ABSTRACT
The enantiomers separation of thirteen drugs collected in Ch.P2010 was performed on chiral stationary phase of cellulose ramification (chiralpak OD and chiralpak OJ) by high performance liquid chromatographic (HPLC) methods,which included ibuprofen (Cl),ketoprofen (C2),nitrendipine (C3),nimodipine (C4),felodipine (C5),omeprazole (C6),praziquantel (C7),propranolol hydrochloride (C8),atenolol (C9),sulpiride (C10),clenbuterol hydrochloride (C11),verapamil hydrochloride (C12),and chlorphenamine maleate (C13).The mobile phase consisted of isopropanol and n-hexane.The detection wavelength was set at 254 nm and the flow rate was 0.7 mL/min.The enantiomers separation of these thirteen racemates on chiralpak OD column and chiralpak OJ column was studied,while the effects of proportion of organic additives,alcohol displacer and temperature on the separation were studied.And the mechanism of some of racemates was discussed.The results indicated that thirteen chiral drugs could be separated on chiral stationary phase of cellulose ramification in normal phase chromatographic system.The chromatographic retention and resolution of enantiomers could be adjusted by factors including column temperature and the concentration of alcohol displacer and organic alkaline modifier in mobile phase.It was shown that the resolution was improved with reducing concentration of alcohol displacer.When concentration of organic alkaline modifier was 0.2％ (v/v),the resolution and the peak shape were fairly good.Most racemates mentioned above had better resolution at column temperature of 25 ℃.When racemates were separated,the temperature should be kept so as to obtain stable separation results.
ABSTRACT
With the emergence of drug resistant tuberculosis, it is very urgent to find novel anti-tuberculosis drugs, especially novel anti-drug-resistant tuberculosis drugs. Because of the slow growth and the need to work in a biosafty environment of Mycobacterium tuberculosis, the development of evaluation of drug effect is severely impeded. In order to solve these issues, non-pathogenic fast-growing Mycobacterium smegmatis is introduced as test organism. The inhA is one of a target of isoniazid (INH) overexpression or mutation of this gene in Mycobacterium tuberculosis conferring resistant to INH. A recombinant plasmid bearing inhA was constructed and electroporated into Mycobacterium smegmatis, using shuttle expression vector pMV261. Transformants were induced to express a protein of inhA, identified by SDS-PAGE. Results show that Mycobacterium smegmatis containing inhA plasmids exhibited 100-fold or greater increased resistance to INH, but it conferred no increased resistance to others first-line anti-tuberculosis drugs. Resazurin microtiter assay plate testing of Mycobacterium smegmatis susceptibility to drugs is a rapid, simple, and inexpensive method and could decrease color background of drugs by detecting fluorescence. It will be benefit for high-throughout screening of drugs of anti-isoniazid-resistant Mycobacteria.
ABSTRACT
Strict regulation of HIV-1 PR function is critical for efficient production of mature viral particles. During viral protein expression and viral assembly, HIV-1 PR located within Gag-Pol precursor must be inactive to prevent premature cytoplasmic processing of the viral Gag and Gag-Pol precursors. Premature activation of HIV-1 precursors leads to major defects in viral assembly and production of viral particles. A cell-level premature activation of HIV-1 precursors assay using bioluminescence resonance energy transfer (BRET) was established. Three thousand compounds were screened to evaluate this assay. The results showed that the assay is sensitive, specific and stable (Z' factor is 0.905).