Root sprouting in Rumex acetosella under different nutrient levels

Growth of Rumex acetosella, a root sprouting plant, was studied in a pot experiment. Each plant of R. acetosella consisted of two ramets which were interconnected by a root about 9 cm long. One of the ramets was placed in a compartment with nutrient-rich soil, the other with nutrient-poor soil. The root connection between the ramets either remained intact or was severed at the nutrient interface after planting. Growth of new roots was prevented at the nutrient interface.The presence of a connection between the ramets did not affect biomass or shoot production in either soil compartment, indicating a poor integration of the interconnected plant systems. In the nutrient-rich environment, two to four times more shoots and biomass were produced than in the low nutrient regime. A large proportion of buds initiated on roots remained dormant, forming a bud bank. When the number of shoots or buds was expressed per g of root dry weight or per m of root length, the nutrient response was no longer evident or, in a few cases, a significant effect in the opposite direction was obtained. These results show that the greater production of buds and shoots in the nutrient-rich environment reflected an allometric relationship between root biomass and the number of buds and shoots initiated on the roots.     

Pyrrolizidine alkaloids from Anchusa strigosa and their antifeedant activity

The pyrrolizidine alkaloid (PA) content of flowers, leaves, and roots of Anchusa strigosa (Boraginaceae) was analysed by ESI-LC-MS. Six PAs, including two new natural compounds, were detected, characterized by NMR spectroscopy, and quantified in each plant organ. The results indicated that the highest total concentration of PAs was in the leaves (23.63 mg/g of dried part), followed by the flowers (19.77 mg/g), and finally by the roots (1.80 mg/g). All PAs isolated were subjected to Spodoptera exigua and Pieris brassicae larvae. Feeding activity by both herbivore species using a bioassay was inhibited up to circa 75% depending on PA and applied concentration.     

Peeling an onion: the “refugee crisis” from a historical perspective

This paper asks a simple question: why did Western and other European politicians become so alarmed and, in some cases, downright apocalyptic at the rise of asylum seekers in 2014–16, especially compared to the previous refugee crisis in the 1990s? This paper argues that in 2014/2015, a “perfect storm” developed, bringing together factors that in the past had been largely unrelated and then converged with new ones. Peeling the onion of societal discontent with migrants and refugees has revealed five necessary and sufficient conditions: (1) discomfort with immigration and integration of colonial and labour migrants from North Africa and Turkey (1970–80s); (2) growing social inequality and widespread pessimism about globalization (1980s–); (3) A growing discomfort with Islam (1990s–); (4) Islamist terrorism (2000s–) and (5) the rise of radical right populist parties (2000s).     

Short Communication: Analysis of effective light in different photobioreactors: its influence on growth,photosynthetic activity and glycerol production by the freshwater green alga Chlamydomonas reinhardtii

The unicellular green alga Chlamydomonas reinhardtii synthesizes glycerol as an osmoregulatory metabolite when exposed to high saline concentrations (200 mM NaCl). Response to osmotic stress can be used for biotechnological production of this compound. When synthesis of a substance is linked to photosynthetic capacity and consequently to effective light, the production on a large scale makes an efficient utilization of light necessary. In the present work a model for evaluation of effective light has been tested.     

Metabolic stress boosts humoral responses in vivo independently of inflammasome and inflammatory reaction

Adjuvant formulations boost humoral responses by acting through several, yet incompletely elucidated pathways. In this study, we show that oligomycin or 5-aminoimidazole-4-carboxamide-1-β-D-ribonucleoside (AICAR) enhances Ab production when coinjected with T cell-dependent Ags. Oligomycin and AICAR lead to intracellular ATP reduction, suggesting that metabolic stress could be sensed by immune cells and leads to increased humoral responses. AICAR promotes IL-4 and IL-21 by naive Th cells but does not affect dendritic cell activation/maturation in vitro or in vivo. Accordingly, the adjuvant effect of AICAR or oligomycin does not require MyD88 or caspase-1 expression in vivo. Because AICAR is well tolerated in humans, this compound could represent a novel and safe adjuvant promoting humoral responses in vivo with a minimal reactogenicity.     

Anti-tumor necrosis factor treatment in occult hepatitis B virus infection: a retrospective analysis of 62 patients with psoriatic disease

One of the problems possibly related to the use of biological agents targeting tumor necrosis factor (TNF)-alpha is the increased risk of infections, including the activation of hepatitis B virus (HBV). HBV activation can occur in carriers of hepatitis B surface antigen (HBsAg), but the risk may also involve the HBsAg-negative (anti-HBc ± anti-HBs) occult carriers. Precise data on the safety of anti-TNF and/or other immunosuppressive drugs in HBV occult carriers are not available. We performed a retrospective analysis of 62 psoriatic patients with occult HBV infection treated with anti-TNF biological agents over a period of approximately 4 years: 44 subjects were treated with etanercept, 8 with infliximab and 10 with adalimumab. During the observational treatment period, no signs of HBV activation were observed. Only in one patient the reappearance of HBsAg, without detectable HBV-DNA, was noted before retreatment with etanercept and after 10 months from discontinuation of the previous course. In this patient etanercept was re-administered in association with lamivudine without any adverse event. Our results suggest the overall safety of treatment with anti-TNF drugs in HBV occult carriers, although a careful and constant monitoring of virological markers is required in such patients during treatment with anti-TNF drugs in order to have an early recognition of viral reactivation.     

New encounters in Arctic waters: a comparison of metabolism and performance of polar cod (<Emphasis Type="Italic">Boreogadus saida</Emphasis>) and Atlantic cod (<Emphasis Type="Italic">Gadus morhua</Emphasis>) under ocean acidification and warming

Oceans are experiencing increasing acidification in parallel to a distinct warming trend in consequence of ongoing climate change. Rising seawater temperatures are mediating a northward shift in distribution of Atlantic cod (Gadus morhua), into the habitat of polar cod (Boreogadus saida), that is associated with retreating cold water masses. This study investigates the competitive strength of the co-occurring gadoids under ocean acidification and warming (OAW) scenarios. Therefore, we incubated specimens of both species in individual tanks for 4 months, under different control and projected temperatures (polar cod: 0, 3, 6, 8 °C, Atlantic cod: 3, 8, 12, 16 °C) and PCO₂ conditions (390 and 1170 µatm) and monitored growth, feed consumption and standard metabolic rate. Our results revealed distinct temperature effects on both species. While hypercapnia by itself had no effect, combined drivers caused nonsignificant trends. The feed conversion efficiency of normocapnic polar cod was highest at 0 °C, while optimum growth performance was attained at 6 °C; the long-term upper thermal tolerance limit was reached at 8 °C. OAW caused only slight impairments in growth performance. Under normocapnic conditions, Atlantic cod consumed progressively increasing amounts of feed than individuals under hypercapnia despite maintaining similar growth rates during warming. The low feed conversion efficiency at 3 °C may relate to the lower thermal limit of Atlantic cod. In conclusion, Atlantic cod displayed increased performance in the warming Arctic such that the competitive strength of polar cod is expected to decrease under future OAW conditions.