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Objective@#To investigate the status and trend of low vision of junior and senior high school students in Beijing from 2009 to 2018, and to provide evidence for myopia prevention.@*Methods@#Data came from the results of physical examination of eyesight in 2009-2018 in Beijing, which were cdlected among juncor and senior high school students in March every year. Detection rate of low vision of students and the difference across different districts and counties were analyzed.@*Results@#From 2009 to 2018, the rate of low vision of high school and college entrance examination students in Beijing was on the rise, with the average rate of low vision of 86.07% and 76.36% respectively. Similar trend was found in the rate of high myopia(16.39% and 18.64%,respectively), while that of light and medium myopia tends to be stable. The highest rate of low vision among junior middle school students was in Xicheng (84.75%) District and Chaoyang District (84.03%), and for high middle school students,the highest rate of myopia was found in Fengtai District (91.17%) and Dongcheng District (89.92%).@*Conclusion@#In Beijing, the detection rate of low vision of middle school and college entrance examination students increased steadily, especially the high myopia. The health education of eyesight protection is of great significance to students. It is necessary to strengthen the extensive intervention of eyesight protection in middle and college entrance examination students.
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Objective To examine role and possible mechanism of enriched environment (EE) on regulating recovery of visual function in adult monocular deprivation amblyopia mice.Methods A total of 72 healthyKunming mice were divided into normal control group,monocular deprivation (MD) group,MD+EE group and M D+ fluoxetine group by random number table.Except for the normal control group,the mice in the other groups were sutured on the right eyelid 21 days after birth to establish MD amblyopia model.the mice were fed in standard environment or EE for 4 weeks according to the group.Visual acuity and flash visual evoked potential (F-VEP) of mice in each group were detected.The distribution of microtubule associated protein 2 (MAP2) in visual cortex of adult amblyopic mice were detected by immunohistochemistry.The expression of MAP2,synaptophysin (SYP) and postsynaptic density protein-95 (PSD-95) protein in visual cortex of adult amblyopic mice were detected by western blot.The experimental protocol was approved by the Animal Care and Use Committee of Hunan Children's Hospital and conformed to the National Institutes of Health Guide for the Care and Use of Laboratory Animals.Results There was a significant difference in the visual acuity of deprived eye among each group (F=114.632,P＜0.001).The visual acuity in MD group is lower than that in normal control group,with a significant difference (t =15.480,P＜0.001).Compared with MD group,visual acuity was restored in MD+ EE group and MD +fluoxetine group,with significant differences (t =15.071,P ＜ 0.001;t =14.841,P ＜ 0.001).There was a significant difference in the P2 latency and amplitude of F-VEP in deprived eye among each group (F=36.510,P=0.000;F=34.140,P=0.000).Compare with normal control group,P2 latency was prolonged and P2 amplitude of F-VEP was decreased in deprived eye in MD group,with significant differences (t =10.220,P =0.000;t =10.09,P =0.000).Western blot assay showed that there was a significant difference in the expression of MAP2 in visual cortex contralateral deprived eye among each group (F=18.142,P=0.000).The expression of MAP2 in MD group was significantly lower than that in normal contral group (t=3.056,P＜0.01);Compared with MD group,MAP2 expression was increased in MD+EE group and MD+fluoxetine group (t =2.541,P =0.031;t =2.157,P =0.017).There were significant differences in the expression of SYP and PSD-95 in visual cortex contralateral to deprived eye among each group (F =12.871,P =0.000;F =25.060,P =0.000).Compared with normal contral group,SYP and PSD-95 expression in visual cortex were down-regulated in MD group,with significant differences (t =6.054,P =0.000;t =8.631,P =0.000).The expression of SYP and PSD-95 protein in MD+EE group and MD+fluoxetine group were significantly higher than those in MD group (all at P＜0.05).Conclusions EE can recover visual function through up-regulating the expression of MAP2,which can modulate the dendritic branch trim and neural plasticity of visual cortex in adult MD mice.
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Objective To investigate pathological changes of lens epithelium cells (LECs) and expressions of matrix metalloproteinase-3 (MMP-3),alpha-smooth muscle actin (α-SMA),and fibronectin (Fn) in lens epithelial cells of experimental diabetic cataract rats,and to evaluate the roles of MMP-3,α-SMA,and Fn in the pathogenesis of diabetic cataract.Methods A total of 105 healthy Sprague-Dawley (SD) rats without lens diseases was randomly divided into normal control (n =45) and diabetic model (n =60) groups.Diabetic model rats were subjected to intraperitoneal injection of streptozotocin (STZ) (60 mg/kg),and those in the normal control group received injection with 0.1 mmol/L citric acid buffer solution of the same volume.The diabetic models were affirmed upon a fasting blood ≥ 16.65 mmol/L at the 3rd days after the injection.Once a week,the changes of blood glucose and body weight were monitored and the progression of cataract formation in both lenses of all rats was recorded with slit lamp observation.At end of 4 weeks,8 weeks,and 12 weeks after STZ injection,lenses were isolated and embedded in paraffin.The LECs histopathology was examined with HE staining.Immunohistochemical method was used to detect expressions of MMP-3,α-SMA,and Fn in normal and diabetic LECs.The related comparisons and statistic analysis were carried out.Results The lenses of control group were always completely transparent throughout the period of experiment with 31.48％,77.78％,and 100％ of lenses in diabetic model group swelling at 4th,8th,and 12th week,respectively.Under the light microscopic level,it has been showed that lens epithelium cells,which was occurred aggregate plaque and arranged in many layers,presented some morphologic characteristics of fibroblasts by HE staining.In control group LECs regularly,MMP-3,α-SMA,and Fn did not express equally;MMP-3,α-SMA,and Fn expressions increased obviously highly,difference had statistical significance compared to diabetic cataract group LECs (P ＜ 0.01).With the development of course of disease,the differences in expression of MMP-3,α-SMA,and Fn were significant between the diabetic cataract LECs and the control group (P ＜ 0.01).During the progression of diabetic cataract,the expression of Fn was positively correlated with that of α-SMA and MMP-3 (r =0.994,P ＜ 0.01;r =0.993,P ＜ 0.01).Conclusions The diabetic cataract liyingbody animal model was established successfully,which has laid down necessary basis to expound the morbidity mechanism of diabetic cataract.In the lens of diabetic cataract group,the expressions of α-SMA,MMP-3,and Fn were significantly increased.They participated in the occurrence and development of diabetic cataract.The expression of Fn was positively correlated with α-SMA and MMP-3.The lens epithelium cells which took on elongated aspect like fibroblast cells appeared epithelial-mesenchymal transformation (EMT),which mediated the occurrence and development of LECs fibrosis.