512 results match your criteria: "Riken (The Institute of Physical and Chemical Research)[Affiliation]"

Inhibitory Effects of Cryptotanshinone and Dihydrotanshinone I on Intracellular Trafficking of Viral Glycoproteins.

J Microbiol Biotechnol

December 2024

Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju 63243, Republic of Korea.

Antiviral agents that target the viral envelope surface glycoproteins can disrupt the interactions between the viral glycoproteins and host cell receptors, thereby preventing viral entry into host cells. However, the mechanisms underlying glycoprotein processing and cellular trafficking have not been fully elucidated. In this study, we aimed to investigate the mechanism of action of cryptotanshinone (CTN) and dihydrotanshinone I (DTN) as inhibitors of viral glycoprotein trafficking, by assessing their inhibitory action on syncytium formation and cytopathic effects.

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Comparative Conformational Analysis of Acyclic Sugar Alcohols Ribitol, Xylitol and d-Arabitol by Solution NMR and Molecular Dynamics Simulations.

Molecules

February 2024

Division of Structural Biology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Miyagi, Japan.

Ribitol (CHO) is an acyclic sugar alcohol that was recently identified in -mannose glycan on mammalian α-dystroglycan. The conformation and dynamics of acyclic sugar alcohols such as ribitol are dependent on the stereochemistry of the hydroxyl groups; however, the dynamics are not fully understood. To gain insights into the conformation and dynamics of sugar alcohols, we carried out comparative analyses of ribitol, d-arabitol and xylitol by a crystal structure database search, solution NMR analysis and molecular dynamics (MD) simulations.

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Jellyfish (JF) mucin (precisely, a mucin-type glycoprotein named qniumucin: Q-mucin) first discovered in JF is mainly composed of highly O-glycosylated domains, and its unique structure suggests its wide applications as a smart material. In this study, the standard protocol used to date was thoroughly reinvestigated because the processing of raw JF was rather difficult and continuous production from frozen sources was also indispensable. Finally, we concluded that Q-mucin is involved not in mucus but in the mesoglea, i.

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In this study, the spatial counting statistics of free electron beams, which were released via field emission from cold metal and propagated through a vacuum region, were investigated to examine the normal functioning of the counting equipment for electron correlation spectroscopy. The beam electrons were recorded separately according to the locations of individual events as they reached the direct detection transmission Complementary Metal Oxide Semiconductor (CMOS) sensor. We examined the spatial point patterns arising from the locations of the individual events of each primary electron being detected in the case of electrons in a state in which the wave function is constant on the sensor.

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Ribitol in Solution Is an Equilibrium of Asymmetric Conformations.

Molecules

September 2021

Division of Structural Glycobiology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Miyagi, Japan.

Ribitol (CHO), an acyclic sugar alcohol, is present on mammalian α-dystroglycan as a component of -mannose glycan. In this study, we examine the conformation and dynamics of ribitol by database analysis, experiments, and computational methods. Database analysis reveals that the anti-conformation (180°) is populated at the C3-C4 dihedral angle, while the gauche conformation (±60°) is seen at the C2-C3 dihedral angle.

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Collagen is one of the most common materials used to form scaffolds for tissue engineering applications. The multi-channel collagen gel (MCCG) obtained by the dialysis of an acidic collagen solution in a neutral buffer solution has a unique structure, with many capillaries of diameters several tens to a few hundred micrometers, and could be a potential candidate as a biomimetic scaffold for three-dimensional tissue engineering. In the present study, the formation of MCCG was investigated by rheological measurements based on a particle tracking method (particle tracking microrheology, PTM).

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We have developed an amplitude-division type Mach-Zehnder electron interferometer (MZ-EI). The developed MZ-EI is composed of single crystals corresponding to amplitude-division beam splitters, lenses corresponding to mirrors and an objective aperture. The spacings and azimuth angles of interference fringes can be controlled by single crystal materials and their orientations and by diffraction spots selected by the objective aperture.

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This paper reviews the basics of electron holography as an introduction of the holography part of this special issue in Microscopy. We discuss the general principle of holography and interferometry regarding measurements and analyses of phase distributions, first using the optical holography. Next, we discuss physical phenomena peculiar to electron waves that cannot be realized by light waves and principles of electromagnetic field detection and observation methods.

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Lensless fourier transform electron holography applied to vortex beam analysis.

Microscopy (Oxf)

May 2020

Research and Development Group, Hitachi, Ltd., Hatoyama, Saitama 350-0395, Japan.

Lensless Fourier transform holography has been developed. By treating Bragg diffraction waves as object waves and a transmitted spherical wave as a reference wave, these two waves are interfered and recorded as holograms away from the reciprocal plane. In this method, reconstruction of holograms requires only one Fourier transform.

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Ovarian cancer survival is poor, in part, because there are no specific biomarkers for early diagnosis. C-Mannosyl tryptophan (CMW) is a structurally unique glycosylated amino acid recently identified as a novel biomarker of renal dysfunction. The present study investigated whether blood CMW is altered in patients with ovarian cancer and whether differences in blood CMW can distinguish benign from malignant ovarian tumors.

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C-Mannosyl tryptophan (C-Man-Trp) is a unique molecule in that an α-mannose is connected to the indole C2 carbon atom of a Trp residue via C-glycosidic linkage. Although serum C-Man-Trp may be a novel biomarker of renal function in humans, the biological significance of C-Man-Trp has yet to be fully investigated. In this study, a novel assay system for C-Man-Trp was established using hydrophilic-interaction liquid chromatography, followed by detecting the fluorescence intensity or mass abundance of C-Man-Trp.

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Electron holography in Fraunhofer region was realized by using an asymmetric double slit. A Fraunhofer diffraction wave from a wider slit worked as an objective wave interfered with a plane wave from a narrower slit as a reference wave under the pre-Fraunhofer condition and recorded as a hologram. Here, the pre-Fraunhofer condition means that the following conditions are simultaneously satisfied: single-slit observations are performed under the Fraunhofer condition and the double-slit observations are performed under the Fresnel condition.

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Phase 0 approaches, including microdosing, involve the use of sub-therapeutic exposures to the tested drugs, thus enabling safer, more-relevant, quicker and cheaper first-in-human (FIH) testing. These approaches also have considerable potential to limit the use of animals in human drug development. Recent years have witnessed progress in applications, methodology, operations, and drug development culture.

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Advanced electron microscopy technologies have made it possible to perform precise double-slit interference experiments. We used a 1.2-MV field emission electron microscope providing coherent electron waves and a direct detection camera system enabling single-electron detections at a sub-second exposure time.

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Stereoselective synthesis of the ent-ZA'B'C'D'-ring system of maitotoxin has been accomplished through a convergent strategy utilizing Suzuki-Miyaura cross coupling reaction of ZA'-ring alkylborane and C'D'-ring (Z)-vinyl iodide, and subsequent construction of the B'-ring by reduction of the O,S-acetal.

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Understanding the structural evolution of materials is a challenging problem of condensed matter physics. Solving this problem would open new ways for understanding the behaviors of materials. In this context, we here report unbiased structure searches for a prototypical perovskite oxide, PbTiO, based on the CALYPSO (Crystal structure AnaLYsis by Particle Swarm Optimization) method in conjunction with first-principles calculations.

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Effect of circulating tissue factor on hypercoagulability in type 2 diabetes mellitus studied by rheometry and dielectric blood coagulometry.

Biorheology

July 2017

LE Development Department, R&D Division, Medical Business Unit, Imaging Products & Solutions Sector, Sony Corporation, Tokyo, Japan.

Background: Hypercoagulability in type 2 diabetes mellitus (T2DM) patients increases their risk of cardiovascular diseases.

Objective: The aim of this work was to investigate the hypercoagulation mechanism in T2DM patients in terms of circulating tissue factor (TF).

Methods: Whole blood coagulation tests by damped oscillation rheometry and dielectric blood coagulometry (DBCM) were performed.

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Fatigue and Sleep Among Employees With Prospective Increase in Work Time Control: A 1-Year Observational Study With Objective Assessment.

J Occup Environ Med

November 2016

National Institute of Occupational Safety and Health (Drs Kubo, Takahashi, Liu, Ikeda), The University of Tokyo Graduate School of Education (Dr Togo), The University of Tokyo Graduate School of Medicine, Tokyo (Dr Shimazu), Graduate School of Medical Science, Kitasato University (Dr Tanaka), Department of Psychiatry, School of Medicine, Kitasato University, Sagamihara (Dr Kamata), School of Nursing, Faculty of Medicine, The Jikei University, Tokyo (Dr Kubo), and Occupational Health Center, Yokohama Branch, RIKEN (The Institute of Physical and Chemical Research), Yokohama, Japan (Uesugi).

Article Synopsis
  • This study observed how changes in work time control (WTC) over a year affect fatigue and sleep in employees.
  • Thirty-nine employees were split into two groups: one with increased WTC and one without, using tests to measure fatigue and sleep objectively.
  • Results showed that employees with increased WTC had better performance and sleep quality, indicating that greater control over work time may help reduce fatigue and improve sleep.
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Background: Japanese cedar (Cryptomeria japonica) pollinosis is the most prevalent seasonal rhinitis in Japan. A standardized Japanese cedar pollen extract (CPE) containing 1.5-4.

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Spectrum of allergens for Japanese cedar pollinosis and impact of component-resolved diagnosis on allergen-specific immunotherapy.

Allergol Int

October 2015

Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan. Electronic address:

The high prevalence of Japanese cedar pollinosis in Japan is associated with a negative impact on the quality of life of patients, as well as significant loss of productivity among the workforce in early spring, thus representing a serious social problem. Furthermore, the prevalence is increasing, and has risen by more than 10% in this decade. Cry j 1 and Cry j 2 were identified as the major allergens in Japanese cedar pollen (JCP), and in 2004, the existence of other major and minor allergens were revealed by a combination of two-dimensional electrophoresis and immunoblotting analysis.

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Tumor necrosis factor alpha (TNF-α), a central mediator of the inflammatory response, is released from basophilic cells and other cells in response to a variety of proinflammatory stimuli. Vialinin A is a potent inhibitor of TNF-α production and is released from RBL-2H3 cells. Ubiquitin-specific peptidase 5 (USP5), a deubiquitinating enzyme, was identified as a target molecule of vialinin A and its enzymatic activity was inhibited by vialinin A.

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Discovery of a disused desaturase gene from the pheromone gland of the moth Ascotis selenaria, which secretes an epoxyalkenyl sex pheromone.

Biochem Biophys Res Commun

November 2013

Graduate School of Bio-Applications and Systems Engineering (BASE), Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan; Molecular Entomology Laboratory, RIKEN (The Institute of Physical and Chemical Research), Wako, Saitama 351-0198, Japan; Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan. Electronic address:

Female Ascotis selenaria (Geometridae) moths use 3,4-epoxy-(Z,Z)-6,9-nonadecadiene, which is synthesized from linolenic acid, as the main component of their sex pheromone. While the use of dietary linolenic or linoleic fatty acid derivatives as sex pheromone components has been observed in moth species belonging to a few families including Geometridae, the majority of moths use derivatives of a common saturated fatty acid, palmitic acid, as their sex pheromone components. We attempted to gain insight into the differentiation of pheromone biosynthetic pathways in geometrids by analyzing the desaturase genes expressed in the pheromone gland of A.

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Zero-multipole summation method for efficiently estimating electrostatic interactions in molecular system.

J Chem Phys

November 2013

Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan and RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

The zero-multipole summation method has been developed to efficiently evaluate the electrostatic Coulombic interactions of a point charge system. This summation prevents the electrically non-neutral multipole states that may artificially be generated by a simple cutoff truncation, which often causes large amounts of energetic noise and significant artifacts. The resulting energy function is represented by a constant term plus a simple pairwise summation, using a damped or undamped Coulombic pair potential function along with a polynomial of the distance between each particle pair.

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Several non-Ewald methods for calculating electrostatic interactions have recently been developed, such as the Wolf method, the reaction field method, the pre-averaging method, and the zero-dipole summation method, for molecular dynamics simulations of various physical systems, including biomolecular systems. We review the theories of these approaches and their potential applications to molecular simulations, and discuss their relationships.

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The zero-dipole summation method was extended to general molecular systems, and then applied to molecular dynamics simulations of an isotropic water system. In our previous paper [I. Fukuda, Y.

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