• Title/Summary/Keyword: Real-time Reaction

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Rapid and Sensitive Detection of Hepatitis C Virus in Clinical Blood Samples Using Reverse Transcriptase Polymerase Spiral Reaction

  • Sun, Wenying;Du, Ying;Li, Xingku;Du, Bo
    • Journal of Microbiology and Biotechnology
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    • v.30 no.3
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    • pp.459-468
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    • 2020
  • This study established a new polymerase spiral reaction (PSR) that combines with reverse transcription reactions for HCV detection targeting 5'UTR gene. To avoid cross-contamination of aerosols, an isothermal amplification tube (IAT), as a separate containment control, was used to judge the result. After optimizing the RT-PSR reaction system, its effectiveness and specificity were tested against 15 different virus strains which included 8 that were HCV positive and 7 as non-HCV controls. The results showed that the RT-PSR assay effectively detected all 8 HCV strains, and no false positives were found among the 7 non-HCV strains. The detection limit of our RT-PSR assay is comparable to the real-time RT-PCR, but is more sensitive than the RT-LAMP. The established RT-PSR assay was further evaluated for detection of HCV in clinical blood samples, and the resulting 80.25% detection rate demonstrated better or similar effectiveness compared to the RT-LAMP (79.63%) and real-time RT-PCR (80.25%). Overall, the results showed that the RT-PSR assay offers high specificity and sensitivity for HCV detection with great potential for screening HCV in clinical blood samples.

Development of Laser Induced Real Time Photoacoustic Tomography Imaging System and Phantom Evaluation (레이저 유도방식의 실시간 광음향 단층영상 기술 개발과 팬텀이미지 평가)

  • Ryu, Sang-Hun;Shin, Dong-Ho;Song, Chul-Gyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.6
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    • pp.879-884
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    • 2012
  • Photoacoustic Tomography (PAT) is a promising medical imaging modality by reason of its particularity. It combines optical imaging contrast of optical imaging with the spatial resolution of ultrasound imaging and can demonstrate change of biological feature in an image. For that reason, many studies are in progress to apply this technic for diagnosis. But, real-time PAT system is necessary to confirm a biological reaction induced by external stimulation immediately. Thus, we developed a real-time PAT system using linear array transducer and self-developed Data acquisition board (DAQ) resources, To evaluate the feasibility and performance of our proposed system, two type of phantom test were also performed. As a result of those experiments, the proposed system shows enough performance and confirm its usefulness.

Comparison of Seven Commercial TaqMan Master Mixes and Two Real-Time PCR Platforms Regarding the Rapid Detection of Porcine DNA

  • Kang, Soo Ji;Jang, Chan Song;Son, Ji Min;Hong, Kwang Won
    • Food Science of Animal Resources
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    • v.41 no.1
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    • pp.85-94
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    • 2021
  • A pig-specific real-time PCR assay based on the mitochondrial ND5 gene was developed to detect porcine material in food and other products. To optimize the performance of assay, seven commercial TaqMan master mixes and two real-time PCR platforms (Applied Biosystems StepOnePlus and Bio-rad CFX Connect) were used to evaluate the limit of detection (LOD) as well as the PCR efficiency and specificity. The LODs and PCR efficiencies for the seven master mixes on two platforms were 0.5-5 pg/reaction and 84.96%-108.80%, respectively. Additionally, non-specific amplifications of DNA from other animal samples (human, dog, cow, and chicken) were observed for four master mixes. These results imply that the sensitivity and specificity of a real-time PCR assay may vary depending on master mix and platform used. The best combination of master mix and real-time PCR platform can accurately detect 0.5 pg porcine DNA, with a PCR efficiency of 100.49%.

A Study on the Validation system of Detection for Biological Agents Using Real-Time PCR (실시간 중합효소 연쇄반응을 활용한 생물작용제 검증시스템 연구)

  • Cha, Younggil;Koo, Bonwoo;Kim, Seongjoo;Kim, Namil;Park, Hanoh
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.5
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    • pp.726-732
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    • 2017
  • Bacillus anthracis, Vibrio cholerae, Variola virus and Shigella dysenteriae are classified as category A and B biological weapons. In this study suggest that 4 genes of Bacillus anthracis, 2 genes of Vibrio cholerae, 1 gene of Variola virus and 1 gene of Shigella dysenteriae were detective 50~500 fg of target DNA per reaction using real-time PCR based assay. Also analytical specificity did not show any cross-reactivity with other related bacteria. Reliable and one reaction could be effective early diagnostic and treatment for detection of unknown samples.

Preliminary study on the diversity and quantity analysis of oral bacteria according to the sampling methods (구강 세균 채취법에 따른 세균의 다양성과 양 분석을 위한 예비 연구)

  • Seon-Ju Sim;Ji-Hye Kim;Hye-Sun Shin
    • Journal of Korean society of Dental Hygiene
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    • v.24 no.2
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    • pp.131-139
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    • 2024
  • Objectives: Oral bacterial samples included subgingival, supragingival, and saliva plaques. As the diversity and number of microorganisms deffer depending on the area of the oral cavity and the method used, an appropriate and reliable collection method is important. The present study investigated oral bacterial sampling methods. Methods: Supragingival dental plaque was collected from the buccal and lingual tooth surfaces of study participants using sterilized cotton swabs. Plaques were collected from the subgingival area using a sterilized curette. Bacterial genomic DNA was extracted using MagNA Pure 96 DNA and Viral NA low-volume kits. Real-time polymerase chain reaction (PCR) was performed using the PowerCheckTM Periodontitis Pathogens Multiplex Real-time PCR kit. Results: Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Fusobacterium nucleatum of the orange complex were not observed in the subgingival biofilms of all study participants. For Porphyromonas. gingivalis, a significant correlation was observed between supragingival, subgingival, and total tooth surface biofilms. Compared to the supragingival and subgingival biofilmss, total tooth surface biofilm exhibited the highest bacterial count when the inswabbing method was used. Conclusions: Based on these findings, the supragingival swab method is recommended for oral bacterial research.

Study on the Enumeration of Legionella in Environmental Water Samples Using Real-time PCR (Real-time PCR을 이용한 환경 중 물 시료의 레지오넬라 분석법 연구)

  • Lee, Jung-Hee;Park, Myoung-Ki;Kim, Yun-Sung;Yun, Hee-Jeong;Lee, Chang-Hee;Jeong, Ah-Yong;Yoon, Mi-Hye
    • Journal of Environmental Health Sciences
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    • v.45 no.5
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    • pp.511-519
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    • 2019
  • Objectives: The standard method for the enumeration of environmental Legionella is culturing, which has several disadvantages, including long incubation and poor sensitivity. The purpose of this study is to demonstrate the usefulness of real-time PCR and to improve the standard method. Methods: In 200 environmental water samples, a real-time PCR and culture were conducted to detect and quantify Legionella. Using with the results of the survey, we compared the real-time PCR with the culture. Results: Each real-time PCR assay had 100% specificity and excellent sensitivity (5 GU/reaction). In the culture, 36 samples were positive and 164 samples were negative. Based on the results of the culture, real-time PCR showed a high negative predictive value of 99%, 35 samples were true positive, 105 samples were true negative, 59 samples were false positive and one sample was a false negative. Quantitative analysis of the two methods indicated a weak linear correlation ($r^2=0.29$, $r^2=0.61$, respectively). Conclusions: Although it is difficult to directly apply quantitative analysis results of real-time PCR in the enumeration of environmental Legionella, it can be used as a complementary means of culturing to rapidly screen negative samples and to improve the accuracy of diagnosis.

Reaction process in electrochromism of tungsten oxide thin films

  • An, Il-Sin;Lee, Chang-Hyo;Lim, Won-Taeg
    • Journal of Korean Vacuum Science & Technology
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    • v.2 no.2
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    • pp.85-91
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    • 1998
  • The electrochromic behaviors of de-magnetron sputtered tungsten oxide thin films were investigated during coloration and bleach cycles using in situ real-time spectroscopic ellipsometry. Effective medium approximation and least-squares regression analyses were employed to investigate the electrochromic process. The optical properties of the tungsten oxide film were analyzed using the oscillator model and the evolution of the process using a reaction-limited model. In these analyses, we found that two different reaction rates were associated with the process. We ascribe this behavior to the microstructure of this films.

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Simple and Rapid Detection of Potato leafroll virus by Reverse Transcription Loop-mediated Isothermal Amplification

  • Ju, Ho-Jong
    • The Plant Pathology Journal
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    • v.27 no.4
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    • pp.385-389
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    • 2011
  • A new reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the Potato leafroll virus (PLRV) was developed and compared with conventional reverse transcription polymerase chain reaction (RT-PCR) to address its advantages over RTPCR. RT-LAMP primers were designed from the open reading frame 3 (ORF3) sequence of PLRV. The RT-LAMP reactions were conducted without or with a set of loop primers. By real-time monitoring using Turbimeter, the RT-LAMP (with loop primers) detects PLRV in less than 30 min, compared to 120 min of RT-PCR. By adding fluorescent reagent during the reaction, final products of the RT-LAMP were fluorescently visualized under UV light or could be differentiated by naked-eye inspection under normal light. The RT-LAMP was extremely sensitive, about 2000-fold more sensitive than RT-PCR. This study presents great potential of the RT-LAMP for diagnosis and PLRV epidemiology because RT-LAMP method is speedy, sensitive, inexpensive, and convenient.

Study on Correlation between flashover and smoke production rate in real scale reaction-to-fire test (실대규모 화재시험시 플래시오버와 연기발생율간의 상관성 연구)

  • Park, Kye-Won;Im, Hong-Soon;Jeong, Jae-Gun;Kim, Woon-Hyung
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2010.04a
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    • pp.289-296
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    • 2010
  • This study is aiming at analyzing correlation between flashover's time and maximum smoke production rate's time on sandwich panel specimens. For this analysis, KS F ISO 137481-1 has been performed for 23 kinds of sandwich panels which mainly consist of EPS, PIR, PUR, Glass wool and so on. KS F ISO 13784-1 represents real scale reaction-to-fire test and focuses on measuring flashover phenomenon rather than other tests as like ISO 5660-1 and SBI.

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Study on the Real-Time Walking Control of a Humanoid Robot U sing Fuzzy Algorithm

  • Kong, Jung-Shik;Lee, Eung-Hyuk;Lee, Bo-Hee;Kim, Jin-Geol
    • International Journal of Control, Automation, and Systems
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    • v.6 no.4
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    • pp.551-558
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    • 2008
  • This paper deals with the real-time stable walking for a humanoid robot, ISHURO-II, on uneven terrain. A humanoid robot necessitates achieving posture stabilization since it has basic problems such as structural instability. In this paper, a stabilization algorithm is proposed using the ground reaction forces, which are measured using FSR (Force Sensing Resistor) sensors during walking, and the ground conditions are estimated from these data. From this information the robot selects the proper motion pattern and overcomes ground irregularities effectively. In order to generate the proper reaction under the various ground situations, a fuzzy algorithm is applied in finding the proper angle of the joint. The performance of the proposed algorithm is verified by simulation and walking experiments on a 24-DOFs humanoid robot, ISHURO-II.