Managing the risks associated with technological disruption in the road transport system: a control structure modelling approach

Road transport is experiencing disruptive change from new first-of-a-kind technologies. While such technologies offer safety and operational benefits, they also pose new risks. It is critical to proactively identify risks during the design, development and testing of new technologies. The Systems Theoretic Accident Model and Processes (STAMP) method analyses the dynamic structure in place to manage safety risks. This study applied STAMP to develop a control structure model for emerging technologies in the Australian road transport system and identified control gaps. The control structure shows the actors responsible for managing risks associated with first-of-a-kind technologies and the existing control and feedback mechanisms. Gaps identified related to controls (e.g. legislation) and feedback mechanisms (e.g. monitoring for behavioural adaptation). The study provides an example of how STAMP can be used to identify control structure gaps requiring attention to support the safe introduction of new technologies.

Dynamic Acetabular Cup Orientation during Gait: A Study of Fast- and Slow-Walking Total Hip Replacement Patients

The dynamic orientation of total hip replacement acetabular cups during walking may vary substantially from their assumed position at surgical implantation and may vary between individuals. The scale of this effect is of interest for both pre-clinical device testing and for pre-operative surgical planning. This work aimed to evaluate (1) patient variation in dynamic cup orientation; (2) whether walking speed was a candidate proxy measure for the dynamic cup orientation; and (3) the relationships between dynamic cup orientation angles and planar pelvic angles. Pelvic movement data for patients with fast (20 patients) and slow (19 patients) self-selected walking speeds were used to calculate acetabular cup inclination and version angles through gait. For aim 1, the range and extremes of acetabular cup orientation angles were analysed for all patients. A large patient-to-patient variation was found in the ranges of both inclination angle (1° to 11°) and version angle (4° to 18°). The version angle was typically retroverted in comparison to the implantation position (greatest deviation 27°). This orientation is substantially different to the static, 0° version, simplifying assumptions in pre-clinical 'edge loading' testing. For aim 2, the cup orientation angles were compared between the fast- and slow-walking groups using statistical parametric mapping. The only significant differences observed were for cup version angle, during ~12% of the gait cycle before toe-off (p < 0.05). Therefore, self-selected walking speed, in isolation, is not a sufficient proxy measure for dynamic acetabular orientation. For aim 3, correlations were recorded between the acetabular cup orientation angles and the planar pelvic angles. The cup inclination angle during gait was strongly correlated (Spearman's coefficient -1) with pelvic obliquity alone, indicating that simple planar assessment could be used to anticipate inclination angle range. The cup version angle was correlated with both pelvic rotation and tilt (Spearman's coefficient 0.8-1), indicating that cup version cannot be predicted directly from any single pelvic movement. This complexity, along with the interaction between inclination angle and range of version angle, supports the use of computational tools to aid clinical understanding.

Multicenter Phase 1b/2a Clinical Trial of Radioprotectant BIO 300 Oral Suspension for Patients With Non-Small Cell Lung Cancer Receiving Concurrent Chemoradiotherapy

PURPOSE

Radiation therapy is part of the standard treatment regimen for non-small cell lung cancer (NSCLC). Although radiation therapy is an effective tool to manage NSCLC, it can be associated with significant dose-limiting toxicities. These toxicities can lead to treatment interruption or early termination and worsening clinical outcomes in addition to reductions in patient quality of life. Based on preclinical efficacy for radioprotection of normal tissues, we evaluated the clinical utility of BIO 300 Oral Suspension (BIO 300; synthetic genistein nanosuspension) in patients with NSCLC.

METHODS AND MATERIALS

In this multicenter, open-label, single-arm, ascending dose phase 1b/2a study, patients were enrolled with newly diagnosed stage II-IV NSCLC planned for 60 to 70/1.8-2.0 Gy radiation therapy and concurrent weekly paclitaxel/carboplatin. Oral BIO 300 (cohort 1, 500 mg/d; cohort 2, 1000 mg/d; cohort 3, 1500 mg/d) was self-administered once daily starting 2 to 7 days before initiating concurrent chemoradiotherapy and continued until the end of radiation therapy. The primary endpoint was acute dose-limiting toxicities attributable to BIO 300. Secondary outcomes included pharmacokinetics, pharmacodynamics, overall toxicity profile, quality of life, local response rate, and survival.

RESULTS

Twenty-one participants were enrolled. No dose-limiting toxicities were reported. BIO 300 dosing did not alter chemotherapy pharmacokinetics. Adverse events were not dose-dependent, and those attributable to BIO 300 (n = 11) were all mild to moderate in severity (grade 1, n = 9; grade 2, n = 2) and predominantly gastrointestinal (n = 7). A dose-dependent decrease in serum transforming growth factor β1 levels was observed across cohorts. Based on safety analysis, the maximum tolerated dose of BIO 300 was not met. Patient-reported quality of life and weight were largely stable throughout the study period. No patient had progression as their best overall response, and a 65% tumor response rate was achieved (20% complete response rate).

CONCLUSIONS

The low toxicity rates, along with the pharmacodynamic results and tumor response rates, support further investigation of BIO 300 as an effective radioprotector.

Forecasting emergent risks in advanced AI systems: an analysis of a future road transport management system

Artificial Intelligence (AI) is being increasingly implemented within road transport systems worldwide. Next generation of AI, Artificial General Intelligence (AGI) is imminent, and is anticipated to be more powerful than current AI. AGI systems will have a broad range of abilities and be able to perform multiple cognitive tasks akin to humans that will likely produce many expected benefits, but also potential risks. This study applied the EAST Broken Links approach to forecast the functioning of an AGI system tasked with managing a road transport system and identify potential risks. In total, 363 risks were identified that could have adverse impacts on the stated goals of safety, efficiency, environmental sustainability, and economic performance of the road system. Further, risks beyond the stated goals were identified; removal from human control, mismanaging public relations, and self-preservation. A diverse set of systemic controls will be required when designing, implementing, and operating future advanced technologies.Practitioner summary: This study demonstrated the utility of HFE methods for formally considering risks associated with the design, implementation, and operation of future technologies. This study has implications for AGI research, design, and development to ensure safe and ethical AGI implementation.

Effect of Tryptic Digestion on Sensitivity and Specificity in MALDI-TOF-Based Molecular Diagnostics through Machine Learning

The digestion of protein into peptide fragments reduces the size and complexity of protein molecules. Peptide fragments can be analyzed with higher sensitivity (often > 102 fold) and resolution using MALDI-TOF mass spectrometers, leading to improved pattern recognition by common machine learning algorithms. In turn, enhanced sensitivity and specificity for bacterial sorting and/or disease diagnosis may be obtained. To test this hypothesis, four exemplar case studies have been pursued in which samples are sorted into dichotomous groups by machine learning (ML) software based on MALDI-TOF spectra. Samples were analyzed in 'intact' mode in which the proteins present in the sample were not digested with protease prior to MALDI-TOF analysis and separately after the standard overnight tryptic digestion of the same samples. For each case, sensitivity (sens), specificity (spc), and the Youdin index (J) were used to assess the ML model performance. The proteolytic digestion of samples prior to MALDI-TOF analysis substantially enhanced the sensitivity and specificity of dichotomous sorting. Two exceptions were when substantial differences in chemical composition between the samples were present and, in such cases, both 'intact' and 'digested' protocols performed similarly. The results suggest proteolytic digestion prior to analysis can improve sorting in MALDI/ML-based workflows and may enable improved biomarker discovery. However, when samples are easily distinguishable protein digestion is not necessary to obtain useful diagnostic results.

Protocolized screening and detection of occult alcohol use before and after liver transplant: Lessons learned from a quality improvement initiative

INTRODUCTION

Detection of alcohol (ETOH) use with biomarkers provides an opportunity to intervene and treat patients with alcohol use disorder before and after liver transplant (LT). We describe our center's experience using urine ethyl glucuronide (EtG) and serum phosphatidylethanol (PEth) in alcohol screening protocols.

METHODS

Single-center, retrospective review of patients presenting for LT evaluation, patients waitlisted for LT for alcohol-associated liver disease (ALD), and patients who received a LT for ALD over a 12-month period, from October 1, 2019 through September 30, 2020. Patients were followed from waitlisting to LT, or for up to 12 months post-LT. We monitored protocol adherence to screening for ETOH use- defined as completion of all possible tests over the follow-up period- at the initial LT visit, while on the LT waitlist and after LT.

RESULTS

During the study period, 227 patients were evaluated for LT (median age 57 years, 58% male, 78% white, 54.2% ALD). Thirty-one patients with ALD were placed on the waitlist, and 38 patients underwent LT for ALD during this time period. Protocolized adherence to screening for alcohol use was higher for PEth for all LT evaluation patients (191 [84.1%] vs. 146 [67%] eligible patients, p < .001), in patients with ALD waitlisted for LT (22 [71%] vs. 14 (48%] eligible patients, p = .04) and after LT for ALD, 20 (33 [86.8%] vs. 20 [52.6%] eligible patients, p < .01). Few patients with a positive test in any group completed chemical dependency treatment.

CONCLUSIONS

When screening for ETOH use in pre- and post-LT patients, protocol adherence is higher using PEth compared to EtG. While protocolized biomarker screening can detect recurrent ETOH use in this population, engagement of patients into chemical dependency treatment remains challenging.

Examining factors for the adoption of silvopastoral agroforestry in the Colombian Amazon

Current land use systems in the Amazon largely consist of extensive conventional productivist livestock operations that drive deforestation. Silvopastoral systems (SPS) support a transition to low carbon production if they intensify in sympathy with the needs of biophysical and socio-economic contexts. SPS have been promoted for decades as an alternative livestock production system but widespread uptake has yet to be seen. We provide a schema of associating factors for adoption of SPS based on past literature in tropical agriculture and apply this to a bespoke survey of 172 farms in the Caquetá region of the Colombian Amazon. We find a number of factors which do not apply to this region and argue for a context specific approach. The impact of managing increased market access and opportunities for SPS producers are crucial to avoiding additional deforestation. Further understanding of the underlying antecedents of common factors, such as perceptions of silvopastoral systems, would reduce the risk of perverse policy outcomes.

Haemostatic resuscitation in practice: a descriptive analysis of blood products administered during Operation HERRICK, Afghanistan

INTRODUCTION

Life-threatening haemorrhage is the leading cause of potentially survivable injury in battlefield casualties. During Operation HERRICK (Afghanistan), mortality rates improved year on year due to a number of advances in trauma care, including haemostatic resuscitation. Blood transfusion practice has not previously been reported in detail during this period.

METHODS

A retrospective analysis of blood transfusion at the UK role 3 medical treatment facility (MTF) at Camp Bastion between March 2006 and September 2014 was performed. Data were extracted from two sources: the UK Joint Theatre Trauma Registry (JTTR) and the newly established Deployed Blood Transfusion Database (DBTD).

RESULTS

3840 casualties were transfused 72 138 units of blood and blood products. 2709 adult casualties (71%) were fully linked with JTTR data and were transfused a total of 59 842 units. Casualties received between 1 unit and 264 units of blood product with a median of 13 units per patient. Casualties wounded by explosion required almost twice the volume of blood product transfusion as those wounded by small arms fire or in a motor vehicle collision (18 units, 9 units, and 10 units, respectively). More than half of blood products were transfused within the first 2 hours following arrival at the MTF. There was a trend towards balanced resuscitation with more equal ratios of blood and blood products being used over time.

CONCLUSION

This study has defined the epidemiology of blood transfusion practice during Operation HERRICK. The DBTD is the largest combined trauma database of its kind. It will ensure that lessons learnt during this period are defined and not forgotten; it should also allow further research questions to be answered in this important area of resuscitation practice.

Dynamic finite element analysis of hip replacement edge loading: Balancing precision and run time in a challenging model

An important aspect in evaluating the resilience of hip replacement designs is testing their performance under adverse conditions that cause edge loading of the acetabular liner. The representation of edge loading conditions in finite element models is computationally challenging due to the changing contact locations, need for fine meshes, and dynamic nature of the system. In this study, a combined mesh and mass-scaling sensitivity study was performed to identify an appropriate compromise between convergence and solution time of explicit finite element analysis in investigating edge loading in hip replacement devices. The optimised model was then used to conduct a sensitivity test investigating the effect of different hip simulator features (the mass of the translating fixture and mediolateral spring damping) on the plastic strain in the acetabular liner. Finally, the effect of multiple loading cycles on the progressive accumulation of plastic strain was then also examined using the optimised model. A modelling approach was developed which provides an effective compromise between mass-scaling effects and mesh refinement for a solution time per cycle of less than 1 h. This 'Recommended Mesh' model underestimated the plastic strains by less than 10%, compared to a 'Best Estimate' model with a run time of ∼190 h. Starting with this model setup would therefore significantly reduce any new model development time while also allowing the flexibility to incorporate additional complexities as required. The polyethylene liner plastic strain was found to be sensitive to the simulator mass and damping (doubling the mass or damping had a similar magnitude effect to doubling the swing phase load) and these should ideally be described in future experimental studies. The majority of the plastic strain (99%) accumulated within the first three load cycles.

A comparison of perceived image quality between computer display monitors and augmented reality smart glasses

INTRODUCTION

Augmented-reality (AR) smart glasses provide an alternative to standard computer display monitors (CDM). AR smart glasses may provide an opportunity to improve visualisation during fluoroscopy and interventional radiology (IR) procedures when there can be difficulty in viewing intra-procedural images on a CDM. The aim of this study was to evaluate radiographer perception of image quality (IQ) when comparing CDM and AR smart glasses.

METHODS

38 radiographers attending an international congress evaluated ten fluoroscopic-guided surgery and IR images on both a CDM (1920 × 1200 pixels) and a set of Epson Moverio BT-40 AR smart glasses (1920 × 1080 pixels). Participants provided oral responses to pre-defined IQ questions generated by study researchers. Summative IQ scores for each participant/image were compared between CDM and AR smart glasses.

RESULTS

Of the 38 participants, the mean age was 39 ± 1 years. 23 (60.5%) participants required corrective glasses. In terms of generalisability, participants were from 12 different countries, the majority (n = 9, 23.7%) from the United Kingdom. For eight out of ten images, the AR smart glasses demonstrated a statistically significant increase in perceived IQ (median [IQR] 2.0 [-1.0 to 7.0] points) when compared to the CDM.

CONCLUSION

AR smart glasses appear to show improvements in perceived IQ when compared to a CDM. AR smart glasses could provide an option for improving the experiences of radiographers involved in image-guided procedures and should be subject to further clinical evaluations.

IMPLICATIONS FOR PRACTICE

Opportunities exist to improve perceived IQ for radiographers when reviewing fluoroscopy and IR images. AR smart glasses should be further evaluated as a potential opportunity to improve practice when visual attention is split between positioning equipment and image review.

Experimental characterization of a planar phase-engineered metamaterial lenslet for millimeter astronomy

To unveil presently inscrutable details of the origins of our universe imprinted in the cosmic microwave background, future experiments in the millimeter and submillimeter range are focusing on the detection of fine features, which necessitate large and sensitive detector arrays to enable multichroic mapping of the sky. Currently, various approaches for coupling light to such detectors are under investigation, namely, coherently summed hierarchical arrays, platelet horns, and antenna-coupled planar lenslets. The last option offers increased bandwidth and a simpler fabrication while maintaining the desired optical performance. In this work, the design, fabrication, and experimental characterization of a prototype planar metamaterial phase-engineered lenslet operating in W-band [75 GHz; 110 GHz] is presented. Its radiated field, initially modeled and measured on a systematics-limited optical bench, is compared against a simulated hyperhemispherical lenslet, a more established technology. It is reported here that our device reaches the cosmic microwave background (CMB) specification for the next stages of experiments, demonstrating power coupling above 95% and beam Gaussicity above 97% while maintaining ellipticity below 10% and a cross-polarization level below -21d B through its operating bandwidth. Such results underline the potential advantages our lenslet can offer as focal optics for future CMB experiments.

Resected cytokeratin-negative small cell lung carcinoma

Small cell lung carcinoma (SCLC), a malignancy of neuroendocrine origin, can show varied morphologies and patterns but is typically positive for at least one neuroendocrine marker and almost always for cytokeratins. It is essential to distinguish this tumour due to its characteristic genetic features, aggressive behaviour, propensity for metastasis and responsiveness to chemotherapy. We hereby present a rare case of a pulmonary mass that showed morphological features of an SCLC but lacked cytokeratin expression on biopsy as well as resection specimens. Various cytokeratins were tested on multiple blocks and at different laboratories. A broad differential diagnosis was considered and ruled out including small round blue cell tumours, non-SCLC and metastasis. After performing an extensive work-up to identify the origin of this tumour, it was finally diagnosed as SCLC with expression of neuroendocrine markers synaptophysin and CD56, and intracytoplasmic electron dense neurosecretory granules (250-350 nm) however lacked cytokeratin expression.

Comprehensive genomic profiling: Does timing matter?

Purpose

There is variability in utilization of Comprehensive Genomic Profiling (CGP) in most of the metastatic solid tumors (MST). We evaluated the CGP utilization patterns and its impact on outcomes at an academic tertiary center.

Patients and Methods

Institutional database was reviewed for CGP data in adult patients with MST between 01/2012 - 04/2020. Patients were categorized based on interval between CGP and metastatic diagnosis; 3 tertiles of distribution (T1-earliest to the diagnosis, T3-furthest), and pre-mets (CGP performed prior to diagnosis of metastasis). Overall survival (OS) was estimated from the time of metastatic diagnosis with left truncation at the time of CGP. Cox regression model was used to estimate the impact of timing of CGP on survival.

Results

Among 1,358 patients, 710 were female, 1,109 Caucasian, 186 Afro-Americans, and 36 Hispanic. The common histologies were lung cancer (254; 19%), colorectal cancer (203; 15%), gynecologic cancers (121; 8.9%), and pancreatic cancer (106; 7.8%). Time interval between diagnosis of metastatic disease and CGP was not statistically significantly different based on sex, race and ethnicity after adjusting for histologic diagnoses with 2 exceptions - Hispanics with lung cancer had delayed CGP compared to non-Hispanics (p =0.019) and females with pancreas cancer had delayed CGP compared to males (p =0.025). Lung cancer, gastro-esophageal cancer and gynecologic malignancies had better survival if they had CGP performed during the first tertile after metastatic diagnosis.

Conclusion

CGP utilization across cancer types was equitable irrespective of sex, race and ethnicity. Early CGP after metastatic diagnosis might have effect on treatment delivery and clinical outcomes in cancer type with more actionable targets.

Diagnostic Screening of Bovine Mastitis Using MALDI-TOF MS Direct-Spotting of Milk and Machine Learning

Novel strategies for diagnostic screening of animal and herd health are crucial to contain disease outbreaks, maintain animal health, and maximize production efficiency. Mastitis is an inflammation of the mammary gland in dairy cows, often resulting from infection from a microorganism. Mastitis outbreaks result in loss of production, degradation of milk quality, and the need to isolate and treat affected animals. In this work, we evaluate MALDI-TOF mass spectrometry as a diagnostic for the culture-less screening of mastitis state from raw milk samples collected from regional dairies. Since sample preparation requires only minutes per sample using microvolumes of reagents and no cell culture, the technique is promising for rapid sample turnaround and low-cost diagnosis. Machine learning algorithms have been used to detect patterns embedded within MALDI-TOF spectra using a training set of 226 raw milk samples. A separate scoring set of 100 raw milk samples has been used to assess the specificity (spc) and sensitivity (sens) of the approach. Of machine learning models tested, the gradient-boosted tree model gave global optimal results, with the Youden index of J = 0.7, sens = 0.89, and spc = 0.81 achieved for the given set of conditions. Random forest models also performed well, achieving J > 0.63, with sens = 0.83 and spc = 0.81. Naïve Bayes, generalized linear, fast large-margin, and deep learning models failed to produce diagnostic results that were as favorable. We conclude that MALDI-TOF MS combined with machine learning is an alternative diagnostic tool for detection of high somatic cell count (SCC) and subclinical mastitis in dairy herds.

Microplastic Pollution: Chemical Characterization and Impact on Wildlife

Microplastics are small pieces of plastic that are less than 5 mm in size and can be found in most environments, including the oceans, rivers, and air. These small plastic particles can have negative impacts on wildlife and the environment. In this review of the literature, we analyze the presence of microplastics in various species of wildlife, including fish, birds, and mammals. We describe a variety of analytical techniques, such as microscopy and spectrometry, which identify and quantify the microplastics in the samples. In addition, techniques of sample preparation are discussed. Summary results show that microplastics are present in all the wildlife species studied, with the highest concentrations often found in fish and birds. The literature suggests that microplastics are widely distributed in the environment and have the potential to affect a wide range of species. Further research is required to fully understand the impacts of microplastics on wildlife and the environment.

Diet and irritable bowel syndrome: an update from a UK consensus meeting

There has been a renewed interest in the role of dietary therapies to manage irritable bowel syndrome (IBS), with diet high on the agenda for patients. Currently, interest has focussed on the use of traditional dietary advice (TDA), a gluten-free diet (GFD) and the low FODMAP diet (LFD). A consensus meeting was held to assess the role of these dietary therapies in IBS, in Sheffield, United Kingdom.Evidence for TDA is from case control studies and clinical experience. Randomised controlled trials (RCT) have demonstrated the benefit of soluble fibre in IBS. No studies have assessed TDA in comparison to a habitual or sham diet. There have been a number of RCTs demonstrating the efficacy of a GFD at short-term follow-up, with a lack of long-term outcomes. Whilst gluten may lead to symptom generation in IBS, other components of wheat may also play an important role, with recent interest in the role of fructans, wheat germ agglutinins, as well as alpha amylase trypsin inhibitors. There is good evidence for the use of a LFD at short-term follow-up, with emerging evidence demonstrating its efficacy at long-term follow-up. There is overlap between the LFD and GFD with IBS patients self-initiating gluten or wheat reduction as part of their LFD. Currently, there is a lack of evidence to suggest superiority of one diet over another, although TDA is more acceptable to patients.In view of this evidence, our consensus group recommends that dietary therapies for IBS should be offered by dietitians who first assess dietary triggers and then tailor the intervention according to patient choice. Given the lack of dietetic services, novel approaches such as employing group clinics and online webinars may maximise capacity and accessibility for patients. Further research is also required to assess the comparative efficacy of dietary therapies to other management strategies available to manage IBS.

Isolation of Raoultella ornithinolytica in a HIV positive patient with a lung abscess

A 38 year old male HIV positive patient with a history of intravenous drug use presented with chest pains, cough, sputum and weight loss and radiology demonstrated the evolution of a right basal lung abscess. A lung biopsy sent for 16S rRNA analysis and sputum cultured about the same time demonstrated Raoultella ornithinolytica . No other causative pathogens were clearly identified. He gradually improved with a 4 week course of intravenous cefazolin. R. ornithinolytica is a rare, but recognised pathogen.

OP0223 DISTINGUISHING OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS SYNOVIUM WITH MACHINE LEARNING USING AUTOMATED CELL DENSITY AND PATHOLOGIST SCORES

Background

Joint damage in the knee can be severe in both rheumatoid arthritis (RA) and osteoarthritis (OA) such that total knee replacement (TKR) is often the only management option. Pathological assessment of the extent or type of synovial tissue inflammation from joint explants or biopsies can be useful. However, an ongoing challenge in using semi-quantitative assessments of synovitis is the disagreement between human pathologist scores of the same sample. We previously developed and validated a computer vision algorithm to automatically count each cell nucleus in an H&E-stained synovial whole slide image and yield a value of cell density, defined as mean nuclei count per mm2 of tissue1.

Objectives

We sought to develop methods to distinguish OA from RA based on machine learning analysis of histologic features on H&E-stained synovial tissue samples.

Methods

We measured 14 pathologist-scored histology features (137 RA and 152 OA patients) and computer vision quantified cell density (60 RA and 147 OA patients) in H&E stained synovial tissue samples from total knee replacement arthroplasty explants. A random forest model was trained using disease state (OA vs RA) as classifier and histology features and/or cell density as inputs, and feature importance scores for the model were calculated.

Results

Synovium from patients with RA exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, Russell bodies, binucleate plasma cells, sub-lining giant cells, synovial lining giant cells, and fibrin (all p<0.001), while synovium from patients with OA had increased mast cells and fibrosis (both p<0.001). Fourteen pathologist-scored features allowed for discrimination between RA and OA samples, producing a macro-averaged area under the receiver operating curve (AUC) of 0.85. This discriminatory ability was comparable to that of the computer vision score of cell density alone (AUC = 0.88). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (AUC = 0.91). The three most important features in this combined model were mast cells followed by cell density and fibrosis (Figure 1). AUC values for each individual feature are provided in Table 1. The optimal cell density threshold to distinguish RA from OA synovium was 3,400 cells per mm2, which yielded a sensitivity of 0.82 and specificity of 0.82.

Table 1.

Area under receiver operating characteristic curves (AUC) of the synovial features in distinguishing RA and OA patients

FeatureAUCAutomated Cell Density0.88Fibrosis0.84Mast cells0.80Lining hyperplasia0.78Lymphocytic inflammation0.69Fibrin0.68Plasma cells0.66Detritus0.64Binucleate plasma cells0.60Neutrophils0.60Synovial giant cells0.58Sub-lining giant cells0.57Russell bodies0.56Germinal centers0.51Mucoid change0.50Figure 1.

Importance of synovial features in distinguishing RA and OA synovium

Feature importance scores for supervised machine learning model including all 14 pathology scores and the computer vision-generated cell density.

Conclusion

H&E-stained images of RA and OA TKR explant synovium are distinct. We identified cell density, mast cells and fibrosis as the three most important features for making this distinction, with RA being characterized by increased cell density, low mast cells, and low fibrosis. Cell density greater than 3400 per mm2 of tissue yields a sensitivity of 0.82 and a specificity of 0.82 for distinguishing RA from OA. In the future, this can have clinical and research applications as this technique removes the requirement for subjective selection of a certain field of interest, is reproducible, and is scalable as it does not require technical expertise of a pathologist.

References

[1]Guan S, Mehta B…Orange DE. Rheumatoid Arthritis Synovial Inflammation Quantification Using Computer Vision. ACR Open Rheumatology. 2022 Jan 10;acr2.11381.

Acknowledgements

This work was supported by the C. Ronald MacKenzie Young Scientist Endowment Award, the Leon Lowenstein Foundation, and the Kellen Scholar Award supported by the Anna Marie and Stephen Kellen Foundation Total Knee Improvement Program.

Disclosure of Interests

Bella Mehta Paid instructor for: Novartis, Susan Goodman Consultant of: UCB, Grant/research support from: Novartis, Edward DiCarlo: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, and Walgreens, J. Alex Gibbons: None declared, Miguel Otero Consultant of: Regeneron Pharmaceuticals, Grant/research support from: Tissue Genesis, Laura Donlin Speakers bureau: Stryker, Consultant of: Stryker, Grant/research support from: Karius, Inc, Tania Pannellini: None declared, William Robinson: None declared, Peter Sculco Consultant of: Intellijoint Surgical, DePuy Synthes, Lima Corporate, Zimmer Biomet, and EOS Imaging, Grant/research support from: Intellijoint Surgical and Zimmer Biomet, Mark Figgie Shareholder of: HS2, Mekanika, and Wishbone, Consultant of: Lima and Wishbone, Jose Rodriguez Consultant of: ConforMIS, Medacta, Exactech, Inc, and Smith & Nephew, Grant/research support from: DePuy, Exactech, Inc, and Smith & Nephew, Jessica Kirschmann: None declared, James Thompson: None declared, David Slater: None declared, Damon Frezza: None declared, Zhenxing Xu: None declared, Fei Wang: None declared, Dana Orange: None declared

An audit of acute respiratory antibiotic prescribing in COPD patients during the COVID-19 pandemic

Introduction

Coronavirus-2 is the virus responsible for the COVID-19 pandemic. People with certain risk factors, such as having chronic obstructive pulmonary disease (COPD) may be more likely to develop complications. Research has identified that ~7% of patients with COVID-19 have a bacterial infection, however antibiotic prescribing rates have been found to vary from 38% to 72% (1,2). Primary care is estimated to make up 75% of antibiotic prescribing and was therefore a key target to evaluate whether antimicrobial stewardship principles were being followed during the COVID-19 pandemic.

Aim

To audit the adherence of antibiotic prescribing in people with COPD during the COVID-19 pandemic across a primary care network (PCN) in England against national and local guidelines.

Methods

The management of patients with COPD should follow NICE Guideline (NG) 114, NG168 and the local formulary. Three audit standards were created: 1) 100% of COPD patients should not be started on prophylactic antibiotics to reduce risk from COVID-19; 2) 100% of COPD patients should not be prescribed antibiotics for COVID-19 symptoms; 3) 90% of antibiotic prescription regimens should adhere to local and national guidelines. Prescribing data was collected from 12 practices linked to the PCN. Data of patients who had COPD, were prescribed an antibiotic, and had an indication for the antibiotic between 01/03/20 and the 30/06/20 were extracted and transferred into an anonymised spreadsheet. A total of 1088 data points were extracted. Random stratified sampling provided 300 data points for analysis, ensuring each GP surgery was represented proportionally; the required sample size to determine significance was 291. For each practice, the total number of antibiotics prescribed to COPD patients between March-June 2019 and March-June 2020 was extracted. Descriptive statistics were used to determine antibiotic prescribing adherence and overall rates of prescribing. Inferential statistics were used to compare rates of prescribing pre-vs-during the pandemic.

Results

Antibiotics were not prescribed for any patient for prophylaxis against COVID-19 (100% adherence to criteria 1). Two patients were prescribed antibiotics for ‘suspected disease caused by COVID-19’ (99.4% adherence to criteria 2). In only 28.7% of cases, the antibiotic was prescribed in line with the national and local guidelines (criteria 3). In most cases, treatment duration was the main reason for poor adherence, with longer courses of antibiotics being prescribed (7 rather than 5 days). Prescribing rates did not change significantly in 2020 compared to 2019 (1134 antibiotic prescriptions vs 1029 antibiotic prescriptions; p&gt;0.05).

Conclusion

The audit was successful in determining that the COVID-19 pandemic did not significantly affect antibiotic prescribing rates across the PCN for people with COPD. Adherence to NICE and local guidelines was low, specifically concerning the duration of antibiotic treatment. This highlights an area for improvement; to ensure healthcare professionals across the PCN prescribe in-line with antimicrobial stewardship principles. Extracted data was limited to antibiotic prescribing and could have been expanded to include steroids to provide a fuller audit of prescribing in COPD exacerbations. A re-audit may be beneficial since the publication of NG191.

References

(1) Lansbury L, Lim B, Baskaran V, Lim WS. Co-infections in people with COVID-19: a systematic review and meta-analysis. J Infect. 2020 Aug;81(2):266-275.

(2) Seaton RA, Gibbons CL, Cooper L, Malcolm W, McKinney R, Dundas S, Griffith D, Jeffreys D, Hamilton K, Choo-Kang B, Brittain S, Guthrie D, Sneddon J. Survey of antibiotic and antifungal prescribing in patients with suspected and confirmed COVID-19 in Scottish hospitals. J Infect. 2020 Dec;81(6):952-960.

The effect of an augmented reality educational tool on the motivation towards learning in pharmacy students: an evaluative survey

Introduction

Within the context of education, motivation relates to the desire students possess to engage in their learning environment. This quality is vital in determining the effort an individual expresses towards their learning and the desire they have to achieve higher academic performances (1). Educational technologies, particularly digital technologies, have long been used in post-secondary education to increase collaboration, critical thinking and motivation among students (2). The advancements in technology have led to the creation of novel augmented reality (AR) educational tools, however they have not been widely implemented or researched with the education of pharmacy students in the United Kingdom.

Aim

To identify changes of pharmacy students’ self-reported intrinsic motivation towards learning after using the ‘Pharma Compounds AR’ (PCAR) educational tool.

Methods

The PCAR tool was an image-based educational AR mobile application – it displayed 3-D models and animations of complex molecules when unique target images were scanned with the mobile’s camera. 118 stage two undergraduate Pharmacy students from a University in England were approached through cohort emails that contained a link to an online consent form and pre-intervention questionnaire. Participants were required to complete the pre-questionnaire before they received the PCAR tool for at least two months. Students were informed that they could use the tool to accommodate their learning in any way they felt appropriate. Once the intervention period ended, participants completed an online post-questionnaire. Changes in self-reported intrinsic motivation were determined with the use of adapted Intrinsic Motivation Inventory (IMI) Likert scale questions. The pre-questionnaire focused on motivation towards learning using conventional methods and their perceived usefulness, whereas the post-questionnaire focused on motivation towards learning with the PCAR tool and its perceived usefulness. Descriptive and inferential statistical analyses were conducted on the IMI adapted Likert scales.

Results

A total of 68 (57.6% rr) undergraduate Pharmacy students completed the pre-questionnaire. The majority were aged 18-21(82.4%), female (70.6%) and domestic (94.1%). The post-questionnaire was completed by 30 students (44.1% rr), mainly aged 18-21 (83.3%), female (70%), and domestic (86.7%). Participants ranked their agreement to each Likert statement from 1 (not true at all) to 7 (very true). Mean agreement motivation scores were increased after the use of the PCAR tool (pre-3.88 vs post-5.15), as were the mean agreement scores of the learning tools’ perceived usefulness (pre-4.69 vs post-5.29). Dependant T-tests performed on responses of students who completed both questionnaires revealed a significant increase in students’ mean pre- and post-intervention motivation towards learning scores (p=0.000). No significance was calculated between the mean pre-and post-agreement usefulness scores (p&gt;0.05).

Conclusion

Incorporating the PCAR tool into the education of stage two Pharmacy students significantly increased their reported motivation towards learning when compared to conventional methods, it was also reported as being a more useful learning tool. The drop in post-questionnaire responses has to be acknowledge as a limitation as well as not explicitly knowing how students used the PCAR tool in their studies. Nevertheless, the incorporation of AR into schools of Pharmacy could provide students and tutors more engaging teaching and learning experiences.

References

(1) Budiman R. Developing Learning Media Based on Augmented Reality (AR) to Improve Learning Motivation. J Educ Teach Learn. 2016 Sep;1(2):89–94. Available from: https://www.learntechlib.org/p/209026

(2) Martin F, Polly D, Coles S, Wang C. Examining higher education faculty use of current digital technologies: Importance, competence, and motivation. Int J Teach Learn High Educ. 2020;32(1):73–86.

Patient perceptions of clinical pharmacists in general practice

Introduction

As a result of changes in the demands and pressures on the NHS, the role of the pharmacist has advanced from purely dispensing and compounding medicines to a more clinical and patient-centred approach to care (1). Since 2015, NHS England set a target of recruiting practice-based pharmacists into 20% of practices by 2020-2021 as a way of reducing these pressures (2). Conducting evaluations of clinical pharmacists in individual practices is essential for role integration and evolution.

Aim

To explore patient perceptions of clinical pharmacists across three general practices.

Methods

A paper-based questionnaire consisting of open and closed questions was used to gather patient perceptions on the role of a clinical pharmacist and their consultation experiences. Participants included patients over the age of 18 who had attended a face-to-face appointment with a clinical pharmacist from one of three general practice surgeries in England between November and December 2019. The clinical pharmacists were used as a gateway to recruit participants; post-consultation, the pharmacist asked patients if they would complete a questionnaire. Patients were provided with an information sheet and consent form prior to completion of the questionnaire. The questionnaire was anonymous. Data were analysed using descriptive statistics and content analysis.

Results

A total of 39 participants completed the questionnaire. Most participants were elderly (28%) and female (64%). The primary reason for the consultations was due to an acute illness (79%), and the most common outcome was the supply of a prescription (83%). Patients were predominantly unfamiliar with the role of a clinical pharmacist (56%) and 31% of patients reportedly thought their appointment had been with a doctor. All patients were positive about their experience and reported they would “be more than happy to see a pharmacist in the future” and that the role was “a very necessary addition to the practice”. All patients reported that their consultation was the same (51%) or better than they have had with a doctor (49%). Patients commented on the pharmacists’ consultation skills, making statements such as [they] “listened to me”, “asked me questions”, “were really good at explaining” and “spoke in a way I understood”. Clinical pharmacists were reported as being “very professional” and knowledgeable as “[they] knew more about my medication [than the doctor] and prescribed me something to help”. Patients reported that they would recommend the clinical pharmacist to their family and friends when seeking an appointment.

Conclusion

This research highlights patient acceptance towards consultations with a clinical pharmacist and reinforces the competence of pharmacists to undertake this role. A key finding related to the effective consultation skills of the pharmacists and involving the patients in their care. The number of patients who participated limits the generalisability of the findings, and the patient responses may have been a reaction to the individual clinical pharmacists rather than their thoughts on the role overall. Increased publicity and patient education of the role of a clinical pharmacist may promote a greater integration into the multidisciplinary team.

References

(1) Robertson R, Wenzel L, Thompson J, Charles A. Understanding NHS financial pressures. How are they affecting patient care. 2017. The Kings Fund. https://www.kingsfund.org.uk/sites/default/files/field/field_publication_file/Understanding%20NHS%20financial%20pressures%20-%20full%20report.pdf

(2) NHS England 2016. General Practice Forward View. https://www.england.nhs.uk/wp-content/uploads/2016/04/gpfv.pdf

712 EVALUATING AN ‘ACUTE FRAILTY TEAM’ MODEL OF CARE IN IMPROVING OUTCOMES FOR PATIENTS WITH FRAILTY ACUTELY ADMITTED TO HOSPITAL

Introduction

In frailty, Comprehensive geriatric assessment (CGA) has benefit in improving patient outcomes, including hospital readmissions and institutionalisation. We looked to evaluate the effectiveness of our newly initiated multi-disciplinary, acute frailty team (AFT) in improving acute care. This team works on the Acute Medical Unit (AMU), delivering early CGA alongside the existing acute medical care.

Methods

The AFT initially targeted identification of frailty using the Rockwood clinical frailty score (CFS) through local quality improvement work. A standard operating procedure, encompassing CGA for all patients with frailty (define as a CFS 5 to 8 or, 4 with a frailty syndrome) was introduced. This assessment was additional to usual acute medical care. The impact was measured by retrospective case note review of 100 AMU admissions with frailty prior to the team being in post (Jan-March 2020) with a subsequent 100 patients seen by the AFT (March–April 2021). The 2 groups were matched for age, gender, frailty scores and pre-admission residence. These 2 cohorts were compared against key performance indices.

Results

The mean age of patients in the Pre and post AFT cohorts were 85 years and 84 years respectively with an average CFS of 6. The identification and documentation of frailty improved in the AFT intervention cohort from 31% to 100% and screening for delirium with 4AT improved from 27% to 91%. The number of patients in the AFT cohort discharged directly from AMU increased from 5% to 14% with the average length of in-patient stay reducing from 10.2 days to 7.8 days. Thirty day remission fell from 23% to 16% in the AFT cohort, and the number of patients discharge to new 24 hour care declined from 21% to 9%.

Conclusion

Our AFT alongside existing acute medical care improved outcomes including, frailty identification, delirium screening, length of stay, re-admissions and institutionalisation.

The advanced practitioners' perspective. Exploring the decision-making process between musculoskeletal advanced practitioners and their patients: An interpretive phenomenological study

INTRODUCTION

Advanced practice roles for allied health professionals continue to expand and provide key services within pathways of care for patients with musculoskeletal conditions. Despite the extensive utilisation of these roles and previously reported high patient satisfaction, little is understood about how these practitioners interact with their patients and the factors that influence decision-making conversations.

STUDY

A qualitative study utilised Interpretive Phenomenological Analysis (IPA) to explore the decision-making process occurring between Advanced Practitioners (APs) and their patients in a musculoskeletal service. AP data were collected through focus groups and analysed using IPA methodology.

CONCLUSIONS

Advanced practice decision-making is a complex process and APs exhibit a range of styles, from paternalistic to shared decision-making. APs may have a personal preference, but exhibit the ability to flex between styles in consultations. Multiple themes emerged from the data that influenced the decision-making process, including AP staff understanding the importance of patient expectations and the complex factors that influence patient interactions. It is important that clinicians have an awareness of the multiple factors that contribute to the decision-making process.

Impingement in total hip arthroplasty: A geometric model

Total Hip Arthroplasty (THA) is one of the most common and successful surgical interventions. The survivorship at 10 years for the most commonly used systems is over 95%. However, the incidence of revision is usually much higher in the 0-1 year time period following the intervention. The most common reason for revision in this early time period is dislocation and subluxation, which may be defined as complete or permanent, and partial or temporary loss of contact between the bearing surfaces respectively. This study comprises the development of a geometric model of bone and an in situ total hip replacement, to predict the occurrence and location of bone and component impingement for a wide range of acetabular cup positions and for a series of frequently practiced activities of daily living. The model developed predicts that anterior-superior component impingement is associated with activities that result in posterior dislocation. The incidence may be reduced by increased cup anteversion and inclination. Posterior-inferior component impingement is associated with anterior dislocation activities. Its incidence may be reduced by decreased cup anteversion and inclination. A component impingement-free range was identified, running from when the cup was positioned with 45° inclination and 25° anteversion to 70° inclination and 15°-20° anteversion.

Temporal trends of perfluoroalkyl substances in an Australian wastewater treatment plant: A ten-year retrospective investigation

Per- and poly-fluoroalkyl substances (PFAS) are a problematic group of chemicals used in various industrial and household products. They have been extensively detected in wastewater as a result of day-to-day product usage. Due to concerns about their safety, voluntary and regulatory action to limit the manufacture and use of some individual PFAS has occurred since the year 2000. The impact that this intervention has had on the use and potential exposure of Australians has not been measured. Wastewater serves as a powerful tool to assess the chemical use or consumption patterns of a population over time. We accessed a ten-year wastewater archiving program to conduct a temporal analysis of PFAS trends in an urban Australian population between the years 2010 and 2020. Results showed a decline in the concentrations for most PFAS, and a change in the PFAS profile from perfluorosulfonic acids and long-chain perfluorocarboxylic acids, to the short-chain perfluorocarboxylic acids and PFOS-replacement degradation products such as 5:3 FTCA. Intermittent pulses of PFAS that were significantly higher than 'background' levels (i.e., representing the PFAS input from primarily households) were observed, suggesting continuing industrial PFAS input within the wastewater catchment. This study highlights the long-term consequences of the diffuse use of persistent chemicals in products, and their ability to continue to enter the wastewater stream for decades.

The impact of stem fixation method on Vancouver Type B1 periprosthetic femoral fracture management

INTRODUCTION

Our understanding of the impact of the stem fixation method in total hip arthroplasty (THA) on the subsequent management of periprosthetic femoral fractures (PFF) is still limited. This study aimed to investigate and quantify the effect of the stem fixation method, i.e., cemented vs. uncemented THA, on the management of Vancouver Type B1 periprosthetic femoral fractures with the same plate.

METHODS

Eight laboratory models of synthetic femora were divided into two groups and implanted with either a cemented or uncemented hip prosthesis. The overall stiffness and strain distribution were measured under an anatomical one-legged stance. All eight specimens underwent an osteotomy to simulate Vancouver type B1 PFF's. Fractures were then fixed using the same extramedullary plate and screws. The same measurements and fracture movement were taken under the same loading conditions.

RESULTS

Highlighted that the uncemented THA and PFF fixation constructs had a lower overall stiffness. Subsequently, the mechanical strain on the fracture plate for the uncemented construct was higher compared to the cemented constructs.

CONCLUSION

PFF fixation of a Vancouver type B1 fracture using a plate may have a higher risk of failure in uncemented THAs.

Site Readiness Framework to Improve Health System Preparedness for a Potential New Alzheimer’s Disease Treatment Paradigm

New therapies that address the underlying pathophysiology of Alzheimer’s Disease (AD), coupled with the growth of the AD population, will transform the AD care pathway and present significant challenges to health systems. We explored real-world challenges health systems may face in delivering potential new AD therapies with diverse stakeholders. Key challenges in care included integrating primary care providers into assessment and management, availability of memory care specialists, understanding payment and coverage issues and training mid-level providers to help coordinate care and serve as a shared resource across the system. This input informed a novel Site Readiness Framework for AD, comprising self-assessment exercises to identify health system capabilities and gaps and a framework of core strategies and responsive tools to help prepare to integrate new AD therapies. These resources may help health systems improve readiness to modify care pathways to integrate new therapies for AD.

Differences between two sequential uncemented stem sizes in total hip arthroplasty: A comparative biomechanical study and potential clinical implications

Background: Early failure of uncemented femoral stems associated with incorrect sizing is a known postoperative complication. Surgeons are often faced with the question of whether an uncemented stem of adequate stability or a larger-sized stem should be implanted, especially when the proximal femoral cancellous bone is adequate. The biomechanical effect of sub-optimal stem sizing in the femur remains unclear. This study investigated the mechanical behaviour of two sequential sized uncemented stems of the same type. Methods: Six laboratory models of synthetic non-osteoporotic femora were randomly divided into two groups and implanted with either a nominal or oversized uncemented hydroxyapatite-coated nonporous titanium collarless stem. Stiffness, uniaxial strain, and pattern of strain distribution were measured under an anatomical one-legged stance. Results: Oversized stems demonstrated a higher overall stiffness compared to nominal; however, this was not statistically significant. The nominal stem showed a higher strain in the neck and the proximal medial diaphyseal region. The oversized stem showed higher strains in the distal region around the implant tip. Conclusion: Opting to use a larger stem may potentially increase primary stability, thus allowing safer early mobility. However, higher stiffness may lead to stress shielding, bone loss, and thigh pain in the long term. In addition, strains in the diaphysis and the tip of the stem may predispose to periprosthetic fractures, especially in osteoporotic bones, making this a relatable aspect for users and biomechanical loading. Given the wide range of complex factors that need to be considered when choosing stem size in uncemented THA surgery, this study’s results should be interpreted cautiously.

Surprising neutral effect of shorter staple cartridges in laparoscopic sleeve gastrectomy

BACKGROUND

Consensus agreements regarding laparoscopic sleeve gastrectomy (LSG) advise against using staple loads less than 1.5 mm in closed staple height. However, few data exist to support this recommendation. We hypothesized that using staples with a shorter closed height would actually decrease incidence of intraoperative and postoperative bleeding during LSG, while not increasing the incidence of leak.

METHODS

All LSG cases for a single institution from 1/1/2014 to 12/31/2019 were exported for analysis. Two cohorts were established: 1. 'Green/Blue' group was cases in which no white cartridges were used and 2. 'White' group was cases in which any white cartridges were used. Demographic variables, procedural characteristics, hospital length of stay, and postoperative outcomes were compared between groups.

RESULTS

The study populations included 1710 patients, 974 in the green/blue group and 736 in the white cartridge group. There were no significant differences in postoperative leak, bleed, stricture, readmission, or death while using white staple loads as compared with the standard combination of blue and green loads.

CONCLUSION

Using staples with a shorter closed height during LSG did not impact the postoperative bleeding or leak rate. The impact from selection of shorter staples to achieve more tissue compression may be limited.

902 Safe Elective & Emergency Surgery During the COVID-19 Crisis: Experience of a Large Tertiary Centre During the First Wave of the Pandemic

Aim

In addition to a reduction in elective surgery, the COVID-19 pandemic has been associated with concerning rates of post-operative mortality in COVID-19 patients highlighting the threat of nosocomial transmission. Relocation of elective patients into a protected cold wing of a tertiary centre, vigilant testing and staff test, and trace were implemented to address these issues.

Method

Retrospective analysis of 5069 consecutive patients who underwent procedures in theatre from 11/03/20 – 08/09/20 was performed. Comparison of numbers of procedures was compared with the same study dates in 2019. Detailed analysis of nosocomial transmission of COVID-19 and mortality was performed using patient notes and death certificates.

Results

5854 procedures were performed in 2020 compared with 13219 in 2019, representing a reduction of 55.7%. The overall mortality in 2020 was 2.7% (135/5069). COVID-19 negative mortality was 2.36% (119/5033). 74 patients tested positive for COVID-19 at any time (1.3%); mortality amongst patients who tested positive seven days pre- to 30 days post-procedure was 5.4% (4/74). Nosocomial transmission rate was 0.27% in elective admissions (10/3773) and 0.97% in acute admissions (20/2052).

Conclusions

The first wave of the pandemic has predictably caused a significant reduction in elective activity. Our hospital infection prevention measures have kept nosocomial transmission rates low, particularly for elective admissions. We have observed lower rates of post-operative mortality in COVID-19 patients than published in other centres. Continuation of surgical services is important for patient outcomes, and essential for training the surgeons of tomorrow.

Endocutter Staple Height Auto-adjusts to Tissue Thickness

BACKGROUND

Surgeon choice of the appropriate staple height has been cited as a factor in the mechanical integrity of a staple line. However, tissue measured at the industry standard 8 g/mm² is usually thicker than the formed staple height of the staples that hold it together. This means that the pressure that the staples apply must be greater than 8g/mm². Additionally, formed staple heights in tissue may be different than formed staple heights of the same cartridge type when fired without tissue. This means that there is likely a compressive limit to the individual staples deployed by the stapling system. The purpose of this study is to establish the degree to which staple heights of endocutter staples auto-adjust to tissue and the compressive limit to tissue that this infers.

MATERIALS AND METHODS

Excised gastric remnants from laparoscopic sleeve gastrectomy were measured for tissue thickness at different external pressures. An optimized experimental staple line was then created in parallel to the clinical staple line. The doubly-stapled gastric sliver then underwent computed tomography with solid modeling software to measure staple heights.

RESULTS

Staple heights fired in gastric tissue were significantly different than industry labelled and control staple heights. Clinical staple heights were significantly shorter than measured tissue thickness at 8 g/mm². Staple height more closely approximated tissue thickness under 15 g/mm² of pressure, rather than the 8 g/mm² loading pressure used by industry for tissue thickness range labelling.

CONCLUSIONS

Staples deployed in human gastric tissue are taller than commercial labelling. The closed staple height corresponds to tissue thickness under 15g/mm² of pressure, not the labelled staple height. These results demonstrate that staple heights from modern endocutter staplers adjust to tissue, approximating a maximum compressive force just above 15g/mm².

The effects of anaesthetics and sedatives on brain inflammation

Microglia are involved in many dynamic processes in the central nervous system (CNS) including the development of inflammatory processes and neuromodulation. Several sedative, analgesic or anaesthetic drugs, such as opioids, ∝2-adrenergic agonists, ketamine, benzodiazepines and propofol can cause both neuroprotective and harmful effects on the brain. The purpose of this review is to present the main findings on the use of these drugs and the mechanisms involved in microglial activation. Alpha 2-adrenergic agonists, propofol and benzodiazepines have several pro- or anti-inflammatory effects on microglia. Long-term use of benzodiazepines and propofol causes neuroapoptotic effects and α2-adrenergic agonists may attenuate these effects. Conversely, morphine and fentanyl may have proinflammatory effects, causing behavioural changes in patients and changes in cell viability in vitro. Conversely, chronic administration of morphine induces CCL5 chemokine expression in microglial cells that promotes their survival.

UV-C LED Irradiation Reduces Salmonella on Chicken and Food Contact Surfaces

Ultraviolet (UV-C) light-emitting diode (LED) light at a wavelength of 250–280 nm was used to disinfect skinless chicken breast (CB), stainless steel (SS) and high-density polyethylene (HD) inoculated with Salmonella enterica. Irradiances of 2 mW/cm² (50%) or 4 mW/cm² (100%) were used to treat samples at different exposure times. Chicken samples had the lowest Salmonella reduction with 1.02 and 1.78 Log CFU/cm² (p ≤ 0.05) after 60 and 900 s, respectively at 50% irradiance. Higher reductions on CB were obtained with 100% illumination after 900 s (>3.0 Log CFU/cm²). Salmonella on SS was reduced by 1.97 and 3.48 Log CFU/cm² after 60 s of treatment with 50% and 100% irradiance, respectively. HD showed a lower decrease of Salmonella, but still statistically significant (p ≤ 0.05), with 1.25 and 1.77 Log CFU/cm² destruction for 50 and 100% irradiance after 60 s, respectively. Longer exposure times of HD to UV-C yielded up to 99.999% (5.0 Log CFU/cm²) reduction of Salmonella with both irradiance levels. While UV-C LED treatment was found effective to control Salmonella on chicken and food contact surfaces, we propose three mechanisms contributing to reduced efficacy of disinfection: bacterial aggregation, harboring in food and work surface pores and light absorption by fluids associated with CB.