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1.
Toxins (Basel) ; 13(11)2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34822554

RESUMO

Fumonisins (FB) are mycotoxins known to exert most of their toxicity by blocking ceramide synthase, resulting in disruption of sphingolipid metabolism. Although the effects of FB on sphinganine (Sa) and sphingosine (So) are well documented in poultry, little information is available on their other effects on sphingolipids. The objective of this study was to analyze the effects of FB on the hepatic and plasma sphingolipidome in chickens. The first concern of this analysis was to clarify the effects of FB on hepatic sphingolipid levels, whose variations can lead to numerous toxic manifestations. The second was to specify the possible use of an alteration of the sphingolipidome as a biomarker of exposure to FB, in addition to the measurement of the Sa:So ratio already widely used. For this purpose, we developed an UHPLC MS/MS method that enabled the determination of 82 SL, including 10 internal standards, in chicken liver and plasma. The validated method was used to measure the effects of FB administered to chickens at a dose close to 20 mg FB1 + FB2/kg feed for 9 days. Significant alterations of sphingoid bases, ceramides, dihydroceramides, glycosylceramides, sphingomyelins and dihydrosphingomyelins were observed in the liver. In addition, significant increases in plasma sphinganine 1-phosphate, sphingosine 1-phosphate and sphingomyelins were observed in plasma. Interestingly, partial least-squares discriminant analysis of 11 SL in plasma made it possible to discriminate exposed chickens from control chickens, whereas analysis of Sa and So alone revealed no difference. In conclusion, our results show that the effects of FB in chickens are complex, and that SL profiling enables the detection of exposure to FB when Sa and So fail.


Assuntos
Galinhas/metabolismo , Fumonisinas/administração & dosagem , Venenos/administração & dosagem , Esfingolipídeos/metabolismo , Animais , Relação Dose-Resposta a Droga , Lipidômica
2.
Pan Afr Med J ; 38: 42, 2021.
Artigo em Francês | MEDLINE | ID: mdl-33854671

RESUMO

INTRODUCTION: intentional poisoning is a major public health problem in both developed and developing countries. The purpose of this study is to describe the epidemiological features of criminal intoxication in Morocco. METHOD: we conducted a retrospective study of all cases of criminal intoxication identified by the Morocco Poison Control and Pharmacovigilance Centre (MPCPC) between 1980 and 2014. RESULTS: during the study period, 611 cases of criminal poisoning were recorded, reflecting a rate of 2.1% of all intentional poisoning reported during the same period. The average age of intoxicated patients was 26.4±14.3 years. More than a quarter of the subjects were children under the age of 15 (28.6%). According to the study results, 55.9% were male, with a sex-ratio (M/F) of 1.3. The majority of cases (89.4%) occurred in urban areas. Collective intoxications were reported in 24.4% of cases. The most frequently used products were pesticides (19.1%) and plants (19%). Patients developed different symptoms based on the toxic substances used, the amount ingested and the time elapsed before treatment. A range of digestive, neurological, respiratory and cardiovascular disorders were reported. Out of 440 patients with outcome data available, 27 died. The remainder of patients survived with or without sequelae. CONCLUSION: criminal poisoning is a major issue. The number of cases is probably underestimated due to a large number of undiagnosed or unreported cases.


Assuntos
Crime , Farmacovigilância , Intoxicação/epidemiologia , Venenos/administração & dosagem , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Marrocos/epidemiologia , Praguicidas/envenenamento , Intoxicação por Plantas/epidemiologia , Centros de Controle de Intoxicações/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
3.
J. venom. anim. toxins incl. trop. dis ; 27: e20200179, 2021. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1279402

RESUMO

Neutrophils play a pivotal role in innate immunity and in the inflammatory response. Neutrophils are very motile cells that are rapidly recruited to the inflammatory site as the body first line of defense. Their bactericidal activity is due to the release into the phagocytic vacuole, called phagosome, of several toxic molecules directed against microbes. Neutrophil stimulation induces release of this arsenal into the phagosome and induces the assembly at the membrane of subunits of the NAPDH oxidase, the enzyme responsible for the production of superoxide anion that gives rise to other reactive oxygen species (ROS), a process called respiratory burst. Altogether, they are responsible for the bactericidal activity of the neutrophils. Excessive activation of neutrophils can lead to extensive release of these toxic agents, inducing tissue injury and the inflammatory reaction. Envenomation, caused by different animal species (bees, wasps, scorpions, snakes etc.), is well known to induce a local and acute inflammatory reaction, characterized by recruitment and activation of leukocytes and the release of several inflammatory mediators, including prostaglandins and cytokines. Venoms contain several molecules such as enzymes (phospholipase A2, L-amino acid oxidase and proteases, among others) and peptides (disintegrins, mastoporan, parabutoporin etc.). These molecules are able to stimulate or inhibit ROS production by neutrophils. The present review article gives a general overview of the main neutrophil functions focusing on ROS production and summarizes how venoms and venom molecules can affect this function.(AU)


Assuntos
Animais , Venenos/administração & dosagem , Espécies Reativas de Oxigênio , NADPH Oxidases , L-Aminoácido Oxidase , Neutrófilos , Anti-Inflamatórios
4.
J Anim Physiol Anim Nutr (Berl) ; 104(5): 1531-1539, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32166807

RESUMO

The purpose of the present study was to evaluate the short-term effects of aflatoxin B1 (AFB1 ) and deoxynivalenol (DON) exposure on the expression of the genes encoding the glutathione redox system glutathione peroxidase 4a (gpx4a), glutathione peroxidase 4b (gpx4b), glutathione synthetase (gss) and glutathione reductase (gsr) and the oxidative stress response-related transcription factors Kelch-like ECH-associated protein 1 (keap1) and nuclear factor-erythroid 2 p45-related factor 2 (nrf2) in liver, kidney and spleen of common carp. During the 24-hr long experiment, three different doses (5 µg AFB1 and 110 µg DON; 7.5 µg AFB1 and 165 µg DON or 10 µg AFB1 and 220 µg DON/kg bw) were used. The results indicated that the co-exposure of AFB1 and DON initiated free radical formation in liver, kidney and spleen, which was suggested by the increase in Nrf2 dependent genes, namely gpx4a, gpx4b, gss and gsr. Expression of keap1 gene showed upregulation after 8 hr of mycotoxin exposure, and also upregulation of nrf2 gene was found in kidney after 8 hr of exposure, while in the liver, only slight differences were observed. The changes in the expression of the analysed genes suggest that level of reactive oxygen species reached a critical level where other signalling pathway was activated as described by the hierarchical model of oxidative stress.


Assuntos
Aflatoxina B1/toxicidade , Carpas , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Tricotecenos/toxicidade , Aflatoxina B1/administração & dosagem , Animais , Oxirredução , Venenos/administração & dosagem , Venenos/toxicidade , Tricotecenos/administração & dosagem
5.
Best Pract Res Clin Anaesthesiol ; 33(1): 3-21, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31272651

RESUMO

Regional anesthesia has been advocated as adjunct to a multimodal analgesia regimen. The limited duration of the action of available local anesthetics limits their application. Catheters, perineural or IV adjuvants, or repetition of blocks are modalities available to prolong the analgesic benefit of LRA. All of these approaches have their shortcomings. New extended release local anesthetic formulations may provide time-efficient and longer duration of analgesia with a single injection. Available data on liposomal bupivacaine are promising, and more recently, it has been FDA approved for use in interscalene brachial plexus block but not for other nerve blocks at this time. Several other new formulations and compounds, such as HTX-011, Neosaxitoxin, and SABER-Bupivacaine, are also being developed and tested for their safety and analgesic potential.


Assuntos
Anestésicos Locais/administração & dosagem , Bloqueio Nervoso/métodos , Manejo da Dor/métodos , Dor Pós-Operatória/tratamento farmacológico , Venenos/administração & dosagem , Anestésicos Locais/farmacocinética , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Humanos , Bloqueio Nervoso/tendências , Manejo da Dor/tendências , Dor Pós-Operatória/metabolismo , Venenos/farmacocinética
6.
Campinas; s.n; 2019. ilus, graf, tab.
Tese em Português | LILACS | ID: biblio-1118162

RESUMO

Resumo: O veneno da aranha Phoneutria nigriventer (PNV) contém neuropeptídeos que afetam canais iônicos e a neurotransmissão, induzindo a quebra da barreira hematoencefálica (BHE) no hipocampo de ratos, o que ocorre paralelamente ao aumento do fator de crescimento endotelial vascular (VEGF). Sabe-se que a resposta biológica do VEGF é desencadeada através da regulação transcricional promovida pelo domínio tirosina-quinase de receptores transmembranares do VEGF, dos quais o VEGFR-2 (Flk-1) é considerado o principal mediador e ativador de várias vias de sinalização. O trabalho propõe investigar o possível papel neuroprotetor do VEGF após inibir sua ligação ao receptor Flk-1 pelo itraconazol (ITZ). Para isso, examinamos o status bioquímico do hipocampo por espectroscopia no Infravermelho com Transformada de Fourier (FT-IR), bem como avaliamos as proteínas envolvidas nas rotas paracelular e transcelular da BHE e quais vias de sinalização, relacionadas à neuroproteção do VEGF, foram ativadas. Os ratos receberam PNV ou foram pré-tratados com ITZ (30 min) seguido de PNV pela veia da cauda e depois sacrificados em 1 e 2 h (intervalos com maiores sinais de intoxicação), 5 h (intervalo com sinais incipientes de recuperação) e 24 h (intervalo sem sinal visual detectável de envenenamento), sendo comparados aos controles, salina e ITZ. O pré-tratamento com o antifúngico agravou os efeitos do veneno e aumentou danos à BHE. Os espectros FT-IR do veneno, hipocampo dos controles, PNV e ITZ-PNV mostraram as bandas de 1400 cm-1 (carboxilato) e de 1467 cm-1 (flexão de CH2: principalmente lipídios), que foram considerados bandas biomarcadora e referência, respectivamente. A inibição da ligação VEGF/Flk-1 produziu mudanças marcantes na estabilidade lipídios/proteínas em 1-2 h. As maiores diferenças ocorreram nas regiões espectrais atribuídas à lípides simétricos (2852 cm-1) e assimétricos (2924 e 2968 cm-1). As análises quantitativas mostraram maiores aumentos na razão 1400 cm-1/1467 cm-1 no período de intoxicação grave (1 h), e referem-se à região espectral de 3106 cm-1 a 687 cm-1. Ademais, a desativação da ligação VEGF/Flk-1 pelo itraconazol (ITZ) aumentou o fator indutor de hipóxia (H1F1-?), VEGF, Flk-1, Flt-1, Neu-N e caspase-3 às 5 horas após a injeção do PNV. No mesmo intervalo, a permeabilidade transcelular da BHE aumentou (caveolina-1?, dinamina-2 e família Src de não receptores tirosina-quinase (SKFs)), enquanto laminina e a via paracelular (occludina, ?-catenina) foram reforçadas e a proteína de efluxo glicoproteína-P (P-gp) aumentou. Ao mesmo tempo (5 h), ocorreu auto-fosforilação da via pró-proliferação celular (p38-fosforilada). Às 24 h, apesar da ausência de sinais de intoxicação, a via pró-sobrevivência celular (Akt-fosforilada) diminuiu nos animais pré-tratados com ITZ, enquanto aumentou nos tratados com PNV apenas. Os dados indicam ativação de mecanismos de neuroproteção relacionados ao VEGF envolvendo o receptor Flk-1 e principalmente à serina-treonina-quinase Akt, provavelmente via PI3K. ERK-fosforilada (2 h) e p38-fosforilada (5 h) sugerem interação entre as vias de sinalização com o objetivo de restabelecer a homeostase do hipocampo. O intervalo de 5 h parece ser o ponto de virada orquestrando respostas biológicas variadas. Os dados permitem concluir sobre o papel neuroprotetor do VEGF e que o mesmo pode ser explorado como possível alvo terapêutico no envenenamento por P. nigriventer.(AU)


Abstract: Phoneutria nigriventer spider venom (PNV) contains ion channels-acting neuropeptides that affect neurotransmission and induces transitory blood-brain barrier (BBB) breakdown in rat¿s hippocampus, which run in parallel with (vascular endothelial growth factor) VEGF upregulation. It is known that VEGF biological response is triggered through transcriptional regulation promoted by transmembrane tyrosine kinase receptors, being VEGFR-2 (Flk-1) considered the major mediator of VEGF effect through activation of a number of signaling pathways. The purpose of this work is to investigate a putative neuroprotective role of VEGF by inhibiting its binding to receptor Flk-1 by itraconazole (ITZ). To do this, we examined the biochemical status of the hippocampus by Infrared Spectroscopy and Fourier Transform (FT-IR), as well as evaluated the proteins involved in the BBB paracellular and transcellular routes and which signaling pathways related to VEGF neuroprotection were activated. Rats were administered PNV alone or were pre-treated with ITZ (30 min) followed by PNV through the tail vein, and then euthanized at 1 and 2 h (intervals with greatest signs of intoxication), 5 h (interval with incipient signs of animals¿ recovery) and 24 h (interval with no visually detectable envenomation sign) and compared to saline and ITZ controls. The antifungal pre-treatment aggravated PNV toxic effects and increased BBB damage. FT-IR spectra of venom and from hippocampi of controls, PNV and ITZ-PNV showed a 1400 cm-1 band linked to symmetric stretch of carboxylate and 1467 cm-1 band (CH2 bending: mainly lipids), which were considered biomarker and reference bands, respectively. Inhibition of VEGF/Flk-1 binding produced marked changes in lipid/protein stability at 1-2 h. The largest differences were observed in spectra regions assigned to lipids, both symmetric (2852 cm-1) and asymmetric (2924 and 2968 cm-1). Quantitative analyses showed greatest increases in the 1400 cm-1/1467 cm-1 ratio also at 1 h. Such changes at period of rats¿ severe intoxication referred to wavenumber region from 3106 cm-1 to 687 cm-1. Furthermore, the deactivation of Flk-1 receptor by VEGF through itraconazole (ITZ) showed increased hypoxia inducible factor (H1F-1?), VEGF, Flk-1, Flt-1, Neu-N and caspase-3 at 5 h after PNV injection. At same interval, BBB transcellular permeability increased (caveolin-1?, dynamin-2 and Src family of non-receptor tyrosine kinases (SKFs)), while laminin and paracellular route (occludin, ?-catenin) were reinforced and P-glycoprotein (P-gp) efflux protein was increased. Such effects were timely followed by upregulation of auto-phosphorylation of the pro-proliferation (phosphorylated-p38) pathway. At 24 h, despite absence of intoxication signs, the pro-survival (p-Akt) pathway was downregulated in animals underwent inhibition of VEGF-Flk-1 binding, whereas it was upregulated in PNV rats non-treated with ITZ. The data indicate triggering of VEGF-related mechanisms involving Flk-1 receptor and serine-threonine kinase Akt, probably via PI3K, as the main mechanism of neuroprotection. Phosphorylated ERK (2 h) and p-p38 (5 h) indicates interplay among transduction pathways likely aiming at re-establishment of hippocampal homeostasis. The findings suggest 5 h interval as the turning point that orchestrates varied biological responses. Taking together the data of the present study allow concluding that VEGF expression exerts neuroprotective role and can be explored as a possible therapeutic target in P. nigriventer envenomation.(AU)


Assuntos
Ratos , Venenos de Aranha , Barreira Hematoencefálica , Fator A de Crescimento do Endotélio Vascular , Intoxicação , Venenos/administração & dosagem , Sistema Nervoso Central , Itraconazol , Neuroproteção , Canais Iônicos
7.
BMJ Open ; 8(8): e021881, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158226

RESUMO

OBJECTIVES: Up-to-date information on the patterns of acute poisoning is crucial for the proper management of poisoning events. The objectives of this study were to analyse the characteristics of patients suffering from acute poisoning admitted to the emergency department (ED) in a tertiary medical centre in Northeast China and to compare these characteristics with those of a previous comparable study. DESIGN: Retrospective and descriptive study. SETTING: Data were collected from the hospital information system in Shengjing Hospital, China, from January 2012 to December 2016. PARTICIPANTS: All cases aged ≥11 years old with a diagnosis of acute poisoning. RESULTS: In total, 5009 patients aged ≥11 years presented to the ED with acute poisoning during the study period. The average age of the patients was 36.0±15.1 years and over half (52.7%) were in the 20-39age group. The female to male ratio was 1.2:1. Patients with acute poisoning mainly lived in rural areas rather than in urban areas. The majority of patients consumed poison as suicide attempts (56.7%). Men were more commonly poisoned by drug abuse than women, but women outnumbered men in suicidal poisoning. The most common form of poison intake was ingestion (oral intake; 86.2%). The five most common toxic agent groups, in descending order, were therapeutic drugs (32.6%), pesticides (26.9%), alcohol (20.7%), fumes/gases/vapours (11.4%) and chemicals (3.6%). Sedatives/hypnotics in the therapeutic drugs group and paraquat in the pesticides group were the most common toxic agents, respectively. The mortality rate of study participants was 1.3%, with 64 deaths. CONCLUSIONS: The results of this study indicate the need to strengthen education on the rational and safe use of drugs in Shenyang.


Assuntos
Acidentes/estatística & dados numéricos , Overdose de Drogas/epidemiologia , Serviço Hospitalar de Emergência , Praguicidas/envenenamento , Intoxicação/epidemiologia , Venenos/administração & dosagem , Tentativa de Suicídio/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , China/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Exposição Ambiental , Etanol/envenenamento , Feminino , Doenças Transmitidas por Alimentos , Gases/efeitos adversos , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação/mortalidade , Venenos/efeitos adversos , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias , Centros de Atenção Terciária , Adulto Jovem
8.
Microb Pathog ; 124: 82-88, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30138754

RESUMO

It has been recognized that oxidative stress is implicated in the initiation and progression of diseases due to the excessive formation of free radicals and impairment of the antioxidant defense system, contributing to the mortality of affected animals. The occurrence of a disequilibrium between the antioxidant/oxidant status in serum and liver of freshwater fish fed with aflatoxin B1 (AFB1) remains poorly understood and limited to only a few oxidant variables. Thus, the aim of this study was to evaluate whether an AFB1-contaminated diet causes disturbance on the antioxidant and oxidant status in silver catfish (Rhamdia quelen) of freshwater. Serum and hepatic reactive oxygen species (ROS), metabolites of nitric oxide (NOx), and lipid hydroperoxide increased on days 14 and 21 post-feeding in animals that received AFB1 contaminated diet compared to the control group (basal diet), while protein carbonylation levels increased on day 21 post-feeding. On the other hand, serum and hepatic antioxidant capacity against peroxyl radical and vitamin C levels, as well as glutathione peroxidase and catalase activities were lower on days 14 and 21 post-feeding in animals that received AFB1 contaminated diet compared to the control group. No difference was observed between groups regarding the superoxide dismutase activity and glutathione levels. Based on these evidences, an AFB1-contaminated diet causes a disturbance on serum and hepatic antioxidant/oxidant system due to lipid and protein damage elicited by excessive ROS and NOx production. Also, the antioxidant defense system was unable to avoid or minimize ROS and NOx deleterious effects, and consequently, the oxidative damage. In summary, this disturbance can contribute to understand the pathophysiology and mortality of fish after the consumption of AFB1-contaminated diets.


Assuntos
Aflatoxina B1/toxicidade , Peixes-Gato , Doenças dos Peixes/patologia , Fígado/patologia , Intoxicação/veterinária , Venenos/toxicidade , Soro/química , Administração Oral , Aflatoxina B1/administração & dosagem , Experimentação Animal , Animais , Antioxidantes/análise , Peróxidos Lipídicos/análise , Fígado/efeitos dos fármacos , Óxido Nítrico/análise , Estresse Oxidativo , Intoxicação/patologia , Venenos/administração & dosagem , Carbonilação Proteica , Espécies Reativas de Oxigênio/análise , Fatores de Tempo
9.
Cancer Prev Res (Phila) ; 11(2): 103-112, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29089331

RESUMO

We aimed to determine whether aflatoxin dietary exposure plays a role in the high incidence of hepatocellular carcinoma (HCC) observed among Hispanics in South Texas. We measured TP53R249S somatic mutation, hallmark of aflatoxin etiology in HCC, using droplet digital PCR and RFLP. TP53R249S mutation was detected in 3 of 41 HCC tumors from Hispanics in South Texas (7.3%). We also measured TP53R249S mutation in plasma cell-free DNA (cfDNA) from 218 HCC patients and 96 Hispanic subjects with advanced fibrosis or cirrhosis, from South Texas. The mutation was detected only in Hispanic and Asian HCC patients, and patients harboring TP53R249S mutation were significantly younger and had a shorter overall survival. The mutation was not detected in any Hispanic subject with advanced fibrosis or cirrhosis. Genes involved in cell-cycle control of chromosomal replication and in BRCA1-dependent DNA damage response were enriched in HCCs with TP53R249S mutation. The E2F1 family members, E2F1 and E2F4, were identified as upstream regulators. TP53R249S mutation was detected in 5.7% to 7.3% of Hispanics with HCC in South Texas. This mutation was associated with a younger age and worse prognosis. TP53R249S was however not detected in Hispanics in South Texas with cirrhosis or advanced fibrosis. Aflatoxin exposure may contribute to a small number of HCCs in Hispanics in South Texas, but the detection of TP53R249S mutation in plasma cfDNA is not a promising biomarker of risk assessment for HCC in subjects with cirrhosis or advanced fibrosis in this population. Cancer Prev Res; 11(2); 103-12. ©2017 AACR.


Assuntos
Aflatoxinas/administração & dosagem , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hispânico ou Latino/genética , Neoplasias Hepáticas/genética , Mutação , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Ácidos Nucleicos Livres , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Venenos/administração & dosagem , Prevalência , Prognóstico , Texas/epidemiologia
10.
West J Emerg Med ; 18(5): 923-927, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28874945

RESUMO

INTRODUCTION: Topical benzocaine is a local anesthetic commonly used to relieve pain caused by teething, periodontal irritation, burns, wounds, and insect bites. Oral preparations may contain benzocaine concentrations ranging from 7.5% to 20%. Pediatric exposure to such large concentrations may result in methemoglobinemia and secondarily cause anemia, cyanosis, and hypoxia. METHODS: This is a retrospective study of exposures reported to a statewide poison control system. The electronic health records were queried for pediatric exposures to topical benzocaine treated at a healthcare facility from 2004 to 2014. Cases of benzocaine exposure were reviewed for demographic and clinical information, and descriptive statistical analysis was performed. RESULTS: The query resulted in 157 cases; 58 were excluded due to co-ingestants, or miscoding of non-benzocaine exposures. Children four years of age and younger represented the majority of cases (93%) with a median age of 1 year. There were 88 cases of accidental/ exploratory exposure, while 6 cases resulted from therapeutic application or error, 4 cases from adverse reactions, and 1 case from an unknown cause. Asymptomatic children accounted for 75.5% of cases, but major clinical effects were observed in 5 patients. Those with serious effects were exposed to a range of benzocaine concentrations (7.5-20%), with 4 cases reporting methemoglobin levels between 20.2%-55%. Methylene blue was administered in 4 of the cases exhibiting major effects. CONCLUSION: The majority of exposures were accidental ingestions by young children. Most exposures resulted in minor to no effects. However, some patients required treatment with methylene blue and admission to a critical care unit. Therapeutic application by parents or caregivers may lead to adverse effects from these commonly available products.


Assuntos
Acidentes Domésticos/estatística & dados numéricos , Anestésicos Locais/administração & dosagem , Benzocaína/administração & dosagem , Metemoglobinemia/induzido quimicamente , Centros de Controle de Intoxicações/estatística & dados numéricos , Venenos/administração & dosagem , Administração Tópica , Anestésicos Locais/efeitos adversos , Benzocaína/efeitos adversos , California/epidemiologia , Pré-Escolar , Registros Eletrônicos de Saúde , Humanos , Lactente , Metemoglobinemia/tratamento farmacológico , Azul de Metileno/uso terapêutico , Venenos/efeitos adversos , Estudos Retrospectivos
11.
Sci Rep ; 7(1): 7912, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28801624

RESUMO

One of the hallmarks of acute inflammation is neutrophil infiltration of tissues. We investigated molecular mechanisms implicated in acute neutrophilic inflammation induced by the venom of a freshwater stingray (Potamotrygon cf. henlei) in mice. Ray venom induced early mobilization of neutrophil in the microvasculature of cremaster mice and infiltration of the peritoneal cavity 2 hours after injury, in a dose-response manner. IL-1ß, IL-6, TNF-α, and KC were produced. The neutrophilic infiltration did not occur in mice with ST2 receptor and MyD88 adapters neutralized, or in those with PI3K and p38 MAPK signaling blocked. Drastic reduction of neutrophil infiltration to peritoneal cavities was observed in ST2-/-, TLR2/TLR4-/-, MyD88-/-, TRIF-/- and IL-17A-/- mice, and a partial reduction was observed in IL-18R-/- mice. Mast cell Kit W(sh)/W(sh)-, AHR-, NLRP3-, ICE-, IL-1ß-, P2RX7-, CD39-, IL-17RA-, and TBX21 KO mice retain the ability to induce neutrophilia in peritoneal cavity after ray venom injection. IL-6 and TNF-α alone were insufficient for promote neutrophilia in the absence of ST2 signaling. Finally, abundant production of IL-33 by cardiomyocytes was observed. These results refine our understanding of the importance of the IL-33/ST2 axis and IL-33-producing cardiomyocytes in the early acute neutrophilia induced by freshwater stingray venoms.


Assuntos
Interleucina-33/metabolismo , Mastócitos/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Neutrófilos/imunologia , Venenos/toxicidade , Peçonhas/toxicidade , Animais , Citocinas/genética , Citocinas/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Camundongos , Camundongos Knockout , Cavidade Peritoneal/patologia , Intoxicação/patologia , Venenos/administração & dosagem , Transdução de Sinais , Rajidae , Peçonhas/administração & dosagem
12.
Artigo em Inglês | MEDLINE | ID: mdl-27321368

RESUMO

South Texas currently has the highest incidence of hepatocellular carcinoma (HCC) in the United States, a disease that disproportionately affects Latino populations in the region. Aflatoxin B1 (AFB1) is a potent liver carcinogen that has been shown to be present in a variety of foods in the United States, including corn and corn products. Importantly, it is a dietary risk factor contributing to a higher incidence of HCC in populations frequently consuming AFB1-contaminated diets. In a randomised double-blind placebo controlled trial, we evaluated the effects of a 3-month administration of ACCS100 (refined calcium montmorillonite clay) on serum AFB1-lysine adduct (AFB-Lys) level and serum biochemistry in 234 healthy men and women residing in Bexar and Medina counties, Texas. Participants recruited from 2012 to 2014 received either a placebo, 1.5 g or 3 g ACCS100 each day for 3 months, and no treatment during the fourth month. Adverse event rates were similar across treatment groups and no significant differences were observed for serum biochemistry and haematology parameters. Differences in levels of AFB-Lys at 1, 3 and 4 months were compared between placebo and active treatment groups. Although serum AFB-Lys levels were decreased by month 3 for both treatment groups, the low dose was the only treatment that was significant (p = 0.0005). In conclusion, the observed effect in the low-dose treatment group suggests that the use of ACCS100 may be a viable strategy to reduce dietary AFB1 bioavailability during aflatoxin outbreaks and potentially in populations chronically exposed to this carcinogen.


Assuntos
Aflatoxina B1/sangue , Silicatos de Alumínio/uso terapêutico , Bentonita/uso terapêutico , Cálcio/uso terapêutico , Venenos/sangue , Adulto , Aflatoxina B1/administração & dosagem , Silicatos de Alumínio/administração & dosagem , Bentonita/administração & dosagem , Bentonita/efeitos adversos , Biomarcadores , Cálcio/administração & dosagem , Argila , Método Duplo-Cego , Feminino , Humanos , Masculino , Venenos/administração & dosagem , Texas
13.
Sci Rep ; 6: 26809, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27229176

RESUMO

Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury.


Assuntos
Ciguatoxinas/toxicidade , Gânglios Espinais/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Traumatismos dos Nervos Periféricos/fisiopatologia , Venenos/toxicidade , Animais , Axotomia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciguatoxinas/análise , Gânglios Espinais/patologia , Gânglios Espinais/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Movimento/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Neurônios/patologia , Neurônios/fisiologia , Traumatismos dos Nervos Periféricos/patologia , Venenos/administração & dosagem , Recuperação de Função Fisiológica
14.
PLoS One ; 11(1): e0146712, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26812148

RESUMO

Invasive feral swine (Sus scrofa) cause extensive damage to agricultural and wildlife resources throughout the United States. Development of sodium nitrite as a new, orally delivered toxicant is underway to provide an additional tool to curtail growth and expansion of feral swine populations. A micro-encapsulation coating around sodium nitrite is used to minimize detection by feral swine and maximize stability for the reactive molecule. To maximize uptake of this toxicant by feral swine, development a bait matrix is needed to 1) protect the micro-encapsulation coating so that sodium nitrite remains undetectable to feral swine, 2) achieve a high degree of acceptance by feral swine, and 3) be minimally appealing to non-target species. With these purposes, a field evaluation at 88 sites in south-central Texas was conducted using remote cameras to evaluate preferences by feral swine for several oil-based bait matrices including uncolored peanut paste, black-colored peanut paste, and peanut-based slurry mixed onto whole-kernel corn. These placebo baits were compared to a reference food, whole-kernel corn, known to be readily taken by feral swine (i.e., control). The amount of bait consumed by feral swine was also estimated using remote cameras and grid boards at 5 additional sites. On initial exposure, feral swine showed reduced visitations to the uncolored peanut paste and peanut slurry treatments. This reduced visitation subsided by the end of the treatment period, suggesting that feral swine needed time to accept these bait types. The black-colored peanut paste was visited equally to the control throughout the study, and enough of this matrix was consumed to deliver lethal doses of micro-encapsulated sodium nitrite to most feral swine during 1-2 feeding events. None of the treatment matrices reduced visitations by nontarget species, but feral swine dominated visitations for all matrices. It was concluded that black-colored peanut paste achieved satisfactory preference and consumption by feral swine, and no discernable preference by non-target species, compared to the other treatments.


Assuntos
Venenos/administração & dosagem , Nitrito de Sódio/administração & dosagem , Sus scrofa , Animais , Animais Selvagens , Preferências Alimentares , Espécies Introduzidas , Controle da População , Texas
15.
BMC Public Health ; 15: 1167, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26602540

RESUMO

BACKGROUND: Attempted or non-fatal self-poisoning is common in Sri Lanka. To date, most preventive strategies have focused on limitation of access to toxic pesticides, which has reduced the rates of fatal self-poisoning. However the ongoing phenomenon of non-fatal self-poisoning indicates the need for exploration of alternate preventive strategies. Self-poisoning in Sri Lanka has been described as impulsive, with little premeditation, but the motivations associated with this act have not been studied in depth. This research describes the triggers and motivations associated with non-fatal self-poisoning in Sri Lanka. It is anticipated that the findings would help guide future preventive strategies. METHODS: Two studies were carried out, at Teaching Hospital Peradeniya, Sri Lanka, each using a different methodology - Study 1 consisted of qualitative semi-structured interviews, and Study 2 was a cross sectional survey. Both studies were conducted among those who had recently attempted self-poisoning, and explored associated triggers and motivations associated with the act of self-poisoning. There was no overlap between participants of the two studies. RESULTS: A total of 24 persons participated in the semi-structured interviews (Study 1), and 921 took part in the cross-sectional survey (Study 2). Interpersonal conflict was the most common trigger prior to the act of non-fatal self-poisoning. A mixture of motivations was associated with the act of self-poisoning, including intent to die, to escape, and difficulty tolerating distress associated with interpersonal conflict. CONCLUSIONS: Development of interpersonal skills and interpersonal problem solving skills, particularly in adolescents and young people, emerges as a key primary preventive strategy. Further, there is value in exploring and helping people to develop more adaptive strategies to cope with emotional distress associated with interpersonal conflict. While distress tolerance and interpersonal skill training strategies used in the West may be considered, it is also important to adapt and develop strategies suited to the local cultural background. Further research is needed to develop and evaluate such strategies, and findings may have implications not only to Sri Lanka but also for other countries in South Asia.


Assuntos
Relações Interpessoais , Motivação , Venenos/administração & dosagem , Estresse Psicológico/complicações , Tentativa de Suicídio/psicologia , Adaptação Psicológica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ásia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sri Lanka , Adulto Jovem
16.
J. venom. anim. toxins incl. trop. dis ; 20: 1-7, 04/02/2014. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484558

RESUMO

The L-amino acid oxidases (LAAOs) constitute a major component of snake venoms and have been widely studied due to their widespread presence and various effects, such as apoptosis induction, cytotoxicity, induction and/or inhibition of platelet aggregation, hemorrhage, hemolysis, edema, as well as antimicrobial, antiparasitic and anti-HIV activities. The isolated and characterized snake venom LAAOs have become important research targets due to their potential biotechnological applications in pursuit for new drugs of interest in the scientific and medical fields. The current study discusses the antitumor effects of snake venom LAAOs described in the literature to date, highlighting the mechanisms of apoptosis induction proposed for this class of proteins.


Assuntos
Animais , L-Aminoácido Oxidase/análise , Oxirredutases/análise , Venenos/administração & dosagem , Serpentes/classificação
17.
Artigo em Inglês | LILACS | ID: lil-724668

RESUMO

The L-amino acid oxidases (LAAOs) constitute a major component of snake venoms and have been widely studied due to their widespread presence and various effects, such as apoptosis induction, cytotoxicity, induction and/or inhibition of platelet aggregation, hemorrhage, hemolysis, edema, as well as antimicrobial, antiparasitic and anti-HIV activities. The isolated and characterized snake venom LAAOs have become important research targets due to their potential biotechnological applications in pursuit for new drugs of interest in the scientific and medical fields. The current study discusses the antitumor effects of snake venom LAAOs described in the literature to date, highlighting the mechanisms of apoptosis induction proposed for this class of proteins.


Assuntos
Animais , L-Aminoácido Oxidase/análise , Oxirredutases/análise , Venenos/administração & dosagem , Serpentes/classificação
19.
Cancer Causes Control ; 24(11): 1963-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23949201

RESUMO

PURPOSE: We investigated the effects of aflatoxin B1 (AFB1) intake, genetic polymorphisms of AFB1 metabolic enzymes, and interactions between the polymorphisms and intake of AFB1 with regard to the risk of gastric cancer in Korean. METHODS: The participants in the study included 477 gastric cancer patients and 477 age- and sex-matched control subjects. Direct interviews and a structured questionnaire were used to determine the level of exposure to AFB1, and the GoldenGate assay and multiplex polymerase chain reaction were used for genotypic analyses of the cytochrome P450 1A2 (CYP1A2), cytochrome P450 1E1, epoxide hydrolase 1, and glutathione S-transferase genes. RESULTS: The probable daily intake of AFB1 was significantly higher among gastric cancer patients than among control subjects (cases vs. controls: 1.91 ± 0.87 vs. 1.65 ± 0.72 ng/kg bw/day, p < 0.0001), and increased AFB1 intake was significantly associated with an elevated risk of gastric cancer (odds ratio 1.94; 95 % confidence interval 1.43-2.63). However, genetic polymorphisms of AFB1 metabolic enzymes were not associated with gastric cancer, with the exception of CYP1A2. Moreover, there was no interaction between AFB1 intake and the genotypes of metabolic enzymes that affect gastric cancer risk. CONCLUSIONS: Our results suggest that dietary AFB1 exposure might be associated with a risk of gastric cancer. However, the effect of AFB1 on gastric carcinogenesis may not be modulated by genetic polymorphisms of AFB1 metabolic enzymes.


Assuntos
Aflatoxina B1/administração & dosagem , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2E1/genética , Epóxido Hidrolases/genética , Glutationa Transferase/genética , Neoplasias Gástricas/genética , Aflatoxina B1/envenenamento , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Inquéritos Epidemiológicos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Venenos/administração & dosagem , Polimorfismo de Nucleotídeo Único , República da Coreia , Fatores de Risco , Neoplasias Gástricas/etnologia , Neoplasias Gástricas/etiologia
20.
PLoS One ; 8(3): e57658, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23536767

RESUMO

BACKGROUND: Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation. METHODOLOGY AND PRINCIPAL FINDINGS: Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin. CONCLUSIONS/SIGNIFICANCE: It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings.


Assuntos
Antídotos/farmacologia , Venenos de Cnidários/antagonistas & inibidores , Venenos de Cnidários/toxicidade , Venenos/toxicidade , Pele/efeitos dos fármacos , Pele/patologia , Tetraciclina/farmacologia , Animais , Linhagem Celular , Venenos de Cnidários/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/enzimologia , Masculino , Metaloproteases/antagonistas & inibidores , Camundongos , Células NIH 3T3 , Venenos/administração & dosagem , Coelhos
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