Objective To observe the thickness changes in the peripapillary retinal nerve fiber layer(RNFL)and the ganglion cell-inner plexiform layer(GC-IPL)in the macular region,so as to analyze the pathological rules of retinal nerve injury in diabetes retinopathy(DR)patients and explore the related risk factors.Methods A total of 164 patients(164 eyes)with type 2 diabetes who visited the Department of Ophthalmology and Department of Endocrinology of Shaanxi Pro-vincial People's Hospital from January 1,2017 to January 1,2018 were selected as the subjects.According to the condition of concomitant DR,these subjects were divided into three groups:non-DR(NDR)group(56 eyes of 56 patients),mild non-proliferative DR(NPDR)group(53 eyes of 53 patients)and moderate NPDR group(55 eyes of 55 patients).Healthy individuals who underwent physical examinations in the same period were selected as the control group(50 eyes of 50 pa-tients).Optical coherence tomography and optical coherence tomography angiography were used to measure the peripapil-lary RNFL,macular GC-IPL,and macular vessel density(VD)of all subjects.Comparison among groups and correlation analysis were conducted on the above retinal nerve injury indicators.Results Compared with the control group and NDR group,the average,upper and lower peripapillary RNFL in the mild NPDR group and moderate NPDR group were signifi-cantly thinner,and the differences were statistically significant(all P＜0.05).The differences in macular GC-IPL thickness at the average,upper,upper temporal,lower temporal,lower,lower nasal,and upper nasal regions in all groups were sta-tistically significant(all P＜0.05);pairwise comparisons showed that compared with the control group,the GC-IPL thick-ness in each quadrant of the macular area of patients in the NDR group,mild NPDR group and moderate NPDR group de-creased significantly(all P＜0.05),with the upper GC-IPL thinning being the most significant;compared with the NDR group,the GC-IPL thickness in the upper,average,and upper temporal macular area of patients with mild NPDR decreased significantly(all P＜0.05);compared with the mild NPDR group,the GC-IPL thickness in the upper macular area was thin-ner in the moderate NPDR group,and the difference was statistically significant(P＜0.05).There were statistically signifi-cant differences in the average and inner ring VDs in the macular area among the groups(both P＜0.05).The correlation analysis results showed that there was a significantly positive correlation between the peripapillary RNFL thickness and the average VD in the macular area(r=0.517,P＜0.01),while the average GC-IPL thickness in the macular area was weakly positively correlated with the average VD in the macular area(r=0.279,P＜0.01).Conclusion The peripapillary RNFL thickness objectively reflects the degree of retinal neuron injury,and is a key index to evaluate the degree of retinal nerve injury in diabetes patients.

Objective To investigate the effects of microRNA-26a-5p(miR-26a-5p)on high glucose-induced retina Müller activation and apoptosis by regulating PTEN/PI3K/Akt signaling pathway,and the potential mechanism of diabetic retinal neurodegeneration.Methods Various concentrations of high glucose were added into rMC-1 culture.CCK-8 and flow cytometry was used to examine cell proliferation and apoptosis respectively.The regulatory effects of miR-26a-5p on the expressions of PTEN,PI3K and Akt were observed by real-time PCR;the expression levels of IL-1β and IL-6 in Müller cells were examined by ELISA.The data were processed by Graphpad 8.0 software.Results Müller cells grew actively in high-glucose stimulation culture.Compared with the control group,the activity of Müller cells stimulated by 50 mmol/L glucose increased gradually at 12 h and 24 h,but decreased at 48 h after stimulation,when Müller cells apoptosis increased.The difference between the groups was statistically significant(P＜0.05).The expression of miRNA-26a-5p decreased,that of PTEN increased,and those of PI3K and Akt decreased.Meanwhile,IL-1β and IL-6 levels were significantly increased in Müller cells.miR-26a-5p over-expression alleviated injuries to high glucose stimulated retinal Müller cells by inhibiting PTEN,which upregulated the expression of PI3K/Akt and downregulation of IL-1β and IL-6(P＜0.01).Conclusion Upregulating miR-26a-5p protects Müller cells against apoptosis,probably through regulation of PTEN/PI3K/Akt and affecting the production of inflammatory factors.

[Objective] To analyze the characteristics of HLA-A, HLA-B, HLA-DRB1, HLA-C, HLA-DQB1 and HLA-DPB1 allele polymorphisms among cord blood donors in Guangdong population. [Methods] According to HLA high resolution genotyping data of 32 717 samples of cord blood donors from Guangdong Cord Blood Bank from January 2009 to December 2023, the allele frequencies were calculated by direct counting and the haplotype frequencies were calculated by using Arlequin software 3.5.2.2. [Results] A total of 102 HLA-A alleles, 160 HLA-B alleles and 96 HLA-DRB1 alleles were detected in 32 717 samples. Among them, 46 HLA-DPB1 alleles were detected in 5 377 samples, and 66 HLA-C alleles and 35 HLA-DQB1 alleles were detected in 13 310 samples. The most common alleles were HLA-A^*11∶01 (28.96%), HLA-B^*40∶01 (15.23%), HLA-DRB1^*09∶01 (15.72%), HLA-C^*01∶02 (19.40%), HLA-DQB1^*03∶01 (20.85%) and HLA-DPB1^*05∶01 (40.79%). The most common 3 loci haplotype and 6 loci haplotype were HLA-A^*02∶07-B^*46∶01-DRB1^*09∶01 (1.55%), HLA-C^*07∶02-DQB1^*03∶01-DPB1^*05∶01 (1.77%), HLA-DRB1^*09∶01-DQB1^*03∶03-DPB1^*05∶01 (3.31%) and HLA-A^*02∶07-B^*46∶01-C^*01∶02-DRB1^*09∶01-DQB1^*03∶03-DPB1^*05∶01 (0.30%). [Conclusion] In this study, the allele and haplotype frequencies of HLA-A, HLA-B, HLA-DRB1, HLA-C, HLA-DQB1 and HLA-DPB1 were obtained in the cord blood donors in Guangdong, which can provide important reference data for HLA gene related research and the selection of donors for clinical application.

AIM: To study the protective effect of fenofibrate on diabetic retinal neurodegeneration and observe its effect on miR-26a-5p and its target gene PTEN in the retinal of diabetic mice.METHODS: Diabetic mice models were established and they were gavaged by fenofibrate. H& E staining and transmission electron microscopy were used to observe the impairments of retinal neurons. Real-time PCR was used to examine the expression of miR-26a-5p, and Western blotting was employed to measure the expression of phosphatase and tensin homologue(PTEN)in the retina of diabetic mice. The expression level of nuclear factor-κB(NF-κB), interleukin-1β(IL-1β)and the morphology of neural tissues were observed.RESULTS: When compared with the diabetic mice, fenofibrate significantly attenuated the damage to retinal ganglion cells and the atrophy of retinal nerve fiber layer. While the level of miR-26a-5p was increased and the levels of PTEN and inflammatory mediators were significantly decreased in the retina of fenofibrate treated diabetic mice, with significant statistical significance(P<0.05).CONCLUSIONS: Fenofibrate protects against diabetic retinal neurodegeneration by upregulating miR-26a-5p and inhibiting PTEN, attenuating the inflammatory response and alleviating retinal cell injury.