• 제목/요약/키워드: Screening curve method

검색결과 53건 처리시간 0.026초

잔류 Sulfamethazine 검출용 ELISA 개발에 관한 실험적 연구 (Experimental Study on Development of ELISA Method for the Detection of Sulfamethazine Residues)

  • 임윤규;김성희
    • 한국식품위생안전성학회지
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    • 제10권4호
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    • pp.213-217
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    • 1995
  • A screening method has been developed for detecting sulfamethazine(SMZ) contamination of meat or feeds by using horseradish peroxidase (HRP) labeled protein A (Prot AHRP)and an indirect competitve enzyme-linked immunosorbent assay(ELISA). The assay is based on competitve binding of guinea pig anti-SMZ with SMZ in smaple and SMZ-gelatin conjugate(SMZ.GEL). Percent binding (B.Bo$\times$100) was calculated from the absorbance in the absence (B0) and presence (B) of SMZ. By the sandard curve prepared by plotting log(SMZ) vs percent binding of each known reference solution, the detection limit was 1.0ppb or less. Cross reacton with sulfadimethoxine, sulfaguaniding, sulfamerazine, sulfamthoxpyridazine, sulfanilamide, sulfisomidine and sufisoxazole were not observed. But sulfamerazine crossreacted in the test. The EC-50 value (concentration causing 50% inhibition of color development compared with blank) of sulfamerazine was 2.0 ppm. Further quality control will make the ELISA system ideal for the detection of SMZ in meat or feeds.

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Statistical Method of Ranking Candidate Genes for the Biomarker

  • Kim, Byung-Soo;Kim, In-Young;Lee, Sun-Ho;Rha, Sun-Young
    • Communications for Statistical Applications and Methods
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    • 제14권1호
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    • pp.169-182
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    • 2007
  • Receive operating characteristic (ROC) approach can be employed to rank candidate genes from a microarray experiment, in particular, for the biomarker development with the purpose of population screening of a cancer. In the cancer microarray experiment based on n patients the researcher often wants to compare the tumor tissue with the normal tissue within the same individual using a common reference RNA. Ideally, this experiment produces n pairs of microarray data. However, it is often the case that there are missing values either in the normal or tumor tissue data. Practically, we have $n_1$ pairs of complete observations, $n_2$ "normal only" and $n_3$ "tumor only" data for the microarray. We refer to this data set as a mixed data set. We develop a ROC approach on the mixed data set to rank candidate genes for the biomarker development for the colorectal cancer screening. It turns out that the correlation between two ranks in terms of ROC and t statistics based on the top 50 genes of ROC rank is less than 0.6. This result indicates that employing a right approach of ranking candidate genes for the biomarker development is important for the allocation of resources.

Mid-upper-arm circumference as a screening measure for identifying children with elevated body mass index: a study for Pakistan

  • Asif, Muhammad;Aslam, Muhammad;Altaf, Saima
    • Clinical and Experimental Pediatrics
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    • 제61권1호
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    • pp.6-11
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    • 2018
  • Purpose: Mid-upper-arm circumference (MUAC) is considered an alternative screening method for obesity. The aims of this investigation were to examine the ability of MUAC to correctly identify children with elevated body mass index (BMI) and to determine the best MUAC cutoff point for identification of children with high BMI. Methods: Anthropometric measurements (height, weight, and MUAC) from a cross-sectional sample of 7,921 Pakistani children aged 5-14 years were analyzed. Pearson correlation coefficients between MUAC and other anthropometric measurements were calculated. Receiver operating characteristic curve analysis was used to determine the optimal MUAC cutoff point for identifying children with high BMI. Results: Among 7,921 children, the mean (${\pm}$standard deviation) age, BMI, and MUAC were 10.00 (${\pm}2.86years$), 16.16 (${\pm}2.66kg/m^2$), and 17.73 (${\pm}2.59cm$), respectively. The MUAC had a strong positive correlation with BMI. The optimal MUAC cutoff points indicating elevated BMI in boys ranged from 16.76 to 22.73, while the corresponding values in girls ranged from 16.38 to 20.57. Conclusion: MUAC may be used as a simple indicator of overweight/obesity in children, with reasonable accuracy in clinical settings.

Clq-coated ELISA법을 이용한 정맥용 면역글로불린제제의 항보체성 측정 (Clq-Coated Microtitre Enzyme-linked Immunosorbent Assay for Measuring the Anticomplementary Activity of Intravenous Immunoglobulin Preparations)

  • 강혜나;김순남;신광훈;허숙진
    • 약학회지
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    • 제45권6호
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    • pp.656-663
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    • 2001
  • The quality of an intravenous immunoglobulin preparation (IVIG) is reflected by the degree of nonspecific activation of complements, the so-called anticomplementary activity (ACA). ACA of aggregates in IVIG was investigated using method by the European Pharmacopoeia and Clq-coated microtiter enzyme-linked immunosorbent assay (ELISA). Both the EP method and the ELISA method showed a dose response curve with the amount of complements bound increasing with the percentage content of aggregates in immunoglobulin standard. The correlation between the two tests was good (r=0.96, r=0.99). However, the correlation was not found when the ACA (EP method) of IVIG product was compared with its aggregate percentage. These results emphasize that the method of aggregate formation affects ACA and that estimation of the percentage distribution of aggregates by HPLC may not reflect ACA. In analysing WIG product for Clq binding activity test with the ELISA, the result by using Protein A-HRP correlated with aggregate percentage (r=0.84). But the correlation decreased (r=0.48) when the result used Protein A-AP(having poorer sensitivity than HRP) was compared with aggregate percentage. As a result, some variation between the two methods, due to differences in assay principles, is to be expected. However, ELISA technique has the advantage in that it is easier to perform, more precise and less subject to reagent variability, and is the more suitable screening method than HPLC analysis.

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A Multicenter Pilot Study of Biliary Atresia Screening Using Digital Stool Color Imaging

  • Kannamon Waitayagitgumjon;Wannisa Poocharoen;Suchin Trirongjitmoah;Kriengsak Treeprapin;Arada Suttiwongsing;Thetiya Wirifai;Chira Trirongchitmoh;Pitiporn Tangkabuanbutr
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제27권3호
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    • pp.168-175
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    • 2024
  • Purpose: The presence of alcoholic stool in biliary atresia (BA) patients is the basis of a stool color card (SCC), a screening tool that has led to more patients receiving Kasai portoenterostomy earlier. This study aimed to evaluate the color image processing of stool images captured using smartphones. We propose that measuring digital color parameters is a more objective method for identifying BA stools and may improve the sensitivity of BA screening. Methods: A prospective study was conducted in five hospitals in Thailand between October 1, 2020, and December 31, 2021. Stools from infants presenting with jaundice, acholic stool, or dark-colored urine were photographed. Digital image color analysis was performed, and software was developed based on the color on the original SCC. Sensitivity and specificity for predicting BA stools were compared between the SCC and the software. Results: Of 33 infants eligible for data collection, 19 were diagnosed with BA. Saturation and blue were two potential digital color parameters used to differentiate BA stools. The receiver operating characteristic curve was used to determine the optimum cutoff point of both values, and when saturation ≤56 or blue ≥61 was set as a threshold for detecting BA stool, high accuracy was achieved at 81.8% and 78.8%, respectively. Conclusion: Digital image processing is a promising technology. With appropriate cutoff values of saturation in hue, saturation, value and blue in red, green, blue color models, BA stools can be identified, and equivocal-colored stools of non-BA patients can be differentiated with acceptable accuracy in infants presenting with jaundice.

Development of a Label-Free LC-MS/MS-Based Glucosylceramide Synthase Assay and Its Application to Inhibitors Screening for Ceramide-Related Diseases

  • Fu, Zhicheng;Yun, So Yoon;Won, Jong Hoon;Back, Moon Jung;Jang, Ji Min;Ha, Hae Chan;Lee, Hae Kyung;Shin, In Chul;Kim, Ju Yeun;Kim, Hee Soo;Kim, Dae Kyong
    • Biomolecules & Therapeutics
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    • 제27권2호
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    • pp.193-200
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    • 2019
  • Ceramide metabolism is known to be an essential etiology for various diseases, such as atopic dermatitis and Gaucher disease. Glucosylceramide synthase (GCS) is a key enzyme for the synthesis of glucosylceramide (GlcCer), which is a main ceramide metabolism pathway in mammalian cells. In this article, we developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine GCS activity using synthetic non-natural sphingolipid C8-ceramide as a substrate. The reaction products, C8-GlcCer for GCS, could be separated on a C18 column by reverse-phase high-performance liquid chromatography (HPLC). Quantification was conducted using the multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z $588.6{\rightarrow}264.4$ for C8-GlcCer at positive ionization mode. The calibration curve was established over the range of 0.625-160 ng/mL, and the correlation coefficient was larger than 0.999. This method was successfully applied to detect GCS in the human hepatocellular carcinoma cell line (HepG2 cells) and mouse peripheral blood mononuclear cells. We also evaluated the inhibition degree of a known GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) on GCS enzymatic activity and proved that this method could be successfully applied to GCS inhibitor screening of preventive and therapeutic drugs for ceramide metabolism diseases, such as atopic dermatitis and Gaucher disease.

열병합발전이 전력수급 및 환경에 미치는 영향에 관한 연구 (A Study on Effect Considering the Electricity Supply & Demand and Environment Using CHP)

  • 김용하;나인규;김동근;우성민;김미예;임현성;손승기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.521-522
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    • 2006
  • This paper calculates co-generation generating capacity for the electric supply and demand. CHP is applied to SCM(Screening Curve Method) to calculate CHP generating capacity On the other hand, small co-generation is applied to potential area conversing small co-generation generating capacity considering economic analysis and useful life. these methods executed project scheduled to construction plan. Accordingly, EES(Expected Energy Served), Fuel type consumption and CO2 effects is analyzed by Booth-Baleriaux and data

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EIS 기반 전압신호 분석을 통한 당뇨병 진단 가능성 평가 (Diagnosis of Diabetes Using Voltage Analysis Based on EIS (Electro Interstitial Scan))

  • 배장한;김수찬;카니티카 케오칸네트;전민호;김재욱
    • 전자공학회논문지
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    • 제53권11호
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    • pp.114-122
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    • 2016
  • EIS (Electro interstitial scan, 전기체간스캔법)는 전극을 이용해 미세전류를 인체에 인가하고 그에 따른 전기적 반응을 분석하여 생리적인 정보를 얻는 방법으로, 비침습적이고 간단한 검사가 가능하다는 장점이 있다. 특히 당뇨병 진단을 위한 스크린용으로 적합하다는 연구들이 진행되어 왔으나 대부분 진단 원리에 대한 구체적인 논의가 이루어지지 않았다. 본 연구에서는 EIS 방법이 당뇨병 스크리닝 및 임상에 유용하게 활용될 수 있을지 분석해 보기위해 당뇨병 환자와 정상인을 대상으로 EIS 장비의 원 신호인 전압 변동 데이터를 특정경로에서 측정하였다. 전압 신호의 특징점을 추출하고 두 그룹 사이의 AUC (Area under the curve)를 계산한 결과 7개의 변수들이 60% 이상의 분류 정확도를 보였다. 또한 이 변수들을 k-NN 분류기로 학습한 결과, 왼쪽 손에서의 전압 변동 크기를 기준으로 분석했을 때 분류 정확도를 76.2%까지 높일 수 있었다. EIS 기반의 전압신호 분석법으로 비침습적인 당뇨병 스크리닝의 가능성을 보였다.

위암 검출에서 혈중 Pepsinogen검사의 의의 (The Role of Serum Pepsinogen in Detection of Gastric Cancer)

  • 류형균;박전우;이건호;전창호;이호준;채현동
    • Journal of Gastric Cancer
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    • 제9권4호
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    • pp.167-171
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    • 2009
  • 목적: 정상인과 위암 환자의 혈중 Pepsinogen (PG)농도를 비교 분석하여 선별검사로서 이용가능성 및 위암의 임상 조직학적 요소와의 상관 관계를 알아보고자 하였다. 대상 및 방법: 2008년 11월부터 2009년 5월까지 대구가톨릭대학병원에서 내시경상 특이소견이 없는 정상인과 위선암 환자의 수술 전 혈중 PG농도를 측정하였다. 위암진단의 선별검사로서의 이용가능성을 알아 보기 위해 receiver operator characteristics (ROC) curves를 이용하여 가장 유용한 검사법을 선별하였고, 위암 조직과의 상관관계를 알아보기 위해 특정 기준치에 따라 임상 조직학적 요소를 비교 분석하였다. 결과:선별검사로서 혈중 PG I/II 비율이 가장 유용하였고, 기준치에 따른 민감도, 특이도는 81.8%, 82%로 나타났다. 임상 조직학적 요소 중 Lauren분류에 따른 종양의 아형(P=0.003), TNM 병기의 T 병기(P=0.001), 및 종양주위의 만성 위축성 위염(P=0.036)을 동반한 위선암이 특정기준치(cut off point)값에 의미 있는 관련을 보였다. 결론: 본 연구는 정상 대조군의 수가 적어 선별검사로서 혈중 PG측정의 유용성을 논하기에는 부족하나, 위암의 선별검사로서 이용 가능성 및 임상 조직학적 요소와 의미 있는 관련을 보여 차후 추가연구가 필요할 것으로 생각한다.

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Clinical Evaluation of Human Papillomavirus Detection by careHPVTM Test on Physician-Samples and Self-Samples using The Indicating FTA Elute® Card

  • Wang, Shao-Ming;Hu, Shang-Ying;Chen, Feng;Chen, Wen;Zhao, Fang-Hui;Zhang, Yu-Qing;Ma, Xin-Ming;Qiao, You-Lin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권17호
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    • pp.7085-7090
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    • 2014
  • Objective: To make the clinical evaluation of a solid-state human papillomavirus (HPV) sampling medium in combination with an economical HPV testing method ($careHPV^{TM}$) for cervical cancer screening. Methods: 396 women aged 25-65 years were enrolled for cervical cancer screening, and four samples were collected. Two samples were collected by woman themselves, among which one was stored in DCM preservative solution (called "liquid sample") and the other was applied on the Whatman Indicating FTA $Elute^{(R)}$ card (FTA card). Another two samples were collected by physician and stored in DCM preservative solution and FTA card, respectively. All the samples were detected by $careHPV^{TM}$ test. All the women were administered a colposcopy examination, and biopsies were taken for pathological confirmation if necessary. Results: FTA card demonstrated a comparable sensitivity of detecting high grade Cervical Intraepithelial Neoplasia (CIN) with the liquid sample carrier for self and physician-sampling, but showed a higher specificity than that of liquid sample carrier for self-sampling (FTA vs Liquid: 79.0% vs 71.6%, p=0.02). Generally, the FTA card had a comparable accuracy with that of Liquid-based medium by different sampling operators, with an area under the curve of 0.807 for physician &FTA, 0.781 for physician &Liquid, 0.728 for self & FTA, and 0.733 for self &Liquid (p>0.05). Conclusions: FTA card is a promising sample carrier for cervical cancer screening. With appropriate education programmes and further optimization of the experimental workflow, FTA card based self-collection in combination with centralized $careHPV^{TM}$ testing can help expand the coverage of cervical cancer screening in low-resource areas.