Induction of partial immunity in both males and females is sufficient to protect females against sexual transmission of Chlamydia

Sexually transmitted Chlamydia trachomatis causes infertility, and because almost 90% of infections are asymptomatic, a vaccine is required for its eradication. Mathematical modeling studies have indicated that a vaccine eliciting partial protection (non-sterilizing) may prevent Chlamydia infection transmission, if administered to both sexes before an infection. However, reducing chlamydial inoculum transmitted by males and increasing infection resistance in females through vaccination to elicit sterilizing immunity has yet to be investigated experimentally. Here we show that a partially protective vaccine (chlamydial major outer membrane protein (MOMP) and ISCOMATRIX (IMX) provided sterilizing immunity against sexual transmission between immunized mice. Immunizing male or female mice before an infection reduced chlamydial burden and disease development, but did not prevent infection. However, infection and inflammatory disease responsible for infertility were absent in 100% of immunized female mice challenged intravaginally with ejaculate collected from infected immunized males. In contrast to the sterilizing immunity generated following recovery from a previous chlamydial infection, protective immunity conferred by MOMP/IMX occurred independent of resident memory T cells. Our results demonstrate that vaccination of males or females can further protect the opposing sex, whereas vaccination of both sexes can synergize to elicit sterilizing immunity against Chlamydia sexual transmission.

Human and pathogen factors associated with chlamydia trachomatis-related infertility in women

Chlamydia trachomatis is the most common bacterial sexually transmitted pathogen worldwide. Infection can result in serious reproductive pathologies, including pelvic inflammatory disease, ectopic pregnancy, and infertility, in women. However, the processes that result in these reproductive pathologies have not been well defined. Here we review the evidence for the human disease burden of these chlamydial reproductive pathologies. We then review human-based evidence that links Chlamydia with reproductive pathologies in women. We present data supporting the idea that host, immunological, epidemiological, and pathogen factors may all contribute to the development of infertility. Specifically, we review the existing evidence that host and pathogen genotypes, host hormone status, age of sexual debut, sexual behavior, coinfections, and repeat infections are all likely to be contributory factors in development of infertility. Pathogen factors such as infectious burden, treatment failure, and tissue tropisms or ascension capacity are also potential contributory factors. We present four possible processes of pathology development and how these processes are supported by the published data. We highlight the limitations of the evidence and propose future studies that could improve our understanding of how chlamydial infertility in women occurs and possible future interventions to reduce this disease burden.

Using internet search queries for infectious disease surveillance: screening diseases for suitability

Background Internet-based surveillance systems provide a novel approach to monitoring infectious diseases. Surveillance systems built on internet data are economically, logistically and epidemiologically appealing and have shown significant promise. The potential for these systems has increased with increased internet availability and shifts in health-related information seeking behaviour. This approach to monitoring infectious diseases has, however, only been applied to single or small groups of select diseases. This study aims to systematically investigate the potential for developing surveillance and early warning systems using internet search data, for a wide range of infectious diseases. Methods Official notifications for 64 infectious diseases in Australia were downloaded and correlated with frequencies for 164 internet search terms for the period 2009–13 using Spearman’s rank correlations. Time series cross correlations were performed to assess the potential for search terms to be used in construction of early warning systems. Results Notifications for 17 infectious diseases (26.6%) were found to be significantly correlated with a selected search term. The use of internet metrics as a means of surveillance has not previously been described for 12 (70.6%) of these diseases. The majority of diseases identified were vaccine-preventable, vector-borne or sexually transmissible; cross correlations, however, indicated that vector-borne and vaccine preventable diseases are best suited for development of early warning systems. Conclusions The findings of this study suggest that internet-based surveillance systems have broader applicability to monitoring infectious diseases than has previously been recognised. Furthermore, internet-based surveillance systems have a potential role in forecasting emerging infectious disease events, especially for vaccine-preventable and vector-borne diseases

Teenagers' perceptions of advertising in the online social networking environment : an exploratory study

This study explores teenager perceptions towards advertising in the online social networking environment. The future of online social networking sites is dependant upon the continued support of advertisers in this new medium, which is linked to the acceptance of advertising on these sites by their targeted audience. This exploratory study used the qualitative research methods of focus groups and in-depth personal interviews to gain insights from the teenager participants. The literature review in Chapter Two examined the previous research into advertising theories, consumer attitudes and issues such as advertising avoidance, advertising as a service and trust and privacy in the online social networking environment. The teenage consumer was also examined as were the influences of social identity theory. From this literature review eleven propositions were formed which provided a structure to the analysis of the research. Chapter Three outlined the multi-method research approach of using focus groups and in-depth interviews. The key findings were outlined in Chapter Four and Chapter Five provides discussion regarding these findings and the implications for theory and advertising practice. The main findings from this study suggest that teenagers have very high levels of advertising avoidance and are sceptical towards advertising on their online social networking sites. They have an inherent distrust of commercial messages in the online social networking environment; however they are extremely trusting with the information that they disclose online. They believe that if their site is classified as private, then the information disclosed on this site is not accessible to anyone. The study explores the reasons behind these views. This research has resulted in the identification of seven motivations behind online social networking use. A new model of advertising avoidance in the online social networking environment is also presented and discussed. This model makes a contribution towards filling the gap in available research on online social networking sites and advertising perception. The findings of this study have also resulted in the identification of the characteristics of online social networking sites as an advertising medium. The newness of online social networking sites coupled with the enthusiastic adoption of online social networking by the teenage demographic means that this exploratory study will be of interest to both academics and practitioners alike.

When and how to treat pulmonary non-tuberculous mycobacterial diseases

Nontuberculous mycobacteria are ubiquitous environmental organisms that have been recognised as a cause of pulmonary infection for over 50 years. Traditionally patients have had underlying risk factors for development of disease; however the proportion of apparently immunocompetent patients involved appears to be rising. Not all patients culture-positive for mycobacteria will have progressive disease, making the diagnosis difficult, though criteria to aid in this process are available. The two main forms of disease are cavitary disease (usually involving the upper lobes) and fibronodular bronchiectasis (predominantly middle and lingular lobes). For patients with disease, combination antibiotic therapy for 12-24 months is generally required for successful treatment, and this may be accompanied by drug intolerances and side effects. Published success rates range from 30-82%. As the progression of disease is variable, for some patients, attention to pulmonary hygiene and underlying diseases without immediate antimycobacterial therapy may be more appropriate. Surgery can be a useful adjunct, though is associated with risks. Randomised controlled trials in well described patients would provide stronger evidence-based data to guide therapy of NTM lung diseases, and thus are much needed.

Natural enemies of Paropsis atomaria Olivier (Coleoptera: Chrysomelidae) in south-eastern Queensland eucalypt plantations

Abstract A field survey for natural enemies of Paropsis atomaria was conducted at two south-eastern Queensland Eucalyptus cloeziana plantation sites during 2004–2005. Primary egg and larval parasitoids and associated hyperparasitoids were identified to genus or species, and parasitism rates were determined throughout the season. Predators were identified to family level but their impact was not quantified. P. atomaria adults were also examined as potential hosts for parasitic mites and nematodes. An undescribed species of Neopolycystus (Pteromalidae) was the major primary egg parasitoid species reared from egg batches, parasitising half of all egg batches collected. Three hyperparasitoid species (Baeoanusia albifunicle (Encyrtidae), Neblatticida sp. (Encyrtidae) and Aphaneromella sp. (Platygasteridae) were present, representing around one-quarter to one-third of all emergent wasps; this is the first host association record for Neopolycystus–B. albifunicle. In contrast to populations of P. atomaria from the Australian Capital Territory, primary larval parasitism was very low, around 1%, and attributable only to the tachinid flies Anagonia sp. and Paropsivora sp. However, the presence of the sit-and-wait larval hyperparasitoid, Perilampus sp. (Perilampidae) was high, emerging from around 17% of tachinid pupae, with planidia infesting a further 40% of unparasitised hosts. Three species of podapolipid mites parasitised sexually mature P. atomaria adults, while no nematodes were found in this study. Spiders were the most common predators and their abundance was positively correlated with P. atomaria adult and egg numbers. Although natural enemy species composition was identical between our two study sites, significant differences in abundance and frequency were found between sites

The Biology, Epidemiology, and Management of Rice Tungro Disease in Asia

Many farmers in South and Southeast Asia describe rice tungro disease as a cancer disease because of the severe damage it causes and the difficulty of controlling it (121). As the most important of the 14 rice viral diseases, tungro was first recognized as a leafhopper-transmitted virus disease in 1963 (88). However, tungro, which means “degenerated growth” in a Filipino dialect, has a much longer history. It is almost certain that tungro was responsible for a disease outbreak that occurred in 1859 in Indonesia, which was referred to at the time as mentek (83). In the past, a variety of names has been given to tungro, including accep na pula in the Philippines, penyakit merah in Malaysia, and yelloworange leaf in Thailand (83).

Aggression in Sexually Abused Trafficked Girls and Efficacy of Intervention

The broad objective of this study was to understand the incidence and severity of aggression among sexually abused girls who were trafficked and who were then further used for commercial sexual exploitation (referred to subsequently as sexually abused trafficked girls). In addition, the impact of counseling for minimizing aggression in these girls was investigated. A group of 120 sexually abused trafficked Indian girls and a group of 120 nonsexually abused Indian girls, aged 13 to 18, participated in the study. The sexually abused trafficked girls were purposively selected from four shelters located in and around Kolkata, India. The nonsexually abused girls were selected randomly from four schools situated near the shelters, and these girls were matched by age with the sexually abused trafficked girls. Data were collected using a Background Information Schedule and a standardized psychological test, that is, The Aggression Scale. Results revealed that 16.7% of the girls were first sexually abused between 6 and 9 years of age, 37.5% between 10 and 13 years of age, and 45.8% between 14 and 17 years of age. Findings further revealed that 4.2% of the sexually abused trafficked girls demonstrated saturated aggression, and 26.7% were highly aggressive, that is, extremely frustrated and rebellious. Across age groups, the sexually abused trafficked girls suffered from more aggression (p < .05), compared with the nonvictimized girls. Psychological interventions, such as individual and group counseling, were found to have a positive impact on the sexually abused trafficked girls. These findings should motivate counselors to deal with sexually abused children. It is also hoped that authorities in welfare homes will understand the importance of counseling for sexually abused trafficked children, and will appoint more counselors for this purpose.

Evaluating Two Mass Screening Methods for Tungro Disease Resistance

Tungro is one of the most destructive viral diseases of rice in South and Southeast Asia. It is associated with two viruses---rice tungro bacilliform virus (RTBV) ,and rice tungro spherical virus (RTSV) (Hibino et al 1978). Both viruses are transmitted by the green leafhopper (GLH) Nephotettix virescens (Ling 1979), However, prior acquisition of RTSV is required for Ihe transmission of RTBV alone (Hibino 1983). Plants infected with both viruses show severe stunting and yellowing. Those infected with RTBV alone show mild stunting but no leaf discoloration whereas those infected with RTSV alone do not show any apparent symptoms (Hibino el al 1978). Since the late 1960s, tungro has been mainly managed through varietal resistance (Khush 1989). The instability of resistant varieties in the field (Dahal et .a1 1990) led to a reexamination of the nature of the incorporated sources of resistance and to the adoption of more precise and more accurate screening methods.

Bayesian methodology for genetics of complex diseases

Genetic research of complex diseases is a challenging, but exciting, area of research. The early development of the research was limited, however, until the completion of the Human Genome and HapMap projects, along with the reduction in the cost of genotyping, which paves the way for understanding the genetic composition of complex diseases. In this thesis, we focus on the statistical methods for two aspects of genetic research: phenotype definition for diseases with complex etiology and methods for identifying potentially associated Single Nucleotide Polymorphisms (SNPs) and SNP-SNP interactions. With regard to phenotype definition for diseases with complex etiology, we firstly investigated the effects of different statistical phenotyping approaches on the subsequent analysis. In light of the findings, and the difficulties in validating the estimated phenotype, we proposed two different methods for reconciling phenotypes of different models using Bayesian model averaging as a coherent mechanism for accounting for model uncertainty. In the second part of the thesis, the focus is turned to the methods for identifying associated SNPs and SNP interactions. We review the use of Bayesian logistic regression with variable selection for SNP identification and extended the model for detecting the interaction effects for population based case-control studies. In this part of study, we also develop a machine learning algorithm to cope with the large scale data analysis, namely modified Logic Regression with Genetic Program (MLR-GEP), which is then compared with the Bayesian model, Random Forests and other variants of logic regression.

Exploring health behaviour determinants of ageing Australians with chronic diseases

Background: Chronic disease presents overwhelming challenges to elderly patients, their families, health care providers and the health care system. The aim of this study was to explore a theoretical model for effective management of chronic diseases, especially type 2 diabetes mellitus and/or cardiovascular disease. The assumed theoretical model considered the connections between physical function, mental health, social support and health behaviours. The study effort was to improve the quality of life for people with chronic diseases, especially type 2 diabetes and/or cardiovascular disease and to reduce health costs. Methods: A cross-sectional post questionnaire survey was conducted in early 2009 from a randomised sample of Australians aged 50 to 80 years. A total of 732 subjects were eligible for analysis. Firstly, factors influencing respondents‘ quality of life were investigated through bivariate and multivariate regression analysis. Secondly, the Theory of Planned Behaviour (TPB) model for regular physical activity, healthy eating and medication adherence behaviours was tested for all relevant respondents using regression analysis. Thirdly, TPB variable differences between respondents who have diabetes and/or cardiovascular disease and those without these diseases were compared. Finally, the TPB model for three behaviours including regular physical activity, healthy eating and medication adherence were tested in respondents with diabetes and/or cardiovascular diseases using Structure Equation Modelling (SEM). Results: This was the first study combining the three behaviours using a TPB model, while testing the influence of extra variables on the TPB model in one study. The results of this study provided evidence that the ageing process was a cumulative effect of biological change, socio-economic environment and lifelong behaviours. Health behaviours, especially physical activity and healthy eating were important modifiable factors influencing respondents‘ quality of life. Since over 80% of the respondents had at least one chronic disease, it was important to consider supporting older people‘s chronic disease self-management skills such as healthy diet, regular physical activity and medication adherence to improve their quality of life. Direct measurement of the TPB model was helpful in understanding respondents‘ intention and behaviour toward physical activity, healthy eating and medication adherence. In respondents with diabetes and/or cardiovascular disease, the TPB model predicted different proportions of intention toward three different health behaviours with 39% intending to engage in physical activity, 49% intending to engage in healthy eating and 47% intending to comply with medication adherence. Perceived behavioural control, which was proven to be the same as self-efficacy in measurement in this study, played an important role in predicting intention towards the three health behaviours. Also social norms played a slightly more important role than attitude for physical activity and medication adherence, while attitude and social norms had similar effects on healthy eating in respondents with diabetes and/or cardiovascular disease. Both perceived behavioural control and intention directly predicted recent actual behaviours. Physical activity was more a volitional control behaviour than healthy eating and medication adherence. Step by step goal setting and motivation was more important for physical activity, while accessibility, resources and other social environmental factors were necessary for improving healthy eating and medication adherence. The extra variables of age, waist circumference, health related quality of life and depression indirectly influenced intention towards the three behaviours mainly mediated through attitude and perceived behavioural control. Depression was a serious health problem that reduced the three health behaviours‘ motivation, mediated through decreased self-efficacy and negative attitude. This research provided evidence that self-efficacy is similar to perceived behavioural control in the TPB model and intention is a proximal goal toward a particular behaviour. Combining four sources of information in the self-efficacy model with the TPB model would improve chronic disease patients‘ self management behaviour and reach an improved long-term treatment outcome. Conclusion: Health intervention programs that target chronic disease management should focus on patients‘ self-efficacy. A holistic approach which is patient-centred and involves a multidisciplinary collaboration strategy would be effective. Supporting the socio-economic environment and the mental/ emotional environment for older people needs to be considered within an integrated health care system.