Star polymers containing ruthenium complex in the core were prepared by ruthenium-catalyzed living radical polymerization, where the metal catalysts were directly encapsulated on linking reactions of ...living poly(MMA) in the presence of ethylene glycol dimethacrylate as a linker and diphenyl-4-styrylphosphine as a ligand incorporated in the core. The products were characterized by SEC/MALLS, UV−vis, NMR, AFM, TEM, and ICP-AES and were employed as polymer catalysts for the oxidation reaction of alcohol.
Single fluorophores in aqueous solution were imaged in real time with a conventional silicon‐intensified target video camera connected to an unmodified commercial microscope (IX70, Olympus) with ...epifluorescence excitation with a high‐pressure mercury lamp. Neither a powerful laser nor an extremely sensitive video camera was required. Three experimental systems were used to demonstrate quantitatively that individual, moving or stationary Cy3 fluorophores could be imaged with the microscope: Cy3‐gelsolin attached to an actin filament sliding over heavy meromyosin, sliding actin filaments sparsely labelled with Cy3, and heavy meromyosin labelled with one or two Cy3 fluorophores. The results should encourage many laboratories to attempt ‘single‐molecule physiology’ in which the functions and mechanisms of molecular machines are studied at the single‐molecule level in an environment where the biological machines are fully active.
A surface of a diamond thin film grown homoepitaxially on a C(001) substrate by microwave plasma chemical vapor deposition (CVD) has been studied using reflection high-energy electron diffraction ...(RHEED) and atomic force microscopy (AFM). The RHEED pattern showed the C(001)2×1/1×2 double-domain structure. The AFM images taken from the same sample in air showed 1×1 but locally 2×1 structure, which was confirmed by the Fourier transformed pattern of the AFM image.
To investigate the role of telomerase activity in colorectal adenoma-carcinomas, telomerase activity, human telomerase RNA component (hTERC) and human telomerase reverse transcriptase (hTERT) mRNA ...were quantitatively analyzed in human cancerous and precancerous colorectal tissues. Sixty-six colorectal tumor specimens, including 10 invasive carcinomas, 6 mucosal carcinomas and 50 adenomas were evaluated. Ten specimens of normal tissue were also included in the study. Telomerase activity was assayed by semiquantitative fluorescence using the TRAP-eze(TM) telomerase detection kit. Analysis of the expression of each telomerase subunit gene was performed by real-time PCR amplification. There was a positive correlation between histological atypia and telomerase activity (rho = 0.700, p < 0.0001), hTERT mRNA expression (rho = 0.603, p < 0.0001), and hTERC expression (rho = 0.290, p < 0.05). There was also a positive correlation between the levels of hTERT mRNA and telomerase activity (r = 0.455, p < 0.01). Significant differences in the levels of hTERT mRNA were shown between normal tissues and the adenomas (p < 0.05) and between the mucosal carcinomas and invasive carcinomas (p < 0.05). The values of hTERC expression in neoplastic tissues were significantly higher than in the normal tissues; however, there were no significant differences between the adenomas and the carcinomas. In summary, although upregulation of hTERC expression is an early event in adenoma development, hTERT mRNA expression is gradually upregulated during the adenoma-carcinoma sequence and may be a rate-limiting determinant of telomerase activity.
can cause decrease of the fatigue strength of carburized steel components. This artefact is considered to derive from a change in crack-initiation behaviour at the surface. However, grain coarsening ...can increase the hardenability of steel and thereby avoid the addition of alloying elements bringing about such hardenability. Thus, it is expected that steel with a dual-layer structure of a fine grain layer at the surface and a coarse grain layer in the inside achieves good fatigue strength and high hardenability while saving alloy elements. In this study, low pressure carburizing of JIS SCR420-Low N steels were carried out at 1323 K, both with and without the use of NH
gas as a source of N to precipitate AlN. After carburizing without NH
gas, only coarse grains were observed from the surface to the inside of the specimens. In contrast, after carburizing with NH
gas, a dual layer structure with only fine grains at the surface and only coarse grains at the inside was observed. These results show that a dual-layer structure can be successfully obtained through the control of the AlN precipitation behavior by optimizing NH
gas conditions during low pressure carburizing.
JT-60U has a variety of wall-conditioning methods such as baking of the vacuum vessel, helium Taylor discharge cleaning, helium glow discharge cleaning, tokamak discharge cleaning, and boronization. ...Using these wall-conditioning methods, the high-power operation of JT-60U has been successfully carried out with the carbon-based first wall. The material behavior of the carbon-based first wall has been investigated, and important knowledge was obtained on mechanical engineering and plasma surface interactions. In order to understand the tritium behavior in JT-60U, tritium retention in the first wall and tritium exhausted through the pumping system were measured. These results yield useful information on the tritium behavior in a future DT fusion machine.
In this work we report a novel method to efficiently induce a murine model of Graves' hyperthyroidism. Inbred mice of different strains were immunized by i.m. injection with adenovirus expressing ...thyrotropin receptor (TSHR) or beta-galactosidase (1 x 10(11) particles/mouse, three times at 3-wk intervals) and followed up to 8 wk after the third immunization. Fifty-five percent of female and 33% of male BALB/c (H-2(d)) and 25% of female C57BL/6 (H-2(b)) mice developed Graves'-like hyperthyroidism with elevated serum thyroxine (T(4)) levels and positive anti-TSHR autoantibodies with thyroid-stimulating Ig (TSI) and TSH-binding inhibiting Ig (TBII) activities. In contrast, none of female CBA/J (H-2(k)), DBA/1J (H-2(q)), or SJL/J (H-2(s)) mice developed Graves' hyperthyroidism or anti-TSHR autoantibodies except SJL/J, which showed strong TBII activities. There was a significant positive correlation between TSI values and T(4) levels, but the correlations between T(4) and TBII and between TSI and TBII were very weak. TSI activities in sera from hyperthyroid mice measured with some chimeric TSH/lutropin receptors suggested that their epitope(s) on TSHR appeared similar to those in patients with Graves' disease. The thyroid glands from hyperthyroid mice displayed diffuse enlargement with hypertrophy and hypercellularity of follicular epithelia with occasional protrusion into the follicular lumen, characteristics of Graves' hyperthyroidism. Decreased amounts of colloid were also observed. However, there was no inflammatory cell infiltration. Furthermore, extraocular muscles from hyperthyroid mice were normal. Thus, the highly efficient means that we now report to induce Graves' hyperthyroidism in mice will be very useful for studying the pathogenesis of autoimmunity in Graves' disease.
Washed Escherichia coli ATCC11775 cells were killed by (–)‐epigallocatechin (EGC) in the presence of a non‐ lethal concentration of Cu2+ (1 μmol l−1) without additional H2O2, but not by ...(–)‐epicatechin (EC). EGC alone (< 0·1 mmol l−1) did not reduce the viability of the cells. The survival curve obtained in the presence of EGC and Cu2+ was similar to that obtained in the presence of (–)‐adrenaline (EN) and Cu2+.
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