Deep dive into the chronic toxicity of tyre particle mixtures and their leachates

Particles from the tread of vehicle tyres are a global pollutant, which are emitted into the environment at an approximate rate of 1.4 kg.year-1 for an average passenger-car. In this study, popular tyre brands were used to generate a tyre tread microparticle mixture. The chronic toxicity of both particles and chemical leachates were compared on a planktonic test species (Daphnia magna). Over 21 days of exposure, pristine tyre tread microparticles were more toxic (LC50 60 mg.L-1) than chemical lechates alone (LC50 542 mg.L-1). Microparticles and leachates showed distinct effects on reproduction and morphological development at environmentally relevant concentrations, with dose-dependent uptake of particles visible in the digestive tract. Chemical characterization of leachates revealed a metal predominance of zinc, titanium, and strontium. Of the numerous organic chemicals present, at least 54 were shared across all 5 tyre brands, with many classified to be very toxic. Our results provide a critically needed information on the toxicity of tyre tread particles and the associated chemicals that leach from them to inform future mitigation measures. We conclude that tyre particles are hazardous pollutants of particular concern that are close to or possibly above chronic environmental safety limits in some locations.

Cardiac-induced motion of the pancreas and its effect on image quality of ultrahigh-resolution CT

Recent advancements in diagnostic CT detector technology have made it possible to resolve anatomical features smaller than 20 LP/cm, referred to as ultra-high-resolution (UHR) CT. Subtle biological motions that did not affect standard-resolution (SR) CT may not be neglected in UHR. This study aimed to quantify the cardiac-induced motion of the pancreas and simulate its impact on the image quality of UHR-CT. We measured the displacement of the head of the pancreas in three healthy volunteers using Displacement Encoding with Stimulated Echoes (DENSE) MRI. The results were used to simulate SR- and UHR-CT acquisitions affected by pancreatic motion.We found pancreatic displacement in the 0.24-1.59 mm range during one cardiac cycle across the subjects. The greatest displacement was observed in the anterior-posterior direction. The time to peak displacement varied across subjects. Both SR and UHR images showed reduced image quality, as measured by radial modulation transfer function, due to cardiac-induced motion, but the motion artifacts caused more severe degradation in UHR acquisitions. Our investigation of cardiac-induced pancreatic displacement reveals its potential to degrade both standard and UHR-CT scans. To fully utilize the improvement in spatial resolution offered by UHR-CT, the effects of cardiac-induced motion in the abdomen need to be understood and corrected.Relevance statement Advancements in CT detector technology have enhanced CT scanner spatial resolution to approximately 100 µm. Consequently, previously ignored biological motions such as the cardiac-induced motion of the pancreas now demand attention to fully utilize this improved resolution.

Trial Readiness of Cavernous Malformations With Symptomatic Hemorrhage, Part I: Event Rates and Clinical Outcome

BACKGROUND

Cerebral cavernous malformation with symptomatic hemorrhage (SH) are targets for novel therapies. A multisite trial-readiness project (https://www.clinicaltrials.gov; Unique identifier: NCT03652181) aimed to identify clinical, imaging, and functional changes in these patients.

METHODS

We enrolled adult cerebral cavernous malformation patients from 5 high-volume centers with SH within the prior year and no planned surgery. In addition to clinical and imaging review, we assessed baseline, 1- and 2-year National Institutes of Health Stroke Scale, modified Rankin Scale, European Quality of Life 5D-3 L, and patient-reported outcome-measurement information system, Version 2.0. SH and asymptomatic change rates were adjudicated. Changes in functional scores were assessed as a marker for hemorrhage.

RESULTS

One hundred twenty-three, 102, and 69 patients completed baseline, 1- and 2-year clinical assessments, respectively. There were 21 SH during 178.3 patient years of follow-up (11.8% per patient year). At baseline, 62.6% and 95.1% of patients had a modified Rankin Scale score of 1 and National Institutes of Health Stroke Scale score of 0 to 4, respectively, which improved to 75.4% (P=0.03) and 100% (P=0.06) at 2 years. At baseline, 74.8% had at least one abnormal patient-reported outcome-measurement information system, Version 2.0 domain compared with 61.2% at 2 years (P=0.004). The most common abnormal European Quality of Life 5D-3 L domains were pain (48.7%), anxiety (41.5%), and participation in usual activities (41.4%). Patients with prospective SH were more likely than those without SH to display functional decline in sleep, fatigue, and social function patient-reported outcome-measurement information system, Version 2.0 domains at 2 years. Other score changes did not differ significantly between groups at 2 years. The sensitivity of scores as an SH marker remained poor at the time interval assessed.

CONCLUSIONS

We report SH rate, functional, and patient-reported outcomes in trial-eligible cerebral cavernous malformation with SH patients. Functional outcomes and patient-reported outcomes generally improved over 2 years. No score change was highly sensitive or specific for SH and could not be used as a primary end point in a trial.

Prognostic Utility of Cardiovascular Magnetic Resonance-Based Phenotyping in Patients With Muscular Dystrophy

Background The prognostic utility of cardiovascular magnetic resonance imaging, including strain analysis and tissue characterization, has not been comprehensively investigated in adult patients with muscular dystrophy. Methods and Results We prospectively enrolled 148 patients with dystrophinopathies (including heterozygotes), limb-girdle muscular dystrophy, and type 1 myotonic dystrophy (median age, 36.0 [interquartile range, 23.0-50.0] years; 51 [34.5%] women) over 7.7 years in addition to an age- and sex-matched healthy control cohort (n=50). Cardiovascular magnetic resonance markers, including 3-dimensional strain and fibrosis, were assessed for their respective association with major adverse cardiac events. Our results showed that markers of contractile performance were reduced across all muscular dystrophy groups. In particular, the dystrophinopathies cohort experienced reduced left ventricular (LV) ejection fraction and high burden of replacement fibrosis. Patients with type 1 myotonic dystrophy showed a 26.8% relative reduction in LV mass with corresponding reduction in chamber volumes. Eighty-two major adverse cardiac events occurred over a median follow-up of 5.2 years. Although LV ejection fraction was significantly associated with major adverse cardiac events (adjusted hazard ratio [aHR], 3.0 [95% CI, 1.4-6.4]) after adjusting for covariates, peak 3-dimensional strain amplitude demonstrated greater predictive value (minimum principal amplitude: aHR, 5.5 [95% CI, 2.5-11.9]; maximum principal amplitude: aHR, 3.3 [95% CI, 1.6-6.8]; circumferential amplitude: aHR, 3.4 [95% CI, 1.6-7.2]; longitudinal amplitude: aHR, 3.4 [95% CI, 1.7-6.9]; and radial strain amplitude: aHR, 3.0 [95% CI, 1.4-6.1]). Minimum principal strain yielded incremental prognostic value beyond LV ejection fraction for association with major adverse cardiac events (change in χ2=13.8; P<0.001). Conclusions Cardiac dysfunction is observed across all muscular dystrophy subtypes; however, the subtypes demonstrate distinct phenotypic profiles. Myocardial deformation analysis highlights unique markers of principal strain that improve risk assessment over other strain markers, LV ejection fraction, and late gadolinium enhancement in this vulnerable patient population.

Tolfenamic Acid Derivatives: A New Class of Transcriptional Modulators with Potential Therapeutic Applications for Alzheimer's Disease and Related Disorders

The field of Alzheimer's disease (AD) has witnessed recent breakthroughs in the development of disease-modifying biologics and diagnostic markers. While immunotherapeutic interventions have provided much-awaited solutions, nucleic acid-based tools represent other avenues of intervention; however, these approaches are costly and invasive, and they have serious side effects. Previously, we have shown in AD animal models that tolfenamic acid (TA) can lower the expression of AD-related genes and their products and subsequently reduce pathological burden and improve cognition. Using TA as a scaffold and the zinc finger domain of SP1 as a pharmacophore, we developed safer and more potent brain-penetrating analogs that interfere with sequence-specific DNA binding at transcription start sites and predominantly modulate the expression of SP1 target genes. More importantly, the proteome of treated cells displayed ~75% of the downregulated products as SP1 targets. Specific levels of SP1-driven genes and AD biomarkers such as amyloid precursor protein (APP) and Tau proteins were also decreased as part of this targeted systemic response. These small molecules, therefore, offer a viable alternative to achieving desired therapeutic outcomes by interfering with both amyloid and Tau pathways with limited off-target systemic changes.

Comprehensive evaluations of a prototype full field-of-view photon counting CT system through phantom studies

Objective. Photon counting CT (PCCT) has been a research focus in the last two decades. Recent studies and advancements have demonstrated that systems using semiconductor-based photon counting detectors (PCDs) have the potential to provide better contrast, noise and spatial resolution performance compared to conventional scintillator-based systems. With multi-energy threshold detection, PCD can simultaneously provide the photon energy measurement and enable material decomposition for spectral imaging. In this work, we report a performance evaluation of our first CdZnTe-based prototype full-size PCCT system through various phantom imaging studies.Approach.This prototype system supports a 500 mm scan field-of-view and 10 mmz-coverage at isocenter. Phantom scans were acquired using 120 kVp from 50 to 400 mAs to assess the imaging performance on: CT number accuracy, uniformity, noise, spatial resolution, material differentiation and quantification.Main results.Both qualitative and quantitative evaluations show that PCCT, under the tested conditions, has superior imaging performance with lower noise and improved spatial resolution compared to conventional energy integrating detector (EID)-CT. Using projection domain material decomposition approach with multiple energy bin measurements, PCCT virtual monoenergetic images have lower noise, and good accuracy in quantifying iodine and calcium concentrations. These results lead to increased contrast-to-noise ratio (CNR) for both high and low contrast study objects compared to EID-CT at matched dose and spatial resolution. PCCT can also generate super-high resolution images using much smaller detector pixel size than EID-CT and greatly improve image spatial resolution.Significance.Improved spatial resolution and quantification accuracy with reduced image noise of the PCCT images can potentially lead to better diagnosis at reduced radiation dose compared to conventional EID-CT. Increased CNR achieved by PCCT suggests potential reduction in iodine contrast media load, resulting in better patient safety and reduced cost.

Cardiac Magnetic Resonance Imaging in Individuals With Prenatal Alcohol Exposure

Background

Prenatal alcohol exposure (PAE) has teratogenic effects on numerous body systems including the heart. However, research magnetic resonance imaging (MRI) studies in humans with PAE have thus far been limited to the brain. This study aims to use MRI to examine heart structure and function, brain volumes, and body composition in children and adolescents with PAE.

Methods

Heart, brain, and abdominal 3T MRI of 17 children, adolescents, and young adults with PAE and 53 unexposed controls was acquired to measure: (1) left ventricular ejection fraction, end-diastolic volume, end-systolic volume, stroke volume, cardiac output, longitudinal strain, circumferential strain, and heart mass; (2) total brain, cerebellum, white matter, grey matter, caudate, thalamus, putamen, and globus pallidus volumes; and (3) subcutaneous fat, visceral fat, muscle fat, and muscle (body composition).

Results

Cardiac MRI revealed no abnormalities in the PAE group on evaluation by a paediatric cardiologist and by statistical comparison with a control group. Cardiac parameters in both groups were in line with previous reports, including expected sex- and age-related differences. Cerebellum, caudate, and globus pallidus volumes were all smaller. Body mass index and subcutaneous fat percent were higher in females with PAE relative to control females, but lower in males with PAE relative to control males.

Conclusions

Children with PAE did not have abnormalities in MRI-derived measures of cardiac structure or function despite smaller brain volumes and sex-specific differences in body composition relative to healthy controls.

Regional Elevation of Liver T1 in Fontan Patients

Background

Fontan-associated liver disease (FALD) is characterized by hepatic congestion and progressive hepatic fibrosis in patients with the Fontan operation. This condition is generally clinically silent until late, necessitating techniques for early detection. Liver T1 mapping has been used to screen for FALD, but without consideration of regional variations in T1 values.

Methods

Liver T1 measured with a liver-specific T1 mapping sequence (PROFIT1) in Fontan patients was compared with cohorts of patients with biventricular congenital heart disease (BiV-CHD) and controls with normal cardiac function and anatomy.

Results

Liver T1 was significantly elevated in the Fontan cohort (n = 20) compared with patients with BiV-CHD (n = 12) and controls (n = 9) (781, 678, and 675 milliseconds, respectively; P < 0.001), with a consistent pattern of significantly elevated T1 values in the peripheral compared with central liver regions (ΔT1 = 54, 2, and 11 milliseconds; P < 0.001). PROFIT1 also yielded simultaneous T2∗ maps and fat fraction values that were similar in all groups. Fontan liver T1 values were also significantly elevated as compared with BiV-CHD and controls as measured with the cardiac (modified Look-Locker inversion) acquisitions (728, 583, and 583 milliseconds, respectively; P < 0.001) and values correlated with PROFIT1 liver T1 (R = 0.87, P < 0.001).

Conclusions

Fontan patients have globally increased liver T1 values and consistent spatial variations, with higher values in the peripheral liver regions as compared with spatially uniform values in BiV-CHD and controls. The spatial patterns may provide insight into the progression of FALD. Liver T1 mapping studies should include uniform spatial coverage to avoid bias based on slice locations in this population.

Time-Restricted Eating in Breast Cancer Survivors: Effects on Body Composition and Nutritional Status

In this secondary analysis of an 8-wk single-arm feasibility study of weekday time-restricted eating (TRE), we explored the effects of TRE on body composition. Women (n = 22; ≥60 yr) who had completed chemotherapy for early-stage breast cancer and had a body mass index ≥25 kg/m² were enrolled. Bioelectrical impedance analysis was performed before and after 8 wk of TRE, and nutritional status was evaluated by bioelectrical impedance vector analysis (BIVA). Body weight (p = 0.01) and total fat mass (p = 0.04) decreased with TRE. Phase angle was low (defined as ≤5.6°) in 86% of participants at baseline and did not change. Four participants who initially presented with obesity (>95% ellipse, BIVA) had favorable body composition modifications after TRE. Our study highlighted a less favorable body composition profile, poorer cell integrity and overhydration in these patients. BIVA was a useful method to assess body composition and hydration. A short TRE intervention was associated with decreased estimated fat mass and a favorable change in nutritional status in those with obesity.

H. pylori predictors and outcomes among adults undergoing upper endoscopy at a Jamaican teaching hospital: A cross-sectional study

BACKGROUND

Recent data on the prevalence of H. pylori infection in Jamaica are lacking. It is postulated that there has been a decline in the prevalence of H. pylori infection and its associated complications. We determined sociodemographic characteristics, prevalence of H. pylori infection and clinical outcomes among adults undergoing esophagogastroduodenoscopy (EGD) and histology at the University Hospital of the West Indies (UHWI) between May 2018 and December 2020.

MATERIALS AND METHODS

A cross-sectional study of patients (≥18 years old), who underwent EGD and histological evaluation for H. pylori infection, was conducted. Associations of H. pylori positivity and gastric cancer with sociodemographic/clinical variables and endoscopic findings were determined by stepwise logistic regression using backward selection. Unadjusted and adjusted odds ratios with related 95% confidence intervals (Cis) were calculated for H. pylori positivity and gastric cancer status.

RESULTS

There were 323 participants (mean age 58.6 ± 17.8 years, 54.2% females). H. pylori prevalence was 22.2% (n = 70 of 315), 5.6% had gastric neoplasia (GN), 15.5% gastric atrophy, 11.4% intestinal metaplasia and 3.7% dysplasia on histology. Mucositis (64.5%), gastric ulcer (14.9%), and duodenal ulcer (13.9%) were the most common endoscopic findings. Participants with peptic ulcer disease (PUD) (unOR = 4.0; p = .017), gastric cancer (unOR = 9.5; p = .003), gastric atrophy (unOR = 12.8; p < .001), and intestinal metaplasia (unOR = 5.0; p < .001) had a significantly higher odds of being H. pylori positive, but after multivariable analyses only gastric atrophy remained significant (aOR = 27.3; p < .001). Participants with mucositis had a significantly lower odds of gastric cancer (unOR 0.1; p = .035) while participants with dysplasia had significantly higher odds (unOR 8.0; p = .042), but these were no longer significant after multivariable analyses (aOR = 0.2; p = .156 and aOR = 18.9; p = .070, respectively).

CONCLUSIONS

Histology based prevalence of H. pylori infection is lower than previously reported in Jamaica. Gastric atrophy is a significant predictor of H. pylori positivity.

Abstract WP121: Can The Extended Glasgow Outcome Scale (e-gos) Augment The Interpretation Of Results From Clinical Trials Of Minimally Invasive Surgery Of Spontaneous Intracerebral Hemorrhage Using The Modified Rankin Scale (mrs): A Secondary Analysis Of The Clear-iii And Mistie-iii Trials

Introduction: Currently, the modified Rankin scale (mRS) is most commonly used to assess functional outcome in clinical trials of interventions for spontaneous intracerebral hemorrhage (ICH). Extended Glasgow Outcome Score (eGOS) is often used to assess global disability/recovery after traumatic brain injury and provides additional discrimination of vegetative state (VS) from lower severe disability (LSD). We compared primary outcomes from 2 clinical trials of minimally invasive surgery for intracerebral and intraventricular hemorrhage (ICH/IVH) at different thresholds of eGOS.

Methods: Post-hoc analysis of primary outcomes (PO) from the CLEAR-III trial (intraventricular alteplase [IVtPA] vs. saline for obstructive IVH; N=500; PO: mRS 0-3 at day 180), and MISTIE-III trial (stereotactic thrombolysis [MIS+tPA] vs. conservative management; N=499; PO: mRS 0-3 at day 365). eGOS was derived from functional outcome scales obtained during the trials. Outcomes on eGOS were categorized into 5 subgroups: good outcomes: 7-8 (A), 5-6 (B), 4 (C), and poor outcomes: 3 (D), and 1-2 (E). Generalized, ordered logistic regression analysis was performed, adjusting for age, ICH location, stability ICH and IVH volumes, and randomization GCS.

Results: eGOS scales were available in 481 (96%) patients at day 180 in CLEAR-III and 478 (96%) patients at day 365 in MISTIE-III. In CLEAR-III, odds of being in eGOS category D (LSD) or E (death or VS) vs. the others, were approximately 40% lower for IVtPA group compared to saline group (aOR = 0.59; 95% CI, 0.38-0.90; p=0.016), and odds of being in category E (vs. the others) were almost 50% lower (aOR = 0.51; 95% CI, 0.33-0.80; p=0.004). VS occurred in 2.49% of IVtPA and 2.07% of saline group patients. In MISTIE-III, odds of being in eGOS category D or E (vs. the others) were not significantly different for MIS+tPA vs. conservative treatment: aOR = 0.84; 95% CI, 0.55-1.28; p=0.41), as were odds for being in eGOS category E (vs. the others), aOR = 0.77; 95% CI, 0.48-1.24; p=0.29).

Conclusions: The 5-category dichotomized eGOS (4-8 vs. 1-3) defines a functional outcome improvement in CLEAR-III at day 180, which was not observed using the PO with mRS. Use of eGOS did not result in a different interpretation of the MISTIE-III trial.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease

BACKGROUND AND AIMS

Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis.

APPROACH AND RESULTS

A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS.

CONCLUSIONS

Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Abstract 121: Prospective Symptomatic Hemorrhage Rates And Functional Outcomes In Trial Eligible Cavernous Angiomas With Symptomatic Hemorrhage

Background: Cerebral cavernous angiomas with symptomatic hemorrhage (CASH) carry highest rebleed rates and are targeted for novel interventions. A multisite clinical trial readiness project (clinicaltrials.gov NCT03652181) aims to identify clinical and functional changes over time in trial eligible CASH patients.

Methods: Adult patients from 5 high volume centers with a CASH in the prior year and no planned surgical intervention were enrolled. In addition to demographic, clinical, and imaging review, patients underwent baseline, 1 year and 2 year NIH-stroke scale (NIHSS), modified Rankin scale (mRS), Euro-QOL 5D-3L (EQ-5D-3L) and EQ VAS (visual analog score), and PROMIS 29 assessments. Recurrent symptomatic hemorrhages (SH) were verified. We assessed the hemorrhage rate, change in scores/scales over time, and determined which scales/scores were most affected in patients with SH.

Results: 123 patients completed baseline assessments and were prospectively followed (60.9% female; mean age 44.1 years; 39.1% familial; 41.5% brainstem location). As of reporting date, 89 of 104 (86%) and 58 of 76 (76%) cases have completed assessments. There were 16 SHs during 147 patient-years of follow up (10.9% per patient year). At baseline, 111 (90.2%) of patients had NIHSS 0-2 and 77 (62.6%) patients had mRS baseline 0-1 which improved to 40 (95.2 %) and 43 (75.4%) at 2 years. At baseline, 54 (43.9%) of patients had at least one moderate to severely abnormal PROMIS-29 domain compared to 13 (26.5%) at 2 years. EQ-5D-3L baseline demonstrated a moderate proportion of patients reporting some difficulty with pain (48.8%), anxiety (41.5%), and activity (41.5%) which improved to 28%, 30%, and 34% respectively at 2 years. Patients with a prospective SH were more likely than those without recurrent SH at 2 years to display mild functional decline (0.5 SD) of most PROMIS-29 domains, a mRS of 2 or higher and an abnormal EQ- self-care (P<0.05). Other scales/scores were not significantly different between the groups.

Conclusion: We report SH rate and functional outcome at baseline and rates of changes during 2 years in trial eligible CASH patients. The PROMIS-29, mRS, and EQ-self-care domains were most discriminative in patients with recurrent SH. No test was 100% specific.

The transcriptional co-regulators NBCL1 and NBCL2 redundantly coordinate aerial organ development and root nodule identity in legumes

Medicago truncatula NODULE ROOT1 (MtNOOT1) and Pisum sativum COCHLEATA1 (PsCOCH1) are orthologous genes belonging to the NOOT-BOP-COCH-LIKE (NBCL) gene family which encodes key transcriptional co-regulators of plant development. In Mtnoot1 and Pscoch1 mutants, the development of stipules, flowers, and symbiotic nodules is altered. MtNOOT2 and PsCOCH2 represent the single paralogues of MtNOOT1 and PsCOCH1, respectively. In M. truncatula, MtNOOT1 and MtNOOT2 are both required for the establishment and maintenance of symbiotic nodule identity. In legumes, the role of NBCL2 in above-ground development is not known. To better understand the roles of NBCL genes in legumes, we used M. truncatula and P. sativum nbcl mutants, isolated a knockout mutant for the PsCOCH2 locus and generated Pscoch1coch2 double mutants in P. sativum. Our work shows that single Mtnoot2 and Pscoch2 mutants develop wild-type stipules, flowers, and symbiotic nodules. However, the number of flowers was increased and the pods and seeds were smaller compared to the wild type. Furthermore, in comparison to the corresponding nbcl1 single mutants, both the M. truncatula and P. sativum nbcl double mutants show a drastic alteration in stipule, inflorescence, flower, and nodule development. Remarkably, in both M. truncatula and P. sativum nbcl double mutants, stipules are transformed into a range of aberrant leaf-like structures.

Detection and characterisation of microplastics and microfibres in fishmeal and soybean meal

Aquaculture is an increasingly important source of nutrition for global food security, which is reliant on animal- and plant-based feeds. Anthropogenic particles, including microplastics and semi-synthetic cellulosic fibres, are prolific marine pollutants that are readily consumed by marine organisms, including small pelagic fish commonly used in fishmeal. Conversely, there is no indication plants can accumulate anthropogenic microparticles. We explore whether aquaculture feed presents a route of contamination for farmed fish. Commercially-sourced aquaculture feedstocks, including fishmeals and soybean meal, were processed (KOH digestion and ZnCl₂ density separation) and anthropogenic particles characterised using microscopy and spectroscopic methods. Both fishmeal and soybean meals contained anthropogenic particles, with concentrations ranging 1070-2000 particles kg^-1. The prevalence of anthropogenic particles in plant-based feeds indicates that the majority of contamination occurs post-harvest. Based on our findings, farmed Atlantic salmon may be exposed to a minimum of 1788-3013 anthropogenic particles from aquaculture feed across their commercial lifespan.

Neglect in Childhood, Problem Behavior in Adulthood

Few studies have reported problem behaviors in adulthood related to the timing of child neglect. The objective was to examine the relationship between classes of child neglect and later behavior. The sample included 473 participants from the prospective Longitudinal Studies of Child Abuse and Neglect (LONGSCAN); their mean age was 23.8 years. They completed an online survey regarding behaviors and experiences in early adulthood. Neglect was assessed via Child Protective Services (CPS) and self-reports of neglect. Latent class analysis (LCA) identified three classes: Late Neglect, Chronic Neglect, and Limited Neglect. There were significant differences between Limited and Late Neglect regarding later intimate partner aggression and violence (IPAV) and psychological distress, and among all classes for criminal behavior. High-risk youth experiencing neglect beginning in mid-adolescence appear especially vulnerable to later criminal behavior, psychological distress, and IPAV. Those working with such youth can help ensure that their needs are adequately met, to prevent or mitigate problems in adulthood.

Risk of variceal hemorrhage and pretransplant mortality in children with biliary atresia

BACKGROUND AND AIMS

The natural history of gastroesophageal variceal hemorrhage (VH) in biliary atresia (BA) is not well characterized. We analyzed risk factors, incidence, and outcomes of VH in a longitudinal multicenter study.

APPROACH AND RESULTS

Participants enrolled in either an incident (Prospective Database of Infants with Cholestasis [PROBE]) or prevalent (Biliary Atresia Study of Infants and Children [BASIC]) cohort of BA were included. Variceal hemorrhage (VH) was defined based on gastrointestinal bleeding in the presence of varices accompanied by endoscopic or nontransplant surgical intervention. Cumulative incidence of VH and transplant-free survival was compared based on features of portal hypertension (e.g., splenomegaly, thrombocytopenia) and clinical parameters at baseline in each cohort (PROBE: 1.5 to 4.5 months after hepatoportoenterostomy [HPE]; BASIC: at enrollment > 3 years of age). Analyses were conducted on 869 children with BA enrolled between June 2004 and December 2020 (521 in PROBE [262 (51%) with a functioning HPE] and 348 in BASIC). The overall incidence of first observed VH at 5 years was 9.4% (95% CI: 7.0-12.4) in PROBE and 8.0% (5.2-11.5) in BASIC. Features of portal hypertension, platelet count, total bilirubin, aspartate aminotransferase (AST), albumin, and AST-to-platelet ratio index at baseline were associated with an increased risk of subsequent VH in both cohorts. Transplant-free survival at 5 years was 45.1% (40.5-49.6) in PROBE and 79.2% (74.1-83.4) in BASIC. Two (2.5%) of 80 participants who had VH died, whereas 10 (12.5%) underwent transplant within 6 weeks of VH.

CONCLUSIONS

The low risk of VH and associated mortality in children with BA needs to be considered in decisions related to screening for varices and primary prophylaxis of VH.

770 Determining the Diagnostic Value of an Abdominal Ultrasound in Women Presenting with Right Iliac Fossa Pain in an Acute Surgical Unit

Aim

Right iliac fossa (RIF) pain is a common acute surgical presentation, with appendicitis being the main differential diagnosis. In women of childbearing age, abdominal and pelvic ultrasounds (USS) are often the imaging modality of choice and can be particularly useful when the diagnosis is unclear. We aimed to determine the diagnostic value of USS in patients of childbearing age, presenting with RIF pain.

Method

A single centre retrospective review, of women aged 14 to 45 years old, presenting with RIF pain and undergoing a subsequent USS, over a 6-month period. Investigation results, length of stay, white cell count (WCC) and C-reactive protein on admission, and treatment outcomes were all recorded.

Results

45 consecutive patients were reviewed, with a median age of 28 years (14–45). 37 USS were reported as normal and 8 illustrated gynaecological pathology. None could confirm appendicitis. 24 patients had a normal WCC and a CRP of &lt;5 on admission, none of which had radiological findings requiring surgical intervention. 3 did progress to laparoscopic appendicectomy, 66.6% of which returned with negative pathology. Conservatively managed patients, with a normal USS and normal inflammatory markers, accrued a combined hospital stay of 53 days.

Conclusion

Our results illustrate that in patients with RIF pain and normal inflammatory markers, an USS is unlikely to demonstrate pathology requiring surgical intervention and therefore is of limited positive diagnostic value. However, a negative USS may aid patient reassurance and facilitate earlier discharge in this cohort.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Global variation in early epidemic growth rates and reproduction number of seasonal influenza

INTRODUCTION

Little is known about global variation in early epidemic growth rates and effective reproduction numbers (R_e) of seasonal influenza. We aimed to estimate global variation in R_e of influenza type A and B during a single period.

METHODS

Country influenza detection time series from September 2017 through January 2019 were obtained from an international database. Type A and B epidemics by country were selected based on R_e estimates for a five-week moving window advanced by week. Associations of R_e with absolute latitude, Human Development Index, percent of the population aged <15 years and percent living rurally in each country were assessed.

RESULTS

Time series were included for 119 of 169 available countries. There were 100 countries with influenza A and 79 with B epidemics. Median R_e for both influenza A and B epidemics was 1.23 (ranges: A 1.10, 1.60; B 1.06, 1.58). R_e of influenza B, but not A, was independently associated with absolute latitude, increasing by 0.022 (95% CI 0.002, 0.043) per 10 degrees.

CONCLUSIONS

R_e of influenza A and B were similar. Only R_e of influenza B was associated with country characteristics; increasing with distance from the equator. The approach may be suitable for continuous R_e surveillance.

Myocardial Iron Deficiency and Mitochondrial Dysfunction in Advanced Heart Failure in Humans

Background

Myocardial iron deficiency (MID) in heart failure (HF) remains largely unexplored. We aim to establish defining criterion for MID, evaluate its pathophysiological role, and evaluate the applicability of monitoring it non‐invasively in human explanted hearts.

Methods and Results

Biventricular tissue iron levels were measured in both failing (n=138) and non‐failing control (NFC, n=46) explanted human hearts. Clinical phenotyping was complemented with comprehensive assessment of myocardial remodeling and mitochondrial functional profiles, including metabolic and oxidative stress. Myocardial iron status was further investigated by cardiac magnetic resonance imaging. Myocardial iron content in the left ventricle was lower in HF versus NFC (121.4 [88.1–150.3] versus 137.4 [109.2–165.9] μg/g dry weight), which was absent in the right ventricle. With a priori cutoff of 86.1 μg/g d.w. in left ventricle, we identified 23% of HF patients with MID (HF‐MID) associated with higher NYHA class and worsened left ventricle function. Respiratory chain and Krebs cycle enzymatic activities were suppressed and strongly correlated with depleted iron stores in HF‐MID hearts. Defenses against oxidative stress were severely impaired in association with worsened adverse remodeling in iron‐deficient hearts. Mechanistically, iron uptake pathways were impeded in HF‐MID including decreased translocation to the sarcolemma, while transmembrane fraction of ferroportin positively correlated with MID. Cardiac magnetic resonance with T2* effectively captured myocardial iron levels in failing hearts.

Conclusions

MID is highly prevalent in advanced human HF and exacerbates pathological remodeling in HF driven primarily by dysfunctional mitochondria and increased oxidative stress in the left ventricle. Cardiac magnetic resonance demonstrates clinical potential to non‐invasively monitor MID.

Outcomes After Laparoscopic Transabdominal Pre-Peritoneal Repair (TAPP) For Groin Hernia In A Single Consultant Series

AIM

TAPP repair is an established minimally invasive approach for groin hernia repair. The objective of this study was to report post-operative outcomes after TAPP repair in a single surgeon series and benchmark these against reported outcomes in the literature.

METHODS

All patients who had an elective or emergency TAPP repair of a groin hernia from September 2016 to March 2020 in a district general hospital were retrospectively analysed from the electronic care record (ECR) for post-operative morbidity, re-admission, recurrence and length of hospital stay. The primary outcome of interest, chronic post-operative pain, was assessed via telephone interviews using the European Registry for Abdominal Wall Hernias Quality of Life (EuraHS-QoL) questionnaire.

RESULTS

164 patients, incorporating 190 hernia repairs were included. 155 (94.5%) were men and 9 (5.5%) were women. The median age was 51 (range: 20-81). 160 (97.6%) patients had an elective repair and 4 (2.4%) had an emergency repair. 157 (95.7%) patients underwent a primary inguinal hernia repair, of which 26 (15.8%) had a bilateral inguinal hernia repair. 7 (4.3%) patients had a femoral hernia repair. All procedures were performed by a single consultant surgeon. One emergency patient required conversion to open to allow for resection of ischaemic small bowel, however, the hernia itself was repaired laparoscopically. 94 (57.3%) patients were successfully contacted to provide EuraHS-QoL scores. 13/94 patients (13.8%) complained of chronic pain at rest on an average follow-up of 32.7 months (range: 16-43m). 2/94 (2.1%) patients had mild pain, 9/94 (9.6%) had moderate pain and 2/94 (2.1%) patients had severe pain at rest. 131 (79.9%) TAPP repairs were performed as day case procedures. Median length of stay in those patients who were not day cases was 1 day (range=1-11 days). Post-op morbidity rate was 7.9% (n=13), however, these were minor complications (Clavien-Dindo I/II). Incidence of seroma and haematoma was 1.8% (n=3) each. Re-admission rate was 3% (n=5). Mean follow-up of patients was 21 months (SD 12.6m, range=1-43m). Two patients (1.2%) had a recurrent groin hernia during this time period and one patient (0.6%) had a port site hernia.

CONCLUSION

The outcomes of chronic post-operative pain and rate of recurrence were comparable to those reported in the literature. Re-admission rate was low and there were no major complications. The majority of patients were performed as a day case.

Cardiac Stroke Volume Index Is Associated With Early Neurological Improvement in Acute Ischemic Stroke Patients

Early neurological improvement as assessed with the NIH stroke scale (NIHSS) at 24 h has been associated with improved long-term functional outcomes following acute ischemic stroke (AIS). Cardiac dysfunction is often present in AIS, but its association with outcomes is incompletely defined. We performed a pilot study to evaluate the association between non-invasively measured cardiac parameters and 24-h neurological improvement in prospectively enrolled patients with suspected AIS who presented within 12 h of symptom-onset and had an initial systolic blood pressure>140 mm Hg. Patients receiving thrombolytic therapy or mechanical thrombectomy were excluded. Non-invasive pulse contour analysis was used to measure mean arterial blood pressure (MAP), cardiac stroke volume index (cSVI), cardiac output (CO) and cardiac index (CI). Transcranial Doppler recorded mean middle cerebral artery flow velocity (MFV). We defined a decrease of 4 NIHSS points or NIHSS ≤ 1 at 24-h as neurological improvement. Of 75 suspected, 38 had confirmed AIS and did not receive reperfusion therapy. Of these, 7/38 (18.4%) had neurological improvement over 24 h. MAP was greater in those without improvement (108, IQR 96-123 mm Hg) vs. those with (89, IQR 73-104 mm Hg). cSVI, CO, and MFV were similar between those without and with improvement: 37.4 (IQR 30.9-47.7) vs. 44.7 (IQR 42.3-55.3) ml/m2; 5.2 (IQR 4.2-6.6) vs. 5.3 (IQR 4.7-6.7) mL/min; and 39.9 (IQR 32.1-45.7) vs. 34.4 (IQR 27.1-49.2) cm/s, respectively. Multivariate analysis found MAP and cSVI as predictors for improvement (OR 0.93, 95%CI 0.85-0.98 and 1.14, 95%CI 1.03-1.31). In this pilot study, cSVI and MAP were associated with 24-h neurological improvement in AIS.

Experiences of UK African-Caribbean prostate cancer survivors of discharge to primary care

Objective: Black men are three times more likely to develop prostate cancer (PCa), to do so at a younger age and to experience a more aggressive form than White men. This study aims to understand the experiences of African-Caribbean men with respect to their discharge to primary care following successful PCa treatment and the challenges associated with survivorship.Design: Eight African-Caribbean men, who had been successfully treated for PCa, were recruited through the charity BME Cancer Communities. They participated in a focus group, which took place on the premises of the charity and was audio-recorded. The recording was transcribed and the data were analysed employing thematic analysis.Results: Three overarching themes were developed: Discharge - misconceptions and uncertainties; Survivorship - challenges and ways of coping; Black men and PCa: real and potential discrimination. Participants expressed concerns regarding the lack of information and clarity about what discharge meant, the quality of follow-up care, especially the levels of specialist knowledge among GPs, and the impact of side-effects, particularly erectile dysfunction (ED). Participants linked ED with stereotypes of Black male sexuality, particularly in relation to difficulties of expressing their emotions and psychological distress. African-Caribbean men face particular challenges in dealing with the side-effects of treatment for PCa, which are linked to socially-constructed ideas of masculinity.Conclusion: There needs to be a greater focus in primary care on understanding these issues and providing individualised culturally-sensitive care. In particular, GPs should be aware of sensitivities concerning help-seeking related to culturally-mediated understandings of masculinity.

Tuning the Bulk and Surface Properties of PDMS Networks through Cross-Linker and Surfactant Concentration

The elastic modulus and hydrophilicity of cross-linked poly(dimethylsiloxane) (PDMS) are tunable via cross-linker concentration and the addition of a simple surfactant, C12E4, before curing. However, the surfactant concentration, [C12E4], reduces the elastic modulus (73% lower for 6.3% w/w) because it reduces the extent of curing. This is likely because the hygroscopic surfactant results in water poisoning of the catalyst. Three distinct time-dependent hydrophilicity profiles were identified using water contact angle analysis with [C12E4] determining which profile was observed. This indicates the concentration-dependent phase behavior of C12E4 within PDMS films. Changes in phase behavior were identified using small-angle neutron scattering (SANS) and a compatibility study. No surface excess or surface segregation of surfactant was observed at the PDMS-air interface. However, a surface excess revealed by neutron reflectivity against a D2O interface indicates that the increase in hydrophilicity results from the migration of C12E4 to the film interface when exposed to water.

The Association between GDP and non-communicable disease mortality in the WHO European Region

Background

The WHO Europe Region consists of 53 countries, each of which has differences in mortality from cardiovascular (CVD), neurological, and chronic respiratory diseases. Such diverse metrics result from political, social, and economic events that have influenced the health performance of each European sub-region. From a public health perspective, an updated analysis of such metrics is required for policymakers and health system organisations to improve the overall population health outcomes.

Methods

This study utilised data between 1990-2017 from the Global Burden of Disease study 2017 to explore the association between GDP and NCD mortality in Western, Central, and Eastern Europe and Central Asia. The mortality data was already stratified by age and sex, and a fixed effected regression analysis was run to observe associations between both variables using STATA. Data completeness was 80-100% for GDP and 100% for mortality across the European region. The final results were reported as a rate per 100,000, with confidence intervals. The rate changes were calculated using an equation from the GBD.

Results

The most significant decrease per 100,000 of the population across all three NCDs as GDP increased was in Central Asia and Eastern Europe among both sexes. For every 1000 unit increase in GDP, we expect -12.13 [-13.60, -10.66] and -14.49 [-16.89, -12.29] less deaths in CVD in females and males per 100,000 of population, respectively. Western Europe had the lowest decrease per 100,000 of the population, as with every 1000 unit increase in GDP, we expect -2.42 [-2.59, -2.25] and -4.09 [-4.33, -3.84] fewer deaths in CVD in females and males, respectively.

Conclusions

The overall differential rate of mortality from the three NCDs is decreasing across all regions. However, there is a large disparity between the sexes. Males have a higher mortality rate across CVD and chronic respiratory diseases, whilst neurological disorders were highest among females.

Key messages

This study’s analysis has added to existing knowledge on chronic health patterns in the WHO European region. Governments in Eastern Europe and Central Asia should introduce health policies targeting unhealthy consumption of alcohol, smoking and diets, as seen in Western Europe.

Human Leukocyte Antigen Profile Predicts Severity of Autoimmune Liver Disease in Children of European Ancestry

BACKGROUND AND AIMS

Genetic predisposition to autoimmune hepatitis (AIH) in adults is associated with possession of human leukocyte antigen (HLA) class I (A*01, B*08) and class II (DRB1*03, -04, -07, or -13) alleles, depending on geographic region. Juvenile autoimmune liver disease (AILD) comprises AIH-1, AIH-2, and autoimmune sclerosing cholangitis (ASC), which are phenotypically different from their adult counterparts. We aimed to define the relationship between HLA profile and disease course, severity, and outcome in juvenile AILD.

APPROACH AND RESULTS

We studied 236 children of European ancestry (152 female [64%], median age 11.15 years, range 0.8-17), including 100 with AIH-1, 59 with AIH-2, and 77 with ASC. The follow-up period was from 1977 to June 2019 (median 14.5 years). Class I and II HLA genotyping was performed using PCR/sequence-specific primers. HLA B*08, -DRB1*03, and the A1-B8-DR3 haplotype impart predisposition to all three forms of AILD. Homozygosity for DRB1*03 represented the strongest risk factor (8.8). HLA DRB1*04, which independently confers susceptibility to AIH in adults, was infrequent in AIH-1 and ASC, suggesting protection; and DRB1*15 (DR15) was protective against all forms of AILD. Distinct HLA class II alleles predispose to the different subgroups of juvenile AILD: DRB1*03 to AIH-1, DRB1*13 to ASC, and DRB1*07 to AIH-2. Possession of homozygous DRB1*03 or of DRB1*13 is associated with fibrosis at disease onset, and possession of these two genes in addition to DRB1*07 is associated with a more severe disease in all three subgroups.

CONCLUSIONS

Unique HLA profiles are seen in each subgroup of juvenile AILD. HLA genotype might be useful in predicting responsiveness to immunosuppressive treatment and course.

β-Amyrin Synthase1 Controls the Accumulation of the Major Saponins Present in Pea (Pisum sativum)

The use of pulses as ingredients for the production of food products rich in plant proteins is increasing. However, protein fractions prepared from pea or other pulses contain significant amounts of saponins, glycosylated triterpenes that can impart an undesirable bitter taste when used as an ingredient in foodstuffs. In this article, we describe the identification and characterization of a gene involved in saponin biosynthesis during pea seed development, by screening mutants obtained from two Pisum sativum TILLING (Targeting Induced Local Lesions IN Genomes) populations in two different genetic backgrounds. The mutations studied are located in a gene designated PsBAS1 (β-amyrin synthase1), which is highly expressed in maturing pea seeds and which encodes a protein previously shown to correspond to an active β-amyrin synthase. The first allele is a nonsense mutation, while the second mutation is located in a splice site and gives rise to a mis-spliced transcript encoding a truncated, nonfunctional protein. The homozygous mutant seeds accumulated virtually no saponin without affecting the seed nutritional or physiological quality. Interestingly, BAS1 appears to control saponin accumulation in all other tissues of the plant examined. These lines represent a first step in the development of pea varieties lacking bitterness off-flavors in their seeds. Our work also shows that TILLING populations in different genetic backgrounds represent valuable genetic resources for both crop improvement and functional genomics.

Remote ischaemic conditioning in ST elevation myocardial infarction: a registry-based randomised trial

OBJECTIVES

Remote ischaemic conditioning (RIC) has been tested as a possible strategy for mitigating reperfusion injury in ST elevation myocardial infarction (STEMI) with primary percutaneous coronary intervention (PPCI). However, surrogate outcomes have shown inconsistent effects with lack of clinical correlation.

METHODS

We performed a registry-based randomised study of patients with STEMI allocated to RIC (4 cycles of blood pressure cuff inflation to 200 mm Hg for 5 min of ischaemia followed by 5 min of reperfusion) or standard of care (SOC) during PPCI. We examined the associations of RIC on core laboratory measurements of myocardial perfusion, infarct size (IS), left ventricular (LV) performance and clinical outcomes.

RESULTS

A total of 252 patients were enrolled. The median age was 61 (IQR: 55-70) years and 72.8% were male. Sum ST segment deviation resolution ≥50% was similar between RIC and SOC (65.2% vs 55.7%, p=0.269). In those with 3-day cardiovascular MRI (n=88), no difference in median (25th, 75th percentiles) IS (14.9% (4.5%, 23.1%) vs 16.1% (3.3%, 22.0%), p=0.980), LV dimensions (LV end-diastolic volume index: 78.7 (71.1, 91.2) mL/m² vs 79.9 (71.2, 88.8) mL/m², p=0.630; LV end-systolic volume index: 48.8 (35.7, 51.4) mL/m² vs 37.9 (31.8, 47.5) mL/m², p=0.551) or ejection fraction (50.0% (41.0%-55.0%) vs 50.0% (43.0%-56.0%), p=0.554) was demonstrated. Similar results were observed with 90-day cardiovascular MRI. At 1 year, the clinical composite of death, congestive heart failure, cardiogenic shock and recurrent myocardial infarction was similar in RIC and SOC (21.7% vs 13.3%, p=0.110).

CONCLUSIONS

In a contemporary registry-based randomised study of patients with STEMI undergoing PPCI, adjunctive therapy with RIC did not improve myocardial perfusion, reduce IS or alter LV performance. Consequently, there was no difference in clinical outcomes within 1 year.

TRIAL REGISTRATION NUMBER

NCT03930589.

Sub-organism (acetylcholinesterase activity), population (survival) and chemical concentration responses reinforce mechanisms of antagonism associated with malathion toxicity

Within human modified ecosystems the effects of individual stressors are difficult to establish amid co-occurring biological processes, environmental gradients and other stressors. Coupled examination of several endpoints across different levels of organisation may help elucidate the individual and combined effects of stressors and interactions. Malathion is a commonly used organophosphate pesticide that contaminates freshwaters and has strong negative effects on aquatic biota. However, both other stressors (e.g. increased sediment) and common ecosystem components (e.g. macrophytes and variable pH) can reduce the aqueous concentrations of malathion, reducing its toxic effects. We conducted a fully orthogonal bioassay to examine how pH (at 7 and 7.8) and sorptive processes (across two levels of kaoline clay 0 and 24 g L^-1) affected aqueous malathion concentrations and toxicity in an aquatic invertebrate genus. Survival and acetylcholinesterase activity as a sub-organism response were examined in the mayfly Coloburiscoides spp. (Ephemeroptera; Coluburiscidae). Measured aqueous malathion concentrations decreased with increased pH and in the presence of kaolin clay. Survival declined with increasing malathion concentrations and exposure period. Results further identify that antagonism of malathion toxicity was associated with both pH (alkaline hydrolysis) and effects associated with sediment independent of pH (driven by sorptive processes). However, model predictions varied associated with target and measured concentrations and concentrations examined. Antagonistic effects were most apparent using subset target malathion concentrations because of the dominant effect of malathion at high concentrations. Acetylcholinesterase activity, identified repression occurred across all treatments and did not identify antagonistic interactions, but these results were similar to survival responses at the time points examined (i.e. 120 h). Examination of chemistry, acetylcholinesterase, and survival, affords greater understanding of stressor effects and their interactions. Measured malathion concentrations may underestimate effects on aquatic biota; not because of synergism among stressors, but because of strong effects despite antagonism.

Tailor-made recombinant prokaryotic lectins for characterisation of glycoproteins

Development of biosimilars is costly, where glycan analysis is a significant constraint on time and money. This paper provides an in-depth characterisation of several novel recombinant prokaryotic lectins (RPLs), developed through directed evolution, displaying specific binding activities to α-mannose, β-galactose, fucose and sialic acid residues, tested against major biosimilar targets. The binding characterisation of all lectins was performed employing the principles of bio-layer interferometry (BLI), with help of the streptavidin-coated sensor with the biotinylated lectins. The binding activity of the RPLs and the specificity to a broad range of glycoproteins and glycoconjugates were evaluated and compared to those of equivalent plant-derived lectins. While exhibiting better or similar specificity, RPLs displayed significantly better binding in all cases. The binding mechanisms are explained with particular focus on the role hydrogen bonding plays in the change of specificity for a galactose specific lectin. Furthermore, different sets of RPLs and their plant equivalents were assayed against the different glycoprotein targets to evaluate the analytical parameters of the lectin-glycoprotein interaction. The obtained LoDs reached by the RPLs were lower than those of their plant counterparts apart from one, exhibiting RPL:PL LoD ratios of 0.8, 2.5, 14.2 and 380 for the sets of lectins specific to fucose, α-mannose, β-galactose and sialic acid, respectively. Such enhancement in analytical parameters of RPLs shows their applicability in protein purification and as bioanalytical tools for glycan analysis and biosensor development.

Abstract P46: Baseline Characteristics of Patients With Cerebral Cavernous Angiomas With Symptomatic Hemorrhage in a Multisite Trial Readiness Study

Background: Patients with cerebral cavernous angiomas with symptomatic hemorrhage (CASH) have high risk of disability from recurrent bleeding. Candidate medications to prevent rebleeding in CASH lesions will require multisite clinical trials with standardized data collection.

Objective: To report the prevalence and baseline cohort features in CASH patients and establish a research network infrastructure for trials.

Methods: This prospective observational cohort study includes adults with radiologically verified CASH lesion within 1-year of consent. Exclusions include prior or planned surgical intervention, spinal location, or prior brain irradiation. Six sites enrolled patients into the screening and clinical assessment portion of the study starting July 2018. Patients also had the option to participate in the follow up biomarker validation at 4 sites. Baseline demographics, clinical and imaging information, and outcomes (mRS, PROMIS-29, NIHSS, and EuroQol-5D) were collected. Biomarker imaging included dynamic contrast enhanced quantitative perfusion (DCEQP) and quantitative susceptibility mapping (QSM) that correlated with symptomatic bleeding. Descriptive statistics were performed and one-sample t-test was used to compare whether mean T-scores for PROMIS-29 domains differed significantly from a reference population.

Results: As of May 2020, 849 CASH patients were screened of whom 110 (13%) were eligible and enrolled; 73 also enrolled into the biomarker validation study. Average age at enrollment was 46±16 years at a mean of 4.4 months after symptom onset; 53% were female, 41% were familial, and 43% of CASH lesions were brainstem location. At enrollment, 90% of the cohort had independent functional outcome (mRS ≤ 2 and NIHSS <5). Perceived health problems affecting QoL were reported in >30% (EuroQol-5D). CASH cases had significantly worse anxiety but better depression and social satisfaction scores compared to a general population (all P<0.01). Baseline DCEQP and QSM measures did not differ significantly across sites.

Conclusion: We demonstrate feasibility of multisite recruitment of CASH patients and report prevalence of baseline features that will aid in design of clinical trials and inclusion of appropriate outcome measures.

Gilbert Kymer: Rector of the first conjoint medical college

Dr Gilbert Kymer (d. 1463) was a leading royal physician, scholar, cleric and university administrator of the first half of the 15th century. He was physician to Henry V & VI, and principally to Humphrey Duke of Gloucester, for whom he wrote an extensive Dietarium. He collected medical books and facilitated their translation, and helped to set up Duke Humfrey's library at Oxford. He became Dean of Salisbury, and for 11 years was Chancellor of the University of Oxford.

Targeted Therapies for Metabolic Myopathies Related to Glycogen Storage and Lipid Metabolism: a Systematic Review and Steps Towards a 'Treatabolome'

BACKGROUND

Metabolic myopathies are a heterogenous group of muscle diseases typically characterized by exercise intolerance, myalgia and progressive muscle weakness. Effective treatments for some of these diseases are available, but while our understanding of the pathogenesis of metabolic myopathies related to glycogen storage, lipid metabolism and β-oxidation is well established, evidence linking treatments with the precise causative genetic defect is lacking.

OBJECTIVE

The objective of this study was to collate all published evidence on pharmacological therapies for the aforementioned metabolic myopathies and link this to the genetic mutation in a format amenable to databasing for further computational use in line with the principles of the "treatabolome" project.

METHODS

A systematic literature review was conducted to retrieve all levels of evidence examining the therapeutic efficacy of pharmacological treatments on metabolic myopathies related to glycogen storage and lipid metabolism. A key inclusion criterion was the availability of the genetic variant of the treated patients in order to link treatment outcome with the genetic defect.

RESULTS

Of the 1,085 articles initially identified, 268 full-text articles were assessed for eligibility, of which 87 were carried over into the final data extraction. The most studied metabolic myopathies were Pompe disease (45 articles), multiple acyl-CoA dehydrogenase deficiency related to mutations in the ETFDH gene (15 articles) and systemic primary carnitine deficiency (8 articles). The most studied therapeutic management strategies for these diseases were enzyme replacement therapy, riboflavin, and carnitine supplementation, respectively.

CONCLUSIONS

This systematic review provides evidence for treatments of metabolic myopathies linked with the genetic defect in a computationally accessible format suitable for databasing in the treatabolome system, which will enable clinicians to acquire evidence on appropriate therapeutic options for their patient at the time of diagnosis.