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51.
Tolulope Peter Saliu Nao Yazawa Kotaro Hashimoto Kenshu Miyata Ayane Kudo Mayu Horii Mion Kamesawa Thanutchaporn Kumrungsee Noriyuki Yanaka 《International journal of molecular sciences》2022,23(2)
The early detection of diabetic nephropathy (DN) in mice is necessary for the development of drugs and functional foods. The purpose of this study was to identify genes that are significantly upregulated in the early stage of DN progression and develop a novel model to non-invasively monitor disease progression within living animals using in vivo imaging technology. Streptozotocin (STZ) treatment has been widely used as a DN model; however, it also exhibits direct cytotoxicity to the kidneys. As it is important to distinguish between DN-related and STZ-induced nephropathy, in this study, we compared renal responses induced by the diabetic milieu with two types of STZ models: multiple low-dose STZ injections with a high-fat diet and two moderate-dose STZ injections to induce DN. We found 221 genes whose expression was significantly altered during DN development in both models and identified serum amyloid A3 (Saa3) as a candidate gene. Next, we applied the Saa3 promoter-driven luciferase reporter (Saa3-promoter luc mice) to these two STZ models and performed in vivo bioluminescent imaging to monitor the progression of renal pathology. In this study, to further exclude the possibility that the in vivo bioluminescence signal is related to renal cytotoxicity by STZ treatment, we injected insulin into Saa3-promoter luc mice and showed that insulin treatment could downregulate renal inflammatory responses with a decreased signal intensity of in vivo bioluminescence imaging. These results strongly suggest that Saa3 promoter activity is a potent non-invasive indicator that can be used to monitor DN progression and explore therapeutic agents and functional foods. 相似文献
52.
DNA sequence from Aspergillus oryzae genome which, confers on pOK-1 the ability to replicate autonomously in Saccharomyces cerevisiae is described. A hybrid plasmid pOK-1 was constructed from pBR325 and YEp13 fragment containing Leu2+ gene. Asp. oryzae DNA and pOK-1 were cleaved with BamHI, ligated and introduced into Escherichia coli. About 600 recombinant plasmids were obtained. One of them transforms S. cerevisiae SHY3 to Leu2+ with middle efficiency. The plasmid designated as pSB1–2 contained two BamHI fragments (4.3 kb and 4.1 kb) of Asp. oryzae DNA. 相似文献
53.
Shoji Eita Takahashi Ryuji Isogai Shosei Ito Naoto Kubo Masaki Tsukada Takao Fukuyama Hiroyuki 《Metallurgical and Materials Transactions B》2019,50(5):2454-2458
Metallurgical and Materials Transactions B - Normal spectral emissivity of molten Cu-Fe alloy with different compositions was measured at the wavelength of 807 nm using an electromagnetic... 相似文献
54.
Watanabe Masahito Sato Fumiya Abe Raiki Ueda Kyosuke Matsuwaka Daisuke Kudo Fumiaki Narushima Takayuki 《Metallurgical and Materials Transactions B》2019,50(4):1553-1558
Metallurgical and Materials Transactions B - A two-step plasma arc melting process, comprising a first step under Ar-30 pct H2 gas flow and the second step under Ar gas flow, has been... 相似文献
55.
The viscoelastic properties of soybean curd (tofu) as affected by soymilk concentration and type of coagulant 总被引:1,自引:0,他引:1
Yongqiang Cheng Naoto Shimizu & Toshinori Kimura 《International Journal of Food Science & Technology》2005,40(4):385-390
The viscoelastic properties of different types of tofu were investigated. Soymilk concentrations were 5, 6, 7, 8 and 9%. Coagulants used were 30 mm CaSO4 or 30 mm glucono‐delta‐lactone (GDL). As the concentration of soymilk was increased viscosity and handling difficulties increased. A high concentration of soymilk in tofu gave a high break stress and produced hard tofu. The four‐element Burgers model fitted the creep behaviour and both viscous and elastic parameters could be acquired from model analysis, reflecting changes in elasticity and viscosity of tofu. The constant viscous parameter in the model increased with increasing soymilk concentration. The viscous parameters of viscoelastic materials like tofu gel, obtained from small deformation tests, seemed to correlate, to some extent, with the break stress obtained from large deformation tests. For hard tofu production increasing the soymilk concentration within a certain range and the partial replacement of calcium sulphate coagulant by GDL could be effective options. 相似文献
56.
Tatsumi Ishihara Kuninobu Shimose Takanari Kudo Hiroyasu Nishiguchi Taner Akbay Yusaku Takita 《Journal of the American Ceramic Society》2000,83(8):1921-1927
A yttria-stabilized zirconia (YSZ) thin film on an La0.8 Sr0.2 MnO3 porous cathode substrate was prepared, using electrophoretic deposition (EPD) to fabricate a solid oxide fuel cell (SOFC). The electrical conductivity of an La0.8 Sr0.2 MnO3 substrate is satisfactorily high at room temperature; therefore, YSZ powder could be deposited electrophoretically onto an La0.8 Sr0.2 MnO3 substrate without any extra surface treatment, such as a metal coating. Successive repetition of EPD and sintering was required to obtain a film without gas leakage, because of the thermal expansion coefficient mismatch between the YSZ and the La0.8 Sr0.2 MnO3 substrate. On the other hand, the electromotive force of the oxygen concentration in the cell that used YSZ film prepared via EPD increased and attained the theoretical value when the number of deposition and calcination cycles was increased. Six or more successive repetitions were required to obtain a YSZ film without gas leakage. A planar-type SOFC was fabricated, using nickel as the anode and YSZ film (∼10 μm thick) that had been deposited onto the La0.8 Sr0.2 MnO3 substrate as the electrolyte and cathode. The cell exhibited an open circuit voltage of 1.0 V and a maximum power density of 1.5 W/cm2 . Thus, the EPD method could be used as a colloidal process to prepare YSZ thin-film electrolytes for SOFCs. 相似文献
57.
Abnormalities in the Metabolism of Fatty Acids and Triacylglycerols in the Liver of the Goto-Kakizaki Rat: A Model for Non-Obese Type 2 Diabetes 下载免费PDF全文
58.
The oxygen content of silicon nitride with 1 mol% Y2 O3 —Nd2 O3 additive was measured after firing to determine the compositional change during gas-pressure sintering. Oxygen content decreases from 2.5 to 0.94 wt% during firing for 4 h at 1900°C and 10-MPa pressure in N2 . This decrease in oxygen results from the release of SiO gas generated by a thermaldecomposition reaction between Si3 N4 and SiO2 . The resultant sintered silicon nitride material contains less than 1 wt% oxygen. 相似文献
59.
Xin Xu Toshiyuki Nishimura Qing Huang Rong-Jun Xie Naoto Hirosaki Hidehiko Tanaka 《Journal of the American Ceramic Society》2007,90(12):4047-4049
A feasible doping strategy is introduced to synthesize Eu2+ -doped α-Si3 N4 nanowires coated with a thin BN film. The nanowires were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and a fluorescence spectrophotometer. The Eu2+ -doped α-Si3 N4 nanowires emitted strong yellow light, which is related to the 4 f 6 5 d –4 f 7 transition of Eu2+ , upon a broad excitation wavelength range between 250 and 450 nm. The obtained nanowires provided a potential candidate for application in optical nanodevices, as well as in white LEDs. 相似文献
60.
Liquid‐phase sintering of highly Na+ ion conducting Na3Zr2Si2PO12 ceramics using Na3BO3 additive 下载免费PDF全文
Kousuke Noi Kenji Suzuki Naoto Tanibata Akitoshi Hayashi Masahiro Tatsumisago 《Journal of the American Ceramic Society》2018,101(3):1255-1265
Na3Zr2Si2PO12 (NASICON) is a promising material as a solid electrolyte for all‐solid‐state sodium batteries. Nevertheless, one challenge for the application of NASICON in batteries is their high sintering temperature above 1200°C, which can lead to volatilization of light elements and undesirable side reactions with electrode materials at such high temperatures. In this study, liquid‐phase sintering of NASICON with a Na3BO3 (NBO) additive was performed for the first time to lower the NASICON sintering temperature. A dense NASICON‐based ceramic was successfully obtained by sintering at 900°C with 4.8 wt% NBO. This liquid‐phase sintered NASICON ceramic exhibited high total conductivity of ~1 × 10?3 S cm?1 at room temperature and low conduction activation energy of 28 kJ mol?1. Since the room‐temperature conductivity is identical to that of conventional high‐temperature‐sintered NASICON, NBO was demonstrated as a good liquid‐phase sintering additive for NASICON solid electrolyte. In the NASICON with 4.8 wt% NBO ceramic, most of the NASICON grains directly bonded with each other and some submicron sodium borates segregated in particulate form without full penetration to NASICON grain boundaries. This characteristic composite microstructure contributed to the high conductivity of the liquid‐phase sintered NASICON. 相似文献