Non-invasive suppression of the human nucleus accumbens (NAc) with transcranial focused ultrasound (tFUS) modulates the reward network: a pilot study

Background

The nucleus accumbens (NAc) is a key node of the brain reward circuit driving reward-related behavior. Dysregulation of NAc has been demonstrated to contribute to pathological markers of addiction in substance use disorder (SUD) making it a potential therapeutic target for brain stimulation. Transcranial focused ultrasound (tFUS) is an emerging non-invasive brain stimulation approach that can modulate deep brain regions with a high spatial resolution. However, there is currently no evidence showing how the brain activity of NAc and brain functional connectivity within the reward network neuromodulated by tFUS on the NAc.

Methods

In this pilot study, we carried out a single-blind, sham-controlled clinical trial using functional magnetic resonance imaging (fMRI) to investigate the underlying mechanism of tFUS neuromodulating the reward network through NAc in ten healthy adults. Specifically, the experiment consists of a 20-min concurrent tFUS/fMRI scan and two 24-min resting-state fMRI before and after the tFUS session.

Results

Firstly, our results demonstrated the feasibility and safety of 20-min tFUS on NAc. Additionally, our findings demonstrated that bilateral NAc was inhibited during tFUS on the left NAc compared to sham. Lastly, increased functional connectivity between the NAc and medial prefrontal cortex (mPFC) was observed after tFUS on the left NAc, but no changes for the sham group.

Conclusion

Delivering tFUS to the NAc can modulate brain activations and functional connectivity within the reward network. These preliminary findings suggest that tFUS could be potentially a promising neuromodulation tool for the direct and non-invasive management of the NAc and shed new light on the treatment for SUD and other brain diseases that involve reward processing.

Deintensification of potentially inappropriate medications amongst older frail people with type 2 diabetes: Protocol for a cluster randomised controlled trial (D-MED study)

AIMS

Amongst elderly people with type 2 diabetes (T2D) over prescribing can result in emergency ambulance call-outs, falls and fractures and increased mortality, particularly in frail patients. Current clinical guidelines, however, remain focused on medication intensification rather than deintensification where appropriate. This study aims to evaluate the effectiveness of an electronic decision-support system and training for the deintensification of potentially inappropriate medications amongst older frail people with T2D, when compared to 'usual' care at 12-months.

METHODS

This study is an open-label, multi-site, two-armed pragmatic cluster-randomised trial. GP practices randomised to the 'enhanced care' group have an electronic decision support system installed and receive training on the tool and de-intensification of diabetes medications. The system flags eligible patients for possible deintensification of diabetes medications, linking the health care professional to a clinical algorithm. The primary outcome will be the number of patients at 12-months who have had potentially inappropriate diabetes medications de-intensified.

RESULTS

Study recruitment commenced in June 2022. Data collection commenced in January 2023. Baseline data have been extracted from 40 practices (3145 patients).

CONCLUSIONS

Digital technology, involving computer decision systems, may have the potential to reduce inappropriate medications and aid the process of de-intensification.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number: ISRCTN53221378. Available at: https://www.isrctn.com/ISRCTN53221378.

Exploring software navigation tools for liver tumour angiography: a scoping review

INTRODUCTION

Liver cancer presents a growing global health concern, necessitating advanced approaches for intervention. This review investigates the use and effectiveness of software navigation in interventional radiology for liver tumour procedures.

METHODS

In accordance with Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, a scoping review was conducted of the literature published between 2013 and 2023 sourcing articles through MEDLINE, Scopus, CINAHL and Embase. Eligible studies focused on liver cancer, utilised cone-beam computed tomography (CBCT), and employed software for intervention. Twenty-one articles were deemed eligible for data extraction and analysis.

RESULTS

Categorised by type, software applications yielded diverse benefits. Feeder detection software significantly enhanced vessel identification, reducing non-target embolisation by up to 43%. Motion correction software demonstrated a 20% enhancement in image quality, effectively mitigating breathing-induced motion artefacts. Liver perfusion software facilitated efficient tumour targeting while simultaneously reducing the occurrence of side effects. Needle guide software enabled precise radiofrequency ablation needle placement. Additionally, these software applications provided detailed anatomical simulations. Overall, software integration resulted in shorter procedures, reduced radiation exposure and decreased contrast media usage.

CONCLUSION

This scoping review highlights the innovative yet relatively underexplored role of software navigation for liver tumour procedures. The integration of software applications not only enhances procedural efficiency but also bolsters operator confidence, and contributes to improved patient outcomes. Despite the current lack of uniformity and standardisation, these software-driven advancements hold significant promise for transforming liver tumour interventions. To realise these benefits, further research is needed to explore the clinical impact and optimal utilisation of software navigation tools in interventional radiology.

Calcium Channel Blocker Overdose: What Role Does Extracorporeal Membrane Oxygenation Have in Support? A Systematic Review of the Literature

Extracorporeal membrane oxygenation (ECMO) has had increasing prevalence and indications in the last decade. Calcium channel blocker overdose (CCBOD) can lead to significant cardiopulmonary dysfunction and has also increased in recent years. CCBOD results in cardiac depression, vasoplegia, and hyperglycemia. Expert consensus recommends treatment with calcium, high-dose insulin, inotropes, and vasopressors. Our systematic review evaluated when to initiate ECMO in the CCBOD population and the mortality rate associated with use. Electronic literature review identified all relevant studies for CCBOD and ECMO. PRISMA guidelines for systematic review were followed. Three independent authors reviewed abstracts and full texts, and only CCB ingestion without polypharmacy was included. Two authors independently collected data, which included demographics, current medical treatments, ECMO type, and survival. From 314 abstracts, 25 papers were included with a median publication year of 2019. Twenty-six patients were included with an average age of 32.7 years and 42%/58% male/female. Average time on ECMO 4.3 days. VA and VV ECMO use were 92.3% and 7.7%, respectively, and 84.6% of patients survived to hospital discharge. Before ECMO, most patients received 4-5 medical treatments (53.8%). Our systematic review demonstrates ECMO is a newly used, yet valuable therapy for CCBOD when medical treatment fails. Survival to discharge after ECMO for CCBOD is substantially higher than standard VV or VA ECMO. Medical management is still the mainstay therapy for CCBOD, but we show that a persistently unstable patient may benefit from prompt evaluation at an ECMO center for treatment.

Sustained long-term disease correction in a murine model of MPSII following stem cell gene therapy

Mucopolysaccharidosis type II (MPSII) is a pediatric lysosomal storage disease caused by deficiencies in the IDS (iduronate-2-sulfatase) gene resulting in accumulation of glycosaminoglycans, multisystem disease, and profound neurodegeneration in severe forms. Although enzyme replacement therapy is available for somatic forms of disease, the inability of native IDS to pass the blood-brain barrier renders it ineffective for the brain. We previously demonstrated the short-term efficacy of a brain-targeted hematopoietic stem cell gene therapy approach to treat MPSII mice using lentiviral IDS fused to the blood-brain-barrier-crossing peptide ApoEII (IDS.ApoEII) in comparison with a lentivirus expressing native IDS and an unmanipulated bone marrow transplant. Here we evaluated the longevity of disease correction for 12-16 months following treatment. We observed sustained IDS enzyme activity in organs of long-term IDS.ApoEII-treated MPSII mice, similar to those analyzed 6 months post-treatment, with continued clearance of storage material in the brain and peripheral organs, maintained correction of astrogliosis, microgliosis, and correction of altered cytokines and chemokines. IDS.ApoEII also significantly reduced retinal atrophy, characteristic of MPSII. Overall, IDS.ApoEII resulted in systemic prevention of the MPSII phenotype, with no observed toxicity following treatment. This provides evidence of the sustained efficacy and safety of this treatment ahead of a recently opened clinical trial.

Screening women for distress during pregnancy: the impact of including 'Possibly' as a response option

OBJECTIVES

To investigate the impact of including the response option of 'Possibly' in the Distress question on the Matthey Generic Mood Questionnaire (MGMQ) during antenatal emotional health screening in English-speaking women.

BACKGROUND

Some distress screening questions only allow respondents to choose between 'Yes' or 'No' to the presence of distress. The MGMQ, however, allows respondents to chose between 'Yes', 'Possibly', or 'No', which may be preferable if a participant is reluctant to state she definitely feels distressed.

METHOD

In Study 1, women undergoing routine antenatal psychosocial screening were allocated to either completing the MGMQ Distress question with the usual three-option response format of 'Yes, Possibly, No' (N = 960), or just a 'Yes, No' response format (N = 771). The proportion of responses were compared in each group, as were the proportion then screening positive on the MGMQ's Bother question. In Study 2, women (N = 113) attending routine antenatal clinic appointments were asked about their preference between these response formats.

RESULTS

Including 'Possibly' resulted in only a slight increase in the proportion giving a positive response to the Distress question, and then also screening positive on the Bother question. In Study 2, a substantial majority of women (80%) preferred having 'Possibly' in the response options.

CONCLUSION

While the impact of including 'Possibly' is small, it allows for more women to communicate how they are feeling on the full MGMQ. Given the large majority of women preferring having 'Possibly' included, we believe that the Distress Question is enhanced by having this as a response option.

Pathways to interoperable electronic patient records for health and social care: Part 1: for those involved directly in care

Here, we illustrate the clinical and technical implementation of interoperable health data for direct care from the viewpoint of practicing clinicians using examples from primary care. Interoperability allows people involved in the provision and receipt of care to seamlessly exchange and use the coded, free text and documentary data they need to inform care decisions. The pathway toward NHS interoperability to support direct care has been long, but substantial progress has been made. GP computer systems and data-recording standards, national infrastructure and hospital trusts have come a long way on the journey to fully interoperable records. GPs can now receive and utilise laboratory data; via GP2GP, they can transfer full electronic patient records when patients move practice; share health data with other health organisations through GP Connect to support patient care; and provide patients with online access to their full GP record, a cornerstone of person-centred care. Here, we describe the effective technical assets and standards that have been developed to enable electronic patient record data to be shared reliably and securely.

Disease-specific selective vulnerability and neuroimmune pathways in dementia revealed by single cell genomics

The development of successful therapeutics for dementias requires an understanding of their shared and distinct molecular features in the human brain. We performed single-nuclear RNAseq and ATACseq in Alzheimer disease (AD), Frontotemporal degeneration (FTD), and Progressive Supranuclear Palsy (PSP), analyzing 40 participants, yielding over 1.4M cells from three brain regions ranging in vulnerability and pathological burden. We identify 35 shared disease-associated cell types and 14 that are disease-specific, replicating those previously identified in AD. Disease - specific cell states represent molecular features of disease-specific glial-immune mechanisms and neuronal vulnerability in each disorder, layer 4/5 intra-telencephalic neurons in AD, layer 2/3 intra-telencephalic neurons in FTD, and layer 5/6 near-projection neurons in PSP. We infer intrinsic disease-associated gene regulatory networks, which we empirically validate by chromatin footprinting. We find that causal genetic risk acts in specific neuronal and glial cells that differ across disorders, primarily non-neuronal cells in AD and specific neuronal subtypes in FTD and PSP. These data illustrate the heterogeneous spectrum of glial and neuronal composition and gene expression alterations in different dementias and identify new therapeutic targets by revealing shared and disease-specific cell states.

Association of Dual-Task Gait Cost and White Matter Hyperintensity Burden Poststroke: Results From the ONDRI

BACKGROUND

Acute change in gait speed while performing a mental task [dual-task gait cost (DTC)], and hyperintensity magnetic resonance imaging signals in white matter are both important disability predictors in older individuals with history of stroke (poststroke). It is still unclear, however, whether DTC is associated with overall hyperintensity volume from specific major brain regions in poststroke.

METHODS

This is a cohort study with a total of 123 older (69 ± 7 years of age) participants with history of stroke were included from the Ontario Neurodegenerative Disease Research Initiative. Participants were clinically assessed and had gait performance assessed under single- and dual-task conditions. Structural neuroimaging data were analyzed to measure both, white matter hyperintensity (WMH) and normal appearing volumes. Percentage of WMH volume in frontal, parietal, occipital, and temporal lobes as well as subcortical hyperintensities in basal ganglia + thalamus were the main outcomes. Multivariate models investigated associations between DTC and hyperintensity volumes, adjusted for age, sex, years of education, global cognition, vascular risk factors, APOE4 genotype, residual sensorimotor symptoms from previous stroke and brain volume.

RESULTS

There was a significant positive global linear association between DTC and hyperintensity burden (adjusted Wilks' λ = .87, P = .01). Amongst all WMH volumes, hyperintensity burden from basal ganglia + thalamus provided the most significant contribution to the global association (adjusted β = .008, η² = .03; P = .04), independently of brain atrophy.

CONCLUSIONS

In poststroke, increased DTC may be an indicator of larger white matter damages, specifically in subcortical regions, which can potentially affect the overall cognitive processing and decrease gait automaticity by increasing the cortical control over patients' locomotion.

Pandemic preparedness of diagnostic radiographers during COVID-19: A scoping review

INTRODUCTION

As chest imaging is a tool for detecting coronavirus disease 2019 (COVID-19), diagnostic radiographers are a key component of the frontline workforce. Due to its unforeseen nature, COVID-19 has challenged radiographers' preparedness in combating its effects. Despite its importance, literature specifically investigating radiographers' readiness is limited. However, the documented experiences are prognostic of pandemic preparedness. Hence, this study aimed to map this literature by addressing the question: 'what does the existing literature reveal about the pandemic preparedness of diagnostic radiographers during COVID-19?'.

METHODS

Using Arksey and O'Malley's framework, this scoping review searched for empirical studies in MEDLINE, Embase, Scopus, and CINAHL. Consequently, 970 studies were yielded and underwent processes of deduplication, title and abstract screening, full-text screening, and backward citation searching. Forty-four articles were deemed eligible for data extraction and analysis.

RESULTS

Four themes that reflected pandemic preparedness were extrapolated: infection control and prevention, knowledge and education, clinical workflow, and mental health. Notably, the findings highlighted pronounced trends in adaptation of infection protocols, adequate infection knowledge, and pandemic-related fears. However, inconsistencies in the provision of personal protective equipment, training, and psychological support were revealed.

CONCLUSION

Literature suggests that radiographers are equipped with infection knowledge, but the changing work arrangements and varied availability of training and protective equipment weakens their preparedness. The disparate access to resources facilitated uncertainty, affecting radiographers' mental health.

IMPLICATIONS FOR PRACTICE

By reiterating the current strengths and weaknesses in pandemic preparedness, the findings can guide clinical practice and future research to correct inadequacies in infrastructure, education, and mental health support for radiographers in the current and future disease outbreaks.

Comparison of image quality assessments between interventional radiographers and interventional radiologists using digital subtraction angiography

Purpose

The aim of our study was to compare the image quality assessments of vascular anatomy between interventional radiographers and interventional radiologists using digital subtraction angiography (DSA) runs acquired during an interventional radiology procedure.

Approach

Visual grading characteristics (VGC) analysis was used to assess image quality by comparing two groups of images, where one group consisted of procedures in which radiation dose was optimized (group A, n = 10 ) and one group where dose optimization was not performed (group B, n = 10 ). The radiation dose parameters were optimized based on theoretical and empirical evidence to achieve radiation dose reductions during uterine artery embolization procedures. The two observer groups comprised of interventional radiologists ( n = 4 ) and interventional radiographers ( n = 4 ). Each observer rated the image quality of 20 DSA runs using a five-point rating scale.

Results

The VGC analysis produced an area under the VGC curve (AUC VGC ) of 0.55 for interventional radiographers ( P = 0.61 ) and AUCVGC of 0.52 for interventional radiologists ( P = 0.83 ). The optimization of radiation dose parameters demonstrated a reduction in kerma-area product by 35% ( P = 0.026 , d = 0.5 ) and reference air kerma (Ka, r ) by 43% ( P = 0.042 , d = 0.5 ) between group A and group B.

Conclusions

VGC analysis indicated that the image quality assessments of interventional radiographers were comparable with interventional radiologists, where a reduction in radiation dose revealed no effect on both observer groups regarding their image quality assessment of vascular anatomy.

The Influence of Atmospheric Oxygen Content on the Mechanical Properties of Selectively Laser Melted AlSi10Mg TPMS-Based Lattice

Selective Laser Melting (SLM) is an emerging Additive Manufacturing (AM) technique for the on-demand fabrication of metal parts. The mechanical properties of Selectively Laser Melted (SLMed) parts are sensitive to oxygen concentration within the SLM build chamber due to the formation of oxides, which may lead to various negative consequences. As such, this work explores the influence of SLM atmospheric Oxygen Content (OC) on the macroscopic mechanical properties of SLMed AlSi10Mg bulk material and Triply Periodic Minimal Surface (TPMS) lattices namely primitive, gyroid, and diamond. Standard quasi-static tensile and crushing tests were conducted to evaluate the bulk properties of AlSi10Mg and the compressive metrics of TPMS-lattices. Two oxygen concentrations of 100 ppm and 1000 were used during the SLM fabrication of the experimental specimens. The tensile test data revealed a small influence of the oxygen content on the bulk properties. The low oxygen concentration improved the elongation while slightly reduced the ultimate tensile strength and yield stress. Similarly, the influence of the oxygen content on the compressive responses of TPMS-lattices was generally limited and primarily depended on their geometrical configuration. This study elucidates the role of SLM atmospheric oxygen content on the macroscopic behaviour of SLMed AlSi10Mg parts.

Electrical Conductivity of Additively Manufactured Copper and Silver for Electrical Winding Applications

Efficient and power-dense electrical machines are critical in driving the next generation of green energy technologies for many industries including automotive, aerospace and energy. However, one of the primary requirements to enable this is the fabrication of compact custom windings with optimised materials and geometries. Electrical machine windings rely on highly electrically conductive materials, and therefore, the Additive Manufacturing (AM) of custom copper (Cu) and silver (Ag) windings offers opportunities to simultaneously improve efficiency through optimised materials, custom geometries and topology and thermal management through integrated cooling strategies. Laser Powder Bed Fusion (L-PBF) is the most mature AM technology for metals, however, laser processing highly reflective and conductive metals such as Cu and Ag is highly challenging due to insufficient energy absorption. In this regard, this study details the 400 W L-PBF processing of high-purity Cu, Ag and Cu-Ag alloys and the resultant electrical conductivity performance. Six Cu and Ag material variants are investigated in four comparative studies characterising the influence of material composition, powder recoating, laser exposure and electropolishing. The highest density and electrical conductivity achieved was 88% and 73% IACS, respectively. To aid in the application of electrical insulation coatings, electropolishing parameters are established to improve surface roughness. Finally, proof-of-concept electrical machine coils are fabricated, highlighting the potential for 400 W L-PBF processing of Cu and Ag, extending the current state of the art.

An optimized scheme for detecting magneto-optic effects in ultrathin films with Sagnac interferometry

Sagnac interferometry is advantageous in measuring time-reversal-symmetry breaking effects in ferromagnetic and antiferromagnetic materials as it suppresses time-reversal symmetric birefringent effects that are ubiquitous and often overwhelming in optical detection systems. When its sensitivity is limited only by the amplifier noise in the photo-detector, one needs to optimize the optical power that returns to the detector. We demonstrate an experimental scheme that maximizes the returning optical power in a Sagnac interferometry when detecting the magneto-optic effect in ultrathin films. In this scheme, the optical beam bearing the Faraday effect on a thin film is reflected at a second surface coated with a highly reflective gold film. The gold film increases the returned optical power by a factor of 4-5. For a normal-incidence Sagnac interferometer, this scheme yields an increase in the signal-to-noise ratio by the same factor. For an oblique-incidence Sagnac interferometer, this scheme should yield an increase in the signal-to-noise ratio by a factor of 20-25. For illustration, this scheme is used to measure magnetization curves and Kerr rotation images of 4.5-unit-cell thick SrRuO₃(001) grown on SrTiO₃(001).

A Comparison of Inhaled Epoprostenol in Patients With Acute Respiratory Distress Syndrome and COVID-19-Associated Acute Respiratory Distress Syndrome

Introduction

Acute respiratory distress syndrome (ARDS) and coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (CARDS) are both characterized by non-cardiogenic pulmonary edema and severe hypoxemia that leads to a high percentage of patients suffering in-hospital mortality. Mechanistically, inhaled epoprostenol (iEPO) has shown a role in the treatment of ARDS and CARDS but little data are available directly comparing the two disease processes. Due to the lack of evidence of iEPO in ARDS and CARDS, the authors sought to compare the pulmonary effects of iEPO for mechanically ventilated patients with CARDS against a case match control of those with ARDS.

Methods

A retrospective cohort of all patients receiving iEPO between January 1, 2020, and February 22, 2022, was reviewed. Patients with ARDS were case-matched in a 2:1 allocation ratio of CARDS to ARDS by the number of medical comorbidities and age +/- 5 years. Clinical data collected included patient demographics, laboratory values, ventilator settings, length of hospitalization, and 28-day mortality. Comparisons of the effectiveness of iEPO between ARDS and CARDS were conducted using the chi-squared statistic for categorical variables and the Mann-Whitney statistic for continuous variables.

Results

A total of 72 patients were included in the final analysis, with 24 having ARDS and 48 CARDS. The number of medical comorbidities was no different for patients with ARDS or CARDs (p = 0.18), though the frequency of patients diagnosed with coronary artery disease (p=0.007), congestive heart failure (p=0.003), chronic obstructive pulmonary disease (p=0.004), and pulmonary hypertension (p=0.004) did vary between the two groups. A moderate but non-significant difference in pre-iEPO partial pressure of oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) ratio was noted between the groups (0.74 vs 0.65; p=0.33). Following iEPO treatment, patients with ARDS showed a greater PaO₂/FiO₂ ratio than those with CARDS (0.87 vs 0.70; p=0.02). CARDS patients who received iEPO had a longer length of stay as compared to those with ARDS (17.5 vs 12.5 days; p=0.01). However, no difference was noted in 28-day mortality between the two groups (14 vs 34; p=0.29).

Conclusion

In this small sample from a single community hospital, a statistically significant improvement in the PaO₂/FiO₂ ratio was noted for both those with ARDS and CARDS. However, those with CARDS who were given iEPO had a longer length of stay without a significant difference in mortality as compared to those with traditional ARDS.

Abstract 167: Pre-clinical characterization of a novel series of FGFR2 selective inhibitors with potency against clinically relevant mutations

The fibroblast growth factor receptor (FGFR) family of protein tyrosine kinases plays a role in many physiological processes including angiogenesis and wound healing. FGFR mutations, fusions, rearrangements, and amplifications have been linked to the pathogenesis of multiple tumor types. For example, approximately 10-15% of patients with intrahepatic cholangiocarcinoma have FGFR2 fusions, and amplification of FGFR2 is prevalent in gastric cancer and implicated in tumor growth. Approved FGFR inhibitors produce responses in patients that harbor FGFR genetic alterations but show reduced activity against key mutations (e.g., V565, N550, etc.). These pan-FGFR inhibitors also frequently show dose-limiting toxicities including hyperphosphatemia which can be linked to the inhibition of FGFR1. To address these issues, a novel series of FGFR inhibitors that are potent and selective reversible inhibitors of FGFR2 with selectivity over FGFR1 have been identified. This series also maintains activity against clinically relevant mutations in the FGFR2 protein. Inhibition of cellular FGFR phosphorylation was measured using engineered cell lines to demonstrate that the inhibitors target both wild-type FGFR2 and activating FGFR2 mutations while sparing FGFR1. In addition, CDX tumor models showed in vivo target engagement and FGFR isoform selectivity. Herein, the in vitro and in vivo characterization of a representative selective reversible FGFR2 inhibitor is described.

Citation Format: John Fischer, Karyn Bouhana, Mark J. Chicarelli, Josh Dahlke, Brad Fell, Jennifer Fulton, Anna Guarnieri, Ravi Jalluri, Amber Johnson, Brent Mclean, Max Mejia, Rob Rieger, John Robinson, Mareli Rodriguez, Francis Sullivan, Yang Wang, Shannon Winski, Yeyun Zhou. Pre-clinical characterization of a novel series of FGFR2 selective inhibitors with potency against clinically relevant mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 167.

Abstract 147: Bezuclastinib is a differentiated KIT inhibitor that exhibits unique selectivity to KIT A-loop mutations, minimal brain penetration, and favorable pharmacokinetic properties in preclinical models

KIT is a well characterized oncogenic driver, mutated in up to 80% of gastro-intestinal stromal tumors (GIST). Front-line imatinib is effective in many patients but durable responses in the setting of imatinib failure are rarely achieved due to complex secondary mutations that arise in the KIT ATP-binding pocket (exons 13/14) or the activation (A)loop (exons 17/18). Second-line sunitinib is active against exon 13/14 mutations but not A-loop mutations and identifying inhibitors that target the spectrum of possible mutations without incurring off-target toxicities related to broad-spectrum kinase inhibition has been challenging. Bezuclastinib (CGT9486) is a novel type I tyrosine kinase inhibitor that was designed as a potent and selective inhibitor of KIT A-loop mutations to address this unmet medical need. Herein, we present nonclinical data on the differentiated selectivity profile of bezuclastinib compared with other KIT inhibitors. We show that bezuclastinib is a low nanomolar inhibitor of KIT A-loop mutants which uniquely avoids targeting closely related kinases with known liabilities (e.g., PDGFRA, PDGFRB, CSF1R, and KDR) versus other approved inhibitors. In vivo pharmacokinetic/pharmacodynamic (PKPD) relationships have been evaluated utilizing either HMC1.2 human mast cell leukemia tumors for KIT phosphorylation or a Ba/F3-KIT-D816V splenomegaly model. In these models, plasma exposure associated with 50% reduction in splenomegaly or KIT phosphorylation was observed at 3-10 mg/kg/day corresponding to exposures 1.5-2.2 µg∙hr/mL. This correlated well with plasma exposure required to cause significant tumor growth inhibition in a GIST patient-derived xenograft model harboring an A-loop mutation (~1.3 µg∙hr/mL). Maximal efficacy in the PKPD models and tumor regression in GIST disease models was observed in exposure ranges of 19-36 or 11-44 µg∙hr/mL, respectively, which corresponds to clinically reached exposures in a recent GIST combination study of bezuclastinib with sunitinib. Importantly, in nonclinical studies, we also show that bezuclastinib has minimal brain penetration, a preferred feature of an anti-KIT molecule due to CNS-related adverse events observed in this targeted class. We present a tissue distribution study which demonstrates a brain:plasma ratio <0.1 following a 3-day administration at a dose that correlates with clinical exposure. This attractive selectivity and nonclinical safety profile, combined with early clinical data in advanced solid tumors, supports the potential for a best-in-class KIT inhibitor. Bezuclastinib is currently under clinical investigation in advanced SM (Phase 2, Apex NCT04996875), non-advanced SM (Phase 2, Summit), and imatinib-resistant GIST (Phase 3, Peak).

Citation Format: Anna Guarnieri, Karyn Bouhana, LouAnn Cable, Rob Rieger, Leyla Haygood, John Robinson, Shannon Winski. Bezuclastinib is a differentiated KIT inhibitor that exhibits unique selectivity to KIT A-loop mutations, minimal brain penetration, and favorable pharmacokinetic properties in preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 147.

OP0190 COMPREHENSIVE GENETIC AND FUNCTIONAL ANALYSES OF Fc GAMMA RECEPTORS EXPLAIN RESPONSE TO RITUXIMAB THERAPY FOR AUTOIMMUNE RHEUMATIC DISEASES

Background

Rituximab is widely used to treat rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) but clinical response varies. Efficacy is determined by the efficiency of depletion, which may depend on a variety of Fc gamma receptor (FcγR)-dependent mechanisms. Previous research was limited by complexity of the FCGR locus, not integrating copy number variation with functional SNP, and small sample size.

Objectives

The study objectives were to assess the effect of the full range of FcγRs variants on depletion, clinical response and functional effect on NK-cell-mediated killing in two rheumatic diseases with a view to personalised B-cell depleting therapies.

Methods

A prospective longitudinal cohort study was conducted in 873 patients [RA=611; SLE=262] from four cohorts (BSRBR-RA and BILAG-BR registries, Leeds RA and Leeds SLE Biologics). For RA, the outcome measures were 3C-DAS28CRP and 2C-DAS28CRP at 6 (+/-3) months post-rituximab (adjusted for baseline DAS28). For SLE, major clinical response (MCR) was defined as improvement of active BILAG-2004 domains to grade C/better at 6 months. B-cell depletion was evaluated by highly-sensitive flow cytometry. Qualitative and quantitative polymorphisms for five major FcγRs were measured using a commercial multiplex ligation-dependent probe amplification. Median NK cell FcγRIIIa expression (CD3-CD56+CD16+) and NK-cell degranulation (CD107a) in the presence of rituximab-coated Daudi/Raji B-cell lines were assessed using flow cytometry.

Results

In RA, for FCGR3A, carriage of V allele (coefficient -0.25 (SE 0.11); p=0.02) and increased copies of V allele (-0.20 (0.09); p=0.02) were associated with greater 2C-DAS28 response. Irrespective of FCGR3A genotype, increased gene copies were associated with a better response. In SLE, 177/262 (67.6%) achieved BILAG response [MCR=34.4%; Partial=33.2%]. MCR was associated with increased copies of FCGR3A-158V allele, OR 1.64 (95% CI 1.12-2.41) and FCGR2C-ORF allele 1.93 (1.09-3.40). Of patients with B-cells data in the combined cohort, 236/413 (57%) achieved complete depletion post-rituximab. Only homozygosity for FCGR3A-158V and increased FCGR3A-158V copy number were associated with increased odds of complete depletion. Patients with complete depletion had higher NK cell FcγRIIIa expression at rituximab initiation than those with incomplete depletion (p=0.04) and this higher expression was associated with improved EULAR response in RA. Moreover, for FCGR3A, degranulation activity was increased in V allele carriers vs FF genotype in the combined cohort; p=0.02.

Conclusion

FcγRIIIa is the major low affinity FcγR and increased copies of the FCGR3A-158V allele, encoding the allotype with a higher affinity for IgG1, was associated with clinical and biological responses to rituximab in two autoimmune diseases. This was supported by functional data on NK cell-mediated cytotoxicity. In SLE, increased copies of the FCGR2C-ORF allele was also associated with improved response. Our findings indicate that enhancing FcγR-effector functions could improve the next generation of CD20-depleting therapies and genotyping could stratify patients for optimal treatment protocols.

References

None

Acknowledgements

This research was funded/supported by the joint funding from the Medical Research Council (MRC) and Versus Arthritis of MATURA (grant codes 36661 and MR/K015346/1). MASTERPLANS was funded by the MRC (grant code MR/M01665X/1). The Leeds Biologics Cohort was part funded by programme grants from Versus Arthritis (grant codes 18475 and 18387), the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC) and Diagnostic Evaluation Co-operative and the Ann Wilks Charitable Foundation. The BILAG-BR has received funding support from Lupus UK, and unrestricted grants from Roche and GSK.

The functional studies were in part supported through a NIHR/HEFCE Clinical Senior Lectureship and a Versus Arthritis Foundation Fellowship (grant code 19764) to AWM, the Wellcome Trust Institutional Strategic Support Fund to JIR and MYMY (204825/Z/16/Z), NIHR Doctoral Research Fellowship to MYMY (DRF-2014-07-155) and NIHR Clinician Scientist to EMV (CS-2013-13-032). . AWM, INB, JDI and PE were supported by NIHR Senior Investigator awards. Work in JDI’s laboratory is supported by the NIHR Newcastle BRC, the Research Into Inflammatory Arthritis Centre Versus Arthritis, and Rheuma Tolerance for Cure (European Union Innovative Medicines Initiative 2, grant number 777357). INB is funded by the NIHR Manchester BRC.

This article/paper/report presents independent research funded/supported by the NIHR Leeds BRC and the NIHR Guy’s and St Thomas’ BRC. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

Disclosure of Interests

Md Yuzaiful Md Yusof: None declared, James Robinson: None declared, Vinny Davies: None declared, Dawn Wild: None declared, Michael Morgan: None declared, John Taylor: None declared, Yasser El-Sherbiny: None declared, David Morris: None declared, Lu Liu: None declared, Andrew Rawstron: None declared, Maya H Buch: None declared, Darren Plant: None declared, Heather Cordell: None declared, John Isaacs: None declared, Ian N. Bruce: None declared, Paul Emery Speakers bureau: Roche, Consultant of: Roche, Grant/research support from: Roche, Anne Barton: None declared, Timothy Vyse: None declared, Jennifer Barrett: None declared, Edward Vital Consultant of: Roche, Grant/research support from: Roche, Ann Morgan Speakers bureau: Roche/Chugai, Consultant of: GSK, Roche, Chugai, AstraZeneka, Regeneron, Sanofi, Vifor, Grant/research support from: Roche, Kiniksa Pharmaceuticals

Virtual cardiac rehabilitation during the COVID-19 pandemic: a tertiary site experience

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): University of British Columbia Clinician Investigator Program

Background

The COVID-19 pandemic resulted in the abrupt suspension of centre-based cardiac rehabilitation (CR). Multidisciplinary virtual CR (VCR) with the use of digital, telephone, and video communication was implemented for continued care access. Exercise therapy was delivered through synchronous video-supervised sessions, pre-recorded sessions, and self-directed physical activity.

Purpose

To describe patient characteristics, completion rates, and safety outcomes in a real-world VCR population.

Methods

Prospective observational study of a tertiary academic CR program. VCR was implemented at pandemic onset (March 2020). Patients who were enrolled in, and either completed or dropped out, during the study period were included. Completers were defined as completing 6 months of virtual enrolment and an exit assessment. Risk was defined by the AACPVR 2020 risk categorization. Adverse cardiovascular events were defined as a patient-initiated event requiring medical assessment and stratified as exercise or non-exercise related. Continuous variables are presented as means and SD or medians and IQR. Student’s t-test was used for between group comparisons. Categorical variables are presented as n (%) and compared using the χ2 test or Fischer’s exact test. A p-value <0.05 was considered significant.

Results

Between March 13th, 2020, and August 31st, 2021, 222 [mean age 61.8 years (SD, 12.6) 77% male], were enrolled and discharged from the VCR program (Table 1). There were 160 completers and 62 non-completers (completion rate 72%). Among the non-completers 26 attended the MD intake assessment only. The remaining 36 completed a median of 85 days (IQR 25-197). This cohort included 21 (9%) high-risk and 35 (16%) moderate risk patients. Those at moderate risk were more likely to be non-completers and those at low risk were more likely to be completers (Table 1). Two exercise and 17 non-exercise adverse events were observed (median clinical surveillance 217 days [IQR 205-240]) (Table 2). Exercise related adverse events included neurally mediated syncope during a synchronous video exercise session in a low risk patient. This was responded to as per centre developed virtual safety protocols. A second syncope related to heart block occurred in a moderate risk patient during independent physical activity and required permanent pacemaker insertion. Both patients completed the program. Three non-exercise adverse cardiac events resulted in cessation of participation included one death and two heart failure hospitalizations (Table 2). One stroke and 13 emergency department visits for cardiac symptoms occurred in completers.

Conclusion

Real world VCR is feasible, including in those at moderate to high risk. Modest completion rates and a low exercise related adverse event rate were observed. Synchronous video exercise sessions with video monitoring and safety protocols may improve response to adverse exercise related events.

Radionuclide ventriculography phase analysis for risk stratification of patients undergoing cardiotoxic cancer therapy

BACKGROUND

Accurate diagnostic tools to identify patients at risk of cancer therapy-related cardiac dysfunction (CTRCD) are critical. For patients undergoing cardiotoxic cancer therapy, ejection fraction assessment using radionuclide ventriculography (RNVG) is commonly used for serial assessment of left ventricular (LV) function.

METHODS

In this retrospective study, approximate entropy (ApEn), synchrony, entropy, and standard deviation from the phase histogram (phase SD) were investigated as potential early markers of LV dysfunction to predict CTRCD. These phase parameters were calculated from the baseline RNVG phase image for 177 breast cancer patients before commencing cardiotoxic therapy.

RESULTS

Of the 177 patients, 11 had a decline in left ventricular ejection fraction (LVEF) of over 10% to an LVEF below 50% after treatment had commenced. This patient group had a significantly higher ApEn at baseline to those who maintained a normal LVEF throughout treatment. Of the parameters investigated, ApEn was superior for predicting the risk of CTRCD. Combining ApEn with the baseline LVEF further improved the discrimination between the groups.

CONCLUSIONS

The results suggest that RNVG phase analysis using approximate entropy may aid in the detection of sub-clinical LV contraction abnormalities, not detectable by baseline LVEF measurement, predicting a subsequent decline in LVEF.

Predictors of radiation dose for uterine artery embolisation are angiography system-dependent

This study sought to achieve radiation dose reductions for patients receiving uterine artery embolisation (UAE) by evaluating radiation dose measurements for the preceding generation (Allura) and upgraded (Azurion) angiography system. Previous UAE regression models in the literature could not be applied to this centre's practice due to being based on different angiography systems and radiation dose predictor variables. The aims of this study were to establish whether radiation dose is reduced with the upgraded angiography system and to develop a regression model to determine predictors of radiation dose specific to the upgraded angiography system. A comparison between Group I (Allura,n= 95) and Group II (Azurion,n= 95) demonstrated a significant reduction in kerma-area product (KAP) and Ka, r (reference air kerma) by 63% (143.2 Gy cm²vs 52.9 Gy cm²;P< 0.001,d= 0.8) and 67% (0.6 Gy vs 0.2 Gy;P< 0.001,d= 0.8), respectively. The multivariable linear regression (MLR) model identified the UAE radiation dose predictors for KAP on the upgraded angiography system as total fluoroscopy dose, Ka, r, and total uterus volume. The predictive accuracy of the MLR model was assessed using a Bland-Altman plot. The mean difference was 0.39 Gy cm²and the limits of agreement were +28.49 and -27.71 Gy cm², and thus illustrated no proportional bias. The resultant MLR model was considered system-dependent and validated the upgraded angiography system and its advance capabilities to significantly reduce radiation dose. Interventional radiologist and interventional radiographer familiarisation of the system's features and the implementation of the newly established MLR model would further facilitate dose optimisation for all centres performing UAE procedures using the upgraded angiography system.

TGF-β-mediated silencing of genomic organizer SATB1 promotes Tfh cell differentiation and formation of intra-tumoral tertiary lymphoid structures

The immune checkpoint receptor PD-1 on T follicular helper (Tfh) cells promotes Tfh:B cell interactions and appropriate positioning within tissues. Here, we examined the impact of regulation of PD-1 expression by the genomic organizer SATB1 on Tfh cell differentiation. Vaccination of CD4^CreSatb1^f/f mice enriched for antigen-specific Tfh cells, and TGF-β-mediated repression of SATB1 enhanced Tfh differentiation of human T cells. Mechanistically, high Icos expression in Satb1^-/- CD4⁺ T cells promoted Tfh cell differentiation by preventing T follicular regulatory cell skewing and resulted in increased isotype-switched B cell responses in vivo. Ovarian tumors in CD4^CreSatb1^f/f mice accumulated tumor antigen-specific, LIGHT⁺CXCL13⁺IL-21⁺ Tfh cells and tertiary lymphoid structures (TLS). TLS formation decreased tumor growth in a CD4⁺ T cell and CXCL13-dependent manner. The transfer of Tfh cells, but not naive CD4⁺ T cells, induced TLS at tumor beds and decreased tumor growth. Thus, TGF-β-mediated silencing of Satb1 licenses Tfh cell differentiation, providing insight into the genesis of TLS within tumors.

Imitation of β-lactam binding enables broad-spectrum metallo-β-lactamase inhibitors

Carbapenems are vital antibiotics, but their efficacy is increasingly compromised by metallo-β-lactamases (MBLs). Here we report the discovery and optimization of potent broad-spectrum MBL inhibitors. A high-throughput screen for NDM-1 inhibitors identified indole-2-carboxylates (InCs) as potential β-lactamase stable β-lactam mimics. Subsequent structure-activity relationship studies revealed InCs as a new class of potent MBL inhibitor, active against all MBL classes of major clinical relevance. Crystallographic studies revealed a binding mode of the InCs to MBLs that, in some regards, mimics that predicted for intact carbapenems, including with respect to maintenance of the Zn(II)-bound hydroxyl, and in other regards mimics binding observed in MBL-carbapenem product complexes. InCs restore carbapenem activity against multiple drug-resistant Gram-negative bacteria and have a low frequency of resistance. InCs also have a good in vivo safety profile, and when combined with meropenem show a strong in vivo efficacy in peritonitis and thigh mouse infection models.

Abstract P257: Preclinical data identifies bezuclastinib as a differentiated KIT inhibitor with unique selectivity to KIT D816V and minimal evidence of brain penetration

KIT is a well characterized oncogenic driver of gastro-intestinal stromal tumors (GIST) and systemic mastocytosis (SM), and targeted therapeutics have offered valuable treatment options for these patients. Durable responses in imatinib-resistant GIST are rarely achieved due to secondary mutations that occur in exons 13/14 and 17/18. Exon 13/14 mutations can be addressed with sunitinib treatment, but identifying inhibitors that additionally target exon 17/18 mutations without incurring off-target toxicities related to broad-spectrum kinase inhibition has been challenging. Similarly, agents targeting KIT D816V mutations have shown activity in the treatment of advanced SM, but toxicities such as cognitive effects and intracranial hemorrhage may limit dosing and availability of these therapies. Bezuclastinib (CGT9486) was designed to inhibit exon 17/18 KIT mutations (including KIT D816V) with selectivity versus other closely-related kinases with known liabilities, such as PDGFRα, PDGFRβ, KIT wt, VEGFR2 (KDR), and CSF1R (FMS). Herein, we are presenting results from cell-based kinase profiling assays, which demonstrate that bezuclastinib has a significant and unique selectivity to KIT D816V vs. these aforementioned kinases when tested head-to-head against other clinically relevant compounds in GIST or SM. Additionally, a similar selectivity profile was observed for a broader panel of kinases, ion channels, transporters, and enzymes, which will be presented here. Importantly, we also show that bezuclastinib has minimal brain penetration. In a tissue distribution study performed in rats, bezuclastinib shows a brain:plasma ratio &lt;0.1 following 3 day administration at 25 mg/kg, a dose that closely correlates with clinical exposure. This was supported functionally by assessing neurobehavioral effects of bezuclastinib at dose levels up to 100 mg/kg which showed no CNS related effects. Minimal brain penetration is a preferred feature of an anti-Kit molecule due to CNS-related adverse events observed in these indications. This attractive selectivity and nonclinical safety profile, combined with early clinical data (1) in advanced solid tumors, supports the potential for a best-in-class KIT inhibitor. Bezuclastinib is currently under clinical investigation in advanced SM with additional clinical studies planned in non-advanced SM and imatinib-resistant GIST. 1. Jonathan Trent, William D. Tap, Rashmi Chugh, Gabriel Tinoco, Athanasios Tsiatis, Paul Severson, Kerry Inokuchi, Chao Zhang, Glenn Michelson, Andrew J. Wagner. The Potent and Selective KIT Inhibitor PLX9486 Dosed in Combination With Sunitinib Demonstrates Promising Progression Free Survival (PFS) in Patients With Advanced Gastrointestinal Stromal Tumor (GIST): Final Results of a Phase 1/2 Study. Abstract Presented at the Connective Tissue Oncology Society Virtual Meeting; November 20, 2020.

Citation Format: Anna Guarnieri, Mark Chicarelli, LouAnn Cable, Francis Sullivan, Howard Ball, Shannon Winski, John Robinson. Preclinical data identifies bezuclastinib as a differentiated KIT inhibitor with unique selectivity to KIT D816V and minimal evidence of brain penetration [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P257.

3D Printed Cobalt-Chromium-Molybdenum Porous Superalloy with Superior Antiviral Activity

COVID-19 pandemic and associated supply-chain disruptions emphasise the requirement for antimicrobial materials for on-demand manufacturing. Besides aerosol transmission, SARS-CoV-2 is also propagated through contact with virus-contaminated surfaces. As such, the development of effective biofunctional materials that can inactivate SARS-CoV-2 is critical for pandemic preparedness. Such materials will enable the rational development of antiviral devices with prolonged serviceability, reducing the environmental burden of disposable alternatives. This research reveals the novel use of Laser Powder Bed Fusion (LPBF) to 3D print porous Cobalt-Chromium-Molybdenum (Co-Cr-Mo) superalloy with potent antiviral activity (100% viral inactivation in 30 min). The porous material was rationally conceived using a multi-objective surrogate model featuring track thickness (tt) and pore diameter (ϕd) as responses. The regression analysis found the most significant parameters for Co-Cr-Mo track formation to be the interaction effects of scanning rate (Vs) and laser power (Pl) in the order PlVs>Vs>Pl. Contrastively, the pore diameter was found to be primarily driven by the hatch spacing (Sh). The study is the first to demonstrate the superior antiviral properties of 3D printed Co-Cr-Mo superalloy against an enveloped virus used as biosafe viral model of SARS-CoV-2. The material significantly outperforms the viral inactivation time of other broadly used antiviral metals such as copper and silver, as the material's viral inactivation time was from 5 h to 30 min. As such, the study goes beyond the current state-of-the-art in antiviral alloys to provide extra protection to combat the SARS-CoV-2 viral spread. The evolving nature of the COVID-19 pandemic brings new and unpredictable challenges where on-demand 3D printing of antiviral materials can achieve rapid solutions while reducing the environmental impact of disposable devices.

P039 INTERCOSTAL HERNIA FOLLOWING DIEP RECONSTRUCTION: A CASE PRESENTATION

Aim

Intercostal lung herniation is a rare clinical condition defined as the protrusion of lung parenchyma beyond the anatomic boundaries of the thoracic wall. Acquired lung hernias are typically occur secondary to trauma or are associated with severe pulmonary disease. We present a case of lung herniation following DIEP breast reconstruction which is the first reported case to date.

Material and Methods

40-year-old woman with a history of bilateral mastectomy for breast cancer and subsequent delayed, bilateral DIEP breast reconstruction. She returned to the emergency department four days after her reconstruction with chest pain, shortness of breath and swelling of her chest. CT angiography of her chest demonstrated a focal protrusion of her right lung into her anterior chest wall (Figure 1). Thoracic surgery was consulted for repair which was achieved with a patch technique using Allomax dermal matrix.

Results

We describe the first reported intercostal lung hernia following DIEP breast reconstruction reported in scientific literature. Our patient had no history of trauma, thoracic surgery or pulmonary disease which are considered the greatest risk factors for acquired intercostal lung herniation. Much like abdominal wall hernias, protrusion of tissue through a small defect places tissue at risk for ischemia. Early recognition is thus essential to avoid tissue loss.

Conclusions

Intercostal lung hernia is an uncommon clinical entity that has not previously been described as a complication of DIEP breast reconstruction. Its development is associated with significant morbidity including flap loss in this case. Early recognition of this rare complication is essential to avoid more severe sequelae of tissue ischemia.

UTERINE ARTERY EMBOLISATION: CONTINUOUS QUALITY IMPROVEMENT REDUCES RADIATION DOSE WHILE MAINTAINING IMAGE QUALITY

The purpose of this study was to introduce a continuous quality improvement (CQI) program for radiation dose optimisation during uterine artery embolisation (UAE) and assess its impact on dose reduction and image quality. The CQI program investigated the effects of optimising radiation dose parameters on the kerma-area product (KAP) and image quality when comparing a 'CQI intervention' group (n = 50) and 'Control' group (n = 50). Visual grading characteristics (VGC) analysis was used to assess image quality, using the 'Control' group as a reference. A significant reduction in KAP by 17% (P = 0.041, d = 0.2) and reference air kerma (Ka, r) by 20% (P = 0.027, d = 0.2) was shown between the two groups. The VGC analysis resulted in an area under the VGC curve (AUCVGC) of 0.54, indicating no significant difference in image quality between the two groups (P = 0.670). The implementation of the CQI program and optimisation of radiation dose parameters improved the UAE radiation dose practices at our centre. The dose reduction demonstrated no detrimental effects on image quality.

Deep sr-DDL: Deep structurally regularized dynamic dictionary learning to integrate multimodal and dynamic functional connectomics data for multidimensional clinical characterizations

We propose a novel integrated framework that jointly models complementary information from resting-state functional MRI (rs-fMRI) connectivity and diffusion tensor imaging (DTI) tractography to extract biomarkers of brain connectivity predictive of behavior. Our framework couples a generative model of the connectomics data with a deep network that predicts behavioral scores. The generative component is a structurally-regularized Dynamic Dictionary Learning (sr-DDL) model that decomposes the dynamic rs-fMRI correlation matrices into a collection of shared basis networks and time varying subject-specific loadings. We use the DTI tractography to regularize this matrix factorization and learn anatomically informed functional connectivity profiles. The deep component of our framework is an LSTM-ANN block, which uses the temporal evolution of the subject-specific sr-DDL loadings to predict multidimensional clinical characterizations. Our joint optimization strategy collectively estimates the basis networks, the subject-specific time-varying loadings, and the neural network weights. We validate our framework on a dataset of neurotypical individuals from the Human Connectome Project (HCP) database to map to cognition and on a separate multi-score prediction task on individuals diagnosed with Autism Spectrum Disorder (ASD) in a five-fold cross validation setting. Our hybrid model outperforms several state-of-the-art approaches at clinical outcome prediction and learns interpretable multimodal neural signatures of brain organization.

Effect of body mass index on cardiac injury/cardiovascular outcomes in coronavirus disease 2019: a systematic review and meta-analysis

 

Coronavirus disease 2019 has affected millions of people worldwide. Its clinical spectrum ranges from completely asymptomatic to significant respiratory and non-respiratory symptoms leading to critical illness, including death. We aimed to study the effects of body mass index (BMI) on cardiovascular and other critical illness outcomes in these patients in the USA. We conducted a systematic search of three databases for the period of November 2019 to August 2020 and selected 37 studies for analysis. One study showed a non-significant difference in cardiac injury among BMI groups, but there is a paucity of data on cardiovascular outcomes among different BMI groups; hence, meta-analysis was not done for cardiovascular outcomes. Both high BMI and cardiac injury are independent predictors of poor outcomes in these patients. Pooled analysis showed obesity as a significant risk factor for intensive care unit admission (OR=1.547, CI=1.208–1.981, P=0.001) and intubation /mechanical ventilation (OR=1.744, CI=1.363–2.231 P=0.000). Therefore, BMI should be considered an important part of risk stratification, and vaccination should be prioritized for obese patients when it becomes widely available.

Funding Acknowledgement

Type of funding sources: None. Risk of intubation

A Likelihood-Ratio Test for Lumpability of Phylogenetic Data: Is the Markovian Property of an Evolutionary Process retained in Recoded DNA?

In molecular phylogenetics, it is typically assumed that the evolutionary process for DNA can be approximated by independent and identically distributed Markovian processes at the variable sites and that these processes diverge over the edges of a rooted bifurcating tree. Sometimes the nucleotides are transformed from a 4-state alphabet to a 3- or 2-state alphabet by a procedure that is called recoding, lumping, or grouping of states. Here, we introduce a likelihood-ratio test for lumpability for DNA that has diverged under different Markovian conditions, which assesses the assumption that the Markovian property of the evolutionary process over each edge is retained after recoding of the nucleotides. The test is derived and validated numerically on simulated data. To demonstrate the insights that can be gained by using the test, we assessed two published data sets, one of mitochondrial DNA from a phylogenetic study of the ratites (Syst. Biol. 59:90-107 [2010]) and the other of nuclear DNA from a phylogenetic study of yeast (Mol. Biol. Evol. 21:1455-1458 [2004]). Our analysis of these data sets revealed that recoding of the DNA eliminated some of the compositional heterogeneity detected over the sequences. However, the Markovian property of the original evolutionary process was not retained by the recoding, leading to some significant distortions of edge lengths in reconstructed trees.

The role of quality improvement in radiography

This editorial discusses the importance of quality improvement and quality assurance in the provision of medical imaging services, by exploring two studies which aim to improve the quality of practice in emergency departments (ED). The quality of work by ED radiographers are continually planned, measured, assessed, and improved to enhance patient care outcomes - from the accurate diagnosis of patients, maintaining the consistency of diagnostic images, and to minimising radiation exposure to patients.

An online Sexual Health and Rehabilitation eClinic (TrueNTH SHAReClinic) for prostate cancer patients: a feasibility study

Purpose

The primary objective was to determine the feasibility of implementing the TrueNTH SHAReClinic as a pan-Canadian sexual health and rehabilitation intervention for patients treated for localized prostate cancer.

Methods

The feasibility study was designed to evaluate the accessibility and acceptability of the intervention. Participants from five institutions across Canada were enrolled to attend one pre-treatment and five follow-up online clinic visits over 1 year following their prostate cancer (PC) treatment.

Results

Sixty-five patients were enrolled in the intervention. Website analytics revealed that 71% completed the intervention in its entirety, including the educational modules, with an additional 10% completing more than half of the intervention. Five thousand eighty-three views of the educational modules were made along with 654 views of the health library items. Over 1500 messages were exchanged between participants and their sexual health coaches. At 12 months, the intervention received an overall average participant rating of 4.1 out of 5 on a single item satisfaction measure.

Conclusion

Results support the TrueNTH SHAReClinic as highly acceptable to participants as defined by intervention adherence and engagement. The TrueNTH SHAReClinic demonstrated promise for being a feasible and potentially resource-efficient approach to effectively improving the sexual well-being of patients after PC treatment.

Identifying predictors of patient radiation dose during uterine artery embolisation

INTRODUCTION

Uterine artery embolisation (UAE) is regarded as a safe and effective treatment for symptomatic uterine fibroids and/or adenomyosis. Dose reduction during UAE is critical for this reproductive-age patient population to minimise the risks of radiation-induced effects. The aim of this study was to identify the predictors of radiation dose which can be controlled and optimised for patients during UAE.

METHODS

A total of 150 patients between June 2018 and August 2019 were included in this study. Demographic and clinical information such as age, body mass index (BMI), total number of fibroids, total fibroid volume, total uterus volume and dosimetric measurements on Dose Area Product (DAP), Air Kerma (AK) and fluoroscopy time were recorded. Total digital subtraction angiography (DSA), total conventional roadmap (CRM), total last-image hold (LIH) and total fluoroscopy were calculated from the dose report. Multiple linear regression analysis was used to identify the independent predictor variables of total dose (DAP) using a regression model.

RESULTS

Total DSA, total CRM and total LIH were identified as the determinants of dose for UAE (P < 0.05) and together accounted for 95.2% of the variance.

CONCLUSIONS

This study identified the key imaging predictors of dose for UAE. Total DSA, total CRM and total LIH were shown to have a greater impact on the outcome DAP compared to other demographic or dosimetric measurements. Optimisation of these predictors during future UAE procedures can facilitate radiation dose reduction to the pelvis and reproductive organs.