@article{WrońskiWyborskiMusiałetal.2021, author = {Wroński, Piotr Andrzej and Wyborski, Paweł and Musiał, Anna and Podemski, Paweł and Sęk, Grzegorz and H{\"o}fling, Sven and Jabeen, Fauzia}, title = {Metamorphic Buffer Layer Platform for 1550 nm Single-Photon Sources Grown by MBE on (100) GaAs Substrate}, series = {Materials}, volume = {14}, journal = {Materials}, number = {18}, issn = {1996-1944}, doi = {10.3390/ma14185221}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246145}, year = {2021}, abstract = {We demonstrate single-photon emission with a low probability of multiphoton events of 5\% in the C-band of telecommunication spectral range of standard silica fibers from molecular beam epitaxy grown (100)-GaAs-based structure with InAs quantum dots (QDs) on a metamorphic buffer layer. For this purpose, we propose and implement graded In content digitally alloyed InGaAs metamorphic buffer layer with maximal In content of 42\% and GaAs/AlAs distributed Bragg reflector underneath to enhance the extraction efficiency of QD emission. The fundamental limit of the emission rate for the investigated structures is 0.5 GHz based on an emission lifetime of 1.95 ns determined from time-resolved photoluminescence. We prove the relevance of a proposed technology platform for the realization of non-classical light sources in the context of fiber-based quantum communication applications.}, language = {en} } @misc{Wu2021, type = {Master Thesis}, author = {Wu, Dong}, title = {Aspects of Gender in The Unofficial History of the Scholars}, doi = {10.25972/OPUS-21920}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219202}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {The present study focuses on Rulin waishi 儒林外史 (The Unofficial History of the Scholars), a well-known Qing novel, from the perspective of gender. It attempts to contribute to the discussion about Chinese masculinity by identifying the representation of the scholars' masculinity in Rulin waishi and offer a better understanding of the novel's position regarding femininity and women. This project shows that the novel nevertheless reflects rather than challenges gender ideologies of its time. The ideal manhood showed in the novel comprises real virtues and authentic learning. It goes against the traditional, orthodox Confucian masculinity which advocates that officialdom is the glorious path to fulfill a learned man's masculinity. It is mainly due to Wu Jingzi's own failure in the civil service examinations and official careers. Regarding the relation of masculinity and sexuality, the novel reveals that a masculine man is not tempted by female charm but can enjoy a harmonious and companionate marriage. Besides, scholars show great anxiety about their masculinity since they are in a marginal position in society. Their manliness is challenged by officials, merchants, and even commoners, as well as their colleagues. Through a careful examination of stories of Pinniang, Miss Lu, and Mrs. Wang, it reveals that the novel holds a conventional opinion on women although it criticizes widow suicide and shows an egalitarian husband-wife relationship. It praises Confucian womanly virtues, such as following and serving the husband, managing the household, and keeping chastity. Female sexuality is blamed as an evil temptation to lead men to go astray. Women's learning gains legitimacy when serving to fulfill domestic responsibilities. It carries the Confucian message that men should take the lead and maintain order in the household and reinforces the rightful patriarchy. In a word, rather than go ahead of its time, Rulin waishi holds a conservative attitude towards gender issues.}, language = {en} } @phdthesis{Wu2019, author = {Wu, Fang}, title = {Adding new functions to insulin-like growth factor-I (IGF-I) via genetic codon expansion}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175330}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Insulin-like growth factor-I (IGF-I) is a 70-amino acid polypeptide with a molecular weight of approximately 7.6 kDa acting as an anabolic effector. It is essential for tissue growth and remodeling. Clinically, it is used for the treatment of growth disorders and has been proposed for various other applications including musculoskeletal diseases. Unlike insulin, IGF-I is complexed to at least six high-affinity binding proteins (IGFBPs) exerting homeostatic effects by modulating IGF-I availability to its receptor (IGF-IR) on most cells in the body as well as changing the distribution of the growth factor within the organism.1-3 Short half-lived IGF-I have been the driving forces for the design of localized IGF-I depot systems or protein modification with enhanced pharmacokinetic properties. In this thesis, we endeavor to present a versatile biologic into which galenical properties were engineered through chemical synthesis, e.g., by site-specific coupling of biomaterials or complex composites to IGF-I. For that, we redesigned the therapeutic via genetic codon expansion resulting in an alkyne introduced IGF-I, thereby becoming a substrate for biorthogonal click chemistries yielding a site-specific decoration. In this approach, an orthogonal pyrrolysine tRNA synthetase (PylRS)/tRNAPyl CUA pair was employed to direct the co-translational incorporation of an unnatural amino acid—¬propargyl-L-lysine (plk)—bearing a clickable alkyne functional handle into IGF-I in response to the amber stop codon (UAG) introduced into the defined position in the gene of interest. We summarized the systematic optimization of upstream and downstream process alike with the ultimate goal to increase the yield of plk modified IGF-I therapeutic, from the construction of gene fusions resulting in (i) Trx-plk-IGF-I fusion variants, (ii) naturally occurring pro-IGF-I protein (IGF-I + Ea peptide) (plk-IGF-I Ea), over the subsequent bacterial cultivation and protein extraction to the final chromatographic purification. The opportunities and hurdles of all of the above strategies were discussed. Evidence was provided that the wild-type IGF-I yields were pure by exploiting the advantages of the pHisTrx expression vector system in concert with a thrombin enzyme with its highly specific proteolytic digestion site and multiple-chromatography steps. The alkyne functionality was successfully introduced into IGF-I by amber codon suppression. The proper folding of plk-IGF-I Ea was assessed by WST-1 proliferation assay and the detection of phosphorylated AKT in MG-63 cell lysate. The purity of plk-IGF-I Ea was monitored with RP-HPLC and SDS-PAGE analysis. This work also showed site-specific coupling an alkyne in plk-IGF-I Ea by copper (I)-catalyzed azide-alkyne cycloaddition (CuAAC) with potent activities in vitro. The site-specific immobilization of plk-IGF-I Ea to the model carrier (i.e., agarose beads) resulted in enhanced cell proliferation and adhesion surrounding the IGF-I-presenting particles. Cell proliferation and differentiation were enhanced in the accessibility of IGF-I decorated beads, reflecting the multivalence on cellular performance. Next, we aimed at effectively showing the disease environment by co-delivery of fibroblast growth factor 2 (FGF2) and IGF-I, deploying localized matrix metalloproteinases (MMPs) upregulation as a surrogate marker driving the response of the drug delivery system. For this purpose, we genetically engineered FGF2 variant containing an (S)-2-amino-6-(((2-azidoethoxy)carbonyl)amino)hexanoic acid incorporated at its N-terminus, followed by an MMPs-cleavable linker (PCL) and FGF2 sequence, thereby allowing site-directed, specific decoration of the resultant azide-PCL-FGF2 with the previously mentioned plk-IGF-I Ea to generate defined protein-protein conjugates with a PCL in between. The click reaction between plk-IGF-I Ea and azide-PCL-FGF2 was systematically optimized to increase the yield of IGF-FGF conjugates, including reaction temperature, incubation duration, the addition of anionic detergent, and different ratios of the participating biopharmaceutics. The challenge here was that CuAAC reaction components or conditions might oxidize free cysteines of azide-PCL-FGF2 and future work needs to present the extent of activity retention after conjugation. Furthermore, our study provides potential options for dual-labeling of IGF-I either by the introduction of unnatural amino acids within two distinct positions of the protein of interest for parallel "double-click" labeling of the resultant plk-IGF-I Ea-plk or by using a combination of enzymatic-catalyzed and CuAAC bioorthogonal coupling strategies for sequentially dual-labeling of plk-IGF-I Ea. In conclusion, genetic code expansion in combination with click-chemistry provides the fundament for novel IGF-I analogs allowing unprecedented site specificity for decoration. Considerable progress towards IGF-I based therapies with enhanced pharmacological properties was made by demonstrating the feasibility of the expression of plk incorporated IGF-I using E. coli and retained activity of unconjugated and conjugated IGF-I variant. Dual-labeling of IGF-I provides further insights into the functional requirements of IGF-I. Still, further investigation warrants to develop precise IGF-I therapy through unmatched temporal and spatial regulation of the pleiotropic IGF-I.}, subject = {Insulin-like Growth Factor I}, language = {en} } @article{WuReimannSiddiquietal.2019, author = {Wu, Hao and Reimann, Sabine and Siddiqui, Sophiya and Haag, Rainer and Siegmund, Britta and Dernedde, Jens and Glauben, Rainer}, title = {dPGS Regulates the Phenotype of Macrophages via Metabolic Switching}, series = {Macromolecular Bioscience}, volume = {19}, journal = {Macromolecular Bioscience}, number = {12}, doi = {10.1002/mabi.201900184}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212711}, year = {2019}, abstract = {The synthetic compound dendritic polyglycerol sulfate (dPGS) is a pleiotropic acting molecule but shows a high binding affinity to immunological active molecules as L-/P-selectin or complement proteins leading to well described anti-inflammatory properties in various mouse models. In order to make a comprehensive evaluation of the direct effect on the innate immune system, macrophage polarization is analyzed in the presence of dPGS on a phenotypic but also metabolic level. dPGS administered macrophages show a significant increase of MCP1 production paralleled by a reduction of IL-10 secretion. Metabolic analysis reveals that dPGS could potently enhance the glycolysis and mitochondrial respiration in M0 macrophages as well as decrease the mitochondrial respiration of M2 macrophages. In summary the data indicate that dPGS polarizes macrophages into a pro-inflammatory phenotype in a metabolic pathway-dependent manner.}, language = {en} } @article{WuZhaoHochreinetal.2023, author = {Wu, Hao and Zhao, Xiufeng and Hochrein, Sophia M. and Eckstein, Miriam and Gubert, Gabriela F. and Kn{\"o}pper, Konrad and Mansilla, Ana Maria and {\"O}ner, Arman and Doucet-Ladev{\`e}ze, Remi and Schmitz, Werner and Ghesqui{\`e}re, Bart and Theurich, Sebastian and Dudek, Jan and Gasteiger, Georg and Zernecke, Alma and Kobold, Sebastian and Kastenm{\"u}ller, Wolfgang and Vaeth, Martin}, title = {Mitochondrial dysfunction promotes the transition of precursor to terminally exhausted T cells through HIF-1α-mediated glycolytic reprogramming}, series = {Nature Communications}, volume = {14}, journal = {Nature Communications}, doi = {10.1038/s41467-023-42634-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-358052}, year = {2023}, abstract = {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.}, language = {en} } @phdthesis{Wu2013, author = {Wu, Lingdan}, title = {Emotion Regulation in Addicted Smokers}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85471}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Background: Nicotine addiction is the most prevalent type of drug addiction that has been described as a cycle of spiraling dysregulation of the brain reward systems. Imaging studies have shown that nicotine addiction is associated with abnormal function in prefrontal brain regions that are important for cognitive emotion regulation. It was assumed that addicts may perform less well than healthy nonsmokers in cognitive emotion regulation tasks. The primary aims of this thesis were to investigate emotional responses to natural rewards among smokers and nonsmokers and to determine whether smokers differ from nonsmokers in cognitive regulation of positive and negative emotions. To address these aims, two forms of appraisal paradigms (i.e., appraisal frame and reappraisal) were applied to compare changes in emotional responses of smokers with that of nonsmokers as a function of appraisal strategies. Experiment 1: The aim of the first experiment was to evaluate whether and how appraisal frames preceding positive and negative picture stimuli affect emotional experience and facial expression of individuals. Twenty participants were exposed to 125 pairs of auditory appraisal frames (either neutral or emotional) followed by picture stimuli reflecting five conditions: unpleasant-negative, unpleasant-neutral, pleasant-positive, pleasant-neutral and neutral-neutral. Ratings of valence and arousal as well as facial EMG activity over the corrugator supercilii and the zygomaticus major were measured simultaneously. The results indicated that appraisal frames could alter both subjective emotional experience and facial expressions, irrespective of the valence of the pictorial stimuli. These results suggest and support that appraisal frame is an efficient paradigm in regulation of multi-level emotional responses. 8 Experiment 2: The second experiment applied the appraisal frame paradigm to investigate how smokers differ from nonsmokers on cognitive emotion regulation. Sixty participants (22 nonsmokers, 19 nondeprived smokers and 19 12-h deprived smokers) completed emotion regulation tasks as described in Experiment 1 while emotional responses were concurrently recorded as reflected by self-ratings and psychophysiological measures (i.e., facial EMG and EEG). The results indicated that there was no group difference on emotional responses to natural rewards. Moreover, nondeprived smokers and deprived smokers performed as well as nonsmokers on the emotion regulation task. The lack of group differences in multiple emotional responses (i.e., self-reports, facial EMG activity and brain EEG activity) suggests that nicotine addicts have no deficit in cognitive emotion regulation of natural rewards via appraisal frames. Experiment 3: The third experiment aimed to further evaluate smokers' emotion regulation ability by comparing performances of smokers and nonsmokers in a more challenging cognitive task (i.e., reappraisal task). Sixty-five participants (23 nonsmokers, 22 nondeprived smokers and 20 12-h deprived smokers) were instructed to regulate emotions by imagining that the depicted negative or positive scenario would become less negative or less positive over time, respectively. The results showed that nondeprived smokers and deprived smokers responded similarly to emotional pictures and performed as well as nonsmokers in down-regulating positive and negative emotions via the reappraisal strategy. These results indicated that nicotine addicts do not have deficit in emotion regulation using cognitive appraisal strategies. In sum, the three studies consistently revealed that addicted smokers were capable to regulate emotions via appraisal strategies. This thesis establishes the groundwork for therapeutic use of appraisal instructions to cope with potential self-regulation failures in nicotine addicts.}, subject = {Gef{\"u}hl}, language = {en} } @article{WuPuAllenetal.2012, author = {Wu, Lingdan and Pu, Jie and Allen, John J. B. and Pauli, Paul}, title = {Recognition of facial expressions in individuals with elevated levels of depressive symptoms: an eye-movement study}, series = {Depression Research and Treatment}, volume = {2012}, journal = {Depression Research and Treatment}, number = {249030}, doi = {10.1155/2012/249030}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-123153}, year = {2012}, abstract = {Previous studies consistently reported abnormal recognition of facial expressions in depression. However, it is still not clear whether this abnormality is due to an enhanced or impaired ability to recognize facial expressions, and what underlying cognitive systems are involved. The present study aimed to examine how individuals with elevated levels of depressive symptoms differ from controls on facial expression recognition and to assess attention and information processing using eye tracking. Forty participants (18 with elevated depressive symptoms) were instructed to label facial expressions depicting one of seven emotions. Results showed that the high-depression group, in comparison with the low-depression group, recognized facial expressions faster and with comparable accuracy. Furthermore, the high-depression group demonstrated greater leftwards attention bias which has been argued to be an indicator of hyperactivation of right hemisphere during facial expression recognition.}, language = {en} } @article{WuWinklerWieseretal.2015, author = {Wu, Lingdan and Winkler, Markus H. and Wieser, Matthias J. and Andreatta, Marta and Li, Yonghui and Pauli, Paul}, title = {Emotion regulation in heavy smokers: experiential, expressive and physiological consequences of cognitive reappraisal}, series = {Frontiers in Psychology}, volume = {6}, journal = {Frontiers in Psychology}, number = {1555}, doi = {10.3389/fpsyg.2015.01555}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145225}, year = {2015}, abstract = {Emotion regulation dysfunctions are assumed to contribute to the development of tobacco addiction and relapses among smokers attempting to quit. To further examine this hypothesis, the present study compared heavy smokers with non-smokers (NS) in a reappraisal task. Specifically, we investigated whether non-deprived smokers (NDS) and deprived smokers (DS) differ from non-smokers in cognitive emotion regulation and whether there is an association between the outcome of emotion regulation and the cigarette craving. Sixty-five participants (23 non-smokers, 22 NDS, and 20 DS) were instructed to down-regulate emotions by reappraising negative or positive pictorial scenarios. Self-ratings of valence, arousal, and cigarette craving as well as facial electromyography and electroencephalograph activities were measured. Ratings, facial electromyography, and electroencephalograph data indicated that both NDS and DS performed comparably to nonsmokers in regulating emotional responses via reappraisal, irrespective of the valence of pictorial stimuli. Interestingly, changes in cigarette craving were positively associated with regulation of emotional arousal irrespective of emotional valence. These results suggest that heavy smokers are capable to regulate emotion via deliberate reappraisal and smokers' cigarette craving is associated with emotional arousal rather than emotional valence. This study provides preliminary support for the therapeutic use of reappraisal to replace maladaptive emotion-regulation strategies in nicotine addicts.}, language = {en} } @phdthesis{Wu2006, author = {Wu, Rongxue}, title = {Integrins and SPARC : potential implications for cardiac remodeling}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-17531}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Der enorme Umbau des Herzgewebes, wie man ihn nach Druck{\"u}berlastung des Ventrikels oder MyokardInfarkt beobachten kann, gilt als eine der kausalen Ursachen des Herzversagens. Die Ver{\"a}nderungen in der Architektur des Herzens beeinflussen die mechanischen Eigenschaften des Herzmuskels, begr{\"u}ndet sind sie jedoch in Anpassungsprozessen auf der zellul{\"a}ren Ebene vor allem in einer Modulation der Expression bestimmter Gene. Gemeinsam mit Integrinen, den Transmembran-Rezeptoren, welche die extrazellul{\"a}re Umgebung mit dem intrazellul{\"a}ren Zytoskelett verbinden, geh{\"o}ren Proteine der extrazellul{\"a}ren Matrix (ECM) und matrizellul{\"a}re Proteine zu den Schl{\"u}sselkomponenten, die den Umbauprozess im Herzen steuern. Aus diesen Gr{\"u}nden hatte diese Doktorarbeit zum Ziel, die Rolle der Integrine f{\"u}r die Regulation der Genexpression und die Leistungsf{\"a}higkeit des Herzmuskels w{\"a}hrend der durch Druck{\"u}berlastung oder myokardialen Infarkt (MI) hervorgerufenen Wundheilungsprozesse zu analysieren. Um die Beteiligung von Integrin Beta 1 zu untersuchen, wurde ein experimentelles Modell der Druck{\"u}berlastung im Mausherzen (aortic banding; Konstriktion der Aorta; AB) eingesetzt, wobei M{\"a}use mit einer konditionalen, Herz-spezifischen Deletion des Integrin Beta 1 Gens untersucht wurden. Ein besonderes Augenmerk wurde dabei auf die physiologischen Unterschiede und eine ver{\"a}nderte Genexpression im gestressten Herzen in An- oder Abwesenheit von Integrin Beta 1 gelegt. Interessanterweise wurden die M{\"a}use, welche eine Kombination aus Integrin knock-out Allel und dem Kardiomyozyten-spezifischen konditionalen knock-out Allel von Integrin Beta 1 aufwiesen im normalen Mendelschen Verh{\"a}ltnis geboren und wuchsen normal auf. Obwohl diese Tiere immer noch geringe Mengen von Integrin Beta 1 in ihrem Herzen aufwiesen (exprimiert von nicht-Myozyten), besaßen diese M{\"a}use eine ver{\"a}nderte Herzfunktion und waren sehr sensitiv gegen{\"u}ber AB. Im Gegensatz zu der kompensatorischen hypertrophischen Reaktion, die in Wildtyp M{\"a}usen zu beobachten war, zeigte sich in den Integrin Beta 1-defizienten Mausherzen kein Gewebeumbau. Auch die erh{\"o}hte Expression von verschiedenen ECM Proteinen, insbesondere die verst{\"a}rkte Expression des matrizellul{\"a}ren Proteins SPARC, unterblieb nach AB in den Integrin Beta 1-defizienten Tieren. Interessanterweise konnte auch eine transiente Erh{\"o}hung der SPARC mRNA w{\"a}hrend der Umbauprozesse im Herzen in Folge von myokardialem Infarkt (MI) mittels cDNA Makroarrays festgestellt werden. In der Tat fanden sich gr{\"o}ßere Mengen von SPARC bereits 2 Tage (~2,5-fach erh{\"o}ht), 7 Tage (~4-fach erh{\"o}ht) und 1 Monat (~2-fach erh{\"o}ht) nach MI, w{\"a}hrend ein spezifischer Inhibitor der Integrin alpha v Untereinheit diese Hochregulation von SPARC in vivo verhinderte. Immunfluoreszenz Untersuchungen von Herzgewebe verdeutlichten, dass sich die erh{\"o}hte Expression von SPARC auf das Infarktareal beschr{\"a}nkte, dass die Expression von SPARC nach einer anf{\"a}nglichen Erh{\"o}hung im Verlauf von 1 Monaten wieder auf das Anfangsniveau zur{\"u}ckging und dass die verst{\"a}rkte Expression von der Einwanderung von Fibroblasten in das isch{\"a}mische Herzgewebe begleitet war. In vitro stimulierten die Wachstumsfaktoren TGF-Beta 1 und PDGF-BB die Expression von SPARC durch Fibroblasten. Wie sich an Hand von ELISA und Western Blot Untersuchungen feststellen ließ, war die Inhibition von Integrin Beta v nicht in der Lage, die durch TGF-Beta 1 oder PDGF induzierte Sekretion von SPARC zu beeinflussen. Jedoch zeigte sich, dass Vitronektin, ein Ligand von Integrin alpha v, sowohl die Sekretion von TGF-Beta 1 als auch von PDGF-BB durch Kardiomyozyten induzierte und diese Reaktion wurde durch den Integrin alpha v Inhibitor komplett unterdr{\"u}ckt. In funktioneller Hinsicht wirkte SPARC auf die durch ECM Proteine induzierte Migration von Fibroblasten ein, so dass man davon ausgehen kann, dass die lokale Freisetzung von SPARC nach myokardialem Infarkt zur Wundheilung im Herzen beitr{\"a}gt. Zusammenfassend l{\"a}ßt die Kombination der in vivo und in vitro erhobenen experimentellen Daten den Schluss zu, dass mehrere Integrin Untereinheiten eine entscheidende Rolle w{\"a}hrend der Gewebeumbildung im Herzen spielen. Integrin-abh{\"a}ngige Genexpressionsereignisse wie beispielsweise die erh{\"o}hte Expression von SPARC nach MI sind entscheidend an der Koordination der Wundheilung beteiligt. Diese Prozesse scheinen auf einer komplexen Wechselwirkung und Kommunikation zwischen verschiedenen Zelltypen wie Kardiomyozyten und Fibroblasten zu beruhen, um lokal begrenzt eine Heilung und Vernarbung des verletzten Gewebes zu regulieren. Die Aufkl{\"a}rung des fein abgestimmten Wechselspiels zwischen Integrinen matrizellul{\"a}ren Proteinen wie SPARC und Wachstumsfaktoren wird sicherlich zu einem besseren und klinisch nutzbarem Verst{\"a}ndnis der molekularen Mechanismen des Gewebeumbaus im Herzen beitragen.}, subject = {Integrine}, language = {en} } @phdthesis{Wu2007, author = {Wu, Rongxue}, title = {Treatment with integrin alpha v inhibitor abolishes compensatory cardiac hypertrophy due to altered signal transduction and ECM gene expression}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-21339}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {Integrine sind Transmembranrezeptoren, welche mechanische Signale von der extrazellul{\"a}ren Matrix (ECM) zum Zytoskelett {\"u}bermitteln ("outside-in-signaling"). Viele molekulare Defekte in der Verbindung zwischen Zytoskelett und ECM erzeugen bekanntermaßen Kardiomyopathien. alpha v Integrin scheint eine Hauptrolle in verschiedenen Prozessen der kardialen Reorganisation zu spielen, wie z.B. Regulation der Zellproliferation, -migration und -differenzierung. Unsere Hypothese war, dass alpha v -Integrin-vermittelte Signale notwendig f{\"u}r die kompensatorische Hypertrophie nach Aortenkonstriktion sind und assoziiert mit der Modulation der Expression von ECM-Proteinen. Dazu wurden M{\"a}use mit einem spezifischen alpha v Integrin-Inhibitor behandelt und einer Aortenkonstriktion (AB) unterzogen. Nach zwei Tagen und nach sieben Tagen wurden die M{\"a}use echokardiographisch untersucht und eingehende h{\"a}modynamische Untersuchungen wurden durchgef{\"u}hrt. Die Behandlung mit dem alpha v -Integrin-Inhibitor f{\"u}hrte zu einer dilatativen Kardiomyopathie und Herzinsuffizienz in den AB-M{\"a}usen, gekennzeichnet durch einen dilatierten linken Ventrikel, schlechte linksventrikul{\"a}re Funktion und einer Lungenstauung, wohingegen die scheinbehandelten Tiere eine kompensatorische Hypertrophie des linken Ventrikels zeigten. Untersuchungen der beteiligten Signalwege zeigten eine Aktivierung des p38 MAP-Kinase-Signalwegs, von ERK 1 und -2, der Focal Adhesion Kinase FAK und Tyrosin-Phosphorylierung von c-Src in den Kontrollherzen, was in den Inhibitor-behandelten Herzen fehlte. mRNA-Expressionsanalysen f{\"u}r 96 Gene mittels "Micro-Arrays" ermittelten verschiedene genomische Ziele des alpha v -Integrin-aktivierten Signalwegs. 18 f{\"u}r ECM-Proteine codierende Gene wurden mehr als 2-fach hochreguliert, z.B. Kollagen (8,11-fach ± 2,2), Fibronectin (2,32 ± 094), SPARC (3,78 ± 0,12), ADAMTS-1 (3,51 ± 0,81) und TIMP2 (2,23 ± 0,98), wohingegen die Aktivierung dieser Gene in Inhibitor-behandelten Tieren aufgehoben war. Wir folgern daraus, dass Signalwege unterhalb von alpha v -Integrin, mediiert durch MAP-Kinasen, FAK und c-Src, zu einer verst{\"a}rkten Expression von ECM-Komponenten f{\"u}hrt, welche f{\"u}r die kompensatorische Antwort auf Druckbelastung n{\"o}tig sind.}, subject = {Antigen}, language = {en} } @article{WuBeckerWaagetal.1992, author = {Wu, Y. S. and Becker, Charles R. and Waag, A. and Bicknell-Tassius, R. N. and Landwehr, G.}, title = {Thermal effects on (100) CdZnTe substrates as studied by x-ray photoelectron spectroscopy and reflection high energy electron diffraction}, issn = {0003-6951}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37801}, year = {1992}, abstract = {The influence of different CdZnTe substrate treatments prior to II-VI molecular beam epitaxial growth on surface stoichiometry, oxygen, and carbon contamination has been studied using x-ray photoelectron spectroscopy and reflection high energy electron diffraction. Heating the substrate at 300 °C can eliminate oxygen contamination, but cannot completely remove carbon from the surface. Heating at higher temperatures decreases the carbon contamination only slightly, while increasing the Zn-Cd ratio on the surface considerably. The magnitude of the latter effect is surprising and is crucial when one is using lattice matched CdZnTe (Zn 4\%) substrates.}, language = {en} } @article{WuBeckerWaagetal.1993, author = {Wu, Y. S. and Becker, Charles R. and Waag, A. and Bicknell-Tassius, R. N. and Landwehr, G.}, title = {Removal of oxygen and reduction of carbon contamination on (100) Cd\(_{0.96}\)Zn\(_{0.04}\)Te}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-38014}, year = {1993}, abstract = {No abstract available}, language = {en} } @article{WuBeckerWaagetal.1991, author = {Wu, Y. S. and Becker, Charles R. and Waag, A. and Bicknell-Tassius, R. N. and Landwehr, G.}, title = {The effects of laser illumination and high energy electrons on molecular-beam epitaxial growth of CdTe}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30795}, year = {1991}, abstract = {We report the results of a detailed investigation on the Te-stabilized (2 x 1) and the Cdstabilized c( 2 X 2) surfaces of ( 100) CdTe substrates. The investigation demonstrates for the first time that both laser illumination and, to a greater extent, high-energy electron irradiation increase the Te desorption and reduce the Cd desorption from ( 100) CdTe surfaces. Thus it is possible by choosing the proper growth temperature and photon or electron fluxes to change the surface reconstruction from the normally Te-stabilized to a Cd-stabilized phase.}, language = {en} } @article{WuBeckerWaagetal.1993, author = {Wu, Y. S. and Becker, Charles R. and Waag, A. and Schmiedl, R. and Einfeldt, S. and Landwehr, G.}, title = {Oxygen on the (100) CdTe surface}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37869}, year = {1993}, abstract = {We have investigated oxygen on CdTe substrates by means of x-ray photoelectron spectroscopy (XPS) and reflection high-energy electron diffraction (RHEED). A Te oxide layer that was at least 15 A thick was found on the surface of as-delivered CdTe substrates that were mechanically polished. This oxide is not easily evaporated at temperatures lower than 350°C. Furthermore, heating in air, which further oxidizes the CdTe layer, should be avoided. Etching with HCI acid (15\% HCl) for at least 20 s and then rinsing with de-ionized water reduces the Te oxide layer on the surface down to 4\% of a monoatomic layer. However, according to XPS measurements of the 0 Is peak, 20\%-30\% of a monoatomic layer of oxygen remains on the surface, which can be eliminated by heating at temperatures ranging between 300 and 340 cC. The RHEED patterns for a molecular beam epitaxially (MBE)-grown CdTe film on a (lOO) CdTe substrate with approximately one monoatomic layer of oxidized Te on the surface lose the characteristics of the normal RHEED pattems for a MBE-grown CdTe film on an oxygen-free CdTe substrate.}, language = {en} } @article{WuBeckerWaagetal.1993, author = {Wu, Y. S. and Becker, Charles R. and Waag, A. and von Schierstedt, K. and Bicknell-Tassius, R. N. and Landwehr, G.}, title = {Surface sublimation of zinc blende CdTe}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37829}, year = {1993}, abstract = {The surface sublimation of Cd and Te atoms from the zinc blende (111)A CdTe surface has been investigated in detail by reflection high energy electron diffraction and x-ray photoelectron spectroscopy. These experiments verify that Te is much easier to evaporate than Cd. The experimental value for the Te activation energy from a Te stabilized (111)A CdTe surface is 1.41 ±0.1O eV, which is apparently inconsistent with recent theoretical results.}, language = {en} } @article{WuBeckerWaagetal.1991, author = {Wu, Y.S. and Becker, Charles R. and Waag, A. and Kraus, M. M. and Bicknell-Tassius, R. N. and Landwehr, G.}, title = {Correlation of the Cd-to-Te ratio on CdTe surfaces with the surface structure}, isbn = {0163-1829}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37789}, year = {1991}, abstract = {We report here that reconstruction on (100), (1lIlA, and (1l1lB CdTe surfaces is either C(2X2), (2X2), and (l X I) or (2X I), (l X I), and (l X I) when they are Cd or Te stabilized, respectively. There is a mixed region between Cd and Te stabilization in which the reflected high-energy electron-diffraction (RHEED) patterns contain characteristics of both Cd- and Te-stabilized surfaces. We have also found that the Cd-to-Te ratio of the x-ray photoelectron intensities of their 3d\(_{3/ 2}\) core levels is about 20\% larger for a Cd-stabilized (1lIlA, (1lIlB, or (100) CdTe surface than for a Te-stabilized one. According to a simple model calculation, which was normalized by means of the photoelectron intensity ratio of a Cd-stabilized (lll)A and aTe-stabilized (1l1lB CdTe surface, the experimental data for CdTe surfaces can be explained by a linear dependence of the photoelectron-intensity ratio on the fraction of Cd in the uppermost monatomic layer. This surface composition can be correlated with the surface structure, i.e., the corresponding RHEED patterns. This correlation can in turn be employed to determine Te and Cd evaporation rates. The Te reevaporation rate is increasingly slower for the Te-stabilized (Ill) A, (l1l)B, and (100) surfaces, while the opposite is true for Cd from Cd-stabilized (Ill) A and (Ill)B surfaces. In addition, Te is much more easily evaporated from all the investigated surfaces than is Cd, if the substrate is kept at normal molecular-beam-epitaxy growth temperatures ranging from 2oo·C to 300 ·C.}, subject = {Festk{\"o}rperphysik}, language = {en} } @article{WuPonsGoudetetal.2017, author = {Wu, Yu and Pons, Val{\´e}rie and Goudet, Am{\´e}lie and Panigai, Laetitia and Fischer, Annette and Herweg, Jo-Ana and Kali, Sabrina and Davey, Robert A. and Laporte, J{\´e}r{\^o}me and Bouclier, C{\´e}line and Yousfi, Rahima and Aubenque, C{\´e}line and Merer, Goulven and Gobbo, Emilie and Lopez, Roman and Gillet, Cynthia and Cojean, Sandrine and Popoff, Michel R. and Clayette, Pascal and Le Grand, Roger and Boulogne, Claire and Tordo, No{\"e}l and Lemichez, Emmanuel and Loiseau, Philippe M. and Rudel, Thomas and Sauvaire, Didier and Cintrat, Jean-Christophe and Gillet, Daniel and Barbier, Julien}, title = {ABMA, a small molecule that inhibits intracellular toxins and pathogens by interfering with late endosomal compartments}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, doi = {10.1038/s41598-017-15466-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173170}, year = {2017}, abstract = {Intracellular pathogenic microorganisms and toxins exploit host cell mechanisms to enter, exert their deleterious effects as well as hijack host nutrition for their development. A potential approach to treat multiple pathogen infections and that should not induce drug resistance is the use of small molecules that target host components. We identifed the compound 1-adamantyl (5-bromo-2-methoxybenzyl) amine (ABMA) from a cell-based high throughput screening for its capacity to protect human cells and mice against ricin toxin without toxicity. This compound efciently protects cells against various toxins and pathogens including viruses, intracellular bacteria and parasite. ABMA provokes Rab7-positive late endosomal compartment accumulation in mammalian cells without affecting other organelles (early endosomes, lysosomes, the Golgi apparatus, the endoplasmic reticulum or the nucleus). As the mechanism of action of ABMA is restricted to host-endosomal compartments, it reduces cell infection by pathogens that depend on this pathway to invade cells. ABMA may represent a novel class of broad-spectrum compounds with therapeutic potential against diverse severe infectious diseases.}, language = {en} } @phdthesis{Wu2022, author = {Wu, Zhu}, title = {Room Temperature Phosphorescence (RTP): Experimental And Theoretical Studies on Boron-Containing Materials}, doi = {10.25972/OPUS-26084}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260844}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Persistent room temperature phosphorescent (RTP) luminophores have gained remarkable interest recently for a number of applications in security printing, OLEDs, optical storage, time-gated biological imaging and oxygen sensors. We report the first persistent RTP with lifetimes up to 0.5 s from simple triarylboranes which have no lone pairs. We also have prepared 3 isomeric (o, m, p-bromophenyl)-bis(2,6-dimethylphenyl)boranes. Among the 3 isomers (o-, m- and p-BrTAB) synthesized, the ortho-one is the only one which shows dual phosphorescence, with a short lifetime of 0.8 ms and a long lifetime of 234 ms in the crystalline state at room temperature. At last, we checked the RTP properties from the boric acid. We found that the pure boric acid does not show RTP in the solid state.}, language = {en} } @article{WuDinkelbachKerneretal.2022, author = {Wu, Zhu and Dinkelbach, Fabian and Kerner, Florian and Friedrich, Alexandra and Ji, Lei and Stepanenko, Vladimir and W{\"u}rthner, Frank and Marian, Christel M. and Marder, Todd B.}, title = {Aggregation-Induced Dual Phosphorescence from (o-Bromophenyl)-Bis(2,6-Dimethylphenyl)Borane at Room Temperature}, series = {Chemistry—A European Journal}, volume = {28}, journal = {Chemistry—A European Journal}, number = {30}, doi = {10.1002/chem.202200525}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318297}, year = {2022}, abstract = {Designing highly efficient purely organic phosphors at room temperature remains a challenge because of fast non-radiative processes and slow intersystem crossing (ISC) rates. The majority of them emit only single component phosphorescence. Herein, we have prepared 3 isomers (o, m, p-bromophenyl)-bis(2,6-dimethylphenyl)boranes. Among the 3 isomers (o-, m- and p-BrTAB) synthesized, the ortho-one is the only one which shows dual phosphorescence, with a short lifetime of 0.8 ms and a long lifetime of 234 ms in the crystalline state at room temperature. Based on theoretical calculations and crystal structure analysis of o-BrTAB, the short lifetime component is ascribed to the T\(^M_1\) state of the monomer which emits the higher energy phosphorescence. The long-lived, lower energy phosphorescence emission is attributed to the T\(^A_1\) state of an aggregate, with multiple intermolecular interactions existing in crystalline o-BrTAB inhibiting nonradiative decay and stabilizing the triplet states efficiently.}, language = {en} } @article{WuNitschMarder2021, author = {Wu, Zhu and Nitsch, J{\"o}rn and Marder, Todd B.}, title = {Persistent room-temperature phosphorence from purely organic molecules and multi-component systems}, series = {Advanced Optical Materials}, volume = {9}, journal = {Advanced Optical Materials}, number = {20}, doi = {doi.org/10.1002/adom.202100411}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256415}, year = {2021}, abstract = {Recently, luminophores showing efficient room-temperature phosphorescence (RTP) have gained tremendous interest due to their numerous applications. However, most phosphors are derived from transition metal complexes because of their intrinsic fast intersystem crossing (ISC) induced by strong spin-orbit coupling (SOC) constants of the heavy metal. Metal-free RTP materials are rare and have become a promising field because they are inexpensive and environmentally friendly. This review summarizes organic molecular materials with long triplet lifetimes at room temperature from the perspective of whether they stem from a molecular or multi-component system. Among purely organic phosphors, heteroatoms are usually introduced into the backbone in order to boost the singlet-triplet ISC rate constant. In multi-component systems, useful strategies such as host-guest, polymer matrix, copolymerization, and supramolecular assembly provide a rigid matrix to restrict nonradiative pathways thus realizing ultralong RTP.}, language = {en} } @article{WuRoldaoRauchetal.2022, author = {Wu, Zhu and Roldao, Juan Carlos and Rauch, Florian and Friedrich, Alexandra and Ferger, Matthias and W{\"u}rthner, Frank and Gierschner, Johannes and Marder, Todd B.}, title = {Pure Boric Acid Does Not Show Room-Temperature Phosphorescence (RTP)}, series = {Angewandte Chemie}, volume = {61}, journal = {Angewandte Chemie}, number = {15}, doi = {10.1002/anie.202200599}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318308}, year = {2022}, abstract = {Boric acid (BA) has been used as a transparent glass matrix for optical materials for over 100 years. However, recently, apparent room-temperature phosphorescence (RTP) from BA (crystalline and powder states) was reported (Zheng et al., Angew. Chem. Int. Ed. 2021, 60, 9500) when irradiated at 280 nm under ambient conditions. We suspected that RTP from their BA sample was induced by an unidentified impurity. Our experimental results show that pure BA synthesized from B(OMe)\(_{3}\) does not luminesce in the solid state when irradiated at 250-400 nm, while commercial BA indeed (faintly) luminesces. Our theoretical calculations show that neither individual BA molecules nor aggregates would absorb light at >175 nm, and we observe no absorption of solid pure BA experimentally at >200 nm. Therefore, it is not possible for pure BA to be excited at >250 nm even in the solid state. Thus, pure BA does not display RTP, whereas trace impurities can induce RTP.}, language = {en} } @article{WulfBarkovitsSchorketal.2022, author = {Wulf, Maximilian and Barkovits, Katalin and Schork, Karin and Eisenacher, Martin and Riederer, Peter and Gerlach, Manfred and Eggers, Britta and Marcus, Katrin}, title = {The proteome of neuromelanin granules in dementia with Lewy bodies}, series = {Cells}, volume = {11}, journal = {Cells}, number = {22}, issn = {2073-4409}, doi = {10.3390/cells11223538}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297465}, year = {2022}, abstract = {Neuromelanin granules (NMGs) are organelle-like structures present in the human substantia nigra pars compacta. In addition to neuromelanin, NMGs contain proteins, lipids and metals. As NMG-containing dopaminergic neurons are preferentially lost in Parkinson's disease and dementia with Lewy bodies (DLB), it is assumed that NMGs may play a role in neurodegenerative processes. Until now, this role is not completely understood and needs further investigation. We therefore set up an exploratory proteomic study to identify differences in the proteomic profile of NMGs from DLB patients (n = 5) compared to healthy controls (CTRL, n = 5). We applied a laser microdissection and mass-spectrometry-based approach, in which we used targeted mass spectrometric experiments for validation. In NMG-surrounding (SN\(_{Surr.}\)) tissue of DLB patients, we found evidence for ongoing oxidative damage and an impairment of protein degradation. As a potentially disease-related mechanism, we found α-synuclein and protein S100A9 to be enriched in NMGs of DLB cases, while the abundance of several ribosomal proteins was significantly decreased. As S100A9 is known to be able to enhance the formation of toxic α-synuclein fibrils, this finding points towards an involvement of NMGs in pathogenesis, however the exact role of NMGs as either neuroprotective or neurotoxic needs to be further investigated. Nevertheless, our study provides evidence for an impairment of protein degradation, ongoing oxidative damage and accumulation of potentially neurotoxic protein aggregates to be central mechanisms of neurodegeneration in DLB.}, language = {en} } @article{WunderPempCeciletal.2022, author = {Wunder, Juliane and Pemp, Daniela and Cecil, Alexander and Mahdiani, Maryam and Hauptstein, Ren{\´e} and Schmalbach, Katja and Geppert, Leo N. and Ickstadt, Katja and Esch, Harald L. and Dankekar, Thomas and Lehmann, Leane}, title = {Influence of breast cancer risk factors on proliferation and DNA damage in human breast glandular tissues: role of intracellular estrogen levels, oxidative stress and estrogen biotransformation}, series = {Archives of Toxicology}, volume = {96}, journal = {Archives of Toxicology}, number = {2}, issn = {1432-0738}, doi = {10.1007/s00204-021-03198-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265343}, pages = {673-687}, year = {2022}, abstract = {Breast cancer etiology is associated with both proliferation and DNA damage induced by estrogens. Breast cancer risk factors (BCRF) such as body mass index (BMI), smoking, and intake of estrogen-active drugs were recently shown to influence intratissue estrogen levels. Thus, the aim of the present study was to investigate the influence of BCRF on estrogen-induced proliferation and DNA damage in 41 well-characterized breast glandular tissues derived from women without breast cancer. Influence of intramammary estrogen levels and BCRF on estrogen receptor (ESR) activation, ESR-related proliferation (indicated by levels of marker transcripts), oxidative stress (indicated by levels of GCLC transcript and oxidative derivatives of cholesterol), and levels of transcripts encoding enzymes involved in estrogen biotransformation was identified by multiple linear regression models. Metabolic fluxes to adducts of estrogens with DNA (E-DNA) were assessed by a metabolic network model (MNM) which was validated by comparison of calculated fluxes with data on methoxylated and glucuronidated estrogens determined by GC- and UHPLC-MS/MS. Intratissue estrogen levels significantly influenced ESR activation and fluxes to E-DNA within the MNM. Likewise, all BCRF directly and/or indirectly influenced ESR activation, proliferation, and key flux constraints influencing E-DNA (i.e., levels of estrogens, CYP1B1, SULT1A1, SULT1A2, and GSTP1). However, no unambiguous total effect of BCRF on proliferation became apparent. Furthermore, BMI was the only BCRF to indeed influence fluxes to E-DNA (via congruent adverse influence on levels of estrogens, CYP1B1 and SULT1A2).}, language = {en} } @article{WunschPfisterHenningetal.2016, author = {Wunsch, Kathrin and Pfister, Roland and Henning, Anne and Aschersleben, Gisa and Weigelt, Matthias}, title = {No Interrelation of Motor Planning and Executive Functions across Young Ages}, series = {Frontiers in Psychology}, volume = {7}, journal = {Frontiers in Psychology}, number = {1031}, doi = {10.3389/fpsyg.2016.01031}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165281}, year = {2016}, abstract = {The present study examined the developmental trajectories of motor planning and executive functioning in children. To this end, we tested 217 participants with three motor tasks, measuring anticipatory planning abilities (i.e., the bar-transport-task, the sword-rotation-task and the grasp-height-task), and three cognitive tasks, measuring executive functions (i.e., the Tower-of-Hanoi-task, the Mosaic-task, and the D2-attention-endurance-task). Children were aged between 3 and 10 years and were separated into age groups by 1-year bins, resulting in a total of eight groups of children and an additional group of adults. Results suggested (1) a positive developmental trajectory for each of the sub-tests, with better task performance as children get older; (2) that the performance in the separate tasks was not correlated across participants in the different age groups; and (3) that there was no relationship between performance in the motor tasks and in the cognitive tasks used in the present study when controlling for age. These results suggest that both, motor planning and executive functions are rather heterogeneous domains of cognitive functioning with fewer interdependencies than often suggested.}, language = {en} } @article{WunschCaspellKuertenetal.2015, author = {Wunsch, Marie and Caspell, Richard and Kuerten, Stefanie and Lehmann, Paul V. and Sundararaman, Srividya}, title = {Serial measurements of apoptotic cell numbers provide better acceptance criterion for PBMC quality than a single measurement prior to the T cell assay}, series = {Cells}, volume = {4}, journal = {Cells}, number = {1}, doi = {10.3390/cells4010040}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-150213}, pages = {40-55}, year = {2015}, abstract = {As soon as Peripheral Blood Mononuclear Cells (PBMC) are isolated from whole blood, some cells begin dying. The rate of apoptotic cell death is increased when PBMC are shipped, cryopreserved, or stored under suboptimal conditions. Apoptotic cells secrete cytokines that suppress inflammation while promoting phagocytosis. Increased numbers of apoptotic cells in PBMC may modulate T cell functions in antigen-triggered T cell assays. We assessed the effect of apoptotic bystander cells on a T cell ELISPOT assay by selectively inducing B cell apoptosis using α-CD20 mAbs. The presence of large numbers of apoptotic B cells did not affect T cell functionality. In contrast, when PBMC were stored under unfavorable conditions, leading to damage and apoptosis in the T cells as well as bystander cells, T cell functionality was greatly impaired. We observed that measuring the number of apoptotic cells before plating the PBMC into an ELISPOT assay did not reflect the extent of PBMC injury, but measuring apoptotic cell frequencies at the end of the assay did. Our data suggest that measuring the numbers of apoptotic cells prior to and post T cell assays may provide more stringent PBMC quality acceptance criteria than measurements done only prior to the start of the assay.}, language = {en} } @article{WunschHohmannMillesetal.2016, author = {Wunsch, Marie and Hohmann, Christopher and Milles, Bianca and Rostermund, Christina and Lehmann, Paul V. and Schroeter, Michael and Bayas, Antonios and Ulzheimer, Jochen and M{\"a}urer, Mathias and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie}, title = {The Correlation between the Virus- and Brain Antigen-Specific B Cell Response in the Blood of Patients with Multiple Sclerosis}, series = {Viruses}, volume = {8}, journal = {Viruses}, number = {4}, doi = {10.3390/v8040105}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146946}, pages = {105}, year = {2016}, abstract = {There is a largely divergent body of literature regarding the relationship between Epstein-Barr virus (EBV) infection and brain inflammation in multiple sclerosis (MS). Here, we tested MS patients during relapse (n = 11) and in remission (n = 19) in addition to n = 22 healthy controls to study the correlation between the EBV- and brain-specific B cell response in the blood by enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). Cytomegalovirus (CMV) was used as a control antigen tested in n = 16 MS patients during relapse and in n = 35 patients in remission. Over the course of the study, n = 16 patients were untreated, while n = 33 patients received immunomodulatory therapy. The data show that there was a moderate correlation between the frequencies of EBV- and brain-reactive B cells in MS patients in remission. In addition we could detect a correlation between the B cell response to EBV and disease activity. There was no evidence of an EBV reactivation. Interestingly, there was also a correlation between the frequencies of CMV- and brain-specific B cells in MS patients experiencing an acute relapse and an elevated B cell response to CMV was associated with higher disease activity. The trend remained when excluding seronegative subjects but was non-significant. These data underline that viral infections might impact the immunopathology of MS, but the exact link between the two entities remains subject of controversy.}, language = {en} } @article{WunschZhangHansonetal.2015, author = {Wunsch, Marie and Zhang, Wenji and Hanson, Jodi and Caspell, Richard and Karulin, Alexey Y. and Recks, Mascha S. and Kuerten, Stefanie and Sundararaman, Srividya and Lehmann, Paul V.}, title = {Characterization of the HCMV-Specific CD4 T Cell Responses that Are Associated with Protective Immunity}, series = {Viruses}, volume = {7}, journal = {Viruses}, doi = {10.3390/v7082828}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151462}, pages = {4414 -- 4437}, year = {2015}, abstract = {Most humans become infected with human cytomegalovirus (HCMV). Typically, the immune system controls the infection, but the virus persists and can reactivate in states of immunodeficiency. While substantial information is available on the contribution of CD8 T cells and antibodies to anti-HCMV immunity, studies of the T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 subsets have been limited by the low frequency of HCMV-specific CD4 T cells in peripheral blood mononuclear cell (PBMC). Using the enzyme-linked Immunospot\(^{®}\) assay (ELISPOT) that excels in low frequency measurements, we have established these in a sizable cohort of healthy HCMV controllers. Cytokine recall responses were seen in all seropositive donors. Specifically, interferon (IFN)-\({\gamma}\) and/or interleukin (IL)-17 were seen in isolation or with IL-4 in all test subjects. IL-4 recall did not occur in isolation. While the ratios of T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 cells exhibited substantial variations between different individuals these ratios and the frequencies were relatively stable when tested in samples drawn up to five years apart. IFN-\({\gamma}\) and IL-2 co-expressing polyfunctional cells were seen in most subjects. Around half of the HCMV-specific CD4 cells were in a reversible state of exhaustion. The data provided here established the T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 characteristic of the CD4 cells that convey immune protection for successful immune surveillance against which reactivity can be compared when the immune surveillance of HCMV fails.}, language = {en} } @article{WurdackLundtKlaasetal.2017, author = {Wurdack, Matthias and Lundt, Nils and Klaas, Martin and Baumann, Vasilij and Kavokin, Alexey V. and H{\"o}fling, Sven and Schneider, Christian}, title = {Observation of hybrid Tamm-plasmon exciton-polaritons with GaAs quantum wells and a MoSe\(_{2}\) monolayer}, series = {Nature Communications}, volume = {8}, journal = {Nature Communications}, number = {259}, doi = {10.1038/s41467-017-00155-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170480}, year = {2017}, abstract = {Strong light matter coupling between excitons and microcavity photons, as described in the framework of cavity quantum electrodynamics, leads to the hybridization of light and matter excitations. The regime of collective strong coupling arises, when various excitations from different host media are strongly coupled to the same optical resonance. This leads to a well-controllable admixture of various matter components in three hybrid polariton modes. Here, we study a cavity device with four embedded GaAs quantum wells hosting excitons that are spectrally matched to the A-valley exciton resonance of a MoSe\(_{2}\) monolayer. The formation of hybrid polariton modes is evidenced in momentum resolved photoluminescence and reflectivity studies. We describe the energy and k-vector distribution of exciton-polaritons along the hybrid modes by a thermodynamic model, which yields a very good agreement with the experiment.}, language = {en} } @article{WurmStarkZhuetal.2019, author = {Wurm, Michael and Stark, Thomas and Zhu, Xiao Xiang and Weigand, Matthias and Taubenb{\"o}ck, Hannes}, title = {Semantic segmentation of slums in satellite images using transfer learning on fully convolutional neural networks}, series = {ISPRS Journal of Photogrammetry and Remote Sensing}, volume = {150}, journal = {ISPRS Journal of Photogrammetry and Remote Sensing}, doi = {10.1016/j.isprsjprs.2019.02.006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233799}, pages = {59-69}, year = {2019}, abstract = {Unprecedented urbanization in particular in countries of the global south result in informal urban development processes, especially in mega cities. With an estimated 1 billion slum dwellers globally, the United Nations have made the fight against poverty the number one sustainable development goal. To provide better infrastructure and thus a better life to slum dwellers, detailed information on the spatial location and size of slums is of crucial importance. In the past, remote sensing has proven to be an extremely valuable and effective tool for mapping slums. The nature of used mapping approaches by machine learning, however, made it necessary to invest a lot of effort in training the models. Recent advances in deep learning allow for transferring trained fully convolutional networks (FCN) from one data set to another. Thus, in our study we aim at analyzing transfer learning capabilities of FCNs to slum mapping in various satellite images. A model trained on very high resolution optical satellite imagery from QuickBird is transferred to Sentinel-2 and TerraSAR-X data. While free-of-charge Sentinel-2 data is widely available, its comparably lower resolution makes slum mapping a challenging task. TerraSAR-X data on the other hand, has a higher resolution and is considered a powerful data source for intra-urban structure analysis. Due to the different image characteristics of SAR compared to optical data, however, transferring the model could not improve the performance of semantic segmentation but we observe very high accuracies for mapped slums in the optical data: QuickBird image obtains 86-88\% (positive prediction value and sensitivity) and a significant increase for Sentinel-2 applying transfer learning can be observed (from 38 to 55\% and from 79 to 85\% for PPV and sensitivity, respectively). Using transfer learning proofs extremely valuable in retrieving information on small-scaled urban structures such as slum patches even in satellite images of decametric resolution.}, language = {en} } @article{WurmbSchorscherJusticeetal.2018, author = {Wurmb, T and Schorscher, N and Justice, P and Dietz, S and Schua, R and Jarausch, T and Kinstle, U and Greiner, J and M{\"o}ldner, G and M{\"u}ller, J and Kraus, M and Simon, S and Wagenh{\"a}user, U and Hemm, J and Roewer, N and Helm, M}, title = {Structured analysis, evaluation and report of the emergency response to a terrorist attack in Wuerzburg, Germany using a new template of standardised quality indicators}, series = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, volume = {26}, journal = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, number = {87}, doi = {10.1186/s13049-018-0555-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177054}, year = {2018}, abstract = {Background: Until now there has been a reported lack of systematic reports and scientific evaluations of rescue missions during terror attacks. This however is urgently required in order to improve the performance of emergency medical services and to be able to compare different missions with each other. Aim of the presented work was to report the systematic evaluation and the lessons learned from the response to a terror attack that happened in Wuerzburg, Germany in 2016. Methods: A team of 14 experts developed a template of quality indicators and operational characteristics, which allow for the description, assessment and comparison of civil emergency rescue missions during mass killing incidents. The entire systematic evaluation process consisted of three main steps. The first step was the systematic data collection according to the quality indicators and operational characteristics. Second was the systematic stratification and assessment of the data. The last step was the prioritisation of the identified weaknesses and the definition of the lessons learned. Results: Five important "lessons learned" have been defined. First of all, a comprehensive concept for rescue missions during terror attacks is essential. Furthermore, the establishment of a defined high priority communication infrastructure between the different dispatch centres ("red phone") is vital. The goal is to secure the continuity of information between a few well-defined individuals. Thirdly, the organization of the incident scene needs to be commonly decided and communicated between police, medical services and fire services during the mission. A successful mission tactic requires continuous flux of reports to the on-site command post. Therefore, a predefined and common communication infrastructure for all operational forces is a crucial point. Finally, all strategies need to be extensively trained before the real life scenario hits. Conclusion: According to a systematic evaluation, we defined the lessons learned from a terror attack in 2016. Further systematic reports and academic work surrounding life threatening rescue missions and mass killing incidents are needed in order to ultimately improve such mission outcomes. In the future, a close international collaboration might help to find the best database to report and evaluate major incidents but also mass killing events.}, language = {en} } @article{WurmbSchlerethKredeletal.2014, author = {Wurmb, Thomas Erik and Schlereth, Stefan and Kredel, Markus and Muellenbach, Ralf M. and Wunder, Christian and Brederlau, J{\"o}rg and Roewer, Norbert and Kenn, Werner and Kunze, Ekkehard}, title = {Routine Follow-Up Cranial Computed Tomography for Deeply Sedated, Intubated, and Ventilated Multiple Trauma Patients with Suspected Severe Head Injury}, series = {BioMed Research International}, journal = {BioMed Research International}, number = {361949}, doi = {10.1155/2014/361949}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120084}, year = {2014}, abstract = {Background. Missed or delayed detection of progressive neuronal damage after traumatic brain injury (TBI) may have negative impact on the outcome. We investigated whether routine follow-up CT is beneficial in sedated and mechanically ventilated trauma patients. Methods. The study design is a retrospective chart review. A routine follow-up cCT was performed 6 hours after the admission scan. We defined 2 groups of patients, group I: patients with equal or recurrent pathologies and group II: patients with new findings or progression of known pathologies. Results. A progression of intracranial injury was found in 63 patients (42\%) and 18 patients (12\%) had new findings in cCT 2 (group II). In group II a change in therapy was found in 44 out of 81 patients (54\%). 55 patients with progression or new findings on the second cCT had no clinical signs of neurological deterioration. Of those 24 patients (44\%) had therapeutic consequences due to the results of the follow-up cCT. Conclusion. We found new diagnosis or progression of intracranial pathology in 54\% of the patients. In 54\% of patients with new findings and progression of pathology, therapy was changed due to the results of follow-up cCT. In trauma patients who are sedated and ventilated for different reasons a routine follow-up CT is beneficial.}, language = {en} } @article{WurmbFrankeSchorscheretal.2020, author = {Wurmb, Thomas and Franke, Axel and Schorscher, Nora and Kowalzik, Barbara and Helm, Matthias and Bohnen, Renate and Helmerichs, Jutta and Grueneisen, Ulrich and Cwojdzinski, Detlef and Jung, Georg and L{\"u}cking, Gesa and Weber, Martin}, title = {Emergency response to terrorist attacks: results of the federal-conducted evaluation process in Germany}, series = {European Journal of Trauma and Emergency Surgery}, volume = {46}, journal = {European Journal of Trauma and Emergency Surgery}, issn = {1863-9933}, doi = {10.1007/s00068-020-01347-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231777}, pages = {725-730}, year = {2020}, abstract = {Purpose Rescue missions during terrorist attacks are extremely challenging for all rescue forces (police as well as non-police forces) involved. To improve the quality and safety of the rescue missions during an active killing event, it is obligatory to adapt common rescue mission goals and strategies. Methods After the recent attacks in Europe, the Federal Office of Civil Protection and Disaster Assistance started an evaluation process on behalf of the Federal Ministry of the Interior and the Federal Ministry of Health. This was done to identify weaknesses, lessons learned and to formulate new adapted guidelines. Results The presented bullet point recommendations summarise the basic and most important results of the ongoing evaluation process for the Federal Republic of Germany. The safety of all the rescue forces and survival of the greatest possible number of casualties are the priority goals. Furthermore, the preservation and re-establishment of the socio-political integrity are the overarching goals of the management of active killing events. Strategic incident priorities are to stop the killing and to save as much lives as possible. The early identification and prioritised transportation of casualties with life-threatening non-controllable bleeding are major tasks and the shortest possible on-scene time is an important requirement with respect to safety issues. Conclusion With respect to hazard prevention tactics within Germany, we attributed the highest priority impact to the bullet points. The focus of the process has now shifted to intense work about possible solutions for the identified deficits and implementation strategies of such solutions during mass killing incidents.}, language = {en} } @article{WurmbScholtesKolibayetal.2020, author = {Wurmb, Thomas and Scholtes, Katja and Kolibay, Felix and Schorscher, Nora and Ertl, Georg and Ernestus, Ralf-Ingo and Vogel, Ulrich and Franke, Axel and Kowalzik, Barbara}, title = {Hospital preparedness for mass critical care during SARS-CoV-2 pandemic}, series = {Critical Care}, volume = {24}, journal = {Critical Care}, doi = {10.1186/s13054-020-03104-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230201}, year = {2020}, abstract = {Mass critical care caused by the severe acute respiratory syndrome corona virus 2 pandemic poses an extreme challenge to hospitals. The primary goal of hospital disaster preparedness and response is to maintain conventional or contingency care for as long as possible. Crisis care must be delayed as long as possible by appropriate measures. Increasing the intensive care unit (ICU) capacities is essential. In order to adjust surge capacity, the reduction of planned, elective patient care is an adequate response. However, this involves numerous problems that must be solved with a sense of proportion. This paper summarises preparedness and response measures recommended to acute care hospitals.}, language = {en} } @article{WurmbVollmerSefrinetal.2015, author = {Wurmb, Thomas and Vollmer, Tina and Sefrin, Peter and Kraus, Martin and Happel, Oliver and Wunder, Christian and Steinisch, Andrias and Roewer, Norbert and Maier, Sebastian}, title = {Monitoring of in-hospital cardiac arrest events with the focus on Automated External Defibrillators - a retrospective observational study}, series = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, volume = {23}, journal = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, number = {87}, doi = {10.1186/s13049-015-0170-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125756}, year = {2015}, abstract = {Background Patients with cardiac arrest have lower survival rates, when resuscitation performance is low. In In-hospital settings the first responders on scene are usually nursing staff without rhythm analysing skills. In such cases Automated External Defibrillators (AED) might help guiding resuscitation performance. At the Wuerzburg University Hospital (Germany) an AED-program was initiated in 2007. Aim of the presented study was to monitor the impact of Automated External Defibrillators on the management of in-hospital cardiac arrest events. Methods The data acquisition was part of a continuous quality improvement process of the Wuerzburg University Hospital. For analysing the CPR performance, the chest compression rate (CCR), compression depth (CCD), the no flow fraction (NFF), time interval from AED-activation to the first compression (TtC), the time interval from AED-activation to the first shock (TtS) and the post schock pause (TtCS) were determined by AED captured data. A questionnaire was completed by the first responders. Results From 2010 to 2012 there were 359 emergency calls. From these 53 were cardiac arrests with an AED-application. Complete data were available in 46 cases. The TtC was 34 (32-52) seconds (median and IQR).The TtS was 30 (28-32) seconds (median and IQR) . The TtCS was 4 (3-6) seconds (median and IQR) . The CCD was 5.5 ± 1 cm while the CCR was 107 ± 11/min. The NFF was calculated as 41 \%. ROSC was achieved in 21 patients (45 \%), 8 patients (17 \%) died on scene and 17 patients (37 \%) were transferred under ongoing CPR to an Intensive Care Unit (ICU). Conclusion The TtS and TtC indicate that there is an AED-user dependent time loss. These time intervals can be markedly reduced, when the user is trained to interrupt the AED's "chain of advices" by placing the electrode-paddles immediately on the patient's thorax. At this time the AED switches directly to the analysing mode. Intensive training and adaption of the training contents is needed to optimize the handling of the AED in order to maximize its advantages and to minimize its disadvantages.}, language = {en} } @phdthesis{Wurst2015, author = {Wurst, Jan-Eric}, title = {Hp-Finite Elements for PDE-Constrained Optimization}, publisher = {W{\"u}rzburg University Press}, address = {W{\"u}rzburg}, isbn = {978-3-95826-024-5 (print)}, doi = {10.25972/WUP-978-3-95826-025-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115027}, school = {W{\"u}rzburg University Press}, pages = {188}, year = {2015}, abstract = {Diese Arbeit behandelt die hp-Finite Elemente Methode (FEM) f{\"u}r linear quadratische Optimal-steuerungsprobleme. Dabei soll ein Zielfunktional, welches die Entfernung zu einem angestrebten Zustand und hohe Steuerungskosten (als Regularisierung) bestraft, unter der Nebenbedingung einer elliptischen partiellen Differentialgleichung minimiert werden. Bei der Anwesenheit von Steuerungsbeschr{\"a}nkungen k{\"o}nnen die notwendigen Bedingungen erster Ordnung, die typischerweise f{\"u}r numerische L{\"o}sungsverfahren genutzt werden, als halbglatte Projektionsformel formuliert werden. Folglich sind optimale L{\"o}sungen oftmals auch nicht-glatt. Die Technik der hp-Diskretisierung ber{\"u}cksichtigt diese Tatsache und approximiert raue Funktionen auf feinen Gittern, w{\"a}hrend Elemente h{\"o}herer Ordnung auf Gebieten verwendet werden, auf denen die L{\"o}sung glatt ist. Die erste Leistung dieser Arbeit ist die erfolgreiche Anwendung der hp-FEM auf zwei verwandte Problemklassen: Neumann- und Interface-Steuerungsprobleme. Diese werden zun{\"a}chst mit entsprechenden a-priori Verfeinerungsstrategien gel{\"o}st, mit der randkonzentrierten (bc) FEM oder interface konzentrierten (ic) FEM. Diese Strategien generieren Gitter, die stark in Richtung des Randes beziehungsweise des Interfaces verfeinert werden. Um f{\"u}r beide Techniken eine algebraische Reduktion des Approximationsfehlers zu beweisen, wird eine elementweise interpolierende Funktion konstruiert. Außerdem werden die lokale und globale Regularit{\"a}t von L{\"o}sungen behandelt, weil sie entscheidend f{\"u}r die Konvergenzgeschwindigkeit ist. Da die bc- und ic- FEM kleine Polynomgrade f{\"u}r Elemente verwenden, die den Rand beziehungsweise das Interface ber{\"u}hren, k{\"o}nnen eine neue L2- und L∞-Fehlerabsch{\"a}tzung hergeleitet werden. Letztere bildet die Grundlage f{\"u}r eine a-priori Strategie zum Aufdatieren des Regularisierungsparameters im Zielfunktional, um Probleme mit bang-bang Charakter zu l{\"o}sen. Zudem wird die herk{\"o}mmliche hp-Idee, die daraus besteht das Gitter geometrisch in Richtung der Ecken des Gebiets abzustufen, auf die L{\"o}sung von Optimalsteuerungsproblemen {\"u}bertragen (vc-FEM). Es gelingt, Regularit{\"a}t in abz{\"a}hlbar normierten R{\"a}umen f{\"u}r die Variablen des gekoppelten Optimalit{\"a}tssystems zu zeigen. Hieraus resultiert die exponentielle Konvergenz im Bezug auf die Anzahl der Freiheitsgrade. Die zweite Leistung dieser Arbeit ist die Entwicklung einer v{\"o}llig adaptiven hp-Innere-Punkte-Methode, die Probleme mit verteilter oder Neumann Steuerung l{\"o}sen kann. Das zugrundeliegende Barriereproblem besitzt ein nichtlineares Optimilit{\"a}tssystem, das eine numerische Herausforderung beinhaltet: die stabile Berechnung von Integralen {\"u}ber Funktionen mit m{\"o}glichen Singularit{\"a}ten in Elementen h{\"o}herer Ordnung. Dieses Problem wird dadurch gel{\"o}st, dass die Steuerung an den Integrationspunkten {\"u}berwacht wird. Die Zul{\"a}ssigkeit an diesen Punkten wird durch einen Gl{\"a}ttungsschritt garantiert. In dieser Arbeit werden sowohl die Konvergenz eines Innere-Punkte-Verfahrens mit Gl{\"a}ttungsschritt als auch a-posteriori Schranken f{\"u}r den Diskretisierungsfehler gezeigt. Dies f{\"u}hrt zu einem adaptiven L{\"o}sungsalgorithmus, dessen Gitterverfeinerung auf der Entwicklung der L{\"o}sung in eine Legendre Reihe basiert. Hierbei dient das Abklingverhalten der Koeffizienten als Glattheitsindikator und wird f{\"u}r die Entscheidung zwischen h- und p-Verfeinerung herangezogen.}, subject = {Finite-Elemente-Methode}, language = {en} } @article{WutzlerKrogiasGrauetal.2019, author = {Wutzler, Alexander and Krogias, Christos and Grau, Anna and Veltkamp, Roland and Heuschmann, Peter U. and Haeusler, Karl Georg}, title = {Stroke prevention in patients with acute ischemic stroke and atrial fibrillation in Germany - a cross sectional survey}, series = {BMC Neurology}, volume = {19}, journal = {BMC Neurology}, doi = {10.1186/s12883-019-1249-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201078}, pages = {25}, year = {2019}, abstract = {Background Atrial fibrillation (AF) is present in 15-20\% of patients with acute ischemic stroke. Oral anticoagulation reduces the risk of AF-related recurrent stroke but clinical guideline recommendations are rather vague regarding its use in the acute phase of stroke. We aimed to assess the current clinical practice of medical stroke prevention in AF patients during the acute phase of ischemic stroke. Methods In April 2017, a standardized anonymous questionnaire was sent to clinical leads of all 298 certified stroke units in Germany. Results Overall, 154 stroke unit leads participated (response rate 52\%). Anticoagulation in the acute phase of stroke is considered feasible in more than 90\% of AF patients with ischemic stroke. Clinicians assume that about two thirds of all AF patients (range 20-100\%) are discharged on oral anticoagulation. According to local preferences, acetylsalicylic acid is given orally in the majority of patients with delayed initiation of oral anticoagulation. A non-vitamin K-dependent oral anticoagulant (NOAC) is more often prescribed than a vitamin K-dependent oral anticoagulant (VKA). VKA is more often chosen in patients with previous VKA intake than in VKA naive patients. In the minority of patients, stroke unit leads discuss the prescription of a specific oral anticoagulant with the treating general practitioner. Adherence to medical stroke prevention after hospital discharge is not assessed on a regular basis in any patient by the majority of participating stroke centers. Conclusions Early secondary stroke prevention in AF patients in German stroke units is based on OAC use but prescription modalities vary in clinical practice.}, language = {en} } @article{WussmannGroeberBeckerRiedletal.2022, author = {Wußmann, Maximiliane and Groeber-Becker, Florian Kai and Riedl, Sabrina and Alihodzic, Dina and Padaric, Daniel and Gerlitz, Lisa and Stallinger, Alexander and Liegl-Atzwanger, Bernadette and Zweytick, Dagmar and Rinner, Beate}, title = {In model, in vitro and in vivo killing efficacy of antitumor peptide RDP22 on MUG-Mel2, a patient derived cell line of an aggressive melanoma metastasis}, series = {Biomedicines}, volume = {10}, journal = {Biomedicines}, number = {11}, issn = {2227-9059}, doi = {10.3390/biomedicines10112961}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297525}, year = {2022}, abstract = {The host defense derived peptide was assessed in different model systems with increasing complexity employing the highly aggressive NRAS mutated melanoma metastases cell line MUG-Mel2. Amongst others, fluorescence microscopy and spectroscopy, as well as cell death studies were applied for liposomal, 2D and 3D in vitro models including tumor spheroids without or within skin models and in vivo mouse xenografts. Summarized, MUG-Mel2 cells were shown to significantly expose the negatively charged lipid phosphatidylserine on their plasma membranes, showing they are successfully targeted by RDP22. The peptide was able to induce cell death in MUG-Mel2 2D and 3D cultures, where it was able to kill tumor cells even inside the core of tumor spheroids or inside a melanoma organotypic model. In vitro studies indicated cell death by apoptosis upon peptide treatment with an LC\(_{50}\) of 8.5 µM and seven-fold specificity for the melanoma cell line MUG-Mel2 over normal dermal fibroblasts. In vivo studies in mice xenografts revealed effective tumor regression upon intratumoral peptide injection, indicated by the strong clearance of pigmented tumor cells and tremendous reduction in tumor size and proliferation, which was determined histologically. The peptide RDP22 has clearly shown high potential against the melanoma cell line MUG-Mel2 in vitro and in vivo.}, language = {en} } @article{WyborskiMusiałMrowińskietal.2021, author = {Wyborski, Paweł and Musiał, Anna and Mrowiński, Paweł and Podemski, Paweł and Baumann, Vasilij and Wroński, Piotr and Jabeen, Fauzia and H{\"o}fling, Sven and Sęk, Grzegorz}, title = {InP-substrate-based quantum dashes on a DBR as single-photon emitters at the third telecommunication window}, series = {Materials}, volume = {14}, journal = {Materials}, number = {4}, issn = {1996-1944}, doi = {10.3390/ma14040759}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228773}, year = {2021}, abstract = {We investigated emission properties of photonic structures with InAs/InGaAlAs/InP quantum dashes grown by molecular beam epitaxy on a distributed Bragg reflector. In high-spatial-resolution photoluminescence experiment, well-resolved sharp spectral lines are observed and single-photon emission is detected in the third telecommunication window characterized by very low multiphoton events probabilities. The photoluminescence spectra measured on simple photonic structures in the form of cylindrical mesas reveal significant intensity enhancement by a factor of 4 when compared to a planar sample. These results are supported by simulations of the electromagnetic field distribution, which show emission extraction efficiencies even above 18\% for optimized designs. When combined with relatively simple and undemanding fabrication approach, it makes this kind of structures competitive with the existing solutions in that spectral range and prospective in the context of efficient and practical single-photon sources for fiber-based quantum networks applications.}, language = {en} } @article{WyborskiPodemskiWrońskietal.2022, author = {Wyborski, Paweł and Podemski, Paweł and Wroński, Piotr Andrzej and Jabeen, Fauzia and H{\"o}fling, Sven and Sęk, Grzegorz}, title = {Electronic and optical properties of InAs QDs grown by MBE on InGaAs metamorphic buffer}, series = {Materials}, volume = {15}, journal = {Materials}, number = {3}, issn = {1996-1944}, doi = {10.3390/ma15031071}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297037}, year = {2022}, abstract = {We present the optical characterization of GaAs-based InAs quantum dots (QDs) grown by molecular beam epitaxy on a digitally alloyed InGaAs metamorphic buffer layer (MBL) with gradual composition ensuring a redshift of the QD emission up to the second telecom window. Based on the photoluminescence (PL) measurements and numerical calculations, we analyzed the factors influencing the energies of optical transitions in QDs, among which the QD height seems to be dominating. In addition, polarization anisotropy of the QD emission was observed, which is a fingerprint of significant valence states mixing enhanced by the QD confinement potential asymmetry, driven by the decreased strain with increasing In content in the MBL. The barrier-related transitions were probed by photoreflectance, which combined with photoluminescence data and the PL temperature dependence, allowed for the determination of the carrier activation energies and the main channels of carrier loss, identified as the carrier escape to the MBL barrier. Eventually, the zero-dimensional character of the emission was confirmed by detecting the photoluminescence from single QDs with identified features of the confined neutral exciton and biexciton complexes via the excitation power and polarization dependences.}, language = {en} } @article{WylerMenegattiFrankeetal.2017, author = {Wyler, Emanuel and Menegatti, Jennifer and Franke, Vedran and Kocks, Christine and Boltengagen, Anastasiya and Hennig, Thomas and Theil, Kathrin and Rutkowski, Andrzej and Ferrai, Carmelo and Baer, Laura and Kermas, Lisa and Friedel, Caroline and Rajewsky, Nikolaus and Akalin, Altuna and D{\"o}lken, Lars and Gr{\"a}sser, Friedrich and Landthaler, Markus}, title = {Widespread activation of antisense transcription of the host genome during herpes simplex virus 1 infection}, series = {Genome Biology}, volume = {18}, journal = {Genome Biology}, doi = {10.1186/s13059-017-1329-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173381}, year = {2017}, abstract = {Background Herpesviruses can infect a wide range of animal species. Herpes simplex virus 1 (HSV-1) is one of the eight herpesviruses that can infect humans and is prevalent worldwide. Herpesviruses have evolved multiple ways to adapt the infected cells to their needs, but knowledge about these transcriptional and post-transcriptional modifications is sparse. Results Here, we show that HSV-1 induces the expression of about 1000 antisense transcripts from the human host cell genome. A subset of these is also activated by the closely related varicella zoster virus. Antisense transcripts originate either at gene promoters or within the gene body, and they show different susceptibility to the inhibition of early and immediate early viral gene expression. Overexpression of the major viral transcription factor ICP4 is sufficient to turn on a subset of antisense transcripts. Histone marks around transcription start sites of HSV-1-induced and constitutively transcribed antisense transcripts are highly similar, indicating that the genetic loci are already poised to transcribe these novel RNAs. Furthermore, an antisense transcript overlapping with the BBC3 gene (also known as PUMA) transcriptionally silences this potent inducer of apoptosis in cis. Conclusions We show for the first time that a virus induces widespread antisense transcription of the host cell genome. We provide evidence that HSV-1 uses this to downregulate a strong inducer of apoptosis. Our findings open new perspectives on global and specific alterations of host cell transcription by viruses.}, language = {en} } @article{WaechtlerKuebelBarthelmesetal.2016, author = {W{\"a}chtler, Maria and K{\"u}bel, Joachim and Barthelmes, Kevin and Winter, Andreas and Schmiedel, Alexander and Pascher, Torbj{\"o}rn and Lambert, Christoph and Schubert, Ulrich S. and Dietzek, Benjamin}, title = {Energy transfer and formation of long-lived \(^3\)MLCT states in multimetallic complexes with extended highly conjugated bis-terpyridyl ligands}, series = {Physical Chemistry Chemical Physics}, volume = {18}, journal = {Physical Chemistry Chemical Physics}, number = {4}, doi = {10.1039/c5cp04447b}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191041}, pages = {2350-2360}, year = {2016}, abstract = {Multimetallic complexes with extended and highly conjugated bis-2,2':6',2''-terpyridyl bridging ligands, which present building blocks for coordination polymers, are investigated with respect to their ability to act as light-harvesting antennae. The investigated species combine Ru(II)- with Os(II)- and Fe(II)-terpyridyl chromophores, the latter acting as energy sinks. Due to the extended conjugated system the ligands are able to prolong the lifetime of the \(^3\)MLCT states compared to unsubstituted terpyridyl species by delocalization and energetic stabilization of the \(^3\)MLCT states. This concept is applied for the first time to Fe(II) terpyridyl species and results in an exceptionally long lifetime of 23 ps for the Fe(II) \(^3\)MLCT state. While partial energy (>80\%) transfer is observed between the Ru(II) and Fe(II) centers with a time-constant of 15 ps, excitation energy is transferred completely from the Ru(II) to the Os(II) center within the first 200 fs after excitation.}, language = {en} } @phdthesis{Waeldchen2020, author = {W{\"a}ldchen, Felix}, title = {3D Single Molecule Imaging In Whole Cells Enabled By Lattice Light-Sheet Illumination}, doi = {10.25972/OPUS-20711}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207111}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Single molecule localization microscopy has seen a remarkable growth since its first experimental implementations about a decade ago. Despite its technical challenges, it is already widely used in medicine and biology and is valued as a unique tool to gain molecular information with high specificity. However, common illumination techniques do not allow the use of single molecule sensitive super-resolution microscopy techniques such as direct stochastic optical reconstruction microscopy (dSTORM) for whole cell imaging. In addition, they can potentially alter the quantitative information. In this thesis, I combine dSTORM imaging in three dimensions with lattice lightsheet illumination to gain quantitative molecular information from cells unperturbed by the illumination and cover slip effects. Lattice light-sheet illumination uses optical lattices for beam shaping to restrict the illumination to the detectable volume. I describe the theoretical background needed for both techniques and detail the experimental realization of the system as well as the software that I developed to efficiently evaluate the data. Eventually, I will present key datasets that demonstrate the capabilities of the developed microscope system with and without dSTORM. My main goal here was to use these techniques for imaging the neural cell adhesion molecule (NCAM, also known as CD56) in whole cells. NCAM is a plasma membrane receptor known to play a key role in biological processes such as memory and learning. Combining dSTORM and lattice light-sheet illumination enables the collection of quantitative data of the distribution of molecules across the whole plasma membrane, and shows an accumulation of NCAM at cell-cell interfaces. The low phototoxicity of lattice light-sheet illumination further allows for tracking individual NCAM dimers in living cells, showing a significant dependence of its mobility on the actin skeleton of the cell.}, subject = {Einzelmolek{\"u}lmikroskopie}, language = {en} } @article{WaeldchenLehmannKleinetal.2015, author = {W{\"a}ldchen, Sina and Lehmann, Julian and Klein, Teresa and van de Linde, Sebastian and Sauer, Markus}, title = {Light-induced cell damage in live-cell super-resolution microscopy}, series = {Scientific Reports}, volume = {5}, journal = {Scientific Reports}, number = {15348}, doi = {10.1038/srep15348}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145207}, year = {2015}, abstract = {Super-resolution microscopy can unravel previously hidden details of cellular structures but requires high irradiation intensities to use the limited photon budget efficiently. Such high photon densities are likely to induce cellular damage in live-cell experiments. We applied single-molecule localization microscopy conditions and tested the influence of irradiation intensity, illumination-mode, wavelength, light-dose, temperature and fluorescence labeling on the survival probability of different cell lines 20-24 hours after irradiation. In addition, we measured the microtubule growth speed after irradiation. The photo-sensitivity is dramatically increased at lower irradiation wavelength. We observed fixation, plasma membrane permeabilization and cytoskeleton destruction upon irradiation with shorter wavelengths. While cells stand light intensities of similar to 1 kW cm\(^{-2}\) at 640 nm for several minutes, the maximum dose at 405 nm is only similar to 50 J cm\(^{-2}\), emphasizing red fluorophores for live-cell localization microscopy. We also present strategies to minimize phototoxic factors and maximize the cells ability to cope with higher irradiation intensities.}, language = {en} } @article{WaeschkeHardgeHancocketal.2014, author = {W{\"a}schke, Nicole and Hardge, Kerstin and Hancock, Christine and Hilker, Monika and Obermaier, Elisabeth and Meiners, Torsten}, title = {Odour Environments: How Does Plant Diversity Affect Herbivore and Parasitoid Orientation?}, series = {PlOS ONE}, volume = {9}, journal = {PlOS ONE}, number = {1}, issn = {1932-6203}, doi = {10.1371/journal.pone.0085152}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117687}, pages = {e85152}, year = {2014}, abstract = {Plant diversity is known to affect success of host location by pest insects, but its effect on olfactory orientation of non-pest insect species has hardly been addressed. First, we tested in laboratory experiments the hypothesis that non-host plants, which increase odour complexity in habitats, affect the host location ability of herbivores and parasitoids. Furthermore, we recorded field data of plant diversity in addition to herbivore and parasitoid abundance at 77 grassland sites in three different regions in Germany in order to elucidate whether our laboratory results reflect the field situation. As a model system we used the herb Plantago lanceolata, the herbivorous weevil Mecinus pascuorum, and its larval parasitoid Mesopolobus incultus. The laboratory bioassays revealed that both the herbivorous weevil and its larval parasitoid can locate their host plant and host via olfactory cues even in the presence of non-host odour. In a newly established two-circle olfactometer, the weevils capability to detect host plant odour was not affected by odours from non-host plants. However, addition of non-host plant odours to host plant odour enhanced the weevils foraging activity. The parasitoid was attracted by a combination of host plant and host volatiles in both the absence and presence of non-host plant volatiles in a Y-tube olfactometer. In dual choice tests the parasitoid preferred the blend of host plant and host volatiles over its combination with non-host plant volatiles. In the field, no indication was found that high plant diversity disturbs host (plant) location by the weevil and its parasitoid. In contrast, plant diversity was positively correlated with weevil abundance, whereas parasitoid abundance was independent of plant diversity. Therefore, we conclude that weevils and parasitoids showed the sensory capacity to successfully cope with complex vegetation odours when searching for hosts.}, language = {en} } @article{WoelfelSaetteleZechmeisteretal.2020, author = {W{\"o}lfel, Angela and S{\"a}ttele, Mathias and Zechmeister, Christina and Nikolaev, Viacheslov O. and Lohse, Martin J. and Boege, Fritz and Jahns, Roland and Boivin-Jahns, Val{\´e}rie}, title = {Unmasking features of the auto-epitope essential for β\(_1\)-adrenoceptor activation by autoantibodies in chronic heart failure}, series = {ESC Heart Failure}, volume = {7}, journal = {ESC Heart Failure}, number = {4}, doi = {10.1002/ehf2.12747}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235974}, pages = {1830-1841}, year = {2020}, abstract = {Aims Chronic heart failure (CHF) can be caused by autoantibodies stimulating the heart via binding to first and/or second extracellular loops of cardiac β1-adrenoceptors. Allosteric receptor activation depends on conformational features of the autoantibody binding site. Elucidating these features will pave the way for the development of specific diagnostics and therapeutics. Our aim was (i) to fine-map the conformational epitope within the second extracellular loop of the human β\(_1\)-adrenoceptor (β1ECII) that is targeted by stimulating β\(_1\)-receptor (auto)antibodies and (ii) to generate competitive cyclopeptide inhibitors of allosteric receptor activation, which faithfully conserve the conformational auto-epitope. Methods and results Non-conserved amino acids within the β\(_1\)EC\(_{II}\) loop (compared with the amino acids constituting the ECII loop of the β\(_2\)-adrenoceptor) were one by one replaced with alanine; potential intra-loop disulfide bridges were probed by cysteine-serine exchanges. Effects on antibody binding and allosteric receptor activation were assessed (i) by (auto)antibody neutralization using cyclopeptides mimicking β1ECII ± the above replacements, and (ii) by (auto)antibody stimulation of human β\(_1\)-adrenoceptors bearing corresponding point mutations. With the use of stimulating β\(_1\)-receptor (auto)antibodies raised in mice, rats, or rabbits and isolated from exemplary dilated cardiomyopathy patients, our series of experiments unmasked two features of the β\(_1\)EC\(_{II}\) loop essential for (auto)antibody binding and allosteric receptor activation: (i) the NDPK\(^{211-214}\) motif and (ii) the intra-loop disulfide bond C\(^{209}\)↔C\(^{215}\). Of note, aberrant intra-loop disulfide bond C\(^{209}\)↔C\(^{216}\) almost fully disrupted the functional auto-epitope in cyclopeptides. Conclusions The conformational auto-epitope targeted by cardio-pathogenic β\(_1\)-receptor autoantibodies is faithfully conserved in cyclopeptide homologues of the β\(_1\)EC\(_{II}\) loop bearing the NDPK\(^{211-214}\) motif and the C\(^{209}\)↔C\(^{215}\) bridge while lacking cysteine C216. Such molecules provide promising tools for novel diagnostic and therapeutic approaches in β\(_1\)-autoantibodypositive CHF.}, language = {en} } @article{WoelflingBeckerUhletal.2016, author = {W{\"o}lfling, Mirko and Becker, Mira C. and Uhl, Britta and Traub, Anja and Fiedler, Konrad}, title = {How differences in the settling behaviour of moths (Lepidoptera) may contribute to sampling bias when using automated light traps}, series = {European Journal of Entomology}, volume = {113}, journal = {European Journal of Entomology}, doi = {10.14411/eje.2016.066}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191154}, pages = {502-506}, year = {2016}, abstract = {Quantitative community-wide moth surveys frequently employ flight-interception traps equipped with UV-light emitting sources as attractants. It has long been known that moth species differ in their responsiveness to light traps. We studied how the settling behaviour of moths at a light trap may further contribute to sampling bias. We observed the behaviour of 1426 moths at a light tower. Moths were classified as either, settling and remaining still after arrival, or continually moving on the gauze for extended periods of time. Moths that did not move after settling may not end up in the sampling container of the light trap and therefore are under-represented in automated trap samples relative to their true proportions in the community. Our analyses revealed highly significant behavioural differences between moths that differed in body size. Small moths were more likely to remain stationary after settling. As a corollary, representatives of three taxa, which in Europe are predominantly small species (Nolidae, Geometridae: Eupitheciini, Erebidae: Lithosiini), usually settled down immediately, whereas most other moths remained active on or flying around the trap for some time. Moth behaviour was also modulated by ambient temperature. At high temperatures, they were less likely to settle down immediately, but this behavioural difference was most strongly apparent among medium-sized moths. These results indicate the likely extent of the sampling bias when analysing and interpreting automated light-trap samples. Furthermore, to control for temperature modulated sampling bias temperature should always be recorded when sampling moths using flight-interception traps.}, language = {en} } @article{WoelkSuetterlinKochetal.2014, author = {W{\"o}lk, Julian and S{\"u}tterlin, Stefan and Koch, Stefan and V{\"o}gele, Claus and Schulz, Stefan M.}, title = {Enhanced cardiac perception predicts impaired performance in the Iowa Gambling Task in patients with panic disorder}, series = {Brain and Behavior}, volume = {4}, journal = {Brain and Behavior}, number = {2}, issn = {2162-3279}, doi = {10.1002/brb3.206}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119865}, pages = {238-46}, year = {2014}, abstract = {OBJECTIVE: Somatic marker theory predicts that somatic cues serve intuitive decision making; however, cardiovascular symptoms are threat cues for patients with panic disorder (PD). Therefore, enhanced cardiac perception may aid intuitive decision making only in healthy individuals, but impair intuitive decision making in PD patients. METHODS: PD patients and age-and sex-matched volunteers without a psychiatric diagnosis (n=17, respectively) completed the Iowa Gambling Task (IGT) as a measure of intuitive decision making. Interindividual differences in cardiac perception were assessed with a common mental-tracking task. RESULTS: In line with our hypothesis, we found a pattern of opposing associations (Fisher's Z=1.78, P=0.04) of high cardiac perception with improved IGT-performance in matched control-participants (r=0.36, n=14) but impaired IGT-performance in PD patients (r=-0.38, n=13). CONCLUSION: Interoceptive skills, typically assumed to aid intuitive decision making, can have the opposite effect in PD patients who experience interoceptive cues as threatening, and tend to avoid them. This may explain why PD patients frequently have problems with decision making in everyday life. Screening of cardiac perception may help identifying patients who benefit from specifically tailored interventions.}, language = {en} } @article{WoersdoerferDaldaKernetal.2019, author = {W{\"o}rsd{\"o}rfer, Philipp and Dalda, Nahide and Kern, Anna and Kr{\"u}ger, Sarah and Wagner, Nicole and Kwok, Chee Keong and Henke, Erik and Erg{\"u}n, S{\"u}leyman}, title = {Generation of complex human organoid models including vascular networks by incorporation of mesodermal progenitor cells}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-52204-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202681}, pages = {15663}, year = {2019}, abstract = {Organoids derived from human pluripotent stem cells are interesting models to study mechanisms of morphogenesis and promising platforms for disease modeling and drug screening. However, they mostly remain incomplete as they lack stroma, tissue resident immune cells and in particular vasculature, which create important niches during development and disease. We propose, that the directed incorporation of mesodermal progenitor cells (MPCs) into organoids will overcome the aforementioned limitations. In order to demonstrate the feasibility of the method, we generated complex human tumor as well as neural organoids. We show that the formed blood vessels display a hierarchic organization and mural cells are assembled into the vessel wall. Moreover, we demonstrate a typical blood vessel ultrastructure including endothelial cell-cell junctions, a basement membrane as well as luminal caveolae and microvesicles. We observe a high plasticity in the endothelial network, which expands, while the organoids grow and is responsive to anti-angiogenic compounds and pro-angiogenic conditions such as hypoxia. We show that vessels within tumor organoids connect to host vessels following transplantation. Remarkably, MPCs also deliver Iba1\(^+\) cells that infiltrate the neural tissue in a microglia-like manner.}, language = {en} } @article{WoersdoerferErguen2023, author = {W{\"o}rsd{\"o}rfer, Philipp and Erg{\"u}n, S{\"u}leyman}, title = {"Organoids": insights from the first issues}, series = {Organoids}, volume = {2}, journal = {Organoids}, number = {2}, issn = {2674-1172}, doi = {10.3390/organoids2020006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313694}, pages = {79 -- 81}, year = {2023}, abstract = {No abstract available}, language = {en} } @article{WoersdoerferIAsahinaetal.2020, author = {W{\"o}rsd{\"o}rfer, Philipp and I, Takashi and Asahina, Izumi and Sumita, Yoshinori and Erg{\"u}n, S{\"u}leyman}, title = {Do not keep it simple: recent advances in the generation of complex organoids}, series = {Journal of Neural Transmission}, volume = {127}, journal = {Journal of Neural Transmission}, issn = {0300-9564}, doi = {10.1007/s00702-020-02198-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235628}, pages = {1569-1577}, year = {2020}, abstract = {3D cell culture models which closely resemble real human tissues are of high interest for disease modelling, drug screening as well as a deeper understanding of human developmental biology. Such structures are termed organoids. Within the last years, several human organoid models were described. These are usually stem cell derived, arise by self-organization, mimic mechanisms of normal tissue development, show typical organ morphogenesis and recapitulate at least some organ specific functions. Many tissues have been reproduced in vitro such as gut, liver, lung, kidney and brain. The resulting entities can be either derived from an adult stem cell population, or generated from pluripotent stem cells using a specific differentiation protocol. However, many organoid models only recapitulate the organs parenchyma but are devoid of stromal components such as blood vessels, connective tissue and inflammatory cells. Recent studies show that the incorporation of endothelial and mesenchymal cells into organoids improved their maturation and might be required to create fully functional micro-tissues, which will allow deeper insights into human embryogenesis as well as disease development and progression. In this review article, we will summarize and discuss recent works trying to incorporate stromal components into organoids, with a special focus on neural organoid models.}, language = {en} } @article{WuenschRiesHeinzelmannetal.2023, author = {W{\"u}nsch, Anna Chiara and Ries, Elena and Heinzelmann, Sina and Frabschka, Andrea and Wagner, Peter Christoph and Rauch, Theresa and Koderer, Corinna and El-Mesery, Mohamed and Volland, Julian Manuel and K{\"u}bler, Alexander Christian and Hartmann, Stefan and Seher, Axel}, title = {Metabolic silencing via methionine-based amino acid restriction in head and neck cancer}, series = {Current Issues in Molecular Biology}, volume = {45}, journal = {Current Issues in Molecular Biology}, number = {6}, issn = {1467-3045}, doi = {10.3390/cimb45060289}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319257}, pages = {4557 -- 4573}, year = {2023}, abstract = {In recent years, various forms of caloric restriction (CR) and amino acid or protein restriction (AAR or PR) have shown not only success in preventing age-associated diseases, such as type II diabetes and cardiovascular diseases, but also potential for cancer therapy. These strategies not only reprogram metabolism to low-energy metabolism (LEM), which is disadvantageous for neoplastic cells, but also significantly inhibit proliferation. Head and neck squamous cell carcinoma (HNSCC) is one of the most common tumour types, with over 600,000 new cases diagnosed annually worldwide. With a 5-year survival rate of approximately 55\%, the poor prognosis has not improved despite extensive research and new adjuvant therapies. Therefore, for the first time, we analysed the potential of methionine restriction (MetR) in selected HNSCC cell lines. We investigated the influence of MetR on cell proliferation and vitality, the compensation for MetR by homocysteine, the gene regulation of different amino acid transporters, and the influence of cisplatin on cell proliferation in different HNSCC cell lines.}, language = {en} } @phdthesis{WuertembergerPietsch2017, author = {W{\"u}rtemberger-Pietsch, Sabrina}, title = {Anionic and Neutral Lewis-Base Adducts of Diboron(4) Compounds}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-136321}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2017}, abstract = {Anionic Adducts Sp2-sp3 tetraalkoxy diboron compounds have gained attention due to the development of new, synthetically useful catalytic reactions either with or without transition-metals. Lewis-base adducts of the diboron(4) compounds were suggested as possible intermediates in Cu catalyzed borylation reactions some time ago. However, intermolecular adducts of tetraalkoxy diboron compounds have not been studied yet in great detail. In preliminary studies, we have synthesized a series of anionic sp2-sp3 adducts of B2pin2 with alkoxy-groups (L = [OMe]-, [OtBu]-), a phenoxy-group (L = [4-tBuC6H4O]-) and fluoride (L = [F]-, with [nBu4N]+ as the counter ion) as Lewis-bases. Neutral Adducts Since their isolation and characterization, applications of N-heterocyclic carbenes (NHCs) and related molecules, e.g., cyclic alkylaminocarbenes (CAACs) and acyclic diaminocarbenes (aDCs), have grown rapidly. Their use as ligands in homogeneous catalysis and directly in organocatalysis, including recently developed borylation reactions, is now well established. Recently, several examples of ring expansion reactions (RER) involving NHCs were reported to take place at elevated temperatures, involving Be, B, and Si. Furthermore, preliminary studies in the group of Marder et al. showed the presence of neutral sp2-sp3 diboron compounds with B2pin2 and the NHC Cy2Im. In this work, we focused on the synthesis and characterization of further neutral sp2-sp3 as well as sp3-sp3 diboron adducts with B2cat2 and B2neop2 and different NHCs. Whereas the mono-NHC adduct is stable for several hours at temperatures up to 60 °C, the bis-NHC adducts undergo thermally induced rearrangement to form the ring expanded products compound 26 and 27. B2neop2 is much more reactive than B2cat2 giving ring expanded product 29 at room temperature in quantitative yields, demonstrating that NHC ring expansion and B-B bond cleavage can be very facile processes. Whereas the mono-NHC adduct is stable for several hours at temperatures up to 60 °C, the bis-NHC adducts undergo thermally induced rearrangement to form the ring expanded products compound 26 and 27. B2neop2 is much more reactive than B2cat2 giving ring expanded product 29 at room temperature in quantitative yields, demonstrating that NHC ring expansion and B-B bond cleavage can be very facile processes.}, subject = {Addukt}, language = {en} } @article{WuerthnerMezaChinchaSchindleretal.2021, author = {W{\"u}rthner, Frank and Meza-Chincha, Ana-Lucia and Schindler, Dorothee and Natali, Mirco}, title = {Effects of Photosensitizers and Reaction Media on Light-Driven Water Oxidation with Trinuclear Ruthenium Macrocycles}, series = {ChemPhotoChem}, volume = {5}, journal = {ChemPhotoChem}, number = {2}, doi = {10.1002/cptc.202000133}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230116}, pages = {173-183}, year = {2021}, abstract = {Photocatalytic water oxidation is a promising process for the production of solar fuels and the elucidation of factors that influence this process is of high significance. Thus, we have studied in detail light-driven water oxidation with a trinuclear Ru(bda) (bda: 2,2'-bipyridine-6,6'-dicarboxylate) macrocycle MC3 and its highly water soluble derivative m-CH\(_2\)NMe\(_2\)-MC3 using a series of ruthenium tris(bipyridine) complexes as photosensitizers under varied reaction conditions. Our investigations showed that the catalytic activities of these Ru macrocycles are significantly affected by the choice of photosensitizer (PS) and reaction media, in addition to buffer concentration, light intensity and concentration of the sensitizer. Our steady-state and transient spectroscopic studies revealed that the photocatalytic performance of trinuclear Ru(bda) macrocycles is not limited by their intrinsic catalytic activities but rather by the efficiency of photogeneration of oxidant PS\(^+\) and its ability to act as an oxidizing agent to the catalysts as both are strongly dependent on the choice of photosensitizer and the amount of employed organic co-solvent.}, language = {en} } @article{WuerthnerNoll2021, author = {W{\"u}rthner, Frank and Noll, Niklas}, title = {A Calix[4]arene-Based Cyclic Dinuclear Ruthenium Complex for Light-Driven Catalytic Water Oxidation}, series = {Chemistry - A European Journal}, volume = {27}, journal = {Chemistry - A European Journal}, number = {1}, doi = {10.1002/chem.202004486}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230030}, pages = {444-450}, year = {2021}, abstract = {A cyclic dinuclear ruthenium(bda) (bda: 2,2'-bipyridine-6,6'-dicarboxylate) complex equipped with oligo(ethylene glycol)-functionalized axial calix[4]arene ligands has been synthesized for homogenous catalytic water oxidation. This novel Ru(bda) macrocycle showed significantly increased catalytic activity in chemical and photocatalytic water oxidation compared to the archetype mononuclear reference [Ru(bda)(pic)\(_2\)]. Kinetic investigations, including kinetic isotope effect studies, disclosed a unimolecular water nucleophilic attack mechanism of this novel dinuclear water oxidation catalyst (WOC) under the involvement of the second coordination sphere. Photocatalytic water oxidation with this cyclic dinuclear Ru complex using [Ru(bpy)\(_3\)]Cl\(_2\) as a standard photosensitizer revealed a turnover frequency of 15.5 s\(^{-1}\) and a turnover number of 460. This so far highest photocatalytic performance reported for a Ru(bda) complex underlines the potential of this water-soluble WOC for artificial photosynthesis.}, language = {en} } @phdthesis{XavierdeSouza2024, author = {Xavier de Souza, Aline}, title = {Ecophysiological adaptations of the cuticular water permeability within the Solanaceae family}, doi = {10.25972/OPUS-22539}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225395}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {The cuticle, a complex lipidic layer synthesized by epidermal cells, covers and protects primary organs of all land plants. Its main function is to avoid plant desiccation by limiting non-stomatal water loss. The cuticular properties vary widely among plant species. So far, most of the cuticle-related studies have focused on a limited number of species, and studies addressing phylogenetically related plant species are rare. Moreover, comparative studies among organs from the same plant species are still scarce. Thus, this study focus on organ-specificities of the cuticle within and between plant species of the Solanaceae family. Twenty-seven plant species of ten genera, including cultivated and non- cultivated species, were investigated to identify potential cuticular similarities. Structural, chemical and functional traits of fully expanded leaves, inflated fruiting calyces, and ripe fruits were analyzed. The surface morphology was investigated by scanning electron microscopy. Leaves were mainly amphistomatic and covered by an epicuticular wax film. The diversity and distribution of trichomes varied among species. Only the leaves of S. grandiflora were glabrous. Plant species of the Leptostemonum subgenus had numerous prickles and non-glandular stellate trichomes. Fruits were stomata-free, except for S. muricatum, and a wax film covered their surface. Last, lenticel- like structures and remaining scars of broken trichomes were found on the surface of some Solanum fruits. Cuticular water permeability was used as indicators of the cuticular transpiration barrier efficiency. The water permeability differed among plant species, organs and fruit types with values ranging up to one hundred-fold. The minimum leaf conductance ranged from 0.35 × 10-5 m s-1 in S. grandiflora to 31.54 × 10-5 m s-1 in S. muricatum. Cuticular permeability of fruits ranged from 0.64 × 10-5 m s-1 in S. dulcamara (fleshy berry) to 34.98 × 10-5 m s-1 in N. tabacum (capsule). Generally, the cuticular water loss of dry fruits was about to 5-fold higher than that of fleshy fruits. Interestingly, comparisons between cultivated and non-cultivated species showed that wild species have the most efficient cuticular transpiration barrier in leaves and fruits. The average permeability of leaves and fruits of wild plant species was up to three-fold lower in comparison to the cultivated ones. Moreover, ripe fruits of P. ixocarpa and P. peruviana showed two-times lower cuticular transpiration when enclosed by the inflated fruiting calyx. The cuticular chemical composition was examined using gas chromatography. Very-long-chain aliphatic compounds primarily composed the cuticular waxes, being mostly dominated by n- alkanes (up to 80\% of the total wax load). Primary alkanols, alkanoic acids, alkyl esters and branched iso- and anteiso-alkanes were also frequently found. Although in minor amounts, sterols, pentacyclic triterpenoids, phenylmethyl esters, coumaric acid esters, and tocopherols were identified in the cuticular waxes. Cuticular wax coverages highly varied in solanaceous (62- fold variation). The cuticular wax load of fruits ranged from 0.55 μg cm-2 (Nicandra physalodes) to 33.99 μg cm-2 (S. pennellii), whereas the wax amount of leaves varied from 0.90 μg cm-2 (N. physalodes) to 28.42 μg cm-2 (S. burchellii). Finally, the wax load of inflated fruiting calyces ranged from 0.56 μg cm-2 in P. peruviana to 2.00 μg cm-2 in N. physalodes. For the first time, a comparative study on the efficiency of the cuticular transpiration barrier in different plant organs of closely related plant species was conducted. Altogether, the cuticular chemical variability found in solanaceous species highlight species-, and organ-specific wax biosynthesis. These chemical variabilities might relate to the waterproofing properties of the plant cuticle, thereby influencing leaf and fruit performances. Additionally, the high cuticular water permeabilities of cultivated plant species suggest a potential existence of a trade-off between fruit organoleptic properties and the efficiency of the cuticular transpiration barrier. Last, the high cuticular water loss of the solanaceous dry fruits might be a physiological adaptation favouring seed dispersion.}, subject = {Kutikula}, language = {en} } @phdthesis{Xian2014, author = {Xian, Yibo}, title = {Identification of essential genes and novel virulence factors of Neisseria gonorrhoeae by transposon mutagenesis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-102659}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2014}, abstract = {Neisseria gonorrhoeae is a human-specific pathogen that causes gonorrhea. It is defined as a super bacterium by the WHO due to the emergence of gonococci that are resistant to a variety of antibiotics and a rapidly increasing infection incidence. Genome-wide investigation of neisserial gene essentiality and novel virulence factors is urgently required in order to identify new targets for anti-neisserial therapeutics. To identify essential genes and new virulence factors, a high-density mutant library in N. gonorrhoeae MS11 was generated by in vitro transposon mutagenesis. The transposon library harbors more than 100,000 individual mutants, a density that is unprecedented in gonococcal research. Essential genes in N. gonorrhoeae were determined by enumerating frequencies of transposon insertion sites (TIS) with Illumina deep sequencing (Tn-seq). Tn-seq indicated an average distance between adjacent TIS of 25 bp. Statistical analysis unequivocally demonstrated 781 genes that were significantly depleted in TIS and thus are essential for Neisseria survival. A subset of the genes was experimentally verified to comprise essential genes and thus support the outcome of the study. The hereby identified candidate essential genes thus may constitute excellent targets for the development of new antibiotics or vaccines. In a second study, the transposon mutant library was applied in a genome-scale "negative-selection strategy" to identify genes that are involved in low phosphate-dependent invasion (LPDI). LPDI is dependent on the Neisseria porin subtype PorBIA which acts as an epithelial cell invasin in absence of phosphate and is associated with severe pathogenicity in disseminated gonococcal infections (DGI). Tn-seq demonstrated 98 genes, which were involved in adherence to host cells and 43 genes involved in host cell invasion. E.g. the hypothetical protein NGFG_00506, an ABC transporter ATP-binding protein NGFG_01643, as well as NGFG_04218 encoding a homolog of mafI in N. gonorrhoeae FA1090 were experimentally verified as new invasive factors in LPDI. NGFG_01605, a predicted protease, was identified to be a common factor involved in PorBIA, Opa50 and Opa57-mediated neisserial engulfment by the epithelial cells. Thus, this first systematic Tn-seq application in N. gonorrhoeae identified a set of previously unknown N. gonorrhoeae invasive factors which demonstrate molecular mechanisms of DGI.}, subject = {Neisseria gonorrhoeae}, language = {en} } @phdthesis{Xiang2006, author = {Xiang, Chaomei}, title = {The role of B-RAF in embryonic development of mouse forebrain}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-18326}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Die Familie der RAF-Kinasen umfasst drei Mitglieder, A-RAF, B-RAF und C-RAF. Nur f{\"u}r die B-RAF-Isoform wurde eine wichtige Funktion f{\"u}r die Entwicklung des Zentralen Nervensystems (ZNS) gefunden. Das Fehlen von B-RAF f{\"u}hrt bei neu generierten embryonalen Neuronen zum Zelltod, weil sie in vitro nicht auf {\"u}berlebensfaktoren reagieren k{\"o}nnen. Bei einer zweiten Zelllinie, die durch die Abwesenheit von B-RAF beeintr{\"a}chtigt ist, handelt es sich um endotheliale Zellen. Ihr Zelltod f{\"u}hrt zu inneren Blutungen und zu Letalit{\"a}t von B-RAF-/--M{\"a}usen zwischen Tag 10.5 (E10.5) und 12.5 (E12.5) der Embryonalentwicklung. Dies verhinderte bisher weitere Untersuchungen der neuralen B-RAF-Funktion bei sp{\"a}teren Stadien. Im Gegensatz zu B-RAF-/--M{\"a}usen {\"u}berleben B-RAFKIN/KIN-M{\"a}use die Mitte der Embryonalentwicklung, da ihre Endothelzellen vor Apoptose gesch{\"a}tzt sind. Diese Tiere besitzen kein B-RAF, stattdessen wird im B-RAF-Locus ein chim{\"a}res Protein exprimiert, das den N-Terminus von B-RAF sowie alle Dom{\"a}nen von A-RAF umfasst. Der Schutz vor abnormaler neuraler Apoptose im Vorderhirn macht diese Tiere zu einem potentiellen Modell zur Untersuchung der Proliferations- und Differenzierungsfunktion von B-RAF, die die Kinase neben der {\"U}berlebensfunktion in der ZNS-Entwicklung aus{\"u}bt. Die detaillierte Untersuchung der B-RAFKIN/KIN-Tiere konzentrierte sich auf die Entwicklung der Hirnrinde. Augenscheinlich waren kortikale Defekte im B-RAFKIN/KIN Vorderhirn: Der Verlust von B-RAF f{\"u}hrte zu einer starken Reduzierung von Brn-2 exprimierenden pyramidalen Projektions-Neuronen begleitet von einer St{\"o}rung der Dendritenbildung mit weniger und d{\"u}nneren Dendriten in diesen oberen Schichten. Weitere Untersuchungen mit BrdU-Markierungsexperimenten zeigten in der ventrikul{\"a}ren Schicht reduzierte Zellproliferation f{\"u}r E14.5-E16.5 der Mutantenembryonen und ein Migrationsdefizit der sp{\"a}tgebideten kortikalen Neuronen. W{\"a}hrend der Proliferationsdefekt der Hirnrinden-Vorl{\"a}uferzellen mit einer reduzierten ERK-Aktivierung einherging, bleibt der Mechanismus der gest{\"o}rten neuralen Migration zu erkl{\"a}ren. Unsere Hypothese ist, dass die subzellul{\"a}re Lokalisation von Phospho-ERK in den wandernden Hirnrinden-Neuronen der B-RAFKIN/KIN-M{\"a}use ver{\"a}ndert sein k{\"o}nnte. Zur Best{\"a}igung der in vivo-Funktion von B-RAF und weiteren Studien zu ihrer unbekannten Rolle in der embryonalen Neurogenese sowie anderen Morphogenesen w{\"a}re die konditionale B-RAF Inaktivierung erforderlich. Durch die Deletion des genetischen Materials bzw. die Inaktivierung der Genfunktion in ausgew{\"i}?'½hlten Zellen zu einem bestimmten Zeitpunkt ließen sich die Embryo-Letalit{\"a}t sowie unerw{\"u}nschte pleiotrope Nebeneffekte vermeiden und akkumulierende, kompensierende Entwicklungsver{\"a}nderungen von Beginn an ausschließen. Um die Cre Rekombinase-Methode einsetzen zu k{\"o}nnen, wurden floxed B-RAF embryonale Stammzell (ES)-Zelllinien generiert. Außerdem wurde ein auf dem Tetrazyklin Operator basierendes Schaltallel in den B-RAF Genort von embryonalen Stammzellen integriert, so dass die B-RAF Expression konditional und reversibel durch die Zugabe von Doxyzyklin angeschaltet werden konnte. Bisher wurden hochgradige chim{\"a}re M{\"a}use nach Blastozysten-Injektion geboren. Die Keimbahn{\"u}bertragung dieser chim{\"a}ren M{\"a}use wird momentan untersucht. Wenn beide konditionale Mauslinien bereit sind, k{\"i}?'½nnte die Entwicklung ihres Zentralnervensystems untersucht werden, um die Rolle von B-RAF in der Entwicklung des Nervensystems herauszufinden.}, subject = {Maus}, language = {en} } @phdthesis{Xiao2023, author = {Xiao, Yin}, title = {Lack of NFATc1 SUMOylation prevents autoimmunity and alloreactivity}, doi = {10.25972/OPUS-32105}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-321054}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {SUMOylation, as a post-translational modification, plays a crucial role in several biological processes. Small ubiquitin-like modifier (SUMO) proteins can be reversibly linked to the lysine residues located within specific motifs on numerous target proteins, leading to the change of stability, localization, activity of target proteins, mostly by promoting or interfering with the interaction with other molecules. Consequently, it can regulate gene transcription, migration, cell cycle progression, cellular responses to stress, and tumorigenesis. NFATc1 belongs to the Nuclear Factor of Activated T-cells (NFAT) transcription factor family, which is dephosphorylated and translocates to the nucleus upon cell stimulation, which provokes Ca2+ signalling. NFAT plays a crucial role in the development and function of the immune system. NFATc1 has three SUMOylation sites at the position of aa 349, 702, and 914. In our previous study, we demonstrated that point mutations performed on the SUMOylation sites on all three or only at the lysine residues K702 and K914 lead to enhanced expression of IL-2 in vitro. To evaluate the function of SUMOylation of NFATc1 on T cell-mediated immunity in vivo, we not only generated a transgenic mouse strain (NFATc1/ΔS+ mouse) by point mutations from Lysine to Arginine on the two SUMOylation sites within exon 10 of Nfatc1 to prevent their SUMOylation, but in combination created another mouse strain (NFATc1/ΔBC+ mouse) that is completely Nfatc1 exon 10-ablated by using the LoxP/Cre system. In NFATc1/ΔS+ T cells, we observed enhanced IL-2 production and less IL-17A and IFN-γ expression. In line with exon 10 bearing the relevant SUMO sites, NFATc1/ΔBC+ CD4+ T cells behaved similarly as NFATc1/ΔS+ ones. The mechanism is that elevated IL-2 secretion can counteract the expression of IL-17A and IFN-γ via STAT5 and Blimp-1 induction. Afterwards, Blimp-1 suppressed IL-2 itself as well as Bcl2A1. Next, we performed two disease models with our NFATc1/ΔS+ mice. In a major mismatch model for acute graft-versus-host disease, we found that the mice transplanted with NFATc1/ΔS+ CD3+ T cells developed less severe disease, and T cells proliferated less due to increased Tregs. Moreover, when transferring 2D2.NFATc1/ΔS+ Th1 plus Th17 cells to Rag1-/- mice to induce experimental autoimmune encephalitis, we also observed ameliorated disease compared to animals with transferred WT T cells as well as increased Tregs. Taking all data together, the deficiency in SUMOylation of NFATc1 leads to an elevated IL-2 secretion in T cells and subsequent activation of STAT5, which competes with STAT3 to inhibit IL-17A production and promotes Treg expansion, as well as to an enforcement of Blimp-1 expression, which suppresses IFN-γ and IL-2 expression. Consequently and despite a short phase of enhanced IL-2 secretion, the deficiency of SUMOylation on NFATc1 can protect from autoreactive and alloreactive diseases. Moreover, to further understand the function of SUMOylation of NFATc1 in humans, we started by establishing an in vitro 3D culture system for tonsil organoids, which was successful in the presence of feeder cells, along with IL-4 and IL-7 cytokines. To confirm that our 3D tonsil organoids can respond to real antigens, we used CMV peptides and peptides of spike proteins from Covid-19 as real antigens, and co-cultured with tonsil organoids, which indeed can generate memory cells and plasmablasts. In the end, we also compared 3D to 2D cultures. Although the total numbers of all B cell subsets were much less in 3D culture than that in 2D culture, still, it indicates that this in-vitro culture system has its limitation, while being usable to produce the similar results as 2D did. Therefore, this 3D culture system can be used as a platform to investigate NFATc1/ΔS+ or NFATc1/ΔBC+ TFH and TFR cells in the dynamic of human GC responses.}, language = {en} } @phdthesis{Xiao2004, author = {Xiao, Zheng}, title = {Blimp-1 Regulates Terminal Differentiation of T Cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-10530}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2004}, abstract = {The transcriptional repressor-Blimp-1 terminates differentiation of B lymphocytes as well as myeloid cells. Our data show that Blimp-1 is highly expressed in freshly isolated murine primary T lymphocytes, particularly its minor splice variant. Ectopic expression of Blimp-1 by retroviral transduction neither dramatically altered secretion of IFN-{\~a} or IL-4 nor did it induce the ability to suppress as regulatory T cells. However, induction of Blimp-1 resulted in not only a significant reduction in the production of IL-2 but also an inability to proliferate as well as in the reduced viability. These results demonstrate that Blimp-1 might mark end stages of lineage differentiation in T cells.}, language = {en} } @article{XiuGeigerKlaver2015, author = {Xiu, Daiming and Geiger, Maximilian J. and Klaver, Peter}, title = {Emotional face expression modulates occipital-frontal effective connectivity during memory formation in a bottom-up fashion}, series = {Frontiers in Behavioral Neuroscience}, volume = {9}, journal = {Frontiers in Behavioral Neuroscience}, number = {90}, doi = {10.3389/fnbeh.2015.00090}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143211}, year = {2015}, abstract = {This study investigated the role of bottom-up and top-down neural mechanisms in the processing of emotional face expression during memory formation. Functional brain imaging data was acquired during incidental learning of positive ("happy"), neutral and negative ("angry" or "fearful") faces. Dynamic Causal Modeling (DCM) was applied on the functional magnetic resonance imaging (fMRI) data to characterize effective connectivity within a brain network involving face perception (inferior occipital gyrus and fusiform gyrus) and successful memory formation related areas (hippocampus, superior parietal lobule, amygdala, and orbitofrontal cortex). The bottom-up models assumed processing of emotional face expression along feed forward pathways to the orbitofrontal cortex. The top-down models assumed that the orbitofrontal cortex processed emotional valence and mediated connections to the hippocampus. A subsequent recognition memory test showed an effect of negative emotion on the response bias, but not on memory performance. Our DCM findings showed that the bottom-up model family of effective connectivity best explained the data across all subjects and specified that emotion affected most bottom-up connections to the orbitofrontal cortex, especially from the occipital visual cortex and superior parietal lobule. Of those pathways to the orbitofrontal cortex the connection from the inferior occipital gyrus correlated with memory performance independently of valence. We suggest that bottom-up neural mechanisms support effects of emotional face expression and memory formation in a parallel and partially overlapping fashion.}, language = {en} } @phdthesis{Xu2014, author = {Xu, Jiajia}, title = {A high-complexity lentiviral shRNA screen identifies synthetic lethal interactions with deregulated N-Myc in neuroblastoma cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-103157}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2014}, abstract = {In contrast to c-Myc, a deregulated expression of the MYCN gene is restricted to human neuroendocrine tumours. In most cases, the excessive activity of N-Myc results from a MYCN amplification. In neuroblastoma, amplification of MYCN is a predictor of poor prognosis and resistance to therapy. The inability to target the N-Myc protein directly necessitates the search for alternative targets. This project aimed at identifying genes specifically required for growth and survival of cells that express high levels of N-Myc using high-throughput shRNA screening combined with next generation sequencing. The identification and analysis of these genes will shed light on functional interaction partners of N-Myc. We screened a shRNA library containing 18,327 shRNAs and identified 148 shRNAs, which were selectively depleted in the presence of active N-Myc. In addition, shRNAs targeting genes that are involved in p53 and ARF turnover and apoptosis were depleted in the cell population during the screen. These processes are known to affect N-Myc-mediated apoptosis. Consequently, these results biologically validated the screen. The 148 shRNAs that showed a significant synthetic lethal interaction with high levels of N-Myc expression were further analysed using the bioinformatics program DAVID. We found an enrichment of shRNAs that target genes involved in specific biological processes. For example, we validated synthetic lethal interactions for genes such as, THOC1, NUP153 and LARP7, which play an important role in the process of RNA polymerase II-mediated transcription elongation. We also validated genes that are involved in the neddylation pathway. In the screen we identified Cullin 3, which is a component of the BTB-CUL3-Rbx1 ubiquitin ligase that is involved in the turnover of Cyclin E. Depletion of cullin 3 and activation of N-Myc was found to synergistically increase Cyclin E expression to supraphysiological levels, inducing S-phase arrest and a strong DNA damage response. Together with results from a proteomics analysis of N-Myc associated proteins, our results lead us to the following hypothesis: In a neuroblastoma cell, the high levels of N-Myc result in a conflict between RNA polymerase II and the replication machinery during S-phase. The newly identified interaction partners of N- Myc are required to solve this conflict. Consequently, loss of the interaction leads to a massive DNA damage and the induction of apoptosis. In addition, inhibition or depletion of the essential components of the neddylation pathway also results in an unresolvable problem during S-phase.}, subject = {Neuroblastom}, language = {en} } @article{XuFahmyGarciaWesdorpetal.2023, author = {Xu, Jietao and Fahmy-Garcia, Shorouk and Wesdorp, Marinus A. and Kops, Nicole and Forte, Lucia and De Luca, Claudio and Misciagna, Massimiliano Maraglino and Dolcini, Laura and Filardo, Giuseppe and Labbert{\´e}, Margot and Vanc{\´i}kov{\´a}, Karin and Kok, Joeri and van Rietbergen, Bert and Nickel, Joachim and Farrell, Eric and Brama, Pieter A. J. and van Osch, Gerjo J. V. M.}, title = {Effectiveness of BMP-2 and PDGF-BB adsorption onto a collagen/collagen-magnesium-hydroxyapatite scaffold in weight-bearing and non-weight-bearing osteochondral defect bone repair: in vitro, ex vivo and in vivo evaluation}, series = {Journal of Functional Biomaterials}, volume = {14}, journal = {Journal of Functional Biomaterials}, number = {2}, issn = {2079-4983}, doi = {10.3390/jfb14020111}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304019}, year = {2023}, abstract = {Despite promising clinical results in osteochondral defect repair, a recently developed bi-layered collagen/collagen-magnesium-hydroxyapatite scaffold has demonstrated less optimal subchondral bone repair. This study aimed to improve the bone repair potential of this scaffold by adsorbing bone morphogenetic protein 2 (BMP-2) and/or platelet-derived growth factor-BB (PDGF-BB) onto said scaffold. The in vitro release kinetics of BMP-2/PDGF-BB demonstrated that PDGF-BB was burst released from the collagen-only layer, whereas BMP-2 was largely retained in both layers. Cell ingrowth was enhanced by BMP-2/PDFG-BB in a bovine osteochondral defect ex vivo model. In an in vivo semi-orthotopic athymic mouse model, adding BMP-2 or PDGF-BB increased tissue repair after four weeks. After eight weeks, most defects were filled with bone tissue. To further investigate the promising effect of BMP-2, a caprine bilateral stifle osteochondral defect model was used where defects were created in weight-bearing femoral condyle and non-weight-bearing trochlear groove locations. After six months, the adsorption of BMP-2 resulted in significantly less bone repair compared with scaffold-only in the femoral condyle defects and a trend to more bone repair in the trochlear groove. Overall, the adsorption of BMP-2 onto a Col/Col-Mg-HAp scaffold reduced bone formation in weight-bearing osteochondral defects, but not in non-weight-bearing osteochondral defects.}, language = {en} } @article{XuNaeveriFrerichsetal.1993, author = {Xu, K. and N{\"a}veri, L. and Frerichs, K. and Hallenbeck, J. M. and Feuerstein, G. and Davis, J. N. and Sir{\´e}n, Anna-Leena}, title = {Extracellular catecholamine levels in rat hippocampus after a selective alpha2-adrenoceptor antagonist or a selective dopamnie uptake inhibitor: Evidence for dopamine release from local dopaminergic nerve terminals}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62997}, year = {1993}, abstract = {The effect of 6-chloro-2,3,4,5-tetrahydro-3-methyi-1-H-3-benzazepine (SKF 86466), a selectlve nonimldazoline alpha-2 adrenoceptor antagonlst, on hippocampal re1ease of norepinephrine and dopamlne in conscious rats was lnvestigated by /n vlvo mlcrodialysis and high-pressure liquid chromatography. Additionally, extracellular concentrations of hippocampal dopamine (DA) and norepinephrtne (NE), durtng Infusion of selective monoamine uptake Inhibitors, were determined in freely moving rats. The basal concentration of NE in the dialysate was 4.9 ± 0.3 pg/20 pl. lntravenous admlnistratlon of 5 or 10 mgJkg of SKF 86466 was associated wlth a transierlt inc:rease (30 min) of 2-fold (12 ± 1 pg/20 ,d; p < .05) and 8-fold (39 ± 3 pg/20 pl; p < .05), respectlvely, in dlalysate NE, whereas a 1-mgfkg dose had no effect. DA was not detected in basal dlalysates, but after the adminlstratlon of 5 or 10 mgJkg of SKF 86466, 3.9 ± 0.4 and 6.4 ± 0.6 pg/20 pl, respectlvely, was present in the dialysates. The rnaxlmum increase in dialysate DA was reached 60 to 90 min after SKF 86466. The DA was not derived from plasma because plasma NE was elevated after the 5 mgJkg dose of SKF 86466 whereas no plasma DA was detected. ln order to determlne whether DA was present in noradrenergic nerve termlnals, the dopamine ß-hydroxylase Inhibitor SKF 1 02698 was administered (50 mgJkg i.p.). The Inhibitor decreased dialysate NE but DA was stin not detected in the dialysate. When SKF 86466 (5 mgJkg t.v.) was adminlstered 4 hr after SKF 102698, DA appeared in the dialysate but there was no lncrease in dialysate NE. Administration through the dialysis probe of the DA uptake Inhibitor, GBR-12909 (0.1 and 1 pM), dose-dependently lnaeased DA Ieveis to 5.7 ± 1.2 and 9.6 ± 2.8 pg/20 pl, respectively. GBR-12909 had no effect on hippocampal NE. Desipramine (5 and 10 pM) lncreased dose-dependently dialysate NE and lncreased DA concentrations to detectable Ieveis (2.7 ± 0.5 and 3.5 ± 0.7 pg/20 ,d, respectively). These results suggest that the a/pha-2 adrenoceptors modulate both NE and DA release in the rat hlppocampus and that DA detected in the hlppocampal dialysate might be released from dopaminergic neurons.}, subject = {Neurobiologie}, language = {en} } @article{XuHeKaiseretal.2016, author = {Xu, Li and He, Jianzheng and Kaiser, Andrea and Gr{\"a}ber, Nikolas and Schl{\"a}ger, Laura and Ritze, Yvonne and Scholz, Henrike}, title = {A Single Pair of Serotonergic Neurons Counteracts Serotonergic Inhibition of Ethanol Attraction in Drosophila}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {12}, doi = {10.1371/journal.pone.0167518}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166762}, pages = {e0167518}, year = {2016}, abstract = {Attraction to ethanol is common in both flies and humans, but the neuromodulatory mechanisms underlying this innate attraction are not well understood. Here, we dissect the function of the key regulator of serotonin signaling—the serotonin transporter-in innate olfactory attraction to ethanol in Drosophila melanogaster. We generated a mutated version of the serotonin transporter that prolongs serotonin signaling in the synaptic cleft and is targeted via the Gal4 system to different sets of serotonergic neurons. We identified four serotonergic neurons that inhibit the olfactory attraction to ethanol and two additional neurons that counteract this inhibition by strengthening olfactory information. Our results reveal that compensation can occur on the circuit level and that serotonin has a bidirectional function in modulating the innate attraction to ethanol. Given the evolutionarily conserved nature of the serotonin transporter and serotonin, the bidirectional serotonergic mechanisms delineate a basic principle for how random behavior is switched into targeted approach behavior.}, language = {en} } @article{XuShengGreineretal.1994, author = {Xu, Shanjia and Sheng, Xinqing and Greiner, P. and Becker, Charles R. and Geick, R.}, title = {High-order finite-element analysis of scattering properties of II-VI semiconductor materials}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86283}, year = {1994}, abstract = {The sattering characteristics ot the n-VI semiconductors were analyzed by a method which combines the second-order finite-element method with the rigorous mode matching procedure. The method avolds the difficulty of solving the complex transcendental equation introduced in the multimode network method and calculates all the eigenvalues and eigenfunctions simultaneously which are needed for the mode matching treatment in the longitudinal direction. As a result, the whole solution procedure is significantly simplified. A comparison is given between the experimental data and the calculated results obtained with this analysis and tbe network method. Very good agreement has been achieved, the accuracy and efficiency of the present method are thus verified.}, subject = {Halbleiter}, language = {en} } @phdthesis{Xu2022, author = {Xu, Wenshan}, title = {Regulation of the DNA Damage Response by the Ubiquitin System}, doi = {10.25972/OPUS-16006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-160064}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {DNA damage occurs frequently during normal cellular progresses or by environmental factors. To preserve the genome integrity, DNA damage response (DDR) has evolved to repair DNA and the non-properly repaired DNA induces human diseases like immune deficiency and cancer. Since a large number of proteins involved in DDR are enzymes of ubiquitin system, it is critical to investigate how the ubiquitin system regulates cellular response to DNA damage. Hereby, we reveal a novel mechanism for DDR regulation via activation of SCF ubiquitin ligase upon DNA damage. As an essential step for DNA damage-induced inhibition of DNA replication, Cdc25A degradation by the E3 ligase β-TrCP upon DNA damage requires the deubiquitinase Usp28. Usp28 deubiquitinates β-TrCP in response to DNA damage, thereby promotes its dimerization, which is required for its activity in substrate ubiquitination and degradation. Particularly, ubiquitination at a specific lysine on β-TrCP suppresses dimerization. The key mediator protein of DDR, 53BP1, forms oligomers and associates with β-TrCP to inhibit its activity in unstressed cells. Upon DNA damage, 53BP1 is degraded in the nucleoplasm, which requires oligomerization and is promoted by Usp28 in a β-TrCP-dependent manner. Consequently, 53BP1 destruction releases and activates β-TrCP during DNA damage response. Moreover, 53BP1 deletion and DNA damage promote β-TrCP dimerization and recruitment to chromatin sites that locate in the vicinity of putative replication origins. Subsequently, the chromatin-associated Cdc25A is degraded by β-TrCP at the origins. The stimulation of β-TrCP binding to the origins upon DNA damage is accompanied by unloading of Cdc45, a crucial component of pre-initiation complexes for replication. Loading of Cdc45 to origins is a key Cdk2-dependent step for DNA replication initiation, indicating that localized Cdc25A degradation by β-TrCP at origins inactivates Cdk2, thereby inhibits the initiation of DNA replication. Collectively, this study suggests a novel mechanism for the regulation of DNA replication upon DNA damage, which involves 53BP1- and Usp28-dependent activation of the SCF(β-TrCP) ligase in Cdc25A degradation.}, subject = {DNS-Sch{\"a}digung}, language = {en} } @phdthesis{Xu2014, author = {Xu, Zhihao}, title = {Cooperative Formation Controller Design for Time-Delay and Optimality Problems}, isbn = {978-3-923959-96-9}, doi = {10.25972/OPUS-10555}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-105555}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2014}, abstract = {This dissertation presents controller design methodologies for a formation of cooperative mobile robots to perform trajectory tracking and convoy protection tasks. Two major problems related to multi-agent formation control are addressed, namely the time-delay and optimality problems. For the task of trajectory tracking, a leader-follower based system structure is adopted for the controller design, where the selection criteria for controller parameters are derived through analyses of characteristic polynomials. The resulting parameters ensure the stability of the system and overcome the steady-state error as well as the oscillation behavior under time-delay effect. In the convoy protection scenario, a decentralized coordination strategy for balanced deployment of mobile robots is first proposed. Based on this coordination scheme, optimal controller parameters are generated in both centralized and decentralized fashion to achieve dynamic convoy protection in a unified framework, where distributed optimization technique is applied in the decentralized strategy. This unified framework takes into account the motion of the target to be protected, and the desired system performance, for instance, minimal energy to spend, equal inter-vehicle distance to keep, etc. Both trajectory tracking and convoy protection tasks are demonstrated through simulations and real-world hardware experiments based on the robotic equipment at Department of Computer Science VII, University of W{\"u}rzburg.}, subject = {Optimalwertregelung}, language = {en} } @phdthesis{Yadav2016, author = {Yadav, Preeti}, title = {Studying Neuronal Cytoskeleton Defects and Synaptic Defects in Mouse Model of Amyotrophic Lateral Sclerosis and Spinal Muscular Atrophy}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138093}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2016}, abstract = {Amyotrophic lateral sclerosis and spinal muscular atrophy are the two most common motoneuron diseases. Both are characterized by destabilization of axon terminals, axon degeneration and alterations in neuronal cytoskeleton. Accumulation of neurofilaments has been observed in several neurodegenerative diseases but the mechanisms how elevated neurofilament levels destabilize axons are unknown so far. Here, I show that increased neurofilament expression in motor nerves of pmn mutant mice causes disturbed microtubule dynamics. Depletion of neurofilament by Nefl knockout increases the number and regrowth of microtubules in pmn mutant motoneurons and restores axon elongation. This effect is mediated by interaction of neurofilament with the stathmin complex. Depletion of neurofilament increases stathmin-Stat3 interaction and stabilizes the microtubules. Consequently, the axonal maintenance is improved and the pmn mutant mice survive longer. We propose that this mechanism could also be relevant for other neurodegenerative diseases in which neurofilament accumulation is a prominent feature. Next, using Smn-/-;SMN2 mouse as a model, the molecular mechanism behind synapse loss in SMA is studied. SMA is characterized by degeneration of lower α-motoneurons in spinal cord; however, how reduction of ubiquitously expressed SMN leads to MN-specific degeneration remains unclear. SMN is involved in pre-mRNA splicing (Pellizzoni, Kataoka et al. 1998) and its deficiency in SMA affects the splicing machinery. Neuromuscular junction denervation precedes neurodegeneration in SMA. However, there is no evidence of a link between aberrant splicing of transcripts downstream of Smn and reduced presynaptic axon excitability observed in SMA. In this study, we observed that expression and splicing of Nrxn2, that encodes a presynaptic protein is affected in the SMA mouse and that Nrxn2 could be a candidate that relates aberrant splicing to synaptic motoneuron defects in SMA.}, subject = {Neurofilament}, language = {en} } @article{YadavSelvarajBenderetal.2016, author = {Yadav, Preeti and Selvaraj, Bhuvaneish T. and Bender, Florian L. P. and Behringer, Marcus and Moradi, Mehri and Sivadasan, Rajeeve and Dombert, Benjamin and Blum, Robert and Asan, Esther and Sauer, Markus and Julien, Jean-Pierre and Sendtner, Michael}, title = {Neurofilament depletion improves microtubule dynamics via modulation of Stat3/stathmin signaling}, series = {Acta Neuropathologica}, volume = {132}, journal = {Acta Neuropathologica}, number = {1}, doi = {10.1007/s00401-016-1564-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188234}, pages = {93-110}, year = {2016}, abstract = {In neurons, microtubules form a dense array within axons, and the stability and function of this microtubule network is modulated by neurofilaments. Accumulation of neurofilaments has been observed in several forms of neurodegenerative diseases, but the mechanisms how elevated neurofilament levels destabilize axons are unknown so far. Here, we show that increased neurofilament expression in motor nerves of pmn mutant mice, a model of motoneuron disease, causes disturbed microtubule dynamics. The disease is caused by a point mutation in the tubulin-specific chaperone E (Tbce) gene, leading to an exchange of the most C-terminal amino acid tryptophan to glycine. As a consequence, the TBCE protein becomes instable which then results in destabilization of axonal microtubules and defects in axonal transport, in particular in motoneurons. Depletion of neurofilament increases the number and regrowth of microtubules in pmn mutant motoneurons and restores axon elongation. This effect is mediated by interaction of neurofilament with the stathmin complex. Accumulating neurofilaments associate with stathmin in axons of pmn mutant motoneurons. Depletion of neurofilament by Nefl knockout increases Stat3-stathmin interaction and stabilizes the microtubules in pmn mutant motoneurons. Consequently, counteracting enhanced neurofilament expression improves axonal maintenance and prolongs survival of pmn mutant mice. We propose that this mechanism could also be relevant for other neurodegenerative diseases in which neurofilament accumulation and loss of microtubules are prominent features.}, language = {en} } @article{YamakawaFukushimaItohetal.2012, author = {Yamakawa, Hisanori and Fukushima, Yoshimasa and Itoh, Shigeru and Heber, Ulrich}, title = {Three different mechanisms of energy dissipation of a desiccation-tolerant moss serve one common purpose: to protect reaction centres against photo-oxidation}, series = {Journal of Experimental Botany}, volume = {63}, journal = {Journal of Experimental Botany}, number = {10}, doi = {10.1093/jxb/ers062}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126897}, pages = {3765-3775}, year = {2012}, abstract = {Three different types of non-photochemical de-excitation of absorbed light energy protect photosystem II of the sun- and desiccation-tolerant moss Rhytidium rugosum against photo-oxidation. The first mechanism, which is light-induced in hydrated thalli, is sensitive to inhibition by dithiothreitol. It is controlled by the protonation of a thylakoid protein. Other mechanisms are activated by desiccation. One of them permits exciton migration towards a far-red band in the antenna pigments where fast thermal deactivation takes place. This mechanism appears to be similar to a mechanism detected before in desiccated lichens. A third mechanism is based on the reversible photo-accumulation of a radical that acts as a quencher of excitation energy in reaction centres of photosystem II. On the basis of absorption changes around 800 nm, the quencher is suggested to be an oxidized chlorophyll. The data show that desiccated moss is better protected against photo-oxidative damage than hydrated moss. Slow drying of moss thalli in the light increases photo-protection more than slow drying in darkness.}, language = {en} } @article{YanHongChenetal.2013, author = {Yan, Yan and Hong, Ni and Chen, Tiansheng and Li, Mingyou and Wang, Tiansu and Guan, Guijun and Qiao, Yongkang and Chen, Songlin and Schartl, Manfred and Li, Chang-Ming and Hong, Yunhan}, title = {p53 Gene Targeting by Homologous Recombination in Fish ES Cells}, series = {PLoS One}, volume = {8}, journal = {PLoS One}, number = {3}, doi = {10.1371/journal.pone.0059400}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133416}, pages = {e59400}, year = {2013}, abstract = {Background: Gene targeting (GT) provides a powerful tool for the generation of precise genetic alterations in embryonic stem (ES) cells to elucidate gene function and create animal models for human diseases. This technology has, however, been limited to mouse and rat. We have previously established ES cell lines and procedures for gene transfer and selection for homologous recombination (HR) events in the fish medaka (Oryzias latipes). Methodology and Principal Findings: Here we report HR-mediated GT in this organism. We designed a GT vector to disrupt the tumor suppressor gene p53 (also known as tp53). We show that all the three medaka ES cell lines, MES1 similar to MES3, are highly proficient for HR, as they produced detectable HR without drug selection. Furthermore, the positive-negative selection (PNS) procedure enhanced HR by similar to 12 folds. Out of 39 PNS-resistant colonies analyzed, 19 (48.7\%) were positive for GT by PCR genotyping. When 11 of the PCR-positive colonies were further analyzed, 6 (54.5\%) were found to be bona fide homologous recombinants by Southern blot analysis, sequencing and fluorescent in situ hybridization. This produces a high efficiency of up to 26.6\% for p53 GT under PNS conditions. We show that p53 disruption and long-term propagation under drug selection conditions do not compromise the pluripotency, as p53-targeted ES cells retained stable growth, undifferentiated phenotype, pluripotency gene expression profile and differentiation potential in vitro and in vivo. Conclusions: Our results demonstrate that medaka ES cells are proficient for HR-mediated GT, offering a first model organism of lower vertebrates towards the development of full ES cell-based GT technology.}, language = {en} } @article{Yan2022, author = {Yan, Zhe}, title = {"I tried to control my emotions": nursing home care workers' experiences of emotional labor in China}, series = {Journal of Cross-Cultural Gerontology}, volume = {37}, journal = {Journal of Cross-Cultural Gerontology}, number = {1}, doi = {10.1007/s10823-022-09452-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324295}, pages = {1-22}, year = {2022}, abstract = {Despite dramatic expansions in the Chinese nursing home sector in meeting the increasing care needs of a rapidly aging population, direct care work in China remains largely devalued and socially unrecognized. Consequently, scant attention has been given to the caregiving experiences of direct care workers (DCWs) in Chinese nursing homes. In particular, given the relational nature of care work, there is little knowledge as to how Chinese DCWs manage emotions and inner feelings through their emotional labor. This article examines the emotional labor of Chinese DCWs through ethnographic data collected with 20 DCWs in one nursing home located in an urban setting in central China. Data were analyzed using conventional content analysis and constant comparison. Participants' accounts of sustaining a caring self, preserving professional identity, and hoping for reciprocity revealed implicit meanings about the often-conflicting nature of emotional labor and the nonreciprocal elements of care work under constrained working conditions. Importantly, the moral-cultural notion of bao (报 norm of reciprocity) was found to be central among DCWs in navigating strained resources and suggested their agency in meaning-construction. However, their constructed moral buffers may be insufficient if emotional labor continues to be made invisible by care organizations.}, subject = {Gerontologie}, language = {en} } @phdthesis{Yang2020, author = {Yang, Manli}, title = {\(Chlamydia\) \(trachomatis\) metabolism during infection and metatranscriptome analysis in \(Neisseria\) \(gonorrhoeae\) coinfected STD patients}, doi = {10.25972/OPUS-18499}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-184993}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Chlamydia trachomatis (Ct) is an obligate intracellular human pathogen. It causes blinding trachoma and sexually transmitted disease such as chlamydia, pelvic inflammatory disease and lymphogranuloma venereum. Ct has a unique biphasic development cycle and replicates in an intracellular vacuole called inclusion. Normally it has two forms: the infectious form, elementary body (EB); and the non-infectious form, reticulate body (RB). Ct is not easily amenable to genetic manipulation. Hence, to understand the infection process, it is crucial to study how the metabolic activity of Ct exactly evolves in the host cell and what roles of EB and RB play differentially in Ct metabolism during infection. In addition, Ct was found regularly coinfected with other pathogens in patients who got sexually transmitted diseases (STDs). A lack of powerful methods to culture Ct outside of the host cell makes the detailed molecular mechanisms of coinfection difficult to study. In this work, a genome-scale metabolic model with 321 metabolites and 277 reactions was first reconstructed by me to study Ct metabolic adaptation in the host cell during infection. This model was calculated to yield 84 extreme pathways, and metabolic flux strength was then modelled regarding 20hpi, 40hpi and later based on a published proteomics dataset. Activities of key enzymes involved in target pathways were further validated by RT-qPCR in both HeLa229 and HUVEC cell lines. This study suggests that Ct's major active pathways involve glycolysis, gluconeogenesis, glycerolphospholipid biosynthesis and pentose phosphate pathway, while Ct's incomplete tricarboxylic acid cycle and fatty acid biosynthesis are less active. EB is more activated in almost all these carbohydrate pathways than RB. Result suggests the survival of Ct generally requires a lot of acetyl-CoA from the host. Besides, both EB and RB can utilize folate biosynthesis to generate NAD(P)H but may use different pathways depending on the demands of ATP. When more ATP is available from both host cell and Ct itself, RB is more activated by utilizing energy providing chemicals generated by enzymes associated in the nucleic acid metabolism. The forming of folate also suggests large glutamate consumption, which is supposed to be converted from glutamine by the glutamine-fructose-6-phosphate transaminase (glmS) and CTP synthase (pyrG). Then, RNA sequencing (RNA-seq) data analysis was performed by me in a coinfection study. Metatranscriptome from patient RNA-seq data provides a realistic overview. Thirteen patient samples were collected and sequenced by our collaborators. Six male samples were obtained by urethral swab, and seven female samples were collected by cervicovaginal lavage. All the samples were Neisseria gonorrhoeae (GC) positive, and half of them had coinfection with Ct. HISAT2 and Stringtie were used for transcriptomic mapping and assembly respectively, and differential expression analysis by DESeq2, Ballgown and Cuffdiff2 are parallelly processed for comparison. Although the measured transcripts were not sufficient to assemble Ct's transcriptome, the differential expression of genes in both the host and GC were analyzed by comparing Ct positive group (Ct+) against Ct-uninfected group. The results show that in the Ct+ group, the host MHC class II immune response was highly induced. Ct infection is associated with the regulation of DNA methylation, DNA double-strand damage and ubiquitination. The analysis also shows Ct infection enhances host fatty acid beta oxidation, thereby inducing mROS, and the host responds to reduce ceramide production and glycolysis. The coinfection upregulates GC's own ion transporters and amino acid uptake, while it downregulates GC's restriction and modification systems. Meanwhile, GC has the nitrosative and oxidative stress response and also increases the ability for ferric uptake especially in the Ct+ group compared to Ct-uninfected group. In conclusion, methods in bioinformatics were used here in analyzing the metabolism of Ct itself, and the responses of the host and GC respectively in a coinfection study with and without Ct. These methods provide metabolic and metatranscriptomic details to study Ct metabolism during infection and Ct associated coinfection in the human microbiota.}, subject = {chlamydia trachomatis}, language = {en} } @article{YangRajeeveRudeletal.2019, author = {Yang, Manli and Rajeeve, Karthika and Rudel, Thomas and Dandekar, Thomas}, title = {Comprehensive Flux Modeling of Chlamydia trachomatis Proteome and qRT-PCR Data Indicate Biphasic Metabolic Differences Between Elementary Bodies and Reticulate Bodies During Infection}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, number = {2350}, issn = {1664-302X}, doi = {10.3389/fmicb.2019.02350}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-189434}, year = {2019}, abstract = {Metabolic adaptation to the host cell is important for obligate intracellular pathogens such as Chlamydia trachomatis (Ct). Here we infer the flux differences for Ct from proteome and qRT-PCR data by comprehensive pathway modeling. We compare the comparatively inert infectious elementary body (EB) and the active replicative reticulate body (RB) systematically using a genome-scale metabolic model with 321 metabolites and 277 reactions. This did yield 84 extreme pathways based on a published proteomics dataset at three different time points of infection. Validation of predictions was done by quantitative RT-PCR of enzyme mRNA expression at three time points. Ct's major active pathways are glycolysis, gluconeogenesis, glycerol-phospholipid (GPL) biosynthesis (support from host acetyl-CoA) and pentose phosphate pathway (PPP), while its incomplete TCA and fatty acid biosynthesis are less active. The modeled metabolic pathways are much more active in RB than in EB. Our in silico model suggests that EB and RB utilize folate to generate NAD(P)H using independent pathways. The only low metabolic flux inferred for EB involves mainly carbohydrate metabolism. RB utilizes energy -rich compounds to generate ATP in nucleic acid metabolism. Validation data for the modeling include proteomics experiments (model basis) as well as qRT-PCR confirmation of selected metabolic enzyme mRNA expression differences. The metabolic modeling is made fully available here. Its detailed insights and models on Ct metabolic adaptations during infection are a useful modeling basis for future studies.}, language = {en} } @phdthesis{Yang2023, author = {Yang, Mengshi}, title = {Synthesis, solubility and optical activity of chiral poly(2,4- disubstituted-2-oxazoline)s}, doi = {10.25972/OPUS-32242}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322429}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {Motivated by the perceived great potential of chiral polymers, the presented work aimed at the investigation of synthesis, solubility and optical activity of chiral poly(2,4-disubstituted-2-oxazoline)s. A novel polymeric carrier based on ABA-type triblock copolymers poly(2-oxazoline)s with chiral and racemic hydrophobic blocks was developed for the formulation of chiral and achiral drugs (Fig. 5.1). Poly(2-methyl-2-oxazoline) (pMeOx) was used as hydrophilic A block, and poly(2-ethyl-4-ethyl-2-oxazoline) (pEtEtOx) and poly(2-propyl-4-methyl-2-oxazoline) (pPrMeOx) were used as hydrophobic B blocks. Curcumin (CUR), paclitaxel (PTX) and chiral/racemic ibuprofen (R/S/RS-IBU) were applied as model drugs. Nanoformulations were prepared consisting of these triblock copolymers and model drugs. ...}, language = {en} } @phdthesis{Yang2022, author = {Yang, Shang}, title = {Characterization and engineering of photoreceptors with improved properties for optogenetic application}, doi = {10.25972/OPUS-20527}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-205273}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Optogenetics became successful in neuroscience with Channelrhodopsin-2 (ChR2), a light-gated cation channel from the green alga Chlamydomonas reinhardtii, as an easy applicable tool. The success of ChR2 inspired the development of various photosensory proteins as powerful actuators for optogenetic manipulation of biological activity. However, the current optogenetic toolbox is still not perfect and further improvements are desirable. In my thesis, I engineered and characterized several different optogenetic tools with new features. (i) Although ChR2 is the most often used optogenetic actuator, its single-channel conductance and its Ca2+ permeability are relatively low. ChR2 variants with increased Ca2+ conductance were described recently but a further increase seemed possible. In addition, the H+ conductance of ChR2 may lead to cellular acidification and unintended pH-related side effects upon prolonged illumination. Through rational design, I developed several improved ChR2 variants with larger photocurrent, higher cation selectivity, and lower H+ conductance. (ii) The light-activated inward chloride pump NpHR is a widely used optogenetic tool for neural silencing. However, pronounced inactivation upon long time illumination constrains its application for long-lasting neural inhibition. I found that the deprotonation of the Schiff base underlies the inactivation of NpHR. Through systematically exploring optimized illumination schemes, I found illumination with blue light alone could profoundly increase the temporal stability of the NpHR-mediated photocurrent. A combination of green and violet light eliminates the inactivation effect, similar to blue light, but leading to a higher photocurrent and therefore better light-induced inhibition. (iii) Photoactivated adenylyl cyclases (PACs) were shown to be useful for light-manipulation of cellular cAMP levels. I developed a convenient in-vitro assay for soluble PACs that allows their reliable characterization. Comparison of different PACs revealed that bPAC from Beggiatoa is the best optogenetic tool for cAMP manipulation, due to its high efficiency and small size. However, a residual activity of bPAC in the dark is unwanted and the cytosolic localization prevents subcellular precise cAMP manipulation. I therefore introduced point mutations into bPAC to reduce its dark activity. Interestingly, I found that membrane targeting of bPAC with different linkers can remarkably alter its activity, in addition to its localization. Taken together, a set of PACs with different activity and subcellular localization were engineered for selection based on the intended usage. The membrane-bound PM-bPAC 2.0 with reduced dark activity is well-tolerated by hippocampal neurons and reliably evokes a transient photocurrent, when co-expression with a CNG channel. (iv) Bidirectional manipulation of cell activity with light of different wavelengths is of great importance in dissecting neural networks in the brain. Selection of optimal tool pairs is the first and most important step for dual-color optogenetics. Through N- and C-terminal modifications, an improved ChR variant (i.e. vf-Chrimson 2.0) was engineered and selected as the red light-controlled actuator for excitation. Detailed comparison of three two-component potassium channels, composed of bPAC and the cAMP-activated potassium channel SthK, revealed the superior properties of SthK-bP. Combining vf-Chrimson 2.0 and improved SthK-bP "SthK(TV418)-bP" could reliably induce depolarization by red light and hyperpolarization by blue light. A residual tiny crosstalk between vf-Chrimson 2.0 and SthK(TV418)-bP, when applying blue light, can be minimized to a negligible level by applying light pulses or simply lowering the blue light intensity.}, language = {en} } @phdthesis{Yang2007, author = {Yang, Shaoxian}, title = {The role of NFAT proteins in Rag and Nfatc1a Gene Regulation in Murine Thymus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-23691}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {In this thesis we have investigated the effect of NFAT (Nuclear Factor of Activated T Cell) transcription factors on the expression of Rag-(Recombination Activating Genes) genes in murine thymus. The protein products of Rag genes, RAG1 and RAG2, are critical for the recombination and generation of the TCR (T Cell Receptor) repertoire during thymocyte development, and their expression can be suppressed by the activity of NFAT factors. In thymus, the expression of Rag1 and Rag2 genes is induced at the double-negative (DN, CD4-8-) 3 stage, down-regulated at the DN4 stage, re-induced at the double-positive (DP, CD4+8+) stage, and suppressed again at the single-positive (SP, CD4+8- or CD4-8+) stage. Although it is known that TCR signaling suppresses the expression of Rag1 and Rag2 at the SP stage, the signals that mediate the Rag gene down-reulation remain elusive. Here we report that both the calcineurin-NFAT-signaling and MAPKinase signaling pathways, which are activated by TCR signaling during positive selection, mediate the Rag gene down-regulation in DP thymocytes. The calcineurin-NFAT pathway suppresses both the Rag1 and the Rag2 gene expression. This pathway has a stronger suppressive effect on the Rag1 than the Rag2 gene. A synergistic activity between the two NFAT factors NFATc2 and NFATc3 is essential for calcineurin-NFAT signaling to efficiently suppress the Rag gene expression in DP thymocytes. It is likely that the calcineurin-NFAT signaling down-regulates Rag gene expression by suppressing both the Rag anti-silencer element (ASE) activity and the Rag promoter activity. Similarly, MEK-ERK signaling of MAPK signaling pathway mediates the Rag gene suppression in DP thymocytes although the mechanism through which MEK-ERK mediates the Rag gene down-regulation has to be elucidated. In DN thymocytes, it appears that neither the calcineurin-NFAT signaling nor MAPK signaling is involved in the Rag gene down-regulation. However, a role for these two signaling pathways in the Rag gene up-regulation in DN thymocytes is not excluded. In DN thymocytes, pre-TCR signaling stimulates the expression both Nfatc1 and Nfatc2 genes but has no effect on Nfatc3 gene expression. In DN thymocytes, pre-TCR signaling activates Nfatc1\&\#945; expression but not Nfatc1ß expression, i.e. the two promoters controling Nfatc1 gene xpression are differently controled by pre-TCR signals. Nfatc1\&\#945; gene expression in DN thymocytes is mainly regulated by the MAPK signaling pathway because activation of Nfatc1\&\#945; is mediated by MEK-ERK signaling but opposed by JNK signaling. Calcineuirn-NFAT and p38 signaling pathways are not involved in Nfatc1\&\#945; promoter regulation in DN thymocytes. In DP thymocytes, TCR signaling up-regulates Nfatc1 and Nfatc2 expression but down-regulates Nfatc3 expression. In DP thymocytes, TCR signaling activates Nfatc1\&\#945; expression. The activation of Nfatc1\&\#945; in DP thymocytes is mediated by NFATc1, but not or to a less degree by NFATc2 and NFATc3. MEK-ERK, JNK, and p38 signaling pathways are involved in Nfatc1\&\#945; gene activation in DP thymocytes, probably by activating NFAT trans-activation activity. All these findings illustrate that in thymocytes the expression of NFAT transcription factors - which are essential for thymic development - is controled at multiple levels.}, language = {en} } @phdthesis{Yang2021, author = {Yang, Tao}, title = {Functional insights into the role of a bacterial virulence factor and a host factor in Neisseria gonorrhoeae infection}, doi = {10.25972/OPUS-20895}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-208959}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Neisseria gonorrhoeae (GC) is a human specific pathogenic bacterium. Currently, N. gonorrhoeae developed resistance to virtually all the available antibiotics used for treatment. N. gonorrhoeae starts infection by colonizing the cell surface, followed by invasion of the host cell, intracellular persistence, transcytosis and exit into the subepithelial space. Subepithelial bacteria can reach the bloodstream and disseminate to other tissues causing systemic infections, which leads to serious conditions such as arthritis and pneumonia. A number of studies have well established the host-pathogen interactions during the initial adherence and invasion steps. However, the mechanism of intracellular survival and traversal is poorly understood so far. Hence, identification of novel bacterial virulence factors and host factors involved in the host-pathogen interaction is a crucial step in understanding disease development and uncovering novel therapeutic approaches. Besides, most of the previous studies about N. gonorrhoeae were performed in the conventional cell culture. Although they have provided insights into host-pathogen interactions, much information about the native infection microenvironment, such as cell polarization and barrier function, is still missing. This work focused on determining the function of novel bacterial virulence factor NGFG_01605 and host factor (FLCN) in gonococcal infection. NGFG_01605 was identified by Tn5 transposon library screening. It is a putative U32 protease. Unlike other proteins in this family, it is not secreted and has no ex vivo protease activity. NGFG_01605 knockout decreases gonococcal survival in the epithelial cell. 3D models based on T84 cell was developed for the bacterial transmigration assay. NGFG_01605 knockout does not affect gonococcal transmigration. The novel host factor FLCN was identified by shRNA library screening in search for factors that affected gonococcal adherence and/or internalization. We discovered that FLCN did not affect N. gonorrhoeae adherence and invasion but was essential for bacterial survival. Since programmed cell death is a host defence mechanism against intracellular pathogens, we further explored apoptosis and autophagy upon gonococcal infection and determined that FLCN did not affect apoptosis but inhibited autophagy. Moreover, we found that FLCN inhibited the expression of E-cadherin. Knockdown of E- cadherin decreased the autophagy flux and supported N. gonorrhoeae survival. Both non-polarized and polarized cells are present in the cervix, and additionally, E-cadherin represents different polarization properties on these different cells. Therefore, we established 3-D models to better understand the functions of FLCN. We discovered that FLCN was critical for N. gonorrhoeae survival in the 3-D environment as well, but not through inhibiting autophagy. Furthermore, FLCN inhibits the E-cadherin expression and disturbs its polarization in the 3-D models. Since N. gonorrhoeae can cross the epithelial cell barriers through both cell-cell junctions and transcellular migration, we further explored the roles FLCN and E-cadherin played in transmigration. FLCN delayed N. gonorrhoeae transmigration, whereas the knockdown of E-cadherin increased N. gonorrhoeae transmigration. In summary, we revealed roles of the NGFG_01605 and FLCN-E-cadherin axis play in N. gonorrhoeae infection, particularly in relation to intracellular survival and transmigration. This is also the first study that connects FLCN and human-specific pathogen infection.}, language = {en} } @article{YangHeydarianKozjakPavlovicetal.2020, author = {Yang, Tao and Heydarian, Motaharehsadat and Kozjak-Pavlovic, Vera and Urban, Manuela and Harbottle, Richard P. and Rudel, Thomas}, title = {Folliculin Controls the Intracellular Survival and Trans-Epithelial Passage of Neisseria gonorrhoeae}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {10}, journal = {Frontiers in Cellular and Infection Microbiology}, number = {422}, issn = {2235-2988}, doi = {10.3389/fcimb.2020.00422}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-211372}, year = {2020}, abstract = {Neisseria gonorrhoeae, a Gram-negative obligate human pathogenic bacterium, infects human epithelial cells and causes sexually transmitted diseases. Emerging multi-antibiotic resistant gonococci and increasing numbers of infections complicate the treatment of infected patients. Here, we used an shRNA library screen and next-generation sequencing to identify factors involved in epithelial cell infection. Folliculin (FLCN), a 64 kDa protein with a tumor repressor function was identified as a novel host factor important for N. gonorrhoeae survival after uptake. We further determined that FLCN did not affect N. gonorrhoeae adherence and invasion but was essential for its survival in the cells by modulating autophagy. In addition, FLCN was also required to maintain cell to cell contacts in the epithelial layer. In an infection model with polarized cells, FLCN inhibited the polarized localization of E-cadherin and the transcytosis of gonococci across polarized epithelial cells. In conclusion, we demonstrate here the connection between FLCN and bacterial infection and in particular the role of FLCN in the intracellular survival and transcytosis of gonococci across polarized epithelial cell layers.}, language = {en} } @phdthesis{Yang2023, author = {Yang, Weiyue}, title = {Population Policy and Governance at the Local Level - A Qualitative Research of the Implementation of the Universal Two-Child Policy in China}, doi = {10.25972/OPUS-31305}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313052}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {The universal two-child policy was introduced by the central government of China in 2016 to respond to the country's deteriorating population problems, but it was soon replaced by a three-child policy in 2021 given that it failed to continuously boost fertility in Chinese society. This dissertation empirically investigates the implementation of universal two-child policy in three Chinese major cities. Based on the data collected through semi-structured interviews with leaders of local family planning agencies, it finds that local officials are primarily devoted to coping with the discontent of the bereaved single-child parents (shidu families), which is an unexpected consequence of the historical one-child policy, rather than working on the tasks regarding birth encouragement. The dissertation suggests understanding the implementation of China's population policy within the framework of both historical and rational choice institutionalism. The target responsibility system as an effective tool of the central authority drives local agents to fix their attention at tasks that have larger impact on their career. The shifted focus in the implementation of the universal two-child policy is a result of local officials' emphasis on the task of maintaining social stability. Shidu families are deemed as a salient threat to social order because their discontent with the state support has incurred continuous petitions at both the national and local level, which would severely undermine local officials' career advancement. However, in the meantime, stability maintenance is found to have become alienated as reflected by the rising costs and that it replaced birth support to be the focus of local family planning agents in the universal two-child policy era. Since the conflict between the shidu group and the state is unlikely to be resolved, the future population policy design and enforcement will continue to be constrained by the shidu problem.}, language = {en} } @article{YangYaoLietal.2022, author = {Yang, Xuting and Yao, Wanqiang and Li, Pengfei and Hu, Jinfei and Latifi, Hooman and Kang, Li and Wang, Ningjing and Zhang, Dingming}, title = {Changes of SOC content in China's Shendong coal mining area during 1990-2020 investigated using remote sensing techniques}, series = {Sustainability}, volume = {14}, journal = {Sustainability}, number = {12}, issn = {2071-1050}, doi = {10.3390/su14127374}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-278939}, year = {2022}, abstract = {Coal mining, an important human activity, disturbs soil organic carbon (SOC) accumulation and decomposition, eventually affecting terrestrial carbon cycling and the sustainability of human society. However, changes of SOC content and their relation with influential factors in coal mining areas remained unclear. In the study, predictive models of SOC content were developed based on field sampling and Landsat images for different land-use types (grassland, forest, farmland, and bare land) of the largest coal mining area in China (i.e., Shendong). The established models were employed to estimate SOC content across the Shendong mining area during 1990-2020, followed by an investigation into the impacts of climate change and human disturbance on SOC content by a Geo-detector. Results showed that the models produced satisfactory results (R\(^2\) > 0.69, p < 0.05), demonstrating that SOC content over a large coal mining area can be effectively assessed using remote sensing techniques. Results revealed that average SOC content in the study area rose from 5.67 gC·kg\(^{-1}\) in 1990 to 9.23 gC·kg\(^{-1}\) in 2010 and then declined to 5.31 gC·Kg\(^{-1}\) in 2020. This could be attributed to the interaction between the disturbance of soil caused by coal mining and the improvement of eco-environment by land reclamation. Spatially, the SOC content of farmland was the highest, followed by grassland, and that of bare land was the lowest. SOC accumulation was inhibited by coal mining activities, with the effect of high-intensity mining being lower than that of moderate- and low-intensity mining activities. Land use was found to be the strongest individual influencing factor for SOC content changes, while the interaction between vegetation coverage and precipitation exerted the most significant influence on the variability of SOC content. Furthermore, the influence of mining intensity combined with precipitation was 10 times higher than that of mining intensity alone.}, language = {en} } @phdthesis{Yang2015, author = {Yang, Zhenghong}, title = {A systematic study of learned helplessness in Drosophila melanogaster}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-112424}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2015}, abstract = {The learned helplessness phenomenon is a specific animal behavior induced by prior exposure to uncontrollable aversive stimuli. It was first found by Seligman and Maier (1967) in dogs and then has been reported in many other species, e.g. in rats (Vollmayr and Henn, 2001), in goldfishes (Padilla, 1970), in cockroaches (Brown, 1988) and also in fruit flies (Brown, 1996; Bertolucci, 2008). However, the learned helplessness effect in fruit flies (Drosophila melanogaster) has not been studied in detail. Thus, in this doctoral study, we investigated systematically learned helplessness behavior of Drosophila for the first time. Three groups of flies were tested in heatbox. Control group was in the chambers experiencing constant, mild temperature. Second group, master flies were punished in their chambers by being heated if they stopped walking for 0.9s. The heat pulses ended as soon as they resumed walking again. A third group, the yoked fly, was in their chambers at the same time. However, their behavior didn't affect anything: yoked flies were heated whenever master flies did, with same timing and durations. After certain amount of heating events, yoked flies associated their own behavior with the uncontrollability of the environment. They suppressed their innate responses such as reducing their walking time and walking speed; making longer escape latencies and less turning around behavior under heat pulses. Even after the conditioning phase, yoked flies showed lower activity level than master and control flies. Interestingly, we have also observed sex dimorphisms in flies. Male flies expressed learned helplessness not like female flies. Differences between master and yoked flies were smaller in male than in female flies. Another interesting finding was that prolonged or even repetition of training phases didn't enhance learned helplessness effect in flies. Furthermore, we investigated serotonergic and dopaminergic nervous systems in learned helplessness. Using genetic and pharmacological manipulations, we altered the levels of serotonin and dopamine in flies' central nervous system. Female flies with reduced serotonin concentration didn't show helpless behavior, while the learned helplessness effect in male flies seems not to be affected by a reduction of serotonin. Flies with lower dopamine level do not display the learned helplessness effect in the test phase, suggesting that with low dopamine the motivational change in learned helplessness in Drosophila may decline faster than with a normal dopamine level.}, subject = {Taufliege}, language = {en} } @article{YankuBitmanLotanZoharetal.2018, author = {Yanku, Yifat and Bitman-Lotan, Eliya and Zohar, Yaniv and Kurant, Estee and Zilke, Norman and Eilers, Martin and Orian, Amir}, title = {Drosophila HUWE1 ubiquitin ligase regulates endoreplication and antagonizes JNK signaling during salivary gland development}, series = {Cells}, volume = {7}, journal = {Cells}, number = {10}, issn = {2073-4409}, doi = {10.3390/cells7100151}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197630}, pages = {151}, year = {2018}, abstract = {The HECT-type ubiquitin ligase HECT, UBA and WWE Domain Containing 1, (HUWE1) regulates key cancer-related pathways, including the Myc oncogene. It affects cell proliferation, stress and immune signaling, mitochondria homeostasis, and cell death. HUWE1 is evolutionarily conserved from Caenorhabditis elegance to Drosophila melanogaster and Humans. Here, we report that the Drosophila ortholog, dHUWE1 (CG8184), is an essential gene whose loss results in embryonic lethality and whose tissue-specific disruption establishes its regulatory role in larval salivary gland development. dHUWE1 is essential for endoreplication of salivary gland cells and its knockdown results in the inability of these cells to replicate DNA. Remarkably, dHUWE1 is a survival factor that prevents premature activation of JNK signaling, thus preventing the disintegration of the salivary gland, which occurs physiologically during pupal stages. This function of dHUWE1 is general, as its inhibitory effect is observed also during eye development and at the organismal level. Epistatic studies revealed that the loss of dHUWE1 is compensated by dMyc proeitn expression or the loss of dmP53. dHUWE1 is therefore a conserved survival factor that regulates organ formation during Drosophila development.}, language = {en} } @phdthesis{Yarali2008, author = {Yarali, Ayse}, title = {Aspects of predictive learning in the fruit fly}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-28741}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Past experience contributes to behavioural organization mainly via learning: Animals learn otherwise ordinary cues as predictors for biologically significant events. This thesis studies such predictive, associative learning, using the fruit fly Drosophila melanogaster. I ask two main questions, which complement each other: One deals with the processing of those cues that are to be learned as predictors for an important event; the other one deals with the processing of the important event itself, which is to be predicted. Do fruit flies learn about combinations of olfactory and visual cues? I probe larval as well as adult fruit flies for the learning about combinations of olfactory and visual cues, using a so called 'biconditional discrimination' task: During training, one odour is paired with reinforcement only in light, but not in darkness; the other odour in turn is reinforced only in darkness, but not in light. Thus, neither the odours nor the visual conditions alone predict reinforcement, only combinations of both do. I find no evidence that either larval or adult fruit flies were to solve such task, speaking against a cross-talk between olfactory and visual modalities. Previous studies however suggest such cross-talk. To reconcile these results, I suggest classifying different kinds of interaction between sensory modalities, according to their site along the sensory-motor continuum: I consider an interaction 'truly' cross-modal, if it is between the specific features of the stimuli. I consider an interaction 'amodal' if it instead engages the behavioural tendencies or 'values' elicited by each stimulus. Such reasoning brings me to conclude that different behavioural tasks require different kinds of interaction between sensory modalities; whether a given kind of interaction will be found depends on the neuronal infrastructure, which is a function of the species and the developmental stage. Predictive learning of pain-relief in fruit flies Fruit flies build two opposing kinds of memory, based on an experience with electric shock: Those odours that precede shock during training are learned as predictors for punishment and are subsequently avoided; those odours that follow shock during training on the other hand are learned as signals for relief and are subsequently approached. I focus on such relief learning. I start with a detailed parametric analysis of relief learning, testing for reproducibility as well as effects of gender, repetition of training, odour identity, odour concentration and shock intensity. I also characterize how relief memories, once formed, decay. In addition, concerning the psychological mechanisms of relief learning, first, I show that relief learning establishes genuinely associative conditioned approach behaviour and second, I report that it is most likely not mediated by context associations. These results enable the following neurobiological analysis of relief learning; further, they will form in the future the basis for a mathematical model; finally, they will guide the researchers aiming at uncovering relief learning in other experimental systems. Next, I embark upon neurogenetic analysis of relief learning. First, I report that fruit flies mutant for the so called white gene build overall more 'negative' memories about an experience with electric shock. That is, in the white mutants, learning about the painful onset of shock is enhanced, whereas learning about the relieving offset of shock is diminished. As they are coherently affected, these two kinds of learning should be in a balance. The molecular mechanism of the effect of white on this balance remains unresolved. Finally, as a first step towards a neuronal circuit analysis of relief learning, I compare it to reward learning and punishment learning. I find that relief learning is distinct from both in terms of the requirement for biogenic amine signaling: Reward and punishment are respectively signalled by octopamine and dopamine, for relief learning, either of these seem dispensible. Further, I find no evidence for roles for two other biogenic amines, tyramine and serotonin in relief learning. Based on these findings I give directions for further research.}, subject = {Lernen}, language = {en} } @phdthesis{YazdaniRashvanlouei2017, author = {Yazdani Rashvanlouei, Kourosh}, title = {Developing a Framework for International Projects of ERP Implementation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-154000}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2017}, abstract = {Enterprise Systeme werden immer mehr von Bedeutung, was sie in die Mitte der Aufmerksamkeit und der Ber{\"u}cksichtigung durch Organisationen in verschiedensten Formen r{\"u}ckt - seien es Unternehmen oder Industrien von riesigen {\"o}ffentlichen oder privaten Organisationen bis hin zu mittleren und kleinen Dienstleistungsunternehmen. Diese Systeme verbessern sich st{\"a}ndig, sowohl funktionell, als auch technologisch und sie sind unumg{\"a}nglich f{\"u}r Unternehmen, um ihre Produktivit{\"a}t zu vergr{\"o}ßern und um in dem nationalen und globalen Wettbewerb mitzuhalten. Da lokale Softwarel{\"o}sungen die Bedingungen, speziell von großen Betrieben, funktionell und technologisch nicht erf{\"u}llen konnten und da riesige globale Softwarehersteller, wie SAP, Oracle und Microsoft ihre L{\"o}sungen rapide verbessern und sie ihren Markt immer mehr {\"u}ber den Globus expandieren, nimmt die Nachfrage f{\"u}r diese globalen Marken und deren nahezu einwandfreien Softwarel{\"o}sungen t{\"a}glich zu. Die Zustimmung f{\"u}r internationale ERP Unternehmensberatungsanwendungen nimmt deswegen exponentiell zu, w{\"a}hrend die Forschung der beeinflussenden Faktoren und des Fachwissens wenig verbreitet ist. Deswegen ist es so dringlich, dieses Gebiet zu erforschen. Das schlussendliche f{\"u}nf-in-f{\"u}nf Framework dieser Studie sammelt zum ersten Mal in der Geschichte alle historisch erw{\"a}hnten, kritischen Erfolgsfaktoren und Projektaktivit{\"a}ten. Diese wurden in f{\"u}nf Phasen unterteilt und nach den f{\"u}nf Schwerpunkten der internationalen ERP Projektdurchf{\"u}hrung kategorisiert. Dieses Framework bietet einen {\"U}berblick und bildet einen umfassenden Fahrplan f{\"u}r solche Projekte.}, subject = {ERP}, language = {en} } @phdthesis{Ye2004, author = {Ye, Fang}, title = {The role of DNA supercoiling in the coordinated regulation of gene expression in Helicobacter pylori}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-9878}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2004}, abstract = {Summary Mechanisms of global gene regulation in bacteria are not well characterized yet. Changes in global or local supercoiling of chromosomal DNA are thought to play a role in global gene silencing and gene activation. In Helicobacter pylori, a bacterium with few dedicated transcriptional regulators, the structure of some promoters indicates a dependency on DNA topology. For example, the promoter of the major flagellar subunit gene flaA ({\´o}28-dependent) has a shorter spacing of 13 nucleotides (nt) in comparison to the consensus promoter (15 nt). Supercoiling changes might be a mechanism of gene-specific and global transcriptional regulation in this bacterium. The aim of this study was to elucidate, if changes in global supercoiling have an influence on global gene regulation in H. pylori, and on the temporal regulation of the flagellar biosynthesis pathway in this organism. In the present work, global DNA supercoiling in H. pylori was visualized for the first time, by determining the supercoiling state of plasmids under different growth conditions. Using this method, we showed that cellular supercoiling was clearly growth phase-dependent in H. pylori. Coinciding with increased supercoiling during the growth phases, transcription of the flaA gene was increased, while the transcription of a second {\´o}28-dependent gene with regular promoter spacing (HP0472) was reduced, supporting the hypothesis that growth phase-dependency of promoters might be mediated by changes of DNA topology. Supercoiling in H. pylori could be influenced in a reproducible fashion by inhibition of gyrase using novobiocin, which led to DNA relaxation and to a concomitant decrease of flaA transcript levels. Promoter spacer mutagenesis of the flaA promoter was performed. With flaA promoters of increased or reduced length, transcription of flaA was reduced, less susceptible to supercoiling changes, and, under specific conditions, inverted as compared to the wild type promoter. Transcriptional interdependence between the coupled topA-flaB genes and flaA was found by analysis of the flaA promoter mutants. Chromosomally linked gyrA-flgR, and topA-flaB genes were all dependent on supercoiling and coregulated with each other. Comprehensive transcript profiling (DNA microarrays) of wildtype H. pylori with and without novobiocin treatment identified a number of genes (10\% of total genes), including flagellin, virulence and housekeeping genes, which were strongly dependent on and appeared to be synchronized by supercoiling changes (transcriptional up- or downregulation). These findings indicate a tightly coupled temporal regulation of flagellar biogenesis and metabolism in H. pylori, dependent on global supercoiling. A specific group of genes was also regulated in H. pylori by overexpression of Topoisomerase I, as detected by genome-wide analysis (DNA microarray). The DNA-bending protein HU is thought to be responsible for influencing the negative supercoiling of DNA, through its ability to wrap DNA. HU is encoded by the hup single gene in H. pylori, and constitutively expressed during the whole growth curve. An H. pylori hup mutant was constructed. H. pylori cells lacking HU protein were viable, but exhibited a severe growth defect. Our data indicate that the lack of HU dramatically changes global DNA supercoiling, indicating an important function of HU in chromosome structuring in H. pylori. Transcriptome analyses were performed and demonstrated that a total of 66 genes were differentially transcribed upon hup deletion, which include virulence genes and many other cell functions. The data indicate that HU might act as further important global regulator in H. pylori. Increased gene expression of heat shock proteins and a decreased transcription of the urease gene cluster may indicate a co-ordinated response of H. pylori to changes of environmental conditions in its specific ecological niche, mediated by HU. After the whole genomic sequences of H. pylori strains 26695 and J99 were published, two ORFs (HP0116 and HP0440) were presumptively annotated as topoisomerase I orthologs. HP0116 is the functional H. pylori topoisomerase I (TopA). HP0440 (topA2) was found in only few (5 of 43) strains. Western blot analysis indicated that TopA2 is antigenically different from TopA. TopA2 is transcribed in H. pylori, but the protein must be functionally different from TopA, since it is lacking one functionally essential zinc finger motif, and was not able to functionally complement a TopA-deficient E. coli. Like topA, topA2 was also transcribed in a growth phase-dependent manner. We did not find a function of TopA2 in DNA structuring or topology, but, in the present study, we were able for the first time to establish a unique function for TopA2 in global gene regulation, by comprehensive transcriptome analysis (DNA microarray). Transcriptome analysis showed that a total of 46 genes were differentially regulated upon topA2 deletion, which included flagellar genes and urease genes. These results suggest that TopA2 might act as a novel important regulator of both flagellar biosynthesis and urease in H. pylori.}, subject = {Helicobacter pylori}, language = {en} } @phdthesis{Ye2023, author = {Ye, Liqing}, title = {RNA-RNA interactions in viral genome packaging}, doi = {10.25972/OPUS-29636}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-296361}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {RNA is one of the most abundant macromolecules and plays essential roles in numerous biological processes. This doctoral thesis consists of two projects focusing on RNA structure and RNA-RNA interactions in viral genome packaging. In the first project I developed a method called Functional Analysis of RNA Structure (FARS-seq) to investigate structural features regulating genome dimerization within the HIV-1 5'UTR. Genome dimerization is a conserved feature of retroviral replication and is thought to be a prerequisite for binding to the viral structural protein Pr55Gag during genome packaging. It also plays a role in genome integrity and evolution through recombination, and is linked to a structural switch that may regulate genome packaging and translation within cells. Despite its importance for HIV-1 replication, the RNA signals regulating genome dimerization, and the molecular mechanism leading to the selection of the genome dimer over the monomer for packaging are incompletely understood. The FARS-seq method combines RNA structural information obtained by chemical probing with single nucleotide resolution profiles of RNA function obtained by mutational interference. In this way, we found nucleotides that were critical for dimerization, especially within the well-characterized dimerization motif within stem-loop 1 (SL1). We also found stretches of nucleotides that enhanced genome dimerization upon mutation, suggesting their role in negatively regulating dimerization. A structural analysis identified distinct structural signatures within monomeric and dimeric RNA. The dimeric conformation displayed the canonical transactivation response (TAR), PolyA, primer binding site (PBS), and SL1-SL3 stem-loops, and contained a long range U5-AUG interaction. Unexpectedly, in monomeric RNA, SL1 was reconfigured into long- and short-range base-pairings with PolyA and PBS, respectively. Intriguingly, these base pairings concealed the palindromic sequence needed for dimerization and disrupted the internal loop in SL1 previously shown to contain the major packaging motif for Pr55Gag. We therefore rationally introduced mutations into PolyA and PBS, and showed how these regions regulate genome dimerization, and the binding of Pr55Gag in vitro, as well as genome packaging into virions. These findings give insights into late stages of the HIV-1 life cycle and a mechanistic explanation for the link between RNA dimerization and packaging. In the second project, I developed a proximity ligation and high-throughput sequencing-based method, RNA-RNA seq, which can measure direct (RNA-RNA) and indirect (protein-mediated) interactions. In contrast to existing methods, RNA-RNA seq is not limited by specific protein or RNA baits, nor to a particular crosslinking reagent. The genome of influenza A virus contains eight segments, which assemble into a "7+1" supramolecular complex. However, the molecular details of genome assembly are poorly understood. Our goal is to use RNA-RNA seq to identify the sites of interaction between the eight genomic RNAs of influenza, and to use this information to define the quaternary RNA architecture of the genome. We showed that RNA-RNA seq worked on model substrates, like the HIV-1 Dimerization Initiation Site (DIS) RNA and purified ribosome, as well as influenza A virus infected cells.}, subject = {RNS-Viren}, language = {en} } @article{YeAmbiOlguinNavaetal.2021, author = {Ye, Liqing and Ambi, Uddhav B. and Olguin-Nava, Marco and Gribling-Burrer, Anne-Sophie and Ahmad, Shazeb and Bohn, Patrick and Weber, Melanie M. and Smyth, Redmond P.}, title = {RNA structures and their role in selective genome packaging}, series = {Viruses}, volume = {13}, journal = {Viruses}, number = {9}, issn = {1999-4915}, doi = {10.3390/v13091788}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246101}, year = {2021}, abstract = {To generate infectious viral particles, viruses must specifically select their genomic RNA from milieu that contains a complex mixture of cellular or non-genomic viral RNAs. In this review, we focus on the role of viral encoded RNA structures in genome packaging. We first discuss how packaging signals are constructed from local and long-range base pairings within viral genomes, as well as inter-molecular interactions between viral and host RNAs. Then, how genome packaging is regulated by the biophysical properties of RNA. Finally, we examine the impact of RNA packaging signals on viral evolution.}, language = {en} } @phdthesis{Ye2022, author = {Ye, Mingyu}, title = {Immunotherapy with Vaccinia virus co-expressing tumor-associated antigens and mouse IL-2 cytokine in mice with mammary cancer}, doi = {10.25972/OPUS-25309}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-253095}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Interleukin 2 (IL-2) was the first cytokine applied for cancer treatment in human history. It has been approved as monotherapy for renal cell carcinoma and melanoma by the FDA and does mediate the regression of the tumors in patients. One of the possible mechanisms is that the administration of IL-2 led to T lymphocytes expansion, including CD4+ and CD8+ T cells. In addition, a recent study demonstrated that antigen-specific T cells could also be expanded through the induction of IL-2, which plays a crucial role in mediating tumor regression. However, despite the long-term and extensive use of IL-2 in the clinic, the ratio of patients who get a complete response was still low, and only about one-fifth of patients showed objective tumor regression. Therefore, the function of IL-2 in cancer treatment should continue to be optimized and investigated. A study by Franz O. Smith et al. has shown that the combination treatment of IL-2 and tumor-associated antigen vaccine has a strong trend to increased objective responses compared to patients with melanoma receiving IL-2 alone. Peptide vaccines are anti-cancer vaccines able to induce a powerful tumor antigenspecific immune response capable of eradicating the tumors. According to the type of antigens, peptide vaccines can be classified into two distinct categories: Tumor-associated antigens (TAA) vaccine and tumor-specific neoantigens (TSA) vaccine. Currently, Peptide vaccines are mainly investigated in phase I and phase II clinical trials of human cancer patients with various advanced cancers such as lung cancer, gastrointestinal tumors, and breast cancers. Vaccinia virus (VACV) is one of the safest viral vectors, which has been wildly used in cancer treatment and pathogen prevention. As an oncolytic vector, VACV can carry multiple large foreign genes, which enable the virus to introduce diagnostic and therapeutic agents without dramatically reducing the viral replication. Meanwhile, the recombinant vaccinia virus (rVACV) can be easily generated by homologous recombination. Here, we used the vaccinia virus as the therapeutic cancer vector, expressing mouse Interleukin 2 (IL-2) and tumor-associated antigens simultaneously to investigate the combined effect of anti-tumor immune response in the 4T1 mouse tumor model. As expected, the VACV driven mIL-2 expression remarkably increased both CD4+ and CD8+ populations in vivo, and the virus-expressed tumor-associated peptides successfully elicited theantigen-specific T cell response to inhibit the growth of tumors. Furthermore, the experiments with tumor-bearing animals showed that the mIL-2 plus tumor antigens expressing VACV vector gave a better anti-cancer response than the mIL-2 alone expressing vector. The combinations did significantly more inhibit tumor growth than mIL-2 treatment alone. Moreover, the results confirmed our previous unpublished data that the mIL-2 expression driven by synthetic early/late promoter in the Lister strain VACV could enhance the tumor regression in the 4T1 mouse model.}, language = {en} } @article{YeKeicherGentschevetal.2021, author = {Ye, Mingyu and Keicher, Markus and Gentschev, Ivaylo and Szalay, Aladar A.}, title = {Efficient selection of recombinant fluorescent vaccinia virus strains and rapid virus titer determination by using a multi-well plate imaging system}, series = {Biomedicines}, volume = {9}, journal = {Biomedicines}, number = {8}, issn = {2227-9059}, doi = {10.3390/biomedicines9081032}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245104}, year = {2021}, abstract = {Engineered vaccinia virus (VACV) strains are used extensively as vectors for the development of novel cancer vaccines and cancer therapeutics. In this study, we describe for the first time a high-throughput approach for both fluorescent rVACV generation and rapid viral titer measurement with the multi-well plate imaging system, IncuCyte\(^®\)S3. The isolation of a single, well-defined plaque is critical for the generation of novel recombinant vaccinia virus (rVACV) strains. Unfortunately, current methods of rVACV engineering via plaque isolation are time-consuming and laborious. Here, we present a modified fluorescent viral plaque screening and selection strategy that allows one to generally obtain novel fluorescent rVACV strains in six days, with a minimum of just four days. The standard plaque assay requires chemicals for fixing and staining cells. Manual plaque counting based on visual inspection of the cell culture plates is time-consuming. Here, we developed a fluorescence-based plaque assay for quantifying the vaccinia virus that does not require a cell staining step. This approach is less toxic to researchers and is reproducible; it is thus an improvement over the traditional assay. Lastly, plaque counting by virtue of a fluorescence-based image is very convenient, as it can be performed directly on the computer.}, language = {en} } @article{YeWilhelmGentschevetal.2021, author = {Ye, Mingyu and Wilhelm, Martina and Gentschev, Ivaylo and Szalay, Alad{\´a}r}, title = {A modified limiting dilution method for monoclonal stable cell line selection using a real-time fluorescence imaging system: A practical workflow and advanced applications}, series = {Methods and Protocols}, volume = {4}, journal = {Methods and Protocols}, number = {1}, doi = {10.3390/mps4010016}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-228896}, year = {2021}, abstract = {Stable cell lines are widely used in laboratory research and pharmaceutical industry. They are mainly applied in recombinant protein and antibody productions, gene function studies, drug screens, toxicity assessments, and for cancer therapy investigation. There are two types of cell lines, polyclonal and monoclonal origin, that differ regarding their homogeneity and heterogeneity. Generating a high-quality stable cell line, which can grow continuously and carry a stable genetic modification without alteration is very important for most studies, because polyclonal cell lines of multicellular origin can be highly variable and unstable and lead to inconclusive experimental results. The most commonly used technologies of single cell originate monoclonal stable cell isolation in laboratory are fluorescence-activated cell sorting (FACS) sorting and limiting dilution cloning. Here, we describe a modified limiting dilution method of monoclonal stable cell line selection using the real-time fluorescence imaging system IncuCyte\(^®\)S3.}, language = {en} } @phdthesis{Ye2012, author = {Ye, Qing}, title = {Synthesis and Investigation of Borylene Complexes: from Borylene Transfer to Borylene Catenation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-71443}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Im Rahmen dieser Arbeit wurde das Spektrum des Borylentransfers ausgeweitet, indem {\"U}bergangsmetall Alkinylkomplexe und Metall-Kohlenstoff-Doppelbindungen als Borylen-Akzeptoren eingeschlossen wurden. Neben der Salzeliminierung, Halogenidabstraktion und Dehydrierung, wurde eine neuartige Syntheseroute zu terminalen Borylenkomplexen durch Salz- und Silylhalogenideliminierung etabliert. Mithilfe dieser Strategie gelang die Darstellung von [(OC)3(Me3P)Fe=BDur], ein seltenes Beispiel f{\"u}r einen neutralen Arylborylenkomplex. Im Speziellen hat diese Verbindung ein großes Anwendungspotenzial f{\"u}r Metathesereaktionen und die Funktionalisierung von polycyclischen aromatischen Kohlenwasserstoffen, wie z. B. Naphthalin, gezeigt. Außerdem konnte ein Eisen-Bis(borylen)-Komplex [(OC)3Fe(BDur){BN(SiMe3)2}] durch einen Phosphan-Borylen-Austausch dargestellt werden. Ausgehend von diesem Komplex gelang die Darstellung von 1,4-Diboracyclohexadien bzw. des ersten 1,4-Dibora-1,3-Butadien-Komplexes, wodurch eine neue Art von Borylentransfer etabliert werden konnte. H{\"o}chst interessant ist es, dass der Transfer von weiteren Borylen-Einheiten in die Koordinationssph{\"a}re des Eisenatoms zu einer kontrollierten Borylen-Verkettung gef{\"u}hrt hat.}, subject = {Borylene}, language = {en} } @phdthesis{Ye2013, author = {Ye, Yuxiang}, title = {Molecular and Cellular Magnetic Resonance Imaging of Myocardial Infarct Healing}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-72514}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Myokardinfarkte (MI) sind eine der h{\"a}ufigsten Todesursachen weltweit. Eine rechtzeitige Wiederherstellung des koronaren Blutflusses im isch{\"a}mischen Myokard reduziert signifikant die Sterblichkeitsrate akuter Infarkte und vermindert das ventrikul{\"a}re Remodeling. {\"U}berlebende MI-Patienten entwickeln jedoch h{\"a}ufig eine Herzinsuffizienz, die mit einer reduzierten Lebensqualit{\"a}t, hohen Sterblichkeitsrate (10\% j{\"a}hrlich), sowie hohen Kosten f{\"u}r das Gesundheitssystem einhergeht. Die Entwicklung der Herzinsuffizienz nach einem MI ist auf den hohen Verlust kontraktiler Kardiomyozyten, w{\"a}hrend der Isch{\"a}mie-Reperfusion zur{\"u}ckzuf{\"u}hren. Anschließende komplexe strukturelle und funktionelle Ver{\"a}nderungen resultieren aus Modifikationen des infarzierten und nicht infarzierten Myokards auf molekularer und zellul{\"a}rer Ebene. Die verbesserte {\"U}berlebensrate von Patienten mit akutem MI und das Fehlen effizienter Therapien, die die Entwicklung und das Fortschreiten des ventrikul{\"a}ren Remodelings verhindern, f{\"u}hren zu einer hohen Pr{\"a}valenz der Herzinsuffizienz. Die kardiale Magnetresonanztomographie (MRT) ist eine wichtige Methode zur Diagnose und Beurteilung des Myokardinfarktes. Mit dem technologischen Fortschritt wurden die Grenzen der MRT erweitert, so dass es heute m{\"o}glich ist, auch molekulare und zellul{\"a}re Ereignisse in vivo und nicht-invasiv zu untersuchen. In Kombination mit kardialer Morphologie und Funktion k{\"o}nnte die Visualisierung essentieller molekularer und zellul{\"a}rer Marker in vivo weitreichende Einblicke in den Heilungsprozess infarzierter Herzen liefern, was zu neuen Erkenntnissen f{\"u}r ein besseres Verst{\"a}ndnis und bessere Therapien des akuten MI f{\"u}hren k{\"o}nnte. In dieser Arbeit wurden Methoden f{\"u}r die molekulare und zellul{\"a}re kardiale MRT-Bildgebung der Inflammation und des Kalziumstroms im Heilungsprozess des akuten Myokardinfarktes in vivo in einem Rattenmodel mit klinischer Relevanz etabliert.}, subject = {Kernspintomografie}, language = {en} } @article{YilmazRoeschKlingeletal.2011, author = {Yilmaz, Ali and R{\"o}sch, Sabine and Klingel, Karin and Kandolf, Reinhard and Helluy, Xavier and Hiller, Karl-Heinz and Jakob, Peter M and Sechtem, Udo}, title = {Molecular magnetic resonance imaging (MRI) of inflamed myocardium using ferucarbotran in patients with acute myocardial infarction}, series = {Journal of Cardiovascular Magnetic Resonance}, volume = {13}, journal = {Journal of Cardiovascular Magnetic Resonance}, number = {Suppl. 1}, doi = {10.1186/1532-429X-13-S1-P149}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140991}, pages = {P149}, year = {2011}, abstract = {Introduction: Superparamagnetic iron oxide nanoparticle (SPIO)-based molecular imaging agents targeting macrophages have been developed and successfully applied in animal models of myocardial infarction.}, language = {en} } @article{YilmazAksoyCamlitepeetal.2014, author = {Yilmaz, Ayse and Aksoy, Volkan and Camlitepe, Yilmaz and Giurfa, Martin}, title = {Eye structure, activity rhythms, and visually-driven behavior are tuned to visual niche in ants}, series = {Frontiers in Behavioral Neuroscience}, volume = {8}, journal = {Frontiers in Behavioral Neuroscience}, doi = {10.3389/fnbeh.2014.00205}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119595}, pages = {205}, year = {2014}, abstract = {Insects have evolved physiological adaptations and behavioral strategies that allow them to cope with a broad spectrum of environmental challenges and contribute to their evolutionary success. Visual performance plays a key role in this success. Correlates between life style and eye organization have been reported in various insect species. Yet, if and how visual ecology translates effectively into different visual discrimination and learning capabilities has been less explored. Here we report results from optical and behavioral analyses performed in two sympatric ant species, Formica cunicularia and Camponotus aethiops. We show that the former are diurnal while the latter are cathemeral. Accordingly, F. cunicularia workers present compound eyes with higher resolution, while C. aethiops workers exhibit eyes with lower resolution but higher sensitivity. The discrimination and learning of visual stimuli differs significantly between these species in controlled dual-choice experiments: discrimination learning of small-field visual stimuli is achieved by F. cunicularia but not by C. aethiops, while both species master the discrimination of large-field visual stimuli. Our work thus provides a paradigmatic example about how timing of foraging activities and visual environment match the organization of compound eyes and visually-driven behavior. This correspondence underlines the relevance of an ecological/evolutionary framework for analyses in behavioral neuroscience.}, language = {en} } @phdthesis{Yin2023, author = {Yin, Jing}, title = {Progressive alterations of pro- and antidegeneration markers in the nigrostriatal tract of the AAV1/2-A53T-α synuclein rat model of Parkinson's disease}, doi = {10.25972/OPUS-26064}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260645}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {Neurodegeneration plays an essential role in Parkinson's disease (PD). Several crucial neuronal pro-and antidegeneration markers were described to be altered in disease models accompanied by neurodegeneration. In the AAV1/2-A53T-aSyn PD rat model progressive time-dependent motor impairment and neurodegeneration in the nigrostriatal tract starting from 2 weeks after PD model induction could be found. Downregulation of Nrf2 in SN and nigrostriatal axon localization, a trend of Tau downregulation in SN and upregulation in axon localization in the AAV1/2-A53T-aSyn PD rat model were observed, indicating potential therapeutic value of these two molecular targets in PD. No alterations of SARM1 and NMNAT2 could be detected, indicating little relevance of these two molecules with our AAV1/2-A53T-aSyn rat model.}, language = {en} } @article{YinBrocherFischeretal.2011, author = {Yin, Jun and Brocher, Jan and Fischer, Utz and Winkler, Christoph}, title = {Mutant Prpf31 causes pre-mRNA splicing defects and rod photoreceptor cell degeneration in a zebrafish model for Retinitis pigmentosa}, series = {Molecular neurodegeneration}, volume = {6}, journal = {Molecular neurodegeneration}, number = {56}, doi = {10.1186/1750-1326-6-56}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141090}, pages = {1-17}, year = {2011}, abstract = {Background: Retinitis pigmentosa (RP) is an inherited eye disease characterized by the progressive degeneration of rod photoreceptor cells. Mutations in pre-mRNA splicing factors including PRPF31 have been identified as cause for RP, raising the question how mutations in general factors lead to tissue specific defects. Results: We have recently shown that the zebrafish serves as an excellent model allowing the recapitulation of key events of RP. Here we use this model to investigate two pathogenic mutations in PRPF31, SP117 and AD5, causing the autosomal dominant form of RP. We show that SP117 leads to an unstable protein that is mislocalized to the rod cytoplasm. Importantly, its overexpression does not result in photoreceptor degeneration suggesting haploinsufficiency as the underlying cause in human RP patients carrying SP117. In contrast, overexpression of AD5 results in embryonic lethality, which can be rescued by wild-type Prpf31. Transgenic retina-specific expression of AD5 reveals that stable AD5 protein is initially localized in the nucleus but later found in the cytoplasm concurrent with progressing rod outer segment degeneration and apoptosis. Importantly, we show for the first time in vivo that retinal transcripts are wrongly spliced in adult transgenic retinas expressing AD5 and exhibiting increased apoptosis in rod photoreceptors. Conclusion: Our data suggest that distinct mutations in Prpf31 can lead to photoreceptor degeneration through different mechanisms, by haploinsufficiency or dominant-negative effects. Analyzing the AD5 effects in our animal model in vivo, our data imply that aberrant splicing of distinct retinal transcripts contributes to the observed retina defects.}, language = {en} } @unpublished{YinWernerHiguchietal.2018, author = {Yin, Yafu and Werner, Rudolf A. and Higuchi, Takahiro and Lapa, Constantin and Pienta, Kenneth J. and Pomper, Martin G. and Gorin, Michael A. and Rowe, Steven P.}, title = {Follow-Up of Lesions with Equivocal Radiotracer Uptake on PSMA-Targeted PET in Patients with Prostate Cancer: Predictive Values of the PSMA-RADS-3A and PSMARADS- 3B Categories}, series = {Journal of Nuclear Medicine}, journal = {Journal of Nuclear Medicine}, issn = {0161-5505}, doi = {10.2967/jnumed.118.217653}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167594}, year = {2018}, abstract = {Purpose: Prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) imaging has become commonly utilized in patients with prostate cancer (PCa). The PSMA reporting and data system version 1.0 (PSMA-RADS version 1.0) categorizes lesions on the basis of the likelihood of PCa involvement, with PSMA-RADS-3A (soft tissue) and PSMA-RADS-3B (bone) lesions being indeterminate for the presence of disease. We retrospectively reviewed the imaging follow-up of such lesions to determine the rate at which they underwent changes suggestive of underlying PCa. Methods: PET/CT imaging with \(^{18}\)F-DCFPyL was carried out in 110 patients with PCa and lesions were categorized according to PSMA-RADS Version 1.0. 56/110 (50.9\%) patients were determined to have indeterminate PSMA-RADS-3A or PSMA-RADS-3B lesions and 22/56 (39.3\%) patients had adequate follow-up to be included in the analysis. The maximum standardized uptake values (SUV\(_{max}\)) of the lesions were obtained and the ratios of SUV\(_{max}\) of the lesions to SUV\(_{mean}\) of blood pool (SUV\(_{max}\)-lesion/SUV\(_{mean}\)-bloodpool) were calculated. Pre-determined criteria were used to evaluate the PSMA-RADS-3A and PSMA-RADS-3B lesions on follow-up imaging to determine if they demonstrated evidence of underlying malignancy. Results: A total of 46 lesions in 22 patients were considered indeterminate for PCa (i.e. PSMA-RADS-3A (32 lesions) or PSMA-RADS-3B (14 lesions)) and were evaluable on follow-up imaging. 27/46 (58.7\%) lesions demonstrated changes on follow-up imaging consistent with the presence of underlying PCa at baseline. These lesions included 24/32 (75.0\%) PSMA-RADS-3A lesions and 3/14 (21.4\%) lesions categorized as PSMA-RADS-3B. The ranges of SUVmax and SUVmax-lesion/SUVmean-bloodpool overlapped between those lesions demonstrating changes consistent with malignancy on follow-up imaging and those lesions that remained unchanged on follow-up. Conclusion: PSMA-RADS-3A and PSMA-RADS-3B lesions are truly indeterminate in that proportions of findings in both categories demonstrate evidence of malignancy on follow-up imaging. Overall, PSMA-RADS-3A lesions are more likely than PSMA-RADS-3B lesions to represent sites of PCa and this information should be taken into when guiding patient therapy.}, subject = {Positronen-Emissions-Tomografie}, language = {en} } @article{YongJacobowitzBaroneetal.1994, author = {Yong, Liu and Jacobowitz, David M. and Barone, Frank and McCarron, Richard and Spatz, Maria and Feuerstein, Giora and Hallenbeck, John M. and Sir{\´e}n, Anna-Leena}, title = {Quantitation of perivascular monocyte / macrophages around cerebral blood vessels of hypertensive and aged rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86800}, year = {1994}, abstract = {The numbers of monocytes and macrophages in the walls of cerebral blood vessels were counted on perfusion-fixed frozen brain sections (16 JLffi) of spontaneously hypertensive rats (SHR), stroke-prone SHR (SHR-SP), normotensive Wistar-Kyoto (WKY) rats, and young (16-week-old) and old (2-year-old) normotensive Sprague-Dawley rats (SD-l6w and SD-2y, respectively) using monoclonal antiborlies against rat macrophages (ED2). The staining was visualized with fluoresceinlabeled second antiborlies. The ED2-specific staining in brain sections was restricted to macrophages in a perivascular location. The number of perivascular cells per square millimeter of high-power field was significantly greater in SHR-SP (8.6 ± 2.1; n = 4) and SHR (6. 7 ± 0.9; n = 6) than in normotensive WKY (4.0 ± 0.5; n = 6; p <0.01). The number of perivascular macrophages was also greater in SD-2y (7.5 ± 2.7; n = 9) than in SD-l6w (2.9 ± 1.8; n = 8; p < 0.01). No ED2 staining was found in the resident microglia or in the endothelial cells, which were identified by double staining with rhodamine-labeled anti-factor VIII-related antigen antiborlies. The results suggest that the stroke risk factors hypertension and advanced age are associated with increased subendothelial accumulation of monocytes and macrophages. This accumulation could increase the tendency for the endothelium to convert from an anticoagulant to a procoagulant surface in response to mediators released from these subendothelial cells.}, subject = {Willebrand-Faktor}, language = {en} } @article{YoungClementsLangetal.2014, author = {Young, Joanna C. and Clements, Abigail and Lang, Alexander E. and Garnett, James A. and Munera, Diana and Arbeloa, Ana and Pearson, Jaclyn and Hartland, Elizabeth L. and Matthews, Stephen J. and Mousnier, Aurelie and Barry, David J. and Way, Michael and Schlosser, Andreas and Aktories, Klaus and Frankel, Gad}, title = {The Escherichia coli effector EspJ blocks Src kinase activity via amidation and ADP ribosylation}, series = {Nature Communications}, volume = {5}, journal = {Nature Communications}, number = {5887}, doi = {10.1038/ncomms6887}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121157}, year = {2014}, abstract = {The hallmark of enteropathogenic Escherichia coli (EPEC) infection is the formation of actin-rich pedestal-like structures, which are generated following phosphorylation of the bacterial effector Tir by cellular Src and Abl family tyrosine kinases. This leads to recruitment of the Nck-WIP-N-WASP complex that triggers Arp2/3-dependent actin polymerization in the host cell. The same phosphorylation-mediated signalling network is also assembled downstream of the Vaccinia virus protein A36 and the phagocytic Fc-gamma receptor FcγRIIa. Here we report that the EPEC type-III secretion system effector EspJ inhibits autophosphorylation of Src and phosphorylation of the Src substrates Tir and FcγRIIa. Consistent with this, EspJ inhibits actin polymerization downstream of EPEC, Vaccinia virus and opsonized red blood cells. We identify EspJ as a unique adenosine diphosphate (ADP) ribosyltransferase that directly inhibits Src kinase by simultaneous amidation and ADP ribosylation of the conserved kinase-domain residue, Src E310, resulting in glutamine-ADP ribose.}, language = {en} }