protoplast-fusion에 依한 澱粉에서 Ethanol의 單段醱酵能 酵母 開發 : I. Characteristics of two yeast strains and conditions for the protoplast formation and reeneration as a preliminary step in interspecific protoplast-fusion I. Interspecific Protoplast-fusion 을 爲한 酵母菌林의 諸特性과 Protoplast 調製 및 Regeneration 條件

吳秉夏,黃殷成,李炯周,李啓瑚,朴官和,張海東,徐鉉昌 서울大學校農科大學 1984 서울대농학연구지 Vol.9 No.1

澱粉으로 부터의 alcohol 醱酵能을 增進시키기 爲하여 澱粉糖化性 菌株인 Saccharomyces diastaticus와 優秀한 alcohol 醱酵性 菌株인 Saccharomyces uvarum을 母菌株로 하여 이들간의 同屬異種間 原形質融合(interspecific protoplast fusion)을 通한 優秀한 澱粉醱酵 性 alcohol 生産性 菌株를 새로이 開發할 目的에서 다음과 같은 一漣의 實驗結果를 얻었다. S. diastaticus의 醱酵液과 S. diastaticus+S. uvarum 混合醱酵液의 風味特性등을 確認하였다. 風味成分 抽出은 methylene chloride와 diethylether를 가지고 neutral flavor fraction과 acidic flavor fraction으로 나누었고 gas chromatography를 通하여 同定 및 定量하였다. Neutral flavor fraction의 경우 S. diastaticus+S. uvarum 混合醱酵液이 S. diastaticus 醱酵液보다, ester成分中에서는 ethyl acetate와 ethyl undecanoate가 더 많았고, alcohol 成分中에서는 n-propanol과 n-butanol이 더 많았다. Acidic flavor fraction의 경우 C??~C?? fatty acid가 同定 및 定量되었는데 S. diastaticus+S. uvarum 混合醱酵液이 S. diastaticus 醱酵液보다 lauric acid, caprylic acid, capric acid 含量이 두드러지게 많았다. S. diastaticus의 glucoamylase 生産性, glucoamylase의 分離 精製, 酵素力價 그리고 酵素學的 特性에서 optimum pH는 5.0, optimum temperature는 55℃ 이었다. S. diastaticus와 S. uvarum을 母菌株로 이들 간의 protoplast fusion을 위한 基礎的인 硏究로서 두 菌株의 諸特性과 protoplast調製의 最適條件을 決定하고 protoplast의 regeneration 條件의 確立을 도모하였다.두 菌의 生育曲線에서 모두 培養開始 7~8 時間만에 對數期 中期에 到達되었으므로 protoplast 調製는 이 時期의 細胞를 쓰기로 하였다. Generation time은 S. diastaticus가 1.04, S. uvarum이 1.38 時間이었다. 細胞의 크기는 S. diastaticus 44.10?㎛³, S. uvarum 99.67㎛³로 S. uvarum이 2倍나 컸다. DNA 含量은 細胞 當 S. diastaticus 44.3fg, S. uvarum 37.6fg이었다. 30% glucose 및 soluble starch에 대한 두 菌株의 ethanol 醱酵能은 glucose에 對하여 S. uvarum 11.4%, S. diastaticus 8.9% 이었고 soluble starch에 對하여는 S. diastaticus 만이 6.9%이었다. 두 菌株는 generation time, 細胞크기 및 DNA 含量 等으로 보아 diploid strain임을 알 수 있었고, 融合株 選拔을 위한 marker 로는 Sacch. uvarum의 melibiose 資化能의 차이를 利用할 수 있음을 밝혔다. Protoplast의 調製에는 β-glucuronidase와 Zymoyase를 使用하였는데 두 酵素 反應最適條件은 β-glucuronidase는 pH 8.0에서 10% 濃度의 溶液으로, Zymolyase는 pH7.5에서 20㎛/ml의 濃度의 溶液으로 하여 모두 70分間 處理하는 것으로 決定하였으나 이 정도의 處理時間에서는 protoplast가 극히 不安定하게 되어 regeneration frequency가 떨어지는 것을 確認하였으며, 特히 Zymolyase 處理로 얻어진 protoplast의 regeneration率이 낮은 것은 Zymolyase中에 不純物로 微量 混在한 protease가 protoplast의 노출된 membrane-bound protein을 分解함으로써 protoplast를 破壞시키기 때문인 것으로 추측되었다. 融合實驗에 利用할 수 있을 정도의 regeneration frequency를 얻기 위해서는 Zymolyase를 45分間 處理하여 얻은 protoplast를 1.5%의 polyvinylpyrrolicone이 加해진 OYPD培地에서 重層法으로 展開하여 regeneration시키는 것이 좋은 것으로 판명되었다. As preliminary steps of protoplast fusion between Saccharomyces diastaticus and S. uvarum to develop a fusant of higher ethanol production from starch, characteristics of the two presumptive parent strains, optimal conditions for protoplast preparation and conditions for highrer regeneration frequency were investigated. To determine flavor characteristics of the parent strains, neutral and acidic flavor fractions were extracted from liquids fermented by S. diastaticus and S. diastaticus + S. uvarum with methylene chloride and diethly ether. The liquid by the mixed culture produced more ethly acetate, ethyl undecanoate, n-propanol, n-butanol, lauric acid, caprylic acid and capric acid than that by S. diastaticus. Glucoamylase from S. diastaticus was purified and activity, productivity, and characteristics were determined. Optimum conditions for the enzyme were pH 5.0 and 55℃. The two strains reached logarithmic phase in 7-8h during growth and the generation time was 1.04 in S. diastaticus and 1.38 in S. uvarum. Cell size and DNA content per cell of S. diastaticus were 44.10㎛³and 44.3 fg, and for S. uvarum, 99.67㎛³and 37.6fg. Ethanol productivities of S. diastaticus were 8.9% from 30% glucose and 6.9% from 30% starch and 11.4% from glucose with S. uvarum. Through determination of generation time, cell size, and DNA content per cell, both strains appeared as diploids, and differences in assimilability of melibiose and soluble starch of the two strains were selected as markers to determine the fusant. The optimal condition for protoplast formation was treatment of both strains with 10% ß-glucuronidase at pH 8.0 or 20㎍/ml Zymolyase at pH 7.5 for 70 min. While the regeneration frequencies were very low at 70min exposure to Zymolyase because of the instability of protoplasts, the yeasts treated for 45min were better for regeneration. The regeneration frequencies were also enhanced by 3-6 times when the regeration was carried out with 1.5% polyvinylpyrrolidone which stabilized protoplasts.

Salmonella Typhi, Salmonella Typhimurium 및 Salmonella Enteritidis의 항균제 감수성 (1997)

신영학,유정식,김기상,정동준,오경수,이점규,이상원,이근영,박미선,이복권,김호훈 국립보건연구원 1998 국립보건원보 Vol.35 No.-

Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis

Yu, K‐,H.,Hong, K‐,S.,Lee, B‐,C.,Oh, M‐,S.,Cho, Y‐,J.,Koo, J‐,S.,Park, J‐,M.,Bae, H‐,J.,Han, M‐,K.,Ju, Y‐,S.,Kang, D‐,W.,Appelros, P. Blackwell Publishing Ltd 2011 Acta neurologica Scandinavica Vol.123 No.5

<P>Yu K‐H, Hong K‐S, Lee B‐C, Oh M‐S, Cho Y‐J, Koo J‐S, Park J‐M, Bae H‐J, Han M‐K, Ju Y‐S, Kang D‐W, Appelros P, Norrving B, Terent A. Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis. 
Acta Neurol Scand: 2011: 123: 325–331. 
© 2010 John Wiley & Sons A/S.</P><P><B>Background – </B> It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case‐fatality between two PSM cohorts of Sweden and Korea.</P><P><B>Methods – </B> Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one‐to‐one matching based on propensity scores of each patient.</P><P><B>Results – </B> After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90‐day case‐fatality was identical 6.2% (HR 0.997, 95%CI 0.905–1.099) in Sweden and Korea.</P><P><B>Conclusions – </B> No difference is found in the 90‐day case‐fatality in propensity score‐matched Swedish and Korean patients with ischemic stroke.</P>

Salmonella Typhi, Salmonella Enteritidis 및 Salmonella Typhimurium균에 대한 Phage typing 및 antibiogram 분석

신영학,유정식,오경수,이점규,이상원,고운영,양병국 국립보건연구원 2000 국립보건원보 Vol.37 No.-

生體內 藥劑耐性 및 Plasmid 傳達에 關한 硏究

金鎬薰,李明遠,李英姬,金基湘,兪天權,吳明燉,李悌煥,李点揆,琴東吉,鄭泰華,李潤台 국립보건연구원 1989 국립보건원보 Vol.26 No.

Bioequivalence Study of a New Fixed-dose Combination Tablet Containing S-Amlodipine Nicotinate and Olmesartan Medoxomil in Healthy Korean Male Subjects

Oh, M.J.,Hwang, H.H.,Kim, H.G.,Lee, G.H.,Cho, Y.S.,Lee, S.Y.,Kang, S.Y.,Cho, K.H.,Lee, Y.Y.,Lee, Y.J.,Jang, C.G.,Lee, S.Y. Excerpta Medica] ; Elsevier Science Ltd 2017 Clinical therapeutics Vol.39 No.7

Purpose: A fixed-dose combination (FDC) pill of amlodipine (relatively old calcium channel blocker as dihydropyridine) and olmesartan (relatively new angiotensin II receptor blocker) is used for hypertension that is not adequately controlled with a single-formulation drug. Because the FDC is a one-pill formulation, and amlodipine and olmesartan have different mechanisms of action, it is expected to improve patients' medication compliance and have an increased blood pressure-lowering efficacy. The purpose of this study was to assess the safety profile and the bioequivalence of two different FDC formulations [amlodipine besylate/olmesartan medoxomil 10/40 mg (reference product) and S-amlodipine nicotinate/olmesartan medoxomil 5/40 mg (test product)]. Methods: A randomized, open-label, single-dose, 2-treatment, 2-way, and 2-period crossover study, including a 3-week washout period, was performed in 32 healthy Korean male volunteers. To analyze the concentration of S-amlodipine or olmesartan, plasma samples were collected up to 144 hours after the dose for S-amlodipine and 48 hours after the dose for olmesartan. Pharmacokinetic parameters, including the C<SUB>max</SUB> and the area under the curve from time 0 to the last measurable concentration (AUC<SUB>0-last</SUB>) for the time versus concentration plot, were calculated. Analysis of variance for bioequivalence was conducted using C<SUB>max</SUB> and AUC<SUB>0-last</SUB> converted to log scale, and the mean ratios and 90% CIs were determined. Safety data included analysis of adverse events (AEs), vital signs, physical examinations, clinical laboratory test, and 12-lead ECGs. Findings: Of the 32 enrolled participants, 29 healthy volunteers completed the study. For both S-amlodipine and olmesartan, the main pharmacokinetic parameters were all within the acceptable range for regulatory bioequivalence. The 90% CIs for the geometric mean ratios of C<SUB>max</SUB> and AUC<SUB>0-last</SUB> were 0.8766 to 0.9760 and 0.8288 to 0.9224, respectively, for S-amlodipine and 0.9097 to 1.1229 and 0.8904 to 1.0407, respectively, for olmesartan. Hypotension was the most frequent AE, and it was observed in 4 volunteers with the test product and 7 volunteers with the reference product. Both the test and reference formulations were well tolerated. Implications: The present study demonstrates that the newly developed FDC product (test drug) and the conventional FDC product (reference drug) have comparable pharmacokinetic characteristics in healthy adult male volunteers. Both the test and reference products indicated good tolerance in this population, and no serious AEs were observed.

Sphingomonas aestuarii sp. nov., isolated from tidal flat sediment

Roh, S. W.,Kim, K.-H.,Nam, Y.-D.,Chang, H.-W.,Kim, M.-S.,Oh, H.-M.,Bae, J.-W. Microbiology Society 2009 International journal of systematic and evolutiona Vol.59 No.6

<P>A novel bacterium (strain K4(T)) belonging to the genus Sphingomonas was isolated from tidal flat sediment in Korea. Its morphology, physiology, biochemical features and 16S rRNA gene sequence were characterized. Colonies of this strain are yellow in colour and the cells are rod-shaped, exhibiting negative Gram staining. The strain grows at 0-5 % (w/v) NaCl and 20-35 degrees C, with optimal growth occurring at 0 % (w/v) NaCl and 30 degrees C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain K4(T) is associated with the genus Sphingomonas. Within the phylogenetic tree, this novel strain shares a branching point with Sphingomonas asaccharolytica Y-345(T), with which it shares 97.3 % 16S rRNA gene sequence similarity. The polyamine pattern predominantly contains the Sphingomonas-specific triamine sym-homospermidine. Combined analysis of 16S rRNA gene sequences, DNA-DNA relatedness, physiological and biochemical test results identified genotypic and phenotypic differences between strain K4(T) and other Sphingomonas species. On the basis of these differentiating features, it is concluded that strain K4(T) (=KCTC 22050(T)=DSM 19475(T)) represents a novel species of the genus Sphingomonas, for which the name Sphingomonas aestuarii sp. nov. is proposed.</P>

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>

Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells

Yun, S.M.,Woo, S.H.,Oh, S.T.,Hong, S.E.,Choe, T.B.,Ye, S.K.,Kim, E.K.,Seong, M.K.,Kim, H.A.,Noh, W.C.,Lee, J.K.,Jin, H.O.,Lee, Y.H.,Park, I.C. North-Holland 2016 Molecular and cellular endocrinology Vol.422 No.-

Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells.

Control of Thermoelectric Properties through the addition of Ag in the Bi0.5 Sb1.5 Te3Alloy

( J. K. Lee ),( S. D. Kim ),( M. W. Oh ),( S. H. Cho ),( B. K. Min ),( H. W. Lee ),( M. H. Kim ) 대한금속재료학회 ( 구 대한금속학회 ) 2010 ELECTRONIC MATERIALS LETTERS Vol.6 No.4

In this study, the thermoelectric properties of the Ag-doped Bi0.5Sb1.5Te3 compounds were investigated in the temperature range from 323 K to 573 K. Ingots were fabricated by a conventional melting process and the powder crushed from ingots was then sintered using a hot-pressing method. The temperature dependence of the Seebeck coefficient and the electrical conductivity of the Ag-doped Bi0.5Sb1.5Te3compound are characteristic of degenerate semiconductors, which is fairly different from the conventional Bi0.5Sb1.5Te3 compound. The power factor (α 2 σ) of the quaternary compound was larger than that of the ternary, which is mainly due to the increase in the electrical conductivity with doping content of Ag. The thermal conductivity was greater than that of the Ag-freeBi0.5Sb1.5Te3compound in the temperature range from 323 K to 523 K. The lattice thermal conductivity showed low values throughout the temperature range. The maximum value of the dimensionless figure of merit (ZT) of the 0.05 wt. % Ag-doped compound and the ternary alloy were 1.2 at 373 K and 0.88 at 323 K, respectively. Each of the maximum peak ZT shifts to a higher temperature region with increases in the doping content of Ag. This is likely due to the control of the lattice thermal conductivity by the twin structure, which had a nano-ordered layer.