• 제목/요약/키워드: Probes

검색결과 1,240건 처리시간 0.023초

고속 3차원 측정 및 칼라 이미징을 위한 다중 광탐침 공초점 주사 현미경 (Confocal Scanning Microscopy with Multiple Optical Probes for High Speed 3D Measurements and Color Imaging)

  • 천완희;이승우;안진우;권대갑
    • 반도체디스플레이기술학회지
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    • 제7권1호
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    • pp.11-16
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    • 2008
  • Confocal scanning microscopy is a widely used technique for three dimensional measurements because it is characterized by high resolution, high SNR and depth discrimination. Generally an image is generated by moving one optical probe that satisfies the confocal condition on the specimen. Measurement speed is limited by movement speed of the optical probe; scanning speed. To improve measurement speed we increase the number of optical probes. Specimen region to scan is divided by optical probes. Multi-point information each optical probe points to can be obtained simultaneously. Therefore image acquisition speed is increased in proportion to the number of optical probes. And multiple optical probes from red, green and blue laser sources can be used for color imaging and image quality, i.e., contrast, is improved by adding color information by this way. To conclude, this technique contributes to the improvement of measurement speed and image quality.

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Utilizing Natural and Engineered Peroxiredoxins As Intracellular Peroxide Reporters

  • Laer, Koen Van;Dick, Tobias P.
    • Molecules and Cells
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    • 제39권1호
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    • pp.46-52
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    • 2016
  • It is increasingly apparent that nature evolved peroxiredoxins not only as $H_2O_2$ scavengers but also as highly sensitive $H_2O_2$ sensors and signal transducers. Here we ask whether the $H_2O_2$ sensing role of Prx can be exploited to develop probes that allow to monitor intracellular $H_2O_2$ levels with unprecedented sensitivity. Indeed, simple gel shift assays visualizing the oxidation of endogenous 2-Cys peroxiredoxins have already been used to detect subtle changes in intracellular $H_2O_2$ concentration. The challenge however is to create a genetically encoded probe that offers real-time measurements of $H_2O_2$ levels in intact cells via the Prx oxidation state. We discuss potential design strategies for Prx-based probes based on either the redoxsensitive fluorophore roGFP or the conformation-sensitive fluorophore cpYFP. Furthermore, we outline the structural and chemical complexities which need to be addressed when using Prx as a sensing moiety for $H_2O_2$ probes. We suggest experimental strategies to investigate the influence of these complexities on probe behavior. In doing so, we hope to stimulate the development of Prx-based probes which may spearhead the further study of cellular $H_2O_2$ homeostasis and Prx signaling.

Molecular Tension Probes to Quantify Cell-Generated Mechanical Forces

  • Baek, Kyung Yup;Kim, Seohyun;Koh, Hye Ran
    • Molecules and Cells
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    • 제45권1호
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    • pp.26-32
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    • 2022
  • Living cells generate, sense, and respond to mechanical forces through their interaction with neighboring cells or extracellular matrix, thereby regulating diverse cellular processes such as growth, motility, differentiation, and immune responses. Dysregulation of mechanosensitive signaling pathways is found associated with the development and progression of various diseases such as cancer. Yet, little is known about the mechanisms behind mechano-regulation, largely due to the limited availability of tools to study it at the molecular level. The recent development of molecular tension probes allows measurement of cellular forces exerted by single ligand-receptor interaction, which has helped in revealing the hitherto unknown mechanistic details of various mechanosensitive processes in living cells. Here, we provide an introductory overview of two methods based on molecular tension probes, tension gauge tether (TGT), and molecular tension fluorescence microscopy (MTFM). TGT utilizes the irreversible rupture of double-stranded DNA tether upon application of force in the piconewton (pN) range, whereas MTFM utilizes the reversible extension of molecular springs such as polymer or single-stranded DNA hairpin under applied pN forces. Specifically, the underlying principle of how molecular tension probes measure cell-generated mechanical forces and their applications to mechanosensitive biological processes are described.

Comparison of ECT Probes in Diagnosis of Defects

  • Mun, Ho-Young;Kim, Chang-Eob
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.190-196
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    • 2014
  • In this paper, the characteristics of a defective elliptical aluminum plate are analyzed by three different eddy current testing probes; T/R, T/T, and Impedance probes. The analysis was done by 3D finite element method, and the impedance change of real and imaginary voltage values were analyzed.

아리랑 1호에서의 야간 이온층 관측 (OBSERVATION OF NIGHTTIME IONOSPHERE USING KOMPSAT-l)

  • 이재진;민경욱;이은상;김준
    • 천문학논총
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    • 제15권spc2호
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    • pp.37-44
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    • 2000
  • Two different types of plasma probes have been developed and are currently in operation on board the KOMPSAT-l. One is the cylindrical Langmuir Probe (LP) that measures the electron density and temperature from its current-voltage characteristics in thermal plasmas, and the other is the Electron Temperature Sensor (ETS) which directly gives the information of the ambient electron temperatures. These plasma probes provide the electron properties of the local nighttime ionosphere at the KOMPSAT-l altitudes. In this paper we briefly describe the probes and the initial results obtained from these probes since the beginning of their normal operation in April, 2000.

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Universal-, Genus-specific, Species-specific Probes and Primers Design for Microbial Identification

  • Park, Jun-Hyung;Park, Hee-Kyung;Song, Eunsil;Jang, Hyun-Jung;Kang, Byeong-Chul;Lee, Seung-Won;Kim, Hyun-Jin;Kim, Cheol-Min
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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    • pp.399-401
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    • 2005
  • MIPROBE is a web-based tool for design of universal, genus-specific, and species-specific primers and probes. The main functions of MIPROBE are collection of target gene sequences, construction of consensus sequences, collection of candidate primers and probes, and evaluation of candidates by BLAST. Biologists with little computer skills can easily use MIPROBE to design large-scale universal, genus-, and species-specific primers and probes. This software is available at http://www.miprobe.com. Also detailed descriptions of how to use the program are found at this site.

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Highly Sensitive PNA Array Platform Technology for Single Nucleotide Mismatch Discrimination

  • Choi, Jae-Jin;Jang, Min-Jeong;Kim, Ji-Hyun;Park, Hee-Kyung
    • Journal of Microbiology and Biotechnology
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    • 제20권2호
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    • pp.287-293
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    • 2010
  • Reliable discrimination of a single nucleotide mismatch was demonstrated using arrays with peptide nucleic acid (PNA) probes. The newly developed PNA probes immobilization method and hybridization conditions for PNA arrays gave excellent specificity and sensitivity. In addition we compared the specificity, sensitivity, and stability obtained with the PNA and DNA arrays in discriminating single nucleotide mismatches. The PNA arrays had superior perfect match-to-mismatch signal ratios and sensitivities. The relative signal intensities of mismatch PNA probes ranged from 1.6% to 12.1% of the perfect-match PNA probes. These results demonstrated that the PNA arrays were 2.0 to 37.3 times more specific and about 10 times more sensitive than DNA arrays. The PNA array showed the same specificity and sensitivity after 12-month storage at room temperature.

The targeting peptides for tumor receptor imaging

  • Yim, Min Su;Ryu, Eun Kyoung
    • 대한방사성의약품학회지
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    • 제2권2호
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    • pp.63-68
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    • 2016
  • Peptides have been developed for in vivo imaging probes against to the specific biomarker in the biological process of living systems. Peptide based imaging probes have been applied to identify and detect their active sites using imaging modalities, such as PET, SPECT and MRI. Especially, tumor receptor imaging with the peptides has been widely used to specific tumor detection. This review discusses the targeting peptides that have been successfully characterized for tumor diagnosis by receptor imaging.

Development of Array-based Technology for Detection of HAV Using Gold-DNA Probes

  • Wan, Zhixiang;Wang, Yefu;Li, Shawn Shun-Cheng;Duan, Lianlian;Zhai, Jianxin
    • BMB Reports
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    • 제38권4호
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    • pp.399-406
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    • 2005
  • A sensitive method for detection of Hepatitis A virus (HAV) by utilizing gold-DNA probe on an array was developed. Amino- modified oligodeoxynucleotides at the 5' position were arrayed on an activated glass surface to function as capture probes. Sandwich hybridization occurred among capture probes, the HAV amplicon, and gold nanoparticle-supported oligonucleotide probes. After a silver enhancement step, signals were detected by a standard flatbed scanner or just by naked eyes. As little as 100 fM of HAV amplicon could be detected on the array. Therefore, the array technology is an alternative to be applied in detection of HAV due to its low-cost and high-sensitivity.

Detection of Virulence-Associated Genes in Clinical Isolates of Bacillus anthracis by Multiplex PCR and DNA Probes

  • Kumar, Sanjay;Tuteja, Urmil
    • Journal of Microbiology and Biotechnology
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    • 제19권11호
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    • pp.1475-1481
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    • 2009
  • Anthrax is a zoonotic disease caused by Bacillus anthracis, and well recognized as a potential agent for bioterrorism. B. anthracis can be identified by detecting the virulence factors genes located on two plasmids, pXO1 and pXO2. The aim of the present study was to determine the presence of virulence genes in 27 isolates of B. anthracis isolated from clinical and environmental samples. For this purpose, multiplex PCR and DNA probes were designed to detect protective antigen (pag), edema factor (cya), lethal factor (lef), and capsule (cap) genes. Our results indicated that all the isolates contained all the above virulence genes, suggesting that the isolates were virulent. To the best our knowledge, this is the first study about the determination of virulence marker genes in clinical and environmental isolates of B. anthracis using multiplex PCR and DNA probes in India. We suggest that the above methods can be useful in specific identification of virulent B. anthracis in clinical and environmental samples.