Carrera P, Orsini S, Terzoli G, Brambati B, Simoni G
Laboratorio di Citogenetica, Istituti Clinici di Perfezionamento, Milano, Italy.
Prenat Diagn. 1990 Mar;10(3):141-8. doi: 10.1002/pd.1970100302.
A study was done to evaluate the effects of diagnostic ultrasound on sister chromatid exchange (SCE) in first-trimester chorionic villi under controlled technical conditions. Chromosome analysis was performed by the direct method using spontaneous mitoses from the cytotrophoblast layer, and SCE visualization was accomplished by a 72 h treatment with 5-bromodeoxyuridine (BrdU) at a concentration of 10 micrograms/ml. The slides were stained with acridine orange. Immediately before first-trimester chorionic villus sampling, a group of ten pregnant women was exposed to diagnostic ultrasound for 20 min (in vivo exposure). This group of patients was compared with a control group who were not exposed. A mean value of SCE/cell frequency of 4.2 +/- 0.2 was found in the exposed pregnancies, while a value of 3.7 +/- 0.2 was observed in the control group. After in vitro exposure of chorionic villi obtained from elective abortions, the frequency of SCE/cell did not differ significantly among samples with different exposures (1, 2, and 3 h) and controls. The positive control (mitomycin C) yielded a significant increase in SCE frequency.
在可控技术条件下开展了一项研究，以评估诊断性超声对孕早期绒毛膜绒毛姐妹染色单体交换（SCE）的影响。采用直接法，利用细胞滋养层的自发有丝分裂进行染色体分析，通过用浓度为10微克/毫升的5-溴脱氧尿苷（BrdU）处理72小时来实现SCE可视化。玻片用吖啶橙染色。在孕早期绒毛取样前，一组10名孕妇接受了20分钟的诊断性超声检查（体内暴露）。将该组患者与未暴露的对照组进行比较。在暴露的妊娠中，SCE/细胞频率的平均值为4.2±0.2，而对照组为3.7±0.2。对选择性流产获得的绒毛膜绒毛进行体外暴露后，不同暴露时间（1、2和3小时）的样本与对照组之间的SCE/细胞频率无显著差异。阳性对照（丝裂霉素C）使SCE频率显著增加。
