S-1 plus irinotecan and oxaliplatin for the first-line treatment of patients with metastatic colorectal cancer: a prospective phase II study and pharmacogenetic analysis

Kim, S Y,S Hong, Y,K Shim, E,Kong, S-Y,Shin, A,Baek, J Y,Jung, K H Nature Publishing Group 2013 The British journal of cancer Vol.109 No.6

<P><B>Background:</B></P><P>S-1 is an oral fluoropyrimidine that mimics infusional 5-fluorouracil. The aim of this phase II trial was to explore the clinical efficacy of the triplet regimen TIROX, which consists of S-1, irinotecan and oxaliplatin.</P><P><B>Methods:</B></P><P>Forty-two chemo-naive patients with metastatic colorectal cancer (mCRC) were planned to be enrolled and be treated with irinotecan 150 mg m<SUP>−2</SUP> followed by oxaliplatin 85 mg m<SUP>−2</SUP> on day 1 and S-1 80 mg m<SUP>−2</SUP> per day from day 1 to 14 every 3 weeks. Polymorphisms in the <I>UGT1A1</I>, <I>UGT1A6</I>, <I>UGT1A7</I> and <I>CYP2A6</I> genes were analysed.</P><P><B>Results:</B></P><P>Between July 2007 and February 2008, 43 patients were enrolled. An objective response was noted in 29 patients (67.4%, 95% confidence interval: 53.4–81.4), of which 2 achieved durable complete responses. The median progression-free survival was 10.0 months and the median overall survival was 19.2 months. Significant grade 3 or 4 adverse events were neutropenia (45.2%), febrile neutropenia (9.5%), diarrhoea (7.1%) and vomiting (9.5%). Increased gastrointestinal toxicities were associated with the presence of <I>UGT1A6*2</I> or <I>UGT1A7*3</I> and an improved tumour response was noted in those without variant alleles of <I>CYP2A6</I> or <I>UGT1A1*60</I>.</P><P><B>Conclusion:</B></P><P>The combination of S-1, irinotecan and oxaliplatin showed favourable efficacy and tolerability in untreated patients with mCRC.</P>

HWE(Hot Wall Epitaxy)에 의한 CuGaSe₂/GaAs epilayer 성장과 광전기적 특성

홍광준,정준우,백형원,정경아,방진주,진윤미,김소형 조선대학교 기초과학연구소 2001 自然科學硏究 Vol.24 No.-

수평 전기로에서 CuGaSe₂ 다결정을 합성하여 HWE(Hot Wall Epitaxy) 방법으로 CuGaSe₂/GaAs epilayer를 반절연성 GaAs(100)기판 위에 성장하였다. CuGaSe₂/GaAs epilayer는 증발원의 온도를 610℃, 기판의 온도를 450℃로 하였다. CuGaSe₂/GaAs epilayer의 결정성의 조사에서 20K에서 광발광(photoluminescence) 스펙트럼이 672.6nm(1.8432eV)에서 엑시톤 방출 스펙트럼이 가장 강하게 나타났으며, 이중결정 X-선 요동곡선(DCRC)의 반폭치(FWHM)도 138 arcsec로 가장 작아 최적 성장 조건임을 알 수 있었다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293K에서 각각 4.87×10^(23) electron/m³, 1.29×10² m²/v-s 였다. CuGaSe₂/GaAs epilayer의 광전류 단파장대 봉우리들로부터 20K에서 측정된 ΔCr(Crystal field splitting)은 약 0.09 eV ΔSo(spin orbit coupling)는 0.2498 eV였다. 20K의 광발광 측정으로부터 고품질의 결정에서 볼 수 있는 자유 엑시톤 (free exciton)과 매우 강한 세기의 중성 받개(acceptor) 구속 엑시톤 (bound exciton)등의 피크가 관찰되었다. 이때 받개 구속 엑시톤 (bound exciton)의 반치폭과 결합에너지는 각각 8meV와 93.2meV 였다. 또한 Haynes rule에 의해 구한 불순물의 활성화 에너지는 466meV였다. The stochiometric mixture of evaporating materials for the CuGaSe₂/GaAs epilayer was prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal CuGaSe₂, it was found tetragonal structure whose lattice constant a_(0) and c_(0) were 5.615 Å and 11.025 Å, respectively. To obtain the CuGaSe₂/GaAs epilayer, CuGaSe₂ mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy(HWE) system. The source and substrate temperature were 610 ℃ and 450 ℃ respectively. The crystalline structure of CuGaSe₂/GaAs epilayer was investigated by the double crystal X-ray diffraction(DCXD). Hall effect on this sample was measured by the method of van der pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 150 K and by polar optical scattering in the temperature range 150 K to 293 K. From the photocurrent spectra by illumination of polarized light of the CuGaSe₂/GaAs epilaye. We have found that values of spin orbit coupling ΔSo and crystal field splitting ΔCr was 0.0900 eV and 0.2498 eV, respectively. From the photoluminescence measurement of CuGaSe₂/GaAs epilayer, we observed free excition(Ex) observable only in high quality crystal and neutral acceptor-bound exciton (A^(0); X) having very strong peak intensity. And, the full width at half maximum and binding energy of neutral donor bound excition were 8 meV and 93.2 meV, respectively. By Haynes rule, an activation energy of impurity was 466 meV.

Status of the KSTAR superconducting magnet system development

Kim, K.,Park, H.K.,Park, K.R.,Lim, B.S.,Lee, S.I.,Chu, Y.,Chung, W.H.,Oh, Y.K.,Baek, S.H.,Lee, S.J.,Yonekawa, H.,Kim, J.S.,Kim, C.S.,Choi, J.Y.,Chang, Y.B.,Park, S.H.,Kim, D.J.,Song, N.H.,Kim, K.P.,So International Atomic Energy Agency 2005 Nuclear fusion Vol.45 No.8

<P>The aim of the Korea superconducting tokamak advanced research (KSTAR) project is to develop a steady-state-capable advanced superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Since the KSTAR mission includes the achievement of a steady-state-capable operation, the use of superconducting coils is an obvious choice for the magnet system. The KSTAR superconducting magnet system consists of 16 toroidal field (TF) and 14 poloidal field (PF) coils which include 8 central solenoid coils. Both the TF and PF coil systems use internally-cooled cable-in-conduit conductors (CICC). The TF coil system provides a magnetic field of 3.5 T at the plasma centre and the PF coil system provide a flux swing of 17 V s. The major achievement in the KSTAR magnet system development includes the development of CICC, a full size TF model coil, a background magnetic field generation coil system and the construction of a large scale superconducting magnet and the CICC test facility. TF and PF coils are at the stage of fabrication for the KSTAR completion in the year 2007.</P>

Inconel 718 상향 엔드밀링시 절삭력에 미치는 공구형상오차

이영문,양승한,장승일,백승기,김선일 한국공작기계학회 2002 한국공작기계학회 춘계학술대회논문집 Vol.2002 No.-

In end milling process, the undeformed chip section area and cutting forces vary periodically with phase change of the tool. However, the real undeformed chip section area deviates from the geometrically ideal one owing to cutter runout and tool shape error. In this study, a method of estimating the real undeformed chip section area which reflects cutter runout and tool shape error was presented during up-end milling of Inconel 718 using measured cutting forces. The specific cutting resistance, K_(r) and K_(t) are defined as the radial and tangential cutting forces divided by the modified chip section area. Both of K_(r) and K_(t) values become smaller as the helix angle increases from 30° to 40°. Whereas they become larger as the helix angle increases from 40° to 50°. On the other hand, the K_(r) and K_(t) values show a tendency to decrease with increase of the modified chip section area and this tendency becomes distinct with smaller helix angle.

Effects of sevoflurane on collagen production and growth factor expression in rats with an excision wound

LEE, H.-J.,KWON, J.-Y.,SHIN, S.-W.,BAEK, S.-H.,CHOI, K.-U.,JEON, Y.-H.,KIM, W.-S.,BAE, J.-H.,CHOI, H.-J.,KIM, H.-K.,BAIK, S.-W. Blackwell Publishing Ltd 2010 Acta anaesthesiologica Scandinavica Vol.54 No.7

<P>Background</P><P>Sevoflurane is a widely used inhalation anesthetic, but there are no studies on its effect on the wound-healing process. This study was undertaken to evaluate the effect of exposure time to sevoflurane on wound healing.</P><P>Method</P><P>Male Sprague–Dawley rats were used. Two circular full-thickness skin defects 8 mm in diameter were made on the dorsum of the rats. The animals were divided into six groups according to exposed gas type and time: S1 (sevoflurane, 1 h), S4 (sevoflurane, 4 h), S8 (sevoflurane, 8 h), O1 (oxygen, 1 h), O4 (oxygen, 4 h), and O8 (oxygen, 8 h). The surface area of the wounds was measured 0, 1, 3, and 7 days after surgery. Separately, the mean blood pressures (MBP) and arterial oxygen pressures (PaO<SUB>2</SUB>) were monitored during the sevoflurane exposure. Collagen type I production and transforming growth factor-β1 (TGF-β1) and basic fibroblast growth factor (bFGF) expression on the wound surface were analyzed. Routine histological analysis was also performed.</P><P>Result</P><P>Exposure duration to sevoflurane had no influence on MBP and PaO<SUB>2</SUB>. The reduction in wound size and collagen type I production was delayed in S8. The expression of TGF-β1 and bFGF on the wound surface in S8 was significantly attenuated in S8. The histology of the S8 demonstrated a delayed healing status.</P><P>Conclusions</P><P>Prolonged exposure to sevoflurane might alter the inflammatory phase of the wound-healing process by attenuation of growth factor expression such as TGF-β1 and bFGF and subsequently by reduced collagen production.</P>

A numerical study of the effectiveness factors of nickel catalyst pellets used in steam methane reforming for residential fuel cell applications

Baek, S.M.,Kang, J.H.,Lee, K.J.,Nam, J.H. Pergamon Press ; Elsevier Science Ltd 2014 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.39 No.17

A numerical study is performed to evaluate the effectiveness factors of commercial nickel catalyst pellets commonly used in small-scale steam methane reformers for residential fuel cell applications. Based on the intrinsic reaction kinetics of the steam reforming process, the standard composition of the partially reformed gas mixture is determined as a function of the methane conversion. The heterogeneous reforming reactions inside the spherical catalyst pellets are then modeled by considering the distributed reaction, multi-component diffusion and permeation, and conductive and convective heat transfer in the porous media. Various operating conditions, including the reforming temperature, steam-to-carbon (S/C) ratio, operating pressure, and geometrical parameters, such as the pellet diameter and mean pore size, are simulated. The effectiveness factors calculated for each condition are presented as a function of the methane conversion. Finally, simple correlations for the effectiveness factors are presented, and their accuracies are assessed.

The Magnetic Properties of Rapidly Quenched Yttrium - Palladium - Borocarbides Ribbon

K. S. Kim,S. C. Yu,Y. M. Moon,J. S. Baek,W. Y. Lim 한국자기학회 1996 Journal of Magnetics Vol.1 No.1

We have studied the superconductivity of rapidly quenched YPd₂B₂C ribbons. The superconductivity in bulk YPd₂B₂C is completely suppressed by annealing as-cast ingots at higher temperatures, suggesting that the superconducting phase is metastable. The rapidly quenched sample, in the as-quenched state, shows the superconducting transition temperature of about 21 K. From our magnetic data, the value for the upper critical field H_(c2) (0) is estimated to be 10 T. The critical current density and the expected specific heat discontinuity (ΔC/γTc) were obtained to be about 10^8 A/㎡ at 10 Oe and 1.55, respectively.

DJ-1-mediated upregulation of serine palmitoyltransferase 2 controls vascular neointima via S1P autocrine

Lee, K.P.,Won, K.J.,Lee, D.H.,Lee, D.Y.,Jung, S.H.,Baek, S.,Park, T.S.,Kim, B. Elsevier/North-Holland Biomedical Press 2015 INTERNATIONAL JOURNAL OF CARDIOLOGY Vol.191 No.-

Prevalence of antimicrobial resistant Streptococcus pneumoniae serotype 11A isolates in Korea, during 2004-2013, due to the increase of multidrug-resistant clone, CC166

Baek, J.Y.,Kim, S.H.,Kang, C.I.,Chung, D.R.,Peck, K.R.,Ko, K.S.,Song, J.H. Elsevier Science 2016 INFECTION GENETICS AND EVOLUTION Vol.38 No.-

Since the introduction of the pneumococcal conjugate vaccine (PCV7) in Korea in 2003, the proportion of non-vaccine serotypes has increased. Among non-vaccine serotypes, serotype 11A is highly prevalent in Korea. We investigated the prevalence and characteristics of Streptococcus pneumoniae serotype 11A isolates in a Korean tertiary-care hospital, during 2004-2013. A total of 1579 non-duplicate clinical S. pneumoniae isolates, collected from 2004 to 2013, were included in this study. Serotype was determined by the capsular Quellung method, and in vitro susceptibility testing was performed by broth microdilution method. Multilocus sequence typing was performed to determine the genotypes of the S. pneumoniae isolates. We identified 90 serotype 11A isolates (5.7%). During this period, the proportion of serotype 11A has increased from 3.2% up to 13.2% (in 2012). Among the serotype 11A isolates, two main clonal complexes (CCs), CC166 and CC99, were identified. The increase of serotype 11A was mainly due to the increase of CC166 isolates, which have high antimicrobial resistance rates. In addition, we identified that 14 isolates, belonging to ST8279, ST9875, and ST3598 of CC166, were non-susceptible to all antimicrobial agents tested in this study. We identified the increase of S. pneumoniae serotype 11A in Korea, which mainly due to the expansion of a resistant clonal group, CC166.

Ultraviolet photodissociation spectroscopy of cold, isolated adenine complexes with a potassium cation

Baek, J.Y.,Choi, C.M.,Eun, H.J.,Park, K.S.,Choi, M.C.,Heo, J.,Kim, N.J. North Holland 2015 Chemical physics letters Vol.635 No.-

We obtain the ultraviolet photodissociation spectrum of adenine complexes with K<SUP>+</SUP> ion stored in a cold ion trap. The spectrum near the origin band of the S<SUB>0</SUB>-S<SUB>1</SUB> transition exhibits well-resolved vibronic bands, all of which are assigned from a single isomer by UV-UV hole-burning (HB) spectroscopy. Comparing the spectrum with theoretical spectra, we determine the structure of the isomer, where K<SUP>+</SUP> is bound not to 9H-adenine (A9) but to 7H-adenine (A7). We suggest that K<SUP>+</SUP>A7 ions are formed in solution through tautomerization, for which the energy barrier varies greatly depending on the binding site of the K<SUP>+</SUP> ion on A9.