Search

Objective: To study the association between phthalate esters (PAEs) metabolites in maternal urine and 11beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2 ) enzyme activity, explore the possible mechanism of PAEs effect on fetal development., Methods: All of 33 cases of intrauterine growth retardation (IUGR) newborn were selected by random sampling in 2012. And 33 cases of normal control newborn were enrolled, use high performance liquid chromatography-tandem mass spectrometry method was used to detect 4 kinds of phthalate esters (PAEs) metabolites in maternal urine: mono-n-butyl phthalate ester (MBP), mono (2-ethylhexyl) phthalate (MEHP), mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) and three kinds of cortisol corticosterone metabolites, tetrahydrocortisol (THF), allo-tetrahydrocortisol (allo-THF), tetrahydrocortisone (THE), and analyze the association between phthalate esters (PAEs) metabolites in maternal urine and 11β-HSD2 enzyme activity., Results: MBP, MEHP, MEHHP, MEOHP metabolites can be detected in 98% (65 cases) , 89% (59 cases), 91% (60 cases), 91% (60 cases) of all 66 maternal urine samples, respectively. The median concentrations of test material in case group were 31.20 ng/ml for MBP, 24.61 ng/ml for MEHHP, 11.72 ng/ml for MEOHP and 48.67 ng/ml for SumDEHP which were significantly higher than those of the control group (were 17.32, 12.03, 5.68 and 28.64 ng/ml); 11β-HSD2 activity in case group ((THF+allo-THF)/THE = (0.79 ± 0.09) ng/ml) was significantly lower than that of the control group((THF+allo-THF)/THE = (0.58 ± 0.04) ng/ml); PAEs metabolites MBP (β' = 1.12), MEHHP(β' = 1.14), MEOHP(β' = 1.10), SumDEHP(β' = 1.08) in baby boy mother's urine was reversely correlated to 11β-HSD2 activity., Conclusions: PAEs could affect fetal development by inhibit 11β-HSD2 activity.

Bare nonporous silica particles with diameter around 1 microm were prepared. A 20 cm section of a total length of 45 cm capillary (100 microm i. d.) was packed electrokinetically and the separation performance of basic compounds was investigated in the pressurized capillary electrochromatography (pCEC) system using 1 microm nonporous bare silica spheres as stationary phase and acetonitrile-water as mobile phase. The effects of the composition of the mobile phase, the concentration of the buffer, pH value, applied voltage and so on on the separation performance were investigated. The experimental results demonstrated that the bare silica column showed a typical reversed phase separation mechanism when it was used for separation of basic compounds. The separation performance changed slightly with changing buffer concentration. Since the degree of dissociation of the basic compounds depended greatly on the pH value, the interaction between the compounds and stationary phase changed with the changing of pH value, thereby changing the resolution of the compounds. The separation performance increased with the increase of applied voltage. A column efficiency of 35 000 for o-toluidine was obtained when a voltage of 1 kV was applied.