Effects of different spacers on induced membranes in Masquelet technique / 中华创伤骨科杂志

Bone defects,a challenge in orthopedics,are mostly caused by severe trauma,bone tumor and bone infection.Their chief treatments include bone graft,distraction osteogenesis and Masquelet technique.Compared with other treatments,Masquelet technique is simpler and causes fewer complications,especially for infectious defects.In the first stage of Masquelet technique,a bone defect is filled with bone cement.The spacer most commonly used is polymethylmethacrylate(PMMA).PMMA can form induced membrane rich in blood vessels and bioactive components promoting osteogenesis,but it is not biodegradable,lacks bone conductibility,has an obvious thermal effect during operation,and is hard to remove in the second phase of Masquelet technique.Calcium sulfate and calcium phosphate bone cement are biodegradable materials which overcome the defects of PMMA due to their biological absorbability,bone conduction and bone inducement.It is possible for them to replace PMMA in Masquelet technique,but their poor mechanical strength limits their application.There is clinical evidence showing that calcium sulfate bone cement can form obvious induced membrane.As calcium silicate cement can also form a layer of fibrous tissue around the shell,it may be applied in orthopaedic surgery after improvement as a potential filling agent.A structure like induced membrane can form around a silicone prosthesis,and it functions similarly as induced membrane around PMMA and is more resistant to a radiation environment.Silicone has obvious advantages over PMMA after resection of bone tumor.Spacers used in the first stage of Masquelet technique have important effects on formation process and quality of induced membranes.By comparing membranes induced by different types of spacer,we can know more about the effects of spacers on induced membranes in the first stage of Masquelet technique and thus discover the most suitable spacers good for fracture healing and membrane formation.

Effect of enalapril maleate and folic acid tablets in the treatment of H type hypertension and its influence on blood homocysteine / 中国基层医药

Objective To study the clinical effect of enalapril maleate and folic acid tablets in the treatment of H type hypertension, and to observe the blood homocysteine(Hcy), to provide the basis for clinical diagnosis and treatment.Methods 126 patients with H type hypertension were selected.They were divided into study group and control group according to the random number table method,63 cases in each group.The control group was given enalapril maleate, the study group was given enalapril maleate and folic acid tablets.The clinical efficacy of the two groups was compared.The systolic blood pressure, diastolic blood pressure and Hcy level before and after treatment in two groups were observed.Results The total effective rate of the study group was 90.5%(57/63),which of the control group was 74.6%(47/63),the difference was statistically significant(x2=15.371,P0.05).The systolic pressure after treatment of the two groups were (129.3±5.7)mmHg and (137.9±4.9)mmHg, the diastolic blood pressure were (81.5±3.6)mmHg and (89.6±5.1)mmHg, the differences were statistically significant compared with before treatment(t=8.969,7.851,7.343,6.987,all P0.05), after treatment Hcy levels of the two groups were (8.93±0.63)μmol/L and (15.35±0.57)μmol/L respectively, the differences were statistically significant compared with before treatment(t=8.097,8.031,all P<0.05),the difference between the two groups was statistically significant(t=7.573,P<0.05).Conclusion Enalapril maleate and folic acid tablets in the treatment of H type hypertension has good clinical effect, can significantly lower blood pressure, improve Hcy level.

Corrosiveness of Ti-Fe-Mo-Mn-Nb-Zr alloys in various pH lactic acids / 生物医学工程学杂志

Variation in pH value of oral cavity circumstance causes decayed tooth. In this paper, corrosions of Ti-Fe-Mo-Mn-Nb-Zr dental alloys in various pH lactic acids were studied by immersion test. In the case of pH=4, which is an acidity slightly larger than that causes decayed tooth, Ti-Fe-Mo-Mn-Nb-Zr alloys are entirely corrosion-resistant, and the corrosion type is pitting. With the increase in acidity, the corrosion-resistance of Ti-Fe-Mo-Mn-Nb-Zr alloys deteriorates, and the corrosion type changes from pitting to intergranular corrosion. Fe ion is the most dissolved substance in impregnation, which means Fe goes against the corrosion-resistance of Ti alloys. Both results of thermodynamics calculation and X-ray photoelectron spectroscopy have shown that Mn2O3, Nb2O5 and TiO2 form oxide film on the surface of Ti-Fe-Mo-Mn-Nb-Zr alloys.

Evaluation on biocompatibility of Ti-Fe-Mo-Mn-Nb-Zr alloy / 生物医学工程学杂志

In this study, the general toxicity tests including acute toxicity test, haemolysis test, MTT assay of Ti-Fe-Mo-Mn-Nb-Zr alloys were carried out. The morphology of these cells was also observed under phase-contrast microscope. By using X-ray photoelectron spectroscopy(XPS), the kind and mol% of element in surface film were studied. The kind and concentration of element in dipping fluid were investigated by ICP atomic emission spectrometry. The results showed the primary component is TiO2 in surface film. The dipping fluid of Ti-Fe-Mo-Mn-Nb-Zr alloys contains Fe 0.2-1.07 mg/l and Mn 0.16-0.5 mg/l; such dental materials are beneficial to health. No cytotoxic effect was disclosed by in vitro and in vivo tests. The level of cytotoxicity was grade 0 and 1; the haemolysis degree was 0.558%-0.642%, i.e. less than 5%. The cells growing in the extract showed normal morphology. These data indicate that Ti-Fe-Mo-Mn-Nb-Zr alloy, as a dental material, has good biocompatibility.