• Journal of Microbiology
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• v.40 no.3
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• pp.183-192
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• 2002

Cells infected With equine herpesvirus type-1 (EHV-1) Produced both infectious and non-infectious Virus-related particles. Compared to the whole virion, non-infectious particles termed L-particles were deter-mined to lack 150 kDa protein, commonly known as nucleocapsid protein. The potential of L-particles to induce immune responses was studied in mice and foals. Intranasal immunization with L-particles or whole virions induced poor IgG antibody responses in mice. Interestingly, despite the poor antibody response, the conferred immunity protected the host from challenge infections. This was indicated by a significant reduction in virus titers in line with recovery towards normal body weight. Subsequently, the test on the usefulness of L-particles as immunizing agents was extended to foals. Immunization of specific-pathogen-free (SPF) foals resulted in similar results. As determined by a complement-fixing-antibody test (CFT), foals seroconverted when they were immunized either with inactivated L-particles or whole virions via intramuscular (i.m.) injections. The presence of the antibody correlated with the degree of protection. Beyond day 1 post challenge infection (p.i.), there was no virus shedding in the nasal mucus of foals immunized with whole EHV-1 virions. Virus shedding was observed in foals Immunized with L-particles but limited to days 6 to 8 p.i. only. In contrast, extended vim shedding was observed in non-immunized foals and it was well beyond day 14 p.i. Viremia was not detected for more than four days except in non-immunized foals. Immunization in mice via intranasal (i.n.) conferred good protection. However, compared to the i.n. route, a greater degree of protection was obtained in foals following immunization via i.m. route. Despite variation in the degree of protection due to different routes of immunization in the two animal species, our results have established significant evidence that immunization with L-particles confers protection in the natural host. It is suggested that non-infectious L-particles should be used as immunizing agents for vaccination of horses against EHV-1 infection.

• Korean Journal of Environmental Biology
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• v.41 no.1
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• pp.1-13
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• 2023

Broad bean wilt virus 2 (BBWV2) is a species in the genus Fabavirus and family Secoviridae, which is transmitted by aphids and has a wide host range. The BBWV2 genome is composed of two single-stranded, positive-sense RNAs, RNA-1 and RNA-2. The representative symptoms of BBWV2 are mosaic, mottle, vein clearing, wilt, and stunting on leaves, and these symptoms cause economic damage to various crops. In 2019, Perilla fructescens leaves with mosaic and yellowing symptoms were found in Geumsan, South Korea. Reverse-transcription polymerase chain reaction (RT-PCR) was performed with specific primers for 10 reported viruses, including BBWV2, to identify the causal virus, and the results were positive for BBWV2. To characterize a BBWV2 isolate (BBWV2-GS-PF) from symptomatic P. fructescens, genetic analysis and pathogenicity tests were performed. The complete genomic sequences of RNA-1 and RNA-2 of BBWV2-GS-PF were phylogenetically distant to the previously reported BBWV2 isolates, with relatively low nucleotide sequence similarities of 76-80%. In the pathogenicity test, unlike most BBWV2 isolates with mild mosaic or mosaic symptoms in peppers, the BBWV2-GS-PF isolate showed typical ring spot symptoms. Considering these results, the BBWV2-GS-PF isolate from P. fructescens could be classified as a new strain of BBWV2.

• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.294-300
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• 1999

In this study PRRSV was isolated from serum of an infected pig and designated as CNV-1, ORF4 gene was sequenced, and the nucleotide sequence, deduced amino acid sequence and the amino acid sequence of the neutralizing domain was compared with other PRRSV Strains. ORF4 gene of the Korean isolate PRRSV CNV-1 was shown to be 537bp in length, which is the same as US strain ISU55 but 21bp longer than another US strain MN1b, and 15bp shorter than European strain LV. The homologies of the nucleotide sequences between the Korean isolate CNV-1 and the US strains ISU55, MN1b and European strain LV were 91.8%, 88.1%, 67.6%, respectively, and the homologies of the deduced amino acid sequences were 94.4%, 84.4%, 68.5%, respectively. The neutralizing domain of the CNV-1 was shown to be 36 amino acids in length which is the same as ISU55, MN1b, but 4 amino acids shorter than that of the neutralizing domain reported in LV. The homologies of the amino acid sequences of the neutralizing domain between the Korean isolate CNV-1 and the US strains ISU55, MN1b and European strain LV were 92.5%, 85%, 57.5%, respectively. The molecular characteristics of ORF4 gene of the Korean isolate PRRSV CNV-1 shown in this study suggests that the CNV-1 is genetically closer to the US strains. Also the wide variation of the neutralizing domain between the CNV-1 and LV suggests that there is substantial immunogenic variation between the two strains.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.174-182
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• 2007

In this paper, we study the influence of infection ratio on gradual reduction of drug dose for the five state HIV infection model that explicitly includes the population of the virus. We first compute all equilibrium points of the model and investigate the stabilities of them. As a result, a bifurcation diagram is obtained which shows a change in the equilibrium points, or in their stability properties, as the drug effect $\eta$ is varied from 0 to 1(alternatively, drug dose is changed from 1 to 0). Based on the bifurcation diagram, we show that the gradual reduction of drug dose can be applied for the treatment of AIDS patients. Moreover, we analyze the influence of the variation of infection ratio on the gradual reduction treatment. Computer simulation results are also presented to validate the proposed results.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.12
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• pp.597-603
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• 2001

In the mathematical model for the transmission dynamics of HIV infection described in previous papers, the population under consideration is assumed to be homogeneous community of homosexual males for which the parameter x represents the constant rate at which individual members of the population acquire new sexual partners. This is a gross oversimplification since it is well known that individuals vary widely in their levels of sexual activity and in this papers the heterogeneous model is modified to allow for this variation. The pattern on the epidemic character of HIV, the causative agent of AIDS, was analysed by heterogeneous-mixing model. The computer simulation was performed using real date.

• Genomics & Informatics
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• v.10 no.4
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• pp.234-238
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• 2012

Genetic epidemiology studies have established that the natural variation of gene expression profiles is heritable and has genetic bases. A number of proximal and remote DNA variations, known as expression quantitative trait loci (eQTLs), that are associated with the expression phenotypes have been identified, first in Epstein-Barr virus-transformed lymphoblastoid cell lines and later expanded to other cell and tissue types. Integration of the eQTL information and the network analysis of transcription modules may lead to a better understanding of gene expression regulation. As these network modules have relevance to biological or disease pathways, these findings may be useful in predicting disease susceptibility.

• Proceedings of the Korean Society of Crop Science Conference
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• 2007.11a
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• pp.211.1-211.1
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• 2007

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.39-45
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• 1987

Daunomycin, an anthracycline antibiotic, has been found to inhibit virus multiplication and shows considerable activity against tumors. Its activity may be varied by conformational changes of daunomycin. The conformational changes are come from the pucker of D-ring and variation of environments. We have carried out conformational analyses by using empirical potential function. We found that when daunomycin is hydrated or bound to $Mg^{2+}$ ion, the minimum conformer of each state is altered from ${\alpha}$ conformer to ${\beta}$ conformer through the pathway having four local minima. Our calculated results are in good agreements with those of X-ray crystallography and biological experiments, in which metal ion inhibits the binding of daunomycin to DNA.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48
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• pp.49-57
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• 2003

There is much evidence suggesting that compounds present in soybean can prevent cancer in many different organ systems. Especially, soybean is one of the most important source of dietary saponins, which have been considered as possible anticarcinogens to inhibit tumor development and major active components contributing to the cholesterol-towering effect. Also they were reported to inhibit of the infectivity of the AIDS virus (HIV) and the Epstein-Barr virus. The biological activity of saponins depend on their specific chemical structures. Various types of triterpenoid saponins are present in soy-bean seeds. Among them, group B soyasaponis were found as the primary soyasaponins present in soybean, and th e 2, 3-dihydro-2, 5-dihydroxy-6- methyl-4H-pyran-4-one(DDMP)-conjugated soyasaponin $\alpha\textrm{g}$, $\beta\textrm{g}$, and $\beta$ a were the genuine group B saponins, which have health benefits. On the other hand, group A saponins are responsible for the undesirable bitter and astringent taste in soybean. The variation of saponin composition in soybean seeds is explained by different combinations of 9 alleles of 4 gene loci that control the utilization of soyasapogenol glycosides as substrates. The mode of inheritance of saponin types is explained by a combination of co-dominant, dominant and recessive acting genes. The funtion of theses genes is variety-specific and organ specific. Therefore distribution of various saponins types was different according to seed tissues. Soyasaponin $\beta\textrm{g}$ was detected in both parts whereas $\alpha\textrm{g}$ and $\beta$ a was detected only in hypocotyls and cotyledons, respectively. Soyasaponins ${\gamma}$g and $\gamma\textrm{g}$ were minor saponin constituents in soybean. In case group A saponins were mostly detected in hypocotyls. Also, the total soyasaponin contents varied among different soy-bean varieties and concentrations in the cultivated soy-beans were 2-fold lower than in the wild soybeans. But the contents of soyasaponin were not so influenced by environmental effects. The composition and concentration of soyasaponins were different among the soy products (soybean flour, soycurd, tempeh, soymilk, etc.) depending on the processing conditions.

• Journal of Life Science
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• v.19 no.10
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• pp.1451-1455
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• 2009

Porcine cytomegalovirus (PCMV) is a betaherpesvirus which causes reproductive failure in breeding sows and generalized infection in newborn piglets. It has worldwide distribution including Korea. Serological survey on this virus has been reported in 76.3% of pigs, but virological survey and epidemiological analysis on PCMV distribution have been reported in only a few papers in Korea. In this study, we investigated the virological prevalence and infection status of PCMV on a farm level in selected swine farms with respiratory diseases. A total of 1,938 blood samples taken from groups of pigs of different ages were collected from 31 farms distributed nationwide in 2006 and 2007 and tested by PCR to detect the presence of PCMV. Virological prevalence at farm level and pig level were 96.8% and 17.5%, respectively, suggesting that PCMV has endemically infected Korean pig herds. The prevalence at farm level in gilts, sows and suckling piglet groups were 16.7%, 36.7% and 56.7%, indicating that vertical infections frequently occurred in conception or newborn stage. Thereafter, detection rates of PCMV were slightly increased in pig groups aged 40 and 70 days (70.0% and 73.3%), and then gradually decreased as they aged - 33.3% in 100, 26.7% in 130 and 16.7% in 160 day old pig groups. The prevalence at pig level has similar patterns to that at farm level. With the passage of time, the variation of infection patterns of PCMV was investigated in four PCMV-positive farms. Three blood samples were collected at intervals of 6 months in each farm, and examined for presence of PCMV using PCR. The results revealed that once PCMV was introduced to the pig farms, it continuously circulated between and within groups of sows and piglets in those farms. Taken together, it can be concluded that PCMV has endemically infected Korean pig farms and has the potential risk for emerging pathogen in combination with the known endemic pathogens including porcine reproductive, respiratory syndrome virus and porcine circovirus type 2. Therefore, more research is needed on diagnosis, epidemiology and control strategy for PCMV on the field.