Expression and function of transcription factor RUNX2 in synovial tissues of rheumatoid arthritis

Objective:This study aimed to explore the expression profile of transcription factor Runt-related transcription factor 2(RUNX2)in the synovial tissues of rheumatoid arthritis(RA)and its effect on the apoptosis of RA fibroblast-like synovial cells(RA-FLS),and to screen new targets for the diagnosis,treatment and prognosis of RA.Methods:The expression and localization of mRNA and protein of RUNX2 in the synovial tissues were detected by real-time quantitative PCR(q PCR)and immunohistochemical staining,respectively.The effect of the expression of exogenous RUNX2 on the apoptosis process of RA-FLS cell line MH7A was investigated by flow cytometry,and the activation of NF-κB signaling pathway was detected by western blotting.Results:The expression of RUNX2 mRNA was significantly higher in the synovial tissues from RA patients,compared to that in the OA patients(P<0.05).RUNX2 protein was mainly localized in the nuclear of the RA synovial cells.Overexpression of exogenous RUNX2 could notably decrease the apoptosis of RA-FLS,which was substantially reversed by pretreatment with SN50,a specific inhibitor of NF-κB pathway.Compared with blank group and negative control group(p CMV6-AC-GFP-vector),the apoptotic rate of exogenous RUNX2 overexpressing(pCMV6-AC-GFP-RUNX2)MH7A cells was significantly decreased(P<0.05).NF-κB signaling pathway activity was significantly increased(P<0.05),and this effect could be effectively reversed by NF-κB signal pathway-specific inhibitor SN5.Conclusion:The high expression of UNX2 in RA synoviocytes could significantly inhibit the spontaneous apoptosis of cells,and it was related to the abnormal activation of NF-κB signaling pathway.In-depth studies of RUNX2/NF-κB signaling pathways will help to identify novel therapeutic targets for RA.

Emission factors, ozone and secondary organic aerosol formation potential of volatile organic compounds emitted from industrial biomass boilers

To evaluate the potential benefits of biomass use for air pollution control, this paper identified and quantified the emissions of major reactive organic compounds anticipated from biomass-fired industrial boilers. Wood pellets(WP) and straw pellets(SP) were burned to determine the volatile organic compound emission profiles for each biomass-boiler combination. More than 100 types of volatile organic compounds(VOCs) were measured from the two biomass boilers. The measured VOC species included alkanes, alkenes and acetylenes, aromatics, halocarbons and carbonyls. A single coal-fired boiler(CB) was also studied to provide a basis for comparison. Biomass boiler 1(BB1) emitted relatively high proportions of alkanes(28.9%–38.1% by mass) and alkenes and acetylenes(23.4%–40.8%),while biomass boiler 2(BB2) emitted relatively high proportions of aromatics(27.9%–29.2%)and oxygenated VOCs(33.0%–44.8%). The total VOC(TVOC) emission factors from BB1(128.59–146.16 mg/kg) were higher than those from BB2(41.26–85.29 mg/kg). The total ozone formation potential(OFP) ranged from 6.26 to 81.75 mg/m^3 with an average of 33.66 mg/m^3 for the two biomass boilers. The total secondary organic aerosol potential(SOAP) ranged from 61.56 to 211.67 mg/m^3 with an average of 142.27 mg/m^3 for the two biomass boilers.The emission factors(EFs) of TVOCs from biomass boilers in this study were similar to those for industrial coal-fired boilers with the same thermal power. These data can supplement existing VOC emission factors for biomass combustion and thus enrich the VOC emission inventory.