Precise determination of the lithium isotope ratio in geological samples using MC-ICP-MS with cool plasma

Choi, Min Seok,Ryu, Jong-Sik,Park, Ha Yan,Lee, Kwang-Sik,Kil, Youngwoo,Shin, Hyung Seon The Royal Society of Chemistry 2013 Journal of analytical atomic spectrometry Vol.28 No.4

<P>Lithium has two naturally occurring isotopes, <SUP>6</SUP>Li and <SUP>7</SUP>Li, with approximate relative abundances of 7.5% and 92.5%, respectively. Due to large Li isotope variations in nature, lithium isotopes have the potential to reveal important information relevant to nuclear technology, biomedicine, astrophysics, and geochemistry. With the advent of multi-collector inductively coupled mass spectrometry (MC-ICP-MS), studies of Li isotopes have largely focused on the analysis of geological materials, with varying degrees of accuracy. However, this technique has often been affected by either baseline interferences or isobaric interferences on mass 6 and 7 during ionization in Ar plasma, which is mainly due to the Li compound with hydrogen gas, and double-charged nitrogen and carbon ions at higher levels of RF power. In this study, we reduced baseline interferences in Ar plasma using a cool plasma (∼800 W) technique with a X-type cone. Lithium was separated using a cation exchange column (BioRad AG50W-X8, 200–400 mesh) with a mixture of 6 N HNO<SUB>3</SUB> and 80% methanol at <0.2 mL min<SUP>−1</SUP> elution speed. The short-term reproducibility of <I>δ</I><SUP>7</SUP>Li values of the NASS-5 seawater standard was 30.55 ± 0.45‰ (2<I>σ</I>, <I>n</I> = 15). Measured <I>δ</I><SUP>7</SUP>Li values of rock and seawater standards ranged from 2.48 to 30.55‰, in good agreements with reported values.</P> <P>Graphic Abstract</P><P>Average <I>δ</I><SUP>7</SUP>Li values of a pure L-SVEC Li solution and one passed through the column were 0.00 ± 0.23‰ (2<I>σ</I>, <I>n</I> = 26) and ¬0.01 ± 0.20 ‰ (2<I>σ</I> , <I>n</I> = 9), respectively, indicating that our chemical separation procedure for Li induces no mass fractionation. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2ja30293d'> </P>

인진쑥 배지에서 배양한 노루궁뎅이버섯 균사체 추출물(HEAC)의 알코올 대사촉진 활성

최원식(Choi, Won-Sik),장도연(Jang, Do-Yoen),차경민(Cha, Kyung-Min),박천규(Park, Chun-Kyu) 한국산학기술학회 2008 한국산학기술학회논문지 Vol.9 No.1

인진쑥 배지에서 배양한 노루궁뎅이버섯(HEAC), 노루궁뎅이버섯과 인진쑥 추출물들의 음주 후 체내 알코올 농도의 감소 효과를 확인하였으며, 또한 혈중 알코올 탈수소효소 및 아세트알데히드 탈수소효소의 활성을 조사하여 알코올 분해 활성을 조사하였다. 체내 알코올 농도 측정결과 HEAC의 경우 170분, 노루궁뎅이 버섯 추출물은 210 분후에 혈중 알코올이 검출되지 않았다. 또한, HEAC는 알코올 탈수소효소 활성에서 대조군 보다 시간에 따라 154%, 노루궁뎅이버섯 추출물은 148%로 비교적 높은 활성을 나타내었다. 아세트알데히드 탈수소활성에서는 HEAC와 노루궁뎅이버섯 추출붙이 대조구에 비해 104~111%이상의 효소활성이 유지되는 것을 확인하였으며 이들 추출물들은 알코올 분해 촉진작용이 매우 우수함을 알았다. Alcohol concentration in the blood was effectively decreased by extracts from Hericium erinaceum hypha cultivated with Artermisia capillaris medium(HEAC), Hericium erinaceum hypha and Artermisia capillaris after dirnking. Also, the activities of alcohol dehydrogenase and acetaldehyde dehydrogenase in the blood was studied. As a result of testing an alcohol concentration in the blood, the alcohol in the blood was not detected after 170 min. in case of HEAC and after 210 min. in case of Hericium erinaceum. Compared to control, each activities of alcohol dehydrogenase of HEAC and Hericium erinaceum hypha was showed up to 154% and 148% respectively. The activities of the acetaldehyde dehydrogenase of both extracts from HEAC and Hericium erinaceum was maintained in the range of 104 to 110% compared to control. In conclusion, such extracts represent significant effect to facilitate decomposition of alcohol.

대장직장 종양에 대한 내시경 점막하 절제술의 연대순 임상 결과와 학습 곡선

이상민 ( Sang Min Lee ),김은수 ( Eun Soo Kim ),박경식 ( Kyung Sik Park ),조광범 ( Kwang Bum Cho ),김동춘 ( Dong Choon Kim ),강유진 ( Yu Jin Kang ),이유진 ( Yoo Jin Lee ),이정민 ( Jung Min Lee ),최은성 ( Eun Sung Choi ),최재혁 ( Ja 대한소화기학회 2014 대한소화기학회지 Vol.64 No.4

Background/Aims: Endoscopic submucosal dissection (ESD) is an effective procedure for en-bloc curative resection of the colorectal tumor. As it requires high technical skills and experience in therapeutic endoscopy, it is important to understand learning curve of ESD technique. The aim of this study was to retrospectively describe the clinical results of ESD and to evaluate learning curve for the ESD of colorectal tumors. Methods: A total of 90 patients with 90 colorectal neoplasms, who had undergone ESD at a tertiary referral hospital from July 2009 to December 2012, were enrolled. The ESD was performed by a single endoscopist. All ESD cases were divided into three periods: first, cases 1-30; second, cases 31-60; and third, cases 61-90. Results: The en-bloc resection rates in third period (100%) was significantly higher than that of the first (93.3%) and second period (80%) (p=0.025). The perforation rate in third period (0%) also significantly decreased compared with that of the first (13.3%) and second period (20%) (p=0.032). To calibrate the difference of tumor size among periods, proficiency was calculated, as the procedure time per specimen area (min/cm2). The proficiency in third period (4.3) was significantly shorter than that of the first (16.8) and second period (10.2) (p=0.004). Conclusions: The learning curve of colorectal ESD in our study shows that at least 60 cases of ESD have to be conducted to acquire sufficient skill of degree without perforation. (Korean J Gastroenterol 2014;64:198-205)

Effects of Chungkookjang Extract on Growth Hormone Secretion from GH3 Mouse Pituitary Cell and Growth Hormone Receptor Signaling Pathway

Sun Il Choi(최선일),Ji Eun Kim(김지은),In Sik Hwang(황인식),Hye Ryun Lee(이혜련),Young Ju Lee(이영주),Hong Joo Son(손홍주),Dong Seob Kim(김동섭),Kyu Min Park(박규민),Dae Youn Hwang(황대연) 한국생명과학회 2012 생명과학회지 Vol.22 No.9

뇌하수체 전엽에서 성장호르몬의 생산과 분비는 세포의 분열과 분화 그리고 이동을 조절하는 몇 가지 천연물질에 의해 유도된다. 따라서 발효과정을 통해 제조된 청국장이 성장호르몬의 대사에 미치는 영향을 평가하기 위하여 성장호르몬 분비능과 반응성을 뇌하수체 세포와 성장호르몬 표적세포에서 관찰하였다. 6가지 종류의 콩 품종으로 제조된 청국장 추출물 중에서, 대원, 대풍, 태광의 3종류 청국장 추출물은 5 mg/ml 농도에서 GH3 세포로부터 성장호르몬의 분비를 촉진하였다. 비록 세포 생존능은 이러한 추출물에 의해 유의적인 변화가 유도되지 않았으나, 성장호르몬의 분비량은 청국장 추출물의 농도에 의존적으로 증가하였다. 또한 성장호르몬의 표적 기관으로부터 유래된 MG63과 HepG2 세포는 GH3로부터 수집된 조건적 배양액에 의해 유의적으로 활성화되었다. 또한 이러한 세포에서 STAT5 발현은 대원 청국장 추출물을 처리 후, 15분 혹은 30분부터 세포질에서 유의적으로 증가하였으며, p-STAT5는 핵에서 30분 혹은 60분부터 증가하였다. 따라서 이러한 결과는 3가지 종류의 청국장 추출물은 성장호르몬의 분비를 촉진시키며, 청국장의 조건적 배양액은 성장호르몬 표적세포에서 신호전달을 유도함을 제시하고 있다. The production and secretion of growth hormone (GH) in the anterior pituitary gland can be induced by several natural products to control cell proliferation, differentiation, and migration. To investigate whether Chungkookjang (CKJ) produced by the fermentation process affects GH-related metabolism, the secretion and the response of GH were observed in pituitary cells and GH target cells. Among six CKJs manufactured by different strains of glycine max, only three CKJs, including Daewon (DW), Daepung (DP), and Taegwang (TG), induced GH secretion from GH3 cells at 5.0 mg/ml concentration. There were no significant changes detected in the viability of any of the cells treated with these CKJs. In addition, the increase in GH secretion from the GH3 cells was dependent on the concentration of the three types of CKJs. The proliferation of cell lines, including MG63 and HepG2 cells, that originated from those derived from the GH target organs was significantly activated by treatment with the GH-containing conditional medium (GCM) harvested from the three CKJ-treated GH3 cells, although their induction rate was different from each other. In these cells, p-STAT5 was maximally translocated into the nucleus of MG63 cells 30 min after DW treatment, while it was translocated in HepG2 cells at 60 min. These results suggest that these three types of CKJ could enhance the secretion of GH, as well as the GCM-derived response, in the two target organs.

Purification and Characterization of Helicobacter pylori ${\gamma}$-Glutamyltranspeptidase

Song, Jae-Young,Choi, Yeo-Jeong,Kim, Jeong-Min,Kim, Yoo-Ree,Jo, Jin-Seong,Park, Jin-Sik,Park, Hee-Jin,Song, Yun-Gyu,Lee, Kon-Ho,Kang, Hyung-Lyun,Baik, Seung-Chul,Youn, Hee-Shang,Cho, Myung-Je,Rhee, Kw The Korean Society for Microbiology 2011 Journal of Bacteriology and Virology Vol.41 No.4

Gamma-glutamyltranspeptidase (GGT) was purified to electrophoretic homogeneity from the cell extract of H. pylori. The purified enzyme consisted of heavy and light subunits with molecular weights of 38 kDa and 21 kDa, respectively. N-terminal amino acid sequence of heavy and light subunits revealed that H. pylori GGT was processed into 3 parts for a signal peptide of 27 amino acid residues, a heavy subunit of 352 residues, and a light subunit of 188 residues during translation. The reaction rate for hydrolysis of ${\gamma}$-GpNA was 84.4 ${\mu}mol/min$ per milligram of protein, and that for the ${\gamma}$-glutamyl transfer from ${\gamma}$-GpNA to gly-gly was 23.8 ${\mu}mol/min$ per milligram of protein. The apparent Km values of H. pylori GGT for ${\gamma}$-glutamyl compounds were on the order of $10^{-3}$ to $10^{-4}$ M and those for acceptor peptides and amino acids were on the order of $10^{-1}$ to $10^{-2}$ M. The GGT protein kept approximately 80% of the initial enzymatic activity on incubation at $60^{\circ}C$ for 15 min. The optimum temperature and pH for reactions of both hydrolysis and transpeptidation were $40^{\circ}C$ and 9.0, respectively. The transpeptidation and hydrolysis reactions catalyzed by H. pylori GGT were strongly inhibited by L-Gln and moderately inhibited by L-Ala, L-Ser, ${\beta}$-chloro-L-Ala, and L-Glu. These results demonstrated that the biochemical properties of H. pylori GGT are different from those of other bacterial GGTs. Further, H. pylori GGT might degrade glutathione in the gastric mucous layer of humans if the enzyme could be secreted in the bacterial niches.

수열법으로 성장한 ZnO Nanorod/ZnO/Si(100)의 특성

정민호,진용식,최성민,한덕동,최대규,Jeong, Min-Ho,Jin, Yong-Sik,Choi, Sung-Min,Han, Duk-Dong,Choi, Dae-Kue 한국재료학회 2012 한국재료학회지 Vol.22 No.4

Nanostructures of ZnO, such as nanowires, nanorods, nanorings, and nanobelts have been actively studied and applied in electronic or optical devices owing to the increased surface to volume ratio and quantum confinement that they provide. ZnO seed layer (about 40 nm thick) was deposited on Si(100) substrate by RF magnetron sputtering with power of 60 W for 5 min. ZnO nanorods were grown on ZnO seed layer/Si(100) substrate at $95^{\circ}C$ for 5 hr by hydrothermal method with concentrations of $Zn(NO_3)_2{\cdot}6H_2O$ [ZNH] and $(CH_2)_6N_4$ [HMT] precursors ranging from 0.02M to 0.1M. We observed the microstructure, crystal structure, and photoluminescence of the nanorods. The ZnO nanorods grew with hexahedron shape to the c-axis at (002), and increased their diameter and length with the increase of precursor concentration. In 0.06 M and 0.08 M precursors, the mean aspect ratio values of ZnO nanorods were 6.8 and 6.5; also, ZnO nanorods had good crystal quality. Near band edge emission (NBE) and a deep level emission (DLE) were observed in all ZnO nanorod samples. The highest peak of NBE and the lower DLE appeared in 0.06 M precursor; however, the highest peak of DLE and the lower peak of NBE appeared in the 0.02 M precursor. It is possible to explain these phenomena as results of the better crystal quality and homogeneous shape of the nanorods in the precursor solution of 0.06 M, and as resulting from the bed crystal quality and the formation of Zn vacancies in the nanorods due to the lack of $Zn^{++}$ in the 0.02 M precursor.

900MHz대 수동형 RFID 휴대 리더스 소형 원편파 안테나

최익권,강민식,이우태 충북대학교 컴퓨터정보통신 연구소 2006 컴퓨터정보통신연구 Vol.14 No.1

본 논문에서는 휴대용 RFID(Radio Frequency IDentification)리더안테나로 중심주파수 911MHz인 소형 원편파 마이크로스트립안테나를 설계 제작하였다. 안테나는 대칭모서리가 절단된 정사각형 형태를 채택하였으며 유전체기판은 유전율 4.4, 손실탄젠트 0.02인 FR4기판을 사용하였다. 설계에는 상용 시뮬레이션 도구인 ANSOFT 사의 DESIGNER V2 와 HFSS를 사용하였다. 제작된 안테나는 두께가 8mm, 크기가 130mm × 130mm로 소형이면서, -10dB 대역폭이 870MHz ~ 950MHz, 이득 4.4dB 그리고 축비가 3.42 dB로 비교적 우수한 특성을 가짐을 측정을 통해 확인하였다. In this paper, small size circularly polarized microstrip patch antenna for portable RFID reader antenna with a center frequency 911MHz is designed and fabricated. The antenna is of a corner truncated type and is fabricated with FR4 dielectric board of dielectric constant 4.4 and loss tangent 0.02. The DESIGNER V2 and HFSS simulation tools of ANSOFT corporation are used in the antenna design. The fabricated antenna is 8mm thick and as small as 130mm by 130mm in size. It's -10dB bandwidth, gain and axial ratio are shown to be 870MHz ~ 950MHz, 4.4dB and 3.42dB, respectively, by measurements.

Endoscopic submucosal tunnel dissection salvage technique for ulcerative early gastric cancer.

Choi, Hyuk Soon,Chun, Hoon Jai,Seo, Min Ho,Kim, Eun Sun,Keum, Bora,Seo, Yeon Seok,Jeen, Yoon Tae,Lee, Hong Sik,Um, Soon Ho,Kim, Chang Duck,Ryu, Ho Sang WJG Press 2014 WORLD JOURNAL OF GASTROENTEROLOGY Vol.20 No.27

<P>Endoscopic submucosal dissection is an effective treatment modality for early gastric cancer (EGC), though the submucosal fibrosis found in ulcerative EGC is an obstacle for successful treatment. This report presents two cases of ulcerative EGC in two males, 73- and 80-year-old, with severe fibrosis. As endoscopic ultrasonography suggested that the EGCs had invaded the submucosal layer, the endoscopic submucosal tunnel dissection salvage technique was utilized for complete resection of the lesions. Although surgical gastrectomy was originally scheduled, the two patients had severe coronary heart disease, and surgeries were refused because of the risks associated with their heart conditions. The endoscopic submucosal tunnel dissection salvage technique procedures described in these cases were performed under conscious sedation, and were completed within 30 min. The complete en bloc resection of EGC using endoscopic submucosal tunnel dissection salvage technique was possible with a free resection margin, and no other complications were noted during the procedure. This is the first known report concerning the use of the endoscopic submucosal tunnel dissection salvage technique salvage technique for treatment of ulcerative EGC. We demonstrate that endoscopic submucosal tunnel dissection salvage technique it is a feasible method showing several advantages over endoscopic submucosal dissection for cases of EGC with fibrosis. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.</P>

수근관 증후군의 국소 스테로이드 주사

조민규,이성훈,강은영,전평식,최영태 大韓再活醫學會 2000 Annals of Rehabilitation Medicine Vol.24 No.5

건축 리모델링 프로젝트 리스트 요인 분석을 통한 체크리스트 개발에 관한 연구 : Based on the Analysis of Risk Causes

최병호,구민경,박찬식 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

Delay and cost overrun have happened continuously in remodeling projects and domestic constructions do not grasp about the risk's reason for cost and time. Therefore the study derives some risk causes which bring about delay and cost overrun through some documentary records and some interviews. And then it analyzes extracted items by statistical method and divides the items which is produced some consequences those are in beyond degree as a general area and as an important area. Finally, the research suggests the items to improve management of the duration and about checklist.