• Title/Summary/Keyword: Oxygen membrane

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A Study on the Oxidative Damage Induced by UVB Irradiation to Mouse Skin (UVB 조사로 인한 마우스 피부조직의 산화적 손상)

  • Rhie Sung-Ja;Kim Young-Chul
    • Environmental Analysis Health and Toxicology
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    • v.21 no.2 s.53
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    • pp.165-172
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    • 2006
  • The backs with a hair cut of 6-week-old healthy ICR male mice were once exposed to a dose of $400mJ/cm^2$ UVB. An acute dermal inflammation was observed, and the inflamed skins were almost completely cured after 6 days of the exposure. At 24 hours after exposure, the epidermal keratinocytes showed a cell-membrane damage with the destruction of intercellular junctions, agglutination of tonofilaments within the cytoplasm and nucleus damage. The activity of XO showed a significant increase (p<0.05) in up to 144 hours. The activities of CAT and SOD showed a significant decrease (p<0.05) in up to 96 hours, but they were not significantly different from the normal value at 144 hours. The GST activity was significantly decreased (p<0.01) in up to 96 hours, not so at 24 hours. However, that was not significantly different from the normal value at 144 hours. There was a significant decrease (p<0.01) in the contents of TBARS at 48 and 96 hours, without any significant difference at 144 hours. While the content of GSH was significantly lower (p<0.05) at 24 hours, that was not significantly different thereafter up to 144 hours from the normal value. Therefore, it is assumed that skin damage with a dose of $400mJ/cm^2$ UVB irradiation might be caused by the oxidative stress which was resulted from the unbalance of oxygen fret radical generating and scavenging enzymes.

Measurement of oxygen isotope ratio using tunable diode laser absorption spectroscopy (다이오드 레이저 흡수분광법을 이용한 산소 동위원소의 성분비 측정)

  • Park, Sang-Eon;Jung, Do-Young;Kim, Jae-Woo;Ko, Kwang-Hoon;Im, Kwon;Jung, Eui-Chang;Kim, Chul-Joong
    • Korean Journal of Optics and Photonics
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    • v.15 no.1
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    • pp.1-5
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    • 2004
  • Tunable diode laser absorption spectroscopy was performed for analysis of the H$_2$$^{18}$ O/H$_2$$^{16}$ O isotope ratio of a water sample which was enriched by the membrane distillation method. In order to improve the signal-to-noise ratio, the wavelength modulation spectroscopic method was used with a lock-in amplifier. The fringe noise could be suppressed by using the FFT (Fast Fourier Transform) lowpass filter and the optimization of the modulation depth of the laser frequency. The maximum deviation of $\delta$-value was measured to be$\pm$4$\textperthousand$.

Magnetic Properties and Electronic Structure of $Pt_3Ni$ (001), (110) and (111) Surfaces: Density Functional Study

  • Kumar, Sharma Bharat;Kwon, O-Ryong;Odkhuu, Dorj;Hong, Soon-Cheol
    • Proceedings of the Korean Magnestics Society Conference
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    • 2011.06a
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    • pp.129-129
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    • 2011
  • The limited understanding of the surface properties of $Pt_3Ni$ for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cell (PEMFC) has motivated the study of properties and electronic structures of seven layered $Pt_3Ni$ (001), (110), and (111) surfaces. The first principle method based on density functional theory (DFT) is carried out. It is found that the bulk $Pt_3Ni$ has a ferromagnetic ground state with the ordered fcc type L12 structure, which is in good agreement with other results. Non magnetic Pt has the induced magnetic moment due to the strong hybridization between 3d Ni and 5d Pt. The magnetic moment of Pt and Ni enhanced on the surface of each due to surface effect however the magnetic moment of surface Pt in the Pt-segregated Pt3Ni (111) decreased and the magnetic moment of Ni in Ni rich subsurface increased significantly. The calculated d band centers of Pt explain the possibilities for oxygen absorption and play the important roles in altering the catalytic properties. The spin polarized densities of states are presented in order to understand physical properties of Pt in different surfaces in detail.

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Antioxidant Activity of Seaweed Extracts from Kongsfjorden, an Inlet in the Arctic's Svalbard Archipelago (북극 스발바드 군도 콩스피요르드에서 채집한 해조류 추출물의 항산화 활성)

  • Lee, Jung-Im;Kim, You-Ah;Kong, Chang-Suk;Yea, Sung-Su;Han, Tae-Jun;Kang, Sung-Ho;Kim, Jee-Hee;Seo, Young-Wan
    • Ocean and Polar Research
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    • v.31 no.2
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    • pp.213-218
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    • 2009
  • We examined the intracellular antioxidative effects of 20 Arctic seaweed extracts in Raw 264.7 cells. Each seaweed species was subjected to extraction using acetone/dichloromethane and methanol, respectively, after which the extracts were combined and used as the test sample. The antioxidant ability of all 20 seaweeds extracts was evaluated using four different activity tests, including the degree of occurrence of intracellular reactive oxygen species (ROS), $ONOO^-$, and lipid peroxidation in Raw 264.7 cells, as well as the extent of oxidative damage of genomic DNA purified from Raw 264.7 cells. Crude extracts from Monostroma obscurum, Alaria esculnta, Laminaria digitata, Desmarestia aculeata, Chorda filum, Ptilota seriata, Phycidrys rubens, Devaleraea ramentacea and Palmaria palmata exhibited significant scavenging effects on the generation of intracellular ROS. Among them, Monostroma obscurum and Phycidrys rubens significantly inhibited membrane lipid peroxidation and DNA oxidation. Moreover, Phycidrys rubens exhibited scavenging effects on peroxynitrite generated from SIN-1.

A Benzylideneacetophenone Derivative Induces Apoptosis of Radiation-Resistant Human Breast Cancer Cells via Oxidative Stress

  • Park, Jeong Eon;Piao, Mei Jing;Kang, Kyoung Ah;Shilnikova, Kristina;Hyun, Yu Jae;Oh, Sei Kwan;Jeong, Yong Joo;Chae, Sungwook;Hyun, Jin Won
    • Biomolecules & Therapeutics
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    • v.25 no.4
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    • pp.404-410
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    • 2017
  • Benzylideneacetophenone derivative (1E)-1-(4-hydroxy-3-methoxyphenyl) hept-1-en-3-one (JC3) elicited cytotoxic effects on MDA-MB 231 human breast cancer cells-radiation resistant cells (MDA-MB 231-RR), in a dose-dependent manner, with an $IC_{50}$ value of $6{\mu}M$ JC3. JC3-mediated apoptosis was confirmed by increase in sub-G1 cell population. JC3 disrupted the mitochondrial membrane potential, and reduced expression of anti-apoptotic B cell lymphoma-2 protein, whereas it increased expression of pro-apoptotic Bcl-2-associated X protein, leading to the cleavage of caspase-9, caspase-3 and poly (ADP-ribose) polymerase. In addition, JC3 activated mitogen-activated protein kinases, and specific inhibitors of these kinases abrogated the JC3-induced increase in apoptotic bodies. JC3 increased the level of intracellular reactive oxygen species and enhanced oxidative macromolecular damage via lipid peroxidation, protein carbonylation, and DNA strand breakage. Considering these findings, JC3 is an effective therapy against radiation-resistant human breast cancer cells.

Morus alba Accumulates Reactive Oxygen Species to Initiate Apoptosis via FOXO-Caspase 3-Dependent Pathway in Neuroblastoma Cells

  • Kwon, Young Hwi;Bishayee, Kausik;Rahman, Md. Ataur;Hong, Jae Seung;Lim, Soon-Sung;Huh, Sung-Oh
    • Molecules and Cells
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    • v.38 no.7
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    • pp.630-637
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    • 2015
  • Morus alba root extract (MARE) has been used to treat hyperglycaemic conditions in oriental medicine. Here, we studied whether MARE possesses a cytotoxic effect on neuroblastoma. To check the cytotoxicity generated by MARE was whether relatively higher against the cancer cells rather than normal cells, we chose a neuroblastoma cell line (B103) and a normal cell line (Rat-2). A CCK assay revealed that MARE ($10{\mu}g/ml$) reduced cell viability to approximately 60% compared to an untreated control in B103 cells. But in Rat-2 cells, MARE induced relatively lower cytotoxicity. To investigate the mechanisms underlying the cytotoxic effect of MARE, we used flow cytometry combined with immunoblot analyses. We found that MARE-treatment could accumulate ROS and depolarize mitochondria membrane potential of B103 cells. Further treatment with MARE in B103 cells also could damage DNA and induce apoptosis. An expression study of p-Akt also suggested that there was a reduction in cellular proliferation and transcription along with the process of apoptosis, which was further evidenced by an increase in Bax and cleaved-caspase 3 activity. Together, our findings suggest that MARE produces more cytotoxicity in cancer cells while having a relatively attenuated effect on normal cells. As such, MARE may be a safer option in cancer therapeutics, and it also shows potential for the patients with symptoms of hyperglycemia and cancer.

Simultaneous Determination of Glucose and Ethanol of Takju by Biosensor using Dual Cathode Electrode (Dual Cathode Electrode를 이용한 바이오센서로 탁주 중의 포도당 및 에탄올의 동시 측정)

  • Park, In-Seon;Kim, Jung-Ho;Kim, Tae-Jin;Kim, Nam-Soo;Noh, Bong-Soo
    • Korean Journal of Food Science and Technology
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    • v.28 no.5
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    • pp.974-980
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    • 1996
  • A biosensor was prepared with dual cathode electrode and immobilized enzyme membrane. A nylon net was used for the immobilization of glucose oxidase and alcohol oxidase. The immobilized enzymes were placed on the surface of the electrode which was prepared with one anode and two cathodes as an oxygen electrode. The determination of components by the biosensor was based on the consumption of dissolved oxygen. The optimum condition of this system was 0.1 M potassium phosphate buffer solution, pH 7.5 at $35^{\circ}C$. Glucose and ethanol in takju were simultaneously determined by the biosensor. Comparing with UV-spectrophotometer and gas chromatograph for cross checking, there was a good correlation between the biosensor and the conventional methods. Biosensor with dual cathode electrode required no clarification or pretreatments. It was used for simultaneous determination of glucose and ethanol during the fermentation of takju.

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Maintenance of Sperm Characteristics and In vitro Developmental Rate of Embryos against Oxidative Stress through Antioxidants in Pig

  • Jang, H.Y.;Kong, H.S.;Oh, J.D.;Park, B.K.;Yang, B.K.;Jeon, G.J.;Lee, H.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.3
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    • pp.340-345
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    • 2008
  • Oxidative stress is one of the major causes of failure of in vitro storage of boar semen. Reactive oxygen species (ROS) are one of the important mediators of oxidative stress during in vitro storage of boar semen. Our study examined the effects of taurine on sperm characteristic and on in vitro developmental embryos during in vitro storage of boar semen for 7 days. Semen was randomly aliquoted into 3 centrifuge tubes and treated with different concentrations of taurine (25-100 mM). The characteristics of boar sperm were analyzed for motility by light microscopy, viability by using a Makler counting chamber and membrane integrity by a hypoosmotic swelling test (HOST). The percentages of motile spermatozoa in taurine groups after 5 days were significantly higher compared to the control. Sperm viability in the control was lower than in taurine groups after 7 days irrespective of different taurine concentration. In the hyoosmotic swelling test (HOST), significantly higher results were obtained in taurine groups after 3 days. Also, the developmental rates of IVM/IVF porcine embryos from semen treated with pyruvate and taurine were significantly increased when compared with the control (p<0.05). These results indicate that supplementation of taurine as an antioxidant in boar semen extender can improve the semen quality.

Dissolved organic matter characteristics and bacteriological changes during phosphorus removal using ladle furnace slag

  • Noh, Jin H.;Lee, Sang-Hyup;Choi, Jae-Woo;Maeng, Sung Kyu
    • Membrane and Water Treatment
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    • v.9 no.3
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    • pp.181-188
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    • 2018
  • A sidestream contains the filtrate or concentrate from the belt filter press, filter backwash and supernatant from sludge digesters. The sidestream flow, which heads back into the sewage treatment train, is about 1-3% less than the influent flow. However, the sidestream can increase the nutrient load since it contains high concentrations of phosphorus and nitrogen. In this study, the removal of PO4-P with organic matter characteristics and bacteriological changes during the sidestream treatment via ladle furnace (LF) slag was investigated. The sidestream used in this study consisted of 11-14% PO4-P and 3.2-3.6% soluble chemical oxygen demand in influent loading rates. LF slag, which had a relatively high $Ca^{2+}$ release compared to other slags, was used to remove $PO_4-P$ from the sidestream. The phosphate removal rates increased as the slag particle size decreased 19.1% (2.0-4.0 mm, 25.2% (1.0-2.0 mm) and 79.9% (0.5-1.0 mm). The removal rates of dissolved organic carbon, soluble chemical oxygen demand, color and aromatic organic matter ($UV_{254}$) were 17.6, 41.7, 90.2 and 77.3%, respectively. Fluorescence excitation-emission matrices and liquid chromatography-organic carbon detection demonstrated that the sidestream treatment via LF slag was effective in the removal of biopolymers. However, the removal of dissolved organic matter was not significant during the treatment. The intact bacterial biomass decreased from $1.64{\times}10^8cells/mL$ to $1.05{\times}10^8cells/mL$. The use of LF slag was effective for the removal of phosphate and the removal efficiency of phosphate was greater than 80% for up to 100 bed volumes.

Relative Apoptosis-inducing Potential of Homeopathic Condurango 6C and 30C in H460 Lung Cancer Cells In vitro -Apoptosis-induction by homeopathic Condurango in H460 cells-

  • Sikdar, Sourav;Saha, Santu Kumar;Khuda-Bukhsh, Anisur Rahman
    • Journal of Pharmacopuncture
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    • v.17 no.1
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    • pp.59-69
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    • 2014
  • Objectives: In homeopathy, it is claimed that more homeopathically-diluted potencies render more protective/curative effects against any disease condition. Potentized forms of Condurango are used successfully to treat digestive problems, as well as esophageal and stomach cancers. However, the comparative efficacies of Condurango 6C and 30C, one diluted below and one above Avogadro's limit (lacking original drug molecule), respectively, have not been critically analyzed for their cell-killing (apoptosis) efficacy against lung cancer cells in vitro, and signalling cascades have not been studied. Hence, the present study was undertaken. Methods: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were conducted on H460-non-small-cell lung cancer (NSCLC) cells by using a succussed ethyl alcohol vehicle (placebo) as a control. Studies on cellular morphology, cell cycle regulation, generation of reactive oxygen species (ROS), changes in mitochondrial membrane potential (MMP), and DNA-damage were made, and expressions of related signaling markers were studied. The observations were done in a "blinded" manner. Results: Both Condurango 6C and 30C induced apoptosis via cell cycle arrest at subG0/G1 and altered expressions of certain apoptotic markers significantly in H460 cells. The drugs induced oxidative stress through ROS elevation and MMP depolarization at 18-24 hours. These events presumably activated a caspase-3-mediated signalling cascade, as evidenced by reverse transcriptase-polymerase chain reaction (RT-PCR), western blot and immunofluorescence studies at a late phase (48 hours) in which cells were pushed towards apoptosis. Conclusion: Condurango 30C had greater apoptotic effect than Condurango 6C as claimed in the homeopathic doctrine.