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51.
Jannatul Aklima Sawaros Onchaiya Tomonori Saotome Punitha Velmurugan Taihei Motoichi Jannatul Naima Yutaka Kuroda Yoshihiro Ohta 《International journal of molecular sciences》2022,23(17)
Protein quality control is essential for cellular homeostasis. In this study, we examined the effect of improperly folded proteins that do not form amyloid fibrils on mitochondria, which play important roles in ATP production and cell death. First, we prepared domain 3 of the dengue envelope protein in wild type and four mutants with widely different biophysical properties in misfolded/aggregated or destabilized states. The effects of the different proteins were detected using fluorescence microscopy and Western blotting, which revealed that three of the five proteins disrupted both inner and outer membrane integrity, while the other two proteins, including the wild type, did not. Next, we examined the common characteristics of the proteins that displayed toxicity against mitochondria by measuring oligomer size, molten globule-like properties, and thermal stability. The common feature of all three toxic proteins was thermal instability. Therefore, our data strongly suggest that thermally unstable proteins generated in the cytosol can cause cellular damage by coming into direct contact with mitochondria. More importantly, we revealed that this damage is not amyloid-specific. 相似文献
52.
Because functional diseases of the brain can cause disabilities related to human movement control, a compensation method was
developed for improving the performance of hand movements. The compensation for human hand movements can be carried out by
adding an assistant force that is generated from artificial equipment attached to a human arm. From the experiment on visual
target tracking, it was found that the tracking trajectory was adequately represented by a dynamic model of the motion of
an articulated industrial robot arm, and the different abilities for movement control among healthy people and patients were
classified by different model parameters as position loop gain, velocity loop gain, and response delay. Dynamic force compensation
was approached by considering the different control features of the patients. The effectiveness of the proposed compensation
method was verified in a simulation study on an actual industrial robot arm. A human-machine interface, e.g., a brain-computer
interface (BCI), for realizing the control of artificial equipment to compensate for human hand movements is also presented
and discussed. 相似文献
53.
Yu-Ping Wang Sen-Wei Xie Li-Hui Wang Hongjin Xu Satoshi Tabata Masatoshi Ishikawa 《计算机科学技术学报》2022,37(3):666-679
Computed tomography (CT) generates cross-sectional images of the body. Visualizing CT images has been a challenging problem. The emergence of the augmented and virtual reality technology has provided promising solutions. However, existing solutions suffer from tethered display or wireless transmission latency. In this paper, we present ARSlice, a proof-of-concept prototype that can visualize CT images in an untethered manner without wireless transmission latency. Our ARSlice prototype consists of two parts, the user end and the projector end. By employing dynamic tracking and projection, the projector end can track the user-end equipment and project CT images onto it in real time. The user-end equipment is responsible for displaying these CT images into the 3D space. Its main feature is that the user-end equipment is a pure optical device with light weight, low cost, and no energy consumption. Our experiments demonstrate that our ARSlice prototype provides part of six degrees of freedom for the user, and a high frame rate. By interactively visualizing CT images into the 3D space, our ARSlice prototype can help untrained users better understand that CT images are slices of a body. 相似文献
54.
Soichiro Sawamura Katsunari Makino Maho Ide Shuichi Shimada Ikko Kajihara Takamitsu Makino Masatoshi Jinnin Satoshi Fukushima 《International journal of molecular sciences》2022,23(12)
Systemic sclerosis (SSc) is characterized by excessive collagen deposition in the skin and internal organs. Activated fibroblasts are the key effector cells for the overproduction of type I collagen, which comprises the α1(I) and α2(I) chains encoded by COL1A1 and COL1A2, respectively. In this study, we examined the expression patterns of α1(I) and α2(I) collagen in SSc fibroblasts, as well as their co-regulation with each other. The relative expression ratio of COL1A1 to COL1A2 in SSc fibroblasts was significantly higher than that in control fibroblasts. The same result was observed for type I collagen protein levels, indicating that α2(I) collagen is more elevated than α2(I) collagen. Inhibition or overexpression of α1(I) collagen in control fibroblasts affected the α2(I) collagen levels, suggesting that α1(I) collagen might act as an upstream regulator of α2(I) collagen. The local injection of COL1A1 small interfering RNA in a bleomycin-induced SSc mouse model was found to attenuate skin fibrosis. Overall, our data indicate that α2(I) collagen is a potent regulator of type I collagen in SSc; further investigations of the overall regulatory mechanisms of type I collagen may help understand the aberrant collagen metabolism in SSc. 相似文献
55.
Hiroshi Funaakubo Masatoshi Mitsuya Norimasa Nukaga Katsuyuki Ishikawa 《Integrated ferroelectrics》2013,141(1-4):225-234
Abstract SrBi2(Ta0.7Nb0.3)2O9 (SBTN) films were first prepared on (111)Pt/Ti/SiO2/Si substrates by MOCVD from only two organometallic source bottles. Bi(CH3)3 and the mixture of Sr[Ta(O°C2H5)6]2 and Sr[Nb(O°C2H5)6]2 were used as source materials. High compositional reproducibility was obtained; the Nb/(Ta+Nb) ratio was the same as the mixing ratio of the source. Sr/(Ta+Nb) and Bi/(Ta+Nb) ratios can be controlled by the reactor pressure and the input gas flow rate ratio of the source gases. Almost single phase of SBTN was obtained for the film deposited at 500°C and the following heat-treated at 800°C in O2 atmosphere. Pr and Ec values of 330 nm-thick SBTN film were 8.5 μC/cm2 and 91 kV/cm, respectively and were larger than those of SrBi2Ta2O9 film. There was no degradation after 5x1010 cycles polarization switching. 相似文献
56.
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58.
This paper derives performance limitations for disturbance rejection of scalar systems under information constraints subject to either bounded or Gaussian disturbances. Two kinds of disturbance are treated in a unified manner, using appropriate entropies and distortions. It is shown that the achievable performance cannot be improved even if the maximum information constraint is relaxed to an average information constraint. Another observation is that, while the information constraints are weaker than bit-rate or signal-to-noise ratio constraints on the communication channel, the same performance levels are achieved by the best encoder and decoder for disturbance rejection with the information constraints. 相似文献
59.
Shota Sato Kunihiko Ohta Kaoru Kojima Takuya Kozeki Tetsuo Ohmachi Takashi Yoshida 《Journal of Applied Glycoscience》2016,63(1):13
Xyloglucan is a major hemicellulosic component in plant cell walls. Phytopathogenic fungi secrete cell wall-degrading enzymes on their infection to hosts, while the nature of the cell wall-lytic enzymes of such fungi are yet to be fully understood. Verticillium dahliae is a soil-borne fungus that causes vascular wilt diseases in a variety of commercially important crops worldwide. We purified two types of xyloglucanases, XEG12A and XEG74B, from the culture of naturally isolated Verticillium dahliae strain 2148. XEG12A showed a molecular size of 23 kDa with its maximal activity at pH 7.5. XEG12A specifically hydrolyzed xyloglucan with no activity on other β-glucans. XEG74B had a molecular size of 110 kDa with its optimum pH at 6.0. XEG74B primarily hydrolyzed xyloglucan, with a slight activity on β-1,3-1,4-glucan. Analysis of hydrolytic products of xyloglucanooligasaccharide (XXXGXXXG) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed that the both enzymes cleaved β-1,4-glucosidic linkage at the position of unbranched chain, while XEG74B showed a little fluctuation with the cleavage site. Both enzymes did not hydrolyzed xyloglucanoheptasaccharide (XXXG) at all. N-Terminal and internal amino acid sequencing of the enzymes revealed that XEG12A and XEG74B belonged to Glycoside Hydrolase (GH) Families 12 and 74, respectively. Based on these results we concluded that V. dahliae XEG12A and XEG74B were xyloglucan-specific endo-β-1,4-glucanases (EC 3.2.1.151). 相似文献
60.
Yutaka Kawahara Atsushi Nakayama Masatoshi Shioya Masaki Tsuji Hideki Yamane Tadahisa Iwata 《Journal of Materials Science》2012,47(4):1887-1892
Structure of poly(dioxanone) (PPDX) fibers produced through a two-step melt-spinning process with an additional short-period
annealing above the melting temperature of PPDX was investigated and the effect of annealing on the degradation behavior was
discussed. The morphological study carried out by etching the fibers using a phosphate or permanganate solution suggested
that the fibers take a skin–core structure, and both the skin layer and the core region consist of a bundle of microfibrils.
The micro-beam X-ray diffraction analysis revealed that the short-period annealing in the production process only slightly
promotes the crystallization in the skin layer but contributes to increasing the packing of amorphous chains near the skin,
which seems to be the controlling factor of the hydrolytic degradation behavior of the fibers. 相似文献