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Background: Maternal diabetes increases the risk for neural tube defects (NTDs). It is unclear if miRNAs, senescence, and DNA damage are involved in this process. In this study, we used neural stem cells as an in vitro proxy of embryonic neuroepithelium to investigate whether high glucose triggers neural stem cell senescence and DNA damage by upregulating miR‐200c, which may be responsible for NTDs. Methods: C17.2 neural stem cells were cultured with normal glucose (5 mM) or high glucose (≥16.7 mM) at different doses and time points for detecting miR‐200c levels, markers of senescence and DNA damage. Neural stem cells were exposed to antioxidant SOD1 mimetic Tempol and high glucose for 48 h to test roles of oxidative stress on the miR‐200c, senescence, and DNA damage levels. An miR‐200c mimic and an inhibitor were transfected into neural stem cells to increase or decrease miR‐200c activities. Results: High glucose upregulated miR‐200c in neural stem cells. A time course study of the effect of high glucose revealed that miR‐200c initially increased at 12 h and reached its zenith at 18 h. Tempol reduced miR‐200c levels caused by high glucose. High glucose induced markers of senescence and DNA damage in neural stem cells. Tempol abolished high glucose‐induced markers of senescence and DNA damage. The miR‐200c inhibitor suppressed high glucose‐induced markers of senescence and DNA damage. Treatment with miR‐200c mimic imitates high glucose‐induced markers of senescence and DNA damage. Conclusions: We show that high glucose increases miR‐200c, which contributes to cellular senescence and DNA damage in neural stem cells and provides a potential pathway for maternal diabetes‐induced neural tube defects. [ABSTRACT FROM AUTHOR]

Biomass‐derived carbon (BC) has attracted extensive attention as anode material for lithium ion batteries (LiBs) due to its natural hierarchical porous structure and rich heteroatoms that can adsorb Li+. However, the specific surface area of pure biomass carbon is generally small, so we can help NH3 and inorganic acid produced by urea decomposition to strip biomass, improve its specific surface area and enrich nitrogen elements. The nitrogen‐rich graphite flake obtained by the above treatment of hemp is named NGF. The product that has a high nitrogen content of 10.12% has a high specific surface area of 1151.1 m2 g−1. In the lithium ion battery test, the capacity of NGF is 806.6 mAh g−1 at 30 mA g−1, which is twice than that of BC. NGF also showed excellent performance that is 429.2 mAh g−1 under high current testing at 2000 mA g−1. The reaction process kinetics is analyzed and we found that the outstanding rate performance is attributed to the large‐scale capacitance control. In addition, the results of the constant current intermittent titration test indicate that the diffusion coefficient of NGF is greater than that of BC. This work proposes a simple method of nitrogen‐rich activated carbon, which has a significantly commercial prospect. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate and compare the surface characteristics and initial bioactivity of ceria-stabilized zirconia/alumina nanocomposite (NANOZR) with those of yttria-stabilized zirconia (3Y-TZP) and pure titanium (CpTi) following the use of three surface modification methods; polishing, sandblasting/acid-etching (SB-E) and electrochemical deoxidation (ECD). Physical properties including surface morphology, chemical composition, X-ray diffraction, surface wettability, surface roughness, and hardness were measured. Osteoblast-like MC3T3-E1 cells were used to examine cell morphology and attachment to the surfaces of the materials. ECD treated NANOZR (NANOZR-E) showed a well-arranged, self-organized microporous surface structure with significantly low contact angles when compared with the other specimens ( p < 0.05). NANOZR-E also demonstrated a slight decrease in monoclinic phase content (−4.4 wt %). The morphology and attachment of MC3T3-E1 cells on NANOZR-E were similar to those on polished and SBE-treated CpTi surfaces. Higher cell affinity was observed on NANOZR-E when compared with ECD treated 3Y-TZP. The findings of this study indicate the effectiveness of the novel technique, ECD, in the formation of a microporous surface on NANOZR when compared with both CpTi and 3Y-TZP. Moreover, this method also appears to improve the biological activity of NANOZR during the initial stage. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2641-2652, 2017. [ABSTRACT FROM AUTHOR]

In this study an analysis strategy towards using the resonant inelastic X-ray scattering (RIXS) technique more effectively compared with X-ray absorption spectroscopy (XAS) is presented. In particular, the question of when RIXS brings extra information compared with XAS is addressed. To answer this question the RIXS plane is analysed using two models: (i) an exciton model and (ii) a continuum model. The continuum model describes the dipole pre-edge excitations while the exciton model describes the quadrupole excitations. Applying our approach to the experimental 1 s2 p RIXS planes of VO2 and TiO2, it is shown that only in the case of quadrupole excitations being present is additional information gained by RIXS compared with XAS. Combining this knowledge with methods to calculate the dipole contribution in XAS measurements gives scientists the opportunity to plan more effective experiments. [ABSTRACT FROM AUTHOR]