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The use of sulfur (S) in polluted soils can reduce metal(loid) toxicity and enhance phytoremediation effectiveness. Here we studied the response of barley plants to As in soil amended with sulfate or elemental sulfur throughout the growing cycle. A greenhouse experiment was carried out using 4-L pots filled with clay-loam soil spiked with 60 mg kg−1 As (Na2HAsO4·7H2O). Two chemical forms of sulfur (elemental sulfur (S0) or sulfate (CaSO4·2H2O)) were applied at a dose of 1 and 3 Mg ha−1, respectively, and two previously seeded barley plants were transplanted in each pot, using eight pots per treatment. At the end of the growing cycle, the biomass, nutrients, and metal(loid) content, as well as several physiological and biochemical parameters of the plants were analyzed. Moreover, the effect of the treatments on soil characteristics was also evaluated, including soil pore water. The treatment with sulfur promoted the growth of barley plants through their vegetative cycle, enhancing photosynthesis, although biomass did not significantly increase. Both sources of S promoted the accumulation of As in the root, thereby limiting its translocation to the aerial part of the plant, sulfate being more effective (an increase of 300%) than elemental S (an increase of 82%). The addition of S decreased soil pH. Furthermore, both treatments, but particularly sulfate, increased soluble sulfate and stimulated soil biological properties. In conclusion, the application of sulfate to As-polluted soil can enhance As phytostabilization by barley plants while simultaneously improving the biological properties of the soil.

The tumour necrosis factor superfamily OX40L and CD70 and their receptors are costimulatory signalling axes critical for adequate T and B cell activation in humans and mice. In this work we inoculated groups of sheep with human recombinant adenovirus type 5 (Ad) expressing Ovis aries (Oa)OX40L or OaCD70 or a control adenoviral vector to determine whether they could improve the immune response to the model antigen OVA. PBMCs and serum samples were obtained for analysis of the adaptive immune response to OVA at days 0, 15, 30 and 90 post-inoculation (pi). Recall responses to OVA were assessed at day 7 and 30 after the second antigen inoculation (pb) at day 90. Administration of these immunomodulatory molecules did not induce unspecific PBMC stimulation. While OaOX40L administration mainly increased TNF-α and IL-4 in PBMC at day 15 pi concomitantly with a slight increase in antibody titer and the number of IFN-γ producing cells, we detected greater effects on adaptive immunity after OaCD70 administration. AdOaCD70 inoculation improved antibody titers to OVA at days 30 and 90 pi, and increased anti-OVA-specific IgG-secreting B cell counts when compared to control. Moreover, higher IFN-γ production was detected on days 7 pi, 7 pb and 30 pb in PBMCs from this group. Phenotypic analysis of T cell activation showed an increase in effector CD8+ T cells (CD8+ CD62L- CD27-) at day 15 pi in AdOaCD70 group, concurrent with a decrease in early activated cells (CD8+ CD62L- CD27+). Moreover, recall anti-OVA CD8+ T cell responses were increased at 7 pb in the AdOaCD70 group. AdOaCD70 administration could therefore promote CD8+ T cell effector differentiation and long-term activity. In this work we characterized the in vivo adjuvant potential on the humoral and cellular immune response of OaOX40L and OaCD70 delivered by non-replicative adenovirus vectors using the model antigen OVA. We present data highlighting the potency of these molecules as veterinary vaccine adjuvant.

The global rise in population highlights the need for a greater production of quality food. In this regard, intensification of the agricultural sector and an increased use of fertilizers are key. Phosphorus (P), together with nitrogen (N) and potassium (K), is one of the essential elements for plant growth. Modern agriculture is dependent on P derived from phosphate rock, which is a non-renewable resource whose high-quality reserves are becoming increasingly scarce and expensive. In this context, alternative sources of P and the development of new recovery technologies are required. Such technologies are increasingly focused on struvite (MgNH4PO4·6H2O) (STR) from urban or livestock wastewater, whose accessibility is guaranteed. In this study, the medium–long term efficiency of STR from urban wastewater as a fertilizer was evaluated in three successive lettuce crops using a 25 kg pot trial. To this end, STR application was compared with the use of other conventional P fertilizers (NPK, monoammonium phosphate (MAP), and single superphosphate (SSP)) at a dose of 100 kg P ha−1. Crop biomass yield, P uptake, and the nutritional quality of the plants were determined. Moreover, the effect of STR on soil quality was examined using several soil biological indicators. In general, the STR treatment yielded similar biomass results to those obtained with NPK in the three successive lettuce crops. MAP and SSP treatments produced higher biomass in the first crop, but these values diminished in the next two. In relation to the effect on soil, STR treatment maintained the concentration of available P during the three growing cycles and enhanced microbial activity and functional diversity. On the basis of our findings, STR emerges as a sustainable P-fertilization strategy for lettuce production.