A High Temperature Harvestorer Based on a Photovoltaic Cell and an Oxygen Ion Battery

Hybrid devices for combined energy harvesting and storage, i.e., harvestorers, are attractive solutions for powering small autonomous devices (e.g., "smart appliances", Internet of things nodes), which are ever more prominent as the digitalization and technologization of our society progresses. A concept for a high temperature (HT) harvestorer is presented, and the operational characteristics of a prototype device are discussed. It is based on photovoltaic (PV) energy harvesting and HT electrochemical energy storage. The HT-PV cells employ SrTiO3/La0.9Sr0.1CrO3-δ heterojunctions for energy harvesting and produce photovoltages up to 1 V and photocurrents of several mA cm-2 upon UV illumination at 350 °C. Electrochemical energy storage is realized by oxygen ion battery (OIB), a device based on mixed ionic and electronic conducting oxide thin film electrodes and an yttria stabilized zirconia electrolyte. The OIB exhibits capacities of up to 11 mC cm-2 (3 μA h cm-2) at 0.6 V (350 °C). A prototype harvestorer device was fabricated by integrating an HT-PV and an OIB cell into one device. This harvestorer was operated over several cycles consisting of harvesting and storing energy under illumination, followed by retrieval of the stored energy without illumination. Up to 3.5 mJ cm-2 (1 μW h cm-2) was stored with energy efficiencies up to 67%. Approaches for further optimization are discussed.

Non-surgical external jugular vein catheterization using an ear vein access in piglets

The objective of this study was to investigate the feasibility of external jugular vein catheterization through an ear vein in piglets. Forty-six sevoflurane-midazolam anaesthetized piglets were included. External jugular vein catheterization was conducted through the ear vein using the Seldinger technique. Part 1 (n = 27): optimal puncture site was based on the deltoid tuberosity as a landmark to reach the external jugular vein. The final position of the catheter was verified in 25 piglets using computer tomography. Catheterization time was recorded and patency of the catheter assessed by repeated blood sampling for up to 4 h. Part 2 (n = 19): ear vein catheterization was without taking into account any landmarks. Functionality for blood sampling was evaluated as described in part 1. Catheter advancement was possible in 25/27 and 18/19 piglets in parts 1 and 2, respectively. Median (range) time required for successful catheterization was 1.95 (1-10) min (n = 38). The deltoid tuberosity was a good landmark to reach the external jugular vein. But blood sampling was also possible through catheters ending slightly cranial to the external jugular vein. Despite successful catheter advancement, blood sampling was not possible from one catheter in each part of the study (total: two piglets). One of these catheters presented luminal damage, while the other one presented as normal after being removed from the animal. Summarizing, central vein catheterization through the ear vein was feasible in 93.5% and repeated blood sampling was possible in 89.1% of the piglets (n = 46).

Closed-Pore Formation in Oxygen Electrodes for Solid Oxide Electrolysis Cells Investigated by Impedance Spectroscopy

Electrochemical impedance spectroscopy was used to investigate the chemical capacitance of La_0.6Sr_0.4CoO_3-δ (LSC) thin-film electrodes under anodic polarization (i.e., in the electrolysis mode). For this purpose, electrodes with different microstructures were prepared via pulsed-laser deposition. Analysis of dense electrodes and electrodes with open porosity revealed decreasing chemical capacitances with increasing anodic overpotentials, as expected from defect chemical considerations. However, extremely high chemical capacitance peaks with values in the range of 10⁴ F/cm³ at overpotentials of >140 mV were obtained after annealing for several hours in synthetic air and/or after applying high anodic bias voltages of >750 mV. From the results of several surface analysis techniques and transmission electron microscopy, it is concluded that closed pores develop upon both of these treatments: (i) During annealing, initially open pores get closed by SrSO₄, which forms due to strontium segregation in measurement gases with minute traces of sulfur. (ii) The bias treatment causes mechanical failure and morphological changes including closed pores in the bulk of dense films. Under anodic polarization, high-pressure oxygen accumulates in those closed pores, and this causes the capacitance peak. Model calculations based on a real-gas equation allow us to properly predict the experimentally obtained capacitance increase. We demonstrate that analysis of the chemical capacitance of oxygen electrodes in solid oxide electrolysis cells can thus be used as a nondestructive observation tool to detect and quantify closed porosity with a lower detection limit between 10^-4 and 10^-3.

Noise-optimized virtual monoenergetic reconstructions of dual-energy CT angiographies improve assessability of the lower leg arterial segments in peripheral arterial occlusive disease

INTRODUCTION

The aim of this study was to evaluate the influence of a noise optimized virtual monoenergetic reconstruction algorithm (VMI+) on the image quality and assessability of dual energy (DE) computed tomography angiography (CTA) of the lower extremity runoff.

METHODS

A total of 118 lower extremity runoff CTA performed on a 3rd generation DE-CT scanner in 109 patients (54 females; 75.6 ± 9.5 years) were included in this retrospective study. Axial image stacks were reconstructed with a standard 120 kV setting and VMI+ of different keV levels. Objective image quality criteria (contrast attenuation, signal-to-noise [SNR] and contrast-to-noise ratio [CNR]) were measured. Two radiologists evaluated subjective image quality regarding intraluminal attenuation and image noise using a 5-point Likert scale. Diagnostic accuracy for significant stenosis (>75%) and vessel occlusion was assessed for 120 kV and 50 keV VMI+ images rated by two radiologists. In all patients, a digital subtraction angiography (DSA) rated by on board-certified radiologist served as the standard of reference.

RESULTS

Intraluminal attenuation was highest in 40/50 keV VMI+ while SNR were similar to 120 kV images. In subjective assessment, intraluminal contrast of 50 keV images was deemed superior compared to 120 kV despite higher image noise. Sensitivity, specificity, and accuracy for detection of a vessel occlusion were similar in 50 keV VMI+ compared to 120 kV (70%/92%/84%; 70%/91%/83%; p < 0.001) but 13 of 118 (11%) lower leg runoffs were only assessable with 50 keV VMI+.

CONCLUSION

VMI+ reconstructions improve assessability of DE-CTA by increased luminal attenuation with consistent image noise, also allowing the evaluation of lower leg arterial segments inassessable with standard reconstructions.

IMPLICATIONS FOR PRACTICE

Providing higher intraluminal attenuation and similar image noise compared with conventional reconstructions, 50 keV VMI+ may be appropriate for routine evaluation of DE-CTA.

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

BACKGROUND

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Formation and Detection of High-Pressure Oxygen in Closed Pores of La0.6Sr0.4CoO3-δ Solid Oxide Electrolysis Anodes

The chemical capacitance of La_0.6Sr_0.4CoO_3-δ (LSC) thin film microelectrodes with different microstructures was investigated upon varying anodic DC voltages. Dense and porous electrodes (open porosity) were prepared by using different parameters during pulsed laser deposition (PLD). Furthermore, electrodes with closed porosity were fabricated by depositing a dense capping layer on a porous film. Electrochemical impedance spectroscopy (EIS) was performed in synthetic air at 460 and 608 °C with anodic DC voltages up to 440 mV. Chemical capacitance values of the electrodes were derived from the obtained spectra. While the chemical capacitance of dense and porous electrodes decreased as expected with increasing anodic overpotential, electrodes with closed pores exhibited very unusual peaks with extremely high values of >8000 F/cm³ at overpotentials of >100 mV. We demonstrate that this huge capacitance increase agrees very well with calculated chemical capacitances deduced from a real gas equation. Hence, we conclude that the formation of highly pressurized oxygen (up to gas pressures of ∼10⁴ bar) in closed pores is responsible for this strong capacitive effect at anodic overpotentials. Such measurements can thus detect and quantify the buildup of high internal gas pressures in closed pores at the anode side of solid oxide electrolysis cells.

In situ techniques reveal the true capabilities of SOFC cathode materials and their sudden degradation due to omnipresent sulfur trace impurities

In this study, five different mixed conducting cathode materials were grown as dense thin films by pulsed laser deposition (PLD) and characterized via in situ impedance spectroscopy directly after growth inside the PLD chamber (i-PLD). This technique enables quantification of the oxygen reduction kinetics on pristine and contaminant-free mixed conducting surfaces. The measurements reveal excellent catalytic performance of all pristine materials with polarization resistances being up to two orders of magnitude lower than those previously reported in the literature. For instance, on dense La_0.6Sr_0.4CoO_3-δ thin films, an area specific surface resistance of ∼0.2 Ω cm² at 600 °C in synthetic air was found, while values usually >1 Ω cm² are measured in conventional ex situ measurement setups. While surfaces after i-PLD measurements were very clean, ambient pressure X-ray photoelectron spectroscopy (AP-XPS) measurements found that all samples measured in other setups were contaminated with sulfate adsorbates. In situ impedance spectroscopy during AP-XPS revealed that already trace amounts of sulfur present in high purity gases accumulate quickly on pristine surfaces and lead to strongly increased surface polarization resistances, even before the formation of a SrSO₄ secondary phase. Accordingly, the inherent excellent catalytic properties of this important class of materials were often inaccessible so far. As a proof of concept, the fast kinetics observed on sulfate-free surfaces were also realized in ex situ measurements with a gas purification setup and further reduces the sulfur concentration in the high purity gas.

Outer membrane vesicles as carriers for bacterial extracellular ATP modulate local and remote inflammation in peritoneal sepsis

Objective

Adenosine triphosphate (ATP) may be released to the extracellular space and activate specific purinergic receptors to modulate inflammatory responses. In addition to eukaryotes, ATP is also released by bacteria. This bacterial extracellular ATP (eATP) subsequently may act as an inter-kingdom signaling molecule between bacteria and its host. How ATP is secreted by bacteria and its consequences in systemic infection such as sepsis remains unclear. This study aims to determine how ATP is secreted by bacteria and to elucidate its interaction with the host immune system in a model of peritoneal sepsis.

Methods

Bacteria from septic patients were isolated from peritoneal washes. Peritoneal sepsis in mice was induced by cecal ligation and puncture. Peritoneal fluid was collected, (an)aerobically plated and colonies were identified by 16S-sequencing. EATP was periodically measured from bacteria culture supernatant using a luciferin-luciferase assay. Bacteria in culture were counted by plating and the amount of live/dead bacteria was assessed using flow cytometry. To specifically assess the role of bacterial eATP in vivo, E. coli K-12 BW25113 parental strain from the keio collection was used, transformed with a plasmid coding for an apyrase and i.p. injected. Furthermore, a hypervesiculation mutant of this keio collection was used to collect outer membrane vesicles (OMV). These OMV were then loaded with ATP using electroporation and injected i.p in mice.

Results

All bacteria that were isolated from human or mouse peritoneal washes were able to secrete ATP in a growth-phase dependent manner in vitro. In addition to passive release by dying bacteria, we have identified that the amount of eATP is connected with the formation of outer membrane vesicles (OMV) as shown by the E. coliΔtolB hypervesiculation mutant. Whole bacterial eATP led to a significant worse outcome in mice suffering from peritoneal sepsis. In addition, bacterial eATP specifically delivered via OMV worsened septic outcome as well, critically modulating neutrophil recruitment. At the infection site, ATP-loaded OMV led to an impaired recruitment of neutrophils whereas in the lung they led to an elevated infiltration.

Conclusion

OMV serve as a carrier of bacterial wall LPS on its surface as well as bacterial eATP as its content and specifically alter the outcome during sepsis influencing neutrophils locally as well as at remote sites.

Combining electron spin resonance spectroscopy with scanning tunneling microscopy at high magnetic fields

The continuous increase in storage densities and the desire for quantum memories and computers push the limits of magnetic characterization techniques. Ultimately, a tool that is capable of coherently manipulating and detecting individual quantum spins is needed. Scanning tunneling microscopy (STM) is the only technique that unites the prerequisites of high spatial and energy resolution, low temperature, and high magnetic fields to achieve this goal. Limitations in the available frequency range for electron spin resonance STM (ESR-STM) mean that many instruments operate in the thermal noise regime. We resolve challenges in signal delivery to extend the operational frequency range of ESR-STM by more than a factor of two and up to 100 GHz, making the Zeeman energy the dominant energy scale at achievable cryogenic temperatures of a few hundred millikelvin. We present a general method for augmenting existing instruments into ESR-STM to investigate spin dynamics in the high-field limit. We demonstrate the performance of the instrument by analyzing inelastic tunneling in a junction driven by a microwave signal and provide proof of principle measurements for ESR-STM.

T2-weighted MRI defines critical compression in the distal carpal tunnel that is relieved after decompressive surgery

Introduction

Despite Carpal Tunnel Syndrome (CTS) being the most common entrapment neuropathy, its pathophysiology remains debated. Sub-synovial connective tissues (SSCT) within the carpal tunnel are thought to play a role but are poorly characterised. MRI analysis offers potentially novel insights into SSCT characteristics.

Methods

A pilot study of T2-weighted MRI was performed in healthy controls (n=7), and in CTS patients (n=16) pre- and 6 months post-surgical decompression. Image analysis was performed to quantify SSCT cross-sectional area, SSCT signal intensity ratio, and wrist index (depth/width) at distal, middle and proximal wrist landmarks.

Results

Median SSCT signal intensity was lower in the distal carpal tunnel of CTS patients pre-operatively (0.96) compared to controls (1.13; P = 0.008) and normalised post-operatively (1.13, P = 0.001). Median wrist index was also lower in CTS patients pre-operatively (0.60) compared to controls (0.67, P = 0.022), and again normalised post-operatively (0.74, P =0.001). This was attributed to changes in carpal depth in the antero-posterior axis with decompression surgery.

Conclusion

This pilot study successfully demonstrated MRI assessment of SSCT in patients with CTS. The decreased SSCT signal intensities suggest predominant changes at the distal tunnel, potentially indicating reduced SSCT perfusion pre-surgery which normalised post-surgery. Our preliminary findings merit further investigation in a larger cohort.

Investigating oxygen reduction pathways on pristine SOFC cathode surfaces by in situ PLD impedance spectroscopy

The oxygen exchange reaction mechanism on truly pristine surfaces of SOFC cathode materials (La0.6Sr0.4CoO3-δ = LSC, La0.6Sr0.4FeO3-δ = LSF, (La0.6Sr0.4)0.98Pt0.02FeO3-δ = Pt:LSF, SrTi0.3Fe0.7O3-δ = STF, Pr0.1Ce0.9O2-δ = PCO and La0.6Sr0.4MnO3-δ = LSM) was investigated employing in situ impedance spectroscopy during pulsed laser deposition (i-PLD) over a wide temperature and p(O2) range. Besides demonstrating the often astonishing catalytic capabilities of the materials, it is possible to discuss the oxygen exchange reaction mechanism based on experiments on clean surfaces unaltered by external degradation processes. All investigated materials with at least moderate ionic conductivity (i.e. all except LSM) exhibit polarization resistances with very similar p(O2)- and T-dependences, mostly differing only in absolute value. In combination with non-equilibrium measurements under polarization and defect chemical model calculations, these results elucidate several aspects of the oxygen exchange reaction mechanism and refine the understanding of the role oxygen vacancies and electronic charge carriers play in the oxygen exchange reaction. It was found that a major part of the effective activation energy of the surface exchange reaction, which is observed during equilibrium measurements, originates from thermally activated charge carrier concentrations. Electrode polarization was therefore used to control defect concentrations and to extract concentration amended activation energies, which prove to be drastically different for oxygen incorporation and evolution (0.26 vs. 2.05 eV for LSF).

Cation non-stoichiometry in Fe:SrTiO3 thin films and its effect on the electrical conductivity

The interplay of structure, composition and electrical conductivity was investigated for Fe-doped SrTiO₃ thin films prepared by pulsed laser deposition. Structural information was obtained by reciprocal space mapping while solution-based inductively-coupled plasma optical emission spectroscopy and positron annihilation lifetime spectroscopy were employed to reveal the cation composition and the predominant point defects of the thin films, respectively. A severe cation non-stoichiometry with Sr vacancies was found in films deposited from stoichiometric targets. The across plane electrical conductivity of such epitaxial films was studied in the temperature range of 250-720 °C by impedance spectroscopy. This revealed a pseudo-intrinsic electronic conductivity despite the substantial Fe acceptor doping, i.e. conductivities being several orders of magnitude lower than expected. Variation of PLD deposition parameters causes some changes of the cation stoichiometry, but the films still have conductivities much lower than expected. Targets with significant Sr excess (in the range of several percent) were employed to improve the cation stoichiometry in the films. The use of 7% Sr-excess targets resulted in near-stoichiometric films with conductivities close to the stoichiometric bulk counterpart. The measurements show that a fine-tuning of the film stoichiometry is required in order to obtain acceptor doped SrTiO₃ thin films with bulk-like properties. One can conclude that, although reciprocal space maps give a first hint whether or not cation non-stoichiometry is present, conductivity measurements are more appropriate for assessing SrTiO₃ film quality in terms of cation stoichiometry.

CADA: phenotype-driven gene prioritization based on a case-enriched knowledge graph

Many rare syndromes can be well described and delineated from other disorders by a combination of characteristic symptoms. These phenotypic features are best documented with terms of the Human Phenotype Ontology (HPO), which are increasingly used in electronic health records (EHRs), too. Many algorithms that perform HPO-based gene prioritization have also been developed; however, the performance of many such tools suffers from an over-representation of atypical cases in the medical literature. This is certainly the case if the algorithm cannot handle features that occur with reduced frequency in a disorder. With Cada, we built a knowledge graph based on both case annotations and disorder annotations. Using network representation learning, we achieve gene prioritization by link prediction. Our results suggest that Cada exhibits superior performance particularly for patients that present with the pathognomonic findings of a disease. Additionally, information about the frequency of occurrence of a feature can readily be incorporated, when available. Crucial in the design of our approach is the use of the growing amount of phenotype–genotype information that diagnostic labs deposit in databases such as ClinVar. By this means, Cada is an ideal reference tool for differential diagnostics in rare disorders that can also be updated regularly.

Heat flows in rock cracks naturally optimize salt compositions for ribozymes

Catalytic nucleic acids, such as ribozymes, are central to a variety of origin-of-life scenarios. Typically, they require elevated magnesium concentrations for folding and activity, but their function can be inhibited by high concentrations of monovalent salts. Here we show that geologically plausible high-sodium, low-magnesium solutions derived from leaching basalt (rock and remelted glass) inhibit ribozyme catalysis, but that this activity can be rescued by selective magnesium up-concentration by heat flow across rock fissures. In contrast to up-concentration by dehydration or freezing, this system is so far from equilibrium that it can actively alter the Mg:Na salt ratio to an extent that enables key ribozyme activities, such as self-replication and RNA extension, in otherwise challenging solution conditions. The principle demonstrated here is applicable to a broad range of salt concentrations and compositions, and, as such, highly relevant to various origin-of-life scenarios.

Sensorimotor and body perception assessments of nonspecific chronic low back pain: a cross-sectional study

BACKGROUND

Low back pain (LBP) is one of the most common musculoskeletal disorders, causing significant personal and social burden. Current research is focused on the processes of the central nervous system (particularly the sensorimotor system) and body perception, with a view to developing new and more efficient ways to treat chronic low back pain (CLBP). Several clinical tests have been suggested that might have the ability to detect alterations in the sensorimotor system. These include back-photo assessment (BPA), two-point discrimination (TPD), and the movement control tests (MCT). The aim of this study was to determine whether the simple clinical tests of BPA, TPD or MCT are able to discriminate between nonspecific CLBP subjects with altered body perception and healthy controls.

METHODS

A cross-sectional study was conducted. At one point in time, 30 subjects with CLBP and 30 healthy controls were investigated through using BPA, TPD and MCT on the lower back. Correlations among the main covariates and odds ratios for group differences were calculated.

RESULTS

MCT showed an odds ratio for the presence of CLBP of 1.92, with a statistically significant p-value (0.049) and 95%CI. The TPD and BPA tests were unable to determine significant differences between the groups.

CONCLUSIONS

Of the three tests investigated, MCT was found to be the only suitable assessment to discriminate between nonspecific CLBP subjects and healthy controls. The MCT can be recommended as a simple clinical tool to detect alterations in the sensorimotor system of nonspecific CLBP subjects. This could facilitate the development of tailored management strategies for this challenging LBP subgroup. However, further research is necessary to elucidate the potential of all the tests to detect alterations in the sensorimotor system of CLBP subjects.

TRIAL REGISTRATION

No trial registration was needed as the study contains no intervention. The study was approved by the Swiss Ethics Commission of Northwest and Central Switzerland (EKNZ) reference number 2015-243.

Narrative review of metabolomics in cardiovascular disease

Cardiovascular diseases are accompanied by disorders in the cardiac metabolism. Furthermore, comorbidities often associated with cardiovascular disease can alter systemic and myocardial metabolism contributing to worsening of cardiac performance and health status. Biomarkers such as natriuretic peptides or troponins already support diagnosis, prognosis and treatment of patients with cardiovascular diseases and are represented in international guidelines. However, as cardiovascular diseases affect various pathophysiological pathways, a single biomarker approach cannot be regarded as ideal to reveal optimal clinical application. Emerging metabolomics technology allows the measurement of hundreds of metabolites in biological fluids or biopsies and thus to characterize each patient by its own metabolic fingerprint, improving our understanding of complex diseases, significantly altering the management of cardiovascular diseases and possibly personalizing medicine. This review outlines current knowledge, perspectives as well as limitations of metabolomics for diagnosis, prognosis and treatment of cardiovascular diseases such as heart failure, atherosclerosis, ischemic and non-ischemic cardiomyopathy. Furthermore, an ongoing research project tackling current inconsistencies as well as clinical applications of metabolomics will be discussed. Taken together, the application of metabolomics will enable us to gain more insights into pathophysiological interactions of metabolites and disease states as well as improving therapies of patients with cardiovascular diseases in the future.

Effect of long term CPAP therapy on cardiac parameters assessed with cardiac MRI

The obstructive sleep apnoea syndrome (OSAS) is a disorder with a high prevalence and is associated with an elevated cardiovascular risk and increased morbidity and mortality. For longitudinal studies and functional analysis cardiac MRI is regarded as the gold standard. Aim of this study was to evaluate the long-term effect of continuous positive airway pressure (CPAP) therapy on cardiac functional parameters with cardiac Magnetic Resonance Imaging (cMRI). 54 patients with OSAS (mean apnea hypopnea index-AHI: 31) were prospectively enrolled in this study and cMRI was performed before and after 7 months of CPAP therapy. Data were acquired on a 1.5 T MRI and right and left ventricular cardiac function were analysed. CPAP treatment was considered compliant when used ≥ 4 h per night. 24-h blood pressure was measured at baseline and follow up. 33 patients could be assigned to the compliance group. Left ventricular stroke volume (LV SV) and right ventricular ejection fraction (RV EF) improved significantly with CPAP therapy (LV SV from 93 ± 19 to 99 ± 20 ml, p = 0.02; RV EF from 50 ± 6 to 52 ± 6%, p = 0.04). All other cardiac parameters did not change significantly while mean systolic and diastolic blood pressure improved significantly (p < 0.01). 21 patients were assigned to the non-compliance group and were considered as a control group. There were no relevant differences in cardiac parameters between baseline and follow up examination in these patients. CPAP therapy seems to improve LV SV, RV EF, systolic and diastolic blood pressure in OSAS patients, but reproducibility of our results need to be confirmed in a larger patient population.

SAT0135 COMPARISON OF THE EFFICACY AND SAFETY OF TWO BRIDGING SCHEDULES OF PREDNISOLONE IN EARLY ACTIVE RHEUMATOID ARTHRITIS (CORRA): A DOUBLE-BLIND, RANDOMISED, PLACEBO-CONTROLLED TRIAL

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease potentially leading to disability, impaired functioning, and premature death. Most treatment strategies include the early use of disease-modifying antirheumatic drugs (DMARDs) such as methotrexate (MTX) which is considered as an established ‘anchor’ therapy. Since it takes some weeks until MTX shows clinical efficacy, glucocorticoids (GC) are widely used for bridging.

Objectives:

The aim of the study “Comparison of the efficacy and safety of two starting dosages of prednisolone in early active RA” (CORRA) is to compare the efficacy and safety of two standard GC bridging schedules vs. placebo in addition to MTX, following a treat-to-target regimen, in early RA.

Methods:

CORRA is an investigator-initiated, randomised, multi-center, double-blind, placebo-controlled trial. Adult RA patients who were eligible for inclusion in the trial if they had a disease duration of less than 3 years and moderate or high disease activity were recruited in one hospital and 18 rheumatology practices in Germany. Patients were randomised (1:1:1) to receive 60 mg or 10 mg prednisolone (Pred) orally once daily (tapered down to 5 mg Pred within 8 weeks) or placebo. The duration of the intervention was 12 weeks, followed by an open observational phase for another 40 weeks. All patients were also treated with MTX (usually starting with 15mg/week followed by a treat-to target scheme). The primary efficacy endpoint was the progression of the radiographic joint damage after one year compared to baseline as determined by the van der Heijde modification of the Sharp score (SHS). Patients, physicians and readers of radiographs were unaware of the treatment assignments. For the comparison of the two GC groups, a non-inferiority margin of 1.3 points of the SHS was set. This trial was registered at ClinicalTrials.gov, numberNCT02000336.

Results:

Between February 2014 and February 2017, 395 patients were included in the trial, 381 of which had sufficient data also of follow-up visits. A total of 129 patients were assigned to the 60 mg Pred group, 124 to 10 mg Pred and 128 to the placebo group. At baseline, mean age was 58 years, 58% were female, 55% were rheumatoid factor and 52% ACPA positive. The mean number of swollen joints was 12.8 out of 28, mean ESR was 33.6 mm/h, mean CRP 2.2 mg/dL, mean DAS 28 6.0. Radiographic damage was 4.9 as measured by the SHS. In the 60 mg, 10 mg Pred group and in the placebo group, the DAS 28 was 2.6, 3.1, 4.5 at week 4 (p<0.001), 3.1, 2.8, 3.6 at week 12 (p<0.001), and 2.7, 2.6, 2.8 at week 52 (p=0.411), respectively. After 12 months the radiographic progression could be determined in 375 patients. In the 60 mg, 10 mg Pred group, and in the placebo group, the mean progression after 1 year was 1.0, 1.0, 1.1 for the total SHS and 0.5, 0.6, 0.7 for the erosion score of the SHS, respectively. Statistical analysis showed non-inferiority of the 10 mg Pred and of the placebo group in comparison to the 60 mg Pred group. Regarding safety issues, there were 10, 5, 6 serious adverse events and 31, 16, 20 adverse events in the MedDRA system organ class “infections and infestations” for the 60 mg Pred, 10 mg Pred, and the placebo group, respectively.

Conclusion:

The bridging schedule starting with 60 mg Pred reduced disease activity better than the 10 mg schedule or placebo only for a short time. The primary outcome structural damage was non-inferior in the 10 mg Pred and the placebo group in comparison to the 60 mg Pred group. Initial advantages of the higher dose may have been compromised by the long follow-up with the possible escalation of therapy due to the treat-to-target regimen.

Disclosure of Interests:

Dietmar Krause Grant/research support from: Pfizer and AbbVie (Abbott), Anna Mai: None declared, Nina Timmesfeld: None declared, Ulrike Trampisch: None declared, Renate Klaassen-Mielke: None declared, Henrik Rudolf: None declared, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Elmar Schmitz: None declared, Claas Fendler: None declared, Claudia Klink: None declared, Stephanie Boeddeker: None declared, Ertan Saracbasi: None declared, Jochen Christoph: None declared, Manfred Igelmann: None declared, Hans Juergen Menne: None declared, Albert Schmid: None declared, Hans J Trampisch: None declared, Juergen Braun Grant/research support from: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Eli Lilly and Company, Medac, MSD (Schering Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi- Aventis, and UCB Pharma, Consultant of: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma, Speakers bureau: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma

Bevacizumab plus hypofractionated radiotherapy versus radiotherapy alone in elderly patients with glioblastoma: the randomized, open-label, phase II ARTE trial

Background

The addition of bevacizumab to temozolomide-based chemoradiotherapy (TMZ/RT → TMZ) did not prolong overall survival (OS) in patients with newly diagnosed glioblastoma in phase III trials. Elderly and frail patients are underrepresented in clinical trials, but early reports suggested preferential benefit in this population.

Patients and methods

ARTE was a 2 : 1 randomized, multi-center, open-label, non-comparative phase II trial of hypofractionated RT (40 Gy in 15 fractions) with bevacizumab (10 mg/kg×14 days) (arm A, N = 50) or without bevacizumab (arm B, N = 25) in patients with newly diagnosed glioblastoma aged ≥65 years. The primary objective was to obtain evidence for prolongation of median OS by the addition of bevacizumab to RT. Response was assessed by RANO criteria. Quality of life (QoL) was monitored by the EORTC QLQ-C30/BN20 modules. Exploratory studies included molecular subtyping by 450k whole methylome and gene expression analyses.

Results

Median PFS was longer in arm A than in arm B (7.6 and 4.8 months, P = 0.003), but OS was similar (12.1 and 12.2 months, P = 0.77). Clinical deterioration was delayed and more patients came off steroids in arm A. Prolonged PFS in arm A was confined to tumors with the receptor tyrosine kinase (RTK) I methylation subtype (HR 0.25, P = 0.014) and proneural gene expression (HR 0.29, P = 0.025). In a Cox model of OS controlling for established prognostic factors, associations with more favorable outcome were identified for age <70 years (HR 0.52, P = 0.018) and Karnofsky performance score 90%-100% (HR 0.51, P = 0.026). Including molecular subtypes into that model identified an association of the RTK II gene methylation subtype with inferior OS (HR 1.73, P = 0.076).

Conclusion

Efficacy outcomes and exploratory analyses of ARTE do not support the hypothesis that the addition of bevacizumab to RT generally prolongs survival in elderly glioblastoma patients. Molecular biomarkers may identify patients with preferential benefit from bevacizumab.

Clinical trial registration number

NCT01443676.

Consensus in determining the resectability of locally progressed pancreatic ductal adenocarcinoma - results of the Conko-007 multicenter trial

Background

One critical step in the therapy of patients with localized pancreatic cancer is the determination of local resectability. The decision between primary surgery versus upfront local or systemic cancer therapy seems especially to differ between pancreatic cancer centers. In our cohort study, we analyzed the independent judgement of resectability of five experienced high volume pancreatic surgeons in 200 consecutive patients with borderline resectable or locally advanced pancreatic cancer.

Methods

Pretherapeutic CT or MRI scans of 200 consecutive patients with borderline resectable or locally advanced pancreatic cancer were evaluated by 5 independent pancreatic surgeons. Resectability and the degree of abutment of the tumor to the venous and arterial structures adjacent to the pancreas were reported. Interrater reliability and dispersion indices were compared.

Results

One hundred ninety-four CT scans and 6 MRI scans were evaluated and all parameters were evaluated by all surgeons in 133 (66.5%) cases. Low agreement was observed for tumor infiltration of venous structures (κ = 0.265 and κ = 0.285) while good agreement was achieved for the abutment of the tumor to arterial structures (interrater reliability celiac trunk κ = 0.708 P < 0.001). In patients with vascular tumor contact indicating locally advanced disease, surgeons highly agreed on unresectability, but in patients with vascular tumor abutment consistent with borderline resectable disease, the judgement of resectability was less uniform (dispersion index locally advanced vs. borderline resectable p < 0.05).

Conclusion

Excellent agreement between surgeons exists in determining the presence of arterial abutment and locally advanced pancreatic cancer. The determination of resectability in borderline resectable patients is influenced by additional subjective factors.

Trial registration

EudraCT:2009-014476-21 (2013-02-22) and NCT01827553 (2013-04-09).

How To Get Mechanistic Information from Partial Pressure-Dependent Current-Voltage Measurements of Oxygen Exchange on Mixed Conducting Electrodes

The oxygen incorporation and evolution reaction on mixed conducting electrodes of solid oxide fuel or electrolysis cells involves gas molecules as well as ionic and electronic point defects in the electrode. The defect concentrations depend on the gas phase and can be modified by the overpotential. These interrelationships make a mechanistic analysis of partial pressure-dependent current-voltage experiments challenging. In this contribution it is described how to exploit this complex situation to unravel the kinetic roles of surface adsorbates and electrode point defects. Essential is a counterbalancing of oxygen partial pressure and dc electrode polarization such that the point defect concentrations in the electrode remain constant despite varying the oxygen partial pressure. It is exemplarily shown for La_0.6Sr_0.4FeO_3-δ (LSF) thin film electrodes on yttria-stabilized zirconia how mechanistically relevant reaction orders can be obtained from current-voltage curves, measured in a three-electrode setup. This analysis strongly suggests electron holes as the limiting defect species for the oxygen evolution on LSF and reveals the dependence of the oxygen incorporation rate on the oxygen vacancy concentration. A virtual independence of the reaction rate from the oxygen partial pressure was empirically found for moderate oxygen pressures. This effect, however, arises from a counterbalancing of defect and adsorbate concentration changes.

Voltage and partial pressure dependent defect chemistry in (La,Sr)FeO3-δ thin films investigated by chemical capacitance measurements

Chemical capacitance measurements are used to study the defect chemistry of La_0.6Sr_0.4FeO_3–δ thin films and their polarization (η) and p_O2 dependence. Important point defects are oxygen vacancies (), electrons (e′) and holes (h˙).

La_0.6Sr_0.4FeO_3–δ (LSF) thin films of different thickness were prepared by pulsed laser deposition on yttria stabilized zirconia (YSZ) and characterized by using three electrode impedance spectroscopy. Electrochemical film capacitance was analyzed in relation to oxygen partial pressure (0.25 mbar to 1 bar), DC polarization (0 m to –600 m) and temperature (500 to 650 °C). For most measurement parameters, the chemical bulk capacitance dominates the overall capacitive properties and the corresponding defect chemical state depends solely on the oxygen chemical potential inside the film, independent of atmospheric oxygen pressure and DC polarization. Thus, defect chemical properties (defect concentrations and defect formation enthalpies) could be deduced from such measurements. Comparison with LSF defect chemical bulk data from the literature showed good agreement for vacancy formation energies but suggested larger electronic defect concentrations in the films. From thickness-dependent measurements at lower oxygen chemical potentials, an additional capacitive contribution could be identified and attributed to the LSF|YSZ interface. Deviations from simple chemical capacitance models at high pressures are most probably due to defect interactions.

Lightweight, Room-Temperature CO2 Gas Sensor Based on Rare-Earth Metal-Free Composites-An Impedance Study

We report a light, flexible, and low-power poly(ionic liquid)/alumina composite CO2 sensor. We monitor the direct-current resistance changes as a function of CO2 concentration and relative humidity and demonstrate fast and reversible sensing kinetics. Moreover, on the basis of the alternating-current impedance measurements we propose a sensing mechanism related to proton conduction and gas diffusion. The findings presented herein will promote the development of organic/inorganic composite CO2 gas sensors. In the future, such sensors will be useful for numerous practical applications ranging from indoor air quality control to the monitoring of manufacturing processes.

Telemedically Supported Case Management of Living-Donor Renal Transplant Recipients to Optimize Routine Evidence-Based Aftercare: A Single-Center Randomized Controlled Trial

Improving mid-term and long-term outcomes after solid organ transplantation is imperative, and requires both state-of-the-art transplant surgery and optimization of routine, evidence-based aftercare. This randomized, controlled trial assessed the effectiveness of standard aftercare versus telemedically supported case management, an innovative aftercare model, in 46 living-donor renal transplant recipients during the first posttransplant year. The model includes three components: (i) chronic care case management initiated after discharge, (ii) case management initiated in emerging acute care situations, and (iii) a telemedically equipped team comprising a transplant nurse case manager and two senior transplant physicians (nephrologist, surgeon). Analyses revealed a reduction of unplanned inpatient acute care, with considerable cost reductions, in the intervention group. The prevalence of nonadherence over the 1-year study period was 17.4% in the intervention group versus 56.5% in the standard aftercare group (p = 0.013). Only the intervention group achieved their pre-agreed levels of adherence, disease-specific quality of life, and return to employment. This comparative effectiveness study provides the basis for multicenter study testing of telemedically supported case management with the aim of optimizing posttransplant aftercare. The trial was registered with the German Clinical Trials Register (www.DRKS.de), DKRS00007634.

The Chemical Capacitance as a Fingerprint of Defect Chemistry in Mixed Conducting Oxides

The oxygen stoichiometry of mixed conducting oxides depends on the oxygen chemical potential and thus on the oxygen partial pressure in the gas phase. Also voltages may change the local oxygen stoichiometry and the amount to which such changes take place is quantified by the chemical capacitance of the sample. Impedance spectroscopy can be used to probe this chemical capacitance. Impedance measurements on different oxides ((La,Sr)FeO3-δ = LSF, Sr(Ti,Fe)O3-δ = STF, and Pb(Zr,Ti)O3 = PZT) are presented, and demonstrate how the chemical capacitance may affect impedance spectra in different types of electrochemical cells. A quantitative analysis of the spectra is based on generalized equivalent circuits developed for mixed conducting oxides by J. Jamnik and J. Maier. It is discussed how defect chemical information can be deduced from the chemical capacitance.

Short-Term Regulation of Lipocalin-2 but not RBP-4 During Oral Lipid Tolerance Test and Oral Glucose Tolerance Test

The postprandial regulation of lipocalin-2 and retinol binding protein-4 (RBP-4) by oral uptake of lipids and carbohydrates in healthy individuals has not yet been investigated. The regulation of lipocalin-2 and RBP-4 in 2 large cohorts of healthy volunteers during oral lipid tolerance test (OLTT; n=100) and oral glucose tolerance test (OGTT; n=100) was analyzed. One hundred healthy volunteers underwent OLTT and OGTT in an outpatient setting. Venous blood was drawn after 0, 2, 4, and 6 h in OLTT and after 0, 1, and 2 h in OGTT. In order to dissect carbohydrate-induced from lipid-induced effects, a novel OLTT solution completely free of carbohydrates and protein was applied. Subjects were characterized by anthropometric and laboratory parameters. Serum concentrations of lipocalin-2 and RBP-4 were measured by enzyme-linked immunosorbent assay (ELISA). Whereas RBP-4 levels remained unchanged during OGTT, lipocalin-2 concentrations significantly decreased during OGTT. During OLTT, RBP-4 levels were not influenced, whereas lipocalin-2 levels decreased significantly and stepwise. Fasting concentrations of RBP-4 were negatively correlated with BMI and waist-hip ratio, whereas lipocalin-2 levels were positively associated with BMI and waist-hip ratio. Female users of hormonal contraception had higher RBP-4 levels than females not on contraceptives. There is no significant short-term regulation of RBP-4 by orally ingested lipids or carbohydrates. Lipocalin-2 is downregulated after lipid and carbohydrate ingestion and this kind of regulation was not predicted by age, sex, triglycerides, glucose, or insulin levels.

Flemish obstetricians' personal preference regarding induction of labor and mode of delivery in term births

INTRODUCTION

In a 2002 survey, 2% of Flemish gynecologists preferred elective cesarean section for themselves or their partner. This study aims to determine actual preference regarding induction of labor and mode of delivery in term cephalic or breech births for gy- necologists or their partners.

MATERIALS AND METHODS

An anonymous postal questionnaire was sent to all gynecologists and trainees in Flanders.

RESULTS

Response rate was 28.2 % (241/852). In case of an uncomplicated cephalic singleton pregnancy, 39 gynecologists (16.2%) preferred cesarean section. Most (n=134, 66.5%) chose induction at 41 weeks, 26 (13%) at 40 weeks, 37 (18%) at 42 weeks, 26 (13%) at 40 weeks, three (1.5%) preferred induction before 40 weeks and two (1%) would wait until after 42 weeks. Concerning term breech, 30% (n=72) opted for vaginal delivery and 70% (n = 169) for planned cesarean section. Ninety-nine (41%) gynecologists pre- ferred to attempt external version first. Only 115 (47.7 %) gynecologists felt professionally capable to assist vaginal breech delivery them- selves; about one-third (n=96; 38%) had performed less than ten vaginal breech deliveries in their career.

CONCLUSIONS

Flemish gynecologists are still in favor of vaginal delivery for themselves in terms of cephalic position, but an increasing number favor planned cesarean section. Most Flemish gynecologists opt for cesarean section for themselves or their partners in case of term breech and state that they do not feel capable in assisting vaginal breech delivery for their patients.

Serum progranulin concentrations are not responsive during oral lipid tolerance test and oral glucose tolerance test

The postprandial regulation of progranulin by oral uptake of lipids and carbohydrates in healthy individuals has not yet been investigated. The regulation of progranulin in 2 large cohorts of healthy volunteers during oral lipid tolerance test (OLTT; n=100) and oral glucose tolerance test (OGTT; n=100) was analyzed. One hundred healthy volunteers underwent OLTT and OGTT in an outpatient setting. Venous blood was drawn at 0 hours (h) (fasting) and at 2, 4, and 6 h in OLTT or 1 and 2 h in OGTT. A novel OLTT solution completely free of carbohydrates and protein was applied. Subjects were characterized by anthropometric and laboratory parameters. Serum concentrations of progranulin were measured by enzyme-linked immunosorbent assay (ELISA). Circulating progranulin levels remained unchanged during OLTT and OGTT. Fasting progranulin levels ranged between 31.3±8.7 and 40.6±7.7 ng/ml and were not different in subgroups addressing BMI, gender, family history, smoking habits, and hormonal contraception. There was a reciprocal correlation of progranulin with HDL (negative) and LDL cholesterol levels (positive). In healthy adults, fasting and postprandial circulating progranulin levels are not different in BMI subgroups. Oral uptake of carbohydrates and lipids does not influence circulating progranulin levels in a short-term manner. A postprandial and short-term regulation of this adipokine is absent, at least in healthy subjects. There is a negative correlation of progranulin with HDL cholesterol, but a positive correlation with LDL cholesterol. This reciprocal association might be of physiological importance for an individual's atherosclerotic risk.

Cardiomyopathy in Duchenne Muscular Dystrophy: Current Value of Clinical, Electrophysiological and Imaging Findings in Children and Teenagers

BACKGROUND

Progressive cardiomyopathy (CMP) is one main cause of death in DMD. This cross-sectional assessment of different cardiac diagnostic procedures focusses on preterm diagnosis of cardiac dysfunction.

PATIENTS

39 male DMD patients aged 6-20 years were included. 6 patients were still ambulatory, 21 patients received corticosteroid therapy.

METHODS

All patients were investigated by ECG, Holter ECG and heart rate variability (HRV), B-type natriuretic peptide (BNP), echocardiography (TTE), tissue Doppler Imaging (TD) and magnetic resonance imaging (MRI) with Late Gadolinium enhancement (LE) and segmental wall motion analysis (WMA).

RESULTS

56% of the patients showed repolarization abnormalities and 76% altered HRV. Subnormal ventricular function was found in 25% by TTE and in 34% by MRI. TD differed from normal controls only in the apical septum. In MRI 89% of the patients showed different distribution and intensity of LE and WM restriction. The extent of LE was less in patients after steroid treatment (p<0.05).

DISCUSSION

MRI with segmental LE- and WM-analysis seems to be superior to TTE and TD in exploring regional distribution and severity of damage of the myocardium. ECG and HRV abnormalities are common in DMD-patients but not tightly predictive for segmental and global left ventricular dysfunction. Targeted treatment of CMP in DMD needs prospective evaluation.

CONCLUSION

A timely cardiac MRI is the most sensitive investigation for the identification of early myocardial changes in DMD which is a prerequisite for early interventions and therapeutic strategies.