Corrigendum to Contractility defects hinder glycoprotein VI-mediated platelet activation and affect platelet functions beyond clot contraction [Research and Practice in Thrombosis and Haemostasis Volume 8, Issue 1, January 2024, 102322]

[This corrects the article DOI: 10.1016/j.rpth.2024.102322.].

Ground-Based Mobile Measurements to Track Urban Methane Emissions from Natural Gas in 12 Cities across Eight Countries

To mitigate methane emission from urban natural gas distribution systems, it is crucial to understand local leak rates and occurrence rates. To explore urban methane emissions in cities outside the U.S., where significant emissions were found previously, mobile measurements were performed in 12 cities across eight countries. The surveyed cities range from medium size, like Groningen, NL, to large size, like Toronto, CA, and London, UK. Furthermore, this survey spanned across European regions from Barcelona, ES, to Bucharest, RO. The joint analysis of all data allows us to focus on general emission behavior for cities with different infrastructure and environmental conditions. We find that all cities have a spectrum of small, medium, and large methane sources in their domain. The emission rates found follow a heavy-tailed distribution, and the top 10% of emitters account for 60-80% of total emissions, which implies that strategic repair planning could help reduce emissions quickly. Furthermore, we compare our findings with inventory estimates for urban natural gas-related methane emissions from this sector in Europe. While cities with larger reported emissions were found to generally also have larger observed emissions, we find clear discrepancies between observation-based and inventory-based emission estimates for our 12 cities.

The CoREST repressor complex mediates phenotype switching and therapy resistance in melanoma

Virtually all patients with BRAF-mutant melanoma develop resistance to MAPK inhibitors largely through nonmutational events. Although the epigenetic landscape is shown to be altered in therapy-resistant melanomas and other cancers, a specific targetable epigenetic mechanism has not been validated. Here, we evaluated the corepressor for element 1-silencing transcription factor (CoREST) epigenetic repressor complex and the recently developed bivalent inhibitor corin within the context of melanoma phenotype plasticity and therapeutic resistance. We found that CoREST was a critical mediator of the major distinct melanoma phenotypes and that corin treatment of melanoma cells led to phenotype reprogramming. Global assessment of transcript and chromatin changes conferred by corin revealed specific effects on histone marks connected to epithelial-mesenchymal transition-associated (EMT-associated) transcription factors and the dual-specificity phosphatases (DUSPs). Remarkably, treatment of BRAF inhibitor-resistant (BRAFi-R) melanomas with corin promoted resensitization to BRAFi therapy. DUSP1 was consistently downregulated in BRAFi-R melanomas, which was reversed by corin treatment and associated with inhibition of p38 MAPK activity and resensitization to BRAFi therapies. Moreover, this activity was recapitulated by the p38 MAPK inhibitor BIRB 796. These findings identify the CoREST repressor complex as a central mediator of melanoma phenotype plasticity and resistance to targeted therapy and suggest that CoREST inhibitors may prove beneficial for patients with BRAFi-resistant melanoma.

Contractility defects hinder glycoprotein VI-mediated platelet activation and affect platelet functions beyond clot contraction

Background

Active and passive biomechanical properties of platelets contribute substantially to thrombus formation. Actomyosin contractility drives clot contraction required for stabilizing the hemostatic plug. Impaired contractility results in bleeding but is difficult to detect using platelet function tests.

Objectives

To determine how diminished myosin activity affects platelet functions, including and beyond clot contraction.

Methods

Using the myosin IIA-specific pharmacologic inhibitor blebbistatin, we modulated myosin activity in platelets from healthy donors and systematically characterized platelet responses at various levels of inhibition by interrogating distinct platelet functions at each stage of thrombus formation using a range of complementary assays.

Results

Partial myosin IIA inhibition neither affected platelet von Willebrand factor interactions under arterial shear nor platelet spreading and cytoskeletal rearrangements on fibrinogen. However, it impacted stress fiber formation and the nanoarchitecture of cell-matrix adhesions, drastically reducing and limiting traction forces. Higher blebbistatin concentrations impaired platelet adhesion under flow, altered mechanosensing at lamellipodia edges, and eliminated traction forces without affecting platelet spreading, α-granule secretion, or procoagulant platelet formation. Unexpectedly, myosin IIA inhibition reduced calcium influx, dense granule secretion, and platelet aggregation downstream of glycoprotein (GP)VI and limited the redistribution of GPVI on the cell membrane, whereas aggregation induced by adenosine diphosphate or arachidonic acid was unaffected.

Conclusion

Our findings highlight the importance of both active contractile and passive crosslinking roles of myosin IIA in the platelet cytoskeleton. They support the hypothesis that highly contractile platelets are needed for hemostasis and further suggest a supportive role for myosin IIA in GPVI signaling.

Multicentric Study on the Relation between Perceived Department Radiation Shielding Policies and Staff Radiation Shielding Conscientiousness

Personal protective equipment (PPE), including personal garments as well as in-room devices, is crucial to minimize ionizing radiation exposure during fluoroscopy-guided procedures. However, recent studies have highlighted a lack of knowledge and awareness between and within departments about the use and risks of ionizing radiation and radiation safety. Employees differ in their conscientiousness regarding PPE and perceive the program regarding PPE differently. It has been shown that being conscientious about safety precedes safety behavior and can be triggered through increased perception of the present safety policy. This study explores the relation between employees’ perception of the PPE program and their PPE conscientiousness. Employees from interventional cardiology (IC), interventional radiology (IR), and vascular surgery (VS) were invited to complete anonymously a self-administered online survey assessing the perceived PPE program, their own PPE conscientiousness, and demographics. Associations between PPE program and PPE conscientiousness were investigated using forward stepwise regression on a significance level of 5%. Study variables were standardized. Sixty-one out of the 72 (84.7%) participants answered the survey fully. The PPE program was positively associated with PPE conscientiousness [ =0.32 (CI: 0.02 to 0.51)]. This association was found to be department-dependent (p-value < 0.001). Significant mean differences in PPE conscientiousness were found between IC and IR and between IC and VS, respectively [ =1.25 (CI: 0.69 to 1.82)] and [ =0.63 (CI: 0.06 to 1.20)]. This study is the first to investigate the relation between the perceived PPE program and employees’ PPE conscientiousness. The positive association between PPE program and PPE conscientiousness suggests that employees’ perception of the prevailing PPE program in their department might influence their PPE conscientiousness. Therefore, policy makers are recommended to not only improve their PPE program but also enhance employees’ perception of the reigning PPE program in order to foster their radiation shielding behavior.

GHB: a life-threatening drug complications and outcome of GHB detoxification treatment-an observational clinical study

BACKGROUND

GHB (gammahydroxybutyrate) and its precursors are popular recreational drugs due to their sedative, anxiolytic and sexually stimulating effects. Their use has been steadily increasing in recent years. The detoxification process is complex and prone to high rates of complications while little is known about the pathophysiology. This study aims to elucidate the characteristics of GHB-addicted patients and to evaluate the risks and complications of GHB withdrawal treatment.

METHODS

This observational study describes prospectively the socioeconomic status, clinical history and course of inpatient detoxification treatment of a group of 39 patients suffering from GHB substance use disorder. Detoxification treatment took place in a highly specialized psychiatric inpatient unit for substance use disorders.

RESULTS

GHB patients were characterised by being young, well-educated and by living alone. More than 50% of the patients had no regular income. The patients were male and female in equal numbers. Detoxification treatment was complicated, with high rates of delirium (30.8%) and high need for intensive care (20.5%).

CONCLUSIONS

In our sample, GHB users were young, well-educated people and male and female in equal number. Detoxification proved to be dangerous for GHB-addicted patients. The presence of delirium and the need for transfer to an intensive care unit during detoxification treatment was extraordinarily high, even with appropriate clinical treatment. The reasons for this remain unknown. Therefore an intensive care unit should be available for GHB detoxification treatment. Further studies are needed to evaluate the options for prophylactic treatment of delirium during detoxification.

Intraoral Gavage of Second-Generation Probiotic Lactobacillus Reuteri Releasing IFN-β (LR-IFN-β) Mitigates Intestinal Irradiation Toxicity and Improves Survival During Whole Abdomen Irradiation (WAI)

PURPOSE/OBJECTIVE(S)

We sought to establish a method by which to overcome the toxicity of WAI to facilitate clinical application in Ovarian Cancer patients.

MATERIALS/METHODS

We irradiated C57BL/6J mice to 19.75 Gy WAI and assessed the primary endpoint of overall survival (OS). In a separate experiment, mice were irradiated to 12 Gy WAI and intestinal barrier integrity was compared between groups: control (0 Gy), irradiation only, 12 Gy + LR, 12 Gy + IFN-β, and 12 Gy + LR-IFN-β. Luminex assay of plasma and intestinal cells were also assayed at day 5 after WAI for radiation-induced inflammatory cytokines, and fecal matter was analyzed for LR-IFN-β clearance and levels of the LR-derived IFN-β gene from day 1 to 5 in control non-irradiated mice. Moreover, fluorescent beads were intraorally administered three hours prior to sacrifice at days 2 or 5 after WAI, and blood was assayed for beads.

RESULTS

Mice receiving LR-IFN-β (109 bacteria in 100 mL of saline) 24-hours following a single fraction of 19.75 Gy WAI showed improved OS compared to control irradiated mice (p = 0.03). LR-IFN-β gavage maintained intestinal barrier integrity (p < 0.05) by stimulating intestinal stem cells regenerations (improved levels of Lgr5+ cells, occludin, and I-CAM; p < 0.05), and reduced levels of intestinal pro-inflammatory cytokines, including IFN-γ (p = 0.0261), IL-3 (p < 0.0020) and IL-17 (p < 0.0070). There was no significant effect of control LR or intraperitoneal injection of IFN-β protein at 24 hours after WAI. Detectable levels of LR-IFN-β bacteria were also cleared from fecal matter by day three via colony assay and rt-PCR, with no detectable growth of LR-IFN-β in blood from gavaged irradiated mice (13.5 Gy WAI).

CONCLUSION

LR-IFN-β is both a feasible and effective radiation mitigator that could potentially improve the management of ovarian cancer patients. Furthermore, the subsequent addition of platinum/taxane-based chemotherapy to the combination of WAI and LR-IFN-β should reduce tumor volume while protecting the intestine and thus improve overall survival in ovarian cancer patients.

Multisite thalamic recordings to characterize seizure propagation in the human brain

Neuromodulation of the anterior nuclei of the thalamus (ANT) has shown to be efficacious in a subset of patients with refractory focal epilepsy. One important uncertainty is to what extent thalamic subregions other than the ANT could be recruited more prominently in the propagation of focal onset seizures. We designed the current study to simultaneously monitor the engagement of the ANT, mediodorsal (MD) and pulvinar (PUL) nuclei during seizures in patients who could be candidates for thalamic neuromodulation. We studied 11 patients with clinical manifestations of presumed temporal lobe epilepsy (TLE) undergoing invasive stereo-encephalography (sEEG) monitoring to confirm the source of their seizures. We extended cortical electrodes to reach the ANT, MD and PUL nuclei of the thalamus. More than one thalamic subdivision was simultaneously interrogated in nine patients. We recorded seizures with implanted electrodes across various regions of the brain and documented seizure onset zones (SOZ) in each recorded seizure. We visually identified the first thalamic subregion to be involved in seizure propagation. Additionally, in eight patients, we applied repeated single pulse electrical stimulation in each SOZ and recorded the time and prominence of evoked responses across the implanted thalamic regions. Our approach for multisite thalamic sampling was safe and caused no adverse events. Intracranial EEG recordings confirmed SOZ in medial temporal lobe, insula, orbitofrontal and temporal neocortical sites, highlighting the importance of invasive monitoring for accurate localization of SOZs. In all patients, seizures with the same propagation network and originating from the same SOZ involved the same thalamic subregion, with a stereotyped thalamic EEG signature. Qualitative visual reviews of ictal EEGs were largely consistent with the quantitative analysis of the corticothalamic evoked potentials, and both documented that thalamic nuclei other than ANT could have the earliest participation in seizure propagation. Specifically, pulvinar nuclei were involved earlier and more prominently than ANT in more than half of the patients. However, which specific thalamic subregion first demonstrated ictal activity could not be reliably predicted based on clinical semiology or lobar localization of SOZs. Our findings document the feasibility and safety of bilateral multisite sampling from the human thalamus. This may allow more personalized thalamic targets to be identified for neuromodulation. Future studies are needed to determine if a personalized thalamic neuromodulation leads to greater improvements in clinical outcome.

Universality and Nonuniversality in Distributed Nuclear Burning in Homogeneous Isotropic Turbulence

Nuclear burning plays a key role in a wide range of astrophysical stellar transients, including thermonuclear, pair instability, and core collapse supernovae, as well as kilonovae and collapsars. Turbulence is now understood to also play a key role in these astrophysical transients. Here, we demonstrate that turbulent nuclear burning may lead to large enhancements above the uniform background burning rate, since turbulent dissipation gives rise to temperature fluctuations, and in general the nuclear burning rates are highly sensitive to temperature. We derive results for the turbulent enhancement of the nuclear burning rate under the influence of strong turbulence in the distributed burning regime in homogeneous isotropic turbulence, using probability distribution function methods. We demonstrate that the turbulent enhancement obeys a universal scaling law in the limit of weak turbulence. We further demonstrate that, for a wide range of key nuclear reactions, such as C^{12}(O^{16},α)Mg^{24} and 3-α, even relatively modest temperature fluctuations, of the order of 10%, can lead to enhancements of 1-3 orders of magnitude in the turbulent nuclear burning rate. We verify the predicted turbulent enhancement directly against numerical simulations, and find very good agreement. We also present an estimation for the onset of turbulent detonation initiation, and discuss implications of our results for stellar transients.

Epigenetics and cutaneous neoplasms: from mechanism to therapy

Epigenetics encompasses heritable, reversible gene expression patterns that do not arise from mutations in genomic DNA but, rather, are regulated by DNA methylation, histone modifications, RNA modifications and ncRNAs; and epigenetic dysregulation is increasingly recognized as a mechanism of neoplastic disease progression as well as resistance to cancer therapy. This review article focuses on epigenetic modifications implicated in the progression and therapeutic resistance of common cutaneous malignancies, including basal cell carcinoma, squamous cell carcinoma, T-cell lymphoma and malignant melanoma, with an emphasis on therapeutic strategies that may be used to target such disease-associated alterations.

A phase 1 open-label trial evaluating focused ultrasound unilateral anterior thalamotomy for focal onset epilepsy

OBJECTIVE

Focused ultrasound ablation (FUSA) is an emerging treatment for neurological and psychiatric diseases. We describe the initial experience from a pilot, open-label, single-center clinical trial of unilateral anterior nucleus of the thalamus (ANT) FUSA in patients with treatment-refractory epilepsy.

METHODS

Two adult subjects with treatment-refractory, focal onset epilepsy were recruited. The subjects received ANT FUSA using the Exablate Neuro (Insightec) system. We determined the safety and feasibility (primary outcomes), and changes in seizure frequency (secondary outcome) at 3, 6, and 12 months. Safety was assessed by the absence of side effects, that is, new onset neurological deficits or performance deterioration on neuropsychological testing. Feasibility was defined as the ability to create a lesion within the anterior nucleus. The monthly seizure frequency was compared between baseline and postthalamotomy.

RESULTS

The patients tolerated the procedure well, without neurological deficits or serious adverse events. One patient experienced a decline in verbal fluency, attention/working memory, and immediate verbal memory. Seizure frequency reduced significantly in both patients; one patient was seizure-free at 12 months, and in the second patient, the frequency reduced from 90-100 seizures per month to 3-6 seizures per month.

SIGNIFICANCE

This is the first known clinical trial to assess the safety, feasibility, and preliminary efficacy of ANT FUSA in adult patients with treatment-refractory focal onset epilepsy.

The community capacity curve applied to reforestation: a framework to support success

Community involvement is critical for the success of many interventions designed to promote reforestation. To secure this involvement, it helps to recognize that communities are heterogenous both within and among themselves and possess diverse mixes of livelihood assets required to implement reforestation. We explore the relationship between livelihood assets and reforestation success and outline a conceptual model that we call the community capacity curve (CCC) applied to reforestation. We argue that the shape of the CCC is sigmoidal. Importantly, communities at the lower end of the CCC have limited capacity to implement reforestation projects without substantial and ongoing capacity building and other sorts of support, including through livelihood projects that improve food security and provide cash benefits. Communities at the higher part of the CCC have greater capacity to implement reforestation projects, especially projects focused on biodiversity and environmental services. The CCC can help design, implement, monitor and assess reforestation projects, select appropriate livelihood activities and types of reforestation, select communities suited to a reforestation project, guide implementation and understand projects' successes and failure. The CCC also provides a framework to engage with policy makers and funding bodies to explore the types of support for communities to reforest successfully. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

Open Retroperitoneal Repair for Complex Abdominal Aortic Aneurysms

Background  Open surgical repair (OSR) of complex abdominal aortic aneurysms (CAAAs) can be challenging. We frequently utilize the retroperitoneal (RP) approach for such cases. We audited our outcomes with the aim of establishing the utility and safety of this approach.

Methods  Retrospective analysis was performed of all patients undergoing OSR of an unruptured CAAA via a RP approach in our center over a 7-year period. Data on repairs via a transperitoneal (TP) approach were collected to provide context. Demographic, operative, radiological, and biochemical data were collected. The primary outcome measure was 30-day/inpatient mortality. Secondary outcomes included the need for reoperation, incidence of postoperative chest infection, acute kidney injury (AKI) and length of stay (LOS). All patients received aortic clamping above at least one main renal artery.

Results  One hundred and three patients underwent OSR of an unruptured CAAA; 55 via a RP approach, 48 TP. The RP group demonstrated a more advanced pattern of disease with a larger median maximum diameter (65 vs. 61 mm, p = 0.013) and a more proximal extent. Consequently, the rate of supravisceral clamping was higher in RP repair (66 vs. 15%, p  < 0.001). Despite this there were no differences in the observed early mortality (9.1 vs. 10%, NS); incidence of reoperation (10.9 vs. 12.5%, NS), chest infection (32.7 vs. 25%, NS), and AKI (52.7 vs. 45.8%, NS); or median LOS (10 vs. 12 days, NS) following RP and TP repair.

Conclusion  OSR of CAAAs carries significant 30-day mortality. In patients unsuitable for fenestrated endovascular aortic repair or those desiring a durable long-term solution, OSR can be performed through the RP or TP approach. This study has demonstrated that in our unit RP repair facilitates treatment of more advanced AAA utilizing complex proximal clamp zones with similar perioperative morbidity and mortality compared with TP cases utilizing more distal clamping.

Pulsed-Focused Ultrasound Provides Long-Term Suppression of Epileptiform Bursts in the Kainic Acid-Induced Epilepsy Rat Model

Focused ultrasound (FUS) has potential utility for modulating regional brain excitability and possibly aiding seizure control; however, the duration of any beneficial effect is unknown. This study explores the efficacy and time course of a short series of pulsed FUS in suppressing EEG epileptiform spikes/bursts in a kainic acid (KA) animal model of temporal lobe epilepsy. Forty-four male Sprague-Dawley rats were recorded for 14 weeks with EEG while software calculated EEG numbers of epileptiform spikes and bursts (≥ 3 spikes/s). Four regimens of FUS given in a single session at week 7 were evaluated, with mechanical index (MI) ranging from 0.25 to 0.75, intensity spatial peak temporal average (ISPTA) from 0.1 to 2.8 W per cm2, duty cycle from 1 to 30%, and three consecutive pulse trains for 5 or 10 min each. Controls included sham injections in four and KA without FUS in eleven animals. Histological analysis investigated tissue effects. All animals receiving KA evidenced EEG spikes, averaging 10,378 ± 1651 spikes per 8 h and 1255 ± 199 bursts per 8 h by weeks 6-7. The KA-only group showed a 30% of increase in spikes and bursts by week 14. Compared to the KA-only group, spike counts were reduced by about 25%, burst counts by about 33%, and burst durations by about 50% with FUS. Behavioral seizures were not analyzed, but electrographic seizures longer than 10 s declined up to 70% after some FUS regimens. Repeated-measure ANOVA showed a significant effect of higher intensity and longer sonication duration FUS treatment using 0.75-MI, ISPTA 2.8 W/cm2, 30% duty cycle for 10-min sonications (group effect, F (4, 15) = 6.321, p < 0.01; interaction effect, F (44, 165) = 1.726, p < 0.01), with the hippocampal protective effect lasting to week 14, accompanied by decreased inflammation and gliosis effect. In contrast, spike and burst suppression were achieved using an FUS regimen with 0.25-MI ISPTA 0.5 W/cm2, 30% duty cycle for 10-min sonications. This regimen reduced inflammation and gliosis at weeks 8-14 and protected hippocampal tissue. This study demonstrates that low-intensity pulsed ultrasound can modulate epileptiform activity for up to 7 weeks and, if replicated in the clinical setting, might be a practical treatment for epilepsy.

European Expert Opinion on Infrarenal Sealing Zone Definition and Management in Endovascular Aortic Repair Patients: A Delphi Consensus

PURPOSE

The purpose of the study was to provide a consensus definition of the infrarenal sealing zone and develop an algorithm to determine when and if adjunctive procedure(s) or reintervention should be considered in managing patients undergoing endovascular aortic repair (EVAR) for infrarenal abdominal aortic aneurysm (AAA).

METHODS

A European Advisory Board (AB), made up of 11 vascular surgeons with expertise in EVAR for AAA, was assembled to share their opinion regarding the definition of preoperative and postoperative infrarenal sealing zone. Information on their current clinical practice and level of agreement on proposed reintervention paths was used to develop an algorithm. The process included 2 virtual meetings and 2 rounds of online surveys completed by the AB (Delphi method). Consensus was defined as reached when ≥ 8 of 11 (73%) respondents agreed or were neutral.

RESULTS

The AB reached complete consensus on definitions and measurement of the pre-EVAR target anticipated sealing zone (TASZ) and the post-EVAR real achieved sealing zone (RASZ), namely, the shortest length between the proximal and distal reference points as defined by the AB, in case of patients with challenging anatomies. Also, agreement was achieved on a list of 4 anatomic parameters and 3 prosthesis-/procedure-related parameters, considered to have the most significant impact on preoperative and postoperative sealing zones. Furthermore, the agreement was reached that in the presence of visible neck-related complications, both adjunctive procedure(s) and reintervention should be contemplated (100% consensus). In addition, adjunctive procedure(s) or reintervention can be considered in the following cases (% consensus): insufficient sealing zone on completion imaging (91%) or on the first postoperative computed tomography (CT) scan (91%), suboptimal sealing zone on completion imaging (73%) or postoperative CT scan (82%), and negative evolution of the actual sealing zone over time (91%), even in the absence of visible complications.

CONCLUSIONS

AB members agreed on definitions of the pre- and post-EVAR infrarenal sealing zone, as well as factors of influence. Furthermore, a clinical decision algorithm was proposed to determine the timing and necessity of adjunctive procedure(s) and reinterventions.

Micromechanical and Ultrastructural Properties of Abdominal Aortic Aneurysms

Abdominal aortic aneurysms are a common condition of uncertain pathogenesis that can rupture if left untreated. Current recommended thresholds for planned repair are empirical and based entirely on diameter. It has been observed that some aneurysms rupture before reaching the threshold for repair whilst other larger aneurysms do not rupture. It is likely that geometry is not the only factor influencing rupture risk. Biomechanical indices aiming to improve and personalise rupture risk prediction require, amongst other things, knowledge of the material properties of the tissue and realistic constitutive models. These depend on the composition and organisation of the vessel wall which has been shown to undergo drastic changes with aneurysmal degeneration, with loss of elastin, smooth muscle cells, and an accumulation of isotropically arranged collagen. Most aneurysms are lined with intraluminal thrombus, which has an uncertain effect on the underlying vessel wall, with some authors demonstrating a reduction in wall stress and others a reduction in wall strength. The majority of studies investigating biomechanical properties of ex vivo abdominal aortic aneurysm tissues have used low-resolution techniques, such as tensile testing, able to measure the global material properties at the macroscale. High-resolution engineering techniques such as nanoindentation and atomic force microscopy have been modified for use in soft biological tissues and applied to vascular tissues with promising results. These techniques have the potential to advance the understanding and improve the management of abdominal aortic aneurysmal disease.

Critical COVID-19 rarely associated with left ventricular systolic impairment

Introduction

For some individuals infection with SARS-CoV-2 leading to COVID-19 can result in a life-threatening multi-system disease. Multiple potential pathophysiological mechanisms for the development of cardiovascular complications have been postulated [1]. Early reports suggested that more than a third of hospitalised patients undergoing TTE had evidence of LV impairment [2].

Purpose

To ascertain the incidence of ventricular impairment among critically ill adults with COVID-19 admitted to the intensive care unit (ICU).

Methods

Retrospective analysis of transthoracic echocardiograms (TTE) performed on patients admitted to ICU with COVID-19 between 10th March and 10th May 2020. Archived studies were reviewed by accredited professionals. Studies were performed according to a modified British Society of Echocardiography (BSE) Level 1 protocol [3], with the addition of right ventricle (RV) focused apical 4 chamber, as well as apical 2 and 3 chamber views, and without ECG synchronisation as per infection control protocols. In the majority of patients the left ventricular ejection fraction (LVEF) was estimated from biplane Simpson's method. The RV function was assessed using the TAPSE in most patients. In the remaining patients the LV or RV function was visually assessed.

Results

Of 179 patients admitted to ICU, 85 (47.5%) had at least one TTE of diagnostic quality. Studies were performed a median of 7 days after ICU admission (IQR 3–17 days). Baseline and clinical characteristics and key echocardiographic measurements are summarised in table 1. The majority of patients were undergoing mechanical ventilation at the time of the scan (94.1%). One hundred and fifty-nine patients (89%) had elevated Troponin T (≥14ng/L) on the day of the study. LV systolic impairment (LVSD) was present in 5 patients (6.0%). This was known to be chronic in 3 patients (1 with coronary artery disease, 1 with chemotherapy induced cardiomyopathy and 1 with dilated cardiomyopathy of unknown aetiology), whilst pre-morbid cardiac function was unknown in the other 2 patients. No patient had severe LVSD (LVEF ≤35%). RV systolic dysfunction (RVSD) was found in 25 patients (31.3%). Amongst patients receiving mechanical ventilation there was no significant difference in Positive End Expiratory Pressure (PEEP) between patients with and without RVSD (9.4cmH2O vs. 9.8cmH2O, p=0.64), however there was a non-significant trend towards lower PaO2/FiO2 (P/F ratio) amongst patients with RVSD (18.9kPa vs 25.7kPa, p=0.07).

Conclusions

In contrast to other studies which have reported high frequency of LV impairment amongst hospitalised patients with COVID-19 [3], de novo LVSD was rarely found in this study, occurring in just 2 patients (2.4%), and being severe in neither. RV dilatation and systolic impairment were commonly found. A trend towards lower P/F ratios in patients with RVSD suggests severity of lung injury may be a factor in developing RV impairment.

Funding Acknowledgement

Type of funding sources: None.

1133 Long Term Survival After Standard EVAR: Have We Started to Treat The EVAR-2 Patient?

Aim

Abdominal aortic aneurysm repair was traditionally preformed with open surgical repair (OSR). Recently endovascular aneurysm repair (EVAR) has increased in popularity due to its less invasive nature particularly in those deemed unfit for OSR. The EVAR-2 trial found no significant difference between BMT and EVAR in the 30 days all-cause mortality. This questioned whether EVAR was the best option in those medically unfit for OSR.

Method

Elective EVAR procedures from the 1st April 2012 to 1st September 2017 were analysed with Kaplan-Meier graphs. The patient data was stratified by year, age group and EVAR risk scoring.

Results

The all-cause mortality at 30 days was 1.8%, at 6 months it was 7%, and at 4 years it was 19.8%. There was no significant difference with log rank analysis of the year of EVAR operation and consultant (P &gt; 0.05). The log rank analysis found a significant difference between the stratified age groups (P &lt; 0.001) and the EVAR scoring (P = 0.032). At all time-points the RLUH EVAR patients had a lower all-cause mortality compared to the EVAR-2. At the 4-year time point, the RLUH EVAR group had lower all- cause mortality than both EVAR-1 and EVAR-2 trials.

Conclusions

The retrospective audit data from 2012-2017, suggest the RLUH EVAR treatment practice is not falling into the EVAR-2 trial findings. At all time-points the RLUH EVAR patients had a lower all-cause mortality compared to the EVAR-2. Therefore, it can be concluded the RLUH is not treating EVAR-2 patients.

Onyx™ Cast Fragmentation After Embolization of Endoleaks

PURPOSE

Endoleaks are common following endovascular aneurysm repair (EVAR), and the liquid embolic material Onyx has been widely used in their treatment. We report our experience of long-term morphological changes of Onyx casts on surveillance imaging.

MATERIALS AND METHODS

We identified 10 patients over 10 years who underwent Onyx embolization in our institution. Morphological changes of Onyx casts were assessed on surveillance radiographs and computed tomography (CT) scans. Relevant outcome data and sequelae were obtained via electronic patient records.

RESULTS

Twelve procedures were performed on 10 cases, 9 for type 2, and 1 for a type 1a endoleak. Five cases showed evidence of Onyx fragmentation on follow-up imaging ranging from a single fracture to gross fragmentation with migration of fragments. Of these 5, 3 had achieved primary success but 2 went on to develop recurrence of endoleak. Onyx volume ranged from 4 to 46.5 ml (median 10.5 ml) per patient with larger volumes demonstrating the most marked fragmentation on follow-up. Follow-up ranged from 9 months to 8 years (median 2.25 years).

CONCLUSION

To our knowledge, this is the first report of Onyx fragmentation after endoleak embolization. If long-term morphological stability of the Onyx cast is necessary to maintain aneurysm seal, then Onyx may not offer a permanent solution to some patients with post-EVAR endoleaks. Our study cannot ascertain whether the observed changes were the cause or the effect of ongoing aneurysm growth, persistent endoleak, and/or other forces acting on the solidified polymer, but it raises important questions on the use of Onyx in this setting.

843 Improving Practical Skills Training with In-Situ Trauma Simulation

Introduction

Safe and effective management of trauma patients requires numerous practical skills. Our in-situ trauma simulation identified key areas requiring increased training and exposure. This enabled improvement to education, patient safety and efficiency when managing these emergencies.

Method

We carried out a simulated trauma call according to ATLS principles, recording the time and person completing each task. Key areas for improvement were identified; most notably the application of Femoral Traction Splints (FTS). 0/7 doctors present were not able to do this. Subsequently, a formal training day was delivered, with 38 attendees across specialties, assessing confidence before and after the session.

Results

Prior to the training session, 52.6% of attendees did not have formal teaching using FTS and 65.8% had never used one. Confidence with FTS application was measured on a scale of 1 (not confident) to 5 (very confident), with an average score of 2.6/5.

After training, the average confidence score was 4.7/5 (p &lt; 0.01). 100% of participants found the session very useful.

Conclusions

In-situ simulation allows identification of key areas for improvement in training of practical skills. Essential tailored teaching can then be delivered to increase exposure and confidence for these necessary practical skills.

755 Elective Surgery in the COVID-19 Pandemic: Outcomes of 100 Consecutive Cases

Introduction

The COVID-19 pandemic halted elective surgical activity. Basildon University Hospital established an elective Green Zone for COVID-19 swab negative patients who isolated for 14 days. This study reviewed the outcomes of the first 100 patients.

Method

A single-centre study was performed. Demographic and perioperative electronic data were supplemented with telephone follow-up for the first 100 Green Zone patients and analysed in Microsoft Excel.

Results

One hundred Green Zone patients underwent surgery between 21/05/2020 and 16/06/2020. The median age was 55 (14-88) years. 52% were female. Their operations were performed by General Surgery (39%), Gynaecology (17%), Vascular Surgery (14%), Oral Surgery (12%), ENT (9%), Urology (8%), and Pain Management (1%).

Preoperatively, 100% had a negative SARS-CoV-2 swab and one had CT evidence of mild resolving COVID-19. Two patients had postoperative SARS-CoV-2 swabs, both negative. Median length of stay was 0 (0-7) days. 84% responded to telephone follow-up at a median 25 (13-54) postoperative days, 69% of whom were asymptomatic There were no 30-day major complications (>Clavien-Dindo IIIa) or 90-day mortality.

Conclusions

Elective surgery can be safe during the COVID-19 pandemic, with appropriate measures in place. This has significant implications in the context of an ever-expanding NHS waiting list during a pandemic of uncertain duration.

Recent Developments in Species Sensitivity Distribution Modeling

The species sensitivity distribution (SSD) is a statistical approach that is used to estimate either the concentration of a chemical that is hazardous to no more than x% of all species (the HCx) or the proportion of species potentially affected by a given concentration of a chemical. Despite a significant body of published research and critical reviews over the past 20 yr aimed at improving the methodology, the fundamentals remain unchanged. Although there have been some recent suggestions for improvements to SSD methods in the literature, in general, few of these suggestions have been formally adopted. Furthermore, critics of the approach can rightly point to the fact that differences in technical implementation can lead to marked differences in results, thereby undermining confidence in SSD approaches. Despite the limitations, SSDs remain a practical tool and, until a demonstrably better inferential framework is available, developments and enhancements to conventional SSD practice will and should continue. We therefore believe the time has come for the scientific community to decide how it wants SSD methods to evolve. The present study summarizes the current status of, and elaborates on several recent developments for, SSD methods, specifically, model averaging, multimodality, and software development. We also consider future directions with respect to the use of SSDs, with the ultimate aim of helping to facilitate greater international collaboration and, potentially, greater harmonization of SSD methods. Environ Toxicol Chem 2021;40:293-308. © 2020 SETAC.

Epileptogenic network of focal epilepsies mapped with cortico-cortical evoked potentials

OBJECTIVE

The goal of this study was to investigate the spatial extent and functional organization of the epileptogenic network through cortico-cortical evoked potentials (CCEPs) in patients being evaluated with intracranial stereoelectroencephalography.

METHODS

We retrospectively included 25 patients. We divided the recorded sites into three regions: epileptogenic zone (EZ); propagation zone (PZ); and noninvolved zone (NIZ). The root mean square of the amplitudes was calculated to reconstruct effective connectivity network. We also analyzed the N1/N2 amplitudes to explore the responsiveness influenced by epileptogenicity. Prognostic analysis was performed by comparing intra-region and inter-region connectivity between seizure-free and non-seizure-free groups.

RESULTS

Our results confirmed that stimulation of the EZ caused the strongest responses on other sites within and outside the EZ. Moreover, we found a hierarchical connectivity pattern showing the highest connectivity strength within EZ, and decreasing connectivity gradient from EZ, PZ to NIZ. Prognostic analysis indicated a stronger intra-EZ connection in the seizure-free group.

CONCLUSION

The EZ showed highest excitability and dominantly influenced other regions. Quantitative CCEPs can be useful in mapping epileptic networks and predicting surgical outcome.

SIGNIFICANCE

The generated computational connectivity model may enhance our understanding of epileptogenic networks and provide useful information for surgical planning and prognosis prediction.

Randomized, Placebo Controlled Trial of NPT088, A Phage-Derived, Amyloid-Targeted Treatment for Alzheimer's Disease

The engineered fusion protein NPT088 targets amyloid in vitro and in animal models of Alzheimer's disease. Previous studies showed that NPT088 treatment reduced β-amyloid plaque and tau aggregate loads in mouse disease models. Here, we present the results from an initial clinical study of NPT088 in patients with mild to moderate Alzheimer's disease. Patients were treated with 4 dose levels of NPT088 for 6 months to evaluate its safety and tolerability. Exploratory measurements included measurement of change in β-amyloid plaque and tau burden utilizing Positron Emission Tomography imaging as well as measures of Alzheimer's disease symptoms. At endpoint NPT088 was generally safe and well-tolerated with the most prominent finding being infusion reactions in a minority of patients. No effect of NPT088 on brain plaques, tau aggregates or Alzheimer's disease symptoms was observed.

Anti-seizure therapy with a long-term, implanted intra-cerebroventricular delivery system for drug-resistant epilepsy: A first-in-man study

BACKGROUND

A clinical feasibility study was undertaken at a single center of long-term intra-cerebroventricular drug delivery of the anti-seizure medication valproic acid, into the cerebrospinal fluid (CSF) in order to treat drug resistant focal seizures, using an implantable infusion system. The primary objective was to establish the dose range of VPA administered in this manner. Secondarily, safety, pharmacokinetics (PK) and a preliminary estimate of effectiveness were evaluated.

METHODS

In this single arm study, five adult subjects, with 29-234 focal onset seizures per month from a seizure focus involving the mesial temporal lobe were implanted with the system (clinicaltrials.gov identifier NCT02899611). Oral valproic acid (VPA) had previously been ineffective in all subjects. Post-surgery, pharmacokinetic studies of CSF infused VPA were performed. Valproic acid doses were increased stepwise in a standardised protocol.

FINDINGS

The procedure and implantation were well-tolerated by all subjects. Four subjects responded with > 50% seizure reduction at the highest tested dose of 160 mg/day. Two subjects experienced extended periods of complete seizure freedom. All five subjects reported significant quality of life improvement. No clinical dose limiting side effects were encountered and there was no evidence of local periventricular toxicity in three subjects who were evaluated with imaging (T2 MRI). Side effects included nausea and appetite loss but were not dose-limiting. Mean CSF valproic acid levels were 45 μg per ml (range 20-120 μg per ml), with corresponding serum levels of 4-14 μg per ml.  Subjects have received therapy for up to 2.5 years in total . The efficacy analysis presented focuses on the period of time with the current pump with a mean 12.5 months, range 11.5-15 months. Pump failure requiring reimplantation was a significant initial issue in all subjects but resolved with use of pumps suitably compatible with long-term exposure to valproic acid.

INTERPRETATION

The study demonstrated that chronic intraventricular administration of valproic acid is safe and effective in subjects with medically refractory epilepsy over many months. The procedure for implanting the infusion system is safe and well-tolerated. High CSF levels are achieved with corresponding low serum levels and this therapy is shown to be effective despite unsuccessful earlier use of oral valproate preparations. Drug side effects were minimal.

FUNDING

The study was funded by Cerebral Therapeutics Inc., Suite 137 12635 East Montview Blvd Aurora CO 80045.

Virtual arthroplasty follow-up: five-year data from a district general hospital

INTRODUCTION

Follow-up after hip and knee arthroplasty is advocated to identify asymptomatic loosening and improve patient satisfaction. There are, however, financial and time implications associated with regular clinic appointments. Assessment through virtual means has been suggested as an alternative.

MATERIALS AND METHODS

At the West Suffolk Hospital, following arthroplasty surgery of the lower limb, patients are followed-up via a questionnaire at one and five years postoperatively, then subsequently at five-yearly intervals. Patients are recalled based on the outcome of these assessments. Using a locally compiled data base we identified all patients reviewed between 2011 and 2015 using this virtual assessment process and examined their outcomes.

RESULTS

During the five years of follow-up, 5,380 patients were eligible for assessment. Compliance varied from 77% follow up for hips and 83% for knees. Ten patients were recalled following total hip replacement, eight for x-ray changes and one for a poor satisfaction score. Five went on to undergo revision surgery. Some 56 recalls to clinic following knee arthroplasty were seen; 42 due to a poor Oxford Knee Score, 6 with associated x-ray abnormalities and 6 isolated abnormal x-rays. Five subsequently underwent revision surgery; 30 (54%) were discharged after initial review and 18 (32%) were referred to different subspecialties.As a result of the virtual review process, 4,219 clinic appointments were avoided, with no documented admissions as a result of a missed complication from virtual review.

DISCUSSION

A virtual arthroplasty clinic significantly reduces the number of patients attending regular follow-up clinics, without compromising safe practice.

Nitrogen removal from coke making wastewater through a pre-denitrification activated sludge process

Under the Industrial Emissions Directive (IED), coke production wastewater must be treated to produce an effluent characterised by a total nitrogen (TN) <50 mg/L. An anoxic-aerobic activated sludge pilot-plant (1 m³) fed with coke production wastewater was used to investigate the optimal operational requirements to achieve such an effluent. The loading rates applied to the pilot-plant varied between 0.198-0.418 kg COD/m³.day and 0.029-0.081 kg TN/m³.day, respectively. The ammonia (NH₄⁺-N) removals were maintained at 96%, after alkalinity addition. Under all conditions, phenol and SCN^- remained stable at 96% and 100%, respectively with both being utilised as carbon sources during denitrification. The obtained results showed that influent soluble chemical oxygen demand (sCOD) to TN ratio of should be maintained at >5.7 to produce an effluent TN <50 mg/L. Furthermore, nitrite accumulation was observed under all conditions indicating a disturbance to the denitrification pathway. Overall, the anoxic-aerobic activated sludge process was shown to be a robust and reliable technology to treat coke making wastewater and achieve the IED requirements. Nevertheless, the influent to the anoxic tank should be monitored to ensure a sCOD:TN ratio >5.7 or, alternately, the addition of an external carbon source should be considered.

Synthetic Polyampholytes as Macromolecular Cryoprotective Agents

A series of polyampholytes based on different molar ratios on N, N-dimethylaminopropyl methacrylamide (DMAPMA), acrylic acid (AA), and optionally, N- tert-butylacrylamide ( t-BuAAm), were prepared by free radical copolymerization, and tested as DMSO-free cryoprotective agents for 3T3 fibroblast cells by using a standard freeze-rethaw protocol. Polybetaines prepared by reaction of DMAPMA homo and copolymers with 1,3-propane sultone were used as additional controls. Results showed strong effects of copolymer composition, molecular weight, polymer and NaCl concentrations, on post-thaw cell viability. Binary (DMAPMA/AA) copolymers showed best post-thaw cell viability of 70% at a 30/70 mol % ratio of DMAPMA/AA, which increased to 90% upon introduction of 9 mol % t-BuAAm while maintaining the 30/70 mol % cation/anion ratio. The use of acrylamide linkages in DMAPMA ensures absence of hydrolytic loss of cationic side chains. These polyampholytes were found to decrease ice crystal size and to form a polymer-rich, ice-free layer around cells, reducing damage from intercellular ice crystals during both freezing and thawing steps. These polyampholytes also dehydrate cells during freezing, which helps protect cells from intracellular ice damage. While cell viability immediately after thawing was high, subsequent culturing revealed poor attachment and long-term viability, which is attributed to residual cell damage from intracellular ice formation. Addition of 2 wt % DMSO or 1% BSA to the polymer-based freeze medium was found to mitigate this damage and result in post-thaw viabilities matching those achieved with 10 wt % DMSO.