A liver immune rheostat regulates CD8 T cell immunity in chronic HBV infection.

Chronic hepatitis B virus (HBV) infection affects 300 million patients worldwide1,2, in whom virus-specific CD8 T cells by still ill-defined mechanisms lose their function and cannot eliminate HBV-infected hepatocytes3-7. Here we demonstrate that a liver immune rheostat renders virus-specific CD8 T cells refractory to activation and leads to their loss of effector functions. In preclinical models of persistent infection with hepatotropic viruses such as HBV, dysfunctional virus-specific CXCR6+ CD8 T cells accumulated in the liver and, as a characteristic hallmark, showed enhanced transcriptional activity of cAMP-responsive element modulator (CREM) distinct from T cell exhaustion. In patients with chronic hepatitis B, circulating and intrahepatic HBV-specific CXCR6+ CD8 T cells with enhanced CREM expression and transcriptional activity were detected at a frequency of 12-22% of HBV-specific CD8 T cells. Knocking out the inhibitory CREM/ICER isoform in T cells, however, failed to rescue T cell immunity. This indicates that CREM activity was a consequence, rather than the cause, of loss in T cell function, further supported by the observation of enhanced phosphorylation of protein kinase A (PKA) which is upstream of CREM. Indeed, we found that enhanced cAMP-PKA-signalling from increased T cell adenylyl cyclase activity augmented CREM activity and curbed T cell activation and effector function in persistent hepatic infection. Mechanistically, CD8 T cells recognizing their antigen on hepatocytes established close and extensive contact with liver sinusoidal endothelial cells, thereby enhancing adenylyl cyclase-cAMP-PKA signalling in T cells. In these hepatic CD8 T cells, which recognize their antigen on hepatocytes, phosphorylation of key signalling kinases of the T cell receptor signalling pathway was impaired, which rendered them refractory to activation. Thus, close contact with liver sinusoidal endothelial cells curbs the activation and effector function of HBV-specific CD8 T cells that target hepatocytes expressing viral antigens by means of the adenylyl cyclase-cAMP-PKA axis in an immune rheostat-like fashion.

The Ecological Separation of Deer and Domestic, Feral and Native Mammals in Tropical Northern Australia-A Review.

We explored the ecological and historical factors that led to formation of the unique guild of native and introduced mammalian herbivores between 5 and 1000 kg in northern Australia. Following the disappearance of large native herbivores about 46 kya, and until the arrival of Europeans and their livestock, the only herbivorous mammals were mid-sized endemic marsupial macropods, which continued to utilise the same vegetation as their much larger former neighbours. Only one species of contemporary native herbivore has an adult bodyweight approaching 100 kg, and for the past 150-200 years, the total biomass of introduced domestic and wild vertebrate herbivores has massively exceeded that of native herbivorous species. We conclude that the current guild of native and introduced mammalian herbivores differentially utilises the landscape ecologically. However, climate- and anthropogenically related changes due to fire, drought, flooding, predation and introduced weeds are likely to have significant impacts on the trajectory of their relative ecological roles and populations. Given their differing ecological and dietary characteristics, against this backdrop, it is unclear what the potential impact of the dispersal of deer species could have in northern Australia. We hence focus on whether sufficient knowledge exists against which the potential impacts of the range expansion of three deer species can be adequately assessed and have found a dearth of supporting evidence to inform appropriate sustainable management. We identify suitable research required to fill the identified knowledge gaps.

Temperature Dependence of the Mechanical Dissipation of Gallium Bonds for Use in Gravitational Wave Detectors.

The mirror suspensions in gravitational wave detectors demand low mechanical loss jointing to ensure good enough detector performance and to enable the detection of gravitational waves. Hydroxide catalysis bonds have been used in the fused silica suspensions of the GEO600, Advanced LIGO, and Advanced Virgo detectors. Future detectors may use cryogenic cooling of the mirror suspensions and this leads to a potential change of mirror material and suspension design. Other bonding techniques that could replace or be used alongside hydroxide catalysis bonding are of interest. A design that incorporates repair scenarios is highly desirable. Indeed, the mirror suspensions in KAGRA, which is made from sapphire and operated at cryogenic temperatures, have used a combination of hydroxide catalysis bonding and gallium bonding. This Letter presents the first measurements of the mechanical loss of a gallium bond measured between 10 K and 295 K. It is shown that the loss, which decreases with temperature down to the level of (1.8±0.3)×10^{-4} at 10 K, is comparable to that of a hydroxide catalysis bond.

Non-canonical substrate recognition by the human WDR26-CTLH E3 ligase regulates prodrug metabolism.

The yeast glucose-induced degradation-deficient (GID) E3 ubiquitin ligase forms a suite of complexes with interchangeable receptors that selectively recruit N-terminal degron motifs of metabolic enzyme substrates. The orthologous higher eukaryotic C-terminal to LisH (CTLH) E3 complex has been proposed to also recognize substrates through an alternative subunit, WDR26, which promotes the formation of supramolecular CTLH E3 assemblies. Here, we discover that human WDR26 binds the metabolic enzyme nicotinamide/nicotinic-acid-mononucleotide-adenylyltransferase 1 (NMNAT1) and mediates its CTLH E3-dependent ubiquitylation independently of canonical GID/CTLH E3-family substrate receptors. The CTLH subunit YPEL5 inhibits NMNAT1 ubiquitylation and cellular turnover by WDR26-CTLH E3, thereby affecting NMNAT1-mediated metabolic activation and cytotoxicity of the prodrug tiazofurin. Cryoelectron microscopy (cryo-EM) structures of NMNAT1- and YPEL5-bound WDR26-CTLH E3 complexes reveal an internal basic degron motif of NMNAT1 essential for targeting by WDR26-CTLH E3 and degron mimicry by YPEL5's N terminus antagonizing substrate binding. Thus, our data provide a mechanistic understanding of how YPEL5-WDR26-CTLH E3 acts as a modulator of NMNAT1-dependent metabolism.

"COVID-19 - A Perfect Storm": A Qualitative Exploration of Residential Care Facility Managers Perspectives on the Psychosocial Impacts of COVID-19.

Growing evidence highlights the negative impact of managing the COVID-19 pandemic on the wellbeing of the healthcare workforce, including in the aged care sector. We undertook a qualitative study during the pandemic's third year to explore the psychosocial impacts on nine managers of residential care facilities (RCFs) across metropolitan and rural New South Wales, the largest state in Australia. Four themes were identified: (1) Increased pressure on maintaining aged care services, (2) Increased responsibility on RCF managers, (3) Psychosocial impacts due to accumulating pressures, and (4) Experience of beneficial supports. COVID-19 compounded pre-pandemic sector challenges and added new stressors. While resilient and resourceful, RCF managers experienced workplace stress and burnout, which may affect quality of resident care and impact on staff retention. There is a need for more investment to effectively support staff, and research to identify optimal psychosocial and management supports.

Spontaneous Lesions of Endangered Geriatric Julia Creek Dunnarts (Sminthopsis douglasi, Archer 1979) with Emphasis in Reproductive Pathology.

Julia Creek dunnarts are an endangered species of carnivorous marsupials and the focus of multiple conservation strategies involving significant resources such as captive breeding programs. Despite the relevance for conservation, no study to date has focused on evaluating geriatric diseases in dunnarts. This study describes the pathology findings in a group of one wild and thirty-five captive-born, mostly geriatric Julia Creek dunnarts that failed to produce offspring over multiple breeding periods. A total of 20 females and 16 males were submitted for a postmortem examination, with ages ranging from 9 to 42 and 12 to 42 months for females and males, respectively. Of these, 10 had unremarkable findings. The most common condition in females was cystic glandular hyperplasia (n = 8), typical of hormonal dysregulation profiles in senescence, particularly hyperestrogenism. Rarely, cutaneous disease represented by unidentified dermal round cell infiltrates was observed in females (n = 2). Primary reproductive hormonal dysregulation was also suspected in males diagnosed with testicular degeneration, aspermatogenesis and/or atrophy (n = 3). Cutaneous round cell infiltrates, possibly compatible with epitheliotropic lymphomas, were seen in males (n = 3), and 2/3 affected males also had concurrent testicular degeneration or atrophy, indicating male sex could be a predictor for lymphoid neoplasia in aged dunnarts, especially in individuals with concurrent testosterone-luteinizing hormone dysregulation as it occurs in gonadectomized animals. The role of an underlying viral etiology is also explored. This study is the first to describe major spontaneous diseases in endangered aged Julia Creek dunnarts, providing an important understanding of senescence and geriatric diseases within a conservation context.

Skraban-Deardorff intellectual disability syndrome-associated mutations in WDR26 impair CTLH E3 complex assembly.

Patients with Skraban-Deardorff syndrome (SKDEAS), a neurodevelopmental syndrome associated with a spectrum of developmental and intellectual delays and disabilities, harbor diverse mutations in WDR26, encoding a subunit of the multiprotein CTLH E3 ubiquitin ligase complex. Structural studies revealed that homodimers of WDR26 bridge two core-CTLH E3 complexes to generate giant, hollow oval-shaped supramolecular CTLH E3 assemblies. Additionally, WDR26 mediates CTLH E3 complex binding to subunit YPEL5 and functions as substrate receptor for the transcriptional repressor HBP1. Here, we mapped SKDEAS-associated mutations on a WDR26 structural model and tested their functionality in complementation studies using genetically engineered human cells lacking CTLH E3 supramolecular assemblies. Despite the diversity of mutations, 15 of 16 tested mutants impaired at least one CTLH E3 complex function contributing to complex assembly and interactions, thus providing first mechanistic insights into SKDEAS pathology.

Hand Surgery Fellowship Case Minimums: History and Design.

In the 1960s, the American Society for Surgery of the Hand embarked on an endeavor to improve and standardize the educational experience in hand surgery. By the 1980s, numerous programs existed across the country with the Accreditation Council for Graduate Medical Education formally recognizing orthopedic surgery-based fellowships in 1985 and plastic surgery-based fellowships in 1986. In order to sit for what was then termed the Certificate of Additional Qualification examination, applicants had to demonstrate performance of a specific number of procedures while in practice. Borrowing from this theme, the Accreditation Council for Graduate Medical Education began to analyze programs according to the relative proportion of cases done by fellows at individual institutions compared to national trends. Beginning in 2019 and working collaboratively with the Accreditation Council for Graduate Medical Education, the Hand Fellowship Director's Association has since modified the methods by which programs are evaluated, pivoting away from comparative percentages to the establishment of case minimums. The development of this process has been iterative with the resultant outcome being an evaluation system that focuses on educational quality and technical proficiency over sheer numerical volume.

Histone lysine demethylase 4 family proteins maintain the transcriptional program and adrenergic cellular state of MYCN-amplified neuroblastoma.

Neuroblastoma with MYCN amplification (MNA) is a high-risk disease that has a poor survival rate. Neuroblastoma displays cellular heterogeneity, including more differentiated (adrenergic) and more primitive (mesenchymal) cellular states. Here, we demonstrate that MYCN oncoprotein promotes a cellular state switch in mesenchymal cells to an adrenergic state, accompanied by induction of histone lysine demethylase 4 family members (KDM4A-C) that act in concert to control the expression of MYCN and adrenergic core regulatory circulatory (CRC) transcription factors. Pharmacologic inhibition of KDM4 blocks expression of MYCN and the adrenergic CRC transcriptome with genome-wide induction of transcriptionally repressive H3K9me3, resulting in potent anticancer activity against neuroblastomas with MNA by inducing neuroblastic differentiation and apoptosis. Furthermore, a short-term KDM4 inhibition in combination with conventional, cytotoxic chemotherapy results in complete tumor responses of xenografts with MNA. Thus, KDM4 blockade may serve as a transformative strategy to target the adrenergic CRC dependencies in MNA neuroblastomas.

Implementing recommended COVID-19 public health measures in the era of living with COVID-19: Experiences of residential aged care facility managers in New South Wales, Australia.

OBJECTIVES: To understand residential aged care facility (the facility) managers' perspectives on implementing public health measures (the measures) in their facilities in terms of barriers, facilitators and suggestions for improvement, after three years of the COVID-19 pandemic. METHODS: Nine managers of the facilities without an active COVID-19 outbreak across New South Wales, Australia, representing metropolitan and rural locations, diverse facility size and star quality rating were interviewed (April-June 2023) and data qualitatively analysed. RESULTS: Broader policy context, the need to balance the measures with resident well-being, facility-built infrastructure and mask fatigue were reported as barriers to implementation. Workplace policies, cultural embedding and local innovations were reported as facilitators. Suggested strategies included recommending the measures consistent with temporal COVID-19 risk; government agencies improving communication about the measures; mandatory staff vaccination; and simplified reporting requirements. CONCLUSIONS: We recommend that relevant government agencies develop a single source of formalised, endorsed, up-to-date advice for the sector-specific COVID-19 information and communications; streamline outbreak notification and reporting requirements; and improve consultation with the sector.

Single-Macromolecule Studies of Eukaryotic Genomic Maintenance.

Genomes are self-organized and self-maintained as long, complex macromolecules of chromatin. The inherent heterogeneity, stochasticity, phase separation, and chromatin dynamics of genome operation make it challenging to study genomes using ensemble methods. Various single-molecule force-, fluorescent-, and sequencing-based techniques rooted in different disciplines have been developed to fill critical gaps in the capabilities of bulk measurements, each providing unique, otherwise inaccessible, insights into the structure and maintenance of the genome. Capable of capturing molecular-level details about the organization, conformational changes, and packaging of genetic material, as well as processive and stochastic movements of maintenance factors, a single-molecule toolbox provides an excellent opportunity for collaborative research to understand how genetic material functions in health and malfunctions in disease. In this review, we discuss novel insights brought to genomic sciences by single-molecule techniques and their potential to continue to revolutionize the field-one molecule at a time.

Doa10/MARCH6 architecture interconnects E3 ligase activity with lipid-binding transmembrane channel to regulate SQLE.

Transmembrane E3 ligases play crucial roles in homeostasis. Much protein and organelle quality control, and metabolic regulation, are determined by ER-resident MARCH6 E3 ligases, including Doa10 in yeast. Here, we present Doa10/MARCH6 structural analysis by cryo-EM and AlphaFold predictions, and a structure-based mutagenesis campaign. The majority of Doa10/MARCH6 adopts a unique circular structure within the membrane. This channel is established by a lipid-binding scaffold, and gated by a flexible helical bundle. The ubiquitylation active site is positioned over the channel by connections between the cytosolic E3 ligase RING domain and the membrane-spanning scaffold and gate. Here, by assaying 95 MARCH6 variants for effects on stability of the well-characterized substrate SQLE, which regulates cholesterol levels, we reveal crucial roles of the gated channel and RING domain consistent with AlphaFold-models of substrate-engaged and ubiquitylation complexes. SQLE degradation further depends on connections between the channel and RING domain, and lipid binding sites, revealing how interconnected Doa10/MARCH6 elements could orchestrate metabolic signals, substrate binding, and E3 ligase activity.

Titania Mixed with Silica: A Low Thermal-Noise Coating Material for Gravitational-Wave Detectors.

Coating thermal noise is one of the dominant noise sources in current gravitational wave detectors and ultimately limits their ability to observe weaker or more distant astronomical sources. This Letter presents investigations of TiO_{2} mixed with SiO_{2} (TiO_{2}:SiO_{2}) as a coating material. We find that, after heat treatment for 100 h at 850 °C, thermal noise of a highly reflective coating comprising of TiO_{2}:SiO_{2} and SiO_{2} reduces to 76% of the current levels in the Advanced LIGO and Advanced Virgo detectors-with potential for reaching 45%, if we assume the mechanical loss of state-of-the-art SiO_{2} layers. Furthermore, those coatings show low optical absorption of <1 ppm and optical scattering of ≲5 ppm. Notably, we still observe excellent optical and thermal noise performance following crystallization in the coatings. These results show the potential to meet the parameters required for the next upgrades of the Advanced LIGO and Advanced Virgo detectors.

Activity-based profiling of cullin-RING E3 networks by conformation-specific probes.

The cullin-RING ubiquitin ligase (CRL) network comprises over 300 unique complexes that switch from inactive to activated conformations upon site-specific cullin modification by the ubiquitin-like protein NEDD8. Assessing cellular repertoires of activated CRL complexes is critical for understanding eukaryotic regulation. However, probes surveying networks controlled by site-specific ubiquitin-like protein modifications are lacking. We developed a synthetic antibody recognizing the active conformation of NEDD8-linked cullins. Implementing the probe to profile cellular networks of activated CUL1-, CUL2-, CUL3- and CUL4-containing E3s revealed the complexes responding to stimuli. Profiling several cell types showed their baseline neddylated CRL repertoires vary, and prime efficiency of targeted protein degradation. Our probe also unveiled differential rewiring of CRL networks across distinct primary cell activation pathways. Thus, conformation-specific probes can permit nonenzymatic activity-based profiling across a system of numerous multiprotein complexes, which in the case of neddylated CRLs reveals widespread regulation and could facilitate the development of degrader drugs.

Th2-dependent disappearance and phenotypic conversion of mouse alveolar macrophages.

Alveolar macrophages (alvMs) play an important role for maintenance of lung function by constant removal of cellular debris in the alveolar space. They further contribute to defense against microbial or viral infections and limit tissue damage during acute lung injury. alvMs arise from embryonic progenitor cells, seed the alveoli before birth, and have life-long self-renewing capacity. However, recruited monocytes may also help to restore the alvM population after depletion caused by toxins or influenza virus infection. At present, the population dynamics and cellular plasticity of alvMs during allergic lung inflammation is poorly defined. To address this point, we used a mouse model of Aspergillus fumigatus-induced allergic lung inflammation and observed that Th2-derived IL-4 and IL-13 caused almost complete disappearance of alvMs. This effect required STAT6 expression in alvMs and also occurred in various other settings of type 2 immunity-mediated lung inflammation or administration of IL-4 complexes to the lung. In addition, Th2 cells promoted conversion of alvMs to alternatively activated macrophages and multinucleated giant cells. Given the well-established role of alvMs for maintenance of lung function, this process may have implications for resolution of inflammation and tissue homeostasis in allergic asthma.

Embedding Aboriginal cultural governance, capacity, perspectives and leadership into a local Public Health Unit Incident Command System during COVID-19 in New South Wales, Australia.

This case study describes the development and implementation of a governance structure that prioritised First Nations peoples in a local public health Incident Command System activated for the COVID-19 pandemic response in New South Wales, Australia. Using lessons learnt from past pandemics and planning exercises, public health leaders embedded an approach whereby First Nations peoples determined and led community and culturally informed pandemic control strategies and actions.In March 2020, First Nations governance was embedded into the local public health emergency response to COVID-19 in the Hunter New England region of New South Wales, Australia, enabling First Nations staff and community members to actively participate in strategic and operational decision-making with the objective of minimising COVID-19-related risks to First Nations peoples and communities. The model provided cultural insight and oversight to the local COVID-19 response; strengthened and advanced First Nations leadership; increased the First Nations public health workforce; led the development of First Nations disease surveillance strategies; and supported working groups to appropriately respond to local needs and priorities. This model demonstrates the feasibility of reframing a standard Incident Command System to embed and value First Nations principles of self-determination and empowerment to appropriately plan and respond to public health emergencies.

IL4i1 and IDO1: Oxidases that control a tryptophan metabolic nexus in cancer.

Regulated tryptophan metabolism by immune cells has been associated with the promotion of tolerance and poor outcomes in cancer. The main focus of research has centered on local tryptophan depletion by IDO1, an intracellular heme-dependent oxidase that converts tryptophan to formyl-kynurenine. This is the first step of a complex pathway supplying metabolites for de novo NAD+ biosynthesis, 1-carbon metabolism, and a myriad of kynurenine derivatives of which several act as agonists of the arylhydrocarbon receptor (AhR). Thus, cells that express IDO1 deplete tryptophan while generating downstream metabolites. We now know that another enzyme, the secreted L-amino acid oxidase IL4i1 also generates bioactive metabolites from tryptophan. In tumor microenvironments, IL4i1 and IDO1 have overlapping expression patterns, especially in myeloid cells, suggesting the two enzymes control a network of tryptophan-specific metabolic events. New findings about IL4i1 and IDO1 have shown that both enzymes generate a suite of metabolites that suppress oxidative cell death ferroptosis. Thus, within inflammatory environments, IL4i1 and IDO1 simultaneously control essential amino acid depletion, AhR activation, suppression of ferroptosis, and biosynthesis of key metabolic intermediates. Here, we summarize the recent advances in this field, focusing on IDO1 and IL4i1 in cancer. We speculate that while inhibition of IDO1 remains a viable adjuvant therapy for solid tumors, the overlapping effects of IL4i1 must be accounted for, as potentially both enzymes may need to be inhibited at the same time to produce positive effects in cancer therapy.

Seasonal resource selection of an arboreal habitat specialist in a human-dominated landscape: A case study using red panda.

Human-dominated landscapes provide heterogeneous wildlife habitat. Conservation of habitat specialists, like red pandas Ailurus fulgens, inhabiting such landscapes is challenging. Therefore, information on resource use across spatial and temporal scales could enable informed-decision making with better conservation outcomes. We aimed to examine the effect of geo-physical, vegetation, and disturbance variables on fine-scale habitat selection of red pandas in one such landscape. We equipped 10 red pandas with GPS collars in eastern Nepal in 2019 and monitored them for 1 year. Our analysis was based on a generalized-linear-mixed model. We found the combined effect of geo-physical, vegetation, and disturbance variables resulted in differences in resource selection of red pandas and that the degree of response to these variables varied across seasons. Human disturbances, especially road and cattle herding activities, affected habitat utilization throughout the year whereas other variables were important only during restricted periods. For instance, geo-physical variables were influential in the premating and cub-rearing seasons while vegetation variables were important in all seasons other than premating. Red pandas selected steeper slopes with high solar insolation in the premating season while they occupied elevated areas and preferred specific aspects in the cub-rearing season. Furthermore, the utilized areas had tall bamboo in the birthing and cub-rearing seasons while they also preferred diverse tree species and high shrub cover in the latter. Our study demonstrates the significance of season-specific management, suggests the importance of specific types of vegetation during biologically crucial periods, and emphasizes the necessity to minimize disturbances throughout the year.