'Azospirillum brasilense' is a nitrogen fixing bacterium that has been shown to have various beneficial effects on plant growth and yield. Under normal conditions 'A. brasilense' exists in a motile flagellated form, which, under starvation or stress conditions, can undergo differentiation into an encapsulated, cyst-like form. Quantitative RT-PCR can be used to analyse changes in gene expression during this differentiation process. The accuracy of quantification of mRNA levels by qRT-PCR relies on the normalisation of data against stably expressed reference genes. No suitable set of reference genes has yet been described for A. brasilense. Here we evaluated the expression of ten candidate reference genes ('16S' 'rRNA', 'gapB', 'glyA', 'gyrA', 'proC', 'pykA', 'recA', 'recF', 'rpoD', and 'tpiA') in wild-type and mutant 'A. brasilense' strains under different culture conditions, including conditions that induce differentiation. Analysis with the software programs BestKeeper, NormFinder and GeNorm indicated that 'gyrA', 'glyA' and 'recA' are the most stably expressed reference genes in 'A. brasilense'. The results also suggested that the use of two reference genes ('gyrA and glyA') is sufficient for effective normalisation of qRT-PCR data.

Haemorrhagic enteritis virus (HEV) causes clinical haemorrhagic enteritis in young poults and/or subclinical immunosuppression which is often associated with colibacillosis. This disease is controlled with live vaccines worldwide, however, importation of HEV vaccines or cells that support HEV propagation are not permitted in Australia. A major experiment in isolators was conducted to test the safety and efficacy of a putative HEV vaccine. The study had a factorial design with four factors namely vaccination age (28 and 42 days of age), vaccine dose (0, 10⁵, 10⁶, 10⁷ genomic copies of HEV vaccine), challenge with HEV (yes, no) and vaccination-challenge interval (7, 21 or 42 days). A total of 315 poults were used providing 6-8 birds per treatment combination. Turkey growth rate, mortality, pathological findings, anti-HEV antibodies and viral load were examined. Vaccination lead to significant increases in anti HEV antibody over the following 2-4 weeks. Overall, vaccination with 10⁶ and 10⁷ was protective against increase in relative splenic weight and splenic viral load in challenged birds. Clinical haemorrhagic enteritis was not induced by any treatment but there was an increased incidence of airsacculitis in groups receiving either HEV vaccine or challenge virus compared to the negative control birds (25.8-29.3% vs. 9.4%, P < 0.05). Growth rate, mortality and relative bursal weight were unaffected by vaccination. This laboratory level study indicates that the putative vaccine is safe and likely to be efficacious, but may cause elevated levels of airsacculitis. These findings require confirmation in larger scale field trials.

Cortisol is a neurohormone released after a cascade response to stressors that begins in the hypothalamus, moves to the pituitary gland, and then to the adrenals, which secrete cortisol into the bloodstream as the final stage in this cascade. Cortisol affects many physiological functions, including vital anti‐inflammatory and immunosuppressive actions, as well as metabolism and homeostasis. Consequently, a basal concentration of cortisol is required at all times but may become immediately elevated in response to physical or mental stressors, usually returning to basal levels later. Underneath this immediate response to stressors, cortisol displays a diurnal variation so that concentrations are at their apex about 45 min after waking in the morning and decrease to their nadir in the early evening, a process referred to as the diurnal fluctuation in cortisol. However, this variation may become dysregulated by chronic stress and instead become consistently elevated, resulting in hypercortisolemia, which is characterized by an ongoing elevated concentration of cortisol in the bloodstream that is associated with pain, fatigue, increased risk of heart disease, and the symptoms of anxiety, muscle wastage, and hyperglycemia.

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition, characterised by impairments in social communication and the presence of restricted and repetitive behaviours, activities, or interests. ‘Sensory Features’ (SF) are a key symptom of ASD, and affect 90-95% of individuals with ASD, manifesting as atypical behavioural, neurological, and self-regulatory responses to sensory stimuli in the environment. Although the overt behavioural characteristics of SF in people with ASD have been extensively investigated, internal neurophysiological processes of SF in the ASD population have been minimally explored. One method of identifying these internal neurophysiological processes associated with SF is by using electroencephalography (EEG) to measure the brain’s electrical activity, and the ways that regions of the brain communicate or ‘connect’ with each other. There is a paucity of research investigating the direct relationship between SF and brain neural connectivity in children and adolescents with ASD, and this issue was made the focus of this research. Therefore, the current study aimed to investigate the relationship between SF in the ASD population and neural connectivity via (i) analyses of five different types of EEG connectivity measurements based on resting EEG data during eyes-closed and eyes-opened conditions, and (ii) analysis of Granger Causality on naturalistic audiovisual low-, medium-, and high-intensity stimulus conditions. The current study also aimed to investigate whether there was a relationship between age and Granger Causality connectivity indices in the ASD sample.

Forty-one male participants aged between 6 and 17 years, with an IQ of at least 70 and who were diagnosed with ASD took part in the current study. Connectivity analysis (using five methods: Coherence, Weighted Phase Lag Index-Debiased, Phase Locking Value, Granger Causality, and Phase Slope Index) and subsequent statistical analyses (using Pearson product moment and Spearman correlations, MANOVA, and paired samples t-tests) were conducted on EEG data from these participants.

Results indicated (i) minimal agreement between functional and effective connectivity for eyes-closed and eyes-opened conditions, (ii) significant (p < .05) deficits in connectivity between right hemisphere frontal and temporal brain regions, and a lack of significant correlations between this connectivity and Sensory Quadrant data collected on the Child Sensory Profile ( 2^nded.) for audiovisual stimuli, (iii) no significant differences in connectivity between frontal and occipital regions for all resting and stimulus conditions, and (iv) no significant correlations between age and neural connectivity in frontal, temporal, and occipital regions in response to audiovisual stimuli.

The results from this research add to the current literature and provide more evidence of atypical neuronal communication, especially between frontal and temporal regions, in regards to SF in male children and adolescents with ASD. Further research using a consistent connectivity method to analyse the associations between EEG connectivity and naturalistic experimental stimuli may provide more meaningful insights and suggestions for neurophysiological interventions to reduce the adverse effects of SF in individuals with ASD.

Purpose: Some prostate cancer (PCa) patients become clinically anxious or depressed after diagnosis and treatment. Some also show the physiological signs of chronic stress. However, there are currently no data describing how these particular patients might be identified at intake. This study tested the individual and combined predictive power of a psychological factor and a genetic factor as potential predictors of anxiety, depression, and chronic stress in a sample of PCa patients. Methods: Ninety-five PCa patients completed psychological inventories for anxiety, depression, and psychological resilience (PR) and also gave a saliva sample for cortisol and a mouthwash sample for genetic testing for the presence of the BDNF Val66Met polymorphism. Results: High PR patients had significantly lower anxiety and depression than low PR patients, but showed no significant differences in their salivary cortisol. Carriers of the Met allele of the BDNF Val66Met polymorphism had significantly higher salivary cortisol concentrations than patients who did not carry this allele. Conclusions: Each of these two factors may provide valuable information regarding the vulnerability of PCa patients to anxiety, depression, or chronic stress. Suggestions are made for their inclusion in clinical settings.

Forest fires are a regular occurrence in the Mediterranean basin. High severity fires and post-fire management can affect biological, chemical and physical properties of soil, including the composition and abundance of soil microbial communities. Salvage logging is a post-fire management strategy, which involves the removal of burnt wood from land after a fire. The main objective of this work was to evaluate the impact of post-fire salvage logging and microaggregation on soil microbial communities, specifically on the abundance of nitrogen cyclers and, thus, the potential of the soil for microbial nitrogen cycling. The abundance of nitrogen cyclers was assessed by quantification of microbial nitrogen cycling genes in soil DNA, including nifH (involved in nitrogen fixation), nirS/K and nosZ (involved in denitrification), amoA-B and amoA-Arch (involved in bacterial and archaeal nitrification, respectively). It was demonstrated that salvage logging reduced bacterial load post-fire when compared to tree retention control and resulted in significant changes to the abundance of functional bacteria involved in nitrogen cycling. Microbial gene pools involved in various stages of the nitrogen cycle were larger in control soil than in soil subjected to post-fire salvage logging and were significantly correlated with organic matter, available phosphorous, nitrogen and aggregate stability. The microaggregate fraction of the soil, which has been associated with greater organic carbon, was shown to be a hotspot for nitrogen cyclers particularly under salvage logging. The impact of post-fire management strategies on soil microbial communities needs to be considered in relation to maintaining ecosystem productivity, resilience and potential impact on climate change.

Purpose: Depression remains difficult to treat in all cases, and further investigation of the role of genetic and environmental factors may be valuable. This study was designed to investigate the association between the short (s) versus non-short (non-s) 5HTTLPR variants, presence of childhood stressors and recent life stressors, and depression, and to do so at two levels that would expose the associations between total depression scores and also individual depression items. Materials and methods: Two hundred and forty-nine volunteers from one of the Australian Electoral Office electorates covering a large rural land area completed a series of questionnaires about childhood and recent life stress and depression, and provided a buccal cell sample for genotyping the 5-HTTLPR polymorphism into s versus non-s carriers. Results: Although there were no significant differences in the depression scores of the s-carriers versus the non-s carriers, each subtype of the 5-HTTLPR polymorphism showed different patterns of association between childhood stress and depression symptoms, and between recent life stress and depression symptoms. Conclusion: Individualization of therapy for depression may be achieved through consideration of the specific associations that patients exhibit between life stress, 5-HTTLPR polymorphism, and depression symptomatology.

Children with Autism Spectrum Disorder (ASD) also often suffer from elevated stress and anxiety. These states can be measured via reports of behaviour (from self or others) or from physiological measures of stress, including the symptoms of Generalised Anxiety Disorder (GAD) and salivary cortisol, respectively. The use of these measures assumes a degree of reliability over time so that data from a specific period may be generalised to other periods. To measure the test-retest reliability of salivary cortisol and self-ratings of GAD in 27 high-functioning boys with ASD (M age = 12.1 yr., SD = 2.8 yr), samples were collected a mean of 2.4 yr. (SD = 0.5 yr) apart and analysed to test for the presence of a significant correlation within each variable over time. Results indicated that, although the concentrations of salivary cortisol increased over the period of the study, there was a significant correlation between the two measures of cortisol. GAD scores also showed a significant correlation over the period of the study. These findings suggest that both GAD and salivary cortisol data collected from boys with ASD may be reasonably inferred to represent fairly stable phenomena over time in research and clinical settings.

The comparative strength of the 5-HTTLPR polymorphism as a 'predictor' of depression after major stress, versus the 'protective' effect of psychological resilience (PR) against depression after major stress, was tested in a homogeneous sample of older men who had all received a diagnosis and treatment for prostate cancer. Results supported the association between PR and lower depression after stress, but did not support the association between the 5-HTTLPR and elevated depression after stress. Examination of PR at scale, factor, and item level identified the specific PR-related behaviour that was the most powerful predictor of low depression. These data suggest that the carriage of the short form of the 5-HTTLPR may negate the protective effect of PR against depression in these men, or that PR may nullify the depression vulnerability of this form of the 5-HTTLPR. These findings may explain some of the 'null' findings regarding the link between the 5-HTTLPR and depression in the wider literature by arguing for an interaction between these two factors in the association between major stress and depression.

Adhesion molecules are expressed by both adult and embryonic stem cells, with different classes of adhesion molecules involved in cell-membrane and intercellular contacts. In this study the expression of the adhesion molecule claudin-8 (CLDN8), a tight-junction protein, was investigated as a potential marker for undifferentiated spermatogonia in the bovine testis. We found that CLDN8 was expressed by both spermatogonia and a subset of Sertoli cells in the bovine testis. We also showed co-expression of GFRα1 in testis cells with CLDN8 and with 'Dolichos biflorus' agglutinin-fluorescein isothiocyanate (DBA-FITC) staining. We observed co-enrichment of spermatogonia and CLDN8-expressing Sertoli cells in DBA-FITC-assisted magnetic-activated cell sorting (MACS), an observation supported by results from fluorescence-activated cell sorting analysis, which showed CLDN8-expressing cells were over-represented in the MACS-positive cell fraction, leading to the hypothesis that CLDN8 may play a role in the spermatogonial stem-cell niche.