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Human hepatocytes in three-dimensional culture on Innovative biopolymeric scaffolds as a useful system for in vitro toxicology tests
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HUMAN HEPATOCY
TES IN THREE-
DIMENSIONAL CULTURE ON INNOVATIVE
BIOPOLYMERIC SCAFFOLDS
AS AN USEFUL SYSTEM
FOR
IN VITRO
TOXICOLOGY TESTS
Stampella A. (a), Massimi M. (b), Barbetta A.
(c), Rizzitelli G. (c), Dentini M. (c), Conti
Devirgiliis L. (a)
(a) Department of Biology and Biotechnology Charles Darwin, Sapienza University of
Rome, Rome, Italy
(b) Department of Basic and Applied Biology, University of L’Aquila, L’Aquila, Italy
(c) Department of Chemistry, Sapienza University of Rome, Rome, Italy
Many innovative biomaterials have recently be developed as scaffolds to replace
physiological matrix components and their im
provement has led to significant advances in
culture techniques in terms of cell survival, quantitative expansion, maintenance of
differentiated phenotype and specific cell functions. A key point in achieving these goals
has been to maintain a three-dimensional culture and the typical cyto-architecture of the
tissue by improving the extracellular matrix geometry and by promoting cell-cell contacts
and reciprocal adhesions. These bio-artificial
systems represent a real hope as functional
substitutes for damaged organs and tissues and have provoked a great interest in the field of
regenerative medicine. Concerning hepatocyte cultures, since the liver is the main organ
involved in detoxification processes and in the defence of organisms against harmful
molecules, in addition to their biomedical applications, these systems can be utilized as
invaluable tool for toxicology tests for analyzing the effects on metabolism of new drugs,
or for screening potentially toxic substances. The aim of our research was to identify the
most suitable biomaterial for the technological applications with hepatocytes. Since the
possibility to improve the performance of thes
e systems depends strongly on the methods
used to create the scaffolds, here we analyzed
porous matrices made of gelatin or blends of
gelatin and glycosaminoglycans, obtained with different methods for the culture of the C3A
cell line, considered a
good model of human hepatocytes. Scaffolds were obtained using
either a concentrated emulsi
on-templating technique known as High Internal Phase
Emulsion (HIPE) or a gas foaming technique; the latter method uses an inert gas instead of
the internal liquid phase toluene, avoiding the use of organic solvent and allowing the
creation of scaffolds with la
rger pores and interconnections. Cell viability was analysed
using MTS and LDH assays; ultrastructural morphology and three-dimensional cell
organization into the scaffold were assessed by SEM; albumin and urea secretion, as the
main metabolic markers of hepatocyte functions, were monitored using, respectively, an
ELISA kit and a colorimetric assay. Finally
Cytochrome P450-3A4 activity was quantified
by a luminescent method. Values of activity of this important enzyme of the detoxification
system, obtained in the absence or in the pr
esence of specific inducing molecules, were
compared between the different culture conditions
Calorimetric data on salt induced conformational transition of ionic polysaccharides in aqueous solution
No full textComparative analysis of the behavior of gellan gum (S-60) and welan gum (S-130) in dilute aqueous solution
No full textOn the optical activity of pseudoisocyanine bound to sulfate polysaccharides in dilute aqueous solution
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Conformation-dependent interaction between ionic polysaccharides and counterions in dilute aqueous solution
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
On the Optical Activity of Pseudoisocianine Bound by Sulfated Polysaccharides in Dilute Aqueous Solution
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