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This review summarises recent developments in structural characterisation of CDKs and alternative non-ATP competitive ways to inhibit them.

Involving research users in setting priorities for research is essential to ensure the outcomes are patient-centred and\ud maximise its value and impact. The Musculoskeletal Disorders Research Advisory Group Versus Arthritis led a\ud research priority setting exercise across musculoskeletal disorders. The Child Health and Nutrition Research Initiative\ud (CHNRI) method of setting research priorities with a range of stakeholders was used, involving four stages and two\ud surveys, to: (1) gather research uncertainties, (2) consolidate these, (3) score uncertainties against importance and\ud impact, and (4) analyse scoring for prioritisation. 213 people responded to the first survey and 285 people to the\ud second, representing clinicians, researchers, and people with musculoskeletal disorders. Key priorities included\ud developing and testing new treatments, better treatment targeting, early diagnosis, prevention, and better\ud understanding and management of pain, with an emphasis on understanding underpinning mechanisms. We\ud present a call to action to researchers and funders to target these priorities.

High-throughput screening provides one of the most common ways of finding hit compounds. Lead-like libraries, in particular, provide hits with compatible functional groups and vectors for structural elaboration and physical properties suitable for optimization. Library synthesis approaches can lead to a lack of chemical diversity because they employ parallel derivatization of common building blocks using single reaction types. We address this problem through a "build-couple-transform" paradigm for the generation of lead-like libraries with scaffold diversity. Nineteen transformations of a 4-oxo-2-butenamide scaffold template were optimized, including 1,4-cyclizations, 3,4-cyclizations, reductions, and 1,4-additions. A pool-transformation approach efficiently explored the scope of these transformations for nine different building blocks and synthesized a170-member library with enhanced chemical space coverage and favorable drug-like properties. Screening revealed hits against CDK2. This work establishes the build-couple-transform concept for the synthesis of lead-like libraries and provides a differentiated approach to libraries with significantly enhanced scaffold diversity.

Thermal proteome profiling (TPP) provides a powerful approach to studying proteome-wide interactions of small therapeutic molecules and their target and off-target proteins, complementing phenotypic-based drug screens. Detecting differences in thermal stability due to target engagement requires high quantitative accuracy and consistent detection. Isobaric tandem mass tags (TMT) are used to multiplex samples and increase quantification precision in TPP analysis by data-dependent acquisition (DDA). However, advances in data-independent acquisition (DIA) can provide higher sensitivity and protein coverage with reduced costs and sample preparation steps. Herein, we explored the performance of different DIA-based label-free quantification (LFQ) approaches compared to TMT-DDA for thermal shift quantitation. Acute myeloid leukaemia (AML) cells were treated with losmapimod, a known inhibitor of MAPK14 (p38α). Label-free DIA approaches, and particularly the library-free mode in DIA-NN, were comparable or better than TMT-DDA in their ability to reproducibly detect target engagement of losmapimod with MAPK14 and one of its downstream targets, MAPKAPK3. Using DIA for thermal shift quantitation is a cost-effective alternative to labelled quantitation in the TPP pipeline.

More than 40% of individuals will develop osteoarthritis (OA) during their lifetime, yet there are currently no licensed disease-modifying treatments for this disabling condition. Common polymorphic variants in

Objectives Knee joint distraction (KJD) has been associated with clinical and structural improvement and SF marker changes. The current objective was to analyse radiographic changes after KJD using an automatic artificial intelligence-based measurement method and relate these to clinical outcome and SF markers. Methods Twenty knee osteoarthritis patients were treated with KJD in regular care. Radiographs and WOMAC were collected before and ∼1 year post-treatment. SF was aspirated before, during and after treatment; biomarker levels were assessed by immunoassay. Radiographs were analysed to obtain compartmental minimum and standardized joint space width (JSW), Kellgren–Lawrence (KL) grades, compartmental joint space narrowing (JSN) scores, and osteophytosis and sclerosis scores. Results were analysed for the most affected compartment (MAC) and least affected compartment. Radiographic changes were analysed using the Wilcoxon signed rank test for categorical and paired t-test for continuous variables. Linear regression was used to calculate associations between changes in JSW, WOMAC pain and SF markers. Results Sixteen patients could be evaluated. JSW, KL and JSN improved in around half of the patients, significant only for MAC JSW (P Conclusion Automatic radiographic measurements show improved joint structure in most patients after KJD in regular care. MAC JSW increased significantly and was associated with SF biomarker level changes and even with improvements in pain as experienced by these patients.

Abstract. We conceptualized and developed a measure of right-wing protective popular nationalism (RWPPN) – a specific form of popular nationalism where people seek to protect the national culture from outgroup influences. RWPPN is derived from a sociological analysis of right-wing popular nationalism in Australia and is theoretically related to several key psychological constructs, including right-wing authoritarianism (RWA), social dominance orientation (SDO), and symbolic threat. We conducted two surveys using nationally representative samples of Australian citizens. In study 1 ( n = 657), participants completed measures of RWPPN and related constructs. Exploratory and confirmatory factor analysis resulted in a 10-item scale. Construct validity was tested and confirmed across divergent, convergent, predictive, and concurrent validation domains. Additional convergent validation with RWA and SDO was tested in study 2 ( n = 316). Together, RWPPN was found to relate to expressions of national identity, prejudice, perceived outgroup threat, opposition to multiculturalism, and aggressive tendencies toward ethnic minorities. These effects remained significant when controlling for nationalism (measured as a concern for national superiority) and blind patriotism. In study 2, the effect on aggressive tendencies held when controlling for RWA and SDO and RWPPN mediated the relationship between RWA and aggressive tendencies. Reflecting the conservative nature of Australian popular nationalism, RWPPN correlated with right-wing political alignment. The research was conducted in Australia, but given the rise in right-wing populism internationally, RWPPN may be a phenomenon in other countries. Therefore, this paper offers a new construct and scale to investigate it in Australia and internationally.

This overview of progress made in preventing post-traumatic osteoarthritis (PTOA) was delivered in a workshop at the Orthopaedics Research Society Annual Conference in 2019. As joint trauma is a major risk factor for OA, defining the molecular changes within the joint at the time of injury may enable the targeting of biological processes to prevent later disease. Animal models have been used to test therapeutic targets to prevent PTOA. A review of drug treatments for PTOA in rodents and rabbits between 2016 and 2018 revealed 11 systemic interventions, 5 repeated intra-articular or topical interventions, and 5 short-term intra-articular interventions, which reduced total Osteoarthritis Research Society International scores by 30%-50%, 20%-70%, and 0%-40%, respectively. Standardized study design, reporting of effect size, and quality metrics, alongside a "whole joint" approach to assessing efficacy, would improve the translation of promising new drugs. A roadblock to translating preclinical discoveries has been the lack of guidelines on the design and conduct of human trials to prevent PTOA. An international workshop addressing this in 2016 considered inclusion criteria and study design, and advocated the use of experimental medicine studies to triage candidate treatments and the development of early biological and imaging biomarkers. Human trials for the prevention of PTOA have tested anakinra after anterior cruciate ligament rupture and dexamethasone after radiocarpal injury. PTOA offers a unique opportunity for defining early mechanisms of OA to target therapeutically. Progress in trial design and high-quality preclinical research, and allegiance with patients, regulatory bodies, and the pharmaceutical industry, will advance this field.

The prolific expansion of intergroup contact research has established that intergroup interactions are tightly linked to social integration. In this review, recent technological and statistical innovations with the potential to advance this body of research are presented. First, concerns over the validity of longitudinal models are discussed before innovative analytical techniques are introduced that explore change over time. Next, intensive repeated measure designs, such as experience sampling approaches, are introduced as opportunities to investigate the day‐to‐day lives of individuals. Virtual reality technology is then presented as another means to examine naturalistic contact experiences in the laboratory, offering researchers an unrivaled capacity to induce uncommon contact experiences. Finally, we propose that additional sources of contextual data, such as competing media messages, could extend these models in innovative ways by accounting for the time and place surrounding intergroup contact. Similarly, longitudinal social network analysis can provide additional contextual information by considering the broader network environment in which contact occurs. We describe these innovations with the intention of spurring future research that will advance our understanding of how intergroup contact can be used to improve our societies. Thus, we conclude with a discussion on how to bridge divides between researchers and practitioners.

Deroceras reticulatum also known as the Grey Field Slug is a serious agricultural and horticultural pest. Integrated pest management of D. reticulatum and other pest molluscs includes the use of ch...

COVID-19 has affected many healthcare workers (HCWs) globally. We performed state-wide SARS-CoV-2 genomic epidemiological investigations to identify HCW transmission dynamics and provide recommendations to optimise healthcare system preparedness for future outbreaks.Genome sequencing was attempted on all COVID-19 cases in Victoria, Australia. We combined genomic and epidemiologic data to investigate the source of HCW infections across multiple healthcare facilities (HCFs) in the state. Phylogenetic analysis and fine-scale hierarchical clustering were performed for the entire dataset including community and healthcare cases. Facilities provided standardised epidemiological data and putative transmission links.Between March-October 2020, approximately 1,240 HCW COVID-19 infection cases were identified; 765 are included here, requested for hospital investigations. Genomic sequencing was successful for 612 (80%) cases. Thirty-six investigations were undertaken across 12 HCFs. Genomic analysis revealed that multiple introductions of COVID-19 into facilities (31/36) were more common than single introductions (5/36). Major contributors to HCW acquisitions included mobility of staff and patients between wards and facilities, and characteristics and behaviours of patients that generated numerous secondary infections. Key limitations at the HCF level were identified.Genomic epidemiological analyses enhanced understanding of HCW infections, revealing unsuspected clusters and transmission networks. Combined analysis of all HCWs and patients in a HCF should be conducted, supported by high rates of sequencing coverage for all cases in the population. Established systems for integrated genomic epidemiological investigations in healthcare settings will improve HCW safety in future pandemics.The Victorian Government, the National Health and Medical Research Council Australia, and the Medical Research Future Fund.

Canadian and international research has shown that the COVID-19 pandemic has led to changes in health behaviours, including physical activity.The Canadian Community Health Survey asked Canadian youth (12 to 17 years) and adults (18 years and older) to report the amount of time they spent in the past seven days engaged in physical activity across the following domains: recreation, transportation, household or occupation, and school (youth only). The present analysis compares the physical activity from two cross-sectional samples collected during the fall of 2018 (n=13,482) and the fall of 2020 (n=27,234).Youth reported accumulating, on average, two hours less physical activity per week in the fall of 2020 compared with the fall of 2018 (-129 minutes per week). The percentage of youth meeting the Canadian physical activity recommendation for children and youth dropped from 50.8% in the fall of 2018 to 37.2% in the fall of 2020. Physical activity decreased more among youth living in urban (-135 minutes per week) compared with rural (-86 minutes per week) areas. Physical activity decreased more among youth from Ontario (-168 minutes per week), Quebec (-121 minutes per week) and the Prairies (-106 minutes per week) compared with youth from the Atlantic provinces (-38 minutes per week) and British Columbia (-75 minutes per week). There was no change in the percentage of adults aged 18 and older meeting the Canadian physical activity recommendation between the fall of 2018 (52.7%) and the fall of 2020 (53.3%). Weekly physical activity was stable between fall 2018 and fall 2020 among 18 to 49 year olds, while significant increases were observed among adults aged 50 to 64 years (+41 minutes per week), 65 to 79 years (+55 minutes per week) and 80+ years (+20 minutes per week). Increases in physical activity among adults were statistically significant only among non-immigrant, non-Indigenous, those not designated as a visible minority, those living in urban areas and those with a postsecondary degree.The COVID-19 pandemic had a detrimental impact on the physical activity of youth but not adults. The findings of this study add to a growing body of evidence that shows the considerable impact the pandemic has had on many aspects of Canadian life, including physical activity.

Autologous chimeric antigen receptor (CAR) T therapies utilize patient cells and can be limited by cell quality, and the high manufacturing burden of viral vectors. As such, there is a need for allogeneic, “off-the-shelf” CAR T cells to make these transformative treatments widely available. However, allogeneic therapies require multiple genetic engineering steps to express CAR and to delete proteins responsible for graft-versus-host disease. Messenger RNA (mRNA) is a promising approach for expression of therapeutic proteins and gene editing nucleases. In this work, we demonstrate a new method for multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles (LNPs). LNPs encapsulating Spy-Cas9 mRNA, TCR and CD52 guide RNA (sgRNA), and CAR mRNA were produced using microfluidics. The CAR construct contained an anti-CD19 scFv binding domain and CD3ζ/4-1BB co-stimulatory domains. Microgram quantities of RNA LNPs were produced to optimize LNP packaging, cargo ratios, and sgRNA combinations. Lead candidates were scaled to milligrams. Purified human primary T cells were cultured, activated, and expanded in serum-free media in plates, flasks and bioreactors. CAR+, TCR− or CD52− cells were generated by addition of the corresponding LNP to activated cells. Cytotoxic killing was determined by co-culture assays with leukemia cells. Gene knockout, CAR expression, viability and cell killing were measured using flow-cytometry. CD19 CAR was selected as a relevant protein for expression, with TCR and CD52 proteins as gene knockout targets. Single-step addition of CAR LNPs to T cells resulted in transfection efficiencies of 95.0 ± 2.1% and high protein expression. Upon TCR or CD52 LNP addition to T cells, the onset of gene editing was within 48 hours, reaching single target knockout efficiencies of 92.3 ± 3.0% (TCR−), and double knockouts (TCR−/CD52−) of 74.5 ± 6.1%. Similar results were obtained when comparing different LNP batch sizes (microgram to milligram RNA) and cell culture vessels (125,000 to 45 million cells), demonstrating scalability of both the LNP production and cell treatment. Cell viabilities above 90% were maintained at all steps and for all RNA LNPs. Finally, as proof-of-concept for multi-step engineering, sequential addition of TCR LNPs and CAR LNPs resulted in simultaneous CAR expression and TCR gene knockout. These “off-the-shelf” gene-edited CAR T cells were functionally equivalent to non-edited cells in a B cell killing assay, efficiently clearing over 80% of leukemia target cells at a 1:1 ratio. Our findings demonstrate the advantages of LNPs for RNA delivery to T cells. The simple and gentle nature of LNP cell treatment allows for multiple genetic engineering steps for simultaneous expression and deletion of proteins. Furthermore, LNPs can be easily manufactured using microfluidics, enabling small-scale screening of RNA libraries and rapid scale-up of lead candidates for clinical translation. Citation Format: Samuel Clarke, R Geczy, A Balgi, S Park, R Zhao, M Swaminathan, R Tieu, N Hoang, C Webb, E Watt, M Wong, M Fujisawa, N Jain, Angela Zhang, Anitha Thomas. Multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1785.

Estimating key aspects of transmission is crucial in infectious disease control. Serial intervals – the time between symptom onset in an infector and infectee – are fundamental, and help to define rates of transmission, estimates of reproductive numbers, and vaccination levels needed to prevent transmission. However, estimating the serial interval requires knowledge of individuals’ contacts and exposures (who infected whom), which is typically obtained through resource-intensive contact tracing efforts. We develop an alternate framework that uses virus sequences to inform who infected whom and thereby estimate serial intervals. The advantages are many-fold: virus sequences are often routinely collected to support epidemiological investigations and to monitor viral evolution. The genomic approach offers high resolution and cluster-specific estimates of the serial interval that are comparable with those obtained from contact tracing data. Our approach does not require contact tracing data, and can be used in large populations and over a range of time periods. We apply our techniques to SARS-CoV-2 sequence data from the first two waves of COVID-19 in Victoria, Australia. We find that serial interval estimates vary between clusters, supporting the need to monitor this key parameter and use updated estimates in onward applications. Compared to an early published serial interval estimate, using cluster-specific serial intervals can cause estimates of the effective reproduction number Rt to vary by a factor of up to 2–3. We also find that serial intervals estimated in settings such as schools and meat processing/packing plants tend to be shorter than those estimated in healthcare facilities.

Osteoarthritis (OA) is the most common form of joint disease, and its impact is set to grow as the prevalence of obesity rises and the elderly population increases. Many clinicians regard OA as simply a disease of ‘wear and tear’, and by implication one in which disease modification is not possible. Such prejudices previously led to significant academic apathy in this disease area, reflected not only in our poor understanding of disease pathogenesis, but also in the failure to classify the disease with greater precision and develop sensitive tools for diagnosis and prognostic assessment. The identification of key degradative enzymes in cartilage, the appreciation that damaged articular cartilage has repair capabilities and the recognition that ‘good’ and ‘bad’ mechanical stress triggers different molecular pathways have greatly changed the outlook in recent years. Evidence-based management of the condition is outlined in international guidelines: education, weight control/loss and exercise (general, joint specific) are core interventions. Analgesia and non-pharmacological and surgical approaches that favourably affect joint biomechanics are used for treating painful OA unresponsive to core interventions. The disease remains the most common reason for joint replacement surgery. There are no licensed disease-modifying OA drugs but recent clinical trials suggest that these may be within reach.

Knee joint distraction (KJD) treatment has shown cartilage repair and clinical improvement in patients with osteoarthritis, as has high tibial osteotomy (HTO). Following KJD, TGFβ-1 and IL-6 were increased in synovial fluid (SF), factors related to cartilage regeneration, but also to osteophyte formation. As such, osteophyte formation after both joint-preserving treatments was studied. Radiographic osteophyte size was measured before, one year, and two years after treatment. Changes were compared with natural progression in patients from the CHECK cohort before undergoing total knee arthroplasty. An additional KJD cohort underwent SF aspiration, and one-year Altman osteophyte score changes were compared to SF-marker changes during treatment. After two years, both KJD (n = 58) and HTO (n = 38) patients showed an increase in osteophyte size (+6.2 mm2 and +7.0 mm2 resp., both p &lt, 0.004), with no significant differences between treatments (p = 0.592). Untreated CHECK patients (n = 44) did not show significant two-year changes (+2.1 mm2, p = 0.207) and showed significant differences with KJD and HTO (both p &lt, 0.044). In SF aspiration patients (n = 17), there were significant differences in TGFβ-1 changes (p = 0.044), but not IL-6 (p = 0.898), between patients with a decrease, no change, or increase in osteophyte Altman score. Since KJD and HTO showed joint space widening and clinical improvement accompanied by osteophyte formation, increased osteophytosis after joint-preserving treatments may be a bystander effect of cartilage repair activity related to intra-articular factors like TGFβ-1 and raises questions regarding osteophyte formation as solely characteristic of the joint degenerative process.

Involving research users in setting priorities for musculoskeletal research is essential to raise awareness of the unmet needs for MSK research, to ensure research outcomes are patient-centred and relevant, have a high likelihood of resulting in patient benefit, reduce research waste and increase research value and impact. In 2018, Versus Arthritis convened an MSK Disorders Research Advisory Group (RAG) which included people with arthritis, health care professionals and researchers in MSK, in order to identify and prioritise research areas with a long-term aim of improving quality and impact of MSK research. On further review, there were few previous prioritisation approaches in this area looking across discovery science to more clinical research, at important research questions which might be common to a range of disorders or approaches incorporating input at all stages of the process by a range of stakeholders including people with arthritis. The group identified that more work to define research priorities in these areas was justified and designed a research priority setting process for MSK disorders. This manuscript documents the methodology that was developed by the group for this process.MethodsFollowing a review, the Child Health and Nutrition Research Initiative (CHNRI) method for research prioritisation was selected as best aligning with the needs of this process. The group agreed on adaptations to the CHNRI approach, context, purpose and remit of the exercise and identified through consensus four priority research Domains: Mechanisms of disease; Diagnosis (including early diagnosis) and measuring the impact of these disorders; Living well with MSK disorders and Successful Translation. From all published CHNRI scoring criteria for generated research avenues or themes of research, the group identified six which were most relevant to this process. To ensure accessibility of the survey and scoring, these were refined to three: Equity (considered cross cutting, not scored but considered throughout the process), Importance (Will research in this area have potential to lead to important new knowledge) and Impact (Might research in this area make a difference). Importance and Impact were to be scored on a scale of 1-10 for each research avenue with equal weighting of these two criteria in the subsequent generation of a total score.Data collectionFollowing ethical approval, an electronic first survey asking for important research uncertainties in the four research domains and any other areas will be distributed to all stakeholders (people with arthritis, researchers in all stages of MSK disorders research, healthcare professionals, industry e.g. pharmaceutical and medical technology companies, research funders, healthcare providers, government policy makers and charities). The next step is to consolidate all the gathered research uncertainties from the first survey into finalised research domains and avenues. Uncertainties will be summarised using deductive thematic analysis and organised into possible themes which will then be considered and refined by each of four appointed subgroups within the RAG. Following group and lay review and refinement of the wording including tests of readability, the second survey including this full list of research avenues will be submitted for ethical approval. The second survey will be completed by the same range of stakeholders as the first survey, both those who previously completed and new respondents. Respondents will be invited to rate each research avenue using the two scoring criteria, with the avenues presented in a random sequence to avoid bias.Analysis PlanAll available data will be analysed, from all respondents completing the survey in full and all partial respondents. For each research avenue, a mean criterion score will be calculated for each of the two criteria from all available survey responses (considering the number of respondents in each case), and then the two mean criterion scores will be summed to create a total score. Response rates and missing data for scoring of avenues will be reported. The primary prioritisation output of this exercise will be to produce a single ranked list of these total scores of research avenues, from highest to lowest. The most highly ranked avenues will be highlighted, for example the top five to top ten overall and from each research domain, with the exact number and nature of this depending on the distribution of the data. Respondent characteristics will be summarised including self-identified stakeholder group, age group, gender and ethnic background, to describe the diversity and representation within the survey respondents as far as possible.Dissemination planFindings will be communicated in a number of formats, both written and spoken, to ensure accessibility to all stakeholders, and will also be used by the charity in internal strategy development. Dissemination will include the submission of a manuscript to a peer-reviewed journal.

Over 40% of individuals will develop osteoarthritis (OA) during their lifetime, yet there are currently no licensed disease modifying treatments for this disabling condition. Common polymorphic variants in ALDH1A2, that encodes the key enzyme in the synthesis of all-trans retinoic acid (atRA), have been associated with severe hand OA. In this study, we sought to elucidate the biological significance of this association. We first confirmed that ALDH1A2 risk variants were associated with hand OA in UK Biobank. Articular cartilage was acquired from 33 consenting individuals with hand OA at the time of routine hand OA surgery. They were stratified by genotype and RNA sequencing performed. A reciprocal relationship between ALDH1A2 mRNA and inflammatory genes was observed. Articular cartilage injury up-regulates similar inflammatory genes by a process that we have previously termed mechanoflammation, and which we believe is a primary driver of OA. Cartilage injury was also associated with a concomitant drop in atRA-dependent genes, indicative of cellular atRA levels, and both responses to injury were reversed using talarozole, a retinoic acid metabolism blocking agent (RAMBA). Suppression of mechanoflammation by talarozole was mediated by a peroxisome proliferator activated receptor (PPAR)-γ dependent mechanism. Talarozole, delivered by minipump, was able to suppress mechano-inflammatory genes in articular cartilage in vivo 6h after mouse knee joint destabilization, and reduced cartilage degradation and osteophyte formation after 4 weeks. These data show that boosting atRA suppresses mechanoflammation in the articular cartilage in vitro and in vivo, and identifies RAMBAs as potential disease modifying drugs in OA.One Sentence SummaryAnalysis of hand OA cartilage stratified by ALDH1A2 polymorphic variants reveals a targetable, anti-inflammatory role for retinoic acid in OA.

BackgroundCOVID-19 has resulted in many infections in healthcare workers (HCWs) globally. We performed state-wide SARS-CoV-2 genomic epidemiological investigations to identify HCW transmission dynamics and provide recommendations to optimise healthcare system preparedness for future outbreaks.MethodsGenome sequencing was attempted on all COVID-19 cases in Victoria, Australia. We combined genomic and epidemiologic data to investigate the source of HCW infections across multiple healthcare facilities (HCFs) in the state. Phylogenetic analysis and fine-scale hierarchical clustering were performed for the entire Victorian dataset including community and healthcare cases. Facilities provided standardised epidemiological data and putative transmission links.FindingsBetween March and October 2020, approximately 1,240 HCW COVID-19 infection cases were identified; 765 are included here. Genomic sequencing was successful for 612 (80%) cases. Thirty-six investigations were undertaken across 12 HCFs. Genomic analysis revealed that multiple introductions of COVID-19 into facilities (31/36) were more common than single introductions (5/36). Major contributors to HCW acquisitions included mobility of staff and patients between wards and facilities, and characteristics and behaviours of individual patients including super-spreading events. Key limitations at the HCF level were identified.InterpretationGenomic epidemiological analyses enhanced understanding of HCW infections, revealing unsuspected clusters and transmission networks. Combined analysis of all HCWs and patients in a HCF should be conducted, supported by high rates of sequencing coverage for all cases in the population. Established systems for integrated genomic epidemiological investigations in healthcare settings will improve HCW safety in future pandemics.FundingThe Victorian Government, the National Health and Medical Research Council Australia, and the Medical Research Future Fund.

Background Joint injury is a major risk factor for osteoarthritis and provides an opportunity to prospectively examine early processes associated with osteoarthritis. We investigated whether predefined baseline demographic and clinical factors, and protein analytes in knee synovial fluid and in plasma or serum, were associated with clinically relevant outcomes at 2 years after knee injury. Methods This longitudinal cohort study recruited individuals aged 16–50 years between Nov 1, 2010, and Nov 28, 2014, across six hospitals and clinics in London, UK. Participants were recruited within 8 weeks of having a clinically significant acute knee injury (effusion and structural injury on MRI), which was typically treated surgically. We measured several predefined clinical variables at baseline (eg, time from injury to sampling, extent and type of joint injury, synovial fluid blood staining, presence of effusion, self-reported sex, age, and BMI), and measured 12 synovial fluid and four plasma or serum biomarkers by immunoassay at baseline and 3 months. The primary outcome was Knee Injury and Osteoarthritis Outcome Score (KOOS4) at 2 years, adjusted for baseline score, assessed in all patients. Linear and logistic regression models adjusting for predefined covariates were used to assess associations between baseline variables and 2-year KOOS4. This study is registered with ClinicalTrials.gov, number NCT02667756. Findings We enrolled 150 patients at a median of 17 days (range 1–59, IQR 9–26) after knee injury. 123 (82%) were male, with a median age of 25 years (range 16–50, IQR 21–30). 98 (65%) of 150 participants completed a KOOS4 at 2 (or 3) years after enrolment (50 participants were lost to follow-up and two were withdrawn due to adverse events unrelated to study participation); 77 (51%) participants had all necessary variables available and were included in the core variable adjusted analysis. In the 2-year dataset mean KOOS4 improved from 38 (SD 18) at baseline to 79 (18) at 2 years. Baseline KOOS4, medium-to-large knee effusion, and moderate-to-severe synovial blood staining and their interaction significantly predicted 2-year KOOS4 (n=77; coefficient −20·5, 95% CI −34·8 to −6·18; p=0·0060). The only predefined biomarkers that showed independent associations with 2-year KOOS4 were synovial fluid MCP-1 (n=77; −0·015, 0·027 to −0·004 per change in 1 pg/mL units; p=0·011) and IL-6 (n=77; −0·0005, −0·0009 to −0·0001 per change in 1 pg/mL units; p=0·017). These biomarkers, combined with the interaction of effusion and blood staining, accounted for 39% of outcome variability. Two adverse events occurred that were linked to study participation, both at the time of blood sampling (one presyncopal episode, one tenderness and pain at the site of venepuncture). Interpretation The combination of effusion and haemarthrosis was significantly associated with symptomatic outcomes after acute knee injury. The synovial fluid molecular protein response to acute knee injury (best represented by MCP-1 and IL-6) was independently associated with symptomatic outcomes but not with structural outcomes, with the biomarkers overall playing a minor role relative to clinical predictors. The relationship between symptoms and structure after acute knee injury and their apparent dissociation early in this process need to be better understood to make clinical progress. Funding Versus Arthritis, Kennedy Trust for Rheumatology Research, and NIHR Oxford Biomedical Research Centre.

Background Hand osteoarthritis (OA) is a common condition, causing pain, stiffness and reduced quality of life. Incidence is higher amongst women, particularly around the age of the menopause. Whilst the relationship between sex hormones and OA has been studied in vitro, in epidemiological studies and in clinical trials of hormone replacement therapy (HRT), this study is the first to investigate the effect of estrogen-containing therapy on hand pain in post-menopausal women with symptomatic hand OA in a randomised study design. Methods This is a feasibility study of a double-blinded placebo-controlled intervention with 1:1 randomisation to either a combination of conjugated estrogens 0.45 mg and bazedoxifene acetate 20 mg (Duavive) or placebo. The target population is post-menopausal women with symptomatic hand OA, aiming to recruit 60–90 study participants. The primary objective is to assess the feasibility of a future fully powered randomised controlled trial (RCT). Participants will take the study medication for 24 weeks and be followed up for 28 weeks after randomisation. The primary outcomes used to determine feasibility are eligible participant identification rates and routes; recruitment, randomisation and retention rates of eligible participants; study medication compliance; and the likelihood of unintentional unblinding. Secondary outcomes include measures of hand pain, function, appearance and menopausal symptoms. An end of study questionnaire and focus groups will help to refine the final protocol for a full study. Discussion Identifying new treatments for symptomatic hand OA is a recognised research priority. The study will help us to understand whether there are sufficient interested and eligible individuals in this target population who would consider HRT for their hand symptoms. It will provide proof-of-concept RCT data on the effects of HRT on hand pain and other clinically relevant outcomes in this population. The study will gain valuable information on the feasibility of a full RCT and how best to run this. The findings will be published in a peer-reviewed journal and presented at a relevant conference. Trial registration ISRCTN12196200 registered on 15 January 2019.

While the majority of children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) display mild or no symptoms, rare individuals develop severe disease presenting with multisystem inflammatory syndrome (MIS-C). The reason for variable clinical manifestations is not understood. Here, we carried out TCR sequencing and conducted comparative analyses of TCR repertoires between children with severe (n=12) or mild (n=8) COVID-19. We compared these repertoires with unexposed individuals (samples collected pre-COVID-19 pandemic: n=8) and with the Adaptive Biotechnologies MIRA dataset, which includes over 135,000 high-confidence SARS-CoV-2-specific TCRs. We show that the repertoires of severely ill children are characterised by the expansion of TRBV11-2 chains with high junctional and CDR3 diversity. Moreover, the CDR3 sequences of TRBV11-2 clones shift away from SARS-CoV-2 specific T cell clones, resulting in distorted TCR repertoires. In conclusion, our study reports that CDR3-independent expansion of TRBV11-2+ cells, lacking SARS-CoV-2 specificity, defines severity of disease in children.

Purpose: Hand osteoarthritis (OA) is more common in women and previous studies have noted its incidence increases around the time of the menopause. More recently, there has been a report in a large primary care dataset of increased incidence of hand OA following cessation of menopausal hormonal therapy (MHT). We set out to describe the temporal relationship between menopause, use of MHT and the onset of hand symptoms in a population of women with hand OA in a secondary care (rheumatology) setting. Our objectives were: i) to explore if there was a temporal relationship between the onset of menopause and the onset of hand OA symptoms; ii) to describe if current or previous use of MHT was associated with the timing of onset of hand OA symptoms; iii) To examine if cessation of MHT was associated with onset of hand OA symptoms. Methods: This was a retrospective review of UK NHS medical records (UK IRAS ethics #282499). Sequential females aged 18 years and older referred to specialist hand OA clinic in London, UK 2007-2015 with a diagnosis of Hand OA by accepted clinical criteria were included; exclusions were other forms of arthritis or causes of hand pain. Predefined outcome measures were reported age of onset of hand symptoms, reported age of Final Menstrual Period (FMP); predefined variables were use of systemic estrogen-containing MHT (subgroups current, previous, never users) and menopausal status (premenopausal, post-menopausal [at least one year post FMP]; peri-menopausal period defined as FMP+/- 4 years). These variables, age and other demographics were from the usual healthcare records, with all predefined variables recorded by standardised proforma used routinely in this setting. Descriptive statistics and linear regression modelling (coefficient, 95% CI are given) were carried out in STATA IC. Results: 82/98 females were post-menopausal, with mean age at FMP of 50. In these post-menopausal women, median time from FMP to hand symptom onset was 3 years (range -25, 60 years). 48/82 (59%) of these women developed their hand symptoms within the defined peri-menopausal period. In women who had discontinued MHT, the median time from cessation of therapy to onset of hand symptoms was 6 months. Past users of MHT were older at onset of reported hand symptoms than women who had not taken MHT (coeff.4.7 (0.92, 8.39); P=0.015). This association persisted when adjusted for menopausal status. Conclusions: This study of real-world, patient-level data in women in a hospital care setting adds to the circumstantial evidence which associates the menopause with onset of OA symptoms; in this population, a significant subgroup of women are seen to present around the time of their menopause with hand OA symptoms. The use of MHT and its cessation appeared to be associated with the age of onset of hand OA symptoms in this particular population. There of limitations of this type of study, including risk of recall or referral bias, or other uncontrolled bias; also that the type and duration of MHT could not be taken into account. It is important that these findings are re-tested in different settings. It cannot be known from this type of study whether the effects of menopause are mediated by sex hormone deficiency directly or by other factors; also whether menopause is causative, is a disease modifier or a symptom modifier in these women. OA is a female-preponderant disease: the sexual dimorphism particularly observed in hand OA and the clues that the influence of menopause may give us on the underlying pathogenesis of OA deserve more attention.

PURPOSE OF REVIEW: Current thinking in the study of posttraumatic osteoarthritis (PTOA) is overviewed: the osteoarthritis which follows acute joint injury. The review particularly highlights important publications in the last 18 months, also reflecting on key older literature, in terms of what have we have we learned and have yet to learn from PTOA, which can advance the osteoarthritis field as a whole. RECENT FINDINGS: PTOA is a mechanically driven disease, giving insight into mechanical drivers for osteoarthritis. A mechanosensitive molecular tissue injury response (which includes activation of pain, degradative and also repair pathways) is triggered by acute joint injury and seen in osteoarthritis. Imaging features of PTOA are highly similar to osteoarthritis, arguing against it being a different phenotype. The inflammatory pathways activated by injury contribute to early joint symptoms. However, later structural changes appear to be dissociated from traditional measures of synovial inflammation. SUMMARY: PTOA remains an important niche in which to understand processes underlying osteoarthritis and seek interventional targets. Whether PTOA has true molecular or clinical differences to osteoarthritis as a whole remains to be understood. This knowledge is important for a field where animal modelling of the disease relies heavily on the link between injury and osteoarthritis.

The bone marrow (BM) vascular niche microenvironments harbor stem and progenitor cells of various lineages. Bone angiogenesis is distinct and involves tissue-specific signals. The nurturing vascular niches in the BM are complex and heterogenous consisting of distinct vascular and perivascular cell types that provide crucial signals for the maintenance of stem and progenitor cells. Growing evidence suggests that the BM niche is highly sensitive to stress. Aging, inflammation and other stress factors induce changes in BM niche cells and their crosstalk with tissue cells leading to perturbed hematopoiesis, bone angiogenesis and bone formation. Defining vascular niche remodeling under stress conditions will improve our understanding of the BM vascular niche and its role in homeostasis and disease. Therefore, this review provides an overview of the current understanding of the BM vascular niches for hematopoietic stem cells and their malfunction during aging, bone loss diseases, arthritis and metastasis.