肝豆状核变性RFLP连锁分析的建立及症状前诊断和杂合子检出的研究

ＲＢ１基因位于ＤＩ３ｑ１４－２１，与Ｗｉｌｓｏｎ氏病基因紧密连锁，遗传距离为４．４ｃｍ（ｃｅｎｔｉｍｏｒｇａｎ），其３＇端第１７号内含子中ｐ６８ＲＳ２．０标记的等位片段与白种人相同，但基因频率存在差异，杂合子频率为４３％。应用该标记对１１个ＷＤ家系进行ＲＦＬＰ连锁分析，检出３名症状前患者，１１名杂合子及３名正常纯合子，证实ｐ６８ＲＳ２．０标记可用于Ｗｉｌｓｏｎ氏病的症状前诊断及杂合子筛选。     

中国人血管抑素基因的克隆及其序列分析

目的：克隆中国人血管抑素(angiostatin，ANG)基因全长并进行序列分析。方法：应用RT-PCR，将5例健康人肝脏组织ANG基因克隆到pSP71载体上，用Sanger法进行基因测序分析。结果：通过RT-PCR获得一个1141bp的扩增产物，测序发现与已报道的ANG比较，国人ANG上有3个碱基突变位点：分别为第825位C→T；第927位T→G和第1078位G→A。前两个碱基突变氨基酸未发生变化，第3个碱基突变结果使缬氨酸(Val342)改变成为蛋氨酸(Met342)。结论：克隆得到中国人ANG基因片段，其碱基和氨基酸的变化可能是人群中该基因的遗传多态现象。     

蜗牛卵液对小鼠S_(180)肉瘤的抑制作用

[目的 ]探讨蜗牛卵液对小鼠S180 肉瘤的抑制作用 .[方法 ]按标准方法给 4 0只小鼠接种S180肉瘤细胞后 ,随机分成 4个组 ,即对照组 :每日灌胃生理盐水 10mL/kg ;实验 1组 :每日灌胃蜗牛卵液1 5 g/kg ;实验 2组 :每日灌胃蜗牛卵液 3 0 g/kg ;实验 3组 :每日灌胃蜗牛卵液 3 8g/kg ;连续 8d后 ,观察肿瘤质量变化及胸腺 (脾脏 )指数 .[结果 ]每日 1 5 ,3 0 ,3 8g/kg的蜗牛卵液对小鼠S180 肉瘤的生长抑制率分别为 38 2 % ,4 0 5 % ,5 4 4 % ,实验 3组的肿瘤抑制率高于对照组 ,两组间有显著性差异 ;实验2组和实验 3组的胸腺 (脾脏 )指数低于对照组 ,与对照组相比较亦有显著性差异 .[结论 ]蜗牛卵液对小鼠S180 肉瘤有抑制作用 .     

Light microscopy of GTP-binding protein (Go) immunoreactivity within the retina of different vertebrates

To examine species differences in the distribution pattern of guanosine triphosphate (GTP)-binding protein (Go) within the vertebrate retina, paraffin-embedded retinae from a number of vertebrate species, including the goldfish, frog, turtle, chicken, monkey, and human, were immunohistochemically stained with affinity-purified antibody against the alpha-subunit of Go. Go-immunoreactive products were found to be located in the neuropil, but not in the cell bodies of neurons, in the retina of all these species. However, some species differences were observed. In the frog, monkey and human, the inner plexiform layer (IPL) was homogeneously stained with this antibody, but in the goldfish, turtle and chicken, the IPL was heterogeneously stained. In the frog, chicken, turtle and human, the outer plexiform layer (OPL) was densely stained with this antibody, but in the goldfish and monkey, the OPL was rather faintly immunoreactive to the antibody. In the goldfish, monkey and human, the outer nuclear layer (ONL) was not immunoreactive to the Go-antibody, whereas in the frog, turtle and chicken, the ONL was immunoreactive to it. The implications of these species differences in Go localization in the vertebrate retina are discussed.     

东方人苯丙酮尿症的分子遗传学—苯丙氨酸羟化酶基因中一终止突变与单体型4的连锁不平衡性

应用聚合酶链反应(PCR)方法扩增苯丙氨酸羟化酶(PAH)基因的每个外显子及其侧翼的内含子,并克隆到M 13载体中进行序列分析。发现中国人苯丙酮尿症(Phenylketonuria,PKU)患者的PAH基因外显子3中有1个Arg~(111)→Ter~(111)的点突变,此突变与东方人最常见的突变单体型4呈连锁不平衡。此突变占中国人PAH等位基因的10％左右,但不存在于高加索人群中,表明在种族分化过程中PAH基因位点发生了互不相关的突变事件。     

''Gender gap'' in multiple sclerosis: magnetic resonance imaging evidence

The authors evaluated the gender difference in the magnetic resonance imaging characteristics of the lesions occurring in the brain of 413 multiple sclerosis (MS) patients. Men had fewer contrast-enhancing lesions (P = 0.01), but a higher proportion of lesions evolving into 'black holes' (P = 0.001), when compared with women. Thus, our data indicate that men with MS are prone to develop less inflammatory, but more destructive lesions than women. This study results provides support for a modulation of the MS pathological changes by gender.     

Multistep phase difference phase contrast imaging

A new technique for multistep phase-contrast image processing is presented. The N-step method consists of simply forming the linear average of the N — 1 adjacent phase-difference signals. It has similar noise reduction properties as other multistep techniques, but the simplicity of the noise variance of the N-step technique allows intuitive insight into phase-difference phase-contrast processing and noise reduction, which can aid in the design of efficient and improved phase-contrast imaging sequences. As well, the computational simplicity of the N-step phase-difference technique compared with any other known multistep technique is advantageous. Like other multistep techniques, it has far more efficient noise reduction properties than simple two-step, multiple average phase-contrast imaging, even when normalized for total scan time. A three-step phase-difference velocity image has 50% less variance than an image acquired with two steps and two scans averaged but is obtained in 25% less scan time. Given its advantages, it should now be the chosen technique for increasing velocity-to-noise and contrast-to-noise ratios in all phase-difference phase-contrast clinical applications.     

Large French-Canadian family with Lewy body parkinsonism: exclusion of known loci.

The identification of rare, large families with Parkinson's disease (PD) has provided important clues that have contributed to our understanding of this complex disorder. We have identified a large French-Canadian kindred that spans five generations consisting of more than 90 individuals. A total of 65 individuals now have been examined, had venous blood drawn, and DNA extracted. Two-point and multipoint linkage analysis was performed to assess linkage to known PD genes or loci. Within the third and fourth generations of this family there are 10 living, plus 3 deceased members with well-documented levodopa responsive parkinsonism. Autopsy results on 1 member demonstrated the loss of pigmented neurons in the substantia nigra and the presence of alpha-synuclein positive Lewy bodies. Four of the PD patients have prominent postural and kinetic tremors that preceded their parkinsonism by up to 10 years. Two other individuals within the family have prominent isolated postural and kinetic tremors without parkinsonism. The alpha-synuclein(4q21.3-23), Parkin(6q25.2-27), PARK3 (2p13), PARK4, and ubiquitin carboxy terminal hydrolase-L1 (4p14-16.3) and PARK6 and PARK7 (1p35-36) loci were excluded in this kindred using closely linked markers. The clinical and pathological features of this family are consistent with the diagnosis of PD. This family further demonstrates the known genetic heterogeneity in PD and is large enough that a genome-wide screen has been undertaken in an effort to identify a novel PD gene.     

Breast Cancer Genes

Abstract: The identification of familial breast cancer genes heralds an era of directed breast cancer treatment. Currently, two hereditary breast cancer genes have been identified, BRCA-1 and BRCA-2 . Although accounting for only approximately 5% of all breast cancers, they are being used to identify women with germ-line alterations that are at high risk of developing breast or ovarian cancer. With the identification of such genes comes a need for consideration of the ethical issues associated with testing. These genes are also being examined from a biochemical standpoint encompassing both their biological roles and biochemical pathways in which they reside. Such studies are likely to lead to novel breast cancer therapies.     

福建莆田739例遗传咨询者细胞遗传学分析

目的 :探讨福建莆田遗传咨询者的医学细胞遗传学主要特征。方法 :采用细胞遗传学方法对 739例遗传咨询者进行外周血淋巴细胞检查。结果 :739例遗传咨询者中发现染色体异常 5 6例 ,异常率为 7.5 8% ,其中常染色体数目结构异常 4 3例 ,占 76 .9% ,性染色体异常 13例 ,占 2 3.1%。结论 :智力低下、不良孕产史、性发育异常与遗传染色体异常密切相关 ,不良孕产史推出异常核型率 3.31% ,较正常群体的 0 .5 %显著性增高 ,与文献报道基本符合