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961.
Servadio Simone Zanetti Renato 《Journal of Optimization Theory and Applications》2021,191(2-3):459-485
Journal of Optimization Theory and Applications - The nonlinear filtering problem plays a fundamental role in multiple space-related applications. This paper offers a new filtering technique that... 相似文献
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963.
Dr. Luis Martínez-Crespo Dr. Sarah H. Hewitt Dr. Nicola Alessandro De Simone Prof. Vladimír Šindelář Prof. Anthony P. Davis Dr. Stephen Butler Dr. Hennie Valkenier 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(26):7367-7375
Anion receptors can be used to transport ions across lipid bilayers, which has potential for therapeutic applications. Synthetic bicarbonate transporters are of particular interest, as defects in transmembrane transport of bicarbonate are associated with various diseases. However, no convenient method exists to directly observe bicarbonate transport and study the mechanisms involved. Here, an assay is presented that allows the kinetics of bicarbonate transport into liposomes to be monitored directly and with great sensitivity. The assay utilises an encapsulated europium(III) complex, which exhibits a large increase in emission intensity upon binding bicarbonate. Mechanisms involving CO2 diffusion and the dissipation of a pH gradient are shown to be able to lead to an increase in bicarbonate concentration within liposomes, without transport of the anion occurring at all. By distinguishing these alternative mechanisms from actual bicarbonate transport, this assay will inform the future development of bicarbonate transporters. 相似文献
964.
Lucia Recinella Annalisa Chiavaroli Viviana di Giacomo Marco Daniel Antolini Alessandra Acquaviva Sheila Leone Luigi Brunetti Luigi Menghini Gunes Ak Gokhan Zengin Simonetta Cristina Di Simone Claudio Ferrante Giustino Orlando 《Molecules (Basel, Switzerland)》2021,26(1)
Tanacetum parthenium (feverfew) has traditionally been employed as a phytotherapeutic remedy in the treatment of migraine. In this study, a commercial T. parthenium water extract was investigated to explore its anti-inflammatory and neuromodulatory effects. Isolated mouse cortexes were exposed to a K+ 60 mM Krebs-Ringer buffer and treated with T. parthenium water extract. The prostaglandin E2 (PGE2) level, brain-derived neurotrophic factor (BDNF), interleukin-10 (IL-10), and IL-1β gene expression were evaluated in the cortex. The effects on dopamine (DA) release and dopamine transporter (DAT) gene expression were assayed in hypothalamic HypoE22 cells. A bioinformatics analysis was conducted to further investigate the mechanism of action. The extract was effective in reducing cortex PGE2 release and IL-1β gene expression. In the same experimental system, IL-10 and BDNF gene expressions increased, and in HypoE22 cells, the extract decreased the extracellular dopamine level and increased the DAT gene expression due to the direct interaction of parthenolide with the DAT. Overall, the present findings highlight the efficacy of T. parthenium water extract in controlling the inflammatory pathways that occur during cortical-spreading depression. Additionally, the inhibition of the hypothalamic DA release observed in this study further supports the role of dopaminergic pathways as key targets for novel pharmacological approaches in the management of migraine attacks. 相似文献
965.
Sapna Gahlot Alessandro Gradone Prof. Dr. Myriam Roy Dr. Michel Giorgi Simone Conti Prof. Dr. Paola Ceroni Dr. Marco Villa Prof. Dr. Marc Gingras 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(46):e202200797
The synthesis of regioisomeric asterisks ( 5 ) and ( 6 ) incorporating a benzene core with six 1-naphthylthio or six 2-naphthylthio arms are reported in search for new materials with optoelectronic properties. The consequences on the extension of a π system surrounding a persulfurated benzene core provide a new avenue to study the structural, photophysical, and chemical properties of such family of all-organic phosphors. It also diverts the persulfuration mechanism after two radical cyclizations for making a [5]dithiohelicene by-product ( 7 ) and favors dynamic sulfur component exchange reactions surrounding the core. These exchanges convert asterisks ( 5 ) and ( 6 ), non-phosphorescent at 20 °C to the highly phosphorescent ( 4 ) (ϕ ∼100 %, solid state at 20 °C). For asterisks ( 5 ) and ( 6 ), the absence of the typical phosphorescence of the per(phenylthio)benzene core in the solid state at 20 °C and the presence of a weak naphthalene-based phosphorescence at 77 K is attributed to an energy transfer from the triplet state of the persulfurated benzene core to the outer naphthalene moieties, resulting in an antenna system. 相似文献
966.
Journal of Statistical Physics - A streamlined derivation of the Kac–Ward formula for the planar Ising model’s partition function is presented and applied in relating the kernel of the... 相似文献
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Barbara Turchi Simone Mancini Luisa Pistelli Basma Najar 《Natural product research》2019,33(10):1509-1513
Fourteen Staphylococcus aureus wild strains were stressed with sub-inhibitory concentration of five essential oils: Leptospermum scoparium (manuka), Origanum majorana (marjoram), Origanum vulgare (oregano), Satureja montana (winter savoury) and Thymus vulgaris (thyme). Antibiotics susceptibility profiles of the strains were determined by agar disk diffusion method before and after EOs treatment. The following antibiotics were employed: amoxicillin-clavulanic acid, amikacin, ampicillin, amoxicillin, aztreonam, ceftazidime, cephalothin, ciprofloxacin, colistin, cefotaxime, doxycycline, enrofloxacin, erythromycin, gentamicin, cephalexin, neomycin, piperacillin, rifampin, streptomycin, trimethoprim-sulphamethoxazole, tetracycline and tobramycin. Before EOs treatment, strains were susceptible to all antibiotics except for aztreonam and colistin. After exposure to sub-inhibitory EOs concentration of manuka, marjoram and oregano, several modifications in antibiotics susceptibility profiles were detected. Conversely, few modifications were induced by winter savoury and thyme EOs. Moreover, occurrence of resistances seems uncorrelated with drug classes as low concentration of EO could induce phenotypic changes in susceptible bacteria leading to antibiotic resistance phenomena. 相似文献
970.