Acoustic field visualisation using local absorption of ultrasound and thermochromic liquid crystals

Acoustic field and vibration visualisation is important in a wide range of applications. Laser vibrometry is often used for such visualisation, however, the equipment has a high cost and requires significant user expertise, and the method can be slow, as it requires scanning point by point. Here we suggest a different approach to visualisation of acoustic fields in the kHz - MHz range, using paint-on or removable film sensors, which produce a direct visual map of ultrasound displacement. The sensors are based on a film containing thermochromic liquid crystals (TLC), along with a backing/underlay layer which improves absorption of ultrasound. The absorption generates heat, which can be seen by a change in colour of the TLC film. A removable sensor is used to visualise the resonant modes of an air-coupled flexural transducer operated from 410 kHz to 7.23 MHz, and to visualise 40 kHz standing waves in a Perspex plate. The thermal basis of the visualisation is confirmed using thermal imaging. The speed and cost of visualisation makes the new sensor attractive for use in condition monitoring, for fast assessment of transducer quality, or for analysis of acoustic field distribution in power ultrasonic systems.

Nucleosome conformation dictates the histone code

Histone post-translational modifications (PTMs) play a critical role in chromatin regulation. It has been proposed that these PTMs form localized 'codes' that are read by specialized regions (reader domains) in chromatin-associated proteins (CAPs) to regulate downstream function. Substantial effort has been made to define [CAP: histone PTM] specificities, and thus decipher the histone code and guide epigenetic therapies. However, this has largely been done using the reductive approach of isolated reader domains and histone peptides, which cannot account for any higher-order factors. Here, we show that the [BPTF PHD finger and bromodomain: histone PTM] interaction is dependent on nucleosome context. The tandem reader selectively associates with nucleosomal H3K4me3 and H3K14ac or H3K18ac, a combinatorial engagement that despite being in cis is not predicted by peptides. This in vitro specificity of the BPTF tandem reader for PTM-defined nucleosomes is recapitulated in a cellular context. We propose that regulatable histone tail accessibility and its impact on the binding potential of reader domains necessitates we refine the 'histone code' concept and interrogate it at the nucleosome level.

Multivalent binding of the tardigrade Dsup protein to chromatin promotes yeast survival and longevity upon exposure to oxidative damage

Tardigrades are remarkable in their ability to survive extreme environments. The damage suppressor (Dsup) protein is thought responsible for their extreme resistance to reactive oxygen species (ROS) generated by irradiation. Here we show that expression of Ramazzottius varieornatus Dsup in Saccharomyces cerevisiae reduces oxidative DNA damage and extends the lifespan of budding yeast exposed to chronic oxidative genotoxicity. This protection from ROS requires either the Dsup HMGN-like domain or sequences C-terminal to same. Dsup associates with no apparent bias across the yeast genome, using multiple modes of nucleosome binding; the HMGN-like region interacts with both the H2A/H2B acidic patch and H3/H4 histone tails, while the C-terminal region binds DNA. These findings give precedent for engineering an organism by physically shielding its genome to promote survival and longevity in the face of oxidative damage.

From CoNFLict to Confidence: Solving a Diagnostic Dilemma Using Neurofilament Light – A Case Report

Distinguishing neurodegenerative from primary psychiatric conditions is often challenging for clinicians, particularly when assessing older people presenting with neuropsychiatric symptoms. Measurement of fluid biomarkers of neurodegeneration is an emerging approach offering improved diagnostic accuracy. This report explores the use of emerging fluid biomarkers to address diagnostic challenges, framed around a case where the diagnosis of delirium with dementia was revised based on biomarker analysis, enabling treatment of a primary mood disorder with disabling psychiatric symptoms.

Protocol of a Phase II Randomized, Multi-Center, Double-Blind, Placebo-Controlled Trial of S-Adenosyl Methionine in Participants with Mild Cognitive Impairment or Dementia Due to Alzheimer's Disease

BACKGROUND

S-adenosyl methionine (SAMe) is a pivotal metabolite in multiple pathways required for neuronal homeostasis, several of which are compromised in Alzheimer's disease (AD). Correction of the SAMe deficiency that is characteristic of the AD brain may attenuate or prevent pathological processes driving AD-associated neurodegeneration including aberrant tau hyperphosphorylation and DNA hypomethylation.

OBJECTIVES

The primary aim is to test the hypothesis that daily treatment with 400 mg oral SAMe for 180 days will lead to a greater reduction from baseline in plasma levels of p-tau181 compared to placebo in patients with mild cognitive impairment or dementia due to AD.

DESIGN, SETTING, PARTICIPANTS

This is a phase II, randomized, multi-center, double-blind, placebo-controlled trial among 60 participants with mild cognitive impairment or dementia due to AD. Participants will be randomized in a 1:1 ratio to receive either SAMe or matching placebo, to be taken as an adjunct to their AD standard of care.

MEASUREMENTS AND RESULTS

The primary outcome is change in plasma p-tau181 concentration between baseline and following 180 days of treatment, which will be compared between the active and placebo group. Secondary outcomes are the safety of SAMe administration (incidence of serious adverse events), change from baseline in cognitive performance (as measured by the Repeatable Battery for the Assessment of Neuropsychological Status), and epigenetic changes in DNA methylation.

CONCLUSION

Demonstration of effective and safe lowering of plasma p-tau181 with SAMe in this phase II trial would pave the way for an exciting field of translational research and a larger phase III trial.

TNF-α‒Mediated Keratinocyte Expression and Release of Matrix Metalloproteinase 9: Putative Mechanism of Pathogenesis in Stevens‒Johnson Syndrome/Toxic Epidermal Necrolysis

Stevens‒Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are severe cutaneous adverse drug reactions characterized by widespread keratinocyte cell death and epidermal detachment. At present, there is little understanding of how the detachment occurs or how it is abrogated by the TNF-α inhibitor etanercept, an effective SJS/TEN treatment. RNA sequencing was used to identify upregulated transcripts in formalin-fixed paraffin-embedded SJS/TEN skin biopsies. Epidermal matrix metalloproteinase 9 (MMP9) expression was assessed by immunohistochemistry in skin biopsies and cultured human skin explants exposed to serum from patients with cutaneous adverse drug reactions. TNF-α‒induced MMP9 expression and activity and its abrogation by etanercept were determined using the HaCaT immortalized keratinocyte cell line. Epidermal MMP9 expression was significantly higher in SJS/TEN skin (70.6%) than in healthy control skin (0%) (P = 0.0098) and nonbullous skin reactions (10.7%) (P = 0.0002). SJS/TEN serum induced significant MMP9 expression and collagenase activity in healthy skin explants, which was reduced by etanercept. Etanercept was also able to negate the TNF-α‒induced MMP9 expression in the HaCaT cell line. Data suggest that elevated epidermal MMP9 expression and collagenase activity are a putative pathogenic mechanism in SJS/TEN, which is limited by etanercept. Modulation of MMP9 expression and activity represents, to our knowledge, a previously unreported therapeutic target for the treatment of SJS/TEN.

1199. Implementation of a Nasal Antiseptic Decolonization Program Reduces the Occurrence of Healthcare-Associated Infections in the Adult Intensive Care Unit Setting

Background

Universal decolonization programs effectively reduce methicillin-resistant Staphylococcus aureus (MRSA) infections, bloodstream infections, and healthcare costs. However, universal decolonization programs that utilize mupirocin may promote antimicrobial resistance. Non-antibiotic interventions, such as nasal antiseptic decolonization, can contribute to the prevention of healthcare-associated infections (HAIs). A large hospital system sought to evaluate the impact of a universal nasal antiseptic program on HAIs in the adult intensive care unit (ICU) setting.

Methods

A nasal antisepsis decolonization quality improvement project (QIP) was implemented to reduce ICU HAIs by applying a 62% nasal antiseptic swab with emollients bilaterally to the nares every 12 hours for all adult ICU patients. The program was piloted across nine ICUs at three large hospitals from November 2021 to January 2022 and captured data from 12,404 patient days and 4,058 treatment days. Central line-associated blood stream infection (CLABSI), catheter-associated urinary tract infection (CAUTI), and MRSA bacteremia rates were compared a) between treated and non-treated patients during the QIP period and b) to rates during a three-month period prior to the QIP.

Results

The results of the pilot program indicated that patients who received treatment with the 62% nasal swab developed fewer HAIs than patients who did not receive the treatment. Two HAIs occurred in the treatment group (two CAUTIs) compared to 14 HAIs in the non-treatment group (three CAUTIs, nine CLABSIs, and two MRSA bacteremia). Figures 1 and 2 below demonstrate HAI rates in the non-treatment and the treatment groups. Figure 1Figure 2

Conclusion

Based on pilot results, the system approved implementation of a universal nasal antisepsis program using the 62% alcohol based nasal swab with emollients for expansion to all adult critical care units. Considerations for the future implementation of the program include broadening patient inclusion and performing ongoing HAI surveillance of treated and untreated patient groups.

Disclosures

All Authors: No reported disclosures.

Abstract B015: Versatile biochemical and genomic platforms for drug discovery in chromatin remodeling research

Chromatin remodeling, driven by ATP-dependent remodeling enzymes, plays key roles in regulating gene expression, genome replication and repair. Aberrant nucleosome organization can severely disrupt these important processes, driving various cancers and developmental disorders. Remarkably, nearly 20% of all human cancers contain mutations in subunits from the SWI/SNF family of chromatin remodeling complexes, making them attractive therapeutic targets and interests of basic research. However, studies on the remodeling enzymes (and their multi-subunit complexes) in vitro are challenging partially due to the requirement for nucleosome-based substrates. We have created the EpiDyne® nucleosome remodeling substrate portfolio for use in biochemical assays to examine nucleosome immobilizing activities of chromatin remodelers. Here we present the development of multiple remodeling assays on the EpiDyne® platform (EpiDyne®-FRET, EpiDyne®-PicoGreenTM and EpiDyne®-TR-FRET). These nonradioactive plate-based assays are easy to use, ready for high-throughput inhibitor screening, and can be customized for various remodeling enzymes that exhibit distinct preferences in nucleosome compositions. Furthermore, genome-wide mapping of chromatin remodelers is fundamental for understanding their functions in diseases and responses to inhibitors in cells, but is often obscured by unreliable ChIP-seq approaches. To this end, we have optimized the CUTANA™ CUT&RUN approach to efficiently capture localizations of all major classes of chromatin remodelers with high signal to background. As a complementary research tool to the EpiDyne® platform, CUT&RUN facilitates the epigenomic research on chromatin remodelers for drug discoveries.

Citation Format: Natalia L. Husby, Lu Sun, Hannah Willis, Matthew R. Marunde, Matt J. Meiners, Zachary Gillespie, Rachel Watson, Saarang Gopinath, Jonathan M. Burg, Marcus A. Cheek, Katherine Novitzky, Bryan J. Venters, Zu-Wen Sun, Michael-Christopher Keogh. Versatile biochemical and genomic platforms for drug discovery in chromatin remodeling research. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr B015.

POS0478 TOPICAL CALCIUM CHELATORS FOR TARGETING CUTANEOUS CALCIFICATION: PRECLINICAL EVIDENCE OF EFFICACY

Background

Cutis calcinosis, defined as sub-epidermal deposition of calcium salts, is a painful, disabling, disfiguring, problem in 20-40% of patients with systemic sclerosis. Its pathogenesis remains poorly understood and currently there is no effective disease-modifying pharmacotherapy. One potential strategy is topical application of calcium chelating agents, able to penetrate the epidermal barrier and dissolve subcutaneous calcinotic deposits in situ. To date, the only compound reported for this application has been sodium thiosulfate (STS), with often-contradictory results.

Objectives

To test the hypothesis, in pre-clinical studies, that polycarboxylic acids can induce calcium dissolution without skin toxicity, with the long-term aim of developing an effective topical treatment for cutis calcinosis.

Methods

We compared the metal ion-chelating agents citric acid (CA) and ethylenediaminetetraacetic acid (EDTA) - polycarboxylic acids with well-characterised chelation profiles – to STS for their ability to chelate calcium, without inducing cytotoxicity or inflammation (pro-inflammatory cytokine expression and release), using in vitro 2D (keratinocyte [HaCaT]; fibroblast ([HCA2]) and recombinant human epidermal (RHE) models. The resultant data was subsequently used to predict therapeutic concentrations for assessment in a validated skin irritation model (SkinEthicTM; Episkin SA) and to assay maximal percutaneous absorption. At relative dermal concentrations, the dissolution performance of each chelator was further assessed using two different models of calcinosis: 1) pharmaceutical dissolution of a hydroxyapatite (HAp) tablet (1) and; 2) dissolution of a calcified extracellular matrix laid down by mineralising SaOS2 in vitro monolayer culture (2).

Results

Incubation with CA, EDTA and STS induced cytotoxicity in both in vitro cell lines studied at concentrations of >10 mM; only EDTA (10 mM) resulted in inflammatory cytokine release (IL8) from cells at these higher concentrations (cf positive control, Lipopolysaccharide 10 mg/mL). When applied topically to RHE models as near-saturated solutions, none of the chelators were categorised as skin irritants. Due to differences in their relative aqueous solubility, higher concentrations of CA (1600 mM) and STS (1200 mM) could be delivered through the RHE model than EDTA (200 mM). Using a simple linear regression model, the rate of compound absorption was: CA, 0.43 ± 0.05; STS, 0.26 ± 0.03 and; EDTA, 0.05 ± 0.01 g/L/hr. At each time-point, the cumulative concentration of compound in the receptor media was CA > STS > EDTA. Incubation with chelators had no effect on the integrity of the RHE by standard histology. Based on the rate of percutaneous absorption, the dissolution performance of each chelator was tested at relative dermal concentrations for phosphate dissolution (nmoles) of HAp (CA, 9.61 ±0.97; EDTA, 5.38 ± 0.28; 3.78 ± 0.58) and in the calcified in vitro model (Figure 1; CA, 3285 ± 105, STS, 947 ± 95, EDTA, 1174 ± 89), showing the superiority of CA in both model systems.

Figure 1.

Dissolution of a calcified extracellular matrix by citric acid

Conclusion

Overall, this study highlights the promise of polycarboxylic acids, particularly CA, to target subcutaneous calcification, which are neither toxic nor inflammatory to the skin. Specifically, we have identified CA as a potentially more efficacious alternative to STS for the topical treatment of cutis calcinosis.

References

[1]Fei F, Gallas A, Chang YC, Rao Y, Hunter AC, Winpenny REP, Herrick AL, Lockyer NP, Blanford CF. 2017. Quartz crystal microbalance assay of clinical calcinosis samples and their synthetic models differentiates the efficacy of chelation-based treatments. ACS Appl Mater Interfaces, 9(33):27544-27552

[2]Wang QG, Wimpenny I, Dey RE, Zhong X, Youle PJ, Downes S, Watts DC, Budd PM, Hoyland JA, Gough JE. 2018. The unique calcium chelation property of poly(vinyl phosphonic acid-co-acrylic acid) and effects on osteogenesis in vitro. J Biomed Mater Res Part A 2018:106A:168–179

Disclosure of Interests

Kyle Burgess: None declared, Richard Winpenny: None declared, Alberto Saiani: None declared, Ariane Herrick Speakers bureau: Janssen, Consultant of: Arena, Boehringer-Ingelheim, Camurus, CSL-Behring, Gesynta, Grant/research support from: Gesynta, Rachel Watson Consultant of: NAOS, AbbVie, Grant/research support from: Walgreens Alliance Boots.

Food for all: designing sustainable and secure future seafood systems

Food from the sea can make a larger contribution to healthy and sustainable diets, and to addressing hunger and malnutrition, through improvements in production, distribution and equitable access to wild harvest and mariculture resources and products. The supply and consumption of seafood is influenced by a range of 'drivers' including ecosystem change and ocean regulation, the influence of corporations and evolving consumer demand, as well as the growing focus on the importance of seafood for meeting nutritional needs. These drivers need to be examined in a holistic way to develop an informed understanding of the needs, potential impacts and solutions that align seafood production and consumption with relevant 2030 Sustainable Development Goals (SDGs). This paper uses an evidence-based narrative approach to examine how the anticipated global trends for seafood might be experienced by people in different social, geographical and economic situations over the next ten years. Key drivers influencing seafood within the global food system are identified and used to construct a future scenario based on our current trajectory (Business-as-usual 2030). Descriptive pathways and actions are then presented for a more sustainable future scenario that strives towards achieving the SDGs as far as technically possible (More sustainable 2030). Prioritising actions that not only sustainably produce more seafood, but consider aspects of access and utilisation, particularly for people affected by food insecurity and malnutrition, is an essential part of designing sustainable and secure future seafood systems.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11160-021-09663-x.

Food for all: designing sustainable and secure future seafood systems

Food from the sea can make a larger contribution to healthy and sustainable diets, and to addressing hunger and malnutrition, through improvements in production, distribution and equitable access to wild harvest and mariculture resources and products. The supply and consumption of seafood is influenced by a range of 'drivers' including ecosystem change and ocean regulation, the influence of corporations and evolving consumer demand, as well as the growing focus on the importance of seafood for meeting nutritional needs. These drivers need to be examined in a holistic way to develop an informed understanding of the needs, potential impacts and solutions that align seafood production and consumption with relevant 2030 Sustainable Development Goals (SDGs). This paper uses an evidence-based narrative approach to examine how the anticipated global trends for seafood might be experienced by people in different social, geographical and economic situations over the next ten years. Key drivers influencing seafood within the global food system are identified and used to construct a future scenario based on our current trajectory (Business-as-usual 2030). Descriptive pathways and actions are then presented for a more sustainable future scenario that strives towards achieving the SDGs as far as technically possible (More sustainable 2030). Prioritising actions that not only sustainably produce more seafood, but consider aspects of access and utilisation, particularly for people affected by food insecurity and malnutrition, is an essential part of designing sustainable and secure future seafood systems.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11160-021-09663-x.

A trivalent nucleosome interaction by PHIP/BRWD2 is disrupted in neurodevelopmental disorders and cancer

Mutations in the PHIP/BRWD2 chromatin regulator cause the human neurodevelopmental disorder Chung-Jansen syndrome, while alterations in PHIP expression are linked to cancer. Precisely how PHIP functions in these contexts is not fully understood. Here we demonstrate that PHIP is a chromatin-associated CRL4 ubiquitin ligase substrate receptor and is required for CRL4 recruitment to chromatin. PHIP binds to chromatin through a trivalent reader domain consisting of a H3K4-methyl binding Tudor domain and two bromodomains (BD1 and BD2). Using semisynthetic nucleosomes with defined histone post-translational modifications, we characterize PHIPs BD1 and BD2 as respective readers of H3K14ac and H4K12ac, and identify human disease-associated mutations in each domain and the intervening linker region that likely disrupt chromatin binding. These findings provide new insight into the biological function of this enigmatic chromatin protein and set the stage for the identification of both upstream chromatin modifiers and downstream targets of PHIP in human disease.

Internal jugular vein ultrasound in patients with chronic congestive heart failure

Background

Bedside assessment of intravascular volume in patients with chronic congestive heart failure (CHF) is often difficult. Under- and over-diuresis are common causes of morbidity and readmissions in these patients.

Purpose

We hypothesized that ultrasound assessment of the internal jugular vein would be easier and more reproducible than clinically assessing jugular venous pressure (JVP). Our goal was to create a bedside test that would be simpler to learn than inferior vena cava (IVC) assessment and easier to perform in obese patients.

Methods

Adults with HF (n=53, 52% men, mean age 65 years, mean BMI 29.6 kg/m2, mean LVEF 44%) scheduled for right heart catheterization (RHC) had an ultrasound of their right internal jugular (RIJ) vein performed immediately prior. Cross-sectional area of RIJ was measured during normal breathing with patients at 90 and 45 degrees recumbency and was indexed by height (RIJI). JVP was also assessed clinically. Results were compared to right atrial pressure (RAP) measured by RHC. Operators were blinded to RHC results and vice versa.

Results

JVP was correctly assessed clinically in only 43%. RIJI at 90 and 45 degrees were significantly larger in patients with elevated RAP compared to euvolemic patients (Table). At 90 degrees, RIJI of >15 predicted a RAP of >10 mmHg with 68% sensitivity and 72% specificity. At 45 degrees, RIJI of >10 predicted a RAP of >10 mmHg with 94% sensitivity and a negative predictive value of 80% (Table). Simply being able to see the RIJ at 90 degrees (n=34) had an 82.4% positive predictive value for elevated RAP. IVC data could not be obtained on 23% of patients due to body habitus or inability to lay flat.

Conclusion

Ultrasonographic RIJI is more accurate than clinical assessment in patients with CHF and can be accurately performed even in obese patients. It requires only a basic linear ultrasound probe and was easily performed by clinicians at various stages of training with reproducible results. With the increased availability of bedside ultrasound in clinical practice, it is a feasible method of evaluating chronic CHF patients.

Funding Acknowledgement

Type of funding sources: None.

P14.29 The treatment of melanoma brain metastases with stereotactic radiosurgery concurrently with immune checkpoint inhibition is associated with improved extracranial disease control and overall survival compared to the overall metastatic melanoma cohort - a synergistic effect reaching beyond local control?

BACKGROUND

Melanoma brain metastases (MBM) are an increasingly common referral to the neuro-oncology MDT in the context of lengthening survivorship of metastatic melanoma (MM) patients in the immunotherapy era. Stereotactic radiosurgery (SRS) and immune checkpoint inhibition (ICI) are both effective in the management of MBM and, when combined, 12-month local control rates of >85% and overall survival (OS) >80% have been reported.[4,5] Recent local analysis of patients treated at our tertiary SRS referral centre has revealed even greater outcomes in this patient cohort. This study aimed to compare the outcomes of patients with MBM treated with concurrent SRS and ICI compared to the overall metastatic melanoma cohort, to elucidate whether the addition of SRS to ICI may improve disease control outside of the brain as well as within.

MATERIAL AND METHODS

A retrospective analysis of our local SRS database and an ARIA ePrescribing database search was performed to identify a cohort of patients treated with concurrent SRS and ICI for MBM, as well as a control cohort of MM patients who received ICI alone, over a 4 year period until February 2020. The primary endpoints were the extracranial progression free survival (PFS) and overall survival (OS) at 12 months. Secondary endpoints were the median PFS (mPFS) and OS (mOS). Kaplan-Meier curves and survival statistics were generated using SPSS v26.

RESULTS

A total of 34 MBM from 19 patients were identified in the SRS+ICI group and there were 200 patients in the control group. The minimum follow up was 12 months. The median patient age, duration of ICI and use of combination ICI favoured the SRS+ICI group. The number of sites of extracranial disease pre-ICI and overall anti-PD-1 usage was well matched. In the SRS+ICI group, there were no cases of extracranial progression and no deaths within 12 months. In the control group, the 12-month PFS and OS rates were 50.5% and 77.5% respectively. In terms of mPFS, this was not reached (estimated 37.6 months) in the SRS+ICI group, versus 13.4 months in the control group (log rank test, p=0.001). In terms of mOS, this was not reached in the SRS+ICI group, versus 55.8 months in the control group (log rank test, p=0.016).

CONCLUSION

We demonstrate improved extracranial disease control and survivorship amongst metastatic melanoma patients who develop brain metastases and are treated with concurrent SRS and ICI compared to those who do not. The outcomes of our control cohort are comparable to the 4-year follow up of the CheckMate 067 trial (n=945),[6] which strengthens the validity of the statistical comparisons made in this study. The improved extracranial disease control seen when SRS and ICI are combined in the treatment of MBM questions whether an abscopal effect may be at play, and therefore further accents the utility of SRS in MBM beyond that of local control alone. This could influence management in cases of borderline decisions for SRS.

P14.85 Impact of the neuro-radiologist and neuro-surgeon in contouring with the neuro-oncologist on local relapse rates for brain metastases treated with stereotactic radiosurgery

BACKGROUND

The audit evaluates the value of MDT, including neuro-radiologist and neuro-surgeon, review of contouring carried out by a clinical oncologist in stereotactic radiosurgery (SRS).

MATERIAL AND METHODS

A sequential audit was conducted of all patients receiving intracranial SRS at our local institution for the first 22 months of a new SRS service. Lesions were contoured first by clinical oncologist then reviewed/edited by the MDT. The initial contour was compared with final contour using Jaccard conformity and geographical miss indices. The dosimetric impact of a contouring change was assessed using plan metrics to both original and final contour. The impact of the contouring review on local relapse, overall survival and radio necrosis rate was evaluated with at least 24 months follow up (24–46 months).

RESULTS

113 patients and 142 lesions treated over 22 months were identified. Mean JCI was 0.92 (0.32–1.00) and 38% needed significant editing (JCI<0.95). Mean GMI was 0.03 (0.0–0.65) and 17% showed significant miss (GMI>0.05). Resection cavities showed more changes, with lower JCI and higher GMI (p<0.05). There was no significant improvement on JCI or GMI shown over time. Dosimetric analysis indicated a strong association of conformity metrics with PTV dose metrics; a 0.1 change in GTV conformity metric association with 6–17% change in dose to 95% of resulting PTV. Greater association was seen in resection cavity suggesting the geographical nature of a typical contouring error gives rise to greater potential change in dose. Clinical outcomes compared well with published series. Median survival was 20 months and local relapse free rate in the treated areas of 0.89 (0.8–0.94) at 40 months, and 0.9 (0.83–0.95) radio-necrosis free rate at 40 months with a median 17 months to developing radio-necrosis for those that did.

CONCLUSION

This work highlights that a MDT contour review adds significant value to SRS and the approach translates into reduced local recurrence rates at our local institution compared with previously published data. Radio-necrosis rates are below 10%. No improvement in clinical oncologist contouring over time was shown indicating a collaborative approach is needed regardless of experience of clinical oncologist. MDT input is recommended in particular in contouring of resection cavities.

Separation and Characterization of Endogenous Nucleosomes by Native Capillary Zone Electrophoresis-Top-Down Mass Spectrometry

We report a novel platform [native capillary zone electrophoresis-top-down mass spectrometry (nCZE-TDMS)] for the separation and characterization of whole nucleosomes, their histone subunits, and post-translational modifications (PTMs). As the repeating unit of chromatin, mononucleosomes (Nucs) are an ∼200 kDa complex of DNA and histone proteins involved in the regulation of key cellular processes central to human health and disease. Unraveling the covalent modification landscape of histones and their defined stoichiometries within Nucs helps to explain epigenetic regulatory mechanisms. In nCZE-TDMS, online Nuc separation is followed by a three-tier tandem MS approach that measures the intact mass of Nucs, ejects and detects the constituent histones, and fragments to sequence the histone. The new platform was optimized with synthetic Nucs to significantly reduce both sample requirements and cost compared to direct infusion. Limits of detection were in the low-attomole range, with linearity of over ∼3 orders of magnitude. The nCZE-TDMS platform was applied to endogenous Nucs from two cell lines distinguished by overexpression or knockout of histone methyltransferase NSD2/MMSET, where analysis of constituent histones revealed changes in histone abundances over the course of the CZE separation. We are confident the nCZE-TDMS platform will help advance nucleosome-level research in the fields of chromatin and epigenetics.

The role of stem cells in uterine involution

Uterine remodeling during pregnancy and repair postpartum are fundamental to the successful propagation of eutherian species. The most drastic remodeling occurs in species with invasively implanting embryos, including humans and mice. During embryo implantation, embryonic trophoblasts breach the epithelium, penetrating into the stroma. Stromal cell decidualization, which is critical for the establishment and maintenance of early pregnancy, occurs throughout the implantation site. Trophoblasts further invade into and remodel uterine spiral arteries, which is necessary for placental formation. The uterus increases in size up to 24-fold, which is largely attributed to myometrial expansion. Uterine changes that occur during pregnancy must then be resolved postpartum. Following parturition, the uterus repairs the remodeled tissue in the process of uterine involution. During involution, the majority of the endometrium is regenerated to replace the tissue that is shed postpartum. The myometrium returns to the pre-gravid state which is thought to occur through apoptosis and autophagy of smooth muscle cells. Although we understand the general process of postpartum uterine involution, the detailed mechanisms, particularly the role of putative stem cells, are poorly understood. This review discusses the evidence for the existence of epithelial, stromal and myometrial stem cells and their role in uterine involution. Gaps in knowledge and areas for future research are also considered. Studies of both postpartum and menstrual uterine repair, which likely involve similar mechanisms, are described under the broad definition of uterine involution. Although the primary focus of this review is human, mouse models are discussed to provide additional information.

Evaluating serious stress in military veterans, their carers and families: a protocol

In 2018, the Armed Forces Covenant Fund Trust (ACFT) allocated approximately £4M to seven UK projects to address serious stress in military veterans, their carers and families. These programmes commenced between May and October 2019 and will conclude in August 2021.

This paper outlines the protocol for the evaluation of the Tackling Serious Stress programme and the novel support provided to grant holders. Entry into the programmes was through multiple routes, including self-referrals with an anticipated sample of approximately 2000 participants. A common outcomes framework was designed to measure outcomes. Grant holders accepted ownership for data collection and quality and were supported through accompanying guidance material.

Veterans were often reluctant to seek support, and the anonymous and confidential nature of the evaluation plus the study team’s military background helped address this. Participants’ voices were a key part in developing the protocol, leading to results to inform policy and highlight success, efficiency and cost effectiveness, and providing markers for future development.

The study provided a reservoir of information. Interim reports indicated compliance with performance indicators and provided timely evidence. Shared learning provided grant holders with an indication of what was helping the beneficiaries and what needed to be improved. The combination of all data sets provided the ACFT with a resource to demonstrate success and insight into projects where improvement was required, and indicators of how to redress these problems. The study protocol provided a platform for building lasting partnerships.

Evaluation of the safety and tolerability of spironolactone in patients with heart failure and chronic kidney disease

BACKGROUND

Spironolactone reduces morbidity and mortality in patients with heart failure (HF) with reduced ejection fraction (EF) and decreases hospitalizations in HF with preserved EF. To minimize the risk of hyperkalemia, patients must have an estimated glomerular filtration rate (eGFR) > 30 mL/min/1.73 m² and potassium < 5.0 mEq/L prior to initiation; however, spironolactone is prescribed outside these parameters. The objective of this study was to evaluate the safety and tolerability of spironolactone in patients with HF and chronic kidney disease (CKD).

METHODS

This single-center, retrospective cohort study evaluated patients ≥ 18 years with HF and CKD stages 3-5 who received ≥ 48 h of spironolactone therapy and were hospitalized from February 2018 to August 2019. The primary outcome was incidence of hyperkalemia (potassium ≥ 5.5 mEq/L).

RESULTS

Overall, 121 patients were evaluated: 52.1% (n = 63) had an EF > 40% and 47.9% (n = 58) had an EF ≤ 40% with 69.4% (n = 84) CKD stage 3, 24.8% (n = 30) stage 4, and 5.8% (n = 7) stage 5. Spironolactone was initiated prior to admission (PTA) for 54.5% (n = 66) of patients, while 45.5% (n = 55) of orders were initiated during hospitalization. Eight patients (6.6%) experienced inpatient hyperkalemia-all with PTA spironolactone. Patients who experienced inpatient hyperkalemia had a numerically lower eGFR that was not statistically significant (35.40 vs. 38.22 mL/min/1.73 m²; p = 0.730). Patients with CKD stage 3 (n = 4) had numerically higher rates of inpatient hyperkalemia than stages 4 (n = 1) or 5 (n = 3) (50%, 12.5%, and 37.5% respectively; p < 0.05).

CONCLUSION

Spironolactone may be safe to initiate in hospitalized patients with HF and CKD; however, appropriateness of therapy must be assessed upon admission to the hospital. Larger studies are needed for conclusive results.

Complex Enterally Tube-Fed Community Patients Display Stable Tolerance, Improved Compliance and Better Achieve Energy and Protein Targets with a High-Energy, High-Protein Peptide-Based Enteral Tube Feed: Results from a Multi-Centre Pilot Study

This pilot study evaluated a high-energy, high-protein, peptide-based, (medium-chain triglycerides) MCT-containing enteral tube feed (Nutrison Peptisorb Plus HEHP^®, Nutricia Ltd., Trowbridge, BA14 0XQ, UK.) containing 1.5 kcal/mL and 7.5 g protein/100 mL. Fifteen community-based, enterally tube-fed adults (42 (SD 16.3) years) received the intervention feed daily for 28 days, with gastrointestinal tolerance, compliance and nutrient intake assessed at baseline and after the intervention period. Incidence and intensity of constipation (p = 0.496), nausea (p = 1.000), abdominal pain (p = 0.366) and bloating (p = 0.250) remained statistically unchanged, yet the incidence and intensity of diarrhoea improved significantly after receiving the intervention feed (Z = −2.271, p = 0.023). Compliance with the intervention feed was significantly greater compared to the patient’s baseline regimens (99% vs. 87%, p = 0.038). Compared to baseline, use of the intervention feed enabled patients to significantly increase total energy (1676 kcal/day (SD 449) to 1884 kcal/day (SD 537), p = 0.039) and protein intake (73 g/day (SD 17) to 89 g/day (SD 23), p = 0.001), allowing patients to better achieve energy (from 88% to 99%, p = 0.038) and protein (from 101% to 121%, p < 0.001) requirements. This pilot study demonstrates that a high-energy, high-protein, peptide-based, MCT-containing enteral tube feed maintains gastrointestinal tolerance and improves compliance, energy and protein intake in complex, enterally tube-fed, community-based adult patients, though more work is recommended to confirm this.

Psychosocial burden and out-of-pocket costs in patients with atopic dermatitis in Ireland

Atopic dermatitis (AD) is one of the most common inflammatory skin diseases in the developed world, affecting 1-3% of the adult population in Europe. This inflammatory disease can have a marked impact on affected individuals, leading to significant impairment in physical wellbeing and quality of life (QoL). The aim of this study was to investigate the psychosocial impact and financial burden of AD on patients in Ireland. To increase our understanding of the psychosocial and financial aspects of AD disease burden in the Irish population, an online survey was designed. The survey was launched by the Irish Skin Foundation, and included questions focusing on disease severity, disease control, psychosocial impact, interrupted sleep, missed work and school days, and financial cost. The survey showed that the impact of AD on QoL was profound. The survey demonstrated that 85% of adults described interrupted sleep, 70% reported social anxiety, 65% avoid exercise and sports, 52% avoid social activities, 52% avoid sexual intimacy and 43% feel they are depressed as a result of their AD. Approximately one-quarter of those surveyed can spend up to €2300 annually on over-the-counter, prescription and alternative treatments. This study has shown the significant impact AD has on patients living in Ireland. It also highlights that out-of-pocket costs for patients is higher compared with previous studies across European countries.

Measuring the therapeutic properties of nursing home environments in the Italian context: findings from a validation and cross-sectional study design

BACKGROUND

The social and the physical features of the nursing home (NH) environment can offer a therapeutic support capable of maximising residents' physical and cognitive functions. A total of 23 instruments evaluating the therapeutic properties of a NH has been documented to date; among them, the most recent and widely used is the Therapeutic Environment Screening Survey for Nursing Homes (TESS-NH) composed of 13 domains and 84 items: higher scores in each domain indicate a higher presence of therapeutic principles. Validating the Italian version of TESS-NH tool and describing the therapeutic properties of Italian NH environments were the aims of this study.

STUDY DESIGN

A validation and a cross-sectional study design, undertaken in 2017.

METHODS

After having ensured the cross-cultural and the conceptual equivalence, together with the face and the content validation, 13 NHs accounting for 1,161 beds and articulated in 31 units have been evaluated with the TESS-NH tool via direct observation by trained researchers. Inter-rater reliability, test-retest, criterion validity, inter-dimension correlations and internal consistency were measured. Descriptive statistics was also calculated.

RESULTS

The inter-rater reliability was Pearson (r) >0.917 for continuous variables and weighted kappa statistics (k) of > 0.779 for non-continuous variables; the test-retest reliability was r > 0.848 and k of > 0.778, respectively. The criterion validity was r > 0.500 between each dimension and the single TESS-NH global item; moreover, correlations among the domains varied from not significant to significantly strong, while the internal consistency resulted in all evaluable dimensions in Cronbach alpha > 0.600. In the involved NH units, the TESS-NH total score was on average 122.19 out of the possible score from 0 to 149 (confidence interval (CI) 95%, 115.89-128.49). 25% of the units (=7) reported a total score of ≤ 113, and another 25% reported scores ≥ 133, thus from poor to excellent therapeutic properties.

CONCLUSION

The TESS-NH tool can be used in Italian facilities to support managers and researchers in evaluating the therapeutic properties of NH environments. Furthermore, the tool can support the evaluation of the effectiveness of interventional studies or quality improvement projects aimed at improving the NH's environment.

P4126Safety of magnetic resonance imaging in patients with non-conditional cardiac implantable electronic devices: A systematic review and meta-analysis

Objective

We aimed to systematically review the literature to identify the adverse events and significance of changes in device function associated with performing MRI in patients with CIEDs

Methods

A comprehensive literature search of the databases was performed between 1980- 2017. Two independent reviewers selected studies and extracted data. A random-effects model was used for meta-analysis.

Results

A total of 7,422 patients underwent 8,865 MRI studies. No death occurred post MRI. Clinical adverse events were extremely rare (mostly less than 1%) and are summarized in Table 1. No significant changes in the pooled mean effect size estimate was noted for the changes in the lead parameters (pacing threshold, sensing and impedance)

Binary outcomes post magnetic resonance imaging in patients with non-conditional cardiac implantable electronic devices Outcome Sample size Number of patients Rate SE LL of CI UL of CI Death 7401 0 0 0 0 0 Atrial arrhythmia 7173 10 0.001 0.0004 0.0007 0.0024 Ventricular arrhythmia 7371 9 0.0012 0.0004 0.0006 0.0022 Oversensing 4981 17 0.0034 0.0008 0.0020 0.0053 Inhibition of pacing 7371 6 0.0008 0.0003 0.0003 0.0016 Lead Failure/Generator Failure 7475/7475 2/8 0.0002/0.0011 0.0001/0.0004 0.0001/0.0005 0.0009/0.002 Power on Reset 1388 105 0.0131 0.0014 0.0107 0.0161 Did not complete scan 6851 13 0.0019 0.0005 0.0011 0.0031 Chest pain 7080 11 0.0021 0.0004 0.0008 0.0027. Lead threshold rise (>0.5v/>50%-A/V) 5076/6246 12/16 0.0024/0.0026 0.0007/0.0006 0.0013/0.0015 0.0040/0.0041 Change in Battery voltage >0.04V 7132 42 0.0061 0.0009 0.0043 0.0079 Sensing decrease >50%-A/V 5087/5834 17/9 0.0033/0.0015 0.0008/0.0005 0.0020/0.0008 0.0052/0.0028 Impedance changes >50ohms/>50% 5810 22 0.0038 0.0008 0.0024 0.0057 Rise in cardiac enzymes 1703 26 0.0152 0.0030 0.0102 0.0219 A, atrial; V, ventricular; SE, standard Error; LL, lower limit; UL, upper limit; CI, Confidence intervals.

Conclusions

MRI in patients with non-conditional CIEDs can be performed with high degree of safety and low rate of clinical events when performed under standardized protocols

Acknowledgement/Funding

None

Exercise-induced syncope and Brugada syndrome

Brugada syndrome (BrS) is a hereditary condition that is characterized by ST elevation, ventricular tachycardia or fibrillation, and sudden cardiac death in otherwise healthy patients. Life-threatening arrhythmias generally occur, while at rest, with fever or during vagotonic states. Exercise is generally not considered a trigger for ventricular arrhythmias or syncope in patients with BrS. We describe a patient who presented with exercise-induced syncope, ventricular tachycardia during an exercise test, and was found to be both genotypically and phenotypically positive for BrS. This case highlights a potentially important role of exercise testing in diagnosing and risk stratifying certain patients with BrS.

Milrinone Does Not Improve Free Flap Survival in Microvascular Surgery

Free flap microvascular surgery involves the transfer of a mobilised tissue flap with complete vascular reanastomosis at the new site. Ischaemia frequently threatens flap survival and may require a return to the operating theatre for anastomotic revision. Arterial spasm and hypoperfusion are recognised as factors in flap ischaemia. Phosphodiesterase inhibitors such as milrinone may improve flap blood flow and possibly flap survival by arterial dilation and increasing cardiac output. To investigate the role of milrinone in this type of surgery, a double-blinded randomised controlled trial was conducted with 88 patients receiving either a milrinone bolus and infusion throughout surgery or placebo (normal saline). We found that milrinone did not improve graft survival, return to theatre rate, or surgically graded arterial spasm, but did require more vasopressor support. We conclude that intraoperative milrinone did not improve flap outcomes in microvascular surgery.

The effect of packaging on consumer eating quality of beef

This experiment examined 3 packaging systems: overwrap packaging using oxygen permeable film (OWP); vacuum skin packaging (VSP) and modified atmosphere packaging (MAP, 80%O₂ and 20%CO₂) on consumer sensory. Three primals from 48 carcasses were aged in vacuum packs for 5, 12 or 40 days. Steaks from longissimus lumborum, gluteus medius and psoas major muscles were packed in OWP, VSP and MAP for 9 days. Untrained consumers scored grilled steaks for tenderness, juiciness, liking of flavour and overall acceptability. Steaks in MAP had 10-12 points lower sensory scores (on a 100 point scale) compared to the OWP, or VSP systems (P < 0.001). The packaging effect was independent of days aging and muscle. It was concluded that high oxygen MAP has the potential to be included as an input variable in the Meat Standards Australia beef grading model. This would be contingent upon research into when the MAP effect occurred and the effect of using different gas mixtures on eating quality.

Factor analysis and Mokken scaling of the Organizational Commitment Questionnaire in nurses

AIMS

To generate an Arabic version of the Organizational Commitment Questionnaire that would be easily understood by Arabic speakers and would be sensitive to Arabic culture.

BACKGROUND

The nursing workforce in Saudi Arabia is undergoing a process of Saudization but there is a need to understand the factors that will help to retain this workforce.

INTRODUCTION

No organizational commitment tools exist in Arabic that are specifically designed for health organizations. An Arabic version of the organizational commitment tool could aid Arabic speaking employers to understand their employees' perceptions of their organizations.

METHODS

Translation and back-translation followed by factor analysis (principal components analysis and confirmatory factor analysis) to test the factorial validity and item response theory (Mokken scaling).

RESULTS

A two-factor structure was obtained for the Organizational Commitment Questionnaire comprising Factor 1: Value commitment; and Factor 2: Commitment to stay with acceptable reliability measured by internal consistency. A Mokken scale was obtained including items from both factors showing a hierarchy of items running from commitment to the organization and commitment to self.

DISCUSSION

This study shows that the Arabic version of the OCQ retained the established two-factor structure of the original English-language version. Although the two factors - 'value commitment' and 'commitment to stay' - repudiate the original developers' single factor claim.

CONCLUSION

A useful insight into the structure of the Organizational Commitment Questionnaire has been obtained with the novel addition of a hierarchical scale.

IMPLICATIONS FOR NURSING POLICY

The Organizational Commitment Questionnaire is now ready to be used with nurses in the Arab speaking world and could be used a tool to measure the contemporary commitment of nursing employees and in future interventions aimed at increasing commitment and retention of valuable nursing staff.

The educational preparation of nurses in a developing economy and patient mortality

BACKGROUND

Most studies have reported that higher levels (baccalaureate degree) of educational attainment by nurses are associated with lower levels of patient mortality. Researchers working in developed economies (e.g. North America and Europe) have almost exclusively conducted these studies. The value of baccalaureate nurse education has not been tested in countries with a developing economy.

METHOD

A retrospective observational study conducted in seven hospitals. Patient mortality was the main outcome of interest. Anonymized data were extracted from nurses and patients from two different administrative sources and linked using the staff identification number that exists in both systems. We used bivariate logistic regression models to test the association between mortality and the educational attainment of the admitting nurse (responsible for assessment and care planning).

RESULTS

Data were extracted for 11 918 (12, 830 admissions) patients and 7415 nurses over the first 6 months of 2015. The majority of nurses were educated in South Asia and just over half were educated to at least bachelor degree level. After adjusting for confounding and clustering, nurse education was not found to be associated with mortality.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Our observations may suggest that in a developing economy, the academic level of nurses' education is not associated with a reduction in patient mortality. Findings should be interpreted with considerable caution but do challenge widely held assumptions about the value of baccalaureate-prepared nurses. Further research focused on nursing education in developing economies is required to inform health policy and planning.

Developing a Stoma Acceptance Questionnaire to improve motivation to adhere to enterostoma self-care

INTRODUCTION

In stoma care, patient education is often weak in terms of improving patients' level of acceptance of living with a stoma. Self-care educational interventions in enterostomal patients, which according to Orem's Theory should take into account these patients' specific needs, require instruments that measure patients' stoma acceptance to improve motivation based on the resumption of activities they used to carry out before having a stoma. The aim of the study was to develop an instrument that measures the level of stoma acceptance to improve motivation to adhere to enterostoma self-care.

METHODS

Aspects that improve stoma acceptance and consequently motivation to adhere to enterostoma self-care were identified through 10 focus groups. In the focus groups, the motivation indicators were grouped, categorised and results entered into a Stoma Acceptance Questionnaire (SAQ). The SAQ was then piloted with 104 enterostomal patients from three general hospitals. To assess the construct validity of the SAQ, Mokken Scaling was used to explore the latent structure of the SAQ. Mokken scaling is a non-parametric method that falls under the umbrella of methods described as item response theories (IRT).

RESULTS

The theme "Living with a stoma"; "Autonomy"; "Support"; "Ability to deal with stoma", plus a common underlying theme: "Stoma acceptance" were dissussed by the Focus Groups. The experts identified the items of the (SAQ) through these themes. Mokken Scaling identified the "resumption of enterostomal patients' normal activities" as a measure of stoma acceptance, thus confirming the construct validity of the SAQ.

CONCLUSIONS

The tool proposed affords a pioneering example of how this gap can be bridged. Indeed, the SAQ could enable nurses adopting a standardized approach for the assessment of enterostomal patients' motivation to resume their normal activities and identify needs linked to this. The SAQ could also be used to measure the effectiveness of psychosocial and educational interventions aimed at improving stoma acceptance.

T regulatory cell phenotypes in peripheral blood and bronchoalveolar lavage from non-asthmatic and asthmatic subjects

BACKGROUND

An unresolved issue in T regulatory cells' cell biology is the lack of consensus on phenotypic markers that accurately define the natural Treg (nTreg) population.

OBJECTIVES

To examine nTreg frequency and functional capacity in healthy controls and their frequency in asthmatic subjects using three different phenotypic strategies. We hypothesized that phenotypically different nTreg are quantitatively and functionally different.

METHODS

Thirty-four healthy, non-asthmatic and 17 asthmatic subjects were studied. Three nTreg phenotypes were defined as follows: nTreg1 (CD4(+) CD25(+) Foxp3(+) ), nTreg2 (CD4(+) CD25(+) CD127(low) Foxp3(+) ), and nTreg3 (CD4(+) CD25(high) Foxp3(+) ). The flow cytometric determination of nTreg frequency in peripheral blood (PB) and bronchoalveolar lavage (BAL) was performed using fluorescently labelled antibodies. Peripheral blood nTreg functional capacity was assessed using a CFSE-based suppression assay.

RESULTS

There was a significantly lower frequency of PB nTreg3 compared to nTreg2 and nTreg1 (P < 0.05). Both nTreg2 and nTreg3 had a significantly greater suppressive capacity than nTreg1 at T responder (Tresp) to nTreg ratios of 16 : 1 up to 1 : 1 (P < 0.01). Asthmatics exhibited a significantly lower PB nTreg3 and nTreg1 frequency than healthy controls (P < 0.05). There were no differences between healthy controls and asthmatic subjects when comparing BAL nTreg frequency.

CONCLUSIONS AND CLINICAL RELEVANCE

Phenotypically different nTreg subsets are quantitatively and functionally different and are variably observed in asthma. The CD4(+) CD25(high) Foxp3(+) phenotype was the least frequent, but demonstrated the greatest suppression, and was significantly lower in PB of asthmatic subjects. Consequently, it is imperative that nTreg phenotypes be clearly defined and that the interpretation of their frequency and function be phenotype specific.