Publications by authors named "Chris Johnston"

Pexa, BS, Johnston, CD, Elder, EE, Ford, KR, Patterson, MQ, and Myers, JB. Pool-based surfboard elicits activation of posterior shoulder muscles during a surfing stroke. J Strength Cond Res 38(7): 1300-1304, 2024-Surfboard paddling may activate posterior shoulder muscles, which are critical to baseball pitchers' injury risk and performance.

View Article and Find Full Text PDF

Background: Following the introduction of an algorithm aiming to maximise life-years gained from liver transplantation in the UK (the transplant benefit score [TBS]), donor livers were redirected from younger to older patients, mortality rate equalised across the age range and short-term waiting list mortality reduced. Understanding age-related prioritisation has been challenging, especially for younger patients and clinicians allocating non-TBS-directed livers. We aimed to assess age-related prioritisation within the TBS algorithm by modelling liver transplantation prioritisation based on data from a UK transplant unit and comparing these data with other regions.

View Article and Find Full Text PDF

The management of anaerobic digestate is important to realize the value of the waste and enhance the whole system sustainability of anaerobic digestion. In this study, the phosphorus treatment of dirty irrigation water by biochar samples derived from digestate of anaerobic digestion were investigated. The biochars were further activated by steam activation with different duration time and KOH activation with different introducing ratios; the textural properties of biochars were optimized after activation from the aspect of biochar characterization.

View Article and Find Full Text PDF

Environmental and economic issues resulting from the unsustainable management of sewage sludge from wastewater have necessitated the development of eco-friendly sewage sludge disposal methods, whereas stormwater effluent contains tremendous amounts of pollutants. This study compares the feasibility and environmental impacts associated with incorporating biofilters with sludge-based activated carbon (SBAC) versus commercial activated carbon (CAC) for stormwater treatment. The results demonstrate that the construction and disposal life-cycle stages are the dominant contributors to several environmental impact categories, including resource scarcity, carcinogenic toxicity, terrestrial ecotoxicity, and ozone formation indicators.

View Article and Find Full Text PDF

In animal models of inflammatory colitis, pathology can be ameliorated by several intestinal helminth parasites, including the mouse nematode . To identify parasite products that may exert anti-inflammatory effects , we tested excretory-secretory (HES) products, as well as a recombinantly expressed parasite protein, transforming growth factor mimic (TGM), that functionally mimics the mammalian immunomodulatory cytokine TGF-β. HES and TGM showed a degree of protection in dextran sodium sulphate-induced colitis, with a reduction in inflammatory cytokines, but did not fully block the development of pathology.

View Article and Find Full Text PDF

Dental education has been delivered in Queen's University for just over 100 years, with the Dental School celebrating its centenary in 2020. During that time, the undergraduate curriculum has evolved greatly, through innovations in the delivery of teaching and assessment driven by changes in educational practice, developing technologies and, most recently, the COVID-19 pandemic. Throughout all of these changes, our focus remains on our students, their wellbeing, and their development as lifelong learners for a career in the dental profession.

View Article and Find Full Text PDF
Article Synopsis
  • Animal manure is a source of important nutrients but loses nitrogen as ammonia during storage, impacting health and the environment.
  • In an experiment, biochars made from miscanthus and anaerobic digestate, as well as lightweight expanded clay (LECA), were tested to see if they could reduce ammonia emissions during four months of manure storage.
  • Acid-activated biochars significantly decreased ammonia emissions by 37-51% in the first month and 25-28% over the entire storage period, while LECA reduced emissions by 21%, indicating that activated biochars are more effective at mitigating emissions compared to LECA.
View Article and Find Full Text PDF

Normothermic Regional Perfusion (NRP) has shown encouraging clinical results. However, translation from an experimental to routine procedure poses several challenges. Herein we describe a model that led to the implementation of NRP into standard clinical practice in our centre following an iterative process of refinement incorporating training, staffing and operative techniques.

View Article and Find Full Text PDF

Small-scale gasification Combined Heat and Power systems, fed by biowaste resources, have the potential to enhance local renewable energy production, reduce carbon emissions and address the challenges of waste disposal. However, there is a lack of understanding on the influence of challenging feedstocks, such as, for example, digestate, poultry litter and municipal solid waste, on the syngas quality and the incidence of the drying stage in the overall process. This paper addresses this gap by analysing and comparing 40 samples of the most common biowaste feedstocks.

View Article and Find Full Text PDF

Objective: Explore the impact of COVID-19 on patients on the waiting list for liver transplantation (LT) and on their post-LT course.

Design: Data from consecutive adult LT candidates with COVID-19 were collected across Europe in a dedicated registry and were analysed.

Results: From 21 February to 20 November 2020, 136 adult cases with laboratory-confirmed SARS-CoV-2 infection from 33 centres in 11 European countries were collected, with 113 having COVID-19.

View Article and Find Full Text PDF

Helminth parasites are effective in biasing Th2 immunity and inducing regulatory pathways that minimize excessive inflammation within their hosts, thus allowing chronic infection to occur whilst also suppressing bystander atopic or autoimmune diseases. Multiple sclerosis (MS) is a severe autoimmune disease characterized by inflammatory lesions within the central nervous system; there are very limited therapeutic options for the progressive forms of the disease and none are curative. Here, we used the experimental autoimmune encephalomyelitis (EAE) model to examine if the intestinal helminth and its excretory/secretory products (HES) are able to suppress inflammatory disease.

View Article and Find Full Text PDF

Anterior cruciate ligament reconstruction (ACLR) incurs a high risk of posttraumatic knee osteoarthritis (PTOA). Aberrant gait biomechanics contribute to PTOA and are attributable in part to quadriceps dysfunction. Vibration improves quadriceps function following ACLR, but its effects on gait biomechanics are unknown.

View Article and Find Full Text PDF

Allocation policies are necessary to ensure a fair distribution of a scarce resource. The goal of any liver transplant allocation policy is to achieve the best possible outcomes for the waiting list population, irrespective of the indication for transplant, whilst maximizing organ utilization. Organ allocation for liver transplantation has evolved from simple centre-based approaches driven by local issues, to complex, evidence-based algorithm prioritizing according to need.

View Article and Find Full Text PDF

Osteoarthritis is common following anterior cruciate ligament reconstruction (ALCR), and aberrant gait biomechanics are considered a primary contributor. Somatosensory dysfunction potentially alters gait biomechanics, but this association is unclear. Therefore, the purposes of this investigation were to compare somatosensory function between limbs and evaluate associations between somatosensory function and gait biomechanics linked to osteoarthritis development in individuals with ALCR.

View Article and Find Full Text PDF
Article Synopsis
  • Individuals who underwent anterior cruciate ligament reconstruction (ACLR) show increased co-activation of the quadriceps and hamstrings during walking tasks, especially during the heelstrike phase.
  • Co-activation levels were higher in ACLR limbs compared to the non-injured limb and healthy controls, which is linked to altered gait biomechanics like reduced knee flexion and altered ground reaction forces.
  • The findings suggest that this excessive muscle co-activation may play a role in developing post-traumatic osteoarthritis by negatively affecting joint health over time.
View Article and Find Full Text PDF

Nutrients (P, N) in stormwater runoff are a major cause of eutrophication and algal blooms. A promising solution to this problem is to amend the rain garden growing medium (RGGM) with sewage sludge-based activated carbon (SBAC). To optimize the SBAC production process, different metals, pyrolysis conditions (temperature, heating time, carrier gas), and post-treatments were explored.

View Article and Find Full Text PDF

In the course of a structure based drug discovery program the known anticancer candidate marimastat was uncovered as a potent inhibitor of an enzyme in nematode cuticle biogenesis. It was shown to kill Caenorhabditis elegans, and the sheep parasites Haemonchus contortus and Teladorsagia circumcinta via an entirely novel nematode-specific pathway, specifically by inhibiting cuticle-remodelling enzymes that the parasites require for the developmentally essential moulting process. This discovery prompted an investigation of the compound's effect on Heligmosomoides polygyrus parasites in a mouse model of helminth infection.

View Article and Find Full Text PDF

Helminth parasites defy immune exclusion through sophisticated evasion mechanisms, including activation of host immunosuppressive regulatory T (Treg) cells. The mouse parasite Heligmosomoides polygyrus can expand the host Treg population by secreting products that activate TGF-β signalling, but the identity of the active molecule is unknown. Here we identify an H.

View Article and Find Full Text PDF

Background: Helminth parasites have been reported to have beneficial immunomodulatory effects in patients with allergic and autoimmune conditions and detrimental consequences in patients with tuberculosis and some viral infections. Their role in coinfection with respiratory viruses is not clear.

Objective: Here we investigated the effects of strictly enteric helminth infection with Heligmosomoides polygyrus on respiratory syncytial virus (RSV) infection in a mouse model.

View Article and Find Full Text PDF

The TGF-β superfamily is an ancient metazoan protein class which cuts across cell and tissue differentiation, developmental biology and immunology. Its many members are regulated at multiple levels from intricate control of gene transcription, post-translational processing and activation, and signaling through overlapping receptor structures and downstream intracellular messengers. We have been interested in TGF-β homologues firstly as key players in the induction of immunological tolerance, the topic so closely associated with Ray Owen.

View Article and Find Full Text PDF

Background: Ulnar Collateral Ligament (UCL) tears are common in baseball players. Alterations in rotator cuff strength are believed to be associated with injury to the shoulder and/or elbow in baseball players.

Hypothesis/purpose: Baseball players diagnosed with a UCL tear will demonstrate decreased internal (IR) and external rotation (ER) force as an indication of isometric muscular strength in the throwing arm compared to IR and ER force of the throwing arm in healthy baseball players.

View Article and Find Full Text PDF

Background: Helminths infect more than a quarter of the world's population. Their success as parasites is the result of active immunomodulation of the host immune response, which can have benefits for the host, particularly in suppressing harmful allergic and autoimmune responses. Accordingly, we tested the hypothesis that helminth infection reduces the immune response to allograft transplantation.

View Article and Find Full Text PDF