• Title/Summary/Keyword: viral

Search Result 2,768, Processing Time 0.03 seconds

Microbial Control of the Tobacco Cutworm, Spodoptera litura (Fab.), Using S. litura Nuclear Polyhedrosis Virus. III. Field Evaluation of the Viral Insecticides (곤충 핵다각체병바이러스를 이용한 담배거세미나방의 생물적 방제. III. 담배거세미나방 핵다각체병바이러스 살충제 살포효과)

  • 임대준;진병래;최귀문;강석권
    • Korean journal of applied entomology
    • /
    • v.29 no.4
    • /
    • pp.252-256
    • /
    • 1990
  • Viral insecticides were formulated with Spodoptera litura nuclear polyhedrosis virus and different U.V. protectants based on white carbon, molasses, and white carbon and molasses mixture to use as microbial control agents. Effect of rainfall on the attachment of formulated viruses to leaves was no different between the treated and the non-treated experiment. Persistence of the formulations was lated 5 days on the surface-sprayed leaves and 12 days on the under-sprayed leaves which was showing 60% mortality. Total mortality of the viral insecticides was more than 97% with no differences among them. Field evaluation of three viral insecticides in soybean field was very successful then carried out in Chinju, a southern part of Korea. Mortality by the formulation in the field during 14 days was more than 93%, but the formulations contained molasses showed phytotoxicity on soybean leaves. Spray effect of the viral insecticides was begun to appear from 7 days later than that of chemical insecticide.

  • PDF

Identification of Viral RNA by Light Microscopic in situ Hybridization (광학현미경 In Situ Hybridization에 의한 Viral RNA 증명)

  • 최원기;주경웅;김석홍
    • Biomedical Science Letters
    • /
    • v.2 no.2
    • /
    • pp.249-255
    • /
    • 1996
  • In this paper, a in situ hybridization(ISH) has been used to investigate the yield of viral RNA expression from each organ tissues. It is studied to establish a rapidly, specific diagnostic method detecting rabbit haemorrhagic disease virus(RHDV) RNA in 10% formalin-fixed, paraffin-em-bedded tissues of naturally RHDV-infected rabbits using oligonucleotide probe to be made by RHDV total sequences. Biotin was used as the oligonucleotide probe marker. in situ hybridization is detected the virus genome in the cells and tissue as specifically compared with others nucleic acid hybridization method. All ISH procedure of RHDV were completed to Mi-croProbe$^{TM}$ capillary action system within 1-2 hours. In this report, RHDV was distributed widely in the cytoplasm of liver cell and the cortex of kidney but lung tissue and medulla of kidney were showed to positive reaction at locally. Although not entirely free of technical limitations, nucleic acid identification holds advantages over other diagnostic tests, including exquisite sensitivity, specificity, interchangeability and speed. It is expected that, in the immediate future viral nucleic acid detection will be a prominent part of the methods used in histopathology.

  • PDF

Virus-induced Silencing of the WRKY1 Transcription Factor that Interacts with the SL1 Structure of Potato virus X Leads to Higher Viral RNA Accumulation and Severe Necrotic Symptoms

  • Park, Sang-Ho;Kim, Kook-Hyung
    • The Plant Pathology Journal
    • /
    • v.28 no.1
    • /
    • pp.40-48
    • /
    • 2012
  • $Potato$ $virus$ $X$ (PVX) replication is precisely regulated by regulatory viral sequences and by viral and/or host proteins. In a previous study, we identified a 54-kDa cellular tobacco protein that bound to a region within the first 46 nucleotides (nt) of the 5' non-translated region (NTR) of the viral genome. Optimal binding was dependent upon the presence of an ACCA sequence at nt 10-13. To identify host factors that bind to 5' NTR elements including AC-rich sequences as well as stemloop 1 (SL1), we used northwestern blotting and matrixassisted laser desorption/ionization time-of-flight mass spectrometry for peptide mass fingerprinting. We screened several host factors that might affect PVX replication and selected a candidate protein, $Nicotiana$ $tabacum$ WRKY transcription factor 1 (NtWRKY1). We used a $Tobacco$ $rattle$ $virus$ (TRV)-based virus-induced gene silencing (VIGS) system to investigate the role of NtWRKY1 in PVX replication. Silencing of $WRKY1$ in $Nicotiana$ $benthamiana$ caused lethal apical necrosis and allowed an increase in PVX RNA accumulation. This result could reflect the balancing of PVX accumulation in a systemic $N.$ $benthamiana$ host to maintain PVX survival and still produce a suitable appearance of mosaic and mottle symptoms. Our results suggest that PVX may recruit the WRKY transcription factor, which binds to the 5' NTR of viral genomic RNA and acts as a key regulator of viral infection.

Analysis of the Three Dimensional Structure of Envelope Protein of the Japanes encephalitis virus Isolated in Korea (국내에서 분리된 일본뇌염 바이러스의 Envelope Protein의 3차구조 분석)

  • Nam, Jae-Hwan;Chae, Soo-Lim;Kim, Eung-Jung;Yoon, Kyung-Sik;Lee, Ho-Dong;Koh, Hyun-Chul;Cho, Hae-Wol
    • The Journal of Korean Society of Virology
    • /
    • v.27 no.2
    • /
    • pp.209-216
    • /
    • 1997
  • Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NlH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.

  • PDF

Association of Viral Infections with Risk of Human Lymphomas, Egypt

  • Kadry, Dalia Y;Khorshed, Amira M;Rashed, Reham A;Mokhtar, Nadia M
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.4
    • /
    • pp.1705-1712
    • /
    • 2016
  • Background: The aim of this study was to determine and evaluate the association of different viral infections, with hepatitis B and C viruses, Epstein-Barr virus, cytomegalovirus and human herpes virus-8 (HBV, HCV, EBV, CMV, HHV-8) with the risk of lymphomas (Hodgkin and non-Hodgkin) among Egyptian patients, and correlate with the histopathological staging and typing as well as the prevalence of combined infections. Materials and Methods: A total of 100 newly diagnosed lymphoma patients with 100 healthy age and sex matched normal controls were assayed for viral infection using enzyme linked immunosorbant assay (ELISA) followed by real time polymerase chain reaction (RT-PCR). Results: Our results showed a high statistical significant difference between cases and controls as regards clinical and laboratory findings (P<0.001 and=0.003). A high statistical difference was seen for the association of most viruses and lymphoma cases (p<0.001) except for positive HBs Ag, positive CMV IgG and HHV-8 (p=0.37, 0.70 and 1.0 respectively). No statistical significant difference was found between Hodgkin (HL) and non-Hodgkin (NHL) as regards viral prevalence except HCV antigen, 57.1% for HL and 26.5% for NHL (p = 0.03). Only, HBV DNA showed a high significant value among infiltrated bone marrow cases (p=0.003) and finally, a high significant association of 2 combined viral infections with infiltrated bone marrow lymphoma cases (p=0.04). Conclusions: Our results showed that infection with HBV, HCV, CMV and EBV were associated with increased risk of lymphoma among the Egyptian population. Detection of new associations between infectious agents and risk of cancer development will facilitate progress in elaboration of prophylactic measures, early diagnostic methods and, hopefully, novel therapy of malignant tumours.

Multi-resistance strategy for viral diseases and in vitro short hairpin RNA verification method in pigs

  • Oh, Jong-nam;Choi, Kwang-hwan;Lee, Chang-kyu
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.4
    • /
    • pp.489-498
    • /
    • 2018
  • Objective: Foot and mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are major diseases that interrupt porcine production. Because they are viral diseases, vaccinations are of only limited effectiveness in preventing outbreaks. To establish an alternative multi-resistant strategy against FMD virus (FMDV) and PRRS virus (PRRSV), the present study introduced two genetic modification techniques to porcine cells. Methods: First, cluster of differentiation 163 (CD163), the PRRSV viral receptor, was edited with the clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 technique. The CD163 gene sequences of edited cells and control cells differed. Second, short hairpin RNA (shRNAs) were integrated into the cells. The shRNAs, targeting the 3D gene of FMDV and the open reading frame 7 (ORF7) gene of PRRSV, were transferred into fibroblasts. We also developed an in vitro shRNA verification method with a target gene expression vector. Results: shRNA activity was confirmed in vitro with vectors that expressed the 3D and ORF7 genes in the cells. Cells containing shRNAs showed lower transcript levels than cells with only the expression vectors. The shRNAs were integrated into CD163-edited cells to combine the two techniques, and the viral genes were suppressed in these cells. Conclusion: We established a multi-resistant strategy against viral diseases and an in vitro shRNA verification method.

Prevalence of viral nervous necrosis (VNN) in sevenband grouper Epinephelus septemfasciatus farms (능성어 양식장에서의 viral nervous necrosis (VNN) 발생양상)

  • Kim, Choon-Sup;Kim, Wi-Sik;Nishizawa, Toyohiko;Oh, Myung-Joo
    • Journal of fish pathology
    • /
    • v.25 no.2
    • /
    • pp.111-116
    • /
    • 2012
  • Prevalence of viral nervous necrosis (VNN) in sevenband grouper Epinephelus septemfasciatus farms was investigated during the period of 2006-2008. The outbreak of the VNN was observed from August (water temperature: $24-26^{\circ}C$) to September or October ($20-25^{\circ}C$). The viral infection resulted in acute or chronic mortality of the host, where the mortality rate of juvenile fish was higher than that of the adult fish. Phylogenetic analysis based on partial RNA2 coat protein gene nucleotide sequences revealed that all the isolates from sevenband grouper were classified into the genotype redspotted grouper nervous necrosis virus (RGNNV). In conclusion, VNN of juvenile and adult sevenband groupers during the summer season (July to October, water temperature: about $24^{\circ}C$) was caused by virus belonging to the genotype RGNNV.

Screening of Anti-HIV-1 Activity of Natural Products by MTT Assay (MTT Assay에 의한 천연물질의 항 HIV-1 활성 검색)

  • Lee, Joo-Shil;Nam, Jeong-Gu;Kang, Chon;Lee, Hong-Rae;Lee, Young-Jong;Shin, Yung-Oh
    • The Journal of Korean Society of Virology
    • /
    • v.27 no.1
    • /
    • pp.87-95
    • /
    • 1997
  • Methanol and/or boiling water extraction of 201 natural products and subsequent MTT assay using MT-4 cell line was carried out to screen the anti-HIV-1 activity. Among 97 methanol extracts, 7 extracts from Chrysanthemi Indicium Flos, Magnoliae Cortex, Machili Cortex, Reynoutriae Rhizoma, Lithospermi Radix, Agastachis Herba, and Chaenomelis Fructus showed anti-HIV-1 activity and their SI value were 2.25 to 5.77. In addition, among 119 boiling water extracts, 10 extracts from Lonicerae Caulis et Foloium, Elsholtziae Herba, Leonuri Herba, Portulacae Herba, Schizonepetae Herba, Curcumae Rhizoma, Amomi Cardamomi Fructus, Cirsii Radix et Herba, Carpesii Herba, and Siegesbeckiae Herba showed anti-HIV-1 activity and their SI value were 1.30 to 7.64. Methanol extracts of above seven natural products were fractionated and the anti-HIV-1 activity of each fraction was examined. Extraction was carried out with hexane, chloroform, butanol, and water to trace active anti-HIV-1 componets. As a result, the water fraction of Magnoliae Cortex, Machili Cortex, Reynoutriae Rhizoma, Agastachis Herba, Chaenomelis Fructus and the butanol fraction of Chrysanthemi Indicium Flos, Reynoutriae Rhizoma showed anti-HIV-1 activity and their SI value were 1.40 to 8.02. We could reach a conclusion that studies to trace the anti-HIV-1 active component of each natural products in further fractionation and to identify its structure by Infrared spectroscopy, NMR spectroscopy and gel permeation chromatography were needed.

  • PDF

An Outbreak of Viral Haemorrhagic Pneumonia(Tentative Name) of Rabbits in Korea (토끼의 바이러스성 출혈성 폐렴(잠정명칭) 발생)

  • Park Nam-Yong;Chong Chi-young;Kim Jin-ho;Cho Sung-man;Cha Yeon-ho;Jung Byung-tack;Kim Dong-sung;Yoon Ji-byung;Park Jin-yul;Wee Sung-ha
    • Journal of the korean veterinary medical association
    • /
    • v.23 no.9
    • /
    • pp.603-610
    • /
    • 1987
  • The pathological and microbiological studies were carried out to investigate an acute, febrile, highly fetal, infectious disease of rabbits that had occurred in the Winter and in the Spring and that had begun to be reported in Korea from November, 1985. The clinical signs of this disease were characterized by high fever, lethargy, piercing shriek, convulsion, and sudden death with epistaxis, but often they were not observed. The predominant pathogical findings were severe congestion and hamorrhage in trachea, dark brown discoloration of liver by diffuse necrosis or acute viral hepatitis, and hamorrhagic damages of lung, heart, spleen, kidney, etc. The etiological agent was a small round virus, in 25-35nm in diameter and without envelope, thus looking like a picorna virus. This disease resembled what was called the 'Viral Hamorrhagic Pneumonia in Rabbits'(tentative name) that had been reported for the first time in China in 1984. It will be desirable that the disease should be renamed as the 'Viral Hemorrhagic Fever in Rabbits', the 'Acute Viral Hepatitis in Rabbits', etc. because of its charateristics and the basis of pathological findings. An inactivated vaccine is now in the process of preparation for the prophylaxis of this viral disease.

  • PDF

High Efficiency Retroviral Vectors with Improved Safety

  • Yu, Seung-Shin;Kim, Jong-Mook;Kim, Sun-Young
    • Proceedings of the Korean Society for Applied Microbiology Conference
    • /
    • 2000.10a
    • /
    • pp.31-50
    • /
    • 2000
  • Almost all currently available retroviral vectors based on murine leukemia virus (MLV) contain one or more viral coding sequences Because these sequences are also present in the packaging genome, it has been suggested that homologous recombination may occur between the same nucleotide sequence in the packaging genome and the vector, resulting in the production of replication competent retrovirus (RCR). Up until now, it has been difficult to completely remove viral coding sequences since some were thought to be involved in the optimum function of the retroviral vector. For example, the gag coding sequence present in almost all available retroviral vectors has been believed to be necessary for efficient viral packaging, while the pol coding sequence present in the highly efficient vector MFG has been thought to be involved in achieving the high levels of gene e(pression. However, we have now developed a series of reroviral vectors that are absent of any retroviral coding sequences but produce even higher levels of gene expression without compromising viral titer. In these vectors the intron and exon sequences from heterologous cellular or viral genes are present, When compared to the well blown MLV-based vectors, some of these newly developed vectors have been shown to produce significantly higher levels of gene expression for a longer period. In an experimental system that can maximize the production of RCR, our newly constructed vectors produced an absence of RCR. These vectors should prove to be safer than other currently available retroviral vectors containing one or more viral coding sequences

  • PDF