Hypoxia-induced Suppression Of Respiratory Sensations And Reflexes
Funder
National Health and Medical Research Council
Funding Amount
$276,750.00
Summary
Many diseases that effect the respiratory system have their primary effect on the lungs and airway themselves but in some conditions, such as obstructive sleep apnea (OSA) and asthma, increased breathing load can induce periods of low blood oxygen which could further contribute to morbidity in these diseases. OSA is a disorder associated with snoring. Patients experience periods of sleep fragmentation and oxygen deprivation due to obstruction of the floppy portion of the upper airway (pharynx) d ....Many diseases that effect the respiratory system have their primary effect on the lungs and airway themselves but in some conditions, such as obstructive sleep apnea (OSA) and asthma, increased breathing load can induce periods of low blood oxygen which could further contribute to morbidity in these diseases. OSA is a disorder associated with snoring. Patients experience periods of sleep fragmentation and oxygen deprivation due to obstruction of the floppy portion of the upper airway (pharynx) during sleep. It affects 4% of men and 2% of women and causes excessive daytime sleepiness leading to increased risk of accidents, high blood pressure and premature cardiovascular disease. Asthma produces airway inflamation and narrowing and affects a wide range of people. Both OSA and asthma are associated with episodes of impaired breathing and reduced levels of oxygen in the blood. Low levels of oxygen in the blood (hypoxia) is well known to impair functioning of the central nervous system. We have recently found that hypoxia blunts sensations of increased breathing load in healthy people and in asthmatics. Hypoxia might therefore contribute to worsening of attacks in these diseases. This study aims to investigate how changes in blood oxygen levels affect brain processing of respiratory signals, how this translates to perception of sensations and the physiological adaptations that people make to cope with increased breathing load. We will also investigate whether the inhibitory effects of hypoxia on central nervous system function extend to other vital protective respiratory reflexes such as cough, awakening from sleep to increased breathing load and upper airway reflexes that are important for maintaining an open airway.Read moreRead less
Asthma Prevention And Treatment Using UVB Radiation-induced Immunomodulation
Funder
National Health and Medical Research Council
Funding Amount
$496,446.00
Summary
The prevalence of asthma is increasing despite the adoption of modern expensive drugs. Our studies suggest that exposure of skin to an erythemal dose of the wavelengths of UVB radiation found in sunlight can suppress responses to allergens encountered in the airways. We are requesting support to study the mechanisms in mice by which exposure to UVB radiation on their shaved backs can reduce inflammation in the airway mucosa upon allergen exposure. Whole body immunomodulatory effects of UVB radia ....The prevalence of asthma is increasing despite the adoption of modern expensive drugs. Our studies suggest that exposure of skin to an erythemal dose of the wavelengths of UVB radiation found in sunlight can suppress responses to allergens encountered in the airways. We are requesting support to study the mechanisms in mice by which exposure to UVB radiation on their shaved backs can reduce inflammation in the airway mucosa upon allergen exposure. Whole body immunomodulatory effects of UVB radiation have been previously described but have not been scientifically linked with asthma development. This is a very new and novel research area which supports century-old anecdotal reports that holidays at beach and mountain resorts associated with increased UVB exposure are beneficial in asthma treatment. This is a proof of principle study. If we can confirm that UVB is immunomodulatory and better understand the mechanisms by which UVB suppresses inflammation in the airways, we will investigate the potential of non-carcinogenic, UVB-induced, skin-derived intermediary molecules to have the same regulatory effects.Read moreRead less
A Novel Strategy Targeting Quorum Sensing Molecules And Catalase Function To Block Pseudomonas Aeruginosa Lung Infection
Funder
National Health and Medical Research Council
Funding Amount
$451,118.00
Summary
Pseudomonas aeruginosa causes serious infections, particularly in those with Cystic Fibrosis, immunocompromise, serious burns or long term catheters. We will use a unique strategy to target virulence factors that will assist in clearing acute infection, prevent establishment of new chronic infections, and potentially reduce severity of established chronic infections. It has the potential to make antibiotic therapy more effective and lessen the extent of antibiotic therapy required.
Quorum Sensing Signal Molecule Modulation Of Immunity: Role In Host Responses To P. Aeruginosa Lung Infection
Funder
National Health and Medical Research Council
Funding Amount
$251,014.00
Summary
Pseudomonas aeruginosa is a bacterium that causes serious infections in humans, particularly those with Cystic Fibrosis, or who are immunocompromised, suffering serious burn injuries or have long term catheters. This study will investigate how P. aeruginosa may be able to increase its virulence by producing molecules known as Quorum Sensing Signal Molecules (QSSM). We believe the production of these QSSMs by this bacterium enables them to affect how the host responds by affecting their immune sy ....Pseudomonas aeruginosa is a bacterium that causes serious infections in humans, particularly those with Cystic Fibrosis, or who are immunocompromised, suffering serious burn injuries or have long term catheters. This study will investigate how P. aeruginosa may be able to increase its virulence by producing molecules known as Quorum Sensing Signal Molecules (QSSM). We believe the production of these QSSMs by this bacterium enables them to affect how the host responds by affecting their immune system. We will be investigating how this QSSM may suppress immunity and what influence this has on both the severity of infection and the potential for development of chronic infection. The study will first of all determine where the QSSM exerts its effects (that is, can it escape from the site of infection to affect other host sites) and this will direct us in how we may learn more about the way it can affect the host during an infection. We will investigate the direct affects of QSSM on acute and chronic types of P. aeruginosa lung infection and then from this, determine if the outcome exacerbates a subsequent infection. The work is significant in that a knowledge and understanding of these virulence factors will assist in the design of better therapeutic and prophylactic strategies for both prevention of infection in susceptible individuals and treatment of those that suffer from chronic infection.Read moreRead less