Tohoku University

About: Tohoku University is a education organization based out in Sendai, Japan. It is known for research contribution in the topics: Magnetization & Population. The organization has 72116 authors who have published 170791 publications receiving 3941714 citations. The organization is also known as: Tōhoku daigaku.

Quantitative Atlas of Membrane Transporter Proteins: Development and Application of a Highly Sensitive Simultaneous LC/MS/MS Method Combined with Novel In-silico Peptide Selection Criteria

Abstract: Purpose To develop an absolute quantification method for membrane proteins, and to construct a quantitative atlas of membrane transporter proteins in the blood–brain barrier, liver and kidney of mouse.

Direct observation of local atomic order in a metallic glass

Abstract: The atomic configuration of metallic glasses is a long-standing issue important to the understanding of their properties Nanobeam electron diffraction experiments now enable a direct determination of the local atomic order in a metallic glass The determination of the atomic configuration of metallic glasses is a long-standing problem in materials science and solid-state physics1,2 So far, only average structural information derived from diffraction and spectroscopic methods has been obtained Although various atomic models have been proposed in the past fifty years3,4,5,6,7,8, a direct observation of the local atomic structure in disordered materials has not been achieved Here we report local atomic configurations of a metallic glass investigated by nanobeam electron diffraction combined with ab initio molecular dynamics simulation Distinct diffraction patterns from individual atomic clusters and their assemblies, which have been theoretically predicted as short- and medium-range order6,7,8, can be experimentally observed This study provides compelling evidence of the local atomic order in the disordered material and has important implications in understanding the atomic mechanisms of metallic-glass formation and properties

Cytoskeletal remodelling and slow dynamics in the living cell.

Abstract: The cytoskeleton (CSK) is a crowded network of structural proteins that stabilizes cell shape and drives cell motions. Recent studies on the dynamics of the CSK have established that a wide variety of cell types exhibit rheology in which responses are not tied to any particular relaxation times and are thus scale-free. Scale-free rheology is often found in a class of materials called soft glasses, but not all materials expressing scale-free rheology are glassy (see plastics, wood, concrete or some metals for example). As such, the extent to which dynamics of the CSK might be regarded as glassy remained an open question. Here we report both forced and spontaneous motions of microbeads tightly bound to the CSK of human muscle cells. Large oscillatory shear fluidized the CSK matrix, which was followed by slow scale-free recovery of rheological properties (aging). Spontaneous bead motions were subdiffusive at short times but superdiffusive at longer times; intermittent motions reflecting nanoscale CSK rearrangements depended on both the approach to kinetic arrest and energy release due to ATP hydrolysis. Aging, intermittency, and approach to kinetic arrest establish a striking analogy between the behaviour of the living CSK and that of inert non-equilibrium systems, including soft glasses, but with important differences that are highly ATP-dependent. These mesoscale dynamics link integrative CSK functions to underlying molecular events, and represent an important intersection of topical issues in condensed matter physics and systems biology.

Mission Design of LiteBIRD

Abstract: LiteBIRD is a next-generation satellite mission to measure the polarization of the cosmic microwave background (CMB) radiation. On large angular scales the B-mode polarization of the CMB carries the imprint of primordial gravitational waves, and its precise measurement would provide a powerful probe of the epoch of inflation. The goal of LiteBIRD is to achieve a measurement of the characterizing tensor to scalar ratio $$r$$ to an uncertainty of $$\delta r=0.001$$ . In order to achieve this goal we will employ a kilo-pixel superconducting detector array on a cryogenically cooled sub-Kelvin focal plane with an optical system at a temperature of 4 K. We are currently considering two detector array options; transition edge sensor (TES) bolometers and microwave kinetic inductance detectors. In this paper we give an overview of LiteBIRD and describe a TES-based polarimeter designed to achieve the target sensitivity of 2 $$\upmu $$ K arcmin over the frequency range 50–320 GHz.

Periodontal Ligament Cells Under Mechanical Stress Induce Osteoclastogenesis by Receptor Activator of Nuclear Factor κB Ligand Up-Regulation via Prostaglandin E2 Synthesis†

Abstract: Previously, we discovered that periodontal ligament (PDL) cells not only support osteoclastogenesis through cell-to-cell contact, but also inhibit the formation of tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cells by a producing soluble factor(s). Furthermore, PDL cells express both receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) messenger RNA (mRNA). Clinically, "ankylosed teeth," which lack periodontal ligament, cannot be moved with orthodontic tooth treatment. From this, we hypothesized that PDL cells under mechanical stress should play a pivotal role in osteoclast formation during orthodontic tooth movement. This study examined how mechanical stress affects the osteoclastogenesis-supporting activity of PDL cells. PDL cells were compressed continuously and then cocultured with peripheral blood mononuclear cells (PBMCs) for 4 weeks. PDL cells under mechanical stress up-regulated osteoclastogenesis from PBMCs. Furthermore, the expression of RANKL mRNA and protein in PDL cells increased with compressive force in parallel with the change in the number of osteoclasts. In addition, cyclo-oxygenase 2 (COX-2) mRNA expression was induced by compressive force, and indomethacin inhibited the RANKL up-regulation resulting from compressive force. PDL cells under compressive force exhibited significantly increased prostaglandin E2 (PGE2) production in comparison with control PDL cells. Exogenous PGE2 treatment increased RANKL mRNA expression in PDL cells. Interestingly, OPG expression remained constant throughout compressive force or PGE2 treatment. In conclusion, compressive force up-regulated RANKL expression in PDL cells. Furthermore, RANKL up-regulation in mechanically stressed PDL cells was dependent on PGE2.