• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.49-57
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• 1997

We developed a sensitive, nested reverse transcription-polymerase chain reaction (RT-PCR) to detect Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in animal tissues. Total RNA was extracted from blood, lung or kidney samples of experimentally-infected hamsters by using the guanidine isothiocyanate buffer-acid phenol-chloroform method. Genus-reactive outer primers were derived from the consensus region of the G1 gene sequences of several hantaviruses. Serotype-specific primers were selected within the region amplified by the outer primers. To examine the sensitivity and specificity of the test, we diluted known quantities of Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in human or hamster immune sera before performing the nested RT-PCR. We could detect as little as 1 pfu of virus, even in the presence of high-titer neutralizing antibodies, and the serotype-specific primers amplified only homologous serotype viruses. RT-PCR with these primers demonstrated virus in the blood of experimentally-infected hamsters as early as four days to as late as 30 days after infection. A comparison of a standard immunofluorescent antibody screening test (IFAT) to nested RT-PCR with RNA extracted from lung or kidney tissues of the hamsters, demonstrated that RT-PCR to be more sensitive for identifying viruses in these tissues.

• Korean Journal of Veterinary Service
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• v.35 no.1
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• pp.19-24
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• 2012

This study was performed to evaluate the prevalence rate of Toxoplasma gondii on 217 stray cats in Daejeon. The positive infection rate of T. gondii was 15.7% in enzyme-linked immunosorbent assay (ELISA), 12.4% in latex agglutination test (LAT), 14.7% in indirect immunofluorescent antibody test (IFA) and 0.5% in polymerase chain reaction (PCR) respectively. In districts, Yuseong-gu was shown the highest seropositive rate of T. gondii as 31.8% in ELISA, 22.7% in LAT and 31.8% in IFA. In gender, the seropositive rate of female cats was slightly higher than that of male cats as 17.2% in ELISA, 15.2% in LAT, 15.2% in IFA and 1.0% in PCR. Cats captured in National science museum, detached house and apartment was shown relatively high prevalence rate of T. gondii.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.59-65
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• 1996

For easy and rapid screening of hemorrhagic fever with renal syndrome (HFRS) without any laboratory equipment, dot blot enzyme immunoassay was developed and tried to detect anti-hantavirus antibodies. The nucleocapsid protein of Hantaan virus was isolated by affinity chromatography and used for making the dot strip. 28 of 29 Hantaan virus infected sera showed positive signals and 21 of 22 HFRS negative sera showed no positive signals. Anti-Seoul virus monoclonal antibody also exibited positive signal but the intensity of colorization was approximately 5 fold less than that of anti-Hantaan monoclonal antibody. The sensitivity of dot blot assay was equal or superior to indirect immunofluorescent assay (IFA) or ELISA test. Overall, the screening results with dot blot assay showed 92.2 % of concordance with IFA or ELISA test. This results suggests that dot blot assay could be applied a tool for easy and rapid screening of HFRS.

• Parasites, Hosts and Diseases
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• v.35 no.4
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• pp.291-294
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• 1997

On July and August 1997 two 15-year-old mates of a football team of Tongjin Middle School in northern Kyon99i-do, Korea were consecutively diagnosed as vivax malaria by peripheral blood smear. They had no histories of travelling abroad or drug abuse. Thry witnessed that othev mates in the tram were ill of fever in the same period. A small survey was therefore undertaken to determine whether vivax malaria was outbroken locally. A total of 57 students of the team living together in a dormitory was examined for history of fever. presence of splenomegaly, blood smear and anti-p. uiuax antibody test by immunofluorescent antibody test (IFAT) . Except for the above two patients, only one case rrvraled a marginal tiler of IFAT. No other positive findings of vivax malaria were found. In the results of this local survey. no move cases of vivax malaria were revealed except the two sporadic cases.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.82-82
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• 1997

The hepatitis B virus(HBV) is a small, enveloped virus with a circular, double-stranded DNA genome. HBV causes active and chronic hepatitis worldwide, including Korea, and is considered to be a major factor for liver cirrhosis and hepatocellular carcinoma. In contrast to the wealth of knowledge on the gene structure and expressional regulation, immunological and pathological mechanisms for HBV-induced hepatocellular injury are not well known. In the present study, vaccinia virus which has been demonstrated to be a useful eukaryotic expression vector was used to clone the gene for HBV surface antigen, L(S+preS2+preS1). The recombinant vaccinia virus vector, pMJ-L, which contains L surface antigen gene of adr-type HBV was constructed, and subseouently used for making recombinant vaccinia virus VV-$\textrm{HBV}_{L}$. Expression of the HBV antigen was examined by immunofluorescent antibody (IFA) test using mouse monoclonal anti-hepatitis B surface antigen. HBsAg was detected in the recombinant virus indicating that the VV-$\textrm{HBV}_{L}$ expressed S antigen successfully. The HBV-Vaccinia Virus recombinant obtained in this study is currently being used for studying the immunological aspects of HBV infection.

• The Journal of Korean Society of Virology
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• v.28 no.4
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• pp.377-382
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• 1998

Hemorrhagic fever with renal syndrome (HFRS), scrub typhus, murine typhus and leptospirosis have been the principal acute febrile diseases in Korea. To evaluate the seroepidemiologic patterns of acute febrile illness, sera collected from 2,423 patients in 1996 were examined for antibodies against Hantaan virus, Orientia tsutsugamushi, Rickettsia typhi, and Borrelia burgdorferi by indirect immunofluorescent antibody technique (IFA) and macroscopic agglutination test for Leptospira interogans. Seropositive cases against Otsutsugamushi, Rickettsia typhi, Leptospira interogans and Hantaan virus were 192 (7.9%), 193 (8.0%), 12 (0.5%) and 324 (13.4%), respectively. Male was more affected in HFRS and murine typhus contrasting to scrub typhus and leptospirosis in female. Most positive cases occurred during October and November for scrub typhus, and during November and December for HFRS. These results showed similar patterns with previous epidemical data for recent couple of years, and possibly implied no significant changes occurred in ecologic situations for acute febrile diseases in Korea.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.61-68
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• 2000

Among wild chipmunks, Tamias sibiricus, captured in Kyunggi and Kangwon province in Korea, 1997, seropositivity for Orientia tsutsugamushi was determined. Serological test for Orientia tsutsugamushi infection was performed using indirect immunofluorescent antibody technique (IFA). Of 243 wild chipmunks, 61 against Gilliam strain and 64 against Karp strain of Orientia tsutsugamushi were IFA positive. Seropositivity against Gilliam strain was shown 33.3% in Kyunggi and 23.5% in Kangwon province, and against Karp strain was shown 33.3% and 25.4%, respectively.

• Korean Journal of Veterinary Pathology
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• v.1 no.2
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• pp.125-134
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• 1997

Porcine Reproductive and Respiratory Syndrome Virus infection (PRRSV) was confirmed by serology histopathology immunohistochemistry and bacteriologic examination in young pigs. Four suckling and six weaned piglets submitted from three different farms showed coughing sneezing labored rapid abdominal respiration lethargy and anorexia. Grossly apical and cardiac lung lobes appeared mottled with pale to dark tan discoloration. Submandibular and bronchial lymph nodes were tan and enlarged. All piglets were seropositive for PRRSV antibodies by the indirect immunofluorescent antibody(IFA) test. Microscopically lung lesions were characterized by hyperplasia and hypertrophy of type 2 pneumocytes infiltration of mononuclear cells in alveolar intersitium accumulation of necrotic debris in alveolar spaces accompanied by proliferation of alveolar multinucleated syncytial cells. Using immunohistochemical technique PRRSV antigens were demonstrated in alveolar macrophages and type 2 pneumocytes in histologic lung tissue sections. Also PRRSV antigens were detected in brain lymph nodes spleen and heart. Additionally piglets showed nonsuppurative meningoencephalitis mandibular necrotic lymphadenopathy splenic atrophy and myocardial necrosis.

• Parasites, Hosts and Diseases
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• v.45 no.4
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• pp.295-299
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• 2007

The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at $4^{\circ}C$, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1:50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.859-866
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• 1998

This study was carried out to investigate the prevalence of Neopsora (N) caninum infection in Korean dairy herds. To determine the prevalence of antibodies to N caninum in Korean dairy cattle, a total of 1,688 sera including 895 sera taken from 30 herds having recent high abortion rate and 793 sera selected randomly from 168 herds with no history of recent abortion problem, respectively, collected nationwide during a designated period were analyzed by indirect fluorescent antibody (IFA) test. Mean nationwide seropositive rate of the sera tested in herds and individual cattle tested were 53.5% and 35.6%, respectively. However mean seropositive rate of the samples from herds having abortion problem was approximately two and half times higher than those in herds with no recent abortion history. Regional seropositive rates of the samples from the herds with abortion problem were 48.6%, 51.6%, 44.4% and 71.4% at Kyunggi, Kangwon, Kyungbuk and Jeonnam province, respetively. Regional seropositive rates of the samples from the herds with no recent abortion problem were 35.6%, 18.3%, 16.5%, 37.5%, 19.4%, 33.3%, 32.1%, 3.8% and 0.0% at Kyunggi, Kangwon, Chungbuk, Chungnam, Kyungbuk, Kyungnam, Jeonbuk, Jeonnam and Jeju province, respectively. The results of this study suggested that N caninum infection was widespread and considerably associated with bovine abortion in Korea.