19683 research outputs found
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Optimization of mouse kidney digestion protocols for single-cell applications
No full textAbstract:Single-cell technologies such as flow cytometry and single-cell RNA sequencing have allowed for comprehensive characterization of the kidney cellulome. However, there is a disparity in the various protocols for preparing kidney single-cell suspensions. We aimed to address this limitation by characterizing kidney cellular heterogeneity using three previously published single-cell preparation protocols. Single-cell suspensions were prepared from male and female C57BL/6 kidneys using the following kidney tissue dissociation protocols: a scRNAseq protocol (P1), a multi-tissue digestion kit from Miltenyi Biotec (P2), and a protocol established in our laboratory (P3). Following dissociation, flow cytometry was used to identify known major cell types including leukocytes (myeloid and lymphoid), vascular cells (smooth muscle and endothelial), nephron epithelial cells (intercalating, principal, proximal, and distal tubule cells), podocytes, and fibroblasts. Of the protocols tested, P2 yielded significantly less leukocytes and type B intercalating cells compared with the other techniques. P1 and P3 produced similar yields for most cell types; however, endothelial and myeloid-derived cells were significantly enriched using P1. Significant sex differences were detected in only two cell types: granulocytes (increased in males) and smooth muscle cells (increased in females). Future single-cell studies that aim to enrich specific kidney cell types may benefit from this comparative analysis. NEW & NOTEWORTHY This study is the first to evaluate published single-cell suspension preparation protocols and their ability to produce high-quality cellular yields from the mouse kidney. Three single-cell digestion protocols were compared and each produced significant differences in kidney cellular heterogeneity. These findings highlight the importance of the digestion protocol when using single-cell technologies. This study may help future single-cell science research by guiding researchers to choose protocols that enrich certain cell types of interest. flow cytometry; renal; single-cell RNA sequencing; tissue dissociation.</p
Unveiling the Digital Divide: Public and Private Spaces on Social Media in the Saudi Context
No full textA thesis submitted in total fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Humanities and Social Sciences, La Trobe University, Victoria, Australia.</p
Direct C4 and C2 C-H Amination of Heteroarenes Using I(III) Reagents via a Cross Azine Coupling
No full textAminated nitrogen heterocycles are valuable motifs across numerous chemical industries, perhaps most notably in small molecule drug discovery. While numerous strategies for installing nitrogen atoms onto azaarenes exist, most require prefunctionalization and methods for direct C-H amination are almost entirely limited to position C2. Herein, we report a method for the direct C2 and C4 C-H amination of fused azaarenes via in situ activation with a bispyridine-ligated I(III) reagent, [(Py)2IPh]2OTf, or Py-HVI. Unlike commonly used N-oxide chemistry, the method requires no preoxidation of the azaarene and provides unprecedented direct access to C4 amination products. The resulting N-heterocyclic pyridinium salts can be isolated via simple trituration. The free amine can be liberated under mild Zincke aminolysis, or the amination and cleavage can be telescoped to a one-pot process. The scope of the method is broad; the conditions are mild and operationally simple, and the aminated products are produced in good to excellent yields. Computational studies provide insights into the mechanism of activation, which involves an unusual direct nucleophilic functionalization of an I(III) ligand, as well as a kinetic basis for the observed C2 and C4 amination products.</p
Landscape burning facilitated Aboriginal migration into Lutruwita/Tasmania 41,600 years ago
No full textThe establishment of Tasmanian Palawa/Pakana communities ~40 thousand years ago (ka) was achieved by the earliest and farthest human migrations from Africa and necessitated migration into high-latitude Southern Hemisphere environments. The scarcity of high-resolution paleoecological records during this period, however, limits our understanding of the environmental effects of this pivotal event, particularly the importance of using fire as a tool for habitat modification. We use two paleoecological records from the Bass Strait islands to identify the initiation of anthropogenic landscape transformation associated with ancestral Palawa/Pakana land use. People were living on the Tasmanian/Lutruwitan peninsula by ~41.6 ka using fire to penetrate and manipulate forests, an approach possibly used in the first migrations across the last glacial landscape of Sahul.</p
Toward designing human intervention studies to prevent osteoarthritis after knee injury: A report from an interdisciplinary OARSI 2023 workshop
No full textObjective: The global impact of osteoarthritis is growing. Currently no disease modifying osteoarthritis drugs/therapies exist, increasing the need for preventative strategies. Knee injuries have a high prevalence, distinct onset, and strong independent association with post-traumatic osteoarthritis (PTOA). Numerous groups are embarking upon research that will culminate in clinical trials to assess the effect of interventions to prevent knee PTOA despite challenges and lack of consensus about trial design in this population. Our objectives were to improve awareness of knee PTOA prevention trial design and discuss state-of-the art methods to address the unique opportunities and challenges of these studies. Design: An international interdisciplinary group developed a workshop, hosted at the 2023 Osteoarthritis Research Society International Congress. Here we summarize the workshop content and outputs, with the goal of moving the field of PTOA prevention trial design forward. Results: Workshop highlights included discussions about target population (considering risk, homogeneity, and possibility of modifying osteoarthritis outcome); target treatment (considering delivery, timing, feasibility and effectiveness); comparators (usual care, placebo), and primary symptomatic outcomes considering surrogates and the importance of knee function and symptoms other than pain to this population. Conclusions: Opportunities to test multimodal PTOA prevention interventions across preclinical models and clinical trials exist. As improving symptomatic outcomes aligns with patient and regulator priorities, co-primary symptomatic (single or aggregate/multidimensional outcome considering function and symptoms beyond pain) and structural/physiological outcomes may be appropriate for these trials. To ensure PTOA prevention trials are relevant and acceptable to all stakeholders, future research should address critical knowledge gaps and challenges.</p
Internalized Sexual Stigma and Mental Health Outcomes for Gay, Lesbian, and Bisexual Asian Americans: The Moderating Role of Guilt and Shame
No full textThe literature unequivocally demonstrates that lesbian, gay, and bisexual (LGB) individuals experience disproportionate mental health and social wellbeing impacts. Here, we respond to recent calls for research in the field of sexual minority health to better understand why various overlapping and intersecting identities can further drive health disparities. In this paper, we focus on the specific intersections of ethnicity and sexuality for Asian LGB individuals and the role of internalized stigma in driving poorer mental health outcomes for this group. We recruited 148 LGB Asian participants residing in the United States (Mage = 22.82 years, SD = 4.88) to participate in our online cross-sectional survey in which we collected data on their internalized stigma, levels of guilt and shame about their sexuality, and measures of depression, anxiety, and distress. Contrary to our predictions, there were no bivariate relationships between internalized sexual stigma and any of the mental health outcomes. However, a parallel mediation analysis revealed that guilt, but not shame, mediates the relationship between internalized sexual stigma and all mental health outcomes (depression, anxiety, and stress) for LGB Asian American individuals. This research highlights the important of exploring additional variables that may exacerbate of protect against poor mental health for individuals with multiple intersecting identities.</p
Estimates and predictors of alcohol-related harm to intimate partners in Australia An analysis of a nationally representative survey
No full textAims: This study explores the prevalence and predictors reported by men and women of alcohol-related intimate partner violence (ARIPV), that is, verbal abuse, physical abuse, and being put in fear by intimate partners when partners were under the influence of alcohol. Methods: Cross-sectional analysis of the 2019 Australian National Drug Strategy Household Survey included 22,015 respondents (9,804 men, and 12,211 women) aged 14 years or older. The prevalence of ARIPV in the past year is described, and the ARIPV predictors were analysed using chi-square tests and logistic regressions, overall and separately for men and women. Results: An estimated 3.4% of the Australian adult population (4.7% women, 2.1% men) reported any ARIPV in 2019. The prevalence of ARIPV was higher among participants who were women, middle-aged (35–44 years), had a certificate or diploma, were less advantaged, were divorced, separated, or widowed, single with dependents, living in more regional and remote areas, and undertook heavy episodic drinking (HED) weekly or less often. Age, marital status, household composition, and any HED predicted any ARIPV for women, while higher education levels and weekly or monthly HED were significant for men. Discussion and conclusions: Women were twice as likely to report intimate partner violence (IPV) from their male partner when they were under the influence of alcohol, as were men. The findings underline that interventions are needed to address IPV from intoxicated partners.</p
“Take It Easy, I’ll Tell You if There’s Something Wrong”: Young Cisgender Heterosexual Men and Sexual Communication During Casual Sex in Australia
No full textIntroduction: Calls for consent and masculinity workshops in Australian schools aim to address sexual violence by cisgender heterosexual men. However, little research explores how these men understand and practise sexual consent in the face of these calls. This study investigates how young men in Australia navigate consent in casual encounters. Methods: Thirty semi-structured qualitative interviews were conducted with young men living in Australia between May and September in 2021. Participants were asked about their dating and sexual practices, as well as their understanding and navigation of verbal and body language in relation to sexual communication and consent. The findings were analysed using interpretive phenomenological analysis techniques. Results: Findings note tensions between contradictory expectations within sexual encounters. This includes (1) determining genuine or coerced interest, (2) their awareness of women’s body language but desiring verbal communication, and (3) their awareness of their own body language but perceiving this as not being assertive enough. Conclusions: Men are acutely aware of the body language and verbal cues indicating sexual interest, enjoyment, and rejection for consent. They navigate complex relationships, managing new expectations concerning women’s bodily autonomy and traditional gendered norms in sex and intimacy. Policy Implications: New concerns regarding the place of ambiguity and exploration within young men and women’s sexual encounters are emerging from critiques of sexual consent education. Policy and practice should pay greater attention to embedding skills for navigating these ambiguities rather than assuming people as fully knowing beings.</p
Arts integration in an early childhood education setting: The role of the teacher
No full textAbstract: This paper presents research undertaken in an early learning centre in Melbourne, Australia. The first of four case studies, it explores how arts practices and pedagogies can be embedded within and integrated across an early childhood centre curriculum, with a focus on the role of the teacher in achieving this. Twenty-one children aged 3- to-5 years and three experienced early childhood teachers chose to participate in the study. A broad range of ethnographic data was collected over a 10-week period, including digital artefacts, interviews and conversations, teachers’ documentation, and observation notes. Inductive methods were used to analyse the data. The findings revealed that the role of the teacher in integrating the arts is complex and multifaceted, with nine pedagogical themes identified. Using examples from the data to illustrate how the themes presented in the classroom, the findings are framed by three overarching themes: planning for learning, responsive teaching, and documenting learning.</p
Long-term Vegetation Changes on Alpine Summits in Response to Global Drivers of Change
No full textA thesis submitted in total fulfilment of the requirements for the degree of Master of Science to the School of Agriculture, Biomedicine and Environment, La Trobe University, Victoria, Australia.</p