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排序方式: 共有623条查询结果,搜索用时 109 毫秒
91.
92.
Leandar Litov Peicho Petkov Miroslav Rangelov Nevena Ilieva Elena Lilkova Nadezhda Todorova Elena Krachmarova Kristina Malinova Anastas Gospodinov Rossitsa Hristova Ivan Ivanov Genoveva Nacheva 《International journal of molecular sciences》2021,22(19)
Our objective is to reveal the molecular mechanism of the anti-inflammatory action of low-molecular-weight heparin (LMWH) based on its influence on the activity of two key cytokines, IFNγ and IL-6. The mechanism of heparin binding to IFNγ and IL-6 and the resulting inhibition of their activity were studied by means of extensive molecular-dynamics simulations. The effect of LMWH on IFNγ signalling inside stimulated WISH cells was investigated by measuring its antiproliferative activity and the translocation of phosphorylated STAT1 in the nucleus. We found that LMWH binds with high affinity to IFNγ and is able to fully inhibit the interaction with its cellular receptor. It also influences the biological activity of IL-6 by binding to either IL-6 or IL-6/IL-6Rα, thus preventing the formation of the IL-6/IL-6Rα/gp130 signalling complex. These findings shed light on the molecular mechanism of the anti-inflammatory action of LMWH and underpin its ability to influence favourably conditions characterised by overexpression of these two cytokines. Such conditions are not only associated with autoimmune diseases, but also with inflammatory processes, in particular with COVID-19. Our results put forward heparin as a promising means for the prevention and suppression of severe CRS and encourage further investigations on its applicability as an anti-inflammatory agent. 相似文献
93.
Oxidation of primary and secondary aliphatic and secondary benzylic alcohols into their corresponding aldehydes and ketones was achieved in good yields with palladium catalysts using air as the reoxidant of palladium. The use of palladacycle 1 resulted in higher yields and a faster reaction than the use of Pd(OAc)2 as the palladium source. 相似文献
94.
Kristina Dominko Ana Rastija Sandra Sobocanec Lea Vidatic Sarah Meglaj Andrea Lovincic Babic Birgit Hutter-Paier Alessio-Vittorio Colombo Stefan F. Lichtenthaler Sabina Tahirovic Silva Hecimovic 《International journal of molecular sciences》2021,22(24)
Niemann-Pick type C disease (NPC) is a rare inherited neurodegenerative disorder characterized by an accumulation of intracellular cholesterol within late endosomes and lysosomes due to NPC1 or NPC2 dysfunction. In this work, we tested the hypothesis that retromer impairment may be involved in the pathogenesis of NPC and may contribute to increased amyloidogenic processing of APP and enhanced BACE1-mediated proteolysis observed in NPC disease. Using NPC1-null cells, primary mouse NPC1-deficient neurons and NPC1-deficient mice (BALB/cNctr-Npc1m1N), we show that retromer function is impaired in NPC. This is manifested by altered transport of the retromer core components Vps26, Vps35 and/or retromer receptor sorLA and by retromer accumulation in neuronal processes, such as within axonal swellings. Changes in retromer distribution in NPC1 mouse brains were observed already at the presymptomatic stage (at 4-weeks of age), indicating that the retromer defect occurs early in the course of NPC disease and may contribute to downstream pathological processes. Furthermore, we show that cholesterol depletion in NPC1-null cells and in NPC1 mouse brains reverts retromer dysfunction, suggesting that retromer impairment in NPC is mechanistically dependent on cholesterol accumulation. Thus, we characterized retromer dysfunction in NPC and propose that the rescue of retromer impairment may represent a novel therapeutic approach against NPC. 相似文献
95.
Vu Thu Thuy Nguyen Lena Brücker Ann-Kathrin Volz Julia C. Baumgrtner Malena dos Santos Guilherme Francesco Valeri Helen May-Simera Kristina Endres 《International journal of molecular sciences》2021,22(24)
Neurodegenerative diseases such as Alzheimer’s disease (AD) have long been acknowledged as mere disorders of the central nervous system (CNS). However, in recent years the gut with its autonomous nervous system and the multitude of microbial commensals has come into focus. Changes in gut properties have been described in patients and animal disease models such as altered enzyme secretion or architecture of the enteric nervous system. The underlying cellular mechanisms have so far only been poorly investigated. An important organelle for integrating potentially toxic signals such as the AD characteristic A-beta peptide is the primary cilium. This microtubule-based signaling organelle regulates numerous cellular processes. Even though the role of primary cilia in a variety of developmental and disease processes has recently been recognized, the contribution of defective ciliary signaling to neurodegenerative diseases such as AD, however, has not been investigated in detail so far. The AD mouse model 5xFAD was used to analyze possible changes in gut functionality by organ bath measurement of peristalsis movement. Subsequently, we cultured primary enteric neurons from mutant mice and wild type littermate controls and assessed for cellular pathomechanisms. Neurite mass was quantified within transwell culturing experiments. Using a combination of different markers for the primary cilium, cilia number and length were determined using fluorescence microscopy. 5xFAD mice showed altered gut anatomy, motility, and neurite mass of enteric neurons. Moreover, primary cilia could be demonstrated on the surface of enteric neurons and exhibited an elongated phenotype in 5xFAD mice. In parallel, we observed reduced β-Catenin expression, a key signaling molecule that regulates Wnt signaling, which is regulated in part via ciliary associated mechanisms. Both results could be recapitulated via in vitro treatments of enteric neurons from wild type mice with A-beta. So far, only a few reports on the probable role of primary cilia in AD can be found. Here, we reveal for the first time an architectural altered phenotype of primary cilia in the enteric nervous system of AD model mice, elicited potentially by neurotoxic A-beta. Potential changes on the sub-organelle level—also in CNS-derived neurons—require further investigations. 相似文献
96.
97.
Knesting KM Hotchkiss PJ Macleod BA Marder SR Ginger DS 《Advanced materials (Deerfield Beach, Fla.)》2012,24(5):642-646
The interface between an organic semiconductor and a transparent conducting oxide is crucial to the performance of organic optoelectronics. We use microcontact printing to pattern pentafluorobenzyl phosphonic acid self-assembled monolayers (SAMs) on indium tin oxide (ITO). We obtain high-fidelity patterns with sharply defined edges and with large work function contrast (comparable to that obtained from phosphonic acid SAMs deposited from solution). 相似文献
98.
Although perceived criticism is relational, most theory and research concerns only relatives' criticism toward patients and not the converse. With a sample of 33 depressed patients and their spouses, we take a fully relational approach to criticism by testing an actor–partner interdependence model (Kenny, Kashy, & Cook, 2006). Patient intended criticism was especially strongly associated with depressive symptoms for wives, whereas patient perceived criticism was especially negatively related to depressive symptoms for husbands. Nondepressed partner intended criticism was positively related to patient depressive symptoms, but nondepressed wife perceived criticism was negatively related to husband depressive symptoms. The importance of including patient intended and partner perceived criticism as well as examining sex differences in models of criticism and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Gaëlle Boudry M. Kristina Hamilton Maciej Chichlowski Saumya Wickramasinghe Daniela Barile Karen M. Kalanetra David A. Mills Helen E. Raybould 《Journal of dairy science》2017,100(4):2471-2481
Obesity is characterized by altered gut homeostasis, including dysbiosis and increased gut permeability closely linked to the development of metabolic disorders. Milk oligosaccharides are complex sugars that selectively enhance the growth of specific beneficial bacteria in the gastrointestinal tract and could be used as prebiotics. The aim of the study was to demonstrate the effects of bovine milk oligosaccharides (BMO) and Bifidobacterium longum ssp. infantis (B. infantis) on restoring diet-induced obesity intestinal microbiota and barrier function defects in mice. Male C57/BL6 mice were fed a Western diet (WD, 40% fat/kcal) or normal chow (C, 14% fat/kcal) for 7 wk. During the final 2 wk of the study, the diet of a subgroup of WD-fed mice was supplemented with BMO (7% wt/wt). Weekly gavage of B. infantis was performed in all mice starting at wk 3, yet B. infantis could not be detected in any luminal contents when mice were killed. Supplementation of the WD with BMO normalized the cecal and colonic microbiota with increased abundance of Lactobacillus compared with both WD and C mice and restoration of Allobaculum and Ruminococcus levels to that of C mice. The BMO supplementation reduced WD-induced increase in paracellular and transcellular flux in the large intestine as well as mRNA levels of the inflammatory marker tumor necrosis factor α. In conclusion, BMO are promising prebiotics to modulate gut microbiota and intestinal barrier function for enhanced health. 相似文献
100.
Kristin Yaehne Amy Tekrony Aisling Clancy Yiota Gregoriou John Walker Kwin Dean Trinh Nguyen Amber Doiron Kristina Rinker Xiao Yu Jiang Sarah Childs David Cramb 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(18):3118-3127
Nanoparticles are increasingly used in medical applications such as drug delivery, imaging, and biodiagnostics, particularly for cancer. The design of nanoparticles for tumor delivery has been largely empirical, owing to a lack of quantitative data on angiogenic tissue sequestration. Using fluorescence correlation spectroscopy, the deposition rate constants of nanoparticles into angiogenic blood vessel tissue are determined. It is shown that deposition is dependent on surface charge. Moreover, the size dependency strongly suggests that nanoparticles are taken up by a passive mechanism that depends largely on geometry. These findings imply that it is possible to tune nanoparticle pharmacokinetics simply by adjusting nanoparticle size. 相似文献