Publications by authors named "Macrae K"

Background: Vaccine mediated SARS-CoV-2 antibody responses should be carefully evaluated. With regular follow-up in healthy individuals, we aimed to determine SARS-CoV-2 serological responses post three doses of immunization and prior to breakthrough infections in the Canadian population.

Methods: In a prospective cohort study, we enrolled 140 healthy participants post COVID-19 vaccination in Kingston, Ontario, Canada.

View Article and Find Full Text PDF

(1) Background: COVID-19 vaccine effectiveness should be carefully evaluated and explicitly defined. To our knowledge, this is the first report to quantitatively evaluate humoral responses post 3 doses of SARS-CoV-2 immunization and prior to breakthrough COVID-19 infection in Canadian cancer patients. (2) Methods: In a prospective cohort study, we enrolled 185 cancer participants post COVID-19 vaccination in Kingston, Ontario, Canada.

View Article and Find Full Text PDF

Background: The process of developing patient management plans requires a series of clinical decision-making skills that can take years in practice to develop. For the inexperienced practitioner, providing a logical, systematic patient management framework may assist in clinical scenarios and accelerate their decision-making skill development. The purpose of this study was to assess whether a novel clinical management decision aid would improve the management decision-making of chiropractic students.

View Article and Find Full Text PDF

Purpose: Cardiovascular disease is the leading cause of mortality globally. Epicatechin has previously been shown to improve vascular responses and possess cardioprotective properties. However, the mechanisms underpinning these cardiotropic outcomes remain unknown.

View Article and Find Full Text PDF

We report a method for characterizing the focussing laser beam exiting the objective in a laser scanning microscope. This method provides the size of the optical focus, the divergence of the beam, the ellipticity and the astigmatism. We use a microscopic-scale knife edge in the form of a simple transmission electron microscopy grid attached to a glass microscope slide, and a light-collecting optical fibre and photodiode underneath the specimen.

View Article and Find Full Text PDF

Chronic exposure of skeletal muscle to saturated fatty acids, such as palmitate (C16:0), enhances proinflammatory IKK-NFκB signaling by a mechanism involving the MAP kinase (Raf-MEK-ERK) pathway. Raf activation can be induced by its dissociation from the Raf-kinase inhibitor protein (RKIP) by diacylglycerol (DAG)-sensitive protein kinase C (PKC). However, whether these molecules mediate the proinflammatory action of palmitate, an important precursor for DAG synthesis, is currently unknown.

View Article and Find Full Text PDF

Artificial weathering of Angolan crude and a Heavy Fuel Oil (HFO) was performed by evaporation and photooxidation. The aliphatic, aromatic, polar and asphaltene fractions of the fresh and weathered oils were isolated. The toxicity of the water accommodated fraction or an oil/fraction dissolved in DMSO was assessed using the sea urchin embryo test.

View Article and Find Full Text PDF

The relationship between glucose and lipid metabolism has been of significant interest in understanding the pathogenesis of obesity-induced insulin resistance. To gain insight into this metabolic paradigm, we explored the potential interplay between cellular glucose flux and lipid-induced metabolic dysfunction within skeletal muscle. Here, we show that palmitate (PA)-induced insulin resistance and proinflammation in muscle cells, which is associated with reduced mitochondrial integrity and oxidative capacity, can be attenuated under conditions of glucose withdrawal or glycolytic inhibition using 2-deoxyglucose (2DG).

View Article and Find Full Text PDF

Objectives: Financial stress has been identified as a barrier to antiretroviral adherence, but only in resource- limited settings. Almost half of HIV-infected Australian adults earn no regular income and, despite highly subsidised antiretroviral therapy and universal health care, 3% of HIV-infected Australians cease antiretroviral therapy each year. We studied the relationship between financial stress and treatment adherence in a resource-rich setting.

View Article and Find Full Text PDF

In recent decades, the antihyperglycemic biguanide metformin has been used extensively in the treatment of type 2 diabetes, despite continuing uncertainty over its direct target. In this article, using two independent approaches, we demonstrate that cellular actions of metformin are disrupted by interference with its metal-binding properties, which have been known for over a century but little studied by biologists. We demonstrate that copper sequestration opposes known actions of metformin not only on AMP-activated protein kinase (AMPK)-dependent signaling, but also on S6 protein phosphorylation.

View Article and Find Full Text PDF

Background: New antiretroviral drug classes provide opportunities to explore novel regimens.

Methods: HIV+ adults (<50 copies/mL) receiving atazanavir (ATV) were randomized to raltegravir (RAL) 400 mg + ATV 300 mg twice daily (q12h) for 4 weeks followed by RAL 800 mg + ATV/ritonavir 300/100 mg once daily (q24h) for 4 weeks or vice versa. Validated assays quantitated RAL and ATV plasma concentrations.

View Article and Find Full Text PDF

Freely dissolved pore water concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), penta- and hexachlorobenzene (PeCB and HCB), octachlorostyrene (OCS), p,p'-DDE and p,p'-DDD were measured in bottom sediments from three sites in Norway. Sediments were from Aker Brygge, site of a former shipyard in the inner part of Oslofjord, Frierfjord in the Grenlandsfjord area, impacted during the 50 year-long activity of a magnesium smelter plant, and from Kristiansand harbour, site with high industrial activity. Low density polyethylene (LDPE) membrane samplers were exposed to these sediments in laboratory incubation under constant and low-level agitation for periods of 1, 2, 6, 13, 23 and 50 days.

View Article and Find Full Text PDF

Background: Sustained exposure of pancreatic β cells to an increase in saturated fatty acids induces pleiotropic effects on β-cell function, including a reduction in stimulus-induced insulin secretion. The objective of this study was to investigate the effects of chronic over supply of palmitate upon glucose- and amino acid-stimulated insulin secretion (GSIS and AASIS, respectively) and autocrine-dependent insulin signalling with particular focus on the importance of ceramide, ERK and CaMKII signalling.

Principal Findings: GSIS and AASIS were both stimulated by >7-fold resulting in autocrine-dependent activation of protein kinase B (PKB, also known as Akt).

View Article and Find Full Text PDF

Sustained over-supply of saturated non-esterified 'free' fatty acids has been shown to promote skeletal muscle insulin resistance, which may be driven, in part, by an increase in inflammatory signalling within this tissue. In the present manuscript we show that exposure of L6 myotubes to palmitate, a saturated fatty acid, induces activation of the NF-κB (nuclear factor κB) pathway {based on increased IKK [IκB (inhibitory κB) kinase] phosphorylation, IκBα loss and elevated interleukin-6 mRNA expression} and that this was associated with enhanced phosphorylation/activation of p38 MAPK (mitogen-activated protein kinase), JNK (c-Jun N-terminal kinase) and ERK (extracellular-signal-regulated kinase) as well as impaired insulin-dependent activation of PKB (protein kinase B)/Akt and glucose transport. NF-κB activation by palmitate was unaffected by pharmacological inhibition of p38 MAPK or JNK, but was suppressed significantly by inhibition of MEK (MAPK/ERK kinase)/ERK signalling.

View Article and Find Full Text PDF

HIV treatment with CCR5 receptor blockers may impact CCR5(+) cell distribution. T cell subsets, plasmacytoid dendritic cells (PDC), and antigen-specific [Mycobacteria tuberculosis/avium (M.TB/MAI), cytomegalovirus (CMV), Herpes simplex (HSV), HIV-Gag] CD4(+) T cells were measured in untreated R5-tropic-HIV-infected adults receiving 10 days of SCH532706 (Phase 1), 15 days no therapy, then 10 days of cART (without SCH532706) (Phase 2).

View Article and Find Full Text PDF

We present an assessment of xenobiotic organic micro-pollutants (XOM) occurrence and removal of polycyclic aromatic hydrocarbons (PAHs) in a novel biofilm system combined with ozonation, the BIOZO concept, treating partly stabilised landfill leachate. A novel, staged moving-bed biofilm reactor (SMBBR) design was implemented in laboratory- and pilot-scale, and the PAHs removal efficiency of controlled ozonation was assessed installing the ozonation step in the nitrate recirculation line (Position 1) or between the pre-anoxic and aerobic zones (Position 2). COD removal in a laboratory- and in a pilot-scale SMBBR system with and without ozonation is additionally addressed.

View Article and Find Full Text PDF

Introduction: Whole-body vibration exposure may translate into improved bone mass in young adult women. The primary focus of this study was to examine the effects of graded whole-body vibration or vibration exposure plus resistance training on bone mineral density (BMD), hematological measures for bone remodeling, and exercise metabolism in young women.

Methods: There were 51 healthy active women [mean (SD) age, 21.

View Article and Find Full Text PDF

Background: SCH532706 is a novel small molecule chemokine receptor-5 (CCRS) antagonist with high in vitro potency (mean 90% inhibitory concentration [IC90] 0.15-7.0 nM) against diverse HIV type-1 (HIV-1) isolates.

View Article and Find Full Text PDF

For collaborative patient-centered practice models to develop, improved collaboration in the workplace is needed. In this project we aimed to create a model of continuing professional development (CPD) using a case based approach that would allow the exchange of information between primary health care providers in the community. Over 60 participants from community care sectors including physicians, nurses and administrators participated in a planning group and two consultation workshops.

View Article and Find Full Text PDF

Background: Toxicities observed with current combination antiretroviral therapy (CART) warrant a search for novel options, such as class-sparing regimens. Ritonavir-boosted double-protease inhibitor (PI)-only regimens are such an option but are prone to pharmacokinetic interactions.

Methods: This 48-week randomized study examined the safety and efficacy of a switch in CART to a once-daily regimen of saquinavir (SQV), ritonavir (RTV), and atazanavir (ATV) that did not include nucleoside reverse-transcriptase inhibitors (NRTIs).

View Article and Find Full Text PDF

Objective: The incidence of some cancers has been reported to be higher in diabetic patients than in the general population. We estimated the incidence of lung cancer in diabetic patients and investigated the hypothesis that the rate of lung cancer is different in diabetic compared with nondiabetic patients.

Research Design And Methods: Diabetic patients and age-, sex-, and general practice-matched nondiabetic control subjects were identified from U.

View Article and Find Full Text PDF

Although differences in self-conception across cultures have been well researched, regional differences within a culture have escaped attention. The present study examined individual, relational, and collective selves, which capture people's conceptions of themselves in relation to their goals, significant others, and in groups, comparing Australians and Japanese participants living in regional cities and metropolitan areas. Culture, gender, and urbanism were found to be related to individual, relational, and collective selves, respectively.

View Article and Find Full Text PDF

Background: Breast cancer has been considered a more indolent disease in the elderly, who are less tolerant of aggressive therapy. This trial tested the hypothesis that tamoxifen without surgery would provide adequate control of breast cancer for the remainder of life in elderly women, thereby sparing them surgery.

Method: Women aged over 70 years with operable, invasive breast cancer were randomized to receive either tamoxifen alone or surgery plus tamoxifen.

View Article and Find Full Text PDF

Background: Triptans are widely used to treat migraine but have been associated with stroke, myocardial infarction (MI), and ischemic heart disease (IHD) in case reports.

Objective: To estimate the incidence of stroke, cardiovascular events, and death in a migraine cohort, stratified by triptan prescription, and investigate whether the risk of these events was increased in those treated with triptans.

Methods: Migraine patients and matched nonmigraine control subjects were identified from the General Practice Research Database.

View Article and Find Full Text PDF