Publications by authors named "Stuart Morgan"

Article Synopsis
  • Systemic excess of glucocorticoids, such as in Cushing's syndrome, leads to various metabolic issues, influenced by the enzyme 11β-HSD1.
  • A study on mice revealed that high doses of corticosterone increased metabolic rates and carbohydrate use, especially in female wild type (WT) mice, but also caused fat accumulation.
  • Notably, 11β-HSD1 knockout mice were protected from these metabolic changes, highlighting its role in the effects of glucocorticoid excess and hyperphagia.
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Background: To overcome deficiencies of the traditional von Willebrand factor (VWF) ristocetin cofactor activity assay (VWF:RCo), several automated assays for VWF platelet-binding activity have been developed. Information on the performance of these assays and their diagnostic utility remains limited.

Objectives: To validate the VWF:glycoprotein IbM assay INNOVANCE VWF Ac and compare it with an automated VWF:RCo assay as well as with an automated assay and a manual VWF:Ab assay and to generate reference ranges and analyze reproducibility of the VWF:glycoprotein IbM assay.

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The aged phenotype shares several metabolic similarities with that of circulatory glucocorticoid excess (Cushing's syndrome), including type 2 diabetes, obesity, hypertension, and myopathy. We hypothesise that local tissue generation of glucocorticoids by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts 11-dehydrocorticosterone to active corticosterone in rodents (corticosterone to cortisol in man), plays a role in driving age-related chronic disease. In this study, we have examined the impact of ageing on glucocorticoid metabolism, insulin tolerance, adiposity, muscle strength, and blood pressure in both wildtype (WT) and transgenic male mice with a global deletion of 11β-HSD1 (11β-HSD1-/-) following 4 months high-fat feeding.

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Numerous state-of-the-art solutions for neural speech decoding and synthesis incorporate deep learning into the processing pipeline. These models are typically opaque and can require significant computational resources for training and execution. A deep learning architecture is presented that learns input bandpass filters that capture task-relevant spectral features directly from data.

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Patients with growth hormone deficiency (GHD) have many clinical features in common with Cushing's syndrome (glucocorticoid excess) - notably visceral obesity, insulin resistance, muscle myopathy and increased vascular mortality. Within key metabolic tissues, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts cortisone to the active glucocorticoid, cortisol (11-dehydrocorticosterone and corticosterone in rodents respectively), and thus amplifies local glucocorticoid action. We hypothesize that 11β-HSD1 expression is negatively regulated by growth hormone (GH), and that GHD patients have elevated 11β-HSD1 within key metabolic tissues (leading to increased intracellular cortisol generation) which contributes to the clinical features of this disease.

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Electrohydrodynamic atomisation (EHDA) technologies have evolved significantly over the past decade; branching into several established and emerging healthcare remits through timely advances in the engineering sciences and tailored conceptual process designs. More specifically for pharmaceutical and drug delivery spheres, electrospraying (ES) has presented itself as a high value technique enabling a plethora of different particulate structures. However, when coupled with novel formulations (e.

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Background: Direct factor Xa (FXa) inhibitors are increasingly prescribed for outpatients, and those transitioning to unfractionated heparin (UFH) for hospital admission are monitored via an anti-FXa assay. Because of assay interference, UFH results would often be critically elevated, confounding dosing.

Objectives: An anti-factor IIa (FIIa) UFH assay was evaluated for clinical use.

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Electrohydrodynamic atomization (EHDA) is an emerging technique for the production of micron and nano-scaled particles. The process often involves Taylor cone enablement, which results in a fine spray yielding formulated droplets, which then undergo drying during deposition. In this work, novel multi-tip emitter (MTE) devices were designed, engineered and utilized for potential up-scaled EHDA, by comparison with a conventional single-needle system.

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The external load of a team-sport athlete can be measured by tracking technologies, including global positioning systems (GPS), local positioning systems (LPS), and vision-based systems. These technologies allow for the calculation of displacement, velocity and acceleration during a match or training session. The accurate quantification of these variables is critical so that meaningful changes in team-sport athlete external load can be detected.

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Glucocorticoids (GCs) have unparalleled anti-inflammatory and immunosuppressive properties, which accounts for their widespread prescription and use. Unfortunately, a limitation to GC therapy is a wide range of negative side effects including Cushing's syndrome, a disease characterized by metabolic abnormalities including muscle wasting and osteoporosis. GC-induced osteoporosis occurs in 30% to 50% of patients on GC therapy and thus, represents an important area of study.

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The aim of this study was to determine the high-speed running and sprinting profiles of elite female soccer players during competitive matches using a new Optical Player Tracking system. Eight stationary video cameras were positioned at vantage points surrounding the soccer field so that when each camera view was combined, the entire field could be viewed simultaneously. After each match, an optical player tracking system detected the coordinates (x, y) of each player for every video frame.

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Glucocorticoids (GCs) are potent regulators of energy metabolism. Chronic GC exposure suppresses brown adipose tissue (BAT) thermogenic capacity in mice, with evidence for a similar effect in humans. Intracellular GC levels are regulated by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity, which can amplify circulating GC concentrations.

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Athlete external load is typically analysed from predetermined movement thresholds. The combination of movement sequences and differences in these movements between playing positions is also currently unknown. This study developed a method to discover the frequently recurring movement sequences across playing position during matches.

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Age-associated decline in muscle function represents a significant public health burden. Vitamin D-deficiency is also prevalent in aging subjects, and has been linked to loss of muscle mass and strength (sarcopenia), but the precise role of specific vitamin D metabolites in determining muscle phenotype and function is still unclear. To address this we quantified serum concentrations of multiple vitamin D metabolites, and assessed the impact of these metabolites on body composition/muscle function parameters, and muscle biopsy gene expression in a retrospective study of a cohort of healthy volunteers.

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Objectives: The aim of this study was to determine the acceleration (≥2ms) and deceleration (≤-2ms) profiles of elite female soccer players during competitive matches.

Design: Single cohort, observational study.

Methods: An Optical Player Tracking system was used to determine acceleration (≥2ms) and deceleration (≤-2ms) variables for twelve elite female players across seven competitive matches.

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Muscle wasting is a common feature of inflammatory myopathies. Glucocorticoids (GCs), although effective at suppressing inflammation and inflammatory muscle loss, also cause myopathy with prolonged administration. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) is a bidirectional GC-activating enzyme that is potently upregulated by inflammation within mesenchymal-derived tissues.

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Nonalcoholic fatty liver disease (NAFLD) defines a spectrum of conditions from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis and is regarded as the hepatic manifestation of the metabolic syndrome. Glucocorticoids can promote steatosis by stimulating lipolysis within adipose tissue, free fatty acid delivery to liver and hepatic de novo lipogenesis. Glucocorticoids can be reactivated in liver through 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme activity.

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The adverse metabolic effects of prescribed and endogenous glucocorticoid excess, 'Cushing's syndrome', create a significant health burden. While skeletal muscle atrophy and resultant myopathy is a clinical feature, the molecular mechanisms underpinning these changes are not fully defined. We have characterized the impact of glucocorticoids upon key metabolic pathways and processes regulating muscle size and mass including: protein synthesis, protein degradation, and myoblast proliferation in both murine C2C12 and human primary myotube cultures.

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The purpose of this study was to probe the sex-based differences in the stroke and movement dynamics of Grand Slam hard-court tennis. Player and ball tracking data were collated for 102 male and 95 female players during the 2012-2014 Australian Open tournaments. Serve, serve return, groundstroke and movement data were compared between sexes.

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Glucocorticoids are widely prescribed for their anti-inflammatory properties, but have 'Cushingoid' side effects including visceral obesity, muscle myopathy, hypertension, insulin resistance, type 2 diabetes mellitus, osteoporosis, and hepatic steatosis. These features are replicated in patients with much rarer endogenous glucocorticoid (GC) excess (Cushing's syndrome), which has devastating consequences if left untreated. Current medical therapeutic options that reverse the tissue-specific consequences of hypercortisolism are limited.

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Background: Anemia adversely affects cerebral oxygenation and metabolism after subarachnoid hemorrhage (SAH) and is also associated with poor outcome. There is limited evidence to support the use of packed red blood cell (PRBC) transfusion to optimize brain homeostasis after SAH. The aim of this study was to investigate the effect of transfusion on cerebral oxygenation and metabolism in patients with SAH.

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Context: Cushing's syndrome is characterized by marked changes in body composition (sarcopenia, obesity, and osteoporosis) that have similarities with those seen in aging. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts glucocorticoids to their active form (cortisone to cortisol in humans), resulting in local tissue amplification of effect.

Objective: To evaluate 11β-HSD1 expression and activity with age, specifically in muscle.

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Peripartum, and especially during the transition period, dairy cows undergo dramatic physiological changes. These coincide with an increased risk of disease during the first 2 wk after calving and have been linked to dairy cows failing to achieve production as well as reproductive targets. Previous evidence suggests that these physiological changes affect the immune system and that transition dairy cows experience some form of reduced immunocompetence.

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11β-Hydroxysteroid dehydrogenase-1 (11β-HSD1) plays a key role in glucocorticoid receptor (GR) activation. Besides, it metabolizes some oxysterols and bile acids (BAs). The GR regulates BA homeostasis; however, the impact of impaired 11β-HSD1 activity remained unknown.

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The adverse metabolic effects of prescribed and endogenous glucocorticoid (GC) excess, Cushing syndrome, create a significant health burden. We found that tissue regeneration of GCs by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), rather than circulating delivery, is critical to developing the phenotype of GC excess; 11β-HSD1 KO mice with circulating GC excess are protected from the glucose intolerance, hyperinsulinemia, hepatic steatosis, adiposity, hypertension, myopathy, and dermal atrophy of Cushing syndrome. Whereas liver-specific 11β-HSD1 KO mice developed a full Cushingoid phenotype, adipose-specific 11β-HSD1 KO mice were protected from hepatic steatosis and circulating fatty acid excess.

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