• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.108-113
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• 1987

Rice black-streaked dwarf virus(RBSDV) was purified from infected maize leaves. Antiserum against RBSDV was prepared for virus detection by enzyme-linked immunosorbent assay(ELISA). In detection of RBSDV by ELISA, effective dilution range of antiserum extracted in RBSDV-containing host plants and insect vectors was from 320 to 2,560 times in rice plant, 320 to 5,120 in maize plant, and 160 to 2,560 times in insect vector, Laodelphax striatellus F, respectively. The percentage of viruliferous vector in overwintered nymphs of Laodelphax striatellus determined by ELISA were 3.0 in Milyang, 2.3 in Chilgok, and 3.7 in Sunsan area. Dead insect vector which could not be tested for vims infection by conventional rice seedling inoculation test could be tested by ELISA. One hundred plants of rice and maize were randomly sampled in the field and tested whether or not they were infected with RBSDV. In rice plants, 4 out of 98 plants turned out to be infected with RBSDV by ELISA. In maize plant, 3 out of 92 plants which were excepted 8 plants to be appeared symptom already were infected. As a result, ELISA could be detected even in case of symptomless plants at early stage of viral infection.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.381-392
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• 2018

The distribution of mosquitoes collected in the Cheongju area from 2016-2018 were compared. The collection sites were established at a residential area, migratory bird sanctuary, and cowshed using black light (BL) and BG sentinel traps. Culex pipiens was the most collected species in the residential area, and Aedes vexans was the most collected species in the migratory bird sanctuary and cowshed in all years. The BG trap collected more individuals than did the BL trap in the residential area and migratory bird sanctuary. In total, 22,679 (10 species) mosquitoes were collected in 2016, and 6,502 (8 species) and 6,803 (9 species) mosquitoes were collected in 2017 and 2018, accounting for 3.49- and 3.33-fold decreases, respectively. The relationship between meteorological conditions and mosquito density, according to various variables, was not significant different. The Chaoyang virus was found in Aedes vexans and Culex pipiens collected at the cowshed in 2016 and 2018, respectively. Based on the results of this study, it is considered that continuous surveillance of mosquitoes should be performed for controlling mosquito populations and mediating diseases spread by this vector.

• Journal of Life Science
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• v.30 no.3
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• pp.285-290
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• 2020

Foot-and-mouth disease virus (FMDV), a member of the genus Aphthovirus in the Picornaviridae family, affects wild and domesticated ruminants and pigs. FMDV causes various clinical symptoms, including severe inflammation in infected tissue. Genome RNA of FMDV shows a positive single-strand chain approximately 8.3 kb long and encodes a single long open reading frame (ORF). The ORF is translated into structural and non-structural proteins by viral proteases. The FMDV 2C protein is one of the non-structural proteins encoded by FMDV and plays a critical role in FMD pathogenesis, including inflammation, apoptosis, and viral replication. In this study, we examined whether FMDV 2C induces intracellular expression of pro-inflammatory cytokine tumor necrosis factor alpha (TNFα). FMDV 2C expression in pig IBRS-2 cells increased mRNA and protein expression of TNFα at the transcriptional level via activation of TNFα promoter. Treatment with 4-phenylbutyric acid, an endoplasmic reticulum (ER) stress reducer, decreased TNFα expression induced by FMDV 2C. Activating transcription factor 4 (ATF4), a transcription factor mediating ER stress response, induced transactivation of TNFα promoter and expression of mRNA and protein of TNFα. However, the dominant negative mutant of ATF4 did not induce FMDV 2C-mediated TNFα expression. The results indicate that FMDV 2C protein increases clinical inflammation via ATF4-mediated TNFα expression and is associated with ER stress induction.

• Research in Plant Disease
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• v.12 no.3
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• pp.213-220
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• 2006

In year 2003, a soybean(Glycine max) sample showing severe dwarfing symptom was collected from a farmers' field in Cheongsong in Korea. The results from the diagnosis of the sample by RT-PCR revealed that it was infected by Soybean dwarf virus(SbDV), SbDV-L81. This study could be the first report of the occurrence of the virus in Korea. To further characterize the virus, the partial nucleotide sequence of the genomic RNA of SbDV-L81 was determined by RT-PCR using species-specific primers. The sequences were analyzed and subsequently compared to previously characterized strains of SbDV based on the pattern of symptom expression and vector specificities. The intergenic region between ORF 2 and 3 and the coding regions of ORF 2, 3 and 4 were relatively similar to those of dwarfing strains(SbDV-DS and DP) rather than those of yellowing strains(SbDV-YS and YP). Likewise, the result from the analysis of 5'-half of the coding region of ORF5 indicated that SbDV-L81 was closely related to strains(SbDV-YP and DP) transmitted by Acyrthosiphon pisum. These data from the natural symptom and the comparisons of five regions of nucleotide sequences of SbDV suggested that SbDV-L81 might be closely related SbDV-DP.

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.113-120
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• 1986

Soybeans collected from different locations in Korea were planted for tests of seed transmission of soybean mosaic virus (SMV). The percentage of seed transmission ranged from 20.5 to 29.5% in 14 seedlots including soybean cultivar Namhe and 12 to 19% in other 44 seedlots. However, no seed transmission of SMV was observed in soybean cultivar Younkiyongho. SMV was detected from embryo and cotyledon of soybean seeds. The infection of SMV was highly detected from premature seeds than from fully mature seeds, and higher from seeds harvested from plants infected before June 20 than plants infected around July 20 and August 20. No significant relationship was observed between seed transmission of SMV and mottling of seeds. The incidence of soybean mosaic disease followed by one month after peak of aphid population. The number of aphids was less on leaves of soybeans with short and dense trichomes whereas it was higher on leaves of soybean with long and sparse trichomes. Generally, the number of aphids was decreased on leaves with long and dense trichomes as the growth progressed. Soybean cultivar Columbus and 14 cultivars were susceptible, Chief and 14 cultivars were moderate, but Jangbaek and 17 other cultivars were resistant to SMV when inoculated with one isolate of SMV.

• Journal of Life Science
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• v.28 no.9
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• pp.1007-1015
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• 2018

The E6-associated protein (E6AP) is known to induce the ubiquitination and proteasomal degradation of HCV core protein and thereby directly impair capsid assembly, resulting in a decline in HCV replication. To counteract this anti-viral host defense system, HCV core protein has evolved a strategy to inhibit E6AP expression via DNA methylation. In the present study, we further explored the mechanism by which HCV core protein inhibits E6AP expression. HCV core protein upregulated both the protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b to inhibit E6AP expression via promoter hypermethylation in HepG2 cells but not in Hep3B cells, which do not express p53. Interestingly, p53 overexpression alone in Hep3B cells was sufficient to activate DNMTs in the absence of HCV core protein and thereby inhibit E6AP expression via promoter hypermethylation. In addition, upregulation of p53 was absolutely required for the HCV core protein to inhibit E6AP expression via promoter hypermethylation, as evidenced by both p53 knockdown and ectopic expression experiments. Accordingly, levels of the ubiquitinated forms of HCV core protein were lower in HepG2 cells than in Hep3B cells. Based on these observations, we conclude that HCV core protein evades ubiquitin-dependent proteasomal degradation in a p53-dependent manner.

• Journal of Oral Medicine and Pain
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• v.35 no.1
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• pp.93-99
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• 2010

Herpes zoster (HZ) is the secondary manifestation of an earlier infection with the varicella-zoster virus in one or more dermatomes. As reactivation of the virus is linked to an age-related diminished virus-specific and cell-mediated immunity, HZ develops mainly in elderly people. Acute zoster is painful, but does not incur lasting morbidity. Reactivation of the varicella-zoster virus in the trigeminal nerve (Herpes zoster) occur with severe pain and rash in the oro-facial region. The acute pain decreases as the rash begins to heal. Postherpetic neuralgia(PHN), the most frequent complication of herpes zoster, is usually defined as pain in the involved dermatome that is still present 3 month after rash onset. The clinical characteristics of PHN are, eposodic stabbing pain, burning pain and allodynia, with hypoesthesia and/or dysesthesia. $Neurometer^{(R)}$(neuroselective sensory nerve conduction threshold: sNCT, Automated current perception threshold: CPT, neurotron incorporated. Baltimore, Maryland. 21209 U.S.A.) is convenient, rapid and noninvasive, and allows objective assessment of sensory disturbance. This case is about the postherptic neuralgia patient assessed with $Neurometer^{(R)}$. From this case, we reviewed the pathophysiology and the treatment of PHN and recommend the assessment of pain intensity with $Neurometer^{(R)}$ as quantitative and objective method.

• Journal of Life Science
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• v.18 no.9
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• pp.1207-1211
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• 2008

The pro-inflammatory cytokine tumor necrosis factor-$\alpha$ (TNF-$\alpha$) is an important mediator of the immune response in hepatitis B virus (HBV) infection. Since the production of TNF-$\alpha$ is mostly regulated at the transcriptional level and polymorphisms in the TNF-$\alpha$ promoter alter its expression, TNF-$\alpha$ promoter polymorphisms could affect the pathogenesis of chronic HBV infection. In this study, we investigated the potential association of TNF-$\alpha$ promoter polymorphisms with chronic HBV infection. The study included 181 patients with chronic HBV infection, 201 persons who had been spontaneously recovered from hepatitis B, and 170 unrelated healthy controls. The -308G/A and -238G/A polymorphisms in the TNF-$\alpha$ promoter were analyzed by PCR-restriction fragment length polymorphism. The distribution of both the -308 and -238 genotypes in the patient group was not statistically different from that in the spontaneous recovery and control groups (p>0.05). There was also no significant difference in the allele frequency between the groups (p>0.05). The results suggest that the TNF-$\alpha$ -308 and -238 promoter polymorphisms are not associated with the development of chronic HBV infection in the Korean population.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.319-328
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• 2021

Tomato spotted wilt virus (TSWV) is one of the most destructive viruses worldwide, which causes severe damage to economically important crops, such as pepper and tomato. In this study, we examined the molecular and biological characterization of a TSWV isolate (SW-TO2) infecting tomato and compared it to the recently reported isolates from boxthorn, butterbur, and angelica plants. The phylogenetic analysis based on the complete genome sequences confirmed that SW-TO2 was clustered with those of isolates from boxthorn and pepper in Korea with the maximum nucleotide identities ranging from 98% to 99%. We developed the bioassay method for screening TSWV resistance and tested some commercial pepper and tomato cultivars for resistance evaluation of four isolates of TSWV. TSWV resistance was evaluated as TSWV resistance when all the following three conditions were satisfied: first, when symptoms of necrotic spots or no symptoms were present in the inoculated leaves; second, when there were no symptoms in the upper leaves; and third, when the upper leaves were negative as a result of RT-PCR diagnosis.