• Title/Summary/Keyword: Biological assay

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An electrochemical functional assay for the sensing of nitric oxide release induced by angiogenic factors

  • Trouillon, Raphael;O'Hare, Danny;Chang, Soo-Ik
    • BMB Reports
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    • v.44 no.11
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    • pp.699-704
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    • 2011
  • Nitric oxide (NO) is a critical biological mediator involved in numerous diseases. However, the short lifetime of this molecule in biological conditions can make its study in situ complicated. Here, we review some recent results on the role of NO in angiogenesis, obtained using a biocompatible microelectrode array. This simple system allowed for the quick and easy quantification of NO released from cells grown directly on the surface of the sensor. We have used this technology to demonstrate that angiogenin induces NO release, and to partially elucidate its intracellular transduction pathway.

The Current Status and Future Outlook of Quantum Dot-Based Biosensors for Plant Virus Detection

  • Hong, Sungyeap;Lee, Cheolho
    • The Plant Pathology Journal
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    • v.34 no.2
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    • pp.85-92
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    • 2018
  • Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), widely used for the detection of plant viruses, are not easily performed, resulting in a demand for an innovative and more efficient diagnostic method. This paper summarizes the characteristics and research trends of biosensors focusing on the physicochemical properties of both interface elements and bioconjugates. In particular, the topological and photophysical properties of quantum dots (QDs) are discussed, along with QD-based biosensors and their practical applications. The QD-based Fluorescence Resonance Energy Transfer (FRET) genosensor, most widely used in the biomolecule detection fields, and QD-based nanosensor for Rev-RRE interaction assay are presented as examples. In recent years, QD-based biosensors have emerged as a new class of sensor and are expected to open opportunities in plant virus detection, but as yet there have been very few practical applications (Table 3). In this article, the details of those cases and their significance for the future of plant virus detection will be discussed.

Antioxidative and Protective Activity of Polysaccharide Extract from Artemisia iwayomogi Kitamura Stems on UVB-Damaged Mouse Epidermis

  • Ahn, Byung-Yong;Jung, Mun-Yhung
    • Journal of Applied Biological Chemistry
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    • v.54 no.3
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    • pp.184-189
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    • 2011
  • Polysaccharide (PS) was fractionated from hot-water extract of Artemisia iwayomogi Kitamura stems. PS showed considerably higher hydroxyl radical scavenging activity than caffeic acid and glutathione. PS showed lower superoxide anion radical scavenging activity than hydroquinone and ascorbic acid. The scavenging activity of PS on the reactive oxygen species (ROS) induced by human neutrophils with zymosan was determined by the lucigenin-enhanced chemiluminescence assay. The scavenging effect of the PS on ROS as determined by the chemiluminescence assay was about 2-fold stronger than that of ascorbic acid at the same concentration. PS significantly decreased protein carbonyl and malonaldehyde contents in UVB irradiated skin homogenates, which was comparable to glutathione at the same concentration. This result suggested that PS derived from A. iwayomogi Kitamura stems may be a potent candidate as functional compound for the protection on UVB induced skin damage in cosmetics.

An Assay Method with Lamina Joints of Korean Rice (우리나라 벼의 Lamima Joint를 이용한 생물검정법)

  • Park, Keun-Hyung;Hyun, Kyu-Hawn;Kim, Dong-Youn
    • Applied Biological Chemistry
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    • v.29 no.1
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    • pp.22-28
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    • 1986
  • To establish the bioassay system not only for brassinosteroids and auxins but also for growth retardants with the lamina joints of rice, excellent domestic cultivars were selected and affectable factors, condition of test material, pH, temperature, concentration of test solution, coexisting metallic ions ana combination with growth regulators, on the assay system were discussed.

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Microbead-based bio-assay using quantum dot fluorescence in a microfluidic chip (미소유체 칩 상에서 Quantum Dot 및 마이크로 비드를 이용한 생체물질 분석)

  • Yun, Kwang-Seok;Lee, Do-Hoon;Kim, Hak-Sung;Yoon, Eui-Sik
    • Journal of Sensor Science and Technology
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    • v.14 no.5
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    • pp.308-312
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    • 2005
  • We present a microfluidic chip designed for the detection of antibody by using quantum dots fluorescence and a microbead-based assay. A custom designed PDMS microfluidic chip with multi-layer channel is utilized for capturing microbeads; antibody injection into each micro-well; QD injection; and fluorescence detection. The experiment using the fabricated microfluidic chip has been performed on solutions with various concentrations of antibody and has shown correlated fluorescent intensities.

Cytotoxic Activity of Medicinal Plant Extracts against Human Tumor Cell Lines

  • Jeong, In-Hong;Lee, Jeong-Ock;Kim, Choul-Soo;Kim, Soo-Un;Ahn, Young-Joon
    • Journal of Applied Biological Chemistry
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    • v.43 no.1
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    • pp.59-61
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    • 2000
  • The cytotoxic activities of the methanol extracts of 44 plant species in 31 families against five human solid A549 (lung), SK-OV-2 (ovarian), SK-MEL-2 (melanoma), XF-498 (central nervous system), and HCT-15 (colon) tumor cell lines were examined using the sulforhodamine B (SRB) assay. Responses varied with both cell line and plant species used. Potent cytotoxic activities ($ED_{50}$, <$40{\mu}g/ml$) against all model tumor cell lines were produced from the extracts of Rhus chinensis gall (Galla rhois), Betula platyphylla var. japonica bark, Inula helenium root, Cinnamomum cassia bark, Cinnamomum sieboldii root bark, Lysimachia davurica whole plant, and Evodia rutaecarpa fruit. These plants may be useful for developing new types of naturally occurring anti-tumor agents.

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Effect of oral administration of Ginsenoside-Rb2 on rotavirus infection

  • Yoo, Yung-Choon;Lee, Kyung-Bok
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.276.2-276.2
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    • 2002
  • Glycosaminoglycans(PT -Gag) were isolated from the porcine testis. From the PT -Gag. we obtained two different types of Gag fractions using Dowex macroporous Resin MSA-1 column. PT-Gag-1.5% NaCl and PT -Gag-16% NaCl. Various biological activities of the GAGs were examined in aspect of anticoagulant and immunomodulating activity. The anticoagulant activity of the GAGs was evaluated by activated partial thromboplastin time (aPTT ) assay and thrombin time (TT) assay. The GAGs of porcine testis markedly increased the clotting times of both of aPTT and TT. showing that PT-Gag-16% NaCl was more effective than PT-Gag-1.5% NaCl. The immunomodulating activity of the GAGs was examined in relation to regulation of cytokine production of mutine peritoneal macrophages. Treatment with the GAGs promonently enhanced the prodution of cytokines. IFN-${\gamma}$, from macrophages. Taken together. GAGs isolated from porcine testis possess biological functions such as anticoagulant and immunomodulating activity.

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Searching of Possible Target Enzymes for Herbicide Development using Commercial Plant-Specific Inhibitors (식물 특정효소저해제의 생물활성 조사에 의한 신규제초제 작용점 탐색)

  • Hwan, In-Taek;Choi, Jung-Sup;Park, Sang-Hee;Lee, Kwan-Hwi;Lee, Byung-Hoi;Hong, Kyung-Sik;Cho, Kwang-Yun
    • The Korean Journal of Pesticide Science
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    • v.5 no.1
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    • pp.36-45
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    • 2001
  • This study was conducted to search new target enzymes of novel herbicide candidate. Total of 107 biochemical inhibitors reported to inhibit over than 100 different plant enzymes were purchased from commercial chemical companies. 15 inhibitors and 34 enzymes were selected by germination assay, seedling assay, wheat leaf disc assay, and whole plant assay. Among them, seven compounds of purine, phehyl-hydrazine, o-phenanthroline, oleylamine, dicyclohexylcarbodiimide, 7,8-benzoquinoline, and aminooxyacetic acid showed high herbicidal activity in the whole plant assay under greenhouse while 7,8-benzoquinone, 8-hydroxyquinoline, 2,2'-dipyridyl, and o-phenanthroline inhibited seed germination of barnyardgrass, rice, and tomato at concentrations of 1.25 to $5{\mu}M$. The compounds of 7,8-benzoquinoline, chlorpromazine, cyanuric fluoride, 4-methylpyrazole, oleylamine, tranylcypromine, and trifluoperazine inhibited the growth of cyanobacteria at 30 to $100{\mu}M$. The compounds of dicyclohexylcarbodiimide and chlorpromazine exhibited whitening effect on tile wheat leaf disc at $100{\mu}M$. These results suggest that the plant-specific enzyme inhibitors which have biological activities may supply the target enzyme for developing new herbicide candidate.

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Comparison of Biological Activities of Synurus deltoides (Aiton) Nakai Under Different Shading Conditions

  • Jiang, Yunyao;Noh, Heesum;Wang, Myeong-Hyeon
    • Korean Journal of Plant Resources
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    • v.26 no.6
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    • pp.686-694
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    • 2013
  • Shade treatment of Synurus deltoides (Aiton) Nakai was carried out with 0, 35, and 55% shading net, and samples were marked as no shade, 35% shade, and 55% shade, respectively. We examined in vitro antioxidant and anti-inflammatory capacities using a 1,1-diphenyl-2-2-pricylhydrazyl (DPPH) radical scavenging assay, a reducing power assay, a total antioxidant assay, a metal chelating assay, a superoxide radical scavenging assay, and a nitric oxide inhibition assay. As a result, no shade and 35% shade possessed higher DPPH radical scavenging activity and reducing power ability than that of 55% shade. Notably, no shade had significantly higher total phenolic and flavonoid contents than those in the other samples. No shade exhibited significantly higher total antioxidant activity than that of 35% shade and 55% shade. However, the chelating ability of 55% shade was significantly greater than that of no shade and 35% shade; 55% shade also showed significantly higher anti-inflammatory capacity than that of no shade or 35% shade.