The beauty and complexity of the small heat shock proteins: a report on the proceedings of the fourth workshop on small heat shock proteins

The Fourth Cell Stress Society International workshop on small heat shock proteins (sHSPs), a follow-up to successful workshops held in 2014, 2016 and 2018, took place as a virtual meeting on the 17-18 November 2022. The meeting was designed to provide an opportunity for those working on sHSPs to reconnect and discuss their latest work. The diversity of research in the sHSP field is reflected in the breadth of topics covered in the talks presented at this meeting. Here we summarise the presentations at this meeting and provide some perspectives on exciting future topics to be addressed in the field.

Evaluating the cost implications of integrating SARS-CoV-2 genome sequencing for infection prevention and control investigation of nosocomial transmission within hospitals

BACKGROUND

The COG-UK hospital-onset COVID-19 infection (HOCI) trial evaluated the impact of SARS-CoV-2 whole-genome sequencing (WGS) on acute infection, prevention, and control (IPC) investigation of nosocomial transmission within hospitals.

AIM

To estimate the cost implications of using the information from the sequencing reporting tool (SRT), used to determine likelihood of nosocomial infection in IPC practice.

METHODS

A micro-costing approach for SARS-CoV-2 WGS was conducted. Data on IPC management resource use and costs were collected from interviews with IPC teams from 14 participating sites and used to assign cost estimates for IPC activities as collected in the trial. Activities included IPC-specific actions following a suspicion of healthcare-associated infection (HAI) or outbreak, as well as changes to practice following the return of data via SRT.

FINDINGS

The mean per-sample costs of SARS-CoV-2 sequencing were estimated at £77.10 for rapid and £66.94 for longer turnaround phases. Over the three-month interventional phases, the total management costs of IPC-defined HAIs and outbreak events across the sites were estimated at £225,070 and £416,447, respectively. The main cost drivers were bed-days lost due to ward closures because of outbreaks, followed by outbreak meetings and bed-days lost due to cohorting contacts. Actioning SRTs, the cost of HAIs increased by £5,178 due to unidentified cases and the cost of outbreaks decreased by £11,246 as SRTs excluded hospital outbreaks.

CONCLUSION

Although SARS-CoV-2 WGS adds to the total IPC management cost, additional information provided could balance out the additional cost, depending on identified design improvements and effective deployment.

First Dark Matter Search with Nuclear Recoils from the XENONnT Experiment

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03)  ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3)  events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47}  cm^{2} for a WIMP mass of 28  GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

Searching for Heavy Dark Matter near the Planck Mass with XENON1T

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17}  GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

Impact of supplementary air filtration on aerosols and particulate matter in a UK hospital ward: a case study

BACKGROUND

Aerosol spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a major problem in hospitals, leading to an increase in supplementary high-efficiency particulate air filtration aimed at reducing nosocomial transmission. This article reports a natural experiment that occurred when an air cleaning unit (ACU) on a medicine for older people ward was switched off accidentally while being commissioned.

AIM

To assess aerosol transport within the ward and determine whether the ACU reduced airborne particulate matter (PM) levels.

METHODS

An ACU was placed in a ward comprising two six-bedded bays plus three single-bed isolation rooms which had previously experienced several outbreaks of coronavirus disease 2019. During commissioning, real-time measurements of key indoor air quality parameters (PM1-10, CO2, temperature and humidity) were collected from multiple sensors over 2 days. During this period, the ACU was switched off accidentally for approximately 7 h, allowing the impact of the intervention on PM to be assessed.

FINDINGS

The ACU reduced the PM counts considerably (e.g. PM1 65.5-78.2%) throughout the ward (P<0.001 all sizes), with positive correlation found for all PM fractions and CO2 (r=0.343-0.817; all P<0.001). PM counts rose/fell simultaneously when the ACU was off, with correlation of PM signals from multiple locations (e.g. r=0.343-0.868; all P<0.001) for particulates <1 μm).

CONCLUSION

Aerosols migrated rapidly between the various ward subcompartments, suggesting that social distancing alone cannot prevent nosocomial transmission of SARS-CoV-2 as this fails to mitigate longer-range (>2 m) transmission. The ACU reduced PM levels considerably throughout the ward space, indicating its potential as an effective intervention to reduce the risk posed by infectious airborne particles.

331 THE USE OF BODY MASS INDEX IN PREDICTING ORTHOSTATIC HYPOTENSION IN OLDER ADULTS

Background

The presence of Orthostatic Hypotension (OH) is known to be associated with an increased mortality risk. Previous Irish research has shown that elevated Body Mass Index (BMI) may be protective against OH, with overweight and obese patients having significantly smaller Systolic Blood Pressure (SBP) drops during Head-Up-Tilt (HUT) Testing.

Methods

Demographics, including age, height and weight, were obtained retrospectively from all head up tilt testing performed in a tertiary Irish hospital between 2000 and 2021. All incomplete records were excluded. A total of 4,717 patients were analysed. Linear regression models were used to examine the relationship between BMI and change in tilt SBP.

Results

2,089 males and 2,628 females over the age of 60 years old were examined. The mean age is 77 years ± 7.8 (S.D.), with majority (51.5%) of the cohort overweight or obese. 69.7% of individuals demonstrated OH. The mean change in tilt SBP was –7mmHg in the underweight and healthy weight group, and –10mmHg in the overweight or obese group. The linear regression model established that BMI significantly predicted a change in tilt SBP (beta=0.394, 95% CI: 0.235 to 0.554, p&lt;0.001), but remains a poor predictive variable (R2=0.004) for this cohort. This correlation was similar for both genders (male: r=0.08, female: r=0.07).

Conclusion

Our findings confirmed a correlation between BMI and its predictive impact on OH in older adults. Future studies should explore targeted populations with multivariate analysis, taking into consideration age and gender, to reduce the heterogeneity of data.

220 RELATIONSHIP BETWEEN HEIGHT AND SYSTOLIC BLOOD PRESSURE IN OLDER ADULTS

Background

Hypertension is common amongst older adults in Ireland and is a major risk factor for both ischaemic and haemorrhagic stroke. Several studies have investigated the relationship between height and hypertension, however results have been inconsistent. In our Irish tertiary hospital patients undergoing tilt table testing have resting blood pressure measured prior to the test, and height recorded. Our aim was to assess whether there is a relationship between height and resting Systolic Blood Pressure (SBP) in patients aged over 60 years.

Methods

All tilt table test results between 2000 and 2021 in a single centre were reviewed retrospectively, collecting data on age, height and resting SBP. Any incomplete records were excluded, as were those from patients under 60 years old. Linear regression modelling was used to assess relationship between height and resting SBP.

Results

A total of 4,729 complete records were included for patients over 60 years old. 2630 (61.5%) of the patients were female. Mean age was 77 ± 7.8 years. 57.7% patients had either an elevated resting systolic and/or diastolic BP ≥130/80 and 28.4% ≥140/90. The linear regression model established that while height could be used to predict resting systolic blood pressure (beta=-0.166, 95% CI: –0.219 to –0.113, p&lt;0.001), height only accounted for 0.8% of variability in resting SBP (R2 = 0.008).

Conclusion

Our large dataset establishes an association but no meaningful causation between height and resting systolic blood pressure. Current antihypertensive treatment was not recorded, which may have affected the results. Future studies will include further multivariate analysis accounting for antihypertensive use and other factors that may impact hypertension such as age, weight and gender.

353 FACTORS ASSOCIATED WITH ADVERSE OUTCOMES IN OLDER ADULTS DIRECTLY DISCHARGED FROM THE EMERGENCY DEPARTMENT

Background

Older adults attend the Emergency Department (ED) frequently. Over 40% are directly discharged from the ED. The risk of adverse outcomes is high following discharge including unplanned ED return, institutionalisation, and mortality. The purpose of this study was to highlight factors that predict these adverse outcomes.

Methods

A secondary analysis was completed of SOAED (a prospective cohort study examining screening instruments to predict adverse outcomes for undifferentiated older adults attending the ED) and OPTIMEND (randomised control trial examining the effectiveness of an intervention by a team of Health and Social Care Professionals along with usual care and compared this to standard ED care alone). Inclusion criteria were adults aged 65 years and over presenting to ED at a University Teaching Hospital with medical complaints and a Manchester Triage System category 2–5.

Results

Three-hundred and nine patients were discharged directly from ED (mean age 80 years; 58% female). 96 patients re-attended ED within 6 months. 66 patients were re-hospitalised within 6 months. 16 patients died within six months of discharge. 63% of the discharged patients screened positive for frailty measured by PRISMA-7 (3 or more). Relative risk ratio analysis confirmed that the risk of revisiting a hospital was 1.241 times for patients that scored frail compared to those who scored not frail. The risk of mortality was 1.075 times for patients that scored frail compared to those who scored not frail. The risk of being admitted to a nursing home was 1.146 times for patients that scored frail compared to those who scored not frail.

Conclusion

Older people have a high ED re-attendance rate of 31% after an index visit. Frailty (scored on PRISMA-7) is a significant predictor of adverse outcomes. Focused screening and intervention for frail patients who attend the ED should be a priority.

Search for New Physics in Electronic Recoil Data from XENONnT

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3)  events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

SAA fibrils involved in AA amyloidosis are similar in bulk and by single particle reconstitution: A MAS solid-state NMR study

AA amyloidosis is one of the most prevalent forms of systemic amyloidosis and affects both humans and other vertebrates. In this study, we compare MAS solid-state NMR data with a recent cryo-EM study of fibrils involving full-length murine SAA1.1. We address the question whether the specific requirements for the reconstitution of an amyloid fibril structure by cryo-EM can potentially yield a bias towards a particular fibril polymorph. We employ fibril seeds extracted from in to vivo material to imprint the fibril structure onto the biochemically produced protein. Sequential assignments yield the secondary structure elements in the fibril state. Long-range DARR and PAR experiments confirm largely the topology observed in the ex-vivo cryo-EM study. We find that the β-sheets identified in the NMR experiments are similar to the β-sheets found in the cryo-EM study, with the exception of amino acids 33–42. These residues cannot be assigned by solid-state NMR, while they adopt a stable β-sheet in the cryo-EM structure. We suggest that the differences between MAS solid-state NMR and cryo-EM data are a consequence of a second conformer involving residues 33–42. Moreover, we were able to characterize the dynamic C-terminal tail of SAA in the fibril state. The C-terminus is flexible, remains detached from the fibrils, and does not affect the SAA fibril structure as confirmed further by molecular dynamics simulations. As the C-terminus can potentially interact with other cellular components, binding to cellular targets can affect its accessibility for protease digestion.

Airborne protection for staff is associated with reduced hospital-acquired COVID-19 in English NHS Trusts

Introduction

The rate of hospital-acquired coronavirus disease 2019 has reduced from 14.3% to 4.2% over the last year, but substantial differences still exist between English National Health Service (NHS) hospital trusts.

Methods

This study assessed rates of hospital-acquired infection (HAI), comparing NHS hospital trusts using airborne respiratory protection (e.g. FFP3 masks) for all staff, as a marker of measures to reduce airborne spread, with NHS hospital trusts using mainly droplet precautions (e.g. surgical masks).

Results/discussion

The use of respiratory protective equipment was associated with a 33% reduction in the odds of HAI in the Delta wave, and a 21% reduction in the odds of HAI in the Alpha wave (P<0.00001). It is recommended that all hospitals should prioritize airborne mitigation.

233 BISPHOSPHONATES: ANOTHER COMPLEX DRUG TO PRESCRIBE

Background

Bisphosphonates provide effective treatment for osteoporosis. They accumulate a bone reservoir lasting for 3 years and beyond. The 2021 NICE guidelines recommend a medication review and a ‘drug holiday’ after 5 years of oral bisphosphonate therapy for low-fracture risk patients. Continuing treatment for high risk individuals is advised: age=/&gt;75, previous hip or vertebral fracture, one or more fractures during treatment, recent DEXA scan with T score =/&lt;−2.5, and/or current treatment with oral glucocorticoids. This retrospective audit aimed to assess compliance with NICE guidelines in a primary care setting.

Methods

Data were collected using the Health One online medical record system in an urban general practice. Inclusion criteria: all patients =/&gt; 65 years old, prescribed oral bisphosphonate therapy for osteoporosis for &gt;5 years. Exclusion criteria: deceased, did not attend clinic &gt;1 year, patients on bisphosphonate treatment for conditions other than osteoporosis.

Results

137 patients with a history of bisphosphonate therapy were identified. 76 patients were on bisphosphonate treatment for greater than 5 years. Of the 76 patients, 33 were classified as low-fracture risk and appropriately commenced a drug holiday, while 22 correctly remained on bisphosphonates due to a high fracture risk. The remaining 21 patients inappropriately continued therapy without receiving a medication review, repeat DEXA or fracture-risk assessment.

Conclusion

One third of patients on bisphosphonates beyond 5 years were not assessed for a drug holiday. The aim of a bisphosphonate ‘drug holiday’ is to reduce poly-pharmacy and prevent rare but serious long-term adverse events (such as atypical fractures, osteonecrosis of the jaw, gastric cancer and atrial fibrillation). Factors which had an impact on inappropriate prescribing should be assessed. Incorporating computer-based prescribing alerts could support safe prescribing practices.

241 IMPLEMENTATION OF AN INTRACEREBRAL CEREBRAL HAEMORRHAGE CARE BUNDLE

Background

Mortality for Intracerebral haemorrhage (ICH) is 31% (Irish National Audit Stroke, 2019). An ICH care bundle focusing on acute anticoagulation reversal, blood pressure lowering, and a neurosurgical care pathway was associated with improved survival. Translating evidence-based medicine into clinical practice is challenging. The aim of this study was to determine feasibility and outcomes of implementation of a care bundle.

Methods

An ICH care bundle was developed using an iterative process involving expert stakeholder review of the evidence-based literature. A pre-and-post quasi-experimental research design was employed to evaluate this intervention. Baseline data were collected before implementation (January 2016-June 2018). Implementation took place in a staged manner in a single university teaching hospital with multiple ‘Plan Do Study Act cycles’ (June 2018 to January 2021). Data on compliance, process measures and outcomes were collected.

Results

Systolic blood pressure (first 24-hours) and anticoagulant reversal were significantly better controlled post-implementation (χ2 (1, N = 91) = 5.34, P = 0.02), (χ2 (1, N = 25) = 5.85, P = 0.016), respectively. DNAR orders were significantly lower in the post-implementation group (χ2 (1, N = 25) = 5.85, P = 0.029). However, ‘Do Not Actively Resuscitate’ status did not significantly differ when accounting for low GCS as a surrogate measure for poor prognosis (χ2 (1, N = 34) = 0.00, P = 0.966). Modified Rankin Scale on discharge did not differ significantly pre-and-post-implementation (z = −0.075, P = 0.94). A greater proportion of patients survived in the post-implementation group; however, this was not statistically significant (χ2 (1, N = 133) = 0.77, P = 0.38). Length of stay significantly increased post implementation.

Conclusion

An ICH care bundle was developed based on expert stakeholder feedback. The feasibility of implementing this bundle of care was demonstrated in a real-world clinical practice setting. A cluster-randomized trial or a large registry study is the next step to evaluate the overall impact of this care bundle on patient outcomes.

Phosphorylation activates the yeast small heat shock protein Hsp26 by weakening domain contacts in the oligomer ensemble

Hsp26 is a small heat shock protein (sHsp) from S. cerevisiae. Its chaperone activity is activated by oligomer dissociation at heat shock temperatures. Hsp26 contains 9 phosphorylation sites in different structural elements. Our analysis of phospho-mimetic mutations shows that phosphorylation activates Hsp26 at permissive temperatures. The cryo-EM structure of the Hsp26 40mer revealed contacts between the conserved core domain of Hsp26 and the so-called thermosensor domain in the N-terminal part of the protein, which are targeted by phosphorylation. Furthermore, several phosphorylation sites in the C-terminal extension, which link subunits within the oligomer, are sensitive to the introduction of negative charges. In all cases, the intrinsic inhibition of chaperone activity is relieved and the N-terminal domain becomes accessible for substrate protein binding. The weakening of domain interactions within and between subunits by phosphorylation to activate the chaperone activity in response to proteotoxic stresses independent of heat stress could be a general regulation principle of sHsps.

247 BENCHMARKING STROKE SERVICES TO INFORM A QUALITY IMPROVEMENT INIAITIVE

Background

Stroke is a leading cause of death and disability in Ireland. Continuous audit and quality improvement is essential in the delivery of stroke care where the evidence basis is constantly changing. This helps to ensure the delivery of high quality stroke care and compliance with evidenced based guidelines. We aimed to assess stroke care at an Irish university teaching hospital.

Methods

Patients with a HIPE discharge diagnosis of Cerebral Infarction or Cerebral Haemorrhage (1st January-31st December 2019) were identified through both the HIPE database and the institutional Stroke Portal. Data was benchmarked against national (Irish National Audit of Stroke 2019) and international (6th SSNAP Annual Report; American Heart Association, 2013) practice and used to inform a quality improvement strategy.

Results

419 patients were included (56.6% male, median 57 years). 75.9% were aged 65 years or older. We compared favourably with Irish National Audit of Stoke national indicators on the following: thrombolysis rates-10%; median door to needle time-60 mins; stroke unit admissions- 78.5%; median duration of symptoms- 3 hours 6 minutes; swallow assessment- 81.1%; in-patient mortality- 10.5%; rates of institutionalisation- 3.8%. Areas identified for improvement were: thrombectomy rates- 1.9%; median length of stay- 12 days; door to imaging time- median 104 minutes; mood screening- 11.5%.

Conclusion

International and national data is a useful benchmark against which local hospitals can assess the quality of their service. By completing this quality improvement initiative we identified areas to target resources in our centre, including mood screening, swallow screening, thrombectomy rates, length of stay and time to neuroimaging. An ongoing quality improvement process using ‘PDSA’ methodology is being carried out with an annual audit to monitor progress.

235 THROMBOLYSIS DOSING AND WEIGHT ESTIMATION IN ACUTE STROKE: A SINGLE CENTRE AUDIT

Background

Stroke is a leading cause of death and disability. Thrombolysis with intravenous (IV) alteplase is the mainstay management of ischaemic stroke. It has a narrow therapeutic window with a high potential for adverse outcomes such as intracranial haemorrhage. The efficacy of alteplase is time and dose dependent with weight-based dosing. National clinical guidelines recommend a dose of 0.9 mg/kg, up to a maximum of 90 mg. (Irish Heart Foundation Council for Stroke 2015). In most hospitals in Ireland however, patients are not weighed prior to thrombolysis. Time pressure and lack of available suitable equipment are factors.

Methods

This retrospective clinical audit evaluated the dosing of alteplase, estimated and actual weight for a convenience sample of stroke thrombolysis patients treated between 2016–2020 at an Irish University Teaching Hospital.

Results

107 patients were audited (62 males, 45 females). Actual and estimated weights were available in 92/107. Weight was not documented (n = 15) due to severe stroke/palliative management (n = 6) or omission (n = 9). 21% (19/92) received the correct dose of 0.9 mg/kg. A further 54% (50/92) received a dose within the range of 0.81–0.99 mg/kg (±10%). 25% received a dose outside this range (&gt; ± 10%). 11% (10/92) were under-thrombolysed and 14% (13/92) over-thrombolysed. 17/92 patients had an intracranial haemorrhage. 35% (n = 6/17) of patients who had an intracranial haemorrhage received a higher dose of thrombolysis (&gt;10%).

Conclusion

A quarter of patients received inappropriate dosing of alteplase that was outside the range of ±10% of 0.9 mg/kg. While stroke thrombolysis must be completed urgently, an accurate weight should be determined to avoid errors in dosing. A process evaluation of stroke thrombolysis would provide information on how best to incorporate an objective means of weight measurement without delaying treatment.

236 PREDICTORS OF ADVERSE OUTCOMES IN OLDER PATIENTS DISCHARGED DIRECTLY FROM THE EMERGENCY DEPARTMENT

Background

Over 40% of older patients are discharged directly from the Emergency Department (ED) and this cohort is at increased risk of adverse outcomes.

The purpose of this study was to explore the factors that predict future adverse outcomes in this cohort to inform practice, resource planning and policy.

Methods

A secondary analysis of the OPTIMEND, a single-centre, randomized-controlled trial was completed. OPTIMEND examined the effectiveness of an intervention by a team of Health and Social Care Professionals along with usual care and compared this to standard ED care alone (Dec 2018-May 2019). The inclusion criteria were adults aged 65 years and over presenting to the ED at a University Teaching Hospital with medical complaints and a Manchester Triage System category 2–5.

Results

220 patients were included (median age 79 years; 62% female). Median length of stay in ED was 5.5 hrs. 70 patients re-attended the ED within 6 months with 43 re-hospitalised within 6 months. 9 patients died within six months of discharge.

Multivariant logistic regression was completed. Age was the only independent predictor of mortality within six months of discharge {Odds Ratio (OR) 1.15, p = 0.044}. Past hospitalisation (&lt;6 months) was associated with a lower likelihood of ED re-attendance, and rehospitalization within six months of discharge (OR: 0.452 p = 0.022; OR:0.442, p = 0.046; respectively). Clinical Frailty Score was associated with a significantly higher likelihood of rehospitalization (OR:1.48, p = 0.031) but not with ED revisits (OR: 1.235, p = 0.165).

Conclusion

Older people have a high ED re-attendance rate of 33% after an index visit with 20% hospitalized subsequently. Frailty is a significant predictor of rehospitalisation. Rapid and targeted intervention for frail patients who reattend the ED should be a priority for the integrated care program to enhance admission avoidance.

234 THE IMPACT OF OLDER AGE ON CLINICAL OUTCOMES DURING THE FIRST WAVE OF THE COVID-19 PANDEMIC

Background

Severe acute respiratory coronavirus 2 (SARS-CoV-2) was first recorded in Ireland in February 2020. Several studies have explored the association between age and SARS-CoV-2, showing that there were poorer outcomes in older people. Our objective was to evaluate the impact of age on outcomes such as hospital length of stay, mortality, and re-hospitalisation.

Methods

We performed a single-centre, retrospective observational cohort study, using an electronic microbiology database of recorded index admissions of SARS-CoV-2 positive patients aged 65 years and older during SARS-CoV-2 wave one (March 1^st to May 31^st 2020). PCR testing of nasopharyngeal and/or sputum samples was used to confirm positivity. Our clinical outcomes measured included hospital length of stay, mortality and re-admission rate within 6 months.

Results

153 patients 65 years and above were admitted. The male to female ratio was 1.3 with 90% admitted medically. 79 patients were aged between 65–79 years; 84 patients ≥80 years; and 12 patients ≥90 years. Mortality was 25%, 31% and 42%, respectively. Median length of stay remained 14 days for ages 65–89 rising to 17.5 days for those ≥90 years. Re-hospitalisation rates at 6 months were similar for ages 65–79 and 89–89 years at 42% and 40%, respectively. One patient (14%) over 90 years was re-hospitalised.

Conclusion

SARS-CoV-2 has disproportionately impacted on general medical services treating older hospitalised people. In our centre, mortality for patients ≥65 years was 28.1% which compared favourably with 35.6% internationally as outlined by Victor et al. (2020) based on Spanish data. Treatment of SARS-CoV-2 is not futile in older patients with 58% of nonagenarians and 69% of octogenarians surviving, however re-hospitalisation rates are high at 40%. A targeted approach to discharge support via integrated care may ameliorate this.

584 Novel Methods of Detecting Tumour Margins in Gastrointestinal Cancer Surgery

Aim

Gastrointestinal (GI) cancers account for 26% of global cancer incidence with prevalence projected to rise exponentially due to the ageing population and lifestyle choices. Surgical resection is the mainstay of treatment to remove the cancer in its entirety to achieve an R0 resection. Positive margins, when cancerous tissue has been left in situ, is associated with increased morbidity and mortality. Current margin assessment involves histopathological analysis, after resection of the specimen. Diffuse Reflectance Spectroscopy (DRS) and Hyperspectral Imaging (HSI) are novel imaging techniques that have the potential to provide real-time assessment of cancer margins intra-operatively to reduce the incidence of positive resection margins and improve patient outcomes. The aim of this review is to assess the current state of evidence for the use of novel imaging techniques in GI cancer margin assessment.

Method

A literature review was conducted of studies using DRS and HSI in GI cancers in adult patients, published from inception to October 2020.

Results

A total of 15 studies were analysed, nine of which used DRS and six used HSI and the majority of studies were performed ex-vivo. Current image acquisition techniques and processing algorithms vary greatly. The sensitivity and specificity of DRS ranged from 0.90-0.98 and 0.88-0.95 respectively and for HSI 0.63-0.98 and 0.69-0.98, respectively across five types of GI cancers.

Conclusions

DRS and HSI are novel imaging techniques, currently in their infancy but the outlook is promising. With further research focused on standardising methodology and in-vivo settings, DRS and HSI could transform intra-operative margin assessment in GI cancers.

Investigation and control of an outbreak due to a contaminated hospital water system, identified following a rare case of Cupriavidus pauculus bacteraemia

BACKGROUND

Cupriavidus pauculus is rare cause of clinical infection. We describe an outbreak of C. pauculus and other Gram-negative bacteraemias in a paediatric haemato-oncology unit secondary to a contaminated water supply and drainage system.

AIM

To describe the investigation and control measures implemented for a waterborne infection outbreak in a new build hospital.

METHODS

Extensive water testing from various points within the water system was undertaken. Taps, showerheads and components including flow straighteners underwent microbiological analysis. Drains were also swabbed. Surveillance for Gram-negative infections was established on the unit.

FINDINGS

Water testing revealed widespread contamination of the water and drainage system. Outlets were also heavily contaminated, including flow straighteners. Drains were found to have underlying structural abnormalities. Water testing enabled us to detect high-risk components within the water system such as the expansion vessels and outlets and the results assisted with hypotheses generation. Review of commissioning data and risk assessments revealed extensive risks present within the water system prior to and after hospital opening.

CONCLUSION

Careful design, adequate control measures and maintenance are essential for hospital water systems in order to prevent infections due to waterborne organisms. We discuss what can be learned from this incident with a view to future prevention.

Investigation of two cases of Mycobacterium chelonae infection in haemato-oncology patients using whole-genome sequencing and a potential link to the hospital water supply

BACKGROUND

Haemato-oncology patients are at increased risk of infection from atypical mycobacteria such as Mycobacterium chelonae which are commonly found in both domestic and hospital water systems.

AIMS

To describe the investigation and control measures following two patient cases of M. chelonae and positive water samples in the study hospital.

METHODS

Water testing was undertaken from outlets, storage tanks and mains supply. Whole-genome sequencing (WGS) was used to compare patient and positive water samples. The subsequent infection control measures implemented are described.

FINDINGS

The WGS results showed two main populations of M. chelonae within the group of sampled isolates. The results showed that the patient strains were unrelated to each other, but that the isolate from one patient was closely related to environmental samples from water outlets, supporting nosocomial acquisition.

CONCLUSIONS

WGS was used to investigate two patient cases of M. chelonae and positive water samples from a hospital water supply. Relevant control measures and the potential for chemical dosing of water systems to enhance proliferation of atypical mycobacteria are discussed.

Features of the Energy Spectrum of Cosmic Rays above 2.5×10^{18} eV Using the Pierre Auger Observatory

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18}  eV based on 215 030 events. New results are presented: at about 1.3×10^{19}  eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19}  eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18}  eV is [5.66±0.03(stat)±1.40(syst)]×10^{53}  erg Mpc^{-3}.

Potential infection control risks associated with chilled beam technology: experience from a UK hospital

Energy efficiency technologies are now a feature in hospital design, with active chilled beams an example of one in use worldwide. Such innovations have clear benefits but there is a paucity of information with respect to any infection control risks. We describe our experience of chilled beam technology from one of our hospitals where we faced challenges with cleaning and episodes of water ingress including condensation. We highlight the importance of infection control risk assessment in relation to new technologies and the implementation of appropriate risk mitigation.

Mass and the Dangers of Syncope

Introduction Syncope is defined as a transient, self-limited loss of consciousness with an inability to maintain postural tone that is followed by spontaneous recovery. We revisit situational syncope focusing on one situation, Mass. Methods We interrogated our electronic syncope database for key terms associated with situational syncope. From the most commonly encountered situation, Mass, we interrogated the results of tilt testing performed to identify evidence of orthostatic hypotension. Results There were 110 cases of situational syncope identified with 56.3% (n=62) taking place at mass. All had tilt table testing performed and 15.4% (n=17) had evidence of orthostatic hypotension. Conclusion The multiple sudden changes in position during mass from sitting to kneeling to standing can precipitate an episode of orthostatic hypotension. Consideration should be given as to whether it is safe for older mass goers to be subjected to such significant orthostatic stress.

Regulation of small heat-shock proteins by hetero-oligomer formation

Small heat-shock proteins (sHsps) compose the most widespread family of molecular chaperones. The human genome encodes 10 different sHsps (HspB1-10). It has been shown that HspB1 (Hsp27), HspB5 (αB-crystallin), and HspB6 (Hsp20) can form hetero-oligomers in vivo However, the impact of hetero-oligomerization on their structure and chaperone mechanism remains enigmatic. Here, we analyzed hetero-oligomer formation in human cells and in vitro using purified proteins. Our results show that the effect of hetero-oligomer formation on the composition of the sHsp ensembles and their chaperone activities depends strongly on the respective sHsps involved. We observed that hetero-oligomer formation between HspB1 and HspB5 leads to an ensemble that is dominated by species larger than the individual homo-oligomers. In contrast, the interaction of dimeric HspB6 with either HspB1 or HspB5 oligomers shifted the ensemble toward smaller oligomers. We noted that the larger HspB1-HspB5 hetero-oligomers are less active and that HspB6 activates HspB5 by dissociation to smaller oligomer complexes. The chaperone activity of HspB1-HspB6 hetero-oligomers, however, was modulated in a substrate-specific manner, presumably due to the specific enrichment of an HspB1-HspB6 heterodimer. These heterodimeric species may allow the tuning of the chaperone properties toward specific substrates. We conclude that sHsp hetero-oligomerization exerts distinct regulatory effects depending on the sHsps involved.

The structure and oxidation of the eye lens chaperone αA-crystallin

The small heat shock protein αA-crystallin is a molecular chaperone important for the optical properties of the vertebrate eye lens. It forms heterogeneous oligomeric ensembles. We determined the structures of human αA-crystallin oligomers by combining cryo-electron microscopy, cross-linking/mass spectrometry, NMR spectroscopy and molecular modeling. The different oligomers can be interconverted by the addition or subtraction of tetramers, leading to mainly 12-, 16- and 20-meric assemblies in which interactions between N-terminal regions are important. Cross-dimer domain-swapping of the C-terminal region is a determinant of αA-crystallin heterogeneity. Human αA-crystallin contains two cysteines, which can form an intramolecular disulfide in vivo. Oxidation in vitro requires conformational changes and oligomer dissociation. The oxidized oligomers, which are larger than reduced αA-crystallin and destabilized against unfolding, are active chaperones and can transfer the disulfide to destabilized substrate proteins. The insight into the structure and function of αA-crystallin provides a basis for understanding its role in the eye lens.

Evaluation of VIDAS Listeria monocytogenes II (LMO2) Immunoassay Method for the Detection of Listeria monocytogenes in Foods: Collaborative Study

A multilaboratory study was conducted to compare the VIDAS®Listeria monocytogenes II (LMO2) immunoassay and the standard cultural methods for the detection of Listeria monocytogenes in foods. Five food types—vanilla ice cream, brie cheese, cooked roast beef, frozen green beans, and frozen tilapia fish—at 3 levels were analyzed by each method. A total of 26 laboratories representing government and industry participated. In this study, 1404 test portions were analyzed of which 1152 were used in the statistical analysis. There were 448 positive by the VIDAS LMO2 assay and 457 positive by the standard culture methods. A χ2 analysis of each of the 5 food types, at the 3 inoculation levels tested, was performed. The resulting χ2 value, 0.36, indicates that overall, there are no statistical differences between the VIDAS LMO2 assay and the standard methods at the 5% level of significance.

Enumeration of Total Coliforms and E. coli in Foods by the SimPlate® Coliform and E. coli Color Indicator Method and Conventional Culture Methods: Collaborative Study

The relative effectiveness of the SimPlate® Coliform and E. coli Color Indicator (CEc-CI) method was compared to the AOAC 3-tube Most Probable Number (MPN) methods for enumerating and confirming coliforms and Escherichia coli in foods (966.23 and 966.24). In this study, test portions were prepared and analyzed according to the conditions stated in both the AOAC methods and SimPlate directions for use. Six food types were artificially contaminated with coliform bacteria and E. coli: frozen burritos, frozen broccoli, fluid pasteurized milk, whole almond nut meats, cheese, and powdered cake mix. Method comparisons were conducted. Overall, the SimPlate method demonstrated &lt;0.3 log difference for total coliform and E. coli counts compared to the AOAC reference methods for the majority of food types and levels analyzed. In all cases, the repeatability and reproducibility of the SimPlate CEc-CI method were not different from those of the reference methods and in certain cases, were statistically better than those of the AOAC 3-tube MPN methods. These results indicate that the SimPlate CEc-CI method and the reference culture methods are comparable for enumeration of both total coliforms and E. coli in foods.

Management of growth failure and growth hormone deficiency after pediatric allogeneic HSCT: Endocrinologists are of importance for further guidelines and studies

Growth failure (GF) is a frequent problem after pediatric allogeneic hematopoietic stem cell transplantation (HSCT). Growth hormone deficiency (GHD) occurs in 20 to 85%, but published data on the efficacy of growth hormone treatment (GHT) are conflicting. Currently, there are no recommendations on screening for and treatment of GHD after HSCT. We aimed to describe the management of endocrine follow-up (FU)and details of GHT within European Society for Blood and Marrow Transplantation (EBMT) centers.In a retrospective questionnaire study, all EBMT centers performing pediatric HSCT were invited. Results were evaluated in correlation with the structure of endocrine aftercare (HSCT-clinicians and endocrinologists).The majority of centers (80%) reported endocrine FU by an endocrinologist - either within the HSCT-center or in a separate endocrine clinic. Fifty-four percent reported FU outside of the HSCT-center. As diagnostic tests the insulin-like growth factor IGF-I and insulin-like growth factor binding protein IGFBP3, insulin tolerance test and arginine stimulation test were most frequently used. Sixty-four percent of centers performed GHT and endocrinologists were more likely to prescribe GH (74%) compared to HSCT-clinicians (33%). The most frequent indication for GHT was GHD in 60%, with a distinct different approach of endocrinologists in comparison with HSCT-clinicians.Our study reveals substantial variation in practice and emphasizes the need for endocrine aftercare performed by dedicated endocrinologists in close collaboration with the HSCT-center. Our results indicate that the management of GHT depends on the structure of endocrine aftercare, which is important for the future development and distribution of studies and guidelines.

Mg2+ -free ATP regulates the processivity of native cytoplasmic dynein

Cytoplasmic dynein, a microtubule-based motor protein, is responsible for many cellular functions ranging from cargo transport to cell division. The various functions are carried out by a single isoform of cytoplasmic dynein, thus requiring different forms of motor regulation. A possible pathway to regulate motor function was revealed in optical trap experiments. Switching motor function from single steps to processive runs could be achieved by changing Mg²⁺ and ATP concentrations. Here, we confirm by single molecule total internal reflection fluorescence microscopy that a native cytoplasmic dynein dimer is able to switch to processive runs of more than 680 consecutive steps or 5.5 μm. We also identified the ratio of Mg²⁺ -free ATP to Mg.ATP as the regulating factor and propose a model for dynein processive stepping.

DIAGNOSIS OF ENDOCRINE DISEASE: Congenital hypothyroidism: update and perspectives

Congenital hypothyroidism (CH) may be primary, due to a defect affecting the thyroid gland itself, or central, due to impaired thyroid-stimulating hormone (TSH)-mediated stimulation of the thyroid gland as a result of hypothalamic or pituitary pathology. Primary CH is the most common neonatal endocrine disorder, traditionally subdivided into thyroid dysgenesis (TD), referring to a spectrum of thyroid developmental abnormalities, and dyshormonogenesis, where a defective molecular pathway for thyroid hormonogenesis results in failure of hormone production by a structurally intact gland. Delayed treatment of neonatal hypothyroidism may result in profound neurodevelopmental delay; therefore, CH is screened for in developed countries to facilitate prompt diagnosis. Central congenital hypothyroidism (CCH) is a rarer entity which may occur in isolation, or (more frequently) in association with additional pituitary hormone deficits. CCH is most commonly defined biochemically by failure of appropriate TSH elevation despite subnormal thyroid hormone levels and will therefore evade diagnosis in primary, TSH-based CH-screening programmes. This review will discuss recent genetic aetiological advances in CH and summarize epidemiological data and clinical diagnostic challenges, focussing on primary CH and isolated CCH.

Efficient Industrial Synthesis of the MDM2 Antagonist Idasanutlin via a Cu(I)-catalyzed [3+2] Asymmetric Cycloaddition

A concise asymmetric synthesis has been developed to prepare idasanutlin, a small molecule MDM2 antagonist. Idasanutlin is currently being investigated as a potential treatment for various solid tumors and hematologic malignancies. The highly congested pyrrolidine core, containing four contiguous stereocenters, was constructed via a Cu(I)/(R)-BINAP catalyzed [3+2]-cycloaddition reaction. This optimized copper(<small>I</small>)-catalyzed process has been used to produce more than 1500 kg of idasanutlin. The manufacturing process will be described, highlighting the exceptionally selective and consistent cycloaddition/isomerization/hydrolysis sequence. The excellent yields, short cycle times and reduction in waste streams result in a sustainable production process with low environmental impact.

Diagnosis and severity criteria for sinusoidal obstruction syndrome/veno-occlusive disease in pediatric patients: a new classification from the European society for blood and marrow transplantation

The advances in hematopoietic cell transplantation (HCT) over the last decade have led to a transplant-related mortality below 15%. Hepatic sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a life-threatening complication of HCT that belongs to a group of diseases increasingly identified as transplant-related, systemic endothelial diseases. In most cases, SOS/VOD resolves within weeks; however, severe SOS/VOD results in multi-organ dysfunction/failure with a mortality rate >80%. A timely diagnosis of SOS/VOD is of critical importance, given the availability of therapeutic options with favorable tolerability. Current diagnostic criteria are used for adults and children. However, over the last decade it has become clear that SOS/VOD is significantly different between the age groups in terms of incidence, genetic predisposition, clinical presentation, prevention, treatment and outcome. Improved understanding of SOS/VOD and the availability of effective treatment questions the use of the Baltimore and Seattle criteria for diagnosing SOS/VOD in children. The aim of this position paper is to propose new diagnostic and severity criteria for SOS/VOD in children on behalf of the European Society for Blood and Marrow Transplantation.

Prognostic value of the circumferential resection margin and its definitions in esophageal cancer patients after neoadjuvant chemoradiotherapy

The accepted importance of a positive circumferential resection margin (CRM) (defined as R1 in the TNM classification) is based on histopathology of the resection specimen obtained after primary surgery in esophageal cancer patients. The aim of this study is to look for the prognostic value of CRM after neoadjuvant chemoradiotherapy and to compare the clinical significance of a histologically CRM < 1 mm from the cut margin (Royal College of Pathologists definition of R1) to a positive cut margin (College of American Pathologists definition of R1) and to ≥1 mm margin (R0) resections in patients with ypT3-esophageal tumors after neoadjuvant chemoradiotherapy. Between 2000 and 2014, 458 patients who received esophagectomy after neoadjuvant chemoradiation therapy were selected. Overall (OS) and disease-free survival (DFS) were calculated by means of Kaplan-Meier curves and compared by Cox regression analysis. There were 163 (35.9%) patients who had a ypT3 tumor; in 118 (72.4%) resection was complete (R0). In 37 (22.7%) patients a CRM < 1 mm was found and 8 (4.9%) had a circumferential R1-resection. CRM involvement was inversely correlated with tumor regression grading, lymph node capsular involvement, and number of positive lymph nodes. On univariate analysis, no statistically significant difference was found between R0-resection and CRM < 1 mm (P = 0.103) for OS, but DFS showed a significant difference (P = 0.025). Circumferential R1-resections showed a significant difference compared to R0-resections for OS and DFS (both P = 0.002). In multivariate analysis, extracapsular lymph node involvement and circumferential R1-resection were withheld as independent prognosticators for OS, whereas extracapsular lymph node involvement, absence of regression on the primary tumor and circumferential R1-resection were withheld for DFS. After correcting for different variables in the multivariate model, CRM < 1 mm showed no statistical difference compared to R0-resections neither for OS nor for DFS. After neoadjuvant chemoradiotherapy, CRM is correlated with biological behavior of the tumor and with therapy response. Furthermore it is an independent prognosticator for OS and DFS. However CRM < 1 mm itself is no independent prognosticator for OS nor DFS survival in multivariable analysis. These results suggest that the definition of R1-resection should be limited to true invasion of the section plane.