• Journal of Periodontal and Implant Science
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• v.48 no.4
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• pp.261-271
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• 2018

Purpose: Few studies have examined periodontal pathogens from saliva samples in periodontally healthy young adults. The purposes of this study were to determine the prevalence of periodontopathic bacteria and to quantify periodontal pathogens in saliva samples using real-time polymerase chain reaction (PCR) assays in periodontally healthy Korean young adults under 35 years of age. Methods: Nine major periodontal pathogens were analyzed by real-time PCR in saliva from 94 periodontally healthy young adults. Quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, Peptostreptococcus anaerobius, and Eikenella corrodens was performed by DNA copy number measurement. Results: F. nucleatum and E. corrodens were detected in all subjects; the numbers of positive samples were 87 (92.6%), 91 (96.8%), and 90 (95.7%) for P. gingivalis, P. anaerobius, and C. rectus, respectively. Other pathogens were also detected in periodontally healthy subjects. Analysis of DNA copy numbers revealed that the most abundant periodontal pathogen was F. nucleatum, which was significantly more prevalent than all other bacteria (P<0.001), followed by P. anaerobius, P. gingivalis, E. corrodens, C. rectus, and T. denticola. There was no significant difference in the prevalence of each bacterium between men and women. The DNA copy number of total bacteria was significantly higher in men than in women. Conclusions: Major periodontal pathogens were prevalent in the saliva of periodontally healthy Korean young adults. Therefore, we suggest that the development of periodontal disease should not be overlooked in periodontally healthy young people, as it can arise due to periodontal pathogen imbalance and host susceptibility.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.193-201
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• 2013

Many consumers are increasingly concerned about the meat they eat, and accurate labelling is important due to public health, economic and legal concerns. Meat species adulteration is a common problem in the retail markets. In this study, a TaqMan$^{(R)}$ quantitative real-time polymerase chain reaction (PCR) assay was applied for its ability to quantify chicken meat, which was not indicated on the label, in 79 commercial pork products (ham, sausages, bacon and ground meat) producted by 10 different manufacturers. The amplification efficiency was 82.05% and the square regression coefficient ($R^2$) was 0.995. PCR results showed that 38.6% of ham samples, 50.0% of sausages samples, and 50.0% of ground meat samples were contaminated with chicken residuals, while the bacon samples were not contaminated with chicken residuals. Only twelve pork products of one of the manufacturers were in accordance with indicated in their labels. The PCR assay reported in this work could be particularly useful in inspection programs to verify the food labelling of commercial processed meats and to gain consumers' trust.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.5
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• pp.1239-1244
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• 2013

In the field of clinical medicine and research, the analysis of such as protein and DNA at the molecular level and even at the cell level are necessary for disease diagnosis and treatment. In many cases, a real time image of samples is needed for the accurate analysis and manipulation of samples since experimental samples are degenerated with time. In this research, a three-dimensional fluorescence microscope device was developed for taking images of protein and DNA inside a single cell and the server-client based image analysis system was made for an integrated management of the real-time images taken from the microscope device. The system consists of a fluorescent measurement device, the associated software and a client program on smartphone. The developed system allows doctors or experimental managers to receive and look at the real-time experimental images taken from the samples of patients anywhere in the emergency, to analyze results and to instantly diagnose the disease and to transfer the results to the patients. As a result, the system is able to be utilized in the implementation of ubiquitous health as well.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.203-209
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• 2005

Real time-polymerase chain reaction (RT-PCR) is currently considered as the most sensitive method to detect low abundant DNAs in samples. Compared to conventional PCR, real-time PCR has a high reliability because of excluding false-positive results and can allow a simultaneous faster detection and quantification of target DNAs. This study was carried out to identify the Hanwoo (Korean native cattle) beef by genotyping after DNA extraction of commercial beef in 41 restaurants. Since Hanwoo, Holstein and imported cattle meat have different patterns in the MC1R gene associated with the coat colors of cattles (C-type, C/T-type or T-type), we could identify the genotype using real-time PCR The result of real-time PCR assay for beef samples in 41 restaurants which are asserted to sell Hanwoo beef only, showed that 29 of 41 samples were Hanwoo beef gene type (T-type) and 12 of 41 samples were Holstein or imported cattle gene type (C-type or C/T-type). Therefore, the proportion of Han-woo beef was $70.7\%$ and the proportion of Holstein or imported cattle meat was $29.3\%(C/T-type; 12.2\%,\;C-type; 17.1\%)$.

• Korean Journal of Veterinary Service
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• v.34 no.4
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• pp.321-331
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• 2011

Mycobacterium bovis, a member of the M. tuberculosis complex (MTC), is the causative agent of bovine tuberculosis. Detection of M. bovis and M. tuberculosis using conventional culture- and biochemical-based assays is time-consuming. Therefore, a simple and sensitive molecular assay for rapid detection would be of great help in specific situations such as faster diagnosis of bovine tuberculosis (bTB) infection in the abattoirs. We developed a novel multiplex real-time PCR assay which was applied directly to biological samples with evidence of bTB and it was allowed to differentiate between M. bovis and M. tuberculosis. The primers and TaqMan probes were designed to target the IS1081 gene, the multi-copy insertion element in the MTC and the 12.7-kb fragment which presents in M. tuberculosis, not in the M. bovis genome. The assay was optimized and validated by testing 10 species of mycobacteria including M. bovis and M. tuberculosis, and 10 other bacterial species such as Escherichia coli, and cattle lymph nodes (n=113). The tests identified 96.4% (27/28) as M. bovis from the MTC-positive bTB samples using conventional PCR for specific insertion elements IS1081. And MTC-negative bTB samples (n=85) were tested using conventional PCR and the real-time PCR. When comparative analyses were conducted on all bovine samples, using conventional PCR as the gold standard, the relative accuracy of real-time PCR was 99.1%, the relative specificity was 100%, and the agreement quotient (kappa) was 0.976. The detection limits of the real-time PCR assays for M. bovis and M. tuberculosis genomic DNA were 10 fg and 0.1 pg per PCR reaction, respectively. Consequently, this multiplex real-time PCR assay is a useful diagnotic tool for the identification of MTC and differentiation of M. bovis and M. tuberculosis, as well as the epidemiologic surveillance of animals slaughtered in abattoir.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.655-662
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• 2004

The aim of this work was the validation of a rapid real-time PCR assay based on TaqMan technology for the unequivocal identification of infectious canine hepatitis (ICH) virus, to be used directly on DNA purified from blood specimens. A real-time PCR system targeting at the E3 ORFA gene sequence of canine adenovirus type 1 was optimized and validated through comparative analysis of samples using conventional PCR system. The real-time PCR assay based on TaqMan technology could disclose 23 (37.7%) out of 61 samples as PCR positive. In contrast, 18 (29.5%) samples were found PCR positive when conventional PCR was applied on these samples. The use of the ABI Prism 7700 sequence detection system allowed the efficient determination of the amplified product accumulation through a fluorogenic probe. The entire real-time TaqMan PCR assay, including DNA extraction, amplification, and detection could be completed within 3 hours. The detection method of real-time TaqMan PCR assay was 1,000 times more sensitive than conventional PCR. Real-time TaqMan probe and primer set developed and optimized in this study is a sensitive, rapid and accurate method for detection of ICH virus and can be effective screening tool for the detection of ICH in a diagnostic laboratory routines.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1516-1520
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• 2009

A sensitive technique for the determination of trace Co(II) in various samples after column preconcentration by adsorbing onto silica gel loaded with 1-nitroso-2-naphthol was developed. Several experimental conditions, such as pH of sample solution, the amount of silica gel loaded with 1-nitroso-2-naphthol, the flow rate for adsorption and so forth, were optimized. The interfering effects of diverse concomitant ions were investigated. Fe(III) interfered with more than any other ions, but the interference by Fe(III) was completely eliminated by adjusting the amount of silica gel loaded with 1-nitroso-2-naphthol to 0.30 g. The dynamic range, the correlation coefficient ($R^2$), and the detection limit obtained by the proposed technique were 3.0-140.0 ng m$L^{-1}$, 0.9942, and 1.81 ng m$L^{-1}$, respectively. For validating the technique, the aqueous samples (tap water, reservoir water, stream water, and wastewater) and the plastic samples were used as real samples. Recovery yields of 93.0-107.0% were obtained. These measured data were not different from ICP-MS data at the 95% confidence level by F test. Based on the results of the experiment, it has been found that the proposed technique can be applied to the determination of Co(II) in various real samples.

• Journal of Veterinary Clinics
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• v.32 no.6
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• pp.504-507
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• 2015

Coxiella burnetii is an obligate intracellular rickettsial organism and the causative agent of Query fever, a zoonosis that occurs worldwide. In Korea, C. burnetii infection had occurred in humans and animals. However, the studies were only conducted in geographically limited area for detection of C. burnetii. The objective of this study was to detect C. burnetii in Korean native cattle and dairy cattle nationwide by real-time PCR. The total of 807 blood samples from 622 Korean native cattle and 185 dairy cows, 170 individual milk samples of dairy cows, and 348 bulk tank milk samples of dairy herds were collected nationwide. From blood samples, C. burnetii was detected in 17 (2.7%) out of 622 Korean native cattle and 2 (1.1%) of 185 dairy cows. From milk samples, C. burnetii was detected in 27 (15.9%) out of 170 individual milk samples of dairy cows. And C. burnetii was detected in 84 (24.1%) of 348 bulk tank milk samples. In conclusion, this study revealed that the detection rates are considerably high in cattle and the infection of C. burnetii has been continuously occurring in cattle of Korea. In order to prevent the hazards of a zoonosis Q-fever that occur both humans and domestic animals, further studies are needed to clarify the epidemiology of Q-fever of domestic animals and humans in Korea.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1375-1382
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• 2007

A column preconcentration method with pulverized Amberlite XAD-4 loaded with bismuthiol I (BI) has been developed for the determination of trace Cd(II) and Cu(II) in various real samples by flame atomic absorption spectrophotometry. Various experimental conditions, such as the size of XAD-4, adsorption flow rate, amount of bismuthiol I, stirring time for adsorbing bismuthiol I on XAD-4, pH of sample solution, amount of XAD-4- BI, desorption solvent, and desorption flow rate, were optimized. Also, the adsorption capacity and the adsorption rate of Cd(II) and Cu(II) on XAD-4-BI were investigated. The interfering effects of various concomitant ions were investigated, Bi(III), Sn(II) and Fe(III) were found to affect the determination. But the interference by these ions was completely eliminated by adjusting the amount of XAD-4-BI resin to 0.70 g, although the adsorption flow rate was slower. For Cd(II) our proposed technique obtained a dynamic range of 0.5-40 ng mL-1, a correlation coefficient (R2) of 0.9913, and a detection limit of 0.3 ng mL-1. For Cu(II), the corresponding values were 2.0-120 ng mL-1, 0.9921 and 1.02 ng mL-1. To validate this proposed technique, the aqueous samples (stream water, reservoir water, tap water and wastewater), the diluted brass sample and the plastic sample, as real samples, were used. Recovery yields of 91-103% were obtained. These measured data were not different from ICP-MS data at 95% confidence level. Our proposed method was also validated using rice flour CRM (normal, fortified) samples. From the results of our experiment, we found that the technique we present here can be applied to the determination of Cd(II) and Cu(II) in various real samples.

• Analytical Science and Technology
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• v.25 no.3
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• pp.159-163
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• 2012

A spectrofluorimetric method has been developed for the determination of free $CN^-$ in real samples with fluorescent safranine-O. When safranine-O interacts electrostatistically with $CN^-$, the fluorescent intensity of safranine-O is decreased. Several experimental conditions such as pH of the sample solution and the amount of safranine-O were optimized. $Ag^+$ interfered higher than any other ions. Interference of $Ag^+$ could be disregarded because $Ag^+$ was scarcely contained or mostly complexed with $CN^-$ in selected real samples. With this proposed method, the linear range of $CN^-$ was from 5.0 to 110 ng/mL and the detection limit of $CN^-$ was 2.9 ng/mL. For validating this technique, real samples (Cu, Ag, Au electroplating wastewater, and untreated wastewater in university and in sewage treatment plant) were used. Recovery yields of 91.5%~106.0% were obtained. Based on experimental results, it is proposed that this technique can be applied to the practical determination of free $CN^-$.