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191.
Yasuharu Takaku Hiroshi Suzuki Isao Ohta Takami Tsutsui Haruko Matsumoto Masatsugu Shimomura Takahiko Hariyama 《Proceedings. Biological sciences / The Royal Society》2015,282(1802)
Although extremely useful for a wide range of investigations, the field emission scanning electron microscope (FE-SEM) has not allowed researchers to observe living organisms. However, we have recently reported that a simple surface modification consisting of a thin extra layer, termed ‘NanoSuit’, can keep organisms alive in the high vacuum (10−5 to 10−7 Pa) of the SEM. This paper further explores the protective properties of the NanoSuit surface-shield. We found that a NanoSuit formed with the optimum concentration of Tween 20 faithfully preserves the integrity of an organism''s surface without interfering with SEM imaging. We also found that electrostatic charging was absent as long as the organisms were alive, even if they had not been coated with electrically conducting materials. This result suggests that living organisms possess their own electrical conductors and/or rely on certain properties of the surface to inhibit charging. The NanoSuit seems to prolong the charge-free condition and increase survival time under vacuum. These findings should encourage the development of more sophisticated observation methods for studying living organisms in an FE-SEM. 相似文献
192.
A newly developed high-performance liquid chromatography method was used to measure four nonpolar glycolipids in developing rat brain. The accumulation patterns of nonhydroxy- and hydroxycerebroside fatty acid esters were similar to those of myelin cerebrosides. In contrast, both monogalactosyl diacylglycerol and alkylgalactolipids reached maximal levels at the early stages of myelination. 相似文献
193.
It has been shown that Piricularia oryzae could grow in the presence of amino acid, even in the absence of a proper carbon source and that the first step of utilization was the formation of the corresponding α-keto acid by deamination in the medium. For further confirmation of this process, DL-valine was used as the amino acid to be tested in the current experiment. In each of the three cases, that is, DL-valine alone, DL-valine plus arsenite and DL-valine plus sucrose, the dimethlpyruvic acid formed was identified as its 2, 4-dinitrophenylhydrazone. Even in the presence of a sufficient amount of sucrose, some parts of DL-valine added were found to be utilized as a carbon source through the conversion to its α-keto analog. 相似文献
194.
Megu Yamaguchi Baden Kenji Fukui Yoshiya Hosokawa Hiromi Iwahashi Akihisa Imagawa Iichiro Shimomura 《PloS one》2015,10(12)
Aims
Viral infection is associated with pancreatic beta cell destruction in fulminant type 1 diabetes mellitus. The aim of this study was to investigate the acceleration and protective mechanisms of beta cell destruction by establishing a model of viral infection in pancreatic beta cells.Methods
Polyinosinic:polycytidylic acid was transfected into MIN6 cells and insulin-producing cells differentiated from human induced pluripotent stem cells via small molecule applications. Gene expression was analyzed by real-time PCR, and apoptosis was evaluated by caspase-3 activity and TUNEL staining. The anti-apoptotic effect of Exendin-4 was also evaluated.Results
Polyinosinic:polycytidylic acid transfection led to elevated expression of the genes encoding IFNα, IFNβ, CXCL10, Fas, viral receptors, and IFN-inducible antiviral effectors in MIN6 cells. Exendin-4 treatment suppressed the elevated gene expression levels and reduced polyinosinic:polycytidylic acid-induced apoptosis both in MIN6 cells and in insulin-producing cells from human induced pluripotent stem cells. Glucagon-like peptide-1 receptor, protein kinase A, and phosphatidylinositol-3 kinase inhibitors counteracted the anti-apoptotic effect of Exendin-4.Conclusions
Polyinosinic:polycytidylic acid transfection can mimic viral infection, and Exendin-4 exerted an anti-apoptotic effect both in MIN6 and insulin-producing cells from human induced pluripotent stem cells. 相似文献195.
196.
In recent years, parametric speakers have been used in various circumstances. However, nothing has yet been demonstrated about the safety of parametric speakers for the human body. Therefore, we studied their effects on physiological functions. Nine male subjects participated in this study. They completed three consecutive sessions: a 20-min quiet period as a baseline, a 45-min mental task period with a general speaker or a parametric speaker, and a 20-min recovery period. We measured electrocardiogram (ECG), photoplethysmogram (PTG), electroencephalogram (EEG), blood pressure (BP), and baroreflex sensitivity (BRS). Two experiments, one with a general speaker (the general condition), the other with a parametric speaker (the parametric condition), were conducted at the same time of day on separate days. To examine the effects of the parametric speaker, a two-way repeated measures ANOVA (speaker factor and time factor) was conducted. We found that sympathetic nervous activity and second derivative of PTG in task period and recovery period during the parametric condition were significantly lower than those indications during the general condition. Furthermore, Δ parasympathetic nervous activity during the parametric condition in task period and recovery period tended to be smaller than that during the general condition. The results suggested that the burden of the parametric speaker is lower than that of the general speaker for physiological functions, especially those of the cardiovascular system. Furthermore, we verified that the reaction time with the parametric speaker is shorter than that with the general speaker. 相似文献
197.
Yoshitada Tanabe Fumihito Tajima Yuki Nakamura Eriko Shibasaki Mai Wakejima Takashi Shimomura Rie Murai Yoshiyuki Murawaki Koichi Hashiguchi Takamasa Kanbe Toshiya Saeki Miho Ichiba Yoko Yoshida Masahiro Mitsunari Soichi Yoshida Jun-ichiro Miake Yasutaka Yamamoto Naoki Nagata Tasuku Harada Akihiro Kurimasa Ichiro Hisatome Naoki Terakawa Yoshikazu Murawaki Goshi Shiota 《Biochemical and biophysical research communications》2011,(4):769
198.
Takuya Mori Norikazu Maeda Kana Inoue Ryohei Sekimoto Yu Tsushima Keisuke Matsuda Masaya Yamaoka Takayoshi Suganami Hitoshi Nishizawa Yoshihiro Ogawa Tohru Funahashi Iichiro Shimomura 《PloS one》2013,8(10)
Aims
Ephrin-B1 (EfnB1) was selected among genes of unknown function in adipocytes or adipose tissue and subjected to thorough analysis to understand its role in the development of obesity.Methods and Results
EfnB1 mRNA and protein levels were significantly decreased in adipose tissues of obese mice and such reduction was mainly observed in mature adipocytes. Exposure of 3T3-L1 adipocytes to tumor necrosis factor-α (TNF-α) and their culture with RAW264.7 cells reduced EFNB1 levels. Knockdown of adipose EFNB1 increased monocyte chemoattractant protein-1 (Mcp-1) mRNA level and augmented the TNF-α-mediated THP-1 monocyte adhesion to adipocytes. Adenovirus-mediated adipose EFNB1-overexpression significantly reduced the increase in Mcp-1 mRNA level induced by coculture of 3T3-L1 adipocytes with RAW264.7 cells. Monocyte adherent assay showed that adipose EfnB1-overexpression significantly decreased the increase of monocyte adhesion by coculture with RAW264.7 cells. TNF-α-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) was reduced by EFNB1-overexpression.Conclusions
EFNB1 contributes to the suppression of adipose inflammatory response. In obesity, reduction of adipose EFNB1 may accelerate the vicious cycle involved in adipose tissue inflammation. 相似文献199.
Di Hu Atsunori Fukuhara Yugo Miyata Chieko Yokoyama Michio Otsuki Shinji Kihara Iichiro Shimomura 《PloS one》2013,8(2)
Adiponectin is exclusively expressed in adipose tissues and exhibits protective effects against cardiovascular and metabolic diseases. It enhances AMP-activated kinase (AMPK) and peroxisome proliferator-activated receptor α (PPARα) signaling in the liver and skeletal muscles, however, its signaling pathways in macrophages remain to be elucidated. Here, we show that adiponectin upregulated the expression of vascular endothelial growth factor (VEGF)-C, and induced phosphorylation of extracellular signal-regulated kinase (ERK) in macrophages. Inhibition of Syk abrogated adiponectin-induced VEGF-C expression and ERK phosphorylation. Furthermore, inhibition of ERK blocked the induction of VEGF-C gene. Inhibition of Syk, but not that of ERK, abrogated adiponectin-induced expression of cyclooxygenase (COX)-2, tissue inhibitor of metalloproteinase (TIMP)-1, and interleukin (IL)-6. These results indicate that adiponectin regulates VEGF-C expression via Syk-ERK pathway in macrophages. 相似文献
200.
Nozomu Hibi Seiya Chiba Tokuji Shimomura 《Bioscience, biotechnology, and biochemistry》2013,77(9):1805-1812
A neutral α-glucosidase was purified from pig serum by precipitation with ammonium sulfate, chromatographies on DEAE-cellulose and -Sephadex A–50, and gel filtration on Bio-Gel P–300 and Sephadex G–200. The purified enzyme was homogeneous in ultracentrifugal and disc electrophoretic analysis. The sedimentation coefficient (s20,w) was calculated to be 10.7 S, and the isoelectric point, 4.0. The molecular weight was estimated to be approximately 2.7 × 105 by thin-layer gel filtration and SDS-disc electrophoresis.The enzyme exhibited also glucoamylase activity. The optimal pH was found to be in the pH range of 6.0 to 7.0 for maltose and soluble starch. The ratio of velocity of hydrolysis for maltose (Km, 0.72 mg/ml), soluble starch (Km, 9.8 mg/ml) and shellfish glycogen (Km, 55.6 mg/ml) was calculated to be 100: 110: 5.15 in this order. 相似文献