Mediation effect of sleep time on the association between outdoor activity and myopia in Chinese children and adolescents: a cross-sectional study.

BACKGROUND: This study aimed to assess the association between outdoor activity and myopia among children and adolescents and investigate whether sleep time could mediate this relationship. METHODS: This cross-sectional study was performed on students aged 4-16 years in China, from August 2021 to January 2022. Outdoor activity was assessed by the Assessment Questionnaire of Exposure to Sunlight Activities for Students (AQESAS). Binary logistic regression combined with the mediation analysis was used to analyze the association of AQESAS with myopia and the mediating effect of sleep time on this relationship. RESULTS: The prevalence of myopia was 53.51% (N = 1609). Multivariate logistic regression analysis showed that more sleep time (OR = 0.794, 95%CI: 0.707-0.893) and a higher score of AQESAS (OR = 0.989, 95%CI: 0.981-0.996) were significantly associated with a decreased risk of myopia. Mediation analysis revealed that sleep time plays a mediating role in the association between outdoor activity and myopia (ACME = -0.0006, P < 0.001), and the mediation proportion was 19.7%. CONCLUSION: Outdoor activity affects myopia directly and indirectly through sleep time. The result suggested that children may be able to reduce the risk of myopia by promoting sleep through increased awareness of outdoor activity and exposure to sunlight.

Serum folate mediates the associations of MTHFR rs1801133 polymorphism with blood glucose levels and gestational diabetes mellitus in Chinese Han pregnant women.

This study aimed to explore the mediation effects of one-carbon metabolism (OCM) related nutrients on the association between MTHFR rs1801133 polymorphism and gestational diabetes mellitus (GDM). Folate, vitamin B12 and homocysteine (Hcy) were measured in the serum of 1254 pregnant women. Linear and logistic regressions were used to estimate the associations of OCM nutrients and MTHFR rs1801133 polymorphism with blood glucose levels and GDM risk. Mediation analysis was applied to test the mediation effects of folate, vitamin B12 and Hcy on the association of MTHFR rs1801133 polymorphism with blood glucose concentrations and GDM. Pregnant women with MTHFR rs1801133 CC genotype had higher serum folate (10·75 v. 8·90 and 9·40 ng/ml) and lower serum Hcy (4·84 v. 4·93 and 5·20 µmol/l) than those with CT and TT genotypes. Folate concentrations were positively associated with fasting plasma glucose (FPG), 1-h plasma glucose (1-h PG), 2-h plasma glucose (2-h PG) and GDM risk. Vitamin B12 levels were negatively correlated with FPG and GDM. Although no direct association was found between MTHFR rs1801133 genotypes and GDM, there were significant indirect effects of MTHFR rs1801133 CC genotype on FPG (ß: 0·005; 95 % CI: 0·001, 0·013), 1-h PG (ß: 0·006; 95 % CI: 0·001, 0·014), 2-h PG (ß: 0·007; 95 % CI: 0·001, 0·015) and GDM (ß: 0·006; 95 % CI: 0·001, 0·014) via folate. In conclusion, serum folate mediates the effect of MTHFR rs1801133 on blood glucose levels and GDM. Our findings potentially provide a feasible GDM prevention strategy via individualised folate supplementation according to the MTHFR genotypes.

Mental health difficulties and related factors in Chinese children and adolescents during the COVID-19 pandemic: a cross-sectional study.

OBJECTIVE: To examine the mental health status and related factors in children and adolescents, and to assess age groups and sexes differences in factors influencing mental health. METHODS: This cross-sectional study was performed on Chinese children aged 6-18 years from November 2021 to January 2022. Mental health difficulties were accessed by the Strengths and Difficulties Questionnaire. Multivariate logistic regression was used to analyze factors associated with mental health status. Multiple linear regression was used to evaluate factors associated with the scores of the Strengths and Difficulties Questionnaire. RESULTS: The prevalence of mental health difficulties was 12.98% (n =1348). Age (OR, 0.909, [95%CI, 0.830-0.996]), sex (OR, 1.424, [95%CI, 1.033-1.963]) and screen time on weekdays ("≥2" h/d vs "< 1" h/d: OR, 2.001, [95%CI, 1.300-3.080]) were related factors for mental health difficulties. For children (year ≤ 12), the strongest related factor for mental health difficulties was screen time on weekdays ("≥ 2" h/d vs "< 1" h/d: OR, 1.821 [95%CI, 1.203-2.755]). The risk of mental health difficulties in females with ≥ 2 h/d screen time on weekends was 3.420 times higher than those with < 1 h/d (OR, 3.420, [95%CI, 1.923-6.081]). CONCLUSION: The prevalence of mental health difficulties among children and adolescents was relatively high. The lower age, female sex and excessive screen time were associated with a higher risk of mental health difficulties. The factors influencing mental health varied by different age groups and sexes. Thus, specific measures for different age groups and sexes should be adopted to mitigate the impact.

Associations of Dietary Zinc-Vitamin B6 Ratio with All-Cause Mortality and Cardiovascular Disease Mortality Based on National Health and Nutrition Examination Survey 1999-2016.

Previous studies have suggested a possible association among dietary zinc and vitamin B6 intake and CVD mortality and all-cause mortality. However, evidence on the association of dietary zinc and vitamin B6 intake and their interactions with CVD mortality and all-cause mortality remains unclear. This prospective study utilized data from the US National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016. After a median follow-up of 10.4 years, 4757 deaths were recorded among 36,081 participants. Higher dietary zinc intake levels (≥9.87 mg/day) were associated with lower CVD mortality (hazard ratio (HR) = 0.85, 95% confidence interval (CI): 0.83−0.87). Vitamin B6 intake levels (≥1.73 mg/day) were associated with lower CVD mortality (HR = 0.91, 95% CI: 0.86−0.96) and all-cause mortality (HR = 0.91, 95% CI: 0.90−0.93). Higher dietary zinc intake and higher vitamin B6 intake were associated with a lower risk of CVD mortality, with an interaction between dietary zinc intake levels and vitamin B intake levels (LZLV group (HR, CI): 1.21,1.12−1.29; LZHV group (HR, CI): 1.42, 1.34−1.50; LZHV group (HR, CI): 1.28, 1.14−1.45; HZHV group (HR, CI): ref). There was also a J-type association (p for nonlinear < 0.001) between the dietary zinc−vitamin B6 ratio and CVD mortality, with a high dietary zinc−vitamin B6 ratio increasing the risk of CVD mortality (HR = 1.27, 95% CI: 1.19−1.35), whereas a moderate dietary zinc−vitamin B6 ratio appeared to be beneficial for CVD mortality. These results suggest that increasing the appropriate proportion of dietary zinc and vitamin B6 intake is associated with a lower risk of CVD mortality. Furthermore, precise and representative studies are needed to verify our findings.

Association between Systemic Immunity-Inflammation Index and Hyperlipidemia: A Population-Based Study from the NHANES (2015-2020).

The systemic immunity-inflammation index (SII) is a novel inflammatory marker, and aberrant blood lipid levels are linked to inflammation. This study aimed to look at the probable link between SII and hyperlipidemia. The current cross-sectional investigation was carried out among people with complete SII and hyperlipidemia data from the 2015-2020 National Health and Nutrition Examination Survey (NHANES). SII was computed by dividing the platelet count × the neutrophil count/the lymphocyte count. The National Cholesterol Education Program standards were used to define hyperlipidemia. The nonlinear association between SII and hyperlipidemia was described using fitted smoothing curves and threshold effect analyses. A total of 6117 US adults were included in our study. A substantial positive correlation between SII and hyperlipidemia was found [1.03 (1.01, 1.05)] in a multivariate linear regression analysis. Age, sex, body mass index, smoking status, hypertension, and diabetes were not significantly correlated with this positive connection, according to subgroup analysis and interaction testing (p for interaction > 0.05). Additionally, we discovered a non-linear association between SII and hyperlipidemia with an inflection point of 479.15 using a two-segment linear regression model. Our findings suggest a significant association between SII levels and hyperlipidemia. More large-scale prospective studies are needed to investigate the role of SII in hyperlipidemia.

Effect of short-term exposure to ambient air pollutants on non-accidental mortality in emergency department visits: a time-series study.

Objectives: Exposure to air pollution has been linked to an increased risk of premature mortality. However, the acute effects of air pollution on the risk of non-accidental mortality have not been extensively researched in developing countries, and the findings thus far have been inconsistent. Therefore, this study aimed to examine the association between short-term exposure to six pollutants (PM2.5, PM10, SO2, NO2, O3, and CO) and non-accidental mortality in Beijing, China. Methods: Daily data on non-accidental deaths were gathered from 1 January 2017 to 31 December 2018. Air pollution data for the same period were collected from 35 fixed-site air quality monitoring stations in Beijing. Generalized additive models (GAM) based on Poisson regression were used to investigate the association between non-accidental mortality in emergency department visits and the daily average levels of air pollutants. Results: There were 8,676 non-accidental deaths recorded during 2017-2018. After sensitivity analysis, short-term exposure to air pollutants, particularly gaseous pollutants, was linked to non-accidental mortality. Specifically, for every 10 µg/m3 increase (5 µg/m3 in SO2, 0.5 mg/m3 in CO) of SO2 (lag 04), NO2 (lag 04), O3 (lag 05), and CO (lag 04), the relative risk (RR) values were 1.054 (95% CI: 1.009, 1.100), 1.038 (95% CI: 1.013, 1.063), 1.032 (95% CI: 1.011, 1.054), and 1.034 (95% CI: 1.004, 1.066), respectively. In terms of causes of death, short-term exposure to NO2, SO2, and O3 increased the risk of circulatory mortality. Further stratified analysis revealed that the stronger associations were presented in females for O3 while in males for CO. People aged 65 and over were strongly associated with ambient air pollution. Conclusions: Our study showed that ambient air pollutants were associated with non-accidental mortality. Our findings suggested that efforts to control gaseous pollution should be stepped up, and vulnerable groups should be the focus of health protection education.

Serum microRNA miR-206 is decreased in hyperthyroidism and mediates thyroid hormone regulation of lipid metabolism in HepG2 human hepatoblastoma cells.

The actions of thyroid hormone (TH) on lipid metabolism in the liver are associated with a number of genes involved in lipogenesis and lipid metabolism; however, the underlying mechanisms through which TH impacts on lipid metabolism remain to be elucidated. The present study aimed to investigate the effects of hyperthyroidism on the serum levels of the microRNA (miR) miR­206 and the role of miR­206 on TH­regulated lipid metabolism in liver cells. Serum was obtained from 12 patients diagnosed with hyperthyroidism and 10 healthy control subjects. Human hepatoblastoma (HepG2) cells were used to study the effects of triiodothyronine (T3) and miR­206 on lipid metabolism. Expression of miR­206 in serum and cells was determined by reverse transcription­quantitative polymerase chain reaction analysis. Lipid accumulation in HepG2 cells was assessed with Oil Red O staining. Suppression or overexpression of miR­206 was performed via transfection with a miR­206 mimic or miR­206 inhibitor. Serum miR­206 was significantly decreased in patients with hyperthyroidism compared with euthyroid controls. Treatment of HepG2 cells with T3 led to reduced total cholesterol (TC) and triglyceride (TG) content, accompanied by reduced miR­206 expression. Inhibition of endogenous miR­206 expression decreased intracellular TG and TC content in HepG2 cells. By contrast, overexpression of miR­206 in HepG2 partially prevented the reduction in TG content induced by treatment with T3. In conclusion, serum miR­206 expression is reduced in patients with hyperthyroidism. In addition, miR­206 is involved in T3­mediated regulation of lipid metabolism in HepG2 cells, indicating a role for miR­206 in thyroid hormone­induced disorders of lipid metabolism in the liver.

Adipokines and free fatty acids regulate insulin sensitivity by increasing microRNA-21 expression in human mature adipocytes.

Obesity is a global public health concern and may lead to a variety of complications. Previous studies have indicated that adipokines and energy­source materials contribute to obesity and obesity­associated insulin resistance. MicroRNAs (miRs) are endogenous 20­ to 25­nucleotide non­coding RNAs associated with fat metabolism. It has been indicated that miR­21 is associated with adipogenesis and metabolic syndrome. In the present study, the expression of miR­21 in human mature adipocytes was analyzed using reverse transcription quantitative­polymerase chain reaction following treatment with adipokines, including tumor necrosis factor (TNF)­α, interleukin (IL)­6, leptin, resistin and energy source materials, including free fatty acids (FFAs) and glucose. The current study demonstrated that the expression of miR­21 in human mature adipocytes was upregulated following treatment with TNF­α, IL­6, leptin, resistin and FFAs. However, low­ and high­glucose did not have an effect on miR­21 expression. These results confirmed that TNF­α, IL­6, leptin, resistin and FFAs may contribute to obesity and obesity­associated insulin resistance via upregulating miR­21 in human mature adipocytes. Therefore, miR­21 may be a key regulatory factor of obesity and obesity­associated insulin resistance, and represents a potential therapeutic target for the treatment of these disorders.

MicroRNA-100 promotes migration and invasion through mammalian target of rapamycin in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the predominant histologic subtype of esophageal cancer and is characterized by a high mortality rate and geographic differences in incidence. microRNAs (miRNAs) are small, non-coding RNAs that play important roles in the regulation of genes associated with cancer development and progression. In the present study, we demonstrated that microRNA-100 (miR­100) demonstrated markedly lower expression in the ESCC tissues as validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Furthermore, we found that the downregulation of miR-100 was significantly correlated with the status of lymph node metastasis in the 34 ESCC patients. Next, we investigated the role and mechanism of miR-100 in ESCC cells and found that miR-100 modulated the migration and invasion but not the apoptosis and proliferation of ESCC cells in vitro. We further demonstrated that miR-100 directly targeted the mTOR 3'UTR and repressed the expression of mTOR, a tumor-related gene. Similarly, miR-100 has been reported as a tumor suppressor by controlling cell migration and invasion, as it can target mTOR genes. These results provide insight into the potential mechanisms of miR-100 in the pathogenesis of ESCC.