ABSTRACT PreS/S gene mutations could impact virus secretion, infection and immune evasion. However, the relationship between PreS/S mutations and intrauterine transmission has not yet been clarified. Thus, we aimed to explore the associations between PreS/S gene mutations of HBV isolated from mothers and intrauterine transmission. We analyzed the mutations of PreS/S regions of the HBV genome in mothers with HBV DNA levels ≥ 106 IU/mL whose neonates experienced HBV intrauterine transmission (transmission group, GT) and those whose neonates did not experience intrauterine transmission (control group, GC) analyzed using clone-based sequencing. In total, 206 sequences were successfully amplified, including 98 sequences (from 21 mothers) from GT and 108 sequences (from 20 mothers) from GC of genotype C for mutational analysis. Among the 1203 nucleotides of PreS/S regions, there were 219 (18.20%) base substitutions, of which 103 (47.03%) base mutations caused amino acid changes. F80S, A90V and I68T were mutation hotspots. Mothers in GT had a higher mutation rate of A90V in the PreS1 gene than mothers in GC. The A90V mutation increased the risk of HBV intrauterine transmission after adjusting the maternal age and the mode of delivery (OR = 6.23, 95% CI: 1.18–32.97). Moreover, the area under the ROC curve (AUC) for intrauterine transmission due to A90V and a combination of A90V with the mode of delivery were 0.723 (95% CI: 0.575 to 0.891, P = 0.011) and 0.848 (95% CI: 0.723 to 0.972, P < 0.001), respectively. Mothers with the A90V mutation in the PreS1 gene may be a potential risk factor for HBV intrauterine transmission. PreSS PreS S secretion evasion However clarified Thus 10 IUmL IU mL group control clonebased clone based sequencing total amplified 9 2 analysis 120 18.20% 1820 18 (18.20% substitutions 47.03% 4703 47 03 (47.03% changes F80S FS F AV A V IT I T hotspots OR 623 6 23 6.23 95 CI 1.18–32.97. 1183297 1.18–32.97 . 1 32 97 1.18–32.97) Moreover AUC (AUC 0723 0 723 0.72 (95 0575 575 0.57 0891 891 0.891 0.011 0011 011 0848 848 0.84 0972 972 0.972 0.001, 0001 0.001 , 001 0.001) respectively 12 18.20 182 (18.20 47.03 470 4 (47.03 62 6.2 118329 1.18–32.9 3 072 72 0.7 (9 057 57 0.5 089 89 0.89 0.01 01 084 84 0.8 097 0.97 000 0.00 00 18.2 (18.2 47.0 (47.0 6. 11832 1.18–32. 07 7 0. ( 05 5 08 8 0.0 09 0.9 18. (18. 47. (47. 1183 1.18–32 (18 (47 118 1.18–3 (1 (4 11 1.18– 1.18 1.1 1.

The development of a simple and efficient analytical method for determination of enantiomeric purity of 2-(aminomethyl)-1-ethylpyrrolidine was presented. The method was based on pre-column derivatization of 2-(aminomethyl)-1-ethylpyrrolidine with 4-nitrobenzoic acid completing separation of the enantiomers on high performance liquid chromatographic (HPLC) chiral stationary phase (CSP). After optimizing all the effective parameters, the best performances were achieved on a Chiralcel OD-H analytical column (250 × 4.6 mm) using n-hexane: ethanol (98:2, v/v) containing 0.2% triethylamine as mobile phase with a flow rate of 1.0 mL min-1 at 25°C. Online UV and optical rotation (OR) detection was performed at 254 nm. The parameters which have an effect on chiral separation were investigated, including mobile phase additive, organic modifier type and concentration, column temperature and flow rate. The method was tested for precision, accuracy, linearity, limit of detection (LOD), limit of quantification (LOQ) and robustness. The present method is expected to be accurate, stable, rapid and sensitive and can be used for the determination of the enantiomeric purity of 2-(aminomethyl)-1-ethylpyrrolidine in bulk samples.