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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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Labreuche, Yannick; Soudant, Philippe; Goncalves, Madeleine; Lambert, Christophe; Nicolas, Jean-louis. |
Vibrio aestuarianus strain 01/32 was previously shown to be pathogenic to Crassostrea gigas juveniles. To investigate virulence mechanisms of this pathogen, we studied the toxicity to oysters of its extracellular products (ECPs). ECPs displayed lethality to animals, with a LD50 value of 3.3 mu g/g body weight. To determine the oyster cellular immune responses induced by these ECPs, we further examined in vitro their effects on C. gigas hemocytes, using flow cytometric-based hemocyte assays. Treatment of hemolymph with ECPs caused a significant inhibition of hemocyte phagocytosis and adhesive capabilities. In contrast, the pathway of reactive oxygen species production was enhanced by higher ECP concentrations. Exposure of hemocytes to live bacteria induced... |
Tipo: Text |
Palavras-chave: Vibrio aestuarianus; ECPs; Crassostrea gigas; ROS production; Adhesion; Phagocytosis; Flow cytometry; Bivalve immunity. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1035.pdf |
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Boulais, Myrina; Soudant, Philippe; Le Goic, Nelly; Quere, Claudie; Boudry, Pierre; Suquet, Marc. |
Fertilization of the oocyte is a critical process of sexual reproduction depending among other factors on spermatozoa functionality. Mitochondria participate in many crucial processes for spermatozoa motility and fertilizing ability. The Pacific oyster, Crassostrea gigas, is characterized by a high inter-individual variability of its reproductive success which has been shown to be partially due to the variability of gamete quality. The present study explored spermatozoa characteristics such as: i) relationships among mitochondrial functionality (ATP content, mitochondrial membrane potential (MMP), reactive oxygen species production); sperm viability (percentages of live, dying, and dead); and motility; and ii) their involvement in inter-oyster variability... |
Tipo: Text |
Palavras-chave: Spermatozoa; Quality; Motility; Viability; ATP content; ROS production. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00386/49769/50309.pdf |
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Seguineau, Catherine; Racotta, Ilie; Palacios, Elena; Delaporte, Maryse; Moal, Jeanne; Soudant, Philippe. |
In a previous study, dietary supplementation with arachidonic acid (ARA) to oysters Crassostrea gigas increased haemocyte numbers, phagocytosis, and production of reactive oxygen species level (ROS) by haemocytes (Delaporte et al., 2006). To assess if the observed stimulation of these cellular responses resulted from changes of ARA-related prostaglandin (PG) production, we analysed prostaglandin E2 metabolite (PGEM) content on the same oysters fed three levels of ARA. Dietary supply of polyunsaturated fatty acids (PUFA) could also induce an oxidative stress that could similarly increase cellular responses; therefore, two indicators of oxidative stress were analysed: peroxidation level and antioxidant defence status. Together the observed positive... |
Tipo: Text |
Palavras-chave: Prostaglandins; N-6 unsaturated fatty acids; Lipid peroxidation; Antioxidants; ROS production. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00040/15103/12785.pdf |
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Rivera-ingraham, Georgina A.; Barri, Kiam; Boel, Melanie; Farcy, Emilie; Charles, Anne-laure; Geny, Bernard; Lignot, Jehan-herve. |
Osmoregulating decapods such as the Mediterranean green crab Carcinus aestuarii possess two groups of spatially segregated gills: anterior gills serve mainly respiratory purposes, while posterior gills contain osmoregulatory structures. The co-existence of similar tissues serving different functions allows the study of differential adaptation, in terms of free radical metabolism, upon salinity change. Crabs were immersed for 2 weeks in seawater (SW, 37 ppt), diluted SW (dSW, 10 ppt) and concentrated SW (cSW, 45 ppt). Exposure to dSW was the most challenging condition, elevating respiration rates of whole animals and free radical formation in hemolymph (assessed fluorometrically using C-H(2)DFFDA). Further analyses considered anterior and posterior gills... |
Tipo: Text |
Palavras-chave: Antioxidant defense; Carcinus aestuarii; ROS production; Osmoregulation. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00626/73816/74410.pdf |
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