雪卡毒素人工抗原合成及鉴定

雪卡毒素是一种存在于珊瑚鱼中的海洋毒素,极低剂量就会引起中毒。为了建立雪卡毒素的免疫分析方法,必须合成其人工抗原才能制备抗体。以雪卡毒素的结构类似物莫能菌素为半抗原,采用琥珀酸酐法将其改造成莫能菌素-琥珀酰半酯（MON-HS）,再用混合酸酐法将其与大分子载体牛血清蛋白（BSA）和卵清蛋白（OVA）偶联,成功制备出了雪卡毒素人工抗原MON-HS-BSA和MON-HS-OVA。以MON-HS-BSA为免疫抗原免疫Balb/c小鼠,以MON-HS-OVA为包被抗原,用间接竞争酶联免疫吸附法（Ci-ELISA）检测到小鼠血清中产生了雪卡毒素的抗体,说明已成功合成雪卡毒素人工抗原,该抗原可用于制备雪卡毒素单克隆抗体。      

海洋鱼类雪卡毒素的研究进展

雪卡毒素(Ciguatoxin,CTX)是一种重要的海洋鱼类毒素。近年来,雪卡毒素引起的食物中毒事件在我国呈增多趋势。本文通过对雪卡毒素(Ciguatoxin,CTX)的来源、分布、传播载体、化学与毒性特性、中毒爆发情况和检测技术等进行综述,以期为我国建立有效的鱼类雪卡毒素检测方法、构建可靠的雪卡毒素监测预警技术体系,保障消费者的食用安全提供参考。      

一起雪卡毒素中毒事件中裸胸鳝毒性的研究

目的研究厦门一起引发食物中毒的裸胸鳝毒性及种类,以预防雪卡毒素中毒。方法对中毒事件进行流行病学调查,采集裸胸鳝样品共5份,采用小鼠生物法、雪卡毒素免疫膜检测试剂盒检测毒性大小,高效液相色谱-串联质谱法测定太平洋雪卡毒素(P-CTX-1),同时提取中毒鱼肉组织中的mtDNA,PCR技术扩增细胞色素b(Ctyb)后测序鉴定中毒鱼种。结果小鼠生物法试验检测5份样品,鱼肉毒性为无毒性(ND)～0.052 MU/g,内脏毒性为ND～0.23 MU/g;高效液相色谱-串联质谱法未检出P-CTX-1。5种鱼种经鉴定均为裸胸鳝属(Gymnothorax),其中中毒鱼种经基因测序为波纹裸胸鳝(Gymnothorax undulates)。结论引发该起食物中毒的是一种含有雪卡毒素的波纹裸胸鳝。     

吃深海鱼，当心雪卡毒素中毒

近年来．广州、深圳、香港、汕头等地相继发生几百人食用深海鱼中毒的事件．广州卫生监督部门为此发出了“慎食深海鱼“的通知。吃深海鱼为什么会引起中毒呢？吃深海鱼引起中毒的原因现已查明．是部分深海鱼中含有雪卡毒素所致。     

吃石斑鱼小心“雪卡毒”

《广州日报》不久前报道：一市民赴宴吃了深海石斑鱼后中“雪卡毒”．最终被鉴定为十级伤残。曾参与抢救石斑鱼中毒的医生。广东省汕头市中心医院ICU主治医师张淇钏介绍．雪卡毒素并非鱼类与生俱来的,属获得性毒素。含有雪卡毒素的藻类黏附在深海的珊瑚表面,小鱼吃下有毒海藻后,大鱼再吃下小鱼,毒素随之积聚在大鱼体内,就这样通过食物链富集浓缩。     

加拿大:不建议给1岁以下婴儿喂食蜂蜜

正婴儿肉毒中毒症非常罕见,对1岁以下婴儿可引起严重的症状,主要原因为进食含有肉毒梭状芽胞杆菌(简称肉毒梭菌)毒素污染的食物而引起的急性中毒性疾病。若不及时抢救,则病死率很高。肉毒梭菌存在于经加热杀菌及未经杀菌的蜂蜜中,因此,不要给1岁以下婴儿喂食蜂蜜是非常重要的。因肉毒杆菌孢子即使经加热(调理、蒸煮等)也难以杀灭,故同样不建议在婴儿用食品甜味剂中添加蜂蜜。     

液相色谱-串联质谱检测鱼类及海鲜类调味品中的雪卡毒素

建立了液相色谱-串联质谱分析深海鱼及鱼酱中太平洋雪卡毒素(P-CTX-1,P-CTX-2,P-CTX-3)的方法。用甲醇/正己烷(80/20)溶液对太平洋雪卡毒素(P-CTX-1,P-CTX-2,P-CTX-3)进行提取,C18、硅胶固相萃取柱净化后,采用液相色谱分离,以电喷雾离子源正离子选择反应监测模式进行质谱分析。三种太平洋雪卡毒素(P-CTX-1,P-CTX-2,P-CTX-3)在1.0~20μg/L线性良好,相关系数0.99。虎鳗肌肉空白样品添加太平洋卡毒素的回收率均在70.1%~93.5%(n=6),精密度(RSD)在2.9%~15.3%。鱼肉组织中太平洋雪卡毒素(P-CTX-1,P-CTX-2,P-CTX-3)的检出限均为0.1μg/kg。     

一起腌制蟛蜞引起的食物中毒

一起腌制蟛蜞引起的食物中毒郑能雄福州市卫生防疫站（３５０００４）１９９５年９月２０日，福州市郊某村发生一起进食变质的腌制蟛蜞引起的暴发性食物中毒，当天上午进食８６人，中毒７５人，罹患率８７．２１％。流行病学调查、临床症状和实验室检验结果表明食物中毒的...     

一起误食光硬皮马勃中毒事件调查

目的 对2019年9月4日发生在云南省楚雄彝族自治州的一起误食光硬皮马勃中毒事件进行调查分析,明确中毒原因,总结中毒特点及救治方法,为该蘑菇中毒事件的处置提供借鉴。方法 收集中毒病例资料、进行流行病学调查、对蘑菇样品进行形态学和分子生物学鉴定。结果 2例患者各进食了约50 g购买于市场的马勃后,出现了腹痛、恶心、呕吐、腹泻及低血压的症状,潜伏期0.5～1 h,经过对症治疗后好转出院。蘑菇标本经形态学和分子生物学鉴定为光硬皮马勃。结论 此次事件是因误食光硬皮马勃引起的急性中毒事件。光硬皮马勃与可食用的云南硬皮马勃外形相似,常因误食而中毒。鉴于很多毒蘑菇与一些食用菌形态上极为相似而导致误采误食,建议不要随意采食野生蘑菇。     

广东省首起误食剧毒裂皮鹅膏菌所致食物中毒死亡分析

目的调查分析本次食物中毒事件的流行病学特征,鉴定引起食物中毒的毒蘑菇种类,提出防控措施,预防食物中毒事件的再次发生。方法通过制定病例定义及病例搜索、病例访谈、食谱调查、现场采样和毒蘑菇的形态学鉴定等方法对食物中毒事件进行分析。结果 5名外来务工人员自行采摘并进食野生蘑菇约150 g,8.3~10 h后出现恶心、呕吐、腹泻、腹痛等胃肠炎症状,临床检测提示病例肝功能损害。经洗胃、血浆置换、放置活性炭吸附、补液及护肝护胃等清除毒物和对症治疗后,其中2例病例出现假愈期,1 d后病情又急剧恶化。随后几天所有病例均出现肝功能衰竭,并因多器官功能衰竭而死亡,罹患率和病死率均为100%(5/5)。食谱调查显示除了自行采摘的蘑菇外未见其他可以引起中毒的食物,经形态学鉴定为裂皮鹅膏菌。本起事件系由于病例误食了M公园山上采集的野生蘑菇所致的食物中毒,毒蘑菇为剧毒的裂皮鹅膏菌。结论误食裂皮鹅膏菌中毒在广东省为首次报道,本起事件对裂皮鹅膏菌中毒的疾病自然史进行了较为全面的描述。该菌与部分可食菌类外观极其相似,难以分辨极易误食,需进一步加强健康教育,提醒民众不要采食野生蘑菇是预防毒蘑菇中毒最根本的方法。     

Ciguatera: recent advances but the risk remains

Ciguatera is an important form of human poisoning caused by the consumption of seafood. The disease is characterised by gastrointestinal, neurological and cardiovascular disturbances. In cases of severe toxicity, paralysis, coma and death may occur. There is no immunity, and the toxins are cumulative. Symptoms may persist for months or years, or recur periodically. The epidemiology of ciguatera is complex and of central importance to the management and future use of marine resources. Ciguatera is an important medical entity in tropical and subtropical Pacific and Indian Ocean regions, and in the tropical Caribbean. As reef fish are increasingly exported to other areas, it has become a world health problem. The disease is under-reported and often misdiagnosed. Lipid-soluble, polyether toxins known as ciguatoxins accumulated in the muscles of certain subtropical and tropical marine finfish cause ciguatera. Ciguatoxins arise from biotransformation in the fish of less polar ciguatoxins (gambiertoxins) produced by Gambierdiscus toxicus, a marine dinoflagellate that lives on macroalgae, usually attached to dead coral. The toxins and their metabolites are concentrated in the food chain when carnivorous fish prey on smaller herbivorous fish. Humans are exposed at the end of the food chain. More than 400 species of fish can be vectors of ciguatoxins, but generally only a relatively small number of species are regularly incriminated in ciguatera. Ciguateric fish look, taste and smell normal, and detection of toxins in fish remains a problem. More than 20 precursor gambiertoxins and ciguatoxins have been identified in G. toxicus and in herbivorous and carnivorous fish. The toxins become more polar as they undergo oxidative metabolism and pass up the food chain. The main Pacific ciguatoxin (P-CTX-1) causes ciguatera at levels=0.1 microg/kg in the flesh of carnivorous fish. The main Caribbean ciguatoxin (C-CTX-1) is less polar and 10-fold less toxic than P-CTX-1. Ciguatoxins activate sodium ion (Na ) channels, causing cell membrane excitability and instability. Worldwide coral bleaching is now well documented, and there is a strong association between global warming and the bleaching and death of coral. This, together with natural environmental factors such as earthquakes and hurricanes, and man-made factors such as tourism, dock construction, sewage and eutrophication, may create more favourable environments for G. toxicus. While low levels of G. toxicus are found throughout tropical and subtropical waters, the presence of bloom numbers is unpredictable and patchy. Only certain genetic strains produce ciguatoxins, and environmental triggers for increasing toxin production are unknown.     

Caribbean ciguatoxin profile in raw and cooked fish implicated in ciguatera

A cooked meal remnant and uncooked portion of a Caribbean barracuda suspected in ciguatera fish poisoning were examined for the presence of ciguatoxins (CTX). Samples were analysed using a tiered method of CTX analysis consisting of in vitro cell (N2a) assay to assess composite toxicity and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for structural confirmation. Meal remnant and uncooked fish extracts were cytotoxic by N2a cell assay and Caribbean ciguatoxin congener C-CTX-1 was structurally confirmed. Sample extracts were fractionated by LC and fractions analysed by the cell assay. The cytotoxicity profiles of cooked meal remnant and uncooked fish were similar. Cytotoxicity-guided LC-MS/MS analyses identified several CTX congeners contributing to the composite toxicity of the samples. C-CTX-1 was a major contributor, supporting its utility as a biomarker of Caribbean ciguatoxic fish.     

河北省一起误食黄盖鹅膏中毒事件的调查报告

目的调查分析河北省一起食物中毒事件的流行病学特征,鉴定引起中毒的野生蘑菇种类,提出有效防控措施。方法运用现场流行病学调查、形态学鉴定和分子生物学鉴定等方法对本起中毒事件进行分析。结果本次误食野生毒蘑菇中毒事件发病11人,死亡3人,病死率为27.27%。采集施工现场野生蘑菇,结合形态学和分子生物学鉴定方法,鉴定为黄盖鹅膏。结论该中毒事件为河北省首次明确报道的黄盖鹅膏中毒,今后工作应注重加强监测预警和宣传教育,提醒广大市民不要采食野生蘑菇,以防中毒。     

鲀毒鱼毒素检测及物种鉴定技术研究进展

鲀毒鱼引起的河鲀毒素(tetrodotoxin,TTX)中毒是中国沿海地区食物中毒致死的主要原因之一.河鲀毒素中毒发病迅速,至今尚无特效药,因此,通过检测TTX含量或鉴定携带TTX的物种可以更好地进行TTX中毒的风险分析、管理和控制.本文综述了鲀毒鱼TTX的检测技术以及鲀毒鱼物种鉴定的方法,以期能预警并减少鲀毒鱼引起的...     

鲭鱼品质评价及品质变化与组胺含量研究进展

海水鱼类的新鲜度体现了鱼肉的可食用价值,海水鱼中的青皮红肉鱼类含有较高的组氨酸,会因保存不当导致体内组胺含量升高,对消费者健康产生危害。组胺是一种食源性化学危害,易导致过敏人群产生中毒现象。组胺中毒又称为鲭鱼中毒,是组胺引起毛细血管扩张和支气管收缩所致,研究表明鲭科鱼类的组氨酸含量高,组氨酸会在产组胺微生物的组氨酸脱羧酶的作用下产生组胺,判定组胺中毒的最有效的方法是检测鲭鱼体内的组胺含量,低水平的组胺并不会对人体产生危害,组胺摄入量过多会对人体产生危害,组胺已成为评价鲭鱼品质的标准之一。本文主要对鲭鱼品质的感官评定和理化评定(组胺、K值、挥发性盐基氮等)方式进行综述,并对组胺产生的影响因素如微生物、温度、鱼的种类等进行综述,为鲭鱼品质鉴定和组胺含量的控制提供依据。     

Caribbean Ciguatoxin-1 stability under strongly acidic conditions: Characterisation of a new C-CTX1 methoxy congener

ABSTRACT

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.     

云南省2015—2020年野¬生蕈中毒流行特征及趋势预测

目的 探讨云南省2015—2020年野生蕈中毒事件的发病规律和特点,为制定预防和控制措施提供依据。方法采用描述流行病学方法,对云南省野生蕈中毒事件进行分析;采用季节趋势模型对云南省2021年每月野生蕈中毒事件数进行预测。结果云南省2015-2020年共报告野生蕈中毒事件3428起,中毒13931人,死亡180人;6-8月为云南省野生蕈中毒的高峰期,报告起数占总数的85.0%;报告起数前三位的州市为：文山、玉溪和楚雄,报告起数占总数的48.7%;家庭是野生蕈中毒高发的场所,事件报告数、发病人数、死亡人数分别占总数的91.7%、85.2%和93.9%。采用季节趋势模型对云南省2021年野生蕈中毒事件趋势进行预测,野生蕈中毒事件继续呈上升趋势,中毒高峰为6-8月。结论 野生蕈中毒是云南省危害较为严重的公共卫生事件,应根据其高发季节、高发地区、高发场所,提前制定有效的防控措施,广泛开展预防野生蕈中毒知识宣传教育,有效地降低野生蕈中毒事件的发生。季节趋势模型对云南省野生蕈中毒事件的拟合效果较好,可以应用于预测。     

Identification of ciguatoxins in Hawaiian monk seals Monachus schauinslandi from the Northwestern and Main Hawaiian Islands

Ciguatoxins are potent algal neurotoxins that concentrate in fish preyed upon by the critically endangered Hawaiian monk seal (Monachus schauinslandi). The only report for Hawaiian monk seal exposure to ciguatoxins occurred during a 1978 mortality event when two seal liver extracts tested positive by mouse bioassay. Ciguatoxins were thus proposed as a potential threat to the Hawaiian monk seal population. To reinvestigate monk seal exposure to ciguatoxins we utilized more selective detection methods, the Neuro-2A cytotoxicity assay, to quantify ciguatoxin activity and an analytical method LC-MS/MS to confirm the molecular structure. Tissue analysis from dead stranded animals revealed ciguatoxin activity in brain, liver, and muscle, whereas analysis of blood samples from 55 free-ranging animals revealed detectable levels of ciguatoxin activity (0.43 to 5.49 pg/mL P-CTX-1 equiv) in 19% of the animals. Bioassay-guided LC fractionation of two monk seal liver extracts identified several ciguatoxin-like peaks of activity including a peak corresponding to the P-CTX-3C which was confirmed present by LC-MS/MS. In conclusion, this work provides first confirmation that Hawaiian monk seals are exposed to significant levels of ciguatoxins and first evidence of transfer of ciguatoxin to marine mammals. This threat could pose management challenges for this endangered marine mammal species.