New Design of Revivent TC System / 中国医疗器械杂志

Left ventricular aneurysm (LVA) is a common complication of myocardial infarction. Traditional medical and surgical treatments are not effective or require high doctors' operational skills and patients' physical fitness. With the development of minimally invasive medical devices, it becomes possible for revivent TC system to treat LVA and reconstruct the left ventricle. This study introduces an existing product and its defect when used. From the perspective of clinical needs, we propose a new design of revivent TC system which realizes accurate force measurement and simplifies surgery.

In vitro bioactivity and degradability of injectable poly(propylene fumarate)/beta-tricalcium phosphate bone cement / 中国组织工程研究

BACKGROUND:Poly(propylene fumarate) (PPF) can crosslink at room temperature, andβ-tricalcium phosphate (β-TCP) has good biocompatibility, but PPF/β-TCP composite bone cement has not yet been systematical y studied. OBJECTIVE:To prepare PPF/β-TCP composite bone cement and to explore its in vitro bioactivity and degradability. METHODS:β-TCP and PPF were respectively synthesized by liquid-phase precipitation and a two-step method, and PPF/β-TCP composite bone cement was prepared through mixing PPF withβ-TCP. The in vitro bioactivity of PPF/β-TCP was compared with the commercial poly(methyl methacrylate) (PMMA) through the ability of forming hydroxyapatite after immersed in simulated body fluid for 7 days. The in vitro degradability of PPF/β-TCP was studied via investigating the transformation of pH values, water uptake and mass loss, compressive strength and morphology at each time point. RESULTS AND CONCLUSION:There were hydroxyapatites formed on the PPF/β-TCP material, but none on the commercial PMMA material. The pH values of the PPF/β-TCP were stable in PBS for 63 days, indicating its degradation is moderate;the mass loss was up to 13.5%after 84 days. Scanning electron microscope displayed the degraded PPF/β-TCP surface, and its compressive strength was decreased gradual y, which good for the integrity and sustainability of mechanical properties during degradation. These results suggest that PPF/β-TCP bone cement holds mineralization and degradability in vitro.