Trichloroethylene (TCE) is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TC...Trichloroethylene (TCE) is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TCE cytotoxicity have been made in cultured liver cells. However, the molecular mechanisms by which TCE induces hepatotoxicity are not well understood. SET (also known as protein phosphatase 2A inhibitor, 12PP2A, or template-activating factor-I, TAF-D is a nuclear protein that regulates histone modification, gene transcription, DNA replication, nucleosome assembly,展开更多
Introduction Integrins are a large family of adhesion molecules broadly expressed on the surface of a wide variety of cells as heterodimers. Binding of integrins to ligands provides not only mechanical anchorage for t...Introduction Integrins are a large family of adhesion molecules broadly expressed on the surface of a wide variety of cells as heterodimers. Binding of integrins to ligands provides not only mechanical anchorage for the cell to another cell or展开更多
Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for t...Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for the demonstration of various protein constituents, indicated a gradual decrease in the intensity of staining reactions of the cytoplasmic material, suggesting a loss of protein moieties from the club cells and the epithelial cells of the opercular epidermis as a result of detergent exposure. 1990 Academic Press.Inc.展开更多
To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ...To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ASODN was transfected into SMMC-7721 cells mediated by DOTAP liposomal reagent.Electron microscopy,flow cytometry and RT-PCR were used to detect the changes in cell ultrastructure,apoptosis,cell cycle and the expression of cyclinB1 mRNA,respectively.Results After transfection of survivin ASODN,the expression of cyclinB1 mRNA in the cells significantly increased and increase in G2-M arrest and apoptosis appeared.Meanwhile,the cell ultrastructure had apoptotic changes such as chromatin condensation and apoptotic body formation.Conclusion Survivin ASODN can induce the expression of cyclinB1 that may result in G2-M arrest.Consequently,apoptosis is triggered.Survivin ASODN transfection might be an improtant new treatment for HCC.14 refs,2 figs,1 tab.展开更多
AIM:To compare and evaluate the phacoemulsification parameters and postoperative endothelial cell changes of two different phacoemulsification machines, each with different modes, but also to assess the relationship b...AIM:To compare and evaluate the phacoemulsification parameters and postoperative endothelial cell changes of two different phacoemulsification machines, each with different modes, but also to assess the relationship between postoperative endothelial cell loss and the phacoemulsification parameters, as well as the other factors in both groups.METHODS:This prospective observational study was comprised of consecutive eligible cataract patients operated with phacoemulsification technique performed by the same surgeon using either a WHITESTAR Signature Ellips FX(transversal, group 1) or Infiniti OZil IP(torsional, group 2) machine.RESULTS:The study included 86 patients. Baseline characteristics in the groups were similar. The median nuclear sclerosis grade was 3(2-4) in the first group and2(2-4) in the second group(P =0.265). Both groups had similar phacoemulsification needle times(group 1: 60.63±36 s; group 2: 55.98±30 s; P =0.789). The percentage of endothelial cell loss 30 d after surgery ranged from 3% to15% with a median of 7% in group 1, and from 2% to13% with a median of 6% in group 2; however, there was no statistically significant difference between the groups(P =0.407). Hexagonality(P =0.794) and the coefficient of variation(CV; P =0.142) did not differ significantly between the groups before and 30 d after surgery. Asignificant positive correlation was found between the endothelial cell loss and nuclear sclerosis grade(group1: P 【0.001; group 2: P 【0.001) and between the endothelial cell loss and average phacoemulsification power(group 1: P =0.007; group 2: P =0.008).CONCLUSION:Both of these machines were efficient,with similar endothelial cell loss. This endothelial cell loss was related to the increased nuclear sclerosis grade and increased phacoemulsification power.展开更多
:AIM To construct Hsp90 antisense RNAeukaryotic expression vector, transfect it intoSGC7901 and SGC7901/VCR of MDR-type humangastric cancer cell lines, HCC7402 of humanhepatic cancer and Eel09 of human esophagealcance...:AIM To construct Hsp90 antisense RNAeukaryotic expression vector, transfect it intoSGC7901 and SGC7901/VCR of MDR-type humangastric cancer cell lines, HCC7402 of humanhepatic cancer and Eel09 of human esophagealcancer cell lines, and to study the cell cycledistribution of the gene transected cells andtheir response to chemotherapeutic drugs.METHODS A I .03kb cDNA sequence of Hsp90Pwas obtained from the primary plasmid phHsp90by EcoR 1 and BamH I nuclease digestion andwas cloned to the EcoR 1 and BamH 1 site ofthe pcDNA by T4DNA ligase and an antisenseorientation of Hsp900 expression vector wasconstructed. The constructs were transfectedwith lipofectamine and positive clones wereselected with G418. The expression of RNA wasdetermined with dot blotting and RNaseprotection assay, and the expression of Hsp90protein determined with Western blot. Cell cycledistribution of the transfectants was analyzedwith flow cytometry, and the drug sensitivity ofthe transfectants to adriamycin (ADR ),vincrinstine (VCR ), mitomycin (MMC ) andcyclophosphamide (CTX ) with MTT andintracellular drug concentration of thetransfectants was determined with flowcytometry.RESULTS In EcoR 1 and BamH I restrictionanalysis, the size and the direction of the clonedsequence of Hsp900 remained what had beendesigned and the gene constructs were namedpcDNA-Hsp90. AH^SGC7901, AH^SGC7901/ VCR,AH-HCC7402 and AH-Eel09 cell clones allexpressed Hsp90 anti--sense RNA. Theexpression of Hsp90 was down--regulated in AHSGC7901, AH--SGC7901/ VCR, AH-HCC7402 andAH--Eel09 cell clones. Cell cycle distribution waschanged differently. In AH-SGC7901/ VCR andAH-Ec109 cells, G, phase cells were increased; Sphase and G, phase cells were decreased ascompared with their parental cell lines. In AHSGC7901 cell, G, phase cells were decreased, Qphase cells increased and S phase cells were notchanged, and in AH-HCC7402 cells G,, S and qphase cells remained unchanged as comparedwith their parental cell lines. The sensitivity ofAH--SGC7901, AH--SGC7901/ VCR, AH-HCC7402 andAH-Ec109 to chemotherapeutic drugs, thesensitivity ot AH--SGC7901/ VCR to ADR, VCR,MMC and CTX the sensitivity of AH-HCC7402 toADR and VCR, and the sensitivity of Eel09 toADR, VCR and CTX all increased as comparedwith their parental cell lines. The meanfluorescence intensity of ADR in AH--SGC7901,AH-SGC7901/ VCR, AH--HCC7402 and AH-Ec109was also significantly elevated (P< 0. 05).CONCLUSION Down-regulation of HsP90 couldchange cell cycle distribution and increase thedrug sensitivity of tumor cells.展开更多
Professor Duzheng YE(Tu-cheng YEH) was decades ahead of his time in proposing a model experiment to investigate whether abrupt seasonal changes of the general circulation can arise through circulation feedbacks alon...Professor Duzheng YE(Tu-cheng YEH) was decades ahead of his time in proposing a model experiment to investigate whether abrupt seasonal changes of the general circulation can arise through circulation feedbacks alone, unrelated to underlying inhomogeneities at the lower boundary. Here, we introduce Professor YEH's ideas during the 1950 s and 1960 s on the general circulation and summarize the results and suggestions of Yeh et al.(1959) on abrupt seasonal changes. We then review recent advances in understanding abrupt seasonal changes arising from model experiments like those proposed by Yeh et al.(1959). The model experiments show that circulation feedbacks can indeed give rise to abrupt seasonal transitions.In these transitions, large-scale eddies that originate in midlatitudes and interact with the zonal mean flow and meridional overturning circulations in the tropics play central roles.展开更多
The seedlings of three rice varieties (Damagu,Ligeng 2, and Xiuzinuo) were cultivated at 25 ±1℃. After chilling injury (at 2~C), blacksediments of lead phosphate appeared on plas-
Fluorescence microscopy, as a sensitive method to detect microenvironment of molecules, is widely used in protein conformation and dynamic studies in live cells. Fluorescence lifetime imaging microscopy(FLIM), which...Fluorescence microscopy, as a sensitive method to detect microenvironment of molecules, is widely used in protein conformation and dynamic studies in live cells. Fluorescence lifetime imaging microscopy(FLIM), which is independent of fluorophore concentrations, scattering and bleaching, is a suitable tool to analyze membrane proteins in a single cell. Ferroportin(FPN), a multi-ion exporter in vertebrates, was modulated by metal ions with unknown mechanism. Herein, we fused green fluorescence protein on Cterminal of FPN(FPN-eGFP) and applied fluorescence lifetime to monitor conformation changes of FPN in a live cell. The fluorescence lifetime distribution showed a shift to shorter lifetime upon Mn^(2+) treatment,suggesting a preference conformation of FPN in Mn^(2+) exposure. It is also observed that the lifetime(rather than intensity) measurement was not strongly influenced by laser power. The observed fluorescence lifetime changes of FPN-eGFP upon Mn^(2+) treatments indicated that extracellular metal ions can modulate FPN through conformation exchanges between several different states.展开更多
基金supported by NSFC (the National Natural Science Foundation of China) [81273126, 30972454]the Key Project of Guangdong Natural Science Foundation [S2012020010903]+2 种基金the Project of Shenzhen Basic Research Plan [JCYJ20120616 154222545]the Upgrade Scheme of Shenzhen Municipal Key Laboratory [CXB201005260068A]Medical Scientific Research Foundation of Guangdong Province (A2012577)
文摘Trichloroethylene (TCE) is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TCE cytotoxicity have been made in cultured liver cells. However, the molecular mechanisms by which TCE induces hepatotoxicity are not well understood. SET (also known as protein phosphatase 2A inhibitor, 12PP2A, or template-activating factor-I, TAF-D is a nuclear protein that regulates histone modification, gene transcription, DNA replication, nucleosome assembly,
基金supported by US National Institutes of Health grant R01 AI44902 (to C Z )a Pre-doctoral Fellowship from the American Heart Association (to W C )
文摘Introduction Integrins are a large family of adhesion molecules broadly expressed on the surface of a wide variety of cells as heterodimers. Binding of integrins to ligands provides not only mechanical anchorage for the cell to another cell or
文摘Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for the demonstration of various protein constituents, indicated a gradual decrease in the intensity of staining reactions of the cytoplasmic material, suggesting a loss of protein moieties from the club cells and the epithelial cells of the opercular epidermis as a result of detergent exposure. 1990 Academic Press.Inc.
文摘To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ASODN was transfected into SMMC-7721 cells mediated by DOTAP liposomal reagent.Electron microscopy,flow cytometry and RT-PCR were used to detect the changes in cell ultrastructure,apoptosis,cell cycle and the expression of cyclinB1 mRNA,respectively.Results After transfection of survivin ASODN,the expression of cyclinB1 mRNA in the cells significantly increased and increase in G2-M arrest and apoptosis appeared.Meanwhile,the cell ultrastructure had apoptotic changes such as chromatin condensation and apoptotic body formation.Conclusion Survivin ASODN can induce the expression of cyclinB1 that may result in G2-M arrest.Consequently,apoptosis is triggered.Survivin ASODN transfection might be an improtant new treatment for HCC.14 refs,2 figs,1 tab.
文摘AIM:To compare and evaluate the phacoemulsification parameters and postoperative endothelial cell changes of two different phacoemulsification machines, each with different modes, but also to assess the relationship between postoperative endothelial cell loss and the phacoemulsification parameters, as well as the other factors in both groups.METHODS:This prospective observational study was comprised of consecutive eligible cataract patients operated with phacoemulsification technique performed by the same surgeon using either a WHITESTAR Signature Ellips FX(transversal, group 1) or Infiniti OZil IP(torsional, group 2) machine.RESULTS:The study included 86 patients. Baseline characteristics in the groups were similar. The median nuclear sclerosis grade was 3(2-4) in the first group and2(2-4) in the second group(P =0.265). Both groups had similar phacoemulsification needle times(group 1: 60.63±36 s; group 2: 55.98±30 s; P =0.789). The percentage of endothelial cell loss 30 d after surgery ranged from 3% to15% with a median of 7% in group 1, and from 2% to13% with a median of 6% in group 2; however, there was no statistically significant difference between the groups(P =0.407). Hexagonality(P =0.794) and the coefficient of variation(CV; P =0.142) did not differ significantly between the groups before and 30 d after surgery. Asignificant positive correlation was found between the endothelial cell loss and nuclear sclerosis grade(group1: P 【0.001; group 2: P 【0.001) and between the endothelial cell loss and average phacoemulsification power(group 1: P =0.007; group 2: P =0.008).CONCLUSION:Both of these machines were efficient,with similar endothelial cell loss. This endothelial cell loss was related to the increased nuclear sclerosis grade and increased phacoemulsification power.
基金Project supported by the National Natural Science Foundation of China,No.39570806National Excel1ent Youth Scientific Foundation,No.3952020.
文摘:AIM To construct Hsp90 antisense RNAeukaryotic expression vector, transfect it intoSGC7901 and SGC7901/VCR of MDR-type humangastric cancer cell lines, HCC7402 of humanhepatic cancer and Eel09 of human esophagealcancer cell lines, and to study the cell cycledistribution of the gene transected cells andtheir response to chemotherapeutic drugs.METHODS A I .03kb cDNA sequence of Hsp90Pwas obtained from the primary plasmid phHsp90by EcoR 1 and BamH I nuclease digestion andwas cloned to the EcoR 1 and BamH 1 site ofthe pcDNA by T4DNA ligase and an antisenseorientation of Hsp900 expression vector wasconstructed. The constructs were transfectedwith lipofectamine and positive clones wereselected with G418. The expression of RNA wasdetermined with dot blotting and RNaseprotection assay, and the expression of Hsp90protein determined with Western blot. Cell cycledistribution of the transfectants was analyzedwith flow cytometry, and the drug sensitivity ofthe transfectants to adriamycin (ADR ),vincrinstine (VCR ), mitomycin (MMC ) andcyclophosphamide (CTX ) with MTT andintracellular drug concentration of thetransfectants was determined with flowcytometry.RESULTS In EcoR 1 and BamH I restrictionanalysis, the size and the direction of the clonedsequence of Hsp900 remained what had beendesigned and the gene constructs were namedpcDNA-Hsp90. AH^SGC7901, AH^SGC7901/ VCR,AH-HCC7402 and AH-Eel09 cell clones allexpressed Hsp90 anti--sense RNA. Theexpression of Hsp90 was down--regulated in AHSGC7901, AH--SGC7901/ VCR, AH-HCC7402 andAH--Eel09 cell clones. Cell cycle distribution waschanged differently. In AH-SGC7901/ VCR andAH-Ec109 cells, G, phase cells were increased; Sphase and G, phase cells were decreased ascompared with their parental cell lines. In AHSGC7901 cell, G, phase cells were decreased, Qphase cells increased and S phase cells were notchanged, and in AH-HCC7402 cells G,, S and qphase cells remained unchanged as comparedwith their parental cell lines. The sensitivity ofAH--SGC7901, AH--SGC7901/ VCR, AH-HCC7402 andAH-Ec109 to chemotherapeutic drugs, thesensitivity ot AH--SGC7901/ VCR to ADR, VCR,MMC and CTX the sensitivity of AH-HCC7402 toADR and VCR, and the sensitivity of Eel09 toADR, VCR and CTX all increased as comparedwith their parental cell lines. The meanfluorescence intensity of ADR in AH--SGC7901,AH-SGC7901/ VCR, AH--HCC7402 and AH-Ec109was also significantly elevated (P< 0. 05).CONCLUSION Down-regulation of HsP90 couldchange cell cycle distribution and increase thedrug sensitivity of tumor cells.
基金support from the LASG during his visit to the labsupported by the National Nature Science Foundation of China (Grant No. 4157060636)the Hundred Talents Program of Sun Yat-sen University
文摘Professor Duzheng YE(Tu-cheng YEH) was decades ahead of his time in proposing a model experiment to investigate whether abrupt seasonal changes of the general circulation can arise through circulation feedbacks alone, unrelated to underlying inhomogeneities at the lower boundary. Here, we introduce Professor YEH's ideas during the 1950 s and 1960 s on the general circulation and summarize the results and suggestions of Yeh et al.(1959) on abrupt seasonal changes. We then review recent advances in understanding abrupt seasonal changes arising from model experiments like those proposed by Yeh et al.(1959). The model experiments show that circulation feedbacks can indeed give rise to abrupt seasonal transitions.In these transitions, large-scale eddies that originate in midlatitudes and interact with the zonal mean flow and meridional overturning circulations in the tropics play central roles.
文摘The seedlings of three rice varieties (Damagu,Ligeng 2, and Xiuzinuo) were cultivated at 25 ±1℃. After chilling injury (at 2~C), blacksediments of lead phosphate appeared on plas-
基金supported by the National Key R&D Program of China (Nos. 2016YFA0400900, 2017YFA0505300)the Instrument Developing Project of the Chinese Academy of Sciences (No. YZ201564)
文摘Fluorescence microscopy, as a sensitive method to detect microenvironment of molecules, is widely used in protein conformation and dynamic studies in live cells. Fluorescence lifetime imaging microscopy(FLIM), which is independent of fluorophore concentrations, scattering and bleaching, is a suitable tool to analyze membrane proteins in a single cell. Ferroportin(FPN), a multi-ion exporter in vertebrates, was modulated by metal ions with unknown mechanism. Herein, we fused green fluorescence protein on Cterminal of FPN(FPN-eGFP) and applied fluorescence lifetime to monitor conformation changes of FPN in a live cell. The fluorescence lifetime distribution showed a shift to shorter lifetime upon Mn^(2+) treatment,suggesting a preference conformation of FPN in Mn^(2+) exposure. It is also observed that the lifetime(rather than intensity) measurement was not strongly influenced by laser power. The observed fluorescence lifetime changes of FPN-eGFP upon Mn^(2+) treatments indicated that extracellular metal ions can modulate FPN through conformation exchanges between several different states.