Search results for "in-vitro"
showing 10 items of 49 documents
Perylenetetracarboxylic anhydride as a precursor of fluorescent carbon nanoonion rings
2015
[EN] Thermal annealing at 400 degrees C of perylenetetracarboxylic anhydride in low molecular mass PEG gives rise to the formation of well defined nanoobjects of 2.5 nm height and size distribution from 10 to 65 nm (average 40 nm) after purification of the raw mixture with silicagel chromatography. TEM reveals that the flat nanoobjects are constituted of concentric graphenic rings (0.34 nm interlayer distance). The morphology of the nanoparticles resembles onion rings of nanometric dimensions (nanoonion rings C-NOR). C-NOR particles have an excitation dependent emission with lambda(em) from 430 to 570 nm and a maximum emission quantum yield of 0.49. C-NOR particles can be internalized into …
Carbon nanotube – Protamine hybrid: Evaluation of DNA cell penetration
2016
International audience; Carbon nanotubes (CNTs) represent a class of nanomaterials with important potential for biomedical and biotechnological applications. CNT based vectorization is an emerging approach to the transport of nucleic acid through cell membrane but limited by detachment of DNA and degradation process. To increase DNA internalization, it was proved that cationic functionalized CNT was essential. In such a way, protamine efficiently used in several transfection processes is a cationic protein which was never associated to CNT.We propose here a novel nanovector based on single-walled carbon nanotubes (SWCNT) functionalized by protamine. Our results based on qPCR methods clearly…
Differentiation of Murine C2C12 Myoblasts Strongly Reduces the Effects of Myostatin on Intracellular Signaling
2020
Alongside in vivo models, a simpler and more mechanistic approach is required to study the effects of myostatin on skeletal muscle because myostatin is an important negative regulator of muscle size. In this study, myostatin was administered to murine (C2C12) and human (CHQ) myoblasts and myotubes. Canonical and noncanonical signaling downstream to myostatin, related ligands, and their receptor were analyzed. The effects of tumorkines were analyzed after coculture of C2C12 and colon cancer-C26 cells. The effects of myostatin on canonical and noncanonical signaling were strongly reduced in C2C12 cells after differentiation. This may be explained by increased follistatin, an endogenous blocke…
Gellan gum-based delivery systems of therapeutic agents and cells.
2020
The purpose of this review is to make a summary of high quality research trends using gellan gum (GG) as a polymeric constituent for the design of innovative drug delivery systems and devices for biomedical applications, such as cell therapy and regenerative medicine. The use of gellan gum is described both in its native form and as chemically functionalized derivatives or physically mixed with natural or synthetic materials. Starting from a systematic study of recent research works, the main properties of the native polysaccharide have been highlighted and therefore some improvements have been focused thanks to the design of chemically functionalized derivatives and the use of composite ma…
Mumijo traditional medicine: fossil deposits from Antarctica (chemical composition and beneficial bioactivity)
2008
Mumijo is a widely used traditional medicine, especially in Russia, Altai Mountains, Mongolia, Iran Kasachstan and in Kirgistan. Mumijo preparations have been successfully used for the prevention and treatment of infectious diseases; they display immune-stimulating and antiallergic activity as well. In the present study, we investigate the chemical composition and the biomedical potential of a Mumijo(-related) product collected from the Antarctica. The yellow material originates from the snow petrels,Pagodroma nivea. Extensive purification and chemical analysis revealed that the fossil samples are a mixture of glycerol derivatives.In vitroexperiments showed that the Mumijo extract caused in…
The Concise Guide To Pharmacology 2021/22: G Protein-Coupled Receptors
2021
The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will s…
A Multivariate Analysis of HIV-1 Protease Inhibitors and Resistance Induced by Mutation
2005
This paper describes the use of the multivariate statistical procedure principal component analysis as a tool to explore the inhibitory activity of classes of protease inhibitors (PIs) against HIV-1 viruses (wild type and more-frequent single mutants, V82A, V82F, and I84V) and against protease enzymes. The analysis of correlations between biological activity and molecular descriptors or similarity indexes allowed a reliable classification of the 51 derivatives considered in this study. The best results were obtained in the case of the I84V mutant for which a high number of predictions was achieved. On this basis, this statistical approach is proposed as a reliable method for the prediction …
Ferrocenyl-Coupled N-Heterocyclic Carbene Complexes of Gold(I)
2016
Four gold(I) carbene complexes featuring 4-ferro-cenyl-substituted imidazol-2-ylidene ligands were investigated for antiproliferative and antivascular properties. They were active against a panel of seven cancer cell lines, including multidrug-resistant ones, with low micromolar or nanomolar IC50 (72 h) values, according to their lipophilicity and cellular uptake. The delocalized lipophilic cationic complexes 8 and 10 acted by increasing the reactive oxygen species in two ways: through a genuine ferrocene effect and by inhibiting the thioredoxin reductase. Both complexes gave rise to a reorganization of the F-actin cytoskeleton in endothelial and melanoma cells, associated with a G1 phase c…
The effect of chitosan on the bioaccessibility and intestinal permeability of acyclovir
2019
Chitosan is object of pharmaceutical research as a candidate permeability enhancer. However, chitosan was recently shown to reduce the oral bioavailability of acyclovir in humans. The effect of chitosan on two processes determining the oral bioavailability of acyclovir, bioaccessibility and intestinal absorption, was now investigated. Acyclovir's bioaccessibility was studied using the dynamic TNO gastro-Intestinal Model (TIM-1). Four epithelial models were used for permeability experiments: a Caco-2 cell model in absence and presence of mucus and both rat and porcine excised intestinal segments. Study concentrations of acyclovir (0.8 g/l) and chitosan (1.6 g/l and 4 g/l) were in line with t…
Characterization of Hydrophilic Gold(I) N-Heterocyclic Carbene (NHC) Complexes as Potent TrxR Inhibitors Using Biochemical and Mass Spectrometric App…
2017
We report here on the synthesis of a series of mono-and dinuclear gold(I) complexes exhibiting sulfonated bis(NHC) ligands and novel hydroxylated mono(NHC) Au(I) compounds, which were also examined for their 'biological activities. Initial cell viability assays show strong antiproliferative activities of the hydroxylated mono(NHC) gold compounds (8 > 9 > 10) against 2008 human ovarian cancer cells even after 1 h incubation. In order to gain insight into the mechanism of biological action of the gold compounds, their effect on the pivotal cellular target seleno-enzyme thioredoxin reductase (TrxR), involved in the maintenance of intracellular redox balance, was investigated in depth. Th…