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- Johns Hopkins School of Medicine (18)
- IZKF Nachwuchsgruppe Geweberegeneration für muskuloskelettale Erkrankungen (7)
- Clinical Trial Center (CTC) / Zentrale für Klinische Studien Würzburg (ZKSW) (5)
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- Department of Biomedical Imaging, National Cerebral and Cardiovascular Research Center, Suita, Japan (2)
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- D-1221-2009 (1)
Die Riesenzellarteriitis (RZA) ist in der Altersgruppe der über 50-Jährigen die häufigste idiopathische systemische Vaskulitis. Die Erkrankung bedarf einer zeitnahen Diagnostik und Therapie, um schwere Komplikationen wie eine Erblindung oder einen Schlaganfall zu vermeiden. Die Rezidivneigung erfordert eine mehrjährige, zum Teil lebenslange Glukokortikoid(GC)-Therapie, was das Risiko GC-induzierter Langzeitnebenwirkungen erhöht. Daher wird bei der Mehrzahl der Patienten eine additive GC-einsparende Therapie empfohlen. Hierzu steht der Anti-IL-6-Rezeptor-Antikörper Tocilizumab in subkutaner Applikation als zugelassene Substanz zur Verfügung, alternativ kann Methotrexat (MTX) eingesetzt werden (off-label).
Hintergrund und Ziel
Telemedizinische Schlaganfall-Netzwerke tragen dazu bei, die Schlaganfallversorgung und insbesondere den Zugang zu zeitkritischen Schlaganfalltherapien in vorrangig strukturschwachen, ländlichen Regionen zu gewährleisten. Ziel ist eine Darstellung der Nutzungsfrequenz und regionalen Verteilung dieser Versorgungsstruktur.
Methoden
Die Kommission „Telemedizinische Schlaganfallversorgung“ der Deutschen Schlaganfall-Gesellschaft führte eine Umfragestudie in allen Schlaganfall-Netzwerken durch.
Ergebnisse
In Deutschland sind 22 telemedizinische Schlaganfall-Netzwerke aktiv, welche insgesamt 43 Zentren (pro Netzwerk: Median 1,5, Interquartilsabstand [IQA] 1–3) sowie 225 Kooperationskliniken (pro Netzwerk: Median 9, IQA 4–17) umfassen und an einem unmittelbaren Zugang zur Schlaganfallversorgung für 48 Mio. Menschen teilhaben. Im Jahr 2018 wurden 38.211 Telekonsile (pro Netzwerk: Median 1340, IQA 319–2758) durchgeführt. Die Thrombolyserate betrug 14,1 % (95 %-Konfidenzintervall 13,6–14,7 %), eine Verlegung zur Thrombektomie wurde bei 7,9 % (95 %-Konfidenzintervall 7,5–8,4 %) der ischämischen Schlaganfallpatienten initiiert. Das Finanzierungssystem ist uneinheitlich mit einem Vergütungssystem für die Zentrumsleistungen in nur drei Bundesländern.
Diskussion
Etwa jeder 10. Schlaganfallpatient wird telemedizinisch behandelt. Die telemedizinischen Schlaganfall-Netzwerke erreichen vergleichbar hohe Lyseraten und Verlegungen zur Thrombektomie wie neurologische Stroke-Units und tragen zur Sicherstellung einer flächendeckenden Schlaganfallversorgung bei. Eine netzwerkübergreifende Sicherstellung der Finanzierung und einheitliche Erhebung von Qualitätssicherungsdaten haben das Potenzial diese Versorgungsstruktur zukünftig weiter zu stärken.
T cell exhaustion is a hallmark of cancer and persistent infections, marked by inhibitory receptor upregulation, diminished cytokine secretion, and impaired cytolytic activity. Terminally exhausted T cells are steadily replenished by a precursor population (Tpex), but the metabolic principles governing Tpex maintenance and the regulatory circuits that control their exhaustion remain incompletely understood. Using a combination of gene-deficient mice, single-cell transcriptomics, and metabolomic analyses, we show that mitochondrial insufficiency is a cell-intrinsic trigger that initiates the functional exhaustion of T cells. At the molecular level, we find that mitochondrial dysfunction causes redox stress, which inhibits the proteasomal degradation of hypoxia-inducible factor 1α (HIF-1α) and promotes the transcriptional and metabolic reprogramming of Tpex cells into terminally exhausted T cells. Our findings also bear clinical significance, as metabolic engineering of chimeric antigen receptor (CAR) T cells is a promising strategy to enhance the stemness and functionality of Tpex cells for cancer immunotherapy.
Axon degeneration and functional decline in myelin diseases are often attributed to loss of myelin but their relation is not fully understood. Perturbed myelinating glia can instigate chronic neuroinflammation and contribute to demyelination and axonal damage. Here we study mice with distinct defects in the proteolipid protein 1 gene that develop axonal damage which is driven by cytotoxic T cells targeting myelinating oligodendrocytes. We show that persistent ensheathment with perturbed myelin poses a risk for axon degeneration, neuron loss, and behavioral decline. We demonstrate that CD8\(^+\) T cell-driven axonal damage is less likely to progress towards degeneration when axons are efficiently demyelinated by activated microglia. Mechanistically, we show that cytotoxic T cell effector molecules induce cytoskeletal alterations within myelinating glia and aberrant actomyosin constriction of axons at paranodal domains. Our study identifies detrimental axon-glia-immune interactions which promote neurodegeneration and possible therapeutic targets for disorders associated with myelin defects and neuroinflammation.
Butyrophilin (BTN)–3A and BTN2A1 molecules control the activation of human Vγ9Vδ2 T cells during T cell receptor (TCR)-mediated sensing of phosphoantigens (PAg) derived from microbes and tumors. However, the molecular rules governing PAg sensing remain largely unknown. Here, we establish three mechanistic principles of PAg-mediated γδ T cell activation. First, in humans, following PAg binding to the intracellular BTN3A1-B30.2 domain, Vγ9Vδ2 TCR triggering involves the extracellular V-domain of BTN3A2/BTN3A3. Moreover, the localization of both protein domains on different chains of the BTN3A homo-or heteromers is essential for efficient PAg-mediated activation. Second, the formation of BTN3A homo-or heteromers, which differ in intracellular trafficking and conformation, is controlled by molecular interactions between the juxtamembrane regions of the BTN3A chains. Finally, the ability of PAg not simply to bind BTN3A-B30.2, but to promote its subsequent interaction with the BTN2A1-B30.2 domain, is essential for T-cell activation. Defining these determinants of cooperation and the division of labor in BTN proteins improves our understanding of PAg sensing and elucidates a mode of action that may apply to other BTN family members.
Herpes simplex virus 1 (HSV-1) infection and stress responses disrupt transcription termination by RNA Polymerase II (Pol II). In HSV-1 infection, but not upon salt or heat stress, this is accompanied by a dramatic increase in chromatin accessibility downstream of genes. Here, we show that the HSV-1 immediate-early protein ICP22 is both necessary and sufficient to induce downstream open chromatin regions (dOCRs) when transcription termination is disrupted by the viral ICP27 protein. This is accompanied by a marked ICP22-dependent loss of histones downstream of affected genes consistent with impaired histone repositioning in the wake of Pol II. Efficient knock-down of the ICP22-interacting histone chaperone FACT is not sufficient to induce dOCRs in ΔICP22 infection but increases dOCR induction in wild-type HSV-1 infection. Interestingly, this is accompanied by a marked increase in chromatin accessibility within gene bodies. We propose a model in which allosteric changes in Pol II composition downstream of genes and ICP22-mediated interference with FACT activity explain the differential impairment of histone repositioning downstream of genes in the wake of Pol II in HSV-1 infection.
Immune checkpoint blockade therapy is beneficial and even curative for some cancer patients. However, the majority don’t respond to immune therapy. Across different tumor types, pre-existing T cell infiltrates predict response to checkpoint-based immunotherapy. Based on in vitro pharmacological studies, mouse models and analyses of human melanoma patients, we show that the cytokine GDF-15 impairs LFA-1/β2-integrin-mediated adhesion of T cells to activated endothelial cells, which is a pre-requisite of T cell extravasation. In melanoma patients, GDF-15 serum levels strongly correlate with failure of PD-1-based immune checkpoint blockade therapy. Neutralization of GDF-15 improves both T cell trafficking and therapy efficiency in murine tumor models. Thus GDF-15, beside its known role in cancer-related anorexia and cachexia, emerges as a regulator of T cell extravasation into the tumor microenvironment, which provides an even stronger rationale for therapeutic anti-GDF-15 antibody development.
The neuronal RNA-binding protein Ptbp2 regulates neuronal differentiation by modulating alternative splicing programs in the nucleus. Such programs contribute to axonogenesis by adjusting the levels of protein isoforms involved in axon growth and branching. While its functions in alternative splicing have been described in detail, cytosolic roles of Ptbp2 for axon growth have remained elusive. Here, we show that Ptbp2 is located in the cytosol including axons and growth cones of motoneurons, and that depletion of cytosolic Ptbp2 affects axon growth. We identify Ptbp2 as a major interactor of the 3’ UTR of Hnrnpr mRNA encoding the RNA-binding protein hnRNP R. Axonal localization of Hnrnpr mRNA and local synthesis of hnRNP R protein are strongly reduced when Ptbp2 is depleted, leading to defective axon growth. Ptbp2 regulates hnRNP R translation by mediating the association of Hnrnpr with ribosomes in a manner dependent on the translation factor eIF5A2. Our data thus suggest a mechanism whereby cytosolic Ptbp2 modulates axon growth by fine-tuning the mRNA transport and local synthesis of an RNA-binding protein.
Elevated and low blood pressure (BP) may lead to poor functional outcome after ischemic stroke, which is conflicting. Hence, there must be another factor—such as cerebral small vessel disease (cSVD) -interacting with BP and thus, affecting outcome. Here, we investigate the relationship between BP and cSVD regarding outcome after stroke. Data of 423/503 stroke patients were prospectively analyzed. Diastolic (DBP) and systolic BP (SBP) were collected on hospital admission (BP\(_{ad}\)) and over the first 72 h (BP\(_{72h}\)). cSVD-burden was determined on MR-scans. Good functional outcome was defined as a modified Rankin Scale score ≤ 2 at hospital discharge and 12 months thereafter. cSVD was a predictor of poor outcome (OR 2.8; p < 0.001). SBPad, DBP\(_{ad}\) and SBP\(_{72h}\) were not significantly associated with outcome at any time. A significant relationship was found between DBP\(_{72h}\), (p < 0.01), cSVD (p = 0.013) and outcome at discharge. At 12 months, we found a relationship between outcome and DBP\(_{72h}\) (p = 0.018) and a statistical tendency regarding cSVD (p = 0.08). Changes in DBP72h were significantly related with outcome. There was a U-shaped relationship between DBP\(_{72h}\) and outcome at discharge. Our results suggest an individualized stroke care by either lowering or elevating DBP depending on cSVD-burden in order to influence functional outcome.
Air pollution is associated with morbidity and mortality worldwide. We investigated the impact of improved air quality during the economic lockdown during the SARS-Cov2 pandemic on emergency room (ER) admissions in Germany. Weekly aggregated clinical data from 33 hospitals were collected in 2019 and 2020. Hourly concentrations of nitrogen and sulfur dioxide (NO2, SO2), carbon and nitrogen monoxide (CO, NO), ozone (O3) and particulate matter (PM10, PM2.5) measured by ground stations and meteorological data (ERA5) were selected from a 30 km radius around the corresponding ED. Mobility was assessed using aggregated cell phone data. A linear stepwise multiple regression model was used to predict ER admissions. The average weekly emergency numbers vary from 200 to over 1600 cases (total n = 2,216,217). The mean maximum decrease in caseload was 5 standard deviations. With the enforcement of the shutdown in March, the mobility index dropped by almost 40%. Of all air pollutants, NO2 has the strongest correlation with ER visits when averaged across all departments. Using a linear stepwise multiple regression model, 63% of the variation in ER visits is explained by the mobility index, but still 6% of the variation is explained by air quality and climate change.
Automated analysis of the inner ear anatomy in radiological data instead of time-consuming manual assessment is a worthwhile goal that could facilitate preoperative planning and clinical research. We propose a framework encompassing joint semantic segmentation of the inner ear and anatomical landmark detection of helicotrema, oval and round window. A fully automated pipeline with a single, dual-headed volumetric 3D U-Net was implemented, trained and evaluated using manually labeled in-house datasets from cadaveric specimen (N = 43) and clinical practice (N = 9). The model robustness was further evaluated on three independent open-source datasets (N = 23 + 7 + 17 scans) consisting of cadaveric specimen scans. For the in-house datasets, Dice scores of 0.97 and 0.94, intersection-over-union scores of 0.94 and 0.89 and average Hausdorf distances of 0.065 and 0.14 voxel units were achieved. The landmark localization task was performed automatically with an average localization error of 3.3 and 5.2 voxel units. A robust, albeit reduced performance could be
attained for the catalogue of three open-source datasets. Results of the ablation studies with 43 mono-parametric variations of the basal architecture and training protocol provided task-optimal parameters for both categories. Ablation studies against single-task variants of the basal architecture showed a clear performance beneft of coupling landmark localization with segmentation and a dataset-dependent performance impact on segmentation ability.
This study evaluated the influence of different vascular reconstruction kernels on the image quality of CT angiographies of the lower extremity runoff using a 1st-generation photon-counting-detector CT (PCD-CT) compared with dose-matched examinations on a 3rd-generation energy-integrating-detector CT (EID-CT). Inducing continuous extracorporeal perfusion in a human cadaveric model, we performed CT angiographies of eight upper leg arterial runoffs with radiation dose-equivalent 120 kVp acquisition protocols (CTDIvol 5 mGy). Reconstructions were executed with different vascular kernels, matching the individual modulation transfer functions between scanners. Signal-to-noise-ratios (SNR) and contrast-to-noise-ratios (CNR) were computed to assess objective image quality. Six radiologists evaluated image quality subjectively using a forced-choice pairwise comparison tool. Interrater agreement was determined by calculating Kendall’s concordance coefficient (W). The intraluminal attenuation of PCD-CT images was significantly higher than of EID-CT (414.7 ± 27.3 HU vs. 329.3 ± 24.5 HU; p < 0.001). Using comparable kernels, image noise with PCD-CT was significantly lower than with EID-CT (p ≤ 0.044). Correspondingly, SNR and CNR were approximately twofold higher for PCD-CT (p < 0.001). Increasing the spatial frequency for PCD-CT reconstructions by one level resulted in similar metrics compared to EID-CT (CNRfat; EID-CT Bv49: 21.7 ± 3.7 versus PCD-CT Bv60: 21.4 ± 3.5). Overall image quality of PCD-CTA achieved ratings superior to EID-CTA irrespective of the used reconstruction kernels (best: PCD-CT Bv60; worst: EID-CT Bv40; p < 0.001). Interrater agreement was good (W = 0.78). Concluding, PCD-CT offers superior intraluminal attenuation, SNR, and CNR compared to EID-CT in angiographies of the upper leg arterial runoff. Combined with improved subjective image quality, PCD-CT facilitates the use of sharper convolution kernels and ultimately bears the potential of improved vascular structure assessability.
Psychosocial factors affect mental health and health-related quality of life (HRQL) in a complex manner, yet gender differences in these interactions remain poorly understood. We investigated whether psychosocial factors such as social support and personal and work-related concerns impact mental health and HRQL differentially in women and men during the first year of the COVID-19 pandemic. Between June and October 2020, the first part of a COVID-19-specific program was conducted within the “Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB)” cohort study, a representative age- and gender-stratified sample of the general population of Würzburg, Germany. Using psychometric networks, we first established the complex relations between personal social support, personal and work-related concerns, and their interactions with anxiety, depression, and HRQL. Second, we tested for gender differences by comparing expected influence, edge weight differences, and stability of the networks. The network comparison revealed a significant difference in the overall network structure. The male (N = 1370) but not the female network (N = 1520) showed a positive link between work-related concern and anxiety. In both networks, anxiety was the most central variable. These findings provide further evidence that the complex interplay of psychosocial factors with mental health and HRQL decisively depends on gender. Our results are relevant for the development of gender-specific interventions to increase resilience in times of pandemic crisis.
Minimally invasive endovascular interventions have become an important tool for the treatment of cardiovascular diseases such as ischemic heart disease, peripheral artery disease, and stroke. X-ray fluoroscopy and digital subtraction angiography are used to precisely guide these procedures, but they are associated with radiation exposure for patients and clinical staff. Magnetic Particle Imaging (MPI) is an emerging imaging technology using time-varying magnetic fields combined with magnetic nanoparticle tracers for fast and highly sensitive imaging. In recent years, basic experiments have shown that MPI has great potential for cardiovascular applications. However, commercially available MPI scanners were too large and expensive and had a small field of view (FOV) designed for rodents, which limited further translational research. The first human-sized MPI scanner designed specifically for brain imaging showed promising results but had limitations in gradient strength, acquisition time and portability. Here, we present a portable interventional MPI (iMPI) system dedicated for real-time endovascular interventions free of ionizing radiation. It uses a novel field generator approach with a very large FOV and an application-oriented open design enabling hybrid approaches with conventional X-ray-based angiography. The feasibility of a real-time iMPI-guided percutaneous transluminal angioplasty (PTA) is shown in a realistic dynamic human-sized leg model.
Social buffering, a phenomenon where social presence can reduce anxiety and fear-related autonomic responses, has been studied in numerous laboratory settings. The results suggest that the familiarity of the interaction partner influences social buffering while also providing some evidence for gender effects. In the laboratory, however, it is difficult to mimic the complexity of real-life social interactions. Consequently, the social modulation of anxiety and related autonomic responses in everyday life remains poorly understood. We used smartphone-based Ecological Momentary Assessment (EMA) combined with wearable electrocardiogram sensors to investigate how everyday-life social interactions affect state anxiety and related cardiac changes in women and men. On five consecutive days, 96 healthy young participants (53% women) answered up to six EMA surveys per day, indicating characteristics of their most recent social interaction and the respective interaction partner(s). In women, our results showed lower heart rate in the presence of a male interaction partner. Men showed the same effect with female interaction partners. Moreover, only women showed decreased heart rate and increased heart rate variability with increasing interaction partner familiarity. These findings specify the conditions under which social interactions reduce anxiety-related responses in women and men.
Photon-counting detector (PCD) CT allows for ultra-high-resolution (UHR) examinations of the shoulder without requiring an additional post-patient comb filter to narrow the detector aperture. This study was designed to compare the PCD performance with a high-end energy-integrating detector (EID) CT. Sixteen cadaveric shoulders were examined with both scanners using dose-matched 120 kVp acquisition protocols (low-dose/full-dose: CTDI\(_{vol}\) = 5.0/10.0 mGy). Specimens were scanned in UHR mode with the PCD-CT, whereas EID-CT examinations were conducted in accordance with the clinical standard as “non-UHR”. Reconstruction of EID data employed the sharpest kernel available for standard-resolution scans (ρ\(_{50}\) = 12.3 lp/cm), while PCD data were reconstructed with both a comparable kernel (11.8 lp/cm) and a sharper dedicated bone kernel (16.5 lp/cm). Six radiologists with 2–9 years of experience in musculoskeletal imaging rated image quality subjectively. Interrater agreement was analyzed by calculation of the intraclass correlation coefficient in a two-way random effects model. Quantitative analyses comprised noise recording and calculating signal-to-noise ratios based on attenuation measurements in bone and soft tissue. Subjective image quality was higher in UHR-PCD-CT than in EID-CT and non-UHR-PCD-CT datasets (all p < 0.001). While low-dose UHR-PCD-CT was considered superior to full-dose non-UHR studies on either scanner (all p < 0.001), ratings of low-dose non-UHR-PCD-CT and full-dose EID-CT examinations did not differ (p > 0.99). Interrater reliability was moderate, indicated by a single measures intraclass correlation coefficient of 0.66 (95% confidence interval: 0.58–0.73; p < 0.001). Image noise was lowest and signal-to-noise ratios were highest in non-UHR-PCD-CT reconstructions at either dose level (p < 0.001). This investigation demonstrates that superior depiction of trabecular microstructure and considerable denoising can be realized without additional radiation dose by employing a PCD for shoulder CT imaging. Allowing for UHR scans without dose penalty, PCD-CT appears as a promising alternative to EID-CT for shoulder trauma assessment in clinical routine.
Long-term sequelae in hospitalized Coronavirus Disease 2019 (COVID-19) patients may result in limited quality of life. The current study aimed to determine health-related quality of life (HRQoL) after COVID-19 hospitalization in non-intensive care unit (ICU) and ICU patients. This is a single-center study at the University Hospital of Wuerzburg, Germany. Patients eligible were hospitalized with COVID-19 between March 2020 and December 2020. Patients were interviewed 3 and 12 months after hospital discharge. Questionnaires included the European Quality of Life 5 Dimensions 5 Level (EQ-5D-5L), patient health questionnaire-9 (PHQ-9), the generalized anxiety disorder 7 scale (GAD-7), FACIT fatigue scale, perceived stress scale (PSS-10) and posttraumatic symptom scale 10 (PTSS-10). 85 patients were included in the study. The EQ5D-5L-Index significantly differed between non-ICU (0.78 ± 0.33 and 0.84 ± 0.23) and ICU (0.71 ± 0.27; 0.74 ± 0.2) patients after 3- and 12-months. Of non-ICU 87% and 80% of ICU survivors lived at home without support after 12 months. One-third of ICU and half of the non-ICU patients returned to work. A higher percentage of ICU patients was limited in their activities of daily living compared to non-ICU patients. Depression and fatigue were present in one fifth of the ICU patients. Stress levels remained high with only 24% of non-ICU and 3% of ICU patients (p = 0.0186) having low perceived stress. Posttraumatic symptoms were present in 5% of non-ICU and 10% of ICU patients. HRQoL is limited in COVID-19 ICU patients 3- and 12-months post COVID-19 hospitalization, with significantly less improvement at 12-months compared to non-ICU patients. Mental disorders were common highlighting the complexity of post-COVID-19 symptoms as well as the necessity to educate patients and primary care providers about monitoring mental well-being post COVID-19.
Topological differences and confounders of mental rotation in cervical dystonia and blepharospasm
(2023)
Mental rotation (mR) bases on imagination of actual movements. It remains unclear whether there is a specific pattern of mR impairment in focal dystonia. We aimed to investigate mR in patients with cervical dystonia (CD) and blepharospasm (BS) and to assess potential confounders. 23 CD patients and 23 healthy controls (HC) as well as 21 BS and 19 hemifacial spasm (HS) patients were matched for sex, age, and education level. Handedness, finger dexterity, general reaction time, and cognitive status were assessed. Disease severity was evaluated by clinical scales. During mR, photographs of body parts (head, hand, or foot) and a non-corporal object (car) were displayed at different angles rotated within their plane. Subjects were asked to judge laterality of the presented image by keystroke. Both speed and correctness were evaluated. Compared to HC, CD and HS patients performed worse in mR of hands, whereas BS group showed comparable performance. There was a significant association of prolonged mR reaction time (RT) with reduced MoCA scores and with increased RT in an unspecific reaction speed task. After exclusion of cognitively impaired patients, increased RT in the mR of hands was confined to CD group, but not HS. While the question of whether specific patterns of mR impairment reliably define a dystonic endophenotype remains elusive, our findings point to mR as a useful tool, when used carefully with control measures and tasks, which may be capable of identifying specific deficits that distinguish between subtypes of dystonia.
Seed amplification assays (SAA) are becoming commonly used in synucleinopathies to detect α-synuclein aggregates. Studies in Parkinson’s disease (PD) and isolated REM-sleep behavior disorder (iRBD) have shown a considerably lower sensitivity in the olfactory epithelium than in CSF or skin. To get an insight into α-synuclein (α-syn) distribution within the nervous system and reasons for low sensitivity, we compared SAA assessment of nasal brushings and skin biopsies in PD (n = 27) and iRBD patients (n = 18) and unaffected controls (n = 30). α-syn misfolding was overall found less commonly in the olfactory epithelium than in the skin, which could be partially explained by the nasal brushing matrix exerting an inhibitory effect on aggregation. Importantly, the α-syn distribution was not uniform: there was a higher deposition of misfolded α-syn across all sampled tissues in the iRBD cohort compared to PD (supporting the notion of RBD as a marker of a more malignant subtype of synucleinopathy) and in a subgroup of PD patients, misfolded α-syn was detectable only in the olfactory epithelium, suggestive of the recently proposed brain-first PD subtype. Assaying α-syn of diverse origins, such as olfactory (part of the central nervous system) and skin (peripheral nervous system), could increase diagnostic accuracy and allow better stratification of patients.
Inflammation in the brain and gut is a critical component of several neurological diseases, such as Parkinson’s disease (PD). One trigger of the immune system in PD is aggregation of the pre-synaptic protein, α-synuclein (αSyn). Understanding the mechanism of propagation of αSyn aggregates is essential to developing disease-modifying therapeutics. Using a brain-first mouse model of PD, we demonstrate αSyn trafficking from the brain to the ileum of male mice. Immunohistochemistry revealed that the ileal αSyn aggregations are contained within CD11c+ cells. Using single-cell RNA sequencing, we demonstrate that ileal CD11c\(^+\) cells are microglia-like and the same subtype of cells is activated in the brain and ileum of PD mice. Moreover, by utilizing mice expressing the photo-convertible protein, Dendra2, we show that CD11c\(^+\) cells traffic from the brain to the ileum. Together these data provide a mechanism of αSyn trafficking between the brain and gut.
Pathogen-specific innate immune response patterns are distinctly affected by genetic diversity
(2023)
Innate immune responses vary by pathogen and host genetics. We analyze quantitative trait loci (eQTLs) and transcriptomes of monocytes from 215 individuals stimulated by fungal, Gram-negative or Gram-positive bacterial pathogens. We identify conserved monocyte responses to bacterial pathogens and a distinct antifungal response. These include 745 response eQTLs (reQTLs) and corresponding genes with pathogen-specific effects, which we find first in samples of male donors and subsequently confirm for selected reQTLs in females. reQTLs affect predominantly upregulated genes that regulate immune response via e.g., NOD-like, C-type lectin, Toll-like and complement receptor-signaling pathways. Hence, reQTLs provide a functional explanation for individual differences in innate response patterns. Our identified reQTLs are also associated with cancer, autoimmunity, inflammatory and infectious diseases as shown by external genome-wide association studies. Thus, reQTLs help to explain interindividual variation in immune response to infection and provide candidate genes for variants associated with a range of diseases.
Bioimages frequently exhibit low signal-to-noise ratios due to experimental conditions, specimen characteristics, and imaging trade-offs. Reliable segmentation of such ambiguous images is difficult and laborious. Here we introduce deepflash2, a deep learning-enabled segmentation tool for bioimage analysis. The tool addresses typical challenges that may arise during the training, evaluation, and application of deep learning models on ambiguous data. The tool’s training and evaluation pipeline uses multiple expert annotations and deep model ensembles to achieve accurate results. The application pipeline supports various use-cases for expert annotations and includes a quality assurance mechanism in the form of uncertainty measures. Benchmarked against other tools, deepflash2 offers both high predictive accuracy and efficient computational resource usage. The tool is built upon established deep learning libraries and enables sharing of trained model ensembles with the research community. deepflash2 aims to simplify the integration of deep learning into bioimage analysis projects while improving accuracy and reliability.
Ferroptosis is a form of cell death characterized by phospholipid peroxidation, where numerous studies have suggested that the induction of ferroptosis is a therapeutic strategy to target therapy refractory cancer entities. Ferroptosis suppressor protein 1 (FSP1), an NAD(P)H-ubiquinone reductase, is a key determinant of ferroptosis vulnerability, and its pharmacological inhibition was shown to strongly sensitize cancer cells to ferroptosis. A first generation of FSP1 inhibitors, exemplified by the small molecule iFSP1, has been reported; however, the molecular mechanisms underlying inhibition have not been characterized in detail. In this study, we explore the species-specific inhibition of iFSP1 on the human isoform to gain insights into its mechanism of action. Using a combination of cellular, biochemical, and computational methods, we establish a critical contribution of a species-specific aromatic architecture that is essential for target engagement. The results described here provide valuable insights for the rational development of second-generation FSP1 inhibitors combined with a tracer for screening the druggable pocket. In addition, we pose a cautionary notice for using iFSP1 in animal models, specifically murine models.
Present surgical situations require a bone adhesive which has not yet been developed for use in clinical applications. Recently, phosphoserine modified cements (PMC) based on mixtures of o-phosphoserine (OPLS) and calcium phosphates, such as tetracalcium phosphate (TTCP) or α-tricalcium phosphate (α-TCP) as well as chelate setting magnesium phosphate cements have gained increasing popularity for their use as mineral bone adhesives. Here, we investigated new mineral-organic bone cements based on phosphoserine and magnesium phosphates or oxides, which possess excellent adhesive properties. These were analyzed by X-ray diffraction, Fourier infrared spectroscopy and electron microscopy and subjected to mechanical tests to determine the bond strength to bone after ageing at physiological conditions. The novel biomineral adhesives demonstrate excellent bond strength to bone with approximately 6.6–7.3 MPa under shear load. The adhesives are also promising due to their cohesive failure pattern and ductile character. In this context, the new adhesive cements are superior to currently prevailing bone adhesives. Future efforts on bone adhesives made from phosphoserine and Mg2+ appear to be very worthwhile.
Das regulatorische Gerüst-Protein LASP1, welches aus der Krebsforschung bekannt ist, wurde 2012 in humanen Makrophagen, den Protagonisten der Atherosklerose nachgewiesen. LASP1 ist durch seine Lokalisation an dynamischen Aktinskelettkonstruktionen (vgl. Invadopodien, Podosomen), nachweislich an Zellmigration, Proliferation und Invasionsfähigkeit bestimmter Tumorzellen beteiligt. Aufgrund einer großen Schnittmenge der Entstehungsmechanismen und zugrundeliegenden Signalwegen von Krebserkrankungen und Atherosklerose wurde LASP1 im Zusammenhang der Atherosklerose untersucht. In einem 16 Wochen Hochfettdiätversuch zeigten LASP1.Ldlr-/--Mäuse mehr atherosklerotische Läsionen in der Gesamtaorta als Ldlr-/--Tiere, was eine athero-protektive Rolle von LASP1 nahelegt. Passend hierzu führte Stimulation mit oxLDL in Makrophagen zu einer Hochregulation von LASP1. Zusätzlich internalisierten LASP1-/--Makrophagen signifikant mehr oxLDL im Vergleich zu LASP1-exprimierenden Zellen. Analog zu den Daten aus der Krebsforschung konnte eine reduzierte endotheliale Adhäsion sowie chemotaktische Migration von Ldlr.LASP1-/--Monozyten im Vergleich zu Ldlr-/-- Monozyten festgestellt werden. Dies ließe isoliert betrachtet eine pro-atherogene Rolle von LASP1 vermuten. Ein Nachweis von LASP1 im Zellkern von BMDMs konnte, zusätzlich zum fehlenden Shuttelproteinpartner ZO-2, nicht erbracht werden. Die Interaktion von LASP1 mit Transkriptionsfaktoren scheint daher unwahrscheinlich. Kongruent mit diesen Ergebnissen zeigte sich keine Veränderung der Transkription, der Proteinexpression sowie Sekretion von TNF! und ADAM17 durch den LASP1-KO. Insgesamt kommt LASP1 eine zweifellos komplexe Rolle in der Atherogenese zu. Die Ergebnisse der HFD-Versuche legen nahe, dass die primär anti-atherosklerotischen Einflüsse von LASP1 in vivo gegenüber den eher pro-atherosklerotischen Effekten des Proteins in vitro überwiegen.
Ziel der vorliegenden Arbeit ist es, „Lanfranks ‚Chirurgia parva‘ in der Abschrift Konrad Schrecks von Aschaffenburg“1 anhand der von Ralf Vollmuth in seiner Habilitationsschrift „Traumatologie und Feldchirurgie an der Wende vom Mittelalter zur Neuzeit“ erarbeiteten Strukturvorgabe inhaltlich zu erschließen. Durch die Aufarbeitung verschiedener chirurgischer Fachbücher und Manuale unter Verwendung einer gemeinsamen Strukturvorlage soll ermöglicht werden, medizinhistorische Quellen kritisch-kontrastiv zu vergleichen. Das bedeutet, dass die Quellen zuerst ediert und anschließend gegebenenfalls übersetzt werden müssen. Im nächsten Schritt werden die verwendeten Arzneimittel – pflanzlicher, tierischer, mineralischer Herkunft – identifiziert und bestimmt. Im Anschluss werden Monographien mit den bestimmenden Inhaltsstoffen und Eigenschaften
erstellt. Anhand dieser Pflanzen- und Arzneistoffmonographien, die im Sinne einer Datenbank aufeinander aufbauen, sollte es dann möglich sein, unter modernen pharmakologischen Gesichtspunkten die Wirksamkeit der verwendeten Arzneimittel zu erschließen.
Eine ausreichende Zahl von Quellen, die nach einer gemeinsamen Strukturvorlage bearbeitet wurden, kann es schließlich ermöglichen, zu beurteilen, welche der beschriebenen Anwendungen repräsentativ waren, welche Außenseiterstellung einnahmen oder nur theoretische Ansätze bildeten, die praktisch keine Verwendung fanden.
Komplementärmedizinische Angebote in der Onkologie erleben eine hohe Nachfrage. Diese Studie sollte klären, ob bei Patienten ein Mehrbedarf an ganzheitlichen, tagesklinischen Angeboten besteht. Im Rahmen dieser Fragebogen-basierten Analyse sollten Zielgruppen identifiziert werden, die besonders hiervon profitieren könnten. Mithilfe eines Fragebogens wurden zwischen 08/2019 und 10/2020 294 ambulant behandelte onkologische Patienten des Comprehensive Cancer Centers Mainfranken an der Universitätsklinik Würzburg befragt. Der Fragebogen ist angelehnt an das etablierte Curriculum Mind-Body-Medizin der Kliniken Essen-Mitte und umfasst zehn Untergruppen. Statistisch signifikante Zusammenhänge wurden durch Anwendung des Chi-Quadrat Tests ermittelt. In allen untersuchten Lebensbereichen fanden sich Hinweise auf einen Mehrbedarf an komplementärmedizinischen Angeboten. Ein Drittel der Patienten gab an, aus eigener Kraft keine überdauernden Lebensstiländerungen herbeiführen zu können. Das höchste Gesundheitsbewusstsein zeigte sich in den Bereichen Ernährung, Bewegung und Entspannung. Trotzdem führte ein Großteil der Befragten empfohlene Maßnahmen nicht durch. Insbesondere die Bereiche Schlaf, Energielevel und psychische Belastung wiesen das größte Verbesserungspotential auf. Defizite in diesen Bereichen beeinflussten sich gegenseitig und konnten mit Unzufriedenheit und negativen Gedanken sowie geringer Veränderungsmotivation in Verbindung gebracht werden. Besonders betroffen waren erwerbstätige Patienten im Alter zwischen 40-65 Jahren. Frauen zeigten sich deutlich motivierter als Männer komplementärmedizinische Angebote zu nutzen. Gemäß unseren Ergebnissen und evidenzbasierten Empfehlungen der S3-Leitlinie Komplementärmedizin ergibt sich ein Mehrbedarf nach folgenden Angeboten: Supervidierte Sportprogramme, MBSR, Tai Chi/ Qigong, individuelle Ernährungsberatung und Selbsthilfegruppen für Angehörige. Durch Vermittlung von Gesundheitsbewusstsein sollten insbesondere Patientengruppen motiviert werden, die aus eigener Kraft ihre Situation nicht verbessern können. Um den Erfolg von gesundheitsfördernden Lebensstiländerungen überdauernd zu sichern, ist weitere Unterstützung nötig.
Adoptive cellular immunotherapy with chimeric antigen receptor (CAR) T cells is highly effective in haematological malignancies. This success, however, has not been achieved in solid tumours so far. In contrast to hematologic malignancies, solid tumours include a hostile tumour microenvironment (TME), that poses additional challenges for curative effects and consistent therapeutic outcome. These challenges manifest in physical and immunological barriers that dampen efficacy of the CAR T cells. Preclinical testing of novel cellular immunotherapies is performed mainly in 2D cell culture and animal experiments. While 2D cell culture is an easy technique for efficacy analysis, animal studies reveal information about toxicity in vivo. However, 2D cell culture cannot fully reflect the complexity observed in vivo, because cells are cultured without anchorage to a matrix and only short-term periods are feasible. Animal studies provide a more complex tissue environment, but xenografts often lack human stroma and tumour inoculation occurs mostly ectopically. This emphasises the need for standardisable and scalable tumour models with incorporated TME-aspects, which enable preclinical testing with enhanced predictive value for the clinical outcome of immunotherapies. Therefore, microphysiologic 3D tumour models based on the biological SISmuc (Small Intestinal mucosa and Submucosa) matrix with preserved basement membrane were engaged and improved in this work to serve as a modular and versatile tumour model for efficacy testing of CAR T cells. In order to reflect a variety of cancer entities, TME-aspects, long-term stability and to enhance the read-out options they were further adapted to achieve scalable and standardisable defined microphysiologic 3D tumour models. In this work, novel culture modalities (semi-static, sandwich-culture) were characterised and established that led to an increased and organised tissue generation and long-term stability. Application of the SISmuc matrix was extended to sarcoma and melanoma models and serial bioluminescence intensity (BLI)-based in vivo imaging analysis was established in the microphysiologic 3D tumour models, which represents a time-efficient read-out method for quality evaluation of the models and treatment efficacy analysis, that is independent of the cell phenotype. Isolation of cancer-associated-fibroblasts (CAFs) from lung (tumour) tissue was demonstrated and CAF-implementation further led to stromal-enriched microphysiologic 3D tumour models with in vivo-comparable tissue-like architecture. Presence of CAFs was confirmed by CAF-associated markers (FAP, α-SMA, MMP-2/-9) and cytokines correlated with CAF phenotype, angiogenesis, invasion and immunomodulation. Additionally, an endothelial cell barrier was implemented for static and dynamic culture in a novel bioreactor set-up, which is of particular interest for the analysis of immune cell diapedesis. Studies in microphysiologic 3D Ewing’s sarcoma models indicated that sarcoma cells could be sensitised for GD2-targeting CAR T cells. After enhancing the scale of assessment of the microphysiologic 3D tumour models and improving them for CAR T cell testing, the tumour models were used to analyse their sensitivity towards differently designed receptor tyrosine kinase-like orphan receptor 1 (ROR1) CAR T cells and to study the effects of the incorporated TME-aspects on the CAR T cell treatment respectively. ROR1 has been described as a suitable target for several malignancies including triple negative breast cancer (TNBC), as well as lung cancer. Therefore, microphysiologic 3D TNBC and lung cancer models were established. Analysis of ROR1 CAR T cells that differed in costimulation, spacer length and targeting domain, revealed, that the microphysiologic 3D tumour models are highly sensitive and can distinguish optimal from sub-optimal CAR design. Here, higher affinity of the targeting domain induced stronger anti-tumour efficacy and anti-tumour function depended on spacer length, respectively. Long-term treatment for 14 days with ROR1 CAR T cells was demonstrated in dynamic microphysiologic 3D lung tumour models, which did not result in complete tumour cell removal, whereas direct injection of CAR T cells into TNBC and lung tumour models represented an alternative route of application in addition to administration via the medium flow, as it induced strong anti-tumour response. Influence of the incorporated TME-aspects on ROR1 CAR T cell therapy represented by CAF-incorporation and/or TGF-β supplementation was analysed. Presence of TGF-β revealed that the specific TGF-β receptor inhibitor SD-208 improves ROR1 CAR T cell function, because it effectively abrogated immunosuppressive effects of TGF-β in TNBC models. Implementation of CAFs should provide a physical and immunological barrier towards ROR1 CAR T cells, which, however, was not confirmed, as ROR1 CAR T cell function was retained in the presence of CAFs in stromal-enriched microphysiologic 3D lung tumour models. The absence of an effect of CAF enrichment on CAR T cell efficacy suggests a missing component for the development of an immunosuppressive TME, even though immunomodulatory cytokines were detected in co-culture models. Finally, improved gene-edited ROR1 CAR T cells lacking exhaustion-associated genes (PD-1, TGF-β-receptor or both) were challenged by the combination of CAF-enrichment and TGF-β in microphysiologic 3D TNBC models. Results indicated that the absence of PD-1 and TGF-β receptor leads to improved CAR T cells, that induce strong tumour cell lysis, and are protected against the hostile TME. Collectively, the microphysiologic 3D tumour models presented in this work reflect aspects of the hostile TME of solid tumours, engage BLI-based analysis and provide long-term tissue homeostasis. Therefore, they present a defined, scalable, reproducible, standardisable and exportable model for translational research with enhanced predictive value for efficacy testing and candidate selection of cellular immunotherapy, as exemplified by ROR1 CAR T cells.
Purpose
To compare the performance of the dominant and nondominant hand during fundamental arthroscopic simulator training.
Methods
Surgical trainees who participated in a 2-day simulator training course between 2021 and 2023 were classified, according to their arthroscopic experience in beginners and competents. Only right-handed individuals with complete data sets were included in the study. Ambidexterity was trained using a box trainer (Fundamentals of Arthroscopic Surgery Training, Virtamed AG, Schlieren, Switzerland).Two tasks, periscoping for learning camera guidance and triangulation for additional instrument handling, were performed 4 times with the camera in the dominant hand and then in the nondominant hand. For each task, exercise time, camera path length, and instrument path length were recorded and analyzed.
Results
Out of 94 participants 74 right-handed individuals (22 females, 52 males) were classified to novices (n = 43, less than 10 independently performed arthroscopies) and competents (n = 31, more than 10 independently performed arthroscopies). Competents performed significantly better than novices. No significant difference was found after changing the guiding hand for the camera from the dominant to the nondominant hand regarding the camera path length and the instrument path length. Notably, tasks were performed even faster when using the camera in the nondominant hand.
Conclusions
Our data demonstrate that the learned manual skills during basic arthroscopic training are quickly transferred to the contralateral side. In consequence, additional fundamental skills training for camera guidance and instrument handling of the nondominant hand are not necessary.
Clinical Relevance
For skillful arthroscopy, camera guidance and instrument handing must be equally mastered with both hands. It is important to understand how hand dominance may affect learning during arthroscopic simulator training.
Introduction:
Fibromyalgia syndrome (FMS) and small fiber neuropathy (SFN) are distinct pain conditions that share commonalities and may be challenging as for differential diagnosis.
Objective:
To comprehensively investigate clinical characteristics of women with FMS and SFN to determine clinically applicable parameters for differentiation.
Methods:
We retrospectively analyzed medical records of 158 women with FMS and 53 with SFN focusing on pain-specific medical and family history, accompanying symptoms, additional diseases, and treatment. We investigated data obtained using standardized pain, depression, and anxiety questionnaires. We further analyzed test results and findings obtained in standardized small fiber tests.
Results:
FMS patients were on average ten years younger at symptom onset, described higher pain intensities requiring frequent change of pharmaceutics, and reported generalized pain compared to SFN. Pain in FMS was accompanied by irritable bowel or sleep disturbances, and in SFN by paresthesias, numbness, and impaired glucose metabolism (P < 0.01 each). Family history was informative for chronic pain and affective disorders in FMS (P < 0.001) and for neurological disorders in SFN patients (P < 0.001). Small fiber pathology in terms of skin denervation and/or thermal sensory threshold elevation was present in 110/158 (69.7 %) FMS patients and 39/53 (73.6 %) SFN patients. FMS patients mainly showed proximally reduced skin innervation and higher corneal nerve branch densities (p<0.001) whereas SFN patients were characterized by reduced cold detection and prolonged electrical A-delta conduction latencies (P < 0.05).
Conclusions:
Our data show that FMS and SFN differ substantially. Detailed pain, drug and family history, investigating blood glucose metabolism, and applying differential small fiber tests may help to improve diagnostic differentiation and targeted therapy.
Highlights
• The GLA variant S126G is not associated with Fabry symptoms in the presented case
• S126G has no effect on α-GAL A activity or Gb3 levels in this patient
• S126G sensory neurons show no electrophysiological abnormalities
Abstract
Fabry disease (FD) is a life-limiting disorder characterized by intracellular globotriaosylceramide (Gb3) accumulations. The underlying α-galactosidase A (α-GAL A) deficiency is caused by variants in the gene GLA. Variants of unknown significance (VUS) are frequently found in GLA and challenge clinical management. Here, we investigated a 49-year old man with cryptogenic lacunar cerebral stroke and the chance finding of the VUS S126G, who was sent to our center for diagnosis and initiation of a costly and life-long FD-specific treatment. We combined clinical examination with in vitro investigations of dermal fibroblasts (HDF), induced pluripotent stem cells (iPSC), and iPSC-derived sensory neurons. We analyzed α-GAL A activity in iPSC, Gb3 accumulation in all three cell types, and action potential firing in sensory neurons. Neurological examination and small nerve fiber assessment was normal except for reduced distal skin innervation. S126G iPSC showed normal α-GAL A activity compared to controls and no Gb3 deposits were found in all three cell types. Baseline electrophysiological characteristics of S126G neurons showed no difference compared to healthy controls as investigated by patch-clamp recordings. We pioneer multi-level cellular characterization of the VUS S126G using three cell types derived from a patient and provide further evidence for the benign nature of S126G in GLA, which is of great importance in the management of such cases in clinical practice.
Highlights
• Beta-Guided programming is an innovative approach that may streamline the programming process for PD patients with STN DBS.
• While preliminary findings from our study suggest that Beta Titration may potentially mitigate STN overstimulation and enhance symptom control,
• Our results demonstrate that beta-guided programming significantly reduces programming time, suggesting it could be efficiently integrated into routine clinical practice using a commercially available patient programmer.
Background
Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for advanced Parkinson's disease (PD). Clinical outcomes after DBS can be limited by poor programming, which remains a clinically driven, lengthy and iterative process. Electrophysiological recordings in PD patients undergoing STN-DBS have shown an association between STN spectral power in the beta frequency band (beta power) and the severity of clinical symptoms. New commercially-available DBS devices now enable the recording of STN beta oscillations in chronically-implanted PD patients, thereby allowing investigation into the use of beta power as a biomarker for DBS programming.
Objective
To determine the potential advantages of beta-guided DBS programming over clinically and image-guided programming in terms of clinical efficacy and programming time.
Methods
We conducted a randomized, blinded, three-arm, crossover clinical trial in eight Parkinson's patients with STN-DBS who were evaluated three months after DBS surgery. We compared clinical efficacy and time required for each DBS programming paradigm, as well as DBS parameters and total energy delivered between the three strategies (beta-, clinically- and image-guided).
Results
All three programming methods showed similar clinical efficacy, but the time needed for programming was significantly shorter for beta- and image-guided programming compared to clinically-guided programming (p < 0.001).
Conclusion
Beta-guided programming may be a useful and more efficient approach to DBS programming in Parkinson's patients with STN-DBS. It takes significantly less time to program than traditional clinically-based programming, while providing similar symptom control. In addition, it is readily available within the clinical DBS programmer, making it a valuable tool for improving current clinical practice.
Glycine receptor β–targeting autoantibodies contribute to the pathology of autoimmune diseases
(2024)
Background and Objectives
Stiff-person syndrome (SPS) and progressive encephalomyelitis with rigidity and myoclonus (PERM) are rare neurologic disorders of the CNS. Until now, exclusive GlyRα subunit–binding autoantibodies with subsequent changes in function and surface numbers were reported. GlyR autoantibodies have also been described in patients with focal epilepsy. Autoimmune reactivity against the GlyRβ subunits has not yet been shown. Autoantibodies against GlyRα1 target the large extracellular N-terminal domain. This domain shares a high degree of sequence homology with GlyRβ making it not unlikely that GlyRβ-specific autoantibody (aAb) exist and contribute to the disease pathology.
Methods
In this study, we investigated serum samples from 58 patients for aAb specifically detecting GlyRβ. Studies in microarray format, cell-based assays, and primary spinal cord neurons and spinal cord tissue immunohistochemistry were performed to determine specific GlyRβ binding and define aAb binding to distinct protein regions. Preadsorption approaches of aAbs using living cells and the purified extracellular receptor domain were further used. Finally, functional consequences for inhibitory neurotransmission upon GlyRβ aAb binding were resolved by whole-cell patch-clamp recordings.
Results
Among 58 samples investigated, cell-based assays, tissue analysis, and preadsorption approaches revealed 2 patients with high specificity for GlyRβ aAb. Quantitative protein cluster analysis demonstrated aAb binding to synaptic GlyRβ colocalized with the scaffold protein gephyrin independent of the presence of GlyRα1. At the functional level, binding of GlyRβ aAb from both patients to its target impair glycine efficacy.
Discussion
Our study establishes GlyRβ as novel target of aAb in patients with SPS/PERM. In contrast to exclusively GlyRα1-positive sera, which alter glycine potency, aAbs against GlyRβ impair receptor efficacy for the neurotransmitter glycine. Imaging and functional analyses showed that GlyRβ aAbs antagonize inhibitory neurotransmission by affecting receptor function rather than localization.
Human startle disease is associated with mutations in distinct genes encoding glycine receptors, transporters or interacting proteins at glycinergic synapses in spinal cord and brainstem. However, a significant number of diagnosed patients does not carry a mutation in the common genes GLRA1, GLRB, and SLC6A5. Recently, studies on solute carrier 7 subfamily 10 (SLC7A10; Asc-1, alanine-serine-cysteine transporter) knock-out (KO) mice displaying a startle disease-like phenotype hypothesized that this transporter might represent a novel candidate for human startle disease. Here, we screened 51 patients from our patient cohort negative for the common genes and found three exonic (one missense, two synonymous), seven intronic, and single nucleotide changes in the 5′ and 3′ untranslated regions (UTRs) in Asc-1. The identified missense mutation Asc-1\(^{G307R}\) from a patient with startle disease and developmental delay was investigated in functional studies. At the molecular level, the mutation Asc-1\(^{G307R}\) did not interfere with cell-surface expression, but disrupted glycine uptake. Substitution of glycine at position 307 to other amino acids, e.g., to alanine or tryptophan did not affect trafficking or glycine transport. By contrast, G307K disrupted glycine transport similar to the G307R mutation found in the patient. Structurally, the disrupted function in variants carrying positively charged residues can be explained by local structural rearrangements because of the large positively charged side chain. Thus, our data suggest that SLC7A10 may represent a rare but novel gene associated with human startle disease and developmental delay.
Background
Medical resource management can be improved by assessing the likelihood of prolonged length of stay (LOS) for head and neck cancer surgery patients. The objective of this study was to develop predictive models that could be used to determine whether a patient's LOS after cancer surgery falls within the normal range of the cohort.
Methods
We conducted a retrospective analysis of a dataset consisting of 300 consecutive patients who underwent head and neck cancer surgery between 2017 and 2022 at a single university medical center. Prolonged LOS was defined as LOS exceeding the 75th percentile of the cohort. Feature importance analysis was performed to evaluate the most important predictors for prolonged LOS. We then constructed 7 machine learning and deep learning algorithms for the prediction modeling of prolonged LOS.
Results
The algorithms reached accuracy values of 75.40 (radial basis function neural network) to 97.92 (Random Trees) for the training set and 64.90 (multilayer perceptron neural network) to 84.14 (Random Trees) for the testing set. The leading parameters predicting prolonged LOS were operation time, ischemia time, the graft used, the ASA score, the intensive care stay, and the pathological stages. The results revealed that patients who had a higher number of harvested lymph nodes (LN) had a lower probability of recurrence but also a greater LOS. However, patients with prolonged LOS were also at greater risk of recurrence, particularly when fewer (LN) were extracted. Further, LOS was more strongly correlated with the overall number of extracted lymph nodes than with the number of positive lymph nodes or the ratio of positive to overall extracted lymph nodes, indicating that particularly unnecessary lymph node extraction might be associated with prolonged LOS.
Conclusions
The results emphasize the need for a closer follow-up of patients who experience prolonged LOS. Prospective trials are warranted to validate the present results.
Highlights
• Loss of DNAJC19's DnaJ domain disrupts cardiac mitochondrial structure, leading to abnormal cristae formation in iPSC-CMs.
• Impaired mitochondrial structures lead to an increased mitochondrial respiration, ROS and an elevated membrane potential.
• Mutant iPSC-CMs show sarcomere dysfunction and a trend to more arrhythmias, resembling DCMA-associated cardiomyopathy.
Background
Dilated cardiomyopathy with ataxia (DCMA) is an autosomal recessive disorder arising from truncating mutations in DNAJC19, which encodes an inner mitochondrial membrane protein. Clinical features include an early onset, often life-threatening, cardiomyopathy associated with other metabolic features. Here, we aim to understand the metabolic and pathophysiological mechanisms of mutant DNAJC19 for the development of cardiomyopathy.
Methods
We generated induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) of two affected siblings with DCMA and a gene-edited truncation variant (tv) of DNAJC19 which all lack the conserved DnaJ interaction domain. The mutant iPSC-CMs and their respective control cells were subjected to various analyses, including assessments of morphology, metabolic function, and physiological consequences such as Ca\(^{2+}\) kinetics, contractility, and arrhythmic potential. Validation of respiration analysis was done in a gene-edited HeLa cell line (DNAJC19tv\(_{HeLa}\)).
Results
Structural analyses revealed mitochondrial fragmentation and abnormal cristae formation associated with an overall reduced mitochondrial protein expression in mutant iPSC-CMs. Morphological alterations were associated with higher oxygen consumption rates (OCRs) in all three mutant iPSC-CMs, indicating higher electron transport chain activity to meet cellular ATP demands. Additionally, increased extracellular acidification rates suggested an increase in overall metabolic flux, while radioactive tracer uptake studies revealed decreased fatty acid uptake and utilization of glucose. Mutant iPSC-CMs also showed increased reactive oxygen species (ROS) and an elevated mitochondrial membrane potential. Increased mitochondrial respiration with pyruvate and malate as substrates was observed in mutant DNAJC19tv HeLa cells in addition to an upregulation of respiratory chain complexes, while cellular ATP-levels remain the same. Moreover, mitochondrial alterations were associated with increased beating frequencies, elevated diastolic Ca\(^{2+}\) concentrations, reduced sarcomere shortening and an increased beat-to-beat rate variability in mutant cell lines in response to β-adrenergic stimulation.
Conclusions
Loss of the DnaJ domain disturbs cardiac mitochondrial structure with abnormal cristae formation and leads to mitochondrial dysfunction, suggesting that DNAJC19 plays an essential role in mitochondrial morphogenesis and biogenesis. Moreover, increased mitochondrial respiration, altered substrate utilization, increased ROS production and abnormal Ca\(^{2+}\) kinetics provide insights into the pathogenesis of DCMA-related cardiomyopathy.
Idiopathic Parkinson’s disease (PD) is characterized by a progredient degeneration of the brain, starting at deep subcortical areas such as the dorsal motor nucleus of the glossopharyngeal and vagal nerves (DM) (stage 1), followed by the coeruleus–subcoeruleus complex; (stage 2), the substantia nigra (SN) (stage 3), the anteromedial temporal mesocortex (MC) (stage 4), high-order sensory association areas and prefrontal fields (HC) (stage 5) and finally first-order sensory association areas, premotor areas, as well as primary sensory and motor field (FC) (stage 6). Autoimmunity might play a role in PD pathogenesis. Here we analyzed whether anti-brain autoantibodies differentially recognize different human brain areas and identified autoantigens that correlate with the above-described dissemination of PD pathology in the brain. Brain tissue was obtained from deceased individuals with no history of neurological or psychiatric disease and no neuropathological abnormalities. Tissue homogenates from different brain regions (DM, SN, MC, HC, FC) were subjected to SDS-PAGE and Western blot. Blots were incubated with plasma samples from 30 PD patients and 30 control subjects and stained with anti-IgG antibodies to detect anti-brain autoantibodies. Signals were quantified. Prominent autoantigens were identified by 2D-gel-coupled mass spectrometry sequencing. Anti-brain autoantibodies are frequent and occur both in healthy controls and individuals with PD. Glial fibrillary acidic protein (GFAP) was identified as a prominent autoantigen recognized in all plasma samples. GFAP immunoreactivity was highest in DM areas and lowest in FC areas with no significant differences in anti-GFAP autoantibody titers between healthy controls and individuals with PD. The anti-GFAP autoimmunoreactivity of different brain areas correlates with the dissemination of histopathological neurodegeneration in PD. We hypothesize that GFAP autoantibodies are physiological but might be involved as a cofactor in PD pathogenesis secondary to a leakage of the blood–brain barrier.
Background
Labelled with lutetium-177, the urea-based small molecules PSMA I&T and PSMA-617 are the two agents most frequently used for radioligand therapy (RLT) in patients with advanced metastatic castration-resistant and prostate-specific membrane antigen (PSMA) expressing prostate cancer (mCRPC). In this matched-pair analysis, we aimed to compare the toxicity and efficacy of both agents for PSMA-directed RLT.
Materials and methods
A total of 110 mCRPC patients from two centres were accrued, 55 individuals treated with [\(^{177}\)Lu]Lu-PSMA I&T, and a matched cohort of 55 patients treated with [\(^{177}\)Lu]Lu-PSMA-617. Matching criteria included age at the first cycle, Gleason score, prostate-specific antigen (PSA) values, and previous taxane-based chemotherapy. Using common terminology criteria for adverse events (CTCAE v. 5.0), toxicity profiles were investigated (including bone marrow and renal toxicity). Overall survival (OS) between both groups was compared.
Results
Toxicity assessment revealed grade III anaemia in a single patient (1.8%) for [\(^{177}\)Lu]Lu-PSMA I&T and five (9.1%) for [\(^{177}\)Lu]Lu-PSMA-617. In addition, one (1.9%) grade III thrombopenia for [\(^{177}\)Lu]Lu-PSMA-617 was recorded. Apart from that, no other grade III/IV toxicities were present. A median OS of 12 months for patients treated with [\(^{177}\)Lu]Lu-PSMA I&T did not differ significantly when compared to patients treated with [\(^{177}\)Lu]Lu-PSMA-617 (median OS, 13 months; P = 0.89).
Conclusion
In this matched-pair analysis of patients receiving one of the two agents most frequently applied for PSMA RLT, the rate of clinically relevant toxicities was low for both compounds. In addition, no relevant differences for OS were observed.
Objectives
To evaluate whether a multimodal intervention in general practice reduces the proportion of second line antibiotic prescriptions and the overall proportion of antibiotic prescriptions for uncomplicated urinary tract infections in women.
Design
Parallel, cluster randomised, controlled trial.
Setting
General practices in five regions in Germany. Data were collected between 1 April 2021 and 31 March 2022.
Participants
General practitioners from 128 randomly assigned practices.
Interventions
Multimodal intervention consisting of guideline recommendations for general practitioners and patients, provision of regional data for antibiotic resistance, and quarterly feedback, which included individual first line and second line proportions of antibiotic prescribing, benchmarking with regional or supra-regional practices, and telephone counselling. Participants in the control group received no information on the intervention.
Main outcome measures
Primary outcome was the proportion of second line antibiotics prescribed by general practices, in relation to all antibiotics prescribed, for uncomplicated urinary tract infections after one year between the intervention and control group. General practices were randomly assigned in blocks (1:1), with a block size of four, into the intervention or control group using SAS version 9.4; randomisation was stratified by region. The secondary outcome was the prescription proportion of all antibiotics, relative within all cases (instances of UTI diagnosis), for the treatment of urinary tract infections after one year between the groups. Adverse events were assessed as exploratory outcomes.
Results
110 practices with full datasets identified 10 323 cases during five quarters (ie, 15 months). The mean proportion of second line antibiotics prescribed was 0.19 (standard deviation 0.20) in the intervention group and 0.35 (0.25) in the control group after 12 months. After adjustment for preintervention proportions, the mean difference was −0.13 (95% confidence interval −0.21 to −0.06, P<0.001). The overall proportion of all antibiotic prescriptions for urinary tract infections over 12 months was 0.74 (standard deviation 0.22) in the intervention and 0.80 (0.15) in the control group with a mean difference of −0.08 (95% confidence interval −0.15 to −0.02, P<0.029). No differences were noted in the number of complications (ie, pyelonephritis, admission to hospital, or fever) between the groups.
Conclusions
The multimodal intervention in general practice significantly reduced the proportion of second line antibiotics and all antibiotic prescriptions for uncomplicated urinary tract infections in women.
Trial registration
German Clinical Trials Register (DRKS), DRKS00020389
Summary
Blood oxygen saturation is an important clinical parameter, especially in postoperative hospitalized patients, monitored in clinical practice by arterial blood gas (ABG) and/or pulse oximetry that both are not suitable for a long-term continuous monitoring of patients during the entire hospital stay, or beyond. Technological advances developed recently for consumer-grade fitness trackers could—at least in theory—help to fill in this gap, but benchmarks on the applicability and accuracy of these technologies in hospitalized patients are currently lacking. We therefore conducted at the postanaesthesia care unit under controlled settings a prospective clinical trial with 201 patients, comparing in total >1,000 oxygen blood saturation measurements by fitness trackers of three brands with the ABG gold standard and with pulse oximetry. Our results suggest that, despite of an overall still tolerable measuring accuracy, comparatively high dropout rates severely limit the possibilities of employing fitness trackers, particularly during the immediate postoperative period of hospitalized patients.
Highlights
•The accuracy of O2 measurements by fitness trackers is tolerable (RMSE ≲4%)
•Correlation with arterial blood gas measurements is fair to moderate (PCC = [0.46; 0.64])
•Dropout rates of fitness trackers during O2 monitoring are high (∼1/3 values missing)
•Fitness trackers cannot be recommended for O2 measuring during critical monitoring
Background
Haemophilus influenzae (Hi) is a Gram-negative bacterium that may cause sepsis or meningitis, treatment of which mainly includes β-lactam antibiotics. Since 2019 EUCAST breakpoints for piperacillin/tazobactam have been available. Little is known about the prevalence and mechanisms of piperacillin/tazobactam resistance in Hi.
Objectives
To provide reliable prevalence data for piperacillin/tazobactam resistance in Hi in Germany, to evaluate different antibiotic susceptibility testing methods and to examine possible resistance mechanisms.
Methods
According to EUCAST breakpoints, the MIC for piperacillin/tazobactam resistance is >0.25 mg/L. All invasive Hi in Germany from 2019 were examined by gradient agar diffusion (GAD) for piperacillin/tazobactam susceptibility. Piperacillin/tazobactam broth microdilution (BMD), piperacillin GAD on tazobactam-containing agar [piperacillin GAD on Mueller–Hinton agar with horse blood (MH-F)/tazobactam) and piperacillin/tazobactam agar dilution (AD) were used for confirmation. Phenotypic testing was complemented by ftsI sequencing.
Results
Piperacillin/tazobactam GAD resulted in 2.9% (21/726) resistant Hi. BMD did not confirm piperacillin/tazobactam resistance. Two strains were found resistant by AD, of which one was also resistant using piperacillin GAD on MH-F/tazobactam. Overall, we found two strains with a piperacillin/tazobactam MIC >0.25 mg/L in at least two different tests (0.3%). Both were β-lactamase-producing amoxicillin/clavulanate-resistant with PBP3 mutations characterized as group III-like+. Relevant PBP3 mutations occurred in six strains without phenotypic piperacillin/tazobactam resistance. These mutations suggest a reduced efficacy of β-lactam antibiotics in these isolates.
Conclusions
Piperacillin/tazobactam resistance prevalence in invasive Hi is low in Germany. Reduced susceptibility was correlated with PBP3 mutations, in particular with group III mutations.
The genomes of both human cytomegalovirus (HCMV) and murine cytomegalovirus (MCMV) were first sequenced over 20 years ago. Similar to HCMV, the MCMV genome had initially been proposed to harbor ≈170 open reading frames (ORFs). More recently, omics approaches revealed HCMV gene expression to be substantially more complex comprising several hundred viral ORFs. Here, we provide a state-of-the art reannotation of lytic MCMV gene expression based on integrative analysis of a large set of omics data. Our data reveal 365 viral transcription start sites (TiSS) that give rise to 380 and 454 viral transcripts and ORFs, respectively. The latter include 200 small ORFs, some of which represented the most highly expressed viral gene products. By combining TiSS profiling with metabolic RNA labelling and chemical nucleotide conversion sequencing (dSLAM-seq), we provide a detailed picture of the expression kinetics of viral transcription. This not only resulted in the identification of a novel MCMV immediate early transcript encoding the m166.5 ORF, which we termed ie4, but also revealed a group of well-expressed viral transcripts that are induced later than canonical true late genes and contain an initiator element (Inr) but no TATA- or TATT-box in their core promoters. We show that viral upstream ORFs (uORFs) tune gene expression of longer viral ORFs expressed in cis at translational level. Finally, we identify a truncated isoform of the viral NK-cell immune evasin m145 arising from a viral TiSS downstream of the canonical m145 mRNA. Despite being ≈5-fold more abundantly expressed than the canonical m145 protein it was not required for downregulating the NK cell ligand, MULT-I. In summary, our work will pave the way for future mechanistic studies on previously unknown cytomegalovirus gene products in an important virus animal model.
Background
Healthcare workers and medical students faced new challenges during the COVID-19 pandemic. Processes within many hospitals were completely disrupted. In addition, the face to face teaching of medical students was drastically reduced. Those at risk of developing mental health problems appear to be younger health care workers and women.
Objective
To investigate potential COVID-19 pandemic-related gender differences in psychological distress among medical students and physicians in their first years of practice.
Design and setting
An anonymous survey was carried out online between December 1, 2021, and March 31, 2022, at the Mannheim Medical Faculty and the Würzburg Medical Faculty, Germany, after obtaining informed consent. Primary outcome measures were changes in anxiety and depression symptoms using the Hospital Anxiety and Depression Scale (HADS), and changes in participants' current quality of life using the WHO Quality of Life BREF.
Results
The results show wave-like courses for perceived anxiety and burden overlapping with the course of the COVID-19 incidence. In comparison to men, women showed a significant higher increase in HADS (p = 0.005) and a reduced life quality (p = 0.007) after COVID-19. Both sexes showed different frequencies of the factors influencing quality of life, with the presence of a previous mental illness and mean anxiety having a significant higher negative impact in women.
Conclusion
Future and young female physicians reported a disproportionate higher burden during COVID-19 compared to their male colleges. These observations suggest an increased need for support and prevention efforts especially in this vulnerable population.
Background
Guideline-directed medical therapy (GDMT) is the cornerstone in the treatment of patients with heart failure and reduced ejection fraction (HFrEF) and novel substances such as sacubitril/valsartan (S/V) and sodium-glucose co-transporter-2 inhibitors (SGLT2i) have demonstrated marked clinical benefits. We investigated their implementation into real-world HF care in Germany before, during, and after the COVID-19 pandemic period.
Methods
The IQVIA LRx data set is based on ∼80% of 73 million people covered by the German statutory health insurance. Prescriptions of S/V were used as a proxy for HFrEF. Time trends were analysed between Q1/2016 and Q2/2023 for prescriptions for S/V alone and in combination therapy with SGLT2i.
Findings
The number of patients treated with S/V increased from 5260 in Q1/2016 to 351,262 in Q2/2023. The share of patients with combination therapy grew from 0.6% (29 of 5260) to 14.2% (31,128 of 219,762) in Q2/2021, and then showed a steep surge up to 54.8% (192,429 of 351,262) in Q2/2023, coinciding with the release of the European Society of Cardiology (ESC) guidelines for HF in Q3/2021. Women and patients aged >80 years were treated less often with combined therapy than men and younger patients. With the start of the COVID-19 pandemic, the number of patients with new S/V prescriptions dropped by 17.5% within one quarter, i.e., from 26,855 in Q1/2020 to 22,145 in Q2/2020, and returned to pre-pandemic levels only in Q1/2021.
Interpretation
The COVID-19 pandemic was associated with a 12-month deceleration of S/V uptake in Germany. Following the release of the ESC HF guidelines, the combined prescription of S/V and SGLT2i was readily adopted. Further efforts are needed to fully implement GDMT and strengthen the resilience of healthcare systems during public health crises.
Electrochemical impedance spectroscopy (EIS) is a valuable technique analyzing electrochemical behavior of biological systems such as electrical characterization of cells and biomolecules, drug screening, and biomaterials in biomedical field. In EIS, an alternating current (AC) power signal is applied to the biological system, and the impedance of the system is measured over a range of frequencies.
In vitro culture models of endothelial or epithelial barrier tissue can be achieved by culturing barrier tissue on scaffolds made with synthetic or biological materials that provide separate compartments (apical and basal sides), allowing for further studies on drug transport. EIS is a great candidate for non-invasive and real-time monitoring of the electrical properties that correlate with barrier integrity during the tissue modeling. Although commercially available transendothelial/transepithelial electrical resistance (TEER) measurement devices are widely used, their use is particularly common in static transwell culture. EIS is considered more suitable than TEER measurement devices in bioreactor cultures that involve dynamic fluid flow to obtain accurate and reliable measurements. Furthermore, while TEER measurement devices can only assess resistance at a single frequency, EIS measurements can capture both resistance and capacitance properties of cells, providing additional information about the cellular barrier's characteristics across various frequencies. Incorporating EIS into a bioreactor system requires the careful optimization of electrode integration within the bioreactor setup and measurement parameters to ensure accurate EIS measurements. Since bioreactors vary in size and design depending on the purpose of the study, most studies have reported using an electrode system specifically designed for a particular bioreactor. The aim of this work was to produce multi-applicable electrodes and established methods for automated non-invasive and real-time monitoring using the EIS technique in bioreactor cultures. Key to the electrode material, titanium nitride (TiN) coating was fabricated on different substrates (materials and shape) using physical vapor deposition (PVD) and housed in a polydimethylsiloxane (PDMS) structure to allow the electrodes to function as independent units. Various electrode designs were evaluated for double-layer capacitance and morphology using EIS and scanning electron microscopy (SEM), respectively. The TiN-coated tube electrode was identified as the optimal choice. Furthermore, EIS measurements were performed to examine the impact of influential parameters related to culture conditions on the TiN-coated electrode system. In order to demonstrate the versatility of the electrodes, these electrodes were then integrated into in different types of perfusion bioreactors for monitoring barrier cells. Blood-brain barrier (BBB) cells were cultured in the newly developed dynamic flow bioreactor, while human umblical vascular endothelial cells (HUVECs) and Caco-2 cells were cultured in the miniature hollow fiber bioreactor (HFBR). As a result, the TiN-coated tube electrode system enabled investigation of BBB barrier integrity in long-term bioreactor culture. While EIS measurement could not detect HUVECs electrical properties in miniature HFBR culture, there was the possibility of measuring the barrier integrity of Caco-2 cells, indicating potential usefulness for evaluating their barrier function. Following the bioreactor cultures, the application of the TiN-coated tube electrode was expanded to hemofiltration, based on the hypothesis that the EIS system may be used to monitor clotting or clogging phenomena in hemofiltration. The findings suggest that the EIS monitoring system can track changes in ion concentration of blood before and after hemofiltration in real-time, which may serve as an indicator of clogging of filter membranes. Overall, our research demonstrates the potential of TiN-coated tube electrodes for sensitive and versatile non-invasive monitoring in bioreactor cultures and medical devices.
Barth Syndrome (BTHS) is an inherited X-chromosomal linked disorder, characterized by early development of cardiomyopathy, immune system defects, skeletal muscle myopathy and growth retardation. The disease displays a wide variety of symptoms including heart failure, exercise intolerance and fatigue due to the muscle weakness. The cause of the disease are mutations in the gene encoding for the mitochondrial transacylase Tafazzin (TAZ), which is important for remodeling of the phospholipid cardiolipin (CL). All mutations result in a pronounced decrease of the functional enzyme leading to an increase of monolysocardiolipin (MLCL), the precursor of mature CL, and a decrease in mature CL itself. CL is a hallmark phospholipid of mitochondrial membranes, highly enriched in the inner mitochondrial membrane (IMM). It is not only important for the formation of the cristae structures, but also for the function of different protein complexes associated with the mitochondrial membrane. Reduced levels of mature CL cause remodeling of the respiratory chain supercomplexes, impaired respiration, defects in the Krebs cycle and a loss of mitochondrial calcium uniporter (MCU) protein. The defective Ca2+ handling causes impaired redox homeostasis and energy metabolism resulting in cellular arrhythmias and defective electrical conduction. In an uncompensated situation, blunting mitochondrial Ca2+ uptake provokes increased mitochondrial emission of H2O2 during workload transitions, related to oxidation of NADPH, which is required to regenerate anti-oxidative enzymes. However, in the hearts and cardiac myocytes of mice with a global knock-down of the Taz gene (Taz-KD), no increase in mitochondrial ROS was observed, suggesting that other metabolic pathways may have compensated for reduced Krebs cycle activation.
The healthy heart produces most of its energy by consuming fatty acids. In this study, the fatty acid uptake into mitochondria and their further degradation was investigated, which showed a switch of the metabolism in general in the Taz-KD mouse model. In vivo studies revealed an increase of glucose uptake into the heart and decreased fatty acid uptake and oxidation. Disturbed energy conversion resulted in activation of retrograde signaling pathways, implicating overall changes in the cell metabolism. Upregulated integrated stress response (ISR) was confirmed by increased levels of the downstream target, i.e., the activating transcription factor 4 (ATF4). A Tafazzin knockout mouse embryonal fibroblast cell model (TazKO) was used to inhibit the ISR using siRNA transfection or pharmaceutical inhibition. This verified the central role of
II
the ISR in regulating the metabolism in BTHS. Moreover, an increased metabolic flux into glutathione biosynthesis was observed, which supports redox homeostasis. In vivo PET-CT scans depicted elevated activity of the xCT system in the BTHS mouse heart, which transports essential amino acids for the biosynthesis of glutathione precursors. Furthermore, the stress induced signaling pathway also affected the glutamate metabolism, which fuels into the Krebs cycle via -ketoglutarate and therefore supports energy converting pathways. In summary, this thesis provides novel insights into the energy metabolism and redox homeostasis in Barth syndrome cardiomyopathy and its regulation by the integrated stress response, which plays a central role in the metabolic alterations. The aim of the thesis was to improve the understanding of these metabolic changes and to identify novel targets, which can provide new possibilities for therapeutic intervention in Barth syndrome.
While there is abounding literature on virus-induced pathology in general and coronavirus in particular, recent evidence accumulates showing distinct and deleterious brain affection. As the respiratory tract connects to the brain without protection of the blood–brain barrier, SARS-CoV-2 might in the early invasive phase attack the cardiorespiratory centres located in the medulla/pons areas, giving rise to disturbances of respiration and cardiac problems. Furthermore, brainstem regions are at risk to lose their functional integrity. Therefore, long-term neurological as well as psychiatric symptomatology and eventual respective disorders cannot be excluded as evidenced from influenza-A triggered post-encephalitic Parkinsonism and HIV-1 triggered AIDS–dementia complex. From the available evidences for coronavirus-induced brain pathology, this review concludes a number of unmet needs for further research strategies like human postmortem brain analyses. SARS-CoV-2 mirroring experimental animal brain studies, characterization of time-dependent and region-dependent spreading behaviours of coronaviruses, enlightening of pathological mechanisms after coronavirus infection using long-term animal models and clinical observations of patients having had COVID-19 infection are calling to develop both protective strategies and drug discoveries to avoid early and late coronavirus-induced functional brain disturbances, symptoms and eventually disorders. To fight SARS-CoV-2, it is an urgent need to enforce clinical, molecular biological, neurochemical and genetic research including brain-related studies on a worldwide harmonized basis.