Weaving the past into the present : Indigenous stories of education across generations

In Queensland, there is little research that speaks to the historical experiences of schooling. Aboriginal education remains a part of the silenced history of Aboriginal people. This thesis presents stories of schooling from Aboriginal people across three generations of adult storytellers. Elders, grandparents, and young parents involved in an early childhood urban playgroup were included. Stories from the children attending the playgroup were also welcomed. The research methodology involved narrative storywork. This is culturally appropriate because Aboriginal stories connect the past with the present. The conceptual framework for the research draws on decolonising theory. Typically, reports of Aboriginal schooling and outcomes position Aboriginal families and children within a deficit discourse. The issues and challenges faced by urban Murri families who have young children or children in school are largely unknown. This research allowed Aboriginal families to participate in an engaged dialogue about their childhood and offered opportunities to tell their stories of education. Key research questions were: What was the reality of school for different generations of Indigenous people? What beliefs and values are held about mainstream education for Indigenous children? What ideas are communicated about school across generations? Narratives from five elders, five grandparents, and five (urban) mothers of young Indigenous children are presented. The elders offer testimony on their recollected experiences of schooling in a mission, a Yumba school (fringe-dwellers’ camp), and country schools. Their stories also speak to the need to pass as non-indigenous and act as “white”. The next generation of storytellers are the grandparents and they speak to their lives as “stolen children”. The final story tellers are the Murri parents. They speak to the current and recent past of education, as well as their family experiences as they parent young children who are about to enter school or who are in the early years of school.

Camera trapping and invasions of privacy : an Australian legal perspective

Camera trapping is a scientific survey technique that involves the placement of heat-and motion-sensing automatic triggered cameras into the ecosystem to record images of animals for the purpose of studying wildlife. As technology continues to advance in sophistication, the use of camera trapping is becoming more widespread and is a crucial tool in the study of, and attempts to preserve, various species of animals, particularly those that are internationally endangered. However, whatever their value as an ecological device, camera traps also create a new risk of incidentally and accidentally capturing images of humans who venture into the area under surveillance. This article examines the current legal position in Australia in relation to such unintended invasions of privacy. It considers the current patchwork of statute and common laws that may provide a remedy in such circumstances. It also discusses the position that may prevail should the recommendations of either the Australian Law Reform Commission and/or New South Wales Law Reform Commission be adopted and a statutory cause of action protecting personal privacy be enacted.

The role of prostacyclin synthase and thromboxane synthase signaling in the development and progression of cancer

Prostacyclin synthase and thromboxane synthase signaling via arachidonic acid metabolism affects a number of tumor cell survival pathways such as cell proliferation, apoptosis, tumor cell invasion and metastasis, and angiogenesis. However, the effects of these respective synthases differ considerably with respect to the pathways described. While prostacyclin synthase is generally believed to be anti-tumor, a pro-carcinogenic role for thromboxane synthase has been demonstrated in a variety of cancers. The balance of oppositely-acting COX-derived prostanoids influences many processes throughout the body, such as blood pressure regulation, clotting, and inflammation. The PGI2/TXA2 ratio is of particular interest in-vivo, with the corresponding synthases shown to be differentially regulated in a variety of disease states. Pharmacological inhibition of thromboxane synthase has been shown to significantly inhibit tumor cell growth, invasion, metastasis and angiogenesis in a range of experimental models. In direct contrast, prostacyclin synthase overexpression has been shown to be chemopreventive in a murine model of the disease, suggesting that the expression and activity of this enzyme may protect against tumor development. In this review, we discuss the aberrant expression and known functions of both prostacyclin synthase and thromboxane synthase in cancer. We discuss the effects of these enzymes on a range of tumor cell survival pathways, such as tumor cell proliferation, induction of apoptosis, invasion and metastasis, and tumor cell angiogenesis. As downstream signaling pathways of these enzymes have also been implicated in cancer states, we examine the role of downstream effectors of PGIS and TXS activity in tumor growth and progression. Finally, we discuss current therapeutic strategies aimed at targeting these enzymes for the prevention/treatment of cancer. © 2010 Elsevier B.V. All rights reserved.

The evolution and diversification of Dicers in plants

Most multicellular organisms regulate developmental transitions by microRNAs, which are generated by an enzyme, Dicer. Insects and fungi have two Dicer-like genes, and many animals have only one, yet the plant, Arabidopsis, has four. Examining the poplar and rice genomes revealed that they contain five and six Dicer-like genes, respectively. Analysis of these genes suggests that plants require a basic set of four Dicer types which were present before the divergence of mono- and dicotyledonous plants (∼200 million years ago), but after the divergence of plants from green algae. A fifth type of Dicer seems to have evolved in monocots. © 2006 Federation of European Biochemical Societies.

The optimal duration and delay of first aid treatment for deep partial thickness burn injuries

Using our porcine model of deep dermal partial thickness burn injury, various durations (10min, 20min, 30min or 1h) and delays (immediate, 10min, 1h, 3h) of 15 degrees C running water first aid were applied to burns and compared to untreated controls. The subdermal temperatures were monitored during the treatment and wounds observed weekly for 6 weeks, for re-epithelialisation, wound surface area and cosmetic appearance. At 6 weeks after the burn, tissue biopsies were taken of the scar for histological analysis. Results showed that immediate application of cold running water for 20min duration is associated with an improvement in re-epithelialisation over the first 2 weeks post-burn and decreased scar tissue at 6 weeks. First aid application of cold water for as little as 10min duration or up to 1h delay still provides benefit.

Animal stories : flash flood 2011

Flash flood disasters happen suddenly. The Toowoomba Lockyer Valley flash flood in January 2011 was not forecast by the Bureau of Meteorology until after it had occurred. Domestic and wild animals gave the first warning of the disaster in the days leading up to the event and large animals gave warnings on the morning of the disaster. Twenty-three people, including 5 children in the disaster zone died. More than 500 people were listed as missing. Some of those who died, perished because they stayed in the disaster zone to look after their animals while other members of their family escaped to safety. Some people who were in danger refused to be rescued because they could not take their pets with them. During a year spent recording accounts of the survivors of the disaster, animals were often mentioned by survivors. Despite the obvious perils, people risked their lives to save their animals; people saw animals try to save each other; animals rescued people; people rescued animals; animals survived where people died; animals were used to find human victims in the weeks after the disaster; and animals died. The stories of the flood present challenges for pet owners, farmers, counter disaster planners, weather forecasters and emergency responders in preparing for disasters, responding to them and recovering after them.

Genome analysis reveals insights into physiology and longevity of the Brandt’s bat Myotis brandtii

Bats account for one-fifth of mammalian species, are the only mammals with powered flight, and are among the few animals that echolocate. The insect-eating Brandt’s bat (Myotis brandtii) is the longest-lived bat species known to date (lifespan exceeds 40 years) and, at 4–8 g adult body weight, is the most extreme mammal with regard to disparity between body mass and longevity. Here we report sequencing and analysis of the Brandt’s bat genome and transcriptome, which suggest adaptations consistent with echolocation and hibernation, as well as altered metabolism, reproduction and visual function. Unique sequence changes in growth hormone and insulin-like growth factor 1 receptors are also observed. The data suggest that an altered growth hormone/insulin-like growth factor 1 axis, which may be common to other long-lived bat species, together with adaptations such as hibernation and low reproductive rate, contribute to the exceptional lifespan of the Brandt’s bat.

Antisense-mediated suppression of hyaluronan synthase 2 inhibits the tumorigenesis and progression of breast cancer

The progression of several cancers is correlated with the increased synthesis of the glycosaminoglycan, hyaluronan. Hyaluronan is synthesized at the plasma membrane by various isoforms of hyaluronan synthases (HAS). The importance of HAS2 expression in highly invasive breast cancer was characterized by the antisense inhibition of HAS2 (ASHAS2). The effect of HAS2 inhibition on cell proliferation, migration, hyaluronan metabolism, and receptor status was characterized in vitro, whereas the effect on tumorigenicity and metastasis was established in vivo. HAS2 inhibition resulted in a 24-hour lag in proliferation that was concomitant to transient arrest of 79% of the cell population in G 0-G1. Inhibition of HAS2 did not alter the expression of the other HAS isoforms, whereas hyaluronidase (HYAL2) and the hyaluronan receptor, CD44, were significantly down-regulated. ASHAS2 cells accumulated greater amounts of high molecular weight hyaluronan (>10,000 kDa) in the culture medium, whereas mock and parental cells liberated less hyaluronan of three distinct molecular weights (100, 400, and 3,000 kDa). The inhibition of HAS2 in the highly invasive MDA-MB-231 breast cancer cell line inhibited the initiation and progression of primary and secondary tumor formation following s.c. and intracardiac inoculation into nude mice, whereas controls readily established both primary and secondary tumors. The lack of primary and secondary tumor formation was manifested by increased survival times where ASHAS2 animals survived 172% longer than the control animals. Collectively, these unique results strongly implicate the central role of HAS2 in the initiation and progression of breast cancer, potentially highlighting the codependency between HAS2, CD44, and HYAL2 expression. ©2005 American Association for Cancer Research.

A dynamic in vivo model of epithelial-to-mesenchymal transitions in circulating tumor cells and metastases of breast cancer

Epithelial-to-mesenchymal transition (EMT) processes endow epithelial cells with enhanced migratory/invasive properties and are therefore likely to contribute to tumor invasion and metastatic spread. Because of the difficulty in following EMT processes in human tumors, we have developed and characterized an animal model with transplantable human breast tumor cells (MDA-MB-468) uniquely showing spontaneous EMT events to occur. Using vimentin as a marker of EMT, heterogeneity was revealed in the primary MDA-MB-468 xenografts with vimentin-negative and vimentin-positive areas, as also observed on clinical human invasive breast tumor specimens. Reverse transcriptase-PCR after microdissection of these populations from the xenografts revealed EMT traits in the vimentin-positive zones characterized by enhanced 'mesenchymal gene' expression (Snail, Slug and fibroblast-specific protein-1) and diminished expression of epithelial molecules (E-cadherin, ZO-3 and JAM-A). Circulating tumor cells (CTCs) were detected in the blood as soon as 8 days after s.c. injection, and lung metastases developed in all animals injected as examined by in vivo imaging analyses and histology. High levels of vimentin RNA were detected in CTCs by reverse transcriptase-quantitative PCR as well as, to a lesser extent, Snail and Slug RNA. Von Willebrand Factor/vimentin double immunostainings further showed that tumor cells in vascular tumoral emboli all expressed vimentin. Tumoral emboli in the lungs also expressed vimentin whereas macrometastases displayed heterogenous vimentin expression, as seen in the primary xenografts. In conclusion, our data uniquely demonstrate in an in vivo context that EMT occurs in the primary tumors, and associates with an enhanced ability to intravasate and generate CTCs. They further suggest that mesenchymal-to-epithelial phenomena occur in secondary organs, facilitating the metastatic growth.

An investigation of functional diversity of endogenous cellulase and expression of other digestive enzyme genes in freshwater crayfish (Cherax) species

The project evaluated potential of soluble cellulose as a cheap feed ingredient for major farmed Australian freshwater crayfish species testing their growth performance, digestive enzyme activity and digestive enzyme gene expression patterns. Test animals showed an innate capacity to utilise a range of carbohydrate sources including complex structural polysaccharides. Results suggest that more plant-derived ingredient can be incorporated in formulated low-cost feeds for the culture industry.

Genotoxicity of inorganic lead salts and disturbance of microtubule function

Lead compounds are known genotoxicants, principally affecting the integrity of chromosomes. Lead chloride and lead acetate induced concentration-dependent increases in micronucleus frequency in V79 cells, starting at 1.1 μM lead chloride and 0.05 μM lead acetate. The difference between the lead salts, which was expected based on their relative abilities to form complex acetato-cations, was confirmed in an independent experiment. CREST analyses of the micronuclei verified that lead chloride and acetate were predominantly aneugenic (CREST-positive response), which was consistent with the morphology of the micronuclei (larger micronuclei, compared with micronuclei induced by a clastogenic mechanism). The effects of high concentrations of lead salts on the microtubule network of V79 cells were also examined using immunofluorescence staining. The dose effects of these responses were consistent with the cytotoxicity of lead(II), as visualized in the neutral-red uptake assay. In a cell-free system, 20-60 μM lead salts inhibited tubulin assembly dose-dependently. The no-observed-effect concentration of lead(II) in this assay was 10 μM. This inhibitory effect was interpreted as a shift of the assembly/disassembly steady-state toward disassembly, e.g., by reducing the concentration of assembly-competent tubulin dimers. The effects of lead salts on microtubule-associated motor-protein functions were studied using a kinesin-gliding assay that mimics intracellular transport processes in vitro by quantifying the movement of paclitaxel-stabilized microtubules across a kinesin-coated glass surface. There was a dose-dependent effect of lead nitrate on microtubule motility. Lead nitrate affected the gliding velocities of microtubules starting at concentrations above 10 μM and reached half-maximal inhibition of motility at about 50 μM. The processes reported here point to relevant interactions of lead with tubulin and kinesin at low dose levels.

Nephrotoxicity and nephrocarcinogenicity of dinitrotoluene : new aspects to be considered

Technical dinitrotoluene (DNT) is a mixture of 2,4- and 2,6-DNT. In humans, industrial or environmental exposure can occur orally, by inhalation, or by skin contact. The classification of DNT as an 'animal carcinogen' is based on the formation of malignant tumors in kidneys, liver, and mammary glands of rats and mice. Clear signs of toxic nephropathy were found in rats dosed with DNT, and the concept was derived of an interrelation between renal toxicity and carcinogenicity. Recent data point to the carcinogenicity of DNT on the urinary tract of exposed humans. Between 1984 and 1997, 6 cases of urothelial cancer and 14 cases of renal cell cancer were diagnosed in a group of 500 underground mining workers in the copper mining industry of the former GDR and having high exposures to explosives containing technical DNT. The incidences of both urothelial and renal cell tumors in this group were 4.5 and 14.3 times higher, respectively, than anticipated on the basis of the cancer registers of the GDR. The genotyping of all identified tumor patients for the polymorphic enzymes NAT2, GSTM1, and GSTT1 identified the urothelial tumor cases as exclusively 'slow acetylates'. A group of 161 miners highly exposed to DNT was investigated for signs of subclinical renal damage. The exposures were categorized semi-quantitatively into 'low', 'medium', 'high', and 'very high'. A straight dose-dependence of the excretion of urinary biomarker proteins with the ranking of exposure was seen. Biomarker excretion (alpha1-microglobulin, glutathione S-transferases alpha and pi) indicated that DNT-induced damage was directed toward the tubular system. New data on DNT-exposed humans appear consistent with the concept of cancer initiation by DNT isomers and the subsequent promotion of renal carcinogenesis by selective damage to the proximal tubule. The differential pathways of metabolic activation of DNT appear to apply to the proximal tubule of the kidney and to the urothelium of the renal pelvis and lower urinary tract as target tissues of carcinogenicity.

Disturbed microtubule function and induction of micronuclei by chelate complexes of mercury(II)

Interactions of mercury(II) with the microtubule network of cells may lead to genotoxicity. Complexation of mercury(II) with EDTA is currently being discussed for its employment in detoxification processes of polluted sites. This prompted us to re-evaluate the effects of such complexing agents on certain aspects of mercury toxicity, by examining the influences of mercury(II) complexes on tubulin assembly and kinesin-driven motility of microtubules. The genotoxic effects were studied using the micronucleus assay in V79 Chinese hamster fibroblasts. Mercury(II) complexes with EDTA and related chelators interfered dose-dependently with tubulin assembly and microtubule motility in vitro. The no-effect-concentration for assembly inhibition was 1 μM of complexed Hg(II), and for inhibition of motility it was 0.05 μM, respectively. These findings are supported on the genotoxicity level by the results of the micronucleus assay, with micronuclei being induced dose-dependently starting at concentrations of about 0.05 μM of complexed Hg(II). Generally, the no-effect-concentrations for complexed mercury(II) found in the cell-free systems and in cellular assays (including the micronucleus test) were identical with or similar to results for mercury tested in the absence of chelators. This indicates that mercury(II) has a much higher affinity to sulfhydryls of cytoskeletal proteins than to this type of complexing agents. Therefore, the suitability of EDTA and related compounds for remediation of environmental mercury contamination or for other detoxification purposes involving mercury has to be questioned.

Comparison of GST theta activity in liver and kidney of four species

Glutathione transferases (GSTs) catalyzing the conjugation of glutathione with electrophilic substrates are important enzymes in the metabolism of xenobiotics. Several isozymes exhibit polymorphisms in humans. The two deletion polymorphisms of hGSTM1 and hGSTT1 result in total loss of enzyme activity in homozygous null genotype (GSTM1*0 and GSTT1*0 respectively) individuals (Seidegård et al. 1988; Pemble et al. 1994). Individuals that are heterozygous for hGSTT1 show distinctly lower enzyme activities than individuals carrying two functional alleles of hGSTT1 (Wiebel et al. 1996). A similar effect is conceivable for the hGSTM1 polymorphism but has not been verified so far.

Qld floods inquest : stories of courage, sacrifice in emotional replay

"The last acts of courage and sacrifice by parents desperately trying to save their children as a deadly flash flood ripped through south-east Queensland in January fell like repeated emotional hammer-blows on survivors in the public gallery of the Brisbane Coroners Court yesterday. The speed with which the disaster tore lives and homes apart on January 10 was replicated by the speed at which police summarised the circumstances of the deaths for the coroner. After months of investigation by hundreds of police, the final desperate minutes of 14 people’s lives were summed up for the court before the morning tea break, in as little as three minutes each."