ABSTRACT
AIM: To assess the prevalence, causes, and risk factors for blindness and visual impairment among elderly (≥60 years of age) Chinese people in a metropolitan area of Shanghai, China. METHODS: Random cluster sampling was conducted to identify participants among residents ≥60 years of age living in the Xietu Block, Xuhui District, Shanghai, China. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) were checked by the Early Treatment Diabetic Retinopathy Study (ETDRS) visual chart. All eligible participants underwent a comprehensive eye examination. Blindness and visual impairment were defined according to World Health Organization (WHO) criteria. RESULTS: A total of 4190 persons (1688 men and 2502 women) participated in the study, and the response rate was 91.1%. Based on PVA, the prevalence of blindness was 1.1% and that of visual impairment was 7.6%. Based on BCVA, the prevalence of blindness and visual impairment decreased to 0.9% and 3.9%, respectively. Older (≥80 years of age) women, with low educational levels and smoking habits, exhibited a significantly greater chance for blindness and visual impairment than did those with high educational levels and no smoking habits (P<0.05). Based on PVA and BCVA, the main causes of blindness were cataract, myopic maculopathy, and age-related macular degeneration (AMD). CONCLUSION: Our findings help to identify the population in need of intervention, to highlight the need for additional eye healthcare services in urban China.
ABSTRACT
PURPOSE: To determine the role of matrix metalloproteinase 9 (MMP9) in advanced glycation end-products (AGEs) induced damage to blood-retinal barrier (BRB) and the therapeutic effects of minocycline, an MMP inhibitor, against the BRB damages. METHODS: Forty-eight Sprague Dawley rats were randomly assigned to 3 groups (16/group): A control group treated with bovine serum albumin (BSA), an AGE-BSA treated group, and a group treated with minocycline after AGE-BSA treatment. The retinas of all the animals were collected 2 weeks after treatment, and the levels of MMP9 protein and mRNA were detected by Western blotting, immunohistochemistry, and semi-quantitative RT-PCR. The permeability of retinal vessels was bio-assayed using the Evans Blue method. The correlation between the vessel permeability and the MMP9 protein levels was analyzed. RESULTS: Compared with the BSA control group, the expression of retinal MMP9 mRNA and protein were significantly increased in the AGE-BSA group, and the retinal vascular permeability was also increased in the AGE-BSA group. After the minocycline treatment, the MMP9 expression was decreased sharply and the abnormal vascular permeability was improved. There was a significant correlation between the MMP9 expression and retinal vascular permeability. CONCLUSION: MMP9 is involved in the AGE-induced retinal damage of vascular permeability, and the abnormal permeability can be partially reversed by treatment with minocycline.
