Content validation of the HeartRunner questionnaire to volunteer responders dispatched to out-of-hospital cardiac arrests: A qualitative study.

Aim: To increase survival after out-of-hospital cardiac arrest (OHCA) in Denmark, volunteer responders are activated through a smartphone application (HeartRunner app) to quickly locate an automated external defibrillator (AED) and assist with cardiopulmonary resuscitation (CPR). All dispatched volunteer responders who have been activated by the app receive a follow-up questionnaire to evaluate their participation in the programme. The content of the questionnaire has never been thoroughly evaluated.

The PSY Peptide Family-Expression, Modification and Physiological Implications.

Small post-translationally modified peptides are gaining increasing attention as important signaling molecules in plant development. In the family of plant peptides containing tyrosine sulfation (PSYs), only PSY1 has been characterized at the mature level as an 18-amino-acid peptide, carrying one sulfated tyrosine, and involved in cell elongation. This review presents seven additional homologs in all sharing high conservation in the active peptide domain, and it shows that PSY peptides are found in all higher plants and mosses.

Evidence for multiple receptors mediating RALF-triggered Ca signaling and proton pump inhibition.

Acidification of the apoplastic space facilitates cell wall loosening and is therefore a key step in cell expansion. PSY1 is a growth-promoting secreted tyrosine-sulfated glycopeptide whose receptor directly phosphorylates and activates the plasma membrane H -ATPase, which results in acidification and initiates cellular expansion. Although the mechanism is not clear, the Rapid Alkalinization Factor (RALF) family of small, secreted peptides inhibits the plasma membrane H -ATPase, leading to alkalinization of the apoplastic space and reduced growth.

Activation of the LRR Receptor-Like Kinase PSY1R Requires Transphosphorylation of Residues in the Activation Loop.

PSY1R is a leucine-rich repeat (LRR) receptor-like kinase (RLK) previously shown to act as receptor for the plant peptide hormone PSY1 (peptide containing sulfated tyrosine 1) and to regulate cell expansion. PSY1R phosphorylates and thereby regulates the activity of plasma membrane-localized H-ATPases. While this mechanism has been studied in detail, little is known about how PSY1R itself is activated.

Receptor kinase-mediated control of primary active proton pumping at the plasma membrane.

Acidification of the cell wall space outside the plasma membrane is required for plant growth and is the result of proton extrusion by the plasma membrane-localized H+-ATPases. Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro and in planta with PSY1R, a receptor kinase of the plasma membrane that serves as a receptor for the peptide growth hormone PSY1. The intracellular protein kinase domain of PSY1R phosphorylates AHA2/AHA1 at Thr-881, situated in the autoinhibitory region I of the C-terminal domain.

Interaction of barley powdery mildew effector candidate CSEP0055 with the defence protein PR17c.

A large number of effector candidates have been identified recently in powdery mildew fungi. However, their roles and how they perform their functions remain unresolved. In this study, we made use of host-induced gene silencing and confirmed that the secreted barley powdery mildew effector candidate, CSEP0055, contributes to the aggressiveness of the fungus.