• 제목/요약/키워드: Quantitative Screening Method

검색결과 92건 처리시간 0.033초

A Cell-Based Assay System for Monitoring NF-$\kappa$B Activity in Human Epidermal Keratinocytes: A Screening Tool of the Antioxidants and Anti-inflammatories for Dermatological Purpose

  • Moon, Ki-Young;Hahn, Bum-Soo;Lee, Jinseon;Kim, Yeong-Shik
    • 대한화장품학회지
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    • 제27권1호
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    • pp.17-27
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    • 2001
  • A cell-based assay system for monitoring NF-$textsc{k}$B activity was developed to determine the influence of activated NF-$textsc{k}$B in human HaCaT cells. The pNF-$textsc{k}$B-SEAP-NPT plasmid that permits expression of the secreted alkaline phosphatase (SEAP) reported gene in response to the NF-$textsc{k}$B activity and contains neomycin phosphotransferase (NPT) gene for the geneticin resistance in host cells was constructed and transfected into human keratinocyte cell line HaCaT. Human HaCaT transfectant cells secreted the SEAP enzyme into the culture medium in a time-dependent manner until 72h. NF-$textsc{k}$B activities were measured in the SEAP reporter gene assay using a fluorescent detection method. The treatment of HaCaT cell transfectants with known antioxidants [e.g., N-acetyl-L-cysteine and vitamin C] showed inhibition of NF-$textsc{k}$B activity in a time-and concentration-dependent manner. The phorbol 12-myristate 13-acetate (PMA) known as a stimulator of NF-$textsc{k}$B expression demonstrated that it increased NF-$textsc{k}$B activity in a time- and concentration-dependent manner. This assay system could be used to determine the quantitative measurement of NF-$textsc{k}$B activity in the human skin and allow the screening of anti-inflammatory agents from various synthetic chemicals and natural products for dermatological purpose. Abbrevitions used: NF-$textsc{k}$B, nuclear factor kappa B; I-$textsc{k}$B, Inhibitory kappa B; SEAP, secreted alkaline phosphatase; NPT, neomycin phosphotransferease; PCR, polymerase chain reaction: dNTP, deoxynucleoside triphosphates; DMEM, dulbecco’s modified eagle medium; FBS, fetal bovine serum; PBs, phosphate-buffered saline; MUP, 4-methylumbellifery phosphate; NAC, N-acetyl-L-cysteine; DMSO, dimethyl sulfoxide; PMA, phorbol 12-myristate 13-acetate.

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Construction of a Large Synthetic Human Fab Antibody Library on Yeast Cell Surface by Optimized Yeast Mating

  • Baek, Du-San;Kim, Yong-Sung
    • Journal of Microbiology and Biotechnology
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    • 제24권3호
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    • pp.408-420
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    • 2014
  • Yeast surface-displayed antibody libraries provide an efficient and quantitative screening resource for given antigens, but suffer from typically modest library sizes owing to low yeast transformation efficiency. Yeast mating is an attractive method for overcoming the limit of yeast transformation to construct a large, combinatorial antibody library, but the optimal conditions have not been reported. Here, we report a large synthetic human Fab (antigen binding fragment) yeast surface-displayed library generated by stepwise optimization of yeast mating conditions. We first constructed HC (heavy chain) and LC (light chain) libraries, where all of the six CDRs (complementarity-determining regions) of the variable domains were diversified mimicking the human germline antibody repertoires by degenerate codons, onto single frameworks of VH3-23 and $V{\kappa}1$-16 germline sequences, in two haploid cells of opposite mating types. Yeast mating conditions were optimized in the order of cell density, media pH, and cell growth phase, yielding a mating efficiency of ~58% between the two haploid cells carrying HC and LC libraries. We constructed two combinatorial Fab libraries with CDR-H3 of 9 or 11 residues in length with colony diversities of more than $10^9$ by one round of yeast mating between the two haploid HC and LC libraries, with modest diversity sizes of ${\sim}10^7$. The synthetic human Fab yeast-displayed libraries exhibited relative amino acid compositions in each position of the six CDRs that were very similar to those of the designed repertoires, suggesting that they are a promising source for human Fab antibody screening.

현미에서의 오크라톡신 A의 검색을 위한 형광편광면역분석법의 응용 (Application of Fluorescence Polarization Immunoassay for the Screening of Ochratoxin A in Unpolished Rice)

  • 박정현;정덕화;이인선
    • 생명과학회지
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    • 제16권6호
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    • pp.1006-1013
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    • 2006
  • 식품안전에 대한 관심이 증가되고 있는 현재, 생물학적 화학적 위해요소로 분류되고 있고, 현재 많은 나라에서 규제치를 설정하고 있는 곰팡이 독소인 ochratoxin A(OTA)에 대한 정량적 측정이 가능한 고속검색법을 개발 하고자 단클론성 항체를 이용하여, 측정시 분리과정이 필요 없는 형광편광면역분석법(FPIA)을 개발하고 최적화 시켰다. 동일구조를 가지는 형광물질 표식자인 OTA-EDF를 합성하여 OTA에 대한 특이항체와 경쟁반응을 시켜 나타나는 형광-편광도(mP)의 변화를 측정하였다. 이는 면역분석법의 특이성과 민감성을 충분히 만족하였다. OTA의 검출범위는 0.5-200 ng/ml였고, 검출한계는 0.3 ng/ml였다. 개발된 분석법은 다른 곰팡이 독소들과의 교차반응은 없었고 높은 특이성과 재현성 및 회수율을 나타내었다. HPLC 방법에 의한 회수율은 88-84%로 다소낮게, FPlA법의 회수율은 90-110%로 다소 높게 나타났다. 16점의 현미시료를 분석하였을 때, 2점이 상관관계가 높게 12-20 ppb 정도 오염된 것으로 나타났다. 4점은 FPIA 및 HPLC 모두에서 음성으로 판정되었다. 개발된 FPIA는 복잡한 전처리 방법이 필요 없는 신속한 검색이 가능하므로, 식품 및 환경에서의 OTA 잔류 검사에 유용하게 사용될 수 있을 것이다.

화학공정 위험영향 평가기술에서의 다중요소분석기법을 이용한 사고시나리오 산정에 관한 전략 (A Strategy for the Generation of Accident Scenarios Using Multi-Component Analysis in Quantitative Risk Assessment)

  • 김구회;이동언;김용하;안성준;윤인섭
    • 한국화재소방학회논문지
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    • 제15권4호
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    • pp.24-33
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    • 2001
  • 현재 전세계적으로 공장내(on-site)뿐만 아니라 공장외지역(off-site)에 대한 사고영향평가의 필요성이 대두되고 있으며, 공장외지역에 대한 영향평가 수행후 이에 대한 적절한 비상계획을 제출하도록 하고 있고, 국내에서도 종합적위험관리체계(IRMS : Integrated Risk Management System)를 PSM이나 SMS와 더불어 시행 준비중에 있다. 그러나 공장외지역에 대한 위험영향 평가시 가장 먼저 결정되어야 할 가상시나리오에 대한 기준이 체계적으로 마련되어 있지 않아 사용자나 분석자에 따라 평가결과가 다양하게 나오며, 또한 공정에서 발생할 수 있는 사고의 이상원을 정확하게 파악하지 못한다는 단점이 있다. 따라서 본 연구에서는 이러한 가상시나리오를 결정하는데 필요한 공정요소를 분석한 후, 분석결과에 따라 발생 가능하고, 먼저 고려되어야 할 시나리오를 산정할 수 있도록 전략을 제시하고자 한다. 분석된 공정요소들은 요소에 따른 가중치를 부여하여 위험등급을 결정한 후 등급에 따른 위험영향 평가를 수행하도록 한다. 분석의 결과는 가상시나리오의 신뢰성을 향상시킴으로써 위험영향평가가 과대평가되는 것을 방지하고, 공정의 설계나 비상계획의 수립시 효과적이고 적절한 대책마련을 유도할 수 있다.

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New surveillance concepts in food safety in meat producing animals: the advantage of high throughput 'omics' technologies - A review

  • Pfaffl, Michael W.;Riedmaier-Sprenzel, Irmgard
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권7호
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    • pp.1062-1071
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    • 2018
  • The misuse of anabolic hormones or illegal drugs is a ubiquitous problem in animal husbandry and in food safety. The ban on growth promotants in food producing animals in the European Union is well controlled. However, application regimens that are difficult to detect persist, including newly designed anabolic drugs and complex hormone cocktails. Therefore identification of molecular endogenous biomarkers which are based on the physiological response after the illicit treatment has become a focus of detection methods. The analysis of the 'transcriptome' has been shown to have promise to discover the misuse of anabolic drugs, by indirect detection of their pharmacological action in organs or selected tissues. Various studies have measured gene expression changes after illegal drug or hormone application. So-called transcriptomic biomarkers were quantified at the mRNA and/or microRNA level by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) technology or by more modern 'omics' and high throughput technologies including RNA-sequencing (RNA-Seq). With the addition of advanced bioinformatical approaches such as hierarchical clustering analysis or dynamic principal components analysis, a valid 'biomarker signature' can be established to discriminate between treated and untreated individuals. It has been shown in numerous animal and cell culture studies, that identification of treated animals is possible via our transcriptional biomarker approach. The high throughput sequencing approach is also capable of discovering new biomarker candidates and, in combination with quantitative RT-qPCR, validation and confirmation of biomarkers has been possible. These results from animal production and food safety studies demonstrate that analysis of the transcriptome has high potential as a new screening method using transcriptional 'biomarker signatures' based on the physiological response triggered by illegal substances.

Multi-class, Multi-residue Analysis of 59 Veterinary Drugs in Livestock Products for Screening and Quantification Using Liquid Chromatography-tandem Mass Spectrometry

  • Yu Ra Kim;Sun Young Park;Tae Ho Lee;Ji Young Kim;Jang-Duck Choi;Guiim Moon
    • 한국환경농학회지
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    • 제41권4호
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    • pp.288-309
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    • 2022
  • BACKGROUND: The objective of this study was to develop a comprehensive and simple method for the simultaneous determination of 59 veterinary drug residues in livestock products for safety management. METHODS AND RESULTS: For sample preparation, we used a modified liquid extraction method, according to which the sample was extracted with 80% acetonitrile followed by incubation at -20℃ for 30 min. After centrifugation, an aliquot of the extract was evaporated to dryness at 40℃ and analyzed using liquid chromatography combined with tandem mass spectrometry. The method was validated at three concentration levels for beef, pork, chicken, egg, and milk in accordance with the Codex Alimentarius Commission/Guidelines 71-2009. Quantitative analysis was performed using a matrix-matched calibration. As a results, at least 52 (77.6%) out of 66 compounds showed the proper method validation results in terms of both recovery of the target compound and coefficient of variation required by Codex guidelines in livestock products. The limit of quantitation of the method ranged from 0.2 to 1119.6 ng g-1 for all matrices. CONCLUSION(S): This method was accurate, effective, and comprehensive for 59 veterinary drugs determination in livestock products, and can be used to investigate veterinary drugs from different chemical families for safety management in livestock products.

Prolactin Monomeric Polyethylene Glycol Measurement Method and Study of Reference Value Verification

  • Dong Hyuk Ha;Hwa-Jin Ryu;Hyun-Su Cho;Sun-Young Shin
    • 핵의학기술
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    • 제27권2호
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    • pp.133-136
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    • 2023
  • Purpose: Prolactin in the blood is separated into three types, and over 90% of prolactin presents as a double monomer (23 KDa). Rarely, it can exist in the size of big prolactin (150 KDa), which is called macroprolactin and is known as an autoantibody complex. When macroprolactin accounts for more than 60% of prolactin in the blood, it is called macroprolactinemia. The presence of such macroprolactin was first reported in a patient with hyperprolactinemia but without typical symptoms. Macroprolactinemia is emerging as an important cause of idiopathic hyperprolactinemia. The polyethylene glycol (PEG) precipitation method using the property of precipitating large-molecular-weight proteins is simple and recently has been widely used as a screening test. The results are in good agreement with the results of gel chromatography. The purpose of this study was to confirm the measurement method and reference value verification of monomeric prolactin in blood prolactin using the PEG precipitation method. Materials and Methods: For 40 examinees who visited the Gangnam Center of Seoul National University Hospital in 2021, the prolactin level was verified using radioimmunoassay (RIA). For macroprolactinemia PEG precipitation method, 25% PEG (molecular weight 6000kDa) solution and serum were mixed in equal amounts in a test tube, then left at room temperature for 20 minutes and centrifuged at 4℃ for 30 minutes (1500g). The prolactin level was measured in the supernatant. Results : After confirming that more than 90% of the 40 tested samples within the reference range <25 ng/mL, the same value as the reference value for prolactin was applied. Since the concentration of monomeric prolactin in serum from which macroprolactin has been removed from blood is diluted 1:1 with PEG, our laboratory is currently reporting the result by multiplying the result by a dilution factor of 2. Conclusion: Radioimmunoassay using PEG precipitation method using the property of precipitating large molecular weight proteins is simple and effective for quantitative measurement of monomeric prolactin in blood prolactin.

An Improved Calculation Model for Analysis of [111] InGaAs/GaAs Strained Piezoelectric Superlattices

  • Kim, Byoung-Whi;Yoo, Jae-Hoon;Kim, Soo-Hyung
    • ETRI Journal
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    • 제21권4호
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    • pp.65-82
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    • 1999
  • We present a calculation model for an improved quantitative theoretical analysis of electronic and optical properties of strained-piezoelectric[111] InGaAs/GaAs superlattices (SLs). The model includes a full band-coupling between the four important energy bands: conduction, heavy, light, and spin split-off valence bands. The interactions between these and higher lying bands are treated by the k ${\cdot}$ p perturbation method. The model takes into account the differences in the band and strain parameters of constituent materials of the heterostructures by transforming it into an SL potential in the larger band-gap material region. It self-consistently solves an $8{\times}8$ effective-mass $Schr{\ddot{o}}dinger$ equation and the Hartree and exchange-correlation potential equations through the variational procedure proposed recently by the present first author and applied to calculate optical matrix elements and spontaneous emission rates. The model can be used to further elucidate the recent theoretical results and experimental observations of interesting properties of this type of quantum well and SL structures, including screening of piezoelectric field and its resultant optical nonlinearities for use in optoelectronic devices.

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한의학 고문헌 텍스트에서의 인용문 추정과 탐색 (Detecting Local Text Reuse in the Texts of East Asian Traditional Medicine)

  • 오준호
    • 대한한의학원전학회지
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    • 제34권1호
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    • pp.37-45
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    • 2021
  • Objectives : The purpose of this paper was to examine quantitative methods for estimating and detecting local text reuse in the texts of East Asian Traditional Medicine. Methods : We introduce techniques that estimate the volume of local text reuse with n-gram and those that directly detect the reuse with the Smith-Waterman algorithm (SW algorithm). Based on this, the estimation and detection of local text reuse were carried out for 『Donguibogam』 and 『Huangdineijing·Suwen』. Results : Estimates with n-gram had more errors than methods with SW algorithms. SW algorithms detected suspected strings directly with local text reuse, resulting in more accurate results. Conclusions : Although n-gram does not accurately find local text reuse, its high speed makes it a preferable method for certain purposes, such as screening similar documents. On the other hand, SW algorithms have the advantage of being relatively good at finding similar phrases suspected as local text reuse even if the strings do not completely match. However, due to its excessive consumption of time and computing resources, its benefits are limited to cases where precise results are required.

Surgical outcomes of endoscopic versus open resection for the management of sinonasal malignancies

  • Rajendran, Balamurugan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제46권6호
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    • pp.373-378
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    • 2020
  • The purpose of this review is to assess the surgical outcomes of two different treatment modalities, endoscopic and open resection, for the management of sinonasal malignancies by comparing the effectiveness of these two methods. A wide search was carried out considering various electronic databases for English language articles from 2013 to 2018 using keywords such as sinonasal malignancies, endoscopic surgery, open resection for sinonasal malignancies, and endoscopic versus open surgery. One thousand articles were identified from the literature for screening. After a thorough systematic assessment and based on the selection criteria, 10 articles with 4,642 patients were included in this quantitative analysis. With a total of 4,642 patients, 1,730 patients were operated on using endoscopic resection and 2,912 patients were operated on using open resection. The endoscopic approach was found to have a shorter hospital stay compared to open surgical resection (P<0.05). The rate of positive margins and the recurrence rate for open surgical resection were both smaller compared to those for endoscopic resection (P>0.05), and the endoscopic approach had smaller complication rates and a higher survival rate compared to open resection (P>0.05). Though endoscopic resection and open surgical resection have comparable postoperative benefits, preoperative evaluation of cases presenting with sinonasal malignancies is necessary for determining the right treatment method to obtain the best possible results postoperatively.