474 results match your criteria: "The Heart Research Institute.[Affiliation]"

Background: It is reported that glaucoma may be associated with vascular dysregulation. Normal tension glaucoma (NTG) and primary open angle glaucoma (POAG), which feature different intraocular pressure levels, may manifest differential features of systemic autonomic dysregulation.

Methods And Results: We investigated autonomic regulation to carbohydrate ingestion and postural change in 37 glaucoma patients (19 NTG and 18 POAG) and 36 controls.

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Almost 600 million people are predicted to have diabetes mellitus (DM) by 2035. Diabetic patients suffer from increased rates of microvascular and macrovascular complications, associated with dyslipidaemia, impaired angiogenic responses to ischaemia, accelerated atherosclerosis, and inflammation. Despite recent treatment advances, many diabetic patients remain refractory to current approaches, highlighting the need for alternative agents.

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Background: Induced pluripotent stem-cell derived endothelial cells (iPSC-ECs) can be generated from any somatic cell and their iPSC sources possess unlimited self-renewal. Previous demonstration of their proangiogenic activity makes them a promising cell type for treatment of ischemic injury. As with many other stem cell approaches, the low rate of in-vivo survival has been a major limitation to the efficacy of iPSC-ECs to date.

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Superoxide radicals react with peptide-derived tryptophan radicals with very high rate constants to give hydroperoxides as major products.

Free Radic Biol Med

April 2018

The Heart Research Institute, Sydney, Australia; Sydney Medical School, University of Sydney, Australia; Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Denmark. Electronic address:

Oxidative damage is a common process in many biological systems and proteins are major targets for damage due to their high abundance and very high rate constants for reaction with many oxidants (both radicals and two-electron species). Tryptophan (Trp) residues on peptides and proteins are a major sink for a large range of biological oxidants as these side-chains have low radical reduction potentials. The resulting Trp-derived indolyl radicals (Trp) have long lifetimes in some circumstances due to their delocalized structures, and undergo only slow reaction with molecular oxygen, unlike most other biological radicals.

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High-density lipoproteins augment hypoxia-induced angiogenesis by inducing the key angiogenic vascular endothelial growth factor A (VEGFA) and total protein levels of its receptor 2 (VEGFR2). The activation/phosphorylation of VEGFR2 is critical for mediating downstream, angiogenic signaling events. This study aimed to determine whether reconstituted high-density lipoprotein (rHDL) activates VEGFR2 phosphorylation and the downstream signaling events and the importance of VEGFR2 in the proangiogenic effects of rHDL in hypoxia.

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Exposure of tropoelastin to peroxynitrous acid gives high yields of nitrated tyrosine residues, di-tyrosine cross-links and altered protein structure and function.

Free Radic Biol Med

February 2018

The Heart Research Institute, Sydney, Australia; Dept. of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark; Faculty of Medicine, University of Sydney, Sydney, Australia. Electronic address:

Elastin is an abundant extracellular matrix protein in elastic tissues, including the lungs, skin and arteries, and comprises 30-57% of the aorta by dry mass. The monomeric precursor, tropoelastin (TE), undergoes complex processing during elastogenesis to form mature elastic fibres. Peroxynitrous acid (ONOOH), a potent oxidising and nitrating agent, is formed in vivo from superoxide and nitric oxide radicals.

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Targeted Modulation of Tropoelastin Structure and Assembly.

ACS Biomater Sci Eng

November 2017

Charles Perkins Centre, School of Life and Environmental Sciences, School of Physics, Sydney Medical School, and Bosch Institute, The University of Sydney, Sydney, New South Wales 2006, Australia.

Tropoelastin, as the monomer unit of elastin, assembles into elastic fibers that impart strength and resilience to elastic tissues. Tropoelastin is also widely used to manufacture versatile materials with specific mechanical and biological properties. The assembly of tropoelastin into elastic fibers or biomaterials is crucially influenced by key submolecular regions and specific residues within these domains.

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The effect of acetyl salicylic acid (Aspirin) on trophoblast-endothelial interaction in vitro.

J Reprod Immunol

November 2017

Vascular Immunology Research Laboratory, The Heart Research Institute, University of Sydney, Australia; School of Medicine, Western Sydney University, Sydney, Australia; Renal Unit, Liverpool Hospital, Sydney, Australia.

Early administration of low dose acetyl salicylic acid (Aspirin) in high risk women reduces the risk of early onset preeclampsia. This study aims to investigate the effect of aspirin on trophoblast integration and the its effect on angiogenic and invasive pathways in an in-vitro model of preeclampsia. Red fluorescent-labeled human uterine myometrial microvascular endothelial cells (UtMVECs) were seeded on matrigel to form endothelial networks.

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Colchicine Therapy and Plaque Stabilization in Patients With Acute Coronary Syndrome: A CT Coronary Angiography Study.

JACC Cardiovasc Imaging

February 2018

Department of Cardiology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia; Sydney Medical School, The University of Sydney, New South Wales, Australia; The Heart Research Institute, Sydney, New South Wales, Australia; Charles Perkins Centre, The University of Sydney, New South Wales, Australia. Electronic address:

Objectives: The authors sought to evaluate the plaque-modifying effects of low-dose colchicine therapy plus optimal medical therapy (OMT) in patients post-acute coronary syndrome (ACS), as assessed by coronary computed tomography angiography (coronary CTA).

Background: Colchicine therapy has been postulated to have beneficial anti-inflammatory effects in patients with ACS, translating into reduction in future adverse cardiovascular events. However, whether favorable plaque modification underpins this is yet unproven.

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Formation and detection of oxidant-generated tryptophan dimers in peptides and proteins.

Free Radic Biol Med

December 2017

The Heart Research Institute, Newtown, Australia; Sydney Medical School, University of Sydney, Australia; Panum Institute, University of Copenhagen, Denmark. Electronic address:

Free radicals are produced during physiological processes including metabolism and the immune response, as well as on exposure to multiple external stimuli. Many radicals react rapidly with proteins resulting in side-chain modification, backbone fragmentation, aggregation, and changes in structure and function. Due to its low oxidation potential, the indole ring of tryptophan (Trp) is a major target, with this resulting in the formation of indolyl radicals (Trp).

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Low-density lipoprotein modified by myeloperoxidase oxidants induces endothelial dysfunction.

Redox Biol

October 2017

The Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia; Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Blegdamsvej 3, Copenhagen N 2200, Denmark. Electronic address:

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 MPO to produce the oxidant hypothiocyanous acid (HOSCN), which reacts with LDL in a different manner to HOCl. Whilst the reactivity of HOCl-modified LDL has been previously studied, the role of HOSCN in the modification of LDL in vivo is poorly defined, although emerging evidence suggests that these particles have distinct biological properties.

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Key Points: Glutamatergic neurons in the median preoptic area were stimulated using genetically targeted Channelrhodopsin 2 in transgenic mice. Stimulation of glutamatergic median preoptic area neurons produced a profound hypothermia due to cutaneous vasodilatation. Stimulation also produced drinking behaviour that was inhibited as water was ingested, suggesting pre-systemic feedback gating of drinking.

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The nitroxide 4-methoxy TEMPO inhibits neutrophil-stimulated kinase activation in H9c2 cardiomyocytes.

Arch Biochem Biophys

September 2017

Discipline of Pathology, Charles Perkins Centre, Sydney Medical School, The University of Sydney, NSW 2006, Australia. Electronic address:

After acute myocardial infarction (AMI), neutrophils are recruited to the affected myocardium. Hypochlorous acid (HOCl) produced by neutrophil myeloperoxidase (MPO) damages cardiomyocytes and potentially expands the primary infarct. Rat cardiomyocyte-like cells were incubated with isolated human neutrophils treated with chemical activators in the absence or presence of nitroxide 4-methoxy-Tempo (MetT; 25 μM) for 4, 6 or 24 h; studies with reagent HOCl served as positive control.

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Plasma activated coating immobilizes apolipoprotein A-I to stainless steel surfaces in its bioactive form and enhances biocompatibility.

Nanomedicine

October 2017

The Heart Research Institute, Sydney, New South Wales, Australia; Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia. Electronic address:

We utilized a plasma activated coating (PAC) to covalently bind the active component of high density lipoproteins (HDL), apolipoprotein (apo) A-I, to stainless steel (SS) surfaces. ApoA-I suppresses restenosis and thrombosis and may therefore improve SS stent biocompatibility. PAC-coated SS significantly increased the covalent attachment of apoA-I, compared to SS alone.

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The Utility of Cardiac Magnetic Resonance Imaging in the Diagnosis of Cardiac Sarcoidosis.

Heart Lung Circ

November 2017

Cardiology Department, Royal Prince Alfred Hospital, Sydney, NSW, Australia; Sydney Medical School, the University of Sydney, Sydney, NSW, Australia.

Background: Autopsy reports suggest that cardiac sarcoidosis occurs in 20 to 25% of patients with pulmonary sarcoidosis, yet the clinical ante-mortem diagnosis is made in only 5% of cases. Current diagnostic algorithms are complex and lack sensitivity. Cardiac Magnetic Resonance imaging (CMR) provides an opportunity to detect myocardial involvement in sarcoidosis.

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Estrogen Receptor Control of Atherosclerotic Calcification and Smooth Muscle Cell Osteogenic Differentiation.

Arterioscler Thromb Vasc Biol

June 2017

From the Heart Research Institute, Sydney, New South Wales, Australia (L.S.M., K.C.Y.M., T.T., E.C.L., J.T.M.T.); Department of Clinical Medicine, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales, Australia (L.S.M.); School of Life Sciences, Faculty of Science, University of Technology Sydney, New South Wales, Australia (K.C.Y.M.); Sydney Medical School (J.T.M.T.) and ANZAC Research Institute (D.J.H.), University of Sydney, New South Wales, Australia; and Department of Physiology, Otago School of Medical Sciences (G.H., A.K.H.) and HeartOtago (A.K.H.), University of Otago, Dunedin, New Zealand.

Objective: Vascular calcification is associated with increased risk of myocardial infarction and stroke. The objective of this work was to examine the ability of 17β-estradiol (E2) to stimulate calcification of vascular smooth muscle cells (VSMC) in vivo, using aged apolipoprotein E-null mice with advanced atherosclerotic lesions, and subsequently to explore underlying mechanisms in vitro.

Approach And Results: Silastic E2 capsules were implanted into male and female apolipoprotein E-null mice aged 34 weeks.

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Catalytic oxidant scavenging by selenium-containing compounds: Reduction of selenoxides and N-chloramines by thiols and redox enzymes.

Redox Biol

August 2017

The Heart Research Institute, 7 Eliza St, Newtown, NSW 2042, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia; Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Blegdamsvej 3, Copenhagen N 2200, Denmark. Electronic address:

Myeloperoxidase produces strong oxidants during the immune response to destroy invading pathogens. However, these oxidants can also cause tissue damage, which contributes to the development of numerous inflammatory diseases. Selenium containing compounds, including selenomethionine (SeMet) and 1,4-anhydro-5-seleno-D-talitol (SeTal), react rapidly with different MPO-derived oxidants to form the respective selenoxides (SeMetO and SeTalO).

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Improving Guideline Compliance in Australia With a National Percutaneous Coronary Intervention Outcomes Registry.

Heart Lung Circ

December 2017

Cardiologist and Director of the Heart Research Institute Sir Charles Gairdner Hospital Clinical Professor of Medicine University of Western Australia Deputy Director, Harry Perkins Institute of Medical Research, Perth, WA, Australia. Electronic address:

Background: Secondary prevention strategies after percutaneous coronary intervention (PCI) include statins and dual anti-platelet therapy, however there are significant gaps between guidelines and practice. Contemporary PCI practice requires comprehensive data collection to allow dynamic auditing and benchmarking of key performance and safety indices. Genesis HeartCare is Australia's largest collaborative venture of cardiologists, practising at over 40 public and private hospitals.

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Current animal models for the evaluation of synthetic grafts are lacking many of the molecular tools and transgenic studies available to other branches of biology. A mouse model of vascular grafting would allow for the study of molecular mechanisms of graft failure, including in the context of clinically relevant disease states. In this study, we comprehensively characterise a sutureless grafting model which facilitates the evaluation of synthetic grafts in the mouse carotid artery.

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Inhibition of microglial activation with minocycline at the intrathecal level attenuates sympathoexcitatory and proarrhythmogenic changes in rats with chronic temporal lobe epilepsy.

Neuroscience

May 2017

The Heart Research Institute, 7 Eliza Street, Sydney 2042 New South Wales, Australia; Department of Physiology, University of Sydney, Sydney 2006 New South Wales, Australia. Electronic address:

The incidence of sudden unexpected death in epilepsy (SUDEP) is highest in people with chronic and drug-resistant epilepsy. Chronic spontaneous recurrent seizures cause cardiorespiratory autonomic dysfunctions. Pituitary adenylate cyclase-activating polypeptide (PACAP) is neuroprotective, whereas microglia produce both pro- and anti-inflammatory effects in the CNS.

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Mitochondria are a major source of intracellular energy and reactive oxygen species in cells, but are also increasingly being recognized as a controller of cell death. Here, we review evidence of signal transduction control by mitochondrial superoxide generation via the nuclear factor-κB (NF-κB) and GATA signaling pathways. We have also reviewed the effects of ROS on the activation of MMP and HIF.

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Non-invasive tracking of injected bone marrow mononuclear cells to injury and implanted biomaterials.

Acta Biomater

April 2017

The Heart Research Institute, Sydney, NSW 2042, Australia; School of Life & Environmental Science, University of Sydney, NSW 2006, Australia; Royal Prince Alfred Hospital, Sydney, NSW 2042, Australia. Electronic address:

Unlabelled: Biomaterial scaffolds enhancing the engraftment of transplanted bone-marrow mononuclear cells (BM-MNC) have enormous potential for tissue regeneration applications. However, development of appropriate materials is challenging given the precise microenvironments required to support BM-MNC engraftment and function. In this study, we have developed a non-invasive, real-time tracking model of injected BM-MNC engraftment to wounds and implanted biomaterial scaffolds.

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Medications used to control hypertension in pregnancy also improve trophoblast and endothelial cellular interaction in vitro. Tumour necrosis factor-α (TNF-α) inhibits trophoblast and endothelial cellular interactions and simultaneously decreases endothelial nitric oxide synthase (eNOS) expression. This study investigated whether antihypertensive medications improved these cellular interactions by modulating eNOS and inducible nitric oxide synthase (iNOS) expression.

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Low-density lipoprotein (LDL) is the major source of lipid within atherosclerotic lesions. Myeloperoxidase (MPO) is present in lesions and forms the reactive oxidants hypochlorous acid (HOCl) and hypothiocyanous acid (HOSCN). These oxidants modify LDL and have been strongly linked with the development of atherosclerosis.

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The effects of long-term exposure to extreme space conditions on astronauts were investigated by analyzing hair samples from ten astronauts who had spent six months on the International Space Station (ISS). Two samples were collected before, during and after their stays in the ISS; hereafter, referred to as Preflight, Inflight and Postflight, respectively. The ratios of mitochondrial (mt) to nuclear (n) DNA and mtRNA to nRNA were analyzed via quantitative PCR.

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