• Asian Pacific Journal of Cancer Prevention
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• 제16권2호
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• pp.657-660
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• 2015

Background: A diagnosis of H. pylori infection can be made by invasive or non-invasive methods. Several noninvasive diagnostic tests based on the detection of H. pylori stool antigen (HpSA) have been developed. The Genx H. pylori stool antigen card test is a new rapid, non-invasive test that is based on monoclonal immunochromatographic assay. The aim of this study was to determine its sensitivity, specificity, and diagnostic accuracy for diagnosing H. pylori infection in adult patients. Materials and Methods: A total of 162 patients were included in the study. A gastric biopsy was collected for histopathology and rapid urease testing. Stool specimens for HpSA testing were also collected. Patients were considered H. pylori positive if two invasive tests (histological and rapid urease tests) were positive. Results: Using the reference test, 50.6% of the samples were positive for H. pylori infection. The Genx H. pylori antigen test was positive in 19.7% of patients. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the Genx H. pylori antigen test were 51.6%, 96.0%, 88.8%, 76.1%, and 79.0%, respectively. Conclusions: The Genx H. pylori stool antigen card test is a new non-invasive method that is fast and simple to perform but provides less reliable results.

• Journal of Preventive Medicine and Public Health
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• 제42권4호
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• pp.223-230
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• 2009

Objectives : This study was conducted to validate self-reported smoking among high school students using urinary cotinine. Methods : A self report of smoking behavior was collected together with urine sample for cotinine analysis from 130 male and female students in two vocational high school students in November, 2007. Validity and agreement between self-reported smoking and urinary cotinine was analyzed with STATA 9.0 for different definitions of current smokers, and frequent and daily smokers. Urinary cotinine concentration was measured by the DRI Cotinine Assay for urine (Microgenics Corp., Fremont, CA) on Toshiba 200FR. The cut-off point of urinary cotinine was 50 ng/dl. Results : The concentrations of urinary cotinine were significantly different according to the frequency and amount of smoking. Sensitivity and specificity was 90.9% and 91.8% respectively, and the Cohen s kappa value was 0.787 among the current smokers who smoked at least one day during one month preceding the survey. The comparable high sensitivity, specificity, and kappa value were shown also among the other definitions of current smokers, that is, subjective smokers, and weekly smokers. Conclusions : The results showed the high validity of self-reported smoking among high school students. However, due to the small sample size and limitation of the participants, it is cautious to generalize the results to overall high school students.

• Fisheries and Aquatic Sciences
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• 제9권1호
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• pp.38-43
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• 2006

We developed and evaluated a method of short-term acute toxicity testing based on the feeding behavior of Ceriodaphnia dubia. In prior toxicity tests, neonates of C. dubia were hatched and cultivated with the addition of yeast only for the preparation of the transparent daphnid's gut. Scenedesmus subspicatus was supplied as food after 1 to 6 h of exposure to toxicants. The effects of 1-h and 6-h exposure time on test sensitivity did not significantly differ. A comparison of the short-term l-h acute toxicity test developed in this study to the standard 48-h acute toxicity test using heavy metals, cyanide, and pentachlorophenol indicated that the 1-h test provided an acceptable sensitivity level in toxicity testing of C. dubia..

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2006년도 Principles and Practice of Microarray for Biomedical Researchers
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• pp.71-76
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• 2006

Comparative genomic hybridization (CGH) is a technique for studying chromosomal changes in cancer. As cancerous cells multiply, they can undergo dramatic chromosomal changes, including chromosome loss, duplication, and the translocation of DNA from one chromosome to another. Chromosome aberrations have previously been detected using optical imaging of whole chromosomes, a technique with limited sensitivity, resolution, quantification, and throughput. Efforts in recent years to use microarrays to overcome these limitations have been hampered by inadequate sensitivity, specificity and flexibility of the microarray systems. The oligonucleotide CGH microarray system overcomes several scientific hurdles that have impeded comparative genomic studies of cancer. This new system can reliably detect single copy deletions in chromosomes. The system includes a whole human genome microarray, reagents for sample preparation, an optimized microarray processing protocol, and software for data analysis and visualization. In this study, we determined the sensitivity, accuracy and reproducibility of the new system. Using this assay, we find that the performance of the complete system was maintained over a range of input genomic DNA from 5 ug down to 0.15 ug.

• 한국표면공학회지
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• 제55권6호
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• pp.342-352
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• 2022

Purine catabolite screening enables reliable diagnosis of certain diseases. In this regard, the development of a facile detection strategy with high sensitivity and selectivity is demanded for point-of-care applications. In this work, the simultaneous detection of uric acid (UA), xanthine (XA), and hypoxanthine (HX) was carried out as model purine catabolites by surface-enhanced Raman Spectroscopy (SERS). The detection assay was conducted by employing high-aspect ratio Au nanopillar substrates coupled with in-situ Au electrodeposition on the substrates. The additional modification of the Au nanopillar substrates via electrodeposition was found to be an effective method to encapsulate molecules in solution into nanogaps of growing Au films that increase metal-molecule contact and improve substrate's sensitivity and selectivity. In complex solutions, the approach facilitated ternary identification of UA, XA, and HX down to concentration limits of 4.33 𝜇M, 0.71 𝜇M, and 0.22 𝜇M, respectively, which are comparable to their existing levels in normal human physiology. These results demonstrate that the proposed platform is reliable for practical point-of-care analysis of biofluids where solution matrix effects greatly reduce selectivity and sensitivity for rapid on-site disease diagnosis.

• Archives of Pharmacal Research
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• 제13권3호
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• pp.215-220
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• 1990

Two different, derivative spectrophotometric and gas-liquid chromatographic, procedures for direct quantitation of caffeine and some commonly dispensed antihistaminics in bulk forms, in their laboratory prepared mmixtures and in dosage formulations, have been investigated. The limit, sensitivity reproducibility and accuracy of each method were studied for each individual drug substance and in some usual pharmaceutical formulations.

• The Plant Pathology Journal
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• 제33권6호
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• pp.589-596
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• 2017

Chemical management of dollar spot in turf may lead to the development of Sclerotinia homoeocarpa populations with reduced fungicide sensitivity. The objective of this study was to investigate resistance of S. homoeocarpa isolates to triazole fungicides and to test cross-resistance among three triazole fungicides. A total of 66 isolates of S. homoeocarpa were collected from 15 golf courses across Korea, and tested via in vitro sensitivity assay against hexaconazole, propiconazole and tebuconazole. $EC_{50}$ values of the isolates to these fungicides were distributed in the range of $0.001-1.1\;a.\;i.\;{\mu}g\;ml^{-1}$. Based on the $EC_{50}$ values, twelve representative strains were selected as sensitive isolates including control and insensitive isolates with respect to each fungicide. At a concentration of $0.1\;a.\;i.\;{\mu}g\;ml^{-1}$ for all fungicides, the selected strains were distinguished as sensitive or resistant isolates with the mycelial growth inhibition rate of 50% as the criterion. The $EC_{50}$ values of resistant strains exposed to hexaconazole, propiconazole and tebuconazole were 20-50 times, 50-70 times, and 77 times greater, respectively, than that of the control strains. Two isolates of S. homoeocarpa S0-41 and Sh14-2-1 showed sensitivity toward all the fungicides used, while two other isolates Sh7-5-1 and Sh2-1-1 showed resistance to all fungicides. Each isolate showed similar resistance to the three types of triazole fungicides, whereby cross-resistance of isolates was confirmed in the present study; all three triazole fungicide combinations displayed significant correlation coefficients equivalent to or greater than 0.8.

• Molecules and Cells
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• 제38권7호
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• pp.638-642
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• 2015

Quercetin can suppress osteosarcoma cell growth and metastasis. However, other effects of quercetin on osteosarcoma remain largely unknown. This research aims to evaluate the effects of quercetin in combination with cisplatin as treatment for osteosarcoma and investigate its regulatory mechanism. Cell viability and apoptosis in 143B cell line were determined after treatment with quercetin and/or cisplatin. RT-PCR and Western blot analysis were performed to determine the RNA or protein expression levels. Moreover, transwell assay was used to evaluate metastasis. Furthermore, rescue experiments were performed to investigate the potential regulatory mechanism of the treatment. Results showed that quercetin with concentration that was equal to or greater than $10{\mu}M$ inhibited 143B proliferation, while $5{\mu}M$ quercetin enhanced the cisplatin sensitivity of 143B cells. Expression of miR-217 was upregulated after quercetin and/or cisplatin treatment, while its target KRAS was downregulated both at mRNA and protein levels. MiR-217 knockdown led to the loss of enhanced cisplatin sensitivity while miR-217 overexpression showed the opposite effects, indicating that quercetin regulated cisplatin sensitivity by modulating the miR-217-KRAS axis. In conclusion, $5{\mu}M$ quercetin enhanced the cisplatin sensitivity by modulating the miR-217-KRAS axis. This finding suggests that quercetin may be administered with cisplatin to improve the treatment for osteosarcoma.

• Tuberculosis and Respiratory Diseases
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• 제66권1호
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• pp.13-19
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• 2009

연구배경: Interferon-gamma assay는 잠복 결핵의 진단에서 투베르쿨린 피부 반응 검사를 대신할 수 있는 검사 방법으로 주목 받고 있다. 그러나 활동성 결핵의 진단 시Interferon-gamma assay의 유용성에 대해서는 많은 이견이 있다. 따라서 결핵 발병률이 중등도인 우리 나라에서 Interferon-gamma assay의 임상적 유용성을 알아보고자 하였다. 방 법: 2007년 1월부터 2007년 8월까지 강동성심병원 호흡기내과에 내원한 환자 중 활동성 결핵이 의심되는 환자 52명을 대상으로 흉부 방사선 검사, 객담 도말 검사, 객담 배양 검사, PCR 검사, QuantiFERON-TB GOLD test를 시행하였다. 흉막 삼출액이 있는 환자의 경우 흉수 검사 및 흉막 조직 검사를 시행하였다. 결 과: 이번 연구에 포함된 52명의 환자 중 35명이 최종적으로 활동성 폐결핵으로 진단 되었고, 이 중 25명이 QuantiFERON-TB GOLD 검사 양성, 10명이 Quanti-FERON-TB GOLD 검사 음성 소견을 보였다. 본 연구에서 QuantiFERON-TB GOLD 검사의 민감도는 71.4%, 특이도는 64.7%였고, 양성 예측도는 0.83, 음성 예측도는 0.50였다. QuantiFERON-TB GOLD 검사 양성인 군과 음성인 군에서 C 반응성 단백값을 제외하고 두 군간에 큰 차이는 보이지 않았다. C 반응성 단백값은 QuantiFERON-TB GOLD 검사 양성인 군에서 29.25${\pm}$27.30 mg/L, Quanti-FERON-TB GOLD 검사 음성인 군에서 72.90${\pm}$67.98 mg/L로 QuantiFERON-TB GOLD 검사 음성인 군에서 통계적으로 유의하게 높게 나타났다(p<0.05). 결 론: 본 연구에서는 QuantiFERON-TB GOLD 검사는 활동성 폐결핵 진단에 유용성이 크지 않은 것으로 나타났다. QuantiFERON-TB GOLD 검사 결과와 C 반응성 단백값의 상관 관계는 추후 연구가 더 필요할 것으로 사료된다.

• Pediatric Infection and Vaccine
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• 제17권2호
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• pp.137-147
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• 2010

목적 : 본 연구는 소아에서 QuantiFERON-TB Gold(QTB) 검사의 임상적 유용성과 문제점을 평가하기 위해 시행되었다. 방 법: 2007년 1월부터 2009년 6월까지 본원에서 TST와 QTB를 시행 받은 소아청소년 112명의 의무 기록을 후향적으로 조사하였다. 결과 : TST와 QTB의 양성률은 각각 59.8%, 15.2%였고, 두 검사의 일치도는 낮았다($\kappa$=0.209). QTB의 민감도와 특이도는 각각 80.0%, 92.6%였다. QTB 양성율은 임상적 결핵군, 긴밀 접촉군, 일반 접촉군, 비접촉군에서 각각 80%, 14%, 0%, 2% 였으며, 판정보류의 빈도는 9.8%였다. QTB 추적 관찰이 시행된 환자 중, 초기 QTB 양성이었던 6명 중 5명은 치료 종료 후 평균 2.2개월까지 양성이 지속되었다. 결론 : 소아에서 QTB는 민감도가 낮고, 판정보류의 빈도가 높다는 단점이 있으나, 특이도가 높은 장점이 있으므로, TST의 특이도가 낮은 점을 보완하여 결핵의 진단 및 치료 결정에 활용될 수 있을 것으로 생각된다.