RESUMO
Objective To explore the association between serum trace element levels in early pregnancy and gestational dia-betes mellitus(GDM),and the mediating effect of bile acid metabolism changes in this association.Methods A nested case-con-trol study was designed based on the Guangxi Zhuang Birth Cohort.A total of 248 pregnant women(case group=124,control group=124)were included from June 2015 to July 2019 in Nanning city.The concentrations of 8 trace elements and 31 bile acids in serum were measured in early pregnancy.Conditional logistic regression and BKMR models were used to analyze the associa-tion and combined effect between trace elements and GDM risk,respectively.Orthogonal partial least squares-discriminant anal-ysis(OPLS-DA)was used to screen potential bile acid biomarkers associated with GDM,and then conditional logistic regression was used to determine the association between specific bile acid levels and GDM risk.Multiple linear regression was used to e-valuate the association of serum trace element concentrations with differential bile acid metabolites.Mediation analysis was used to evaluate the mediating role of bile acids in the relationship between trace element exposure and GDM.Results After adjus-ting for confounding factors,serum vanadium(V)was found to be positively associated with the risk of GDM,while chromium(Cr),manganese(Mn),zinc(Zn),selenium(Se)and molybdenum(Mo)were negatively correlated with the risk of GDM(all P＜0.05).The OPLS-DA model and conditional Logistic regression analysis showed that taurocholic acid(TCA),glycochenodeoxy-cholic acid 3-sulfate(GCDCA-3S),glycochenodeoxycholic acid-3-O-β-glucuronide(GCDCA-3Gln),glycoursodeoxycholic acid-3-sulfate(GUDCA-3S),taurodeoxycholic acid-3-sulfate(TDCA-3S),and chenodeoxycholic acid(CDCA)might be potential bile acid metabolic markers of GDM(all P＜0.05).The concentrations of multiple trace elements were also significantly correlated with the levels of specific bile acids(all P＜0.05).Mediation analysis showed that GCDCA-3Gln and TCA mediated the associa-tion between serum Zn and Se and GDM risk,respectively(all P＜0.05).Conclusion Serum trace elements such as V and Cr are significantly associated with the risk of GDM in early pregnancy,and changes in bile acid metabolism may precede the occur-rence of GDM.It is suggested that the effect of trace elements on the metabolism of bile acids,especially conjugated bile acids,may be one of the mechanisms affecting the risk of GDM.
RESUMO
A 2-(2'-hydroxyphenyl)benzimidazole (HBI)-based ratiometric fluorescent probe, known as BTEP, was synthesized using 5-bromosalicylaldehyde as the raw material via Sonogashira coupling and condensation reaction. This probe was designed for rapid detection of boron trifluoride solutions and gases. The N and O coordination atoms in the probe undergo a boron difluoride addition with BF3, which affects the process of excited state intramolecular proton transfer (ESIPT) leading to a blue shift of fluorescence emission. Obvious changes in the fluorescence signal can be observed within 60 seconds. The introduction of an acetylene trimethylsilane fragment increases the conjugate plane and is beneficial to improving the selectivity of the probe. The I408/I479 fluorescence ratio of the probe displays a linear relationship with the concentration of BF3 in the range of 5-50 µM, with a detection of limit as low as 69.5 nM. Furthermore, the probe demonstrates specific and selective recognition of BF3 among eight common interference substances. Test strips prepared using BTEP have the capability of real-time naked-eye detection of trace BF3 gas.