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71.
Dorofeeva T. I. Gubaidullina T. A. Gritsenko B. P. Sergeev V. P. 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(4):695-699
Protection of Metals and Physical Chemistry of Surfaces - In this work, preparation of thermal barrier coatings based on zirconium oxide is shown. The phased treatment of the copper substrate is... 相似文献
72.
R. Satheeskumar Bonam Raghavaiah S. Geerthik T. Senthil Kumar 《Concurrency and Computation》2024,36(1):e7873
This article proposes a high efficiency video coding (HEVC) standard hardware using block matching motion estimation algorithm. A hybrid parallel spiral and adaptive threshold star diamond search algorithm (Hyb PS-ATSDSA) proposes for fast motion estimation in HEVC. Parallel spiral search approach utilizes spiral pattern for searching from center to the surroundings and adaptive threshold SDA consists of two phases, they are adaptive threshold and star diamond algorithm. To lower computational complexities in HEVC architecture, parallel spiral search algorithm uses several blocks matching schemes. Adaptive threshold and star diamond algorithm are used to reduce the matching errors and remove the invalid blocks early from the procedure of motion estimation and finally predicts the final motion of the image. Speed is increased while using this hybrid algorithm. Proposed structure is carried out in Xilinx; ISE 14.5 design suit, then the experimental outcomes are analyzed to existing motion estimation strategies in field-programmable gate array devices. Experimental performance of the proposed Hyb-PS-ATSDSA-ME-HEVC method attains lower delay 33.97%, 32.97%, 62.97, and 26.97%, and lower area 34.867%, 45.97%, 27.97%, and 43.967% compared with the existing methods, such as FSA-ME-HEVC, TZSA-ME-HEVC, hyb TZSA-IME-HEVC, and IBMSA-ME-HEVC, respectively. 相似文献
73.
Sudhir Pandey Corina T. Madreiter-Sokolowski Supachoke Mangmool Warisara Parichatikanond 《International journal of molecular sciences》2022,23(22)
Patients with type two diabetes mellitus (T2DM) are at increased risk for cardiovascular diseases. Impairments of endothelin-1 (ET-1) signaling and mTOR pathway have been implicated in diabetic cardiomyopathies. However, the molecular interplay between the ET-1 and mTOR pathway under high glucose (HG) conditions in H9c2 cardiomyoblasts has not been investigated. We employed MTT assay, qPCR, western blotting, fluorescence assays, and confocal microscopy to assess the oxidative stress and mitochondrial damage under hyperglycemic conditions in H9c2 cells. Our results showed that HG-induced cellular stress leads to a significant decline in cell survival and an impairment in the activation of ETA-R/ETB-R and the mTOR main components, Raptor and Rictor. These changes induced by HG were accompanied by a reactive oxygen species (ROS) level increase and mitochondrial membrane potential (MMP) loss. In addition, the fragmentation of mitochondria and a decrease in mitochondrial size were observed. However, the inhibition of either ETA-R alone by ambrisentan or ETA-R/ETB-R by bosentan or the partial blockage of the mTOR function by silencing Raptor or Rictor counteracted those adverse effects on the cellular function. Altogether, our findings prove that ET-1 signaling under HG conditions leads to a significant mitochondrial dysfunction involving contributions from the mTOR pathway. 相似文献
74.
75.
Chao Xiang Yu-Fei Ao Matthias Hhne Uwe T. Bornscheuer 《International journal of molecular sciences》2022,23(23)
Amine transaminases (ATAs) are powerful biocatalysts for the stereoselective synthesis of chiral amines. However, wild-type ATAs usually show pH optima at slightly alkaline values and exhibit low catalytic activity under physiological conditions. For efficient asymmetric synthesis ATAs are commonly used in combination with lactate dehydrogenase (LDH, optimal pH: 7.5) and glucose dehydrogenase (GDH, optimal pH: 7.75) to shift the equilibrium towards the synthesis of the target chiral amine and hence their pH optima should fit to each other. Based on a protein structure alignment, variants of (R)-selective transaminases were rationally designed, produced in E. coli, purified and subjected to biochemical characterization. This resulted in the discovery of the variant E49Q of the ATA from Aspergillus fumigatus, for which the pH optimum was successfully shifted from pH 8.5 to 7.5 and this variant furthermore had a two times higher specific activity than the wild-type protein at pH 7.5. A possible mechanism for this shift of the optimal pH is proposed. Asymmetric synthesis of (R)-1-phenylethylamine from acetophenone in combination with LDH and GDH confirmed that the variant E49Q shows superior performance at pH 7.5 compared to the wild-type enzyme. 相似文献
76.
Wei Wuli Shinn-Zong Lin Shee-Ping Chen Bakhos A. Tannous Wen-Sheng Huang Peng Yeong Woon Yang-Chang Wu Hsueh-Hui Yang Yi-Cheng Chen Renata Lopes Fleming Jack T. Rogers Catherine M. Cahill Tsung-Jung Ho Tzyy-Wen Chiou Horng-Jyh Harn 《International journal of molecular sciences》2022,23(18)
Presenilin-1 (PSEN1) is a crucial subunit within the γ-secretase complex and regulates β-amyloid (Aβ) production. Accumulated evidence indicates that n-butylidenephthalide (BP) acts effectively to reduce Aβ levels in neuronal cells that are derived from trisomy 21 (Ts21) induced pluripotent stem cells (iPSCs). However, the mechanism underlying this effect remains unclear. This article aims to investigate the possible mechanisms through which BP ameliorates the development of Alzheimer’s disease (AD) and verify the effectiveness of BP through animal experiments. Results from RNA microarray analysis showed that BP treatment in Ts21 iPSC-derived neuronal cells reduced long noncoding RNA (lncRNA) CYP3A43-2 levels and increased microRNA (miR)-29b-2-5p levels. Bioinformatics tool prediction analysis, biotin-labeled miR-29b-2-5p pull-down assay, and dual-luciferase reporter assay confirmed a direct negative regulatory effect for miRNA29b-2-5p on lnc-RNA-CYP3A43-2 and PSEN1. Moreover, BP administration improved short-term memory and significantly reduced Aβ accumulation in the hippocampus and cortex of 3xTg-AD mice but failed in miR-29b-2-5p mutant mice generated by CRISP/Cas9 technology. In addition, analysis of brain samples from patients with AD showed a decrease in microRNA-29b-2-5p expression in the frontal cortex region. Our results provide evidence that the LncCYP3A43-2/miR29-2-5p/PSEN1 network might be involved in the molecular mechanisms underlying BP-induced Aβ reduction. 相似文献
77.
Joaquín Hernndez-Fernndez Ricardo Vivas-Reyes Carlos A. T. Toloza 《International journal of molecular sciences》2022,23(20)
During the production of polymer-grade propylene, different processes are used to purify this compound and ensure that it is of the highest quality. However, some impurities such as acetylene and methyl acetylene are difficult to remove, and some of these impurities may be present in the propylene used to obtain polypropylene, which may have repercussions on the process. This study evaluates the impact of these acetylene and methyl acetylene impurities on the productivity of the polypropylene synthesis process and on the mechanical and thermal properties of the material obtained through the synthesis of eight samples with different concentrations of acetylene and eight samples with different concentrations of acetylene. We discovered that for the first concentrations of both acetylene (2 and 3 ppm) and methyl acetylene (0.03 and 0.1), the MFI, thermal recording, and mechanical properties of the resin were unaffected by the variation of the fluidity index, thermal degradation by TGA, and mechanical properties such as resistance to tension, bending, and impact. However, when the concentration exceeded 14 ppm for methyl acetylene and 12 ppm for acetylene, the resistance of this resin began to decrease linearly. Regarding production, this was affected by the first traces of acetylene and methyl acetylene progressively decreasing. 相似文献
78.
Ayman Abo Elmaaty Wagdy M. Eldehna Muhammad Khattab Omnia Kutkat Radwan Alnajjar Ahmed N. El-Taweel Sara T. Al-Rashood Mohammed A. S. Abourehab Faizah A. Binjubair Mohamed A. Saleh Amany Belal Ahmed A. Al-Karmalawy 《International journal of molecular sciences》2022,23(20)
In this article, 34 anticoagulant drugs were screened in silico against the main protease (Mpro) of SARS-CoV-2 using molecular docking tools. Idraparinux, fondaparinux, eptifibatide, heparin, and ticagrelor demonstrated the highest binding affinities towards SARS-CoV-2 Mpro. A molecular dynamics study at 200 ns was also carried out for the most promising anticoagulants to provide insights into the dynamic and thermodynamic properties of promising compounds. Moreover, a quantum mechanical study was also conducted which helped us to attest to some of the molecular docking and dynamics findings. A biological evaluation (in vitro) of the most promising compounds was also performed by carrying out the MTT cytotoxicity assay and the crystal violet assay in order to assess inhibitory concentration 50 (IC50). It is worth noting that ticagrelor displayed the highest intrinsic potential for the inhibition of SARS-CoV-2 with an IC50 value of 5.60 µM and a safety index of 25.33. In addition, fondaparinux sodium and dabigatran showed promising inhibitory activities with IC50 values of 8.60 and 9.40 µM, respectively, and demonstrated safety indexes of 17.60 and 15.10, respectively. Moreover, the inhibitory potential of the SARS-CoV-2 Mpro enzyme was investigated by utilizing the SARS-CoV-2 Mpro assay and using tipranavir as a reference standard. Interestingly, promising SARS-CoV-2 Mpro inhibitory potential was attained for fondaparinux sodium with an IC50 value of 2.36 µM, surpassing the reference tipranavir (IC50 = 7.38 µM) by more than three-fold. Furthermore, highly eligible SARS-CoV-2 Mpro inhibitory potential was attained for dabigatran with an IC50 value of 10.59 µM. Finally, an SAR was discussed, counting on the findings of both in vitro and in silico approaches. 相似文献
79.
Rumana Yasmeen Quynhchi Pham Naomi K. Fukagawa Thomas T. Y. Wang 《International journal of molecular sciences》2022,23(20)
Adipose stem cells (ASCs) are reported to play a role in normal physiology as well as in inflammation and disease. The objective of this work was to elucidate inter-individual differences in growth, gene expression and response to inflammatory stimuli in ASCs from different donors. Human ASC1 (male donor) and ASC2 (female donor) were purchased from Lonza (Walkersville, MD). Cell proliferation was determined by the sulforhodamine B assay. After time-dependent treatment of ASCs with or without bacterial lipopolysaccharide (LPS), marker gene mRNAs for proliferation, steroid hormones, and xenobiotic and immune pathways were determined using RT-PCR, and secreted cytokine levels in media were measured using the Bio-Plex cytokine assay kit. ASCs from both donors expressed androgen receptors but not estrogen receptors. ASC2 had a 2-fold higher proliferation rate and a 6-fold higher level of proliferation marker Ki67 mRNA than ASC1. ASC2 exhibited significantly greater fold induction of TNF-α and CCL2 by LPS compared to ASC1. TNF-α and GM-CSF protein levels were also significantly higher in the LPS-induced ASC2 media, but IL-6 secretion was higher in the LPS-induced ASC1 media. Our findings suggest that inter-individual variability and/or possible sex differences exist in ASCs, which may serve as a key determinant to inflammatory responses of ASCs. 相似文献