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Articles 1 - 9 of 9
Full-Text Articles in Social and Behavioral Sciences
Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken
Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken
Heath Ecroyd
We investigated the role of endogenous redox activity in regulating the signal transduction pathway leading to tyrosine phosphorylation in mouse spermatozoa. Endogenous redox activity was monitored using a luminol-peroxidase chemiluminescent probe. Chemiluminescence increased in spermatozoa that were actively undergoing cAMP-mediated tyrosine phosphorylation events associated with capacitation and was inhibited in a dose-dependent manner by addition of catalase or diphenylene iodonium, both of which also inhibited tyrosine phosphorylation within the cell at points downstream of cAMP. Excluding bicarbonate from the incubation medium reduced the redox activity of sperm by 80-90% and dramatically reduced tyrosine phosphorylation. This study provides the first evidence …
The Effect Of Small Molecules In Modulating The Chaperone Activity Of Alpha B-Crystallin Against Ordered And Disordered Protein Aggregation, Heath Ecroyd, John Carver
The Effect Of Small Molecules In Modulating The Chaperone Activity Of Alpha B-Crystallin Against Ordered And Disordered Protein Aggregation, Heath Ecroyd, John Carver
Heath Ecroyd
Protein aggregation can proceed via disordered or ordered mechanisms, with the latter being associated with amyloid fibril formation, which has been linked to a number of debilitating conditions including Alzheimer's, Parkinson's and Creutzfeldt-Jakob diseases. Small heat-shock proteins (sHsps), such as alpha B-crystallin, act as chaperones to prevent protein aggregation and are thought to play a key role in the prevention of protein-misfolding diseases. In this study, we have explored the potential for small molecules such as arginine and guanidine to affect the chaperone activity of alpha B-crystallin against disordered (amorphous) and ordered (amyloid fibril) forms of protein aggregation. The effect …
The Two Faced Nature Of Milk Casein Proteins: Amyloid Fibril Formation And Chaperone-Like Activity, David Thorn, Heath Ecroyd, John Carver
The Two Faced Nature Of Milk Casein Proteins: Amyloid Fibril Formation And Chaperone-Like Activity, David Thorn, Heath Ecroyd, John Carver
Heath Ecroyd
Molecular chaperones are a diverse group of proteins that stabilise partially folded target proteins to prevent their misfolding, aggregation and potential precipitation under conditions of cellular stress, e.g. elevated temperature. Protein aggregation, particularly the formation of highly ordered protein aggregates termed amyloid fibrils, is of considerable research interest because of its intimate association with a wide range of debilitating diseases, including Alzheimer's, Parkinson's and Huntington's diseases and type II diabetes. In this review, we discuss the ability of the milk casein proteins to act in a chaperone-like manner. This property is of biological importance since at least two of the …
Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver
Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver
Heath Ecroyd
No abstract provided.
Activity Counts From Accelerometers Do Not Add Value To Energy Expenditure Predictions In Sedentary Overweight Individuals During Weight Loss Interventions, Sze Yen Tan, Marijka Batterham, Linda C. Tapsell
Activity Counts From Accelerometers Do Not Add Value To Energy Expenditure Predictions In Sedentary Overweight Individuals During Weight Loss Interventions, Sze Yen Tan, Marijka Batterham, Linda C. Tapsell
Faculty of Health and Behavioural Sciences - Papers (Archive)
Background: Knowing the total energy expenditure (TEE) of overweight adults is important for prescribing weight loss interventions. However, objective measurements of TEE may not always be readily available and can be expensive. This study aimed to investigate the validity of RT3 accelerometers in predicting the TEE of sedentary overweight adults, and to identify any sensitivity to anthropometric changes. Methods: The analysis used data from a 12-week weight loss study. At baseline and 12-week, TEE was predicted using RT3 accelerometers during whole room calorimeter stays. Bias between 2 methods was compared at and between the baseline and 12-week measurement points. Multiple …
Relationship Between Plantar Pressures, Physical Activity And Sedentariness Among Preschool Children, Karen J. Mickle, Dylan P. Cliff, Bridget J. Munro, Anthony D. Okely, Julie R. Steele
Relationship Between Plantar Pressures, Physical Activity And Sedentariness Among Preschool Children, Karen J. Mickle, Dylan P. Cliff, Bridget J. Munro, Anthony D. Okely, Julie R. Steele
Faculty of Health and Behavioural Sciences - Papers (Archive)
It has been speculated that high plantar pressures might cause foot pain and discomfort which, in turn, may discourage children from being physically active and result in them spending more time in sedentary activities. The purpose of this study was to determine whether plantar pressure distributions generated by preschool children were correlated with objectively measured time spent in physical activity and sedentary behaviour. Dynamic plantar pressures were measured for 33 preschool children (age = 4.3±0.6 years; height = 1.06±0.1 m; mass = 18.4±2.9 kg; 17 boys) as they walked across an emed AT-4 pressure platform. Physical activity was objectively assessed …
Effects Of Dairy Products On Crohn's Disease Symptoms Are Influenced By Fat Content And Disease Location But Not Lactose Content Or Disease Activity Status In A New Zealand Population, Deborah Nolan, Linda C. Tapsell, Rong Hu, Dug Yeo Han, Lynnette Ferguson
Effects Of Dairy Products On Crohn's Disease Symptoms Are Influenced By Fat Content And Disease Location But Not Lactose Content Or Disease Activity Status In A New Zealand Population, Deborah Nolan, Linda C. Tapsell, Rong Hu, Dug Yeo Han, Lynnette Ferguson
Faculty of Health and Behavioural Sciences - Papers (Archive)
Background Dairy products have been perceived as having the potential to cause adverse effects in individuals with Crohn’s disease (CD) and are often avoided, potentially increasing the risk of osteoporosis and related morbidity associated with inadequate dietary calcium intake. Objective To evaluate the self-reported effects of dairy products on CD symptoms and to determine whether these effects differed between types of dairy products consumed and disease state or location. Design Secondary analysis of dietary survey and clinical data from participants in the Genes and Diet in Inflammatory Bowel Disease study based in Auckland, New Zealand. Subjects/setting One hundred and sixty-five …
Wild Type And Tangier Disease Abca1 Mutants Modulate Cellular Amyloid-Beta Production Independent Of Cholesterol Efflux Activity, Kim S. Woojin, Andrew F. Hill, Michael L. Fitzgerald, Mason W. Freeman, Genevieve Evin, Brett Garner
Wild Type And Tangier Disease Abca1 Mutants Modulate Cellular Amyloid-Beta Production Independent Of Cholesterol Efflux Activity, Kim S. Woojin, Andrew F. Hill, Michael L. Fitzgerald, Mason W. Freeman, Genevieve Evin, Brett Garner
Faculty of Science - Papers (Archive)
Cerebral amyloid-β (Aβ) deposition is a critical feature of Alzheimer’s disease. Aβ is derived from the amyloid-β protein precursor (AβPP) via two sequential cleavages that are mediated by β-secretase and the γ-secretase complex. Such amyloidogenic AβPP processing occurs in lipid raft microdomains of cell membranes and it is thought that modulating the distribution of lipids in rafts may regulate AβPP processing and Aβ production. Certain ATP-binding cassette (ABC) transporters regulate lipid transport across cell membranes and, as recent studies reveal, within membrane microdomains. ABCA1 also regulates Aβ metabolism in the brain although its direct impact on AβPP remains an open …
Declining Physical Activity Levels As An Unintended Consequence Of Abolishing Mandatory Campus Service Fees, Sandra C. Jones, Lance R. Barrie
Declining Physical Activity Levels As An Unintended Consequence Of Abolishing Mandatory Campus Service Fees, Sandra C. Jones, Lance R. Barrie
Faculty of Health and Behavioural Sciences - Papers (Archive)
Objective: This study investigates the effect of the introduction of voluntary student unionism and subsequent increase in campus facility fees on engagement in physical activity on campus. Participants: Participants were 1,904 students from a large regional NSW (Australia) university across 3 time periods (926 in 2005, 504 in 2006, and 474 in 2007). Methods: Students completed a survey across the 3 time periods, responding to questions about physical activity levels, use of on-campus and off-campus facilities, and barriers to facility use. Results: Participation in physical activity at university facilities was low overall, and declined substantially between 2005 and 2007, with …