Perceptions and expectations for learning and development for older workers within Queensland local government councils : a case study

Current literature warns organisations about a global ageing phenomenon. Workplace ageing is causing a diminishing work pool which has consequences for a sustainable workforce in the future. This phenomenon continues to impact on local government councils in Australia. Australia has one of the world’s most rapidly ageing populations, and there is evidence that Australian local government councils are already resulting in an unsustainable workforce. Consequently, this research program investigated the role of older workers in the Queensland local government workplace in enabling them to extend their working lives towards transitional employment and a sustainable workforce in the future. Transitional Employment is intended as a strategy for enabling individuals to have greater control over their employment options and their employability during the period leading to their final exit from the workforce. There was no evidence of corporate support for older workers in Queensland local government councils other than tokenistic government campaigns encouraging organisations to "better value their older workers". (Queensland Government, 2007d, p.6). TE is investigated as a possible intervention for older workers in the future. The international and national literature review reflected a range of matters impacting on current older workers in the workforce and barriers preventing them from accessing services towards extending their employment beyond the traditional retirement age (60 years) as defined by the Australian Government; an age when individuals can access their superannuation. Learning and development services were identified as one of those barriers. There was little evidence of investment in or consistent approaches to supporting older workers by organisations. Learning and development services appeared at best to be ad hoc, reactive to corporate productivity and outputs with little recognition of the ageing phenomenon (OECD, 2006, p.23) and looming skills and labour shortages (ALGA, 2006, p. 19). Themes from the literature review led to the establishment of three key research questions: 1. What are the current local government workforce issues impacting on skills and labour retention? 2. What are perceptions about the current workplace environment? And, 3. What are the expectations about learning and development towards extending employability of older workers within the local government sector? The research questions were explored by utilising three qualitative empirical studies, using some numerical data for reporting and comparative analysis. Empirical Study One investigated common themes for accessing transitional employment and comprised two phases. A literature review and Study One data analysis enabled the construction of an initial Transitional Employment Model which includes most frequent themes. Empirical Study Two comprised focus groups to further consider those themes. This led to identification of issues impacting the most on access to learning and development by older workers and towards a revised TEM. Findings presented majority support for transitional employment as a strategy for supporting older workers to work beyond their traditional retirement age. Those findings are presented as significant issues impacting on access to transitional employment within the final 3-dimensionsal TEM. The model is intended as a guide for responding to an ageing workforce by local government councils in the future. This study argued for increased and improved corporate support, particularly for learning and development services for older workers. Such support will enable older workers to maintain their employability and extend their working lives; a sustainable workforce in the future.

Are we missing opportunities? Understanding health behaviours associated with overweight in pregnancy

While maternal obesity, excess pregnancy weight gain and lifestyle behaviours are associated with future overweight for both mothers and babies, there is limited research on how best to intervene. An evidence base that identifies behavioural influences is crucial to the development of effective interventions. This thesis aims to gain an understanding of maternal behavioural outcomes of healthy eating, physical activity and gestational weight gain (GWG), the psychosocial influences on these and to examine differences according to pre-pregnancy weight status. The New Beginnings Healthy Mothers and Babies Study was a prospective observational study using the PRECEDE-PROCEED model of health promotion planning as a framework. A consecutive sample of 715 women was recruited. Height and weight were measured and women completed questionnaires at approximately 16 and 36 weeks gestation. This thesis presents three chapters of original research across four study domains. While healthy eating was widely regarded as important during pregnancy and had become more so, there was more variability in attitudes towards physical activity. Ninety-two percent of participants achieved the maximum knowledge score relating to the influence of nutrition on pregnancy. However, 8% and 36% respectively knew how many serves of fruit and vegetables should be consumed daily. Six percent of participants met the recommendations for fruit consumption, 4% achieved the recommended vegetable intake and 44% achieved sufficient physical activity. There were few differences between healthy and overweight women for measures of physical activity and healthy eating. Many predisposing, reinforcing and enabling factors with a positive influence on health behaviours were lower in women commencing pregnancy overweight and those factors with a negative influence on health behaviours were higher when compared to healthy weight women. Some of these antecedents to health behaviours that were different according to prepregnancy weight status were associated with diet quality and physical activity. While self efficacy was consistently associated with diet quality and physical activity for both weight groups, other associations between specific predisposing, reinforcing and enabling factors differed with behaviour and weight status group. These results highlight the complexity of supporting behaviour change in a one-size-fits-all approach. Sixty-four percent of participants gained weight outside of recommendations. Compared to healthy weight women, those women who were already overweight at the beginning of pregnancy were more likely to gain too much weight (30% vs 56%, p<0.001). Only 35% of participants reported their correct recommended weight gain. Excess GWG was associated with few predisposing factors, however, these were not consistent between prepregnancy weight status groups. Less than 50% of women reported sometimes/usually/always receiving advice from health professionals relating to healthy eating, physical activity or GWG. These results indicate that there are opportunities to improve the advice and support provided by health care professionals in the antenatal period. Evidence from this PhD research suggests that there is a need for effective prevention and management of excess weight in pregnancy. Effective management of this problem is likely to require a multidisciplinary approach with multi-level strategies. Importantly, the strategies may need to be tailored according to pre-pregnancy weight status. Collectively, the evidence derived from this thesis suggests that opportunities to support healthy lifestyles and prevent future overweight are being missed during pregnancy.

Physical performance profile of sub-elite juvenile Gaelic Games players and the prevalence of a Relative Age Effect (RAE)

Gaelic Games are the indigenous sports played in Ireland, the most popular being Gaelic football and hurling. The games are contact sports and the physical demands are thought to be similar to those of Australian Rules football, rugby union, rugby league, field hockey, and lacrosse (Delahunt et al., 2011). The difference in chronological age between children in a single age group is known as relative age and its consequences as the RAE, whereby younger players are disadvantaged (Del Campo et al., 2010). The purpose of this study was to describe the physical and performance profile of sub-elite juvenile Gaelic Games players and to establish if a RAE is present in this cohort and any influence physiological moderator variables may have on this. Following receipt of ethical approval (EHSREC11-45), six sub-elite county development squads (Under-14/15/16 age groups, male, n=115) volunteered to partake in the study. Anthropometric data including skin folds and girths were collected. A number of field tests of physical performance including 5 and 20m speed, vertical and broad jump distance, and an estimate of VO2max were carried out. Descriptive data are presented as Mean SD. Juvenile sub-elite Gaelic Games players aged 14.53 0.82 y were 172.87 7.63 cm tall, had a mass of 64.74 11.06 kg, a BMI of 21.57 2.82 kg.m-2 and 9.22 4.78 % body fat. Flexibility, measured by sit and reach was 33.62 6.86 cm and lower limb power measured by vertical and broad jump were 42.19 5.73 and 191.16 25.26 cm, respectively. Participant time to complete 5m, 20m and an agility test (T-Test) was 1.12 0.07, 3.31 0.30 and 9.31 0.55 s respectively. Participant’s estimated VO2max was 48.23 5.05 ml.kg.min-1. Chi-Square analysis of birth month by quartile (Q1 = January-March) revealed that a RAE was present in this cohort, whereby an over-representation of players born in Q1 compared with Q2, Q3 and Q4 was evident (2 = 14.078, df = 3, p = 0.003). Kruskal-Wallis analysis of the data revealed no significant difference in any of the performance parameters based on quartile of birth (Alpha level = 0.05).This study provides a physical performance profile of juvenile sub-elite Gaelic Games players, comparable with those of other sports such as soccer and rugby. This novel data can inform us of the physical requirements of the sport. The evidence of a RAE is similar to that observed in other contact sports such as soccer and rugby league (Carling et al, 2009; Till et al, 2010). Although a RAE exists in this cohort, this cannot be explained by any physical/physiological moderator variables. Carling C et al. (2009). Scandinavian Journal of Medicine and Science in Sport 19, 3-9. Delahunt E et al. (2011). Journal of Athletic Training 46, 241-5. Del Campo DG et al. (2010). Journal of Sport Science and Medicine 9, 190-198. Delorme N et al. (2010). European Journal of Sport Science 10, 91-96. Till K et al. (2010). Scandinavian Journal of Medicine and Science in Sports 20, 320-329.

Differences in Epidural and Analgesic Use in Patients with Apparent Stage I Endometrial Cancer treated by open versus laparoscopic surgery: results from the randomised LACE trial

Objectives: We compared post-operative analgesic requirements between women with early stage endometrial cancer treated by total abdominal hysterectomy (TAH) or total laparoscopic hysterectomy (TLH). Methods: 760 patients with apparent stage I endometrial cancer were treated in the international, multicentre, prospective randomised trial (LACE) by TAH (n=353) or TLH (n=407) (2005-2010). Epidural, opioid and non-opioid analgesic requirements were collected until ten months after surgery. Results: Baseline demographics and analgesic use were comparable between treatment arms. TAH patients were more likely to receive epidural analgesia than TLH patients (33% vs 0.5%, p<0.001) during the early postoperative phase. Although opioid use was comparable in the TAH vs TLH groups during postoperative 0-2 days (99.7% vs 98.5%, p 0.09), a significantly higher proportion of TAH patients required opioids 3-5 days (70% vs 22%, p<0.0001), 6-14 days (35% vs 15%, p<0.0001), and 15-60 days (15% vs 9%, p 0.02) post-surgery. Mean pain scores were significantly higher in the TAH versus TLH group one (2.48 vs 1.62, p<0.0001) and four weeks (0.89 vs 0.63, p 0.01) following surgery. Conclusion: Treatment of early stage endometrial cancer with TLH is associated with less frequent use of epidural, lower post-operative opioid requirements and better pain scores than TAH.

The effect of hydroxyl groups and surface area of hematite derived from annealing goethite for phosphate removal

Synthetic goethite and thermally treated goethite at different temperatures were used to remove phosphate from sewage. The effect of annealing temperature on phosphate removal over time was investigated. X-ray diffraction(XRD), transmission electron microscopy (TEM), N2 adsorption and desorption (BET), and infrared emission spectrum (FT-IES) were utilized to characterize the phase, morphology, specific surface area, pore distribution, and the surface groups of samples. The results show that annealed products of goethite at temperatures over 250 °C are hematite with the similar morphology as the original goethite with different hydroxyl groups and surface area. Increasing temperature causes the decrease in hydroxyl groups, consequential increase in surface area at first and then experiences a decrease (14.8–110.4–12.6 m2/g) and the subsequent formation of nanoscale pores. The variation rate of hydroxyl groups and surface area based on FT-IES and BET, respectively, are used to evaluate the effect of annealing temperature on phosphate removal. By using all of the characterization techniques, it is concluded that the changes of phosphate removal basically result from the total variation rate between hydroxyl groups and surface area.

Nutritional status of Ugandan women living with HIV/AIDS : anthropometry and body composition assessment

Human immunodeficiency virus (HIV) that leads to acquired immune deficiency syndrome (AIDs) reduces immune function, resulting in opportunistic infections and later death. Use of antiretroviral therapy (ART) increases chances of survival, however, with some concerns regarding fat re-distribution (lipodystrophy) which may encompass subcutaneous fat loss (lipoatrophy) and/or fat accumulation (lipohypertrophy), in the same individual. This problem has been linked to Antiretroviral drugs (ARVs), majorly, in the class of protease inhibitors (PIs), in addition to older age and being female. An additional concern is that the problem exists together with the metabolic syndrome, even when nutritional status/ body composition, and lipodystrophy/metabolic syndrome are unclear in Uganda where the use of ARVs is on the increase. In line with the literature, the overall aim of the study was to assess physical characteristics of HIV-infected patients using a comprehensive anthropometric protocol and to predict body composition based on these measurements and other standardised techniques. The other aim was to establish the existence of lipodystrophy, the metabolic syndrome, andassociated risk factors. Thus, three studies were conducted on 211 (88 ART-naïve) HIV-infected, 15-49 year-old women, using a cross-sectional approach, together with a qualitative study of secondary information on patient HIV and medication status. In addition, face-to-face interviews were used to extract information concerning morphological experiences and life style. The study revealed that participants were on average 34.1±7.65 years old, had lived 4.63±4.78 years with HIV infection and had spent 2.8±1.9 years receiving ARVs. Only 8.1% of participants were receiving PIs and 26% of those receiving ART had ever changed drug regimen, 15.5% of whom changed drugs due to lipodystrophy. Study 1 hypothesised that the mean nutritional status and predicted percent body fat values of study participants was within acceptable ranges; different for participants receiving ARVs and the HIV-infected ART-naïve participants and that percent body fat estimated by anthropometric measures (BMI and skinfold thickness) and the BIA technique was not different from that predicted by the deuterium oxide dilution technique. Using the Body Mass Index (BMI), 7.1% of patients were underweight (<18.5 kg/m2) and 46.4% were overweight/obese (≥25.0 kg/m2). Based on waist circumference (WC), approximately 40% of the cohort was characterized as centrally obese. Moreover, the deuterium dilution technique showed that there was no between-group difference in the total body water (TBW), fat mass (FM) and fat-free mass (FFM). However, the technique was the only approach to predict a between-group difference in percent body fat (p = .045), but, with a very small effect (0.021). Older age (β = 0.430, se = 0.089, p = .000), time spent receiving ARVs (β = 0.972, se = 0.089, p = .006), time with the infection (β = 0.551, se = 0.089, p = .000) and receiving ARVs (β = 2.940, se = 1.441, p = .043) were independently associated with percent body fat. Older age was the greatest single predictor of body fat. Furthermore, BMI gave better information than weight alone could; in that, mean percentage body fat per unit BMI (N = 192) was significantly higher in patients receiving treatment (1.11±0.31) vs. the exposed group (0.99±0.38, p = .025). For the assessment of obesity, percent fat measures did not greatly alter the accuracy of BMI as a measure for classifying individuals into the broad categories of underweight, normal and overweight. Briefly, Study 1 revealed that there were more overweight/obese participants than in the general Ugandan population, the problem was associated with ART status and that BMI broader classification categories were maintained when compared with the gold standard technique. Study 2 hypothesized that the presence of lipodystrophy in participants receiving ARVs was not different from that of HIV-infected ART-naïve participants. Results showed that 112 (53.1%) patients had experienced at least one morphological alteration including lipohypertrophy (7.6%), lipoatrophy (10.9%), and mixed alterations (34.6%). The majority of these subjects (90%) were receiving ARVs; in fact, all patients receiving PIs reported lipodystrophy. Period spent receiving ARVs (t209 = 6.739, p = .000), being on ART (χ2 = 94.482, p = .000), receiving PIs (Fisher’s exact χ2 = 113.591, p = .000), recent T4 count (CD4 counts) (t207 = 3.694, p = .000), time with HIV (t125 = 1.915, p = .045), as well as older age (t209 = 2.013, p = .045) were independently associated with lipodystrophy. Receiving ARVs was the greatest predictor of lipodystrophy (p = .000). In other analysis, aside from skinfolds at the subscapular (p = .004), there were no differences with the rest of the skinfold sites and the circumferences between participants with lipodystrophy and those without the problem. Similarly, there was no difference in Waist: Hip ratio (WHR) (p = .186) and Waist: Height ratio (WHtR) (p = .257) among participants with lipodystrophy and those without the problem. Further examination showed that none of the 4.1% patients receiving stavudine (d4T) did experience lipoatrophy. However, 17.9% of patients receiving EFV, a non-nucleoside reverse transcriptase inhibitor (NNRTI) had lipoatrophy. Study 2 findings showed that presence of lipodystrophy in participants receiving ARVs was in fact far higher than that of HIV-infected ART-naïve participants. A final hypothesis was that the prevalence of the metabolic syndrome in participants receiving ARVs was not different from that of HIV-infected ART-naïve participants. Moreover, data showed that many patients (69.2%) lived with at least one feature of the metabolic syndrome based on International Diabetic Federation (IDF, 2006) definition. However, there was no single anthropometric predictor of components of the syndrome, thus, the best anthropometric predictor varied as the component varied. The metabolic syndrome was diagnosed in 15.2% of the subjects, lower than commonly reported in this population, and was similar between the medicated and the exposed groups (χ 21 = 0.018, p = .893). Moreover, the syndrome was associated with older age (p = .031) and percent body fat (p = .012). In addition, participants with the syndrome were heavier according to BMI (p = .000), larger at the waist (p = .000) and abdomen (p = .000), and were at central obesity risk even when hip circumference (p = .000) and height (p = .000) were accounted for. In spite of those associations, results showed that the period with disease (p = .13), CD4 counts (p = .836), receiving ART (p = .442) or PIs (p = .678) were not associated with the metabolic syndrome. While the prevalence of the syndrome was highest amongst the older, larger and fatter participants, WC was the best predictor of the metabolic syndrome (p = .001). Another novel finding was that participants with the metabolic syndrome had greater arm muscle circumference (AMC) (p = .000) and arm muscle area (AMA) (p = .000), but the former was most influential. Accordingly, the easiest and cheapest indicator to assess risk in this study sample was WC should routine laboratory services not be feasible. In addition, the final study illustrated that the prevalence of the metabolic syndrome in participants receiving ARVs was not different from that of HIV-infected ART-naïve participants.

The use of navigation to achieve soft tissue balance in total knee arthroplasty : a randomised clinical study

Background: Achieving soft tissue balance is an operative goal in total knee arthroplasty. This randomised, prospective study compared computer navigation to conventional techniques in achieving soft tissue balance. Methods: Forty one consecutive knee arthroplasties were randomised to either a non-navigated or navigated group. In the non-navigated group, balancing was carried out using surgeon judgement. In the navigated group, balancing was carried out using navigation software. In both groups, the navigation software was used as a measuring tool. Results: Balancing of the mediolateral extension gap was superior in the navigation group (p=0.001). No significant difference was found between the two groups in balancing the mediolateral flexion gap or in achieving equal flexion and extension gaps. Conclusions: Computer navigation offered little advantage over experienced surgeon judgement in achieving soft tissue balance in knee replacement. However, the method employed in the navigated group did provide a reproducible and objective assessment of flexion and extension gaps and may therefore benefit surgeons in training.

“We eat more than kangaroo tail or dugong you know…” : recent indigenous Australian cookbooks

This paper focuses on a series of cookbooks published by Indigenous Australian groups. These cookbooks are typically produced with government funding, and are developed by nutritionists, dieticians, and health workers in consultation with local communities. They are designed to teach Indigenous Australians to cook healthy, nutritious, low-cost meals. In this paper, Fredericks and Anderson identify the value of these cookbooks as low-cost, public health interventions. However, they note that their value as health interventions has not been tested. Fredericks and Anderson question the value of these cookbooks within the broader context of the health disadvantage faced by Indigenous Australians. They argue that the cookbooks are developed from a Western perspective of health and nutrition that fails to recognise the value of traditional Indigenous foodways. They suggest that incorporating more Indigenous food knowledge and food-related traditions into cookbooks may be one way of improving health among Indigenous peoples and revitalising Indigenous knowledge.

Insights into the mechanism of the reaction between ttrachloro-p-bnzoquinone and hydrogen peroxide and their implications in the catalytic role of water molecules in producing the hydroxyl radial

Detailed mechanisms for the formation of hydroxyl or alkoxyl radicals in the reactions between tetrachloro-p-benzoquinone (TCBQ) and organic hydroperoxides are crucial for better understanding the potential carcinogenicity of polyhalogenated quinones. Herein, the mechanism of the reaction between TCBQ and H2O2 has been systematically investigated at the B3LYP/6-311++G** level of theory in the presence of different numbers of water molecules. We report that the whole reaction can easily take place with the assistance of explicit water molecules. Namely, an initial intermediate is formed first. After that, a nucleophilic attack of H2O2 onto TCBQ occurs, which results in the formation of a second intermediate that contains an OOH group. Subsequently, this second intermediate decomposes homolytically through cleavage of the O-O bond to produce a hydroxyl radical. Energy analyses suggest that the nucleophilic attack is the rate-determining step in the whole reaction. The participation of explicit water molecules promotes the reaction significantly, which can be used to explain the experimental phenomena. In addition, the effects of F, Br, and CH3 substituents on this reaction have also been studied.

Bridging the gap: Wellness differences between high and low SES Australian adolescents

Aims Wellness assessments can determine adolescent lifestyle behaviors. A better understanding of wellness differences between high and low SES adolescents could assist policy makers to develop improved strategies to bridge the gap between these two groups. The aim of this investigation was to explore wellness differences between high and low SES adolescents. Methods In total, 241 (125 high and 116 low SES) adolescents completed the 5-Factor Wellness Inventory (5F-Wel). The 5F-Wel comprises 97 items contributing to 17 subscales, 5 dimensions, 4 contexts, total wellness, and a life satisfaction index, with scores ranging from 0-100. Independent sample t-tests were performed with Levene’s test of equality for variances, which checked the assumption of homogeneity of variances. Results Overall, 117 (94%) and 112 (97 %) high and low SES participants had complete data and were included in the analysis. The high SES group scored higher for total wellness (M = 81.09, SE = .61) than the low SES group (M = 75.73, SE = .99). This difference was significant t (186) = 4.635, p < .05, with a medium effect size r = .32. The high SES group scored higher on 23 of 27 scales (21 scales, p < .05), while the low SES group scored higher on the remaining 3 scales (all non-significant). Conclusion These results contribute empirical data to the body of literature, indicating a large wellness discrepancy between high and low SES youth. Deficient areas can be targeted by policymakers to assist in bridging the gap between these groups.

Organized crime in Oceania

Oceania has a relatively low level of crime prevalence yet in the smaller and under-developed PICs we have shown that transnational crime has become increasingly common. A risk contained but potentially dangerous if state failure or fragility undermines law enforcement capacities. We predict that as the pace of globalization quickens and the demand for raw materials and resources grows some parts of the Pacific will be prone to criminal enterprises run by both indigenous and foreign crime groups. Australia and New Zealand will remain attractors of illicit goods notably ATS but will in turn be source countries for diminishing fish stock such as beche de mere and abalone as well forest timber. Finally the role of states such as Australia and New Zealand in helping to maintain law enforcement capacities throughout the region will be crucial if organized crime in Oceania is to be kept in check while demand for illicit resources grow.

Transnational organized crime in Oceania

Oceania has a relatively low level of crime prevalence yet in the smaller and under-developed PICs we have shown that transnational crime has become increasingly common. A risk contained but potentially dangerous if state failure or fragility undermines law enforcement capacities. We predict that as the pace of globalization quickens and the demand for raw materials and resources grows some parts of the Pacific will be prone to criminal enterprises run by both indigenous and foreign crime groups. Australia and New Zealand will remain attractors of illicit goods notably ATS but will in turn be source countries for diminishing fish stock such as beche de mere and abalone as well forest timber. Finally the role of states such as Australia and New Zealand in helping to maintain law enforcement capacities throughout the region will be crucial if organized crime in Oceania is to be kept in check while demand for illicit resources grow.

Development of an integrated metabolomic profiling approach for infectious diseases research

Metabolomic profiling offers direct insights into the chemical environment and metabolic pathway activities at sites of human disease. During infection, this environment may receive important contributions from both host and pathogen. Here we apply an untargeted metabolomics approach to identify compounds associated with an E. coli urinary tract infection population. Correlative and structural data from minimally processed samples were obtained using an optimized LC-MS platform capable of resolving ~2300 molecular features. Principal component analysis readily distinguished patient groups and multiple supervised chemometric analyses resolved robust metabolomic shifts between groups. These analyses revealed nine compounds whose provisional structures suggest candidate infection-associated endocrine, catabolic, and lipid pathways. Several of these metabolite signatures may derive from microbial processing of host metabolites. Overall, this study highlights the ability of metabolomic approaches to directly identify compounds encountered by, and produced from, bacterial pathogens within human hosts.

Molecular characterisation and expression analysis of interferon gamma in response to natural chlamydia infection in the koala, phascolarctos cinereus

Interferon gamma (IFNγ) is a key Th1 cytokine, with a principal role in the immune response against intracellular organisms such as Chlamydia. Along with being responsible for significant morbidity in human populations, Chlamydia is also responsible for wide spread infection and disease in many animal hosts, with reports that many Australian koala subpopulations are endemically infected. An understanding of the role played by IFNγ in koala chlamydial diseases is important for the establishment of better prophylactic and therapeutic approaches against chlamydial infection in this host. A limited number of IFNγ sequences have been published from marsupials and no immune reagents to measure expression have been developed. Through preliminary analysis of the koala transcriptome, we have identified the full coding sequence of the koala IFNγ gene. Transcripts were identified in spleen and lymph node tissue samples. Phylogenetic analysis demonstrated that koala IFNγ is closely related to other marsupial IFNγ sequences and more distantly related to eutherian mammals. To begin to characterise the role of this important cytokine in the koala's response to chlamydial infection, we developed a quantitative real time PCR assay and applied it to a small cohort of koalas with and without active chlamydial disease, revealing significant differences in expression patterns between the groups. Description of the IFNγ sequence from the koala will not only assist in understanding this species' response to its most important pathogen but will also provide further insight into the evolution of the marsupial immune system

Effect of induced airway inflammation in asthma : the expression of trefoil factors, secretoglobins and genes involved in histone acetylation

Asthma is an incapacitating disease of the respiratory system, which causes extensive morbidity and mortality worldwide. Asthma affects more than 300 million people globally(Masoli et al. 2004). In Australia, it affects 10.2% of the population (Masoli et al. 2004) and causes 60,000 people to be hospitalised annually. Health care expenditure due to asthma in Australia was $606 million in 2004–2005. There are four primary biological factors that function in the initiation and exacerbation of asthma. Airway inflammation is important as it is often the first response to an airway insult, initiating the three other components: bronchoconstriction, mucus hyper-secretion and hyper-reactivity. The mediators involved in asthma are still not well understood, and current anti-inflammatory corticosteroid treatments are not effective with all asthmatics. As there is currently no cure for asthma, and airway inflammation is the primary component of the disease, it is important that we understand and investigate the mediators of airway inflammation to look for a potential cure and to produce better therapeutics to treat the inflammation. Trefoil factors (TFFs) and secretoglobins (SCGBs) are small secreted proteins involved in the mediation of inflammation and epithelial restitution. TFFs are pro-inflammatory and SCGBs anti-inflammatory by nature. The hypothesis of this study is that in response to induced acute airway inflammation, the expression of TFF1 and TFF3 will increase and expression of SCGB1A1 and SCGB3A2 will decrease in non-asthmatics (N-A), asthmatics medicating with bronchodilators (A-BD) and asthmatics medicating with corticosteroids (A-ST). When comparing the three groups, we expect to see higher expression of the TFFs in the A-BD group compared to the N-A and A-ST groups, indicating that inflammation is mediated by TFFs in asthma and that corticosteroid medication controls their expression as part of the control of inflammation. We expect to see the opposite with SCGBs, with a greater decrease in the A-BD group compared to the other two groups, suggesting that the A-BD group has the least anti-inflammatory activity in response to inflammatory insult. Epigenetic modification plays a role in the regulation of genes that initiate disease states such as inflammatory conditions and cancers. Histone acetylation is one such modification, which involves the acetylation of histones in chromatin by histone acetyltransferases (HATs). This increases the transcription of genes involved with inflammation or enrols histone deacetylases (HDACs) to down-regulate the transcription of inflammatory genes. These HATs and HDACs work in a homeostatic fashion; however, in the event of inflammation, increased HAT activity can stimulate further inflammation, which is believed to be the mechanism involved in some inflammatory diseases. This study hypothesises that in response to inflammation, the expression of HDACs (HDAC1-5) will decrease and the expression of HATs (NCOA1-3, HAT-1 and CREBBP) will increase in all groups. When comparing the expression between the groups, it was expected that a greater decrease in HDACs and a greater increase in HATs will be seen in the A-BD group compared to the other two groups. This would identify histone acetylation as a mechanism involved in the inflammatory condition of asthma and indicate that corticosteroids may treat the inflammation in asthma at least in part by controlling histone acetylation. The aim of the project was to compare the expression of inflammatory genes TFF1, TFF3, SCGB1A1 and SCGB3A2, as well as to compare the gene expression of HDAC1-5, NCOA1-3, HAT-1 and CREBBP within and between N-A (n=15), A-BD (n=15) and A-ST (n=15) groups in response to inflammation. This was performed by collecting airway cells and proteins by sputum induction in three sessions. The sessions were coordinated into an initial baseline collection (SI-1), followed by a second session at least one week later (SI-2) and a third session, six hours after SI-2 to collect a sample containing the resultant acute inflammation caused in SI-2 (SI-3). Analysis of the SI-1 and SI-2 samples in all three groups had high amounts of variability between samples. The samples were taken at least one weak apart and the environmental stimuli on each participant outside of the testing sessions could not be controlled. For this reason, the SI-1 samples were not used for analysis; instead SI-2 and SI-3 samples were compared as they were same-day collections, reducing the probability of differences being due to anything other than the sputum induction. The gene expressions of the TFFs, SCGBs, HDACs and HATs were analysed using real-time PCR. Western blot analysis was performed to analyse the protein concentrations of the TFFs and SCGBs in secreted fractions of the sputum collection. Both the secreted and intracellular protein fractions collected from the sputum inductions for pre- and post-inflammation (SI-2, SI-3) samples of the N-A and A-BD groups were analysed using a proteomic method called iTRAQ. This allowed the comparison of the change in protein expression as a result of airway inflammation in each group. This technique was used as a discovery method to identify novel proteins that are modulated by induced acute airway inflammation. Any proteins of interest would then be further validated and used for future research. Inflammation was achieved in the SI-3 samples of the N-A group with a 21% unit increase in % neutrophils compared to SI-2 (p=0.01). The N-A group had a marked 5.5-fold decrease in HDAC1 gene expression in SI-3 compared to SI-2 (p=0.03). No differences were seen in any of the TFFs, SCGBs or any of the rest of the HDACs and HATs. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. However, non-significant analysis of the data displayed increases in TFF1 and TFF3, and decreases in SCGB1A1 and SCGB3A2 for the majority of SI-3 samples compared to SI-2. The A-BD group also presented a marked increase in neutrophils in the SI-3 samples compared to SI-2 (27% unit increase, p=0.04). The A-BD group had a significant increase in TFF3 and SCGB1A1 gene expression concomitant with induced acute airway inflammation. A 7.3-fold increase in TFF3 (p=0.05) in SI-3 indicated that TFF3 is linked to inflammation in asthmatics. A 2.8-fold increase in SCGB1A1 (p=0.03) indicated that this gene is also up-regulated, suggesting that this SCGB is expressed to try to combat induced acute airway inflammation. No significant changes were seen in any of the other genes analysed. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. However, non-significant analysis of the data displayed an increase in TFF1 and TFF3, and a decrease in SCGB1A1 and SCGB3A2 in SI-3, similar to that seen in the N-A group. The A-ST group was different from the A-BD group, characterised by the use of inhaled corticosteroid medication to treat asthma symptoms. Inhaled corticosteroids are known to treat asthma symptoms through the control of inflammation. Therefore, it was expected that corticosteroid medication would also control the expression of TFFs, SCGBs, HATs and HDACs. Gene expression results only identified a 7.6-fold decrease in HDAC2 expression in SI-3 (p=0.001), which is proposed to be due to the up-regulation of HDAC2 protein that is known to be a function of corticosteroid use. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. The gene expression in SI-2 and SI-3 in each group was compared. When comparing the A-BD group to the N-A group, a 9-fold increase in TFF3 (p=0.008) and a 34-fold increase in SCGB1A1 (p=0.03) were seen in the SI-3 samples. Comparisons of the A-ST group to the N-A group had an increased expression in SI-2 samples for HDAC5 (3.6-fold, p=0.04), NCOA2 (8.5-fold, p=0.04), NCOA3 (17-fold, p=0.01), HAT-1 (36-fold, p=0.003) and CREBBP (13-fold, p=0.001). The SI-3 samples in the A-ST group compared to the N-A group had increased expression for HDAC1 (6.4-fold, p=0.04), HDAC5 (5.2-fold, p=0.008), NCOA2 (9.6-fold, p=0.03), NCOA3 (16-fold, p=0.06), HAT-1 (41-fold, p<0.001) and CREBBP (31-fold, p=0.001). Comparisons of the A-ST group to the A-BD group had SI-2 increases in HDAC1 (3.8-fold, p=0.03), NCOA3 (4.5-fold, p=0.03), HAT-1 (5.3-fold, p=0.01) and CREBBP (23-fold, p=0.001), while SI-3 comparisons saw a decrease in HDAC2 (41-fold, p=0.008) and increases in HAT-1 (4.3-fold, p=0.003) and CREBBP (40-fold, p=0.001). Results showed that TFF3 and SCGB1A1 expression is higher in asthmatics than non-asthmatics and that histone acetylation is more active in the A-ST group than either the N-A or A-BD group, which suggests that histone acetylation activity may be positively correlated with asthma severity. The iTRAQ proteomic analysis of the secreted protein samples identified the SCGB1A1 protein and found it to be decreased in both the N-A and A-BD groups post-inflammation, but significantly so only in the A-BD group. Although no significant results were obtained from the western blot data, both groups displayed a decrease in SCGB1A1 concentration in SI-3 samples, suggesting a correlation with the proteomic data. Only 31 peptides were identified from the secreted samples. The intracellular iTRAQ analysis successfully identified 664 peptides, eight of which had differential expression in association with induced acute airway inflammation. Significant increases were seen in the A-BD group in SI-3 compared to SI-2 than in the N-A group in chloride intracellular channel protein 1, keratin-19, eosinophil cationic protein, calnexin, peroxiredoxin-5, and ATP-synthase delta subunit, while decreases were seen in cystatin-A and mucin-5AC. The iTRAQ analysis was only a discovery measure and further validation must be performed. In summary, the expression of TFFs and SCGBs differed between non-asthmatics and asthmatics. It is clear that TFF3 is active in the airway inflammation associated with asthma as indicated by an increase associated with inflammation in the A-BD group compared to the N-A group. Results for HDAC and HAT genes showed high HAT expression in the A-ST group compared to the N-A and A-BD groups, suggesting that histone acetyltransferases may be responsible for the characteristic unregulated inflammatory symptoms of asthmatics taking corticosteroids. Interestingly, corticosteroid medication did not seem to silence the expression of the analysed HAT genes, which indicates that corticosteroids may not control inflammation by direct regulation of HATs, but instead by competition, most probably with HDAC2 protein. As a discovery tool, iTRAQ is a potent method to both identify and compare the concentration of proteins between samples. The method is a powerful first step into the identification of novel proteins that are regulated in response to different treatments.