Cell Biology Of Stress Fractures: Activation Of Remodelling At Sites Of Non-union
Funder
National Health and Medical Research Council
Funding Amount
$493,817.00
Summary
Stress fractures are debilitating injuries. We characterised a model of stress fractures in rat ulnae, learning that they heal by activated remodelling, that key genes are expressed in a temporal pattern, and that part of the fracture remains un-healed, similar to many clinical cases. Now, we will examine cell localisation of important genes necessary for remodelling, and test the efficacy of different growth factors to activate a healing response in the non-healed section of the fracture.
The Role Of Dermal Mast Cells In Limiting The Pathology Associated With Chronic Low-dose UVB Irradiation Of The Skin.
Funder
National Health and Medical Research Council
Funding Amount
$513,945.00
Summary
Australians are subject to high levels of sun exposure , that consequently can lead to skin damage and skin cancer. The specific aims of our reseearch are to investigate the role of skin mast cells in the limitation of skin alterations associated with chronic low-dose ultraviolet B exposure. Understanding the innate mechanisms that protect against excessive skin damage and cancer might aid the development of better treatment modalities in the future.
Early Events In Arteriolar Remodeling: Adaptation To Prolonged Vasoconstriction
Funder
National Health and Medical Research Council
Funding Amount
$415,750.00
Summary
Small arteries, while acutely responding to their environment with changes in diameter to regulate local blood flow and pressure, also undergo structural adaptation or remodelling. These events occur over a range of time-frames and involve both non-genetically and genetically regulated events. Thus a contractile event, while initially decreasing vessel diameter, also activates longer time frame processes which can span from rearrangment of cellular junctions-contacts to overt structural changes ....Small arteries, while acutely responding to their environment with changes in diameter to regulate local blood flow and pressure, also undergo structural adaptation or remodelling. These events occur over a range of time-frames and involve both non-genetically and genetically regulated events. Thus a contractile event, while initially decreasing vessel diameter, also activates longer time frame processes which can span from rearrangment of cellular junctions-contacts to overt structural changes within the vessel wall (for example thickening of the muscle layer). These adaptive processes may enable the forces of contraction to be maintained without continued energy expenditure and damage to the vessel per se. However, they can also contribute to long-term alterations in the control of blood pressure and perhaps contribute to states of hypertension as well as other common vascular diseases. For these studies we will use arterioles, isolated by microsurgical techniques, together with sophisticated computer and video-based approaches. These techniques allow arterioles to be studied under controlled conditions and relevant biochemical measurements performed. We will also use a cell model where cultured cells will be studied after defined periods of mechanical stimulation (for example stretch). Cells will be probed using a novel microscopic technique (atomic force microscopy) which enables the cell membrane to be studied with respect to changes in composition as well as physical characteristics (for example stiffness). The studies are relevant to our understanding of the normal adaptive processes occurring within blood vessels to control blood flow and pressure. The studies are also of direct relevance to our understanding of common vascular disease states including hypertension, complications of diabetes and chronic inflammatory disorders.Read moreRead less
Periodontal Mesenchymal Stem Cells For Periodontal Regeneration
Funder
National Health and Medical Research Council
Funding Amount
$358,000.00
Summary
Dental diseases affecting the gums (periodontal disease) are extremely prevalent in our society. The effects of periodontal disease can be particularly severe as loss of support for the teeth leads to loose teeth and severely compromised masticatory function. If left untreated, the associated pain and loss of function may necessitate extraction of the teeth. We have recently identified cells residing in the periodontal ligament which may be adult stem cells. This project will further characteriz ....Dental diseases affecting the gums (periodontal disease) are extremely prevalent in our society. The effects of periodontal disease can be particularly severe as loss of support for the teeth leads to loose teeth and severely compromised masticatory function. If left untreated, the associated pain and loss of function may necessitate extraction of the teeth. We have recently identified cells residing in the periodontal ligament which may be adult stem cells. This project will further characterize these cells and explore whether they can be used to restore periodontal tissues damaged by periodontal disease.Read moreRead less
Atrial Electrical Remodeling Due To Chronic Stretch: Defining The Substrate For Atrial Fibrillation
Funder
National Health and Medical Research Council
Funding Amount
$428,250.00
Summary
Background: Cardiac failure is a common heart disorder in which the pumping function of the heart is significantly weakened. Mitral regurgitation is a common condition where there is a leakage of blood from the left ventricle (lower heart chamber) back into the left atrium (upper heart chamber) during normal cardiac contraction. This puts a strain on the heart and may cause heart failure. Atrial septal defect is a common form of congenital heart disease which may not be diagnosed until adulthood ....Background: Cardiac failure is a common heart disorder in which the pumping function of the heart is significantly weakened. Mitral regurgitation is a common condition where there is a leakage of blood from the left ventricle (lower heart chamber) back into the left atrium (upper heart chamber) during normal cardiac contraction. This puts a strain on the heart and may cause heart failure. Atrial septal defect is a common form of congenital heart disease which may not be diagnosed until adulthood. There are several forms but the basic problem is leakage of blood from the left atrium into the right atrium .This also puts a strain on the heart and can cause heart failure. All 3 conditions are associated with a significantly increased risk of atrial fibrillation (AF). This abnormal fast irregular cardiac rhythm makes the pumping of the heart inefficient. People with AF may feel short of breath, tired, or develop palpitations. AF is an important cause of stroke and premature death and is the most common heart rhythm disturbance occurring in upto 10% of the over 70 age group. Even after repair of the leaky valve or atrial septal defect there is still a high risk of developing this rhythm. Purpose of the study: This study will try to understand why patients with these conditions are at risk of developing atrial fibrillation, and why this risk might persist after surgical correction when this is possible (mitral regurgitation and atrial septal defect). The study will utilise sophisticated new mapping techniques to gain original insights into the mechanism of this very common and as yet poorly understood heart rhythm disturbance. The study has the potential to determine the cause of atrial fibrillation in these patient groups and as such represent a quantum advance in our understanding of he mechanism of atrial fibrillation. It would be expected to form a foundation on which development of curative and preventative approaches may be based.Read moreRead less
Restoration Of The Nigrostriatal Pathway In The Parkinsonian Brain
Funder
National Health and Medical Research Council
Funding Amount
$299,431.00
Summary
Many obstacles exist for cell transplantation in Parkinson's disease; namely poor restoration of the host brain circuitry due to incorrect graft placement. This results in incomplete motor function and unwanted side effects. Through iterative studies we endeavor to restore this circuitry by placing grafts in the appropriate location and promoting their survival and growth-integrations. This will require: optimizing the donor tissue and exposure of the graft to growth stimulating factors.
Wnt Signaling In Dopaminergic Neuronal Connectivity
Funder
National Health and Medical Research Council
Funding Amount
$564,721.00
Summary
A major obstacle in repairing the injured or diseased brain is inducing axons (nerve cell processes) to make the appropriate connections. This is especially true following cell replacement therapy (CRT) in Parkinson's disease (PD). We will examine the processes inducing axons in the dopamine pathways to grow. We hypothesize that Wnt signaling plays and important role and that therapeutic introduction of Wnt is required to repair the dopamine pathways following CRT in PD.
Pathophysiological Correlates In Smokers And Smoking-related Chronic Obstructive Pulmonary Disease (COPD)
Funder
National Health and Medical Research Council
Funding Amount
$283,500.00
Summary
Smoking-related chronic airway narrowing (COPD) is a common and major illness. Research on the characteristics of the actual pathological process in the airways in smokers and COPD using direct tissue sample is relatively new. Data is currently limited and rather contradictory. In this grant we will recruit a spectrum of smokers and COPD patients typical of those in the Australian community and will be undertaking a detailed analysis of the cellular and some vascular structural changes in the ai ....Smoking-related chronic airway narrowing (COPD) is a common and major illness. Research on the characteristics of the actual pathological process in the airways in smokers and COPD using direct tissue sample is relatively new. Data is currently limited and rather contradictory. In this grant we will recruit a spectrum of smokers and COPD patients typical of those in the Australian community and will be undertaking a detailed analysis of the cellular and some vascular structural changes in the airway wall. Both cellular and vascular changes will be related to the fixed and reversible component of airway obstruction. Reversible changes with smoking cessation will be studied. A very novel feature will be a preliminary assessment of the utility of proteomics for assessment of airway pathology.Read moreRead less
Improving Immunotherapy By Vascular Targeting And Barrier Alteration
Funder
National Health and Medical Research Council
Funding Amount
$526,878.00
Summary
Tumors grow in part because they escape destruction by the immune system. New blood vessels grow inside tumors by a process called angiogenesis, which then stops cancer-fighting cells in their tracks. We hypothesise that breaking down the blood-tumor barrier will open tumors for attack by the cancer-fighting immune system. This proposal continues our work on reversal of angiogenesis in the context of immunotherapy. We expect these findings to lead to highly effective anti-tumor therapies.
Anti-atherosclerotic Effects Of Angiotensin Fragments & Non-AT1 Receptors: Validation As Innovative Therapeutic Targets
Funder
National Health and Medical Research Council
Funding Amount
$512,065.00
Summary
In Australia the largest cause of death is coronary heart disease (CHD) leading to heart attacks or stroke and claiming a staggering 28,000 lives a year. Atherosclerosis is one of the leading causes of cardiovascular disease, with diseased vessels not able to fully dilate and the plaque that has built up inside these vessels impeding blood flow and possibly rupturing, resulting in heart attacks and stroke. One of the major players in the development and progression of atherosclerosis is the horm ....In Australia the largest cause of death is coronary heart disease (CHD) leading to heart attacks or stroke and claiming a staggering 28,000 lives a year. Atherosclerosis is one of the leading causes of cardiovascular disease, with diseased vessels not able to fully dilate and the plaque that has built up inside these vessels impeding blood flow and possibly rupturing, resulting in heart attacks and stroke. One of the major players in the development and progression of atherosclerosis is the hormone, angiotensin II. Angiotensin II has been found to trigger many factors that cause thickening of the vessel wall, inflammation and imbalances in vasodilator capacity (e.g. oxidative stress and endothelial dysfunction), all of which contribute to atherosclerosis. Clinical trials with drugs that inhibit the formation of angiotensin II (ACE inhibitors), or block the action of angiotensin II (angiotensin receptor antagonists), have demonstrated a significant decrease in mortality in patients with high risk for cardiovascular disease. However their mechanism(s) of action are not fully understood as the circulating levels of shorter fragments of angiotensin II (such as Ang IV and Ang (1-7)) are raised in the blood when these drugs are used and may contribute to the protective effects of these drugs. Importantly, we have found that both Ang IV and Ang (1-7) have protective effects in atherosclerotic blood vessels. Therefore, we hypothesise that fragments of angiotensin II (such as Ang IV and others) exert anti-atherogenic effects via distinct binding sites that oppose the effects caused by angiotensin II, and that these may be partly responsible for the cardio-protective effects of the ACE inhibitors and angiotensin receptor antagonists. Thus, information gained in our study will be useful in directing future prescription practices in clinical management of CHD and stroke, and for designing new therapeutic compounds for the management of atherosclerosis.Read moreRead less