Poly cell viability

Treatment with iron chelators and a-tocopherol protect against lipid p>eroxidation and hepatocellular injury in iron-overloaded rats (Sharma etal., 1990). When hepatocytes are isolated from rats, which have been pretreated with a-tocopherol, there is a significant reduction in iron-induced lipid peroxidation and improvement in cell viability in vitro (Poli et al., 1985). Similar effects were seen when hepatocytes were incubated with iron chelators (Bacon and Britton, 1990). Treatment of moderately, but not heavily, iron-loaded rats with desferrioxamine in vivo inhibits the pro-oxidant activity of hepatic ultrafiltrates (Britton et al., 1990b). 

Interferon induction in normal and leukemic lymphocyte cultures with tilorone has been observed50. The interferon response observed in normal lymphocyte cultures appeared to be correlated with the toxic effect of tilorone. The effect observed in leukemic cultures required higher concentrations of tilorone, but, similarly, appeared to be related to cell viability. Tilorone has been reported to stimulate production of interferon by itself in mouse embryo fibroblasts and, in combination with poly rl poly rC/DEAE-dextran in mouse L929 cells51. Human foreskin fibroblasts were not stimulated. The degree of synergism between tilorone and the nucleotide-dextran complex was proportional to the concentrations of tilorone and poly rl/poly rC and was influenced by the times of addition of the compounds relative to each other. 

Porous poly(DL-lactide) Cell viability was Rabbit chondrocytes Cells grown on PDLLA/chitosan PDLLA/chitosan Wu et al. 

A detailed study of the influence of nanocapsules with a multilayer shell on cell viability and cell penetration ability was very recently presented by Lukasiewicz and Szczepanowicz. Poly(L-lysine) polycations and poly(L-glutamic acid) polyanions were used to build the capsule walls and the PEG-ylated outer layer was introduced to render the system biocompatible. The authors showed the influence of the number of layers, surface charge, and the presence of outer PEG-ylated layer on the cytotoxicity of the formulation. An increase in a number of layers and positive surface charge led to a stronger negative effect on the cells, while PEG-ylation of the outer layer was beneficial. Interestingly, such PEG-modified nanocapsules were easily internalized by human embryonic kidney 293 (HEK 293) cells. 

Bone cell viability on methacrylic acid grafted and collagen immobilized porous poly(3-hydroxybutyrate-co-3-hydroxyvalerate). J. Appl. Polym. Sci., 98 (5), 1916-1921. 

At present, it is still difficult to definitely clarify the exact physiological significance of poly(ADP-ribose) synthetase in vivo. It is now clear, however, that the functions of this enzyme as determined in vitro can be divided into 3 categories as shown in Fig. 4. The first function is the reaction itself. Namely, the synthesis of poly(ADP-ribose) occurs with concomitant consumption of NAD. Whether or not poly(ADP-ribose) itself has any physiological function is still unknown. Nevertheless, the consumption of the substrate NAD will influence cell viability. 

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