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211.
Jeong YK Yang WS Kim KH Chung KT Joo WH Kim JH Kim DE Park JU 《Biotechnology letters》2004,26(5):393-397
A fibrinolytic enzyme, myulchikinase, from a Korean seasoning ingredient, myul-chi-jeot-gal, has been purified to electrophoretic homogeneity. The molecular mass of the myulchikinase was estimated to about 28 kDa by SDS-PAGE and gel filtration. Amino acid sequence of the NH2-terminal of myulchikinase showed significant homology with other fibrinolytic enzymes including trypsin from starfish, katsuwokinase, and rat pancreatic elastase II. The purified myulchikinase hydrolyzed various synthetic substrates with different substrate specificity and cytotoxic to the tumor cell lines. 相似文献
212.
The potential role of green tea polyphenol (GtPP) in preserving the human saphenous vein was investigated under physiological conditions. The vein segments were incubated for 1, 3, 5, 7 and 14 days, either after 4h of treatment with 1.0mg/ml GtPP or in the presence of GtPP at the same concentration. After incubation, the endothelial cell viability, endothelial nitric oxide synthase (eNOS) expression and the vein histology were evaluated. When the veins were not treated with GtPP, the viability of the endothelial cells was significantly reduced with the progress in the culture time, and none of the cells expressed eNOS after 5 days. Furthermore, severe histological changes and structural damage were observed in the non-treated veins. In contrast, incubating the veins after 4h of GtPP treatment significantly prevented these phenomena. The cellular viability of the GtPP-treated vein was approximately 64% after 7 days, and eNOS expression was maintained up to 40%, compared to that of the fresh vein. The histological observations showed that the vasculature was quite similar to that of the fresh vein. When incubated with GtPP, the vein could also be preserved for 1 week under physiological conditions retaining both its cellular viability (61%) and eNOS expression level (45%) and maintaining its venous structure without any morphological changes. These results demonstrate that GtPP treatment may be a useful method for preserving the HSV. 相似文献
213.
Ring-shaped architecture of RecR: implications for its role in homologous recombinational DNA repair
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RecR, together with RecF and RecO, facilitates RecA loading in the RecF pathway of homologous recombinational DNA repair in procaryotes. The human Rad52 protein is a functional counterpart of RecFOR. We present here the crystal structure of RecR from Deinococcus radiodurans (DR RecR). A monomer of DR RecR has a two-domain structure: the N-terminal domain with a helix-hairpin-helix (HhH) motif and the C-terminal domain with a Cys4 zinc-finger motif, a Toprim domain and a Walker B motif. Four such monomers form a ring-shaped tetramer of 222 symmetry with a central hole of 30-35 angstroms diameter. In the crystal, two tetramers are concatenated, implying that the RecR tetramer is capable of opening and closing. We also show that DR RecR binds to both dsDNA and ssDNA, and that its HhH motif is essential for DNA binding. 相似文献
214.
Lee WS Lee DW Baek YI An S An SJ Cho KH Choi YK Kim HC Park HY Bae KH Jeong TS 《Bioorganic & medicinal chemistry letters》2004,14(12):3109-3112
The sesquineolignan, saucerneol B (1), and dineolignans, manassantin A (2), and manassantin B (3), were isolated from the methanol extracts of Saururus chinensis root and elucidated by their spectroscopic data analysis. Compounds 1-3 inhibited hACAT-1 and hACAT-2 with IC(50) values of 43.0 and 124.0 microM for 1, of 39.0 and 8.0 microM for 2, of 82.0 microM and only 32% inhibition at 1mM for 3, respectively. The EtOAc-soluble fraction, which contained compounds 1-3, of methanol extracts of S. chinensis exhibited strong cholesterol-lowering effect in high cholesterol-fed mice. 相似文献
215.
Park HG Choi JY Choi SH Park MK Lee J Suh YG Cho H Oh U Kim HD Joo YH Kim SY Park YH Jeong YS Choi JK Kim JK Jew SS 《Bioorganic & medicinal chemistry letters》2004,14(7):1693-1696
A series of N-4-methansulfonamidobenzyl-N'-2-substituted-4-tert-butylbenzyl thioureas were prepared for the study of their agonistic/antagonistic activities to the vanilloid receptor in rat DRG neurons. Their structure-activity relationship reveals that there is a space for another hydrophobic binding interaction around 2-position in 4-tert-butylbenzyl region. Among the prepared derivatives, 6n show the highest antagonistic activity against the vanilloid receptor (IC(50)=15 nM). 相似文献
216.
Simple aromatic compounds containing propenone moiety show considerable dual COX/5-LOX inhibitory activities 总被引:5,自引:0,他引:5
Jahng Y Zhao LX Moon YS Basnet A Kim EK Chang HW Ju HK Jeong TC Lee ES 《Bioorganic & medicinal chemistry letters》2004,14(10):2559-2562
For the development of safer anti-inflammatory agents, simple aromatic compounds containing propenone moiety were prepared and evaluated for their dual COX/5-LOX inhibitory activities. Among the 17 prepared compounds, most of the compounds exhibited considerable COX/5-LOX inhibitory activities. Especially compound C(15) showed the most significant dual COX/5-LOX inhibitory activity. 相似文献
217.
Park HG Choi JY Choi SH Park MK Lee J Suh YG Cho H Oh U Lee J Kang SU Lee J Kim HD Park YH Su Jeong Y Kyu Choi J Jew SS 《Bioorganic & medicinal chemistry letters》2004,14(3):787-791
A series of N-4-substituted-benzyl-N'-tert-butylbenzyl thioureas were prepared for the study of their agonistic/antagonistic activities to the vanilloid receptor in rat DRG neurons. Their structure-activity relationship reveals that not only the two oxygens and amide hydrogen of sulfonamido group, but also the optimal size of methyl in methanesulfonamido group play an integral role for the antagonistic activity on vanilloid receptor. 相似文献
218.
Jeong LS Kim MJ Kim HO Gao ZG Kim SK Jacobson KA Chun MW 《Bioorganic & medicinal chemistry letters》2004,14(19):4851-4854
On the basis of high binding affinity at the A(3) adenosine receptor of 3'-aminoadenosine derivatives with hydrogen bonding donor ability, novel 3'-ureidoadenosine analogues were synthesized from 1,2:5,6-di-O-isopropylidene-d-glucose in order to lead to stronger hydrogen bonding than the corresponding 3'-aminoadenosine derivatives. However, the synthesized 3'-ureidoadenosine analogues were totally devoid of binding affinity, because 3'-urea moiety caused steric and electrostatic repulsions at the binding site of the A(3) adenosine receptor, leading to conformational distortion. 相似文献
219.
Oh M Im I Lee YJ Kim YH Yoon JH Park HG Higashiyama S Kim YC Park WJ 《Bioorganic & medicinal chemistry letters》2004,14(24):6071-6074
We describe a series of potent and selective inhibitors of ADAM12 that were discovered using computational screening of a focused virtual library. The initial structure-based virtual screening selected 64 compounds from a 3D database of 67,062 molecules. Being evaluated by a cell-based ADAM12 activity assay, compounds 5, 11, 14, 16 were further identified as the potent and selective inhibitors of ADAM12 with low nanomolar IC50 values. The mechanism underlying the potency and selectivity of a representative compound, 5, was investigated through molecular docking studies. 相似文献
220.
BACKGROUND: It has previously been demonstrated that high levels of gene expression in skeletal muscles can be achieved after direct in vivo electrotransfer of naked plasmid DNA. The purpose of this study is to examine the potential of in vivo electroporation of plasmid DNA encoding human IL-1Ra for the prevention of murine collagen-induced arthritis (CIA). METHODS: DBA/1 mice were injected in gastrocnemius muscles with plasmid DNA followed by in vivo electroporation. To uncover the optimum conditions of gene transfer, various electric field strengths and different amounts of plasmid DNA were applied. Calf muscles around the injected areas were investigated with histological methods for damage to muscle tissue. The levels of human IL-1Ra expression in the injected area and also in the serum were determined with ELISA for human IL-1Ra. Based on these data, the effects of electrotransfer of plasmid DNA were tested using the murine CIA model. DBA/1 mice were immunized with bovine collagen type II at the base of the tail. On day 21, mice were given a booster injection with the same antigen. Mice were divided into two groups on day 26. One group of mice received plasmid containing the IL-1Ra cDNA sequence, while control mice were given plasmid lacking the IL-1Ra coding sequence. The incidence of arthritis was evaluated by macroscopic analysis, histological analysis, and the levels of inflammatory cytokines. RESULTS: IL-1Ra expression increased as a function of the electrical field strength and the amount of DNA. 200 V/cm (eight pulses; 20 ms per pulse; 1 Hz) and 15 microg of plasmid DNA per mouse were found to be optimum for gene transfer. After in vivo electroporation, gene expression in both muscle and serum increased gradually, reaching a peak value on day 10. Significant levels of human IL-1Ra expression were maintained for 20 days. Macroscopic analysis showed that the onset of CIA was significantly inhibited by direct electrotransfer of plasmid DNA encoding human IL-1Ra. Histological analysis of knee joints showed that the incidence of arthritis in knee joints was also prevented. The levels of mouse IL-1beta and IL-12 in paws were significantly lower in the group treated with IL-1Ra than those in the control group. CONCLUSIONS: These results demonstrate that direct electrotransfer of plasmid containing the human IL-1Ra cDNA sequence to skeletal muscle can reduce the incidence of CIA in mice. 相似文献