A Study Of The Molecular Epidemiology And Virulence Determinants Of Enterovirus 71 Strains From The Asia-Pacific Region
Funder
National Health and Medical Research Council
Funding Amount
$286,325.00
Summary
In this study, we aim to understand the reasons for the emergence of epidemics of severe neurological disease due to enterovirus 71 (EV71) in young children of the Asia-Pacific region since 1997, and to develop strategies for disease prevention. EV71 is a human enterovirus closely related to the polioviruses. Most infections with EV71 are trivial, however, they may occasionally result in severe disease, including brainstem encephalitis with a high mortality and acute flaccid paralysis similar to ....In this study, we aim to understand the reasons for the emergence of epidemics of severe neurological disease due to enterovirus 71 (EV71) in young children of the Asia-Pacific region since 1997, and to develop strategies for disease prevention. EV71 is a human enterovirus closely related to the polioviruses. Most infections with EV71 are trivial, however, they may occasionally result in severe disease, including brainstem encephalitis with a high mortality and acute flaccid paralysis similar to poliomyelitis. There has been a large increase in EV71 epidemic activity throughout the Asia-Pacific region since 1997, including a large epidemic in Perth, Western Australia in 1999. These epidemics have resulted in many deaths and cases of severe neurological disability. In view of the severity of EV71 neurological disease and the lack of effective treatments, our research effort needs to focus on prevention through public health surveillance and vaccine development. The major aims of our study are two-fold: 1. To study the origin and evolution of EV71 in the Asia-Pacific region using molecular techniques and to use this information to implement surveillance in Australia and Southeast Asia. It is anticipated that improved surveillance will provide early warning of impending epidemics. 2. To understand the molecular basis of virulence of EV71, with emphasis on the ability of virus to cause severe disease of the central nervous system. This study will have two goals: a. To identify the human cellular receptor of EV71. The ultimate goal of this research will be the development of a small animal model of EV71 encephalitis by constructing a transgenic mouse expressing the human cellular receptor for EV71. b. To construct an infectious cDNA clone of EV71 and to develop genetically defined attenuated strains by mutagenesis of the infectious clone. Mutant strains of EV71 will be tested for replication and virulence in newborn mice and in human neuroblastoma cells.Read moreRead less
A Study To Investigate Alternative Regimens For Pneumococcal Vaccination Of Infants In A Developing Country
Funder
National Health and Medical Research Council
Funding Amount
$1,622,210.00
Summary
Streptococcus pneumoniae (Pnc) is the leading vaccine preventable cause of serious infection in infants. The current Pnc conjugate vaccine is very expensive (approximately USD $200-infant) so it is unlikely to be affordable for most developing countries. Moreover, as health care access in developing countries may be episodic and unreliable, many children do not receive either complete or timely vaccine courses. Therefore, it is important to investigate affordable and flexible ways to deliver thi ....Streptococcus pneumoniae (Pnc) is the leading vaccine preventable cause of serious infection in infants. The current Pnc conjugate vaccine is very expensive (approximately USD $200-infant) so it is unlikely to be affordable for most developing countries. Moreover, as health care access in developing countries may be episodic and unreliable, many children do not receive either complete or timely vaccine courses. Therefore, it is important to investigate affordable and flexible ways to deliver this vaccine, which are safe and effective. A recent WHO-GAVI meeting to address impediments to the introduction of these vaccines in developing countries recognized the need to evaluate other regimens of Pnc conjugate vaccine as an important research priority. This study has been deliberately formulated with that need in mind. The site for this research is Fiji. Although health services are good, Pnc disease, particularly pneumonia, remains the commonest cause of childhood morbidity and mortality. Fiji has good vaccine coverage and was the first Pacific country to introduce Hib vaccine. The arrival of the new, expensive Pnc conjugate vaccine presents a dilemma for Fiji and many similar countries. The expense of this vaccine would consume a large portion of the health budget. This study has two components: 1. A Phase 2 immunogenicity study (involving 750 infants) to evaluate regimens using reduced numbers of doses of Pnc conjugate vaccine, and using timing of dosing and combinations with the Pnc polysaccharide (PS) vaccine that may be more suited to the epidemiology of Pnc disease in developing countries. 2. An epidemiological study will measure the burden of invasive Pnc disease and pneumonia in Fiji. This will be part of a global effort to address these issues, and will be used to develop rapid assessment tools for these diseases in developing countries. We will seek cofounding for this component.Read moreRead less
Mechanisms Guiding Pathfinding And Positioning Of Cortical Interneurons
Funder
National Health and Medical Research Council
Funding Amount
$621,606.00
Summary
Brain disorders place an economic and social burden on Australia and the personal costs of these illnesses are immeasurable. Several brain abnormalities are caused from the failure of neurons to position themselves in the correct location when the brain develops. Our study aims to discover how neurons move and what factors influence this process. It provides an understanding of normal brain development, as well as providing insight into what may go wrong in the formation of brain diseases.
Understanding How Language And Reading Problems Develop: A Population-based Longitudinal Study From Infancy To Age 7
Funder
National Health and Medical Research Council
Funding Amount
$667,507.00
Summary
Early language and reading problems are common and therefore significant public health problems. They are disabling and have life-long implications for oral and written communication skills, social and emotional well-being, cognition, behaviour, academic achievement and employment. This study will address the following three problems: 1. To date no study has documented how language and reading problems develop from infancy (8 months) through to school age (7 years). 2. Little is known about risk ....Early language and reading problems are common and therefore significant public health problems. They are disabling and have life-long implications for oral and written communication skills, social and emotional well-being, cognition, behaviour, academic achievement and employment. This study will address the following three problems: 1. To date no study has documented how language and reading problems develop from infancy (8 months) through to school age (7 years). 2. Little is known about risk factors, identified early in infancy and childhood, that can be reliably used to predict language and reading problems later in childhood. 3. The relationships between language difficulties and reading problems are poorly understood. Therefore, we currently have no satisfactory methods for reliably detecting which children at much younger ages are at risk of later language disorders or reading problems. Without this information it is impossible to develop effective prevention and early intervention programs. These programs are critical if we are to: a) Prevent language and reading problems from occurring, thereby reducing the prevalence of the problem b) Intervene early in childhood, thereby reducing in the longer term the burden and cost associated with language and reading problems. The proposed study builds on an existing substantial investment by the NHMRC in the Early Language in Victoria Study (ELVS). It will provide a world-first description of the evolution of language difficulties and reading problems from infancy through to school age within a single population cohort.Read moreRead less
The Role Of Rnd Genes During Cortical Neurogenesis And Cell Migration
Funder
National Health and Medical Research Council
Funding Amount
$410,384.00
Summary
In order for the brain to function properly, tens of billions of neurons within it first have to be born, then find their proper location before connecting with other neurons in a highly ordered fashion. Failure of these key processes heavily impacts on subsequent brain function, and have been shown to underlie several disorders including epilepsy. This study will investigate how members of the Rnd gene family control cell production and positioning within the developing brain.
Antigen Selection In The MHC-restricted Cellular Immune Response
Funder
National Health and Medical Research Council
Funding Amount
$175,570.00
Summary
The body's white cells eliminate microorganisms through the actions of immune lymphocytes and other cells which conspire to kill and neutralise these unwanted guests. When microorganisms hide inside the cells of the body they are still detected by a set of T lymphocytes which have specific receptors for scrutinising the surface of cells for any changes which might signal an intracellular infection. The immune system is ever vigilant in its search for signs of infection which are generally appare ....The body's white cells eliminate microorganisms through the actions of immune lymphocytes and other cells which conspire to kill and neutralise these unwanted guests. When microorganisms hide inside the cells of the body they are still detected by a set of T lymphocytes which have specific receptors for scrutinising the surface of cells for any changes which might signal an intracellular infection. The immune system is ever vigilant in its search for signs of infection which are generally apparent when molecules called antigens are released by microorganisms and captured by the body's cells. This activates lymphocytes resulting in an immune response capable of eliminating the microorganisms. Scrutiny of the body's cells by lymphocytes occurs continuously even when there is no infection present in the body. Following infection of a cell, microbial antigens reveal the infection by their appearance on the cell surface where they are detected by the immune system's lymphocytes. This occurs through a mechanism called antigen presentation. During antigen presentation the proteins inside the cell, including those of any invading microorganism, are first degraded into shorter molecules called peptides. This event is called antigen processing. A fraction of the peptides created by antigen processing are captured by specialised receptors present on all cells. These receptors are called HLA or histocompatibility molecules. This project examines the molecular events which mediate the capture of peptide antigens by HLA molecules. The main focus is on those peptide antigens which elicit killer T cell responses by the immune system. A knowledge of how these peptides are selected for presentation and how they are captured and carried to the cell surface is fundamental to understanding immune responses to microorganisms, tumours, allergens, transplants and self tissues as in autoimmunity. Therefore the study is of great general relevance.Read moreRead less
The Role Of GRHL-3, A Mammalian Homologue Of Drosophila Grainyhead, In Neural Tube Development
Funder
National Health and Medical Research Council
Funding Amount
$496,500.00
Summary
Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first ....Spina bifida and anencephaly are two common human congenital malformations that form part of a wide spectrum of mutations known collectively as neural tube defects (NTDs). Patients with the most severe form of spina bifida have a failure of the vertebral column and skin to close over the spinal cord and therefore suffer from limb paralysis and marked bladder and bowel dysfunction. Infants with anencephaly have an open cranial vault and failure of normal brain development and die within the first few hours of life. These abnormalities occur frequently (1-1000 live births) and are a direct result of failure of the neural tube to close during embryogenesis. NTDs are influenced by both environmental and genetic factors. The best characterised environmental factor is the dietary supplement folate, which when administered before conception results in a reduction in the incidence of spina bifida. The genetic complexity is evidenced by the array of mouse genetic mutations that give rise to NTDs. One of these mouse mutations, known as Curly tail (ct), has served as the major animal model of human NTDs. This is because the ct mice are resistant to folate administration (like most of the cases of spina bifida currently seen in patients) and because the mice seem to have normal development in virtually all other organ systems. Ironically, the genetic mutation that causes the curly tail phenotype has remained undiscovered for over 50 years. We have now identified the gene mutated in the curly tail mice. This gene is highly conserved in humans suggesting that it will play a similar role in neural tube development in man. The gene, known as GRHL-3, is a descendant of a fly gene critical for development of the nervous system in that organism. The studies we propose here will examine the developmental pathways involved in normal neural tube closure in mice and humans and will impact on our understanding of these devastating congenital malformations.Read moreRead less
Defining Genetic And Epigenetic Variation During Early Development
Funder
National Health and Medical Research Council
Funding Amount
$996,075.00
Summary
We all began life with a set of genes inherited from our parents. However, it's now known that from the time we were in the womb onwards that genes can be turned off and on by the environment or even completely lost or gained. Even what your mother ate or how she behaved while she was pregnant could have influenced your future health. Because people are so different, we are studying the subtle differences between twins to tease out the factors that may influence our genes and our health.
Identification Of Novel Mechanisms Governing Stage-specific Regulation Of The Human Globin Genes
Funder
National Health and Medical Research Council
Funding Amount
$481,826.00
Summary
Hemoglobin is the major protein in red blood cells and is essential for the transport of oxygen from the lungs to the tissues. The disorders of hemoglobin production are the commonest genetic diseases worldwide. These diseases can be markedly improved with elevation of the form of hemoglobin produced by the developing embryo, fetal hemoglobin. We have identified key factors important for fetal gene expression. Our goal is to translate these findings into therapies for the hemoglobin disorders.
Migration And Differentiation Of Enteric Neuron Precursors
Funder
National Health and Medical Research Council
Funding Amount
$385,116.00
Summary
There are many millions of nerve cells within the wall of the intestine, and they control many intestinal functions, including motility. During development, these nerve cells arise from cells which migrate away from the developing brain and first enter the stomach. The migratory cells are called neural crest cells. After entering the stomach, neural crest cells migrate within the wall of the gastrointestinal tract, until they reach the far (anal) end. In embryonic mice, this colonisation of the ....There are many millions of nerve cells within the wall of the intestine, and they control many intestinal functions, including motility. During development, these nerve cells arise from cells which migrate away from the developing brain and first enter the stomach. The migratory cells are called neural crest cells. After entering the stomach, neural crest cells migrate within the wall of the gastrointestinal tract, until they reach the far (anal) end. In embryonic mice, this colonisation of the entire small and large intestines by neural crest cells takes over 4 days, and in humans the process probably takes at least one week. It is essential that the neural crest cells colonise the entire gastrointestinal tract, since regions of intestine lacking neural crest cells (and hence nerve cells) cannot function and intestinal contents build up in front of the region lacking nerve cells. This condition is found in some babies (Hirschsprung's disease), and it can only be treated by surgically removing the region lacking nerve cells. It is therefore essential that migratory neural crest cells colonise the entire gastrointestinal tract. Currently, little is known about the mechanisms controlling the migration of neural crest cells, and whether a) particular molecules within the gut wall are important for migration, and-or b) the migratory behaviour of the neural crest cells is regulated mostly by the neural crest cells themselves. In this study we will take time-lapse images of neural crest cells migrating through the gut of embryonic mice to identify the factors that are important for the migration. After the neural crest cells have colonised the entire intestine, they develop into different types of nerve cells. We will also examine some of the factors affecting the development of different types of nerve cells.Read moreRead less