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51.
Guglielmina Chimienti Anna Picca Flavio Fracasso Francesco Russo Antonella Orlando Giuseppe Riezzo Christiaan Leeuwenburgh Vito Pesce Angela Maria Serena Lezza 《International journal of molecular sciences》2021,22(4)
Calorie restriction (CR) is the most efficacious treatment to delay the onset of age-related changes such as mitochondrial dysfunction. However, the sensitivity of mitochondrial markers to CR and the age-related boundaries of CR efficacy are not fully elucidated. We used liver samples from ad libitum-fed (AL) rats divided in: 18-month-old (AL-18), 28-month-old (AL-28), and 32-month-old (AL-32) groups, and from CR-treated (CR) 28-month-old (CR-28) and 32-month-old (CR-32) counterparts to assay the effect of CR on several mitochondrial markers. The age-related decreases in citrate synthase activity, in TFAM, MFN2, and DRP1 protein amounts and in the mtDNA content in the AL-28 group were prevented in CR-28 counterparts. Accordingly, CR reduced oxidative mtDNA damage assessed through the incidence of oxidized purines at specific mtDNA regions in CR-28 animals. These findings support the anti-aging effect of CR up to 28 months. Conversely, the protein amounts of LonP1, Cyt c, OGG1, and APE1 and the 4.8 Kb mtDNA deletion content were not affected in CR-28 rats. The absence of significant differences between the AL-32 values and the CR-32 counterparts suggests an age-related boundary of CR efficacy at this age. However, this only partially curtails the CR benefits in counteracting the generalized aging decline and the related mitochondrial involvement. 相似文献
52.
持久蠕变强度外推是预测材料在高温高压环境下工作寿命的有效方法。目前常用的外推方法有等温法和参数法。这两种方法都是通过在实验室中采用较短时间的试验,获取试验数据后,通过Excel或者MATLAB等数据处理软件进行数据的拟合处理和外推计算。这些数据归纳统计和数学建模的过程有时需要耗费试验人员的大量精力。介绍了持久蠕变强度外推的软件实现方法,该功能包含在持久蠕变试验设备配备的软件中,试验完成后,软件直接根据试验结果进行数据拟合和持久蠕变强度的外推计算,无需试验数据的统计和建模,大大提高了持久蠕变强度外推计算的效率。 相似文献
53.
Daisuke Yamanaka Suzuka Kurita Yuka Hanayama Yoshiyuki Adachi 《International journal of molecular sciences》2021,22(4)
β-Glucan is widely distributed in various plants and microorganisms and is composed of β-1,3-linked d-glucose units. It may have a branched short or long side chain of glucose units with β-1,6- or β-1,4-linkage. Numerous studies have investigated different β-glucans and revealed their bioactivities. To understand the structure-function relationship of β-glucan, we constructed a split-luciferase complementation assay for the structural analysis of long-chain β-1,6-branched β-1,3-glucan. The N- and C-terminal fragments of luciferase from deep-sea shrimp were fused to insect-derived β-1,3-glucan recognition protein and fungal endo-β-1,6-glucanase (Neg1)-derived β-1,6-glucan recognition protein, respectively. In this approach, two β-glucan recognition proteins bound to β-glucan molecules come into close proximity, resulting in the assembly of the full-length reporter enzyme and induction of transient luciferase activity, indicative of the structure of β-glucan. To test the applicability of this assay, β-glucan and two β-glucan recognition proteins were mixed, resulting in an increase in the luminescence intensity in a β-1,3-glucan with a long polymer of β-1,6-glucan in a dose-dependent manner. This simple test also allows the monitoring of real-time changes in the side chain structure and serves as a convenient method to distinguish between β-1,3-glucan and long-chain β-1,6-branched β-1,3-glucan in various soluble and insoluble β-glucans. 相似文献
54.
周家荣 《电信工程技术与标准化》2021,34(9)
移动边缘云是公司“云+5G”双引擎战略的最佳契合点,边缘网络是发挥移动云“大云”产品和5G网络融合优势,实现云网统筹、构建运营商“连接+计算”核心能力的关键。运营商传统接入网存在云网割裂、分段入云和组网复杂等突出问题,难以适应边缘业务敏捷交付要求。本文通过深入分析边缘云业务特征和技术架构,对标业界主流云商建设实践,研究基于云网PoP网的边缘网络建设思路,创新性提出云网一体化规划设计和建设交付流程变革,基于云网POP统一网络和业务锚点,构建Overlay和Underlay融合双层加速网络架构,探索Spine-leaf化的新型城域接入网实现L3下沉和弹性扩容等方法,实现“云+网+应用”一体化敏捷交付的边缘网络能力。 相似文献
55.
本文提出一种基于实时几何测距的船桥主动防撞方法。该方法对船的改动量甚微,仅需维持多项距离矩阵,通过告警逻辑矩阵进行展示与告警,能起到很好的船桥防撞提示效果。 相似文献
56.
《Ceramics International》2021,47(22):31073-31083
Pluronic 31R1 surfactant and MCM-41 silica were used to fabricate mesoporous Ag2O/g-C3N4 heterostructures with improved surface areas. The fabricated mesoporous nanocomposite was used to photo oxidize ciprofloxacin. The TEM images of Ag2O/g-C3N4 indicated a uniform dispersion of spherical approximately 4-nm Ag2O nanoparticles on g-C3N4. The mesoporous 0.9% Ag2O@g-C3N4 heterostructure exhibited 100% efficiency in ciprofloxacin oxidation within 60 min when compared with the 25% efficiency in 120 min of pure mesoporous Ag2O and 10% efficiency in 120 min of pure g-C3N4. The highest ciprofloxacin oxidation efficiency achieved was 100%, which was four and ten times better than those of Ag2O and g-C3N4, respectively. This superior performance of the mesoporous Ag2O/g-C3N4 was attributed to the high dispersion of nano-sized mesoporous Ag2O particles on the g-C3N4 surface, narrow bandgap, and significantly high surface areas. The powerful interaction between Ag2O and g-C3N4 ensured robust durability of Ag2O/g-C3N4 heterostructures, which is evident in the fact that five recycling trials of the photocatalyst rendered a minimal loss of efficiency. 相似文献
57.
Saerom Lee Ga-Eun Lim Yong-Nyun Kim Hyeon-Sook Koo Jaegal Shim 《International journal of molecular sciences》2021,22(4)
The extracellular matrix (ECM) is important for normal development and disease states, including inflammation and fibrosis. To understand the complex regulation of ECM, we performed a suppressor screening using Caenorhabditis elegans expressing the mutant ROL-6 collagen protein. One cuticle mutant has a mutation in dpy-23 that encodes the μ2 adaptin (AP2M1) of clathrin-associated protein complex II (AP-2). The subsequent suppressor screening for dpy-23 revealed the lon-2 mutation. LON-2 functions to regulate body size through negative regulation of the tumor growth factor-beta (TGF-β) signaling pathway responsible for ECM production. RNA-seq analysis showed a dominant change in the expression of collagen genes and cuticle components. We noted an increase in the cav-1 gene encoding caveolin-1, which functions in clathrin-independent endocytosis. By knockdown of cav-1, the reduced TGF-β signal was significantly restored in the dpy-23 mutant. In conclusion, the dpy-23 mutation upregulated cav-1 expression in the hypodermis, and increased CAV-1 resulted in a decrease of TβRI. Finally, the reduction of collagen expression including rol-6 by the reduced TGF-β signal influenced the cuticle formation of the dpy-23 mutant. These findings could help us to understand the complex process of ECM regulation in organism development and disease conditions. 相似文献
58.
59.
60.
Constantin Tnase Lucia Pintilie Raluca Elena Tnase 《International journal of molecular sciences》2021,22(4)
In the total stereo-controlled synthesis of natural prostaglandins (PGs) and their structural analogs, a vast class of compounds and drugs, known as the lactones, are encountered in a few key steps to build the final molecule, as: δ-lactones, γ-lactones, and 1,9-, 1,11-, and 1,15-macrolactones. After the synthesis of 1,9-PGF2α and 1,15-PGF2α lactones, many 1,15-lactones of E2, E3, F2, F3, A2, and A3 were found in the marine mollusc Tethys fimbria and the quest for understanding their biological role stimulated the research on their synthesis. Then 1,9-, 1,11-, and 1,15-PG lactones of the drugs were synthesized as an alternative to the corresponding esters, and the first part of the paper describes the methods used for their synthesis. The efficient Corey procedure for the synthesis of prostaglandins uses the key δ-lactone and γ-lactone intermediates with three or four stereocenters on the cyclopentane fragment to link the PG side chains. The paper describes the most used procedures for the synthesis of the milestone δ-Corey-lactones and γ-Corey-lactones, their improvements, and some new promising methods, such as interesting, new stereo-controlled and catalyzed enantioselective reactions, and methods based on the chemical/enzymatic resolution of the compounds in different steps of the sequences. The many uses of δ-lactones not only for the synthesis of γ-lactones, but also for obtaining 9β-halogen-PGs and halogen-substituted cyclopentane intermediates, as synthons for new 9β-PG analogs and future applications, are also discussed. 相似文献