Gaussian Process-based prediction of memory performance and biomarker status in ageing and Alzheimer's disease-A systematic model evaluation

Neuroimaging markers based on Magnetic Resonance Imaging (MRI) combined with various other measures (such as genetic covariates, biomarkers, vascular risk factors, neuropsychological tests etc.) might provide useful predictions of clinical outcomes during the progression towards Alzheimer's disease (AD). The use of multiple features in predictive frameworks for clinical outcomes has become increasingly prevalent in AD research. However, many studies do not focus on systematically and accurately evaluating combinations of multiple input features. Hence, the aim of the present work is to explore and assess optimal combinations of various features for MR-based prediction of (1) cognitive status and (2) biomarker positivity with a multi-kernel learning Gaussian process framework. The explored features and parameters included (A) combinations of brain tissues, modulation, smoothing, and image resolution; (B) incorporating demographics & clinical covariates; (C) the impact of the size of the training data set; (D) the influence of dimensionality reduction and the choice of kernel types. The approach was tested in a large German cohort including 959 subjects from the multicentric longitudinal study of cognitive impairment and dementia (DELCODE). Our evaluation suggests the best prediction of memory performance was obtained for a combination of neuroimaging markers, demographics, genetic information (ApoE4) and CSF biomarkers explaining 57% of outcome variance in out-of-sample predictions. The highest performance for Aβ42/40 status classification was achieved for a combination of demographics, ApoE4, and a memory score while usage of structural MRI further improved the classification of individual patient's pTau status.

Ensuring privacy protection in the era of big laparoscopic video data: development and validation of an inside outside discrimination algorithm (IODA)

BACKGROUND

Laparoscopic videos are increasingly being used for surgical artificial intelligence (AI) and big data analysis. The purpose of this study was to ensure data privacy in video recordings of laparoscopic surgery by censoring extraabdominal parts. An inside-outside-discrimination algorithm (IODA) was developed to ensure privacy protection while maximizing the remaining video data.

METHODS

IODAs neural network architecture was based on a pretrained AlexNet augmented with a long-short-term-memory. The data set for algorithm training and testing contained a total of 100 laparoscopic surgery videos of 23 different operations with a total video length of 207 h (124 min ± 100 min per video) resulting in 18,507,217 frames (185,965 ± 149,718 frames per video). Each video frame was tagged either as abdominal cavity, trocar, operation site, outside for cleaning, or translucent trocar. For algorithm testing, a stratified fivefold cross-validation was used.

RESULTS

The distribution of annotated classes were abdominal cavity 81.39%, trocar 1.39%, outside operation site 16.07%, outside for cleaning 1.08%, and translucent trocar 0.07%. Algorithm training on binary or all five classes showed similar excellent results for classifying outside frames with a mean F1-score of 0.96 ± 0.01 and 0.97 ± 0.01, sensitivity of 0.97 ± 0.02 and 0.0.97 ± 0.01, and a false positive rate of 0.99 ± 0.01 and 0.99 ± 0.01, respectively.

CONCLUSION

IODA is able to discriminate between inside and outside with a high certainty. In particular, only a few outside frames are misclassified as inside and therefore at risk for privacy breach. The anonymized videos can be used for multi-centric development of surgical AI, quality management or educational purposes. In contrast to expensive commercial solutions, IODA is made open source and can be improved by the scientific community.

Video-based learning of coping strategies for common errors improves laparoscopy training-a randomized study

AIMS

The aim of this study was to investigate whether shifting the focus to solution orientation and developing coping strategies for common errors could increase the efficiency of laparoscopic training and influence learning motivation. The concept of coping has been particularly defined by the psychologist Richard Lazarus [Lazarus and Folkman in Stress, appraisal, and coping, Springer publishing company, New York, 1984]. Based on this model, we examined the use of observational learning with a coping model for its effectiveness as a basic teaching model in laparoscopic training.

METHODS

55 laparoscopically naive medical students learned a standardized laparoscopic knot tying technique with video-based instructions. The control group was only offered a mastery video that showed the ideal technique and was free from mistakes. The intervention group was instructed on active error analysis and watched freely selectable videos of common errors including solution strategies (coping model) in addition to the mastery videos.

RESULTS

There was no statistically significant difference between the intervention and control groups for number of knot tying attempts until proficiency was reached (18.8 ± 5.5 vs. 21.3 ± 6.5, p = 0.142). However, there was a significantly higher fraction of knots achieving technical proficiency in the intervention group after first use of the coping model (0.7 ± 0.1 vs. 0.6 ± 0.2, p = 0.026). Additionally, the proportion of blinded attempts that met the criteria for technical proficiency was significantly higher for the intervention group at 60.9% vs. 38.0% in control group (p = 0.021). The motivational subscore "interest" of the validated score on current motivation (QCM) was significantly higher for the intervention group (p = 0.032), as well as subjective learning benefit (p = 0.002) and error awareness (p < 0.001).

CONCLUSION

Using video-based learning of coping strategies for common errors improves learning motivation and understanding of the technique with a significant difference in its qualitative implementation in laparoscopy training. The ability to think in a solution-oriented, independent way is necessary in surgery in order to recognize and adequately deal with technical difficulties and complications.

Dynamic alpha factor prediction with operating data - a machine learning approach to model oxygen transfer dynamics in activated sludge

Aeration is an energy-intensive process of aerobic biological wastewater treatment. An accurate model of oxygen transfer dynamics in activated sludge tanks would improve design and operation of aeration systems. Such a model should consider spatial and diurnal variation of α-factor as well as site-specific conditions that impact oxygen transfer. For this dynamic prediction a machine learning approach was used for the first time. The data-driven method was based on long-term ex-situ off-gas measurements with pilot-scale reactors (5.8 m height, 8.3 m³ vol) coupled to full-scale activated sludge tanks on the sites of two conventional and a two-stage activated sludge treatment plant. The ex-situ off-gas method allowed to quantify theoretical off-gas parameters in non-aerated zones and thus consider the whole activated sludge tank. We introduced the α₀-factor to compare aerated and non-aerated zones under nonsteady-state conditions. Like the established α-factor for steady-state conditions, the α₀-factor describes oxygen transfer inhibiting effects in activated sludge. α₀-factor was lowest in upstream denitrification zones. This indicates an anoxic elimination of oxygen transfer inhibiting wastewater contaminants which improved oxygen transfer in subsequent aerobic zones. Random Forest models predicted α₀-factor reliably in all examined activated sludge tanks even for stormwater events and seasonal variation. Model development only required online sensor data already available to operators. Our results suggest that machine learning models can dynamically predict α-factors in a variety of activated sludge processes, thus considering site-specific conditions in model training without manual calibration.

Nurse Preceptors' Experiences of an Online Strength-Based Nursing Course in Clinical Teaching

Background: Online educational programs for nurse preceptors have been created based on various theoretical frameworks; however, no programs using a Strengths-Based Nursing (SBN) approach could be located. Purpose: This qualitative descriptive study explored the nurse preceptors' experiences in using a SBN approach to provide clinical teaching to nursing students after completing an online SBN clinical teaching course. Methods: Semi-structured interviews were conducted with six nurses. Data was thematically analyzed. Findings: Although their levels of familiarity with SBN varied, all preceptors acknowledged that using a SBN approach in clinical teaching benefits both students and educators. They reported that it empowered students and that it allowed them to discover their strengths. Getting to know their students helped the preceptors provide tailored learning experiences and feedback. Using the SBN approach simultaneously enhanced the preceptors' self-confidence and created opportunities for shared learning. Conclusion: Using a strengths' approach offers nurse preceptors a powerful tool to facilitate student learning and skills development in clinical practice.

Serious gaming and virtual reality in the multimodal training of laparoscopic inguinal hernia repair: a randomized crossover study

BACKGROUND

The aim of this study was to assess the transferability of surgical skills for the laparoscopic hernia module between the serious game Touch Surgery™ (TS) and the virtual reality (VR) trainer Lap Mentor™. Furthermore, this study aimed to collect validity evidence and to discuss "sources of validity evidence" for the findings using the laparoscopic inguinal hernia module on TS.

METHODS

In a randomized crossover study, medical students (n = 40) in their clinical years performed laparoscopic inguinal hernia modules on TS and the VR trainer. TS group started with "Laparoscopic Inguinal Hernia Module" on TS (phase 1: Preparation, phase 2: Port Placement and Hernia Repair), performed the module first in training, then in test mode until proficiency was reached. VR group started with "Inguinal Hernia Module" on the VR trainer (task 1: Anatomy Identification, task 2: Incision and Dissection) and also performed the module until proficiency. Once proficiency reached in the first modality, the groups performed the other training modality until reaching proficiency. Primary endpoint was the number of attempts needed to achieve proficiency for each group for each task/phase.

RESULTS

Students starting with TS needed significantly less attempts to reach proficiency for task 1 on the VR trainer than students who started with the VR trainer (TS = 2.7 ± 0.6 vs. VR = 3.2 ± 0.7; p = 0.028). No significant differences for task 2 were observed between groups (TS = 2.3 ± 1.1 vs. VR = 2.1 ± 0.8; p = 0.524). For both phases on TS, no significant skill transfer from the VR trainer to TS was observed. Aspects of validity evidence for the module on TS were collected.

CONCLUSION

The results show that TS brought additional benefit to improve performances on the VR trainer for task 1 but not for task 2. Skill transfer from the VR trainer to TS could not be shown. VR and TS should thus be used in combination with TS first in multimodal training to ensure optimal training conditions.

Secondary prevention in diabetic and nondiabetic coronary heart disease patients: Insights from the German subset of the hospital arm of the EUROASPIRE IV and V surveys

BACKGROUND

Patients with coronary heart disease (CHD) with and without diabetes mellitus have an increased risk of recurrent events requiring multifactorial secondary prevention of cardiovascular risk factors. We compared prevalences of cardiovascular risk factors and its determinants including lifestyle, pharmacotherapy and diabetes mellitus among patients with chronic CHD examined within the fourth and fifth EUROASPIRE surveys (EA-IV, 2012-13; and EA-V, 2016-17) in Germany.

METHODS

The EA initiative iteratively conducts European-wide multicenter surveys investigating the quality of secondary prevention in chronic CHD patients aged 18 to 79 years. The data collection in Germany was performed during a comprehensive baseline visit at study centers in Würzburg (EA-IV, EA-V), Halle (EA-V), and Tübingen (EA-V).

RESULTS

384 EA-V participants (median age 69.0 years, 81.3% male) and 536 EA-IV participants (median age 68.7 years, 82.3% male) were examined. Comparing EA-IV and EA-V, no relevant differences in risk factor prevalence and lifestyle changes were observed with the exception of lower LDL cholesterol levels in EA-V. Prevalence of unrecognized diabetes was significantly lower in EA-V as compared to EA-IV (11.8% vs. 19.6%) while the proportion of prediabetes was similarly high in the remaining population (62.1% vs. 61.0%).

CONCLUSION

Between 2012 and 2017, a modest decrease in LDL cholesterol levels was observed, while no differences in blood pressure control and body weight were apparent in chronic CHD patients in Germany. Although the prevalence of unrecognized diabetes decreased in the later study period, the proportion of normoglycemic patients was low. As pharmacotherapy appeared fairly well implemented, stronger efforts towards lifestyle interventions, mental health programs and cardiac rehabilitation might help to improve risk factor profiles in chronic CHD patients.

The Evolution of Feeding Mechanics in the Danioninae, or Why Giant Danios Don't Suck Like Zebrafish

By linking anatomical structure to mechanical performance we can improve our understanding of how selection shapes morphology. Here we examined the functional morphology of feeding in fishes of the subfamily Danioninae (order Cypriniformes) to determine aspects of cranial evolution connected with their trophic diversification. The Danioninae comprise three major lineages and each employs a different feeding strategy. We gathered data on skull form and function from species in each clade, then assessed their evolutionary dynamics using phylogenetic-comparative methods. Differences between clades are strongly associated with differences in jaw protrusion. The paedomorphic Danionella clade does not use jaw protrusion at all, members of the Danio clade use jaw protrusion for suction production and prey capture, and members of the sister clade to Danio (e.g., Devario and Microdevario) use jaw protrusion to retain prey after capture. The shape of the premaxillary bone is a major determinant of protrusion ability, and premaxilla morphology in each of these lineages is consistent with their protrusion strategies. Premaxilla shapes have evolved rapidly, which indicates that they have been subjected to strong selection. We compared premaxilla development in giant danio (Devario aequipinnatus) and zebrafish (Danio rerio) and discuss a developmental mechanism that could shift danionine fishes between the feeding strategies employed by these species and their respective clades. We also identified a highly integrated evolutionary module that has been an important factor in the evolution of trophic mechanics within the Danioninae.

Health inequalities in very old age: Continuity, accumulation or convergence?

Background

Health inequalities are well documented empirically. However, it is unclear whether health inequalities persist in very old age (continuity), whether they accumulate steadily (accumulation), or whether they even attenuate in old age (convergence) - not least because of social inequalities in life expectancy, which make it less likely for individuals with lower social status to reach old age at all. The aim of this study is to empirically test these three hypotheses.

Methods

The analyses are based on representative cross-sectional data from 1,863 very old people and panel data from 912 participants in the 1st and 2nd wave (W1, W2) living in North Rhine-Westphalia the largest federal state in Germany (NRW80+ study). Health outcomes of the analyses are subjective health, multimorbidity and need for long-term care. Indicators of socioeconomic status (SES) are education, occupational status, and net equivalent income. Regression models (linear, logistic, ordinal) are used to analyze cross-sectional and longitudinal data. Panel selectivity is also considered by means of a failure model.

Results

Cross-sectional findings show health inequalities for all SES variables: persons with low education and low income have poorer subjective health and higher need for care. Low status is associated with higher need for care. Preliminary results from longitudinal analyses show a slight increase in health inequality: low income and low status are associated with higher multimorbidity and low education with higher dependency on long-term care at W2.

Conclusions

Despite the socially conditioned unequal chances of reaching old age, health inequality is still present in very old age and even increases slightly over time. The results argue against the convergence hypothesis and in favor of the continuity or even the accumulation hypothesis. A better understanding of the mechanisms leading to the persistent inequality is needed to development targeted interventions also in old age.

Key messages

• Health inequalities persist and even increase in very old age (80+).

• It is imperative that the oldest old – an increasingly large population group – be considered when designing strategies to reduce health inequalities.

Caught between competing emotions and tensions - a focus group study exploring experiences of family caregivers of out-of-hospital cardiac arrest survivors

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Being a family member caring for an out-of-hospital cardiac arrest (OHCA) survivor may impact family caregivers’ lives due to the sudden onset of the illness and possible secondary cognitive, emotional and physical challenges. However, experiences of caring for an OHCA survivor are sparsely described.

Purpose

This purpose of this study was to explore the subjective experiences of family caregivers of OHCA survivors as a means of understanding the potential burden they face.

Methods

Using an explorative qualitative approach, six focus group interviews were conducted with a sample of 25 family caregivers of OHCA survivors and analysed using a phenomenological hermeneutic approach inspired by the philosophy of Ricoeur. OHCA survivors and their family caregivers were attenting at a residential rehabilitation course, where the caregivers were interviewed as part of the course.

Results

Three themes emerged: i) Feeling unexpectedly alone and invisible; the family caregivers felt an emotional burden that could not be shared – leading to caregiving being a lonely and anxious experience. The family caregiver felt alone with the responsibility of the shared life, ii) Fear of loss; the fear of losing a loved one was a constant companion contributing to the burden of caregiving, and iii) Adjusting to a new everyday life; the family caregivers had difficulties adjusting to living their lives on the basis of the survivors’ needs. This often resulted in an existential crisis trying to adapt (Figure 1).

Conclusion

The findings of this study illuminate and emphasise the burden experienced by family caregivers and how they can be caught between competing emotions and tensions. The possible caregiver burden following OHCA should be acknowledged.

Systematic screening is needed to identify those at risk of high caregiver burden. Further, collaboration with family care givers should be an essential part of post-cardiac arrest care, and interventions to reduce the burden should be tested and implemented as part of the clinical care of OHCA survivors and their families.

Radiomics Can Distinguish Pediatric Supratentorial Embryonal Tumors, High-Grade Gliomas, and Ependymomas

BACKGROUND AND PURPOSE

Pediatric supratentorial tumors such as embryonal tumors, high-grade gliomas, and ependymomas are difficult to distinguish by histopathology and imaging because of overlapping features. We applied machine learning to uncover MR imaging-based radiomics phenotypes that can differentiate these tumor types.

MATERIALS AND METHODS

Our retrospective cohort of 231 patients from 7 participating institutions had 50 embryonal tumors, 127 high-grade gliomas, and 54 ependymomas. For each tumor volume, we extracted 900 Image Biomarker Standardization Initiative-based PyRadiomics features from T2-weighted and gadolinium-enhanced T1-weighted images. A reduced feature set was obtained by sparse regression analysis and was used as input for 6 candidate classifier models. Training and test sets were randomly allocated from the total cohort in a 75:25 ratio.

RESULTS

The final classifier model for embryonal tumor-versus-high-grade gliomas identified 23 features with an area under the curve of 0.98; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 0.85, 0.91, 0.79, 0.94, and 0.89, respectively. The classifier for embryonal tumor-versus-ependymomas identified 4 features with an area under the curve of 0.82; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 0.93, 0.69, 0.76, 0.90, and 0.81, respectively. The classifier for high-grade gliomas-versus-ependymomas identified 35 features with an area under the curve of 0.96; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 0.82, 0.94, 0.82, 0.94, and 0.91, respectively.

CONCLUSIONS

In this multi-institutional study, we identified distinct radiomic phenotypes that distinguish pediatric supratentorial tumors, high-grade gliomas, and ependymomas with high accuracy. Incorporation of this technique in diagnostic algorithms can improve diagnosis, risk stratification, and treatment planning.

Relationship between psychological characteristics, personality traits, and training on performance in a neonatal resuscitation scenario: A machine learning based analysis

BACKGROUND

In life-threatening emergency events, prompt decision-making and accurate reactions are essential for saving a human's life. Some of these skills can be improved by regular simulation trainings. However, besides these factors, individual characteristics may play a significant role in the patients' outcome after a resuscitation event. This study aimed to differentiate personality characteristics of team members who take responsibility for their actions, contextualizing the effect of training on resuscitation performance.

METHODS

Six hundred and two third-year medical students were asked to answer psychological and personality questionnaires. Fifty-five of them performed in a neonatal simulation resuscitation scenario. To assess participants' performances in the NLS scenario, we used a scenario-based designed NLS checklist. A machine learning design was utilized to better understand the interaction of psychological characteristics and training. The first model aimed to understand how to differentiate between people who take responsibility for their actions vs. those who do not. In a second model, the goal was to understand the relevance of training by contextualizing the effect of training to other important psychological and personality characteristics like locus of control, anxiety, emotion regulation, openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism.

RESULTS

No statistically significant differences were found for psychological characteristics between the training group and the no training group. However, as expected, differences were noted in favor of the training group for performance and within gender for psychological characteristics. When correcting for all these information in a model, anxiety and gender were the most important factors associated with taking responsibility for an action, while training was the only relevant factor in explaining performance during a neonatal resuscitation scenario.

CONCLUSION

Training had a significantly stronger effect on performance in medical students in a neonatal resuscitation scenario than individual characteristics such as demographics, personality, and trait anxiety.

Triangle Singularity as the Origin of the a_{1}(1420)

The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a_{1}(1420), decaying to f_{0}(980)π. With a mass too close to and a width smaller than the axial-vector ground state a_{1}(1260), it was immediately interpreted as a new light exotic meson, similar to the X, Y, Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a_{1}(1260) resonance into K^{*}(→Kπ)K[over ¯] and subsequent rescattering through a triangle singularity into the coupled f_{0}(980)π channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having fewer parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonancelike structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.

Improving aeration systems in saline water (part II): effect of different salts and diffuser type on oxygen transfer of fine-bubble aeration systems

The objective of the present study is to investigate the different effects on the oxygen transfer of fine-bubble aeration systems in saline water. Compared to tap water, oxygen transfer increases due to the inhibition of bubble coalescence. In Part I of the present study, we investigated in laboratory-scale experiments the effect of design of diffuser membrane. The objective of Part II is the assessment of effects of different salts, diffuser type and diffuser density. We measured the concentration of various salts (MgCl₂; CaCl₂; Na₂SO₄; NaCl; KCl) above which coalescence is fully inhibited and oxygen transfer reaches its maximum (referred to as the critical coalescence concentration; CCC). For this purpose, we developed a new analytical approach, which enables investigation of the coalescence behaviour of any aeration system and (mixed) salt solution quickly and easily by evaluating the results of oxygen transfer tests. To investigate the transferability to large scale and the effect of diffuser type and density, we repeated lab-scale experiments in a 17,100 L pilot-scale test tank and carried out additional tests with tube and plate diffusers at different diffuser densities. The results show that despite the higher pressure drop, diffusers with dense slit density and smaller slits are to be recommended in order to improve efficiency of aeration systems in saline water.

Grief and loss in old age: Exploration of the association between grief and depression

BACKGROUND

The proportion of older adults is increasing due to demographic changes. Depression belongs to the most common mental disorders in late life. The loss of an emotionally significant person is a risk factor for the development of depression. The aim of this study is to analyze the association between depression and grief burden resulting from loss. Based on prior evidence, we examined loneliness as a possible mediator and social support as possible moderator of this association.

METHODS

The cross-sectional analyses are based on a sample (N = 863) of study participants aged 75+ (M = 81.4 years, SD = 4.4, 62.2% female) with loss experience deriving from the multicenter prospective German cohort study AgeMooDe. Regression analyses (moderated mediation) were performed.

RESULTS

With increasing age (β = 0.10, p = .005) and grief burden (β = 0.33, p <. 001) depression severity increased. There was an indirect mediating effect of loneliness on the correlation of grief burden and depression (b = 0.04, CI [0.03, 0.05]), but no moderating effect of social support on the correlation of grief burden and loneliness. People living alone had a significantly higher risk of depression, increased loneliness and lack of social support.

LIMITATIONS

Assessments were based on self-reporting and recorded dimensionally. The cross-sectional design limits conclusions about directions and causality of associations. Sampling bias cannot be completely excluded.

CONCLUSION

The study provides empirical evidence and a better understanding of the association between grief and depression among the very old and the mediating role of loneliness.

Investigation of gamma secretase gene complex mutations in German population with Hidradenitis suppurativa designate a complex polygenic heritage

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory disease affecting apocrine gland-bearing skin in the axilla, groin and under the breasts. Mutations of the gamma secretase gene complex, which is essential in the activation of Notch signalling pathways, were shown in some families with HS and in a few sporadic cases. Although an imbalance in Notch signalling is implicated in the pathogenesis, the exact mechanism of HS development is yet unknown.

OBJECTIVES

We aim to investigate the genetic basis of HS by determining the presence of mutations of gamma secretase gene complex in a cohort of HS patients and by searching for a disease-causing pathogenic variant in a multi-generational HS family using parametric linkage analysis.

METHODS

Thirty-eight patients clinically diagnosed with HS were included in this study. All exons and exon-intron boundaries of the genes encoding gamma secretase complex consisting of six genes: APH1A, APH1B, PSENEN, NCSTN, PSEN1 and PSEN2 were sequenced by Sanger technique. Genetic mapping with parametric linkage analysis for the patients in the family was performed with eight affected and four healthy individuals. The logarithm of odds was calculated.

RESULTS

In a sporadic patient with early-onset, severe lesions in axilla and groin, a novel single-nucleotide deletion causing frameshift in exon 1 of the NCSTN gene was identified ((NM_015331.3): c.38delG, p.(Gly13Glufs*15)). The LOD score of 1.5 was never exceeded in any region of the genome, pointing towards intricate multi-genic inheritance pattern within the affected family.

CONCLUSIONS

The gamma secretase gene complex mutations were rare in our cohort (3.2%). Besides, our analysis indicates a possible complex multi-genic inheritance in a seemingly autosomal dominantly inherited large HS family. Genetics of both familial and sporadic HS may be complicated in most cases, and the role of other potential genes such as autoinflammatory and modifier genes as well as environmental factors may influence the pathogenesis.

Cross-sectional prevalence of SARS-CoV-2 antibodies in healthcare workers in paediatric facilities in eight countries

Background

Healthcare workers (HCWs) have been disproportionately affected by coronavirus disease 2019 (COVID-19), which may be driven, in part, by nosocomial exposure. If HCW exposure is predominantly nosocomial, HCWs in paediatric facilities, where few patients are admitted with COVID-19, may lack antibodies to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and be at increased risk during the current resurgence.

Aim

To compare the seroprevalence of SARS-CoV-2 amongst HCWs in paediatric facilities in seven European countries and South Africa (N=8).

Methods

All categories of paediatric HCWs were invited to participate in the study, irrespective of previous symptoms. A single blood sample was taken and data about previous symptoms were documented. Serum was shipped to a central laboratory in London where SARS-CoV-2 immunoglobulin G was measured.

Findings

In total, 4114 HCWs were recruited between 1^st May and mid-July 2020. The range of seroprevalence was 0–16.93%. The highest seroprevalence was found in London (16.93%), followed by Cape Town, South Africa (10.36%). There were no positive HCWs in the Austrian, Estonian and Latvian cohorts; 2/300 [0.66%, 95% confidence interval (CI) 0.18–2.4] HCWs tested positive in Lithuania; 1/124 (0.81%, 95% CI 0.14–4.3) HCWs tested positive in Romania; and 1/76 (1.3%, 95% CI 0.23–7.0) HCWs tested positive in Greece.

Conclusion

Overall seroprevalence amongst paediatric HCWs is similar to their national populations and linked to the national COVID-19 burden. Staff working in paediatric facilities in low-burden countries have very low seroprevalence rates and thus are likely to be susceptible to COVID-19. Their susceptibility to infection may affect their ability to provide care in the face of increasing cases of COVID-19, and this highlights the need for appropriate preventative strategies in paediatric healthcare settings.

Self-assembled hybrid organic-MoS3-nanoparticle catalyst for light energy conversion

We present photocatalytically active, stable polymer-amorphous-MoS3-nanoparticle hybrid structures in aqueous solution. Below 10 nm MoS3 particles in the polymer exhibit an up to 7.5-fold increased photocatalytic activity compared to the neat nanoparticles without any additional photosensitizer. Supramolecular interactions are key in directing the structure formation of the hybrid assembly. The hybrid structures bear potential as novel affordable photocatalysts for solar energy conversion.

Flow Cytometric Assessment of AKT Signaling in Platelet Activation: An Alternative Diagnostic Tool for Small Volumes of Blood

INTRODUCTION

 The diagnosis of platelet function disorder in children is challenging. Light transmission aggregometry is the gold standard for platelet function disorders. However, large blood volumes are required. Currently, there are no existing tools for the diagnosis of platelet function disorders that use small blood volumes. AKT signaling plays a central role in platelet activation during hemostasis and might be visualized by flow cytometry.

METHODS

 Platelet-rich plasma obtained by centrifugation of citrated blood from healthy volunteers was activated with arachidonic acid, thrombin receptor activating peptide-6 (TRAP-6), collagen, adenosine diphosphate ADP, collagen-related peptide (CRP), and epinephrine. After platelet activation, the phosphorylation of AKT was assessed by flow cytometer using a Navios cytometer.

RESULTS

 Healthy volunteers showed a reproducible phosphorylation of AKT upon activation. In comparison to nonactivated platelets, we documented an increase in pAKT expression with all agonists. Especially TRAP-6 and CRP caused considerable increase in percentage of pAKT expression throughout all the tested healthy volunteers.

CONCLUSION

 An activation of the AKT-signal pathway by different agonists can clearly be detected on the flow cytometer, indicating that the visualization of signaling in platelets by flow cytometry might be an efficient alternative for light transmission aggregometry to test platelet function in children.

PLK2 is a novel regulator of osteopontin-driven fibrosis and diastolic dysfunction in permanent atrial fibrillation

Background and aim

Atrial fibrillation (AF) is frequently accompanied by cardiac fibrosis and diastolic heart failure. Due to the heterogeneous nature and complexity of fibrosis, the knowledge of the underlying pathomechanisms is limited. Thus, effective antifibrotic pharmacotherapy is missing. The objective of this study was to decipher the role of polo-like kinase 2 (PLK2) in the pathogenesis of cardiac fibrosis and left ventricular diastolic dysfunction. We put particular emphasis on the identification of profibrotic downstream targets of PLK2, which can serve as therapeutic targets.

Methods and results

This study was based on human atrial tissue biopsies and peripheral blood samples, a PLK2 knockout mouse model, a canine tachy-pacing model and specific pharmacological interventions on cardiac fibroblasts. In human atrial AF tissue samples, PLK2 was 50% downregulated by hypoxia-induced promoter methylation compared to sinus rhythm (SR) control. Confirmatory analysis of a canine tachy-pacing model showed PLK2 downregulation exclusively in the atria but not in the ventricles. Specific pharmacological inhibition as well as genetic deletion of PLK2 led to a striking myofibroblast phenotype. Discovery proteomics revealed that the global knockout of PLK2 resulted in de novo secretion of the inflammatory cytokine osteopontin (OPN) in cardiac fibroblasts and concomitant ventricular fibrosis in the PLK2 knockout mouse model. An ELISA analysis of peripheral blood samples of AF patients with electrophysiologically proven fibrosis, confirmed significantly increased OPN plasma concentrations compared to SR and non-fibrosis AF controls. Consequently, echocardiography on PLK2 KO mice revealed left ventricular diastolic dysfunction, tachycardia and fibrosis-typical surface ECG anomalies (PQ and QRS prolongation). Mechanistically, we identified the ERK1/2 signaling pathway as the molecular link between reduced expression of PLK2 and elevated osteopontin transcription. In a reverse translational attempt, we successfully tested the capability of 5-amino-salicylic acid (5-ASA) to inhibit osteopontin transcription and to reverse a TGF-β-induced myofibroblast phenotype in vitro. Currently the long-term administration of 5-ASA is tested in PLK2 knockout mice to evaluate the therapeutic potential to prevent cardiac fibrosis and diastolic heart failure development.

Conclusion and clinical impact

We identified PLK2 as an epigenetically regulated kinase involved in the pathophysiology of fibrosis in AF. PLK2 knockout mice can serve as a model of diastolic heart failure wherein OPN is a promising therapeutic target. Our results strengthen the current hypothesis that atrial fibrillation is not only an ion channel disease but a complex systemic disorder. Restoration of physiological PLK2 expression and blockade of osteopontin release with 5-ASA may constitute valuable new drug targets for the prevention and treatment of fibrosis and diastolic heart failure in AF.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Faculty of Medicine, Carl Gustav Carus, Dresden, “MeDDrive Start” Grant

The temporal association between incident late-life depression and incident dementia

OBJECTIVE

There is an established association between depression and subsequent dementia. The present study examined temporal associations between incident late-life depression and subsequent dementia, also considering age and sex.

METHODS

We used longitudinal health claims data from the largest German health insurance provider ('Allgemeine Ortskrankenkasse') considering up to 9 follow-up years in piecewise exponential models. ICD-10 codes were used to define incident depression and dementia in individuals ≥65 years (n = 97 110).

RESULTS

Incident depression was associated with a higher risk of subsequent dementia (incidence rate ratios (IRR) adjusted for age and sex: IRR = 1.58, 95% CI = 1.51-1.64). The strongest association was found for the shortest interval of 1 quarter (IRR = 2.04, 95% CI = 1.88-2.21), with significant associations up to an interval of roughly 3 years. The association was more pronounced and lasted for more quarters in the younger portion of this study group (ages from 65-74: IRR = 2.00, 95% CI = 1.83-2.18; 75-84: IRR = 1.64, 95% CI = 1.55-1.73; ≥85: IRR = 1.19, 95% CI = 1.08-1.31). It was stronger among men than women (men: IRR = 1.98, 95% CI = 1.84-2.14; women: IRR = 1.44, 95% CI = 1.37-1.51) with no sex-specific temporal association.

CONCLUSION

This large claims data study confirmed that incident late-life depression is associated with a higher risk of dementia within the 3 years following diagnosis. Hence, incident late-life depression should prompt further cognitive examinations and referrals to specialists. This might apply especially to younger seniors and men.

The polygenic risk for obsessive-compulsive disorder is associated with the personality trait harm avoidance

OBJECTIVE

Obsessive-compulsive disorder (OCD) is a complex psychiatric disorder with a substantial genetic contribution. While the specific variants underlying OCD's heritability are still unknown, findings from genome-wide association studies (GWAS) corroborate the importance of common SNPs explaining the phenotypic variance in OCD. Investigating associations between the genetic liability for OCD, as reflected by a polygenic risk score (PRS), and potential endophenotypes of the disorder, such as the personality trait harm avoidance, may aid the understanding of functional pathways from genes to diagnostic phenotypes.

METHODS

We derived PRS for OCD at several P-value thresholds based on the latest Psychiatric Genomics Consortium OCD GWAS (2688 cases, 7037 controls) in an independent sample of OCD patients (n = 180), their unaffected first-degree relatives (n = 108) and healthy controls (n = 200). Using linear regression, we tested whether these PRS are associated with the personality trait harm avoidance.

RESULTS

Results showed that OCD PRS significantly predicted OCD status, with patients having the highest scores and relatives having intermediate scores. Furthermore, the genetic risk for OCD was associated with harm avoidance across the entire sample, and among OCD patients. As indicated by mediation analyses, harm avoidance mediated the association between the OCD PRS and OCD caseness. These results were observed at multiple P-value thresholds and persisted after the exclusion of patients with a current comorbid major depressive or anxiety disorder.

CONCLUSION

Our findings support the polygenic nature of OCD and further validate harm avoidance as a candidate endophenotype and diathesis of OCD.

Cognition, loneliness and social isolation: A cross-national, longitudinal exploration

Background

One of the challenges to ageing individuals and health care systems is the decline in cognitive function with increasing age. The present study investigates in which way loneliness and social isolation is associated with cognitive decline in an aged population in Europe. Furthermore, it investigates how these relationships vary across different cultural and social settings.

Methods

The study employs panel data from the Survey of Health, Ageing and Retirement in Europe (SHARE). Data from respondents aged 50+ from 16 European countries were collected from 2011-2017 at up to four points in time. Loneliness was operationalized as the perception of feeling lonely, while social isolation was operationalized by a summary index of social network size and social interaction. The cognitive function measures included tests of verbal fluency, as well as immediate and delayed recall. A linear panel fixed-effects modelling approach was used, while controlling for potential time-variant confounders from the areas of demographics, mental and physical health and survey methodological characteristics.

Results

Preliminary results show that loneliness and social isolation are associated with cognitive decline, while the extent varied by the measure of cognitive functioning measured. Loneliness, social isolation and cognition descriptively all show substantial cross-national variation.

Conclusions

The study illustrates the impact of loneliness and social isolation on cognitive functioning across a number of European countries. Cognitive functioning is an important determinant to successful ageing, preventing its decline promotes self-sufficient, independent living in the elderly and good quality end-of-life. This can support the development of implementable and accessible prevention for at risk individuals.

Key messages

Investigating the impact of social isolation and loneliness on the cognitive functioning can help tailor easily accessible prevention measures of cognitive decline in the elderly. The study allows for the assessment of cross-cultural differences and need for targeted measures across a number of European countries.

Cognitive and emotional empathy in individuals at clinical high risk of psychosis

BACKGROUND

Impairments of social cognition are considered core features of schizophrenia and are established predictors of social functioning. However, affective aspects of social cognition including empathy have far less been studied than its cognitive dimensions. The role of empathy in the development of schizophrenia remains largely elusive.

METHODS

Emotional and cognitive empathy were investigated in large sample of 120 individuals at Clinical High Risk of Psychosis (CHR-P) and compared with 50 patients with schizophrenia and 50 healthy controls. A behavioral empathy assessment, the Multifaceted Empathy Test, was implemented, and associations of empathy with cognition, social functioning, and symptoms were determined.

RESULTS

Our findings demonstrated significant reductions of emotional empathy in individuals at CHR-P, while cognitive empathy appeared intact. Only individuals with schizophrenia showed significantly reduced scores of cognitive empathy compared to healthy controls and individuals at CHR-P. Individuals at CHR-P were characterized by significantly lower scores of emotional empathy and unspecific arousal for both positive and negative affective valences compared to matched healthy controls and patients with schizophrenia. Results also indicated a correlation of lower scores of emotional empathy and arousal with higher scores of prodromal symptoms.

CONCLUSION

Findings suggest that the tendency to 'feel with' an interaction partner is reduced in individuals at CHR-P. Altered emotional reactivity may represent an additional, early vulnerability marker, even if cognitive mentalizing is grossly unimpaired in the prodromal stage. Different mechanisms might contribute to reductions of cognitive and emotional empathy in different stages of non-affective psychotic disorders and should be further explored.

P457Incidence of LA fibrosis and substrate-based AF ablation success rates in HF patients

Funding Acknowledgements

The author(s) received no specific funding for this work.

Background

In heart failure (HF) patients, sinus rhythm maintenance after catheter ablation for atrial fibrillation (AF) is mandatory to achieve better long-term outcome. Presence of left atrial (LA) fibrosis significantly attenuates ablation success rates. Incidence of LA fibrosis and the effect of an individualized substrate-based ablation concept on rhythm outcome in HF patients with AF is unclear.

Methods

This study investigated 103 patients (64 years, 69% men) with persistent AF (79%) and left ventricular (LV) dysfunction (EF 33% IQR [25; 38]) undergoing first time AF ablation. Identification of LA fibrosis and selection of ablation strategy were based on sinus rhythm voltage mapping. All patients received pulmonary vein isolation (PVI). LA fibrosis ablation was individualized by (i) homogenization of small areas, (ii) linear lesions connecting fibrosis and anatomical obstacles and (iii) linear lesions isolating large fibrotic areas. Rhythm outcome was measured by continuous device monitoring (AF detection ≥ 6 min) or Holter-ECG. A total post-procedural AF burden &lt; 0.1% was defined as successful rhythm control.

Results

LA fibrosis in the overall cohort, in paroxysmal and persistent AF patients was detected in 39/103 (38%), 6/22 (27%) and 33/81 (41%), respectively. After 11 ± 5 months and 1.2 procedures/patient, freedom from AF recurrence was similar between patients with and without LA fibrosis (33/39 (84%) vs. 54/64 (84%); p = 0.485). With continuous monitoring, 73/87 (84%) patients recorded a total AF burden &lt; 0.1%. There was no significant difference in AF burden outcome between patients with and without LA fibrosis (3.1% SD ±17.4 vs. 2.2% SD ±8.1; p = 0.4). No correlation between presence or extent of LA fibrosis and AF burden was found; p = 0.299.

Conclusion

A substantial number of HF patients with AF have no evidence of LA fibrosis. Among HF patients with LA fibrosis, individualized substrate-based AF ablation beyond PVI was able to achieve similar ablation success.

Dietary patterns are related to cognitive functioning in elderly enriched with individuals at increased risk for Alzheimer's disease

Purpose

To investigate cross-sectional associations between dietary patterns and cognitive functioning in elderly free of dementia.

Methods

Data of 389 participants from the German DELCODE study (52% female, 69 ± 6 years, mean Mini Mental State Score 29 ± 1) were included. The sample was enriched with elderly at increased risk for Alzheimer’s disease (AD) by including participants with subjective cognitive decline, mild cognitive impairment (MCI) and siblings of AD patients. Mediterranean and MIND diets were derived from 148 Food Frequency Questionnaire items, and data-driven patterns by principal component analysis (PCA) of 39 food groups. Associations between dietary patterns and five cognitive domain scores were analyzed with linear regression analyses adjusted for demographics (model 1), and additionally for energy intake, BMI, other lifestyle variables and APOe4-status (model 2). For PCA-derived dietary components, final model 3 included all other dietary components.

Results

In fully adjusted models, adherence to Mediterranean and MIND diet was associated with better memory. The ‘alcoholic beverages’ PCA component was positively associated with most cognitive domains. Exclusion of MCI subjects (n = 60) revealed that Mediterranean and MIND diet were also related to language functions; associations with the alcoholic beverages component were attenuated, but most remained significant.

Conclusion

In line with data from elderly population samples, Mediterranean and MIND diet and some data-derived dietary patterns were related to memory and language function. Longitudinal data are needed to draw conclusions on the putative effect of nutrition on the rate of cognitive decline, and on the potential of dietary interventions in groups at increased risk for AD.

Electronic supplementary material

The online version of this article (10.1007/s00394-020-02257-6) contains supplementary material, which is available to authorized users.

[Statement of the Austrian Society of Pneumology (ASP)]

The COVID-19 pandemic is currently a challenge worldwide. In Austria, a crisis within the health care system has so far been avoided. The treatment of patients with community-acquired pneumonia (CAP), including SARS-CoV‑2 infections, should continue to be based on evidence-based CAP guidelines during the pandemic. However, COVID-19-specific adjustments are useful. The treatment of patients with chronic lung diseases must be adapted during the pandemic, but must still be guaranteed.

Conceptualization of an ICU Infrastructure for Simulation Based Education in Medical Engineering & eHealth

The use of simulation-based training is gaining importance in medical as well as engineering related education. The complex environment of an intensive care unit is characterized by a high need of interaction between clinical as well as technical components and views. These diverse interactions and the connected requirements are the focus for the presented simulation infrastructure, enabling research, education and training. The presented concept of a modular and flexible intensive care environment provides a high degree of interoperability and flexibility for individual research questions and full support of connectivity for typical clinical workflows. The presented simulation and testing bed will allow both, education for engineering and medical students using patient simulation and simultaneous data transfer as well as research on medical workflows, infrastructural demands and connectivity conformance questions.

Optimizing water-reuse and increasing water-saving potentials by linking treated industrial and municipal wastewater for a sustainable urban development

New industrial and urban developments in water-scarce regions are often inhibited by their high demand for water from natural resources. In addition, there often is a lack of water for purposes that contribute to an improved quality of life, such as urban green spaces. Therefore, the integrated industrial-urban water-reuse concept presents a strategy by linking and reusing treated industrial and municipal wastewater flows to increase urban water-reuse potentials. The concept of combining different reuse water flows, from wastewater treatment plants from industrial parks, aims at significantly increasing the water-saving potentials compared to a separate consideration of the industrial wastewater flows.