Mediation of abdominal obesity on the association between cigarette smoking and β-cell function / 中华流行病学杂志

Objective To confirm the effect of cigarette smoking on β-cell function, and further investigate the mediation effect of abdominal obesity. Methods Participants would include 1440 Chinese smokers who had participated in a community-based chronic disease screening project in Guangzhou and Zhuhai from 2006 to 2007. They were interviewed with structured questionnaire on their socio-demographic status and smoking behaviors. Waist-to-hip ratio (WHR) and fasting serum C-peptide concentration were also measured. Results After adjustment for the potential confounding factors, when compared with smokers with consumption 1-10 cigarettes/day, smokers with consumption of 11-20 cigarettes/day (adjusted OR=1.53, 95%CI: 1.22-1.90) or ＞20 cigarettes/day (adjusted OR=1.92, 95%CI: 1.32-2.79) had significant higher risks to get C-peptide concentration larger than its median. Furthermore, 37.54% of the effect of cigarette smoking on C-peptide concentration was partially mediated by abdominal obesity. Conclusion Cigarette smoking might be a risk factor for β-cell dysfunction and abdominal obesity.

Single cell gel electrophoresis of a magnesium alloy coated with beta-tricalcium phosphate / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the genotoxicity of a magnesium alloy coated with beta-tricalcium phosphate (beta-TCP).</p><p><b>METHODS</b>Four groups were designed. In the first group, AZ31B magnesium alloy surface was coated with beta-TCP using chemical bath deposition, and in the second group magnesium alloy was tested. The other two groups were negative control (pure titanium) and positive control groups (0.5 mg/L bleomycin). Single cell gel electrophoresis was adopted to investigate genotoxicity of the alloy samples in different groups, and 60 cells from each group were analysed. Tail moment and tail DNA percentage were used as reliable indicators to show DNA damage in lymphocytes induced by every testing sample. Student-Newman-Keuls (SNK) test was used to compare results from 4 groups.</p><p><b>RESULTS</b>There were no significant differences in tail moment and tail DNA percentage between magnesium alloy group [(0.52 +/- 0.12), (6.82 +/- 1.81)%] and magnesium alloy coated with beta-TCP group [(0.51 +/- 0.12), (6.89 +/- 1.93)%, P > 0.05]. Tail moment and tail DNA percentage in negative group were (0.47 +/- 0.14) and (6.29 +/- 1.64)%, and tail moment and tail DNA percentage in positive group were (5.17 +/- 1.23) and (22.09 +/- 4.51)%.</p><p><b>CONCLUSIONS</b>No significant increase was found in DNA damage in lymphocytes induced by magnesium alloy coated with beta-TCP.</p>