Hierarchical CO2-protective shell for highly efficient oxygen reduction reaction

The widespread application of intermediate-temperature solid oxide fuel cells is mainly being hurdled by the cathode's low efficiency on oxygen reduction reaction and poor resistance to carbon dioxide impurity. Here we report the fabrication of a hierarchical shell-covered porous cathode through infiltration followed by microwave plasma treatment. The hierarchical shell consists of a dense thin-film substrate with cones on the top of the substrate, leading to a three-dimensional (3D) heterostructured electrode. The shell allows the cathode working stably in CO2-containing air, and significantly improving the cathode's oxygen reduction reactivity with an area specific resistance of ∼0.13 Ωcm2 at 575°C. The method is also suitable for fabricating functional shell on the irregularly shaped substrate in various applications

Alisertib, an Aurora kinase A inhibitor, induces apoptosis and autophagy but inhibits epithelial to mesenchymal transition in human epithelial ovarian cancer cells.

Ovarian cancer is a leading killer of women, and no cure for advanced ovarian cancer is available. Alisertib (ALS), a selective Aurora kinase A (AURKA) inhibitor, has shown potent anticancer effects, and is under clinical investigation for the treatment of advanced solid tumor and hematologic malignancies. However, the role of ALS in the treatment of ovarian cancer remains unclear. This study investigated the effects of ALS on cell growth, apoptosis, autophagy, and epithelial to mesenchymal transition (EMT), and the underlying mechanisms in human epithelial ovarian cancer SKOV3 and OVCAR4 cells. Our docking study showed that ALS, MLN8054, and VX-680 preferentially bound to AURKA over AURKB via hydrogen bond formation, charge interaction, and π-π stacking. ALS had potent growth-inhibitory, proapoptotic, proautophagic, and EMT-inhibitory effects on SKOV3 and OVCAR4 cells. ALS arrested SKOV3 and OVCAR4 cells in G2/M phase and induced mitochondria-mediated apoptosis and autophagy in both SKOV3 and OVCAR4 cell lines in a concentration-dependent manner. ALS suppressed phosphatidylinositol 3-kinase/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and p38 mitogen-activated protein kinase pathways but activated 5\u27-AMP-dependent kinase, as indicated by their altered phosphorylation, contributing to the proautophagic activity of ALS. Modulation of autophagy altered basal and ALS-induced apoptosis in SKOV3 and OVCAR4 cells. Further, ALS suppressed the EMT-like phenotype in both cell lines by restoring the balance between E-cadherin and N-cadherin. ALS downregulated sirtuin 1 and pre-B cell colony enhancing factor (PBEF/visfatin) expression levels and inhibited phosphorylation of AURKA in both cell lines. These findings indicate that ALS blocks the cell cycle by G2/M phase arrest and promotes cellular apoptosis and autophagy, but inhibits EMT via phosphatidylinositol 3-kinase/Akt/mTOR-mediated and sirtuin 1-mediated pathways in human epithelial ovarian cancer cells. Further studies are warranted to validate the efficacy and safety of ALS in the treatment of ovarian cancer

Effect of laser remelting on microstructure and properties of WC reinforced Fe-based amorphous composite coatings by laser cladding

The WC reinforced Fe-based amorphous composite coatings were prepared by laser cladding with rectangular spot. The effect of laser remelting on the microstructure and properties of composite coatings was investigated. The results showed that laser remelting can reduce the cracks and porosities of the cladding coating and improve its surface quality. Large amounts of crystalline phases were precipitated at the top of the cladding and remelting coatings. However, the microstructure at the top of the remelting coating was finer compared to that at the top of the cladding coating. With increasing distance from the surface of substrate, the amorphous phase appeared within the remelting coating and large amounts of carbides rich in Fe and Mo, Fe23B6, gamma-Fe and Cr-9.1.Si-0.9 Slag phases were also precipitated in the remelting coating. As a result, the corrosion resistance of the remelting coating was higher than that of the cladding coating. The microhardness of the remelting coating was approximately 1.13 times higher than that of the cladding coating. (C) 2018 Elsevier Ltd. All rights reserved

Giant Persistent Photoconductivity of the WO3 Nanowires in Vacuum Condition

A giant persistent photoconductivity (PPC) phenomenon has been observed in vacuum condition based on a single WO3 nanowire and presents some interesting results in the experiments. With the decay time lasting for 1 × 104 s, no obvious current change can be found in vacuum, and a decreasing current can be only observed in air condition. When the WO3 nanowires were coated with 200 nm SiO2 layer, the photoresponse almost disappeared. And the high bias and high electric field effect could not reduce the current in vacuum condition. These results show that the photoconductivity of WO3 nanowires is mainly related to the oxygen adsorption and desorption, and the semiconductor photoconductivity properties are very weak. The giant PPC effect in vacuum condition was caused by the absence of oxygen molecular. And the thermal effect combining with oxygen re-adsorption can reduce the intensity of PPC

Transcriptional activation of ENPP1 by osterix in osteoblasts and osteocytes

Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) is the main source of extracellular pyrophosphate. Along with tissue-nonspecific alkaline phosphatase (TNAP), ENPP1 plays an important role in balancing bone mineralisation. Although well established in pre-osteoblasts, the regulating mechanisms of ENPP1 in osteoblasts and osteocytes remain largely unknown. Using bioinformatic methods, osterix (Osx), an essential transcription factor in osteoblast differentiation and osteocyte function, was found to have five predicted binding sites on the ENPP1 promoter. ENPP1 and Osx showed a similar expression profile both in vitro and in vivo. Over-expression of Osx in MC3T3-E1 and MLO-Y4 cells significantly up-regulated the expression of ENPP1 (p < 0.05). The consensus Sp1 sequences, located in the proximal ENPP1 promoter, were identified as Osx-regulating sites using promoter truncation experiments and chromatin immunoprecipitation (ChIP) assays. The p38-mitogen-activated protein kinase (MAPK) signalling pathway was demonstrated to be responsible for ENPP1 promoter activation by Osx. Runt-related transcription factor 2 (Runx2) was confirmed to have synergistic effects with Osx in activating ENPP1 promoter. Taken together, these results provided evidence of the regulating mechanisms of ENPP1 transcription in osteoblasts and osteocytes

Marine Collagen Peptides Reduce Endothelial Cell Injury In Diabetic Rats By Inhibiting Apoptosis And The Expression Of Coupling Factor 6 And Microparticles

The present study aimed to elucidate the role of marine collagen peptides (MCPs) in protection of carotid artery vascular endothelial cells (CAVECs) in type 2 diabetes mellitus (T2DM), and the mechanism underlying this process. In an in vivo experiment, diabetic Wistar rats were divided randomly into four groups (n=10/group): Diabetes control, and three diabetes groups administered low, medium and high doses of MCPs (2.25, 4.5 and 9.0 g/kg body weight/day, respectively). Another 10 healthy rats served as the control. In an in vitro experiment, human umbilical‑vein endothelial cells (HUVECs) were incubated in normal and high concentrations of glucose with or without MCPs (3.0, 15.0 and 30.0 mg/ml, respectively) for 24, 48 or 72 h. Blood vessel/endothelial construction, inflammatory exudation and associated molecular biomarkers in CAVECs were detected and analyzed. The results of the present study demonstrated that in rats, MCP treatment for 4 weeks significantly lowered blood glucose and attenuated endothelial thinning and inflammatory exudation in carotid‑artery vascular endothelial cells. In vitro, the high‑glucose intervention significantly increased cell apoptosis in HUVECs, and medium and high doses of MCPs (4.5 and 9.0 g/kg body weight/day, respectively) partially ameliorated this high glucose‑mediated apoptosis and decreased levels of apoptosis biomarkers. In conclusion, a moderate oral MCP dose (≥4.5 g/kg body weight/day) may be a novel therapeutic tool to protect against early cardiovascular complications associated with T2DM by inhibiting apoptosis and reducing the expression of coupling factor 6 and microparticles. Key words: marine collagen peptide, coupling factor 6, microparticles, cell apoptosis, type 2 diabetes mellitus, cardiovascular complication

Introgression of Chromosome 3Ns from Psathyrostachys huashanica into Wheat Specifying Resistance to Stripe Rust

Wheat stripe rust is a destructive disease in the cool and humid wheat-growing areas of the world. Finding diverse sources of stripe rust resistance is critical for increasing genetic diversity of resistance for wheat breeding programs. Stripe rust resistance was identified in the alien species Psathyrostachys huashanica, and a wheat- P. huashanica amphiploid line (PHW-SA) with stripe rust resistance was reported previously. In this study, a P. huashanica 3Ns monosomic addition line (PW11) with superior resistance to stripe rust was developed, which was derived from the cross between PHW-SA and wheat J-11. We evaluated the alien introgressions PW11-2, PW11-5 and PW11-8 which were derived from line PW11 for reaction to new Pst race CYR32, and used molecular and cytogenetic tools to characterize these lines. The introgressions were remarkably resistant to CYR32, suggesting that the resistance to stripe rust of the introgressions thus was controlled by gene(s) located on P. huashanica chromosome 3Ns. All derived lines were cytologically stable in term of meiotic chromosome behavior. Two 3Ns chromosomes of P. huashanica were detected in the disomic addition line PW11-2. Chromosomes 1B of substitution line PW11-5 had been replaced by a pair of P. huashanica 3Ns chromosomes. In PW11-8, a small terminal segment from P. huashanica chromosome arm 3NsS was translocated to the terminal region of wheat chromosomes 3BL. Thus, this translocated chromosome is designated T3BL-3NsS. These conclusions were further confirmed by SSR analyses. Two 3Ns-specific markers Xgwm181 and Xgwm161 will be useful to rapidly identify and trace the translocated fragments. These introgressions, which had significant characteristics of resistance to stripe rust, could be utilized as novel germplasms for wheat breeding