Tatsuo Nakajima, Satoru Nakajima, Takeshi Izawa, Tomoko Kashiwabara, Y. MUNEZUKA,
A new series of cyanoamidines, N-arylalkyl-N'-cyano-3-pyridinecarboxamidines was synthesized and evaluated for inhibitory effects on 40 mM KCl-induced contraction and norepinephrine (NE)-induced contraction of rat aorta strips. The N-phenethyl cyanoamidine 4c showed potent vasodilatory action. Further in vitro screening program using 4c as a lead compound resulted in the discovery of highly potent N-[2-(2-chlorophenyl)ethyl]-N'-cyano-3-pyridinecarboxamidine (5j). Compound 5j induced the greatest increase ...
Tópico(s): Synthesis and Biological Evaluation
1994 - Pharmaceutical Society of Japan | Chemical and Pharmaceutical Bulletin
Eriko Ohshima, Masae Kikuchi, Fujio Izumi, Kenji Hiraga, Takeo Oku, Satoru Nakajima, Naoyuki Ohnishi, Yukio Morri, Satoru Funahashi, Yasuhiko Syono,
The crystal structure of orthorhombic TlSr2CuOy was determined by Rietveld analysis of neutron powder diffraction data with the aid of electron diffraction and high-resolution electron microscopy. We found that oxygen vacancies are formed along the a-direction in a CuO2−z sheet, which is consistent with a superstructure of twice the subcell along the b-direction. CuO6 octahedra and CuO4 square planes alternate along the b-direction by sharing their corners in accordance with the ordered oxygen vacancies ...
Tópico(s): Microwave Dielectric Ceramics Synthesis
1994 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masafumi Fujimoto, Motohiko Ueda,
In A7r5 smooth muscle cell suspensions, 12-deoxyphorbol 13-isobutyrate (DPB) and phorbol 12,13-dibutyrate (PDB), active phorbol esters for protein kinase C (PKC), increased the intracellular Ca2+ concentration ([Ca2+]i), but 4 alpha-PDB, an inactive phorbol ester, did not. Digital images of the fura 2 fluorescence from single cells revealed that DPB caused elevation of Ca2+ in localized peripheral regions, followed by expansion of this elevated Ca2+ level throughout the cytoplasm. High K+ also induced ...
Tópico(s): Neurobiology and Insect Physiology Research
1993 - American Physical Society | AJP Cell Physiology
Hiroshi Yamaguchi, Satoru Nakajima, Yuji Kuwahara, H. Ōyanagi, Yasuhiko Syono,
Abstract The local structure of Tl 2 Ba 2 CuO y (Tl2201) has been investigated by extended X-ray absorption fine structure (EXAFS) on the Cu K-edge. The result for the high- T c sample with T c =70 K indicates a splitting of Cu-O bondlengths in the CuO 2 plane, which shows a strong temperature dependence over a wide temperature range well above T c , although the crystallographical symmetry of the unit cell is tetragonal. The splitting is evaluated from the filtered EXAFS by the beat-node method, and ...
Tópico(s): Superconductivity in MgB2 and Alloys
1993 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Takeo Oku, K. Nagase, Norio Kobayashi, Daisuke Shindo, K. Hiraga,
Abstract The oxygen contents of oxygen-annealed T1 single layer systems were determined by iodometric titration. The oxygen contents, w , of T1Ba 2 Ca 1- x Y x Cu 2 O w increased with Y concentration, x , substituted for Ca. Oxygen vacancy, y , was estimated to be about. y =0.3 in oxygen-annealed T1Ba 2 Ca n -1 Cu n O 2 n +3- y ( n =2, 3, 4). The Cu valence of oxygen-annealed T1Ba 2 Ca n -1 Cu n O 2 n +3- y is calculated to be about 2.2+, if the hole is introduced only in the CuO 2 pyramidal sheets. Square planar ...
Tópico(s): Copper Interconnects and Reliability
1991 - Elsevier BV | Physica C Superconductivity
Norio Kawahara, K. NOZAWA, Mineo Yamazaki, Satoru Nakajima, K. Kawai,
Novel compounds designated emethallicins B (1), C (2), and D (3), along with emethallicin A (4), were isolated from the mycelium of the heterothallic fungus, Emericella heterothallica (mating type a). The structures of emethallicins B (1), C (2), and D (3) were determined on the basis of spectroscopic and chemical investigations. Emethallicins B (1) and C (2) are epitetrathiodioxopiperazines, which have the same basic carbon skeleton as apoaranotin (19) and acetylaranotin (17), respectively, whereas emethallicin ...
Tópico(s): Microbial Natural Products and Biosynthesis
1990 - Pharmaceutical Society of Japan | Chemical and Pharmaceutical Bulletin
Masae Kikuchi, Satoru Nakajima, Yasuhiko Syono, K. Nagase, Reiko Suzuki, Tsuyoshi Kajitani, Norio Kobayashi, Yoshio Mutô,
Tópico(s): Microwave Dielectric Ceramics Synthesis
1990 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, K. Nagase, Takeo Oku, Norio Kobayashi, Daisuke Shindo, K. Hiraga,
The Tc and oxygen content of TlBa2CaCu2Oy have been investigated by quenching experiments, in which the heat-treated samples were dropped into liquid nitrogen. The oxygen loss, v, of TlBa2CaCu2Oyo − v was determined by thermogravimetry in a nitrogen atmosphere using an oxygen-annealed specimen of TlBa2CaCu2Oyo and also by measurements of the weight differences before and after quenching. Tc increased from 80 K of the oxygen-annealed specimen up to about 110 K with increasing oxygen loss up to v = 0. ...
Tópico(s): Inorganic Fluorides and Related Compounds
1990 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Norio Kobayashi, Yoshio Mutô,
Tc and the unit cell dimensions of TlBa2Ca1−xRExCu2O7 (where RE is Nd, Gd or Y) have been investigated for a wide substitution range. The tetragonal unit cell dimensions c and a decreased and increased, respectively, with the substitution of Ca with RE. An as-prepared specimen of TlBa2CaCu2O7 with Tc=80 K was found to be in an over-doping state and Tc increased to 100 K with increasing x up to x=0.2-0.35, where it began to decrease and became nonsuperconducting at x=0.4-0.5.
Tópico(s): Iron-based superconductors research
1990 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Takeo Oku, Daisuke Shindo, K. Hiraga, Norio Kobayashi, M. Iwasaki, Yoshio Mutô,
Bulk specimens of high Tc superconductors of TlBa2Can − 1CunO2n + 3 (n = 2 − 5) have been synthesized by heat treatment up to 10 hours. Crystal structures were analyzed by X-ray powder diffraction and high resolution electron microscopy, and superconducting properties were determined by resistivity and DC susceptibility measurements. Tc increases with increasing number of Cu layers up to n = 4, where it turns down.
Tópico(s): Superconductivity in MgB2 and Alloys
1989 - Elsevier BV | Physica C Superconductivity
Masae Kikuchi, Tsuyoshi Kajitani, Teruo Suzuki, Satoru Nakajima, Kenji Hiraga, Norio Kobayashi, Hideo Iwasaki, Yasuhiko Syono, Yoshio Mutô,
Superconducting oxides of Tl 2 Ba 2 Ca n -1 Cu n O 2 n +4 with n =1, 2 and 3 were synthesized, and their structure and chemical composition were examined by X-ray powder diffraction, EPMA, Rietveld analysis and electron microscopy. Partial substitution of Tl with Ca was confirmed, but the production of holes in Cu layers expected from this substitution was rather small for a 120 K superconductor. Charge transfer of Tl 3-δ -Cu 2+δ would provide both the hole in the Cu-O bond required for high T c and ...
Tópico(s): Inorganic Fluorides and Related Compounds
1989 - Institute of Physics | Japanese Journal of Applied Physics
Daisuke Shindo, K. Hiraga, Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Norio Kobayashi, K. Hojou, Takeshi Soga, S. Furuno, H. Otsu,
Abstract The fine structures of the oxygen K-edge in TlBa2Ca1-xYxCu2O7 (x=0, 0.8 and 1.0) with single Tl-O laye rs were investigated by electron energy loss spectroscopy (EELS). The peak corresponding to the hole state near the Fermi energy decreases with the increase of the Y content. Although a small density of the hole state is observable in the compound Tl1Ba2Ca0.2Y0.8Cu2O7, it s hows the semiconducting character. It was pointed out that the decrease of the hole content mainly results in the transition ...
Tópico(s): Superconductivity in MgB2 and Alloys
1989 - Elsevier BV | Physica C Superconductivity
Masae Kikuchi, Satoru Nakajima, Yasuhiko Syono, K. Hiraga, Takeo Oku, Daisuke Shindo, Norio Kobayashi, M. Iwasaki, Yoshio Mutô,
The bulk superconductor Tl2Ba2Ca3Cu4O12 with Tc (onset) above 112 K has been prepared and structure and chemical composition were examined by X-ray powder diffraction, analytical (EDX) and high resolution electron microscopy. Unit cell dimensions for the tetragonal cell determined by the least squares method are a = 3.853 (1) Å, c=41.98 (3) Å. The transition temperature, Tc, of the double layered Tl system increases with the number of Cu-O layers (n) up to n = 3, while it turns down at n = 4.
Tópico(s): Rare-earth and actinide compounds
1989 - Elsevier BV | Physica C Superconductivity
M. Iwasaki, Norio Kobayashi, Masae Kikuchi, Tsuyoshi Kajitani, Yasuhiko Syono, Yoshio Mutô, Satoru Nakajima,
The electrical resistance was measured on a Tl-Ba-Ca-Cu-O single crystal. From X-ray diffraction the composition of the sample is expected to be Tl:Ba:Ca:Cu=1:2:1:2. The superconducting transition temperature Tc is 106 K. The upper critical field Hc2 shows anisotropy, that is, (-dHc2/dT)Tc for H⊥c-axis and for H∥c-axis are 1.9 T/K and 0.2 T/K, respectively. The ratio of the former to the latter is 9.5. The low resistance part in the transition shows a thermally activated temperature dependence. The ...
Tópico(s): Superconducting Materials and Applications
1989 - Elsevier BV | Physica C Superconductivity
Satoru Nakajima, Masae Kikuchi, Takeo Oku, Norio Kobayashi, Teruo Suzuki, K. Nagase, K. Hiraga, Yoshio Mutô, Yasuhiko Syono,
Superconductivity was observed in La substituted Tl2Ba2CuO6. Both Tc and unit cell dimension, a, increase with increasing La concentration, indicating that an over-doping state in Tl2Ba2CuO6, which was due to charge transfer Tl3−t-(Cu-O)p as supported from XPS measurements, was relieved by La substitution for Ba.
Tópico(s): Rare-earth and actinide compounds
1989 - Elsevier BV | Physica C Superconductivity
Daisuke Shindo, Hiroshi Sato, G. L. Liedl, D. Perry, Kenji Hiraga, Makoto Hirabayashi, Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, K. Hojou, Takeshi Soga,
The fine structures of the oxygen K-edge in the Tl 1 Ba 2 Ca n -1 Cu n O 2 n +3 with single Tl-O layers were investigated by electron energy loss spectroscopy (EELS). The peak corresponding to the hole state near the Fermi energy was sensitive to the number of Cu-O layers and the direction of momentum excitation. It was shown that the hole content in Tl 1 Ba 2 Ca n -1 Cu n O 2 n +3 decreases with the increase of n ( n =2–4) and that most holes exist in the O 2p x , y orbitals of 2-dimensional Cu-O planes.
Tópico(s): Iron-based superconductors research
1989 - Institute of Physics | Japanese Journal of Applied Physics
Tsuyoshi Kajitani, Kenji Hiraga, Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Chizuko Kabuto,
Single crystals of superconducting oxide Tl2−xBa2+yCu3O10−z with x∼0.4, y∼0.4 and z∼0 were synthesized by the flux growth method. Mixtures of oxide powders having a nominal metal ratio Tl/Ba/Ca/Cu at 2/2/2/3 or 2/2/3/4 were heated at 1193 K in a pure oxygen atmosphere at 1 atm for 1 h and then cooled slowly. Crystal structures at room temperature, 180 K and 130 K were investigated by means of 4-circle X-ray diffraction measurement. Splitting of the oxygen site at 4e (0 0 z) with z∼0.28 to 16n(x 0 ...
Tópico(s): Inorganic Fluorides and Related Compounds
1989 - Elsevier BV | Physica C Superconductivity
Teruo Suzuki, Masayasu Nagoshi, Yasuo Fukuda, Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, M. Tachiki,
The valence state of Tl in TlBaCaCuO systems is studied using X-ray photoemission. The mechanism of hole formation is discussed in terms of the charge transfer. Our XPS data suggest that a charge transfer such as Tl3+ - [CuO]0 → Tl(3−δ)+ − [CuO]δ+ could occur in Tl2Ba2Can−1CunO2n+4(n=2, 3) with double [TlO] layers, but not in TlBa2CaCu2O7 with a single [TlO] layer.
Tópico(s): Superconductivity in MgB2 and Alloys
1989 - Elsevier BV | Physica C Superconductivity
Makoto Otsu, Masafumi Yamada, Satoru Nakajima, Miyuki Kida, Yoshihiro Maeyama, Norikazu Hatano, Nariaki Toita, Shunichiro Takezaki, Yuka Okura, Ryōji Kobayashi, Yoshinori Matsumoto, Osamu Tatsuzawa, F Tsuchida, Shunichi Kato, Masanari Kitagawa, Junichi Mineno, Michael S. Hershfield, Pawan Bali, Fabio Candotti, Masafumi Onodera, Nobuaki Kawamura, Yukio Sakiyama, Tadashi Ariga,
We here describe treatment outcomes in two adenosine deaminase (ADA)-deficiency patients (pt) who received stem cell gene therapy (SCGT) with no cytoreductive conditioning. As this protocol has features distinct from those of other clinical trials, its results provide insights into SCGT for ADA deficiency.Pt 1 was treated at age 4.7 years, whereas pt 2, who had previously received T-cell gene therapy, was treated at age 13 years. Bone marrow CD34(+) cells were harvested after enzyme replacement therapy ( ...
Tópico(s): RNA Interference and Gene Delivery
2015 - Springer Science+Business Media | Journal of Clinical Immunology
Satoru Nakajima, Takashi Tsukahara, Kazuo Minematsu,
We retrospectively studied clinical characteristics of 368 patients with cerebral artery dissections who were diagnosed in 172 Japanese hospitals. Of these patients, 130 (35%) presented with subarachnoid hemorrhage, 217 (59%) with cerebral infarctions, and 21 (6%) with transient ischemic attacks. We analyzed 109 (84%) subarachnoid hemorrhage cases caused by vertebrobasilar artery dissection to evaluate conservative and surgical treatment from the viewpoint of postoperative rerupture and infarction. ...
Tópico(s): Traumatic Brain Injury and Neurovascular Disturbances
2009 - Springer Science+Business Media | Acta neurochirurgica. Supplementum
Yu Nagase, Satoru Nakajima, Masataka Oku, Yasuhiko Iwasaki, Kazuhíko Ishihara,
In order to improve the biocompatibility of segmented polyurethane which has been widely used as a biomedical material, the synthesis of segmented poly(urethane-urea) containing phosphorylcholine (PC) moiety was carried out by using aromatic diamine monomer with PC unit. The obtained poly(urethane-urea)s were soluble in aprotic polar solvents such as NMP, DMSO and DMF, but insoluble in water, alcohol and acetone. In addition, it was confirmed from the results of blood contacting experiments that ...
Tópico(s): Polymer Surface Interaction Studies
2008 - Springer Nature | Polymer Journal
Minoru Yamaji, Susumu Inomata, Satoru Nakajima, Kimio Akiyama, Seiji Tobita, Bronisław Marciniak,
Photochemical properties of photoinduced ω-bond dissociation in p-benzoylbenzyl phenyl sulfide (BBPS) in solution were investigated by time-resolved EPR and laser flash photolysis techniques. BBPS was shown to undergo photoinduced ω-bond cleavage to yield the p-benzoylbenzyl radical (BBR) and phenyl thiyl radical (PTR) at room temperature. The quantum yield (Φrad) for the radical formation was found to depend on the excitation wavelength, i.e., on the excitation to the excited singlet states, S2 and ...
Tópico(s): Photochromic and Fluorescence Chemistry
2005 - American Chemical Society | The Journal of Physical Chemistry A
Yoshio Teki, Tetuya Toichi, Satoru Nakajima,
Abstract Syntheses, electronic structures in the ground state, unique photoexcited states, and spin alignment are reported for novel biradical 1 , which was designed as an ideal model compound to investigate photoinduced spin alignment in the excited state. Electron spin resonance (ESR), time‐resolved ESR (TRESR), and laser‐excitation pulsed ESR experiments were carried out. The magnetic properties were examined with a SQUID magnetometer. In the electronic ground state, two radical moieties interact ...
Tópico(s): Photochemistry and Electron Transfer Studies
2005 - Wiley | Chemistry - A European Journal
Toshiyuki Atou, M. Kawasaki, Satoru Nakajima,
Pressure and temperature dependence of electrical resistance of cobalt monoxide (CoO) was examined using a diamond anvil cell to 133 GPa and 20–300 K. At room temperature, drastic decrease in the electrical resistance (eight orders of magnitude) was observed in the pressure range of 43 to 63 GPa. Another small decrease in the electrical resistance was also observed at about 90 GPa. These results were consistent with the phase transitions at 43 GPa and 80–90 GPa previously observed by in situ X-ray ...
Tópico(s): Advanced materials and composites
2004 - Institute of Physics | Japanese Journal of Applied Physics
Abstract A novel photo-excited state with the intermediate spin (S = 1) arising from four unpaired spins and a nearly degenerate quintet (S = 2) excited state were detected for 1, which was designed utilizing the photo-excited triplet spin coupler by taking π-topology into account. The unique triplet state has an interesting electronic structure, which D value is reduced by the antiferromagnetic spin alignment between two radical spins through the excited spin coupler.
Tópico(s): Synthesis and Properties of Aromatic Compounds
2004 - Oxford University Press | Chemistry Letters
Yayoi Shiino, Satoru Nakajima, Yuji Ozeki, Takahiro Isono, Naoto Yamada,
We tested whether the human period 2 gene (hper2), one of the essential components of the circadian oscillator, might have influence on bipolar disorder. We screened 88 bipolar disorder patients and 127 controls, all of Japanese origin. Screening in the casein kinase I epsilon (CKIϵ) binding region of hper2, which was previously reported in familial advanced sleep-phase syndrome patients, with polymerase chain reaction amplification revealed four polymorphisms. One of the four polymorphisms had an ...
Tópico(s): Electromagnetic Fields and Biological Effects
2003 - Elsevier BV | Neuroscience Letters
Takeshi Shiota, Tohru Yamamori, K. Sakai, Machiko Kiyokawa, Teruki Honma, Masayoshi Ogawa, Kyohei Hayashi, N Ishizuka, Kenta Matsumura, Mariko Hara, Masafumi Fujimoto, Tomoji Kawabata, Satoru Nakajima,
We have already reported 7-oxo-4,7-dihydropyrazolo[1,5-a]pyrimidine-3-carboxylic acid derivatives, which are potent in vitro angiotensin II (AII) antagonists, but have no oral antihypertensive activity. Removal of the carboxylic acid and replacement of the heteroaromatic system afforded potent in vitro antagonists. Removal of the carbonyl oxygen and changing the position of the biphenyltetrazole substituent were critical to the display of oral activity. To improve the in vitro and oral activities, ...
Tópico(s): Synthesis and biological activity
1999 - Pharmaceutical Society of Japan | Chemical and Pharmaceutical Bulletin
Oxygen arrangement on Hg0.5Tl0.5Ba2CuOx (100) surface was studied by high-resolution electron microscopy. The {100} planes were found to be stable and to have preferred atomic surface. A surface structure model of Hg0.5Tl0.5Ba2CuOx was proposed and compared to the image calculations, which indicated the surface consists of Ba layers and oxygen atoms on the (Hg, Tl) layers. The present work indicates that the stable {100} planes of Hg-1201-type superconducting oxides would be suitable for the future ...
Tópico(s): Surface and Thin Film Phenomena
1999 - American Institute of Physics | Applied Physics Letters
Tópico(s): High-pressure geophysics and materials
1998 - Springer Nature | Journal of materials research/Pratt's guide to venture capital sources
T. Goto, Satoru Nakajima, Masae Kikuchi, Yasuhiko Syono, Tetsuo Fukase,
The end member of the Tl-based high-${\mathit{T}}_{\mathit{c}}$ cuprate ${\mathrm{TlBa}}_{2}$${\mathrm{YCu}}_{2}$${\mathrm{O}}_{7}$ (Tl1212) with the zero nominal hole number has been synthesized and studied by Cu/Tl NMR. The existence of the antiferromagnetic ordering was demonstrated by the Zeeman-splitted zero-field Cu spectra. Static parameters at the Cu site such as the hyperfine field ${\mathit{H}}_{\mathrm{Cu}}$=8.62 T and the quadrupolar frequency $^{63}\ensuremath{\nu}_{\mathit{Q}}$=20.44 MHz were ...
Tópico(s): Rare-earth and actinide compounds
1996 - American Physical Society | Physical review. B, Condensed matter