Social Transfer of Pathogenic Fungus Promotes Active Immunisation in Ant Colonies

Social contact with fungus-exposed ants leads to pathogen transfer to healthy nest-mates, causing low-level infections. These micro-infections promote pathogen-specific immune gene expression and protective immunization of nest-mates

Nitrate regulates floral induction in Arabidopsis, acting independently of light, gibberellin and autonomous pathways

The transition from vegetative growth to reproduction is a major developmental event in plants. To maximise reproductive success, its timing is determined by complex interactions between environmental cues like the photoperiod, temperature and nutrient availability and internal genetic programs. While the photoperiod- and temperature- and gibberellic acid-signalling pathways have been subjected to extensive analysis, little is known about how nutrients regulate floral induction. This is partly because nutrient supply also has large effects on vegetative growth, making it difficult to distinguish primary and secondary influences on flowering. A growth system using glutamine supplementation was established to allow nitrate to be varied without a large effect on amino acid and protein levels, or the rate of growth. Under nitrate-limiting conditions, flowering was more rapid in neutral (12/12) or short (8/16) day conditions in C24, Col-0 and Laer. Low nitrate still accelerated flowering in late-flowering mutants impaired in the photoperiod, temperature, gibberellic acid and autonomous flowering pathways, in the fca co-2 ga1-3 triple mutant and in the ft-7 soc1-1 double mutant, showing that nitrate acts downstream of other known floral induction pathways. Several other abiotic stresses did not trigger flowering in fca co-2 ga1-3, suggesting that nitrate is not acting via general stress pathways. Low nitrate did not further accelerate flowering in long days (16/8) or in 35S::CO lines, and did override the late-flowering phenotype of 35S::FLC lines. We conclude that low nitrate induces flowering via a novel signalling pathway that acts downstream of, but interacts with, the known floral induction pathways

Angiotensin receptor neprilysin inhibition versus individualized RAAS blockade: design and rationale of the PARALLAX trial

AIMS: Although the effect of the angiotensin receptor blocker neprilysin inhibitor (ARNI) sacubitril/valsartan on heart failure (HF) hospitalizations and cardiovascular death has been evaluated, its effects on functional capacity in patients with HF and ejection fraction (EF) >40% has yet to be determined. In addition, no prior studies have compared sacubitril/valsartan with angiotensin-converting enzyme inhibitor therapy. We sought to compare the effect of ARNI to background-medication-based individualized comparators (BMICs) on N-terminal pro-B-type natriuretic peptide (NT-proBNP), functional capacity [6 min walk distance (6MWD)], symptoms, and quality of life [Kansas City Cardiomyopathy Questionnaire (KCCQ)] in patients with HF and EF >40% in a randomized clinical trial. METHODS: PARALLAX is a prospective, randomized, controlled, double-blind multicentre clinical trial in patients with chronic symptomatic HF with EF >40%, New York Heart Association (NYHA) class II-IV symptoms, elevated natriuretic peptides, and evidence of structural heart disease. Eligible patients are randomized to sacubitril/valsartan vs. BMIC for cardiovascular and related co-morbidities. BMIC includes (i) enalapril, (ii) valsartan, and (iii) placebo depending on the type of medical therapy prior to enrolment. The primary endpoints are the change in plasma NT-proBNP concentration from baseline to 12 weeks and the change from baseline in 6MWD distance at 24 weeks. The secondary endpoints assess quality of life and symptom burden. CONCLUSIONS: PARALLAX will determine if sacubitril/valsartan compared with standard medical therapy for co-morbidities improves NT-proBNP levels, exercise capacity, quality of life, and symptom burden in HF patients with EF >40%