• Korean Journal of Veterinary Research
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• v.56 no.1
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• pp.37-40
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• 2016

A total of 131 Pasteurella (P.) multocida strains were isolated from the lungs of 1,064 pigs with respiratory clinical signs nationwide during 2009-2010 and 2013-2014. The strains of P. multocida comprised 77.1% serotype A and 22.9% serotype D. Analysis of a recent P. multocida outbreak in Korean pigs showed that the isolation rate of serotype D decreased annually. The incidence of antimicrobial resistance, as measured using minimal inhibitory concentration values, has decreased recently. Overall, further studies to characterize P. multocida isolated from pigs in Korea are needed to prevent P. multocida infection in the Korean swine industry

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.181-186
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• 1996

The present study was conducted to investigate the biochemical and serologic characteristic of Actinobacillus pleuropneumoniae isolated from pneumonic lungs of pigs during the period from January 1992 to April 1993. A pleuropneumoniae was isolated from 17(27.0%) of 63 growing pigs with respiratory signs and 21(6.4%) of 330 pneumonic lungs of slaughtered pigs. The seasonal isolation frequency of A pleuropneumoniae was higher in winter and spring than that in summer or fall. The biochemical and cultural properties of A pleluropneumoniae isolated from the pneumonic lungs of pigs were identical to those of the reference strains used. The isolates were highly susceptible to ampicillin, cephalothin, ceftiofur, ciprofloxacin(MIC : ${\leq}0.39{\mu}g/ml$) and moderately susceptible to amikacin, chloramphenicol, erythromycin, kanamycin, methicillin, penicillin-G, streptomycin(MIC : 0.78~25IU or ${\mu}g/ml$), respectively. Sulfadimethoxine, sulfamerazine, tylosine showed no response to the isolates(MIC : ${\geq}100{\mu}g/ml$). Among the 38 isolates, 21(55.3%) and 13(34.2%) were resistant to oxytetracycline aid lincomydn, respectively(MIC : ${\geq}50IU$ or ${\mu}g/ml$). The majority of 38 A pleuropneumoniae isolates were turned out as serotype 2(47.4%) or serotype 5(54.7%) and the remaining 3 isolates were evenly classified to serotype 7, 10 or 12. It was noted A pleuropneumonine serotype 5 isolates were more resistant to oxytetracycline than serotype 2 isolates.

• Biomedical Science Letters
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• v.24 no.3
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• pp.183-195
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• 2018

Cryptococcosis, which is caused by the Cryptococcus species complex (including Cryptococcus neoformans and Cryptococcus gattii), is well known as one of the most important medical problems. However, the of the Cryptococcus species complex is still limited to pneumonia and meningitis. In particular, the differences in virulence among the five major serotypes of the Cryptococcus species complex are not fully understood. To elucidate the virulence of the Cryptococcus species complex when it is disseminated hematogenously, rats were infected by different strains of the Cryptococcus species serotype, and their histopathological characteristics were compared after infection. The cumulative mortality ratio of rats infected with serotype B strain was slightly higher than in the other experimental groups. In addition, the average recovery of the Cryptococcus species complex from rats infected with serotype B strain was significantly higher than in the other groups in almost all organ samples except spleen. The recovery of the Cryptococcus species complex was associated with the severity of histopathological lesions, including bleeding, inflammation, and tissue damage in all organs. In rats infected with serotype B strain, the virulence was the most severe, especially in the lungs and liver. These results indicate that the pathophysiology of the Cryptococcus species complex infection differs according to serotype.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.506-511
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• 2005

Purpose : Streptococcus pneumoniae serotype 6B and 6A are important pathogens in pneumococcal infections. It is commonly assumed that the 6B vaccines elicit antibodies cross-reacting with the 6A serotype and the cross-reactive antibodies protect against infections of 6A. To examine this assumption, we measured the opsonophagocytic capacity to serotype 6A and 6B in adults. Methods : Twenty-four adults were immunized with pneumococcal PS vaccine that contains 6B PS. Their preimmune and postimmune sera were studied for the capacity to opsonize 6B and 6A serotypes with opsonophagocytic killing assay. Results : Opsonization titers to 6B were significantly higher than those to 6A in preimmune and postimmune sera. Because significant increasesof opsonization titers were observed in adults with polysaccharide vaccines for 6A(cross-reactive) serotype as well as for 6B(vaccine) serotype, 6B PS in vaccine elicited cross-protective antibodies to 6A, but not in all cases. One adult did not have detectable levels of opsonization titers to 6A after immunization. Conclusion : Although 6B PS in pneumococcal PS vaccine elicits antibodies cross-reacting with 6A serotype in some adults, it may not occur always. This study should be extended to other age groups such as children and elderly people. The presence of the cross-protection should be directly determined in clinical trials of the pneumococcal vaccines as well as during the postlicensure monitoring surveys by serotyping the clinical isolates of pneumococci.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.221-227
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• 2008

Bordetella pertussis is pathogenic bacteria causing pertussis, a infectious respiratory disease for the infants. The incidence rate of pertussis was significantly decreased after introduction of vaccine. However, increased pertussis cases are recently reported in several countries with high vaccine coverage. One of the inferred reasons is genotype or serotype variation between circulating strains and vaccine strains. Therefore, it is required to confirm the variation status of the isolates by genotype or serotype analysis and the possibility of pertussis outbreak in Korea should be estimated. For this, the serotype variations of the isolates from $1999\sim2006$ were investigated in agglutinogen and fimbriae. As the result, the most frequent serotype in the isolated strains was agglutinogen 1 and fimbriae 2 serotypes. Moreover, serotype transition from vaccine serotypes to non-vaccine serotypes was observed. Especially, the transition pattern of agglutinogen serotype was directed to increase a different type (agg 1) from the vaccine type (agg 1,2). However, in case of fimbriae, the same type (fim 2) with vaccine strain was increased. These results were also observed in other countries with increasing incidence of pertussis. For more predictable results to know increasing possibility of pertussis incidence in Korea, the studies on genetic variations of antigenic determinant genes and prevalence of antibody titer in normal population should be performed in the further.

• Journal of Life Science
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• v.14 no.4
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• pp.620-626
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• 2004

Viruses causing acute conjuntivitis were isolated from 675 patients carrying eye infections for year 2001 to 2003 in Busan reagion and their antigenic properties characterized by a serological survey. In 2001, adenoviruses (serotype 8) were found in 5 of 48 cases. In 2002, the isolated viruses were 7 adenoviruses (serotype 8 and 37), 8 coxsakieviruses (serotype A24 and B3) and 1 echoviruses (serotype 6) from 324 specimens that are known as the causative agents of acute hemorrhagic conjuctivitis (AHC). In 2003, 25 case of 303 specimens were 7 adenoviruses (serotype 3, 4, 8 and 37), 7 echoviruses (serotype 6 and 7) and 4 untypable enteroviruses. Although coxsakievirus (serotype B3) and echoviruses (serotype 6 and 7) were generally known as causative agent of aseptic meningitis, it hasn't been reported until now that they were isolated from the conjunctival swabs. The out break of AC was observed from April to October in Busan. These isolated viruses showed a strong cytophatic effects on HEp-2, RD, Vero and BGM cell strains. Analysis of electron micrograph of those viruses showed that adenovirus consists of a 80 nm diameter and nonenvloped icosahedron and then echovirus and coxsackievirus were small nonenveloped and isometric-shaped viruses. Adenovirus showing a cytophatic effect was resulted in a 458 bp single band by PCR and echovirus, coxsackievirus and untypable enterovirus were detected a 437 bp products by RT-PCR.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.47-54
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• 1980

Exoenzymes, protease(P) and elastase(E) produced by Pseudomonas aeruginosa are reported to have close relationship with pathogenicity of Pseudomonas aeruginosa. Productibility of exoenzymes P and E were studied and compared in environmental isolates from hospital environments and clinical isolates from various clinical specimens, also, the relationship between their enzyme production and serotype were reviewed. 1. Clinical isolates were typed into nine serotypes A, B, C, D, E, F, G, H and I. Serotype E had the highest incidence of 24%, followed by B with 16.8%, G, 15.1% and C, 9.3%. 2. Environmental isolates were, typed as serotype B, C, E, F, G, H, I, K and M. Serotype I had the highest incidence of 26.6%, followed by C, F and M each incidence of 14.3%. 3. In the typing of the above two groups, serotypes A and D were found only in the clinical isolates and serotypes K, and M were found only in the environmental isolates. Serotypes J and L were found in neither clinical isolates nor environmental isolates. 4. In the distribution of serotypes from various clinical specimens, serotype G among isolates from pus showed incidence of 20.4%, and serotypes E and B were 19.5% separately. Serotype E had incidence of 22.6% and 20.0% in urine and sputa respectively, showing a high rate compared to the other serotypes. 5. The incidence of strains producing both exoenzymes P and E was 77.8% in the preserved strains of clinical isolates and 76.2% in the environmental isolates. There were no significant difference between the two groups. 6. Serotypes A and H, which are preserved strains from clinical isolates showed productibility of both exoenzymes P and E, the other serotypes showed productibility of various combination of exoenzymes. Among the environmental isoaltes, production of both exoenzymes P and E were seen in serotypes E, F, G, H, I and K and no serotype produced only P or E. 7. In ability to produce exoenzymes of isolates from sources of various clinical specimens, strains producing both exoenzymes P and E were found most frequently in pus with incidence rate of 82.0%, followed by 80.0% in sputum and urine. 8. Almost all the fresh strains of clinical isolates were producers of both exoenzymes P and E.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.41-46
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• 2000

Purpose: It is important to have the epidemiologic data of rotavirus serotypes for the application of polyvalent rotavirus vaccines. Epidemiological studies of rotavirus serotypes in Korea have been reported only in limited areas with small number of cases. Authors tried to investigate the distribution of rotavirus G serotypes in ChungJu area with RT-PCR. Method: Stool specimens were collected from 202 children with acute diarrheal symptoms, who admitted to or visited Kon-Kuk University Hospital in ChungJu from June 1998 to May 1999. Samples were screened for rotavirus with EIA method (TestPack Rotavirus, Abbott Laboratories) and rotavirus G Serotypes were determined by RT-PCR. Results: Rotavirus was positive in 46.6%. The incidence of G serotypes was as follows; G1 10%, G2 10%, G3 28%, G4 26%, and G9 20%. There were three cases of multiple serotypes; G1 with G9, G2 with G9, and G4 with G9. Serotype of G8 was not found. Conclusion: The proportion of G serotypes in ChungJu is much different from previous reports. Serotype of G9 was found which had not been reported in Korean children till now. Long term plans for the investigation of rotavirus serotypes must be needed in wide area.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.257-264
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• 2006

Fifty eight Cryptococcus neoformans strains isolated from clinical and environmental sources in Korea were examined for their serotypes and extracellular enzyme activities. Among the 51 strains isolated from clinical sources, 48 strains were serotype A (94.1%), 2 strains were serotype B (3.92%), and 1 strain was serotype D (1.96%). All seven environmental strains isolated from pigeon excreta were identified as serotype A. All isolates of C. neoformtans were positive for the production of extracellular proteinase and phospholipase. In the API-ZYM system, all fifty eight isolates produced alkaine phosphatase, esterase C4, esterase lipase: C8, leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrase, $\alpha$-glucosidase and $\beta$-glucosidase. Thirty nine isolates (67.2%) of C. neoformans produced N-acetyl-$\beta$-glucosidase. Two isolates, serotype B, and B only one serotype A produced $\beta$-glucuronidase. Analysis of enzymatic profiles to 21 enzymes revealed four biotypic patterns among the 58 strains. The enzymatic patterns of C. neoformans isolated from clinical and environmental sources represented a significant relationship with the serotypes.

• Biomedical Science Letters
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• v.9 no.4
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• pp.209-214
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• 2003

To determine the clinical usefulness of Immuno Blot test, 160 samples from the patients with chronic HCV infection were analyzed. And serotyping and line probe assay were performed to evaluate the distribution of hepatitis C virus genotypes in Korean isolates. In this group, as a result of genotyping type 1 band 2a, the serotype I and II were the most common source of HCV infection. There were no significant difference in response to the alpha-interferon HCV infection treatment with the subtype 1 b or 2a. And the serotypes of NS4 peptides were compared with the genotypes to evaluate their clinical usefulness. Among 49 cases studied for genotypes and serotype, genotype 1 b, 1 b/2b, 2a, 2a/2c and 2b were 51.0％, 2.0％, 34.6％, 8.1％ and 4.0％, respectively. The serotypes I and II were 57.1％ and 42.8％, respectively; they were matched with genotypes in 85.7％ and seemed to be easy to perform. To monitor their performing progress or treatment response, serotype test was made before the genotype test. The Result showed that there was no significant difference in response to the alpha-interferon HCV infection treatment with the subtype 1 b or 2a in Korea.