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61.
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63.
Koji Hashimoto Keiko Miwa Masanori Goto Yoshio Ishimori 《Supramolecular chemistry》2013,25(4):265-270
Abstract The authors have developed a novel, rapid, convenient, and specific gene detection method, named the ‘DNA sensor,’ using a graphite electrode loaded with DNA probes. Synthesized oligonucleotide (5-TGCAGTTCCGGTGGCTGATC-3′) complementary to oncogene v-myc was employed for a model probe. The oligonucleotide was chemically adsorbed on a basal plane pyrolytic graphite (BPPG) electrode. The sensor was able to be applied to a hybridization reaction (40°C) in a linearized pVM623 solution carrying the Pst I fragment of v-myc (1.5 kbp). After the hybridization reaction, the sensor was immersed into an acridine orange solution (1 μM) and washed with a phosphate buffer (pH 7.0). Acridine orange intercalated between base pairs of the formed double stranded DNAs on the electrode. The anodic peak potential of acridine orange that interacted with the DNAs on the electrode was measured. The positive shift of the peak potential increased in proportional to the pVM623 concentration in the hybridization reaction. 10?1 g/ml of pVM623 was able to be detected in the buffer solution using the sensor. This gene detection was completed within an hour. 相似文献
64.
Experimental detection of proteolytic activity in a signal peptide peptidase of Arabidopsis thaliana
Hoshi Masako Ohki Yu Ito Keisuke Tomita Taisuke Iwatsubo Takeshi Ishimaru Yoshiro Abe Keiko Asakura Tomiko 《BMC biochemistry》2013,14(1):1-8
Background
The ubiquitin ligase COP1, COnstitutively Photomorphogenic 1, functions in many biological responses in mammalian cells, but its downstream pathway remains unclear.Results
Here, we identified FIP200, a key regulator of mammalian autophagy, as a novel COP1-interacting protein by yeast two-hybrid screening. The interaction was confirmed by a GST-pulldown assay. Split-GFP analysis revealed that interaction between COP1 and FIP200 predominantly occurred in the cytoplasm and was enhanced in cells treated with UV irradiation. Different forms of FIP200 protein were expressed in cultured mammalian cells, and ectopic expression of COP1 reduced one of such forms.Conclusions
These data suggest that COP1 modulates FIP200-associated activities, which may contribute to a variety of cellular functions that COP1 is involved in. 相似文献65.
Reductive dehalogenation of aryl halides was achieved using hydrogen and a palladium catalyst. By using deuterium gas, the deuterated arenes were readily prepared. 相似文献
66.
Masaru Asari Kumiko Oka Tomohiro Omura Chikatoshi Maseda Yoshikazu Tasaki Hiroshi Shiono Kazuo Matsubara Mitsuyoshi Matsuda Keiko Shimizu 《Electrophoresis》2013,34(3):448-455
Amplification/hybridization‐based genetic analyses using primers containing locked nucleic acids (LNAs) present many benefits. Here, we developed a novel design for universal fluorescent PCR using LNAs. Universal fluorescent PCR generates intermediate nonlabeled fragments and final fluorescent fragments in a two‐step amplification process that uses locus‐specific primers with universal tails and universal fluorescent primers. In this study, a few standard nucleotides were replaced with LNAs only in the fluorescent universal primers. The sequence of the fluorescent universal primer significantly affected the amplification efficiency. For primers with three LNAs, the fluorescent primers with stable M13(‐47) sequences provided the most efficient signal (approximately tenfold higher than the primers with M13(‐21) sequences at lower Tm values). Moreover, AT‐rich LNA substitutions in the fluorescent primers produced much lower amplification efficiencies than GC‐rich substitutions. GC‐rich LNAs produced greater differences in Tm values among primers, and resulted in the preferential production of fluorescently labeled amplicons. The specificity and sensitivity of LNA‐containing fluorescent primers were assessed by genotyping eight STRs in Japanese individuals, and full STR profiles could be generated using as little as 0.25 ng of genomic DNA. The method permitted clear discrimination of alleles and represents sensitive STR genotyping at a reduced cost. 相似文献
67.
Kiyofumi Katagiri Keiko Ohta Kunihito Koumoto Kei Kurosu Yoshihiro Sasaki Kazunari Akiyoshi 《Colloid and polymer science》2013,291(6):1375-1380
Novel organic–inorganic hybrid nanoparticles consisting of polymer–hydrogel nanoparticles (nanogels) and iron oxide were developed for potential biomedical applications. Hybrid nanoparticles were prepared by a simple procedure using polysaccharide nanogels as a reactive site for iron oxide formation. The hybrid nanoparticles have a narrow size distribution with a diameter of approximately 30 nm and show high colloidal stability. These nanohybrid particles could be used as a contrast medium for magnetic resonance imaging or for magnetic hyperthermia therapy. 相似文献
68.
Tomohiro Sakata Shingo Ogawa Keiko Inoue Yumiko Shimizu Yusaku Tanahashi 《Surface and interface analysis : SIA》2022,54(6):661-666
To systematically evaluate the quality of SiNx films in multi-stacked structures, we investigated the effects of post-deposition annealing (PDA) on the film properties of SiNx within the SiO2/SiNx/SiO2/Si stacked structure by performing X-ray photoelectron spectroscopy (XPS), X-ray reflectivity (XRR), Fourier transform infrared (FT-IR) spectroscopy, and scanning transmission electron microscope–electron energy loss spectroscopy (STEM-EELS) analyses. The XPS results showed that PDA induces the oxidation of the SiNx layer. In particular, new finding is that Si-rich SiNx in the SiNx layer is preferentially oxidized by PDA even in multi-stacked structure. The XRR results showed that the SiNx layer becomes thinner, whereas the interface layer between the SiNx layer and Si becomes thicker. It is concluded by STEM-EELS and XPS that this interface layer is SiON layer. The density of N–H and Si–H bonding within the stacked structure strongly depends on the PDA temperature. Our study helps elucidate the properties of SiNx films in stacked structures from various perspectives. 相似文献
69.
Naoyoshi Komatsu Keiko Masumoto Hidemitsu Aoki Chiharu Kimura Takashi Sugino 《Applied Surface Science》2010,256(6):1803-8310
Synthesis of Si-added aluminum oxide (AlSiO) films is attempted as an insulating film with both a wide bandgap and a high dielectric constant. Electrical characteristics of AlSiO films are investigated. Leakage current of the AlO film is suppressed by Si addition and is minimized with Si composition ratio of 12%. Capacitance versus voltage (C-V) measurements are carried out for Au/AlSiO/Si MIS structure. Both flat band shift and hysteresis of the C-V characteristics are suppressed by Si addition. A low leakage current is demonstrated for Au/AlSiO/n-SiC MIS structure. 相似文献
70.
Masanori Hino 《Potential Analysis》2002,16(3):249-264
For conservative symmetric diffusions on a general state space (X,m), the short time asymptotic behavior of tlog
X
1
A
T
t
1
B
dm is investigated, where T
t
is the associated semigroup and A and B are measurable subsets of X. It is proved that the superior limit is dominated by the inferior limit up to some absolute constant. When 2 of the associated Dirichlet form is lower bounded, it is shown that the limit exists for any A and B, and is described by the intrinsic metric between them. Applications to infinite-dimensional spaces and fractals are given. 相似文献