Biosecurity and invasive animal research

Murdoch University prides itself on its fundamental and applied research, as demonstrated by our work in biosecurity and invasive animals. Our researchers work across terrestrial and aquatic systems directly with industry and community partners

Petroleum geochemistry of the Amadeus Basin

Amber Jarrett, Dianne Edwards, Chris Boreham and David McKird

Detection and quantitation of synthetic cannabinoid receptor agonists in infused papers from prisons in a constantly evolving illicit market

© 2020 John Wiley & Sons, Ltd. Drug misuse in prisons contributes to increased disruption and violence and negatively impacts prisoner safety, rehabilitation, and recovery. Synthetic cannabinoid receptor agonists (SCRAs), colloquially known as “spice”, are infused into papers and are of particular concern in a prison setting where they are commonly vaped. Methods for the qualitative and quantitative analysis of SCRA infused papers, including impurity profiling, were developed using gas chromatography–mass spectrometry (GC–MS) with qualitative confirmation by ultra high pressure liquid chromatography with photodiode array and quadrupole time of flight mass spectrometry detection (UPLC-PDA-QToF-MS) and applied to 354 individual seized paper samples originating from 168 seizures from three Scottish prisons. Of these samples, 41% (146 samples from 101 seizures) contained at least one SCRA and multiple SCRAs were detected on 23% of these papers. Concentrations ranged from < 0.05–1.17 mg/cm2 paper, representing the first reported quantitative data for SCRA infused papers. An evolution in the SCRAs detected was demonstrated; 5F-MDMB-PINACA (5F-ADB) predominated until late 2018, after which time 5F-MDMB-PICA and 4F-MDMB-BINACA became increasingly more prevalent, followed by the arrival of MDMB-4en-PINACA in June 2019. Concentration mapping data from two seized paper samples demonstrated that SCRA concentrations across larger papers were highly variable (0.47–2.38 mg/cm2 paper) making consistent dosing by users, and representative sampling by laboratory analysts, difficult. Near real-time qualitative and quantitative information on SCRAs circulating in prisons acts as an early warning system for SCRAs emerging on the wider illicit market, inform the methods used to detect them and limit supply, and provide information to support harm reduction measures

A common neural system mediating two different forms of social judgement

Background: A wide range of neuropsychiatric conditions, including schizophrenia and autistic spectrum disorder (ASD), are associated with impairments in social function. Previous studies have shown that individuals with schizophrenia and ASD have deficits in making a wide range of social judgements from faces, including decisions related to threat (such as judgements of approachability) and decisions not related to physical threat (such as judgements of intelligence). We have investigated healthy control participants to see whether there is a common neural system activated during such social decisions, on the basis that deficits in this system may contribute to the impairments seen in these disorders. Method: We investigated the neural basis of social decision making during judgements of approachability and intelligence from faces in 24 healthy participants using functional magnetic resonance imaging (fMRI). We used conjunction analysis to identify common brain regions activated during both tasks. Results: Activation of the amygdala, medial prefrontal cortex, inferior prefrontal cortex and cerebellum was seen during performance of both social tasks, compared to simple gender judgements from the same stimuli. Task-specific activations were present in the dorsolateral prefrontal cortex in the intelligence task and in the inferior and middle temporal cortex in the approachability task. Conclusions: The present study identified a common network of brain regions activated during the performance of two different forms of social judgement from faces. Dysfunction of this network is likely to contribute to the broad-ranging deficits in social function seen in psychiatric disorders such as schizophrenia and ASD

Virus diseases of annual medics.

Trial 87A19, 87MT50 Persistence of AMV in annual medic swards. In 1990, the fourth year of this trial, although the medic plants were numerous the burr medic swards at Avondale grew poorly and weeds were widespread in the plots, especially long storkbill, flatweed and grasses. Poor growth was due to nodulation failure caused by low soil pH (5.3 in water). Hardly any medic plants were left in the Zodiac medic plot at Avondale while a few remained at Mt. Barker. Location: Avondale and Mt. Barker. Trial 88A21 Effect of AMV on the productivity of burr medic swards after cropping, regeneration and grazing. Location: Avondale 88A21 was allowed to regenerate in 1990 following cropping with barley in 1989. It was hard grazed in summer and autumn (first germination was in February following summer rains). Then, at the beginning of June sheep were excluded and the buffers resown with oats. It was subsequently grazed again from mid-August to early-September (3 weeks) but as grazing was uneven all plots were mown (4 cm cutting height) at the end of this period to even them up. Trial 90A5 Effect of AMV on the productivity of newly sown burr medic swards. Location: Avondale 90A5 was sown in early June and grazed portions of plots were grazed from August 15 - September 7. There were major differences in the plots due to seed source. With all three cultivars the infected seed stocks produced more vigorous growth. This was visible from July to September in ungrazed portions of plots but was largely removed by grazing. When the phosphorus content of the seed stocks sown was determined it was higher in infected than healthy seed. Seed phosphorus seemed the most likely cause of better growth of infected seed

Biology, invasion and management of the agricultural invader: Fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae)

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is native to the Americas. It has rapidly invaded 47 African countries and 18 Asian countries since the first detection of invasion into Nigeria and Ghana in 2016. It is regarded as a super pest based on its host range (at least 353 host plants), its inherent ability to survive in a wide range of habitats, its strong migration ability, high fecundity, rapid development of resistance to insecticides/viruses and its gluttonous characteristics. The inherently superior biological characteristics of FAW contribute to its invasiveness. Integrated pest management (IPM) of FAW has relied on multiple applications of monitoring and scouting, agricultural control, chemical pesticides, viral insecticides, sex attractants, bio-control agents (parasitoids, predators and entomopathogens) and botanicals. Knowledge gaps remain to be filled to: (1) understand the invasive mechanisms of S. frugiperda; (2) understand how to prevent its further spread and (3) provide better management strategies. This review summarizes the biological characters of FAW, their association with its invasiveness and IPM strategies, which may provide further insights for future management

Experimental summary 1988

1. Disease complexes in wheat field screening trials. 2. Glasshouse screening for wheat leaf disease resistance. 3. Effect of phosphate, stand density and Rovral on Pleiochaeta setosa in lupins. 4. Genotype and rvral for Pleichaeta setosa in lupins. 5. Control of Septoria in early sown wheat. 6. Controlling Pyrenophora graminea leaf stripe in barley. 7. Effect of environment on leaf stripe in barley. 8. Unusual seed quality problems

Set shifting and reversal learning in patients with bipolar disorder or schizophrenia

Background. Bipolar disorder and schizophrenia have both been associated with deficits in extra-dimensional set shifting (EDS). Deficits in reversal learning (RL) have also been shown in schizophrenia but not in bipolar disorder. This study sought to assess the specificity of these findings in a direct comparison of clinically stable patients with each disorder. Method. The intra-dimensional/extra-dimensional (IDED) set-shifting task, part of the Cambridge Neuropsychological Test Automated Battery (CANTAB), was administered to 30 patients with schizophrenia, 47 with bipolar disorder and a group of 44 unaffected controls. EDS and RL errors were compared between the groups and related to measures of current and past psychiatric symptoms and medication. Results. Both groups of patients with schizophrenia or bipolar disorder made more EDS and RL errors than controls. Neither measure separated the two disorders, even when the analysis was restricted to euthymic patients. No relationship was found with prescribed medication. Conclusions. Patients with bipolar disorder or schizophrenia show common deficits in EDS and RL. These deficits do not seem to be attributable to current symptoms and are consistent with disrupted networks involving the ventral prefrontal cortex

Neurocognition in individuals at high familial risk of mood disorders with or without subsequent onset of depression

Background Neurocognitive performance deficits have been observed in mood disorder patients and their unaffected relatives and may therefore qualify as endophenotypes. However, the precise time course of neurocognitive deficits has not been studied so that it is unknown whether neurocognitive abnormalities reflect the early effects of familial vulnerability to mood disorders or if they emerge at illness onset. Method A neuropsychological test battery was administered at baseline and after a 2-year follow-up interval in 111 initially unaffected young adults at high familial risk of mood disorders and 93 healthy controls (HC). During the follow-up period, 20 high-risk subjects developed major depressive disorder (HR-MDD), with the remainder remaining well (HR-well). Linear mixed-effects models were used to investigate differences and longitudinal changes in the domains of attentional processing, working memory, verbal learning and memory, and cognitive flexibility. Results Reduced long delay verbal memory and extradimensional set-shifting performance across both time points were found in the HR-well group relative to controls. The HR-MDD group displayed decreased extradimensional set-shifting abilities across both time points as compared with the HC group only. There were no significant performance differences between the two high-risk groups. Conclusions Reduced verbal memory and cognitive flexibility are familial trait markers for vulnerability to mood disorders in individuals with a close family history of bipolar disorder. Both neurocognitive performance deficits appear to be relatively stable over a 2-year time period and do not appear to be linked to the onset of MDD. These findings support their use as stable quantitative endophenotypes for mood disorders

SARS-CoV-2 infection, clinical features and outcome of COVID-19 in United Kingdom nursing homes.

OBJECTIVES: To understand SARS-Co-V-2 infection and transmission in UK nursing homes in order to develop preventive strategies for protecting the frail elderly residents. METHODS: An outbreak investigation involving 394 residents and 70 staff, was carried out in 4 nursing homes affected by COVID-19 outbreaks in central London. Two point-prevalence surveys were performed one week apart where residents underwent SARS-CoV-2 testing and had relevant symptoms documented. Asymptomatic staff from three of the four homes were also offered SARS-CoV-2 testing. RESULTS: Overall, 26% (95% CI 22-31) of residents died over the two-month period. All-cause mortality increased by 203% (95% CI 70-336) compared with previous years. Systematic testing identified 40% (95% CI 35-46) of residents as positive for SARS-CoV-2, and of these 43% (95% CI 34-52) were asymptomatic and 18% (95% CI 11-24) had only atypical symptoms; 4% (95% CI -1 to 9) of asymptomatic staff also tested positive. CONCLUSIONS: The SARS-CoV-2 outbreak in four UK nursing homes was associated with very high infection and mortality rates. Many residents developed either atypical or had no discernible symptoms. A number of asymptomatic staff members also tested positive, suggesting a role for regular screening of both residents and staff in mitigating future outbreaks