国产河鲀毒素的生物效应

采用电压箝和膜片箝技术,观测河北河鲀毒素对神经和肌肉细胞的电生理效应,并与日本河鲀毒素进行比较.结果表明阻断钠电流的ED50的河北河鲀毒素浓度是3.68 nmol/L,对钠电流阻断的回复率为75%～92%;阻断钠电ED50的日本河鲀毒素浓度是4.1 nmol/L,对钠电流阻断的回复率为70%～80%.河北河鲀毒素比日本河鲀毒素的有效性和可逆性约高10%.     

海洋有毒甲藻Coolia monotis的研究概况

甲藻(Pyrrophyta)又称双鞭毛藻(Dinoflagellates),是海洋浮游植物的重要种群之一,其种类繁多,全世界已记录的约有130个属,1200个代表种。随着赤潮的频繁出现及赤潮毒素的强效活性的发现,有毒甲藻的危害及医药作用日益引起人们的重视。赤潮毒素是海洋生物活性物质中研究、开发进展最为迅速的领域之一。     

超声波提取-固相萃取联用检测河鲀毒素的研究

使用热处理、震摇、超声波等手段改善水产品中的河鲀毒素提取率,利用多种固相萃取柱纯化提取液,采用高效液相色谱-紫外检测法进行检测,重点对河鲀毒素的提取和固相萃取纯化进行了研究。试验发现,结合振荡和加热双重作用的索氏提取法和超声波加热辅助提取法具有较高的提取能力,其中超声波(35kHz,强度100%,60℃)提取10min即可达到最好效果,耗时短,效率更高;比较SCX、PRS、WCX、C18、SAX 5种固相萃取柱对河鲀毒素的吸附作用,SCX、PRS、WCX柱则能够将河鲀毒素完全保留在其上。样品纯化试验结果显示,C18-WCX小柱的组合纯化样品的效果最好,回收率在75%—82%之间,相对标准偏差小于15%。研究结果对河鲀毒素的提取、纯化和检测工作具有重要的参考意义。     

PROPERTIES OF PROTEOLYTIC TOXIN OF VIBRIO ANGUILLARUM FROM DISEASED FLOUNDER

Extracellular products(ECP)produced by Vibrio anguillarum strain M3 originally isolated from diseased flounder(Paralichthys olivaceus)were prepared.ECP of M3 showed gelatinase,casinase,amylase and haemolytic activity on agarose plates.High protease activity against azocasin was detected.Bacterium M3 showed highest growth and protease activity at 25℃。The Protease present in ECP showed maximal activity at pH 8 and 55℃；was completely inactivated by application of 80℃ heat for 30 min;was completely inhibited by EDTA and HgCl2,and was partially inhibited by PMSF,SDS,MnCl2 and iodoacetic acid;but not inhibited by CaCl2 and MgCl2.The ECP was toxic to flounder fish at LD50 values of 3.1 μg protein/g body weight.The addition of HgCl2 and application of heat at 50℃ decreased the lethal toxicity of ECP.When heated at 100℃,ECP lethality to flounder was completely in-hibited.After intramuscular injection of ECP into flounder,it showed evident histopathological changes including necrosis of muscle,extensive deposition of haemosiderin in the spleen,dilated bolld vessels congested with numerous lymphocytes in the liver.These results showed that ECP protease was a lethal factor produced by the baterium V.anguillarum M3.     

Production of monoclonal antibody and development of an enzyme-linked immunosorbent assay for the determination of okadaic acid in shellfish from China

An indirect competitive enzyme-linked immunosorbent assay（idc-ELISA） for quantitation of okadaic acid （OA） ,a marine biotoxin associated red tide, was developed by preparation of the monoclonal antibody against OA using cell-fused method.OA was coupled to KLH and OVA using carbodiimide reaction. OA-KLH used as immunogen were injected into Balb/C mice. Titres of the antisera against OA were determinated using OA-OVA as coating ligand by ELISA method. The spleen cells of immunized mice were fused with Sp2/O cells. Clones secreting specific monoclonal antibody were screened by indirect ELISA. After cloning, three hybridoma cell clones stably producing anti-OA monoclonal antibody were obtained. The detection of OA concentrations by indirect competitive ELISA was established. Under excellent condition, the detection limit of OA was 0.781 ng/mL. The level of OA in shellfishes from China was 0.001. A good correlation （R=0.7963） was observed between idc-ELISA and HPLC-MS/MS.     

两种蓝细菌中7对毒素-抗毒素系统的分析和鉴定

蓝细菌(cyanobacteria)是一类能进行放氧光合作用的原核生物。蓝细菌生长速度较快, 几乎存在于所有的陆地和水生环境中。毒素-抗毒素(toxin-antitoxin, TA)系统在原核生物中分布十分广泛, 在细菌的生命活动中扮演了重要的角色, 如维持水平基因转移元件的稳定性以及应对环境胁迫压力等。已有的基因组分析表明, 蓝细菌基因组中含有大量潜在的毒素-抗毒素系统, 但是目前对蓝细菌毒素-抗毒素系统的实验鉴定仍较少。本文分别以淡水和海水代表菌株集胞藻PCC6803(Synechocystis sp. PCC6803)和聚球藻WH7803(Synechococcus sp. WH7803)为研究对象, 对二者基因组上的毒素-抗毒素系统进行预测, 并选取预测结果中的7对潜在的毒素-抗毒素系统进行实验验证。结果表明, 集胞藻PCC6803的两对毒素-抗毒素系统BAD01932-1933 和 BAA18559-New ORF7中的毒素具有明显的细胞毒性。本文的研究结果有助于后续对蓝细菌毒素-抗毒素系统及其生态和生物学功能的研究。     

A型肉毒毒素与针刺联合上肢智能训练系统对脑梗死患者上肢功能的影响

目的：探讨A型肉毒毒素与针刺联合上肢智能训练系统对脑梗死患者上肢运动功能的影响。方法：将脑梗死患者60 例按随机数字表分为治疗组和对照1、2组,每组各20 例。对照1组采用常规基础康复治疗,对照2组在对照1组的基础上采用注射A型肉毒毒素及针刺治疗,治疗组在对照2组的基础上辅以上肢智能训练系统训练。采用美国国立卫生研究院卒中量表（NIHSS）、Fugl-Meyer上肢运动功能评定量表（FMA）、改良Ashworth评分及肩关节前屈主动活动度评分比较3组治疗效果。结果：治疗后,3组NIHSS、FMA、改良Ashworth评分及肩关节前屈主动活动度评分较治疗前均有改善,且治疗组改善程度优于对照1、2组,对照2组又优于对照1组,差异均有统计学意义（P<0.05或P<0.01）。结论：在A型肉毒毒素注射和针刺治疗的基础上辅以上肢智能训练可更显著地改善脑梗死患者的上肢运动功能。     

Isolation and identification of a marine killer yeast strain YF07b and cloning of the gene encoding killer toxin from the yeast

It was found that the marine yeast strain YF07b could secrete a large amount of killer toxin against a pathogenic yeast strain WCY which could cause milky disease in Portunus trituberculatus.The marine yeast strain YF07b was identified to be Pichia anomala according to the results of routine yeast identification and 18S rDNA and ITS sequences.The gene encoding killer toxin in the marine yeast strain YF07b was amplified by PCR technology.After sequencing,the results show that an open reading frame,consisting of 1 281 bp,encoded a presumed protein of 427 amino acids.The sequence of the cloned gene was found to have 99% match with that of the gene encoding killer toxin in Pichia anomalas strain K.A signal peptide including 17 amino acids appeared in the N-terminal domain of the killer toxin.Therefore,the mature protein consisted of 410 amino acids,its molecular mass was estimated to be 47.4 ku and its isoelctronic point was 4.5.     

蒙脱石对黄曲霉毒素B1的吸附作用

试验研究了蒙脱石对黄曲霉毒素B1的等温吸附，以及赖氨酸、酸碱度、温度、离体肠管吸收和透析袋透析对其吸附的影响。结果表明：蒙脱石在pH2．0和pH8．0时对黄曲霉毒索B1的最大吸附量分别为613．5和628．9μg/g；赖氨酸含量为2～4mg／mL时对吸附无影响；酸碱度在pH2．0至pH8．0及温度在20℃至60℃时对吸附无明显影响；蒙脱石可减少离体肠管对黄曲霉毒素B1的吸收率及黄曲霉毒素B1通过透析袋的透析率。鸡小肠对黄曲霉毒素B1存在主动吸收过程。在吸附反应的初始阶段，蒙脱石对黄曲霉毒素B1的吸附符合一级吸附动力学方程，黄曲霉毒素B1半衰期为6．3～7．3min；20min后达到吸附平衡。