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Poly- l-lactide acid (PLLA) scaffold has been modified to enhance its osteoconductive and osteoinductive properties in view of a bone tissue engineering application. Two approaches have been followed: (i) coating with laminin or fibronectin and (ii) grafting with arginine-glycine-aspatic acid (RGD) or SIKVAV peptides. Moreover we have added a bioactive molecule 1,25-(OH)2D3 into the scaffold that shows better cellular interaction to implement osteoinduction and osteogenesis. The two coatings promoted only cell adhesion in the very short term while even if grafted scaffolds had cell seeding efficiency similar to ungrafted PLLA, the grafted ones supported better the proliferation of seeded human osteoblast (hOB) and human mesenchymal stem cells (hMSCs) over 1 week of culture. Our data showed that in view of bone integration and bone regeneration, PLLA grafting with RGD can be considered a good substrate to induce hOB adhesion and proliferation but having no significant effect on the osteogenic induction, the scaffold has to be reinforced with osteoinductive molecules. It can be concluded from reverse transcriptase polymerase chain reaction results, alkaline phosphatase activity and mineralization assays that 1,25(OH)2D3 reinforced RGD-PLLA keeps increased cell proliferation supported by an upregulation of the studied osteogenic markers and induced hMSCs differentiation into osteoblasts demonstrating osteoinductivity and osteoconductivity of the new formulated scaffold. These results can lead to a future application of RGD-D3-PLLA as an osteogenic material for bone replacement. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3531-3539, 2014. [ABSTRACT FROM AUTHOR]

Combretastatin A-4 (CA-4), is a natural compound with a potent tubulin polymerization and cell growth inhibitor properties. For these reasons CA-4 is one of the most potent anti-vascular agents that shows strong cytotoxicity against a variety of human cancer cells, including multi-drug-resistant cancer cell lines. In order to complete the knowledge of metabolic fate of CA-4, the in vitro and in vivo phase II metabolism was investigated. Both in incubation with rat and human liver S9 preparation in the presence of 39-phosphoadenosine-5´-phosphosulfate (PAPS) as a cofactor the formation of a previously no reported sulphate metabolite was demonstrated through liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) data and comparison with a synthetic reference sample. In incubation of CA-4 using rat and human liver microsomes, the formation of CA-4 glucuronide was observed and chromatographic and mass spectral properties of the metabolite were achieved and compared with those of a synthetic reference sample. Incubation of CA-4 with rat and human liver S9 preparation in the presence of uridine-5´-diphosphoglucuronic acid trisodium salt (UDPGA) and an β-nicotinamide adenine dinucleotide phosphate, reduced form (NADPH)-regenerating system as cofactors resulted in the formation of glucuronides arising from phase I CA-4 metabolites. When CA-4 was administered intraperitoneally to rat at a dose of 30 mg kg-1, both glucuronide and sulphate metabolites were observed in LC-ESI-MS-MS chromatograms and their mass spectral data were identical to those obtained from synthetic standards. [ABSTRACT FROM AUTHOR]