Exendin-4 induction of cyclin D1 expression in INS-1 beta-cells: involvement of cAMP-responsive element.

Kim, M-J,Kang, J-H,Park, Y G,Ryu, G R,Ko, S H,Jeong, I-K,Koh, K-H,Rhie, D-J,Yoon, S H,Hahn, S J,Kim, M-S,Jo, Y-H Journal of Endocrinology, Ltd. [etc.] 2006 The Journal of endocrinology Vol.188 No.3

<P>Glucagon-like peptide-1 (GLP-1) and its analog exendin-4 (EX) have been considered as a growth factor implicated in pancreatic islet mass increase and beta-cell proliferation. This study aimed to investigate the effect of EX on cyclin D1 expression, a key regulator of the cell cycle, in the pancreatic beta-cell line INS-1. We demonstrated that EX significantly increased cyclin D1 mRNA and subsequently its protein levels. Although EX induced phosphorylation of Raf-1 and extracellular-signal-regulated kinase (ERK), both PD98059 and exogenous ERK1 had no effect on the cyclin D1 induction by EX. Instead, the cAMP-elevating agent forskolin induced cyclin D1 expression remarkably and this response was inhibited by pretreatment with H-89, a protein kinase A (PKA) inhibitor. Promoter analyses revealed that the cAMP-responsive element (CRE) site (at position -48; 5'-TAACGTCA-3') of cyclin D1 gene was required for both basal and EX-induced activation of the cyclin D1 promoter, which was confirmed by site-directed mutagenesis study. For EX to activate the cyclin D1 promoter effectively, CRE-binding protein (CREB) should be phosphorylated and bound to the putative CRE site, according to the results of electrophoretic mobility shift and chromatin immunoprecipitation assays. Lastly, a transfection assay employing constitutively active or dominant-negative CREB expression plasmids clearly demonstrated that CREB was largely involved in both basal and EX-induced cyclin D1 promoter activities. Taken together, EX-induced cyclin D1 expression is largely dependent on the cAMP/PKA signaling pathway, and EX increases the level of phosphorylated CREB and more potently trans-activates cyclin D1 gene through binding of the CREB to the putative CRE site, implicating a potential mechanism underlying beta-cell proliferation by EX.</P>

비냉각 적외선 열상장비용 CMOS Readout IC 설계

한석룡,윤동한,강대석,박재우,송성해,신경욱,우회구,윤태준,이상돈 金烏工科大學校 1998 論文集 Vol.19 No.-

A CMOS readout circuit for uncooled infrared Focal Plane Array (FPA) deteftor is presented, which is a key component in InfraRed (IR) imaging systems. The designed readout circuit satisfies various design requirements and constraints such as impedance matching, low noise, large dynamic range, low power dissipation and small pitch size. For impedance matching between the detector and preamplifier, a new circuit based on MOS diode structure with variable substrate biasing is devised. Also, tunable low pass filter with single-pole is used to suppress high frequency noise. In addition, a clamp circuit is used to enhance the signal-pole is used to suppress high frequency noise. In addition, a clamp circuit is used to enhance the signal-to-noise ratio of the readout output signals. A prototype 64×64 ROIC is designed using 0.65-㎛ 2P3M (double poly, tripple metal) N-Well CMOS process. It contains 62,000 devices including transistors, capacitors and resistors on an area of about 6.3×6.7㎟.

The AC Loss Measurement of the KSTAR PF1 Coils During the First Commissioning

Lee, H J,Oh, D K,Chu, Y,Park, Y M,Park, H T,Choi, J H,Hahn, S H,Park, K R,Oh, Y K,Yang, H L IEEE 2010 IEEE transactions on applied superconductivity Vol.20 No.3

<P>The AC loss in a large superconducting magnet coil shows a tendency to be changed after assembly. For the ac loss measurement of the Korea Superconducting Tokamak Advanced Research (KSTAR) superconducting coils after assembly, several current scenarios, trapezoidal pulses and a DC offset sinusoidal pulses, were applied to the PF1 Upper (U) and Lower (L) coils during the commissioning. The measurement was done once before and once after the plasma discharge experiments. All coil data were obtained by the tokamak monitoring system and helium distribution system which were designed to measure temperature, pressure, and mass-flow at both inlets and outlets of the coils. The PF1 coils of the cable-in-conduit conductor type were made of Nb<SUB>3</SUB>Sn superconducting strands, whose winding scheme is 20 layers with each layer having 9 turns. Each has 10 cooling channels for the heat removal by the supercritical helium at 4.5 K. For the trapezoidal pulse tests, the current was increased up to 4 kA with several different ramp rates and a 2 kA DC offset and 0.5 kA sine waves with different frequencies from 0.1 Hz to 0.3 Hz were applied to the coil. According to the analyses, the AC loss was slightly decreased for the same condition after 700 plasma shots. It was believe that such a result was due to reduced inter-strand resistances which changed the transverse resistance between the inter-strands. The coupling time constant was estimated to be 32 ms in the trapezoidal tests and 13.6 ms for the DC offset sinusoidal pulses. The former is larger than the latter because of the effect of the jacket eddy current loss due to Incoloy 908 which is a ferromagnetic material. Considering the jacket eddy current losses, the coupling time constant was recalculated and the value estimated to be about 13 ms for all current wave forms during first commissioning.</P>

Search for the H Dibaryon in (K-, K+) Reactions

Bahk,S. Y.,Chung,K. S,Chung,S. H.,Funahashi,H.,Hahn,C. H.,Hara,T.,Hirata,S.,Hoshino,K.,Ieiri,M.,Iijima,T.,Imai,K.,Ishigami,T.,Itow,Y.,Kazuno,M.,Kikuchi,K.,Kim,C. O.,Kim,D. C.,Kim,J. Y.,Kobayashi,M.,Ko 國立昌原大學校 基礎科學硏究所 1992 基礎科學硏究所論文集 Vol.3 No.-

We have studied(??) reactions from an emulsion target. The S--2H dibaryon has been searched for by the analysis of the ??? momentum spectrum together with emulsion data. No evidence of H production was observed in the mass range of 1.90-2.16 GeV/c². Upper limits for the production cross section of the H are (0.2-0.6)% of that for the quasifree ??? production at the 90% confidence level.

A Single-Flux-Quantum Shift Register based on High-$T_c$ Superconducting Step-edge Josephson Junctions

Sung G.Y.,Choi, C.H.,Suh J.D.,Han, S. K.,Kang, K.Y.,Hwang, J.S.,Yoon, S.G.,Jung, K.R.,Lee, Y.H.,Kang, J.H.,Kim, Y.H.,Hahn, T.S. The Korean Superconductivity Society 1999 Progress in superconductivity Vol.1 No.1

We have fabricated and tested a simple circuit of the rapid single-flux-quantum(RSFQ) four-stage shift register using a single layer high-$T_c$ superconducting (HTS) $YBa_2Cu_3O_{7-x}$ (YBCO) thin film structure with 9 step-edge Josephson junctions. The circuit includes two read superconducting quantum interference devices(SQUID) and four stages. To establish a robust HTS RSFQ device fabrication process, we have focussed on the reproducible process of sharp and straight step-edge formation as well as the ratio of film thickness to step height, t/h. The spread of step-edge junction parameters was measured from each 13 junctions with t/h=1/3, 1/2, and 2/3 at various temperatures. We have demonstrated the simplified operation of the shift register at 65 K.

Canaliculo-Rhinostomy : Modified Arruga's Procedure

韓德基 大韓眼科學會 1968 大韓眼科學會雜誌 Vol.9 No.2-3

Stargardt's Macular Dystrophy

한덕기 영남대학교의과대학 1998 Yeungnam University Journal of Medicine Vol.15 No.2

황백색의 반점이나 주근깨에 의래 둘러싸인 색소망병증의 특징을 가지고 있는 Stargardt's macular dystrophy는 가족력을 가지며 진행성의 시력감소를 나타내는 질환이다. 이 질환의 초기에는 육안으로 관찰되지 않는 병변이 있을 수 있으며 이 경우 형광안저촬영검사를 시행하여 병변의 특징을 관찰하여야 한다. 저자가 비교적 최근에 경험한 6례의 경우들은 다양한 발병시기를 가졌으며 양안시력이 20/100이하로 감소하였으며 4례에서 안전위도검사에서 비정상소견을 나타내었다. 형광안저촬영검사에서 특징적 과형광부 및 저형광부를 나타내었으며 경과관찰에 따라 다양한 정도의 진행양상을 나타내었다. 따라서 저자는 Stargardt's macular dystrophy가 의심되는 환자의 경우 진단적 검사를 시행함과 동시에 가족에 대한 검사를 시행하여 이 질환의 분포를 파악하고 밝혀진 환자에 대하여서는 장기적으로 경과관찰을 하며 시력의 정도에 EK라 저시력 보조기 등을 이용한 재활을 적극적으로 하여야 할 것으로 생각한다.

Meibom 腺癌

權達萬,陸康友,韓德基 大韓眼科學會 1970 大韓眼科學會雜誌 Vol.11 No.2-3

Tropane Spirohydantoin들의 합성 및 구조분석

정대일,이도훈,송주현,이용균,최순규,박유미,한정태 동아대학교 환경문제연구소 2006 硏究報告 Vol.28 No.1

The tropane ring system is an important substructure in a number of natural products and synthetic compounds of biological and medicinal importance. As a result of the significance of the tropane ring system, the purpose of this study is the synthesis of anticonvulsant compounds of new s tructure anticipated anticonvulsant activity. After we first synthesized the various N-substituted nortropinone derivatives, we prepared new nortropane alkaloids and nortropinone derivatives. Substantially, we tried several experiments to optimize reaction condition. The tropane spirohydantoins 17, 18, 19, 20, 21 were respectively synthesized by the treatment of corresponding N-substituted nortropinone with potassium cyanide and ammonium carbonate.

C-2와 C-2,4 위치에 치환된 8-aza-bicyclo[3.2.1]octan-3-one 유도체 합성 및 구조분석

정대일,이도훈,송주현,이용균,최순규,박유미,한정태 동아대학교 환경문제연구소 2006 硏究報告 Vol.28 No.1

The tropane ring system is an important substructure in a number of natural products and synthetic compounds of biological and medicinal importance. As a result of the significance of the tropane ring system, the purpose of this study is the synthesis of anticonvulsant compounds of new structure anticipated anticonvulsant activity. After we first synthesized the various N- substituted 8-aza-bicyclo[3.2.1]octan-3-one derivatives. We prepared now 2-substituted nortropinones. 2-Substituted 8-aza- bicyclo [3.2.1]octan-3-ones were obtained from diluted NaOH concentration(0.01N NaOH) in similar method of synthesis of 2,4-disubstituted 8-aza-bicyclo[3.2.1]octan-3-ones 23, 24, 25 were respectively synthesized by the reaction of corresponding N-substituted 8-aza-bicyclo[3.2.1]octan-3-one with corresponding aldehyde in presence of 5N-NaOH solution in ethanol and dichloromethane at room temperature. Substantially, we tried several experiments to optimize reaction condition. Continuously, the synthesis and anticonvulsant activity evaluation of a new class of 8-aza-bicyclo[3.2.1]octan-3-one derivatives are in progress and will be reported in future.