아침 식사시간의 다른 사람들에서 혈장 그렐린의 변화

이상엽,김윤진,김형회,손한철,전태용,심문섭 대한비만학회 2002 The Korean journal of obesity Vol.11 No.2

연구배경 : 최근 식욕조절인자로 관심이 집중되고 있는 그렐린(ghrelin)은 식사 전후로 독한 일중변동을 보인다. 하지만, 지금까지는 실험적으로 일정한 열량의 표준 음식을 일정한 식사시간에 공급한 이후 그렐린의 농도 변화를 관찰하였다. 저자 등은 평소 아침 식사시간이 각기 다른 사람들에서 아침 식사 전후의 혈장 그렐린 농도 변화를 관찰하여 향후 외래 환경에서도 그렐린 관련 연구가 가능하도록 기초 자료를 제공하고자 하였다. 방법 : 연구에 대한 설명을 듣고 동의한 23.4 ~ 35.5세 사이의 비교적 건강한 동양인 남자 4명을 대상으로 하였다. 신체 계측을 한 후 이중 에너지 방사선 측정법 (Lunar prodigy, GE medical systems, Waukesha, Wisconsis, USA, 이하 DEXA)으로 체지방을 측정하였다. 연구 대상자 모두 평소 아침 식사시간이 일정하였지만 연구 시작 2주전부터 아침 식사시간을 엄격히 고정하도록 하였다. 스트레스가 없는 상태에서 아침 식사를 하지 않는 지원자는 오전 6시 30분부터, 나머지는 아침식사 시간 1시간 전부터 1시간 간격으로 점심 식사 전인 오전 11시 30분까지 채혈하였다. 각각의 검체로 부터 혈장 그렐린은 상업적인 방사선면역측정법 (Phoenix Pharmaceuticals, Inc., Belmont, CA)으로 측정되었다. 랩틴은 Ⅰ-125 표지 랩틴을 이용한 이중항체 방사선면역측정법으로, 혈장 인슐린은 항체 부착관을 이용한 방사선면역측정법으로, 혈당은 포도당산화 효소법에 의해 Synchron LX 20 (Beckman Coulter, Inc, Fullerton, USA)으로 측정하였다. 결과 : 연구 대상자의 체질량지수는 22.9 ~ 27.1 kg/㎡이었고, 허리둘레는 80.3 ~ 93.3 cm이었다. DEXA로 측정한 결과 전체 체지방과 체부지방 비율은 각각 27.1 ~ 31.8%와 32.7 ~ 32.4%이었다. 아침 식사를 하지 않는 자를 제외한 나머지 연구 대상자의 아침 식사 직전의 식후 2시간의 혈장 그렐린 농도는 각각 113.0 ~ 800.0 pg/mL, 78.3 ~ 553.0 pg/mL이었고 랩틴 농도는 각각 4.9 ~ 5.1 ng/mL, 4.4 ~ 4.7 ng/mL 이었다. 혈장 그렐린 랩틴 농도는 아침 식사 직전에 비해 식사 2시간 후 각각 7.2 ~ 30.9%와 7.8 ~ 10.2%감소되었다. 아침식사를 하지 않는 대상자의 경우 인슐린과 혈당치가 변화가 없음에도 불구하고 혈장 그렐린 농도는 오전 7시 30분에 가장 낮았다. 그 외 연구 대상자에서는 각기 다른 시간이더라도 아침 식사 2시간 후의 혈장 그렐린 농도가 가장 낮았다. 결론 : 평소 아침 식사시간이 다른 사람들에게서 혈장 그렐린 농도는 각기 다른 아침 식사 2 시간 후에 가장 낮았다. 아침 식사를 하지 않는 경우에는 혈장 그렐린 농도가 오전 7시 30분에 가장 낮았다. Background : Recently, the particular interest is on ghrelin, the dietary control factor among many scientists and it a toxic diurnal variations has been demonstrated before and after meal. However, the experimental approach has been only to see the changes in the concentration of ghrelin after intake of meals standardized with fixed calories at scheduled meal hours. the authors of this particular experiment have tried to observe and record the changes in concentrations of plasma ghrelin of persons with different breakfast hours. This might help in providing a basis for further possible studies in outpatient setting. Method : A group of four relatively healthy males whose ages between 23.4 and 35.5 with prior agreements were selected for this study. After body measurements, body lipid status was measured based on Lunar prodigy (GE medical systems, Waukesha, Wisconsin, USA) which is also referred to as DEXA. All of the selected persons had somewhat fixed breakfast time; however, they were asked to strictly keep their breakfast time fixed and steady starting two weeks before the beginning of experiment. The bloods of those who skip their breakfast without any particular stress were sampled at 6:30 AM, whereas the rest had different schedule, whose bloods were sampled every hour starting 1 hour before the first meal of the day till just before lunch (11:30 Am). From each blood sample, the level of plasma ghrelin was measured using the commercial radioimmune assay (Phoenix Pharmaceuticals, Inc., Belmont, CA). Leptin was measured with double antibody radioimmune assay using Ⅰ-125 labelled leptin, plasma insulin with radioimmune assay using antibody attachment tube, and blood sugar with Synchron LX20 (Beckman Coulter, Inc, Fullerton, USA) using glucosylation enzyme method. Result : The body mass index of the volunteers was 22.9 ~ 27.1 kg/㎡, with 80.3 ~ 93.3 cm waist circumference. Based on measurements by DEXA, the rates of total body lipid and trunk lipid were each 27.1 ~ 31.8% and 32.7 ~ 32.4%, respectively. The concentrations of plasma ghrelin of those who consume their breakfast before and 2 hour after their breakfast are 113.0 ~ 800.0 pg/mL and 78.3 ~ 553.0 pg/mL. The concentrations of leptin are 4.9 ~ 5.1 ng/mL and 4.4 ~ 4.7 ng/mL. Compared to the concentration of plasma ghrelin and of leptin recorded just before breakfast, it showed 7.2 ~ 30.9% and 7.8 ~ 10.2% decrease, respectively, 2 hours after breakfast. For those who skip their breakfast, the plasma concentration of ghrelin was recorded the lowest at 7:30 AM, even though there was no change in insulin and blood sugar. The rest of the subjects had their lowest plasma ghrelin concentration at 2 hours after breakfast, despite their different meal schedule. Conclusion : The persons with different breakfast hours had their lowest plasma concentration of ghrelin at 2 hours after breakfast. In contrast, the persons who skip their breakfast had their lowest concentration at 7: 30 AM.

Synthesis and characterization of dithienylbenzobis(thiadiazole)-based low band-gap polymers for organic electronics

Oh, Heong Sub,Kim, Tae-Dong,Koh, Yun-Hyuk,Lee, Kwang-Sup,Cho, Shinuk,Cartwright, Alex,Prasad, Paras N. Royal Society of Chemistry 2011 Chemical communications Vol.47 No.31

<P>New donor–acceptor alternating conjugated polymers were synthesized and characterized. Among them, PCPBBT exhibited a band-gap of 1.01 eV and ambipolar characteristics with <I>μ</I><SUB>h</SUB> = 7.1 × 10<SUP>−4</SUP> cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> and <I>μ</I><SUB>e</SUB> = 3.3 × 10<SUP>−3</SUP> cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>.</P> <P>Graphic Abstract</P><P>A series of low band-gap donor–acceptor alternating conjugated polymers based on the bisthiadiazole unit was synthesized and their optical and physical properties were investigated. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1cc11899d'> </P>

Effect of Surrogate Aggregates on the Thermal Conductivity of Concrete at Ambient and Elevated Temperatures

Yun, Tae Sup,Jeong, Yeon Jong,Youm, Kwang-Soo Scientific World, Inc 2014 The Scientific World Journal Vol.2014 No.-

<P> The accurate assessment of the thermal conductivity of concretes is an important part of building design in terms of thermal efficiency and thermal performance of materials at various temperatures. We present an experimental assessment of the thermal conductivity of five thermally insulated concrete specimens made using lightweight aggregates and glass bubbles in place of normal aggregates. Four different measurement methods are used to assess the reliability of the thermal data and to evaluate the effects of the various sensor types. The concrete specimens are also assessed at every 100°C during heating to ~800°C. Normal concrete is shown to have a thermal conductivity of ~2.25Wm<SUP>-1</SUP> K<SUP>-1</SUP>. The surrogate aggregates effectively reduce the conductivity to ~1.25Wm<SUP>-1</SUP> K<SUP>-1</SUP> at room temperature. The aggregate size is shown not to affect thermal conduction: fine and coarse aggregates each lead to similar results. Surface contact methods of assessment tend to underestimate thermal conductivity, presumably owing to high thermal resistance between the transducers and the specimens. Thermogravimetric analysis shows that the stages of mass loss of the cement paste correspond to the evolution of thermal conductivity upon heating. </P>

Synergistic Integration of Mesenchymal Stem Cells and Hydrostatic Pressure in the Expansion and Maintenance of Human Hematopoietic/Progenitor Cells

Kang, Yun Gyeong,Jeong, Jee-Yeong,Lee, Tae-Hee,Lee, Ho Sup,Shin, Jung-Woog Hindawi 2018 Stem cells international Vol.2018 No.-

<P>Ex vivo expansion of hematopoietic stem/progenitor cell (HSPC) has been investigated to improve the clinical outcome of HSPC transplantation. However, ex vivo expansion of HSPCs still faces a major obstacle in that HPSCs tend to differentiate when proliferating. Here, we cocultured HSPCs with mesenchymal stem cells (MSCs) and divided the HSPCs into two fractions according to whether they came into adherent to MSCs or not. Additionally, we used hydrostatic pressure (HP) to mimic the physical conditions <I>in vivo</I>. Even nonadherent cells expanded to yield a significantly larger number of total nucleated cells (TNCs), adherent cells maintained the HSPC phenotype (CD34<SUP>+</SUP>, CD34<SUP>+</SUP>CD38<SUP>−</SUP>, and CD133<SUP>+</SUP>CD38<SUP>−</SUP>) to a greater extent than nonadherent cells and had superior clonogenic potential. Moreover, applying HP significantly increased the number of TNCs, the frequency of the immature HSPC phenotype, and the clonogenic potential. Furthermore, the genetic markers for the HSPC niche were significantly increased under HP. Our data suggest that the nonadherent fraction is the predominant site of HSPC expansion, whereas the adherent fraction seems to mimic the HSPC niche for immature cells. Moreover, HP has a synergistic effect on expansion and functional maintenance. This first study utilizing HP has a potential of designing clinically applicable expansion systems.</P>

¹H, ¹⁵N and ¹³C Backbone Assignments and Secondary Structures of C-ter100 Domain of Vibrio Extracellular Metalloprotease Derived from Vibrio vulnificus

Yun, Ji-Hye,Kim, Hee-Youn,Park, Jung-Eun,Cheong, Hae-Kap,Cheong, Chae-Joon,Lee, Jung-Sup,Lee, Weon-Tae Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.10

Vibrio extracellular metalloprotease (vEP), secreted from Vibrio vulnificus, shows various proteolytic function such as prothrombin activation and fibrinolytic activities. Premature form of vEP has an N-terminal (nPP) and a C-terminal (C-ter100) region. The nPP and C-ter100 regions are autocleaved for the matured metalloprotease activity. It has been proposed that two regions play a key role in regulating enzymatic activity of vEP. Especially, C-ter100 has a regulatory function on proteolytic activity of vEP. C-ter100 domain has been cloned into the E. coli expression vectors, pET32a and pGEX 4T-1 with TEV protease cleavage site and purified using gel-filtration chromatography followed by affinity chromatography. To understand how C-ter100 modulates proteolytic activity of vEP, structural studies were performed by heteronuclar multi-dimensional NMR spectroscopy. Backbone $^1H$, $^{15}N$ and $^{13}C$ resonances were assigned by data from standard triple resonance and HCCH-TOCSY experiments. The secondary structures of vEP C-ter100 were determined by TALOS+ and CSI software based on hydrogen/deuterium exchange. NMR data show that C-ter100 of vEP forms a ${\beta}$-barrel structure consisting of eight ${\beta}$-strands.

가스하이드레이트 : 환경과 에너지

윤태섭(Tae-Sup Yun) 대한토목학회 2011 대한토목학회지 Vol.59 No.9

국제소식(ASCE 주요기사)

윤태섭(Tae Sup Yun) 대한토목학회 2018 대한토목학회지 Vol.66 No.5

Elongation and gravitropic responses of <i>Arabidopsis</i> roots are regulated by brassinolide and IAA

KIM, TAE-WUK,LEE, SUN MIN,JOO, SE-HWAN,YUN, HYE SUP,LEE, YEW,KAUFMAN, PETER B.,KIRAKOSYAN, ARA,KIM, SOO-HWAN,NAM, KYOUNG HEE,LEE, JUNE SEUNG,CHANG, SOO CHUL,KIM, SEONG-KI Blackwell Scientific Publications 2007 Plant, cell and environment Vol.30 No.6

<P>ABSTRACT</P><P>Exogenously applied brassinolide (BL) increased both gravitropic curvature and length of primary roots of <I>Arabidopsis</I> at low concentration (10<SUP>−10</SUP> M), whereas at higher concentration, BL further increased gravitropic curvature while it inhibited primary root growth. <I>BRI1-GFP</I> plants possessing a high steady-state expression level of a brassinosteroid (BR) receptor kinase rendered the plant's responses to gravity and root growth more sensitive, while BR-insensitive mutants, <I>bri1-301</I> and <I>bak1</I>, delayed root growth and reduced their response to the gravitropic stimulus. The stimulatory effect of BL on the root gravitropic curvature was also enhanced in auxin transport mutants, <I>aux1-7</I> and <I>pin2</I>, relative to wild-type plants, and increasing concentration of auxin attenuated BL-induced root sensitivity to gravity. Interestingly, IAA treatment to the roots of <I>bri1-301</I> and <I>bak1</I> plants or of plants pretreated with a BL biosynthetic inhibitor, brassinazole, increased their sensitivity to gravity, while these treatments for the BL-hypersensitive transgenic plants, <I>BRI1-GFP</I> and <I>35S-BAK1</I>, were less effective. Expression of a <I>CYP79B2</I> gene, encoding an IAA biosynthetic enzyme, was suppressed in BL-hypersensitive plant types and enhanced in BL-insensitive or -deficient plants. In conclusion, our results indicate that BL interacts negatively with IAA in the regulation of plant gravitropic response and root growth, and its regulation is achieved partly by modulating biosynthetic pathways of the counterpart hormone.</P>

백서의 간에서의 허혈-재관류 손상 후에 오는 아포프토시스

김태윤(Tae-Yun Kim),이원석(Won Seok Lee),윤익진(Ik-Jin Yun),박성규(Sung Kyu Park),홍대식(Dae Sik Hong),김연수(Yun Soo Kim),심찬섭(Chan Sup Shim),이민혁(Min-Hyuck Lee),김재준(Jae-Jun Kim) 한국간담췌외과학회 2000 한국간담췌외과학회지 Vol.4 No.2

A solution processible semiconducting polymer interlayer for blue light-emitting diodes

Kim, Yun Ho,Jung, Myung-Sup,Yoon, Dong Ki,Jee, Mu Guen,Jung, Hee-Tae IOP Pub 2007 Nanotechnology Vol.18 No.17

<P>Polyimide containing triphenylamine derivative (TPD-PI) was synthesized to prepare a polymer interlayer having insolubility in common nonpolar solvents for light-emitting polymers. The TPD-PI was prepared from the synthesized diamine monomer and 4,4′-(hexafluoropropylidene)-diphthalic anhydride by the standard two-step polymerization method, which involved ring-opening polymerization and subsequent cyclodehydration. We incorporated this novel semiconducting polymer (TPD-PI) between the hole conducting layer (PEDOT:PSS) and the blue-emitting layer (PFO, poly(dioctylfluorene)) of a light-emitting diode. The molecular architecture of the TPD-PI interlayer means that it is soluble in most aprotic polar solvents, and completely insoluble in acetone, toluene, and xylene, which are used as solvents for most emitting layers; these solubility properties make the direct spin-coating of the interlayer possible. The surfaces of interlayer have stability against the general organic solvents for a polymeric layer with a nanometre scale. The efficiency increases from 0.25 to 0.351 cd A<SUP>−1</SUP> and the lifetime rises by 50% as a result of the insertion of the interlayer, which also has advantages in the following areas: interface structure, solubility characteristics, energetic position, hole transport of the interlayer, and thermal stability of the polyimide main chain.</P>