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The effects of titanium dioxide (TiO2) nanoparticles on the intestinal microbiome and fecal metabolome in C57BL/6 mice were investigated and the correlation between the intestinal microbiome and fecal metabolome was analyzed. A control group and an experimental group were set up, which were orally administered with phosphate buffered saline (PBS) and 100 (mg/kg mb·d) of TiO2 nanoparticles for 13 continuous weeks, respectively. Blood glucose and lipids were measured. Furthermore, 16S rDNA gene sequencing and gas chromatography-mass chromatography (GC-MS) were used to identified the significantly differential microorganisms and metabolites between the two groups. Our results showed that compared with the control group, fasting blood glucose was significantly increased in the experimental group (P = 0.032). The relative abundance of Firmicutes, Allobaculum, Lactobacillus, and Oscillospira was increased. The differential metabolites were associated with the glycerolipid, galactose and tryptophan metabolic pathways. Firmicutes bacteria were negatively correlated with the differential metabolites, while bacteria from other phyla were positively correlated with the differential metabolites. Therefore, we infer that the subchronic toxicity of TiO2 nanoparticles to mice may be associated with abnormal glycolipid metabolism in feces.

Objective To observe the effect of infiltration resin combined with cold light whitening in the treatment of dental fluorosis. Methods According to the distance between teeth and the long axis of each tooth, 18 anterior teeth were divided equally and randomly between group A and B. Samples in group A underwent cold light whitening, while samples in group B were treated with infiltration resin combined with cold light whitening. The color was measured before and after the treatment. Then, 6 teeth (the first subgroup) were randomly selected from the 18 anterior teeth after measurement for scanning electron microscopy (SEM) to observe the surface microstructure of the teeth. Then, another 6 teeth (the second subgroup) were selected from the remaining 12 teeth for the measurement of the color level and ΔE after being dyed with tea. Results After treatment, the color level changed significantly in group A and B (P < 0.05), ΔE in group A and B was 13.75, 14.98. There was no significant difference in the color level change between group B and group A, there was a significant difference in the ΔE between the two groups (t = ⁃3.58, P < 0.05). SEM showed that the enamel surface was intact and that the enamel space was filled in group B. In group A, the enamel surface was reduced and uneven, and the characteristic badminton racquet shape of the enamel was not obvious. The color level was lower in both groups after staining, and these differences were significant (P < 0.05), ΔE in group A and B was 19.69, 18.95. There was no significant difference in the color level (t = 1.00, P > 0.05) and ΔE (t = 0.02, P > 0.05) between two groups. Conclusion Cold light whitening combined with infiltration resin is better for treating dental fluorosis than cold light whitening alone.

To measure the systemic risk contribution of the financial institutes in China more accurately and to avoid financial risk events, a new method named CoES model is proposed based on the mean value of tail loss. Compared to the traditional CoVaR model, this method pays more attention to the mean value of tail loss than the expected loss on one single quantile, which could provide more accurate information for the supervision when capturing the systemic risk of financial system. The new method is utilized to measure the systemic risk contributions of 21 financial institutions in China from 2007 to 2016. The empirical results show that: 1) the CoVaR model may underestimate the systemic risk of financial institutes; 2) the banking industry brings the largest systemic risk contribution to the whole financial system, followed by insurance, real estate and diversified financial industry; 3) among banking industry, the systemic risk contributions of Industrial and Commercial Bank of China and Bank of China are the largest, which should be the key regulatory objects; 4) compared with the banking and real estate industry, the insurance industry and the diversified financial industry own higher VaR value and their systemic risk contributions are relatively lower, so the regulators could pay more attention to their own risk management. [ABSTRACT FROM AUTHOR]

The liposomes were prepared by reverse-phase evaporation technique. The morphology of the liposomes, the entrapment efficiency and the particle size distribution were evaluated. The CT signals of Iohexol liposomes in rabbits were compared with those of Iohexol injection in rabbits. The entrapment efficiency of Iohexol liposomes was 82.35% +/- 1.82%. The liposmes were spherical or ellipsoidal shape in shape. The mean diameter of the Iohexol liposomes was 207 7 nm. The polydispersity index was 0.355. The Zeta potential was--1.83 mV. The drug was highly entrapped into the liposomes with good reproduction and stability. The in vitro release of Iohexol liposomes was significantly slower than that of Iohexol,and was 98.57% at 24 h. Iohexol liposomes may reduce the dosage, prolong the effective time of the developing agent, and could reduce the side effects of Iohexol on the blood vessels and cerebral nerves.