Objective This objective of the study was to analyze the factors related to being recaptured and condom use among low-fee female sex workers (FSWs) to provide reference in developing human immunodeficiency virus (HIV) intervention strategy. Methods Physical examination certificates were designed by Zhongshan County Center for Disease Control and Prevention to record HIV and syphilis test results for low-fee FSWs from 2013 to 2015. Low-fee FSWs were asked to show physical examination certificates in the next intervention and test. Multivariate Logistic regression was used to analyze factors associated with being captured with physical examination certificates. Generalized linear mixed model was used to analyze factors associated with condom use with clients. Results A total of 220 low-fee FSWs were recruited by using physical examination certificates and received 389 interviews from 2013 to 2015. The proportions of HIV positive and syphilis positive were 4.2% (9/213) and 30.0% (64/213) respectively among those who had HIV and syphilis test. Results of multivariate Logistic regression analysis showed that low-fee FSWs who had been FSWs for more than 4 years (OR=2.95, 95% CI：1.35-6.45), and worked in the local county in the past 30 days (OR=11.74, 95% CI: 5.26-26.20), were more likely to be captured with physical examination certificates. Results of generalized linear mixed model showed that those who were captured at least once (OR=3.33, 95% CI: 1.34-8.27), had junior middle school education and above (OR=22.79, 95% CI: 3.75-138.57), had high HIV knowledge (OR=3.57, 95% CI: 1.52-8.38), and charged more than 30 yuan for vaginal sex (OR=30.68, 95% CI: 12.57-74.90), were more likely to use condom consistently. Conclusions Physical examination certificates could be used for low-fee FSWs surveillance and intervention and tracking their HIV and syphilis status. The intervention strategy should take these into consideration.

OBJECTIVE This study aimed to optimize polysaccharides extraction from Urena lobata L.and investigate its antioxidant activity.METHODS The mathematical model was established by re-sponse surface method (RSM) based on the results of single factor experiments, using polysaccha-rides extraction rate as response value,and using the ratio of water to material,cellulase concentra-tion,extraction temperature and time as experimental factors,which was used to screen optimum poly-saccharide extraction conditions from Urena lobata L.. Antioxidant activity of polysaccharides was stud-ied by DPPH and ·OH free radical elimination method. RESULTS The optimum conditions obtained by RSM were as follows:the cellulase level was 10.8 g·L-1,extraction time duration was 72 min,the ra-tio of water to feedstock was 7 mL·g-1,extraction temperature was 43℃,the pH value was 5.0.Under the optimal conditions, there was a difference of less than 5％ between predicted extraction rate 13.37％ and experimental extraction rate 13.32％. The polysaccharide yield was most significantly af-fected by cellulase concentration,followed by extraction time,water to material ratio and extraction tem-perature.IC50of DPPH and·OH were 1.082 g·L-1and 3.202 mg·L-1,respectively.Antioxidant activity of sample polysaccharides was weaker than those of vitamin C. CONCLUSION The polysaccharide extraction process from Urena lobata L. by cellulase enzymolysis approach was obtained, which was convenient and feasible,and extracted polysaccharides had good free radical scavenging activity.