A Comparison of Modified Food Chaining and Simultaneous Presentation Plus Nonremoval of the Spoon to Treat Food Selectivity in Children with Autism Spectrum Disorder

Feeding disorders can range from mild (e.g., food selectivity by taste or texture) to severe (e.g., total food refusal; Bachmeyer, 2009). If left untreated, feeding disorders can result in serious health ramifications, including malnutrition, growth delays, and developmental delays (Kern & Marder, 1996). Recent studies comparing commonly used occupational therapy (OT) treatments and empirically supported applied behavior analysis (ABA) treatments found that the ABA treatments were effective for all children while the OT treatments were ineffective for all children exposed to the OT treatment (Addison et al., 2012; Peterson, Piazza, & Volkert, 2016). We used a multielement design to compare a modified version of a commonly used treatment, food chaining, and an empirically validated ABA treatment to treat the food selectivity of 2 children with autism spectrum disorder (ASD). For both children, consumption of the target foods only increased during the ABA-treatment condition. We subsequently faded the size of the preferred food within the simultaneous-presentation arrangement, moved to a sequential-presentation arrangement, and then thinned the schedule of reinforcement. We will discuss the results within the context of treatment implications, limitations, and suggestions for future research

The delivery of DNA vaccines using particulate and non-particulate adjuvants.

The use of DNA for vaccination has many potential advantages over conventional vaccines. However, one of the drawbacks associated with this type of vaccination is the apparent lack of immunogenicity of plasmid DNA itself. Traditional aluminium-based adjuvants (alum) have been used to augment the immune response to DNA vaccines, however they have been implicated in allergic responses and the emerging condition macrophagic myofasciitis. The use of zinc oxide as an alternative to alum was investigated for protein antigens and plasmid DNA. An adjuvant effect was observed when zinc oxide was used in combination with other known adjuvants (polymeric microparticles or chitosan) to deliver protein antigen. Prime / boost strategies; priming with plasmid DNA and boosting with protein antigen have been shown to augment cellular and humoral immune responses to many antigens. The coadministration of plasmid DNA and protein antigen as either the priming or booster dose elicited a mixed humoral / cellular response, which was superior to the responses generated by the use of either component alone. Microparticles have been shown to augment the immune response to DNA vaccines, however the plasmid DNA can be degraded within the microparticles as a result of the acidic microclimate generated during polymer degradation. In this study, the co-encapsulation of magnesium hydroxide was observed to increase the stability of plasmid DNA inside the microparticles during polymer degradation. Microencapsulated MUC1 plasmid DNA was investigated for use as a cancer vaccine. Naked DNA has previously been shown to suppress tumour growth when administered intramuscularly. In this study, microencapsulated plasmid DNA delivered subcutaneously led to the greatest suppression of tumour growth. These studies show the initial feasibility of the approaches discussed to deliver plasmid DNA for vaccination and to act as potential adjuvants as an alternative to alum for DNA vaccines

Suicidal behaviour in young people accessing mental health care

Rates of suicidal behaviour in young people have increased despite increased awareness and investment in suicide prevention. Mental health system reform has led to the development of early intervention mental health services and new clinical cohorts distinct from adults accessing mental health services. The effectiveness of clinical suicide prevention relies on in-depth, contemporaneous understanding of suicidal behaviour in clinical populations. The overall aim of this thesis was to generate new scientific understanding of suicidal behaviour in these new clinical cohorts, which may be applied in clinical services to increase the impact of clinical suicide prevention. Chapter 2 uses systematic review and meta-analyses to assess the predictive performance of key risk factors used to direct clinical suicide prevention. Chapter 3 then considers the application of machine learning to the prediction of suicidal behaviour. Chapter 4 explores the utility of cognition as a potential biomarker of suicidal behaviour in young people. Finally, Chapter 5 uses data-linkage to characterise premature mortality and identify health service use predictors of suicide and accident-related deaths in young people accessing early intervention youth mental health services. In summary, there are unique social, clinical and cognitive predictors of suicidal behaviour in young people accessing clinical services. The high burden of disease associated with these behaviours suggests that all young people accessing mental health services should receive evidence-based suicide prevention interventions. Further, the high rates of adverse outcomes due to accident and injury, drug and alcohol use and emergency department presentations, suggest that developing strategies and designing interventions to address a broader construct of harm should be considered

Enhanced heterogeneity of rpoB in Mycobacterium tuberculosis found at low pH.

OBJECTIVES: The aim of this study was to gain an insight into the molecular mechanisms of the evolution of rifampicin resistance in response to controlled changes in the environment. METHODS: We determined the proportion of rpoB mutants in the chemostat culture and characterized the sequence of mutations found in the rifampicin resistance-determining region of rpoB in a steady-state chemostat at pH 7.0 and 6.2. RESULTS: The overall proportion of rpoB mutants of strain H37Rv remained constant for 37 days at pH 7.0, ranging between 3.6 x 10(-8) and 8.9 x 10(-8); however, the spectrum of mutations varied. The most commonly detected mutation, serine to leucine mutation at codon 531 (S531L), increased from 40% to 89%, while other mutations (S531W, H526Y, H526D, H526R, S522L and D516V) decreased over the 37 day sampling period. Changing the pH from 7.0 to 6.2 did not significantly alter the overall proportion of mutants, but resulted in a decrease in the percentage of strains harbouring S531L (from 89% to 50%) accompanied by an increase in the range of different mutations from 4 to 12. CONCLUSIONS: The data confirm that the fitness of strains with the S531L mutation is greater than that of strains containing other mutations. We also conclude that at low pH the environment is permissive for a wider spectrum of mutations, which may provide opportunities for a successful mutant to survive

Using mobile technology to reduce engagement in stereotypy : a validation of decision-making algorithms

We developed an iOS app, the iSTIM, designed to support parents of children with autism spectrum disorders (ASD) in reducing common repetitive vocal and motor behavior (i.e., stereotypy). The purpose of our study was to preliminarily test the decision-making algorithms of the iSTIM using trained university students to implement the assessments and interventions. Specifically, we examined the effects of the iSTIM on stereotypy and functional engagement in 11 children with ASD within alternating treatment designs. Using the iSTIM reduced engagement in stereotypy for 8 participants and increased functional engagement in for 4 of those participants. Our results indicate that the iSTIM may decrease engagement in stereotypy, but that some of the decision-making algorithms may benefit from modifications prior to testing with parents