Publications by authors named "Russell Fraser"

In the face of rising global demand and unsustainable production methods, cultivated crustacean meat (CCM) is proposed as an alternative means to produce delicious lobster, shrimp, and crab products. Cultivated meat requires starting stem cells that may vary in terms of potency and the propensity to proliferate or differentiate into myogenic (muscle-related) tissues. Recognizing that regenerating limbs are a non-lethal source of tissue and may harbor relevant stem cells, we selected those of the crayfish as our model.

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Cultivated crustacean meat (CCM) is a means to create highly valued shrimp, lobster, and crab products directly from stem cells, thus removing the need to farm or fish live animals. Conventional crustacean enterprises face increasing pressures in managing overfishing, pollution, and the warming climate, so CCM may provide a way to ensure sufficient supply as global demand for these products grows. To support the development of CCM, this review briefly details crustacean cell culture work to date, before addressing what is presently known about crustacean muscle development, particularly the molecular mechanisms involved, and how this might relate to recent work on cultivated meat production in vertebrate species.

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Teneurin C-terminal associated peptide (TCAP) is an ancient bioactive peptide that is highly conserved in metazoans. TCAP administration reduces cellular and behavioural stress in vertebrate and urochordate models, yet despite numerous studies in higher animals, there is limited knowledge of its role in invertebrates. In particular, there are no studies on TCAP's effects on the heart of any metazoan, which is a critical organ in the stress response.

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A 2-year-old, neutered male mixed-breed dog from Nova Scotia, Canada was evaluated for panuveitis, polyuria, polydipsia, and hind limb ataxia. Toxoplasmosis was diagnosed ante-mortem based on markedly increased titers. The post-mortem examination confirmed systemic toxoplasmosis and demonstrated disseminated protothecosis.

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Honey stimulates cellular secretion of cytokines, which has been attributed to activation of lipopolysaccharide (LPS)-dependent and LPS-independent pathways. The objective of this study was to identify whether LPS is present in Australian honey samples at levels that can stimulate interleukin-6 (IL-6) secretion by fibroblasts and whether it can transduce cell signalling by activating toll-like receptor 4 (TLR4). IL-6 was measured in culture media of fibroblasts exposed to honey for 24 h.

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Bioactivity-guided fractionation was used to isolate two compounds, tomentosenol A () and torellianone A (), from a cerumen extract from . The anti-fibrotic activity of these compounds was examined using human cultured neonatal foreskin fibroblasts (NFF) and immortalised keratinocytes (HaCaTs). Tomentosenol A (), inhibited NFF and HaCaT cell proliferation and prevented NFF and HaCaT scratch wound repopulation at 12.

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Background: Shedding of the endothelial glycocalyx (EG) is associated with poor outcomes in a range of conditions including sepsis. Fresh frozen plasma (FFP) restores the damaged EG to baseline thickness, however the mechanism for this effect is unknown, and some components of FFP have adverse effects unrelated to the EG. There is some limited evidence that sphingosine-1-phosphate (S1P) within FFP restores the EG by activating the endothelial cell S1P receptor 1 (S1PR).

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Background And Aim: Contrast-enhanced ultrasound (CEUS) measures of post-occlusion skeletal muscle microvascular responsiveness demonstrate the microvascular dysfunction associated with ageing and age-related disease. However, the accessibility of CEUS is limited by the need for intravenous administration of ultrasound contrast agents and sophisticated imaging analysis. Alternative methods are required for the broader assessment of microvascular dysfunction in research and clinical settings.

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Background: Continuous renal replacement therapy (CRRT) with regional citrate anticoagulation (RCA) is now commonly used to treat acute kidney injury in critically ill patients. The concentration of citrate is not routinely measured, with citrate accumulation and/or toxicity primarily assessed using surrogate measures.

Objectives: The aim of this study was to measure the concentration of citrate in plasma and ultrafiltrate in patients receiving CRRT with RCA using a modified commercial enzymatic assay.

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Abdominal aortic aneurysm (AAA) is a vascular disease involving permanent focal dilation of the abdominal aorta (≥30 mm) that can lead to catastrophic rupture. Destructive remodeling of aortic connective tissue in AAA contributes to wall stiffening, a mechanical parameter of the arterial system linked to a heightened risk of cardiovascular morbidity and mortality. Since aortic stiffening is associated with AAA progression, treatment options that target vascular inflammation would appear prudent.

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Antioxidant activity of honeys may be beneficial in wound healing processes by protecting cells against lipid oxidation. The DPPH assay assesses the efficacy of antioxidant molecules to reduce DPPH to DPPHH. Studies determining EC are limited by single time-point determinations of antioxidant effect and can miss vital information about the rate of antioxidant response.

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New Findings: What is the central question of the study? Cuff-occlusion duration may influence contrast-enhanced ultrasound (CEUS) assessments of skeletal muscle microvascular blood flow responsiveness: what are the effects of 1, 3 and 5 min cuff-occlusion on the magnitude and reliability of calf muscle microvascular blood flow responsiveness in older adults? What is the main finding and its importance? Calf muscle microvascular blood flow responsiveness was enhanced following 5 min cuff-occlusion compared with 1 min. The reliability of post-occlusion CEUS measurements was also improved following 5 min occlusion. The use of a standardized 5 min occlusion period should therefore be considered in future studies and clinical practice.

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Macrophages are implicated in the pathogenesis of abdominal aortic aneurysm (AAA). This study examined the environmentally conditioned responses of AAA macrophages to inflammatory stimuli. Plasma- and blood-derived monocytes were separated from the whole blood of patients with AAA (30-45 mm diameter; = 33) and sex-matched control participants ( = 44).

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Background: Salmonella enterica serovars are a major cause of foodborne illness and have a substantial impact on global human health. In Canada, Salmonella is commonly found on swine farms and the increasing concern about drug use and antimicrobial resistance associated with Salmonella has promoted research into alternative control methods, including selecting for pig genotypes associated with resistance to Salmonella. The objective of this study was to identify single-nucleotide variants in the pig genome associated with Salmonella susceptibility using a genome-wide association approach.

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Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus that can cause a hemorrhagic fever in humans, with a case fatality rate of up to 40%. Cases of CCHFV have been reported in Africa, Asia, and southern Europe; and recently, due to the expanding range of its vector, autochthonous cases have been reported in Spain. Although it was discovered over 70 years ago, our understanding of the pathogenesis of this virus remains limited.

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Objective/background: Elevated arterial stiffness is a characteristic of abdominal aortic aneurysm (AAA), and is associated with AAA growth and cardiovascular mortality. A bout of exercise transiently reduces aortic and systemic arterial stiffness in healthy adults. Whether the same response occurs in patients with AAA is unknown.

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Abdominal aortic aneurysm (AAA) is associated with inflammation and oxidative stress, the latter of which contributes to activation of macrophages, a prominent cell type in AAA. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been reported to limit oxidative stress in animal models of AAA. The aim of this study was to evaluate the effect of the n-3 PUFA docosahexaenoic acid (DHA) on antioxidant defence in macrophages from patients with AAA.

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Innate immune cell defects contribute to severe autoimmunity and the pathogenesis of inflammatory disease. Monocyte-derived macrophages typically retain disease related signatures and represent an excellent in vitro model to uncover and validate mechanisms contributing to specific pathological states. Monocyte isolation procedures vary widely in terms of purity, yield, cost, degree of technical difficulty and volume of peripheral blood needed.

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Article Synopsis
  • Abdominal aortic aneurysm (AAA) is a major health issue for older adults, and current treatments do not include drugs; inflammation and fatty acid imbalances may play a role in its development.
  • A study compared fatty acid levels in blood samples from 43 AAA patients and 52 healthy individuals, finding that AAA patients had lower levels of linoleic acid and increased production of arachidonic acid from linoleic acid.
  • In a trial involving 30 AAA patients, omega-3 fatty acid supplementation showed promise by reducing inflammation markers and improving fatty acid profiles after 12 weeks of treatment.
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Collagenous lectins are a family of soluble pattern recognition receptors that play an important role in innate immune resistance to infectious disease. Through recognition of carbohydrate motifs on the surface of pathogens, some collagenous lectins can activate the lectin pathway of complement, providing an effective means of host defense. Genetic polymorphisms in collagenous lectins have been shown in several species to predispose animals to a variety of infectious diseases.

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A 1-y-old spayed female ferret (Mustela putorius furo) was referred for additional diagnostic evaluation after physical examination by the referring veterinarian revealed a cranial abdominal mass. The ferret had a 2-wk history of inappetence, weight loss, and lethargy. On presentation, the ferret was thin, and an approximately 3-cm mass was palpable in the cranial abdomen.

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Markers of chronic inflammation increase with aging, and are associated with cardiovascular disease prevalence and mortality. Increases in fitness with exercise training have been associated with lower circulating concentrations of cytokines known to have pro-inflammatory actions (such as interleukin-6 [IL-6]) and higher circulating concentrations of anti-inflammatory cytokines (interleukin-10 [IL-10]). However, the effect of cardiorespiratory fitness on acute cytokine responses to a single bout of exercise in healthy older individuals is unknown.

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Purpose: Inflammation and extracellular matrix degeneration contribute to abdominal aortic aneurysm (AAA) development. We aimed to assess the effect of exercise intensity on circulating biomarkers of inflammation and extracellular matrix degeneration in patients with AAA and healthy older adults.

Methods: Twenty patients with AAA (74 ± 6 yr) and 20 healthy males (72 ± 5 yr) completed moderate-intensity cycling at 40% peak power output, higher-intensity intervals at 70% peak power output, and control (rest) on separate days.

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Background: Propolis and cerumen are plant-derived products found in honeybees and stingless bees, respectively. Although propolis is an ancient folk medicine, the bioactivities of cerumen obtained from Australian native stingless bees (Tetragonula carbonaria) have not been widely studied. Therefore, we investigated selected anti-oxidant and anti-inflammatory properties of T.

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