• Title/Summary/Keyword: Oxygen generation

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Hydroxyzine Induces Cell Death in Triple-Negative Breast Cancer Cells via Mitochondrial Superoxide and Modulation of Jak2/STAT3 Signaling

  • Shakya, Rajina;Park, Gyu Hwan;Joo, Sang Hoon;Shim, Jung-Hyun;Choi, Joon-Seok
    • Biomolecules & Therapeutics
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    • v.30 no.6
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    • pp.585-592
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    • 2022
  • Treatment of triple-negative breast cancer (TNBC) has been limited due to the lack of molecular targets. In this study, we evaluated the cytotoxicity of hydroxyzine, a histamine H1 receptor antagonist in human triple-negative breast cancer BT-20 and HCC-70 cells. Hydroxyzine inhibited the growth of cells in dose- and time-dependent manners. The annexin V/propidium iodide double staining assay showed that hydroxyzine induced apoptosis. The hydroxyzine-induced apoptosis was accompanied down-regulation of cyclins and CDKs, as well as the generation of reactive oxygen species (ROS) without cell cycle arrest. The effect of hydroxyzine on the induction of ROS and apoptosis on TNBC cells was prevented by pre-treatment with ROS scavengers, N-acetyl cysteine or Mito-TEMPO, a mitochondria-targeted antioxidant, indicating that an increase in the generation of ROS mediated the apoptosis induced by hydroxyzine. Western blot analysis showed that hydroxyzine-induced apoptosis was through down-regulation of the phosphorylation of JAK2 and STAT3 by hydroxyzine treatment. In addition, hydroxyzine induced the phosphorylation of JNK and p38 MAPK. Our results indicate that hydroxyzine induced apoptosis via mitochondrial superoxide generation and the suppression of JAK2/STAT3 signaling.

The Influence of Silicon Doping on Electrical Characteristics of Solution Processed Silicon Zinc Tin Oxide Thin Film Transistor

  • Lee, Sang Yeol;Choi, Jun Young
    • Transactions on Electrical and Electronic Materials
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    • v.16 no.2
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    • pp.103-105
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    • 2015
  • Effect of silicon doping into ZnSnO systems was investigated using solution process. Addition of silicon was used to suppress oxygen vacancy generation. The transfer characteristics of the device showed threshold voltage shift toward the positive direction with increasing Si content due to the high binding energy of silicon atoms with oxygen. As a result, the carrier concentration was decreased with increasing Si content.

Arachidonic Acid Liberated through Activation of $iPLA_2$ Mediates the Production of Reactive Oxygen Species and Apoptosis Induced by N-Ethylmaleimide in HepG2 Human Hepatoma Cells

  • Lee, Yong-Soo
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.242.2-243
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    • 2002
  • We have previously reported that activation of $K^{+}$-$Cl^{-}$-cotransport (KCC) by N-ethylmaleimide (NEM) induces apoptosis through generation of reactive oxygen species (ROS) in HepG2 human hepatoblastoma cells. In this study we investigated the possible role of phospholipase $A_2$($PLA_2$)-arachidonic acid (AA) signals in the mechanism of the NEM actions. (omitted)

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Synthesis of Selenoflavonoids

  • Kim, Dong-Myung;Jeong, Jin-Hyun
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.182.1-182.1
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    • 2003
  • Flavonoids with oxygen atoms are known to have potent biological effect.They have been studied long as major antioxidants which protect cell membranes. Recent medical surveys show that increased intake of selenium decreases the risk of breast, colon, lung and prostrate cancer by preventing free radical generation. The flavonoids, isoflavonoids, and coumarins which form the bulk of these compounds are very polar and have limited use as drugs which have to pass through BBB(Brain Blood Barrier)The non-polar property is increased by exchange oxygen to selenium as a part of heterocyclic compound. (omitted)

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Reactivity and Attrition Resistance of Three Oxygen Carrier Particles for Chemical-Looping Combustor (매체순환식 가스연소기 적용을 위한 세 가지 산소공여입자들의 반응성 및 내마모성)

  • Ryu, Ho-Jung;Jin, Gyoung-Tae
    • Journal of Hydrogen and New Energy
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    • v.15 no.3
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    • pp.208-219
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    • 2004
  • To find a suitable oxygen carrier particle for a 50kW chemical-looping combustor, which was designed and installed to demonstrate continuous oxidation and reduction, three oxygen carrier particles(NiO/bentonite, $NiO/NiAl_2O_4$, $CoO_x/CoAl_2O_4$) were prepared. The reactivity and the attrition resistance of particles were measured and investigated by a thermo-gravimetrical analyzer and an attrition test apparatus respectively. From the viewpoints of oxygen transfer capacity, optimum reaction temperature(operating temperature range), reaction rate, carbon deposition rate, and attrition resistance, NiO/bentonite particle showed better performance than the other particles, therefore we selected NiO/bentonite particle as an optimum oxygen carrier particle.

Measurement of Heat Release Rate by Carbon Dioxide Generation Method for Methane Fire (메탄화재의 이산화탄소 생성법에 의한 화재발열량 측정)

  • Kim, Sung-Chan
    • Fire Science and Engineering
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    • v.34 no.2
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    • pp.1-6
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    • 2020
  • The energy released by various burning material has a wide range of its magnitude and transient characteristics, the measurement of the heat release rate(HRR) has been considered as one of the most challenging issue among the parameters related to fire. This study compares the measured HRR calculated by the oxygen consumption (OC) method and the carbon dioxide generation (CDG) method using a laboratory-scale fire calorimeter. The feasibility of the CDG method is examined by analyzing the relative error. The relationship between the oxygen depletion factor and CO2 mass flow rate, which is a key parameter in HRR calculations, showed strong linearity at 6 % for the methane burner fire. The contribution of HRR by CO was less than 7% compared with the of HRR by CO2 in the CDG calculation method. The linearity of the OC and CDG methods with respect to HRR of the referenced methane burner in a quasi-steady state was less than 1%; this indicates that the CDG method can be utilized as a complementary method in heat release rate measurement.

Generation of Reactive Oxygen Species Contributes to the Development of Carbon Black Cytotoxicity to Vascular Cells

  • Lee, Jong-Gwan;Noh, Won-Jun;Kim, Hwa;Lee, Moo-Yeol
    • Toxicological Research
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    • v.27 no.3
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    • pp.161-166
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    • 2011
  • Carbon black, a particulate form of pure elemental carbon, is an industrial chemical with the high potential of occupational exposure. Although the relationship between exposure to particulate matters (PM) and cardiovascular diseases is well established, the cardiovascular risk of carbon black has not been characterized clearly. In this study, the cytotoxicity of carbon black to vascular smooth muscle and endothelial cells were examined to investigate the potential vascular toxicity of carbon black. Carbon black with distinct particle size, N330 (primary size, 28~36 nm) and N990 (250~350 nm) were treated to A-10, rat aortic smooth muscle cells and human umbilical vein endothelial cell line, ECV304, and cell viability was assessed by lactate dehydrogenase (LDH) leakage assay. Treatment of carbon black N990 resulted in the significant reduction of viability in A-10 cells at 100 ${\mu}g$/ml, the highest concentration tested, while N330 failed to cause cell death. Cytotoxicity to ECV304 cells was induced only by N330 at higher concentration, 200 ${\mu}g$/ml, suggesting that ECV304 cells were relatively resistant to carbon black. Treatment of 100 ${\mu}g$/ml N990 led to the elevation of reactive oxygen species (ROS) detected by dichlorodihydrofluorescein (DCF) in A-10 cells. Pretreatment of antioxidants, N-acetylcysteine (NAC) and sulforaphane restored decreased viability of N990-treated A-10 cells, and N-acetylcysteine, but not sulforaphane, attenuated N990-induced ROS generation in A-10 cells. Taken together, present study shows that carbon black is cytotoxic to vascular cells, and the generation of reactive oxygen contributes to the development of cytotoxicity. ROS scavenging antioxidant could be a potential strategy to attenuate the toxicity induced by carbon black exposure.