Gender differences in emotionality and sociability in children with autism spectrum disorders

Background
Four times as many males are diagnosed with high functioning autism compared to females. A growing body of research that focused on females with autism spectrum disorder (ASD) questions the assumption of gender invariance in ASD. Clinical observations suggest that females with ASD superficially demonstrate better social and emotional skills than males with ASD, which may camouflage other diagnostic features. This may explain the under-diagnosis of females with ASD.

Methods
We hypothesised that females with ASD would display better social skills than males with ASD on a test of friendship and social function. One hundred and one 10- to 16-year-olds (ASD females, n = 25; typically developing (TD) females, n = 25; ASD males, n = 25; TD males, n = 26) were interviewed (using the friendship questionnaire (FQ)) with high scores indicating the child has close, empathetic and supportive relationships. One parent of each child completed the FQ to assess whether there are differences in perception of friendships between parents and children.

Results
It was found that, independent of diagnosis, females demonstrated higher scores on the FQ than males. Further, regardless of gender, children with ASD demonstrated lower scores than TD children. Moreover, the effect of ASD was independent of gender. Interestingly, females with ASD and TD males displayed similar scores on the FQ.

Conclusions
This finding is supported by clinical reports that females with ASD have more developed social skills than males with ASD. Further research is now required to examine the underlying causes for this phenomenon in order to develop gender-appropriate diagnostic criteria and interventions for ASD.

Community-onset Escherichia coli infection resistant to expanded- spectrum cephalosporins in low-prevalence countries

Background
By global standards the prevalence of community onset expanded-spectrum cephalosporin resistant Escherichia coli (ESC-R-EC) remains low in Australia and New Zealand. Of concern, our countries are in a unique position with high extramural resistance pressure from close population and trade links to Asia-Pacific neighbours with high ESC-R-EC rates. We aim to characterize the risks and dynamics of community onset ESC-R-EC in our low-prevalence region.

Methods
A case-control methodology was used. Patients with ESC-R-EC or susceptible E. coli isolated from blood or urine were recruited at six geographically dispersed tertiary hospitals in Australia and New Zealand. Epidemiological data was prospectively collected and bacteria were retained for analysis.

Results
In total, 182 patients (91 cases and 91 controls) were recruited. Multivariate logistic regression identified risk factors for ESC-R amongst E. coli including birth on the Indian subcontinent (OR=11.13, 2.17-56.98, p=0.003), urinary tract infection in the past year (per infection OR=1.430, 1.13-1.82, p=0.003), travel to South East Asia, China, Indian subcontinent, Africa and the Middle East (OR=3.089, 1.29-7.38, p=0.011), prior exposure to trimethoprim+/-sulfamethoxazole &/or an expanded-spectrum cephalosporin (OR=3.665, 1.30-10.35, p=0.014) and healthcare exposure in the previous six months (OR=3.16, 1.54-6.46, p=0.02).

Amongst our ESC-R-EC the blaCTX-M ESBLs was dominant (83% of ESC-R-EC), and the worldwide pandemic clone ST-131 was frequent (45% of ESC-R-EC).

Conclusion
In our low prevalence setting, ESC-R amongst community onset E. coli may be associated with both ‘export’ from healthcare facilities into the community and direct ‘import’ into the community from high-prevalence regions.

Gastrointestinal microbiota in autistic spectrum disorder

In this thesis, gut bacteria of children with autism were examined. The results provided new information and a compelling picture of the gut bacteria of children with autism and gastrointestinal symptomatology. The mechanisms that underlie gut dysfunction might involve factors like stress-induced changes in gut physiology associated with autism.

Does gender matter? A one year follow-up of autistic, attention and anxiety symptoms in high-functioning children with autism spectrum disorder

Gender differences in autism spectrum disorder (ASD) symptoms and associated problem behaviours over development may provide clues regarding why more males than females are diagnosed with ASD. Fifty-six high-functioning children with ASD, and 44 typically developing controls, half of the participants female, were assessed at baseline (aged 7–12 years) and one-year later, collecting measures of autism, attention and anxiety symptoms, school placement and support information. Findings indicated no gender differences in autistic symptoms. Males were more hyperactive and received more integration-aide support in mainstream schools, and females were more socially anxious. Overall, similar gender profiles were present across two time points. Lower hyperactivity levels in females might contribute to their under-identification. Implications are discussed using a biopsychosocial model of gender difference.

Neurobiology of schizophrenia spectrum disorders: The role of oxidative stress

Mitochondrial dysfunction and oxidative stress are increasingly implicated in the pathophysiology of schizophrenia. The brain is the body's highest energy consumer, and the glutathione system is the brain's dominant free radical scavenger. In the current paper, we review the evidence of central and peripheral nervous system anomalies in the oxidative defences of individuals with schizophrenia, principally involving the glutathione system. This is reflected by evidence of the manifold consequences of oxidative stress that include lipid peroxidation, protein carboxylation, DNA damage and apoptosis - all potentially part of the process of neuroprogression in the disorder. Importantly, oxidative stress is amenable to intervention. We consider the clinical potential of some possible interventions that help reduce oxidative stress, via augmentation of the glutathione system, particularly N-acetyl cysteine. We argue that a better understanding of the mechanisms and pathways underlying oxidative stress will assist in developing the therapeutic potential of this area.

Psychotropic medication use and autism spectrum disorders: caregiver and invidividual perspectives

 This thesis examined psychotropic medication use in Autism Spectrum Disorders in an Australian sample from caregiver and individual perspectives. This thesis found there is a clear need for collaboration between individuals with an ASD, their caregivers and professionals to ensure that psychotropic medication is used in an appropriate and transparent manner.