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91.
Polymer electrolytes based on poly(ethylene oxide) and lithium salts have been widely studied in recent years. In order to enhance the room temperature ionic conductivity of PEO-LiX complexes, various techniques, such as addition of plasticizers and crown ether, and also irradiation by γ and electron beams have been investigated. The enhancement of the conductivity by irradiation has been accounted for the decreasing of the crystallinity of PEO-LiX. We reviewed these results and have investigated the degradation processes of PEO using Tb3+ fluorescence probes. We have also studied on the effects of irradiation of polymers such as poly(acrylic acid) (PAA), poly(methacrylic acid) (PMA) and PEO using Tb+3 fluorescence probe. Various monomers containing SO3H and COOH have been grafted on poly(ethylene oxide) using irradiation technique. The structures and ionic conductivities of Li and Na salts of irradiated products were investigated in detail. 相似文献
92.
Ashish Kaul Raviprasad Kuthethur Yoshiyuki Ishida Keiji Terao Renu Wadhwa Sunil C. Kaul 《Molecules (Basel, Switzerland)》2022,27(1)
Propolis, also known as bee-glue, is a resinous substance produced by honeybees from materials collected from plants they visit. It contains mixtures of wax and bee enzymes and is used by bees as a building material in their hives and by humans for different purposes in traditional healthcare practices. Although the composition of propolis has been shown to depend on its geographic location, climatic zone, and local flora; two largely studied types of propolis: (i) New Zealand and (ii) Brazilian green propolis have been shown to possess Caffeic Acid Phenethyl Ester (CAPE) and Artepillin C (ARC) as the main bioactive constituents, respectively. We have earlier reported that CAPE and ARC possess anticancer activities, mediated by abrogation of mortalin-p53 complex and reactivation of p53 tumor suppressor function. Like CAPE, Artepillin C (ARC) and the supercritical extract of green propolis (GPSE) showed potent anticancer activity. In this study, we recruited low doses of GPSE and ARC (that did not affect either cancer cell proliferation or migration) to investigate their antistress potential using in vitro cell based assays. We report that both GPSE and ARC have the capability to disaggregate metal- and heat-induced aggregated proteins. Metal-induced aggregation of GFP was reduced by fourfold in GPSE- as well as ARC-treated cells. Similarly, whereas heat-induced misfolding of luciferase protein showed 80% loss of activity, the cells treated with either GPSE or ARC showed 60–80% recovery. Furthermore, we demonstrate their pro-hypoxia (marked by the upregulation of HIF-1α) and neuro-differentiation (marked by differentiation morphology and upregulation of expression of GFAP, β-tubulin III, and MAP2). Both GPSE and ARC also offered significant protection against oxidative stress and, hence, may be useful in the treatment of old age-related brain pathologies. 相似文献
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A high‐performance liquid chromatography assay with a triazole‐bonded column for evaluation of d‐amino acid oxidase activity
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Megumi Iwasaki Yoshiyuki Kashiwaguma Chihiro Nagashima Mao Izumi Ayano Uekusa Sumiko Iwasa Mayu Onozato Hideaki Ichiba Takeshi Fukushima 《Biomedical chromatography : BMC》2016,30(3):384-389
Elution profiles of kynurenic acid (KYNA) and 7‐chlorokynurenic acid (Cl‐KYNA) were examined by high‐performance liquid chromatography (HPLC) using a triazole‐bonded stationary phase column (Cosmosil® HILIC) under isocratic elution of a mobile phase consisting of CH3CN–aqueous 10 mm ammonium formate between pH 3.0 and 6.0. The capacity factors of KYNA and Cl‐KYNA varied with both the CH3CN content and the pH of the mobile phase. The elution order of KYNA and Cl‐KYNA was reversed between the CH3CN‐ and H2O‐rich mobile phases, suggesting that hydrophilic interactions and anion‐exchange interactions caused retention of KYNA and Cl‐KYNA in the CH3CN‐ and H2O‐rich mobile phases, respectively. The present HPLC method using a triazole‐bonded column and fluorescence detection (excitation 250 nm, emission 398 nm) was applied to monitor in vitro production of KYNA from d ‐kynurenine (d ‐KYN) by d ‐amino acid oxidase (DAO) using Cl‐KYNA as an internal standard. A single KYNA peak was clearly observed after enzymatic reaction of d ‐KYN with DAO. Production of KYNA from d ‐KYN was suppressed by the addition of commercial DAO inhibitors. The present HPLC method can be used to evaluate DAO activity and DAO inhibitory effects in candidate drugs for the treatment of schizophrenia. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
97.
Yoshiyuki Koyano Norio Takenaka Yukinori Nakagawa Masataka Nagaoka 《Journal of computational chemistry》2010,31(14):2628-2641
98.
Yoshiyuki Kawashima Tsuyoshi Usami G. Yu. Golubiatnikov Eizi Hirota 《Journal of Molecular Spectroscopy》2010,263(1):11-20
Rotational spectra of both trans and cis forms of the N-methylformamide normal as well as deuterated (HCONDCH3, referred to as N-D) species were observed by Fourier transform microwave spectroscopy in the frequency region from 5 to 118 GHz. Samples were prepared in the form of a beam by a pulsed jet valve maintained at 50 °C and were introduced in a high-vacuum cavity cell, with either Ne or Ar as a carrier gas at a backing pressure of 100 kPa. The observed spectra were analyzed to yield molecular parameters including rotational constants and barrier, V3, to CH3 internal-rotation: 53.9 (6) and 301 (4) cm−1 for the trans and cis forms of the normal species, respectively, and 41.9 (6) and 309 (4) cm−1 for the trans and cis forms of the N-D species, respectively. Spectra of four trans isotopologues with 13C, 15N, or 18O singly-substituted in the internal-rotation A state were observed and analyzed to derive the rs structure of the trans form. For comparison with the experimental data, ab initio calculations were carried out at MP2/6-31G∗∗ level to derive molecular structure, potential barrier to CH3 internal rotation, and the energy difference between the cis and trans forms. An extensive coupling was found between the CH3 internal rotation and N-H out-of-plane bending, suggesting that the potential function for the CH3 internal-rotation deviates considerably from a simple cos(3α) form. The effects of the V6 term is briefly discussed. 相似文献
99.
Yoshiyuki Shirakawa Yusuke Hayashi Kazunori Kadota Hiroshi Mio Hiroto Ohtsuki Atsuko Shimosaka Jusuke Hidaka 《Journal of nanoparticle research》2008,10(4):577-584
In our previous paper, structural changes of selenium powders ground by a planetary ball mill at various rotational speeds
were investigated for the nanostructural modification of particles using mechanical grinding process. The experimental results
indicated that the amorphisation of Se by grinding accompanies lattice strain, and the lattice strain arises from impact energy
which is more than an energy related to intermolecular interaction. In this paper, molecular dynamics simulations of selenium
have been carried out under compressing conditions of various pressure strengths for obtaining information of the lattice
strain at atomic level. Then, dynamical behaviour of atomic configuration has been discussed in this process. The structural
disordering and formation of the structural defects were estimated by deviations of bond length and angle and the number of
created defects before and after compressing from simulated results. The disordering took place during compressing at various
pressure strengths, and the disordered atoms return to their initial positions at lower pressure. Stable disordered state
and defects after the compression can however remain by compression at more than a certain pressure strength mainly associated
with binding energy of selenium. 相似文献
100.