排序方式: 共有33条查询结果,搜索用时 15 毫秒
1.
Paraoxonase genotype, LDL-oxidation and carotid atherosclerosis in male life-long smokers 总被引:1,自引:0,他引:1
Van Himbergen T Roest M De Waart F De Graaf J Voorbij H Van Tits L Stalenhoef A 《Free radical research》2004,38(6):553-560
Paraoxonase (PON-1) is a high-density lipoprotein (HDL) associated enzyme that hydrolyzes lipid peroxides in vitro, which may therefore protect against the onset of atherosclerosis. Heavy smokers are more exposed to oxidative stress and hence at high-risk for oxidative modification of LDL. Our hypothesis is that the anti-oxidative properties of PON-1 inhibit LDL oxidation, especially in populations exposed to high oxidative stress. We have studied the effects of PON-1 genotype and smoking to variation in oxidative status parameters and intima-media thickness (IMT), a surrogate marker of atherosclerosis. The contribution of two common polymorphisms in the PON-1 gene (Q192R and L55M) to LDL oxidizability, autoantibodies directed against oxLDL and IMT were studied in 207 male life-long smokers. Smokers were classified into average, heavy and excessive smokers based on pack years of cigarettes smoked. PON-1 genotype was not associated with autoantibodies to oxLDL, LDL oxidizability or IMT. Smoking was associated with IMT in subgroups with the high levels of LDL, but not in the population at large. The lack of association of PON-1 genotype with oxidative status parameters and IMT suggests that PON-1 is not a major inhibitor of LDL oxidation in a population of life-long smokers. 相似文献
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van Tits LJ Jacobs EM Swinkels DW Lemmers HL van der Vleuten GM de Graaf J Stalenhoef AF 《Biochemical and biophysical research communications》2006,345(1):371-376
Non-transferrin-bound iron (NTBI) is implicated in lipid peroxidation but the relation with oxidative modification of low-density lipoprotein (LDL) is not known. We assessed variables reflecting in vitro and in vivo LDL oxidation in two age- and sex-matched groups (n=23) of hereditary hemochromatosis heterozygotes (C282Y), characterized by a clear difference in mean serum NTBI (1.55+/-0.57 micromol/L vs 3.70+/-0.96 micromol/L). Plasma level of oxidized LDL (absolute and relative to plasma apolipoprotein B), and IgG and IgM antibodies to oxidized LDL, markers of in vivo LDL oxidation, did not differ between the groups with low and high serum NTBI. Mean lag-phase of in vitro LDL oxidation was also not significantly different between both study groups. Conclusion: these findings do not support the hypothesis that NTBI promotes oxidative modification of plasma LDL. 相似文献
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Through a combination of spectroscopic techniques (UV, IR, mass spectrometry and NMR) it has been possible to show that strychnozairine, an alkaloid isolated from the root bark of Strychnos variabilis, is N1-acetyl-16-R-formyl-19-oxo-20,21-didehydrostrychnane. 相似文献
5.
Goffin E da Cunha AP Ziemons E Tits M Angenot L Frederich M 《Phytochemical analysis : PCA》2003,14(6):378-380
A simple, rapid and reliable reversed-phase high-performance liquid chromatographic method for the determination of tagitinin C, an anti-plasmodial sesquiterpene lactone isolated from the aerial parts of Tithonia diversifolia, has been developed. The assay has been used to quantify tagitinin C in various extracts of the aerial parts of T. diversifolia. 相似文献
6.
LC/MS/NMR analysis of isomeric divanilloylquinic acids from the root bark of Fagara zanthoxyloides Lam 总被引:1,自引:0,他引:1
Ouattara B Angenot L Guissou P Fondu P Dubois J Frédérich M Jansen O van Heugen JC Wauters JN Tits M 《Phytochemistry》2004,65(8):1145-1151
Gradient HPLC coupled to DAD/UV, MS/MS and NMR has been applied to the rapid structure determination of three new isomeric divanilloylquinic acids from Fagara zanthoxyloides collected in Burkina Faso: 3,4-O-divanilloylquinic acid, 3,5-O-divanilloylquinic acid and 4,5-O-divanilloylquinic acid. Furthermore these new compounds named burkinabins A-C could play a useful role in sickle cell disease, as the active agents of Fagara zanthoxylo?des are said to be unidentified aromatic compounds with carboxylic acid grouping (Adesanya, S.A., Sofowora, A., 1983. Biological standardisation of Zanthoxylum roots for antisickling activity. Planta Med. 48, 27-33). 相似文献
7.
Devia B Llabres G Wouters J Dupont L Escribano-Bailon MT de Pascual-Teresa S Angenot L Tits M 《Phytochemical analysis : PCA》2002,13(2):114-119
Two new 3-deoxyanthocyanidins, 6,7,3',4'-tetrahydroxy-5-methoxyflavylium and 6,7,4'-trihydroxy-5-methoxyflavylium, and the pigment carajurin, which has been previously identified, were isolated from dried leaves of Arrabidaea chica, a creeper native to the American tropics. The structures of the components were elucidated by 1H- and 13C-NMR spectroscopy and HPLC-MS, including X-ray crystallographic analysis for carajurin. 相似文献
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Pereira CA Yariwake JH Lanças FM Wauters JN Tits M Angenot L 《Phytochemical analysis : PCA》2004,15(4):241-248
A high-performance thin layer chromatographic (HPTLC) method was developed in order to determine quantitatively the flavonoids in leaves of Passiflora alata, P. edulis, P. caerulea and P. incarnata. The content of orientin and isoorientin was determined, and the results were compared with those obtained using a quantitative HPLC-UV method. The latter employed rutin as standard and was developed to analyse flavonoid content from Passiflora leaves for the purpose of ensuring the quality of Passiflora phytomedicines. The results obtained using the two methods indicate that there are qualitative and quantitative differences in the flavonoids of the reference Passiflora species studied. The two methods were also employed to analyse commercial samples to illustrate their application in qualitative ('fingerprint') and quantitative determination, demonstrating their feasibility in the quality control of flavonoids from crude Passiflora drugs and phytomedicines. The HPLC conditions used are also suitable for the quantitative analysis of aqueous extracts (Passiflora infusions). 相似文献
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Penelle J Christen P Molgó J Tits M Brandt V Frédérich M Angenot L 《Phytochemistry》2001,58(4):619-626
Two new quaternary indole alkaloids 5',6'-dehydroguiachrysine (1) and 5',6'-dehydroguiaflavine (2) were isolated from Strychnos guianensis stem bark. Their structures were determined by analysis of spectral data. Their inhibitory effects on neuromuscular transmission are also reported and compared to that of other quaternary alkaloids. 相似文献
10.
van Lieshout AW Popa C Meyer-Wentrup F Lemmers HL Stalenhoef AF Adema GJ van Riel PL van Tits LJ Radstake TR 《Biochemical and biophysical research communications》2007,355(2):392-397
CXCL16 acts as a scavenger receptor for oxLDL in its membrane-bound form and induces migration of activated T cells in its soluble form. Due to these properties, CXCL16 has been suggested to play a role in both atherosclerosis and rheumatoid arthritis (RA). Our aim was to evaluate the contribution of soluble CXCL16 to the scavenging of oxLDL and its potential as a marker for cardiovascular disease (CVD) in patients with RA. We found that circulating CXCL16 was not correlated with plasma oxLDL or ApoB and was not related to the presence of CVD in RA patients. Moreover, CXCL16 did not bind and scavenge oxLDL in an in vitro setting. These data suggest that binding of oxLDL by soluble CXCL16 does not play a role in atherosclerosis and, although confirmation in larger studies is needed, that circulating CXCL16 is not related to the presence of CVD in patients with RA. 相似文献