ABSTRACT. Penetratin is a widely used carrier peptide showing promising potential for mucosal delivery of therapeutic proteins. In the present study, the importance of specific penetratin residues and pH was investigated with respect to complexation with insulin and subsequent transepithelial insulin permeation. Besides penetratin, three analogues were studied. The carrier peptide-insulin complexes were characterized in terms of size and morphology at pH 5, 6.5, and 7.4 by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. At pH 7.4 mainly very large complexes were present, while much smaller complexes dominated at pH 5. Presence of arginine residues in the carrier peptide proved to be a prerequisite for complexation with insulin as well as for enhanced transepithelial insulin permeation in vitro. Rearrangement of tryptophan residues resulted in significantly increased insulin permeation as compared to that of the parent penetratin. In general, precomplexation with penetratin and its analogues at pH 5 gave rise to increased insulin permeation as compared to that observed at pH 7.4; this finding was further supported by a preliminary in vivo study using the parent penetratin.

K(ATP) channel openers do not interact with CGRP release or mast cell degranulation. Activation of these channels in the CNS is antinociceptive and therefore cannot explain the headache induced by K(ATP) channel openers. Thus, they are likely to induce headache by interaction with extracerebral K(ATP) channels, probably the SUR2B isoforms.

ObjectiveTo compare the Danish Emergency Process Triage (DEPT) with a quick clinical assessment (Eyeball triage) as predictors of short-term mortality in patients in the emergency department (ED).MethodsThe investigation was designed as a prospective cohort study conducted at North Zealand University Hospital. All patient visits to the ED from September 2013 to December 2013 except minor injuries were included. DEPT was performed by nurses. Eyeball triage was a quick non-systematic clinical assessment based on patient appearance performed by phlebotomists. Both triage methods categorised patients as green (not urgent), yellow, orange or red (most urgent). Primary analysis assessed the association between triage level and 30-day mortality for each triage method. Secondary analyses investigated the relation between triage level and 48-hour mortality as well as the agreement between DEPT and Eyeball triage.ResultsA total of 6383 patient visits were included. DEPT was performed for 6290 (98.5%) and Eyeball triage for 6382 (~100%) of the patient visits. Only patients with both triage assessments were included. The hazard ratio (HR) for 48-hour mortality for patients categorised as yellow was 0.9 (95% CI 0.4 to 1.9) for DEPT compared with 4.2 (95% CI 1.2 to 14.6) for Eyeball triage (green is reference). For orange the HR for DEPT was 2.2 (95% CI 1.1 to 4.4) and 17.1 (95% CI 5.1 to 57.1) for Eyeball triage. For red the HR was 30.9 (95% CI 12.3 to 77.4) for DEPT and 128.7 (95% CI 37.9 to 436.8) for Eyeball triage. For 30-day mortality the HR for patients categorised as yellow was 1.7 (95% CI 1.2 to 2.4) for DEPT and 2.4 (95% CI 1.6 to 3.5) for Eyeball triage. For orange the HR was 2.6 (95% CI 1.8 to 3.6) for DEPT and 7.6 (95% CI 5.1 to 11.2) for Eyeball triage, and for red the HR was 19.1 (95% CI 10.4 to 35.2) for DEPT and 27.1 (95% CI 16.9 to 43.5) for Eyeball triage. Agreement between the two systems was poor (kappa 0.05).ConclusionAgreement between formalised triage and clinical assessment is poor. A simple clinical assessment by phlebotomists is superior to a formalised triage system to predict short-term mortality in ED patients.

Glucose is the main energy substrate for neurons, and ketone bodies are known to be alternative substrates. However, the capacity of ketone bodies to support different neuronal functions is still unknown. Thus, a change in energy substrate from glucose alone to a combination of glucose and b-hydroxybutyrate might change neuronal function as there is a known coupling between metabolism and neurotransmission. The purpose of this study was to shed light on the effects of the ketone body b-hydroxybutyrate on glycolysis and neurotransmission in cultured murine glutamatergic neurons. Previous studies have shown an effect of b-hydroxybutyrate on glucose metabolism, and the present study further specified this by showing attenuation of glycolysis when b-hydroxybutyrate was present in these neurons. In addition, the NMDA receptor-induced calcium responses in the neurons were diminished in the presence of b-hydroxybutyrate, whereas a direct effect of the ketone body on transmitter release was absent. However, the presence of b-hydroxybutyrate augmented transmitter release induced by the K ATP channel blocker glibenclamide, thus giving an indirect indication of the involvement of K ATP channels in the effects of ketone bodies on transmitter release.