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991.
992.
Gene transfer of basic fibroblast growth factor (bFGF) has been shown to induce significant endothelial migration and angiogenesis in ischemic disease models. Here, we investigate what factors are secreted from skeletal muscle cells (SkMCs) transfected with bFGF gene and whether they participate in endothelial cell migration. We constructed replication-defective adenovirus vectors containing the human bFGF gene (Ad/bFGF) or a control LacZ gene (Ad/LacZ) and obtained conditioned media, bFGF-CM and LacZ-CM, from SkMCs infected by Ad/bFGF or Ad/LacZ, respectively. Cell migration significantly increased in HUVECs incubated with bFGF-CM compared to cells incubated with LacZ-CM. Interestingly, HUVEC migration in response to bFGF-CM was only partially blocked by the addition of bFGF-neutralizing antibody, suggesting that bFGF-CM contains other factors that stimulate endothelial cell migration. Several proteins, matrix metalloproteinase-1 (MMP-1), plasminogen activator inhibitor-1 (PAI-1), and cathepsin L, increased in bFGF-CM compared to LacZ-CM; based on 1-dimensional gel electrophoresis and mass spectrometry. Their increased mRNA and protein levels were confirmed by RT-PCR and immunoblot analysis. The recombinant human bFGF protein induced MMP-1, PAI-1, and cathepsin L expression in SkMCs. Endothelial cell migration was reduced in groups treated with bFGF-CM containing neutralizing antibodies against MMP-1 or PAI-1. In particular, HUVECs treated with bFGF-CM containing cell-impermeable cathepsin L inhibitor showed the most significant decrease in cell migration. Cathepsin L protein directly promotes endothelial cell migration through the JNK pathway. These results indicate that cathepsin L released from SkMCs transfected with the bFGF gene can promote endothelial cell migration.  相似文献   
993.
A new type of fluorescent probe (1) with two triazole groups that are conjugated with a carbazole moiety was synthesized by a Cu(I)-catalyzed alkyne-azide click reaction for the selective and sensitive detection of cyanide via fluorescence enhancement by ligand exchange and metal ion removal.  相似文献   
994.
Novel ZnO/TiO(2) composite nanofibers were fabricated by an electrospinning method and showed excellent antimicrobial activity against gram-negative Escherichia coli and gram-positive Staphylococcus aureus under UV irradiation and in the absence of light.  相似文献   
995.
Nitric oxide-releasing ruthenium nanoparticles were synthesized by the reaction of alkanethiolate-protected ruthenium nanoparticles with tert-butyl nitrite ((t)BuONO), and their water-soluble derivatives are able to deliver NO to proteins such as reduced myoglobin upon light irradiation in aqueous media.  相似文献   
996.
To simply reduce HAuCl(4) using 2-thiophenemethanol in an aqueous solution at room temperature, a novel metallic Au nanostructure with a high SERS activity was obtained. Flat sheet-like Au nanoleaves possessing many nanogap hotspots bound with a large percentage of high-index facets were obtained.  相似文献   
997.
In a free solution of 10.0 mM Gly-Gly (pH 8.2), the flow directions of native-DNA and DNA molecules intercalated with the fluorescent dye YOYO-1 were reversed in the microchip channel. These results clearly showed that in a confined space and under specific environmental conditions, the fluorescent dye modified the original properties and behavior of the native-DNA molecule.  相似文献   
998.
An intimate interplay of O-H···O/C-H···F hydrogen bonds and π-π stacking interactions allows a phenyleneethynylene-based dendritic molecule to fold and self-assemble into two distinctively different molecular crystals as pseudopolymorphs.  相似文献   
999.
An enzyme-magnetic nanoparticle conjugate is prepared via conjugation of Ni(2+) ions onto the surface of magnetic nanoparticles to interact with a six histidine-tagged enzyme. The catalytic properties and enzyme rigidification of the conjugates are more stable at high concentrations of aromatic hydrocarbons.  相似文献   
1000.
A three-dimensional extended, metal-organic rotaxane framework (MORF) that incorporates encircled "struts" has been synthesized through a one-pot self-assembly process involving a macrocyclic tetraimidazolium "molecular box", naphthalene dicaboxylate dianion, and Zn(II) cations. The present system represents progress towards controlling the features of three-dimensional metal-organic frameworks.  相似文献   
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