Cells bioactivity

Feelisch, M Brands, F, and Kelm, M. 1995. Human endothelial cells bioactivate organic nitrates to nitric oxide implications for the reinforcement of endothelial defense mechanisms. Eur J Clin Invest 25 17,1-1 AS. 

Superior cell bioactivity Feng et al. with higher levels of [117]... 

Stably immobilized 3D flat aggregates and exhibited superior cell bioactivity with higher levels of liver-specific function maintenance in terms of albumin secretion, urea synthesis and cytochrome P-450 enzyme than 3D spheroid aggregates formed on GC films. These results suggested that the GC-based nanofibrous scaffolds could be useful for various applications such as bioartificial liver-assist devices and tissue engineering for liver regeneration as primary hepatocytes culture substrates. 

In order to improve the targetability for specific cells, bioactive polymers can be encapsulated into liposomes, but it is necessary that the polymers do not have hydro-phobic moieties that can disturb the liposomal membrane [44,45]. Macrophageactivating polymers like poly(MAc-CDA) or poly(maleic acid-alt-vinyladenine) were encapsulated into liposomes [44-47]. By coating the liposomes with polysaccharide... 

Proteias are metabolized coatiauously by all living organisms, and are ia dyaamic equilibrium ia living cells (6,12). The role of amino acids ia proteia biosyathesis has beea described (2). Most of the amino acids absorbed through the digestioa of proteias are used to replace body proteias. The remaining portioa is metabolized iato various bioactive substances such as hormones and purine and pyrimidine nucleotides, (the precursors of DNA and RNA) or is consumed as an energy source (6,13). 

Two other pyrrolopyrimidine nucleoside antibiotics, mycalisines A and B (56,57), have been isolated from the sponge Mycale sp. (173). These bioactive marine metaboHtes inhibit cell division of starfish eggs. 

It appears that none of these process techniques is dominant, at least with the lactide/glycolide materials. Researchers have considerable choices available in regard to fabrication of microspheres from these polymers. The most commonly used procedures employ relatively mild conditions of pH and temperature and are usually quite compatible with the bioactive agents to be entrapped, including proteins and other macromolecules. Only in the case of live virus and living cell encapsulation have serious deactivation problems been encountered and those problems were due to solvents used in the process. 

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