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Kitano Y, Wakimoto S, Tamura S, Kubota K, Domon Y, Arakawa N, Saito M, Sava B, Buisson B. Effects of mirogabalin, a novel ligand for the α₂δ subunit of voltage-gated calcium channels, on N-type calcium channel currents of rat dorsal root ganglion culture neurons. Pharmazie 2019; 74:147-149. [PMID: 30961679 DOI: 10.1691/ph.2019.8833] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
Mirogabalin, which is a novel ligand for the α₂δ subunit of voltage-gated calcium channels, is being developed for treating neuropathic pain including diabetic peripheral neuropathy and postherpetic neuralgia. Mirogabalin possesses unique α₂δ subunit binding characteristics and has potent and long-lasting analgesic effects in neuropathic pain models. In the present study, we investigated the effects of mirogabalin on N-type calcium channel currents of the rat dorsal root ganglion (DRG) culture neurons using the whole-cell patch clamp technique. Small or medium DRG neurons were isolated from Sprague-Dawley rats and were incubated for 20 to 24 h with mirogabalin or pregabalin. The DRG neurons were depolarised from a holding potential of -40 mV to +40 mV in steps of 10 mV for 220 ms, and elicited N-type calcium channel currents were recorded. The N-type calcium channel currents were verified by sensitivity to ω-conotoxin GVIA, a selective N-type calcium channel blocker. Mirogabalin inhibited the calcium channel currents of rat DRG neurons at 50 μM, and pregabalin inhibited them at 200 μM. Mirogabalin and pregabalin showed significant differences in the peak current densities at depolarisation to -20 and -10 mV when compared with that shown by the vehicle control. In conclusion, mirogabalin inhibits N-type calcium channel currents in rat DRG culture neurons. The potent and long-lasting analgesic effects of mirogabalin are thought to be associated with its potent and selective binding to α₂δ-1 subunits and following functional inhibition of calcium channel currents.
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Lin JQ, Liu X, Blackburn E, Wakimoto S, Ding H, Islam Z, Sinha SK. Quantitative Characterization of the Nanoscale Local Lattice Strain Induced by Sr Dopants in La_{1.92}Sr_{0.08}CuO_{4}. Phys Rev Lett 2018; 120:197001. [PMID: 29799254 DOI: 10.1103/physrevlett.120.197001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 01/24/2018] [Indexed: 06/08/2023]
Abstract
The nanometer scale lattice deformation brought about by the dopants in the high temperature superconducting cuprate La_{2-x}Sr_{x}CuO_{4} (x=0.08) was investigated by measuring the associated x-ray diffuse scattering around multiple Bragg peaks. A characteristic diffuse scattering pattern was observed, which can be well described by continuum elastic theory. With the fitted dipole force parameters, the acoustic-type lattice deformation pattern was reconstructed and found to be of similar size to lattice thermal vibration at 7 K. Our results address the long-term concern of dopant introduced local lattice inhomogeneity, and show that the associated nanometer scale lattice deformation is marginal and cannot, alone, be responsible for the patched variation in the spectral gaps observed with scanning tunneling microscopy in the cuprates.
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Affiliation(s)
- J Q Lin
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - X Liu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - E Blackburn
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - S Wakimoto
- Materials Sciences Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - H Ding
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - Z Islam
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - S K Sinha
- Department of Physics, University of California, San Diego, La Jolla, California 92093, USA
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Sakurai Y, Itou M, Barbiellini B, Mijnarends PE, Markiewicz RS, Kaprzyk S, Gillet JM, Wakimoto S, Fujita M, Basak S, Wang YJ, Al-Sawai W, Lin H, Bansil A, Yamada K. Imaging Doped Holes in a Cuprate Superconductor with High-Resolution Compton Scattering. Science 2011; 332:698-702. [DOI: 10.1126/science.1199391] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Kanazawa N, Onose Y, Arima T, Okuyama D, Ohoyama K, Wakimoto S, Kakurai K, Ishiwata S, Tokura Y. Large topological Hall effect in a short-period helimagnet MnGe. Phys Rev Lett 2011; 106:156603. [PMID: 21568591 DOI: 10.1103/physrevlett.106.156603] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Indexed: 05/30/2023]
Abstract
We have observed an unconventional, likely topological, Hall effect over a wide temperature region in the magnetization process of a chiral-lattice helimagnet MnGe. The magnitude of the topological Hall resistivity is nearly temperature-independent below 70 K, which reflects the real-space fictitious magnetic field proportional to a geometric quantity (scalar spin chirality) of the underlying spin texture. From the neutron diffraction study, it is anticipated that a relatively short-period (3-6 nm) noncoplanar spin structure is stabilized from the proper screw state in a magnetic field to produce the largest topological Hall response among the B20-type (FeSi-type) chiral magnets.
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Affiliation(s)
- N Kanazawa
- Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo 113-8656, Japan
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Tokunaga Y, Kaneko Y, Okuyama D, Ishiwata S, Arima T, Wakimoto S, Kakurai K, Taguchi Y, Tokura Y. Multiferroic M-type hexaferrites with a room-temperature conical state and magnetically controllable spin helicity. Phys Rev Lett 2010; 105:257201. [PMID: 21231619 DOI: 10.1103/physrevlett.105.257201] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Indexed: 05/30/2023]
Abstract
Magnetic and magnetoelectric (ME) properties have been studied for single crystals of Sc-doped M-type barium hexaferrites. Magnetization (M) and neutron diffraction measurements revealed that by tuning Sc concentration a longitudinal conical state is stabilized up to above room temperatures. ME measurements have shown that a transverse magnetic field (H) can induce electric polarization (P) at lower temperatures and that the spin helicity is nonvolatile and endurable up to near the conical magnetic transition temperature. It was also revealed that the response (reversal or retention) of the P vector upon the reversal of M varies with temperature. In turn, this feature allows us to control the relation between the spin helicity and the M vectors with H and temperature.
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Affiliation(s)
- Y Tokunaga
- Multiferroics Project, ERATO, Japan Science and Technology Agency (JST), Wako, Saitama 351-0198, Japan
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Fukunaga M, Sakamoto Y, Kimura H, Noda Y, Abe N, Taniguchi K, Arima T, Wakimoto S, Takeda M, Kakurai K, Kohn K. Magnetic-field-induced polarization flop in multiferroic TmMn2O5. Phys Rev Lett 2009; 103:077204. [PMID: 19792682 DOI: 10.1103/physrevlett.103.077204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Indexed: 05/28/2023]
Abstract
We discovered a reversible electric polarization flop from the a axis (P(a)) to the b axis (P(b)) in multiferroic TmMn2O5 below 5 K by applying a magnetic field of approximately 0.5 T along the c axis. This phenomenon is the first example of the rare-earth (R) compound RMn2O5. This magnetic-field-induced polarization flop corresponds to a magnetic phase transition from one incommensurate magnetic (ICM) P(a) phase to another ICM P(b) phase, which is equivalent to an ICM P(b) phase above 5 K under no magnetic field. The spin chirality in the bc plane, which was observed in the P(b) phase by polarized neutron diffraction, disappeared in the ICM P(a) phase. This indicates that the polarization in the ICM phases of TmMn2O5 was induced by an S(i) x S(j)-type interaction.
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Affiliation(s)
- M Fukunaga
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan.
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Wakimoto S, Kimura H, Ishii K, Ikeuchi K, Adachi T, Fujita M, Kakurai K, Koike Y, Mizuki J, Noda Y, Yamada K, Said AH, Shvyd'ko Y. Charge excitations in the stripe-ordered La5/3Sr1/3NiO4 and La2-x(Ba,Sr)xCuO4 superconducting compounds. Phys Rev Lett 2009; 102:157001. [PMID: 19518667 DOI: 10.1103/physrevlett.102.157001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Indexed: 05/27/2023]
Abstract
Charge excitations in stripe-ordered 214 compounds La_{5/3}Sr_{1/3}NiO_{4} and 1/8-doped La2-x(Ba or Sr)xCuO4 are studied using resonant inelastic x-ray scattering in the hard x-ray regime. We observe = or approximately 1 eV excitation with a momentum transfer corresponding to the charge stripe spatial period both for the diagonal (nickelate) and parallel (cuprates) stripes. They are interpreted as collective stripe excitations or anomalous softening of the charge excitonic modes of the in-gap states.
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Affiliation(s)
- S Wakimoto
- Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
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Matsuda M, Fujita M, Wakimoto S, Fernandez-Baca JA, Tranquada JM, Yamada K. Magnetic dispersion of the diagonal incommensurate phase in lightly doped La2-xSrxCuO4. Phys Rev Lett 2008; 101:197001. [PMID: 19113297 DOI: 10.1103/physrevlett.101.197001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Indexed: 05/27/2023]
Abstract
We present inelastic neutron scattering experiments on a single-domain crystal of lightly doped La1.96Sr0.04CuO4. We find that the magnetic excitation spectrum in this insulating phase with a diagonal incommensurate spin modulation is remarkably similar to that in the superconducting regime, where the spin modulation is bond parallel. In particular, we find that the dispersion slope at low energy is essentially independent of doping and temperature over a significant range. The energy at which the excitations cross the commensurate antiferromagnetic wave vector increases roughly linearly with doping through the underdoped regime.
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Affiliation(s)
- M Matsuda
- Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
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MacDougall GJ, Aczel AA, Carlo JP, Ito T, Rodriguez J, Russo PL, Uemura YJ, Wakimoto S, Luke GM. Absence of broken time-reversal symmetry in the pseudogap state of the high temperature La(2-x)SrxCuO4 superconductor from muon-spin-relaxation measurements. Phys Rev Lett 2008; 101:017001. [PMID: 18764143 DOI: 10.1103/physrevlett.101.017001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Indexed: 05/26/2023]
Abstract
We have performed zero-field muon-spin-relaxation measurements on single crystals of La(2-x)SrxCuO4 to search for spontaneous currents in the pseudogap state. By comparing measurements on materials across the phase diagram, we put strict upper limits on any possible time-reversal symmetry breaking fields that could be associated with the pseudogap. Comparison between experimental limits and the proposed circulating current states effectively eliminates the possibility that such states exist in this family of materials.
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Affiliation(s)
- G J MacDougall
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada, L8S-4M1
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Hill JP, Blumberg G, Kim YJ, Ellis DS, Wakimoto S, Birgeneau RJ, Komiya S, Ando Y, Liang B, Greene RL, Casa D, Gog T. Observation of a 500 meV collective mode in La2-xSrxCuO4 and Nd2CuO4 using resonant inelastic X-ray scattering. Phys Rev Lett 2008; 100:097001. [PMID: 18352743 DOI: 10.1103/physrevlett.100.097001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Indexed: 05/26/2023]
Abstract
Utilizing resonant inelastic x-ray scattering, we report a previously unobserved mode in the excitation spectrum of La2-xSrxCuO4 and Nd2CuO4 at 500 meV. The mode is peaked around the (pi, 0) point in reciprocal space and is observed to soften, and broaden, away from this point. Samples with x=0, 0.01, 0.05, and 0.17 were studied. The new mode is found to be rapidly suppressed with increasing Sr content and is absent at x=0.17, where it is replaced by a continuum of excitations. This mode is only observed when the incident x-ray polarization is normal to the CuO planes.
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Affiliation(s)
- J P Hill
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
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11
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Wakimoto S, Yamada K, Tranquada JM, Frost CD, Birgeneau RJ, Zhang H. Disappearance of antiferromagnetic spin excitations in overdoped La2-xSrxCuO4. Phys Rev Lett 2007; 98:247003. [PMID: 17677985 DOI: 10.1103/physrevlett.98.247003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Indexed: 05/16/2023]
Abstract
Magnetic excitations for energies up to approximately 100 meV are studied for overdoped La(2-x)Sr(x)CuO(4) with x=0.25 and 0.30, using time-of-flight neutron spectroscopy. Comparison of spectra integrated over the width of an antiferromagnetic Brillouin zone demonstrates that the magnetic scattering at intermediate energies, 20 <or= omega <or= 100 meV, progressively decreases with overdoping. This strongly suggests that the magnetism is not related to Fermi surface nesting, but rather is associated with a decreasing volume fraction of (probably fluctuating) antiferromagnetic bubbles.
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Affiliation(s)
- S Wakimoto
- Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
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Nakajima K, Nakamura M, Kajimoto R, Osakabe T, Kakurai K, Matsuda M, Metoki M, Wakimoto S, Sato TJ, Itoh S, Arai M, Yoshida K, Niita K. Cold-neutron disk-chopper spectrometer at J-PARC. J of Neutron Res 2007. [DOI: 10.1080/10238160601045722] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wakimoto S, Zhang H, Yamada K, Swainson I, Kim H, Birgeneau RJ. Direct relation between the low-energy spin excitations and superconductivity of overdoped high-Tc superconductors. Phys Rev Lett 2004; 92:217004. [PMID: 15245312 DOI: 10.1103/physrevlett.92.217004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2003] [Indexed: 05/24/2023]
Abstract
The dynamic spin susceptibility, chi(")(omega), has been measured over the energy range of 2</=omega</=10 meV for overdoped La2-xSrxCuO4. Incommensurate (IC) spin excitations are observed at 8 K for all superconducting samples for 0.25</=x</=0.28 with chi(") peaking at approximately 6 meV. The IC peaks at 6 meV become smaller in intensity with increasing x and, finally, become unobservable for a sample with x=0.30 which has no bulk superconductivity. The maximum chi(") decreases linearly with T(c)(onset) in the overdoped region, implying a direct cooperative relation between the spin fluctuations and the superconductivity.
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Affiliation(s)
- S Wakimoto
- Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada
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Hawthorn DG, Hill RW, Proust C, Ronning F, Sutherland M, Boaknin E, Lupien C, Tanatar MA, Paglione J, Wakimoto S, Zhang H, Taillefer L, Kimura T, Nohara M, Takagi H, Hussey NE. Field-induced thermal metal-to-insulator transition in underdoped La(2-x)Sr(x)CuO(4+delta). Phys Rev Lett 2003; 90:197004. [PMID: 12785975 DOI: 10.1103/physrevlett.90.197004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2002] [Indexed: 05/24/2023]
Abstract
The transport of heat and charge in cuprates was measured in single crystals of La(2-x)Sr(x)CuO(4+delta) (LSCO) across the doping phase diagram at low temperatures. In underdoped LSCO, the thermal conductivity is found to decrease with increasing magnetic field in the T-->0 limit, in striking contrast to the increase observed in all superconductors, including cuprates at higher doping. In heavily underdoped LSCO, where superconductivity can be entirely suppressed with an applied magnetic field, we show that a novel thermal metal-to-insulator transition takes place upon going from the superconducting state to the field-induced normal state.
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Affiliation(s)
- D G Hawthorn
- Department of Physics, University of Toronto, Toronto, Ontario, Canada
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Kim YJ, Hill JP, Burns CA, Wakimoto S, Birgeneau RJ, Casa D, Gog T, Venkataraman CT. Resonant inelastic x-ray scattering study of charge excitations in La(2)CuO(4). Phys Rev Lett 2002; 89:177003. [PMID: 12398699 DOI: 10.1103/physrevlett.89.177003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2002] [Indexed: 05/24/2023]
Abstract
We report a resonant inelastic x-ray scattering study of the dispersion relations of charge-transfer excitations in insulating La(2)CuO(4).. These data reveal two peaks, both of which show two-dimensional characteristics. The lowest energy excitation has a gap energy of approximately 2.2 eV at the zone enter, and a dispersion of approximately 1 eV. The spectral weight of this mode becomes dramatically smaller around (pi, pi). The second peak shows a smaller dispersion ( approximately 0.5 eV) with a zone-center energy of approximately 3.9 eV. We argue that these are both highly dispersive exciton modes damped by the presence of the electron-hole continuum.
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Affiliation(s)
- Y J Kim
- Department of Physics, Brookhaven National Laboratory, Upton, New York 11973, USA
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Ishimi Y, Yoshida M, Wakimoto S, Wu J, Chiba H, Wang X, Takeda K, Miyaura C. Genistein, a soybean isoflavone, affects bone marrow lymphopoiesis and prevents bone loss in castrated male mice. Bone 2002; 31:180-5. [PMID: 12110432 DOI: 10.1016/s8756-3282(02)00780-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Soybean isoflavones exhibit selective effects on bone metabolism in postmenopausal women as well as in ovariectomized animals. Recently, the role of estrogen in bone metabolism in men has also received attention, because a man with a mutated estrogen receptor-alpha (ER(alpha)) gene will exhibit osteoporotic phenotypes. To examine the possible role of genistein, a soybean isoflavone, in bone marrow hemopoiesis and bone metabolism in men, male mice were orchidectomized (orx) and treated with genistein (0.4-0.8 mg/day) or 17beta-estradiol (E(2); 0.03 microg/day) subcutaneously for 3 weeks. In orx mice, seminal vesicle weight decreased markedly, and it was not affected by the administration of genistein or E(2). The number of bone marrow cells was markedly increased after orx, and the majority was B-220 weakly positive pre-B cells. Increased B-lymphopoiesis was restored completely by E(2) or genistein administration. In orx mice, bone mineral density of the femur decreased markedly, and this bone loss was prevented to a significant extent by treatment with genistein as well as E(2). Histomorphometry showed that the trabecular bone volume in the femoral distal metaphysis decreased markedly after orx, and genistein and E(2) prevented this bone loss. These results suggest that soybean isoflavones prevent bone loss due to androgen deficiency in males.
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Affiliation(s)
- Y Ishimi
- Division of Food Science, National Institute of Health and Nutrition, Tokyo, Japan.
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Gehring PM, Wakimoto S, Ye ZG, Shirane G. Soft mode dynamics above and below the Burns temperature in the relaxor Pb(Mg1/3Nb2/3)O3. Phys Rev Lett 2001; 87:277601. [PMID: 11800914 DOI: 10.1103/physrevlett.87.277601] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2001] [Indexed: 05/23/2023]
Abstract
We report neutron inelastic scattering measurements of the lowest-energy transverse optic (TO) phonon branch in the relaxor Pb(Mg1/3Nb2/3)O3 from 400 to 1100 K. Far above the Burns temperature T(d) approximately 620 K we observe well-defined propagating TO modes at all wave vectors q, and a zone center TO mode that softens in a manner consistent with that of a ferroelectric soft mode. Below T(d) the zone center TO mode is overdamped. This damping extends up to, but not above, the waterfall wave vector q(wf), which is a measure of the average size of the polar nanoregions.
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Affiliation(s)
- P M Gehring
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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Abstract
Optical conductivity measurements on the perovskite-related oxide CaCu3Ti4O12 provide a hint of the physics underlying the observed giant dielectric effect in this material. A low-frequency vibration displays anomalous behavior, implying that there is a redistribution of charge within the unit cell at low temperature. At infrared frequencies (terahertz), the value for the dielectric constant is approximately 80 at room temperature, which is far smaller than the value of approximately 10(5) obtained at lower radio frequencies (kilohertz). This discrepancy implies the presence of a strong absorption at very low frequencies due to dipole relaxation. At room temperature, the characteristic relaxation times are fast (less than or approximately 500 nanoseconds) but increase dramatically at low temperature, suggesting that the large change in dielectric constant may be due to a relaxor-like dynamical slowing down of dipolar fluctuations in nanosize domains.
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Affiliation(s)
- C C Homes
- Department of Physics, Building 510B, Brookhaven National Laboratory, Upton, NY 11973-5000, USA.
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Yamada K, Wakimoto S, Shirane G, Lee CH, Kastner MA, Hosoya S, Greven M, Endoh Y, Birgeneau RJ. Direct Observation of a Magnetic Gap in Superconducting La1.85Sr0.15CuO4 (Tc=37.3K). Phys Rev Lett 1995; 75:1626-1629. [PMID: 10060345 DOI: 10.1103/physrevlett.75.1626] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Matsumoto M, Shoyama Y, Nishioka I, Iwai H, Wakimoto S. Identification of viruses infected in Rehmannia glutinosa Libosch. var purpurea Makino and effect of virus infection on root yield and iridoid glycoside contents. Plant Cell Rep 1989; 7:636-638. [PMID: 24240449 DOI: 10.1007/bf00272048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/1988] [Revised: 12/27/1988] [Indexed: 06/02/2023]
Abstract
Virus free plants of Rehmannia glutinosa Libosch. var. purpurea Makino were obtained through meristem tip tissue cultures from plants infected with a mixture of tabocco mosaic virus(TMV), a member of the carlavirus group, and an unknown spherical virus. The re-infection rate of the virus free plants by TMV in the field was determined by enzyme linked immunosorbent assay(ELISA). Twenty seven percent of the plants were re-infected during the first year, 31 % by the end of second year, and 63 % by the end of the third year. The yield of root and iridoid glycoside contents gradually decreased each year. These results led to the conclusion that virus infection causes marked decrease of the yield of roots and productivity of secondary metabolites.
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Affiliation(s)
- M Matsumoto
- Faculty of Pharmaceutical Sciences, Kyushu University, Higashi-ku, 812, Fukuoka, Japan
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Tadagaki H, Shigeta S, Ota F, Kanto Y, Wakimoto S. [Activities of an organization for promotion of maternal and child health at Okayama City: organized activities for health promotion]. Hokenfu Zasshi 1985; 41:503-23. [PMID: 3851034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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22
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Hirabayashi K, Wakimoto S, Inoue K, Ishikawa H. [Significance of preoperative irradiation using comparatively low doses in cervical cancer]. Nihon Sanka Fujinka Gakkai Zasshi 1971; 23:1089-94. [PMID: 5169280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Wakimoto S. [Study of preoperative irradiation in cervical cancer of the uterus]. Nihon Sanka Fujinka Gakkai Zasshi 1967; 19:563-72. [PMID: 5625143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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