Search results for "A2"
showing 10 items of 1101 documents
Development of an RNA-based kit for easy generation of TCR-engineered lymphocytes to control T-cell assay performance.
2018
Cell-based assays to monitor antigen-specific T-cell responses are characterized by their high complexity and should be conducted under controlled conditions to lower multiple possible sources of assay variation. However, the lack of standard reagents makes it difficult to directly compare results generated in one lab over time and across institutions. Therefore TCR-engineered reference samples (TERS) that contain a defined number of antigen-specific T cells and continuously deliver stable results are urgently needed. We successfully established a simple and robust TERS technology that constitutes a useful tool to overcome this issue for commonly used T-cell immuno-assays. To enable users t…
N-retinylidene-N-retinylethanolamine adduct induces expression of chronic inflammation cytokines in retinal pigment epithelium cells
2021
Blindness due to photoreceptor degeneration is observed in both genetic and acquired eye disorders. Long blue light exposure can contribute to increase levels of oxidative compounds within the retinal pigment epithelium (RPE), enhancing risk of retinal damage. In retina, reactive oxygen species contribute to the activation of inflammatory cascade. If chronic, this inflammatory response can result in photoreceptor death. Therefore, we investigated the effects of the endogenous adduct N-retinylidene-N-retinylethanolamine (A2E) on RPE cells, in order to identify the most dysregulated cytokines and their related inflammatory pathways. RPE cells were exposed to A2E and blue light for 3h and 6h. …
The Effect of Resveratrol on the Composition and State of Lipids and the Activity of Phospholipase A2 During the Excitation and Regeneration of Somat…
2019
It has been shown that in the somatic nerve's lipids, both during excitation and transection, changes occur with the composition of individual phospholipids and in phospholipids fatty acids, which changes the phase state of the myelin and nerve fiber axolemma lipid bilayer. A main contribution in the nerve degenerative processes is dependent on the composition phospholipid's fatty acid changes during the activation of both Ca2+-dependent and Ca2+-independent phospholipase A2 forms. At the same time, we studded changes in phosphoinisitol (PI) and diacylglycerol (DAG), which depend on the phosphoinositide cycle function during nerve excitation and degeneration processes. It was found that mye…
Regulation of yeast fatty acid desaturase in response to iron deficiency
2017
Unsaturated fatty acids (UFA) are essential components of phospholipids that greatly contribute to the biophysical properties of cellular membranes. Biosynthesis of UFAs relies on a conserved family of iron-dependent fatty acid desaturases, whose representative in the model yeast Saccharomyces cerevisiae is Ole1. OLE1 expression is tightly regulated to adapt UFA biosynthesis and lipid bilayer properties to changes in temperature, and in UFA or oxygen availability. Despite iron deficiency being the most extended nutritional disorder worldwide, very little is known about the mechanisms and the biological relevance of fatty acid desaturases regulation in response to iron starvation. In this re…
Analyzing the feasibility of time correlated spectral entropy for the assessment of neuronal synchrony
2016
In this paper, we study neuronal network analysis based on microelectrode measurements. We search for potential relations between time correlated changes in spectral distributions and synchrony for neuronal network activity. Spectral distribution is quantified by spectral entropy as a measure of uniformity/complexity and this measure is calculated as a function of time for the recorded neuronal signals, i.e., time variant spectral entropy. Time variant correlations in the spectral distributions between different parts of a neuronal network, i.e., of concurrent measurements via different microelectrodes, are calculated to express the relation with a single scalar. We demonstrate these relati…
Collective Cell Migration in a Fibrous Environment: A Hybrid Multiscale Modelling Approach
2021
International audience; The specific structure of the extracellular matrix (ECM), and in particular the density and orientation of collagen fibres, plays an important role in the evolution of solid cancers. While many experimental studies discussed the role of ECM in individual and collective cell migration, there are still unanswered questions about the impact of nonlocal cell sensing of other cells on the overall shape of tumour aggregation and its migration type. There are also unanswered questions about the migration and spread of tumour that arises at the boundary between different tissues with different collagen fibre orientations. To address these questions, in this study we develop …
Chronic myelogenous leukaemia exosomes modulate bone marrow microenvironment through activation of epidermal growth factor receptor
2016
Abstract Chronic myelogenous leukaemia (CML) is a clonal myeloproliferative disorder. Recent evidence indicates that altered crosstalk between CML and mesenchymal stromal cells may affect leukaemia survival; moreover, vesicles released by both tumour and non‐tumour cells into the microenvironment provide a suitable niche for cancer cell growth and survival. We previously demonstrated that leukaemic and stromal cells establish an exosome‐mediated bidirectional crosstalk leading to the production of IL8 in stromal cells, thus sustaining the survival of CML cells. Human cell lines used are LAMA84 (CML cells), HS5 (stromal cells) and bone marrow primary stromal cells; gene expression and protei…
Bacterial community structure along the subtidal sandy sediment belt of a high Arctic fjord (Kongsfjorden, Svalbard Islands)
2018
Open fjords are subject to contrasting environmental conditions, owing to meltwater glacial inputs, terrestrial runoff, and marine water mass exchanges, which are exacerbated by anthropogenic and climate perturbations. Following a slope-dependent water circulation, the subtidal sandy sediment belt regulates the convergent transport of nutrients downward the fjord depths, and the effective entrapment of suspended particles and microorganisms. In this study, we aimed at testing how glacial and seawater inputs may influence the bacterial community structure of subtidal sand deposits in the Kongsfjorden. Through total and viable cell counting and an amplicon sequencing approach, we found releva…
Blocking oestradiol synthesis pathways with potent and selective coumarin derivatives
2018
A comprehensive set of 3-phenylcoumarin analogues with polar substituents was synthesised for blocking oestradiol synthesis by 17-b-hydroxysteroid dehydrogenase 1 (HSD1) in the latter part of the sulphatase pathway. Five analogues produced 62% HSD1 inhibition at 5 mM and, furthermore, three of them produced 68% inhibition at 1 mM. A docking-based structure-activity relationship analysis was done to determine the molecular basis of the inhibition and the cross-reactivity of the analogues was tested against oestrogen receptor, aromatase, cytochrome P450 1A2, and monoamine oxidases. Most of the analogues are only modestly active with 17-b-hydroxysteroid dehydrogenase 2 – a requirement for lowe…
Photocatalytic Activity of Polymer Nanoparticles Modulates Intracellular Calcium Dynamics and Reactive Oxygen Species in HEK-293 Cells
2018
Optical modulation of living cells activity by light-absorbing exogenous materials is gaining increasing interest, due to the possibility both to achieve high spatial and temporal resolution with a minimally invasive and reversible technique and to avoid the need of viral transfection with light-sensitive proteins. In this context, conjugated polymers represent ideal candidates for photo-transduction, due to their excellent optoelectronic and biocompatibility properties. In this work, we demonstrate that organic polymer nanoparticles, based on poly(3-hexylthiophene) conjugated polymer, establish a functional interaction with an in vitro cell model (Human Embryonic Kidney cells, HEK-293). Th…