ABSTRACT
Objective To investigate the effects of different concentrations of crocin on receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastogenesis using the monocyte-macrophage cell line RAW264.7. Methods The monocyte-macrophage cell line RAW264.7 was cultured routinely.After treatment with 0,6.25,12.5,25, 50,100,200 and 400 μmol/L crocin,cell counting kit-8(CCK-8)assay was used to analyze the viability of RAW264.7 cells to screen out the appropriate experimental concentration. RAW264.7 cells were induced by RANKL (100 ng/L) to form osteoclasts. After treated with 0, 12.5, 50 and 100 μmol/L crocin respectively, the number of osteolasts was counted by tatrate resistant acid phosphatasec (TRAP) staining. Real-time PCR was used to detect the mRNA expression levels of calcitonin receptor(CTR),nuclear factor of active T cells 1(NFATC1),C-fos and TRAP.Results No significant effects of crocin (within 0-100 μmol/L) were found on the viability of RAW264.7 cells (P>0.05). However, When crocin concentration was over 100 μmol/L,the cell proliferation was decreased,and which showed a significant inhibitory effect on proliferation (P<0.05). Thus, 0-100 μmol/L crocin was selected as the experiment concentration. The amount of differentiated osteolasts and the expression levels of CTR,NFATC1,C-fos and TRAP mRNA were decreased significantly with the increased concentrations of crocin(P<0.05).Conclusion At a certain concentration(0-100 μmol/L),the higher levels of crocin could inhibit RANKL-induced osteoclastogenesis.
ABSTRACT
Objective To investigate the clinical distribution and antimicrobial resistance of carbapenem-resistant Enterobacteriaceae (CRE) in Dongguan.Methods CRE isolated from hospitalized patients in 22 secondary and above medical institutions which participated in bacterial monitoring in Dongguan between January 2015 and June 2016 were retrospectively analyzed,antimicrobial resistance was analyzed by WHONET 5.6 software.Results A total of 71 CRE isolates were detected,with a isolation rate of 0.34％ (71/20 713).53 strains(74.65％) of CRE were isolated from patients aged 15-60 years old;46 (64.79 ％) were from male patients;CRE were mainly isolated from patients in intensive care unit(36 strains,50.70 ％);the main specimen was sputum(34 strains,47.89 ％),followed by urine (11 strians,15.49 ％) and wound secretion(6 strains,8.45 ％);the main infection type was healthcare associated infection (64 strains,90.14 ％);CRE were mainly distributed in tertiary hospitals(56 strains,78.87 ％),the isolation rate of CRE in tertiary and secondary hospitals were 0.41 ％(56/13 677)and 0.21％(15/7 036) respectively.71 strains of CRE were all resistant to imipenem,resistance rate to meropenem was 81.12％,only amikacin and tobramycin had drug resistance rates of ＜40％ (21.38％ and 38.79％ respectively),resistance rate to trime thoprim/sulfamethoxazole was 48.23 ％,while resistance rates to fluoroquinolones,third-generation cephalosporins,and enzyme inhibitors were all＞60.Conclusion The isolation rate of CRE in Dongguan is lower than that of the whole nation and the other provinces,effective prevention and control measures should be taken according to the key population and departments that isolated CRE,antimicrobial use should be rational.