The Embryological And Molecular Basis Of Zic2 Involvement In Holoprosencephaly
Funder
National Health and Medical Research Council
Funding Amount
$624,145.00
Summary
The brain is the most complex organ in the human body and diseases or disorders of the brain can become evident at any stage of life. Generally such problems have profound consequnces for the affected individuals and their families. One of the most common problems of brain development that is evident either at birth or within the first years of life is called holoprosencephaly (HPE). This condition affects the midline of the brain and the face and can lead to delay in mental, motor and language ....The brain is the most complex organ in the human body and diseases or disorders of the brain can become evident at any stage of life. Generally such problems have profound consequnces for the affected individuals and their families. One of the most common problems of brain development that is evident either at birth or within the first years of life is called holoprosencephaly (HPE). This condition affects the midline of the brain and the face and can lead to delay in mental, motor and language development, seizures, and obvious facial abnormalities. In its most severe form only one eye develops in the middle of the face, a condition known as cyclopia and a large majority of the severely affected children will die late in gestation or at birth. This condition can be inherited, but because the genetic lesions that cause this problem affect different people differently, people can carry the causative genetic change(s) without knowing it. We need to identify and study the genetic lesions that contribute to this condition in order to begin to understand how we can stop these mutations affecting the developing foetus. Because it is difficult to study embryonic development in humans we have generated a mouse model of this condition. In the mouse model just one gene (called Zic2) is altered and embryos that have two copies of this alteration develop the most severe form of cyclopia and die in the second half of gestation. This means that the normal role of this gene is to stop us developing HPE. We will use this mouse model to see just when and how the Zic2 gene prevents HPE. In addition, we will look to see what other genes Zic2 interacts with by breeding mice that carry the mutation in Zic2 with mice that carry a mutation in a second gene that can also cause HPE. These experiments are very important because if we understand how Zic2 and other genes protect us from HPE we can begin to design strategies to decrease the risk of a child developing this condition.Read moreRead less
The Role Of The Mammalian Grainyhead-like Gene Family In Neural Tube Closure
Funder
National Health and Medical Research Council
Funding Amount
$569,541.00
Summary
Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Anencephaly is not compatible with life and affected babies die at birth. In contrast children with spina bifida survive, but suffer from limb paralysis, bowel and bladder dysfunction, learning diff ....Failure of the skin to close over the brain and spinal cord during human development results in the devastating congenital birth defects anencephaly and spina bifida, known collectively as the neural tube defects. These are the second most common congenital birth defects affecting 1:1000 pregnancies. Anencephaly is not compatible with life and affected babies die at birth. In contrast children with spina bifida survive, but suffer from limb paralysis, bowel and bladder dysfunction, learning difficulties and psycho-social disturbances. Our laboratories have identified a family of genes essential for the colsure of the neural tube in mammals. The aim of this proposal is to understand the mechanisms of action with a view to developing new therapeutics that mey be used preventatively in these conditions. We also hope that these studies may facilitate the development of a genetic test to screen couples at risk.Read moreRead less
Biological, Functional And Radiographic Evaluation Of Autologous Chondrocyte Implantation
Funder
National Health and Medical Research Council
Funding Amount
$307,400.00
Summary
We will test the hypothesis that autologous chondrocyte implantation (ACI) and extensor realignment produces superior clinical, biological and radiographic results when compared with conventional treatment of realignment and debridement. We will specifically address the following aims: 1. Quantify the clinical outcome of ACI compared to the traditionally used treatment of debridement through the use of functional evaluation in a blinded randomised controlled clinical trial; 2. Evaluate the radio ....We will test the hypothesis that autologous chondrocyte implantation (ACI) and extensor realignment produces superior clinical, biological and radiographic results when compared with conventional treatment of realignment and debridement. We will specifically address the following aims: 1. Quantify the clinical outcome of ACI compared to the traditionally used treatment of debridement through the use of functional evaluation in a blinded randomised controlled clinical trial; 2. Evaluate the radiographic changes in the patellofemoral joint that occur as a result of ACI, using high resolution magnetic resonance imaging (MRI) to quantify the regeneration of hyaline articular cartilage; 3. Using the new technique of confocal arthroscopy, we will compare the histologic appearances of the ACI graft and its interface with adjacent articular cartilage; 4. Evaluate patient, surgical and explant chondrocyte characteristics in relation to functional, radiographic and biological outcomes. With respect to the matrix-induced autologous chondrocyte implantation (MACI) technique, we wish to clarify the clinical practice as a definitive treatment for articular cartilage defects. This will be the first randomised, controlled clinical trial of the MACI technique compared to that used by other groups. A positive clinical outcome from this trial will help promote the three cornerstones of this procedure – successful cell culture, efficient surgical procedures, and complimentary postoperative rehabilitation. Furthermore, this research will: a) Enhance the expansion of the MACI technique; b) Encourage development of endoscopic techniques of implantation using a combination of – • Preoperative defect registration with MRI • pre-cut custom patches, implanted with • Computer-assisted navigation techniques: c) Increase the potential to cater for a larger number of patients requiring articular cartilage repair; d) Confirm the long-term durability of regenerated cartilage in the 4th year and beyond; e) Add further commercial value by demonstrating MACI may prevent the onset of osteoarthritis.Read moreRead less
Identification And Characterisation Of Genes Required For Cardiac Morphogenesis
Funder
National Health and Medical Research Council
Funding Amount
$434,706.00
Summary
The heart is the first organ to become functional as an embryo forms, reflecting its critical role in sustaining life. Mistakes that occur as the heart develops have devastating consequences for an individualÍs survival and health. We have identified two zebrafish mutants with heart defects and, using sophisticated imaging and genetic studies, will investigate these defects and identify the genes responsible. This research will improve our understanding of correct and diseased heart formation.
Thalamic And Basal Forebrain Contributions To Auditory Cortical Reorganization Produced By Partial Hearing Loss
Funder
National Health and Medical Research Council
Funding Amount
$364,768.00
Summary
When part of the cochlea is damaged in adult animals, leading to a partial hearing loss, the auditory area of the cerebral cortex reorganizes itself, so that the area deprived of input by the peripheral lesion is not silent, but is occupied by expanded representations of adjacent frequencies. This reorganization has been observed in a number of species, including non-human primates, and it seems likely that it also occurs in humans with cochlear damage and hearing loss of this sort. If it does, ....When part of the cochlea is damaged in adult animals, leading to a partial hearing loss, the auditory area of the cerebral cortex reorganizes itself, so that the area deprived of input by the peripheral lesion is not silent, but is occupied by expanded representations of adjacent frequencies. This reorganization has been observed in a number of species, including non-human primates, and it seems likely that it also occurs in humans with cochlear damage and hearing loss of this sort. If it does, it would have important consequences for the way in which input from a hearing aid or cochlear prosthesis (bionic ear) is processed in the brain. This Project is designed to clarify the nature of the systems in the brain that contribute to this form of cortical plasticity, using an animal model. One aim is to determine whether the plasticity is intrinsic to the cortex or occurs in the pathways over which information is conveyed to the cortex. This will be assessed by determining whether such plasticity is also found in the auditory thalamus, the final subcortical auditory nucleus from which information is sent to the cortex. The second aim is to determine whether the occurrence of plasticity is controlled by modulatory influences from the basal part of the forebrain. Neurons in this area project to many parts of the cortex, and evidence from other sensory systems suggests that these projections exert a permissive function, allowing the cortex to reorganize when input is altered. This aim will be pursued by determining whether cortical reorganization occurs after hearing loss when this basal forebrain system is inactivated. The significance of these studies is that they will elucidate the way in which the brain reorganizes itself when it is confronted with altered input. This information is important for our understanding of normal auditory information processing mechanisms and of the way in which input from prosthetic devices is processed in the hearing-impaired.Read moreRead less
Identifying The Critical Pathways Which Regulate Vertebrate Craniofacial Development
Funder
National Health and Medical Research Council
Funding Amount
$552,131.00
Summary
Understanding the genes which underlie human birth defects is of immense clinical importance. Our laboratory is a world-leader investigating a gene responsible for facial skeleton development, Grhl2. With our wide range of models, we will discover how Grhl2 works to ensure the face and skull develop properly during birth.