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1.
Cienc. tecnol. salud ; 7(1): 137-142, 2020. ^c27 cmilus
Artigo em Espanhol | LILACS | ID: biblio-1121042

RESUMO

Los florecimientos algales nocivos (FAN) son eventos naturales que ocurren cuando una o más especies de microalgas proliferan en concentraciones que pueden causar daño a los organismos acuáticos y a seres humanos que los consuman. En las últimas décadas, se ha registrado a nivel mundial un aumento de eventos de mortalidad alarmante de organismos acuáticos e intoxicaciones en seres humanos causadas por toxinas producidas por microalgas. En Guatemala existe escasa información sobre eventos FAN, no obstante, en diciembre de 2018 ocurrió un FAN en la costa Pacífico de Guatemala. La Comisión Nacional para la Vigilancia y el Control de la Marea Roja Tóxica recolectó muestras biológicas e identificó la presencia de 3,000 cel/L del dinoflagelado Pyrodinium bahamense. El bioensayo en ratón de las muestras, indica concentraciones de saxitoxina de 8,236 UR/100 g y 6,559 UR/100 g, para los días 20 y 27 de diciembre, respectivamente. Estas concentraciones no han sido reportadas previamente en Guatemala, y pueden ser potencialmente tóxicas para la salud pública. Se recomienda mantener un monitoreo de FAN para prevenir impactos negativos en la salud pública y ambiental.


Harmful algal blooms (HABs) are natural events that occur when one or more species of microalgae proliferate at concentrations that can cause damage to aquatic organisms and to those who consume them. In Guatemala very little information exists on HAB events, although in December 2018 has occurred a HABs at the Pacific Coast of Guatemala. A biological sample were collected by the National Commission for Surveillance and Control of Toxic Red Tide. The samples showed 3,000 cel/L of the dinoflagellate Pyrodinium bahamense. During the bioassay for saxitoxin, the concentrations reached 8,236 MU/100 g and 6,559 MU/100 g, for December 20th and 27th, respectively. These concentrations has not been reported previously for Guatemala, and could be a risk in the public health. This result emphasizes the importance of maintaining the HABS monitoring program to prevent negative impact on public environmental health.


Assuntos
Humanos , Dinoflagelados , Proliferação Nociva de Algas , Microalgas/crescimento & desenvolvimento , Fitoplâncton , Saxitoxina/envenenamento , Saúde Ambiental , Vigilância , Eutrofização
2.
Toxins (Basel) ; 11(11)2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683507

RESUMO

Paralytic shellfish poisoning (PSP) is precipitated by a family of toxins produced by harmful algae, which are consumed by filter-feeding and commercially popular shellfish. The toxins, including saxitoxin, neosaxitoxin, and gonyautoxins, accumulate in shellfish and cause intoxication when consumed by humans and animals. Symptoms can range from minor neurological dysfunction to respiratory distress and death. There are over 40 different chemical congeners of saxitoxin and its analogs, many of which are toxic and many of which have low toxicity or are non-toxic. This makes accurate toxicity assessment difficult and complicates decisions regarding whether or not shellfish are safe to consume. In this study, we describe a new antibody-based bioassay that is able to detect toxic congeners (saxitoxin, neosaxitoxin, and gonyautoxins) with little cross-reactivity with the low or non-toxic congeners (decarbamoylated or di-sulfated forms). The anti-saxitoxin antibody used in this assay detects saxitoxin and neosaxitoxin, the two most toxic congers equally well, but not the relatively highly toxic gonyautoxins. By incorporating an incubation step with L-cysteine, it is possible to convert a majority of the gonyautoxins present to saxitoxin and neosaxitoxin, which are readily detected. The assay is, therefore, capable of detecting the most toxic PSP congeners found in commercially relevant shellfish. The assay was validated against samples whose toxicity was determined using standard HPLC methods and yielded a strong linear agreement between the methods, with R2 values of 0.94-0.96. As ELISAs are rapid, inexpensive, and easy-to-use, this new commercially available PSP ELISA represents an advance in technology allowing better safety management of the seafood supply and the ability to screen large numbers of samples that can occur when monitoring is increased substantially in response to toxic bloom events.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Toxinas Marinhas/análise , Saxitoxina/análise , Saxitoxina/toxicidade , Intoxicação por Frutos do Mar , Confiabilidade dos Dados , Saxitoxina/envenenamento
3.
Am J Trop Med Hyg ; 97(6): 1731-1736, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29016314

RESUMO

During the months of January-February and May-June 2013 coinciding with the red tide occurrence in Kota Kinabalu, Sabah, Malaysia, six episodes involving 58 cases of paralytic shellfish poisoning (PSP) or saxitoxin (STX) poisoning and resulting in four deaths were reported. Many of them were intoxicated from consuming shellfish purchased from the markets, whereas others were intoxicated from eating shellfish collected from the beach. Levels of STX in shellfish collected from the affected areas were high (mean 2,920 ± 780 and 360 ± 140 µg STX equivalents/100 g shellfish meat respectively for the two periods). The count of toxic dinoflagellates (Pyrodinium bahamense var compressum) of the sea water sampled around the coast was also high (mean 34,200 ± 10,300 cells/L). Species of shellfish containing high levels of STX were Atrina fragilis, Perna viridis, and Crassostrea belcheri. The age of victims varied from 9 to 67 years. Symptoms presented were typical of PSP, such as dizziness, numbness, vomiting, and difficulty in breathing. Recommended steps to prevent or reduce PSP in future red tide season include better monitoring of red tide occurrence, regular sampling of shellfish for determination of STX level, wider dissemination of information on the danger of eating contaminated shellfish among the communities, fishermen, and fishmongers.


Assuntos
Saxitoxina/envenenamento , Intoxicação por Frutos do Mar/diagnóstico , Adolescente , Adulto , Idoso , Alveolados , Animais , Bioensaio , Criança , Contaminação de Alimentos/análise , Humanos , Malásia , Pessoa de Meia-Idade , Estações do Ano , Água do Mar/microbiologia , Água do Mar/parasitologia , Frutos do Mar/análise , Adulto Jovem
4.
Crit Rev Toxicol ; 46(5): 385-419, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26923223

RESUMO

Cyanobacteria are ubiquitous photosynthetic micro-organisms forming blooms and scums in surface water; among them some species can produce cyanotoxins giving rise to some concern for human health and animal life. To date, more than 65 cyanobacterial neurotoxins have been described, of which the most studied are the groups of anatoxins and saxitoxins (STXs), comprising many different variants. In freshwaters, the hepatotoxic microcystins represent the most frequently detected cyanotoxin: on this basis, it could appear that neurotoxins are less relevant, but the low frequency of detection may partially reflect an a priori choice of target analytes, the low method sensitivity and the lack of certified standards. Cyanobacterial neurotoxins target cholinergic synapses or voltage-gated ion channels, blocking skeletal and respiratory muscles, thus leading to death by respiratory failure. This review reports and analyzes the available literature data on environmental occurrence of cyanobacterial neurotoxic alkaloids, namely anatoxins and STXs, their biosynthesis, toxicology and epidemiology, derivation of guidance values and action limits. These data are used as the basis to assess the risk posed to human health, identify critical exposure scenarios and highlight the major data gaps and research needs.


Assuntos
Toxinas Bacterianas/análise , Toxinas Marinhas/análise , Microcistinas/análise , Neurotoxinas/análise , Saxitoxina/análise , Animais , Toxinas Bacterianas/envenenamento , Toxinas Bacterianas/toxicidade , Cianobactérias/química , Cianobactérias/metabolismo , Humanos , Toxinas Marinhas/envenenamento , Toxinas Marinhas/toxicidade , Microcistinas/envenenamento , Microcistinas/toxicidade , Neurotoxinas/envenenamento , Neurotoxinas/toxicidade , Medição de Risco , Saxitoxina/envenenamento , Saxitoxina/toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-26306212

RESUMO

BACKGROUND: In July 2013, the Philippines' Event-Based Surveillance & Response Unit received a paralytic shellfish poisoning (PSP) report from Tarangnan, Western Samar. A team from the Department of Health conducted an outbreak investigation to identify the implicated source and risk factors in coastal villages known for green mussel production and exportation. METHODS: A case was defined as a previously well individual from Tarangan, Western Samar who developed gastrointestinal symptoms and any motor and/or sensory symptoms after consumption of shellfish from 29 June to 4 July 2013 in the absence of any known cause. The team reviewed medical records, conducted active case finding and a case-control study. Relatives of cases who died were interviewed. Sera and urine specimens, green mussel and seawater samples were tested for saxitoxin levels using high performance liquid chromatography. RESULTS: Thirty-one cases and two deaths were identified. Consumption of > 1 cup of green mussel broth was associated with being a case. Seawater sample was positive for Pyrodinium bahamense var. compressum and green mussel samples were positive for saxitoxin. Inspection revealed villagers practice open defecation and improper garbage disposal. CONCLUSION: This PSP outbreak was caused by the consumption of the green mussel broth contaminated by saxitoxin. As a result of this outbreak, dinoflagellate and saxitoxin surveillance was established, and since the outbreak, there have been no harmful algal blooms event or PSP case reported since. A "Save Cambatutay Bay" movement, focusing on proper waste disposal practice and clean-up drives has been mobilized.


Assuntos
Bivalves , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar/etiologia , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Dinoflagelados/isolamento & purificação , Surtos de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Saxitoxina/análise , Água do Mar/parasitologia , Adulto Jovem
6.
West J Emerg Med ; 15(4): 378-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25035737

RESUMO

We describe a case series of seven patients presenting to an emergency department with symptoms of paralytic shellfish poisoning. They developed varying degrees of nausea, vomiting, diarrhea, weakness, ataxia and paresthesias after eating mussels harvested from a beach near their resort. Four patients were admitted to the hospital, one due to increasing respiratory failure requiring endotracheal intubation and the remainder for respiratory monitoring. All patients made a full recovery, most within 24 hours. The ability to recognize and identify paralytic shellfish poisoning and manage its complications are important to providers of emergency medicine.


Assuntos
Bivalves , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar/diagnóstico , Intoxicação por Frutos do Mar/terapia , Adolescente , Adulto , Idoso , Animais , Serviço Hospitalar de Emergência , Feminino , Humanos , Hipopotassemia/diagnóstico , Hipopotassemia/etiologia , Unidades de Terapia Intensiva , Masculino
8.
Mol Biol Evol ; 28(3): 1173-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21076133

RESUMO

The recent determination of the genetic basis for the biosynthesis of the neurotoxin, saxitoxin, produced by cyanobacteria, has revealed a highly complex sequence of reactions, involving over 30 biosynthetic steps encoded by up to 26 genes clustered at one genomic locus, sxt. Insights into evolutionary-ecological processes have been found through the study of such secondary metabolites because they consist of a measurable phenotype with clear ecological consequences, synthesized by known genes in a small number of species. However, the processes involved in and timing of the divergence of prokaryotic secondary metabolites have been difficult to determine due to their antiquity and the possible frequency of horizontal gene transfer and homologous recombination. Through analyses of gene synteny, phylogenies of individual genes, and analyses of recombination and selection, we identified the evolutionary processes of this cluster in five species of cyanobacteria. Here, we provide evidence that the sxt cluster appears to have been largely vertically inherited and was therefore likely present early in the divergence of the Nostocales, at least 2,100 Ma, the earliest reliably dated appearance of a secondary metabolite. The sxt cluster has been extraordinarily conserved through stabilizing selection. Genes have been lost and rearranged, have undergone intra- and interspecific recombination, and have been subject to duplication followed by positive selection along the duplicated lineage, with likely consequences for the toxin analogues produced. Several hypotheses exist as to the ecophysiological role of saxitoxin: as a method of chemical defense, cellular nitrogen storage, DNA metabolism, or chemical signaling. The antiquity of this gene cluster indicates that potassium channels, not sodium channels, may have been the original targets of this compound. The extraordinary conservation of the machinery for saxitoxin synthesis, under radically changing environmental conditions, shows that it has continued to play an important adaptive role in some cyanobacteria.


Assuntos
Sequência Conservada/genética , Neurotoxinas/genética , Saxitoxina/genética , Animais , Cianobactérias/classificação , Cianobactérias/genética , Evolução Molecular , Deleção de Genes , Duplicação Gênica , Genes Bacterianos/fisiologia , Humanos , Família Multigênica , Neurotoxinas/biossíntese , Neurotoxinas/classificação , Neurotoxinas/envenenamento , Filogenia , Bloqueadores dos Canais de Potássio/metabolismo , Bloqueadores dos Canais de Potássio/envenenamento , Canais de Potássio/metabolismo , Recombinação Genética , Saxitoxina/biossíntese , Saxitoxina/classificação , Saxitoxina/envenenamento , Seleção Genética , Alinhamento de Sequência , Análise de Sequência de DNA , Sintenia/genética
9.
Toxicon ; 56(2): 108-22, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20035780

RESUMO

Paralytic shellfish poisoning (PSP) is the foodborne illness associated with the consumption of seafood products contaminated with the neurotoxins known collectively as saxitoxins (STXs). This family of neurotoxins binds to voltage-gated sodium channels, thereby attenuating action potentials by preventing the passage of sodium ions across the membrane. Symptoms include tingling, numbness, headaches, weakness and difficulty breathing. Medical treatment is to provide respiratory support, without which the prognosis can be fatal. To protect human health, seafood harvesting bans are in effect when toxins exceed a safe action level (typically 80 microg STX eq 100 g(-1) tissue). Though worldwide fatalities have occurred, successful management and monitoring programs have minimized PSP cases and associated deaths. Much is known about the toxin sources, primarily certain dinoflagellate species, and there is extensive information on toxin transfer to traditional vectors - filter-feeding molluscan bivalves. Non-traditional vectors, such as puffer fish and lobster, may also pose a risk. Rapid and reliable detection methods are critical for toxin monitoring in a wide range of matrices, and these methods must be appropriately validated for regulatory purposes. This paper highlights PSP seafood safety concerns, documented human cases, applied detection methods as well as monitoring and management strategies for preventing PSP-contaminated seafood products from entering the food supply.


Assuntos
Neurotoxinas/envenenamento , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar/etiologia , Animais , Dinoflagelados/metabolismo , Monitoramento Ambiental , Cadeia Alimentar , Contaminação de Alimentos/análise , Humanos , Neurotoxinas/análise , Neurotoxinas/metabolismo , Saxitoxina/análise , Saxitoxina/metabolismo , Alimentos Marinhos/envenenamento , Intoxicação por Frutos do Mar/metabolismo , Bloqueadores dos Canais de Sódio/envenenamento , Canais de Sódio/efeitos dos fármacos
10.
Mar Drugs ; 6(2): 308-48, 2008 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-18728730

RESUMO

Paralytic shellfish poisoning (PSP), due to saxitoxin and related compounds, typically results from the consumption of filter-feeding molluscan shellfish that concentrate toxins from marine dinoflagellates. In addition to these microalgal sources, saxitoxin and related compounds, referred to in this review as STXs, are also produced in freshwater cyanobacteria and have been associated with calcareous red macroalgae. STXs are transferred and bioaccumulate throughout aquatic food webs, and can be vectored to terrestrial biota, including humans. Fisheries closures and human intoxications due to STXs have been documented in several non-traditional (i.e. non-filter-feeding) vectors. These include, but are not limited to, marine gastropods, both carnivorous and grazing, crustacea, and fish that acquire STXs through toxin transfer. Often due to spatial, temporal, or a species disconnection from the primary source of STXs (bloom forming dinoflagellates), monitoring and management of such non-traditional PSP vectors has been challenging. A brief literature review is provided for filter feeding (traditional) and non-filter feeding (non-traditional) vectors of STXs with specific reference to human effects. We include several case studies pertaining to management actions to prevent PSP, as well as food poisoning incidents from STX(s) accumulation in non-traditional PSP vectors.


Assuntos
Cadeia Alimentar , Paralisia/etiologia , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar , Animais , Eutrofização , Humanos , Saúde Pública , Alimentos Marinhos/envenenamento
11.
Adv Exp Med Biol ; 619: 613-37, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18461786

RESUMO

Poisoning of livestock by toxic cyanobacteria was first reported in the 19th century, and throughout the 20th century cyanobacteria-related poisonings of livestock and wildlife in all continents have been described. Some mass mortality events involving unrelated fauna in prehistoric times have also been attributed to cyanotoxin poisoning; if correct, this serves as a reminder that toxic cyanobacteria blooms predate anthropogenic manipulation of the environment, though there is probably general agreement that human intervention has led to increases in the frequency and extent of cyanobacteria blooms. Many of the early reports of cyanobacteria poisoning were anecdotal and circumstantial, albeit with good descriptions of the appearance and behaviour of cyanobacteria blooms that preceded or coincided with illness and death in exposed animals. Early necropsy findings of hepatotoxicity were subsequently confirmed by experimental investigations. More recent reports supplement clinical and post-mortem findings with investigative chemistry techniques to identify cyanotoxins in stomach contents and tissue fluids.


Assuntos
Toxinas Bacterianas/envenenamento , Cianobactérias/patogenicidade , Eutrofização , Toxinas Marinhas/envenenamento , Microcistinas/envenenamento , Alcaloides , Animais , Animais Domésticos/microbiologia , Animais Selvagens/microbiologia , Toxinas Bacterianas/história , Aves/microbiologia , História do Século XX , História do Século XXI , História Antiga , Toxinas Marinhas/história , Microcistinas/história , Peptídeos Cíclicos/história , Peptídeos Cíclicos/envenenamento , Saxitoxina/história , Saxitoxina/envenenamento , Tropanos/história , Tropanos/envenenamento , Uracila/análogos & derivados , Uracila/história , Uracila/envenenamento
12.
Emerg Med Clin North Am ; 25(2): 549-66; abstract xi, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17482032

RESUMO

Emergency personnel are tasked with the daunting job of being the first to evaluate and manage victims of a terrorist attack. Numerous potential chemical agents could be used by terrorists. The challenge for first responders and local hospital emergency personnel is to prepare for a terrorist event that might use one or more of these agents. As part of that preparation, emergency physicians should have a basic understanding of potential chemical terrorist agents. It is beyond the scope of this article to review all potential terrorist agents. Rather, four potential agents have been chosen for review: sodium monofluoroacetate, trichothecene mycotoxins, vomiting agents, and saxitoxin.


Assuntos
Terrorismo Químico , Planejamento em Desastres , Serviço Hospitalar de Emergência/organização & administração , Fluoracetatos/envenenamento , Envenenamento/fisiopatologia , Rodenticidas/envenenamento , Saxitoxina/envenenamento , Tricotecenos/envenenamento , Humanos , Envenenamento/diagnóstico , Envenenamento/terapia
13.
Environ Health Perspect ; 114(10): 1502-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17035133

RESUMO

BACKGROUND: From January 2002 to May 2004, 28 puffer fish poisoning (PFP) cases in Florida, New Jersey, Virginia, and New York were linked to the Indian River Lagoon (IRL) in Florida. Saxitoxins (STXs) of unknown source were first identified in fillet remnants from a New Jersey PFP case in 2002. METHODS: We used the standard mouse bioassay (MBA), receptor binding assay (RBA), mouse neuroblastoma cytotoxicity assay (MNCA), Ridascreen ELISA, MIST Alert assay, HPLC, and liquid chromatography-mass spectrometry (LC-MS) to determine the presence of STX, decarbamoyl STX (dc-STX), and N-sulfocarbamoyl (B1) toxin in puffer fish tissues, clonal cultures, and natural bloom samples of Pyrodinium bahamense from the IRL. RESULTS: We found STXs in 516 IRL southern (Sphoeroides nephelus), checkered (Sphoeroides testudineus), and bandtail (Sphoeroides spengleri) puffer fish. During 36 months of monitoring, we detected STXs in skin, muscle, and viscera, with concentrations up to 22,104 microg STX equivalents (eq)/100 g tissue (action level, 80 microg STX eq/100 g tissue) in ovaries. Puffer fish tissues, clonal cultures, and natural bloom samples of P. bahamense from the IRL tested toxic in the MBA, RBA, MNCA, Ridascreen ELISA, and MIST Alert assay and positive for STX, dc-STX, and B1 toxin by HPLC and LC-MS. Skin mucus of IRL southern puffer fish captive for 1-year was highly toxic compared to Florida Gulf coast puffer fish. Therefore, we confirm puffer fish to be a hazardous reservoir of STXs in Florida's marine waters and implicate the dinoflagellate P. bahamense as the putative toxin source. CONCLUSIONS: Associated with fatal paralytic shellfish poisoning (PSP) in the Pacific but not known to be toxic in the western Atlantic, P. bahamense is an emerging public health threat. We propose characterizing this food poisoning syndrome as saxitoxin puffer fish poisoning (SPFP) to distinguish it from PFP, which is traditionally associated with tetrodotoxin, and from PSP caused by STXs in shellfish.


Assuntos
Dinoflagelados/química , Envenenamento/epidemiologia , Saxitoxina/envenenamento , Takifugu , Animais , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Humanos , Toxinas Marinhas/envenenamento , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Estados Unidos/epidemiologia
14.
Wei Sheng Yan Jiu ; 35(4): 435-8, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16986518

RESUMO

OBJECTIVE: Paralytic shellfish poisoning (PSP) and diarrhetic shellfish poisoning (DSP) in 7 species of economical shellfishes were analyzed for 1 year, which collected from Huangsha seafood market of Guangzhou from Apr, 2004 to Mar, 2005. METHODS: The levels of PSP and DSP in bivalves were determined with mouse bioassay of AOAC. The risk assessment of PSP and DSP in bivalves was conducted according to FAO and Chinese Administration Organization of Fish Culture and Seaport. RESULTS: PSP was detected in 2 species of the shellfishes assayed and DSP was found out in 6 species. The content of PSP was lower than 4MU/g tissue, whereas the level of PSP in glands was higher than in muscles. DSP toxin was detected in 36 samples of 6 species, what is more, DSP level in 10 samples exceeded the safety threshold. The levels in PSP and DSP of bivalves were all higher in spring and winter with some characteristic of season. CONCLUSION: The results suggested that PSP in economical shellfish in Guangzhou market was lower, and shellfish was safe to eat in term of the PSP level if glands were discarded, but DSP contamination in bivalves was severe. It is essential to detect and assess the risk of DSP and PSP in bivalves from seafood market in the future.


Assuntos
Contaminação de Alimentos/análise , Toxinas Marinhas/análise , Saxitoxina/análise , Intoxicação por Frutos do Mar/complicações , Frutos do Mar/análise , Animais , Bivalves , Diarreia/etiologia , Toxinas Marinhas/envenenamento , Camundongos , Paralisia/induzido quimicamente , Paralisia/etiologia , Saxitoxina/envenenamento
15.
Food Addit Contam ; 22(7): 647-51, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16019840

RESUMO

This paper reports the results of investigations of shellfish toxin contamination of products obtained from Shanghai seafood markets. From May to October 2003, 66 samples were collected from several major seafood markets. Paralytic shellfish poisoning (PSP) and diarrhetic shellfish poisoning (DSP) toxins in shellfish samples were monitored primarily by a mouse bioassay, then analysed by HPLC for the chemical contents of the toxins. According to the mouse bioassay, eight samples were detected to be contaminated by PSP toxins and seven samples were contaminated by DSP toxins. Subsequent HPLC analysis indicated that the concentrations of the PSP toxins ranged from 0.2 to 1.9 microg/100 g tissues and the main components were gonyautoxins 2/3 (GTX2/3). As for DSP, okadaic acid was detected in three samples, and its concentration ranged from 3.2 to 17.5 microg/100 g tissues. Beside okadaic acid, its analogues, dinophysistoxins (DTX1), were found in one sample. According to the results, gastropod (Neverita didyma) and scallop (Argopecten irradians) were more likely contaminated with PSP and DSP toxins, and most of the contaminated samples were collected from Tongchuan and Fuxi markets. In addition, the contaminated samples were always found in May, June and July. Therefore, consumers should be cautious about eating the potential toxic shellfish during this specific period.


Assuntos
Contaminação de Alimentos , Toxinas Marinhas/análise , Frutos do Mar/análise , Animais , Bioensaio/métodos , China , Cromatografia Líquida de Alta Pressão/métodos , Diarreia/induzido quimicamente , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/envenenamento , Toxinas Marinhas/envenenamento , Camundongos , Ácido Okadáico/análogos & derivados , Ácido Okadáico/análise , Paralisia/induzido quimicamente , Saxitoxina/análogos & derivados , Saxitoxina/análise , Saxitoxina/envenenamento
16.
Rev. biol. trop ; 52(supl.1): 89-98, sept. 2004. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-450543

RESUMO

A severe outbreak of Paralytic Shellfish Poisoning (PSP) occurred in Manzanillo and Guayacán, northwestern coast of Margarita Island, Venezuela, between August and October 1991. A bloom of dinoflagellates including Prorocentrum gracile, Gymnodinium catenatum and Alexandrium tamarense seemed to be responsible for this outbreak. Levels of PSP toxins in mussels (Perna perna) exceeded the international safety limit of saxitoxin, 80 µg STX/100 g meat. PSP toxin values varied between 2 548 and 115 µg STX/100 g meat in Manzanillo, and between 1 422 and 86 µg STX/100 g meat in Guayacán. At both locations, the highest levels were detected in August, when 24 patients exhibited typical symptoms of PSP toxicity after consuming cooked mussels (16 required hospitalization). A high pressure liquid chromatographic (HPLC) procedure was recently used on the 1991 samples. The major toxin detected in samples of both locations was decarbamoyl saxitoxin (dcSTX), but low concentrations of saxitoxin were also found in Manzanillo samples. Gonyautoxins GTX1, GTX2 and GTX3 were detected only at Guayacán, while in both locations, decarbamoylgonyatouxin (dcGTX2,3) toxins were detected. These findings represent the first time that causative toxins of PSP in Venezuela have been chemically identified, and confirm the presence of dcSTX and dcGTX in mussels from the Caribbean Sea. The presence of dcSTX and dcGTX in shellfish is indicative that Gymnodinium catenatum was a causative organism for outbreak of PSP


Un severo brote de intoxicación paralizante por moluscos (PSP en inglés) ocurrió en Manzanillo y Guayacán en la costa noroeste de la Isla de Margarita, Venezuela entre agosto y octubre de 1991. Una proliferación de Prorocentrum gracile, Gymnodinium catenatum y Alexandrium tamarense causó el brote. Los niveles de PSP en mejillón (Perna perna) superaron los niveles máximos permisibles de saxitoxina, 80 µg STX/100g carne. Los niveles de toxinas variaron entre 2 548 y 115 µg STX/100 g carne en Manzanillo y entre 1 422 y 86 µg STX/100g carne en Guayacán. En ambas localidades, los máximos niveles se detectaron en agosto, cuando 24 personas presentaron síntomas típicos de PSP después de consumir mejillones cocidos (16 fueron hospitalizados). Se aplicó recientemente cromatografía líquida de alta presión (HPLC) a muestras del año 1991 y la toxina más detectada fue decarbamoyl saxitoxina (dcSTX), pero también se encontró saxitoxinas en muestras de Manzanillo. Las gonyautoxinas GTX1, GTX2 y GTX3 solo se encontraron en Guayacán; en ambas localidades se detectó decarbamoylgonyatouxin (dcGTX2,3). Estos hallazgos representan la primera vez que las toxinas causantes de un brote de PSP en Venezuela han sido químicamente identificadas, confirmando la presencia de dcSTX y dcGTX en mejillones del mar Caribe. La presencia de dcSTX y dcGTX en moluscos, indica que G. catenatum fue el organismo responsable de la intoxicación


Assuntos
Humanos , Animais , Ratos , Bivalves/química , Intoxicação por Ciguatera/epidemiologia , Dinoflagelados/crescimento & desenvolvimento , Eutrofização/fisiologia , Saxitoxina/envenenamento , Frutos do Mar/envenenamento , Bivalves/metabolismo , Cromatografia Líquida de Alta Pressão , Intoxicação por Ciguatera/metabolismo , Surtos de Doenças , Dinoflagelados/química , Dinoflagelados/classificação , Monitoramento Ambiental , Fluorescência , Saxitoxina/análise , Saxitoxina/metabolismo , Frutos do Mar/análise , Fatores de Tempo , Venezuela/epidemiologia
17.
Toxicon ; 43(2): 149-58, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15019474

RESUMO

In July 5, 2002 fishermen working in harvesting sea urchin (Loxechinus albus) in the Patagonia Chilean fjords were intoxicated by consumption of filter-feeder bivalve Aulacomya ater. After the ingestion of 7-9 ribbed mussel, two fishermen died 3-4 h after shellfish consumption. The forensic examination in both victims did not show pathological abnormalities with the exception of the lungs conditions, crackling to the touch, pulmonary congestion and edema. The toxic mussel sample showed a toxicity measured by mouse bioassay of 8575 microg of STX (saxitoxin) equivalent by 100 g of shellfish meat. Using post-column derivatization HPLC method with fluorescent on line detection was possible to measure mass amount of each paralytic shellfish poisoning (PSP) toxin yielding individual toxin concentrations. These PSP toxins were identified in the gastric content, body fluids (urine, bile and cerebrospinal fluid) and tissue samples (liver, kidney, lung, stomach, spleen, heart, brain, adrenal glands, pancreas and thyroids glands). The toxin profiles of each body fluid and tissue samples and the amount of each PSP toxin detected are reported. The PSP toxins found in the gastric content, were STX and the gonyautoxins (GTX4, GTX1, GTX5, GTX3 and GTX2) which showed to be the major amount of PSP toxins found in the victims biological samples. The PSP toxin composition in urine and bile showed as major PSP toxins neoSaxitoxin (neoSTX) and GTX4/GTX1 epimers, both STX analogues with an hydroxyl group (-OH) in the N(1) of the tetrahydropurine nucleus. The neoSTX was not present in the gastric content sample, indicating that the oxidation of N(1) in the STX tetrahydropurine nucleus resulted neoSTX, in a similar way that GTX3/GTX2 epimers were transformed in GTX4/GTX1 epimers. Beside this metabolic transformation, also the hydrolysis of carbamoyl group from STX to form its decarbomoyl analogue decarbamoylsaxitoxin was detected in liver, kidney and lung. These two findings show that PSP toxins went under metabolic transformation during the 3-4 h of human intoxication period, in which PSP toxins showed enzymatic oxidation of N(1) in the tetrahydropurine nucleus, producing neoSTX and GTX4/GTX1 epimers starting from STX and GTX3/GTX2 epimers, respectively. This study conclude, that PSP toxins are metabolically transformed by humans and that they are removed from the body by excretion in the urine and feces like any other xenobiotic compound.


Assuntos
Bivalves/química , Toxinas Marinhas/envenenamento , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar , Animais , Chile , Cromatografia Líquida de Alta Pressão , Evolução Fatal , Humanos , Toxinas Marinhas/metabolismo , Toxinas Marinhas/farmacocinética , Saxitoxina/análogos & derivados , Saxitoxina/metabolismo , Saxitoxina/farmacocinética , Frutos do Mar/análise
18.
Rev Biol Trop ; 52 Suppl 1: 89-98, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17465121

RESUMO

A severe outbreak of Paralytic Shellfish Poisoning (PSP) occurred in Manzanillo and Guayacán, northwestern coast of Margarita Island, Venezuela, between August and October 1991. A bloom of dinoflagellates including Prorocentrum gracile, Gymnodinium catenatum and Alexandrium tamarense seemed to be responsible for this outbreak. Levels of PSP toxins in mussels (Perna perna) exceeded the international safety limit of saxitoxin, 80 microg STX/100 microg meat. PSP toxin values varied between 2548 and 115 microg STX/100 g meat in Manzanillo, and between 1422 and 86 microg STX/100 g meat in Guayacán. At both locations, the highest levels were detected in August, when 24 patients exhibited typical symptoms of PSP toxicity after consuming cooked mussels (16 required hospitalization). A high pressure liquid chromatographic (HPLC) procedure was recently used on the 1991 samples. The major toxin detected in samples of both locations was decarbamoyl saxitoxin (dcSTX), but low concentrations of saxitoxin were also found in Manzanillo samples. Gonyautoxins GTX1, GTX2 and GTX3 were detected only at Guayacán, while in both locations, decarbamoylgonyatouxin (dcGTX2,3) toxins were detected. These findings represent the first time that causative toxins of PSP in Venezuela have been chemically identified, and confirm the presence of dcSTX and dcGTX in mussels from the Caribbean Sea. The presence of dcSTX and dcGTX in shellfish is indicative that Gymnodinium catenatum was a causative organism for outbreak of PSP.


Assuntos
Bivalves/química , Intoxicação por Ciguatera/epidemiologia , Dinoflagelados/crescimento & desenvolvimento , Eutrofização , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar , Animais , Bivalves/metabolismo , Cromatografia Líquida de Alta Pressão , Intoxicação por Ciguatera/metabolismo , Dinoflagelados/química , Dinoflagelados/classificação , Surtos de Doenças , Monitoramento Ambiental , Monitoramento Epidemiológico , Humanos , Ratos , Saxitoxina/análise , Saxitoxina/metabolismo , Frutos do Mar/análise , Fatores de Tempo , Venezuela/epidemiologia
19.
Toxicon ; 40(10): 1463-69, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12368116

RESUMO

After ingestion of a specimen of the crab Zosimus aeneus (Xanthidae), an East Timorese adult male died within several hours. Xanthid crabs are known to harbour paralytic shellfish toxins (PSTs), tetrodotoxin and palytoxin. A post-mortem examination did not find any obvious pathological abnormalities. This absence of pathologies is more often associated with PSTs and tetrodotoxin intoxication. A second, yet uneaten specimen of Z. aeneus from the same meal, contained a significant amount of PSTs and these same toxins were identified in the gut contents, blood, liver and urine of the victim. Metabolism of the PSTs occurred with the ingested crab harbouring gonyautoxin 2, gonyautoxin 3 and saxitoxin (STX) whereas neoSTX, decarbamoylSTX and STX dominated the PSTs in the victim's urine. The PST composition in the gut contents, in both their identity and proportion, was intermediate between the eaten crab and the urine suggesting that toxin conversion commenced in the victim's gut. The dose consumed by the victim was calculated to be between 1 and 2 microg STX equivalents/kg based upon the concentration in the remains of the cooked crab. The victim's meal did not consist solely of the toxic crab eaten and the possibility of other food items acting in a synergistic manner with the consumed PSTs cannot be discounted.


Assuntos
Braquiúros/química , Saxitoxina/envenenamento , Intoxicação por Frutos do Mar , Adulto , Proteínas de Anfíbios , Animais , Bioensaio , Proteínas de Transporte/metabolismo , Cromatografia Líquida de Alta Pressão , Evolução Fatal , Humanos , Indonésia , Masculino , Saxitoxina/análise , Saxitoxina/metabolismo
20.
Med J Aust ; 175(1): 29-31, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11476199

RESUMO

Paralytic shellfish poisoning (PSP) is a serious illness in which neurological symptoms predominate. Recovery is usually complete and uncomplicated, but in severe cases there may be respiratory paralysis and death. Most cases follow consumption of bivalve molluscs that have filter-fed on toxic marine microalgae (phytoplankton). Microalgae capable of causing the intoxication have been recorded in all States of Australia, and major toxic blooms have occurred in Tasmania, Victoria and South Australia.


Assuntos
Doenças Transmitidas por Alimentos , Saúde Pública , Saxitoxina/envenenamento , Frutos do Mar , Adulto , Criança , Pré-Escolar , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/mortalidade , Doenças Transmitidas por Alimentos/terapia , Humanos , Saxitoxina/farmacocinética
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