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941.
Thuan ND Ha do T Thuong PT Na MK Lee JP Lee JH Seo HW Min BS Kim JC Bae K 《Archives of pharmacal research》2007,30(9):1062-1066
A phytochemical study on Picria tel-ferae resulted in the isolation of a phenylpropanoid glycoside (1), which was reported for the first time from this plant. The structure of compound 1 was identified as 1-O-3,4-(dihydroxyphenyl)- ethyl-beta-D- apiofuranosyl- (1-->4)-alpha-L-rharmnopyranosyl- (1-->3)-4-O-caffeoyl- beta-D-glucopyranoside on the basis of spectroscopic analyses. In addition, it was found that 1 exhibited a remarkable inhibitory effect on lipid peroxidation initiated by either a free radical [AAPH; 2,2'-azobis-(2-amidinopropane)dihydrochloride] or generated hydroxyl radical (Fe2+/ascorbate). These findings, together with those of previous studies, suggest that P. tel-ferae possesses abundant phenylpropanoid glycosides, and the plant might be used beneficially in the treatment of oxidative stress-related human diseases. 相似文献
942.
Chen QC Lee J Jin W Youn U Kim H Lee IS Zhang X Song K Seong Y Bae K 《Archives of pharmacal research》2007,30(5):565-569
Cytotoxic bioassay-guided fractionation of methanol extract of Angelicae Sinensis Radix led to the isolation of a new dimeric Z-ligustilide, named neodiligustilide (1), together with three known compounds, Z-ligustilide (2), 11(S),16(R)-dihydroxy-octadeca-9Z, 17-dien-12,14-diyn-1-yl acetate (3), and 3(R),8(S)-falcarindiol (4). Among them, 2 showed the strongest cytotoxicity against L1210 and K562 cell lines with IC50 values of 2.27 +/- 0.10 and 4.78 +/- 0.18 microM, respectively, while 1 showed moderate cytotoxicity with IC50 values of 5.45 +/- 0.19 and 9.87 +/- 0.14 microM. Two polyacetylenes, 3 and 4, showed cytotoxicity only against L1210 cell line with IC50 values of 2.60 +/- 0.90 and 2.87 +/- 0.49 microM, respectively. 相似文献
943.
Plant phenolics as prolyl endopeptidase inhibitors 总被引:1,自引:0,他引:1
Lee SH Jun M Choi JY Yang EJ Hur JM Bae K Seong YH Huh TL Song KS 《Archives of pharmacal research》2007,30(7):827-833
Prolyl endopeptidase (PEP, EC 3.4.21.26), a serine protease, is widely distributed in various organs, particularly in the brains of Alzheimer's disease patients. The expression of PEP in Alzheimer's patients has been found to be significantly higher than that of the normal person, suggesting that a specific PEP inhibitor can be a good candidate for an anti-amnestic drug. In the current study, thirty-nine plant phenolics were investigated to determine their roles as prolyl endopeptidase (PEP) inhibitors. Nineteen compounds such as 1,2,3-trigalloyl glucopyranoside, 1,2,6-trigalloyl glucopyranoside, 1,2,3,4,6-pentagalloyl gluco-pyranoside, 1,2,6-trigalloyl alloside, 1,3,6-trigalloyl alloside, 1,2,3,6-tetragalloyl alloside, acetonyl geraniin, corilagin, elaeocarpusin, euphorscopin, geraniin, helioscopin B, helioscopinin A, helioscopinin B, jolkinin, macranganin, rugosin E, supinanin, and teracatain exhibited strong inhibition against PEP (IC50 26.7 - 443.7 x 10(-9) M). Rugosin E (IC50 26.7 x 10(-9) M) showed the most effective inhibition followed by 1,2,6-trigalloyl glucopyranoside (IC5031.4 x 10(-9) M) and macranganin (IC5042.6 x 10(-9) M). No significant structure-activity relationship was found; however, at least, three pyrogallol groups seem to be a minimal requirement for stronger activity against PEP All 19 active compounds inhibited PEP in a non-competitive mode with a substrate in Dixon plots. They did not show significant effects against other serine proteases such as trypsin, chymotrypsin and elastase, indicating that they were relatively specific PEP inhibitors. 相似文献
944.
945.
Zisun Kim Min Joo Kim Jung Hoon Kim So Young Jin Yong Bae Kim Daekwan Seo Dongho Choi Kyung Yul Hur Jae Joon Kim Min Hyuk Lee Chul Moon 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2009,11(3):215-221
Background:
Post-operative pancreatic fistula (POPF) is one of the most fearful complications which may occur after pancreaticoduodenectomy (PD). The methods used to predict POPF pre-operatively have not been studied in great detail. We analyzed correlation between various parameters related to PD including pre-operative magnetic resonance imaging (MRI) signal intensity (SI), pathology of pancreatic fibrosis and occurrence rates of POPF, and verified that MRI SI results could be the determining values for pre-operative prediction of POPF.Methods:
From January 2005 to August 2006, we retrospectively examined 43 cases of PDs by reviewing abdominal MRI findings, degree of fibrosis of remnant pancreatic stump, and other surgery-related parameters.Results:
POPF encountered in PD were 11 cases (25.6%). Operation time and degree of fibrosis of remnant pancreatic cut surface were related to POPF (P= 0.030, P= 0.010). The pancreas–liver SI ratio (PLSI) between fistula group and no fistula group was −0.0009 ± 0.2 and −0.1297 ± 0.2, respectively (P= 0.0004). The pancreas–spleen SI ratio (PSSI) in each group was 0.423 ± 0.25 and 0.288 ± 0.32, respectively (P= 0.014). Using quantitative analysis, the SI ratios were 1.27 and 0.66 in each group (P= 0.013).Conclusions:
When analyzing the results of POPF in 43 patients who underwent PD, PLSI, PSSI and qualitative analysis, fistula group differed significantly from no fistula group. Using these results, it will be helpful for us to predict the occurrence of POPF pre-operatively using MRI in PD patients. 相似文献946.
947.
Jeong Ha Park Yoon-Kyoung Sung Sang-Cheol Bae Soon-Young Song Heong Seok Seo Jae-Bum Jun 《Rheumatology international》2009,29(9):1081-1086
Although digital ulceration frequently occurs in patients with systemic sclerosis, there have been few reports on macrovascular
involvement. Macrovascular disease in systemic sclerosis has recently been described. We retrospectively reviewed the medical
records and brachial angiographic findings of 19 systemic sclerosis patients, who exhibited Raynaud’s phenomenon and digital
ulceration. We found that ulnar artery involvement is frequent in systemic sclerosis, although the precise mechanism is not
known. There was no significant difference in risk factors of macrovascular disease between ulnar artery-involved patients
and not-involved subjects. Thirteen patients underwent surgical intervention; five of the 13 patients had vascular graft performed
due to ulnar artery involvement. We suggest that angiographic screening and early surgical intervention such as revascularization
should be considered in patients with systemic sclerosis who manifest a severe form of Raynaud’s phenomenon and/or digital
ulceration and especially in patients with diffuse sclerosis. 相似文献
948.
949.
950.
Park EJ Bae E Yi J Kim Y Choi K Lee SH Yoon J Lee BC Park K 《Environmental toxicology and pharmacology》2010,30(2):162-168
Toxicity of nanoparticles depends on many factors including size, shape, chemical composition, surface area, surface charge, and others. In this study, we compared the toxicity of different sized-silver nanoparticles (AgNPs) which are being widely used in consumer products due to its unique antimicrobial activity. When mice were treated with AgNPs 1mg/kg for 14 days by oral administration, small-sized AgNPs (22nm, 42nm, and 71nm) were distributed to the organs including brain, lung, liver, kidney, and testis while large-sized AgNPs (323nm) were not detected in those tissues. The levels of TGF-β in serum were also significantly increased in the treated group of small-sized AgNPs but not in large-sized AgNPs. In addition, B cell distribution was increased in small-sized AgNPs but not in large-sized-AgNPs by the phenotype analysis. However, body weight or in the ratio of organ/body weight were not different between the control group and all the AgNPs-treated groups. The repeated-dose toxicity of AgNPs (42nm) was also investigated in mice by oral administration for 28 days. By the administration of AgNPs (0.25mg/kg, 0.50mg/kg, 1.00mg/kg), adverse impacts on liver and kidney were observed in a high dose-treated group (1.00mg/kg), when determined by blood chemistry and histipathological analysis. Cytokines including IL-1, IL-6, IL-4, IL-10, IL-12, and TGF-β were also increased in a dose-dependent manner by repeated oral administration. In addition, B cell distribution in lymphocyte and IgE production were increased. Based on these results, it is suggested that repeated oral administration of nano-sized AgNPs may cause organ toxicity and inflammatory responses in mice. 相似文献