ABSTRACT
Objective: To prepare ibuprofen sustained-release dropping pills, to evaluate the accumulative release percentage in vitro and to study the drug state in the base.Methods: With the drug content, mass ratio of water-soluble base to insoluble base and mass ratio of stearic acid to glyceryl monostearate as the investigation factors, and the comprehensive score of 2-hour and 10-hour cumulative dissolution rate as the evaluation index, a Box-Behnken response-surface method was used to screen the optimal formula of ibuprofen sustained-release dropping pills.The drug state in the matrix was examined by differential scanning calorimetry (DSC).Results: The optimal formula of ibuprofen sustained-release dropping pills was as follows: the drug content of 10%, water-soluble and insoluble matrix ratio of 4∶1, and stearic acid and glyceryl monostearate ratio of 3∶1.The maximum cumulative dissolution rate of ibuprofen sustained-release dropping pills was 78.85%.The DSC analysis showed that the drug crystallization peak disappeared in the sustained-release dropping pills, and formed a solid dispersion.Conclusion: The preparation has good sustained-release effect, and the preparation process is simple.
ABSTRACT
Objective To investigate the basic data of risk estimation of lung cancer among non-uranium miners in China.Methods 2836 workers from 24 mines in 9 provinces/regions were face-to-face interviewed to collect information including age at exposure,exposure duration,cigarette smoking among others.Results Age of the investigated non-uranium miners ranged from 17 to 72(36.9±8.0)years.The miners received low and poor education,3% of them were illiterate,58% with primary and middle school education,only 7% with junior college and higher education.Seventy-five percent of the uranium miners are migrant rural workers.Ethnic minority miners accoungted for 16% of all the investigated miners.Among the migrant rural workers age at initial exposure was estimated to be 29.6±8.0 years.By the time of the investigation,46.7% of the miners had worked in the mine for five years and longer,working years in the mine was 6.7±6.8 years with a median of 4.1years.3.4% of the non-uranium miners began the initial radon exposure in mines before their 18 years of old.17.5% of the investigated miners reported working more than 8 h every working day.Among the males,58.0% were current smokers with a median of 16 cigarettes per day.Age to begin the cigarette smoking was 20 years on average.Current smoking rate was age-dependent,the rate as high as 69.2% for the males aged 15-19 years.Current smoking rate was significantly statistically lower in coal mines than that in other mines,49.0% vs 62.5%.Compared with other miners,more frequent mechanical ventilations were reported by coal miners,Conclusions In China non-uranium mines,75% were migrant rural workers,by the time of the investigation about half of them had worked in the mines for at least five years.Non-uranium miners began their mining at 30 years on average,with a very small percentage of 3%,exposed to the mining radon before their 18 years.Current cigarette smoking rate in non-uranium male miners was the same as the general male population in China.