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91.
Kanayama N Fukushima S Nishiyama N Itaka K Jang WD Miyata K Yamasaki Y Chung UI Kataoka K 《ChemMedChem》2006,1(4):439-444
Nonviral gene vectors from synthetic catiomers (polyplexes) are a promising alternative to viral vectors. In particular, many recent efforts have been devoted to the construction of biocompatible polyplexes for in vivo nonviral gene therapy. A promising approach in this regard is the use of poly(ethylene glycol) (PEG)-based block catiomers, which form a nanoscaled core-shell polyplex with biocompatible PEG palisades. In this study, a series of PEG-based block catiomers with different amine functionalities were newly prepared by a simple and affordable synthetic procedure based on an aminolysis reaction, and their utility as gene carriers was investigated. This study revealed that the block catiomers carrying the ethylenediamine unit at the side chain are capable of efficient and less toxic transfection even toward primary cells, highlighting critical structural factors of the cationic units in the construction of polyplex-type gene vectors. Moreover, the availability of the polyplex micelle for transfection with primary osteoblasts will facilitate its use for bone regeneration in vivo mediated by nonviral gene transfection. 相似文献
92.
Motoyuki Iijima Nobuhiro Sato Mayumi Tsukada Hidehiro Kamiya 《Journal of the American Ceramic Society》2007,90(9):2741-2746
The effects of the polycarboxylic dispersant structures on the crystallinity and sedimentation behavior of prepared BaTiO3 nanoparticles were analyzed using four types of dispersants—ethylenediaminetetraacetic acid dipotassium salt (EDTA), trans -aconitic acid (TAA), ammonium acrylate–methyl acrylate co-polymer (PAA50), and sodium polyacrylate (PAA100). In the case of EDTA and TAA, the adsorbed ratio of the dispersants on BaTiO3 nanoparticles was relatively low, and only slight improvement of sedimentation behavior was observed. On the other hand, in the case of PAA50 and PAA100, the adsorbed ratio was high, and the sedimentation behavior was gratefully improved. Next, in order to analyze the relationships among the additive amount of polycarboxylic dispersants, crystallinity, and sedimentation behavior, various amounts of PAA100 or PAA50 were treated in the synthesis solution. The sedimentation behavior of BaTiO3 nanoparticles improved with increasing amounts of PAA100 and PAA50 while their crystal phase became amorphous. Adding PAA50 at a molar ratio of COO− /Ba2+ =0.266 resulted in BaTiO3 nanoparticles with the best dispersion stability in an aqueous media. 相似文献
93.
Nobuhiro Moteki Nobuyuki Takegawa Kazuhiro Koizumi Takayuki Nakamura Yutaka Kondo 《Aerosol science and technology》2013,47(10):1184-1198
The generalized Kirchhoff's law predicts that the polarization state of thermal emission from an individual small particle depends on the particle shape. We show for the first time experimental evidence confirming this prediction for particles smaller than the wavelength by using a newly developed laser-induced incandescence instrument and a theoretical model that can predict the signals of thermal emission and light scattering for an ellipsoid under the dipole approximation (Rayleigh ellipsoid). We use single-sphere (singlet) and two-sphere clusters (doublet) of polystyrene latex spheres as primary test particles. These are currently available, well-characterized spherical and nonspherical particles, respectively. The polarization states of thermal emission and scattered light of graphite particles smaller than the wavelength show a good agreement with model calculations for plate-like Rayleigh-spheroids, consistent with their plate-like shapes observed by a transmission electron microscope. We propose that the measurement of the polarization state of thermal emission may be applicable to real-time analysis of the shape of light-absorbing particles in air. 相似文献
94.
Dietary conjugated linoleic acid reciprocally modifies ketogenesis and lipid secretion by the rat liver 总被引:3,自引:0,他引:3
Sakono M Miyanaga F Kawahara S Yamauchi K Fukuda N Watanabe K Iwata T Sugano M 《Lipids》1999,34(9):997-1000
The effects of dietary conjugated linoleic acid (CLA) and linoleic acid (LA) on ketone body production and lipid secretion
were compared in isolated perfused rat liver. After feeding the 1% CLA diet for 2 wk, the concentration of post-perfused liver
cholesterol was significantly reduced by CLA feeding, whereas that of triacylglycerol remained unchanged. Livers from CLA-fed
rats produced significantly more ketone bodies; and the ratio of β-hydroxybutyrate to acetoacetate, an index of mitochondrial
redox potential, tended to be consistently higher in the liver perfusate. Conversely, cumulative secretions of triacylglycerol
and cholesterol were consistently lower in the livers of rats fed CLA, and the reduction in the latter was statistically significant.
Thus dietary CLA appeared to exert its hypolipidemic effect at least in part through an enhanced β-oxidation of fatty acids
at the expense of esterification of fatty acid in the liver. 相似文献
95.
A direct nanoflow liquid chromatography-tandem mass spectrometry system for interaction proteomics 总被引:11,自引:0,他引:11
Natsume T Yamauchi Y Nakayama H Shinkawa T Yanagida M Takahashi N Isobe T 《Analytical chemistry》2002,74(18):4725-4733
One of the strategies of functional proteomics, research aiming to discover gene function at the protein level, is the comprehensive analysis of protein-protein interactions related to the functional linkage among proteins and analysis of functional cellular machinery to better understand the basis of cell functions. Here, we describe the direct nanoflow LC (DNLC) system, which is equipped with a fritless high-resolution electrospray interface column packed with 1-microm reversed-phase (RP) beads and a novel splitless nanoflow gradient elution system to operate the column. Using RP-DNLC at an extremely slow flow rate, <50 nL/min, combined with data-dependent collision-induced dissociation tandem MS (MS/MS) and computer-assisted retrieval of spectra, we identified approximately 100 protein components in a biological complex such as a premature mammalian ribosome pull-down from cultured cells when we used an epitope-tagged protein as bait. Because this analysis is most sensitive, requires approximately 0.2 microg of total protein, and is a fully automated 1-h process, we anticipated that it should be an excellent tool for analyzing a limited amount of functional multi-protein complexes in cells. 相似文献
96.
An optical levitation and translation method for a microscopic particle by use of the resultant force induced by multiple light beams is studied. We show dependence of the radiation pressure force on the illuminating distribution by numerical calculation, and we find that the strongest axial force is obtained by a specific spacing period of illuminating beams. Extending the optical manipulation technique by means of vertical-cavity surface-emitting laser (VCSEL) array sources [Appl. Opt. 40, 5430 (2001)], we are the first, to our knowledge, to demonstrate levitation of a particle and its translation while levitated by using a VCSEL array. The vertical position of the target particle can be controlled in a range of a few tens of micrometers with an accuracy of 2 microm or less. The analytical and experimental results suggest that use of multiple beams is an effective method to levitate a particle with low total illumination power. Some issues on the manipulation method that uses multiple beams are discussed. 相似文献
97.
Yoshihiro Kamada Hideki Fujii Hironobu Fujii Yoshiyuki Sawai Yoshinori Doi Naofumi Uozumi Kayo Mizutani Maaya Akita Motoya Sato Sachiho Kida Noriaki Kinoshita Nobuhiro Maruyama Takayuki Yakushijin Masanori Miyazaki Hisao Ezaki Naoki Hiramatsu Yuichi Yoshida Shinichi Kiso Yasuharu Imai Norifumi Kawada Tetsuo Takehara Eiji Miyoshi 《Proteomics. Clinical applications》2013,7(9-10):648-656
98.
Masashi Inoue Mitsunori Ogihara Ryoko Hanada Nobuhiro Furuyama 《Multimedia Tools and Applications》2012,61(1):7-20
The automated annotation of conversational video by semantic miscommunication labels is a challenging topic. Although miscommunications are often obvious to the speakers as well as the observers, it is difficult for machines to detect them from the low-level features. We investigate the utility of gestural cues in this paper among various non-verbal features. Compared with gesture recognition tasks in human-computer interaction, this process is difficult due to the lack of understanding on which cues contribute to miscommunications and the implicitness of gestures. Nine simple gestural features are taken from gesture data, and both simple and complex classifiers are constructed using machine learning. The experimental results suggest that there is no single gestural feature that can predict or explain the occurrence of semantic miscommunication in our setting. 相似文献
99.
Kaori?FujinamiEmail author Nobuhiro?Inagawa Kosuke?Nishijo Akifumi?Sokan 《Multimedia Tools and Applications》2012,57(2):269-293
In this article, we propose a middleware that supports a developer to build tabletop information display systems. We focus
on an application that projects information close to a particular object on a table. To let a user focus on his/her primary
task, the information is presented based on a current phase in a procedure, which we call procedure-awareness. Here, a current
phase is recognized through the utilization of objects. The proposed middleware separates information from acquisition and
presentation mechanisms: sensors for operational context recognition, sensors for object identification/tracking for “nearby
presentation”, and projecting information near an object. A developer just needs to write a set of rules, i.e. application
logic, that represent contents for particular operational contexts. Also, by implementing appropriate handlers, any content
can be provided. We present the design and the implementation of the middleware and validate the expressiveness of application
logics through prototype development. 相似文献
100.
Effect of initial grain size on the joint properties of friction stir welded aluminum 总被引:1,自引:0,他引:1
Yufeng Sun Hidetoshi Fujii Yutaka Takada Nobuhiro Tsuji Kazuhiro Nakata Kiyoshi Nogi 《Materials Science and Engineering: A》2009,527(1-2):317-321
In this study, 2 mm-thick commercial 1050-Al plates with an ultrafine grained (UFG) structure were obtained by the accumulative roll bonding (ARB) technique after a 5 cycle process and were subsequently joined by friction stir welding (FSW) at various revolution pitches (welding speed/rotation speed) of 1 mm/r, 1.67 mm/r and 2.5 mm/r. To understand the effect of the initial grain size on the welding properties, ARB processed samples followed by annealing under H24 conditions as well as the as-received samples in the fully annealed state were also applied to the FSW process. The microstructure evolution and Vickers hardness in the stir zone of all the samples were investigated. It was revealed that the annealed samples with an intermediate grain size finally obtained the most refined grain size and highest value of Vickers hardness in the stir zone. However, for the UFG samples, significant grain growth and corresponding decrease in hardness can be found in the stir zone. 相似文献