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31.
In recent years, black ginseng, a new type of processed ginseng product, has attracted the attention of scholars globally. Ginsenoside and ginseng polysaccharide, the main active substances of black ginseng, have been shown to carry curative effects for many diseases. This article focuses on the mechanism of their action in anti-inflammatory response, which is mainly divided into three aspects: activation of immune cells to exert immune regulatory response; participation in inflammatory response-related pathways and regulation of the expression level of inflammatory factors; effect on the metabolic activity of intestinal flora. This study identifies active anti-inflammatory components and an action mechanism of black ginseng showing multi-component, multi-target, and multi-channel characteristics, providing ideas and a basis for a follow-up in-depth study of its specific mechanism. 相似文献
32.
已有研究报道灵芝栽培生长的最适pH在中性偏酸环境,在碱性范围的生长及代谢情况鲜见报道。本研究主要探究广泛pH对灵芝液态发酵代谢物及其抗氧化活性的影响。采用摇瓶液态培养后分析代谢物中灵芝三萜、胞内外多糖、菌丝体蛋白及抗氧化活性等指标,系统比较灵芝菌丝体在pH值2-11的生长和代谢情况。研究结果表明,灵芝菌丝体生长、合成灵芝三萜、胞内多糖、30E胞外多糖、菌丝体蛋白和菌丝体水解氨基酸的最适pH值分别为10、3、2、7、2和2。对应结果分别为17.13 g/L、33.86 mg/g、72.73 mg/g、7.86 g/L、71.42 mg/g和107.10 mg/g。比对照分别提高28.5%、77.3%、22.4%、96.5%、97.1%和70.8%。胞内多糖组分1和组分2最高分子量均在初始pH 4,分别为1.016×108 g/mol和9.280×104 g/mol,胞外多糖组分1最高分子量在初始pH 10,为4.946×106 g/mol;对菌丝体的总抗氧化能力、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2- picrylhydrazyl,DPPH)自由基清除能力、羟自由基清除能力分析结果表明最佳的初始pH分别为3、7、9。本研究为液态发酵方式下灵芝生长及其代谢物定向调控发酵的工艺优化提供参考依据,同时发现灵芝菌丝体中优质蛋白及抗氧化活性可在功能性食品和化妆品领域推广应用。 相似文献
33.
In previous studies with tropical plant species, low root zone temperature (RZT) induced boron (B) deficiency, but it is not known if the same response to RZT will be expressed in temperate species, like oilseed rape, that are more tolerant of low temperature. The present experiments investigated the effect of RZT (10 and 20°C) on oilseed rape ( Brassica napus L. cv. Hyola 42) response to B in solution culture, in summer and winter. Regardless of canopy growth conditions, low RZT (10°C) promoted the partitioning of shoot B to the actively growing leaves, especially when B supply was low. However, low RZT did not significantly alter net B uptake rates or plant biomass. Low RZT decreased the shoot-to-root ratio, countering the effects of low B which increased it, leading to a decreased demand for B in the shoot at low RZT. At low B supply, B-deficiency symptoms appeared later at 10 than at 20°C, corresponding with higher B concentrations in the youngest fully opened leaves (YOLs) at 10°C RZT. Thus 10°C RZT increased the tolerance to low B supply. As a result, it is concluded that the effect of decreasing RZT on the responses of the temperate species, oilseed rape, to low B supply depends on whether the low RZT is above or below the optimal root temperature for growth. 相似文献
34.
本文研究TSH和forskolin对原代培养的猪甲状腺细胞[Ca~(2+)]_i和钙调蛋白的影响。结果表明,TSH可引起甲状腺细胞[Ca~(2+)]_1急性升高。此反应是剂量依赖关系,而与细胞外钙的存在与否无关。其反应性在细胞单层高于细胞是液,近汇合细胞单层高于汇合细胞单层。TSH作用3天,可使甲状腺细胞的钙调蛋白含量增高,此作用与TSH对甲状腺细胞数的影响无关。Forskolin对甲状腺细胞的[Ca~(2+)]_i和钙调蛋白均无明显的影响。 相似文献
35.
Summary The effect of protoplast-isolating enzymes on spontaneous fusion of maize protoplasts (Zea mays L. cv. Black Mexican Sweet) was investigated using a convenient ethidium bromide nuclear staining procedure. After 2–2.5 hour digestion in an enzyme solution containing 1% Cellulysin, 0.5% Rhozyme, and 0.02% Pectolyase Y-23, 50–75% of the protoplasts contained multiple nuclei. The cellulase Cellulysin was identified as the factor causing the spontaneous protoplast fusion; when Cellulysin was replaced by CELF cellulase, most protoplasts were uninucleate. Calcium and other components in the enzyme solution did not affect spontaneous fusion. Cellulysin also increased the percentage of multinucleate protoplasts from rice and asparagus suspensions. Presence of multiple nuclei might affect genetic manipulations involving protoplasts. 相似文献
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38.
Yiwen Liu Jianfang Gao Min Xu Qianqian Zhou Zhongxiao Zhang Jiaxin Ye Rui Li 《Journal of cellular and molecular medicine》2022,26(13):3616
Congenital heart disease (CHD) is the most common birth defect, affecting approximately 1% of live births. Genetic and environmental factors are leading factors to CHD, but the mechanism of CHD pathogenesis remains unclear. Circular RNAs (circRNAs) are kinds of endogenous non‐coding RNAs (ncRNAs) involved in a variety of physiological and pathological processes, especially in heart diseases. In this study, three significant differently expressed circRNA between maternal embryonic day (E) E13 and E17 was found by microarray assay. Among them, the content of circ‐RCCD increases with the development of heart and was enriched in primary cardiomyocytes of different species, which arouses our attention. Functional experiments revealed that inhibition of circ‐RCCD dramatically suppressed the formation of beating cell clusters, the fluorescence intensity of cardiac differentiation marker MF20, and the expression of the myocardial‐specific markers CTnT, Mef2c, and GATA4. Next, we found that circ‐RCCD was involved in cardiomyocyte differentiation through negative regulation of MyD88 expression. Further experiments proved that circ‐RCCD inhibited MyD88 levels by recruiting YY1 to the promoter of MyD88; circ‐RCCD inhibited nuclear translocation of YY1. These results reported that circ‐RCCD promoted cardiomyocyte differentiation by recruiting YY1 to the promoter of MyD88. And, this study provided a potential role and molecular mechanism of circ‐RCCD as a target for the treatment of CHD. 相似文献
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Aaron Mendez-Bermudez Liudmyla Lototska Melanie Pousse Florent Tessier Oliver Croce Chrysa
M Latrick Veronica Cherdyntseva Joe Nassour Jiang Xiaohua Yiming Lu Corinne Abbadie Sarantis Gagos Jing Ye Eric Gilson 《Nucleic acids research》2022,50(13):7493
Cellular senescence triggers various types of heterochromatin remodeling that contribute to aging. However, the age-related mechanisms that lead to these epigenetic alterations remain elusive. Here, we asked how two key aging hallmarks, telomere shortening and constitutive heterochromatin loss, are mechanistically connected during senescence. We show that, at the onset of senescence, pericentromeric heterochromatin is specifically dismantled consisting of chromatin decondensation, accumulation of DNA breakages, illegitimate recombination and loss of DNA. This process is caused by telomere shortening or genotoxic stress by a sequence of events starting from TP53-dependent downregulation of the telomere protective protein TRF2. The resulting loss of TRF2 at pericentromeres triggers DNA breaks activating ATM, which in turn leads to heterochromatin decondensation by releasing KAP1 and Lamin B1, recombination and satellite DNA excision found in the cytosol associated with cGAS. This TP53–TRF2 axis activates the interferon response and the formation of chromosome rearrangements when the cells escape the senescent growth arrest. Overall, these results reveal the role of TP53 as pericentromeric disassembler and define the basic principles of how a TP53-dependent senescence inducer hierarchically leads to selective pericentromeric dismantling through the downregulation of TRF2. 相似文献