Background Receptor for advanced glycation end products (RAGE) play an important role in the process of type 2 diabetes and its microvascular complications.RAGE gene Gly82Ser exists polymorphism,but the correlation of gene polymorphism and diabetic retinopathy (DR) needs further research.Objective This study was to investigate the association of Gly82Ser polymorphism of RAGE gene with DR in Han people of Wuxi area with type 2 diabetic mellitus.Methods One hundred and eighty-five patiens with type 2 diabetes were included in Wuxi district from March 2013 to February 2014.The patients were divided into non DR (NDR) group (93 cases) and DR group (92 cases) according to the DR International Clinical Classification Criteria in 2002,and 120 healthy subjects were included at the same time as the control.All of the subjects received eye examinations,body mass index (BMI) and blood pressure measurement as well as laboratory tests,including blood biochemical indexes,blood lipids and fasting blood glucose levels.The peripheral blood of 3 ml was collected from each subject,and the genotype and allelic frequencies were assayed by PCR-direct sequencing.This study protocol was approved by Ethic Committee of Nanjing Medical University.Written informed consent was obtained from each subject prior to any medical examination.Results The course was significantly longer in the DR group than that in the NDR group (t =2.25,P =0.01).There were two alleles of G and A in the RAGE gene Gly82Ser locus in all the subjects and the distribution of single nucleotide polymorphism was in accordance with Hardy-Weinberg equilibrium (DR group:x2 =0.51,P =0.48;NDR group:x2 =1.38,P =0.24;healthy control group:x2 =0.20,P =0.24).The AA genotype frequency of the subjects in DR group,NDR group and healthy control group were respectively 6.5％,3.2％ and 2.5％,and AA genotype frequency in DR group was higher than that of the NDR group and healthy control group,showing significant intergroup differences (x2 =5.146,P =0.023;x2 =5.039,P =0.037).The distribution of A allele frequency in the DR group was significantly higher than that of NDR group and healthy control group (x2=5.494,P=0.019;x2 =5.235,P =0.023),and the frequencies of G allele and GG genotype in the DR group were lower than those of the NDR and the healthy control group (GG:x2 =4.260,P =0.039;x2 =4.794,P =0.027;G:x2 =5.309,P =0.021;x2 =5.476,P=0.032).No significant differences were seen in the frequencies of genotype and allele of subjects between the NDR group and the healthy control group (AA:x2 =5.346,P=0.127;GG:x2 =6.981,P=0.137;A:x2 =5.618,P =0.082;G:x2 =4.860,P =0.088).Conclusions The Gly82Ser polymorphism of RAGE gene is associated with the pathogenesis of DR in Han population with type 2 diabetes and A allele may be a risk factor of DR.

AIM: To investigate the efficacy of pars plana vitrectomy(PPV)with or without inner limiting membrane(ILM)peeling in refractory diabetic macular edema.METHODS:Totally 80 patients with refractory diabetic macular edema were retrospectively selected and assigned into groups according to the treatment method. Among them, 38 patients treated with PPV were included as group A, and 42 patients treated with PPV combined with ILM peeling were included as group B. The relevant data of patients in the two groups were collected, and the efficacy of the two groups was compared.RESULTS: At 1, 3, and 6 mo after surgery, the best corrected visual acuity(BCVA), central macular thickness(CMT), and severity of macular edema in the group B were all superior to those in the group A(all P<0.05). At 6 mo after the surgery, the incidence of complications in the group B was 12%, with no prominent difference compared to 18% of the group A(P>0.05).CONCLUSION:PPV combined with or without ILM peeling can improve visual function and relieve macular edema in patients with refractory diabetic macular edema. However, the combination of PPV and ILM peeling is superior to PPV alone in improving vision and relieving macular edema, and does not increase postoperative complications.

AIM: To predict diabetic retinopathy(DR)progression through macular layer thickness in diabetic patients detected by optical coherence tomography(OCT).METHODS: Retrospective study. The clinical data of 100 cases(200 eyes)of diabetic patients admitted to our hospital from January 2023 to September 2024 were collected. According to the international clinical DR classification, they were divided into the non-diabetic retinopathy(NDR)group with 32 cases(64 eyes), the non-proliferative diabetic retinopathy(NPDR)group with 38 cases(76 eyes), and the proliferative diabetic retinopathy(PDR)group with 30 cases(60 eyes). At the same time, 49 cases(98 eyes)of healthy controls whose age and gender were matched with those of the diabetic patients were collected as the normal group. All patients underwent OCT examination. The thickness changes of the retinal nerve fiber layer(RNFL), ganglion cell layer(GCL), inner plexiform layer(IPL), outer nuclear layer(ONL), photoreceptor cell layer and total retinal thickness(RT)in the subregions of the macular area were compared among the groups. The Eta coefficient was used to analyze the correlation between them and the severity of DR.RESULTS: The thickness of RNFL, GCL, IPL, ONL and photoreceptor cell layer in each sub-region and the average of macular area in the PDR group was significantly lower than that in the NDR and normal groups, while the average RT thickness was significantly higher than that in the NPDR, NDR and normal groups(all P<0.05). The thickness of RNFL(central area, upper inner and outer rings and lower inner and outer rings and average), GCL(upper inner and outer rings and lower inner and outer rings and average), IPL(upper inner ring), ONL(central, upper inner ring and lower inner ring)and photoreceptor cell layer(upper inner and outer rings and lower inner and outer rings and average)in macular area of the PDR group was significantly thicker than that in the NPDR group(all P<0.05). The thickness of RNFL, GCL, IPL, ONL and photoreceptor cell layer in each sub-region and the average of macular area in the NPDR group was significantly lower than that in the NDR and normal groups, while the average RT thickness was significantly thicker than that in the NDR and normal groups(all P<0.05). There was no statistically significant difference in the above indicators between the NDR group and the normal group(all P>0.05). The severity of DR was significantly correlated with the average thickness of RNFL, GCL, IPL, ONL, photoreceptor cell layer and RT in macular area(all P<0.001).CONCLUSION: OCT measurement of the thickness of RNFL, GCL, IPL, ONL, photoreceptor cell layer and RT in the macular area in the diabetic patients can evaluate the progression of DR.