Racial and ethnic disparities of sudden unexpected infant death in large US cities: a descriptive epidemiological study.

Background: Sudden unexpected infant death (SUID) accounts for ~ 3400 deaths per year in the USA, and minimal progress has been made in reducing SUID over the past two decades. SUID is the sudden death of an infant that has occurred as a result of accidental suffocation in a sleeping environment, SIDS (sudden infant death syndrome), or from an unknown cause of death. Nationally, non-Hispanic Black (NHB) infants have twice the risk of SUID compared to non-Hispanic White (NHW) infants.

Role of signalling molecules in behaviours mediated by the δ opioid receptor agonist SNC80.

Background And Purpose: GPCRs exist in multiple conformations that can engage distinct signalling mechanisms which in turn may lead to diverse behavioural outputs. In rodent models, activation of the δ opioid receptor (δ-receptor) has been shown to elicit antihyperalgesia, antidepressant-like effects and convulsions. We recently showed that these δ-receptor-mediated behaviours are differentially regulated by the GTPase-activating protein regulator of G protein signalling 4 (RGS4), which facilitates termination of G protein signalling.

The behavioral effects of a mixed efficacy antinociceptive peptide, VRP26, following chronic administration in mice.

Rationale: VRP26 displays mu opioid receptor agonist and delta opioid receptor antagonist activity in vitro, a pharmacological profile purported to produce reduced tolerance, dependence, and rewarding effects. We hypothesized that VRP26 would display reduced adverse effects after chronic administration as compared with the traditional opioid analgesic fentanyl.

Objective: The aim of this study is to explore the development of tolerance, dependence, and conditioned place preference of VRP26 as compared with the traditional opioid analgesic fentanyl.