The Role Of Arousal And Respiratory Control Factors In The Pathogenesis Of Obstructive Sleep Apnoea
Funder
National Health and Medical Research Council
Funding Amount
$567,924.00
Summary
Sleep apnoea (OSA) is a very common breathing disorder in sleep characterized by repetitive closure of the collapsible portion of the throat with serious effects on sleep quality and health. Basic causes of OSA are still largely unknown. We will investigate waking responses to breathing load and related respiratory control factors that we believe may be fundamental causes of OSA, and potentially explain many features of OSA including worsening in light sleep and with increasing age.
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.
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.
We will seek to address an important clinical problem in orthpaedics, namely the bone loss that commonly occurs around joint replacement prostheses. Termed peri-prosthetic osteolysis (PO), this bone loss can result in the loosening and ultimate failure and need for revision of the artificial joint components. PO is thought to be caused by the body's reaction to wear particles generated from the articulating surface of the prosthesis. However, it has not previously been possible to accurately exp ....We will seek to address an important clinical problem in orthpaedics, namely the bone loss that commonly occurs around joint replacement prostheses. Termed peri-prosthetic osteolysis (PO), this bone loss can result in the loosening and ultimate failure and need for revision of the artificial joint components. PO is thought to be caused by the body's reaction to wear particles generated from the articulating surface of the prosthesis. However, it has not previously been possible to accurately explore the relationship between prothesis wear and PO, or the progression of PO, because of a lack of techniques to image and measure the volume of PO around metal prosthesis components. We have developed a means to accurately and reproducibly measure the volume of bone loss, using CT, and will do so longitudinally in joint replacement patients to obtain the first information about the progression of PO. New computer based methods will be used concurrently to relate prosthesis wear and migration parameters to PO. Patients who come to surgery for replacement of failed prostheses will be investigated further by analysis of the tissues involved in the bone loss around prostheses. Basic science experiments will seek to understand the underlying causes of PO and the findings will be important in interpreting the clinical results. An animal model will be used to seek approaches to inhibiting the pathological response to wear particles. The significance of these studies is that they will lead to improved outcomes for joint replacement patients, increasing the interval to revision surgery, which is both extremely costly and brings an attendant morbidity and mortality.Read moreRead less
Tapasin And Major Histocompatibility Complex Class I Antigen Presentation
Funder
National Health and Medical Research Council
Funding Amount
$226,650.00
Summary
An effective T cell response (cellular immune response) to infections is vital to a functional immune system. Normally, proteins are cleaved into small molecules called peptides and these peptides are in turn presented by Major Histocompatibility Complex molecules to T cells. However, we have only partial understanding of what determines the choice of peptides that are finally presented to T cells. Recent research suggests that a molecule called tapasin may also influence the choice of peptides. ....An effective T cell response (cellular immune response) to infections is vital to a functional immune system. Normally, proteins are cleaved into small molecules called peptides and these peptides are in turn presented by Major Histocompatibility Complex molecules to T cells. However, we have only partial understanding of what determines the choice of peptides that are finally presented to T cells. Recent research suggests that a molecule called tapasin may also influence the choice of peptides. This research proposal aims to examine the role of tapasin in this regard. A thorough understanding of the basic principles of peptide presentation to T cells is crucial to the design of effective vaccines. Furthermore it will also broaden our understanding of immunological responses to cancer, autoimmune diseases and infections.Read moreRead less
The Role Of Arousal And Diaphragm Displacement In The Pathogenesis Of Obstructive Sleep Apnoea
Funder
National Health and Medical Research Council
Funding Amount
$410,875.00
Summary
Obstructive sleep apnea (OSA) affects 4% of men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease e.g. heart attacks and strokes. OSA is characterized by repetitive obstructions of the floppy portion of the throat during sleep with adverse effects on oxygen levels and sleep quality. OSA is strongly associated with obesity and is 2-3 times more common in men than women. How obesity and male gender predispose to OSA is ....Obstructive sleep apnea (OSA) affects 4% of men and causes excessive daytime sleepiness leading to increased accidents, high blood pressure and premature cardiovascular disease e.g. heart attacks and strokes. OSA is characterized by repetitive obstructions of the floppy portion of the throat during sleep with adverse effects on oxygen levels and sleep quality. OSA is strongly associated with obesity and is 2-3 times more common in men than women. How obesity and male gender predispose to OSA is not known. We will investigate two factors that we believe are most likely involved in causing and explaining this gender difference in OSA. We will examine if breathing responses with brief awakening are sufficient to promote OSA patterns of breathing in snorers and if they are greater in male than female OSA patients. We have already shown that healthy men have greater breathing response to arousal compared to women. These brief arousals occur hundreds of times a night in OSA patients, and over-breathing on arousal may increase the probability of upper airway obstruction on falling back to sleep. We will also investigate why even healthy men show greater breathing responses compared to women. Men tend to accumulate fat centrally, particularly in the abdomen, whereas in women fat tends to be distributed more to the hips and thighs. This could be very important in OSA because downward pull exerted on the upper airway by the diaphragm is likely to be reduced in people with more abdominal obesity. This mechanisms has not yet been studied in humans. We will therefore investigate if increased forces placed on the diaphragm during sleep make the upper airway more prone to collapse. We will also investigate these effects during sleep onset, when there may well be important changes in diaphragm position as muscles relax.Read moreRead less
Role Of Zinc In The Respiratory Epithelium And Asthma
Funder
National Health and Medical Research Council
Funding Amount
$224,250.00
Summary
This project will use a panel of Zinquin-derived Zn fluorophores developed in our laboratory, as well as probes for the mammalian family of vesicular ZnT transporters, to carry out a study of the normal physiology of Zn in the respiratory system and potential abnormalities of this in patients with chronic inflammatory respiratory disease (asthma, COPD, chronic smoking). Chronic inflammatory diseases of the respiratory tract affect a significant proportion of the Australian community. For example ....This project will use a panel of Zinquin-derived Zn fluorophores developed in our laboratory, as well as probes for the mammalian family of vesicular ZnT transporters, to carry out a study of the normal physiology of Zn in the respiratory system and potential abnormalities of this in patients with chronic inflammatory respiratory disease (asthma, COPD, chronic smoking). Chronic inflammatory diseases of the respiratory tract affect a significant proportion of the Australian community. For example, asthma affects 12% of adults and amongst these, 15% waken weekly or more often with their asthma while 6% are hospitalized annually. There is a need to understand the basic mechanisms underlying these diseases so that new strategies can be developed to modify bronchocondtriction and inflammation. The project will provide new knowledge concerning the physiology of Zn in the respiratory epithelium and interactions between Zn deficiency and oxidants on injury in the respiratory tract. The usefulness of easily accessible nasal epithelial cells as a measure of Zn and Zn transporter levels deeper in the respiratory tract will be assessed. The project encompasses a number of fields and utilizes in vitro cellular and animal models, as well as tissues from human subjects.Read moreRead less
MICROFABRICATED DEVICES: A SIGNIFICANT ADVANCE FOR THE DETECTION AND MOLECULAR ANALYSES OF CIRCULATING CANCER CELLS?
Funder
National Health and Medical Research Council
Funding Amount
$422,107.00
Summary
Using advanced microfabrication concepts, this project aims to develop a platform technology able to capture tumour cells circulating in the blood of cancer patients. Although present only in extremely small numbers, these cells provide invaluable insights into the pathophysiology of the disease and consequently provide vital diagnostic and prognostic information. Molecular analyses of these cancer cells could ultimately enable the design of improved and personalized cancer treatment.