RESUMEN
The association of meloxicam and pridinol is indicated for treating muscular contractures and low back pain. A dissolution test for the meloxicam-pridinol combined tablet formulation was developed and validated, using a suitable HPLC method for simultaneously quantitating both dissolved drugs. The optimized conditions include the use of USP apparatus 2 at a paddle rotation rate of 75 rpm and 900 ml of 50 mM phosphate buffer (pH= 7.5) as dissolution medium, at 37.0±0.5°. The test, which demonstrated to be robust against small changes in bath temperature, paddle rotation speed and pH of the dissolution medium, was applied to two different brands of tablets; the corresponding dissolution profiles were constructed and both brands showed to dissolve at least 75% of the drugs at the 45 min time point.
RESUMEN
The synthesis and antimicrobial activity of isochromane-type analogs of the pyranonaphthoquinone antibiotics are reported. Isochromane derivatives with (17a, b) and without (22a, b) a C-4 hydroxyl moiety and their corresponding quinones (19a and 23), were prepared. Both quinones exhibited antimicrobial activity against Staphylococcus aureus, Bacillus atrophaeus and Streptococcus agalactiae, while the related isochromanes were inactive. The results suggest that the quinone moiety is important for biological activity while the C-4 hydroxyl may not be essential.
Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Benzoquinonas/síntesis química , Benzoquinonas/farmacología , Cromanos/síntesis química , Antibacterianos/química , Benzoquinonas/química , Cromanos/química , Cromanos/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Espectrofotometría InfrarrojaRESUMEN
A numerical method, based on the use of spectrophotometric data coupled to PLS-1 multivariate calibration, is reported for the simultaneous determination of furosemide and amiloride hydrochloride in synthetic samples and commercial tablets. The method was applied in the concentration ranges of 8.0-13.0 mg l(-1) for furosemide and 1.0-1.6 mg l(-1) for amiloride hydrochloride. Its accuracy and precision were determined, and it was validated by the analysis of synthetic mixtures of both drugs. The method was successfully applied to the quantitation of furosemide and amiloride hydrochloride in three different pharmaceutical formulations, providing results in agreement with those obtained by HPLC. It allowed the rapid, accurate and precise simultaneous estimation of the concentration of both analytes of interest in spite of their important spectral overlap, high concentration relationship and the presence of small amounts of different, unmodelled, absorbing excipients.
Asunto(s)
Amilorida/análisis , Furosemida/análisis , Amilorida/administración & dosificación , Calibración , Cromatografía Líquida de Alta Presión , Furosemida/administración & dosificación , EspectrofotometríaRESUMEN
A flap needs close contact with its bed for optimal flap survival. Using a rat dorsal flap model, flap/bed contact times were varied by use of a sterile polyethylene film. In addition, the flap was modified either by removing the panniculus carnosus or by converting the distal flap into a skin graft. Finally, the effect of using a dressing was assessed. Several observations were made: (1) The initial 6 to 12 hours of a flap's interaction with its bed is critical for optimal survival; (2) fluorescein accurately predicted flap survival upon polyethylene removal; (3) removing the panniculus carnosus increased flap and skin graft survival; (4) dressing allowed flaps and skin grafts to better withstand bed deprivation; and (5) distal flaps and skin grafts under various conditions responded differently to bed deprivation.