• Clinical and Experimental Pediatrics
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• 제55권11호
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• pp.424-429
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• 2012

Purpose: Methods for quick and reliable detection of Streptococcus pneumoniae are needed for the diagnosis of pneumococcal disease and vaccine studies. This study aimed to show that sequential multiplex polymerase chain reaction (PCR) is more efficient than conventional culture in achieving S. pneumoniae -positive results. Methods: Nasopharyngeal (NP) secretions were obtained from 842 pediatric patients admitted with lower respiratory infections at Severance Children's Hospital in Korea between March 2009 and June 2010. For identification and serotype determination of pneumococci from the NP secretions, the secretions were evaluated via multiplex PCR technique with 35 serotype-specific primers arranged in 8 multiplex PCR sets and conventional bacteriological culture technique. Results: Among the results for 793 samples that underwent both bacterial culture and PCR analysis for pneumococcal detection, 153 (19.3%) results obtained by PCR and 81 (10.2%) results obtained by conventional culture technique were positive for S. pneumoniae. The predominant serotypes observed, in order of decreasing frequency, were 19A (23%), 6A/B (16%), 19F (11%), 15B/C (5%), 15A (5%), and 11A (4%); further, 26% of the isolates were non-typeable. Conclusion: As opposed to conventional bacteriological tests, PCR analysis can accurately and rapidly identify pneumococcal serotypes.

• International Journal of Oral Biology
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• 제46권3호
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• pp.140-145
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• 2021

This study aimed to develop Lautropia mirabilis-specific quantitative real-time polymerase chain reaction (qPCR) primers based on the sequence of DNA-directed RNA polymerase subunit beta gene. The PrimerSelect program was used in designing of the qPCR primers, RTLam-F4 and RTLam-R3. The specificity of the qPCR primers were performed by conventional PCR with 37 strains of 37 oral bacterial species, including L. mirabilis. The sensitivity of the primers was determined by qPCR with the serial dilution of purified genomic DNA of L. mirabilis KCOM 3484, ranged from 4 ng to 4 fg. The data showed that the qPCR primers could detect only L. mirabilis strains and as little as 40 fg of genome DNA of L. mirabilis KCOM 3484. These results indicate that this qPCR primer pair (RTLam-F4/RTLam-R3) may be useful for species-specific detection of L. mirabilis in epidemiological studies of oral bacterial infectious diseases such as periodontal disease.

• Journal of Genetic Medicine
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• 제12권2호
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• pp.72-78
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• 2015

Recently, noninvasive prenatal test (NIPT) has been adopted as a primary screening tool for fetal chromosomal aneuploidy. The principle of NIPT lies in isolating the fetal fraction of cell-free DNA in maternal plasma and analyzing it with bioinformatic tools to measure the amount of gene from the target chromosome, such as chromosomes 21, 18, and 13. NIPT will contribute to decreasing the need for unnecessary invasive procedures, including amniocentesis and chorionic villi sampling, for confirming fetal aneuploidy because of its higher positive predictive value than that of the conventional prenatal screening method. However, its greater cost than that of the current antenatal screening protocol may be an obstacle to the adoption of this innovative technique in clinical practice. Digital polymerase chain reaction (dPCR) is a novel approach for detecting and quantifying nucleic acid. dPCR provides real-time diagnostic advantages with higher sensitivity, accuracy, and absolute quantification than conventional quantitative PCR. Since the groundbreaking discovery that fetal cell-free nucleic acid exists in maternal plasma was reported, dPCR has been used for the quantification of fetal DNA and for screening for fetal aneuploidy. It has been suggested that dPCR will decrease the cost by targeting specific sequences in the target chromosome, and dPCR-based noninvasive testing will facilitate progress toward the implementation of a noninvasive approach for screening for trisomy 21, 18, and 13. In this review, we highlight the principle of dPCR and discuss its future implications in clinical practice.

• Journal of Dairy Science and Biotechnology
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• 제38권4호
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• pp.169-188
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• 2020

Salmonella spp. is the most common cause of gastrointestinal food poisoning worldwide, and human salmonellosis is mostly caused by the consumption of contaminated food. Therefore, the development of rapid detection methods for Salmoenlla spp. and rapid identification of the source of infection by subtyping are important for the surveillance and monitoring of food-borne salmonellosis. Therefore, this review introduces (1) History and nomenclature of Salmoenlla spp., (2) Epidemiology of Salmoenlla spp., (3) Detection methods for Salmoenlla spp. - conventional culture method, genetic detection method, molecular detection methods, and aptamer, and (4) Subtyping methods for Salmoenlla spp. - pulsed-field gel electrophoresis and repetitive sequence-based polymerase chain reaction (PCR).

• Journal of Microbiology
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• 제40권1호
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• pp.70-76
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• 2002

Proviral DNAs from HIV-1-infected CD4+ T cells (Molt/LAV cells) were amplified and detected in infected individual cells using polymerase chain reaction and in rifu hybridization. In this in situ PCR, three parameters were considered to achieve effective amplification and retention of amplificants inside the cells by making high molecular weight PCR products intracellularly, forming agarose matrix against the cells, and maintaining the appropriate PCR temperature profile. Over the cycles of ampliHcationl tailed primers with complementary overhanging sequences at their 5' sides manufactured high molecular weight products by using short primary products as a repeating unit. Agarose matrix could prevent the diffusion of the amplificants from the cells. Use of Thermanox coverslip inside the PCR tube offered target cells a similar temperature profile to that of conventional PCR in solution.

• International Journal of Oral Biology
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• 제44권3호
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• pp.96-100
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• 2019

The purpose of this study was to develop Peptoniphilus mikwangii-specific quantitative real-time polymerase chain reaction (qPCR) primers based on the 16S ribosomal RNA (16S rDNA) gene. The specificity of the primers was determined by conventional PCR using 29 strains of 27 oral bacterial species including P. mikwangii. The sensitivity of the primers was determined by qPCR using the purified genomic DNA of P. mikwangii KCOM $1628^T$ (40 ng to 4 fg). The data showed that the qPCR primers (RTB134-F4/RTB134-R4) could detect P. mikwangii strains exclusively and as little as 40 fg of the genomic DNA of P. mikwangii KCOM $1628^T$. These results suggest that the developed qPCR primer pair can be useful for detecting P. mikwangii in epidemiological studies of oral bacterial infectious diseases.

• 대한의생명과학회지
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• 제6권1호
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• pp.55-63
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• 2000

PCR을 이용한 임상가검물 중에서 보편화된 객담 이외에 미량의 각종 체액과 임상에서 많이 실시하지 않는 파라핀 포매 조직에서의 결핵균 검출을 실험하여 그 활용 가능성을 규명하고자 하였다. 임상가검물인 체액 65예는 항산성 염색과 배양검사, PCR을 실시하였고, 파라핀 포매 조직 50예는 항산성 염색과 병리조직학적 진단, PCR을 실시하여 다음과 같은 결론을 얻었다. 본 실험 검체 중 임상가검물인 체액에서 항산성 염색 음성인 검체 중 12.1%,배양검사에서 음성인 검체 중 3.7%에서 PCR 양성의 결과를 보였고, 파라핀 포매 조직에서는 항산성 염색 음성인 검체 중 20.0%에서 PCR양성의 결과를 얻어 PCR이 민감도와 특이도가 높음을 확인할 수 있었다.

• 생명과학회지
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• 제21권7호
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• pp.947-952
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• 2011

현재까지 다수의 역학연구를 통해 피부에 발생한 보통사마귀에서 제 1, 2, 3, 4, 7, 10, 27, 57 및 65형의 인유두종바이러스가 검출되었다. 그러나 기존의 중합효소연쇄반응(conventional polymerase chain reaction, PCR)을 이용하는 경우 절차가 복잡하여 시간이 오래 걸리는 단점이 있었다. 이번 연구를 통해 저자들은 보통사마귀에서 가장 흔히 검출되는 6가지 유전자형의 인유두종바이러스를 한번에 확인 가능한 간편한 muliplex PCR의 개발을 목표로 하였다. 인유두종바이러스의 염기서열분석을 통해, L1에서 E6, 그리고 E2에서 L2 사이의 유전자간영역(intergenic region)으로 부터 6쌍의 primer를 고안하였으며, L1 유전자서열 분석을 통해 multiplex PCR의 특이성을 확인하였다. 총 129개의 조직표본 중 109개에서 제 1, 2, 3, 4, 27, 57형의 인유두종바이러스를 확인하였다. 이번 연구의 primer를 이용한 인유두종바이러스 검출의 민감도와 특이도는 각각 85%와 99.5%였다. 이러한 primer 세트로 인유두종바이러스가 검출되지 않은 20개의 조직표본의 경우, 또 다른 HPV primer를 사용한 추가적인 multiplex PCR을 시행하여 7개 표본에서 제 7형 및 65형의 인유두종바이러스가 검출되었다. 이상의 결과는 본 연구를 통해 새롭게 고안된 multiplex PCR 기법을 통해 보통사마귀에서의 인유두종바이러스를 보다 정확하고 빠르게 검출할 수 있다는 것을 보여 준다.

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.276-282
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• 2004

Marginal Zn deficiency is prevalent through the world and yet human zinc status has not been properly assessed due to the lack of a reliable diagnostic indicator. One potential possibility for zinc status assessment using Zn-binding protein, metallothionein (MT)-mRNA, has been proposed. The purpose of the present study was aimed to show whether measurement of mononuclear cell (MNC) MT mRNA, using a competitive-reverse transcriptase-polymerase chain reaction (competitive-RT-PCR) assay, could indicate zinc status in human subjects. In this study, MNC MT-mRNA expression was measured using a competitive-RT-PCR to compare before and after 14 days of zinc supplementation (50 mg Zn/das zinc gluconate). RT-PCR oligonucleotide primers which were designed to amplify both a 278 bp segment of the human MT-2A cDNA and a 198 bp mutant competitor cDNA template from MNCs, were prepared. MT-2A mRNA was normalized by reference to the housekeeping gene, $\beta$-actin, mRNA for which was also measured by competitive-RT-PCR. There was considerable inter-individual variation in MT-mRNA concentration and yet, the mean MT-2A mRNA level increased 4.7-fold after Zn supplementation, as compared to before Zn supplementation. This MT-2A mRNA level was shown as the same pattern and, even more sensitive assay, compared to the conventional plasma and red blood cells (RBCs) Zn assessment in which plasma and RBCs zinc levels increased 2.3- and 1.2-fold, respectively (p<0.05). We suggest that MT competitive-RT-PCR can be a useful assessment tool for evaluating human zinc status.

• Fisheries and Aquatic Sciences
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• 제24권11호
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• pp.351-359
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• 2021

The red sea bream iridovirus (RSIV) belonging to genus Megalocytivirus is responsible for red sea bream iridoviral disease (RSIVD) in marine and freshwater fishes. Although several diagnostic assays for RSIV have been developed, diagnostic sensitivity (DSe) and specificity (DSp) of real-time polymerase chain reaction (PCR) assays are not yet evaluated. In this study, we developed a TaqMan probe-based real-time PCR method and evaluated its DSe and DSp. To detect RSIV, the probe and primers were designed based on consensus sequences of the major capsid protein (MCP) genes from megalocytiviruses including RSIV, infectious spleen and kidney necrosis virus (ISKNV), and turbot reddish body iridovirus (TRBIV). The probe and primers were shown to be specific for RSIV, ISKNV, and TRBIV-types megalocytiviruses. A 95% limit of detection (LOD_95%) was determined to be 5.3 viral genome copies/µL of plasmid DNA containing the MCP gene from RSIV. The DSe and DSp of the developed real-time PCR assay for field samples (n = 112) were compared with those of conventional PCR assays and found to be 100% and 95.2%, respectively. The quantitative results for SYBR Green and TaqMan probe-based real-time PCR were not significantly different. The TaqMan probe-based real-time PCR assay for RSIV may be used as an appropriate diagnostic tool for qualitative and quantitative analysis.