AIM: To study the viscoelastic properties of human hepatocytes and hepatocellular carcinoma (HCC) cells under cytoskeletal perturbation, and to further to study the viscoelastic properties and the adhesive properties ...AIM: To study the viscoelastic properties of human hepatocytes and hepatocellular carcinoma (HCC) cells under cytoskeletal perturbation, and to further to study the viscoelastic properties and the adhesive properties of mouse hepatoma cells (HTC) in different cell cycle. METHODS: Micropipette aspiration technique was adopted to measure viscoelastic coefficients and adhesion force to collagen coated surface of the cells. Three kinds of cytoskeleton perturbing agents, colchicines (Col), cytochalasin D (CD) and vinblastine (VBL), were used to treat HCC cells and hepatocytes and the effects of these treatment on cell viscoelastic coefficients were investigated. The experimental results were analyzed with a three-element standard linear solid. Further, the viscoelastic properties of HTC cells and the adhesion force of different cycle HTC cells were also investigated. The synchronous G(1) and S phase cells were achieved through thymine-2-desoryriboside and colchicines sequential blockage method and thymine-2-desoryriboside blockage method respectively. RESULTS: The elastic coefficients, but not viscous coefficient of HCC cells (K(1)=103.6+/-12.6N.m(-2), K(2)=42.5 +/ 10.4N.m(-2), mu=4.5 +/- 1.9Pa.s), were significantly higher than the corresponding value for hepatocytes (K(1)=87.5 +/- 12.1N.m(-2), K(2)=33.3+/-10.3N.m(-2), mu=5.9+/-3.0Pa.s, P【0.01). Upon treatment with CD, the viscoelastic coefficients of both hepatocytes and HCC cells decreased consistently, with magnitudes for the decrease in elastic coefficients of HCC cells (K(1): 68.7 N.m(-2) to 81.7N.m(-2), 66.3% to 78.9%; K(2): 34.5N.m(-2) to 37.1N.m(-2), 81.2% to 87.3%, P【0.001) larger than those for normal hepatocytes (K(1): 42.6N.m(-2) to 49.8N.m(-2), 48.7% to 56.9%; K(2): 17.2N.m(-2) to 20.4N.m(-2), 51.7% to 61.3%, P【0.001). There was a little decrease in the viscous coefficient of HCC cells (2.0 to 3.4Pa.s, 44.4 to 75.6%, P【0.001) than that for hepatocytes (3.0 to 3.9Pa.s, 50.8 to 66.1% P【0.001). Upon treatment with Col and VBL, the elastic coe展开更多
By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were...By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were studied with fluorescence probe technique and confocal laser scanning microscopy. There were a lot of actin filaments （AFs） impenetrate the cell wall, but the AFs with red fluorescence were absent when the cells were treated with cytochalasin D before fixation; the same result was obtained when the cells were treated with unlabeled phalloidin. These results indicate the presence of Factin in the intercellular channels and that it is related to the plasmodesmata and intercellular trafficking of macromolecules.展开更多
AIM: To study the chemical constituents of the solid culture of the endophyte Phomopsis sp. IFB-E060 in Vatica mangachapoi. METHOD: Isolation and purification were performed through silica gel column chromatography, g...AIM: To study the chemical constituents of the solid culture of the endophyte Phomopsis sp. IFB-E060 in Vatica mangachapoi. METHOD: Isolation and purification were performed through silica gel column chromatography, gel filtration over Sephadex LH-20, ODS column chromatography, and HPLC. Structures of the isolated compounds were elucidated by a combination of spectroscopic analyses(UV, CD, IR, MS, 1D, and 2D NMR). The cytotoxicity of the isolates was evaluated in vitro by the MTT method against the human hepatocarcinoma cell line SMMC-7721. RESULTS: Five compounds were isolated from the solid culture of the endophyte Phomopsis sp. IFB-E060 and their structures were identified as 18-methoxy cytochalasin J(1), cytochalasin H(2),(22E, 24S)-cerevisterol(3), ergosterol(4), and nicotinic acid(5). Compound 1 had an inhibition rate of 24.4% at 10 μg·mL-1 and 2 had an IC50 value of 15.0 μg·mL-1, while a positive control 5-fluorouracil had an inhibition rate of 28.7% at 10 μg·mL-1. CONCLUSION: 18-Methoxy cytochalasin J(1), produced by endophytic Phomopsis sp. IFB-E060, is a new cytochalasin with weak cytotoxicity to the human hepatocarcinoma cell line SMMC-7721.展开更多
A new ceramide, (2S,3S,4R, 10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1, 3,4-triol (1), together with twelve known compounds, cerebroside A, cerebroside B, cerebroside D, cytochalasin D, epoxyc...A new ceramide, (2S,3S,4R, 10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1, 3,4-triol (1), together with twelve known compounds, cerebroside A, cerebroside B, cerebroside D, cytochalasin D, epoxycytochalasin D, cytochalasin C, loganin, cerevisterol, ergosta-7,22-dien-3beta, 5alpha, 6alpha-triol, ergosta-4,6,8(14),22-tetraen-3-one, ergosterol peroxide and ergosta-5,7,22-trien-3-ol, was isolated from ethyl acetate fraction of Engleromyces goetzei P. Henn. The structure of new ceramide (1) was elucidated by spectral data and chemical method, especially by 2D-NMR techniques. All of the compounds except cytochalasin D were first obtained from this fungus.展开更多
基金the National Science Foundation of China,No.39370198
文摘AIM: To study the viscoelastic properties of human hepatocytes and hepatocellular carcinoma (HCC) cells under cytoskeletal perturbation, and to further to study the viscoelastic properties and the adhesive properties of mouse hepatoma cells (HTC) in different cell cycle. METHODS: Micropipette aspiration technique was adopted to measure viscoelastic coefficients and adhesion force to collagen coated surface of the cells. Three kinds of cytoskeleton perturbing agents, colchicines (Col), cytochalasin D (CD) and vinblastine (VBL), were used to treat HCC cells and hepatocytes and the effects of these treatment on cell viscoelastic coefficients were investigated. The experimental results were analyzed with a three-element standard linear solid. Further, the viscoelastic properties of HTC cells and the adhesion force of different cycle HTC cells were also investigated. The synchronous G(1) and S phase cells were achieved through thymine-2-desoryriboside and colchicines sequential blockage method and thymine-2-desoryriboside blockage method respectively. RESULTS: The elastic coefficients, but not viscous coefficient of HCC cells (K(1)=103.6+/-12.6N.m(-2), K(2)=42.5 +/ 10.4N.m(-2), mu=4.5 +/- 1.9Pa.s), were significantly higher than the corresponding value for hepatocytes (K(1)=87.5 +/- 12.1N.m(-2), K(2)=33.3+/-10.3N.m(-2), mu=5.9+/-3.0Pa.s, P【0.01). Upon treatment with CD, the viscoelastic coefficients of both hepatocytes and HCC cells decreased consistently, with magnitudes for the decrease in elastic coefficients of HCC cells (K(1): 68.7 N.m(-2) to 81.7N.m(-2), 66.3% to 78.9%; K(2): 34.5N.m(-2) to 37.1N.m(-2), 81.2% to 87.3%, P【0.001) larger than those for normal hepatocytes (K(1): 42.6N.m(-2) to 49.8N.m(-2), 48.7% to 56.9%; K(2): 17.2N.m(-2) to 20.4N.m(-2), 51.7% to 61.3%, P【0.001). There was a little decrease in the viscous coefficient of HCC cells (2.0 to 3.4Pa.s, 44.4 to 75.6%, P【0.001) than that for hepatocytes (3.0 to 3.9Pa.s, 50.8 to 66.1% P【0.001). Upon treatment with Col and VBL, the elastic coe
文摘By means of paraformaldehyde fixation, Triton X100 extraction and TRITCphalloidin staining, the presence and distribution patterns of Factin in the outer epidermal cells of the garlic （Allium sativum L.） sheath were studied with fluorescence probe technique and confocal laser scanning microscopy. There were a lot of actin filaments （AFs） impenetrate the cell wall, but the AFs with red fluorescence were absent when the cells were treated with cytochalasin D before fixation; the same result was obtained when the cells were treated with unlabeled phalloidin. These results indicate the presence of Factin in the intercellular channels and that it is related to the plasmodesmata and intercellular trafficking of macromolecules.
基金supported by the Natural Science Foundation of China(Nos.81121062,30701045,21132004&21072092)the Natural Science Foundation of Jiangsu Province(No.BK2009010)the Social Development Project of Yangzhou(No.YZ2011097)
文摘AIM: To study the chemical constituents of the solid culture of the endophyte Phomopsis sp. IFB-E060 in Vatica mangachapoi. METHOD: Isolation and purification were performed through silica gel column chromatography, gel filtration over Sephadex LH-20, ODS column chromatography, and HPLC. Structures of the isolated compounds were elucidated by a combination of spectroscopic analyses(UV, CD, IR, MS, 1D, and 2D NMR). The cytotoxicity of the isolates was evaluated in vitro by the MTT method against the human hepatocarcinoma cell line SMMC-7721. RESULTS: Five compounds were isolated from the solid culture of the endophyte Phomopsis sp. IFB-E060 and their structures were identified as 18-methoxy cytochalasin J(1), cytochalasin H(2),(22E, 24S)-cerevisterol(3), ergosterol(4), and nicotinic acid(5). Compound 1 had an inhibition rate of 24.4% at 10 μg·mL-1 and 2 had an IC50 value of 15.0 μg·mL-1, while a positive control 5-fluorouracil had an inhibition rate of 28.7% at 10 μg·mL-1. CONCLUSION: 18-Methoxy cytochalasin J(1), produced by endophytic Phomopsis sp. IFB-E060, is a new cytochalasin with weak cytotoxicity to the human hepatocarcinoma cell line SMMC-7721.
文摘A new ceramide, (2S,3S,4R, 10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1, 3,4-triol (1), together with twelve known compounds, cerebroside A, cerebroside B, cerebroside D, cytochalasin D, epoxycytochalasin D, cytochalasin C, loganin, cerevisterol, ergosta-7,22-dien-3beta, 5alpha, 6alpha-triol, ergosta-4,6,8(14),22-tetraen-3-one, ergosterol peroxide and ergosta-5,7,22-trien-3-ol, was isolated from ethyl acetate fraction of Engleromyces goetzei P. Henn. The structure of new ceramide (1) was elucidated by spectral data and chemical method, especially by 2D-NMR techniques. All of the compounds except cytochalasin D were first obtained from this fungus.
