• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.139-150
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• 1985

In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

• Pediatric Infection and Vaccine
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• v.17 no.2
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• pp.122-129
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• 2010

Purpose : Enteroviral infection is a common viral illness in children. We undertook this study in attempt to comprehend the epidemiologic and clinical features of enteroviral infections, particularly EV71 in children. Methods : We enrolled 63 children with enteroviral infection at Severance Children's Hospital in Seoul between May and August 2009. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed from stool or cerebrospinal fluid samples, which were then tested for enteroviral infection. Viral isolation and serotype identification also were performed by RT-PCR. Results : A total of 63 patients with clinical diagnosis of enteroviral infections were enrolled; of those, 38 (60%) were positive for enterovirus. The mean age of the patients was 2 years and 7 months and the sex ratio of male to female was 0.9 :1. Their clincal manifestations included aseptic meningitis (21 cases, 55%), HFMD (16 cases, 42%), herpangina (5 cases, 13%), neonatal fever (2 cases, 5%), encephalitis (1 case, 3%), and myocarditis (1 case, 3%). Serotypes of isolated enteroviruses were EV71 (8 cases, 21%), coxsackievirus B1 (8 cases, 21%), coxsackievirus A16 (2 cases, 6%), coxsakievirus A2 (1 case, 3%), coxsakievirus A5 (1 case, 3%), and echovirus 9 (1 case, 3%). Clinical symptoms of EV71 infection included HFMD (5 cases, 63%), aseptic meningitis (3 cases, 38%), encephalitis (1 case, 13%), and myocarditis (1 case, 13%). A positive rate of C-reactive protein in EV71 was higher than those in other enterviral infections. However, there was no statistically significant difference in other laboratory findings. Conclusion : We reported on identified enteroviruses, including EV71, during a period of 3 months in the summer of 2009. In this study, EV71 infection frequently occurred in male and clinical manifestation caused by EV71 was a more severe disease than that due to other enterviral infections. There is a need for continuous surveillance of enteroviral infection and its clinical manifestations for diagnosis and treatment of enteroviral infection.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.89-94
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• 2012

Purpose: The option of selecting isotonic rather than hypotonic fluids for maintenance fluid in children has been advocated by some authors. Pneumonia and CNS infections are frequent clinical settings for acute hyponatremia because of nonosmotic anti-diuretic hormone stimuli in children. We conducted the present study to identify the incidence of hyponatremia in pneumonia and CNS infection of children and to determine the importance of maintenance intravenous fluid therapy regimen and other related factors. Methods: The study included 1,992 patients admitted to the Department of Pediatrics at Pusan National University Children's Hospital between November 2008 and August 2011, who were diagnosed with pneumonia or CNS infections and checked for serum sodium concentration. Their clinical data including laboratory findings were reviewed retrospectively. Results: During the study period, 218 patients were identified to have acute hyponatremia among 1,992 patients. The overall incidence of hyponatremia was 10.9%. The incidence of hyponatremia in encephalitis (37.3%) was highest and the incidence in bacterial meningitis (27.4%), viral meningitis (20.0%), bacterial pneumonia (11.1%), mycoplasma pneumonia (9.2%), and viral pneumonia (6.8%) were in descending order. The mean age was higher in hyponatremic patients than in isonatremic patients. The incidence of hyponatremia was higher in who had 0.18% NaCl in 5% dextrose (D5 0.18% NS) than 0.45% NaCl in 5% dextrose infusion (D5 1/2NS) (9.0% vs. 2.2%). SIADH was identified in 20.5% among hospital acquired hyponatremic patients after adequate evaluation for SIADH. Conclusion: We recommend D5 1/2NS rather than D5 0.18% NS as the maintenance fluid given to children with pneumonia or infectious CNS diseases.

• 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.2
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• pp.117-127
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• 2016

Purpose: Vaccine evaluation studies were initiated from 2000 by the Ministry of Food and Drug Safety to produce proper data about the safety and immunogenicity of vaccines. The purpose of this study was to review studies and reports on evaluation of vaccine such as immunogenicity, efficacy, effectiveness, safety and other related topics in order to find and analyze the data on the usefulness of each vaccine. Methods: From 2000 to 2014, the project "The vaccine evaluation" had been performed by several researchers, and studies and reports of vaccine evaluation. We reviewed the results and outcomes of studies regarding the evaluation of vaccine's usefulness and analyzed the possibilities of applying these data for establishing vaccine policies. For each vaccine, data analysis and organization were done according to evaluation fields. Results: A total of 83 studies were performed on vaccines from 2000 to 2014. For each vaccine, 8 studies were performed on BCG, 14 on DTaP/Td, 1 on poliovirus, 5 on Hib, 3 on pneumococcus, 11 on influenza, 3 on hepatitis A, 11 on MMR, 11 on varicella, and 16 on Japanese encephalitis. All studies were analyzed by the following evaluation area, such as safety, immunogenicity, seroprevalence, persistence of immunity, efficacy, effectiveness, vaccine evaluation methods, quality control product for vaccine, and others. Conclusions: Vaccine evaluation studies performed in Korea may be useful as references for establishing vaccination strategy and policy and could be used as baseline data for future studies on vaccine evaluation, vaccine policy establishment, and public/expert vaccine education in Korea.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.99-113
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• 2018

Recently, global warming has widened the habitat of mosquitoes and infection chances for mosquito-borne diseases are increasing. Flavivirus is a typical mosquito-borne virus. Flaviviruses with a relatively high frequency of infection in Asian countries include Zika, Dengue, and Japanese encephalitis viruses. Although distinctive diagnosis of flaviviruses is required because the symptoms and therapeutic method differ, there is no diagnostic method that can distinguish them accurately yet. In this study, we propose distinctive diagnosis method of flaviviruses using informations and analysis tools constructed in bioinformatic databases. The envelope protein and non-structural protein 1 which are useful protein for the immuno-diagnostics of three flaviviruses were selected. Their homology was analyzed by multiple sequence alignments and epitope candidates consisting of 10-15 amino acids were selected. Finally two epitopes were suggested to be most useful by immunogenicity analysis and 3D structure prediction. These approaches and results are expected to be great value in the distinctive diagnosis of three flaviviruses with a high frequency of infection in Asian countries.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1928-1936
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• 2018

Recently, human infections caused by severe fever with thrombocytopenia syndrome virus (SFTSV), which can lead to fatality, have dramatically increased in East Asia. With the unavailability of vaccines or antiviral drugs to prevent and/or treat SFTSV infection, early rapid diagnosis is critical for prevention and control of the disease. Here, we report the development of a simple, rapid and sensitive portable detection method for SFTSV infection applying reverse transcription-loop mediated isothermal amplification (RT-LAMP) combined with one-pot colorimetric visualization and electro-free reaction platform. This method utilizes a pocket warmer to facilitate diagnosis in a resource-limited setting. Specific primers were designed to target the highly-conserved region of L gene of SFTSV. The detection limit of the RT-LAMP assay was approximately $10^0$ viral genome copies from three different SFTSV strains. This assay exhibited comparable sensitivity to qRT-PCR and 10-fold more sensitivity than conventional RT-PCR, with a rapid detection time of 30 to 60 minutes. The RT-LAMP assay using SFTSV clinical specimens has demonstrated a similar detection rate to qRT-PCR and a higher detection rate compared to conventional RT-PCR. Moreover, there was no observed cross-reactive amplification of other human infectious viruses including Japanese Encephalitis Virus (JEV), Dengue, Enterovirus, Zika, Influenza and Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This highly sensitive, electro- and equipment-free rapid colorimetric visualization method is feasible for resource-limited SFTSV field diagnosis.

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.87-92
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• 1986

The present surveys were conducted in attempts to investigate the health situation of horses in Korea through mass-screening the samples serologically, bacteriologically and clinically. A total of 575 horses were sampled randomly, comprising 126 from the Korean Horse Affairs Association, 288 from the Korean Equestrian Federation and 161 from the Jeju ponies. Each of the samples taken was tested for diagnoses of 18 horse diseases including African horse sickness. Summarised below are the results obtained from this surveys. 1. From results of the serological survey it is evident that Korea is currently free from African horse sickness, dourine, glanders, vesicular stomatits, equine piroplasmosis, equine viral arteritis, Venezuelan encephalomyelitis and contagious equine metritis. Constant vigilence with strengthened quarantine measures is thus vital for maintaining freedom of any those diseases in Korea. 2. No clinical case was observed with any of signs or symptoms of infectious lymphangitis, anthrax and infestations with ringworm, mange or scab. However, continuous follow-up is required for establishing the evidence of no occurrence of the diseases in Korea. 3. One case of seropositive to equine infectious anemia may fully justify systematic and regular testings for the whole population of horse in Korea. 4. It is manifested that equine rhinopneumonitis, Japanese encephalitis and Getah virus infection are well established in Korea, together with the presence of equine infectious abortion(Salmonella abortus equi). This strongly entails preventive precautions before entry into Korea for the horses participating in the 1986 Asian Games and the 1988 Seoul Olympics.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.401-408
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• 1987

Nine monoclonal antibodies directed against infectious bovine rhinotracheitis virus (IBRV) were prepared by using cell hybridization technique, and the biological properties of the antibodies were investigated by means of immunofluorescence, serum neutralization, and electrophoretic analysis. Eight of 9 monoclonal antibodies reacted specifically with the antigenic constituents of IBRV, infectious laryngotracheitis virus, Marek's disease virus, turkey herpesvirus, hog cholera virus, porcine parvovirus and transmissible gastroenteritis virus. However, the remaining one, 26-2 clone, was found to be cross-reactive with pseudorabies virus. Two monoclonal antibodies, 7-C-2 and 12-A-2, which had neutralizing activity, were reactive with the molecular weights of 72 kilo daltons (72K) and 125K of IBRV proteins electrophoretically separated, respectively. The monoclonal antibody, 3-H-3, which is corresponding to 94K of IBRV proteins, revealed no neutralizing activity. The cross-reactive monoclonal antibody, 26-2, was proved by electrophoretical analysis to be reactive with 100K of IBRV proteins and 40K of pseudorabies virus.

• Parasites, Hosts and Diseases
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• v.50 no.3
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• pp.199-205
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• 2012

Toxoplasmic encephalitis is caused by reactivation of bradyzoites to rapidly dividing tachyzoites of the apicomplexan parasite Toxoplasma gondii in immunocompromised hosts. Diagnosis of this life-threatening disease is problematic, because it is difficult to discriminate between these 2 stages. Toxoplasma PCR assays using gDNA as a template have been unable to discriminate between an increase or decrease in SAG1 and BAG1 expression between the active tachyzoite stage and the latent bradyzoite stage. In the present study, real-time RT-PCR assay was used to detect the expression of bradyzoite (BAG1)- and tachyzoite-specific genes (SAG1) during bradyzoite/tachyzoite stage conversion in mice infected with T. gondii Tehran strain after dexamethasone sodium phosphate (DXM) administration. The conversion reaction was observed in the lungs and brain tissues of experimental mice, indicated by SAG1 expression at day 6 after DXM administration, and continued until day 14. Bradyzoites were also detected in both organs throughout the study; however, it decreased at day 14 significantly. It is suggested that during the reactivation period, bradyzoites not only escape from the cysts and reinvade neighboring cells as tachyzoites, but also converted to new bradyzoites. In summary, the real-time RT-PCR assay provided a reliable, fast, and quantitative way of detecting T. gondii reactivation in an animal model. Thus, this method may be useful for diagnosing stage conversion in clinical specimens of immunocompromised patients (HIV or transplant patients) for early identification of tachyzoite-bradyzoite stage conversion.