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Waller, H.

Publications and source records attributed to Waller, H..

2 recordsLinked to original sources

Comparison of concentrations of lead (Pb) in meat from wild-shot common pheasants killed using shotgun pellets principally composed of lead, iron (Fe), bismuth (Bi) and zinc (Zn)

The source of almost all of the lead (Pb) found in meat from carcasses of wild-shot small game animals is often thought to be small embedded fragments of the lead shotgun pellets usually used by hunters to kill them. Available circumstantial evidence supports this conjecture, but an unknown proportion of the lead in game meat might be biologically-incorporated and absorbed by the game animal from ingested shotgun pellets and other environmental sources, such as soil and residues from mining. A critical test comparing lead concentrations in meat from animals known to have been killed using different types of shotgun ammunition has not been performed until now. We compared lead concentrations in samples of edible meat from carcasses of 27 wild-shot common pheasants (Phasianus colchicus) from which only lead shotgun pellets were recovered post mortem with concentrations for 20 birds from which only iron pellets were recovered. Shotgun pellets were removed from the meat samples before analysis. The mean concentration of lead was about 30 times greater in the meat of pheasants shot with lead than those shot with iron and was similar to mean concentrations of lead reported previously from Europe-wide samples of meat from wild-shot small game animals, including pheasants, killed using unknown types of ammunition. These results support the hypothesis that changing the type of shotgun ammunition in use for hunting from lead to iron would greatly reduce the concentration of lead in meat from wild-shot small game.

pharmacology and toxicology↗

Lasting alterations in monocyte and dendritic cell subsets in individuals after hospitalization for COVID-19

After more than two years the COVID-19 pandemic continues to burden healthcare systems and economies worldwide, and it is evident that long-term effects of the disease can persist for months post-recovery in some individuals. The activity of myeloid cells such as monocytes and dendritic cells (DC) is essential for correct mobilization of the innate and adaptive responses to a pathogen. Impaired levels and responses of monocytes and DC to SARS-CoV-2 is likely to be a driving force behind the immune dysregulation that characterizes severe COVID-19. Here, we followed, for 6-7 months, a cohort of COVID-19 patients hospitalized during the early waves of the pandemic. The levels and phenotypes of circulating monocyte and DC subsets were assessed to determine both the early and long-term effects of the SARS-CoV-2 infection. We found increased monocyte levels that persisted for 6-7 months, mostly attributed to elevated levels of classical monocytes. While most DC subsets recovered from an initial decrease, we found elevated levels of cDC2/cDC3 at the 6-7 month timepoint. Analysis of functional markers on monocytes and DC revealed sustained reduction in PD-L1 expression but increased CD86 expression across almost all cell types examined. Finally, viral load and CRP correlated to the appearance of circulating antibodies and levels of circulating DC and monocyte subsets, respectively. By elucidating some of the long-term effects that SARS-CoV-2 infection has on these key innate myeloid cells, we have shed more light on how the immune landscape remains affected in the months following severe COVID-19.

immunology↗