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| Registros recuperados: 91 | |
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| Hess, Philipp; Mondeguer, Florence; Glauner, Thomas; Wust, Bernard; Sibat, Manoella; Zendong, Suzie Zita; Herrenknecht, Christine; Sechet, Veronique. |
| Out of the circa 5000 microalgae known, around 100 marine species of unicellular algae have been shown to produce several hundred biotoxins worldwide. Such biotoxins may be harmful to man through consumption of fish and shellfish exposed to such algae or through direct contact. Many official methods aimed at the detection of such toxins had traditionally been based on biological assays, due to the lack of reference compounds. Recently, legislation for shellfish safety in Europe introduced targeted MS screening for lipophilic toxins. Due to globalization of trade and climate change, there is a need to develop methods for untargeted screening to fully protect consumer safety, e.g. LC-HRMS. For this purpose we studied the metabolomes of marine microalgae... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00179/29037/27473.pdf |
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| Zendong, Suzie Zita; Herrenknecht, Christine; Mondeguer, Florence; Hess, Philipp. |
| By 2014, the new targeted LC-MS/MS reference method for the detection of lipophilic toxins will replace the mouse bioassay (MBA). This bioassay, which has the advantage of being a rapid and global toxicity test, can not be used for toxin identification purposes. Furthermore, it has appeared that, in some cases, the mouse bioassay could reveal uncharacterized toxicities that could not be elucidated by targeted mass spectrometry methods. Therefore, moving from the global toxicity assessment test to a targeted technique leads to a lack of information on emerging toxins. Objectives: - Beside targeted methods, develop metabolomic approaches to screen for known and unknown emerging toxins - Develop passive sampling devices suitable for toxins of varying... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00179/29040/27478.pdf |
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| Lassus, Patrick; Chomerat, Nicolas; Hess, Philipp; Nezan, Elisabeth. |
| This book updates available international databases on toxic and harmful species of phytoplankton and micro-phytobenthos. It lists regional occurrences at world-wide scale: localities, cell densities, toxicity levels in contaminated animals, human and animal poisoning, isolation of identified active molecules and toxins, documentary sources. Finally, this book addresses the geographic distributions of phycotoxin-producers from recent data. The objective is to analyze the evolution of toxic and harmful episodes over the past 30 years to identify trends, and to introduce a discussion on the reality of a time-dependent increase in the number of known species and toxins. |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00379/49054/49508.pdf |
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| Mondeguer, Florence; Antignac, Jean-philippe; Guitton, Yann; Monteau, Fabrice; Le Borgne, Sabrina; Hess, Philipp. |
| The bioactivity of phytoplankton toxins that accumulate in shellfish is almost always tested on animal model (mice assay). In spite of these advantages, the ability of this test to explain the nature of the bioactivity remains limited. Besides, the current sanitary control based on targeted methods of identification and quantification (LC-MS/MS) of known toxins, do not permit to detect unknown toxins. In order to cope with this need of identification of unknown toxic substances, a next approach based on global and differential metabolomic profiling was proposed. The first results obtained from extracts that have shown a positive toxicity in mice without the substances potentially responsible for these toxic effects have been measured by targeted methods,... |
| Tipo: Text |
Palavras-chave: Métabolomique; LC-HRMS; Biotoxines marines; Biomarqueur. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18784/16352.pdf |
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| Fleming, L.e.; Mcdonough, N.; Austen, M.; Mee, L.; Moore, Michael; Hess, Philipp; Depledge, M.h.; White, M.; Philippart, Katja; Bradbrook, P.; Smalley, A.. |
| The European Marine Board recently published a position paper on linking oceans and human health as a strategic research priority for Europe. With this position paper as a reference, the March 2014 Cornwall Oceans and Human Health Workshop brought together key scientists, policy makers, funders, business, and non governmental organisations from Europe and the US to review the recent interdisciplinary and cutting edge research in oceans and human health specifically the growing evidence of the impacts of oceans and seas on human health and wellbeing (and the effects of humans on the oceans). These impacts are a complex mixture of negative influences (e.g. from climate change and extreme weather to harmful algal blooms and chemical pollution) and beneficial... |
| Tipo: Text |
Palavras-chave: Harmful algal blooms; Microbial pollution; Anthropogenic chemicals; Marine biotechnology; Climate change; Ocean acidification; Fisheries; Aquaculture; Seafood; Blue carbon; Marine energy; Blue gym; Ocean literacy; Risks; Benefits; EU Policy. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00192/30328/29066.pdf |
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| Tibiriçá, Carlos Eduardo J. A.; Leite, Isabel P.; Batista, Talita V. V.; Fernandes, Luciano F.; Chomérat, Nicolas; Herve, Fabienne; Hess, Philipp; Mafra, Luiz. |
| Ostreopsis cf. ovata is a toxic marine benthic dinoflagellate responsible for harmful blooms affecting ecosystem and human health, mostly in the Mediterranean Sea. In this study we report the occurrence of a summer O. cf. ovata bloom in Currais, a coastal archipelago located on the subtropical Brazilian coast (~25° S). This bloom was very similar to Mediterranean episodes in many aspects: (a) field-sampled and cultivated O. cf. ovata cells aligned phylogenetically (ITS and LSU regions) along with Mediterranean strains; (b) the bloom occurred at increasing temperature and irradiance, and decreasing wind speed; (c) cell densities reached up to 8.0 × 104 cell cm−2 on fiberglass screen and 5.6 × 105 cell g−1 fresh weight on seaweeds; (d) and toxin profiles... |
| Tipo: Text |
Palavras-chave: Harmful algal bloom; Benthic microalgae; Toxic dinoflagellates; Ovatoxin; Toxin transfer; Seafood safety; Marine pollution; Plastic litter; Biofilm formation. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00509/62037/66177.pdf |
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| Nascimento, Silvia M; Neves, Raquel Af; De'Carli, Gabriela Al; Borsato, Geovanna T; Da Silva, Rodrigo Af; Melo, Guilherme A; De Morais, Agatha M; Cockell, Thais C; Fraga, Santiago; Menezes-salgueiro, Adriana D; Mafra, Luis L Jr; Hess, Philipp; Salgueiro, Fabiano. |
| Recurrent blooms of Ostreopsis cf. ovata have been reported in Brazil and the Mediterranean Sea with associated ecological, and in the latter case, health impacts. Molecular data based on the D1–D3 and D8–D10 regions of the LSU rDNA and ITS loci, and the morphology of O. cf. ovata isolates and field populations from locations along the Brazilian tropical and subtropical coastal regions and three oceanic islands are presented. Additional ITS sequences from three single cells from the tropical coast are provided. Toxin profiles and quantities of PLTX and their analogues; OVTXs; contained in cells from two clonal cultures and two field blooms from Rio de Janeiro were investigated. Morphology was examined using both light and epifluorescence microscopy.... |
| Tipo: Text |
Palavras-chave: Benthic dinoflagellates; Harmful algal blooms; Ovatoxins; Taxonomy; Morphometry. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00604/71594/70026.pdf |
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| Hess, Philipp; Abadie, Eric; Herve, Fabienne; Berteaux, Tom; Sechet, Veronique; Araoz, Romulo; Molgo, Jordi; Zakarian, Armen; Sibat, Manoella; Rundberget, Thomas; Miles, Christopher O.; Amzil, Zouher. |
| Following a review of official control data on shellfish in France, Ingril Lagoon had been identified as a site where positive mouse bioassays for lipophilic toxins had been repeatedly observed. These unexplained mouse bioassays, also called atypical toxicity, coincided with an absence of regulated toxins and rapid death times in mice observed in the assay. The present study describes pinnatoxin G as the main compound responsible for the toxicity observed using the mouse bioassay for lipophilic toxins. Using a well-characterised standard for pinnatoxin G, LC-MS/MS analysis of mussel samples collected from 2009 to 2012 revealed regular occurrences of pinnatoxin G at levels sufficient to account for the toxicity in the mouse bioassays. Baseline levels of... |
| Tipo: Text |
Palavras-chave: Cyclic imines; Shellfish toxin; Accumulation; Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS); Unexplained mouse toxicity. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00158/26960/25255.pdf |
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| Hess, Philipp; Herve, Fabienne; Abadie, Eric; Sechet, Veronique; Molgo, Jordi; Amzil, Zouher; Fessard, Valerie. |
| Suite à la découverte de la Pinnatoxine G comme agent responsable des toxicités atypiques à Ingril fin 2010, une étude a été commanditée afin d’approfondir les connaissances sur l’organisme producteur de cette toxine, Vulcanodinium rugosum, les toxines associées et leur toxicité. L’organisme, étant considéré « cryptique » dû à sa faible présence dans le milieu, a été suivi de manière plus proche à Ingril. Il est apparu dans la colonne d’eau en juillet et août 2012, et quelques échantillons ont pu être prélevés pour la mise en culture de souches supplémentaires. Une corrélation directe entre la croissance de l’organisme et la température est soupçonnée mais n’a pas encore pu être corroborée sur la période d’étude, faute d’un nombre suffisant... |
| Tipo: Text |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00094/20518/18190.pdf |
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| Mondeguer, Florence; Abadie, Eric; Herve, Fabienne; Bardouil, Michele; Sechet, Veronique; Raimbault, Virginie; Berteaux, Tom; Zendong, Suzie Zita; Palvadeau, Hubert; Amzil, Zouher; Hess, Philipp; Fessard, Valérie; Huguet, Antoine; Sosa, Silvio; Tubaro, Aurelia; Aráoz, Rómulo; Molgó, Jordi. |
| Pour tenter d’apporter des réponses aux questions soulevées par une précédente étude commanditée pour approfondir les connaissances sur Vulcanodinium rugosum, l’organisme producteur de la Pinnatoxine G (PnTX G) (Hess et al., 2012), les objectifs de cette nouvelle étude sont les suivants : - Elargissement de la zone initiale de prélèvement d’Ingril à toute la lagune méditerranéenne et mise à profit de l’augmentation du nombre d’échantillons pour vérifier l’impact de l’effet matrice dans l’analyse LC-SM/MS. - Mise en culture en masse de Vulcanodinium rugosum et - Conduite d’une expérience de contamination in vivo sur des moules pour vérifier l’accumulation de la PnTX-G et comprendre les mécanismes de la métabolisation des PnTXs et de ses composés associés..... |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00285/39635/38126.pdf |
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| Mondeguer, Florence; Sibat, Manoella; Reubrecht, Sébastien; Amzil, Zouher; Bormans, Myriam; Hess, Philipp; Briand, Enora. |
| Cyanobacterial proliferation is one of the most harmful hazards, in both freshwater and marine ecosystems. Cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. By integrating LC-MS/MS molecular networking and an innovative experimental design, we... |
| Tipo: Text |
Palavras-chave: Cyanobacteria; Cyanotoxins; Plankton interactions; Co_culture; LC_HRMS; Molecular Network; Metabolomics. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00405/51666/52215.pdf |
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| Jauffrais, Thierry; Kilcoyne, Jane; Sechet, Veronique; Herrenknecht, Christine; Truquet, Philippe; Herve, Fabienne; Berard, Jean-baptiste; Nulty, Ciara; Taylor, Sarah; Tillmann, Urban; Miles, Christopher O.; Hess, Philipp. |
| Azaspiracid (AZA) poisoning has been reported following consumption of contaminated shellfish, and is of human health concern. Hence, it is important to have sustainable amounts of the causative toxins available for toxicological studies and for instrument calibration in monitoring programs, without having to rely on natural toxin events. Continuous pilot scale culturing was carried out to evaluate the feasibility of AZA production using Azadinium spinosum cultures. Algae were harvested using tangential flow filtration or continuous centrifugation. AZAs were extracted using solid phase extraction (SPE) procedures, and subsequently purified. When coupling two stirred photobioreactors in series, cell concentrations reached 190,000 and 210,000 cell·mL−1 at... |
| Tipo: Text |
Palavras-chave: Solid phase extraction; Photobioreactor; Chemostat; Dinoflagellate; Micro-algae; LC-MS/MS; Tangential flow filtration; Azaspiracid; HP-20. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00088/19875/17526.pdf |
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| Jauffrais, Thierry; Herrenknecht, Christine; Sechet, Veronique; Sibat, Manoella; Tillmann, Urban; Krock, Bernd; Kilcoyne, Jane; Miles, Christopher O.; Mccarron, Pearse; Amzil, Zouher; Hess, Philipp. |
| Azaspiracids (AZAs) are secondary metabolites of Azadinium spinosum, that have been shown to cause diarrhetic shellfish poisoning when accumulated in bivalve molluscs. We describe here an analytical procedure for the determination of AZAs in cultures of A. spinosum with a focus on the potential formation of AZA methyl-esters as artefacts in the extraction and sample pre-treatment. A. spinosum cells were collected from bioreactor cultures, using centrifugation or filtration. Different extraction procedures were evaluated for formation of methyl-ester artefacts, yield, and matrix effects. Filtration of cultures using glass-fibre filters led to increased formation of methyl-esters. Hence centrifugation is recommended for recovery of cells. The type of... |
| Tipo: Text |
Palavras-chave: Extraction procedure; Extraction artefact; Matrix effects; LC-MS/MS; Azaspiracid methyl ester; Dinoflagellate; Liquid chromatography-mass spectrometry. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18812/16463.pdf |
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| Hess, Philipp; Nicolau, Elodie. |
| Over the past seven years, methods available for the detection of phycotoxins have been extensively reviewed in a number of international expert committees, such as the consultations organised by FAO/IOC/WHO and EFSA, as well as by individual scientists. These reviews have shown that the methods available have severe limitations for the use in official control, either due to their limited scope and detection capability or due to a lack of calibration standards, reference materials and validation efforts. The present review focuses on recent developments in the detection of phycotoxins in several areas of applied research. Not being able to exhaustively describe all recent developments, the review focussed on three areas of interest to the authors: (i)... |
| Tipo: Text |
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| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00019/12975/9949.pdf |
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| Zendong, Suzie Zita; Sibat, Manoella; Herrenknecht, Christine; Hess, Philipp; Mccarron, Pearse. |
| Rationale Accurate quantitative analysis of lipophilic toxins by liquid chromatography-mass spectrometry (LC-MS) requires calibration solution reference materials (RMs) for individual toxin analogs. Untargeted analysis is aimed at identifying a vast number of compounds and thus validation of fully quantitative untargeted methods is not feasible. However, a semi-quantitative approach allowing for profiling is still required and will be strengthened by knowledge of the relative molar response (RMR) of analogs in liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization (ESI). Methods RMR factors were evaluated for toxins from the okadaic acid (OA/DTXs), yessotoxin (YTX), pectenotoxin (PTX), azaspiracid (AZA) and cyclic imine (CI) toxin... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00387/49877/50434.pdf |
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| Hess, Philipp. |
| An overview is given of the biological origin of phycotoxins, as well as their chemical characteristics. Major poisoning types are described and examples of poisoning events are given to illustrate the importance of the phenomenon to both shellfish consumers and the shellfish producing industry. The characteristics of phycotoxins as natural products, the lack of predictability of their occurrence, economic drivers and the freshness of shellfish consumed in many countries result in a number of requirements for methods to be used in the efficient detection of these compounds. Subsequently, the performance of mouse bioassays and mass spectrometry as detection tools are compared for examples from Irish and French monitoring programmes to assess the usefulness... |
| Tipo: Text |
Palavras-chave: Bioanalytical methods; Bioassays; Mass spectrometry; Liquid chromatography; Biological samples. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11767/8989.pdf |
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| Mondeguer, Florence; Antignac, Jean-philippe; Guitton, Yann; Monteau, Fabrice; Le Borgne, Sabrina; Hess, Philipp. |
| La bioactivité des toxines du phytoplancton qui s’accumulent dans les coquillages est presque toujours évaluée sur modèle animal (test souris). Malgré ses avantages, la capacité de ce test à expliquer la nature de cette bio-activité reste limitée. Par ailleurs, le contrôle sanitaire actuellement basé sur une méthode ciblée d’identification et de quantification d’un ensemble de toxines connues ne permet pas de détecter des toxines encore inconnues. Afin de répondre à ce besoin de caractérisation de substances toxiques inconnues, une nouvelle approche de profilage chimique différentiel et non ciblé, de type métabolomique, a été proposée. Les 2 extraits sélectionnés sont ceux ayant montré une toxicité positive chez la souris, sans que les substances... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00179/29042/27480.pdf |
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| Kilcoyne, Jane; Twiner, Michael J.; Mccarron, Pearse; Crain, Sheila; Giddings, Sabrina D.; Foley, Barry; Rise, Frode; Hess, Philipp; Willdns, Alistair L.; Miles, Christopher O.. |
| Azaspiracids (AZAs) are marine biotoxins produced by dinoflagellates that can accumulate in shellfish, which if consumed can lead to poisoning events. AZA7–10, 7–10, were isolated from shellfish and their structures, previously proposed on the basis of only LC–MS/MS data, were confirmed by NMR spectroscopy. Purified AZA4–6, 4–6, and 7–10 were accurately quantitated by qNMR and used to assay cytotoxicity with Jurkat T lymphocyte cells for the first time. LC–MS(MS) molar response studies performed using isocratic and gradient elution in both selected ion monitoring and selected reaction monitoring modes showed that responses for the analogues ranged from 0.3 to 1.2 relative to AZA1, 1. All AZA analogues tested were cytotoxic to Jurkat T lymphocyte cells in a... |
| Tipo: Text |
Palavras-chave: Azaspiracid; Structure confirmation; LC-MS molar response; NMR; Mass spectrometry; Purification; Jurkat T; Toxicity. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00269/38059/36190.pdf |
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| Kilcoyne, Jane; Mccarron, Pearse; Hess, Philipp; Miles, Christopher O.. |
| This dataset is composed by the supporting information of Kilcoyne Jane, Mccarron Pearse, Hess Philipp, Miles Christopher O. (2015). Effects of Heating on Proportions of Azaspiracids 1–10 in Mussels ( Mytilus edulis ) and Identification of Carboxylated Precursors for Azaspiracids 5, 10, 13, and 15. Journal of Agricultural and Food Chemistry, 63(51), 10980-10987. http://dx.doi.org/10.1021/acs.jafc.5b04609 |
| Tipo: Dataset |
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| Ano: 2015 |
URL: http://dx.doi.org/10.17882/41845 |
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| Registros recuperados: 91 | |
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