Objective: To study the correlation between electronic screen use and myopia among primary and secondary school students in six provinces and cities in China, in order to provide a scientific basis for comprehensive prevention and control of myopia. Methods: From November 2020 to June 2022, a total of 16 557 primary and secondary school students from six provinces and cities in China (Beijing City, Liaoning Province, Zhejiang Province, Henan Province, Shaanxi Province, Chongqing City) were selected by stratified cluster random sampling and probability smampling methods, and a questionnaire prepared by Beijing Center for Disease Control and Prevention was used to investigate their electronic screen use. According to Screening Criteria for Myopia in Children and Adolescents, 0.5% mass concentration of compound topicamide eye drops was used to paralyze the ciliary muscle and undergo slit lamp optometry. Chisquare test was used to compare the differences between groups, and binary Logistic regression was used to analyze the association between electronic screen use and myopia. Results: About 58.3% of primary and secondary school students used electronic screens for more than two hours a day on average, and 63.4% of primary and secondary school students used continuously electronic products for more than 15 minutes at a time for nonstudy purposes. After adjusting for confounding factors, parents unrestricted use of electronic screen time and electronic screen time ≥2 h/d were positively correlated with myopia (OR=1.27, 1.13, P<0.05). Gender stratified analysis showed that boys who used electronic screen time ≥2 h/d had a higher risk of myopia (OR=1.15, P<0.05). The results of grade stratification analysis showed that parents unrestricted electronic screen use time and electronic screen time ≥2 h/d were positively correlated with myopia in the lower grade of primary school students (OR=1.34, 1.18, P<0.05). Among the higher grade of primary school students, continuous use of electronic screens for nonstudy purposes for more than 15 minutes at one time was positively correlated with myopia (OR=1.18, P<0.05). There was a multiplicative interaction between total screen time and one continuous screen time (OR=1.04, P<0.05). Conclusions Primary and secondary students in six provinces and cities in China reports excessive electronic screen usage which is associated with myopia. Schools and parents should jointly limit the use of electronic screen among primary and secondary students to reduce the occurrence of myopia.

Objective: To assess the nutritional status of primary and secondary school students in Beijing City and to analyze the related factors, so as to provide a scientific basis for improving the nutritional status of primary and secondary school students in a targeted manner. Methods: Based on the 2021 Beijing Student Common Diseases and Health Influencing Factors Surveillance Project, a stratified random cluster sampling method was used to conduct a physical examination and questionnaire survey on 25 487 primary and secondary school students from September to November 2021. The Chi square test was used for comparison of nutritional status detection rates, and disordered multi classification Logistic regression analysis was used to explore the factors associated with students nutritional status. Results: The detection rates of malnutrition, overweight and obesity among primary and secondary school students in Beijing City were 4.7%, 18.0% and 23.8% respectively. The detection rates of malnutrition, overweight and obesity were higher among male students (5.1%, 20.4%, 29.7%) than female students (4.2%, 15.5%, 17.4%) ( χ 2= 12.23, 101.71, 526.99, P <0.01). The detection rate of obesity was higher in the suburbs than urban areas(26.6%, 19.8%), and the detection rate of malnutrition was lower in the suburbs than urban areas (4.2%,5.5%)( χ 2=157.25, 23.61, P <0.01). The results of disordered multi classification Logistic regression showed that the related factors for malnutrition, overweight and obesity were gender, residence, moderate to vigorous exercise ≥60 min per day and lack of sleep( OR =1.70, 1.88,2.48; 1.14, 0.87, 0.67; 0.85, 0.92, 0.81 ; 0.83, 1.08, 1.07); frequency of fried food intake daily was a related factor for overweight ( OR =0.70); whether eating breakfast daily or not was a related factor for overweight and obesity ( OR =0.91, 0.84); academic level (middle and high school) was a related factor for malnutrition and obesity ( OR =1.38, 1.37; 0.77, 1.40)( P <0.05). Conclusions The problem of overweight and obesity among primary and secondary school students in Beijing City continues to be serious, especially among boys and suburban areas. It is recommended that society, schools, families and individuals should work together to improve the nutritional status of primary and secondary school students by adopting a graded and classified approach.

Objective: To understand the trend of changes of hygiene status in the teaching environment among primary and secondary schools in Beijing City during 2016-2020, so as to provide basis for further improving the teaching environment and campus hygiene conditions in primary and secondary schools. Methods: A proportional systematic sampling method covered over 50% of schools selected annually in Beijing from 2016 to 2019, and 34% were selected in 2020. Two representative classrooms were selected from each selected school for testing based on their structure and other factors, with 6 196 classrooms supervised, from 2016 to 2020,1 330,1 312,1 384,1 322,848 classrooms were monitored for each year. Results: From 2016 to 2020, the overall lighting qualification rate of classrooms (lighting coefficient 72.8%, window to floor area ratio 41.8%, rear wall reflectance ratio 42.2%, blackboard reflection ratio 37.4%), the overall qualification rate of average blackboard illumination and uniformity (50.6%, 34.9 %), and the overall qualification rate of desk and chair allocation (58.6%) were all below 80%. The overall qualification rate of per capita classroom area (87.5%), blackboard size (83.2%), average desk illumination ( 80.1% ), average desk illumination and uniformity (82.9%), the distance between lamp and desk (99.1%), carbon dioxide ( 86.6% ), temperature (84.9%), and noise (96.6%) were all above 80%. The following indicators, blackboard size, the distance between lamp and desk, average blackboard illumination, lighting coefficient, blackboard reflectance, rear wall reflectance, carbon dioxide, temperature, and noise ( χ 2=78.38, 9.71, 11.76, 320.59, 37.63, 58.45, 236.45, 1 347.56, 101.97), had statistically significance between years. Among those indicators, the qualified rates of blackboard size, blackboard reflectance, lighting coefficient, and noise had been increasing year by year ( χ 2 trend =69.98, 15.82, 240.02, 5.77) ( P <0.05). The qualified rates of per capita classroom area, window to floor area ratio, and blackboard reflection ratio in primary schools (81.6%, 39.8%, 36.3%) were all lower than those in secondary schools (94.9%, 44.5%, 40.3%) ( χ 2=246.32, 12.03, 10.51, P <0.05). The qualified rates of blackboard size, average blackboard illumination, average blackboard illumination and uniformity, and desk and chair allocation (89.3%, 55.6% , 36.0%, and 60.2%) were all higher than those in secondary schools (75.4%, 44.1%, 33.3%, and 56.5%) ( χ 2=209.33, 78.41, 4.44, 8.22) ( P <0.05). The qualified rates of average desk illumination and uniformity, average blackboard illumination, rear wall reflectance ratio, desk and chair allocation, carbon dioxide, temperature, and noise indicators in urban area (82.9%, 84.1% , 51.9%, 45.0%, 60.9%, 91.2%, 89.5%, 97.8%) were all higher than those in suburban area (77.3%, 81.7%, 49.2%, 39.5%, 56.3%, 82.3%, 80.4%, 95.5%) ( χ 2=31.16, 6.28, 4.36, 16.40, 13.39, 105.29, 98.23, 24.66， P <0.05). The qualified rates of the distance between lamp and desk, lighting coefficient, window to floor area ratio, blackboard size, blackboard reflection ratio, average blackboard illumination and uniformity, and per capita classroom area in urban areas (98.8%, 65.2%, 34.3%, 76.7%, 35.9%, 30.1%, 84.6%) were all lower than those in suburban areas (99.4%, 81.4%, 49.8%, 89.7%, 40.2%, 39.6%, 90.3%) ( χ 2=6.80, 171.67, 132.43, 188.46 , 12.45, 60.28, 44.82) ( P <0.05). Conclusions The main problems in the teaching environment of schools in Beijing are classroom lighting, as well as desk and chair allocation. The findings suggest technical rationality and operability of relevant standard should be considered when under revision, and standard training and supervision management should be strengthened, with the aim of teaching environment improvement.

Objective: The study was aimed at exploring the latent classes and factors influencing middle school students health risk behaviors in Beijing, so as to provide a scientific basis for determining key intervention targets and formulating relevant intervention measures. Methods: A questionnaire survey was conducted among 17 730 junior middle school, senior high school and vocational high school students in 16 districts of Beijing from October to December 2022. Six types of health risk behaviors were assessed with latent class analysis, including unhealthy diet, lack of exercise, unintentional harm, intentional harm, substance abuse and Internet addiction behavior. Results: The latent classes of health risk behavior among middle school students in Beijing were divided into three classes:high risk behavior (961 participants, 5.42%), low lack of exercise/high intentional injury (1 099 participants, 6.20%), and low risk behavior (15 670 participants, 88.38%). Disordered multiple Logistic regression analysis indicated that middle school students who were male ( OR =1.45), in high school ( OR =2.00), had other family types ( OR =1.90), possibly had depressed feelings ( OR =2.27), had depressed feelings ( OR =6.18), or were absent from school because of illness in the past year ( OR =1.79) were more likely to be in the high risk than the low risk behavior group. Moreover, middle school students who were male ( OR =2.30), had an extended family ( OR =1.18), had a reorganized family ( OR =1.70), had other family types ( OR =1.94), possibly had depressed feelings ( OR =3.10), had depressed feelings ( OR =4.91), had taken sick leave in the prior 2 weeks ( OR =1.54), or had absence from school because of illness in the past year ( OR =1.71) were relatively more likely to be in the low lack of exercise or high intentional injury group ( P <0.05). Conclusion Clear latent classes of health risk behaviors among middle school students are found to be present in differing proportions in Beijing. Relevant departments should take targeted intervention measures in a timely manner to reduce the occurrence of health risk behaviors among middle school students.

Objective: To analyze the status of health risk behaviors among middle school students in Beijing City from 2018 to 2022, in order to provide reference for scientific and effective intervention. Methods: Using multi stage stratified cluster random sampling method,data of student health and associated factors monitoring among 84 712 middle school students from 16 districts of Beijing during 2018 to 2022 were compared regarding the differences of health risk behaviors among students in different groups by Chi quare test. And their change trends were evaluated by annual percentage change (APC). Results: In the five surveys during 2018 to 2022,reporting rates of unhealthy diet, unintentional injury, intentional injury, substance abuse and Internet addiction (only in 2018 and 2020) behaviors were higher in boys than in girls ( χ 2=4.91-297.52, P ＜0.05).Reporting rate of physical inactivity behavior in girls was higher than that in boys ( χ 2=56.49-160.88, P ＜0.05). Reporting rates of unhealthy diet, physical inactivity, unintentional injury (except 2021), substance abuse and Internet addiction (only in 2018 and 2019) behaviors were the highest in vocational high school, followed by general high school, and the lowest in junior middle school ( χ 2=23.30-1 285.98, P ＜0.01). Intentional injury behavior was highest in junior high school, followed by vocational high school, and lowest in general high school ( χ 2=96.18-378.32, P ＜0.01).Reporting rate of Internet addiction (2020-2022) behavior was highest in general high school, followed by vocational high school, and lowest in junior high school ( χ 2=16.93-60.11, P＜0.01). Reporting rates of unhealthy diet, intentional injury (2020 and 2022) and substance abuse (except 2018) behaviors were higher in suburban areas than in urban areas (χ 2=6.70-117.56, P＜0.05). Reporting rates of physical inactivity, unintentional injury, intentional injury (2018 and 2019) and Internet addiction behaviors were higher in urban areas than in suburban areas (χ2=3.90-130.80, P＜0.05). Standardized rates of unintentional injury, intentional injury, substance abuse and Internet addiction behaviors showed a statistically significant downward trend from 2018 to 2022 (APC=-14.16, -13.43, -16.03, -8.48, t =-6.94, -4.46, -11.98, -4.36, P ＜0.05). Conclusions During 2018-2022, unintentional injury, intentional injury, substance abuse and Internet addiction behaviors of middle school students in Beijing City have improved, and the reporting rates of unhealthy diet and physical inactivity behaviors are high and don t show a downward trend. Efforts should be made to strengthen intervention in unhealthy diet and physical inactivity behaviors among middle school students, in order to reduce the occurrence of health risk behaviors.

Objective: To analyze the current status and related factors of comorbidity of myopia, obesity, and depression symptoms among middle school students in Beijing, so as to provide a basis for comprehensive public health interventions for common diseases. Methods: Through stratified cluster random sampling in October 2022, a total of 11 262 junior high school, senior high school, and vocational high school students in 16 districts of Beijing were surveyed with self administered questionnaires, physical examinations and visual acuity examinations. The χ 2 test and binary Logistic regression model were used to analyze group differences in the comorbidity of myopia, obesity and depression symptoms and factors influencing the comorbidity. Stratified analysis was applied to analyze the associations between health risk behaviors and the comorbidity. Results: The detection rate of comorbidity of myopia, obesity, and depression symptoms among middle school students in Beijing was 3.35%, the comorbidity rate among vocational high school students (4.61%) was higher than that in junior high school students (2.80%) and senior high school students (3.41%). The comorbidity rate was higher among students in suburban areas (3.66%) than that in urban areas (2.92%), and the differences was statistically significant ( χ 2=15.02, 4.63, P <0.05). Binary Logistic regression analyses indicated that middle school students with poor dietary behaviors ( OR =1.59) and excessive screen time ( OR =1.70) were associated with elevated risk of comorbidity of myopia, obesity, and depression symptoms. Both boys and girls with poor dietary behaviors ( OR =1.63, 1.69) and excessive screen time ( OR =1.45, 2.23) had elevated likelihood of comorbidity of myopia, obesity and depression symptoms. Students in junior high school and senior high school with poor dietary behaviors ( OR =2.16, 1.47) and excessive screen time ( OR =2.20, 1.63 ) had elevated likelihood of comorbidity of myopia, obesity, and depression symptoms ( P <0.05). Conclusions The current status of comorbidity of myopia, obesity, and depression symptoms among middle school students in Beijing is concerning. Schools and parents should work together to guide students to develop healthy behaviors such as balanced diet and moderate video, in order to achieve the goal of controlling myopia, obesity and depression symptoms.

Objective: To investigate the comorbidity of screening myopia and scoliosis among primary and secondary school students in Beijing from 2019 to 2022 and its influencing factors, in order to provide new ideas for comprehensive prevention and control of myopia and scoliosis in children and adolescents. Methods: From 2019 to 2022, 34 923, 34 321, 36 008 and 35 598 primary and secondary school students in Beijing were selected by stratified cluster random sampling method, and visual acuity examination, scoliosis examination and questionnaire survey were conducted on them. Chisquare test was used to analyze the intergroup differences between screening myopia and scoliosis among primary and secondary school students, and the correlation factors between screening myopia and scoliosis were analyzed by multivariate Logistic regression. Results: From 2019 to 2022, the prevalence of screening myopia increased by year,while scoliosis decreased by year, and the comorbidity rate in 2022 (0.69%) decreased by 1.62% compared with 2019 (2.31%). In 2022, screening myopia with scoliosis rates (0.98%) than urban suburbs (0.50%), high school students (1.65%) >professional high school students (1.21%) >junior middle school students (0.76%) >primary school students (0.22%) (χ2=28.97, 153.55, P<0.01). The results of multivariate Logistic analysis found that insufficient sleep time and parents did not limit the use of electronic screen time were the risk factors for screening myopia and scoliosis [OR(95%CI)=1.59(1.20-2.12), 1.34(1.02-1.76), P<0.05]. Teachers often or always remind that reading and writing posture and one hour or more of moderateintensity physical activity every day were protective factors for screening myopia and scoliosis [OR(95%CI)=0.70(0.52-0.96), 0.56(0.34-0.92), P<0.05]. Conclusions The comorbidity of acadmic screening myopia and scdiosis is not optimistic in Beijing. Attention should be paid to the reading and writing posture and related behavioral habits of children and adolescents, and ensure that children in each school section have sufficient sleep time, so as to prevent the occurrence and development of screening myopia and scoliosis.

BACKGROUND:Tissue engineering is considered an ideal treatment for growth plate regeneration.However,most of the current research on regenerative tissue engineering is the traditional scaffold-based strategy.As the limitations of traditional scaffolds are gradually revealed,the research direction is gradually diversifying. OBJECTIVE:To summarize the application of scaffold-based and scaffold-free strategies in the treatment of growth plate cartilage regeneration and their respective advantages and disadvantages. METHODS:The relevant articles were searched from PubMed,Wiley,and Elsevier.The search terms were"growth plate injury,regeneration,tissue engineering,scaffold,scaffold-free,biomimetic,cartilage"in English.The time was limited from 1990 to 2023.Finally,104 articles were included for review. RESULTS AND CONCLUSION:The biomimetic strategy is to reduce the cell composition,biological signals and unique mechanical properties of each region to the greatest extent by simulating the unique organizational structure of the growth plate,so as to build a biomimetic microenvironment that can promote tissue regeneration.Therefore,the design of a biomimetic scaffold is to simulate the original growth plate as far as possible in terms of composition,structure and mechanical properties.Although some results have been achieved,there is still the problem of the unstable regeneration effect.The scaffold-free strategy believes that the limitations of scaffolds will have adverse effects on regenerative therapy.Therefore,the design of scaffold-free constructs relies as much as possible on the ability of cells to generate and maintain extracellular matrix without interfering with cell-cell signals or introducing exogenous substances.However,there are some problems,such as poor stability,low mechanical strength and greater difficulty in operation.Biomimetic strategy and scaffold-free strategy have different emphases,advantages and disadvantages,but they both have positive effects on growth plate cartilage regeneration.Therefore,subsequent studies,whether adopting a biomimetic strategy or a scaffold-free strategy,will focus on the continuous optimization of existing technologies in order to achieve effective growth plate cartilage regeneration therapy.

Objective:To investigate the incidence of thyroid dysfunction in patients with chronic kidney disease and analyze the influencing factors.Methods:One hundred and ninety-eight patients with chronic kidney disease who were treated in Chronic Disease Management Department of the First Affiliated Hospital of Hunan University of Traditional Chinese Medicine from Apr. 2021 to Apr. 2022 were selected, including 71 patients with abnormal thyroid function and 127 patients with normal thyroid function. The differences in TT3, FT3, TT4, FT4, and TSH between patients with abnormal thyroid function and those with normal thyroid function were analyzed. At the same time, the abnormal thyroid function of patients with different clinical characteristics and the influencing factors were analyzed. The intergroup differences were analyzed using t-test or χ2-test, and the influencing factors were analyzed using logistic regression analysis. Results:In one hundred and ninety-eight patients with chronic kidney disease, thyroid function abnormality occurred in 71 patients (35.86%), including two or more abnormal thyroid function indicators in 35 patients (49.30%). The total triiodothyronine (TT3), free triiodothyronine (FT3), total thyroxine (TT4) and free thyroxine (FT4) in patients with abnormal thyroid function were (1.02 ± 0.29) nmol/mL, (3.03 ± 0.88) pmol/L, (77.93 ± 20.02) nmol/mL and (11.02 ± 1.95) pmol/L respectively, which was significantly lower in patients with normal thyroid function (1.32±0.25) nmol/mL, (4.20±0.92) pmol/L, (93.30±19.28) nmol/mL and (13.54±1.82) pmol/ ( P<0.05), while thyroid stimulating hormone (TSH) was (3.14 ± 0.96) mIU/L, which was significantly higher than that in patients with normal thyroid function (1.84±0.89) mIU/L ( P<0.05). The incidence of thyroid dysfunction in female patients was 50.59% (43/85), It was significantly higher than 24.78% (28/113) of male patients (P <0.05) ; The incidence of thyroid dysfunction in patients aged 60 years was 49.55% (55/111), It was significantly higher than 18.39% (16/87) of the patients aged <60 years ( P<0.05) ; The incidence of thyroid dysfunction in patients with 1-year duration of disease was 71.43% (30/42), It was significantly higher than 25.28% (41/156) of patients with a course of disease <1 year ( P<0.05) ; The incidence of thyroid dysfunction in patients with clinical stage G 4 to 5 was 50.62% (41/81), It was significantly higher than 25.64% (30/117) of patients in G1~3 stages ( P<0.05) ; The incidence of thyroid dysfunction in patients with diabetes was 74.36% (29/39), This was significantly higher than 26.42% (42/159) in patients without diabetes mellitus ( P<0.05). Logistic regression analysis showed that gender, age, course of disease and clinical stage were the influencing factors of thyroid dysfunction in patients with chronic kidney disease ( P<0.05) . Conclusion:A high proportion of patients with chronic kidney disease have abnormal thyroid function, which is affected by the patient's sex, age, course of disease and clinical stage,clinical attention should be paid to targeted intervention to prevent the incidence of thyroid dysfunction in chronic kidney disease population.