ABSTRACT
OBJECTIVE: To explore the similarity of the dissolution curves of self-made and original telmisartan /hydrochlorothiazide tablets and provide basis for the prescription and process screening of self-made preparation and the quality similarity evaluation with original preparation. METHODS: The dissolution curves of telmisartan and hydrochlorothiazide from self-made and original preparations in four different dissolution media were determined using HPLC. The HPLC method was performed on Welch Ultimate XB-C8 column (4.6 mm × 250 mm, 5 μm) with mobile phase A consisting of ammonium dihydrogen phosphate solution (2.0 g ammonium dihydrogen phosphate was dissolved in 1 L water then adjusted to pH 3.0 with phosphoric acid) and mobile phase B consisting of acetonitrile- methanol (50:50) at a flow rate of 1.2 mL•min-1. The detection wavelength was set at 270 nm. The injection volume was 20 μL. Then f2 factor method was used to evaluate the similarity. RESULTS: The dissolution curves of self-made and original preparations of telmisartan /hydrochlorothiazide tablets in different dissolution media showed similarity, with the f2 factor ≥50 or the dissolution rate within 15 min≥85%. CONCLUSION: The dissolution behaviors of self-made and original telmisartan /hydrochlorothiazide tablets are basically similar, which indicates that the prescription and technology of self-made preparation are reasonable and feasible.
ABSTRACT
<p><b>OBJECTIVE</b>To analyze the immunological characteristics of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model and examine the therapeutic effects and mechanisms of Astragalus polysaccharides (APS) treatment.</p><p><b>METHODS</b>Thirty-two male specific pathogen free Spragne-Dawley rats were randomly equally assigned to four groups: control, TNBS, APS and prednisone groups. Experimental colitis was induced by enema administration of TNBS. Then rats were treated with APS (0.5 g•kg•day, once daily) or prednisone (1.0 mg•kg•day, once daily) by gavage for 14 days. Macroscopic lesion and histological damage were determined, and activity of myeloperoxidase (MPO) was measured in the colonic tissues. Expressions of T-box expressed in T-cells (T-bet) and GATA-binding protein-3 (GATA-3) were determined by immunohistochemistry analysis and western blot.</p><p><b>RESULTS</b>Both macroscopic lesion and histological colonic damage induced by TNBS were reduced by APS and prednisone treatment. These were accompanied by significant attenuation of MPO activity (P=0.03). TNBS intervention enhanced the expression of both GATA-3 and T-bet, but the expression of T-bet was significantly enhanced than that of GATA-3, resulting in significant reduction of GATA-3/T-bet ratio (P=0.025). APS administration enhanced the expression of T-bet (P=0.04) and GATA-3 (P=0.019) in comparison to TNBS group, and resulting in an up-regulated GATA-3/T-bet ratio. Prednisone treatment inhibited both expressions; however it also resulted in up-regulation of the GATA-3/T-bet ratio.</p><p><b>CONCLUSIONS</b>These results demonstrated that APS exerted a beneficial immune regulatory effect on experimental colitis. It promoted the expression of T helper cell 1 (Th1) and T helper cell 2 (Th2) specific transcription factors but ultimately favor a shift toward Th2 phenotype, suggesting that APS possessed therapeutic potential in experimental colitis.</p>