General practitioner and the control of sexually transmissible infections

Sexually transmissible infections (STIs), one of the major preventable health problems affecting the Australian population, are often asymptomatic and, if undetected, can cause sub-fertility, infertility and chronic morbidity. In addition to these significant and costly consequences, STIs increase the risk of transmission of HIV. Given that 80% of Australian patients attend their General Practitioner (GP) each year, GPs are well placed to have a significant impact on STI transmission by diagnosing and treating both asymptomatic and symptomatic disease. Good professional practice would suggest that all GPs will undertake certain actions when they are consulted by a patient who either has symptoms of an STI or who appears to be at risk of acquiring an STI. This expectation is based on the premise that all GPs share the same detailed knowledge of STI risk factors and symptoms. It assumes that they will have no difficulty in eliciting such information from the patient, that the patient will comply with STI testing and treatment and that the patient will return for follow-up, to ensure that they and their sexual partners have been adequately treated. Given the constraints of the real world in which general practice exists, the sensitive nature of sexual health, and the stigma associated with STIs, there are many barriers to achieving such an outcome. My own previous research has highlighted some of the difficulties experienced by GPs in the area of STI control. This study has used data from four different sources (policy and stakeholder documents, literature, key informant interviews and my own past research) to examine ideal practice and actual practice in the prevention and treatment of STIs. A number of discrepancies were identified, and from these arose a series of recommendations for ways of making STI control in general practice less complex. To ensure that the results of the study were firmly embedded in the reality of general practice, comments on the recommendations were sought from GPs employed in a variety of practice settings, including those with low STI caseloads. These comments were used to modify the recommendations to ensure they would offer a practical and effective contribution to STI control in Victoria.

Ecology and control of the southern saltmarsh mosquito, Ochlerotatus Camptorhynchus(Thomson), in Victoria

This study has revealed important ecological attributes of the southern saltmarsh mosquito in Victoria, resulting in an increased understanding of population peaks and their relation to Ross River virus disease and meteorological factors. Together with new information on its larval development, these results have further increased options for its control by local governments and public health authorities.

Effects of a fox removal program on small and medium-sized mammal population dynamics within the Anglesea Heathlands, Victoria

This thesis assessed the diet of foxes within the ALCOA lease area of Anglesea to determine which native and introduced species foxes were eating. Results showed that Swamp Wallaby was regularly eaten but many other mammals, birds, insects and reptiles were also consumed. The response of native mammals to seasonal fox removal was also determined.

Conservation genetics of the New Holland mouse Pseudomys novaehollandiae, Waterhouse, 1843 (Rodentia: Muridae) : an analysis of mitochondrial DNA control region variation

An investigation of the genetic diversity of New Holland mouse populations using DNA. Ten distinct restriction enzyme fragment patterns or haplotypes were detected. From the fragment patterns, estimates of genetic divergence between the haplotypes revealed a degree of genetic structuring within New Holland mouse with four population assemblages apparent.

RCT of a client-centred, caseworker-delivered smoking cessation intervention for a socially disadvantaged population

Background: Disadvantaged groups are an important target for smoking cessation intervention. Smoking rates are markedly higher among severely socially disadvantaged groups such as indigenous people, the homeless, people with a mental illness or drug and alcohol addiction, and the unemployed than in the general population. This proposal aims to evaluate the efficacy of a client-centred, caseworker delivered cessation support intervention at increasing validated self reported smoking cessation rates in a socially disadvantaged population.
Methods/Design: A block randomised controlled trial will be conducted. The setting will be a non-government organisation, Community Care Centre located in New South Wales, Australia which provides emergency relief and counselling services to predominantly government income assistance recipients. Eligible clients identified as smokers during a baseline touch screen computer survey will be recruited and randomised by a trained research assistant located in the waiting area. Allocation to intervention or control groups will be determined by time periods with clients randomised in one-week blocks. Intervention group clients will receive an intensive client centred smoking cessation intervention offered by the caseworker over two face-to-face and two telephone contacts. There will be two primary outcome measures obtained at one, six, and 12 month follow-up: 1) 24-hour expired air CO validated self-reported smoking cessation and 2) 7-day self-reported smoking cessation. Continuous abstinence will also be measured at six and 12 months follow up.
Discussion: This study will generate new knowledge in an area where the current information regarding the most effective smoking cessation approaches with disadvantaged groups is limited.

The Cool Little Kids randomised controlled trial population-level early prevention for anxiety disorders

Background: The World Health Organization predicts that by 2030 internalising problems (e.g. depression and anxiety) will be second only to HIV/AIDS in international burden of disease. Internalising problems affect 1 in 7 school aged children, impacting on peer relations, school engagement, and later mental health, relationships and employment. The development of early childhood prevention for internalising problems is in its infancy. The current study follows two successful ‘efficacy’ trials of a parenting group intervention to reduce internalising disorders in temperamentally inhibited preschool children. Cool Little Kids is a population-level randomised trial to determine the impacts of systematically screening preschoolers for inhibition then offering a parenting group intervention, on child internalising problems and economic costs at school entry.
Methods/Design: This randomised trial will be conducted within the preschool service system, attended by more than 95% of Australian children in the year before starting school. In early 2011, preschool services in four local government areas in Melbourne, Australia, will distribute the screening tool. The ≈16% (n≈500) with temperamental inhibition will enter the trial. Intervention parents will be offered Cool Little Kids, a 6-session group program in the local community, focusing on ways to develop their child’s bravery skills by reducing overprotective parenting interactions. Outcomes one and two years post-baseline will comprise child internalising diagnoses and symptoms, parenting interactions, and parent wellbeing. An economic evaluation (costconsequences framework) will compare incremental differences in costs of the intervention versus control children to incremental differences in outcomes, from a societal perspective. Analyses will use the intention-to-treat principle, using logistic and linear regression models (binary and continuous outcomes respectively) to compare outcomes between the trial arms.
Discussion: This trial addresses gaps for internalising problems identified in the 2004 World Health Organization Prevention of Mental Disorders report. If effective and cost-effective, the intervention could readily be applied at a population level. Governments consider mental health to be a priority, enhancing the likelihood that an effective early prevention program would be adopted in Australia and internationally.

Tobacco smoking as a risk factor for major depressive disorder : a population-based study

Background : Smoking is disproportionately prevalent among people with psychiatric illness.

Aims : To investigate smoking as a risk factor for major depressive disorder.

Method : A population-based sample of women was studied using case–control and retrospective cohort study designs. Exposure to smoking was self-reported, and major depressive disorder diagnosed using the Structured Clinical Interview for DSM–IV–TR (SCID–I/NP).

Results : Among 165 people with major depressive disorder and 806 controls, smoking was associated with increased odds for major depressive disorder (age-adjusted odds ratio (OR)=1.46, 95% CI 1.03–2.07). Compared with non-smokers, odds for major depressive disorder more than doubled for heavy smokers (>20 cigarettes/day). Among 671 women with no history of major depressive disorder at baseline, 13 of 87 smokers and 38 of 584 non-smokers developed de novo major depressive disorder during a decade of follow-up. Smoking increased major depressive disorder risk by 93% (hazard ratio (HR)=1.93, 95% CI 1.02–3.69); this was not explained by physical activity or alcohol consumption.

Conclusions : Evidence from cross-sectional and longitudinal data suggests that smoking increases the risk of major depressive disorder in women.

A multiple population genetic algorithm and its application in fuzzy controller

Genetic Algorithm is an important optimization technique, though its application in Fuzzy system is usually limited by problems like local optimal and premature convergence. With an aim to improve the performance of simple Genetic Algorithm, we propose a multi-population genetic algorithm MP-GA which uses two populations collaborating with each other, and apply it to fuzzy controller design to optimize its control rules. The simulation results of Inverted Pendulum demonstrate the effectiveness of this proposed method.

Population genetics of the spotted seahorse (Hippocampus kuda) in Thai waters : implications for conservation

A population genetics approach was used to investigate the genetic diversity of the spotted seahorse (Hippocampus kuda) in Thai waters; specifically, the degree of genetic differentiation and species evolution was inferred from sequence analysis of 353 bp of the mitochondrial (mt)DNA control region. The data were then used to identify discrete populations in Thai waters for effective conservation and management. Spotted seahorses were collected from 4 regions on the east and west coasts of the Gulf of Thailand and a geographically separated region in the Andaman Sea. Of the 101 mtDNA sequences analyzed, 7 haplotypes were identified, 5 of which were shared among individuals from the east and west coasts of the Gulf of Thailand. The remaining haplotypes were restricted to individuals from the Andaman Sea. Nucleotide and haplotype diversities were similar within the Gulf of Thailand samples, whereas diversity was lower in the Andaman Sea sample. Genetic differentiation appeared between pairs of samples from the Gulf of Thailand and Andaman Sea (FST, p < 0.0001). A large genetic variance appeared among the 2 population groups (94.46%, ΦCT = 0.94464, p < 0.01). A Neighbor-joining tree indicated that individuals from the Gulf of Thailand and Andaman Sea formed 2 phylogenetically distinct groups, which were segregated into different population-based clades. While results reported here indicate that populations from the Gulf of Thailand and Andaman Sea should be treated as separate conservation units, a larger sample size from the Andaman Sea is required to confirm this genetic partitioning and low level of diversity observed in the present study.

Outcomes of population based language promotion for slow to talk toddlers at ages 2 and 3 years: let’s learn language cluster randomised controlled trial

Objective To determine the benefits of a low intensity parent-toddler language promotion programme delivered to toddlers identified as slow to talk on screening in universal services.
Design Cluster randomised trial nested in a population based survey.
Setting Three local government areas in Melbourne, Australia.
Participants Parents attending 12 month well child checks over a six month period completed a baseline questionnaire. At 18 months, children at or below the 20th centile on an expressive vocabulary checklist entered the trial.
Intervention Maternal and child health centres (clusters) were randomly allocated to intervention (modified “You Make the Difference” programme over six weekly sessions) or control (“usual care”) arms.
Main outcome measures The primary outcome was expressive language (Preschool Language Scale-4) at 2 and 3 years; secondary outcomes were receptive language at 2 and 3 years, vocabulary checklist raw score at 2 and 3 years, Expressive Vocabulary Test at 3 years, and Child Behavior Checklist/1.5-5 raw score at 2 and 3 years.
Results 1217 parents completed the baseline survey; 1138 (93.5%) completed the 18 month checklist, when 301 (26.4%) children had vocabulary scores at or below the 20th centile and were randomised (158 intervention, 143 control). 115 (73%) intervention parents attended at least one session (mean 4.5 sessions), and most reported high satisfaction with the programme. Interim outcomes at age 2 years were similar in the two groups. Similarly, at age 3 years, adjusted mean differences (intervention−control) were −2.4 (95% confidence interval −6.2 to 1.4; P=0.21) for expressive language; −0.3 (−4.2 to 3.7; P=0.90) for receptive language; 4.1 (−2.3 to 10.6; P=0.21) for vocabulary checklist; −0.5 (−4.4 to 3.4; P=0.80) for Expressive Vocabulary Test; −0.1 (−1.6 to 1.4; P=0.86) for externalising behaviour problems; and −0.1 (−1.3 to 1.2; P=0. 92) for internalising behaviour problems.
Conclusion This community based programme targeting slow to talk toddlers was feasible and acceptable, but little evidence was found that it improved language or behaviour either immediately or at age 3 years.

More than mere numbers: the impact of lethal control on the social stability of a top-order predator

Population control of socially complex species may have profound ecological implications that remain largely invisible if only their abundance is considered. Here we discuss the effects of control on a socially complex top-order predator, the dingo (Canis lupus dingo). Since European occupation of Australia, dingoes have been controlled over much of the continent. Our aim was to investigate the effects of control on their abundance and social stability. We hypothesized that dingo abundance and social stability are not linearly related, and proposed a theoretical model in which dingo populations may fluctuate between three main states: (A) below carrying capacity and socially fractured, (B) above carrying capacity and socially fractured, or (C) at carrying capacity and socially stable. We predicted that lethal control would drive dingoes into the unstable states A or B, and that relaxation of control would allow recovery towards C. We tested our predictions by surveying relative abundance (track density) and indicators of social stability (scent-marking and howling) at seven sites in the arid zone subject to differing degrees of control. We also monitored changes in dingo abundance and social stability following relaxation and intensification of control. Sites where dingoes had been controlled within the previous two years were characterized by low scent-marking activity, but abundance was similar at sites with and without control. Signs of social stability steadily increased the longer an area was allowed to recover from control, but change in abundance did not follow a consistent path. Comparison of abundance and stability among all sites and years demonstrated that control severely fractures social groups, but that the effect of control on abundance was neither consistent nor predictable. Management decisions involving large social predators must therefore consider social stability to ensure their conservation and ecological functioning.

Fruit and vegetable consumption and the risk of proximal colon, distal colon and rectal cancers in a case-control study in Western Australia

Background Fruits and vegetables (F/V) have been examined extensively in nutrition research in relation to colorectal cancer (CRC). However, their protective effect is subject to debate, possibly because of different effects on different subsites of the large bowel.

Objective To determine whether any association between F/V consumption and risk of CRC differed by subsite of the bowel (proximal colon, distal colon, and rectum).

Design The Western Australian Bowel Health Study is a population-based, case-control study conducted between June 2005 and August 2007. Complete food frequency questionnaire data were analysed from 834 CRC cases and 939 controls. Logistic regression analysis was used to estimate the effects of quartiles of F/V intake on risk of CRC at different subsites. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for CRC overall and for the three separate subsites.

Results Risk of proximal colon cancer and rectal cancer was not associated with intakes of total F/V, total vegetable, or total fruit. Brassica vegetable intake was inversely related with proximal colon cancer (Q4 vs Q1 OR 0.62; 95% CI 0.41 to 0.93). For distal colon cancer, significant negative trends were seen for total F/V, and total vegetable intake. Distal colon cancer risk was significantly decreased for intake of dark yellow vegetables (Q4 vs Q1 OR 0.61; 95% CI 0.41 to 0.92) and apples (Q4 vs Q1 OR 0.51; 95% CI 0.34 to 0.77). An increased risk for CRC was found to be associated with intake of fruit juice (Q4 vs Q1 OR 1.74; 95% CI 1.24 to 2.45).

Conclusions Our results suggest that different F/V may confer different risks for cancer of the proximal colon, distal colon, or rectum. Future studies might consider taking into account the location of the tumor when examining the relation between F/V consumption and risk of CRC.

Association between dependent smoking and a polymorphism in the tyrosine hydroxylase gene in a prospective population-based study of adolescent health

This study reports pilot data on an association between tobacco dependence and a five-allele tetranucleotide repeat polymorphism in the first intron of the tyrosine hydroxylase (TH) gene. One hundred and twenty-six Australian adolescents who had participated in the Health in Transition Study (1993–1997), and who showed patterns of either dependent or nondependent smoking across four waves of data collection, consented to participation in the pilot study. The smoking status of those recruited was confirmed using a telephone-administered drug use questionnaire during 2000. Tobacco dependence was defined as smoking more than 6 days per week and more than 10 cigarettes per day during wave 5 (year 2000) and at lfeast one prior wave (n = 58). A second, more stringent phenotype included smoking within an hour of waking (n = 37). The control group comprised adolescents who had used tobacco but had remained low-level social smokers across each wave of data (n = 56). DNA was collected using a mouthwash procedure. Using the more strictly defined tobacco dependence phenotype, and after adjusting for sex, a significant protective association was found between the K4 allele and tobacco dependence (OR 0.27, 95% confidence interval [CI] 0.09, 0.82). No association was found using the liberal criteria of tobacco dependence (OR 0.51, 95% confidence interval [CI] 0.23, 1.2). These preliminary results replicate a previous association between tobacco use and the K4 allele of the TH gene (Lerman et al., 1997). The potential significance of including time to first cigarette in definitions of tobacco dependence and the possible role that these TH variants might play in tobacco dependence are discussed.

The Bassian Isthmus and the major ocean currents of southeast Australia influence the phylogeography and population structure of a southern Australian intertidal barnacle Catomerus polymerus (Darwin)

Southern Australia is currently divided into three marine biogeographical provinces based on faunal distributions and physical parameters. These regions indicate eastern and western distributions, with an overlap occurring in the Bass Strait in Victoria. However, studies indicate that the boundaries of these provinces vary depending on the species being examined, and in particular on the mode of development employed by that species, be they direct developers or planktonic larvae dispersers. Mitochondrial DNA sequence analysis of the surf barnacle Catomerus polymerus in southern Australia revealed an east–west phylogeographical split involving two highly divergent clades (cytochrome oxidase I 3.5 ± 0.76%, control region 6.7 ± 0.65%), with almost no geographical overlap. Spatial genetic structure was not detected within either clade, indicative of a relatively long-lived planktonic larval phase. Five microsatellite loci indicated that C. polymerus populations exhibit relatively high levels of genetic divergence, and fall into four subregions: eastern Australia, central Victoria, western Victoria and Tasmania, and South Australia. F_ST values between eastern Australia (from the eastern mitochondrial DNA clade) and the remaining three subregions ranged from 0.038 to 0.159, with other analyses indicating isolation by distance between the subregions of western mitochondrial origin. We suggest that the east–west division is indicative of allopatric divergence resulting from the emergence of the Bassian land-bridge during glacial maxima, preventing gene flow between these two lineages. Subsequently, contemporary ecological conditions, namely the East Australian, Leeuwin, and Zeehan currents and the geographical disjunctions at the Coorong and Ninety Mile Beach are most likely responsible for the four subregions indicated by the microsatellite data.