Publications by authors named "Jesse McLean"

Background: To ensure continuity of services while mitigating patient surge and nosocomial infections during the coronavirus disease 2019 (COVID-19) pandemic, acute care hospitals have been required to make significant operational adjustments. Here, we identify and discuss key administrative priorities and strategies utilized by a large community hospital located in Ontario, Canada.

Methods: Guided by a qualitative descriptive approach, we performed a thematic analysis of all COVID-19-related documentation discussed by the hospital's emergency operation centre (EOC) during the pandemic's first wave.

View Article and Find Full Text PDF

Background: Notably higher rates of mental health issues have been reported among healthcare providers (HCPs) during the COVID-19 pandemic. Concerns over the impact of policy decisions on the well-being of HCPs is growing, yet it remains underexplored in the literature.

Method: HCPs from a 301-bed mental health hospital and a 408-bed acute care community hospital, both located in central Ontario, participated in interviews (N = 30) and answered open-ended questionnaires (N = 88) to provide their experiences with the COVID-19 pandemic.

View Article and Find Full Text PDF

Background: Before the COVID-19 pandemic, healthcare providers (HCPs) were already experiencing a higher prevalence of mental health disorders compared with non-healthcare professionals. Here, we report on the psychosocial functioning and stress resilience of HCPs who worked during the COVID-19 pandemic in a large-sized psychiatric facility and a large acute care hospital, both located in central Ontario, Canada.

Methods: Participants completed five validated psychometric instruments assessing depression, anxiety, and stress (The Depression, Anxiety, and Stress Scale-21, DASS-21); work-related quality of life (Work-Related Quality of Life Scale, WRQoL); resilience (Connor-Davidson Resilience Scale, CD-RISC); anxiety about the novel coronavirus (Coronavirus Anxiety Scale, CAS); and loneliness (UCLA Loneliness Scale, ULS).

View Article and Find Full Text PDF

Background Oncoplastic partial mastectomy (OPM) is a technique utilized to improve aesthetic and survivorship outcomes in patients with localized breast cancer. This technique leads to breast tissue rearrangement, which can have an impact on target definition for boost radiotherapy (BRT). The aim of this study was to determine if the choice of surgical technique independently affected the decision to deliver a radiation boost.

View Article and Find Full Text PDF

Rituximab-associated infusion reactions (IRs) are significant burdens on oncology patients, caregivers and healthcare providers. We evaluated whether montelukast and rupatadine improve rituximab delivery, decrease frequency/severity of IRs and the number of medications used to control IRs. Using a nonrandomized clinical study design, we assessed adult rituximab naïve patients with B-cell lymphoid malignancies from January 2017 to July 2019.

View Article and Find Full Text PDF

Background: Oncoplastic surgery (OPS) is becoming the new standard of care for breast-conserving surgery (BCS). It has become increasingly popular in Europe; however, it has not yet been widely accepted in North America. This study aims to describe the experience with OPS at a Canadian tertiary care centre.

View Article and Find Full Text PDF

Background: Patients with a single hematological malignancy may be unexpectedly diagnosed with a clonally unrelated synchronous dual hematological malignancy (SDHM). The presence of a secondary hematological malignancy may be overlooked and only identified in situations presenting with discordant clinical or laboratory findings. Clinical management of these patients can be challenging, in part due to the relatively unknown etiopathology of SDHM and the impact of therapy on the secondary malignancy.

View Article and Find Full Text PDF

A hexanucleotide (G4C2) repeat expansion in the 5' non-coding region C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Three modes of toxicity have been proposed: gain of function through formation of RNA foci and sequestration of RNA binding proteins; expression of dipeptide repeat proteins generated by repeat-associated non-ATG translation; and loss of function due to C9orf72 haploinsufficiency. Much is known about the proposed gain of function mechanisms, but there is little knowledge of the normal function of C9orf72 and the cellular consequences if its activity is perturbed.

View Article and Find Full Text PDF

Diminished lysosomal function can lead to abnormal cellular accumulation of specific proteins, including α-synuclein, contributing to disease pathogenesis of vulnerable neurons in Parkinson's disease (PD) and related α-synucleinopathies. GBA1 encodes for the lysosomal hydrolase glucocerebrosidase (GCase), and mutations in GBA1 are a prominent genetic risk factor for PD. Previous studies showed that in sporadic PD, and in normal aging, GCase brain activity is reduced and levels of corresponding glycolipid substrates are increased.

View Article and Find Full Text PDF

Objective: A noncoding hexanucleotide repeat expansion in C9orf72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). It has been reported that the repeat expansion causes a downregulation of C9orf72 transcripts, suggesting that haploinsufficiency may contribute to disease pathogenesis. Two protein isoforms are generated from three alternatively spliced transcripts of C9orf72; a long form (C9-L) and a short form (C9-S), and their function(s) are largely unknown owing to lack of specific antibodies.

View Article and Find Full Text PDF

Aims: Loss-of-function mutations in GBA1, which cause the autosomal recessive lysosomal storage disease, Gaucher disease (GD), are also a key genetic risk factor for the α-synucleinopathies, including Parkinson's disease (PD) and dementia with Lewy bodies. GBA1 encodes for the lysosomal hydrolase glucocerebrosidase and reductions in this enzyme result in the accumulation of the glycolipid substrates glucosylceramide and glucosylsphingosine. Deficits in autophagy and lysosomal degradation pathways likely contribute to the pathological accumulation of α-synuclein in PD.

View Article and Find Full Text PDF

An expanded G4C2 repeat in C9orf72 represents the most common known genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). However, the lower limit for pathological expansions is unknown (the suggested cutoff is 30 repeats). It has been proposed that the expansion might have occurred only once in human history and subsequently spread throughout the population.

View Article and Find Full Text PDF

Dopaminergic neurons in the substantia nigra pars compacta (SNpc) are characterized by the expression of genes required for dopamine synthesis, handling and reuptake and the expression of these genes is largely controlled by nuclear receptor related 1 (Nurr1). Nurr1 is also expressed in astrocytes and microglia where it functions to mitigate the release of proinflammatory cytokines and neurotoxic factors. Given that Parkinson's disease (PD) pathogenesis has been linked to both loss of Nurr1 expression in the SNpc and inflammation, increasing levels of Nurr1 maybe a promising therapeutic strategy.

View Article and Find Full Text PDF

Peripherin is a type III intermediate filament protein, the expression of which is associated with the acquisition and maintenance of a terminally differentiated neuronal phenotype. Peripherin up-regulation occurs during acute neuronal injury and in degenerating motor neurons of amyotrophic lateral sclerosis. The functional role(s) of peripherin during normal, injurious, and disease conditions remains unknown, but may be related to differential expression of spliced isoforms.

View Article and Find Full Text PDF
Article Synopsis
  • Intracellular protein inclusions are key features in ALS, and their role is still unclear.
  • Peripherin, a protein associated with ALS, might lead to harmful inclusion formation due to abnormal splicing, resulting in aggregation-prone variants.
  • This study found that different peripherin forms create distinct inclusion types, affect protein expression, and may help protect against oxidative stress in nerve cells, highlighting their potential significance in ALS research.
View Article and Find Full Text PDF

Adeno-associated viral (AAV) gene transfer holds great promise for treating a wide-range of neurodegenerative disorders. The AAV9 serotype crosses the blood-brain barrier and shows enhanced transduction efficiency compared to other serotypes, thus offering advantageous targeting when global transgene expression is required. Neonatal intravenous or intracerebroventricular (i.

View Article and Find Full Text PDF

A long-term goal of modeling Huntington's disease (HD) is to recapitulate the cardinal features of the disease in mice that express both mutant and wild-type (WT) huntingtin (Htt), as HD commonly manifests as a heterozygous condition in humans, and loss of WT Htt is associated with loss-of-function. In a new heterozygous Q175 knock-in (KI) mouse model, we performed an extensive evaluation of motor and cognitive functional deficits, neuropathological and biochemical changes and levels of proteins involved in synaptic function, the cytoskeleton and axonal transport, at 1-16 months of age. Motor deficits were apparent at 6 months of age in Q175 KI mice and at that time, postmortem striatal gamma-aminobutyric acid (GABA) levels were elevated and mutant Htt inclusions were present throughout the brain.

View Article and Find Full Text PDF

Parkinson's disease (PD) is a common neurodegenerative disorder caused by genetic and environmental factors that results in degeneration of the nigrostriatal dopaminergic pathway in the brain. We analyzed neural cells generated from induced pluripotent stem cells (iPSCs) derived from PD patients and presymptomatic individuals carrying mutations in the PINK1 (PTEN-induced putative kinase 1) and LRRK2 (leucine-rich repeat kinase 2) genes, and compared them to those of healthy control subjects. We measured several aspects of mitochondrial responses in the iPSC-derived neural cells including production of reactive oxygen species, mitochondrial respiration, proton leakage, and intraneuronal movement of mitochondria.

View Article and Find Full Text PDF

While studying transgenic mice that overexpress human wildtype alpha-synuclein (Thy1-ASO, ASO) for typical brain alpha-synucleinopathy and central nervous system neuropathology, we observed progressive functional changes in the gastrointestinal and other peripheral organs. A more systematic study revealed that the gastrointestinal tract in ASO mice showed severe distension and blockage of the large intestine by 9-12 months of age. Functional assessments demonstrated a reduction in fecal water content and fecal pellet output, and increased whole gut transit time, in ASO mice compared to wildtype littermates, indicative of constipation, a symptom commonly reported by Parkinson's disease (PD) patients.

View Article and Find Full Text PDF

Alternative splicing is a complex post-transcriptional process that can be regulated by cis-acting elements located within genomic non-coding regions. Recent studies have identified that polymorphic variations in non-coding regions of the α-synuclein gene (SNCA) locus are associated with an increased risk for developing Parkinson's disease (PD). The underlying mechanism(s) for this susceptibility may involve changes in α-synuclein mRNA expression and alternative splicing.

View Article and Find Full Text PDF

The type III intermediate filament peripherin is found associated with pathological inclusions present within motor neurons of patients with amyotrophic lateral sclerosis (ALS). Peripherin intra-isoform associations contribute to filament network formation at defined stoichiometric ratios. Distinct biochemical signatures characterize peripherin isoform expression in traumatic neuronal injury and motor neuron disease, while disruptions to peripherin alternative splicing or translation are associated with inclusion formation.

View Article and Find Full Text PDF

Peripherin is a type III intermediate filament protein that is up-regulated during neuronal injury and is a major component of pathological inclusions found within degenerating motor neurons of patients with amyotrophic lateral sclerosis (ALS). The relationship between these inclusions and their protein constituents remains largely unknown. We have previously shown that peripherin expression is characterized by tissue-specific, intra-isoform associations that contribute to filament structure; changes to the normal isoform expression pattern is associated with malformed filaments and intracellular inclusions.

View Article and Find Full Text PDF

In NFL-/- mice, a model of motor neuron degeneration in ALS, degenerating spinal motor neurons express high levels of the receptor for the C5a anaphylatoxin (C5aR) early in the disease process. C5a is a potent in vitro neurotoxin for both Neuro2A and NGF-differentiated PC12 cells. While no interaction was observed between glutamate and C5a, both C5a and kainate upregulated the expression of activated C5aR.

View Article and Find Full Text PDF

The neuronal intermediate filament protein peripherin is a component of ubiquitinated inclusions and of axonal spheroids in amyotrophic lateral sclerosis (ALS). Overexpression of peripherin causes motor neuron degeneration in transgenic mice and variations within the peripherin gene have been identified in ALS cases. We have shown previously the abnormal expression of a neurotoxic peripherin splice variant in transgenic mice expressing mutant superoxide dismutase-1.

View Article and Find Full Text PDF

Peripherin is a type III neuronal intermediate filament protein detected within the intraneuronal inclusions characteristic of amyotrophic lateral sclerosis. The constitutively expressed peripherin isoform is encoded by all nine exons of the human and mouse peripherin genes to generate a protein species of approximately 58 kDa on sodium dodecyl sulfate-polyacrylamide gels. Expression of this isoform, termed Per-58, generates a filament network in transfected SW13 vim cells.

View Article and Find Full Text PDF