12,803 results on '"MASATOSHI"'
Search Results
2. Supramolecular liquid crystals from the dimer of L‐shaped molecules with tertiary amide end groups
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Yuki Sawatari, Yoshimichi Shimomura, Masato Takeuchi, Riki Iwai, Takuya Tanaka, Eiji Tsurumaki, Masatoshi Tokita, Junji Watanabe, and Gen‐ichi Konishi
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mesogen ,self‐assembly ,semectic phase ,supramolecular liquid crystal ,tertiary amide ,variable‐temperature Fourier‐transform infrared ,Chemistry ,QD1-999 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Supramolecular liquid crystals (SLCs) are attractive materials for fabricating devices with new optoelectronic functions. Conventional SLCs are made from hydrogen‐bonded mesogens. However, these mesogens suffer from high melting points, and the types of formable aggregates are limited owing to the directionality of the hydrogen bonding. Therefore, to fabricate non‐hydrogen‐bonded SLCs, we hypothesized that the introduction of tertiary amide groups into calamitic molecules would be advantageous because they have an L‐shaped structure with N‐ or C‐alkyl side chains not aligned along the long axis and the flexibility to undergo cis–trans isomerization. In this study, we developed a novel non‐hydrogen‐bonded SLC by assembling an L‐shaped dimer composed of calamitic molecules (phenyltolanes) with tertiary amides at their ends. These molecules exhibited a smectic B phase. The phase transition temperature of the SLCs from crystal to liquid crystal phase was low despite the long π‐conjugated core. Wide‐angle X‐ray diffraction and variable‐temperature Fourier‐transform infrared measurements revealed dimer formation by weak intermolecular interactions, that is, the molecular recognition of L‐shaped molecules, and mobility of the alkyl groups attached to amide driven by cis–trans isomerization in the liquid crystal phase. Thus, cis–trans isomerization of tertiary amides contributed enormously to the formation and lower clearing points of this SLC. The developed method can be used not only to develop non‐hydrogen‐bonded SLCs but also to develop novel soft matter with controlled properties by incorporating the SLCs, as the aggregates can be controlled to impart desired functionalities.
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- 2024
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3. Small-angle x-ray scattering analysis of carbon fiber voids considering void length distribution
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Daisuke Kimura, Masahiko Demura, Kenji Nagata, Toshihira Irisawa, Yoshiki Sugimoto, Wataru Takarada, and Masatoshi Shioya
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Carbon fibers ,Small-angle x-ray scattering ,Microvoids ,Chemistry ,QD1-999 - Abstract
The analysis method proposed by Ruland et al. is widely used to analyze the void lengths in carbon fibers, but it could not apply to mesophase pitch-based carbon fibers. We thought that the reason for the inability to analyze pitch-based carbon fibers was the length distribution of voids that Ruland neglected. We investigated an analytical method that considers the length distribution of voids in carbon fibers. The proposed new method could be applied to various carbon fibers from polyacrylonitrile and mesophase pitch. The analysis results revealed that the average length of voids in mesophase pitch-based carbon fibers is not only long but also widely distributed. On the other hand, the voids of carbon fibers tend to be longer as the crystallite length is longer in both polyacrylonitrile-based and mesophase-based carbon fibers. It suggests that the growth of void length is strongly influenced by the growth of crystallites in the plane direction.
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- 2024
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4. Toward Automated Structural Design for Controlled Vibration Characteristics Using Topology Optimization and Computer Vision in Space Missions
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Musaddiq Al Ali, Masatoshi Shimoda, and Marc Naguib
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additive manufacturing ,computer-aided design ,computer vision ,topology optimization ,eigen frequency ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study explores the integration of computer vision with topology optimization for additive manufacturing, with a focus on maximizing eigenfrequency in a design domain. Utilizing custom-developed photogrammetry software, high-resolution images are processed to generate detailed 3D models, which are subsequently converted to STL files with precision. Adaptive meshing in COMSOL 5.3 Multiphysics, controlled through a MATLAB 2023 API, ensures optimal mesh resolution. Prioritizing resource conservation in extraterrestrial environments, the original volume is reduced by 50% while preserving structural integrity. The design domain undergoes rigorous topology optimization in MATLAB, supported by COMSOL’s advanced FEM simulation. The optimized design exhibits a 57% performance improvement and a 50% weight reduction, maintaining the desired vibration characteristics, validating the efficacy of the modifications. Moreover, the case with an eccentric mass shows a significant 64% increase in eigenfrequency.
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- 2024
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5. Phase Transition Field Effect Transistor Observed in an α-(BEDT-TTF)2I3 Single Crystal
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Ryosuke Ando, Ryo Watanuki, Kazuhiro Kudo, Hyuma Masu, and Masatoshi Sakai
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charge order ,field-effect transistor ,BEDT-TTF ,electron correlation ,organic ,phase transition transistor ,Chemistry ,QD1-999 - Abstract
The metal–insulator transition induced by the gate electric field in the charge order phase of the α-(BEDT-TTF)2I3 single-crystal field-effect transistor (FET) structure was clearly observed near the phase transition temperature. An abrupt increase in the electrical conductance induced by the applied gate electric field was evident, which corresponds to the partial dissolution of the charge order phase triggered by the gate electric field. The estimated nominal dissolved charge order region (i.e., the gate-induced metallic region) was overestimated in 130–150 K, suggesting additional effects such as Joule heating. On the other hand, in the lower temperature region below 120 K, the corresponding dissolved charge order was several monolayers of BEDT-TTF, suggesting that it is possible to dissolve the charge order phase within the bistable temperature region.
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- 2023
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6. Evaluation of Radiation Doses Received by Physicians during Permanent 198Au Grain Implant Brachytherapy for Oral Cancer
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Yohei Inaba, Keiichi Jingu, Masaki Fujisawa, Kazuki Otomo, Hiroki Ishii, Toshiki Kato, Yuuki Murabayashi, Masatoshi Suzuki, Masayuki Zuguchi, and Koichi Chida
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radiation protection and safety ,198Au grain (Au-198 permanent grain) ,brachytherapy ,radiation therapy ,oral cancer ,eye lens dose ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Brachytherapy is a practical, effective procedure for the local treatment of cancer; it delivers a high radiation dose to a limited tissue volume while sparing the surrounding normal tissues. Although the clinical benefit of brachytherapy is clear, there have been very few studies on the radiation dose received by physicians during the procedure. Furthermore, no study has investigated the eye radiation dose received by physicians performing 198Au grain (seed) brachytherapy, using an eye dosimeter. Recently, the International Commission on Radiological Protection (ICRP) recommended significantly reducing the occupational lens dose limit, from 150 to 20 mSv/yr (100 mSv/5 years). Therefore, it has become essential to evaluate the eye radiation doses of medical workers. We evaluated the eye radiation dose of a brachytherapy physician performing 198Au permanent grain implantation for tongue cancer; this is the first study on this topic. The maximum eye dose was ~0.1 mSv/procedure, suggesting that it is unlikely to exceed the ICRP limit (20 mSv/yr) for the lens, unless many procedures are performed with inappropriate radiation protection. To reduce the dose of radiation received by 198Au grain brachytherapy physicians, it is necessary to use additional lead shielding equipment when preparing the treatment needles, i.e., when loading the grains. This study provides useful information on radiation exposure of physicians conducting 198Au permanent grain brachytherapy.
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- 2024
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7. Cytoprotective Role of Autophagy in CDIP1 Expression-Induced Apoptosis in MCF-7 Breast Cancer Cells
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Ryuta Inukai, Kanako Mori, Masatoshi Maki, Terunao Takahara, and Hideki Shibata
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apoptosis ,autophagy ,CDIP1 ,proapoptotic protein ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Cell death-inducing p53-target protein 1 (CDIP1) is a proapoptotic protein that is normally expressed at low levels and is upregulated by genotoxic and endoplasmic reticulum stresses. CDIP1 has been reported to be localized to endosomes and to interact with several proteins, including B-cell receptor-associated protein 31 (BAP31) and apoptosis-linked gene 2 (ALG-2). However, the cellular and molecular mechanisms underlying CDIP1 expression-induced apoptosis remain unclear. In this study, we first demonstrated that CDIP1 was upregulated after treatment with the anticancer drug adriamycin in human breast cancer MCF-7 cells but was degraded rapidly in the lysosomal pathway. We also demonstrated that treatment with the cyclin-dependent kinase 5 (CDK5) inhibitor roscovitine led to an increase in the electrophoretic mobility of CDIP1. In addition, a phosphomimetic mutation at Ser-32 in CDIP1 resulted in an increase in CDIP1 expression-induced apoptosis. We also found that CDIP1 expression led to the induction of autophagy prior to apoptosis. Treatment of cells expressing CDIP1 with SAR405, an inhibitor of the class III phosphatidylinositol 3-kinase VPS34, caused a reduction in autophagy and promoted apoptosis. Therefore, autophagy is thought to be a defense mechanism against CDIP1 expression-induced apoptosis.
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- 2024
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8. Indoor AR Navigation Framework Based on Geofencing and Image-Tracking with Accumulated Error Correction
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Min Lu, Masatoshi Arikawa, Kohei Oba, Keiichi Ishikawa, Yuhan Jin, Tomihiro Utsumi, and Ryo Sato
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indoor navigation ,augmented reality ,spatial tracking ,geofencing ,accumulated positioning error calibration ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study presents a novel framework for improving indoor augmented reality (AR) navigation with modern smartphone technology, which is achieved by addressing two major challenges: managing large absolute coordinate spaces and reducing error accumulation in camera-based spatial tracking. Our contribution is significant in two ways. First, we integrate geofencing with indoor navigation by considering spatial tracking errors, timing for audio guidance, and dynamic 3D arrow visualization for effective local-to-global spatial coordinate transformation. This method achieves precise local positioning and seamlessly integrates with larger spatial contexts, overcoming the limitations of current AR systems. Second, we introduce a periodic image-based calibration approach to minimize the inherent error accumulation in camera-based tracking, enhancing accuracy over longer distances. Unlike prior studies focusing on individual technologies, our work explores the software architecture of indoor AR navigation by providing a comprehensive framework for its design and practical use. The practicality of our approach is validated through the implementation of a smartphone application at the Mineral Industry Museum of Akita University, highlighting the limitations of component technologies and demonstrating our framework’s effectiveness.
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- 2024
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9. Microwave-assisted C–C bond formation of diarylacetylenes and aromatic hydrocarbons on carbon beads under continuous-flow conditions
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Tsuyoshi Yamada, Wataru Teranishi, Naoya Sakurada, Seiya Ootori, Yuka Abe, Tomohiro Matsuo, Yasuharu Morii, Masatoshi Yoshimura, Takeo Yoshimura, Takashi Ikawa, and Hironao Sajiki
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Chemistry ,QD1-999 - Abstract
Abstract The synthesis of polycyclic aromatic compounds generally requires stoichiometric oxidants or homogeneous metal catalysts, however, the risk of contamination of inorganic residues can affect their properties. Here we present a microwave (MW)-assisted platinum on beaded activated carbon (Pt/CB)-catalyzed C–C bond formation of diarylacetylenes and aromatic hydrocarbons under continuous-flow conditions. Various fused aromatic compounds were continuously synthesized via dehydrogenative C(sp2)–C(sp2) and C(sp2)–C(sp3) bond formation with yields of up to 87% without the use of oxidants and bases. An activated, local reaction site on Pt/CB in the flow reaction channel reaching temperatures of more than three hundred degrees Celsius was generated in the catalyst cartridge by selective microwave absorption in CB with an absorption efficiency of > 90%. Mechanistic experiments of the transformation reaction indicated that a constant hydrogen gas supply was essential for activating Pt. This is an ideal reaction with minimal input energy and no waste production.
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- 2023
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10. Investigation of the Nanoparticulation Method and Cell-Killing Effect following the Mitochondrial Delivery of Hydrophobic Porphyrin-Based Photosensitizers
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Rina Naganawa, Hanjun Zhao, Yuta Takano, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi Harashima, and Yuma Yamada
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mitochondria ,photodynamic therapy ,mitochondrial delivery ,MITO-Porter ,photosensitizer ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Photodynamic therapy is expected to be a less invasive treatment, and strategies for targeting mitochondria, the main sources of singlet oxygen, are attracting attention to increase the efficacy of photodynamic therapy and reduce its side effects. To date, we have succeeded in encapsulating the photosensitizer rTPA into MITO-Porter (MP), a mitochondria-targeted Drug Delivery System (DDS), aimed at mitochondrial delivery of the photosensitizer while maintaining its activity. In this study, we report the results of our studies to alleviate rTPA aggregation in an effort to improve drug efficacy and assess the usefulness of modifying the rTPA side chain to improve the mitochondrial retention of MITO-Porter, which exhibits high therapeutic efficacy. Conventional rTPA with anionic side chains and two rTPA analogs with side chains that were converted to neutral or cationic side chains were encapsulated into MITO-Porter. Low-MP (MITO-Porter with Low Drug/Lipid) exhibited high drug efficacy for all three types of rTPA, and in Low-MP, charged rTPA-encapsulated MP exhibited high drug efficacy. The cellular uptake and mitochondrial translocation capacities were similar for all particles, suggesting that differences in aggregation rates during the incorporation of rTPA into MITO-Porter resulted in differences in drug efficacy.
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- 2024
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11. High-Resolution Printing of Various Electronic Materials by Electrophotography
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Chen Yi Ngu, Kaito Kozuki, Hinata Oshida, Sang Bin Lee, Raiki Hanazaki, Sayaka Kado, Kazuhiro Kudo, and Masatoshi Sakai
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printed electronics ,flexible electronics ,additive manufacturing ,conductive nanoparticle ,electrophotography ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Electrophotography is a digital, on-demand, dry, and page printing technique that operates based on toner particles of electronic materials using an electrostatic force and generates an electrical circuit via distribution of the toner particles. We developed a 10 μm linewidth resolution with various electronic materials, including conductors, semiconductors, and insulators, without any chemical pretreatments on the substrate films, while a 5 μm resolution was also possible for limited materials. The electrical resistivity of the printed Ag–Ni after an intense pulse light sintering was comparable to that of commercial indium tin oxide transparent films.
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- 2024
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12. A Comprehensive Assessment of Tear-Film-Oriented Diagnosis (TFOD) in a Dacryoadenectomy Dry Eye Model
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Saki Sakakura, Emi Inagaki, Yuichiro Ochiai, Masatoshi Yamamoto, Naofumi Takai, Taeko Nagata, Kazunari Higa, Yasunori Sato, Hiroshi Toshida, Dogru Murat, Masatoshi Hirayama, Yoko Ogawa, Kazuno Negishi, and Shigeto Shimmura
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dry eye ,tear film breakup ,animal model ,dry eye therapy ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Tear film instability is a major cause of dry eye disease. In order to treat patients with short tear film breakup time (TBUT)-type dry eye, the development of tear film stabilizing agents is essential. However, the lack of an appropriate animal model of tear film instability has made drug development difficult. Although rabbit dry eye models have been reported in the past, there are only a few reports that focus on tear film instability. Herein, we assessed the tear film stability of a rabbit dry eye model induced by dacryoadenectomy. A clinical evaluation of the ocular surface, interferometry, and histological assessments of the cornea and conjunctiva were performed. Following the removal of the lacrimal glands, TBUT was shortened significantly, with dimple and random breakup patterns prominently observed. Furthermore, the blink rate in this model increased after dacryoadenectomy, suggesting that this model partially captured the phenotypes of human short TBUT-type dry eye and may be useful as an animal model for investigating potential drug candidates.
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- 2023
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13. Inhibitory Effects of Shikonin Dispersion, an Extract of Lithospermum erythrorhizon Encapsulated in β-1,3-1,6 Glucan, on Streptococcus mutans and Non-Mutans Streptococci
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Ryota Nomura, Yuto Suehiro, Fumikazu Tojo, Saaya Matayoshi, Rena Okawa, Masakazu Hamada, Shuhei Naka, Michiyo Matsumoto-Nakano, Rika Unesaki, Kazuya Koumoto, Keiko Kawauchi, Takahito Nishikata, Tatsuya Akitomo, Chieko Mitsuhata, Masatoshi Yagi, Toshiro Mizoguchi, Koki Fujikawa, Taizo Taniguchi, and Kazuhiko Nakano
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shikonin ,dispersion ,Streptococcus mutans ,non-mutans streptococci ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Shikonin is extracted from the roots of Lithospermum erythrorhizon, and shikonin extracts have been shown to have inhibitory effects on several bacteria. However, shikonin extracts are difficult to formulate because of their poor water solubility. In the present study, we prepared a shikonin dispersion, which was solubilized by the inclusion of β-1,3-1,6 glucan, and analysed the inhibitory effects of this dispersion on Streptococcus mutans and non-mutans streptococci. The shikonin dispersion showed pronounced anti-S. mutans activity, and inhibited growth of and biofilm formation by this bacterium. The shikonin dispersion also showed antimicrobial and antiproliferative effects against non-mutans streptococci. In addition, a clinical trial was conducted in which 20 subjects were asked to brush their teeth for 1 week using either shikonin dispersion-containing or non-containing toothpaste, respectively. The shikonin-containing toothpaste decreased the number of S. mutans in the oral cavity, while no such effect was observed after the use of the shikonin-free toothpaste. These results suggest that shikonin dispersion has an inhibitory effect on S. mutans and non-mutans streptococci, and toothpaste containing shikonin dispersion may be effective in preventing dental caries.
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- 2024
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14. Elucidating Differences in Early-Stage Centrosome Amplification in Primary and Immortalized Mouse Cells
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Masakazu Tanaka, Masaki Yamada, Masatoshi Mushiake, Masataka Tsuda, and Masanao Miwa
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centrosome amplification ,chromosome instability ,cell differentiation ,PARP inhibition ,DNA damage (doxorubicin, irradiation) ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The centrosome is involved in cytoplasmic microtubule organization during interphase and in mitotic spindle assembly during cell division. Centrosome amplification (abnormal proliferation of centrosome number) has been observed in several types of cancer and in precancerous conditions. Therefore, it is important to elucidate the mechanism of centrosome amplification in order to understand the early stage of carcinogenesis. Primary cells could be used to better understand the early stage of carcinogenesis rather than immortalized cells, which tend to have various genetic and epigenetic changes. Previously, we demonstrated that a poly(ADP-ribose) polymerase (PARP) inhibitor, 3-aminobenzamide (3AB), which is known to be nontoxic and nonmutagenic, could induce centrosome amplification and chromosomal aneuploidy in CHO-K1 cells. In this study, we compared primary mouse embryonic fibroblasts (MEF) and immortalized MEF using 3AB. Although centrosome amplification was induced with 3AB treatment in immortalized MEF, a more potent PARP inhibitor, AG14361, was required for primary MEF. However, after centrosome amplification, neither 3AB in immortalized MEF nor AG14361 in primary MEF caused chromosomal aneuploidy, suggesting that further genetic and/or epigenetic change(s) are required to exhibit aneuploidy. The DNA-damaging agents doxorubicin and γ-irradiation can cause cancer and centrosome amplification in experimental animals. Although doxorubicin and γ-irradiation induced centrosome amplification and led to decreased p27Kip protein levels in immortalized MEF and primary MEF, the phosphorylation ratio of nucleophosmin (Thr199) increased in immortalized MEF, whereas it decreased in primary MEF. These results suggest that there exists a yet unidentified pathway, different from the nucleophosmin phosphorylation pathway, which can cause centrosome amplification in primary MEF.
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- 2023
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15. Increased Mortality Risk at Septic Condition in Inflammatory Skin Disorders and the Effect of High-Fat Diet Consumption
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Mai Nishimura, Takehisa Nakanishi, Masako Ichishi, Yoshiaki Matsushima, Masatoshi Watanabe, and Keiichi Yamanaka
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inflammatory skin disease ,atopic dermatitis ,psoriasis ,sepsis ,lipopolysaccharide ,high-fat diet ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
In recent years, attention has increasingly focused on various infectious diseases. Although some fatalities are directly attributed to the causative virus, many result from complications and reactive inflammation. Patients with comorbidities are at a higher risk of mortality. Refractory skin conditions such as atopic dermatitis, psoriasis, and epidermolysis bullosa, known for an elevated risk of sepsis, partly owe this to compromised surface barrier function. However, the detailed mechanisms underlying this phenomenon remain elusive. Conversely, although the detrimental effects of a high-fat diet on health, including the onset of metabolic syndrome, are widely recognized, the association between diet and susceptibility to sepsis has not been extensively explored. In this study, we examined the potential causes and pathogenesis of increased sepsis susceptibility in inflammatory skin diseases using a mouse dermatitis model: keratin 14-driven caspase-1 is overexpressed (KCASP1Tg) in mice on a high-fat diet. Our findings reveal that heightened mortality in the dermatitis mouse model is caused by the inflamed immune system due to the chronic inflammatory state of the local skin, and administration of LPS causes a rapid increase in inflammatory cytokine levels in the spleen. Intake of a high-fat diet exacerbates these cytokine levels. Interestingly, we also observed a reduced expression of Toll-like receptor 4 (TLR4) in monocytes from KCASP1Tg mice, potentially predisposing these animals to heightened infection risks and associated complications. Histological analysis showed a clear decrease in T and B cells in the spleen of KCASP1Tg mice fed a high-fat diet. Thickening of the alveolar wall, inflammatory cell infiltration, and alveolar hemorrhage were more prominent in the lungs of KCASP1Tg and KCASP1Tg with fat mice. We postulate that the chronic, non-infectious inflammation induces a negative feedback loop within the inflammatory cascade, and the suppressed expression of TLR4 renders the mice more susceptible to infections. Therefore, it is imperative for individuals with chronic skin inflammation to closely monitor disease progression upon infection and seek timely and appropriate treatment. Additionally, chronic inflammation of adipose tissue, induced by high-fat food intake, combined with dermatitis inflammation, may exacerbate infections, necessitating a review of dietary habits.
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- 2023
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16. Expression of Tumor Suppressor FHIT Is Regulated by the LINC00173-SNAIL Axis in Human Lung Adenocarcinoma
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Takahito Suzuki, Satoshi Sakai, Kosuke Ota, Mika Yoshida, Chiharu Uchida, Hiroyuki Niida, Takafumi Suda, Masatoshi Kitagawa, and Tatsuya Ohhata
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lncRNA ,LINC00173 ,SNAIL ,FHIT ,lung adenocarcinoma ,tumor suppressor gene ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Long non-coding RNAs (lncRNAs) play a critical role in a variety of human diseases such as cancer. Here, to elucidate a novel function of a lncRNA called LINC00173, we investigated its binding partner, target gene, and its regulatory mechanism in lung adenocarcinoma, including the A549 cell line and patients. In the A549 cell line, RNA immunoprecipitation (RIP) assays revealed that LINC00173 efficiently binds to SNAIL. RNA-seq and RT-qPCR analyses revealed that the expression of FHIT was decreased upon LINC00173 depletion, indicating that FHIT is a target gene of LINC00173. Overexpression of SNAIL suppressed and depletion of SNAIL increased the expression of FHIT, indicating that SNAIL negatively regulates FHIT. The downregulation of FHIT expression upon LINC00173 depletion was restored by additional SNAIL depletion, revealing a LINC00173-SNAIL-FHIT axis for FHIT regulation. Data from 501 patients with lung adenocarcinoma also support the existence of a LINC00173-SNAIL-FHIT axis, as FHIT expression correlated positively with LINC00173 (p = 1.75 × 10−6) and negatively with SNAIL (p = 7.00 × 10−5). Taken together, we propose that LINC00173 positively regulates FHIT gene expression by binding to SNAIL and inhibiting its function in human lung adenocarcinoma. Thus, this study sheds light on the LINC00173-SNAIL-FHIT axis, which may be a key mechanism for carcinogenesis and progression in human lung adenocarcinoma.
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- 2023
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17. Using a Paper-Based Analytical Device Designed For Remote Learning Environments to Achieve Simple Quantitative Colorimetry without Micropipettes
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Komatsu, Takeshi, Gabatino, Ryan Russel, Hofilen~a, Harrienica, Maeki, Masatoshi, Ishida, Akihiko, Tani, Hirofumi, and Tokeshi, Manabu
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The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.
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- 2021
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18. Effective Method for Multi-Probe Electrical Measurements of Organic Single Crystals: Four-Terminal Natural Adhesion Contact
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Hiroki Watanabe, Sakyo Ushikubo, Masatoshi Sakai, Kazuhiro Kudo, and Hyuma Masu
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organic crystals ,4-probe measurement ,field effect transistor ,charge order ,correlated system ,natural adhesion ,Chemistry ,QD1-999 - Abstract
A technique to establish electrical contact and perform multi-probe electrical measurements (e.g., four-probe measurements), even at low temperatures, is presented in this work. The natural adhesion contact (NAC) is applicable to the wide range of dimensions of organic crystals. Furthermore, the precise electrode patterns required to carry out multi-probe measurements are guaranteed, in contrast to fine conductive paste painting methods. We demonstrate four-probe electrical measurements of α-(BEDT-TTF)2I3 (where BEDT-TTF = bis(ethylenedithio) tetrathiafulvalene) at temperatures down to 100 K. The obtained temperature dependence showed a steep meta l–insulator transition and exhibited zero hysteresis throughout several measurement sequences.
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- 2022
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19. Local Differential Privacy Image Generation Using Flow-Based Deep Generative Models
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Hisaichi Shibata, Shouhei Hanaoka, Yang Cao, Masatoshi Yoshikawa, Tomomi Takenaga, Yukihiro Nomura, Naoto Hayashi, and Osamu Abe
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differential privacy ,deep generative models ,medical images ,privacy protection ,database ,image obfuscation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Diagnostic radiologists need artificial intelligence (AI) for medical imaging, but access to medical images required for training in AI has become increasingly restrictive. To release and use medical images, we need an algorithm that can simultaneously protect privacy and preserve pathologies in medical images. To address this, we introduce DP-GLOW, a hybrid that combines the local differential privacy (LDP) algorithm with GLOW, one of the flow-based deep generative models. By applying a GLOW model, we disentangle the pixelwise correlation of images, which makes it difficult to protect privacy with straightforward LDP algorithms for images. Specifically, we map images to the latent vector of the GLOW model, where each element follows an independent normal distribution. We then apply the Laplace mechanism to this latent vector to achieve ϵ-LDP, which is one of the LDP algorithms. Moreover, we applied DP-GLOW to chest X-ray images to generate LDP images while preserving pathologies. The ϵ-LDP-processed chest X-ray images obtained with DP-GLOW indicate that we have obtained a powerful tool for releasing and using medical images for training AI.
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- 2023
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20. Efficacy of Lenvatinib Combined with Transcatheter Intra-Arterial Therapies for Patients with Advanced-Stage of Hepatocellular Carcinoma: A Propensity Score Matching
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Shigeo Shimose, Hideki Iwamoto, Takashi Niizeki, Masatoshi Tanaka, Tomotake Shirono, Etsuko Moriyama, Yu Noda, Masahito Nakano, Hideya Suga, Ryoko Kuromatsu, Takuji Torimura, Hironori Koga, and Takumi Kawaguchi
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lenvatinib ,TACE ,HAIC ,advance-stage ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
This study aimed to evaluate the effect of lenvatinib (LEN) combined with transcatheter intra-arterial therapy (TIT) for advanced-stage hepatocellular carcinoma (HCC) after propensity score matching (PSM). This retrospective study enrolled 115 patients with advanced-stage HCC who received LEN treatment. The patients were categorized into the LEN combined with TIT group (n = 30) or the LEN monotherapy group (n = 85). After PSM, 38 patients (LEN + TIT group, n = 19; LEN monotherapy group, n = 19) were analyzed. The median overall survival (OS) in the LEN + TIT group was significantly higher than that in the LEN monotherapy group (median survival time (MST): 28.1 months vs. 11.6 months, p = 0.014). The OS in the LEN combined with transcatheter arterial chemoembolization and LEN combined with hepatic arterial infusion chemotherapy groups was significantly higher than that in the LEN monotherapy group (MST 20.0 vs. 11.6 months, 30.2 vs. 11.6 months, p = 0.048, and p = 0.029, respectively). Independent factors associated with OS were alpha-fetoprotein and LEN combined with TIT. The indications for LEN combined with TIT were age
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- 2023
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21. Effect of Liver Fibrosis on Oral and Gut Microbiota in the Japanese General Population Determined by Evaluating the FibroScan–Aspartate Aminotransferase Score
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Satoshi Sato, Chikara Iino, Daisuke Chinda, Takafumi Sasada, Tetsuyuki Tateda, Masatoshi Kaizuka, Hiroki Nomiya, Go Igarashi, Kaori Sawada, Tatsuya Mikami, Shigeyuki Nakaji, Hirotake Sakuraba, and Shinsaku Fukuda
- Subjects
liver fibrosis ,oral microbiota ,gut microbiota ,FibroScan–asparate aminotransferase (FAST) score ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The association between liver fibrosis and oral or gut microbiota has been studied before. However, epidemiological studies in the general population are limited owing to the difficulty of noninvasive liver-fibrosis assessment. FibroScan–asparate aminotransferase (FAST) scores can be used to accurately and non-invasively evaluate liver fibrosis. This study aimed to determine the association between liver fibrosis and oral or gut microbiota using the FAST score in the general population. After propensity score matching of 1059 participants based on sex, age, body mass index, homeostasis model assessment of insulin resistance, and triglyceride levels, 125 (non-liver-fibrosis group, 100; liver fibrosis group, 25) were included. The diversity of gut microbiota differed significantly between the two groups; however, no significant differences were noted in their oral microbiota. The liver fibrosis group showed an increase in the relative abundance of Fusobacteria strains and a decrease in the relative abundance of Faecalibacterium, with the presence of Fusicatenibacter in the gut microbiota. Feacalibacterium was not identified as an independent factor of liver fibrosis in adjusting the fatty liver index. In the general population, gut microbiota may be more involved in liver fibrosis than oral microbiota.
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- 2023
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22. Zinc Iodide-Metal Chloride-Organic Base: An Efficient Catalytic System for Synthesis of Cyclic Carbonates from Carbon Dioxide and Epoxides under Ambient Conditions
- Author
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Masatoshi Mihara, Shuichi Nakao, Takeo Nakai, and Takumi Mizuno
- Subjects
carbon dioxide ,epoxides ,cyclic carbonates ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Development of an effective catalytic system for the cycloaddition of carbon dioxide to epoxides for the preparation of cyclic carbonates under mild conditions is of great importance. Herein, a mixture of zinc iodide, metal chlorides, and strong organic bases is demonstrated to be a useful catalytic system that works at room temperature under atmospheric pressure. The most efficient combination, zinc iodide-niobium chloride-7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (1.2-0.3-3.0 mol%), gave styrene carbonate (95%) from styrene oxide and CO2 (balloon) at 25 °C for 24 h. Another combination, zinc iodide-zinc chloride-1,8-diazabicyclo[5.4.0]undec-7-ene (1.2-0.8-4.0 mol%), kept the catalytic activity for the preparation of propylene carbonate until the fourth run. Therefore, the reaction system was operationally simple, highly efficient, and proceeded under ambient conditions. The catalyst is composed of readily available reagents and is reusable. Thus, the method presented is a powerful tool for utilizing CO2 as the starting material for the production of valuable chemicals.
- Published
- 2023
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23. Evaluation of Lens Doses among Medical Staff Involved in Nuclear Medicine: Current Eye Radiation Exposure among Nuclear-Medicine Staff
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Masaki Fujisawa, Yoshihiro Haga, Masahiro Sota, Mitsuya Abe, Yuji Kaga, Yohei Inaba, Masatoshi Suzuki, Taiichiro Meguro, Yoshio Hosoi, and Koichi Chida
- Subjects
radiation protection and safety ,nuclear medicine ,positron emission tomography (PET) ,radioisotope (RI) examination ,single-photon emission computed tomography (SPECT) ,eye-lens dose ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The International Commission on Radiological Protection has lowered the annual equivalent eye-lens dose to 20 mSv. Although occupational exposure can be high in nuclear medicine (NM) departments, few studies have been conducted regarding eye-lens exposure among NM staff. This study aimed to estimate the annual lens doses of staff in an NM department and identify factors contributing to lens exposure. Four nurses and six radiographers performing positron emission tomography (PET) examinations and four radiographers performing radioisotope (RI) examinations (excluding PET) were recruited for this study. A lens dosimeter was attached near the left eye to measure the 3-mm-dose equivalent; a personal dosimeter was attached to the left side of the neck to measure the 1-cm- and 70-µm-dose equivalents. Measurements were acquired over six months, and the cumulative lens dose was doubled to derive the annual dose. Correlations between the lens and personal-dosimeter doses, between the lens dose and the numbers of procedures, and between the lens dose and the amounts of PET drugs (radiopharmaceuticals) injected were examined. Wilcoxon’s signed-rank test was used to compare lens and personal-dosimeter doses. The estimated annual doses were 0.93 ± 0.13 mSv for PET nurses, 0.71 ± 0.41 mSv for PET radiographers, and 1.10 ± 0.53 mSv for RI radiographers. For PET nurses, but not for PET or RI radiographers, there was a positive correlation between the numbers of procedures and lens doses and between amounts injected and lens doses. There was a significant difference between the lens and personal-dosimeter doses of PET nurses. The use of protective measures, such as shielding, should prevent NM staff from receiving lens doses > 20 mSv/year. However, depending on the height of the protective shield, PET nurses may be unable to assess the lens dose accurately using personal dosimeters.
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- 2023
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24. Small Molecules with Thiourea Skeleton Induce Ethylene Response in Arabidopsis
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Tomoyuki Koyama, Honami Zaizen, Ikuo Takahashi, Hidemitsu Nakamura, Masatoshi Nakajima, and Tadao Asami
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plant hormone ,ethylene mimic ,triple response ,thiourea ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Ethylene is the only gaseous plant hormone that regulates several aspects of plant growth, from seedling morphogenesis to fruit ripening and organ senescence. Ethylene also stimulates the germination of Striga hermonthica, a root parasitic weed that severely damages crops in sub-Saharan Africa. Thus, ethylene response stimulants can be used as weed and crop control agents. Ethylene and ethephon, an ethylene-releasing compound, are currently used as ethylene response inducers. However, since ethylene is a gas, which limits its practical application, we targeted the development of a solid ethylene response inducer that could overcome this disadvantage. We performed chemical screening using Arabidopsis thaliana “triple response” as an indicator of ethylene response. After screening, we selected a compound with a thiourea skeleton and named it ZKT1. We then synthesized various derivatives of ZKT1 and evaluated their ethylene-like activities in Arabidopsis. Some derivatives showed considerably higher activity than ZKT1, and their activity was comparable to that of 1-aminocyclopropane-1-carboxylate. Mode of action analysis using chemical inhibitors and ethylene signaling mutants revealed that ZKT1 derivatives activate the ethylene signaling pathway through interactions with its upstream components. These thiourea derivatives can potentially be potent crop-controlling chemicals.
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- 2023
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25. Inhibitory Effect of Adsorption of Streptococcus mutans onto Scallop-Derived Hydroxyapatite
- Author
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Momoko Usuda, Mariko Kametani, Masakazu Hamada, Yuto Suehiro, Saaya Matayoshi, Rena Okawa, Shuhei Naka, Michiyo Matsumoto-Nakano, Tatsuya Akitomo, Chieko Mitsuhata, Kazuya Koumoto, Keiko Kawauchi, Takahito Nishikata, Masatoshi Yagi, Toshiro Mizoguchi, Koki Fujikawa, Taizo Taniguchi, Kazuhiko Nakano, and Ryota Nomura
- Subjects
scallop-derived hydroxyapatite ,Streptococcus mutans ,adsorption ,RNA sequence ,bacterial growth ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Hydroxyapatite adsorbs various substances, but little is known about the effects on oral bacteria of adsorption onto hydroxyapatite derived from scallop shells. In the present study, we analyzed the effects of adsorption of Streptococcus mutans onto scallop-derived hydroxyapatite. When scallop-derived hydroxyapatite was mixed with S. mutans, a high proportion of the bacterial cells adsorbed onto the hydroxyapatite in a time-dependent manner. An RNA sequencing analysis of S. mutans adsorbed onto hydroxyapatite showed that the upregulation of genes resulted in abnormalities in pathways involved in glycogen and histidine metabolism and biosynthesis compared with cells in the absence of hydroxyapatite. S. mutans adsorbed onto hydroxyapatite was not killed, but the growth of the bacteria was inhibited. Electron microscopy showed morphological changes in S. mutans cells adsorbed onto hydroxyapatite. Our results suggest that hydroxyapatite derived from scallop shells showed a high adsorption ability for S. mutans. This hydroxyapatite also caused changes in gene expression related to the metabolic and biosynthetic processes, including the glycogen and histidine of S. mutans, which may result in a morphological change in the surface layer and the inhibition of the growth of the bacteria.
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- 2023
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26. Infection-Related Cryoglobulinemic Glomerulonephritis with Serum Anti-Factor B Antibodies Identified and Staining for NAPlr/Plasmin Activity Due to Infective Endocarditis
- Author
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Takumi Toishi, Takashi Oda, Atsuro Hamano, Shinnosuke Sugihara, Tomohiko Inoue, Atsuro Kawaji, Kanako Nagaoka, Masatoshi Matsunami, Junko Fukuda, Mamiko Ohara, and Tomo Suzuki
- Subjects
cryoglobulinemic glomerulonephritis ,infection-related glomerulonephritis ,factor B ,nephritis-associated plasmin receptor (NAPlr) ,infective endocarditis ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
In this rare case of infection-related cryoglobulinemic glomerulonephritis with infective endocarditis, a 78-year-old male presented with an acute onset of fever and rapidly progressive glomerulonephritis. His blood culture results were positive for Cutibacterium modestum, and transesophageal echocardiography showed vegetation. He was diagnosed with endocarditis. His serum immunoglobulin M, IgM-cryoglobulin, and proteinase-3-anti-neutrophil cytoplasmic antibody levels were elevated, and his serum complement 3 (C3) and C4 levels were decreased. Renal biopsy results showed endocapillary proliferation, mesangial cell proliferation, and no necrotizing lesions on light microscopy, with strong positive staining for IgM, C3, and C1q in the capillary wall. Electron microscopy showed deposits in the mesangial area in the form of fibrous structures without any humps. Histological examination confirmed a diagnosis of cryoglobulinemic glomerulonephritis. Further examination showed the presence of serum anti-factor B antibodies and positive staining for nephritis-associated plasmin receptor and plasmin activity in the glomeruli, suggesting infective endocarditis-induced cryoglobulinemic glomerulonephritis.
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- 2023
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27. Promotion Effects of Ultrafine Bubbles/Nanobubbles on Seed Germination
- Author
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Seiichi Oshita, Surina Boerzhijin, Hiromi Kameya, Masatoshi Yoshimura, and Itaru Sotome
- Subjects
ultrafine bubbles (UFBs) ,nanobubbles ,seed germination promotion ,ROS ,ESR ,Chemistry ,QD1-999 - Abstract
The number concentrations of air UFBs were controlled, approximately, by adjusting the generation time. UFB waters, ranging from 1.4 × 108 mL−1 to 1.0 × 109 mL−1, were prepared. Barley seeds were submerged in beakers filled with distilled water and UFB water in a ratio of 10 mL of water per seed. The experimental observations of seed germination clarified the role of UFB number concentrations; that is, a higher number concentration induced earlier seed germination. In addition, excessively high UFB number concentrations caused suppression of seed germination. A possible reason for the positive or negative effects of UFBs on seed germination could be ROS generation (hydroxyl radicals and ∙OH, OH radicals) in UFB water. This was supported by the detection of ESR spectra of the CYPMPO-OH adduct in O2 UFB water. However, the question still remains: how can OH radicals be generated in O2 UFB water?
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- 2023
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28. Evaluation of Friction Durability of Extremely Thin Diamond-Like Carbon Films by Statistical Cluster and Regression Analyses of Friction Coefficient
- Author
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Shojiro Miyake and Masatoshi Miyake
- Subjects
diamond-like carbon ,extremely thin film ,high-temperature tribological durability ,film substrate ,statistical cluster analysis of frictioncoefficient ,Physics ,QC1-999 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Mechanical engineering and machinery ,TJ1-1570 ,Chemistry ,QD1-999 - Abstract
We studied the tribological properties of extremely thin DLC films at high temperature. The films were deposited on nickel phosphorus (NiP) or Si substrates using filtered cathodic vacuum arc (FCVA) or plasma chemical vapor deposition (P-CVD). The nanoindentation hardness values and elastic moduli of the films were lower on NiP than on Si. The nanofriction force of the FCVA-DLC film on NiP was low at room temperature, but very high at high temperature. In this hard film, the lubricous adsorbate was removed by sliding at high temperature, making it easily damaged through the large deformation of NiP. In contrast, the friction force of the P-CVD-DLC films on both substrates was low at high temperatures. In this case, the lubricous tribochemical products from the P-CVD-DLC film reduced friction and wear. The friction map dependences on load and number of reciprocating cycles were evaluated using a friction test and statistical cluster analysis. The friction durability of both films depended more strongly on load on NiP than on Si, with the friction coefficients on Si being almost independent of load. At high temperatures and load, the durability of the FCVA-DLC film on NiP decreased and this film was easily damaged.
- Published
- 2021
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29. Simple Approach for Fluorescence Signal Amplification Utilizing a Poly(vinyl alcohol)-Based Polymer Structure in a Microchannel
- Author
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Keine Nishiyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Hideaki Hisamoto, and Manabu Tokeshi
- Subjects
Chemistry ,QD1-999 - Published
- 2021
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30. Polarization Raman Imaging of Organic Monolayer Islands for Crystal Orientation Analysis
- Author
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Toki Moriyama, Takayuki Umakoshi, Yoshiaki Hattori, Koki Taguchi, Prabhat Verma, and Masatoshi Kitamura
- Subjects
Chemistry ,QD1-999 - Published
- 2021
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31. Recycled Carbon Fibers with Improved Physical Properties Recovered from CFRP by Nitric Acid
- Author
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Asuka Sakai, Winarto Kurniawan, and Masatoshi Kubouchi
- Subjects
CFRP ,carbon fiber ,closed loop recycling ,epoxy resin ,nitric acid ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
To effectively reuse a large amount of Carbon Fiber Reinforced Plastics (CFRP) waste, the carbon fibers should be able to be recovered without degrading their quality. In this report, we developed a new approach to recover carbon fibers from CFRPs with improved physical properties compared to virgin carbon fibers with an environmentally friendly recycling method using nitric acid. Following the decomposition of the CFRP waste in nitric acid at 80 °C, both recycled carbon fibers and decomposed resin were recovered. The obtained recycled carbon fibers showed 1.4 times higher tensile strength and 2.2 times higher interfacial shear strength to resin compared to virgin carbon fibers. TEM-EDX analysis showed a decrease in the abundance of voids existing in the carbon fiber surface layer and new polar functional groups caused by nitric acid existing inside the voids, leading to increased tensile strength. Furthermore, XPS analysis showed that the interfacial shear strength improved due to the formation of new polar functional groups due to nitric acid. The possibility of applying recycled carbon fibers to CFRP products was shown by elucidating the mechanism that expressed its physical properties during the recycling process, leading to a novel approach to realizing closed-loop recycling.
- Published
- 2023
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32. New Insights into the Regulation of mTOR Signaling via Ca2+-Binding Proteins
- Author
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Yuna Amemiya, Masatoshi Maki, Hideki Shibata, and Terunao Takahara
- Subjects
mTOR ,Ca2+ mobilization ,calmodulin ,TSC2 ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Environmental factors are important regulators of cell growth and proliferation. Mechanistic target of rapamycin (mTOR) is a central kinase that maintains cellular homeostasis in response to a variety of extracellular and intracellular inputs. Dysregulation of mTOR signaling is associated with many diseases, including diabetes and cancer. Calcium ion (Ca2+) is important as a second messenger in various biological processes, and its intracellular concentration is tightly regulated. Although the involvement of Ca2+ mobilization in mTOR signaling has been reported, the detailed molecular mechanisms by which mTOR signaling is regulated are not fully understood. The link between Ca2+ homeostasis and mTOR activation in pathological hypertrophy has heightened the importance in understanding Ca2+-regulated mTOR signaling as a key mechanism of mTOR regulation. In this review, we introduce recent findings on the molecular mechanisms of regulation of mTOR signaling by Ca2+-binding proteins, particularly calmodulin (CaM).
- Published
- 2023
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33. Simple Detection and Culture of Circulating Tumor Cells from Colorectal Cancer Patients Using Poly(2-Methoxyethyl Acrylate)-Coated Plates
- Author
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Masatoshi Nomura, Yuhki Yokoyama, Daishi Yoshimura, Yasuhisa Minagawa, Aki Yamamoto, Yukiko Tanaka, Naoko Sekiguchi, Daiki Marukawa, Momoko Ichihara, Hiroaki Itakura, Kenichi Matsumoto, Yoshihiro Morimoto, Hideo Tomihara, Akira Inoue, Takayuki Ogino, Norikatsu Miyoshi, Hidekazu Takahashi, Hidenori Takahashi, Mamoru Uemura, Shogo Kobayashi, Tsunekazu Mizushima, Takahisa Anada, Masaki Mori, Yuichiro Doki, Masaru Tanaka, Hidetoshi Eguchi, and Hirofumi Yamamoto
- Subjects
CTC ,colorectal cancer ,PMEA ,cell culture ,spheroid ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Here we aimed to establish a simple detection method for detecting circulating tumor cells (CTCs) in the blood sample of colorectal cancer (CRC) patients using poly(2-methoxyethyl acrylate) (PMEA)-coated plates. Adhesion test and spike test using CRC cell lines assured efficacy of PMEA coating. A total of 41 patients with pathological stage II–IV CRC were enrolled between January 2018 and September 2022. Blood samples were concentrated by centrifugation by the OncoQuick tube, and then incubated overnight on PMEA-coated chamber slides. The next day, cell culture and immunocytochemistry with anti-EpCAM antibody were performed. Adhesion tests revealed good attachment of CRCs to PMEA-coated plates. Spike tests indicated that ~75% of CRCs from a 10-mL blood sample were recovered on the slides. By cytological examination, CTCs were identified in 18/41 CRC cases (43.9%). In cell cultures, spheroid-like structures or tumor-cell clusters were found in 18/33 tested cases (54.5%). Overall, CTCs and/or growing circulating tumor cells were found in 23/41 CRC cases (56.0%). History of chemotherapy or radiation was significantly negatively correlated with CTC detection (p = 0.02). In summary, we successfully captured CTCs from CRC patients using the unique biomaterial PMEA. Cultured tumor cells will provide important and timely information regarding the molecular basis of CTCs.
- Published
- 2023
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34. Real-Time Measurement of Protein Crystal Growth Rates within the Microfluidic Device to Understand the Microspace Effect
- Author
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Masatoshi Maeki, Shohei Yamazaki, Reo Takeda, Akihiko Ishida, Hirofumi Tani, and Manabu Tokeshi
- Subjects
Chemistry ,QD1-999 - Published
- 2020
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35. Facile Hydrogenative Deprotection of N‑Benzyl Groups Using a Mixed Catalyst of Palladium and Niobic Acid-on-Carbon
- Author
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Yuta Yamamoto, Eisho Shimizu, Kazuho Ban, Yoshiyuki Wada, Tomoteru Mizusaki, Masatoshi Yoshimura, Yukio Takagi, Yoshinari Sawama, and Hironao Sajiki
- Subjects
Chemistry ,QD1-999 - Published
- 2020
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36. Rules of Heliogeomagnetics Diversely Coordinating Biological Rhythms and Promoting Human Health
- Author
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Kuniaki Otsuka, Germaine Cornelissen, Andi Weydahl, Denis Gubin, Larry A. Beaty, and Masatoshi Murase
- Subjects
ambulatory blood-pressure monitoring ,cardiovascular circadian rhythm ,circadian amplitude ,circadian acrophase ,circasemidian (about 12 h) rhythm ,bell-shaped dose-response ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This investigation reviews how geomagnetic activity affects the circadian variation in blood pressure (BP) and heart rate (HR) and their variabilities of clinically healthy individuals. A small study in Alta, Norway (latitude of 70.0° N), serves to illustrate the methodology used to outline rules of procedure in exploring heliogeomagnetic effects on human physiology. Volunteers in the Alta study were monitored for at least 2 days between 18 March 2002 and 9 January 2005. Estimates of the circadian characteristics of BP and HR by cosinor and the Maximum Entropy Method (MEM) indicate an increase in the circadian amplitude of systolic (S) BP on geomagnetic-disturbance days compared to quiet days (p = 0.0236). Geomagnetic stimulation was found to be circadian-phase dependent, with stimulation in the evening inducing a 49.2% increase in the circadian amplitude of SBP (p = 0.0003), not observed in relation to stimulation in the morning. In two participants monitored for 7 days, the circadian amplitude of SBP decreased by 23.4% on an extremely disturbed day but increased by 50.3% on moderately disturbed days (p = 0.0044), suggesting a biphasic (hormetic) reaction of the circadian SBP rhythm to geomagnetics. These results indicate a possible role of geomagnetic fluctuations in modulating the circadian system.
- Published
- 2023
- Full Text
- View/download PDF
37. Antiandrogenic Effects of a Polyphenol in Carex kobomugi through Inhibition of Androgen Synthetic Pathway and Downregulation of Androgen Receptor in Prostate Cancer Cell Lines
- Author
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Yudai Kudo, Satoshi Endo, Masatoshi Tanio, Tomofumi Saka, Rin Himura, Naohito Abe, Mitsumi Takeda, Eiji Yamaguchi, Yuta Yoshino, Yuki Arai, Hirohito Kashiwagi, Masayoshi Oyama, Akichika Itoh, Masaki Shiota, Naohiro Fujimoto, and Akira Ikari
- Subjects
androgen receptor ,DHRS11 ,prostate cancer ,polyphenol ,Carex kobomugi ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Prostate cancer (PC) represents the most common cancer disease in men. Since high levels of androgens increase the risk of PC, androgen deprivation therapy is the primary treatment; however this leads to castration-resistant PC (CRPC) with a poor prognosis. The progression to CRPC involves ectopic androgen production in the adrenal glands and abnormal activation of androgen signaling due to mutations and/or amplification of the androgen receptor (AR) as well as activation of androgen-independent proliferative pathways. Recent studies have shown that adrenal-derived 11-oxygenated androgens (11-ketotestosterone and 11-ketodihydrotestosterone) with potencies equivalent to those of traditional androgens (testosterone and dihydrotestosterone) are biomarkers of CRPC. Additionally, dehydrogenase/reductase SDR family member 11 (DHRS11) has been reported to be a 17β-hydroxysteroid dehydrogenase that catalyzes the production of the 11-oxygenated and traditional androgens. This study was conducted to evaluate the pathophysiological roles of DHRS11 in PC using three LNCaP, C4-2 and 22Rv1 cell lines. DHRS11 silencing and inhibition resulted in suppression of the androgen-induced expression of AR downstream genes and decreases in the expression of nuclear AR and the proliferation marker Ki67, suggesting that DHRS11 is involved in androgen-dependent PC cell proliferation. We found that 5,7-dihydroxy-8-methyl-2-[2-(4-hydroxyphenyl)ethenyl]-4H-1-benzopyran-4-one (Kobochromone A, KC-A), an ingredient in the flowers of Carex kobomugi, is a novel potent DHRS11 inhibitor (IC50 = 0.35 μM). Additionally, KC-A itself decreased the AR expression in PC cells. Therefore, KC-A suppresses the androgen signaling in PC cells through both DHRS11 inhibition and AR downregulation. Furthermore, KC-A enhanced the anticancer activity of abiraterone, a CRPC drug, suggesting that it may be a potential candidate for the development of drugs for the prevention and treatment of CRPC.
- Published
- 2022
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38. Dry Printing of Ag–Ni Conductive Particles Using Toner-Type Printed Electronics
- Author
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Fumiya Sawamura, Chen Yi Ngu, Raiki Hanazaki, Kaito Kozuki, Sayaka Kado, Masatoshi Sakai, and Kazuhiro Kudo
- Subjects
printed electronics ,flexible electronics ,additive manufacturing ,conductive nanoparticle ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Printed electronics are a set of additive manufacturing methods for creating future flexible electronics on thin polymeric sheets. We proposed the toner-type, dry, page-printing of Ag–Ni composite conductive particles on flexible plastic sheets without pre-treatment. No chemical solvents are necessary to compose the inks of the electronic materials used for the toner-type printing, and no chemical treatment is required for the plastic film substrate surface. In addition, multilayer printing is simple when using toner printing because previously printed materials do not need to be resolved; furthermore, composing the thick films of the electronic materials is relatively simple. In this study, we fabricated an Ag–Ni composite toner to improve the fluidity of the toner particles compared to bare Ag particles. We successfully printed IC peripheral circuits at a resolution of 0.20 mm and demonstrated that the actual electrical circuit pattern can be formed using our method.
- Published
- 2022
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39. Rapid, Sensitive, and Selective Detection of H5 Hemagglutinin from Avian Influenza Virus Using an Immunowall Device
- Author
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Kenia Chávez Ramos, Keine Nishiyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Toshihiro Kasama, Yoshinobu Baba, and Manabu Tokeshi
- Subjects
Chemistry ,QD1-999 - Published
- 2019
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40. Birch-Type Reduction of Arenes in 2‑Propanol Catalyzed by Zero-Valent Iron and Platinum on Carbon
- Author
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Yoshinari Sawama, Kazuho Ban, Kazuhiro Akutsu-Suyama, Hiroki Nakata, Misato Mori, Tsuyoshi Yamada, Takahiro Kawajiri, Naoki Yasukawa, Kwihwan Park, Yasunari Monguchi, Yukio Takagi, Masatoshi Yoshimura, and Hironao Sajiki
- Subjects
Chemistry ,QD1-999 - Published
- 2019
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41. Separation of Pb(II) Ion with Tetraacetic Acid Derivative of Calix[4]arene by Using Droplet-based Microreactor System
- Author
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Yehezkiel Steven Kurniawan, Mizuki Ryu, Ramachandra Rao Sathuluri, Wataru Iwasaki, Shintaro Morisada, Hidetaka Kawakita, Keisuke Ohto, Masatoshi Maeki, Masaya Miyazaki, and Jumina Jumina
- Subjects
microreactor ,Pb(II) extraction ,separation ,calix[4]arene ,Chemistry ,QD1-999 - Abstract
In this study, the microreactor system was investigated and compared with the batch-wise system as rapid and effective extractive Pb(II) separation over Fe(III), Cu(II) and Zn(II) with tetraacetic acid calix[4]arene. By using a microreactor system, the Pb(II) extraction percentages reached the maximum of 73, 89 and 100% in 8 sec residence time at equilibrium pH of 2.00, 2.25 and 2.50, respectively. The stripping percentage was 92% at 8 sec residence time by using a microreactor system with 2.0 M HNO3 as a stripping reagent. Complete separation of Pb(II) over Fe(III), Cu(II) and Zn(II) ions with the tetraacetic acid calix[4]arene in a competitive metal system was achieved at pH 2.00. However, the batch system required 24 h to reach the equilibrium for both extraction and stripping processes. The results suggested that the microreactor system enhanced the Pb(II) extraction and stripping rate up to 104 times faster than the batch-wise system.
- Published
- 2019
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- View/download PDF
42. Elevated Alpha 1(I) to Alpha 2(I) Collagen Ratio in Dermal Fibroblasts Possibly Contributes to Fibrosis in Systemic Sclerosis
- Author
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Soichiro Sawamura, Katsunari Makino, Maho Ide, Shuichi Shimada, Ikko Kajihara, Takamitsu Makino, Masatoshi Jinnin, and Satoshi Fukushima
- Subjects
extracellular matrix ,fibroblast ,fibrosis ,metabolism ,systemic sclerosis ,type I collagen ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Systemic sclerosis (SSc) is characterized by excessive collagen deposition in the skin and internal organs. Activated fibroblasts are the key effector cells for the overproduction of type I collagen, which comprises the α1(I) and α2(I) chains encoded by COL1A1 and COL1A2, respectively. In this study, we examined the expression patterns of α1(I) and α2(I) collagen in SSc fibroblasts, as well as their co-regulation with each other. The relative expression ratio of COL1A1 to COL1A2 in SSc fibroblasts was significantly higher than that in control fibroblasts. The same result was observed for type I collagen protein levels, indicating that α2(I) collagen is more elevated than α2(I) collagen. Inhibition or overexpression of α1(I) collagen in control fibroblasts affected the α2(I) collagen levels, suggesting that α1(I) collagen might act as an upstream regulator of α2(I) collagen. The local injection of COL1A1 small interfering RNA in a bleomycin-induced SSc mouse model was found to attenuate skin fibrosis. Overall, our data indicate that α2(I) collagen is a potent regulator of type I collagen in SSc; further investigations of the overall regulatory mechanisms of type I collagen may help understand the aberrant collagen metabolism in SSc.
- Published
- 2022
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43. IL-17A Is the Critical Cytokine for Liver and Spleen Amyloidosis in Inflammatory Skin Disease
- Author
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Shohei Iida, Takehisa Nakanishi, Fumiyasu Momose, Masako Ichishi, Kento Mizutani, Yoshiaki Matsushima, Ai Umaoka, Makoto Kondo, Koji Habe, Yoshifumi Hirokawa, Masatoshi Watanabe, Yoichiro Iwakura, Yoshihiro Miyahara, Yasutomo Imai, and Keiichi Yamanaka
- Subjects
inflammatory skin ,mouse model ,dermatitis ,cytokine ,amyloidosis ,JAK inhibitor ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Systemic amyloidosis is recognized as a serious complication of rheumatoid arthritis or inflammatory bowel disease, but also of inflammatory skin disease. However, the detailed molecular mechanism of amyloidosis associated with cutaneous inflammation remains unclear, and therapeutic approaches are limited. Here, we investigated the pathophysiology of amyloidosis secondary to cutaneous inflammation and the therapeutic effects of Janus kinase (JAK) inhibitors by examining a mouse model of spontaneous dermatitis (KCASP1Tg mice). Moreover, KCASP1Tg mice were crossed with interleukin-17A (IL-17A) knockout mice to generate IL-17A-/KCASP1Tg and examine the role of IL-17A in amyloidosis under cutaneous inflammation. KCASP1Tg mice showed severe amyloid deposition in the liver and spleen. Increased serum-neutral fat levels and decreased lymphocyte production were observed in the spleen. Overproduction of amyloidosis was partially ameliorated by the administration of JAK inhibitors and was further improved in IL-17A-/KCASP1Tg mice. IL-17A-producing cells included CD4, gamma delta, and CD8 T cells. In summary, our results from the analysis of a mouse model of dermatitis revealed that skin-derived inflammatory cytokines can induce amyloid deposition in the liver and spleen, and that the administration of JAK inhibitors and, even more, IL-17A ablation, reduced amyloidosis. This study demonstrates that active control of skin inflammation is essential to prevent internal organ amyloidosis.
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- 2022
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44. High-Power Abiotic Direct Glucose Fuel Cell Using a Gold–Platinum Bimetallic Anode Catalyst
- Author
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Kanjiro Torigoe, Masatoshi Takahashi, Koji Tsuchiya, Kazuki Iwabata, Toshinari Ichihashi, Kengo Sakaguchi, Fumio Sugawara, and Masahiko Abe
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Chemistry ,QD1-999 - Published
- 2018
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45. Label-Free Electrochemical Sensor for Ochratoxin A Using a Microfabricated Electrode with Immobilized Aptamer
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Donny N. Mazaafrianto, Akihiko Ishida, Masatoshi Maeki, Hirofumi Tani, and Manabu Tokeshi
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Chemistry ,QD1-999 - Published
- 2018
- Full Text
- View/download PDF
46. PARP Inhibitor Decreases Akt Phosphorylation and Induces Centrosome Amplification and Chromosomal Aneuploidy in CHO-K1 Cells
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Masakazu Tanaka, Masatoshi Mushiake, Jun Takahashi, Yuka Sasaki, Sachiko Yamashita, Chieri Ida, Mitsuko Masutani, and Masanao Miwa
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Akt ,cell proliferation ,centrosome amplification ,chromosome aneuploidy ,PARP inhibitors ,polyADP-ribosylation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Cancer cells are known to have chromosomal number abnormalities (aneuploidy), a hallmark of malignant tumors. Cancer cells also have an increased number of centrosomes (centrosome amplification). Paradoxically, cancer therapies, including γ-irradiation and some anticancer drugs, are carcinogenic and can induce centrosome amplification and chromosomal aneuploidy. Thus, the processes of carcinogenesis and killing cancer cells might have some mechanisms in common. Previously, we found that the inhibitors of polyADP-ribosylation, a post-translational modification of proteins, caused centrosome amplification. However, the mechanism of action of the inhibitors of polyADP-ribosylation is not fully understood. In this study, we found that an inhibitor of polyADP-ribosylation, 3-aminobenzamide, caused centrosome amplification, as well as aneuploidy of chromosomes in CHO-K1 cells. Moreover, inhibitors of polyADP-ribosylation inhibited AKT phosphorylation, and inhibitors of AKT phosphorylation inhibited polyADP-ribosylation, suggesting the involvement of polyADP-ribosylation in the PI3K/Akt/mTOR signaling pathway for controlling cell proliferation. Our data suggest a possibility for developing drugs that induce centrosome amplification and aneuploidy for therapeutic applications to clinical cancer.
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- 2022
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47. Collection of Data Variation Using a High-Throughput Image-Based Assay Platform Facilitates Data-Driven Understanding of TRPA1 Agonist Diversity
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Yuko Terada, Kenjiro Tanaka, Minami Matsuyama, Masaya Fujitani, Masatoshi Shibuya, Yoshihiko Yamamoto, Ryuji Kato, and Keisuke Ito
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TRPA1 agonist ,image-based assay ,Ca2+ imaging ,chemical library ,physicochemical descriptors ,clustering ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Because transient receptor potential ankyrin 1 (TRPA1) is involved in various physiological functions, TRPA1-targeting drugs have been energetically developed. Although TRPA1 is considered a multimodal receptor, the structural diversity of TRPA1 agonists is not fully elucidated. We hypothesized that collecting a wider variation of TRPA1–compound interaction data would aid the understanding of its complex mechanism and aimed to challenge such data collection using an “image-based TRPA1 assay system combined with an in silico chemical space clustering concept.” Our library was clustered with 27 physicochemical molecular descriptors in silico, and structurally diverse compounds from each cluster were selected for a detailed kinetic assay to investigate variations of agonist structural rules. Through two sets of assays evaluating various compounds in parallel with validating effects of the previously established structural rules, we discovered that different chemical groups contribute to agonist activity, indicating that there are multiple agonist design concepts. A novel core structure for a TRPA1 agonist has been also proposed. Our new approach, “collection of TRPA1 activity data on compounds with physicochemical diversity,” will not only facilitate the understanding of the structural diversity of TRPA1 agonists but also contribute to the development of a new type of TRPA1-targeting drug.
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- 2022
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48. ISSVA Classification of Vascular Anomalies and Molecular Biology
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Kayo Kunimoto, Yuki Yamamoto, and Masatoshi Jinnin
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venous malformation ,lymphatic malformation ,infantile hemangioma ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Vascular anomalies include various diseases, which are classified into two types according to the International Society for the Study of Vascular Anomalies (ISSVA) classification: vascular tumors with proliferative changes of endothelial cells, and vascular malformations primarily consisting of structural vascular abnormalities. The most recent ISSVA classifications, published in 2018, detail the causative genes involved in many lesions. Here, we summarize the latest findings on genetic abnormalities, with the presentation of the molecular pathology of vascular anomalies.
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- 2022
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49. Stress Dispersion Design in Continuum Compliant Structure toward Multi-DOF Endoluminal Forceps
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Keisuke Osawa, D. S. V. Bandara, Ryu Nakadate, Yoshihiro Nagao, Tomohiko Akahoshi, Masatoshi Eto, and Jumpei Arata
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design methodology ,finite element analysis ,medical robotics ,surgical instruments ,soft robotics ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Gastrointestinal cancer, when detected early, is treated by accessing the lesion through the natural orifice using flexible endoscopes. However, the limited degree-of-freedom (DOF) of conventional treatment devices and the narrow surgical view through the endoscope demand advanced techniques. In contrast, multi-DOF forceps systems are an excellent alternative; however, these systems often involve high fabrication costs because they require a large number of micro-parts. To solve this problem, we designed compact multi-DOF endoluminal forceps with a monolithic structure comprising compliant hinges. To allow an efficient stress dispersion at the base end when the hinge bends, we proposed a novel design method to obtain the hinge parameters using the beam of uniform strength theory. This method does not involve a high computational cost. The results show that the improved design with a variable hinge thickness can reduce the maximum bending stress, dispersing the stress in a larger area than that of the previous design considering a constant thickness of the hinge. Moreover, the experiments conducted in a prototype confirm that the radius of the curvature was significantly improved. The proposed method could aid in designing other continuum robots relying on compliant hinges.
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- 2022
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50. Development of the iLiNP Device: Fine Tuning the Lipid Nanoparticle Size within 10 nm for Drug Delivery
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Niko Kimura, Masatoshi Maeki, Yusuke Sato, Yusuke Note, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, and Manabu Tokeshi
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Chemistry ,QD1-999 - Published
- 2018
- Full Text
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