Dysfunction of cell-cell tight junction (TJ) adhesions is a major feature in the pathogenesis of various diseases. Liver TJs preserve cellular polarity by delimiting functional bile-canalicular structures, forming the blood-biliary barrier. In acetaminophen-hepatotoxicity, the mechanism by which tissue cohesion and polarity are affected remains unclear. Here, we demonstrate that acetaminophen, even at low-dose, disrupts the integrity of TJ and cell-matrix adhesions, with indicators of cellular stress with liver injury in the human hepatic HepaRG cell line, and primary hepatocytes. In mouse liver, at human-equivalence (therapeutic) doses, dose-dependent loss of intercellular hepatic TJ-associated ZO-1 protein expression was evident with progressive clinical signs of liver injury. Temporal, dose-dependent and specific disruption of the TJ-associated ZO-1 and cytoskeletal-F-actin proteins, correlated with modulation of hepatic ultrastructure. Real-time impedance biosensing verified in vitro early, dose-dependent quantitative decreases in TJ and cell-substrate adhesions. Whereas treatment with NAPQI, the reactive metabolite of acetaminophen, or the PKCα-activator and TJ-disruptor phorbol-12-myristate-13-acetate, similarly reduced TJ integrity, which may implicate oxidative stress and the PKC pathway in TJ destabilization. These findings are relevant to the clinical presentation of acetaminophen-hepatotoxicity and may inform future mechanistic studies to identify specific molecular targets and pathways that may be altered in acetaminophen-induced hepatic depolarization.

Fully differentiated HepaRG™ cells are the hepatic cell line of choice for in vitro work in toxicology and drug trials. They are derived from a hepatoblast-like progenitor (HepaRG™-P) that differentiates into a co-culture of hepatocyte-like and cholangiocyte-like cells. This process that requires 2 weeks of proliferation followed by 2 weeks of differentiation using dimethylsulfoxide (DMSO) can be time consuming and costly. Identifying a method to accelerate HepaRG™-Ps towards a mature lineage would save both time and money. The ability to do this in the absence of DMSO would remove the possibility of confounding toxicology results caused by DMSO induction of CYP pathways. Impact statementWe show significantly earlier differentiation and function of HepaRG progenitor cells when grown in DMSO-free medium on oxygen plasma substrates vs standard tissue culture plastic. Further investigation showed that nanopatterning of oxygen plasma substrates did not confer any additional advantage over smooth oxygen plasma, though one pattern (DSQ120) showed comparable early differentiation and function.

Objectives & BackgroundAdolescents' opinions regarding health care is under-represented. The Royal Hospital for Sick Children Edinburgh is due to relocate to a new site in 2017 when it will also increase its age limit to <16 years (currently <13 yrs). This study investigates adolescents' opinions on the Emergency Department (ED) and determines what is important to them to ensure that we get it right.MethodsAn extensive literature search was performed which identified four key topics which formed the design of the questionnaire. Inclusion criteria were individuals aged between 12–16 years, presenting to the Royal Infirmary ED where adolescents are currently seen. The questionnaire was distributed to the ED for a month. Qualitative interviews were also conducted throughout the month using a template based on the questionnaire.ResultsIn total, 140 responses were received. The most important factor in an ED, according to adolescents was cleanliness (average importance rating of 4.69). The least important factor was entertainment which was given an importance rating of 2.46. However, when prompted to select one factor, being treated quickly was the most important (figure 1). Only 21% of respondents knew of the proposed move of the ED department, and overall this was deemed a positive idea (78%).Four main areas were considered when evaluating the results of our study. As age increased, the proportion of individuals preferring to be treated with adults increased. However, greater satisfaction was achieved when treated in child or adolescent-specific wards which suggests the use of age specific areas. Privacy was a concern expressed by adolescents potentially giving scope for improvement. The majority of respondents felt safe within an ED setting, however a small proportion did not. Our study suggested the feeling of safety is created by healthcare workers and familiarity with staff and the environment. Waiting times were consistently deemed important and reduced this would increase patient satisfaction.ConclusionLiterature specifically focusing on adolescents in this topic is limited. Our study attempts to fill in some of these gaps. Being seen quickly, cleanliness and clear explanations of treatments and procedures are the most important factors throughout the sample. The implications derived from our results suggest that the new ED adopt some changes including improving safety and waiting times to ensure we achieve high patient satisfaction.Figure 1