ObjectiveTo investigate antifungal activity in vitro of single or combination of triazole and echinocandin against Aspergillus species. MethodsBased on EUCAST protocol,the susceptibilities of 62 isolates of Aspergillus spp. were determined for voriconazole (VRC),itraconazole (ICZ),caspofungin (CAS) and micafungin (MICA). For VRC and ICZ,MIC-0 and MIC-2 were determined. For CAS and MICA,minimum effective concentration (MEC) and MIC-2 were determined. The fractional inhibitory concentration (FIC) was used to evaluate the effect of combination of triazole and echinocandin. ResultsIndifference was found in 2 isolates of Aspergillus fumigatus in combination of ICZ and CAS or MICA by using MIC-0 endpoint. Synergy was found in all other isolates of Aspergillus spp.With MIC-2 and MEC endpoints,synergy for VRC and CAS,VRC and MICA,ICZ and CAS and ICZ and MICA was found in 16,21,11 and 14 isolates of Aspergillus fumigatus,9,13,9 and 11 isolates of Aspergillus flavus,0,2,1 and 1 isolates of Aspergillus niger,respectively. ConclusionThe in vitro sensitivity results of combination of triazole and echinocandin are different with different endpoints. Thus,the efficacy of combination of triazole and echinocandin can not predicted by in vitro sensitivity and should be further confirmed in invasive aspergillosis animal experiments.
This study is to investigate the inhibitory effect of different concentrations of zoledronic acid on the activity of osteoclasts, to obtain characteristics on inhibitory effect and to find the lowest effective concentration of zoledronic acid. Marrow cells of C57 mice (6 weeks) were cultured in vitro. Osteoclasts were induced by single nuclear cells. According to the concentration of zoledronic acid, we set up the experimental group with five different concentrations, i.e. 1×10–8 mol/L, 1×10–7 mol/L, 1×10–6 mol/L, 1×10–5 mol/L, and 1×10–4 mol/L. The control group did not contain any bisphosphonate. By tartrate resistant acid phosphatase staining, the number of multinuclear cells, cells through the filter and bone resorption lacune were counted. Five days after the cultivation, the number of multinuclear cells in the experimental group decreased with the increase of concentration of zoledronic acid. Inhibition on the formation of osteoclasts in vitro was effective at 1×10–6 mol/L. At the concentration of 1×10–5 mol/L, the effect of inhibition on migration of osteoclast and bone resorption was more obvious. The effect was further enhanced at concentration of 1×10–4 mol/L. However, the concentration and inhibition curves were gradually mild. The inhibitory effect on different concentrations of zoledronic acid on the activity of osteoclasts was different. The inhibition effect was obvious at 1×10–6 mol/L. We should pay attention to administrate appropriate concentration of zoledronic acid in the clinical applications.