Background: Medical school involves high expectations of medical students, which may increase their risk for burnout. Physical activity (PA) and sedentary behaviour (SB) are modifiable risk factors for burnout. However, medical students are insufficiently taught about PA and SB and may therefore be less likely to meet guideline-recommended levels of these two movement behaviours or promote them in practice.
View Article and Find Full Text PDFObesity is a major health concern that is associated with altered gene transcription in the hypothalamus. However, the mechanisms controlling this gene expression dysregulation remain largely unknown. DNA 5-hydroxymethylation (5-hmC) is a potent transcriptional activator that is expressed at 10 times higher levels in the brain than the periphery.
View Article and Find Full Text PDFBackground: Health care providers have reported low knowledge, skill, and confidence for discussing movement behaviours (i.e., physical activity, sedentary behaviour, and sleep), which may be improved with the use of tools to guide movement behaviour discussions in their practice.
View Article and Find Full Text PDFBackground: The Coronavirus Disease 2019 (COVID-19) pandemic has exacerbated mental health challenges among physicians and non-physicians. However, it is unclear if the worsening mental health among physicians is due to specific occupational stressors, reflective of general societal stressors during the pandemic, or a combination. We evaluated the difference in mental health and addictions health service use between physicians and non-physicians, before and during the COVID-19 pandemic.
View Article and Find Full Text PDFObesity is a complex medical condition that is linked to various health complications such as infertility, stroke, and osteoarthritis. Understanding the neurobiology of obesity is crucial for responding to the etiology of this disease. The hypothalamus coordinates many integral activities such as hormone regulation and feed intake and numerous studies have observed altered hypothalamic gene regulation in obesity models.
View Article and Find Full Text PDFBackground: Canada's 24-Hour Movement Guidelines for Adults have shifted the focus from considering movement behaviours (i.e., physical activity, sedentary behaviour, and sleep) separately to a 24-h paradigm, which considers how they are integrated.
View Article and Find Full Text PDFStrong evidence has implicated proteasome-mediated protein degradation in the memory consolidation process. However, due to the use of pharmacological approaches, the cell type specificity of this remains unknown. Here, we used neuron-specific and novel astrocyte-specific CRISPR-dCas9-KRAB-MECP2 plasmids to inhibit protein degradation in a cell type-specific manner in the amygdala of male rats.
View Article and Find Full Text PDFImportance: Maintaining a healthy physician workforce includes the routine use of primary care physician (PCP) services; however, physicians may face barriers to attaining formal care.
Objective: To analyze access to and frequency of visits to PCPs among physicians compared with nonphysicians.
Design, Setting, And Participants: This population-based, retrospective cohort study used registration data from the College of Physicians and Surgeons of Ontario, Canada, from January 1, 1990, to March 31, 2018.
Objectives: Previous work has shown that exposure to a high fat diet dysregulates the protein degradation process in the hypothalamus of male rodents. However, whether this occurs in a sex-independent manner is unknown. The objective of this study was to determine the effects of a short-term obesogenic diet on the ubiquitin-proteasome mediated protein degradation process in the hypothalamus of female rats.
View Article and Find Full Text PDFImportance: Physicians self-report high levels of symptoms of anxiety and depression, and surveys suggest these symptoms have been exacerbated by the COVID-19 pandemic. However, it is not known whether pandemic-related stressors have led to increases in health care visits related to mental health or substance use among physicians.
Objective: To evaluate the association between the COVID-19 pandemic and changes in outpatient health care visits by physicians related to mental health and substance use and explore differences across physician subgroups of interest.
There is substantial evidence showing that medical student wellness is a worsening problem in Canada. It is apparent that medical students' wellness deteriorates throughout their training. Medical schools and their governing bodies are responding by integrating wellness into competency frameworks and accreditation standards through a combination of system- and individual-level approaches.
View Article and Find Full Text PDFBackground: Posttranslational histone modifications play a critical role in the regulation of gene transcription underlying synaptic plasticity and memory formation. One such epigenetic change is histone ubiquitination, a process that is mediated by the ubiquitin-proteasome system in a manner similar to that by which proteins are normally targeted for degradation. However, histone ubiquitination mechanisms are poorly understood in the brain and in learning.
View Article and Find Full Text PDFOver the last decade, strong evidence has emerged that protein degradation mediated by the ubiquitin-proteasome system is critical for fear memory formation in the amygdala. However, this work has been done primarily in males, leaving unanswered questions about whether females also require protein degradation during fear memory formation. Here, we found that male and female rats differed in their engagement and regulation of, but not need for, protein degradation in the amygdala during fear memory formation.
View Article and Find Full Text PDFNumerous studies have shown that following retrieval, a previously consolidated memory requires increased transcriptional regulation in order to be reconsolidated. Previously, it was reported that histone H3 lysine-4 trimethylation (H3K4me3), a marker of active transcription, is increased in the hippocampus after the retrieval of contextual fear memory. However, it is currently unknown how this epigenetic mark is regulated during the reconsolidation process.
View Article and Find Full Text PDFHealth Promot Chronic Dis Prev Can
October 2020
Depression is the most common and prevalent mental disorder today, affecting an estimated 1 in 4 Canadians at some point in their lifetime. Physical activity is recommended as a primary treatment for mild to moderate depression and a secondary treatment for moderate to severe depression. Despite this, specific guidelines are still lacking on how to best promote physical activity in this population.
View Article and Find Full Text PDFStudies have shown that long-term exposure to high fat and other obesogenic diets results in insulin resistance and altered blood brain barrier permeability, dysregulation of intracellular signaling mechanisms, changes in DNA methylation levels and gene expression, and increased oxidative stress and neuroinflammation in the hippocampus, all of which are associated with impaired spatial memory. The ubiquitin-proteasome system controls the majority of protein degradation in cells and is a critical regulator of synaptic plasticity and memory formation. Yet, whether protein degradation in the hippocampus becomes dysregulated following weight gain and is associated with obesity-induced memory impairments is unknown.
View Article and Find Full Text PDFRates of mental illness among Canadian medical students are higher than age-, gender-, and education-matched peers. One predictor of mental health is physical activity; though the relationship between different intensities of physical activity and mental health has not been investigated in medical students. The purpose of this study was to examine relationships between physical activity and mental health profiles in a sample of Canadian medical students.
View Article and Find Full Text PDFThe ubiquitin-proteasome system (UPS) controls the degradation of ~90% of short-lived proteins in cells and is involved in activity- and learning-dependent synaptic plasticity in the brain. Calcium/calmodulin dependent protein kinase II (CaMKII) and Protein Kinase A (PKA) can regulate activity of the proteasome. However, there have been a number of conflicting reports regarding under what conditions CaMKII and PKA regulate proteasome activity in the brain.
View Article and Find Full Text PDFBackground: Physical activity (PA) remains under prescribed by physicians. Motivation and confidence are clear drivers of frequency of promoting PA. Research shows demographic differences in physicians' preventive practices, yet none have included medical students who form habits during training.
View Article and Find Full Text PDFDespite the evidence supporting the benefits of physical activity in the prevention and treatment of most medical conditions, physical activity remains under-prescribed by physicians. Medical students will form habits during training that they are likely to maintain as future physicians. The overall purpose of this study was to investigate the underlying mechanism(s) contributing to frequency in recommending physical activity, to provide insight into how we can increase physical activity recommendations in future practice as physicians.
View Article and Find Full Text PDFThe ubiquitin-proteasome system is a key regulator of protein degradation and a variety of other cellular processes in eukaryotes. In the brain, increases in ubiquitin-proteasome activity are critical for synaptic plasticity and memory formation and aberrant changes in this system are associated with a variety of neurological, neurodegenerative and psychiatric disorders. One of the issues in studying ubiquitin-proteasome functioning in the brain is that it is present in all cellular compartments, in which the protein targets, functional role and mechanisms of regulation can vary widely.
View Article and Find Full Text PDFNumerous studies have supported a critical role for the ubiquitin-proteasome system (UPS) in the memory consolidation and reconsolidation processes. The protein targets and functional role of ubiquitin-proteasome activity can vary widely across cellular compartments, however, it is unknown how UPS activity changes within the nuclear, cytoplasmic, and synaptic regions in response to learning or memory retrieval. Additionally, while previous studies have focused on degradation-specific protein polyubiquitination, it is unknown how learning alters other polyubiquitin tags that are not targeted by the proteasome.
View Article and Find Full Text PDFThis article presents secondary outcome variables from a randomized controlled trial evaluating the efficacy of two guided self-help interventions for the treatment of depression: behavioral activation (BA) and physical activity (PA). Both interventions resulted in significant reductions in depressive symptoms compared to the wait-list control group, however the mechanisms by which these interventions influenced depression were not presented. The purpose of this paper was to compare changes in secondary outcome variables to gain insight into the mechanisms by which reactivation interventions reduce depressive symptoms.
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