No abstract

Twenty-four healthy male volunteers received either placebo or 75, 150, or 300 microg filgrastim (recombinant methionyl human granulocyte colony-stimulating factor) for 12 days to study effects on monocytes and lymphocytes. In all filgrastim-treated groups, tumor necrosis factor alpha (TNF-alpha), interleukin-12 (IL-12), and interferon gamma (IFN-gamma) release by whole blood in response to endotoxin (lipopolysaccharide) was reduced. IL-12 added in vitro to lipopolysaccharide-stimulated blood of filgrastim-treated donors restored IFN-gamma and TNF-alpha release, suggesting that the anti-inflammatory effect of granulocyte colony-stimulating factor is exercised through IL-12 suppression. Phytohemagglutinin- or anti-CD3 antibody-induced lymphocyte proliferation ex vivo was reduced by 60% from day 5 to day 15, after a 50% increase at day 2 with concomitant doubled IL-2 release. In vivo, filgrastim induced doubling of all T-cell populations by day 8. Filgrastim decreased proinflammatory cytokine production and lymphocyte proliferation ex vivo throughout prolonged treatment at all doses. This indicates that endogenous granulocyte colony-stimulating factor may counterregulate the inflammatory cytokine cascade and implies a potential indication for filgrastim in chronic inflammatory conditions.

Nowadays, there is a strong interest in carbon nanotubes (CNTs) since these nanostructured materials have large potential applications in different technological fields. In this work, a very simple approach for synthesizing CNTs in mild conditions has been developed and investigated. In particular, the nanotubes have been obtained by thermal defluorination of poly(tetrafluoroethylene) (PTFE) by Si, which also acts as an inorganic catalyst for the CNT growth. Fine powders of PTFE and Si were homogeneously mixed together and then compacted by cold pressing. The obtained composite pills were placed into a quartz tube furnace at 650°C, and a vacuum was applied to remove the gaseous by‐product (SiF4). The obtained pyrolysis product consisted of CNTs, wrapping the surface of silicon grains. CNTs have been characterized by scanning electron microscopy, Raman spectroscopy, and large angle x‐ray powder diffraction. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 31: 246–251, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21267