Animal factors that affect enteric methane production measured using the GreenFeed monitoring system in grazing dairy cows

Similar to all dairy systems internationally, pasture-based dairy systems are under increasing pressure to reduce their greenhouse gas (GHG) emissions. Ireland and New Zealand are 2 countries operating predominantly pasture-based dairy production systems where enteric CH4 contributes 23% and 36% of total national emissions, respectively. Ireland currently has a national commitment to reduce 51% of total GHG emissions by 2030 and 25% from agriculture by 2030, as well as striving to achieve climate neutrality by 2050. New Zealand's national commitment is to reduce 10% of methane emissions by 2030 and between 24% and 47% reduction in methane emissions by 2050. To achieve these reductions, factors that affect enteric methane (CH4) production in a pasture-based system need to be investigated. The objective of this study was to assess the relationship between enteric CH4 and other animal traits (feed intake, metabolic liveweight, energy corrected milk yield, milk urea concentration, and body condition score [BCS]) in a grazing dairy system. Enteric CH4 emissions were measured on 45 late lactation (213.8 ± 29 d after calving) grazing Holstein-Friesian and Holstein-Friesian × Jersey crossbred cows (lactation number 3.01 ± 1.65, 538.64 ± 59.37 kg live weight, and 3.14 ± 0.26 BCS) using GreenFeed monitoring equipment for 10 wk. There was a training period for the cows to use the GreenFeed of 3 wk before the 10-wk study period. The average enteric CH4 produced in the study was 352 g ± 45.7 g per day with an animal to animal coefficient of variation of 13%. Dry matter intake averaged 16.6 kg ± 2.23 kg per day, while milk solids (fat plus protein) averaged 1.62 kg ± 0.29 kg per day. A multiple linear regression model indicated that each one unit increase in energy corrected milk yield, metabolic liveweight and milk urea concentration, resulted in an increase in enteric CH4 production per day by 3.9, 1.74, and 1.38 g, respectively. Although each one unit increase in BCS resulted in a decrease in 39.03 g CH4 produced per day. When combined, these factors explained 47% of the variation in CH4 production, indicating that there is a large proportion of variation not included in the model. The repeatability of the CH4 measurements was 0.66 indicating that cows are relatively consistently exhibiting the same level of CH4 throughout the study. Therefore, enteric CH4 production is suitable for phenotyping.

Dialysis disequilibrium syndrome in neurosurgery: literature review and illustrative case example

INTRODUCTION

The dialysis disequilibrium syndrome (DDS) is a complication in those undergoing dialysis for chronic kidney disease (CKD) or acute kidney injury (AKI), characterized by nonspecific symptoms that may progress to coma and death secondary to cerebral edema. This syndrome is associated with rapid change in electrolytes during dialysis with changes in intracranial pressure (ICP) and may have a higher incidence in the elderly neurosurgical patient population.

METHODS

Literature review and illustrative case example.

RESULTS

A 62-year-old female presented with acute mental status change during hemodialysis (HD), with a history of a nonsurgical acute subdural hematoma (SDH) 10 days prior. Imaging showed a conversion of the acute SDH to chronic SDH of 12.2 mm in size with a 14.1 midline shift, for which she underwent a hemicraniectomy with SDH evacuation, with a gradual return to baseline. The literature review identified 5 publications meeting the inclusion criteria. Major theories of DDS include a reverse urea effect, intracerebral acidosis, idiogenic osmoles, and local inflammation. This complication may occur more frequently in the elderly neurosurgical patient population, likely due to age-related comorbidities, preexisting neurological insult, and increased permeability of the blood-brain barrier (BBB), leading to cerebral edema.

CONCLUSION

DDS is a rare and potentially fatal complication of HD that may have a higher incidence in the elderly neurosurgical patient population, yet remains to be fully understood. Further study is recommended to characterize the pathophysiological mechanism and incidence of DDS in neurosurgical patients.

The Association of Surgeons in Training (ASiT) Consensus Statement on Major Trauma Training in the UK

INTRODUCTION

Since the establishment of the Major Trauma Networks in 2012, it is estimated that an extra 1,600 lives have been saved across England. Although the delivery of trauma care has improved significantly, the provision of trauma training has not and remains fragmented. The Association of Surgeons in Training (ASiT), an independent organisation run by trainees, is dedicated to excellence in surgical training within the United Kingdom (UK) and Republic of Ireland (ROI). The aim of this study was to develop a consensus statement representing the views of the ASiT on the future of trauma surgery training.

METHODS

A modified nominal group technique was used in five stages: 1, scoping exercise; 2, virtual consultation; 3, nominal group consensus meeting; 4, virtual feedback from stakeholders; and 5, virtual confirmation by the ASiT Council. The design and reporting of the consensus followed best practice methodology for consensus research.

RESULTS

Overall, 62 participants gave 90 statements across stages 1-3. Eleven key themes were identified, all of which met the consensus of the ASiT Council. The key findings were widespread support for increased exposure to trauma for medical students and early surgical trainees as well as an increased use of simulation methods and improved focus on non-technical skills within trauma surgery.

CONCLUSIONS

This study sets out the position of the ASiT on the future of trauma surgery training and how training in major trauma surgery in the UK and ROI could be improved.

Measures of performance and proficiency in robotic assisted surgery: a systematic review

Robotic assisted surgery (RAS) has seen a global rise in adoption. Despite this, there is not a standardised training curricula nor a standardised measure of performance. We performed a systematic review across the surgical specialties in RAS and evaluated tools used to assess surgeons' technical performance. Using the PRISMA 2020 guidelines, Pubmed, Embase and the Cochrane Library were searched systematically for full texts published on or after January 2020-January 2022. Observational studies and RCTs were included; review articles and systematic reviews were excluded. The papers' quality and bias score were assessed using the Newcastle Ottawa Score for the observational studies and Cochrane Risk Tool for the RCTs. The initial search yielded 1189 papers of which 72 fit the eligibility criteria. 27 unique performance metrics were identified. Global assessments were the most common tool of assessment (n = 13); the most used was GEARS (Global Evaluative Assessment of Robotic Skills). 11 metrics (42%) were objective tools of performance. Automated performance metrics (APMs) were the most widely used objective metrics whilst the remaining (n = 15, 58%) were subjective. The results demonstrate variation in tools used to assess technical performance in RAS. A large proportion of the metrics are subjective measures which increases the risk of bias amongst users. A standardised objective metric which measures all domains of technical performance from global to cognitive is required. The metric should be applicable to all RAS procedures and easily implementable. Automated performance metrics (APMs) have demonstrated promise in their wide use of accurate measures.

Evaluation of Managing Cancer and Living Meaningfully (CALM) in people with advanced non-small cell lung cancer treated with immunotherapies or targeted therapies: protocol for a single-arm, mixed-methods pilot study

INTRODUCTION

People with advanced non-small cell lung cancer (NSCLC) treated with immunotherapies (IT) or targeted therapies (TT) may have improved outcomes in a subset of people who respond, raising unique psychological concerns requiring specific attention. These include the need for people with prolonged survival to reframe their life plans and tolerate uncertainty related to treatment duration and prognosis. A brief intervention for people with advanced cancer, Managing Cancer and Living Meaningfully (CALM), could help people treated with IT or TT address these concerns. However, CALM has not been specifically evaluated in this population. This study aims to evaluate the acceptability and feasibility of CALM in people with advanced NSCLC treated with IT or TT and obtain preliminary evidence regarding its effectiveness in this population.

METHODS AND ANALYSIS

Twenty people with advanced NSCLC treated with IT or TT will be recruited from Peter MacCallum Cancer Centre, Melbourne, Australia. Participants will complete three to six sessions of CALM delivered over 3-6 months. A prospective, single-arm, mixed-methods pilot study will be conducted. Participants will complete outcome measures at baseline, post-intervention, 3 months and 6 months, including Patient Health Questionnaire, Death and Dying Distress Scale, Functional Assessment of Cancer Therapy General and Clinician Evaluation Questionnaire. The acceptability of CALM will be assessed using patient experiences surveys and qualitative interviews. Feasibility will be assessed by analysis of recruitment rates, treatment adherence and intervention delivery time.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the Peter MacCallum Cancer Centre Human Research Ethics Committee (HREC/82047/PMCC). Participants with cancer will complete a signed consent form prior to participation, and carers and therapists will complete verbal consent. Results will be made available to funders, broader clinicians and researchers through conference presentations and publications. If CALM is found to be acceptable in this cohort, this will inform a potential phase 3 trial.

Evaluation of a 30-day-mortality risk calculator for patients undergoing surgical fixation of fragility hip fractures

INTRODUCTION

Hip fractures often occur in medically complex patients and can be associated with high perioperative mortality. Mortality risk assessment tools that are specific to hip fracture patients have not been extensively studied. The objective of this study is to evaluate a recently published 30-day mortality risk calculator (Hip Fracture Estimator of Mortality Amsterdam [HEMA]) in a group of patients treated at a university health system.

MATERIALS & METHODS

625 patients treated surgically for hip fractures between 2015 and 2020 at our institution were retrospectively reviewed. Patients younger than age 65, periprosthetic fractures, revision procedures, and fractures treated non-operatively were excluded. Univariate and multivariate analyses were used to determine significant relationships between variables and 30-day mortality after surgery. Additional patient-specific risk factors not included in the original risk calculator were also evaluated.

RESULTS

The observed 30-day mortality was 5.6%. HEMA score was significantly associated with 30-mortality, though our cohort had significantly lower mortality rates in high-risk patients than expected based on the HEMA tool. In analyzing patient characteristics not included in HEMA score, history of dementia and elevated troponin were significantly associated with 30-day mortality.

DISCUSSION

The HEMA score reliably stratifies risk for 30-day mortality after hip fracture, though overestimates mortality in high-risk patients treated at a tertiary care center with a multidisciplinary team. The HEMA score may be enhanced by considering additional variables, including troponin level and history of dementia.

LEVEL OF EVIDENCE

IV.

Dysregulation of ribosome-associated quality control elicits cognitive disorders via overaccumulation of TTC3

Ribosome-associated quality control (RQC) pathway is responsible for degradation of nascent polypeptides in aberrantly stalled ribosomes, and its defects may lead to neurological diseases. However, the underlying molecular mechanism of how RQC dysfunction elicits neurological disorders remains poorly understood. Here we revealed that neurons with knockout (KO) of ubiquitin ligase LTN1, a key gene in the RQC pathway, show developmental defects in neurons via upregulation of TTC3 and UFMylation signaling proteins. The abnormally enhanced TTC3 protein in Ltn1 KO neurons reduced further accumulation of translationally arrested products by preventing translation initiation of selective genes. However, the overaccumulated TTC3 protein in turn caused dendritic abnormalities and reduced surface-localized GABA_A receptors during neuronal development. Ltn1 KO mice showed behavioral deficits associated with cognitive disorders, a subset of which were restored by TTC3 knockdown in medial prefrontal cortex. Together, the overactivated cellular compensatory mechanism against defective RQC through TTC3 overaccumulation induced synaptic and cognitive deficits. More broadly, these findings represent a novel cellular mechanism underlying neuronal dysfunctions triggered by exaggerated cellular stress response to accumulated abnormal translation products in neurons.

Hypotension requiring vasopressor treatment and increased cardiac complications in elderly spinal cord injury patients: a prospective TRACK-SCI registry study

OBJECTIVE

Increasing life expectancy has led to an older population. In this study, the authors analyzed complications and outcomes in elderly patients following spinal cord injury (SCI) using the established multi-institutional prospective study Transforming Research and Clinical Knowledge in SCI (TRACK-SCI) database collected in the Department of Neurosurgical Surgery at the University of California, San Francisco.

METHODS

TRACK-SCI was queried for elderly individuals (≥ 65 years of age) with traumatic SCI from 2015 to 2019. Primary outcomes of interest included total hospital length of stay, perioperative complications, postoperative complications, and in-hospital mortality. Secondary outcomes included disposition location, and neurological improvement based on the American Spinal Injury Association Impairment Scale (AIS) grade at discharge. Descriptive analysis, Fisher's exact test, univariate analysis, and multivariable regression analysis were performed.

RESULTS

The study cohort consisted of 40 elderly patients. The in-hospital mortality rate was 10%. Every patient in this cohort experienced at least 1 complication, with a mean of 6.6 separate complications (median 6, mode 4). The most common complication categories were cardiovascular, with a mean of 1.6 complications (median 1, mode 1), and pulmonary, with a mean of 1.3 (median 1, mode 0) complications, with 35 patients (87.5%) having at least 1 cardiovascular complication and 25 (62.5%) having at least 1 pulmonary complication. Overall, 32 patients (80%) required vasopressor treatment for mean arterial pressure (MAP) maintenance goals. The use of norepinephrine correlated with increased cardiovascular complications. Only 3 patients (7.5%) of the total cohort had an improved AIS grade compared with their acute level at admission.

CONCLUSIONS

Given the increased frequency of cardiovascular complications associated with vasopressor use in elderly SCI patients, caution is warranted when targeting MAP goals in these patients. A downward adjustment of blood pressure maintenance goals and prophylactic cardiology consultation to select the most appropriate vasopressor agent may be advisable for SCI patients ≥ 65 years of age.

Impact of COVID-19 pandemic on emergency department patient volume and flow: Two countries, two hospitals

OBJECTIVES

COVID-19 greatly disrupted the provision of emergency care across the globe. ED service delivery was urgently redesigned as human and material resources were mobilised, and patients with respiratory symptoms were isolated. This study aimed to compare ED patient volume and flow metrics before and during the COVID-19 pandemic.

METHODS

An observational study was conducted in two large urban EDs in Brisbane, Australia and Seoul, Republic of Korea. Patient volume and flow were quantified using ED presentation numbers and service times, respectively. Daily case numbers, waiting, treatment and admission delay times were compared between 2019 and 2020/2021 using time series plots. Outcomes were further classified by triage category and age group. Trends were examined alongside a timeline of health service and government policies.

RESULTS

There were reductions in daily presentations for the least urgent triage categories during the early phase of the pandemic. The caseloads for the most urgent triage categories were unaffected. The trends were similar in both EDs. A reduction in waiting and admission delay times but not treatment times coincided with reduced presentations in Brisbane. This pattern gradually reversed as presentations returned to baseline. In Seoul, admission delay times returned to pre-pandemic levels despite a persistent reduction in presentation numbers.

CONCLUSIONS

Total daily presentations varied considerably according to government mandated social restrictions and testing requirements in both EDs. The reductions in waiting and admission delay times corresponded with improvements in hospital capacity.

Effect of heat shield locations on rework-induced thermal management in ball grid array solder joint

This study investigated the effectiveness of heat shield placement locations during the rework process to avoid thermal and mechanical damage to adjacent ball grid array components and their solder joints on double-sided printed circuit board assembly. Three types of heat shield placement locations were used: sample X, individual heat shield placement on adjacent components of the rework location; sample Y, a U-shaped, and sample Z, a square-shaped heat shield placed respectively at the heat source location. The dye and pull test results, infrared thermography, and temperature measurements were analysed to understand the relationship between the location of the heat shield and solder joint damage during rework. Heat shield placement at the heat source location on the reworked component can reduce the peak temperatures on the adjacent rework component locations by up to 8.18%. The peak temperatures of the centre and corner of the BGA component can be maintained below 195 °C and 210 °C, respectively to improve the adjacent rework component locations' solder joint quality by reducing solder joint damage by more than 50% solder cracks. This is useful for thermal management during rework involving high-density ball grid array component placements on double-sided printed circuit board assembly.

Taking the EZ way: Targeting enhancer of zeste homolog 2 in B-cell lymphomas

Enhancer of zeste homolog 2 (EZH2) is an epigenetic regulator that controls the normal biology of germinal B cells. Overexpression or mutation of EZH2 is associated with malignant transformation in a number of B-cell malignancies; thus, EZH2 inhibitors are an attractive therapeutic option for these targets. Several EZH2 inhibitors have entered clinical trials, but there remains an important question as to how EZH2 inhibitor mechanism of action differs in patients with mutant and wild-type EZH2. This review discusses the EZH2-driven mechanisms that lead to the development of B-cell lymphomas and act as therapeutic targets. Another key area of investigation is whether EZH2 inhibitors will work synergistically with existing immunomodulatory drugs and chemotherapy regimens. In summary, EZH2 inhibitors show potential as treatment for a range of B-cell lymphomas, and numerous clinical evaluations are currently underway.

A meta-analysis of laparoscopic versus ultrasound-guided transversus abdominis plane block in laparoscopic colorectal surgery

BACKGROUND

Enhanced recovery programmes in laparoscopic colorectal surgery (LCS) employ combined approaches to achieve postoperative analgesia. Transversus abdominis plane (TAP) block is a locoregional anaesthetic technique that may reduce postoperative pain.

AIMS

To perform a systematic review and meta-analysis to compare the effectiveness of laparoscopic- versus ultrasound-guided TAP block in LCS.

METHODS

Databases were searched for relevant articles from inception until March 2022. All randomised controlled trials (RCTs) that compared laparoscopic (LTB) versus ultrasound-guided (UTB) TAP blocks in LCS were included. The primary outcome was narcotic consumption at 24 h postoperatively, whilst secondary outcomes included pain scores at 24 h postoperatively, operative time, postoperative nausea and vomiting (PONV) and complication rates. Random effects models were used to calculate pooled effect size estimates.

RESULTS

Three RCTs were included capturing 219 patients. Studies were clinically heterogenous. On random effects analysis, LTB was associated with significantly lower narcotic consumption (SMD - 0.30 mg, 95% CI = - 0.57 to - 0.03, p = 0.03) and pain scores (SMD - 0.29, 95% CI = - 0.56 to - 0.03, p = 0.03) at 24 h. However, there were no differences in operative time (SMD - 0.09 min, 95% CI = - 0.40 to 0.22, p = 0.56), PONV (OR = 0.97, 95% CI = 0.36 to 2.65, p = 0.96) or complication (OR = 1.30, 95% CI = 0.64 to 2.64, p = 0.47) rates.

CONCLUSIONS

LTB is associated with significantly less narcotic usage and pain at 24 h postoperatively but similar PONV, operative time and complication rates, compared to UTB. However, the data were inconsistent, and our findings require further investigation. LTB obviates the need for ultrasound devices whilst also decreasing procedure logistical complexity.

126 The Theatre Training Checklist: A Toolkit to Improve Operative Training

Aim

The operating theatre is expensive, costing approximately £1200 per hour to run. It is a crucial learning environment for many different trainees: anaesthetists, surgeons, operation department practitioners, etc. For individuals to achieve their training requirements, the operating theatre as a training environment must be shared between all trainees, requiring excellent teamwork and leadership. This could be improved by the adoption of innovative training strategies.

Method

The Theatre Training Checklist is a simple framework that aims to facilitate awareness, understanding, coordination and cooperation of training for all team members. It is a practical strategy that can be adopted in any setting. Usually, trainers discuss informally with their trainees about their individual skills, experience, expectations and what is achievable in a theatre list. However, there is currently limited opportunity to discuss this between different disciplines and the wider team. This tool aims to refine communication, optimize training, manage expectations, and ensure equity across the board.

Results

The checklist is completed at the start of the list during the theatre brief. It identifies all trainees and their specific needs within the operating theatre session to the whole team. An agreed strategy is developed on how to achieve identified training goals. Feedback undertaken from the MDT after local trailing of the checklist has been positive.

Conclusions

The toolkit is available for use and consists of the checklist tool and an instructional video. The checklist is being piloted in some centres and we hope to have the opportunity to present some early findings to the ASiT Innovation Summit.

SorghumBase: a web-based portal for sorghum genetic information and community advancement

SorghumBase provides a community portal that integrates genetic, genomic, and breeding resources for sorghum germplasm improvement. Public research and development in agriculture rely on proper data and resource sharing within stakeholder communities. For plant breeders, agronomists, molecular biologists, geneticists, and bioinformaticians, centralizing desirable data into a user-friendly hub for crop systems is essential for successful collaborations and breakthroughs in germplasm development. Here, we present the SorghumBase web portal ( https://www.sorghumbase.org ), a resource for the sorghum research community. SorghumBase hosts a wide range of sorghum genomic information in a modular framework, built with open-source software, to provide a sustainable platform. This initial release of SorghumBase includes: (1) five sorghum reference genome assemblies in a pan-genome browser; (2) genetic variant information for natural diversity panels and ethyl methanesulfonate (EMS)-induced mutant populations; (3) search interface and integrated views of various data types; (4) links supporting interconnectivity with other repositories including genebank, QTL, and gene expression databases; and (5) a content management system to support access to community news and training materials. SorghumBase offers sorghum investigators improved data collation and access that will facilitate the growth of a robust research community to support genomics-assisted breeding.

WT1 complete gonadal dysgenesis with membranoproliferative glomerulonephritis: case series and literature review

BACKGROUND

Intronic WT1 mutations are usually causative of Frasier syndrome with focal segmental glomerulosclerosis as the characteristic nephropathy. Membranoproliferative glomerulonephritis is not commonly associated with disorders of sex development but has been recently identified as a WT1-associated nephropathy, but usually in cases of exonic mutations in either isolated Wilms tumor or Denys-Drash syndrome.

METHODS

The clinical and genetic data from 3 individuals are reported.

RESULTS

This report describes the kidney manifestations in 3 individuals from 2 unrelated families with Frasier syndrome intronic WT1 mutations, noting that 2 of the 3 individuals have histologically confirmed membranoproliferative glomerulonephritis.

CONCLUSIONS

These case reports support expansion of the clinical spectrum of the kidney phenotypes associated with Frasier syndrome providing evidence of an association between WT1 mutation and an immune complex-related membranoproliferative glomerulonephritis. A higher resolution version of the Graphical abstract is available as Supplementary information.

Efficacy and safety of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma: long-term follow-up of a phase 2 study

BACKGROUND

Erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, was shown to be clinically active and tolerable in patients with advanced urothelial carcinoma and prespecified FGFR alterations in the primary analysis of the BLC2001 study at median 11 months of follow-up. We aimed to assess the long-term efficacy and safety of the selected regimen of erdafitinib determined in the initial part of the study.

METHODS

The open-label, non-comparator, phase 2, BLC2001 study was done at 126 medical centres in 14 countries across Asia, Europe, and North America. Eligible patients were aged 18 years or older with locally advanced and unresectable or metastatic urothelial carcinoma, at least one prespecified FGFR alteration, an Eastern Cooperative Oncology Group performance status of 0-2, and progressive disease after receiving at least one systemic chemotherapy or within 12 months of neoadjuvant or adjuvant chemotherapy or were ineligible for cisplatin. The selected regimen determined in the initial part of the study was continuous once daily 8 mg/day oral erdafitinib in 28-day cycles, with provision for pharmacodynamically guided uptitration to 9 mg/day (8 mg/day UpT). The primary endpoint was investigator-assessed confirmed objective response rate according to Response Evaluation Criteria In Solid Tumors version 1.1. Efficacy and safety were analysed in all treated patients who received at least one dose of erdafitinib. This is the final analysis of this study. This study is registered with ClinicalTrials.gov, NCT02365597.

FINDINGS

Between May 25, 2015, and Aug 9, 2018, 2328 patients were screened, of whom 212 were enrolled and 101 were treated with the selected erdafitinib 8 mg/day UpT regimen. The data cutoff date for this analysis was Aug 9, 2019. Median efficacy follow-up was 24·0 months (IQR 22·7-26·6). The investigator-assessed objective response rate for patients treated with the selected erdafitinib regimen was 40 (40%; 95% CI 30-49) of 101 patients. The safety profile remained similar to that in the primary analysis, with no new safety signals reported with longer follow-up. Grade 3-4 treatment-emergent adverse events of any causality occurred in 72 (71%) of 101 patients. The most common grade 3-4 treatment-emergent adverse events of any cause were stomatitis (in 14 [14%] of 101 patients) and hyponatraemia (in 11 [11%]). There were no treatment-related deaths.

INTERPRETATION

With longer follow-up, treatment with the selected regimen of erdafitinib showed consistent activity and a manageable safety profile in patients with locally advanced or metastatic urothelial carcinoma and prespecified FGFR alterations.

FUNDING

Janssen Research & Development.

Use of Topical Vancomycin Powder to Reduce Surgical Site Infections after Deep Brain Stimulation Surgery: UCSF Experience and Meta-Analysis

OBJECTIVE

Surgical site infection (SSI) is the most common serious complication of deep brain stimulation (DBS) implantation surgery. Here, we report a single-surgeon experience on the efficacy of topical, intrawound vancomycin powder (VP) in reducing SSI for DBS surgery and present the first systematic review and meta-analysis examining the effect of topical vancomycin on SSI in patients after DBS surgery.

METHODS

For the retrospective review, all unique patients undergoing DBS surgery at UCSF for new hardware implantation or internal pulse generator (IPG) replacement by a single surgeon from September 2013 to March 2019, with at least 1 year of follow-up data, were included. For the meta-analysis, we included all primary studies that compared SSIs with and without application of topical vancomycin in DBS surgeries.

RESULTS

368 unique patients met inclusion criteria; 195 patients received topical VP (VP group) and 173 did not (control). 99/195 patients in the VP group underwent new DBS implantation and 96/195 had IPG replacement. 71/173 patients in the control group had new DBS implantation and 102/173 had IPG replacement. There were 10 total cases of SSI: 4 patients from the VP group (3 new implants and 1 IPG replacement) and 6 patients from the control group (3 new implants and 3 IPG replacements), resulting in SSI rates of 2.1 and 3.5%, respectively (p value = 0.337). Including our retrospective analysis, 6 studies met inclusion criteria for the systematic review and meta-analysis. In the 4 studies that examined primary DBS implants, 479 total patients received topical VP and 436 did not; mean odds ratio for SSI with topical vancomycin was 0.802 (95% confidence interval [CI] 0.175-3.678). Across the 5 studies that examined IPG implantations or replacements, 606 total patients received topical VP while 1,173 patients did not; mean odds ratio for SSI with topical vancomycin was 0.492 (95% CI 0.164-1.475). In either case, topical VP application did not significantly decrease risk of SSI.

CONCLUSION

Surgical infections after DBS surgery are uncommon events, with studies demonstrating mixed results on whether topical vancomycin reduces this risk. Our single-institution retrospective analysis and systematic review of prior studies both demonstrated no significant SSI rate reduction with topical VP. This is likely due to low baseline SSI rates, resulting in a small effect size for prevention. Given the cost-effectiveness, simplicity, and low risk, topical, intrawound VP remains a treatment option to further reduce risk of SSI, particularly in settings with higher baseline infection rates.

Association of Posttraumatic Epilepsy With 1-Year Outcomes After Traumatic Brain Injury

IMPORTANCE

Posttraumatic epilepsy (PTE) is a recognized sequela of traumatic brain injury (TBI), but the long-term outcomes associated with PTE independent of injury severity are not precisely known.

OBJECTIVE

To determine the incidence, risk factors, and association with functional outcomes and self-reported somatic, cognitive, and psychological concerns of self-reported PTE in a large, prospectively collected TBI cohort.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, prospective cohort study was conducted as part of the Transforming Research and Clinical Knowledge in Traumatic Brain Injury study and identified patients presenting with TBI to 1 of 18 participating level 1 US trauma centers from February 2014 to July 2018. Patients with TBI, extracranial orthopedic injuries (orthopedic controls), and individuals without reported injuries (eg, friends and family of participants; hereafter friend controls) were prospectively followed for 12 months. Data were analyzed from January 2020 to April 2021.

EXPOSURE

Demographic, imaging, and clinical information was collected according to TBI Common Data Elements. Incidence of self-reported PTE was assessed using the National Institute of Neurological Disorders and Stroke Epilepsy Screening Questionnaire (NINDS-ESQ).

MAIN OUTCOMES AND MEASURES

Primary outcomes included Glasgow Outcome Scale Extended, Rivermead Cognitive Metric (RCM; derived from the Rivermead Post Concussion Symptoms Questionnaire), and the Brief Symptom Inventory-18 (BSI).

RESULTS

Of 3296 participants identified as part of the study, 3044 met inclusion criteria, and 1885 participants (mean [SD] age, 41.3 [17.1] years; 1241 [65.8%] men and 644 [34.2%] women) had follow-up information at 12 months, including 1493 patients with TBI; 182 orthopedic controls, 210 uninjured friend controls; 41 patients with TBI (2.8%) and no controls had positive screening results for PTE. Compared with a negative screening result for PTE, having a positive screening result for PTE was associated with presenting Glasgow Coma Scale score (8.1 [4.8] vs.13.5 [3.3]; P < .001) as well as with anomalous acute head imaging findings (risk ratio, 6.42 [95% CI, 2.71-15.22]). After controlling for age, initial Glasgow Coma Scale score, and imaging findings, compared with patients with TBI and without PTE, patients with TBI and with positive PTE screening results had significantly lower Glasgow Outcome Scale Extended scores (mean [SD], 6.1 [1.7] vs 4.7 [1.5]; P < .001), higher BSI scores (mean [SD], 50.2 [10.7] vs 58.6 [10.8]; P = .02), and higher RCM scores (mean [SD], 3.1 [2.6] vs 5.3 [1.9]; P = .002) at 12 months.

CONCLUSIONS AND RELEVANCE

In this cohort study, the incidence of self-reported PTE after TBI was found to be 2.8% and was independently associated with unfavorable outcomes. These findings highlight the need for effective antiepileptogenic therapies after TBI.

231 ESTABLISHING AN INTERVENTIONS BUNDLE TO IMPROVE INPATIENT CARE FOR PATIENTS WITH PARKINSON’S DISEASE: A MULTIDISCIPLINARY QUALITY IMPROVEMENT PROJECT

Background

Patients with Parkinson’s (PwP) are at a higher risk of complications once admited to hospital compared to their age-matched peers. Medication mismanagement is a well-known obstacle, which puts PwP at risk of sub-optimal treatment leading to an unnecessary deterioration of baseline and potentially increases risk of adverse sequelae.

Methods

Retrospective electronic patient records (EPR)/chart review of 47 admissions was conducted, across three hospital sites.

Data attaining to correct prescribing of medication on admission and discharge, prescribing of contraindicated medications, reasons for medication lapses and complications of inpatient stay were collected. EPR of 17 patients’ were reviewed to assess if Parkinson’s disease (PD) medication administrations occurred within 30 minutes of patient schedule, as recommended by NICE guidelines. Key areas for improvement were identified based on the results.

Results

47 charts (30 Males, 17 Females) with mean age 72 (range:57–90), were reviewed. Average number of co-morbidities:4.5 and Clinical Frailty Scale ranged 5–9 (n = 30). LOS averaged 12.4 days and 43% of patients had ≥2 hospital admissions in the preceeding year.

38% (17/44) of admissions correctly documented patient specific medication times. Only 48% of patients (n = 638) received their medications within 30 minutes of the scheduled time. 47% (22/47) experienced complications attributable to PD. Contraindicated medications were noted in 5 cases. 84% of discharging prescriptions did not mention timing of PD medication and 3 prescriptions had errors with regards to dosage/omission of medication.

Conclusion

We implemented across two sites: 1) Care protocol flag in patient’s chart highlighting simple avoidable complications. 2) Laminated over the bed signpost alerting ‘time critical medication’. 3) ‘Time critical medication’ stickers in drug kardex 4) Education sessions for Medical, Nursing and Ward staff. 6) Establishing out of hours access to PD medications and protocols for NPO/poor swallow. We plan to reassess significance of efforts post intervention.

Epidemiological and Immunological Features of Obesity and SARS-CoV-2

Obesity is a key correlate of severe SARS-CoV-2 outcomes while the role of obesity on risk of SARS-CoV-2 infection, symptom phenotype, and immune response remain poorly defined. We examined data from a prospective SARS-CoV-2 cohort study to address these questions. Serostatus, body mass index, demographics, comorbidities, and prior COVID-19 compatible symptoms were assessed at baseline and serostatus and symptoms monthly thereafter. SARS-CoV-2 immunoassays included an IgG ELISA targeting the spike RBD, multiarray Luminex targeting 20 viral antigens, pseudovirus neutralization, and T cell ELISPOT assays. Our results from a large prospective SARS-CoV-2 cohort study indicate symptom phenotype is strongly influenced by obesity among younger but not older age groups; we did not identify evidence to suggest obese individuals are at higher risk of SARS-CoV-2 infection; and remarkably homogenous immune activity across BMI categories suggests immune protection across these groups may be similar.

1020 Delay to Surgery in Acute Perforated and Ischaemic Gastrointestinal Pathology

Introduction

Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality, and complications. The timeline between symptom onset and operation is ill-defined with international variance in assessment and management. This systematic review aims to define where delays to surgery occur and assess the evidence for previous interventions.

Method

A systematic review was performed searching MEDLINE and EMBASE databases (January 1st 2005 to May 6th 2020). All studies assessing the impact of time to theatre in patients with acute abdominal pathology requiring emergency laparotomy were considered.

Results

Eighty-five results were assessed to include 19 papers in the analysis. Fifteen unique timepoints were identified in the patient pathway between symptom onset and operation which could be classified into four distinct phases. Time from admission to theatre (1 to 72 hours), and mortality rate (10.6-74.5%) varied greatly between studies. Mean time to surgery was significantly higher in deceased patients compared to survivors. Delays were related to imaging, diagnosis, decision-making, theatre availability and staffing. Four of five interventional studies showed a reduced mortality following introduction of an acute laparotomy pathway.

Conclusions

There is wide variation in the definition and measurement of time delays prior to emergency surgery with few studies exploring interventions. Given the heterogenous nature of the patient population and pathologies, an assessment and management framework from onset of symptoms to operation is proposed. This could be incorporated into national mortality prediction and audit tools and assist in the assessment of interventions.

1289 Gender Representation in The Authorship of Surgical Journals

Introduction

Despite the increase in female doctors graduating from medical schools internationally, gender disparity in surgery remains. This disparity is also evident in academic surgery. This study aims to quantify the extent of gender disparity in the authorship of articles in major surgical journals.

Method

The Top 10 Surgical Journals were identified using SCImago Journal Rank indicator. Authorship details for papers published in 2019 were collected. Authors were assigned as female, male or unknown using Gender API software (Gender API, Germany). For each journal, the percentage of first author, last author, corresponding author and all authors split by gender was interrogated. Gender differences by publication type were also identified.

Results

9 of the 10 journals had full names publicly available. Overall, 2414 manuscripts were interrogated which included 16,277 number of authors. Respectively, females and males accounted for 29.8% [22.9-34.9%] (N = 655) and 62.4% [56.3-70.2%] (N = 1419) of first authors, 20.6% [11.8-27.1%] (N = 453) and 74.2% [65.6-84.1%] (N = 1706) of last authors, 23.9% [14.9-29.6%] (N = 510) and 69.9% [60.5-79.3%] (N = 2341) of corresponding authors and in total 27% [19.4-31.6%] (N = 4298) and 65.5% [58.6-73.4%] (N = 9982) of all authors. The wide range in these results could be a result of various factors.

Conclusions

This study has identified a gender imbalance in authorship positions, with the greatest difference observed in the most senior author position. Whether this is reflective of the current disparity observed in senior academic surgery positions or due to gender discrimination is unclear.

1308 Investigating the Use of a Novel Pre-Hospital Triage Tool for Acute Abdominal Surgical Emergencies – A Two-Phase Single Centre Cohort Study

Background

Despite the recent improvements in mortality in patients undergoing emergency laparotomy(EL) within the UK, delay to theatre continues to be associated with increased mortality. This study aimed to assess if patients requiring urgent surgical intervention for acute abdominal surgical pathology could be identified in the pre-hospital setting.

Method

A two-phase, single-centre, cohort study was performed. Phase 1 retrospectively investigated patients who underwent emergency laparotomy between 01/01/2019-31/12/2019 at Leeds Teaching Hospital Trust (LTHT) through the NELA database. Phase 2 prospectively assessed NEWS2 for all patients presenting to LTHT Surgical Admissions Unit with abdominal pain between 01/01/2020-31/01/2020.

Results

Phase 1: 45 patients were coded through NELA and confirmed through operation note review as undergoing EL for gastrointestinal perforation. 66%(n = 30) were assessed by the ambulance service and 80% (n = 24) had a NEWS2 of 3 or greater. Phase 2: 319 patients were assessed in SAU/ED, of which 69 initially treated by the ambulance service. 30% (n = 21) of these patients had an initial NEWS2 of 3 or above. Sensitivity of a NEWS2 score of &gt;/3 in predicting the need for immediate surgical intervention including EL was 95%(95%CI, 74-99) and specificity was 95% (95%CI, 83-99) with a PPV of 86%(95%CI 67-95) and NPV of 98% (95%CI, 87-99).

Conclusions

A NEWS2 score of &gt;/3 predicts the need for emergency surgical intervention including laparotomy for gastrointestinal perforation with reasonable sensitivity in this cohort. A pre-hospital triage tool for patients presenting with abdominal pain could utilise NEWS2 as an adjunct to decision-making in an acute abdominal pathway.

389 Impact of Surgical Drain Output Monitoring on Patient Outcomes in Gastrointestinal Surgery: A Systematic Review

Aim

Surgical drains are widely utilised in Gastrointestinal Surgery to prevent intra-abdominal collections and identify post-operative complications. Surgical drain monitoring ranges from simple output measurements through to specific analysis for constituents such as amylase. This systematic review aimed to determine whether surgical drain monitoring can detect post-operative complications and impact on patient outcomes.

Method

A systematic review was performed, and the following databases searched between 02/03/20 and 26/04/20: MEDLINE, EMBASE, The Cochrane Library and Clinicaltrials.gov. All studies describing surgical drain monitoring of output and content in adult patients undergoing gastrointestinal surgery were considered. Other invasive methods of intra-abdominal sampling were excluded.

Results

The search returned 396 articles. Following abstract review, 383 were excluded and 13 articles were included for full review. The studies were classified according to speciality: Oesophagogastric (1), Pancreatic (6), Hepatobiliary (2), Colorectal (3) and Emergency General Surgery (1). Post-operative monitoring of amylase and bilirubin decreased the incidence of post-operative complications (pancreatic fistulas, intra-abdominal infections, surgical site infections), length of stay and mortality rate in Pancreatic and Hepatobiliary Surgery. Testing of drain contents following Colorectal Surgery can aid anastomotic leak and the detection of peritonitis, however this did not confer any improvement in patient outcome. Surgical drain monitoring did not improve patient outcomes in Oesophagogastric Surgery.

Conclusions

Surgical drain monitoring has established advantages in the post-operative care for patients undergoing Gastrointestinal Surgery. Enhanced surgical drain monitoring involving the testing of drain amylase, bilirubin, lactate, and cytokines may improve detection of complications in the immediate post-operative period.

1404 NELA Risk Mortality Scores from Admission to Theatre in Emergency Gastrointestinal Perforation – A Retrospective Cohort Study

Background

Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality and complications. The aim of this study was to assess delay, from symptom onset to theatre in patients with gastrointestinal perforation and its effect on perioperative risk.

Method

A single-centre retrospective study was performed in the Leeds Trust Hospitals, UK investigating the NELA database for patients requiring emergency laparotomy for perforated gastrointestinal viscus who presented to the acute surgical unit or emergency department between 1st February 2018 and 31st January 2020.

Results

101 patients met the inclusion criteria (47% F and 53% M), mean age 59 [21-91]. 37% of patients’ NELA scores worsened from admission to pre-op (median change of + 5.9% IQR 1.3-11.5]), 14% stayed the same and 49% improved (median change of -4.4%[IQR 0.4-9.1]) 3% had their NELA score documented at the time of consent. 18% did not wait for a CT report or went straight to theatre. Mean time from admission to scan report was 9.3 hours (0.9-22.0). Median time from symptom onset to presentation (2 days [IQR 1-13]) was greater in patients with an Index of Multiple Deprivation Decile of 1-5, (n = 64, median 2 days [IQR 1-6]) compared to those in deciles 6-10, (n = 37, median 1 day[IQR 1-3]), p = 0.097.

Conclusions

NELA mortality risk score changes from presentation to surgery in patients with acute gastrointestinal perforation requiring emergency laparotomy. There is suggestion that delay in symptom onset to presentation may correlate with Index of Multiple Deprivation Decile.

ECCO Topical Review: Refractory Inflammatory Bowel Disease

Inflammatory bowel disease is a chronic disease with variable degrees of extent, severity, and activity. A proportion of patients will have disease that is refractory to licensed therapies, resulting in significant impairment in quality of life. The treatment of these patients involves a systematic approach by the entire multidisciplinary team, with particular consideration given to medical options including unlicensed therapies, surgical interventions, and dietetic and psychological support. The purpose of this review is to guide clinicians through this process and provide an accurate summary of the available evidence for different strategies.

Pragmatic use of short-course radiotherapy, chemotherapy and surgery for stage IV rectal cancer with locally advanced or symptomatic primary tumours

INTRODUCTION

We assessed management of patients with de novo metastatic rectal cancer, referred for radiotherapy to the rectum, who were candidates for short-course radiotherapy (SCRT) and chemotherapy, followed by resection of all disease. We assessed surgical outcomes, overall survival (OS) and progression-free survival (PFS).

METHODS

Retrospective review of patients meeting criteria: (i) treatment with SCRT to rectum; (ii) locally advanced primary rectal cancer; and (iii) resectable distant metastases at diagnosis. Data were collected from charts, correspondence and electronic patient records. OS and PFS were calculated using the Kaplan-Meier method.

RESULTS

Between 2016 and 2020, 48 patients with stage IV rectal cancer at diagnosis were treated with SCRT. Only 15 patients (31%) had resectable metastatic disease and were intended for SCRT (25 Gy/5#), then chemotherapy, followed by resection of all sites of disease and are included in our study. 12 of the 15 surgical candidates (80%) had rectal surgery as planned, and 11 of the 15 (73%) had resection of the rectal primary and all metastatic disease. One patient had a pathological complete response (pCR), and 50% of surgical patients had a Mandard TRG of 1 or 2. Median PFS and OS for the 15 surgical candidates were 12.6 and 25.2 months, respectively, with a median FU of 21.2 months.

CONCLUSION

For this cohort of patients, our treatment paradigm is pragmatic and results in excellent pathological response. However, the effectiveness of this approach should be the subject of future prospective studies.

A Randomized Clinical Trial Evaluating the Efficacy and Quality of Life of Antibiotic-only Treatment of Acute Uncomplicated Appendicitis: Results of the COMMA Trial

OBJECTIVE

Evaluate the efficacy and quality of life associated with conservative treatment of acute uncomplicated appendicitis.

SUMMARY BACKGROUND DATA

Conservative management with antibiotics only has emerged as a potential treatment option for acute uncomplicated appendicitis. However the reported failure rates are highly variable and there is a paucity of data in relation to quality of life.

METHODS

Symptomatic patients with radiological evidence of acute, uncomplicated appendicitis were randomized to either intravenous antibiotics only or undergo appendectomy.

RESULTS

One hundred eighty-six patients underwent randomization. In the antibiotic-only group, 23 patients (25.3%) experienced a recurrence within 1 year following randomization. There was a significantly better EQ-VAS quality of life score in the surgery group compared with the antibiotic-only group at 3 months (94.3 vs 91.0, P < 0.001) and 12 months postintervention (94.5 vs 90.4, P < 0.001). The EQ-5D-3L quality-of-life score was significantly higher in the surgery group indicating a better quality of life (0.976 vs 0.888, P < 0.001). The accumulated 12-month sickness days was 3.6 days shorter for the antibiotics only group (5.3 vs 8.9 days; P < 0.01). The mean length of stay in both groups was not significantly different (2.3 vs 2.8 days, P = 0.13). The mean total cost in the surgery group was significantly higher than antibiotics only group (€4,816 vs €3,077, P < 0.001).

CONCLUSIONS

Patients with acute, uncomplicated appendicitis treated with antibiotics only experience high recurrence rates and an inferior quality of life. Surgery should remain the mainstay of treatment for this commonly encountered acute surgical condition.

Abstract 291: Development of optimized chemical probes targeting PI3Ka to deconvolute the role of class I PI3Ks isoforms in insulin signaling

Phosphatidylinositol-3-kinase (PI3K) activity is aberrant in tumors, and PI3K inhibitors are investigated as cancer therapeutics.[1-5] The major obstacles to the successful implementation of PI3K-targeted cancer therapy are on-target adverse effects on insulin signaling. Isotype selective PI3K inhibitors have been exploited to answer fundamental questions regarding the role of PI3K isoforms in cell biology. However, the availability of claimed isoform-selective PI3Kα inhibitors is limited to BYL719 (Alpelisib)[6] and GDC0032 (Taselisib)[7], which do not maintain PI3Kα selectivity at a concentration required in cellular experimental settings and clinical applications. Highly selective PI3Kα inhibitors are expected to represent ideal tools to elucidate the role of PI3Kα isoform in tumor development and insulin signaling. As the systemic inactivation of PI3Kα is embryonic lethal, genetic approaches are currently limited to organ-specific targeting, and a specific inactivation of PI3Kα in an adult organism has not been achieved up-to-date. Herein, we generate high-quality PI3Kα chemical probes to dissect the role of PI3Kα in cancer and metabolism. We exploit covalent inhibitors, permanently blocking target functions, as a strategy to enhance the ligand binding selectivity for proteins in the same family. The non-conserved nucleophilic amino acid Cys862 in PI3Kα represents a promising target for covalent modifiers. We converted the reversible scaffold of PQR514[5] into irreversible compounds. An extensive Structure Activity Relationship (SAR) study was performed using CNX-1351[8] reacting group and introducing different heteroaliphatic rings in the linker. X-ray crystallography and bottom-up LC-MS/MS based proteomics validated the covalent modification of Cys862. Our pilot chemical probes exceeded in vitro and cellular potency over CNX-1351. The generation of a novel class of covalent PI3Kα-specific inhibitors with improved selectivity and persistency of PI3Kα-inhibition will shed light on the role of PI3Kα in cancer and metabolism. Our results will pave the way for the dissociation of PI3Ki antitumor activity from adverse effects on insulin action. [1] Beaufils F et al. J Med Chem. 2017, 60 (17), 7524-7538. [2] Rageot R et al. J Med Chem. 2019, 62 (13), 6241-6261. [3] Wymann MP et al. Nat Rev Mol Cell Biol. 2008, 9 (2), 62-176. [4] Marone R et al. Biochim Biophys Acta. 2008, 1784 (1), 159-185. [5] Borsari C et al. ACS Med Chem Lett. 2019, 10 (10), 1473-1479. [6] Markham A Drugs 2019, 79 (11), 1249-1253. [7] Zumsteg ZS et al. Clin Cancer Res. 2019, 22 (8), 2009-2019. [8] Nacht M et al. J Med Chem. 2013, 56 (3), 712-721.

Citation Format: Martina De Pascale, Chiara Borsari, Erhan Keles, Jacob McPhail, Alexander Schäfer, Rohitha Sriramaratnam, Matthias Gstaiger, John Burke, Matthias Wymann. Development of optimized chemical probes targeting PI3Ka to deconvolute the role of class I PI3Ks isoforms in insulin signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 291.

Abstract 1377: Volume scanning, a rational approach to covalent PI3Kα inhibitors

Inhibitors of the phosphatidylinositol 3-kinase (PI3K) - protein kinase B (PKB/Akt) - mechanistic target of rapamycin (mTOR) axis are considered valuable assets in cancer therapy. A considerable effort has been dedicated to the development of drugs targeting class I PI3Ks, which are evaluated in preclinical and clinical studies.[1-5] Here we present a strategy to convert a phase II clinical candidate, a pan-PI3K inhibitor (PQR309, bimiralisib)[5,6], into a highly selective, covalent PI3Kα inhibitor with the aim to minimize off-target and on-target metabolic side effects of PI3K inhibitor cancer therapy. We exploited a rational approach to increase target selectivity by covalently targeting PI3Kα at the non-conserved nucleophilic Cys862. A combination of warhead activity design, proximity screening and an optimized orientation allowed a tight control of reversible inhibitor binding in combination with an isoform-specific covalent reaction. To avoid off-target reactions, all warheads' reactivities were determined and optimize for selectivity and of Cys862 modification. An extensive Structure Activity Relationship (SAR) study was performed and a wide range of linear and restricted rotation linkers were introduced. A comprehensive understanding of the kinetics of irreversible inhibition acquired by kinetic TR-FRET assays and subsequent determination of kchem, kinact and calculated Ki allowed the establishment of a SAR, for compound selection with minimal off-target reactivity and high PI3Kα selectivity. X-ray crystallography and MS-based proteomics validated the covalent modification of Cys862. Our pilot compounds exceed specificity and potency over an experimental dimethyl-substituted enone, CNX-1351.[7] Moreover, our compounds display increased stability in rat liver microsomal assays and outperform the rapidly metabolized CNX-1351. Our strategy to investigate and tune warheads' reactivity represents a major step forward in the rational design of covalent chemical tools, overcoming the serendipity in the discovery of irreversible compounds. Moreover, we provide highly selective chemical tools to dissect PI3K isoform signaling in physiology and disease. A clarification of the role of the different PI3K isoforms in insulin signaling allows to address the challenges in isoform selectivity and to develop PI3K inhibitors showing ideal isoform specificity. [1] Rageot D et. al. J Med Chem. 2019, 62 (13), 6241-6261. [2] Borsari C et. al. ACS Med Chem Lett. 2019, 10 (10), 1473-1479. [3] Marone R et al. Biochim Biophys Acta 2008, 1784 (1), 159-185. [4] Wymann MP and Schneiter R Nat Rev Mol Cell Biol. 2008, 9 (2), 162-176. [5] Beaufils F et. al. J Med Chem. 2017, 60 (17), 7524-7538. [6] Wicki A et. al. Eur J Cancer. 2018, 96, 6-16. [7] Nacht M et. al. J Med Chem. 2013, 56 (3), 712-721.

Citation Format: Chiara Borsari, Erhan Keles, Jacob McPhail, Alexander Schäfer, Rohitha Sriramaratnam, Martina De Pascale, Matthias Gstaiger, John Burke, Matthias P. Wymann. Volume scanning, a rational approach to covalent PI3Kα inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1377.

Discrimination in the surgical discipline: an international European evaluation (DISDAIN)

Background

Negative workplace experiences (NWPEs), such as gender discrimination, bullying, sexual harassment and ethnic discrimination, are concerns in today’s surgical society. These negative experiences potentially impair surgeons’ performance and might impact patient care or outcomes negatively. This study aimed to assess the experience of NWPEs across the European surgical workforce.

Methods

A prospective online 34-point questionnaire was designed using a combination of Likert scale, multiple-choice and short-answer questions. Invitations were distributed through surgical associations via email/social media between 1 September and 15 November 2019. Data were analysed using non-parametric methods.

Results

Some 840 complete responses were included in the analysis. The distribution across genders and stage of surgical training was even. Of the respondents, 20 per cent (168 respondents) considered quitting their job, 4.5 per cent (38) took time off and 0.5% (4) left surgery due to NWPEs; 12.9 per cent of females and 4.4 per cent of males experienced some form of physical harassment. Females and those in training were significantly more likely to experience or witness gender discrimination and sexual harassment. Just over half of the respondents (448) did not report negative experiences, with most of these (375 respondents) being unaware of whom to report to. Nearly a fifth of respondents felt that NWPEs influenced patient care or outcomes negatively.

Conclusion

NWPEs were frequent, especially among females and those in training. While a substantial proportion of respondents experienced physical harassment, many individuals were unaware of how to raise concerns. Adverse effects on patient outcomes, surgical training and workforce retention indicate a need for urgent action.

A Post-Surgical Stereovision Surprise in an Adult With an Exotropia Since Infancy Previously Managed, at Two Years With Surgery

Aim

To describe an unexpected sensory outcome in an adult male who is seeking ocular re-alignment for a psychosocially symptomatic large non-specific exotropia with suppression. The primary diagnosis was infant onset exodeviation of unclear diagnosis, was managed with bilateral strabismus surgery at two years of age, little memory of follow-up.

Result

Measurable binocular single vision (BSV) was demonstrable following surgery at 17 years of age, albeit slowly between two weeks and six months postoperatively and subsequently enhanced. His newly acquired sub-optimal BSV led to symptomatic occupation-associated asthenopia. Following two subsequent operations over a 15-year period, he has stable, symptom-free ocular realignment within three prism diopters of orthophoria and performing tasks that require extended periods of near-vision activity.

Conclusion

Delayed high levels of stereovision were unexpectedly achieved in an adult with infant onset exotropia with pre-operative sensory suppression that was surgically aligned to near orthophoria. The re-establishment of BSV in such a clinical scenario has to attain a level that is robust enough to meet an individual's social and occupational needs.

Effects of flanking sequences and cellular context on subcellular behavior and pathology of mutant HTT

Huntington's disease (HD) is caused by an expansion of a poly glutamine (polyQ) stretch in the huntingtin protein (HTT) that is necessary to cause pathology and formation of HTT aggregates. Here we ask whether expanded polyQ is sufficient to cause pathology and aggregate formation. By addressing the sufficiency question, one can identify cellular processes and structural parameters that influence HD pathology and HTT subcellular behavior (i.e. aggregation state and subcellular location). Using Drosophila, we compare the effects of expressing mutant full-length human HTT (fl-mHTT) to the effects of mutant human HTTexon1 and to two commonly used synthetic fragments, HTT171 and shortstop (HTT118). Expanded polyQ alone is not sufficient to cause inclusion formation since full-length HTT and HTTex1 with expanded polyQ are both toxic although full-length HTT remains diffuse while HTTex1 forms inclusions. Further, inclusions are not sufficient to cause pathology since HTT171-120Q forms inclusions but is benign and co-expression of HTT171-120Q with non-aggregating pathogenic fl-mHTT recruits fl-mHTT to aggregates and rescues its pathogenicity. Additionally, the influence of sequences outside the expanded polyQ domain is revealed by finding that small modifications to the HTT118 or HTT171 fragments can dramatically alter their subcellular behavior and pathogenicity. Finally, mutant HTT subcellular behavior is strongly modified by different cell and tissue environments (e.g. fl-mHTT appears as diffuse nuclear in one tissue and diffuse cytoplasmic in another but toxic in both). These observations underscore the importance of cellular and structural context for the interpretation and comparison of experiments using different fragments and tissues to report the effects of expanded polyQ.

524 Anaesthetic Use and Packing in Subcutaneous Abscess Management: A Retrospective Before and After Analysis Within A Two-Cycle Audit

Introduction

In the United Kingdom, there are no widely used guidelines within the management of subcutaneous abscesses by incision and drainage (I&D) to direct the use of local anaesthesia (LA) vs genal anaesthesia (GA); or the use of wound packing vs no packing.

Method

Two cohorts of patients undergoing I&D procedures were retrospectively identified from attendance records over a 3.5-month period. The first cohort was between 16th October 2018 to 31st January 2019. The second cohort of patients was during the COVID-19 pandemic following the introduction of new RCS guidance (intervention) between 29th March 2020 and 15th June 2020.

Results

Seventy-one patients before and 63 after the intervention were included. There were significantly more procedures performed under LA after the introduction of the intervention (n = 52; 82.5%) vs before (n = 4; 5.6%) p < 0.0001. The incidence of wound packing decreased after the intervention (n = 43; 68.3% vs n = 62; 87.3%) p = 0.00452.

Conclusions

The results demonstrate that during the pandemic, change in practice resulted in more subcutaneous abscesses being treated with LA. The majority of abscesses were packed in both cohorts although the incidence declined after the intervention. Future research should explore the patient satisfaction regarding pain management and the abscess recurrence rate.

P15: EVALUATING THE INTERNATIONAL USABILITY OF A LOW-COST LAPAROSCOPIC TRAINER IN LOW- AND HIGH-INCOME SETTINGS

Introduction

Limited access to equipment and trained personnel restrict the adoption of laparoscopic surgery globally. There are a wide range of laparoscopic trainers available; however, most of these are not affordable. We propose an ultra-low-cost laparoscopic trainer (Lap-Pack), designed for portability, ease of assembly and compatibility with smart devices. The study aims to evaluate the usability of Lap-Pack as a training tool in low- and high-income settings.

Method

An international usability study was conducted in India and the UK in 2019. The participants (n=60), consisting of senior surgeons (n=18), junior trainees (n=20) and medical students (n=22), were asked to complete two tasks using Lap-Pack. Participants then scored Lap-Pack in a 25-point questionnaire, including a pre-established Face-Validity Criteria and four major evaluation categories – Usability, Camera, View, Material.

Result

Lap-Pack scored highly in Face-Validity with a combined mean score of 4.63 (95%CI: 4.31, 4.95, p &lt;0.05) of a possible 6. In both cohorts, the Usability and Camera categories scored highest, with combined values respectively of 6.10 (95%CI: 6.01, 6.19, p &lt;0.05) and 6.09 (95%CI: 5.88, 6.31, p &lt;0.05) of a possible 7. For both centres, the highest-scoring individual criteria were its light weight and portability.

Conclusion

Overall, Lap-Pack was received positively by medical students and consultants alike, suggesting it is a suitable device for development of skills as part of a larger laparoscopic training curriculum. Its ease of assembly, portability and versatility show promise of increasing access to training opportunities worldwide.

Take-home message

Lap-Pack is an ultra-low-cost, portable laparoscopic simulator featuring compatibility with smart devices designed to help increase access to laparoscopic training worldwide. An international usability study found medical students, junior trainees and senior surgeons rated its usability and camera features highly, suggesting its employability as a laparoscopic training tool on a global scale.

Seed-to-seed early-season cold resiliency in sorghum

Early planted sorghum usually experiences cooler day/night temperatures, which may result in delayed growth, floral initiation, and infertile pollen, limiting productivity in high altitudes and temperate regions. Genetic variability for cold tolerance in sorghum has been evaluated by characterizing germination, emergence, vigor, and seedling growth under sub-optimal temperatures. However, the compounded effect of early season cold on plant growth and development and subsequent variability in potential grain yield losses has not been evaluated. Agro-morphological and physiological responses of sorghum grown under early-, mid-, and standard planting dates in West Texas were characterized from seed-to-seed. A set of diverse lines and hybrids with two major sources of tolerance, and previously selected for seedling cold tolerance were used. These were evaluated with a standard commercial hybrid known for its seedling cold tolerance and some cold susceptible breeding lines as checks. Variabilities in assessed parameters at seedling, early vegetative, and maturity stages were observed across planting dates for genotypes and sources of cold tolerance. Panicle initiation was delayed, and panicle size reduced, resulting in decreased grain yields under early and mid-planting dates. Coupled with final germination percent, panicle width and area were significant unique predictors of yield under early and mid-planting dates. Significant variability in performance was observed not only between cold tolerant and susceptible checks, but noticeably between sources of cold tolerance, with the Ethiopian highland sources having lesser yield penalties than their Chinese counterparts. Thus, screening for cold tolerance should not be limited to early seedling characterization but should also consider agronomic traits that may affect yield penalties depending on the sources of tolerance.

Neoadjuvant Short-Course Radiotherapy for Upper Third Rectal Tumors: Systematic Review and Individual Patient Data Metaanalysis of Randomized Controlled Trials

BACKGROUND

There is no consensus on the use of neoadjuvant radiotherapy for tumors of the upper third of the rectum. Due to conflicting findings in high-quality trials and significant long-term side effects associated with neoadjuvant radiotherapy, the benefit of neoadjuvant radiotherapy for upper third rectal tumors is less certain than for lower two third rectal tumors. This metaanalysis compares oncological outcomes with neoadjuvant radiotherapy and surgery versus surgery alone for upper third rectal tumors.

PATIENTS AND METHODS

PubMed, Embase, and the Cochrane library databases were searched. Randomized controlled trials (RCT) comparing neoadjuvant radiotherapy and surgery versus surgery alone for resectable rectal cancer were included. Individual patient data were sought from the principal investigator of each eligible trial for comparative data on patients with upper third rectal tumors. The main outcomes measured were survival outcomes, oncological outcomes, postoperative morbidity, and late toxicity.

RESULTS

Individual patient data from two RCTs examining outcomes in 758 patients were obtained. Published data from one further RCT containing comparable data on upper third rectal tumors were included in analysis of local recurrence. In patients with curative surgery, there was no significant reduction in local recurrence or significant improvement in overall survival or disease-free survival with neoadjuvant radiotherapy (LR RR: 0.38, 95% CI 0.14-1.04, p = 0.06) (OS RR: 1.10, 95% CI 0.98-1.24, p = 0.11) (DFS RR: 1.11, 95% CI 0.97-1.26, p = 0.13).

CONCLUSIONS

The benefit of neoadjuvant radiotherapy for upper third rectal tumors is not certain, and surgery alone for patients with potentially curative disease at preoperative staging may be sufficient.

Impact of the COVID-19 pandemic on management and outcomes in acute appendicitis: Should these new practices be the norm?

Background

In early 2020, the COVID-19 pandemic significantly altered management of surgical patients globally. International guidelines recommended that non-operative management be implemented wherever possible (e.g. in proven uncomplicated appendicitis) to reduce pressure on healthcare services and reduce risk of peri-operative viral transmission. We sought to compare our management and outcomes of appendicitis during lockdown vs a non-pandemic period.

Methods

All presentations to our department with a clinical diagnosis of acute appendicitis between 12/03/2020 and 30/06/2020 were compared to the same 110-day period in 2019. Quantity and severity of presentations, use of radiological investigations, rate of operative intervention and histopathological findings were variables collected for comparison.

Results

There was a reduction in appendicitis presentations (from 74 to 56 cases), and an increase in radiological imaging (from 70.27% to 89.29%) (P = 0.007) from 2019 to 2020. In 2019, 93.24% of patients had appendicectomy, compared to 71.42% in 2020(P < 0.001). This decrease was most pronounced in uncomplicated cases, whose operative rates dropped from 90.32% to 62.5% (P = 0.009). Post-operative histology confirmed appendicitis in 73.9% in 2019, compared to 97.5% in 2020 (P = 0.001). Normal appendiceal pathology was reported for 17 cases (24.64%) in 2019, compared to none in 2020 (P < 0.001) – a 0% negative appendicectomy rate (NAR).

Discussion

The 0% NAR in 2020 is due to a combination of increased CT imaging, a higher threshold to operate, and is impacted by increased disease severity due to delayed patient presentation. This study adds to growing literature promoting routine use of radiological imaging to confirm appendicitis diagnosis. As we enter a second lockdown, patients should be encouraged to avoid late presentations, and surgical departments should continue using radiological imaging more liberally in guiding appendicitis management.

Compromised SARS-CoV-2-specific placental antibody transfer

SARS-CoV-2 infection causes more severe disease in pregnant women compared to age-matched non-pregnant women. Whether maternal infection causes changes in the transfer of immunity to infants remains unclear. Maternal infections have previously been associated with compromised placental antibody transfer, but the mechanism underlying this compromised transfer is not established. Here, we used systems serology to characterize the Fc profile of influenza-, pertussis-, and SARS-CoV-2-specific antibodies transferred across the placenta. Influenza- and pertussis-specific antibodies were actively transferred. However, SARS-CoV-2-specific antibody transfer was significantly reduced compared to influenza- and pertussis-specific antibodies, and cord titers and functional activity were lower than in maternal plasma. This effect was only observed in third-trimester infection. SARS-CoV-2-specific transfer was linked to altered SARS-CoV-2-antibody glycosylation profiles and was partially rescued by infection-induced increases in IgG and increased FCGR3A placental expression. These results point to unexpected compensatory mechanisms to boost immunity in neonates, providing insights for maternal vaccine design.

Dissecting strategies to tune the therapeutic potential of SARS-CoV-2-specific monoclonal antibody CR3022

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), coupled with a lack of therapeutics, has paralyzed the globe. Although significant effort has been invested in identifying antibodies that block infection, the ability of antibodies to target infected cells through Fc interactions may be vital to eliminate the virus. To explore the role of Fc activity in SARS-CoV-2 immunity, the functional potential of a cross–SARS-reactive antibody, CR3022, was assessed. CR3022 was able to broadly drive antibody effector functions, providing critical immune clearance at entry and upon egress. Using selectively engineered Fc variants, no protection was observed after administration of WT IgG1 in mice or hamsters. Conversely, the functionally enhanced Fc variant resulted in increased pathology in both the mouse and hamster models, causing weight loss in mice and enhanced viral replication and weight loss in the more susceptible hamster model, highlighting the pathological functions of Fc-enhancing mutations. These data point to the critical need for strategic Fc engineering for the treatment of SARS-CoV-2 infection.

Epidemiological and immunological features of obesity and SARS-CoV-2

Obesity is a key correlate of severe SARS-CoV-2 outcomes while the role of obesity on risk of SARS-CoV-2 infection, symptom phenotype, and immune response are poorly defined. We examined data from a prospective SARS-CoV-2 cohort study to address these questions. Serostatus, body mass index, demographics, comorbidities, and prior COVID-19 compatible symptoms were assessed at baseline and serostatus and symptoms monthly thereafter. SARS-CoV-2 immunoassays included an IgG ELISA targeting the spike RBD, multiarray Luminex targeting 20 viral antigens, pseudovirus neutralization, and T cell ELISPOT assays. Our results from a large prospective SARS-CoV-2 cohort study indicate symptom phenotype is strongly influenced by obesity among younger but not older age groups; we did not identify evidence to suggest obese individuals are at higher risk of SARS-CoV-2 infection; and, remarkably homogenous immune activity across BMI categories suggests natural- and vaccine-induced protection may be similar across these groups.