[鱼师]诺卡菌特异性PCR快速检测方法的建立

[鱼师]诺卡菌（Nocardia seriolae）是危害中国南方大口黑鲈（Micropterus salmoides）养殖业的主要病原之一,由于该菌在培养基上生长缓慢,对其分离鉴定造成诸多不便。文章根据[鱼师]诺卡菌16S-23S转录间隔区（ITS）序列设计特异性引物建立了[鱼师]诺卡菌特异性PCR快速检测方法。试验结果表明,利用设计的特异性PCR引物只能扩增出[鱼师]诺卡菌特异性片段,检出限为5pg模板DNA。在此基础上研制了PCR快速检测试剂盒并对[鱼师]诺卡菌人工感染的大口黑鲈组织进行了检测,结果显示该试剂盒能从未出现明显发病症状的大口黑鲈组织中检出阳性片段,阳性率为100％,比传统细菌分离鉴定方法更加灵敏、快速且高效,具有较好的应用前景。     

PCR检测对虾白斑综合征病毒(WSSV)中使用UNG防遗留污染

设计了一对引物用于PCR检测对虾白斑综合征病毒，PCR扩增过程中用尿嘧啶-DNA糖基酶(UNG)防遗留污染。使用UNG时，该对引物的适宜dUTP和Mg^2 浓度分别为0．4mmol／L和2．0mmol／L；UNG存在时，PCR检测WSSV DNA的最低量为1pg，UNG的使用使PCR的检测灵敏度降低了1个数量级；进行正常PCR扩增前，0．5U UNG可消除至少10ng含dU的WSSV DNA的PCR扩增产物。     

Biochemical characterization and physiological role of cortical rods in black tiger shrimp, Penaeus monodon

Cortical rods (CRs), precursors of egg jelly investment in many penaeoid shrimp, are composed of different proportions of proteins and carbohydrates, the physiological role of which still requires extensive investigation. In this study, we demonstrated the biochemical properties of the CRs and their role in the induction of the acrosome reaction (AR). Profiles of the isolated CRs revealed a number of major protein bands ranging from 35 to 230 kDa. These CR proteins were extensively glycosylated and sulfated. Lectin-based carbohydrate analysis further revealed the highest reactivity of concanavalin A (Con A) among other lectins used. In addition, the selective interference of Con A binding with mannose but not glucose indicated that CR glycoproteins were of high-mannose type. Using immunoblotting with anti-CR antibody, we further demonstrated that part of egg water (EW, a natural AR inducer) was derived from miscible components of the CRs. Physiological tests of water-soluble CR (wsCR) revealed its high AR inducing competency comparable to that of EW, which was far superior to that of acid-urea treated CR (auCR). Furthermore, the wsCR-induced AR was selectively inhibited by Con A, suggesting the significance of the exposing mannose residues in regulating P. monodon sperm AR response.     

西伯利亚鲟（Acipenser baeri）养殖群体遗传结构的AFLP分析

本研究构建了西伯利亚鲟（Acipenser baeri）扩增片段长度多态性（AFLP）分析体系,分析了DNA提取、双酶切反应、连接反应、预扩增反应、选择性扩增反应和银染等步骤。用7对引物对24尾西伯利亚鲟进行了AFLP分析,每对引物扩增的位点数在24～39之间,共扩增出了234个位点,多态性位点为116个,多态性比例为48.83%,平均Nei氏基因多样性指数H为0.4297,平均Shannon氏指数I为0.1233,个体间平均遗传距离为0.1872,表明西伯利亚鲟养殖群体的遗传多样性程度比较低,同时还构建了西伯利亚鲟的聚类图。     

重金属离子对鱼类血液指标影响的研究

此次试验的目的是研究鲤鱼经短时间高浓度的重金属溶液的暴露,几项血液学指标的变化情况。鲤鱼分别在铅、铜、镉、锌溶液中暴露3h后,随即转置于清洁水中,并立即随机抽取血液样本,以后隔天抽样,到第96h抽样后完成。结果发现:在红细胞系中,红细胞比容短暂升高,红细胞计数正常,红细胞体积发生临时膨胀,原红细胞比率增加。在白细胞系中,由于淋巴细胞数量的下降导致白细胞计数减少,嗜中性白细胞比率增加。结果表明:即使是在高浓度的重金属离子溶液中短时间的暴露,也会诱发鱼体的应激反应,机体加大能量的消耗来满足红细胞系的适应性变化,白细胞系内则出现了明显的免疫抑制反应,从而导致它们对疾病抵抗力的降低。     

DNA polymorphism in the growth hormone gene and its association with weight in olive flounder Paralichthys olivaceus

ABSTRACT: Variation within the growth hormone gene and its association with growth trait in the olive flounder ( Paralichthys olivaceus ) was investigated. Based on Southern blot analysis and using various kinds of restriction endonucleases, it was demonstrated that the growth hormone gene exists as a single copy gene in the olive flounder. Polymorphisms of various lengths were also detected by Southern blot analysis, and by the subsequent digestion of the polymerase chain reaction (PCR) -amplified growth hormone gene fragment with Sau 3AI restriction enzyme. To study the possible association between variation in the growth hormone and weight, 60 progenies of the hatchery strain of three various sizes (large, medium and small weight) were selected and the entire genetic structure of the growth hormone gene was analysed. A total of 15 different genotypes was observed from the random association of six haplotypes. Significant heterogeneity of the growth hormone gene with haplotype and genotype frequencies was detected among the different-sized groups.     

肝胰腺细小病毒和斑节对虾杆状病毒的PCR复合检测

肝胰腺细小病毒和斑节对虾杆状病毒是常见的2种DNA对虾病毒,在虾类养殖业中经常会出现混合感染。因此,建立这2种病毒的复合检测方法显得尤为重要。根据基因库中肝胰腺细小病毒和斑节对虾杆状病毒的保守序列,设计了肝胰腺细小病毒和斑节对虾杆状病毒的特异性引物,对这2种病毒PCR复合检测的反应条件和试剂浓度进行优化,退火温度55℃,主要试剂Mg2+终浓度为3mmol/L,dNTP终浓度为0.4 mmol/L,引物终浓度为0.8μmol/L。进一步比较了在优化后的PCR反应体系下,检测单种病毒和同时检测这2种病毒的灵敏度差异。     

氢化萜烯马来酸酐与环氧树脂固化反应特性研究

采用FT-IR光谱研究了氢化萜烯马来酸酐(HTMA)与双酚A型环氧树脂的固化反应过程,并分析了固化度、凝胶时间及其主要影响因素.实验结果表明:HTMA与环氧树脂的固化反应过程与促进剂作用下的酸酐固化环氧树脂的交联反应机理一致;固化度随温度升高、时间延长而提高,而凝胶时间随温度升高、促进剂用量的增加明显缩短.HTMA与双酚A型环氧树脂在110℃、8h以上可完全固化.空间位阻效应及电子效应的协同作用使HTMA与环氧树脂的固化反应速度降低,固化过程中放热量小,放热平缓.     

靛酚蓝反应测定氨氮的影响因素的探讨

针对靛酚蓝反应测定氨氮过程中存在的问题,提出了相应的解决方法,提高了试剂的稳定性,降低了空白吸光度。研究表明,影响该反应的主要因素为pH和试剂添加顺序。