Visfatin Stimulates Proliferation of MCF-7 Human Breast Cancer Cells

김재근,Eun Ok Kim,Bo Ra Jeong,Young Joo Min,박정우,Eun Sook Kim,Il Seong Namgoong,Young Il Kim,Byung Ju Lee 한국분자세포생물학회 2010 Molecules and cells Vol.30 No.4

Obesity, a condition characterized by increased fat content and altered secretion of adipokines, is a risk factor for postmenopausal breast cancer. Visfatin has recently been established as a novel adipokine that is highly enriched in visceral fat. Here we report that visfatin regulated prolifera-tion of MCF-7 human breast cancer cells. Exogenous ad-ministration of recombinant visfatin increased cell prolif-eration and DNA synthesis rate in MCF-7 cells. Further-more, visfatin activated G1-S phase cell cycle progression by upregulation of cyclin D1 and cdk2 expression. Visfatin also increased the expression of matrix metallopro-teinases 2, matrix metalloproteinases 9, and vascular en-dothelial growth factor genes, suggesting that it may func-tion in metastasis and angiogenesis of breast cancer. Taken together, these findings suggest that visfatin plays an important role in breast cancer progression.

미생물 담체 성능 향상을 위한 금속 치환

김재근,민지은,박재우,Kim. Jae-Keun,Min. Jee-Eun,Park. Jae-Woo 한국방재학회 2008 한국방재학회 학술발표대회논문집 Vol.2008 No.1

To see the effect of magnesium on adhesion to natural zeolites, a series of batch tests were performed in this research. Mixed bacteria were sampled from the digestion tank at a local sewage treatment plant in Seoul. Magnesium-zeolites were synthesized by mixing natural zeolites with 0.096 M, 0.24 M, and 0.48 M of MgCl2 solution. For comparison, manganese and trivalent ferric zeolites were also prepared. Two grams of 0.2 mm <TEX>$\sim$</TEX> 0.3 mm sized zeolites(non-treated, Mg, Mn and Fe(III) treated zeolites) and 20 mL of water were mixed in a Corex 25 mL tube. Five milliliters of culture solution including bacteria was added to the tube. The tubes were equilibrated in a shaking incubator at mesophilic temperature <TEX>$(30{\pm}2^{\circ}C)$</TEX>. The bacterial concentrations were measured with a Microluminometer (New Horizons 3550i) and total organic carbon (TOC) spectrophotometer (Multi NC-3100).

Alkaline 및 Heavy Duty 건전지의 방전특성 비교

김재근,여태환 ( Jae Kun Kim,Tae Whan Yeu ) 한국화학공학회 1994 추계학술발표논문집 Vol.- No.-

중세의 선박에 대하여 (中世의 船舶에 대하여) -동서양선의 구조적 특성을 중심으로- (東西洋船의 構造的 特性을 中心으로)

김재근,Kim, Jae-Geun 국립문화재연구원 1981 헤리티지:역사와 과학 Vol.14 No.-

제올라이트를 이용한 생물막 형성시 미생물의 부착에 금속이 미치는 영향에 관한 연구

김재근,박인선,박재우,Kim, Jae Keun,Park, In Sun,Park, Jae-Woo 대한토목학회 2009 대한토목학회논문집 B Vol.29 No.3B

천연 제올라이트는 효과적인 다공성 구조와 높은 양이온 교환능력을 가지고 있을 뿐 만 아니라 비교적 저렴한 가격으로 인하여 흡착제 및 생물막 담체 등으로 널리 사용되는 물질이다. 본 연구에서는 천연 제올라이트를 이용한 생물막 형성시 제올라이트에 흡착된 금속 양이온$(Na^+,\;Ca^{2+},\;Mg^{2+},\;Al^{3+})$이 미생물의 흡착량에 어떠한 영향을 미치는지에 대하여 검토하였다. 본 실험을 위하여 천연 제올라이트의 양이온 교환능력(cation exchange capacity; CEC)의 10%, 20%, 100%를 금속 양이온으로 치환하여 개질시킨 Metal-modified zeolite(MMZ)를 사용하였고 미생물은 Pseudomonas putida를 계대배양하여 사용하였다. 미생물 흡착실험 결과 MMZ로의 미생물의 흡착량이 천연 제올라이트로의 흡착량 보다 일반적으로 증가하는 경향을 나타내었다. 즉, 10% CEC의 경우 미생물의 흡착량은 $Mg^{2+}>natural>Na^+>Al^{3+}>Ca^{2+}$, 20% CEC의 경우 $Mg^{2+}>Ca^{2+}>Al^{3+}>natural>Na^+$, 100%의 CEC의 경우 $Ca^{2+}>Mg^{2+}>natural>Al^{3+}>Na^+$의 흡착량을 나타내었다. 특히, 마그네슘으로 개질된 Mg-modified zeolite(Mg-MZ)의 경우 가장 높은 미생물 흡착량을 보였으며 10% CEC로 개질한 경우 천연 제올라이트보다 60% 이상 증가된 흡착량을 나타내었다. 그러나 제올라이트에 흡착된 양이온의 양이 증가할수록 미생물의 흡착량은 감소되는 경향을 나타내었는데, 즉, 10% CEC Mg-MZ의 경우 미생물의 흡착 증가량이 60% 이상이었으나 20% CEC의 경우 50%, 100% CEC의 경우 10%로 흡착 증가량이 감소되었다. 또한 제올라이트에 흡착된 $Mg^{2+}$와 수용액 상에 존재하는 $Mg^{2+}$가 미생물의 흡착량에 미치는 영향을 비교한 결과 제올라이트에 흡착될 수 있는 미생물의 최대흡착량은 큰 차이가 없는 것으로 조사되었다. Natural zeolite is widely used as sorbents and bio-media materials because it is cheap as well as it has efficient porous structures and large cation exchange. In this study, the effect of metal cations $(Na^+,\;Ca^{2+},\;Mg^{2+},\;Al^{3+})$ adsorbed to natural zeolite on the microorganism attachment was investigated. Metal-modified zeolites (MMZ) were prepared with 0.01 M, 0.02 M and 0.1 M NaCl, $CaCl_2$, $MgCl_2$ and $AlCl_3$ solutions respectively, which concentrations were equivalent to 10%, 20% and 100% of cation exchange capacity (CEC) of natural zeolite. Pseudomonas putida was used as microorganism which was cultivated in Beef Extract Medium at $26^{\circ}C$. The microorganism attachment to MMZ was increased more than natural zeolite. The amount of bacterial adhesion to MMZ and natural zeolite were $Mg^{2+}>natural>Na^+>Al^{3+}>Ca^{2+}$ under 10% of CEC, $Mg^{2+}>Ca^{2+}>Al^{3+}>natural>Na^+$ under 20% of CEC and $Ca^{2+}>Mg^{2+}>natural>Al^{3+}>Na^+$ under 100% of CEC. Especially, Mg-modified zeolite (Mg-MZ) showed the highest amount of bacterial adhesion, which increased the microorganism attachment 60% higher than natural zeolite under 10% of CEC. However, the amount of bacterial adhesion was decreased as the concentration of metal cations modified to zeolite were increased, showing that the increased amounts were 60% under 10% of CEC, 50% under 20% of CEC and 10% under 100% of CEC in Mg-MZ. Additionally, the effect of $Mg^{2+}$ in solution on the bacterial adhesion was investigated in order to compare it with the effect of $Mg^{2+}$ adsorbed to zeolite. The maximum quantity of bacterial adhesion to Mg-MZ was not different from the amount of microorganism attachment to the natural zeolite when $Mg^{2+}$ solution was added.

동기식 전송기술의 현황과 전망

김재근,이성경,Kim, Jae-Geun,Lee, Seong-Gyeong 한국전자통신연구원 1992 전자통신 Vol.14 No.2

본 고에서는 향후 전송망의 기반을 이룰 SDH(Synchronous Digital Hierarchy) 기본 동기식 다중기술의 원리, 특징 등을 살펴보고, 이의 국내.외적인 연구개발 동향을 조사하여 기술한다. 또한 향후 SDH전송과 관련하는 국제적인 표준화, 기술개발 방향, 그리고 망구축 방향 등을 예측하여 제시한다.

고분자물질(高分子物質) 첨가(添加)에 따른 마찰저항감소(摩擦抵抗減少)에 관한 연구(硏究)

김재근,차경옥,최형진,김종보,Kim, J.G.,Cha, K.O.,Choi, H.J.,Kim, C.B. 대한설비공학회 1996 설비공학 논문집 Vol.8 No.2

It is well known that drag reduction in single phase liquid flow is affected by polymer material, molecular weight, polymer concentration, pipe diameter, and flow velocity. Drag reduction in two phase flow can be applied to the transport of crude oil, phase change system such as chemical reactor, pool and boiling flow, and to present cavitation which occurs in pump impellers. But the research of drag reduction in two phase flow is not sufficient. The purpose of the present work is to evaluate the drag reduction by measuring pressure drop, void fraction, mean liquid velocity, and turbulent intensity whether polymer is added in the horizontal two phase system or not. Experiment has been conducted in a test section with the inner diameter of 24mm and the length of 1,500mm. The polymer materials used are two kinds of polyacrylamide[PAAM] and co-polymer[A611P]. The polymer concentration was varied with 50, 100 and 200 ppm under the same experimental conditions. Experimental results showed that the drag reduction of co-polymer is higher than that of polyacrylamide. Mean liquid velocities increased as polymer was added, and turbulent intensity decreased inversely near the pipe wall.

분무 열분해 CVD법으로 이동 중인 LaAlO_3(100) 단결정 위에 증착시킨 YBCO 박막의 특성

김재근,홍석관,김호진,유석구,조한우,안지현,주진호,이희균,홍계원,Kim, Jae-Gun,Hong, Suk-Kwan,Kim, Ho-Jin,Yu, Seok-Koo,Cho, Han-Woo,Ahn, Jin-Hyun,Joo, Jin-Hoo,Lee, Hee-Gyoun,Hong, Gye-Won 한국초전도학회 2006 Progress in superconductivity Vol.8 No.1

YBCO films were deposited on a moving substrate by a spray pyrolysis method using nitrate aqueous solution as precursors. Deposition was made on $LaAlO_3$(100) single crystal substrate by spraying precursor droplets generated by a concentric nozzle. The cation ratio of precursor solution was Y:Ba:Cu=1:2.65:4.5. The distance between nozzle and substrate was 15 cm. Substrate was transported with a speed ranging from 0.23 cm/min to 0.5 cm/min. Films were deposited at the pressure ranging from 10 Torr to 20 Torr and the deposition temperature was ranged from $740^{\circ}C\;to\;790^{\circ}C$. Oxygen partial pressure was controlled between 1 Tow and S Torr. Superconducting YBCO films were obtained from $740^{\circ}C\;to\;790^{\circ}C$ with an oxygen partial pressure of 3 Torr. Scanning electron microscope(SEM) and X-ray diffraction(XRD) observation revealed that films are smooth and highly texture with(001) plans parallel to substrate plane. Highest Jc was 0.72 $MA/cm^2$ at 77K and self-field for the film with a thickness of 0.15 m prepared at a substrate temperature of $740^{\circ}C$ and $PO_2$=3 Torr.

분사열분해 CVD 법으로 증착된 YBCO 박막의 특성에 미치는 기판 온도의 영향

김재근,홍석관,유석구,조한우,김병주,안지현,홍계원,이희균,Kim, Jae-Geun,Hong, Suk-Kwan,Yu, Seok-Koo,Cho, Han-Woo,Kim, Byung-Joo,Ahn, Ji-Hyun,Hong, Gye-Won,Lee, Hee-Gyoun 한국초전도학회 2007 Progress in superconductivity Vol.9 No.1

YBCO films have been synthesized using a spray pyrolysis method. We used nitrates of Y, Ba, Cu as precursors. Deposition was made on $LaAlO_3$ (100) single crystal substrate by spraying the mist of aqueous precursor solution generated by a concentric nozzle. The distance between concentric nozzle and substrate was 15 cm. C-axis oriented films were obtained at deposition temperature of $740{\sim}800^{\circ}C$ and working pressure of 20 Torr. Oxygen partial pressure was 3 Torr and substrate was transported with the speed ranging from 0.23 cm/min to 0.7 cm/min by reel to reel. Scanning electron microscope (SEM) and X-ray diffraction (XRD) observation revealed that films are smooth and highly textured with (001) planes parallel to substrate. Highest critical current density (Jc) was $1.38\;MA/cm^2$ at 77K and self-field for the film with a thickness of $0.5\;{\mu}m$ prepared at a substrate temperature of $780^{\circ}C$ and $PO_2\;=3\;Torr$. The effect of temperature on the microstructure and YBCO phase formation will be discussed.

SDH 전송과 ATM 기본 B-ISDN

김재근,Kim, Jae-Geun 한국전자통신연구원 1992 전자통신 Vol.14 No.2

본고에서는 광대역 multi-media 서비스를 제공하는 ATM(Asynchrous Transfer Mode) 기본 B-ISDN 전송망의 실현에 바탕을 두고, ATM 프로토콜 및 전달망의 구조 측면에서 ATM 신호경로의 설정과 이의 OAM(Operations, Administration and Maintenance) 방법,SDH(Synchronous Digital Hierachy) 기본 ATM 전송로의 구성, 그리고 관련 전송망 요소들에 대해 제시한다. 또한 기존 PDH(Plesiochronous Digital Hierarchy) 기본망으로부터 SDH-ATM 망으로, 그리고 기존 서비스 전용망으로부터 B-ISDN 으로의 진화전략을 전송망 측면에서 고찰한다.