乳腺囊性增生病癌变过程中部分因素变化的意义

检测乳腺囊性增生病（ＦＣＤ）经不典型增生到癌变部分因素的变化。结果提示：从因明显ＦＣＤ症状活检至癌变为２～１０年；从Ⅱ级以上不典型增生到临床癌变需２～７年；癌变率为３．１％。ＦＣＤ患者存在性激素分泌调控失常，血浆雌激素和催乳素含量增加，导致上皮细胞增生。乳腺一般性增生细胞的ＤＮＡ含量和超微结构与正常乳腺上皮细胞相似；无肿瘤相关抗原及异常基因产物表达。而发生在一般性增生基础上的不典型增生则呈现细胞基因物质ＤＮＡ含量增加，部分为超４Ｃ的多倍体细胞；同时出现细胞膜和细胞核超微结构异常；雌激素受体含量增加，对性激素的依赖性和敏感性增强；部分不典型增生细胞出现胚胎性肿瘤相关抗原和异常基因产物表达。随不典型增生程度加重至乳腺癌，上述诸因素的变化趋势具有明显规律性。提示ＦＣＤ上皮细胞从一般性增生经不典型增生至乳腺癌为细胞生物学连续逐渐变化的过程。部分不典型增生细胞中具有癌倾向的细胞生物学行为异常和表型变化与乳腺癌发生密切相关。细胞核ＤＮＡ含量等异常变化及程度可作为乳腺癌前病变发展程度的客观标志     

精神分裂症患者外周血淋巴细胞姊妹染色单体交换的初步观察

检测了18例精神分裂症患者和25例健康人的SCE频率,结果提示患者组SCE频率显著高于对照组,与年龄、性别、病程、临床类型、有无遗传家族史无明显相关。研究提示SCE频率增高似与疾病本身有关。     

DNA探针的高效标记和哺乳动物细胞转化子的检测

本实验采用随机引物法标记探针DNA.探针DNA加热变性成单链,以单链DNA为模板,六聚脱氧核苷酸为引物,在DNA多聚酶I大片段的作用下进行放射性标记.标记探针的比放射性达10~8cpm/μg DNA以上.放射性底物的掺入率为60%.用该方法标记的人高度重复顺序探针,可以检出微微克水平的阳性分子.与人HeLa S_3细胞DNA转化的小鼠LTK~+细胞DNA打点杂交呈阳性,与未经转化的小鼠LTK~-细胞DNA杂交为阴性,证明小鼠转化细胞中存在HeLa细胞DNA,DNA转化是成功的.     

测定血液脱氧核糖核酸方法的探讨

本文探讨６种测定ＤＮＡ的方法。以吲哚反应一醋酸异成酯抽提的方法最好，比较稳定而灵敏，一般实验室条件就可进行，测定仅需０．１ｍｌ血液。     

The <Emphasis Type="Italic">Arg</Emphasis>194<Emphasis Type="Italic">Trp</Emphasis> polymorphism in DNA repair gene XRCC1 and the risk for sporadic late-onset Alzheimer's disease

Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.     

Polymorphic distribution of Y-chromosome haplotype and mitochondrial DNA in the Bouyei people in China

In the evolution of humans, many kinds of mutations in the human genome have been accumulated, providing credible genetic evidence for the study of human origins and migrations. The "out-of-Africa" hypothesis of modern human evolution and the genetic origin of the Japanese has come about by studying mitochondrial DNA.l,2 Recently, researchers have recognized the power of Y-chromosome markers in resolving migratory patterns of modern humans as more and more Y-chromosome single nucleotide polymorphism markers have been found. The markers on the nonrecombinant part of the Y-chromosome allows for the reconstruction of intact haplotypes which are probably the best genetic tools to study human migrations. We can analyze the paternal history of some people in different areas by Y-chromosome haplotypes.     

单细胞凝胶电泳技术在生殖细胞DNA损伤检测中的应用

单细胞凝胶电泳技术(SCGE)是一种快速检测单个细胞DNA损伤的实验技术,在生殖细胞DNA损伤的检测中广泛应用。本综述系统介绍了SCGE在睾丸生精细胞、支持细胞、间质细胞、卵巢细胞以及卵母细胞等生殖细胞DNA损伤检测中的应用现状,并对SCGE在生殖毒性检测中的发展提出了展望。     

Observations on two members of the Swedish family with congenital dyserythropoietic anaemia,type III

Abstract: Two affected individuals of the Swedish family with CDA, type III, in which the disease is transmitted as an autosomal dominant character, were studied. Both cases displayed features hitherto undescribed in this family but described in patients with CDA, type III, in whom the inheritance may have been as an autosomal recessive character. Such features were: (a) haemosiderinuria, (b) grossly disorganised erythroblast nuclei, (c) differences in the ultrastructural appearances of individual nuclei within the same multinucleate erythroblast and (d) intraerythroblastic inclusions resembling precipitated globin chains. In both cases the giant mononucleate erythroblasts and the multinucleate erythroblasts had total DNA contents up to 28c (1c = haploid DNA content) and 48c respectively, and some DNA synthesising bi- and multinucleate erythroblasts contained one or more nuclei which were unlabelled with ³H-thymidine. These findings are similar to those in patients with the autosomal recessive type of disease. Thus no major phenotypic differences are yet apparent between cases of CDA, type III, with different patterns of inheritance. Analysis of the surface erythrocyte proteins of the 2 Swedish CDA, type III, patients with monoclonal antibodies recognising Band 3, glycophorins A, B, C and D, Rh, CD44, CD47, CD55, CD58, CD59, Lutheran, Kell, LW and acetylcholinesterase did not reveal any gross abnormality of expression of these proteins. A slightly altered expression of blood group antigens A and H was revealed by the lectins Dolichos biflorus and Ulex europaeus and the Mr of Band 3 as judged by SDS polyacrylamide gel electrophoresis was also slightly reduced, suggesting that there may be minor alterations in the degree of N-glycosylation of some red cell membrane constituents.