• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.209-216
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• 1997

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NlH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.31-36
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• 2017

Japanese encephalitis (JE) is an important zoonosis caused by the mosquito-transmitted JE virus (JEV), which is a causative agent of reproductive failure in pregnant sows. Detection of JEV antibodies in swine is performed by hemagglutination inhibition (HI), virus neutralization (VN), and the plaque reduction neutralization test (PRNT). The most stringent PRNT is the 90% endpoint PRNT ($PRNT_{90}$). These conventional assays are difficult to carry out in diagnostic laboratories with insufficient instruments or cell culture systems. An alternative assay that is easily conducted and time efficient is required. In this study, we improved the indirect enzyme-linked immunosorbent assay (I-ELISA) with clarified antigen for the detection of JEV antibodies. The I-ELISA results obtained from 175 swine serum samples were compared with HI, VN, and $PRNT_{90}$ results. The sensitivity of I-ELISA was 91.8%, 95.0%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. The specificity of I-ELISA was 92.2%, 94.7%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. Moreover, the I-ELISA results were significantly correlated with the HI (r = 0.93), VN (r = 0.95), and $PRNT_{90}$ (r = 0.92) results. These results suggest that the improved I-ELISA is useful for serosurveillance of JEV in swine.

• Korean Journal of Veterinary Research
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• v.58 no.4
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• pp.201-209
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• 2018

Canine mammary tumors are among the most frequently observed cutaneous tumors in female dogs. Cancer stem cells (CSCs), referred to as tumor-initiating cells, are thought to have properties similar to normal stem cells such as the ability to self-renewal and to differentiate into various cell types. Biological understanding of CSCs and the critical pathways involved in their maintenance are important in research and therapy for mammary tumors. We conducted the present study on sphere formation from REM134 cells by using methylcellulose to produce tumorspheres on a large scale and compared the specific markers of the spheres-formed and plating-cultured REM134 cells. The results revealed that the tumorspheres cultured in methylcellulose had higher seeding density and improved morphology compared to those produced in normal sphere formation medium. Expression levels of stemness markers and CSC-related markers were higher in tumorsphere-forming cells than in plating-cultured cells. Subsequently, we transplanted the tumorsphere-forming and plating-cultured cells into female nude mice to examine their tumorigenic potential. Tumor volume increased rapidly in mice transplanted with tumorsphere-derived cells compared to plating-cultured cells. We observed a novel sphere-forming condition for REM134 cells and showed that REM134 cell tumorspheres can exhibit improved CSC properties.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.63.1-63.9
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• 2020

Background: Canine adenovirus type 2 (CAV-2) induces infectious laryngotracheitis in members of the family Canidae, including dogs. To date, no ELISA kits specific for CAV-2 antibody have been commercialized for dogs in Korea. Objectives: We aimed to develop new indirect enzyme-linked immunosorbent assay (I-ELISA) to perform rapid, accurate serological surveys of CAV-2 in dog serum samples. Methods: In total, 165 serum samples were collected from dogs residing in Chungbuk and Gyeongbuk provinces between 2016 and 2018. The Korean CAV-2, named the APQA1701-40P strain, was propagated in Madin-Darby canine kidney cells and purified in an anion-exchange chromatography column for use as an antigen for I-ELISA. The virus-neutralizing antibody titers of CAV-2 in the dog sera were measured by virus neutralization (VN) test. Results: We compared the results obtained between the VN and new I-ELISA tests. The sensitivity, specificity, and accuracy of new I-ELISA were 98.6%, 86.4% and 97.0% compared with VN test, respectively. New I-ELISA was significantly correlated with VN (r = 0.91). Conclusions: These results indicate that new I-ELISA is useful for sero-surveillance of CAV-2 in dog serum.

• Korean Journal of Veterinary Research
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• v.63 no.1
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• pp.5.1-5.9
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• 2023

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, feline rehydragel-adjuvanted vaccine (FRAV) and feline cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

• Korean Journal of Veterinary Research
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• v.63 no.2
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• pp.13.1-13.6
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• 2023

Animals imported from abroad are a cause of rabies outbreaks in many countries. Therefore, rabies serology testing for dogs and cats traveling abroad is an important measure to reduce the incidence of rabies. Rabies virus antibodies were measured in sera collected from 2,367 dogs and 894 cats between 2017 and 2021. A serum sample with a value of 0.5 IU/mL or higher was considered a pass. The overall pass rates for rabies virus were 96.4% in dogs and 98.4% in cats. The mean rabies virus neutralization assay titers were higher in cats than in dogs and in female than in male animals. According to age, 6-year-old dogs and 9-year-old cats had the highest virus neutralization assay titers. Of the failure cases, 53.0% (53/100) were dogs or cats less than 1 year old. Although the average failure rates in dogs and cats were low at 3.5% and 1.6%, respectively, the factors influencing failure were age and vaccine manufacturer. Therefore, it is necessary to observe the vaccination interval and timing of blood collection after boosting.

• Korean Journal of Veterinary Research
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• v.63 no.2
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• pp.19.1-19.6
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• 2023

Rapid immunochromatography test (RICT) kits are commonly used for the diagnosis of canine parvovirus (CPV) because of their rapid turnaround time, simplicity, and ease of use. However, the potential for cross-reactivity and low sensitivity can yield false-positive or false-negative results. There are 4 genotypes of CPV. Therefore, evaluating the performance and reliability of RICT kits for CPV detection is essential to ensure accurate diagnosis for appropriate treatment. In this study, we evaluated the performance of commercial RICT kits in the diagnosis of all CPV genotypes. The cross-reactivity of 6 commercial RICT kits was evaluated using 8 dog-related viruses and 4 bacterial strains. The limit of detection (LOD) was measured for the 4 genotypes of CPV and feline panleukopenia virus. The tested kits showed no cross-reactivity with the 8 dog-related viruses or 4 bacteria. Most RICT kits showed strong positive results for CPV-2 variants (CPV-2a, CPV-2b, and CPV-2c). However, the 2 kits produced negative results for CPV-2 or CPV-2b at a titer of 10⁵ FAID₅₀/mL, which may result in inaccurate diagnoses. Therefore, some kits need to improve their LOD by increasing their binding efficiency to detect all CPV genotypes.

• Korean Journal of Psychosomatic Medicine
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• v.6 no.1
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• pp.35-45
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• 1998

Objectives : The purpose of this study was to determine correlation between coping strategies to disease and quality of life in chrome viral B hepatitis patients ; to investigate difference of coping strategies to disease and quality in life between chronic viral B hepatitis patients and normal persons ; and to identify major variables related to quality in life of chronic viral B hepatitis patients. Methods: The authors used Weisman coping strategy scale for measuring coping ability and efficacies, and the questionnaire for measuring quality of life including physical, psychological, social and economical aspects and satisfaction of sexual life was made by authors based on related literatures. Data were collected through questionnaire survey over a period from Sep 15, 1994 to Nov 11, 1994. Subjects served for this study consisted of 94 chronic viral B hepatitis patients visited to department of internal medicine at one general hospital and 100 normal persons visited to one general hospital for routine check up of health. The collected data were analyzed by SAS and the statistical methods for analysis were Chisquare, t-test and multiple regression analysis. Results : 1) It was revealed that coping strategies to disease significantly correlated to individual's quality of life. 2) There was no significant difference in coping strategies to disease between chronic viral B hepatitis patients and normal persons. However, chronic viral B hepatitis patients showed the lower scroes of quality of life in physical, psychological and economical aspects. 3) The most important variables which were influenced upon quality of life were coping strategies to disease and satisfaction of sexual life. That is, the more active coping strategies to diseases and the higher satisfaction of sexual life, consequently the higher quality of life was. Especially male patient group or normal persons showed each other the higher scores of quality of life in physical and psychological area than female group or patient group. 4) No statistically significant difference in coping strategies to disease and quality of life was found between HBeAg positive group and HBeAg negative group. Conclusions : The authors suggest that chronic viral B hepatitis patients may show the lower score of quality of life than normal person. Therefore, quality of life assessment should become an integral part of all clinical area that seek to assess the effectiveness of treatment. Also, through the interdisciplinary approach, a comprehensive paradigm that can better account for the effects of chronic disease on the individual' s quality of life should be developed.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.125-129
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• 1993

An acute fatal infectious disease in rabbits has been outbroken in Korea since 1985. This disease has been characterized as an acute hepatitis caused by viruses. However, viral pathogenesis in rabbit viral hepatitis leading to sudden death remain unclear. This report dealt with the electron microscopic findings on the spleen of experimentally infected rabbits, because spleen is one of the affected organs which have high titer of virus by a haemagglutination test. A typical crystalline array of virus was not found in the splenic cells of infected rabbits with acute hepatitis. Virus-like particles were seen within the phagosome of macrophages of the spleen. Ultrastructural changes in the spleen were severe with the lapse of time after inoculation. From these results, virus-like particles in the spleen were supposed to be phagocytosed by macrophage during viremia, while active replication of virus occurred in the liver. It was concluded that sudden death in this viral disease was caused by hepatic coma and/or circulatory disturbance.

• Korean Journal of Veterinary Research
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• v.60 no.3
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• pp.183-186
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• 2020

This paper describes the development of neurological signs of two prematurely born calves four days after birth. The pathological examination results indicated fibrinopurulent polyserositis, including meningoencephalitis with suppurative bronchopneumonia. Bovine viral diarrhea virus subtype 2a was detected in most of the internal organs, and the bacterial colonies cultured from the samples were identified as Klebsiella (K.) pneumoniae. Molecular analysis via multilocus sequence typing identified a different K. pneumoniae isolate in each calf-type 14 in calf A and type 65 in calf B. This is the first report identifying K. pneumoniae sequence types 14 and 65 in cattle.