@phdthesis{Adhikari2024,
  author    = {Adhikari, Bikash},
  title     = {Targeted degradation of Myc-interacting oncoproteins},
  doi       = {10.25972/OPUS-31732},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-317326},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {The hallmark oncoprotein Myc is a major driver of tumorigenesis in various human cancer entities. However, Myc's structural features make it challenging to develop small molecules against it. A promising strategy to indirectly inhibit the function of Myc is by targeting its interactors. Many Myc-interacting proteins have reported scaffolding functions which are difficult to target using conventional occupancy- driven inhibitors. Thus, in this thesis, the proteolysis targeting chimera (PROTAC) approach was used to target two oncoproteins interacting with Myc which promote the oncogenicity of Myc, Aurora-A and WDR5. PROTACs are bifunctional small molecules that bind to the target protein with one ligand and recruit a cellular E3- ligase with the other ligand to induce target degradation via the ubiquitin- proteasome system. So far, the most widely used E3-ligases for PROTAC development are Cereblon (CRBN) and von Hippel-Lindau tumor suppressor (VHL). Furthermore, there are cases of incompatibility between some E3-ligases and proteins to bring about degradation. Hence there is a need to explore new E3- ligases and a demand for a tool to predict degradative E3-ligases for the target protein in the PROTAC field. In the first part, a highly specific mitotic kinase Aurora-A degrader, JB170, was developed. This compound utilized Aurora-A inhibitor alisertib as the target ligand and thalidomide as the E3-ligase CRBN harness. The specificity of JB170 and the ternary complex formation was supported by the interactions between Aurora-A and CRBN. The PROTAC-mediated degradation of Aurora-A induced a distinct S- phase defect rather than mitotic arrest, shown by its catalytic inhibition. The finding demonstrates that Aurora-A has a non-catalytic role in the S-phase. Furthermore, the degradation of Aurora-A led to apoptosis in various cancer cell lines. In the second part, two different series of WDR5 PROTACs based on two protein- protein inhibitors of WDR5 were evaluated. The most efficient degraders from both series recruited VHL as a E3-ligase and showed partial degradation of WDR5. In addition, the degradation efficiency of the PROTACs was significantly affected by the linker nature and length, highlighting the importance of linker length and composition in PROTAC design. The degraders showed modest proliferation defects at best in cancer cell lines. However, overexpression of VHL increased the degradation efficiency and the antiproliferative effect of the PROTACs. In the last part, a rapamycin-based assay was developed to predict the degradative E3-ligase for a target. The assay was validated using the WDR5/VHL and Aurora- A/CRBN pairs. The result that WDR5 is degraded by VHL but not CRBN and Aurora-A is degraded by CRBN, matches observations made with PROTACs. This technique will be used in the future to find effective tissue-specific and essential E3-ligases for targeted degradation of oncoproteins using PROTACs. Collectively, the work presented here provides a strategy to improve PROTAC development and a starting point for developing Aurora-A and WDR5 PROTACs for cancer therapy.},
  subject      = {Degradation},
  language  = {en}
}
@phdthesis{Dekant2024,
  author    = {Dekant, Raphael H.},
  title     = {Species-differences in the \(in\) \(vitro\) biotransformation of trifluoroethene (HFO-1123)},
  doi       = {10.25972/OPUS-31403},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-314035},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {1,1,2-trifluoroethene (HFO-1123) is intended for use as a refrigerant. Inhalation studies on HFO-1123 in rats suggested a low potential for toxicity, with no-observed-adverse-effect levels greater then 20,000 ppm. However, single inhalation exposure of Goettingen Minipigs and New Zealand White Rabbits resulted in mortality. It was assumed that conjugation of HFO-1123 with glutathione, via glutathione S-transferase, gives rise to S-(1,1,2-trifluoroethyl)-L-glutathione (1123-GSH), which is then transformed to the corresponding cysteine S-conjugate (S-(1,1,2-trifluoroethyl)-L-cysteine, 1123-CYS). Subsequent beta-lyase mediated cleavage of 1123-CYS may result in monofluoroacetic acid, a potent inhibitor of aconitase. Species-differences in 1123-GSH formation and 1123-CYS cleavage to MFA may explain species-differences in HFO-1123 toxicity. This study was designed to test the hypothesis, that GSH-dependent biotransformation and subsequent beta-lyase mediated formation of monofluoroacetic acid, a potent inhibitor of aconitase in the citric acid cycle, may play a key role in HFO-1123 toxicity and to evaluate if species-differences in the extent of MFA formation may account for the species-differences in HFO-1123 toxicity. The overall objective was to determine species-differences in HFO-1123 biotransformation in susceptible vs. less susceptible species and humans as a basis for human risk assessment. To this end, in vitro biotransformation of HFO-1123 and 1123-CYS was investigated in renal and hepatic subcellular fractions of mice, rats, humans, Goettingen Minipigs and NZW Rabbits. Furthermore, cytotoxicity and metabolism of 1123-CYS was assessed in cultured renal epithelial cells. Enzyme kinetic parameters for beta-lyase mediated cleavage of 1123-CYS in renal and hepatic cytosolic fractions were determined, and 19F-NMR was used to identify fluorine containing metabolites arising from 1123-CYS cleavage. Quantification of 1123-GSH formation in hepatic S9 fractions after incubation with HFO-1123 was performed by LC-MS/MS and hepatic metabolism of HFO-1123 was monitored by 19F-NMR. Rates of 1123-GSH formation were increased in rat, mouse and NZW Rabbit compared to human and Goettingen hepatic S9, indicating increased GSH dependent biotransformation in rats, mouse and NZW Rabbits. NZW Rabbit hepatic S9 exhibited increased 1123-GSH formation in the presence compared to the absence of acivicin, a specific gamma-GT inhibitor. This indicates increased gamma-GT mediated cleavage of 1123-GSH in NZW Rabbit hepatic S9 compared to the other species. 19F-NMR confirmed formation of 1123-GSH as the main metabolite of GSH mediated biotransformation of HFO-1123 in hepatic S9 fractions next to F-. Increased F- formation was detected in NZW Rabbit and Goettingen Minipig hepatic S9 in the presence of an NADPH regenerating system, indicating a higher rate of CYP-450 mediated metabolism in these species. Based on these findings, it is possible that CYP-450 mediated metabolism may contribute to HFO-1123 toxicity. In contrast to the increased formation of 1123-GSH in rat, mouse and NZW Rabbit hepatic S9 (compared to human and Goettingen Minipig), enzyme kinetic studies revealed a significantly higher beta-lyase activity towards 1123-CYS in renal cytosol of Goettingen Minipigs compared to cytosol from rats, mice, humans and NZW Rabbits. However, beta-lyase cleavage in renal NZW Rabbit cytosol was slightly increased compared to rat, mouse and human renal cytosols. 19F-NMR analysis confirmed increased time-dependent formation of MFA in renal Goettingen Minipig cytosol and NZW Rabbit (compared to human and rat cytosolic fractions). Three structurally not defined MFA-derivatives were detected exclusively in NZW Rabbit and Goettingen Minipig cytosols. Also, porcine kidney cells were more sensitive to cytotoxicity of 1123-CYS compared to rat and human kidney cells. Overall, increased beta-lyase mediate cleavage of 1123-CYS to MFA in Goettingen Minipig and NZW Rabbit kidney (compared to human and rat) may support the hypothesis that enzymatic cleavage by beta-lyases may account for the species-differences in HFO-1123 toxicity. However, the extent of GST mediated biotransformation in the liver as the initial step in HFO-1123 metabolism does not fully agree with this hypothesis, since 1123-GSH formation occurs at higher rates in rat, mouse and NZW Rabbit S9 as compared to the Goettingen Minipig. Based on the inconsistencies between the extent of GST and beta-lyase mediated biotransformation of HFO-1123 obtained by this study, a decisive statement about an increased biotransformation of HFO-1123 in susceptible species with a direct linkage to the species-specific toxicity cannot be drawn. Resulting from this, a clear and reliable conclusion regarding the risk for human health originating from HFO-1123 cannot be made. However, considering the death of Goettingen Minipigs and NZW Rabbits after inhalation exposure of HFO-1123 at concentrations great than 500 ppm and greater than 1250 ppm, respectively, this indicates a health concern for humans under peak exposure conditions. For a successful registration of HFO-1123 and its use as a refrigerant, further in vitro and in vivo investigations addressing uncertainties in the species-specific toxicity of HFO-1123 are urgently needed.},
  subject      = {Biotransformation},
  language  = {en}
}
@phdthesis{Hajduk2024,
  author    = {Hajduk, Maurice Martin},
  title     = {Darf es etwas mehr sein? Neuroenhancement im Studium - eine Befragung an W{\"u}rzburger Hochschulen},
  doi       = {10.25972/OPUS-35981},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359812},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Neuroenhancement (NE) bezeichnet die Einnahme psychotroper Substanzen mit dem Ziel der geistigen Leistungssteigerung oder Beruhigung. NE wird durch gesunde Perso- nen genutzt. Es besteht somit keine Indikation zur Einnahme psychotroper Wirkstoffe. Zum NE genutzte Substanzen sind z.B. Koffeintabletten, verschreibungspflichtige Medi- kamente oder illegale Substanzen. Die bisherige Forschung findet Hinweise auf einen Zusammenhang zwischen NE und ADHS-Symptomen, einigen Aspekten psychischer Gesundheit, sowie Substanzkonsum. Bisher gibt es keine Forschung zu NE am Hoch- schulstandort W{\"u}rzburg. Es wurde eine anonyme online Querschnittsbefragung im ersten Quartal 2021 durchge- f{\"u}hrt. Eingeladen waren 5600 Studierende der Julius-Maximilians-Universit{\"a}t W{\"u}rzburg und der Hochschule f{\"u}r angewandte Wissenschaften W{\"u}rzburg Schweinfurt. Der Frage- bogen bestand aus 53 Items und enthielt u. a. die folgenden validierten Messinstrumente: ASRS, PSS-10, PHQ-4 und AUDIT-C. Die Response Rate lag bei 18\% (n = 1011). Das Wissen {\"u}ber NE war weit unter den Stu- dierenden verbreitet. Die Pr{\"a}valenz f{\"u}r Neuroenhancement im Studium lag bei 12.7\%. Die drei meistgenannten Substanzen waren Koffeintabletten (6.6\%), Cannabis (4.5\%) und Methylphenidat (4.3\%). H{\"a}ufigster Anlass f{\"u}r NE war die Pr{\"u}fungsvorbereitung. Es zeigten sich deutliche Unterschiede zwischen den Fachbereichen, u.a. hinsichtlich der Pr{\"a}valenz von NE. ADHS-Symptomen, Stress, {\"A}ngstlichkeit, und Depressivit{\"a}t waren positiv mit NE assoziiert. Ein st{\"a}rkerer Effekt ergab sich f{\"u}r den Zusammenhang zwi- schen NE und riskanten Alkoholkonsum bzw. Tabakkonsum. Diese Ergebnisse wurden durch eine binomial logistische Regression best{\"a}tigt. Die konsumierten Substanzen, das Wissen {\"u}ber NE, die Pr{\"a}valenz von NE und die Gr{\"u}nde f{\"u}r dessen Nutzung f{\"u}gen sich nahtlos in die bisherige Forschung ein. Auch die Assoziation zwischen ADHS-Symptomen, Stress, {\"A}ngstlichkeit, Depressivit{\"a}t, riskan- tem Alkoholkonsum und Tabakkonsum best{\"a}tigt bisherige Forschungsergebnisse. Es konnte gezeigt werden, dass rund ein Zehntel der Studierenden NE bereits genutzt haben. In Anbetracht der gesundheitlichen Gefahren, die mit NE einhergehen ist die Etab- lierung bzw. der Ausbau von Aufkl{\"a}rung-, Beratungs- und Hilfsangeboten f{\"u}r Studie- rende anzustreben sowie weitere Forschung zum Thema indiziert.},
  subject      = {Psychische Gesundheit},
  language  = {de}
}
@phdthesis{Friedrich2024,
  author    = {Friedrich, Anna-Lena},
  title     = {FoxO3-mediated, inhibitory effects of CNP on the profibrotic activation of lung fibroblasts},
  doi       = {10.25972/OPUS-35984},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359845},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Idiopathic Pulmonary Fibrosis (IPF) is a progressive parenchymal lung disease with limited therapeutic treatments. Pathologically altered lung fibroblasts, called myofibroblasts, exhibit increased proliferation, migration, and collagen production, and drive IPF development and progression. Fibrogenic factors such as Platelet derived growth factor-BB (PDGF-BB) contribute to these pathological alterations. Endogenous counter-regulating factors are barely known. Published studies have described a protective role of exogenously administered C-type Natriuretic Peptide (CNP) in pathological tissue remodeling, for example in heart and liver fibrosis. CNP and its cyclic GMP producing guanylyl cyclase B (GC-B) receptor are expressed in the lungs, but it is unknown whether CNP can attenuate lung fibrosis by this pathway. To address this question, we performed studies in primary cultured lung fibroblasts. To examine the effects of the CNP/GC-B pathway on PDGF-BB-induced collagen production, proliferation, and migration in vitro, lung fibroblasts were cultured from wildtype control and GC-B knockout mice. Human lung fibroblasts from patients with IPF and healthy controls were obtained from the UGMLC Biobank. In RIA experiments, CNP, at 10nM and 100nM, markedly and similarly increased cGMP levels in both the murine and human lung fibroblasts, demonstrating GC-B/cGMP signaling. CNP reduced PDGF-BB induced proliferation and migration of lung fibroblasts in BrdU incorporation and gap closure assays, respectively. CNP strongly decreased PDGF-BB-induced collagen 1/3 expression as measured by immunocytochemistry and immunoblotting. Importantly, the protective actions of CNP were preserved in IPF fibroblasts. It is known that the profibrotic actions of PDGF-BB are partly mediated by phosphorylation and nuclear export of Forkhead Box O3 (FoxO3), a transcription factor downregulated in IPF. CNP prevented PDGF-BB elicited FoxO3 phosphorylation and nuclear exclusion in both murine and human control and IPF fibroblasts. CNP signaling and functions were abolished in GC-B-deficient lung fibroblasts. Taken together, the results show that CNP moderates the PDGF-BB-induced activation and differentiation of human and murine lung fibroblasts to myofibroblasts. This effect is mediated CNP-dependent by GC-B/cGMP signaling and FoxO3 regulation. To follow up the patho-physiological relevance of these results, we are generating mice with fibroblast-restricted GC-B deletion for studies in the model of bleomycin-induced pulmonary fibrosis.},
  subject      = {Idiopathische pulmonale Fibrose},
  language  = {en}
}
@phdthesis{Adam2024,
  author    = {Adam, Pia Sophie},
  title     = {Expression von PD-L1 und FGFR1-4 beim anaplastischen und gering differenzierten Schilddr{\"u}senkarzinom - Evaluation als pr{\"a}klinische diagnostische Marker},
  doi       = {10.25972/OPUS-35939},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359391},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Background: Treatment options for poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinoma are unsatisfactory and prognosis is generally poor. Lenvatinib (LEN), a multi-tyrosine kinase inhibitor targeting fibroblast growth factor receptors (FGFR) 1-4 is approved for advanced radioiodine refractory thyroid carcinoma, but response to single agent is poor in ATC. Recent reports of combining LEN with PD-1 inhibitor pembrolizumab (PEM) are promising. Materials and methods: Primary ATC (n=93) and PDTC (n=47) tissue samples diagnosed 1997-2019 at five German tertiary care centers were assessed for PD-L1 expression by immunohistochemistry using Tumor Proportion Score (TPS). FGFR 1-4 mRNA was quantified in 31 ATC and 14 PDTC with RNAscope in-situ hybridization. Normal thyroid tissue (NT) and papillary thyroid carcinoma (PTC) served as controls. Disease specific survival (DSS) was the primary outcome variable. Results: PD-L1 TPS≥50\% was observed in 42\% of ATC and 26\% of PDTC specimens. Mean PD-L1 expression was significantly higher in ATC (TPS 30\%) than in PDTC (5\%; p<0.01) and NT (0\%, p<0.001). 53\% of PDTC samples had PD-L1 expression ≤5\%. FGFR mRNA expression was generally low in all samples but combined FGFR1-4 expression was significantly higher in PDTC and ATC compared to NT (each p<0.001). No impact of PD-L1 and FGFR 1-4 expression was observed on DSS. Conclusion: High tumoral expression of PD-L1 in a large proportion of ATCs and a subgroup of PDTCs provides a rationale for immune checkpoint inhibition. FGFR expression is low thyroid tumor cells. The clinically observed synergism of PEM with LEN may be caused by immune modulation.},
  subject      = {Schilddr{\"u}senkrebs},
  language  = {de}
}
@phdthesis{Wilhelmi2024,
  author    = {Wilhelmi, Kai Alexander},
  title     = {Untersuchung von Ver{\"a}nderungen der myelinisierten Nervenfasern durch Entmarkung in Haut- und Nervenbiopsien von Patienten mit Polyneuropathie},
  doi       = {10.25972/OPUS-36004},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-360046},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {In dieser Arbeit wurde durch das immunhistochemische Anf{\"a}rben von nodalen (Natriumkan{\"a}le, NF), paranodalen (Caspr, NF) und internodalen (MBP) Proteinen der in Fingerhautbiopsien vorhanden Nervenfasern untersucht, ob eine Ver{\"a}nderung der typischen Verteilungsmuster dieser Proteine, eine demyelinisierende Polyneuropathie anzeigen kann. Dazu wurden am Universit{\"a}tsklinikum W{\"u}rzburg prospektiv 93 Polyneuropathie-Patienten und 25 Kontrollpersonen rekrutiert. Bei allen Patienten wurden Hautstanzbiospien am Zeigefinger durchgef{\"u}hrt. Bei 35 Patienten mit schweren oder unklaren Verl{\"a}ufen, wurden konsiliarisch Nervus suralis Biopsien durchgef{\"u}hrt. Aus einem Abschnitt von 27 dieser Biopsien, konnten im Rahmen dieser Arbeit Zupfnervenpr{\"a}parate angefertigt und analog zu den Hautbiopsien ausgewertet werden. Aus der Routinediagnostik der Klinik flossen weiterhin die Ergebnisse der elektrophysiologischen Routinediagnostik und der Histologiebefund der Nervus suralis Biopsien in die Auswertung ein. Zusammenfassend kamen ver{\"a}nderte Natriumkanalbanden in Fingerhautbiopsien signifikant h{\"a}ufiger bei Patienten mit elektrophysiologisch als demyelinisierend befundeten Polyneuropathien, als bei Patienten mit elektrophysiologisch als axonal befundeten Polyneuropathien vor. Vielfach fanden sich ver{\"a}nderte Natriumkanalbanden inmitten para- und internodal unauff{\"a}lliger Schn{\"u}rringe und umgekehrt. Diese Beobachtung st{\"u}tzt die bereits in Vorarbeiten vorgeschlagene und in der aktuellen Leitlinie zur Diagnostik f{\"u}r Polyneuropathien aufgegriffene Entit{\"a}t der Paranodopathien (Uncini, Susuki, \& Yuki, 2013). M{\"o}glich w{\"a}re, dass eine ver{\"a}nderte Verteilung der Natriumkan{\"a}le die schnelle Leitf{\"a}higkeit beeintr{\"a}chtigen und somit trotz intakter Bemarkung, elektrophysiologisch das Bild einer demyelinisierenden Neuropathie vermittelt. Ein direkter Zusammenhang zwischen dem Auftreten von doppelten und verl{\"a}ngerten Natriumkanalbanden und einzelnen Messwerten (z.B. Amplituden und Latenzzeiten) fand sich nicht. Auch in den Zupfnervenpr{\"a}paraten der Nervus suralis Biopsien, konnten o.g. Verteilungsmuster untersucht werden. Deren Vorkommen zeigte sich als unabh{\"a}ngig vom elektrophysiologischen und histologischen Befund, von der {\"A}tiologie der PNP und von den gefundenen Ver{\"a}nderungen in den Hautbiopsien des betreffenden Patienten.},
  subject      = {Polyneuropathie},
  language  = {de}
}
@phdthesis{StratmanngebHirster2024,
  author    = {Stratmann [geb. Hirster], Tizia},
  title     = {Ver{\"a}nderung der gesundheitsbezogenen Lebensqualit{\"a}t nach leberchirurgischen Operationen},
  doi       = {10.25972/OPUS-35997},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359977},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Es zeigte sich, dass die unmittelbare postoperative gesundheitsbezogene Lebensqualit{\"a}t erwartungsgem{\"a}ß deutlich eingeschr{\"a}nkt, jedoch nach circa sechs Monaten wieder auf dem Ausgangsniveau der pr{\"a}operativen Ebene angekommen war. Sowohl die Symptomskalen als auch die Funktionsskalen zeigten statistisch signifikante Unterschiede der erhobenen Werte bez{\"u}glich des Vergleichs der pr{\"a}operativen zu den postoperativen Daten, dasselbe ließ sich {\"u}ber die Werte im Rahmen der Verlaufskontrolle nach circa sechs Monaten erheben. Eine kurzfristige Einbuße der Lebensqualit{\"a}t durch einen station{\"a}ren Krankenhausaufenthalt sowie einer operativen Versorgung erscheint logisch. F{\"u}r die zuk{\"u}nftige Entscheidung vor allem auch f{\"u}r Personen, welche aufgrund einer benignen Leberraumforderung eine operative Versorgung erhalten sollen, ist zu sagen, dass die globale gesundheitsbezogene Lebensqualit{\"a}t postoperativ nach circa sechs Monaten gleich bzw. etwas gebessert ausfiel und somit eine Rechtfertigung der operativen Versorgung auch bei benignen Erkrankungen darstellen kann. Ein wesentlicher Aspekt der Arbeit ist, dass gezeigt werden konnte, dass auch bei komplexen Lebereingriffen eine schnelle Rekonvaleszenz - mindestens auf das Niveau vor dem Eingriff - innerhalb der ersten sechs Monate zu erwarten ist. Die systematische Erfassung der Lebensqualit{\"a}t hilft die postoperativen Einschr{\"a}nkungen und die Rekonvaleszenz zu normieren.},
  subject      = {Leberresektion},
  language  = {de}
}
@phdthesis{Menger2024,
  author    = {Menger, Kristina Rebekka},
  title     = {Bauchlagerung f{\"u}r nicht-intubierte ARDS- und COVID-19 Patient/innen: eine systematische {\"U}bersichtsarbeit},
  doi       = {10.25972/OPUS-35986},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359865},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Die Bauchlagerung von intubierten ARDS-Patient/innen mit einer schlechten Oxygenierung wird laut Leitlinie seit mehreren Jahren als supportive Therapiemaßnahme empfohlen. Im Rahmen der COVID-19 Pandemie wurde nun erstmalig die Bauchlagerung auch bei hypox{\"a}mischen, nicht-intubierten Patient/innen untersucht. Diese Fragestellung wurde in der vorliegenden Arbeit mittels einer systematischen {\"U}bersichtsarbeit betrachtet. Aufgrund der aktuellen Pandemiesituation wurden neben ARDS-Patient/innen im Allgemeinen insbesondere COVID-19 Patient/innen mit einem akuten Lungenversagen als Subgruppe untersucht. Am 21.11.2020 wurde eine systematische Suche nach Studien in den Datenbanken MEDLINE, Cochrane COVID-19 Study Register und Living Overview of the Evidence platform durchgef{\"u}hrt. Die Ergebnisse wurden, wo m{\"o}glich, in Form einer Meta-Analyse zusammengefasst, in Tabellen darstellt oder deskriptiv beschrieben. Das Risiko f{\"u}r Bias wurde jeweils f{\"u}r die eingeschlossenen kontrollierten Studien mittels ROBINS-I beurteilt. Die Vertrauensw{\"u}rdigkeit der Evidenz der gesamten Arbeit wurde mit Hilfe des GRADE-Ansatzes untersucht. Insgesamt wurden 30 Studien eingeschlossen, davon 4 kontrollierte Studien, keine RCTs. In 3 der kontrollierten Studien wurde die Bauchlagerung bei COVID-19 Patient/innen untersucht, in einer bei Patient/innen mit einem anderweitig verursachten ARDS. Es ist unklar, ob die Bauchlagerung die Intubationsrate (RR = 0,92; 95\% KI: 0,59 - 1,44; I² = 65\%; sehr niedrige Vertrauensw{\"u}rdigkeit der Evidenz), die Mortalit{\"a}t (RR = 0,55; 95\% KI: 0,23 - 1,30; I² = 60\%; sehr niedrige Vertrauensw{\"u}rdigkeit der Evidenz) und die Wahrscheinlichkeit f{\"u}r eine Aufnahme auf die Intensivstation (RR = 0,94; 95\% KI: 0,54 - 1,63; I2 = 71\%; sehr niedrige Vertrauensw{\"u}rdigkeit der Evidenz) verringern kann. Auch f{\"u}r die anderen betrachteten Endpunkte konnte kein signifikanter Effekt der Bauchlagerung nachgewiesen werden Im Vergleich der Subgruppen „Nicht-COVID-19" (8 Studien) und „COVID-19" (22 Studien) konnten in Bezug auf alle betrachteten Endpunkte keine relevanten Unterschiede festgestellt werden. Insgesamt ist die Evidenz nicht ausreichend, um Vor- und Nachteile der Bauchlagerung f{\"u}r nicht-intubierte ARDS Patient/innen gegen{\"u}ber der {\"u}blichen R{\"u}ckenlagerung aufzuzeigen und diese f{\"u}r die Praxis zu empfehlen.},
  subject      = {Bauchlage},
  language  = {de}
}
@phdthesis{Chen2024,
  author    = {Chen, Xinyu},
  title     = {How natural walking changes occipital alpha oscillations and concurrently modulates cognitive processes},
  doi       = {10.25972/OPUS-35295},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-352958},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Humans actively interact with the world through a wide range of body movements. To understand human cognition in its natural state, we need to incorporate ecologically relevant body movement into our account. One fundamental body movement during daily life is natural walking. Despite its ubiquity, the impact of natural walking on brain activity and cognition has remained a realm underexplored. In electrophysiology, previous studies have shown a robust reduction of ongoing alpha power in the parieto-occipital cortex during body movements. However, what causes the reduction of ongoing alpha, namely whether this is due to body movement or prevalent sensory input changes, was unknown. To clarify this, study 1 was performed to test if the alpha reduction is dependent on visual input. I compared the resting state alpha power during natural walking and standing, in both light and darkness. The results showed that natural walking led to decreased alpha activity over the occipital cortex compared to standing, regardless of the lighting condition. This suggests that the movement-induced modulation of occipital alpha activity is not driven by visual input changes during walking. I argue that the observed alpha power reduction reflects a change in the state of the subject based on disinhibition induced by walking. Accordingly, natural walking might enhance visual processing and other cognitive processes that involve occipital cortical activity. I first tested this hypothesis in vision. Study 2 was performed to examine the possible effects of natural walking across visual processing stages by assessing various neural markers during different movement states. The findings revealed an amplified early visual response, while a later visual response remain unaffected. A follow-up study 3 replicated the walking-induced enhancement of the early visual evoked potential and showed that the enhancement was dependent on specific stimulus-related parameters (eccentricity, laterality, distractor presence). Importantly, the results provided evidence that the enhanced early visual responses are indeed linked to the modulation of ongoing occipital alpha power. Walking also modulated the stimulus-induced alpha power. Specifically, it showed that when the target appeared in the fovea area without a distractor, walking exhibited a significantly reduced modulation of alpha power, and showed the largest difference to standing condition. This effect of eccentricity indicates that during later visual processing stages, the visual input in the fovea area is less processed than in peripheral areas while walking. The two visual studies showed that walking leads to an enhancement in temporally early visual processes which can be predicted by the walking-induced change in ongoing alpha oscillation likely marking disinhibition. However, while walking affects neural markers of early sensory processes, it does not necessarily lead to a change in the behavioural outcome of a sensory task. The two visual studies suggested that the behavioural outcome seems to be mainly based on later processing stages. To test the effects of walking outside the visual domain, I turned to audition in study 4. I investigated the influence of walking in a particular path vs. simply stepping on auditory processing. Specifically, the study tested whether enhanced processing due to natural walking can be found in primary auditory brain activity and whether the processing preferences are dependent on the walking path. In addition, I tested whether the changed spatial processing that was reported in previous visual studies can be seen in the auditory domain. The results showed enhanced sensory processing due to walking in the auditory domain, which was again linked to the modulation of occipital alpha oscillation. The auditory processing was further dependent on the walking path. Additionally, enhanced peripheral sensory processing, as found in vision, was also present in audition. The findings outside vision supported the idea of natural walking affecting cognition in a rather general way. Therefore in my study 5, I examined the effect of natural walking on higher cognitive processing, namely divergent thinking, and its correlation with the modulation of ongoing alpha oscillation. I analyzed alpha oscillations and behavioural performance during restricted and unrestricted movement conditions while subjects completed a Guilford's alternate uses test. The results showed that natural walking, as well as missing body restriction, reduces the occipital alpha ongoing power independent of the task phase which goes along with higher test scores. The occipital alpha power reduction can therefore be an indicator of a changed state that allows improved higher cognitive processes. In summary, the research presented in this thesis highlights that natural walking can change different processes in the visual and auditory domain as well as higher cognitive processes. The effect can be attributed to the movement of natural walking itself rather than to changes in sensory input during walking. The results further indicate that the walking-induced modulation of ongoing occipital alpha oscillations drives the cognitive effects. We therefore suggest that walking changes the inhibitory state which can influence awareness and attention. Such a mechanism could facilitate an adaptive enhancement in cognitive processes and thereby optimize movement-related behaviour such as navigation.},
  subject      = {Walking},
  language  = {en}
}
@phdthesis{Karwen2024,
  author    = {Karwen, Till},
  title     = {Platelets promote insulin secretion of pancreatic β-cells},
  doi       = {10.25972/OPUS-31393},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313933},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {The pancreas is the key organ for the maintenance of euglycemia. This is regulated in particular by α-cell-derived glucagon and β-cell-derived insulin, which are released in response to nutrient deficiency and elevated glucose levels, respectively. Although glucose is the main regulator of insulin secretion, it is significantly enhanced by various potentiators. Platelets are anucleate cell fragments in the bloodstream that are essential for hemostasis to prevent and stop bleeding events. Besides their classical role, platelets were implemented to be crucial for other physiological and pathophysiological processes, such as cancer progression, immune defense, and angiogenesis. Platelets from diabetic patients often present increased reactivity and basal activation. Interestingly, platelets store and release several substances that have been reported to potentiate insulin secretion by β-cells. For these reasons, the impact of platelets on β-cell functioning was investigated in this thesis. Here it was shown that both glucose and a β-cell-derived substance/s promote platelet activation and binding to collagen. Additionally, platelet adhesion specifically to the microvasculature of pancreatic islets was revealed, supporting the hypothesis of their influence on glucose homeostasis. Genetic or pharmacological ablation of platelet functioning and platelet depletion consistently resulted in reduced insulin secretion and associated glucose intolerance. Further, the platelet-derived lipid fraction was found to enhance glucose-stimulated insulin secretion, with 20-hydroxyeicosatetraenoic acid (20-HETE) and possibly also lyso-precursor of platelet-activating factor (lysoPAF) being identified as crucial factors. However, the acute platelet-stimulated insulin secretion was found to decline with age, as did the levels of platelet-derived 20-HETE. In addition to their direct stimulatory effect on insulin secretion, specific defects in platelet activation have also been shown to affect glucose homeostasis by potentially influencing islet vascular development. Taking together, the results of this thesis suggest a direct and indirect mechanism of platelets in the regulation of insulin secretion that ensures glucose homeostasis, especially in young individuals.},
  subject      = {Thrombozyt},
  language  = {en}
}