Periodicity of SNP distribution around transcription start sites

BACKGROUND: Several millions single nucleotide polymorphisms (SNPs) have already been collected and deposited in public databases and these are important resources not only for use as markers to identify disease-associated genes, but also to understand the mechanisms that underlie the genome diversification. RESULTS: A spectrum analysis of SNP density distribution in the genomic regions around transcription start sites (TSSs) revealed a remarkable periodicity of 146 nucleotides. This periodicity was observed in the regions that were associated with CpG islands (CGIs), but not in the regions without CpG islands (nonCGIs). An analysis of the sequence divergence of the same genomic regions between humans and chimpanzees also revealed a similar periodical pattern in CGI. The occurrences of any mono- or di-nucleotide sequences in these regions did not reveal such a periodicity, thus indicating that an interpretation of this periodicity solely based on the sequence-dependent susceptibility to mutation is highly unlikely. CONCLUSION: The periodical patterns of nucleotide variability suggest the location of nucleosomes that are phased at TSS, and can be viewed as the genetic footprint of the chromatin state that has been maintained throughout mammalian evolutionary history. The results suggest the possible involvement of the nucleosome structure in the promoter function, and also a fundamental functional/structural difference between the two promoter classes, i.e., those with and without CGIs

Simultaneous Polymerization by Cationic and Anionic Catalysts

In our previous paper simultaneous cationic and anionic polymerizations have been reported to proceed in the case of the graft copolymerization of β-propiolactone with Nvinyl carbazole onto the trunk polymers containing -SO₃ Na or -COOH groups. In this paper, the simultaneous polymerization by cationic and anionic catalysts was carried out in a liquid system for homopolymerization. The cationic and anionic polymerizations were recognized to occur simultaneously at the comparative rates of both cationic and anionic polymerizations, at least in the case having one of the following conditions at ; (i) relatively heterogeneous system. (ii) the reaction medium having high dielectric constant, or (iii) relatively stable growing anionic and cationic ends

A Model For Design Auto Instrumentation To Appeal To Young Male Customers

This paper applies statistical science to create a model for auto instrumentation, an aspect of vehicle design that has a powerful effect on young male customers. The authors develop an instrumentation design that will appeal to the target users to verify the effectiveness of an Auto Instrumentation Designing Approach Model

ESR Study of Radiation-induced Solid State Polymerization of Conjugated Dienes

ESR spectra of free radicals formed from isoprene, 1, 3-pentadiene and 2, 3-dimethyl-l, 3-butadiene were studied at -196°C. Free radicals were formed by several ways, i.e. electron-irradiation, reaction with HO· and CH₃· radicals and ultraviolet-irradiation at -196°C. The structure of trapped free radicals formed by electron-irradiation are quite different from that of radicals formed by radical reactions. The mechanism of radiation-induced solid state polymerization is discussed. It is concluded that the trapped free radical formed by radiation is not the propagating radical but an inactive radical end which is formed in the ionic propagation process initiated by an ion-radical

Electron Spin Resonance Study on Irradiated Styrene in Crystalline and Glassy States

Styrene was irradiated at-196°C to give a five-line spectrum with a coupling constant of about 16 gauss. This is attributed to the free radical When a mixture of styrene and 2-methyltetrahydrofuran was irradiated, a broad singlet spectrum (total width 33 gauss) was superposed on the seven-line spectrum due to the methyltetrahydrofuran radical and no sharp singlet spectrum due to trapped electrons was observed. This broad singlet spectrum is thought to be due to styrene anion radicals. This spectrum was bleached by visible light and saturated appreciably with increasing microwave power. Similar phenomena were observed for a styrene-3-methylpentane mixture

Factors Affecting Catecholamines in Caregivers of Patients with Dementia

Background: Caregivers of dementia patients have significantly higher levels of serum IL-6 and CRP compared to non-caregivers, and the accumulation of everyday stressors reportedly promotes the induction of inflammatory markers. However, few studies have identified factors that affect catecholamine levels in caregivers who experience a combination of physical and mental stress from caregiving. Purpose: This study aimed to identify physical factors that impact catecholamine levels in caregivers of dementia patients. Methods: Participants were elderly caregivers living together with elderly Alzheimer’s-type dementia patients. We performed logistic regression analysis, with levels of adrenaline, noradrenaline, and dopamine (indicators of catecholamine) as dependent variables. Results: Caregiver BMI had a significant impact on adrenaline levels (OR: 0.792; 95%CI: 0.654-0.960) and noradrenaline levels (OR: 1.210; 95%CI: 1.009-1.451), whereas age had a significant impact on dopamine levels (OR: 1.162; 95%CI: 1.019- 1.324). Discussion: While caregiver BMI significantly impacted adrenaline and noradrenaline levels, the mechanism underlying these relationships is unclear. One possibility is that obesity (BMI) and a rise in sympathetic nerve activity contributed to hypertension. Our findings suggest that chronic stress in elderly caregivers may potentially impair the dopaminergic activation system in the brain. Conclusion: There is a need to identify factors which increase BMI in caregivers. Future studies aimed at gaining a better understanding of the lifestyle habits of caregivers and intervention studies aimed at reducing their BMI are warrante

Guided Wave Focusing Mechanics in Pipe

Guided waves can be used in pipe inspection over long distances. Presented in this paper is a beam focusing technique to improve the S∕N ratio of the reflection from a tiny defect. Focusing is accomplished by using nonaxisymmetric waveforms and subsequent time delayed superposition at a specific point in a pipe. A semianalytical finite element method is used to present wave structure in the pipe. Focusing potential is also studied with various modes and frequencies

沿岸海域における細菌群の分布と増殖速度(自然科学)

愛知県三河湾の干潟域を主要な研究対象水域とした。海水および干潟砂泥中に存在する細菌群の現存量と増殖速度などを測定し,沿岸海域における細菌群の生態,作用などを明らかにすることを目的として研究した。1)三河湾の干潟域に設定した9定点の試料について測定した細菌群の現存量は,年間を通じて少数の例外を除いて著しい差が認められなかった。2)干潟域海水中には,5.5×10^6cells/ml,砂粒子中には5.0×10^8cells/g(wet)程度の総菌数であった。3)海水中における細菌群の増殖速度は,除菌により細菌数を少数とする程増大した。4)自然海水中では,繊毛虫や鞭毛虫などにより,多数の細菌群が捕食されているが,捕食された量は細菌群の絶えざる増殖によって補給されているので,海水中には一定レベルの細菌数が維持されている。5)河川水中の細菌群は,沿岸海水中に流入してもすべて死滅することはなく,10^3～10^4cells/ml程度の細菌は海水環境においても増殖可能であった。また海水中に存在する10^3～10^4cells/mlの細菌は,淡水中においても増殖可能であった。6)三河湾干潟域海水中では,Vibrio, Pseudomonas, Bacillus, Micrococcusなどが主要な菌株であり,干潟砂中には,Vibrio, Pseudomonas, Bacillusが主要な菌株であった。干潟砂の10cm下層では,Clostridium, Bacillus, Bacteroidesなどに属する菌株が主要なもので,これらは,嫌気条件下において増殖できる分離菌株の約80%であった。7)干潟域海水中には,10cells/ml,干潟砂中には10^2cells/g(wet)程度の酵母が分布していた。干潟砂から分離した酵母は,Rhodotorula約45%,Torulopsis 43%, candida 10%であった。沿岸海域において,これら酵母の作用は微弱であると推定される

Evaluation of Haplotype Inference Using Definitive Haplotype Data Obtained from Complete Hydatidiform Moles, and Its Significance for the Analyses of Positively Selected Regions

The haplotype map constructed by the HapMap Project is a valuable resource in the genetic studies of disease genes, population structure, and evolution. In the Project, Caucasian and African haplotypes are fairly accurately inferred, based mainly on the rules of Mendelian inheritance using the genotypes of trios. However, the Asian haplotypes are inferred from the genotypes of unrelated individuals based on population genetics, and are less accurate. Thus, the effects of this inaccuracy on downstream analyses needs to be assessed. We determined true Japanese haplotypes by genotyping 100 complete hydatidiform moles (CHM), each carrying a genome derived from a single sperm, using Affymetrix 500 K Arrays. We then assessed how inferred haplotypes can differ from true haplotypes, by phasing pseudo-individualized true haplotypes using the programs PHASE, fastPHASE, and Beagle. We found that, at various genomic regions, especially the MHC locus, the expansion of extended haplotype homozygosity (EHH), which is a measure of positive selection, is obscured when inferred Asian haplotype data is used to detect the expansion. We then mapped the genome using a new statistic, XDiHH, which directly detects the difference between the true and inferred haplotypes, in the determination of EHH expansion. We also show that the true haplotype data presented here is useful to assess and improve the accuracy of phasing of Asian genotypes