Search results for "Biomimetics"
showing 10 items of 54 documents
Visualization of RNA-Quadruplexes in Live Cells
2015
Visualization of DNA and RNA quadruplex formation in human cells was demonstrated recently with different quadruplex-specific antibodies. Despite the significant interest in these immunodetection approaches, dynamic detection of quadruplex in live cells remains elusive. Here, we report on NaphthoTASQ (N-TASQ), a next-generation quadruplex ligand that acts as a multiphoton turn-on fluorescent probe. Single-step incubation of human and mouse cells with N-TASQ enables the direct detection of RNA-quadruplexes in untreated cells (no fixation, permeabilization or mounting steps), thus offering a unique, unbiased visualization of quadruplexes in live cells.
Dynamics of Pattern Formation in Biomimetic Systems
2008
This paper is an attempt to conceptualize pattern formation in self-organizing systems and, in particular, to understand how structures, oscillations or waves arise in a steady and homogenous environment, a phenomenon called symmetry breaking. The route followed to develop these ideas was to couple chemical oscillations produced by Belousov-Zhabotinsky reaction with confined reaction environments, the latter being an essential requirement for any process of Life. Special focus was placed on systems showing organic or lipidic compartments, which represent more reliable biomimetic matrices.
Biomimetic synthesis of the tumor-associated (2,3)-sialyl-T antigen and its incorporation into glycopeptide antigens from the mucins MUC1 and MUC4.
2004
Glycoproteins on epithelial tumor cells often exhibit aberrant glycosylation profiles. The incomplete formation of the glycan side chains resulting from a down-regulated glucosamine transfer and a premature sialylation results in additional peptide epitopes, which become accessible to the immune system in mucin-type glycoproteins. These cancer-specific structure alterations are considered to be a promising basis for selective immunological attack on tumor cells. Among the tumor-associated saccharide antigens, the (2,3)-sialyl-T antigen has been identified as the most abundant glycan, found in several different carcinoma cell lines. According to a linear biomimetic strategy, the (2,3)-sialyl…
Biologically inspired information processing and synchronization in ensembles of non-identical threshold-potential nanostructures.
2013
Nanotechnology produces basic structures that show a significant variability in their individual physical properties. This experimental fact may constitute a serious limitation for most applications requiring nominally identical building blocks. On the other hand, biological diversity is found in most natural systems. We show that reliable information processing can be achieved with heterogeneous groups of non-identical nanostructures by using some conceptual schemes characteristic of biological networks (diversity, frequency-based signal processing, rate and rank order coding, and synchronization). To this end, we simulate the integrated response of an ensemble of single-electron transisto…
Inverse Tone Mapping Based upon Retina Response
2014
International audience; The development of high dynamic range (HDR) display arouses the research of inverse tone mapping methods, which expand dynamic range of the low dynamic range (LDR) image to match that of HDR monitor. This paper proposed a novel physiological approach, which could avoid artifacts occurred in most existing algorithms. Inspired by the property of the human visual system (HVS), this dynamic range expansion scheme performs with a low computational complexity and a limited number of parameters and obtains high-quality HDR results. Comparisons with three recent algorithms in the literature also show that the proposed method reveals more important image details and produces …
Harnessing nature's insights: synthetic small molecules with peroxidase-mimicking DNAzyme properties.
2011
International audience
A Step into the Future: Applications of Nanoparticle Enzyme Mimics.
2018
We describe elementary concepts, up-to-date developments, and perspectives of the emerging field of nanoparticle enzyme mimics (so-called "nanozymes") at the interface of chemistry, biology, materials, and nanotechnology. The design and synthesis of functional enzyme mimics is a long-standing goal of biomimetic chemistry. Metal complexes, polymers and engineered biomolecules capturing the structure of natural enzymes or their active centers have been made to achieve high rates and enhanced selectivities. Still, the design of new "artificial enzymes" that are not related to proteins but with capacity of production and stability at industrial level, remains a goal. Inorganic nanoparticles bea…
Increased conformational rigidity of humic substances by oxidative biomimetic catalysis
2005
A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe(TDCPPS)Cl, was employed as a biomimetic catalyst in the oxidative coupling of terrestrial humic materials. High-performance size-exclusion chromatography (HPSEC), solid-state nuclear magnetic resonance (CPMAS-(13)C NMR), electron paramagnetic resonance (EPR), and diffuse reflectance infrared spectroscopy (DRIFT) were used to follow conformational and structural changes brought about in different humic materials by the oxidative coupling. Increase in apparent weight-average molecular weight (Mw(a)) occurred invariably for all humic substances with the oxidative polymerization catalyzed …
Biomimetic strategy towards gelatin coatings on PET. Effect of protocol on coating stability and cell-interactive properties
2019
Gelatin-modified poly(ethylene terephthalate) (PET) surfaces have been previously realized via an intermediate dopamine coating procedure that resulted in surfaces with superior haemocompatibility compared to unfunctionalized PET. The present study addresses the biocompatibility assessment of these coated PET surfaces. In this context, the stability of the gelatin coating upon exposure to physiological conditions and its cell-interactive properties were investigated. The proposed gelatin–dopamine-PET surfaces showed an increased protein coating stability up to 24 days and promoted the attachment and spreading of both endothelial cells (ECs) and smooth muscle cells (SMCs). In parallel, physi…
Visual learning in Drosophila: Application on a roving robot and comparisons
2011
Visual learning is an important aspect of fly life. Flies are able to extract visual cues from objects, like colors, vertical and horizontal distributedness, and others, that can be used for learning to associate a meaning to specific features (i.e. a reward or a punishment). Interesting biological experiments show trained stationary flying flies avoiding flying towards specific visual objects, appearing on the surrounding environment. Wild-type flies effectively learn to avoid those objects but this is not the case for the learning mutant rutabaga defective in the cyclic AMP dependent pathway for plasticity. A bio-inspired architecture has been proposed to model the fly behavior and experi…