ABSTRACT
Objective@#To investigate the longitudinal association of plasma Irisin concentrations with changes in blood pressure (BP) levels among children,and to assess the moderating effect of physical activity (PA) or sedentary behavior (SB) on the relationship between Irisin levels and BP.@*Methods@#Based on a cohort study, a cluster sampling method was used to select 3 651 school aged children from five schools in Guangzhou in 2017 at the baseline survey and follow up in 2019. Both at baseline and during follow up, PA and SB were assessed by validated questionnaires, and BP levels were measured by an electronic sphygmomanometer. A final sample of 521 children were enrolled based on the PA and SB at baseline. Plasma Irisin concentrations were measured by ELISA at baseline. Logistic regression analysis was recruited for exploring the associations of plasma Irisin concentrations with changes in BP. Moderating effects of PA and SB on the relationship between Irisin concentrations and BP were estimated using stratified analysis.@*Results@#Logistic regression analysis indicated that there was no significant association between Irisin concentrations and changes in BP levels among children ( OR =0.98, P >0.05). After stratification for SB, Irisin levels in the low SB subgroup were inversely associated with changes in diastolic blood pressure ( OR=0.87, 95%CI=0.77-0.98, P =0.02). In addition, SB level had a moderating effect on the relationship between Irisin levels and the DBP changes ( P =0.01).@*Conclusion@#Increased Irisin concentration is associated with the decrease of DBP level among low SB children. Furthermore, SB level shows moderating role in the relationship between Irisin concentrations and changes in DBP levels.
ABSTRACT
Objective @#To investigate the effect of different concentrations of MTA on the proliferation and differentiation of stem cells from the apical papilla (SCAP) and the potential of the SCAP to differentiate into odontoblasts.@*Methods@#SCAP were cultured in different concentrations of mineral trioxide aggregate（MTA）. MTA experimental group with concentration of 0.01 mg/mL, 0.02 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 1 mg/mL, 2 mg/mL, 10 mg/mL and 20 mg/mL were prepared. The number of cells at 1 day, 3 days, 5 days and 7 days were measured via a CCK-8 assay to observe the effect of MTA on SCAP proliferation. Real-time PCR was used to detect the gene expression changes. Cells cultured in alpha MEM culture containing 15% FBS without MTA were set as the control group.@*Results @#When cultured for 1 d, statistically significant differences in the promotion of in vitro proliferation of SCAP were not observed between each MTA experimental group and the control group (P>0.05). When cultured for 3 d, 5 d and 7 d, the 0.01 mg/mL MTA group presented obvious promotion of SCAP proliferation compared with the control group (P<0.05), whereas the 0.02 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 1 mg/mL groups did not presented differences with the control group (P>0.05). The in vitro proliferation of the 2 mg/mL, 10 mg/mL and 20 mg/mL groups was lower than that of the control group (P<0.05). Real-time PCR detection showed that the expression levels of DSPP (t=-11.12, P < 0.05) and Runx2 (t=-10.62, P < 0.05) in the experimental group treated with 0.01 mg/mL MTA for 7 days were higher than those in the control group. @*Conclusion @#The 0.01 mg/mL concentration of MTA significantly promotes the proliferation of SCAP and shows the best ability to induce osteogenic and odontoblast differentiation in the SCAP, whereas high concentrations of MTA inhibited the proliferation of SCAP.