• Title/Summary/Keyword: K-6

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Oxidation of 2,6-Dimethylnaphthalene by Co-Mn-Br Based Homogeneous Catalyst (Co-Mn-Br계 균일촉매를 이용한 2,6-Dimethylnaphthalene의 산화반응)

  • Kim, Dong-Bum;Park, Seungdoo;Cha, Woonou;Roh, Hang-Duk;Kwak, Kyu Dae
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.863-870
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    • 1999
  • The catalytic performance of Co-Mn-Br system was performed in the 2,6-dimethylnaphthalene(DMN) oxidation at relatively mild reaction conditions such as $160^{\circ}C$ and $6kg/cm^2$. Experiments were conducted using a $2{\ell}$ batch reactor with varying the concentrations of catalysts. The reaction route of DMN oxidation was considered by measuring the concentration of intermediate species. As the intermediate species, 2-formyl-6-naphthoic acid, 2-methyl-6-naphthoic acid and 2-hydroxymethyl-6-methylnaphthalene are found. It was found that the yield of 2,6-naphthalene dicarboxylic acid(NDA) is largely dependent on the Co and Br concentrations. In addition, it was observed that color-b was closely related with Mn concentration in this experimental range. The burning loss of solvent could be reduced by controlling the concentration of Mn and Br. Addition of small amount of Ce and Cu compounds led to increase the NDA yields and decrease the burning amount of solvent.

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Glucose 6-Phosphate Dehydrogenase Activity of Bovine Embryos Produced in vitro (소 체외수정란의 Glucose 6-Phosphate Dehydrogenase 활성)

  • Ryoo, Z.Y.;Park, H.D.;Lee, K.K.
    • Clinical and Experimental Reproductive Medicine
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    • v.22 no.3
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    • pp.301-307
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    • 1995
  • 소 체외수정란에 있어서 pentose phosphate pathway (PPP)를 연구하기 위해서, 한개의 체외수정란으로부터 glucose 6-phosphate dehydrogenase (G6PDH)의 활성을 효소증폭방법으로 측정하였다. Glucose 6-phosphate (G6P) 기질을 처리하지 않은 2, 4, 8세포기, 상실배 및 배반포기 수정란에서의 G6PDH 활성치는 각각 $25.5{\pm}3.3$, $27.8{\pm}3.4$, $40.9{\pm}6.2$, $34.9{\pm}3.6$$52.9{\pm}2.5{\times}10^{-8}mol/embryo/h$ 을 나타내었다. 즉, 8 세포기 이후 수정란들은 2 세포기나 4 세포기보다도 높은 효소활성치를 보여주었다 (P<0.01). 그리고 G6P 기질을 첨가한 2,4,8 세포기, 상실배기 및 배반포기 수정란의 G6PDH 활성치는 각각 $32.3{\pm}3.9$, $29.4{\pm}1.8$, $51.9{\pm}4.2$, $42.6{\pm}2.7$$52.9{\pm}2.5{\times}10^{-8}mol/embryo/h$ 로서 기질 무처리구와 마찬가지로 유의성이 인정되었다 (P<0.01). 전반적으로 수정란의 발달단계에 있어서 G6P 첨가한 수정란들에 G6PDH의 효소활성치가 기질을 처리하지 수정란들의 것보다도 높은 경향을 보였다. 한편, 소 체외수정란의 G6PDH 효소활성치와 발생능과의 관계를 알아보기 위하여, 4 세포기 수정란들을 효소활성치의 정량적 수준 (low, middle, high)에 따라 3 군으로 분류한 다음 $38.5^{\circ}C$, 5% $CO_2$에서 5일간 난구세포들과 공동배양을 실시하였다. 그 결과, G6PDH 효소활성치 차이에 따른 수정란들의 체외발달율에는 유의성이 인정되지 않았다. 본 실험의 결과를 종합하여 볼 때, 소 체외수정란에 있어서 PPP 대사는 8세포기 이후부터 활발히 이루어지고 있음을 알 수 있었다.

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Quantitative investigations of titanium alloy implants (타이태늄 합금의 생체적합도에 관한 연구)

  • Han, Chong-Hyun;Heo, Seong-Joo;Ku, Young;Choi, Young-Chang;Chung, Chong-Pyong;Park, Chung-Keun
    • Journal of Periodontal and Implant Science
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    • v.28 no.3
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    • pp.401-408
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    • 1998
  • Screw shaped implants of Titanium-13Zirconium-6Niobium(newly developed), Titanium-6Zirconium-6Sn-6Niobium(newly developed) and Titanium-6Aluminum-4Vanadium were machined with square top and inserted in rabbit bone for 3 months. Biomechanical tests(removal torque) showed Titanium-13Zirconium-6Niobium and Titanium-6Zirconium-6Sn-6Niobium to be more stable in the bone bed than those of Titanium-6Aluminum-4Vanadium. Titanium-13Zirconium-6Niobium implants demonstrated a mean removal torque of 31.59Ncm while Titanium-6Aluminum-4Vanadium demonstrated a mean removal torque of 25.27Ncm and Titanium-6Zirconium-6Sn-6Niobium revealed a mean removal torque of 37.44Ncm and were statistically significance in Wilcoxon Signed Rank test(P<0.05). Histomorphometrical comparisons were performed on $10\;{\mu}m$ thick undecalcified ground sections in the light microscope and Titanium-13Zirconium-6Niobium showed more mean bone-tometal contact ratio than to other twotitanium alloys but had no statistically significant differences were found among the three materials(P>0.01).

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Synthesis of Organic Carbonates with Alkyl/aryl 4,5-dichloro-6-oxopyridazine-1(6H)-carboxylates and ROH/AlCl3 under Ambient Condition

  • Sung, Gi Hyeon;Kim, Bo Ram;Ryu, Ki Eun;Kim, Jeum-Jong;Yoon, Yong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.35 no.9
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    • pp.2758-2764
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    • 2014
  • We demonstrated the synthesis of organic carbonates using alkyl/aryl 4,5-dichloro-6-oxopyridazine-1(6H)-carboxylates and alcohol in the presence of aluminum chloride. Alkyl/aryl 4,5-dichloro-6-oxopyridazine-1(6H)-carboxylates were reacted with alcohol in the presence of $AlCl_3$ in toluene at room temperature to afford the corresponding unsymmetric and symmetric organic carbonates in good to excellent yields. These are efficient and convenient processes. Alkyl/aryl 4,5-dichloro-6-oxopyridazine-1(6H)-carboxylates are solid, stable and non-toxic $CO_2/CO_2R$(Ar) source. It is noteworthy that the reaction is carry out under an ambient and acidic conditions, the easy-to prepare and readily available starting materials and the quantitative isolation of reusable 4,5-dichloropyridazin-3(2H)-one.

Effect of [6]-Gingerol, a Pungent Ingredient of Ginger, on Osteoblast Response to Extracellular Reducing Sugar

  • Kim, Young-Ho;Nguyen, Huu Thng;Ding, Yan;Park, Sang-Heock;Choi, Eun-Mi
    • Food Science and Biotechnology
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    • v.16 no.5
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    • pp.807-811
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    • 2007
  • Diabetes is marked by high glucose levels and is associated with decreased bone mass and increased fracture rates. To determine if [6]-gingerol could influence osteoblast dysfunction induced by 2-deoxy-D-ribose (dRib), osteoblastic MC3T3-E1 cells was treated with dRib and [6]-gingerol and markers of osteoblast function and oxidized protein were examined. [6]-Gingerol ($10^{-7}\;M$) significantly increased the growth of MC3T3-E1 cells in the presence of 30 mM dRib (p<0.05). [6]-Gingerol ($10^{-7}\;M$) caused a significant elevation of alkaline phosphatase (ALP) activity, collagen content, and osteocalcin secretion in the cells. We then examined the effect of [6]-gingerol on the production of osteoprotegerin and protein carbonyl in osteoblasts. Treatment with [6]-gingerol ($10^{-9}$ and $10^{-7}\;M$) increased osteoprotegerin secretion in osteoblastic cells. Moreover, [6]-gingerol ($10^{-9}$ and $10^{-7}\;M$) decreased protein carbonyl contents of osteoblastic MC3T3-E1 cells in the presence of 30 mM dRib. Taken together, these results demonstrate that [6]-gingerol inhibits dRib-induced damage and may be useful in the treatment of diabetes related bone diseases.

An inhibitory role of NEK6 in TGFβ/Smad signaling pathway

  • Zuo, Jie;Ma, Haijie;Cai, Hao;Wu, Yanhua;Jiang, Wei;Yu, Long
    • BMB Reports
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    • v.48 no.8
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    • pp.473-478
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    • 2015
  • The NEK6 (NIMA-related kinases 6) is reported to play po-tential roles in tumorigenesis. Although it is suggested to function in several cellular pathways, the underlying mechanism in tumorigenesis is still largely unknown. In the present study, we discovered interaction of NEK6 with Smad4, a key member of transforming growth factor beta (TGFβ) pathway. Over-expression of NEK6 in hepatocellular carcinoma (HCC) cell lines suppresses TGFβ-mediated transcription activity in a kinase activity-dependent manner. In addition, NEK6 suppresses the cell growth arrest induced by TGFβ. Mechanically, NEK6 blocks nuclear translocation of Smad4, which is essential for TGFβ function. Moreover, we identified that NEK6 could be regulated by TGFβ and hypoxia. Our study sheds new light on the roles of NEK6 in canonical TGFβ/Smad pathway and tum-origenesis. [BMB Reports 2015; 48(8): 473-478]

Inhibitory effects of Capsicum annuum L. water extracts on lipoprotein lipase activity in 3T3-L1 cells

  • Baek, Jongmi;Lee, Jaesung;Kim, Kyoungkon;Kim, Taewoo;Kim, Daejung;Kim, Cheonan;Tsutomu, Kanazawa;Ochir, Sarangowa;Lee, Kooyeon;Park, Cheol Ho;Lee, Yong-Jik;Choe, Myeon
    • Nutrition Research and Practice
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    • v.7 no.2
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    • pp.96-102
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    • 2013
  • Obesity, an intractable metabolic disease, currently has no medical treatment without side effects, so studies have been actively carried out to find natural compounds that have anti-obesity activity with minimum side effects. In this study, the anti-obesity effects of water extracts of seven Capsicum annuum L. varieties being Putgochu (Pca), Oyee gochu (Oca), Kwari putgochu (Kca), Green pepper (Gca), Yellow paprika (Yca), Red paprika (Rca) and Cheongyang gochu (Cca), were examined through the evaluation of lipoprotein lipase (LPL) mRNA expression level in 3T3-L1 cells (mouse pre-adipocytes). After capsaicin elimination by chloroform defatting, freeze-dried powder of Cca was treated to 3T3-L1 cells and anti-obesity effects were examined by determining the LPL mRNA level using the RT-PCR method. Of the primary fractions, only proven fractions underwent secondary and tertiary refractionating to determine anti-obesity effects. From seven different Capsicum annuum L., there was a significant decrease of the LPL mRNA expression level of 50.9% in Cca treatment compared to the control group. A significant decrease of the LPL mRNA expression level was shown in primary fractions (Fr) 5 (36.2% decrease) and 6 (30.5% decrease) of the Cca water extracts. Due to the impurities checked by UPLC chromatography, Fr 5 and 6 were refractionated to determine the LPL mRNA expression level. Treatment of Fr 6-6 (35.8% decrease) and Fr 5-6 (35.3% decrease) showed a significant decrease in the LPL mRNA expression level. When analyzed using UPLC, major compounds of Fr 6-6 and Fr 5-6 were very similar. Subsequently, we refractionated Fr 6-6 and Fr 5-6 to isolate the major peak for structure elucidation. Treatment of Fr 5-6-1 (26.6% decrease) and Fr 6-6-1 (29.7% decrease) showed a significant decrease in the LPL mRNA expression level. Consequently, the fractions may have a possibility to ameliorate obesity through the decrease of the LPL mRNA expression level.

Analysis of Deterioration Characteristics by Filtering Processes at 6.6kV Power Cable Systems in Operation (운전 중인 6.6kV 전력 케이블 시스템의 필터링 과정에 의한 열화 특성 해석)

  • Um, Kee-Hong;Lee, Kwan-Woo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.205-211
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    • 2014
  • With a development of modern industry, demand for electric power is rapidly increasing and the capacity of power transfer is required to become bigger and bigger. At power station, the high-voltage power cable is used as the only method in order to transfer electric power. In this paper, we have analyzed the deterioration characteristics of 6.6kV power cable systems in operation. For the time duration of 2000 days, we have measured the cable in operation in order to extract the data for the deterioration characteristics. By analyzing the data by means of several steps of filtering processes, we could obtain the linear relations of insulation resistances as a function of time. Furthermore, we can verify that the progress characteristics in deterioration process of 6.6kV power cable systems follows the process of heat deterioration.

Physical and Sensory Characteristics of Korean Style Meat Products (한국형 육가공 제품류의 물리적 및 관능적 품질 특성)

  • Kim, I.S.;Jin, S.K.;Hah, K.H.;Lyou, H.J.;Park, K.H.
    • Journal of Animal Science and Technology
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    • v.47 no.1
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    • pp.49-56
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    • 2005
  • The Korean styled meat products such as grilled and/or roasted ham(Jikhwagui: J), Bulgogi ham(B), Kimbab ham(K) and sliced roasted ham(DDukgalbi: D) were obtained from different Korean meat processing companies and investigated for their salinity, saccharinity, pH, moisture and fat content, meat color and sensory evaluation. The results obtained were as follows; Percentage of saccharinity in J, B, K and D ranged 7.5 %(13) - 12.7% (J2), 5.3 0/«B2) -7.5 o/«BI), 5.2 0/«K4) - 6.6 o/«KI, K2, KS), and 6.60/«04) - 14.4o/«Dl), respectively. Percentage of salinity in J, B, K and D ranged 2.260/«13)- 2.38 0/«J4), 1.850/«B2) - 2.45 0/«B3), 1.94o/«KI) - 2.40% (K3), and 1.830/«02) - 2.19 o/«Dl), respectively. The pH value of J, B and K were ranged 6.30 - 6.44, 6.266.37 and 6.20 - 6.42, respectively, which are slightly higher than that of D(5.86 - 6.25). Content of average moisture were higher in B(61.0 %), K(59.94%) and J(59.63%) compared to the D(55.93%). In crude fat, B and D were ranged 14-21 %, which are very lower than those of K(59.94%) and J(59.63%). In meat color, $L^*$ value were above 50.0, except D2 and D3. $a^*$ value of B were slightly higher than those of other meat products. Compared to sensory evaluation, the overall acceptability of J is excellent in the range of saccharinity 12.7%, salinity 2.3 %, moisture 61 %, crude fat II - 12%, $L^*$ value 52 - 54, and $a^*$ value 12.3- 12.7. In the case of B, the overall acceptability is excellent in the range of saccharinity 6.6 - 7.5 %, salinity 1.90- 2.45 %, moisture 60 %, crude fat 15 %, $L^*$ value 56, and $a^*$ value 15. In the case of K, the overall acceptability is excellent in the range of saccharinity 6.5 %, salinity 2.4 %, moisture 61 %, crude fat 16%, $L^*$ value 53, and $a^*$ valuce 15. In the case of D, the overall acceptability is excellent in the range of saccharinity 14.0%, salinity 2.1 %, moisture 55%, crude fat 55%, $L^*$ value 50, and $a^*$ value 13.

Inhibition of the expression on MMP-2, 9 and morphological changes via human fibrosarcoma cell line by 6,6'-bieckol from marine alga Ecklonia cava

  • Zhang, Chen;Li, Yong;Shi, Xiujuan;Kim, Se-Kwon
    • BMB Reports
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    • v.43 no.1
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    • pp.62-68
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    • 2010
  • Matrix Metalloproteinases (MMPs) are a family of zinc-endopeptidases which can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. 6,6'-bieckol isolated and characterized from an edible marine brown alga Ecklonia cava (EC), according to the comprehensive spectral analysis of MS and NMR data. Here the influence of 6,6'-bieckol on expressions of MMPs was examined by zymography and western blot analysis via human fibrosarcoma cell line (HT1080). It is shown that 6,6'-bieckol significantly down regulated the expressions of MMP-2 and -9 in dose-dependent manner. The influence of 6,6'-bieckol on the cell viability and cell behavior of HT1080 cells were also investigated, our dates shown that it suppressed the migration and 3D culture in HT1080 cells. Meanwhile, we explored several signal pathways which may contribute to this process, and found the suppressing of MMPs expressions in HT1080 cells might be due to the suppression of NF-${\kappa}B$ signal pathway.