• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.589-593
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• 1998

DNA amplification by polymerase chain reaction (PCR) was used to specifically detect Plasmodiophora brassicae, causing clubroot of crucifers. On the basis of DNA sequence informations, an oligonucleotide primer set specific for the pathogen was designed form small subunit gene (18S-like) and internal transcribed spacer (ITS) region of ribosomal DNA. Primer ITS 5/PB-C produced an amplification product of approximately 520 bp in length with DNA from P. brassicae. However, no amplification product was produced with DNAs from several soil-borne fungi, Didymella bryoniae and Rhizopus stolonifer. Using these primers, the clubroot pathogen was readily detected from infected roots of crucifers, but not from healthy roots. Southern hybridization analysis further confirmed that the amplification product was originated from P. brassicae.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.289-295
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• 2010

The bacterium Deinococcus radiodurans is one of the most resistant organisms to the effects of ionizing radiation and other DNA-damaging agents. In this study, distributions of 10 ddr (DNA damage response) genes were investigated in 8 species of Deinococcus by polymerase chain reaction (PCR). We have compared the sequences of ddr genes of D. radiodurans, D. geothermalis and D. deserti, and selected primers which are suitable for the detection of ddr in different species of Deinococcus. A sequence homology search and PCR assay showed that ddrO, which encodes a global regulator of the radiation-desiccation response, was most well conserved in the Deinococcus lineage.

• The Plant Pathology Journal
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• v.39 no.1
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• pp.141-148
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• 2023

Black shoot blight disease caused by Erwinia pyrifoliae has serious impacts on quality and yield in pear production in Korea; therefore, rapid and accurate methods for its detection are needed. However, traditional detection methods require a great deal of time and fail to achieve absolute quantification. In the present study, we developed a droplet digital polymerase chain reaction (ddPCR) method for the detection and absolute quantification of E. pyrifoliae using a pair of species-specific primers. The detection range was 10³-10⁷ copies/ml (DNA templates) and cfu/ml (cell culture templates). This new method exhibited good linearity and repeatability and was validated by absolute quantification of E. pyrifoliae DNA copies from samples of artificially inoculated immature pear fruits. Here, we present the first study of ddPCR assay for the detection and quantification of E. pyrifoliae. This method has potential applications in epidemiology and for the early prediction of black shoot blight outbreaks.

• The Korean Journal of Pain
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• v.18 no.2
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• pp.210-213
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• 2005

Acute viral meningitis and myositis are rare complications of varicella-zoster virus (VZV) reactivation. A 71-years-old immunocompetent man, who presented with lower back pain radiating to the left lower extremities, developed vesicles on the L5 dermatomal area. The next day, he had complained of aberrant vesicles on the trunk, face and scalp, with generalized myalgia, headache and dizziness. He was confirmed with VZV meningitis and myositis, as demonstrated by the presence of VZV DNA in the blood and cerebral spinal fluid using a polymerase chain reaction (PCR) amplification. PCR has been used in patients with a VZV infection associated neurological symptoms, and provides a useful tool for the early diagnosis of VZV-associated neurological disease. The patient was treated with bed rest, with intravenous acyclovir for the VZV infection, and intravenous Patient-controlled Analgesia for pain management and the prevention of postherpetic neuralgia. When he visited the outpatient department 3 months later, the skin lesion, leg pain, headache and myalgia had all improved, without sequelae. Here, this case is reported, with a discussion of the relevant literature on its diagnosis and management.

• Journal of Dairy Science and Biotechnology
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• v.38 no.4
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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).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.10 s.253
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• pp.1261-1268
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• 2006

This paper reports low-cost microreactor $(10{\mu}{\ell})$ biochip for the DNA PCR (polymerase chain reaction). The microbiochip $(20mm{\times}28mm)$ is a hybrid type which is composed of PDMS (polydimethylsiloxane) layer with serpentine micochannel $(360{\mu}m{\times}100{\mu}m)$ chamber and glass substrate integrated with microheater and thermal microsensor. Undesirable bubble is usually created during sample loading to PMDS-based microchip because of hydrophobic chip surface. Created bubbles interrupt stable biochemical reaction. We designed improved microreactor chamber using microfluidic simulation. The designed reactor has a coner-rounded serpentine channel architecture, which enables stable injection into hydrophobic surface using micropipette only. Reactor temperature needed to PCR reaction is controlled within ${\pm}0.5^{\circ}C$ by PID controller of LabVIEW software. It is experimentally confirmed that SRY gene PCR by the fabricated microreactor chip is performed for less than 54 min.

• Korean Journal of Veterinary Service
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• v.31 no.1
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• pp.87-91
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• 2008

Between March and October 2007, a total of 516 blood samples from pigs in the Gyeonggi province were examined for seroprevalence against toxoplasmosis by latex agglutination test (LAT) and the detection of antigenic particles among seropositive samples by PCR. In the LAT, 118 (22.8%) were positive, and the unadjusted percentage of seroprevalence rates of breeding and fattening pigs were significant difference. Positive rate (14.1%) in the breeding pigs was much lower than that (27.8%) of the fattening pigs (p<0.001, Pearson's Chi-square test). The antibody detection rate of sows was lower than fattening pigs, i.e., 15.8% (25/158) and 26% (93/358), respectively (P=0.011, Pearson's Chi-square test). Among 118 seropositive samples by LAT, 68 (57.6%) were positive in PCR for the detection of the toxoplasma specific-DNA. There was a statistical difference in the positive PCR reaction between the raising pigs(63/93 67.7%) and sows (5/25, 20%) (P<0.01).

• Korean Journal of Veterinary Service
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• v.37 no.1
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• pp.29-33
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• 2014

This study aimed at finding a fast, sensitive, and efficient protocol for molecular identification of intracellular protozoa Toxoplasma (T.) gondii. For molecular detection of T. gondii, we developed a polymerase chain reaction coupled with dot blot hybridization assay (PCR/DBH). For DBH analysis, the amplified DNA of T. gondii tachyzoite was labeled by incorporation of digoxigenin. The DBH assay alone was capable of detecting down to $1{\times}10^4$ pg of T. gondii genomic DNA. The PCR alone was capable of detecting down to $1{\times}10^3$ pg of T. gondii genomic DNA, whereas the PCR/DBH assay was capable of detecting down to $1{\times}10^2$ pg of T. gondii genomic DNA, indicating that sensitivity of the PCR/DBH method was approximately 10 to 100 times higher than PCR or DBH alone. Our PCR/DBH assay will be useful for confirming the presence of T. gondii on the samples and differentiating T. gondii infection from other intracellular protozoa infections.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.387-391
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• 2005

Competitive polymerase chain reaction (cPCR) was used to develop a direct enumeration method of Listeria monocytogenes in pork meat. Pork meat was artificially inoculated with L. monocytogenes and DNA was extracted using guanidine thiocyanate-phenol-chloroform and subjected to PCR amplification. Sixteen primer sets for L. monocytogenes hlyA gene were tested for sensitive detection and the DG69/DG74 primer set was selected. The detection limit achieved with this primer set was as low as 860 colony-forming units (cfu) per 0.1 g of pork meat. When the samples were cultured at $30^{\circ}C$ for 16 hr in Brain Heart Infusion (BHI) medium, even a single bacterium could be detected with this primer set by PCR. For cPCR, the hlyA gene, which features a 148 bp-deletion, was cloned in the pGEM-4Z vector. A known amount of competitor DNA which has the same primer binding sites was co-amplified with L. monocytogenes total DNA from the artificially inoculated pork meat. The cell-number determined by cPCR was approximately equal to cfu from the Most Probable Number (MPN) method. The whole procedure took only 5 hr.

• BMB Reports
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• v.30 no.1
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• pp.26-32
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• 1997

Of all HLA class I molecules, HLA-C gene products are most poorly understood because they express at a low level on the cell surface compared to HLA-A and -B. In order to identify serologically detectable and undetectable HLA-C antigens, we have established a DNA-based tissue typing method for the HLA-C locus by PCR-SSP (polymerase chain reaction-sequence specific primers). Genomic DNA prepared from Iymphoblastoid 21 B-cell lines and 120 Korean individuals by proteinase K digestion and pheno/chloroform extractions have been typed by PCR-SSP (23 primer mixes were used). The PCR-SSP results of control cell lines were discrepant from serology in 1 case among 21 cases: Cw6 which was negative by serology but positive by PCR-SSP (cell line: MANIKA). Twenty four HLA-Cw "blank" antigens among fifty Korean individuals were completely determined by PCR-SSP DNA typing. HLA-Cw*0101 (15.3%), Cw*1401 (12.3%) and Cw*0701 (11.7%) alleles were frequently found in 120 Korean individual samples. In conclusion. the high level of discrimination for HLA-C alleles may prove useful and informative in the study of transplant survival, and identify the importance of allelic differences, not readily detectable by serology, on host and donor compatibility.