• Korean Journal of Poultry Science
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• v.32 no.2
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• pp.113-123
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• 2005

Avian influenza (AI) virus (AIV) is distributed worldwide and it has been isolated from various species of wild and domestic birds. AI transfers with high speed and shows diverse pathogenicity syndroms. In Korea, several low Pathogenic AIV, H9N2, have been isolated from the commercial farms with severe decrease of egg production and mortality resulted in severe economic loss since 1996. Therefore, it has been requested to develop AI vaccines to prevent clinical signs and economic losses from the field infection of AIV. To develop a killed vaccine that efficiently prevents low pathogenic AIV (H9N2), evaluation on the pathogenicity and selection of an inactivator for H9N2 is taking place and is being tested safety and immunogenicity of vaccine produced. Based on the pathogenicity test and viral reisolation test, the ADL0401 isolate is the characteristic low pathogenic AIVs and has fairly similar biologic functions compared with MS96 which is the official low pathogenic AIV (H9N2) and one of the predominant AIV isolated from poultry farms in Korea. In antigenicity tests, the ADL0401 and MS96 virus have no significant antigenic difference. In inactivation tests, the ADL0401 isolates can be easily inactivated with $0.1\%$ Formalin at $37^{\circ}C$ within 1 hour with a little decrease of HA titer. The vaccine developed in the present report has no harmful effect on bird and forms good immune capability. Therefore, the isolates, ADL0401 can be used for a killed vaccine which can reduce the clinical signs and viral shedding in the birds infected with H9N2 low pathogenic AIVs.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.67.2-67
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• 2000

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.20-25
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• 2008

The susceptibility of five different marine fish to iridovirus IVS-1 infection was analyzed and found a higher the cumulative mortality in the order of rock bream (Oplegnathus fasciatus), red sea bream (Pagrus major), sea perch (Lateolabrax sp.), rockfish (Sebastes schlegeli) and black porgy (Acanthopagrus schlegeli). However, the concentrations of virus in the infected spleens of these species did not differ significantly. To determine the release of iridovirus from infected fish into culturing seawater, rock bream were challenged with iridovirus IVS-1 and the concentration of virus in the water was analyzed using PCR. Over the 10 days of the analysis, the linear relationship between the number of dead fish and viral DNA concentration found in culturing seawater should be considered direct evidence of horizontal iridovirus transmission.

• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.121-128
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• 2017

Protozoan viruses may influence the function and pathogenicity of the protozoa. Trichomonas vaginalis is a parasitic protozoan that could contain a double stranded RNA (dsRNA) virus, T. vaginalis virus (TVV). However, there are few reports on the properties of the virus. To further determine variations in protein expression of T. vaginalis, we detected 2 strains of T. vaginalis; the virus-infected ($V^+$) and uninfected ($V^-$) isolates to examine differentially expressed proteins upon TVV infection. Using a stable isotope N-terminal labeling strategy (iTRAQ) on soluble fractions to analyze proteomes, we identified 293 proteins, of which 50 were altered in $V^+$ compared with $V^-$ isolates. The results showed that the expression of 29 proteins was increased, and 21 proteins decreased in $V^+$ isolates. These differentially expressed proteins can be classified into 4 categories: ribosomal proteins, metabolic enzymes, heat shock proteins, and putative uncharacterized proteins. Quantitative PCR was used to detect 4 metabolic processes proteins: glycogen phosphorylase, malate dehydrogenase, triosephosphate isomerase, and glucose-6-phosphate isomerase, which were differentially expressed in $V^+$ and $V^-$ isolates. Our findings suggest that mRNA levels of these genes were consistent with protein expression levels. This study was the first which analyzed protein expression variations upon TVV infection. These observations will provide a basis for future studies concerning the possible roles of these proteins in host-parasite interactions.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.207-213
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• 2009

Rabbit hemorrhagic disease (RHD) is caused by RHD virus (RHDV) and is one of the most fatal diseases of rabbits. Acute death of rabbits occurred in a farm located in the Gyeonggi province of South Korea. The virus was isolated and confirmed as RHDV based on reverse transcription polymerase chain reaction and hemagglutination assay (HA), and the isolate was designated as KV0801. The nucleotide sequence of the complete VP60 gene of KV0801 was determined and the corresponding amino acid sequence was deduced. Molecular analysis showed that the KV0801 isolate can be classified as a pandemic antigenic variant strain, RHDVa. The VP60 nucleotide sequence and deduced amino acid homology between KV0801 and other Korean isolate, RHF89, which was isolated in 1988, were 92.1 and 94.3%, respectively. The pathogenicity of the KV0801 isolate at an HA titer ranging from 16,384 to 0.16 HA units was evaluated in five-month-old SFP rabbits. The rabbits inoculated with KV0801 isolate containing more than 1.63 HA units died within six days of inoculation. These results suggest that a highly pathogenic RHDVa is circulating in the rabbit populations of Korea.

• Genomics & Informatics
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• v.18 no.1
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• pp.5.1-5.5
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• 2020

Highly pathogenic avian influenza (HPAI) viruses have caused severe respiratory disease and death in poultry and human beings. Although most of the avian influenza viruses (AIVs) are of low pathogenicity and cause mild infections in birds, some subtypes including hemagglutinin H5 and H7 subtype cause HPAI. Therefore, sensitive and accurate subtyping of AIV is important to prepare and prevent for the spread of HPAI. Next-generation sequencing (NGS) can analyze the full-length sequence information of entire AIV genome at once, so this technology is becoming a more common in detecting AIVs and predicting subtypes. However, an analysis pipeline of NGS-based AIV sequencing data, including AIV subtyping, has not yet been established. Here, in order to support the pre-processing of NGS data and its interpretation, we developed a user-friendly tool, named prediction of avian influenza virus subtype (PAIVS). PAIVS has multiple functions that support the pre-processing of NGS data, reference-guided AIV subtyping, de novo assembly, variant calling and identifying the closest full-length sequences by BLAST, and provide the graphical summary to the end users.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.26-37
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• 2009

Tomato spotted wilt virus (TSWV) was identified from seven plants at two areas, Anyang and Dangjin, in Korea. The isolates of TSWV were seven as TSWV-KATm from tomato, TSWV-KAPo from potato, TSWV-KABal from balsam, TSWV-KACTm from cherry tomato and TSWV-KAIxe from Ixeris dentata at Anyang area, and TSWV-KDSe from sesame and TSWV-KDRP from red pepper at Dangjin area. Pathogenicity of seven TSWV isolates was various on the assay plants, and could not be grouped definitely. Three isolates of TSWV-KAIxe, TSWV-KACTm and TSWV-KABal had relatively narrower host ranges among the seven isolates. Percentage of nucleotide substitution in nucleotide sequences encoding nucleocapsid protein (NCP) was 1.2-1.7% among seven TSWV isolates and TSWV-KP. Korean TSWV isolates were divided into three groups by nucleotide homology or amino acid compositions. From the analysis of nucleotide sequences of Korean TSWV isolates compared with those of TSWV reported from other 5 countries including Japan, the Korean seven isolates of TSWV was grouped with German TSWV (D13926). No Korean TSWV isolates were grouped with those from The Netherlands, Brazil and USA.

• Korean Journal of Veterinary Research
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• v.52 no.1
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• pp.9-18
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• 2012

Rabies is a major zoonotic disease that causes approximately 55,000 human deaths worldwide on an annual basis. The nucleocapsid protein and glycoprotein genes of the Korean rabies virus (RABV) have been subjected to molecular and phylogenetic analyses. Although the phosphoprotein (P) has several important functions in viral infection and pathogenicity, the genetic characterizations of the P of Korean RABV isolates have not yet been established. In the present study, we conducted genetic analyses of P genes of 24 RABV isolates circulating in the Republic of Korea (hereafter, Korea) from 2008 to 2011. This study revealed that the P genes of Korean RABVs are genetically similar to those of RABV strains of lyssavirus genotype I including V739 (dogs, Korea), NNV-RAB-H (humans, India), NeiMeng925 (raccoon dogs, China), and RU9.RD (raccoon dogs, Russia). Among Korean isolates, the RABV P genes showed low variability in the variable domains among Korean isolates; they had specific consensus sequences and amino acid substitutions capable of identifying geographic characteristics and retained specific sequences thought to be important for viral function. These results provide important genetic characteristics and epidemiological information pertaining to the P gene of the Korean RABV.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.349-359
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• 1994

To elucidate pathogenicity to hamster of encephalomyocarditis virus $K_3$ strain that was isolated in Korea from the swine with reproductive failures, adult male syrian hamsters were experimentally infected intraperitoneally with the virus at $10^{7.0}\;TCID_{50}/0.1ml$ and pathological and immunohistochemical studies were performed. The results obtained through the experiment were as follows. 1. Clinical signs such as depression, unkempt hair and bilateral parlysis of hind limbs were observed. 2. At necropsy, mild congestion was observed in the cerebrum, liver, kidney and lung, and atrophy was evident in testis. 3. In microscopic observation, degeneration and necrosis of the nervous cells and perivascular mononuclear cell infiltration were manifested in central nerve system, and various degrees of degeneration and necrosis of parenchymal cells were detected in pancreas, lacrimal gland, liver, kidney and testis. 4. In immunohistochemical observation, strong positive reactions were observed in degenerated parenchymal cell of testis, and weak positive reactions, in hepatocytes.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.68-68
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• 2022

The pepper mild mottle virus (PMMoV), belonging to the tobamovirus genus, is currently one of the most destructive pathogens in pepper production. Tobamoviruses have been classified in terms of increased pathogenicity as pathotypes P₀, P₁, P_1,2, P_1,2,3 and P_1,2,3,4, based on their ability to infect systemically Capsicum L⁰ , L¹ , L² , L³ and L⁴ resistant plants, respectively. Two hundred eighty pepper germplasms and 5 reference accessions known as resistant L alleles, were analyzed to select the resistance cultivars against PMMoV- P_1,2,3 (CV130614-2) using bioassay and genetic markers. The susceptible accessions showed systemic symptom when inoculated with PMMoV- P_1,2,3. However, accessions including IT223737, were resistant as they developed necrotic local lesions only on inoculated leaves, whereas no symptoms were observed on the upper leaves. Moreover, RT-PCR results for detecting the presence of virus were also negative. Thus, those accessions will be used as a novel source to facilitate introduction the resistant gene into commercial cultivars of pepper.