A new and convenient sonoelectrochemical method was used to synthesize uniform three-dimensional (3D) dendritic Pt nanostructures (DPNs) at room temperature. The size and morphology of the final product could be controlled via simply adjusting the experiment parameters. The morphology and structure of the DPNs were characterized by transmission electron microscopy, high resolution transmission electron microscopy, field emission scanning electron microscopy, energy-dispersive X-ray, and X-ray diffraction. The formation process of the DPNs was carefully studied, and a spontaneous assembly mechanism was proposed based on the experimental results. Additionally, the electrocatalytic activity of the DPNs was evaluated using methanol and glucose as model molecules. The DPNs showed improved electrocatalytic activity toward methanol oxidation with respect to the monodisperse Pt nanoparticles; this improvement is due to the porosity structure and the greatly enhanced effective surface area. In addition, a sensitive enzyme-free biosensor can be easily developed for the detection of glucose in pH 7.4 phosphate buffer solution. The present method provides a new and simple strategy toward the fabrication of 3D DPNs with extensive applications.

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A detailed investigation of the absorption and CD signals of Ag(I)-cysteine (Cys) aqueous solutions at buffered or varying pH has allowed us to suggest that coordination polymers are formed upon mixing Ag(I) and Cys bearing a Ag(I)-Cys repeat unit. The formation of the coordination polymers are shown to be facilitated by both the Ag(I)···Ag(I) interaction and the interaction between the side chains in the polymeric backbone. The former allows for an immediate spectral sensing of Cys with enantiomeric discrimination capacity with both high sensitivity and selectivity, and the contribution of the side-chain/side-chain interaction serves to guide extended sensing applications by means of modulating this interaction. With our preliminary data on the corresponding Cu(I)-Cys and Au(I)-Cys systems that exhibited similar spectral signals, we conclude that the M(I)-SR coordination polymers (M = Cu, Ag, or Au) could in general function as spectral sensing ensembles for extended applications. This sensing ensemble involves the formation of coordination polymers with practically no spectral background, thus affording high sensing sensitivity and selectivity.

BackgroundAberrant expression of lncRNA has been suggested to have an association with tumorigenesis. Our study was designed to reveal the underlying connection between lncRNA SNHG1 and hepatocellular carcinoma (HCC) pathogenesis.Material/MethodsA total of 122 pairs of HCC tissues (case group) and matched adjacent non-tumor liver tissues (control group) were collected for this study. RT-PCR and in situ hybridization were conducted to investigate differences in lncRNA SNHG1 expression between the case and control group. The expression levels of lncRNA SNHG1 and miR-195 in HepG2 cells transfected with SNHG1-mimic and SNHG1-inhibitor were measured by RT-PCR. The proliferation, invasion, and migration status of HepG2 cells after transfection were assessed through MTT assay, wound healing assay, and Transwell assay, respectively. Whether miR-195 is a direct downstream target of lncRNA SNHG1 was verified by both bioinformatics target gene prediction and dual-luciferase report assay.ResultsThe expression level of lncRNA SNHG1 was remarkably upregulated in HCC tissues and cell lines compared with normal tissues and cell lines. High expression of lncRNA SNHG1 contributed to the downregulation of miR-195 in HepG2 cells. Also, lncRNA SNHG1 exacerbated HCC cell proliferation, invasion, and migration in vitro through the inhibition of miR-195. This suggests that miR-195 is a direct downstream target of lncRNA SNHG1.ConclusionslncRNA SNHG1 may contribute to the aggravation of HCC through the inhibition of miR-195.

Ru NPs could catalyze the oxidation of 3,3,5,5-tetramethylbenzidine, o-phenylenediamine and dopamine hydrochloride in the presence of H2O2, and also catalyze the oxidization of 3,3,5,5-tetramethylbenzidine and sodium l-ascorbate by dissolved oxygen.

Extensive thoracic aorta repair of acute type I aortic dissection can be performed simply by combining ascending aorta and hemiarch replacement with modified triple-branched stent graft implantation. This technique can reduce the risk and technical difficulty of extensive thoracic aorta repair to levels close to those seen with ascending aorta and hemiarch graft replacement with open distal anastomosis.

This paper reports that iron carbide nanoparticles with high air-stability and strong saturation magnetization can serve as effective T2 contrast agents for magnetic resonance imaging. Fe5C2 nanoparticles (~20 nm in diameter) exhibit strong contrast enhancement with an r2 value of 283.2 mM(-1) S(-1), which is about twice as high as that of spherical Fe3O4 nanoparticles (~140.9 mM(-1) S(-1)). In vivo experiments demonstrate that Fe5C2 nanoparticles are able to produce much more significant MRI contrast enhancement than conventional Fe3O4 nanoparticles in living subjects, which holds great promise in biomedical applications.

Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core-shell structure of the monodisperse molecule magnet of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]@SiO2 (1 a@SiO2 ) was prepared by encapsulating one high-nuclearity lanthanide-transition-metal compound of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]⋅(NO3 )18 ⋅164 H2 O (1) (IDA=iminodiacetate) into one silica nanosphere through a facile one-pot microemulsion method. 1 a@SiO2 was characterized using transmission electron microscopy, N2 adsorption-desorption isotherms, and inductively coupled plasma-atomic emission spectrometry. Magnetic investigation of 1 and 1 a revealed J1 =0.25 cm(-1) , J2 =-0.060 cm(-1) , J3 =-0.22 cm(-1) , J4 =-8.63 cm(-1) , g=1.95, and z J=-2.0×10(-3)  cm(-1) for 1, and J1 =0.26 cm(-1) , J2 =-0.065 cm(-1) , J3 =-0.23 cm(-1) , J4 =-8.40 cm(-1)  g=1.99, and z J=0.000 cm(-1) for 1 a@SiO2 . The z J=0 in 1 a@SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres.