ABSTRACT
Objective@#To explore the association between reading and writing posture with the occurrence of myopia in Chinese children and adolescents, so as to provide a reference for reducing its prevalence among primary and secondary school students.@*Methods@#Using data from the 2020 survey on the current status of hyperopia reserve in primary and secondary school students from six provinces/cities, namely Beijing, Zhejiang, Chongqing, Shaanxi, Liaoning, and Henan selected by multi stage stratified cluster probability sampling method during November 2020 to June 2022. A total 16 782 students who completed the optometry examination of cycloplegia according to the Children and Adolescents Myopia Screening Standard and questionnaire survey were included for analyzing analyze the association between reading and writing posture with myopia.@*Results@#The overall detection rate of myopia among primary and secondary school students was 45.7%, of which 35.0% were primary school students, 84.1% junior high school students, and 90.4% senior high school students. Poor reading and writing posture was found in 73.6% of primary and secondary school students. Adjusting for confounding factors such as gender, school period, region, outdoor time every day, and whether parents were myopic, the results of the multilevel Logistic regression showed that the following factors were positively correlated with myopia:poor reading and writing posture ( OR=1.17, 95%CI =1.07-1.28), never/occasionally reading and writing with a reading distance which was more than one foot away between the eyes and book ( OR=1.28, 95%CI=1.08-1.53, OR=1.23, 95%CI = 1.08- 1.40), teachers occasionally reminding the child of their reading and writing posture ( OR=1.13, 95%CI =1.01-1.25), and often/always reading and writing while lying down or with the face on the arm ( OR=1.15, 95%CI=1.01-1.32, OR=1.46, 95% CI = 1.17-1.82), always reading and writing with the head in the hand ( OR=1.56, 95%CI =1.20-2.01). Further, a negative correlation was detected between myopia and parents occasionally reminding their children of their reading and writing posture ( OR= 0.85 , 95%CI =0.76-0.96) ( P <0.05).@*Conclusion@#Poor reading and writing posture is a risk factor for the development of myopia in primary and secondary school students, and interventions for reading and writing posture need to be strengthened to reduce the occurrence of myopia among primary and secondary school students.
ABSTRACT
High-affinity α-glucosidase inhibitors were screened from Cichorium glundulosum Boiss.et Hout seed (CGS) extract by ultra-filtration affinity-liquid chromatography-mass spectrometry (UF-LC-MS) and molecular docking.By taking 4-nitrobenzene-α-D-glucopyranoside (PNPG) as substrate and acarbose as positive control to evaluate the inhibitory activity of CGS extract, IC50 of acarbose and CGS extract were 0.003 mg/mL and 0.447 mg/mL, respectively.Meanwhile, 4 compounds from CGS extract by UF-LC-MS were screened and identified.Then by using autodock software, the compounds that combined with α-glucosidase were well screened out, including chlorogenic acid and isochlorogenic acid A.The inhibitory activity of chlorogenic acid and chlorogenic acid A against α-glucosidase was verified in vitro.The results showed that the inhibitory activity of the compounds toward α-glucosidase presented the sequence of acarbose>isochlorogenic acid A>chlorogenic acid.The inhibition rate of isochlorogenic acid A was close to acarbose.The experimental results illustrated that UF-LC-MS and molecular docking could be used to screen high affinity enzyme inhibitors from CGS.