In the present study it was proved first that human recombinant interleukin-6(HrIL-6) significantly augmented natural killer(NK) cell activity derived from human fetal spleens against K562 target cells in a 4 hours 51...In the present study it was proved first that human recombinant interleukin-6(HrIL-6) significantly augmented natural killer(NK) cell activity derived from human fetal spleens against K562 target cells in a 4 hours 51Cr release assay. The enhancement of NK activity with 24 hours preincubation in HrlL-6 was dose-dependent, and significantly higher than that of fresh NK cells and controls cultured with RPMI-1640 medium alone (P<0.001). We also found that IL-6 was able to augment NK activity from different fetal spleens at 20 to 40 weeks of gestation (up to 2.24 to 2.78 times), and no difference of NK activity of fetal splenocytes treated by HrIL-6 was observed between different fetal age (32.3% to 45.4%, P>0.05). Furthermore, IL-6-augmented NK activity of fetal splenocytes was very similar to adult levels (P>0.05). These finding strongly indicated that IL-6 plays an important role in the development of NK cell function during the gestational period, suggesting that IL-6 may be of importance in the regulation of host defense mechanisms against malignancies and viral diseases.展开更多
To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites ...To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites of prokaryotic expression vector pRSET containing T7 promoter.The recombinant plasmid pRSETAN was subsequently transformed into the strain E.coli BL21(DE3),and the target gene was expressed under induction of IPTG.The expressed protein was extracted,purified by Ni 2+ chelation affinity chromatography and refoled.The effect of the recombinant protein on proliferation of human umbilical vein endothelial cells (HUVECs) was also analyzed with the MTT assay.Results Endonuclease digesting and DNA sequencing confirmed that the arresten gene was correctly inserted into the expression vector.The recombinant protein was hightly expressed in the form of inclusion body in the host bacteria after induction.SDS-PAGE analysis revealed that the recombinant protein with a molecular weight of 26×103 amounted to 27% of the total bacterial proteins.The purity of the expected protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could significantly suppress proliferation of human umbilical vein endothelia cells(HUVECs) induced by vascular endothelial growth factor(VEGF).Conclusion Human arresten gene was successfully cloned into the expression vector pRSET and expressed at high level in Escherichia coli.Purified and refolded arresten protein could effectively inhibit proliferation of vascular endothelia cells.2 refs.展开更多
ZnO nanorods are passivated with a TiO2 interracial layer and applied in the CH3NH3PbI3 perovskite solar cell, which prepared by the atomic layer deposition method show a positive effect on the tiff factor and power c...ZnO nanorods are passivated with a TiO2 interracial layer and applied in the CH3NH3PbI3 perovskite solar cell, which prepared by the atomic layer deposition method show a positive effect on the tiff factor and power conversion efficiency. With TiO2 interracial passivation, the charge recombination in the ZnO/CH3NH3PbI3 interface is effectively suppressed and the maximum power conversion efficiency is enhanced from 11.9% to 13.4%.展开更多
In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficien...In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency PSCs.展开更多
This work was funded from National Natural Science Foun-dation of China(No.39770335 and No.30070327)andChongqing Medical Key construction Foundation.Abstract:Ob-jective To establish the experimental foundation for fur...This work was funded from National Natural Science Foun-dation of China(No.39770335 and No.30070327)andChongqing Medical Key construction Foundation.Abstract:Ob-jective To establish the experimental foundation for furtherstudying the effect of VCAM-1 gene modified HUCBSCs展开更多
Background Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes （RAG） and RAG-mediated V（D）J recombination. This process is named re...Background Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes （RAG） and RAG-mediated V（D）J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether the receptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkat human T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of T cell receptor （TCR） gene recombination. Methods TCR Dβ-Jβ signal joint T cell receptor excision DNA circles （sjTRECs） were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences （RSSs） in the TCRVβ chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 （CDR3） size of the TCRVβ chain was examined by the TCR GeneScan technique. Results RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining （NHEJ） pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dβ2-Jβ2 signal joints and ds RSS breaks associated with the Dβ2 5＇ and Dβ 2 3＇ sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVβ chain did not change during cell proliferation. Conclusions RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire.However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V（D）J recombination and as a ＂special＂ model of the coexistence of TCR gene rearrangements and ＂negative＂ receptor revision.展开更多
文摘In the present study it was proved first that human recombinant interleukin-6(HrIL-6) significantly augmented natural killer(NK) cell activity derived from human fetal spleens against K562 target cells in a 4 hours 51Cr release assay. The enhancement of NK activity with 24 hours preincubation in HrlL-6 was dose-dependent, and significantly higher than that of fresh NK cells and controls cultured with RPMI-1640 medium alone (P<0.001). We also found that IL-6 was able to augment NK activity from different fetal spleens at 20 to 40 weeks of gestation (up to 2.24 to 2.78 times), and no difference of NK activity of fetal splenocytes treated by HrIL-6 was observed between different fetal age (32.3% to 45.4%, P>0.05). Furthermore, IL-6-augmented NK activity of fetal splenocytes was very similar to adult levels (P>0.05). These finding strongly indicated that IL-6 plays an important role in the development of NK cell function during the gestational period, suggesting that IL-6 may be of importance in the regulation of host defense mechanisms against malignancies and viral diseases.
文摘To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites of prokaryotic expression vector pRSET containing T7 promoter.The recombinant plasmid pRSETAN was subsequently transformed into the strain E.coli BL21(DE3),and the target gene was expressed under induction of IPTG.The expressed protein was extracted,purified by Ni 2+ chelation affinity chromatography and refoled.The effect of the recombinant protein on proliferation of human umbilical vein endothelial cells (HUVECs) was also analyzed with the MTT assay.Results Endonuclease digesting and DNA sequencing confirmed that the arresten gene was correctly inserted into the expression vector.The recombinant protein was hightly expressed in the form of inclusion body in the host bacteria after induction.SDS-PAGE analysis revealed that the recombinant protein with a molecular weight of 26×103 amounted to 27% of the total bacterial proteins.The purity of the expected protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could significantly suppress proliferation of human umbilical vein endothelia cells(HUVECs) induced by vascular endothelial growth factor(VEGF).Conclusion Human arresten gene was successfully cloned into the expression vector pRSET and expressed at high level in Escherichia coli.Purified and refolded arresten protein could effectively inhibit proliferation of vascular endothelia cells.2 refs.
基金Supported by the National Key Basic Research Program of China under Grant Nos 2012CB932903 and 2012CB932904the Beijing Science and Technology Committee under Grant No Z131100006013003+1 种基金the National Natural Science Foundation of China under Grant Nos 51372270,51372272,21173260,11474333,91433205,51421002 and 91233202the Knowledge Innovation Program of Chinese Academy of Sciences
文摘ZnO nanorods are passivated with a TiO2 interracial layer and applied in the CH3NH3PbI3 perovskite solar cell, which prepared by the atomic layer deposition method show a positive effect on the tiff factor and power conversion efficiency. With TiO2 interracial passivation, the charge recombination in the ZnO/CH3NH3PbI3 interface is effectively suppressed and the maximum power conversion efficiency is enhanced from 11.9% to 13.4%.
基金financial support from the Natural Science Foundation of China (grant numbers: 51661135021, 21606039, 91233201, and 21276044)
文摘In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency PSCs.
文摘This work was funded from National Natural Science Foun-dation of China(No.39770335 and No.30070327)andChongqing Medical Key construction Foundation.Abstract:Ob-jective To establish the experimental foundation for furtherstudying the effect of VCAM-1 gene modified HUCBSCs
基金grants from Major State Basic Research Development 973 Program of China(No.2001CB510008 and 2003CB514113)NSFC & Research Grant Coancil of Hong Kong Joint Research Fund(No.30418003).
文摘Background Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes （RAG） and RAG-mediated V（D）J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether the receptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkat human T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of T cell receptor （TCR） gene recombination. Methods TCR Dβ-Jβ signal joint T cell receptor excision DNA circles （sjTRECs） were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences （RSSs） in the TCRVβ chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 （CDR3） size of the TCRVβ chain was examined by the TCR GeneScan technique. Results RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining （NHEJ） pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dβ2-Jβ2 signal joints and ds RSS breaks associated with the Dβ2 5＇ and Dβ 2 3＇ sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVβ chain did not change during cell proliferation. Conclusions RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire.However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V（D）J recombination and as a ＂special＂ model of the coexistence of TCR gene rearrangements and ＂negative＂ receptor revision.
