Objective Our study was performed to design a drug-sustained capsular tension ring (CTR) to evaluate its potentiality on prevention of PCO in the swine capsular bag model in vitro.Methods Following the continuous capsule curvilinear capsulorhexis ( CCCC),Phacomulsification with capsular tension ring implantation was pedormed.CTR-supported swine capsular bag models were prepared and divided into two groups,group CTR ( n =13 ) implanted with the original CTR without any modification and group CTR-PLGA-MG132 ( n =13) implanted with the CTR covered with PLGA and MG132.The CTRsupported capsular bags were cultured in vitro for up to 3 weeks.The area of lens epithelial cells (LEC) coverage over the posterior capsule surface was quantified every day under microscope.The capsules were treated for histological examination.The change of fibronectin was assessed by ELISA assay kit.Results After 2 ～ 3 days,outgrowth of LEC across the posterior capsule was observed,and the posterior capsule was totally covered by a confluent monolayer of cell after (9.06 ± 1.61 ) days in group CTR.Capsular wrinkles became increasingly apparent as time progressed.An increase in capsular thickness was also observed.In contrast,there was less LEC deposition in group CTR-PLGA-MG132.Histological examination showed LEC layers were closely arranged on the posterior capsular surface in group CTR.In group CTR-PLGA-MG132,there was comparatively looser cell arrangement.Compared with group CTR,the mean fibronectin level of posterior capsule by week 3 in group CTR-PLGA-MG132 was 25.14 μg/ml and 106.09 μg/ml respectively.Statistical analysis showed a significant difference ( P ＜ 0.01 ).Conclusions LEC migration,proliferation,and synthesis of EMT markers were inhibited in Group CTR-PLGA-MG132,compared with Group CTR.Drug-sustained capsular tension rings can effectively inhibit the migration,proliferation of LEC and the change of EMT ( epithelial-to-mesenchymal transition) in swine capsular bag models.Drug-sustained capsular tension rings might be a potential therapy to prevent the posterior capsular opacification in the future.

In order to investigate the effects of porin genes ompW,ompS and ompD on the biological properties and virulence of Salmonella typhimurium,the corresponding mutant strains were con-structed using the λ Red homologous recombination system,and the growth curves,motility,bio-chemical properties,in vitro genetic stability,biofilm-forming ability,drug resistance,and lethal dose at half capacity(LD50)between the standard strain and each mutant strain were detected by comparative assays for Salmonella typhimurium.The results showed that,compared with the standard strain,the ompD and ompW mutation had less effect on the growth rate and motility of the bacteria,while the ompS mutation significantly reduced the growth rate and motility;none of the three genetic mutation affected the biochemical characteristics of Salmonella typhimurium,nor the genetic stability,but affected its susceptibility to a variety of commonly used antibiotics to varying degrees and caused a highly significant decrease(P＜0.01)in the ability to form a biofilm,and the results showed that the three mutant strains had a significant reduction in the ability to form a biofilm.The result of LD50 virulence assay showed that all three genetic mutation led to a decrease in the virulence of Salmonella typhimurium,among which the ompS mutant strain showed the most obvious decrease in virulence,LD50 was 25 times that of the standard strain.In conclusion,mutations of the pore protein ompW,ompS,and ompD genes can affect some biological properties of Salmonella typhimurium.The results of this study laid an experimental foundation for further research on the biological functions of the pore protein ompW,ompS and ompD genes and Salmonella pathogenicity.