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The structural changes and superconductivity in the layered non-stoichiometric niobium diboride compound were systematically studied for both of niobium-deficient and boron-deficient phases by X-ray diffraction analysis and magnetic susceptibility measurements. The niobium and boron vacancies were found to have different effects on the crystal lattice parameters and superconducting properties; superconductivity only exists in niobium-deficient phases with a clear enhancement of inner-plane B–B bonding and the increase of inter-plane distance, while boron vacancies have the opposite effect of enhancing the Nb–B bonding and breaking the superconductivity. A main superconducting phase with Nb0.83B2 composition was obtained with Tc ∼ 9.3–9.9 K, and a = 3.102(1) A and c = 3.322(2) A under the optimum sintering conditions. The low temperature specific heat was measured for three high-pressure synthesized superconducting samples to reveal the origin the increase of Tc with the niobium deficiencies.

The small angle neutron scattering diffraction patterns from the flux line lattice state in the layered hexagonal superconductor CaAlSi are observed. Under an applied magnetic field (H) parallel to the crystalline c-axis, a hexagonal vortex structure is observed over the entire temperature/field regions. On the other hand, the vortex configuration under H∥a shows an ellipsoidal arrangement of the first-order Bragg peaks due to the anisotropic penetration depth. It was inferred from these results that the vortex state characterized by penetration depth and coherence length in CaAlSi may be described by that of anisotropic uniaxial superconductor using London theory.

We have succeeded in synthesizing a new member of ternary silicide NaAlSi with a superconducting transition temperature T c−onset = 7 K by high pressure technique. The crystal structure of NaAlSi is the layered diamond-like structure with a space group of P 4/ nmm (no. 129, Z = 3) and without inversion symmetry. The superconducting properties in NaAlSi have been investigated by means of DC and AC magnetic susceptibility measurements. These magnetic responses indicate that NaAlSi belongs to a conventional type-II superconductor with a Ginzbrug–Landau parameter κ = 13.8. From the band structure calculations, we found that the hole band of Si p- and electron Al s-orbitals play an important role for the superconductivity in this system.

The vortex state defined by two characteristic length scales, magnetic penetration depth ( λ ) and coherence length ( ξ ) , in a layered hexagonal superconductor CaAlSi was probed using muon spin rotation. From preliminary analysis using modified London model, we found that the in-plane λ increases with increasing magnetic field while inter-plane λ is almost independent of magnetic field. The presence of field-induced quasiparticle excitation manifested in the field dependence of λ suggests that CaAlSi has an anisotropic gap structure (nodes/dips or multi-gapped).

We have performed high-resolution angle-resolved photoemission spectroscopy on layered polymorph series of $1H\ensuremath{-}, 5H\ensuremath{-}$, and $6H\ensuremath{-}\mathrm{CaAlSi}$, which exhibit superconductivity below 6.5, 5.7, and 7.7 K, respectively. While the overall band structure in the valence-band region is similar among these compounds, the volume of the Fermi surface at the $M$ point and the magnitude of the superconducting gap are markedly different from each other. Implications of such variation in the electronic structure due to the superstructure along the $c$ axis are discussed in relation to the physical properties of CaAlSi.

Magnetic field dependence of the effective penetration depth ( λ ) determined by μ SR is reported for 1H- Ca ( Al 0.5 Si 0.5 ) 2 , a structurally new phase of Ca ( Al 0.5 Si 0.5 ) 2 . The new phase has an AlB 2 -type crystal structure with P3 symmetry which, in contrast to earlier reports, does not exhibit superlattice structure along the c-axis. The bulk susceptibility measurement indicates that the upper critical field is much lower than that in superstructured ones for both c- and a-axis directions. A weak anisotropy in the superconducting order parameter is suggested from the increase of λ with increasing external field.

A comprehensive magnetic and superconducting phase diagram determined by muon spin rotation/relaxation ( μ SR ) is presented for Ca 2 - x Na x CuO 2 Br 2 which has apical bromine atoms. Evidence for antiferromagnetic (AF) order in lightly doped samples and that for quasi-static spin glass (SG)-like state in moderately doped ones are obtained by ZF- μ SR at low temperatures. While the phase diagram is qualitatively similar to that in typical 2-1-4 cuprates including Ca 2 - x Na x CuO 2 Cl 2 and La 2 - x Sr x CuO 4 , it exhibits a slight shift (expansion) over the x axis.

The temperature dependence of muon spin relaxation rate exhibits a significant increase below ∼130 K in CaB6 and ∼110 K in BaB6, while no sigh of spontaneous muon precession signal under a zero field is observed. Moreover, the electric field gradient at the boron site measured by muon level-crossing resonance (μLCR) exhibits a step like change at ∼110 K in CaB6. These results suggest a change in electronic state and the associated emergence of weak random magnetism below 110–130 K in these alkaline earth hexaborides.

The temperature ($T$) and magnetic field ($H$) dependence of the magnetic penetration depth, $\lambda(T,H)$, in Ca(Al$_{0.5}$Si$_{0.5}$)$_2$ exhibits significant deviation from that expected for conventional BCS superconductors. In particular, it is inferred from a field dependence of $\lambda(H)$ ($\propto H$) at 2.0 K that the quasiparticle excitation is strongly enhanced by the Doppler shift. This suggests that the superconducting order parameter in Ca(Al$_{0.5}$Si$_{0.5}$)$_2$ is characterized by a small energy scale $\Delta_S/k_B\le 2$ K originating either from anisotropy or multi-gap structure.

The presence of spin–orbit (SO) interaction in a noncentrosymmetric superconductor, La 2 C 3 ( T c ≃ 11 K ) is demonstrated by muon spin rotation ( μ SR) in its normal state, where μ SR spectra exhibit field-induced weak depolarization due to van Vleck-like local susceptibility. In the mixed state, muon spin relaxation due to inhomogeneity of internal field ( σ v ) exhibits a field dependence that is characterized by a kink, where σ v (and hence the superfluid density) is more strongly reduced at lower fields. This is perfectly in line with the presence of a secondary energy gap previously inferred from the temperature dependence of σ v , and also consistent with the possible influence of asymmetric deformation of the Fermi surface due to the SO interaction.

SUMMARY This paper is concerned with a twenty-five year campaign against the relocation of the Komatsu-Tenmangu shrine as a result of the enlargement of the Kakehashi river. The Komatsu-Tenmangu shrine is an important cultural property of Japan, and was constructed by Toshitsune Maeda, the third dynasty of the Kaga clan in 1657. It is suggested that the primary reason why it took so long to settle this issue is a flaw in our social system for managing public works. It is concluded that preservation of cultural property is not always contrary to land development, and that the proposed procedures or something like them must be put into practice for the real expansion of our culture.

Lattice-dynamical properties of CaAlSi and SrAlSi with a similar layer structure to ${\text{MgB}}_{2}$ have been first investigated by both Raman-scattering and ab initio calculations. All Raman-active phonons with ${E}^{\ensuremath{'}}$ symmetry have been clearly observed for both compounds. Their line shapes are asymmetric but their linewidths are $\ensuremath{\sim}10\text{ }{\text{cm}}^{\ensuremath{-}1}$, which is very narrower than that of ${\text{MgB}}_{2}$. In addition to the Raman-active modes, several extra peaks have been observed below $160\text{ }{\text{cm}}^{\ensuremath{-}1}$. These low-energy extra modes can be assigned to the out-of-plane vibrations of Al perpendicular to Al-Si basal plane. Since these peak intensities are strongly affected by the incident energy (resonance Raman process), the electronic state is important for them. Moreover, in both crystals of CaAlSi and SrAlSi, we point out the energy difference for the different propagation directions along the $c$ axis and the $c$ plane, in spite of the very close wave vector to the Brillouin-zone center. This energy difference cannot be explained by a usual Raman-scattering scenario at this stage.

We present a combined experimental and theoretical study of the effects of pressure on T_c of the hexagonal layered superconductors nH-CaAlSi (n = 1, 5, 6), where nH labels the different stacking variants that were recently discovered. Experimentally, the pressure dependence of T_c has been investigated by measuring the magnetic susceptibility of single crystals up to 10 kbar. In contrast to previous results on polycrystalline samples, single crystals with different stacking sequences display different pressure dependences of T_c. 1H-CaAlSi shows a decrease of T_c with pressure, whereas 5H and 6H-CaAlSi exhibit an increase of T_c with pressure. Ab-initio calculations for 1H, 5H and 6H -CaAlSi reveal that an ultrasoft phonon branch associated to out-of-plane vibrations of the Al-Si layers softens with pressure, leading to a structural instability at high pressures. For 1H-CaAlSi the softening is not sufficient to cause an increase of T_c, which is consistent with the present experiments, but adverse to previous reports. For 5H and 6H the softening provides the mechanism to understand the observed increase of T_c with pressure. Calculations for hypothetical 2H and 3H stacking variants reveal qualitative and quantitative differences., Comment: 6 pages, 5 figures

A complex structure of the superconducting order parameter in $L{n}_{2}{\mathrm{C}}_{3}$ ($Ln=\mathrm{La},\mathrm{Y}$) is demonstrated by muon spin relaxation measurements in their mixed state. The muon depolarization rate [${\ensuremath{\sigma}}_{v}(T)$] exhibits a characteristic temperature dependence that can be perfectly described by a phenomenological double-gap model for nodeless superconductivity. While the magnitude of two gaps is similar between ${\mathrm{La}}_{2}{\mathrm{C}}_{3}$ and ${\mathrm{Y}}_{2}{\mathrm{C}}_{3}$, a significant difference in the interband coupling between those two cases is clearly observed in the behavior of ${\ensuremath{\sigma}}_{v}(T)$.

Inelastic x-ray scattering and $ab$-$initio$ calculation are applied to investigate the lattice dynamics and electron-phonon coupling of the ternary silicide superconductor CaAlSi ($P/bar{6}m2$). A soft c-axis polarized mode is clearly observed along the $/Gamma$-$A$-$L$ symmetry directions. The soft mode is strongly anharmonically broadened at room temperature, but, at 10 K, its linewidth narrows and becomes in good agreement with calculations of linear electron-phonon coupling. This establishes a coherent description of the detailed phonon properties in this system and links them clearly and consistently with the superconductivity., Comment: 4 pages, 4 figures, to be published in Phys. Rev. B (Rapid Communications)

We report muon spin relaxation measurements on two Ti3+ containing perovskites, LaTiO3 and YTiO3, which display long range magnetic order at low temperature. For both materials, oscillations in the time-dependence of the muon polarization are observed which are consistent with three-dimensional magnetic order. From our data we identify two magnetically inequivalent muon stopping sites. The muon spin relaxation results are compared with the magnetic structures of these compounds previously derived from neutron diffraction and muon spin relaxation studies on structurally similar compounds., Comment: 11 pages, 4 figures

A complex structure of the superconducting order parameter in Ln2C3 (Ln=La,Y) is demonstrated by muon spin relaxation measurements in their mixed state. The muon depolarization rate sigma v(T)] exhibits a characteristic temperature dependence that can be perfectly described by a phenomenological double-gap model for nodeless superconductivity. While the magnitude of two gaps is similar between La2C3 and Y2C3, a significant difference in the interband coupling between those two cases is clearly observed in the behavior of sigma v(T).

Tunneling spectroscopy using a break-junction technique has been conducted to determine the superconducting gap structure of the ternary silicide-layered superconductor CaAlSi with and without superstructure. We find that the tunneling conductance in CaAlSi shows a single gap feature, which can be described by the BCS density of states. The gap size $\ensuremath{\Delta}$ obtained from the tunneling conductance in CaAlSi without superstructure is estimated to be approximately $1.0\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$, corresponding to a weak-coupling gap ratio. On the other hand, for a specimen with superstructure, the largest gap, $\ensuremath{\Delta}=1.5\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$, significantly deviates from the BCS value, indicating strong-coupling superconductivity. These results demonstrate systematic variations in the pairing interaction with superstructure formations, which are consistent with heat capacity measurements.

We have succeeded in growing a phase in $\mathrm{CaAlSi}$ with Al and Si atoms being distributed regularly in the $\mathrm{AlSi}$ layer corresponding to the ${\mathrm{B}}_{2}$ plane in the ${\mathrm{AlB}}_{2}$-type structure without a superlattice along the $c$ axis. The field-induced magnetic response in a phase exhibits an almost isotropic characteristic for the respective crystal axis. Moreover, the $2\mathrm{\ensuremath{\Delta}}(0)∕{k}_{\mathrm{B}}{T}_{\mathrm{c}}$ and $\mathrm{\ensuremath{\Delta}}{C}_{\mathrm{el}}∕{\ensuremath{\gamma}}_{\mathrm{N}}{T}_{\mathrm{c}}$ estimated by heat capacity measurements are $\ensuremath{\sim}3.5$ and $\ensuremath{\sim}1.4$, respectively, indicating a BCS superconductor with a weak coupling. Although $\mathrm{CaAlSi}$ has a two-dimensional layered structure, these results strongly suggest that the superconductivity of the phase in $\mathrm{CaAlSi}$ is derived from a three-dimensional electronic ground state such as a conventional $s$-wave superconductor, which is markedly different from those of superstructured $\mathrm{CaAlSi}$.

The response of vortex state to the magnetic field in ${\mathrm{Nb}}_{3}\mathrm{Sn}$ is probed using muon spin rotation and small-angle neutron scattering. A transformation of vortex structure between hexagonal and squared lattice is observed over a relatively low field range of $2\char21{}3\phantom{\rule{0.3em}{0ex}}\mathrm{T}$. The gradual increase of the magnetic penetration depth with increasing field provides microscopic evidence for anisotropic (or multigapped) $s$-wave pairing suggested by the Raman scattering experiment. This result renders need for careful examination on the difference of electronic properties between ${\mathrm{Nb}}_{3}\mathrm{Sn}$ and ${\mathrm{V}}_{3}\mathrm{Si}$.

We report on the magnetic penetration depth, lambda, in a type II superconductor NbB_{2+x} determined by muon spin rotation method. We show in the sample with x=0.1 that lambda at 2.0 K is independent of an applied magnetic field. This suggests that the superconducting order parameter in NbB_{2+x} is isotropic, as expected for conventional BCS superconductors. Meanwhile, the superconducting carrier density (proportional to lambda^{-2}) exhibits an interesting tendency of increase with increasing T_c (where T_c varies with x). Possible origin of such behavior is discussed in comparison with the case of exotic superconductors., 11 pages, 5 figures, submitted to J. Phys. Soc. Jpn

The purpose of this work is to provide a method to increase the number of connectable devices for the Fieldbus. We have proposed a new signal transmitting method, which has features to reduce driven current during non-transmission and raise average driven current to a level which generates the required signal voltage during transmission. In this method, since the average current changes according to whether the transmission occurs or not, vibrations are generated on the bus. The frequency of the bus vibration can be filtered out. But this filter influences on the low-frequency part of the receiving signal, and also degrades the jitter of the digitalized signal. In this paper, we simulated the influence on the receiving signal by the jitter and obtained the filter characteristics that reduces the influence of the jitter to a minimum, and showed that there is no problem to the new signal transmitting method. >

This paper introduces FRONTIER-1; the first chip developed for Fieldbus Interface which integrates complete functions including the modem and the transceiver required for implementing H1 Fieldbus Physical Layer Specification (Wire media, Voltage mode, 31.25 kbps). FRONTIER-1 contains high-voltage bipolar devices to drive the bus, analog circuits such as Op-amps, comparators and a voltage reference for drive control, voltage regulation and filters, and CMOS for the modem circuits. The integration of the transceiver and the modem was accomplished by using high-voltage Bi-CMOS process technology. On transmitting, FRONTIER-1 adds the frame delimiters and preambles to the messages supplied by a host CPU, generates FCS (Frame Check Sequence), and performs Manchester encoding. Transmitted digital signal is converted to the analog signal on the bus. On receiving, the signal on the bus is digitized, and modem circuits decode Manchester data and check FCS, and a host CPU reads the messages. >

Research has been conducted into ways of enabling wiring operations to be performed on overhead power lines without shutting off the power. This research has culminated in the development of a method called the bypass cable method. One of the bypass cables used in this method has a built-in polyaramide resistor for additional strain resistance, providing greatly improved performance. The development and spread of the bypass cable method has enabled work-related power shut-offs to be reduced to one-fourth the number required five years beforehand, and each year this level continues to decline. >

Retinal ischemia-reperfusion injury induces apoptosis of retinal neurons. The purpose of this study was to examine the association of c-Jun, caspase-1, -2, and -3 immunoreactivities and neuronal apoptosis in the retinal ganglion cell layer (GCL) and to study the effects of intravitreal brain-derived neurotrophic factor (BDNF) on the expression of these gene products in a rat model of retinal ischemia-reperfusion injury.After 60 minutes of ischemia, eyes were enucleated after 3, 6, 12, 24, and 168 hours of reperfusion. The numbers of c-Jun-, caspase-1-, caspase-2-, caspase-3, and TdT-dUTP terminal nick-end labeling (TUNEL)-positive cells in the GCL were counted. Recombinant human BDNF (5 microg) or vehicle was injected intravitreally immediately after reperfusion. At 6, 24, and 168 hours, the numbers of immunoreactive cells in BDNF- and vehicle-treated groups were compared.Expression of c-Jun and caspase-2 was found in dying cells in flat-mounted retinas. The numbers of caspase-1- and caspase-3-positive cells were fewer than c-Jun- or caspase-2-positive cells. Cell death in the retinal GCL was suppressed by an intravitreal injection of BDNF. The numbers of TUNEL- and caspase-2-positive cells were lower in the BDNF-treated group at 6 hours after reperfusion (P0.01). The number of c-Jun-positive cells in the treated retinas was not altered by the treatment.Expression of c-Jun and caspase-2 is associated with neuronal cell apoptosis in the GCL. Suppression of caspase-2 expression may explain the neuroprotective effects of BDNF.

To study the role of caspase-like proteases, especially roles of more extensively characterized caspase-1 and caspase-2, in apoptotic photoreceptor cell degeneration in Royal College of Surgeons (RCS) rats.Both RCS and Sprague-Dawley rats were used. Cryosections of the retinas at various postnatal times were immunostained with antibodies against caspase-1 (interleukin-1beta-converting enzyme, ICE) and caspase-2 (Nedd2/Ich-1). Double staining with TdT-dUTP terminal nick-end labeling (TUNEL), propidium iodide, and the antibodies was also performed. To evaluate the time course of protein expression, western blot analysis was carried out. The temporal profile of caspase-like protease activity was studied using a fluorogenic tetrapeptide substrate, acetyl-tyrosyl-valyl-alanyl-aspartic acid alpha (4-methyl-coumaryl-7-amide) (Ac-YVAD-MCA). Intravitreal injection of a caspase-1 inhibitor, acetyl-tyrosyl-valyl-alanyl-aspartic-aldehyde (Ac-YVAD-CHO), at postnatal days 21 (P21) and P26 was performed to see if this caused a decrease in apoptotic cell number at P28.TUNEL-positive photoreceptors of RCS rats stained strongly with antibodies against caspase-1 and caspase-2. Double staining studies revealed that caspase-1 and caspase-2 were coexpressed in apoptotic cells. Western blot analysis showed that active forms of caspase-1-like and caspase-2-like proteases were upregulated at P28, concurrent with the peak in TUNEL-positive cells. The enzymatic activity of caspase-1-like protease was elevated in RCS rat retinas at P28, and the inhibitor of caspase-1 transiently reduced the number of the apoptotic photoreceptors.Activation of caspase-like proteases plays an important role in photoreceptor apoptosis of RCS rats.

To study whether cell type-specific death occurs in retinal ischemia-reperfusion injury and the possible roles of p16INK4 in the determination of cell death.Retinal ischemia-reperfusion injury was induced in rats by a ligation method. After 1 hour of ischemia and a time of reperfusion that varied, rat eyes were enucleated. Cell death in the retina was studied by the TdT-dUTP terminal nick-end labeling method and propidium iodide (PI) staining. Electron microscopic observation of the retina was also performed. Immunohistochemical studies using antibodies against syntaxin and calbindin were performed to detect amacrine cells and horizontal cells, respectively, and immunohistochemical studies using an antibody against p16INK4 were performed to study whether this cell cycle-related protein was expressed in dying cells.Most of the calbindin-positive horizontal cells in the outer aspect of the inner nuclear layer (INL) showed morphologic features of necrosis. In contrast, syntaxin-positive amacrine cells in the inner aspect of the INL showed features of apoptosis. Of 320 calbindin-positive horizontal cells, only 11 (3.4%) showed positive PI staining. Those calbindin-positive, horizontal cells were p16INK4 positive. In contrast, 746 of 910 (82.0%) syntaxin-positive amacrine cells showed condensed PI staining, and none were p16INK4 positive.Expression of p16INK4 may regulate the fate of retinal neurons in ischemia-reperfusion injury, and cell type-specific death thus occurs in the retina after such injury.

We report on the detailed crystal structure and superconducting properties in the single-crystalline SrAlSi by means of synchrotron X-ray diffraction technique and systematic magnetization measurements. Although SrAlSi exhibits a clear no sign of superlattice reflection, the anisotropic parameter for magnetic response in SrAlSi is almost equivalent to that of superstructured CaAlSi. It is inferred from these results that the electronic ground state in SrAlSi shows quasi-two-dimensional characteristics, and its dimensionality is irrelevant to the superstructured system.

Toremifene (TOR) is a new antiestrogenic agent, a triphenylethylene derivative that was developed as an alternative to tamoxifene (TAM). TOR has been observed to be more effective than TAM with milder toxicity at high doses. We examined the in vitro combination-effect of TOR with cyclophosphamide, adriamycin, 5-fluorouracil and three drug mixture (CAF) on the growth of various human mammary carcinomas. The combination shows a semi-additive or additive growth inhibitory effect on all estrogen positive cells used here except one cell line. In particular, the additive or synergic combination-effect was observed on TAM resistant cells. Furthermore, TOR exhibits a chemosensitizing activity in ADR-resistant cells by expressing P-glycoprotein coded by MDR-1 (multidrug resistance gene). The chemosensitizing activity is dose-dependent of TOR. As described above, the combination of TOR with CAF shows more than a semi-additive effect in this experiment. In conclusion, the addition of high-dose TOR to CAF therapy might be useful for advanced/recurrent breast cancer.

To evaluate the protective effects of recombinant adult T-cell leukemia- derived factor (ADF)-human thioredoxin against ischemia-reperfusion injury in the rat retina.Retinal ischemia was induced in rats by increasing the intraocular pressure to 110 mm Hg for 60 minutes. Various doses of recombinant human ADF (rhADF) or vehicle were administered intravenously before ischemia induction and immediately after reperfusion. The degree of retinal damage was assessed by electroretinogram (ERG) recording, by measuring the inner retinal thickness, and by counting the number of TdT-dUTP terminal nick-end labeling (TUNEL)-positive cells in the inner nuclear layer.The amplitudes of the ERG b-wave and oscillatory potentials were increased significantly by treatment before ischemia and after reperfusion with 0.5 mg or 5 mg rhADF and by treatment after reperfusion with 1 mg rhADF, compared with those of vehicle-treated control rats (P0.01). On day 28 after reperfusion, the thickness of the inner retina of control rats and of rats treated before ischemia and after reperfusion with 0.5 mg rhADF were 46.1+/-6.4 microm and 78.5+/-8.9 microm, respectively (P0.01). The number of TUNEL-positive cells on days 1 and 2 after reperfusion was decreased significantly by treatments with 0.5 mg rhADF compared with the number of TUNEL-positive cells in control rats (P0.01).Electrophysiologic and histologic studies showed that ischemia for 60 minutes produces severe damage in vehicle-treated control rat retina, particularly in the inner retinal layer. Intravenous injection of rhADF protects the rat retina from ischemia-reperfusion injury.

Combined androgen blockade using a pure antiandrogen in association with a LHRH agonist or surgical castration is the most logical approach. This paper demonstrated that flutamide combined with leuprorelin acetate produced a significant reduction in the growth rate of Dunning R3327-H prostatic adenocarcinoma. Dunning R3327-H prostatic adenocarcinoma, provided by Dr. Norman H. Altmann (University of Miami, USA) was subcutaneously inoculated into the lateral region of male Copenhagen x Fischer F1 hybrid rat abdomen. The efficacy of the tumor growth rate was evaluated by measuring tumor size at 10 weeks after the inoculation. Flutamide was orally administered for 10 weeks and leuprorelin acetate was subcutaneously administered every 4 weeks. The effective dose of flutamide and leuprorelin acetate was determined in preliminary studies, and the following doses were used in the study; 15 mg/kg for flutamide, 0.1 mg/kg or 0.4 mg/kg for leuprorelin acetate. In combination of flutamide with leuprorelin acetate at 0.1 mg/kg and 0.4 mg/kg, the tumor inhibition was 94% and 97%, respectively. In addition, the weight of accessory sex organs coincided with the antitumor effect. Taking the above results into consideration, combined androgen blockade using flutamide and leuprorelin acetate may have some beneficial effect on prostatic cancer.

To investigate whether cell cycle-related genes play a role in neuronal cell death in retinal ischemia-reperfusion injury.Retinal ischemia-reperfusion injury was induced in rats by a ligation method and also by increasing the intraocular pressure. After 1 hour-of ischemia, cell death in the retina was studied using the TdT-dUTP terminal nick-end labeling (TUNEL) method, propidium iodide (PI) staining, DNA ladder formation, and ultrastructural studies. Immunohistochemical studies using antibodies against cell cycle-related genes were conducted. Changes in expression of cyclin D1 mRNA were quantitated using competitive quantitative polymerase chain reaction.At 3 hours after reperfusion, cells in the ganglion cell layer were the first to die, followed by those in the inner nuclear layer (at 6 hours) and outer nuclear layer (at 9 hours). Ultrastructural studies revealed condensed nuclei and relatively preserved mitochondria; DNA ladder formation was also detected. Immunostaining was positive for the cell cycle-related gene products c-Jun, cyclin B1, and cyclin D1. The time course of TUNEL-positive cells and that of cells positive for c-Jun or cyclin D1 in the inner nuclear layer was similar. A double-labeling study, using PI or TUNEL, and immunohistochemical analysis revealed that dying cells expressed c-Jun and cyclin D1, whereas cyclin B1 expression was observed in Müller cells. Quantitation of cyclin D1 mRNA revealed an approximate 4-fold increase at 24 hours after reperfusion.Aberrant expression of cell cycle-related genes may play an important role in the cell death that accompanies retinal ischemia-reperfusion injury.

When high-strength concretes are conveyed by pumping, the pumping pressure may increase and the flowability of high-fluidity concrete may be greatly decreased. This is a problem for construction of concrete-filled tubular steel columns. In this study, pumping tests and filling tests of steel tubular model columns with several kinds of high-fluidity concrete having a water/cement ratio of 30% were conducted. Silica fume results in better pumpability. The pressure loss reflects good correlation to the plastic viscosity of the concrete calculated from the time taken for it to discharge from an inverted slump cone. When the concretes used in the tests were pumped into tubular columns, the cavity area under the diaphragm plates was less than 10% and the core strength obtained at 91 days was over 80 N/sq mm. If the slump flow of concrete at the top of the column is more than 45 cm, it can be expected that the column will be filled well. The pressure of concrete at the bottom of the column is approximately 1.2 times the head pressure.

Epstein-Barr virus associated T-Cell lymphoma mimicking malignant histiocytosis (MH) has been previously reported. We selected 10 autopsy cases of extranodal lymphoma or histiocytic tumor, which showed an EBV presence in the tumor cells as well as a fulminant clinical course. The detailed clinicopathologic features were thus clarified. A retrospective study was performed on ten adult patients, eight males and two females, and almost all cases presented with a fulminant clinical course, revealing pancytopenia, liver dysfunction and disseminated intravascular coagulopathy. Immunophenotypic and genotypic studies along with in situ hybridization (ISH) were performed. The autopsy findings mainly showed extra nodal involvement in the liver (10 patients), spleen (9 patients), intestinal tract (5 patients), bone marrow (5 patients), nasal cavity, lungs, adrenal glands, kidneys (2 patients) and brain. Histologically atypical pleomorphic lymphoid cells were observed to infiltrate with reactive histiocytes, some of which showed hemophagocytosis. Based on the histological and clinical findings, diagnosis of malignant histiocytosis was made. ISH showed an EBV-presence in almost all the tumor cells. The immunophenotype and/or genotype studies demonstrated T-cell lymphoma (2 patients), Histiocytic tumors (2 patients), B-cell lymphoma (1 patients), natural killer (NK) cell lymphoma (3 patients), and T/NK lymphoma (2 patients), in which T or NK could not be confirmed, due to a lack of fresh materials. Based on the above findings, the histological appearance of EBV-associated MH previously defined was shown to be common to extra-nodal malignant lymphomas having origin in various organs, although the cytological and genetic features were heterogenous.

The authors report a case of bacterial intracranial aneurysm associated with infective endocarditis. A 48-year-old male was admitted on March 26, 1994, with complaints of difficulty in speaking and mild swelling of the right leg following mild fever. On examination he showed motor aphasia and mild weakness of the right upper and lower limbs. Cardiac auscultation revealed a grade 3/6 holosystolic murmur. Laboratory data revealed signs of infection through white blood cell count and CRP. Enterococcus faecalis was isolated from the blood culture at the time of admission. A computerized tomographic (CT) scan and magnetic resonance (MR) imaging showed a round mass with perifocal edema. Angiography revealed an aneurysm from the precentral artery of the left middle cerebral artery. A mycotic aneurysm due to bacterial endocarditis was diagnosed. The patient was treated with high doses of antibiotics. However, angiography 2 weeks after the initial study demonstrated the enlargement of the aneurysm and severe narrowing of the angular artery. On April 19, excision of the aneurysm was performed. Operative findings showed degeneration and thickening of the walls of the aneurysm. After the operation, antibiotic therapy was continued. The patient was asymptomatic upon discharge and has continued to do well. Repeated angiography on September 12 showed no further aneurysm. There is a danger of rupture in mycotic aneurysm due to bacterial endocarditis. It is important to repeat angiography and to manage the primary disease. If an aneurysm enlarges with serial angiography, it should be treated surgically without further delay.

NK622, a novel tamoxifen(TAM) analog with nonsteroidal structure is an antiestrogenic drug with less toxicity compared with that of TAM. We studied the in vivo antitumor activity against human breast cancer xenografts in nude mice. NK 622 significantly inhibited the growth of estrogen-dependent Br-10 breast cancer but not inhibited the growth of estrogen-independent MC-2-JCK and MC-5-JCK when orally administered once daily for 14 days at the maximum tolerated dose (200mg/kg/day). The dose of NK622 in animal studies was calculated by measuring plasma level in patients receiving 40 mg/body/day oral treatment and clinically equivalent dose (CED) was determined. At the calculated CED, NK622 significantly inhibited the growth of Br-10. These results indicate that NK622 is a promising drug comparable to TAM because of the growth inhibition of estrogen-dependent breast cancers.

The full-potential linear augmented plane-wave calculations have been applied to investigate the systematic change of electronic structures in CaAlSi due to different stacking sequences of AlSi layers. The present ab-initio calculations have revealed that the multistacking, buckling and 60 degrees rotation of AlSi layer affect the electronic band structure in this system. In particular, such a structural perturbation gives rise to the disconnected and cylindrical Fermi surface along the M-L lines of the hexagonal Brillouin zone. This means that multistacked CaAlSi with the buckling AlSi layers increases degree of two-dimensional electronic characters, and it gives us qualitative understanding for the quite different upper critical field anisotropy between specimens with and without superstructure as reported previously., Comment: 4 pages, 4 figures, to be published in J. Phys. Soc. Jpn

We report on magnetic, transport, specific heat and tunneling measurements of NbB 2 with the maximum superconducting critical temperature T c ∼10 K. The essential superconducting properties have been investigated through mapping out the critical field phase diagram, from which it is turned out to be type II superconductor with a small Ginzbrug–Landau parameter κ∼2.2. Both the tunneling and specific heat measurements indicate that our NbB 2 specimen has a single gap and s -wave pairing symmetry with a weak-coupling limit. The electron–phonon coupling constant is estimated to be λ ep =0.71±0.02, suggesting that the maximum T c of NbB 2 can be explained by the McMillan formula.

We report on muon spin rotation/relaxation (µSR) studies of the cuprate mineral melanothallite, Cu2OCl2, over a temperature range between 4.1 and 300 K. This compound has a pyrochlore-like corner-shared OCu4 tetrahedral network with an S = 1/2 system. The magnetic susceptibility shows a broad maximum around 140 K and drops at 70 K. In the µSR measurement, we observed clear muon spin precession spectra below 70 K that is evidence for a long-range magnetic ordered state. However, the time spectra also exhibit exponential damping even in the ordered state, suggesting a possible influence of geometrical frustration in this compound. This renders the need for careful examination of the magnetic structure of the ordered state.

846 Background: It has been reported that the antiestrogen agent (SERM) has a resistance relief function when it bind to P-glycoprotein (Pgp) and supresses pumping action. A blood concentration of ...