In silico and in vitro evaluation of antiviral activity of wogonin against main protease of porcine epidemic diarrhea virus.

The high mortality rate of weaned piglets infected with porcine epidemic diarrhea virus (PEDV) poses a serious threat to the pig industry worldwide, demanding urgent research efforts related to developing effective antiviral drugs to prevent and treat PEDV infection. Small molecules can possibly prevent the spread of infection by targeting specific vital components of the pathogen's genome. Main protease (Mpro, also named 3CL protease) plays essential roles in PEDV replication and has emerged as a promising target for the inhibition of PEDV. In this study, wogonin exhibited antiviral activity against a PEDV variant isolate, interacting with the PEDV particles and inhibiting the internalization, replication and release of PEDV. The molecular docking model indicated that wogonin was firmly embedded in the groove of the active pocket of Mpro. Furthermore, the interaction between wogonin and Mpro was validated in silico via microscale thermophoresis and surface plasmon resonance analyses. In addition, the results of a fluorescence resonance energy transfer (FRET) assay indicated that wogonin exerted an inhibitory effect on Mpro. These findings provide useful insights into the antiviral activities of wogonin, which could support future research into anti-PEDV drugs.`.

Evaluation and Follow-up of Myopia Prevalence Among School-Aged Children Subsequent to the COVID-19 Home Confinement in Feicheng, China.

Importance: Progression of myopia in a school-aged population due to home confinement (January to May 2021) during the COVID-19 pandemic has been previously reported. A key remaining question was whether the myopia spike in children aged 6 to 8 years persisted. Objective: To investigate the changes in refractive status and prevalence of myopia in school-aged children 1 year after home confinement ended in China. Design, Setting, and Participants: This cross-sectional study with a cohort substudy prospectively evaluated data from school-based photoscreening in Feicheng, China. Children aged 6 to 13 years participated in 8 screenings from 2015 to 2021. Exposures: Noncycloplegic photorefraction was conducted using the Spot Vision photoscreener. Main Outcomes and Measures: The main outcomes were the differences in spherical equivalent refraction (SER) and prevalence of myopia between 2020 (during home confinement) and 2021 (after home confinement). The SER was recorded for each child, and the prevalence of myopia was calculated annually for each age group. Results: A total of 325 443 children participated in the study (51.4% boys, 48.6% girls; age range, 6 to 13 years). Compared with 2020, the mean SER of children in 2021 increased significantly for those aged 6 (0.42 diopters [D]), 7 (0.41 D), and 8 (0.33 D) years. The prevalence of myopia in 2021 was similar to in 2019 for each age group (aged 6 years: 7.9% vs 5.7%; aged 7 years: 13.9% vs 13.6%; aged 8 years: 29.5% vs 26.2%). Both the prevalence of myopia and mean SER for these children returned to their prepandemic levels. Conclusions and Relevance: Compared with 2020, the prevalence of myopia among children aged 6 to 8 years in the 2021 screenings decreased, and the mean SER returned to prepandemic level. The refractive development in children aged 6 to 8 years may be most susceptible to environmental changes. These findings support the premise that age 6 to 8 years is a critical period for myopia development and suggest a need to focus preventive interventions for myopia control on children in this age range.

Progression of Myopia in School-Aged Children After COVID-19 Home Confinement.

Importance: Time spent in outdoor activities has decreased owing to home confinement for the coronavirus disease 2019 (COVID-19) pandemic. Concerns have been raised about whether home confinement may have worsened the burden of myopia owing to substantially decreased time spent outdoors and increased screen time at home. Objective: To investigate the refractive changes and prevalence of myopia in school-aged children during the COVID-19 home confinement. Design, Setting, and Participants: A prospective cross-sectional study using school-based photoscreenings in 123 535 children aged 6 to 13 years from 10 elementary schools in Feicheng, China, was conducted. The study was performed during 6 consecutive years (2015-2020). Data were analyzed in July 2020. Exposures: Noncycloplegic photorefraction was examined using a photoscreener device. Main Outcomes and Measures: The spherical equivalent refraction was recorded for each child and the prevalence of myopia for each age group during each year was calculated. The mean spherical equivalent refraction and prevalence of myopia were compared between 2020 (after home confinement) and the previous 5 years for each age group. Results: Of the 123 535 children included in the study, 64 335 (52.1%) were boys. A total of 194 904 test results (389 808 eyes) were included in the analysis. A substantial myopic shift (approximately -0.3 diopters [D]) was found in the 2020 school-based photoscreenings compared with previous years (2015-2019) for younger children aged 6 (-0.32 D), 7 (-0.28 D), and 8 (-0.29 D) years. The prevalence of myopia in the 2020 photoscreenings was higher than the highest prevalence of myopia within 2015-2019 for children aged 6 (21.5% vs 5.7%), 7 (26.2% vs 16.2%), and 8 (37.2% vs 27.7%) years. The differences in spherical equivalent refraction and the prevalence of myopia between 2020 and previous years were minimal in children aged 9 to 13 years. Conclusions and Relevance: Home confinement during the COVID-19 pandemic appeared to be associated with a significant myopic shift for children aged 6 to 8 years according to 2020 school-based photoscreenings. However, numerous limitations warrant caution in the interpretation of these associations, including use of noncycloplegic refractions and lack of orthokeratology history or ocular biometry data. Younger children's refractive status may be more sensitive to environmental changes than older ages, given the younger children are in a critical period for the development of myopia.