• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.38-42
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• 2018

Demand for tomatoes has been increasing every year as people desire more healthy food. In Korea, tomatoes are mainly grown in the Chungnam, Chunnam and Kyungnam provinces. Recently, reports of whitefly-transmitted viral diseases have increased due to newly emerging whitefly pressures caused by climate change in Korea. Specifically, in 2017, the main tomato growing areas, Buyeo and Nonsan in Chungnam, showed damage typical of viral infection; therefore, we investigated viral diseases in these areas. We collected samples with virus-like symptoms and found that not only whitefly transmitted Tomato yellow leaf curl virus (TYLCV) and Tomato chlorosis virus (ToCV) were detected but also Tomato mosaic virus (ToMV, for which no specific vector is known) and Tomato spotted wilt virus (TSWV, transmitted by thrips). The ToMV-infected samples were mostly co-infected with either TYLCV or ToCV. Mixed infections of different combinations of TYLCV, ToCV and ToMV were detected with the mixed infection of two whitefly-transmitted viruses (TYLCV and ToCV) causing the most severe symptoms. According to the CP sequence of each virus, the 100% identities were shown to be Mexico/ABG73017.1 (TYLCV), Greece/CDG34553.1 (ToCV), China/AKN79752 (TSWV), and Australia/NP078449.1 (ToMV). Based on the sequence data, we presumed that these tomato infecting viruses were transmitted through insects and seeds introduced from neighboring countries.

• Molecules and Cells
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• v.27 no.1
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• pp.105-111
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• 2009

Gammaherpesvirus infection of the central nervous system (CNS) has been linked to various neurological diseases, including meningitis, encephalitis, and multiple sclerosis. However, little is known about the interactions between the virus and the CNS in vitro or in vivo. Murine gammaherpesvirus 68 (MHV-68 or ${\gamma}HV-68$) is genetically related and biologically similar to human gammaherpesviruses, thereby providing a tractable animal model system in which to study both viral pathogenesis and replication. In the present study, we show the successful infection of cultured neuronal cells, microglia, and astrocytes with MHV-68 to various extents. Upon intracerebroventricular injection of a recombinant virus (MHV-68/LacZ) into 4-5-week-old and 9-10-week-old mice, the 4-5-week-old mice displayed high mortality within 5-7 days, while the majority of the 9-10-week-old mice survived until the end of the experimental period. Until a peak at 3-4 days post-infection, viral DNA replication and gene expression were similar in the brains of both mouse groups, but only the 9-10-week-old mice were able to subdue viral DNA replication and gene expression after 5 days post-infection. Pro-inflammatory cytokine mRNAs of tumor necrosis factor-${\alpha}$, interleukin $1{\beta}$, and interleukin 6 were highly induced in the brains of the 4-5-week-old mice, suggesting their possible contributions as neurotoxic factors in the age-dependent control of MHV-68 replication of the CNS.

• Pediatric Infection and Vaccine
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• v.23 no.1
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• pp.40-45
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• 2016

Purpose: The purpose of this study was to investigate the etiology of acute pharygotonsillitis in pediatric patients. Methods: Pharyngeal swabs from patients with acute pharyngotonsillitis were evaluated for viruses and bacterial organisms from March 2010 through March 2011. Results: Of 615 patients, potentially pathogenic bacteria were isolated in 40 (6.5%), viruses were isolated in 310 (50.4%), and no pathogens were isolated in 267 patients (43.4%). Both viral and bacterial pathogens were found in 2 (0.3%). Of 40 patients with bacterial pathogens, group A streptococci were found in 31 (77.5%). Among 310 patients with virus infection, adenovirus was the most frequently recovered (203 patients; 65.5%), followed by rhinovirus (65 patients; 21.0%), enterovirus (43 patients; 13.9%) and coronavirus (18 patients; 5.8%). There were 25 patients who had been coinfected with 2 viruses. In viral pharyngotonsillitis, cough, rhinorrhea, conjunctivitis and diarrhea were prominent. On the other hand, pharyngeal injection and pharyngeal petechiae were prominent in bacterial pharyngotonsillitis. Conclusions: Virus infection was a big part of acute pharyngotonsillitis and there were differences in clinical manifestations among viral and bacterial infections. Therefore, we need to distinguish between virus infection and bacterial infection using clinical signs for preventing the abuse of antibiotics.

• Journal of fish pathology
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• v.27 no.1
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• pp.35-45
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• 2014

In this study, we investigated the effects of dietary 1% garlic extract on nonspecific immune responses and fish diseases (Viral Hemorrhagic Septicemia Virus, Vibrio anguillarum, Streptococcus iniae and Edwardsiella tarda) resistance in olive flounder Paralichthys olivaceus. Fish were fed a commercial diets supplemented with 1% garlic extract for 4 weeks. After the 4 weeks feeding experiment, the artificial infection was made by V. anguillarum, S. iniae, E. tarda and VHSV. And the cumulative mortality was monitored for 2 weeks after artificial infection. The cumulative mortalities decreased in all experiments except for group of E. tarda compared to control group. We observed significantly higher levels of the hematocrit, glucose, total protein, lysozyme activity and the macrophage activity in the experimental group compared to the control group. In the experiments of drug sensitivity and MIC using the three bacteria (V. anguillarum, S. iniae and E. tarda), 1% garlic extract was more effective than the previously reported fermented garlic powder. These results suggested that garlic extract can increase the disease resistance of olive flounder against V. anguillarum, S. iniae and VHSV and the ability of nonspecific immune responses.

• Korean Journal of Ichthyology
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• v.30 no.4
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• pp.185-193
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• 2018

From 2017 to 2018, the disease has been monitored at four culturing eel farms in Incheon and Gyeonggi region in Korea. As a result, diseases with gill congestion frequently occurred. This disease occurred regardless of size of eel, but the frequency and cumulative mortality were high in eels within 3 months after stocking. The infected fish showed pathological histopathological features such as intense congestion and dilation in the central venous sinus (CVS) of gill filaments and hemorrhages in liver and kidney. Hexagonal viral particles measuring about 70 nm in diameter was observed in nuclei and cytoplasm of gill vascular endothelial cells. Molecular biologic diagnosis by both PCR and genetic analysis has been revealed that the causative agent of this disease is Japanese eel endothelial cells-infecting virus (JEECV), the cause of viral endothelial cell necrosis of eel (VECNE), which is mainly reported in Japan. This study is the first report on the characteristics of JEECV and VECNE infection in domestic eel farms.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1154-1158
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• 2013

Ganciclovir resistance of human cytomegalovirus is associated with mutations in the viral UL97 gene and poses severe problems for immunocompromised patients. In this study, PCR-based restriction fragment length polymorphism and sequencing analyses detected the UL97 D605E mutation in all five clinical isolates from patients with ganciclovir-resistant human cytomegalovirus infection during prolonged ganciclovir therapy, whereas the M460V mutation was only present in 1 of 5 isolates. On the other hand, the detection rates of the D605E mutation in the stored available DNA samples from the donor and allogeneic stem cell transplantation recipients were 66.7% and 93.7%, respectively, suggesting that the presence of D605E mutation was not associated with the ganciclovir exposure. Although the D605E mutation may not be related to ganciclovir resistance, we suggest that this mutation could be an important molecular marker of human cytomegalovirus evolution in East Asian countries. Moreover, the restriction fragment length polymorphism method using the restriction enzyme HaeIII, which is generally used to detect the UL97 A591V mutation, could also detect the D605E mutation and may therefore be a useful tool for future research on the investigation of UL97 gene mutations.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.167-174
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• 1985

It has been well recognized that the various cutaneous manifestations associated with the liver diseases. A clinical study was made of 255 patients (AVH 84, LC 70, HC 41, CAH 26, CPH 23, AH11) with the liver diseases at Yeungnam University Hospital during the periods from May to November, 1985. The authors classified the cutaneous manifestations into 7 groups according to pathogenesis, and compared them with other reports. The results were as follows; 1. In 255 patients with various liver diseases, 161 patients (63%) showed the various cutaneous manifestations. 2. The various cutaneous manifestations were jaundice and/or pruritus (43.1%), vascular changes (39.6%), allergic manifestations (10.6%), nail changes (5.1%), hormone-induced changes (4.3%), pigmentary changes (3.5%) and others (2.4%) in that order. 3. Cutaneous manifestations were associated most frequently with liver cirrhosis (1.6 groups) and the least with chronic active hepatitis (0.7 group). 4. Allergic manifestations were seen mainly in patients with acute viral hepatitis. Three patients showed the serum sickness-like prodrome. 5. The other cutaneous manifestations were seen mainly in patients with chronic liver diseases.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.561-566
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• 2021

Schools are highly feared to spread widely in the event of an infectious disease, and systematic management and prompt response are needed as it can undermine students' health and learning rights. This study was conducted to identify the current status of infectious diseases common to elementary, middle and high school students and to provide basic data to protect students and faculty from the threat of infectious diseases and maintain normal school functions. Sejong City was selected for investigation. The three major infectious diseases are influenza, chickenpox and aquarium, all of which are classified as acute viral infectious diseases and have fast propagation speed and strong propagation power, which can have fatal consequences for students living in groups. The research data were analyzed using the 2019 infectious disease report data from the Education Ministry's Education Administration Information Network (NEIS), and the current status data reported by elementary, middle and high schools nationwide were analyzed. The research method was to compare the current status of infectious diseases across the country and Sejong City, compare the status of issuance by each school level, compare the status of infectious diseases by item, and analyze the status of infectious diseases by time. The results of the survey on the status of the three major infectious diseases are expected to be used as basic data for managing infectious diseases not only in Sejong City but also in the nation, so that they can be used to establish measures to manage student infectious diseases in the future.

• Korean Journal of Poultry Science
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• v.40 no.4
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• pp.299-304
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• 2013

Tracheal epithelial cells (TECs) are an important tool for studies of viral respiratory diseases. Primary TECs have been cultured from human, mouse and hamster. It is also necessary to diagnose viral respiratory disease and reveal infection mechanisms in chicken. In this study, we isolated tracheal epithelial layers from tracheal of 20-day-old chicks and cultured primary TECs from the isolated layers. Ciliated cells which were a typical morphology of TECs were observed in cultured primary TECs and maintained until cell passage 5 (15 to 20 days). When we analyzed expression patterns of epithelial marker genes (retinoic acid responder, FGF-binding protein, virus activating protease (VAP) in TECs compared to immortalized chicken embryonic fibroblast cell line (DF-1), all the marker genes are highly expressed in TECs than in DF-1. When TECs were cultured with 0.1 and 1 MOI of ND virus (rNDV-GFP strain) to test the susceptibility of TECs for ND virus, 12.6% and 48.2% of the incubated TECs were infected respectively. In addition, when DF-1 was incubated with 1 MOI of ND virus, the virus infection rate of DF-1 was three times lower than the virus infection rate of TECs. These data could contribute to study infection mechanisms of viral respiratory diseases and control them in chicken.

• Korean Journal of Veterinary Service
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• v.43 no.3
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• pp.113-128
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• 2020

For estimating the prevalence of bovine infectious disease agents, the pathogens were classified as follows: the digestive disease agents, respiratory disease agents, reproductive disease agents, and tick-borne disease agents. This study covered 81 published papers regarding bovine infectious diseases in Korea that determined the presence of diverse pathogens or the antibodies elicited by the infectious agents in cattle from 2010 to 2019. In total, 59,504 cows were involved in the papers reporting the causative agents in their cases. The disease prevalence for the digestive, respiratory, reproductive, and tick-borne cases was 9.0%, 13.4%, 10.4%, and 7.8%, respectively. Bovine viral diarrhea virus, Escherichia coli, Mycobacterium avium subsp. paratuberculosis, and Eimeria spp were more significantly prevalent in the cows under one-year age than over one-year age. Bovine viral diarrhea virus, Escherichia coli, Mycobacterium avium subsp. paratuberculosis, and Anaplasma spp. were more significantly prevalent in Hanwoo than dairy cattle. Coxiella burnetii, Neospora caninum, and Theilieria spp. were more significantly prevalent in dairy cattle than Hanwoo. Tick-borne disease agents were more prevalent in cows grazing than the case in housing. Our analytic data obtained from this study emphasize the need for more studies on the occurrence of these pathogens according to the breed, age, and the region, to come up with bovine infectious disease control measures in Korea.