Medicine and Health Sciences Commons^™

Serotypes And Virulence Gene Profiles Of Shiga Toxin-Producing Escherichia Coli Strains Isolated From Feces Of Pasture-Fed And Lot-Fed Sheep, Steven Djordjevic, Vidiya Ramachandran, Karl A Bettelheim, Barbara A. Vanselow, Peter Holst, Graham Bailey, Michael A. Hornitsky

Faculty of Science, Medicine and Health - Papers: part A

Shiga toxin-producing Escherichia coli (STEC) strains possessing genes for enterohemolysin (ehxA) and/or intimin (eae), referred to here as complex STEC (cSTEC), are more commonly recovered from the feces of humans with hemolytic uremic syndrome and hemorrhagic colitis than STEC strains that do not possess these accessory virulence genes. Ruminants, particularly cattle and sheep, are recognized reservoirs of STEC populations that may contaminate foods destined for human consumption. We isolated cSTEC strains from the feces of longitudinally sampled pasture-fed sheep, lot-fed sheep maintained on diets comprising various combinations of silage and grain, and sheep simultaneously grazing pastures …

Fish Recolonization In Temperate Australian Rockpools: A Quantitative Experimental Approach, Shane Griffiths, Ronald West, Andrew R. Davis, Ken Russell

Faculty of Science, Medicine and Health - Papers: part A

Understanding recolonization processes of intertidal fish assemblages is integral for predicting the consequences of significant natural or anthropogenic impacts on the intertidal zone. Recolonization of experimentally defaunated intertidal rockpools by fishes at Bass Point, New South Wales (NSW), Australia, was assessed quantitatively by using one long-term and two short-term studies. Rockpools of similar size and position at four sites within the intertidal zone were repeatedly defaunated of their fish fauna after one week, one month, and three months during two short-term studies in spring and autumn (5 months each), and every six months for the long-term study (12 months). Fish …

Plant Functional Traits In Relation To Fire In Crown-Fire Ecosystems, Juli G. Pausus, Ross Bradstock, David A. Keith, Jon E. Keeley

Faculty of Science, Medicine and Health - Papers: part A

Disturbance is a dominant factor in many ecosystems, and the disturbance regime is likely to change over the next decades in response to land-use changes and global warming. We assume that predictions of vegetation dynamics can be made on the basis of a set of life-history traits that characterize the response of a species to disturbance. For crown-fire ecosystems, the main plant traits related to postfire persistence are the ability to resprout (persistence of individuals) and the ability to retain a persistent seed bank (persistence of populations). In this context, we asked (1) to what extent do different life-history traits …

Immune Responses Of A Liposome/Iscom Vaccine Adjuvant Against Streptococcal Fibronectin Binding Protein 1 (Sfb1) In Mice, Jason D. Mcarthur, K Schulze, James Chin, B J. Currie, K S. Sriprakash, S R. Talay, G S. Chhatwal, C A. Guzman, Mark J. Walker

Faculty of Science, Medicine and Health - Papers: part A

BACKGROUND & OBJECTIVES: The fibronectin binding protein Sfb1 of Streptococcus pyogenes is a well characterised antigen which induces protection against lethal challenge with group A streptococcus (GAS) when adjuvanted with cholera toxin B-subunit (CTB). As an alternative to CTB adjuvanted intranasal immunisations we investigated the immune responses generated in mice using Sfb1 incorporated in to the skin and mucosal adjuvant SAMA4. METHODS: Mice (BALB/c) were vaccinated intradermally with 100 microl of either SAMA4 (adjuvant only group) or SAMA4/Sfb1 and were boosted 7 days later. Mice vaccinated with CTB based vaccines were immunised by intranasal inoculation with a mixture containing 30 …

Fibronectin-Binding Protein Gene Recombination And Horizontal Transfer Between Group A And G Streptococci, Rebecca J. Towers, Daniel Gal, David Mcmillan, Kadaba S. Sriprakash, Bart J. Currie, Mark J. Walker, Gursharan S. Chhatwal, Peter K. Fagan

Faculty of Science, Medicine and Health - Papers: part A

We report evidence of interspecies gene transfer between the important virulence factor genes sfbI and gfbA. Because the identified group G streptococcus gfbA types possess DNA cassettes that can be identified in a number of group A streptococcus strains, it appears that homologous recombination is occurring between these species.

Effects Of Ultraviolet Radiation And Visible Light On The Development Of Encapsulated Molluscan Embryos, Rachel Przeslawski, Andrew R. Davis, Kirsten Benkendorff

Faculty of Science, Medicine and Health - Papers: part A

Benthic egg masses laid in intertidal habitats are exposed to numerous environmental stresses including potentially damaging ultraviolet radiation (UVR). We sought to determine the developmental effects of UVR and visible light on molluscan embryos within egg masses from habitats with differential UVR exposure. Capsular and gelatinous egg masses from 23 marine gastropod species were collected from 3 intertidal habitats: (1) full sun, (2) partial shade, and (3) full shade. Egg masses were then divided among 4 spectral treatments: full spectrum, no UV-B, no UV, and dark. An ANOVA confirmed that a significant interaction between original habitat and spectral treatment affected …

Where Do Clonal Coral Larvae Go? Adult Genotypic Diversity Conflicts With Reproductive Effort In The Brooding Coral Pocillopora Damicornis, David J. Ayre, Karen Miller

Faculty of Science, Medicine and Health - Papers: part A

Earlier studies of the coral Pocillopora damicornis provide a conflicting picture of its use of sexual and asexual reproduction for population maintenance. In Western Australia, colonies are asexually viviparous, and populations appear to be maintained by localised asexual recruitment but founded by genotypically diverse colonists. However, on Australia¹s Great Barrier Reef (GBR), as in many other regions, populations display little or no evidence of any asexual recruitment. We used allozyme electrophoresis to test for asexual input into local populations of P. damicornis at One Tree Island on the southern GBR. Contrary to expectation we found that all of 136 planulae …

Effects Of Dexamethasone On Posterior Capsule Opacification-Like Changes In A Rat Lens Explant Model, Kylie Mansfield, Anna Cerra, Coral Chamberlain

Faculty of Science, Medicine and Health - Papers: part A

Purpose: Many patients whose sight is initially restored by cataract surgery eventually suffer secondary loss of vision because of posterior capsule opacification (PCO; after-cataract), a condition in which lens epithelial cells left behind at surgery become aberrant and migrate into the light path. The aim of this study was to determine whether dexamethasone (DEX), an anti-inflammatory agent widely used before and after cataract surgery, influences the behavior of lens cells under conditions relevant to PCO development.

Methods: An established rat PCO model was used in which explanted epithelial cells attached to the lens capsule are exposed sequentially to TGFβ2 and …

Fgf-2 Counteracts Loss Of Tgfβ Affected Cells From Rat Lens Explants: Implications For Pco (After Cataract), Kylie Mansfield, Anna Cerra, Coral Chamberlain

Faculty of Science, Medicine and Health - Papers: part A

Purpose: While cataract surgery initially benefits most patients, many suffer secondary loss of vision because of posterior capsule opacification (PCO). Lens epithelial cells left behind at surgery become aberrant and migrate into the light path. TGF-beta (TGFβ) appears to play a key role in this process by inducing the cells to undergo an epithelial-mesenchymal transition. Paradoxically, it also typically induces them to undergo apoptotic death. The present study was undertaken to investigate the hypothesis that FGF plays a role in PCO formation by promoting the survival of abnormal cells with PCO-like characteristics.

Methods: Rat lens epithelial explants were cultured for …

High Prevalence Of Hepatozoon Spp. (Apicomplexa, Hepatozoidae) Infection In Water Pythons (Liasis Fuscus) From Tropical Australia, Beata Ujvari, Thomas Madsen, Mats Olsson

Faculty of Science, Medicine and Health - Papers: part A

Molecular methods were used to identify blood parasites frequently observed in blood smears of water pythons (Liasis fuscus) captured in our study area in the Northern Territory of Australia. A nested polymerase chain reaction (PCR) using primers amplifying the 18s ribosomal RNA (rRNA) nuclear gene resulted in a short PCR product (180 bp) matching this region in the genus Hepatozoon. However, because of the short sequence obtained. 2 new primers were designed based on 18s rRNA sequences of 3 Hepatozoon taxa available in GenBank. Using these primers, approximately 600 bp of the parasite's 18s rRNA gene was amplified successfully and …

Sibudu Cave, Kwazulu-Natal: Background To The Excavations Of Middle Stone Age And Iron Age Occupations, Lyn Wadley, Zenobia Jacobs

Faculty of Science, Medicine and Health - Papers: part A

Sibudu Cave excavations have yielded an Iron Age occupation directly overlying a long sequence of final Middle Stone Age (MSA) layers dating c. 61 000-26 000 years ago. Older, undated layers contain a Howiesons Poort Industry. A diverse animal population is represented in the final MSA. Proxy environmental data suggest cooler, drier conditions with a larger savanna component to the vegetation than at present.

Gay And Lesbian Public History In Australia, Andrew Gorman-Murray

Faculty of Science, Medicine and Health - Papers: part A

Although scholarly interest in gay and lesbian history broadly defined is relatively young, research has increased significantly since the early 1990s. This was largely stimulated by the gay liberation movements of the 1970s and 1980s which both encouraged collective self-awareness amongst gays and sought acceptance from the broader straight society. During the 1990s gays became a significant 'consumer' group targeted by various companies and non-commercial organisations as a niche market. One need only scan through gay community periodicals such as SX or Sydney Star Observer to appreciate the number of businesses and non-commercial groups servicing the gay community. ln light …

Estimated Intake Of Milk Fat Is Negatively Associated With Cardiovascular Risk Factors And Does Not Increase The Risk Of A First Acute Myocardial Infarction. A Prospective Case-Control Study, Eva Warensjo, Jan-Hakan Jansson, Lars Berglund, Kurt Boman, Bo Ahren, Lars Weinehall, Bernt Lindahl, Goran Hallmans, Bengt Vessby

Faculty of Science, Medicine and Health - Papers: part A

Milk fat is high in saturated fatty acids (SFA) and high intakes of SFA are associated with cardiovascular diseases. The aim of the present study was to prospectively evaluate the potential risk of a first-ever acute myocardial infarction (AMI) in relation to the estimated milk-fat intake, reflected as the proportions of pentadecanoic acid (15:0) and heptadecanoic acid (17:0) in serum lipid esters. This was evaluated in a study population selected within the Västerbotten Intervention Program and the northern Sweden ‘Monitoring of Trends and Determinants in Cardiovascular disease’ survey populations. A prospective case–control design was used. The proportions of the biomarkers …

Minimum Energy As The General Form Of Critical Flow And Maximum Flow Efficiency And For Explaining Variations In River Channel Pattern, He Qing Huang, Howard H. Chang, Gerald Nanson

Faculty of Science, Medicine and Health - Papers: part A

Although the Bélanger-Böss theorem of critical flow has been widely applied in open channel hydraulics, it was derived from the laws governing ideal frictionless flow. This study explores a more general expression of this theorem and examines its applicability to flow with friction and sediment transport. It demonstrates that the theorem can be more generally presented as the principle of minimum energy (PME), with maximum efficiency of energy use and minimum friction or minimum energy dissipation as its equivalents. Critical flow depth under frictionless conditions, the best hydraulic section where friction is introduced, and the most efficient alluvial channel geometry …

Mapping Tropical Cyclone Disturbance Of The Great Barrier Reef, Marji Puotinen

Faculty of Science, Medicine and Health - Papers: part A

Tropical cyclones periodically cross the Great Barrier Reef (GBR). The large waves they generate can damage coral reefs. This paper will describe the challenges of mapping cyclone disturbance across such a vast geographic region, and how cartographic visualisation can help us understand the implications of these challenges on the quality of the results.

Diet And Metabolic Syndrome: Where Does Resistant Starch Fit In?, Linda C. Tapsell

Faculty of Health and Behavioural Sciences - Papers (Archive)

Metabolic syndrome is a term linking the clinical profiles of some of the world’s major health problems today: obesity, heart disease and diabetes. It is predicated on dietary patterns, and particularly on the delivery of fuel. The effects may be seen first in the development of abdominal obesity and insulin resistance leading to type 2 diabetes mellitus and coronary heart disease. This review examines the role resistant starch might play in the prevention and management of these conditions. Beginning with a definition of resistant starch, a critical review of the scientific literature is presented. Current knowledge suggests that resistant starch …

Jitter And Size Effects On Vection Are Immune To Experimental Instructions And Demands, Stephen A. Palmisano, Amy Y. Chan

Faculty of Health and Behavioural Sciences - Papers (Archive)

Both coherent perspective jitter and explicit changing-size cues have been shown to improve the vection induced by radially expanding optic flow. The current study examined whether these stimulus-based vection advantages could be modified by altering cognitions/expectations about both the likelihood of self-motion perception and the purpose of the experiment. In the main experiment, participants were randomly assigned into two groups – one where the cognitive conditions biased participants towards self-motion perception and another where the cognitive conditions biased them towards object motion perception. Contrary to earlier findings by Lepecq et al (1995), we found that identical visual displays were less …