An Extended Follow-up Of Stroke Patients For Cognitive Impairment And Neuropsychiatric Disorders: Sydney Stroke Study
Funder
National Health and Medical Research Council
Funding Amount
$321,800.00
Summary
Vascular Dementia (VaD) is the second most common cause of dementia after Alzheimer's disease. In fact, it may be a preventable cause of dementia. Yet it has been relatively neglected by researchers until the last decade, which has seen an upsurge of interest in this disorder. There is no consensus on the criteria for dementia. The profile of early cognitive impairment due to vascular factors is still poorly understood, and the longitudinal course of VaD as defined by modern criteria has not bee ....Vascular Dementia (VaD) is the second most common cause of dementia after Alzheimer's disease. In fact, it may be a preventable cause of dementia. Yet it has been relatively neglected by researchers until the last decade, which has seen an upsurge of interest in this disorder. There is no consensus on the criteria for dementia. The profile of early cognitive impairment due to vascular factors is still poorly understood, and the longitudinal course of VaD as defined by modern criteria has not been studied. There have been few studies of the progressive changes in MRI in patients with cerebrovascular disease. The overlap of VaD and Alzheimer's disease (AD) remains a problem for taxonomists and clinicians. One approach to the study of VaD is to examine a high risk group of subjects longitudinally to determine the early features, the risk factors and progressive changes. With this in mind, we began studying a cohort of stroke patients who are at high risk of VaD, in 1997-1999, and are following them longitudinally. The follow-up is now in its third year, and three neuropsychological assessments and two MRI-MRS scans have been performed. We propose to extend the follow-up to 5 years, with repeat neuropsychiatric, neuropsychological and MRI-MRS investigations, and wherever possible to necropsy, to determine the nature of vascular pathology that underlies cognitive impairment. Our cohort of stroke patients is arguably the most comprehensively assessed such cohorts internationally, and presents an excellent opportunity for a long-term follow-up study.Read moreRead less
THE NATURAL HISTORY OF COGNITIVE IMPAIRMENT AND DEMENTIA IN A STROKE COHORT
Funder
National Health and Medical Research Council
Funding Amount
$290,747.00
Summary
In a current NHMRC-funded study, we have examined 200 stroke patients (and 100 control subjects) at 3 months after a stroke and one year later, and identified those who have impairment in memory and other cognitive functions. We have also studied these subjects in detail from a psychiatric perspective and performed brain scans on them using magentic resonance imaging. We find that many stroke patients have problems with their cognitive functioning which has a major impact on their lives. A large ....In a current NHMRC-funded study, we have examined 200 stroke patients (and 100 control subjects) at 3 months after a stroke and one year later, and identified those who have impairment in memory and other cognitive functions. We have also studied these subjects in detail from a psychiatric perspective and performed brain scans on them using magentic resonance imaging. We find that many stroke patients have problems with their cognitive functioning which has a major impact on their lives. A large number also become depressed. These consequences of stroke are not given sufficient importance by clinicians. The fact that stroke is a common problem in the elderly, and our society is aging, makes this a problem of major public health significance. In the new proposal, we plan to study these subjects up to 3 years with repeat neuropsychiatric assessments and brain scans to investigate the natural history of stroke-related cognitive impairment. We will determine whether further new cases of dementia develop in the period 1-3 years, what happens to the brain lesions picked up on brain scans, and how these deficiencies affect the patients' living status and their longevity. We will be able to determine the factors that lead to a good outcome, and suggest strategies that may be applicable to improve the functioning of these individuals.Read moreRead less
Elucidation Of Immune Mechanisms Underlying HSV Vaccine Development
Funder
National Health and Medical Research Council
Funding Amount
$573,993.00
Summary
HSV-1 and -2 causes genital herpes, cold sores, encephalitis, potential fatal neonatal herpes, keratitis and blindness as well as severe disease in transplant patients. HSV infection also enhances the acquisition of HIV by 2-3 fold. Investigating the mechanism of immune response to HSV infection or components of HSV will assist in understanding immune control of HSV, HSV vaccine development, and assist in reducing in HIV spread.
Identification Of Heterogeneity In Vasodilator Function In Human And Rat Resistance Vessels: Potential Drug Targets?
Funder
National Health and Medical Research Council
Funding Amount
$595,330.00
Summary
The balance between the ways that blood vessels decrease in size (constrict) and increase in size (dilate) determine how blood vessels normally function. There are many differences in the ways that blood vessels control this balance in different parts of the body. Such differences are altered in vascular diseases, such as hypertension and diabetes, which are prevalent in obesity, such that constriction generally outweighs dilation. However, what these differences are and how they occur are not w ....The balance between the ways that blood vessels decrease in size (constrict) and increase in size (dilate) determine how blood vessels normally function. There are many differences in the ways that blood vessels control this balance in different parts of the body. Such differences are altered in vascular diseases, such as hypertension and diabetes, which are prevalent in obesity, such that constriction generally outweighs dilation. However, what these differences are and how they occur are not well understood. While current drugs for treating vascular disease either reduce vessel constriction or increase dilation, they are not specific for individual arteries; a situation that would allow us to control vascular diseases in a very specific manner. Recently, we have described differences between the ways that individual vessels are controlled. These changes relate to differences in the way that different vessels dilate. AIMS - To further understand normal blood vessel function and the changes that occur in blood vessels in cardiovascular disease, with a focus on the ways that blood vessels dilate in normal states and in obesity-related diseases, such as in hypertension and diabetes. - The eventual aim is to identify the specific ways that arteries function, so that artery-specific drug targets can be identified to treat disease-related changes in cardiovascular disease in a very specific manner. EXPECTED OUTCOMES This project will contribute to understanding blood vessel function in health and disease. The expected eventual outcome is the identification of the mechanisms that underlie the function of different arteries in different parts of the body, so that specific individual vessel function can be targeted to treat vascular disease. Additionally, this work will also verify the relevance of the diet-induced obesity animal model, in terms of the characteristics and causes of human obesity and related cardiovascular disease.Read moreRead less
The Role Of Snoring Vibrations In The Pathogenesis Of Early Carotid Artery Atherosclerosis
Funder
National Health and Medical Research Council
Funding Amount
$593,833.00
Summary
Habitual snoring is a very common problem in the adult population, with a prevalence of between 20-40%. Increasingly it is now recognised that snoring may be an independent risk factor for the development of stroke. In this proposal, we will explore the hypothesis that chronic snoring transmits a pressure wave through the tissues of the neck to the carotid artery which may damage the artery wall and subsequently lead to stroke. This may lead to new strategies to treat habitual snoring.
THE VASCULAR CONSEQUENCES OF SNORING AND OBSTRUCTIVE SLEEP APNOEA
Funder
National Health and Medical Research Council
Funding Amount
$476,052.00
Summary
Snoring refers to a condition where the throat narrows significantly during sleep, and allows the soft tissues which surround this part of the airway to vibrate and create the typical snoring noise. Habitual snoring is a very common problem in the adult population, with a prevalence of between 20-40%. More severe forms of snoring are associated with the obstructive sleep apnoea syndrome, which is a condition in which the throat completely blocks behind the tongue and palate during sleep leading ....Snoring refers to a condition where the throat narrows significantly during sleep, and allows the soft tissues which surround this part of the airway to vibrate and create the typical snoring noise. Habitual snoring is a very common problem in the adult population, with a prevalence of between 20-40%. More severe forms of snoring are associated with the obstructive sleep apnoea syndrome, which is a condition in which the throat completely blocks behind the tongue and palate during sleep leading to cessation of breathing for short periods of time. Sleep apnoea is among the commonest chronic disorders of adult males occurring in 5% of men over the age of 45 years. Increasingly, it is now recognised that snoring, without sleep apnoea, may be an independent risk factor for the development of both of these very common and significant medical disorders. However, there have been no studies exploring the mechanisms by which snoring might contribute to the development of stroke and hypertension. In this proposal, we will explore the hypothesis that chronic snoring transmits a pressure wave through the tissues of the neck to the carotid artery which is the main blood supply to the brain. We propose that the chronic vibration of this artery leads to disease such as atherosclerosis and hypertension. Our studies will help to prove that this is a common mechanism whereby both snoring and sleep apnoea may contribute to the development of important vascular diseases. Studies will also establish the prevalence of carotid atherosclerosis in snorers (with and without OSA), and the prevalence of habitual snoring and OSA in patients at risk of developoing completed stroke. The recognition of snoring as an independent risk factor for vascular disease will clearly have important and wide ranging implications for the future management of snoring in the prevention of stroke and hypertension.Read moreRead less
Deciphering Mechanisms Of Liver Allograft Tolerance
Funder
National Health and Medical Research Council
Funding Amount
$520,964.00
Summary
The liver has paradoxical properties: it is the site of effective immune responses to pathogens, but under some circumstances, it is known to induce harmless immune responses. Liver transplants are more readily accepted than other organ grafts in the absence of immunosuppressive drugs but little is known about the mechanisms that prevent an effective response. This proposal aims to unravel these mechanisms. This project will have important implications for transplantation studies.