Publications by authors named "Amamoto Y"

Surface modification using hydrophilic polymer coatings is a sustainable approach for preventing membrane clogging due to foulant adhesion to water treatment membranes and reducing membrane-replacement frequency. Typically, both molecular descriptors and time-domain nuclear magnetic resonance (TD-NMR) data, which reveal physicochemical properties and polymer-chain dynamics, respectively, are required to predict the properties and understand the mechanisms of hydrophilic polymer coatings. However, studies on the selection of essential components from high-dimensional data and their application to the prediction of surface properties are scarce.

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Biopharmaceuticals, including therapeutic antibodies, are rapidly growing products in the pharmaceutical market. Mammalian cells, such as Chinese hamster ovary (CHO) cells, are widely used as production hosts because recombinant antibodies require complex three-dimensional structures modified with sugar chains. Recombinant protein production using mammalian cells is generally performed with cell growth.

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Article Synopsis
  • CHO cells are now the standard for producing therapeutic antibodies due to their high production yield requirements.
  • This study focuses on creating a new gene expression system using an artificial transcription factor to enhance gene expression in CHO cells for better antibody production.
  • The researchers successfully produced a model antibody, achieving impressive results in both plate-scale and continuous bioreactor cultures, with antibodies reaching concentrations of up to 5.5 g/L.
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Binary alloy catalysts have the potential to exhibit higher activity than monometallic catalysts in nitrogen activation reactions. However, owing to the multiple possible combinations of metal elements constituting binary alloys, an exhaustive search for the optimal combination is difficult. In this study, we searched for the optimal binary alloy catalyst for nitrogen activation reactions using a combination of Bayesian optimization and density functional theory calculations.

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The complicated structure-property relationships of materials have recently been described using a methodology of data science that is recognized as the fourth paradigm in materials science. In network polymers or elastomers, the manner of connection of the polymer chains among the crosslinking points has a significant effect on the material properties. In this study, we quantitatively evaluate the structural heterogeneity of elastomers at the mesoscopic scale based on complex network, one of the methods used in data science, to describe the elastic properties.

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Lysine acylation of proteins is a crucial chemical reaction, both as a post-translational modification and as a method for bioconjugation. We previously developed a chemical catalyst, DSH, which activates a chemically stable thioester including acyl-CoA, allowing the site-selective lysine acylation of histones under physiological conditions. However, a more active catalyst is required for efficient lysine acylation in more complex biological milieu, such as in living cells, but there are no rational guidelines for developing efficient lysine acylation catalysts for use under physiological conditions as opposed to in organic solvents.

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Although it has not been frequently discussed, contributions of the orientational cross-correlation (OCC) between entangled polymers are not negligible in the relaxation modulus. In the present study, OCC contributions were investigated for 4- and 6-arm star-branched and H-branched polymers by means of multi-chain slip-link simulations. Owing to the molecular-level description of the simulation, the segment orientation was traced separately for each molecule as well as each subchain composing the molecules.

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Probe rheology experiments, in which the dynamics of a small amount of probe chains dissolved in immobile matrix chains is discussed, have been performed for the development of molecular theories for entangled polymer dynamics. Although probe chain dynamics in probe rheology is considered hypothetically as single chain dynamics in fixed tube-shaped confinement, it has not been fully elucidated. For instance, the end-to-end relaxation of probe chains is slower than that for monodisperse melts, unlike the conventional molecular theories.

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Posttranslational modifications (PTMs) of histones play an important role in the complex regulatory mechanisms governing gene transcription, and their dysregulation can cause diseases such as cancer. The lack of methods for site-selectively modifying native chromatin, however, limits our understanding of the functional roles of a specific histone PTM, not as a single mark, but in the intertwined PTM network. Here, we report a synthetic catalyst DMAP-SH (DSH), which activates chemically stable thioesters (including acetyl-CoA) under physiological conditions and transfers various acyl groups to the proximate amino groups.

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The purpose of this study was to compare metabolic costs, rating of perceived exertion (RPE), and stride frequency during backward walking in water and on land. The walking speeds in water were set to be half of those on land. There was no significant difference in metabolic costs and RPE between backward walking in water with a current and on land, at slow and moderate speeds (P > 0.

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Self-healing of covalently cross-linked polymers under an ambient visible light in the bulk state, in air, at room temperature using radical exchange of thiuram disulfide units is reported. The successful attachment of surfaces of cut pieces proceeded under ambient conditions under exposure to visible light from a commercial tabletop lamp, as confirmed by bending and tensile tests.

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Changes in the structure of networks of chemical gels cross-linked by covalent bonds have been investigated using reshuffling (i.e., degenerative exchange) reactions of the covalent bonds.

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Objective: The purposes of this study were 1) to re-examine effects obtained from previous research of a non-face-to-face behavioral intervention in poorer sleepers and 2) to examine the factors impacting on improvement of sleep.

Methods: The subjects were 178 poor sleepers who participated in an intervention for sleep improvement. The educational procedures comprised a minimal behavioral self-help package for one month that featured self- learning and self- monitoring of practical target habits for change.

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The formation of star-like nanogels with different arm lengths via a radical crossover reaction of alkoxyamine units in diblock copolymers and direct observation of the star-like nanogels by scanning force microscopy were successfully accomplished.

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We compared physiological and perceptual responses, and stride characteristics while walking backward in water with those of walking forward in water. Eight males walked on an underwater treadmill, immersed to their xiphoid process level. Oxygen uptake ((.

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Programmed thermodynamic formation of star-like nanogels from designed diblock copolymers with thermally exchangeable dynamic covalent bonds in their side chains and structure analysis of the nanogels were performed. Linear diblock copolymers that consist of poly(methyl methacrylate) block and random copolymer block of methyl methacrylate (MMA) and methacrylic esters with alkoxyamine moiety were prepared by atom transfer radical polymerization (ATRP). By heating the diblock copolymers in anisole, a cross-linking reaction occurred as a result of the radical crossover reaction of alkoxyamine moieties to afford star-like nanogels.

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Two cases of primary small bowel volvulus in neonates are presented. On abdominal plain radiographs pseudotumor sign was seen in both cases. CT showed intensely distended fluid-filled small bowel loops on the right side of the abdomen and diffuse distention of the proximal small bowel loops with air-fluid levels.

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We retrospectively analyzed CT scans from 23 patients with non-traumatic colorectal perforation. We compared the sensitivity of CT and plain film radiography in the detection of free gas. Free gas was observed in 7 of the 23 cases (30.

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This study was conducted to evaluate longitudinal changes in the peritoneal equilibration test (PET) in children treated with continuous peritoneal dialysis (CPD). The effects of prolonged CPD and episodes of peritonitis on the PET were examined. PET was repeated up to five times in 12 paediatric patients who were subdivided into groups with and without peritonitis.

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We present a 1-month-old girl with a congenital nephrotic syndrome and unusual histological findings. Immunofluorescence microscopy demonstrated granular mesangial deposition of C1q and electron microscopy revealed electron-dense mesangial deposits. Her heavy proteinuria gradually decreased and the steroid therapy did not have a significant effect.

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