Handling 'carbon footprint' in orthopaedics

INTRODUCTION

The National Health Service contributes 4%-5% of England and Wales' greenhouse gases and a quarter of all public sector waste. Between 20% and 33% of healthcare waste originates from a hospital's operating room, and up to 90% of waste is sent for costly and unneeded hazardous waste processing. The goal of this study was to quantify the amount and type of waste produced during a selection of common trauma and elective orthopaedic operations, and to calculate the carbon footprint of processing the waste.

METHODS

Waste generated for both elective and trauma procedures was separated primarily into clean and contaminated, paper or plastic, and then weighed. The annual carbon footprint for each operation at each site was subsequently calculated.

RESULTS

Elective procedures can generate up to 16.5kg of plastic waste per procedure. Practices such as double-draping the patient contribute to increasing the quantity of waste. Over the procedures analysed, the mean total plastic waste at the hospital sites varied from 6 to 12kg. One hospital site undertook a pilot of switching disposable gowns for reusable ones with a subsequent reduction of 66% in the carbon footprint and a cost saving of £13,483.89.

CONCLUSIONS

This study sheds new light on the environmental impact of waste produced during trauma and elective orthopaedic procedures. Mitigating the environmental impact of the operating room requires a collective drive for a culture change to sustainability and social responsibility. Each clinician can have an impact upon the carbon footprint of their operating theatre.

The carbon footprint of arthroscopic procedures

INTRODUCTION

The healthcare sector contributes the equivalent of 4.4% of global net emissions to the climate carbon footprint; between 20% and 70% of healthcare waste originates from a hospital's operating theatre and up to 90% of waste is sent for costly and unneeded hazardous waste processing. This study aimed to quantify the amount and type of waste produced during an arthroscopic anterior cruciate ligament reconstruction (ACLR) and an arthroscopic rotator cuff repair (RCR), calculate the carbon footprint and assess the cost of the waste disposal.

METHODS

The amount of waste generated from ACLR and RCR procedures was calculated across a range of hospital sites. The waste was separated primarily into clean and contaminated, paper or plastic. Both carbon footprint and cost of disposal across the hospital sites was subsequently calculated.

RESULTS

RCR generated 3.3-15.5kg of plastic waste and 0.9-2.3kg of paper waste. ACLR generated 2.4-9.6kg of plastic waste and 1.1-1.6kg of paper waste. The cost to process waste varies widely between hospital sites, waste disposal contractors and method of waste disposal. The annual burden of the included hospital sites for the arthroscopic procedures undertaken was 6.2 tonnes of carbon dioxide.

CONCLUSIONS

The data collected demonstrated a significant variability in waste production and cost for waste disposal between hospital sites. At a national level, consideration should be given to the procurement of appropriate products such that waste can be efficiently recycled or disposed of by environmentally sustainable methods.

Post-Prostatectomy Risk Stratification of Biochemical Recurrence Using Transfer Learning-Based Multi-Modal Artificial Intelligence

PURPOSE/OBJECTIVE(S)

For patients undergoing radical prostatectomy for prostate cancer (PCa), accurate risk stratification is essential to guide post-prostatectomy therapeutic decision making. Recently, there has been success in the use of multi-modal artificial intelligence models for men after prostate biopsy to aid in risk stratification. Herein, we trained and tested a TRansfer learning-based multi-modal Artificial InteLligence model (TRAIL) for biochemical recurrence (BCR) risk stratification following radical prostatectomy.

MATERIALS/METHODS

Patients contained within a prospective PCa registry at a single institution were utilized. Digital pathology slides from the diagnostic biopsies prior to radical prostatectomy for patients with clinically localized PCa were scanned at 20x resolution. Features were extracted for the TRAIL model from pathology slides via two transfer learning steps: (1) InceptionResNetv2 that first determines a heatmap of tumor areas, and (2) A ResNet18 that extracts representative features from the high tumor probability areas. Least Absolute Shrinkage and Selection Operator (LASSO) was used for feature selection from the pathology-extracted features. Finally, TRAIL combines the clinical and pathology-extracted features via a classification ensemble model based on weak tree learners to predict 2- and 5-year BCR defined as two consecutive serum PSA levels ≥0.2 ng/mL. TRAIL training was performed on 250 patients and was then locked and applied to the test set of 125 patients. Accuracy and the area under the curve (AUC) were calculated. Comparison to CAPRA-S and to clinical-only features were assessed.

RESULTS

A total of 818 digital whole pathology biopsy slides from 375 patients treated with subsequent radical prostatectomy were included. Surgical margins were positive in 29% of the patients, and 41% had extra-prostatic extension. The median follow-up was 48 months (Range: 1-132 months). The rates of 2-and 5-year BCR were 11% and 18% respectively. A total of 19 digital pathology-driven features were included in TRAIL. Clinical factors included age, ISUPG, Gleason score, PSA, pathological T and N stages, surgical margin involvement, and the presence of extra-prostatic extension. On the testing set, TRAIL achieved a 2-year BCR AUC of 0.76 and accuracy of 0.87, and was superior to CAPRA-S (AUC = 0.57) and clinical-only features (AUC 0.50, accuracy 0.14). For 5-year BCR, TRAIL achieved an AUC of 0.69 and accuracy of 0.78, and performed better than CAPRA-S (AUC = 0.58), and clinical only features (AUC = 0.50, accuracy = 0.23).

CONCLUSION

Through a combination of deep and ensemble learning, TRAIL incorporates clinical and histopathology features, enabling an improved BCR risk stratification post-prostatectomy when compared to the currently used clinicopathologic models. Future work with larger datasets with metastatic events is warranted to further optimize the model for clinical use.

Evidence of Electron Heating by Alpha Particles in JET Deuterium-Tritium Plasmas

The fusion-born alpha particle heating in magnetically confined fusion machines is a high priority subject for studies. The self-heating of thermonuclear fusion plasma by alpha particles was observed in recent deuterium-tritium (D-T) experiments on the joint European torus. This observation was possible by conducting so-called "afterglow" experiments where transient high fusion yield was achieved with neutral beam injection as the only external heating source, and then termination of the heating at peak performance. This allowed the first direct evidence for electron heating of plasmas by fusion-born alphas to be obtained. Interpretive transport modeling of the relevant D-T and reference deuterium discharges is consistent with the alpha particle heating observation.

The effect of tibialis anterior weakness on foot drop and toe clearance in patients with facioscapulohumeral dystrophy

BACKGROUND

Facioscapulohumeral dystrophy is a genetic disease characterized by progressive muscle weakness leading to a complex combination of postural instability, foot drop during swing and compensatory strategies during gait that have been related to an increased risk of falling. The aim is to assess the effect of tibialis anterior muscle weakness on foot drop and minimum toe clearance of patients with facioscapulohumeral dystrophy during gait.

METHODS

Eight patients allocated to a subgroup depending on the severity of tibialis anterior muscle weakness, assessed by manual muscle testing (i.e., severe and mild weakness), and eight matched control participants underwent gait analysis at self-selected walking speeds.

FINDINGS

Walking speed, for all facioscapulohumeral dystrophy patients, and step length, for patients with severe weakness only, were significantly decreased compared to control participants. Minimum toe clearance was similar across all groups, but its variability was increased only for patients with severe weakness. A greater foot drop was systematically observed for patients with severe weakness during swing and only in late swing for patients with mild weakness. Individual strategies to compensate for foot drop remain unclear and may depend on other muscle impairment variability.

INTERPRETATION

Although all patients were able to control the average height of their foot trajectory during swing, patients with severe tibialis anterior muscle weakness exhibited increased foot drop and minimum toe clearance variability. Manual muscle testing is a simple, cheap and effective method to assess tibialis anterior muscle weakness and seems promising to identify facioscapulohumeral dystrophy patients with an increased risk of tripping.

A model of non-Maxwellian electron distribution function for the analysis of ECE data in JET discharges

Recent experiments performed in JET at high level of plasma heating, in preparation of, and during the DT campaign have shown significant discrepancies between electron temperature measurements by Thomson Scattering (TS) and Electron Cyclotron Emission (ECE). In order to perform a systematic analysis of this phenomenon, a simple model of bipolar distortion of the electron distribution function has been developed, allowing analytic calculation of the EC emission and absorption coefficients. Extensive comparisons of the modelled ECE spectra (at both the 2nd and the 3rd harmonic extraordinary mode) with experimental measurements display good agreement when bulk electron distribution distortions around 1-2 times the electron thermal velocity are used and prove useful for a first level of analysis of this effect.

The Effect of Pollen Diet Composition and Quantity on Diapause Survival and Performance in an Annual Pollinator (Bombus Impatiens)

Most pollination services are provided by annual bees that go through a winter diapause, during which they are exposed to extreme temperatures, pathogens, and starvation. The ability of bees to successfully face these stressors during diapause and subsequently initiate a nest depends on their overall nutritional state and an adequate preparatory diet. Here, we used queens of the common eastern bumble bee, Bombus impatiens, to examine how pollen diets varying in their protein to lipid ratio and total nutrient amounts affected queen performance during and after diapause. We compared diapause survival and reproductive performance post-diapause across different diets and found that queen survival was highest when pollen had a nutritional ratio of approximately 5:1 (protein to lipid). This diet is significantly enriched in proteins compared to the pollen fed to bumble bees in the lab (1:1) or commonly available in agricultural landscapes. Altering the quantity of macronutrients within this ratio did not improve survival or performance. Our results emphasize the importance of adequate nutrition for diapause performance in bees with annual life cycles and the importance of providing annual bees with floral provisioning based on their individual nutritional targets.

Investigation of Te measurements discrepancies between ECE and Thomson diagnostics in high-performance plasmas in JET

For high-temperature JET and TFTR discharges, electron cyclotron emission (ECE) measurements of central electron temperature were systematically found to be up to 20% higher than those taken with Thomson scattering. In recent high-performance JET discharges, central Te measurements, performed with LIDAR Thomson scattering and the X-mode ECE interferometer, have been studied in a large database, including deuterium (DD), and deuterium-tritium plasmas (DT). Discrepancies between Te measurements have been observed outside of the experimental uncertainties. ECE measurements, at high Te, have been found to be higher or lower than those of LIDAR, depending on the specific plasma scenario. In addition, discrepancies between the peaks of the second and third harmonic ranges of the ECE spectrum have been interpreted as evidence for the presence of non-Maxwellian features in the electron distribution function. These comparisons seem to suggest that such features can be found in most of the high-performance scenarios selected in this JET database.

Impact of vaccination with SCB-2019 COVID-19 vaccine on transmission of SARS-CoV-2 infection: a household contact study in the Philippines

Background

An exploratory household transmission study was nested in SPECTRA, the phase 2/3 efficacy study of the adjuvanted recombinant protein-based COVID-19 vaccine SCB-2019. We compared occurrence of confirmed COVID-19 infections between households and household contacts of infected SPECTRA placebo or SCB-2019 recipients.

Methods

SPECTRA participants at eight study sites in the Philippines who developed rRT-PCR-confirmed COVID-19 were contacted by a study team blinded to assignment of index cases to vaccine or placebo groups to enroll in this household transmission study. Enrolled households and household contacts were monitored for three weeks using rRT-PCR and anti-SARS-CoV-2 N-antigen IgG/IgM testing to detect new COVID-19 infections.

Results

154 eligible COVID-19 index cases (51 vaccinees, 103 placebo) were included. The secondary attack rate per household for symptomatic COVID-19 infection was 0.76% (90% CI: 0.15–3.90) if the index case was a SCB-2019 vaccinee compared with 5.88% (90% CI: 3.20–10.8) for placebo index cases, a relative risk reduction (RRR) of 79% (90% CI: -28–97). The RRR of symptomatic COVID-19 per household member was similar: 84% (90% CI: 28–97). Impact on attack rates in household members if index cases were symptomatic (n = 130; RRR = 80%; 90% CI: 7–96) or asymptomatic (n = 24; RRR = 100%; 90% CI: -76–100) was measurable but the low numbers undermine the clinical significance.

Conclusions

In this prospective household contact study vaccination with SCB-2019 reduced SARS-CoV-2 transmission compared with placebo in households and in household members independently of whether index cases were symptomatic or not.

A high-resolution neutron spectroscopic camera for the SPARC tokamak based on the Jet European Torus deuterium-tritium experience

Dedicated nuclear diagnostics have been designed, developed, and built within EUROFUSION enhancement programs in the last ten years for installation at the Joint European Torus and capable of operation in high power Deuterium-Tritium (DT) plasmas. The recent DT Experiment campaign, called DTE2, has been successfully carried out in the second half of 2021 and provides a unique opportunity to evaluate the performance of the new nuclear diagnostics and for an understanding of their behavior in the record high 14 MeV neutron yields (up to 4.7 × 10¹⁸ n/s) and total number of neutrons (up to 2 × 10¹⁹ n) achieved on a tokamak. In this work, we will focus on the 14 MeV high resolution neutron spectrometers based on artificial diamonds which, for the first time, have extensively been used to measure 14 MeV DT neutron spectra with unprecedented energy resolution (Full Width at Half Maximum of ≈1% at 14 MeV). The work will describe their long-term stability and operation over the DTE2 campaign as well as their performance as neutron spectrometers in terms of achieved energy resolution and high rate capability. This important experience will be used to outline the concept of a spectroscopic neutron camera for the SPARC tokamak. The proposed neutron camera will be the first one to feature the dual capability to measure (i) the 2.5 and 14 MeV neutron emissivity profile via the conventional neutron detectors based on liquid or plastics scintillators and (ii) the 14 MeV neutron spectral emission via the use of high-resolution diamond-based spectrometers. The new opportunities opened by the spectroscopic neutron camera to measure plasma parameters will be discussed.

Lost alpha Faraday cup foil noise characterization during Joint European Torus plasma post-processing analysis

Capacitive plasma pickup is a well-known and difficult problem for plasma-facing edge diagnostics. This problem must be addressed to ensure an accurate and robust interpretation of the real signal measurements vs noise. The Faraday cup fast ion loss detector array of the Joint European Torus (JET) is particularly prone to this issue and can be used as a testbed to prototype solutions. The issue of separation and distinction between warranted fast ion signal and electromagnetic plasma noise has traditionally been solved with hardware modifications, but a more versatile post-processing approach is of great interest. This work presents post-processing techniques to characterize the signal noise. While hardware changes and advancements may be limited, the combination with post-processing procedures allows for more rapid and robust analysis of measurements. The characterization of plasma pickup noise is examined for alpha losses in a discharge from JET's tritium campaign. In addition to highlighting the post-processing methodology, the spatial sensitivity of the detector array is also examined, which presents significant advantages for the physical interpretation of fast ion losses.

A new dedicated signal processing system for gamma-ray spectrometers in high power deuterium-tritium plasma scenarios in tokamaks

The most performant deuterium-tritium (DT) plasma discharges realized by the Joint European Torus (JET) tokamak in the recent DT campaign have produced neutron yields on the order of 10¹⁸ n/s. At such high neutron yields, gamma-ray spectroscopy measurements with scintillators are challenging as events from the neutron-induced background often dominate over the signal, leading to a significant fraction of pileup events and instability of the photodetector gain along with the consequent degradation of the reconstructed spectrum. Here, we describe the solutions adopted for the tangential lanthanum bromide spectrometer installed at JET. A data acquisition system with free streaming mode digitization capabilities for the entire duration of the discharge has been used to solve dead-time related issues and a data reconstruction code with pileup recovery and photodetector gain drift restoration has been implemented for off-line analysis of the data. This work focuses on the acquired data storage and parsing, with a detailed explanation of the pileup recovery and gain drift restoration algorithms.

Fusion product measurements by nuclear diagnostics in the Joint European Torus deuterium-tritium 2 campaign (invited)

A new deuterium-tritium experimental, DTE2, campaign has been conducted at the Joint European Torus (JET) between August 2021 and late December 2021. Motivated by significant enhancements in the past decade at JET, such as the ITER-like wall and enhanced auxiliary heating power, the campaign achieved a new fusion energy world record and performed a broad range of fundamental experiments to inform ITER physics scenarios and operations. New capabilities in the area of fusion product measurements by nuclear diagnostics were available as a result of a decade long enhancement program. These have been tested for the first time in DTE2 and a concise overview is provided here. Confined alpha particle measurements by gamma-ray spectroscopy were successfully demonstrated, albeit with limitations at neutron rates higher than some 10¹⁷ n/s. High resolution neutron spectroscopy measurements with the magnetic proton recoil instrument were complemented by novel data from a set of synthetic diamond detectors, which enabled studies of the supra-thermal contributions to the neutron emission. In the area of escaping fast ion diagnostics, a lost fast ion detector and a set of Faraday cups made it possible to determine information on the velocity space and poloidal distribution of the lost alpha particles for the first time. This extensive set of data provides unique information for fundamental physics studies and validation of the numerical models, which are key to inform the physics and scenarios of ITER.

CONCERTO at APEX: Installation and first phase of on-sky commissioning

CONCERTO (CarbON CII line in post-rEionisation and ReionisaTiOn) is a large field-of-view (FoV) spectro-imager that has been installed on the Cassegrain Cabin of Atacama Pathfinder EXperiment (APEX) telescope in April 2021. CONCERTO hosts 2 focal planes and a total number of 4000 Kinetic Inductance Detectors (KID), with an instantaneous FoV of 18.6 arcminutes in the range of 130-310 GHz. The spectral resolution can be easily tuned down to 1 GHz depending on the scientific target. The scientific program of CONCERTO has many objectives, with two main programs focused on mapping the fluctuations of the [CII] line intensity in the reionisation and postreionisation epoch (4.5<z<8.5), and on studying galaxy clusters via the thermal and kinetic Sunyaev-Zel’dovich (SZ) effect. CONCERTO will also measure the dust and molecular gas contents of local and intermediate-redshift galaxies, it will study the Galactic star-forming clouds and finally it will observe the CO intensity fluctuations arising from 0.3<z<2 galaxies.

The design of the instrument, installation at APEX and current status of the commissioning phase and science verification will be presented. Also we describe the deployment and first on-sky tests performed between April and June 2021.

P–704 Does the type of ovarian stimulation scheme and dose matter when calculating the amount of gonadotropins used to obtain an egg?

Study question

Is the controlled ovarian stimulation protocol important to determine the ovarian sensitivity index (number of oocytes retrieved / total gonadotropin dose)?

Summary answer

OSI in an interesting tool in estimating the ovarian sensitivity to exogenous gonadotropins and can be adjusted when different kinds of COS procotols are used.

What is known already

In our country, Argentina, as the fertility treatments are financed by different health care insurance companies, COS protocols may vary depending on the drugs provided. The objective of our study is to assess the oocyte retrieval number in patients undergoing COS, for IVF or fertility preservation (egg freezing), on the basis of the kind of protocol and the average gonadotropin dose.

Study design, size, duration

This is a retrospective and descriptive study in which 684 cycles, performed between November 2018 and March 2020, were evaluated. Patients underwent COS for IVF or fertility preservation purposes.

Participants/materials, setting, methods

COS protocols were analysed including different parameters such as: number of mature follicles (17mm or more) the trigger day, number of oocytes retrieved, number of M2 retrieved, follicle to oocyte index (FOI), and the kind of protocol.Each of these groups were divided into four groups depending on the protocol used. Group A: FSHr; Group B: FSHr/LHr; Group C: FSHr + HMG; Group D: Clomiphene citrate + HMG. Oocyte donors and incomplete medical records were excluded

Main results and the role of chance

The total number of cycles analysed was 684. There were 135(19.7%) cycles in the under 35 age group; 340(42%) in the 35 to 39 group; 209(38%) in the older than 40 group. They were subdivided in Group A: 54(6.67%) cycles; Group B 93(11.11%) cycles; Group C 465(71.72%); Group D 72(10.5%). A total number of 11351 oocytes were retrieved, with a mean average of 4.6 +- 2.5 SD per patient. Assessment of dose of gonadotropin per oocyte retrieved in each different group: GROUP A 360IU+–38 SD; GROUP B 390IU+–43 SD; GROUP C 375IU +–44 SD; GROUP D 479+–36 SD.

Limitations, reasons for caution

This is a retrospective study. Further prospective studies and a higher sample size are needed to confirm whether the OSI is a useful tool to adjust gonadotropins doses related to an specific COS protocol and improve the oocyte pick up.

Wider implications of the findings: The main conclusion obtained was that the average dose of gonadotropin needed to obtain one mature oocyte was 360 to 390 IU. The HMG and clomiphene citrate protocol needed the highest dose of gonadotropin (479 IU) but no significant stadistical differences were observed.

Trial registration number

NA

Nanoghosts: Mesenchymal Stem cells derived nanoparticles as a unique approach for cartilage regeneration

Osteoarthritis (OA) is a chronic degenerative disease, which affects the joints and is characterized by inflammation, cartilage loss and bone changes. Nowadays, there are no treatments for OA, and current therapies are focused on relieving the symptoms. As a new therapy approach, micro and nanoparticles have been extensively explored and among all the studied particles, the use of cell-membrane-based particles is expanding. Another promising approach studied to treat OA, is the use of mesenchymal stem cells (MSCs) which play an important role modulating inflammation. We developed a novel kind of MSCs' cytoplasmic-membrane-based nanoparticles, termed nano-ghosts (NGs). Retaining MSCs' surface properties and lacking cells' internal machinery allow the NGs to have immunomodulatory capacity and to be immune-evasive while not susceptible to host-induced changes. In this study, we demonstrate NGs' ability to target cartilage tissues, in vitro and in vivo, while modulating the inflammatory process. In vivo studies demonstrated NGs ability to act as an immunomodulatory drug slowing down cartilage degeneration process. Our proof-of-concept experiments show that NGs system is a versatile nano-carrier system, capable of therapeutics loading, with targeting capabilities towards healthy and inflamed cartilage cells. Our results, along with previously published data, clearly reveal the NGs system as a promising nano-carrier platform and as a potential immunomodulatory drug for several inflammation-related diseases.

Bicuspid aortic valve disease associates with abnormal wall shear stress, viscous energy loss, and pressure drop within the ascending thoracic aorta

Introduction

We use 4D Flow MRI to (1) investigate the effects of bicuspid aortic valve (BAV) disease on downstream pressure drop (PD), wall shear stress (WSS), and viscous energy loss (EL) in the ascending aorta (AAo) and (2) explore the associations between AAo diameter and PD, WSS, and EL.

Hypothesis

BAV patients show increased PD, WSS, and EL in the AAo compared to age-matched controls

Methods

32 healthy controls (41±15 y, 10 female) and 53 BAV patients (44±16 y, 19 female) underwent cardiac MRI at 3T, inclusive of cine imaging and 4D flow. Cross sections were placed along segmented aortas at the: left ventricular outflow tract (LVOT), sinuses of Valsalva (SOV), mid-ascending aorta (MAA), and proximal to first aortic branch (AA1). Locations were analyzed for (i) net flow, (ii) aortic diameter (normalized to BSA), (iii) systolic PD (referenced to LVOT), (iv) systolic EL (measured within LVOT-AA1 volume and normalized by LVOT net flow; mW/mL), and (v) systolic WSS. Sub-vectors of WSS, axial (WSSax) and circumferential (WSScirc), were also analyzed.

Results

In comparison to controls, BAV patients showed greater PD (e.g. MAA: 9.5±8.0 vs. 2.8±2.4mmHg; p&lt;0.01), EL (0.09±0.05 vs. 0.04±0.01 mW/mL; p≤0.01), and WSScirc (e.g. MAA: 0.3±0.1 vs. 0.2±0.06 Pa; p≤0.01) throughout the AAo (Table 1 and Fig. 1). BAV patients exhibited significantly lower WSS and WSSax only at the SOV. In univariate analyses, AAo diameter was inversely correlated with WSS (R=−0.32, p&lt;0.01) and WSSax (R=−0.51, p≤0.01). In multivariate analyses, AAo diameter was associated with WSS (β=−0.36, p&lt;0.01) and WSSax (β=−0.26, p&lt;0.01).

Conclusions

BAV patients demonstrate significantly increased PD, EL, and WSScirc in the AAo, and an inverse association between AAo diameter and WSS measures.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Alberta Health Services

Truncated Nonlinear Interferometry for Quantum-Enhanced Atomic Force Microscopy

Nonlinear interferometers that replace beam splitters in Mach-Zehnder interferometers with nonlinear amplifiers for quantum-enhanced phase measurements have drawn increasing interest in recent years, but practical quantum sensors based on nonlinear interferometry remain an outstanding challenge. Here, we demonstrate the first practical application of nonlinear interferometry by measuring the displacement of an atomic force microscope microcantilever with quantum noise reduction of up to 3 dB below the standard quantum limit, corresponding to a quantum-enhanced measurement of beam displacement of 1.7  fm/sqrt[Hz]. Further, we minimize photon backaction noise while taking advantage of quantum noise reduction by transducing the cantilever displacement signal with a weak squeezed state while using dual homodyne detection with a higher power local oscillator. This approach may enable quantum-enhanced broadband, high-speed scanning probe microscopy.

126Dynamic high density functional substrate mapping improves outcomes in ventricular tachycardia ablation

Introduction

Activation and entrainment mapping of VT remains the gold standard for identifying critical sites for ablation of VT, however, this method is limited by poorly tolerated or non-sustained VT. Several substrate guided approaches have been developed, however, outcomes when comparing both methods are similar and overall success can be as low as 47%. A key element in facilitating VT is the presence of dynamic changes within the substrate which may not be evident during sinus rhythm substrate mapping, but may form a critical aspect of the tachycardia mechanism when conduction velocity slows dynamically and tissue refractory periods lengthen. These are rarely studied as part of clinical VT mapping. 

Purpose

This study aimed to investigate dynamic substrate changes to local abnormal ventricular activity (LAVA) and late potentials (LP), in relation to critical sites for VT ablation using high resolution mapping of the ventricle with the HD Grid (Abbott, Inc, USA), during short coupled singe extra stimuli from the right ventricle (RV) (Barts Sense Protocol), designed to invoke conduction delay. We hypothesized that the dynamic functional late potential mapping would improve the identification of critical substrate and ablation of these regions would improve outcomes. 

Methods

Thirty patients (age 67 +/- 9yrs, 27Male) underwent ablation. Mean ejection fraction was 25% (+/- 10%). Mapping was performed with the AdvisorTM HD Grid multipolar catheter. A bipolar voltage map was obtained during sinus rhythm (SR) and RV Sensed Protocol (SP) single extra pacing. SR and SP late potential (LP) and local abnormal ventricular activity (LAVA) maps were made and compared with critical sites for ablation, defined as sites of best entrainment or pace mapping. Ablation was then performed to critical sites and LP/LAVA identified by the SP.

Results

At a median follow up of 10 months 90% of patients were free from symptomatic ATP or ICD shocks. The median area of late potentials across the 30 patients during sinus rhythm was 6.4mm2 during sinus rhythm mapping and 19.3mm2 during sense protocol pacing (p = 0.001). The functional unmasking of LP and LAVA was seen in 26 patients and showed good correlation to critical regions of the VT circuit (sites of best entrainment or pace map). In 24 patients functionally unmasked late potentials were located within 10mm of critical regions within the mapped VT circuit, with a median distance of 8.5mm, compared to 7 patients during sinus rhythm mapping with a median distance of 22mm (p= &lt;0.001). Figure 1 demonstrates and example of the SP, where increased functional LP are seen along the mapped VT isthmus. 

Conclusion

Functional LP and LAVA can be unmasked by the sense protocol enabling better delineation of critical regions for VT ablation which may not be visible during sinus rhythm. This unique delineation of functional substrate changes combined with activation or pacemapping may improve outcomes.

Abstract Figure 1

THU0053 CONTRIBUTION OF DEFECTIVE NON-APOPTOTIC FAS SIGNALING TO IMMUNE DYSREGULATION IN AUTOIMMUNE LYMPHOPROLIFERATIVE SYNDROME (ALPS)

Background:

ALPS patients show impaired generation of humoral memory for T independent antigens whereas they generate memory for self-antigens due to impaired FAS-dependent removal of autoreactive germinal center B cells. It is known that FAS signaling via caspase activation results in cell apoptosis. However, FAS ligation may also initiate or modulate non-apoptotic signaling as shown for example by its ability to activate NF-κB. Recent data implicate a regulatory role of FAS in the modulation of mTOR signaling in ALPS double-negative T cells. Moreover, a recently described C194V FAS mutation disturbs its post-translational modification leading to impaired apoptosis induction while non-apoptotic signalling is still intact. Consequently, C194V FAS protects from the autoimmune phenotype in the murine ALPS system. This supports the view that FAS may prevent autoimmunity with other mechanisms than inducing apoptosis.

Objectives:

We hypothesize that FAS mutations impair this modulatory signaling, leading to hyper-activation of B cells. Therefore we aim to investigate non apoptotic FAS signaling in B cells derived from healthy individuals and ALPS patients.

Methods:

We studied resting and activated B cells in ALPS patients in presence or absence of FAS ligand by flow cytometry analysing relevant molecules to the CD40 signaling pathway. We used mass cytometry to perform functional phenotyping of B cells isolated from secondary lymphoid organs. Proteomic studies were performed to identify potential signaling circuits and RNA sequencing to study the consequences of FAS signaling on B cell fate.

Results:

In CD40L activated B cells, FAS signaling results in specific modulation of the mTOR signaling pathway. This modulation is absent in ALPS derived B cells. In line with these data germinal center B cells and plasmablast from secondary lymphoid organs of ALPS patients show hyperactive mTOR signaling pathway. Proteomic studies identify a circuit that links FAS to the phosphatase PTEN via DAXX and the deubiquitinase USP7.

Conclusion:

We describe a new role of FAS in the regulation of B cell activation. Defects in FAS signaling in ALPS contribute to dysregulation of the mTOR signaling pathway and disturbed B cell development.

Disclosure of Interests:

None declared

1102 Relationship Between Emotional Distress And Sleep Duration Among Hispanics Using The 2018 National Health Interview Survey Dataset

Introduction

Although Hispanics experience a high level of shorter sleep duration (&lt; 7 hrs./24 period), a clear mechanism or cause is lacking. Previous research indicate that emotional distress may explain the burden of shorter sleep among blacks. Applying these findings to Hispanics, we investigated whether emotional distress explains the burden of short sleep duration (&lt; 7 hrs.) among Hispanics and if this relationship varies by sex

Methods

We used data from the 2018 National Health Interview Survey (NHIS) dataset, a nationally representative sample, in which only Hispanic ethnicity participants (N=3,091) were analyzed. Average sleep duration was self-reported and measured in hours. Emotional distress was measured using Kessler 6, which measures how an individual felt over the past 30 days: nervous, hopeless, restless/fidgety, depressed, effortful and worthless. To assess the association between short sleep duration and emotional distress, we performed Pearson correlation, hierarchical regression analyses, and stratified this relationship by sex to determine if this relationship differed between males and females, adjusting for covariates.

Results

Of the total sample of 3,091 Hispanics, 1,762 were female, and 1,329 were male. Sleep duration and emotional distress were negatively correlated among females (r = -.27, p &lt;.001) and males (r=-.18, p &lt;.001). Among Hispanic females, sleep duration significantly predicted emotional distress, β = -.27, t = -11.60, p &lt;.001, and explained a significant portion of variance in emotional distress, R2 = .07, F= 134.63, p &lt;.001. While, among Hispanic males, sleep significantly predicted emotional distress (β = -.18, t =-6.5, p &lt;.001) and explained a significant portion of the variance in emotional distress (R2 = .03, F= 42.37, p &lt;.001).

Conclusion

Our findings indicate that a negative sleep-ED relationship, suggesting that shorter sleep was predictive of higher levels of emotional distress among Hispanics and that this relationship is greater among Hispanic females, compared males.

Support

K01HL135452, R01MD007716, R01HL142066, and K07AG052685

1189 Recruiting, Training, And Implementing Sleep Health Educators In Community-based Research To Improve Sleep Health

Introduction

Adherence to OSA assessment and treatment is low among racial/ethnic minorities, particularly among blacks. Navigating patients along the continuum of care from assessment to treatment adherence requires motivation, social support, and self-efficacy. Previous studies indicate that community health educators can provide motivation, social support, and skills to patients to better navigate the complex OSA care continuum. However, recruiting, training, and implementing sleep health educators in clinical or research settings is complex. For the current study, we describe how we recruit, train, and implement sleep health educators in research and clinical settings and assess what makes a sleep health educator successful.

Methods

We recruited and trained twenty-five self-identified black sleep health educators for a randomized clinical trial (R01MD007716) focused on increasing OSA assessment and treatment adherence among blacks. During recruitment, we assessed key personality attributes that translate to being an effective sleep health educator, via behavioral and personality surveys, focused groups, and process forms filled out by educators. Sleep health educators underwent an 8-week training program on sleep health and motivational interviewing. In order to be certified, sleep health educators had to pass a written and scenario-based assessment. During the implementation phase of the trial, we assessed how many interviews each health educator conducted and whether individual characteristics were related to how many interviews.

Results

Of the trained educators, 80% were female, ranging from 25 to 58 years old. They all completed at least high school. All educators rated the program highly and were very satisfied with dispensing tailored sleep health education. Educators who displayed the highest knowledge about sleep health, provided frequent emotional and strategic support, committed to helping their assigned participants, and who rated their rapport highly with their assigned participants were most effective in getting their participant to adhere to OSA assessment and treatment.

Conclusion

Sleep health educators can be vital to increasing OSA assessment and treatment adherence among blacks. In order to ensure success, sleep health educators must undergo a thorough recruitment, training, and implementation and dissemination process.

Support

K01HL135452, R01MD007716, R01HL142066, K01HL135452,and K07AG052685

0078 Influence of Light on Brain Activity Upon Waking From Slow Wave Sleep

Introduction

Waking from sleep is associated with reduced alertness due to sleep inertia. Light acutely improves alertness during sleep deprivation. In this study we assessed the influence of light on brain activity and connectivity after waking from slow wave sleep (SWS).

Methods

Twelve participants kept an actigraphy-confirmed stable sleep schedule with 8.5 hours for five nights and five hours for one night prior to an overnight laboratory visit. Participants completed two three-minute Karolinska Drowsiness Tests (KDT) before going to bed at their habitual bedtime. They were monitored continuously using high-density EEG (32-channel; Brain Products GmbH). Participants were woken twice and exposed to red light (0.01 melanopic-lux; control) or blue-enriched light (63.62 melanopic-lux) for one hour, in a randomized order, following at least five minutes of SWS. EEG artifact were removed algorithmically and the spectral composition of each electrode (i.e., fast fourier transform, FFT) and effective connectivity (i.e., partial directed coherence, PDC) between each electrode were estimated. A graphical analysis was conducted to extract features relevant to the facilitation of efficient communication between electrodes. All data were averaged within frequency bins of interest that correspond to delta (1-3Hz), theta (4-7Hz), alpha (8-12Hz), and beta (13-25Hz) bands and expressed relative to the pre-sleep baseline.

Results

Compared to the pre-sleep baseline, participants exposed to blue-enriched light experienced reduced theta and alpha activity; however, these results were not significantly different from the control. In contrast, the communication of frontal electrodes significantly increased across all frequency bands compared to the control, and this effect was most prominent in the alpha (t(11)=3.80, p=.005) and beta bands (t(11)=3.92, p=.004).

Conclusion

Exposure to blue-enriched light immediately after waking from SWS may accelerate the process of waking and help to improve alertness by facilitating communication between brain regions. Future analyses will explore the temporal persistence and granularity of the communicative properties associated with this response.

Support

Naval Postgraduate School Grant. NASA Airspace Operations and Safety Program, System-Wide Safety Project.

Outcome of ACHD patients with non-inducible versus inducible IART undergoing cavo-tricuspid isthmus ablation: the role of empiric ablation

PURPOSE

Catheter ablation for supraventricular tachycardia (SVT) in adults with congenital heart disease (ACHD) is an important therapeutic option. Cavo-tricuspid isthmus (CTI)-dependent intraatrial re-entrant tachycardia (IART) is common. However, induction of sustained tachycardia at the time of ablation is not always possible. We hypothesised that performing an empiric CTI line in case of non-inducibility leads to good outcomes. Long-term outcomes of empiric versus entrained CTI ablation in ACHD patients were examined.

METHODS

Retrospective, single-centre, case-control study over 7 years. Arrhythmia-free survival after empiric versus entrained CTI ablation was compared.

RESULTS

Eighty-seven CTI ablations were performed in 85 ACHD patients between 2010 and 2017. The mean age of the cohort was 43 years and 48% were male. Underlying aetiology included ASD (31%), VSD (11.4%), AVSD (9.1%), AVR (4.8%), Fallot's (18.4%), Ebstein's (2.3%), Fontan's palliation (9.2%) and atrial switch (13.8%). CTI-dependent IART was entrained in 59 patients whereas it was non-inducible in 28. The latter had an empiric CTI ablation. Forty-three percent of procedures were performed under general anaesthesia. There were no reported procedural complications. There was no significant difference in the mean procedure or fluoroscopy times between the groups (empiric vs entrained CTI; 169.1 vs 183.3 and 28.1 vs 19.9 min). Arrhythmia-free survival was 64.3% versus 72.8% (p value 0.44) in the empiric and entrained groups at 21 months follow-up.

CONCLUSIONS

Long-term outcomes after empiric and entrained CTI ablation for IART in ACHD patients are comparable. This is a safe and effective therapeutic option. In the case of non-inducibility of IART, an empiric CTI line should be considered in this cohort.

Determination of Fluoride in Wine by Fluoride Selective Ion Electrode, Standard Addition Method: Collaborative Study

The accuracy, precision, and reproducibility of a rapid method for determination of fluoride in wine, using a fluoride selective ion electrode, were established by a collaborative study involving 12 laboratories, 5 in Europe and 7 in the United States. The laboratories assayed 6 Youden pairs of fluo-ride-fortified, red and white wine samples with fluoride concentrations ranging from 0.2 to 3.0 mg/L. The relative standard deviations of repeatability ranged from 1.94 to 4.88%; relative standard deviations of reproducibility ranged from 4.15 to 18.40%. HORRAT values ranged from 0.30 to 0.97. The average recovery was 99.97%. Based on the statistical results of this collaborative study, the Study Director recommends that this method be adopted First Action.