RESUMO
objective To introduce the design concept and structure of a new type of lumbar intervertebral fusion cage ,and to e-valuate its biomechanical properties .Method A partially bioasorbable interbody fusion cage(PBIFC) made of nano hydroxyapatite and poly amino acid /calcium sulfate copolymer materials was developed .Range of motion(ROM ) ,compressive load ,and pull-out test on flexion ,extension ,lateral bending ,and torsion moment on fresh calf L3/L4 specimens of functional spinal union were carried out of iliac bone group ,PBIFC group ,and nano hydroxyapatite/polyamide 66(nHA/PA66) group .Result Of each movement ,the ROM value of iliac bone group are higher than the other two groups ,the difference was statistically significant (P0 .05) .The pull-out strength of PB-IFC group are higher than iliac bone group ,and the difference was statistically significant (P0 .05) .The compressive load of iliac bone group was lower than that of two cage group ,the difference was statistically significant (P0 .05) .Conclusion With good implant stability ,pull-out resistance ,and compression resistance performance ,PBIFC can meet the biomechanics requirements of clinical implant .
RESUMO
Lysostaphin, a specific endopeptidase enzyme derived from Staphylococcus aureus, is a bactericidal agent against Staphylococcus and difficult to be drug-resistant. This study established the monoclonal antibody affinity chromatography to obtain lysostaphin of high purity for drug-use standard. The purified Lysostaphin was of > 95% purity and its recovery rate more than 90%. Moreover, the affinity column kept its efficiency of purification invariable after more than 30 times repeat. Also, the dye release assay validated that the purified lysostaphin had significant bactericidal activity. This method was simple and of high efficacy for the lysostaphin purification and showed its potency in commercial production.