Search results for "Microscopy"

Nanoscale Mapping of the Physical Surface Properties of Human Buccal Cells and Changes Induced by Saliva

2019

International audience; The mucosal pellicle, also called salivary pellicle, is a thin biological layer made of salivary and epithelial constituents, lining oral mucosae. It contributes to their protection against microbiological, chemical, or mechanical insults. Pellicle formation depends on the cells’ surface properties, and in turn the pellicle deeply modifies such properties. It has been reported that the expression of the transmembrane mucin MUC1 in oral epithelial cells improves the formation of the mucosal pellicle. Here, we describe an approach combining classical and functionalized tip atomic force microscopy and scanning microwave microscopy to characterize how MUC1 induces change…

Effects of Cytokines on the Expression of Cell Adhesion Molecules by Cultured Human Omental Mesothelial Cells

1995

Cultured mesothelial cells (HOMES) are very responsive to the proinflammatory cytokines, interleukin (IL)-1 and tumor necrosis factor-alpha (TNF-alpha). E-selectin, ICAM-1 and VCAM-1 are known to play an important role, because they are presented by diverse cell types, for example endothelial cells (ECs), and interact with co-responding ligands on white blood cell membranes. In this study, the expression of ICAM-1, VCAM-1, E-selectin as well as PECAM-1 on cultured HOMES was studied over 5, 24, 48 and 72 h exposure to IL-1 beta, interferon-gamma and TNF-alpha. In previous studies we have shown that IL-1 beta and TNF-alpha increase the expression of ICAM-1, E-selectin and VCAM-1 on the cytopl…

Electron microscopic demonstration of intracelluar promethazine accumulation sites by a precipitation technique: application to the cerebellar cortex…

1996

A method is described that allows electron microscopic identification of the phenothiazine neuroleptic promethazine after supravital intracardiac injection of high drug concentrations (greater than or equal to 3 %). The cerebellar cortex of the mouse was used for the investigation. This procedure is based on simultaneous fixation of drug and tissue by immersion in a paraformaldehyde-glutaraldehyde solution with the addition of phosphomolybdic acid. The electron microscopic investigation revealed that the drug could easily be identified as an electron-dense precipitate. Subpopulations of neurons exhibited a higher affinity for the drug than others, but no preference for any nerve cell type …

Design of enzyme-mediated controlled release systems based on silica mesoporous supports capped with ester-glycol groups

2012

[EN] An ethylene glycol-capped hybrid material for the controlled release of molecules in the presence of esterase enzyme has been prepared. The final organic-inorganic hybrid solid S1 was synthesized by a two-step procedure. In the first step, the pores of an inorganic MCM-41 support (in the form of nanoparticles) were loaded with [Ru(bipy) 3]Cl 2 complex, and then, in the second step, the pore outlets were functionalized with ester glycol moieties that acted as molecular caps. In the absence of an enzyme, release of the complex from aqueous suspensions of S1 at pH 8.0 is inhibited due to the steric hindrance imposed by the bulky ester glycol moieties. Upon addition of esterase enzyme, del…

Neuron-specific expression of neuroglobin in mammals.

2004

Neuroglobin, a vertebrate oxygen-binding protein, is expressed in many regions of the adult brain. We examined the cell type-specific expression of neuroglobin in neurons and astroglial cells in primary cultures of fetal hippocampal cells and sections of the adult mouse brain using neuroglobin-specific polyclonal antibodies and cell type-specific markers NeuN and GFAP to differentiate between neurons and glial cells. Neuroglobin is exclusively expressed in neurons, but not in astroglial cells. Accordingly, neuroglobin was detected in two neuroblastoma cell lines (N2a, SH-SY5Y) and the pheochromocytoma cell line PC-12, but not in glioblastoma cell lines (DKMG, GAMG) or other, non-neural cell…

Changes in tubulin protein expression accompany reorganization of microtubular arrays during cell shaping in barley leaves

1998

Barley (Hordeum vulgare L.) leaves grow from the base and thus exhibit a smooth developmental gradient. Developing mesophyll cells acquire their typical lobed shape synchronously along this gradient. Successive changes in the patterns of cortical microtubules are involved in the shaping process. The changes include formation and dispersal of band-like structures, the establishment of a random network and a dramatic loss of microtubules after completion of cell shaping. When the relative tubulin contents were determined in consecutive segments taken along the leaf, two tubulin maxima were found. They coincided with the establishment of the microtubular bands and the random network, respectiv…

Cellular basis of abnormal tissue hardening in lung fibrosis examined with atomic force microscopy

2010

Spot compliant neuronal networks by structure optimized micro-contact printing

2001

Neuronal cell growth in vitro can be controlled with micropatterned structures of extracellular matrix proteins such as laminin. This technique is a powerful tool for studying neuronal cell function in order to increase experimental reproducibility and to specifically design innovative experimental setups. In this paper the correlation between the structural dimensions of the ECM pattern and the shape of the resulting cellular network is analyzed. The aim of the present study was to position neuronal cell bodies as precisely as possible and to induce directed cell differentiation. PCC7-MzN cells were cultured on laminin patterns. The line width, node size and gap size in-between cell adhesi…

Cellular interactions ofCandida albicanswith human oral epithelial cells and enterocytes

2010

The human pathogenic fungus Candida albicans can cause systemic infections by invading epithelial barriers to gain access to the bloodstream. One of the main reservoirs of C. albicans is the gastrointestinal tract and systemic infections predominantly originate from this niche. In this study, we used scanning electron and fluorescence microscopy, adhesion, invasion and damage assays, fungal mutants and a set of fungal and host cell inhibitors to investigate the interactions of C. albicans with oral epithelial cells and enterocytes. Our data demonstrate that adhesion, invasion and damage by C. albicans depend not only on fungal morphology and activity, but also on the epithelial cell type an…

Axonal control of the adult neural stem cell niche.

2014

SummaryThe ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSCs) in the walls of the lateral ventricles of the adult brain. How the adult brain’s neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that acti…