• The Microorganisms and Industry
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• v.13 no.3
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• pp.3-11
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• 1987

Hepatitis B virus (HBV) is a very serious threat to public health in most of the developing countries of the world. It is estimated that around 300 million people worldwide are chronic carriers of this virus and will transmit the disease both vertically and horizontally. Infection by this virus may cause a wide range of clinical manifestations ranging from an asymptomatic infection to liver cirrhosis.

• Korean Journal of Veterinary Research
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• v.63 no.1
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• pp.5.1-5.9
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• 2023

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, feline rehydragel-adjuvanted vaccine (FRAV) and feline cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.193-198
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• 1980

This paper deals with the studies on the occurence of a new virus disease of sesame and the identification of the causal virus. The virus disease of sesame has been regarded as a widespread disease in the sesame-growing areas in the southern part of Korea. The disease was found to be caused by watermelon mosaic virus (WMV). During the years since 1978, stunting of sesame plants, with yellow mosaic, necrotic spot, and malformation, were collected from 17 different places. Virus isolates from 27 out of 32 samples were identified as WMV. Natural infection of squash, pumpkin, cucumber, and watermelon by WMV as well as sesame was proved. The virus is inactivated at temperatures of 55 to $60^{\circ}C$, at dilution of $10^{-3}\;to\;10^{-4}$, and in the aging of 10 to 14 days at about $20^{\circ}C$. Sesame, Chenopodium amaranticelor, pea, bean, as well as many plants of the Cucurbitaceae, are susceptible to the sesame-isolates of WMV. In negatively stained preparations, particles of the virus appear under the electron microscope as flexible filaments of about $750\~800nm$ in length. Cylindrical inclusions and virus particles were found in the cytoplasm of mesophyll cells by ultra-thin sections of WMV infected tissues.

• Journal of Microbiology
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• v.44 no.2
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• pp.248-253
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• 2006

Lymphocystis disease virus (LCDV) is the causative agent of lymphocystis disease. The viruses have been divided into three genotypes (genotype I for LCDV-1, II for Japanese flounder isolates, and III for rockfish isolates) on the basis of major capsid protein (MCP) gene sequences. In this study, we developed a multiplex PCR primer set in order to distinguish these genotypes. We also analyzed the MCP gene of a new LCDV isolate from the sea bass (SB98Yosu). Comparison of sequence identities between SB98Yosu and eight Japanese flounder isolates, revealed identity of more than 90.1 % at nucleotide level and 96.5% at deduced amino acid level, respectively. Phylogenetic analyses based on the MCP gene showed that SB98Yosu belongs to genotype II, along with Japanese flounder isolates. Multiplex PCR based on the MCP gene allowed us to identify these genotypes in a simple and rapid manner, even in a sample that contained two genotypes, in this case genotypes II and III.

• Korean Journal of Veterinary Research
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• v.49 no.1
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• pp.39-44
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• 2009

Transmission of avian viruses both bird-to-bird and from birds to non-avian species is a major health concern. Newcastle disease virus (NDV) is an economically important avian virus that poses substantial risks to the poultry industry. Rapid and sensitive diagnostic methods, such as the enzymelinked immunosorbent assay (ELISA), are required to track such infections. To develop an ELISA for detecting anti-NDV antibody in avian sera, the nucleocapsid protein (NCP) gene of the NDV La Sota strain was cloned and expressed in Escherichia coli and the 513-amino acid recombinant NCP was purified by Ni-NTA affinity chromatography. To evaluate its ability to replace NDV whole virus antigen as a coating antigen, NCP-coated and whole NDV-coated ELISAs were tested and compared using a panel of NDV positive antisera from chickens. Results using purified NCP were highly correlated with those obtained using whole NDV (r= 0.927), demonstrating that recombinant NCP expressed in Escherichia coli is a suitable substitute antigen for whole NDV in a diagnostic ELISA.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.101-106
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• 1998

The present study attempted to apply polymerase chain reaction (PCR) to develop a rapid differential diagnosis among Marek's disease, reticuloendotheliosis and avian leukosis. The primers chosen to detect Marek's disease virus (MDV) flank the 132bp tandem direct repeat of the MDV genome. The primers selected for reticuloendotheliosis virus (REV) and avian leukosis virus (ALV) are based on proviral long terminal repeats of spleen necrosis virus and Rous-associated virus-2 genomes, respectively. The specific PCR products of MDV, REV and ALV were observed with each primer and the reaction was not cross-reacted among the viruses. MDV-specific DNA was also amplified from the MDV-induced lymphoma (MDCC-MSB1) but not from the REV-induced tumor and ALV-induced lymphoma (LSCC-1104B1). In addition, proviral DNA of REV from REV-induced tumor and proviral DNA of ALV from ALV-induced lymphoma were also amplified by REV-specific and ALV-specific PCRs, respectively. Therefore these three PCR methods may be used to rapidly differentiate among MDV, REV and ALV-associated tumors in diagnosis.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.57-61
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• 1992

To determin the accuracy of serological methods in detecting Borna-disease(BD) viral antibodies, 273 experimentally infected rabbit sera were compared by using indirect immunofluorescence antibody test(IFA), serum neutralization test(SN) and enzyme-linked immunosorbent assay(ELISA). One hundred twenty-three serum samples had BD viral antibodies detected by IFA. CELISA antibodies to BD virus were also present in the same one hundred twenty-three serum samples. However, neutralization test antibodies to BD virus were present in 27 of the in rabbit serum samples. Neutralization test was sensitive in comparison with KFA and CELISA. In comparison with IFA, CELISA was both sensitive and specific in detecting BD viral antibodies. These results extend observations made with laboratory animals to the diagnosis of naturally infected animals.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.125-130
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• 2013

Influenza viruses cause significant morbidity and mortality in humans through epidemics or pandemics. Currently, two classes of anti-influenza virus drugs, M2 ion-channel inhibitors (amantadin and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir), have been used for the treatment of the influenza virus infection. Since the resistance to these drugs has been reported, the development of a new antiviral agent is necessary. In this study, we examined the antiviral efficacy of the plant extracts against the influenza A/PR/8/34 infection. In vitro, the antiviral activities of the plant extracts were investigated using the cell-based screening. Three plant extracts, Thuja orientalis, Aster spathulifolius, and Pinus thunbergii, were shown to induce a high cell viability rate after the infection with the influenza A/PR/8/34 virus. The antiviral activity of the plant extracts also increased as a function of the concentration of the extracts and these extracts significantly reduced the visible cytopathic effect caused by virus infections. Furthermore, the treatment with T. orientalis was shown to have a stronger inhibitory effect than that with A. spathulifolius or P. thunbergii. These results may suggest that T. orientalis has anti-influenza A/PR/8/34 activity.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.249-252
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• 2017

Rabies virus (RABV) causes a neurological disease in warm-blooded animals that is nearly always fatal. In this study, we analyzed the matrix (M) genes in 10 Korean street RABV strains isolated from two Provinces during 2011-2013. The M genes in these 10 Korean strains were highly conserved during 1999-2013. Phylogenetic analysis revealed they were closely related to the M genes of RABVs isolated in northeastern China. Specific amino acid substitutions were identified in the KRVB1206, KRVF1301, and BV9901PJ strains. However, functional domains, including those involved in virus production and pathogenicity, were conserved in all 10 strains.

• Korean Journal of Veterinary Research
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• v.63 no.1
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• pp.1.1-1.4
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• 2023

Several outbreaks of Getah virus (GETV) have been reported in horses and pigs, causing large economic losses. However, there have been no reports describing serological survey for GETV in South Korea pigs. The present study conducted serological survey of GETV in South Korean pigs. A total of 670 whole blood samples were collected from domestic pigs. The overall seropositive rate was 26.4%, higher than the rates observed in racehorses in 2013-2014. Preparations for epidemics of novel diseases caused by climate change should include regular serological survey for these diseases, including GETV, and the development of vaccines against novel pathogens.