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91.
Macrophages are major precursors of foam cells in atherosclerotic lesions. Acetylated low-density lipoproteins (acetyl LDL) taken up by macrophages through scavenger receptors are degraded by lysosomes and the released cholesterol is re-esterified, leading to foam cell formation. The ability of resident peritoneal macrophages from C57BL/6CrScl mice to form foam cells in relation to the donor age was assessed by the cholesterol esterification and the metabolism of acetyl LDL. The incorporation of 14C-oleate (complexed to albumin) into cellular cholesteryl esters in the presence of acetyl LDL (100 micrograms/ml) was significantly greater in macrophages from senescent mice (24-25 months) than in cells from young (3-4 months) mice (p < .001). The degradation and cellular association of acetyl LDL by macrophages from senescent mice were significantly greater than macrophages from mature mice, (p < .001 and p < .01, respectively), whereas the binding of acetyl LDL was similar in peritoneal macrophages from mature and senescent mice. These results suggest that the uptake and degradation of acetyl LDL, and the re-esterification by macrophages increase with advancing age and that the ability of macrophages to form foam cells increases with aging. The enhanced ability of senescent macrophages to form foam cells might contribute to the development and progression of atherosclerosis related to the aging process. 相似文献
92.
Two cases on non-Hodgkin's malignant lymphoma (NHL) of the testis are reported. A 63-year-old man with left painless scrotal swelling underwent orchiectomy. Although prophylactic irradiation was performed under the diagnosis of seminoma, subsequent immunohistochemistry revealed NHL, large diffuse cell type (B type). He had stage IEA disease. Chemotherapy with cyclophosphamide, adriamycin vincristine and prednisolone was performed. The second case was in a 63-year old man with right painless scrotal swelling. Orchiectomy revealed NHL, diffuse medium cell type (B type). Because of tumor in the retrosternum, he had stage IIIEA disease. Chemotherapy and irradiation to the contralateral testis was performed. 相似文献
93.
Coupled simulation of BES-CFD and performance assessment of energy recovery ventilation system for office model 总被引:1,自引:0,他引:1
Thermal comfort and indoor air quality as well as the energy efficiency have been recognized as essential parts of sustainable
building assessment. This work aims to analyze the energy conservation of the heat recovery ventilator and to investigate
the effect of the air supply arrangement. Three types of mixing ventilation are chosen for the analysis of coupling ANSYS/FLUENT
(a computational fluid dynamics (CFD) program) with TRNSYS (a building energy simulation (BES) software). The adoption of
mutual complementary boundary conditions for CFD and BES provides more accurate and complete information of indoor air distribution
and thermal performance in buildings. A typical office-space situated in a middle storey is chosen for the analysis. The office-space
is equipped with air-conditioners on the ceiling. A heat recovery ventilation system directly supplies fresh air to the office
space. Its thermal performance and indoor air distribution predicted by the coupled method are compared under three types
of ventilation system. When the supply and return openings for ventilation are arranged on the ceiling, there is no critical
difference between the predictions of the coupled method and BES on the energy consumption of HVAC because PID control is
adopted for the supply air temperature of the occupied zone. On the other hand, approximately 21% discrepancy for the heat
recovery estimation in the maximum between the simulated results of coupled method and BES-only can be obviously found in
the floor air supply ventilation case. The discrepancy emphasizes the necessity of coupling CFD with BES when vertical air
temperature gradient exists. Our future target is to estimate the optimum design of heat recovery ventilation system to control
CO2 concentration by adjusting flow rate of fresh air. 相似文献
94.
Hideaki Katayama Tsutomu Tawa Shinzaburo Ito Masahide Yamamoto Yoshio Wada 《Polymer Bulletin》1992,29(3-4):365-367
Summary The effect of side chain length on intramolecular triplet energy migration of naphthalene containing polymers was investigated by a delayed fluorescence (DF) spectroscopy for the solid solution of the polymers. The degree of triplet energy migration depends strongly on whether the chromophores are directly attached to the main chain or not. 相似文献
95.
The reaction mechanisms of a stage-1 fluorine-graphite intercalation compound (GIC), C2.5F, with 0.10 MPa of fluorine gas have been studied at 573-773 K. The original stage-1 structure of C2.5F with semi-ionic C-F bonds and planar sp2 carbon sheets is maintained in most part of the compound after the reaction at 573 K, although a large number of covalent C-F bonds are formed on the surface. This compound is partially or completely converted to poly(carbon monofluoride), (CF)n, with covalent C-F bonds and puckered sp3 carbon sheets at 673 or 773 K, respectively. Single-phase (CF)n obtained at 773 K possesses remarkably small BET specific surface area, 61 m2/g carbon, almost unchanged from the value of the precursor C2.5F (69 m2/g carbon). In this reaction, the accommodation of fluorine atoms supplied from the atmosphere into the galleries of C2.5F is facilitated by the rearrangement of originally intercalated fluorine atoms in the GIC, forming (CF)n with fewer defects compared to those by the conventional direct fluorination of graphite. 相似文献
96.
Dr. Kenichiro Ito Dr. Yoshihiko Matsuda Ayako Mine Kyohei Miyairi Dr. Yoshimi Kikuchi Dr. Atsushi Konishi 《Chembiochem : a European journal of chemical biology》2023,24(2):e202200599
The inhibition of protein-protein interactions (PPIs) is an effective approach for therapy. Owing to their large binding surface areas to target proteins, macrocyclic peptides are suitable molecules for PPI inhibition. In this study, we developed single-chain tandem macrocyclic peptides (STaMPtides) that inhibits the vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2). They were artificially designed to comprise two different VEGFR2-binding macrocyclic peptides linked in tandem by peptide linkers and secreted by Corynebacterium glutamicum. Most potent VEGFR2-inhibitory STaMPtides with length-optimized linkers exhibited >1000 times stronger inhibitory activity than their parental monomeric peptides, possibly due to the avidity effect of heterodimerization. Our approach of using STaMPtides for PPI inhibition may be used to inhibit other extracellular factors, such as growth factors and cytokines. 相似文献
97.
Hidenobu Mizuki Yudai Ito Saba Samatya Hisashi Harada Hidetaka Kawakita 《溶剂提取与离子交换》2013,31(1):146-156
Abstract A novel adsorbent Zr(IV)-immobilized resin was prepared to remove fluoride ions from tap water and industrial wastewater. In order to enhance both the kinetics and efficiency, large pathways were formed in the resin for fluoride ion adsorption and the Zr(IV)-phosphate complexes were immobilized on the polymer surface by surface-template polymerization. The Zr(IV)-immobilized resin had a fluoride adsorption capacity of 0.30 mmol/g. The morphology of the Zr(IV)-immobilized resin was evaluated by measuring the specific surface area, pore volume, and pore size distribution. The resin possessed large amounts of large macropores with diameters around 300 nm. The molecular structure at the fluoride adsorption sites was investigated by measuring the amounts of phosphorus, zirconium, and fluoride ion in the resin, and developing a model complex using computational chemistry. On the polymer surface, a fluoride ion/Zr(IV)/dioleyl phosphoric acid complex with an ideal F:Zr:P mole ratio of 3:1:3 could be formed. 相似文献
98.
Akihiko Ito Yu You Hirokazu Katsui Takashi Goto 《Journal of the European Ceramic Society》2013,33(13-14):2655-2661
Ba β-alumina films were prepared by laser chemical vapor deposition. Mostly single-phase Ba β-alumina films were obtained at 1125–1200 K and for an Al/Ba molar ratio of 12.4–16.6. BaAl2O4 and α-Al2O3 were codeposited with Ba β-alumina under Ba- and Al-rich conditions, respectively. The Ba β-alumina films consisted of hexagonal grains, and the (1 1 0)-oriented Ba β-alumina films had a fin-like columnar structure. The highest deposition rate reached 120 μm h?1 at around 1200 K. A thin layer of Ba-rich superstructure was formed on the surface of the (1 1 0)-oriented columnar grains. 相似文献
99.
Hidenori Okuzaki Kosuke Hosaka Hiroki Suzuki Takamichi Ito 《Reactive and Functional Polymers》2013,73(7):986-992
Free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) with various PSS contents were newly prepared by casting water dispersion of the PEDOT/PSS colloidal particles in the presence of an extra PSS. Electrical conductivity, morphology, water vapor sorption, and electro-active polymer actuating behavior of the resulting films were investigated by means of four-point method, atomic force microscope (AFM), sorption isotherm, and electromechanical analyses. The maximum contraction of the film by application of an electric field increased with increasing both PSS content and relative humidity (RH), where the value attained 7% at 70% RH for the film with 93% of PSS. Since the isothermal sorption curve of the film was less dependent on the PSS content, the significant increase of the film contraction was explained by two mechanisms: (i) the extra PSS prevented from hydrogen bonding between adjacent PEDOT/PSS particles that suppressed dimensional changes of the film; and (ii) the higher the RH, the larger the degree of water vapor sorption, which led to the large film contraction by desorption of water vapor via Joule heating. On the basis of this phenomenon linear actuators utilizing PEDOT/PSS films were successfully developed and applied to leverage actuator and Braille cell. 相似文献
100.
Transparent lutetium niobate (Lu3NbO7) bodies were prepared by reactive spark plasma sintering using Lu2O3 and Nb2O5 powders. Fully dense Lu3NbO7 bodies with density greater than 99.5% of the theoretical were obtained at 1300–1650 °C. The grains steadily grew from 0.1 to 0.6 μm with increasing sintering temperature from 1200 to 1450 °C and significant grain growth from 2.2 to 9.2 μm occurred at 1550–1650 °C. The Lu3NbO7 body sintered at 1450 °C showed the highest transmittance of 63% at 550 nm after heat treatment at 850 °C in air for 6 h. Fully dense, submicron-size transparent Lu3NbO7 exhibited Vickers hardness of ~13.0 GPa and indentation fracture toughness of 1.0 MPa m1/2. 相似文献