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Zr-Y modified silicide coating was deposited on TC4 alloy by the pack cementation process. The microstructure， friction and wear performance， and wear mechanisms of the coating were investigated. The results show that the Zr-Y modified silicide coating has a multi-layer structure， an outer layer consists of TiSi2 and a small amount of ZrSi2， a thin middle layer is TiSi， and an inner layer is a mixture of Ti5Si4 and Ti5Si3. The micro-hardness of the coating is much higher than that of the TC4 substrate and exhibits an obvious decrease tendency from the surface to the interior. The Zr-Y modified silicide coating possesses good anti-wear performance when wearing against GCr15 and Al2O3 balls at a high-temperature of 600 ℃. When wearing against GCr15， the wear rate of the coating is about 3.59×10-5 mm3/（N·m）， which is about 36.6% of that of the TC4 substrate， and the main wear mechanisms are characterized by the adhesive of GCr15 on the coating surface and oxidation wear. When wearing against the Al2O3 ball， the wear rate of the coating is about 9.75×10-5 mm3/（N·m）， which is about 18.9% of that of the TC4 substrate， and the wear mechanisms are fatigue wear， oxidation wear， and adhesion wear.

This study aims to investigate the effects of five plant polysaccharides from Radix Astragalus, Rhizoma Atractylodis, Radix Scrophulariae, jujubes, Fructus mume on intestinal microorganisms and their metabolites in patients with type 2 diabetes mellitus (T2DM) by using high-throughput sequencing, metabolomic techniques and an in vitro fermentation model. The results showed that plant polysaccharides could significantly improve the structure of the intestinal flora in diabetic patients, and all five polysaccharides could enrich Faecalibacterium and Roseburia and inhibit Escherichia. Plant polysaccharides could regulate the contents of gas medium and short-chain fatty acids, and change the metabolic pathways of amino acids and short-chain fatty acids in the intestinal flora of patients with T2DM. Radix Astragalus, Atractylodis Rhizoma and Radix Scrophularia polysaccharides had significant regulatory effects on the total amount of short-chain fatty acids, and could also regulate the contents of acetic acid, propionic acid, butyric acid, valeric acid, isobutyric acid and isovaleric acid. In addition to these polysaccharides, jujube polysaccharide also increased the content of total gaseous media as well as CO2 and CH4 in patients with T2DM, while Fructus mume polysaccharide could reduce the contents of gas medium and H2S. These results provide a theoretical basis for the screening and utilization of plant polysaccharides and understanding their targeted regulation of intestinal microorganisms.

In order to synthesize a peptide-based carbonic anhydrase IX (CA IX) imaging probe 68Ga-DOTA-CA IX-P1-4-10, the labeling and quality control methods were developed. The effects of reaction pH and concentration of the peptide DOTA-CA IX-P1-4-10 on the labeling yield were studied. The reaction conditions were confirmed as: pH value 4.0 to 5.0 (n=6), peptide DOTA-CA IX-P1-4-10 concentration 15.0 to 40.0 mg/L (n=6), reaction temperature 100 ℃, and reaction time 10 min. The product was clear, colorless liquid, with no visible particles. The pH of the product was 5 to 7 (n=6), the radiochemical purity of 68Ga-DOTA-CA IX-P1-4-10 was >99.0% (n=6), and the specific activity of 68Ga-DOTA-CA IX-P1-4-10 was 1.0-5.0 GBq/μmol (end of synthesis) (n=6). The lipid-water partition coefficient of the probe was -2.07±0.01 (n=6) which indicated 68Ga-DOTA-CA IX-P1-4-10 was favorable hydrophilicity. 68Ga-DOTA-CA IX-P1-4-10 showed good in vitro stability in saline and fetal bovine serum at 37 ℃, and the radiochemical purity was >95.0% after 4 hours. White mice did not have abnormal behaviors in undue toxicity experiments. Preliminary results of the study showed that the probe 68Ga-DOTA-CA IX-P1-4-10 is worthy of further study with a simple labeling method, high radiochemical purity, good in vitro stability and favorable biosecurity.

Objective: To clarify the molecular signaling mechanism underlying the inhibitory effect of metformin on transforming growth factor-β1 (TGF-β1)-stimulated collagen I production in rat biliary fibroblasts., Methods: Primary biliary fibroblasts were isolated under aseptic condition from 50 Sprague-Dawley rats (half male and half female), and microscopic observation identified no obvious difference in the morphology or viability of the cells from rats with different sexes or body weight. The cells were treated with TGF-β1 (10 ng/mL), Smad3 siRNA+TGF-β1, CTGF siRNA+TGF-β1, metformin (10 mmol/L)+ TGF-β1, or Compound C (10 μmol/L)+metformin+TGF-β1. The expressions of CTGF and collagen I in the treated cells were determined using ELISA kit or Western blotting; the phorsphorylated and total Smad3 and AMPK expressions were detected using immunoblotting., Results: TGF-β1 time- and dose-dependently induced collagen I production in rat biliary fibroblasts. The activated AMPK by metformin dose-dependently inhibited TGF-β1-induced collagen I production. Pre-incubation of cells with the AMPK inhibitor Compound C restored the inhibitory effect of AMPK on TGF-β1-induced collagen I secretion ( P < 0.01). Activation of AMPK by metformin significantly reduced TGF-β1-induced collagen I production by suppressing Smad3-driven CTGF expression ( P < 0.01), and the application of Compound C reversed such changes in the fibroblasts ( P < 0.01)., Conclusions: Metformin inhibits TGF-β1-stimulated collagen I production by activating AMPK and inhibiting Smad3- driven CTGF expression in rat biliary fibroblasts.