Consulta: creatorFacets:"Twiner, Michael J."
Registros recuperados: 4
Data/hora: 02/06/2024 13:25:53

Isolation, Structure Elucidation, Relative LC-MS Response, and in Vitro Toxicity of Azaspiracids from the Dinoflagellate Azadinium spinosum
Provedor de dados: 5
Autores: Kilcoyne, Jane; Nulty, Ciara; Jauffrais, Thierry; Mccarron, Pearse; Herve, Fabienne; Foley, Barry; Rise, Frode; Crain, Sheila; Wilkins, Alistair L.; Twiner, Michael J.; Hess, Philipp; Miles, Christopher O.
We identified three new azaspiracids (AZAs) with molecular weights of 715, 815, and 829 (AZA33 (3), AZA34 (4), and AZA35, respectively) in mussels, seawater, and Azadinium spinosum culture. Approximately 700 mu g of 3 and 250 mu g of 4 were isolated from a bulk culture of A. spinosum, and their structures determined by MS and NMR spectroscopy. These compounds differ significantly at the carboxyl end of the molecule from known AZA analogues and therefore provide valuable information on structure-activity relationships. Initial toxicological assessment was performed using an in vitro model system based on Jurkat T lymphocyte cytotoxicity, and the potencies of 3 and 4 were found to be 0.22- and 5.5-fold that of AZA1 (1), respectively. Thus, major changes in...
Tipo: Text
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00245/35606/34414.pdf

Azaspiracid shellfish poisoning: A review on the chemistry, ecology, and toxicology with an emphasis on human health impacts
Provedor de dados: 5
Autores: Twiner, Michael J.; Rehmann, Nils; Hess, Philipp; Doucette, Gregory J.
Azaspiracids (AZA) are polyether marine toxins that accumulate in various shellfish species and have been associated with severe gastrointestinal human intoxications since 1995. This toxin class has since been reported from several countries, including Morocco and much of western Europe. A regulatory limit of 160 mu g AZA/kg whole shellfish flesh was established by the EU in order to protect human health; however, in some cases, AZA concentrations far exceed the action level. Herein we discuss recent advances on the chemistry of various AZA analogs, review the ecology of AZAs, including the putative progenitor algal species, collectively interpret the in vitro and in vivo data on the toxicology of AZAs relating to human health issues, and outline the...
Tipo: Text
Palavras-chave: Azaspiracid (AZA); AZP; Shellfish poisoning.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/00077/18805/16375.pdf

Structure Elucidation, Relative LC–MS Response and In Vitro Toxicity of Azaspiracids 7–10 Isolated from Mussels (Mytilus edulis)
Provedor de dados: 5
Autores: 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

Identification of 21,22-Dehydroazaspiracids in Mussels (     Mytilus edulis     ) and in Vitro Toxicity of Azaspiracid-26
Provedor de dados: 5
Autores: Kilcoyne, Jane; Mccarron, Pearse; Twiner, Michael J.; Rise, Frode; Hess, Philipp; Wilkins, Alistair L.; Miles, Christopher O.
Azaspiracids (AZAs) are marine biotoxins produced by the genera Azadinium and Amphidoma, pelagic marine dinoflagellates that may accumulate in shellfish resulting in human illness following consumption. The complexity of these toxins has been well documented, with more than 40 structural variants reported that are produced by dinoflagellates, result from metabolism in shellfish, or are extraction artifacts. Approximately 34 μg of a new AZA with MW 823 Da (AZA26 (3)) was isolated from blue mussels (Mytilus edulis), and its structure determined by MS and NMR spectroscopy. AZA26, possibly a bioconversion product of AZA5, lacked the C-20–C-21 diol present in all AZAs reported thus far and had a 21,22-olefin and a keto group at C-23. Toxicological assessment of...
Tipo: Text
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00428/54001/55286.pdf