ABSTRACT
OBJECTIVE: To design a rapid test to detect the rifampin (RIF) and isoniazid (INH) resistant mutant based on polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique that analyzes the katG, rpoB genes. METHODS: Biochemical test as well as IS6110 targeting PCR revealed 103 clinical samples were tuberculosis. To determine the susceptibility of isolates to anti TB drugs, the proportional method was used. Mutations presented within the amplified products of the katG, rpoB genes were evaluated by SSCP. RESULTS: Using proportional method, 12 (11.6%) and 9 (8.7%) isolates were resistant respectively to INH and RIF and 9 (8.7%) isolates showed resistance to both drug (multi-drug resistant tuberculosis). Three (2.9%) multi-drug resistant tuberculosis and two INH resistant isolates were detected by the PCR-SSCP and sequencing. The sensitivity and specificity of PCR-SSCP for multi-drug resistant isolates were 33% and 100%, respectively. CONCLUSIONS: Complete agreement between SSCP and sequencing can indicate that resistance-associated mutations have occurred in other genes except our considered genes.
ABSTRACT
PURPOSE: Exosomes (EXOs) are acellular vehicles used for cancer immunotherapy due to their immune-inducing properties. We synthesized a novel structure based on EXOs and staphylococcal enterotoxin B (SEB) and surveyed its cytostatic effect on a pancreatic cell line. METHODS: EXOs were purified from tumor cells and SEB was anchored on it by protein transfer method. To determine the cytotoxic and apoptosis-inducing effect of this structure, treated cells with different concentrations of EXO/SEB were examined by MTT assay and Hoechst staining method. In addition, the expression rate of bcl-2, bax, bak, fas, bcl-xl and the activity of caspase-3 and caspase-9 were assessed. RESULTS: We observed that 0.5 and 2.5 µg/100µl of EXO/ SEB significantly (p<0.001) stimulated apoptosis after 24 hrs. The concentrations of 0.5 and 2.5µg/100µl of EXO/SEB raised the expression rate of bax, bak, fas (p<0.001) but had no impact on bcl-2 and bcl-xl after 48 hrs. Furthermore, it was shown that 0.5, 2.5 and 5 µg/100µl of EXO/SEB only increased the activity of caspase-3 after 48 hrs (p<0.001). CONCLUSION: Our designed structure, the EXO/SEB, is a novel model being able to induce apoptosis.