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1.
Mar Drugs ; 19(8)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34436299

RESUMO

Dinoflagellate species of the genera Gambierdiscus and Fukuyoa are known to produce ciguatera poisoning-associated toxic compounds, such as ciguatoxins, or other toxins, such as maitotoxins. However, many species and strains remain poorly characterized in areas where they were recently identified, such as the western Mediterranean Sea. In previous studies carried out by our research group, a G. australes strain from the Balearic Islands (Mediterranean Sea) presenting MTX-like activity was characterized by LC-MS/MS and LC-HRMS detecting 44-methyl gambierone and gambieric acids C and D. However, MTX1, which is typically found in some G. australes strains from the Pacific Ocean, was not detected. Therefore, this study focuses on the identification of the compound responsible for the MTX-like toxicity in this strain. The G. australes strain was characterized not only using LC-MS instruments but also N2a-guided HPLC fractionation. Following this approach, several toxic compounds were identified in three fractions by LC-MS/MS and HRMS. A novel MTX analogue, named MTX5, was identified in the most toxic fraction, and 44-methyl gambierone and gambieric acids C and D contributed to the toxicity observed in other fractions of this strain. Thus, G. australes from the Mediterranean Sea produces MTX5 instead of MTX1 in contrast to some strains of the same species from the Pacific Ocean. No CTX precursors were detected, reinforcing the complexity of the identification of CTXs precursors in these regions.


Assuntos
Ciguatera , Dinoflagellida/química , Toxinas Marinhas/química , Oxocinas/química , Animais , Organismos Aquáticos , Mar Mediterrâneo , Relação Estrutura-Atividade
2.
Sex Abuse ; 31(8): 930-951, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30047834

RESUMO

The present study investigates whether leuprolide acetate (Lupron) adds to the efficacy of traditional sex offender treatment. A group of sex offenders receiving both Lupron and cognitive behavioral therapy (CBT; n = 25) were compared with a group of sex offenders receiving only CBT (n = 22). Treated subjects were compared with norms available with reference to the Static-99R, as well as compared with a sample of untreated, nonsexual violent offenders (n = 81), to provide baseline data regarding risk of violent recidivism. Results indicated that subjects receiving Lupron were at significantly higher risk of recidivism and significantly more likely to be diagnosed with a paraphilia than subjects receiving only CBT, a priori. Both treated groups of sexual offenders recidivated at substantially lower rates than predicted by the Static-99R. Currently, this study represents the only, long-term outcome study on Lupron administration using officially recorded recidivism as the primary dependent measure.


Assuntos
Terapia Cognitivo-Comportamental , Criminosos , Leuprolida/uso terapêutico , Transtornos Parafílicos/terapia , Reincidência/prevenção & controle , Delitos Sexuais , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Parafílicos/tratamento farmacológico , Transtornos Parafílicos/psicologia
3.
Mar Drugs ; 15(3)2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28335428

RESUMO

Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world. It causes substantial human health, social, and economic impacts. The illness produces a complex array of gastrointestinal, neurological and neuropsychological, and cardiovascular symptoms, which may last days, weeks, or months. This paper is a general review of CFP including the human health effects of exposure to ciguatoxins (CTXs), diagnosis, human pathophysiology of CFP, treatment, detection of CTXs in fish, epidemiology of the illness, global dimensions, prevention, future directions, and recommendations for clinicians and patients. It updates and expands upon the previous review of CFP published by Friedman et al. (2008) and addresses new insights and relevant emerging global themes such as climate and environmental change, international market issues, and socioeconomic impacts of CFP. It also provides a proposed universal case definition for CFP designed to account for the variability in symptom presentation across different geographic regions. Information that is important but unchanged since the previous review has been reiterated. This article is intended for a broad audience, including resource and fishery managers, commercial and recreational fishers, public health officials, medical professionals, and other interested parties.


Assuntos
Ciguatera/epidemiologia , Ciguatoxinas/toxicidade , Peixes/metabolismo , Alimentos Marinhos/intoxicação , Animais , Surtos de Doenças , Humanos , Saúde Pública
4.
Proc Natl Acad Sci U S A ; 109(50): 20274-9, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-22315401

RESUMO

Following the 2010 Deepwater Horizon oil spill, petroleum-related compounds and chemical dispersants were detected in the waters of the Gulf of Mexico. As a result, there was concern about the risk to human health through consumption of contaminated seafood in the region. Federal and Gulf Coast State agencies worked together on a sampling plan and analytical protocols to determine whether seafood was safe to eat and acceptable for sale in the marketplace. Sensory and chemical methods were used to measure polycyclic aromatic hydrocarbons (PAHs) and dispersant in >8,000 seafood specimens collected in federal waters of the Gulf. Overall, individual PAHs and the dispersant component dioctyl sodium sulfosuccinate were found in low concentrations or below the limits of quantitation. When detected, the concentrations were at least two orders of magnitude lower than the level of concern for human health risk. Once an area closed to fishing was free of visibly floating oil and all sensory and chemical results for the seafood species within an area met the criteria for reopening, that area was eligible to be reopened. On April 19, 2011 the area around the wellhead was the last area in federal waters to be reopened nearly 1 y after the spill began. However, as of November 9, 2011, some state waters off the Louisiana coast (Barataria Bay and the Delta region) remain closed to fishing.


Assuntos
Inocuidade dos Alimentos , Poluição por Petróleo/efeitos adversos , Alimentos Marinhos/normas , Animais , Monitoramento Ambiental , Pesqueiros/normas , Humanos , Louisiana , Petróleo/análise , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Alimentos Marinhos/análise , Alimentos Marinhos/toxicidade , Estados Unidos , United States Food and Drug Administration , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/normas , Poluentes Químicos da Água/toxicidade
5.
J AOAC Int ; 97(2): 299-306, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24830140

RESUMO

Ciguatoxins are potent neurotoxins with a significant public health impact. Cytotoxicity assays have allowed the most sensitive means of detection of ciguatoxin-like activity without reliance on mouse bioassays and have been invaluable in studying outbreaks. An improvement of these cell-based assays is presented here in which rapid flow cytometric detection of ciguatoxins and saxitoxins is demonstrated using fluorescent voltage sensitive dyes. A depolarization response can be detected directly due to ciguatoxin alone; however, an approximate 1000-fold increase in sensitivity is observed in the presence of veratridine. These results demonstrate that flow cytometric assessment of ciguatoxins is possible at levels approaching the trace detection limits of our earlier cytotoxicity assays, however, with a significant reduction in analysis time. Preliminary results are also presented for detection of brevetoxins and for automation and throughput improvements to a previously described method for detecting saxitoxins in shellfish extracts.


Assuntos
Ciguatera/metabolismo , Ciguatoxinas/química , Citometria de Fluxo/métodos , Músculo Esquelético/química , Saxitoxina/química , Canais de Sódio/química , Animais , Automação , Linhagem Celular Tumoral , Linguados , Análise de Alimentos , Músculo Esquelético/metabolismo , Neuroblastoma
6.
Arch Sex Behav ; 41(1): 13-29, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20848175

RESUMO

The penile response profiles of homosexual and heterosexual pedophiles, hebephiles, and teleiophiles to laboratory stimuli depicting male and female children and adults may be conceptualized as a series of overlapping stimulus generalization gradients. This study used such profile data to compare two models of alloerotic responding (sexual responding to other people) in men. The first model was based on the notion that men respond to a potential sexual object as a compound stimulus made up of an age component and a gender component. The second model was based on the notion that men respond to a potential sexual object as a gestalt, which they evaluate in terms of global similarity to other potential sexual objects. The analytic strategy was to compare the accuracy of these models in predicting a man's penile response to each of his less arousing (nonpreferred) stimulus categories from his response to his most arousing (preferred) stimulus category. Both models based their predictions on the degree of dissimilarity between the preferred stimulus category and a given nonpreferred stimulus category, but each model used its own measure of dissimilarity. According to the first model ("summation model"), penile response should vary inversely as the sum of stimulus differences on separate dimensions of age and gender. According to the second model ("bipolar model"), penile response should vary inversely as the distance between stimulus categories on a single, bipolar dimension of morphological similarity-a dimension on which children are located near the middle, and adult men and women are located at opposite ends. The subjects were 2,278 male patients referred to a specialty clinic for phallometric assessment of their erotic preferences. Comparisons of goodness of fit to the observed data favored the unidimensional bipolar model.


Assuntos
Literatura Erótica , Homens/psicologia , Modelos Psicológicos , Ereção Peniana/fisiologia , Pênis/irrigação sanguínea , Sexualidade/fisiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Ereção Peniana/psicologia , Sexualidade/psicologia
7.
Sex Abuse ; 22(1): 42-57, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19887688

RESUMO

Phallometric testing is widely considered the best psychophysiological procedure for assessing erotic preferences in men. Researchers have differed, however, on the necessity of setting some minimum criterion of penile response for ascertaining the interpretability of a phallometric test result. Proponents of a minimum criterion have generally based their view on the intuitive notion that "more is better" rather than any formal demonstration of this. The present study was conducted to investigate whether there is any empirical evidence for this intuitive notion, by examining the relation between magnitude of penile response and the agreement in diagnoses obtained in two test sessions using different laboratory stimuli. The results showed that examinees with inconsistent diagnoses responded less on both tests and that examinees with inconsistent diagnoses responded less on the second test after controlling for their response on the first test. Results also indicated that at response levels less than 1 cm(3), diagnostic consistency was no better than chance, supporting the establishment of a minimum response level criterion.


Assuntos
Homens , Pedofilia/diagnóstico , Ereção Peniana , Pletismografia/métodos , Delitos Sexuais/psicologia , Adulto , Recursos Audiovisuais , Psiquiatria Legal/métodos , Humanos , Classificação Internacional de Doenças , Masculino , Homens/psicologia , Pessoa de Meia-Idade , Ontário , Pedofilia/classificação , Pedofilia/psicologia , Ereção Peniana/fisiologia , Ereção Peniana/psicologia , Testes Psicológicos , Psicometria , Reprodutibilidade dos Testes
8.
Sex Abuse ; 22(3): 279-89, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20562410

RESUMO

Phallometric assessments of single-victim sexual offenders against children have suggested that only about 50% of these men are more attracted to children than they are to adults. This has raised the question of what motivates the other 50% of men to approach young girls for sex. Freund et al. showed that gynephilic men (i.e., men preferentially attracted to adult women) evidenced greater arousal to images of prepubescent girls than to images of males of any age or to nonerotic images, arguing that gynephilic men may approach prepubescent girls as a "surrogate" for their preferred erotic targets (i.e., adult women). One might argue that these phallometric results are artifactual, given that they were obtained in a time period during which images of nudity were far less common than they are today (thus any female nudity might have elicited arousal). To address this issue, the authors examined the sexual arousal patterns of 214 contemporary men who, based on self-report, offense history, and phallometric responses, were purely gynephilic. Results showed the "classical control profile": the greatest arousal to adult women, systematically decreasing arousal as the female stimuli became younger, and essentially no arousal to any age categories of males or to neutral (nonerotic) stimuli. Arousal to both pubescent and prepubescent girls was significantly greater than to neutral stimuli (p < .001 for both). Thus, Freund et al.'s results still appear to be valid, and the explanation for child molesting that they suggest still seems to be feasible.


Assuntos
Abuso Sexual na Infância/diagnóstico , Homens , Pedofilia/diagnóstico , Ereção Peniana/fisiologia , Pletismografia/métodos , Adulto , Nível de Alerta/fisiologia , Recursos Audiovisuais , Criança , Abuso Sexual na Infância/classificação , Feminino , Humanos , Masculino , Homens/psicologia , Pessoa de Meia-Idade , Ontário , Pedofilia/classificação , Pênis/fisiologia , Psicometria , Análise de Regressão , Delitos Sexuais , Gravação em Fita , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-31881166

RESUMO

The recent emergence of ciguatera in the eastern Atlantic, particularly in the Canary Islands (Spain) and Madeira (Portugal) prompted the development and implementation of liquid chromatography tandem-mass spectrometry (LC/MS-MS) methods for the detection of ciguatoxins in fish. The complexity of fish tissue matrices, low concentrations of ciguatoxins in hazardous fish, and the scarcity of ciguatoxin standards present challenging issues for successful implementation of routine ciguatoxin analysis. A laboratory reference material of Caribbean Ciguatoxin-1 (C-CTX1), which was previously confirmed in fish responsible for ciguatera outbreaks in the Canary Islands, was used to assess the toxin's stability under strongly acidic conditions and solvent systems commonly used in LC-MS/MS. It was observed that strongly acidic conditions caused the transformation of C-CTX1 to a C56 methoxy congener, C-CTX1-Me. C-CTX1 was structurally characterised by LC-MS/MS and fragmentation pathways are presented showing the same fragmentation pattern as C-CTX1-Me. These results suggest that the use of strongly acidic conditions during sample pretreatment for C-CTX analysis, might produce significant artefacts, and risks failing to detect the presence of C-CTX1.


Assuntos
Ácidos/química , Ciguatoxinas/química , Inocuidade dos Alimentos , Alimentos Marinhos/análise , Animais , Peixes , Concentração de Íons de Hidrogênio
10.
Arch Sex Behav ; 38(3): 335-50, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18686026

RESUMO

The term pedophilia denotes the erotic preference for prepubescent children. The term hebephilia has been proposed to denote the erotic preference for pubescent children (roughly, ages 11 or 12-14), but it has not become widely used. The present study sought to validate the concept of hebephilia by examining the agreement between self-reported sexual interests and objectively recorded penile responses in the laboratory. The participants were 881 men who were referred for clinical assessment because of paraphilic, criminal, or otherwise problematic sexual behavior. Within-group comparisons showed that men who verbally reported maximum sexual attraction to pubescent children had greater penile responses to depictions of pubescent children than to depictions of younger or older persons. Between-groups comparisons showed that penile responding distinguished such men from those who reported maximum attraction to prepubescent children and from those who reported maximum attraction to fully grown persons. These results indicated that hebephilia exists as a discriminable erotic age-preference. The authors recommend various ways in which the DSM might be altered to accommodate the present findings. One possibility would be to replace the diagnosis of Pedophilia with Pedohebephilia and allow the clinician to specify one of three subtypes: Sexually Attracted to Children Younger than 11 (Pedophilic Type), Sexually Attracted to Children Age 11-14 (Hebephilic Type), or Sexually Attracted to Both (Pedohebephilic Type). We further recommend that the DSM-V encourage users to record the typical age of children who most attract the patient sexually as well as the gender of children who most attract the patient sexually.


Assuntos
Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos Mentais/classificação , Pedofilia/classificação , Adulto , Humanos , Modelos Lineares , Masculino , Ereção Peniana/psicologia , Pênis/fisiologia , Puberdade , Autoavaliação (Psicologia) , Delitos Sexuais/psicologia , Comportamento Sexual/fisiologia , Comportamento Sexual/psicologia
11.
Sex Abuse ; 21(4): 431-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19901237

RESUMO

There are at least two different criteria for assessing pedophilia in men: absolute ascertainment (their sexual interest in children is intense) and relative ascertainment (their sexual interest in children is greater than their interest in adults). The American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, 3rd edition (DSM-III) used relative ascertainment in its diagnostic criteria for pedophilia; this was abandoned and replaced by absolute ascertainment in the DSM-III-R and all subsequent editions. The present study was conducted to demonstrate the continuing need for relative ascertainment, particularly in the laboratory assessment of pedophilia. A total of 402 heterosexual men were selected from a database of patients referred to a specialty clinic. These had undergone phallometric testing, a psychophysiological procedure in which their penile blood volume was monitored while they were presented with a standardized set of laboratory stimuli depicting male and female children, pubescents, and adults.The 130 men selected for the Teleiophilic Profile group responded substantially to prepubescent girls but even more to adult women; the 272 men selected for the Pedophilic Profile group responded weakly to prepubescent girls but even less to adult women. In terms of absolute magnitude, every patient in the Pedophilic Profile group had a lesser penile response to prepubescent girls than every patient in the Teleiophilic Profile group. Nevertheless, the Pedophilic Profile group had a significantly greater number of known sexual offenses against prepubescent girls, indicating that they contained a higher proportion of true pedophiles. These results dramatically demonstrate the utility-or perhaps necessity-of relative ascertainment in the laboratory assessment of erotic age-preference.


Assuntos
Homens , Pedofilia/diagnóstico , Ereção Peniana , Pletismografia/métodos , Psicofisiologia/métodos , Adolescente , Adulto , Recursos Audiovisuais , Criança , Comportamento de Escolha , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Psiquiatria Legal/métodos , Humanos , Masculino , Homens/psicologia , Ontário , Pedofilia/classificação , Pedofilia/fisiopatologia , Pedofilia/psicologia , Ereção Peniana/fisiologia , Ereção Peniana/psicologia , Pletismografia/normas , Testes Psicológicos , Psicometria , Psicofisiologia/normas , Encaminhamento e Consulta , Gravação em Fita
12.
Food Chem ; 280: 8-14, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30642510

RESUMO

The increased emergence of Ciguatera Fish Poisoning in the Canary Islands and Madeira demanded the development of confirmatory methods by liquid chromatography coupled to tandem mass spectrometry to characterize the risk. Efforts were particularly focused on the optimization of sample pretreatment, especially in the sample cleanup step, to efficiently remove matrix interferences as a critical factor to consider in mass spectrometry detection. Two different LC-MS/MS approaches have been used for confirmation purposes, the first one using the sodium adduct as precursor and product ion to allow an increased sensitivity in the detection, whereas additional fragments were also monitored for further confirmation. The optimized conditions above mentioned allowed the confirmation of Caribbean Ciguatoxin-1 as the main responsible for the samples analyzed from these geographical areas, while the presence of a new hydroxyl metabolite of C-CTX1 was also confirmed in one sample analyzed in this study.


Assuntos
Ciguatoxinas/análise , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Ciguatera , Ciguatoxinas/isolamento & purificação , Peixes/metabolismo , Limite de Detecção , Alimentos Marinhos/análise , Extração em Fase Sólida , Espanha
13.
Toxicon ; 164: 44-50, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30954452

RESUMO

Compounds similar to maitotoxin (MTX) have been isolated from several laboratory strains of the dinoflagellate Gambierdiscus spp. from the Caribbean. Mass spectral results suggest that these compounds differ from MTX by the loss of one sulfate group and, in some cases, the loss of one methyl group with the addition of one degree of unsaturation. NMR experiments, using approximately 50 nmol of one of these compounds, have demonstrated that the 9-sulfo group of MTX is still present, suggesting that these compounds are 40-desulfo congeners of MTX.


Assuntos
Dinoflagellida/química , Toxinas Marinhas/química , Oxocinas/química , Região do Caribe , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
14.
J Psychiatr Res ; 42(3): 167-83, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18039544

RESUMO

The present investigation sought to identify which brain regions distinguish pedophilic from nonpedophilic men, using unbiased, automated analyses of the whole brain. T1-weighted magnetic resonance images (MRIs) were acquired from men who demonstrated illegal or clinically significant sexual behaviors or interests (n = 65) and from men who had histories of nonsexual offenses but no sexual offenses (n = 62). Sexual interest in children was assessed by participants' admissions of pedophilic interest, histories of committing sexual offenses against children, and psychophysiological responses in the laboratory to erotic stimuli depicting children or adults. Automated parcellation of the MRIs revealed significant negative associations between pedophilia and white matter volumes of the temporal and parietal lobes bilaterally. Voxel-based morphometry corroborated the associations and indicated that the regions of lower white matter volumes followed, and were limited to, two major fiber bundles: the superior fronto-occipital fasciculus and the right arcuate fasciculus. No significant differences were found in grey matter or in cerebrospinal fluid (CSF). Because the superior fronto-occipital and arcuate fasciculi connect the cortical regions that respond to sexual cues, these results suggest (1) that those cortical regions operate as a network for recognizing sexually relevant stimuli and (2) that pedophilia results from a partial disconnection within that network.


Assuntos
Núcleo Arqueado do Hipotálamo/fisiopatologia , Pedofilia/fisiopatologia , Adolescente , Antropometria , Criança , Abuso Sexual na Infância/psicologia , Abuso Sexual na Infância/estatística & dados numéricos , Literatura Erótica , Lobo Frontal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Parietal/fisiopatologia , Pedofilia/líquido cefalorraquidiano , Pedofilia/epidemiologia , Pênis/anatomia & histologia , Comportamento Sexual/psicologia , Lobo Temporal/fisiopatologia
15.
Toxicon ; 52(2): 237-45, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18582487

RESUMO

Urine specimens from patients diagnosed with neurotoxic shellfish poisoning (NSP) were examined for biomarkers of brevetoxin intoxication. Brevetoxins were concentrated from urine by using solid-phase extraction (SPE), and analyzed by enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine extracts were fractionated by LC, and fractions analyzed for brevetoxins by ELISA. In subsequent LC-MS/MS analyses, several brevetoxin metabolites of B-type backbone were identified, with elution profiles consistent with those of ELISA. The more abundant brevetoxin metabolites in urine were characterized structurally by LC-MS/MS. With the exception of BTX-3, brevetoxin metabolites in urine differed from those found in shellfish and in shellfish meal remnants. Proposed structures of these major urinary metabolites are methylsulfoxy BTX-3, 27-epoxy BTX-3, and reduced BTX-B5. BTX-3 was found in all specimens examined. BTX-3 concentrations in urine, as determined by LC-MS/MS, correlated well with composite toxin measurements by ELISA (r(2)=0.96). BTX-3 is a useful biomarker for confirmation of clinical diagnosis of NSP.


Assuntos
Bivalves/metabolismo , Dinoflagellida , Doenças Transmitidas por Alimentos , Toxinas Marinhas/intoxicação , Neurotoxinas/intoxicação , Oxocinas/intoxicação , Intoxicação por Frutos do Mar , Animais , Biomarcadores/química , Biomarcadores/urina , Ensaio de Imunoadsorção Enzimática , Toxinas Marinhas/química , Toxinas Marinhas/urina , Estrutura Molecular , Neurotoxinas/química , Neurotoxinas/urina , Oxocinas/química , Oxocinas/urina , Frutos do Mar/análise
16.
Toxicon ; 52(1): 32-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18582486

RESUMO

Brevetoxin uptake and elimination were examined in Eastern oyster (Crassostrea virginica) exposed to recurring blooms of the marine alga Karenia brevis in Sarasota Bay, FL, over a three-year period. Brevetoxins were monitored by in vitro assays (ELISA, cytotoxicity assay, and receptor binding assay) and LC-MS, with in vivo toxicity of shellfish extracts assessed by the traditional mouse bioassay. Measurements by all methods reflected well the progression and magnitude of the blooms. Highest levels recorded by mouse bioassay at bloom peak were 157 MU/100g. Oysters were toxic by mouse bioassay at levels >or=20 MU/100g for up to two weeks after bloom dissipation, whereas brevetoxins were measurable by in vitro assays and LC-MS for several months afterwards. For the structure-based methods, summed values for the principal brevetoxin metabolites of PbTx-2 (cysteine and cysteine sulfoxide conjugates), as determined by LC-MS, were highly correlated (r(2)=0.90) with composite toxin measurements by ELISA. ELISA and LC-MS values also correlated well (r(2)=0.74 and 0.73, respectively) with those of mouse bioassay. Pharmacology-based cytotoxicity and receptor binding assays did not correlate as well (r(2)=0.65), and were weakly correlated with mouse bioassay (r(2)=0.48 and 0.50, respectively). ELISA and LC-MS methods offer rapid screening and confirmation, respectively, of brevetoxin contamination in the oyster, and are excellent alternatives to mouse bioassay for assessing oyster toxicity following K. brevis blooms.


Assuntos
Crassostrea/metabolismo , Dinoflagellida/patogenicidade , Monitoramento Ambiental , Toxinas Marinhas/análise , Oxocinas/análise , Animais , Bioensaio , Cromatografia Líquida , Contaminação de Alimentos , Toxinas Marinhas/toxicidade , Espectrometria de Massas , Camundongos , Oxocinas/toxicidade
17.
Mar Drugs ; 6(3): 456-79, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19005579

RESUMO

Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world, and it causes substantial physical and functional impact. It produces a myriad of gastrointestinal, neurologic and/or cardiovascular symptoms which last days to weeks, or even months. Although there are reports of symptom amelioration with some interventions (e.g. IV mannitol), the appropriate treatment for CFP remains unclear to many physicians. We review the literature on the treatments for CFP, including randomized controlled studies and anecdotal reports. The article is intended to clarify treatment options, and provide information about management and prevention of CFP, for emergency room physicians, poison control information providers, other health care providers, and patients.


Assuntos
Ciguatera/prevenção & controle , Ciguatera/terapia , Ciguatera/diagnóstico , Ciguatoxinas , Humanos
18.
J AOAC Int ; 90(1): 173-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17373449

RESUMO

A new competitive electrochemiluminescence-based immunoassay for the type-2 brevetoxins in oyster extracts was developed. The assay was verified by spiking known amounts of PbTx-3 into 80% methanol extracts of Gulf Coast oysters. We also provide preliminary data demonstrating that 100% acetone extracts, aqueous homogenates, and the clinical matrixes urine and serum can also be analyzed without significant matrix interferences. The assay offers the advantages of speed ( 2 h analysis time); simplicity (only 2 additions, one incubation period, and no wash steps before analysis); low limit of quantitation (conservatively, 50 pg/mL = 1 ng/g tissue equivalents); and a stable, nonradioactive label. Due to the variety of brevetoxin metabolites present and the lack of certified reference standards for liquid chromatography-mass spectrometry confirmation, a true validation of brevetoxins in shellfish extracts is not possible at this time. However, our assay correlated well with another brevetoxin immunoassay currently in use in the United States. We believe this assay could be useful as a regulatory screening tool and could support pharmacokinetic studies in animals and clinical evaluation of neurotoxic shellfish poisoning victims.


Assuntos
Toxinas Marinhas/química , Neurotoxinas/química , Ostreidae/química , Oxocinas/química , Extratos de Tecidos/análise , Animais , Eletroquímica/métodos , Humanos , Imunoensaio/métodos , Luminescência , Toxinas Marinhas/sangue , Toxinas Marinhas/isolamento & purificação , Toxinas Marinhas/urina , Modelos Moleculares , Estrutura Molecular , Neurotoxinas/isolamento & purificação , Oxocinas/sangue , Oxocinas/isolamento & purificação , Oxocinas/urina , Reprodutibilidade dos Testes , Rutênio
19.
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
Dinoflagellida/química , Intoxicação/epidemiologia , Saxitoxina/intoxicação , Takifugu , Animais , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Humanos , Toxinas Marinhas/intoxicação , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Estados Unidos/epidemiologia
20.
Toxicon ; 48(1): 104-15, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16808941

RESUMO

Several novel brevetoxin derivatives were isolated and identified in Karenia brevis cultures and natural blooms by using solid phase extraction (SPE) and LC/MS(MS) techniques. These analogs were more polar compared with previously described brevetoxins, and were poorly extractable by conventional non-polar solvent (chloroform) partitioning. Brevetoxin analogs were structurally confirmed as hydrolyzed (open A-ring) forms of brevetoxins PbTx-1, PbTx-7, PbTx-2, and PbTx-3, and of oxidized PbTx-1 and PbTx-2. Some of these open A-ring derivatives were in greater abundance than their non-hydrolyzed counterparts. All were in much greater abundance in bloom water filtrate compared with cell-rich fractions. Open A-ring compounds were cytotoxic in mouse neuroblastoma (N2a) cell assay. In the K. brevis bloom-exposed Eastern oyster, brevetoxin metabolites with opened A rings were identified (e.g., open-ring cysteine-PbTx conjugates), contributing to their overall toxin burden.


Assuntos
Dinoflagellida/patogenicidade , Toxinas Marinhas/toxicidade , Oxocinas/toxicidade , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Crassostrea/metabolismo , Toxinas Marinhas/química , Toxinas Marinhas/isolamento & purificação , Espectrometria de Massas , Camundongos , Neuroblastoma/patologia , Oxocinas/química , Oxocinas/isolamento & purificação
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