Objective:To prepare nanosilver-hybridized polylactic acid-glycolic acid copolymer (PLGA) microspheres loaded with simvastatin (SIM), and to evaluate its sustained release effect in vitro. Methods:The emulsification-solvent evaporation method was used to prepare SIM-loaded PLGA microspheres. Silk fibroin (SF) was used to modify the surface of SIM-loaded PLGA microspheres by hydrophobic interaction. Then, the microspheres were continually modified by electrostatic adsorption to chitosan (CTS) and nano-silver (AgNPs) to prepare SF-AgNPs-CTS-SF-SIM-PLGA microspheres. Scanning electron microscope, Fourier transform infrared spectrometer, energy spectrometer, Zeta potential meter were used to analyze the SIM-loaded microspheres. The external release properties of the SIM-loaded microspheres were also investigated.Results:The average diameter of the prepared PLGA microspheres was about 9.67 μm. The results of Fourier transform infrared spectroscopy and energy spectroscopy showed that the AgNPs-CTS-SF-SIM-PLGA microspheres have been successfully constructed. The Zeta potential results indicated that the SIM-loaded microspheres were all in a stable state. The in vitro release results showed that the SF-AgNPs-CTS-SF-SIM-PLGA microspheres had a good in vitro release effect, could delay the drug release rate and prolong the drug release time. Conclusions:The SF-AgNPs-CTS-SF-SIM-PLGA microspheres have antibacterial and osteogenic effects, and exhibit a good in vitro release effect. They can be used for local sustained-release administration in the oral cavity, which make makes them potentially useful in the treatment of periodontitis.

Objective To investigate the relationship between pulmonary arterial ( PA) enlargement and pulmonary function in patients with chronic obstructive pulmonary disease (COPD).Methods From December 2012 to June 2016,78 patients with acute exacerbation of COPD in the Eighth People＇s Hospital of Qingdao were selected. According to pulmonary CT findings,they were divided into two groups : PA enlargement group (38 cases) was PA＞3.0cm,normal PA group(40 cases) was PA≤3.0cm.FEV1and FVC of stable phase were compared.Results The FEV1of men in the A enlargement group was (1.08 ±0.44)L,that in the normal PA group was (1.44 ±0.66)L,the difference was statistically significant (t＝2.27,P＝0.028).The FEV1of women in the PA enlargement group was (0.90 ±0.41)L,which in the normal PA group was (1.35 ±0.58)L,the difference was statistically significant (t＝2.28,P＝0.026).Correlation analysis showed that the diameter of PA was negatively related with FEV 1/FVC(r＝-0.509,P＝0.001),PA enlargement was related with lung function decline.Conclusion COPD patients with PA enlargement are more associated with accelerated loss of lung function and should be treated early.