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Role of p53-dependent PI3K in Radioresistance of Colon Cancer Cells (대장암 세포의 방사선저항성에 대한 p53의존성 PI3K의 역할)

  • Lee, Heui-Kwan;Kim, Jong-Suk;Kwon, Hyoung-Cheol
    • Journal of Food Hygiene and Safety
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    • v.25 no.3
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    • pp.258-262
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    • 2010
  • Radiotherapy is one of the major therapies for cancer treatment. p53 acts as a central mediator of the cellular response to stressful stimuli, such as radiation. Recently it has been known that activation of the phosphatidylinositol-3-kinase (PI3K) pathway is associated with radioresistance. In this study, we investigated whether X-irradiation up-regulates PI3K in a p53-dependent manner in human colon cancer cells. In order to study this phenomenon, we have treated p53-wild type and p53-mutant type HCT116 cells with X-ray. Treatment of wild type HCT116 cells with 8 Gy resulted in a marked increase in PI3K (p85), which paralleled an increase in PTEN, a counterpart of PI3K. However, these effects of X-rays in the p53-mutant cells were not observed. These results suggest that the X-irradiation-induced up-regulation of PI3K/PTEN pathway is p53-dependent.

Preparation and Characterization of Doped $Fe_2O_3$ and GaAs Photosemiconductive Electrodes for $CO_2$ Fixation

  • Kim, Il Kwang;Lee, Seong Jae;Kim, Min Su;Jeong, Seung Il;Park, Byung Sun;Kim, Youn Geun
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.669-674
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    • 1995
  • The preparation and characterization of photosemiconductive electrodes of GaAs and of $Fe_2O_3$ doped with MgO or CaO were investigated. The doped $Fe_2O_3$ photosemiconductive electrodes were prepared from thin films sintered at temperatures from 1,100 to $1,450^{\circ}C$, and rapidly quenched in distilled water. The surfaces of the electrodes containing both corundum structure of $Fe_2O_3$ and spinel structure of $Mg_xFe_{3-x}O_4$ or $Ca_xFe_{3-x}O_4$ were analyzed by X-ray diffraction and scanning electron microscopy. The cathodic and anodic photocurrents on these electrodes indicated a critical doping amount of 5-11 wt. %. The photocurrents were enhanced when GaAs electrodes were treated with methylene violet the anodic photo-currents were temporarial enhanced and changed to the cathodic ptotocurrents after the surface was dryed.

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Human RPS4X/Y Genes and Pseudogene Family: Chromosomal Localization and Phylogenetic Analysis

  • Lee, Ji-Won;Yi, Joo-Mi;Shin, Kyung-Mi;Kim, Heui-Soo
    • Journal of Life Science
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    • v.11 no.2
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    • pp.81-82
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    • 2001
  • The human ribosomal protein 54 genes, RPS4X and RPS4Y are located on the X and Y chromosomes. They have been postulated as candidate for Turner syndrome which was characterized by gonadal dysgenesis, short stature, and various external and internal anomalies. Using the BLAST search program, we identified sixteen RPS4 pseudogenes from the human genome and analyzed them phylogenetically. The RPS4-C12-1, C12-2, and C12-3 pseudogenes from chromosome 12 have been evolved independently during hominid evolution. The RPS4X gene from X chromosome it closely related to the RPS4-C12-2 from chromosome 12 and RPS4-C5 from chromosome 5, whereas the RPS4Y gene is very closely related to RPS4-C16 from chromosome 16. The exact mapping of the RPS4 pseudogene family was peformed, indicating that the RPS4 pseudogene family was mapped on human chromosomes 1, 2, 5, 6, 8, 10, 11, 12, 13, 16, 18, 19 and 20. Taken together, the precise chromosomal localization and phylegenetic relationship of the RPS4 pseudo-genes could be of great use in further study for understanding the Turner syndrome.

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Microflora and Color of Soybean Paste Sterilized by Counterflow Hat Exchanger (향류식 열교환기에 의하여 멸균된 된장의 미생물군 및 색도)

  • 유승곤;김인호;김종생;최성현;오만진;김용국;이인기
    • KSBB Journal
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    • v.13 no.6
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    • pp.724-729
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    • 1998
  • To develop a large scale countercurrent single pass heat exchanger for continuous transportation and sterilization of soybean paste, microflora and color value of sterilized soybean paste were examined at various sterile condition. Aerobes, anaerobes, molds, yeasts and lactic acid bacteria were 5.1 x 107 CFU/g, 7.1 x 107 CFU/g, 2.6 x 105 CFU/g, 4.3 x 106 CFU/g, 1.3 x 107 CFU/g, respectively in raw soybean paste. In gold band ampoule test, aerobes and anaerobes of soybean paste were viable up to 90$^{\circ}C$, but become unviable at 100$^{\circ}C$. Molds decreased rapidly and yeasts decreased slowly from 70$^{\circ}C$. Lactic acid bacteria were unviable at 60$^{\circ}C$ within 10 min. In color test, Hunter L, a, and b values of soybean paste were 50.2, +5.6, and +17.8, respectively. After heating in polyethylene film bag at 80$^{\circ}C$, Hunter values were not so much changed and become 50.2, +4.7, and +19.7, respectively. The micorflora and color of soybean paste sterilized in a large scale heat exchanger system resulted in very similar to those of gold band ampoule and polyethylene film bag by effective heat transfer.

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Electrical Characteristics of $Bi_{3.25}Nd_{0.75}Ti_{3}O_{12}$ Thin Films Prepared by MOD Process Depending on Annealing Temperatures (MOD법을 이용 제조한 $Bi_{3.25}Nd_{0.75}Ti_{3}O_{12}$ 박막의 열처리 온도에 따른 전기적 특성)

  • Kim, Ki-Beom;Jang, Gun-Eik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.346-349
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    • 2002
  • Ferroelectric $Bi_{4-x}Nd_{x}Ti_{3}O_{12}(BNdT)$ thin films with the composition(x=0.75) were prepared on $Pt/Ti/SiO_{2}/Si(100)$ substrate by metal-organic deposition. The films were annealed by various temperatures from 550 to $650^{\circ}C$ and then the electrical and structural characteristics of BNdT films were investigated for the application of FRAM. Electrical properties such as dielectirc constant, 2Pr and capacitance were quite dependent on the thermal heat treatment. The measured 2Pr value on the BNdT capacitor annealed at $650^{\circ}C$ was $56{\mu}C/cm^{2}$ at an applied voltage of 5V. In fatigue characteristics value remained costant up to $8{\times}10^{10}$ read/write switching cycles at a frequency of 1Mhz regardless of annealing temperatures.

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Fabrication of Mo based Thermal Spray Composite Powder by Self- propagating High- temperature Synthesis (SHS 합성에 의한 몰리브덴계 용사용 복합분말의 제조)

  • Park, Je-Sin;Sim, Geon-Ju
    • Korean Journal of Materials Research
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    • v.11 no.9
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    • pp.763-768
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    • 2001
  • Molybdenum-based thermal spray powder is widely used for coating the moving parts of the internal combustion engines due to its excellent wear resistance. A composite powder of the $Mo_{40}(Al_{1-x}Si_x)_{60}$ system was synthesized using the SHS method. The synthesized bulk was pulverized and specially treated to produce thermal spray powder. It was found that the synthesis reaction consisted of two-steps: the formation of $Al_8/Mo_3$ and the formation of Mo(Al,Si)$_2$. Both the temperature and the rate of the SHS reaction linearly increased with the increase of the value of x in $Mo_{40}(Al_{1-x}Si_x)_{60}$, The temperature and the rate of the reaction were also affected by the compacting density of the specimens, exhibiting the maximum valves at 62% and 60%, respectively. Since spherical shape is advantageous to the thermal spraying process, shape-control of the powder was attempted with PVA as a binding additive, resulting in the successful production of almost perfectly spherical powder of 80 $\mu\textrm{m}$ Ø$(d_{50})$ mean particle size.

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Nanotube shape on the Ti-29Nb-xHf alloys with applied potentials

  • Park, Seon-Yeong;Choe, Han-Cheol
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.119-119
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    • 2016
  • Over the last years the anodic formation of ordered $TiO_2$ nanotube layers has created significant scientific interest. Titanium oxide nanotube formation on the titanium or titanium alloy surface is expected to be important to improve cell adhesion and proliferation under clinical conditions. It should be possible to control the nanotube size and morphology for biomedical implant use by controlling the applied voltage, alloying element, current density, anodization time, and electrolyte. $TiO_2$ nanotubes show excellent biocompatibility, and the open volume in the tubes may be exploited as a drug release platform and so on. Therefore, in this study, Nanotube shape on the Ti-29Nb-xHf alloys with applied potentials was reserched. $TiO_2$ nanotube formation on Ti-29Nb-xHf alloys was carried out using anodization technique as a function of applied DC potential (10 V to 30 V and 30 V to 10 V) and anodization time for 60~120 min in $1MH_3PO_4$ with small additions of (0.8 wt. %, to 1.2 wt. %) NaF. The morphology change of anodized Ti-29Nb-xHf alloys was determined by FE-SEM, XRD, and EDS.

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An investigation on the in si.tu measurement of the oil-concentration

  • Kim, Chang-Nyeun;Park, Young-Moo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.8 no.2
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    • pp.80-88
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    • 2000
  • In order to predict thermodynamic performance of refrigeration system, it is required to know the oil concentration of the refrigerant/oil mixture. The current method is to extract the working mixture and then to measure the oil weight. In this study, oil concentration is measured in si.tu way without any extraction of the working fluid. Based on the measurement, a working equation is presented as follows, C=a +b x t +c x $t^2$ +(d + e x t +f x $t^2$) x SG. C is oil concentration, t is temperature($^{\circ}C). SG Is specific gravity of mixture and a~f is coefficients The oil concentration ranges over 0~l2 wt% and the temperature ranges over 20~50$^{\circ}C. The specific gravity and temperature are measured using the on-line densimeter and thermometer. This working equation enables to predict the oil concentration without any extraction of the mixture. This equation can be applied for R-12/Naphthenic oil and R-134a/P0E oil liquid mixtures.

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Stress Distributions in a Plate due to Shear Loading Uniformly Distributed on the End Portions of its Side Boundary. (부분적(部分的)인 균일전단하중(均一傳達荷重)을 받는 평판(平板)에서의 응력분포(應力分布))

  • Hyo-Chul,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.7 no.1
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    • pp.37-44
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    • 1970
  • The plate under shear loading umformly distributed on the end portions of its side boundary was considered. Infinite hyperbolic serieses and Fourier serieses were combined as a stress function and from which exact solutions for the 15 cases for the parameters of b/L=0.25, 0.5, 1.0 and l/L=0.2, 0.4, 0.6, 0.8, 1.0 are obtained. In each cases the first 5 terms of the infinite series at the 36 points as shown in Fig. 3. The results are presented in Fig. 4-1, 4-2, and 4-3. The conclusions are as follows: 1) The stresses ${\sigma}_x$ increase very slightly as $\chi$ increases in the range of 0<x<L-l 2) When the parameters satisfy the conditions b/L<0.25 and l/L<0.2, the stresses in the region of 0<x<L-l can be obtained by replacing the uniform shear loading by the equivalent uniform shear loading by the equivalent uniform tensile force and pure bending moment at x=l. 3) The stress ${\sigma}_y$ is negligible throughout the region. 4) When the parameter b/L varies, the stresses ${\sigma}_x$ and u vary as L/b, while strain $\upsilon$ varies as $(L/b)^2$.

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A Clinical Case Report on the Malalignment Treated by Chuna Manual Therapy - Based on the Full Spine AP X-ray and VAS - (추나치료를 이용한 골반, 척추 및 견갑대 부정렬의 치험 3례 - Full spine AP X-ray, VAS 분석에 따른 -)

  • Park, Ji-Hyun;Jeong, Hyun-A;Hong, Seo-Young
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.5 no.2
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    • pp.135-149
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    • 2010
  • Objectives : This study was designed to observe the effect of Chuna manual therapy on the asymmetrical alignment. Methods : To analyze static structural alignment, posterior inferior ilium deviation(PI), inflare change of pelvis were checked from full spine AP X-ray. And Cobb's angle of spine and height of shoulder girdle were analyzed. To evaluate the pain visual analogue score(VAS) was scored. Chuna therapy treated 8-10 times for 1 month. Results and Conclusions : In 3 cases, VAS was improved significantly. Full spine AP X-ray shows improvement of structural imbalace. Shoulder height difference, cobb's angle, pelvic insufficiency improved considerably. These results suggest that Chuna therapy might be effective for malalignment patients.

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