The fibers were characterized in terms of chemical composition, thermal stability (TGA), cristallinity (XRD) and surface morphology (SEM). The polymer thermal properties were evaluated by TGA and DSC. The composite characteristics were investigated by

mechanical tests (Izod impact strength, flexural resistance), thermal stability (TGA), water uptake and SEM micrographs of the fractured surfaces. The results showed that sisal and curaua fibers feature a huge potential as reinforcing agents of PBS due to their superior chemical compatibility with the aliphatic HSP activation matrix as well as to their surface morphology. Both factors contributed to the formation of a strong interface capable to effectively transfer the load from the matrix to the

fibers. Sisal/PBS and curaua/PBS composites also showed greater resistance against water absorption if compared to coconut/PBS and sugarcane bagasse/PBS see more composites. Novel biocomposites with good properties were produced from fibers and polymer that can obtained from renewable raw materials. (C) 2012 Elsevier B.V. All rights reserved.”
“Purpose

AMD3100, an antagonist of the CXCR4 chemokine receptor is soon to be used clinically for the peripheral mobilization of hematopoietic stem cells (HSCs) in patients with multiple myeloma. AMD3100 has been shown to activate a G protein coupled with CXCR4 and thus acts GSK2245840 in vitro as a partial CXCR4 agonist in vitro. Thus, we explored whether AMD3100 affected the survival and proliferation of myeloma cells in vitro.

Materials and Methods

The effects of AMD3100 on survival and proliferation of two myeloma cell lines (RPMI8226 and U266) as well as CD138+ cells obtained from several patients with multiple myeloma were analyzed by flow cytometry using annexin V and a colorimetric cell proliferation assay (CCK-8 assay).

Results

AMD3100, but not T140, another CXCR4 antagonist,

stimulated the proliferation of myeloma cell lines and CD138+ primary human myeloma cells (-2-fold increase) in a dose-dependent manner in serum-free culture for up to 5 days, which was inhibited by pretreating the cells with pertussis toxin. AMD3100 enhanced the proliferation of U266 cells induced by interleukin-6 and partially reversed AG490-mediated growth inhibition and apoptosis induced by serum deprivation in RPMI8226 cells. AMD3100 induced the phosphorylation of Akt and MAPK p44/p42 in U266 cells and MAPK p44/p42 in RPMI8226 cells. In contrast, AMD3100 markedly increased the cell apoptosis and reduced the number of RPMI8226 cells after 5 to 7 days of culture under serum-free conditions.

Conclusion

AMD3100 exerts dual effects, initially enhancing and subsequently inhibiting the survival and proliferation of myeloma cells, signaling via CXCR4 in vitro.