两例事故受照者染色体畸变分析及生物剂量估算

应用外周血淋巴细胞染色体畸变形和CB微核分析方法,对2000年河南许昌“3.06”^60Co辐射事故1例受照（A）和2000年河南开封“6.26”辐射事故一例过量放射性核素内污染致γ射线照射受照（B）的生物剂量进行估算。结果表明,“A”和“B”两例受照依据双＋环率估算的剂量分别为1.44Gy和0.15Gy,CB微核率估算的剂量分别为1.43Gy和0.22Gy,与用物理方法估算的剂量比较接近,亦与放射损伤的临床诊断一致。泊松分布检验证实,“A”偏离泊松分布,受到不均匀照射。提示染色体畸变和CB微核分析是非常可靠的生物计量估算方法。     

60Co事故受照人员远期细胞遗传学效应观察

对三例钴源事故受照人员照后6(7)年和11(12)年两次细胞遗传学随访结果表明,两次随访受照者染色体畸变率分别为4.29%和3.63%,均显著高于对照组(P<0.01),但两次随访间未见显著差异(P>0.05),而且第一次随访染色体畸变是以双+环和无着丝粒断片为主,第二次随访是以易位、缺失和倒位为主;两次随访受照者微核率分别为4.17‰和1.17‰,第二次随访微核率明显下降(P<0.01)。提示随着照后时间推移, 非稳定性染色体畸变逐渐丢失,稳定性染色体畸变仍保持在较高水平。     

60Co事故受照人员远期细胞遗传学效应观察

对三例钴源事故受照人员照后6(7)年和11(12)年两次细胞遗传学随访结果表明,两次随访受照者染色体畸变率分别为4.29%和3.63%,均显著高于对照组(P<0.01),但两次随访间未见显著差异(P>0.05),而且第一次随访染色体畸变是以双+环和无着丝粒断片为主,第二次随访是以易位、缺失和倒位为主;两次随访受照者微核率分别为4.17‰和1.17‰,第二次随访微核率明显下降(P<0.01)。提示随着照后时间推移, 非稳定性染色体畸变逐渐丢失,稳定性染色体畸变仍保持在较高水平。 Abstract：　The analyses of chromosome aberrations and micronuclei in peripheral blood lymphocyte were performed in 3 cases exposed to 60Co radiation accident in 6(7) years and 11(12) years after irradiation. The results show that the frequencies of chromosome aberrations in exposed cases were 4.29% in 6(7) years and 3.63% in 11(12) years after irradiation, respectively, and the difference was not significant in the two times follow-up study. Most of the chromosome aberrations were acentric and dicentric chromosomes in first time follow-up study, and translocation, deletion and inversion chromosomes in second time follow-up one. The frequencies of micronuclei in exposed group were 4.17‰ and 1.17‰ in the two times follow-up study, respectively, and the rates of micronuclei in second time follow-up study were much lower than that in first one. The results indicated that the unstable type aberrations were gradually lost as time goes on ,and the level of stable type aberration was of high degree.     

河南地区新生儿染色体畸变的流行病学调查

为了解河南地区群体染色体畸变发病率情况,研究可能与染色体畸变有关的 因素及再现风险。综合运用多种现代细胞遗传学技术对3068例新生儿进行染色体核型分析,并对染色体核型异常者进行家系分析、再现风险及病例对照研究。结果表明:河南地区新生儿染色体畸变发生率为2.74%;其中13.1%由亲代遗传,86.9%为子代新生突变;病例组84例中有46例再次生育,再现染色体畸变8例,染色体畸变再发生率为17.39%;孕妇高龄、异常妊娠史、妊娠期间致畸因素接触史及胎儿宫内发育迟缓等可能是新生儿染色体畸变的高危因素。 Abstract:To investigate the incidence of chromosomal aberrations and recurrence risk in Henan and inqure into the risk factors resulting in newborn chromosomal aberrations,3 068 newbors were karyotyped with several advanced cytogenetic methods.The result showed the incidence of chromosomal aberrations was 2.74%(84cases),only 13.1% out of 84 aberrations were transmitted from the previous generation and 86.9% arose de novo.Within 46 second babies being born after their sibling with chromosomal aberrations,8 were abnormal karyotypes,the recurrence rate was 17.39%.The case-control study showed mothers with advanced age,mothers exposure to detrimental factors in pregancy and mothers with abnormal reproductive histories,intranter growth retardation may be the risk factors resulting in chromosomal aberrations.     

四硼酸钠诱导蚕豆根尖细胞微核及染色体畸变的实验研究

本文以蚕豆为实验材料,用不同浓度的四硼酸钠处理蚕豆根尖。通过对蚕豆根尖细胞镜检观察结果表明:四硼酸钠可诱导微核的形成及染色体畸变的产生,实验组与对照组差异极为显著,即细胞微核率随处理时间的延长有所增加,50与200ppm浓度诱导细胞微核率没有明显差异。此外,本文对微核的形成与染色体畸变的相关性进行了讨论。     

亚硫酸氢钠（SO2）对人血淋巴细胞染色体畸变,姊妹染色单体互换及微核的效应

本文研究结果表明,亚硫酸氢钠（二氧化硫）能够引起人血淋巴细胞姊妹染色单体互换（ＳＣＥ）和微核（ＭＮ）率的增加,可使淋巴细胞有丝分裂周期延迟及细胞分裂指数下降,且这些作用有显著的剂量效应关系。结果指出,亚硫酸氢钠在低浓度下仅引起细胞染色单体型畸变,在高浓度下既可引起染色单体型畸变,又可引起染色体型畸变。结果还指出,亚硫酸氢钠对染色体畸变（ＣＡ）和ＭＮ的诱发效应有明显的个体差异。硫酸钠未能引起上述细胞     

应用染色体涂染技术分析两例染色体结构异常 Analysis of the Structure of Abnormal Karyotypes by Using Chromosome Painting

为了确定两例细胞遗传学提示染色体结构异常的核型,应用通过显微切割技 术构建的人类18号和7号染色体探针池,分别对这两例病例的中期分裂相进行染色体涂染,结合显带染色体,确定两者核型分别为46,XY,t(3;18) (q12;q21)和46,XX,dir ins(1;7)(p3104;q34q36)。染色体涂染技术是染色体显带技术的重要补充和发展,为染色体结构异常提供了一种直观、准确的检测手段,在遗传咨询和产前诊断方面有重要作用。 Abstract:In this study,chromosome painting technique was performed to analyse the abnormal karyotypes of two carriers.Chromosome 18 and 7 specific libraries,which were generated by chromosome microdissection technique,were used as probe pools to hybridize the carriers metaphase chromosomes respectively.Unlabled human genomic DNA was used to inhibit the hybridization of sequences in the library that bind to mutiple chromosomes.Structure abnormality was detected clearly in metaphase.Combined with the banding chromosomes,we concluded that their karytypes were 46,XY,t(3;18)(q12;q21)and 46,XX,dir ins(1;7)(p3104;q34q36).Chromosome painting,as a direct and concise method in analysing chromosome structure abnormality,is an important complement and development of chromosome banding technique,and has important application in genetic counselling and prenatal diagnosis.     

重铬酸钾对蚕豆根尖细胞致畸效应的研究

以蚕豆根尖为材料,研究重铬酸钾对蚕豆根尖细胞的致畸效应。采用蚕豆根尖细胞的微核试验和染色体畸变试验方法,以不同浓度的重铬酸钾为诱变剂,测定蚕豆根尖细胞的微核率和染色体畸变率。结果表明：重铬酸钾能诱发较高频率的微核率,即在一定浓度范围内,其微核率随重铬酸钾处理浓度的升高而增加,但高于一定浓度后反而呈下降趋势;不同浓度的重铬酸钾均使蚕豆根尖细胞有丝分裂指数增大;重铬酸钾还能诱导蚕豆根尖细胞产生较高频率的染色体畸变,且产生多种类型的染色体畸变。结论是重铬酸钾对蚕豆根尖细胞具有明显的致畸效应。Abstract：We studied the aberrant effects of different concentrations of potassium dichromate on Vicia Faba root tip cells. The micronucleus and chromosome aberration assay was conducted to determine the micronucleus rate and chromosome aberration rate of Vicia faba root tip cells induced by potassium dichromate. The result indicated that potassium dichromate could increase the micronucleus rate of Vicia faba root tip cells. Within certain range of concentration the rate of micronucleus was found to be increased with the increase of potassium dichromate concentration,but beyond this range the rate of micronucleus decreased with further increase of potassium dichromate concentration. The potassium dichromate at different concentrations could increase the cell mitosis index. Besides,it also caused various types of chromosome aberration,and the rates of chromosome aberration were always higher than that of the control group. The conclusion of this study was that potassium dichromate has obvious teratogenic effect on vicia faba root tip cells.     

中间偃麦草单条染色体分离及体外扩增

本研究利用微细玻璃针法从减数分裂中期I的花粉母细胞中分离回收了携带小麦抗黄矮病基因的中间偃麦草染色体2Ai－2。将目标染色体放入装有蛋白酶K消化液的0.5ml小离心管中,用Sau3AI酶切,在DNA片段的末端连接接头后,进行 PCR扩增。扩增产物经琼脂糖凝胶电泳分析,DNA片段的大小在150～3000bp之间,而大部分集中在200～1500bp之间。 Abstract:A simple method was used to adapt refined needles for the collection of Th.intermedium 2Ai－2 chromosome carrying BYDV (barley yellow dwarf virus) resistance gene from meiosis－metaphase spreads .The aimed chromosome was put into a 0.5ml Eppendorf tube,deproteinized with proteinase K,digested with Sau3AI,and link－adaptors were ligated to the ends of the DNA fragments.After amplification by PCR,size distributions of the PCR products were analyzed by agarose gel electrophoresis and smears of DNA were revealed that the size ranged from 150bp to 3000bp with predominant fragments at about 200～1500bp.     

微核形成与细胞周期关系的初步研究 Ⅲ.丝裂霉素c诱发人淋巴细胞染色体畸变与不同周期阶段的微核形成

为了研究染色体畸变与微核形成的关系,本实验用不同浓度的丝裂霉素C(MMC,0.025—0.4μg/ml),处理人外周血淋巴细胞,观察中期染色体畸变与不同细胞周期形成的微核间的关系。获得如下主要结果:(1)MMC诱发的染色体畸变细胞率(ACF),未经培养的G_0期淋巴细胞的微核细胞率(NC-MNCF)以及培养的淋巴细胞的微核细胞率(C-MNCF),在一定剂量范围内均呈剂量依赖性增加,并可用幂回归方程描述;(2)微核形成与染色体畸变全然无关的NC-MNCF,和C-MNCF一样,与ACF呈良好的正相关;(3)用胞质分裂阻滞(CB)法,检测MMC诱发的CB-MNCF,较C-MNCF无显著提高,MNCF/ACF的比值较小,并随着MMC剂量增加从0.15左右降到0.03。所有上述结果表明,不能简单理解微核形成与染色体畸变间的关系,在分裂的细胞群体中,中期染色体畸变可能仅是微核形成的一种来源。     

激光及γ射线对有丝分裂染色体畸变感应现象的比较

波长514nm的激光照射可用于研究激光导致有丝分裂染色体畸变的效应。本文提供了一种新的辐照系统,能用于研究突变的感应现象,并与从γ-线辐射源获得的结果进行了比较。 Abstract:Laser irradiation at wavelength 514 nm was used to study the effect of lasers in inducing chromosomal aberrations at mitosis.This study offers a new radiation system which could be used for the induction of mutations.Results are compared with those obtained from studies using γ-rays as irradiation source.     

辐照大麦M~1花粉母细胞染色体畸变及其与M~2 性状变异的关系

大麦种子经5种不同剂量γ射线辐照后, M1植株的花粉母细胞出现多种染色体畸变类型,例如后Ⅰ、后Ⅱ中出现桥、落后,后Ⅰ中出现不对称分裂,后Ⅱ中出现不同步分裂,中期Ⅰ出现环状四价体,末期Ⅰ中有三极分裂和微核,四分体中出现微核且有的微核独立于四分体,从而形成多分体。花粉母细胞的染色体畸变率随剂量的增高而升高,二者呈极显著直线相关关系。 M1花粉母细胞的染色体畸变率与M2的叶绿素突变率及农艺性状变异率呈显著或极显著指数函数关系。 M2花粉母细胞的染色体畸变率低于M1。 Abstract:Barley seeds were irradiated with five different doses of 60 Co-γ ray.There were many kinds of chromosome aberration in pollen mother cells,such as bridge,laggards in anaphase I and anaphase II,asymmetrical division in anaphase I and asynchronous division in anaphase II,ring quadrivalent in metaphase I,three pole division and micro-nuclei in telophase I,micro-nuclei in tetrad and some micro-nucleus separates from the tetrad to form polyad.The frequency of chromosome aberration in pollen mother cells of M1 increased with the increase of dose.There was a significant linear relationship between them.The frequencies of agronomic character mutation and chlorophyll mutation in M2 significantly correlated with the frequencies of chromosome aberration in pollen mother cells of M1 and showed an exponential function.The chromosome aberration frequency in pollen mother cells of M2 was lower than that of M1.     

三氧化二砷（As2O3）对蚕豆根尖毒性效应的细胞遗传学研究

本文以蚕豆根尖为材料,研究不同浓度As2O3在不同的处理时间内对蚕豆胚根根尖的细胞遗传学毒性效应。结果表明：不同浓度的As2O3在不同处理时间内均能诱发较高的微核率和染色体畸变率,并能有效地积累中期分裂相,阻止其进入后期与末期。结论是As2O3对蚕豆根尖细胞具有明显的细胞遗传学毒性效应,并具有积累有丝分裂中期细胞的效应。 Abstract:The cytogenetic toxic effects of different concentration of As2O3 within different time on the cell of Vicia Faba root tip were studied.The results indicate that the different concentrations of As2O3 can induce high frequency of micronucleus and chromosome aberration.Besides,it can accumulate the metaphases in mitosis efficiently and prevent the cells from continuing their cell cycle.It shows that As2O3 has marked cytogenetic toxic effect on the root tip cells of Vicia Faba,and effect of accumulating the metaphases in mitosis.     

小鼠着丝粒DNA探针对流式仪分选微核的染色体组成的初步研究

本文报道用作者建立的流式细胞仪红细胞微核自动检测技术,将染色体断裂剂丝裂霉素C(MMC)和非整倍体毒剂秋水仙碱(COM)诱导的大量微核分选在载玻片上,然后使用小鼠着丝粒γ-卫星DNA探针(约为234bp),对分选微核进行荧光原位杂交(FISH),以显示微核(MN)内着丝粒的情况,进而判定M N是由整条染色体还是由染色体断片组成。结果MN内着丝粒荧光阳性比例为COM50.1%,MMC 22.3%。两者相差显著,藉此方法可以准确有效地将两类毒剂区分开。 Abstract:Basis on auther’s new automatic flow cytometric technique for micronuclei,a lot micronuclei induced by clastogen Mitomycin C and aneugen colcemid were collected on slides using sorting function of flow cytometry,them the centromere Gamma satellite DNA probes of mouse (about 234bp) was used to do in situ hybridization for micronuclei,furthermore,the kinetochores of micronuclei can be showed,and the micronuclei which consist of the whole chromosomes or the chromosome fragments,can also be indicated.The results showed that 50.1% MN induced by COM and 22.3% MN induced by MMC had the positive fluorescent singles.There are significant difference between them,this means it is possible to distinglish clastogens and aneugens exactly and effectively with this method.     

昆明水源水和自来水水质致突变性及化学背景值Ⅱ．蝌蚪红细胞微核和CHO细胞染色体畸变及SCE试验

本文研究的目的是以蝌蚪微核及ＣＨＯ培养细胞染色体畸变（ＣＡ）及姐妹染色单体交换（ＳＣＥ）为指示器,研究昆明市各水厂自来水和它们源水的潜在致突变性。结果表明：①各水厂自来水及它们的源水诱发蝌蚪微核率,除Ｙ－水厂自来水外都有显著性差异。②ＣＡ率的结果：各水厂自来水及源水和对照组除了Ｗ－水厂自来水外,都没有显著性差异。③ＳＣＥ率：高浓度组（０．０６２５Ｌ／ｍｌ）的滇池源水及Ｗ－水厂自来水和低浓度组（０．０３１２５Ｌ／ｍｌ）的Ｗ－水厂自来水同对照组相比,有极显著性差异。低浓度组滇池源水和高浓度组的Ｅ－,Ｓ－水厂自来水有显著性差异。     

人胚细胞提取物抗突变作用的研究

本文应用体外培养人淋巴细胞和小鼠骨髓微核与染色体畸变检测,研究了人胚细胞水提物(胚提物)的遗传毒性和抗突变效应。结果表明,(1)胚提物(3和30μg/ml,下同)可显著抑制培养人淋巴细胞的自发和γ-射线诱发的微核形成;(2)胚提物对培养淋巴细胞的自发染色体畸变无明显影响,但可显著抑制丝裂酶素C(MMC)诱发的染色体畸变; (3)胚提物显著抑制环磷酰胺诱发的小鼠骨髓多染性红细胞微核(PCE-MN)的增加; (4)胚提物的上述抗突变效应呈剂量依赖性增加。因此,作者认为,人胚细胞水提物是一种抗突变剂, 可望用于肿瘤的化学预防,并可用作为肿瘤放疗和化疗的辅助药物,以减少毒付反应和二次肿瘤的发生率。 Abstract:Genetially toxic and antimutagenic effects of the aqueous extracts of human fetal cells(HFCAE) against mutagen-induced chromosomal aberrations and micronucleus formation in human lymphocytes in vitro and bone marrow of mice were studied.HFCAE (3 and 30 μg/ml)significantly inhibited spontaneous and γ-rays-induced micronucleus formation and MMC-induced chromosomal aberrations in human lymphocytes in vitro.HFCAE (3 and 30μg/ml) strongly suppressed also micronucleus formation induced by CP in PCEs of mice.These antimutagenic effects of HFCAE were dose-dependent.Our results suggest that HFCE might be an antimutagen and have potential value in its clinical application.