Purpose The study aimed to investigate the prevalence of dry eye disease (DED) and relevant risk factors among Chinese high school students during the COVID-19 outbreak. Methods A cross-sectional study was conducted from November to December 2020, and 4825 high school students from nine high schools in Shanghai were recruited. All students completed ocular surface disease index (OSDI) and perceived stress scale (PSS) questionnaires and answered other questions designed to ascertain information on the risk factors related to DED. DED was diagnosed when OSDI scores were greater than or equal to 13. The prevalence of symptomatic DED was determined. A T-test, Kruskal-Wallis test, Chi-square test, and logistic regression analysis were used to examine the possible risk factors. Results The prevalence of symptomatic DED among Chinese high school students was 70.5%. In univariate analysis, higher PSS scores (P<0.001), prolonged video display terminal (VDT) use (P<0.001), wearing contact lenses (P=0.001), poor sleep quality (P<0.001), and being female (P<0.001) were significantly correlated with dry eyes. In multivariate logistic regression analysis, higher PSS scores (P<0.001, OR=1.20), prolonged VDT use (P<0.001, OR=1.07), poor sleep quality (P<0.001, OR=1.84), and being female (P=0.001, OR=1.25) were significant risk factors associated with DED. Conclusions Due to the epidemic, most Chinese high school students are in a high-risk environment in which they are more likely to suffer from DED, such as long online courses and heavy stress from school. Relevant preventive measures that may have a positive impact on public health and quality of life for high school students should be brought to the forefront.

The present study has reported a novel method for producing induced pluripotent stem (iPS) cells. Primary human amniotic epithelial cells (HuAECs) were isolated from the amniotic membranes of pregnant women who received Cesarean sections. These cells were infected with retroviruses carrying octamer-binding transcription factor 4 (Oct4), (sex determining region Y)-box 2 (Sox2) and Yes-associated protein (Yap) (OSY). Following in vitro culture for ~14 days, epithelial-like HuAECs exhibited several iPS clone-like cell colonies (OSY-iPS). These cell clones presented positive alkaline phosphatase features and expressed high levels of embryonic stem cell-like markers (Nanog homeobox, Sox2, Oct4, reduced expression protein 1, and SSES3/4). Additionally, epigenetic analysis results indicated that the methylation of CpG islands on endogenous Oct4 and Sox2 promoters was reduced in OSY-iPS cells. Furthermore, the majority of the histone H3 at lysine 9 sites that interacted with the Oct4 and Sox2 promoters were acetylated, suggesting that the transcription activities of the above two transcription factors significantly increased. In vivo and in vitro induced differentiation experiments demonstrated that OSY-iPS could develop into embryoid bodies in vitro, and express numerous cellular markers in the three germ layers. Furthermore, OSY-iPS could form teratomas in immunodeficient mice. The pathological detection results suggest that these teratomas contain numerous types of cells from the three germ layers. However, the results from the quantitative polymerase chain reaction and western blot analyses suggest that the Hippo-Yap signaling pathway was significantly activated in OSY-iPS cells. In conclusion, a novel method for iPS induction was established in the present study. HuAECs were successfully induced to reprogram iPS cells through the introduction of OSY to activate the Hippo-Yap signaling pathway.

Cryoinjury, or injury caused by extremely low temperatures, can occur in corneal endothelial cells (CECs) and lead to visual impairment. However, the mechanism of cryoinjury in CECs is not clear. The Stk11-p53 signaling pathway regulates the proliferation and division of cells. Activity of the Stk11-p53 signaling pathway arrests the cell cycle at the G0/G1 phase and induces apoptosis. In this study, a mouse model of cryoinjury in CECs was used. Following injury, significant mouse CEC death and shedding were observed. In addition, the mRNA and protein levels of core factors from the Stk11-p53 signaling pathway (Stk11, p21 and p53) were elevated and Caspase-3 was activated following cryoinjury. In addition, chromatin immunoprecipitation revealed that Stk11 catalyzed p53 serine 15 phosphorylation, and the Stk11-p53 complex bound to the p21 promoter and stimulated gene transcription. Thus, the results of the present study suggest that cryoinjury leads to the damage and apoptosis of mouse CECs by activation of the Stk11-p53 signaling pathway, phosphorylation of p53 serine 15 and p21 gene transcription.

In the current study, the CLVQOL was used to assess VRQOL before unilateral or bilateral cataract surgery and at the end of the follow-up period in order to determine the greater beneficial mode of surgery for patients, if one of the two surgical methods is more beneficial over the other. The patients were classified as receiving unilateral (group A) and bilateral cataract surgery (group B). There were no significant differences between groups A and B before the operation in terms of life quality scores, binocular weighted average LogMAR BCVA, age, educational level, gender, systematic and ocular comorbidities, and the complications of the operation. It was shown that visual acuity improved more significantly with bilateral cataract surgery than with unilateral surgery in elderly patients with a high preoperative disease burden in Shanghai city. However, the improvement in life quality was not different in patients receiving either bilateral or unilateral cataract surgery.

Severe corneal injury is one of the main causes of loss of visual function. Mesenchymal stem cells (MSCs) have the ability to repair damaged cells in vivo. The present study aimed to explore whether MSCs could function as a cell therapy tool to replace traditional methods to treat corneal injury. CD44 + /CD105 + mesenchymal stem cells isolated from mouse amniotic fluid (mAF-MSCs) were injected into mice after cryoinjury to induce corneal endothelial cell injury. Histopathological assays indicated that mAF-MSCs could promote the growth of corneal epithelial cells, reduce keratitis, and repair the corneal damage caused by low temperature. cDNA microarray analysis revealed that the mAF-MSCs affected the expression patterns of mRNAs related to cell proliferation and differentiation pathways in the mice after transplantation. The results of quantitative real-time PCR and western blotting revealed that NAT12, NAT10, and the ETV4/JUN/CCND2 signaling axis were elevated significantly in the mAF-MSC-transplantation group, compared with those in the phosphate-buffered saline-treated groups. High performance liquid chromatography–mass spectroscopy results revealed that mAF-MSCs could promote mRNA N4-acetylcytidine (ac4C) modification and high expression of N-acetyltransferase in the eyeballs. RNA immunoprecipitation-PCR results showed that a specific product comprising Vegfa, Klf4, Ccnd2, Jun, and Etv4 mRNA specific coding region sites could be amplified using PCR from complexes formed in mAF-MSC-transplanted samples cross-linked with anti-ac4C antibodies. Thus, mouse amniotic fluid MSCs could repair the mouse corneal cold injury by promoting the ETV4/JUN/CCND2 signal axis activation and improving its stability by stimulating N4-acetylcytidine modification of their mRNAs.