Identification and characterization of a cathepsin L-like cysteine protease from Gnathostoma spinigerum

Gnathostoma spinigerum is a causative agent of human gnathostomiasis, a common parasitic disease involving skin and visceral organs, especially the central nervous system. In this study, we identified a cDNA encoding a cathepsin L-like cysteine protease (GsCL1) from the lambdaZAP cDNA library of G. spinigerum advanced third-stage larva (aL3) and characterized the biochemical properties of the recombinant enzyme. The cloned cDNA of 1484bp encoded 398 amino acids which contained a typical signal peptide sequence (23 amino acids), a pro-domain (156 amino acids), and a mature domain (219 amino acids) with an approximate molecular weight of 24kDa. The deduced amino acid sequence of GsCL1 gene showed 53-64% identity to cathepsin L proteases of various organisms including a cathepsin L family member (cpl-1) of Caenorhabditis elegans. Recombinant proGsCL1 expressed in Pichia pastoris showed typical biochemical characteristics of cysteine proteases. The expressed enzyme displayed optimal protease activity toward Z-Phe-Arg-AMC substrate at pH 6.0 but not toward Z-Arg-Arg-AMC. The activity was sensitive to cysteine protease inhibitors E-64 and K11777. The preference for large hydrophilic and aromatic residues in the P2 position (I, L, F, W, U, V) was typical of cathepsin L proteases. Mouse anti-GST-proGsCL1 serum showed reactivity with 35-, 38- and 45-kDa proteins in the aL3 extracts. These proteins were shown to localize inside the intestinal cells of aL3.     

A rare case of cutaneous larva migrans due to Gnathostoma sp

A 28-year-old lady presented with recurrent erythematous skin lesions in different parts of the body for 3 months. There were several episodes of worm coming out of the lesions. Examination of the worms in the parasitology laboratory revealed it to be a larva of Gnathostoma sp. She was advised treatment with Albendazole for 21 days, and there was no recurrence of lesions.     

误食棘颚口线虫感染病例1例

目的对宁海县1例本地感染棘颚口线虫病例进行诊断和治疗。方法收集患者发病、临床表现、诊治过程等信息,对患者进行流行病学调查。采用镜检方法进行虫种鉴定。结果调查结果显示该患者误食野猪胃内活虫发病,虫体经胃镜取出后镜检全身有小棘,尾部及体后部的棘较细,形状如针,排列紧密。结论确认该患者为误食棘颚口线虫感染病例。     

刚刺颚口线虫对猪的致病性研究

猪颚口线虫病的临床症状是病猪经常呕吐、食欲减退、消瘦和体重减轻，早期血检嗜酸性细胞增高。本病的主要致病器官是胃和肝脏。胃的主要病变是胃底布满虫洞、粘膜增厚、发炎和溃疡。肝的病变是结缔组织增生、虫道出血、肝细胞索紊乱、肝细胞脂肪变性、萎缩和坏死。文中讨论了幼虫在体内的移行途径和本病的防治问题。     

Gnathostomiasis Acquired by British Tourists in Botswana

Infection with Gnathostoma spinigerum has been generally confined to Southeast Asia and Central and South America. However, gnathostomiasis was recently found in British tourists who had visited Botswana. Consequently, travel to Africa should now be considered a risk factor for gnathostomiasis.     

In vitro antiplasmodial activity of Central American medicinal plants

The in vitro antiplasmodial activities of 14 plant species traditionally used in Central America for the treatment of malaria or fever were evaluated. Lipophilic extracts of Piper hispidum, Siparuna andina, S. pauciflora, S. tonduziana, and Xylopia cf. frutescens, proved to be active against both a chloroquine-sensitive and a resistant strain of Plasmodium falciparum. IC50 values ranged between 3.0 microg/ml and 21.9 microg/ml; however, moderate cytotoxicity of active extracts was observed. Bioactivity-guided fractionation of Piper hispidum yielded 2',4, 6'-trihydroxy-4'-methoxydihydrochalcone (asebogenin) as an active compound.     

广东五华县棘颚口线虫的流行病学调查

目的 了解广东省五华县棘颚口线虫的流行情况。方法 从当地采集剑水蚤，经固定、沉淀分离、封片后，于显微镜下观察。从五华县县城菜市场购买鲩鱼、泥鳅、鳝鱼，其肌肉和肝脏经人工胃液消化后镜检。采用直接涂片法和饱和盐水浮聚法两种方法对从五华县转水镇采集的猫狗粪便进行检查。结果 剑水蚤棘颚口线虫第二期幼虫的感染率为1．6％；从34个鳝鱼肝脏样本中发现棘颚口线虫第3期幼虫2条；用饱和盐水浮聚法检查猫粪50份，2份找到棘颚口线虫卵。结论 五华县具备棘颚口线虫流行的基本条件。     

2014—2019年福建省市售淡水产品寄生虫感染情况调查

目的 了解福建省市售淡水产品寄生虫感染情况,为制定食源性寄生虫病的防控策略提供依据.方法 按照《福建省卫生健康委系统食品污染及有害因素监测方案》,采用分层整群随机抽样的方法进行抽样,将全省分为闽东、闽南、闽西、闽北和闽中5个地区,采集超市或农贸市场售卖的淡水鱼和淡水螺,采用消化法、压片法和剖检法检测寄生虫囊蚴或幼虫.结...     

Imported cutaneous gnathostomiasis: report of five cases

Gnathostomiasis has rarely been described outside endemic countries. We report on a series of 5 patients (4 females, 1 male, mean age 42.2 years) who returned to France from South-East Asia and presented with cutaneous gnathostomiasis. The cutaneous lesions appeared within a mean period of 62 d (range 10-150 d) after return. They consisted of creeping eruptions in 3 patients (in addition one also had papules, one had nodules and hepatitis, and one had hepatitis; all 3 had profound asthenia) and recurring migratory swellings in 2 patients. The mean eosinophil count was 1546/mm3 (range 398-3245/mm3). Diagnosis was based on positive serological tests in 3 patients and seroconversion in 2 patients, and was confirmed by identification of Gnathostoma hispidum in a biopsy specimen from one of the seropositive patients. Albandazole (1-4 courses) was given as treatment. Recurrences may occur up to 24 months after apparent cure without reinfection. Gnathostomiasis should be considered when patients return from tropical countries and present with migratory swellings or creeping eruption that does not respond to the usual treatment for cutaneous larva migrans. Serological tests may be negative initially and thus need to be repeated to check for seroconversion. Treatment may require multiple courses of albendazole and a prolonged period of follow-up is necessary before cure can be confirmed.     

Gnathostomiasis of the anterior chamber

Ocular involvement with Gnathostoma spinigerum occurs years after the initial infection that is acquired by ingestion of poorly cooked, pickled seafood or water contaminated with third stage larvae. Here we report a case of gnathostomiasis of the left eye of a 32-year-old lady hailing from Meghalaya, India. Her vision had deteriorated to hand movement. Slit lamp examination revealed a live, actively motile worm in the anterior chamber, which was extracted by supra temporal limbal incision and visual acuity was restored.