David Van Reyk

• Doctor of Philosophy
• Senior Lecturer at University of Technology Sydney

Using an opportunity where students were explicitly permitted to use artificial intelligence (AI) applications to prepare an assignment, we compared the practices and beliefs of two distinct student cohorts: second-year Science students at a large metropolitan university in Australia and students at a partner institution in the People's Republic of...

In the last decade, e-cigarette usage has increased, with an estimated 82 million e-cigarette users globally. This is, in part, due to the common opinion that they are “healthier” than tobacco cigarettes or simply “water vapour”. Third-hand e-vapour exposure is the chemical residue left behind from e-cigarette aerosols, which is of concern due to i...

Objective: Particulate matter (PM) with a diameter of 2.5 μm or less (PM2.5) can cross the blood-placental barrier causing adverse foetal outcomes. However, the impact of maternal exposure to low-levels of PM2.5 on liver health and the metabolic profile is unclear. This study aimed to investigate hepatic responses to long-term gestational low-dose...

We want to thank Bea Duric (10) for taking the time to read and comment on our study on the national differences regarding the experience of fully online and remote learning (1). Bea has drawn upon the experiences of learning during the pandemic at King’s College London, and we acknowledge Bea’s advocacy for her coursemates.

The COVID-19 pandemic has been a strong driver for moving more teaching and learning activities online. Border restrictions have had a severe impact on international students either hoping to enrol in courses offered in Australia or continue with such courses if they are already enrolled. The online learning experience is likely different between s...

Chronic airway inflammation and oxidative stress play crucial roles in the pathogenesis of chronic inflammatory lung diseases, with airway inflammation being a key driving mechanism of oxidative stress in the lungs. Inflammatory responses in the lungs activate neutrophils and/or eosinophils, leading to the generation of hypohalous acids (HOX). Thes...

Introduction: Bioavailability of nitric oxide (NO) is often compromised in early atherosclerosis, driving disease onset. This is usually due to dysfunctional endothelial nitric oxide synthase (eNOS). We have found that the transmembrane protein, FXYD1, is highly concentrated in the caveolae sub-cellular region and is closely associated with eNOS. O...

Pathophysiology describes and explains the physiological dysfunctions that occur in human diseases. Pathophysiology is content heavy, often leading to medical/biomedical science students adopting a surface approach to learning. To encourage more engagement, we developed clinical simulation practical classes using manikin patients. Students consider...

Background: Maternal smoking can lead to perturbations in central metabolic regulators such as neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) signalling components in offspring. With the growing interest in e-cigarettes as a tobacco replacement, this short report assessed central metabolic regulation in offspring of mouse dams exposed to e-c...

Atherosclerosis is characterised by the infiltration of macrophages at sites of inflammation within the vessel wall and the release of myeloperoxidase (MPO), which forms hypochlorous acid (HOCl) and hypothiocyanous acid (HOSCN). HOCl is a damaging oxidant implicated in the development of atherosclerosis. Preferential formation of HOSCN occurs under...

Chronic obstructive pulmonary disease (COPD) is a progressive disease of the lungs characterised by chronic inflammation, obstruction of airways, and destruction of the parenchyma (emphysema). These changes gradually impair lung function and prevent normal breathing. In 2002, COPD was the fifth leading cause of death, and is estimated by the World...

Low-density lipoprotein (LDL) modified by hypochlorous acid (HOCl) produced by myeloperoxidase (MPO) is present in atherosclerotic lesions, where it is implicated in the propagation of inflammation and acceleration of lesion development by multiple pathways, including the induction of endothelial dysfunction. Thiocyanate (SCN⁻) ions are utilised by...

Enrolled Nurses (EN) seeking to upgrade their qualification to Registered Nurse (RN) are commonly given direct entry into the second year of university pre-registration nursing degrees. This typically results in enrolment into science subjects including pathophysiology and pharmacology with the assumption that students have undertaken the requisite...

Employability development is a strategic priority for universities across advanced western economies. Despite this, there is no systematic study of employability development approaches internationally. In this study we considered how universities portray employability on the public pages of their websites. We undertook website content analysis of 1...

In Australia, many Enrolled Nurses (EN) complete vocational education training (VET), undertake clinical work, and then progress into a tertiary, Registered Nurse (RN), program. Transition into university for ENs is typically into the second year of degree programs, with credit awarded for first year courses including basic bioscience subjects, pre...

Does modern acupuncture address the clinical features of the original acupuncture theory? 1Victoria Choi, 1Deirdre Cobbin, 1Sean Walsh, 1Daivd Van Reyk 1University of Technology Sydney, Faculty of Science, School of Life Sciences Background: The seminal acupuncture text The Systematic Classic of Acupuncture and Moxibustion 282AD (SCoAaM) details...

There is strong evidence that low-density lipoprotein (LDL) modified by hypochlorous acid (HOCl) produced by myeloperoxidase is present in atherosclerotic lesions and can propagate inflammation. Less is known about the biological reactivity of LDL modified by hypothiocyanous acid (HOSCN), the other major oxidant produced by myeloperoxidase in vivo....

Teaching of pathophysiology concepts is a core feature in health professional programs, but it can be challenging in undergraduate medical/biomedical science education, which is often highly theoretical when delivered by lectures and pen-and-paper tutorials. Authentic case studies allow students to apply their theoretical knowledge but still requir...

Objectives: Maternal obesity imposes significant health risks in the offspring including diabetes and dyslipidemia. We previously showed that the hypoglycaemic agent exendin-4 (Ex-4) administered from weaning can reverse the maternal impact of 'transmitted disorders' in such offspring. However daily injection for six-weeks was required and the ben...

The nitroxide compound TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl radical) has been shown to prevent obesity-induced changes in adipokines in cell and animal systems. In this study we investigated whether supplementation with TEMPOL inhibits inflammation and atherosclerosis in apoE(-/-) mice fed a high fat diet (HFD). ApoE(-/-) mice wer...

Atherosclerosis is characterised by the accumulation of lipids within macrophages in the artery wall. Low-density lipoprotein (LDL) is the source of this lipid, owing to the uptake of oxidised LDL by scavenger receptors. Myeloperoxidase (MPO) released by leukocytes during inflammation produces oxidants that are implicated in atherosclerosis. Modifi...

Despite the value given to the teaching of bioscience as a central component of undergraduate nursing education, it has been accepted that nursing students often find bioscience subjects some of the most difficult to both master and perform well in. This nuts and bolts paper explores a practical approach undertaken to give first year students, comm...

Objective Carnosine has been shown to modulate triglyceride and glycation levels in cell and animal systems. In this study we investigated whether prolonged supplementation with carnosine inhibits atherosclerosis and markers of lesion stability in hyperglycaemic and hyperlipidaemic mice. Methods Streptozotocin-induced diabetic apo E−/− mice were m...

Students enrolled in the Bachelor of Nursing program come with diverse academic abilities, age, language skills and experience. Many enrol without any prior knowledge of the supporting sciences including chemistry. Moreover, whilst some do possess such prior knowledge, they may have had a substantial break since they last studied chemistry. This pa...

People with diabetes have an elevated risk of atherosclerosis. The accumulation of lipid within macrophage cells in the artery wall is believed to arise via the uptake and subsequent processing of modified low-density lipoproteins (LDL) via the endo-lysosomal system. In this study the effects of prolonged exposure to elevated glucose upon macrophag...

During atherosclerosis monocyte-derived macrophages accumulate cholesteryl esters from low-density lipoproteins (LDLs) via lectin-like oxidised LDL receptor-1 (LOX-1) and class AI and AII (SR-AI, SR-AII) and class B (SR-BI, CD36) scavenger receptors. Here we examined the hypothesis that hyperglycaemia may modulate receptor expression and hence lipi...

People with diabetes experience chronic hyperglycemia and are at a high risk of developing atherosclerosis and microvascular disease. Reactions of glucose, or aldehydes derived from glucose (e.g. methylglyoxal, glyoxal, or glycolaldehyde), with proteins result in glycation that ultimately yield advanced glycation end products (AGE). AGE are present...

Hypohalous acids are generated by activated leucocytes, via the formation of H(2)O(2) and the release of peroxidase enzymes (myeloperoxidase and eosinophil peroxidase). These species are important bactericidal agents, but HOCl (hypochlorous acid) and HOBr (hypobromous acid) have also been implicated in tissue damage in a number of inflammatory dise...

Nonenzymatic covalent binding (glycation) of reactive aldehydes (from glucose or metabolic processes) to low-density lipoproteins has been previously shown to result in lipid accumulation in a murine macrophage cell line. The formation of such lipid-laden cells is a hallmark of atherosclerosis. In this study, we characterize lipid accumulation in p...

Glycation of low-density lipoprotein (LDL) by reactive aldehydes, such as glycolaldehyde, can result in the cellular accumulation of cholesterol in macrophages. In this study, it is shown that carnosine, or its constituent amino acids beta-alanine and l-histidine, can inhibit the modification of LDL by glycolaldehyde when present at equimolar conce...

Previous studies have shown that glycation of LDL by methylglyoxal and glycolaldehyde, in the absence of significant oxidation, results in lipid accumulation in macrophage cells. Such 'foam cells' are a hallmark of atherosclerosis. In this study we examined whether LDL glycation by methylglyoxal or glycolaldehyde, and subsequent lipid loading of ce...

Oxysterols are the 27-carbon products of cholesterol oxidation by both enzymic and non-enzymic mechanisms. Their roles in cholesterol homeostasis, as well as in diseases in which oxidative damage and lipid peroxidation are implicated (e.g. atherosclerosis), have been investigated extensively. However, there are a number of important considerations...

Diabetes is known to induce a range of micro- and macrovascular complications, with the latter resulting in premature and accelerated atherosclerosis. Thus people with diabetes have a 2‐4-fold increased risk of developing cardiovascular diseases which is responsible for ca. 50% of deaths amongst people with diabetes. The mechanisms behind this elev...

This study tested the hypothesis that human macrophages have the ability to modify oxidation products in LDL and oxidized LDL (oxLDL) via a cellular antioxidant defence system. While many studies have focused on macrophage LDL oxidation in atherosclerosis development, less attention has been given to the cellular antioxidant capacity of these cells...

A prominent and early feature of the retinopathy of diabetes mellitus is a diffuse increase in vascular permeability. As the disease develops, the development of frank macular oedema may result in vision loss. That reactive oxygen species production is likely to be elevated in the retina, and that certain regions of the retina are enriched in subst...

Intracellular reactive oxygen species (ROS) production by activated murine T lymphocytes was investigated by analyzing intracellular dichlorofluorescin (DCFH(2)) oxidation in lymph node cells (LNC). An increase in DCFH(2) oxidation in LNC induced by phorbol myristate acetate (PMA) was detected by flow cytometry. It was confirmed that this increase...

The capacity of three novel iron chelators, namely 1-[N-ethoxycarbonylmethylpyridoxylidenium]-2-[2'-pyridyl]hydrazine bromide (EPH), 1-[5'-bromosalicylidene]-2-[2"-pyridyl]hydrazine (BsPH), and 1-pyridoxylidene-2-[1'-phthalazyl]hydrazine dihydrochloride (PPhH), to inhibit the proliferation of mitogen-stimulated murine lymph node cells was examined...

Lipid-laden macrophage foam cells are an early and persistent component of atherosclerotic lesions. As such they are likely to play a key role in disease progression, both as scavengers of lipid and as inflammatory mediators. The sterol content of macrophage foam cells is largely native cholesterol together with a small but significant proportion o...

Murine macrophages incubated in metal-supplemented RPMI could block or promote oxidation of low-density lipoprotein (LDL) depending on the degree of metal supplementation. Only at high concentrations of Cu (1 micromol/L) and Fe (30 micromol/L) were cells prooxidant, leading to an accelerated rate of LDL oxidation over that measured in comparable ce...

Oxidatively modified low density lipoprotein (LDL) has many biological activities which could contribute to the pathology of the atherosclerotic lesion. Because atherosclerosis has an inflammatory component, there has been much interest in the extent to which LDL could be oxidatively modified in vivo by inflammation. The present study examined LDL...

Oxidation of low density lipoprotein (LDL) results in changes to the lipoprotein that are potentially atherogenic. Numerous studies have shown that macrophages cultured in vitro can promote LDL oxidation via a transition metal-dependent process, yet the exact mechanisms that are responsible for macrophage-mediated LDL oxidation are not understood....

It was shown that the iron-selective chelator desferal (desferrioxamine mesylate:DFO) can reduce Cu(II) as judged by measuring the formation of the complex between Cu(I) and a specific chelator for this species, neocuproine (NC), in phosphate buffer. It was found that under optimal conditions, 3 moles of Cu(II) could be reduced per mole of DFO. Stu...

Removal of adventitious redox-active metals from buffers by treatment with Chelex resin is a widely used procedure in free radical research. Use of a new batch of Chelex-100 resin in our laboratory coincided with a sudden inability to oxidise low-density lipoprotein with copper. We found that copper-mediated oxidation of ascorbate in water treated...

A variety of anti-oxidants, including free radical scavengers and iron chelators, inhibit the proliferation of mitogenstimulated T lymphocytes in vitro. These agents do not operate by inhibiting the induction of omithine decarboxylase activity. Phorbol myristate acetate induces formation of reactive oxygen species in T cell-enriched populations. Fl...

The effects of three iron chelators (ADR-529/ICRF-187; omadine/pyrithione; and a newly synthesized pyridoxal-based iron chelator, SAG-15) on cultured BALB/c murine lymph node cells stimulated with phorbol myristate acetate and ionomycin have been investigated. All three agents were found to inhibit [3H]-thymidine incorporation after 66-72 h incubat...

Immunoelectron microscopy is an important tool used to determine the precise location of immune complexes. Standard concentrations of glutaraldehyde destroy these complexes. This paper describes a method in which the period of glutaraldehyde fixation is shortened by concomitant microwave treatment. Using 1.25% glutaraldehyde and microwave fixation...