Search results for "biophysic"
showing 10 items of 3565 documents
Microenvironments to study migration and somal translocation in cortical neurons
2018
Migrating post-mitotic neurons of the developing cerebral cortex undergo terminal somal translocation (ST) when they reach their final destination in the cortical plate. This process is crucial for proper cortical layering and its perturbation can lead to brain dysfunction. Here we present a reductionist biomaterials platform that faithfully supports and controls the distinct phases of terminal ST in vitro. We developed microenvironments with different adhesive molecules to support neuronal attachment, neurite extension, and migration in distinct manners. Efficient ST occurred when the leading process of migratory neurons crossed from low-to high-adhesive areas on a substrate, promoting spr…
The tumour microenvironment as an integrated framework to understand cancer biology
2019
Cancer cells all share the feature of being immersed in a complex environment with altered cell-cell/cell-extracellular element communication, physicochemical information, and tissue functions. The so-called tumour microenvironment (TME) is becoming recognised as a key factor in the genesis, progression and treatment of cancer lesions. Beyond genetic mutations, the existence of a malignant microenvironment forms the basis for a new perspective in cancer biology where connections at the system level are fundamental. From this standpoint, different aspects of tumour lesions such as morphology, aggressiveness, prognosis and treatment response can be considered under an integrated vision, givin…
Specific interaction of IM30/Vipp1 with cyanobacterial and chloroplast membranes results in membrane remodeling and eventually in membrane fusion.
2016
The photosynthetic light reaction takes place within the thylakoid membrane system in cyanobacteria and chloroplasts. Besides its global importance, the biogenesis, maintenance and dynamics of this membrane system are still a mystery. In the last two decades, strong evidence supported the idea that these processes involve IM30, the inner membrane-associated protein of 30kDa, a protein also known as the vesicle-inducing protein in plastids 1 (Vipp1). Even though we just only begin to understand the precise physiological function of this protein, it is clear that interaction of IM30 with membranes is crucial for biogenesis of thylakoid membranes. Here we summarize and discuss forces guiding I…
Imatinib-Loaded Micelles of Hyaluronic Acid Derivatives for Potential Treatment of Neovascular Ocular Diseases
2018
In this work, new micellar systems able to cross corneal barrier and to improve the permeation of imatinib free base were prepared and characterized. HA-EDA-C-16, HA-EDA-C-16-PEG, and HA-EDA-C-16-CRN micelles were synthesized starting from hyaluronic acid (HA), ethylenediamine (EDA), hexadecyl chains (C-16), polyethylene glycol (PEG), or L-carnitine (CRN). These nanocarriers showed optimal particle size and mucoadhesive properties. Imatinib-loaded micelles were able to interact with corneal barrier and to promote imatinib transcorneal permeation and penetration. In addition, a study was conducted to understand the in vitro imatinib inhibitory effect on a choroidal neovascularization process…
Toxic Tau Oligomers Modulated by Novel Curcumin Derivatives
2019
AbstractThe pathological aggregation and accumulation of tau, a microtubule-associated protein, is a common feature amongst more than 18 different neurodegenerative diseases that are collectively known as tauopathies. Recently, it has been demonstrated that the soluble and hydrophobic tau oligomers are highly toxic in vitro due to their capacity towards seeding tau misfolding, thereby propagating the tau pathology seen across different neurodegenerative diseases. Modulating the aggregation state of tau oligomers through the use of small molecules could be a useful therapeutic strategy to target their toxicity, regardless of other factors involved in their formation. In this study, we screen…
Microtubule disruption changes endothelial cell mechanics and adhesion
2019
AbstractThe interest in studying the mechanical and adhesive properties of cells has increased in recent years. The cytoskeleton is known to play a key role in cell mechanics. However, the role of the microtubules in shaping cell mechanics is not yet well understood. We have employed Atomic Force Microscopy (AFM) together with confocal fluorescence microscopy to determine the role of microtubules in cytomechanics of Human Umbilical Vein Endothelial Cells (HUVECs). Additionally, the time variation of the adhesion between tip and cell surface was studied. The disruption of microtubules by exposing the cells to two colchicine concentrations was monitored as a function of time. Already, after 3…
Bioelectrical Signals and Ion Channels in the Modeling of Multicellular Patterns and Cancer Biophysics
2016
AbstractBioelectrical signals and ion channels are central to spatial patterns in cell ensembles, a problem of fundamental interest in positional information and cancer processes. We propose a model for electrically connected cells based on simple biological concepts: i) the membrane potential of a single cell characterizes its electrical state; ii) the long-range electrical coupling of the multicellular ensemble is realized by a network of gap junction channels between neighboring cells; and iii) the spatial distribution of an external biochemical agent can modify the conductances of the ion channels in a cell membrane and the multicellular electrical state. We focus on electrical effects …
A novel 3D heterotypic spheroid model for studying extracellular vesicle-mediated tumour and immune cell communication
2017
Cancer-derived extracellular vesicles (EVs) have emerged as important mediators of tumour-host interactions, and they have been shown to exert various functional effects in immune cells. In most of the studies on human immune cells, EVs have been isolated from cancer cell culture medium or patients' body fluids and added to the immune cell cultures. In such a setting, the physiological relevance of the chosen EV concentration is unknown and the EV isolation method and the timing of EV administration may bias the results. In the current study we aimed to develop an experimental cell culture model to study EV-mediated effects in human T and B cells at conditions mimicking the tumour microenvi…
Resveratrol-Induced Temporal Variation in the Mechanical Properties of MCF-7 Breast Cancer Cells Investigated by Atomic Force Microscopy
2019
Atomic force microscopy (AFM) combined with fluorescence microscopy has been used to quantify cytomechanical modifications induced by resveratrol (at a fixed concentration of 50 µ
Polymeric hepatitis C virus non-structural protein 5A nanocapsules induce intrahepatic antigen-specific immune responses
2016
Targeting antigen combined with adjuvants to hepatic antigen-presenting cells (APCs) is essential for the induction of intrahepatic T cellular immunity controlling and resolving viral infections of the liver. Intravenous injection of antigen-loaded nanoparticles is a promising approach for the delivery of antigens to liver APCs. Accordingly, polymeric nanocapsules (NCs) synthesized exclusively of hepatitis C virus non-structural protein 5A (NS5A) and the adjuvant monophosphoryl lipid A (MPLA) adsorbed to the nanocapsule surface were developed. Aim of the present study was the evaluation of the in vitro and in vivo behavior of MPLA-functionalized NS5A-NCs regarding the interaction with liver…