The Extinction Of Conditioned Fear And Its Implications For Cue Exposure Therapy
Funder
National Health and Medical Research Council
Funding Amount
$322,430.00
Summary
This project studies extinction of Pavlovian conditioned fear reactions in rats. Extinction of these reactions is an animal model for exposure therapy used in the treatment of anxiety disorders in people. In exposure therapy, the patient, aided by the clinician, confronts trauma-related cues in the absence of any overt danger. The intention of this therapy is to reduce the ability of the trauma-related cues to provoke the fear reactions that are undermining the patient's quality of life. In Pavl ....This project studies extinction of Pavlovian conditioned fear reactions in rats. Extinction of these reactions is an animal model for exposure therapy used in the treatment of anxiety disorders in people. In exposure therapy, the patient, aided by the clinician, confronts trauma-related cues in the absence of any overt danger. The intention of this therapy is to reduce the ability of the trauma-related cues to provoke the fear reactions that are undermining the patient's quality of life. In Pavlovian conditioning, subjects (typically rats) are exposed to a signaling relation between an initially neutral stimulus (e.g., a noise) and a feared outcome (e.g., foot shock). When later repeatedly exposed to the initially neutral but now feared stimulus (the noise) in the absence of the feared outcome, the fear reactions it acquired progressively decline until eventually it fails to elicit any such reactions. The fear reactions are said to have been extinguished. There has been significant progress in understanding the psychological processes and neural mechanisms underlying the acquisition of fear reactions, but much less is known about the processes and mechanisms underlying the extinction of these reactions. The project has two general objectives. The first is to determine the conditions of extinction training that promote long-term loss of fear reactions. The second objective is to determine how the brain controls this extinction of learned fear. Achieving these aims will be significant for two reasons. First, it will contribute to understanding the mechanisms by which animals (including people) learn to adjust their behaviour to bring it into line with the current relations that exist between events in the world. Second, it will provide important information about how such adjustment is facilitated or impaired across extinction training and, thereby, contribute towards understanding both the successes and failures of cue exposure therapy for fear-related disorders.Read moreRead less
Cognitive Enhancement In Schizophrenia Via Selective Oestrogen Receptor Modulator.
Funder
National Health and Medical Research Council
Funding Amount
$396,380.00
Summary
Cognitive dysfunction in schizophrenia is resistant to treatment and related to poor community functioning and quality of life. In spite of the widely appreciated magnitude of the problem, there is still a critical gap in our knowledge concerning treatments to reverse these cognitive deficits. The proposed research is significant because it will clarify the role of hormones and genes in relation to cognitive deficits in schizophrenia and it may help patients improve their level of functioning.
A NOVEL MOUSE MODEL TO INVESTIGATE THE MECHANISMS OF VIRUS-INDUCED ARTHRITIS
Funder
National Health and Medical Research Council
Funding Amount
$336,000.00
Summary
We have developed a novel animal model by which to study arthritic disease caused by insect-transmitted viruses known as arboviruses. The existence of this model and novel reagents provides an excellent opportunity to further explore the basic mechanisms of infectious disease in a complete functioning animal, rather than specific cultured cells. The study will use modern approaches in molecular and cellular biology to achieve this goal. The production by our immune systems of soluble mediators ( ....We have developed a novel animal model by which to study arthritic disease caused by insect-transmitted viruses known as arboviruses. The existence of this model and novel reagents provides an excellent opportunity to further explore the basic mechanisms of infectious disease in a complete functioning animal, rather than specific cultured cells. The study will use modern approaches in molecular and cellular biology to achieve this goal. The production by our immune systems of soluble mediators (cytokines-chemokines) and antibodies is an overwhelming positive aspect of our physiological response to infection by microbes. Protection from disease by these immune compounds can happen naturally, or the body's ability to produce these factors can be exploited to our benefit via the administration of vaccines. However, these factors can also be detrimental to the host contributing to severe disease. For instance, work performed almost 40 years ago showed for the first time that under particular conditions, antibodies against viruses can enhance infection, instead of inhibiting infection as normally seen. In the intervening years work by scientists all over the world has associated antibody-dependent enhancement (ADE) of infection to many types of viruses; ADE is even thought to be a risk factor to serious disease with dengue virus, and has been shown in vitro for the AIDS virus and Ebola virus. We have recently discovered a molecular mechanism which explains how antibody enhances viral infection in vitro. In studies on immune cells infected with Ross River Virus (RRV) we found that infection helped by antibody resulted in the specific disruption to the production of cellular chemicals which are toxic to viruses. Are these mechanisms of antibody-enhanced infection also found in animals? Will such mode of infection cause enhanced disease and tissue pathology (arthritis) in animals?Read moreRead less
Impact Of DTP Schedules On The Immunogenicity Of 2 Doses Of 13v-PCV Followed By An Early Booster
Funder
National Health and Medical Research Council
Funding Amount
$2,651,687.00
Summary
This project aims to come up with a vaccination schedule to make pneumococcal vaccines more effective and affordable for Fiji and other developing countries. We will evaluate schedules involving a 2 dose primary series in early infancy with a booster at 9 months of age. We will compare the immune responses to 3 different primary series and 2 booster options. The results of this project will be used to provide advice, at global and country levels, regarding introduction of pneumococcal vaccines.
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
Molecular Mechanisms Of Varicella Zoster Virus Interactions With Key Target Cells
Funder
National Health and Medical Research Council
Funding Amount
$421,650.00
Summary
Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chickenpox (varicella) predominantly in childhood and shingles (herpes zoster) in middle to old age people. Whilst VZV usually causes relatively mild disease in healthy individuals, VZV still causes significant morbidity in children and adults. VZV causes life-threatening disease in immunocompromised individuals such as patients who are elderly or have HIV disease . Herpes zoster affects many eder ....Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chickenpox (varicella) predominantly in childhood and shingles (herpes zoster) in middle to old age people. Whilst VZV usually causes relatively mild disease in healthy individuals, VZV still causes significant morbidity in children and adults. VZV causes life-threatening disease in immunocompromised individuals such as patients who are elderly or have HIV disease . Herpes zoster affects many ederly individuals and a major complication is prolonged severe pain or post-herpetic neuralgia (PHN), both severely debilitating and which often requires follow-up medical care for months or years after the initial attack. Despite its significant impact on the community, little is known about the molecular details of how this virus functions. This project aims to improve our understanding of how VZV infection affects specialised human cells in order to make further advances in antiviral therapies as well improve vaccine design for the treatment or prevention of VZV disease and the crippling complication of PHN. This project has four components: (1) We will continue studies which have shown that VZV may actively avoid detection by the immune system. We aim to identify the mechanism and viral genes responsible for interfering with the expression of molecules which are essential for our immune system. (2) We will determine whether VZV infection of specialised immune cells (called dendritic cells) will affect their ability to function and interact with other immune cells (called T cells). (3) We will examine how VZV interacts in human nerve cells (neurons) and whether infected neurons undergo specially programmed cell death (apoptosis). (4) We will examine how different human cells change when they are infected with VZV. A new and exciting technology called DNA microarray now makes it possible to examine the expression of many thousands of genes in one experiment.Read moreRead less