Intraoperative factors associated with unplanned return to the operating room after emergent hemorrhage control surgery.

BACKGROUND: Unplanned return to the operating room (uROR) is associated with worse outcomes and increased mortality. Little is known regarding intraoperative factors associated with uROR after emergent surgery in trauma patients. The objective of this study was to identify intraoperative factors associated with uROR after emergent hemorrhage control procedures in bleeding trauma patients. METHODS: We used anesthetic record of intraoperative management to perform a retrospective study (2017-2022) of bleeding trauma patients who were taken for an emergent hemorrhage control operation. RESULTS: A total of 225 patients met the inclusion criteria, 46 (20%) had uROR, and 181 (80%) did not. While there was no difference in demographics, mechanism, admission physiology, or time from emergency department to operating room, the uROR patients had a higher Injury Severity Score (30 vs. 25, p = 0.007). While there was no difference in volume of crystalloid infused (3,552 ± 2,279 mL vs. 2,977 ± 2,817 mL, p = 0.20), whole blood (2.2 ± 0.9 vs. 2.0 ± 0.5, p = 0.20), or platelets (11.6 ± 8.6 vs. 9.2 ± 9.0, p = 0.14), the uROR group received more packed red blood cells (11.5 ± 10.6 vs. 7.8 ± 7.5, p = 0.006) and plasma (9.6 ± 8.3 vs. 6.5 ± 6.6, p = 0.01), and more uROR patients received ≥10 U of packed red blood cells (48% vs. 27%, p = 0.006). Damage-control surgery (DCS) was more common in uROR patients (78% vs. 45%, p < 0.0001). After logistic regression, ≥10 U of packed cells in the operating room (4.3 [1.5-12.8], p = 0.009), crystalloid (1.0 [1.0-1.001], p = 0.009), International Normalized Ratio (INR) (7.6 [1.3-45.7], p = 0.03), and DCS (5.7 [1.7-19.1], p = 0.005) were independently associated with uROR. CONCLUSION: Massive transfusion, crystalloid resuscitation, persistent coagulopathy, and DCS are the most significant risk factors for uROR. During hemorrhage control surgery in bleeding trauma patients who receive ≥10 U of blood, providers must maintain a keen focus on minimizing crystalloid and ongoing balanced resuscitation, particularly during damage-control procedures. LEVEL OF EVIDENCE: Retrospective/Descriptive; Level IV.

Structural Racism, Residential Segregation, and Exposure to Trauma: The Persistent Impact of Redlining.

INTRODUCTION: As part of New Deal era federal housing policy, the Home Owners Loan Corporation (HOLC) developed maps grading US neighborhoods by perceived financial security. Neighborhoods with high concentrations of racial and ethnic minorities were deemed financially unstable and denied federal investment, a practice colloquially known as redlining. The aim of this study was to assess the association of historical redlining within Austin, Texas to spatial patterns of penetrating traumatic injury. METHODS: Retrospective cross sectional study utilizing data from violent penetrating trauma admissions between January 1, 2014 - December 31, 2021, at the single Level 1 trauma center in Austin, Texas. Using ArcGIS, addresses where the injury took place were geocoded and spatial joining was used to match them to their corresponding census tract, for which 1935 HOLC financial designations are classified as: "Hazardous", "Definitely Declining", "Still Desirable", "Best", or "Non HOLC Graded". Tracts with designations of "Hazardous" and "Definitely Declining" were categorized as Redlined. The adjusted incidence rate ratio comparing rates of penetrating trauma among historically Redlined vs. Not Redlined and Not Graded census tracts was calculated. RESULTS: 1,404 violent penetrating trauma admissions were identified for the study period, of which 920 occurred within the county of interest. Among these, 5% occurred in census tracts that were Not Redlined, 13% occurred in Redlined tracts, and 82% occurred in non HOLC graded tracts. When adjusting for differences in current census tract demographics and social vulnerability, historically Redlined areas experienced a higher rate of penetrating traumatic injury (Not Redlined IRR = 0.42, 95% CI 0.19-0.94, p = 0.03; Not Graded IRR = 0.15, 95% CI 0.07-0.29, p < 0.001). CONCLUSIONS: Neighborhoods unfavorably classified by HOLC in 1935 continue to experience a higher incidence rate of violent penetrating trauma today. These results underscore the persistent impacts of structural racism and of historical residential segregation policies on exposure to trauma. LEVEL OF EVIDENCE: Level IV, Prognostic and Epidemiological.

The difficult airway in trauma: What you need to know.

ABSTRACT: Airway evaluation and management are generally the first priority for treatment of trauma patients from the prehospital setting throughout their hospital stay. Delay in recognition of an airway problem, or inability to oxygenate or ventilate because of an inadequate airway, will lead to rapid death. Therefore, all clinicians involved in the care of trauma patients should have adequate knowledge of current best practices for airway evaluation and management. In addition, trauma providers should develop and maintain the skills needed to perform various airway maneuvers to establish and maintain an adequate airway. While elective airway management has the luxury of time for thorough airway evaluation, the airway management in the trauma setting does not allow this same opportunity. For this reason, all trauma airways should be presumed to be a difficult airway, and teams should prepare accordingly. This review will summarize the best practices for airway evaluation and management for trauma patients from the prehospital setting through the emergency department.

Statistical estimation of fatal and serious injuries saved by iRAP protocols in 74 countries.

OBJECTIVE: Road traffic crashes cause 1.19 million deaths and millions more injuries annually. The persistently high burden has drawn attention from national and international stakeholders worldwide. Unsafe road infrastructure is one of the major risk factors for traffic safety, particularly in low- and middle-income countries. METHODS: Aiming to eliminate high-risk roads in all countries, the International Road Assessment Programme (iRAP) developed a robust and evidence-based approach to support country transportation agencies. RESULTS: Thus far, the iRAP protocols have been used to collect 1.8 million kilometers of Crash Risk Mapping and 1.5 million kilometers of Star Rating and FSI estimations in 128 countries. Deploying an observational before-and-after (or pre-post) study design, this report estimated the fatal and series injuries (FSI) saved through use of the iRAP protocols. The study is based on 441,753 kilometers of assessed roads from 1,039 projects in 74 countries. Our results show that the implementation of iRAP's proposed countermeasures saves about 159,936 FSI annually. Throughout the lifetime of the implemented countermeasures, a total of 3.2 million FSI could be saved. CONCLUSION: While quantifying the success of the iRAP protocols, our results suggest an opportunity to save many millions more lives on the roads through expanding iRAP implementation to more regions and countries.

Nonoperative Management for Low-Grade Blunt Thoracic Aortic Injury.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) is the standard of care for the treatment of blunt thoracic aortic injury (BTAI) requiring intervention. Data suggest that low-grade BTAI (grade I [intimal tears] or grade II [intramural hematoma]) will resolve spontaneously if treated with nonoperative management (NOM) alone. There has been no comparison specifically between the use of NOM vs TEVAR for low-grade BTAI. We hypothesize that these low-grade injuries can be safely managed with NOM alone. STUDY DESIGN: Retrospective analysis of all patients with a low-grade BTAI in the Aortic Trauma Foundation Registry from 2016 to 2021 was performed. The study population was 1 primary outcome was mortality. Secondary outcomes included complications, ICU length of stay, and ventilator days. RESULTS: A total of 880 patients with BTAI were enrolled. Of the 269 patients with low-grade BTAI, 218 (81%) were treated with NOM alone (81% grade I, 19% grade II), whereas 51 (19%) underwent a TEVAR (20% grade I, 80% grade II). There was no difference in demographic or mechanism of injury in patients with low-grade BTAI who underwent NOM vs TEVAR. There was a difference in mortality between NOM alone and TEVAR (8% vs 18%, p = 0.009). Aortic-related mortality was 0.5% in the NOM group and 4% in the TEVAR group (p = 0.06). Hospital and ICU length of stay and ventilator days were not different between the 2 groups. CONCLUSIONS: NOM alone is safe and appropriate management for low-grade BTAI, with lower mortality and decreased rates of complication when compared with routine initial TEVAR.

Trends in prehospital cervical collar utilization in trauma patients: Closer, but not there yet.

OBJECTIVE: This study aims to assess the change in cervical spine (C-spine) immobilization frequency in trauma patients over time. We hypothesize that the frequency of unnecessary C-spine immobilization has decreased. METHODS: A retrospective chart review of adult trauma patients transported to our American College of Surgeons-verified Level I trauma center from January 1, 2014, to December 31, 2021, was performed. Emergency medical services documentation was manually reviewed to record prehospital physiology and the application of a prehospital cervical collar (c-collar). C-spine injuries were defined as cervical vertebral fractures and/or spinal cord injuries. Univariate and year-by-year trend analyses were used to assess changes in C-spine injury and immobilization frequency. RESULTS: Among 2906 patients meeting inclusion criteria, 12% sustained C-spine injuries, while 88% did not. Patients with C-spine injuries were more likely to experience blunt trauma (95% vs. 68%, p < 0.001), were older (46 years vs. 41 years, p < 0.001), and had higher Injury Severity Scores (31 vs. 18, p < 0.001). They also exhibited lower initial systolic blood pressures (108 mm Hg vs. 119 mm Hg, p < 0.001), lower heart rates (92 beats/min vs. 97 beats/min, p < 0.05), and lower Glasgow Coma Scale scores (9 vs. 11, p < 0.001). In blunt trauma, c-collars were applied to 83% of patients with C-spine injuries and 75% without; for penetrating trauma, c-collars were applied to 50% of patients with C-spine injuries and only 8% without. Among penetrating trauma patients with C-spine injury, all patients either arrived quadriplegic or did not require emergent neurosurgical intervention. The proportion of patients receiving a c-collar decreased in both blunt and penetrating traumas from 2014 to 2021 (blunt-82% in 2014 to 68% in 2021; penetrating-24% in 2014 to 6% in 2021). CONCLUSIONS: Unnecessary C-spine stabilization has decreased from 2014 to 2021. However, c-collars are still being applied to patients who do not need them, both in blunt and in penetrating trauma cases, while not being applied to patients who would benefit from them.

When is it safe to start venous thromboembolism prophylaxis after blunt solid organ injury? A prospective American Association for the Surgery of Trauma multi-institutional trial.

BACKGROUND: The optimal time to initiate venous thromboembolism (VTE) chemoprophylaxis (VTEp) after blunt solid organ injury remains controversial, as VTE mitigation must be balanced against bleeding promulgation. Evidence from primarily small, retrospective, single-center work suggests that VTEp ≤48 hours is safe and effective. This study was undertaken to validate this clinical practice. METHODS: Blunt trauma patients presenting to 19 participating trauma centers in North America were screened over a 1-year study period beginning between August 1 and October 1, 2021. Inclusions were age older than 15 years; ≥1 liver, spleen, or kidney injury; and initial nonoperative management. Exclusions were transfers, emergency department death, pregnancy, and concomitant bleeding disorder/anticoagulation/antiplatelet medication. A priori power calculation stipulated the need for 1,158 patients. Time of VTEp initiation defined study groups: Early (≤48 hours of admission) versus Late (>48 hours). Bivariate and multivariable analyses compared outcomes. RESULTS: In total, 1,173 patients satisfied the study criteria with 571 liver (49%), 557 spleen (47%), and 277 kidney injuries (24%). The median patient age was 34 years (interquartile range, 25-49 years), and 67% (n = 780) were male. The median Injury Severity Score was 22 (interquartile range, 14-29) with Abbreviated Injury Scale Abdomen score of 3 (interquartile range, 2-3), and the median American Association for the Surgery of Trauma grade of solid organ injury was 2 (interquartile range, 2-3). Early VTEp patients (n = 838 [74%]) had significantly lower rates of VTE (n = 28 [3%] vs. n = 21 [7%], p = 0.008), comparable rates of nonoperative management failure (n = 21 [3%] vs. n = 12 [4%], p = 0.228), and lower rates of post-VTEp blood transfusion (n = 145 [17%] vs. n = 71 [23%], p = 0.024) when compared with Late VTEp patients (n = 301 [26%]). Late VTEp was independently associated with VTE (odd ratio, 2.251; p = 0.046). CONCLUSION: Early initiation of VTEp was associated with significantly reduced rates of VTE with no increase in bleeding complications. Venous thromboembolism chemoprophylaxis initiation ≤48 hours is therefore safe and effective and should be the standard of care for patients with blunt solid organ injury. LEVEL OF EVIDENCE: Therapeutic and Care Management; Level III.

Temporal changes in the prehospital management of trauma patients: 2014-2021.

INTRODUCTION: Aggressive prehospital interventions (PHI) in trauma may not improve outcomes compared to prioritizing rapid transport. The aim of this study was to quantify temporal changes in the frequency of PHI performed by EMS. METHODS: Retrospective chart review of adult patients transported by EMS to our trauma center from January 1, 2014 to 12/31/2021. PHI were recorded and annual changes in their frequency were assessed via year-by-year trend analysis and multivariate regression. RESULTS: Between the first and last year of the study period, the frequency of thoracostomy (6% vs. 9%, p â€‹= â€‹0.001), TXA administration (0.3% vs. 33%, p â€‹< â€‹0.001), and whole blood administration (0% vs. 20%, p â€‹< â€‹0.001) increased. Advanced airway procedures (21% vs. 12%, p â€‹< â€‹0.001) and IV fluid administration (57% vs. 36%, p â€‹< â€‹0.001) decreased. ED mortality decreased from 8% to 5% (p â€‹= â€‹0.001) over the study period. On multivariate regression, no PHI were independently associated with increased or decreased ED mortality. CONCLUSION: PHI have changed significantly over the past eight years. However, no PHI were independently associated with increased or decreased ED mortality.

Src- and Abl-family kinases activate spleen tyrosine kinase to maximize phagocytosis and Leishmania infection.

Leishmania spp. are obligate intracellular parasites that must be internalized by phagocytic cells to evade immune responses and cause disease. The uptake of both Leishmania promastigotes (insect-stage parasites) and amastigotes (proliferative-stage parasites in humans and mice) by phagocytes is thought to be mainly host cell driven, not parasite driven. Our previous work indicates that host Src- and Abl-family kinases facilitate Leishmania entry into macrophages and pathogenesis in murine cutaneous leishmaniasis. Here, we demonstrate that host spleen tyrosine kinase (SYK) is required for efficient uptake of Leishmania promastigotes and amastigotes. A Src-family kinase-Abl-family kinase-SYK signaling cascade induces Leishmania amastigote internalization. Finally, lesion size and parasite burden during Leishmania infection is significantly decreased in mice lacking SYK in monocytes or by treatment with the SYK inhibitor entospletinib. In summary, SYK is required for maximal Leishmania uptake by macrophages and disease in mice. Our results suggest potential for treating leishmaniasis using host cell-directed agents.

The more you have, the more you lose: Muscle mass changes in trauma patients with prolonged hospitalizations.

INTRODUCTION: Sarcopenia is a clinically relevant loss of muscle mass with implications of increased morbidity and mortality in adult trauma populations.  Our study aimed to evaluate loss of muscle mass change in adult trauma patients with prolonged hospital stays. METHODS: Retrospective analysis using institutional trauma registry to identify all adult trauma patients with hospital length of stay >14 days admitted to our Level 1 center between 2010 and 2017. All CT images were reviewed, and cross-sectional area (cm2) of the left psoas muscle was measured at the level of the third lumbar vertebral body to determine total psoas area (TPA) and Total Psoas Index (TPI) normalized for patient stature.  Sarcopenia was defined as a TPI on admission below gender specific thresholds of 5.45(cm2/m2) in men and 3.85(cm2/m2) in women.  TPA, TPI, and rates of change in TPI were then evaluated and compared between sarcopenic and non-sarcopenic adult trauma patients. RESULTS: There were 81 adult trauma patients who met inclusion criteria. The average change in TPA was -3.8 cm2 and TPI was -1.3 cm2. On admission, 23% (n = 19) of patients were sarcopenic while 77% (n = 62) were not. Non-sarcopenic patients had a significantly greater change in TPA (-4.9 vs. -0.31, p<0.0001), TPI (-1.7 vs. -0.13, p<0.0001), and rate of decrease in muscle mass (p = 0.0002). 37% of patients who were admitted with normal muscle mass developed sarcopenia during admission.  Older age was the only risk factor independently associated with developing sarcopenia (OR: 1.04, 95%CI 1.00-1.08, p = 0.045). CONCLUSION: Over a third of patients with normal muscle mass at admission subsequently developed sarcopenia with older age as the primary risk factor. Patients with normal muscle mass at admission had greater decreases in TPA and TPI, and accelerated rates of muscle mass loss compared to sarcopenic patients.

Racial and Ethnic Disparity in Prehospital Pain Management for Trauma Patients.

BACKGROUND: Although evidence suggests that racial and ethnic minority (REM) patients receive inadequate pain management in the acute care setting, it remains unclear whether these disparities also occur during the prehospital period. The aim of this study is to assess the impact of race and ethnicity on prehospital analgesic use by emergency medical services (EMS) in trauma patients. STUDY DESIGN: Retrospective chart review of adult trauma patients aged 18 to 89 years old transported by EMS to our American College of Surgeons-verified level 1 trauma center from 2014 to 2020. Patients who identified as Black, Asian, Native American, or Other for race and/or Hispanic or Latino or Unknown for ethnicity were considered REM. Patients who identified as White, non-Hispanic were considered White. Groups were compared in univariate and multivariate analysis. The primary outcome was prehospital analgesic administration. RESULTS: A total of 2,476 patients were transported by EMS (47% White and 53% REM). White patients were older on average (46 years vs 38 years; p < 0.001) and had higher rates of blunt trauma (76% vs 60%; p < 0.001). There were no differences in Injury Severity Score (21 vs 20; p = 0.22). Although REM patients reported higher subjective pain rating (7.2 vs 6.6; p = 0.002), they were less likely to get prehospital pain medication (24% vs 35%; p < 0.001), and that difference remained significant after controlling for baseline characteristics, transport method, pain rating, prehospital hypotension, and payor status (adjusted odds ratio [95% CI], 0.67 [0.47 to 0.96]; p = 0.03). CONCLUSIONS: Patients from racial and ethnic minority groups were less likely to receive prehospital pain medication after traumatic injury than White patients. Forms of conscious and unconscious bias contributing to this inequity need to be identified and addressed.

Reproductive history determines Erbb2 locus amplification, WNT signalling and tumour phenotype in a murine breast cancer model.

Understanding the mechanisms underlying tumour heterogeneity is key to the development of treatments that can target specific tumour subtypes. We have previously targeted CRE recombinase-dependent conditional deletion of the tumour suppressor genes Brca1, Brca2, p53 (also known as Trp53) and/or Pten to basal or luminal oestrogen receptor-negative (ER-) cells of the mouse mammary epithelium. We demonstrated that both the cell-of-origin and the tumour-initiating genetic lesions cooperate to influence mammary tumour phenotype. Here, we use a CRE-activated HER2 orthologue to specifically target HER2/ERBB2 oncogenic activity to basal or luminal ER- mammary epithelial cells and perform a detailed analysis of the tumours that develop. We find that, in contrast to our previous studies, basal epithelial cells are less sensitive to transformation by the activated NeuKI allele, with mammary epithelial tumour formation largely confined to luminal ER- cells. Histologically, most tumours that developed were classified as either adenocarcinomas of no special type or as metaplastic adenosquamous tumours. The former were typically characterized by amplification of the NeuNT/Erbb2 locus; in contrast, tumours displaying squamous metaplasia were enriched in animals that had been through at least one pregnancy and typically had lower levels of NeuNT/Erbb2 locus amplification but had activated canonical WNT signalling. Squamous changes in these tumours were associated with activation of the epidermal differentiation cluster. Thus, in this model of HER2 breast cancer, cell-of-origin, reproductive history, NeuNT/Erbb2 locus amplification and the activation of specific branches of the WNT signalling pathway all interact to drive inter-tumour heterogeneity.

An Antiparasitic Compound from the Medicines for Malaria Venture Pathogen Box Promotes Leishmania Tubulin Polymerization.

The few frontline antileishmanial drugs are poorly effective and toxic. To search for new drugs for this neglected tropical disease, we tested the activity of compounds in the Medicines for Malaria Venture (MMV) "Pathogen Box" against Leishmania amazonensis axenic amastigotes. Screening yielded six discovery antileishmanial compounds with EC50 values from 50 to 480 nM. Concentration-response assays demonstrated that the best hit, MMV676477, had mid-nanomolar cytocidal potency against intracellular Leishmania amastigotes, Trypanosoma brucei, and Plasmodium falciparum, suggesting broad antiparasitic activity. We explored structure-activity relationships (SAR) within a small group of MMV676477 analogs and observed a wide potency range (20-5000 nM) against axenic Leishmania amastigotes. Compared to MMV676477, our most potent analog, SW41, had ∼5-fold improved antileishmanial potency. Multiple lines of evidence suggest that MMV676477 selectively disrupts Leishmania tubulin dynamics. Morphological studies indicated that MMV676477 and analogs affected L. amazonensis during cell division. Differential centrifugation showed that MMV676477 promoted partitioning of cellular tubulin toward the polymeric form in parasites. Turbidity assays with purified Leishmania and porcine tubulin demonstrated that MMV676477 promoted leishmanial tubulin polymerization in a concentration-dependent manner. Analogs' antiparasitic activity correlated with their ability to facilitate purified Leishmania tubulin polymerization. Chemical cross-linking demonstrated binding of the MMV676477 scaffold to purified Leishmania tubulin, and competition studies established a correlation between binding and antileishmanial activity. Our studies demonstrate that MMV676477 is a potent antiparasitic compound that preferentially promotes Leishmania microtubule polymerization. Due to its selectivity for and broad-spectrum activity against multiple parasites, this scaffold shows promise for antiparasitic drug development.

A Systematic Analysis of Mosquito-Microbiome Biosynthetic Gene Clusters Reveals Antimalarial Siderophores that Reduce Mosquito Reproduction Capacity.

Advances in infectious disease control strategies through genetic manipulation of insect microbiomes have heightened interest in microbially produced small molecules within mosquitoes. Herein, 33 mosquito-associated bacterial genomes were mined and over 700 putative biosynthetic gene clusters (BGCs) were identified, 135 of which belong to known classes of BGCs. After an in-depth analysis of the 135 BGCs, iron-binding siderophores were chosen for further investigation due to their high abundance and well-characterized bioactivities. Through various metabolomic strategies, eight siderophore scaffolds were identified in six strains of mosquito-associated bacteria. Among these, serratiochelin A and pyochelin were found to reduce female Anopheles gambiae overall fecundity likely by lowering their blood-feeding rate. Serratiochelin A and pyochelin were further found to inhibit the Plasmodium parasite asexual blood and liver stages in vitro. Our work supplies a bioinformatic resource for future mosquito-microbiome studies and highlights an understudied source of bioactive small molecules.

Comprehensive functional profiling of long non-coding RNAs through a novel pan-cancer integration approach and modular analysis of their protein-coding gene association networks.

BACKGROUND: Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of cellular processes in diseases such as cancer, although the functions of most remain poorly understood. To address this, here we apply a novel strategy to integrate gene expression profiles across 32 cancer types, and cluster human lncRNAs based on their pan-cancer protein-coding gene associations. By doing so, we derive 16 lncRNA modules whose unique properties allow simultaneous inference of function, disease specificity and regulation for over 800 lncRNAs. RESULTS: Remarkably, modules could be grouped into just four functional themes: transcription regulation, immunological, extracellular, and neurological, with module generation frequently driven by lncRNA tissue specificity. Notably, three modules associated with the extracellular matrix represented potential networks of lncRNAs regulating key events in tumour progression. These included a tumour-specific signature of 33 lncRNAs that may play a role in inducing epithelial-mesenchymal transition through modulation of TGFß signalling, and two stromal-specific modules comprising 26 lncRNAs linked to a tumour suppressive microenvironment and 12 lncRNAs related to cancer-associated fibroblasts. One member of the 12-lncRNA signature was experimentally supported by siRNA knockdown, which resulted in attenuated differentiation of quiescent fibroblasts to a cancer-associated phenotype. CONCLUSIONS: Overall, the study provides a unique pan-cancer perspective on the lncRNA functional landscape, acting as a global source of novel hypotheses on lncRNA contribution to tumour progression.

Extracellular vesicle microRNA cargo is correlated with HPV status in oropharyngeal carcinoma.

BACKGROUND: The incidence of human papilloma virus positive (HPV+ ) oropharyngeal squamous cell carcinoma (OPSCC) has increased rapidly in recent decades. These tumours have a favourable outcome compared to HPV-negative (HPV- ) OPSCC. However, HPV+ tumours are more likely to metastasise to distant sites, suggesting a difference in how these tumour subtypes interact with the metastatic niche. Extracellular vesicles (EVs) have emerged as important players in cell-to-cell communication and are a potential source of biomarkers for cancer diagnosis. This study aims to characterise the microRNA cargo of small EVs released by HPV+ and HPV- OPSCC cell lines. METHODS: Extracellular vesicles produced by HPV+ (SCC2 and SCC90) and HPV- (SCC72 an SCC89) OPSCC cells were characterised by tunable resistive pulse sensing (TRPS) and western blotting. RNA was extracted from EVs and analysed by small RNA sequencing. A bioinformatics approach was used to identify EV miRNA signatures associated with HPV status. RESULTS: HPV- OPSCC cells produced more EVs than HPV+ OPSCC cells. EVs were positive for the common EV markers CD63, CD9 and TSG101. Unbiased hierarchical clustering analysis of EV miRNA cargo revealed that samples clustered based on HPV status. 14 miRNA were enriched in HPV+ cell-derived EVs, whereas 19 miRNA were enriched in EVs derived from HPV- cell lines. CONCLUSIONS: Here, we identify EV miRNA signatures indicative of the HPV status of the parent cell. This may provide a platform from which to validate salivary or blood-based biomarkers with utility for early detection and stratifying risk in OPSCC patients.

Genome-Wide Analysis of Circulating Cell-Free DNA Copy Number Detects Active Melanoma and Predicts Survival.

BACKGROUND: A substantial number of melanoma patients develop local or metastatic recurrence, and early detection of these is vital to maximise benefit from new therapies such as inhibitors of BRAF and MEK, or immune checkpoints. This study explored the use of novel DNA copy-number profiles in circulating cell-free DNA (cfDNA) as a potential biomarker of active disease and survival. PATIENTS AND METHODS: Melanoma patients were recruited from oncology and dermatology clinics in Sheffield, UK, and cfDNA was isolated from stored blood plasma. Using low-coverage whole-genome sequencing, we created copy-number profiles from cfDNA from 83 melanoma patients, 44 of whom had active disease. We used scoring algorithms to summarize copy-number aberrations and investigated their utility in multivariable logistic and Cox regression analyses. RESULTS: The copy-number aberration score (CNAS) was a good discriminator of active disease (odds ratio, 3.1; 95% CI, 1.5-6.2; P = 0.002), and CNAS above or below the 75th percentile remained a significant discriminator in multivariable analysis for active disease (P = 0.019, with area under ROC curve of 0.90). Additionally, mortality was higher in those with CNASs above the 75th percentile than in those with lower scores (HR, 3.4; 95% CI, 1.5-7.9; P = 0.005), adjusting for stage of disease, disease status (active or resected), BRAF status, and cfDNA concentration. CONCLUSIONS: This study demonstrates the potential of a de novo approach utilizing copy-number profiling of cfDNA as a biomarker of active disease and survival in melanoma. Longitudinal analysis of copy-number profiles as an early marker of relapsed disease is warranted.

Wing scale ultrastructure underlying convergent and divergent iridescent colours in mimetic Heliconius butterflies.

Iridescence is an optical phenomenon whereby colour changes with the illumination and viewing angle. It can be produced by thin film interference or diffraction. Iridescent optical structures are fairly common in nature, but relatively little is known about their production or evolution. Here we describe the structures responsible for producing blue-green iridescent colour in Heliconius butterflies. Overall the wing scale structures of iridescent and non-iridescent Heliconius species are very similar, both having longitudinal ridges joined by cross-ribs. However, iridescent scales have ridges composed of layered lamellae, which act as multilayer reflectors. Differences in brightness between species can be explained by the extent of overlap of the lamellae and their curvature as well as the density of ridges on the scale. Heliconius are well known for their Müllerian mimicry. We find that iridescent structural colour is not closely matched between co-mimetic species. Differences appear less pronounced in models of Heliconius vision than models of avian vision, suggesting that they are not driven by selection to avoid heterospecific courtship by co-mimics. Ridge profiles appear to evolve relatively slowly, being similar between closely related taxa, while ridge density evolves faster and is similar between distantly related co-mimics.

Correction: Consensus Analysis of Whole Transcriptome Profiles from Two Breast Cancer Patient Cohorts Reveals Long Non-Coding RNAs Associated with Intrinsic Subtype and the Tumour Microenvironment.

[This corrects the article DOI: 10.1371/journal.pone.0163238.].