Publications by authors named "Tallon C"

Integrating the voices of service users and providers in the design and delivery of health services increases the acceptability, relevance, and effectiveness of services. Such efforts are particularly important for youth opioid use treatments and services, which have failed to consider the unique needs of youth and families. Applying community-based participatory research (CBPR) and co-design can facilitate this process by contextualizing service user experiences at individual and community levels and supporting the collaborative design of innovative solutions for improving care.

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Background: Cognitive decline in Alzheimer's disease (AD) is associated with hyperphosphorylated tau (pTau) propagation between neurons along synaptically connected networks, in part via extracellular vesicles (EVs). EV biogenesis is triggered by ceramide enrichment at the plasma membrane from neutral sphingomyelinase2 (nSMase2)-mediated cleavage of sphingomyelin. We report, for the first time, that human tau expression elevates brain ceramides and nSMase2 activity.

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The progression of Alzheimer's disease (AD) correlates with the propagation of hyperphosphorylated tau (pTau) from the entorhinal cortex to the hippocampus and neocortex. Neutral sphingomyelinase2 (nSMase2) is critical in the biosynthesis of extracellular vesicles (EVs), which play a role in pTau propagation. We recently conjugated DPTIP, a potent nSMase2 inhibitor, to hydroxyl-PAMAM-dendrimer nanoparticles that can improve brain delivery.

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New Findings: What is the central question of this study? Gonadal hormones modulate cerebrovascular function while insulin-like growth factor 1 (IGF-1) facilitates exercise-mediated cerebral angiogenesis; puberty is a critical period of neurodevelopment alongside elevated gonadal hormone and IGF-1 activity: but whether exercise training across puberty enhances cerebrovascular function is unkown. What is the main finding and its importance? Cerebral blood flow is elevated in endurance trained adolescent males when compared to untrained counterparts. However, cerebrovascular reactivity to hypercapnia is faster in trained vs.

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The purpose of this study was to examine the effect of an acute bout of prolonged sitting with and without exercise breaks on cerebrovascular function in 7- to 13-year-old children. Forty-two children and adolescents were recruited to a crossover trial, with 15 girls (mean age 10.1 ± 2.

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Background: Youth (ages 12-24) rarely access services and supports to address substance use concerns. Peer support can facilitate service engagement and has been associated with positive substance use recovery outcomes in adults, yet few studies have examined this role among youth specifically. As such, this qualitative study explored the role of peer support in providing substance use services to youth in British Columbia and how best to support them in their role.

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Background: Cognitive decline in Alzheimer's disease (AD) is associated with prion-like tau propagation between neurons along synaptically connected networks, in part via extracellular vesicles (EV). EV biogenesis is triggered by ceramide enrichment at the plasma membrane from neutral sphingomyelinase2(nSMase2)-mediated cleavage of sphingomyelin. We report, for the first time, that tau expression triggers an elevation in brain ceramides and nSMase2 activity.

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Background: Substance use among youth is a longstanding global health concern that has dramatically risen in the era of highly toxic and unregulated drugs, including opioids. It is crucial to ensure that youth using unregulated opioids have access to evidence-based interventions, and yet, youth encounter critical gaps in the quality of such interventions. This study aims to address these gaps by identifying opportunities to improve the quality of opioid use services from the perspective of service providers, a perspective that has received scant attention.

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In the search for alternatives to 6-aminonicotinamide (6AN), a series of 6-aminonicotinic acid esters were designed and synthesized as precursors of 6-amino-NADP, a potent inhibitor of 6-phosphogluconate dehydrogenase (6PGD). Like 6AN, some of these esters were found to reverse the loss of histone 3 lysine 9 trimethylation (H3K9me3) in patient-derived pancreatic ductal adenocarcinoma (PDAC) distant metastasis (A38-5). Among them, 1-(((cyclohexyloxy)carbonyl)oxy)ethyl 6-aminonicotinate () showed more potent antiproliferative activity than 6AN.

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6-Diazo-5-oxo-l-norleucine (DON) is a glutamine antagonist that suppresses cancer cell metabolism but concurrently enhances the metabolic fitness of tumor CD8 T cells. DON showed promising efficacy in clinical trials; however, its development was halted by dose-limiting gastrointestinal (GI) toxicities. Given its clinical potential, we designed DON peptide prodrugs and found DRP-104 [isopropyl()-2-(()-2-acetamido-3-(1-indol-3-yl)-propanamido)-6-diazo-5-oxo-hexanoate] that was preferentially bioactivated to DON in tumor while bioinactivated to an inert metabolite in GI tissues.

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Alzheimer's disease (AD) is characterized by the progressive accumulation of amyloid-β and hyperphosphorylated tau (pTau), which can spread throughout the brain via extracellular vesicles (EVs). Membrane ceramide enrichment regulated by the enzyme neutral sphingomyelinase 2 (nSMase2) is a critical component of at least one EV biogenesis pathway. Our group recently identified 2,6-Dimethoxy-4-(5-Phenyl-4-Thiophen-2-yl-1H-Imidazol-2-yl)-Phenol (DPTIP), the most potent (30 nM) and selective inhibitor of nSMase2 reported to date.

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Maturational differences exist in cardiopulmonary and cerebrovascular function at sea-level, but the impact of maturation on acclimatization responses to high altitude is unknown. Ten children (9.8 ± 2.

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Purpose: A needs-based model of health systems planning uses a systematic estimate of service needs for a given population. Our objective was to derive annual prevalence estimates of specific mental disorders in the adult population of British Columbia, Canada and use a novel triangulation approach encompassing multiple data sources and stratifying these estimates by age, sex, and severity to inform Ministry partners, who commissioned this work.

Methods: We performed systematic literature reviews and subsequent meta-analyses to derive an annual prevalence estimate for each mental disorder.

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Intracranial blood velocity reactivity to a steady-state hypercapnic stimulus has been shown to be similar in children and adults, but the onset response to hypercapnia is slower in the child. Given the vasodilatory effect of hypercapnia on the cerebrovasculature, assessment of vessel diameter, and blood flow are vital to fully elucidate whether the temporal hypercapnic response differs in children versus adults. Assessment of internal carotid artery (ICA) vessel diameter (ICAd), blood velocity (ICAv), volumetric blood flow (Q ), and shear rate (ICA ) in response to a 4 min hypercapnic challenge was completed in children (n = 14, 8 girls; 9.

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Background: Substance use among youth (ages 12-24) is troublesome given the increasing risk of harms associated. Even more so, substance use services are largely underutilized among youth, most only accessing support when in crisis. Few studies have explored young people's help-seeking behaviours to address substance use concerns.

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Background: Evidence continues to show that young people, ages 15-24, remain at significant risk of harms from non-medical opioid use and opioid use disorder (OUD), with experts calling for widespread implementation of developmentally-appropriate interventions. These recommendations include the involvement of caregivers in the prevention, early intervention, and treatment of young people using opioids. However, little research has investigated caregivers' experiences supporting young people, leaving critical gaps in understanding this role.

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Background: Adolescence and young adulthood is an important period for substance use initiation and related harms. In the context of the ongoing opioid crisis, the risks for youth (ages 16-29) who use opioids are particularly heightened. Despite recommendations to adopt a developmentally appropriate and comprehensive approach to reduce opioid-related harms among youth, data continue to show that youth are not adequately engaged in opioid treatments and encounter many barriers.

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Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease where muscle weakness and neuromuscular junction (NMJ) denervation precede motor neuron cell death. Although acetylcholine is the canonical neurotransmitter at the mammalian NMJ synapse, glutamate has recently been identified as a critical neurotransmitter for NMJ development and maintenance. One source of glutamate is through the catabolism of N-acetyl-aspartyl-glutamate (NAAG), which is found in mM concentrations in mammalian motoneurons, where it is released upon stimulation and hydrolyzed to glutamate by the glial enzyme glutamate carboxypeptidase II (GCPII).

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Cognitive impairment is a common aspect of multiple sclerosis (MS) for which there are no treatments. Reduced brain -acetylaspartylglutamate (NAAG) levels are linked to impaired cognition in various neurological diseases, including MS. NAAG levels are regulated by glutamate carboxypeptidase II (GCPII), which hydrolyzes the neuropeptide to -acetyl-aspartate and glutamate.

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Three key challenges to a whole-system approach to process improvement in health systems are the complexity of socio-technical activity, the capacity to change purposefully, and the consequent capacity to proactively manage and govern the system. The literature on healthcare improvement demonstrates the persistence of these problems. In this project, the Access-Risk-Knowledge (ARK) Platform, which supports the implementation of improvement projects, was deployed across three healthcare organisations to address risk management for the prevention and control of healthcare-associated infections (HCAIs).

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Article Synopsis
  • Extracellular Vesicles (EVs) are linked to the spread of harmful proteins in neurological diseases, prompting research into inhibitors of neutral sphingomyelinase 2 (nSMase2), crucial for EV production.
  • Our team identified PDDC, a potent and selective nSMase2 inhibitor that can enter the brain and effectively lower EV release in both lab settings and living organisms.
  • In experiments with mice after brain injury, PDDC normalized nSMase2 activity and reduced specific types of EVs increased by inflammation, suggesting it could be a valuable treatment for acute brain injury.
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We explored the influence of sex and maturation on resting cervical artery hemodynamics (common carotid artery, CCA; internal carotid artery, ICA; and vertebral artery, VA), free-living physical activity, and sedentary behavior in children 6-17 yr of age. In addition, we investigated the relationship between physical activity, sedentary behavior, and cervical artery hemodynamics. Seventy-eight children and adolescents, girls ( = 42; mean age, 11.

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Background: Opioid use is one of the most critical public health issues as highly potent opioids contribute to rising rates of accidental opioid-related toxicity deaths. This crisis has affected people from all age groups, including youth (ages 15-24) who are in a critical developmental period where the stakes of opioid use are especially high. Efforts to reduce the significant harms of opioid use have focused on the expansion of evidence-based treatments, including medications for opioid use disorder (e.

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Endothelial cells are key regulators of transendothelial migration and their secretion of chemokines and expression of adhesion molecules facilitates lymphocyte entry into tissues. Previously, we demonstrated that Tregs can reduce transendothelial migration of T cells into tumors by decreasing endothelial CXCL10 secretion, but the mechanism by which this occurs is still not known. In this study, we aimed to define how Tregs decrease transendothelial migration into tumors.

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Objective: To estimate the prevalence of specific mental and substance use disorders (MSUDs), by age and sex, as a first step toward informing needs-based health systems planning by decision-makers.

Methods: We developed a conceptual framework and a systematic methodology for combining available data sources to yield prevalence estimates for specific MSUDs. Data sources used included published, peer-reviewed literature from Canada and comparable countries, Canadian population survey data, and health administrative data from British Columbia.

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