Changes in the surface structure of cell membrane and the contents of membrane pro- teins and nuclear DNA of human gastric cancer (BGC-823) cells treated with organotin compound (Et_2SnCl_2phen) were studied with a sc...Changes in the surface structure of cell membrane and the contents of membrane pro- teins and nuclear DNA of human gastric cancer (BGC-823) cells treated with organotin compound (Et_2SnCl_2phen) were studied with a scanning electron microscope (SEM),a scanning tunneling,micro- scope (STM),and a cytofluorophotometer.It was found that Et_2SnCl_2Phen not only inhibited the cell growth but also remarkably changed the surface structure of the membrane of cancer cells.The surface of Et_2SnCl_2phen treated cancer cells was relatively smooth and showed fewer microvilli under SEM. STM images showed an uneven and loose distribution of the surface of the cell.In comparison with the untreated cancer cells,there was an evident decrease in the content of membrane proteins and nuclear DNA in Et_2SnCl_2phen treated cells.展开更多
The title compound {[（C6H5CH2）2Sn]2（O）（Cl2）}2 has been synthesized by the reaction of bisbenzyltin dichloride with NaOH dilute solution, and its structure was determined by X-ray diffraction. The crystal belongs...The title compound {[（C6H5CH2）2Sn]2（O）（Cl2）}2 has been synthesized by the reaction of bisbenzyltin dichloride with NaOH dilute solution, and its structure was determined by X-ray diffraction. The crystal belongs to monoclinic, space group C2/c, with a = 2.5081（17）, b = 1.0089（7）, c = 2.0909（14） nm, β = 94.267（8）°, V= 5.276（6） nm^3, Z = 4, De= 1.734 g/cm^3,μ（MoKa） = 21.55 cm^-1, F（000） = 2704, R = 0.0398 and Rw = 0.1024. According to structural analysis, the tin atom adopts a distorted five-coordinate trigonal bipyramidal geometry, and the ladder-like structure is shaped by one planar four-membered Sn2O2 ring together with two planar four-membered Sn2OCl rings.展开更多
Correlation relationships of 10 topological indices and molar refraction for 47 struc- turally-complicated organotins which included 16 ionic compounds R_mSnX_(4-m) and 31 covalent ones R_4Sn that is 41 aliphatic comp...Correlation relationships of 10 topological indices and molar refraction for 47 struc- turally-complicated organotins which included 16 ionic compounds R_mSnX_(4-m) and 31 covalent ones R_4Sn that is 41 aliphatic compounds(15 unsaturated and 26 saturated)and 6 aromatic ones were studied.Suitability of these ten topological parameters for describing the structure of elemental or- ganic compounds was then evaluated according to the correlation results.Two lately improved molecular connectivity indices(MCIs)-radius-corrected MCI ~1X^r and bond-length-corrected MCI ~1X^b were applied and proved to be most suitable for the structure expression in QSA(P)R studies of organotins or other elemental organic compounds.展开更多
This pioneered study is aimed to determine the levels and distributions of organotin compounds (OTCs) in sediment samples collected from five Egyptian lakes located in the southern-eastern Mediterranean Sea. The paper...This pioneered study is aimed to determine the levels and distributions of organotin compounds (OTCs) in sediment samples collected from five Egyptian lakes located in the southern-eastern Mediterranean Sea. The paper has given an account of and the reasons for the widespread distribution of Tributyltin (TBT) in northern lakes. The percentage of TBT ranged from 4% - 100% OTC revealing recent inputs of TBT. The highest average of TBT (2.84 μg/g Sn dry wt) was measured in lake Edku. Dibutyltin (DBT) was observed at most sampled sites. Relatively higher abundance of DBT was observed in sediments of EL-Burullus (0.69 μg/g Sn dry wt). One of most significant findings to emerge from this study is the absence of any strong and significant correlation between TBT and DBT in sediments from five northern lakes. The absence of such correlation might give a clear evidence that both compounds did not come from the same source. The observed OTC levels indicate some highly localized areas of contamination which are severe enough to cause harmful effects on marine flora and fauna. Except for El-Burllus, Triphenyltin (TPhT) was not measured in sediments of most stations. TPhT was the predominant species in El-Burullus, which indicate a source of pollution mostly originated from industrial and agricultural waste water discharge, organic wastes, commercial fertilizers, chemical wastes and pesticides. The percentages of OTC to total tin ranged from 1% to 35%. El-Brullus, Edku and El-Bardaweel exhibited the highest percentages. As a result of lack of enforcement on the control of OTC, the study has thrown up many questions need further detailed environmental assessment of OTC.展开更多
文摘Changes in the surface structure of cell membrane and the contents of membrane pro- teins and nuclear DNA of human gastric cancer (BGC-823) cells treated with organotin compound (Et_2SnCl_2phen) were studied with a scanning electron microscope (SEM),a scanning tunneling,micro- scope (STM),and a cytofluorophotometer.It was found that Et_2SnCl_2Phen not only inhibited the cell growth but also remarkably changed the surface structure of the membrane of cancer cells.The surface of Et_2SnCl_2phen treated cancer cells was relatively smooth and showed fewer microvilli under SEM. STM images showed an uneven and loose distribution of the surface of the cell.In comparison with the untreated cancer cells,there was an evident decrease in the content of membrane proteins and nuclear DNA in Et_2SnCl_2phen treated cells.
基金Supported by the Science and Technology Fund of Hunan Province (2007FJ4140)the Key Fund of Education Committee of Hunan Province (06009)the Construct Program of the Key Discipline in Hunan Province
文摘The title compound {[（C6H5CH2）2Sn]2（O）（Cl2）}2 has been synthesized by the reaction of bisbenzyltin dichloride with NaOH dilute solution, and its structure was determined by X-ray diffraction. The crystal belongs to monoclinic, space group C2/c, with a = 2.5081（17）, b = 1.0089（7）, c = 2.0909（14） nm, β = 94.267（8）°, V= 5.276（6） nm^3, Z = 4, De= 1.734 g/cm^3,μ（MoKa） = 21.55 cm^-1, F（000） = 2704, R = 0.0398 and Rw = 0.1024. According to structural analysis, the tin atom adopts a distorted five-coordinate trigonal bipyramidal geometry, and the ladder-like structure is shaped by one planar four-membered Sn2O2 ring together with two planar four-membered Sn2OCl rings.
基金This work was supported by the National Natural Science Foundation of China
文摘Correlation relationships of 10 topological indices and molar refraction for 47 struc- turally-complicated organotins which included 16 ionic compounds R_mSnX_(4-m) and 31 covalent ones R_4Sn that is 41 aliphatic compounds(15 unsaturated and 26 saturated)and 6 aromatic ones were studied.Suitability of these ten topological parameters for describing the structure of elemental or- ganic compounds was then evaluated according to the correlation results.Two lately improved molecular connectivity indices(MCIs)-radius-corrected MCI ~1X^r and bond-length-corrected MCI ~1X^b were applied and proved to be most suitable for the structure expression in QSA(P)R studies of organotins or other elemental organic compounds.
文摘This pioneered study is aimed to determine the levels and distributions of organotin compounds (OTCs) in sediment samples collected from five Egyptian lakes located in the southern-eastern Mediterranean Sea. The paper has given an account of and the reasons for the widespread distribution of Tributyltin (TBT) in northern lakes. The percentage of TBT ranged from 4% - 100% OTC revealing recent inputs of TBT. The highest average of TBT (2.84 μg/g Sn dry wt) was measured in lake Edku. Dibutyltin (DBT) was observed at most sampled sites. Relatively higher abundance of DBT was observed in sediments of EL-Burullus (0.69 μg/g Sn dry wt). One of most significant findings to emerge from this study is the absence of any strong and significant correlation between TBT and DBT in sediments from five northern lakes. The absence of such correlation might give a clear evidence that both compounds did not come from the same source. The observed OTC levels indicate some highly localized areas of contamination which are severe enough to cause harmful effects on marine flora and fauna. Except for El-Burllus, Triphenyltin (TPhT) was not measured in sediments of most stations. TPhT was the predominant species in El-Burullus, which indicate a source of pollution mostly originated from industrial and agricultural waste water discharge, organic wastes, commercial fertilizers, chemical wastes and pesticides. The percentages of OTC to total tin ranged from 1% to 35%. El-Brullus, Edku and El-Bardaweel exhibited the highest percentages. As a result of lack of enforcement on the control of OTC, the study has thrown up many questions need further detailed environmental assessment of OTC.
