Dissertation > Excellent graduate degree dissertation topics show

A kind of aquatic the dual RNA virus isolation and clams cytopathology Change

Author: ShenHui
Tutor: XuZuo；YangJiaXin
School: Nanjing Normal University
Course: Aquaculture
Keywords: Meretrix meretrix Linnaeus Aqutic Birna-Like virus cytopathology purification artificial infection
CLC: S944.4
Type: Master's thesis
Year: 2007
Downloads: 57
Quote: 0
Read: Download Dissertation

Abstract


Since last decade, culture of the hard clam Meretrix meretrix Linnaeus is economically important industry in JiangSu province. Mass mortalities at clam farms which occur every summer and autumn, have caused serious losses to the industry. After we studied the epidemiology and histopathology, abundant spherical-shaped virus particles were found in the moribund hard clams.Electron microscopic examinations of ultrathin sections reveal the presence of spherical virus particles in the intercellular substance and cytoplasm of the gill, digestive diverticula, mantle, and digestive tract of the moribund hard clam Meretrix meretrix Linnaeus. And the virions are approximately 45 to 55 nm in diameter , having no envelope, no ambit between the core and nucleocapsid. In the infected cells with the virus, the cellular organelles presented obvious pathological changes: the endoplasmic reticulum swelled and mostly turn into vesicles, the nuclear chromatin condensed, the mitochondira swelled and dissolved , the muscle fiber was disarray, the number of lysosome arised , and so on.The virus was purified by differential centrifugation, potassium tartrate cushion ultracentrifugation, CsCl density gradient centrifugation. We also compared the sucrose, potassium tartrate-glycerol, CsCl density gradient ultracentrifugation, and the result showed that the CsCl density gradient ultracentrifugation is suitable for virus purification. With the negative staining, the virions are isometric symmetry, and approximately 60 to 75 nm in diameter. And there are many obvious capsomers on the surface of the virions. The virions having buoyant density of 1.554 to 1.582g/ml in the isopycnic CsCl gradient by the metage mothod.To ensure the virus systematic status, two step (RT)-PCR was used in the study. The first step is a reverse transcription (RT) using the M-MLV Rtase cDNA Kit (TaKaRa). The second step is PCR using two Primer (PrA and PrB) which reported by Blake (1995) for detection the aquatic Birnavirus. The results showed that PrA did not identify the 1180-bp fragment,but the PrB identified the 524bp fragment. So we suggested the spherical-shaped virus could be the Aquatic Birna-Like virus.The infetious virus, which was isolated from the moribund hard clam Meretrix meretrix Linnaeus in the outbreak area, were used to reinfect the cultured hard clam Meretrix meretrix Linnaeus. The artificial infection experimental results showed that the mortality of the hard clam both reached 100% after virus injection and virus soak. The mortality of the hard clam in the control was only 10%. Our preliminary suggestion is that the aquatic Birna-like virus could be the pathogen of the massive death.

Related Dissertations

  1. Study on Protective Effects of Apple Polyphenol on Immune System Injury Caused by γ-Ray,S661.1
  2. Study on Wastewater Purification Effect of the Free Surface Wetland with Different Substrates and Plant Combination,X703
  3. Studies on Fermentation Optimization, Purification and Enzyme Characteristics of Lipase from Aspergillus Oryzae FS-1,TQ925.6
  4. Studies on Isolation, Purification and Chemical Structure for Polysaccharides from Camellia Chrysantha(Hu) Tuyama,S567.19
  5. Purification of Endogenous Proteases from (Litopenaeus Vannamei) Shrimp Head and Their Enzymology Properties,S985.21
  6. Study on the Preparation of the Low Molecular Weight Fuciodan from Sargassum Henslowianum (C.Agardh) and Anti-tumor Activity,TS254.9
  7. Under microaerobic conditions closed calcium carbide furnace exhaust COS gas adsorption purification,X781
  8. Studies on Extraction and Analysis of Fructooligosaccharides in Smallanthus Sonchifolius,TS255.1
  9. Experiment Study of the Biogas Purification Process by Zeolite Filling Washing,TQ221.11
  10. Optimization of Fermentation Conditions, Purification, Cloning and Expression of a Cold-active Lipase from Pseudomonas Sp.RT-1,TQ925
  11. Extraction, Purification and Antifungal Activity of Anthocyanins in Drop Fruits of Chinese Baberry,TQ914.1
  12. Preliminary Research on Characterization of Thermophilic Protease Pasey and Helicase Htc16,Q814
  13. Study on the Separation and Purification Way of Arctiin from Fructus Arctii and the Effect of Arctiin on the Growth of Mice C2C12 Cells,S853.7
  14. Purification of Human Respiratory Syncytial Virus Fusion Protein with Immunomagnetic Microsphere Technology,R373
  15. Identification of Marine Sreptomyces Sp. GY-4 and Researches on Its Antimicrobial Substances,Q936
  16. Prokaryotic Expression and Purification of Human Beta-Defensin-9,Q78
  17. Study of Isolation and Identification on Antimicrobial Substances Produced by Lactobacillus Acidophilus NX2-6,TS201.3
  18. Study on Antioxidant Activities and Lipase-catalyzed Transesterification of Lard to Produce L-ascorbyl Fatty Acid Esters,TS202.3
  19. Isolation, Purification and Antioxidant Activity of Proteins from Chinese Yam,TS255.1
  20. Extraction of the Lipase from Pseudomonas Cepacia S31 and Its Applications in Food,TS201.25
  21. Study on Small Bank-based Constructed Wetland for Remediation of Polluted Water in City Stream,X703

CLC: > Agricultural Sciences > Aquaculture, fisheries > Fisheries Protection > Shellfish diseases, predators,and its control > A variety of sea shellfish diseases, predators,and its control
© 2012 www.DissertationTopic.Net  Mobile