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Silencing MR-1 attenuates atherosclerosis in ApoE-/- mice induced by angiotensin II through FAK-Akt -mTOR-NF-kappaB signaling pathway

  • Chen, Yixi;Cao, Jianping;Zhao, Qihui;Luo, Haiyong;Wang, Yiguang;Dai, Wenjian
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.2
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    • pp.127-134
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    • 2018
  • Myofibrillogenesis regulator-1 (MR-1) is a novel protein involved in cellular proliferation, migration, inflammatory reaction and signal transduction. However, little information is available on the relationship between MR-1 expression and the progression of atherosclerosis. Here we report atheroprotective effects of silencing MR-1 in a model of Ang II-accelerated atherosclerosis, characterized by suppression focal adhesion kinase (FAK) and nuclear factor kappaB ($NF-{\kappa}B$) signaling pathway, and atherosclerotic lesion macrophage content. In this model, administration of the siRNA-MR-1 substantially attenuated Ang II-accelerated atherosclerosis with stabilization of atherosclerotic plaques and inhibited FAK, Akt, mammalian target of rapamycin (mTOR) and NF-kB activation, which was associated with suppression of inflammatory factor and atherogenic gene expression in the artery. In vitro studies demonstrated similar changes in Ang II-treated vascular smooth muscle cells (VSMCs) and macrophages: siRNA-MR-1 inhibited the expression levels of proinflammatory factor. These studies uncover crucial proinflammatory mechanisms of Ang II and highlight actions of silencing MR-1 to inhibit Ang II signaling, which is atheroprotective.

A Study for Fast Handoff Improvement Performance on Using MAC layer Information at Wireless LAN (무선 랜에서 MAC 계층의 정보를 이용한 고속 핸드오프 성능 향상에 관한 연구)

  • Kim Dong-Ok;Gang Dong-Jin;Im Jeong-Hui;Song Yeong-A
    • 한국정보통신설비학회:학술대회논문집
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    • 2004.08a
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    • pp.27-30
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    • 2004
  • 본 논문에서는 무선 랜 환경에서 단말을 사용하는 사용자의 이동으로 인한 서비스영역의 변화에도 끊김 없는 서비스를 제공하기 위한 방식을 제안한다 제안방식은 이동하는 단말이 사용 가능한 채널탐색과정 중 MAC주소를 참조하여 단말의 이동을 알려주는 방식을 사용한다. 기존방식과 제안방식에 대해서 시뮬레이션을 통한 성능분석을 수행하였다. 단말의 이동을 채널탐색과정에서 인식함으로 단말에게 전송되어야 하는 데이터를 버퍼링 한 후 재결합과정이 발생하면 즉시, 전송하는 방식으로 구성되므로 핸드오프 기간 동안에 Throughput 감소가 적게 이루어짐을 확인하였다.

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Influence of Preparation Conditions on the Formation of Copper (II) Architectures with Pyrazine-2,3,5-tricarboxylic Acid

  • Wang, Feng-Qin;Lin, Shu;Guo, Ming-Lin;Xu, Jun-Jian;Wang, Xiao-Qing;Zhao, Yong-Nan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2351-2357
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    • 2011
  • Three new metal-organic copper(II) complexes, $[Cu(H_2PZTC)_2]_n{\cdot}2nH_2O$ (1), $[Cu(HPZTC){\cdot}2H_2O]_n{\cdot}2nH_2O$ (2), and $Cu_2[(PZHD)(OH)(H_2O)_2]_n$ (3) ($H_3PZTC$ = pyrazine-2,3,5-tricarboxylic acid, $PZHD^{3-}$ = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from $Cu(II)/H_3PZTC$ system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, $H_3PZTC$ ligands loose one and two protons, which were transformed into $H_2PZTC^-$ anion and $HPZTC^{2-}$ dianion under different preparation condition, respectively. Furthermore, two ligands coordinate with Cu(II) cations in different modes, leading to the formation of the different chain structures. In complex 3, $H_3PZTC$ ligand was converted into a new ligand-PZHD by in situ decarboxylation and hydroxylation under a higher pH value than that for complexes 1 and 2. PZHD ligands link the Cu(II) cations to form a 2D layer structure. These results demonstrate that the preparation conditions, including pH value and reaction temperature etc, play an important role in the construction of complexes based on $H_3PZTC$ ligand.

Icaritin Preparation from Icariin by a Special Epimedium Flavonoid-Glycosidase from Aspergillus sp.y848 Strain

  • Wang, Zhenghao;Liu, Chunying;Yu, Hongshan;Wu, Bo;Huai, Baoyu;Zhuang, Ziyu;Sun, Changkai;Xu, Longquan;Jin, Fengxie
    • Journal of Microbiology and Biotechnology
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    • v.32 no.4
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    • pp.437-446
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    • 2022
  • In this study, to obtain icaritin with high pharmacological activities from icariin, which has a content ratio of over 58% in the total flavonoids of Epimedium herb, a special Epimedium flavonoid-glycosidase was produced, purified and characterized from Aspergillus sp.y848 strain. The optimal enzyme production was gained in a medium containing 5% (w/v) wheat bran extract and 0.7% (w/v) Epimedium leaf powder as the enzyme inducer, and strain culture at 30℃ for 6-7 days. The molecular weight of the enzyme was approximately 73.2 kDa; the optimal pH and temperature were 5.0 and 40℃. The enzyme Km and Vmax values for icariin were 15.63 mM and 55.56 mM/h. Moreover, the enzyme hydrolyzed the 7-O-glucosides of icariin into icariside II, and finally hydrolyzed 3-Orhamnoside of icariside II into icaritin. The enzyme also hydrolyzed 7-O-glucosides of epimedin B to sagittatoside B, and then further hydrolyzed terminal 3-O-xyloside of sagittatoside B to icarisiede II, before finally hydrolyzing 3-O-rhamnoside of icarisiede II into icaritin. The enzyme only hydrolyzed 7-O-glucoside of epimedin A or epimedin C into sagittatoside A or sagittatoside C. It is possible to prepare icaritin from the high-content icariin in Epimedium herb using this enzyme. When 2.5% icariin was reacted at 40℃ for 18-20 h by the low-cost crude enzyme, 5.04 g icaritin with 98% purity was obtained from 10 g icariin. Also, the icaritin molar yield was 92.5%. Our results showed icaritin was successfully produced via cost-effective and relatively simple methods from icariin by crude enzyme. Our results should be very useful for the development of medicines from Epimedium herb.

Dynamic changes of multi-notoginseng stem-leaf ginsenosides in reaction with ginsenosidase type-I

  • Xiao, Yongkun;Liu, Chunying;Im, Wan-Teak;Chen, Shuang;Zuo, Kangze;Yu, Hongshan;Song, Jianguo;Xu, Longquan;Yi, Tea-Hoo;Jin, Fengxie
    • Journal of Ginseng Research
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    • v.43 no.2
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    • pp.186-195
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    • 2019
  • Background: Notoginseng stem-leaf (NGL) ginsenosides have not been well used. To improve their utilization, the biotransformation of NGL ginsenosides was studied using ginsenosidase type-I from Aspergillus niger g.848. Methods: NGL ginsenosides were reacted with a crude enzyme in the RAT-5D bioreactor, and the dynamic changes of multi-ginsenosides of NGL were recognized by HPLC. The reaction products were separated using a silica gel column and identified by HPLC and NMR. Results: All the NGL ginsenosides are protopanaxadiol-type ginsenosides; the main ginsenoside contents are 27.1% Rb3, 15.7% C-Mx1, 13.8% Rc, 11.1% Fc, 7.10% Fa, 6.44% C-Mc, 5.08% Rb2, and 4.31% Rb1. In the reaction of NGL ginsenosides with crude enzyme, the main reaction of Rb3 and C-Mx1 occurred through Rb3${\rightarrow}$C-Mx1${\rightarrow}$C-Mx; when reacted for 1 h, Rb3 decreased from 27.1% to 9.82 %, C-Mx1 increased from 15.5% to 32.3%, C-Mx was produced to 6.46%, finally into C-Mx and a small amount of C-K. When reacted for 1.5 h, all the Rb1, Rd, and Gyp17 were completely reacted, and the reaction intermediate F2 was produced to 8.25%, finally into C-K. The main reaction of Rc (13.8%) occurred through Rc${\rightarrow}$C-Mc1${\rightarrow}$C-Mc${\rightarrow}$C-K. The enzyme barely hydrolyzed the terminal xyloside on 3-O- or 20-O-sugar-moiety of the substrate; therefore, 9.43 g C-Mx, 6.85 g C-K, 4.50 g R7, and 4.71 g Fc (hardly separating from the substrate) were obtained from 50 g NGL ginsenosides by the crude enzyme reaction. Conclusion: Four monomer ginsenosides were successfully produced and separated from NGL ginsenosides by the enzyme reaction.

A study on the Inclination measurement with tilt sensor on the tower crane (기울기 센서를 이용한 타워크레인의 기울어짐 측정방안에 관한 연구)

  • Kang, Shin-Hyuk;Kong, Jung-Shik;Kwon, Oh-Sang;Jang, Mun-Suk;Shin, Woon-Chul;Lee, Dong-Kwang;Jang, Chol-Woong;Chung, Ki-Ho;Yeom, Moon-Jin;Lee, Eung-Hyuk
    • Proceedings of the KIEE Conference
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    • 2007.10a
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    • pp.91-92
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    • 2007
  • 산업현장에서 사용되는 타워크레인의 전도 상황을 측정하기 위한 시스템은 현재 풍속계에 의존하고 있는데, 풍속계의 경우 타워크레인의 기울어짐을 정략적으로 측정할 수 없는 센서이기 때문에 정확한 상황 판단이 어렵고, 운전자나 관리자의 판단이 필요한 문제를 갖는다. 그래서 보다 정확한 정도를 측정하기 위해 타워크레인의 지브(jib) 휘어짐과 타워축의 휘어짐을 측정하여 정량적인 위험 상황을 경보 할 수 있는 전도 측정 장치가 필요하기 때문에 타워크레인의 좌/우 및 상/하 기울어짐에 대한 정량적인 측정이 가능한 기울기 센서를 이용한 센서 시스템을 구축하고, 타워크레인의 동작 위험성을 알리기 위한 경보 기법을 구축 했다.

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Instrument of building outer wall window cleaning robot and controller layout that use vacuum adsorption technology (진공흡착 기술을 사용한 건물외벽 유리창 청소 로봇의 구현)

  • Lee, Dong-Kwang;Kim, Myung-Jong;Kwon, Soon-Won;Choi, Mun-Sik;Im, Young-Hoon;Kong, Jung-Shik;Jang, Mun-Suk;Kwon, Oh-Sang;Lee, Eung-Hyuk
    • Proceedings of the KIEE Conference
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    • 2007.10a
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    • pp.259-260
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    • 2007
  • 본 논문은 건물 외면의 유리창 청소로봇에 관한 것으로, 더욱 세부적으로는 청소 시스템을 갖춘 로봇을 사람이 닦기 힘들거나 위험한 고층건물이나 아파트 둥의 실외 유리창에 흡착시켜 청소로봇을 이용하여 실외 유리창을 자동으로 닦을 수 있게 하는 건물 외면의 유리창 청소로봇에 관한 것이다. 진공펌프를 사용하여 유리창에 안정적으로 흡착할 수 있도록 하였고, 블루투스를 이용하여 무선 조종이 가능하도록 하여 사용자가 원거리에서 로봇의 청소를 제어할 수 있도록 하였다.

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