Tissue adhesives case studies

The receptor-like protein tyrosine phosphatases have a transmembrane and, in some cases, a large extracellular domain with a very variable structme (Fig. 8.16). Many, but not all, membrane protein tyrosine phosphatases have two catalytic domains in the cytoplasmic region. The complete structme is very similar to the structure of transmembrane receptors. Understanding of their function is far from complete. Both the natural ligands and the substrate proteins following in the sequence are incompletely characterized. Several studies have demonstrated a role for receptor-like PTPs in neuronal cell adhesion signaling pathways. In cells of the neural tissue, a surface protein, contactin has been identified as ligand for the extracellular domain of a protein tyrosine phosphatase (Peles et al., 1995). 

For Al Oj nanoparticles, most studies to date conclude that they are biocompatible and reveal little or no adverse effects. This conclusion has been verified in various tissue cells, zebrafish embryo, and frait flies [23,24]. For example, a recent dose-dependent study on human fibroblasts showed that Al Oj nanoparticles (at doses from 0.1 to 10mg/T75 flask) had no adverse effect on cell viability and DNA up to 5days [24]. However, there are a few cases that reported the opposite results. For example, Oesterling et al. [25] showed that the existence of AI2O3 nanoparticles increased the cytokine release and adhesion of activated monocytes, indicating proinflammatory responses induced by the nanoparticles. 

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