The Role of ATP-Sensitive Inward Rectifier Potassium Channels In The Regulation of Reactive Oxygen Species In The Western Honey Bee, APIS Mellifera L.

Colonies of managed honey bees are annually being lost at an unsustainable rate, partly due to reduced immunocompetence that leads to acute viral outbreaks and mortality. To aid in restoring honey bee health despite the myriad of environmental stressors, this thesis focuses on identifying novel physiological pathways that can mitigate virus-mediated mortality through increased immune function. Previous work has demonstrated that a family of potassium ion channels, termed KATP channels, mediate the survival of honey bees during infection from a model virus, suggesting KATP channels may drive antiviral immunity. Interestingly, these channels have been linked to the regulation of reactive oxygen species (ROS), which are known to function as an immune system stimulator during virus infection. Thus, the overarching goal of this thesis study was to validate the linkage between KATP channels, ROS, and bee survivorship. Our findings in this thesis provide evidence that pinacidil, a KATP channel activator, is capable of dramatically reducing antioxidant levels in bees during chemically-induced ROS, suggesting KATP channels play a part in regulating levels of ROS. Further, mortality was significantly reduced in bees from colonies that had heavy mite infestations, which supports the notion that ROS is an intermediate molecule for immune health. While additional investigation is required to fully characterize the relationship between KATP channels, ROS, and antiviral immunity, this study has begun to fill significant gaps in knowledge pertaining to mechanisms honey bees use to regulate their antiviral immune response

Applying Proteomics to Study Crosstalk at the Cartilage-Subchondral Bone Interface in Osteoarthritis: current Status and Future Directions

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Potassium ion channels as a molecular target to reduce virus infection and mortality of honey bee colonies

Declines in managed honey bee populations are multifactorial but closely associated with reduced virus immunocompetence and thus, mechanisms to enhance immune function are likely to reduce viral infection rates and increase colony viability. However, gaps in knowledge regarding physiological mechanisms or ‘druggable’ target sites to enhance bee immunocompetence has prevented therapeutics development to reduce virus infection. Our data bridge this knowledge gap by identifying ATP-sensitive inward rectifier potassium ( KATP) channels as a pharmacologically tractable target for reducing virus-mediated mortality and viral replication in bees, as well as increasing an aspect of colony-level immunity. Bees infected with Israeli acute paralysis virus and provided KATP channel activators had similar mortality rates as uninfected bees. Furthermore, we show that generation of reactive oxygen species (ROS) and regulation of ROS concentrations through pharmacological activation of KATP channels can stimulate antiviral responses, highlighting a functional framework for physiological regulation of the bee immune system. Next, we tested the influence of pharmacological activation of KATP channels on infection of 6 viruses at the colony level in the field. Data strongly support that KATP channels are a field-relevant target site as colonies treated with pinacidil, a KATP channel activator, had reduced titers of seven bee-relevant viruses by up to 75-fold and reduced them to levels comparable to non-inoculated colonies. Together, these data indicate a functional linkage between KATP channels, ROS, and antiviral defense mechanisms in bees and define a toxicologically relevant pathway that can be used for novel therapeutics development to enhance bee health and colony sustainability in the field

Occupational therapy predischarge home visits for patients with a stroke (HOVIS): results of a feasibility randomized controlled trial

Objective: To assess the feasibility of conducting a randomized controlled trial of occupational therapy predischarge home visits for people after stroke. Design: Randomized controlled trial and cohort study. We randomized eligible patients for whom there was clinical uncertainty about the need to conduct a home visit to a randomized controlled trial; patients for whom a visit was judged ‘essential’ were enrolled into a cohort study. Setting: Stroke rehabilitation unit of teaching hospital. Participants: One hundred and twenty-six participants hospitalized following recent stroke. Interventions: Predischarge home visit or structured, hospital-based interview. Main outcome measures: The primary objective was to collect information on the feasibility of a randomized controlled trial, including eligibility, control intervention and outcome assessments. The primary outcome measure was the Nottingham Extended Activities of Daily Living Scale at one month after discharge from hospital. Secondary outcomes included mood, quality of life and costs at one week and one month following discharge. Results: Ninety-three people were allocated to the randomized controlled trial; 47 were randomized to intervention and 46 to control. Thirty-three were enrolled into the cohort study. More people were allocated to the randomized controlled trial as the study progressed. One hundred and thirteen people (90%) received the proposed intervention, although there was a need for stricter protocol adherence. Follow-up was good: at one month 114 (90%) were assessed. There were no significant differences between the groups in the randomized controlled trial for the primary outcome measure at one month. The average cost of a home visit was £208. Conclusion: A trial is feasible and warranted given the resource implications of predischarge occupational therapy home visits

The effect of experience, simulator-training and biometric feedback on manual ventilation technique

Objective To determine the frequency of provision and main providers (veterinary surgeons, nurses or trainees) of manual ventilation in UK veterinary practices. Furthermore, to determine the variation in peak inspiratory (inflation) pressure (PIP), applied to a lung model during manual ventilation, by three different groups of operators (inexperienced, experienced and specialist), before and after training. Study Design Questionnaire survey. Development of a lung model simulator with real-time biometric (manometry) feedback capability and its testing as a training tool on operators with a range of experiences. Methods Postal questionnaires were sent to 100 randomly selected veterinary practices. The lung model simulator was manually ventilated, in a staged process over three weeks, with and without real-time biometric feedback (PIP display), by three groups of volunteer operators: inexperienced, experienced and specialist. Results The questionnaires determined that veterinary nurses were responsible for providing the majority of manual ventilation in veterinary practices, mainly drawing on theoretical knowledge rather than any specific training. Thoracic surgery and apnoea were the main reasons for provision of manual ventilation. Specialists performed well when manually ventilating the lung model, regardless of feedback-training. Both inexperienced and experienced operators showed significant improvement in technique when using the feedback training tool: variation in PIP decreased significantly until subjects provided manual ventilation at peak inspiratory pressures within the defined optimum range. Preferences for different forms of feedback (graphical, numerical or scale display), revealed that the operators’ choice was not always the method which gave least variation in PIP. Conclusions and Clinical Relevance This study highlighted a need for training in manual ventilation at an early stage in veterinary and veterinary nursing careers and demonstrated how feedback is important in the process of experiential learning. A manometer device which can provide immediate feedback during training, or indeed in a real clinical setting, should improve patient safety

Clusterin secretion is attenuated by the proinflammatory cytokines interleukin‐1β and tumor necrosis factor‐α in models of cartilage degradation

The protein clusterin has been implicated in the molecular alterations that occur in articular cartilage during osteoarthritis (OA). Clusterin exists in two isoforms with opposing functions, and their roles in cartilage have not been explored. The secreted form of clusterin (sCLU) is a cytoprotective extracellular chaperone that prevents protein aggregation, enhances cell proliferation and promotes viability, whereas nuclear clusterin acts as a pro-death signal. Therefore, these two clusterin isoforms may be putative molecular markers of repair and catabolic responses in cartilage and the ratio between them may be important. In this study, we focused on sCLU and used established, pathophysiologically relevant, in vitro models to understand its role in cytokine-stimulated cartilage degradation. The secretome of equine cartilage explants, osteochondral biopsies and isolated unpassaged chondrocytes was analyzed by western blotting for released sCLU, cartilage oligomeric protein (COMP) and matrix metalloproteinases (MMP) 3 and 13, following treatment with the proinflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α. Release of sulfated glycosaminoglycans (sGAG) was determined using the dimethylmethylene blue assay. Clusterin messenger RNA (mRNA) expression was quantified by quantitative real-time polymerase chain reaction. MMP-3, MMP-13, COMP, and sGAG release from explants and osteochondral biopsies was elevated with cytokine treatment, confirming cartilage degradation in these models. sCLU release was attenuated with cytokine treatment in all models, potentially limiting its cytoprotective function. Clusterin mRNA expression was down-regulated 7-days post cytokine stimulation. These observations implicate sCLU in catabolic responses of chondrocytes, but further studies are required to evaluate its role in OA and its potential as an investigative biomarker

Physical separation techniques in water purification: an inquiry-based laboratory learning experience

This article outlines a structured investigative activity for students in lower secondary school. It was developed for the Australian Mathematics and Science Partnership Programme, a government initiative intended to promote the employment of more hands-on investigations in secondary science within Australian schools. The investigation focuses on water purification and is intended to develop conceptual knowledge of this topic and also high-level skills such as experimental design, particularly in relation to identifying and controlling variables. The investigation is outlined in detail and was trialed with practicing science teachers, school students and preservice secondary teachers. All of these groups provided feedback in various forms that indicated the investigation was valuable, relevant, interesting and allowed students to take some responsibility for their own inquiry learning

Synthesis, Characterisation and Application of Polymeric Scale Inhibitors

Desalination of seawater by both the evaporation (e.g. multi stage flash, MSF) and membrane (e.g. reverse osmosis, RO) processes encounters difficulties with precipitation of sparingly soluble inorganic salts such as calcium carbonate (CaCO), magnesium hydroxide (Mg(OH)) and calcium sulfate (CaSO). These precipitate during the desalination process when their solubility product Ksp is exceeded. To control this scaling problem, several methods for scale prevention and control are used, such as acid and additive treatments. Scale inhibitors are chemical additives that have gained importance in controlling scale formation and/or deposition in recent decades. These are low molecular weight organic compounds, typically phosphonates, or polymers of molecular weight 1000-4000, typically containing carboxylate, sulfonate or phosphonate groups