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91.
Pia Fahlbusch Aleksandra Nikolic Sonja Hartwig Sylvia Jacob Ulrike Kettel Cornelia Kllmer Hadi Al-Hasani Stefan Lehr Dirk Müller-Wieland Birgit Knebel Jrg Kotzka 《International journal of molecular sciences》2022,23(12)
Alterations in mitochondrial function are an important control variable in the progression of metabolic dysfunction-associated fatty liver disease (MAFLD), while also noted by increased de novo lipogenesis (DNL) and hepatic insulin resistance. We hypothesized that the organization and function of a mitochondrial electron transport chain (ETC) in this pathologic condition is a consequence of shifted substrate availability. We addressed this question using a transgenic mouse model with increased hepatic insulin resistance and DNL due to constitutively active human SREBP-1c. The abundance of ETC complex subunits and components of key metabolic pathways are regulated in the liver of these animals. Further omics approaches combined with functional assays in isolated liver mitochondria and primary hepatocytes revealed that the SREBP-1c-forced fatty liver induced a substrate limitation for oxidative phosphorylation, inducing enhanced complex II activity. The observed increased expression of mitochondrial genes may have indicated a counteraction. In conclusion, a shift of available substrates directed toward activated DNL results in increased electron flows, mainly through complex II, to compensate for the increased energy demand of the cell. The reorganization of key compounds in energy metabolism observed in the SREBP-1c animal model might explain the initial increase in mitochondrial function observed in the early stages of human MAFLD. 相似文献
92.
Vadim E. Filatov Dmitrii A. Iuzabchuk Viktor A. Tafeenko Yuri K. Grishin Vitaly A. Roznyatovsky Dmitrii A. Lukianov Yulia A. Fedotova Maxim A. Sukonnikov Dmitry A. Skvortsov Nikolai V. Zyk Elena K. Beloglazkina 《International journal of molecular sciences》2022,23(12)
In this work, we present the first synthesis of dispirooxindole-β-lactams employing optimized methodology of one-pot Staudinger ketene-imine cycloaddition with N-aryl-2-oxo-pyrrolidine-3-carboxylic acids as the ketene source. Spiroconjugation of indoline-2-one with β-lactams ring is considered to be able to provide stabilization and wide scope of functionalization to resulting scaffolds. The dispipooxindoles obtained demonstrated medium cytotoxicity in the MTT test on A549, MCF7, HEK293, and VA13 cell lines, and one of the compounds demonstrated antibacterial activity against E. coli strain LPTD. 相似文献
93.
Huijie Zhao Huiyang Liu Yihan Yang Honggang Wang 《International journal of molecular sciences》2022,23(11)
Pyroptosis is a programmed cell death caused by inflammasomes, which can detect cell cytosolic contamination or disturbance. In pyroptosis, caspase-1 or caspase-11/4/5 is activated, cleaving gasdermin D to separate its N-terminal pore-forming domain (PFD). The oligomerization of PFD forms macropores in the membrane, resulting in swelling and membrane rupture. According to the different mechanisms, pyroptosis can be divided into three types: canonical pathway-mediated pyroptosis, non-canonical pathway-mediated pyroptosis, and caspase-3-induced pyroptosis. Pyroptosis has been reported to play an important role in many tissues and organs, including the liver. Autophagy is a highly conserved process of the eukaryotic cell cycle. It plays an important role in cell survival and maintenance by degrading organelles, proteins and macromolecules in the cytoplasm. Therefore, the dysfunction of this process is involved in a variety of pathological processes. In recent years, autophagy and pyroptosis and their interactions have been proven to play an important role in various physiological and pathological processes, and have gradually attracted more and more attention to become a research hotspot. Therefore, this review summarized the role of autophagy and pyroptosis in liver disorders, and analyzed the related mechanism to provide a basis for future research. 相似文献
94.
目的 研发一款低热量、可作为代餐食品的薏仁红豆面包,并对其配方进行优化。方法 在单因素实验基础上进行Box-Behnken响应面优化实验,获得最佳配方,并对其质构特性及有机酸种类、含量进行分析。结果 红豆添加量13.50%、薏仁米添加量13.60%、高粉添加量41.00%、酵母添加量0.75%时,所得代餐面包的感官评分为82.33,与预测值82.81相近,并高于传统红豆面包。与传统红豆面包相比,薏仁红豆面包的弹性、内聚性、回复性较高。薏仁红豆面包检测出乳酸、乙酸等6种有机酸,其种类及总含量均高于传统红豆面包。结论 通过优化配方制得的产品结构松紧适中,口感较好,微酸并带有薏仁米的香味,低脂、低热量且富含膳食纤维,其加工条件简单,适于工业化生产,为薏仁米深加工开辟了新途径。 相似文献
95.
由丙烯两步氧化法生产丙烯酸的工艺中 ,主要问题在于找到选择性及转化率较好的 ,污染较小的催化剂。本文论述了 P Mo系杂多酸催化剂的性质对催化活性的影响 相似文献
96.
缓蚀阻垢剂HZ-X2的合成、性质及应用 总被引:2,自引:0,他引:2
中原文留油田油井含水高于85%,采出水中CO2与HCO3^-构成弱酸性缓冲体系,腐蚀性和结垢性很强,油井、集输和注水系统既出现腐蚀,又发生结垢。针对该油田研制并生产了新型缓蚀阻垢剂HZ-X2。简介了合成方法及产品技术性能,讨论了缓蚀和阻垢机理,详述了室内测试结果,简介了现场试验和应用情况。该剂由缓蚀成份咪唑啉及其衍生物、阻垢成份膦基丙烯酸-马来酸(酐)共聚物及溶剂制成,易溶于水,可溶或分散于油,不增加原油的乳化。在室内测试中,加量>100mg/L时在65℃采出水中的静态缓蚀剂>75%,在70℃油水混合液(30:70)中的动态缓蚀率>70%。加量≥20mg/L时,在75℃采出水中对Ca、Mg垢的阻垢率>84%。在现场试验中,从1口油井油套环空按产水量加入该剂100mg/L,在20天内使采出水中含铁量下降,腐蚀速率降至接近0.07mm/a。在文留油田现场应用中,不同油井加入适量药剂(60-100mg/L),加药周期一般15d左右,采出水平均腐蚀速率由0.408mm/a降至0.075mm/a,结垢速率由3-7mm/a降至0.121mm/a。表3。 相似文献
97.
将肉豆蔻酸甲酯(C14)、棕榈酸甲酯(C16)、硬脂酸甲酯(C18)、油酸甲酯(C18:1)、亚麻油酸甲酯(C18:2)及蓖麻油酸甲酯(C 18:1OH)添加至柴油中,基于Materials Studio软件建立酯/正十四烷在铁表面吸附构型,分析含酯油膜的能量构成。结果表明:对于C14酯/正十四烷混合物,随着酯体积分数增加,油膜的吸附能大幅增加,而内聚能总体差异较小;对于5%(体积分数)酯/正十四烷混合物,含不同酯油膜的吸附能总体上较为接近,但内聚能随着碳链长度、不饱和程度及极性基团等因素变化较大,其由大到小的顺序为C18:1OH、C18:2、C18:1、C18、C16、C14。对比酯体积分数与组分引起的油膜吸附能变化可见,酯体积分数是更重要的因子,但酯组分变化可引起内聚能显著的差异。酯体积分数增加和酯组分改变均为提升低硫柴油润滑性能的有效措施。 相似文献
98.
利用相对论电磁粒子模拟程序研究了超强激光与等离子体相互作用过程中产生的自生磁场和电子热输运特性。讨论了自生磁场产生机制和非线性饱和过程。给出了自生磁场的线性增长率和各向异性参数之间的函数关系,用Spitzer-Harm理论分析了电子热传导中能量的运输情况,观察到由激光的非等方加热引起的电子纵向加热现象。细致研究这些过程对更好的理解快点火物理中自生磁场的产生、超热电子热输运等过程有重要意义。 相似文献
99.
Agata Kaczmarek Anna Katarzyna Wroska Michalina Kazek Mieczysawa Irena Bogu 《International journal of molecular sciences》2022,23(9)
The food flavour additive octanoic acid (C8:0) is also a metabolite of the entomopathogenic fungus Conidiobolus coronatus, which efficiently infects and rapidly kills Galleria mellonella. GC-MS analysis confirmed the presence of C8:0 in insecticidal fraction FR3 extracted from C. coronatus filtrate. Topical administration of C8:0 had a dose-dependent effect on survival rates of larvae but not on pupation or adult eclosion times of the survivors. Topically applied C8:0 was more toxic to adults than larvae (LD100 for adults 18.33 ± 2.49 vs. 33.56 ± 2.57 µg/mg of body mass for larvae). The administration of C8:0 on the cuticle of larvae and adults, in amounts corresponding to their LD50 and LD100 doses, had a considerable impact on the two main defense systems engaged in protecting against pathogens, causing serious changes in the developmental-stage-specific profiles of free fatty acids (FFAs) covering the cuticle of larvae and adults and damaging larval hemocytes. In vitro cultures of G. mellonella hemocytes, either directly treated with C8:0 or taken from C8:0 treated larvae, revealed deformation of hemocytes, disordered networking, late apoptosis, and necrosis, as well as caspase 1–9 activation and elevation of 8-OHdG level. C8:0 was also confirmed to have a cytotoxic effect on the SF-9 insect cell line, as determined by WST-1 and LDH tests. 相似文献
100.
Celine Stoica Adilson Kleber Ferreira Kayleigh Hannan Marica Bakovic 《International journal of molecular sciences》2022,23(9)
Phospholipids represent a crucial component for the structure of cell membranes. Phosphatidylcholine and phosphatidylethanolamine are two phospholipids that comprise the majority of cell membranes. De novo biosynthesis of phosphatidylcholine and phosphatidylethanolamine occurs via the Kennedy pathway, and perturbations in the regulation of this pathway are linked to a variety of human diseases, including cancer. Altered phosphatidylcholine and phosphatidylethanolamine membrane content, phospholipid metabolite levels, and fatty acid profiles are frequently identified as hallmarks of cancer development and progression. This review summarizes the research on how phospholipid metabolism changes over oncogenic transformation, and how phospholipid profiling can differentiate between human cancer and healthy tissues, with a focus on colorectal cancer, breast cancer, and non-small cell lung cancer. The potential for phospholipids to serve as biomarkers for diagnostics, or as anticancer therapy targets, is also discussed. 相似文献