简单异尖线虫环介导等温扩增(LAMP)鉴定方法的建立和应用

目的 建立快速鉴定简单异尖线虫的环介导等温扩增方法(LAMP). 方法 根据简单异尖线虫ITS保守区域的基因序列设计特异性引物进行LAMP扩增,对反应体系中dNTPs、Mg2+、Betaine和2对引物的浓度,以及反应温度、反应时间等进行优化;在优化后的体系下,将10倍比稀释的简单异尖线虫ITS序列重组质粒进行灵敏性试验;用典型异尖线虫、对盲囊线虫、针蛔线虫对该方法进行特异性试验;并用7份简单异尖线虫样品进行验证. 结果 LAMP的最佳反应体系为0.8 mmoL/L dNTPs、10 mmol/L Mg2+、0.8 mmoL/L Betaine、0.2μmol/L外引物、1.6μmoL/L内引物、8 U Bst DNA聚合酶大片段以及适量的模板,反应温度为62℃,反应时间为60 min;检测简单异尖线虫的灵敏度达到10拷贝/μl,且对典型异尖线虫、对盲囊线虫、针蛔线虫无交叉反应;7份简单异尖线虫样品经LAMP验证均为阳性.结论 LAMP方法灵敏性高、特异性强,并且操作简便、成本低,是鉴定简单异尖线虫的有效手段.     

福建省沿海鱼类异尖线虫幼虫感染情况调查及虫种鉴定

目的了解福建省沿海鱼类异尖线虫幼虫感染情况。方法于2016年1月-2018年12月在福建省沿海3大渔场(闽东、闽中和闽南)随机采购海鱼,鉴定鱼种后,解剖镜下分离海鱼内脏和肌肉内的异尖线虫幼虫,光学显微镜下鉴定虫种。统计不同鱼种、不同脏器中异尖线虫幼虫分布情况。结果共解剖海鱼32种810尾,检出异尖线虫幼虫感染19种277尾,异尖线虫幼虫感染率为34.2%,平均感染度为11.2条/尾。带鱼、马鲛鱼、海鲫鱼和包公鱼等4个鱼种异尖线虫幼虫感染率较高,分别为85.6%(95/111)、 63.5%(47/74)、36.7%(67/162)和36.7%(18/49),平均感染度分别为23.1、 7.6、 4.5和4.2条/尾。不同鱼种体内异尖线虫幼虫的分布不同,多数寄生于海鱼的肠系膜及肠壁、体腔和胃壁,其次是肝、胰脏器、生殖器,肌肉中极少发现。检获的异尖线虫鉴定出4种异尖线虫幼虫,分别是异尖属Ⅰ型幼虫(Anisakis typeⅠ)、异尖属Ⅱ型幼虫(Anisakis typeⅡ)、厦门宫脂线虫(Hysterothylacium amoyense)幼虫和宫脂线虫(Hysterothylacium sp.)幼虫。结论福建省沿海海鱼类异尖线虫幼虫感染率较高,应加强防控。     

福建省闽东渔场海鱼异尖线虫感染调查

目的 了解福建省闽东渔场海洋鱼类异尖线虫感染情况,为制定异尖线虫病控制策略、保障食品安全提供依据。方法 2021年9—12月在福建省闽东渔场沿海蕉城区、福鼎市、霞浦县随机收集海鱼样本,解剖获取鱼腹腔内容物,在体视显微镜下挑取寄生虫,并在镜下根据异尖线虫形态特征鉴定虫种,计算异尖线虫感染率和感染度。结果 共解剖海鱼24种177尾,其中16种73尾海鱼检出异尖线虫,鱼种检出率为66.7%、海鱼总感染率为41.2%;感染度为1～148条/尾,平均感染度为14.3条/尾。异尖线虫感染率较高的鱼种为鳓鱼(5/5)、鮸鱼(3/3)、包公鱼(2/2)、马鲛鱼(12/13)、带鱼(19/23)、白姑鱼(6/11)、海鲫鱼(14/27),平均感染度依次为9.2、2.7、4.5、10.9、39.2、4.5、2.1条/尾。检出的异尖线虫幼虫经鉴定为异尖线虫属和宫脂线虫属。结论 福建省闽东渔场海洋鱼类异尖线虫感染率较高,应加强饮食健康宣传,防止人群异尖线虫病发生。     

PCR-RFLP技术在寄生虫分类鉴定中的应用

PCR-限制性片段长度多态性(PCR-RFLP)技术是一种简便、快速的鉴定寄生虫种类的方法.目前,PCR-RFLP技术广泛应用于寄生虫学领域.该文综述了PCR-RFLP技术在医学原虫和蠕虫分类鉴定中的应用现状.     

异尖科线虫线粒体基因组序列的生物信息学分析

目的了解异尖科线虫线粒体基因组序列特性及其在分子分类和系统进化研究中的价值。方法从NCBI网站获得5种异尖科线虫的线粒体基因组序列数据,应用ClustalW、MEGA7、ARWEN进行核苷酸与编码氨基酸比对;利用ESPript和PyMOL软件分析COX1蛋白一级结构,比较各蛋白三级结构模型。结果异尖线虫科线粒体DNA为双链闭环分子,长度为1.32～1.40kb。共有36个以相同方向排列的基因,其中编码蛋白质的基因12个,编码tRNA的基因22个(含亮氨酸-tRNA和丝氨酸-tRNA基因各2个,其余18种氨基酸tRNA各1个),编码rRNA的基因2个(分别为16S核糖体RNA(rRNA)和12SrRNA)。在12个蛋白编码基因中,CYTB和Nad2基因进化速率快,而cox1和nad4L基因则保守。线粒体tRNA长度为52～65bp,数目在6～9个之间,其中布兰地线虫(A.berlandi)的tRNA数目较多,为9个,而对盲囊线虫(C.ogmorhini)和简单异尖线虫(A.simplex)均为6个。tRNA二级结构多为经典的三叶草结构,少数为D-loop结构。简单异尖线虫与派氏异尖线虫(A.pegreffii)亲缘关系较近,拟地新线虫(P.decipiens)和简单异尖线虫与派氏异尖线虫的亲缘关系较远,对盲囊线虫与以上各虫种的亲缘关系较远。编码蛋白序列同源性比对显示,对盲囊线虫的COX1与其他4种异尖线虫差异较大,有17个氨基酸与其他4种不相同。氨基酸序列三级结构比对显示,对盲囊线虫的COX1有两处位点的折叠与其他线虫存在差异。结论异尖科线虫线粒体基因组分布均一,排列紧密,种间编码的蛋白质序列差异较小。A.pegreffii和A.simplex与A.berlandi的同源性较高,COX1可以作为异尖科线虫中重要的标志性蛋白。     

异尖线虫和异尖线虫病

异尖线虫的第3期幼虫寄生于某些海栖鱼类,人因摄食含有活幼虫的鱼肉或鱼内脏而感染,称为异尖线虫病。据Van Thiel等(1960)报告,Straub于1955年首次在荷兰发现本病,他从生吃鲱鱼后引起肠梗阻而作剖腹术患者的肠切除标本内,发现了钻入粘膜内的幼虫,后经鉴定为异尖线虫幼虫。异尖线虫虽不能在人体内发育为成虫,但它的幼虫引起的内脏幼虫移行症(V.L.M.),是     

东台市市售海鱼中异尖线虫感染调查

目的　掌握东台市市售海鱼中异尖线虫感染现状,为评估人群异尖线虫感染风险提供依据。方法　于2018年采集东台市海域捕捞且在当地销售的未经加工的新鲜海鱼,称重后解剖检测异尖线虫（含包囊）。计算海鱼异尖线虫感染率和感染度,分析异尖线虫感染海鱼质量和异尖线虫感染度间的相关性。结果　采集的5种海鱼中有4种（带鱼、马鲛鱼、鲐鱼、小黄鱼）检出异尖线虫。累计采集的149尾海鱼样本中,78尾感染异尖线虫,总感染率为52.35%,带鱼、马鲛鱼、墨鱼、鲐鱼、小黄鱼感染率分别为100.00%（28/28）、30.00%（9/30）、0（0/30）、53.33%（16/30）、80.65%（25/31）。共检出异尖线虫1 049条,总感染强度为13.45条/尾。Spearman秩相关检验显示,带鱼质量与异尖线虫感染度成正相关（rs = 0.38,P = 0.047）;其他鱼类质量和异尖线虫感染度无相关性。结论　东台市近海海域鱼类存在较高异尖线虫感染率,应进一步加大宣传教育力度,倡导市民养成健康安全的饮食习惯。     

2021年烟台市近海海鱼异尖线虫感染率及居民异尖线虫病防治知识知晓率调查

目的 了解2021年山东省烟台市近海海鱼异尖线虫感染率和当地居民异尖线虫病相关知识知晓情况,为制定异尖线虫病防控措施提供参考依据。方法 2021年11月,于山东省烟台市顺鑫港口购买海鱼,检测海鱼异尖线虫感染情况,并分析不同鱼种、不同部位异尖线虫感染率。采用Spearman秩相关分析海鱼体长和体质量与异尖线虫感染度间的相关性,对当地居民饮食习惯和异尖线虫病防治知识知晓率进行问卷调查。结果 共解剖海鱼20种201尾,其中11种77尾检出异尖线虫,鱼种异尖线虫感染检出率为55.00%(11/20)、海鱼总感染率为38.31%(77/201);异尖线虫感染阳性海鱼中累计检出异尖线虫3 468条,平均感染度为45.04条/尾。Spearman秩相关结果显示,鮟鱇鱼体长(r_s=0.74,P <0.05)和体质量(r_s=0.79,P <0.01)与异尖线虫感染度呈正相关,比目鱼体长与感染度呈正相关(r_s=0.68,P <0.05),其他种类海鱼体长、体质量与异尖线虫感染度均无相关性。问卷调查结果显示,53.38%男性...     

海鱼传播的人兽共患寄生虫病——异尖线虫病

<正> 异尖线虫病(anisakiasis)是寄生线虫异尖亚科中,某些属的幼虫侵入人的胃肠粘膜而引起的寄生虫病。异尖线虫成虫寄生于海栖哺乳动物,其幼虫寄生于某些海栖鱼类。人畜可因摄食含有活幼虫的海鱼而感染,因此属于人兽共患寄生虫病。1955年,Strauh首次在荷兰发现本病。他从生吃海鱼引起肠梗阻患者的肠切片中,发现粘膜内的虫体,经鉴定为异尖线虫     

异尖线虫过敏原研究进展

异尖线虫（Anisakis spp．）幼虫是重要的人兽共患寄生虫病病原体,呈世界性分布,为我国禁止入境的二类寄生虫。引起异尖线虫病的主要病原体为简单异尖线虫复合种A．simplex complex,包括3个姊妹种（简单异尖线虫A．sireplex s．s．;派氏异尖线虫A．pegreffii和简单异尖线虫C型A．compleax C）。已有的研究报道显示,日本的异尖线虫病主要是由简单异尖线虫引起的;     

Asymptomatic gastroduodenal anisakiasis as the cause of anaphylaxis.

A great number of parasites have been reported in fish, but only a few of them are capable of infecting human beings. Anisakiasis or anisakidosis is caused by sea nematodes of the genus Anisakis, with the main implicated species being Anisakis simplex. Infection with Anisakis causes a wide spectrum of clinical manifestations, ranging from symptoms related to the upper and occasionally lower digestive tract to allergic manifestations, mainly urticaria and anaphylaxis. We report a case of asymptomatic gastroduodenal anisakiasis presenting as severe anaphylaxis.     

Endoscopic Findings and Clinical Manifestation of Gastric Anisakiasis

Objectives : To identify the endoscopic findings and clinical manifestations of anisakiasis, we studied 87 cases of gastric anisakiasis. Methods : Patient information was analyzed by means of patient records. The interval between the day of intake of Anisakis and endoscopic examination was determined in 86 cases. Then the endoscopic findings of each interval were elucidated. Results : Moderate to severe gastric mucosal edema tends to occur within 1 or 2 days after Anisakis infection, accompanied by leukocytosis. As to the sites of penetration of Anisakis, 55 % of cases were found in the greater curvature with severe mucosal edema. Among 87 cases, four patients experienced anisakiasis twice during the interval examined, and six patients had past histories of anisakiasis before the investigated interval. Conclusions : Gastric anisakiasis may be caused by an allergic reaction to the Anisakis antigen. There is a classic relationship between clinical and endoscopic findings and the interval after Anisakis administration. Anisakis usually is found in the greater curvature.     

Occurrence and prevalence of fish-borne Anisakis larvae in the spotted mackerel Scomber australasicus from Taiwanese waters

Anisakid nematodes have been found in a variety of marine fishes throughout the world and they are known to cause anisakiasis in human hosts. The present study investigated the prevalence of potentially zoonotic anisakid larvae in spotted mackerel caught from Taiwanese waters where fish represents an important food sources. Anisakis third-stage larvae (L3, n = 502) were isolated from 250 spotted mackerel Scomber australasicus. Anisakis L3 larvae were divided morphologically into two types, Anisakis type I larvae had a longer ventriculus and mucron while type II larvae had a shorter ventriculus and no mucron. Anisakis species were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) of the internal transcribed spacer (ITS) regions of ribosomal DNA and direct sequencing. A simple molecular taxonomic key, utilizing RFLP by two restriction enzymes HinfI and HhaI, enabled the differentiation of the genus Anisakis. The prevalence, mean intensity and mean abundance of Anisakis nematodes recorded for the total specimens were 72.8%, 2.8 (1–15) and 2.0 (0–15), respectively. Anisakis pegreffii was determined to be the dominant species (prevalence = 57.2%) and important agent of human anisakiasis. A recombinant genotype (Anisakis simplex sensu stricto × A. pegreffii) was identified as the subdominant species (25.3%) followed by Anisakis typica (10%), Anisakis physeteris (4.0%), Anisakis paggiae (3.0%) and Anisakis brevispiculata (0.5%). The topology of the maximum likelihood and neighbor-joining trees show two well supported clades: one includes the species of A. pegreffii and the other includes A. paggiae, A. physeteris and A. brevispiculata, while A. typica has basal position to all other Anisakis spp. analyzed. This study advances our knowledge of the prevalence of different Anisakis spp. in the spotted mackerel from Taiwanese waters, which is helpful for monitoring the fish populations throughout a diverse array of aquatic ecosystems. More importantly, we provide the concise characterization of multiple Anisakis spp. by PCR–RFLP, which could also be applicable for the rapid diagnosis of human anisakiasis.     

南海,渤海鱼类简单异尖线虫幼虫感染的调查

目的：为了解我国南海、渤海各种鱼类中人体异尖线虫病的主要致病原——简单异尖线虫幼虫的感染状况而进行本调查。方法：取南海８８个鱼种３８９尾、渤海２０个鱼种４７１尾，分别测定体长及体重后解剖鱼体进行检查。检获的虫体清洁后用７０％酒精固定，用甘油酒精透明，在显微镜下鉴定。结果：南海部分检获幼虫的鱼种占被检鱼种数的６０．２％（５３／８８），阳性鱼种检得幼虫者占阳性鱼种的５３．６％（１４２／２６５），占所检鱼总尾数的３６．５％（１４２／３８９）；渤海部分检出幼虫的１１个鱼种占所检鱼种的５５％（１１／２０），阳性鱼种总检鱼数３７８尾中，检得幼虫者占阳性鱼种５０．５％（１９１／３７８），占所检鱼总尾数的４０．５％（１９１／４７１）。结论：两个海域中鱼类简单异尖线虫幼虫的感染率都相当高，因此凡生食本文所列的阳性海鱼时，不应疏忽对异尖线虫病的预防。以上在流行病学和食品卫生方面均有重要意义。     

Anisakiasis confirmed by radiography of the large intestine

As yet, there has been no report of acute anisakiasis of the large intestine diagnosed by radiographic demonstration of the larvae. We present such a case, in which roentgenologic examination revealed Anisakis larvae in the ascending colon.     

Natural products:Perspectives in the pharmacological treatment of gastrointestinal anisakiasis

Objective: To evaluate the activity of different natural products against L3 larvae of Anisakis type I. Methods: Information on investigations into the activity of natural products against the L3 larvae of Anisakis simplex was collected from scientific journals, books, theses and reports via a library and electronic search(using Pubmed, Scopus, Medline, Web of Science and Science Direct). The search terms included: natural products, medicinal plants, essential oils, terpenic derivatives, Anisakis, antinematodal activity. Results: In the literature reviewed numerous papers were found concerning the in vitro and in vivo activity against Anisakis type I of various natural products(plant extracts, essential oils and their major components). Analysis of the results showed that in vitro tests the Melaleuca alternifolia essential oil and the ar-turmerone isolated from Curcuma longa displayed the greatest activity. In vivo, the most active compound was perillaldehyde, the main component of Perilla frutescens essential oil. Conclusions: This study shows that some natural products exhibited promising antianisakis properties.     

Gastroallergic anisakiasis: findings in 22 patients

BACKGROUND AND AIMS: Ingestion of Anisakidae larvae in raw seafood may cause anisakiasis. However, despite the high level of consumption of seafood in Spain, only a few cases of anisakiasis have been reported until now. Anisakis simplex can cause allergic reactions in sensitized patients as a result of its parasitism in the gastrointestinal tract. The purpose of this study was to analyse the clinical findings in 22 patients with gastroallergic anisakiasis. METHODS: Patients with allergic and/or gastric symptoms after seafood ingestion were evaluated in the emergency room of the La Paz General University Hospital. Skin testing for Anisakis simplex and tests on the implicated seafood were performed and amounts of serum-specific immunoglobulin E were assessed. A gastroscopy was performed in those patients with severe allergic or/and persistent gastric symptoms after ingestion of raw or undercooked seafood. RESULTS: Twenty-two patients were diagnosed with gastroallergic anisakiasis in 1 year. Most patients presented to the emergency room of our hospital with allergic symptoms. Gastric symptoms were usually moderate. Gastroscopy revealed local mucosal oedema and gastric erosion at the point of fixation. Two or more worms were detected in three patients. The mean time of latency of allergic symptoms was 5 h, while the mean time for gastric symptoms was 3 h. CONCLUSION: Anisakis simplex parasitism was the causative agent of allergic and gastric symptoms. Gastroallergic anisakiasis appears to be a relatively common disease, that may have been underdiagnosed.     

A case of human anisakiasis in Kamchatka

The clinical symptoms of intestinal anisakiasis, the location of the larvae of nematodes in the intestine, and changes of the organ at the site of helminthic attachment are described. The causative agent of this parasitic disease has been detected. This is Anisakis sp. L III.