93 results on '"Tomohiro, Takayama"'
Search Results
2. Evidence for strong electron correlations in a nonsymmorphic Dirac semimetal
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Yu-Te Hsu, Danil Prishchenko, Maarten Berben, Matija Čulo, Steffen Wiedmann, Emily C. Hunter, Paul Tinnemans, Tomohiro Takayama, Vladimir Mazurenko, Nigel E. Hussey, and Robin S. Perry
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Atomic physics. Constitution and properties of matter ,QC170-197 - Abstract
Abstract Metallic iridium oxides (iridates) provide a fertile playground to explore new phenomena resulting from the interplay between topological protection, spin-orbit and electron-electron interactions. To date, however, few studies of the low energy electronic excitations exist due to the difficulty in synthesising crystals with sufficiently large carrier mean-free-paths. Here, we report the observation of Shubnikov-de Haas quantum oscillations in high-quality single crystals of monoclinic SrIrO3 in magnetic fields up to 35 T. Analysis of the oscillations reveals a Fermi surface comprising multiple small pockets with effective masses up to 4.5 times larger than the calculated band mass. Ab-initio calculations reveal robust linear band-crossings at the Brillouin zone boundary, due to its non-symmorphic symmetry, and overall we find good agreement between the angular dependence of the oscillations and the theoretical expectations. Further evidence of strong electron correlations is realized through the observation of signatures of non-Fermi liquid transport as well as a large Kadowaki-Woods ratio. These collective findings, coupled with knowledge of the evolution of the electronic state across the Ruddlesden-Popper iridate series, establishes monoclinic SrIrO3 as a topological semimetal on the boundary of the Mott metal-insulator transition.
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- 2021
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3. Limiting antibiotic prophylaxis in the treatment of maxillofacial fractures: A retrospective, single-center study of 81 patients
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Kaoru Murakami, Koji Yamamura, Chikashi Minemura, Tomohiro Takayama, Yasushi Kimura, and Hidetaka Yokoe
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Antibiotic prophylaxis ,Maxillofacial fractures ,Open reduction ,Internal fixation ,Internal medicine ,RC31-1245 ,Surgery ,RD1-811 - Abstract
Introduction: The aim of this study was to investigate the validity of the duration for which we provide antibiotic prophylaxis to maxillofacial fracture patients who undergo open reduction and internal fixation (ORIF) in our hospital by retrospectively reviewing the incidence of surgical site infections (SSIs). Methods: The medical records of 83 patients with maxillofacial fractures who underwent ORIF from April 2010 to October 2019 were retrospectively reviewed. The surgeon selected the proper surgical approach to the fracture site depending on the location and type of fractures. ORIF was performed by an intraoral, extraoral, or transconjunctival approach, or a combination of these approaches. No statistical investigation of differences in the method of prophylactic antibiotic administration and the occurrence of SSIs was conducted because of the small sample size. Results: This retrospective study included 81 patients (58 males; median age 41 (range: 13–82) years; median BMI 22.4 (range: 16.5–33.6) kg/m2) with maxillofacial fractures. Two patients with infected fractures before operation withdrew from this study. The most common choice of antibiotic prophylaxis was cefmetazole for 2 days, followed by cefmetazole for 1 day. Two patients were diagnosed with an SSI; one was on cefazolin 2 g for 2 days, and the other was on cefmetazole 2–4 g for 2 days. In both cases the infection was successfully controlled, and implant removal was not required. Conclusions: In principle, antibiotic prophylaxis for 2 days postoperatively is sufficient in ORIF for maxillofacial fracture, but a multicenter, prospective, randomized study may be required to confirm this.
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- 2021
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4. Use of ATP bioluminescence to survey the contamination of dental goggles in surgical removal of impacted mandibular third molars
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Kaoru Murakami, Chikashi Minemura, Koji Yamamura, Tomohiro Takayama, Yasushi Kimura, and Hidetaka Yokoe
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ATP bioluminescence ,Dental goggles ,Mandibular third molars ,Dental surgery ,Infection control ,Internal medicine ,RC31-1245 ,Surgery ,RD1-811 - Abstract
The importance of protecting the eyes from infectious agents in patients’ blood and saliva during dental surgery has long been known, but the global COVID-19 pandemic has made this even more important. The use of ATP bioluminescence to investigate the contamination of dental goggles during the surgical removal of impacted teeth in the present study indicates their importance for protecting the eyes from aerosols from the front, from above, and from the sides.
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- 2021
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5. Identity of the numerous bloodstains at the murder scene: molecular identification of fly artifacts and fly species by CO1 analysis
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Tomohiro, Takayama, Rie, Takai, Kanae, Kita, and Yuji, Sakai
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Pathology and Forensic Medicine - Abstract
Crime scenes may contain insect artifacts as well as samples of human origin. While the presence of insects can be important evidence in forensic medicine and forensic entomology, the insect artifacts sometimes interfere with the interpretation of bloodstain pattern analysis (BPA) which can be critical for accurate crime reconstruction. Fly artifacts are especially complicated to distinguish from true bloodstains. Indeed, we encountered a murder scene with numerous bloodstains inconsistent with the cause of death and had trouble interpreting them. The morphological method has been developed to distinguish them, but this method has to rely on the analyst's experience and opinion. This study aims not only to distinguish fly artifacts from true bloodstains but also to identify fly species by detecting fly DNA in small amounts of bloodstains at the scenes. Melt curve analysis of real-time PCR (qPCR) targeting cytochrome c oxidase subunit 1 (CO1) of mitochondrial DNA (mtDNA) was able to detect fly DNA in bloodstains from a murder scene. The fly DNA was sequenced from the qPCR product, and the fly species were identified by BLAST search. Fluorescence-labeled specific primers for four species of necrophagous flies were designed based on the sequences of the CO1 region, and differences in the length of the amplification products were used to identify fly species from trace amounts of fly DNA in the artifacts.
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- 2022
6. 4′-Iodo-α-Pyrrolidinononanophenone Provokes Differentiated SH-SY5Y Cell Apoptosis Through Downregulating Nitric Oxide Production and Bcl-2 Expression
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Yuji, Sakai, Yoshifumi, Morikawa, Yukino, Nagao, Junta, Hattori, Koichi, Suenami, Emiko, Yanase, Tomohiro, Takayama, Akira, Ikari, and Toshiyuki, Matsunaga
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Pyrrolidines ,Brain-Derived Neurotrophic Factor ,General Neuroscience ,Apoptosis ,Tretinoin ,Ketones ,Nitric Oxide ,Toxicology ,Neuroblastoma ,Caspases ,Cell Line, Tumor ,Humans ,Cyclic AMP Response Element-Binding Protein ,bcl-2-Associated X Protein - Abstract
Abuse of pyrrolidinophenone derivatives (PPs) is known to cause severe damage to the central nervous system due to their high lipophilicity. In this study, we compared sensitivity to toxicity elicited by 4'-iodo-α-pyrrolidinononanophenone (I-α-PNP), one of the most potent cytotoxic derivatives among PPs synthesized previously, between SH-SY5Y cells differentiated by all-trans-retinoic acid (ATRA) and the undifferentiated cells, and found that the differentiated cells are more sensitive to I-α-PNP toxicity than the undifferentiated cells. Treatment with I-α-PNP elicited some apoptotic alterations (Bax expression, loss of mitrochondrial membrane potential, and activation of caspases) in the differentiated cells, whose patterns were similar to those in the undifferentiated cells. I-α-PNP treatment resulted in no significant alteration in Bcl-2 expression in the undifferentiated cells, whereas it considerably downregulated the protein expression in the differentiated cells, suggesting that the high I-α-PNP sensitivity of the differentiated cells is mainly due to downregulation of Bcl-2 expression. I-α-PNP treatment decreased nitric oxide (NO) production and neuronal NOS (nNOS) expression in the differentiated cells, and the patterns of I-α-PNP-evoked alterations in phosphorylation of cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) expression were almost the same as that in nNOS expression. Additionally, the addition of an NO donor restored the I-α-PNP-evoked alterations in expressions of Bcl-2, BDNF, and nNOS in the differentiated cells. These findings suggest that the downregulation of Bcl-2 expression by I-α-PNP in differentiated cells is attributed to the acceleration of two negative feedback loops (nNOS/NO/CREB loop and CREB/BDNF loop) triggered by decreased NO production.
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- 2022
7. The spontaneous symmetry breaking in Ta2NiSe5 is structural in nature
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Edoardo Baldini, Alfred Zong, Dongsung Choi, Changmin Lee, Marios H. Michael, Lukas Windgaetter, Igor I. Mazin, Simone Latini, Doron Azoury, Baiqing Lv, Anshul Kogar, Yifan Su, Yao Wang, Yangfan Lu, Tomohiro Takayama, Hidenori Takagi, Andrew J. Millis, Angel Rubio, Eugene Demler, and Nuh Gedik
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Multidisciplinary - Abstract
The excitonic insulator is an electronically driven phase of matter that emerges upon the spontaneous formation and Bose condensation of excitons. Detecting this exotic order in candidate materials is a subject of paramount importance, as the size of the excitonic gap in the band structure establishes the potential of this collective state for superfluid energy transport. However, the identification of this phase in real solids is hindered by the coexistence of a structural order parameter with the same symmetry as the excitonic order. Only a few materials are currently believed to host a dominant excitonic phase, Ta 2 NiSe 5 being the most promising. Here, we test this scenario by using an ultrashort laser pulse to quench the broken-symmetry phase of this transition metal chalcogenide. Tracking the dynamics of the material’s electronic and crystal structure after light excitation reveals spectroscopic fingerprints that are compatible only with a primary order parameter of phononic nature. We rationalize our findings through state-of-the-art calculations, confirming that the structural order accounts for most of the gap opening. Our results suggest that the spontaneous symmetry breaking in Ta 2 NiSe 5 is mostly of structural character, hampering the possibility to realize quasi-dissipationless energy transport.
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- 2023
8. Phononic soft mode behavior and a strong electronic background across the structural phase transition in the excitonic insulator Ta_{2}NiSe_{5}
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Min-Jae Kim, Armin Schulz, Tomohiro Takayama, Masahiko Isobe, Hidenori Takagi, and Stefan Kaiser
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Physics ,QC1-999 - Abstract
Ta_{2}NiSe_{5} became one of the most investigated candidate materials for hosting an excitonic insulator ground state. Many studies describe the corresponding phase transition as a condensation of excitons breaking a continuous symmetry. This view got challenged recently pointing out the importance of the loss of two mirror symmetries at a structural phase transition that occurs together with the semiconductor—excitonic insulator transition. For such a scenario an unstable optical zone-center phonon at low energy is proposed to drive the transition. Here we report on the experimental observation of such a soft mode behavior using Raman spectroscopy. In addition we find a novel spectral feature, likely of electronic or joint electronic and phononic origin, that is clearly distinct from the lattice dynamics and that becomes dominant at T_{c}. This suggests a picture of joint structural and electronic orders driving the phase transition.
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- 2020
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9. Superconductivity in (Ba,K)SbO3
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Minu Kim, Graham M. McNally, Hun-Ho Kim, Mohamed Oudah, Alexandra S. Gibbs, Pascal Manuel, Robert J. Green, Ronny Sutarto, Tomohiro Takayama, Alexander Yaresko, Ulrich Wedig, Masahiko Isobe, Reinhard K. Kremer, D. A. Bonn, Bernhard Keimer, Hidenori Takagi, University of St Andrews. School of Chemistry, and University of St Andrews. Centre for Designer Quantum Materials
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QC Physics ,Chemistry(all) ,Materials Science(all) ,Mechanics of Materials ,Mechanical Engineering ,NDAS ,General Materials Science ,General Chemistry ,Condensed Matter Physics ,QC - Abstract
Funding: This research was carried out in part due to funding from the Max Planck-UBC-UTokyo Centre for Quantum Materials. Part of the research described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council, the National Research Council, the Canadian Institutes of Health Research, the Government of Saskatchewan and the University of Saskatchewan. We thank the Science and Technology Facilities Council ISIS facility for the provision of beamtime. (Ba,K)BiO3 constitute an interesting class of superconductors, where the remarkably high superconducting transition temperature Tc of 30 K arises in proximity to charge density wave order. However, the precise mechanism behind these phases remains unclear. Here, enabled by high-pressure synthesis, we report superconductivity in (Ba,K)SbO3 with a positive oxygen–metal charge transfer energy in contrast to (Ba,K)BiO3. The parent compound BaSbO3−δ shows a larger charge density wave gap compared to BaBiO3. As the charge density wave order is suppressed via potassium substitution up to 65%, superconductivity emerges, rising up to Tc = 15 K. This value is lower than the maximum Tc of (Ba,K)BiO3, but higher by more than a factor of two at comparable potassium concentrations. The discovery of an enhanced charge density wave gap and superconductivity in (Ba,K)SbO3 indicates that strong oxygen–metal covalency may be more essential than the sign of the charge transfer energy in the main-group perovskite superconductors. Publisher PDF
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- 2022
10. Apoptotic mechanism in human brain microvascular endothelial cells triggered by 4′-iodo-α-pyrrolidinononanophenone: Contribution of decrease in antioxidant properties
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Yuji Sakai, Maki Taguchi, Yoshifumi Morikawa, Hidetoshi Miyazono, Koichi Suenami, Yuto Ochiai, Emiko Yanase, Tomohiro Takayama, Akira Ikari, and Toshiyuki Matsunaga
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Structure-Activity Relationship ,Pyrrolidines ,Molecular Structure ,Blood-Brain Barrier ,Cell Survival ,Brain ,Endothelial Cells ,Humans ,Apoptosis ,General Medicine ,Ketones ,Toxicology ,Antioxidants - Abstract
In this study, we newly synthesized four α-pyrrolidinononanophenone (α-PNP) derivatives [4'-halogenated derivatives and α-pyrrolidinodecanophenone (α-PDP)], and then performed the structure-cytotoxicity relationship analyses. The results showed the rank order for the cytotoxic effects, α-PNPα-PDP4'-fluoro-α-PNP4'-chrolo-α-PNP4'-bromo-α-PNP4'-iodo-α-PNP (I-α-PNP), and suggest that cytotoxicities of 4'-halogenated derivatives were more intensive than that of elongation of the hydrocarbon chain (α-PDP). We also surveyed the apoptotic mechanism of I-α-PNP in brain microvascular endothelial (HBME) cells that are utilized as the in vitro model of the blood-brain barrier. HBME cell treatment with I-α-PNP facilitated the apoptotic events (caspase-3 activation, externalization of phosphatidylserine, and DNA fragmentation), which were almost completely abolished by pretreating with antioxidants. In addition, the immunofluorescent staining revealed the enhanced production of hydroxyl radical in mitochondria by the I-α-PNP treatment, inferring that the I-α-PNP treatment triggers the apoptotic mechanism dependent on the enhanced ROS production in mitochondria. The treatment with I-α-PNP increased the production of cytotoxic aldehyde 4-hydroxy-2-nonenal and decreased the amount of reduced glutathione. Additionally, the treatment decreased the 26S proteasome-based proteolytic activities and aggresome formation. These results suggest that decrease in the antioxidant properties is also ascribable to HBME cell apoptosis elicited by I-α-PNP.
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- 2022
11. Safety of Concentrated Bioshell Calcium Oxide Water Application for Surface and Skin Disinfections against Pathogenic Microbes
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Masayuki Ishihara, Yuuki Hata, Sumiyo Hiruma, Tomohiro Takayama, Shingo Nakamura, Yoko Sato, Naoko Ando, Koichi Fukuda, Kaoru Murakami, and Hidetaka Yokoe
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bioshell calcium oxides ,calcium carbonate ,strong alkalinity ,disinfectant ,microbicidal activity ,safety ,Organic chemistry ,QD241-441 - Abstract
Immediately post-production, commercially available bioshell calcium oxide (BiSCaO) water is colorless, transparent, and strongly alkaline (pH 12.8), and is known to possess deodorizing properties and broad microbicidal activity. However, BiSCaO Water may represent a serious safety risk to the living body, given the strong alkalinity. This study aimed to investigate the safety of BiSCaO Water for use as an antiseptic/disinfectant despite concerns regarding its high alkalinity. The change over time in pH of BiSCaO Water was measured during air contact (stirring BiSCaO Water in ambient air). When sprayed on metal, plastic, wood piece, paper, and skin surfaces, the pH of BiSCaO Water decreased rapidly, providing a white powder coating upon drying. Scanning electron microscopy images, energy dispersive X-ray elemental mapping, and X-ray diffractograms showed that the dried powder residues of BiSCaO Water were composed primarily of calcium carbonate. These results suggested that BiSCaO Water is a potent reagent that may overcome the obstacles of being strongly alkaline, making this material appropriate for use in disinfection against pathogenic microbes.
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- 2020
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12. Bioshell Calcium Oxide-Containing Liquids as a Sanitizer for the Reduction of Histamine Production in Raw Japanese Pilchard, Japanese Horse Mackerel, and Chub Mackerel
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Sumiyo Hiruma, Masayuki Ishihara, Shingo Nakamura, Yoko Sato, Haruka Asahina, Koichi Fukuda, Tomohiro Takayama, Kaoru Murakami, and Hidetaka Yokoe
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histamine ,food poisoning ,bioshell calcium oxides ,bactericidal activity ,disinfectant ,Chemical technology ,TP1-1185 - Abstract
Recently, there has been an increase in the number of food poisoning cases associated with histamine in food, mainly in relation to histamine in fish. Here, we investigated methods to decrease histamine levels in Japanese pilchard, Japanese horse mackerel, and chub Mackerel, stored at 10 °C using various concentrations of heated scallop bioshell calcium oxide (BiSCaO) suspension, dispersion (BiSCaO + Na2HPO4), colloidal dispersion (BiSCaO + NapolyPO4), scallop shell powder (SSP) Ca(OH)2 in pure water (PW) or saline, and BiSCaO water. BiSCaO in a high alkaline pH solution chemically decomposes histamine poorly, but the partial flocculation/precipitation of histamine was observed with 1 and 0.2 wt.% BiSCaO dispersion and BiSCaO colloidal dispersion, respectively. Cleaning fish samples with BiSCaO suspension, dispersion, colloidal dispersion, or BiSCaO water remarkably reduced histamine levels and normal bacterial flora (coliform bacteria (CF) and total viable bacterial cells (TC)) after storage for four days at 10 °C, while much higher histamine levels were observed after cleaning with saline. These results suggest that cleaning fish with BiSCaO dispersion, colloidal dispersion, or BiSCaO water can significantly reduce histamine levels through their bactericidal activity against histamine-producing bacteria.
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- 2020
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13. Concentrated Bioshell Calcium Oxide (BiSCaO) Water Kills Pathogenic Microbes: Characterization and Activity
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Shingo Nakamura, Masayuki Ishihara, Yoko Sato, Tomohiro Takayama, Sumiyo Hiruma, Naoko Ando, Koichi Fukuda, Kaoru Murakami, and Hidetaka Yokoe
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calcium oxides ,deodorization ,disinfection ,heated scallop-shell powder ,microbicidal activity ,Organic chemistry ,QD241-441 - Abstract
Bioshell calcium oxide (BiSCaO) exhibits deodorizing properties and broad microbicidal activity. In this study, we examined possible utility of BiSCaO Water for that purpose. BiSCaO Water was prepared by adding 10 wt% BiSCaO to clean water and gently collecting the supernatant in a bottle. The same volume of clean water was gently poured onto the BiSCaO precipitate and the supernatant was gently collected in a bottle; this process was repeated fifty times. The produced BiSCaO Water contained nanoparticles (about 400–800 nm) composed of smaller nanoparticles (100–200 nm), and was colorless and transparent, with a pH > 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli such as NBRC 3972 and O-157:H7, Pseudomonas aeruginosa, Salmonella, and Staphylococcus aureus within 15 min. We compared BiSCaO Water with the other microbicidal reagents such as ethanol, BiSCaO, BiSCa(OH)2 suspensions, povidone iodine, NaClO, BiSCaO dispersion and colloidal dispersion with respect to deodorization activity and microbicidal efficacy. The results showed that BiSCaO Water was a potent reagent with excellent deodorization and disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).
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- 2020
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14. Bioshell Calcium Oxide (BiSCaO) Ointment for the Disinfection and Healing of Pseudomonas aeruginosa-Infected Wounds in Hairless Rats
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Tomohiro Takayama, Masayuki Ishihara, Shingo Nakamura, Yoko Sato, Sumiyo Hiruma, Koichi Fukuda, Kaoru Murakami, and Hidetaka Yokoe
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bioshell calcium oxide (BiSCaO) ,bactericidal activity ,ointment ,infected wound ,wound repair ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Bioshell calcium oxide (BiSCaO) possesses deodorizing properties and broad microbicidal activity. This study aimed to investigate the application of BiSCaO ointment for the prevention and treatment of infection in chronic wounds in healing-impaired patients, without delaying wound healing. The bactericidal activities of 0.04, 0.2, 1, and 5 wt% BiSCaO ointment, 3 wt% povidone iodine ointment, and control (ointment only) were compared to evaluate the in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Treatment of the infected wounds with 0.2 wt% BiSCaO ointment daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts compared with povidone iodine ointment and control (no wound cleaning). Although 5 wt% BiSCaO ointment provided the lowest bacterial counts during 3 days’ treatment, it delayed wound healing. Histological examinations showed significantly advanced granulation tissue and capillary formation in wounds treated with 0.2 wt% BiSCaO ointment for 3 days compared to wounds treated with the other ointments. This study suggested that using 0.2 wt% BiSCaO ointment as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects of BiSCaO on wound repair.
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- 2020
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15. Magnetic excitations and interactions in the Kitaev hyperhoneycomb iridate β−Li2IrO3
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Thomas Halloran, Yishu Wang, Mengqun Li, Ioannis Rousochatzakis, Prashant Chauhan, M. B. Stone, Tomohiro Takayama, Hidenori Takagi, N. P. Armitage, Natalia B. Perkins, and Collin Broholm
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- 2022
16. Preparation and Application of Bioshell Calcium Oxide (BiSCaO) Nanoparticle-Dispersions with Bactericidal Activity
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Yoko Sato, Masayuki Ishihara, Shingo Nakamura, Koichi Fukuda, Tomohiro Takayama, Sumiyo Hiruma, Kaoru Murakami, Masanori Fujita, and Hidetaka Yokoe
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scallop-shell powder ,calcium oxides ,dispersion ,microbicidal activity ,deodorization ,cyro-SEM ,Organic chemistry ,QD241-441 - Abstract
Scallop-shell powder (SSP) heated at high temperature exhibits high pH and broad antimicrobial activity. Bioshell calcium oxide (BiSCaO) is an SSP composed mainly of calcium oxide. It is poorly water-soluble under alkaline conditions and the generated precipitate can plug spray nozzles. The aim of this study was to establish that BiSCaO dispersion caused no significant CaO loss and plugging of spray nozzles, and to evaluate its deodorization and microbicidal abilities and its ability to reduce the concentrations of NO2− and NO3−. BiSCaO dispersions were prepared by mixing various concentrations of BiSCaO suspension, while phosphate compounds such as Na3PO4, Na2HPO4 or NaH2PO4 and the pH, average diameter, zeta potential, and form of the compounds with cryo-SEM were evaluated. We evaluated deodorization using tainted pork meat and microbicidal efficacy using contaminated suspension with normal bacterial flora. The concentration of NO2− and NO3− after mixing BiSCaO dispersion and pure water containing a high proportion of NO2− and NO3− were measured. BiSCaO dispersion formed with Na2HPO4, whose ratio to BiSCaO was 60%, showed a high pH (>12), a small particle diameter (>181 nm) and was stable for seven days. The BiSCaO dispersion showed higher deodorization and microbicidal activities than SSP-Ca(OH)2, which was mainly composed of Ca(OH)2. BiSCaO, but not SSP-Ca(OH)2, could reduce the concentration of NO2− and NO3− by more than 90% within 15 min. We developed a stable BiSCaO dispersion, and it had high deodorization and microbicidal efficacy. These activities of BiSCaO might result from the high pH caused by CaO hydration and a reduction activity causing active radical species.
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- 2019
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17. Synthesis and Application of Silver Nanoparticles (Ag NPs) for the Prevention of Infection in Healthcare Workers
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Shingo Nakamura, Masahiro Sato, Yoko Sato, Naoko Ando, Tomohiro Takayama, Masanori Fujita, and Masayuki Ishihara
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antiviral property ,healthcare workers (HCWs) ,medical application ,microbicidal property ,silver nanoparticles (Ag NPs) ,cytotoxicity ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Silver is easily available and is known to have microbicidal effect; moreover, it does not impose any adverse effects on the human body. The microbicidal effect is mainly due to silver ions, which have a wide antibacterial spectrum. Furthermore, the development of multidrug-resistant bacteria, as in the case of antibiotics, is less likely. Silver ions bind to halide ions, such as chloride, and precipitate; therefore, when used directly, their microbicidal activity is shortened. To overcome this issue, silver nanoparticles (Ag NPs) have been recently synthesized and frequently used as microbicidal agents that release silver ions from particle surface. Depending on the specific surface area of the nanoparticles, silver ions are released with high efficiency. In addition to their bactericidal activity, small Ag NPs (
- Published
- 2019
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18. The spontaneous symmetry breaking in Ta2NiSe5 is structural in nature.
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Baldini, Edoardo, Zong, Alfred, Dongsung Choi, Changmin Lee, Michael, Marios H., Windgaetter, Lukas, Mazin, Igor I., Latini, Simone, Azoury, Doron, Lv, Baiqing, Kogar, Anshul, Yifan Su, Yao Wang, Yangfan Lu, Tomohiro Takayama, Hidenori Takagi, Millis, Andrew J., Rubio, Angel, Demler, Eugene, and Gedik, Nuh
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BOSE-Einstein condensation ,SYMMETRY breaking ,ULTRASHORT laser pulses ,ULTRA-short pulsed lasers ,PHASES of matter ,PULSED power systems - Abstract
The excitonic insulator is an electronically driven phase of matter that emerges upon the spontaneous formation and Bose condensation of excitons. Detecting this exotic order in candidate materials is a subject of paramount importance, as the size of the excitonic gap in the band structure establishes the potential of this collective state for superfluid energy transport. However, the identification of this phase in real solids is hindered by the coexistence of a structural order parameter with the same symmetry as the excitonic order. Only a few materials are currently believed to host a dominant excitonic phase, Ta2NiSe5 being the most promising. Here, we test this scenario by using an ultrashort laser pulse to quench the broken-symmetry phase of this transition metal chalcogenide. Tracking the dynamics of the material's electronic and crystal structure after light excitation reveals spectroscopic fingerprints that are compatible only with a primary order parameter of phononic nature. We rationalize our findings through state-of-the-art calculations, confirming that the structural order accounts for most of the gap opening. Our results suggest that the spontaneous symmetry breaking in Ta2NiSe5 is mostly of structural character, hampering the possibility to realize quasi-dissipationless energy transport. [ABSTRACT FROM AUTHOR]
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- 2023
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19. A case of simultaneous double cancer of oral malignant melanoma and lung adenocarcinoma with nivolumab-induced destructive thyroiditis
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Tomohiro Takayama, Hidetaka Yokoe, Koji Yamamura, Ryota Yoshidome, Kaoru Murakami, and Chikashi Minemura
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Lung ,medicine.anatomical_structure ,business.industry ,Melanoma ,medicine ,Cancer research ,Adenocarcinoma ,General Medicine ,Nivolumab ,Double cancer ,medicine.disease ,business ,Thyroiditis - Published
- 2020
20. Magnetic and Electrical Properties of high-entropy rare-earth manganites
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Ashutosh Kumar, David Bérardan, Diana Dragoe, Eric Riviere, Tomohiro Takayama, Hidenori Takagi, and Nita Dragoe
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Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Materials Science ,Physics and Astronomy (miscellaneous) ,Strongly Correlated Electrons (cond-mat.str-el) ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,General Materials Science ,Energy (miscellaneous) - Abstract
Detailed investigations of structural, magnetic and electronic transport properties of hole-doped high-entropy rare-earth manganites are presented. The high-entropy samples (LaNdPrSmEu)$_{1-x}$Sr$_x$MnO$_3$ (0$\leq$\textit{x}$\leq$0.5), synthesized using the solid-state technique, show a change in the crystal structure from \textit{Pbnm} to \textit{R-3c} with increasing Sr substitution, attributed to the change in the tolerance factor. Prominent ferromagnetic ordering is observed in the sample with a rhombohedral structure (\textit{x}$\geq$0.3), originating from the dominant double exchange mechanism mediated by itinerant electrons. Further, the Curie temperature is smaller for the high-entropy sample with \textit{x}=0.3, as compared to La$_{0.7}$Sr$_{0.3}$MnO$_3$, suggesting a strong relation between the Curie temperature and the Mn-O-Mn bond angle associated with the reduced ionic radii at the rare-earth site. The electrical resistivity of the high-entropy samples is larger than those of La$_{1-x}$Sr$_x$MnO$_3$, which can be ascribed to the reduced bandwidth due to the enhanced structural distortion. A concomitant rise in magnetoresistance is observed for high-entropy samples with the increase in Sr concentration. These findings considering the configurational complexity of different rare-earths advance the understanding of high-entropy rare earth manganites., Comment: 11 pages, 6 figures, 1 table
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- 2022
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21. Blinding successfulness in antipsychotic trials of acute treatment for schizophrenia: a systematic review
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Aran Tajika, Toshi A Furukawa, Kiyomi Shinohara, Shino Kikuchi, Rie Toyomoto, Yuki Furukawa, Masami Ito, Kazufumi Yoshida, Yukiko Honda, Tomohiro Takayama, Johannes Schneider-Thoma, and Stefan Leucht
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- 2023
22. Limiting antibiotic prophylaxis in the treatment of maxillofacial fractures: A retrospective, single-center study of 81 patients
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Koji Yamamura, Kaoru Murakami, Tomohiro Takayama, Hidetaka Yokoe, Yasushi Kimura, and Chikashi Minemura
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medicine.medical_specialty ,RD1-811 ,medicine.medical_treatment ,Cefazolin ,Cefmetazole ,Single Center ,law.invention ,Maxillofacial fractures ,Randomized controlled trial ,law ,Medicine ,Internal fixation ,Antibiotic prophylaxis ,Internal medicine ,business.industry ,Medical record ,Retrospective cohort study ,Open reduction ,General Medicine ,RC31-1245 ,Surgery ,business ,medicine.drug - Abstract
Introduction The aim of this study was to investigate the validity of the duration for which we provide antibiotic prophylaxis to maxillofacial fracture patients who undergo open reduction and internal fixation (ORIF) in our hospital by retrospectively reviewing the incidence of surgical site infections (SSIs). Methods The medical records of 83 patients with maxillofacial fractures who underwent ORIF from April 2010 to October 2019 were retrospectively reviewed. The surgeon selected the proper surgical approach to the fracture site depending on the location and type of fractures. ORIF was performed by an intraoral, extraoral, or transconjunctival approach, or a combination of these approaches. No statistical investigation of differences in the method of prophylactic antibiotic administration and the occurrence of SSIs was conducted because of the small sample size. Results This retrospective study included 81 patients (58 males; median age 41 (range: 13–82) years; median BMI 22.4 (range: 16.5–33.6) kg/m2) with maxillofacial fractures. Two patients with infected fractures before operation withdrew from this study. The most common choice of antibiotic prophylaxis was cefmetazole for 2 days, followed by cefmetazole for 1 day. Two patients were diagnosed with an SSI; one was on cefazolin 2 g for 2 days, and the other was on cefmetazole 2–4 g for 2 days. In both cases the infection was successfully controlled, and implant removal was not required. Conclusions In principle, antibiotic prophylaxis for 2 days postoperatively is sufficient in ORIF for maxillofacial fracture, but a multicenter, prospective, randomized study may be required to confirm this.
- Published
- 2021
23. Recent Progress in the Development of Disinfectants from Scallop Shell-Derived Calcium Oxide for Clinical and Daily Use
- Author
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Naoko Ando, Shingo Nakamura, Tomohiro Takayama, Yuuki Hata, Sumiyo Hiruma, and Masayuki Ishihara
- Subjects
Disinfection methods ,2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,Chemistry ,medicine.drug_class ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Disinfectant ,Public Health, Environmental and Occupational Health ,Oxides ,Calcium Compounds ,Applied Microbiology and Biotechnology ,Disinfection ,Pectinidae ,Antiseptic ,Animal Shells ,Scallop ,medicine ,Animals ,Humans ,Food science ,Disinfectants - Abstract
The current pandemic of novel coronavirus disease (COVID-19) has highlighted the importance of disinfectants. As a raw material for next-generation disinfectants, scallop shell-derived calcium oxide (CaO) has been revealed to exhibit significant virucidal and microbicidal activities and is compatible with living tissues and the environment. This minireview summarizes recent progress in the development of disinfectants from scallop shell-CaO, focusing especially on studies of clinical and daily use applications. We describe the preparation, basic characteristics, and virucidal and microbicidal activities of scallop shell-CaO disinfectants. Furthermore, their applications in the disinfection of contaminated masks and the treatment of infected wounds are briefly introduced.
- Published
- 2021
24. A novel mutation at the AMEL primer binding region on the Y chromosome in AMELY negative male
- Author
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Tomohiro Takayama
- Subjects
Male ,Chromosomes, Human, Y ,Amelogenin ,Mutation ,Humans ,Female ,DNA Fingerprinting ,Alleles ,Pathology and Forensic Medicine - Abstract
Gender identification in forensic DNA typing is an important tool for criminal investigation as well as STR typing. Most methods are based on a size difference of amelogenin X and Y (AMELX and AMELY). There have been some reports that the method by amelogenin (AMEL) incorrectly typed some males as females because the AMELY allele is not detected. AMELY allele dropout is often caused by deletions encompassing AMELY on Yp11.2 and accompanied with Y-STR allele dropout (especially DYS458). However, an unusual deletion was found in our laboratory. The AMELY allele could be recovered by using another commercial kit and alternative AMEL primer sets, and the Y-STR markers resulted in a complete profile. Sequencing results showed that there was an 8 bp deletion in AMELY at the position corresponding to 41-48 bp downstream from the 3' end of the 6 bp deletion site in AMELX. This is considered a novel mutation at a primer binding region.
- Published
- 2021
25. Lowering of brain endothelial cell barrier function by exposure to 4′-iodo-α-pyrrolidinononanophenone
- Author
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Yuji, Sakai, Maki, Taguchi, Yoshifumi, Morikawa, Koichi, Suenami, Emiko, Yanase, Tomohiro, Takayama, Akira, Ikari, and Toshiyuki, Matsunaga
- Subjects
Pyrrolidines ,Matrix Metalloproteinase 9 ,Blood-Brain Barrier ,Brain ,Endothelial Cells ,Humans ,Matrix Metalloproteinase 2 ,Claudin-5 ,General Medicine ,Ketones ,Reactive Oxygen Species ,Toxicology - Abstract
Overuse of pyrrolidinophenones (PPs) is known to cause damage to vascular and central nervous systems, but little is known about its effect on brain endothelial barrier function. In this study, we found that exposure to 4'-iodo-α-pyrrolidinononanophenone (I-α-PNP), one of the most potently cytotoxic PPs, at sublethal concentrations decreases trans-endothelial electrical resistance and increases paracellular permeability across a monolayer of human brain microvascular endothelial cells. Treatment with I-α-PNP also elevated the production of superoxide anion. Furthermore, the treatment reduced the expression and plasma membrane localization of a tight junction protein claudin-5 (CLDN5), which was almost restored by pretreatment with an antioxidant N-acetyl-l-cysteine. These results indicate that I-α-PNP treatment may down-regulate the plasma membrane-localized CLDN5 by elevating the production of reactive oxygen species (ROS). The treatment with I-α-PNP increased the nuclear translocation of Forkhead box protein O1 (FoxO1), an oxidative stress-responsive transcription factor, and pretreating with a FoxO1 inhibitor ameliorated the decrease in CLDN5 mRNA. In addition, I-α-PNP treatment up-regulated the expression and secretion of matrix metalloproteinase-2 (MMP2) and MMP9, and the addition of an MMP inhibitor reversed the degradation of CLDN5 by I-α-PNP. Moreover, I-α-PNP treatment facilitated the activation of 26S proteasome-based proteolytic activity and pretreatment with an inhibitor of 26S proteasome, but not autophagy, suppressed the CLDN5 degradation by I-α-PNP. Accordingly, it is suggested that the down-regulation of CLDN5 by exposure to I-α-PNP is ascribable to suppression of the gene transcription due to FoxO1 nuclear translocation through ROS production and to acceleration both of the MMPs (MMP2 and MMP9)- and 26S proteasome-based proteolysis.
- Published
- 2022
26. Giant thermal Hall conductivity in the pseudogap phase of cuprate superconductors
- Author
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Gael Grissonnanche, Louis Taillefer, Etienne Lefrancois, Tomohiro Takayama, Sven Badoux, M. Lizaire, Nicolas Doiron-Leyraud, Jianshi Zhou, Sunseng Pyon, Anaëlle Legros, Francis Laliberte, Adrien Gourgout, Hidenori Takagi, Victor Zatko, and Shimpei Ono
- Subjects
Condensed Matter::Quantum Gases ,Physics ,Superconductivity ,Multidisciplinary ,Condensed matter physics ,Phonon ,Scattering ,Mott insulator ,Magnon ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Condensed Matter::Superconductivity ,0103 physical sciences ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,Cuprate ,010306 general physics ,0210 nano-technology ,Pseudogap - Abstract
The nature of the pseudogap phase of cuprates remains a major puzzle. Although there are indications that this phase breaks various symmetries, there is no consensus on its fundamental nature. Although Fermi-surface, transport and thermodynamic signatures of the pseudogap phase are reminiscent of a transition into a phase with antiferromagnetic order, there is no evidence for an associated long-range magnetic order. Here we report measurements of the thermal Hall conductivity $\kappa_{\rm xy}$ in the normal state of four different cuprates (Nd-LSCO, Eu-LSCO, LSCO, and Bi2201) and show that a large negative $\kappa_{\rm xy}$ signal is a property of the pseudogap phase, appearing with the onset of that phase at the critical doping $p^*$. Since it is not due to charge carriers -- as it persists when the material becomes an insulator, at low doping -- or magnons -- as it exists in the absence of magnetic order -- or phonons -- since skew scattering is very weak, we attribute this $\kappa_{\rm xy}$ signal to exotic neutral excitations, presumably with spin chirality. The thermal Hall conductivity in the pseudogap phase of cuprates is reminiscent of that found in insulators with spin-liquid states. In the Mott insulator LCO, it attains the highest known magnitude of any insulator.
- Published
- 2019
27. Superconductivity in (Ba,K)SbO
- Author
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Minu, Kim, Graham M, McNally, Hun-Ho, Kim, Mohamed, Oudah, Alexandra S, Gibbs, Pascal, Manuel, Robert J, Green, Ronny, Sutarto, Tomohiro, Takayama, Alexander, Yaresko, Ulrich, Wedig, Masahiko, Isobe, Reinhard K, Kremer, D A, Bonn, Bernhard, Keimer, and Hidenori, Takagi
- Abstract
(Ba,K)BiO
- Published
- 2021
28. Efficacy of Bioshell Calcium Oxide Water as Disinfectants to Enable Face Mask Reuse
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Masayuki Ishihara, Hidetaka Yokoe, Yuuki Hata, Yoko Sato, Sumiyo Hiruma, Naoko Ando, Shingo Nakamura, Koichi Fukuda, Kaoru Murakami, and Tomohiro Takayama
- Subjects
0106 biological sciences ,0303 health sciences ,Aqueous solution ,Hypochlorous acid ,030306 microbiology ,Disinfectant ,Public Health, Environmental and Occupational Health ,Masks ,Water ,Oxides ,Sterilization (microbiology) ,Calcium Compounds ,Pulp and paper industry ,01 natural sciences ,Applied Microbiology and Biotechnology ,Disinfection ,03 medical and health sciences ,chemistry.chemical_compound ,chemistry ,010608 biotechnology ,Sodium hypochlorite ,Hydrogen peroxide ,Calcium oxide ,Disinfectants - Abstract
Bioshell calcium oxide (BiSCaO) is derived from scallop shells and after heat treatment exhibits broad microbicidal activity. BiSCaO Water is a disinfectant prepared by collecting the aqueous layer after adding BiSCaO powder to water, is colorless and transparent, and has a pH of 12.8. We compared the utility of commercially available BiSCaO Water, ethanol, sodium hypochlorite, hypochlorous acid and hydrogen peroxide solutions as sterilization agents to enable the reuse of surgical and N95 face masks. The microbicidal efficacy of each disinfectant was evaluated using pieces of surgical and N95 face masks contaminated with normal bacterial flora. The results suggest that BiSCaO Water has excellent disinfection activity toward contaminated polypropylene masks and has minimal adverse effect on the structure of non-woven masks.
- Published
- 2021
29. Phononic soft mode behavior and a strong electronic background across the structural phase transition in the excitonic insulator Ta2NiSe5
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Hidenori Takagi, Tomohiro Takayama, Minjae Kim, Stefan Kaiser, Masahiko Isobe, and Armin Schulz
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Physics ,Phase transition ,symbols.namesake ,Condensed matter physics ,Phonon ,Continuous symmetry ,Exciton ,Condensation ,symbols ,Soft modes ,Raman spectroscopy ,Ground state - Abstract
Ta$_2$NiSe$_5$ became one of the most investigated candidate materials for hosting an excitonic insulator ground state. Many studies describe the corresponding phase transition as a condensation of excitons breaking a continuous symmetry. This view got challenged recently pointing out the importance of the loss of two mirror symmetries at a structural phase transition that occurs together with the semiconductor-excitonic insulator transition. For such a scenario an unstable optical zone-center phonon at low energy is proposed to drive the transition. Here we report on the experimental observation of such a soft mode behavior using Raman spectroscopy. In addition we find a novel spectral feature, likely of electronic or joint electronic and phononic origin, that is clearly distinct from the lattice dynamics and that becomes dominant at Tc. This suggests a picture of joint structural and electronic order driving the phase transition.
- Published
- 2020
30. Bioshell calcium oxide (BiSCaO) for cleansing and healing Pseudomonas aeruginosa-infected wounds in hairless rats
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Hidetaka Yokoe, Tomohiro Takayama, Masayuki Ishihara, Yoko Sato, Kaoru Murakami, Koichi Fukuda, and Shingo Nakamura
- Subjects
Male ,Hypochlorous acid ,Disinfectant ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,Rats, Hairless ,02 engineering and technology ,Microbial Sensitivity Tests ,medicine.disease_cause ,Microbiology ,Biomaterials ,chemistry.chemical_compound ,Mice ,In vivo ,Animal Shells ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Animals ,Pseudomonas Infections ,Therapeutic Irrigation ,Saline ,Povidone-Iodine ,Wound Healing ,integumentary system ,Pseudomonas aeruginosa ,business.industry ,Granulation tissue ,Oxides ,General Medicine ,Calcium Compounds ,Antimicrobial ,020601 biomedical engineering ,Bacterial Load ,Anti-Bacterial Agents ,Rats ,Disinfection ,Disease Models, Animal ,medicine.anatomical_structure ,chemistry ,020201 artificial intelligence & image processing ,Staphylococcal Skin Infections ,Wound healing ,business - Abstract
Background Scallop shell powder is called bioshell calcium oxide (BiSCaO), which is known to possess deodorizing properties and broad antimicrobial activity against various pathogenic microbes, including viruses, bacteria, spores, and fungi. Objective This study aims to investigate the applications of BiSCaO suspension cleansing in clinical situations, for instance for the prevention and treatment of infections in chronic wounds in healing-impaired patients, without delaying wound healing. Methods The bactericidal activities of 1000 ppm BiSCaO suspension; 500 ppm hypochlorous acid; 1000 ppm povidone iodine; and saline were compared to evaluate in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Results Cleansing of the infected wounds with BiSCaO suspension daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts, in comparison to hypochlorous acid, povidone iodine, and saline. Furthermore, histological examinations showed significantly advanced granulation tissue and capillary formation in the wounds cleansed with BiSCaO suspension than in those cleansed with the other solutions. Conclusions This study suggested that the possibility of using BiSCaO suspension as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects on wound repair.
- Published
- 2020
31. Bioshell Calcium Oxide (BiSCaO) Ointment for the Disinfection and Healing of Pseudomonas Aeruginosa-Infected Wounds in Hairless Rats
- Author
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Kaoru Murakami, Shingo Nakamura, Yoko Sato, Tomohiro Takayama, Sumiyo Hiruma, Koichi Fukuda, Masayuki Ishihara, and Hidetaka Yokoe
- Subjects
0301 basic medicine ,Disinfectant ,030106 microbiology ,bactericidal activity ,02 engineering and technology ,Pharmacology ,ointment ,medicine.disease_cause ,Bacterial counts ,Catalysis ,Wound cleaning ,Inorganic Chemistry ,lcsh:Chemistry ,03 medical and health sciences ,wound repair ,In vivo ,infected wound ,medicine ,Physical and Theoretical Chemistry ,skin and connective tissue diseases ,Molecular Biology ,lcsh:QH301-705.5 ,Spectroscopy ,integumentary system ,business.industry ,Pseudomonas aeruginosa ,Organic Chemistry ,Granulation tissue ,General Medicine ,021001 nanoscience & nanotechnology ,eye diseases ,Computer Science Applications ,Hairless ,body regions ,stomatognathic diseases ,medicine.anatomical_structure ,lcsh:Biology (General) ,lcsh:QD1-999 ,0210 nano-technology ,Wound healing ,business ,bioshell calcium oxide (BiSCaO) - Abstract
Bioshell calcium oxide (BiSCaO) possesses deodorizing properties and broad microbicidal activity. This study aimed to investigate the application of BiSCaO ointment for the prevention and treatment of infection in chronic wounds in healing-impaired patients, without delaying wound healing. The bactericidal activities of 0.04, 0.2, 1, and 5 wt% BiSCaO ointment, 3 wt% povidone iodine ointment, and control (ointment only) were compared to evaluate the in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Treatment of the infected wounds with 0.2 wt% BiSCaO ointment daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts compared with povidone iodine ointment and control (no wound cleaning). Although 5 wt% BiSCaO ointment provided the lowest bacterial counts during 3 days&rsquo, treatment, it delayed wound healing. Histological examinations showed significantly advanced granulation tissue and capillary formation in wounds treated with 0.2 wt% BiSCaO ointment for 3 days compared to wounds treated with the other ointments. This study suggested that using 0.2 wt% BiSCaO ointment as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects of BiSCaO on wound repair.
- Published
- 2020
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32. Concentrated Bioshell Calcium Oxide (BiSCaO) Water Kills Pathogenic Microbes: Characterization and Activity
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Kaoru Murakami, Koichi Fukuda, Shingo Nakamura, Tomohiro Takayama, Masayuki Ishihara, Sumiyo Hiruma, Yoko Sato, Naoko Ando, and Hidetaka Yokoe
- Subjects
business.product_category ,Pharmaceutical Science ,02 engineering and technology ,medicine.disease_cause ,Article ,Analytical Chemistry ,lcsh:QD241-441 ,03 medical and health sciences ,Colloid ,chemistry.chemical_compound ,lcsh:Organic chemistry ,Drug Discovery ,Bottle ,medicine ,Humans ,Physical and Theoretical Chemistry ,deodorization ,Calcium oxide ,Escherichia coli ,disinfection ,0303 health sciences ,Chromatography ,Ethanol ,Bacteria ,030306 microbiology ,Chemistry ,Organic Chemistry ,Water ,Pathogenic bacteria ,Oxides ,Calcium Compounds ,heated scallop-shell powder ,microbicidal activity ,021001 nanoscience & nanotechnology ,calcium oxides ,Chemistry (miscellaneous) ,Staphylococcus aureus ,Reagent ,Viruses ,Molecular Medicine ,0210 nano-technology ,business - Abstract
Bioshell calcium oxide (BiSCaO) exhibits deodorizing properties and broad microbicidal activity. In this study, we examined possible utility of BiSCaO Water for that purpose. BiSCaO Water was prepared by adding 10 wt% BiSCaO to clean water and gently collecting the supernatant in a bottle. The same volume of clean water was gently poured onto the BiSCaO precipitate and the supernatant was gently collected in a bottle, this process was repeated fifty times. The produced BiSCaO Water contained nanoparticles (about 400&ndash, 800 nm) composed of smaller nanoparticles (100&ndash, 200 nm), and was colorless and transparent, with a pH >, 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli such as NBRC 3972 and O-157:H7, Pseudomonas aeruginosa, Salmonella, and Staphylococcus aureus within 15 min. We compared BiSCaO Water with the other microbicidal reagents such as ethanol, BiSCaO, BiSCa(OH)2 suspensions, povidone iodine, NaClO, BiSCaO dispersion and colloidal dispersion with respect to deodorization activity and microbicidal efficacy. The results showed that BiSCaO Water was a potent reagent with excellent deodorization and disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).
- Published
- 2020
33. Skin Cleansing Technique with Disinfectant using Improved High-Velocity Steam-Air Micromist Jet Spray
- Author
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Hidetaka Yokoe, Shingo Nakamura, Kaoru Murakami, Koichi Fukuda, Masanori Fujita, Tomohiro Takayama, Masayuki Ishihara, and Yoko Sato
- Subjects
Chromatography ,Hypochlorous acid ,Bacteria ,Chemistry ,Swine ,Disinfectant ,Nozzle ,Public Health, Environmental and Occupational Health ,Sterilization ,Total Viable Count ,Applied Microbiology and Biotechnology ,Coliform bacteria ,chemistry.chemical_compound ,Steam ,Tap water ,Sodium hypochlorite ,Animals ,Calcium oxide ,Disinfectants ,Skin - Abstract
Application of a high-velocity steam-air micromist jet spray (HVS-AMJS) with disinfectants for cleansing the skin is proposed. Low-pressure steam is mixed with compressed air in a nozzle and then sprayed onto a surface of skin or material located approximately 22 cm from the nozzle. The temperature on the sprayed surface was controlled between 40oC and 45 oC. The improved HVS-AMJS installed scattering prevention cover with tap water effectively removed normal bacterial flora (total viable count and coliform bacteria) from contaminated skin pieces and pig skin wounds. Furthermore, the cleansing efficacy increased by advanced-treating with bio-shell calcium oxide (BiSCaO), hypochlorous acid (HClO), sodium hypochlorite (NaClO), povidone iodine, or chlorhexidine gluconate. Especially, the improved HVS-AMJS combined with BiSCaO had higher bactericidal activity than when combined with other disinfectants. This study suggests that application of the HVS-AMJS with disinfectants, especially BiSCaO, may be useful for skin cleansing to prevent infection.
- Published
- 2020
34. A case of acquired factor X deficiency diagnosed through the gingival bleeding
- Author
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Tomohiro Takayama, Tetsuo Ohnishi, Naoya Yoshihama, Shigeki Amekawa, Fumi Ogawa, and Yoshiaki Kitsukawa
- Subjects
medicine.medical_specialty ,business.industry ,Medicine ,business ,Dermatology ,Acquired Factor X Deficiency - Published
- 2018
35. Competition between spin-orbit coupling and molecular orbital crystal in pyrochlore ruthenate In2Ru2O7
- Author
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Aleksandra Krajewska, Tomohiro Takayama, Alexander Yaresko, Jürgen Nuss, Alexandra Gibbs, Sebastian Bette, and Hidenori Takagi
- Subjects
Inorganic Chemistry ,Structural Biology ,General Materials Science ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Biochemistry - Published
- 2021
36. Application of Colloidal Dispersions of Bioshell Calcium Oxide (BiSCaO) for Disinfection
- Author
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Koichi Fukuda, Kaoru Murakami, Tomohiro Takayama, Akinori Inoue, Yoko Sato, Shingo Nakamura, Sumiyo Hiruma, Hidetaka Yokoe, Heisuke Ohata, and Masayuki Ishihara
- Subjects
Flocculation ,Polymers and Plastics ,Nanoparticle ,02 engineering and technology ,colloidal dispersion ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Colloid ,Calcium oxide ,disinfection ,0303 health sciences ,Calcium hydroxide ,030306 microbiology ,Precipitation (chemistry) ,General Chemistry ,microbicidal activity ,021001 nanoscience & nanotechnology ,Phosphate ,calcium oxides ,flocculation/precipitation ,chemistry ,bioshell powder ,Polystyrene ,0210 nano-technology ,Nuclear chemistry - Abstract
Bioshell calcium oxide (BiSCaO) is a scallop-shell powder heated at a high temperature. BiSCaO is composed mainly of calcium oxide and exhibits broad microbicidal properties. The aim of this study is to evaluate the disinfection and decontamination abilities of BiSCaO colloidal dispersions with that of commercially available bioshell calcium hydroxide (BiSCa(OH)2) following the formation of flocculants/precipitates under strongly alkaline conditions (pH 11.5&ndash, 12.2). Various concentrations of BiSCaO and BiSCa(OH)2 colloidal dispersions were prepared by mixing with Na-polyPO4 (PP) and Na-triPO4 (TP) as flocculating agents. The microbicidal activities, and the degree of flocculation/precipitation of trypan blue, albumin, chondroitin sulfate, heparin, non-anticoagulant heparin carrying polystyrene (NAC-HCPS), and low-molecular-weight heparin/protamine nanoparticles (LMWH/P NPs) were dependent on the pH, the average particle diameter, and the concentration of BiSCaO or BiSCa(OH)2 and of the phosphate compound. BiSCaO (average particle diameter: 6 &mu, m) colloidal dispersions (0.2 wt.%) containing 0.15 wt.% PP or TP exhibited substantially stronger microbicidal activity and flocculation/precipitation under strongly alkaline conditions. These results suggest that BiSCaO colloidal dispersions together with phosphate compounds have practical applicability for disinfection.
- Published
- 2019
37. Superconductivity at 4.8 K and Violation of Pauli Limit in La
- Author
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Hajime, Ishikawa, Ulrich, Wedig, Jürgen, Nuss, Reinhard K, Kremer, Robert, Dinnebier, Marian, Blankenhorn, Mohammad, Pakdaman, Yosuke, Matsumoto, Tomohiro, Takayama, Kentaro, Kitagawa, and Hidenori, Takagi
- Abstract
We discovered superconductivity at 4.8 K in the hexagonal layered compound La
- Published
- 2019
38. Synthesis and Application of Silver Nanoparticles (Ag NPs) for the Prevention of Infection in Healthcare Workers
- Author
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Naoko Ando, Masahiro Sato, Shingo Nakamura, Yoko Sato, Masanori Fujita, Masayuki Ishihara, and Tomohiro Takayama
- Subjects
Silver ,Health Personnel ,Metal Nanoparticles ,Nanoparticle ,Halide ,Review ,02 engineering and technology ,Infections ,010402 general chemistry ,01 natural sciences ,Chloride ,Silver nanoparticle ,Catalysis ,lcsh:Chemistry ,Inorganic Chemistry ,Anti-Infective Agents ,Chlorides ,Drug Resistance, Multiple, Bacterial ,Specific surface area ,medicine ,Humans ,Physical and Theoretical Chemistry ,lcsh:QH301-705.5 ,Molecular Biology ,Spectroscopy ,Ions ,Chemistry ,Organic Chemistry ,General Medicine ,microbicidal property ,021001 nanoscience & nanotechnology ,Combinatorial chemistry ,Anti-Bacterial Agents ,0104 chemical sciences ,Computer Science Applications ,medical application ,lcsh:Biology (General) ,lcsh:QD1-999 ,cytotoxicity ,silver nanoparticles (Ag NPs) ,0210 nano-technology ,antiviral property ,healthcare workers (HCWs) ,medicine.drug - Abstract
Silver is easily available and is known to have microbicidal effect; moreover, it does not impose any adverse effects on the human body. The microbicidal effect is mainly due to silver ions, which have a wide antibacterial spectrum. Furthermore, the development of multidrug-resistant bacteria, as in the case of antibiotics, is less likely. Silver ions bind to halide ions, such as chloride, and precipitate; therefore, when used directly, their microbicidal activity is shortened. To overcome this issue, silver nanoparticles (Ag NPs) have been recently synthesized and frequently used as microbicidal agents that release silver ions from particle surface. Depending on the specific surface area of the nanoparticles, silver ions are released with high efficiency. In addition to their bactericidal activity, small Ag NPs (
- Published
- 2019
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39. Comparison of Various Disinfectants on Bactericidal Activity Under Organic Matter Contaminated Environments
- Author
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Hidetaka Yokoe, Masahiro Kuwabara, Tomohiro Takayama, Kaoru Murakami, Koichi Fukuda, Shingo Nakamura, Masanori Fujita, Sumiyo Hiruma, Masayuki Ishihara, and Yoko Sato
- Subjects
0106 biological sciences ,Hypochlorous acid ,Swine ,Disinfectant ,01 natural sciences ,Applied Microbiology and Biotechnology ,Suspension (chemistry) ,03 medical and health sciences ,chemistry.chemical_compound ,010608 biotechnology ,Animals ,Organic matter ,Food science ,Calcium oxide ,Skin ,chemistry.chemical_classification ,0303 health sciences ,Microbial Viability ,030306 microbiology ,Public Health, Environmental and Occupational Health ,Contamination ,Wood ,Coliform bacteria ,chemistry ,Sodium hypochlorite ,Disinfectants - Abstract
The bactericidal activity of heated bio-shell calcium oxide (BiSCaO) powder suspension (pH 12.4) , hypochlorous acid (HClO; pH 6), sodium hypochlorite (NaClO; pH 8) , povidone-iodine (Isodine solution®) , and chlorhexidine gluconate (Hibiscrub®) under organic matter contaminated environments were compared for tests conducted on wood scraps and pig skin pieces that were incubated with normal bacterial flora (total viable counts and coliform bacteria) . The test results showed that BiSCaO suspension had higher bactericidal activity than HClO and NaClO. Furthermore, more than 10-fold higher concentrations of antiseptics such as povidone-iodine and chlorhexidine gluconate were required to achieve bactericidal activity comparable to that of BiSCaO suspension. Our results demonstrate the possibility of using BiSCaO suspension under organic matter contaminated environments as a disinfectant for environmental and food hygiene applications.
- Published
- 2019
40. Crystal structure and stacking faults in the layered honeycomb, delafossite-type materials Ag
- Author
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Sebastian, Bette, Tomohiro, Takayama, Viola, Duppel, Agnieszka, Poulain, Hidenori, Takagi, and Robert E, Dinnebier
- Abstract
Powder samples of Ag3LiIr2O6 and Ag3LiRu2O6 were synthesized from α-Li2IrO3 and Li2RuO3 respectively by ion exchange in an AgNO3 melt. The crystal structures of the title compounds were solved from high resolution laboratory X-ray powder diffraction (XRPD) patterns and from pair distribution function (PDF) analysis using synchrotron X-ray powder diffraction data. In both crystal structures edge sharing LiO6/3- and (Ir/Ru)O6/3-octahedra form honeycomb like layers that are stacked in a staggered fashion. Silver cations, situated in-between the layers mediate the interlayer interactions by linear O-Ag-O bonds. Anisotropic peak broadening in the XRPD patterns and diffuse scattering occurring as streaks in the precession electron diffraction (PED) patterns indicate the presence of stacking faults, which could be also visualized by high resolution transmission electron microscopy (HRTEM). Possible alternative stacking sequences were derived from the ideal crystal and incorporated into a microstructure model. By applying a supercell approach that randomly generates and averages stacking sequences based on transition probabilities and combining it with a grid search algorithm, the microstructures, i.e. the degrees of faulting in the structures of the title compounds were refined to the measured XRPD data. In result the crystal structures of Ag3LiIr2O6 and Ag3LiRu2O6 were found to be vastly faulted with almost no coherence of the stacked layers.
- Published
- 2019
41. Bioshell Calcium Oxide-Containing Liquids as a Sanitizer for the Reduction of Histamine Production in Raw Japanese Pilchard, Japanese Horse Mackerel, and Chub Mackerel
- Author
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Hidetaka Yokoe, Yoko Sato, Kaoru Murakami, Tomohiro Takayama, Sumiyo Hiruma, Masayuki Ishihara, Haruka Asahina, Shingo Nakamura, and Koichi Fukuda
- Subjects
Flocculation ,Health (social science) ,bactericidal activity ,Plant Science ,lcsh:Chemical technology ,Health Professions (miscellaneous) ,Microbiology ,Article ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Chub mackerel ,lcsh:TP1-1185 ,Food science ,Histamine Production ,0303 health sciences ,biology ,030306 microbiology ,Chemistry ,biology.organism_classification ,histamine ,bioshell calcium oxides ,Horse mackerel ,Coliform bacteria ,Scallop ,food poisoning ,Dispersion (chemistry) ,disinfectant ,Histamine ,Food Science - Abstract
Recently, there has been an increase in the number of food poisoning cases associated with histamine in food, mainly in relation to histamine in fish. Here, we investigated methods to decrease histamine levels in Japanese pilchard, Japanese horse mackerel, and chub Mackerel, stored at 10 °, C using various concentrations of heated scallop bioshell calcium oxide (BiSCaO) suspension, dispersion (BiSCaO + Na2HPO4), colloidal dispersion (BiSCaO + NapolyPO4), scallop shell powder (SSP) Ca(OH)2 in pure water (PW) or saline, and BiSCaO water. BiSCaO in a high alkaline pH solution chemically decomposes histamine poorly, but the partial flocculation/precipitation of histamine was observed with 1 and 0.2 wt.% BiSCaO dispersion and BiSCaO colloidal dispersion, respectively. Cleaning fish samples with BiSCaO suspension, dispersion, colloidal dispersion, or BiSCaO water remarkably reduced histamine levels and normal bacterial flora (coliform bacteria (CF) and total viable bacterial cells (TC)) after storage for four days at 10 °, C, while much higher histamine levels were observed after cleaning with saline. These results suggest that cleaning fish with BiSCaO dispersion, colloidal dispersion, or BiSCaO water can significantly reduce histamine levels through their bactericidal activity against histamine-producing bacteria.
- Published
- 2020
42. Healing of Pseudomonas aeruginosa-infected wounds in diabetic db/db mice by weakly acidic hypochlorous acid cleansing and silver nanoparticle/chitin-nanofiber sheet covering
- Author
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Hidetaka Yokoe, Kaoru Murakami, Shingo Nakamura, Masayuki Ishihara, Tomoharu Kiyosawa, Yoko Sato, Tomohiro Takayama, Masahiro Kuwabara, and Koichi Fukuda
- Subjects
biology ,Hypochlorous acid ,Pseudomonas ,Granulation tissue ,030208 emergency & critical care medicine ,biology.organism_classification ,Antimicrobial ,Silver nanoparticle ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine.anatomical_structure ,Chitin ,chemistry ,Nanofiber ,medicine ,Surgery ,Wound healing ,Nuclear chemistry - Abstract
Weakly acidic hypochlorous acid (HClO; 200 ppm, pH 6.5) is effective against a broad range of microorganisms. We have previously reported a study of developing antimicrobial biomaterials made up of chitin-nanofiber sheet (CNFS) -immobilized silver nanoparticles (CNFS/Ag NPs) and showed that either cleansing with HClO or covering with CNFS/Ag NPs daily for more than 7 days resulted in delayed wound healing. This study aimed to evaluate disinfection and wound healing by a combination of cleansing with HClO and covering with CNFS/Ag NPs daily for 3 days. Applying HClO + CNFS/Ag NPs daily for 3 days and then cleansing with just pure water and covering with CNFS alone daily for 9 days were performed for Pseudomonas aeruginosa-infected wounds in db/db diabetic mice. We found a significant enhancement of wound healing and a reduction of bacteria counts compared to the controls. Histological examination showed significantly advanced granulation tissue and capillary formations in the wounds on Day 12. These results suggest that limited disinfection to 3 days with HClO + CNFS/Ag NPs may be sufficient to avoid negative effects on wound repair.
- Published
- 2020
43. Heparinoid Complex-Based Heparin-Binding Cytokines and Cell Delivery Carriers
- Author
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Masayuki Ishihara, Masanori Fujita, Hidetaka Yokoe, Koichi Fukuda, Shingo Nakamura, Yoko Sato, Kaoru Murakami, and Tomohiro Takayama
- Subjects
heparinoid-carrying polystyrene ,Pharmaceutical Science ,Biocompatible Materials ,Heparinoid ,Review ,Analytical Chemistry ,Extracellular matrix ,Glycosaminoglycan ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Sulfation ,Coated Materials, Biocompatible ,Polysaccharides ,Drug Discovery ,glycosaminoglycan ,medicine ,Animals ,Humans ,Physical and Theoretical Chemistry ,Heparinoids ,heparinoid-based biomaterials ,polyelectrolyte complexes ,heparinoid ,030304 developmental biology ,Drug Carriers ,0303 health sciences ,Molecular Structure ,Heparin ,Sulfates ,Organic Chemistry ,Antithrombin ,Anticoagulants ,Heparan sulfate ,Extracellular Matrix ,heparin-binding cytokines ,Biochemistry ,chemistry ,Chemistry (miscellaneous) ,030220 oncology & carcinogenesis ,Cytokines ,Molecular Medicine ,Heparitin Sulfate ,Protein Binding ,medicine.drug - Abstract
Heparinoid is the generic term that is used for heparin, heparan sulfate (HS), and heparin-like molecules of animal or plant origin and synthetic derivatives of sulfated polysaccharides. Various biological activities of heparin/HS are attributed to their specific interaction and regulation with various heparin-binding cytokines, antithrombin (AT), and extracellular matrix (ECM) biomolecules. Specific domains with distinct saccharide sequences in heparin/HS mediate these interactions are mediated and require different highly sulfated saccharide sequences with different combinations of sulfated groups. Multivalent and cluster effects of the specific sulfated sequences in heparinoids are also important factors that control their interactions and biological activities. This review provides an overview of heparinoid-based biomaterials that offer novel means of engineering of various heparin-binding cytokine-delivery systems for biomedical applications and it focuses on our original studies on non-anticoagulant heparin-carrying polystyrene (NAC-HCPS) and polyelectrolyte complex-nano/microparticles (N/MPs), in addition to heparin-coating devices.
- Published
- 2019
44. Photo-excited dynamics in the excitonic insulator Ta
- Author
-
Daniel, Werdehausen, Tomohiro, Takayama, Gelon, Albrecht, Yangfan, Lu, Hidenori, Takagi, and Stefan, Kaiser
- Abstract
The excitonic insulator is an intriguing correlated electron phase formed of condensed excitons. A promising candidate is the small band gap semiconductor Ta
- Published
- 2018
45. Photo-excited Dynamics in the Excitonic Insulator Ta2NiSe5
- Author
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Tomohiro Takayama, Yangfan Lu, Stefan Kaiser, Daniel Werdehausen, Gelon Albrecht, and Hidenori Takagi
- Subjects
Physics ,Condensed Matter::Quantum Gases ,Strongly Correlated Electrons (cond-mat.str-el) ,Condensed matter physics ,business.industry ,Band gap ,Phonon ,Exciton ,FOS: Physical sciences ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,01 natural sciences ,Photoexcitation ,Condensed Matter - Strongly Correlated Electrons ,Semiconductor ,Excited state ,0103 physical sciences ,Quasiparticle ,General Materials Science ,Charge carrier ,010306 general physics ,0210 nano-technology ,business - Abstract
The excitonic insulator is an intriguing correlated electron phase formed of condensed excitons. A promising candidate is the small band gap semiconductor Ta2NiSe5. Here we investigate the quasiparticle and coherent phonon dynamics in Ta2NiSe5 in a time resolved pump probe experiment. Using the models originally developed by Kabanov et al. for superconductors, we show that the material's intrinsic gap can be described as almost temperature independent for temperatures up to about 250 K to 275 K. This behavior supports the existence of the excitonic insulator state in Ta2NiSe5. The onset of an additional temperature dependent component to the gap above these temperatures suggests that the material is located in the BEC-BCS crossover regime. Furthermore, we show that this state is very stable against strong photoexcitation, which reveals that the free charge carriers are unable to effectively screen the attractive Coulomb interaction between electrons and holes, likely due to the quasi one-dimensional structure of Ta2NiSe5., 27 pages, 8 figures
- Published
- 2018
46. Involvement of soil bacteria in ABO blood mistyping
- Author
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Rie Takai, Tomohiro Takayama, Naoki Takada, Chikahiro Mori, Kohei Nakamura, Kazuhiro Takamizawa, and Yoshihisa Watanabe
- Subjects
food.ingredient ,Glycoside Hydrolases ,Bacillus ,Enzyme-Linked Immunosorbent Assay ,Biology ,ABO Blood-Group System ,Pathology and Forensic Medicine ,Microbiology ,food ,Antigen ,ABO blood group system ,Humans ,Agar ,Soil Microbiology ,Soil bacteria ,chemistry.chemical_classification ,Glycoside ,Galactosidase activity ,biology.organism_classification ,Molecular biology ,Issues, ethics and legal aspects ,Blood Grouping and Crossmatching ,chemistry ,Blood Group Antigens ,Bacteria - Abstract
The current study investigated whether ABO blood mistyping of human biological samples is induced by soil bacteria. A total of 380 bacterial strains were isolated from 50 discrete soil samples using human blood agar, and glycosidase activity evaluated for all strains using 4-nitropheny glycosides (4-nitrophenyl n-acetyl-α-D-galactosaminide, 4-nitrophenyl-α-D-galactopyranoside, 4-nitrophenyl-α-L-fucopyranoside) as substrates. Thirteen strains possessed α-galactosidase activity, and 16S rRNA sequence analysis revealed a close relatedness to the genus Bacillus. An indirect competitive enzyme-linked immunosorbent assay confirmed seven strains exhibited type B antigen degradation activity. These results demonstrated that 1.8% of the bacteria isolated from soil, were Bacillus sp., possessed galactosidase activity, and had the potential to cause ABO blood mistyping.
- Published
- 2015
47. Solution of the heavily stacking faulted crystal structure of the honeycomb iridate H
- Author
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Sebastian, Bette, Tomohiro, Takayama, Kentaro, Kitagawa, Riku, Takano, Hidenori, Takagi, and Robert E, Dinnebier
- Abstract
A powder sample of pure H
- Published
- 2017
48. Exposure characteristics of positive tone electron beam resist containing p-chloro-α-methylstyrene
- Author
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Manae Sonoda, Tomohiro Takayama, Ryoichi Hoshino, Hironori Asada, Minako Iwakuma, Yukiko Kishimura, and Shunsuke Ochiai
- Subjects
chemistry.chemical_compound ,Materials science ,chemistry ,Resist ,Polymer chemistry ,Analytical chemistry ,Copolymer ,Phenyl group ,Dry etching ,Solubility ,Electron beam resist ,Electron-beam lithography ,Amyl acetate - Abstract
The positive tone resist consisted of methyl-α-chloroacrylate (ACM) and α-methylstyrene (MS) has higher sensitivity and higher dry etching resistance than poly (methylmethacrylate) (PMMA) due to the presence of a chlorine atom and a phenyl group. Copolymers consisted of ACM and p-chloro-α-methylstyrene (PCMS), where the additional chlorine atom is introduced in phenyl group compared with ACM-MS resist are synthesized and their exposure characteristics are investigated. ACM-PCMS resist with the ACM:PCMS composition ratio of 49:51 indicates the high solubility for amyl acetate developer. As the ACM composition ratio increases, the solubility of ACM-PCMS resist is suppressed. In both ACM-PCMS and ACM-MS resists, the sensitivity decreases while the contrast increases with increasing ACM ratio. When the composition ratio of ACM:PCMS is 69:31, 100/100 nm line and space pattern having a good shape is obtained at 120 μC/cm2 which is comparable to the required exposure dose for conventional ACM-MS resist with ACM:MS=50:50. Dry etching resistance of ACM:PCMS resists for Ar gas is also presented.
- Published
- 2017
49. Development of an indirect competitive ELISA for the detection of ABO blood group antigens
- Author
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Yoshihisa Watanabe, Mizuho Iida, Kohei Nakamura, Chikahiro Mori, Naoki Takada, Kazuhiro Takamizawa, Tomohiro Takayama, and Rie Takai
- Subjects
Analyte ,Saliva ,biology ,medicine.drug_class ,Chemistry ,Blood Stains ,Antibodies, Monoclonal ,Enzyme-Linked Immunosorbent Assay ,Proteinase K ,Monoclonal antibody ,Stain ,Molecular biology ,ABO Blood-Group System ,Pathology and Forensic Medicine ,Issues, ethics and legal aspects ,Blood Grouping and Crossmatching ,Antigen ,Antibody Specificity ,ABO blood group system ,biology.protein ,medicine ,Humans ,Forensic Pathology - Abstract
We developed an indirect competitive enzyme-linked immunosorbent assay (ELISA) for the detection of ABO blood group antigens in human samples; in particular for blood stains. ABO blood group antigens conjugated to polyacrylamide were used for immobilized antigen. ABO blood group antigens were extracted from blood stains using a novel method involving pre-incubation with proteinase K (PK), followed by heat treatment. The extracts (analytes) were combined with either anti-A or -B monoclonal antibodies (mAbs), and added directly to the antigen-coated wells. The anti-A and -B mAbs were captured by either ABO blood group antigens present in the analyte or by the immobilized blood group antigens. Peroxidase-conjugated anti-mouse IgM antibody was used to detect anti-A and -B mAbs complexed with immobilized blood group antigens, and a colorimetric reaction using o-phenylenediamine/H2O2 used for its measurement. The ELISA developed in this study was able to detect blood group antigens in blood, saliva and blood stains. The detection limit for unknown blood, saliva and blood stain were determined as 1:200, 1:32 and 1:16. Overall the ABO blood grouping ELISA can be used with relative ease for the high throughput screening of biological samples for the detection of ABO blood group antigens.
- Published
- 2014
50. A case of intramuscular lipoma of the mental region
- Author
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Hiroshi Nozawa, Junko Nakajima, Syuri Hada, Tomohiro Takayama, Yasunori Sato, and Shinya Watanabe
- Subjects
medicine.medical_specialty ,business.industry ,medicine ,Intramuscular Lipoma ,business ,Surgery - Published
- 2014
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