Molecular genetics of phenylketonuria in Orientals: linkage disequilibrium between a termination mutation and haplotype 4 of the phenylalanine hydroxylase gene.

Phenylketonuria (PKU) is a common metabolic disorder among Chinese, with a prevalence of about 1 in 16,500 births. This frequency is very similar to that among Caucasians. Individual exons of the phenylalanine hydroxylase (PAH) gene with flanking introns were amplified by polymerase chain reaction and cloned into M13 for sequence analysis. An Arg111-to-Ter111 mutation has been identified in exon 3 of the PAH gene in a Chinese PKU patient. The mutation is in linkage disequilibrium with the mutant haplotype 4 alleles which are the most prevalent haplotype among the Orientals. The mutation accounts for about 10% of the Chinese PKU alleles and is absent from the Caucasians, demonstrating that independent mutational events have occurred in the PAH locus after racial divergence.     

Microtubule and microfilament distribution and tubulin content in the cell cycle of Indian muntjac cells

Using DAPI, rabbit antitubulin antibody, FITC-labeled goat anti-rabbit IgG, and TRITC-phalloidin to stain individual cells, the microspectrophotometric analysis showed that three markers that represent the nucleus, microtubules (MT), and microfilaments (MF), respectively, could be recognized in individual cells without interference. The phase of the cell cycle was determined by DNA content. We found that in Indian muntjac (IM) cells, the amount of tubulin in G2 and M phases was about twice as much as that in G1 phase. In G2 cells, the cytoplasmic microtubule complex (CMTC) became denser than in G1 cells. The cytoplasmic MT extent in basically the same orientation as MF bundles in interphase. The regions where the MT is denser also have a denser MF distribution.     

用合成的寡核苷酸探针鉴定中国人β-地中海贫血基因突变

用人工合成的六种对β-地中海贫血基因特异的寡核苷酸作为杂交探针,对10例β-地中海贫血病人及其父母的β-珠蛋白基因进行分析,鉴定出六种β-地中海贫血突变:(1)TATA Box-28 A→G;(2)IVS-1n.5 G→C;(3)Codon 17 A→T;(4)codons 41—42—46p;(5)Codons 71—72+A;(6)IVS-2 n.654C→T。本文分析的中国人β-地中海贫血患者中,上述六种突变所占的百分比分别为5％,10％,10％,40％,20％和15％。     

异细胞质八倍体小黑麦的获得及其细胞遗传

改变小黑麦细胞质有可能增加减数分裂的稳定性,提高小黑麦的结实率与籽粒饱满度。作者以不同细胞质的“中国春”小麦与黑麦杂交,F_1幼苗用秋水仙素加倍获得双二倍体、或以八倍体小黑麦为父本与F_1杂交,获得异细胞质八倍体小黑麦(Triticale 8x)8个品系。实验结果表明:细胞质不同的“中国春”小麦与黑麦杂交结实率差异显著,出苗率亦不同,F_1株型多为两亲的中间型,花药不开裂,个别组合出现雄蕊雌化现象,有的组合表现生长弱性,减数分裂中期Ⅰ常出现1至数个末端交叉的棒状二价体,其数量在不同组合间差异显著,表明异细胞质对染色体配对有影响。D类细胞质对改进八倍体小黑麦的结实率可能有一定的作用。     

1,4—二取代酰氨基硫脲化合物A导致黄瓜增产的生理基础的初步研究

用0.1ppm的1—异烟酰—4-(4′-氯代苯基)—氨基硫脲(以下用A代表)喷施3—4叶期的黄瓜(Cucumis sativus L.)幼苗,可以提高叶片光合速率并导致黄瓜增产。进一步的实验结果表明:经0.1ppm A处理后,黄瓜叶片的叶绿素含量(a+b)增加约50%,叶绿素a/b比值降低约30%,叶黄素含量增加近2倍,光合磷酸化活性增强。这些变化可能是黄瓜增产的生理基础。     

应用蛋白印迹法检测鼻咽癌病人血清中抗Epstein—Barr病毒IgA/EA抗体

曾毅等建立了一系列检测EB病毒IgA/VCA和IgA/EA抗体的鼻咽癌早期诊断方法,取得了满意的结果。为了进一步提高对鼻咽癌诊断更为特异的IgA/EA抗体的检出率,我们建立了检测EB病毒IgA/EA抗体的蛋白印迹法。方法敏感特异,结果令人满意。 本法中所用的两个质粒系由本实验室与西德Pettenkofer研究所Wolf教授的实验室合作构建。pUCARG1140和pUC9MBcE3.2质粒均为表达质粒,前者携带着来源于EB病毒Bam     

应用明胶颗粒凝集试验检测人免疫缺陷病病毒(HIV-1)抗体

明胶颗粒凝集试验是测定HIV-1抗体的新方法。本研究将明胶颗粒凝集试验与ELISA法、蛋白印迹法和间接免疫荧光试验做了比较,观察本方法的敏感性和特异性。共检测了195份来自法国和非洲象牙海岸的血清,凡是蛋白印迹法阳性的血清,明胶颗粒凝试验都是阳性。这表明本方法是特异和敏感的,方法简便,不需特殊仪器,省时,可用于HIV-1抗体的筛选,但多数蛋白印迹法可疑的血清,明胶颗粒试验均阴性。因此,对蛋白印迹法测出的可疑者应该用数种方法进行追踪检测。     

一种高生产力和生态协调的亚热带针阔混交林——杉木火力楠混交林的研究

 通过八年杉木针阔混交林的综合定位研究,筛选出一种高生产力和生态协调的人工林一以8杉木2火力楠为优势的混交林。林分的蓄积量和乔木层贮存的能量分别比杉木纯林高13.7%和11.3%,杉木火力楠混交林提高了林分的光能利用率,改善了林内小气候;增加了林地有机质的含量;促进了土壤中有益微生物的繁衍和土壤理化性质的改良,提高了土壤肥力和蓄水保水能力;增强了林分对害虫自我抑制能力。     

DNA拓扑异构酶Ⅰ生物学活性的比较研究

测定了3T3细胞、人和大鼠一些组织中DNA拓扑异构酶Ⅰ的活性;估计了核酸内切酶对拓扑酶Ⅰ松弛活性测定的干扰程度;发现增殖组织全细胞抽提液中酶比活高于正常分化组织,而且在异常增殖组织中酶比活的增高更为显著。