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981.
Yoshihiko Nomura Yuki Yagi Tokuhiro Sugiura Hirokazu Matsui Norihiko Kato 《Microsystem Technologies》2007,13(8-10):905-910
Authors developed an improved fingertip guiding manipulator that helps visually handicapped persons create mental images of relief sculptures. The manipulator has three functions: (1) an indicating function of knob-moving-direction by a stepping-motor attached at the arm end, (2) a fingertip traction function by a quadrilateral parallel link manipulator, and (3) a fingertip up-down motion function by a linear motion actuator. The former two functions are utilized to represent planer 2D figures, and the last one is to represent the relief sculpture representation together with the former two. Some preliminary experiments were carried out, and the human perceptual thresholds with the up-down motion and the fingertip rotation, and the human kinesthetic following performance were clarified. These thresholds shall be used as the back data for designing mechanical specifications of the proposed fingertip guiding manipulator. 相似文献
982.
Sohei Sukenaga Hiroki Unozawa Yuki Chiba Masanori Tashiro Sakiko Kawanishi Hiroyuki Shibata 《Journal of the American Ceramic Society》2023,106(1):293-305
Optimizing the concentration of molybdenum incorporated in a borosilicate glass matrix is essential in the vitrification of high-level radioactive waste. However, the incorporation limit of MoO3 in fundamental borosilicate systems has been rarely correlated with the local structure of the molybdenum cations. This study investigates the variations in the incorporation limit of MoO3 in ternary sodium borosilicate glass upon varying the B2O3/(SiO2 + B2O3) ratio (i.e., B). The incorporation limit of MoO3 was less than 3 mol% in the low-B region (B < 0.7), where molybdenum cations mainly existed as [MoO4]2−. However, when B was higher than 0.85, the incorporation limit was higher than 6 mol%, and the Raman spectra indicated the presence of octahedrally coordinated molybdenum cations, essential to stabilize the Mo–O–Mo linkage. The variation in the local structure of molybdenum cations can be explained by the available amount of non-framework cations compensating for the negative charge near [MoO4]2−. These results allow the development of glass compositions with a high incorporation limit of MoO3 simply by controlling the local structure near the molybdenum cations. 相似文献
983.
Yuasa Masayoshi Koga Yuki Ueda Hazuki Zayasu Tomonari 《Journal of Applied Electrochemistry》2022,52(8):1173-1186
Journal of Applied Electrochemistry - Nitrogen-doped carbons with a high specific surface area were synthesized from chitosan for use in a catalyst support of a gas diffusion electrode (GDE) for... 相似文献
984.
Behaviormetrika - For two-way contingency tables, as one measure of the relationship between rows and columns, there is a proportional reduction in variation (PRV) measure that compares the... 相似文献
985.
Virtual Reality - The first-person perspective (1PP) and third-person perspective (3PP) have both been adopted in video games. The 1PP can induce a strong sense of immersion, and the 3PP allows... 相似文献
986.
Ephantus Nguma Yuki Tominaga Shinji Yamashita Yurika Otoki Ayaka Yamamoto Kiyotaka Nakagawa Teruo Miyazawa Mikio Kinoshita 《Lipids》2021,56(2):167-180
Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.3 mol% PlsEtn in EtnGpl) and porcine liver (7.2 mol% PlsEtn in EtnGpl) in 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in vivo, and elucidated the possible underlying mechanisms behind it. Dietary EtnGpl-suppressed DMH-induced aberrant crypt with one foci (AC1) and total ACF formation (P < 0.05). ACF suppression by dietary ascidian muscle EtnGpl was higher compared with dietary porcine liver EtnGpl. Additionally, dietary EtnGpl decreased DMH-induced oxidative damage, overproduction of TNF-α, and expression of apoptosis-related proteins in the colon mucosa. The effect of dietary ascidian muscle EtnGpl showed superiority compared with dietary porcine liver EtnGpl. Our results demonstrate the mechanisms by which dietary PlsEtn suppress ACF formation and apoptosis. Dietary PlsEtn attained this suppression by reducing colon inflammation and oxidative stress hence a reduction in DMH-induced intestinal impairment. These findings provide new insights about the functional role of dietary PlsEtn during colon carcinogenesis. 相似文献
987.
Gensuke Okamura Kosuke Ebina Makoto Hirao Ryota Chijimatsu Yasukazu Yonetani Yuki Etani Akira Miyama Kenji Takami Atsushi Goshima Hideki Yoshikawa Takuya Ishimoto Takayoshi Nakano Masayuki Hamada Takashi Kanamoto Ken Nakata 《International journal of molecular sciences》2021,22(1)
Synovial mesenchymal stem cell (SMSC) is the promising cell source of cartilage regeneration but has several issues to overcome such as limited cell proliferation and heterogeneity of cartilage regeneration ability. Previous reports demonstrated that basic fibroblast growth factor (bFGF) can promote proliferation and cartilage differentiation potential of MSCs in vitro, although no reports show its beneficial effect in vivo. The purpose of this study is to investigate the promoting effect of bFGF on cartilage regeneration using human SMSC in vivo. SMSCs were cultured with or without bFGF in a growth medium, and 2 × 105 cells were aggregated to form a synovial pellet. Synovial pellets were implanted into osteochondral defects induced in the femoral trochlea of severe combined immunodeficient mice, and histological evaluation was performed after eight weeks. The presence of implanted SMSCs was confirmed by the observation of human vimentin immunostaining-positive cells. Interestingly, broad lacunae structures and cartilage substrate stained by Safranin-O were observed only in the bFGF (+) group. The bFGF (+) group had significantly higher O’Driscoll scores in the cartilage repair than the bFGF (−) group. The addition of bFGF to SMSC growth culture may be a useful treatment option to promote cartilage regeneration in vivo. 相似文献
988.
Nozomi Yabuuchi Huixian Hou Nao Gunda Yuki Narita Hirofumi Jono Hideyuki Saito 《International journal of molecular sciences》2021,22(4)
Endogenous factors involved in the progression of cisplatin nephropathy remain undetermined. Here, we demonstrate the toxico-pathological roles of indoxyl sulfate (IS), a sulfate-conjugated uremic toxin, and sulfotransferase 1A1 (SULT1A1), an enzyme involved in its synthesis, in cisplatin-induced acute kidney injury using Sult1a1-deficient (Sult1a1-/- KO) mice. With cisplatin administration, severe kidney dysfunction, tissue damage, and apoptosis were attenuated in Sult1a1-/- (KO) mice. Aryl hydrocarbon receptor (AhR) expression was increased by treatment with cisplatin in mouse kidney tissue. Moreover, the downregulation of antioxidant stress enzymes in wild-type (WT) mice was not observed in Sult1a1-/- (KO) mice. To investigate the effect of IS on the reactive oxygen species (ROS) levels, HK-2 cells were treated with cisplatin and IS. The ROS levels were significantly increased compared to cisplatin or IS treatment alone. IS-induced increases in ROS were reversed by downregulation of AhR, xanthine oxidase (XO), and NADPH oxidase 4 (NOX4). These findings suggest that SULT1A1 plays toxico-pathological roles in the progression of cisplatin-induced acute kidney injury, while the IS/AhR/ROS axis brings about oxidative stress. 相似文献
989.
Xia Zhang Rikiya Taoka Dage Liu Yuki Matsuoka Yoichiro Tohi Yoshiyuki Kakehi Mikio Sugimoto 《International journal of molecular sciences》2021,22(8)
RRM1—an important DNA replication/repair enzyme—is the primary molecular gemcitabine (GEM) target. High RRM1-expression associates with gemcitabine-resistance in various cancers and RRM1 inhibition may provide novel cancer treatment approaches. Our study elucidates how RRM1 inhibition affects cancer cell proliferation and influences gemcitabine-resistant bladder cancer cells. Of nine bladder cancer cell lines investigated, two RRM1 highly expressed cells, 253J and RT112, were selected for further experimentation. An RRM1-targeting shRNA was cloned into adenoviral vector, Ad-shRRM1. Gene and protein expression were investigated using real-time PCR and western blotting. Cell proliferation rate and chemotherapeutic sensitivity to GEM were assessed by MTT assay. A human tumor xenograft model was prepared by implanting RRM1 highly expressed tumors, derived from RT112 cells, in nude mice. Infection with Ad-shRRM1 effectively downregulated RRM1 expression, significantly inhibiting cell growth in both RRM1 highly expressed tumor cells. In vivo, Ad-shRRM1 treatment had pronounced antitumor effects against RRM1 highly expressed tumor xenografts (p < 0.05). Moreover, combination of Ad-shRRM1 and GEM inhibited cell proliferation in both cell lines significantly more than either treatment individually. Cancer gene therapy using anti-RRM1 shRNA has pronounced antitumor effects against RRM1 highly expressed tumors, and RRM1 inhibition specifically increases bladder cancer cell GEM-sensitivity. Ad-shRRM1/GEM combination therapy may offer new treatment options for patients with GEM-resistant bladder tumors. 相似文献
990.
Keisuke Fukumura Yuki Narimatsu Shogo Moriwaki Eiko Iwakoshi-Ukena Megumi Furumitsu Kazuyoshi Ukena 《International journal of molecular sciences》2021,22(9)
A high-fat diet (HFD) quickly induces obesity with insulin resistance and hyperglycemia. We previously reported that a novel hypothalamic small protein, named neurosecretory protein GL (NPGL), stimulates feeding and fat accumulation in mice. However, the effects of NPGL on insulin sensitivity and glucose homeostasis remain unknown. Hence, we subjected NPGL-precursor gene (Npgl)-overexpressing mice to the oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (IPITT) under normal chow (NC) and HFD conditions. Npgl overexpression promoted body mass gain and tended to increase food intake of NC-fed mice, whereas it had little effect on HFD-fed mice. The OGTT showed elevated blood glucose and insulin levels in Npgl-overexpressing NC-fed mice 15 min after glucose administration. Both the OGTT and IPITT demonstrated that Npgl overexpression decreased blood glucose levels in HFD-fed mice 60 min after glucose and insulin treatments. Notably, Npgl overexpression increased adipose tissue masses only in NC-fed mice, and it decreased blood glucose and insulin levels in HFD-fed mice at the experimental end point. It also increased the mRNA expression of galanin, one of the feeding and metabolic regulatory neuropeptides, in the hypothalamus of HFD-fed mice. Therefore, NPGL may alleviate HFD-induced hyperglycemia and insulin resistance in mice. 相似文献