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| Registros recuperados: 48 | |
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| Medhioub, Walid; Sechet, Veronique; Truquet, Philippe; Bardouil, Michele; Amzil, Zouher; Lassus, Patrick; Soudant, Philippe. |
| Growth and spirolide production of the toxic dinoflagellate Alexandrium ostenfeldii (Danish strain CCMP1773) were studied in batch culture and a photobioreactor (continuous cultures). First, batch cultures were grown in 450 mL flasks without aeration and under varying conditions of temperature (16 and 22 degrees C) and culture medium (L1, f/2 and L1 with addition of soil extract). Second, cultures were grown at 16 degrees C in 8 L aerated flat-bottomed vessels using L1 with soil extract as culture medium. Finally, continuous cultures in a photobioreactor were conducted at 18 degrees C in L1 with soil extract; pH was maintained at 8.5 and continuous stirring was applied. This study showed that A. ostenfeldii growth was significantly affected by temperature.... |
| Tipo: Text |
Palavras-chave: Alexandrium ostenfeldii; Batch; Growth; Photobioreactor; Spirolide production. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00049/16050/15784.pdf |
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| Jauffrais, Thierry; Marcaillou-le Baut, Claire; Herrenknecht, Christine; Truquet, Philippe; Sechet, Veronique; Nicolau, Elodie; Tillmann, Urban; Hess, Philipp. |
| Azadinium spinosum (Elbrächter and Tillmann), a small marine dinoflagellate, has been recently described as a de novo producer of azaspiracid-1 and -2 (AZA1 and -2) diarrhoeic toxins. A culture of A. spinosum was established in our laboratory and optimised for pilot-scale production of this organism, to evaluate and understand AZA1 and -2 accumulation and biotransformation in blue mussels (Mytilus edulis) fed with A. spinosum. Adult mussels were continuously exposed to A. spinosum over 1 week in 160 L cylindrical conical tanks. Three different diets were tested for contamination: 5000, 10 000 cells mL−1 of A. spinosum and a mixture of 5000 cells mL−1 of A. spinosum with 5000 cells mL−1 of Isochrysis aff. galbana (T-Iso, CCAP 927/14). During the subsequent... |
| Tipo: Text |
Palavras-chave: Azaspiracid; Azadinium spinosum; Marine biotoxins; AZA; Tissue distribution; Histology; Bivalve molluscs; Liquid chromatography coupled to tandem mass spectrometry. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00088/19877/17566.pdf |
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| Baron, Regis; Couedel, Marielle; Joret, Camille; Garen, Pierre; Truquet, Philippe; Masselin, Pierre; Bardouil, Michele; Lassus, Patrick. |
| A simple system was used to simulate the effect of alternating toxic (paralytic shellfish poisoning toxins) and non-toxic microalgal diets on oyster feeding behaviors and rates of toxin accumulation. These experimental conditions were meant to reflect, to some extent, the incoming and outgoing fluxes of toxic algae observed at the mouth of the Penze estuary (Northern Brittany, France). Physiological and toxicological parameters were estimated based oil fluorescence measurements recorded continuously at the outlet of each experimental tank, which contained a single oyster. Q(tox), this variable describes toxin uptake in oysters, it was used (instead of the toxin ingestion rate): i) in simple graphical analyses, ii) as well as in one- and two-compartment... |
| Tipo: Text |
Palavras-chave: Skeletonema costatum; Alexandrium minutum; Fluorescence; Modeling; Kinetics; Toxin uptake; Shellfish toxin; PSP. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1400.pdf |
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| Lassus, Patrick; Bardouil, Michele; Masselin, Pierre; Naviner, Magali; Truquet, Philippe. |
| A sea water recirculating flume was especially designed in the framework of this study. It improves physiological and ecophysiological evaluation of a 25 oysters (c. gigas) set fed on PSP toxic A. minutum cultures and then detoxified with commonly used aquaculture species (I. galbana, T. suecica, S. costatum, T. weissflogii). Chlorophyll a levels are kept steady in each case and adjusted in order to reach the same food value in each tank (0,5 mg/l TPM). When exposed to the mildly toxic species A. minutum (0,5 pg.eq.STX.cel-1) oysters depict a reduced clearance rate, food uptake and shell-valves activity (compared to non-toxic algal diets). The same physiological parameters do not show any significant differences when oysters are exposed to the control al... |
| Tipo: Text |
Palavras-chave: Épuration; Crassostrea gigas; Alexandrium minutum; PSP; Écophysiologie; Depuration; C. gigas; A. minutum; PSP; Ecophysiology. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00139/25021/23126.pdf |
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| Marcaillou-le Baut, Claire; Masselin, Pierre; Bohec, Madeleine; Truquet, Philippe; Amzil, Zouher; Pouchus, Francois; Le Boterff, Jean; Verbist, Jean-françois; Vernoux, Jean-paul; Marais, Chantal; Simon, Jean-françois; Nizard, Gabrielle; Mercier, Géraldine; Choumiloff, Roxelan; Baron, Bruno. |
| Cette étude est le résultat d'un travail de trois équipes: elle porte sur la comparaison du test souris avec différents bioessais déjà pratiqués en routine dans les laboratoires participants. Ces bioessais sont : - un test sur micro crustacé dont la méthodologie est normalisée et qui est très utilisé en écotoxicologie aquatique ; - un test de cytotoxicité à court terme qui a été mis au point pour cette étude. |
| Tipo: Text |
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| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00139/25035/23144.pdf |
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| Medhioub, Walid; Gueguen, Marielle; Lassus, Patrick; Bardouil, Michele; Truquet, Philippe; Sibat, Manoella; Nejib, Medhioub; Philippe, Soudant; Mejdeddine, Kraiem; Amzil, Zouher. |
| In the Gulf of Gabes (Tunisia, Eastern Mediterranean sea), the grooved carpet shell Ruditapes decussatus has been seen to contain persistent levels of gymnodimine (GYM) for several years. The present experimental work represents the first attempt to assess detoxification kinetics of fast-acting toxins (FAT) in marine molluscs fed specific diets of non-toxic algae (Isochrysis galbana). To find an optimal detoxification method, two experiments were performed in which clams were first fed the toxic dinoflagellate Karenia selliformis to artificially contaminate them with GYM, thus simulating the effect of natural toxic episodes. As a second step, the same clams were fed a non-toxic algae, I. galbana. to speed up the detoxification process. Changes in toxin... |
| Tipo: Text |
Palavras-chave: Ruditapes decussates; Grooved carpet shell; Karenia selliformis; Gymnodimine; Toxicity; Detoxification. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/2010/publication-7488.pdf |
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| Gueguen, Marielle; Bardouil, Michele; Baron, Regis; Lassus, Patrick; Truquet, Philippe; Massardier, Julie; Amzil, Zouher. |
| Contamination of shellfish by paralytic shellfish poisoning ( PSP) toxins poses an economic threat to shellfish farmers. As contaminated shellfish cannot be harvested for long periods of time, it would be very useful to develop processes to optimise and shorten their detoxification. In this study, Pacific oysters Crassostrea gigas were first experimentally contaminated over a period of 13 days with a continuous flow of toxic Alexandrium minutum cultures at concentrations ranging from 150 to 200 cell ml(-1) ( toxin content after 13 days of contamination 438 mu g STX equiv. 100 g(-1) wet weight). Then, two different detoxification treatments were tested and showed detoxification rates greater than those observed in coastal environments. The first treatment... |
| Tipo: Text |
Palavras-chave: Alexandrium minutum; Crassostrea gigas; Detoxification; Inorganic matter; Organic matter; PSP; Paralytic shellfish poisoning. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3896.pdf |
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| Jauffrais, Thierry; Kilcoyne, Jane; Herrenknecht, Christine; Truquet, Philippe; Sechet, Veronique; Miles, Christopher O.; Hess, Philipp. |
| The relationship between azaspiracid shellfish poisoning and a small dinoflagellate, Azadinium spinosum, has been shown recently. The organism produces AZA1 and -2, while AZA3 and other analogues are metabolic products formed in shellfish. We evaluated whether mussels were capable of accumulating dissolved AZA1 and -2, and compared the toxin profiles of these mussels at 24 h with profiles of those exposed to live or lysed A. spinosum. We also assessed the possibility of preparative production of AZA metabolites by exposing mussels to semi-purified AZA1. We exposed mussels to similar concentration of AZAs: dissolved AZA1+2 (crude extract) at 7.5 and 0.75 µg L-1, dissolved AZA1+2 (7.5 µg L-1) in combination with Isochrysis affinis galbana, and lysed and live... |
| Tipo: Text |
Palavras-chave: Dissolved marine biotoxins; AZA; Tissue distribution; Bivalve molluscs; LC-MS/MS; Azaspiracid. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00136/24757/22867.pdf |
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| Maggi, Pierre; Truquet, Philippe; Mornet, Francoise; Lassus, Patrick. |
| Une campagne de prélèvements hydrologiques a été réalisée en juillet 1991 en baie de Seine sur le N/O THALIA. Elle visait à connaître la distribution du phytoplancton en fonction des paramètres physicochimiques du milieu et plus particulièrement par rapport à l'extension du panache de la Seine. Bien que les espèces toxiques recherchées (Dinophysis spp.) aient été absentes au cours de cette opération, l'analyse et le traitement des données recueillies sur une radiale côtière située entre le Havre et Antifer ont permis de discriminer les espèces à affinité estuarienne ou marine présentes pendant cette période. Les diatomées étaient largement dominantes, en particulier Skeletonema costatum et Rhizosolenia stolterfothii, alors que les dinoflagellés étaient... |
| Tipo: Text |
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| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00064/17535/15053.pdf |
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| Lassus, Patrick; Maggi, Pierre; Proniewski, F.; Truquet, Philippe; Nizard, G.. |
| Time-related Dinophysis spp vertical profiles have been studyed during a 48 hours cycle in a submerged cylindric tank. A coïncidental Gymnodinium sp. (Scrippsiella trochoidea and Prorocentrum triestinum as companion species) red tide was believed to have strong effect on Dinophysis distribution in the upper layer during the tirst 24 hours cycle of the period of investigation (August 30-31, 1991). Between 24 and 48 hours, the sharp decrease of Dinophysis densities as well as the graduai decline observed in the red tide and in the vertical thermal gradient have resulted in a migration of dominant species : D. sacculus and D. cf. acuminata toward subsuperficiallevels (5 to 7 m.d) with a higher range in cells vertical movements. This behavior is very similar... |
| Tipo: Text |
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| Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/00138/24948/23041.pdf |
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| Jauffrais, Thierry; Contreras, Andrea; Herrenknecht, Christine; Truquet, Philippe; Sechet, Veronique; Tillmann, Urban; Hess, Philipp. |
| Azadinium spinosum, a small toxic dinoflagellate, was recently isolated and identified as a primary producer of azaspiracid toxins (AZAs). Previous experiments related to AZA accumulation in blue mussels upon direct feeding with A. spinosum revealed increased mussel mortality and had negative effects on the thickness of the digestive gland tubules. Therefore we conducted follow up experiments in order to study effects of A. spinosum on mussel feeding behaviour. Individual assessment of mussel feeding time activity (FTA), clearance rate (CR), filtration rate (TFR), absorption rate (AR), faeces and pseudofaeces production were carried out on mussel fed either toxic (A. spinosum) or non-toxic (Isochrisis aff. galbana (T-Iso)) diets. Furthermore, AZA... |
| Tipo: Text |
Palavras-chave: Bivalve molluscs; Mussel; Ecophysiology; AZA biotransformation; AZA accumulation; Trophic transfer; Dinoflagellate; Azaspiracid. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00090/20174/17832.pdf |
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| Jauffrais, Thierry; Sechet, Veronique; Truquet, Philippe; Amzil, Zouher; Herrenknecht, Christine; Hess, Philipp. |
| Azadinium spinosum, a small dinoflagellate has recently been discovered and identified as the primary producer of azaspiracid-1 (AZA) and -2. Since AZA poisoning has been reported following consumption of contaminated shellfish it is important to have these toxins available for toxicological studies, and a sustainable production of AZAs as calibrants in monitoring programs without having to rely on natural events. In order to address this concern, continuous pilot scale cultures were carried out to evaluate the feasibility of AZA production from A. spinosum. Algae were cultured using two 100 L chemostats in series (R1 and R2), with agitation and pH control. Four different dilution rates were tested (0.15, 0.2, 0.25 and 0.3 day−1) to evaluate chemostat... |
| Tipo: Text |
Palavras-chave: Solid phase adsorption; Chemostat; Photobioreactor; Microalgae; LC-MS/MS; Tangential flow filtration. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00152/26349/24437.pdf |
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| Jauffrais, Thierry; Sechet, Veronique; Herrenknecht, Christine; Truquet, Philippe; Savar, Veronique; Tillmann, Urban; Hess, Philipp. |
| Azadinium spinosum, a small dinoflagellate isolated from the North Sea, is a producer of azaspiracids (AZAs), a group of biotoxins associated with human illness following ingestion of contaminated shellfish. Using batch and continuous cultures of A. spinosum, the present study investigated the effects of different environmental and nutritional factors (salinity, temperature, photon flux density, aeration, culture media, nitrogen sources, phosphate source, and N/P ratios) on growth, maximum cell concentration, and AZA cell quota. Azadinium spinosum grew in a wide range of conditions; from 10 ̊C to 26 ̊C and salinities from 30 to 40, under irradiances ranging from 50 μmol m−2 s−1 to 250 μmol m−2 s−1, with or without aeration. Growth and maximum cell... |
| Tipo: Text |
Palavras-chave: AZA; Chemostat; Dinophyceae; Nutrients; N/P ratio; Photobioreactor. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00149/26054/24411.pdf |
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| Marcaillou-le Baut, Claire; Bardin, B.; Bardouil, Michele; Bohec, Madeleine; Le Dean, Loic; Masselin, Pierre; Truquet, Philippe. |
| Two studies of depuration, one in laboratory conditions and the other one in an oyster's pond were performed using 2 sets of contaminated mussels with diarrhetic toxins at a high and a low level (3 and 1 M.U.). Depuration kinetics were followed both by the adult mouse test and okadaïc acid analysis. Results are - in the pond, high toxic mussels need about 20 days to become eatable (toxicity level : 0.5 M.U.g-1 digestive glands), -this time decreases when the initial toxicity is low but it increases when mussels are underfed, - a good correlation is observed between the total toxicity and okadaïc acid concentration. |
| Tipo: Text |
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| Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/00075/18595/16148.pdf |
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| Marcaillou Le Baut, C; Bardouil, Michele; Bocquene, Gilles; Le Dean, Loic; Truquet, Philippe. |
| This work is the preliminary synthesis of some toxicological tests conducted on three pesticides. This recapitulation would not have been possible without the contribution of our trainees, Misses V. Perles and H. Le Boulicot and MM. M. Falchier and G. Gaty who contributed largely to this study, supervised by the laboratory staff. The obtained results cannot be considered as definitive. The urge to answer the needs did not leave us enough time to fine tune and/or complete the results; for example we still have not determined the lethal dose for 50% of the individuals. [...] |
| Tipo: Text |
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| Ano: 1983 |
URL: https://archimer.ifremer.fr/doc/1983/rapport-4575.pdf |
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| Bardouil, Michele; Bohec, Madeleine; Bougrier, Serge; Lassus, Patrick; Truquet, Philippe. |
| An experimental flow-through system allowing determination of the feeding behaviour of individual molluscs was used to study oysters exposed to mixed diets composed of varying proportions of the diatom Thalassiosira weissflogii and two strains (toxic and nontoxic) of the dinoflagellate Alexandrium larnarense. Our results show that, when compared to a T. weissflogii unialgal diet, even a diatomltoxic dinoflagellate ratio as low in biomass as 90/10 reduced clearance rates and biodeposit production by oysters. Consumption was slightly but significantly decreased for a 50/50 diatomltoxic dinoflagellate mixture. For the toxic dinoflagellate unialgal diet, ingestion, absorption and consumption were completely inhibited. Thus, the inclusion of low amounts of... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Thalassiosira weissflogii; Alexandrium tamarense; Ecophysiologie; Toxine paralysante des coquillages; Crassostrea gigas; Thalassiosira weissflogii; Alexandrium tamarense; Ecophysiology; Paralytic shellfish poison. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00017/12788/9729.pdf |
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| Registros recuperados: 48 | |
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