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Megumi Sumizono,1,2 Yushin Yoshizato,1 Ryohei Yamamoto,1 Takaki Imai,1 Akira Tani,2 Kazuki Nakanishi,2 Tomomi Nakakogawa,2 Teruki Matsuoka,2 Ryoma Matsuzaki,2 Takashi Tanaka,3 Harutoshi Sakakima2 1Department of Rehabilitation, Kyushu University of Nursing and Social Welfare, Kumamoto, Japan; 2Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan; 3Department of Rehabilitation, Kumamoto Health Science University, Kumamoto, JapanCorrespondence: Megumi Sumizono, Department of Rehabilitation, Kyushu University of Nursing and Social Welfare, 888 Tominoo, Tamana, Kumamoto, 865-0062, Japan, Tel/Fax +81 968-75-1931, Email sumizono@kyushu-ns.ac.jpPurpose: Pain disrupts the daily and social lives of patients with neuropathic pain. Effective treatment of neuropathic pain is difficult. Pharmacological treatments for neuropathic pain are limited, and 40– 60% of patients do not achieve even partial relief of their pain. This study created a chronic constriction injury (CCI) model in rats to examine the effects of regular exercise on neuropathic pain relief, elucidate the mechanism, and determine the effects of neuropathic pain in the hippocampus.Methods: CCI model rats were randomly divided into exercise (Ex) and no exercise (No-Ex) groups. Normal rats (Normal group) were used as controls. The Ex group exercised on a treadmill at 20 m/min for 30 min, 5 days per week for 5 weeks post-CCI. The 50% pain response threshold was assessed by mechanical stimulation. Using immunohistochemistry, we examined activation of glial cells (microglia and astrocytes) by CCR2 and TRAF6 expression in the spinal cord dorsal horn and DCX and PROX1 expression in the hippocampal dentate gyrus.Results: The 50% pain response threshold was significantly lower in the Ex than in the No-Ex group at 5 weeks post-CCI, indicating pain relief. In the spinal cord dorsal horn, IBA1, CCR2, and TRAF6 expression was markedly lower in the Ex group than in the No-Ex group at 3 weeks post-CCI. IBA1, GFAP, CCR2, and TRAF6 expression was markedly lower in the Ex group than in the No-Ex group at 5 weeks post-CCI. In the hippocampus, DCX, but not PROX1, expression was significantly higher in the Ex group than in the No-Ex group at 3 weeks post-CCI. At 5 weeks post-CCI, both DCX and PROX1 expression was markedly increased in the Ex group compared to the No-Ex group.Conclusion: Our findings suggest that regular exercise can improve the neuropathic pain-induced neurogenic dysfunction in the hippocampal dentate gyrus.Keywords: CCR2, hippocampal dentate gyrus, microglia, neurogenesis, spinal dorsal horn, TRAF6

Megumi Sumizono,1,2 Harutoshi Sakakima,1 Shotaro Otsuka,1 Takuto Terashi,1 Kazuki Nakanishi,1,2 Koki Ueda,1,2 Seiya Takada,1,2 Kiyoshi Kikuchi3 1Course of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan; 2Kirishima Orthopedics, Kirishima, Japan; 3Division of Brain Science, Department of Physiology, Kurume University School of Medicine, Kurume, Japan Background: Exercise regimens are established methods that can relieve neuropathic pain. However, the relationship between frequency and intensity of exercise and multiple cellular responses of exercise-induced alleviation of neuropathic pain is still unclear. We examined the influence of exercise frequency on neuropathic pain and the intracellular responses in a sciatic nerve chronic constriction injury (CCI) model. Materials and methods: Rats were assigned to four groups as follows: CCI and high-frequency exercise (HFE group), CCI and low-frequency exercise (LFE group), CCI and no exercise (No-Ex group), and naive animals (control group). Rats ran on a treadmill, at a speed of 20 m/min, for 30 min, for 5 (HFE) or 3 (LFE) days a week, for a total of 5 weeks. The 50% withdrawal threshold was evaluated for mechanical sensitivity. The activation of glial cells (microglia and astrocytes), expression of brain-derived neurotrophic factor (BDNF) and μ-opioid receptor in the spinal dorsal horn and endogenous opioid in the midbrain were examined using immunohistochemistry. Opioid receptor antagonists (naloxone) were administered using intraperitoneal injection. Results: The development of neuropathic pain was related to the activation of glial cells, increased BDNF expression, and downregulation of the μ-opioid receptor in the ipsilateral spinal dorsal horn. In the No-Ex group, neuropathic pain showed the highest level of mechanical hypersensitivity at 2 weeks, which improved slightly until 5 weeks after CCI. In both exercise groups, the alleviation of neuropathic pain was accelerated through the regulation of glial activation, BDNF expression, and the endogenous opioid system. The expression of BDNF and endogenous opioid in relation to exercise-induced alleviation of neuropathic pain differed in the HFE and LFE groups. The effects of exercise-induced alleviation of mechanical hypersensitivity were reversed by the administration of naloxone. Conclusion: The LFE and HFE program reduced neuropathic pain. Our findings indicated that aerobic exercise-induced alleviated neuropathic pain through the regulation of glial cell activation, expression of BDNF in the ipsilateral spinal dorsal horn, and the endogenous opioid system. Keywords: exercise, neuropathic pain, rehabilitation, glial cells, endogenous opioid

The magnetic, structural and corrosive properties of sputtered FeSiA1(Ti/Ta)(O)N films were investigated. The films are believed to be sensitive on the grain structure due to the small magnetocrystalline anisotropy (K(sub1)) of the FeSiA1 system. Soft magnetic properties were observed following thermal treatment, and the composition of the granular grains and needle shaped grains were mostly Fe and FeSi.

This paper reports enhancement of magnetoresistance in spin-valve trilayers by improving specular reflectivity of conduction electrons at the film surface of the metal capping layer. The samples were epitaxially grown on MgO(100) by ultrahigh vacuum deposition. The MR ratio of the MgO/Pt(10nm)/Cu(5nm)/Ni-Fe(5nm)/Cu(2.8nm)/Co(5nm)/Cu(1.2nm) film increased from 3.9% to 5.4% by the addition of a 3nm-thick-Ag capping layer. The enhancement of MR ratio may he attributed to the increase of specular reflection of conduction electrons at the Ag surface. Co layer thickness dependence of the MR ratio in the spin-valves also supports this interpretation.

In-plane magnetic anisotropy and thickness dependence of soft magnetic properties for Fe-Ta-N films near the eutectic composition, annealed either in a rotating magnetic field, in a static field or with no magnetic field were investigated in detail. The soft magnetic films were prepared by r.f. reactive sputtering. The films with thicknesses greater than around 2 micrometer have good soft magnetic properties. For those with thicknesses less than around 1 micrometer, the soft magnetic properties deteriorate and the domain structure changes with decreasing thickness. The films annealed without magnetic field or in a rotating field have an isotropic high permeability (mu-prime greater than or equal to 5000 at 1 MHz) and a low anisotropy field (H(sub k) approximately equal to 50 A/m), whereas for the films annealed in a static field, uniaxial anisotropy is induced. This anisotropy increases with increasing N concentration. Moreover, B was added to Fe-Ta-N system, and the relation between the structures and soft magnetic properties of Fe-Ta-B-N films was investigated. By adding B to Fe-Ta-N system, the thermal stability of soft magnetic properties is improved, because the growth of alpha-Fe and Ta-(N, B) grains is suppressed during annealing at higher temperatures.

PtMn based Spin-valves with or without specular reflective thin oxide layers, OL, were prepared by sputtering. The MR ratios and [Delta] Rs of the spin-valves without OL were about 8 % and 1.2 [Omega]. The values were increased up to 12-15% and [contains or equal to] 2.6 [Omega] by inserting an OL into the pinned and free layers. PtMn based spin-valves with synthetic AF and OL as the pinning layers were also studied. The MR ratio and [Delta] Rs were about 11% and 2.9 [Omega]. These PtMn based spin-valves showed better thermal stability than IrMn based spin-valves. Index Terms--GMR, spin-valves, specular scattering.

A new type of spin-valves using perovskite antiferromagnets, MFe[O.sub.3] (M=Y, La, Pr, Nd, Sm), as the pinning layers was developed. These spin-valves are composed of MFe[O.sub.3]/P/Cu/F, where P and F are the pinned and free layers, respectively, and were prepared by sputtering on Si or glass substrates. Among these spin-valves, LaFe[O.sub.3]/CoFe/Cu/CoFe showed large MR ratios, 11.4%, at R.T. and the MR ratios were stable even after the annealing at 350 [degrees] C. Index Terms--GMR, Spin-valves, Perovskite, LaFe[O.sub.3],

Presents a study that examined the magnetic properties of compositionally modulated films (CMF) which are composed of cobalt and manganese layers. Typical experimental parameters for CMF; Diffraction patterns of the CMF; Parts of the CMF; Potential reasons for the decreased magnetization of the CMF.