检索结果-南通市图书馆

Rebuilding insight into the pathophysiology of Alzheimer’s disease through new blood-brain barrier models

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第9期19卷 1954-1960页

作者： Kinya matsuo Hideaki Nshihara Yamaguchi University Graduate School of Medicine YamaguchiJapan Department of Neurotherapeutics Yamaguchi UniversityUbeJapan

The blood-brain barrier is a unique function of the microvasculature in the brain parenchyma that maintains homeostasis in the central nervous ***-brain barrier breakdown is a common pathology in various neurological diseases,such as Alzheimer’s disease,stroke,multiple sclerosis,and Parkinson’s ***,it has been considered a consequence of neuroinflammation or neurodegeneration,but recent advanced imaging techniques and detailed studies in animal models show that blood-brain barrier breakdown occurs early in the disease process and may precede neuronal ***,the blood-brain barrier is attractive as a potential therapeutic target for neurological diseases that lack effective *** elucidate the molecular mechanism underlying blood-brain barrier breakdown and translate them into therapeutic strategies for neurological diseases,there is a growing demand for experimental models of human origin that allow for functional ***,several human induced pluripotent stem cell-derived blood-brain barrier models have been established and various in vitro blood-brain barrier models using microdevices have been *** in the Alzheimer’s disease field,the human evidence for blood-brain barrier dysfunction has been demonstrated and human induced pluripotent stem cell-derived blood-brain barrier models have suggested the putative molecular mechanisms of pathological blood-brain *** this review,we summarize recent evidence of blood-brain barrier dysfunction in Alzheimer’s disease from pathological analyses,imaging studies,animal models,and stem cell ***,we discuss the potential future directions for blood-brain barrier research.

关键词： Alzheimer’s disease blood-brain barrier human induced pluripotent stem cells

Chitin Based Fuel Cell and Its Proton Conductivity

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2018年第10期9卷 779-789页

作者： Takashi Kawabata yasumitsu matsuo Department of Life Science Faculty of Science & Engineering Setsunan University Neyagawa Osaka Japan

We have fabricated a fuel cell based on the tissue-derived biomaterial “chitin”, and investigated its proton conductivity. It was found that chitin becomes the electrolyte of the fuel cell in the humidified condition, and power density of the fuel cell using chitin electrolyte becomes typically 1.35 mW/cm2 at the 100% relative humidity. This result is the first result showing that the polysaccharide obtained from nature becomes the fuel cell electrolyte. Moreover, this result indicates that chitin is proton conductor in the humidified condition. In the chitin sheet plane, proton conductivity in chitin is observed approximately 0.1 S/m. Further, it was also found that chitin has the anisotropic proton conductivity. The proton conductivity along the chitin fiber direction is higher than that perpendicular to the chitin fiber direction. From these results, it is deduced that the formation of water bridges accompanied by hydration plays an important role in the appearance of proton conductivity in chitin.

关键词： Fuel Cell Proton Conductor Electrolyte Biomaterials

Anomalous Proton Conductivity in Chitin-Chitosan Mixed Compounds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2020年第1期11卷 1-11页

作者： Takashi Kawabata Yusuke Takahashi yasumitsu matsuo Department of Life Science Faculty of Science & Engineering Setsunan University Ikeda-Nakamachi Neyagawa Osaka Japan

In order to investigate a key factor for the appearance of proton conductivity in chitin-chitosan mixed compounds, the chitin-chitosan mixed compounds (chitin)x(chitosan)1-x were prepared and these proton conductivities have been investigated. DC proton conductivity σ is obtained from Nyquist plot of impedance measurement data, and the relationship between σ and mixing ratio x has been made clear. It was found that the x dependence of σ is non-monotonous. That is, σ shows the anomalous behavior, and has peaks around x = 0.4 and 0.75. This result indicates that there exist optimal conditions for the realization of high-proton conductivity in the chitin-chitosan mixed compound in which the number of acetyl groups is different. From the FT-IR measurement, we have found that the behavior of proton conductivity in (chitin)x(chitosan)1-x is determined by the amount of water content changed by x. Using these results, proton conductivity, which is important for the application of conducting polymers in chitin-chitosan mixed compounds, will be able to be easily controlled by adjusting the mixing ratio x.

关键词： Chitin Chitosan Mixed Compounds Proton Conductor Biomaterial

Collagen-Based Fuel Cell and Its Proton Transfer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2017年第11期8卷 747-756页

作者： yasumitsu matsuo Hiroki Ikeda Takashi Kawabata Junko Hatori Hiroshi Oyama Department of Life Science Faculty of Science & Engineering Setsunan University Neyagawa Japan

We have fabricated the fuel cell based on the tissue derived biomaterial “collagen” and investigated its proton transfer. It was found that “collagen” becomes the electrolyte of fuel cell in the humidified condition. The power density of the fuel cell becomes typically 8.6 W/m2 in the 80% humidity. Further, these results indicate that collagen exhibits proton conductivity in the humidified condition. Both of proton conductivity and dielectric constant increase by the increase of humidity. From the analyses of the frequency dependence of AC conductivity, it was found that proton conductivity and the dielectric dispersion observed in the humidified condition are caused by the formation of the water bridge, which is bonded with the collagen peptide chain. Considering that hydration induces the formation of the water bridge and that increases proton conductivity and dielectric constant, it is deduced that proton transfer in the fuel cell based on collagen is caused by the breaking and rearrangement of hydrogen bond in the water bridge.

关键词： Fuel Cell Proton Conductor Electrolyte Biomaterials

Excellentπ-Bowl Semiconductors Based on C_(70)Subunit

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第2期6卷 353-364页

作者： Meng Chen Yuxiao Duan Xinyue Liu Qian Zhan Hironobu Hayashi Kyohei matsuo Hiroko Yamada Guangpeng Gao Yonghao Zheng Lei Zhang Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029 School of Optoelectronic Science and Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 610054 Division of Materials Science Nara Institute of Science and Technology(NAIST)IkomaNara 630-0192 Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081

As open substructures of fullerenes,aromaticπ-bowls are promising candidates as new organic semiconductors,as well as attractive hosts for *** demonstrate herein the synthesis and characterization of a novel C_(2v)symmetricπ-bowl,pyracyleno[6,5,4,3,2,1-pqrstuv]pentaphene(3).Bowl 3 was equipped with two distinctive reactive sites,allowing for bromination and cross-coupling reactions to readily yield functionalized bowls with two 2,4,6-trimethylphenyl(5)and triethylsilyl(TES)-ethynyl(6)substituents,***-temperature 1H NMR analysis and density functional theory(DFT)calculations indicated bowl-to-bowl inversions of 3,5,and 6 at room *** alternating the substituents,the crystal structures of the threeπ-bowls 3,5,and 6 could be controlled from 1D linear to 1D slipped to 2D herringbone packing motifs,providing insight into the packing behavior ofπ-bowls.1H NMR titration study indicated that the TES-ethynyl substituent enhanced the ability ofπ-bowl to bind C_(70)with an association constant of 2485 M−*** C_(70)molecules withπ-bowls 3 and 6 formed 1:1 complexes,in which C_(70)molecules aggregated into zig-zag and 1D linear arrays,*** hole mobility of 2.3 cm^(2)V^(−1)^s(−1)and electron mobility of 0.16 cm^(2)V^(−1)^s(−1)ofπ-bowl 3 and its complex with C_(70)were demonstrated,respectively,which proved a great value for the development of aromaticπ-bowl semiconductors with tunable properties for organic electronic devices.

关键词： organic semiconductor π-bowl fullerene crystal engineering mobility

Operationally Simple Enantioselective Silane Reduction of Ketones by the [Ir(OMe)(cod)]₂/Azolium Catalytic System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Organic Chemistry 2024年第1期14卷 1-19页

作者： Satoshi Sakaguchi Chika Nagao Ryo Ichihara Shogo matsuo Department of Chemistry and Materials Engineering Faculty of Chemistry Materials and Bioengineering Kansai University Suita Japan

An operationally simple protocol was designed for the enantioselective silane reduction (ESR) of ketones using air- and moisture-stable [Ir(OMe)(cod)]2 (cod = 1,5-cyclooctadiene) (3) as a metal catalyst precursor. This reaction was driven by chiral hydroxyamide-functionalized azolium salt 2. The catalytic ESR reaction could be performed under benchtop conditions at room temperature. Treatment of 2 with 3 in THF yielded the monodentate IrCl(NHC)(cod) (NHC = N-heterocyclic carbene) complex 4 in 93% yield, herein the anionic methoxy ligand of 3 serves as an internal base that deprotonates the azolium ring of 2. The well-defined Ir complex 4 catalyzed the ESR reaction of propiophenone (6) with (EtO)2MeSiH using the pre-mixing reaction procedure. Based on this success, the catalytic ESR reaction was designed and implemented using an in situ-generated NHC/Ir catalyst derived from 2 and 3. Thus, a wide variety of aryl ketones could be reduced to the corresponding optically active alcohols in moderate to excellent stereoselectivities at room temperature without temperature control. Since the high catalytic activity of 3 was observed, we next evaluated several other transition metal catalyst precursors for the catalytic ESR reaction under the influence of 2. This evaluation revealed that Ir(acac)(cod) (acac = acetylacetonate) (28) and [IrCl(cod)]2 (5) can be successfully used as metal catalyst precursors in the ESR reaction.

关键词： Asymmetric Catalysis Enantioselective Reduction Hydrosilylation Reaction N-Heterocyclic Carbene Iridium

Electroencephalogram Signal Correlations between Default Mode Network and Attentional Functioning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Behavioral and Brain Science 2024年第4期14卷 119-134页

作者： Moemi matsuo Takashi Higuchi Toranosuke Abe Takuya Ishibashi Ayano Egashira Rio Kamashita Faculty of Rehabilitation Sciences Nishi Kyushu University Kanzaki Japan Department of Physical Therapy Osaka University of Human Sciences Settsu Japan Research Center for Child Mental Development Chiba University Chiba Japan

Attentional issues may affect acquiring new information, task performance, and learning. Cortical network activities change during different functional brain states, including the default mode network (DMN) and attention network. We investigated the neural mechanisms underlying attentional functions and correlations between DMN connectivity and attentional function using the Trail-Making Test (TMT)-A and -B. Electroencephalography recordings were performed by placing 19 scalp electrodes per the 10 - 20 system. The mean power level was calculated for each rest and task condition. Non-parametric Spearman’s rank correlation was used to examine the correlation in power levels between the rest and TMT conditions. The most significant correlations during TMT-A were observed in the high gamma wave, followed by theta and beta waves, indicating that most correlations were in the parietal lobe, followed by the frontal, central, and temporal lobes. The most significant correlations during TMT-B were observed in the beta wave, followed by the high and low gamma waves, indicating that most correlations were in the temporal lobe, followed by the parietal, frontal, and central lobes. Frontoparietal beta and gamma waves in the DMN may represent attentional functions.

关键词： Cortical Network Activities Electroencephalography Attention Default Mode Network

Enhancement of Visual Attention by Color Revealed Using Electroencephalography

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Therapy and Rehabilitation 2024年第1期12卷 1-9页

作者： Moemi matsuo Takashi Higuchi Takuya Ishibashi Ayano Egashira Toranosuke Abe Hiroya Miyabara Faculty of Rehabilitation Sciences Nishikyushu University Kanzaki Japan Department of Physical Therapy Osaka University of Human Sciences Settsu Japan

Attention constitutes a fundamental psychological feature guiding our mental effort toward specific objects, concurrent with processes such as memory, reasoning, and imagination. Visual attention, crucial for selecting surrounding information, often decreases in older adults and patients with cerebrovascular disorders. Effective methods to enhance attention are scarce. Here, we investigated whether color information influences visual attention and brain activity during task performance, utilizing EEG. We examined 13 healthy young adults (seven women and six men;mean age: 21.2 ± 0.58 years) using 19-electrode electroencephalograms to assess the impact of color information on visual attention. The Clinical Assessment for Attention cancellation test was conducted under the black, red, and blue color conditions. Wilcoxon’s signed-rank test was used to assess differences in task performance (task time and error) between conditions. Spearman’s rank correlation was utilized to examine the correlation in power levels between task performance and color conditions. Significant variations in total task errors were observed among color conditions. The black condition exhibited the highest error frequency (0.7 ± 0.9 times), followed by the red condition (0.5 ± 0.8 times), with the lowest error frequency occurring in the blue (0.2 ± 0.4 times) condition (black vs. red: P = 0.03;black vs. blue: P = 0.00;red vs. blue: P = 0.032). No time difference was observed. The black condition showed negative delta and high-gamma correlations in the central electrodes. The red condition revealed positive alpha and low-gamma correlations in the frontal and occipital areas. Although no correlations were observed in the blue condition, it enhanced attentional performance. Positive alpha and low-gamma waves might be crucial for spotting attentional errors in key areas. Our findings provide insights into the effects of color information on visual attention and potential neural correlates associated

关键词： Attention Higher Brain Function Electroencephalography Neuroimaging Rehabilitation

Flexible Förster resonance energy transfer-assisted optical waveguide based on elastic mixed molecular crystals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aggregate

Aggregate 2023年第6期4卷 95-100页

作者： Takumi matsuo Koki Ikeda Shotaro Hayashi School of Engineering Science Kochi University of TechnologyKochiJapan

Flexible molecular crystal waveguides based on elastic molecular crystals(EMCs)are essential inﬂexible and compact optical *** increased loss coefﬁ-cientαdue to self-absorption is often a problem in optical waveguides(OWGs)ofﬂuorescent chemical materials waveguiding photons in active ***,the development of anthracene-based elastic mixed molecular crystals(EMMCs)is reported for Förster Resonance Energy Transfer(FRET)-assisted *** yield a FRET crystal system based on elastic molecular crystals,1%–5%accep-tor doping forﬂuorescent molecular crystals of 9,10-dibromoanthracene 1 was successful by selecting the same regioisomer having electron-withdrawing group,9,10-diformylanthracene 2,as a *** addition to conversion to the mixed system,there is a difference in the elastic modulus and hardness in EMC C1 and EMMC C2@***,the elastic behaviour was also shown in a few percent doping of the ***αvalue of this EMMC,composed of 1 including 1%of 2(0.0077 dB/μm),is much lower than that of EMC composed of 1(0.1258 dB/μm)because of reducing self-absorption in the FRET *** efﬁcient andﬂexible OWG was successfully developed by selecting an appropriate acceptor molecule and its low doping rate for mixed crystal *** method is a practical approach in various functional andﬂexible crystal systems.

关键词： anthracene elastic mixed molecular crystals ﬂexible Förster resonance energy transfer optical waveguide