微核实验评价碳化硅的潜在致突变性

背景：自制碳化硅陶瓷应用于临床前对其安全性进行相应评价。目的：通过微核实验检测自制碳化硅陶瓷对小鼠的致畸作用以评价其生物相容性。设计、时间及地点：随机对照动物实验,于2007-06/12在中国医科大学中心实验室完成。材料：N1H纯系小鼠80只按性别,体质量随机分成8组,每组10只：碳化硅0.02,0.002,0.0002mL/kg组、纯钛浸提液0.02,0.002,0.0002mL/kg组,生理盐水对照组,75mg/kg环磷酰胺阳性对照组。方法：各组均一次性给药,24h处死小鼠,抽取双侧股骨骨髓制备细胞悬液,推片二张,晾干、固定后浸入姬姆萨染液中染色。选择细胞完整,分散均匀,着色适当的区域在光学显微镜下计数。主要观察指标：计数1000个嗜多染红细胞的微核细胞数;嗜多染红细胞与正红细胞的比值。结果：环磷酰胺对照组微核率高于其他组（P〈0.01）。碳化硅陶瓷组和纯钛浸提液组微核率与生理盐水对照组比较,差异无显著性意义（P〉0.05）。碳化硅陶瓷组与纯钛浸提液组比较差异无显著性意义,嗜多染红细胞与正红细胞的比值均≥1。结论：自制碳化硅对小鼠无致畸作用,有较良好的生物相容性。

Teratogenic effect of self-made silicon carbide ceramic by micronuclei test

BACKGROUND:Safety of self-made silicon carbide ceramic(SiC)was evaluated before clinical application.OBJECTIVE:To study the biocornpatibility of low-Ni non-Be SiC alloy,detect its teratogenic effect to the mice with micronuclei test.DESIGN,TIME AND SETTING:Randomized controlled animal study was performed at Central Laboratory of China Medical Universitv from June tO December 2007.MATERIALS:86 mice were randomly divided into 8 groups by sex and body mass,including SiC(0.02,0.002,0.000 2 mL/kg)groups,Ni-Cr-Ni extract(0.02,0.002,0.000 2 mL/kg)groups,saline group,and 75 mg/kgcyclophosphamide group.with 10 mice in each group.METHODS:Mice in each group were administrated once and sacrificed after 24 hours.Bone marrow extracted from bilateral femur was used to make cell suspension.Slide specimens were fixed,dried,and dipped into Giemsa,The district which had complete cell,well-distributed,and well-coloration,was selected and counted under light mlcroscope,MAIN OUTCOME MEASURES:1000 micronucleated cells of polychromatic erythro-cytes(MNPCE)were counted,and ratio between polychromatic erythro-cytes(PCE)and normochromatic erythrocytes(NRBC),i.e.,P/N,wascalculated.RESULTS:Micronuclear rates in the cyclophosphamide group were higher than other groups(P＜0.01):however,there wete no significant differences in micronuclear rates among SiC ceramic group,Ni-Cr-Ni extract group,and saline group(P＞0.05);while,there were also no significant differences between SiC ceramic group and Ni-Cr-Ni extract grouP.The P/N value was≥1.CONCLUSION:The self-made SiC has no teratogenic effect to mice and shows great biocompatibility