目的研究葛根素对极低频电磁场(ELF-EMF)作用下人视网膜色素上皮(RPE)细胞病理改变的影响,探讨其在近视防治中的可能作用。方法实验细胞分为对照组、辐射组、葛根素组(终浓度100μmol/L)。CCK8检测RPE细胞的增殖活性,Real-time PCR法检...目的研究葛根素对极低频电磁场(ELF-EMF)作用下人视网膜色素上皮(RPE)细胞病理改变的影响,探讨其在近视防治中的可能作用。方法实验细胞分为对照组、辐射组、葛根素组(终浓度100μmol/L)。CCK8检测RPE细胞的增殖活性,Real-time PCR法检测RPE细胞中转化生长因子-β2(TGF-β2)m RNA的表达情况。ELISA检测RPE细胞培养上清中TGF-β2的蛋白含量。结果与对照组相比,辐射组RPE细胞增殖活性降低;TGF-β2 m RNA表达增高,RPE细胞上清中TGF-β2含量上调。与辐射组相比,葛根素组RPE细胞增殖活性增高,TGF-β2 m RNA表达降低,RPE细胞上清中TGF-β2含量下调,差异有统计学意义。结论ELF-EMF在一定范围内影响体外培养的RPE细胞的增殖活性及TGF-β2的表达与分泌,葛根素在一定程度上逆转了这一作用。展开更多
OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).MET...OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).METHODS:Cultured HFSFs were exposed to 0.2mT ELF-EMF for 24 h.The experimental groups were divided into subgroups treated with 0,0.1,1and 10μM puerarin respectively.The expression of MMP-2 mRNA and protein were detected with real-time polymerase chain reaction and western-blot analysis respectively.RESULTS:MMP-2 mRNA and protein expression increased by 0.793 and 1.130 folds respectively under the exposure of ELF-EMFs at 0.2 mT flux density for24 h.Puerarin at the concentration of 0.1μM reversed this effect by 8.53%in mRNA and by 17.97%in protein expression(P<0.05).The effect was more prominent at higher concentrations(1 and 10μM,P<0.01).CONCLUSION:Exposure to ELF-EMFs increased the expression of MMP-2 mRNA and protein in HFSF cells.Puerarin reversed the action to some extent in a specific concentration range.Our results implied that the puerarin might protect scleral tissue from increased expression induced by exposure to ELF-EMFs.展开更多
The effect of a rotating magnetic field(RMF)on the distribution of Al_(2)O_(3)particles with an Al melt was studied by means of simulation and experiment.The results show that Al_(2)O_(3)particles(diameter of 1-10μm,...The effect of a rotating magnetic field(RMF)on the distribution of Al_(2)O_(3)particles with an Al melt was studied by means of simulation and experiment.The results show that Al_(2)O_(3)particles(diameter of 1-10μm,1wt.%)are significantly agglomerated at the top of ingots when subjected to an RMF,and their distribution is influenced by both the intensity and the duration of RMF application.The optimal separation efficiency is achieved with the magnetic intensity of 12 mT for 120 s.The number of the particles at the bottom and the middle decreases by 64.5%and 69.7%,respectively,while that at the top increases by 242.5%compared to the condition without an RMF.However,if further increase the intensity or the duration of RMF,it can induce turbulent flows that draw some of the separated Al_(2)O_(3)particles back into the melt,reducing separation efficiency.The calculation results show that as the magnetic intensity increases from 6 mT to 18 mT,the velocity difference between the particles and the Al melt flow quadruples,increasing from 0.013 m·s^(-1)to 0.066 m·s^(-1).Driven by this velocity difference,centrifugal motion,and secondary circulation,Al_(2)O_(3)particles tend to migrate upwards within the melt,facilitating the separation of impurity particles and enhancing the purity of the melt.展开更多
The effects of directional solidification parameters and the coupling of directional solidification parameters and alternating electromagnetic fields on separation and enrichment of the C54–TiSi2 phase were investiga...The effects of directional solidification parameters and the coupling of directional solidification parameters and alternating electromagnetic fields on separation and enrichment of the C54–TiSi2 phase were investigated in a directionally solidified hypoeutectic Ti–65 wt.%Si alloy.The results indicated that by increasing the pull-down velocity at a given position within the ingot,the cooling rate,growth rate,and temperature gradient of ingot could be increased.At a pull-down velocity near 5μm/s,the temperature gradient,cooling rate,and growth rate decreased with increasing the thickness of the C54–TiSi2-rich layer.Electromagnetic fields enhanced mass transfer at pull-down velocities of 5,10,15,and 20μm/s,with resulting enriched layer thicknesses of 15,10,10,and 5 mm,respectively.By increasing the percentage of Ti in the Ti–Si alloy from 25 to 35 wt.%,the thickness of the C54–TiSi2-rich layer was increased from 2.5 to 3.3 cm.However,the maximum C54–TiSi2 content obtained experimentally in this layer decreased from 92.06 to 79.49 mass%.展开更多
OBJECTIVE: To evaluate the protective effect of puerarin [an isoflavone compound extracted from Gegen(Radix Puerariae Lobatae)] in scleral remodeling induced by extremely low frequency electromagnetic fields(ELF-EMFs)...OBJECTIVE: To evaluate the protective effect of puerarin [an isoflavone compound extracted from Gegen(Radix Puerariae Lobatae)] in scleral remodeling induced by extremely low frequency electromagnetic fields(ELF-EMFs).METHODS: Human fetal scleral fibroblasts(HFSFs)were divided into 5 groups:(a) untreated controls;(b) cells treated with ELF-EMFs;(c) cells treated with ELF-EMFs and puerarin 0.1 μM;(d) cells treated with ELF-EMFs and puerarin 1 μM;(e) cells treated with ELF-EMFs and puerarin 10 μM. Cell proliferation activity was measured by the cell-counting kit-8 assay. Matrix metalloproteinase-2(MMP-2) activity was measured by gelatin enzymography.MMP-2 and collagenⅠ(COL1A1) m RNA, protein expression were measured by Real-Time polymerase chain reaction, Western blot analysis, respectively.RESULTS: Puerarin reduced the inhibition in cell proliferation, MMP-2 activity, m RNA, protein expression of HFSFs exposed to ELF-EMFs and enhanced the COL1A1 m RNA and protein expression.CONCLUSION: Puerarin was found to participate in the matrix remodeling process. It might be a potential agent for the treatment of extracellular matrix degradation of sclera associated with ocular conditions.展开更多
Cu-36 wt%Zn alloy is widely used in valves of water and heating and auto parts,etc.Nevertheless,the structure is still coarse,and performances are much poor.The structure and performances of Cu-36 wt%Zn alloy were inv...Cu-36 wt%Zn alloy is widely used in valves of water and heating and auto parts,etc.Nevertheless,the structure is still coarse,and performances are much poor.The structure and performances of Cu-36 wt%Zn alloy were investigated by adding Al_(2)O_(3)nanoparticles and stirring.Results indicate that by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring,the Cu-36 wt%Zn alloy with refined microstructure was successfully prepared.The average grain size is refined by 99%compared with that without nanoparticles and stirring.The tensile strength(R_m)and percentage elongation after fracture(A11.3)increase by 20.58%and 19.40%,respectively,compared with that without nanoparticles and stirring.Nanoparticles increase heterogeneous nucleation rate by 50%compared with that without nanoparticles.The depth of dezincification layer decreases by 78.71%compared with that without nanoparticles and stirring,as protective layer(Cu-Al_(2)O_(3)-Zn)is completely formed around the grain boundaries.展开更多
In-situ TiB_2/AZ31 composites were prepared by utilizing the SHS reaction of Al-Ti-B system in the molten magnesium,and the effects of external physical fields on the dispersion of TiB_2 particles were investigated.Th...In-situ TiB_2/AZ31 composites were prepared by utilizing the SHS reaction of Al-Ti-B system in the molten magnesium,and the effects of external physical fields on the dispersion of TiB_2 particles were investigated.The results show that high-energy ultrasonic vibration could effectively break up the particle clusters and make the TiB2 particles uniformly distributed in the melt of TiB_2/AZ31 composites.The compound field(high-energy ultrasonic field coupling with electromagnetic field)could not only distribute the TiB_2 particles into the matrix uniformly,but also make the grains of α-Mg free and uniform further than the ultrasonic field solo.The average grain size of as-cast TiB_2/AZ31 composites was reduced from 173μm to 94μm.展开更多
文摘目的研究葛根素对极低频电磁场(ELF-EMF)作用下人视网膜色素上皮(RPE)细胞病理改变的影响,探讨其在近视防治中的可能作用。方法实验细胞分为对照组、辐射组、葛根素组(终浓度100μmol/L)。CCK8检测RPE细胞的增殖活性,Real-time PCR法检测RPE细胞中转化生长因子-β2(TGF-β2)m RNA的表达情况。ELISA检测RPE细胞培养上清中TGF-β2的蛋白含量。结果与对照组相比,辐射组RPE细胞增殖活性降低;TGF-β2 m RNA表达增高,RPE细胞上清中TGF-β2含量上调。与辐射组相比,葛根素组RPE细胞增殖活性增高,TGF-β2 m RNA表达降低,RPE细胞上清中TGF-β2含量下调,差异有统计学意义。结论ELF-EMF在一定范围内影响体外培养的RPE细胞的增殖活性及TGF-β2的表达与分泌,葛根素在一定程度上逆转了这一作用。
基金Supported by the General Program of the Bio-medical Division of the Shanghai Science and Technology Commission(10411966200)the Scientific Research Fund of Chinese Medical of Shanghai Health Bureau(2009s023)the Shanghai Leading Academic Discipline Project(S30205)
文摘OBJECTIVE:To study the effect of puerarin on matrix metalloproteinase-2(MMP-2)gene and protein expression in human fetal scleral fibroblasts(HFSFs)exposed to extremely low frequency electromagnetic fields(ELF-EMF).METHODS:Cultured HFSFs were exposed to 0.2mT ELF-EMF for 24 h.The experimental groups were divided into subgroups treated with 0,0.1,1and 10μM puerarin respectively.The expression of MMP-2 mRNA and protein were detected with real-time polymerase chain reaction and western-blot analysis respectively.RESULTS:MMP-2 mRNA and protein expression increased by 0.793 and 1.130 folds respectively under the exposure of ELF-EMFs at 0.2 mT flux density for24 h.Puerarin at the concentration of 0.1μM reversed this effect by 8.53%in mRNA and by 17.97%in protein expression(P<0.05).The effect was more prominent at higher concentrations(1 and 10μM,P<0.01).CONCLUSION:Exposure to ELF-EMFs increased the expression of MMP-2 mRNA and protein in HFSF cells.Puerarin reversed the action to some extent in a specific concentration range.Our results implied that the puerarin might protect scleral tissue from increased expression induced by exposure to ELF-EMFs.
基金support of the National Natural Science Foundation of China(Nos.52171135 and 51971048).
文摘The effect of a rotating magnetic field(RMF)on the distribution of Al_(2)O_(3)particles with an Al melt was studied by means of simulation and experiment.The results show that Al_(2)O_(3)particles(diameter of 1-10μm,1wt.%)are significantly agglomerated at the top of ingots when subjected to an RMF,and their distribution is influenced by both the intensity and the duration of RMF application.The optimal separation efficiency is achieved with the magnetic intensity of 12 mT for 120 s.The number of the particles at the bottom and the middle decreases by 64.5%and 69.7%,respectively,while that at the top increases by 242.5%compared to the condition without an RMF.However,if further increase the intensity or the duration of RMF,it can induce turbulent flows that draw some of the separated Al_(2)O_(3)particles back into the melt,reducing separation efficiency.The calculation results show that as the magnetic intensity increases from 6 mT to 18 mT,the velocity difference between the particles and the Al melt flow quadruples,increasing from 0.013 m·s^(-1)to 0.066 m·s^(-1).Driven by this velocity difference,centrifugal motion,and secondary circulation,Al_(2)O_(3)particles tend to migrate upwards within the melt,facilitating the separation of impurity particles and enhancing the purity of the melt.
基金This research was supported by the National Natural Science Foundation of China(No.U1702251)Special Funds of State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(Grant No.CNMRCUTS1604)+2 种基金the Program for Innovative Research Team in University of Ministry of Education of China(No.IRT_17R48)Key Laboratory of Comprehensive Utilization of Vanadium and Titanium Resources in Sichuan Province(2019FTSZ06)the PhD Fund of Panzhihua University,and Funded by the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization.
文摘The effects of directional solidification parameters and the coupling of directional solidification parameters and alternating electromagnetic fields on separation and enrichment of the C54–TiSi2 phase were investigated in a directionally solidified hypoeutectic Ti–65 wt.%Si alloy.The results indicated that by increasing the pull-down velocity at a given position within the ingot,the cooling rate,growth rate,and temperature gradient of ingot could be increased.At a pull-down velocity near 5μm/s,the temperature gradient,cooling rate,and growth rate decreased with increasing the thickness of the C54–TiSi2-rich layer.Electromagnetic fields enhanced mass transfer at pull-down velocities of 5,10,15,and 20μm/s,with resulting enriched layer thicknesses of 15,10,10,and 5 mm,respectively.By increasing the percentage of Ti in the Ti–Si alloy from 25 to 35 wt.%,the thickness of the C54–TiSi2-rich layer was increased from 2.5 to 3.3 cm.However,the maximum C54–TiSi2 content obtained experimentally in this layer decreased from 92.06 to 79.49 mass%.
基金Supported by the General Program of the Bio-medical Division of the Shanghai Science and Technology Commission:Effect of Extremely Low Frequency Electromagnetic Fields on Myopia Based on RPE-sclera Complex(No.10411966200)the Scientific Research Fund of Chinese Medical of Shanghai Health Bureau:Effect of Puerarin on RPE Cells Exposed to ELF-EMF(No.2014JP015)
文摘OBJECTIVE: To evaluate the protective effect of puerarin [an isoflavone compound extracted from Gegen(Radix Puerariae Lobatae)] in scleral remodeling induced by extremely low frequency electromagnetic fields(ELF-EMFs).METHODS: Human fetal scleral fibroblasts(HFSFs)were divided into 5 groups:(a) untreated controls;(b) cells treated with ELF-EMFs;(c) cells treated with ELF-EMFs and puerarin 0.1 μM;(d) cells treated with ELF-EMFs and puerarin 1 μM;(e) cells treated with ELF-EMFs and puerarin 10 μM. Cell proliferation activity was measured by the cell-counting kit-8 assay. Matrix metalloproteinase-2(MMP-2) activity was measured by gelatin enzymography.MMP-2 and collagenⅠ(COL1A1) m RNA, protein expression were measured by Real-Time polymerase chain reaction, Western blot analysis, respectively.RESULTS: Puerarin reduced the inhibition in cell proliferation, MMP-2 activity, m RNA, protein expression of HFSFs exposed to ELF-EMFs and enhanced the COL1A1 m RNA and protein expression.CONCLUSION: Puerarin was found to participate in the matrix remodeling process. It might be a potential agent for the treatment of extracellular matrix degradation of sclera associated with ocular conditions.
基金financially supported by the National Natural Science Foundation of China(No.51571160)the Fundamental Research Fund for Taizhou Science and Technology(No.131KY02)+1 种基金the Public Welfare Projects of Science and Technology Department of Zhejiang Province(No.2015C31143)the Pivot Innovation Team of Shaanxi Electric Materials and Infiltration Technique(No.15JS071)。
文摘Cu-36 wt%Zn alloy is widely used in valves of water and heating and auto parts,etc.Nevertheless,the structure is still coarse,and performances are much poor.The structure and performances of Cu-36 wt%Zn alloy were investigated by adding Al_(2)O_(3)nanoparticles and stirring.Results indicate that by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring,the Cu-36 wt%Zn alloy with refined microstructure was successfully prepared.The average grain size is refined by 99%compared with that without nanoparticles and stirring.The tensile strength(R_m)and percentage elongation after fracture(A11.3)increase by 20.58%and 19.40%,respectively,compared with that without nanoparticles and stirring.Nanoparticles increase heterogeneous nucleation rate by 50%compared with that without nanoparticles.The depth of dezincification layer decreases by 78.71%compared with that without nanoparticles and stirring,as protective layer(Cu-Al_(2)O_(3)-Zn)is completely formed around the grain boundaries.
基金Item Sponsored by National High Technology Research and Development Program of China[No.2009AA03Z525]Aviation Science Foundation of China[No.20095263005]
文摘In-situ TiB_2/AZ31 composites were prepared by utilizing the SHS reaction of Al-Ti-B system in the molten magnesium,and the effects of external physical fields on the dispersion of TiB_2 particles were investigated.The results show that high-energy ultrasonic vibration could effectively break up the particle clusters and make the TiB2 particles uniformly distributed in the melt of TiB_2/AZ31 composites.The compound field(high-energy ultrasonic field coupling with electromagnetic field)could not only distribute the TiB_2 particles into the matrix uniformly,but also make the grains of α-Mg free and uniform further than the ultrasonic field solo.The average grain size of as-cast TiB_2/AZ31 composites was reduced from 173μm to 94μm.
