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排序方式: 共有500条查询结果,搜索用时 15 毫秒
401.
Omri Zveik Ariel Rechtman Nitzan Haham Irit Adini Tamar Canello Iris Lavon Livnat Brill Adi Vaknin-Dembinsky 《International journal of molecular sciences》2022,23(13)
Neuromyelitis optica (NMO) is a rare disease usually presenting with bilateral or unilateral optic neuritis with simultaneous or sequential transverse myelitis. Autoantibodies directed against aquaporin-4 (AQP4-IgG) are found in most patients. They are believed to cross the blood–brain barrier, target astrocytes, activate complement, and eventually lead to astrocyte destruction, demyelination, and axonal damage. However, it is still not clear what the primary pathological event is. We hypothesize that the interaction of AQP4-IgG and astrocytes leads to DNA damage and apoptosis. We studied the effect of sera from seropositive NMO patients and healthy controls (HCs) on astrocytes’ immune gene expression and viability. We found that sera from seropositive NMO patients led to higher expression of apoptosis-related genes, including BH3-interacting domain death agonist (BID), which is the most significant differentiating gene (p < 0.0001), and triggered more apoptosis in astrocytes compared to sera from HCs. Furthermore, NMO sera increased DNA damage and led to a higher expression of immunological genes that interact with BID (TLR4 and NOD-1). Our findings suggest that sera of seropositive NMO patients might cause astrocytic DNA damage and apoptosis. It may be one of the mechanisms implicated in the primary pathological event in NMO and provide new avenues for therapeutic intervention. 相似文献
402.
Sergio Quesada-Vzquez Caitlin Bone Shikha Saha Iris Triguero Marina Colom-Pellicer Gerard Aragons Falk Hildebrand Josep M. del Bas Antoni Caimari Naiara Beraza Xavier Escot 《International journal of molecular sciences》2022,23(22)
The gut is a selective barrier that not only allows the translocation of nutrients from food, but also microbe-derived metabolites to the systemic circulation that flows through the liver. Microbiota dysbiosis occurs when energy imbalances appear due to an unhealthy diet and a sedentary lifestyle. Dysbiosis has a critical impact on increasing intestinal permeability and epithelial barrier deterioration, contributing to bacterial and antigen translocation to the liver, triggering non-alcoholic fatty liver disease (NAFLD) progression. In this study, the potential therapeutic/beneficial effects of a combination of metabolic cofactors (a multi-ingredient; MI) (betaine, N-acetylcysteine, L-carnitine, and nicotinamide riboside) against NAFLD were evaluated. In addition, we investigated the effects of this metabolic cofactors’ combination as a modulator of other players of the gut-liver axis during the disease, including gut barrier dysfunction and microbiota dysbiosis. Diet-induced NAFLD mice were distributed into two groups, treated with the vehicle (NAFLD group) or with a combination of metabolic cofactors (NAFLD-MI group), and small intestines were harvested from all animals for histological, molecular, and omics analysis. The MI treatment ameliorated gut morphological changes, decreased gut barrier permeability, and reduced gene expression of some proinflammatory cytokines. Moreover, epithelial cell proliferation and the number of goblet cells were increased after MI supplementation. In addition, supplementation with the MI combination promoted changes in the intestinal microbiota composition and diversity, as well as modulating short-chain fatty acids (SCFAs) concentrations in feces. Taken together, this specific combination of metabolic cofactors can reverse gut barrier disruption and microbiota dysbiosis contributing to the amelioration of NAFLD progression by modulating key players of the gut-liver axis. 相似文献
403.
Adjmal Ghaur Felix Pfeiffer Diddo Diddens Christoph Peschel Iris Dienwiebel Leilei Du Laurin Profanter Matthias Weiling Martin Winter Tobias Placke Sascha Nowak Masoud Baghernejad 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(44):2302486
Effective electrolyte compositions are of primary importance in raising the performance of lithium-ion batteries (LIBs). Recently, fluorinated cyclic phosphazenes in combination with fluoroethylene carbonate (FEC) have been introduced as promising electrolyte additives, which can decompose to form an effective dense, uniform, and thin protective layer on the surface of electrodes. Although the basic electrochemical aspects of cyclic fluorinated phosphazenes combined with FEC were introduced, it is still unclear how these two compounds interact constructively during operation. This study investigates the complementary effect of FEC and ethoxy(pentafluoro)cyclotriphosphazene (EtPFPN) in aprotic organic electrolyte in LiNi0.5Co0.2Mn0.3O ∥ SiOx/C full cells. The formation mechanism of lithium ethyl methyl carbonate (LEMC)-EtPFPN interphasial intermediate products and the reaction mechanism of lithium alkoxide with EtPFPN are proposed and supported by Density Functional Theory calculations. A novel property of FEC is also discussed here, called molecular-cling-effect (MCE). To the best knowledge, the MCE has not been reported in the literature, although FEC belongs to one of the most investigated electrolyte additives. The beneficial MCE of FEC toward the sub-sufficient solid-electrolyte interphase forming additive compound EtPFPN is investigated via gas chromatography-mass spectrometry, gas chromatography high resolution-accurate mass spectrometry, in situ shell-isolated nanoparticle-enhanced Raman spectroscopy, and scanning electron microscopy. 相似文献
404.
Christos Bontzolis Iris Plioni Dimitra Dimitrellou Konstantina Boura Maria Kanellaki Poonam S. Nigam Athanasios Koutinas 《International Journal of Food Science & Technology》2022,57(8):5155-5163
This work evaluates the antimicrobial activity of the fractionated aqueous extract obtained from the aerial parts of aniseed. Fifteen fractions were collected by column chromatography using ethanol and water as mobile phases. All fractions were tested as potential antimicrobial agents against three common food-spoilage microorganisms: a yeast (Saccharomyces cerevisiae), a mold (Aspergillus awamori) and a bacterium (Lactobacillus delbrueckii subsp. bulgaricus). Fraction 2 exhibited the highest antimicrobial activity in both types of susceptibility test, and therefore, it was further studied for the identification of bioactive compounds. GC-MS analysis of Fraction 2 revealed the presence of threo-Anethole glycol. Based on laboratory-scale experiments, a process flowsheet for potential industrial-scale application is proposed combined with a techno-economic feasibility report. Fraction 2 with the detected compound threo-Anethole glycol showed promising results encouraging the attempts for industrial-scale application of antimicrobial compounds produced from aniseed. 相似文献
405.
Okke Melse Dr. Samuel Sutiono Magdalena Haslbeck Prof. Gerhard Schenk Prof. Iris Antes Prof. Volker Sieber 《Chembiochem : a European journal of chemical biology》2022,23(10):e202200088
The FeS cluster-dependent dihydroxyacid dehydratases (DHADs) and sugar acid-specific dehydratases (DHTs) from the ilvD/EDD superfamily are key enzymes in the bioproduction of a wide variety of chemicals. We analyzed [2Fe−2S]-dependent dehydratases in silico and in vitro, deduced functionally relevant sequence, structure, and activity relationships within the ilvD/EDD superfamily, and we propose a new classification based on their evolutionary relationships and substrate profiles. In silico simulations and analyses identified several key positions for specificity, which were experimentally investigated with site-directed and saturation mutagenesis. We thus increased the promiscuity of DHAD from Fontimonas thermophila (FtDHAD), showing >10-fold improved activity toward D-gluconate, and shifted the substrate preference of DHT from Paralcaligenes ureilyticus (PuDHT) toward shorter sugar acids (recording a six-fold improved activity toward the non-natural substrate D-glycerate). The successful elucidation of the role of important active site residues of the ilvD/EDD superfamily will further guide developments of this important biocatalyst for industrial applications. 相似文献
406.
Barbara Eyermann Maximilian Meixner Prof. Dr. Heike Brötz-Oesterhelt Prof. Dr. Iris Antes Prof. Dr. Stephan A. Sieber 《Chembiochem : a European journal of chemical biology》2020,21(1-2):235-240
Caseinolytic protease P (ClpP) is a tetradecameric peptidase that assembles with chaperones such as ClpX to gain proteolytic activity. Acyldepsipeptides (ADEPs) are small-molecule mimics of ClpX that bind into hydrophobic pockets on the apical site of the complex, thereby activating ClpP. Detection of ClpP has so far been facilitated with active-site-directed probes which depend on the activity and oligomeric state of the complex. To expand the scope of ClpP labeling, we took a stepwise synthetic approach toward customized ADEP photoprobes. Structure–activity relationship studies with small fragments and ADEP derivatives paired with modeling studies revealed the design principles for suitable probe molecules. The derivatives were tested for activation of ClpP and subsequently applied in labeling studies of the wild-type peptidase as well as enzymes bearing mutations at the active site and an oligomerization sensor. Satisfyingly, the ADEP photoprobes provided a labeling readout of ClpP independent of its activity and oligomeric state. 相似文献
407.
408.
We use data from a representative sample of adult Californians (N = 1500) to examine the relation between information and sociodemographic factors to the willingness to adopt recycled water in 10 different applications. We find that direct consumption or skin contact with recycled water stirs the strongest resistance. We conducted a randomized experiment to test how respondents would react to learning that there is large, existing, indirect potable use program in Orange County. While both messages boost support for almost all uses of recycled water, respondents still resist drinking, bathing and cooking with it. Contrary to some previous findings, the response to both information cues generally does not appear to depend upon level of education. 相似文献
409.