• Food Science and Biotechnology
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• v.17 no.6
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• pp.1171-1177
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• 2008

This study was undertaken to classify Enterobacter sakazakii isolates from 13 powdered infant formula products, 25 powdered weaning diet products, and 33 weaning diet ingredients on polymerse chain reaction (PCR) methods. The numbers of the isolates from 1 powdered infant formula product, 7 powdered weaning diet products, and 6 weaning diet ingredients were 1, 14, and 8, respectively. The contaminated ingredients were 1 rice powder, 2 millet powders, 2 vegetable powders, and 1 fruit and vegetable premix. PCR with the primer of repetitive extragenic palindromic element (REP-PCR) and random amplification of polymorphic DNA(RAPD) were effective in discriminating among the isolates, but tRNA-PCR and PCR with the primer of l6S-23S internal transcribed spacer (ITS-PCR) were not. Some of E. sakazakii isolates from vegetable powders, fruit and vegetable premix, and millets powders were classified into the clonal groups based on the DNA patterns in the REP-PCR and RAPD analysis. A close genetic relationship among the isolates from some of the powdered weaning diet products and the rice powder was also detected in the cluster analysis based on the DNA patterns in RAPD.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.19-27
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• 1997

To develop the polymerase chain reaction (PCR) for the detection of type D simian retrovirus (SRV) infection, an oligonucleotide primer pair was designed to hybridize to the sequences within env gene of SRV subtype 1 (SRV-1). The 3' proximal env sequences annealing to the primers had been rather conserved among three different subtypes of SRV, SRV-1, SRV-2, and SRV-3 (Mason-Pfizer Monkey Virus: MPMV). The PCR using the primer pair targeting an env region successfully detected and amplified all three subtypes of SRV with excellent specificity after single round of reaction. The tests with peripheral blood mononuclear cells infected either with simian immunodeficiency virus or simian T-Iymphotropic virus type 1, major immunosuppressive viral agents together with SRV in simian, verified the specificity of the PCR by excluding any cross reactivity. Semiquantitative titration PCR, amplifying serially diluted plasmid DNA of each subtype, was performed to evaluate sensitivity limits of the reaction. Based on molecular weight of each cloned SRV genome, the PCR should be able to detect one SRV-infected cell per more than $5-7{\times}10^4$ uninfected cells after simple ethidium bromide staining of resulting products. The PCR must be very efficient screening system with its quickness, certainty, and sensitivity for SRV-infected animals used in human AIDS research model. Second round amplification of the reaction products from the first PCR, or Southern hybridization by radiolabeled probes shall render to compete its efficacy to ELISA which has been the most sensitive technique to screen SRV infection but with frequent ambiguity problem.

• Research in Plant Disease
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• v.23 no.4
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• pp.363-366
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• 2017

Barley mild mosaic virus (BaMMV), Barley yellow mosaic virus (BaYMV) and Barley yellow dwarf virus (BYDV) have been identified as an important causative agents for an economically important disease of winter barley in Korea. In this study, a multiplex reverse transcription polymerase chain reaction (mRT-PCR) method was used for the simultaneous detection. Three sets of virus-specific primers targeted to the capsid protein coding genes of BaMMV, BaYMV and BYDV were used to amplify fragments that were 594 bp, 461 bp, and 290 bp, respectively. Several sets of primers for each target virus were evaluated for their sensitivity and specificity by multiplex RT-PCR. The optimum primer concentrations and RT-PCR conditions were determined for the multiplex RT-PCR. The mRT-PCR assay was found to be a better and rapid virus diagnostic tool of specific barley diseases and potential for investigating the epidemiology of these viral diseases.

• Korean Journal of Veterinary Service
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• v.34 no.4
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• pp.417-428
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• 2011

Species-specific PCR assay was developed for detection of cattle, sheep, goat, horse, dog, pig, chicken, duck, goose, and turkey using mitochondrial 12S rRNA and 16S rRNA as target genes. Also, an internal positive control was used to detect possible false negatives by using 18S rRNA gene. We designed species-specific primers with amplicon length of 190, 219, 350, 467, 241, 119, 171, 229, 111 and 268 bp for cattle, sheep, goat, horse, dog, pig, chicken, duck, goose, and turkey respectively. The specificity of the primers was tested against the other 10 non-target animal species and a cross-reaction was not observed. We developed two multiplex PCR assays for the simultaneous identification of Korea's major livestock species (cattle, pig, chicken and duck) and poultry species (chicken, duck, goose and turkey) from analogous samples, retaining the same specificity. The limit of detection of the multiplex PCR assay (cattle, pig, chicken and duck) ranged between 1 pg and 0.1 pg of template DNA extracts from raw meat. Applying multiplex PCR assays to DNA extracts from experimental pork/beef and pork/chicken tested raw and heat-treated ($120^{\circ}C$ for 30 min) mixtures respectively, detection limit was 0.1% level beef in pork, pork in beef and chicken in pork and 1.0% level pork in chicken. In conclusion, this assay using gel-based capillary electrophoresis would be very useful in highly sensitive and rapid identification of animal species or ingredients in minced meat and other meat products.

• Journal of Acupuncture Research
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• v.24 no.3
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• pp.197-205
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• 2007

Objectives : Tumor necrosis factor-${\alpha}$(TNF ${\alpha}$) is a proinflammatory cytokine involved in the pathogenesis of rheumatoid arthritis. This study was designed to investigate the relation between TNF-${\alpha}$ gene polymorphism and rheumatoid arthritis in Korean population. Methods : This study was carried out on 103 rheumatoid arthritis patients who fulfilled the American College of Rheumatology 1987 revised criteria for rheumatoid arthritis and 208 healthy control subjects. Blood samples from all subjects were obtained for DNA extraction. The extracted DNA was amplified by polymerse chain reaction(PCR). PCR products were visualized by 2% agarose gel electrophoresis. We investigated the genotyping of TNF-${\alpha}$ by using Pyrosequencing. Results: The genotypes of TNF-${\alpha}$ gene were GG, AG and AA. While the distribution of TNF-${\alpha}$ polymorphism in control subjects was 92.31%, 7.21%, 0.48% respectively, in rheumatoid arthritis patients was 93.20%, 6.80%, 0.00%(GG, AG, AA). There was no statistical significant allelic frequency difference between control and rheumatoid arthritis groups. Conclusions : We concluded that there was no significant association between TNF-${\alpha}$ gene polymorphism and rheumatoid arthritis. However, the findings of this study need to be confirmed in more patients and further studies.

• Journal of Pharmacopuncture
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• v.10 no.2 s.23
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• pp.73-79
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• 2007

Objectives : Tumor necrosis factor-${\alpha}{\cdot}$(TNF-${\alpha}{\cdot}$) is a proinflammatory cytokine involved in the pathogenesis of rheumatoid arthritis. This study was designed to investigate the relation between TNF-${\alpha}{\cdot}$ gene polymorphism and rheumatoid arthritis in Korean population. Methods : This study was carried out on 103 rheumatoid arthritis patients who fulfilled the American College of Rheumatology 1987 revised criteria for rheumatoid arthritis and 208 healthy control subjects. Blood samples from all subjects were obtained for DNA extraction. The extracted DNA was amplified by polymerse chain reaction(PCR). PCR products were visualized by 2% agarose gel electrophoresis. We investigated the genotyping of TNF-${\alpha}{\cdot}$ by using Pyrosequencing. Results : The genotypes of TNF-${\alpha}{\cdot}$ gene were GG, AG and AA. While the distribution of TNF-${\alpha}{\cdot}$ polymorphism in control subjects was 92.31%, 7.21%, 0.48% respectively, in rheumatoid arthritis patients was 93.20%, 6.80%, 0.00%(GG, AG. AA). There was no statistical significant allelic frequency difference between control and rheumatoid arthritis groups. Conclusion : We concluded that there was no significant association between TNF-${\alpha}{\cdot}$ gene polymorphism and rheumatoid arthritis. However, the findings of this study need to be confirmed in more patients and further studies.