell mortality, granulocyte percentage, phagocytosis, esterase and peroxidase activities) were monitored. For both oyster... |
Tipo: Text |
Palavras-chave: Hatchery; Natural beds; Diploids; Flow cytometry; Peroxidase activity; Esterase activity; Phagocytosis; Hemocytes; Crassostrea gigas; Pacific oyster. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3119.pdf |
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Registros recuperados: 109 | |
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