• Journal of Microbiology and Biotechnology
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• v.8 no.4
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• pp.369-377
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• 1998

Rotavirus is a major cause of severe gastroenteritis in young children and animals throughout the world. The VP7 of rotavirus is thought to induce the synthesis of neutralizing antibodies and to be responsible for determining viral serotypes. The cDNA coding for the VP7 capsid protein of human rotavirus, obtained from Korean patients (HRV-Y14), was cloned and its nucleotide sequence was determined. Comparative analysis of the nucleotide sequences between VP7 of Y14 and that of other foreign isolates showed $92.7~95.2\%$ homology to G1 serotypes (RV-4, KU, K8, WA), $74.2\%$ homolgy to G2 serotype HU-5, $76.4\%$ homology to G3 serotype SA-11, and $77.6\%$ homology to G4 serotype A01321. These data suggest that HRV-Y14 can be classified as a G1 serotype. cDNA coding for VP7 of HRV-YI4 was subcloned into the baculovirus vector and the VP7 glycoprotein was expressed in insect cells. The expressed proteins in Sf9 cell extract and tissue culture fluid were separated on SDS-PAGE, and Western blot analysis with monoclonal antibody raised against the synthetic peptide containing 21 amino acids within the VP7 conserved region was performed. The molecular weight of recombinant VP7 was estimated to be 36 kDa which is about the same size as the native VP7. Addition of tunicamycin in the culture media caused a reduction of the molecular weight of the recombinant VP7 indicating that the expressed protein was glycosylated.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.485-498
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• 1994

Porphyromonas endodontalis is a black-pigmented anaerobic Gram-negative rod which is associated with endodontal infections and this microorganism possesses a potential for pathogenicity. The purpose of this study was to compare the membrane components of Porphyromonas endodontalis and Porphyromonas gingivalis and to study the immune reaction patterns of Porphyromonas endodontalis with patients with periapical lesion. Porphyromonas endodontalis (ATCC 35406), Porphyromonas gingivals serotypea (381), serotype b(W50), serotype c(A7A1-28) were cultured in anaerobic condition. Rabbit antisera were prepared by intravenous injection of formalized whole cells and human sera were obtained from patients and dental students. Indirect immunofluorescence method was used to study on the cross reaction between Porphyromonas endodontalis and Porphyromonas gingivalis serotype a, b, c antigen. Total membrane protein profiles of Porphyromonas endodontalis antigen were studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis and the reactivity of antigenic components of Porphyromonas endodontalis against sera of patients and rabbit anti-Porphyromonas endodontalis antisera were assessed by Immunoblotting method. The following results were obtained : 1. Antigens of Porphyromonas endodontalis has multiple antigenic components, and both patients with periapical lesion and normal healthy individual showed immune response to this. 2. Patients group and healthy individual group showed a diversity of immune reaction pattern but they showed immune response against 43kd protein. 3. Patients with periapical lesion showed more diverse immune response than healthy individual and in some patients, much more bands appeared to lower molecular weight protein. 4. According to indirect immunofluorescence and Immunoblotting study, Porphyromonas endodontalis did not share common antigen with Porphyromonas gingivalis serotype a, b, c.

• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.1-15
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• 1993

P. gingivalis has been implicated as a strong pathogen in periodontal disease and known to have three serotypes of P. gingivalis. The purpose of this study is to investigate on the relationship between virulence, metabolic acids and genetic heterogeneity of P. gingivalis. P. gingivalis W50 standard strain and five strains of P. gingivalis serotype b Korean isolates were used in this study. For in vitro virulence test, lyophilized whole cell P. gingivalis were suspended, and sonicated with ultrasonic dismembranometer. Sonicated samples were applied to cultured cells derived from periodontal ligament, and cell activity was assayed with growth and survival assay. The metabolic acids were also extracted, and determined by High Performance Liquid Chromatography. Pst I-digested bacterial genomic DNA was electrophoresed, and densitometric analysis was performed to study the genetic heterogeneity. All of the P. gingivalis serotype b produced butyric acid. In cell activity study, butyric acid inhibited the cell activity irrespective of its concentration. Densitometric analysis showed restriction fragment length polymorphism. These results suggested that there existed heterogeneity of the metabolic acids and the virulence of P. gingivalis and such heterogeneity might be related to genetic heterogeneity.

• Clinical and Experimental Pediatrics
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• v.55 no.3
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• pp.77-82
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• 2012

Human astrovirus (HAstV) is a major cause of acute diarrhea among children, resulting in outbreaks of diarrhea and occasionally hospitalization. Improved surveillance and application of sensitive molecular diagnostics have further defined the impact of HAstV infections in children. These studies have shown that HAstV infections are clinically milder (diarrhea, vomiting, fever) than infections with other enteric agents. Among the 8 serotypes of HAstV identified, serotype 1 is the predominant strain worldwide. In addition to serotype 1, the detection rate of HAstV types 2 to 8 has increased by using newly developed assays. HAstV is less common compared with other major gastroenteritis viruses, including norovirus and rotavirus; however, it is a potentially important viral etiological agent with a significant role in acute gastroenteritis. A better understanding of the molecular epidemiology and characteristics of HAstV strains may be valuable to develop specific prevention strategies.

• Korean Journal of Veterinary Research
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• v.31 no.3
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• pp.279-284
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• 1991

To investigate the epidemiological aspects of listeriosis, serotypes of L monocytogenes and antimicrobial susceptibilities of Listeria spp isolated from chicken carcases and chicken slaughter house environmental specimens were determined. Of 28 L monocytogenes strains, 12 strains(42.9%) were serotype 4, and the remaining 16 strains were untypable. Peak distributions of minimum inhibitory concentration$({\mu}g/ml)$ of the isolates were $0.78{\mu}g/ml$ for ampicillin, $0.39{\mu}g/ml$ for erythromycin and penicillin G, $1.56{\mu}g/ml$ for tetracycline and $6.25{\mu}g/ml$ or $12.5{\mu}g/ml$ for chloramphenicol, and $3.13{\mu}g/ml$ to > $100{\mu}g/ml$ for kanamycin and neomycin. Most of 214 isolates were sensitive to ampicillin and erythromycin, but 20. 1~78. 0% of the strains were resistant to tetracycline, kanamycin, penicillin-G and neomycin. Single or double drug resistance were observed in 75.8% of the resistant strains. The most common resistance patterns were Nm P-G(37.4%) in double pattern and P-G(23.7%) in single pattern.

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.289-299
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• 2000

The study was performed to investigate the distributions of swine pleuropneumonia in Kyongbuk western area by the enzyme-linked immunosorbent assay (ELISA). Sera collected from 400 slaughtered pigs in 3 slaughter houses during the period from May 1999 to october 1999 were tested to detect antibodies against A pleuropneumonie serotype 2 and 5. The optimal dilution of CBE antigen, conjugate and serum for this ELISA were determined 1 : 400, 1 : 20,000, 1 100, respectively. The optimal dilution of OW antigen, conjugate and serum for this ELISA were determined 1 : In, 1 : 20,000, 1 : 200, respectively. Cut-off value in this ELISA was determined by mean absorbance (at 492 nm) of negative control sera added with the triple value of the standard deviation. Cut-off value in ELISA by CBE and OMP antigen were 1.134 and 1.217, respectively. By the ELISA, positive reaction rates to A pleuropneumoniae serotype 2 and 5 for CBE antigen were 38.8% and 18.8%, and for OMP antigen were 42.8% and 23.5% of the 400 samples, respectively.

• Journal of Veterinary Science
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• v.24 no.3
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• pp.40.1-40.6
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• 2023

Analysis of the VP1 gene sequence of the foot and mouth disease virus (FMDV) is critical to understanding viral evolution and disease epidemiology. A standard set of primers have been used for the detection and sequence analysis of the VP1 gene of FMDV directly from suspected clinical samples with limited success. The study validated VP1-specific degenerate primer-based reverse transcription polymerase chain reaction (RT-PCR) for the qualitative detection and sequencing of serotype O FMDV lineages circulating in India. The novel degenerate primer-based RT-PCR amplifying the VP1 gene can circumvent the genetic heterogeneity observed in viruses after cell culture adaptation and facilitate precise viral gene sequence analysis from clinical samples.

• Korean Journal of Veterinary Service
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• v.14 no.2
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• pp.127-133
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• 1991

The present study was conducted to investigate the biochemical properties, pathogenicity, antimicrobial test, and serotype of E-coli isolated from slaughtered cattle during the period from March 1991 to May 1991. 1. A total of 12 E-coli isolates were isolated from 132 bile juice of slaughtered cattle. 2. All isolates were resistant to Erythromycin, Cephalothin, Neomycin and Lincomycin while the majority of them were susceptible to Trimethoprimsulfamethoxazol (67%), Chloramphenicol(58％), Gentamicin(58%), Ampicillin(17%), Kanamycin(9%) and Tetracycline (9%). 3. In the test of colicinogenecity and congo-red binding capability, 4(33%) isolates produced colicin, all isolates were congo-red negative. 4. The serotypes of isolated E-coli were identified as 008： K- (2 strain), 015： K- (1 strain), 08： K87： K88ab(1 strain), 0139： Kl2(1 strain), 0147: K89(1 strain), others(6 strains ) were autoagglutination.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.1
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• pp.26-32
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• 2001

독소원성 대장균(enterotoxigenic Escherichia coli, ETEC, EC81, serotype O148:H28)이 생산하는 heat labile enterotoxin(LT)를 검색해 본 결과, reversed passive latex agglutination(RPLA)법에 있어서는 2배로 희석한 용액 (50 ng)으로부터 64로 희석한 용액 (1.56 ng)에서까지 양성반응을 보였으며 polymerase chain reaction (PCR)기법에 있어서는 10 ng으로부터 1 pg희석용액에서까지 147-base pair(bp)의 LT DNA fragment가 확인되었다. Clostridium perfringens A형 (NCTC8238, Hobbs serotype 2)이 생산한는 장독소를 검색해 본 결과, RPLA법에 있어서는 2배로 희석한 용액 (50 ng)으로부터 64로 희석한 용액 (1.56 ng)에서 까지 양성반응을 보여 독소원성대장균이 생산하는 LT와 일치하였으나, PCR기법에 있어서는 10ng로부터 10 pg 희석용액에서 까지 354-bp의 DNA fragment가 확인되어 독소원성대장균이 생산하는 LT보다 1/10의 낮은 감도를 보였다. PCR기법은 RPLA법에 비하여 훨씬 신속하고 소량의 sample로 장독소를 확인할 수 있었다.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.508-511
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• 2009

Streptococcus pneumoniae is a major cause of serious invasive diseases in children, especially in young infants, but seven- valent pneumococcal conjugate vaccine (PCV7) is believed to prevent invasive pneumococcal pneumonia and meningitis in young children. However, recently, the incidence of non-PCV7 serotype has increased after PCV7 vaccination. A 14-month- old female patient presented at our emergency room with mental change and lethargy. Three days previously, she had developed fever and vomiting. After being admitted, she rapidly progressed to coma and brain death despite prompt and extensive supportive treatment. She expired 20 days after admission with a final diagnosis of pneumococcal 19A (non-PCV7 serotype) meningoencephalitis despite having received PCV7 ($Prevenar^{(R)}$) vaccinations on three occasions. The author reports this first fatality due to pneumococcal 19A meningoencephalitis in Korea and provides a brief review of the literature.