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It has been previously reported that Bryostatin 1 (Bryo1) induces differentiation of the human acute lymphoblastic leukemia (ALL) cell line, Reh, to a monocytoid B-cell stage. In this study we demonstrate that a novel protein, ubiquitin COOH-terminal hydrolase (UCH-L1), is associated with this differentiation. Reh cells were treated with 200 nmol/l of Bryo1 for 72 h and analyzed for changes in morphology, surface immunophenotype, acid phosphatase and terminal deoxynucleotidyl transferase. Protein patterns of the parent and differentiated cells, by two-dimensional polyacrylamide gel electrophoresis (2D PAGE), were studied. Bryo1-treated cells expressed morphologic, phenotypic and enzymatic features of the monocytoid B-cell stage. The UCH-L1 enzyme (MW-pl 34-5.3) was detected by 2 D PAGE in the differentiated, but not in parent cells. The presence of UCH-L1 in the Bryo1-treated cells was further confirmed by immunoblotting of 2 D PAGE using UCH-L1 polyclonal antibody. Ubiquitin expression was studied in parent and Bryo1-treated cells and was compared with 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated cells. Both agents, TPA and Bryo1, increased the level of ubiquitin expression as detected by flow cytometry. Sodium borohydride, an inhibitor of UCH-L1, inhibited the Bryo1-induced differentiating effect on Reh cells. To date, the mechanism by which Bryo1, exerts its B-cell differentiating effect is not fully understood. This study shows that UCH-L1 expression may play a major role in Bryo1-induced differentiation in pre-B-ALL. 相似文献
3.
In membrane filtration, solution environment factors such as pH and solvent density are important in controlling the filtration
rate and the rejection of the particles and/or the macromolecules. The filtration rate and the rejection in membrane filtration
have been investigated from physicochemical aspects. It was shown that the properties of the filter cake formed on the membrane
surface play a vital role in determining the filtration rate in mem-brane filtration. It was clearly demonstrated that such
filtration behaviors as the filtration rate and the rejection are highly dependent on the electrical nature of the particles
and/or the macromolecules. Furthermore, it was shown that the solvent density ρ has a large effect on the steady filtration
rate in upward ultrafiltration. 相似文献
4.
The redistribution of impurity in alite during recrystallization has been confirmed by means of the electron probe microanalysis. Each of the main impurity components shows a significant decrease in content during recrystallization. This demonstrates that the growth velocity of alite exerts influence on the amount of the impurity taken up in alite in solid solution from the interstitial melt. Whether M3 or M1 occurs at ambient temperature depends on the cooling rate of clinker as well as the chemical composition of alite. 相似文献
5.
Hideto Matsuyama Kentarou Hayashi Taisuke Maki Masaaki Teramoto Noboru Kubota 《应用聚合物科学杂志》2004,93(1):471-474
Microporous high‐density polyethylene (HDPE) and low‐density polyethylene (LDPE) hollow fiber membranes were prepared from polyethylene–diisodecyl phthalate solution via thermally induced phase separation. Effect of the polyethylene density on the membrane structure and performance was investigated. The HDPE membrane showed about five times higher water permeability than the LDPE membrane because it had the larger pore and the higher porosity at the outer membrane surface. The formation of the larger pore was owing to both the initial larger structure formed by spinodal decomposition and the suppression of the diluent evaporation from the outer membrane surface due to the higher solution viscosity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 471–474, 2004 相似文献
6.
Phase separation rate during porous membrane formation by immersion precipitation was investigated by light scattering in a polyimide/N‐Methylpyrrolidone (NMP)/water system. In the light scattering measurement, plots of scattered intensity against scattered angle showed maxima in all cases, which indicated that phase separation occurred by a spinodal decomposition (SD). Characteristic properties of the early stage of SD, such as an apparent diffusion coefficient Dapp and an interphase periodic distance Λ, were obtained. The growth process of Λ was also followed by light scattering. The growth rate had the same tendency as Dapp when water content in the nonsolvent bath and the polymer concentration in the cast solution were changed. The pore size of the final membrane increased with decreasing water content, which was opposite to the tendency of Λ growth rate. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 292–296, 2003 相似文献
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Fusaomi Nagata Takanori Mizobuchi Shintaro Tani Tetsuo Hase Zenku Haga Keigo Watanabe Maki K. Habib 《Artificial Life and Robotics》2010,15(1):106-110
In this article, a new desktop orthogonal-type robot, which has the capacity of stick-slip motion control based on cutter
location data, is presented for lapping small metallic molds with a curved surface. The robot consists of three single-axis
devices with a high position resolution of 1 μm. A thin wooden stick tool with a ball-end shape is attached to the tip of
the z-axis. In order to improve the lapping performance, a novel stick-slip motion control method is developed in the control system.
The small stick-slip motion is orthogonally generated in the direction of the tool’s movement. The effectiveness of stick-slip
motion control is examined through an actual lapping test of an LED lens cavity. 相似文献
9.
Zeming Lu Fusaomi Nagata Keigo Watanabe Maki K. Habib 《Artificial Life and Robotics》2017,22(3):374-379
With the progress of electronics technology, the development of civilian UAV (unmanned aerial vehicle) applications becomes possible. In addition, smartphones have rapidly gained popularity and become very important due to the simple operability and mobility. Hence, there is a need to have an easy and flexible way to control a UAV using such technology. In this study, a remote controller using an iOS device is developed for a quadrotor to enable remote control with easy operations. Four basic programs for obtaining compass information, controlling a gimbal, autopilot function for return, and video preview function are developed and implemented for an iOS device. The basic functionalities of the programs are evaluated and confirmed through experiments using a quadrotor and an iOS device. 相似文献
10.
Eight subjects participated in a subjective experiment of eight conditions to investigate the effects of heated seats in vehicles on skin temperature, thermal sensation and thermal comfort during the initial warm-up period. The experimental conditions were designed as a combination of air temperature in the test room (5, 10, 15, or 20 °C) and heated seat (on/off). The heated seat was effective for improving thermal comfort during the initial warm-up period when air temperature was lower than 15 °C. Use of heated seats prevented decreases in or increased toe skin temperature. Heated seats also increased foot thermal sensation at 15 and 20 °C. Optimal thermal sensation in contact with the seat was higher when air temperature was lower. Optimal skin temperature in contact with the seat back was higher than that with the seat cushion. Moreover, these optimal skin temperatures were higher when air temperature was lower. 相似文献