Enhancing The Cardioprotective Effect Of Diadenosine Tetraphosphate: Designing Inhibitors Against Ap4A Hydrolase
Funder
National Health and Medical Research Council
Funding Amount
$442,500.00
Summary
Ischemia describes the condition where blood flow in the blood vessels of the heart is decreased or blocked, preventing delivery of oxygen and nutrients to the heart. Ischemic preconditioning is a phenomenon where short bursts of ischemia, followed by reperfusion, actually protect the heart from a subsequent longer period of ischemia. The biochemical signalling events involved in preconditioning are complex and incompletely defined, but most likely involve multiple pathways, although the mitocho ....Ischemia describes the condition where blood flow in the blood vessels of the heart is decreased or blocked, preventing delivery of oxygen and nutrients to the heart. Ischemic preconditioning is a phenomenon where short bursts of ischemia, followed by reperfusion, actually protect the heart from a subsequent longer period of ischemia. The biochemical signalling events involved in preconditioning are complex and incompletely defined, but most likely involve multiple pathways, although the mitochondrial ATP-dependent potassium channel may be in common with most pathways. Pretreatment with the compound diadenosine tetraphosphate (Ap4A) mimics ischemic preconditioning with noticeable reductions in tissue necrosis (cell death). This treatment has been shown in experimental work to protect the heart during periods of stress such as in heart surgery or recovery from an ischemic event. The biological site of action by Ap4A may be the mitochondria ATP-dependent potassium channel or an associated protein. Ap4A can be degraded by enzymes located inside and on the outside of heart cells, notably by two forms of Ap4A hydrolase. We will use antibody assays to understand the specific localization and amount of Ap4A hydrolase before and after ischemia and after ischemic preconditioning in human heart muscle and blood vessels. We propose to determine the structure of the enzyme and use novel computer methods to screen databases for potential inhibitors. These inhibitors of Ap4A hydrolase activity could aid the design of a potent inhibitor that would prevent Ap4A hydrolase from degrading Ap4A and therefore enhance the cardioprotective properties of Ap4A as well as minimizing side effects from the break down of Ap4A. We will also use these inhibitors and other known non-degradable Ap4A analogues in bioassays to test the relative significance of Ap4A hydrolase present in different cellular locations.Read moreRead less
A Randomised Controlled Trial Examining Stability Of New Types Of Highly Porous Surfaced Acetabular Components In Total Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$216,490.00
Summary
Numbers of total hip replacements are steadily increasing. The most common complication of hip replacement is late implant loosening, which can be predicted by early migration. We will examine early migration of a trabecular metal acetabular cup without screws, compared to a titanium fibre metal acetabular cup fixed with screws. Ideally, an acetabular cup would achieve a level of initial stability by press-fit alone without screws, as screws increase the risk of bone loss around the prosthesis.
Antagonist Of Corticotrophin Releasing Hormone As Therapeutic Agents For The Prevention Of Premature Birth In Humans
Funder
National Health and Medical Research Council
Funding Amount
$376,650.00
Summary
In developed countries the most common cause of the death of a newborn baby is premature delivery. Pre-term delivery remains the greatest cause of neonatal mortality in the western world and a major consumer of health dollars (approx. $5-7B per year in the US alone). However, a delay in the onset of labour from 20 to 25 weeks has been shown to result in a 55% greater probability of infant survival (550 fewer deaths per 1000). This project will allow: The development of new drugs that will allow ....In developed countries the most common cause of the death of a newborn baby is premature delivery. Pre-term delivery remains the greatest cause of neonatal mortality in the western world and a major consumer of health dollars (approx. $5-7B per year in the US alone). However, a delay in the onset of labour from 20 to 25 weeks has been shown to result in a 55% greater probability of infant survival (550 fewer deaths per 1000). This project will allow: The development of new drugs that will allow the extension of pregnancy term The development of protocols that will in turn reduce neonatal mortality. Additionally we believe that these new agents will be useful in preventing the onset of labour after fetal surgery. Currently there are no effective treatments capable of substantially changing delivery dates. Available therapeutics delay the onset of labour, at best, 24 hours. However, recent exciting results from our laboratories show that rising concentrations of the placental peptide Corticotrophin Releasing Hormone (CRH) are associated with the onset of labour. Further, we have also delayed the onset of labour in pregnant sheep by infusing a relatively insoluble CRH antagonist into the sheep fetus. Labour commenced ONLY AFTER the drug was withdrawn from the mother. This project builds upon an interdisciplinary team: medicinal chemists, molecular modellers, pharmacologists and endocrinologists, to further develop an exciting Australian discovery. Successful completeion of this research will, for the first time, allow the control of pregnancy duration MAXIMISING the benefits to mother and child, reducing mortality and later life morbidities typically associated with premature birth.Read moreRead less
New High-risk Variants For Colorectal Cancer: The Post-GWAS Era
Funder
National Health and Medical Research Council
Funding Amount
$710,105.00
Summary
Our aim is to discover new genes that greatly increase bowel cancer risk. If we can identify these carriers we may be able to prevent them getting cancer. By studying DNA related to bowel cancer, using a novel family design, we will identify families most likely to carry the new genes. We will focus genetic testing, using new techniques, to look for mutations in these prioritised families. Identified mutations will be tested in a 3,500 bowel cancer cases to see how important they are.
The Impact Of Outdoor Aeroallergen Exposure On Asthma Exacerbations In Children And Adolescents
Funder
National Health and Medical Research Council
Funding Amount
$473,924.00
Summary
Asthma is a chronic condition usually diagnosed in childhood and an important public health concern. We do not fully understand what triggers an asthma attack, although outdoor pollen and moulds may be important. This project will establish the relative importance of pollen and moulds in triggering asthma attacks among Australian children. It will fill gaps in our knowledge of environmental triggers of asthma. Such knowledge will improve asthma management and ultimately public health.
Throughout our lives cells must die and be replenished. One way multicellular organisms remove unwanted cells is through a process called programmed cell death. This process eliminates redundant, damaged or infected cells by a program of cell suicide. We are studying the underlying molecular mechanisms of this cell suicide in order to design new pharmaceuticals to treat illnesses caused by a disruption in programmed cell death. The fine balance between living and dying cells must be maintained a ....Throughout our lives cells must die and be replenished. One way multicellular organisms remove unwanted cells is through a process called programmed cell death. This process eliminates redundant, damaged or infected cells by a program of cell suicide. We are studying the underlying molecular mechanisms of this cell suicide in order to design new pharmaceuticals to treat illnesses caused by a disruption in programmed cell death. The fine balance between living and dying cells must be maintained and if this balance is lost then disease may result. A reduced level of cell death may result in cancers while too many dying can contribute to degenerative diseases such as Alzheimer's disease and stroke. Currently many of these diseases do not have effective treatments. We will determine the three-dimensional structures of key proteins involved in programmed cell death and use this information to design drugs that can interfere with the molecular processes involved in signalling cell death. Such drugs may prove useful new therapies in a wide range of diseases caused by a breakdown in the biochemical paths to cell death.Read moreRead less
The Risks And Benefits Of Contemporary Total Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$493,530.00
Summary
The number of hip replacements undertaken in Australia is steadily increasing. The most common complications of hip replacements are dislocation and loosening due to bone loss around the implant, requiring complex and expensive revision surgery. This study will investigate the incidence of dislocation and, using a new diagnostic imaging technique, the incidence and amount of bone loss around a relatively new prosthetic material, the outcomes of which are not known despite its increasing use.
Radiostereometric Analysis Of The Effect Of A Large Articulation On Prosthetic Wear And Migration After Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$192,186.00
Summary
At total hip replacement, there has been a recent trend to use prostheses with a larger ball and liner in the socket. This may decrease the risk of post-operative dislocation, but may also increase the amount of wear, leading to bone loss and loosening of prostheses, which may then require replacement. This project will use a special type of x-ray to determine whether wear and movement of these new prostheses is clinically acceptable, so that they can be used with confidence in patients.