Publications by authors named "Shinichiro Kato"

Objective: Radiation therapy is an indispensable treatment for head and neck cancer; however, the development of radiation-induced oral mucositis causes erythema and ulcers in the patient's oral cavity, resulting in severe pain. The purpose of this study was to investigate the efficacy of Episil® in the treatment of radiation-induced oral mucositis.

Study Design: Seventy-six F344 rats were randomly divided into an Episil® group (n=38) and a control group (n=38).

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In this study, we synthesized novel donor-π-acceptor (D-π-A) functional dyes bearing a carbonyl-bridged bithiophene as a π-conjugated spacer and evaluated the absorption and fluorescence properties as well as the photostability. The developed dyes - possess an ,-diphenylaminophenyl electron donor unit and an electron acceptor unit such as a formyl group (), an (,-diethylthiobarbituryl)methylene moiety (), or a (3-dicyanomethylidene-1-indanon-2-yl)methylene moiety (). The absorption spectra of - in dichloromethane at room temperature showed absorption maxima at 569 nm, 631 nm, and 667 nm, respectively, and the stronger acceptors in and led to enhancement of the ICT character.

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A dibenzoazaborine dication (Dpa2DBAB2+) was synthesized and characterized as a resonance hybrid of the open-shell singlet (OS) and quinoidal closed-shell states (CS) based on electron spin resonance spectroscopy and density functional theory calculations. Furthermore, the azaborine ring of the dication exhibited remarkable antiaromaticity.

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One- and two-electron-oxidized species of two π-conjugated systems that adopt close π-stacking structures are referred to as π-mers and π-dimers, respectively. These cationic species exhibit intriguing physicochemical properties that are markedly distinct from those of their parent monomeric radical cations. In this study, we have achieved the chemical oxidation of a newly designed tethered dimer comprising two planar sulfur- and carbon-bridged triphenylamine (SCBT) units linked by a 1,8-naphthalene moiety to obtain the corresponding π-mer and π-dimer as crystalline materials.

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Most giant viruses including Mimiviridae family build large viral factories within the host cytoplasms. These giant viruses are presumed to possess specific genes that enable the rapid and massive replication of their large double-stranded DNA genomes within viral factories. It has been revealed that a functionally uncharacterized protein, MutS7, is expressed during the operational phase of the viral factory.

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Article Synopsis
  • Burkholderia sp. HME13 can use ergothioneine, a strong antioxidant, as a nitrogen source and involves multiple enzymes like ErtA, ErtB, ErtC, and ErtD for its utilization.
  • The study identified the ertE gene, which encodes an enzyme (ErtE) that works best at 60°C and pH 7.0 and is essential for processing N-carbamyl-l-glutamic acid.
  • ErtE's activity is dependent on metal ions, and its role in ergothioneine utilization in Burkholderia sp. HME13 indicates a specific mechanism for how this strain processes nutrients.
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Three thienopyrrole-fused thiadiazole (TPT) fluorescent dyes featuring a common amide linker and different alkoxy substituents on peripheral trialkoxybenzene moieties were synthesized, and their self-assembly behavior in solution was investigated. The obtained results revealed a substantial steric effect of the alkoxy substituents on the supramolecular polymerization mechanism, which results from a combination of π-stacking and hydrogen (H)-bonding interactions. Detailed spectroscopic measurements revealed that with increasing steric demand of the substituents, the supramolecular polymerization processes in pure methylcyclohexane (MCH) or a mixture of MCH and toluene become temperature-sensitive and enthalpically favorable, resulting in a change from the isodesmic assembly mechanism to the cooperative mechanism.

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  • ChatGPT is an AI tool that’s starting to be used for reviewing scientific articles, but there are concerns about its accuracy and biases.
  • The study looked at how well ChatGPT’s reviews matched those of human reviewers on 20 medical research articles, where it was found that ChatGPT agreed with human comments only sometimes.
  • The results showed that ChatGPT performed best with general comments but struggled more with specific details, indicating it doesn’t fully replace human reviewers yet.
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Article Synopsis
  • ATP-dependent chromatin remodeling complexes, specifically non-canonical BAF (ncBAF), play important roles in hematopoietic stem cells (HSCs), but their functions haven't been fully explored.* -
  • The study focuses on BRD9, a key component of ncBAF, finding that its loss increases chromatin accessibility, leading to a preference for myeloid cell development while hindering B cell formation.* -
  • BRD9 is shown to interact with CTCF, which affects gene expression and chromatin structure in HSCs, highlighting ncBAF's crucial role in determining cell fate in both normal and cancerous blood cell development.*
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Background: Pancreaticoduodenectomy has been associated with a high mortality rate and significant postoperative morbidity. Recently, perioperative oral care management has been reported to be effective in preventing postoperative pneumonia and surgical site infection. In this study, we examined the effect of perioperative oral care management in reducing complications after pancreaticoduodenectomy, including surgical site infection.

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A new diradical based on diindenocarbazole or difluorenopyrrole was synthesized and experimentally characterized by optical, electrochemical, and magnetic techniques, as well as quantum chemical calculations. The isomerism of these structures tunes the diradical character and the associated properties, representing a unique case of such important modulation. A full study of the electronic structure was carried out considering the perturbative interactions between different canonical forms as well as the anti-aromatic character of the molecular cores.

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Recombinant 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid desulfhydrase (ErtC) derived from Burkholderia sp. HME13 was purified to homogeneity. Here, ErtC's kinetic parameters, optimum reaction temperature and pH, and stability at varying temperatures and pH and the effects of various additives on ErtC activity were determined.

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A series of boron difluoride (BF) complexes of azinylcarbazoles 1b-1h were synthesized, and the effects of the structure of azine moieties on the photophysical and electrochemical properties of the BF complexes were clarified. UV-vis analysis of 1b with quinoline, 1c with isoquinoline, and fully fused 1d revealed that fusion with a benzene ring to a pyridylcarbazole BF complex (1a) resulted in red shifts of longest-maximum absorption wavelengths (). UV-vis analysis of 1e and 1f with pyrimidine, 1g with pyridazine, and 1h with pyrazine revealed that substitution of a carbon atom to a nitrogen atom in 1a also resulted in red shifts of .

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Purpose: Stridor during emergence from anesthesia is not rare in children managed with supraglottic airway (SGA). However, we know little about the mechanisms of stridor and behavior of the vocal cords (VC). This study aimed to clarify patterns of VC movement and laryngeal airway maintenance function during recovery from anesthesia in children with SGA.

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We have demonstrated site-selective radical reactions of the kinetically stable open-shell singlet diradicaloids difluoreno[3,4-:4',3'-]thiophene (DFTh) and difluoreno[3,4-:4',3'-]furan (DFFu) with tributyltin hydride (HSn(-Bu)) and azo-based radical initiators. Treatment of these diradicaloids with HSn(-Bu) induces hydrogenation at the -carbon in the five-membered rings, while treatment with 2,2'-azobis(isobutyronitrile) (AIBN) induces substitution at the carbon atoms in the peripheral six-membered rings. We have also developed one-pot substitution/hydrogenation reactions of DFTh/DFFu with various azo-based radical initiators and HSn(-Bu).

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In our previous study, ertABC genes encoding ergothionase, thiourocanate hydratase, and 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid desulfhydrase were identified, all of which may be involved in ergothioneine utilization of Burkholderia sp. HME13. In this study, we identify the ertD gene encoding metal-dependent hydantoin-5-propionic acid amidohydrolase in this strain.

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A structurally constrained, double-helical S,C-bridged tetraphenyl--phenylenediamine (TPPD) has been synthesized. The stable radical cation of the S,C-bridged TPPD was generated by chemical oxidation, and the electron spin was found to be delocalized over the entire π-conjugated framework. The excellent conformational stability of the neutral molecule facilitated the separation of its enantiomers.

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Parapharyngeal space tumors have poor subjective symptoms and often grow until diagnosed; therefore, mandibular transection may be needed to obtain a wider field of view during surgery. However, if a median lower lip incision is performed for the mandibular transection, esthetic problems occur after surgery. Here, we report two cases of parapharyngeal space tumors that were removed with a mandibular lateral segment-osteotomy technique without median lower lip incision to avoid esthetic problems.

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Dysregulation of the tumor-intrinsic epigenetic circuit is a key driver event for the development of cancer. Accumulating evidence suggests that epigenetic and/or genetic drivers stimulate intrinsic oncogenic pathways as well as extrinsic factors that modulate the immune system. These modulations indeed shape the tumor microenvironment (TME), allowing pro-oncogenic factors to become oncogenic, thereby contributing to cancer development and progression.

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Oral leukoplakia, which presents as white lesions in the oral cavity, including on the tongue, is precancerous in nature. Conservative treatment is preferable, since surgical removal can markedly reduce the patient's quality of life. In the present study, we focused on the flavonoid apigenin as a potential compound for preventing carcinogenesis, and an apigenin-loaded mucoadhesive oral film was prepared using a three-dimensional (3D) bioprinter (semi-solid extrusion-type 3D printer).

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Bacteriophages (phages) are the most diverse and abundant life-form on Earth. Jumbophages are phages with double-stranded DNA genomes longer than 200 kbp. Among these, some jumbophages with uracil in place of thymine as a nucleic acid base, which we have tentatively termed "dU jumbophages" in this study, have been reported.

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Four difluorenoheteroles having a central quinoidal core with the heteroring varying as furan, thiophene, its dioxide derivative and pyrrole have shown to be medium character diradicals. Solid-state structures, optical, photophysical, magnetic, and electrochemical properties have been discussed in terms of diradical character, variation of aromatic character and captodative effects (electron affinity). Organic field-effect transistors (OFETs) have been prepared, showing balanced hole and electron mobilities of the order of 10  cm  V  s or ambipolar charge transport which is first inferred from their redox amphoterism.

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Carnosine is a naturally occurring dipeptide and a functional component in foods, while also showing health-promoting effects. Generally, food-derived carnosine is quantified via high-performance liquid chromatography (HPLC). We have developed a method for quantifying carnosine in foods using microbial enzymes, β-Ala-Xaa dipeptidase (BapA) and histidine ammonia-lyase (HAL).

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During the self-assembly of π-conjugated molecules, linkers and substituents can potentially add supportive noncovalent intermolecular interactions to π-stacking interactions. Here, we report the self-assembly behavior of thienopyrrole-fused thiadiazole (TPT) fluorescent dyes that possess ester or ether linkers and dodecyloxy side chains in solution and the condensed phase. A comparison of the self-association behavior of the ester- and ether-bridged compounds in solution using detailed UV-vis, fluorescence, and NMR spectroscopic studies revealed that the subtle replacement of the ether linkers by ester linkers leads to a distinct increase in the association constant (ca.

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Loss-of-function mutations of JAK1/2 impair cancer cell responsiveness to IFNγ and immunogenicity. Therefore, an understanding of compensatory pathways to activate IFNγ signaling in cancer cells is clinically important for the success of immunotherapy. Here we demonstrate that the transcription factor SOX10 hinders immunogenicity of melanoma cells through the IRF4-IRF1 axis.

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