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Registros recuperados: 35 | |
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Akcha, Farida. |
In the aim to develop biomarkers of genotoxicity for the biomonitoring of the marine environment,the formation of DNA adducts and oxidized DNA bases was studied for the sentinel organism, Mytilus sp, following exposure to B[a]P via the trophic supply. DNA adducts and 8-oxo-7,8-dihydro-2'-désoxyguanosine (8-oxodGuo) were respectively measured by 32P post-labeling technique and high performance liquid chromatography coupled to electrochemical detection. The developped model of exposure was validated for the realisation of toxicological studies in Mytilus sp. The bioavailability of B[a]P for the exposed organisms and its biotransformation resulted in variations in most of the measured enzymatic biomarkers of exposure. Such an exposure allowed the expression... |
Tipo: Text |
Palavras-chave: Moule; B[a]P; Adduits; 8-oxodGuo; Biomarqueurs; Mussel; B[a]P; Adducts; 8-oxodGuo; Biomarkers. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00076/18770/16349.pdf |
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Akcha, Farida; Arzul, Genevieve; Rousseau, Sabrina; Bardouil, Michele. |
The alkaline comet assay was tested on different microalgae: the clinofiagellates, Karenia mikimotoi and Alexandrium minuturn, and the diatom, Chaetoceros gracilis. The microalgae were exposed during their exponential growth to the model direct genotoxicant, hydrogen peroxide (1 h, 5 and 100 pM H2O2). Following H2O2 exposure, the comet assay was validated only for K. mikimotoi for which genotoxicity was observed from the lowest tested concentration of 5 pM with a concentration-dependent effect. C. gracilis was too small in size (4 mu m) to be correctly analysed. For A. minuturn, our lysis buffer was not strong enough to digest the cellulosic thecal plates. For K. mikimotoi, the comet assay was thus applied for the study of the genotoxic effects of... |
Tipo: Text |
Palavras-chave: Comet assay; Genotoxicity; Pesticides; Phytoplankton. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4504.pdf |
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Akcha, Farida; Barranger, Audrey; Bachere, Evelyne; Berthelin, C. Heude; Piquemal, D.; Alonso, P.; Sallan, R. Rondon; Dimastrogiovanni, G.; Porte, C.; Menard, Dominique; Szczybelski, A.; Benabdelmouna, Abdellah; Auffret, M.; Rouxel, Julien; Burgeot, Thierry. |
Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation... |
Tipo: Text |
Palavras-chave: Oyster; Pesticide; Reproduction; Histology; Gene expression; RT-qPCR; Steroid; Immunity. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00309/41983/83232.pdf |
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Akcha, Farida; Burgeot, Thierry; Budzinski, H; Pfohla Leszkowicz, A; Narbonne, J. |
With the aim of developing biomarkers of polycyclic aromatic hydrocarbon (PAH) genotoxicity for biomonitoring of the marine environment, the formation of DNA adducts and oxidative DNA damage was studied in the sentinel organism Mytilus. Mussels M. galloprovincialis were exposed for 21 d to different doses of benzo[a]pyrene (B[a]P) (50 and 100 mg B[a]P kg(-1) dry wt mussel d(-1)) via trophic intake. The kinetics of B[a]P concentration in whole mussel tissues was determined in both groups, and a dose-response study was conducted for both gill B[a]P-related DNA adducts and 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodGuo) formation in gill and digestive gland DNA. Exposure was followed by a 10 d depuration period to study mussel recovery. Although B[a]P was... |
Tipo: Text |
Palavras-chave: DNA repair; 8 oxodGuo; DNA adducts; Mussel; BaP. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-813.pdf |
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Akcha, Farida; Spagnol, Charlene; Rouxel, Julien. |
We investigated the effects of genotoxicant exposure in gametes and embryos to find a possible link between genotoxicity and reproduction/developmental impairment, and explore the impact of chemical genotoxicity on population dynamics. Our study focused on the genotoxic effects of two herbicides on oyster gametes and embryos: glyphosate (both as an active substance and in the Roundup formulation) and diuron. France is Europe's leading consumer of agrochemical substances and as such, contamination of France's coastal waters by pesticides is a major concern. Glyphosate and diuron are among the most frequently detected herbicides in oyster production areas; as oyster is a specie with external reproduction, its gametes and embryos are in direct contact with... |
Tipo: Text |
Palavras-chave: Genotoxicity; Embryotoxicity; Oyster; Gametes; Pesticides; Diuron; Glyphosate. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00070/18128/15783.pdf |
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Barranger, Audrey; Akcha, Farida; Rouxel, Julien; Brizard, Raphael; Maurouard, Elise; Pallud, Marie; Menard, Dominique; Tapie, N.; Budzinski, Helene; Burgeot, Thierry; Benabdelmouna, Abdellah. |
Pesticides represent a major proportion of the chemical pollutants detected in French coastal waters and hence a significant environmental risk with regards to marine organisms. Commercially-raised bivalves are particularly exposed to pollutants, among them pesticides, as shellfish farming zones are subject to considerable pressure from agricultural activities on the mainland. The aims of this study were to determine (1) the genotoxic effects of diuron exposure on oyster genitors and (2) the possible transmission of damaged DNA to offspring and its repercussions on oyster fitness. To investigate these points, oysters were exposed to concentrations of diuron close to those detected in the Marennes-Oleron Basin (two 7-day exposure pulses at 0.4 and 0.6 μg... |
Tipo: Text |
Palavras-chave: Herbicide; Diuron; Oyster; Genotoxicity; Comet assay; Cytogenetics. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00162/27311/25541.pdf |
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Barranger, Audrey; Benabdelmouna, Abdellah; Degremont, Lionel; Burgeot, Thierry; Akcha, Farida. |
Changes in normal chromosome numbers (i.e. aneuploidy) due to abnormal chromosome segregation may arise either spontaneously or as a result of chemical/radiation exposure, particularly during cell division. Coastal ecosystems are continuously subjected to various contaminants originating from urban, industrial and agricultural activities. Genotoxicity is common to several families of major environmental pollutants, including pesticides, which therefore represent a potential important environmental hazard for marine organisms. A previous study demonstrated the vertical transmission of DNA damage by subjecting oyster genitors to short-term exposure to the herbicide diuron at environmental concentrations during gametogenesis. In this paper, Fluorescent in... |
Tipo: Text |
Palavras-chave: Aneuploidy; FISH; Diuron; Crassostrea gigas. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00238/34911/33216.pdf |
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Barranger, Audrey; Langan, Laura M.; Sharma, Vikram; Rance, Graham A.; Aminot, Yann; Weston, Nicola J.; Akcha, Farida; Moore, Michael N.; Arlt, Volker M.; Khlobystov, Andrei N.; Readman, James W.; Jha, Awadhesh N.. |
This study aimed to assess the ecotoxicological effects of the interaction of fullerene (C60) and benzo[a]pyrene (B[a]P) on the marine mussel, Mytilus galloprovincialis. The uptake of nC60, B[a]P and mixtures of nC60 and B[a]P into tissues was confirmed by Gas Chromatography–Mass Spectrometry (GC–MS), Liquid Chromatography–High Resolution Mass Spectrometry (LC–HRMS) and Inductively Coupled Plasma Mass Spectrometer (ICP–MS). Biomarkers of DNA damage as well as proteomics analysis were applied to unravel the interactive effect of B[a]P and C60. Antagonistic responses were observed at the genotoxic and proteomic level. Differentially expressed proteins (DEPs) were only identified in the B[a]P single exposure and the B[a]P mixture exposure groups containing 1... |
Tipo: Text |
Palavras-chave: Trojan horse effect; B[a]P; NC(60); Co-exposure; Mussels; DNA damage; Proteomics. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00506/61780/65779.pdf |
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Barranger, Audrey; Langan, Laura M; Sharma, Vikram; Rance, Graham A; Aminot, Yann; Weston, Nicola J; Akcha, Farida; Moore, Michael N; Arlt, Volker M; Kholbystov, Andrei N; Readman, James W; Jha, Awadhesh N.. |
This study aimed to assess the ecotoxicological effects of the interaction of fullerene (C60) and benzo[a]pyrene (B[a]P) on the marine mussel, Mytilus galloprovincialis. The uptake of nC60, B[a]P and mixtures of nC60 and B[a]P into tissues was confirmed by GC-MS, LC-HRMS and ICP-MS. Biomarkers of DNA damage as well as proteomics analysis were applied to unravel the toxic effect of B[a]P and C60. Antagonistic responses were observed at the genotoxic and proteomic level. Differentially expressed proteins (DEPs) were only identified in the B[a]P single exposure and the B[a]P mixture exposure groups containing 1 mg/L of C60, the majority of which were down-regulated (~52%). No DEPs were identified at any of the concentrations of nC60 (p < 0.05, 1% FDR).... |
Tipo: Text |
Palavras-chave: Trojan Horse effect; B[a]P; NC60; Co-exposure; Mussels; DNA damage; Proteomics. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00498/60946/64340.pdf |
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Bean, Tp; Akcha, Farida. |
Single cell gel electrophoresis (SCGE or comet) assay allows quantification of DNA damage in individual cells and is an ideal tool for use within biological monitoring programmes. Comet assay can be used on a range of cell types including somatic, reproductive (gametes) or circulatory cells in many different species including both marine bivalves and flatfish. The assay can be employed with simple equipment available in most laboratories, is sensitive to environmentally relevant levels of DNA damage (Frenzilli and Lyons, 2009), accurately demonstrates a linear dose response to exposure (Collins et al., 1996), and can be adapted for use on most nucleated cell types. This document concentrates on the simplest and most repeatable method of comet assay in... |
Tipo: Text |
Palavras-chave: Comet assay; Single cell gel electrophoresis; DNA damage; Genotoxicity; Biological effects; Bivalves; Flatfish; Integrated monitoring. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00587/69902/67807.pdf |
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Behrens, Daphne; Rouxel, Julien; Burgeot, Thierry; Akcha, Farida. |
Herbicides are one of the major classes of pollutants contaminating coastal waters over the world. Among them, diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a phenylurea herbicide frequently detected in oyster-producing area, known to be toxic for this important exploited non-target species. With the aim to investigate the mechanisms by which diuron displays its toxicity in oyster, the implication of both biotransformation and oxygen reactive species (ROS) production was studied considering embryotoxicity and genotoxicity as endpoints. Comparative embryotoxicity and genotoxicity of diuron and its main metabolites (DCPMU, DCPU and 3,4-DCA) were thus studied on oyster larvae by the embryo-larval bioassay on D larvae and the comet assay on trochophore... |
Tipo: Text |
Palavras-chave: Oyster; Herbicide; Embryotoxicity; Genotoxicity; Oxidative stress; Biotransformation. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00324/43521/43053.pdf |
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Buchet, Vincent; Akcha, Farida; Stachowski-haberkorn, Sabine. |
Il s’agissait i) de mettre en place un réseau de suivi de la qualité de l’eau, ii) de déterminer la qualité de chaque élevage larvaire dans le but de mettre en évidence un lien éventuel entre la qualité physico-chimique de l’eau de mer et la production conchylicole en écloserie, iii) mettre en évidence, l'influence de l’eau utilisée pour l’élevage, à court-terme, sur la « qualité » physiologique de l’algue fourrage T-iso utilisée pour nourrir les larves et à plus long-terme vérifier si ses capacités de croissance ainsi que sa «qualité» physiologique sont susceptibles d’être modifiées en fonction de la qualité de l’eau issue du polder. Les résultats obtenus ont mis en évidence la présence permanente de contaminants chimiques dans les eaux du polder. Les... |
Tipo: Text |
Palavras-chave: Contaminants chimiques; Huîtres; Écloserie; Polder ostréicole; T iso. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00477/58885/62812.pdf |
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Burgeot, Thierry; Akcha, Farida; Menard, Dominique; Robinson, Craig; Loizeau, Veronique; Brach-papa, Christophe; Martinez-gomez, Concepcion; Le Goff, Jeremie; Budzinski, Helene; Le Menach, Karine; Cachot, Jerome; Minier, Christophe; Broeg, Katja; Hylland, Ketil. |
The International workshop on Integrated Assessment of CONtaminants impacts on the North sea (ICON) provided a framework to validate the application of chemical and biological interpretation thresholds (BACs and EACs) in the Seine Bay in France. Bioassays (oyster larval anomalies, Corophium arenarium toxicity assay and DR Calux) for sediment and biomarkers: ethoxyresorufin-O-deethylase (EROD) activity, acetylcholinesterase (AChE) activity, lysosomal membrane stability (LMS), DNA strand breaks using the comet assay, DNA adducts, micronucleus (MN), PAH metabolites, intersex and fish external pathologies were analyzed in four marine sentinel species (Platichthys flesus, Limanda limanda, Mytilus sp. and Nucella lapilus). Polycyclic aromatic hydrocarbons... |
Tipo: Text |
Palavras-chave: Biomarkers; Bioassays; Chemical contamination; Integrated monitoring in chemistry and biology; Local study; Large geographical scale. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00357/46789/46655.pdf |
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Cheray, Mathilde; Etcheverry, Amandine; Jacques, Camille; Pacaud, Romain; Bougras-cartron, Gwenola; Aubry, Marc; Denoual, Florent; Peterlongo, Pierre; Nadaradjane, Arulraj; Briand, Josephine; Akcha, Farida; Heymann, Dominique; Vallette, François M.; Mosser, Jean; Ory, Benjamin; Cartron, Pierre-françois. |
Background Literature reports that mature microRNA (miRNA) can be methylated at adenosine, guanosine and cytosine. However, the molecular mechanisms involved in cytosine methylation of miRNAs have not yet been fully elucidated. Here we investigated the biological role and underlying mechanism of cytosine methylation in miRNAs in glioblastoma multiforme (GBM). Methods RNA immunoprecipitation with the anti-5methylcytosine (5mC) antibody followed by Array, ELISA, dot blot, incorporation of a radio-labelled methyl group in miRNA, and miRNA bisulfite sequencing were perfomred to detect the cytosine methylation in mature miRNA. Cross-Linking immunoprecipiation qPCR, transfection with methylation/unmethylated mimic miRNA, luciferase promoter reporter plasmid,... |
Tipo: Text |
Palavras-chave: MiRNA; Cytosine-methylation; Epigenetics; DNMT3A; AGO4; Glioblastoma; Epitranscriptomics. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00610/72196/70980.pdf |
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Claireaux, Guy; Desaunay, Yves; Akcha, Farida; Auperin, Benoît; Bocquene, Gilles; Budzinski, Hélène; Cravedi, Jean-pierre; Davoodi, Fariba; Galois, Robert; Gilliers, Camille; Goanvec, Christelle; Guerault, Daniel; Imbert, Nathalie; Mazeas, Olivier; Nonnotte, Guy; Nonnotte, Liliane; Prunet, Patrick; Sebert, Philippe; Vettier, Aurélie. |
Evaluating the ecological impact of an oil spill is a complex issue requiring coherently articulated examination of the sequence of interactions that link the cell, where contaminants exert their effects, to the ecosystem, where interactions with human activities arise. This sequence of interactions traverses the frontiers between scientific disciplines (chemistry, toxicology, physiology, and fisheries ecology). Using the common sole (Solea solea L.) as a model species for the coastal habitats polluted by the "Erika" oil spill, our research project attempted to define indices of functional integrity that characterised the consequences of fuel exposure at the different biological levels. The coupling of field observations with experimental laboratory work... |
Tipo: Text |
Palavras-chave: Physiological ecology; Common sole; Complex system approach; Oil spill. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-405.pdf |
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Dupraz, Valentin; Ménard, Dominique; Akcha, Farida; Budzinski, Hélène; Stachowski-haberkorn, Sabine. |
This study screened binary mixtures of pesticides for potential synergistic interaction effects on growth of the marine microalgae Tisochrysis lutea and Skeletonema marinoi. It also examined the single and combined effects of three of the most toxic substances on microalgal physiology. Single substances were first tested on each microalgal species to determine their respective EC50 and concentration-response relationships. The toxicity of six and seven binary mixtures was then evaluated in microplate experiments on the growth of T. lutea and S. marinoi, respectively, using two mixture modelling approaches: isobolograms and the MIXTOX tool, based on Concentration Addition (CA) or Independent Action (IA) models. Significant cases of antagonism (for both... |
Tipo: Text |
Palavras-chave: ROS; Photosynthesis; Lipids; Synergy; Isoproturon; Metazachlor. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00488/59928/63131.pdf |
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Dupraz, Valentin; Stachowski-haberkorn, Sabine; Menard, Dominique; Limon, Gwendolina; Akcha, Farida; Budzinski, Helene; Cedergreen, Nina. |
The toxicity of the antifouling compounds diuron, irgarol, zinc pyrithione (ZnPT), copper pyrithione (CuPT) and copper was tested on the three marine microalgae Tisochrysis lutea, Skeletonema marinoi and Tetraselmis suecica. Toxicity tests based on the inhibition of growth rate after 96-h exposure were run using microplates. Chemical analyses were performed to validate the exposure concentrations and the stability of the compounds under test conditions. Single chemicals exhibited varying toxicity depending on the species, irgarol being the most toxic chemical and Cu the least toxic. Selected binary mixtures were tested and the resulting interactions were analyzed using two distinct concentration-response surface models: one using the concentration addition... |
Tipo: Text |
Palavras-chave: Diuron; Irgarol; Pyrithione; Copper; Microbial ecotoxicology; Mixture model. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00445/55695/57362.pdf |
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Dupraz, Valentin; Stachowski-haberkorn, Sabine; Wicquart, Jérémy; Tapie, Nathalie; Budzinski, Hélène; Akcha, Farida. |
Pesticides used in viticulture create a potential risk for the aquatic environment due to drift during application, runoff and soil leaching. The toxicity of sixteen pesticides and one metabolite were evaluated on the growth of two marine microalgae, Tisochrysis lutea and Skeletonema marinoi, in 96-h exposure assays conducted in microplates. For each substance, concentrations of stock solutions were analytically measured and abiotic assays were performed to evaluate the chemical stability of pesticides in microplates. For two chemicals, microalgae exposures were run simultaneously in microplates and culture flasks to compare EC50 calculated from the two exposure systems. Results from chemical analyses demonstrated the low stability of hydrophobic... |
Tipo: Text |
Palavras-chave: Microalgae; Microplates; Screening; Pesticides; Toxicity; Exposure characterisation. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00474/58558/61113.pdf |
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Kammann, U.; Akcha, Farida; Budzinski, H.; Burgeot, Thierry; Gubbins, M. J.; Lang, T.; Le Menach, K.; Vethaak, A. D.; Hylland, K.. |
Polycyclic aromatic hydrocarbons (PAH) are environmental contaminants that pose significant risk to health of fish. The International Workshop on Integrated Assessment of Contaminant Impacts on the North Sea (ICON) provided the framework to investigate biomarker responses as well as contaminant concentrations side by side in marine ecosystems. Concentrations of the main PAH metabolites 1-hydroxypyrene, 1-hydroxyphenanthren and 3-hydroxybenzo(a)pyrene were determined in bile by HPLC with fluorescence detection. Fish species under investigation were dab (Limanda limanda), flounder (Platichthys flesus) and haddock (Melanogrammus aeglefinus). A contamination gradient was demonstrated from the low contaminated waters of Iceland and off-shore regions of the... |
Tipo: Text |
Palavras-chave: PAH metabolite; Dab; Flounder; Haddock; Marine monitoring; Atlantic; North Sea. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00317/42861/42288.pdf |
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Registros recuperados: 35 | |
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