Conclusions
CS indeed represent an interesting group of compounds in the combat against multidrug-resistant cancers. After examining the cytotoxic effect of a chemical library of 66 CS on drug-sensitive and multidrug-resistant leukemia cells, implementation of QSAR and molecular docking analyses indicated a differential expression of Na+/K+-ATPase, which considerably contributes to the mode of action of these compounds. We have observed a down-regulation of Na+/K+-ATPase in multidrug-Conclusions
The aim of this work was to developed the standardized protocol of human urine pretreatment for the determination of steroids by GC/C/IRMS. The lack of the standardized protocol for the extensive process of human urine pretreatment could results in the discrepancy of the IRMS results thus influence the final decision related to the individual sportsman. Having in mind The validity of the proposed protocol was demonstrate with two examples urine, selected after positive finding based on the GC/MS results. The developed procedure was used to discriminate endogenous versus exogenous anabolic–androgenic steroids in athletes urine by GC/C/IRMS. The entire analytical protocol was successfully used for the confirmation of positive founding urine by evaluation T/E ratio or endogenous steroids.