Eclogite or jadeitite: The two colours involved in the transfer of alpine axeheads in western Europe

During the 5th and 4th millennia BC, the Neolithic extraction of stone around Mont Viso and in the Mont Beigua massif in the north Italian Alps resulted in the production of large polished axeheads in ecologite, omphacitite, jadeitite and amphibolite - raw materials which were not only rare but which also have remarkable mechanical and aesthetic properties. These axeheads circulated around western Europe over great distances and in particular, between the Alps, the Atlantic and the North Sea. Among these Alpine jades, research suggests a tendency for different raw materials to be represented in different geographic areas. Axeheads and other items made from dark-coloured rocks from the family of eclogites and omphacitites tend to predominate in the Paris Basin, in Germany and in Great Britain and Ireland. This paper documents the manufacture, circulation and deposition of different types of Alpine axeheads over time. More specifically, it discusses observed trends in relation to variability in the supply of raw materials and finished objects, the nature of regional traditions and long-distance transfer, and ultimately, the changing significance of axeheads as socially valorized artefacts

Human Tumour Immune Evasion via TGF-β Blocks NK Cell Activation but Not Survival Allowing Therapeutic Restoration of Anti-Tumour Activity

Immune evasion is now recognized as a key feature of cancer progression. In animal models, the activity of cytotoxic lymphocytes is suppressed in the tumour microenvironment by the immunosuppressive cytokine, Transforming Growth Factor (TGF)-β. Release from TGF-β-mediated inhibition restores anti-tumour immunity, suggesting a therapeutic strategy for human cancer. We demonstrate that human natural killer (NK) cells are inhibited in a TGF-β dependent manner following chronic contact-dependent interactions with tumour cells in vitro. In vivo, NK cell inhibition was localised to the human tumour microenvironment and primary ovarian tumours conferred TGF-β dependent inhibition upon autologous NK cells ex vivo. TGF-β antagonized the interleukin (IL)-15 induced proliferation and gene expression associated with NK cell activation, inhibiting the expression of both NK cell activation receptor molecules and components of the cytotoxic apparatus. Interleukin-15 also promotes NK cell survival and IL-15 excluded the pro-apoptotic transcription factor FOXO3 from the nucleus. However, this IL-15 mediated pathway was unaffected by TGF-β treatment, allowing NK cell survival. This suggested that NK cells in the tumour microenvironment might have their activity restored by TGF-β blockade and both anti-TGF-β antibodies and a small molecule inhibitor of TGF-β signalling restored the effector function of NK cells inhibited by autologous tumour cells. Thus, TGF-β blunts NK cell activation within the human tumour microenvironment but this evasion mechanism can be therapeutically targeted, boosting anti-tumour immunity

Asymmetric O–H insertion reaction of carbenoids catalyzed by chiral bicyclo bisoxazoline copper(I) and (II) complexes

International audienceChiral copper(I) and (II)-bicyclobisoxazoline complexes were found to catalyze the insertion of α-diazocarbonyl compounds into O–H bonds of alcohols. The insertion reactions of various α-diazopropionates proceeded with moderate yields (40–90%) and high enantioselectivities (up to 92% and 94% with copper(I) and copper(II)-catalysts, respectively). A predominant effect on the enantiocontrol of the reaction was observed when copper(I) and (II)-catalysts were associated with NaBARF and molecular sieves (4 Å). © 2016 Elsevier Lt

Design and electropolymerization of a new optically active iron tetraspirobifluorenyl porphyrin

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