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Abstract: The surface of an implant device can be modified by immobilizing biological molecules on it to improve its integration into the host tissue. We have previously demonstrated that enzymatically tailored plant pectins are promising nanocoatings for biomaterials. This study investigates whether a coating of modified hairy region (rhamnogalacturonan-I) from apple pectin (MHR-α) which has anti-adhesive properties can inhibit the generation of inflammatory mediators by lipopolysaccharide (LPS)-activated macrophages. For that purpose, J774.2 murine macrophages were cultured for 24h on MHR-α-coated Petri dishes and tissue culture polystyrene controls, with and without LPS. Cell morphology, cell growth, nitrite and TNF-α secretion were studied. The results indicate that MHR-α coating inhibits the LPS-induced activation of macrophages. [Copyright &y& Elsevier]

Abstract: Recently, it has been shown that using a single-site catalytic system it is possible to tailor entanglement density in the amorphous region of a semi-crystalline polymer, such as polyethylene, with a molar mass greater than 1 million g/mol. The synthesized polymer can be processed in its solid-state, along uniaxial and biaxial directions. It also shows strong heating rate dependence on melting invoking kinetics in randomization of chains from crystal to amorphous phase. With the help of solid-state NMR the distinction between amorphous regions of the synthesized and commercially available ultra-high molar mass polyethylene is made. For example, the polymer synthesized under the controlled conditions, using a homogeneous single-site catalytic system, shows faster motion of methylene units from the noncrystalline to the crystalline regions compared to commercially available nascent polyethylene synthesized using a Ziegler–Natta (Z–N) catalyst. The differences in chain diffusion, and the resultant 13C polarization transfer from the noncrystalline to the crystalline region, are attributed to the difference in entanglement density arising from the polymerization method employed. The two polyethylene samples investigated are of similar molar mass and crystallinity. Conformational changes caused by deformation of the two samples have been characterized and co-relationship with the entanglement density has been established. [Copyright &y& Elsevier]