CD21 B cell populations are altered following subcutaneous scrapie inoculation in sheep

In order to gain a better understanding of the pathogenesis of scrapie in sheep an experimental model was developed to characterise immune system cells in the minutes following inoculation with scrapie-brain homogenate. Four 1-year-old susceptible (ARQ/ARQ) sheep were inoculated via the subcutaneous route at four different peripheral lymph node (LNs) drainage sites, at specific time points, prior to euthanasia of the sheep. The LNs were removed post-mortem at 30, 90, 180 and 300 min after inoculation. Flow cytometric triple-labelling was carried out on the LN cells and indicated that inoculation of scrapie-brain homogenate adjacent to a lymph node may delay or even inhibit the number of host CD21⁺ B cells expressed within the first 5 h. Immunohistochemistry was used to attempt detection of the abnormal form of prion protein (PrP^sc) in draining LNs adjacent to inoculation sites, with negative results at those time points.     

New phenolic esters from the resinous exudate of Haplopappus taeda

Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.     

Soil microbiome biomass,activity, composition and CO2 emissions in a long-term organic and conventional farming systems

The implementation of environmentally friendly agricultural policies has increased the need to compare agricultural aspects of conventional (CON) and organic farming (ORG) systems. The objective of the present work was to compare the effects of an organic and conventional long-term experiment on bacterial and fungal biomass and activity, as well as soil CO₂ emission and readily available nitrogen forms in a soil cultivated with Helianthus annuus L. The microbial biomass was more active and abundant in ORG as well as soil CO₂ emission. Despite being less abundant, fungi were more active than bacteria in both ORG and CON experiments. 16S rRNA gene sequencing showed that the ORG treatment had a significantly greater bacterial richness than CON. Cyanobacteria, Actinobacteria and Proteobacteria were the most abundant phyla contributing more than others to the differences between the two systems. Moreover, the soil ${\mathit{NH}}_4^{+}$ and ${\mathit{NO}}_2^{-}$ content was not significantly different between ORG and CON, while ${\mathit{NO}}_3^{-}$ was less in ORG. ORG sunflower yield was significantly less compared with CON. While much remains to be discovered about the effects of these agricultural practices on soil chemical properties and microbial diversity, our findings may contribute to this type of investigation.