Isolation and regional localization of a large collection (2,000) of single-copy DNA fragments on human chromosome 3 for mapping and cloning tumor suppressor genes

Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies.     

糙叶败酱挥发油镇静作用的研究

本文观察了败酱科植物糙叶败酱(Patrinia scabra Bunge)根和根茎中制得的挥发油的镇静作用,井与黄花败酱挥发油做了比较。结果表明,此油灌胃给予数组小鼠,剂量0.45ml/kg,显示如下的作用:[1]能显著延长由于腹腔注射戊巴比妥钠(50mg/kg)引起的小鼠睡眠时间,但其作用强度弱于黄花败酱挥发油。(2)一次灌胃给予小鼠大剂量10.46g/kg的糙叶败酱挥发油,连续观察10天,动物外观正常,无一死亡,体重增加与对照组相似。     

Multiple origins for phenylketonuria in Europe

Phenylketonuria (PKU), a disorder of amino acid metabolism prevalent among Caucasians and other ethnic groups, is caused primarily by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). PKU is a highly heterogeneous disorder, with more than 60 molecular lesions identified in the PAH gene. The haplotype associations, relative frequencies, and distributions of five prevalent PAH mutations (R158Q, R261Q, IVS10nt546, R408W, and IVS12n1) were established in a comprehensive European sample population and subsequently were examined to determine the potential roles of several genetic mechanisms in explaining the present distribution of the major PKU alleles. Each of these five mutations was strongly associated with only one of the more than 70 chromosomal haplotypes defined by eight RFLPs in or near the PAH gene. These findings suggest that each of these mutations arose through a single founding event that occurred within time periods ranging from several hundred to several thousand years ago. From the significant differences observed in the relative frequencies and distributions of these five alleles throughout Europe, four of these putative founding events could be localized to specific ethnic subgroups. Together, these data suggest that there were multiple, geographically and ethnically distinct origins for PKU within the European population.     

Association of a polymorphism of the angiotensin I-converting enzyme gene with essential hypertension.

Angiotensin I-converting enzyme (ACE) is responsible for production of angiotensin II and breakdown of kinins, leading to increased blood pressure (BP). Furthermore, ACE inhibitors are effective antihypertensive agents. A 287 bp insertion/deletion polymorphism in intron 16 of the ACE gene (ACE) was examined by PCR in a cross-sectional study of 80 hypertensive (HT) and 93 normotensive (NT) subjects whose parents had a similar BP status at age greater than or equal to 50. The frequency of the insertion allele was 0.56 in HTs and 0.41 in NTs, and the difference between observed alleles in all subjects in each group was significant (chi 2 = 7.6, P less than 0.01). The data thus provide evidence in favour of an association of HT with a polymorphism at the ACE locus (17q23), so implicating this locus, and possibly a genetic variant of ACE itself, in human essential hypertension.     

孕产妇生殖道单纯疱疹病毒感染垂直污染羊水的研究

用ＤＮＡ聚合酶链反应检测单纯疱疹病毒特异性核酸,调查１００名孕产妇生殖器官脂ＨＳＶ感染和羊水受ＨＳＶ污染的情况,结果表明：受感染的母体通过病毒护散途径及通过产道途径,污染羊水的机率分别为１１．１％和５４．５％;原发性ＨＳＶ、继发性ＨＳＶ垂直污染羊水机率分别为６６．７％和２９．４％;不同妊娠期和生育胎次对污染率无显著性影响。     

高邮杂交鲫（鲫♀×白鲫）及其亲本血清生化组成的比较研究

本文对高邮杂交鲫（鲫♀×白鲫♂）及其亲本血清生化组成的定量分析。结果表明,在测定的血清总蛋白、白蛋白、胆固醇、尿素氮、葡萄糖、乳酸脱氢酶、ａ－羟丁酸脱氢酶、ａ－淀粉酶和谷草转氨酶等九个生化指标中,大部分指标高邮杂交鲫与母本无显著差异,而与父本则有极显著差异。这从代谢方面论证了高邮杂交鲫是一个偏向于母本的杂交种。     

Atypical metachromatic leukodystrophy?

Summary A 3/12-year-old slightly retarded boy with marked deficiency of arylsulfatase A (ASA) activity in leucocytes and fibroblasts and almost no cerebroside sulfatase (CS) activity in fibroblasts was tested with the sulfatide-loading test. On this test his fibroblasts showed impaired degradation. A pathological excretion of sulfatides was seen in his urine. Nerve conduction velocity, visual evoked potential, auditory brain stem evoked response, and somatosensory evoked potential were all normal.His father and older brother had similarly low levels of ASA in leucocytes and fibroblasts and 1.7–2% residual CS activity in fibroblasts. Although both were clinically normal, their fibroblasts accumulated increased amounts of sulfatides when challenged in the sulfatide-loading test.In this family, this test thus will be of no value in prenatal diagnosis to discriminate among low ASA fetuses with pseudoarylsulfatase A deficiency and fetuses with this unusual ASA deficiency variant.     

Cyclin B in fish oocytes: its cDNA and amino acid sequences, appearance during maturation, and induction of p34cdc2 activation.

Under the influence of maturation-inducing hormone (MIH) secreted from follicle cells, oocyte maturation is finally triggered by maturation-promoting factor (MPF), which consists of a homolog of the cdc2+ gene product of fission yeast (p34cdc2) and cyclin B. Two species of cyclin B clones were isolated from a cDNA library constructed from mature goldfish oocytes. Sequence comparisons revealed that these two clones are highly homologous (95%) and were found to be similar to Xenopus cyclin B1. Using monoclonal antibodies against Escherichia coli-produced goldfish cyclin B and the PSTAIR sequence of p34cdc2, we examined the levels of cyclin B and p34cdc2 proteins during goldfish oocyte maturation induced in vitro by 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (17 alpha, 20 beta-DP), a natural MIH in fish. Protein p34cdc2 was found in immature oocyte extracts and did not remarkably change during oocyte maturation. Cyclin B was not detected in immature oocyte extracts and appeared when oocytes underwent germinal vesicle breakdown. Cyclin B that appeared during oocyte maturation was labelled with [35S]methionine, indicating its de novo synthesis. Introduction of E. coli-produced cyclin B into immature oocyte extracts induced p34cdc2 (MPF) activation. Although the possibility that immature goldfish oocytes contain an insoluble cyclin B is not completely excluded, these results strongly suggest that 17 alpha, 20 beta-DP induces oocytes to synthesize cyclin B, which in turn activates preexisting p34cdc2, forming active MPF.