Ludwig-Maximilians-Universität München

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    Employing the Matrix Element Method with neural networks to search for Higgs pair-production

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    Neural networks (NN) are trained to calculate matrix element weights, with which infor- mation of a measured final-state can be gained via the Matrix Element Method (MEM) theoretical framework. At the same time, the use of NN accelerates the CPU-intensive computations of the matrix element weights, which are used to classify final-states. The predictions of the NN are used as a proof-of-principle to separate Higgs-Higgs (HH) and Higgs-Z (HZ) events. The H H events include final-states coming from super-positions of Higgs self-coupling (tri-H). The matrix element weights are calculated for two different matrix elements, one for HH and one for HZ final states, using simulated data. The separation between these weights is worse for the HZ data than the HH data. Two types of neural networks, feed-forward and convolutional, are examined and trained to predict the HH and HZ matrix elements weights. The computation times are successfully heavily reduced com- pared to the standard calculations of the MEM. Both network types are successful in regards to predicting the HH matrix weights, but they struggle with the weights using the HZ matrix element. To fully understand why the weight separation is worse for HZ data and why the networks have more difficulties with the HZ matrix element would require a deeper investigation into the theoretical framework of the matrix elements, which lies beyond the scope of this research.Neuronale Netze (NN) werden zur Berechnung von Matrixelementgewichten trainiert, um die verfügbare Information eines gemessenen Endzustands im Rahmen der theoretischen Erwartung der Matrix-Element-Methode (MEM) möglichst vollständig zu erfassen und für die Auswertung der Messdaten zu verwenden. Zugleich wird durch den Einsatz von NN die CPU-aufwändige Berechnung der Matrixelementgewichte zur Klassifizierung einzelner Endzustände stark beschleunigt. Dabei werden die Matrixelementvorhersagen des NN als proof-of-principle zunächst zur Klassifizierung und Separierung von HH- und HZ-Ereignissen benutzt. Die HH-Endzusta ̈nden beinhalten, unter anderem, Beiträge von Higgs-Selbstwechselwirkungsdiagrammen (tri-H). Die Matrixelementgewichte werden anhand von simulierten Daten mit zwei verschiedene Matrixelementen berechnet, jeweils für die HH- und die HZ-Endzustände. Die Trennung zwischen den Gewichten ist schlechter für die HZ- als die HH-Ereignisse. Zwei NN-Arten werden untersucht: Feed-forward und Convolutional; diese lernen die HH- und HZ-Matrixelementgewichte vorherzusagen. Eine sehr starke Reduzierung der Rechenzeit im Vergleich zur MEM wird erreicht. Beide Netzarten sind erfolgreich bzgl. der Genauigkeit der HH-Matrixelementgewichten, weisen aber Schwierigkeiten bei den HZ-Matrixelementgewichte auf. Um völlig verstehen zu können, warum die Trennung der Gewichte bei HZ-Ereignissen schlechter ist, und warum die NN bei den HZ-Matrixelementgewichten auf Probleme stoßen, wäre eine tiefere Untersuchung der theoretischen Berechnungen der Matrixelemente notwendig, welches nicht im Rahmen dieser Forschung liegt

    Regulation of PA200 in lung cancer

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    MicroRNA-associated regulatory mechanisms in human mesenchymal stem cells and endothelial cells

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    At the sites of inflammation mesenchymal stem cells (MSCs) are found aiding in tissue repair and immunomodulation. MSCs are in the focus of international research efforts aiming to understand their characteristics and potential for cell- and secretome-based therapeutic applications in the context of various diseases. MSCs migrate from different origin tissues to sites of injury or inflammation in a complex process that involves chemokine-mediated migration and the release of bioactive factors that modulate the behavior of surrounding cells. MicroRNAs (miRNAs) are a class of non-coding RNAs which are pivotal in post-transcriptional regulation of gene expression. Fluctuations in miRNA expression result in changes of protein expression, thereby influencing numerous biological processes and contributing to a variety of human diseases. Additionally, miRNAs can be transferred between cells, thereby regulating gene expression remotely from their cell of origin. It is therefore not surprising that miRNAs modulate major MSC functions such as differentiation, migration and paracrine immunomodulation. The central aim of the habilitation project was ultimately to investigate the role of miRNAs in the process of chemokine-driven migration of MSCs towards sites of inflammation, as well as their paracrine impact on target cells in tumor or atheromatous tissues. Interestingly, although members of the let-7 miRNA family typically function as tumor suppressors by restraining growth and invasion in cancer cells, let-7f appears to exhibit a contrasting role in MSCs. In our studies, we explored how this unique characteristic could potentially prove advantageous in the development of therapeutic approaches. Through four distinct yet complementary studies, we were able to underscore the importance of the miRNA let-7f in MSC biology. Our findings consistently demonstrated that overexpression of let-7f enhances the migratory capacity of MSCs. Let-7f upregulates cell surface receptors such as CXCR4 and FPR2, which in turn improves MSCs migratory response to stimuli like SDF-1 and LL-37. Finally, at the tumor site, MSC-derived exosomes containg let-7f are able to reach and enter the cancer cells exhibiting an anti-tumoral effect. These results were confirmed by in vitro and in vivo results in both glioma and breast cancer tumor models. The aforementioned properties were also evaluated ex vivo using an arterial perfusion model of atherosclerosis in a non-tumoral context. During our studies we also identified a remarkable non-canonical example of miRNA functionality in endothelial cells demonstrating that miR-126-5p inhibits the function of caspase 3 through direct biophysical interaction. This ultimately modulates crucial aspects of cardiovascular biology including the integrity of endothelial cells. These findings were achieved during my postdoctoral tenure in the Department of Clinical Chemistry and Biochemistry, under the direction of Prof. Dr. rer. nat. Marianne Jochum, and at the Institute for Cardiovascular Research (IPEK), led by Prof. Dr. Christian Weber, with mentorship from Prof. Christian Ries at LMU Munich

    Transcriptional analysis of normal and pathological scars

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    Wahrnehmung, Wissensstand und Versorgungssituation von Patientinnen und Patienten mit nicht- berufsbedingtem Handekzem

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    Hintergrund: Ein Handekzem (HE) ist durch eine nicht-ansteckende Entzündung der Haut der Hände gekennzeichnet. Es ist eine häufige Erkrankung mit einer Prävalenz von etwa 10% und weist oft einen chronischen oder rezidivierenden Verlauf auf. Neben genetischen Faktoren sind Kontaktallergien und Feuchtarbeiten als Auslöser für das HE bekannt. Es kann zwischen einem berufsbedingtem HE (B-HE) und nicht-berufsbedingtem HE (NB-HE) unterschieden werden. Für Betroffene mit B-HE gibt es exzellente Versorgungs- und Aufklärungsprogramme, welche über die zuständigen Berufsgenossenschaften angeboten werden. Früherkennung, Hautschutzberatung und Krankheitsaufklärung stehen dabei im Mittelpunkt. Für all die Handekzempatienten und -patientinnen, deren HE nicht durch ihren Beruf ausgelöst ist, sondern zum Beispiel durch Haushaltstätigkeit, wie bei haushaltsführenden oder berenteten Personen, gibt es jenseits der hautärztlichen Konsultation keinerlei Versorgungsprogramme oder Informationsmöglichkeiten. Zielsetzung: Das Ziel dieser Studie war es, Wissensstand, Wahrnehmung und Versorgungssituation von Betroffenen mit NB-HE im Vergleich zu Betroffenen mit B-HE zu untersuchen Methoden: In dieser Studie wurden 131 Patientinnen und Patienten mit NB-HE (Studiengruppe) und 110 Patientinnen und Patienten mit B-HE (Kontrollgruppe) mit Hilfe von Fragebögen befragt. Ergebnisse: -Wissensstand: Etwa der Hälfte der Befragten mit NB-HE war unbekannt, dass „Feuchtarbeit“ einen Auslösefaktor für das Handekzem darstellt und weniger als die Hälfte der NB-HE Befragten konnte „häufiges Händewaschen“ als einen Auslösefaktor für das Handekzem identifizieren. Statistisch signifikant mehr Betroffenen mit B-HE war dieser Zusammenhang von „Feuchtarbeit“ und „häufiges Händewaschen“ und der Entstehung des Handekzems bekannt. „Händedesinfektion“ als Triggerfaktor für das Handekzem konnten statistisch signifikant mehr Betroffene mit B-HE benennen als Betroffene mit NB-HE. B-HE Betroffene, welche an der Hautschutzschulung (HSS) der Berufsgenossenschaften teilgenommen hatten, wiesen insgesamt den höchsten Wissensstand unter allen Studienteilnehmenden auf. Die große Mehrheit von Betroffenen mit B-HE, welche an einer HSS teilgenommen hatten, berichteten, dass die Teilnahme für ein besseres HE-Krankheitsverständnis hilfreich war. - Versorgungssituation: Das durchschnittliche Zeitintervall vom Auftreten der Hautveränderungen bis zu einer ersten ärztlichen Konsultation bei Betroffenen mit NB-HE betrug 20,63 Wochen. Hiervon konsultierten etwa 1/3 der Studienteilnehmenden zunächst eine*n Allgemeinmediziner*in und etwa 2/3 eine Dermatologin oder einen Dermatologen. Mit den Informationen, welche die Betroffenen von ihrer Allgemeinmedizinerin oder ihrem Allgemeinmediziner bzw. ihrer Dermatologin oder ihrem Dermatologen erhielten, waren 24,24% bzw. 27,47% zufrieden. - Wahrnehmung: Mehr als die Hälfte der Befragten mit NB-HE gaben an, ihre Lebensqualität entweder „stark“ oder „ziemlich“ eingeschränkt zu empfinden. Bei Haushaltstätigkeiten fühlten sich etwa 1/3 der Befragten (39,77% der Frauen und 13,89% der Männer) stark eingeschränkt. Unbehaglichkeit aufgrund ihrer Hauterkrankung empfanden etwa 2/3 der weiblichen und die Hälfte der männlichen Studienteilnehmenden. Schlussfolgerung: Unsere Studie bestätigt, dass Betroffene mit NB-HE sich in ihrer Lebensqualität und bei täglichen Aktivitäten stark eingeschränkt fühlen. Das Aussehen der Haut der Hände ist ihnen unangenehm. Es hat sich gezeigt, dass der Wissensstand von Erkrankten mit NB-HE gering ist, was eine adäquate Hautpflege und -Schutz erschwert. Im Gegensatz hierzu wiesen Betroffene mit B-HE einen besseren Wissensstand bezüglich Ätiologie, Prävention und Therapie des HE auf als Betroffene mit NB-HE. Diese Ergebnisse legen nahe, dass die Hautschutzschulungen der Berufsgenossenschaften effektiv sind. Ein langfristiges Ziel ist die Entwicklung von Hautschutzsschulungen auch für Betroffene mit NB-HE.Background: Hand eczema (HE) is a multifactorial disease often related to occupational or household activities. The one-year prevalence of HE is 10% among the general population. It can be distinguished between occupational HE (O-HE) and non-occupational HE (NO-HE). Prevention programs and educational courses in Germany and other countries are only available for O-HE patients and not for patients with NO-HE. It is unclear, to which extent patients with NO-HE are aware of common trigger factors and preventative measures for their hand eczema. Objective: The aim of this study was to gain a better understanding of knowledge, disease perception but also provision of care in NO-HE compared to O-HE patients. Methods: The study was designed as a cross-sectional, questionnaire-based study. Adult patients with NO-HE were eligible to participate (study group). Adult patients diagnosed with O-HE were selected as the control group. Statistical analysis was performed by bilateral analysis using χ²-test. Results: Knowledge: Almost half of the NO-HE patients were unaware of “wet work” being a triggering factor for HE and less than half of the NO-HE patients were able to identify “frequent hand washing” as a trigger for HE. In the O-HE group significantly more patients knew about “wet work” and “frequent hand washing” as risk factors for the development of HE. Significantly more O-HE than NO-HE patients knew about the fact that hand sanitizing can be less disruptive for the skin barrier than hand washing. O-HE patients who had previously participated in skin protection seminars (SPS) were found to be more knowledgeable about HE in general. Provision of care: The average time interval from the first occurrence of skin lesions until consulting a physician was 20.63 weeks. Regardless of whether the patients consulted a family physician or a dermatologist first with their skin lesions, only one out of four patients stated to be satisfied with the provided information about the HE. Perception: More than half of the patients consider their quality of life either strongly or fairly impaired due to HE. Two third of the females and almost half of the males felt either “strongly” or “fairly” uncomfortable due to their hand eczema. Conclusion: Our study confirms that patients with HE feel strongly restricted in their quality of life or daily activities and embarrassed about their skin appearance on the hands. We found that the level of knowledge and understanding of hand eczema in NO-HE patients is low, which makes adequate protection of the skin and adherence to treatment difficult for them. In contrast to this, O-HE patients were found to have a better HE knowledge regarding aetiology, prevention measures and treatment strategies in hand eczema than NO-HE patients. This suggests that the educational courses, provided by the employers´ liability insurance in Germany are effective. Following this example, a long-term objective should be the development of educational intervention seminars/ SPS also for NO-HE patients

    Strongly interacting phenomena in synthetic quantum systems

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    Prognostische und therapiebezogene Einflüsse der gesundheitsbezogenen Lebensqualität beim Prostatakarzinom

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    DM-IMT - Kontrollierte, randomisierte, dreiarmige Interventionsstudie zur Sicherheit und Effektivität des regelmäßigen Atemmuskeltrainings bei Patienten mit Myotoner Dystrophie Typ 1

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    Myotonic dystrophy type 1 is an autosomal dominant CTG trinucleotide disorder and counts as one of the most common hereditary muscle diseases with myotonia in adults. During the course of the disease, many patients develop a significant respiratory muscle weakness with progressive respiratory insufficiency, often leading to reduced quality of life, the need for mechanical ventilation and even death. There is currently no causal therapy for patients with DM1, so new approaches to alleviate symptoms and improve quality of life and participation are essential. The DM-IMT study is designed to provide the first relevant findings on the safety and effectiveness of regular respiratory muscle training for patients with DM1 and to enable a possible integration into future care and therapy recommendations for DM1 patients. This controlled, randomised, three-arm intervention trial enrolled 26 patients with confirmed DM1 and assigned them to one of three groups: inspiratory strength training, endurance training or no respiratory muscle training as a control group. Regular follow-up examinations were carried out to analyse changes in lung function parameters, blood gas analysis, muscular function tests, and impacts on life quality and muscle function in daily life. The study duration was nine months per participant, and data were collected from October 2019 to September 2020. The analysis of these data showed promising significant improvements in important lung function parameters. A significant improvement in maximal inspiratory pressure MIP was observed in both training groups, and the endurance training group also showed a significant increase in maximal voluntary ventilation MVV and a relevant improvement in forced vital capacity FVC. The results of the questionnaires used to identify and describe symptoms relevant to daily life did not show the same improvements as the lung function parameters. Still, a developed final questionnaire indicated a subjectively noticed improvement in the majority of participants. The stabilisation and improvement of important lung function parameters, positive effects on daily performance and the absence of relevant side effects support the achievement of the primary objective of the DM-IMT respiratory muscle study. The existing willingness to train and adequate compliance of this DM1 cohort suggest that the establishment of regular respiratory muscle training can be accepted and reliably performed by most patients. Due to relevant restrictions and appointment cancellations caused by the COVID-19 pandemic, corresponding analyses could not be carried out to the planned extent, and no statements about the temporal progression of the effects could be made. In summary, similar positive effects have been demonstrated compared to previous RMT studies for other neuromuscular disorders with slowly progressive respiratory muscle weakness. Regular respiratory muscle training appears useful, effective, and has low side effects for patients with myotonic dystrophy type 1. It may contribute to the stabilisation or improvement of diaphragm strength, as measured by maximum inspiratory pressure, and thus slowing down the progression of respiratory insufficiency. These reasons justify the goal of including respiratory muscle training in new care and therapy recommendations for symptom relief and disease progression retardation. However, further larger prospective studies are necessary to validate the long-term clinical benefits of these results and to refine and specify the formulation of these recommendations. Therefore, the scope could be to identify the time period, after which a significant effect can be expected from exercise and how to maintain this effect after stopping or interrupting regular respiratory muscle training. Furthermore, it should be clearly defined which type of training is most appropriate for which patients and whether the effect can be further enhanced by possible combinations of strength and endurance training and inspiratory and expiratory training

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    Digitale Hochschulschriften der LMU
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