Search results for "MEC"

Staining SDS-PAGE gels of skeletal matrices after western blot: a way to improve their sharpness.

2015

7 pages; International audience; Denaturing 1D electrophoresis on acrylamide gels - also referred as SDS-PAGE - is a classical technique for fractionating and visualizing the macromolecular constituents of matrices associated to calcified tissues. This technique has been widely used in association with the subsequent silver nitrate staining. But because matrices associated to calcified tissues are very often glycosylated and constituted of numerous polydisperse macromolecules, the obtained pattern is frequently 'smeary' and discrete bands, when present on the gel, are often blurred, thickened or totally masked by the polydisperse macromolecules. In this paper, we present a simple protocol t…

2019

The DNA-binding of the natural benzophenanthridine alkaloid chelerythrine (CHE) has been assessed by combining molecular modeling and optical absorption spectroscopy. Specifically, both double-helical (B-DNA) and G-quadruplex sequences—representative of different topologies and possessing biological relevance, such as telomeric or regulatory sequences—have been considered. An original multiscale protocol, making use of molecular dynamics (MD) simulations and quantum mechanics/molecular mechanics (QM/MM) calculations, allowed us to compare the theoretical and experimental circular dichroism spectra of the different DNA topologies, readily providing atomic-level details of the CHE–DNA binding…

Exercise Biomechanics and Physiology.

2021

Biomechanics was defined by Hatze in 1974 as the study of the movement of living things using the science of mechanics [...]

Collective behavior of quorum-sensing run-and-tumble particles in confinement

2016

We study a generic model for quorum-sensing bacteria in circular confinement. Every bacterium produces signaling molecules, the local concentration of which triggers a response when a certain threshold is reached. If this response lowers the motility then an aggregation of bacteria occurs, which differs fundamentally from standard motility-induced phase separation due to the long-ranged nature of the concentration of signal molecules. We analyze this phenomenon analytically and by numerical simulations employing two different protocols leading to stationary cluster and ring morphologies, respectively.

Antibacterial properties and reduction of MRSA biofilm with a dressing combining polyabsorbent fibres and a silver matrix

2016

Objective: This study was designed to evaluate the antibacterial activity of a wound dressing which combines polyacrylate fibres and a silver lipido-colloid matrix (UrgoClean Ag, silver polyabsorbent dressing), against biofilm of methicillin-resistant Staphylococcus aureus (MRSA). Method: Samples of silver polyabsorbent dressing and the neutral form of this dressing (UrgoClean) were applied to biofilms of MRSA formed on a collagen I-coated surface, cultured for 24 hours. Different exposure times were tested (1, 2, 4 and 7 days) without dressing change. The biofilm reduction was quantified by using culture methods and by confocal laser scanning microscopy experiments. Results: The applicatio…

Abstract C097: Pyrrolo[2′,3′:3,4]cyclohepta[1,2-d][1,2]oxazoles: A new class of antimitotic agents

2019

Abstract Tubulin-binding molecules constitute an important class of antineoplastic agents, with broad activity in both solid and hematologic malignancies. Oxazoles represent the core structure of many drug candidates with multiple targets, providing an attractive scaffold in medicinal chemistry. Diaryl[1,2]oxazoles have emerged as potent analogues of the antitubulin compound combretastatin A-4 (CA-4). Naphtylcombretastin and its derivatives incorporating the isoxazole moiety displayed potent cytotoxic effects and inhibition of tubulin polymerization. In particular, 5-(naphthalen-2-yl)-4-(TMP)-1,2-oxazole and 4-(naphthalen-2-yl)-5-(TMP)-1,2-oxazole showed the same inhibitory potency as napht…

Cohesive Model for the Simulation of Crack Initiation and Propagation in Mixed-Mode I/II in Composite Materials

2019

A cohesive element able to connect and simulate crack growth between independently modeled finite element subdomains with non-matching meshes is proposed and validated. The approach is based on penalty constraints and has several advantages over conventional FE techniques in disconnecting two regions of a model during crack growth. The most important is the ability to release portion of the interface that are smaller than the local finite element length. Thus, the growth of delamination is not limited to advancing by releasing nodes of the FE model, which is a limitation common to the methods found in the literature. Furthermore, it is possible to vary the penalty parameter within the cohes…

Data mining approaches to identify biomineralization related sequences.

2015

Proteomics is an efficient high throughput technique developed to identify proteins from a crude extract using sequence homology. Advances in Next Generation Sequencing (NGS) have led to increase knowledge of several non-model species. In the field of calcium carbonate biomineralization, the paucity of available sequences (such as the ones of mollusc shells) is still a bottleneck in most proteomic studies. Indeed, this technique needs proteins databases to find homology. The aim of this study was to perform different data mining approaches in order to identify novel shell proteins. To this end, we disposed of several publicly non-model molluscs databases. Previously identified molluscan she…

Topographic Independent Component Analysis reveals random scrambling of orientation in visual space

2017

Neurons at primary visual cortex (V1) in humans and other species are edge filters organized in orientation maps. In these maps, neurons with similar orientation preference are clustered together in iso-orientation domains. These maps have two fundamental properties: (1) retinotopy, i.e. correspondence between displacements at the image space and displacements at the cortical surface, and (2) a trade-off between good coverage of the visual field with all orientations and continuity of iso-orientation domains in the cortical space. There is an active debate on the origin of these locally continuous maps. While most of the existing descriptions take purely geometric/mechanistic approaches whi…

Harnessing mechanosensation in next generation cardiovascular tissue engineering

2020

The ability of the cells to sense mechanical cues is an integral component of ”social” cell behavior inside tissues with a complex architecture. Through ”mechanosensation” cells are in fact able to decrypt motion, geometries and physical information of surrounding cells and extracellular matrices by activating intracellular pathways converging onto gene expression circuitries controlling cell and tissue homeostasis. Additionally, only recently cell mechanosensation has been integrated systematically as a crucial element in tissue pathophysiology. In the present review, we highlight some of the current efforts to assess the relevance of mechanical sensing into pathology modeling and manufact…