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Rojas-Sánchez JC, Oyarzún S, Fu Y, Marty A, Vergnaud C, Gambarelli S, Vila L, Jamet M, Ohtsubo Y, Taleb-Ibrahimi A, Le Fèvre P, Bertran F, Reyren N, George JM, Fert A. Spin to Charge Conversion at Room Temperature by Spin Pumping into a New Type of Topological Insulator: α-Sn Films. Phys Rev Lett 2016; 116:096602. [PMID: 26991190 DOI: 10.1103/physrevlett.116.096602] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Indexed: 06/05/2023]
Abstract
We present results on spin to charge current conversion in experiments of resonant spin pumping into the Dirac cone with helical spin polarization of the elemental topological insulator (TI) α-Sn. By angle-resolved photoelectron spectroscopy (ARPES), we first check that the Dirac cone (DC) at the α-Sn (0 0 1) surface subsists after covering Sn with Ag. Then we show that resonant spin pumping at room temperature from Fe through Ag into α-Sn layers induces a lateral charge current that can be ascribed to the inverse Edelstein effect by the DC states. Our observation of an inverse Edelstein effect length much longer than those generally found for Rashba interfaces demonstrates the potential of TIs for the conversion between spin and charge in spintronic devices. By comparing our results with data on the relaxation time of TI free surface states from time-resolved ARPES, we can anticipate the ultimate potential of the TI for spin to charge conversion and the conditions to reach it.
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Affiliation(s)
- J-C Rojas-Sánchez
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - S Oyarzún
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - Y Fu
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - A Marty
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - C Vergnaud
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - S Gambarelli
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - L Vila
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - M Jamet
- Université Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France
- CEA, Institut Nanosciences et Cryogénie, F-38000 Grenoble, France
| | - Y Ohtsubo
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
- Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - A Taleb-Ibrahimi
- UR1 CNRS, Synchrotron SOLEIL, Saint-Aubin, 91192 Gif sur Yvette, France
- Synchrotron SOLEIL, Saint-Aubin, 91192 Gif sur Yvette, France
| | - P Le Fèvre
- Synchrotron SOLEIL, Saint-Aubin, 91192 Gif sur Yvette, France
| | - F Bertran
- Synchrotron SOLEIL, Saint-Aubin, 91192 Gif sur Yvette, France
| | - N Reyren
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - J-M George
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - A Fert
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
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Matsuya Y, Ohtsubo Y, Tsutsumi K, Sasaki K, Yamazaki R, Date H. Quantitative estimation of DNA damage by photon irradiation based on the microdosimetric-kinetic model. J Radiat Res 2014; 55:484-93. [PMID: 24515253 PMCID: PMC4014172 DOI: 10.1093/jrr/rrt222] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 12/12/2013] [Accepted: 12/13/2013] [Indexed: 05/23/2023]
Abstract
The microdosimetric-kinetic (MK) model is one of the models that can describe the fraction of cells surviving after exposure to ionizing radiation. In the MK model, there are specific parameters, k and yD, where k is an inherent parameter to represent the number of potentially lethal lesions (PLLs) and yD indicates the dose-mean lineal energy in keV/μm. Assuming the PLLs to be DNA double-strand breaks (DSBs), the rate equations are derived for evaluating the DSB number in the cell nucleus. In this study, we estimated the ratio of DSBs for two types of photon irradiation (6 MV and 200 kVp X-rays) in Chinese hamster ovary (CHO-K1) cells and human non-small cell lung cancer (H1299) cells by observing the surviving fraction. The estimated ratio was then compared with the ratio of γ-H2AX foci using immunofluorescent staining. For making a comparison of the number of DSBs among a variety of radiation energy cases, we next utilized the survival data in the literature for both cells exposed to other photon types, such as (60)Co γ-rays, (137)Cs γ-rays and 100 kVp X-rays. The ratio of DSBs based on the MK model with conventional data was consistent with the ratio of γ-H2AX foci numbers, confirming that the γ-H2AX focus is indicative of DSBs. It was also shown that the larger yD is, the larger the DSB number is. These results suggest that k and yD represent the characteristics of the surviving fraction and the biological effects for photon irradiation.
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Affiliation(s)
- Yusuke Matsuya
- Graduate School of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo 060-0812, Japan
| | - Yosuke Ohtsubo
- Hokkaido PWFAC Sapporo-Kosei General Hospital, Kita-3 Higashi-8, Chuo-ku, Sapporo 060-0033, Japan
| | - Kaori Tsutsumi
- Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo 060-0812, Japan
| | - Kohei Sasaki
- Graduate School of Engineering, Kyoto University, Kyoto Daigaku-Katsura, Nishikyo-ku, Kyoto 615-8530, Japan
| | - Rie Yamazaki
- Graduate School of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo 060-0812, Japan
| | - Hiroyuki Date
- Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo 060-0812, Japan
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Mauchain J, Ohtsubo Y, Hajlaoui M, Papalazarou E, Marsi M, Taleb-Ibrahimi A, Faure J, Kokh KA, Tereshchenko OE, Eremeev SV, Chulkov EV, Perfetti L. Circular dichroism and superdiffusive transport at the surface of BiTeI. Phys Rev Lett 2013; 111:126603. [PMID: 24093286 DOI: 10.1103/physrevlett.111.126603] [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: 05/21/2013] [Indexed: 06/02/2023]
Abstract
We investigate the electronic states of BiTeI after the optical pumping with circularly polarized photons. Our data show that photoexcited electrons reach an internal thermalization within 300 fs of the arrival of the pump pulse. Instead, the dichroic contrast generated by the circularly polarized light relaxes on a time scale shorter than 80 fs. This result implies that orbital and spin polarization created by the circular pump pulse rapidly decays via manybody interaction. The persistent dichroism at longer delay times is due to the helicity dependence of superdiffussive transport. We ascribe it to the lack of inversion symmetry in an electronic system far from equilibrium conditions.
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Affiliation(s)
- J Mauchain
- Laboratoire de Physique des Solides, CNRS-UMR 8502, Université Paris-Sud, FR-91405 Orsay, France
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Ohtsubo Y, Mauchain J, Faure J, Papalazarou E, Marsi M, Le Fèvre P, Bertran F, Taleb-Ibrahimi A, Perfetti L. Giant anisotropy of spin-orbit splitting at the bismuth surface. Phys Rev Lett 2012; 109:226404. [PMID: 23368140 DOI: 10.1103/physrevlett.109.226404] [Citation(s) in RCA: 3] [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: 09/07/2012] [Indexed: 06/01/2023]
Abstract
We investigate the bismuth (111) surface by means of time and angle resolved photoelectron spectroscopy. The parallel detection of the surface states below and above the Fermi level reveals a giant anisotropy of the spin-orbit spitting. These strong deviations from the Rashba-like coupling cannot be treated in k·p perturbation theory. Instead, first principles calculations could accurately reproduce the experimental dispersion of the electronic states. Our analysis shows that the giant anisotropy of the spin-orbit splitting is due to a large out-of plane buckling of the spin and orbital texture.
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Affiliation(s)
- Y Ohtsubo
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin-BP 48, F-91192 Gif sur Yvette, France
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Abstract
We show that a metallic surface state is formed on Tl/Ge(111)-(1 × 1). The surface state forms electron pockets around K of the surface Brillouin zone. A first-principles calculation reveals that the electron pockets are composed of a single branch of a spin-split surface-state band. The spin quantization axis is along the surface normal and inverts according to the time-reversal symmetry. Since this spin-split branch is the unique metallic band on this surface, the surface conductivity should be governed by this spin-split branch, suggesting a possible spin-polarized electric current.
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Affiliation(s)
- Y Ohtsubo
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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Ohtsubo Y, Delawary M, Kimbara K, Takagi M, Ohta A, Nagata Y. BphS, a key transcriptional regulator of bph genes involved in polychlorinated biphenyl/biphenyl degradation in Pseudomonas sp. KKS102. J Biol Chem 2001; 276:36146-54. [PMID: 11459836 DOI: 10.1074/jbc.m100302200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The bph genes in Pseudomonas sp. KKS102, which are involved in the degradation of polychlorinated biphenyl/biphenyl, are induced in the presence of biphenyl. In this study our goal was to understand the regulatory mechanisms involved in the inducible expression. The bph genes (bphEGF(orf4)A1A2A3BCD(orf1)A4R) constitute an operon, and its expression is strongly dependent on the pE promoter located upstream of the bphE gene. A bphS gene, whose deduced amino acid sequence showed homology with the GntR family transcriptional repressors, was identified at the upstream region of the bphE gene. Disruption of the bphS gene resulted in constitutive expression of bph genes, suggesting that the bphS gene product negatively regulated the pE promoter. The gel retardation and DNase footprinting analyses demonstrated specific binding of BphS to the pE promoter region and identified four BphS binding sites that were located within and immediately downstream of the -10 box of the pE promoter. The four binding sites were functional in repression because their respective elimination resulted in derepression of the pE promoter. The binding of BphS was abolished in the presence of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, an intermediate compound in the biphenyl degradation pathway. We concluded that the negative regulator BphS plays a central role in the regulation of bph gene expression through its action at the pE promoter.
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Affiliation(s)
- Y Ohtsubo
- Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
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Ohtsubo Y, Nagata Y, Kimbara K, Takagi M, Ohta A. Expression of the bph genes involved in biphenyl/PCB degradation in Pseudomonas sp. KKS102 induced by the biphenyl degradation intermediate, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid. Gene 2000; 256:223-8. [PMID: 11054551 DOI: 10.1016/s0378-1119(00)00349-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The bph genes involved in PCB/biphenyl degradation in Pseudomonas sp. KKS102 are clustered as bphEGFA1A2A3BCDA4R. The bph genes are inducibly expressed in the presence of biphenyl. In order to understand the induction more fully, the inducer of bph gene expression was investigated. To identify the inducer molecule, we constructed four deletion mutants of the structural genes and analyzed the inducibility of the bphE gene in each mutant strain. In the wild-type cell and the bphD deletion mutant, the levels of the bphE transcript were enhanced in the presence of biphenyl. On the other hand, in the bphA, bphB, and bphC deletion mutants, levels of the bphE transcript were not enhanced in the presence of biphenyl. These results demonstrated that the series of reactions catalyzed by biphenyl dioxygenase (BphA), dihydrodiol dehydrogenase (BphB), and 2, 3-dihydroxybiphenyl dioxygenase (BphC) are necessary to convert biphenyl to the inducer. It is known that these reactions convert biphenyl to 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA), and it was found that the expression of the bph genes was induced by purified HOPDA. These results clearly indicate that HOPDA is the inducer of the bph genes in KKS102.
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Affiliation(s)
- Y Ohtsubo
- Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, 113-8657, Tokyo, Japan
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Ohtsubo Y, Miyauchi K, Kanda K, Hatta T, Kiyohara H, Senda T, Nagata Y, Mitsui Y, Takagi M. PcpA, which is involved in the degradation of pentachlorophenol in Sphingomonas chlorophenolica ATCC39723, is a novel type of ring-cleavage dioxygenase. FEBS Lett 1999; 459:395-8. [PMID: 10526172 DOI: 10.1016/s0014-5793(99)01305-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The pentachlorophenol (PCP) mineralizing bacterium Sphingomonas chlorophenolica ATCC39723 degrades PCP via 2,6-dichlorohydroquinone (2,6-DCHQ). The pathway converting PCP to 2,6-DCHQ has been established previously; however, the pathway beyond 2,6-DCHQ is not clear, although it has been suggested that a PcpA plays a role in 2, 6-DCHQ conversion. In this study, PcpA expressed in Escherichia coli was purified to homogeneity and shown to have novel ring-cleavage dioxygenase activity in conjunction with hydroquinone derivatives, and converting 2,6-DCHQ to 2-chloromaleylacetate.
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Affiliation(s)
- Y Ohtsubo
- Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
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10
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Kiso T, Namikawa T, Tokunaga T, Sawada K, Kakita T, Shogaki T, Ohtsubo Y. Anti-obesity and anti-diabetic activities of a new beta3 adrenergic receptor agonist, (S)-(Z)-[4-[[1-[2-[(2-hydroxy-3-phenoxypropyl)]amino]ethyl]-1-propenyl] phenoxy] acetic acid ethanedioic acid (SWR-0342SA), in KK-Ay mice. Biol Pharm Bull 1999; 22:1073-8. [PMID: 10549858 DOI: 10.1248/bpb.22.1073] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We investigated the beta-adrenergic receptor (AR) agonistic activities in rats and humans, and the anti-obesity and anti-diabetic activities in KK-Ay mice, of a new beta3-AR agonist, SWR-0342SA ((S)-(Z)-[4-[[1-[2-[(2-hydroxy-3-phenoxypropyl)]amino]ethyl]-1-pro penyl]phenoxy] acetic acid ethanedioic acid). With regards to its beta-AR agonistic activity in rats, SWR-0342SA stimulated the atrial beating rate (beta1-AR activity) and white adipocyte lipolysis (beta3-AR activity), but did not induce uterine muscle relaxation (beta2-AR activity). The beta3-AR agonistic activity of SWR-0342SA was about 20 times stronger than its beta1-AR agonistic activity. Similarly, SWR-0342SA enhanced the accumulation of cAMP in Chinese hamster ovary (CHO) cells expressing human beta1- and beta3-ARs, while having no effect in CHO cells expressing beta2-ARs. Adenylyl cyclase stimulation by SWR-0342SA in CHO cells expressing beta3-ARs was about 35 times higher than that in CHO cells expressing beta1-ARs. With regards to anti-obesity and anti-diabetic activities, SWR-0342SA had no effect on body weight or food intake, but slightly decreased the fat pads weight in KK-Ay mice, an animal model of obesity and non-insulin-dependent diabetes mellitus (NIDDM). On the other hand, SWR-0342SA significantly decreased both blood glucose (to about 46% of control) and serum insulin levels (to about 40% of control) in KK-Ay mice. These results indicated that SWR-0342SA is a selective beta3-AR agonist, and possesses potent anti-diabetic activity, and that the anti-obesity activity is inferior to the anti-diabetic activity.
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Affiliation(s)
- T Kiso
- Research Department, Sawai Pharmaceutical Co., Ltd., Osaka, Japan
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Shuto T, Sekido K, Ohtsubo Y, Saida A, Yamamoto I. Dandy-Walker syndrome associated with occipital meningocele and spinal lipoma--case report. Neurol Med Chir (Tokyo) 1999; 39:544-7. [PMID: 10437385 DOI: 10.2176/nmc.39.544] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A neonate presented with Dandy-Walker syndrome associated with occipital meningocele and spinal lipoma, manifesting as soft masses on the skull and lumbosacral regions. Magnetic resonance imaging demonstrated a large posterior fossa cyst between the fourth ventricle and occipital meningocele, but the aqueduct was patent and there was no sign of hydrocephalus. A cyst-peritoneal shunt was emplaced at the age of 8 days followed by partial removal of the spinal lipoma and untethering of the cord at the 3 months. Follow-up examination of age 3 years found almost normal development, although the cyst still persisted.
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Affiliation(s)
- T Shuto
- Department of Neurosurgery, Kanagawa Children's Medical Center, Yokohama, Japan
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Tokunaga T, Kiso T, Namikawa T, Ohtsubo Y. cAMP-independent chloride secretion activated by a vasoactive intestinal peptide in a monolayer culture of human bronchial epithelial cells. Biol Pharm Bull 1999; 22:745-8. [PMID: 10443477 DOI: 10.1248/bpb.22.745] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the effects of vasoactive intestinal peptide (VIP) on Cl- transport across normal human bronchial epithelial (NHBE) cells grown in a monolayer, changes in short-circuit current (Isc) were measured in Ussing chamber systems. In the presence of 10(-4) M amiloride, the addition of VIP to the serosal solution led to an increase in the Isc in a concentration-dependent manner, the 50% effective concentration (EC50) being 2.6 x 10(-11) M. However, the addition of 10(-5) M forskolin had little effect on the increase in Isc. On the other hand, in the intracellular cAMP measurement, 10(-5) M forskolin remarkably increased the cAMP levels, but 10(-7) M VIP did not. This result suggests that Cl- secretion by VIP is not related to the raised intracellular cAMP levels in NHBE cells.
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Affiliation(s)
- T Tokunaga
- Research Department, Sawai Pharmaceutical Co., Ltd., Osaka, Japan
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Tokushima T, Utsunomiya T, Yoshida K, Ogawa T, Kido K, Ohtsubo Y, Ryu T, Ogata T, Tsuji S, Matsuo S. Estimation of the systolic pulmonary arterial pressure using contrast-enhanced continuous-wave Doppler in patients with trivial tricuspid regurgitation. Jpn Heart J 1999; 40:311-20. [PMID: 10506853 DOI: 10.1536/jhj.40.311] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Noninvasive estimation of pulmonary arterial pressure is important for hemodynamic monitoring of patients with heart disease. In patients with tricuspid regurgitation (TR), the peak velocity of TR on continuous-wave (CW) Doppler can be used to estimate the systolic pulmonary arterial pressure (PAPs) using the simplified Bernoulli equation. We evaluated a new technique of contrast-enhanced CW Doppler for calculating PAPs in patients with trivial TR. Forty-one patients without visible TR detected by color Doppler, pulsed Doppler or CW Doppler were evaluated. Age ranged from 19 to 73 (55 +/- 12) years old. Tricuspid flow signals were recorded on CW Doppler after intravenous administration of indocyanin green (ICG) or Albunex. PAPs was calculated as; PAPs = 4 x VTR2 + 10 mmHg, where VTR is the peak velocity of TR. PAPs calculated using contrast-enhanced CW Doppler was compared with PAPs measured by the following cardiac catheterization. 1) TR signals were recorded using the contrast-enhanced CW Doppler technique in 39 of 41 patients (95%) after intravenous administration of contrast agents. 2) The error of estimate of PAPs using the contrast-enhanced CW Doppler technique was -2.4 +/- 7.5 mmHg, and the percent error was -10.7 +/- 32.4% in all patients. In 20 of 39 patients (51%), the error of estimate was within +/- 5 mmHg. 3) PAPs was overestimated by 12.2 +/- 6.1 mmHg in patients with good contrast enhancement of TR signals. The contrast-enhanced CW Doppler technique is useful for estimating PAPs noninvasively in patients with trivial TR. It is better to assume the right atrial pressure as 3-5 mmHg, not 10 mmHg, in patients with good enhancement of trivial TR. Physiological TR may be enhanced by contrast agents in these patients.
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Affiliation(s)
- T Tokushima
- Department of Internal Medicine, Saga Medical School, Japan
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Sawabe A, Morita M, Kiso T, Kishine H, Ohtsubo Y, Ouchi S, Okamoto T. Structural analyses of a precursory substance of bitterness: new polyisoprenepolyols isolated from an edible mushroom (Hypsizigusmarmoreus) by fast atom bombardment mass spectrometry. J Agric Food Chem 1999; 47:588-593. [PMID: 10563937 DOI: 10.1021/jf980843y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
New polyisoprenepolyols (hypsiziprenol AA and BA) were isolated from an edible mushroom (Hypsizigus marmoreus). These polyols occur as a mixture of homologous polyisoprene derivatives with 40-70 carbon atoms. Analyses by FAB/MS in the positive and negative ion modes are complementary with each other in that the former provides information on the number of hydroxy groups present while the latter specifies the isoprenoid sequence, and thus become a powerful tool for analyzing the structures of polyisoprenepolyols. No polyisoprenepolyols obtained here were found to have antitumor activity on NCI-H292 and EL-4 cell lines.
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Affiliation(s)
- A Sawabe
- Institute for Comprehensive Agricultural Sciences and Faculty of Agriculture, Kinki University, Nara, Japan.
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Sawabe A, Morita M, Kiso T, Kishine H, Ohtsubo Y, Minematsu T, Matsubara Y, Okamoto T. Isolation and characterization of new limonoid glycosides from Citrus unshiu peels. Carbohydr Res 1999; 315:142-7. [PMID: 10385977 DOI: 10.1016/s0008-6215(98)00328-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Three limonoid glycosides were isolated from Citrus unshiu peels, and their structures were determined based on MS and NMR spectroscopic data as nomilinic acid 17-O-beta-D-glucopyranoside (1), methyl nomilinate 17-O-beta-D-glucopyranoside (2), and obacunone 17-O-beta-D-glucopyranoside (3). In particular, the location of the sugar moiety was clearly determined by the B/E constant linked scan FABMS method. No limonoid glycosides obtained here were found to have antitumor activity in NCI-H292 and EL-4 cell lines.
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Affiliation(s)
- A Sawabe
- Institute for Comprehensive Agricultural Sciences, Kinki University, Nara, Japan
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16
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Morishima Y, Tashiro T, Yamamori H, Takagi K, Ohtsubo Y, Sugiura T, Hayashi N, Furukawa K, Itabashi T, Sano W, Toyoda Y, Nitta H, Nakajima N. [Inoperable esophageal carcinoma managed by combined chemotherapy (CBDCA, 5-FU and VDS) and radiotherapy]. Gan To Kagaku Ryoho 1997; 24:965-9. [PMID: 9212805 DOI: pmid/9212805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Eleven inoperable patients with advanced esophageal carcinoma were treated with chemotherapy (carboplatin, 5-FU, vindesine) and concomitant radiotherapy. Two patients (T2) received this treatment due to their poor general condition and refusal of operation, and 9 patients for infiltration of tumor into the adjacent organs (T4). Administration of carboplatin (30 mg/body) and 5-FU (250 mg/body) together with radiotherapy (1.8 Gy/d) for 5 days a week was performed. This chemoradiation therapy was carried out for 5 consecutive weeks. In addition, vindesine (1-3 mg/body) was administered in the 1st and 4th week. After evaluation, endoscopic balloon dilatation was performed in 6 patients with stenosis of the esophagus. The general response rate was 80%. CR was noted in 2 patients of T2 but 1 patient of T4 developed severe leucopenia and immunosuppression, and died of septic MOF. All but the MOF case could take enough food orally following the endoscopic dilatation. The 1-year survival rate in the T4 group (45%) was significantly better than the non-treatment group (0%). In conclusion, this treatment is beneficial for patients with inoperable esophageal carcinoma to obtain a satisfactory QOL and survival rate.
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Affiliation(s)
- Y Morishima
- Dept. of Surgery I, School of Medicine, Chiba University
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17
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Tokunaga T, Oka K, Takemoto A, Ohtsubo Y, Gotoh N, Nishino T. Efficacy of trimethoprim in murine experimental infection with a thymidine kinase-deficient mutant of Escherichia coli. Antimicrob Agents Chemother 1997; 41:1042-5. [PMID: 9145866 PMCID: PMC163847 DOI: 10.1128/aac.41.5.1042] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The antimicrobial activity of trimethoprim is antagonized by thymidine in in vitro susceptibility tests. The purpose of this investigation was to determine whether this antagonism also occurred during experimental infection in mice, which have high serum thymidine concentrations. We derived a mutant strain of Escherichia coli, TT-48, incapable of utilizing exogenous thymidine from parent strain E. coli KC-14 and then investigated the in vitro and in vivo antimicrobial activities of trimethoprim, sulfamethoxazole, cefdinir, and ofloxacin against these strains. E. coli TT-48 lacked the activity of thymidine kinase, which catalyzes the conversion of thymidine to thymidylate, but its growth curve remained close to that of the parent strain. The MICs of all of the antimicrobial agents tested, except cefdinir, for the mutant strain were slightly inferior to those for the parent strain. The bactericidal effect of trimethoprim against the parent strain was antagonized by thymidine at concentrations of more than 1 microg/ml, while that against the mutant strain was not affected by thymidine even at the highest concentration (10 microg/ml). The therapeutic efficacy of trimethoprim in experimental murine infections was significantly higher when the mutant rather than the parent strain was used, whereas the therapeutic efficacy of cefdinir or ofloxacin, whose antimicrobial action is independent of folic acid synthesis, was the same with both strains. Unexpectedly, sulfamethoxazole also had similar efficacy against both strains. Thus, high thymidine concentrations antagonized the antimicrobial activity of trimethoprim in vitro and in vivo.
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Affiliation(s)
- T Tokunaga
- Department of Microbiology, Kyoto Pharmaceutical University, Yamashina-ku, Japan
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Kataoka H, Isoi T, Kiso T, Tanaka C, Shinkawa R, Kakita T, Shogaki T, Furukawa M, Ohtsubo Y. Pharmacological profiles of a new antiulcer agent, SWR-215. Biol Pharm Bull 1997; 20:28-35. [PMID: 9013802 DOI: 10.1248/bpb.20.28] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We investigated the effects of a new antiulcer agent, SWR-215 ([[(1,2-dihydro-2-oxo-4-quinolinyl)methyl]thio]-N-[[[4-(1-piperidinyl methyl)-2-pyridinyl]oxy]-Z-2-butenyl]acetamide), on histamine H2-receptors, gastric acid secretion and various acute experimental gastric lesions. SWR-215 showed unsurmountable histamine H2-antagonism on isolated guinea-pig atrium. In gastric secretion studies, SWR-215 exhibited potent and durable inhibitory effects, and the antisecretory activities were much stronger than that of roxatidine acetate hydrochloride (roxatidine): 5 times stronger on basal acid secretion in pylorus ligated rats, 11 times stronger on histamine-stimulated acid secretion in acute fistula rats, and 2 times stronger on histamine stimulated acid secretion in Heidenhain-pouch dogs, respectively. In various experimental acute gastric lesion studies, SWR-215 potentially inhibited almost all acute gastric and duodenal lesions compared with roxatidine, especially indomethacin-induced and HCl-ethanol-induced gastric lesions, and the inhibitory effects were exhibited at the same or lower doses than those which caused the antisecretory effect. Furthermore, it was considered that the mucosal protective effect of SWR-215 was probably unrelated to the endogenous prostaglandin system in gastric mucosa. These results suggest that SWR-215 possesses both durable antisecretory and mucosal protective effects, and is expected to be a useful drug for the treatment of patients with peptic ulcers.
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Affiliation(s)
- H Kataoka
- Research Department, Sawai Pharmaceutical Co., Ltd., Asahi-ku, Osaka, Japan
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19
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Abstract
This study addressed people's judgments about desirability of various reward allocation under different task-rules aggregating individual inputs to a group outcome. The rules used in the study were additive, conjunctive, and disjunctive (Steiner, 1972), and subjects evaluated twelve cases of reward allocation reflecting different distributive principles, such as equality and equity. It was found that no one principle was favored under all three aggregation rules. Generally, a distributive principle was favored that was most beneficial for the member whose input 'determined' group success. Specifically, equality was endorsed most often under the conjunctive rule, and equity under the disjunctive rule. It was also found that the Pareto axiom was frequently violated. In pairwise comparison, more than 60% of the subjects endorsed an allocation scheme, that was, subjectively fairer but objectively inferior in terms of Pareto optimality, revealing their commitment to a specific distributive principle. The results suggest that the universal economic assumption of Pareto optimality for social policy-making be seriously questioned.
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Affiliation(s)
- Y Ohtsubo
- Department of Behavioral Science, Faculty of Letters, Hokkaido University, Sapporo
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20
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Shinkawa R, Kiso T, Kataoka H, Isoi T, Kakita T, Shogaki T, Ohtsubo Y. [Effects of Cuban analog (SWR-104SA), a new histamine H2 receptor antagonist, on gastric acid secretion and experimental ulcer formation]. YAKUGAKU ZASSHI 1996; 116:783-91. [PMID: 8950870 DOI: 10.1248/yakushi1947.116.10_783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The antagonism of histamine H2-receptor by SWR-104SA (1'-bromo-N-[3-[3-(1-piperidinylmethyl) phenoxy] propyl]-spiro [1,3-dioxolane-2,9'-pentacyclo-[4.3.0.0.(2,5)0.(3,8) 0.(4,7)]nonane]-4'-carboxamide monooxalate) was estimated using the isolated guinea-pig atrium and gastric acid secretion in rats. The concentration-response curves for the positive chronotropic effect of histamine on the atrium were displaced to the right in parallel without change in the maximum response by SWR-104SA and roxatidine acetate hydrochloride (roxatidine). The pA2 values of SWA-104SA and roxatidine acetate hydrochloride were 7.27 and 7.38, respectively. The slopes of the regression line of log (DR-1) against log SWR-104SA and roxatidine concentration were 1.00 and 0.92, respectively. There was no significant difference between the two compounds with respect to the histamine H2-receptor antagonism and/or binding manner in vitro. In the rat gastric fistula model stimulated by histamine, however, antisecretory potency of SWR-104SA was 3 times less than that of roxatidine. SWR-104SA given p.o. prevented the formation of gastric lesion induced by HCl-ethanol and indomethacin dose-dependently, roxatidine also prevented its formation by HCl-ethanol, but failed to prevent that by indomethacine. These antiulcer activities of SWR-104SA were shown at the lesser doses of antisecretory activity. On the other hand, roxatidine did not prevent the ulcer formation at the same dose level of antisecretory activity. These results indicate that the antiulcer effect of SWR-104SA is not caused by the antisecretory action alone. In addition, the mucosal protective activity of SWR-104SA for HCl-ethanol induced gastric lesion was independent of endogenous prostaglandins. Moreover SWR-104SA had inhibitory effects on indomethacin-induced gastric hypermotility in rats. These actions may partly explain the gastric protection of this compound and additional mechanisms such as mucosal blood flow could be involved in the antiulcer efficacy. Consequently, it appears that SWR-104SA is a new antiulcer drug that exerts a potent cytoprotective effect in addition to its gastric antisecretory activity.
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Affiliation(s)
- R Shinkawa
- Research Department, Sawai Pharmaceutical Co. Ltd., Osaka, Japan
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21
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Tokushima T, Utsunomiya T, Ogawa T, Kido K, Ohtsubo Y, Ryu T, Yoshida K, Ogata T, Tsuji S, Matsuo S. Contrast-enhanced radiographic computed tomographic findings in patients with straight back syndrome. Am J Card Imaging 1996; 10:228-34. [PMID: 9012389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
UNLABELLED Straight back syndrome (SBS) is usually diagnosed by physical and chest radiographic findings. Radiographic computed tomographic (CT) findings are very useful for the diagnosis and the evaluation of its severity. The purpose is to evaluate the relationship between chest X-ray film and CT findings. SUBJECTS We evaluated 26 patients (SBS group) and 11 normal subjects (control group). SBS group consisted of 15 patients without structural heart disease (group I) and 11 patients with other heart disease (group II). METHODS (1) On the chest X-ray film, antero-posterior diameter (APD) of the thorax, transthoracic diameter (TTD), and APD/TTD ratio were measured. (2) On the CT image, three parameters were calculated; APD of the left atrium (LA diameter), APD/transverse diameter ratio of the heart (flattening ratio) and left side shift ratio of the heart (shifting ratio). (3) CT parameters were compared with APD/TTD ratio in patients and control group. RESULTS (1) APD/TTD ratio was smaller in group I and II than control group (30.0 +/- 5.4, 30.5 +/- 4.0 v 44.6 +/- 2.7%, p < .001). (2) LA diameter was smaller in group I and II than control group (23.2 +/- 4.1, 26.0 +/- 8.6 v 30.0 +/- 6.5 mm, p < .01). Flattening ratio was also smaller in group I and II than control group (59.2 +/- 9.4, 61.8 +/- 8.6 v 75.4 +/- 13.2%, p < .01). Shifting ratio was greater in group I and II than control group (10.9 +/- 5.0, 11.9 +/- 4.5 v 8.4 +/- 4.0%, p < .01). (3) APD/TTD ratio correlated with LA diameter (r = .39, p < .05) and flattening ratio (r = .53, p < .001). APD/TTD ratio did not correlate with shifting ratio (r = -.27, NS). CONCLUSIONS APD/TTD ratio correlated with LA diameter and flattening ratio rather than shifting ratio. LA diameter and flattening ratio on the CT image were more useful for evaluating the severity.
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Affiliation(s)
- T Tokushima
- Department of Internal Medicine, Saga Medical School, Japan
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Tokushima T, Utsunomiya T, Ogawa T, Kidoh K, Ohtsubo Y, Ryu T, Yoshida K, Ogata T, Tsuji S, Matsuo S. Short- and long-term effects of nisoldipine on cardiac function and exercise tolerance in patients with hypertrophic cardiomyopathy. Basic Res Cardiol 1996; 91:329-36. [PMID: 8874782 DOI: 10.1007/bf00789305] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 02/02/2023]
Abstract
UNLABELLED Nisoldipine is a second generation dihydropyridine calcium antagonist having characteristics of strong coronary artery dilating effect and less negative inotropic action. The purpose of this study was to evaluate the effect of nisoldipine on the cardiac function (systolic and diastolic) and the exercise tolerance, in patients with hypertrophic cardiomyopathy (HCM). SUBJECTS Twenty-three patients with HCM were studied. METHODS We measured the following indices using M-mode and pulsed wave Doppler echocardiography before and after nisoldipine therapy; left ventricular fractional shortening (LVFS), isometric relaxation time (IRT), deceleration half-time (DHT) of early diastolic mitral (E) flow, late diastolic mitral (A) flow and A/E ratio. Symptom-limited treadmill exercise test was performed. Exercise tolerance (EX) time was measured. Nisoldipine of 10 mg/day was orally administered. Same tests were repeated on day 14 and after 6 months. RESULTS 1) Short-term effects; LVFS did not change (55.9 +/- 5.9%-->57.0 +/- 7.4%, NS) after 2 weeks. However, LV diastolic function significantly improved (IRT; 92.1 +/- 7.7 ms-->85.2 +/- 11.6 ms, p < 0.05, DHT; 70.7 +/- 16.2 ms-->63.3 +/- 3.7 ms, p < 0.05). EX time increased (8.9 +/- 2.6 min-->10.0 +/- 3.3 min, p < 0.05), 2) Long-term effects; LV diastolic function had a tendency toward improvement, but is statistically not significant (IRT; 91.1 +/- 7.6-->83.8 +/- 11.6 ms, DHT; 73.1 +/- 23.4-->61.0 +/- 11.4 ms, A/E; 1.26 +/- 0.29-->1.11 +/- 0.36) after 6 months. EX time was significantly increased (9.4 +/- 1.7--> 10.1 +/- 1.7 min, p < 0.05). CONCLUSIONS Nisoldipine improved LV diastolic dysfunction and exercise tolerance in patients with HCM. These effects were similar to the first generation calcium antagonists. LV diastolic dysfunction may be improved due to the reduction of intracellular calcium concentration and the relief of myocardial ischemia by strong coronary artery dilating effect. However, nisoldipine did not affect the LV systolic function because of its less negative inotropic effect.
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Affiliation(s)
- T Tokushima
- Department of Internal Medicine Saga Medical School, Japan
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Abstract
We report the case of an infant with a cerebellar astrocytoma that showed marked calcification within only 6 months. In general, only slow-growing tumors tend to calcify. To our knowledge, no other case of such rapid calcification in cerebellar astrocytoma has been reported.
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Affiliation(s)
- T Shuto
- Department of Neurosurgery, Kanagawa Children's Medical Center, Yokohama, Japan
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24
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Matsuo S, Ogawa T, Ohtsubo Y. [Congenital and secondary long QT syndrome]. Ryoikibetsu Shokogun Shirizu 1996:203-7. [PMID: 9047443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- S Matsuo
- Department of Internal Medicine, Saga Medical School
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25
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Kikuchi Y, Nagata Y, Ohtsubo Y, Koana T, Takagi M. Pseudomonas fluorescens KKL101, a benzoic acid degrader in a mixed culture that degrades biphenyl and polychlorinated biphenyls. Biosci Biotechnol Biochem 1995; 59:2303-4. [PMID: 8611753 DOI: 10.1271/bbb.59.2303] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A mixed culture we had isolated, which degrades biphenyl/polychlorinated biphenyls, is composed of two strains, Pseudomonas fluorescens KKL101 and Pseudomonas sp. strain KKS102. KKS102 produces benzoic acid as a dead-end metabolite in the degradation of biphenyl. In this study we showed that KKL101 grew on benzoic acid as a sole source of carbon. This indicated a role of KKS102 in the growth of KKL101 and KKL101 for the growth of KKS102 in the mixed culture.
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Affiliation(s)
- Y Kikuchi
- Department of Biotechnology, University of Tokyo, Japan
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26
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Abstract
A case of choroid plexus papilloma of the III ventricle associated with hydrocephalus in an 1-month-old boy is reported. The tumor was removed after placement of a ventriculoperitoneal shunt; however, the histologically mainly benign tumor grew very rapidly. The cause of this rapid growth may have been a drop in the intraventricular pressure after the shunting procedure.
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Affiliation(s)
- T Shuto
- Department of Neurosurgery, Kanagawa Children's Medical Center, Yokohama, Japan
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27
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Terao T, Oga T, Nozaki S, Ohta A, Ohtsubo Y, Yamamoto S, Zamami M, Okada M. Lithium addition to neuroleptic treatment in chronic schizophrenia: a randomized, double-blind, placebo-controlled, cross-over study. Acta Psychiatr Scand 1995; 92:220-4. [PMID: 7484202 DOI: 10.1111/j.1600-0447.1995.tb09572.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [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: 01/25/2023]
Abstract
We studied the effect of lithium addition to neuroleptic treatment in chronic schizophrenia, for which contradictory results have been produced in previous studies. Twenty-one chronic schizophrenic inpatients received lithium in a study with randomized, double-blind, placebo-controlled, cross-over design consisting of 8 weeks each of treatment with lithium capsules and identical placebo capsules. The total Brief Psychiatric Rating Scale (BPRS) scores at week 8 of the lithium treatment were improved significantly compared with those at week 8 of the placebo treatment. Of the BPRS subscales, however, only anxiety-depression improved, whereas none of the subscales for anergia, thought disturbance, activation and hostile-suspiciousness improved. There was no significant difference between the total Scale for the Assessment of Negative Symptoms (SANS) scores at any time during lithium and placebo treatment. These results suggest that the addition of lithium to neuroleptic treatment improves anxiety-depression in chronic schizophrenia.
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Affiliation(s)
- T Terao
- Hitachi Umegaoka Mental Hospital, Japan
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28
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Fujita T, Nishikawa M, Ohtsubo Y, Ohno J, Takakura Y, Sezaki H, Hashida M. Control of in vivo fate of albumin derivatives utilizing combined chemical modification. J Drug Target 1994; 2:157-65. [PMID: 8069594 DOI: 10.3109/10611869409015905] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Three types of bovine serum albumin (BSA) derivatives such as lactosylated BSA (LBSA), mannosylated BSA (Man-BSA), and cationized BSA (cBSA) were synthesized and their hepatic disposition characteristics in mice were evaluated by pharmacokinetic analysis. At lower doses (< or = 1 mg/kg), LBSA and Man-BSA were very rapidly eliminated from the blood circulation due to uptake by parenchymal and nonparenchymal cells of the liver, respectively, via receptor-mediated endocytosis (Nishikawa et al., 1992; Nishida et al., 1991a, b). These uptake processes were nonlinear and the apparent hepatic uptake clearances (CLliver) were decreased at administered doses higher than 1 mg/kg, e.g. 10, 20, and 100 mg/kg. The liver accumulation of cBSA was also nonlinear, but its binding and/or uptake capacity in the liver was larger than those of LBSA and Man-BSA; i.e., CLliver decreased at doses higher than 20 mg/kg. In the next step, we modified these BSA derivatives by attaching polyethylene glycol (PEG), a modifier known to reduce the hepatic uptake and increase plasma retention, to achieve precise control of the in vivo disposition characteristics of BSA derivatives. By conjugation with PEG having a molecular weight of 10 kDa, the CLliver values of LBSA, Man-BSA, and cBSA were decreasing to one-seventh, one-fortyfifth, and one-onehundredthirtieth, respectively. However, liver accumulation of PEG modified LBSA and Man-BSA at 24 h after i.v. injection was not significantly different from unmodified BSA derivatives. These results suggest that it is possible to control the hepatic uptake of protein drugs by a combination of introduction of charge or sugar moieties and PEG conjugation.
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Affiliation(s)
- T Fujita
- Department of Basic Pharmaceutics, Faculty of Pharmaceutical Sciences, Kyoto University, Japan
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29
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Ohtsubo Y, Furukawa M, Imagawa T, Sugimoto N, Ikutoh M, Nakatsugi S, Katoh Y, Shinka S, Dohi Y. Growth inhibition of tumour cells by a liposome-encapsulated, mycolic acid-containing glycolipid, trehalose 2,3,6'-trimycolate. Immunology 1991; 74:497-503. [PMID: 1769697 PMCID: PMC1384646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In vivo growth of syngeneic tumour cells in the peritoneal cavity was strongly inhibited by intraperitoneal injection of a liposome-encapsulated, mycolic acid-containing glycolipid, trehalose 2,3,6'-trimycolate (TTM), derived from a non-pathogenic, acid-fast bacterium. Gordona aurantiaca. Peritoneal macrophages from mice after this treatment lysed tumour cells in vitro at a low effector/target ratio, and their culture supernatant inhibited tumour cell growth. The supernatant inhibited growth of not only tumour necrosis factor (TNF)-sensitive tumour cells, but also TNF-insensitive tumour cells. This inhibitory activity was enhanced by addition of lipopolysaccharide (LPS) to the culture medium of the macrophages. The macrophages released more superoxide (O2-), TNF and interleukin-1 (IL-1) on LPS triggering, and the releases of these compounds were further increased by addition of recombinant interferon-gamma (IFN-gamma) to the medium. Moreover, splenic T cells of TTM liposome-primed mice were found to produce eight times more IFN-gamma upon stimulation with LPS. These results indicated that priming with TTM liposomes resulted in strong activation of macrophages, which lysed tumour cells directly and also inhibited tumour cell growth by released factors.
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Affiliation(s)
- Y Ohtsubo
- Osaka Research Institute, Sawai Pharmaceutical Co., Ltd., Japan
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30
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Furukawa M, Ohtsubo Y, Sugimoto N, Katoh Y, Dohi Y. Induction of tumoricidal activated macrophages by a liposome-encapsulated glycolipid, trehalose 2,3,6'-trimycolate from Gordona aurantiaca. FEMS Microbiol Immunol 1990; 2:83-8. [PMID: 2257164 DOI: 10.1111/j.1574-6968.1990.tb03504.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A mycolic acid-containing glycolipid, trehalose 2,3,6'-trimycolate, prepared from a non-pathogenic acid-fast bacterium Gordona aurantiaca, was shown to induce strong tumoricidal activity in peritoneal exudate cells by intravenous or intraperitoneal injection of liposome-encapsulated preparations. The mycolic acid derivative containing a high proportion of unsaturated fatty acids rendered macrophages cytotoxic against syngeneic mastocytoma cells in the absence of endotoxin, for over 14 days after the injection. The macrophages were ascertained to be at low intracellular levels of a lysosomal enzyme beta-galactosidase and an ectoenzyme alkaline phosphodiesterase, a specific pattern as previously described for "primed macrophages". However the culture supernatants of the peritoneal exudate cells were not cytotoxic.
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Affiliation(s)
- M Furukawa
- Osaka Research Institute, Sawai Pharmaceutical Co., Japan
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31
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Fujita T, Sugimoto N, Yokoi F, Ohtsubo Y, Ikutoh M, Kato Y, Natsuhara Y, Oka S, Yano I. Induction of interferons (IFNs) and tumor necrosis factor (TNF) in mice by a novel glycolipid trehalose 2,3,6'-trimycolate from Rhodococcus aurantiacus (Gordona aurantiaca). Microbiol Immunol 1990; 34:523-32. [PMID: 1699114 DOI: 10.1111/j.1348-0421.1990.tb03169.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The immunomodifying activity of a novel mycoloyl glycolipid, trehalose 2,3,6'-trimycolate (GaGM), from a unique psychrophilic acid-fast bacterium, Rhodococcus aurantiacus, was examined. ICR mice were primed intravenously (i.v.) or intraperitoneally (i.p.) with liposomes containing GaGM (300 micrograms/mouse), and were administered LPS dissolved in saline (25 micrograms/mouse, i.v.) 2 weeks later. Two hours after injection of LPS, interferons (IFNs) and tumor necrosis factor (TNF) were induced significantly in mice sera. The increase in activities of IFNs and TNF was approximately paralleled with granuloma formation in spleen of mice primed with GaGM. However, IFNs and TNF were not induced either in mice primed with GaGM but not elicited with LPS, or in those primed with GaGM and elicited by GaGM. Both activities induced were lower in mice primed with trehalose mono- or dimycolate from R. aurantiacus (GaTMM, GaTDM) or TDM from Nocardia rubra than in GaGM-primed mice. Time course study showed that the maximum activity of each interferon (alpha, beta, or gamma) was observed at different stages after LPS administration; IFN-alpha, IFN-beta, and IFN-gamma appeared 3, 2, and 6 hours most abundantly after LPS administration, respectively.
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Affiliation(s)
- T Fujita
- Osaka Research Institute, Sawai Pharmaceutical Co., Ltd
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32
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Oda K, Nagayama N, Ohtsubo Y, Ohashi T, Hagihara R, Uomizu K, Yamashita W, Nakashima A, Harada R, Arima T. [Disturbance of the autonomic nerve system in patients with chronic renal failure--represented by variation coefficient of R-R intervals in the ECG as a parameter]. Fukuoka Igaku Zasshi 1990; 81:71-6. [PMID: 2328937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Autonomic nerve dysfunction in patients with chronic renal failure has of late become an issue to be investigated. R-R intervals in resting electrocardiograms were measured to evaluate activities of the cardiac parasympathetic nerve system. A total of 140 patients with chronic renal failure were studied to be compared with 20 normal controls (cont.) and 39 with diabetes mellitus (DM). Of these patients 15 were subjected to conservative treatment (CRF), while 125 patients were undergoing hemodialysis due to chronic renal failure-100 of them derived from chronic glomerulonephritis (HD) and 25 from diabetes mellitus (DM.HD). The variation coefficient of the R-R interval (CVRR) was measured after the subject patients had rested for over 15 minutes before a dialysis session. The mean CVRR were 2.15 +/- 1.25% in CRF group, 2.36 +/- 1.37% in HD and 1.37 +/- 0.99% in DM.HD. These values were significantly lower than in control group (4.70 +/- 2.64%). On the other hand, the value in DM.HD group, as shown above, was significantly lower than in HD. In CRF group the CVRR values lowered as residual renal functions decreased. No significant correlations between CVRR S and the duration of hemodialysis treatment were noted among the groups. In HD group the CVRR S were significantly lower in patients with hypotensive tendency during hemodialysis than in those who enjoyed good control of blood pressure. These results suggest that the measurement of CVRR S can be of help in evaluating autonomic nerve dysfunction in patients with chronic renal failure.
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Affiliation(s)
- K Oda
- Second Department of Internal Medicine, Faculty of Medicine, Kagoshima University
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Ohtsubo Y, Furukawa M, Sugimoto N, Ikutoh M, Katoh Y, Yano I, Shinka S, Dohi Y. [In vitro activation of immune cells by a mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate, derived from Gordona aurantiaca]. Nihon Saikingaku Zasshi 1989; 44:797-803. [PMID: 2533624 DOI: 10.3412/jsb.44.797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate (GaGM), derived from Gordona aurantiaca, an acid-fast bacteria closely related taxonomically to Mycobacterium, was investigated for its immune adjuvant activity in vitro. The liposomes containing GaGM showed strong mitogenic effects on murine spleen cells at the doses used (25-100 micrograms/ml), but not on T-cell-depleted spleen cells or macrophage-depleted spleen cells. These results suggest that the mitogenic property of liposomes containing GaGM differs from that of such as lipopolysaccharide, a B-cell mitogen and that its mitogenic effects depend on the presence of macrophages. In addition, liposomes containing GaGM augmented the mixed lymphocyte reaction (MLR) and in vitro induction of cytotoxic T-lymphocytes (CTLs) against allogeneic tumor cells. These results suggest that liposomes containing GaGM have immune adjuvant properties in vitro and the adjuvant activity may be related to such cytokines as interleukin-1 and -2.
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Ohtsubo Y, Furukawa M, Fujinobu Y, Sugimoto N, Ikutoh M, Katoh Y, Yano I, Higasa M, Shinka S, Dohi Y. [An immune adjuvant activity of mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate, derived from Gordona aurantiaca]. Nihon Saikingaku Zasshi 1989; 44:533-9. [PMID: 2788754 DOI: 10.3412/jsb.44.533] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A mycolic acid-containing glycolipid, trehalose-2,3,6'-trimycolate (GaGM), derived from Gordona aurantiaca, an acid-fast bacterium closely related taxonomically to Mycobacterium, was investigated for its immune adjuvant activity on cell-mediated responses in the mouse. I.V. injection of liposomes containing GaGM enhanced the generation of cytotoxic T-lymphocyte (CTL) against syngeneic and allogeneic tumor cells. In addition, the injection of GaGM augmented the natural killer (NK) activity and the antibody-dependent cellular cytotoxicity (ADCC). These results suggest that the injection of GaGM induces the production of interleukin-2 (IL-2), since such effector cells as CTL, NK and K cells have been shown to require IL-2 for their development.
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Urakawa T, Hori K, Matsunaga Y, Naito S, Ohtsubo Y, Takase N, Kawai S, Hatta S, Nishimura K, Saitoh Y. [Experimental studies on mechanism of formation and prevention of cimetidine and vagotomy in stress ulcer (author's transl)]. Nihon Shokakibyo Gakkai Zasshi 1981; 78:1370-9. [PMID: 7311081] [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: 01/24/2023]
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Ohtsubo Y, Okada Y, Kameyama Y, Matsui K, Hamachi R. [Multiple myeloma (author's transl)]. Aichi Gakuin Daigaku Shigakkai Shi 1977; 15:310-5. [PMID: 281159] [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: 12/14/2022]
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