Publications by authors named "MacKenzie D"

The mucus layer covering the gastrointestinal (GI) epithelium is critical in selecting and maintaining homeostatic interactions with our gut bacteria. However, the underpinning mechanisms of these interactions are not understood. Here, we provide structural and functional insights into the canonical mucus-binding protein (MUB), a multi-repeat cell-surface adhesin found in Lactobacillus inhabitants of the GI tract.

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Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals.

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Background: Presentation of congenital megaureter in adult life is rare; patients usually become symptomatic in childhood.

Case Report: A 32-year-old man presented to the Emergency Department (ED) with dyspnea, tongue swelling, and a rash, which he attributed to amoxicillin he had taken shortly prior to onset of symptoms. He was hypotensive on arrival to the ED.

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The role of thyrotropin (thyroid-stimulating hormone, TSH) in driving peripheral thyroid function in non-mammalian species is still poorly understood. Thyroxine (T₄), the principal hormone released from the thyroid gland in response to TSH stimulation, circulates with a robust daily rhythm in the teleost fish the red drum. Previous research suggests that the red drum T₄ cycle is circadian in nature, driven by TSH secretion in the early photophase and inhibited by T₄ feedback in the early scotophase.

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Background And Objective: To describe a suction-based grasping tool for the surgical removal of irregular-shaped and nonferromagnetic intraocular foreign bodies.

Materials And Methods: A surgical tool with suction capabilities, consisting of a stainless steel shaft with a plastic handle and a customizable and interchangeable suction tip, was designed in order to better engage and manipulate irregular-shaped in-traocular foreign bodies of various sizes and physical properties. The maximal suction force and surgical capabilities were assessed in the laboratory and on a cadaveric eye vitrectomy model.

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Background: Healthcare-associated infections in long-term care facilities (LTCFs) are of increasing importance.

Aim: To develop consensus national performance indicators (NPIs) for infection control (ICPI) and antimicrobial stewardship (ASPI) in LTCFs, and assess the performance of 32 European countries against these NPIs.

Methods: Previously established European standards were the basis for consensus and the same iterative approach with national representatives from the 32 countries.

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Background: Visual observation is a key component of both formal and informal occupational performance assessment, but it is unknown how therapists gather this visual information.

Purpose: The purpose of this study was to explore observational behaviour of occupational therapists and non-health care professionals when watching videos of simulated clients post-stroke participating in everyday activity.

Method: Ten licensed occupational therapists and 10 age-, gender-, and education level-matched participants completed this eye-tracking study.

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Thyroid (TH) and growth (GH) hormones, and insulin-like growth factor I (IGF-I) are anabolic regulators in fish and responsive to nutrient intake. A study was conducted to determine if previously reported growth effects of dietary arginine (ARG) in channel catfish were related to the activation of endocrine axes. In a first experiment, catfish were fed incremental levels of ARG (0.

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The loss of functional Survival Motor Neuron (SMN) protein due to mutations or deletion in the SMN1 gene causes autosomal recessive neurodegenerative spinal muscle atrophy (SMA). A potential treatment strategy for SMA is to upregulate the amount of SMN protein originating from the highly homologous SMN2 gene, compensating in part for the absence of the functional SMN1 gene. We have previously shown that in vitro activation of the p38 pathway stabilizes and increases SMN mRNA levels leading to increased SMN protein levels.

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Background: The impact of neurological conditions on individuals, families and society is increasing and having a significant economic impact in Canada. While some economic data is known, the human costs of living with a neurological condition are poorly understood and rarely factored into future burden analyses. The "Living with the Impact of a Neurological Condition (LINC)" study aims to fill this gap.

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Background: Posterior shoulder dislocation is an uncommon disruption of the glenohumeral joint. Risk factors include seizure, electric shock, and underlying instabilities of the shoulder joint.

Case Report: A 27-year-old man with a history of recurrent posterior shoulder dislocation presented to the Emergency Department with sudden shoulder pain and reduced range of motion about the shoulder after abducting and internally rotating his arm.

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Fish are becoming an increasingly important research species as investigators seek alternatives to mammalian models. Combined positron emission tomography/computed tomography with ¹⁸F-fluorodeoxyglucose (FDG-PET/CT) is a powerful new technology that has been extensively applied for high-resolution imaging in mammals but not fish. CT scanning provides detailed anatomical three-dimensional imaging.

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Unlabelled: Spontaneous late subluxation of an intraocular lens (IOL) is a rare but serious complication of cataract surgery, often associated with poor zonular support. The management of this complication with a conventional forceps is difficult because the forceps often cannot adequately grasp the optic or haptic to fixate the IOL to the sclera or iris or remove it. The new suction-based grasping tool has a suction cup at the end.

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A tree surgeon presented to hospital with multiple blackening, non-blanching regions of skin on both forearms, following exposure to sap from the 'tree of heaven' (Ailanthus altissima). A referral to plastic surgery was made to consider debridement. Following input from the national poisons centre and dermatology, conservative management with emollient was undertaken.

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Many health professional education programs have instituted, or are in the process of developing, structures for implementing interprofessional education (IPE). Professional organizations are also adopting IP competencies for their respective memberships and accreditations. Our IPE design and educational framework was informed by evidence gathered from professional organizations; the students' lived experience with traditional approaches and evolving IPE designs and data from our school's longitudinal curriculum evaluation study.

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We present an integrated experimental and computational study of the molecular mechanisms by which myristoylation affects protein folding and function, which has been little characterized to date. Myristoylation, the covalent linkage of a hydrophobic C14 fatty acyl chain to the N-terminal glycine in a protein, is a common modification that plays a critical role in vital regulated cellular processes by undergoing reversible energetic and conformational switching. Coarse-grained folding simulations for the model pH-dependent actin- and membrane-binding protein hisactophilin reveal that nonnative hydrophobic interactions of the myristoyl with the protein as well as nonnative electrostatic interactions have a pronounced effect on folding rates and thermodynamic stability.

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Background: Splenic rupture or infarction can occur secondary to acute infectious mononucleosis. Patients with abdominal pain and known or suspected infectious mononucleosis mandate evaluation for these complications, which can have significant morbidity or mortality.

Case Report: An 18-year old man presented to the emergency department (ED) with a 2-day history of left upper quadrant abdominal pain.

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Thyrotropin (TSH) is a pituitary glycoprotein hormone heterodimer that binds to its G-protein coupled receptor (TSH-R) at the thyroid to promote the synthesis and secretion of thyroid hormone. Very little is known about TSH-TSH-R interactions in teleost fish. Mammalian gonadotropins have been reported to have an intrinsic ability to activate teleost fish TSH-Rs, suggesting the TSH-R in teleost fish is more promiscuous than in other vertebrates.

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Academia and small business research units are poised to play an increasing role in drug discovery, with drug repurposing as one of the major areas of activity. Here we summarize project status for a number of drugs or classes of drugs: raltegravir, cyclobenzaprine, benzbromarone, mometasone furoate, astemizole, R-naproxen, ketorolac, tolfenamic acid, phenothiazines, methylergonovine maleate and beta-adrenergic receptor drugs, respectively. Based on this multi-year, multi-project experience we discuss strengths and weaknesses of academic-based drug repurposing research.

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