RESUMO
CLINICAL RELEVANCE: The pathogenesis of chronic dacryocystitis (CDC) is associated with a variety of bacteria. Investigating microflora has the potential to provide a theoretical basis for preventing and treating CDC. BACKGROUND: 16S rRNA sequencing is a sequence-based bacterial analysis. The application of 16S rRNA sequencing in CDC is rarely reported. METHODS: A case-control study of infected and healthy eyes diagnosed as CDC patients was conducted. Seventy-eight patients were divided into A (conjunctival sac secretions from healthy eyes), B (conjunctival sac secretions from affected eyes), and C (lacrimal sac secretions from affected eyes) groups. The flora of samples was analysed with 16S rRNA sequencing, and the data was analysed using QIIME, R, LefSE and other software. The potential functions were analysed by PICRUSt. RESULTS: A total of 1440 operational taxonomic units (OTUs) were obtained, 139 specific to group A, 220 specific to group B, and 239 specific to group C. There was no significant difference in α index between the three groups. The beta diversity and grouping analysis data indicated that the three groups of flora were similar in species richness and diversity, but there were some differences in composition. In group A, the abundance of Pseudomonadaceae, Chlorobacteria, Moraceae, Staphylococcaceae, Bacillariophyceae, Immunobacterium spp. and Bacillus spp. was higher; in group B, the abundance of Burkholderiaceae, Sphingomonas, Rhizobia, Stalked Bacteria, Sphingomonadaceae, Enterobacteriaceae, Shortwaveomonas spp. was higher; in group C, the abundance of Streptococcus digestiveis, Propionibacterium, Enterobacteriaceae, Anaerobacteriaceae, Propionibacteriaceae, Bacillus spp. Neisseria spp. and Shortactomonas spp. was higher. Six pathways were identified to assess the potential microbial functions. CONCLUSION: Alterations in the microbiota of the conjunctiva and lacrimal sac are associated with the pathogenesis of CDC, which may provide certain guidance for antibiotic treatment of CDC.
RESUMO
BACKGROUND AND OBJECTIVE: Literature has reported that circular RNAs (circRNAs) are crucially associated with diabetic retinopathy (DR). Furthermore, circEHMT1 has been identified to maintain endothelial cell barrier function. This study aimed to investigate the mechanisms that regulate aberrant circEHMT1 expression and its role in the pathogenesis of DR. METHODS: In this study, retinal microvascular endothelial cells were exposed to a high glucose (HG) environment, and subsequently, tube formation and intercellular junction proteins were evaluated. Furthermore, the biological functions of circEHMT1 and its potential regulatory factor, eIF4A3, in microvascular endothelial cells under HG conditions were also assessed. In addition, the regulatory role of eIF4A3 on circEHMT1 expression was confirmed. Moreover, to elucidate the in vivo functions of eIF4A3 and circEHMT1, streptozotocin (STZ) was used to establish a DR model in rats. RESULTS: It was revealed that HG condition decreased circEHMT1 and eIF4A3 expressions and reduced ZO-1, Claudin-5, and Occludin levels in retinal microvascular endothelial cells. Furthermore, it was observed that eIF4A3 could regulate the expression of circEHMT1. Overexpression of eIF4A3 or circEHMT1 under HG conditions improved endothelial cell injury and decreased tube-formation ability. Additionally, in the DR rat model, eIF4A3 overexpression restored circEHMT1 levels and ameliorated retinal vasculature changes. CONCLUSION: Altogether, eIF4A3 regulates circEHMT1 expression, thereby affecting microvascular endothelial cell injury and tube formation. Further understanding the regulatory effect of eIF4A3 on circEHMT1 may provide novel therapeutic targets for DR.