• Journal of Life Science
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• v.18 no.3
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• pp.374-380
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• 2008

Rapid detection of enterovirus (EVs) is important in the management of aseptic meningitis. We examined the relative efficiency and specificity of the real-time nucleic acid sequence-based amplification (NASBA) comparing with the established reverse transcription polymerase chain reaction (RT-PCR) and viral culture method which were used for the detection of enterovirus RNA in clinical specimens. Of the total 292 samples, 145 were found to be positive to enterovirus RNA by real-time NASBA, 101 were positive by viral culture, and 86 were positive by RT-PCR. 147 samples and 46 samples were determined to be negative and positive by all methods respectively, but 4 samples were positive only by real-time NASBA. To compare the specificity of each method, various clinical samples which were diagnosed for herpes simplex virus (HSV)-1, HSV-2, adenovirus, mumps, and rhinovirus were applied. Except one rhinovirus sample which was false positive to enterovirus RNA by RT-PCR, the other different samples were negative to all three methods. The real-time NASBA procedure can be completed within 5 hours in contrast with 9 hours for the RT-PCR and 3-14 days for the viral culture. From this study, it was suggested that the real-time NASBA assay could be a standardized, rapid, specific, and sensitive procedure for the detection of enterovirus RNA.

• Korean Journal of Clinical Laboratory Science
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• v.41 no.1
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• pp.42-46
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• 2009

Unlike most bacteria, Treponema pallidum subspecies cannot be readily isolated or sustained in cell culture for numerous generations. In korea, two non treponemal tests are currently considered as standard; the VDRL slide test and RPR card test. These tests are based on an antigen composed of an alcoholic solution containing measured amount of cardiolipin, cholesterol, and sufficient purified lecithin to produce reactivity. The nontreponemal reagin tests measure immunoglobulin M (IgM) and IgG to lipoidal material released from damaged host cells as well as to lipoprotein-like material and possibly by cardiolipin released from the treponemes. The object of the evaluation was to evaluate the performance of the Mediace RPR kit on the automated biochemistry analyzer system as a method for screen method of syphilis as well as to identify BFP possibility. For evaluation of routine screening test, a total 2,380 specimens tested by Mediace RPR from 28th Oct, 2007 to 22th Feb, 2008. For evaluation of BFP possiblility, we measured samples which have potential BFP reaction in Syphilis test such as ANA (anti-nuclear antibody) positive (135 samples), CRP (C-reactive protein) positive (100 samples), RF (Rheumatoid factor) positive (26 samples), and other potential BFP cases (17 samples) including total 278 samples. These samples were tested quantitative test Mediace RPR with Hitachi 7600 P module. For comparison with current manual test, VDRL slide test were performed. Of these 2380 specimens, 2350 were negative, 30 were positive, and one were positive with TPHA. Both methods agreed for 2356 (98.9%) samples. Of the 30 samples showed positive results over 1.0 R.U, 6 samples showed positive results with VDRL test. Of these 6 samples, 1 samples showed positive with TPHA test. The combination of the Automated Biochemistry analyzer and VDRL test for retest can be increase efficiency of syphilis screening test.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1032-1037
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• 1994

A simple, reproducible , and accurate enzymatic method using a cholesterol assay kit was developed to quantify total cholesterol content in egg yolk. Total egg yolk lipid was extracted with hexane : isopropanol(3 : 2, v/v) mixture. Samples containing various amount of the total lipid(0-3mg) in optically identifical culture tubes were reacted for 10 min in a water bath (37$^{\circ}C$) with the enzyme solution (5ml) from the cholesterol assay kit. Cholesterol content of the reaction mixturesin culture tubes was spectrophotometrically determined by two different ways : (1) using the culture tube as a curvette(designate culture tube method ; CTM) and (2) the quartz cvette containing the reaction mixture transferred from the culture tube (designate standard cvette method, SCM). CTM revealed lower cholesterol content in 0.1-1.0mg lipid sample range that SCM did, but not significant. For more than 2.0mg lipid sample, CTM gave significantly (p<0.01) lower cholesterol content relative to that by SCM, suggesting that SCM give a false positive result from the sample containing more than 2 mg lipid due to the interference of absorbance by lipid dispersed in the reaction solution . Cholesterol content of less than 1.0mg lipid sample by CTM was proportional to the amount of lipid used, but its linear relationship was not seen in more than 2mg lipid sample. Thus, to determine the appropriate lipid amounts (mg) analyzed . A constant level (41$\mu\textrm{g}$/mg) of cholesterol concentration was observed from the sample containing 0.1-1mg lipid. after which the cholesterol level was dropped to less than 41$\mu\textrm{g}$ /mg. Cholesterol concentration in egg yolk samples quantified by CTM was in accordance with that by GC method. These results suggest that CTM is an useful method for the quantification of cholesterol in egg yolk lipid and other lipids as well.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.281-289
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• 2000

Background : Mycobacterial culture is a confirmatory test to detect. M. tuberculosis, but it takes at least 6 weeks to diagnose. PCR is a rapid and sensitive method, but it is known that PCR has a high false positive rate due to contamination, and a high false negative rate due to inhibitors. It is also known that LCR and PCR-Hybridization, recently developed methods, are more specific methods than PCR in terms of detecting M. tuberculosis. In this study, we estimated the clinical utility of in house PCR, LCR and PCR-Hybridization for the detection of M. tuberculosis. Methods : We evaluated 75 specimens, upon which M. tuberculosis culture based testing was requested, by PCR LCR, and PCR-Hybridization and compared results. Mycobacterial culture was performed on 3% Ogawa media for 8 weeks, and an in house PCR, LCx Mycobacterium tuberculosis assay kit (Abbott Laboratories, North Chicago, III) and the AMPLICOR M. tuberculosis test kit (Roche Molecular Systems, Inc. Branchburg, NJ. USA). Results : In the view of the culture results, the sensitivities of the three tests were 40%, 80%, and 100% and their specificities were 98.6%, 94.3%, and 94.3%. Conclusion : LCR and PCR-Hybridization are rapid and sensitive methods for detecting M. tuberculosis in clinical laboratories.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.5
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• pp.432-443
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• 2005

Microarray technology has contributed Significantly to the understanding of bacterial genetics and transcriptional regulation. One neglected aspect of this technology has been optimization of microarray-generated signals and quality of generated information. Full genome microarrays were developed for Clostridium acetobutylicum through spotting of PCR products that were designed with minimal homology with all other genes within the genome. Using statistical analyses it is demonstrated that Signal quality is significantly improved by increasing the hybridization volume. possibly increasing the effective number of transcripts available to bind to a given spot, while changes in labeled probe amounts were found to be less sensitive to improving signal quality. In addition to Q-RT-PCR, array validation was tested by examining the transcriptional program of a mutant (M5) strain lacking the pSOL1 178-gene megaplasmid relative to the wildtype (WT) strain. Under optimal conditions, it is demonstrated that the fraction of false positive genes is 1% when considering differentially expressed genes and 7% when considering all genes with signal above background. To enhance genomic-scale understanding of organismal physiology, using data from these microarrays we estimated that $40{\sim}55%$ of the C. acetobutylicum genome is expressed at any time during batch culture, similar to estimates made for Bacillus subtilis.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.7 no.2
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• pp.153-162
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• 2004

Purpose: The Helicobacter pylori stool antigen (HpSA) enzyme immunoassay is a non-invasive test for the diagnosis and monitoring of H. pylori infection. But, there are few validation studies on the HpSA test after eradication in children. The aim of this study was to assess the diagnostic accuracy of HpSA enzyme immunoassay for the detection of H. pylori to confirm eradication in children. Methods: From January 2001 to October 2003, 164 tests were performed in 146 children aged 1 to 17.5 years (mean $9.3{\pm}4.3$ years). H. pylori infection was confirmed by endoscopy-based tests (rapid urease test, histology, and culture). All H. pylori infected children were treated with quadruple regimens (Omeprazole, amoxicillin, metronidazole and bismuth subcitrate for 7 days). Stool specimens were collected from all patients for the HpSA enzyme immunoassay (Primier platinum HpSA). The results of HpSA tests were interpreted as positive for $OD{\geq}0.160$, unresolved for $$0.140{\leq_-}OD$$<0.160, and negative for OD<0.140 at 450 nm on spectrophotometer. Results: 1) One hundred thirty-one HpSA tests were performed before treatment. The result of HpSA enzyme immunoassay showed three false positive cases and one false negative case. The sensitivity, specificity, positive predictive value, and negative predictive value of HpSA enzyme immunoassay before treatment were 96.4%, 97.1%, 90%, and 99%, respectively. 2) Thirty-three HpSA enzyme immunoassay were performed at least 4 weeks after eradication therapy. The results of HpSA enzyme immunoassay showed two false positive cases and one false negative case. The sensitivity, specificity, positive predictive value, and negative predictive value after treatment were 88.9%, 91.7%, 80%, and 95.7%, respectively. Conclusion: Diagnostic accuracy of the HpSA enzyme immunoassay after eradication therapy was as high as that of the HpSA test before eradication therapy. The HpSA enzyme immunoassay was found to be a useful non-invasive method to confirm H. pylori eradication in children.

• Korean Journal of Culture and Social Issue
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• v.14 no.4
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• pp.103-117
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• 2008

The polygraph test administered by the Korean Prosecutors Office for crime investigations customarily uses the score of -12 as the cutoff point separating the subjects who lie from those who tell the truth. The criterion used by the KPO is different from the one (-13) suggested by Backster (1963) who invented the particular method for lie detection. Based on the signal detection theory applied to the real polygraph test data obtained from real crime suspects by the KPO, the present study identified the score of -8 as an optimal criterion resulting in the highest overall accuracy of the polygraph test. The classification of the subjects with the score of -8 as the criterion resulted in the highest accuracy (83.17%) compared with the accuracies of classifications with the Backster's criterion (76.24%) and the KPO's criterion (80.20%). However, the new criterion was also found to result in more false-positive cases. Based on the results from the present study, it was recommended to use the score of -8 as the criterion when the overall accuracy is important but the score of -12 or -13 when avoiding false-positive is more important than securing the overall accuracy.

• Journal of the Korean Society of Food Culture
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• v.23 no.6
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• pp.737-747
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• 2008

This study was conducted to investigate the perception and understanding parents had regarding environment friendly agricultural products being used for school foodservice. A trained practitioner surveyed 221 parents of children at elementary schools in Daejeon using a questionnaire, after which the resulting data were analyzed by a Chi-square test. Overall, the parent's responses regarding the foodservice were positive. However, most of the parents do not participate (65%) in the school foodservice if they work, and those that do participate primarily work as meal service aides (58.1%). Parents indicated that the work of urgent field of inspection on food materials (69.9%), and the reason of an agreement (98.2%) for them were the students' health (68.4%). In addition, most parents were positive about the possibility of replacing foods used in the school with environment friendly products (51.6%) and felt that the government should pay the additional expense associated with their replacement. Furthermore, the majority of the parent's surveyed felt that children should be supplied with vegetables (54.9%) purchased directly from farms. The parents' satisfaction with the meal service (25.1%) was lower than that of the students (54.1%). The reason for the satisfaction reported by the parents was concern regarding the health of their children (53.3%). In addition, the majority of the parents (47.3%) responded that environment friendly agricultural products differ from general agricultural products because insecticides and fertilizer were not used. The main objection parents had to using environment friendly products was their cost (59.1%), and most parents felt that a realistic solution to this problem was unified purchase (41.4%). Besides, a problem when replacing with them was the expensive price (38.1%) and true or false (37.7%), and the students' satisfaction (59.5%) was selected the most in an effect of using them, diversity of the product (39.1%) and price reduction (32.6%) for a solution of the increase of using them.

• Clinical and Experimental Pediatrics
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• v.61 no.4
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• pp.114-120
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• 2018

Purpose: Routine screening for toxoplasmosis, rubella, cytomegalovirus (CMV), and herpes simplex virus (TORCH) in intrauterine growth restriction (IUGR) and small for gestational age (SGA) neonates has become a common practice. However, the incidence of TORCH varies across countries, and the cost of TORCH testing may be disadvantageous compared to disease-specific screening. To evaluate the efficacy of TORCH screening, the medical charts of IUGR or SGA neonates born in a single institution in Bucheon, Korea from 2011 to 2015 were reviewed. Methods: The clinical data of the 126 IUGR or SGA neonates were gathered, including gestational age, Apgar scores, neonatal sonographic findings, chromosome study, morbidities, developmental follow-up, and growth catch-up. Maternal factors including underlying maternal disease and fetal sonography were collected, and placental findings were recorded when available. TORCH screening was done using serum IgM, CMV urine culture, quantification of CMV DNA with real-time polymerase chain reaction, and rapid plasma reagin qualitative test for syphilis. Tests were repeated only for those with positive results. Results: Of the 119 TORCH screenings, only one was positive for toxoplasmosis IgM. This result was deemed false positive due to negative IgM on repeated testing and the absence of clinical symptoms. Conclusion: Considering the incidence and risk of TORCH in Korea, the financial burden of TORCH screening, and the single positive TORCH finding in our study, we suggest disease-specific screening based on maternal history and the clinical symptoms of the neonate. Regarding CMV, which may present asymptomatically, universal screening may be appropriate upon cost-benefit analysis.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.73-81
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• 1997

Diphtheria was the world-spread, respiratory infectious disease in the past. But after developing the diphtheria toxoid, diphtheria vaccine, composed of diphtheria toxoid, is generalized, so prevalence of diphtheria is sharply dropped. But diphtheria is come back in NIS(New Independent States) in 1990s. It is believed that recurrence of diphtheria is mainly due to shortage of protective diphtheria antibody titer in adults. And it is related to 70% prevalence in adults, not in children. Considering this changing environment, this study was designed to research the diphtheria antibody titer of whole population and existence of titer difference by sex. Also it was studied whether ELISA has fitness as determination method of diphtheria antibody titer compared with neutralization method on microcell culture. This study was done to 277 samples of three hospitals in Seoul area, and sera was tested by neutralization method on microcell culture and ELISA method. The results of this study were as follows 1) Of this studied population, 31.05% had an antibody titer below the protective level (<0.01 IU/ml), 40.79% had a titer of a relative degree of protection (0.01-0.09 IU/ml) and 28.16% had a reliable degree of protection ($\geq$0.1 IU/ml). Therefore, 68.95% had a basic protective antibody titer level. 2) 20-40 age group showed the lowest diphtheria antibody titer among the studied population. 3) GMT of diphtheria antibody titer was the highest in the children. But, after child period, GMT was fallen. Standard deviation value was the lowest in older group. 4) Protective level of diphtheria antibody titer of male was slightly higher than female (70.94% vs 66.66%). But this difference was not statistically significant. 5) Diphtheria antibody titer by ELISA method was wholly higher than by neutralization method on microcell culture. Compared the two results by ELISA and neutralization, the regression coefficient was 0.38. And in titer, which was obtained by ELISA method, false-positive results was abundant.