BACKGROUND:Nerve growth factor is a protein that induces nerve growth and regulates biological behaviors such as proliferation and differentiation of mesenchymal stem cells. OBJECTIVE:To investigate the promoting effect of nerve growth factor on chondrogenic differentiation of bone marrow mesenchymal stem cells. METHODS:Rabbit bone marrow mesenchymal stem cells were isolated and cultured,and nerve growth factor was transfected into bone marrow mesenchymal stem cells by lentiviral transfection.The effects of nerve growth factor on the proliferation,migration,hypertrophic differentiation,and chondrogenic differentiation of bone marrow mesenchymal stem cells were detected by CCK-8 assay,cell scratch assay,alizarin red staining,and western blot assay,using the transfected null-loaded virus as control.To further investigate the promoting effect of nerve growth factor on the chondrogenic differentiation of bone marrow mesenchymal stem cells,interleukin 1β was added in bone marrow mesenchymal stem cells transfected with empty virus and nerve growth factor for 14 days.The expression of proteins related to chondrogenic differentiation and hypertrophic differentiation was detected by western blot assay. RESULTS AND CONCLUSION:(1)CCK-8 assay results showed that nerve growth factor had no significant effect on the proliferation of bone marrow mesenchymal stem cells.(2)Compared with the control group,overexpression of nerve growth factor enhanced the migration ability of the cells,and the expression of cartilage-associated proteins type II collagen and SOX9 was up-regulated(P<0.05),while the expression of hypertrophic-associated proteins type X collagen and Runx2 was down-regulated(P<0.05).(3)Compared with the empty virus+interleukin 1β group,the expression of cartilage-associated proteins type II collagen and Sox9 was up-regulated(P<0.05),and the expression of hypertrophy-associated proteins type X collagen and Runx2 was down-regulated after overexpression of nerve growth factor(P<0.05).(4)The results indicated that nerve growth factor could promote the chondrogenic differentiation of bone marrow mesenchymal stem cells.

Objective:To determine the detection rate of myopia among primary and secondary school students in Hunan Province in 2022 and to analyze the influencing factors at both the school and individual levels, thereby providing a scientific basis for developing myopia prevention and control strategies.Methods:From October to November 2022, a multi-stage stratified cluster random sampling method was employed to select students from Year 4 of primary school to Year 3 of senior high school across 14 prefecture-level (autonomous prefecture) cities in Hunan Province for vision screening and questionnaire surveys. A multilevel regression model was utilized to analyze the influencing factors of myopia at both the school and individual levels.Results:A total of 189 343 primary and secondary school students were included in this study. The overall myopia detection rate was 55.56%, with a significantly higher prevalence observed in female students (60.49%) compared to males (51.03%) and in urban students (59.12%) versus those from rural areas (53.50%). A marked upward trend in myopia prevalence was identified with advancing grade levels (trend test χ2=16 246.13, P<0.001). Multilevel regression analysis revealed that at the individual level, female gender, higher grade level, parental myopia history, daily homework duration ≥2 hours after school, improper reading/writing postures, and taking breaks only after more than 15 minutes of near work were associated with an increased risk of myopia. Conversely, adequate sleep duration, outdoor activity ≥2 hours, and outdoor breaks during recess demonstrated protective effects. At the school level, non-compliant blackboard illumination uniformity emerged as a significant risk factor for myopia development. Conclusions:The detection rate of myopia among primary and secondary school students in Hunan Province remains relatively high and is associated with multiple factors at both the school and individual levels. Targeted interventions should be implemented at different levels to mitigate the risk of myopia.

Objective:To determine the detection rate of myopia among primary and secondary school students in Hunan Province in 2022 and to analyze the influencing factors at both the school and individual levels, thereby providing a scientific basis for developing myopia prevention and control strategies.Methods:From October to November 2022, a multi-stage stratified cluster random sampling method was employed to select students from Year 4 of primary school to Year 3 of senior high school across 14 prefecture-level (autonomous prefecture) cities in Hunan Province for vision screening and questionnaire surveys. A multilevel regression model was utilized to analyze the influencing factors of myopia at both the school and individual levels.Results:A total of 189 343 primary and secondary school students were included in this study. The overall myopia detection rate was 55.56%, with a significantly higher prevalence observed in female students (60.49%) compared to males (51.03%) and in urban students (59.12%) versus those from rural areas (53.50%). A marked upward trend in myopia prevalence was identified with advancing grade levels (trend test χ2=16 246.13, P<0.001). Multilevel regression analysis revealed that at the individual level, female gender, higher grade level, parental myopia history, daily homework duration ≥2 hours after school, improper reading/writing postures, and taking breaks only after more than 15 minutes of near work were associated with an increased risk of myopia. Conversely, adequate sleep duration, outdoor activity ≥2 hours, and outdoor breaks during recess demonstrated protective effects. At the school level, non-compliant blackboard illumination uniformity emerged as a significant risk factor for myopia development. Conclusions:The detection rate of myopia among primary and secondary school students in Hunan Province remains relatively high and is associated with multiple factors at both the school and individual levels. Targeted interventions should be implemented at different levels to mitigate the risk of myopia.

Objective:Non-alcoholic fatty liver disease(NAFLD)is a common metabolic disorder in overweight and obese children,and its etiology and pathogenesis remain unclear,lacking effective preventive and therapeutic measures.This study aims to explore the association between whole blood copper,zinc,calcium,magnesium and iron levels and NAFLD in overweight and obese children aged 6 to 17 years,providing a scientific basis for the prevention and intervention of early NAFLD in overweight and obese children. Methods:A cross-sectional study design was used to collect relevant data from overweight and obese children who visited the Hunan Children's Hospital from January 2019 to December 2021 through questionnaire surveys.Fasting blood samples were collected from the subjects,and various indicators such as blood glucose,blood lipid,and mineral elements were detected.All children were divided into an overweight group(n=400)and a NAFLD group(n=202).The NAFLD group was divided into 2 subgroups according to the ALT level:A non-alcoholic fatty liver(NAFL)group and a non-alcoholic steatohepatitis(NASH)group.Logistic regression analysis was used to analyze the association between minerals(copper,zinc,calcium,magnesium,and iron)and NAFLD,NAFL and NASH. Results:A total of 602 subjects were included,of whom 73.6%were male,with a median age of 10(9,11)years,and a body mass index(BMI)of 24.9(22.7,27.4)kg/m2.The intergroup comparison results showed that compared with the overweight group,the NAFLD group had higher levels of age,BMI,diastolic blood pressure(DBP),systolic blood pressure(SBP),triglyceride(TG),low density lipoprotein(LDL),alanine transaminase(ALT)and aspartate aminotransferase(AST),and lower level of high density lipoprotein(HDL).The NAFL group had higher levels of age,BMI,DBP,SBP,ALT,and AST,and lower levels of HDL compared with the overweight group.The levels of age,BMI,DBP,SBP,TG,LDL,ALT,and AST of NASH were higher than those in the overweight group,while the level of HDL was lower than that in overweight group(all P<0.017).After adjusting for a variety of confounders,the OR of NAFLD for the highest quantile of iron was 1.79(95%CI 1.07 to 3.00)compared to the lowest quantile,and no significant association was observed between copper,zinc,calcium,and magnesium,and NAFLD.The subgroup analysis of NAFLD showed that the OR for the highest quantile of iron in children with NAFL was 2.21(95%CI 1.26 to 3.88),while no significant association was observed between iron level and NASH.In addition,no significant associations were observed between copper,zinc,calcium,and magnesium levels and NAFL or NASH. Conclusion:High iron level increases the risk of NAFLD(more likely NAFL)in overweight and obese children,while copper,zinc,calcium,magnesium,and other elements are not associated with the risk of NAFLD in overweight and obese children.

Objective To investigate the infection status of HCV in remunerated blood donors and risk factors in Jiangsu province.Methods A Cross-sectional study was conducted among people aged ＞50 years.Questionnaires were used to collect the information about their demographic characteristics and risk behaviors,and venous blood samples were collected from them to detect HCV anti-body,HCV-RNA and other biochemical indicators.EpiData and Stata were used for data entry and statistical analysis.Results The overall HCV sero-prevalence rates were 22.55％ and 61.05％ among remunerated blood donors.Data firom multiple stepwise regression analysis showed that alanine aminotransferase (ALT) (adjusted OR=1.38,95％CI:1.18-1.62) and aspartate aminotransferase (AST) (adjusted OR=l.30,95％CI:1.10-1.54) were associated with the outcomes of HCV infection,and fasting plasma glucose (adjusted OR=1.17,95％CI:1.01-1.35) were associated with HCV RNA viral loads.Conclusion The prevalence of HCV infection in remunerated blood donors was high,clinical ALT,AST and fasting plasma glucose levels were associated with the risk for HCV infection and HCV RNA viral load.