Age-specific nasal epithelial responses to SARS-CoV-2 infection

Children infected with SARS-CoV-2 rarely progress to respiratory failure. However, the risk of mortality in infected people over 85 years of age remains high. Here we investigate differences in the cellular landscape and function of paediatric (<12 years), adult (30-50 years) and older adult (>70 years) ex vivo cultured nasal epithelial cells in response to infection with SARS-CoV-2. We show that cell tropism of SARS-CoV-2, and expression of ACE2 and TMPRSS2 in nasal epithelial cell subtypes, differ between age groups. While ciliated cells are viral replication centres across all age groups, a distinct goblet inflammatory subtype emerges in infected paediatric cultures and shows high expression of interferon-stimulated genes and incomplete viral replication. In contrast, older adult cultures infected with SARS-CoV-2 show a proportional increase in basaloid-like cells, which facilitate viral spread and are associated with altered epithelial repair pathways. We confirm age-specific induction of these cell types by integrating data from in vivo COVID-19 studies and validate that our in vitro model recapitulates early epithelial responses to SARS-CoV-2 infection.

[Bond strength of metal brackets to enamel with a Russian adhesive complex: an in vitro study]

BACKGROUND

The era of using adhesives to fix brackets began in the 70s of the last century. There are eight generations of foreign-made adhesive systems for the restoration of teeth. However, until now, in orthodontics, the development of domestic adhesive systems with improved properties of adhesion of brackets to tooth enamel still important, especially in the posterior teeth.

OBJECTIVE

The purpose of this work was to study the shear strength of fifth generation domestic adhesive between metal brackets and the enamel of molar teeth in laboratory conditions.

MATERIAL AND METHODS

The study included 17 specimens of extracted maxillary molars embedded in acrylic resin blocks. Brackets from G&H Orthodontics (G&H Wire Company, USA) were fixed to the tooth enamel using the domestic Compofix (ortho) set. The enamel was treated with etching gel (37% phosphoric acid) for 30 seconds. Then the gel was washed off with water and the surface of the enamel was thoroughly dried. A primer was applied to the prepared surface with an applicator, inflated with a weak air flow for 5-10 seconds and photopolymerized for 20 seconds. The surface of the bracket was treated with degreaser, then a thin layer of adhesive was applied, and the sample was fixed to the enamel. Excess material was removed with an applicator. The samples were photopolymerized for 20 sec. Then, the shear bond strength of the adhesive was determined according to the method of GOST 31574-2012 on a (Zwick/Roell Z010 testing machine, Zwick, Germany).

RESULTS

The shear strength of the adhesive joint obtained during the test is 13.54±1.01 MPa, the average value of the index of adhesive residues on the surface of the bracket was 23%±4%, which corresponds to the standard average values according to GOST.

CONCLUSION

The tested domestic adhesive system of the fifth generation can be recommended for the practical work of an orthodontist.

Unravelling the antibacterial potential of biosynthesized selenium nanoparticles against Salmonella Typhimurium food pathogen: in vitro and in vivo investigation

OBJECTIVE

It is highly required to find novel alternatives to the antibiotics currently used due to the increasing dissemination of antibiotic resistance among bacteria, especially enteric bacteria. The current study aimed to produce selenium nanoparticles (SeNPs) by Euphorbia milii Des Moul leaves extract (EME).

MATERIALS AND METHODS

The produced SeNPs were characterized using different techniques. After that, in vitro and in vivo antibacterial activity against Salmonella typhimurium was elucidated. Moreover, phytochemical identification and quantification of the chemical compositions of EME were performed using HPLC. The broth microdilution method determined the minimum inhibitory concentrations (MICs).

RESULTS

The MIC values of SeNPs ranged from 128 to 512 µg/mL. Additionally, the impact of SeNPs on membrane integrity and permeability was investigated. A marked decline in the membrane integrity and inner and outer membrane permeability was noticed in 50%, 46.15%, and 50% of the tested bacteria, respectively. Subsequently, a gastrointestinal tract infection model was used to study the in vivo antibacterial potential of SeNPs. Remarkably, treatment with SeNPs resulted in average-sized intestinal villi and colonic mucosa in the small intestine and caecum, respectively. In addition, it was revealed there was no inflammation or dysplasia in the studied tissues. SeNPs also enhanced the survival rate and significantly decreased the number of colony-forming units per gram tissues in the small intestine and caecum. Concerning the inflammatory markers, SeNPs significantly (p < 0.05) decreased interleukins (6 and 1β).

CONCLUSIONS

The biosynthesized SeNPs revealed antibacterial potential in vivo and in vitro; however, this finding should be elucidated clinically in the future.

265 A PHYSIOTHERAPY-LED TRANSITION TO HOME INTERVENTION FOR OLDER ADULTS FOLLOWING EMERGENCY DEPARTMENT DISCHARGE: A PILOT FEASIBILITY RANDOMISED-CONTROLLED TRIAL

Background

Older adults frequently attend the Emergency Department (ED) and experience high rates of adverse outcomes following ED presentation including functional decline, ED re-presentation and unplanned hospital admission. The development of effective interventions to prevent such outcomes is a key priority for research and service provision. A presentation to an ED can be viewed as an opportunity to assess those at risk of adverse outcomes and initiate a care plan in those deemed as ‘high risk'. Our aim was to evaluate the feasibility of a physiotherapy led integrated care intervention for older adults discharged from the ED (ED-PLUS).

Methods

Older adults presenting to the ED with undifferentiated medical complaints and discharged within 72 hours were computer randomised in a ratio of 1:1:1 to deliver usual care, Comprehensive Geriatric Assessment (CGA) in the ED, or ED-PLUS (Trial registration: NCT04983602). ED-PLUS is an evidence-based and stakeholder-informed intervention to bridge the care transition between the ED and community by initiating a CGA in the ED and implementing a six-week, multi-component, self-management programme in the patient’s own home. Feasibility (recruitment and retention rates) and acceptability of the programme were assessed quantitatively and qualitatively. Functional decline was examined post-intervention using the Barthel Index. All outcomes were assessed by a research nurse blinded to group allocation.

Results

29 participants were recruited, indicating 97% of our recruitment target. 90% of participants completed the ED-PLUS intervention. All participants expressed positive feedback about the intervention. The incidence of functional decline at 6 weeks was 10% in the ED-PLUS group versus 70-89% in the usual care and CGA-only groups.

Conclusion

High adherence and retention rates were observed among participants and preliminary findings indicate a lower incidence of functional decline in the ED-PLUS group. Recruitment challenges existed in the context of COVID-19. Data collection is ongoing for six-month outcomes.

Local and systemic responses to SARS-CoV-2 infection in children and adults

It is not fully understood why COVID-19 is typically milder in children1-3. Here, to examine the differences between children and adults in their response to SARS-CoV-2 infection, we analysed paediatric and adult patients with COVID-19 as well as healthy control individuals (total n = 93) using single-cell multi-omic profiling of matched nasal, tracheal, bronchial and blood samples. In the airways of healthy paediatric individuals, we observed cells that were already in an interferon-activated state, which after SARS-CoV-2 infection was further induced especially in airway immune cells. We postulate that higher paediatric innate interferon responses restrict viral replication and disease progression. The systemic response in children was characterized by increases in naive lymphocytes and a depletion of natural killer cells, whereas, in adults, cytotoxic T cells and interferon-stimulated subpopulations were significantly increased. We provide evidence that dendritic cells initiate interferon signalling in early infection, and identify epithelial cell states associated with COVID-19 and age. Our matching nasal and blood data show a strong interferon response in the airways with the induction of systemic interferon-stimulated populations, which were substantially reduced in paediatric patients. Together, we provide several mechanisms that explain the milder clinical syndrome observed in children.

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.

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.

Post-coronavirus disease 2019 polyneuropathy with significant response to immunoglobulin therapy: a case report

Background

The symptoms of coronavirus disease 2019, caused by the novel severe acute respiratory syndrome coronavirus 2, were originally assumed to be mainly respiratory. With increasing knowledge, however, it turned out that the spectrum of complaints varies broadly with age and concomitant diseases. While many neurological symptoms were reported in the context of the disease, ranging from permanent fatigue to recurrent headaches and concentration disturbance, treatment approaches are still in development. This case discusses a possible treatment approach with immunoglobulin therapy and its outcomes.

Case presentation

We present the case of a 56-year-old Caucasian female patient who, following coronavirus disease 2019, developed peripheral sensory and autonomic disturbances that fell within subacute demyelinating neuropathy. Because a significant improvement in symptoms as well as in the results of clinical and electrophysiological examination was reported after immunoglobulin therapy, long-term therapy does not appear to be necessary.

Conclusion

Given the significant subjective and objective improvement reported, this case provides additional evidence that immunoglobulin therapy can be considered in post-coronavirus disease 2019 syndrome.

Performance evaluation of a Compression Ignition Engine using Sand Apple (Parinari polyandra B.) ethyl ester (biodiesel)

The quest for non-edible oil for the production of alternative fuel (bio-fuel) using homogeneous catalysts continues to supplement and replace in totality the traditional transportation fuels that are not environmentally friendly. The use of biodiesel in Compression Ignition Engines (CIE) to evaluate the engine performance is a norm and blends of biodiesel and Automotive Gas Oil (AGO) are also used in the engine performance processes to ascertain its usage in the CIE. Therefore, this study evaluated the performance of a compression-ignition engine (CIE) fuelled with biodiesel produced from sand apple oil using eggshell as a heterogeneous catalyst. Transesterification of Sand Apple Oil (SAO) with ethanol to produce ethyl ester and glycerol was optimized. Sand Apple Ethyl Esters (SAEE) was blended with Automotive Gas Oil (AGO) at 5 – 25% mix to evaluate the performance of a 3.68 kW diesel engine at five loading conditions (0, 25. 50, 75, 100%). Performance tests were carried out to determine torque, speed, exhaust gas temperature and fuel consumption rate. Data obtained were analyzed using ANOVA at P < 0.05 significant level. Results of parameters tested ranged from 6.50 – 6.60 Nm, 2795 – 2950 rpm, 385 – 400 °C and 2.93 – 5.00 × 10−6 kg/s, respectively for all the blends. The study established that the performance of the diesel engine using 5 – 25% SAEE-AGO blends was similar to using AGO alone and SAEE is therefore suitable for use in the CIE.

941 Post-Operative Outcomes of Patients Undergoing Surgery During the Acceleration Period of COVID-19 Infection

Introduction

There are concerns around the safety of performing surgery during COVID-19 outbreaks with few sources of robust evidence.

Method

We analysed 5020 consecutive patients who underwent surgery during the acceleration phase of COVID-19 at our hospital from 31st January to 13th April 2020. Data were also analysed for all patients who had a COVID-19 positive test result during the same study period.

Results

156 patients (3%) developed COVID-19 symptoms after surgery; 28 patients (<1%) subsequently had a positive swab result. All-cause mortality was 44 patients (0.9%); 33 deaths (75%) were due to non COVID-19 diagnoses. There were no adverse COVID-19 related outcomes in any of the 648 patients who had cancer operations. Of 28 COVID-19 positive patients, 11 died (8 orthopaedic, 2 urology, 1 vascular surgery) of which 10 had an emergency admission; all were over 70 years of age. Recent surgery was not an independent prognostic factor for survival after COVID-19 infection. 12% of positive COVID-19 swabs were from long-stay patients.

Conclusions

Of 5020 operative patients, 0.2% died from COVID-19 and most complications were not related to the infection. With careful consideration, surgery can be provided safely during times of COVID-19 outbreaks with particular emphasis on avoiding in-hospital transmission.

Single-cell multi-omics analysis of the immune response in COVID-19

Analysis of human blood immune cells provides insights into the coordinated response to viral infections such as severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). We performed single-cell transcriptome, surface proteome and T and B lymphocyte antigen receptor analyses of over 780,000 peripheral blood mononuclear cells from a cross-sectional cohort of 130 patients with varying severities of COVID-19. We identified expansion of nonclassical monocytes expressing complement transcripts (CD16+C1QA/B/C+) that sequester platelets and were predicted to replenish the alveolar macrophage pool in COVID-19. Early, uncommitted CD34+ hematopoietic stem/progenitor cells were primed toward megakaryopoiesis, accompanied by expanded megakaryocyte-committed progenitors and increased platelet activation. Clonally expanded CD8+ T cells and an increased ratio of CD8+ effector T cells to effector memory T cells characterized severe disease, while circulating follicular helper T cells accompanied mild disease. We observed a relative loss of IgA2 in symptomatic disease despite an overall expansion of plasmablasts and plasma cells. Our study highlights the coordinated immune response that contributes to COVID-19 pathogenesis and reveals discrete cellular components that can be targeted for therapy.

Umbilical Cord Prolapse in the Prehospital Setting: A Case Report

Umbilical cord prolapse is an acute obstetric emergency associated with high fetal morbidity and mortality. To avoid poor outcomes, rapid diagnosis with immediate intervention is required, especially in the prehospital setting where resources are limited. In this case report, we describe a 38-year-old woman with umbilical cord prolapse, with a review of appropriate prehospital maneuvers and treatment.

Adjustment disorder with anxiety in old age: Comparing prevalence and clinical management in primary care and mental health care

Purpose:

Adjustment disorder with anxiety (AjD-A) is a common cause of severe anxiety symptoms, but little is known about its prevalence in old age.

Methods:

This cross-sectional study examined the prevalence of AjD-A in outpatients over the age of 60 who consecutively consulted 34 general practitioners and 22 psychiatrists during a 2-week period. The diagnosis of AjD-A was obtained using the optional module for diagnostic of adjustment disorder of the Mini International Neuropsychiatric Interview (MINI). The study procedure also explored comorbid psychiatric conditions and documented recent past stressful life events, as well as social disability and current pharmacological and non-pharmacological management.

Results:

Overall, 3651 consecutive subjects were screened (2937 in primary care and 714 in mental health care). The prevalence rate of AjD-A was 3.7% (n = 136). Up to 39% (n = 53) of AjD-A subjects had a comorbid psychiatric condition, mostly of the anxious type. The most frequently stressful life event reported to be associated with the onset of AjD-A was personal illness or health problem (29%). More than 50% of the AjD-A patients were markedly to extremely disabled by their symptoms. Compared to patients who consulted psychiatrists, patients who were seen by primary care physicians were older, had obtained lower scores at the Hamilton Anxiety Rating Scale, benefited less frequently from non-pharmacological management and received benzodiazepines more frequently.

Conclusions:

AjD-A appears to be a significantly disabling cause of anxiety symptoms in community dwelling elderly persons, in particular those presenting personal health related problems. Improvement of early diagnosis and non-pharmacological management of AjD-A would contribute to limit risks of benzodiazepine overuse, particularly in primary care settings.

Understanding the effects of pasture type and stocking rate on the hydrology of the Southern Great Plains

Grassland is one of the major biomes in the United States (US) and the world. In the US, the majority of grasslands are concentrated in the Great Plains and has undergone through significant interventions or management changes over the last few decades. A key economy-driven intervention in the Southern Great Plains (SGP) include the introduction of new forage species and conversion of native grassland to introduced pasture to increase productivity and its nutritive value for improved cattle production. Since water is one of the fundamental resources needed to sustain grassland productivity, it is important to understand how such pasture conversion and prevailing cattle grazing practices affect water balance and biomass production in a given pasture system. In this study, the Nutrient Tracking Tool (NTT) with its core APEX (Agricultural Policy Environmental eXtender) model was used to assess the hydrological impacts of the pasture introduction, i.e., native pasture (little bluestem, Schizachyrium halapense) vs. introduced pasture (old world bluestem, Bothriochloa caucasica), and the stocking rate in the SGP. Monthly evapotranspiration (ET) and biomass estimates from NTT compared well with observed data at two USDA-ARS experimental pastures (native and introduced) near El Reno, Oklahoma, for the years 2015 and 2016. Simulated long-term average annual hydrologic fluxes (i.e., ET, runoff, and groundwater recharge) from the introduced pasture were slightly lower than the observed data but not significantly different than those from the native pasture under the current management conditions. NTT predicted higher water yield (runoff and recharge) and significantly lower ET for the introduced pasture than the native pasture. Results suggest that grazing has the potential to alter the hydrological balance in the SGP. For example, the increase in stocking rate within the carrying capacity of the farm decreases ET and increases runoff and groundwater recharge for both pastures. Comparison of estimated biomass production between native and introduced pastures indicated that introduced pastures are more efficient in using the available water and thus produce a higher forage biomass per unit of water in the SGP. This study highlighted the potential significance of considering hydrological and other biophysical impacts of new forage introduction and stocking rate changes for the sustainable management of grazing and pasture systems in the SGP.

Comparison of five methods for detection of carbapenemases in Enterobacterales with proposal of a new algorithm

OBJECTIVES

The aim of this study was to evaluate the performance of five different carbapenemase tests and to develop an algorithm which will permit the detection of most common and rare carbapenemases in routine microbiology laboratories.

METHODS

The immunochromatographic tests CARBA-5 (NG), RESIST-4 O.K.N.V. (Coris), the colorimetric β-CARBA (BioRad), a newly developed carbapenem-inactivation method (CIM) supplemented with zinc (zCIM), and the Xpert Carba-R (Cepheid) were challenged with a collection of 189 molecularly characterized Enterobacterales isolates, including 146 carbapenemase producers (CPE): VIM (n = 48), OXA-48-like (n = 40), NDM (n = 29), KPC (n = 13), IMI (n = 9), IMP (n = 9), OXA-58 (n = 2), and GES (n = 2).

RESULTS

The overall sensitivity/specificity values for the five carbapenemase detection tests were 84.2% (CI 77.6-89.2%)/100% (CI 91.8-100%) for RESIST-4, 88.2% (CI 82.1-92.4%)/100% (CI 91.8-100%) for CARBA-5, 88.2% (CI 82.1-92.4%)/100% (CI 91.8-100%) for Xpert Carba-R, 73.7% (CI 66.2-80.0%)/100% (CI 93.4-99.0%) for β-CARBA, and 97.4% (CI 87.9-99.6%)/97.7% (CI 87.9-99.6%) for zCIM. The four common carbapenemases (KPC, OXA-48-like, NDM, and VIM) were detected with ≥97.6% sensitivity by all tests except for β-CARBA (76.6% (CI 68.4-83.2%)). IMI and GES were only detected by zCIM (sensitivity 90.9% (CI 62.3-98.4%)). Based on these results a new algorithm was developed, consisting of an immunochromatographic assay as the first test followed by zCIM, which allows detection of 99.3% of all carbapenemases assessed.

CONCLUSIONS

Except for β-CARBA, all methods showed excellent sensitivity/specificity for the detection of the four most frequent carbapenemases. With the new algorithm, rare variants can also be detected. It is rapid, simple, and inexpensive and can be performed in any microbiology laboratory, as no PCR equipment is required.

159 Effect of bisphenol A and bisphenol S on AMH and AMHR mRNA expression during in vitro bovine oocyte maturation and early embryo development

Exposure to chemicals with known endocrine-disrupting effects, such as bisphenol A (BPA) and bisphenol S (BPS), leads to repercussions on oocyte development and, ultimately, on fertility. Bisphenol A is a plasticizer used worldwide that has been detected in blood, urine, tissue samples and follicular fluid. Due to its widely reported detrimental effects, BPA has been substituted with its analogue BPS. Previous experiments in our laboratory have shown that exposure of bovine oocytes to physiologically relevant doses of BPA resulted in spindle abnormalities, reduced meiosis progression, decreased blastocyst rate and gene expression changes. However, the effects of BPS have not yet been investigated. Anti-Müllerian hormone (AMH) has been reported to be a good marker of ovarian reserve and oocyte developmental capability and is commonly used in assisted reproduction for diagnostic measurements. There is evidence that women undergoing IVF with higher BPA levels have lower AMH levels and pregnancy success. The aim of this study was to assess the effect of BPA and BPS on AMH and its receptor as measures of oocyte developmental capability. Abattoir-derived bovine cumulus-oocyte complexes (COC) were matured in vitro in 4 groups: (1) control, (2) vehicle (0.1% ethanol), (3) BPA (0.05mg mL−1 in 0.1% ethanol), and (4) BPS (0.05mg mL−1 in 0.1% ethanol). Pools of 30 COC, 30 denuded oocytes, and cumulus cells corresponding to denuded oocytes were collected for each of the 4 experimental groups, and a minimum of 4 biological replicates were used for each analysis. Anti-Müllerian hormone and AMH receptor mRNA expression was measured in COC, denuded oocytes, and their corresponding cumulus cells using quantitative real-time PCR. Statistical analyses were performed using 1-way ANOVA. Results showed a decrease (P&lt;0.05) in AMH mRNA expression in BPA-treated oocytes (without cumulus cells). In addition, there was an increase (P&lt;0.05) in mRNA AMH receptor levels in COC when treated with BPS. Finally, analyses on cumulus cells alone showed an increase (P&lt;0.05) in the AMH receptor mRNA levels in BPA-treated cells. These results suggest that BPA has an effect on AMH mRNA transcript levels in oocytes, while affecting the receptor expression in cumulus cells. Conversely, BPS affects AMH indirectly, increasing the mRNA levels of its receptor only. Further investigation of the effects of BPA and BPS on AMH expression in in vitro-produced blastocysts derived from treated oocytes will aid in understanding the potential consequences of exposure to BPA and its analogues on early embryonic development.

A systematic review of meta-analyses in orthopaedic surgery between 2000 and 2016

AIMS

The aims of this systematic review were to describe the quantity and methodological quality of meta-analyses in orthopaedic surgery published during the last 17 years.

MATERIALS AND METHODS

MEDLINE, EMBASE, and PubMed, between 1 January 2000 and 31 December 2016, were searched for meta-analyses in orthopaedic surgery dealing with at least one surgical intervention. Meta-analyses were included if the interventions involved a human muscle, ligament, bone or joint.

RESULTS

A total of 392 meta-analyses met eligibility criteria, for which the mean AMSTAR quality score was 7.1/11. There was a positive correlation between the year of publication and the quality of the meta-analysis (r = 0.238, p < 0.001). Between 2000 and 2011, the mean AMSTAR score corresponded to that of a medium quality review. However, between 2012 and 2016, the mean scores have been consistently equivalent to those of a high-quality review. The number of meta-analyses published increased 10-fold between 2005 and 2014.

CONCLUSION

The quantity and quality of meta-analyses in orthopaedic surgery which have been published has increased, reaching a plateau in 2012. Methodological flaws remain to be addressed in future meta-analyses in order to continue increasing the quality of the orthopaedic literature. Cite this article: Bone Joint J 2018;100-B:1270-4.

Abstract 2051: Perfusable 3D angiogenesis in a high-throughput microfluidic culture platform

The transition from 2D to 3D cell culture is a first step towards more physiologically relevant in vitro cancer models. To adequately capture the complex tissue architectures observed in vivo, 3D microfluidic techniques incorporate and achieve long-term gradient stability, continuous perfusion and patterning of cancer cell layers as stratified co-cultures. We used a standardized high-throughput (n=40) microfluidic 3D tissue culture platform called the OrganoPlate® to generate precisely controlled gradients, without pumps, ideal for growing blood vessels and inducing controlled 3D angiogenic sprouting. The blood vessel is grown against an extracellular matrix (ECM) gel with cancer cells and is subsequently exposed to pro- and antiangiogenic compounds to direct sprouting towards 3D cancer cell clusters. Utilizing high-content confocal time-lapse imaging and analysis, angiogenic potential was measured in various cancer models. The exposed vasculature shows many of the important hallmarks of cancer angiogenesis found in vivo, including tip cells induction and migration and stalk cells formation. Importantly, the stalk cells develop a perfusable lumen that is connected to the parental vessel as demonstrated with perfusion of high-molecular-weight (150KD) fitc-dextran through microvascular structures. This model will be used as an in vitro cancer screening platform to unravel the important drivers in angiogenesis and vasculogenesis and the mechanism of action of antiangiogenic compounds. By combining this culture platform with mural cells, cell-cell interactions can be studied. In parallel, we will combine this 3D cancer angiogenesis platform with our current Tumor-on-a-Chip models to create tissue models with integrated vasculature.

Citation Format: K M. Bircsak, V van Duinen, S J. Trietsch, A J. van Zonneveld, T Hankemeier, A Saleh, P Vulto. Perfusable 3D angiogenesis in a high-throughput microfluidic culture platform [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2051.

Percutaneous Closure of Left Atrial Appendage significantly affects Lipidome Metabolism

Patients with non-valvular atrial fibrillation (AF) and a high risk for oral anticoagulation can be treated by percutaneous implantation of left atrial appendage occlusion devices (LAAC) to reduce the risk of cardio-embolic stroke. This study evaluates whether LAAC may influence lipid metabolism, which has never been investigated before. Patients with successful LAAC were included consecutively. Venous peripheral blood samples of patients were collected immediately before (T0, baseline) and 6 months after (T1, mid-term) LAAC. A targeted metabolomics approach based on electrospray ionization liquid chromatography-mass spectrometry (ESI-LC-MS/MS) and MS/MS measurements was performed. A total of 34 lipids revealed a significant change from baseline to mid-term follow-up after successful LAAC. Subgroup analysis revealed confounding influence by gender, age, diabetes mellitus type II, body mass index, left ventricular ejection fraction, creatinine and NT-proBNP. After multivariable adjustment within logistic regression models, these 34 lipids were still significantly altered after LAAC. Successful percutaneous LAAC may affect lipid metabolism and thereby may potentially affect pro-atherogenic and cardio-toxic effects.

Serum biomarkers in periprosthetic joint infections

OBJECTIVES

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

METHODS

We searched two literature databases, using terms that encompass all hip and knee arthroplasty procedures, as well as PJI and statistical terms reflecting diagnostic parameters. The findings are summarized as a narrative review.

RESULTS

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were the two most commonly published serum biomarkers. Most evidence did not identify other serum biomarkers that are clearly superior to ESR and CRP. Other serum biomarkers have not demonstrated superior sensitivity and have failed to replace CRP and ESR as first-line screening tests. D-dimer appears to be a promising biomarker, but more research is necessary. Factors that influence serum biomarkers include temporal trends, stage of revision, and implant-related factors (metallosis).

CONCLUSION

Our review helped to identify factors that can influence serum biomarkers' level changes; the recognition of such factors can help improve their diagnostic utility. As such, we cannot rely on ESR and CRP alone for the diagnosis of PJI prior to second-stage reimplantation, or in metal-on-metal or corrosion cases. The future of serum biomarkers will likely shift towards using genomics and proteomics to identify proteins transcribed via messenger RNA in response to infection and sepsis.Cite this article:Bone Joint Res 2018;7:85-93.

Comparison of adjunctive azithromycin and amoxicillin/metronidazole for patients with chronic periodontitis: preliminary randomized control trial

BACKGROUND

There are insufficient guidelines for the use of adjunctive systemic antibiotics for patients with periodontal disease. The aim of this study was to compare clinical outcomes for patients with moderate-advanced chronic periodontitis treated with: scaling and root planing (SRP), SRP with amoxicillin and metronidazole (A+M), SRP with Azithromycin (Az).

METHODS

Thirty-seven non-smokers with generalized moderate to advanced chronic periodontitis were divided into three treatment groups: SRP, A+M and Az. Patients received the medications after the last SRP session and were reviewed three months later. Changes in clinical parameters were compared between the groups. Separate analyses were executed for: 'all sites', 'molar sites', 'sites with different PPD severities' and 'number of sites with shallow, moderate and deep PPD'.

RESULTS

The three groups exhibited improvements in most clinical parameters. At three months, A+M showed a higher reduction in PPD compared to Az in the 'all sites analysis'. Molars exhibited better reduction in BOP and PPD with A+M than SRP. Pocket depth of the 4-6 mm category reduced more in the A+M than SRP. A+M experienced a higher increase in the number of sites with PPD 1-3 mm than Az.

CONCLUSIONS

Adjunctive systemic antibiotics in the initial phase of treatment may result in improved clinical outcomes.

Impact of portal vein infiltration and type of venous reconstruction in surgery for borderline resectable pancreatic cancer

BACKGROUND

The International Study Group of Pancreatic Surgery (ISGPS) recommends operative exploration and resection of pancreatic cancers in the presence of reconstructable mesentericoportal axis involvement. However, there is no consensus on the ideal method of vascular reconstruction. The effect of depth of tumour invasion of the vessel wall on outcome is also unknown.

METHODS

This was a retrospective cohort study of pancreaticoduodenectomy with vein resection for T3 adenocarcinoma of the head of the pancreas across nine centres. Outcome measures were overall survival based on the impact of the depth of tumour infiltration of the vessel wall, and morbidity, in-hospital mortality and overall survival between types of venous reconstruction: primary closure, end-to-end anastomosis and interposition graft.

RESULTS

A total of 229 patients underwent portal vein resection; 129 (56·3 per cent) underwent primary closure, 64 (27·9 per cent) had an end-to-end anastomosis and 36 (15·7 per cent) an interposition graft. There was no difference in overall morbidity (26 (20·2 per cent), 14 (22 per cent) and 9 (25 per cent) respectively; P = 0·817) or in-hospital mortality (6 (4·7 per cent), 2 (3 per cent) and 2 (6 per cent); P = 0·826) between the three groups. One hundred and six patients (47·5 per cent) had histological evidence of vein involvement; 59 (26·5 per cent) had superficial invasion (tunica adventitia) and 47 (21·1 per cent) had deep invasion (tunica media or intima). Median survival was 18·8 months for patients who had primary closure, 27·6 months for those with an end-to-end anastomosis and 13·0 months among patients with an interposition graft. There was no significant difference in median survival between patients with superficial, deep or no histological vein involvement (20·8, 21·3 and 13·3 months respectively; P = 0·111). Venous tumour infiltration was not associated with decreased overall survival on multivariable analysis.

CONCLUSION

In this study, there was no difference in morbidity between the three modes of venous reconstruction, and overall survival was similar regardless of tumour infiltration of the vein.

A case study of likely wild-type cardiac transthyretin amyloidosis causing rapid deterioration

We present the case of an 88-year-old gentleman who presented to hospital septic with bilateral leg cellulitis, pulmonary oedema and hypotension. He had no history of heart disease but had had bilateral carpal tunnel releases. His condition deteriorated with refractory hypotension in spite of fluid filling, inotropic and vasopressor support. His echocardiogram showed an infiltrative cardiomyopathy with a speckled myocardium, severe concentric left and right ventricular increased wall thickness, diastolic dysfunction, biatrial dilatation and restrictive physiology in keeping with cardiac amyloidosis. He developed atrial fibrillation and worsening respiratory failure due to fluid overload and was intubated and ventilated but continued to decline and passed away. The degree of heart failure in the absence of ischaemia, the patient's advanced age, echocardiographic findings and past history of carpal tunnel syndrome in a male are strongly indicative of a diagnosis of wild-type cardiac transthyretin amyloidosis. We discuss the key features and intensive care management of this disease.

Validation and development of MTH1 inhibitors for treatment of cancer

BACKGROUND

Previously, we showed cancer cells rely on the MTH1 protein to prevent incorporation of otherwise deadly oxidised nucleotides into DNA and we developed MTH1 inhibitors which selectively kill cancer cells. Recently, several new and potent inhibitors of MTH1 were demonstrated to be non-toxic to cancer cells, challenging the utility of MTH1 inhibition as a target for cancer treatment.

MATERIAL AND METHODS

Human cancer cell lines were exposed in vitro to MTH1 inhibitors or depleted of MTH1 by siRNA or shRNA. 8-oxodG was measured by immunostaining and modified comet assay. Thermal Proteome profiling, proteomics, cellular thermal shift assays, kinase and CEREP panel were used for target engagement, mode of action and selectivity investigations of MTH1 inhibitors. Effect of MTH1 inhibition on tumour growth was explored in BRAF V600E-mutated malignant melanoma patient derived xenograft and human colon cancer SW480 and HCT116 xenograft models.

RESULTS

Here, we demonstrate that recently described MTH1 inhibitors, which fail to kill cancer cells, also fail to introduce the toxic oxidized nucleotides into DNA. We also describe a new MTH1 inhibitor TH1579, (Karonudib), an analogue of TH588, which is a potent, selective MTH1 inhibitor with good oral availability and demonstrates excellent pharmacokinetic and anti-cancer properties in vivo.

CONCLUSION

We demonstrate that in order to kill cancer cells MTH1 inhibitors must also introduce oxidized nucleotides into DNA. Furthermore, we describe TH1579 as a best-in-class MTH1 inhibitor, which we expect to be useful in order to further validate the MTH1 inhibitor concept.

Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170  TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.

Medical undergraduates' contributions to publication output of world's top universities in 2013

BACKGROUND

Medical undergraduates' (UGs) involvement in research activities is thought to be mutually beneficial to students, their mentors and the scholarly productivity of their universities. However, most evidence in favor of such assumption relies on subjective measures such as the self-reported gains in skills or knowledge rather than robust objective estimates for assessing impact.

AIM

We aimed to objectively track and describe publications with UG co-authors-their proportion to the total publication output of world's top universities, their characteristics and their potential impact on biomedical literature.

METHODS

We contacted the corresponding authors of the 2013's Medline-indexed publications affiliated to world's top 10 universities to investigate if any of their co-authors was an UG. Articles with UG co-authors were further assessed to determine, along with other variables: the type of study design, field of the article, publishing journal and its impact factor (IF), and number of received citations.

RESULTS

Out of 25 152 publications, 2537 articles (10.1%) contained at least one UG co-author who was the first author in 635 papers (25%). Articles with UG co-authors were published in 1114 journals with a median IF of 3.661. Most UGs' co-authored publications (82.7%, n = 2098) were cited at least once within 1 year, for a median of three citations per article.

CONCLUSION

UGs contributed to one in every 10 publications affiliated to top universities. Their papers were published in journals with good IFs and received a fair number of citations, which would reflect the relatively good quality and impact of these articles.

Early postoperative tissue harmonic sonography of the thyroid gland

Purpose: Fundamental gray-scale imaging (FGI) is known to be unuseful for thyroid imaging in the early postoperative setting. Thus, we evaluated the feasability of tissue harmonic imaging (THI) early after thyroid resection.

Material and Methods: FGI and THI of the neck were perfomed in 48 consecutive patients 4 days after surgery. The examiner was blinded to patient diagnoses and types of surgery. FGI and THI examinations were stored on videotape and reviewed offline by two different readers who rated the quality of delineation of the organ borders and presence or absence of focal lesions. The results were compared to neck US performed 12 weeks after surgery.

Results: Delineation of the thyroid remnants in THI/FGI was rated to be excellent in 22/2, good in 11/9, poor in 3/16 and not visible at all in 4/13 patients. The correlation between THI-volumetry and control-volumetry was very high (r=0.81; p&lt;0.0001). THI but not FGI depicted presence or absence of solid thyroid nodules with 100% accuracy.

Conclusion: THI is a feasible method for thyroid US in the early postoperative setting. It permits volumetry of the residual thyroid tissue and accurately depicts nodules within the thyroid remnant.

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst)  MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.

Outcome after pancreaticoduodenectomy for T3 adenocarcinoma: A multivariable analysis from the UK Vascular Resection for Pancreatic Cancer Study Group

BACKGROUND

Most resectable pancreatic cancers are classified as T3, including those involving the porto-mesenteric vein. Survival and perioperative morbidity for venous resection have been found to be comparable to standard resection. We investigate factors associated with short and long term outcomes in pancreaticoduodenectomy with (PDVR) and without (PD) venous resection exclusively for T3 adenocarcinoma of the head of the pancreas.

METHODS

This is a UK multicenter retrospective cohort study assessing outcomes in patients undergoing PD and PDVR. All consecutive patients with T3 only adenocarcinoma of the head of the pancreas undergoing surgery between December 1998 and June 2011 were included. Multivariable logistic and proportional hazards regression analyses were performed to determine the association between the surgical groups and in-hospital mortality (IHM) and overall survival (OS).

RESULTS

1070 patients were included of whom 840 (78.5%) had PD and 230 (21.5%) had PDVR. Factors independently associated with IHM were a high creatinine (aHR 1.14, p = 0.02), post-operative bleeding (aHR 2.86, p = 0.04) and a re-laparotomy (aHR 8.42, p = 0.0001). For OS, multivariable analyses identified R1 resection margin status (aHR 1.22, p = 0.01), N1 nodal status (aHR 1.92, p = 0.0001), perineural invasion (aHR 1.37, p = 0.002), tumour size >20mm (aHR 0.63, p = 0.0001) and a relaparotomy (aHR 1.84, p = 0.0001) to be independently associated with overall mortality.

CONCLUSION

This study on T3 adenocarcinoma of the head of the pancreas suggests that IHM is strongly associated with perioperative complications whilst OS is affected by histological parameters. Detailed pre-operative disease evaluation and advances in oncological treatment have the potential to improve OS.