目的观察过敏性紫癜性肾炎(HSPN)患儿刺激系膜细胞-足细胞轴及直接刺激足细胞对细胞增殖及肿瘤坏死因子(TNF)-α分泌的影响,从而探讨在HSPN发病机制中IgA1引起足细胞损伤的作用机制。方法采用层析法获得HSPN患儿及健康儿童血清单聚体IgA...目的观察过敏性紫癜性肾炎(HSPN)患儿刺激系膜细胞-足细胞轴及直接刺激足细胞对细胞增殖及肿瘤坏死因子(TNF)-α分泌的影响,从而探讨在HSPN发病机制中IgA1引起足细胞损伤的作用机制。方法采用层析法获得HSPN患儿及健康儿童血清单聚体IgA1(mIgA1),并热聚合为聚合IgA1(aIgA1),分别采用HSPN患儿aIgA1与系膜细胞共培养上清(aIgA1-MES上清组)、HSPN患儿的aIgA1(HSPN组)及健康儿童的aIgA1(健康儿童组)刺激足细胞,三组均采用50、100、250μg/mL三种浓度的aIgA1;并设不含aIgA1的阴性对照组。采用噻唑蓝(MTT)法检测刺激24 h及48 h足细胞的增殖情况;收集培养48 h的细胞培养基上清,用酶聚免疫吸附测定(ELISA)法测定TNF-α的水平。对比分析不同浓度的aIgA1对细胞增殖和TNF-α分泌水平的影响。结果 24 h MTT结果显示,aIgA1-MES上清组刺激足细胞在aIgA1浓度为100、250μg/mL的aIgA1中OD值明显低于阴性对照组(P<0.05),HSPN组及健康儿童组aIgA1直接刺激足细胞不能对细胞增殖产生影响(P>0.05);48 h MTT结果显示,IgA1-MES上清组在三种aIgA1浓度下足细胞OD值明显低于阴性对照组(P<0.05),HSPN组及健康儿童组直接刺激足细胞不能对细胞增殖产生影响(P>0.05);三种aIgA1浓度的aIgA1-MES上清组刺激足细胞分泌TNF-α含量较阴性对照组明显升高(P<0.01),三种aIgA1浓度的HSPN组及健康儿童组TNF-α含量与阴性对照组比较,差异无统计学意义(P>0.05)。结论 HSPN患儿aIgA1不能直接刺激足细胞造成细胞损伤,而是通过系膜细胞-足细胞轴抑制足细胞的增殖,并诱导足细胞分泌TNF-α水平增加。展开更多
The plasma membrane vesicles were purified from soybean (Glycine max L.) hypocotyls by two_phase partitioning methods. The stimulatory effects of K + on the coupling between ATP hydrolysis and proton transport by th...The plasma membrane vesicles were purified from soybean (Glycine max L.) hypocotyls by two_phase partitioning methods. The stimulatory effects of K + on the coupling between ATP hydrolysis and proton transport by the plasma membrane H +_ATPase were studied. The results showed that the proton transport activity was increased by 850% in the presence of 100 mmol/L KCl, while ATP hydrolytic activity was only increased by 28.2%. Kinetic studies showed that K m of ATP hydrolysis decreased from 1.14 to 0.7 mmol/L, while V max of ATP hydrolysis increased from 285.7 to 344.8 nmol Pi·mg -1 protein·min -1 in the presence of KCl. Experiments showed that the optimum pH was 6.5 and 6.0 in the presence and absence of KCl, respectively. Further studies revealed that K + could promote the inhibitory effects of hydroxylamines and vanadates on the ATP hydrolytic activity. The above results suggested that K + could regulate the coupling between ATP hydrolysis and proton transport of the plasma membrane H +_ATPase through modulating the structure and function of the kinase and phosphatase domains of the plasma membrane H +_ATPase.展开更多
The stimulatory effect of lysophosphatidylcholine (lyso_PC) on ATP and ρ_nitrophenyl phosphate (PNPP) hydrolysis by the plasma membrane H +_ATPase from soybean (Glycine max (L.) Merr.) hypocotyls was studied. Re...The stimulatory effect of lysophosphatidylcholine (lyso_PC) on ATP and ρ_nitrophenyl phosphate (PNPP) hydrolysis by the plasma membrane H +_ATPase from soybean (Glycine max (L.) Merr.) hypocotyls was studied. Results showed that lyso_PC stimulated the hydrolysis of ATP; ATP hydrolysis was enhanced dramatically when lyso_PC was within 0-0.03%, and increased slightly when lyso_PC was higher than 0.03%. At the concentration of 0.03%, lyso_PC stimulated ATP hydrolysis by 80.5%. Kinetics analysis showed that V max increased from 0.46 μmol P i·mg -1 protein·min -1 to 0.87 μmol P i·mg -1 protein·min -1 while K m increased from 0.88 mmol/L to 1.15 mmol/L under lyso_PC treatment. The optimum pH of ATP hydrolysis was shifted from 6.5 to 7.0 . Moreover, it was found lyso_PC enhanced the inhibition of ATP hydrolysis by hydroxylamine. In the presence of 200 mmol/L hydroxylamine, ATP hydrolysis was inhibited by 74.4%, while it was inhibited by 84.4% when treated with lyso_PC. However, PNPP hydrolysis and the inhibitory effect of vanadate were not affected by lyso_PC. The above results indicated that the kinase domain might be an action site or regulatory region of the C_terminal autoinhibitory domain in the plant plasma membrane H +_ATPase.展开更多
ZnO films with c -axis parallel to the substrate are reported.ZnO films are synthesized by solid-source chemical vapor deposition,a novel CVD technique,using zinc acetate dihydrate (solid) as the source material.The p...ZnO films with c -axis parallel to the substrate are reported.ZnO films are synthesized by solid-source chemical vapor deposition,a novel CVD technique,using zinc acetate dihydrate (solid) as the source material.The properties are characterized by X-ray diffraction,atomic force microscopy and transmission spectra.The parallel oriented ZnO films with mixed orientation for (100) and (110) planes are achieved on glass at the substrate temperature of 200℃ and the source temperature of 280℃,and a qualitative explanation is given for the forming of the mixed orientation.AFM images show that the surface is somewhat rough for the parallel oriented ZnO films.The transmission spectrum exhibits a high transmittance of about 85% in the visible region and shows an optical band gap about 3.25eV at room temperature.展开更多
文摘目的观察过敏性紫癜性肾炎(HSPN)患儿刺激系膜细胞-足细胞轴及直接刺激足细胞对细胞增殖及肿瘤坏死因子(TNF)-α分泌的影响,从而探讨在HSPN发病机制中IgA1引起足细胞损伤的作用机制。方法采用层析法获得HSPN患儿及健康儿童血清单聚体IgA1(mIgA1),并热聚合为聚合IgA1(aIgA1),分别采用HSPN患儿aIgA1与系膜细胞共培养上清(aIgA1-MES上清组)、HSPN患儿的aIgA1(HSPN组)及健康儿童的aIgA1(健康儿童组)刺激足细胞,三组均采用50、100、250μg/mL三种浓度的aIgA1;并设不含aIgA1的阴性对照组。采用噻唑蓝(MTT)法检测刺激24 h及48 h足细胞的增殖情况;收集培养48 h的细胞培养基上清,用酶聚免疫吸附测定(ELISA)法测定TNF-α的水平。对比分析不同浓度的aIgA1对细胞增殖和TNF-α分泌水平的影响。结果 24 h MTT结果显示,aIgA1-MES上清组刺激足细胞在aIgA1浓度为100、250μg/mL的aIgA1中OD值明显低于阴性对照组(P<0.05),HSPN组及健康儿童组aIgA1直接刺激足细胞不能对细胞增殖产生影响(P>0.05);48 h MTT结果显示,IgA1-MES上清组在三种aIgA1浓度下足细胞OD值明显低于阴性对照组(P<0.05),HSPN组及健康儿童组直接刺激足细胞不能对细胞增殖产生影响(P>0.05);三种aIgA1浓度的aIgA1-MES上清组刺激足细胞分泌TNF-α含量较阴性对照组明显升高(P<0.01),三种aIgA1浓度的HSPN组及健康儿童组TNF-α含量与阴性对照组比较,差异无统计学意义(P>0.05)。结论 HSPN患儿aIgA1不能直接刺激足细胞造成细胞损伤,而是通过系膜细胞-足细胞轴抑制足细胞的增殖,并诱导足细胞分泌TNF-α水平增加。
文摘The plasma membrane vesicles were purified from soybean (Glycine max L.) hypocotyls by two_phase partitioning methods. The stimulatory effects of K + on the coupling between ATP hydrolysis and proton transport by the plasma membrane H +_ATPase were studied. The results showed that the proton transport activity was increased by 850% in the presence of 100 mmol/L KCl, while ATP hydrolytic activity was only increased by 28.2%. Kinetic studies showed that K m of ATP hydrolysis decreased from 1.14 to 0.7 mmol/L, while V max of ATP hydrolysis increased from 285.7 to 344.8 nmol Pi·mg -1 protein·min -1 in the presence of KCl. Experiments showed that the optimum pH was 6.5 and 6.0 in the presence and absence of KCl, respectively. Further studies revealed that K + could promote the inhibitory effects of hydroxylamines and vanadates on the ATP hydrolytic activity. The above results suggested that K + could regulate the coupling between ATP hydrolysis and proton transport of the plasma membrane H +_ATPase through modulating the structure and function of the kinase and phosphatase domains of the plasma membrane H +_ATPase.
文摘The stimulatory effect of lysophosphatidylcholine (lyso_PC) on ATP and ρ_nitrophenyl phosphate (PNPP) hydrolysis by the plasma membrane H +_ATPase from soybean (Glycine max (L.) Merr.) hypocotyls was studied. Results showed that lyso_PC stimulated the hydrolysis of ATP; ATP hydrolysis was enhanced dramatically when lyso_PC was within 0-0.03%, and increased slightly when lyso_PC was higher than 0.03%. At the concentration of 0.03%, lyso_PC stimulated ATP hydrolysis by 80.5%. Kinetics analysis showed that V max increased from 0.46 μmol P i·mg -1 protein·min -1 to 0.87 μmol P i·mg -1 protein·min -1 while K m increased from 0.88 mmol/L to 1.15 mmol/L under lyso_PC treatment. The optimum pH of ATP hydrolysis was shifted from 6.5 to 7.0 . Moreover, it was found lyso_PC enhanced the inhibition of ATP hydrolysis by hydroxylamine. In the presence of 200 mmol/L hydroxylamine, ATP hydrolysis was inhibited by 74.4%, while it was inhibited by 84.4% when treated with lyso_PC. However, PNPP hydrolysis and the inhibitory effect of vanadate were not affected by lyso_PC. The above results indicated that the kinase domain might be an action site or regulatory region of the C_terminal autoinhibitory domain in the plant plasma membrane H +_ATPase.
文摘ZnO films with c -axis parallel to the substrate are reported.ZnO films are synthesized by solid-source chemical vapor deposition,a novel CVD technique,using zinc acetate dihydrate (solid) as the source material.The properties are characterized by X-ray diffraction,atomic force microscopy and transmission spectra.The parallel oriented ZnO films with mixed orientation for (100) and (110) planes are achieved on glass at the substrate temperature of 200℃ and the source temperature of 280℃,and a qualitative explanation is given for the forming of the mixed orientation.AFM images show that the surface is somewhat rough for the parallel oriented ZnO films.The transmission spectrum exhibits a high transmittance of about 85% in the visible region and shows an optical band gap about 3.25eV at room temperature.
