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The mechanism of antler peptide (TL4 peptide), an active ingredient of deer antler, in promoting the proliferation and ALP content of osteoblasts in MC3T3-E mice was investigated by using nuclear magnetic resonance hydrogen spectroscopy (1HNMR)-based cellular metabolomics techniques. The proliferation rate of MC3T3-E mouse osteoblasts and the ALP content in the cell culture medium were measured before and after the administration of TL4 peptide, and the metabolites in the cell crushing medium of MC3T3-E mice were investigated with principal component analysis and orthogonal partial least squares discriminant analysis. The results showed that deer antler peptide (TL4 peptide) could increase the proliferation rate and ALP content of MC3T3-E mouse osteoblasts, and the metabolic profile of cell lysate of MC3T3-E mouse significantly changed after administration. Metaboanalyst analysis revealed that the differential metabolites were mainly related to Phenylalanine, tyrosine and try.ptophan biosynthesis, Taurine and hy. potaurine metabolism, Phenylalanine metabolism and Glycine, serine and threonine metabolism, etc. It was initially clarified that TL4 peptide promoted cell proliferation and ALP content in MC3T3-E mice by regulating the nodes of these metabolic pathways.

A rapid and simple method has been developed for the screening and identification of natural antioxidants from the leaves of Acer ginnala Maxim (AG). The process is that upon reaction with 1,1-diphenyl-2-picrylhydrazyl (DPPH), the white yellow spots of compounds with potential antioxidant effects will be significantly observed on the thin-layer chromatography (TLC), and possible structures will be presumed by the ESI/MS technique. Using the improved approach, 6 compounds in the AG extract were found to possess a potential antioxidant activity. They were speculated as quercetin-3-O-α-L-(3"-galloyl)-rhamnoside (1), quercetin-3-O-α-L-(2"-galloyl)-rhamnoside (2), quercetin-3-O-α-L-(2"-galloyl)-arabinopyranoside (3), acertannin (4), gallic acid (5), and methyl gallate (6). In addition, we were still found that compounds 2, 3, and 5 had favorable antioxidant activity from the scannogram of the DPPH reaction plate. As a result, the isolated 6 compounds structures were in accordance with the presumed structures. Furthermore, the free radical scavenging capacities of the available identified compounds were also investigated. Compounds 2, 3, and 5 showed significant DPPH.Scavenging capacities, with IC50 values of 2.83 μg/mL, 2.34 μg/mL, and 1.86μg/mL, respectively. The results indicated that this newly improved method could be widely applied for rapid screening and identification of natural antioxidants from Chinese herbal medicines.

Additional file 4: Table S1. Primers used for quantitative PCR.

Metal-oxide-semiconductor structure of ITO/Si-rich SiO2∶Er/Si containing erbium ions and silicon nanocrystals was fabricated by ion implantation of Si and Er combined with post-annealing.The electroluminescence spectra and current-voltage characteristics were measured to investigate the influence of silicon concentration on the excitation mechanism of luminescence centers and conductance process.It was found that the excitation mechanism of erbium ions was variational in the MOS-LED with silicon content.For the silicon concentration less than 5%,the upper levels of erbium can be excited by resonant energy transfer from silicon-oxygen deficiency centers,which induce an enhancement of the 522 nm peak emission intensity of Er3+ ion.For the silicon concentration above 5%,the excess silicon formed silicon nanocrystals by post-annealing.The direct tunneling of electrons between silicon nanocrystals dominate the conductance,resulting a decrease of average energy of hot electrons and quenching of all the electroluminescence peaks of erbium.

Amorphous Si/SiO2 superlattices have been deposited on glass substrates using two-target alternation magnetron sputtering technique. The samples are characterized using transmission electron microscope and low-angle X-ray reflectance techniques. The results indicate that most of the regions in Si layers consist of amorphous phase in the superlattices, while the regular structure appears in some local regions rarely. The thicknesses of Si layers are in a range from 18 to 3.2nm and the thickness of SiO2 layer is 4.0nm in all cases. The samples are systematically studied using absorption, photoluminescence (PL) and Raman spectroscopy techniques. The absorption edge positions and PL peaks shift towards shorter wavelengths while Raman spectra show broader peaks with decreasing Si layer thickness. The results are mainly attributed to the quantum confinement effects.