Preparation and determination of desethylamiodarone in dog lung by HPLC-MS.

A novel method was developed for the preparation and determination of desethylamiodarone in dog lung by high-performance liquid chromatography (HPLC) with amiodarone as a standard. The selected dog was orally given amiodarone, then executed and the active metabolite desethylamiodirone in lung tissue was isolated, concentrated and purified by Waters C18 column (25 mm x 250 mm, 10 microm) with mobile phase of acetonitrile-100 mmol/L acetic acid containing 15 mmol/L diethylamine (55:45 v/v) at a flow rate of 10.0 mL/min. Hypersil ODS2 column (4.6 mm x 250 mm 5 microm) was used to analyze amiodarone and desethylamiodarone, with the same mobile phase at a flow rate of 1.0 mL/min, the detection wavelength was 237.5 nm. Atmosperic pressure electronic spray ionization (AP-ESI) and ion mass spectral (m/z) of 618.1(M + H) were selected to validate desethylamiodarone. The f(i) of desethylamiodarone and amiodarone were 1.04 +/- 0.02 and 1.020 +/- 0.01, respectively. It indicated that desethylamiodarone can be separated and purified by preparational HPLC after Mass Spectrometry (MS) validation and quantified according to f(i) of amiodarone indirectly. The proposed method enables the preparation and determination of desethylamiodarone in dog lung successfully.

[Synergistic cytotoxic effect of immunotoxin HEL-PE38KDEL and cis-platin against tumor cells].

BACKGROUND AND OBJECTIVE: The immunotoxin of HEL-PE38KDEL has been proven to be a novel biological reagent which has specific cytotoxic effect against breast cancer cells with positive erbB-2, 3, 4. However it has not been tested the interaction of the immunotoxin and the conventional chemical anti-cancer drugs. This study was designed to investigate the mechanism of the synergistic effect between HEL beta 1-PE38KDEL and cisplatin. METHODS: The tests of Annexin V binding and Western blot were performed to detect the apoptosis in the breast cancer cell lines MDA-MB-453, 2LMP, and the gastric cancer cell of N87 treated with single or drug combination. RESULTS: In MDA-MB-453 and N87 with high expression of erbB-2, 3, 4, percentage of the apoptosis cell was significantly higher in the group treated with the drug combination than that in the group treated with the single drug (P < 0.01). To the contrast, in 2LMP cells with low expression of erbB-2, 3, 4, there was no difference between the drug combination and the single drug group (P > 0.05). In MDA-MB-453 and N87, degradation of PARP, caspase-3 was more in the group treated with the drug combination than that in the group treated with the drug alone. Overexpressions of bcl-2, mp53 were inhibited in the group treated by the drug combination. On the contrary overexpressions of bcl-2, mp53 were not inhibited in the group treated with the single drug. While these changes of PARP[poly (ADP)-ribose polymerase], caspase-3, mp53, bcl-2 could not be observed in the control cell line of 2LMP. CONCLUSIONS: The combination of HEL beta 1-PE38KDEL and cis-platin could promote the synergistic effect on apoptosis in the target cancer cells with high expression of erbB-2, 3, 4 which might be one of the mechanism of these two drugs.