The vitreous substitute for proliferative vitreoretinopathy (PVR) surgery remains an unmet clinical need in ophthalmology. In our study, we developed an in situ formed hydrogel by crosslinking polyvinyl alcohol (PVA) and chitosan as a potential vitreous substitute. 5-fluorouracil (5-FU) Poly (lactic-co-glycolic acid) (PLGA) microspheres were developed and loaded onto the PVA/chitosan hydrogels to treat PVR. In vitro, PVA/chitosan hydrogels at four concentrations were subjected to morphological, physical, rheological analyses, and cytotoxicity was evaluated together with the characterization of 5-FU PLGA microspheres. In vivo, pharmacologically induce PVR rabbits were performed a vitrectomy. In the PVA group, 3% PVA/chitosan hydrogel was injected into the vitreous cavity. In the PVA/MS group, 3% PVA/chitosan hydrogel and 5-FU PLGA microspheres were injected. In the Control group, phosphate-buffered saline was injected. Therapeutic efficacy was evaluated with postoperative examinations and histological analyses. This study demonstrated that the 3% PVA/chitosan hydrogel showed properties similar to those of the human vitreous and could be a novel in situ crosslinked vitreous substitute for PVR. Loading 5-FU PLGA microspheres onto this hydrogel may represent an effective strategy to improve the prognosis of PVR.

The aim of this study was to investigate the role of pre-B cell colony-enhancing factor (PBEF) in the pathogenesis of bronchopulmonary dysplasia (BPD) using an established cell model of BPD. For this purpose, EA.hy926 cell cultures were divided into 4 groups as follows: the air group as the blank control, the hyperoxia group, the hyperoxia plus PBEF siRNA group and the hyperoxia plus scramble siRNA group. Cell viability and the generation of reactive oxygen species (ROS) were determined using respective kits. Moreover, the protein and mRNA expression levels of PBEF, interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α) were also detected by corresponding methods. Compared with the hyperoxia group, the ROS levels in the hyperoxia plus PBEF siRNA group were significantly reduced (P<0.01). The silencing of PBEF increased cell viability compared with the hyperoxia group. The protein and mRNA expression levels of PBEF, IL-8 and TNF-α were all decreased in the hyperoxia plus PBEF siRNA group compared with the hyperoxia group (P<0.01). Our study thus demonstrates that the inhibition of PBEF attenuates oxidative stress and inflammation induced by hyperoxia in EA.hy926 cells, suggesting that PBEF may be a potential diagnostic and therapeutic target, which may be used for the development of novel treatment strategies for BPD.