A unifying model for extrachromosomal circular DNA load in eukaryotic cells.

Extrachromosomal circular DNA (eccDNA) with exons and whole genes are common features of eukaryotic cells. Work from especially tumours and the yeast Saccharomyces cerevisiae has revealed that eccDNA can provide large selective advantages and disadvantages. Besides the phenotypic effect due to expression of an eccDNA fragment, eccDNA is different from other mutations in that it is released from 1:1 segregation during cell division. This means that eccDNA can quickly change copy number, pickup secondary mutations and reintegrate into a chromosome to establish substantial genetic variation that could not have evolved via canonical mechanisms. We propose a unifying 5-factor model for conceptualizing the eccDNA load of a eukaryotic cell, emphasizing formation, replication, segregation, selection and elimination. We suggest that the magnitude of these sequential events and their interactions determine the copy number of eccDNA in mitotically dividing cells. We believe that our model will provide a coherent framework for eccDNA research, to understand its biology and the factors that can be manipulated to modulate eccDNA load in eukaryotic cells.

Hyperglycemic Memory of Innate Immune Cells Promotes In Vitro Proinflammatory Responses of Human Monocytes and Murine Macrophages.

It has been well established that the presence of diabetes is accompanied by a chronic inflammatory state promoting various diabetes-associated complications. One potential driver of this enhanced inflammatory state in patients with diabetes is hyperglycemia. Even after blood glucose control is achieved, diabetes-associated complications persist, suggesting the presence of a "hyperglycemic memory." Innate immune cells, critically involved in various complications associated with diabetes, can build nonspecific, immunological memory (trained immunity) via epigenetic regulation. We examine the potential involvement of hyperglycemia-induced trained immunity in promoting inflammation. Our results show that hyperglycemia induces a trained phenotype in vivo in mice and in vitro in human monocytes, representative by an increased TNF-α secretion after ex vivo stimulation with LPS. These effects were largely mediated by epigenetic changes controlled by the mixed lineage leukemia (MLL) family because treatment with the MLL inhibitor menin-MLL during the process of trained immunity acquisition repressed the proinflammatory phenotype. Collectively, our results identify a novel link between hyperglycemia and inflammation in innate immune cells that might explain the increased proinflammatory state during diabetes potentially contributing to the development of various diabetes-associated complications.

Catecholamines Induce Trained Immunity in Monocytes In Vitro and In Vivo.

RATIONALE: Exposure to high catecholamine levels is associated with inflammatory changes of myeloid cells and atherosclerosis, but the underlying mechanisms are only partly understood. OBJECTIVE: To investigate whether the proinflammatory effects of noradrenaline and adrenaline can, in part, be explained by the induction of an immunologic memory in innate immune cells, termed trained immunity. METHODS AND RESULTS: In vitro, we exposed human primary monocytes to (nor)adrenaline for 24 hours, after which cells were rested and differentiated to macrophages over 5 days. After restimulation with lipopolysaccharide on day 6, (nor)adrenaline-exposed cells showed increased TNF-α (tumor necrosis factor-α) production. This coincided with an increase in glycolysis and oxidative phosphorylation measured with Seahorse technology on day 6 before restimulation. Inhibition of the ß-adrenoreceptor-cAMP signaling pathway prevented the induction of training. In vivo, we studied the functional, transcriptional, and epigenetic impact of peak-wise exposure to high catecholamine levels on monocytes isolated from pheochromocytoma/paraganglioma (PHEO) patients. In PHEO patients (n=10), the peripheral blood cell composition showed a myeloid bias and an increase of the inflammatory CD14++CD16+ (cluster of differentiation) intermediate monocyte subset compared with controls with essential hypertension (n=14). Ex vivo production of proinflammatory cytokines was higher in PHEO patients. These inflammatory changes persisted for 4 weeks after surgical removal of PHEO. Transcriptome analysis of circulating monocytes at baseline showed various differentially expressed genes in inflammatory pathways in PHEO patients; epigenetic profiling of the promoters of these genes suggests enrichment of the transcriptionally permissive chromatin mark H3K4me3 (trimethylation of lysine 4 on histone H3), indicative of in vivo training. CONCLUSIONS: Catecholamines induce long-lasting proinflammatory changes in monocytes in vitro and in vivo, indicating trained immunity. Our data contribute to the understanding of pathways driving inflammatory changes in conditions characterized by high catecholamine levels and propose that trained immunity underlies the increased cardiovascular event rate in PHEO patients.

The role of sirtuin 1 on the induction of trained immunity.

Sirtuin 1 (SIRT1) has been described to modify immune responses by modulation of gene transcription. As transcriptional reprogramming is the molecular substrate of trained immunity, a de facto innate immune memory, we investigated the role of SIRT1 in the induction of trained immunity. We identified various SIRT1 genetic single nucleotide polymorphisms affecting innate and adaptive cytokine production of human peripheral blood mononuclear cells (PBMCs) in response to various stimuli on the one hand, and in vitro induction of trained immunity on the other hand. Furthermore, inhibition of SIRT1 upregulated pro-inflammatory innate cytokine production upon stimulation of PBMCs. However, inhibition of SIRT1 in vitro had no effect on cytokine responses upon induction of trained immunity, while activation of SIRT1 mildly modified trained immunity responses. In conclusion, SIRT1 modifies innate cytokine production by PBMCs in response to various microbes, but has only a secondary role for BCG and ß-glucan-induced trained immunity responses.

Cost-effectiveness of out-of-hospital continuous positive airway pressure for acute respiratory failure: decision analytic modelling using data from a feasibility trial.

BACKGROUND: Standard prehospital management for Acute respiratory failure (ARF) involves controlled oxygen therapy. Continuous positive airway pressure (CPAP) is a potentially beneficial alternative treatment, however, it is uncertain whether this could improve outcomes and provide value for money. This study aimed to evaluate the cost-effectiveness of prehospital CPAP in ARF. METHODS: A cost-utility economic evaluation was performed using a probabilistic decision tree model synthesising available evidence. The model consisted of a hypothetical cohort of patients in a representative ambulance service with undifferentiated ARF, receiving standard oxygen therapy or prehospital CPAP. Costs and quality adjusted life years (QALYs) were estimated using methods recommended by NICE. RESULTS: In the base case analysis, using CPAP effectiveness estimates form the ACUTE trial, the mean expected costs of standard care and prehospital CPAP were £15,201 and £14,850 respectively and the corresponding mean expected QALYs were 1.190 and 1.128, respectively. The mean ICER estimated as standard oxygen therapy compared to prehospital CPAP was £5685 per QALY which indicated that standard oxygen therapy strategy was likely to be cost-effective at a threshold of £20,000 per QALY (67% probability). The scenario analysis, using effectiveness estimates from an updated meta-analysis, suggested that prehospital CPAP was more effective (mean incremental QALYs of 0.157), but also more expensive (mean incremental costs of £1522), than standard care. The mean ICER, estimated as prehospital CPAP compared to standard care, was £9712 per QALY. At the £20,000 per QALY prehospital CPAP was highly likely to be the most cost-effective strategy (94%). CONCLUSIONS: Cost-effectiveness of prehospital CPAP depends upon the estimate of effectiveness. When based on a small pragmatic feasibility trial, standard oxygen therapy is cost-effective. When based on meta-analysis of heterogeneous trials, CPAP is cost-effective. Value of information analyses support commissioning of a large pragmatic effectiveness trial, providing feasibility and plausibility conditions are met.

Mechanisms of Action of a Web-Based Intervention With Health Professional Support to Increase Adherence to Nebulizer Treatments in Adults With Cystic Fibrosis: Qualitative Interview Study.

BACKGROUND: Adherence to nebulizer treatments in adults with cystic fibrosis (CF) is often low. A new complex intervention to help adults with CF increase their adherence to nebulizer treatments was tested in a pilot randomized controlled trial (RCT) in 2 UK CF centers. Patients used a nebulizer with electronic monitoring capabilities that transferred data automatically to a digital platform (CFHealthHub) to monitor adherence over time and to a tailored website to display graphs of adherence data and educational and problem-solving information about adherence. A trained interventionist helped patients identify ways to increase their adherence. OBJECTIVE: This study aims to explore the mechanisms of action underpinning the intervention. METHODS: A qualitative interview study was conducted concurrently with a pilot RCT. In total, 25 semistructured interviews were conducted with 3 interventionists at 2 time points, 14 patients in the intervention arm of the trial, and 5 members of the multidisciplinary teams offering wider care to patients. A framework approach was used for the analysis. RESULTS: The intervention was informed by a theoretical framework of behavior change. There was evidence of the expected behavior change mechanisms of action. There was also evidence of additional mechanisms of action associated with effective telehealth interventions for self-management support: relationships, visibility, and fit. Patients described how building a relationship with the interventionist through face-to-face visits with someone who cared about them and their progress helped them to consider ways of increasing adherence to medication. Rather than seeing the visibility of adherence data to clinicians as problematic, patients found this motivating, particularly if they received praise about progress made. The intervention was tailored to individuals, but there were challenges in how the intervention fitted into some patients' busy lives when delivered through a desktop computer. CONCLUSIONS: The mechanisms of action associated with effective telehealth interventions for self-management operated within this new intervention. The intervention was modified to strengthen mechanisms of action based on these findings, for example, delivery through an app accessed via mobile phones and then tested in an RCT in 19 UK CF centers. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number 13076797; http://www.isrctn.com/ISRCTN13076797.

Trained immunity and diabetic vascular disease.

Trained immunity is a recently described phenomenon whereby innate immune cells undergo functional reprogramming in response to microbial products, vaccines, or other stimuli, leading them to mount a sensitized nonspecific response to subsequent stimulation. While it is essential for the host response to pathogens, many diseases are the product of excessive or chronic inflammation. Atherosclerosis is a disease characterized by chronic low-grade inflammation of the arterial wall leading to plaque formation, where macrophages are the most abundant cell regulating plaque progression and stability. Recent studies have revealed a role for endogenous compounds related to atherosclerosis in the induction of trained immunity, which can enhance the expression of genes implicated in atherosclerosis and associated cardiovascular disease. Accelerated atherosclerosis remains the principal cause of morbidity and premature mortality in patients with diabetes, and the burden of vascular complications is greatly enhanced by prior periods of inadequate control of blood glucose. Recent findings suggest that long-term changes in bone marrow myeloid progenitors, similar to those induced by microbial products or high cholesterol diets in mice, may help to explain the chronic inflammatory state driving atherosclerosis and cardiovascular risk that exists for patients with diabetes despite improved metabolic control. From an immunometabolic perspective, we speculate that changes supporting the trained macrophage phenotype, such as up-regulation of glycolysis, indicate that a high glucose environment could enhance the pro-inflammatory consequences of trained immunity thereby contributing to the accelerated progression of atherosclerosis in patients with diabetes.

Epigenetics in diabetic nephropathy, immunity and metabolism.

When it comes to the epigenome, there is a fine line between clarity and confusion-walk that line and you will discover another fascinating level of transcription control. With the genetic code representing the cornerstone of rules for information that is encoded to proteins somewhere above the genome level there is a set of rules by which chemical information is also read. These epigenetic modifications show a different side of the genetic code that is diverse and regulated, hence modifying genetic transcription transiently, ranging from short- to long-term alterations. While this complexity brings exquisite control it also poses a formidable challenge to efforts to decode mechanisms underlying complex disease. Recent technological and computational advances have improved unbiased acquisition of epigenomic patterns to improve our understanding of the complex chromatin landscape. Key to resolving distinct chromatin signatures of diabetic complications is the identification of the true physiological targets of regulatory proteins, such as reader proteins that recognise, writer proteins that deposit and eraser proteins that remove specific chemical moieties. But how might a diverse group of proteins regulate the diabetic landscape from an epigenomic perspective? Drawing from an ever-expanding compendium of experimental and clinical studies, this review details the current state-of-play and provides a perspective of chromatin-dependent mechanisms implicated in diabetic complications, with a special focus on diabetic nephropathy. We hypothesise a codified signature of the diabetic epigenome and provide examples of prime candidates for chemical modification. As for the pharmacological control of epigenetic marks, we explore future strategies to expedite and refine the search for clinically relevant discoveries. We also consider the challenges associated with therapeutic strategies targeting epigenetic pathways.

Epigenetic Changes in Diabetes and Cardiovascular Risk.

Cardiovascular complications remain the leading causes of morbidity and premature mortality in patients with diabetes mellitus. Studies in humans and preclinical models demonstrate lasting gene expression changes in the vasculopathies initiated by previous exposure to high glucose concentrations and the associated overproduction of reactive oxygen species. The molecular signatures of chromatin architectures that sensitize the genome to these and other cardiometabolic risk factors of the diabetic milieu are increasingly implicated in the biological memory underlying cardiovascular complications and now widely considered as promising therapeutic targets. Atherosclerosis is a complex heterocellular disease where the contributing cell types possess distinct epigenomes shaping diverse gene expression. Although the extent that pathological chromatin changes can be manipulated in human cardiovascular disease remains to be established, the clinical applicability of epigenetic interventions will be greatly advanced by a deeper understanding of the cell type-specific roles played by writers, erasers, and readers of chromatin modifications in the diabetic vasculature. This review details a current perspective of epigenetic mechanisms of macrovascular disease in diabetes mellitus and highlights recent key descriptions of chromatinized changes associated with persistent gene expression in endothelial, smooth muscle, and circulating immune cells relevant to atherosclerosis. Furthermore, we discuss the challenges associated with pharmacological targeting of epigenetic networks to correct abnormal or deregulated gene expression as a strategy to alleviate the clinical burden of diabetic cardiovascular disease.

Vascular histone deacetylation by pharmacological HDAC inhibition.

HDAC inhibitors can regulate gene expression by post-translational modification of histone as well as nonhistone proteins. Often studied at single loci, increased histone acetylation is the paradigmatic mechanism of action. However, little is known of the extent of genome-wide changes in cells stimulated by the hydroxamic acids, TSA and SAHA. In this article, we map vascular chromatin modifications including histone H3 acetylation of lysine 9 and 14 (H3K9/14ac) using chromatin immunoprecipitation (ChIP) coupled with massive parallel sequencing (ChIP-seq). Since acetylation-mediated gene expression is often associated with modification of other lysine residues, we also examined H3K4me3 and H3K9me3 as well as changes in CpG methylation (CpG-seq). RNA sequencing indicates the differential expression of ∼30% of genes, with almost equal numbers being up- and down-regulated. We observed broad deacetylation and gene expression changes conferred by TSA and SAHA mediated by the loss of EP300/CREBBP binding at multiple gene promoters. This study provides an important framework for HDAC inhibitor function in vascular biology and a comprehensive description of genome-wide deacetylation by pharmacological HDAC inhibition.

Epigenetics and metabolism.

The molecular signatures of epigenetic regulation and chromatin architectures are fundamental to genetically determined biological processes. Covalent and post-translational chemical modification of the chromatin template can sensitize the genome to changing environmental conditions to establish diverse functional states. Recent interest and research focus surrounds the direct connections between metabolism and chromatin dynamics, which now represents an important conceptual challenge to explain many aspects of metabolic dysfunction. Several components of the epigenetic machinery require intermediates of cellular metabolism for enzymatic function. Furthermore, changes to intracellular metabolism can alter the expression of specific histone methyltransferases and acetyltransferases conferring widespread variations in epigenetic modification patterns. Specific epigenetic influences of dietary glucose and lipid consumption, as well as undernutrition, are observed across numerous organs and pathways associated with metabolism. Studies have started to define the chromatin-dependent mechanisms underlying persistent and pathophysiological changes induced by altered metabolism. Importantly, numerous recent studies demonstrate that gene regulation underlying phenotypic determinants of adult metabolic health is influenced by maternal and early postnatal diet. These emerging concepts open new perspectives to combat the rising global epidemic of metabolic disorders.

Deep sequencing reveals novel Set7 networks.

BACKGROUND: Methyl-dependent regulation of transcription has expanded from a traditional focus on histones to encompass transcription factor modulation. While the Set7 lysine methyltransferase is associated with pro-inflammatory gene expression in vascular endothelial cells, genome-wide regulatory roles remain to be investigated. From initial characterization of Set7 as specific for methyl-lysine 4 of H3 histones (H3K4m1), biochemical activity toward non-histone substrates has revealed additional mechanisms of gene regulation. RESULTS: mRNA-Seq revealed transcriptional deregulation of over 8,000 genes in an endothelial model of Set7 knockdown. Gene ontology identified up-regulated pathways involved in developmental processes and extracellular matrix remodeling, whereas pathways regulating the inflammatory response as well as nitric oxide signaling were down-regulated. Chromatin maps derived from ChIP-Seq profiling of H3K4m1 identified several hundred loci with loss of H3K4m1 at gene regulatory elements associated with an unexpectedly subtle effect on gene expression. Transcription factor network analysis implicated six previously described Set7 substrates in mRNA-Seq changes, and we predict that Set7 post-translationally regulates other transcription factors associated with vascular endothelial gene expression through the presence of Set7 amino acid methylation motifs. CONCLUSION: We describe a role for Set7 in regulating developmental pathways and response to stimuli (inflammation/immune response) in human endothelial cells of vascular origin. Set7-dependent gene expression changes that occurred independent of H3K4m1 may involve transcription factor lysine methylation events. The method of mapping measured transcriptional changes to transcription factors to identify putative substrates with strong associations to functional changes is applicable to substrate prediction for other broad-substrate histone modifiers.

Major Trauma Triage Tool Study (MATTS) expert consensus-derived injury assessment tool.

Introduction: Major trauma centre (MTC) care has been associated with improved outcomes for injured patients. English ambulance services and trauma networks currently use a range of triage tools to select patients for bypass to MTCs. A standardised national triage tool may improve triage accuracy, cost-effectiveness and the reproducibility of decision-making. Methods: We conducted an expert consensus process to derive and develop a major trauma triage tool for use in English trauma networks. A web-based Delphi survey was conducted to identify and confirm candidate triage tool predictors of major trauma. Facilitated roundtable consensus meetings were convened to confirm the proposed triage tool's purpose, target diagnostic threshold, scope, intended population and structure, as well as the individual triage tool predictors and cut points. Public and patient involvement (PPI) focus groups were held to ensure triage tool acceptability to service users. Results: The Delphi survey reached consensus on nine triage variables in two domains, from 109 candidate variables after three rounds. Following a review of the relevant evidence during the consensus meetings, iterative rounds of discussion achieved consensus on the following aspects of the triage tool: reference standard, scope, target diagnostic accuracy and intended population. A three-step tool comprising physiology, anatomical injury and clinical judgement domains, with triage variables assessed in parallel, was recommended. The triage tool was received favourably by PPI focus groups. Conclusions: This paper presents a new expert consensus derived major trauma triage tool with defined purpose, scope, intended population, structure, constituent variables, variable definitions and thresholds. Prospective evaluation is required to determine clinical and cost-effectiveness, acceptability and usability.

γH2AX in mouse embryonic stem cells: Distribution during differentiation and following γ-irradiation.

Phosphorylated histone H2AX (γH2AX) represents a sensitive molecular marker of DNA double-strand breaks (DSBs) and is implicated in stem cell biology. We established a model of mouse embryonic stem cell (mESC) differentiation and examined the dynamics of γH2AX foci during the process. Our results revealed high numbers of γH2AX foci in undifferentiated mESCs, decreasing as the cells differentiated towards the endothelial cell lineage. Notably, we observed two distinct patterns of γH2AX foci: the typical discrete γH2AX foci, which colocalize with the transcriptionally permissive chromatin mark H3K4me3, and the less well-characterized clustered γH2AX regions, which were only observed in intermediate progenitor cells. Next, we explored responses of mESCs to γ-radiation (137Cs). Following exposure to γ-radiation, mESCs showed a reduction in cell viability and increased γH2AX foci, indicative of radiosensitivity. Despite irradiation, surviving mESCs retained their differentiation potential. To further exemplify our findings, we investigated neural stem progenitor cells (NSPCs). Similar to mESCs, NSPCs displayed clustered γH2AX foci associated with progenitor cells and discrete γH2AX foci indicative of embryonic stem cells or differentiated cells. In conclusion, our findings demonstrate that γH2AX serves as a versatile marker of DSBs and may have a role as a biomarker in stem cell differentiation. The distinct patterns of γH2AX foci in differentiating mESCs and NSPCs provide valuable insights into DNA repair dynamics during differentiation, shedding light on the intricate balance between genomic integrity and cellular plasticity in stem cells. Finally, the clustered γH2AX foci observed in intermediate progenitor cells is an intriguing feature, requiring further exploration.

Leishmania braziliensis enhances monocyte responses to promote anti-tumor activity.

Innate immune cells can undergo long-term functional reprogramming after certain infections, a process called trained immunity (TI). Here, we focus on antigens of Leishmania braziliensis, which induced anti-tumor effects via trained immunity in human monocytes. We reveal that monocytes exposed to promastigote antigens of L. braziliensis develop an enhanced response to subsequent exposure to Toll-like receptor (TLR)2 or TLR4 ligands. Mechanistically, the induction of TI in monocytes by L. braziliensis is mediated by multiple pattern recognition receptors, changes in metabolism, and increased deposition of H3K4me3 at the promoter regions of immune genes. The administration of L. braziliensis exerts potent anti-tumor capabilities by delaying tumor growth and prolonging survival of mice with non-Hodgkin lymphoma. Our work reveals mechanisms of TI induced by L. braziliensis in vitro and identifies its potential for cancer immunotherapy.

Glycemic memories and the epigenetic component of diabetic nephropathy.

A strong case for the deregulation of epigenetic chromatin modifications in the development and progression of various chronic complications of diabetes has emerged from recent experimental observations. Clinical trials of type 1 and type 2 diabetes patients highlight the importance of early and intensive treatment and the prolonged damage of hyperglycemia on organs such as the kidney. The functional relationship between the regulation of chromatin architecture and persistent gene expression changes conferred by prior hyperglycemia represents an important avenue of investigation for explaining diabetic nephropathy. While several studies implicate epigenetic changes at the chromatin template in the deregulated gene expression associated with diabetic nephropathy, the molecular determinants of metabolic memory in renal cells remain poorly understood. There is now strong evidence from experimental animals and cell culture of persistent glucose-driven changes in vascular endothelial gene expression that may also have relevance for the microvasculature of the kidney. Exploration of epigenetic mechanisms underlying the hyperglycemic cue mediating persistent transcriptional changes in renal cells holds novel therapeutic potential for diabetic nephropathy.

Metaboloepigenetics in cancer, immunity, and cardiovascular disease.

The influence of cellular metabolism on epigenetic pathways is well documented but misunderstood. Scientists have long known of the metabolic impact on epigenetic determinants. More often than not, that title role for DNA methylation was portrayed by the metabolite S-adenosylmethionine. Technically speaking, there are many other metabolites that drive epigenetic processes that instruct seemingly distant-yet highly connect pathways-and none more so than our understanding of the cancer epigenome. Recent studies have shown that available energy links the extracellular environment to influence cellular responses. This focused review examines the recent interest in epigenomics and casts cancer, metabolism, and immunity in unfamiliar roles-cooperating. There are not only language lessons from cancer research, we have come round to appreciate that reaching into areas previously thought of as too distinct are also object lessons in understanding health and disease. The Warburg effect is one such signature of how glycolysis influences metabolic shift during oncogenesis. That shift in metabolism-now recognized as central to proliferation in cancer biology-influences core enzymes that not only control gene expression but are also central to replication, condensation, and the repair of nucleic acid. These nuclear processes rely on metabolism, and with glucose at centre stage, the role of respiration and oxidative metabolism is now synonymous with the mitochondria as the powerhouses of metaboloepigenetics. The emerging evidence for metaboloepigenetics in trained innate immunity has revealed recognizable signalling pathways with antecedent extracellular stimulation. With due consideration to immunometabolism, we discuss the striking signalling similarities influencing these core pathways. The immunometabolic-epigenetic axis in cardiovascular disease has deeply etched connections with inflammation, and we examine the chromatin template as a carrier of epigenetic indices that determine the expression of genes influencing atherosclerosis and vascular complications of diabetes.

Immune modulatory effects of progesterone on oxLDL-induced trained immunity in monocytes.

Atherosclerotic cardiovascular diseases (CVD) are among the leading causes of death in the world. Monocyte-derived macrophages are key players in the pathophysiology of atherosclerosis. Innate immune memory following exposure of monocytes to atherogenic compounds, such as oxidized low-density lipoproteins (oxLDL), termed trained immunity, can contribute to atherogenesis. The current study aimed to elucidate intracellular mechanisms of oxLDL-induced trained immunity. Using untargeted intracellular metabolomics in isolated human primary monocytes, we show that oxLDL-induced trained immunity results in alterations in the balance of intracellular steroid hormones in monocytes. This was reflected by a decrease in extracellular progesterone concentrations following LPS stimulation. To understand the potential effects of steroid hormones on trained immunity, monocytes were costimulated with oxLDL and the steroid hormones progesterone, hydrocortisone, dexamethasone, ß-estradiol, and dihydrotestosterone. Progesterone showed a unique ability to attenuate the enhanced TNFα and IL-6 production following oxLDL-induced trained immunity. Single nucleotide polymorphisms in the nuclear glucocorticoid, progesterone, and mineralocorticoid receptor were shown to correlate with ex vivo oxLDL-induced trained immunity in 243 healthy volunteers. Pharmacologic inhibition experiments revealed that progesterone exerts the suppression of TNFα in trained immunity via the nuclear glucocorticoid and mineralocorticoid receptors. Our data show that progesterone has a unique ability to suppress oxLDL-induced trained immunity. We hypothesize that this effect might contribute to the lower incidence of CVD in premenopausal women.

Injured patients who would benefit from expedited major trauma centre care: a consensus-based definition for the United Kingdom.

INTRODUCTION: Despite the importance of treating the 'right patient in the right place at the right time', there is no gold standard for defining which patients should receive expedited major trauma centre (MTC) care. This study aimed to define a reference standard applicable to the United Kingdom (UK) National Health Service major trauma networks. METHODS: A one-day facilitated roundtable expert consensus meeting was conducted at the University of Sheffield, UK, in September 2019. An expert panel of 17 clinicians was purposively sampled, representing all specialities relevant to major trauma management. A consultation process was subsequently held using focus groups with Public and Patient Involvement (PPI) representatives to review and confirm the proposed reference standard. RESULTS: Four reference standard domains were identified, comprising: need for critical interventions; presence of significant individual anatomical injuries; burden of multiple minor injuries; and important patient attributes. Specific criteria were defined for each domain. PPI consultation confirmed all aspects of the reference standard. A coding algorithm to allow operationalisation in Trauma Audit and Research Network data was also formulated, allowing classification of any case submitted to their database for future research. CONCLUSIONS: This reference standard defines which patients would benefit from expedited MTC care. It could be used as the target for future pre-hospital injury triage tools, for setting best practice tariffs for trauma care reimbursement and to evaluate trauma network performance. Future research is recommended to compare patient characteristics, management and outcomes of the proposed definition with previously established reference standards.

Diagnostic accuracy of prehospital triage tools for identifying major trauma in elderly injured patients: A systematic review.

BACKGROUND: Older adults with major trauma are frequently undertriaged, increasing the risk of preventable morbidity and mortality. The aim of this systematic review was to evaluate the diagnostic performance of prehospital triage tools to identify suspected elderly trauma patients in need of specialized trauma care. METHODS: Several electronic databases (including MEDLINE, EMBASE, and the Cochrane Library) were searched from inception to February 2019. Prospective or retrospective diagnostic studies were eligible if they examined prehospital triage tools as index tests (either scored theoretically using observed patient variables or evaluated according to actual paramedic transport decisions) compared with a reference standard for major trauma in elderly adults who require transport by paramedics following injury. Selection of studies, data extraction, and risk of bias assessments using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool were undertaken independently by at least two reviewers. Narrative synthesis was used to summarize the findings. RESULTS: Fifteen studies met the inclusion criteria, with 11 studies examining theoretical accuracy, three evaluating real-life transport decisions, and one assessing both (of 21 individual index tests). Estimates for sensitivity and specificity were highly variable with sensitivity estimates ranging from 19.8% to 95.5% and 57.7% to 83.3% for theoretical accuracy and real life triage performance, respectively. Specificity results were similarly diverse ranging from 17.0% to 93.1% for theoretical accuracy and 46.3% to 78.9% for actual paramedic decisions. Most studies had unclear or high risk of bias and applicability concerns. There were no obvious differences between different triage tools, and findings did not appear to vary systematically with major trauma prevalence, age, alternative reference standards, study designs, or setting. CONCLUSION: Existing prehospital triage tools may not accurately identify elderly patients with serious injury. Future work should focus on more relevant reference standards, establishing the best trade-off between undertriage and overtriage, optimizing the role prehospital clinician judgment, and further developing geriatric specific triage variables and thresholds. LEVEL OF EVIDENCE: Systematic review, level III.