https://www.selleckchem.com/screening/kinase-inhibitor-library.html Results The amount of soluble protein for periplasmic expression was more when compared with one of the cytoplasmic expressions. The optimum condition for periplasmic expression of GM-CSF was expression at 23°C, using 1 mM IPTG as inducer and in the presence of 0.4 M sucrose. The biological activity of purified GM-CSF on HL-60 cell line was assessed by MTT assay, and the specific activity of produced GM-CSF was determined as 1.2 × 104 IU/μg. Conclusion The present work suggests that periplasmic expression and optimization of cultivation conditions could improve soluble expression of recombinant proteins by E. coli. Copyright © 2019 Advanced Biomedical Research.Background Despite a lot of studies carried out on catastrophic and impoverishing health expenditures, exposure to these expenditures have not been studied among health staffs and their families yet. So that our study has analyzed exposure to CHE (Catastrophic Health Expenditures) and factors affecting them among the health staffs affiliated to army medical universities in Tehran. Methods This study was a descriptive-analytical and cross-sectional study implemented in 2016. Among all health staffs of a university of medical sciences, the full details of 240 households (838 individuals) were collected by using a stratified random sampling method. The data gathering and analyzing process have been done based on WHO standard guideline. Finally, the odds ratio of CHE determinants is reported using logistic regression by backward elimination method and chi-square test. Results The results of this study showed that 7.5% (CI 7.3-7.7) of health staff households (54 individuals) are faced with CHE. The odds of exposure to CHE for households with 3 members and less, households with lower education level and households with two or more outpatient visits were significantly more than others (p less then 0.05). Households who have used dental services durin