RÉSUMÉ
Objective:To study whether Tanreqing injection （TRQ） can alleviate the body injury in the process of infection by inhibiting the production and release of <italic>α</italic>-hemolysin of <italic>Staphylococcus aureus</italic> under sub-minimal inhibitory concentration， and to provide experimental basis for better guidance of clinical medication. Method:The effects of TRQ on the minimum inhibitory concentration （MIC） and bacterial growth of <italic>S.aureus</italic> were determined firstly by microplate method and time-growth curve. The different sub-minimal inhibitory concentrations of TRQ were co-cultured with bacteria or bacterial supernatants， and then co-incubated with defibrillated rabbit blood to detect the inhibitory and neutralizing effects of TRQ on <italic>S.aureus</italic> <italic>α</italic>-hemolysin. Cell counting kit-8 （CCK-8） cell viability assay was used to detect the protective effect of TRQ on <italic>S. aureus</italic>-mediated damage to human alveolar epithelial cells （A549）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the effect of sub-minimal inhibitory concentration of TRQ on the mRNA expression of <italic>S.aureus</italic> <italic>α</italic>-hemolysin regulatory genes hla and agrA. Result:The MIC of TRQ to <italic>S.aureus </italic>was 1/8 of the stock solution， and the sub-minimal inhibitory concentration （1/64MIC-1/16MIC） TRQ used in this study did not affect the growth of bacteria. 1/64MIC-1/16 MIC TRQ had the effect of inhibiting and neutralizing the hemolytic activity of <italic>α</italic>-hemolysin， with a protective effect on <italic>S.aureus</italic> supernatant-mediated A549 cell damage， and its inhibitory effect on <italic>α</italic>-hemolysin was closely related to the inhibition of hla and agrA mRNA expression. Conclusion:The sub-minimal inhibitory concentration TRQ can inhibit and neutralize the hemolytic activity of <italic>α</italic>-hemolysin of <italic>S.aureus</italic>， with a protective effect on A549 cell damage mediated by <italic>S.aureus</italic> infection， and its mechanism of inhibiting <italic>α</italic>-hemolysin is closely related to the interference with agr regulatory system.
RÉSUMÉ
Objective::To explore the feasibility of the rapid identification system(MALDI-Biotyper System) of microorganisms for rapid identification of Pseudomonas aeruginosa and clinical isolation of Staphylococcus aureus. Method::Identification quality control and clinical isolation were conducted for drug resistance of S. aureus by microbial rapid identification system and broth dilution method. The scores of microbial rapid identification system were compared with the MIC value of broth dilution method. The drug resistance of P. aeruginosa was simultaneously identified to determine the accuracy and applicability of the rapid identification system of microorganisms. Result::The scores of the microbial rapid identification system showed that the score of sensitive quality control strain S. aureus was higher than 2.000, and the that of resistant strain of methicillin-resistant S. aureus(methicillin-resistant S. aureus, MRSA)was between 1.700 and 2.000.The score of clinically isolated S. aureus was between 1.700 and 2.000, which suggested the drug resistance and was consistent with the MIC value of the broth dilution method. At the same time, the systemic identification value of the P. aeruginosa, which is independent of the quality control sensitive strain, was greater than 2.000, showing sensitivity and it was a sensitive strain itself, which was consistent with the results. Conclusion::The microbial rapid identification system scoring method can be used for the rapid identification of the drug resistance of S. aureus and P. aeruginosa.