Burns are a global issue that can result in lifelong multimorbidities and disproportionately affect people in low-resource settings. Prioritising research of importance to patients and health-care professionals improves evidence-based care. This prioritisation setting partnership was undertaken in global burn care (focusing on thermal non-electrical burns) by establishing a James Lind Alliance research priority setting partnership. Over 2 years, two online multilingual surveys with patients, carers, and clinicians, 16 interviews, and a virtual priority setting workshop were conducted to identify and prioritise questions for research. Survey responses were received from participants in 88 countries (1617 survey one respondents; 630 survey two respondents). A short-list of 19 research priorities were ranked at an online workshop attended by 28 participants (14 health-care professionals, ten burn survivors, and four carers or advocates) from 15 countries to produce the final top ten research priorities. These priorities provide opportunities for researchers, funders, and clinicians to shape the future of burns research and improve burns care globally.

Early wound debridement for deep partial and full thickness burns reduces infection risk, facilitates prompt evaluation of the wound bed and shortens hospital admission. 1 Xiao-Wu W. Herndon D.N. Spies M. Sanford A.P. Wolf S.E. Effects of delayed wound excision and grafting in severely burned children. Arch Surg. 2002; https://doi.org/10.1001/archsurg.137.9.1049 Crossref PubMed Scopus (131) Google Scholar Current standard of care (SOC) for burn debridement is surgical excision. Disadvantages of this technique include blood loss and excision of viable tissue. 2 Rosenberg L. Krieger Y. Bogdanov-Berezovski A. Silberstein E. Shoham Y. Singer A.J. A novel rapid and selective enzymatic debridement agent for burn wound management: A multi-center RCT. BURNS. 2014; 40: 466-474https://doi.org/10.1016/j.burns.2013.08.013 Crossref PubMed Scopus (155) Google Scholar

Monocytes but not unstimulated lymphocytes adhered to human neurons and astrocytes in primary culture, as demonstrated by double labeling. The expression of VCAM-1 was higher on neurons than on astrocytes, whereas that of beta 1, alpha 1, alpha 2, alpha 4 and alpha 5 chains from the integrins and of ICAM-1 was identical on both types of cells. The expression on neurons of ICAM-1, but not of integrins, was up-regulated by exogenous tumor necrosis factor (TNF) alpha, interleukin (IL)-1 alpha and interferon (IFN)-gamma. The same was observed on astrocytes associated with a sharp increase in the expression of VCAM-1. Adhesion between monocytes and neurons or astrocytes was 80% inhibited by mAbs directed against the CR3 determinant on monocytes or against ICAM-1 on neural cells but not by any of the other mAbs against adhesion proteins that were tested. Finally, the level of endogenous production of IL-1 alpha and TNF alpha was greatly increased after the adhesion of monocytes to CNS cells.

Abstract Study question What trends can be observed in the type, quality and utility of research conducted from 1990-2021 assessing Anti-Mullerian hormone (AMH) in relation to fertility? Summary answer The large majority of AMH-research in relation to fertility is conducted through non-randomised retrospective cohort studies and has limited clinical utility. What is known already The last decades have seen strong increases in in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI), partly due to a delay in childbearing age. In the last 30 years the integral role of AMH in female reproductive function has gained increasing attention. AMH, expressed by follicles in the ovary at levels proportional to the number of growing follicles, is predictive of the ovarian response to stimulation, live birth rate, and time to menopause. In this capacity, AMH is used to predict and maximise the success of ART and estimate the end of a woman’s reproductive lifespan. Study design, size, duration We investigated trends in design/execution of AMH research. We searched Web of Science and PubMed. Inclusion criteria were a primary research article conducted in humans, investigating AMH in relation to fertility. Basic research, e.g. investigations of the mechanism of action of AMH, were also included. Animal studies, AMH unrelated to fertility (e.g., as an anti-cancer drug), and studies using AMH as a surrogate measurement of ovarian reserve in the context of other research were excluded. Participants/materials, setting, methods After inclusion, we extracted the question being addressed, the country, region (based on the World Health Organisation (WHO) world region classifications), funding, study design and direction of data collection, sample size and its calculation, and statement of data availability. Finally, using a checklist of features thought to reflect the clinical utility of a study, a sub-group of research was assessed. These features include problem base, context placement, information gain, pragmatism, patient-centredness, feasibility and transparency. Main results and the role of chance We detected 701 studies on AMH in relation to fertility published between 1990 and 2021. The majority of research is conducted in the European (48%) and Western Pacific (21%) regions, closely followed by the American region (18%). We identified 18/701 (2.5%) studies as randomized controlled trials. A non-randomised cohort design was used in 541/701 (77%) of studies, and of these 541, 68% were retrospective. Furthermore, excluding in vitro and case-report studies, 284/529 (55%) studies are prognostic in nature, with arguably insufficient associative evidence (42%) in support of the widespread use of AMH as a prognostic tool. When we assessed the clinical utility of AMH research, studies performed poorly on information gain and transparency. In terms of information gain, only 62/701 (9%) studies contained any mention of a sample size calculation. Many studies reported on outcomes such as clinical/biochemical pregnancy and oocytes retrieved, with live birth being the primary outcome in only 35/701 (5%) studies assessed. For transparency, 47% of the studies assessed failed to mention a funding source, and 93% made no mention of data availability. Limitations, reasons for caution A limitation is that only two databases were searched, and inclusion of more studies may have altered the overall snapshot of the current state of research. Furthermore, information was extracted from the abstract where possible before the full article was addressed, which may have impacted the extraction/classification of studies. Wider implications of the findings These findings suggest that research and publication systems require changes to promote better research. Encouraging large-scale, multi-national, clinical trials and more data-sharing will produce more informative studies and greater improvements to clinical care. Reduced emphasis on importance of being the lead, corresponding or senior author may also encourage more collaboration. Trial registration number Not-applicable

AbstractBacterial cell division is a complex process requiring the coordination of multiple components, to allow the appropriate spatial and temporal control of septum formation and cell scission. Peptidoglycan (PG) is the major structural component of the septum, and our recent studies in the human pathogenStaphylococcus aureushave revealed a complex, multi- stage PG architecture that develops during septation. Penicillin binding proteins (PBPs) are essential for the final steps of PG biosynthesis – their transpeptidase activity links together the peptide sidechain of nascent glycan strands together. PBP1 is required for cell division inS. aureusand here we demonstrate that it has multiple essential functions associated with its enzymatic activity and as a regulator of division. Loss of PBP1, or just its C-terminal PASTA domains, results in cessation of division at the point of septal plate formation. The PASTA domains can bind PG and thus coordinate the cell division process. The transpeptidase activity of PBP1 is also essential but its loss leads to a strikingly different phenotype of thickened and aberrant septa, which is phenocopied by the morphological effects of adding the PBP1-specificβ-lactam, meropenem. Together these results lead to a model for septal PG synthesis where PBP1 enzyme activity is responsible for the characteristic architecture of the septum and PBP1 protein molecules coordinate cell division allowing septal plate formation.

Bacterial cell division is a complex process requiring the coordination of multiple components, to allow the appropriate spatial and temporal control of septum formation and cell scission. Peptidoglycan (PG) is the major structural component of the septum, and our recent studies in the human pathogen Staphylococcus aureus have revealed a complex, multi- stage PG architecture that develops during septation. Penicillin binding proteins (PBPs) are essential for the final steps of PG biosynthesis – their transpeptidase activity links together the peptide sidechain of nascent glycan strands together. PBP1 is required for cell division in S. aureus and here we demonstrate that it has multiple essential functions associated with its enzymatic activity and as a regulator of division. Loss of PBP1, or just its C-terminal PASTA domains, results in cessation of division at the point of septal plate formation. The PASTA domains can bind PG and thus coordinate the cell division process. The transpeptidase activity of PBP1 is also essential but its loss leads to a strikingly different phenotype of thickened and aberrant septa, which is phenocopied by the morphological effects of adding the PBP1-specific β -lactam, meropenem. Together these results lead to a model for septal PG synthesis where PBP1 enzyme activity is responsible for the characteristic architecture of the septum and PBP1 protein molecules coordinate cell division allowing septal plate formation. ### Competing Interest Statement The authors have declared no competing interest.

A complex multisubunit repair using three different flaps J. Boggs, J. Ralph, C. O’Grady and R. Barry St James’ Hospital, Dublin, Ireland Mohs micrographic excision of nonmelanoma skin cancers resulting in composite defects, including two or more facial subunits, involving the medial cheek, ala, apical lip and upper cutaneous lip pose, can result in challenging surgical defects to reconstruct. Key considerations include proper delineation of the affected units/subunits, restoring volume to the ala and recreation of the natural concavities of the alar crease and nasolabial fold. In addition, care must be taken in relation to free-margin positions of the ala and upper vermillion lip. There are many options available to the surgeon, but consideration of patient comorbidity and expectations should be accounted for. Reconstructive options include locoregional skin flaps, complex multistage interpolated flaps or skin grafting. Given the complex topography of this area, when faced with reconstruction of defects involving the alar–facial sulcus and upper cutaneous lip, multiple flaps are often necessary to recreate its natural appearance and symmetry, while also preserving the alar crease and melolabial sulcus. We highlight the merits of a complex subunit repair using a fat hinge flap, a 180 twisted island pedicle flap (IPF) and a V to Y flap. A 55year-old presented with an 18 9 13 mm nodular and infiltrating basal cell carcinoma involving the right nasal ala and apical lip. Three stages of Mohs micrographic surgery led to tumour-free margins and resulted in a surgical defect measuring 28 9 23 mm. The defect was complex involving the right medial cheek, ala, apical lip and upper cutaneous lip. An incision was made along the lateral wound margin, and a fat hinge flap was elevated and placed into the deep apical lip defect and secured. An IPF flap from the right nasal sidewall was created by the entire flap being incised through the skin while maintaining the integrity of underlying subcutaneous fat, muscle and vasculature. The flap was then transposed over the intervening tissue and twisted 180 to recreate the right alar base. The secondary defect on the right nasal sidewall was closed primarily. A V to Y flap was elevated from the lateral chin extending onto the medial cheek to close the residual defect. We have found these flaps to be a useful reconstruction for large deep surgical defects on the medial cheek, ala, apical lip and upper cutaneous lip. It results in an aesthetically acceptable surgical outcome and is a one-stage procedure, which may be preferable for some patients. DS12 Replacing the need for skin grafting in small surgical excision wounds L. Hook, D. Barnes, J. Sullivan, A. Reid, R. Tousis, C. Morgan, A. Belgi, S. Booth and B. Dheansa Smart Matrix Limited, London, UK; St Andrew’s Burns and Plastics Centre, Broomfield Hospital, Chelmsford, UK; Department of Plastic Surgery and Burns Wythenshawe Hospital, Manchester, UK; Poole General Hospital, Poole, UK; and McIndoe Burn Centre Queen Victoria Hospital, East Grinstead, UK Smart Matrix is a novel fibrin/alginate dermal replacement scaffold developed for the treatment of full-thickness wounds without the need for a skin graft. The safety and performance of Smart Matrix in the treatment of surgical excision wounds arising from the excision of nonmelanoma skin cancer (NMSC) is currently being assessed in an ongoing clinical investigation. Recruitment into the trial is complete with 32 patients being treated at four clinical centres. The average age of the patients is 75 years (range 54–90) and all lesions have been on either the lower leg or scalp. The average excision wound size is 10 5 cm (range 3 7–25 5). Patients are assessed for safety parameters, such as infection and seroma, and the need for a ‘rescue’ skin graft. Performance parameters include time to healing and scar quality using Patient and Observer Scar Assessment Scale and Vancouver Scar Scale scores. Patients are followed-up for 12 months. Surgeon assessment of the device is also recorded. The trial is funded by Smart Matrix Limited. To date, 25 patients have completed the study. All wounds have healed with minimal complications: infection, seroma and haematoma rates are within expected levels for this type of surgery. Importantly, no patients have required a skin graft or any further surgical intervention. Healed wounds show a favourable scar outcome, in particular with reference to contour and contraction. Surgeons report that the device is simple to use and no specialist training is required. Patient satisfaction is high, with the primary advantages being reported as not having to have a donor site wound and the good cosmetic outcome of the scar. Several patients who have presented with second lesions during the study have asked to be treated with Smart Matrix again rather than have a skin graft. Smart Matrix has a good safety and performance profile in the treatment of NMSC excision wounds without the use of a skin graft. Although healing times are slower than would be expected for a skin-grafted wound, this has not been associated with any increase in wound complications, such as infections, or compromise on scar quality. In fact, wounds treated with Smart Matrix result in a good cosmetic and functional outcome, which in many cases is better than would be expected for a skin-grafted wound. Smart Matrix has the potential to offer an alternative to skin grafting for surgical excision wounds with consequent benefits to the patient of avoiding a donor site wound and its associated morbidity. It may also have application in small traumatic skin injuries or burns and in nonspecialist settings.

Burn Wound Infection (BWI) is difficult to define and detect before it manifests with clear clinical symptoms. In this paper, an ex vivo study of a prototype BWI detecting wound dressing is reported. Consenting patients with burns were recruited from four burns services in the United Kingdom, their burn infection state recorded at time of recruitment and retrospectively following treatment. Their wound dressings were used as a source of inoculating bacteria to create an ex vivo biofilm model in the laboratory with reasonable fidelity to the original microbial state of their wound. The prototype infection detecting wound dressing, which responds to cytolytic toxins secreted by bacteria, was placed on the ex vivo biofilm and the response of the dressing correlated with the clinical decision on the patient’s wound infection state. The study illustrated a number of broader issues with clinical BWI diagnosis, notably the absence of objective diagnostic criteria: a ‘reference standard’ for BWI. The absence of such a reference standard made analysis of the relationship between the dressing response and BWI diagnosis challenging, however a point estimate of 68% sensitivity from the study suggests the potential future utility of using a sensor which detects secreted bacterial virulence factors to assist in BWI diagnosis.

Wound infection is commonly observed after surgery and trauma but is difficult to diagnose and poorly defined in terms of objective clinical parameters. The assumption that bacteria in a wound correlate with infection is false; all wounds contain microorganisms, but not all wounds are clinically infected. This makes it difficult for clinicians to determine true wound infection, especially in wounds with pathogenic biofilms. If an infection is not properly treated, pathogenic virulence factors, such as rhamnolipids from Pseudomonas aeruginosa, can modulate the host immune response and cause tissue breakdown. Life-threatening sepsis can result if the organisms penetrate deep into host tissue. This communication describes the sensor development for five important clinical microbial pathogens commonly found in wounds: Staphylococcus aureus, P. aeruginosa, Candida albicans/auris, and Enterococcus faecalis (the SPaCE pathogens). The sensor contains liposomes encapsulating a self-quenched fluorescent dye. Toxins, expressed by SPaCE infecting pathogens in early-stage infected wounds, break down the liposomes, triggering dye release, thus changing the sensor color from yellow to green, an indication of infection. Five clinical species of bacteria and fungi, up to 20 strains each (totaling 83), were grown as early-stage biofilms in ex vivo porcine burn wounds. The biofilms were then swabbed, and the swab placed in the liposome suspension. The population density of selected pathogens in a porcine wound biofilm was quantified and correlated with colorimetric response. Over 88% of swabs switched the sensor on (10(7)-10(8) CFU/swab). A pilot clinical study demonstrated a good correlation between sensor switch-on and early-stage wound infection.

Introduction: Raised serum lactate is an established manifestation of anaerobic metabolism and reduced tissue perfusion in the context of critical illness. Lactate is an often used parameter in the evaluation of the critically ill patient and their response to intervention. Raised levels are associated with increased mortality and adverse outcomes in general surgical, septic and trauma patients. We have observed pathologically (>2 mmol/L) raised serum lactate levels in patients undergoing major head and neck cancer surgery. There is limited data concerned with an association between raised serum lactate levels and adverse outcomes in free tissue transfer in head and neck cancer patients.

BackgroundWound infection in burn patients is common and has an impact on outcomes. There is no objective method to diagnose infection at point of care (PoC). Early diagnosis prevents progression to sepsis. Diagnostic subjectivity supports over-diagnosis, unnecessary hospitalization, and antibiotic overuse.AimThis pilot study aimed to investigate the accuracy of a novel PoC wound infection diagnostic in burn patients.MethodsWe produced, and in vitro tested, a PoC diagnostic for early wound infection diagnosis. The prototype SPaCE diagnostic uses a patented lipid vesicle suspension into which a clinical swab is placed. The diagnostic delivers a colour-response to Staphylococcus aureus, Pseudomonas aeruginosa, Candida species and Enterococcus faecalis at toxin release. A pilot clinical diagnostic accuracy study was undertaken. The reference standard was a retrospective decision made by an expert clinical panel using routinely available data.FindingsData was available from 33 of 34 patients. Of these, 52% were considered to have a wound infection, 42% not, and two (6%) were equivocal. The diagnostic results showed 24% were infected, 42% were not and 33% produced intermediate results. Agreement between clinical judgement and diagnostic result, assessed using a weighted Kappa, was 0.591 suggesting moderate agreement. If the intermediate results were excluded, 22 sets of data with definitive results achieved a Kappa statistic of 0.81 suggesting ‘almost perfect’ agreement. Sensitivity and specificity were 57% (8/14) and 71% (12/17), respectively.ConclusionThis pilot study provided evidence that the SPaCE diagnostic could provide valuable and timely data to support clinical decision-making at PoC for wound infection.

INTRODUCTION:Evidence-based interventions are needed to treat burn wound infection (BWI). Evidence syntheses have been limited by heterogeneity of indicators used to report BWI across trials. Consistent reporting of BWI would be facilitated by an agreed minimum set of indicators. The Infection Consensus in Burns study aimed to achieve expert consensus about a core indicator set (CIS) for BWI.METHODS:The CIS was established through development of a long list of BWI indicators identified from a systematic review and expert input. In a Delphi survey, UK expert participants rated the indicators according to use in everyday practice, importance for diagnosis and frequency of observation in patients with BWI. Indicators were included in the CIS if ≥75% of participants agreed it was important for diagnosis and used in everyday practice, and ≥50% of participants rated it as frequently observed in patients with BWI.RESULTS:One hundred and ninety-five indicators were identified from the systematic review and reduced to 29 survey items through merging of items with the same meaning. Seventy-five UK experts participated in the Delphi survey. Following a single survey round and a consensus meeting with an expert panel, four items were included in the CIS: pyrexia, spreading erythema, change in white cell count, and presence of pathogenic microbes.DISCUSSION AND CONCLUSIONS:To facilitate evidence synthesis, a single-country systematic, expert-informed approach was taken to develop a CIS to be reported consistently across trials reporting BWI as an outcome. Future work requires verification of the CIS with international experts.

The use of robust evidence is a key component of providing high quality care to patients. Synthesised evidence to support clinical decision-making is lacking for many aspects of clinical burn care. Identifying the most important areas of care that lack high quality evidence and requires research is necessary, as funding for primary research is limited. Priority setting research studies are a joint endeavour between patients, carers and clinicians to identify and rank topics for research in a healthcare area in order to reduce research waste. Such an exercise has yet to be undertaken in burns. The aim of this paper is to outline the importance of research prioritisation in burn care, to discuss how it facilitates the maximum benefit from limited research funding and to explain the methodologies used.

Introduction Systematic reviews of high-quality randomised controlled trials are necessary to identify effective interventions to impact burn wound infection (BWI) outcomes. Evidence synthesis requires that BWI is reported in a consistent manner. Cochrane reviews investigating interventions for burns report that the indicators used to diagnose BWI are variable or not described, indicating a need to standardise reporting. BWI is complex and diagnosed by clinician judgement, informed by patient-reported symptoms, clinical signs, serum markers of inflammation and bacteria in the wound. Indicators for reporting BWI should be important for diagnosis, frequently observed in patients with BWI and assessed as part of routine healthcare. A minimum (core) set of indicators of BWI, reported consistently, will facilitate evidence synthesis and support clinical decision-making. Aims The Infection Consensus in Burns study aims to identify a core indicator set for reporting the diagnosis of BWI in research studies. Methods (1) Evidence review: a systematic review of indicators used in trials and observational studies reporting BWI outcomes to identify a long list of candidate indicators; (2) refinement of the long list into a smaller set of survey questions with an expert steering group; (3) a two-round Delphi survey with 100 multidisciplinary expert stakeholders, to achieve consensus on a short list of indicators; (4) a consensus meeting with expert stakeholders to agree on the BWI core indicator set. Ethics and dissemination Participants will be recruited through professional bodies, such that ethical approval from the National Health Service (NHS) Health Research Authority (HRA) is not needed. The core indicator set will be disseminated through peer-reviewed publication, co-production with journal editors, research funders and professional bodies, and presentation at national conferences. PROSPERO registration number CRD42018096647.

The metabolism of carbohydrate polymers drives microbial diversity in the human gut microbiome. The selection pressures in this environment have spurred the evolution of a complex reservoir of microbial genes encoding carbohydrate-active enzymes (CAZymes). Previously, we have shown that the human gut bacterium Bacteroides thetaiotaomicron (Bt) can depolymerize the most structurally complex glycan, the plant pectin rhamnogalacturonan II (RGII), commonly found in the human diet. Previous investigation of the RGII-degrading apparatus in Bt identified BT0997 as a new CAZyme family, classified as glycoside hydrolase 138 (GH138). The mechanism of substrate recognition by GH138, however, remains unclear. Here, using synthetic substrates and biochemical assays, we show that BT0997 targets the d-galacturonic acid-α-1,2-l-rhamnose linkage in chain A of RGII and that it absolutely requires the presence of a second d-galacturonic acid side chain (linked β-1,3 to l-rhamnose) for activity. NMR analysis revealed that BT0997 operates through a double displacement retaining mechanism. We also report the crystal structure of a BT0997 homolog, BPA0997 from Bacteroides paurosaccharolyticus, in complex with ligands at 1.6 Å resolution. The structure disclosed that the enzyme comprises four domains, including a catalytic TIM (α/β)8 barrel. Characterization of several BT0997 variants identified Glu-294 and Glu-361 as the catalytic acid/base and nucleophile, respectively, and we observed a chloride ion close to the active site. The three-dimensional structure and bioinformatic analysis revealed that two arginines, Arg-332 and Arg-521, are key specificity determinants of BT0997 in targeting d-galacturonic acid residues. In summary, our study reports the first structural and mechanistic analyses of GH138 enzymes.

Bacteria are surrounded by a complex cell envelope made up of one or two membranes supplemented with a layer of peptidoglycan (PG). The envelope is responsible for the protection of bacteria against lysis in their oft-unpredictable environments and it contributes to cell integrity, morphology, signaling, nutrient/small-molecule transport, and, in the case of pathogenic bacteria, host-pathogen interactions and virulence. The cell envelope requires considerable remodeling during cell division in order to produce genetically identical progeny. Several proteinaceous machines are responsible for the homeostasis of the cell envelope and their activities must be kept coordinated in order to ensure the remodeling of the envelope is temporally and spatially regulated correctly during multiple cycles of cell division and growth. This review aims to highlight the complexity of the components of the cell envelope, but focusses specifically on the molecular apparatuses involved in the synthesis of the PG wall, and the degree of cross talk necessary between the cell division and the cell wall remodeling machineries to coordinate PG remodeling during division. The current understanding of many of the proteins discussed here has relied on structural studies, and this review concentrates particularly on this structural work.

OBJECTIVES:To evaluate the impact of low-friction (LF) bedding on graft loss in an acute burn care setting, and to examine the feasibility and costs of using LF bedding compared with standard care. DESIGN:Proof of concept before and after study with feasibility of delivering the intervention. SETTING:Three burns services within two UK hospital trusts. PARTICIPANTS:Inclusion criteria were patients older than 4 weeks, who received a skin graft after burn injury and were admitted overnight. The comparator cohort were eligible patients admitted in a 12-month period before the intervention. INTERVENTION:Introduction of LF sheets and pillowcases during a 15-month period. OUTCOME MEASURES:For proof of concept, the LF and comparator cohorts were compared in terms of number of regrafting operations (primary), percentage graft loss, hospital length of stay (LoS) and LoS cost (secondary). Feasibility outcomes were practicality and safety of using LF bedding. RESULTS:131 patients were eligible for the LF cohort and 90 patients for the comparator cohort. Although the primary outcome of the proportion needing regrafting was halved in the LF cohort, the confidence interval (CI) crossed 1 (OR (95% CI): 0.56 (0.16 to 1.88)). Partial graft loss (any loss) was significantly reduced in the LF cohort (OR (95% CI): 0.27 (0.14, 0.51)). Inpatient LoS was no different between the two cohorts (difference in median days (95% CI): 0 (-2 to 1)), and the estimated difference in LoS cost was £-1139 (-4829 to 2551). Practical issues were easily resolved, and no safety incidents occurred while patients were nursed on LF bedding. CONCLUSIONS:LF bedding is safe to use in burned patients with skin grafts and we have shown proof of concept for the intervention. Further economic modelling is required to see if an appropriately powered randomised control trial would be worthwhile or if roll out across the National Health Service is justified. TRIAL REGISTRATION NUMBER:ISRCTN82599687.

Biofilm formation in wounds is considered a major barrier to successful treatment, and has been associated with the transition of wounds to a chronic non-healing state. Here we present a novel laboratory model of wound biofilm formation using ex-vivo porcine skin and a custom burn wound array device. The model supports high-throughput studies of biofilm formation and is compatible with a range of established methods for monitoring bacterial growth, biofilm formation, and gene expression. We demonstrate the use of this model by evaluating the potential for bacteriophage to control biofilm formation by Staphylococcus aureus, and for population density dependant expression of S. aureus virulence factors (regulated by the Accessory Gene Regulator, agr) to signal clinically relevant wound infection. Enumeration of colony forming units and metabolic activity using the XTT assay, confirmed growth of bacteria in wounds and showed a significant reduction in viable cells after phage treatment. Confocal laser scanning microscopy confirmed the growth of biofilms in wounds, and showed phage treatment could significantly reduce the formation of these communities. Evaluation of agr activity by qRT-PCR showed an increase in activity during growth in wound models for most strains. Activation of a prototype infection-responsive dressing designed to provide a visual signal of wound infection, was related to increased agr activity. In all assays, excellent reproducibility was observed between replicates using this model.