• Title/Summary/Keyword: $K_{trans}$

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Effect of Temperature on Composition of Monohydroperoxide Isomers Formed in Oxidation of Methyl Linoleate (Methyl Linoleate의 산화중 형성된 Monohydroperoxide 이성체들의 조성에 미치는 온도의 영향)

  • Kim, In-Hwan;Kim, Chul-Jin;Kim, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.28 no.3
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    • pp.440-445
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    • 1996
  • An attempt was made to study the relative composition of Monohydroperoxide isomers of methyl linoleate oxidized to different peroxide values at 60, 90, 120 and $150^{\circ}C$, respectively. HPLC was used to analyze and isolate the monohydroperoxide isomers fractionated by silica gel column after reduction with NaBH.. GC-MS was used to identify four monnhydroperoxide isomers as trimethylsilyl (TMS) in mixtures of oxidized methyl linoleate In the geometrical isomers, the proportions of 9/13-OOH-trans, trant-diene were higher than those of 9/13-OOH-cis, trans-diene at $60^{\circ}C$ and $90^{\circ}C$. However in the initial stage at $150^{\circ}C$, the proportions of 9/13-OOH-cis, trans-diene were slightly higher than those of 9/13-OOH-trans, trans-diene. In case of positional isomers, equal proportions of 9-OOH-10, 12-diene and 13-OOH-9, 11-diene were found in all samples of methyl linoleate oxidized at different temperatures and peroxide levels.

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High Level of Trans-Resveratrol, a Natural Anti-Cancer Agent, Found in Korean Noul Red Wine

  • KIM, KWANG-SEOK;SA-YOUL GHIM;YOUNG-BAE SEU;BANG-HO SONG
    • Journal of Microbiology and Biotechnology
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    • v.9 no.5
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    • pp.691-693
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    • 1999
  • Resveratrol (trans-3,5,4'-trihydroxystilbene), a phenolic substance present in both grapes and wines, has been reported to have certain pharmacological effects. Using an ethylacetate-phase extraction followed by a high performance liquid chromatographic analysis, the concentration of trans-resveratrol was measured in 9 red wines commercially available in Korea, including the Korean red wine (Noul). Noul red wine with a 1998 vintage had a trans-resveratrol concentration of 3.3 ㎎/l, which was rather higher than the concentrations found in other wines (0.19-2.45 ㎎/l) with the exception of the French wine, J. P. Chenet (3.39 ㎎/l). In addition, the grapes of Vitis labrusca cv. Sheridan cultivated in the Kyungsan area showed a trans-resveratrol content of 6.4 ㎎/㎏.

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Fe-H…H-C Dihydrogen Bondings: Synthesis and Structure of trans-[FeH(NCSe)(dppe)2](dppe=Ph2 PCH2 CH2 PPh2 (Fe-H…H-C 이수소 결합: trans-[FeH(NCSe)(dppe)2](dppe=Ph2 PCH2 CH2 PPh2의 합성 및 구조)

  • Baek, Ji Yeong;Han, Won Seok;Lee, Sun Won
    • Journal of the Korean Chemical Society
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    • v.46 no.5
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    • pp.427-436
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    • 2002
  • Reaction of $trans-[FeHCl(dppe)_2]$ (1) with KSeCN led to the formation of $trans-[FeH(NCSe)(dppe)_2](2).$ Compound 2 $·CH_2Cl_2$ was structurally characterized by X-ray diffraction, in which the hydride ligand appears to be involved in the dihydrogen bonding of the type M-H${\cdot}$${\cdot}$${\cdot}$H-C.

Ab initio Calculation for Photochemistry of Psoralens (소랄렌의 광화학 반응에 대한 Ab initio 계산)

  • Kim, Ja-Hong;Kwon, O-Hyung
    • Journal of the Korean Chemical Society
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    • v.53 no.3
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    • pp.244-256
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    • 2009
  • The psoralen-pyrimidine base complexes resulting from interstrand cross-linking through $C_4$-cycloaddition is studied by ab initio and DFT methods. The results indicate that in the case of the molecular complex formation between psoralens and pyrimidine base, the most probable photocycloadditions are 8-MOP< >Thy, Ps< >Cyt and Ps< >Thy. The geometries of photoadducts were optimized at the HF levels and ${\Delta}{G^{\circ}}$ were calculated. The photocycloadduct was inferred to be a C4-cycloaddition product with the stereochemistry of trans-syn 8-MOP< >Thy, trans-anti Ps(3, 4)< >Cyt, trans-anti Ps(12, 13)< >Cyt, trans-syn Ps(3, 4)< >Thy, trans-syn Ps(12, 13)< >Thy, trans-anti Ps(12, 13)< >Ps(12, 13), cis syn, cis anti Thy< >(3, 4)Ps(12, 13)< >Thy.

Pressure Effect on the Aquation of trans-[Cr$(en)_2Br_2]^+$ and trans-$[Cr(tn)_2Br_2]+^$ Ions (trans-[Cr$(en)_2Br_2]^+$ 및 trans-$[Cr(tn)_2Br_2]+^$ 착이온의 수화반응에 미치는 압력의 영향)

  • Jong Jae Chung;Park Kyung Suk
    • Journal of the Korean Chemical Society
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    • v.30 no.4
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    • pp.341-344
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    • 1986
  • The rate for the aquation of trans-[Cr$(en)_2Br_2]^+$ and trans-$[Cr(tn)_2Br_2]+^$ ions in the aqueous solution has been measured by the conductometric method at various pressures and temperatures. The rate constants are increased with increasing temperature and decreased with increasing pressure. Activation volumes are all positive values and lie in the limited range +1.6 ∼ +2.3Oc$m^3$/mole for trans-[Cr$(en)_2Br_2]^+$ and +1.30 ∼ +1.92c$m^3$/mole for trans-$[Cr(tn)_2Br_2]+^$. Activation entropies have small negative values while activation compressibilities have small positive values. From the above results, we may deduce that the mechanism for the aquation of these complexes is the $I_d$ mechanism.

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Interaction of a 22 kDa Peptidyl Prolyl cis/trans Isomerase with the Heat Shock Protein DnaK in Vibrio anguillarum

  • Kang, Dong Seop;Moon, Soo Young;Cho, Hwa Jin;Lee, Jong Min;Kong, In-Soo
    • Journal of Microbiology and Biotechnology
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    • v.27 no.3
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    • pp.644-647
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    • 2017
  • Peptidyl prolyl cis/trans isomerases (PPIases) catalyze the cis/trans isomerization of peptidyl-prolyl peptide bonds preceding prolines. We investigated the protein-protein interaction between a 22 kDa PPIase (VaFKBP22, an FK506-binding protein) and the molecular chaperone DnaK derived from Vibrio anguillarum O1 (VaDnaK) using GST pull-down assays and a bacterial two-hybrid system for in vivo and in vitro studies, respectively. Furthermore, we analyzed the three-dimensional structure of the protein-protein interaction. Based on our results, VaFKBP22 appears to act as a cochaperone of VaDnaK, and contributes to protein folding and stabilization via its peptidyl-prolyl cis/trans isomerization activity.

INDEFINITE TRANS-SASAKIAN MANIFOLD WITH A TRANSVERSAL HALF LIGHTLIKE SUBMANIFOLD

  • Jin, Dae Ho
    • East Asian mathematical journal
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    • v.33 no.5
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    • pp.533-542
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    • 2017
  • We study the geometry of indefinite trans-Sasakian manifold ${\bar{M}}$ admitting a half lightlike submanifold M such that the structure vector field of ${\bar{M}}$ belongs to the transversal vector bundle of M. We prove several classification theorems of such an indefinite trans-Sasakian manifold.

Quantitative Analysis of trans-Resveratrol in Red Wines by Solid Phase Extraction and LC/MS (고체상 추출법과 LC/MS를 이용한 적포도주 중의 trans-Resveratrol 분석)

  • Park, Gyo-Beom;Moon, Hyoung-Sil;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.16 no.2
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    • pp.125-133
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    • 2003
  • In order to determine the contents of trans-resveratrol in red wine, which was mainly consumed in Korea, both LC/MS-ESI and LC/MS-APCI methods were used after solid-phase (Sep-Pak $C_{18}$-cartridges) extraction. The contents of trans-resveratrol obtained by LC/MS-ESI were detected in the range of $0.06-4.31{\mu}g/mL$. The recoveries were ranged from 88.4 to 97.9%. The values of relative standard deviation were ranged from 0.6 to 4.6% and the detection limit was $0.001{\mu}g/mL$. The contents of trans-resveratrol obtained by LC/MS-APCI were detected in the range of $0.09-4.02{\mu}g/mL$ and the detection limit was $0.005{\mu}g/mL$.

Diffusion-weighted and Dynamic Contrast-enhanced MRI of Metastatic Bone Tumors: Correlation of the Apparent Diffusion Coefficient, $K^{trans}$ and $v_e$ values (골전이암의 확산강조영상과 역동적 조영증강 자기공명영상: 겉보기 확산계수, $K^{trans}$$v_e$ 값들의 상관관계)

  • Koo, Ji Hyun;Yoon, Young Cheol;Kim, Jae Hoon
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.1
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    • pp.25-33
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    • 2014
  • Purpose : To investigate whether quantitative parameters derived from Diffusion-weighted magnetic resonance imaging (DW-MRI) correlate with those of Dynamic contrast-enhanced MRI (DCE-MRI). Materials and Methods: Thirteen patients with pathologically or clinically proven bony metastasis who had undergone MRI prior to treatment were included. The voxel size was $1.367{\times}1.367{\times}5mm$. A dominant tumor was selected and the apparent diffusion coefficient (ADC) value and DCE-MRI parameters were obtained by matching voxels. DCE-MRI data were analyzed yielding estimates of $K^{trans}$ (volume transfer constant) and $v_e$. (extravascular extracellular volume fraction). Statistical analysis of ADC, $K^{trans}$, and $v_e$ value was conducted using Pearson correlation analyses. Results: Fifteen lesions in pelvic bones were evaluated. Of these, 11 showed a statistically significant correlation (P<0.05) between ADC and $K^{trans}$. The ADC and $K^{trans}$ were inversely related in 7 lesions and positively related in 4 lesions. This did not depend on the primary cancer or site of metastasis. The ADC and $v_e$ of 9 lesions correlated significantly. Of these, 4 lesions were inversely related and 5 lesions were positively related. Conclusion: Unlike our theoretic hypothesis, there was no consistent correlation between ADC values and $K^{trans}$ or between ADC values and $v_e$ in metastatic bone tumors.