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Cell metabonomics focuses on discovering metabolic biomarkers and pathway changes in cells from biological systems to obtain the cell properties and functional information under different conditions. Baicalin possesses various pharmacological activities, and plays a vital role in the oncology research field. However, the detailed mechanism of its action is still unclear. In this work, we employed ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) based non-targeted metabolomics method associated with chemometrics analysis to explore metabolic pathways and biomarkers for investigating the efficacy and pharmacological targets of baicalin against thyroid cancer cells. In addition, morphological observation, parameter calculation of cell proliferation and apoptosis were carried out, which assisted in elucidation of pharmacological activity of baicalin on the human thyroid cancer cells. The results showed that baicalin possesses an intense stimulative apoptosis and inhibits proliferation activity on SW579 human thyroid cancer cells, and partially reversed the cell metabolite abnormalities. A total of nineteen differentiated metabolites in SW579 cells were identified and deemed as potential biomarkers after the baicalin treatment, involving nine metabolic pathways, such as taurine and hypotaurine metabolism, pyrimidine metabolism, fructose and mannose metabolism, steroid hormone biosynthesis and sphingolipid metabolism. High-throughput non-targeted metabolomics provide an insight into specialized mechanism of baicalin against thyroid cancer and contributes to novel drug discovery and thyroid cancer management in clinical practice.

Vegetative but not reproductive stage of Saposhnikovia divaricate (Turxz.) schischk possesses pharmacological activities. However, our recent study showed that reproductive S. divaricate supplemented with polysaccharide showed evidently elevated pharmacological activities and increased cimifugin content in rat serum. The aims of present study were to assess the influence of polysaccharides on the chromones pharmacological activities in Radix Saposhnikoviae (RS), the dried root of vegetative stage of S. divaricate, and to explore the underlying mechanisms. Only cimifugin was detected in the plasma of chromone treated animals and RS polysaccharide significantly increased the plasma content of cimifugin. It was shown that neither cimifugin absorption nor glycoside components transformation in simulated digestive fluid was affected by RS polysaccharide. However, a significant promotion of transformation of cimifugin to more stable prime-O-glucosylcimifugin (PGCN) by RS polysaccharide, and a protective effect of polysaccharide on chromone components were observed in small intestine solutions. Meanwhile, RS polysaccharide produced a significant elevation of cimifugin and PGCN concentration in vivo. Based on these findings, we concluded that RS polysaccharide could greatly increase the content of cimifugin, which might be related to its degradation-proof effect on cimifugin, via transforming cimifugin to comparatively more stable PGCN and spatial structure protection.

The excellent properties of Mg-Li alloys make them suitable light fabrication materials used extensively in many applications. The microstructure and the surface oxide film at different temperature of as-cast Mg-7Li alloy were investigated by optical microscope(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD) and electronic analytical balance. Results showed that Mg-7Li alloy was composed of mainly α phase and β phase. With increasing temperature, the morphology of the alloy surface varied from the formation of a very thin oxide film, large amounts of oxide particles to the thick and coarse film with a mass of cellular protuberances in size of 40-80μm. The ratio of oxidation weight gains rose from 0.08% to 11.58%. The surface oxide film consisted of mainly magnesium oxide(MgO) phase and lithium peroxide(Li2O2) phase, resulting from the reaction of oxygen with Mg and Li. The volume of the oxides on β phase greater than that on α phase led to the formation of cellular protuberance on the surface of Mg-7Li alloy at high temperature.

Chitosan fibers(CSf) andCaSiO3 were incorporated into a poly (L-lactic acid)/hydroxyapatite (PLLA/HA) matrix as reinforcements to prepare scaffold composites with adequate strength and high porosity for bone tissue engineering combined with emulsion freeze drying technique. The structural morphology of the composites was observed by scanning electron microscope (SEM). The porosity was tested by liquid substitute method. The mechanical property was measured. The effects of addition of CSf and CaSiO3 on composites were also discussed. Simulated body fluid (SBF) experiments were conducted to assess the bioactivity of the composites. The chemical components of resultants on surfaces after the immersion in SBF were analyzed by fourier transform infrared spectroscopy (FTIR). The results show that the composites with high connectivity have pore sizes of 100~250μm, a porosity of 60%~80%, compressive strength of 3.5~8.0MPa. In the SBF tests, Chitosan fiber reinforced PLLA/HA-CaSiO3 composite degraded stably, meanwhile, the formation of a layer of bone-like apatite on the surfaces of the samples indicated a good bioactivity. Studies suggest the feasibility of using CSf reinforced PLLA /HA-CaSiO3 composite for bone tissue engineering.

A composite of needle-like nano-Hydroxyapatite / silk fibroin (n-HA/SF) with strong interfacial bonding was successfully prepared from calcium chloride (CaCl2) and diammonium phosphate ((NH4)2HPO4) as starting materials of HA in the presence of SF powders dissolved in a ternary solvent system of CaCl2-C2H5OH-H2O (1:2:8 in molar ration) at 80 °C for 30 min prior to preparation of n-HA/SF composite. The n-HA crystals in the composite were poorly crystallized and uniformly distributed in the composite with a crystal size of 4~6 nm in diameter and 20~40 nm in length, which was smaller than that of pure nano-HA. Molecular interaction and strong chemical bonds were formed between n-HA and SF in the composite, which were revealed by Fourier transform infrared spectrometric analysis (FTIR). The synthetic n-HA/SF composite had a good homogeneity and preferential orientation along c-axis and would have a great potential for bone tissue engineering.

Porous composites composed of hydroxyapatite (HA), herb epimedium (EP), and chitosan (CS) were used to improve the repair of rabbit bone defects. The in vivo implantation of the HA/CS-EP showed that homogeneous bone formation occurred after 12 weeks' implantation and possessed good osteogenesis. The osteogenic process of the HA/CS-EP group was different from that of the HA/CS group. Direct bone formation of osteoblasts with HA/CS-EP as the matrix could be observed. Compared with the group filled with HA/CS, the group filled with HA/CS-EP showed significant increases in the number of osteoblasts and the bone formation area, and the areas of new bone formation in the HA/CS-EP group after 4 or 12 weeks' implantation reached 33% and 87%, respectively. The novel repair system of HA/CS-EP can induce bone formation, increase osteoblast quantity and improve osteogenesis, for EP can significantly promote the proliferation and activity of osteoblasts in the early stage and accelerate bone remodeling in the later stage. Composites containing EP could be a promising material with multifunctions of osteoinduction, osteoconduction and medication for bone repair, and herb medicine EP could be used as an osteoinduction material for bone tissue engineering.