水蛭AP神经元突触部位分辨的电导调控机制

用神经节－体壁标本，揭示ＡＰ神经元对邻节机构感受神经元传入信号也具有部位分辨机能。     

梳冬夜蛾和白边切夜蛾卵抗寒性研究

对梳冬夜蛾和白边切夜蛾卵的过冷却点、结冰点和不同低温强度及持续时间等指标的冷冻处理测定结果:梳冬夜蛾卵过冷却点为-18.76±4.09℃,结冰点为-17.7±5.02℃;白边切夜蛾卵的相应指标分别为-8.13±3.17℃和-7.15±3.09℃。两种蛾卵在一定的低温条件下,处理时间愈长,卵孵化率愈低;随着低温强度加大,卵孵化率明显降低。     

Multifunctional interneurons in behavioral circuits of the medicinal leech

Summary We are using the medicinal leech to study the neuronal basis of behavioral choice. In particular, we are recording from neurons, both extracellularly and intracellularly, in preparations that can express three different behaviors: the shortening reflex, crawling and swimming. We have found that particular mechanosensory neurons can elicit any of the behaviors, and that the movements are produced by just four sets of muscles, each controlled by a small number of motor neurons. Hence, there must be three different pattern-generating neuronal circuits, each of which can be activated by the same set of sensory neurons. We are studying how the choice is made among the three behaviors by recording, while one behavior is being performed, from neurons known to be involved in the initiation of the other two. We have found that an interneuron, cell 204, which is known to initiate and maintain swimming, is also active during shortening and crawling. The activity level in this interneuron can influence whether a mechanosensory stimulus produces shortening or swimming. The neuronal mechanisms by which this choice is normally effected awaits further elucidation of the circuits that elicit and generate shortening and crawling.     

几种水蛭抗凝血物质提取及活性分析

 研究3种提取方法对菲牛蛭不同处理品的抗凝作用,采用筛选的最佳提取方法分析了5种水蛭各处理品的抗凝血酶活性,并比较了3个不同地理分布野生菲牛蛭和2个不同饵料饲喂菲牛蛭各处理品的抗凝血酶活性。结果表明：丙酮浸提法在菲牛蛭各处理品中均具有最高的提取得率,所测抗凝血酶活性显著高于其他方法（P<0.05）;5种水蛭抗凝血酶活性测定结果显示非吸血蛭类的湿体匀浆液和干体无或微弱的抗凝活性,而吸血蛭类（日本医蛭和菲牛蛭）具有较高抗凝活性,且菲牛蛭的抗凝活性显著高于日本医蛭(P<0.01);不同地理分布野生菲牛蛭和不同饵料饲养菲牛蛭的湿体匀浆液、干体粉末和唾液腺分泌物抗凝活性均无显著差异（P>0.05）。研究表明菲牛蛭具有较强的体外抗凝血酶活性,且人工养殖对菲牛蛭的抗凝活性未产生不利影响。     

体外酶法水解制备小分子透明质酸

为了制备分子量分布集中的小分子透明质酸,在6g/L的高分子量透明质酸水溶液中加入一定梯度重组水蛭透明质酸酶,并控制水解时间。结果表明,通过控制加入重组水蛭HAase的量和水解时间,根据水解分子量下降规律,可以制备出分子量分布集中的小分子HA,包括水解终产物透明质酸四糖和六糖。同时,通过高效体积排阻色谱和琼脂糖凝胶电泳,可以证明水解产物的分子量分布集中。     

Synaptic connections between different sensory channels in CNS of the leech modulate the input of mechanosensory information

The mechanism for transmission of sensory information concerning a specific sensory modality or submodality can be called a sensory channel, including the receptors, sensory pathways and the parts of the central nervous system that further process the sensory information^[1,2]. A certain sensory channel can be activated by a suitable stimulus. Saraory infonnation is traduced by sensory receptor and is further transferred into central nervous system. The characteristics of a modality or submodality are meinly determined by the properties of the corresponding sensory receptors. However, besides the receptor properties, are there any other factors which have influence on the properties of a senwry modality? Is there a kind of gating mechanism existing which could selectively control the inputs of sensory information based on different sensory channels? Here we are trying to answer the above questions by studying the functional relationship between different mechanosensory modalities of leech.     

Improved geographic sampling provides further evidence for the separation of Glossiphonia complanata and Glossiphonia elegans (Annelida: Clitellata: Glossiphoniidae)

Historically, there has been much confusion surrounding the identity and separation of European and North American species of Glossiphonia (Annelida: Clitellata: Glossiphoniidae). Using cytochrome c oxidase subunit I (COI) sequences from newly collected specimens of Glossiphonia complanata and Glossiphonia elegans from a broad geographic range covering southern Canada, parts of the US, Slovenia and Croatia, we confirm that G. complanata is likely confined to Europe. The species is phylogenetically distinct from G. elegans, which seems to exclusively inhabit North America. Parsimony and maximum likelihood of the COI locus show the European samples placing as the sister group to an unidentified species of Glossiphonia from Russia, while the North American samples are the sister group to all other Glossiphonia species. We also investigate the consistency of number of crop cecae for separating these species and contrary to previous reports, this character shows no differences between our specimens of the two species. Additionally, the trees show evidence of subdivisions within both G. complanata and G. elegans, with some sequences separated by high ‘intraspecific’ distances. Forces might be shaping population structure and/or potential incipient speciation within these species, emphasizing the need for future research into the biogeography and population genetics of Glossiphonia.     

抗凝血药物水蛭素的纯化与鉴定

以湖南产日本医蛭嗉囊消化液作为原料，经三氯醋酸沉淀后用ＤＥＡＥ－纤维素柱层析一步纯化，反相ＨＰＬＣ脱盐后即可获得批量的水蛭素。对纯化的水蛭素进行了ＳＤＳ－聚丙烯酰胺凝胶电泳，质谱，Ｎ端顺序分析及抗凝血酶活性分析。     

水蛭养殖池塘生物组成与生长条件的研究

对人工养殖宽体金线蛭池塘的池水、浮游和底栖生物进行采样,分析池塘的水质、生物组成和数量,探究幼蛭培育、苗种投放和饲养的最优方法,并提出池塘的构建条件和养殖管理措施.结果表明:(1)水蛭养殖池塘的pH、含盐量和碱度均需符合水产养殖水质的标准;(2)在数量上,池塘中的浮游植物以蓝藻为主,浮游动物以原生动物为主,底栖动物以腹足类为主;(3)幼龄水蛭快速生长期为5~15 d;(4)2龄水蛭在收获期的体长达到投放初期体长的3倍,体重达到4倍以上;(5)设置泥土平台、水面种植水葫芦等措施可以促进水蛭生长.