• The Journal of Korean Society of Virology
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• v.28 no.3
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• pp.267-274
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• 1998

Human cytomegalovirus (HCMV) has the ability to activate the expression of many viral and cellular genes. Among various viral proteins, the immediate early proteins (IE1-72kDa, IE2-86kDa) have been known to be potent transactivators. The product of c-jun proto-oncogene is important in cell activation and differentiation. Here, we tried to find out if the IE could activate the c-jun promoter and also tried to identify the responsible sequence elements in the c-jun activation by IE1-72kDa. We found HCMV IE expression transactivated the c-jun promoter in human embryonal lung fibroblasts (HEL). The activation fold by IE1-72kDa, IE2-86kDa and IE2-55kDa was 23, 35, and 5, respectively. When the expression of each IE was combined, it showed synergism. Expression of (IE1-72kDa + IE2-86kDa) and (IE1-72kDa + IE2-86kDa + IE2-55kDa) resulted in 131 and 162 fold increase, respectively. The c-jun promoter region between -117 and -59 contains binding sites for the transcription factors Spl, CAAT, AP-l like (ATF/CREB), and MEF2. Transient expression assays were performed using various reporter plasmids containing the c-jun promoter-regulatory region linked to the luciferase gene and a plasmid expressing HCMV IE1 gene. Deletional and point mutational analysis showed that the sequence between -225 to -160 and the CTF binding site were involved in the up-regulation of c-jun promoter.

• The Journal of Korean Society of Virology
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• v.29 no.2
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• pp.129-136
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• 1999

Transient transfection assay has been done to evaluate whether the c-jun activation would be prerequisite to the induction of permissiveness against human cytomegalovirus using in vitro cell model in which U937 has been induced to express CD11b and CD14 to become potential monocyte/macrophage cells by TPA treatment. U937 cells were treated with $10\;{\mu}M$, $50\;{\mu}M$ or $100\;{\mu}M$ of TPA. The cell morphology change was observed and the expression of the CD11b and CD14 was confirmed by FACS. Differentiated cells were transfected with pJLuc reporter vector which contained the wild type murine c-jun promoter spanning the SP1, CTF, ATF/CREB and MEF-2 binding sites upstream of the firefly luciferase gene. After 48 hrs of transfection, the cells were infected with HCMV Towne strain and the luciferase activity was assessed at 1 hand 4 h pi. The transfection assay showed no activation of the c-jun promoter at 1 h pi, instead, it showed 2 times increase of the its activity at 4 h pi. There was no difference of the c-jun promoter activation between TPA treated and untreated U937 cells, implying that c-jun activation might not be prerequisite for allowing cells to be premissive to HCMV, although HCMV infection itself could activate c-jun promoter.

• Toxicological Research
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• v.34 no.3
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• pp.191-197
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• 2018

In 2015, a candidate for the second national reference standard (NRS) of Gloydius snake venom was produced to replace the first NRS of Gloydius snake venom. In the present study, the potencies of the candidate were determined by a collaborative study, and the qualification of the candidate was estimated. The potencies of the candidate were determined by measuring the murine lethal titers and lapine hemorrhagic titers of venom against the regional working reference standard (RWRS) for antivenom using the methods described in the previous report for the first NRS of Gloydius snake venom. Three Korean facilities contributed data from a total of 30 independent assays. Subsequently, two foreign national control research laboratories contributed to this collaborative study. The results were calculated using the Reed-Muench method for lethality and determined using a mixed-effects model for hemorrhage. The general common potencies of the lethal and hemorrhagic titers were obtained from the results of the 30 tests performed at three Korean facilities. The results are expressed in micrograms for 1 test dose (TD) with a 95% confidence interval as follows: a lethal titer of $90.13{\mu}g/TD$ (95% confidence interval = $87.39{\sim}92.86{\mu}g$) and a hemorrhagic titer of $10.80{\mu}g/TD$ (95% confidence interval = $10.46{\sim}11.14{\mu}g$). In addition, the candidate preparation showed good quality evaluation according to the results of the quality estimation of the candidate and is judged to be suitable to serve as the Korean NRS for snake venom. In conclusion, the second NRS of Gloydius snake venom was established in this study and will be used for national quality control, including a national lot release test of Korean antivenom products.

• Parasites, Hosts and Diseases
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• v.49 no.1
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• pp.85-90
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• 2011

Relatively little has been studied on the AMA-1 vaccine against Plasmodium vivax and on the plasmid DNA vaccine encoding P. vivax AMA-1 (PvAMA-1). In the present study, a plasmid DNA vaccine encoding AMA-1 of the reemerging Korean P. vivax has been constructed and a preliminary study was done on its cellular immunogenicity to recipient BALB/c mice. The PvAMA-1 gene was cloned and expressed in the plasmid vector UBpcAMA-1, and a protein band of approximately 56.8 kDa was obtained from the transfected COS7 cells. BALB/c mice were immunized intramuscularly or using a gene gun 4 times with the vaccine, and the proportions of splenic T-cell subsets were examined by fluorocytometry at week 2 after the last injection. The spleen cells from intramuscularly injected mice revealed no significant changes in the proportions of CD8$^+$ T-cells and CD4$^+$ T-cells. However, in mice immunized using a gene gun, significantly higher (P<0.05) proportions of CD8$^+$ cells were observed compared to UB vector-injected control mice. The results indicated that cellular immunogenicity of the plasmid DNA vaccine encoding AMA-1 of the reemerging Korean P. vivax was weak when it was injected intramuscularly; however, a promising effect was observed using the gene gun injection technique.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.447-453
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• 2015

The infection status of fishborne zoonotic trematode (FZT) metacercariae was investigated in fishes from 2 localities of Lao PDR. Total 157 freshwater fishes (17 species) were collected in local markets of Vientiane Municipality and Champasak Province in December 2010 and July 2011, and each fish was examined by the artificial digestion method. Total 6 species of FZT metacercariae, i.e., Opisthorchis viverrini, Haplorchis taichui, Haplorchis yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium, were detected in fishes from Vientiane Municipality. The metacercariae of O. viverrini were detected in 50 (49.5%) out of 101 fishes (6 species), and their average number was 154 per fish infected. The remaining 5 species of heterophyid metacercariae were detected in 36.8%, 65.8%, 9.4%, 23.9%, and 5.1% fishes examined, and their average densities were 12, 1,038, 4, 15, and 13 per infected fish, respectively. In fishes from Champasak Province, 3 species of FZT metacercariae, i.e., O. viverrini, H. taichui, and H. yokogawai, were detected. Only 2 O. viverrini metacercariae were found in only 1 Barbonymus schwanefeldi. The metacercariae of H. taichui and H. yokogawai were detected in 60.0% and 50.0% of fishes examined, and their average densities were 47 and 28 per fish infected. By the present study, it has been confirmed that several species of FZT metacercariae are prevalent in fishes from Vientiane Municipality, with P. varium being a new member of FZT in Lao PDR. In comparison, FZT metacercariae are less prevalent in fishes from Champasak Province.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.439-445
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• 2015

A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.1-7
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• 2014

Plasmodium vivax reemerged in the Republic of Korea (ROK) in 1993, and is likely to continue to affect public health. The purpose of this study was to measure levels of anti-P. vivax antibodies using indirect fluorescent antibody test (IFAT) in border areas of ROK, to determine the seroprevalence of malaria (2003-2005) and to plan effective control strategies. Blood samples of the inhabitants in Gimpo-si, Paju-si, and Yeoncheon-gun (Gyeonggi-do), and Cheorwon-gun (Gangwon-do) were collected and kept in Korea Centers for Disease Control and Prevention (KCDC). Out of a total of 1,774 serum samples tested, the overall seropositivity was 0.94% (n=17). The seropositivity was the highest in Paju-si (1.9%, 7/372), followed by Gimpo-si (1.4%, 6/425), Yeoncheon-gun (0.67%, 3/451), and Cheorwon-gun (0.19%, 1/526). The annual parasite incidence (API) in these areas gradually decreased from 2003 to 2005 (1.69, 1.09, and 0.80 in 2003, 2004, and 2005, respectively). The highest API was found in Yeoncheon-gun, followed by Cheorwon-gun, Paju-si, and Gimpo-si. The API ranking in these areas did not change over the 3 years. The seropositivity of Gimpo-si showed a strong linear relationship with the API of 2005 (r=0.9983, P=0.036). Seropositivity data obtained using IFAT may be useful for understanding malaria prevalence of relevant years, predicting future transmission of malaria, and for establishing and evaluating malaria control programs in affected areas.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.305-311
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• 2013

In this study, we found that Haplorchis taichui, a heterophyid intestinal fluke, is highly prevalent, with heavy worm loads, among riparian people in Saravane and Champasak province, Lao PDR. Fecal specimens were collected from 1,460 people (717 men and 743 women) in 12 riparian (Mekong river) districts and were examined by the Kato-Katz fecal smear technique. The overall helminth egg positive rate was 78.8% and 66.4% in Saravane and Champasak province, respectively. The positive rate for small trematode eggs (STE), which included H. taichui and other heterophyids, Opisthorchis viverrini, and lecithodendriids, was 69.9% and 46.3% in Saravane and Champasak province, respectively. To obtain adult flukes, 30 STE-positive people were treated with 40 mg/kg praziquantel and then purged. Whole diarrheic stools were collected 4-5 times for each person and searched for fluke specimens using a stereomicroscope. Mixed infections with various species of trematodes (H. taichui, Haplorchis pumilio, O. viverrini, Prosthodendrium molenkampi, Centrocestus formosanus, and Echinochasmus japonicus) and a species of cestode (Taenia saginata) were found. However, the worm load was exceptionally high for H. taichui compared with other trematode species, with an average of 21,565 and 12,079 specimens per infected person in Saravane and Champasak province, respectively, followed by H. pumilio (41.9 and 22.5, respectively) and O. viverrini (9.4 and 1.5, respectively). These results show that diverse species of intestinal and liver flukes are prevalent among riparian people in Saravane and Champasak province, Lao PDR, with H. taichui being the exceptionally dominant species.

• Journal of Preventive Medicine and Public Health
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• v.50 no.3
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• pp.195-200
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• 2017

Objectives: Q fever is a zoonotic disease that occurs worldwide; however, little is known about its prevalence in South Korea. We attempted to determine the prevalence of Q fever seroreactivity among Korean slaughterhouse workers and the risk factors for seroreactivity according to the type of work. Methods: The study was conducted among 1503 workers at a total of 73 slaughterhouses and 62 residual-product disposal plants. During the study period, sites were visited and surveys were administered to employees involved in slaughterhouse work, and serological tests were performed on blood samples by indirect immunofluorescence assays. Serological samples were grouped by job classification into those of slaughter workers, residual-product handlers, inspectors and inspection assistants, and grading testers and testing assistants. Employee risk factors were analyzed according to the type of work. Results: Out of 1481 study subjects who provided a blood sample, 151 (10.2%) showed reactive antibodies. When these results were analyzed in accordance with the type of work, the result of slaughter workers (11.3%) was similar to the result of residual-product handlers (11.4%), and the result of inspectors and assistants (5.3%) was similar to the result of grading testers and assistants (5.4%). Among those who answered in the affirmative to the survey question, "Has there been frequent contact between cattle blood and your mouth while working?" the proportions were 13.4 and 4.6%, respectively, and this was identified as a risk factor that significantly varied between job categories among slaughterhouse workers. Conclusions: This study found a Q fever seroreactivity rate of 10.2% for slaughterhouse workers, who are known to be a high-risk population. Contact with cattle blood around the mouth while working was the differential risk factor between job categories among slaughterhouse workers.

• Journal of Mushroom
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• v.8 no.1
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• pp.16-21
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• 2010

Sparassis crispa(Cauliflower mushroom) was an edible mushroom that shows remarkably high contents of 1.3-${\beta}$-Dglucan compared to other edible mushroom. The mushroom was known to give high antitumor and immunology activated, and then this mushroom was recently cultivated in Japan and Korea. However, cultivation methods ware becoming kept in secret or patents by some companies with complicated procedures. And it was not established cultivation methods of Sparassis crispa up to now. This study was conducted to solve the problem by short-log cultivation method of Sparassis crispa. Some factors effecting on the mycelial growth and primordial formation of Sparassis crispa were investigated. We could produce the mushroom using short-woods of Larix leptolepis, Pinus densiflora, Pinus rigida and Quercus acutissima. We get to high yield fruit-body on short-log cultivaiton of Pinus rigida. And soaking for 8hours in water solution containing 5% uncooked yeast with short-wood of Pinus rigida. The optimal moisture content and temperature were 90~95% and $23{\sim}25^{\circ}C$, respectively.