22455 research outputs found
Sort by
Morbus Perthes - prognostische Faktoren und ihre Auswirkungen auf das klinische und radiologische Endergebnis
Get PDF
Next-generation mass spectrometry for clinical and spatial proteomics
Get PDFWhile DNA provides the blueprint, proteins represent the functional and biologically active units of a cell. As such the proteome is our closest proxy to the phenotype, and can give important insights into cellular function and disease pathology. Although other approaches exist, mass spectrometry (MS) based proteomics remains the method of choice for fast, sensitive, quantitative, and high-throughput analysis of proteins. Over the years, MS-based proteomics has seen great advancements and now enables the routine analysis of thousands of clinical samples, near full proteomes and even single cells. A key factor in these advancements are innovations in MS technology that enable the instruments to push the boundaries of sensitivity, resolution, and acquisition speed. In this thesis I therefore first focus on evaluating MS technologies and optimizing MS acquisition strategies to expand the usability of MS instruments, and second to apply them to clinical and spatial proteomics.
Across the MS workflow, one can greatly improve performance by implementing novel technology, optimizing acquisition strategies and improving data analysis. In a first project, I evaluated the full mass range application of ΦSDM, a computational alternative to standard MS signal processing. By providing a two-fold increase in resolution or acquisition speed, as well as greatly improving signal-to-noise ratio, I showed that ΦSDM could be a useful addition to extend the potential of existing Orbitrap mass spectrometers for a wide range of proteomics applications. I then optimized a high-throughput acquisition strategy for plasma proteomics on a state-of-the-art LC/MS setup, which we applied to studying the effects of muscle loss in individuals undergoing bedrest in a study funded by the Italian Space Agency. While follow up is needed, the study identifies a potential biomarker candidate associated with muscle maintenance. To fully make use of the data obtained with state-of-the-art MS instruments and ever more complex data acquisition strategies, I contributed to benchmarking AlphaDIA, a modular, open-source framework for data independent acquisition data analysis developed in our lab.
I next contributed to applying novel MS technology for low input proteomics. The Orbitrap Astral, as well as other highly-sensitive TOF detector instruments have pushed the boundaries of sensitivity, acquisition speed and identification. This has shown to be particularly advantageous for low input applications such as Deep Visual Proteomics (DVP). Through a combination of these ultra-high sensitivity MS instruments, and tailored DIA acquisition strategies, we were able to decrease the required cell input amount and broaden the range of application for DVP. Focusing first on tissues from a single patient with signet ring cell carcinoma, we showcased the potential of DVP for personalized medicine and were able to propose a treatment option that effectively halted tumor progression. We next evaluated the phenotypic shifts after xenotransplantation of organoid models. In a human mucosa model, we could show that xenotransplanted tissue was closer to human physiology and regained its functional profile in comparison to in-vitro organoid cultures and could provide valuable insights into human disease. Lastly, we extended the previously described single cell DVP workflow to formalin-fixed paraffin-embedded tissue, and applied it to study proteotoxic stress in alpha-1-antitrypsin deficiency. Using a tailored MS method with optimized variable DIA isolation windows, we were able to identify up to 3800 protein groups from a single hepatocyte shape, which is the equivalent to ~half of a full cell.
In summary, my thesis highlights how a combination of technical, methodological, and computational improvements can help to advance MS-based proteomics and bridge the gap to clinical applications and personalized medicine
Feasibility and clinical efficacy of repetitive neuromuscular magnetic stimulation in pediatric headache
Get PDFIntroduction: Pediatric primary headache disorders, including migraine, tension-type headache (TTH) and their mixed-type pose a significant burden on young individuals. Post-traumatic headache (PTH) is also to be emphasized as a secondary headache disorder due to its prevalence. Depending on frequency and severity of individual attacks, these headache disorders can represent a considerable burden. After we found repetitive neuromuscular magnetic stimulation (rNMS) to be safe, feasible and well accepted in young adults, in this analysis safety, feasibility, acceptance as well as clinical impact in the pediatric age group („first-in-child“) are retrospectively assessed.
Materials and Methods: A cohort of n=33 children and adolescents who received n=182 rNMS sessions in a clinical setting are retrospectively analyzed regarding feasibility and effectiveness of rNMS targeting the upper trapezius muscle (UTM). Various parameters, including intensity and frequency of treatment, safety, central and muscular effects, and factors affecting the level of response are evaluated.
Results: The project findings suggest that rNMS holds promise as a point-of-care nonpharmacological neuromodulation approach for pediatric headache disorders. It demonstrates that rNMS is practically feasible, safe, well-accepted (No adverse events in 76.8% of sessions, 94.7% of patients would undergo the treatment again, 85.3% would recommend the treatment). Therapeutically groundbreaking, the treatment seems to be associated with a significant reduction in headache frequency and intensity. Especially in PTH patients muscular hypersensitivity was reduced, and the reduction sustained until the follow-up assessment 3 months later. Neck pain then also emerged as a factor positively influencing the response to rNMS.
Conclusion: Repetitive neuromuscular magnetic stimulation (rNMS) offers a new, nonpharmacological and personalized treatment option for children and adolescents with headache disorders as it was found to be safe, feasible, and highly accepted. In principle, rNMS appears to have a positive impact on headache symptoms - irrespective of the specific ICHD-3 diagnosis. Patients with neck pain seem biologically plausible to be particularly responsive which can be conceptually related to neuromodulation of central nociceptive processing within the trigemino-cervical complex. Despite clear limitations, this analysis provides a foundation for future research and the potential integration of rNMS into a multimodal regimen for pediatric headache disorders. Larger controlled studies are warranted to confirm and potentially develop the efficacy and utility of rNMS in this population further
Elucidating the roles of ScORF3 and VAT-1 in Neocarzilin A biosynthesis and anticancer activity: a structural and functional study
Get PDFDie VSB® bei Patienten mit Gehörgangsatresie: Längerfristige audiologische Auswirkungen und Ergebnisse der Lebensqualität
Get PDFThe aim of this study was to evaluate the effectiveness and acceptance especially in the long-term with the active middle ear implant system Vibrant Soundbridge (VSB, MED-EL, Austria) in patients with aural atresia.
With 51 subjects and a maximum follow-up period of 155 months (x̅=52.9 ± 33.2 months) this study presents the currently largest collection of patients with aural atresia and audiometric long-term results.
The personal data and the audiometric results of the regular follow-up visits were evaluated in 51 patients who received a VSB implant between 2009 and 2019 in the Department of Otolaryngology at Ludwig-Maximilans-Universitätsklinikum Großhadern. The mean age of the study population at implantation was 13.9 years (SD=11.3), 42 patients (79.2 %) were children and adolescents and 11 patients (20.8 %) had reached adulthood. The follow-up period ranged from 1 to 155 months with a mean of 52.9 months or 4.0 years. The benefit of the VSB was evaluated by hearing tests (AC threshold, wobble tones), speech-tests (Freiburger Einsilbertest and Oldenburger Satztest) and by questionnaire (Speech, Spatial and Qualities of Hearing Scale). The results showed a significant improvement in hearing and speech comprehension after implantation in all test methods used. The values also remained largely constant over the long term, indicating a sustained functional gain of the VSB. The results of the questionnaire affirm the positive influence on the hearing and speech comprehension with the VSB.
These results affirm the claim for using the active middle ear implant VSB as early as possible for patients with aural atresia
