RESUMEN
@#New Delhi metallo-β-lactamase-1 (NDM-1) is capable of hydrolyzing nearly all β-lactam antibiotics, posing an emerging threat to public health. There are currently less effective treatment options for treating NDM-1 positive “superbug”, and no promising NDM-1 inhibitors were used in clinical practice. In this study, structure–activity relationship based on thiosemicarbazone derivatives was systematically characterized and their potential activities combined with meropenem (MEM) were evaluated. Compounds 19bg and 19bh exhibited excellent activity against 10 NDM-positive isolate clinical isolates in reversing MEM resistance. Further studies demonstrated compounds 19bg and 19bh were uncompetitive NDM-1 inhibitors with Ki = 0.63 and 0.44 μmol/L, respectively. Molecular docking speculated that compounds 19bg and 19bh were most likely to bind in the allosteric pocket which would affect the catalytic effect of NDM-1 on the substrate meropenem. Toxicity evaluation experiment showed that no hemolysis activities even at concentrations of 1000 mg/mL against red blood cells. In vivo experimental results showed combination of MEM and compound 19bh was markedly effective in treating infections caused by NDM-1 positive strain and prolonging the survival time of sepsis mice. Our finding showed that compound 19bh might be a promising lead in developing new inhibitor to treat NDM-1 producing superbug.
RESUMEN
In order to provide experimental data for the development and application of drug in clinic, we determined the effects of extracts from different parts of folium perillae (L. ) Britt. on hemorheological parameters, extracted from leaves (folium perillae), seeds (fructus perillae) and peduncles (caulis perillae). The results showed that all extracts from different parts of folium perillae (L. ) Britt. can significantly reduce the whole blood viscosity at low shear rate (10 s(-1)), erythrocyte aggregation index, erythrocyte electrophoresis index (P<0.05), and the whole blood reductive viscosity at low shear rate (10 s(-1)) (P<0.01). Extracts from folium perillae and caulis perillae can significantly decrease erythrocyte deformation index (P<0.05), whereas extracts from fructus perillae can not. Extracts from fructus perillae and caulis perillae can significantly decrease plasma viscosity at low shear rate(10 s(-1)), but extracts of folium perillae can not. Aspirin can only decrease the whole blood reductive viscosity at low shear rate and plasma viscosity (P<0.05). All extracts from different parts of folium perillae (L. ) Britt. had no significant effects on hematocrit, erythrocyte rigidity index, fibrinogen concentration , the whole blood viscosity and the whole blood reductive viscosity at middle and high shear rate (60 s(-1),120 s(-1)).