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Archaeological narratives have traditionally associated the rise of social and political 'complexity' with the emergence of agricultural societies. However, this framework neglects the innovations of the huntergatherer populations occupying the Siberian taiga 8000 years ago, including the construction of some of the oldest-known fortified sites in the world. Here, the authors present results from the fortified site of Amnya in western Siberia, reporting new radiocarbon dates as the basis for a re-evaluation of the chronology and settlement organisation. Assessed within the context of the changing social and environmental landscape of the taiga, Amnya and similar fortified sites can be understood as one facet of a broader adaptive strategy. Keywords: Mesolithic, Neolithic, Eurasia, radiocarbon dating, palaeoenvironment, 8.2 ka event, fortification, Introduction The subarctic boreal landscapes of the Siberian taiga may seem remote, but it is here, 8000 years ago, that hunter-gatherers built fortified settlements, many centuries before comparable enclosures first [...]

The thermal inactivation of BoNT/A, BoNT/A complex, BoNT/B, and BoNT/B complex in cow's milk in a pasteurization process similar to the industry standard is described. The high-temperature short-time (HTST) pasteurization process in the dairy industry is found to remarkably reduce the risk of consumer harm even if larger amounts of BoNT were deliberately released into the milk supply chain.

Human tuberculosis (TB) is a leading global health threat and still constitutes a major medical challenge. However, mechanisms governing tissue pathology during post-primary TB remain elusive, partly because genetically or immunologically tractable animal models are lacking. In human TB, the demonstration of a large relative increase in interleukin (IL)-4 and IL-13 expression, which correlates with lung damage, indicates that a subversive T helper (TH)2 component in the response to Mycobacterium tuberculosis (Mtb) may undermine protective immunity and contribute to reactivation and tissue pathology. Up to now, there has been no clear evidence regarding whether IL-4/IL-13-IL-4 receptor-α (Rα)-mediated mechanisms may in fact cause reactivation and pathology. Unfortunately, the virtual absence of centrally necrotizing granulomas in experimental murine TB is associated with a poor induction of a TH2 immune response. We therefore hypothesize that, in mice, an increased production of IL-13 may lead to a pathology similar to human post-primary TB. In our study, aerosol Mtb infection of IL-13-over-expressing mice in fact resulted in pulmonary centrally necrotizing granulomas with multinucleated giant cells, a hypoxic rim and a perinecrotic collagen capsule, with an adjacent zone of lipid-rich, acid-fast bacilli-containing foamy macrophages, thus strongly resembling the pathology in human post-primary TB. Granuloma necrosis (GN) in Mtb-infected IL-13-over-expressing mice was associated with the induction of arginase-1-expressing macrophages. Indirect blockade of the endogenous arginase inhibitor l-hydroxyarginine in Mtb-infected wild-type mice resulted in a strong arginase expression and precipitated a similar pathology of GN. Together, we here introduce an experimental TB model that displays many features of centrally necrotizing granulomas in human post-primary TB and demonstrate that IL-13/IL-4Rα-dependent mechanisms leading to arginase-1 expression are involved in TB-associated tissue pathology., (© 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.)