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Atypical Hemolytic Uremic Syndrome/Complement-Mediated Thrombotic Microangiopathy Triggered by SARS-CoV-2 Infection: A Case Report
No full textIntroduction: Atypical hemolytic uremic syndrome (aHUS), commonly considered the prototypical form of complement-mediated thrombotic microangiopathy, is caused by dysregulated complement activation, often triggered by genetic mutations and external factors. We present a case of aHUS occurring 1 month after SARS-CoV-2 infection in a patient with a mutation in the complement factor H (CFH), a primary regulator of the alternative complement pathway. Case Presentation: A 41-year-old woman with no prior conditions developed acute kidney injury, hemolytic anemia, and thrombocytopenia 1 month after SARS-CoV-2 infection. Genetic testing identified a pathogenic CFH variant (c.3572C>T), and kidney biopsy confirmed thrombotic microangiopathy. Treatment with plasma exchange, corticosteroids, and C5 inhibitors led to remission of proteinuria and improved renal function within 2 months, avoiding dialysis. Even a second SARS-CoV-2 infection 6 months after the onset of aHUS and under continuous complement C5 inhibition did not result in further kidney damage. Conclusions: Our case report is consistent with observations made by several groups that SARS-CoV-2 infection may trigger aHUS in genetically predisposed individuals. Early diagnosis and complement-targeted therapy are crucial to prevent severe outcomes
Beyond oscillations—Toward a richer characterization of brain states
No full textOur moment-to-moment conscious experience is paced by transitions between states, each one corresponding to a change in the electromagnetic brain activity. One consolidated analytical choice is to characterize these changes in the frequency domain, such that the transition from one state to the other corresponds to a difference in the strength of oscillatory power, often in pre-defined, theory-driven frequency bands of interest. Nonetheless, recent computational advances allow us to explore new ways to characterize electromagnetic brain activity and its changes. Here, we assembled a set of multiple transformations aiming to describe time series in a multidimensional feature space. On an MEG dataset with 29 human participants, we tested how the features extracted in this way described some of those state transitions known to elicit prominent changes in the frequency spectrum, such as eyes-closed versus eyes-open resting-state or the occurrence of visual stimulation. We then compared the informativeness of multiple sets of features by submitting them to a multivariate classifier (SVM). We found that the new features outperformed traditional ones in generalizing states classification across participants. Moreover, some of these new features yielded systematically better decoding accuracy than the power in canonical frequency bands that has been often considered a landmark in defining these state changes. Critically, we replicated these findings, after pre-registration, in an independent EEG dataset (N = 210). In conclusion, the present work highlights the importance of enriching our perspective on the characteristics of electromagnetic brain activity, by considering other features of the signal on top of power in theory-driven frequency bands of interest
Combination of differently structured pump beams for selective mode excitation
No full textDigital micromirror devices (DMD) enable the flexible and selective excitation of transverse resonator modes through spatial gain shaping. With the aim to increase the output power limited by the DMD damage threshold, a pump beam combining approach was investigated. One pump beam was shaped by a DMD, such that a gain distribution adapted to a target mode was realized, whereas a second pump beam provided additional but mode-unspecific gain for a wide range of transverse modes. Although the second pump beam allowed to reduce the power incident on the DMD by a factor of three to five, output power scaling could also be achieved by adapting the mode-like pattern displayed on the DMD instead. Still, modal analysis of the observed multi-mode lasing revealed characteristic properties of pump distributions adapted to Hermite-Gaussian HGm,0 modes: a center-heavy pump distribution at first distinctly excites the target mode and eventually low-order modes, whereas an eccentric pump distribution reduces the lasing threshold at the expense of distinction to the neighboring modes
Cortisol and periodontitis: Prospective observational and Mendelian randomization studies
No full textPurpose: Cortisol has obesogenic, hyperglycemic and immunomodulating effects. Preclinical and observational research suggested that it is associated with periodontitis but the evidence for potential causality in humans is sparse. We triangulated results from prospective observational and Mendelian randomization (MR) analyses to further explore this. Methods: Using pooled data from 3,388 participants of two population cohort studies embedded in the Study of Health in Pomerania (SHIP) project, we associated serum cortisol levels with periodontal outcomes measured after a median follow-up time of 6.9 years, adjusting for confounding and selection bias using propensity score weighting and multiple imputation. We further examined the effect of genetically proxied plasma morning cortisol levels on periodontitis using two-sample MR of 17,353 cases and 28,210 controls. Results: In SHIP, we found that cortisol levels were positively associated with follow-up levels of mean clinical attachment level (CAL), deep interdental CAL and bleeding on probing but were unrelated to mean probing pocket depth and deep periodontal pockets. In MR analysis, cortisol was not associated with periodontitis.
Conclusion: The observational study revealed a prospective association of spot cortisol with makers of periodontitis. Contrary to observational studies, genetically instrumented, long-term cortisol was unrelated to periodontitis. Our results find no univocal evidence that cortisol plays a role in periodontitis pathology, casting doubt on cortisol-related pathways
Data Literacy in Zeiten von Big Data und STEAM:Ein Blick auf das Zusammenspiel der Teilkompetenzen 'Datenerhebung' und 'Datenauswertung' im Rahmen einer transdisziplinären Bildung
No full textIn einer digitalisierten Gesellschaft ist der kompetente Umgang mit Daten von großer Bedeutung. Data Literacy umfasst das reflektierte Erheben, Organisieren, Auswerten und Kommunizieren von Daten und sollte ab der frühkindlichen Bildung gefördert werden. Mittels Design-Based Research untersucht diese Dissertation den Einfluss der eigenständigen Datenerhebung durch Jugendliche auf den reflektierten Umgang mit Daten und stellt ein transdisziplinäres Lehrkonzept für den Sekundarbereich vor, welches entwickelt, erprobt und evaluiert wurde. Die Ergebnisse zeigen: (i) eine eigenständige Datenerhebung steigert die reflektierte Auswertung eines Datensatzes, (ii) Technologien wie immersive virtuelle Realität und Mikrocontroller unterstützen den Prozess, (iii) eine transdisziplinäre Projektwoche zum Thema Mobilitätswende kann die Selbstwirksamkeit der Lernenden hinsichtlich eines reflektierten Umgangs mit Daten erhöhen
Examining the neural correlates of visual and auditory consciousness using a multimodal inattentional unawareness paradigm
No full textJeden Tag erreichen unzählige Sinneseindrücke unser Gehirn.
Nur ein Bruchteil davon wird bewusst wahrgenommen. Die neuronalen
Mechanismen, die diesem Bewusstsein zugrunde liegen, werden als neuronale Korrelate des Bewusstseins (NCC) zusammengefasst. NCC sind seit Jahrzehnten Gegenstand neurowissenschaftlicher Forschung (Mashour et al. 2020, MacLean et al. 2023). Die visuellen NCC standen bisher im Mittelpunkt der Forschung, aber auch andere Modalitäten werden zunehmend untersucht (Schlossmacher et al. 2020, Dellert et al. 2021). Bei den bisherigen Studien handelt es sich in der Regel um unimodale Studien. Da die Theorien über NCC jedoch ähnliche neuronale Mechanismen in allen Modalitäten annehmen (Dehaene et al. 2014, 2006), ist es sinnvoll, NCC beider Modalitäten gleichzeitig in einem einzigen Experiment zu untersuchen. Daher verfolgt diese Studie einen multimodalen Ansatz; das auditorische und visuelle System werden innerhalb eines Versuchsaufbaus mittels fMRT untersucht
Flexible Syndesmotic Reconstruction with Two Suture Buttons Provides Equal Stability Compared to Syndesmotic Screws: A Biomechanical Study
No full textBackground: This study investigated syndesmotic stability after transection and the effects of stabilization using rigid and dynamic reconstruction techniques. Methods: Syndesmotic stability was analyzed using a six-degree-of-freedom robotic arm on 14 human specimens. Stability was analyzed in the neutral position and during dorsiflexion and plantar flexion using an external rotation stress test under an axial load of 200 Newtons. The examination was performed on intact and sequentially transected syndesmosis in the following order: (1) anterior inferior tibiofibular ligament (AITFL); (2) interosseous ligament (IOL); and (3) posterior inferior tibiofibular ligament (PITFL). Then, reconstruction was performed using different syndesmotic screw techniques or a dynamic Suture Button system (Arthrex TightRope; n = 7). Results: A syndesmotic transection mainly caused sagittal instability of the fibula. While both static and dynamic reconstruction provided stabilization, screw fixation, particularly with two screws and a plate, demonstrated superior control of the fibular movement, especially in the sagittal and transverse planes, compared to one Suture Button. Conclusions: The results suggest that syndesmotic stabilization with one Suture Button may be insufficient for cases involving three-ligamentous injuries, whereas two Suture Buttons may offer comparable biomechanical stability to syndesmotic screws. Additionally, the study suggests that lateral radiographs may provide additional clinical value in assessing syndesmotic stability
