Presence of Angiostrongylus cantonensis in Haiti

In the West Indies Angiostrongylus cantonensis was found first in Cuba in 1973, then in Puerto Rico (1986), in the Dominican Republic (1992) and recently in Jamaica (2002). Concurrently, the presence of the parasite was detected in the Bahamas and in New Orleans (LA, USA) in 1990. To assess the occurrence of A. cantonensis in Haiti, we investigated a number of rats in Port-au-Prince in 2002. Preliminary results among 23 captured and examined rats show that 75% (three of four) Rattus norvegicus and 21% (four of 19) R. rattus harboured A. cantonensis in their cardiopulmonary systems. Haiti is, for the first time, recognized as a new enzootic area for A. cantonensis in the Caribbean. This emerging zoonosis should be considered as a new public health hazard in Haiti.     

Chemo-paralysis for the removal of a live intraocular worm in ocular angiostrongyliasis

Angiostrongylus cantonensis is also called the rodent lung worm. It was first discovered in 1935 by Chen in Rattus rattus, in Canton, China. The rodent is the definitive host while infected mollusks, snails and crabs act as the intermediate hosts. Humans are infected by the 3rd stage larvae, either by eating undercooked intermediate hosts or by consuming vegetables.(1) It is a delicate nematode reported in Asia Pacific region most commonly in South-east Asia and has been reported from Taiwan, Thailand, Indonesia, Vietnam and Sri Lanka.(2) Anterior chamber angiostrogyliasis is extremely rare, and no previous case of ocular angiostrogyliasis from India could be found on Medline search. We report a new technique in the removal of the actively motile thread-like worm by paralysing it with intracameral preservative free lidocaine, which aids in the easy removal of the intact worm.     

THE CHRONIC AND SEVERE FORMS OF EOSINOPHILIC MENINGITIS

Two cases of chronic eosinophilic meningitis (presumed to be due to Angiostrongylus cantonen-sis) and a third patient with a severe form of this disease are described. Such cases are rare in the published literature. All patients developed their illness in Western Samoa, an area previously thought to be free of the disease. The need to consider eosinophilic meningitis in patients with chronic and severe neurological disease who live in, or have recently come from, endemic areas is emphasised.     

Stilbene and dihydrophenanthrene derivatives from <Emphasis Type="Italic">Pholidota chinensis</Emphasis> and their nitric oxide inhibitory and radical-scavenging activities

Two new stilbene derivatives, (E)-2′,3,3′-trihydroxy-5-methoxystilbene (1, Pholidotol C) and (Z)-3,3′-hydroxy-5-methoxystilbene (2, Pholidotol D), were isolated from the air-dried whole plant of Pholidota chinensis Lindl., together with eight known dihydrophenanthrene derivatives, lusianthridin (3), cannabidihydrophenanthrene (4), coelonin (5), hircinol (6), erianthridin (7), 4,5-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (8), eulophiol (9), and 2,4,7-trihydroxy-9,10-dihydrophenanthrene (10), and a benzoxepin derivative bulbophylol B (11). Their inhibitory effects on nitric oxide (NO) production activity and 1,1-diphenyl-2-picrylhydrazil radical-scavenging activity were examined. Among these compounds, 11 exhibited the most potent activity toward NO production inhibition activity and radical-scavenging activity; moreover, 11 reduced inducible nitric oxide synthase mRNA expression.     

广州管圆线虫一期幼虫的分离纯化及其抗原分析

目的建立广州管圆线虫一期幼虫的分离纯化方法,分析其抗原特性及血清学诊断价值。方法分别用贝尔曼漏斗法、蔗糖离心浮选法及改良贝尔曼法联合胰酶消化法从大鼠粪便中分离纯化一期幼虫;用SDS-PAGE和Western blotting进行蛋白谱与抗原谱分析;分别用一期幼虫和成虫抗原包被ELISA反应板,间接法检测不同样本中相应抗体。结果3种方法分离效率分别为50.1%、33.6%和19.7%;联合法获得的纯度最高,且90%以上的幼虫有活力;贝尔曼漏斗法分离的幼虫99%以上具有活力但纯度低;蔗糖离心浮选法分离的绝大多数虫体失去活力。一期幼虫104000Mr与广州管圆线虫感染2周的大鼠血清出现强反应,32000Mr和31000Mr与感染6周的大鼠血清、32000Mr与广州管圆线虫病患者血清均出现较强反应,与对照血清均未出现明显的反应;在ELISA检测中,一期幼虫抗原对广州管圆线虫病患者血清和感染大鼠血清的检出率与成虫抗原无统计学差异。结论改良贝尔曼法联合胰酶消化法可从大鼠的粪便中分离高纯度且具有活力的一期幼虫,一期幼虫104000Mr、32000Mr和31000Mr具有潜在的诊断价值,可望从大鼠粪便中分离一期幼虫开发诊断性抗原。     

细叶石仙桃的化学成分

目的：研究细叶石仙桃Pholidota cantonensis化学成分。方法：采用硅胶、Sephadex LH-20凝胶、Chromatorex ODS柱色谱法分离化合物，运用波谱学和理化方法鉴定结构。结果：分离得到4个化合物：pholidonone(1),ephemeranthoquinone(2),orchinol(3),batatasinⅢ(4)。结论：4个化合物均为首次从细叶石仙桃中分离得到，化合物1为新化合物。     

Upregulation of MMP-9/TIMP-1 enzymatic system in eosinophilic meningitis caused by Angiostrongylus cantonensis

Proteolysis depends on the balance between the proteases and their inhibitors. Matrix metalloproteinase-9 (MMP-9) and its specific inhibitors, tissue inhibitors of metalloproteinases (TIMP), contribute to eosinophilic inflammatory reaction in the subarachnoid space of the Angiostrongylus cantonensis-infected mice. The expression of MMP-9 in cerebrospinal fluid (CSF) was significantly increased in mice with eosinophilic meningitis, compared to that in uninfected ones. However, the TIMP-1 levels were unchanged and remained at basal levels at all time points, even in uninfected mice. Elevated MMP-9 mRNA expression coincided with protein levels and proteolytic activity, as demonstrated by means of positive immunoreactivity and gelatin zymography. CSF protein contents correlated significantly with MMP-9 intensity and CSF eosinophilia. In addition, immunohistochemistry demonstrated MMP-9 and TIMP-1 localization in eosinophils and macrophages. When the specific MMP inhibitor, GM6001, was added, MMP-9 enzyme activity was reduced by 45.4%. The percentage of eosinophil increased significantly upon the establishment of infection, but subsided upon inhibition. These results show that MMP-9/TIMP-1 imbalance in angiostrongyliasis may be associated with eosinophilic meningitis.     

三种淡水螺与广州管圆线虫相容性的实验研究

目的 比较福寿螺、中国圆田螺、铜锈环棱螺等3种食用淡水螺与广州管圆线虫的相容性。 方法 在相同条件下，用广州管圆线虫福建株感染3种螺，1、3、6、12及24 h后，随机抽样各20只，分别饲养于置有滤水器、水温（24±1）℃ 的玻璃缸内。记录感染2周内各组螺死亡数。第15天开始解剖，记录螺软体重量和感染虫数。同时设不感染螺对照组。 结果 3种螺感染后第1周死亡数达高峰。感染率和死亡率与螺的种类及感染时间均无相关性。虫负荷与虫密度，福寿螺感染6、12及24 h均显著高于感染1 h的（P值均<0.05）；铜锈环棱螺，感染24 h的均显著高于感染 1、3、6及12 h的（P值均<0.05）；中国圆田螺，感染1、3、6、12及24 h各组间差异均无显著性（P值均>0.05）。福寿螺感染6、12及24 h的虫负荷均显著高于铜锈环棱螺和中国圆田螺（P值均<0.05）。 感染6、12及24 h，福寿螺及铜锈环棱螺虫密度均高于中国圆田螺（P值均<0.05）。 结论 3种螺对广州管圆线虫均易感并有较高的相容性， 其中福寿螺的相容性较强。     

感染广州管圆线虫小鼠脑组织的病理变化观察

目的 观察小鼠感染广州管圆线虫后脑组织的病理学改变。 方法 以广州管圆线虫Ⅲ期幼虫人工感染BALB/c小鼠48只，每鼠经口感染40条幼虫，在感染后第7、10、13、16、19、22、25和28天分别解剖6只小鼠。取脑组织，切片后HE染色，观察脑组织病理改变，计数脑组织内虫体。各组均设平行对照健康小鼠1只。 结果 小鼠感染广州管圆线虫Ⅲ期幼虫后，第10 天肉眼下可从小鼠脑组织中检获虫体，但数量较少，平均为（7±1.73）条;感染后第16天，检获虫体最多，平均为（23.66±4.93）条；随后随感染时间的延长而逐渐减少。小鼠感染第15天时出现明显的神经系统症状，多数小鼠在感染后第22天死亡。病理切片观察可见脑组织有机械性损伤，脑实质中可见空洞及炎症反应。脑膜及蛛网膜下腔可见虫体，第13天即可见脑膜炎症反应，并随感染时间延长而加重。 结论 小鼠感染广州管圆线虫Ⅲ期幼虫可引起脑组织病理改变，并随感染时间延长逐步加重。     

血吸虫病肝纤维化小鼠IL-22表达及肝星状细胞衰老的意义

目的 目的 观察血吸虫病肝纤维化小鼠模型中白介素22 （IL?22） 及其受体 （IL?22R1） 的表达状况, 并对与IL?22相关的 肝星状细胞 （HSC） 衰老机制进行探讨。方法 方法 建立血吸虫病肝纤维化小鼠模型, 按感染后第4、 6、 8周及12周时间点取材, 行生化功能检测、 HE染色和Masson染色、 β?半乳糖苷酶染色检测HSC衰老状况、 ELISA检测肝组织中IL?22蛋白水平、 荧光 定量PCR检测肝组织中IL?22及IL?22R1mRNA表达水平, 另设未感染小鼠为对照组。结果 结果 感染后第8、 12周时血清中丙 氨酸氨基转移酶和天冬氨酸氨基转移酶水平较对照组明显增高 （P均＜0.05）。肝组织中IL?22蛋白于感染后第4、 6周时表 达较对照组明显增加 （P均＜0.05）, 感染后第8周时, 其表达水平较前下降, 第12周时仍维持在较低水平, 较第4、 6周差异 均有统计学意义 （P均＜0.01）。IL?22mRNA动态变化与蛋白水平一致, 感染后第4周时表达升高, 第6周时达高峰, 与对照 组比较差异均有统计学意义 （P均＜0.05）, 第8、 12周表达持续下降, 较第 6周差异均有统计学意义 （P均＜0.05）。IL? 22R1mRNA表达随病程进展逐渐升高, 于12周时达高峰, 较对照组、 第6周差异均有统计学意义 （P均＜0.05）。检测发现 HSC衰老, 随着IL?22在晚期病程中下降, HSC衰老减少。结论 结论 IL?22及其受体参与血吸虫病肝纤维化病程进展, 早期作 为炎症因子之一, 参与炎症反应; 至肝纤维化病程后期, 可部分通过诱导HSC衰老, 限制肝纤维化发展。