Objective To investigate the relationship between impaired fasting glucose(IFG) and the distribution of body fat in adolescents.Methods Stratified cluster sampling was used to select 3874 adolescents aged 13-18 years for this cress-sectional study.Measurements included height,weight,waist circumference,hip circumference and fasting plasma glucose (FPG).Family history of diabetes was determined by using a serf-administered questionnaire.Participants were divided into normal fasting glucose group(FPG＜5.6 mmol/L,n=3738) and impaired fasting glucose group (5.6 mmol/L≤FPG ＜ 7.0 mmoL/L,n=136) according to their FPG levels. Results (1) After adjusting for age and sex using covariance analysis,the impaired fasting glucose group showed increased levels of body mass index,weight circumference,waist/hip ratio,waist/height ratio,as compared to the normal fasting glucose group (P＜ 0.05).(2) After the age and gender were adjusted,body mass index,weight circumference,waist/hip ratio and waist/height ratio were positively correlated with FPG level (P＜0.05).Among the partial relation coefficients, that between waist/height ratio and FPG(r'=0.0925) was the highest (3) In multiple regression analyses,age (β=-0.102,P＜0.05),family history of diabetes (β=0.186,P＜0.05) and waist/height ratio (β=0.842,P＜0.05) were consistently associated with FPG.Conclusion Central obesity was an important predictor of IFG in adolescents.Waist/height ratio may be an useful index of central obesity and an important predictor of IFG in adolescents.

Objective To explore the best cut-point of waist-to-heisht ratio (WHtR) for identifying metabolic syndrome(MS)in adolescents.Methods A cross-sectional study was conducted in 4 507 adolescents aged 13-18 years in Qinhuangdao.Receiver operating characteristic (ROC) curve analysis was employed to determine the optimal WHtR cut-point for detecting MS.Results The prevalences of MS were higher among higher WHtR in both boys and girls.Odds ratios for MS significantly increased from the WHtR≥0.45 in boys(OR =13.85,95%CI 4.08-46.97)and in girls (OR=12.42,95%CI 2.62-58.96,P<0.01).The ROC curve analysis showed that the optimal WHtR cut-point was 0.45 in boys with the sensitivity of 89.4%and specificity of 81.4%.and in girls with sensitivity of 90.3%and specificity of 86.5%.Conclusion There is a significant correlation between WHtR and MS.Optimal WHtR cut-point for predicting MS is 0.45.

This study aims to construct C57/B6-L and A549 cell lines that stably overexpress circu-lar RNA LAMP3(circLAMP3),laying the foundation for further research on the biological func-tions of circLAMP3.Total RNA was extracted and reverse transcripted into cDNA from C57/B6-L and A549 cells to amplify the full-length sequence of circLAMP3.Then,the fragments of cir-cLAMP3 were ligated into pLC5-ciR vector to obtain pLC5-Mouse-circLAMP3 and pLC5-Human-circLAMP3 recombinant plasmids.The lentiviruses expressing circLAMP3 were packaged on tran-sient transfected HEK293T cells.C57/B6-L and A549 cells were infected with lentiviruses to gen-erate cell lines overexpressing circLAMP3 through puromycin screening.To verify the overexpres-sion efficiency of circLAMP3 of cell lines,we performed the fluorescence microscopy,PCR amplifi-cation,quantitative PCR(qPCR),and Sanger sequencing experiments.The results indicated that the overexpression plasmids of pLC5-Mouse-circLAMP3 and pLC5-Human-circLAMP3 were suc-cessfully constructed.Strong green fluorescence was observed under a fluorescence microscopy.C57/B6-L and A549 cell lines showed a significant increase in the expression of circLAMP3 by PCR and qPCR methods.Sanger sequencing results showed that the junction site of circLAMP3 was correct.This study successfully constructed C57/B6-L and A549 cell lines overexpressing circLAMP3,providing biomaterials for further exploration of the biological function of circLAMP3 in influenza virus replication.