19325 research outputs found
Sort by
Regulatory T lymphocytes are associated with increased nasopharyngeal colonization in children
No full textObjectives: Regulatory T lymphocytes (Treg) have been linked to survival of commensal bacteria at mucosal sites, but their presence and role in chronic otitis media (COM) and their response to otopathogens has not been evaluated previously. We investigated the association between Treg lymphocytes and otopathogens in COM prone and non-COM prone children. Methods: Forty children, 2–7 years of age, scheduled for adenoidectomy were enrolled into COM (n = 20) or non-COM (n = 20) groups. Adenoid biopsy and nasopharyngeal aspirate bacteriology were assessed by conventional culture techniques. Peripheral blood and adenoid lymphocytes were stained with viability stain, monoclonal anti-CD19, anti-CD3, anti-CD4, anti-CD8, anti-CD25 and anti-CD127. Cells were stained intracellularly with monoclonal anti-FoxP3 and then quantified by flow cytometry. Results: Children with nasopharyngeal otopathogen-positive culture had significantly more circulating CD3+CD4+FoxP3+CD25hi+CD127lo+ lymphocytes (M = 4.4%) compared to culture-negative children (M = 3.1%, p = 0.005). Circulating CD19+ lymphocytes were significantly increased in children with positive Moraxella catarrhalis nasopharyngeal culture (M = 12.4%) compared to culture-negative children (M = 8.6%, p = 0.006). Adenoid-derived lymphocytes were not significantly different in children with any positive nasopharyngeal culture compared to negative culture. Lymphocyte subsets were not significantly different between COM and non-COM prone children. Conclusion: Clinically-detectable otopathogen nasopharyngeal culture is positively associated with Treg lymphocytes, potentially inducing suppressive effector responses to promote colonization and infection chronicity. This finding supports further investigation of Treg lymphocyte activity and influence on upper airway colonization of young children
Future climate change is predicted to affect the microbiome and condition of habitat-forming kelp
No full textClimate change is driving global declines of marine habitat-forming species through physiological effects and through changes to ecological interactions, with projected trajectories for ocean warming and acidification likely to exacerbate such impacts in coming decades. Interactions between habitat-formers and their microbiomes are fundamental for host functioning and resilience, but how such relationships will change in future conditions is largely unknown. We investigated independent and interactive effects of warming and acidification on a large brown seaweed, the kelp Ecklonia radiata, and its associated microbiome in experimental mesocosms. Microbial communities were affected by warming and, during the first week, by acidification. During the second week, kelp developed disease-like symptoms previously observed in the field. The tissue of some kelp blistered, bleached and eventually degraded, particularly under the acidification treatments, affecting photosynthetic efficiency. Microbial communities differed between blistered and healthy kelp for all treatments, except for those under future conditions of warming and acidification, which after two weeks resembled assemblages associated with healthy hosts. This indicates that changes in the microbiome were not easily predictable as the severity of future climate scenarios increased. Future ocean conditions can change kelp microbiomes and may lead to host disease, with potentially cascading impacts on associated ecosystems
Genome-wide selection footprints and deleterious variations in young Asian allotetraploid rapeseed
No full textBrassica napus (AACC, 2n=38) is an important oilseed crop grown worldwide. However, little is known about the population evolution of this species, the genomic difference between its major genetic groups, such as European and Asian rapeseed, and the impacts of historical large-scale introgression events on this young tetraploid. In this study, we reported the de novo assembly of the genome sequences of an Asian rapeseed (B. napus), Ningyou 7 and its four progenitors and compared these genomes with other available genomic data from diverse European and Asian cultivars. Our results showed that Asian rapeseed originally derived from European rapeseed but subsequently significantly diverged, with rapid genome differentiation after hybridization and intensive local selective breeding. The first historical introgression of B. rapa dramatically broadened the allelic pool but decreased the deleterious variations of Asian rapeseed. The second historical introgression of the double-low traits of European rapeseed (canola) has reshaped Asian rapeseed into two groups (double-low and double-high), accompanied by an increase in genetic load in the double-low group. This study demonstrates distinctive genomic footprints and deleterious SNP (Single Nucleotide Polymorphism) variants for local adaptation by recent intra- and interspecies introgression events and provides novel insights for understanding the rapid genome evolution of a young allopolyploid crop
Leaning into the discomfort and embracing the disruption: a Freirean approach to (de)colonised social work teaching in Australia
No full textThis paper uses an autoethnographic Freirean approach to theorise how white power moves in universities, and to speak to the pedagogical challenges (and successes) that I have encountered as a scholar of colour teaching in predominantly white universities in Australia and my various attempts to decolonise my teaching. While in social work education we are expected to teach students to become agents of social change, we confront a whitewashed curriculum that often ignores or undermines Indigenous ways of knowing – transmitting and focusing mostly on knowledge that is deemed important for ‘white Australia’. A colonised education system promotes and produces harmful dualities of power and inequality. As such, there is a need to re-examine the current curricula and introduce spaces of learning that are not just simply ‘inclusive and multicultural’, but also deeply transformational and liberating in the sense that Paulo Freire envisioned
The effect of dissolved nickel and copper on the adult coral Acropora muricata and its microbiome
No full textThe potential impacts of mining activities on tropical coastal ecosystems are poorly understood. In particular, limited information is available on the effects of metals on scleractinian corals which are foundation species that form vital structural habitats supporting other biota. This study investigated the effects of dissolved nickel and copper on the coral Acropora muricata and its associated microbiota. Corals collected from the Great Barrier Reef were exposed to dissolved nickel (45, 90, 470, 900 and 9050 μg Ni/L) or copper (4, 11, 32 and 65 μg Cu/L) in flow through chambers at the National Sea Simulator, Townsville, Qld, Australia. After a 96-h exposure DNA metabarcoding (16S rDNA and 18S rDNA) was undertaken on all samples to detect changes in the structure of the coral microbiome. The controls remained healthy throughout the study period. After 36 h, bleaching was only observed in corals exposed to 32 and 65 μg Cu/L and very high nickel concentrations (9050 μg Ni/L). At 96 h, significant discolouration of corals was only observed in 470 and 900 μg Ni/L treatments, the highest concentrations tested. While high concentrations of nickel caused bleaching, no changes in the composition of their microbiome communities were observed. In contrast, exposure to copper not only resulted in bleaching, but altered the composition of both the eukaryote and bacterial communities of the coral\u27s microbiomes. Our findings showed that these effects were only evident at relatively high concentrations of nickel and copper, reflecting concentrations observed only in extremely polluted environments. Elevated metal concentrations have the capacity to alter the microbiomes which are inherently linked to coral health
Adnyamathanha archives and colonial ruins: The UNSETTLED Project
No full textThe exhibition UNSETTLED: Colonial Ruin in the Flinders Ranges is a critical examination of settler-colonial nostalgia in the Flinders Ranges, within an artistic context. The project is underpinned by a partnership with the State Library of South Australia (SLSA) and the Adnyamathanha Traditional Lands Association, and it was exhibited at the SLSA in Adelaide, March–May 2017. Spread across the SLSA Institute Gallery, on the videowall in the Spence Walkway, and on the Storywall outdoor architectural projection, the exhibition consists of a range of photographic and video art works alongside portrait images of Adnyamathanha people taken in 1937 at the Nepabunna Mission by Charles Mountford, and video interviews with descendants of the people in the portraits. In this article, we discuss the components of the exhibition and its artistic and curatorial rationale and, in so doing, propose a series of responses to the key question that guided our activities on this project: What strategies and practices can non-Aboriginal artists employ to question the dominance of settler-colonial nostalgia in Australia
A realist evaluation of a regional Dementia Health Literacy Project
No full textBackground: A Dementia Health Literacy Project was undertaken in the north coast region of NSW, Australia, after it was identified as having a high prevalence of dementia. A Dementia Support Kit was produced with service user engagement to provide useful information to people with dementia and their families.
Objective: To evaluate the Dementia Health Literacy Project using a realist evaluation framework.
Setting and participants: The setting was the region of the north coast of New South Wales. Eight people diagnosed with dementia and their carers, 13 members of social groups of older people in the local area, and 22 local GPs and other health-care and service providers participated in this study.
Results: Two context-mechanism-outcome configurations were identified: (a) codesign workshops where the stakeholders’ opinions were equally valued (context) led service users to feel listened to and prompted them to provide feedback (mechanism) to develop a practical resource that they would use (outcome); and (b) use of health professionals to distribute the resources (context) that they consider useful and valuable (mechanism) resulted in the target audience receiving the resources (outcome).
Discussion and conclusions: The Dementia Health Literacy Project produced a Dementia Support Kit that is likely to provide locally relevant and useful information for people with dementia and their carers. The results highlight the value of the codesign approach in producing and disseminating dementia health literacy resources. Further evaluation is required to confirm the impact of the Kit over time on service users’ behaviour and consequently on their health outcomes
Bromoperoxidase producing bacillus spp. Isolated from the hypobranchial glands of a muricid mollusc are capable of tyrian purple precursor biogenesis
No full textThe secondary metabolite Tyrian purple, also known as shellfish purple and royal purple, is a dye with historical importance for humans. The biosynthetic origin of Tyrian purple in Muricidae molluscs is not currently known. A possible role for symbiotic bacteria in the production of tyrindoxyl sulphate, the precursor to Tyrian purple stored in the Australian species, Dicathais orbita, has been proposed. This study aimed to culture bacterial symbionts from the purple producing hypobranchial gland, and screen the isolates for bromoperoxidase genes using molecular methods. The ability of bromoperoxidase positive isolates to produce the brominated indole precursor to Tyrian purple was then established by extraction of the culture, and analysis by liquid chromatography–mass spectrometry (LC–MS). In total, 32 bacterial isolates were cultured from D. orbita hypobranchial glands, using marine agar, marine agar with hypobranchial gland aqueous extracts, blood agar, thiosulphate citrate bile salts sucrose agar, and cetrimide agar at pH 7.2. These included 26 Vibrio spp., two Bacillus spp., one Phaeobacter sp., one Shewanella sp., one Halobacillus sp. and one Pseudoalteromonas sp. The two Bacillus species were the only isolates found to have coding sequences for bromoperoxidase enzymes. LC–MS analysis of the supernatant and cell pellets from the bromoperoxidase producing Bacillus spp. cultured in tryptone broth, supplemented with KBr, confirmed their ability to produce the brominated precursor to Tyrian purple, tyrindoxyl sulphate. This study supports a potential role for symbiotic Bacillus spp. in the biosynthesis of Tyrian purple
Intimations of masculinities among young male sports bettors
No full textThis study explored intimations of masculinities within narratives of young Australian men who bet regularly on sport. Qualitative data collected from white, heterosexual Australian men aged 18–34 revealed their sports betting as characterised by four interrelated intimations of masculinities. Sports betting was portrayed as masculine leisure with the young men’s sports betting interest often influenced by older males and male peers. A foundation and context for social interactions among male peers, sports betting provided a backdrop for formative masculine identity construction. An entrenched male peer group norm, sports betting success produced cultural capital and subsequent social status by virtue of analytic skill, risktaking and boisterous, competitive social interactions. However, sports betting was widely perceived as stigmatised leisure capable of prejudicing the young men’s prospective or existing intimate relationships with women. The young men negotiated this dilemma by adopting softer projections of masculinity in which sports betting was concealed in the presence of their spouse or prospective female partners. We therefore theorise sports betting as an augmentation to sport as a bastion for the construction of heteronormative masculinity, whilst lending further support to conceptualisations of masculine identities as plural and fluid