Is EphA4 The Major Molecular Regulator Of Axonal Regeneration?
Funder
National Health and Medical Research Council
Funding Amount
$491,000.00
Summary
Spinal cord injury affects a substantial number of Australians each year. Around half the number of spinal cord injury cases result in quadriplegia, with loss of function to a varying degree in the upper as well as the lower limbs. The limited degree of repair of spinal axons following injury means that such paralysis is usually permanent. Although the inability to walk is a serious issue, the limited function of the arms and hands results in a loss of independence which is a major factor contri ....Spinal cord injury affects a substantial number of Australians each year. Around half the number of spinal cord injury cases result in quadriplegia, with loss of function to a varying degree in the upper as well as the lower limbs. The limited degree of repair of spinal axons following injury means that such paralysis is usually permanent. Although the inability to walk is a serious issue, the limited function of the arms and hands results in a loss of independence which is a major factor contribuing to the enormous personal, financial, and community costs of this problem, estimated to cost the Australian community $200 million a year. In recent years advanced anatomical and molecular approaches to the problem of repair of the central nervous system have provided great insights into the neuronal and glial reactions to neural damage that appear to govern the success or failure of neural regeneration. Our preliminary data indicate that a receptor tyrosine kinase, EphA4, which is important for axonal pathfinding in the developing nervous system, is a potent inhibitor of neural regeneration following spinal cord injury. In this project we will determine the mechanisms by which EphA4 exerts its inhibitory effects, and examine the effect of neutralizing EphA4 signalling on neural regeneration. Success in achieving this result will lead to the development of a therapeutic intervention that we will test in mouse models.Read moreRead less
The Use Of Soluble Antagonists Of EphA4 In Spinal Cord Injuries
Funder
National Health and Medical Research Council
Funding Amount
$622,361.00
Summary
Permanent and limited recovery of function following spinal cord injury is a direct result of the lack of nerve regrowth through the injury. Our preliminary data suggest that antagonising the effects of EphA4, a protein involved in brain development, leads to substantial functional recovery simultaneous with nerve regrowth. In addition to designing new, more effective blockers of EphA4, we will study the signalling pathways that EphA4 activates to inhibit nerve regrowth.
Control Of Mastication By Periodontal Mechanoreceptors In Man
Funder
National Health and Medical Research Council
Funding Amount
$169,990.00
Summary
Despite the importance in chewing and speech, very little is known regarding the fine control of jaw muscles. A thorough understanding of the control of the jaw muscles is at the base of improved diagnosis and treatment of many chewing disorders. For example: We still do not understand the causes of the jaw muscle-joint pain disorder (temporomandibular dysfunction) which accounts for about 5 % of total dental patients. The current treatments, including pain killers, night plates and massage cure ....Despite the importance in chewing and speech, very little is known regarding the fine control of jaw muscles. A thorough understanding of the control of the jaw muscles is at the base of improved diagnosis and treatment of many chewing disorders. For example: We still do not understand the causes of the jaw muscle-joint pain disorder (temporomandibular dysfunction) which accounts for about 5 % of total dental patients. The current treatments, including pain killers, night plates and massage cure only about half of all patients. Improved diagnosis and treatment techniques require more precise elaboration of the neural and muscular mechanisms of chewing. Why do the chewing forces in toothless individuals, despite well fitting dentures, fall to about 20 % of the value in teethed individuals? Do jaw muscles in these subjects weaken because they get less feedback from the receptors around the teeth? How does the chewing force automatically adjust to overcome sudden or gradual changes in the characteristics of foodstuff? Although bite to bite changes in the chewing force is observed in subjects with natural teeth, no such changes occur in toothless subjects or subjects chewing with implanted bridges. How do the receptors adjust the activation of jaw muscles so that bite force is applied in the right direction and right amount at each bite? The aim of this study is to define the importance of the periodontal mechanoreceptors (tiny nerve cells that are situated between the roots of the teeth and the jaw bone that signal bite force to the brain) in the control of jaw muscles. This study will, therefore, illustrate the importance of keeping the teeth and gums healthy for the development of strong, smooth and well-controlled chewing forces, and potentially create opportunities to improve chewing (and thereby quality of life) in toothless individuals or those experiencing other difficulties in chewing.Read moreRead less
Exertional Dyspnoea With Increased Filling Pressure - Mechanisms And Treatment Strategies
Funder
National Health and Medical Research Council
Funding Amount
$387,793.00
Summary
Patients with early heart disease often present with shortness of breath with exercise, as myocardial reserve at that stage is usually sufficient to maintain normal function at rest . Indeed, much myocardial dysfunction may originate from the modern lifestyle, including inactivity, obesity, the metabolic syndrome and type II diabetes. The potential benefits of making a definitive early diagnosis are large, because it seems more likely that an impact can be made on the disease process (and theref ....Patients with early heart disease often present with shortness of breath with exercise, as myocardial reserve at that stage is usually sufficient to maintain normal function at rest . Indeed, much myocardial dysfunction may originate from the modern lifestyle, including inactivity, obesity, the metabolic syndrome and type II diabetes. The potential benefits of making a definitive early diagnosis are large, because it seems more likely that an impact can be made on the disease process (and therefore, outcome) than with late stage disease. Current treatment strategies are expensive and because they are directed at end-organ damage (heart failure, heart attacks etc), rather ineffective. This multispecialty, multidisciplinary group will undertake a series of unique studies aimed at identifying early cardiovascular disease. The strategy will involve detection of abnormal filling behaviour at stress echocardiography, with randomization into longterm and short-term trials to examine various therapeutic strategies. Sensitive new cardiovascular imaging techniques will be used to detect preclinical abnormalities in the structure and function of the heart and vasculature, facilitating a mechanistic understanding of the process of increasing filling pressure with exercise.Read moreRead less
The Effect Of CPAP On Erectile And Endothelial Dysfunction In Impotent Men With Obstructive Sleep Apnea
Funder
National Health and Medical Research Council
Funding Amount
$609,559.00
Summary
Erectile dysfunction is common in men with obstructive sleep apnea, due to vascular damage, which leads to heart attack. CPAP is the preferred treatment for patients with OSA because of its well-proven ability to decrease sleepiness and improve blood pressure control. This study will establish if CPAP can also improve erectile and vascular endothelial dysfunction. These results will shed light on the mechanisms that underpin the relationship between OSA and Erectile Dysfunction.
The Australian Parkinson's Project - Uncovering Genetic Risk Factors For Sporadic PD
Funder
National Health and Medical Research Council
Funding Amount
$768,546.00
Summary
Parkinson s disease (PD) is a progressively disabling movement disorder afflicting many elderly Australians. It is caused by the degeneration of specific nerve cells in the brain that produce certain chemicals and patients suffer from an inability to move fluently (or ultimately at all). At present we do not know what triggers this neurodegeneration, but it is believed that complex interactions between inherited (genetic) and environmental factors contribute significantly to the phenomenon. This ....Parkinson s disease (PD) is a progressively disabling movement disorder afflicting many elderly Australians. It is caused by the degeneration of specific nerve cells in the brain that produce certain chemicals and patients suffer from an inability to move fluently (or ultimately at all). At present we do not know what triggers this neurodegeneration, but it is believed that complex interactions between inherited (genetic) and environmental factors contribute significantly to the phenomenon. This project aims to learn more about these complex interactions and their association with PD. People with PD and unaffected individuals will be recruited from throughout Australia and we will look for specific combinations of genetic, environmental and lifestyle factors that either increase or decrease an individual's risk for PD. This research will identify the most common dominant genetic and environmental influences for PD in Australia, enabling scientists to focus on the most relevant biological pathways to target therapeutically.Read moreRead less
Efficacy And Mechanisms Of Exercise Training In Diastolic Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$385,250.00
Summary
Heart failure is modern epidemic which presents a significant public health burden, due to a high mortality, frequent hospital admissions and impaired functional capacity. Although the typical heart failure patient presents with a reduced contractile function, many patients have typical heart failure symptoms but with normal contraction. The problem in these patients seems to relate to the heart's ability to fill with blood, and this entity is known as diastolic heart failure (DHF). This syndrom ....Heart failure is modern epidemic which presents a significant public health burden, due to a high mortality, frequent hospital admissions and impaired functional capacity. Although the typical heart failure patient presents with a reduced contractile function, many patients have typical heart failure symptoms but with normal contraction. The problem in these patients seems to relate to the heart's ability to fill with blood, and this entity is known as diastolic heart failure (DHF). This syndrome is most frequently due to ischemic or hypertensive heart disease, and most commonly occurs in the elderly. The optimal management of DHF is not well defined, although some drug trials are currently in progress. A number of studies have shown exercise training to improve functional capacity by 15-20% in typical heart failure. However, training has not so far been trialled in DHF. In this multicenter, multi-disciplinary study, we will study a training and control group to determine whether exercise capacity and DHF symptoms are responsive to exercise training. This work will teach us about the optimum exercise prescription, in terms of the duration and nature of training, as well as the safety and effectiveness of exercise training. By using a number of sensitive measurements of heart and vessel function (in which our group has special expertise), we will identify whether exercise training exerts its effect through improvement in vascular function and myocardial properties. If successful, the clinical implications of this study are that; 1. Exercise training will be adopted to improve functional capacity and symptoms of DHF 2. The merits of aerobic and strength training will be identified in DHF 3. Abnormal blood vessel function will be identified as a major and reversible contributor to DHFRead moreRead less
Understanding Local And Regional Determinants Of EDHF And NO Dysfunction In Resistance Arteries In Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$771,295.00
Summary
Diabetes is a serious and increasing health burden worldwide. Most of the sickness and death associated is due to complications arising in the blood vessels. The inner lining of blood vessels in small arteries uses several different mechanisms to ensure proper blood flow, and in diabetes these are impaired. This study will reveal the cellular mechanisms involved and identify pathways for therapeutic intervention to alleviate the debilitating effects of small artery disease.