44 results on '"Maehara K"'
Search Results
2. Application of the unique redox properties of magnesium ortho-vanadate incorporated with palladium in the unsteady-state operation of the oxidative dehydrogenation of propane
- Author
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Sugiyama, S., Hirata, Y., Nakagawa, K., Sotowa, K.-I., Maehara, K., Himeno, Y., and Ninomiya, W.
- Published
- 2008
- Full Text
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3. Alteration in haemodynamics and pathological changes in the cardiovascular system during the development of Type 2 diabetes mellitus in OLETF rats
- Author
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Saito, F., Kawaguchi, M., Izumida, J., Asakura, T., Maehara, K., and Maruyama, Y.
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- 2003
- Full Text
- View/download PDF
4. Geochemistry of kimberlites from the Nakyn field, Siberia: evidence for unique source composition
- Author
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Agashev, A.M., Watanabe, T., Bydaev, D.A., Pokhilenko, N.P., Fomin, A.S., Maehara, K., and Maeda, J.
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Siberia -- Natural history ,Kimberlite -- Research ,Mineralogical chemistry -- Research ,Earth sciences - Abstract
Two newly discovered kimberlite pipes in the Nakyn field, Siberia yield Rb-Sr isochron ages of ca. 364 Ma, similar to emplacement ages of other major diamond-bearing pipes on the Siberian platform. Unlike any other Siberian kimberlites, however, the rocks from the Nakyn field show some similarities to South African group II (micaceous) kimberlites in their mineralogy and chemical compositions. Several key geochemical ratios (Ti[O.sub.2]/[K.sub.2]O, 0.43; Nb/Zr, 0.4) in the Nakyn kimberlites are the same as for group II, whereas others such as Ba/Nb (0.95) and Ni/MgO (45.2) are intermediate between groups I and II, and La/Nb (0.58) ratios are similar to group I kimberlites. The Nakyn kimberlites are unique in having concentrations of incompatible elements two to three times lower than kimberlites from any cratonic area worldwide, coupled with higher Sm/Nd (0.21) and Lu/Hf (0.06) and lower La/Yb (25.8). Ranges of initial Sr and Nd isotope composition are very narrow in the Nakyn kimberlites, at [[epsilon].sub.Nd](t) +0.9 to -0.7 and [sup.87]Sr/[sup.86]Sr(t) 0.7059-0.7068. These compositions are closer to group I than to group II kimberlites, but they require a source with higher Rb/Sr and lower Sm/Nd ratios than Group I kimberlites from both Siberia and South Africa. The trace element and isotope signatures of the Nakyn kimberlites appear to indicate a specific source located within the lithospheric mantle, distinct from that of other Siberian kimberlites. Keywords: kimberlite, geochemistry, Siberia, St, Nd, isotopes.
- Published
- 2001
5. Testis-Specific Histone Variant H3t Gene Is Essential for Entry into Spermatogenesis
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Ueda, J., Harada, A., Urahama, T., Machida, S., Maehara, K., Hada, M., Makino, Y., Nogami, J., Horikoshi, N., Osakabe, A., Taguchi, H., Tanaka, H., Tachiwana, H., Yao, T., Yamada, M., Iwamoto, T., Isotani, A., Ikawa, M., Tachibana, T., Okada, Y., Kimura, Hiroshi, Ohkawa, Y., Kurumizaka, H., and Yamagata, K.
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Male ,0301 basic medicine ,endocrine system ,crystal structure ,testes ,Cell Cycle Proteins ,Haploidy ,General Biochemistry, Genetics and Molecular Biology ,Chromatin remodeling ,Histones ,Mice ,03 medical and health sciences ,Histone H3 ,spermatogonial differentiation ,Histone H1 ,spermatozoa ,Testis ,Histone methylation ,Histone H2A ,Animals ,Histone code ,meiosis ,Amino Acid Sequence ,lcsh:QH301-705.5 ,reproductive and urinary physiology ,Cells, Cultured ,Adaptor Proteins, Signal Transducing ,Azoospermia ,Epigenomics ,Mice, Knockout ,Genetics ,histone variant ,030102 biochemistry & molecular biology ,biology ,epigenetics ,urogenital system ,nucleosome ,Cell Differentiation ,Spermatogonia ,spermatogenesis ,Nucleosomes ,Mice, Inbred C57BL ,Germ Cells ,030104 developmental biology ,Histone ,lcsh:Biology (General) ,biology.protein ,chromatin - Abstract
Jun Ueda, Akihito Harada, Takashi Urahama, Shinichi Machida, Kazumitsu Maehara, Masashi Hada, Yoshinori Makino, Jumpei Nogami, Naoki Horikoshi, Akihisa Osakabe, Hiroyuki Taguchi, Hiroki Tanaka, Hiroaki Tachiwana, Tatsuma Yao, Minami Yamada, Takashi Iwamoto, Ayako Isotani, Masahito Ikawa, Taro Tachibana, Yuki Okada, Hiroshi Kimura, Yasuyuki Ohkawa, Hitoshi Kurumizaka, Kazuo Yamagata, Testis-Specific Histone Variant H3t Gene Is Essential for Entry into Spermatogenesis, Cell Reports, Volume 18, Issue 3, 2017, Pages 593-600, ISSN 2211-1247, https://doi.org/10.1016/j.celrep.2016.12.065., Cellular differentiation is associated with dynamic chromatin remodeling in establishing a cell-type-specific epigenomic landscape. Here, we find that mouse testis-specific and replication-dependent histone H3 variant H3t is essential for very early stages ofspermatogenesis. H3t gene deficiency leads to azoospermia because of the loss of haploid germ cells. When differentiating spermatogonia emerge in normal spermatogenesis, H3t appears and replaces the canonical H3 proteins. Structural and biochemical analyses reveal that H3t-containing nucleosomes are more flexible than the canonical nucleosomes. Thus, by incorporating H3t into the genome during spermatogonial differentiation, male germ cells are able to enter meiosis and beyond.
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- 2017
6. Structure and function of human histone H3.Y nucleosome
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Kujirai, T., Horikoshi, N., Sato, K., Maehara, K., Machida, S., Osakabe, A., Kimura, Hiroshi, Ohkawa, Y., and Kurumizaka, H.
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0301 basic medicine ,Transcription, Genetic ,Biology ,Histones ,Histone H3 ,03 medical and health sciences ,Histone H1 ,Histone methylation ,Genetics ,Histone code ,Nucleosome ,Humans ,Histone octamer ,030102 biochemistry & molecular biology ,Gene regulation, Chromatin and Epigenetics ,DNA ,Linker DNA ,Chromatin ,Structure and function ,Cell biology ,Nucleosomes ,030104 developmental biology ,Histone ,Biochemistry ,Chromatosome ,Nucleic acid ,biology.protein ,Transcription Initiation Site ,Corrigendum ,Transcription Factors - Abstract
Histone H3.Y is a primate-specific, distant H3 variant. It is evolutionarily derived from H3.3, and may function in transcription regulation. However, the mechanism by which H3.Y regulates transcription has not been elucidated. In the present study, we determined the crystal structure of the H3.Y nucleosome, and found that many H3.Y-specific residues are located on the entry/exit sites of the nucleosome. Biochemical analyses revealed that the DNA ends of the H3.Y nucleosome were more flexible than those of the H3.3 nucleosome, although the H3.Y nucleosome was stable in vitro and in vivo. Interestingly, the linker histone H1, which compacts nucleosomal DNA, appears to bind to the H3.Y nucleosome less efficiently, as compared to the H3.3 nucleosome. These characteristics of the H3.Y nucleosome are also conserved in the H3.Y/H3.3 heterotypic nucleosome, which may be the predominant form in cells. In human cells, H3.Y preferentially accumulated around transcription start sites (TSSs). Taken together, H3.Y-containing nucleosomes around transcription start sites may form relaxed chromatin that allows transcription factor access, to regulate the transcription status of specific genes.
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- 2016
7. Application of Soil Improvement by Sodium Silicate-based Grouting on Indonesian Sand
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Shimada, H., Wahyudi, S., Asano, S., Maehara, K., Sasaoka, T., and Akihiro Hamanaka
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Sodium Silicate ,Soil Improvement ,Grouting Material ,Indonesian Soil - Abstract
In recent years, demand for infrastructure development is increasing due to satisfy the high rates of economic growth in Indonesia. Therefore, it is desired to introduce the chemical grouting which is widely used in Japan as ground improvement in underground construction. The chemical grouting constructions have been prohibited since the accidents, because of polymeric chemicals pollution. Considering it, in order to reduce environmental issues, sodium silicate chemicals as lowest toxicity material is considered in the chemical grouting. Furthermore, there is no study about sodium silicate chemicals in Indonesia. Hence, in this paper, applicability of the chemical grouting of sodium silicate chemicals in Indonesia is discussed from the aspects of its functions. In this study, the chemical grouts were injected into the samples of Indonesian sands. After solidification of the chemical grouts, permeability and strength of the samples have been measured by falling the head hydraulic conductivity test and UCS test. As the conclusion, the study shows that chemical grouting is applicable to improve Indonesian sand.
- Published
- 2018
8. Incorporation of histone H3.1 suppresses the lineage potential of skeletal muscle
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Harada, A., Maehara, K., Sato, Y., Konno, D., Tachibana, T., Kimura, Hiroshi, and Ohkawa, Y.
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Histones/*metabolism ,Muscle Fibers, Skeletal/metabolism ,Muscle, Skeletal/*embryology/metabolism ,Muscle Fibers, Skeletal ,Biology ,Muscle Development ,Methylation ,Cell Line ,Histones ,Histone H3 ,Mice ,Cell Lineage/genetics ,Genetics ,medicine ,Animals ,Cell Lineage ,Muscle, Skeletal ,Promoter Regions, Genetic ,Regulation of gene expression ,Muscle Development/*genetics ,Myogenesis ,Gene regulation, Chromatin and Epigenetics ,Skeletal muscle ,Gene Expression Regulation, Developmental ,Molecular biology ,Chromatin ,medicine.anatomical_structure ,Histone ,biology.protein ,H3K4me3 ,C2C12 - Abstract
Lineage potential is triggered by lineage-specific transcription factors in association with changes in the chromatin structure. Histone H3.3 variant is thought to play an important role in the regulation of lineage-specific genes. To elucidate the function of H3.3 in myogenic differentiation, we forced the expression of GFP-H3.1 to alter the balance between H3.1 and H3.3 in mouse C2C12 cells that could be differentiated into myotubes. GFP-H3.1 replaced H3.3 in the regulatory regions of skeletal muscle (SKM) genes and induced a decrease of H3K4 trimethylation (H3K4me3) and increase of H3K27 trimethylation (H3K27me3). Similar results were obtained by H3.3 knockdown. In contrast, MyoD-dependent H3.3 incorporation into SKM genes in fibroblasts induced an increase of H3K4me3 and H3K27me3. In mouse embryos, a bivalent modification of H3K4me3 and H3K27me3 was formed on H3.3-incorporated SKM genes before embryonic skeletal muscle differentiation. These results suggest that lineage potential is established through a selective incorporation of specific H3 variants that governs the balance of histone modifications.
- Published
- 2015
9. Histone H4 lysine 20 acetylation is associated with gene repression in human cells
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Kaimori, J. Y., Maehara, K., Hayashi-Takanaka, Y., Harada, A., Fukuda, M., Yamamoto, S., Ichimaru, N., Umehara, T., Yokoyama, S., Matsuda, R., Ikura, T., Nagao, K., Obuse, C., Nozaki, N., Takahara, S., Takao, T., Ohkawa, Y., Kimura, Hiroshi, and Isaka, Y.
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0301 basic medicine ,Chromatin Immunoprecipitation ,Biology ,SAP30 ,Methylation ,Article ,Histone H4 ,Histones ,03 medical and health sciences ,Histone H3 ,Mice ,0302 clinical medicine ,Histone H2A ,Nucleosome ,Histone code ,Animals ,Humans ,Transcription Factors/metabolism ,Histone octamer ,Antibodies, Monoclonal/immunology ,Chromatography, High Pressure Liquid ,Multidisciplinary ,Binding Sites ,Lysine ,Antibodies, Monoclonal ,Acetylation ,Peptides/analysis ,Molecular biology ,030104 developmental biology ,Microscopy, Fluorescence ,Histone methyltransferase ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Transcription Initiation Site ,Peptides ,Histones/immunology/*metabolism ,030217 neurology & neurosurgery ,Lysine/metabolism ,HeLa Cells ,Transcription Factors - Abstract
Histone acetylation is generally associated with gene activation and chromatin decondensation. Recent mass spectrometry analysis has revealed that histone H4 lysine 20, a major methylation site, can also be acetylated. To understand the function of H4 lysine 20 acetylation (H4K20ac), we have developed a specific monoclonal antibody and performed ChIP-seq analysis using HeLa-S3 cells. H4K20ac was enriched around the transcription start sites (TSSs) of minimally expressed genes and in the gene body of expressed genes, in contrast to most histone acetylation being enriched around the TSSs of expressed genes. The distribution of H4K20ac showed little correlation with known histone modifications, including histone H3 methylations. A motif search in H4K20ac-enriched sequences, together with transcription factor binding profiles based on ENCODE ChIP-seq data, revealed that most transcription activators are excluded from H4K20ac-enriched genes and a transcription repressor NRSF/REST co-localized with H4K20ac. These results suggest that H4K20ac is a unique acetylation mark associated with gene repression.
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- 2016
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10. Tissue-specific expression of histone H3 variants diversified after species separation
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Maehara, K., Harada, A., Sato, Y., Matsumoto, M., Nakayama, K. I., Kimura, Hiroshi, and Ohkawa, Y.
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Genetics ,Histone H3 ,Histone H1 ,Histone methyltransferase ,Research ,Histone H2A ,Histone methylation ,Histone code ,Biology ,Molecular Biology ,Genome ,Chromatin - Abstract
Background The selective incorporation of appropriate histone variants into chromatin is critical for the regulation of genome function. Although many histone variants have been identified, a complete list has not been compiled. Results We screened mouse, rat and human genomes by in silico hybridization using canonical histone sequences. In the mouse genome, we identified 14 uncharacterized H3 genes, among which 13 are similar to H3.3 and do not have human or rat counterparts, and one is similar to human testis-specific H3 variant, H3T/H3.4, and had a rat paralog. Although some of these genes were previously annotated as pseudogenes, their tissue-specific expression was confirmed by sequencing the 3′-UTR regions of the transcripts. Certain new variants were also detected at the protein level by mass spectrometry. When expressed as GFP-tagged versions in mouse C2C12 cells, some variants were stably incorporated into chromatin and the genome-wide distributions of most variants were similar to that of H3.3. Moreover, forced expression of H3 variants in chromatin resulted in alternate gene expression patterns after cell differentiation. Conclusions We comprehensively identified and characterized novel mouse H3 variant genes that encoded highly conserved amino acid sequences compared to known histone H3. We speculated that the diversity of H3 variants acquired after species separation played a role in regulating tissue-specific gene expression in individual species. Their biological relevance and evolutionary aspect involving pseudogene diversification will be addressed by further functional analysis. Electronic supplementary material The online version of this article (doi:10.1186/s13072-015-0027-3) contains supplementary material, which is available to authorized users.
- Published
- 2015
11. Histone H3.5 forms an unstable nucleosome and accumulates around transcription start sites in human testis
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Urahama, T., Harada, A., Maehara, K., Horikoshi, N., Sato, K., Sato, Y., Shiraishi, K., Sugino, N., Osakabe, A., Tachiwana, H., Kagawa, W., Kimura, Hiroshi, Ohkawa, Y., and Kurumizaka, H.
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0301 basic medicine ,Genetics ,030102 biochemistry & molecular biology ,biology ,Research ,Chromatin ,Cell biology ,Histone H4 ,03 medical and health sciences ,Histone H3 ,030104 developmental biology ,Histone ,Histone H1 ,Histone variant ,Transcription start site ,Nucleosome ,Histone H2A ,Testis ,biology.protein ,Histone code ,Spermatogenesis ,Chromatin immunoprecipitation ,Molecular Biology - Abstract
Background Human histone H3.5 is a non-allelic H3 variant evolutionally derived from H3.3. The H3.5 mRNA is highly expressed in human testis. However, the function of H3.5 has remained poorly understood. Results We found that the H3.5 nucleosome is less stable than the H3.3 nucleosome. The crystal structure of the H3.5 nucleosome showed that the H3.5-specific Leu103 residue, which corresponds to the H3.3 Phe104 residue, reduces the hydrophobic interaction with histone H4. Mutational analyses revealed that the H3.5-specific Leu103 residue is responsible for the instability of the H3.5 nucleosome, both in vitro and in living cells. The H3.5 protein was present in human seminiferous tubules, but little to none was found in mature sperm. A chromatin immunoprecipitation coupled with sequencing analysis revealed that H3.5 accumulated around transcription start sites (TSSs) in testicular cells. Conclusions We performed comprehensive studies of H3.5, and found the instability of the H3.5 nucleosome and the accumulation of H3.5 protein around TSSs in human testis. The unstable H3.5 nucleosome may function in the chromatin dynamics around the TSSs, during spermatogenesis.
- Published
- 2016
12. Human TREX component Thoc5 affects alternative polyadenylation site choice by recruiting mammalian cleavage factor I
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Katahira, J., primary, Okuzaki, D., additional, Inoue, H., additional, Yoneda, Y., additional, Maehara, K., additional, and Ohkawa, Y., additional
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- 2013
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13. Development of a Compact Measurement System of Transport Characteristics in HTS Conductors by Using an HTS Current
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Kawabata, S., primary, Hirayama, T., additional, Maehara, K., additional, and Kirihara, Y., additional
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- 2011
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14. Effectiveness in psychiatric care: II. Outcome for the family after hospital treatment for major affective disorder
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Glick, I. D., Burti, Lorenzo, Minakawa, K., and Maehara, K.
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PSYA ,Psichiatria - Published
- 1991
15. Attenuated cardioprotection by ischemic preconditioning in coronary stenosed heart and its restoration by carvedilol
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WATANABE, K, primary, YAOITA, H, additional, OGAWA, K, additional, OIKAWA, M, additional, MAEHARA, K, additional, and MARUYAMA, Y, additional
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- 2006
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16. Different therapeutic responses to treadmill exercise of heart failure due to ischemia and infarction in rats
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YOSHINARI, K, primary, YAOITA, H, additional, MAEHARA, K, additional, and MARUYAMA, Y, additional
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- 2005
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17. Functional interference between estrogen-related receptor alpha and peroxisome proliferator-activated receptor alpha/9-cis-retinoic acid receptor alpha heterodimer complex in the nuclear receptor response element-1 of the medium chain acyl-coenzyme A dehydrogenase gene
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Maehara, K, primary, Hida, T, additional, Abe, Y, additional, Koga, A, additional, Ota, K, additional, and Kutoh, E, additional
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- 2003
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18. Impaired fibrinolysis in coronary atherectomy specimens in acute coronary syndromes: Increased plasminogen activator inhibitor-1 and apolipoprotein(a)
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Sakamoto, T., primary, Ishibashi, T., additional, Shindo, J., additional, Kijima, M., additional, Nakazato, K., additional, Nagata, K., additional, Hirosaka, A., additional, Maehara, K., additional, Saitoh, T., additional, and Maruyama, Y., additional
- Published
- 2000
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19. Biochemical changes in the cervical tissue of rabbit induced by interleukin-8, interleukin-1 dehydroepiandrosterone sulphate and prostaglandin E2: a comparative study
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Maradny, E. E., primary, Kanayama, N., additional, Halim, A., additional, Maehara, K., additional, Sumimoto, K., additional, and Terao, T., additional
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- 1996
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20. Nonadrenergic noncholinergic nerves regulate basal coronary flow via release of capsaicin-sensitive neuropeptides in the rat heart.
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Yaoita, H, primary, Sato, E, additional, Kawaguchi, M, additional, Saito, T, additional, Maehara, K, additional, and Maruyama, Y, additional
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- 1994
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21. Biochemical changes in the cervical tissue of rabbit induced by interleukin-8, interleukin-1beta, dehydroepiandrosterone sulphate and prostaglandin E2: a comparative study.
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El Maradny, E, Kanayama, N, Halim, A, Maehara, K, Sumimoto, K, and Terao, T
- Abstract
The aim of this research was to study and compare the mechanism of action of interleukin (IL)-8, IL-1beta dehydroepiandrosterone sulphate (DHEA-S) and prostaglandin (PG)E2 on the cervix. Five equal groups of pregnant rabbits (n = 45) were tested by either placebo or tested drugs in the form of vaginal suppositories once daily for 3 days. The suppositories contained human recombinant IL-8 (100 ng), IL-1beta (200 ng), DHEA-S (10 mg) or PGE2 (1 mg). All rabbits were tested by one dose, two doses or three doses. Consistency, dilatation and water contents were estimated 24 h after the last dose of treatment. Leukocyte infiltration of the cervices was studied after staining the cervical tissue sections with antirabbit RT2 monoclonal antibodies. Relative collagen concentration was assessed after staining with Picrosirius Red. Collagenase, gelatinase and elastase activities were measured in 100 mg of homogenized cervical connective tissue. Water contents were significantly increased in all tested cervices. Neutrophil numbers were increased in IL-8 and IL-1beta groups after the second dose of treatment (P < 0.0005 and 0.001 respectively). In the PGE2 group, neutrophils were increased after the third dose of treatment, whereas in DHEA-S group no significant changes were observed. Collagen content was significantly decreased in IL-8, IL-1beta and PGE2 groups after the first dose of treatment (P < 0.004, and 0.005 and 0.03 respectively). In the DHEA-S group, the decrease in collagen content occurred after the third dose (P < 0.05). Collagenase activity was markedly increased in IL-8, IL-1, and DHEA-S groups after the second dose of treatment (P < 0.001, 0.003 and 0.007 respectively). No significant increase in collagenase activity was found in PGE2 group. Gelatinase activity was significantly increased in IL-8, IL-1beta, PGE2 and DHEA-S groups after the second dose of treatment (P < 0.008, 0.01, 0.003 and 0.05 respectively). Also, elastase activity was increased after the second dose of treatment in all groups (P < 0.001, 0.001, 0.001 and 0.006 respectively). Our data suggest that ripening of the cervix in rabbit can be initiated by different mechanisms. Cytokines play a vital role in cervical ripening, especially IL-8 and IL-1. IL-8 is one of the factors which could ripen the cervix in a manner similar to the physiological process at term. [ABSTRACT FROM AUTHOR]
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- 1996
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22. Dentato-rubro-pallido-luysian atrophy: a clinico-pathological study.
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Iizuka, R, Hirayama, K, and Maehara, K A
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BASAL ganglia ,BRAIN ,BRAIN stem ,CELLS ,CEREBELLAR ataxia ,CEREBELLUM ,CHOREA ,DEGENERATION (Pathology) ,DEMYELINATION ,NEURODEGENERATION ,NEURONS ,NYSTAGMUS ,SPEECH disorders ,SPINAL cord ,THALAMUS ,ATROPHY - Abstract
Clinical and neuropathological descriptions are given of four cases of an uncommon disease, characterised by simultaneous degeneration of the dentato-rubral and pallido-luysian systems. These four are compared with sixteen previously described cases, and the group as a whole is compared and contrasted with other multisystem degenerations, such as olivo-ponto-cerebellar atrophy and Friedreich's ataxia. A pathological feature described here for the first time is degeneration of the fastigio-vestibular system. Clinically, there are three main types of the disease; (1) an ataxo-choreoathetoid type, (2) a pseudo-Huntington type, and (3) a myoclonic-epileptic type. There are familial cases of types 2 and 3. Oculomotor disturbances, associated with atrophy of the brainstem tegmentum, are observed in cases of types 1 and 3. [ABSTRACT FROM AUTHOR]
- Published
- 1984
23. Distribution of histone H4 modifications as revealed by a panel of specific monoclonal antibodies
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Hayashi-Takanaka, Y., Maehara, K., Harada, A., Umehara, T., Yokoyama, S., Obuse, C., Ohkawa, Y., Nozaki, N., and Kimura, Hiroshi
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Monoclonal antibody ,Chromatin Immunoprecipitation ,Blotting, Western ,Methylation ,Article ,Epigenesis, Genetic ,Histone H4 ,Histones ,Mice ,Histone H2A ,Histone methylation ,Genetics ,Histone code ,Animals ,Humans ,Epigenomics ,Cell Line, Transformed ,biology ,Antibodies, Monoclonal ,High-Throughput Nucleotide Sequencing ,Acetylation ,Immunohistochemistry ,Chromatin ,Histone ,Biochemistry ,Histone methyltransferase ,Immunoglobulin G ,biology.protein ,Epigenetics ,Histone modification ,Chromatin immunoprecipitation ,Protein Processing, Post-Translational ,HeLa Cells - Abstract
Post-translational histone modifications play a critical role in genome functions such as epigenetic gene regulation and genome maintenance. The tail of the histone H4 N-terminus contains several amino acids that can be acetylated and methylated. Some of these modifications are known to undergo drastic changes during the cell cycle. In this study, we generated a panel of mouse monoclonal antibodies against histone H4 modifications, including acetylation at K5, K8, K12, and K16, and different levels of methylation at K20. Their specificity was evaluated by ELISA and immunoblotting using synthetic peptide and recombinant proteins that harbor specific modifications or amino acid substitutions. Immunofluorescence confirmed the characteristic distributions of target modifications. An H4K5 acetylation (H4K5ac)-specific antibody CMA405 reacted with K5ac only when the neighboring K8 was unacetylated. This unique feature allowed us to detect newly assembled H4, which is diacetylated at K5 and K12, and distinguish it from hyperacetylated H4, where K5 and K8 are both acetylated. Chromatin immunoprecipiation combined with deep sequencing (ChIP-seq) revealed that acetylation of both H4K8 and H4K16 were enriched around transcription start sites. These extensively characterized and highly specific antibodies will be useful for future epigenetics and epigenome studies.
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24. Cooperative interaction of NF-@kB and C/EBP binding sites is necessary for manganese superoxide dismutase gene transcription mediated by lipopolysaccharide and interferon-@c
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Maehara, K., Hasegawa, T., Xiao, H., Takeuchi, A., Abe, R., and Isobe, K.-i.
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- 1999
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25. Fundamental study on application of underpinning method using pipe jacking by means of numerical simulation
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Maehara, K., Shimada, H., Sasaoka, T., Akihiro Hamanaka, Matsumoto, F., and Morita, T.
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3D Finite Element Analysis ,Underpinning Method ,Pipe Jacking ,Underground - Abstract
In recent years, the underground space has overcrowded with the overcrowding of urban areas. Therefore, the adjacent construction of underground structures is increasing. In such a construction, an influence of the construction of a new structure on the existing structure has to be considered. In order to minimize the influence on such existing structures, application of the underpinning method is expected. The underpinning method is a construction method that attempts to reduce the influence on the existing structures by excavating the ground around existing structures with constructing, rebuilding, and reinforcing new foundations. This study focuses on the underpinning method using pipe jacking. In order to ensure the effectiveness of the underpinning method, 3D finite element analysis was carried out. In particular, four major considerable factors were discussed: the influence of pipe presence, comparison of using conventional underpinning and pipe jacking, the influence of the distance between the pipes and new structure, the influence of pipe length. Based on the numerical results, it is possible to reduce the vertical displacement on the existing structure by using the underpinning method using pipe jacking. Additionally, the underpinning method using pipe jacking is effective to reduce the displacement over a wide range compared with the conventional underpinning method. Furthermore, the influence on the existing structure and the surrounding ground can be minimized by adopting the proper distance of pipe length and the space between the pipes and the new structure.
26. -159-THE DELINEATION OF LEFT VENTRICULAR EPICARDIAL SURFACE FROM BIPLANE CINE CORONARY ANGIOGRAM
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Ino-Oka, E, primary, Kagaya, Y, additional, Maehara, K, additional, Kanatsuka, H, additional, Ashikawa, K, additional, and Takishima, T, additional
- Published
- 1986
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27. Heterochromatin Dynamics during the Differentiation Process Revealed by the DNA Methylation Reporter Mouse, MethylRO
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Ueda, J., Maehara, K., Mashiko, D., Ichinose, T., Yao, T., Hori, M., Sato, Y., Kimura, Hiroshi, Ohkawa, Y., and Yamagata, K.
- Subjects
Resource ,Male ,Heterochromatin ,viruses ,cells ,Cell Differentiation/genetics/physiology ,Biology ,Biochemistry ,environment and public health ,Heterochromatin/*metabolism ,Mice ,Epigenetics of physical exercise ,Genetics ,Animals ,Immunoprecipitation ,Methylated DNA immunoprecipitation ,RNA-Directed DNA Methylation ,Process (anatomy) ,lcsh:QH301-705.5 ,Epigenomics ,lcsh:R5-920 ,DNA Methylation/genetics/*physiology ,EZH2 ,Dynamics (mechanics) ,Cell Differentiation ,Cell Biology ,DNA Methylation ,Chromatin ,Cell biology ,Mice, Inbred C57BL ,lcsh:Biology (General) ,DNA methylation ,health occupations ,Female ,Stem cell ,Erratum ,biological phenomena, cell phenomena, and immunity ,lcsh:Medicine (General) ,Developmental Biology - Abstract
Summary In mammals, DNA is methylated at CpG sites, which play pivotal roles in gene silencing and chromatin organization. Furthermore, DNA methylation undergoes dynamic changes during development, differentiation, and in pathological processes. The conventional methods represent snapshots; therefore, the dynamics of this marker within living organisms remains unclear. To track this dynamics, we made a knockin mouse that expresses a red fluorescent protein (RFP)-fused methyl-CpG-binding domain (MBD) protein from the ROSA26 locus ubiquitously; we named it MethylRO (methylation probe in ROSA26 locus). Using this mouse, we performed RFP-mediated methylated DNA immunoprecipitation sequencing (MeDIP-seq), whole-body section analysis, and live-cell imaging. We discovered that mobility and pattern of heterochromatin as well as DNA methylation signal intensity inside the nuclei can be markers for cellular differentiation status. Thus, the MethylRO mouse represents a powerful bioresource and technique for DNA methylation dynamics studies in developmental biology, stem cell biology, as well as in disease states., Graphical Abstract, Highlights • Changes in DNA methylation are tracked in living mice • Heterochromatin structure changes dynamically during development and differentiation • Heterochromatin of preimplantation embryonic cells is highly dynamic than ESCs • Heterochromatin pattern in nucleus can be a marker for cell differentiation states, DNA methylation undergoes dynamic changes during development, differentiation, and in pathological processes. To track these dynamics, DNA methylation reporter mouse was generated and named MethylRO (methylation probe in ROSA26 locus). Using this mouse, Yamagata and colleagues discovered that mobility and pattern of heterochromatin as well as DNA methylation signal intensity inside the nuclei can be markers for cellular differentiation status.
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28. The classification of mRNA expression levels by the phosphorylation state of RNAPII CTD based on a combined genome-wide approach
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Tachibana Taro, Maehara Kazumitsu, Yoshimi Tomohiko, Harada Akihito, Odawara Jun, Okada Seiji, Akashi Koichi, and Ohkawa Yasuyuki
- Subjects
Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Cellular function is regulated by the balance of stringently regulated amounts of mRNA. Previous reports revealed that RNA polymerase II (RNAPII), which transcribes mRNA, can be classified into the pausing state and the active transcription state according to the phosphorylation state of RPB1, the catalytic subunit of RNAPII. However, genome-wide association between mRNA expression level and the phosphorylation state of RNAPII is unclear. While the functional importance of pausing genes is clear, such as in mouse Embryonic Stem cells for differentiation, understanding this association is critical for distinguishing pausing genes from active transcribing genes in expression profiling data, such as microarrays and RNAseq. Therefore, we examined the correlation between the phosphorylation of RNAPII and mRNA expression levels using a combined analysis by ChIPseq and RNAseq. Results We first performed a precise quantitative measurement of mRNA by performing an optimized calculation in RNAseq. We then visualized the recruitment of various phosphorylated RNAPIIs, such as Ser2P and Ser5P. A combined analysis using optimized RNAseq and ChIPseq for phosphorylated RNAPII revealed that mRNA levels correlate with the various phosphorylation states of RNAPII. Conclusions We demonstrated that the amount of mRNA is precisely reflected by the phased phosphorylation of Ser2 and Ser5. In particular, even the most "pausing" genes, for which only Ser5 is phosphorylated, were detectable at a certain level of mRNA. Our analysis indicated that the complexity of quantitative regulation of mRNA levels could be classified into three categories according to the phosphorylation state of RNAPII.
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- 2011
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29. Defects in the H3t Gene Cause an Increase in Leydig Cells With Impaired Spermatogenesis in Mice.
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Wu Q, Ito M, Fujii T, Tanaka K, Nakatani K, Izumi Y, Bamba T, Baba T, Maehara K, Tomimatsu K, Takemoto T, Ohkawa Y, and Harada A
- Subjects
- Animals, Male, Mice, Testis metabolism, Testosterone metabolism, Mice, Inbred C57BL, Infertility, Male genetics, Infertility, Male metabolism, Leydig Cells metabolism, Spermatogenesis genetics, Histones metabolism
- Abstract
Abnormalities in spermatogenesis, a fundamental component of male reproductive function, can cause male infertility. Somatic cells constituting the testis microenvironment are essential for controlling normal spermatogenesis. Although testicular somatic cells are thought to sense and respond to germ cells to ensure proper spermatogenesis, the details of this signaling mechanism are unknown. Here, we investigated somatic cell dynamics in testicular tissue lacking spermatogenesis using the mice with deletion of the testis-specific histone H3 variant gene H3t. Testicular tissue sections of H3t
Δ/Δ mice exhibited an increased interstitial area compared with those of wild-type mice, which was primarily attributed to an increase in Leydig cell numbers. Furthermore, this increase in Leydig cells led to increased testosterone synthesis, which occurred alongside cellular senescence-associated β-galactosidase activity. These findings suggest that Leydig cells monitor the progress of spermatogenesis and possess a mechanism to promote functional germ cell formation., (© 2024 The Author(s). Genes to Cells published by Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.)- Published
- 2025
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30. Transcriptome analysis of gene expression changes upon enzymatic dissociation in skeletal myoblasts.
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Miyawaki-Kuwakado A, Wu Q, Harada A, Tomimatsu K, Fujii T, Maehara K, and Ohkawa Y
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- Animals, Cell Line, Mice, Myoblasts drug effects, NIH 3T3 Cells, RNA-Seq standards, Trypsin pharmacology, Myoblasts metabolism, RNA-Seq methods, Transcriptome
- Abstract
Single-cell RNA-sequencing analysis is one of the most effective tools for understanding specific cellular states. The use of single cells or pooled cells in RNA-seq analysis requires the isolation of cells from a tissue or culture. Although trypsin or more recently cold-active protease (CAP) has been used for cell dissociation, the extent to which the gene expression changes are suppressed has not been clarified. To this end, we conducted detailed profiling of the enzyme-dependent gene expression changes in mouse skeletal muscle progenitor cells, focusing on the enzyme treatment time, amount and temperature. We found that the genes whose expression was changed by the enzyme treatment could be classified in a time-dependent manner and that there were genes whose expression was changed independently of the enzyme treatment time, amount and temperature. This study will be useful as reference data for genes that should be excluded or considered for RNA-seq analysis using enzyme isolation methods., (© 2021 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.)
- Published
- 2021
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31. A study on the association between eye movements and regular mouthing movements (RMMs) in normal fetuses between 24 to 39 weeks of gestation.
- Author
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Maehara K, Morokuma S, Nakahara K, Okawa H, and Kato K
- Subjects
- Female, Humans, Pregnancy, Eye Movements physiology, Fetus physiology, Gestational Age, Mouth physiology
- Abstract
Regular Mouthing Movements (RMMs) are movements in which lips and lower jaw movements occur regularly and can be observed in the fetus using transabdominal ultrasonic tomography. In near term infants, it is known that RMMs form clusters during the quiet sleep period. The notation of RMMs is not uniform, and is described as spontaneous sucking movement or non-nutritive sucking in newborns. Non-nutritive sucking is used to evaluate neurological function after birth, but there are no fetal indicators. The purpose of this study was to clarify the changes in the RMM clusters in fetuses at 24-39 weeks of gestation, and to investigate the relationship with the non-eye movement (NEM) period, which corresponds to the quiet sleep period after birth. Subjects included 83 normal single pregnancy cases. Fetal RMMs and eye movement (EM) were observed for 60 minutes using ultrasonic tomography and recorded as moving image files. We created time series data of eye movements and mouth movements from video recordings, and calculated RMM clusters per minute within effective observation time, RMM clusters per minute in EM period, RMM clusters per minute in NEM period, mouthing movements per cluster and ratio of number of RMM clusters per minute between NEM and EM periods and analyzed using linear regression analysis. As a result, critical points were detected in at two time points, at 32-33 weeks and 36-37 weeks of gestation, in RMM clusters per minute within the effective observation time and RMM clusters per minute in NEM period, respectively. RMM clusters in human fetuses increased from 32-33 to 36-37 weeks. This change is thought to represent fetal sleep development and central nervous system development., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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32. Serum soluble ST2 as a marker of renal scar in pediatric upper urinary tract infection.
- Author
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Ohta N, Yasudo H, Mizutani M, Matsushige T, Fukano R, Kittaka S, Maehara K, Ichihara K, Ohga S, and Hasegawa S
- Subjects
- Biomarkers blood, Child, Child, Preschool, Cytokines blood, Female, Humans, Infant, Male, ROC Curve, Sensitivity and Specificity, Solubility, Interleukin-1 Receptor-Like 1 Protein blood, Kidney pathology, Urinary Tract Infections blood
- Abstract
Background and Objectives: Upper urinary tract infection is the most common serious bacterial infection in childhood. Patients with upper urinary tract infection have a risk for renal scarring with subsequent complications including hypertension, proteinuria, and progressive renal failure. However, the predictive biomarkers of renal scarring in children with upper urinary tract infection are still unknown. In this study, we evaluated whether soluble ST2 levels can be biomarkers of subsequent renal scarring in patients with upper urinary tract infection., Design, Setting, Participants, and Measurements: We retrospectively studied pediatric patients with upper urinary tract infection at a tertiary center. Twenty-eight children had an upper urinary tract infection with (n = 14) and without (n = 14) renal scarring and underwent 99mtechnetium dimercaptosuccinic acid imaging. In addition, 13 control subjects were enrolled. The clinical data and serum cytokine levels, including soluble ST2 levels, were compared between those with and without renal scars., Results: Serum soluble ST2 levels were significantly higher in the scar group than in the non-scar group, whereas there was no difference in the levels of serum interferon-γ, interleukin-6, interleukin-10, soluble tumor necrosis factor receptor 1, and transforming growth factor-β between the scar and non-scar groups. The area under the curve for differentiating between the non-scar and scar groups on the basis of measurements of serum soluble ST2 was 0.79, with a sensitivity and specificity of 92.9% and 64.3%, respectively., Conclusion: These results suggest that serum soluble ST2 levels on admission could be a useful biomarker of subsequent renal scarring in pediatric patients with upper urinary tract infection., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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33. Sensitive detection of fluorescence in western blotting by merging images.
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Kondo Y, Higa S, Iwasaki T, Matsumoto T, Maehara K, Harada A, Baba Y, Fujita M, and Ohkawa Y
- Subjects
- Animals, Blotting, Western statistics & numerical data, Cell Line, Fluorescent Dyes, Glutathione Transferase metabolism, Image Enhancement methods, Luminescent Measurements, Mice, Microscopy, Fluorescence statistics & numerical data, Recombinant Proteins metabolism, Sensitivity and Specificity, Blotting, Western methods, Microscopy, Fluorescence methods
- Abstract
The western blotting technique is widely used to analyze protein expression levels and protein molecular weight. The chemiluminescence method is mainly used for detection due to its high sensitivity and ease of manipulation, but it is unsuitable for detailed analyses because it cannot be used to detect multiple proteins simultaneously. Recently, more attention has been paid to the fluorescence detection method because it is more quantitative and is suitable for the detection of multiple proteins simultaneously. However, fluorescence detection can be limited by poor image resolution and low detection sensitivity. Here, we describe a method to detect fluorescence in western blots using fluorescence microscopy to obtain high-resolution images. In this method, filters and fluorescent dyes are optimized to enhance detection sensitivity to a level similar to that of the chemiluminescence method.
- Published
- 2018
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34. Eye movement activity in normal human fetuses between 24 and 39 weeks of gestation.
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Okawa H, Morokuma S, Maehara K, Arata A, Ohmura Y, Horinouchi T, Konishi Y, and Kato K
- Subjects
- Female, Humans, Pregnancy, Sleep, REM, Ultrasonography, Prenatal, Eye Movements, Fetus physiology, Gestational Age
- Abstract
Rapid eye movement (REM) sleep occurs throughout a relatively large proportion of early development, and normal REM activity appears to be required for healthy brain development. The eye movements (EMs) observed during REM sleep are the most distinctive characteristics of this state. EMs are used as an index of neurological function postnatally, but no specific indices of EM activity exist for fetuses. We aimed to identify and characterize EM activity, particularly EM bursts suggestive of REM periods, in fetuses with a gestational age between 24 and 39 weeks. This cross-sectional study included 84 normal singleton pregnancies. Fetal EMs were monitored using real-time ultrasonography for 60 min and recorded as videos. The videos were manually converted into a time series of EM events, which were then analyzed by piecewise linear regression for various EM characteristics, including EM density, EM burst density, density of EMs in EM bursts, and continuous EM burst time. Two critical points for EM density, EM burst density, and density of EMs in EM bursts were evident at gestation weeks 28-29 and 36-37. Overall EM activity in human fetuses increased until 28-29 weeks of gestation, then again from 36-37 to 38-39 weeks of gestation. These findings may be useful for creating indices of fetal neurological function for prognostic purposes.
- Published
- 2017
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35. Thymine DNA glycosylase modulates DNA damage response and gene expression by base excision repair-dependent and independent mechanisms.
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Nakamura T, Murakami K, Tada H, Uehara Y, Nogami J, Maehara K, Ohkawa Y, Saitoh H, Nishitani H, Ono T, Nishi R, Yokoi M, Sakai W, and Sugasawa K
- Subjects
- Amino Acid Motifs, Cell Line, DNA Damage, Humans, Mutation, Thymine DNA Glycosylase chemistry, Ubiquitin-Protein Ligases metabolism, Ultraviolet Rays, DNA Repair, Thymine DNA Glycosylase metabolism
- Abstract
Thymine DNA glycosylase (TDG) is a base excision repair (BER) enzyme, which is implicated in correction of deamination-induced DNA mismatches, the DNA demethylation process and regulation of gene expression. Because of these pivotal roles associated, it is crucial to elucidate how the TDG functions are appropriately regulated in vivo. Here, we present evidence that the TDG protein undergoes degradation upon various types of DNA damage, including ultraviolet light (UV). The UV-induced degradation of TDG was dependent on proficiency in nucleotide excision repair and on CRL4
CDT 2 -mediated ubiquitination that requires a physical interaction between TDG and DNA polymerase clamp PCNA. Using the Tdg-deficient mouse embryonic fibroblasts, we found that ectopic expression of TDG compromised cellular survival after UV irradiation and repair of UV-induced DNA lesions. These negative effects on cellular UV responses were alleviated by introducing mutations in TDG that impaired its BER function. The expression of TDG induced a large-scale alteration in the gene expression profile independently of its DNA glycosylase activity, whereas a subset of genes was affected by the catalytic activity of TDG. Our results indicate the presence of BER-dependent and BER-independent functions of TDG, which are involved in regulation of cellular DNA damage responses and gene expression patterns., (© 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.)- Published
- 2017
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36. Potential roles of DNA methylation in the initiation and establishment of replicative senescence revealed by array-based methylome and transcriptome analyses.
- Author
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Sakaki M, Ebihara Y, Okamura K, Nakabayashi K, Igarashi A, Matsumoto K, Hata K, Kobayashi Y, and Maehara K
- Subjects
- Cell Line, Cellular Senescence genetics, CpG Islands genetics, Epigenesis, Genetic genetics, Fibroblasts metabolism, Gene Ontology, Humans, Promoter Regions, Genetic genetics, DNA Methylation genetics, Gene Expression Profiling methods
- Abstract
Cellular senescence is classified into two groups: replicative and premature senescence. Gene expression and epigenetic changes are reported to differ between these two groups and cell types. Normal human diploid fibroblast TIG-3 cells have often been used in cellular senescence research; however, their epigenetic profiles are still not fully understood. To elucidate how cellular senescence is epigenetically regulated in TIG-3 cells, we analyzed the gene expression and DNA methylation profiles of three types of senescent cells, namely, replicatively senescent, ras-induced senescent (RIS), and non-permissive temperature-induced senescent SVts8 cells, using gene expression and DNA methylation microarrays. The expression of genes involved in the cell cycle and immune response was commonly either down- or up-regulated in the three types of senescent cells, respectively. The altered DNA methylation patterns were observed in replicatively senescent cells, but not in prematurely senescent cells. Interestingly, hypomethylated CpG sites detected on non-CpG island regions ("open sea") were enriched in immune response-related genes that had non-CpG island promoters. The integrated analysis of gene expression and methylation in replicatively senescent cells demonstrated that differentially expressed 867 genes, including cell cycle- and immune response-related genes, were associated with DNA methylation changes in CpG sites close to the transcription start sites (TSSs). Furthermore, several miRNAs regulated in part through DNA methylation were found to affect the expression of their targeted genes. Taken together, these results indicate that the epigenetic changes of DNA methylation regulate the expression of a certain portion of genes and partly contribute to the introduction and establishment of replicative senescence., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2017
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37. Identification of Immunoglobulin Gene Sequences from a Small Read Number of mRNA-Seq Using Hybridomas.
- Author
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Kuniyoshi Y, Maehara K, Iwasaki T, Hayashi M, Semba Y, Fujita M, Sato Y, Kimura H, Harada A, and Ohkawa Y
- Subjects
- Gene Expression Profiling, Humans, RNA, Messenger genetics, Genes, Immunoglobulin genetics, Hybridomas metabolism, Sequence Analysis, RNA
- Abstract
Identification of immunoglobulin genes in hybridomas is essential for producing antibodies for research and clinical applications. A couple of methods such as RACE and degenerative PCR have been developed for determination of the Igh and Igl/Igk coding sequences (CDSs) but it has been difficult to process a number of hybridomas both with accuracy and rapidness. Here, we propose a new strategy for antibody sequence determination by mRNA-seq of hybridomas. We demonstrated that hybridomas highly expressed the Igh and Igl/Igk genes and that de novo transcriptome assembly using mRNA-seq data enabled identification of the CDS of both Igh and Igl/Igk accurately. Furthermore, we estimated that only 30,000 sequenced reads are required to identify immunoglobulin sequences from four different hybridoma clones. Thus, our approach would facilitate determining variable CDSs drastically., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2016
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38. Regulation of RNA polymerase II activation by histone acetylation in single living cells.
- Author
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Stasevich TJ, Hayashi-Takanaka Y, Sato Y, Maehara K, Ohkawa Y, Sakata-Sogawa K, Tokunaga M, Nagase T, Nozaki N, McNally JG, and Kimura H
- Subjects
- Acetylation, Animals, Cell Line, Tumor, Cell Survival, Chromatin Immunoprecipitation, Enzyme Activation, Genome genetics, Kinetics, Lysine metabolism, Mice, Microscopy, Fluorescence, Phosphorylation, Time Factors, Transcription Elongation, Genetic, Transcription Initiation, Genetic, Histones chemistry, Histones metabolism, RNA Polymerase II metabolism, Single-Cell Analysis, Transcription, Genetic
- Abstract
In eukaryotic cells, post-translational histone modifications have an important role in gene regulation. Starting with early work on histone acetylation, a variety of residue-specific modifications have now been linked to RNA polymerase II (RNAP2) activity, but it remains unclear if these markers are active regulators of transcription or just passive byproducts. This is because studies have traditionally relied on fixed cell populations, meaning temporal resolution is limited to minutes at best, and correlated factors may not actually be present in the same cell at the same time. Complementary approaches are therefore needed to probe the dynamic interplay of histone modifications and RNAP2 with higher temporal resolution in single living cells. Here we address this problem by developing a system to track residue-specific histone modifications and RNAP2 phosphorylation in living cells by fluorescence microscopy. This increases temporal resolution to the tens-of-seconds range. Our single-cell analysis reveals histone H3 lysine-27 acetylation at a gene locus can alter downstream transcription kinetics by as much as 50%, affecting two temporally separate events. First acetylation enhances the search kinetics of transcriptional activators, and later the acetylation accelerates the transition of RNAP2 from initiation to elongation. Signatures of the latter can be found genome-wide using chromatin immunoprecipitation followed by sequencing. We argue that this regulation leads to a robust and potentially tunable transcriptional response.
- Published
- 2014
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39. SraTailor: graphical user interface software for processing and visualizing ChIP-seq data.
- Author
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Oki S, Maehara K, Ohkawa Y, and Meno C
- Subjects
- Sequence Analysis, DNA, Chromatin Immunoprecipitation instrumentation, Electronic Data Processing, Software, User-Computer Interface
- Abstract
Raw data from ChIP-seq (chromatin immunoprecipitation combined with massively parallel DNA sequencing) experiments are deposited in public databases as SRAs (Sequence Read Archives) that are publically available to all researchers. However, to graphically visualize ChIP-seq data of interest, the corresponding SRAs must be downloaded and converted into BigWig format, a process that involves complicated command-line processing. This task requires users to possess skill with script languages and sequence data processing, a requirement that prevents a wide range of biologists from exploiting SRAs. To address these challenges, we developed SraTailor, a GUI (Graphical User Interface) software package that automatically converts an SRA into a BigWig-formatted file. Simplicity of use is one of the most notable features of SraTailor: entering an accession number of an SRA and clicking the mouse are the only steps required to obtain BigWig-formatted files and to graphically visualize the extents of reads at given loci. SraTailor is also able to make peak calls, generate files of other formats, process users' own data, and accept various command-line-like options. Therefore, this software makes ChIP-seq data fully exploitable by a wide range of biologists. SraTailor is freely available at http://www.devbio.med.kyushu-u.ac.jp/sra_tailor/, and runs on both Mac and Windows machines., (© 2014 The Authors Genes to Cells © 2014 by the Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.)
- Published
- 2014
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40. Compilation of copy number variants identified in phenotypically normal and parous Japanese women.
- Author
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Migita O, Maehara K, Kamura H, Miyakoshi K, Tanaka M, Morokuma S, Fukushima K, Shimamoto T, Saito S, Sago H, Nishihama K, Abe K, Nakabayashi K, Umezawa A, Okamura K, and Hata K
- Subjects
- Female, Genetic Association Studies methods, Homozygote, Humans, Japan, Parity, Pregnancy, Sequence Deletion, DNA Copy Number Variations, Phenotype
- Abstract
With increasing public concern about infertility and the frequent involvement of chromosomal anomalies in miscarriage, analyses of copy number variations (CNVs) have been used to identify the genomic regions responsible for each process of childbearing. Although associations between CNVs and diseases have been reported, many CNVs have also been identified in healthy individuals. Like other types of mutations, phenotypically indefinite CNVs may have been retained and accumulated during anthropogenesis. Therefore to distinguish causative variants from other variants is a formidable task. Furthermore, because previous studies have predominantly focused on European and African populations, comprehensive detection of common Asian CNVs is eagerly awaited. Here, using a high-resolution genotyping array and samples from 411 Japanese women with normal parity without significant complications, we have compiled 1043 copy number variable regions. In total, the collected regions cover 164 Mb, or up to 0.5% of the genome. The copy number differences in these regions may be irrelevant not only to infertility but also to a wide range of diseases. The utility of this resource in reducing the candidate pathogenetic variants, especially in Japanese subjects, is also demonstrated.
- Published
- 2014
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41. Allelic asymmetry of the Lethal hybrid rescue (Lhr) gene expression in the hybrid between Drosophila melanogaster and D. simulans: confirmation by using genetic variations of D. melanogaster.
- Author
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Shirata M, Araye Q, Maehara K, Enya S, Takano-Shimizu T, and Sawamura K
- Subjects
- Animals, Crosses, Genetic, Drosophila classification, Female, Gene Expression, Genetic Speciation, Genetic Variation, Genome, Insect, Male, Mutation, Phenotype, X Chromosome, Dosage Compensation, Genetic, Drosophila genetics, Drosophila growth & development, Drosophila Proteins genetics, Drosophila Proteins metabolism
- Abstract
In the cross between Drosophila melanogaster females and D. simulans males, hybrid males die at the late larval stage, and the sibling females also die at later stages at high temperatures. Removing the D. simulans allele of the Lethal hybrid rescue gene (Lhr (sim) ) improves the hybrid incompatibility phenotypes. However, the loss-of-function mutation of Lhr (sim) (Lhr (sim0) ) does not rescue the hybrid males in crosses with several D. melanogaster strains. We first describe the genetic factor possessed by the D. melanogaster strains. It has been suggested that removing the D. melanogaster allele of Lhr (Lhr (mel) ), that is Lhr (mel0) , does not have the hybrid male rescue effect, contrasting to Lhr (sim0) . Because the expression level of the Lhr gene is known to be Lhr (sim) > Lhr (mel) in the hybrid, Lhr (mel0) may not lead to enough of a reduction in total Lhr expression. Then, there is a possibility that the D. melanogaster factor changes the expression level to Lhr (sim) < Lhr (mel) . But in fact, the expression level was Lhr (sim) > Lhr (mel) in the hybrid irrespectively of the presence of the factor. At last, we showed that Lhr (mel0) slightly improves the viability of hybrid females, which was not realized previously. All of the present results are consistent with the allelic asymmetry model of the Lhr gene expression in the hybrid.
- Published
- 2014
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- View/download PDF
42. Introgression of Drosophila simulans nuclear pore protein 160 in Drosophila melanogaster alone does not cause inviability but does cause female sterility.
- Author
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Sawamura K, Maehara K, Mashino S, Kagesawa T, Kajiwara M, Matsuno K, Takahashi A, and Takano-Shimizu T
- Subjects
- Animals, Animals, Genetically Modified, Chromosomes, Insect, Crosses, Genetic, Drosophila physiology, Drosophila Proteins genetics, Drosophila melanogaster physiology, Female, Genes, Lethal, Genetic Engineering, Genetic Markers, Genetic Variation, Genome, Genotype, Heterozygote, Hybridization, Genetic, Infertility, Female genetics, Male, Nuclear Proteins genetics, Phenotype, Polymerase Chain Reaction, Transgenes, Drosophila genetics, Drosophila melanogaster genetics, Genes, Insect, Nuclear Pore Complex Proteins genetics
- Abstract
We have been analyzing genes for reproductive isolation by replacing Drosophila melanogaster genes with homologs from Drosophila simulans by interspecific backcrossing. Among the introgressions established, we found that a segment of the left arm of chromosome 2, Int(2L)S, carried recessive genes for hybrid sterility and inviability. That nuclear pore protein 160 (Nup160) in the introgression region is involved in hybrid inviability, as suggested by others, was confirmed by the present analysis. Male hybrids carrying an X chromosome of D. melanogaster were not rescued by the Lethal hybrid rescue (Lhr) mutation when the D. simulans Nup160 allele was made homozygous or hemizygous. Furthermore, we uniquely found that Nup160 is also responsible for hybrid sterility. Females were sterile when D. simulans Nup160 was made homozygous or hemizygous in the D. melanogaster genetic background. Genetic analyses indicated that the D. simulans Nup160 introgression into D. melanogaster was sufficient to cause female sterility but that other autosomal genes of D. simulans were also necessary to cause lethality. The involvement of Nup160 in hybrid inviability and female sterility was confirmed by transgene experiment.
- Published
- 2010
- Full Text
- View/download PDF
43. High enantioselectivity and broad substrate specificity of a carbonyl reductase: toward a versatile biocatalyst.
- Author
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Ema T, Moriya H, Kofukuda T, Ishida T, Maehara K, Utaka M, and Sakai T
- Subjects
- Catalysis, Magnetic Resonance Spectroscopy, Molecular Conformation, Saccharomyces cerevisiae chemistry, Stereoisomerism, Substrate Specificity, Alcohol Oxidoreductases chemistry
- Published
- 2001
- Full Text
- View/download PDF
44. Benign familial hematuria.
- Author
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Yoshikawa N, Matsuyama S, Iijima K, Maehara K, Okada S, and Matsuo T
- Subjects
- Basement Membrane ultrastructure, Child, Female, Hematuria genetics, Humans, Kidney Glomerulus ultrastructure, Male, Hematuria pathology
- Abstract
Fifty children had benign familial hematuria. They were from 43 families showing neither deafness, heavy proteinuria, nor chronic renal failure and had a nonprogressive course. Light microscopy of renal biopsy specimens showed little or no glomerular changes. Immunofluorescence showed no significant glomerular deposits of immunoglobulins or complement components, but deposition of C3 in the arteriolar walls was observed in 21 of the 39 patients examined. Electron microscopy demonstrated widespread attenuation of the glomerular basement membrane (GBM) in 19 patients, focal attenuation in 22, and normal GBM in nine. These observations suggest that patients with benign familial hematuria are heterogeneous and that the thin GBM may be related to hematuria.
- Published
- 1988
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