Defective viral genomes (DVGs) are generated ubiquitously in many RNA viruses, including SARS-CoV-2. Their interference activity to full-length viruses and IFN stimulation provide the potential for them to be used in novel antiviral therapies and vaccine development.

BackgroundTo describe the prevalence and associations of posterior vitreous detachment (PVD) in a rural adult Chinese population.MethodsAll eligible subjects were requested to carry out a comprehensive eye examination; PVD was a pre-specified outcome variable and was determined via biomicroscopical examination (slit-lamp biomicroscopy) with a +90-D preset lens after mydriasis. Prevalence was standardized to China population census (2000).Results5890 (86.2%) subjects completed the examination of slit-lamp biomicroscopy with a +90-D lens. PVD was present in 160 participants (2.7%); the standardized prevalence was 2.0% (95% confidence interval [CI], 1.6-2.3%). PVD developed increasingly with age (P for trend < 0.001) for both men and women. Using a multivariate regression model, older people were found to run a higher risk of developing PVD than younger people, and women were found to have a higher risk than men (OR, 2.9; 95% CI, 1.5-5.9). Diabetes, hypertension, smoking, drinking, and intraocular pressure (IOP) were not significantly associated with PVD.ConclusionsAbout one in fifty people is found to have PVD in this population-based study. Age and female are independently associated with PVD occurrence.

The present study aimed to investigate the effects of histone deacetylase 6 (HDAC6) inhibitor Cay10603 (Cay) on high glucose (HG)-stimulated human retinal pigment epithelium (RPE) cells and its underlying mechanisms. ARPE-19 cells were cultured under normal glucose (NG) or high glucose (HG) conditions. The results revealed that HDAC6 was upregulated in HG-stimulated ARPE-19 cells. Cay treatment caused a decrease in intracellular reactive oxygen species (ROS). The levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were reduced accompanied by increase in the activities of superoxide dismutase (SOD) and catalase (CAT) after treatment with Cay. Besides, Cay decreased the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and monocyte chemoattractant protein-1 (MCP-1) in supernatant. Meanwhile, the apoptotic rate in Cay-treated ARPE-19 cells notably reduced, coupled with an upregulation in Bcl-2 expression and a downregulation in cleaved caspase-3 and cleaved caspase-9 expression. Cay decreased the expression of phospho (p)-NF-κB p65, p-IκB-α, NLRP3, cleaved caspase-1 and ASC while increased the expression of NF-κB p65 (cytoplasm). Taken together, these findings demonstrated that Cay suppressed HG-induced oxidative stress, inflammation and apoptosis via regulating NF-κB and NLRP3 inflammasome pathway in HG-induced ARPE-19 cells, suggesting that Cay might be a therapeutic agent for the treatment of diabetic retinopathy.

Defective viral genomes (DVGs) have been identified in many RNA viruses as a major factor influencing antiviral immune response and viral pathogenesis. However, the generation and function of DVGs in SARS-CoV-2 infection are less known. In this study, we elucidated DVG generation in SARS-CoV-2 and its relationship with host antiviral immune response. We observed DVGs ubiquitously from RNA-seq datasets of in vitro infections and autopsy lung tissues of COVID-19 patients. Four genomic hotspots were identified for DVG recombination and RNA secondary structures were suggested to mediate DVG formation. Functionally, bulk and single cell RNA-seq analysis indicated the IFN stimulation of SARS-CoV-2 DVGs. We further applied our criteria to the NGS dataset from a published cohort study and observed significantly higher DVG amount and frequency in symptomatic patients than that in asymptomatic patients. Finally, we observed unusually high DVG frequency in one immunosuppressive patient up to 140 days after admitted to hospital due to COVID-19, first-time suggesting an association between DVGs and persistent viral infections in SARS-CoV-2. Together, our findings strongly suggest a critical role of DVGs in modulating host IFN responses and symptom development, calling for further inquiry into the mechanisms of DVG generation and how DVGs modulate host responses and infection outcome during SARS-CoV-2 infection.