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881.
Maneesri J Azuma M Sakai Y Igarashi K Matsumoto T Fukuda H Kondo A Ooshima H 《Journal of Bioscience and Bioengineering》2005,99(4):354-360
Most proteins involved in the synthesis of the GPI core structure of Saccharomyces cerevisiae are essential for growth. To explore the relationship between the GPI anchor structure and beta-1,6-glucan synthesis, we screened deletion mutants in genes involved in GPI synthesis for osmotic remedial growth. Heterozygous diploid strains were dissected on medium with osmotic support and slow growth of the mcd 4 deletion mutant was observed. The mcd 4 mutant showed abnormal morphology and cell aggregation, and was hypersensitive to SDS, hygromycin B and K1 killer toxin. Incorporation of GPI cell wall proteins was examined using a GPI-Flo 1 fusion protein. The result suggested that the mcd 4 deletion causes a decrease in GPI cell wall proteins levels. The mutation also caused a decrease in mannan levels and an increase in alkali-insoluble beta-1,6-glucan and chitin levels in the cell wall. 相似文献
882.
Hong-Baek Cho Son Thanh Nguyen Tadachika Nakayama Hisayuki Suematsu Tsuneo Suzuki Weihua Jiang Satoshi Tanaka Bum Sung Kim Koichi Niihara 《Acta Materialia》2012,60(20):7249-7257
Self-assemblies of nanodiamonds (NDs) were incorporated into polyepoxide-based composite films by electric field inducement. ND particles were dispersed by sonication in a prepolymer mixture of polyepoxide followed by high-speed mixing. The homogeneous suspension was cast onto a polyamide spacer and subjected to three different electric fields, AC, DC and switching DC, before the mixture became cross-linked. Analysis revealed that linearly aligned NDs (LANDs) were fabricated in the hybrid film, and the LANDs were aligned perpendicular to the film surface with high anisotropy. The nanohybrid films with assemblies of LANDs exhibited enhanced thermal conductivity with minimal decrease in the electrical insulation properties of the polyepoxide and are therefore attractive for application as thermal interface materials in the semiconductor industry. Mechanisms for the field-induced fabrication and structural variation of LANDs in the polymer matrix are elucidated in relation to enhancement of the physical properties. 相似文献
883.
Katsunori Matsushita Takumi Okuda Dr. Shohei Mori Dr. Masamitsu Konno Dr. Hidetoshi Eguchi Dr. Ayumu Asai Dr. Jun Koseki Dr. Yoshifumi Iwagami Dr. Daisaku Yamada Dr. Hirofumi Akita Dr. Tadafumi Asaoka Dr. Takehiro Noda Dr. Koichi Kawamoto Dr. Kunihito Gotoh Dr. Shogo Kobayashi Dr. Yuuya Kasahara Dr. Kunihiko Morihiro Prof. Dr. Taroh Satoh Prof. Dr. Yuichiro Doki Prof. Dr. Masaki Mori Prof. Dr. Hideshi Ishii Prof. Dr. Satoshi Obika 《ChemMedChem》2019,14(15):1384-1391
The main concern in the use of anticancer chemotherapeutic drugs is host toxicity. Patients need to interrupt or change chemotherapy due to adverse effects. In this study, we aimed to decrease adverse events with gemcitabine (GEM) in the treatment of pancreatic ductal adenocarcinoma and focused on the difference of hydrogen peroxide levels in normal versus cancer cells. We designed and synthesized a novel boronate-ester-caged prodrug that is activated by the high H2O2 concentrations found in cancer cells to release GEM. An H2O2-activatable GEM (A-GEM) has higher selectivity for H2O2 over other reactive oxygen species (ROS) and cytotoxic effects corresponding to the H2O2 concentration in vitro. A xenograft model of immunodeficient mice indicated that the effect of A-GEM was not inferior to that of GEM when administered in vivo. In particular, myelosuppression was significantly decreased following A-GEM treatment compared with that following GEM treatment. 相似文献
884.
885.
Erfina Oktariani Atsushi Noda Kazuya Nakashima Keisuke Tahara Bing Xue Koichi Nakaso Jun Fukai 《国际能源研究杂志》2012,36(11):1077-1087
An adsorption heat pump with a direct contact system for steam generation has been developed and the feasibility of the proposed system was confirmed both theoretically and experimentally. The basic cycle for the system has been proposed to use zeolite–water working pairs in the p‐T‐x equilibrium curve. To generate steam above 150°C from low‐energy level water at 80°C, a direct contact adsorption heat pump prototype was constructed. The experimental results show that steam could be generated by the direct contact system and the relationship between the amount of water adsorbed and the change in temperature with time is discussed. This study is expected to serve as a foundation for developing continuous adsorption heat pump systems for steam generation. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
886.
Synthesis,kinetic study,and reaction mechanism of Li4SiO4 with CO2 in a slurry bubble column reactor
AbstractThis study was performed to investigate the synthesis, kinetic and reaction mechanism of Li4SiO4 with CO2 in a slurry bubble column reactor. The Li4SiO4 powder sample was prepared via a solid-state reaction. The sample was characterized via X-ray diffraction (XRD) analysis and verified as a single phase. The median diameter of the sample was measured using the laser diffraction and scattering method as about 20?μm. The synthesized sample was suspended in binary molten carbonate of Li2CO3–K2CO3 having a molar ratio of 38:62. The experimental results show that Li4SiO4 in the slurry bubble column absorbed approximately a stoichiometric amount of CO2. The kinetic study shows that the CO2 reaction behavior on the Li4SiO4 surface was fitted to a double exponential model and the limiting step of the reaction was lithium diffusion. The mass transfer coefficient of CO2 and rate constant of reaction with Li4SiO4 were studied to understand the overall absorption mechanism in the reactor. The resistance for the direct reaction of CO2 on the Li4SiO4 was much smaller than the resistance for the mass transfer of CO2 to the Li4SiO4. We can conclude that the direct contact of CO2 with Li4SiO4 was the main path for the reaction. 相似文献
887.
This study focuses on the opening mode of induction bends; this mode represents the deformation outside a bend. Bending experiments on induction bends are shown and the manner of failure of these bends was investigated. Ruptures occur at the intrados of the bends, which undergo tensile stress, and accompany the local reduction in wall thickness, i.e. necking that indicates strain localization. By implementing finite element analysis (FEA), it was shown that the rupture is dominated not by the fracture criterion of material but by the initiation of strain localization that is a deformation characteristic of the material. These ruptures are due to the rapid increase in local strain after the initiation of strain localization and suddenly reach the fracture criterion. For the evaluation of the deformability of the bends, a method based on FEA that can predict the displacement at the rupture is proposed. We show that the yield surface shape and the true stress–strain relationship after uniform elongation have to be defined on the basis of the actual properties of the bend material. The von Mises yield criterion, which is commonly used in cases of elastic–plastic FEA, could not predict the rupture and overestimated the deformability. In contrast, a yield surface obtained by performing tensile tests on a biaxial specimen could predict the rupture. The prediction of the rupture was accomplished by an inverse calibration method that determined the true stress–strain relationship after uniform elongation. 相似文献
888.
889.
Hirofumi Ohashi Feng Wang Frank Stappenbeck Kana Tsuchimoto Chisa Kobayashi Wakana Saso Michiyo Kataoka Masako Yamasaki Kouji Kuramochi Masamichi Muramatsu Tadaki Suzuki Camille Sureau Makoto Takeda Takaji Wakita Farhad Parhami Koichi Watashi 《International journal of molecular sciences》2021,22(6)
The development of effective antiviral drugs targeting the severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) is urgently needed to combat the coronavirus disease 2019 (COVID-19). We have previously studied the use of semi-synthetic derivatives of oxysterols, oxidized derivatives of cholesterol as drug candidates for the inhibition of cancer, fibrosis, and bone regeneration. In this study, we screened a panel of naturally occurring and semi-synthetic oxysterols for anti-SARS-CoV-2 activity using a cell culture infection assay. We show that the natural oxysterols, 7-ketocholesterol, 22(R)-hydroxycholesterol, 24(S)-hydroxycholesterol, and 27-hydroxycholesterol, substantially inhibited SARS-CoV-2 propagation in cultured cells. Among semi-synthetic oxysterols, Oxy210 and Oxy232 displayed more robust anti-SARS-CoV-2 activities, reducing viral replication more than 90% at 10 μM and 99% at 15 μM, respectively. When orally administered in mice, peak plasma concentrations of Oxy210 fell into a therapeutically relevant range (19 μM), based on the dose-dependent curve for antiviral activity in our cell-based assay. Mechanistic studies suggest that Oxy210 reduced replication of SARS-CoV-2 by disrupting the formation of double-membrane vesicles (DMVs); intracellular membrane compartments associated with viral replication. Our study warrants further evaluation of Oxy210 and Oxy232 as a safe and reliable oral medication, which could help protect vulnerable populations with increased risk of developing COVID-19. 相似文献
890.
Koichi Ui Shinei KikuchiYasuhiro Jimba Naoaki Kumagai 《Journal of power sources》2011,196(8):3916-3920
In order to easily and simply improve the cyclability of the Sn film negative electrode, we selected Co as a matrix metal and tried to prepare the Co-Sn alloy film negative electrode by a pulse electrodeposition method. The surface morphology of the deposit was almost the same as that of the Sn film, although aggregation partially occurred. The content rate of Co and Sn in the deposit was almost the same as the composition percentage in the electrodeposition bath. X-ray diffraction measurement showed that the deposited film could be assigned to a metastable Co-Sn alloy, while the co-deposition of crystalline Sn was not observed. The galvanostatic charge-discharge tests indicated that the discharge capacity and the charge-discharge efficiency of the Co30.5Sn69.5 alloy film electrode at the 1st cycle were 529.2 mAh g−1 and 87.9%, respectively. Furthermore, the film electrode showed a good cyclability and discharge capacity of 470.5-617.5 mAh g−1 during 50 cyclings. Alloying Sn with inactive Co could effectively improve the cyclability of the Sn film electrode prepared by the pulse electrodeposition method. 相似文献