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
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.
Local Sleep In The Awake Brain: An Underlying Cause Of Neurobehavioural Deficits In Sleep Apnea?
Funder
National Health and Medical Research Council
Funding Amount
$582,330.00
Summary
Obstructive sleep apnea (OSA) is a common sleep disorder which significantly impacts daytime functioning leading to excessive sleepiness, and problems with attention and thinking. Currently, the causes for cognitive impairment in OSA (including attentional lapses and performance deficits) are poorly understood. In the awake state, groups of neurons can briefly go “offline” as they do in sleep. These periods of “local sleep” may explain impaired task performance in OSA.
Vascular And Neurogenic Determinants Of Hypertension In Chronic Kidney Disease
Funder
National Health and Medical Research Council
Funding Amount
$508,142.00
Summary
You are as old as your arteries, and people with kidney disease have arteries that age fast. They also have overactive sympathetic nerves, and it is not clear if the blood vessels or nerves are responsible for the high blood pressure that puts strain on the heart and other organs of these patients. We will use an animal model to determine if therapy for hypertension reduces the stiffness of blood vessels or elevated nerve activity. Our results will enable better treatments for kidney failure.
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
Analysis Of Viral And Cellular Gene Expression During Human Cytomegalovirus Latent Infection Of Hematopoietic Cells
Funder
National Health and Medical Research Council
Funding Amount
$407,545.00
Summary
Human cytomegalovirus (HCMV) is a herpesvirus which infects a majority of the population. HCMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Transplant recipients such as bone marrow, kidney and heart transplant patients are particularly at risk of developing HCMV disease. Like other herpesviruses, after initial infection HCMV can establish a life-long latent infection. During latency, the virus remains dormant in the human body a ....Human cytomegalovirus (HCMV) is a herpesvirus which infects a majority of the population. HCMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Transplant recipients such as bone marrow, kidney and heart transplant patients are particularly at risk of developing HCMV disease. Like other herpesviruses, after initial infection HCMV can establish a life-long latent infection. During latency, the virus remains dormant in the human body and no infectious virus is made. However, when conditions are right the virus can awaken (ie reactivate) from its latent state, producing new infectious virus and disease. It is in immunosuppressed individuals such as transplant patients that viral latency and reactivation are of most medical concern, yet viral latency remains very poorly understood. This project has three major components. Firstly, we aim to continue studies which are defining what viral genes are active (ie expressed) during latent infection. Identification of these genes and determination of how they function may have profound implications to our understanding of latency. Secondly, we will examine how human cells are affected when they become latently infected. A new and exciting technology called DNA microarray now makes it possible to examine the expression of many thousands of genes in a single experiment. For the first time, we will be able to determine how the cell changes during latency and reactivation. The study of viral and cellular gene expression during latency may contribute to the development of drugs which interfere with the viruses ability to become latent or reactivate. Thirdly, we have preliminary results which suggest that latent HCMV may actively avoid detection by the immune system. In this project we also aim to determine the mechanism by which the virus interferes with the expression of molecules which are an essential component of our immune system.Read moreRead less
A-Prof Wheatley is a respiratory and sleep disorders physician investigating the pathogenesis, health consequences and management of sleep breathing disorders, including sleep apnoea and snoring.