Periodic orbit resonances in layered metals in tilted magnetic fields

The frequency dependence of the interlayer conductivity of a layered Fermi liquid in a magnetic field which is tilted away from the normal to the layers is considered. For both quasi-one- and quasi-two-dimensional systems resonances occur when the frequency is a harmonic of the frequency at which the magnetic field causes the electrons to oscillate on the Fermi surface within the layers. The intensity of the different harmonic resonances varies significantly with the direction of the field. The resonances occur for both coherent and weakly incoherent interlayer transport and so their observation does not imply the existence of a three-dimensional Fermi surface.Comment: 4 pages, RevTeX + epsf, 2 figures. Discussion of other work revised. To appear in Phys. Rev. B, Rapid Commun., October 1

Fermi Surface Study of Quasi-Two-Dimensional Organic Conductors by Magnetooptical Measurements

Magnetooptical measurements of several quasi-two-dimensional (q2D) organic conductors, which have simple Fermi surface structure, have been performed by using a cavity perturbation technique. Despite of the simple Fermi surface structure, magnetooptical resonance results show a dramatic difference for each sample. Cyclotron resonances (CR) were observed for q-(BEDT-TTF)2I3 and (BEDT-TTF)3Br(pBIB), while periodic orbit resonances (POR) were observed for (BEDT-TTF)2Br(DIA) and (BEDT-TTF)3Cl(DFBIB). The selection of the resonance seems to correspond with the skin depth for each sample. The effective mass of POR seems to have a mass enhancement due to the many-body effect, while effective mass of CR is independent of the strength of the electron-electron interaction. The scattering time deduced from each resonance's linewidth will be also presented.Comment: 10 pages, 8 figures, to be published to J. Phys. Soc. Jpn Vol.72 No.1 (accepted

MICROSTRUCTURE OF CAST Pr-Fe-B MAGNETS

CAST Pr-Fe-B-Cu magnets, which were hot-pressed so as to yield magnetic alignment, are found to be composed primarily of a Pr2Fe14B and also show traces of a Pr-rich phase. The magnetic Pr2Fe14B phase is concentrated by discharging the Pr-rich phase during hot-pressing. It is found Cu exists mainly in the Pr-rich phase and lowers the melting point of it. The lowered melting point greatly improves the ability of plastic deformation

Expression of protease activating receptor-2 (PAR-2) is positively correlated with the recurrence of non-muscle invasive bladder cancer: an immunohistochemical analysis

Kozue Nakahara,1 Koji Yamasaki,1 Takahiro Nagai,1 Masato Fujii,1 Takahiro Akioka,1 Hiroki Takamori,1 Naoki Terada,1 Shoichiro Mukai,1 Yuichiro Sato,2 Toshiyuki Kamoto11Department of Urology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 2Section of Diagnostic Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, JapanBackground: Matriptase, which is a Type II transmembrane serine protease, has the potential to activate several growth factors, including pro-hepatocyte growth factor (HGF). A G protein-coupled transmembrane cell-surface receptor and a protease-activated receptor 2 (PAR-2) are also required for activation by matriptase. Activation of PAR-2 has been reported to induce the progression of various cancers. In a previous study, we evaluated the correlation between upregulation of MET phosphorylation with high matriptase expression and worse prognosis in patients with muscle invasive bladder cancer; however, expression of PAR-2, matriptase and MET in non-muscle invasive bladder cancer (NMIBC) has not been evaluated.Materials and methods: We retrospectively analyzed the expression of PAR-2, matriptase and MET using 55 paraffin-embedded specimens obtained from patients with NMIBC by immunohistochemistry.Results: MET was significantly expressed in high-grade urothelial carcinoma (UC) and pathological T1 cancers. High expression of PAR-2 was significantly associated with a worse recurrence rate in NMIBC. In subgroup analysis, the expression of PAR-2 was also correlated with high recurrence rate in low-grade UC. In addition, expression of matriptase tended to correlate with worse recurrence rate in high-grade UC.Conclusion: Increased expression of PAR-2 was significantly correlated with worse recurrence rate in patients with NMIBC. In addition, expression of matriptase also indicated a tendency toward recurrence in high-grade UC, suggesting an important role of matriptase-induced PAR-2 activation in NMIBC.Keywords: PAR-2, matriptase, MET, NMIB

Effects of eplerenone on transcriptional factors and mRNA expression related to cardiac remodelling after myocardial infarction

Objective: To examine the effects of eplerenone, a selective aldosterone blocker, on cardiac function after myocardial infarction (MI) and myocardial remodelling related transcriptional factors and mRNA expression in non-infarcted myocardium. Methods: MI was induced by ligation of the coronary artery in Wistar rats. Rats were randomly assigned to a vehicle treated group or an eplerenone treated group (100 mg/kg/day). Results: At four weeks after MI, left ventricular (LV) end diastolic pressure, LV weight, and LV end diastolic dimension were increased in MI rats. Eplerenone significantly reduced the increase in LV end diastolic pressure, LV weight, and LV end diastolic dimension. In the MI rats the decreased ejection fraction indicated systolic dysfunction and the increased E wave to A wave ratio and E deceleration rate indicated diastolic dysfunction. Eplerenone significantly attenuated this systolic and diastolic dysfunction. Myocardial interstitial fibrosis, transcriptional activities of activator protein 1 and nuclear factor κB, and mRNA expression of monocyte chemoattractant protein 1, plasminogen activator inhibitor 1, atrial natriuretic peptide, brain natriuretic peptide, and collagen types I and III were significantly increased at four weeks after MI. Eplerenone significantly attenuated interstitial fibrosis and suppressed transcriptional activity and mRNA expression of these genes. Conclusions: When administered after MI, eplerenone prevents cardiac remodelling accompanied by systolic and diastolic dysfunction and inhibits abnormal myocardial transcriptional activities and gene expression