AIM: To measure plasma D-dimer levels in cirrhotic patients with and without ascites, assessing the effect of ascites resolution in D-dimer concentration. METHODS: Seventy consecutive cirrhotic patients (M = 44, F = 2...AIM: To measure plasma D-dimer levels in cirrhotic patients with and without ascites, assessing the effect of ascites resolution in D-dimer concentration. METHODS: Seventy consecutive cirrhotic patients (M = 44, F = 26, mean age 65 years, SD ± 13), observed from October 2005 to March 2006 were enrolled. Circulating D-dimer levels were measured using a latex-enhanced, immunoturbidimetric test. In patients with ascites (n = 42) the test was repeated after ascites resolution. RESULTS: Ascites was present in 42 patients (group A) and absent in 28 (group B). Group A patients had more advanced liver disease. Hepatocellular carcinoma (HCC) was diagnosed in 14 patients and was more frequent in group B. Above normal range D-dimers were found in 45/70 patients. High D-dimers were more frequent in group A than in group B (P = 0.001). High D-dimers were associated with presence of HCC (P = 0.048) only in group B. After ascites resolution, obtained in all patients, mean D-dimer values decreased in those 34 patients with high basal levels (P = 0.007), returning to normal in 17. CONCLUSION: In patients with liver cirrhosis, ascites and HCC are the main factors associated with increased fibrinolytic activity.展开更多
Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C...Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C,H,and J.Eight compounds(1,4,10,12,13,and 19-21) were unambiguously confirmed by the single-crystal X-ray diffraction analyses,and the others were elucidated based on IR,UV,HRESIMS,1 D and 2 D NMR experiments,and comparison of the experimental and calculated ECD data.Structurally,all of them were [4+2] Diels-Alder adducts of two monomeric guaianolides.The isolates were evaluated for their cytotoxicity against three human hepatoma cell lines,and 19 compounds demonstrated cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines.Especially,compounds 1,12,14,and 15 exhibited cytotoxicity with IC50 values of 4.4,3.8,7.6,and 6.7 μmol/L(HepG2),9.6,4.6,6.6,and 6.0 μmol/L(SMMC-7721),and 7.6,4.5,6.9,and 5.6 μmol/L(Huh7),respectively.Notably,compound 12 showed the most promising activity against three human hepatoma cell lines and dose-dependently inhibited cell migration and invasion,induced G2/M cell cycle arrest and cell apoptosis in HepG2 cells,down-regulated the expression of BCL-2 and PARP-1,and activated PARP-1 to up-regulate the expression of cleaved-PARP-1.展开更多
Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results ...Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.展开更多
In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl gro...In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.展开更多
Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus Sieb.Compound 1 possesses an unprecedented 3/5/7/5/5/6/...Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus Sieb.Compound 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2 exhibits a 3/5/6/6/5/6/5/3 fused octacyclic scaffold.Their structures were determined through a combination of spectroscopic analyses and X-ray crystallography.Compounds 1,2,and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2 cell model.In addition,compounds 1,2,and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—22 and 25 inhibited the NO production induced by lipopolysaccharide in RAW 264.7 macrophages with IC50 values of 7.89±0.44,6.25±0.46,2.98±0.29,10.77±0.60,and 3.60±0.28μmol/L.展开更多
To elucidate the synergistic effect of dual-atom catalysts(DACs)at the microscopic level,we propose and construct a prototype heteronuclear system,CuNi/TiO_(2),in which the two elements of a pair have significantly di...To elucidate the synergistic effect of dual-atom catalysts(DACs)at the microscopic level,we propose and construct a prototype heteronuclear system,CuNi/TiO_(2),in which the two elements of a pair have significantly different d electron-donating abilities,as a piece in the puzzle.Using density functional theory calculations,we investigate charge-dependent configurations of Cu-Ni dimers anchored on TiO_(2)by the mixing of individual constituent atoms.The d electron-donating ability determines deposition sequence and position of transition metal atoms on oxides,establishing dimer pattern and metal-support interactions.The interaction between Cu and Ni,beyond the coordination environment,predominately contributes to the synergistic effect.A complex adsorption-reduction behavior of H species on CuNi/TiO_(2)is observed.The reaction mechanism and catalytic activity of CuNi/TiO_(2)for hydrogen production are explored.At room temperature and high H coverages,CuNi/TiO_(2)shows better performance and efficiency than Ni1/TiO_(2).Our findings provide a new understanding of the synergistic effect on structure-activity relationships of supported dimers,which would be beneficial in the future design of various DACs or even atomically dispersed metal catalysts.展开更多
文摘AIM: To measure plasma D-dimer levels in cirrhotic patients with and without ascites, assessing the effect of ascites resolution in D-dimer concentration. METHODS: Seventy consecutive cirrhotic patients (M = 44, F = 26, mean age 65 years, SD ± 13), observed from October 2005 to March 2006 were enrolled. Circulating D-dimer levels were measured using a latex-enhanced, immunoturbidimetric test. In patients with ascites (n = 42) the test was repeated after ascites resolution. RESULTS: Ascites was present in 42 patients (group A) and absent in 28 (group B). Group A patients had more advanced liver disease. Hepatocellular carcinoma (HCC) was diagnosed in 14 patients and was more frequent in group B. Above normal range D-dimers were found in 45/70 patients. High D-dimers were more frequent in group A than in group B (P = 0.001). High D-dimers were associated with presence of HCC (P = 0.048) only in group B. After ascites resolution, obtained in all patients, mean D-dimer values decreased in those 34 patients with high basal levels (P = 0.007), returning to normal in 17. CONCLUSION: In patients with liver cirrhosis, ascites and HCC are the main factors associated with increased fibrinolytic activity.
基金supported by the Yunnan Wanren Project (YNWRKJLJ-2019-002)the Program of Yunling Scholarship (Ji-Jun, Chen)the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province (Changan, Geng)。
文摘Leading by cytotoxicity against HepG2 cells,bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers,artematrolides A-R and lavandiolides A,B,C,H,and J.Eight compounds(1,4,10,12,13,and 19-21) were unambiguously confirmed by the single-crystal X-ray diffraction analyses,and the others were elucidated based on IR,UV,HRESIMS,1 D and 2 D NMR experiments,and comparison of the experimental and calculated ECD data.Structurally,all of them were [4+2] Diels-Alder adducts of two monomeric guaianolides.The isolates were evaluated for their cytotoxicity against three human hepatoma cell lines,and 19 compounds demonstrated cytotoxicity against HepG2,SMMC-7721,and Huh7 cell lines.Especially,compounds 1,12,14,and 15 exhibited cytotoxicity with IC50 values of 4.4,3.8,7.6,and 6.7 μmol/L(HepG2),9.6,4.6,6.6,and 6.0 μmol/L(SMMC-7721),and 7.6,4.5,6.9,and 5.6 μmol/L(Huh7),respectively.Notably,compound 12 showed the most promising activity against three human hepatoma cell lines and dose-dependently inhibited cell migration and invasion,induced G2/M cell cycle arrest and cell apoptosis in HepG2 cells,down-regulated the expression of BCL-2 and PARP-1,and activated PARP-1 to up-regulate the expression of cleaved-PARP-1.
基金supported by the Natural Science Foundation of Jiangsu Province (No. BK2007204)the Natural Science Foundation of Jiangsu Province Educational Committee (No. 07KJD140208).
文摘Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.
基金The authors gratefully acknowledge the financial support of the Natural Science Foundation of China,China(Grant No.21975082 and 21736003)the Guangdong Basic and Applied Basic Research Foundation(Grant Number:2019A1515011472 and 2022A1515011341)the Science and Technology Program of Guangzhou(Grant Number:202102080479).
文摘In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.
基金supported by the National Natural Science Foundation of China(Nos.22177044 and 22077058)The computational resources of this work were supported by the Supercomputing Center of Lanzhou University(China).
文摘Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus Sieb.Compound 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2 exhibits a 3/5/6/6/5/6/5/3 fused octacyclic scaffold.Their structures were determined through a combination of spectroscopic analyses and X-ray crystallography.Compounds 1,2,and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2 cell model.In addition,compounds 1,2,and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—22 and 25 inhibited the NO production induced by lipopolysaccharide in RAW 264.7 macrophages with IC50 values of 7.89±0.44,6.25±0.46,2.98±0.29,10.77±0.60,and 3.60±0.28μmol/L.
基金the National Natural Science Foundation of China(No.52272199).
文摘To elucidate the synergistic effect of dual-atom catalysts(DACs)at the microscopic level,we propose and construct a prototype heteronuclear system,CuNi/TiO_(2),in which the two elements of a pair have significantly different d electron-donating abilities,as a piece in the puzzle.Using density functional theory calculations,we investigate charge-dependent configurations of Cu-Ni dimers anchored on TiO_(2)by the mixing of individual constituent atoms.The d electron-donating ability determines deposition sequence and position of transition metal atoms on oxides,establishing dimer pattern and metal-support interactions.The interaction between Cu and Ni,beyond the coordination environment,predominately contributes to the synergistic effect.A complex adsorption-reduction behavior of H species on CuNi/TiO_(2)is observed.The reaction mechanism and catalytic activity of CuNi/TiO_(2)for hydrogen production are explored.At room temperature and high H coverages,CuNi/TiO_(2)shows better performance and efficiency than Ni1/TiO_(2).Our findings provide a new understanding of the synergistic effect on structure-activity relationships of supported dimers,which would be beneficial in the future design of various DACs or even atomically dispersed metal catalysts.
