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1.
Mar Drugs ; 17(1)2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30597874

RESUMO

Historical records of ciguatera in Mexico date back to 1862. This review, including references and epidemiological reports, documents 464 cases during 25 events from 1984 to 2013: 240 (51.72%) in Baja California Sur, 163 (35.12%) in Quintana Roo, 45 (9.69%) in Yucatan, and 16 (3.44%) cases of Mexican tourists intoxicated in Cuba. Carnivorous fish, such as snapper (Lutjanus) and grouper (Epinephelus and Mycteroperca) in the Pacific Ocean, and great barracuda (Sphyraena barracuda) and snapper (Lutjanus) in the Atlantic (Gulf of Mexico and Caribbean Sea), were involved in all cases. In the Mexican Caribbean, a sub-record of ciguatera cases that occurred before 1984 exists. However, the number of intoxications has increased in recent years, and this food poisoning is poorly studied in the region. Current records suggest that ciguatera fish poisoning in humans is the second most prevalent form of seafood poisoning in Mexico, only exceeded by paralytic shellfish poisoning (505 cases, 21 fatalities in the same 34-year period). In this study, the status of ciguatera in Mexico (epidemiological and treatment), and the fish vectors are reviewed. Dinoflagellate species Gambierdiscus, Ostreopsis, and Prorocentrum are related with the reported outbreaks, marine toxins, ecological risk, and the potential toxicological impact.


Assuntos
Intoxicação por Ciguatera/epidemiologia , Ciguatoxinas/química , Animais , Peixes , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , México/epidemiologia , Alimentos Marinhos/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-25565135

RESUMO

The paralytic shellfish toxin (PST) profiles of Gymnodinium catenatum Graham have been reported for several strains from the Pacific coast of Mexico cultured under different laboratory conditions, as well as from natural populations. Up to 15 saxitoxin analogues occurred and the quantity of each toxin depended on the growth phase and culture conditions. Previous analysis of toxin profiles of G. catenatum isolated from Mexico have been based on post-column oxidation liquid chromatography with fluorescence detection (LC-FLD), a method prone to artefacts and non-specificity, leading to misinterpretation of toxin composition. We describe, for the first time, the complete toxin profile for several G. catenatum strains from diverse locations of the Pacific coast of Mexico. The new results confirmed previous reports on the dominance of the less potent sulfocarbamoyl toxins (C1/2); significant differences, however, in the composition (e.g., absence of saxitoxin, gonyautoxin 2/3 and neosaxitoxin) were revealed in our confirmatory analysis. The LC-MS/MS analyses also indicated at least seven putative benzoyl toxin analogues and provided support for their existence. This new toxin profile shows a high similarity (> 80%) to the profiles reported from several regions around the world, suggesting low genetic variability among global populations.


Assuntos
Dinoflagelados/química , Saxitoxina/análogos & derivados , Cromatografia Líquida de Alta Pressão , México , Saxitoxina/análise , Espectrometria de Massas em Tandem
3.
Toxicon ; 90: 199-212, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25151371

RESUMO

The effects of temperature on growth, cell toxicity, toxin content, and profile of paralytic shellfish toxins was determined in eight isolates of Gymnodinium catenatum from several localities along the Pacific Coast of Mexico. The isolates were cultivated in modified f/2 media with Se (10(-8) M), and a reduced concentration of Cu (10(-8) M), under a 12 h:12 h day-night cycle with an irradiance of 150 µE m(-2) s(-1). Isolates were progressively adapted for three generations to each of the temperatures (16, 19, 22, 24, 27, 30, and 33 °C). The cultures were grown in 125 mL Erlenmeyer flasks with 60 mL of media and harvested by filtration in late exponential growth. Toxins were analyzed by HPLC with a post-column oxidation and fluorescent detection (FLD). G. catenatum isolates tolerate temperatures between 16 and 33 °C, with maximum growth rates of 0.32 and 0.39 div day(-1) at 21 °C and 24 °C, respectively; maximum cell densities of 4700 and 5500 cells mL(-1) were obtained at 27 and 21 °C, respectively. No effect of toxicity per cell with temperature was observed, varying between 10.10 and 28.19 pgSXTeq cell(-1). Ten saxitoxin analogues were detected in all isolates, observing changes in the toxin profile with temperature. C1/2 toxins decreased from 80% mol at 16 °C to 20% mol at 33 °C, B1/2 toxins increased from 19% mol at 16 °C to 42% mol at 33 °C, and decarbamoyl toxins were more abundant at 21 °C. These results show that G. catenatum isolates from different regions of the Pacific coast of Mexico have a similar response to temperature and that this parameter can modify growth rate, cell density, and toxin profile of the species, particularly the decarbamoyl and sulfocarbamoyl toxins.


Assuntos
Dinoflagelados/crescimento & desenvolvimento , Dinoflagelados/metabolismo , Toxinas Marinhas/metabolismo , Água do Mar , Temperatura
4.
Mar Drugs ; 10(2): 329-39, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22412804

RESUMO

The toxin content in various life cycle stages of tank-cultivated bullseye puffer (Sphoeroides annulatus) were analyzed by mouse bioassay and ESI-MS spectrometry analysis. The presence of toxin content was determined in extracts of sperm, eggs, embryo, larvae, post-larvae, juvenile, pre-adult, and adult fish, as well as in food items used during the cultivation of the species. Our findings show that only the muscle of juveniles, the viscera of pre-adults, and muscle, liver, and gonad of adult specimens were slightly toxic (<1 mouse unit). Thus, cultivated S. annulatus, as occurs with other cultivated puffer fish species, does not represent a food safety risk to consumers. This is the first report of toxin analysis covering the complete life stages of a puffer fish under controlled conditions.


Assuntos
Inocuidade dos Alimentos , Estágios do Ciclo de Vida , Alimentos Marinhos/efeitos adversos , Tetraodontiformes/crescimento & desenvolvimento , Tetraodontiformes/metabolismo , Tetrodotoxina/metabolismo , Animais , Aquicultura , Bioensaio , Feminino , Masculino , México , Camundongos , Camundongos Endogâmicos , Alimentos Marinhos/análise , Espectrometria de Massas por Ionização por Electrospray , Tetraodontiformes/embriologia , Tetrodotoxina/análise , Tetrodotoxina/química , Tetrodotoxina/toxicidade
5.
J Environ Biol ; 32(4): 407-12, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22315820

RESUMO

A Microcoleus chthonoplastes strain SC7B9002-1 isolated from microbial mats in tidal channels from San Carlos, Baja California Sur, Mexico was subjected to short- (15 days) and long-term (2 years) conservation assays in liquid nitrogen (-196 degrees C) using cryoprotective agents, such as 5% DMSO, 20% PVP-40, and 20% glycerol. Survival rate, chlorophyll a, protein, and nucleic acids content were observed in each case. Interesting growth and a significant increase in protein content was observed when no cryoprotectant was used during liquid nitrogen immersion. In the absence of a cryoprotectant, M. chthonoplastes lost their typical shape resembled spheroplasts, and recovery cultivation times after freezing were 5 and 25 days (short and long-term, respectively). Recovery from long-term preservation with 5% DMSO took 15 days. PVP and glycerol did not allow recovery of viable cells. The survival of M. chthonoplastes to freezing without cryoprotectant and the adaptive mechanisms that allow surviving under freezing conditions are discussed.


Assuntos
Crioprotetores , Cianobactérias/fisiologia , Congelamento , Sobrevivência Celular
6.
J Environ Biol ; 32(4): 413-23, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22315821

RESUMO

Historical documents and classic works together with recent specialized literature have described Harmful Algal Blooms (HABs) in the Gulf of California. This is a review of HABs impact (qualitative and quantitative) during the last decades in the Gulf of California on wild (mammals, birds, fishes, and invertebrates) and cultured animals (shrimps and fishes). Microalgal species responsible of noxious effects are Noctiluca scintillans, Cochlodinium polykrikoides, Gymnodinium catenatum, Prorocentrum minimum, Akashiwo sanguinea, Chattonella subsalsa Ch. marina, Chattonella sp., Heterocapsa sp., Dinophysis sp., Fibrocapsa japonica, Heterosigma akashiwo, Thalassiosira sp., Chaetoceros spp., Pseudo-nitzschia australis, P fraudulenta, Pseudo-nitzschia sp., Trichodesmium erythraeum and ScSchizotrix calcicola. Emphasis is given to the necessity to continue with interdisciplinary studies in oceanography, ecology, toxicology and toxinology interrelated with biomedical sciences such as physiology, pathology, epidemiology and animal health.


Assuntos
Animais Selvagens , Aquicultura , Proliferação Nociva de Algas/fisiologia , Animais , Oceano Pacífico
7.
Mar Drugs ; 8(6): 1935-61, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20631876

RESUMO

This review presents a detailed analysis of the state of knowledge of studies done in Mexico related to the dinoflagellate Gymnodinium catenatum, a paralytic toxin producer. This species was first reported in the Gulf of California in 1939; since then most studies in Mexico have focused on local blooms and seasonal variations. G. catenatum is most abundant during March and April, usually associated with water temperatures between 18 and 25 °C and an increase in nutrients. In vitro studies of G. catenatum strains from different bays along the Pacific coast of Mexico show that this species can grow in wide ranges of salinities, temperatures, and N:P ratios. Latitudinal differences are observed in the toxicity and toxin profile, but the presence of dcSTX, dcGTX2-3, C1, and C2 are usual components. A common characteristic of the toxin profile found in shellfish, when G. catenatum is present in the coastal environment, is the detection of dcGTX2-3, dcSTX, C1, and C2. Few bioassay studies have reported effects in mollusks and lethal effects in mice, and shrimp; however no adverse effects have been observed in the copepod Acartia clausi. Interestingly, genetic sequencing of D1-D2 LSU rDNA revealed that it differs only in one base pair, compared with strains from other regions.


Assuntos
Dinoflagelados/crescimento & desenvolvimento , Dinoflagelados/fisiologia , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/fisiologia , Animais , Contaminação de Alimentos/prevenção & controle , Proliferação Nociva de Algas , Humanos , México/epidemiologia , Oceano Pacífico , Saxitoxina/metabolismo , Saxitoxina/toxicidade , Estações do Ano , Frutos do Mar/análise , Frutos do Mar/microbiologia , Intoxicação por Frutos do Mar/epidemiologia , Intoxicação por Frutos do Mar/prevenção & controle , Especificidade da Espécie , Temperatura
8.
Comp Biochem Physiol C Toxicol Pharmacol ; 149(3): 317-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18786656

RESUMO

The toxic effect of the dinoflagellate Prorocentrum lima on juvenile American whiteleg shrimp Litopenaeus vannamei and giant lion-paw scallop Nodipecten subnodosus was evaluated. Organisms were exposed to three densities (500, 2000, or 5000 cells mL(-1)), superoxide dismutase activity and soluble protein in the hepatopancreas and muscle were determined at 1, 6, 24 and 48 h after challenge. Shrimp exposed at 5000 cells mL(-1) significantly increased SOD activity in the hepatopancreas at 1 h post-challenge, whereas enzymatic activity in muscle significantly increased at 24 h at all densities. Scallops exposed to 500 and 2000 cells mL(-1) showed significant SOD activity increase in hepatopancreas at 24 and 12 h, respectively. Mortality at 48 h was 100% in scallops exposed to 5000 cells mL(-1). Shrimp showed higher levels of SOD activity than scallops. Soluble protein content in the shrimp hepatopancreas was significantly higher at densities of 500 and 2000 cells mL(-1) at 6 and 1 h, respectively. Soluble protein content in the scallop hepatopancreas was higher than control values at 1 h after challenge. In this study, 500 cells mL(-1) was enough to trigger SOD activity in two benthic species exposed to the toxic dinoflagellate P. lima.


Assuntos
Dinoflagelados/patogenicidade , Hepatopâncreas/enzimologia , Músculos/enzimologia , Pectinidae/enzimologia , Penaeidae/enzimologia , Proteínas de Protozoários/metabolismo , Superóxido Dismutase/metabolismo , Animais , Artemia/parasitologia , Bioensaio , Hepatopâncreas/parasitologia , Camundongos , Músculos/parasitologia , Pectinidae/parasitologia , Penaeidae/parasitologia , Fatores de Tempo , Regulação para Cima
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