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991.
M Lin M Mendoza L Kane J Weinstein KM Sakamoto 《Canadian Metallurgical Quarterly》1998,26(10):1000-1006
p55Cdc, a cell cycle protein is expressed in cycling mammalian cells and is required for normal cell division. Expression of this protein is regulated during the cell cycle, peaking in late G1 and S. We have previously shown that constitutive expression of p55Cdc results in inhibition of granulocyte differentiation. Degradation of p55Cdc is also required for apoptosis in growth factor and serum starved cells. In the present study we prepared stably transfected cells conditionally expressing p55Cdc in response to zinc stimulation to investigate the role of inducible p55Cdc expression in apoptosis of myeloid cells. We report that inducible expression of p55Cdc in the myeloid leukemic cell line 32Dc13 resulted in increased cell death. p55Cdc overexpression led to a statistically significant decrease in the viability of 32Dc13 cells compared with that of control cells. Furthermore, cell staining and flow cytometry analysis revealed that p55Cdc-overexpressing 32Dc13 cells progressed to apoptosis much earlier than uninduced cells. These results suggest that inducible expression of p55Cdc leads to earlier increases in cell death in the absence of growth factor and serum in myeloid leukemic cells. 相似文献
992.
Hiroki Shibata Kan Sakamoto Atsushi Ouchi Masaki Kurata 《Journal of Nuclear Science and Technology》2015,52(10):1313-1317
Chemical reactions between stainless steel and boron carbide were investigated using the materials applied for control rods in BWRs in Japan, specifically 304L-type stainless steel and granular boron carbide. The reaction region consisted of 2–4 layers, in which the significant composition variation of each element was detected, especially for B and C. Assuming that the reaction layer growth obeys the parabolic law, the effective rate constant between 304L-type stainless steel and granular boron carbide was evaluated to be approximately one order of magnitude smaller than the previously reported values for boron carbide pellets or powers. This difference might originate from the loose contact between the stainless steel and the granular boron carbide in the present study. Regarding liquefaction progress, the stainless steel components were selectively dissolved in the melt; consequently, the unreacted boron carbide tended to remain. 相似文献
993.
Tohru Yamazaki Makiko Kadokura Yuki Mutoh Takeshi Sakamoto Mari Okazaki Atsushi Mitsumoto Yoichi Kawashima Naomi Kudo 《Lipids》2014,49(12):1203-1214
Fibrates have been reported to elevate the hepatic proportion of oleic acid (18:1n‐9) through inducing stearoyl‐CoA desaturase (SCD). Despite abundant studies on the regulation of SCD in the liver, little is known about this issue in the small intestine. The present study aimed to investigate the effect of clofibric acid on the fatty acid profile, particularly monounsaturated fatty acids (MUFA), and the SCD expression in intestinal mucosa. Treatment of rats with a diet containing 0.5 % (w/w) clofibric acid for 7 days changed the MUFA profile of total lipids in intestinal mucosa; the proportion of 18:1n‐9 was significantly increased, whereas those of palmitoleic (16:1n‐7) and cis‐vaccenic (18:1n‐7) acids were not changed. Upon the treatment with clofibric acid, SCD was induced and the gene expression of SCD1, SCD2, and fatty acid elongase (Elovl) 6 was up‐regulated, but that of Elovl5 was unaffected. Fat‐free diet feeding for 28 days increased the proportions of 16:1n‐7 and 18:1n‐7, but did not effectively change that of 18:1n‐9, in intestinal mucosa. Fat‐free diet feeding up‐regulated the gene expression of SCD1, but not that of SCD2, Elovl6, or Elovl5. These results indicate that intestinal mucosa significantly changes its MUFA profile in response to challenges by clofibric acid and a fat‐free diet and suggest that up‐regulation of the gene expression of SCD along with Elovl6 is indispensable to elevate the proportion of 18:1n‐9 in intestinal mucosa. 相似文献
994.
Naoki Sasaki Hsiang‐Ting Chen Daisuke Sakamoto Takeo Igarashi 《Computer Animation and Virtual Worlds》2015,26(2):185-194
We present facetons, geometric modeling primitives designed for building architectural models especially effective for a virtual environment where six degrees of freedom input devices are available. A faceton is an oriented point floating in the air and defines a plane of infinite extent passing through the point. The polygonal mesh model is constructed by taking the intersection of the planes associated with the facetons. With the simple interaction of faceton, users can easily create 3D architecture models. The faceton primitive and its interaction reduce the overhead associated with standard polygonal mesh modeling, where users have to manually specify vertexes and edges which could be far away. The faceton representation is inspired by the research on boundary representations (B‐rep) and constructive solid geometry, but it is driven by a novel adaptive bounding algorithm and is specifically designed for 3D modeling activities in an immersive virtual environment. We describe the modeling method and our current implementation. The implementation is still experimental but shows potential as a viable alternative to traditional modeling methods. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
J. A. Malmonge M. A. Dos Santos L. F. Malmonge D. H. F. Kanda G. O. Chierice W. K. Sakamoto 《应用聚合物科学杂志》2005,98(2):746-749
Molecular mobility in castor oil based polyurethane was investigated with thermally stimulated depolarization current (TSDC) measurements and alternating‐current (ac) dielectric relaxation spectroscopy. Three peaks could be observed in TSDC thermograms from 173 to 373 K. The relaxation located at 213 K could be attributed to the change in the molecular chain due to the interaction between the isocyanate and the solvent, and it was well fitted with the Vogel–Fulcher–Tammann equation. The other two peaks were located at 274 and 365 K and could be attributed to interfacial polarization and space charge, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 746–749, 2005 相似文献
996.
H Miyoshi K Takegami K Sakamoto T Mogi H Iwamura 《Canadian Metallurgical Quarterly》1999,125(1):138-142
Krabbe disease or globoid cell leukodystrophy (GLD) is an autosomal recessive disorder resulting from the defective lysosomal hydrolysis of specific galactolipids found primarily in myelin. This leads to severe neurological symptoms including seizures, hypotonia, blindness, and death, usually before 2 years of age in human patients. In addition to human patients, several animals, including dog, mouse, and monkey, have the same disease caused by a deficiency of galactocerebrosidase (GALC) activity. In this article we describe studies in cairn and West Highland white terriers (WHWT) affected with GLD. Through a screening test based on the molecular defect found in these breeds, over 50 cairn terrier carriers have been identified and a colony of five carrier dogs has been established. Affected dogs from this colony plus an affected WHWT were available for study. An affected WHWT was evaluated by magnetic resonance imaging at 6 and 11 months of age and pronounced changes in the T-2 weighted fast spin-echo images were found. Biochemical and pathological evaluation of the same dog after euthanasia at 12 months of age showed a large accumulation of psychosine in the brain and white matter filled with globoid cells. Some comparisons were made to younger affected and carrier dogs. Studies have shown successful transduction of cultured skin fibroblasts from an affected dog and normal canine bone marrow using a retroviral vector containing the human GALC cDNA. Successful treatment of this canine model will lead to studies in some humans with GLD. 相似文献
997.
Ricardo H. R. Castro Paulo J. B. Marcos Eduardo K. Sakamoto Douglas Gouvêa 《Journal of Materials Science》2007,42(16):6946-6950
Electrophoretic deposition (EPD) is a precision technique useful for obtaining high quality ceramic bodies with controlled
dimensions and smooth coatings. The electrophoretic deposition rate is highly dependent on the surface chemistry of the powders,
especially when dealing with multi-component systems. The objective of this work is to study the surface reactivity of both
ZrO2 and MgO in ethanol suspension to provide experimental benchmarks to control EPD of a ZrO2–3 wt% MgO mechanical mixture (Z3M) in ethanol. Infrared spectroscopy (FTIR) showed that ZrO2 surface spontaneously reacts with ethanol, generating negative electrophoretic mobility of the particles (−0.07 × 10−8 V−1 s−1) measured by Electroacoustic Sonic Amplitude (ESA). MgO surface also spontaneously reacted with ethanol, but a positive electrophoretic
mobility was observed in this case (0.26 × 10−8 V−1 s−1). Scanning Electron Microscopy of Z3M dried from ethanol suspension showed that MgO particles were located around the ZrO2 particles, forming composite agglomerates, probably due to the electrostatic attraction between MgO and ZrO2 particles. Homogeneous deposits could be obtained from EPD of Z3M ethanol suspensions. Mercury intrusion porosimetry showed
that the ZrO2–MgO green deposited bodies using different voltages had similar pores diameters distributions, indicating that the ZrO2–MgO agglomerates are not affected by the increasing deposition rates. 相似文献
998.
Kazuya Sakamoto Yoshinori Takashima Hiroyasu Yamaguchi Akira Harada 《Synthetic Metals》2009,159(9-10):977-981
2T-βCD2 and 3T-βCD2, which have bithiophene (2T) and terthiophene (3T) with β-cyclodextrin (CD) at each end form supramolecular assemblies in aqueous solutions. These supramolecular assemblies were characterized by NMR, UV, fluorescence spectroscopy, circular dichroism spectroscopy, and atomic force microscope (AFM). Supramolecular assemblies from 3T-βCD2 form orientated structures due to their π–π stacking ability. AFM images of the supramolecular assembly incorporating 3T-βCD2 showed fibrous objects on mica substrates. 相似文献
999.
The study of a disease using genetic identification has become possible by using haplotype information. The expectation-maximization
algorithms are the standard approach in haplotype analysis. These approaches maximize the likelihood function of a genotypic
distribution assuming Hardy-Weinberg equilibrium. However, these methods are time-consuming when applied to the sequence of
many loci. In this study, we used a genetic algorithm to obtain the haplotype frequencies from the frequencies of genotypes.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
1000.
N Matsunaga K Hayashi I Sakamoto Y Ogawa Y Matsuoka T Imamura T Kuriya 《Canadian Metallurgical Quarterly》1993,186(3):877-882
Coronary-to-pulmonary artery shunts via the bronchial artery (CA-BA-PA shunts) were observed in 16 of 2,922 consecutive patients who underwent selective coronary cineangiography. Underlying diseases included Takayasu arteritis (n = 8), chronic pulmonary inflammatory diseases (n = 4), pulmonary thromboembolism (n = 2), pulmonary artery tumor (n = 1), and tetralogy of Fallot with pulmonary atresia (n = 1). Ventilation-perfusion scans were available in 15 of the 16 patients. Mismatched defects were identified in 11 patients, and matched defects were identified in four. Bronchial-to-pulmonary artery shunts were detected on selective bronchial angiograms and/or thoracic aortograms in 13 patients. Feeding arteries of the CA-BA-PA shunts included left atrial branches (n = 13), right sinus node branches (n = 7), left sinus node branches (n = 2), right conal branch (n = 1), left conal branch (n = 1), and posterolateral branches (n = 2). These coronary branches seemed to serve as collateral vessels from a coronary arterial system with a higher pressure to a pulmonary arterial system with a lower pressure in conditions of decreased pulmonary flow or in cases of chronic pulmonary inflammatory disease. The importance of the coronary artery along with other superior thoracic collateral networks in contributing to the development of shunts to the pulmonary artery is underscored. 相似文献