• Title/Summary/Keyword: TCGF

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Brazilin Inhibits Mitogen Inducedd Cell Proliferation Despite of Augmentation of T Cell Growth Factor (TCGF) Production and Expression of IL-2 Receptors

  • Moon, Chang-Kiu;Mock, Myung-Soo;Yang, Kyung-Mee;Lim, Cheol-Hong;Kim, Kang-Seok;Chung, Jin-Ho;Moon, Chang-Hyun
    • Archives of Pharmacal Research
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    • v.15 no.4
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    • pp.275-282
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    • 1992
  • The present work was designed to investigate the effects of barzilin on ConAinducedd TCGF release, responsiveness to standardd IL-2, and mitogens-induced proliferation of splenocyte when administered intraperitoneally to 8 week-old C57BL/6 mice for 2 consecutive days. Immunological tests were performed 72 hours after the treatment of brailin. The administration of 50 mg/kg brazilin caused a noticeable increase in TCGF release and responsiveness to standard II-2 but inhibited mitogens-induced proliferation of splenocyte. These results that brazilin is able to modular immunological functions despite of its inhibitory effect on mitogen induced cell proliferation.

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Immunomodulating Activities of Brazilin in vitro

  • Moon, Chang-Kiu;Mock, Myung-Soo;Yang, Kyung-Mee;Han, Hye-Seung;Won, Hyeon-Soon;Kim, Ji-Young;Chung, Jin-Ho;Moon, Chang-Hyun
    • Archives of Pharmacal Research
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    • v.15 no.4
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    • pp.283-288
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    • 1992
  • This work was performed to investigate the effects of brazilin in vitro on mitrogen-induced proliferation, ConA-induced TCGF release and responsiveness to recombinant-induced proliferation, ConA-induced TCGF release and responsiveness to recombinant IL-2 using splenocytes from C57BL/6 female mice. Brazilin (29-80 ng/ml) caused a noticeable increase in TCGF production of splenocytes, but did not affect responsivness to recombinant IL-2, the expression of ConA-induced high affinity IL-2 receptor and mitogen-induced proliferation of splenocytes.

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BRAZILIN MODULATES THE IMMUNE FUNCTIONS IN NORMAL CBA FEMALE MICE

  • Moon, Chang-Kiu;Mock, Myung-Soo;Chung, Jin-Ho;Ha, Bae-Kin
    • Toxicological Research
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    • v.8 no.1
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    • pp.1-7
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    • 1992
  • Brazilin, the main constitutent of Caesalpinia sappan, was examined for its immunomodulating activities in normal CBA mice. Mitogen induced proliferation and production of ConA induced T-cell growth factors (TCGF) of splenocytes were significantly reduced in brazilin treated group, cmpared to control group. It was also found that suppressor activities of splenocytes in brazilin treated group was significantly increased compared to those in normal control group.

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Multiple Linear Regression Model for Prediction of Summer Tropical Cyclone Genesis Frequency over the Western North Pacific (북서태평양 태풍발생빈도 예측을 위한 다중회귀모델 개발)

  • Choi, Ki-Seon;Cha, Yu-Mi;Chang, Ki-Ho;Lee, Jong-Ho
    • Journal of the Korean earth science society
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    • v.34 no.4
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    • pp.336-344
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    • 2013
  • This study has developed a multiple linear regression model (MLRM) for the seasonal prediction of the summer tropical cyclone genesis frequency (TCGF) over the western North Pacific (WNP) using the four teleconnection patterns. These patterns are representative of the Siberian high Oscillation (SHO) in the East Asian continent, the North Pacific Oscillation (NPO) in the North Pacific, Antarctic oscillation (AAO) near Australia, and the circulation in the equatorial central Pacific during the boreal spring (April-May). This statistical model is verified by analyzing the differences hindcasted for the high and low TCGF years. The high TCGF years are characterized by the following anomalous features: four anomalous teleconnection patterns such as anticyclonic circulation (positive SHO phase) in the East Asian continent, pressure pattern like north-high and south-low in the North Pacific, and cyclonic circulation (positive AAO phase) near Australia, and cyclonic circulation in the Nino3.4 region were strengthened during the period from boreal spring to boreal summer. Thus, anomalous trade winds in the tropical western Pacific (TWP) were weakened by anomalous cyclonic circulations that located in the subtropical western Pacific (SWP) in both hemispheres. Consequently, this spatial distribution of anomalous pressure pattern suppressed convection in the TWP, strengthened convection in the SWP instead.

Fabrication of polycrystalline 3C-SiC micro pressure sensors for hightemperature applications (초고온용 다결정 3C-SiC 마이크로 압력센서의 제작)

  • Chung, Gwiy-Sang
    • Journal of Sensor Science and Technology
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    • v.19 no.1
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    • pp.31-35
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    • 2010
  • High temperature micro pressure sensors were fabricated by using polycrystalline 3C-SiC piezoresistors grown on oxidized SOI substrates by APCVD. These have been made by bulk micromachining under $1{\times}1mm^2$ diaphragm and Si membrane thickness of $20{\mu}m$. The pressure sensitivity of implemented pressure sensors was 0.1 mV/$V{\cdot}bar$. The nonlinearity and the hysteresis of sensors were ${\pm}0.44%{\cdot}FS$ and $0.61%{\cdot}FS$. In the temperature range of $25^{\circ}C{\sim}400^{\circ}C$ with 5 bar FS, TCS (temperature coefficient of sensitivity), TCR (temperature coefficient of resistance), and TCGF (temperature coefficient of gauge factor) of the sensor were -1867 ppm/$^{\circ}C$, -792 ppm/$^{\circ}C$, and -1042 ppm/$^{\circ}C$, respectively.

Characteristics of polycrystalline 3C-SiC micro pressure sensors for high temperature applications (초고온용 다결정 3C-SiC 마이크로 압력센서의 특성)

  • Thien, Duong Xuan;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.387-388
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    • 2008
  • High temperature micro pressure sensors were fabricated by polycrystalline (poly) 3C-SiC piezoresistors formed by oxidized SOI substrates with APCVD. These have been designed by bulk micromachining below $1{\times}1mm^2$ diaphragm and Si membrane $20{\mu}m$ thick. The pressure sensitivity of fabricated pressure sensor was 0.1 mV/Vbar. The non-linearity of sensor was ${\pm}0.44%$ FS and the hysteresis was 0.61% FS.TCS of pressure sensor was -1867 ppm/$^{\circ}C$, its TCR was -792 ppm/$^{\circ}C$, and TCGF to 5 bar was -1042 ppm/$^{\circ}C$ from 25 to $400^{\circ}C$.

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Interdecadal Variation of Tropical Cyclone Genesis Frequency over the Western North Pacific (북서태평양에서 열대 저기압 발생빈도의 십년간 변동 특성)

  • Choi, Ki-Seon;Kim, Baek-Jo;Lee, Seong-Lo;Park, Jong-Kil
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.6
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    • pp.31-39
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    • 2009
  • This study has found that there is a reverse phase with interdecadal variation in temporal variations of tropical cyclone (TC) genesis frequency (TCGF) between Northwest sector and Southeast sector, based on climatological mean tropical cyclone genesis location over the western North Pacific. The TCGF in the Northwest sector has been increased since the mid 1980s (1986-2005), while TCGF in the Southeast sector was higher until the early 1970s (1951-1970). The analysis of a difference between 1986-2005 and 1951-1970 showed results as follows: i) Through the analysis of vertical wind shear (VWS) and sea surface temperature (SST), less VWS and higher SST in the former (latter) period was located in the Northwest (Southeast) sector. ii) In the analysis of TC passage frequency (TCPF), TCs occurred in the Northwest sector frequently passed from east sea of the Philippines, through East China Sea, to Korea and Japan in the latter period, while TCs in the former period frequently has a lot of influences on South China Sea (SCS). In the case of TCs occurred in the Southeast sector, TCs in the west (east), based on $150^{\circ}E$ had a high passage frequency in the latter (former) period. In particular, TCs during the latter period frequently moved toward from the east sea of the Philippines to SCS and southern China. iii) This difference of TCPF between the two periods was characterized by 500 hPa anomalous pressure pattern. Particularly, anomalous cyclonic circulation strengthened over the East Asian continent caused anomalous southerlies along the East Asian coast line from the east sea of the Philippines to be predominate. These anomalous winds served as steering flows that TC can easily move toward same regions.

Mutant Frequency at the hprt Locus in Human T-Cell Exposed to Pentachlorophenol (Pentachlorophenol의 노출에 의한 사람 T-임파구의 hprt 유전자에서 돌연변이 빈도)

  • 윤병수;조명행;김인규;박선영;이영순
    • Toxicological Research
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    • v.13 no.1_2
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    • pp.71-78
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    • 1997
  • The mutational effects of pentachlorophenol (PCP) on the hypoxanthine phosphoribosyl transf erase (hprt) locus in human T-cell were analysed by T-cell clonal assay in vitro. Cells were exposed for 24 hours at primary culture to 0~100 ppm (W/V) PCP in dimethyl sulfoxide. Treated cells were allowed at the same time to stimulate by phytohemagglutinin (PHA) and T-cell growth factor (TCGF) and then seeded in medium containing 6-thioguanine to select for hprt-negative routants. We have also defined the optimal condition for the determination of mutant frequency. The parameters investigated include survival counting, first and second subculture for clonal efficiency plating and mutant plating. Under the optimal conditions, mutant frequencies of high dose-treated cells were significantly higher than those of non-treated or low dose cells. The results indicated a clear dose-effect relationship and showed that mutant frequency in 50 ppm PCP treated cell was 4.31$\times$$10^{-5}$ (background, 8.32$\times$$10^{-6}$). Above data strongly suggest that hprt mutation assay can be used as a biomarker for the environmental risk assessment.

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