Search results for "Adhesion"

Multifibrillar bundles of a self-assembling hyaluronic acid derivative obtained through a microfluidic technique for aortic smooth muscle cell orient…

2018

A hyaluronic acid derivative that is able to physically crosslink in a saline aqueous environment was employed for the production of fibers with a mean diameter of 50 μm using a microfluidic technique. The microfibers were collected in a tailored rotating collector and assembled to form multifibrillar bundles. The orientation of the microfibers on the collected bundles was evaluated by microCT analysis. The bundles were biofunctionalized by physical addition of fibronectin or chemical tethering of a cyRGDC peptide to achieve control of Aortic Smooth Muscle Cell (AoSMC) attachment, elongation and alignment. The mechanical performances of these bundles were evaluated by elongation tests, rela…

Synthetic Inhibitors of Cell Adhesion: A Glycopeptide from E-Selectin Ligand 1 (ESL-1) with the Arabino Sialyl Lewisx Structure

2001

Particularly selective methods are required for the synthesis of arabino sialyl Lewisx glycopeptides owing to the acid-labile β-arabinopyranoside bond. It is important for the inhibition of cell adhesion that the arabino sialyl Lewisx glycopeptide 1, which contains the Gly 672 -Asp 681 sequence of the E-selectin Ligand 1 (ESL-1), binds ten times more strongly than sialyl Lewisx to E-selectin, although it is monovalent and does not contain L-fucose, which is considered essential.

Role of genetic polymorphisms in myocardial infarction at young age

2010

Acute myocardial infarction (AMI) in young adult presents a typical pattern of risk factors, clinical, angiographic and prognostic characteristics. In the last years we demonstrated that hemorheological profile is altered in these patients in a persistent way and independently of the number of risk factors and of the extent of coronary lesions. Thus, the hyperviscosity syndrome following AMI could be considered an intrinsic characteristic of these patients. Consequently it is possible to hypothesise the presence of a genetic background at the origin of this predisposition. If this background is able to influence the risk of ischemic heart disease, this should be particularly evident in youn…

Effects of Parietaria judaica on human lung microvascular endothelial cells

2008

Cell adhesion on UV-crosslinked polyurethane gels with adjustable mechanical strength and thermoresponsiveness

2021

Temperature-responsive polyurethane (PU) hydrogels represent a versatile material platform for modern tissue engineering and biomedical applications. However, besides intrinsic advantages such as high mechanical strength and a hydrolysable backbone composition, plain PU materials are generally lacking bio-adhesive properties. To overcome this shortcoming, the authors focus on the synthesis of thermoresponsive PU hydrogels with variable mechanical and cell adhesive properties obtained from linear precursor PUs based on poly(ethylene glycol)s (pEG) with different molar masses, isophorone diisocyanate, and a dimerizable dimethylmaleimide (DMMI)-diol. The cloud point temperatures of the dilute,…

Mucoadhesive Polymer Hyaluronan as Biodegradable Cationic/Zwitterionic-Drug Delivery Vehicle

2014

Mucoadhesive polymers in pharmaceutical formulations release drugs in mucosal areas. They interact and fix to mucus via molecular interpenetration, etc ., which increase drug bioavailability. Polymers physicochemical properties affect formulation mucoadhesion, rheological behaviour and drug absorption. Hyaluronan (HA) is selected as a mucoadhesive and biodegradable polymer. Geometric, topological and fractal analyses are carried out with program TOPO. Reference calculations are performed with algorithm GEPOL. Procedure TOPO underestimates molecular volume by 0.7%. Error results 5% in surface area and derived topological indices. Solvent-accessible surface is undercalculated by 3%: from hexa…

Sponge aggregation factor: identification of the specific collagen-binding site by means of a monoclonal antibody.

1988

The aggregation factor (AF) from the sponge Geodia cydonium is known to be a complex proteinaceous particle, composed of a series of different (glyco)proteins (Mr lower than 150,000) around a 90S sunburst-like core structure. One of the low-Mr proteins is the 47-KD cell binding fragment. We describe a new monoclonal antibody (mAb), III1E6, raised against purified AF particles, which recognizes in tissue slices structures present both on the plasma membrane and in a network-like manner in the extracellular space. By applying immunoelectron microscopical, immunoblotting, and immunoaffinity chromatographical techniques, the mAb III1E6 was shown to recognize the core structure of the AF partic…

Cell adhesion molecule in the hexactinellid Aphrocallistes vastus

1984

Abstract The Hexactinellida sponge Aphrocallistes vastus contains a soluble aggregation factor (AF) whose purification has been described in this communication. It is characterized by a S° 20.w value of 37 and a buoyant density of 1.45 g/cm 3 . The AF is a glycoporteinaceous particle composed of three major protein species; no core structure could be visualized. In the presence of Ca 2+ , the AF causes secondary aggregation of single cells. The aggregation process is temperature, pH, and ionic strength independent within a broad range. Evidence is presented indicating that two (or more) AF molecules are required for the establishment of a stable cell: cell interaction. In contrast to the AF…

Absence of binding of human salivary glycoprotein to human gingival fibroblast-like cells in vitro.

1996

The aim of this study was to determine whether human high molecular weight salivary glycoprotein binds in vitro to human gingival fibroblast-like cells. Primary monolayer cultures of 2 human gingival fibroblast-like cell lines were incubated with a high molecular weight fraction of salivary glycoprotein which expressed blood group A activity and glycoprotein-cell binding probed using an FITC-conjugated mouse monoclonal antibody to human blood group A antigen. Surface fluorescence of protein-treated cells was found to be no greater than that of untreated or serum-treated control cultures. As significant binding of salivary glycoprotein to gingival fibroblast-like cells does not occur in vitr…

Adsorption-induced polymer translocation through a nanopore: a Monte Carlo investigation

2005

Abstract We study the translocation of a coarse-grained flexible polymer through a nanopore in a membrane induced by its adsorption on the trans side of the membrane. Dramatic differences in the threading behavior are observed if the adhesion to the membrane wall, e w , is below or above the adsorption threshold e c r . For e w e c r (weak adsorption) the activation barrier for translocation is at c cis 0 ≈ N / 2 (in terms of the fraction of chain c cis = N cis / N before the pore), independent of chain length N. For e w > e c r this barrier is at a constant (vanishing) number of passed trans monomers for all N. The mean time of chain passage τ trans ∝ c cis 1.3 when c cis c cis 0 . It scal…