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Electrospun Polymeric Composite Fibers Containing Te-Doped Bioactive Glass Powders
Get PDFIn this work, the electrospinning technique was used to prepare novel polymeric composite fibers containing Te-doped bioactive glass powders. Bioactive glass powders containing tellurium (STe5 glass) were chosen as fillers for the composites, owing to their bioactive, antibacterial, and antioxidant properties. The biopolymer poly (ϵ-caprolactone) (PCL) and acetic acid (AA) were used as raw materials for the preparation of the polymeric matrix. FESEM analysis confirmed a good incorporation of the glass powders in the polymeric fibers, of up to 20% by weight. Wettability, mechanical, in vitro stability and preliminary antibacterial tests were also performed. The results showed that the treatment in AA did not affect the bioactivity of the glass powders, the presence of STe5 powders in PCL enhanced the wettability of the fibers, and mechanical properties improved by increasing the amount of STe5 powders, as well as the antibacterial effect. Therefore, the obtained materials appear promising for developing multifunctional composite materials for applications in tissue engineering.This research received no external funding
Patient experiences, attitudes, and profiles regarding artificial intelligence in rheumatology: a German national cross-sectional survey study
No full textWhile artificial intelligence (AI) is gaining attention in rheumatology, little is known about patient perspectives. This study addresses this gap by examining patients’ experiences and attitudes toward AI. A nationwide, cross-sectional, web-based survey was conducted between March and May 2025 among adult patients with rheumatic diseases in Germany. Data were analyzed descriptively and with cluster analysis. A total of 778 patients completed the survey (70.4% female, mean age 51.3 years). The most common diagnosis was rheumatoid arthritis (31.7%). While 26.8% reported current AI use for health-related purposes, 57.8% expressed interest in using it. Patients were particularly interested in AI-based symptom checkers (64.3%), therapy recommendations (50.6%), and chatbots for medical inquiries (44.5%). 57.6% of patients indicated that they would welcome their rheumatologists using AI-based clinical suppport. The most frequently cited benefits of AI included improved information access (63.5%) and faster diagnosis (57.7%), while concerns centered on faulty AI (74.3%) and reduced human interaction (59.6%). Cluster analysis identified three distinct patient profiles: ‘AI-savvy’ (41.4%), ‘AI-pragmatic’ (44.8%), and ‘AI-skeptical’ (13.8%). Cluster membership was significantly associated with age and education, with younger patients more often belonging to the ‘AI-savvy’ group. Patients with rheumatic diseases showed substantial interest in AI-supported care, although actual use in medical contexts remained limited. Age and education differences highlight the need for tailored implementation strategies to ensure equitable and patient-centered adoption of AI in rheumatology.Open Access funding enabled and organized by Projekt DEAL.Philipps-Universität Marburg (1009
Quantitative terbium-161 SPECT/CT imaging: demonstrating the feasibility of image-based dosimetry and highlighting pitfalls
No full textBackground Terbium-161 ( 161 Tb) is a promising β⁻-emitter for theragnostics. However, its complex photon emission pattern—including intense X-rays and low-yield, high-energy γ-emissions—may complicate image-based quantification. This study aimed to assess the feasibility of accurate SPECT/CT-based 161 Tb dosimetry through a series of phantom measurements using a GE Discovery NM/CT 670 Pro system. Three collimators were evaluated: extended low-energy general-purpose (ELEGP), low-energy high-resolution (LEHR), and medium-energy general-purpose (MEGP), using two separate energy windows: around the 75 keV γ-peak (± 10%), and around the 49 keV γ-peak and nearby X-rays (40.7–62.9 keV). A clinical OSEM reconstruction algorithm was employed. Results On average, the SPECT calibration factors (CFs) were 2-fold higher with ELEGP compared to MEGP and LEHR, and 3-fold higher at 49 keV compared to 75 keV. For each collimator, derived CFs varied substantially depending on measurement and volume-of-interest geometry—more so at 49 keV, compared to 75 keV. Measurements of two 3D-printed kidney inserts revealed superior visual image quality with LEHR compared to ELEGP and MEGP. Across all collimators, the 75 keV window provided better spatial resolution and contrast than the 49 keV window. An anthropomorphic phantom study, including a LungSpine phantom with 8 spherical inserts and 3 different background activity levels, demonstrated a greater quantitative accuracy for MEGP compared to LEHR and ELEGP, with statistical significance for both energy windows ( p ≤ 0.001). Errors were generally larger at 49 keV compared to 75 keV. For the low-energy collimators, considerable septal penetration (e.g., at 292 and 475 keV) was observed, along with systematic underestimation at high activity levels. Conclusions This study demonstrates that highly accurate SPECT/CT-based 161 Tb quantification is feasible, further cementing 161 Tb as a viable theragnostic alternative. A MEGP collimator, a 75 keV window, and a CF derived from a homogeneous cylinder measurement appears preferable. The 49 keV window could be useful at late imaging time points, given its high sensitivity, if further optimized. Degradation from penetration and subsequent downscatter may be mitigated with a more refined reconstruction. Further investigations into dead-time effects are encouraged.Open access funding provided by University of Gothenburg.University of Gothenbur
Methanol-to-electricity via low-temperature steam reforming integrated with a high-temperature PEM fuel cell
No full textLiquid organic hydrogen carriers (LOHCs) are a promising method for renewable, green hydrogen transportation from the point of generation using renewable energy to the point of demand. Methanol is one such LOHC with advantages such as high hydrogen content, easy transportation and a simple reaction to release the hydrogen. Herein, we reported the use of a novel supported liquid phase (SLP) catalyst in a miniplant to carry out low-temperature methanol steam reforming (MSR) to release hydrogen and subsequently produce electricity using a high-temperature proton exchange membrane fuel cell (HT-PEMFC). This reformed methanol fuel cell (RMFC) setup successfully ran over the course of 45 h experiencing little catalyst deactivation, producing up to 49.2 lN h−1 of hydrogen and up to 39 W electrical power using HT-PEMFC. Comparing between the reformate gas produced using SLP catalyst and pure hydrogen as feed for the fuel cell, the HT-PEMFC showed almost no difference in the voltage–current characteristic curve in the technically relevant operating points between 500 and 700 mV cell voltage. Furthermore, a pinch analysis indicated that the combination of a low-temperature MSR and HT-PEMFC presents an opportunity for heat-integration which could lead to increased efficiency.Methanol reforming is carried out at ultra-low temperatures around 423 K catalyzed by supported liquid phase molecular Pu-pincer catalysts (Ru-SLP). The formed hydrogen is directly fed to a HTPEM fuel cell to demonstrate the feasibility.Sasol 10.13039/50110000429
Serum and CSF cytokine profile in patients with facial palsy (Bell’s palsy): a pilot study
No full textBackground and purpose Facial nerve palsy is the most common cranial nerve disorder, and over 60% are idiopathic (Bell’s palsy, BP). An inflammatory process is discussed as a causative factor. The aim of this study was to search for changes in various cytokine concentrations in serum and cerebrospinal fluid (CSF) in patients with facial nerve palsy. Methods In this prospective study, 47 patients with peripheral facial nerve palsy were included. Of these, 40 patients were diagnosed as BP and seven patients as non-idiopathic peripheral facial palsy (nipFP). Seventeen cytokines, including IL-1A, IL-5, IL-9, granulocyte colony-stimulating factor (G-CSF), CXCL-13, granulocyte–macrophage-colony-stimulating factor (GM-CSF), tumor necrosis factor-SF13 (TNFSF13), IL-8, IL-1ß, CXCL-10, fractalkine (Fract), monocyte chemotactic protein (MCP-1), IFN-y, IL-4, IL-17A, tumor necrosis factor (TNF), and Granzyme, were measured in the serum and CSF. For comparison, sera from 10 healthy individuals were used. Results In serum, the levels of cytokines G-CSF, CXCL13, TNFSF13, and Granzyme were statistically significantly higher in patients with BP and nipFP compared to healthy individuals ( p < 0.05). Cytokine IL-1ß was significantly higher in nipFP patients compared to healthy individuals and patients with BP ( p < 0.05). Cytokine IL-8 was significantly lower in both patient groups than in healthy individuals ( p < 0.05). In CSF, G-CSF, CXCL13, TNFSF13, IL-8, IL-1ß, and IL-17A were statistically significantly higher in patients with nipFP compared to patients with BP ( p < 0.05). In addition, patients with BP also showed a clustering of cytokine elevation. For differentiating nipFP from BP, serum G-CSF and IL1ß indicated a certain discrimination (AUC 0.643; 0.614). Patients with severe facial palsy revealed higher CSF TNFSF13 ( p = 0.02), and clinical outcome after 3 months was less favorable at higher CSF Fractalkine ( p = 0.025). Elevated CSF cell count was associated with elevated CXCL13, IL-8, IL-1ß, IP-10, IFNa and granzyme in the CSF ( r = 0.32–0.57; p < 0.05). Conclusion Compared to healthy individuals, our study revealed an altered cytokine profile in patients with BP that resembles patients with nipFP. In CSF, a subset of cytokines was identified in patients with BP, but higher levels were found in patients with nipFP, suggesting a graduated inflammatory process. Study registration The study "Serum and CSF cytokine profile in patients with facial palsy (Bell´s palsy)" has been officially registered at the German Clinical Trials Register (DRKS00037815).Open Access funding enabled and organized by Projekt DEAL.Universitätsklinikum Erlangen (8546
Direct investigation of localized leakage currents in GaN-on-sapphire pn-diodes
No full textThe reliability and robustness of GaN devices continues to suffer from the influence of high dislocation densities. Our group has previously linked dislocations with current leakage paths. In this study, we investigated the localized electroluminescence (EL) signals of these leakage paths in reverse biased GaN pn-diodes grown on a sapphire substrate for their electrical and structural properties. We show that EL signal correlated leakage currents can be modeled by trap-assisted-tunneling (TAT) through segregated impurities at a dislocation. Leakage currents in devices without these leakage paths can be modeled by the Poole-Frenkel (PF) and phonon-assisted-tunneling (PAT) mechanisms. Additionally, we show that this reverse bias leakage, that has historically been attributed to specific dislocation types, cannot be attributed to a specific Burgers vector type.Federal Ministry for Economic Affairs and Climate Action of GermanyECSEL JU through the European Union’s Horizon 2020 Research and Innovation Progra
Flying blind? Recommendations for monitoring of 10 common chronic diseases in guidelines from Germany, England, and Europe — a modified systematic review
No full textBackground Clinical practice guidelines (CPGs) synthesize evidence to recommend which measures should or should not be taken in specific medical situations and thereby inform and shape the practice of medicine. In the context of an ageing population, monitoring has become an increasingly resource-intensive practice, underscoring the need for clear, evidence-based guidance. Accordingly, this study aimed to investigate the level of detail as well as the level of evidence of recommendations on monitoring for 10 common chronic diseases in CPGs from the Association of the Scientific Medical Societies in Germany (AWMF ) , the National Institute for Health and Care Excellence (NICE), and European medical societies. Methods Using a modified systematic review approach, a search of the relevant CPGs was conducted using the databases of the AWMF, NICE, and the Guidelines International Network (GIN). AWMF-equivalent evidence quality levels S2e and S3 CPGs were included. Recommendations on monitoring were extracted and evaluated, focusing on their level of detail regarding monitoring frequency, parameters, and consequences and their level of evidence, respectively. Results A total of 29 CPGs were reviewed, and 163 recommendations on monitoring were extracted and evaluated. Recommendations provided a low level of detail regarding monitoring frequency in 34.4% of cases ( n = 56), regarding parameters in 25.2% of cases ( n = 41), and regarding consequences in 84.7% of cases ( n = 138). A level of evidence was reported for 87 of 163 recommendations only, and if available, it was often low. Only a small proportion (6.7%; n = 11) of recommendations were formulated negatively as ‘do-not’ recommendations. Conclusions The frequent lack of evidence or low level of evidence for monitoring recommendations, as well as the lack of detail in these recommendations, may lead to medical underuse, yet also to overuse, causing uncertainty among physicians and unnecessary diagnostic cascades. This has significant implications for patient harm, as well as financial and personnel burdens on the healthcare system. One potential solution could be the implementation of more ‘do-not’ recommendations in CPGs. However, overcoming systemic barriers is essential to enable the generation of high-quality evidence on monitoring.Open Access funding enabled and organized by Projekt DEAL.Gemeinsame Bundesausschusshttps://doi.org/10.13039/501100014840Universitätsklinikum Erlangen (8546
Generation and testing of GP33-41 and GP33-C41M epitope carrying antigen targeting antibodies for understanding CD8+ T cell responses directed against the lymphocytic choriomeningitis virus (LCMV)
No full textTrotz jahrelanger intensiver Forschung steht die moderne Medizin bei der Prävention und vollständigen Befreiung des Organismus von persistierenden Virusinfektionen wie dem Humanen Immundefizienz-Virus (HIV) und dem Epstein-Barr-Virus (EBV) weiterhin vor großen Herausforderungen. Eine mögliche Strategie, um Schutz und eine vollständige virale Elimination zu erreichen, ist die Induktion von pathogenspezifischen T-Zell-Antworten. Ein wichtiger Akteur in diesem Zusammenhang sind dendritische Zellen (DCs): Effektive und spezialisierte Antigen-präsentierende Zellen, die als Schnittstelle zwischen angeborenen und adaptiven Immunantworten fungieren. In früheren Arbeiten hat die Gruppe von Diana Dudziak rekombinante Antikörper, welche das Modellantigen Ovalbmin tragen und gegen einen Endozytose-fähigen Rezeptor auf der Zelloberfläche von DCs gerichtet waren genutzt, um T-Zell-Antworten gegen das an den Antikörper gekoppelte Antigen zu induzieren. In diesem Zusammenhang des Antigen-Targeting wurden die C-Typ-Lektin-Rezeptoren, DEC205 und DCIR2, sowie die Fc-Rezeptoren FcγRIIB, FcγRIII und FcγRIV untersucht. Dabei wurden vielversprechende Ergebisse erzielt. Wir stellen hier die Hypothese auf, dass Antigen-Targeting auch eine Möglichkeit für die Verabreichung im Sinne einer Immunisierung gegen natürliche Antigene und/oder ihrer Peptide ist. Um den Ansatz des Antikörper-vermittelten Bereitstellung von Antigenen für DCs auf einen viralen Kontext auszuweiten, wurde in der hier vorgestellten Studie das virale Epitop GP33-41 des Lymphozytären Choriomeningitis Virus (LCMV) verwendet. Das LCMV-Virus ist ein bekanntes virales Modellsystem für chronische und akute virale Infektionen. Es liegt in verschiedenen Varianten vor, bei denen einzelne Mutationen im Glykoprotein unterschiedliche Infektionserscheinungen bewirken. Diese Varianten werden als GP33-41 und GP33-C41M bezeichnet. Die Immunisierung mit diesen Peptidvarianten wird es daher in Zukunft ermöglichen, die T-Zell-Antworten in Abhängigkeit von denjenigen DC-Subpopulation zu untersuchen, an welche die Antigen-tragenden Antikörper zuvor gebunden haben.
Aus zuvor klonierten Plasmiden der Antikörpervarianten wurden im ersten Ziel der hier vorgestellten Arbeit Antikörper hergestellt, die entweder gegen DEC205 oder DCIR2, als Vertreter der C-Typ-Lektin-Rezeptorfamilie, oder gegen FcγRIIB und FcγRIII, FcγRIIB allein oder gegen FcγIV als Vertreter der Fc-Rezeptorfamilie gerichtet sind. Darüber hinaus wurden nicht bindende Isotyp-Varianten erzeugt. Jeder Antikörper trug entweder GP33-41 oder GP33-C41M als immunodominantes LCMV-CD8+-T-Zell-Epitop. Insgesamt wurden zwölf Antikörper hergestellt. Im zweiten Ziel dieser Arbeit wurden die Eigenschaften dieser neu hergestellten Antikörper auf Bindung und Internalisierung in die Zielzellpopulationen getestet. Hier waren insbesondere konventionelle Dendritische Zellen Typ 1 (cDC1) und 2 (cDC2) von Interesse
Machine learning for myocarditis diagnosis using cardiovascular magnetic resonance: a systematic review, diagnostic test accuracy meta-analysis, and comparison with human physicians
No full textMyocarditis is an inflammation of heart tissue. Cardiovascular magnetic resonance imaging (CMR) has emerged as an important non-invasive imaging tool for diagnosing myocarditis, however, interpretation remains a challenge for novice physicians. Advancements in machine learning (ML) models have further improved diagnostic accuracy, demonstrating good performance. Our study aims to assess the diagnostic accuracy of ML in identifying myocarditis using CMR. A systematic search was performed using PubMed, Embase, Web of Science, Cochrane, and Scopus to identify studies reporting the diagnostic accuracy of ML in the detection of myocarditis using CMR. The included studies evaluated both image-based and report-based assessments using various ML models. Diagnostic accuracy was estimated using a Random-Effects model (R software). We found a total of 141 ML model results from a total of 12 studies, which were included in the systematic review. The best models achieved 0.93 (95% Confidence Interval (CI) 0.88–0.96) sensitivity and 0.95 (95% CI 0.89–0.97) specificity. Pooled area under the curve was 0.97 (95% CI 0.93–0.98). Comparisons with human physicians showed comparable results for diagnostic accuracy of myocarditis. Quality assessment concerns and heterogeneity were present. CMR augmented using ML models with advanced algorithms can provide high diagnostic accuracy for myocarditis, even surpassing novice CMR radiologists. However, high heterogeneity, quality assessment concerns, and lack of information on cost-effectiveness may limit the clinical implementation of ML. Future investigations should explore cost-effectiveness and minimize biases in their methodologies
Elektrochemische Wasserstoffspeicherung durch elektrokatalytische Dehydrierung von Isopropanol
No full textGreen hydrogen from water electrolysis based on renewable energies will be crucial in decarbonizing society. The conversion of electrical energy into chemical energy opens up an enormous potential for storing renewable energy surpluses that can later be used when needed. Nonetheless, storing large amounts of hydrogen remains challenging because of its low energy storage capacity per unit volume at room temperature (3 Wh L-1). Over the past decade, hydrogen storage in liquid organic hydrogen carriers (LOHC) has attracted considerable attention. While classical LOHC systems store hydrogen thermocatalytically and release it on demand, this work investigated a low-temperature electrochemical LOHC (EC-LOHC) using acetone (ACE) and isopropanol (IPA, 2-propanol) as a hydrogen carrier system. The EC-LOHC comprises the electrochemical hydrogenation unit (EHU) and the electrochemical dehydrogenation unit (EDU), whereby the following work focused on the IPA EDU, representing the release of H2:
• By investigating the influence of temperature, fuel concentration, reactant, product mixtures, and the flow rate on the EDU polarization curves, a maximum dehydrogenation current density of 375 mA cm-2 was achieved.
• Based on the experimental results and thermodynamics, an efficiency calculation for a power-to-power chain (PtP) comprising coupled water electrolysis and hydrogen fuel cell systems compares the investigated EC-LOHC to current hydrogen storage technologies. The PtP analysis reveals that the ACE/IPA EC-LOHC can compete with existing hydrogen storage technologies, offering potential as a stationary seasonal storage of renewable energies.
• The EDU functions as a membrane electrode assembly (MEA) isopropanol oxidation reaction (IOR) model at low OCV losses. The comparison of the EDU to the direct isopropanol fuel cell (DIFC) shows how ACE/IPA crossover impacts the DIFC cathode. This finding reveals the prospects of new membranes that attenuate fuel crossover or new oxygen reduction reaction (ORR) catalysts that are inactive for the IOR.
• Rotating disk electrode ORR experiments scrutinize the distinct impact of ACE/IPA on the ORR, imitating the crossover in the DIFC. ACE crossover barely affects the ORR, whereas an IPA crossover is oxidized, impeding the ORR yielding cathodic DIFC losses.
• The potential acetone/isopropanol-induced MEA degradation was evaluated using hydrogen fuel cells as an analytical tool before and after EDU and DIFC operation