首次采用反相高效液相色谱法测定茜草根中1,3,6-trihydroxy-2-methylanthraquinone-3-O-[3-O-acetyl-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]的含量。色谱柱为Purospher star RP C18色谱柱(250mm×4.6mm,5μm),流动相...首次采用反相高效液相色谱法测定茜草根中1,3,6-trihydroxy-2-methylanthraquinone-3-O-[3-O-acetyl-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]的含量。色谱柱为Purospher star RP C18色谱柱(250mm×4.6mm,5μm),流动相为甲醇:水:四氢呋喃(65:34.7:0.3),流速为1.0mL/min,检测波长为276nm,柱温为25℃。该方法的线性范围为0.020~0.160μg,r=0.9998,平均回收率为101.5%,RSD为2.0%(n=6)。该方法测定1,3,6-trihydroxy-2-methylanthraquinone-3-O-[3-O-acetyl-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]含量灵敏、准确、重现性好。展开更多
AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma...AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.展开更多
Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean be...Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean behavior of the Ol tide. A clear seasonal variation in amplitude of the O1 tide ranging from -0.3 m/s to 2.6 m/s was observed. In most months, the northward and eastward components differed by about 7 lunar hours with the eastward component leading. Comparison of the amplitudes of the M2 and O1 tides suggests the O1 tide is quite stronger over Wuhan, China. The amplitude ratio of the O1 tide to the M2 tide is quite stronger than that the gravitational potential being 0.41. The vertical wavelength of the O1 tide differs on a monthly basis. Height profiles of the O1 tide showed obvious height variation. The O1 tide is stronger in January and July. In different month, the vertical wavelength for the O1 tide changes considerably at the same height. The year's variation trend of the northward and eastward components is very similar in both phase and amplitude.展开更多
Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures wer...Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.展开更多
Two new acetylated flavonoid diglycosides, scutellarein-5-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-6-O-acetylglucopyranoside](1), apigenin-5-O-[α-L-rhamnopyranosyl-(1→ 2)-β-D-3,6-di-O-acetylglucopyranoside] (2...Two new acetylated flavonoid diglycosides, scutellarein-5-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-6-O-acetylglucopyranoside](1), apigenin-5-O-[α-L-rhamnopyranosyl-(1→ 2)-β-D-3,6-di-O-acetylglucopyranoside] (2), were isolated from the leaves of Cephalotaxus sinensis. Their structures were determined by chemical and spectroscopic methods including HR-FAB-MS,^1H-^1H COSY, HSQC and HMBC experiments.展开更多
A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid (1) and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl...A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid (1) and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester (2), have been isolated from the aerial part of CenteUa asiatica. Their structures were elucidated by spectral methods, including 2D-NMR spectra.展开更多
文摘首次采用反相高效液相色谱法测定茜草根中1,3,6-trihydroxy-2-methylanthraquinone-3-O-[3-O-acetyl-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]的含量。色谱柱为Purospher star RP C18色谱柱(250mm×4.6mm,5μm),流动相为甲醇:水:四氢呋喃(65:34.7:0.3),流速为1.0mL/min,检测波长为276nm,柱温为25℃。该方法的线性范围为0.020~0.160μg,r=0.9998,平均回收率为101.5%,RSD为2.0%(n=6)。该方法测定1,3,6-trihydroxy-2-methylanthraquinone-3-O-[3-O-acetyl-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside]含量灵敏、准确、重现性好。
基金Supported by A 2-year grant of the Greek Ministry of Health and Welfare,No.111K/56
文摘AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.
基金Acknowledgements This research was supported by National Natural Science Foundation of China (41104095)
文摘Horizontal winds in the mesosphere (80-100 km) were measured by meteor radar in Wuhan, China (30° N, 114° E) over a 45-month interval in 2002-2005 and the data examined to investigate the monthly mean behavior of the Ol tide. A clear seasonal variation in amplitude of the O1 tide ranging from -0.3 m/s to 2.6 m/s was observed. In most months, the northward and eastward components differed by about 7 lunar hours with the eastward component leading. Comparison of the amplitudes of the M2 and O1 tides suggests the O1 tide is quite stronger over Wuhan, China. The amplitude ratio of the O1 tide to the M2 tide is quite stronger than that the gravitational potential being 0.41. The vertical wavelength of the O1 tide differs on a monthly basis. Height profiles of the O1 tide showed obvious height variation. The O1 tide is stronger in January and July. In different month, the vertical wavelength for the O1 tide changes considerably at the same height. The year's variation trend of the northward and eastward components is very similar in both phase and amplitude.
文摘Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.
文摘Two new acetylated flavonoid diglycosides, scutellarein-5-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-6-O-acetylglucopyranoside](1), apigenin-5-O-[α-L-rhamnopyranosyl-(1→ 2)-β-D-3,6-di-O-acetylglucopyranoside] (2), were isolated from the leaves of Cephalotaxus sinensis. Their structures were determined by chemical and spectroscopic methods including HR-FAB-MS,^1H-^1H COSY, HSQC and HMBC experiments.
文摘A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid (1) and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester (2), have been isolated from the aerial part of CenteUa asiatica. Their structures were elucidated by spectral methods, including 2D-NMR spectra.