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71.
72.
Arun Pandian Chandrasekaran Sang Hyeon Woo Neha Sarodaya Byung Ho Rhie Apoorvi Tyagi Soumyadip Das Bharathi Suresh Na Re Ko Seung Jun Oh Kye-Seong Kim Suresh Ramakrishna 《International journal of molecular sciences》2021,22(11)
Cell division cycle 25A (Cdc25A) is a dual-specificity phosphatase that is overexpressed in several cancer cells and promotes tumorigenesis. In normal cells, Cdc25A expression is regulated tightly, but the changes in expression patterns in cancer cells that lead to tumorigenesis are unknown. In this study, we showed that ubiquitin-specific protease 29 (USP29) stabilized Cdc25A protein expression in cancer cell lines by protecting it from ubiquitin-mediated proteasomal degradation. The presence of USP29 effectively blocked polyubiquitination of Cdc25A and extended its half-life. CRISPR-Cas9-mediated knockdown of USP29 in HeLa cells resulted in cell cycle arrest at the G0/G1 phase. We also showed that USP29 knockdown hampered Cdc25A-mediated cell proliferation, migration, and invasion of cancer cells in vitro. Moreover, NSG nude mice transplanted with USP29-depleted cells significantly reduced the size of the tumors, whereas the reconstitution of Cdc25A in USP29-depleted cells significantly increased the tumor size. Altogether, our results implied that USP29 promoted cell cycle progression and oncogenic transformation by regulating protein turnover of Cdc25A. 相似文献
73.
Sang-Hyun Park Insu Shin Dr. Gun-Hee Kim Dr. Sung-Kyun Ko Prof. Dr. Injae Shin 《Chembiochem : a European journal of chemical biology》2021,22(24):3425-3430
A novel autophagy inhibitor, autophazole (Atz), which promoted cancer cell death via caspase activation, is described. This compound was identified from cell-based high-content screening of an imidazole library. The results showed that Atz was internalized into lysosomes of cells where it induced lysosomal membrane permeabilization (LMP). This process generated nonfunctional autolysosomes, thereby inhibiting autophagy. In addition, Atz was found to promote LMP-mediated apoptosis. Specifically, LMP induced by Atz caused release of cathepsins from lysosomes into the cytosol. Cathepsins in the cytosol cleaved Bid to generate tBid, which subsequently activated Bax to induce mitochondrial outer membrane permeabilization (MOMP). This event led to cancer cell death via caspase activation. Overall, the findings suggest that Atz will serve as a new chemical probe in efforts aimed at gaining a better understanding of the autophagic process. 相似文献
74.
The effects of annealing and annealing with a superimposed pressure of 940 MPa on the primary crystallization behaviour of α-Al and the resulting micro-hardness have been studied for as-quenched Al87Ni7Gd6 metallic glass. Isothermal annealing experiments were conducted for 30 min at 188 °C, 191 °C, and 205 °C in silicone oil maintained either at atmospheric pressure (i.e. 0.1 MPa) or at 940 MPa. XRD analyses detected the evolution of structure with annealing at 0.1 MPa, while specimens annealed with 940 MPa pressure exhibited sharper diffraction peaks than those annealed at 0.1 MPa. DSC measurements were conducted on the as-received amorphous ribbons as well as ribbons annealed at different temperatures at either 0.1. MPa or with 940 MPa superimposed pressure. Specimens annealed with 940 MPa pressure exhibited higher onset temperatures (i.e. Tx1) and temperatures for the first exothermic peak (i.e. Tp1) for primary crystallization. TEM measurements revealed an increase in the volume fraction of α-Al with increases in annealing temperature, while micro-hardness measurements revealed an increase in hardness with increasing amounts of α-Al. Specimens annealed with 940 MPa pressure exhibited further increases in both the volume fraction of α-Al and resulting micro-hardness. 相似文献
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77.
In this work mathematical models were developed to represent the kinetics of volume changes of fluid spaces associated with
infusion of Ringer’s solution. During infusion of Ringer’s solution, the human body is assumed to be characterized by the
two-fluid space model which has second volume space in addition to the first volume so that fluid exchanges between these
two spaces are possible. Various infusion types were tested to accommodate different medical situations. Volunteers were given
Ringer’s solution and the changes in blood hemoglobin were detected. From the comparison with experimental data, the two-fluid
space model was found to represent adequately the kinetics of human volume expansion during infusion of Ringer’s solution. 相似文献
78.
Byung-Han Ko Sang-Geuk Jeong Young-Ghyu Ahn Kyoung-Su Park No-Cheol Park Young-Pil Park 《Microsystem Technologies》2014,20(8-9):1671-1677
Acoustic noise generated by a multi-layer ceramic capacitor (MLCC) makes users uncomfortable, so the problem must be analyzed to reduce the noise. There is a correlation between the acoustic noise and the vibration of MLCCs and the circuit board. Therefore, the acoustic noise problem must be investigated from a vibration perspective. In this study, the acoustic noise-generating mechanism was investigated, and the relationship between the characteristics of the noise and the dynamic characteristics of the circuit board with MLCC was analyzed. And a correlation criterion was proposed to predict the acoustic noise using the vibration response of the circuit board. 相似文献
79.
Requirements engineering (RE) offers the means to discover, model, and manage the requirements of the products that comprise a product line, while software product line engineering (SPLE) offers the means of realizing the products’ requirements from a common base of software assets. In practice, however, RE and SPLE have proven to be less complementary than they should. While some RE techniques, particularly goal modeling, support the exploration of alternative solutions, the appropriate solution is typically conditional on context and a large product line may have many product-defining contexts. Thus, scalability and traceability through into product line features are key challenges for RE. Feature modeling, by contrast, has been widely accepted as a way of modeling commonality and variability of products of a product line that may be very complex. In this paper, we propose a goal-driven feature modeling approach that separates a feature space in terms of problem space and solution space features, and establish explicit mappings between them. This approach contributes to reducing the inherent complexity of a mixed-view feature model, deriving key engineering drivers for developing core assets of a product line, and facilitating the quality-based product configuration. 相似文献
80.
Tae Hwan Kim B. Ramachandra Jung Sik Choi M. B. Saidutta Ko Yeon Choo Sun-Dal Song Young-Woo Rhee 《Catalysis Letters》2004,98(2-3):161-165
Methanol selective oxidation to formaldehyde over a modified Fe-Mo catalyst with two different stoichiometric (Mo/Fe atomic ratio = 1.5 and 3.0) was studied experimentally in a fixed bed reactor over a wide range of reaction conditions. The physicochemical characterization of the prepared catalysts provides evidence that Fe2(MoO4)3 is in fact the active phase of the catalyst. The experimental results of conversion of methanol and selectivity towards formaldehyde for various residence times were studied. The results showed that as the residence time increases the yield of formaldehyde decreases. Selectivity of formaldehyde decreases with increase in residence time. This result is attributable to subsequent oxidation of formaldehyde to carbon monoxide due to longer residence time. 相似文献