Search results for "Mine"
showing 10 items of 20410 documents
Guanosine-5'-Monophosphate Polyamine Hybrid Hydrogels: Enhanced Gel Strength Probed by z-Spectroscopy.
2017
The self-assembling tendencies of guanosine-5'-monophosphate (GMP) can be drastically increased using polyamines, with potential applications in the production of biocompatible smart materials, as well as for the design of anti-tumoral drugs based on G-quadruplex stabilization. Results from scanning electron microscopy (SEM), wide angle X-ray scattering (WAXS), rheology and nuclear magnetic resonance (NMR) z-spectroscopy studies are presented.
Nanoscale strain-engineering and optics of quantum emitters in a two-dimensional semiconductor
2017
We present deterministic fabrication of a two-dimensional lattice of quantum emitters in an atomically thin semiconductor. Resonant laser spectroscopy of these emitters reveals localized exciton states that exhibit stable, bright and high-purity single photon emission.
Chemical characterization of a variety of cold-pressed gourmet oils available on the Brazilian market
2018
Different specialty extra virgin oils, produced by cold-pressing fruits/nuts (olive, pequi, palm, avocado, coconut, macadamia and Brazil nut) and seeds (grapeseed and canola), and retailed in the Brazilian region of Minas Gerais, were chemically characterized. Specifically, for each type of oil, the fatty acid composition was elucidated by GC-FID, the contents of selected polyphenols and squalene were determined respectively by UHPLC-MS and UHPLC-PDA, whereas minerals were explored by means of ICP-MS. Olive oil was confirmed to have the highest MUFA content due to a valuable level of oleic acid, while oils from grapeseed, Brazil nut and canola were marked by nutritionally important PUFA lev…
Opposite Effects of Mechanical Action of Fluid Flow on Proangiogenic Factor Secretion From Human Adipose-Derived Stem Cells With and Without Oxidativ…
2017
Mechanical forces, hypoxia, and oxidative stress contribute to skin renewal, perfusion, and wound healing, but how are they regulating subcutaneous adipose-derived stem cells (ASCs) in the inflammatory microenvironment associated to skin repair and disorders is unknown. In this study, ASCs were isolated from lipoaspirate samples from plastic surgery patients, primary cultured and their differentiation and secretion of a panel of cytokines with pronounced effects on skin repair and angiogenesis were studied under mechanical stimulation by intermittent fluid flow, 1% hypoxia and oxidative stress by glutathione (GSH) depletion with buthionine sulfoximine (BSO) treatment. Mechanical action of f…
ERK1/2 activation in human taste bud cells regulates fatty acid signaling and gustatory perception of fat in mice and humans
2016
Obesity is a major public health problem. An in-depth knowledge of the molecular mechanisms of oro-sensory detection of dietary lipids may help fight it. Humans and rodents can detect fatty acids via lipido-receptors, such as CD36 and GPR120. We studied the implication of the MAPK pathways, in particular, ERK1/2, in the gustatory detection of fatty acids. Linoleic acid, a dietary fatty acid, induced via CD36 the phosphorylation of MEK1/2-ERK1/2-ETS-like transcription factor-1 cascade, which requires Fyn-Src kinase and lipid rafts in human taste bud cells (TBCs). ERK1/2 cascade was activated by Ca2+ signaling via opening of the calcium-homeostasis modulator-1 (CALHM1) channel. Furthermore, f…
Social defeat stress: mechanisms underlying the increase in rewarding effects of drugs of abuse
2018
Social interaction is known to be the main source of stress in human beings, which explains the translational importance of this research in animals. Evidence reported over the last decade has revealed that, when exposed to social defeat experiences (brief episodes of social confrontations during adolescence and adulthood), the rodent brain undergoes remodeling and functional modifications, which in turn lead to an increase in the rewarding and reinstating effects of different drugs of abuse. The mechanisms by which social stress cause changes in the brain and behavior are unknown, and so the objective of this review is to contemplate how social defeat stress induces longlasting consequence…
Regulating T-cell differentiation through the polyamine spermidine
2021
Background The cross-talk between the host and its microbiota plays a key role in the promotion of health. The production of metabolites such as polyamines by intestinal-resident bacteria is part of this symbiosis shaping host immunity. The polyamines putrescine, spermine, and spermidine are abundant within the gastrointestinal tract and might substantially contribute to gut immunity. Objective We aimed to characterize the polyamine spermidine as a modulator of T-cell differentiation and function. Methods Naive T cells were isolated from wild-type mice or cord blood from healthy donors and submitted to polarizing cytokines, with and without spermidine treatment, to evaluate CD4+ T-cell diff…
Interactions of human P-glycoprotein transport substrates and inhibitors at the drug binding domain: Functional and molecular docking analyses
2015
Rhodamine 123 (R123) transport substrate sensitizes P-glycoprotein (P-gp) to inhibition by compound 2c (cis-cis) N,N-bis(cyclohexanolamine)aryl ester isomer in a concentration-dependent manner in human MDR1-gene transfected mouse T-lymphoma L5178 cells as shown previously. By contrast, epirubicin (EPI) concentration changes left unaltered 2c IC50 values of EPI efflux. To clarify this discrepancy, defined molecular docking (DMD) analyses of 12 N,N-bis(cyclohexanolamine)aryl esters, the highly flexible aryl ester analog 4, and several P-gp substrate/non-substrate inhibitors were performed on human P-gp drug- or nucleotide-binding domains (DBD or NBD). DMD measurements yielded lowest binding e…
Correlation between octopaminergic signalling and foraging task specialisation in honeybees
2020
Regulation of pollen and nectar foraging in honeybees is linked to differences in the sensitivity to the reward. Octopamine (OA) participates in the processing of reward-related information in the bee brain, being a candidate to mediate and modulate the division of labour among pollen and nectar foragers. Here we tested the hypothesis that OA affects the resource preferences of foragers. We first investigated whether oral administration of OA is involved in the transition from nectar to pollen foraging. We quantified the percentage of OA-treated bees that switched from a sucrose solution to a pollen feeder when the sugar concentration was decreased experimentally. We also evaluated if feedi…
Hyperforin Potentiates Antidepressant-Like Activity of Lanicemine in Mice
2018
International audience; N-methyl-D-aspartate receptor (NMDAR) modulators induce rapid and sustained antidepressant like-activity in rodents through a molecular mechanism of action that involves the activation of Ca2+ dependent signaling pathways. Moreover, ketamine, a global NMDAR antagonist is a potent, novel, and atypical drug that has been successfully used to treat major depressive disorder (MDD). However, because ketamine evokes unwanted side effects, alternative strategies have been developed for the treatment of depression. The objective of the present study was to determine the antidepressant effects of either a single dose of hyperforin or lanicemine vs. their combined effects in m…