AIM:To study the pharmacokinetics and relative bioavailability of citalopra hydrobromide in human plasma.METHODS:The citalopra hydrobromide concentrations in plasma were determined by HPLC-UV.The column was Lichrospher ODS(5 ?m,250 mm?4.6 mm).The mobile phase was acetonitrile-0.1 mol/L KH2PO4 buffer-triethylamine(35:65:0.3,v/v/v).The flow rate was 1 mL/min.The detection wavelength was 240 nm.The test and reference formulations of citalopra were given to 18 healthy male volunteers.RESULTS:The calibration curve was linear within the range of 2-128 ?g/L,r=0.9992.The minimum detection limit was 1 ?g/L.The recovery was 80%-88%,the RSDs of inter-day and intra-day were not more than 15%.After a single oral dose of 20 mg citalopra hydrobromide was given,the main pharmacokinetic parameters tmax were(4.6?1.0),(4.4?1.4) and(4.0?1.4) h;Cmax were(70?19),(71?17) and(66?21) ?g/L;and t1/2 were(37?9),(37?6) and(36?6) h respectively.CONCLUSION:No significant difference exists among the pharmacokinetic parameters of the three formulations.They are bioequivalent.

Objective To investigate the role of dendritic cell (DC) subsets and T cell subpopulations expressing different intracellular cytokines in the pathogenesis of syphilis. Methods Flow cytometry was utilized to measure the frequencies of peripheral DC subsets and IFN-γ-, IL-2-, IL-4-, IL-10-expressing peripheral CD4+ and CD8+ T cell subpopulations in 20 patients with syphilis before and after therapy, and in 15 healthy human controls. Results The frequency of CD11c+ DC was significantly lower in pretreated patients than that in treated patients (P<0.01), but higher than that in the normal controls (P<0.05), and the same was true for the frequency of IFN-γ-expressing T cells, IL-2-expressing T cells, and IL-12-expressing T cells. By contrast, a decrease was noticed in the frequency of IL-4-expressing T cells and IL-10-expressing T cells in pretreated patients compared with that in the normal controls. Furthermore, in patients with syphilis, the frequency of CD11c+ and CD123+ DC was unrelated to the percentage of IFN-γ-expressing and IL-12- expressing T cells (both P>0.05). Conclusions IFN-γ, IL-2 and IL-12 may exert an immunoregnlatory effect in the eliminating of Treponema pallidum, whereas IL-4 and IL-10 may perform an imrnunoinhibitory effect.