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31.
Noriko Kato Sachiko Karaki Kouichi Kashiwase Claudia Müller Tatsuya Akaza Takeo Juji Kyoichi Kano Masafumi Takiguchi 《Immunogenetics》1993,37(3):212-216
Serological studies have suggested the presence of a new HLA-B39 subtype (B39.2) in the Japanese population. To identify the new HLA-B39 subtype and compare it with an other HLA-B39 subtype (B39.1), the genes encoding HLA-B39.1 (B
*
39013) and B39.2 (B
*
3902) have been cloned from Japanese. We have sequenced these genes and completed the sequence of HLA-B39.1 (B
*39011
) gene from a Caucasian that was partially sequenced. Comparison of the sequence data revealed that B
*
3902 and B
*
39013 differ by three nucleotide substitutions which result in a two amino acids change at residues 63 and 67, while one silent substitution at codon 312 is found between B
*
39011 and B
*
39013. These results suggest that B
*
3902 has evolved from B
*
39013 rather than B
*
39011.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers M94051 (HLA-B*39013), M94052 (HLA-B*39011), and M94053 (HLA-B*3902). 相似文献
32.
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34.
Hiroshige Taniguchi Tetsu Tsukada Sachiko Ootaki Yoshiaki Yamada Makoto Inoue 《Journal of applied physiology》2008,105(3):791-799
This study aimed to evaluate the effects of food texture and viscosity on the swallowing function by measuring tongue pressure and performing a videofluorographic (VF) examination. Eleven normal adults were recruited for this study. Test foods with different consistencies and liquid contents, i.e., a half-solid nutrient made of 0.8 and 1.5% agar powder, syrup, and a liquid containing 40 wt/vol% barium sulfate, were swallowed, and the anterior (AT) and posterior tongue pressures (PT) and electromyographic (EMG) activity of the suprahyoid muscles were recorded, together with VF images. The timing of each event obtained from EMG, tongue pressure, and VF recordings was measured and then compared. We found that the AT and PT activity patterns were similar and showed a single peak. The peak, area, and time duration of all of the variables for AT and PT and EMG burst increased with increasing hardness of the bolus. The onset of the EMG burst always preceded those of the AT and PT activities, while there were no significant differences in peak and offset times among EMG burst, AT, and PT. Total swallowing time and oral ejection time were significantly longer during the swallowing of 1.5% agar than any other boluses, while pharyngeal transit time and clearance time were significantly longer during the swallowing of syrup, which was as hard as the liquid, but showed a higher viscosity than the liquid. The results suggested that the major effects of food hardness were to delay oral ejection time, which strongly delays total swallowing time. In addition, pharyngeal bolus transit is not dependent on the hardness of food but on its viscosity. 相似文献
35.
Kioumars Ghamkhar Sachiko Isobe Phillip G. H. Nichols Troy Faithfull Megan H. Ryan Richard Snowball Shusei Sato Rudi Appels 《Molecular breeding : new strategies in plant improvement》2012,30(1):213-226
This study reports on the construction of the first genetic maps of subterranean clover (Trifolium subterraneum L.), a diploid, inbreeding annual pasture legume, and alignment of its linkage groups with those of red clover (T. pratense L.) and Medicago truncatula Gaertn. Transferability of red and white clover (T. repens L.) simple sequence repeat (SSR) markers to subterranean clover was observed. A total of 343 SSR loci were mapped into eight subterranean clover linkage groups, with 6?C31 loci per linkage group and 27 loci with similar locations between two distinct F 2 mapping populations. Phenotypic data obtained for flowering time, content of three isoflavonoids (formononetin, genistein and biochanin A), hardseededness, leaf markings, calyx pigmentation and hairiness of stems were analyzed, together with genotypic data. Genomic intervals influencing each trait were assigned to one to three chromosome regions, accounting for 5.5?C59.8% of the phenotypic variance. Syntenic relationships were observed among subterranean clover, red clover and Medicago truncatula genomes. Comparisons of loci shared between the three species indicated that at least two chromosomal regions have undergone duplications in the subterranean clover genome. Candidate genes for isoflavone content were identified using M. truncatula as a reference genome. Synteny-based segmentation observed in Brassicaceae chromosomes helped to account for the apparent segmental-based relationship between the clover genomes, particularly within the subterranean clover lines. The proposed segmental nature of clover genome could account for the extensive variation observed between the parental genotypes, while not preventing production of fertile intercrosses. 相似文献
36.
Prolyl 4-Hydroxylation of ��-Fibrinogen: A NOVEL PROTEIN MODIFICATION REVEALED BY PLASMA PROTEOMICS*
Masaya Ono Junichi Matsubara Kazufumi Honda Tomohiro Sakuma Tomoyo Hashiguchi Hiroshi Nose Shoji Nakamori Takuji Okusaka Tomoo Kosuge Naohiro Sata Hideo Nagai Tatsuya Ioka Sachiko Tanaka Akihiko Tsuchida Tatsuya Aoki Masashi Shimahara Yohichi Yasunami Takao Itoi Fuminori Moriyasu Ayako Negishi Hideya Kuwabara Ayako Shoji Setsuo Hirohashi Tesshi Yamada 《The Journal of biological chemistry》2009,284(42):29041-29049
Plasma proteome analysis requires sufficient power to compare numerous samples and detect changes in protein modification, because the protein content of human samples varies significantly among individuals, and many plasma proteins undergo changes in the bloodstream. A label-free proteomics platform developed in our laboratory, termed “Two-Dimensional Image Converted Analysis of Liquid chromatography and mass spectrometry (2DICAL),” is capable of these tasks. Here, we describe successful detection of novel prolyl hydroxylation of α-fibrinogen using 2DICAL, based on comparison of plasma samples of 38 pancreatic cancer patients and 39 healthy subjects. Using a newly generated monoclonal antibody 11A5, we confirmed the increase in prolyl-hydroxylated α-fibrinogen plasma levels and identified prolyl 4-hydroxylase A1 as a key enzyme for the modification. Competitive enzyme-linked immunosorbent assay of 685 blood samples revealed dynamic changes in prolyl-hydroxylated α-fibrinogen plasma level depending on clinical status. Prolyl-hydroxylated α-fibrinogen is presumably controlled by multiple biological mechanisms, which remain to be clarified in future studies.For comprehensive analysis of plasma proteins, it is necessary to compare a sufficient number of blood samples to avoid simple interindividual heterogeneity, because the protein content of human samples varies significantly among individuals. Also, the provision of sufficient power is needed to detect protein modification because many plasma proteins undergo changes in the bloodstream (1). Even though the proteomic technologies have advanced (2, 3), there remains room for improvement. Different isotope labeling and identification-based methods have been developed for quantitative proteomics technologies (4–6), but the number of samples that can be compared by the current isotope-labeling methods is limited, and identification-based proteomics is unable to capture information regarding unknown modifications.A label-free proteomics platform developed in our laboratory, termed “Two-Dimensional Image Converted Analysis of Liquid chromatography and mass spectrometry (2DICAL)2 (7), simply compares the liquid chromatography and mass spectrometry (LC-MS) data and detects a protein modification by finding changes in the mass to charge ratio (m/z) and retention time (RT). Enhanced methods for accurate MS peak alignment across multiple LC runs have enabled the successful implementation of clinical studies requiring comparison of a large number of samples (8, 9). Using 2DICAL to analyze plasma samples of pancreatic cancer patients and healthy controls, novel prolyl hydroxylation of α-fibrinogen was successfully discovered.Fibrinogen and its modification has been investigated because of its clinical importance (10, 11). On the other hand, prolyl hydroxylation has attracted attention after the discovery of the hypoxia-inducible factor 1α (HIF1α) prolyl-hydroxylase and its role in switching of HIF1α functions (12). Prolyl hydroxylation in other proteins has been energetically sought, but only a few such proteins have been identified (13). Only one study has reported prolyl hydroxylation of fibrinogen at the β chain (14).Here, we report the detection of prolyl 4-hydroxylated α-fibrinogen by plasma proteome analysis, a protein modification that dynamically changes in plasma depending on the clinical status and is a candidate plasma biomarker. 相似文献
37.
Goro?HANYAEmail author Miki?MATSUBARA Hideki?SUGIURA Sachiko?HAYAKAWA Shunji?GOTO Toshiaki?TANAKA Joseph?SOLTIS Naohiko?NOMA 《Ecological Research》2004,19(2):179-188
The mass mortality of wild Japanese macaques (Macaca fuscata Blyth) was observed in a warm temperate forest of Yakushima, southern Japan. Demographic changes of eight troops between August 1998 and August 1999 were studied and 56% of macaques disappeared from the five intensively studied troops. Mortality varied among troops: two troops became extinct, while another troop did not decrease in size. The rate of mortality of the other troops was between 33 and 80%. The variation in mortality among the troops was either the outcome of local concentrations of mortality or of intertroop competition. The rate of mortality decreased with increasing distance from the two extinct troops and with increasing troop size; these two factors could not be separated statistically. The direct cause of death was diagnosed as pneumonia for four out of five fresh carcasses. The fleshy fruit production in autumn 1998 was the lowest in 14years, and macaques had relied on leaves earlier than in usual years. It was exceptionally hot and dry in the summer of 1998. The exceptionally poor fruit production and hot summer of this year, with the resulting shortage of high-quality foods, was consistent with the scenario that mass mortality was due to the poor nutritional conditions. However, the possibility that epidemics caused the mass mortality cannot be ruled out. Our findings proved that primates in a seemingly stable habitat experience fluctuations in demographic parameters under natural conditions. 相似文献
38.
Sachiko Komatsu Ayaka Yaguchi Kouwa Yamashita Masao Nagaoka Mitsuteru Numazawa 《Steroids》2009,74(12):884-889
Inhibition of aromatase is an efficient approach for the prevention and treatment of breast cancer. New 6β,19-bridged steroid analogs of androstenedione, 6β,19-epithio- and 6β,19-methano compounds 11 and 17, were synthesized starting from 19-hydroxyandrostenedione (6) and 19-formylandrost-5-ene-3β,17β-yl diacetate (12), respectively, as aromatase inhibitors. All of the compounds including known steroids 6β,19-epoxyandrostenedione (4) and 6β,19-cycloandrostenedione (5) tested were weak to poor competitive inhibitors of aromatase and, among them, 6β,19-epoxy steroid 4 provided only moderate inhibition (Ki: 2.2 μM). These results show that the 6β,19-bridged groups of the inhibitors interfere with binding in active site of aromatase. 相似文献
39.
Transcriptomic analysis indicates putative metabolic changes caused by manipulation of phosphorus availability in rice leaves 总被引:10,自引:0,他引:10
40.
Cardiac neural crest cells contribute to the dormant multipotent stem cell in the mammalian heart 总被引:11,自引:0,他引:11 下载免费PDF全文
Tomita Y Matsumura K Wakamatsu Y Matsuzaki Y Shibuya I Kawaguchi H Ieda M Kanakubo S Shimazaki T Ogawa S Osumi N Okano H Fukuda K 《The Journal of cell biology》2005,170(7):1135-1146
Arodent cardiac side population cell fraction formed clonal spheroids in serum-free medium, which expressed nestin, Musashi-1, and multi-drug resistance transporter gene 1, markers of undifferentiated neural precursor cells. These markers were lost following differentiation, and were replaced by the expression of neuron-, glial-, smooth muscle cell-, or cardiomyocyte-specific proteins. Cardiosphere-derived cells transplanted into chick embryos migrated to the truncus arteriosus and cardiac outflow tract and contributed to dorsal root ganglia, spinal nerves, and aortic smooth muscle cells. Lineage studies using double transgenic mice encoding protein 0-Cre/Floxed-EGFP revealed undifferentiated and differentiated neural crest-derived cells in the fetal myocardium. Undifferentiated cells expressed GATA-binding protein 4 and nestin, but not actinin, whereas the differentiated cells were identified as cardiomyocytes. These results suggest that cardiac neural crest-derived cells migrate into the heart, remain there as dormant multipotent stem cells-and under the right conditions-differentiate into cardiomyocytes and typical neural crest-derived cells, including neurons, glia, and smooth muscle. 相似文献