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Nucleotide-binding oligomerization domain, leucine rich repeat containing X1 (NLRX1) is a negative regulator of the nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) pathway, with a significant role in the context of inflammation. Altered expression of NLRX1 is prevalent in inflammatory diseases leading to interest in NLRX1 as a drug target. There is a lack of structural information available for NLRX1 as only the leucine-rich repeat domain of NLRX1 has been crystallised. This lack of structural data limits progress in understanding function and potential druggability of NLRX1. We have modelled full-length NLRX1 by combining experimental, homology modelled and AlphaFold2 structures. The full-length model of NLRX1 was used to explore protein dynamics, mutational tolerance and potential functions. We identified a new RNA binding site in the previously uncharacterized N-terminus, which served as a basis to model protein-RNA complexes. The structure of the adenosine triphosphate (ATP) binding domain revealed a potential catalytic functionality for the protein as a member of the ATPase Associated with Diverse Cellular Activity family of proteins. Finally, we investigated the interactions of NLRX1 with small molecule activators in development, revealing a binding site that has not previously been discussed in literature. The model generated here will help to catalyse efforts towards creating new drug molecules to target NLRX1 and may be used to inform further studies on functionality of NLRX1.

AbstractToll-like receptor (TLR) innate immunity signalling protects against pathogens, but excessive or prolonged signalling contributes to a range of inflammatory conditions. Structural information on the TLR cytoplasmic TIR (Toll/interleukin-1 receptor) domains and the downstream adaptor proteins can help us develop inhibitors targeting this pathway. The small molecule o-vanillin has previously been reported as an inhibitor of TLR2 signalling. To study its mechanism of action, we tested its binding to the TIR domain of the TLR adaptor MAL/TIRAP (MALTIR). We show that o-vanillin binds to MALTIR and inhibits its higher-order assembly in vitro. Using NMR approaches, we show that o-vanillin forms a covalent bond with lysine 210 of MAL. We confirm in mouse and human cells that o-vanillin inhibits TLR2 but not TLR4 signalling, independently of MAL, suggesting it may covalently modify TLR2 signalling complexes directly. Reactive aldehyde-containing small molecules such as o-vanillin may target multiple proteins in the cell.

Abstract Background Increased airway NLRP3 inflammasome-mediated IL-1β responses may underpin severe neutrophilic asthma. However, whether increased inflammasome activation is unique to severe asthma, is a common feature of immune cells in all inflammatory types of severe asthma, and whether inflammasome activation can be therapeutically targeted in patients, remains unknown. Objective To investigate the activation and inhibition of inflammasome-mediated IL-1β responses in immune cells from patients with asthma. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from patients with non-severe (n = 59) and severe (n = 36 stable, n = 17 exacerbating) asthma and healthy subjects (n = 39). PBMCs were stimulated with nigericin or lipopolysaccharide (LPS) alone, or in combination (LPS + nigericin), with or without the NLRP3 inhibitor MCC950, and the effects on IL-1β release were assessed. Results PBMCs from patients with non-severe or severe asthma produced more IL-1β in response to nigericin than those from healthy subjects. PBMCs from patients with severe asthma released more IL-1β in response to LPS + nigericin than those from non-severe asthma. Inflammasome-induced IL-1β release from PBMCs from patients with severe asthma was not increased during exacerbation compared to when stable. Inflammasome-induced IL-1β release was not different between male and female, or obese and non-obese patients and correlated with eosinophil and neutrophil numbers in the airways. MCC950 effectively suppressed LPS-, nigericin-, and LPS + nigericin-induced IL-1β release from PBMCs from all groups. Conclusion An increased ability for inflammasome priming and/or activation is a common feature of systemic immune cells in both severe and non-severe asthma, highlighting inflammasome inhibition as a universal therapy for different subtypes of disease.

Holocaust museums around the world are distinctive in their emphasis on educational missions premised on the idea of “never again”, a deep belief that increasing public awareness of the history and contemporary significance of the Holocaust – the mass murder of six million European Jews by the Nazi regime during World War Two – can prevent the future recurrence of such events. In the Australian context, tens of thousands of school students visit Holocaust museums every year to participate in learning programs designed to impart powerful historical and moral lessons about the Holocaust, its antecedent conditions, and its ongoing relevance. The aspirations attached to these programs and the scale at which they are delivered stand in stark contrast to the lack of empirical evidence to support their efficacy. This research protocol describes an extensive four-year research study designed to evaluate the presumed linear relationship between Holocaust education programs and ethical, moral, and affective learning that leads to durable attitudinal and behavioural change. Funded through the Australian Research Council’s Linkage Projects scheme, the study will assess the impact of Holocaust museums’ education programs on high school students from diverse demographics, including the extent to which participation influences the views and actions of young people in relation to racial and identity-based discrimination. The research design is longitudinal and transdisciplinary, integrating qualitative, quantitative, and participatory techniques across three case studies. By strategically employing rapid ethnographic assessment procedures, archival research, analysis of museum representational practices, surveys, and visual research methods, we will examine both the educational intent behind Holocaust education programs and their actual impacts on a large sample of Australian Year 10 students. We expect the results of the research to be used by our project partners to develop Holocaust education programs that effectively engage students on cognitive and affective levels.

The exhibition Metaphors and Allegories: Superstudio, Firenze opened at the Israel Museum in Jerusalem in 1982. Initially conceived by curator Izzika Gaon as an opportunity to communicate the Florentine group’s ‘special method of working and thinking’ through existing work, Metaphors and Allegories ultimately initiated a much more direct conversation with the Israeli public through the display of a design for the Western Wall Plaza undertaken by Adolfo Natalini and David Palterer. Drawing on archival material and interviews, this paper positions this scheme as a provocation that sought to use its position within the museum to reflect on and respond to a series of ongoing political and social tensions within Israeli society. A temporary display intended to be seen within the walls of the Israel Museum, Natalini and Palterer’s project for the Western Wall Plaza intertwines various views of the past that inform the differing conceptions of the wall’s purpose, challenging a singular, statist vision for the site.

Mevalonate kinase deficiency (MKD) is characterized by recurrent fevers and flares of systemic inflammation, caused by biallelic loss-of-function mutations in MVK. The underlying disease mechanisms and triggers of inflammatory flares are poorly understood because of the lack of in vivo models. We describe genetically modified mice bearing the hypomorphic mutation p.Val377Ile (the commonest variant in patients with MKD) and amorphic, frameshift mutations in Mvk. Compound heterozygous mice recapitulated the characteristic biochemical phenotype of MKD, with increased plasma mevalonic acid and clear buildup of unprenylated GTPases in PBMCs, splenocytes, and bone marrow. The inflammatory response to LPS was enhanced in compound heterozygous mice and treatment with the NLRP3 inflammasome inhibitor MCC950 prevented the elevation of circulating IL-1β, thus identifying a potential inflammasome target for future therapeutic approaches. Furthermore, lines of mice with a range of deficiencies in mevalonate kinase and abnormal prenylation mirrored the genotype-phenotype relationship in human MKD. Importantly, these mice allowed the determination of a threshold level of residual enzyme activity, below which protein prenylation is impaired. Elevated temperature dramatically but reversibly exacerbated the deficit in the mevalonate pathway and the defective prenylation in vitro and in vivo, highlighting increased body temperature as a likely trigger of inflammatory flares.

The COVID-19 pandemic has strained the resources of the world's healthcare systems. Most individuals with neurodevelopmental disabilities (NDDs) experience significant mental health issues and face substantial barriers in accessing appropriate supports which have been exacerbated during the pandemic. It is unknown the extent to which COVID-19 impacted the demand for and effectiveness of inpatient care for those with NDDs. The impact of COVID-19 on the number of admissions of youth with NDDs to pediatric inpatient psychiatry units, as well as their functioning and length of stay during the first two years of the pandemic was analyzed using Bayesian structural time series models. Admission data of youth with NDDs from four pediatric inpatient units in Alberta, Canada (n = 2144) was examined. Inpatient admissions of youth with NDDs significantly increased following the onset of the pandemic. Compared to the period prior to the pandemic, patients with NDDs had significantly worse overall functioning and received fewer days of treatment. These findings highlight the need for increased resources to support the mental health needs of this vulnerable population and are consistent with other studies in the general population examining the utilization of inpatient psychiatric units during the pandemic.

The Bacillus haemolytic enterotoxin haemolysin BL has been shown to activate the NLRP3 inflammasome. Here the authors show that a non-haemolytic enterotoxin (NHE) from B. cereus can also activate the NLRP3 inflammasome with a similar mechanism of lytic pore formation.

The NLRP3 inflammasome has emerged as a central immune regulator that senses virulence factors expressed by microbial pathogens for triggering inflammation. Inflammation can be harmful and therefore this response must be tightly controlled. The mechanisms by which immune cells, such as macrophages, discriminate benign from pathogenic microbes to control the NLRP3 inflammasome remain poorly defined. Here we used live cell imaging coupled with a compendium of diverse clinical isolates to define how macrophages respond and activate NLRP3 when faced with the human yeast commensal and pathogen Candida albicans. We show that metabolic competition by C. albicans, rather than virulence traits such as hyphal formation, activates NLRP3 in macrophages. Inflammasome activation is triggered by glucose starvation in macrophages, which occurs when fungal load increases sufficiently to outcompete macrophages for glucose. Consistently, reducing Candida's ability to compete for glucose and increasing glucose availability for macrophages tames inflammatory responses. We define the mechanistic requirements for glucose starvation-dependent inflammasome activation by Candida and show that it leads to inflammatory cytokine production, but it does not trigger pyroptotic macrophage death. Pyroptosis occurs only with some Candida isolates and only under specific experimental conditions, whereas inflammasome activation by glucose starvation is broadly relevant. In conclusion, macrophages use their metabolic status, specifically glucose metabolism, to sense fungal metabolic activity and activate NLRP3 when microbial load increases. Therefore, a major consequence of Candida-induced glucose starvation in macrophages is activation of inflammatory responses, with implications for understanding how metabolism modulates inflammation in fungal infections.

Background Aortic aneurysms and dissections are highly lethal diseases for which an effective treatment strategy is critically needed to prevent disease progression. The nucleotide‐binding oligomerization domain–like receptor pyrin domain containing 3 (NLRP3)–caspase‐1 inflammasome cascade was recently shown to play an important role in aortic destruction and disease development. In this study, we tested the effects of MCC950, a potent, selective NLRP3 inhibitor, on preventing aortic destruction and aortic aneurysm and dissection formation. Methods and Results In a model of sporadic aortic aneurysm and dissection induced by challenging wild‐type mice with a high‐fat, high‐cholesterol diet and angiotensin II infusion, MCC950 treatment significantly inhibited challenge‐induced aortic dilatation, dissection, and rupture in different thoracic and abdominal aortic segments in both male and female mice. Aortic disease reduction by MCC950 was associated with the prevention of NLRP3–caspase‐1 upregulation, smooth muscle cell contractile protein degradation, aortic cell death, and extracellular matrix destruction. Further investigation revealed that preventing matrix metallopeptidase 9 (MMP‐9) expression and activation in macrophages is an important mechanism underlying MCC950's protective effect. We found that caspase‐1 directly activated MMP‐9 by cleaving its N‐terminal inhibitory domain. Moreover, the genetic knockdown of Nlrp3 or Casp‐1 in mice or treatment of mice with MCC950 diminished the challenge‐induced N‐terminal cleavage of MMP‐9, MMP‐9 activation, and aortic destruction. Conclusions Our findings suggest that the NLRP3–caspase‐1 inflammasome directly activates MMP‐9. Targeting the inflammasome with MCC950 is a promising approach for preventing aortic destruction and aortic aneurysm and dissection development.

Summary: Pro-inflammatory caspase-1 is a key player in innate immunity. Caspase-1 processes interleukin (IL)-1β and IL-18 to their mature forms and triggers pyroptosis. These caspase-1 functions are linked to its enzymatic activity. However, loss-of-function missense mutations in CASP1 do not prevent autoinflammation in patients, despite decreased IL-1β production. In vitro data suggest that enzymatically inactive caspase-1 drives inflammation via enhanced nuclear factor κB (NF-κB) activation, independent of IL-1β processing. Here, we report two mouse models of enzymatically inactive caspase-1-C284A, demonstrating the relevance of this pathway in vivo. In contrast to Casp1−/− mice, caspase-1-C284A mice show pronounced hypothermia and increased levels of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and IL-6 when challenged with lipopolysaccharide (LPS). Caspase-1-C284A signaling is RIP2 dependent and mediated by TNF-α but independent of the NLRP3 inflammasome. LPS-stimulated whole blood from patients carrying loss-of-function missense mutations in CASP1 secretes higher amounts of TNF-α. Taken together, these results reveal non-canonical caspase-1 signaling in vivo. : Reinke et al. show that enzymatically inactive caspase-1-C284A mediates non-canonical caspase-1 signaling. This pathway is RIP2 dependent and mediated by TNF-α but independent from IL-1 cytokines. Keywords: caspase-1, Rip2, NF-κB, TNF-α, non-canonical caspase-1 signaling, enzymatic activity

Summary: Inflammasomes promote immunity to microbial pathogens by regulating the function of IL-1-family cytokines such as IL-18 and IL-1β. However, the roles for inflammasomes during parasitic helminth infections remain unclear. We demonstrate that mice and humans infected with gastrointestinal nematodes display increased IL-18 secretion, which in Trichuris-infected or worm antigen-treated mice and in macrophages co-cultured with Trichuris antigens or exosome-like vesicles was dependent on the NLRP3 inflammasome. NLRP3-deficient mice displayed reduced pro-inflammatory type 1 cytokine responses and augmented protective type 2 immunity, which was reversed by IL-18 administration. NLRP3-dependent suppression of immunity partially required CD4+ cells but was apparent even in Rag1−/− mice that lack adaptive immune cells, suggesting that NLRP3 influences both innate and adaptive immunity. These data highlight a role for NLRP3 in limiting protective immunity to helminths, suggesting that targeting the NLRP3 inflammasome may be an approach for limiting the disease burden associated with helminth infections. : Inflammasomes can protect us against infections with bacteria and viruses, but Alhallaf et al. now find that these inflammasomes may also actually prevent our immune system from being able to fight parasitic worm infections. Keywords: inflammasome, NLRP3, IL-18, helminth, exosomes, immunopathology, goblet cells

Background: Many speech sound disorder (SSD) interventions with a long-term evidence base are 'new' to clinical practice, and the role of services in supporting or constraining capacity for practice change is underexplored. Innovations from implementation science may offer solutions to this research-practice gap but have not previously been applied to SSD. Aim: To explain variation in speech and language therapy service capacity to implement new SSD interventions. Methods & Procedures: We conducted an intensive, case-based qualitative study with 42 speech and language therapists (SLTs) in three NHS services (n = 39) and private practice (n = 3) in Scotland. We explored therapists' diverse experiences of SSD practice change through individual interviews (n = 28) or self-generated paired (n = 2) or focus groups (n = 3). A theoretical framework (Normalization Process Theory) helped us understand how the service context contributed to the way therapists engaged with different practice changes. Outcomes & Results: We identified six types ('cases') of practice change, two of which involved the new SSD interventions. We focus on these two cases ('Transforming' and 'Venturing') and use Normalization Process Theory's Cognitive participation construct to explain implementation (or not) of new SSD interventions in routine practice. Therapists were becoming aware of the new interventions through knowledge brokers, professional networks and an intervention database. In the Transforming case, new SSD interventions for selected children were becoming part of local routine practice. Transforming was the result of a favourable service structure, a sustained and supported 'push' that made implementation of the new interventions a service priority, and considerable collective time to think about doing it. 'Venturing' happened where the new SSD interventions were not a service priority. It involved individual or informal groups of therapists trying out or using one or more of the new interventions with selected children within the constraints of their service context. Conclusions & implications: New, evidence-based SSD interventions may be challenging to implement in routine practice because they have in common a need for therapists who understand applied linguistics and can be flexible with service delivery. Appreciating what it really takes to do routine intervention differently is vital for managers and services who have to make decisions about priorities for implementation, along with realistic plans for resourcing and supporting it.

Australian Holocaust museums are at a crossroads regarding their exhibitions and educational programming. Originally survivor driven initiatives, they now face the dual challenge of negotiating the loss of the survivor generation and interpreting the goals of Holocaust education in light of their absence. To do so, they must confront the question of what Holocaust education seeks to achieve and, most poignantly, whether it can continue to speak to succeeding generations of Australian student and general visitors, now far removed from the event both historically and geographically. This article examines how this moment of intergenerational change has and is being negotiated at the Sydney Jewish Museum through reflection on the development and implementation of its newest permanent exhibition, "The Holocaust and Human Rights." An explicit attempt to bring the intimate histories of the survivors into dialogue with broader, more universalistic concerns, the exhibition provides a microcosm of both the potential and problematics such ventures entail.

This paper investigates the role of teacher agency for those who were trained in using an innovative Geographic Information Systems (GIS) approach and incorporated GIS into their teaching. While national curricula increasingly emphasise STEM and sustainability approaches, there has been limited analysis of how teachers can bring new software, including GIS, and new approaches into the classroom. Through an evaluation of a teaching initiative "5*S: Space, Surveyors and Students -- STEM and the Sustainable Development Goals" designed to bring GIS technology, satellite data, and the Sustainable Development Goals (SDGs) into classrooms as activities and resources for teachers and students in Ireland, we examine how teachers can introduce new teaching strategies and platforms into their classrooms. In interviews and a focus group, teachers expressed eagerness for GIS teaching resources for the classroom and identified effective ways they were able to draw on their own teaching philosophy in introducing new concepts around sustainability and STEM education in the classroom. We argue that teacher agency and autonomy play an important role in the ability and development of teachers, departments, and schools to bring new approaches and GIS into the classroom, and we identify key learnings from teachers who were able to utilise the 5*S resources.

Ischemia-reperfusion (I/R)-related disorders, such as stroke, myocardial infarction, and peripheral vascular disease, are among the most frequent causes of disease and death. Tissue injury or death may result from the initial ischemic insult, primarily determined by the magnitude and duration of the interruption in blood supply and then by the subsequent reperfusion-induced damage. Various in vitro and in vivo models are currently available to study I/R mechanism in the brain and other tissues. However, thus far, no in ovo I/R model has been reported for understanding the I/R mechanisms and for faster drug screening. Here, we developed an in ovo Hook model of I/R by occluding and releasing the right vitelline artery of a chick embryo at 72 h of development. To validate the model and elucidate various underlying survival and death mechanisms, we employed imaging (Doppler blood flow imaging), biochemical, and blotting techniques and evaluated the cell death mechanism: autophagy and inflammation caused by I/R. In conclusion, the present model is useful in parallel with established in vitro and in vivo I/R models to understand the mechanisms of I/R development and its treatment.

To understand how extracellular vesicle (EV) subtypes differentially activate monocytes, a series of in vitro studies were performed. We found that plasma-EVs biased monocytes toward an M1 profile. Culturing monocytes with granulocyte-, monocyte-, and endothelial-EVs induced several pro-inflammatory cytokines. By contrast, platelet-EVs induced TGF-β and GM-CSF, and red blood cell (RBC)-EVs did not activate monocytes in vitro. The scavenger receptor CD36 was important for binding of RBC-EVs to monocytes, while blockade of CD36, CD163, CD206, TLR1, TLR2, and TLR4 did not affect binding of plasma-EVs to monocytes in vitro. To identify mortality risk factors, multiple soluble factors and EV subtypes were measured in patients’ plasma at intensive care unit admission. Of 43 coagulation factors and cytokines measured, two were significantly associated with mortality, tissue plasminogen activator and cystatin C. Of 14 cellular markers quantified on EVs, 4 were early predictors of mortality, including the granulocyte marker CD66b. In conclusion, granulocyte-EVs have potent pro-inflammatory effects on monocytes in vitro. Furthermore, correlation of early granulocyte-EV levels with mortality in critically ill patients provides a potential target for intervention in management of the pro-inflammatory cascade associated with critical illness.