• Korean Journal of Veterinary Service
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• v.34 no.4
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• pp.333-339
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• 2011

Loop-mediated isothermal amplification (LAMP) was developed to detect Mycobacterium tuberculosis complex (MTC) and non-tuberculous mycobacterium (NTM) genomic DNA in blood samples of Korea native cattle. A set of four primers, two outer and two inner, were designed from M. bovis and M. avium genomic DNA targeting the IS6110 and 16S rRNA gene, respectively. Based on 85 Intradermal Tuberculin Test (ITT) positive blood sample and using conventional PCR and LAMP, the agreement quotient (kappa), which measures agreement beyond chance were 0.93 (conventional PCR) and 0.97 (LAMP), respectively. The detection limit of the LAMP method was $2.0{\times}10^2$ copy/ml M. bovis and M. avium cells, compared to $2.0{\times}10^3$ copy/ml M. bovis and M. avium cells for conventional PCR. These results suggest that the LAMP is a powerful tool for rapid, sensitive, and practical detection of MTC and NTM in blood samples of Korea native cattle.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.486-489
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• 1996

A simple, rapid, specific and sensitive method for the detection of serum hepatitis C virus (HCV) RNA using the reverse transcription-polymerase chain reaction (RT-PCR) technique without conventional RNA extraction was developed. HCV template RNA from serum was obtained by boiling the serum at $95^{\circ}C$ for 2 min, cooling rapidly in ice and removing the proteins by cetrifugation. RT-PCR amplifications including the reverse transcription and first PCR amplification were performed in one vessel containing both of reverse transcriptase and Taq DNA polymerase. The detection of HCV RNA from $10^{-3}{\mu}l$. serum was possible with this method. The suitability of this method for clinical analysis was evaluated by assaying HCV RNA in 225 patient samples including anti-HCV antibody negatives (13 samples) and positives (212 samples) by enzyme-linked immunosorbent assay test (ELISA). Detections of HCV RNA with this method were in 4 of 13 anti-HCV antibody negative samples (30.8%) and 95 of 212 positive samples (44.8%). The present method can be completed in 1 hr and has a wide range of application for the clinical utilities to determine the viral RNAS.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.1
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• pp.27-32
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• 2017

This paper presents a Daubechies wavelet-based fault detection method for fault identification in transmission lines. After the Daubechies wavelet coefficients are calculated, the proposed algorithm has been implemented difference equation using C language. We have modeled a 154kV transmission line using the ATPDraw software and have acquired test data. In order to evaluate effects of DC offset, simulations carried out while varying an inception angle of the voltage $0^{\circ}$, $45^{\circ}$, $90^{\circ}$. For performance evaluation, fault distance was varied. As we can see from the off-line simulation, the proposed algorithm shows rapid and accurate fault detection. Also we can see the proposed algorithm is not affected by the fault inception angle change.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.8
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• pp.371-378
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• 2002

This paper presents the rapid and accurate algorithm for fault detection and location estimation in the transmission line. This algorithm uses wavelet transform for fault detection and harmonics elimination and utilizes least square error method for fault impedance estimation. Wavelet transform decomposes fault signals into high frequence component Dl and low frequence component A3. The former is used for fault phase detection and fault types classification and the latter is used for harmonics elimination. After fault detection, an adaptive data window technique using LSE estimates fault impedance. It can find a optimal data window length and estimate fault impedance rapidly, because it changes the length according to the fault disturbance. To prove the performance of the algorithm, the authors test relaying signals obtained from EMTP simulation. Test results show that the proposed algorithm estimates fault location within a half cycle after fault irrelevant to fault types and various fault conditions.

• BMB Reports
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• v.39 no.3
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• pp.247-252
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• 2006

A rapid method for the detection of Hepatitis E Virus (HEV) was developed by utilizing nano-gold labeled oligonucleotide probes, silver stain enhancement and the microarray technique. The 5'-end -$NH_2$ modified oligonucleotide probes were immobilized on the surface of the chip base as the capture probe. The detection probe was made of the 3'-end -SH modified oligonucleotide probe and nano-gold colloid. The optimal concentrations of these two probes were determined. To test the detection sensitivity and specificity of this technique, a conservative fragment of the virus RNA was amplified by the RT-PCR/PCR one step amplification. The cDNA was hybridized with the capture probes and the detection probes on microarray. The detection signal was amplified by silver stain enhancement and could be identified by naked eyes. 100 fM of amplicon could be detected out on the microarray. As the results, preparation of nano-gold was improved and faster. Development time also was shortened to 2 min. Thus, considering high efficiency, low cost, good specificity and high sensitivity, this technique is alternative for the detection of HEV.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.306-311
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• 2002

PCR of the mecA gene for the rapid detection of methicillin-resistant staphylococci was perfomed and compared with the antibiotic sensitivity test. A total of 43 strains of staphylococi from clinical specimens were used in this study. An antibiotic sensitivity test by the agar dilution method of NCCLS (The National Commitee for Clinical Laboratory Standard) was performed for the strains. Among them, 39 isolates were methicillin-resistant (MRS), and 4 isolates were methicillin-susceptible (MSS). With the exception for one strain (Staphylococcus cohnii, HRC2-4), all MRS strains amplified the expected 533 bp fragments of the mecA gene by PCR, However, one strain (Staphylococcus aureus, HSA1-10) that was classified as a sensitive strain by the antibiotic sensitivity test was mecA positive by PCR. All 35 methicillin-resistant Staphylococcus aureus (MRSA) strains were mecA positive, but overall, concordance between the results of the mecA PCR and antibiotic sensitivity test was 95.6%.

• Korean Journal of Veterinary Service
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• v.23 no.4
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• pp.349-360
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• 2000

An epidemiological survey was conducted to investigate fowl typhoid outbreaks in Kyungnam province of Korea. The causative agent, salmonella gallinarum was isolated from 68 chicken samples of tentatively diagnosed fowl typhoid cases occurred during the period from January 1996 to September 1999. Comparative studies were also carried out to evaluate the diagnostic methods for detection of S gallinam The results obtained were as follows; 1. Of the 68 cases of tentatively diagnosed fowl typhoid, 56 (82%) cases were determined as fowl typhoid by biochemical test and pathological findings. The other 12 (18%) cases were determined as paratyphoid. 2. Fowl typhoid outbreaks occur continuously all seasons in the year, however the incidence was remarkably increased from May to September. 3. The frequency of incidence of fowl typhoid in terms of regional distribution was relatively high in egg-laying hens facilities, and the mode of transmission is likely to be either egg-to-egg or lateral transfer by wild birds or rats. 4. All of 18 isolates from 56 cases were identified as S gallinarum by biochemical and serological test. 5. Antimicrobial drug susceptibility test against 18 isolates showed that the isolates were highly susceptible to ASH, CZ, CF and GM (above 90%), whereas those strains were 100% resistant to EM, NA and PC. 6. S gallinarum rfbS gene was targeted to be amplified by PCR for comparative detection of S gallinarum in the experimentally infected chickens. The amplified 720bp DNA fragment, which is specific in D serogroup strains of S enterica subspecies was confirmed by agarose gel electrophoresis. 7. A comparison made between fecal culture and PCR-method revealed that later-method was relatively higher in detection rate than that of former method for S gallinarum. 8. Comparison of currently applied methods, rapid serum agglutination test (RST) and microplate agglutination test (MAT), with experimentally infected chickens were made to evaluate sensitivity of detection by neutralizing antibody titration. Both methods detected neutralizing antibodies from the challenged chickens of 5 day post infection. However, positive reactions were determined after 7 and 9 days post infection by MAT and RST, respectively.

• Korean Journal of Clinical Laboratory Science
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• v.46 no.4
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• pp.136-139
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• 2014

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the severe nosocomial infectious agents. The traditional diagnostic methods including biochemical test, antibiotic susceptibility test and PCR amplification are time consuming and require much work. The Surface enhanced Raman spectroscopy (SERS) biosensor is a rapid and powerful tool for analyzing the chemical composition within a single living cell. To identify the biochemical and genetic characterization of clinical MRSA, all isolates from patients were performed with VITEK2 gram positive (GP) bacterial identification and Antibiotic Susceptibility Testing (AST). Virulence genes of MRSA also were identified by DNA based PCR using specific primers. All isolates, which were placed on a gold coated nanochip, were analyzed by a confocal Raman microscopy system. All isolates were identified as S. aureus by biochemical tests. MRSA, which exhibited antibiotic resistance, demonstrated to be positive gene expression of both femA and mecA. Furthermore, Raman shift of S. aureus and MRSA (n=20) was perfectly distinguished by a confocal Raman microscopy system. This novel technique explained that a SERS based confocal Raman microscopy system can selectively isolate MRSA from non-MRSA. The study recommends the SERS technique as a rapid and sensitive method to detect antibiotic resistant S. aureus in a single cell level.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.158-165
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• 2006

Although Mycobacterium tuberculosis complex strains remain responsible for the majority of diseases caused by mycobacterial infections worldwide, the increase in HIV infections has allowed for the emergence of other non-tuberculous mycobacteria as clinically significant pathogens. However, Mycobacterium species has a long period of incubation, and requires serious biochemical tests such as niacin, catalase, and nitrate test that are often tedious. The development of rapid and accurate diagnostics can aid in the early diagnosis of disease caused by Mycobacterium. The current DNA amplification and hybridization methods that have been developed target several genes for the detection of mycobacterial species such as hps65, 16S rDNA, rpoB, and dnaj. These methods produce rapid and accurate results. In this study, PCR-restriction fragment length polymorphism analysis(PCR-RFLP) based on the region of the rpoB gene was used to verify the identification of non-tuburculosis Mycobacterium species. A total of 8 mycobacterial reference strains and 13 clinical isolates were digested with restriction enzymes such as Msp I in this study. The results of using this process clearly demonstrated that all 13 specimens were identified by rpoB gene PRA method. The PCR-RFLP method based on the rpoB gene is a simple, rapid, and accurate test for the identification of Mycobacterium.

• Research in Plant Disease
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• v.20 no.1
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• pp.21-24
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• 2014

Clubroot caused by the obligate biotrophic protist Plasmodiophora brassicae Woronin is one of the most damaging diseases of Brassicaceae family. In this study, we developed species-specific primer sets for rapid and accurate detection of P. brassicae. The primer sets developed amplified a specific fragment only from P. brassicae DNA while they did not amplify a band from 10 other soilborne pathogens or from Kimchi cabbage. In sensitivity test, the species-specific primer set ITS1-1/ITS1-2 could work for approximately 10 spores/ml of genomic DNA showing more sensitivity and accuracy than previous methods. With quantitative real-time PCR test, the primer set detected less spores of P. brassicae than before, confirming that the species-specific primer set could be useful for rapid and accurate detection of P. brassicae.