• Title/Summary/Keyword: Reaction Oxygen

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Anticancer Effect of Houttuynia cordata Extract on Cancered ICR Mouse and L1210 Cells With Changes of SOD and GPx Activities (어성초 추출물의 ICR생쥐와 L1210 세포에 대한 항암작용 및 SOD, GPx 효소활성변화)

  • 하혜경;정대영;박시원
    • YAKHAK HOEJI
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    • v.48 no.4
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    • pp.219-225
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    • 2004
  • The present investigation was undertaken to examine the anticancer activity of the methanol extract from Houttuynia cordata on ICR mouse with induced abdominal cancer and L1210 cancer cells. When the methanol extract of Houttuynia cordata (10∼200 $\mu\textrm{g}$/$m\ell$) was administered orally to ICR mouse with abdominal cancer, 47.8% of the best life prolonging effect was obtained. In case of cytotoxicity study (inhibition of cell proliferation) of Houttuynia cordata extract against L1210 cells, $IC_{50}$/ was found to be 62.8 $\mu\textrm{g}$/$m\ell$. In contrast to such considerable toxicity against cancer cell line, the toxicity demonstrated by the identical extract against normal lymphocytes was very meagre as shown to be < 5% compared with 86.5% in case of L1210 cells at the same condition. To get an insight into the reaction mechanism undelying the anticancer activity, $O_2$ion quantity and antioxidant enzyme activities such as superoxide dismiutase (SOD) and glutathione peroxidase (GPx) of L1210 cells in the presence of Houttuynia cordata extract were measured. The increased values of SOD and GPx enzyme activities in addition to the augmented generation of $O_2$ ion in L1210 cells implied that the reactive oxygen species induding $O_2$ion which were presumably induced by Houttuynia cordata extract might have participated in the process of L1210 cells cytotoxicity.

A Study on Rescue of the Human Life against the Fire in the High-rise Building (고층건물 화재시 인명구조 방법에 관한 연구)

  • Choi, Kwon-Joong
    • Korean Security Journal
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    • no.5
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    • pp.309-325
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    • 2002
  • It was because mankind could use the fire that we have been civilized. creating a brilliant culture and developing an industrial society. While fire is very useful to our life, the number of the victims of fire continues to increase, This study suggests the ways to rescue the people safely when they are subject to a fire in a high-rise building. To this end, the concept of fire is reviewed. Fire breaks out when the conditions for congestion are met, and therefore. if any of the conditions can be blocked, the fire will be extinguished. In other words. the knowledge of such conditions will greatly help the fire fighters to rescue the people, and so. such conditions for congestion as flammable, heat, oxygen and chain reaction are examined. In addition, the effects of such by-products of fire as heat and smoke on human body are reviewed. In order to rescue the people more safely, the fire fighters are requested to review the situation and design a rescue strategy before being engaged in a full-scale rescue activity. This study discusses various rescue methods using such passages or equipments as stair case, double ladder, special fire fighting vehicle, elevator, jumar, rope, helicopter, etc. In conclusion. since it is more difficult to rescue the people from a high-rise building than from the ground, it is essential to design a rescue program not after fire but before it and thereby, minimize the number of victims.

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Experimental Study of Homotransplantation of Lung in Dogs (폐장이식에 관한 실험적 연구)

  • 김진식
    • Journal of Chest Surgery
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    • v.2 no.1
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    • pp.25-40
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    • 1969
  • Lung homotransplantation was performed in 15 pairs of dog. Methotrexate and R.E.S. blocking were used to prolong the survival time. Details of handling the transplant, operative technique and management of the recipient were discussed and following results were obtained: 1]. 7 dogs out of 15 dogs of homotransplantation of lung were survived beyond 3 days. In the group of dogs treated with methotrexate, the average survival was 8.5 days, and in the group of dogs treated with R.E.S. blocking, the average survial was 9.7 days with longest survival of 17 days. 2]. The causes of immediate postoperative death in homotransplantation of dogs were lung edema and disruption of bronchial anastomosis. 3]. The main causes of death in successful homotransplantation dogs which were survived beyond 3 days were infection of lung parenchyma and bronchial necrosis rather than the occurence of graft rejection. 4]. Graft rejection was not revealed even after 7 days of operation in the group treated with methotrexate as well as in the group treated with R. E.S. blocking. This finding made it suggest that the R. E.S. blocking may be effective to control the rejection reaction. 5]. Even though the pulmonary function of transplanted lung was revealed the evidence of severe impairment immediate after operation by bronchospirometry, it was increased gradually and 10 days after operation the minute ventilation and oxygen uptake were decreased 8%, 13% respectively less than pre-operative one.

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Reactive ion etching of InP using $BCl_3/O_2/Ar$ inductively coupled plasma ($BCl_3/O_2/Ar$ 유도결합 플라즈마를 이용한 InP의 건식 식각에 관한 연구)

  • 이병택;박철희;김성대;김호성
    • Journal of the Korean Vacuum Society
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    • v.8 no.4B
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    • pp.541-547
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    • 1999
  • Reactive ion etching process for InP using BCl3/O2/Ar high density inductively coupled plasma was investigated. The experimental design method proposed by the Taguchi was utilized to cover the whole parameter range while maintaining reasonable number of actual experiments. Results showed that the ICP power and the chamber pressure were the two dominant parameters affectsing etch results. It was also observed that the etch rate decreased and the surface roughness improved as the ICP power and the bias voltage increased and as the chamber pressure decreased. The Addition of oxygen to the gas mixture drastically improved surface roughness by suppressing the formation of the surface reaction product. The optimum condition was ICP power 600W, bias voltage -100V, 10% $O_2$, 6mTorr, and $180^{\circ}C$, resulting in about 0.15$\mu\textrm{m}$ etch rate with smooth surfaces and vertical mesa sidewalls Also, the maximum etch rate of abut 4.5 $\mu\textrm{m}$/min was obtained at the condition of ICP power 800W, bias voltage -150V, 15% $O_2$, 8mTorr and $160^{\circ}C$.

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Manganese Superoxide Dismutase (MnSOD Val-9Ala) Gene Polymorphism and Susceptibility to Gastric Cancer

  • Moradi, Mohammad-Taher;Yari, Kheirollah;Rahimi, Zohreh;Kazemi, Elham;Shahbazi, Mehrdad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.2
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    • pp.485-488
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    • 2015
  • Background: Oxidative stress caused by the generation of reactive oxygen species plays an important role in human carcinogenesis. Manganese superoxide dismutase (MnSOD) Val-9Ala in the mitochondrial target sequence is the best known polymorphism of this enzyme. The purpose of the current research was to assess the association of MnSOD Val-9Ala genotypes with the risk of gastric cancer. Materials and Methods: This case-control study covered 54 gastric cancer patients compared to 100 cancer free subjects as controls. Extraction of DNA was performed on bioptic samples and genotypes were identified with a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: The frequencies of MnSOD Ala/Ala, Ala/Val and Val/Val genotypes in healthy individuals were 24.3, 66.7 and 9%, respectively. However, in gastric cancer patients, Ala/Ala, Ala/Val and Val/Val were observed in 24.0, 48.0 and 28.0% (p=0.01). In patients the frequency of MnSOD Val allele was higher (52%) compared to that in controls (42%). Conclusions: The results of this study show a positive association between MnSOD Val-9Ala gene polymorphism and risk of gastric cancer disease in Iranian population.

Oxygen-atom Transfer of Bis(pyrroridinedithiocarbamato)dioxomolybdenum (Ⅵ) with Triphenylphosphine in 1,2-Dichloroethane (1,2-디클로로에탄에서 트리페닐포스핀과 비스(피로리딘디티오카바마토) 디옥소몰리브덴 (Ⅵ) 착물의 산소이동 반응)

  • Kim, Chang Su;Song, Se Jun
    • Journal of the Korean Chemical Society
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    • v.34 no.2
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    • pp.171-178
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    • 1990
  • The rates of the reaction Of $[MoO_2(S_2CNC_4H_8)_2]$ with triphenylphosphine in 1,2-dichloroethane have been by the spectrophotometric method. The increase in absorbance at 514 nm has been interpreted as a result of production of $[Mo_2O_3(S_2CNC_4H_8)_4]$ and the decrease in absorbance then corresponds to the reduction of $[Mo_2O_3(S_2CNC_4H_8)_4]$. The data suggest mechanisms involving the formation of $\mu$-oxo dimer in the first stage and molybdenum(IV) in the second stage.

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Synthesis and Solution Properties of La(III)-N-ethylmorpholine Complex

  • Anwar, Zeinab M.;Sung, Yong-Kiel
    • Bulletin of the Korean Chemical Society
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    • v.26 no.4
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    • pp.614-618
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    • 2005
  • The complex of the composition LaL(N$O_3)_3\;(H_2O)_2$ is prepared by the reaction of La($NO_3)_3{\cdot}6H_2O$ with Nethylmorpholine in aqueous medium. The ligand is involved in the complex as a neutral species where the chelation occurs via the oxygen of the ligand moiety and the nitrate groups as bidentate ligand. The chemical structure of the studied complex is confirmed through IR, XRD, and thermal analysis data. The complexation equilibria of La(III) with N-ethylmopholine is studied in aqueous medium at ionic strength I = 0.1 mol${\cdot}dm^{-3}\;KNO_3$ and at 25, 35 and 45 ${^{\circ}C}$, respectively. The thermodynamic parameters $\Delta$G, $\Delta$H and $\Delta$S values were calculated to prove the association with the complex formation. It is clearly observed that the process is accompanied by absorption of heat, i.e. endothermic process, while the entropy does not change greatly attributed to the release of constant number of water molecules during chelate formation.

Photodegradation of Gaseous Toluene Using Short-Wavelength UV/TiO2 and Treatment of Decomposition Products by Wet Scrubber (단파장자외선/TiO2 공정에 의한 가스상 톨루엔의 분해 및 습식세정장치에 의한 분해생성물의 제거)

  • Jeong, Ju-Young;Jurng, Jong-Soo
    • Journal of Environmental Science International
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    • v.16 no.4
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    • pp.433-440
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    • 2007
  • The photodegradation and by-products of the gaseous toluene with $TiO_2$ (P25) and short-wavelength UV ($UV_{254+185nm}$) radiation were studied. The toluene was decomposed and mineralized efficiently owed to the synergistic effect of photochemical oxidation in the gas phase and photocatalytic oxidation on the $TiO_2$ surface. The toluene by the $UV_{254+185nm}$ photoirradiated $TiO_2$ were mainly mineralized $CO_2$ and CO, but some water-soluble organic intermediates were also formed under severe reaction conditions. The ozone and secondary organic aerosol were produced as undesirable by-products. It was found that wet scrubber was useful as post-treatment to remove water-soluble organic intermediates. Excess ozone could be easily removed by means of a $MnO_2$ ozone-decomposition catalyst. It was also observed that the $MnO_2$ catalyst could decompose organic compounds by using oxygen reactive species formed in process of ozone decomposition.

Photocurrent Properties of TiO2 Nanorods Grown on FTO by Hydrothermal Method

  • Kim, Hyun;Yang, Bee Lyong
    • Journal of the Korean Ceramic Society
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    • v.52 no.6
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    • pp.531-534
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    • 2015
  • In this work, we undertake a comparative study of the crystallographic microstructures and photo-catalytic properties of rutile $TiO_2$ nanorods grown on FTO facing up and down by a hydrothermal method. An analysis of the fine structures showed that $TiO_2$ nanorods grown on FTO facing up were mixed with sea urchin and microsphere. These structures induced a vertical orientation of the nanorods on FTO. The saturated photocurrent densities of the $TiO_2$ nanorods grown both up and down were $1.5mA/cm^2$ in the former case, the IPCE was increased to 10% at 300~350 nm. The onset potential (${\fallingdotseq}$ flat band potential) of the nanorods grown on FTO facing up is negatively shifted to a value of -0.31 V. This is caused by an increase in the surface state, in this case the number of oxygen vacancies, and by the formation of $Ti^{3+}$. Therefore, the FTO facing direction is considered as a critical factor during the hydrothermal reaction for $TiO_2$ growth so as to develop an efficient photo-catalytic system.

Development of Petroleum-Based Carbon Composite Materials Containing Graphite/silicon Particles and Their Application to Lithium Ion Battery Anodes

  • Noh, Soon-Young;Kim, Young-Hoon;Lee, Chul-Wee;Yoon, Song-Hun
    • Journal of Electrochemical Science and Technology
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    • v.2 no.2
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    • pp.116-123
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    • 2011
  • Herein, a novel preparation method of highly homogeneous carbon-silicon composite materials was presented. In contrast to conventional solvent evaporation method, a milled silicon-graphite or its oxidized material were directly reacted with petroleum-derived pitch precursor. After thermal reaction under high pressure, pitch-graphite-silicon composite was prepared. Carbon-graphite-silicon composite were prepared by an air-oxidization and following carbonization. From energy dispersive spectroscopy, it was observed that small Si particles were highly embedded within carbon, which was confirmed by disappearance of Si peaks in Raman spectra. Furthermore, X-ray diffraction and Raman spectra revealed that carbon crystallinity decreased when the strongly oxidized silicon-graphite was added, which was probably due to oxygen-induced cross-linking. From the anode application in lithium ion batteries, carbon-graphite-silicon composite anode displayed a high capacity ($565\;mAh\;g^{-1}$), a good initial efficiency (68%) and an good cyclability (88% retention at 50 cycles), which were attributed to the high dispersion of Si particles within cabon. In case of the strongly oxidized silicongraphite addtion, a decrease of reversible capacity was observed due to its low crystallinity.