SCHOOL-AGE OUTCOME FOR VERY TINY/PRETERM CHILDREN BORN IN VICTORIA IN 1991-92
Funder
National Health and Medical Research Council
Funding Amount
$252,956.00
Summary
The survival rate for tiny or very premature babies has improved dramatically in recent times, from below 10% in the 1960s to greater than 70% in the 1990s. Several new treatments have helped to improve their survival rate, but some have the potential to cause long-term harm to the developing baby's brain or lung, and may cause lifelong problems with thinking, walking, talking, seeing, hearing, growth or breathing. Babies who are very tiny (born weighing less than 1000 g), or born very early (bo ....The survival rate for tiny or very premature babies has improved dramatically in recent times, from below 10% in the 1960s to greater than 70% in the 1990s. Several new treatments have helped to improve their survival rate, but some have the potential to cause long-term harm to the developing baby's brain or lung, and may cause lifelong problems with thinking, walking, talking, seeing, hearing, growth or breathing. Babies who are very tiny (born weighing less than 1000 g), or born very early (born before 28 weeks of pregnancy, or more than 12 weeks premature) will be assessed long term (to 8-9 years of age), as broadly as possible, and in comparison with normal birthweight (NBW, birthweight >2499 g) children. Outcomes will encompass academic progress and behaviour, brain function, general health, growth, and respiratory health. We will compare the outcomes for very tiny-preterm children who were treated with several of these new therapies with those who were not so treated. We will assess whether alternative measures of long term outcome that assess the quality of life are applicable to very tiny-preterm children. If so, these measures could be used much more widely, since they are cheaper and less time-consuming.Read moreRead less
Thousands of chemicals are used in Australian workplaces. For many of these chemicals it is not known if they are harmful to people who work with them. Unless we can measure how much of a chemical a worker has been exposed to, we cannot determine if the chemical is harmful. While we can test what chemicals a worker is currently exposed to, it is more difficult to estimate how much chemical exposure they have had in the past. This project aims to improve the ways we estimate past chemical exposur ....Thousands of chemicals are used in Australian workplaces. For many of these chemicals it is not known if they are harmful to people who work with them. Unless we can measure how much of a chemical a worker has been exposed to, we cannot determine if the chemical is harmful. While we can test what chemicals a worker is currently exposed to, it is more difficult to estimate how much chemical exposure they have had in the past. This project aims to improve the ways we estimate past chemical exposure. We will build on existing best-practice methods to improve occupational exposure assessment. New computer technology will be used to develop an intelligent evolving database that can be used when asking people about jobs they have had in the past. Experts can examine the answers to the questions to decide whether the worker was exposed to particular chemicals. New methods of processing information, called artificial neural networks, will be used to automate some of these decisions.Read moreRead less
Neural Mechanisms That Limit The Visual Sensitivity Of Primates
Funder
National Health and Medical Research Council
Funding Amount
$379,400.00
Summary
This project concerns the way nerve cells in the brain enable the detection and perception of objects in the visual world. It is thought that nerve cells early in the visual pathway signal the presence or absence of light in a small part of the visual field, but the nature of the neuronal code carried by these pathways remains poorly understood. The aim of our project is to address this basic question, in experimental studies of the intact primate visual system. We will conduct two sets of exper ....This project concerns the way nerve cells in the brain enable the detection and perception of objects in the visual world. It is thought that nerve cells early in the visual pathway signal the presence or absence of light in a small part of the visual field, but the nature of the neuronal code carried by these pathways remains poorly understood. The aim of our project is to address this basic question, in experimental studies of the intact primate visual system. We will conduct two sets of experiments. Firstly, we will test the hypothesis that nerve cells in the early visual system are sensitive to only a small part of the visual field. We will determine whether the signals of pre-cortical nerve cells are dependant on spatial context. Secondly we wll study the signals of several nerve cells simultaneously using multiple electrodes. We will determine if the signals of many nerve cells are required to detect small visual stimuli like those used in perimetry. These experiments address basic questions, but have application to human vision and visual dysfunction. Good acuity is essential for everyday tasks such as reading, and defects in visual sensitivity are used for early detection of neurological dysfunction in diseases such as glaucoma and macular degeneration. Understanding the properties of neurons which underlie visual perception can thus help us to understand normal visual performance, and how this changes in partial sight. This can help develop better methods for detection and treatments for such disorders.Read moreRead less
Artificial joint implants are widely used to replace diseased or damaged joints. Despite the impressive success of joint replacement many artificial joints do not last indefinitely. In many patients joints last for 25 years or more but in about 15% the artificial joints will fail prematurely. Artificial joints need to be replaced because of loosening resulting from the loss of bone from around the artificial joint. The bone loss is caused by large numbers of small particles generated by excessiv ....Artificial joint implants are widely used to replace diseased or damaged joints. Despite the impressive success of joint replacement many artificial joints do not last indefinitely. In many patients joints last for 25 years or more but in about 15% the artificial joints will fail prematurely. Artificial joints need to be replaced because of loosening resulting from the loss of bone from around the artificial joint. The bone loss is caused by large numbers of small particles generated by excessive wear of the artificial joint. We now know that specialised cells in the body react to the wear particles and try to destroy them. During this process they produce molecules which lead to bone destruction. This project seeks to investigate the way particles cause bone loss and to develop drug treatments that will either prevent the loss of bone or promote new bone to replace that which has been lost. The increasing use of joint replacement and an aging population means that the number of patients with artificial joint failure will increase. This will mean that an increasing amount of medical recourses will be needed to replace failed and painful artificial joints. It is planned that the findings obtained from this project will eventually result in drug treatments which can reduce the need for the replacement of artificial joints.Read moreRead less
Atherosclerosis (hardening of the arteries) is the principal cause of heart attack, stroke and blockage of blood flow to the lower limbs. However, to date none of the biological or synthetic grafts used to bypass the narrowed regions of arteries is ideal. We have shown that lengths of silicone tubing placed into the peritoneal cavity of rats or rabbits becomes covered within 2 weeks by a capsule of granulation tissue (smooth-muscle-like cells and collagen) and mesothelial (endothelial-like) cell ....Atherosclerosis (hardening of the arteries) is the principal cause of heart attack, stroke and blockage of blood flow to the lower limbs. However, to date none of the biological or synthetic grafts used to bypass the narrowed regions of arteries is ideal. We have shown that lengths of silicone tubing placed into the peritoneal cavity of rats or rabbits becomes covered within 2 weeks by a capsule of granulation tissue (smooth-muscle-like cells and collagen) and mesothelial (endothelial-like) cells. The silicone tubing can be removed and the tissue turned inside out such that the endothelial-like cells now line the inside of the tube of living tissue, which resembles a blood vessel. These artificial blood vessels will be grown in the peritoneal cavity of rabbits, then grafted into the right carotid artery to replace a length of removed vessel. Their long-term (3,6,9 and 12 months) patency, reactivity, tensile strength and resistance to clot development will be assessed. Their susceptibility to atherosclerotic plaque development and blockage (as compared with natural carotid artery) will be examined in rabbits fed a cholesterol-enriched diet. Changes in gene expression as the artificial artery progressively develops will be examined, as will the potential to genetically manipulate the artificial artery to improve its functioning. Finally, attempts will be made to grow the vessels entirely in vitro. This novel vascular graft may open new options in the field of arterial reconstructive surgery for replacing or bypassing diseased vessels or as an access vessel for haemodialysis patients with end stage renal failure. This study will also provide new information on the biology of cells found in the peritoneal cavity and their alternative pathways for differentiation.Read moreRead less
Effects Of Lead And Socio-cultural Factors On Cognition And Behaviour Of Children In Port Pirie And Broken Hill
Funder
National Health and Medical Research Council
Funding Amount
$394,825.00
Summary
The effect of lead on children's 'intelligence' is controversial. Poorer IQ scores in children with higher exposure to lead, have been found reasonably consistently, - but there is disagreement on whether lead exposure is simply a common ASSOCIATE of poor IQ, or whether it actually CAUSES deficits. In 1994, the NHMRC prudently recommended a graded series of interventions to be implemented, depending on the proprtion of children in the community with blood lead concentrations in specific categori ....The effect of lead on children's 'intelligence' is controversial. Poorer IQ scores in children with higher exposure to lead, have been found reasonably consistently, - but there is disagreement on whether lead exposure is simply a common ASSOCIATE of poor IQ, or whether it actually CAUSES deficits. In 1994, the NHMRC prudently recommended a graded series of interventions to be implemented, depending on the proprtion of children in the community with blood lead concentrations in specific categories above 10 ug lead -100 ml of blood. The choice of this figure (10 ug-dl) was more pragmatic than scientific; there being very little data on the health effects of exposures below 10 ug-dl available at that time. A recent analysis of pooled data from past studies has now suggested there may be very large effects on child IQ at blood lead concentration BELOW 10 ug-dl. Health authorities will soon be lobbied intensely to spend vast sums on new lead abatement programs. Cities like Port Pirie and Broken Hill (where cooperative programs have achieved such significant reductions in lead exposure that a high percentage of their children now have blood lead levels below 10 ug-dl), will be forced to examine expensive options to avoid closure of the industries which provide their economic backbones, if this analysis proves to be correct. Our proposal argues that before committing to new and costly abatement programs, there is an urgent need to augment our evidence-base by conducting a new study ofchildren with lead exposures below 10 ug-dl, using more modern measures of intelligence. The study will pay closer attention to some of the socio-cultural and inherited determinants of child IQ which may have confounded the lead-IQ association in past studies, and will supplement IQ assessments (which are now considered to derive from a very old and narrow view of intelligence) with new tools for measuring 'intelligence' that may be less socio-culturally dependent.Read moreRead less
Regulation And Activity Of Fatty Acid Delta-6 Desaturase (D6D)
Funder
National Health and Medical Research Council
Funding Amount
$527,683.00
Summary
Fish and fish oils contain fats known as omega-3 fats. These have health benefits in adult conditions such as rheumatoid arthritis and heart disease, and they are necessary for proper brain and eye development in infants. However, much of the population does not like to eat fish and also, world fish stocks are under stress. Thus, a sustainable alternative source of omega-3 fats needs to be explored. Some vegetable oils such as canola, echium, and flaxseed oils have omega-3 fats. However, these a ....Fish and fish oils contain fats known as omega-3 fats. These have health benefits in adult conditions such as rheumatoid arthritis and heart disease, and they are necessary for proper brain and eye development in infants. However, much of the population does not like to eat fish and also, world fish stocks are under stress. Thus, a sustainable alternative source of omega-3 fats needs to be explored. Some vegetable oils such as canola, echium, and flaxseed oils have omega-3 fats. However, these are not the same as the omega-3s in fish oil. In general, vegetable omega-3s are known as short-chain omega-3s whereas those in fish are long-chain. When the vegetable oil omega-3s are consumed in the diet, the body must convert them to the fish-type, or long-chain, omega-3s in order to gain the health benefits. Currently, human metabolism is poor at doing this conversion. Our studies suggest that the amounts and blends of fats in most diets are well below optimal for conversion to long-chain omega-3s in the body. In particular, our studies show that there may be no point in simply adding more vegetable omega-3 fats to the diet. This project will examine the enzymes that convert the short-chain to the long-chain omega-3 fats. In particular, it will examine how the dietary fats interact with each other in detrimental ways to suppress activity of the conversion enzymes necessary for long-chain omega-3 formation. Evidence for the health benefits of fish-based omega-3 fats is very strong and it is an approach to health that most people can undertake on their own. Our lack of knowledge of the best way to use plant-based omega-3 fats is a large impediment for a more sustainable and broader based use of omega-3 fats. The results from this study will begin to fill in this knowledge gap. The results will be useful across a range of activities that are determinants of the kinds of fat that we eat. These include oil seed breeding, food manufacture, and dietetics.Read moreRead less