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Preliminary Investigation of Copper(II) Ion Binding or Complex Coordination in Lysozeme Molecules
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作者 Kou Takahashi Ryotaro Miyazaki +2 位作者 Daisuke Nakane Temitayo O. Aiyelabola Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 2024年第4期98-103,共6页
Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed... Hydrophobic Val derivative Schiff base copper(II) complexes and dipeptide (AlaAla, GlyGly) derivative Schiff base copper(II) complexes were introduced into egg white lysozyme. X-ray crystal structure analysis revealed amino acid derivative Schiff base copper(II) complexes were obtained. Herein we discuss primarily on the binding mode of copper(II) of the complexes obtained with egg white lysozyme. The electron density of copper(II) ions was confirmed by X-ray crystal structure analysis. The Val derivative Schiff base copper(II) complex was weakly bound at Arg114 of egg white lysozyme. In other copper(II) complexes, binding of copper(II) ions with dissociated ligands to various residues was observed. The binding sites of copper(II) ions were compared with computational scientific predictions. 展开更多
关键词 COPPER Schiff Base LYSOZYME Metal-Protein Binding Computational Methods
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Refinement of Adaptive Dynamical Simulation of Quantum Mechanical Double Slit Interference Phenomenon
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作者 Tadashi Ando Andrei Khrennikov Ichiro Yamato 《Journal of Modern Physics》 2024年第3期239-249,共11页
We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. S... We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. Several properties such as concave single slit pattern and large influence of slight displacement of the emission position were different from the experimental results. In this study we tried other slit conditions and obtained consistent patterns with experiments. We do not claim that the adaptive dynamics is the principle of quantum mechanics, but the present results support the probability of adaptive dynamics as the candidate of the basis of quantum mechanics. We discuss the advantages of the adaptive dynamical view for foundations of quantum mechanics. 展开更多
关键词 Double Slit Interference Adaptive Dynamics Quantum Mechanics Particle Model Simulation
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Coordination and Photoisomerization of Azobenzene-Amino Acid Schiff Base Copper(II) Complexes to Lysozyme
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作者 Yuto Kuroda Ryotaro Miyazaki +2 位作者 Daiki Shimonishi Daisuke Nakane Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第3期34-44,共11页
In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a we... In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a well-known protein, to change ligand conformation under binding to lysozyme. Among several spectroscopic investigations, ESR clearly showed that the nitrogen atom of the amino acid residue of lysozyme was bound to the paramagnetic copper(II) ion of the complex, and UV light irradiation confirmed photoisomerization of the azobenzene moiety of the ligand to cis-form. The binding mode was considered by means of spectroscopic as well as computational methods, whereas complete crystallographic verification was still a preliminary stage. 展开更多
关键词 AZOBENZENE Schiff Base Copper Amino Acid LYSOZYME Artificial Metalloprotein
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Elucidating the clinical and immunological value of m6A regulatormediated methylation modification patterns in adrenocortical carcinoma
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作者 WENHAO XU HAOMING LI +8 位作者 YASIR HAMEED MOSTAFA A.ABDEL-MAKSOUD SAEEDAH MUSAED ALMUTAIRI AYMAN MUBARAK MOHAMMED AUFY WAEL ALTURAIKI ABDULAZIZ J.ALSHALANI AYMAN M.MAHMOUD CHEN LI 《Oncology Research》 SCIE 2023年第5期819-831,共13页
N6-methyladenosine methylation(m6A)is a common type of epigenetic alteration that prominently affects the prognosis of tumor patients.However,it is unknown how the m6A regulator affects the tumor microenvironment(TME)... N6-methyladenosine methylation(m6A)is a common type of epigenetic alteration that prominently affects the prognosis of tumor patients.However,it is unknown how the m6A regulator affects the tumor microenvironment(TME)cell infiltration in adrenocortical carcinoma(ACC)and how it affects the prognosis of ACC patients yet.The m6A alteration patterns of 112 ACC patients were evaluated,furthermore,the association with immune infiltration cell features was investigated.The unsupervised clustering method was applied to typify the m6A alteration patterns of ACC patients.The principal component analysis(PCA)technique was taken to create the m6A score to assess the alteration pattern in specific malignancies.We found two independent patterns of m6A alteration in ACC patients.The TME cell infiltration features were significantly in accordance with phenotypes of tumor immune-inflamed and immune desert in both patterns.The m6Ascore also served as an independent predictive factor in ACC patients.The somatic copy number variation(CNV)and patients prognosis can be predicted by m6A alteration patterns.Moreover,the ACC patients with high m6A scores had better overall survival(OS)and higher efficiency in immune checkpoint blockade therapy.Our work demonstrated the significance of m6A alteration to the ACC patients immunotherapy.The individual m6A alteration patterns analysis might contribute to ACC patients prognosis prediction and immunotherapy choice. 展开更多
关键词 m6A Tumor microenvironment Adrenocortical carcinoma IMMUNOTHERAPY PROGNOSIS
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Hirshfeld Surface Analysis for Investigation of Intermolecular Interaction of Molecular Crystals
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作者 Shintaro Suda Atsunobu Tateno +1 位作者 Daisuke Nakane Takashiro Akitsu 《International Journal of Organic Chemistry》 2023年第2期57-85,共29页
Hirshfeld surface analysis has been widely used in recent years as a means to quantify and visualize various types of intermolecular interactions in molecular crystals. This review article introduces intermolecular in... Hirshfeld surface analysis has been widely used in recent years as a means to quantify and visualize various types of intermolecular interactions in molecular crystals. This review article introduces intermolecular interactions discussed with Hirshfeld surface analysis and 2D fingerprint plots. In addition, using CIF files obtained from our previous results, Hirshfeld surface analysis was newly performed, and the resulting 3DHirshfeld surfaces, 2D print plots, molecular structural features, and crystal structure relationships were described. Classification of their intermolecular interactions, statistical discussion focused on crystalline water and perspective on ligand-protein docking are also mentioned. 展开更多
关键词 Chemical Crystallography Cambridge Structure Database CIF Hirshfeld Surface Analysis Schiff Base
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Involvement of Dectin-2 in the Innate Inflammatory Response Triggered by Influenza Virus Hemagglutinin
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作者 Hideki Yamamoto Chikako Tomiyama +3 位作者 Sho Yamasaki Shinobu Saijo Yoichiro Iwakura Kazuyoshi Kawakami 《Advances in Infectious Diseases》 2023年第3期478-497,共20页
C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed ana... C-type lectin receptors (CLRs) are representative pattern recognition receptors that recognize microbial polysaccharides expressed on antigen-presenting cells. In the present study, we carried out further detailed analysis on the involvement of Dectin-2, a CLR that senses high mannose polysaccharide, in innate immune responses induced by influenza virus hemagglutinin (HA). Treatment of HA with periodate or PNGase F induced lower interleukin (IL)-12p40 secretion by conventional dendritic cells (DCs) compared with the untreated group. In contrast, treatment with O-glycosidase did not affect cytokine production. Green fluorescent protein expression in canonical Dectin-2-transducing cells was approximately 3% - 12% following HA stimulation, except with the A/H1N1pdm09 subtype HA. This expression was markedly reduced in cells possessing mutated amino acids in the carbohydrate recognition domain of Dectin-2, especially following stimulation with HA derived from the A/H3N2 subtype. Interferon (IFN)-α production from CD11c<sup>+</sup>Siglec-H<sup>+</sup>PDCA-1<sup>+</sup> plasmacytoid DCs was significantly increased in Dectin-2 knockout mice compared with wild-type mice upon stimulation with HA except for the B/Yamagata lineage HA. These results suggested that Dectin-2 is involved in initiating inflammatory responses via mannose polysaccharide on HA. However, other mechanisms may function in the antiviral response, including the type I IFN axis. 展开更多
关键词 C-Type Lectin Receptors Influenza Virus Innate Immunity Type I Interferon
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Synthesis and Conductivity Characterization of Anti-Perovskite Na3OX Solid Electrolytes for All Solid Na-Ion Batteries
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作者 Wei Shi Masataka Ohta +3 位作者 Hiroaki Asakawa Yuki Osaki Mariko Murayama Xinwei Zhao 《Optics and Photonics Journal》 2023年第7期189-198,共10页
Solid electrolytes for all solid sodium-ion batteries have been attracting much attention as an alternative energy storage system, which have the advantage of being extremely safe because it can be charged quickly and... Solid electrolytes for all solid sodium-ion batteries have been attracting much attention as an alternative energy storage system, which have the advantage of being extremely safe because it can be charged quickly and is nonflammable. We have synthesized anti-perovskite type Na<sub>3</sub>OX (X = Br, and I) electrolytes with high purity, by reactions of halogen mixtures with sodium oxides. After mixing, it was filled in an alumina crucible and heated for 6 hours at 330°C. It was confirmed that a large crystal strain was introduced by eutectication, which might reduce the activation energy of Na ion conduction and lead to an improvement of the conductivity. A relatively higher ionic conductivity of σ = 1.55 × 10<sup>-7</sup> S/cm at 60°C has been obtained for Na<sub>3</sub>OBr<sub>0.6</sub>I<sub>0.4</sub>, which is about three orders higher than that in literature. A different ratio of X (X = Br, I) ions was added into sodium oxide to make the Na<sub>3</sub>OX crystal. The influence of strain introduction on optimizing the bottleneck and improving the conductivity was discussed. 展开更多
关键词 Sodium Ion Battery Solid Electrolyte Ionic Conductivity Anti-Perovskite
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Time/Space and Inertial System Reconsidered Based on the Adaptive Dynamical View
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作者 Tadashi Ando Ichiro Yamato 《Journal of Modern Physics》 2024年第11期1621-1631,共11页
We have succeeded in 2-slit interference simulation by assuming that a travelling particle interacts with its environment, getting information on the environmental condition according to the adaptive dynamics by Ohya,... We have succeeded in 2-slit interference simulation by assuming that a travelling particle interacts with its environment, getting information on the environmental condition according to the adaptive dynamics by Ohya, thus proposed the possibility that the entanglement comes from the interaction with the environment (Ando et al., 2023). This concept means that there should be no isolated or inertial system other than our unique universe space. Taking this message into account and assuming that the signal velocity is constant against our unique universe space, we reconsidered the inertial system and relativity theory by Galilei and Einstein and found several misunderstandings and errors. Time delay and Lorentz shrinkage were derived similarly to the prediction by special relativity theory, but Lorentz transformation and 4-dimensional time/space view were not. They must have implicitly and unconsciously assumed that any signals transfer information without giving any influences to any systems different from our adaptive dynamical view. We propose that their relativity theories should be reinterpreted in view of adaptive dynamics. 展开更多
关键词 Relativity Theory Inertial System Adaptive Dynamics INTERCONNECTION
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Annealing Temperature-Dependent Luminescence Color Coordination in Eu-Doped AlN Thin Films
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作者 Yingda Qian Mariko Murayama +1 位作者 Sujun Guan Xinwei Zhao 《Journal of Materials Science and Chemical Engineering》 2024年第1期20-28,共9页
AlN was used as a host material and doped with Eu grown on Si substrate by pulsed laser deposition (PLD) with low substrate temperature. The X-ray diffraction (XRD) data revealed the orientation and the composition of... AlN was used as a host material and doped with Eu grown on Si substrate by pulsed laser deposition (PLD) with low substrate temperature. The X-ray diffraction (XRD) data revealed the orientation and the composition of the thin film. The surface morphology was studied by scanning electron microscope (SEM). While raising the annealing temperatures from 300˚C to 900˚C, the emission was observed from AlN: Eu under excitation of 260 nm excitation. The photoluminescence (PL) was integrated over the visible light wavelength shifted from the blue to the red zone in the CIE 1931 chromaticity coordinates. The luminescence color coordination of AlN: Eu depending on the annealing temperatures guides the further study of Eu-doped nitrides manufacturing on white light emitting diode (LED) and full color LED devices. 展开更多
关键词 Low-Temperature PLD Growth Eu-Doped AlN Thin Film White Light Emitting Diode
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Effects of crystallinity, {001}/{101} ratio, and Au decoration on the photocatalytic activity of anatase TiO_2 crystals 被引量:7
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作者 Jiangyan Wang Baoshun Liu Kazuya Nakata 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期403-412,共10页
Anatase TiO2 nanocrystals and sub-microcrystals with truncated octahedral bipyramidal morphologies were prepared by direct calcination of TiOF2 precursors. The as-prepared TiO2 samples were thoroughly characterized by... Anatase TiO2 nanocrystals and sub-microcrystals with truncated octahedral bipyramidal morphologies were prepared by direct calcination of TiOF2 precursors. The as-prepared TiO2 samples were thoroughly characterized by X-ray diffraction, Raman spectroscopy, field-emission scanning electron microscopy, N2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and UV-visible diffuse spectroscopy. It was found that the crystallinity, grain size, and {001}/{101} ratio of the samples can be increased by raising the calcination temperature from 500 to 800℃. The higher crystallinity and {001}/{101} facet ratio resulted in an increase in both aqueous and gas-phase photocatalytic activities, by inhibiting the recombination and separation of electrons and holes. After selecting two TiO2 samples with high crystallinity and {001}/{101} ratio, Au nanoparticles were decorated on their surfaces, and the photocatalytic activity of the resulting samples under visible light illumination was studied. It was found that the visible light-induced photocatalytic activity increased by 2.6 and 4.8 times, respectively, upon Au decoration of the samples prepared by calcination of TiOF2 at 700 and 800℃. 展开更多
关键词 High crystallinity Anatase TiO2 High energy facets Au decoration Photocatalysis
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Prevention of esophageal strictures after endoscopic submucosal dissection 被引量:13
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作者 Shinichiro Kobayashi Nobuo Kanai +10 位作者 Takeshi Ohki Ryo Takagi Naoyuki Yamaguchi Hajime Isomoto Yoshiyuki Kasai Takahiro Hosoi Kazuhiko Nakao Susumu Eguchi Masakazu Yamamoto Masayuki Yamato Teruo Okano 《World Journal of Gastroenterology》 SCIE CAS 2014年第41期15098-15109,共12页
Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma an... Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma and dysplasia of Barrett&#x02019;s esophagus. However, the large defects in the esophageal mucosa often cause severe esophageal strictures, which dramatically reduce the patient&#x02019;s quality of life. Although preventive endoscopic balloon dilatation can reduce dysphagia and the frequency of dilatation, other approaches are necessary to prevent esophageal strictures after ESD. This review describes several strategies for preventing esophageal strictures after ESD, with a particular focus on anti-inflammatory and tissue engineering approaches. The local injection of triamcinolone acetonide and other systemic steroid therapies are frequently used to prevent esophageal strictures after ESD. Tissue engineering approaches for preventing esophageal strictures have recently been applied in basic research studies. Scaffolds with temporary stents have been applied in five cases, and this technique has been shown to be safe and is anticipated to prevent esophageal strictures. Fabricated autologous oral mucosal epithelial cell sheets to cover the defective mucosa similarly to how commercially available skin products fabricated from epidermal cells are used for skin defects or in cases of intractable ulcers. Fabricated autologous oral-mucosal-epithelial cell sheets have already been shown to be safe. 展开更多
关键词 Endoscopic submucosal dissection Esophageal stricture Systemic steroid therapy Autologous oral mucosal epithelial cell sheet
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Adaptive Learning with Large Variability of Teaching Signals for Neural Networks and Its Application to Motion Control of an Industrial Robot 被引量:2
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作者 Fusaomi Nagata Keigo Watanabe 《International Journal of Automation and computing》 EI 2011年第1期54-61,共8页
Recently, various control methods represented by proportional-integral-derivative (PID) control are used for robotic control. To cope with the requirements for high response and precision, advanced feedforward contr... Recently, various control methods represented by proportional-integral-derivative (PID) control are used for robotic control. To cope with the requirements for high response and precision, advanced feedforward controllers such as gravity compensator, Coriolis/centrifugal force compensator and friction compensators have been built in the controller. Generally, it causes heavy computational load when calculating the compensating value within a short sampling period. In this paper, integrated recurrent neural networks are applied as a feedforward controller for PUMA560 manipulator. The feedforward controller works instead of gravity and Coriolis/centrifugal force compensators. In the learning process of the neural network by using back propagation algorithm, the learning coefficient and gain of sigmoid function are tuned intuitively and empirically according to teaching signals. The tuning is complicated because it is being conducted by trial and error. Especially, when the scale of teaching signal is large, the problem becomes crucial. To cope with the problem which concerns the learning performance, a simple and adaptive learning technique for large scale teaching signals is proposed. The learning techniques and control effectiveness are evaluated through simulations using the dynamic model of PUMA560 manipulator. 展开更多
关键词 Neural networks large-scale teaching signal sigmoid function adaptive learning servo system PUMA560 manipulator trajectory following control nonlinear control.
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Brownian Dynamics Simulation of Microstructures and Elongational Viscosities of Micellar Surfactant Solution 被引量:3
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作者 魏进家 KAWAGUCHI Yasuo +1 位作者 宇波 李凤臣 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第12期4469-4472,共4页
Brownian dynamics simulation is conducted for a dilute surfactant solution under a steady uniaxial elongational flow. A new inter-cluster potential is used for the interaction among surfactant micelles to determine th... Brownian dynamics simulation is conducted for a dilute surfactant solution under a steady uniaxial elongational flow. A new inter-cluster potential is used for the interaction among surfactant micelles to determine the micellar network structures in the surfactant solution. The micellar network is successfully simulated. It is formed at low elongation rates and destroyed by high elongation rates. The computed elongational viscosities show elongation- thinning characteristics. The relationship between the elongational viscosities and the mierostructure of the surfactant solution is revealed. 展开更多
关键词 field emission molybdenum dioxide enhancement factor
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A Study on Development of a Hybrid Aerial/Terrestrial Robot System for Avoiding Ground Obstacles by Flight 被引量:2
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作者 Chinthaka Premachandra Masahiro Otsuka +2 位作者 Ryo Gohara Takao Ninomiya Kiyotaka Kato 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期327-336,共10页
To date, many studies related to robots have been performed around the world. Many of these studies have assumed operation at locations where entry is difficult, such as disaster sites, and have focused on various ter... To date, many studies related to robots have been performed around the world. Many of these studies have assumed operation at locations where entry is difficult, such as disaster sites, and have focused on various terrestrial robots, such as snake-like, humanoid, spider-type, and wheeled units. Another area of active research in recent years has been aerial robots with small helicopters for operation indoors and outdoors. However,less research has been performed on robots that operate both on the ground and in the air. Accordingly, in this paper, we propose a hybrid aerial/terrestrial robot system. The proposed robot system was developed by equipping a quadcopter with a mechanism for ground movement. It does not use power dedicated to ground movement, and instead uses the flight mechanism of the quadcopter to achieve ground movement as well. Furthermore, we addressed the issue of obstacle avoidance as part of studies on autonomous control. Thus, we found that autonomous control of ground movement and flight was possible for the hybrid aerial/terrestrial robot system, as was autonomous obstacle avoidance by flight when an obstacle appeared during ground movement. 展开更多
关键词 GROUND movement/flight control HYBRID aerial/terrestrial robot OBSTACLE avoidance by FLIGHT OBSTACLE recognition
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Effect of herbal medicine Juzentaihoto on hepatic and intestinal heat shock gene expression requires intestinal microflora in mouse 被引量:5
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作者 Miho Kato Atsushi Ishige +7 位作者 Naoko Anjiki Masahiro Yamamoto Yoshifumi Irie Mitsue Taniyama Ryoko Kibe Junichiro Oka Yoshimi Benno Kenji Watanabe 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第16期2289-2297,共9页
AIM: To evaluate the role of intestinal microflora in the effects of multi-herbal medicine on gene expression in the gut and liver. METHODS: The multi-herbal medicine Juzentaihoto (JTX) was administered to five ge... AIM: To evaluate the role of intestinal microflora in the effects of multi-herbal medicine on gene expression in the gut and liver. METHODS: The multi-herbal medicine Juzentaihoto (JTX) was administered to five germ-free mice and regular mice for 2 wk. Among the results of the comprehensive gene chip analysis of the intestine and liver, we featured heat shock proteins (HSPs) 70 and 105 because their gene expression changed only in the presence of microflora. Real-time RT-PCR was performed to confirm the expression levels of these HSP genes. To determine whether JTX acts directly on the HSP genes, sodium arsenite (SA) was used to induce the heat shock proteins directly. To examine the change of the intestinal microflora with administration of JTX, the terminal restriction fragment polymorphism (T-RFLP) method was used. To identify the changed bacteria, DNA sequencing was performed.documented by gene chip and real-time RT-PCR, changed with the administration of JTX in the regular mice but not in the germ-free mice. JTX did not suppress the direct induction of the HSPs by SA. T-RFLP suggested that JTX decreased unculturable bacteria and increased Lactobacillus johnsoni. These data suggested that JTX changed the intestinal microflora which, in turn, changed HSP gene expression.CONCLUSION: Intestinal microflora affects multi-herbal product JTX on the gene expression in the gut and liver. 展开更多
关键词 Herbal medicine Juzentaihoto Intestinal microflora Terminal restriction fragment length polymorphism Heat shock protein
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Fracture of thermal barrier coating with multiple surface cracks and delaminations:Interlayer effect 被引量:1
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作者 范学领 许荣 M.Kikuchi 《Journal of Central South University》 SCIE EI CAS 2014年第7期2579-2583,共5页
Multiple surface cracks and interfacial delamination are the major failure mechanisms in film/substrate systems.The effect of interlayer upon the failure mechanisms of interfacial delamination concomitant to surface c... Multiple surface cracks and interfacial delamination are the major failure mechanisms in film/substrate systems.The effect of interlayer upon the failure mechanisms of interfacial delamination concomitant to surface crack was explored.Finite element model was developed to obtain the stress and energy release rate(ERR),which governs the propagation of interface cracks.The dependences of delamination upon the geometry and constitutive properties of interlayer were examined.The results indicate that the effect of elastic modulus of interlayer on the steady state ERR is insignificant.In cases of different geometrical parameters,however,the steady ERR decreases with the increase of the interlayer thickness.These findings lead to the conclusion that the interlayer constraint has significant effect on the ERR and thus coating life,which can be adopted to modify the ceramic top coat. 展开更多
关键词 thermal barrier coating DELAMINATION INTERLAYER energy release rate
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Enhanced hepatic differentiation in the subpopulation of human amniotic stem cells under 3D multicellular microenvironment 被引量:3
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作者 Kinji Furuya Yun-Wen Zheng +11 位作者 Daisuke Sako Kenichi Iwasaki Dong-Xu Zheng Jian-Yun Ge Li-Ping Liu Tomoaki Furuta Kazunori Akimoto Hiroya Yagi Hiromi Hamada Hiroko Isoda Tatsuya Oda Nobuhiro Ohkohchi 《World Journal of Stem Cells》 SCIE 2019年第9期705-721,共17页
BACKGROUND To solve the problem of liver transplantation donor insufficiency,an alternative cell transplantation therapy was investigated.We focused on amniotic epithelial cells(AECs)as a cell source because,unlike in... BACKGROUND To solve the problem of liver transplantation donor insufficiency,an alternative cell transplantation therapy was investigated.We focused on amniotic epithelial cells(AECs)as a cell source because,unlike induced pluripotent stem cells,they are cost-effective and non-tumorigenic.The utilization of AECs in regenerative medicine,however,is in its infancy.A general profile for AECs has not been comprehensively analyzed.Moreover,no hepatic differentiation protocol for AECs has yet been established.To this end,we independently compiled human AEC libraries,purified amniotic stem cells(ASCs),and co-cultured them with mesenchymal stem cells(MSCs)and human umbilical vein endothelial cell(HUVECs)in a 3D system which induces functional hepatic organoids.AIM To characterize AECs and generate functional hepatic organoids from ASCs and other somatic stem cells METHODS AECs,MSCs,and HUVECs were isolated from the placentae and umbilical cords of cesarean section patients.Amnion and primary AEC stemness characteristics and heterogeneity were analyzed by immunocytochemistry,Alkaline phosphatase(AP)staining,and flow cytometry.An adherent AEC subpopulation was selected and evaluated for ASC purification quality by a colony formation assay.AEC transcriptomes were compared with those for other hepatocytes cell sources by bioinformatics.The 2D and 3D culture were compared by relative gene expression using several differentiation protocols.ASCs,MSCs,and HUVECs were combined in a 3D co-culture system to generate hepatic organoids whose structure was compared with a 3D AEC sphere and whose function was elucidated by immunofluorescence imaging,periodic acid Schiff,and an indocyanine green(ICG)test.RESULTS AECs have certain stemness markers such as EPCAM,SSEA4,and E-cadherin.One AEC subpopulation was also either positive for AP staining or expressed the TRA-1-60 and TRA-1-81 stemness markers.Moreover,it could form colonies and its frequency was enhanced ten-fold in the adherent subpopulation after selective primary passage.Bioinformatics analysis of ribose nucleic acid sequencing revealed that the total AEC gene expression was distant from those of pluripotent stem cells and hepatocytes but some gene expression overlapped among these cells.TJP1,associated with epidermal growth factor receptor,and MET,associated with hepatocyte growth factor receptor,were upregulated and may be important for hepatic differentiation.In conventional flat culture,the cells turned unviable and did not readily differentiate into hepatocytes.In 3D culture,however,hepatic gene expression of the AEC sphere was elevated even under a two-step differentiation protocol.Furthermore,the organoids derived from the MSC and HUVEC co-culture showed 3D structure with polarity,hepatic-like glycogen storage,and ICG absorption/elimination.CONCLUSION Human amniotic epithelial cells are heterogeneous and certain subpopulations have high stemness.Under a 3D co-culture system,functional hepatic organoids were generated in a multicellular microenvironment. 展开更多
关键词 3D MICROPATTERN Amniotic epithelial CELLS Amniotic STEM CELLS Hepatic differentiation Heterogeneity HUMAN PLACENTAL tissue HUMAN umbilical vein endothelial CELLS Mesenchymal STEM CELLS Multicellular microenvironment Organoid
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Development of flexible telescopic boom model using ANCF sliding joint constraints with LuGre friction 被引量:1
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作者 Hiroki Fujita Hiroyuki Sugiyama 《Theoretical & Applied Mechanics Letters》 CAS 2012年第6期37-42,共6页
In this investigation, a modeling procedure of a telescopic boom of cranes is developed using the absolute nodal coordinate formulation together with the sliding joint constraints. Since telescopic booms are extracted... In this investigation, a modeling procedure of a telescopic boom of cranes is developed using the absolute nodal coordinate formulation together with the sliding joint constraints. Since telescopic booms are extracted and retracted under various operating conditions, the overall length of the boom changes dynamically, leading to the time-variant vibration characteristics. For modeling the telescopic structure of booms, a special care needs to be exercised since the location of the sliding contact point moves Mong the deformable axis of the flexible boom and the solution to a moving boundary problem is required. This issue indeed makes the modeling of the telescopic boom difficult, despite the significant needs for the analysis. It is, therefore, the objective of this investigation to develop a modeling procedure for the flexible telescopic boom by considering the sliding contact condition with the dynamic frictional effect. To this end, the sliding joint constraint developed for the absolute nodal coordinate formulation is employed for describing relative sliding motion between flexible booms, while flexible booms are modeled using the beam element of the absolute nodal coordinate formulation, which allows for modeling the large rotation and deformation of the structure. 展开更多
关键词 telescopic boom sliding joint flexible multibody dynamics absolute nodal coordinateformulation
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Flexural rigidity of honeycomb consisting of hexagonal cells 被引量:3
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作者 Dai-Heng Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期840-844,共5页
In this study,the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated.It is found that the honeycomb bending can not be evaluated by using the equivalent elastic moduli obtained from... In this study,the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated.It is found that the honeycomb bending can not be evaluated by using the equivalent elastic moduli obtained from the in-plane deformation because the moments acting on the inclined cell wall are different for in-plane deformation and bending deformation.Based on the fact that the inclined wall is twisted under the condition of the rotation angle in both connection edges being zero,a theoretical technique for calculating the flexural rigidity of honeycombs is proposed,and the validity of the present analysis is demonstrated by numerical results obtained by BFM. 展开更多
关键词 Honeycomb · Flexural rigidity · Equivalent elastic modulus · Bending · Elasticity
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Computational Study on UV-Vis and CD Spectra of Chiral Schiff Base Ni(ll), Cu(ll) and Zn(ll) Complexes for Discussion of Induced CD 被引量:1
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作者 Chigusa Kominato Takashiro Akitsu 《Journal of Chemistry and Chemical Engineering》 2012年第11期957-961,共5页
Simulated UV-vis and CD (circular dichroism) spectra were obtained for several chiral Schiff base Ni(II), Cu(II) and Zn(II) complexes by TD-DFT (time dependent-density functional theory)and Z1NDO calculation... Simulated UV-vis and CD (circular dichroism) spectra were obtained for several chiral Schiff base Ni(II), Cu(II) and Zn(II) complexes by TD-DFT (time dependent-density functional theory)and Z1NDO calculations. Dipole moments for them were also evaluated by ZINDO calculations and revealed that Cu(II) complexes exhibited the largest values than the analogous Ni(II) and Zn(II) complexes. Although these complexes possessed large dipole moments, induced CD by these complexes were observed a Cu(II)-containing metallodendrimer nor Cu-nanoclusters prepared in a PAMAM (polyamidoamine) dendrimer experimentally nevertheless of other related chiral Schiff base Ni(II), Cu(II), and Zn(II) complexes. The present results suggested that steric factors of ligands were more important than electronic factors for emerging induced CD bands by supramolecular interactions. 展开更多
关键词 锌(Ⅱ)配合物 SCHIFF碱 CD光谱 镍(Ⅱ) 铜(Ⅱ) UV-VIS 手性 计算
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