23 results on '"Toshiki, Nakamura"'
Search Results
2. Evaluation of large deflection response of circular mesh tubes (2nd report: in case of considering the effect of tube ovalization across the cross-section)
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Toshiki NAKAMURA, Kuniharu USHIJIMA, and Keigo TOKUMARU
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mechanical properties ,structural analysis ,elastic analysis ,flattening ,pure bending ,fem ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
In this paper, the large deflection response of a circular mesh tube under pure bending was investigated by using FE analysis. In the previous study[Nakamura, T., Ushijima, K., Evaluation of large deflection response of circular mesh tubes, Transaction of the JSME (in Japanese), Vol. 88, No. 915 (2022)], the effect of the ovalization across the cross-section on the bending response was neglected, but in this study, the influence of cross-sectional flattening on the nonlinear bending moment versus curvature was taken into consideration. There are three reasons for arising the maximum bending moment, but in this paper, we mainly focused on the two mechanisms (the large flattening response in elastic deformation and the plastic yielding behaviour) to the maximum bending moment. Based on our FE analysis, we proposed theoretical equations for predicting the maximum bending moment as a function of tube geometries and material parameters such as Poisson’s ratio and the plastic yielding stress.
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- 2023
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3. Effects of wearing surgical masks on fraction of inspired oxygen in spontaneously breathing patients: improving safety for frontline healthcare professionals under pandemic situations
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Kazuhiro Minoguchi, Akira Isii, Toshiki Nakamura, Hitoshi Sato, Takeru Abe, Hiromasa Kawakami, Kyota Nakamura, and Takahisa Goto
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COVID-19 ,Fraction of inspired oxygen ,Oxygen mask ,Respiratory infections ,Surgical mask ,Preventing infection ,Anesthesiology ,RD78.3-87.3 - Abstract
Abstract Background During pandemic situations, many guidelines recommend that surgical masks be worn by both healthcare professionals and infected patients in healthcare settings. The purpose of this study was to clarify the levels and changes of oxygen concentration over time while oxygen was administered over a surgical mask. Methods Patients scheduled to undergo general anesthesia (n = 99) were enrolled in this study. First, patients were administered oxygen at 6 L/min via an oxygen mask over a surgical mask for 5 min. The patients removed the surgical mask and then took a 3-min break; thereafter, the same amount of oxygen was administered for another 5 min via the oxygen mask. We measured the fraction of inspired oxygen (FiO2), the end-tidal CO2 (EtCO2), and respiratory frequency every minute for 5 min, both while administering oxygen with and without a surgical mask. The FiO2 was measured at the beginning of inspiration and the EtCO2 was measured at the end of expiration. Results The FiO2 at 5 min was significantly lower when breathing with a surgical mask than that without it (mean difference: 0.08 [95% CI: 0.067–0.10]; p
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- 2022
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4. Evaluation of large deflection response of circular mesh tubes (1st report: without considering the effect of the ovalization)
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Toshiki NAKAMURA and Kuniharu USHIJIMA
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mesh structure ,mechanical properties ,structural analysis ,circular tube ,fem ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
In this paper, the large deflection of a circular mesh tube was investigated by using a finite element method. During this investigation, it is assumed that the tube is deformed elastically, and its structural nonlinearity due to large deflection was considered. In addition, a theoretical model of an arc-shaped beam is proposed in order to predict the equivalent stiffness. The equivalent stiffness can be used to estimate the nonlinear large deflection response of the tube. In particular, the effects of the number of spirals and the number of turns on the prediction accuracy was discussed.
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- 2022
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5. Sudden onset of sleep caused by hypothalamic infarction: a case report
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Takeo Matsubara, Keisuke Suzuki, Akiko Kawasaki, Masayuki Miyamoto, Madoka Okamura, Takashi Kanbayashi, Hidehiro Takekawa, Toshiki Nakamura, Yuji Watanabe, Masanori Matsubara, and Koichi Hirata
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Hypothalamic infarction ,Sudden onset of sleep ,Hypersomnia ,Horner syndrome ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Hypothalamic lesions, such as tumors and demyelinating diseases, reportedly cause abnormal sleepiness. However, stroke involving the hypothalamus has rarely been described. Here, we report a patient with infarction restricted to the hypothalamus who presented with sudden onset of sleep. Case presentation A 42-year-old woman with a history of migraine without aura presented with irresistible sleepiness and developed several episodes of sudden onset of sleep. Neurological examinations were unremarkable except for partial left Horner syndrome. Brain magnetic resonance imaging (MRI) revealed a high-intensity lesion restricted to the left hypothalamus on diffusion-weighted and fluid-attenuated inversion recovery MRI images. Cerebrospinal fluid (CSF) orexin-A levels obtained on hospital day 3 after her sleepiness had resolved were normal (337 pg/mL; normal > 200 pg/mL). Serum anti-nuclear and anti-aquaporin 4 (AQP4) antibodies and CSF myelin basic protein and oligoclonal band were negative. A small hypothalamic infarction was suspected, and the patient was treated with intravenous edaravone and argatroban, as well as oral clopidogrel. Three months later, there had been no clinical relapse, and the hypothalamic lesion had almost disappeared on follow-up MRI. No new lesion suggestive of demyelinating disease or tumor was observed. Conclusion Hypothalamic stroke should be considered a cause of sudden onset of sleep.
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- 2019
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6. Perspectives on Low Temperature Tolerance and Vernalization Sensitivity in Barley: Prospects for Facultative Growth Habit
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María Muñoz-Amatriaín, Javier Hernandez, Dustin Herb, P. Stephen Baenziger, Anne Marie Bochard, Flavio Capettini, Ana Casas, Alfonso Cuesta-Marcos, Claus Einfeldt, Scott Fisk, Amelie Genty, Laura Helgerson, Markus Herz, Gongshe Hu, Ernesto Igartua, Ildiko Karsai, Toshiki Nakamura, Kazuhiro Sato, Kevin Smith, Eric Stockinger, William Thomas, and Patrick Hayes
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barley ,low temperature tolerance ,GWAS ,meta-analysis ,facultative ,multi-environments ,Plant culture ,SB1-1110 - Abstract
One option to achieving greater resiliency for barley production in the face of climate change is to explore the potential of winter and facultative growth habits: for both types, low temperature tolerance (LTT) and vernalization sensitivity are key traits. Sensitivity to short-day photoperiod is a desirable attribute for facultative types. In order to broaden our understanding of the genetics of these phenotypes, we mapped quantitative trait loci (QTLs) and identified candidate genes using a genome-wide association studies (GWAS) panel composed of 882 barley accessions that was genotyped with the Illumina 9K single-nucleotide polymorphism (SNP) chip. Fifteen loci including 5 known and 10 novel QTL/genes were identified for LTT—assessed as winter survival in 10 field tests and mapped using a GWAS meta-analysis. FR-H1, FR-H2, and FR-H3 were major drivers of LTT, and candidate genes were identified for FR-H3. The principal determinants of vernalization sensitivity were VRN-H1, VRN-H2, and PPD-H1. VRN-H2 deletions conferred insensitive or intermediate sensitivity to vernalization. A subset of accessions with maximum LTT were identified as a resource for allele mining and further characterization. Facultative types comprised a small portion of the GWAS panel but may be useful for developing germplasm with this growth habit.
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- 2020
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7. Formulation of tactile Gestalt to express variation in velvet hand illusion caused by out-of-phase cycles of two wires
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Hiraku KOMURA, Toshiki NAKAMURA, and Masahiro OHKA
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actuator system ,virtual reality ,velvet hand illusion ,tactile gestalt ,formulation ,Engineering machinery, tools, and implements ,TA213-215 ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
To develop a tactile display, we focused on the Velvet Hand Illusion (VHI), which is a tactile illusion phenomenon. The most important feature of VHI is that VHI is not generated in one wire but is generated in two or more wires. This means that we recognize the area surrounded by wires as a Gestalt and a smooth surface sensation is generated in the Gestalt. We assume that the VHI mechanism is related to the law of closure and the law of common fate in Gestalt theory. In this paper, we investigate the relationship between VHI and the law of closure by means of variation in a phase difference of two wires’ cyclic movement, and formulate VHI variation, taking into account the law of closure. We try to divide the law of closure into two factors: one of them is a factor of translation and the other is a factor of elasticity. We formulate the tactile Gestalt and verify the validity of this formulation by comparing the result of the psychophysical experiment to the estimation via the formulation. This work shows that the law of closure in the tactile Gestalt consists of the translation factor and the elasticity factor, and the VHI mechanism is described by the formulation of the tactile Gestalt.
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- 2020
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8. Multifamily QTL analysis and comprehensive design of genotypes for high-quality soft wheat.
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Goro Ishikawa, Takeshi Hayashi, Kazuhiro Nakamura, Tsuyoshi Tanaka, Fuminori Kobayashi, Mika Saito, Hiroyuki Ito, Sachiko Ikenaga, Yoshinori Taniguchi, and Toshiki Nakamura
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Medicine ,Science - Abstract
Milling properties and flour color are essential selection criteria in soft wheat breeding. However, high phenotypic screening costs restrict selection to relatively few breeding lines in late generations. To achieve marker-based selection of these traits in early generations, we performed genetic dissection of quality traits using three doubled haploid populations that shared the high-quality soft wheat variety Kitahonami as the paternal parent. An amplicon sequencing approach allowed effective construction of well-saturated linkage maps of the populations. Marker-based heritability estimates revealed that target quality traits had relatively high values, indicating the possibility of selection in early generations. Taking advantage of Chinese Spring reference sequences, joint linkage maps of the three populations were generated. Based on the maps, multifamily quantitative trait locus (QTL) analysis revealed a total of 86 QTLs for ten traits investigated. In terms of target quality traits, 12 QTLs were detected for flour yield, and 12 were detected for flour redness (a* value). Among these QTLs, six for flour yield and nine for flour a* were segregating in more than two populations. Some relationships among traits were explained by QTL collocations on chromosomes, especially group 7 chromosomes. Ten different ideotypes with various combinations of favorable alleles for the flour yield and flour a* QTLs were generated. Phenotypes of derivatives from these ideotypes were predicted to design ideal genotypes for high-quality wheat. Simulations revealed the possibility of breeding varieties with better quality than Kitahonami.
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- 2020
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9. Investigation of Tactile Illusion Based on Gestalt Theory
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Hiraku Komura, Toshiki Nakamura, and Masahiro Ohka
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tactileology ,tactile gestalt ,principle of prägnanz ,law of closure ,formulation ,psychophysics ,Logic ,BC1-199 ,Philosophy (General) ,B1-5802 - Abstract
Time-evolving tactile sensations are important in communication between animals as well as humans. In recent years, this research area has been defined as “tactileology,” and various studies have been conducted. This study utilized the tactile Gestalt theory to investigate these sensations. Since humans recognize shapes with their visual sense and melodies with their auditory sense based on the Prägnanz principle in the Gestalt theory, this study assumed that a time-evolving texture sensation is induced by a tactile Gestalt. Therefore, the operation of such a tactile Gestalt was investigated. Two psychophysical experiments were conducted to clarify the operation of a tactile Gestalt using a tactile illusion phenomenon called the velvet hand illusion (VHI). It was confirmed that the VHI is induced in a tactile Gestalt when the laws of closure and common fate are satisfied. Furthermore, it was clarified that the tactile Gestalt could be formulated using the proposed factors, which included the laws of elasticity and translation, and it had the same properties as a visual Gestalt. For example, the strongest Gestalt factor had the highest priority among multiple competing factors.
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- 2021
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10. Ischemic Stroke as the Initial Manifestation of Neurosyphilis in a Young Adult Patient Positive for Human Immunodeficiency Virus
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Ayaka Numao, Keisuke Suzuki, Hidehiro Takekawa, Toshiki Nakamura, Hisatake Iwanami, Naoki Izawa, Akio Iwasaki, Hiroaki Fujita, Yuji Watanabe, and Koichi Hirata
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Neurosyphilis, human immunodeficiency virus, young adult, initial symptom ,Medicine - Abstract
A 31-year-old man with pontine infarction was referred to our hospital for further evaluation and treatment. At admission, his neurological examination was unremarkable. No lymphadenopathy or skin lesions were found. The Treponema pallidum haemagglutination test, rapid plasma regain test and fluorescent treponemal antibody absorption test of immunoglobulin G were positive in both serum and cerebrospinal fluid (CSF). CSF analysis showed lymphocytic pleocytosis. The patient had male-to-male sexual contact and was found to be HIV positive. Physicians should be aware that acute ischaemic stroke may be the first manifestation of neurosyphilis in a young adult, especially with HIV infection.
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- 2014
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11. Association mapping and validation of QTLs for flour yield in the soft winter wheat variety Kitahonami.
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Goro Ishikawa, Kazuhiro Nakamura, Hiroyuki Ito, Mika Saito, Mikako Sato, Hironobu Jinno, Yasuhiro Yoshimura, Tsutomu Nishimura, Hidekazu Maejima, Yasushi Uehara, Fuminori Kobayashi, and Toshiki Nakamura
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Medicine ,Science - Abstract
The winter wheat variety Kitahonami shows a superior flour yield in comparison to other Japanese soft wheat varieties. To map the quantitative trait loci (QTL) associated with this trait, association mapping was performed using a panel of lines from Kitahonami's pedigree, along with leading Japanese varieties and advanced breeding lines. Using a mixed linear model corrected for kernel types and familial relatedness, 62 marker-trait associations for flour yield were identified and classified into 21 QTLs. In eighteen of these, Kitahonami alleles showed positive effects. Pedigree analysis demonstrated that a continuous pyramiding of QTLs had occurred throughout the breeding history of Kitahonami. Linkage analyses using three sets of doubled haploid populations from crosses in which Kitahonami was used as a parent were performed, leading to the validation of five of the eight QTLs tested. Among these, QTLs on chromosomes 3B and 7A showed highly significant and consistent effects across the three populations. This study shows that pedigree-based association mapping using breeding materials can be a useful method for QTL identification at the early stages of breeding programs.
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- 2014
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12. Plasticizers May Activate Human Hepatic Peroxisome Proliferator-Activated Receptor α Less Than That of a Mouse but May Activate Constitutive Androstane Receptor in Liver
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Yuki Ito, Toshiki Nakamura, Yukie Yanagiba, Doni Hikmat Ramdhan, Nozomi Yamagishi, Hisao Naito, Michihiro Kamijima, Frank J. Gonzalez, and Tamie Nakajima
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Biology (General) ,QH301-705.5 - Abstract
Dibutylphthalate (DBP), di(2-ethylhexyl)phthalate (DEHP), and di(2-ethylhexyl)adipate (DEHA) are used as plasticizers. Their metabolites activate peroxisome proliferator-activated receptor (PPAR) α, which may be related to their toxicities. However, species differences in the receptor functions between rodents and human make it difficult to precisely extrapolate their toxicity from animal studies to human. In this paper, we compared the species differences in the activation of mouse and human hepatic PPARα by these plasticizers using wild-type (mPPARα) and humanized PPARα (hPPARα) mice. At 12 weeks old, each genotyped male mouse was classified into three groups, and fed daily for 2 weeks per os with corn oil (vehicle control), 2.5 or 5.0 mmol/kg DBP (696, 1392 mg/kg), DEHP (977, 1953 mg/kg), and DEHA (926, 1853 mg/kg), respectively. Generally, hepatic PPARα of mPPARα mice was more strongly activated than that of hPPARα mice when several target genes involving β-oxidation of fatty acids were evaluated. Interestingly, all plasticizers also activated hepatic constitutive androstane receptor (CAR) more in hPPARα mice than in mPPARα mice. Taken together, these plasticizers activated mouse and human hepatic PPARα as well as CAR. The activation of PPARα was stronger in mPPARα mice than in hPPARα mice, while the opposite was true of CAR.
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- 2012
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13. Development of Rapid Debinding Treatment Using Superheated Steam and Debinding Behavior for Alumina Molded Bodies.
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Toshiki NAKAMURA, Masashi WADA, Kazumi HAYASHI, Satoshi KITAOKA, Takahiro NAGAI, Jin YANO, Norio MUTO, and Atsusi NAKAHIRA
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SUPERHEATED steam ,EXOTHERMIC reactions ,ALUMINUM oxide ,GAS analysis ,GAS chromatography ,THERMAL analysis ,PYROLYSIS - Abstract
In this study, rapid debinding of alumina molded bodies was carried out using superheated steam treatment. The superheated steam treatment was performed with a temperature increase of 10°C/min to a holding temperature range of 500°C to 800°C. The molded body after superheated steam treatment to 800°C resulted in a carbon removal rate of 99.3%. No cracking occurred in sintered bodies obtained by debinding in superheated steam and then firing at 1,600°C in air. However, many large cracks occurred in sintered bodies that had been treated in air under similar temperature conditions. Thus, it was suggested that superheated steam treatment is highly effective for rapid debinding of molded bodies. To understand the debinding behavior under superheated steam, thermal analyses were performed with thermogravimetric and differential scanning calorimetric analysis and gas chromatography in humidified atmospheres. These results suggested that the debinding in superheated steam suppressed thermal runaway and the generation of pyrolysis gas caused by the chain of exothermic reactions derived from the oxidation of the forming aid (binder). [ABSTRACT FROM AUTHOR]
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- 2019
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14. An efficient approach for the development of genome-specificmarkers in allohexaploidwheat (Triticumaestivum L.) and its application in the construction of high-density linkagemaps of the D genome.
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Goro Ishikawa, Mika Saito, Tsuyoshi Tanaka, Yuichi Katayose, Hiroyuki Kanamori, Kanako Kurita, and Toshiki Nakamura
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In common wheat, the development of genotyping platforms has been hampered by the large size of the genome, its highly repetitive elements and its allohexaploid nature. However, recent advances in sequencing technology provide opportunities to resolve these difficulties. Using next-generation sequencing and gene-targeting sequence capture, 12,551 nucleotide polymorphisms were detected in the common wheat varieties 'Hatsumochi' and 'Kitahonami' and were assigned to chromosome arms using International Wheat Genome Sequencing Consortium survey sequences. Because the number of markers for D genome chromosomes in commercially available wheat single nucleotide polymorphism arrays is insufficient, we developed markers using a genome-specific amplicon sequencing strategy. Approximately 80% of the designed primers successfully amplified D genome-specific products, suggesting that by concentrating on a specific subgenome, we were able to design successful markers as efficiently as could be done in a diploid species. The newly developed markers were uniformly distributed across the D genome and greatly extended the total coverage. Polymorphisms were surveyed in six varieties, and 31,542 polymorphic sites and 5,986 potential marker sites were detected in the D genome. The marker development and genotyping strategies are cost effective, robust and flexible and may enhance multi-sample studies in the post-genomic era in wheat. [ABSTRACT FROM AUTHOR]
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- 2018
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15. Effects of Cadmium Treatment on the Uptake and Translocation of Sulfate in Arabidopsis thaliana.
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Chisato Yamaguchi, Yuki Takimoto, Naoko Ohkama-Ohtsu, Akiko Hokura, Takuro Shinano, Toshiki Nakamura, Akiko Suyama, and Akiko Maruyama-Nakashita
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ARABIDOPSIS thaliana ,EFFECT of cadmium on plants ,EFFECT of sulfates on plants ,GLUTATHIONE ,PHYTOCHELATINS - Abstract
Cadmium (Cd) is a highly toxic and non-essential element for plants, whereas phytochelatins and glutathione are lowmolecular- weight sulfur compounds that function as chelators and play important roles in detoxification. Cadmium exposure is known to induce the expression of sulfurassimilating enzymes and sulfate uptake by roots. However, the molecular mechanism underlying Cd-induced changes remains largely unknown. Accordingly, we analyzed the effects of Cd treatment on the uptake and translocation of sulfate and accumulation of thiols in Arabidopsis thaliana. Both wild type (WT) and null mutant (sel1-10 and sel1-18) plants of the sulfate transporter SULTR1;2 exhibited growth inhibition when treated with CdCl
2 . However, the mutant plants exhibited a lower growth rate and lower Cd accumulation. Cadmium treatment also upregulated the transcription of SULTR1;2 and sulfate uptake activity in WT plants, but not in mutant plants. In addition, the sulfate, phytochelatin and total sulfur contents were preferentially accumulated in the shoots of both WT and mutant plants treated with CdCl2 , and sulfur K-edge XANES spectra suggested that sulfate was the main compound responsible for the increased sulfur content in the shoots of CdCl2 -treated plants. Our results demonstrate that Cd-induced sulfate uptake depends on SULTR1;2 activity, and that CdCl2 treatment greatly shifts the distribution of sulfate to shoots, increases the sulfate concentration of xylem sap and upregulates the expression of SULTRs involved in root-toshoot sulfate transport. Therefore, we conclude that root-toshoot sulfate transport is stimulated by Cd and suggest that the uptake and translocation of sulfate in CdCl2 -treated plants are enhanced by demand-driven regulatory networks. [ABSTRACT FROM AUTHOR]- Published
- 2016
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16. Using the Hexaploid Nature of Wheat To Create Variability in Starch Characteristics.
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Takayuki Inokuma, Patricia Vrinten, Tomoya Shimbata, Ai Sunohara, Hiroyuki Ito, Mika Saito, Yoshinori Taniguchi, and Toshiki Nakamura
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- 2016
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17. Genetic Mapping of Major-Effect Seed Dormancy Quantitative Trait Loci on Chromosome 2B using Recombinant Substitution Lines in Tetraploid Wheat.
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Shiaoman Chao, Elias, Elias, Benscher, David, Goro Ishikawa, Yung-Fen Huang, Saito, Mika, Toshiki Nakamura, Steven Xu, Faris, Justin, and Sorrells, Mark
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DURUM wheat ,GERMINATION ,SINGLE nucleotide polymorphisms ,SEED dormancy ,DORMANCY in plants ,EMMER wheat - Abstract
Durum wheat (Triticum turgidum L.) cultivars can benefit from having some level of seed dormancy to help reduce seed damage and lower grain quality caused by preharvest sprouting (PHS) occurring during wet harvesting conditions. Previously, a single chromosome substitution line carrying chromosome 2B of wild emmer [Triticum turgidum L. subsp. dicoccoides (Körn. ex Asch. & Graebn.) Thell.] in the durum cultivar Langdon background was found to have higher levels of seed dormancy and PHS tolerance. In this study, a population of recombinant substitution lines was developed and used to construct a single nucleotide polymorphism (SNP)-based high-density genetic linkage map. Seed germination tests were used to evaluate seed dormancy levels. Multiple interval mapping analysis revealed four quantitative trait loci (QTL) regions affecting seed dormancy. Two regions containing major-effect QTL contributed by wild emmer were consistently expressed in four environments and explained 5.89 to 11.14% of the phenotypic variation. One QTL region was located near the centromere and the other on the long arm of chromosome 2B in Bayes credible intervals of 4 and 7 cM, respectively. Recombinant inbred lines (RILs) carrying both QTL had an average of 35% reduced rate of germination measured by weighted germination index compared with RILs carrying neither QTL. The two QTL regions identified in this study should be useful for improving PHS tolerance in wheat. Efforts to transfer the two QTL into elite durum cultivars are in progress to examine the effects of genetic background and environment on QTL expression and to evaluate the performance of other agronomic traits in the presence of the QTL. [ABSTRACT FROM AUTHOR]
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- 2016
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18. Co-occurrence of multiple cerebral infarctions due to hypercoagulability associated with malignancy and meningeal carcinomatosis as the initial manifestation of gastric cancer.
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Akiko Kawasaki, Keisuke Suzuki, Hidehiro Takekawa, Toshiki Nakamura, Masanari Yamamoto, Yohei Asakawa, Madoka Okamura, and Koichi Hirata
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CEREBRAL infarction ,STOMACH cancer ,CARCINOMA ,CEREBROSPINAL fluid ,FEVER - Abstract
Background Meningeal carcinomatosis and hypercoagulability associated with malignancy are typical late stage complications in cancer patients. The co-occurrence of meningeal carcinomatosis and cerebral infarction related to hypercoagulability associated with malignancy in an individual as the initial manifestation of malignancy has not been previously reported.Case presentation Herein, we report the case of an 80-year-old patient who presented with meningeal carcinomatosis and hypercoagulability related to malignancy as the initial manifestation of occult gastric cancer. The patient displayed consciousness disturbance, mild left facial paralysis, and bilateral positive Babinski's sign. Using brain magnetic resonance imaging, the patient was diagnosed as having acute multiple cerebral infarctions. Cerebrospinal fluid (CSF) cytology showed adenocarcinoma and upper gastrointestinal endoscopy disclosed scirrhous gastric cancer. The patient presented with headache, fever, and meningeal irritation with a subacute course. Tuberculous or fungal meningitis was initially suspected; however, cytological evidence of adenocarcinoma in the CSF led to the diagnosis of meningeal carcinomatosis. Conclusion The comorbidity of hypercoagulability associated with malignancy and meningeal carcinomatosis should be considered in a patient presenting with multiple cerebral infarctions, progressive disturbance of consciousness, fever, and meningeal irritation. [ABSTRACT FROM AUTHOR]
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- 2014
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19. Hypothermia, Hypotension, Hypersomnia, and Obesity Associated With Hypothalamic Lesions in a Patient Positive for the Anti-aquaporin 4 Antibody.
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Keisuke Suzuki, Toshiki Nakamura, Kenichi Hashimoto, Masayuki Miyamoto, Tomoko Komagamine, Takahide Nagashima, Naoki Izawa, Takashi Kanbayashi, Toshiyuki Takahashi, and Koichi Hirata
- Abstract
Objective: To describe a patient positive for the anti-aquaporin 4 antibody with hypothalamic lesions showing hypothermia, hypotension, hypersomnia, and obesity. Design: Case report. Setting: University hospital. Patient: Wedescribe a 21-year-old woman who was positive for anti-aquaporin 4 antibody and presented with hypothermia, hypotension, and hypersomnia owing to bilateral hypothalamic lesions as the only abnormal clinical finding. Results: Immediate steroid administration resulted in significant improvement of the patient's vital signs and imaging findings; however, her cognitive impairment and sleepiness persisted, and she subsequently developed obesity. Decreased cerebrospinal fluid orexin levels and sleep studies confirmed the diagnosis of narcolepsy due to medical condition. Physicians should be aware that neuromyelitis optica spectrum disorders can initially involve the hypothalamus. Conclusions: We emphasize that measurement of anti-aquaporin 4 antibody is of clinical importance in the differential diagnosis of hypothalamic lesions. [ABSTRACT FROM AUTHOR]
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- 2012
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20. Analysis of wheat- Thinopyrum intermedium derivatives with BYDV-resistance.
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Zhi-Shan Lin, Zhi-Fu Cui, Xiang-Yan Zeng, You-Zhi Ma, Zeng-Yan Zhang, Toshiki Nakamura, Goro Ishikawa, Kazuhiro Nakamura, Hisashi Yoshida, and Zhi-Yong Xin
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WHEAT ,PLANT chromosomes ,CYTOGENETICS ,IN situ hybridization ,CULTIVARS ,CROP science - Abstract
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat- Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452 were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was a double ditelosomic line with the mitotic chromosome number of 2 n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably 2Ai-2S telosomes with BYDV-resistance. These wheat- Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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21. Comparative study of the expression profiles of the Cor/Lea gene family in two wheat cultivars with contrasting levels of freezing tolerance.
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Fuminori Kobayashi, Shigeo Takumi, Mineyo Nakata, Ryoko Ohno, Toshiki Nakamura, and Chiharu Nakamura
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GENE expression ,WHEAT ,CULTIVARS ,ACCLIMATIZATION ,BIOCOMPATIBILITY ,PLANT clones - Abstract
Expression profiles of a set of Cor/Lea genes were assessed during early stages of cold acclimation in seedlings of two wheat cultivars, which showed contrasting levels of freezing tolerance. These Cor/Lea family members consisted of three EST clones and 13 previously identified cDNA clones of wheat and rye. Northern blot analysis using RNA extracted from seedling leaves and roots showed that most of the genes exhibited a quite similar time-course of expression, although with different expression levels: They rapidly responded to low temperature and their transcript levels reached high plateaus within 3–5 days. The overall gene expression profiles were correlated with the time-dependent development and the level of freezing tolerance under low temperature in the two cultivars. Western blot analysis of protein accumulation further verified this observation. Abscissic acid response was proved for at least four genes. Light was stimulatory to most of the genes, and this positive light response associated with low temperature occurred not only in leaf-specific genes but also in leaf/root-expressed genes. Taken together, the present results suggest that the Cor/ Lea gene family represents a major group of downstream genes involved in the ABA-dependent and -independent signal pathways and that most of them are co-regulated in determining freezing tolerance in wheat seedlings. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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22. Analysis of the Cooperative ATPase Cycle of the AAA+ Chaperone ClpB from Thermus thermophilus by Using Ordered Heterohexamers with an Alternating Subunit Arrangement.
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Takashi Yamasaki, Yukiko Oohata, Toshiki Nakamura, and Yo-hei Watanabe
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ADENOSINE triphosphatase , *MOLECULAR chaperones , *THERMUS thermophilus , *HYDROLYSIS , *PROTEIN research - Abstract
The ClpB/Hsp104 chaperone solubilizes and reactivates protein aggregates in cooperation with DnaK/Hsp70 and its cofactors. The ClpB/Hsp104 protomer has two AAA+ modules, AAA-1 and AAA-2, and forms a homohexamer. In the hexamer, these modules form a two-tiered ring in which each tier consists of homotypic AAA+ modules. By ATP binding and its hydrolysis at these AAA+ modules, ClpB/Hsp104 exerts the mechanical power required for protein disaggregation. Although ATPase cycle of this chaperone has been studied by several groups, an integrated understanding of this cycle has not been obtained because of the complexity of the mechanism and differences between species. To improve our understanding of the ATPase cycle, we prepared many ordered heterohexamers of ClpB from Thermus thermophilus, in which two subunits having different mutations were cross-linked to each other and arranged alternately and measured their nucleotide binding, ATP hydrolysis, and disaggregation abilities. The results indicated that the ATPase cycle of ClpB proceeded as follows: (i) the 12 AAA+ modules randomly bound ATP, (ii) the binding of four or more ATP to one AAA+ring was sensed by a conserved Arg residue and converted another AAA+ ring into the ATPase-active form, and (iii) ATP hydrolysis occurred cooperatively in each ring. We also found that cooperative ATP hydrolysis in at least one ring was needed for the disaggregation activity of ClpB. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
23. Novel quantitative trait loci for low grain cadmium concentration in common wheat (Triticum aestivum L.).
- Author
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Yusuke Ban, Goro Ishikawa, Hiroaki Ueda, Naoyuki Ishikawa, Keita Kato, Kanenori Takata, Minoru Matsuyama, Hirokazu Handa, Toshiki Nakamura, and Mikiko Yanaka
- Subjects
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GRAIN , *WHEAT , *CEREALS as food , *DURUM wheat , *CADMIUM , *WHEAT breeding - Abstract
Cadmium (Cd) is as an extremely toxic metal that can contaminate agricultural soils. To reduce the risk of Cd intake in food cereals, the development of cultivars with low grain Cd concentration (GCC) is an effective countermeasure. We analyzed quantitative trait loci (QTLs) for GCC in a doubled haploid (DH) common wheat (Triticum aestivum L.) population derived from 'Chugoku 165' (low GCC) × 'Chukei 10-22' (high GCC). We found novel loci for low GCC on the short arm of chromosome 4B and on the long arm of chromosome 6B. These QTLs accounted for 9.4%-25.4% (4B) and 9.0%-17.8% (6B) of the phenotypic variance in the DH population. An association analysis with 43 cultivars identified 3 loci at these QTLs: QCdc.4Bkita, QCdc.6B-kita1, and QCdc.6B-kita2. In contrast to durum wheat and barley, no QTL was detected on the chromosomes of homeologous group 5 for heavy metal P1B-type ATPase 3. These results will contribute to marker-assisted selection for low GCC in breeding of common wheat. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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