Comparative study of three biodegradable films for protein drug carrier / 国际生物医学工程杂志

Objective To prepare three kinds of biodegradable film materials used for protein drug carrier,and compare their degradation and drug release behavior.Methods Three different biodegradable and controlled release films,gelatin,chitosan oligosaccharides and crosslinked chitosan oligosaccharides films were prepared.Protein release behavior was determined by the Bradford.At the same time,degradation rate and swelling rate were tested,and the biocompatibility of film was investigated by MTT assay.Results The release time of crosslinked chitosan oligosaccharides film was 168 h,which was longer than that of chitosan oligosaccharides film,and different in different solution.The degradation rate and the swelling rate of crosslinked chitosan oligosaccharides was 60％ (360 h) and 110.45％,respectively,while the chitosan oligosaccharides membrane was 80％ (360 h) and 113.03％.The MTI assay revealed that the crosslinked chitosan oligosaccharides film had better biocompatibility.Conclusions By comparing different properties,the crosslinked chitosan oligosaccharides film is the best choice for protein drug carrier.

Effect of Chitosan Oligosaccharide on Enzymes for Cancer Chemoprevention / 대한암학회지

PURPOSE: Two types of chitosan oligosaccharides (COSs), COS I and COS II, were investigated for the effects on ascitic tumor and enzymes for cancer chemoprevention. MATERIALS AND METHODS: Chitosan oligosaccharides were administered once daily for 10 days after the tumor implantation. The change of body weight was observed for 20 days, and the survival rate of mice was determined after 21 days. Chitosan oligosaccharides were administered once daily for 10 days before the tumor implantation (1 106 cells). The number of ascitic tumor cells were measured at 6 days after tumor implantation. Chemopreventive potential of chitosan oligosaccharides was examined by the induction of quinone reductase and inhibition of cytochrome P450 1A1. RESULTS: Chitosan oligosaccharides exerted antitumor activity by inhibiting the growth of Ehrlich ascites tumor cells in vivo. Mice given Ehrlich cells and 10 or 100 mg/kg body weight of chitosan oligosaccharides had 33% survival after 21 days. Quinone reductase activity was increased with chitosan oligosaccharides. There were 26% and 33% inhibition in the activity of cytochrome P450 1A1 enzyme with the treatment of COS I and COS II, respectively. CONCLUSION: These results suggest that chitosan oligosaccharides has antitumor activity and cancer chemo preventive potential by inducing QR activity and inhibiting cytochrome P450 1A1.

Reactive Oxygen Radicals Generation and Apoptosis in HLF Cells Induced by PM10 / 环境与健康杂志

Objective The increasing evidences indicate that the inhalable particle matter (PM10) is responsible for respiratory and cardiovascular morbidity and mortality.Generation of superoxide anion,hydroxyl radical and apoptosis in HLF cells induced by PM10 were studied in this paper to present some data for elucidating the mechanism of effects of PM10.Methods The superoxide anion and hydroxyl radical were detected respectively by cytochrome C assay and apoptosis inspected with Annexin V-FITC/PI double staining by flow cytometry.Results PM10 could generate the superoxide anion and hydroxyl radical,with significant dose-dependent manners,and the levels of the superoxide anion as well as hydroxyl radical were decreased by chitosan oligosaccharides (COS),with the significant protection effects (P