Continuous compensation for cerebral dopamine deficiency represents an ideal treatment for Parkinson's disease. Dopamine does not cross the digestive and blood-brain barriers and is rapidly oxidized. The new concept is the intracerebroventricular administration of anaerobic dopamine (A-dopamine) using an abdominal pump connected to a subcutaneous catheter implanted in the third ventricle, near the striatum.
View Article and Find Full Text PDFBackground: Continuous compensation of dopamine represents an ideal symptomatic treatment for Parkinson's disease (PD). The feasibility in intracerebroventricular administration (i.c.
View Article and Find Full Text PDFBackground: Engineered nanomaterials may release nanosized residues, by degradation, throughout their life cycle. These residues may be a threat for living organisms. They may be ingested by humans through food and water.
View Article and Find Full Text PDFIn this response, we discuss the major differences that clearly distinguish our results from those mentioned by Faust et al. In particular, the experiments have been conducted on nanoparticles of different nature, what mainly explains the observed discrepancies.
View Article and Find Full Text PDFBackground: Titanium dioxide (TiO2) nanoparticles (NPs) are widely used due to their specific properties, like UV filters in sunscreen. In that particular case TiO2 NPs are surface modified to avoid photocatalytic effects. These surface-treated nanoparticles (STNPs) spread in the environment and might release NPs as degradation residues.
View Article and Find Full Text PDFMesoporous silica nanoparticles (MSN) were functionalised by aminofluorescein (AMF) with diethylenetriaminepentaacetic acid spacer molecules which provide free carboxylic groups for binding cell-specific ligands such as folate. AMF allowed the exploration of cellular uptake by HeLa cells using confocal microscopy and flow cytometry. The functionalized nanoparticles (MSN-AMF) penetrated efficiently into HeLa cell cytoplasm through a clathrin dependent endocytosis mechanism.
View Article and Find Full Text PDFWe report on the observation that mesoporous silica nanoparticles (MSNs), after being endocytosed, interfere with the MTT test in HeLa cells and astrocytes by accelerating the exocytosis of formazan crystals. The stimulation of MTT formazan exocytosis is probably related to perturbation of intracellular vesicle trafficking by MSN uptake as revealed by experiments in presence of chloroquine and genistein. Similar effect has been previously observed with a number of chemicals, especially with neurotoxic beta amyloid peptides, but not with nanoparticles.
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