Preparation and characterization of polymethylmethacrylate-based magnetic bone cements containing micron carbonyl iron powder / 中国组织工程研究

BACKGROUND:Magnetic bone cements have been used to treat bone metastasis in Japan, which are made by adding Fe3O4 nanoparticles to bone cements. Magnetic bone cements containing micron carbonyl iron powder have not been reported. OBJECTIVE:To prepare polymethylmethacrylate-based cements containing carbonyl iron powder, and to test the magnetic characterizations and the heat-generating abilities of al samples according to ISO 5833 standard in vitro. METHODS:The carbonyl iron powder was mixed with polymethylmethacrylate-based bone cement power to prepare magnetic bone cements containing 0%, 20%, 30%, 40%, and 50%carbonyl iron powder, respectively. The setting time, polymerization temperature, compressive strength, magnetic property and in vitro heat-generating ability were tested. RESULTS AND CONCLUSION:The setting time and polymerization temperature were increased with the increased content of carbonyl iron powder. The highest polymerization temperature of each sample was 65-70 ℃. The increased content of carbonyl iron power could not change the highest polymerization temperature but delay its appearance. The compressive strength of each sample was higher than 60 MPa, and moreover, the compressive strength of the pure polymethylmethacrylate-based bone cement was higher than 60 MPa, which met the ISO 5833 standard. The saturation magnetic intensity was increased with the increasing of carbonyl iron power content. The heat-generating ability of magnetic bone cements had a positive correlation with the magnetic field strength and the content of carbonyl iron powder.

Research progress on anti-tumor and immunity activity of CpG / 国际肿瘤学杂志

CpG motifs are unmethylated oligodeoxynucleotides,and its core sequences are composed of unmethylated cytosine and unmethylated guanine.CpG motifs can induce the immune response by activating a variety of immune cells against diseases.The changes of CpG structure will increase the biological activities of CpG,and then enhance the therapeutic effect of CpG as the immuno adjuvant and the sensitizer of radiotherapy and chemotherapy in cancer treatment