• Title/Summary/Keyword: pae

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Suppression of Thrombospondin-1 Expression by PMA in the Porcine Aortic Endothelial Cells (정상 돼지 대동맥 내피세포에서 PMA에 의한 thrombospondin-1 발현 억제)

  • Chang, Seo-Yoon;Kang, Jung-Hoon;Hong, Kyong-Ja
    • Journal of Life Science
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    • v.14 no.1
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    • pp.154-162
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    • 2004
  • Thrombospondin-1 (TSP-1), a negative regulator in tumor growth and angiogenesis, is cell-type specifically regulated and at transcriptional level by external stimuli. Previously, we found that phorbol 12-myristate 13-acetate (PMA) suppressed TSP-1 expression in porcine aortic endothelial (PAE) cell, but enhanced in hepatoma cell line, Hep 3B cell. A region between -767 and -723 on the tsp-1 promoter was defined as a responsive site to the suppression in PAE cell. eased on the previous results, the molecular mechanism of TSP-1 expression was determined by characterizing interactions between cis-elements and trans-factors using three overlapped oligonucleotide probes, oligo a-1 (from -767 to -738), a-2 (-759 to -730) and a-3 (-752 to -723). The results from electromobility shift assay showed that PMA-induced suppression of TSP-1 transcription in PAE cell might be caused via a negative regulator binding to the region from -752 to -730 and additionally generated by lacking two positive regulators binding to the sites from -767 to -760 and from -752 to -730. Especially, PMA enhanced the binding ability of the negative regulator to the site from -752 to -730 in PAE cell, but anti-c-Jun did not affected its binding ability.

Effects of Ethylacetate Fraction of Plantago asiatica L. on Hypercholesterolemia Induced by High Cholesterol Diet in Rats (질경이(Plantago asiatica L.) 에틸아세테이트분획이 흰쥐의 고콜레스테롤혈증에 미치는 효과)

  • Lee Jae-Joon;Lee Jeong-Hwa;Jeong Chang-Ju;Choi Hyun-Sook;Lee Myung-Yul
    • Food Science and Preservation
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    • v.12 no.6
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    • pp.624-630
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    • 2005
  • Plantain was extracted with ethanol and fractionated systemically with n-hexane, chloroform, ethylacetate, n-butanol and water to study inhibitory effect on cholesterol synthesis in vitro. To screen the effect, inhibitory activities on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase obtained from Saccharomyces cerevisiae were examined using the five fractions of Plantain. The HMG-CoA reductase activity was inhibited most by ehylacetate fraction among the fractions, although the all five fractions had the effect To see the hypocholesterolemic effect of the ethylacetate fraction of Plantanin (PAE) in vivo, male Sprague-Dawley rats were received 5 types of diets for 6 weeks: normal diet group (NOR), high cholesterol diet group($1\%$ cholesterol and $0.25\%$ sodium cholate, CON), normal diet and PAE 70 mg/kg administered group(S1), high cholesterol diet and PAE 140 mg/kg administrated group(S2), and high cholesterol diet and PAE 140 mg/kg administered group(S3). Body weight gains of the CON were significantly increased compared to those of S1, S2 and S3. Activities of serum AST and ALT were tended to be increased in CON compared with NOR and reduced by the PAE administration. Concentrations of serum total cholesterol, free cholesterol, LDL-cholesterol, triglyceride and the atherogenic index were tended to be decreased in the PAE administered groups compared with the CON. HDL-cholesterol and phospholipid concentrations were significantly decreased in the CON and markedly increased by the PAE administered groups. Taten together, it is suggested that the ethylacetate fraction of Plantanin exerts antiatherosclerotic effect by reducing serum cholesterol concentrations in rats fed high cholesterol diets.

A Study on Linearity and Efficiency Improvement for 3-Way Doherty Amplifier (3-Way Doherty 증폭기의 선형성 및 효율 개선에 관한 연구)

  • Hong, Yong-Eui;Yang, Seung-In
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2005.11a
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    • pp.77-78
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    • 2005
  • In this paper, Compact Microstrip Resonants Cell(CMRC) have been employed to suppress IMD(Intermodulation Distortion) of the 3-Way Doherty amplifier. This method can not only improve the linearly and the efficiency but also is simpler, smaller and more inexpensive than existing linearly methods; (for example Harmonic feedback, Back off, Feed-forward, Predistortion and so on.) Also, the proposed 3-way Doherty amplifier using only one divider has been reduced size of existing 3-Way Doherty amplifier. As a result, the proposed Doherty amplifier using CMRC and only one divider has been improved for the IMD$_3$ by 4.474dBc, and the PAE by 9.199%, respectively.

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Ku-Band Power Amplifier MMIC Chipset with On-Chip Active Gate Bias Circuit

  • Noh, Youn-Sub;Chang, Dong-Pil;Yom, In-Bok
    • ETRI Journal
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    • v.31 no.3
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    • pp.247-253
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    • 2009
  • We propose a Ku-band driver and high-power amplifier monolithic microwave integrated circuits (MMICs) employing a compensating gate bias circuit using a commercial 0.5 ${\mu}m$ GaAs pHEMT technology. The integrated gate bias circuit provides compensation for the threshold voltage and temperature variations as well as independence of the supply voltage variations. A fabricated two-stage Ku-band driver amplifier MMIC exhibits a typical output power of 30.5 dBm and power-added efficiency (PAE) of 37% over a 13.5 GHz to 15.0 GHz frequency band, while a fabricated three-stage Ku-band high-power amplifier MMIC exhibits a maximum saturated output power of 39.25 dBm (8.4 W) and PAE of 22.7% at 14.5 GHz.

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