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11.
Junya Hanaguri Harumasa Yokota Akifumi Kushiyama Sakura Kushiyama Masahisa Watanabe Satoru Yamagami Taiji Nagaoka 《International journal of molecular sciences》2022,23(3)
We investigated the effect of tofogliflozin, a sodium-dependent glucose cotransporter 2 inhibitor (SGLT2i), on retinal blood flow dysregulation, neural retinal dysfunction, and the impaired neurovascular coupling in type 2 diabetic mice. Tofogliflozin was added to mouse chow to deliver 5 mg/kg/day and 6-week-old mice were fed for 8 weeks. The longitudinal changes in the retinal neuronal function and blood flow responses to systemic hyperoxia and flicker stimulation were evaluated every 2 weeks in diabetic db/db mice that received tofogliflozin (n =6) or placebo (n = 6) from 8 to 14 weeks of age. We also evaluated glial activation and vascular endothelial growth factor (VEGF) expression by immunofluorescence. Tofogliflozin treatment caused a sustained decrease in blood glucose in db/db mice from 8 weeks of the treatment. In tofogliflozin-treated db/db mice, both responses improved from 8 to 14 weeks of age, compared with vehicle-treated diabetic mice. Subsequently, the electroretinography implicit time for the oscillatory potential was significantly improved in SGLT2i-treated db/db mice. The systemic tofogliflozin treatment prevented the activation of glial fibrillary acidic protein and VEGF protein expression, as detected by immunofluorescence. Our results suggest that glycemic control with tofogliflozin significantly improved the impaired retinal neurovascular coupling in type 2 diabetic mice with the inhibition of retinal glial activation. 相似文献
12.
Masaki Saito Marina Hirano Tomohiro Izumi Yu Mori Kentaro Ito Yurika Saitoh Nobuo Terada Takeya Sato Jun Sukegawa 《International journal of molecular sciences》2022,23(4)
The primary cilium is a hair-like immotile organelle with specific membrane receptors, including the receptor of Hedgehog signaling, smoothened. The cilium organized in preosteoblasts promotes differentiation of the cells into osteoblasts (osteoblast differentiation) by mediating Hedgehog signaling to achieve bone formation. Notably, 4.1G is a plasma membrane-associated cytoskeletal protein that plays essential roles in various tissues, including the peripheral nervous system, testis, and retina. However, its function in the bone remains unexplored. In this study, we identified 4.1G expression in the bone. We found that, in the 4.1G-knockout mice, calcium deposits and primary cilium formation were suppressed in the trabecular bone, which is preosteoblast-rich region of the newborn tibia, indicating that 4.1G is a prerequisite for osteoblast differentiation by organizing the primary cilia in preosteoblasts. Next, we found that the primary cilium was elongated in the differentiating mouse preosteoblast cell line MC3T3-E1, whereas the knockdown of 4.1G suppressed its elongation. Moreover, 4.1G-knockdown suppressed the induction of the cilia-mediated Hedgehog signaling and subsequent osteoblast differentiation. These results demonstrate a new regulatory mechanism of 4.1G in bone formation that promotes the primary ciliogenesis in the differentiating preosteoblasts and induction of cilia-mediated osteoblast differentiation, resulting in bone formation at the newborn stage. 相似文献
13.
K Hashimoto C Azuma Y Tokugawa T Nobunaga TA Aki Y Matsui T Yanagida H Izumi F Saji Y Murata 《Canadian Metallurgical Quarterly》1997,28(7):862-865
An unusual clinical presentation of a patient with neuronal intestinal dysplasia is presented. A 46-year-old male noted a palpable mass in the right lower quadrant of his abdomen for two months. A computed axial tomographic scan showed a thickened wall of the cecum with a tumor-like appearance. The excised specimen consisted of a mass caused by the thickened, edematous wall of the dilated cecum and appendix. The wall of the cecum and appendix measured up to 2.5 and 0.8 cm, respectively, in thickness. Microscopic studies showed extensive hyperplasia and hypertrophy of the ganglia and nerve plexuses and hypertrophy of the muscularis propria, consistent with neuronal intestinal dysplasia. 相似文献
14.
15.
Noriaki Takagi Yoshinobu Izumi Kimiko Ema Tadashi Yamamoto Kazushige Nishizawa 《溶剂提取与离子交换》2013,31(6):1461-1471
ABSTRACT Dicyclohexano- 18-crown-6 (DC18C6), dissolved in chloroform, 1-octanol, toluene or cyclohexane, was irradiated by 60Co γ-rays. Radiolytic destruction of DC18C6, measured by gas chromatography, decreased in the order: chloroform > cyclohexane > 1-octanol > toluene. Distribution coefficients in the solvent extraction of strontium from nitric acid solution were measured. These distribution coefficients were minimally affected by γ-irradiation in toluene solution, but decreased with the absorbed dose in chloroform solution. It was suggested that the distribution coefficient for the liquid-liquid extraction system was influenced by radiolytic products. The effect of radiolytic products on the distribution coefficients was evaluated by considering DC18C6 remaining in the organic phase after irradiation. The distribution coefficient measured for the organic phase with radiolytic products was larger than that without radiolytic products. The radiolytic products were thus shown to contribute to the increase in the distribution coefficient. 相似文献
16.
Izumi Taniguchi Shinya Nakajima Zhumabay Bakenov 《Chemical Engineering Communications》2013,200(10):1292-1301
A novel technique has been developed to directly produce fine ceramic powders from liquid solution via spray pyrolysis in a fluidized bed reactor (SPFBR). Using this technique the preparation of LiM0.15Mn1.85O4 (M = Mn, Co, Al, and Fe), which are the most promising cathode materials for lithium-ion batteries, has been carried out at a superficial velocity U0 of 0.71 m/s, a reactor temperature T of 800°C, and a static bed height Ls of 100 mm. The as-prepared powders were spherical nanostructured particles that comprised primary particles of a few tens of nanometers in size, and they exhibited a pure cubic spinel structure without any impurities in the XRD patterns. The chemical composition of as-prepared samples showed good agreement with the theoretical values that proved stoichiometric formulae of the compounds. The specific surface area of as-prepared LiM0.15Mn1.85O4 (M = Mn, Co, Al, and Fe) powders decreases with increasing the static bed height in each doping metal, while the crystallite size increases with the static bed height. As a result, the as-prepared powders showed larger crystallite size and smaller specific surface area than those prepared by conventional spray pyrolysis. 相似文献
17.
Zhi-xue Tian Akifumi Uozumi Ikutaro Hamada Susumu Yanagisawa Hidetoshi Kizaki Kouji Inagaki Yoshitada Morikawa 《Nanoscale research letters》2013,8(1):203
First-principles calculations were performed to investigate the effect of Pd concentration and oxygen vacancies on the stability of Pd at LaFeO3 surfaces. We found a much stronger tendency of Pd to segregate by taking the aggregation of Pd at LaFe1-xPdxO3-y surfaces into consideration, resulting in a pair of Pd-Pd around a vacancy. Moreover, we predicted that one oxygen-vacancy-containing FeO2-terminated surfaces would be stable at high temperatures by comparing the stability of LaFe1-xPdxO3-y surfaces, which further supports our previous conclusion that a Pd-containing perovskite catalyst should be calcined at 1,073 K or higher temperatures in air to enhance the segregation of Pd in the vicinity of surfaces to rapidly transform the Pd catalyst from oxidized to reduced states on the perovskite support. 相似文献
18.
Spray pyrolysis synthesis of nanostructured LiFexMn2−xO4 cathode materials for lithium-ion batteries
A series of partially Fe-substituted lithium manganese oxides LiFexMn2−xO4 (0 ≦ x ≦ 0.3) was successfully synthesized by an ultrasonic spray pyrolysis technique. The resulting powders were spherical nanostructured particles which comprised the primary particles with a few tens of nanometer in size, while the morphology changed from spherical and porous to spherical and dense with increasing Fe substitution. The densification of particles progressed with the amount of Fe substitution. All the samples exhibited a pure cubic spinel structure without any impurities in the XRD patterns.The as-prepared powders were then sintered at 750 °C for 4 h in air. However, the particles morphology and pure spinel phase of LiFexMn2−xO4 powders did not change after sintering. The as-sintered powders were used as cathode active materials for lithium-ion batteries, and cycle performance of the materials was investigated using half-cells Li/LiFexMn2−xO4. The first discharge capacity of Li/LiFexMn2−xO4 cell in a voltage 3.5-4.4 V decreased as the value x increased, however these cells exhibited stable cycling performance at wide ranges of charge-discharge rates. 相似文献
19.
Izumi Satake John H. XinTu Tianming Aran HansuebsaiKenji Ando Tetsuya SatoKanji Kajiwara Seiji Ohsawa 《Progress in Organic Coatings》2011,72(3):528-540
This article compares color assessments of automotive exteriors at four locations in China, Thailand and Japan. This study employed painted panels of twelve colors, thirty sensory words and fifteen pairs of emotion variables. It also used reference figures of nine cars that included four styling categories, namely sedans, compacts, sport utility vehicles and sports cars. The results of like-dislike tests revealed that basic automotive exterior colors, such as black, white and red, were highly preferred across locations. However, geographical differences are apparent in the preference for some non-basic colors. To elucidate these geographical differences, a Chi-square test and principal component analysis were performed on the data on emotion variables. The results revealed both similarities and differences in color preferences among the four locations. Color preferences were similar in Hong Kong and Shanghai when simply evaluated by color samples. However, similar preferences for automotive exterior colors were observed in Hong Kong, Kyoto and Bangkok, but not in Shanghai. These results suggest that there is fluctuation in the emotion evoked by a color when the color is considered in the context of automotive exteriors. Therefore, this study indicates that automotive sales can be secured in the global marketplace by creating a single palette of exterior colors based on similar color preferences across countries. However, these results also indicate that preparing market-specific automotive-color line-ups can be an effective marketing strategy. 相似文献
20.
Satoshi Murakami Kazuhiro Satou Taturo Kijima Masataka Watanabe Taeko Izumi 《European Journal of Lipid Science and Technology》2011,113(4):450-458
The enantiopure of (R)‐(?) MαNPA was allowed to react with racemic 18‐(tert‐butyldimethylsilyloxy)‐5‐octadecayne‐7‐ol which was derived from dodecane‐1,12‐diol, yielding diastereomeric esters mixture. These racemic esters were easily separated by HPLC on silica‐gel. The absolute configurations of the first‐eluted diastereomeric esters from the separated esters were determined using 1H NMR anisotropy method. Analysis on 1H NMR spectra and HPLC elution time of the synthesized esters and those of MαNP ester derived from natural methyl‐12‐hydroxystealate showed that the absolute configuration of natural 12‐hydroxystearic acid was R form, and the enantiomeric excess was over 99%. 相似文献