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121.
Houliston RS Koga M Li J Jarrell HC Richards JC Vitiazeva V Schweda EK Yuki N Gilbert M 《Biochemistry》2007,46(27):8164-8171
The non-typeable Haemophilus influenzae strain DH1 was isolated from a 25 year old male patient with Fisher syndrome, a postinfectious autoimmune condition characterized by the presence of anti-GQ1b IgG antibodies that target and initiate damage to peripheral nerves. DH1 was found to display an alphaNeuAc(2-8)alphaNeuAc(2-3)betaGal branch bound to the tetraheptosyl backbone core of its lipooligosaccharide (LOS). The novel sialylation pattern was found to be dependent on the activity of a bifunctional sialyltransferase, Lic3B, which catalyzes the addition of both the terminal and subterminal sialic acid residues. Patient serum IgGs bind to DH1 LOS, and the reactivity is significantly influenced by the presence of sialylated glycoforms. The display by DH1, of a surface glycan that mimics the terminal trisaccharide portion of disialosyl-containing gangliosides, provides strong evidence for its involvement in the development of Fisher syndrome. 相似文献
122.
123.
Ran Nakashima Yoshitaka Imura Yuji Hosono Minae Seto Akihiro Murakami Kizuku Watanabe Tomohiro Handa Michiaki Mishima Michito Hirakata Tsutomu Takeuchi Keishi Fujio Kazuhiko Yamamoto Hitoshi Kohsaka Yoshinari Takasaki Noriyuki Enomoto Takafumi Suda Kingo Chida Shu Hisata Toshihiro Nukiwa Tsuneyo Mimori 《PloS one》2014,9(1)
124.
Yuh Shiwa Tsuyoshi Hachiya Ryohei Furukawa Hideki Ohmomo Kanako Ono Hisaaki Kudo Jun Hata Atsushi Hozawa Motoki Iwasaki Koichi Matsuda Naoko Minegishi Mamoru Satoh Kozo Tanno Taiki Yamaji Kenji Wakai Jiro Hitomi Yutaka Kiyohara Michiaki Kubo Hideo Tanaka Shoichiro Tsugane Masayuki Yamamoto Kenji Sobue Atsushi Shimizu 《PloS one》2016,11(1)
Differences in DNA collection protocols may be a potential confounder in epigenome-wide association studies (EWAS) using a large number of blood specimens from multiple biobanks and/or cohorts. Here we show that pre-analytical procedures involved in DNA collection can induce systematic bias in the DNA methylation profiles of blood cells that can be adjusted by cell-type composition variables. In Experiment 1, whole blood from 16 volunteers was collected to examine the effect of a 24 h storage period at 4°C on DNA methylation profiles as measured using the Infinium HumanMethylation450 BeadChip array. Our statistical analysis showed that the P-value distribution of more than 450,000 CpG sites was similar to the theoretical distribution (in quantile-quantile plot, λ = 1.03) when comparing two control replicates, which was remarkably deviated from the theoretical distribution (λ = 1.50) when comparing control and storage conditions. We then considered cell-type composition as a possible cause of the observed bias in DNA methylation profiles and found that the bias associated with the cold storage condition was largely decreased (λadjusted = 1.14) by taking into account a cell-type composition variable. As such, we compared four respective sample collection protocols used in large-scale Japanese biobanks or cohorts as well as two control replicates. Systematic biases in DNA methylation profiles were observed between control and three of four protocols without adjustment of cell-type composition (λ = 1.12–1.45) and no remarkable biases were seen after adjusting for cell-type composition in all four protocols (λadjusted = 1.00–1.17). These results revealed important implications for comparing DNA methylation profiles between blood specimens from different sources and may lead to discovery of disease-associated DNA methylation markers and the development of DNA methylation profile-based predictive risk models. 相似文献
125.
Naoya Tanabe Shigeo Muro Shiro Tanaka Susumu Sato Tsuyoshi Oguma Hirofumi Kiyokawa Tamaki Takahashi Daisuke Kinose Yuma Hoshino Takeshi Kubo Emiko Ogawa Toyohiro Hirai Michiaki Mishima 《Respiratory research》2012,13(1):31
Background
The progression of chronic obstructive pulmonary disease (COPD) considerably varies among patients. Those with emphysema identified by quantitative computed tomography (CT) are associated with the rapid progression assessed by forced expiratory volume in one second (FEV1). However, whether the rate of the decline in lung function is independently affected by the regional distribution or the severity of emphysema in the whole lung is unclear.Methods
We followed up 131 male patients with COPD for a median of 3.7 years. We measured wall area percent (WA%) in right apical segmental bronchus, total lung volume, percent low attenuation volume (LAV%), and the standard deviation (SD) of LAV% values from CT images of 10 isovolumetric partitions (SD-LAV) as an index of cranial-caudal emphysema heterogeneity. Annual changes in FEV1 were then determined using a random coefficient model and relative contribution of baseline clinical parameters, pulmonary function, and CT indexes including LAV%, SD-LAV, and WA% to annual changes in FEV1 were examined.Results
The mean (SD) annual change in FEV1 was −44.4 (10.8) mL. Multivariate random coefficient model showed that higher baseline FEV1, higher LAV%, current smoking, and lower SD-LAV independently contributed to an excessive decline in FEV1, whereas ratio of residual volume to total lung capacity, ratio of diffusing capacity to alveolar ventilation, and WA% did not, after adjusting for age, height, weight, and ratio of CT-measured total lung volume to physiologically-measured total lung capacity.Conclusions
A more homogeneous distribution of emphysema contributed to an accelerated decline in FEV1 independently of baseline pulmonary function, whole-lung emphysema severity, and smoking status. In addition to whole-lung analysis of emphysema, CT assessment of the cranial-caudal distribution of emphysema might be useful for predicting rapid, progressive disease and for developing a targeted strategy with which to prevent disease progression. 相似文献126.
Many estimation problems in bioinformatics are formulated as point estimation problems in a high-dimensional discrete space. In general, it is difficult to design reliable estimators for this type of problem, because the number of possible solutions is immense, which leads to an extremely low probability for every solution-even for the one with the highest probability. Therefore, maximum score and maximum likelihood estimators do not work well in this situation although they are widely employed in a number of applications. Maximizing expected accuracy (MEA) estimation, in which accuracy measures of the target problem and the entire distribution of solutions are considered, is a more successful approach. In this review, we provide an extensive discussion of algorithms and software based on MEA. We describe how a number of algorithms used in previous studies can be classified from the viewpoint of MEA. We believe that this review will be useful not only for users wishing to utilize software to solve the estimation problems appearing in this article, but also for developers wishing to design algorithms on the basis of MEA. 相似文献
127.
Yabu T Imamura S Mizusawa N Touhata K Yamashita M 《Marine biotechnology (New York, N.Y.)》2012,14(4):491-501
Autophagy is well established as a starvation-induced process in yeast and mammalian cells and tissues. To elucidate the cellular mechanisms induced by starvation in fish, we characterized the induction of autophagy in cultured zebrafish cells under starvation conditions. As an autophagic marker protein, the microtubule-associated protein 1-light chain 3B protein (MAP1-LC3B) was cloned from the fish cells, and its expression and localization were characterized. In zebrafish embryonic (ZE) cells, posttranslational modifications produced two distinct forms of MAP1-LC3B, i.e., a cytosolic form and a membrane-bound form (types I and II, respectively). Immunofluorescence microscopy revealed fluorescently labeled autophagosomes in cells stably transfected with a green fluorescent protein (GFP)–MAP1-LC3B fusion protein and showed that this protein accumulated in punctate dots in a time-dependent manner in response to amino acid starvation. Starvation also induced the degradation of long-lived proteins. Treatment with 3-methyladenine and wortmannin, two class-III inhibitors of phosphoinositide 3-kinase (PI3K), repressed autophagy under starvation conditions, indicating that the PI3K class-III pathway regulates starvation-induced autophagy in fish. 相似文献
128.
Kensaku Aihara Tomohiro Handa Toru Oga Kizuku Watanabe Kiminobu Tanizawa Kohei Ikezoe Yoshio Taguchi Hiroe Sato Kazuo Chin Sonoko Nagai Shuh Narumiya Athol U. Wells Michiaki Mishima 《PloS one》2013,8(6)
Background
Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease of unknown etiology with few current treatment options. Recently, we determined an important role of prostaglandin F2α (PGF2α) in pulmonary fibrosis by using a bleomycin-induced pulmonary fibrosis model and found an abundance of PGF2α in bronchoalveolar lavage fluid of IPF patients. We investigated the role of PGF2α in human IPF by assessing plasma concentrations of 15-keto-dihydro PGF2α, a stable metabolite of PGF2α.Methods
We measured plasma concentrations of 15-keto-dihydro PGF2α in 91 IPF patients and compared these values with those of controls (n = 25). We further investigated the relationships of plasma 15-keto-dihydro PGF2α concentrations with disease severity and mortality.Results
Plasma concentrations of 15-keto-dihydro PGF2α were significantly higher in IPF patients than controls (p<0.001). Plasma concentrations of this metabolite were significantly correlated with forced expiratory volume in 1 second (Rs [correlation coefficient] = −0.34, p = 0.004), forced vital capacity (Rs = −0.33, p = 0.005), diffusing capacity for carbon monoxide (Rs = −0.36, p = 0.003), the composite physiologic index (Rs = 0.40, p = 0.001), 6-minute walk distance (Rs = −0.24, p = 0.04) and end-exercise oxygen saturation (Rs = −0.25, p = 0.04) when patients with emphysema were excluded. Multivariate analysis using stepwise Cox proportional hazards model showed that a higher composite physiologic index (relative risk = 1.049, p = 0.002) and plasma 15-keto-dihydro PGF2α concentrations (relative risk = 1.005, p = 0.002) were independently associated with an increased risk of mortality.Conclusions
We demonstrated significant associations of plasma concentrations of PGF2α metabolites with disease severity and prognosis, which support a potential pathogenic role for PGF2α in human IPF. 相似文献129.
Mining frequent stem patterns from unaligned RNA sequences 总被引:1,自引:0,他引:1
MOTIVATION: In detection of non-coding RNAs, it is often necessary to identify the secondary structure motifs from a set of putative RNA sequences. Most of the existing algorithms aim to provide the best motif or few good motifs, but biologists often need to inspect all the possible motifs thoroughly. RESULTS: Our method RNAmine employs a graph theoretic representation of RNA sequences and detects all the possible motifs exhaustively using a graph mining algorithm. The motif detection problem boils down to finding frequently appearing patterns in a set of directed and labeled graphs. In the tasks of common secondary structure prediction and local motif detection from long sequences, our method performed favorably both in accuracy and in efficiency with the state-of-the-art methods such as CMFinder. AVAILABILITY: The software is available upon request. 相似文献
130.
Takahisa Yamanouchi Kayoko Domae Osamu Tanishita Yoshiyuki Takahashi Koichi Yamanishi Michiaki Takahashi Takeshi Kurata 《Microbiology and immunology》1984,28(12):1345-1353
Newborn mice and rats were inoculated intracerebrally (ic) or intraperitoneally (ip) with Hantaan virus (76–118 strain) or HFRS-related virus (B-1 strain). The mortality and the influence on the increase of body weight in newborn mice were higher in the groups infected with the 76–118 strain than in the groups infected with the B-1 strain, while the B-1 strain was more virulent in rats than the 76–118 strain. Virus isolation from rats inoculated with either strain was attempted 7 and 11 weeks after inoculation. Virus could be isolated from various organs of rats infected with the B-1 strain, while it was recovered from only the brain and lungs of rats infected with the 76–118 strain. Viral antigen was readily detected in various organs of rats infected with the B-1 strain, but the amount and distribution of antigens were less in rats infected with the 76–118 strain. Our results suggest that the virulence of HFRS-related virus is variable, depending on the species of infected animals as well as on the. virus strains. The virus also persists in the injected animals with high titers of antibodies for at least 11 weeks. 相似文献