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Pedro Reis Costa - One of the best experts on this subject based on the ideXlab platform.
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are pelagic seabirds exposed to Amnesic Shellfish Poisoning toxins
Harmful Algae, 2019Co-Authors: Lucia Solino, Joan Ferrerobiol, Leia Navarroherrero, Jacob Gonzalezsolis, Pedro Reis CostaAbstract:Abstract Marine birds have been hypothesized to be underreported victims of harmful algal blooms (HABs). Toxic blooms of Pseudo-nitzschia spp., the primary Amnesic toxin producer microalgae, domoic acid (DA) are known to cause massive mortalities of coastal seabirds and marine mammals around the world. However, these fatalities are only detected when birds die nearby the coastline and little is known about possible outbreaks of pelagic seabirds in oceanic areas. Here we aim to understand whether pelagic seabirds are exposed to Amnesic Shellfish Poisoning (ASP) toxins. For this purpose, we tracked pelagic seabirds feeding on small epipelagic fish and squid, reported to be vectors of DA, which are obtained in high productivity zones where intense Pseudo-nitzschia blooms regularly occur. In particular, we tracked Cory’s (Calonectris borealis) and Scopoli’s (C. diomedea) shearwaters breeding in Gran Canaria (Canary Is.) and in Menorca (Balearic Is.) and feeding on the Canary Current region and the Catalonian coast, respectively. We sampled birds for blood at the recovery of the GPS (Global Positioning System) and analyzed it for DA determination by Liquid Chromatography coupled with Tandem Mass Spectrometry (LC–MS/MS). Among the 61 samples analyzed from Gran Canaria, and 87 from Menorca, 31 (50.8%) and 28 (32.2%) from each location presented detectable levels of DA ranging 1.0–10.6 ng mL−1. This work reveals that DA can be detected at variable levels in the blood of ASP-asymptomatic shearwaters and suggests a chronic exposure of shearwaters to DA, highlighting the need for further studies on DA effects. These results are of high relevance due to the vulnerability of these marine birds, which populations are in continuous decline. Since global warming is expected to alter and increase the occurrence of HABs, marine toxins might become an additional stressor for seabirds and exacerbate the already precarious conservation status of many species.
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presence and persistence of the Amnesic Shellfish Poisoning toxin domoic acid in octopus and cuttlefish brains
Marine Environmental Research, 2018Co-Authors: Pedro Reis Costa, Rui Rosa, Vanessa M LopesAbstract:Abstract Domoic acid (DA) is a neurotoxin that causes degenerative damage to brain cells and induces permanent short-term memory loss in mammals. In cephalopod mollusks, although DA is known to accumulate primarily in the digestive gland, there is no knowledge whether DA reaches their central nervous system. Here we report, for the first time, the presence of DA in brain tissue of the common octopus (Octopus vulgaris) and the European cuttlefish (Sepia officinalis), and its absence in the brains of several squid species (Loligo vulgaris, L. forbesi and Todarodes sagittatus). We argue that such species-specific differences are related to their different life strategies (benthic/nektobenthic vs pelagic) and feeding ecologies, as squids mainly feed on pelagic fish, which are less prone to accumulate phycotoxins. Additionally, the temporal persistence of DA in octopus’ brain reinforces the notion that these invertebrates can selectively retain this phycotoxin. This study shows that two highly-developed invertebrate species, with a complex central nervous system, where glutamatergic transmission is involved in vertebrate-like long-term potentiation (LTP), have the ability of retaining and possibly tolerating chronic exposure to DA, a potent neurotoxin usually acting at AMPA/kainate-like receptors. Here, we filled a gap of information on whether cephalopods accumulated this neurotoxin in brain tissue, however, further studies are needed to determine if these organisms are neurally or behaviourally impaired by DA.
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accumulation transformation and tissue distribution of domoic acid the Amnesic Shellfish Poisoning toxin in the common cuttlefish sepia officinalis
Aquatic Toxicology, 2005Co-Authors: Pedro Reis Costa, Rui Rosa, Alexandra Duartesilva, Vanda Brotas, Maria Antonia De M SampayoAbstract:Domoic acid (DA) is a phycotoxin produced by some diatoms, mainly from the Pseudo-nitzschia genus, and has been detected throughout the marine food web. Although DA has been frequently found in cephalopod prey such as crustaceans and fish, little is known about DA accumulation in these molluscs. This study presents the first data showing relevant concentrations of DA detected in the common cuttlefish, Sepia officinalis, which is one of the most studied cephalopod species in the world. Domoic acid was consistently found throughout 2003 and 2004 in the digestive gland of cuttlefish reaching concentrations of 241.7 microg DA g(-1). The highest DA values were detected during spring and summer months, periods when Pseudo-nitzschia occur in the plankton. In fact, Pseudo-nitzschia blooms preceded the highest DA concentrations in cuttlefish. Evaluation of DA tissue distribution showed elevated DA concentrations in the digestive gland and branchial hearts. Further, DA isomers comprised a relevant percentage of the toxin profile, indicating degradation and biotransformation of the toxin in the branchial hearts. The common cuttlefish, like other cephalopod species, plays a central position in the food web and might be a new DA vector to top predators like marine mammals. Human intoxications are not expected since DA was only seldom detected in the mantle and even then in very low levels (max 0.7 microg DA g(-1)). However, in some countries whole juvenile animals are consumed (i.e. without evisceration) and in this case they might represent a risk to human health. This study contributes to understanding the occurrence of phycotoxins in cephalopods and reveals a new member of the marine food web able to accumulate DA.
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Detection of domoic acid, the Amnesic Shellfish toxin, in the digestive gland of
'EDP Sciences', 2005Co-Authors: Pedro Reis Costa, Rui Rosa, João Pereira, Maria Antonia De M SampayoAbstract:Domoic acid (DA), the toxin responsible for the illness known as Amnesic Shellfish Poisoning (ASP), is an algal toxin produced naturally by some species of the diatom genus Pseudo-nitzschia. The toxin has been detected in a diverse array of marine organisms from copepods to whales. Cephalopods, which are important members of the food chain and active predators of known toxin vectors such as bivalves, crabs and some fishes, have just recently been implicated in DA transfer or accumulation. Here we present data showing detectable values of DA determined by HPLC-UV (high-performance liquid chromatography and ultraviolet detection) and confirmed by HPLC-MS (mass spectrometric detection) in two octopus species collected along the Portuguese continental coast: Eledone cirrhosa and E. moschata. Domoic acid was frequently detected in the digestive gland of E. moschata and occasionally reached concentrations exceeding 100 µg g−1. In contrast, E. cirrhosa contained lower concentrations of DA on the few occasions that it was detected. This suggests that E. moschata is a potential vector for DA transfer to higher trophic levels in the coastal marine food web, not excluding humans. These data, combined with known aspects of the life history of the species, are a necessary step towards achieving an understanding of the accumulation of phycotoxins in cephalopods
Zhijun Tan - One of the best experts on this subject based on the ideXlab platform.
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pseudo nitzschia simulans sp nov bacillariophyceae the first domoic acid producer from chinese waters
Harmful Algae, 2017Co-Authors: Chun Xiu Huang, Nina Lundholm, Sing Tung Teng, Zhijun TanAbstract:The genus Pseudo-nitzschia has attracted attention because of production of the toxin, domoic acid (DA), causing Amnesic Shellfish Poisoning (ASP). Pseudo-nitzschia blooms occur frequently in Chinese coastal waters, and DA has been detected in several marine organisms, but so far no Pseudo-nitzschia strains from Chinese waters have been shown to produce DA. In this study, monoclonal Pseudo-nitzschia strains were established from Chinese coastal waters and examined using light microscopy, electron microscopy and molecular markers. Five strains, sharing distinct morphological and molecular features differentiating them from other Pseudo-nitzschia species, represent a new species, Pseudo-nitzschia simulans sp. nov. Morphologically, the taxon belongs to the P. pseudodelicatissima group, cells possessing a central nodule and each stria comprising one row of poroids. The new species is characterized by the poroid structure, which typically comprises two sectors, each sector located near opposite margins of the poroid. The production of DA was examined by liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses of cells in stationary growth phase. Domoic acid was detected in one of the five strains, with concentrations around 1.05-1.54 fg cell-1. This is the first toxigenic diatom species reported from Chinese waters.
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Pseudo-nitzschia simulans sp. nov. (Bacillariophyceae), the first domoic acid producer from Chinese waters
'Elsevier BV', 2017Co-Authors: Li Yang, Nina Lundholm, Chun Xiu Huang, Sing Tung Teng, Shuang Xu Guo, Wu Haiyan, Zhijun TanAbstract:The genus Pseudo-nitzschia has attracted attention because of production of the toxin, domoic acid (DA), causing Amnesic Shellfish Poisoning (ASP). Pseudo-nitzschia blooms occur frequently in Chinese coastal waters, and DA has been detected in several marine organisms, but so far no Pseudo-nitzschia strains from Chinese waters have been shown to produce DA. In this study, monoclonal Pseudo-nitzschia strains were established from Chinese coastal waters and examined using light microscopy, electron microscopy and molecular markers. Five strains, sharing distinct morphological and molecular features differentiating them from other Pseudo-nitzschia species, represent a new species, Pseudo-nitzschia simulans sp. nov. Morphologically, the taxon belongs to the P. pseudodelicatissima group, cells possessing a central nodule and each stria comprising one row of poroids. The new species is characterized by the poroid structure, which typically comprises two sectors, each sector located near opposite margins of the poroid. The production of DA was examined by liquid chromatography tandem mass spectrometry (LC–MS/MS) analyses of cells in stationary growth phase. Domoic acid was detected in one of the five strains, with concentrations around 1.05–1.54 fg cell�1. This is the first toxigenic diatom species reported from Chinese waters
Gregory J Doucette - One of the best experts on this subject based on the ideXlab platform.
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determination of domoic acid in seawater and phytoplankton by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2007Co-Authors: Zhihong Wang, Kristen L King, John S Ramsdell, Gregory J DoucetteAbstract:Domoic acid (DA) is an algal neurotoxin produced by diatoms primarily of the genus Pseudo-nitzschia and is responsible for the human intoxication syndrome known as Amnesic Shellfish Poisoning. A method has been developed to determine DA in seawater and phytoplankton matrices by liquid chromatography-tandem mass spectrometry for both quantitation and confirmation purposes. Sample extraction and clean-up was achieved on a C18 solid-phase extraction (SPE) cartridge. An acidic condition is critical for retaining hydrophilic DA on the cartridge. Direct injection of SPE eluate for analysis is recommended in order to avoid loss of DA by drying with heat prior to resuspension and injection. DA was quantified using the fragments produced from the protonated DA ion through multiple reaction monitoring (MRM). Recoveries exceeded 90% for all seawater samples spiked with DA and approximated 98% of toxin standard added to cultured phytoplankton material. Acceptable reproducibility (ca. 5% or less) was obtained for all intra-day and inter-day samples. The detection limit was 30 pg/ml level with a 20 microl injection volume, which demonstrated the value of this method for not only confirming DA production by minimally toxic phytoplankton species, but also for investigating the potentially important role of dissolved DA in marine food webs.
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isodomoic acid c an unusual Amnesic Shellfish Poisoning toxin from pseudo nitzschia australis
Chemical Research in Toxicology, 2005Co-Authors: Patrick T Holland, Andrew I Selwood, Douglas O Mountfort, Alistair L Wilkins, Paul Mcnabb, Lesley L Rhodes, Gregory J Doucette, Christina M Mikulski, Kristen L KingAbstract:An unusual isomer of domoic acid (1), isodomoic acid C (2), has been found in New Zealand Shellfish contaminated by Amnesic Shellfish Poisoning (ASP) toxins and was shown to be produced by a local strain of the pennate diatom Pseudo-nitzschia australis. A bulk culture of this strain was used to isolate 2. The structure was determined from spectroscopic data and was shown to correspond to that of 2 from a Japanese red seaweed, the only other reported occurrence of this compound. The affinity of 2 for GluR6 glutamate receptors was 240-fold lower than for 1, indicating low neurotoxic potential.
Juan Blanco - One of the best experts on this subject based on the ideXlab platform.
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RNA-Seq Transcriptome Profiling of the Queen Scallop (Aequipecten opercularis) Digestive Gland after Exposure to Domoic Acid-Producing Pseudo-nitzschia
MDPI AG, 2019Co-Authors: Pablo Ventoso, Juan Blanco, Antonio J. Pazos, Luz M. Pérez-parallé, Juan C. Triviño, José L. SánchezAbstract:Some species of the genus Pseudo-nitzschia produce the toxin domoic acid, which causes Amnesic Shellfish Poisoning (ASP). Given that bivalve mollusks are filter feeders, they can accumulate these toxins in their tissues. To elucidate the transcriptional response of the queen scallop Aequipecten opercularis after exposure to domoic acid-producing Pseudo-nitzschia, the digestive gland transcriptome was de novo assembled using an Illumina HiSeq 2000 platform. Then, a differential gene expression analysis was performed. After the assembly, 142,137 unigenes were obtained, and a total of 10,144 genes were differentially expressed in the groups exposed to the toxin. Functional enrichment analysis found that 374 Pfam (protein families database) domains were significantly enriched. The C1q domain, the C-type lectin, the major facilitator superfamily, the immunoglobulin domain, and the cytochrome P450 were among the most enriched Pfam domains. Protein network analysis showed a small number of highly connected nodes involved in specific functions: proteasome components, mitochondrial ribosomal proteins, protein translocases of mitochondrial membranes, cytochromes P450, and glutathione S-transferases. The results suggest that exposure to domoic acid-producing organisms causes oxidative stress and mitochondrial dysfunction. The transcriptional response counteracts these effects with the up-regulation of genes coding for some mitochondrial proteins, proteasome components, and antioxidant enzymes (glutathione S-transferases, thioredoxins, glutaredoxins, and copper/zinc superoxide dismutases)
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high throughput analysis of Amnesic Shellfish Poisoning toxins in bivalve molluscs by dispersive solid phase extraction and high performance liquid chromatography using a monolithic column
Food Chemistry, 2011Co-Authors: Jorge Regueiro, Aida Mauriz, Gonzalo Alvarez, Juan BlancoAbstract:Abstract Domoic acid and its isomers are algal neurotoxins responsible for the human intoxication syndrome known as Amnesic Shellfish Poisoning. A rapid and simple HPLC–UV/DAD method based on the use of a monolithic silica column is proposed for the determination of ASP toxins in Shellfish samples. To the best of our knowledge, a monolithic column is applied for the first time to the analysis of marine toxins. An experimental design strategy was employed to evaluate the influence of the main variables potentially affecting the chromatographic separation. Optimal conditions were selected by means of a multi-response optimisation approach, aiming to minimise retention times while maintaining enough resolution between isomers. Dispersive solid-phase extraction (dSPE) is proposed as a complementary cleanup procedure in order to reduce chromatographic interferences and to increase column lifetime. Amongst several sorbents, graphitized non-porous carbon provided the best results. Method performance was evaluated in terms of accuracy, precision, linearity and limits of detection (LODs). Quantitative recoveries (⩾89%) and satisfactory method precision (RSD ⩽ 6%) were obtained. LODs at the nanogram per gram level were achieved. To demonstrate the applicability of the proposed method, several Shellfish samples from North-western Spain were analysed, including scallops, mussels, Manila clams, common edible cockles and razor clams.
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Amnesic Shellfish Poisoning asp toxins in plankton and molluscs from luanda bay angola
Toxicon, 2010Co-Authors: Juan Blanco, Filomena Livramento, Isabel RangelAbstract:The presence of ASP toxins in Luanda Bay, an area 2700 km apart from the closest record of this type of toxicity and with a different hydrographic regime, was studied. Two outbreaks were confirmed by LC/MS/MS with presence of domoic acid and some isomers both, in plankton and in three of the most important bivalve species from the area. Domoic acid levels in the studied bivalves were below the regulatory limits for most countries and the first estimations indicate that they depurated the toxin quickly. It is, therefore, unlikely that any intoxication would have taken place by consumption of these bivalve species. Notwithstanding, the relatively high annual frequency of the blooms together with possibility that other bivalve species could retain this compound more strongly, suggest that this kind of intoxication might pose a significant risk in Angola.
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depuration and anatomical distribution of the Amnesic Shellfish Poisoning asp toxin domoic acid in the king scallop pecten maximus
Aquatic Toxicology, 2002Co-Authors: Juan Blanco, C P Acosta, Bermudez M De La Puente, Covadonga SalgadoAbstract:The depuration kinetics of the domoic acid of four body fractions (digestive gland, adductor muscle, gonad+kidney and gills+mantle) of the scallop Pecten maximus was studied over 295 days. The scallops, which had acquired the toxins during a Pseudo-nitzschia australis episode that took place the week before the beginning of the experiment, were maintained in tanks with running seawater. All the body fractions, except the adductor muscle, decreased their domoic acid burden throughout the experiment. The amount of toxin in the muscle dropped sharply at the start of the experiment but increased again at the end, to levels that were higher than the initial ones. Several dynamic models of depuration kinetics, which included the depuration of each fraction (excluding the adductor muscle) and the transfers between them, were constructed, implemented and fitted to the data to obtain their parameters. The estimated depuration rates were very low, both considering and not considering the transfer of toxin between organs or the effect of weight loss. There were strong differences in the domoic acid burden of the body fractions studied but not between their depuration rates. No net transfer from the digestive gland, the tissue with highest domoic acid concentration, to the other fractions was found, as the inclusion of these processes in the models produced only a marginally better fit to the data. The depuration of domoic acid was slightly, but significantly, affected by biomass. Weight loss induced domoic acid loss, suggesting that part of the depuration may be produced by the direct loss of bivalve cells. The concentration or dilution effect, due to decreases or increases in biomass, documented for other species and toxins, has little importance in Pecten maximus.
Kristen L King - One of the best experts on this subject based on the ideXlab platform.
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determination of domoic acid in seawater and phytoplankton by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2007Co-Authors: Zhihong Wang, Kristen L King, John S Ramsdell, Gregory J DoucetteAbstract:Domoic acid (DA) is an algal neurotoxin produced by diatoms primarily of the genus Pseudo-nitzschia and is responsible for the human intoxication syndrome known as Amnesic Shellfish Poisoning. A method has been developed to determine DA in seawater and phytoplankton matrices by liquid chromatography-tandem mass spectrometry for both quantitation and confirmation purposes. Sample extraction and clean-up was achieved on a C18 solid-phase extraction (SPE) cartridge. An acidic condition is critical for retaining hydrophilic DA on the cartridge. Direct injection of SPE eluate for analysis is recommended in order to avoid loss of DA by drying with heat prior to resuspension and injection. DA was quantified using the fragments produced from the protonated DA ion through multiple reaction monitoring (MRM). Recoveries exceeded 90% for all seawater samples spiked with DA and approximated 98% of toxin standard added to cultured phytoplankton material. Acceptable reproducibility (ca. 5% or less) was obtained for all intra-day and inter-day samples. The detection limit was 30 pg/ml level with a 20 microl injection volume, which demonstrated the value of this method for not only confirming DA production by minimally toxic phytoplankton species, but also for investigating the potentially important role of dissolved DA in marine food webs.
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isodomoic acid c an unusual Amnesic Shellfish Poisoning toxin from pseudo nitzschia australis
Chemical Research in Toxicology, 2005Co-Authors: Patrick T Holland, Andrew I Selwood, Douglas O Mountfort, Alistair L Wilkins, Paul Mcnabb, Lesley L Rhodes, Gregory J Doucette, Christina M Mikulski, Kristen L KingAbstract:An unusual isomer of domoic acid (1), isodomoic acid C (2), has been found in New Zealand Shellfish contaminated by Amnesic Shellfish Poisoning (ASP) toxins and was shown to be produced by a local strain of the pennate diatom Pseudo-nitzschia australis. A bulk culture of this strain was used to isolate 2. The structure was determined from spectroscopic data and was shown to correspond to that of 2 from a Japanese red seaweed, the only other reported occurrence of this compound. The affinity of 2 for GluR6 glutamate receptors was 240-fold lower than for 1, indicating low neurotoxic potential.