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This study developed an active loading method for encapsulating chloroquine diphosphate (CQ) into liposomes. The effects of different formulation factors on the encapsulation efficiency (EE) and the size of CQ liposomes were investigated. These factors included the internal phase of liposomes, the external phase of liposomes, the ratio of drug to soybean phosphatidylcholine (drug/SPC), the ratio of cholesterol to soybean phosphatidylcholine (Chol/SPC), and the incubation temperature and time. The EE (93%) was obtained when using drug/SPC (1:50 mass ratio), SPC/Chol (1:5 mass ratio) at 0.10 M citrate-sodium citrate buffer (pH 3.6). As 5 mol% methoxypoly(ethylene glycol)(2,000) cholesteryl succinate (CHS-PEG(2000)) or distearoyl phosphatidylethanolamine-poly (ethylene glycol)(2,000) (DSPE-PEG(2000)) was added, the size of particle was reduced and the EE was improved. Freeze-drying with 5% trehalose as a cryoprotectant was carried out to achieve long-term stability. The drug release studies were performed in vitro simulating the desired application conditions, such as physiological fluids (pH 7.4), tumor tissues (pH 6.5) and endosomal compartments (pH 5.5). The release of CQ from the liposomes prepared via remote loading showed the significant pH-sensitivity and retention properties, which favored the application of liposomal CQ at tumor tissues and endosomal compartments.

The degradation performance and tissue compatibility of polyphosphazene/polyester or polyanhydride (PGP/PLGA or PGP/PSTP) blend films were investigated in mice. The results showed that the blend degradation rate could be regulated by adjusting PLGA or PSTP content in the blends. For example, the weight loss of PGP/PLGA (70:30 by wt) film was 68.4% after 55 days, whereas that of PGP/PSTP (70:30 by wt) was 88.5% only after 12 days. Also the mechanisms for in vivo degradation of blends of PGP/PLGA and PGP/PSTP were hydrolysed enzymatically and non-enzymatically, respectively. The tissue compatibility of PGP/PLGA was better than that of PGP/PSTP, and an increase of the percentage of PGP in PGP/PSTP blends would help improve the tissue compatibility. These findings suggested that polyphosphazene blends be potential materials applied in medical field.

Objective: To study the respiratory system injury in fur processing environment., Methods: Environmental fungal survey was conducted in the fur processing procedures. Investigation of respiratory symptoms and chest X-ray examination were also carried out in 138 fur processing workers and 40 control workers. At the same time, the serum antibodies to fungi were analyzed by ELISA., Results: Fungal number(629-3,681 cfu/m3) in fur processing procedures was much higher than those in the control environment. Cladosporium and Alternaria were the leading strains of fungi in fur processing procedures. The rates of respiratory symptoms(cough, sputum, chest tightness, dyspnea, and fever) in fur processing workers were higher than those in the control workers. The rates of the symptoms in female workers were 37.9%, 28.4%, 10.5%, 22.1%, 4.2%, respectively. Abnormalities of chest X ray were found in 7 workers. The serum antibodies to Cladosporium and Alternaria(A450 nm 0.631, 0.724, respectively) in fur workers were significantly higher than those in the control workers(P < 0.05). The positive rates of the antibodies to Cladosporium and Alternaria(44.2%, 42.8%) were significantly higher than those in the control workers(P < 0.01)., Conclusion: Cladosporium and Alternaria may be the pathogens of occupational respiratory diseases in fur processing workers.