Simultaneous quantification of chlorogenic acid and taurocholic acid in human plasma by LC-MS/MS and its application to a pharmacokinetic study after oral administration of Shuanghua Baihe tablets / 中国天然药物

An LC-MS/MS method was developed and validated for the simultaneous quantification of chlorogenic acid (CGA) and taurocholic acid (TCA) in human plasma using hydrochlorothiazide as the internal standard. The chromatographic separation was achieved on a Hedera ODS-2 column with a gradient elution using 10 mmol·L(-1) of ammonium acetate buffer solution containing 0.5% of formic acid - acetonitrile as mobile phase at a flow rate of 300 μL·min(-1). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring in negative ESI mode. The method was fully validated over the concentration ranges of 0.1-10 ng·mL(-1) for CGA and 2-150 ng·mL(-1) for TCA. It was successfully applied to a pharmacokinetic study of CGA and TCA in healthy Chinese volunteers after oral administration of Shuanghua Baihe tablets (SBTs). In the single-dose study, the maximum plasma concentration (Cmax), time to reach Cmax (Tmax) and elimination half-life (t1/2) of CGA were (0.763 8 ± 0.542 0) ng·mL(-1), (1.0 ± 0.5) h, and (1.3 ± 0.6) h, respectively. In the multiple-dose study, the Cmax, Tmax and t1/2 of CGA were (0.663 7 ± 0.583 3) ng·mL(-1), (1.1 ± 0.5) h, and (1.4 ± 0.7) h, respectively. For TCA, no significant characteristic increasing plasma TCA concentration-time curve was found in the volunteers after oral administration of SBTs, indicating its complicated process in vivo as an endogenous ingredient.

Expression of nuclear factor-kB and COX-2 and their role in experimental allergic encephalomyelitis in rabbits / 中华神经医学杂志

Objective To study the expression of nuclear factor-kB (NF-KB) and COX-2 and their relationship in experimental allergic encephalomyelitis (EAE), and investigate their role in the pathogenesis of EAE. Methods All rabbits were classified three groups in according to making models by different immunogens: group A is immuned without immunogen, group B is immuned with R-SCH, group C is immunod with C-SCH. Immunofluorescence and immunohistochemistry were performed for morphological observations of the brain tissues in all animals, and then the activity of NF-KBp65 was detected using enzyme-linked immunosorbent assay. Results The expressions of NF-KBp65 and COX-2 were observed in brain issues with EAE. Significant differences were found in the number of cells positive for NF-KBp65 and COX-2 between EAE groups and the control group. NF-KBp65 and COX-2 expressions were associated with the symptoms of EAE. In addition, significantly increased activity ofNF-kBp65 was noted in EAE, which is immuned with R-SCH. Conclusion NF-KB and COX-2 are expressed in rabbits with EAE and play important roles in the pathogenesis of EAE.

Quantitative determination and pharmacokinetics of retinamido-ester in rat plasma by liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry / 药学学报

A highly sensitive, rapid and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantitative determination of retinamido-ester in rat plasma was developed and validated. A simplified protein precipitation with acetonitrile was employed for the sample preparation. The separation was carried out on an Agilent TC C18 column (150 mm x 4.6 mm ID, 5 microm particle size) with the mobile phase consisted of methanol-water-formic acid (93: 7: 0.1). Simvastatin was used as internal standard. The detection was performed on a trap-quadrupole tandem mass spectrometer by selected reaction monitoring (SRM) scan mode via atmospheric pressure chemical ionization (APCI). The range of calibration curve was 0.05-50 ng x mL(-1) and the limit of quantification was 10 pg x mL(-1). The intra- and inter-day precision values were between 95.97% and 104.43%, and RSD was between 4.63% and 10.69%, respectively. This method was applied to determine the pharmacokinetic parameters. The main pharmacokinetic parameters of retinamido-ester after oral administration via gastric gavage of 2.5, 5, 10 mg x kg(-1) were as follows, T(1/2): (11.28 +/- 7.23), (8.90 +/- 3.82), (8.01 +/- 5.65) h; AUC(0-infinity): (103.41 +/- 61.46), (190.23 +/- 74.99), (421.66 +/- 229.20) ng x h x mL(-1); MRT: (6.31 +/- 0.75), (5.98 +/- 0.71), (6.18 +/- 0.97) h; CL/F: (30.10 +/- 13.67), (29.58 +/- 10.59), (31.18 +/- 17.51) L x h(-1) x kg(-1); Vd/F: (414.94 +/- 159.82), (356.16 +/- 139.85), (369.28 +/- 322.72) L x kg(-1), respectively.

Itraconazole in the treatment of superficial candidal infections: twelve years' clinical experience / 中国医学科学院学报

Itraconazole has been used to treat superficial candidal infections in China for 12 years with promising efficacy and safety. This article retrospectively reviewed literatures published in the mainstream journals in China with an attempt to find a reasonable therapy for Chinese populations.