@phdthesis{Loebbert2013, author = {L{\"o}bbert, Anne-Katrin}, title = {F{\"u}hrt VIRTUAL-REALITY-Simulationstraining zur Stressreduktion bei angehenden interventionellen Kardiologen? : eine stratifiziert randomisierte Studie}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-99978}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Die Simulationstechnologie in der Medizin hat in den letzten Jahren große Fortschritte gemacht. In der Zwischenzeit gibt es auch f{\"u}r Herzkatheteruntersuchungen und -interventionen „Virtual reality" Simulatoren, die ein realistisches Training von Kathetereingriffen erlauben. Nicht gekl{\"a}rt ist bislang, ob Simulationstraining das Stressniveau des Untersuchers reduzieren kann. Im Rahmen dieser Studie wurde zur Beantwortung der genannten Fragestellung der Effekt von Virtual-Reality-Training auf das Stressniveau von Anf{\"a}ngern in der interventionellen Kardiologie untersucht. Hierzu wurde eine randomisiert-stratifizierte Studie bei 33 Anf{\"a}ngern in der interventionellen Kardiologie durchgef{\"u}hrt. Die Probanden wurden in eine Kontroll- und Simulationsgruppe aufgeteilt. Die Simulationsgruppe erhielt ein achtst{\"u}ndiges intensives Training an verschiedenen Simulatoren, w{\"a}hrend die Kontrollgruppe kein Simulationstraining, sondern lediglich eine theoretische Wissensvermittlung erhielt. Alle Teilnehmer mussten unter realit{\"a}tsnahen Umst{\"a}nden im Herzkatheterlabor der Universit{\"a}tsklinik W{\"u}rzburg innerhalb von 30 Minuten eine PCI an einem pulsatilen Herzkreislaufmodell durchf{\"u}hren. Die Probanden dokumentierten vor und nach der Pr{\"a}- und Postevaluation ihr aktuelles „Befinden" anhand eines psychologi-schen Fragebogens PANAS. Ebenso wurden die Probanden hinsichtlich ihrer manuellen F{\"a}higkeiten nach einem strukturierten Evaluationsbogen von einem interventionell t{\"a}tigen Kardiologen bewertet Die Ergebnisse zeigten initial f{\"u}r die Parameter „aktiv, interessiert, freudig erregt, stark, angeregt, stolz, begeistert, wach, entschlossen und aufmerksam" des Fragebogens PANAS keinen gruppenspezifischen Unterschied. Nach einem achtst{\"u}ndigen Simulationstraining gab die Simulationsgruppe eine signifikante Reduktion des Stressniveaus im Vergleich zur Kontrollgruppe an. Die aktuelle Studie zeigte, dass das Training an den Virtual Reality Simulatoren die herk{\"o}mmliche Ausbildung in effektiver Weise erg{\"a}nzen kann. Weitere Studien mit einer gr{\"o}ßeren und zugleich homogeneren Stichprobengr{\"o}ße sind n{\"o}tig, um die genannten Hypothesen zu best{\"a}tigen.}, subject = {Simulator}, language = {de} } @phdthesis{Schlereth2013, author = {Schlereth, Florian}, title = {Expression of the DHEA/DHEAS-Shuttle in cell lines and foetal tissue of human liver, adrenal and cartilage}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-102068}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {DHEA is a precursor for the male and female sex hormones testosterone and estradiol, which are mainly secreted from the testes and the ovary, respectively. In addition, epidemiological studies showed that low serum levels of DHEA and DHEAS correlate with the incidence of autoimmune disease, cancer and cardiovascular disease. In vitro, DHEA and DHEAS influenced glucose metabolism in a favourable manner. However, positive effects of DHEA substitution were only significant adrenal insufficiency in women. Steroid sulphotransferase 2A1 (SULT2A1) is the responsible enzyme for sulphonation of DHEA to DHEAS which is thought to be the inactive form of DHEA. In this role, SULT2A1 acts as a central regulator of steroid synthesis because sulphonation of DHEA withdraws the substrate for further downstream conversion. Another essential cofactor for sulphonation is PAPS, which is produced by the enzyme PAPS synthase (PAPSS) from ATP and anorganic sulphate. PAPSS exists in the different isoforms PAPSS1 and PAPSS2 and splice variants PAPSS2a and PAPSS2b. Changes in PAPSS activity are thought to influence sulphonation of DHEA significantly. However, neither regulation of PAPSS nor its influence on SULT2A1 have been investigated in human cell lines or humans. The main goal of this thesis was to analyze the enzyme expression of the DHEA/DHEA shuttle, i.e. mRNA and protein of SULT2A1, PAPSS1 and PAPSS2, in various human cell lines. Furthermore, I investigated which cell line could serve as a suitable model for further research regarding regulation of SULT2A1, PAPSS1 and PAPSS2. Here, I could show that the enzymes of the DHEA/DHEAS shuttle were expressed in the human adrenal cell line NCI-h295R as both mRNA and protein. In enzyme assays, I was able to prove conversion of DHEA to DHEAS as well as to different other steroids. However, applying Trilostane, a potent inhibitor of CYP3B, effectively directed conversion of DHEA to DHEAS. Using these findings, future experiments can investigate for example the influence of certain cytokines or endocrine disruptors on expression and activity of PAPSS1/2 and on sulphonation of DHEA. In particular, the relatively equal expression of PAPSS1 and PAPSS2 will enable us to do knock down experiments with siRNA to elucidate how the activity of one enzyme changes when the other one fails. Sulphonation of DHEA by SULT2A1 is thought to happen in the cytoplasm or more precisely in the Golgi apparatus. However, experiments in transfected cells have shown both a cytoplasmatic and a nuclear localisation when both enzymes were expressed at the same time. Immunocytochemistry revealed the same results in the adrenal cell line NCI-h295R, where both enzymes were expressed strongly in the nucleus. The physiological role is not clear and requires further research. Presumably, sulphate is activated in the nucleus. However, one could also speculate that a shift of PAPSS to the nucleus could generate a reservoir, which can be activated by re-localisation to the cytoplasm when more PAPS is needed. Expression of SULT2A1 in some foetal tissues has been investigated earlier. Whilst in adult human cartilage PAPSS1 is predominant, in newly born hamsters PAPSS2 is more abundantly expressed. The expression of PAPSS isoforms in highly sulphonating tissue has not been investigated in humans, so far. This work demonstrated a differential expression of SULT2A1, PAPSS1 and PAPSS2 in adult and foetal liver, adrenal and foetal cartilage tissue. In adult and foetal adrenal expression was similar. However, foetal and adult liver differed in the expression of SULT2A1, which was expressed much more in adult tissue. Most importantly, in foetal cartilage there was only a low expression of SULT2A1 and PAPS seems to mostly provided by PAPSS1, which was considerably higher expressed in cartilage than in other tissues. In contrast, PAPSS2 was mainly expressed in adult and foetal adrenal. Additionally, we reported a case of a female patient who had been investigated for hyperandrogenism. Two mutations in the PAPSS2 gene had led to massively reduced serum levels of DHEAS. One heterozygous mutation in the domain of the APS kinase of the PAPSS2 protein leads to substitution of one amino acid at position 48 (T48R). In vitro experiments showed a residual activity of 6\% for this mutation. A second mutation in the ATP sulphurylase domain of PAPSS2 was found. The introduction of thymidine instead of cytidine leads to a stop codon, which is presumed to truncate the protein at position 329 (R329X). In vitro, no residual activity was seen for this mutation. The lack of PAPS reduces sulphonation of DHEA but also sulphonation of proteoglycanes, which leads to skeletal abnormalities. The abundance of DHEA enables massive downstream conversion to androgens leading to clinical features of hyperandrogenism. Regarding the bone abnormalities, it is interesting and surprising that activity of PAPSS1 compensated to a great extent in cartilage but was not able to keep up a more considerable sulphonation of DHEA. Possibly, the subcellular localisation might play a role in this scenario.}, subject = {Dehydroepiandrosteron}, language = {en} } @phdthesis{Michalska2013, author = {Michalska, Marta}, title = {Molecular Imaging of atherosclerosis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73243}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Atherosklerose ist eine aktive und progressive Erkrankung, bei der vaskul{\"a}re Adh{\"a}sionsmolek{\"u}le wie VCAM-1 eine entscheidende Rolle durch Steuerung der Rekrutierung von Immunzellen in den fr{\"u}hen und fortgeschrittenen Plaques spielen. Ein zielgerichteter Einsatz von VCAM-1-Molek{\"u}len mit spezifischen Kontrastmitteln ist daher eine M{\"o}glichkeit, die VCAM-1-Expression zu kontrollieren, Plaquewachstum ab einem fr{\"u}hen Zeitpunkt zu visualisieren und eine fr{\"u}he Pr{\"a}vention von Atherosklerose vor Beginn der Thrombusbildung zu etablieren. Des Weiteren bietet die nichtinvasive Magnetresonanz (MR)-Bildgebung den Vorteil der Kombination molekularer und morphologischer Daten. Sie erm{\"o}glicht, mithilfe von entwickelten VCAM-1-markierten Eisenoxidpartikeln, den spezifischen Nachweis entz{\"u}ndlicher Prozesse w{\"a}hrend der Atherosklerose. Diese Arbeit belegt, dass mit dem VCAM-1-Konzept eine vielversprechende Herangehensweise gefunden wurde und dass das, mit spezifischen superparamagnetischen Eisenoxid (USPIO) konjugierte VCAM-1-Peptid, gegen{\"u}ber unspezifischer USPIOs ein erh{\"o}htes Potenzial bei der Untersuchung der Atherosklerose in sich tr{\"a}gt. Im ersten Teil der Arbeit konnte im Mausmodell gezeigt werden, dass gerade das VCAM-1-Molek{\"u}l ein sinnvoller Ansatzpunkt zur Darstellung und Bildgebung von Atherosklerose ist, da in der fr{\"u}hen Phase der Entz{\"u}ndung die vaskul{\"a}ren Zelladh{\"a}sionsmolek{\"u}le {\"u}berexprimiert und auch kontinuierlich, w{\"a}hrend der fortschreitenden Plaquebildung, hochreguliert werden. Weiterhin beschreibt diese Arbeit die Funktionst{\"u}chtigkeit und das Verm{\"o}gen des neu gestalteten USPIO Kontrastmittels mit dem zyklischen Peptid, in seiner Spezialisierung auf die VCAM-1 Erkennung. Experimentelle Studien mit ultra-Hochfeld-MRT erm{\"o}glichten weitere ex vivo und in vivo Nachweise der eingesetzten USPIO-VCAM-1-Partikel innerhalb der Region um die Aortenwurzel in fr{\"u}hen und fortgeschrittenen atherosklerotischen Plaques von 12 und 30 Wochen alten Apolipoprotein E-defizienten (ApoE-/-) M{\"a}usen. Mit ihrer Kombination aus Histologie und Elektronenmikroskopie zeigt diese Studie zum ersten Mal die Verteilung von VCAM-1-markierten USPIO Partikeln nicht nur in luminalem Bereich der Plaques, sondern auch in tieferen Bereichen der medialen Muskelzellen. Dieser spezifische und sensitive Nachweis der fr{\"u}hen und fortgeschrittenen Stadien der Plaquebildung bringt auf molekularer Ebene neue M{\"o}glichkeiten zur Fr{\"u}herkennung von atherosklerotischen Plaques vor dem Entstehen von 8 Rupturen. Im Gegensatz zum USPIO-VCAM-1-Kontrastmittel scheiterten unspezifische USPIO Partikel an der Identifikation fr{\"u}her Plaqueformen und begrenzten die Visualisierung von Atherosklerose auf fortgeschrittene Stadien in ApoE-/- M{\"a}usen.}, subject = {VCAM}, language = {en} } @phdthesis{Wiemer2013, author = {Wiemer, Laura Elisa}, title = {In-vitro-Untersuchungen zur molekularen Wirkung von Mitotane beim Nebennierenrindenkarzinom}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-94526}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Das Nebennierenrindenkarzinom ist eine hochmaligne Erkrankung und hat eine schlechte Prognose. Mitotane ist bis heute die einzige hierf{\"u}r zugelassene Therapie. Um die molekularen Mechanismen der Mitotanetherapie besser zu verstehen, wurde die Nebennierenkarzinom-Zelllinie NCI-H295 mit unterschiedlichen Konzentrationen von Mitotane inkubiert und die Wirkung auf mehreren Ebenen untersucht. Dabei kam der Untersuchung der Steroidogenese und apoptotischer Vorg{\"a}nge ein besonderer Fokus zu. In den Hormonanalysen via Immunoassay zeigte sich eine zeit- und konzentrationsabh{\"a}ngige Hemmung der adrenalen Steroidsekretion. So kam es unter 24-st{\"u}ndiger Inkubation mit 100µM Mitotane zu einer Reduktion der Cortisolsekretion um 89\%. Diese Hormonsuppression geht einher mit einer Herabregulation von steroidogenen Enzymen in den durchgef{\"u}hrten Microarray-basierten Genexpressionsanalysen. So konnte gezeigt werden, dass vor allem Steroidbiosynthese-Enzyme der Zona fasciculata und reticularis betroffen sind. Als weitere wichtige Gene im Zusammenhang mit der Beeinflussung des Steroidhaushalts unter Mitotanetherapie konnten SQLE, LDLR, SCD, SREBF1 und ABCG1 identifiziert werden. Gleichzeitig konnte durch Durchflusszytometrie und Zelltod-ELISA die proapoptotische Wirkung von Mitotane gezeigt werden (FACS: 100µM Mitotane, 24 Stunden; Zunahme der Apoptose um den Faktor 2,13). Dies best{\"a}tigte sich beispielsweise auch in der {\"U}berexpression des Apoptosegens BAX in der Real-Time-PCR. Weiterhin zeigte der RNA-Microarray eine starke Expressionszunahme bei Genen, die mit dem programmierten Zelltod zusammenh{\"a}ngen wie GDF15, DUSP4, TRIB3 und CHOP. Ausgehend von den klinischen Effekten und best{\"a}tigt durch die oben genannten in vitro Ergebnisse bewirkt Mitotane auch molekular folgende {\"A}nderungen in Nebennierenrindenzellen: Hemmung der Steroidogenese und Induktion von Apotose. Es stellt sich damit die Frage, ob diese Mechanismen parallel und separat voneinander ablaufen oder ob es einen gemeinsamen Nenner gibt. Interessanterweise ergab die Analyse der Genexpressionsdaten, dass viele der proapoptotischen Gene mit dem sogenannten ER-Stress zusammenh{\"a}ngen. Einerseits k{\"o}nnte Mitotane durch direkte Inhibition der Hormonsekretion wirken, andererseits k{\"o}nnte ER-Stress durch Mitotane-induzierte-Bildung toxischer Lipide, wie Cholesterol, ausgel{\"o}st werden. Um den genauen Wirkmechanismus endg{\"u}ltig zu kl{\"a}ren, werden weitere Experimente ben{\"o}tigt. Mitotane-induzierter ER-Stress liefert einen vollst{\"a}ndig neuen Blickwinkel auf die molekulare Wirkweise von Mitotane auf Nebennierenrindenkarzinomzellen. Gerade da die Mediatoren des ER-Stresses gut definiert und ER-Stress spezifisch sind, k{\"o}nnten sie sinnvolle Ziele in der Therapie darstellen. Die Beobachtung, dass Mitotane ER-Stress hervorruft, k{\"o}nnte in Zukunft somit zur Entwicklung wirksamerer und spezifischerer Therapien des Nebennierenrindenkarzinoms f{\"u}hren und so die infauste Prognose dieser malignen Krankheit verbessern.}, subject = {Nebenniere}, language = {de} } @article{ChopraLangSalzmannetal.2013, author = {Chopra, Martin and Lang, Isabell and Salzmann, Steffen and Pachel, Christina and Kraus, Sabrina and B{\"a}uerlein, Carina A. and Brede, Christian and Jord{\´a}n Garrote, Ana-Laura and Mattenheimer, Katharina and Ritz, Miriam and Schwinn, Stefanie and Graf, Carolin and Sch{\"a}fer, Viktoria and Frantz, Stefan and Einsele, Hermann and Wajant, Harald and Beilhack, Andreas}, title = {Tumor Necrosis Factor Induces Tumor Promoting and Anti-Tumoral Effects on Pancreatic Cancer via TNFR1}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0075737}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97246}, year = {2013}, abstract = {Multiple activities are ascribed to the cytokine tumor necrosis factor (TNF) in health and disease. In particular, TNF was shown to affect carcinogenesis in multiple ways. This cytokine acts via the activation of two cell surface receptors, TNFR1, which is associated with inflammation, and TNFR2, which was shown to cause anti-inflammatory signaling. We assessed the effects of TNF and its two receptors on the progression of pancreatic cancer by in vivo bioluminescence imaging in a syngeneic orthotopic tumor mouse model with Panc02 cells. Mice deficient for TNFR1 were unable to spontaneously reject Panc02 tumors and furthermore displayed enhanced tumor progression. In contrast, a fraction of wild type (37.5\%), TNF deficient (12.5\%), and TNFR2 deficient mice (22.2\%) were able to fully reject the tumor within two weeks. Pancreatic tumors in TNFR1 deficient mice displayed increased vascular density, enhanced infiltration of CD4+ T cells and CD4+ forkhead box P3 (FoxP3)+ regulatory T cells (Treg) but reduced numbers of CD8+ T cells. These alterations were further accompanied by transcriptional upregulation of IL4. Thus, TNF and TNFR1 are required in pancreatic ductal carcinoma to ensure optimal CD8+ T cell-mediated immunosurveillance and tumor rejection. Exogenous systemic administration of human TNF, however, which only interacts with murine TNFR1, accelerated tumor progression. This suggests that TNFR1 has basically the capability in the Panc02 model to trigger pro-and anti-tumoral effects but the spatiotemporal availability of TNF seems to determine finally the overall outcome.}, language = {en} } @article{SbieraRonchiLeichetal.2013, author = {Sbiera, Silviu and Ronchi, Cristina L. and Leich, Ellen and Henzel, Katharina and Rosenwald, Andreas and Allolio, Bruno and Fassnacht, Martin}, title = {Single Nucleotide Polymorphism Array Profiling of Adrenocortical Tumors - Evidence for an Adenoma Carcinoma Sequence?}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0073959}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97218}, year = {2013}, abstract = {Adrenocortical tumors consist of benign adenomas and highly malignant carcinomas with a still incompletely understood pathogenesis. A total of 46 adrenocortical tumors (24 adenomas and 22 carcinomas) were investigated aiming to identify novel genes involved in adrenocortical tumorigenesis. High-resolution single nucleotide polymorphism arrays (Affymetrix) were used to detect copy number alterations (CNAs) and copy neutral losses of heterozygosity (cnLOH). Genomic clustering showed good separation between adenomas and carcinomas, with best partition including only chromosome 5, which was highly amplified in 17/22 malignant tumors. The malignant tumors had more relevant genomic aberrations than benign tumors, such as a higher median number of recurrent CNA (2631 vs 94), CNAs >100 Kb (62.5 vs 7) and CN losses (72.5 vs 5.5), and a higher percentage of samples with cnLOH (91\% vs 29\%). Within the carcinoma cohort, a precise genetic pattern (i.e. large gains at chr 5, 7, 12, and 19, and losses at chr 1, 2, 13, 17, and 22) was associated with a better prognosis (overall survival: 72.2 vs 35.4 months, P=0.063). Interestingly, >70\% of gains frequent in beningn were also present in malignant tumors. Notch signaling was the most frequently involved pathway in both tumor entities. Finally, a CN gain at imprinted "IGF2" locus chr 11p15.5 appeared to be an early alteration in a multi-step tumor progression, followed by the loss of one or two alleles, associated with increased IGF2 expression, only in carcinomas. Our study serves as database for the identification of genes and pathways, such as Notch signaling, which could be involved in the pathogenesis of adrenocortical tumors. Using these data, we postulate an adenoma-carcinoma sequence for these tumors.}, language = {en} } @phdthesis{Schoenfeld2013, author = {Sch{\"o}nfeld, Stephan}, title = {Aldosteron und Cortisol bei Dialysepatienten - Effekt auf kardiale und vaskul{\"a}re Ereignisse}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96156}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Dialysepatienten weisen eine hohe Anzahl kardiovaskul{\"a}rer Ereignisse auf. Betrachtet man die h{\"a}ufigsten Todesursachen von Dialysepatienten, so f{\"a}llt ein großer Teil in den kardiovaskul{\"a}ren Bereich. In dieser Arbeit wurde der Einfluss von Aldosteron und Cortisol auf kardiale und vaskul{\"a}re Ereignisse bei Dialysepatienten mit Diabetes mellitus untersucht. Dazu wurden Daten von 1255 Dialysepatienten mit Diabetes mellitus aus der Deutschen Diabetes Dialyse Studie analysiert. In der vorliegenden Arbeit konnte gezeigt werden, dass mit erh{\"o}hten Aldosteronkonzentrationen ein signifikanter Anstieg des Risikos f{\"u}r pl{\"o}tzlichen Herztod (HR: 1.69; 95\% CI: 1.06-2.69) einhergeht. Das Risiko an pl{\"o}tzlichem Herztod zu versterben war bei hohen Konzentrationen von Aldosteron und gleichzeitig vorliegenden hohen Konzentrationen von Cortisol noch deutlicher erh{\"o}ht (HR: 2.86, 95\% CI: 1.32-6.21). Ebenso war die Gesamtsterblichkeit signifikant erh{\"o}ht bei Patienten, die hohe Aldosteron- und Cortisolkonzentrationen aufwiesen im Vergleich zu Patienten mit niedrigen Spiegeln beider Hormone (HR: 1.62, 95\% CI: 1.01-2.62). In dieser Arbeit konnte somit ein deutlicher Zusammenhang hoher Aldosteron- und Cortisolkonzentrationen mit pl{\"o}tzlichem Herztod und Gesamtsterblichkeit gezeigt werden.}, subject = {Aldosteron}, language = {de} } @article{WinterKampfHelluyetal.2013, author = {Winter, Patrick and Kampf, Thomas and Helluy, Xavier and Gutjahr, Fabian T. and Meyer, Cord B. and Rommel, Eberhard and Bauer, Wolfgang R. and Jakob, Peter M. and Herold, Volker}, title = {Fast retrospectively triggered local pulse-wave velocity measurements in mice with CMR-microscopy using a radial trajectory}, series = {Journal of Cardiovascular Magnetic Resonance}, journal = {Journal of Cardiovascular Magnetic Resonance}, doi = {10.1186/1532-429X-15-88}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96602}, year = {2013}, abstract = {Background The aortic pulse-wave velocity (PWV) is an important indicator of cardiovascular risk. In recent studies MRI methods have been developed to measure this parameter noninvasively in mice. Present techniques require additional hardware for cardiac and respiratory gating. In this work a robust self-gated measurement of the local PWV in mice without the need of triggering probes is proposed. Methods The local PWV of 6-months-old wild-type C57BL/6J mice (n=6) was measured in the abdominal aorta with a retrospectively triggered radial Phase Contrast (PC) MR sequence using the flow-area (QA) method. A navigator signal was extracted from the CMR data of highly asymmetric radial projections with short repetition time (TR=3 ms) and post-processed with high-pass and low-pass filters for retrospective cardiac and respiratory gating. The self-gating signal was used for a reconstruction of high-resolution Cine frames of the aortic motion. To assess the local PWV the volume flow Q and the cross-sectional area A of the aorta were determined. The results were compared with the values measured with a triggered Cartesian and an undersampled triggered radial PC-Cine sequence. Results In all examined animals a self-gating signal could be extracted and used for retrospective breath-gating and PC-Cine reconstruction. With the non-triggered measurement PWV values of 2.3±0.2 m/s were determined. These values are in agreement with those measured with the triggered Cartesian (2.4±0.2 m/s) and the triggered radial (2.3±0.2 m/s) measurement. Due to the strong robustness of the radial trajectory against undersampling an acceleration of more than two relative to the prospectively triggered Cartesian sampling could be achieved with the retrospective method. Conclusion With the radial flow-encoding sequence the extraction of a self-gating signal is feasible. The retrospective method enables a robust and fast measurement of the local PWV without the need of additional trigger hardware.}, language = {en} } @article{GassenmaierGorskiAleksicetal.2013, author = {Gassenmaier, Tobias and Gorski, Armin and Aleksic, Ivan and Deubner, Nikolas and Weidemann, Frank and Beer, Meinrad}, title = {Impact of cardiac magnet resonance imaging on management of ventricular septal rupture after acute myocardial infarction}, series = {World Journal of Cardiology}, journal = {World Journal of Cardiology}, doi = {10.4330/wjc.v5.i5.151}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96562}, year = {2013}, abstract = {A 74-year-old man was admitted to the cardiac catheterization laboratory with acute myocardial infarction. After successful angioplasty and stent implantation into the right coronary artery, he developed cardiogenic shock the following day. Echocardiography showed ventricular septal rupture. Cardiac magnet resonance imaging (MRI) was performed on the critically ill patient and provided detailed information on size and localization of the ruptured septum by the use of fast MRI sequences. Moreover, the MRI revealed that the ventricular septal rupture was within the myocardial infarction area, which was substantially larger than the rupture. As the patient's condition worsened, he was intubated and had intra-aortic balloon pump implanted, and extracorporeal membrane oxygenation was initiated. During the following days, the patient's situation improved, and surgical correction of the ventricular septal defect could successfully be performed. To the best of our knowledge, this case report is the first description of postinfarction ventricular septal rupture by the use of cardiac MRI in an intensive care patient with cardiogenic shock and subsequent successful surgical repair.}, language = {en} } @article{UeceylerKahnKrameretal.2013, author = {{\"U}{\c{c}}eyler, Nurcan and Kahn, Ann-Kathrin and Kramer, Daniela and Zeller, Daniel and Casanova-Molla, Jordi and Wanner, Christoph and Weidemann, Frank and Katsarava, Zaza and Sommer, Claudia}, title = {Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case-control study}, series = {BMC Neurology}, journal = {BMC Neurology}, doi = {10.1186/1471-2377-13-47}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96527}, year = {2013}, abstract = {Background Fabry disease is an inborn lysosomal storage disorder which is associated with small fiber neuropathy. We set out to investigate small fiber conduction in Fabry patients using pain-related evoked potentials (PREP). Methods In this case-control study we prospectively studied 76 consecutive Fabry patients for electrical small fiber conduction in correlation with small fiber function and morphology. Data were compared with healthy controls using non-parametric statistical tests. All patients underwent neurological examination and were investigated with pain and depression questionnaires. Small fiber function (quantitative sensory testing, QST), morphology (skin punch biopsy), and electrical conduction (PREP) were assessed and correlated. Patients were stratified for gender and disease severity as reflected by renal function. Results All Fabry patients (31 men, 45 women) had small fiber neuropathy. Men with Fabry disease showed impaired cold (p < 0.01) and warm perception (p < 0.05), while women did not differ from controls. Intraepidermal nerve fiber density (IENFD) was reduced at the lower leg (p < 0.001) and the back (p < 0.05) mainly of men with impaired renal function. When investigating A-delta fiber conduction with PREP, men but not women with Fabry disease had lower amplitudes upon stimulation at face (p < 0.01), hands (p < 0.05), and feet (p < 0.01) compared to controls. PREP amplitudes further decreased with advance in disease severity. PREP amplitudes and warm (p < 0.05) and cold detection thresholds (p < 0.01) at the feet correlated positively in male patients. Conclusion Small fiber conduction is impaired in men with Fabry disease and worsens with advanced disease severity. PREP are well-suited to measure A-delta fiber conduction.}, language = {en} } @article{EliasHeuschmannSchmittetal.2013, author = {Elias, Johannes and Heuschmann, Peter U. and Schmitt, Corinna and Eckhardt, Frithjof and Boehm, Hartmut and Maier, Sebastian and Kolb-M{\"a}urer, Annette and Riedmiller, Hubertus and M{\"u}llges, Wolfgang and Weisser, Christoph and Wunder, Christian and Frosch, Matthias and Vogel, Ulrich}, title = {Prevalence dependent calibration of a predictive model for nasal carriage of methicillin-resistant Staphylococcus aureus}, series = {BMC Infectious Diseases}, journal = {BMC Infectious Diseases}, doi = {10.1186/1471-2334-13-111}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96091}, year = {2013}, abstract = {Background Published models predicting nasal colonization with Methicillin-resistant Staphylococcus aureus among hospital admissions predominantly focus on separation of carriers from non-carriers and are frequently evaluated using measures of discrimination. In contrast, accurate estimation of carriage probability, which may inform decisions regarding treatment and infection control, is rarely assessed. Furthermore, no published models adjust for MRSA prevalence. Methods Using logistic regression, a scoring system (values from 0 to 200) predicting nasal carriage of MRSA was created using a derivation cohort of 3091 individuals admitted to a European tertiary referral center between July 2007 and March 2008. The expected positive predictive value of a rapid diagnostic test (GeneOhm, Becton \& Dickinson Co.) was modeled using non-linear regression according to score. Models were validated on a second cohort from the same hospital consisting of 2043 patients admitted between August 2008 and January 2012. Our suggested correction score for prevalence was proportional to the log-transformed odds ratio between cohorts. Calibration before and after correction, i.e. accurate classification into arbitrary strata, was assessed with the Hosmer-Lemeshow-Test. Results Treating culture as reference, the rapid diagnostic test had positive predictive values of 64.8\% and 54.0\% in derivation and internal validation corhorts with prevalences of 2.3\% and 1.7\%, respectively. In addition to low prevalence, low positive predictive values were due to high proportion (> 66\%) of mecA-negative Staphylococcus aureus among false positive results. Age, nursing home residence, admission through the medical emergency department, and ICD-10-GM admission diagnoses starting with "A" or "J" were associated with MRSA carriage and were thus included in the scoring system, which showed good calibration in predicting probability of carriage and the rapid diagnostic test's expected positive predictive value. Calibration for both probability of carriage and expected positive predictive value in the internal validation cohort was improved by applying the correction score. Conclusions Given a set of patient parameters, the presented models accurately predict a) probability of nasal carriage of MRSA and b) a rapid diagnostic test's expected positive predictive value. While the former can inform decisions regarding empiric antibiotic treatment and infection control, the latter can influence choice of screening method.}, language = {en} } @article{HaringPettingerBeaetal.2013, author = {Haring, Bernhard and Pettinger, Mary and Bea, Jennifer W. and Wactawski-Wende, Jean and Carnahan, Ryan M. and Ockene, Judith K. and Wyler von Ballmoos, Moritz and Wallace, Robert B. and Wassertheil-Smoller, Sylvia}, title = {Laxative use and incident falls, fractures and change in bone mineral density in postmenopausal women: results from the Women's Health Initiative}, series = {BMC Geriatrics}, journal = {BMC Geriatrics}, doi = {10.1186/1471-2318-13-38}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-95960}, year = {2013}, abstract = {Background Laxatives are among the most widely used over-the-counter medications in the United States but studies examining their potential hazardous side effects are sparse. Associations between laxative use and risk for fractures and change in bone mineral density [BMD] have not previously been investigated. Methods This prospective analysis included 161,808 postmenopausal women (8907 users and 151,497 nonusers of laxatives) enrolled in the WHI Observational Study and Clinical Trials. Women were recruited from October 1, 1993, to December 31, 1998, at 40 clinical centers in the United States and were eligible if they were 50 to 79 years old and were postmenopausal at the time of enrollment. Medication inventories were obtained during in-person interviews at baseline and at the 3-year follow-up visit on everyone. Data on self-reported falls (≥2), fractures (hip and total fractures) were used. BMD was determined at baseline and year 3 at 3 of the 40 clinical centers of the WHI. Results Age-adjusted rates of hip fractures and total fractures, but not for falls were similar between laxative users and non-users regardless of duration of laxative use. The multivariate-adjusted hazard ratios for any laxative use were 1.06 (95\% confidence interval [CI], 1.03-1.10) for falls, 1.02 (95\% CI, 0.85-1.22) for hip fractures and 1.01 (95\% CI, 0.96-1.07) for total fractures. The BMD levels did not statistically differ between laxative users and nonusers at any skeletal site after 3-years intake. Conclusion These findings support a modest association between laxative use and increase in the risk of falls but not for fractures. Its use did not decrease bone mineral density levels in postmenopausal women. Maintaining physical functioning, and providing adequate treatment of comorbidities that predispose individuals for falls should be considered as first measures to avoid potential negative consequences associated with laxative use.}, language = {en} } @phdthesis{Kruempel2013, author = {Kr{\"u}mpel, Christian}, title = {Die Rolle des Multidrug Resistance Associated Protein-1 bei der Tumornekrosefaktor-α vermittelten Apoptose in Endothelzellen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-93681}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Die endotheliale Dysfunktion stellt eine der Hauptursachen f{\"u}r die Entstehung von Atherosklerose an humanen Gef{\"a}ßw{\"a}nden dar und ist somit auch wesentlich an der Entstehung von kardiovaskul{\"a}ren Erkrankungen beteiligt. Das proinflammatorische Zytokin Tumornekrosefaktor-α (TNF-α) gilt als einer der Hauptinduktoren der endothelialen Dysfunktion. Da bei der Endothelzellapoptose unter TNF-α diverse rezeptorvermittelte oxidative Prozesse innerhalb der Zelle ablaufen, sollte im Rahmen dieser Arbeit untersucht werden, inwiefern das Multidrug Resistance Associated Protein-1 (MRP-1) bei diesen oxidativen Prozessen und bei der Modulation der TNF-α-Signalkaskade involviert ist.}, subject = {Tumor-Nekrose-Faktor}, language = {de} } @phdthesis{Thomas2013, author = {Thomas, Nicolai}, title = {Einfluss der EKG-Telemetrie auf die strukturellen Abl{\"a}ufe im Herzinfarktnetz Mainfranken bei der Versorgung von Patienten mit ST-Streckenhebungsmyokardinfarkt (STEMI)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-83769}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Beim akuten Herzinfarkt betr{\"a}gt die 30-Tages-Mortalit{\"a}t immer noch rund 50\%. Die H{\"a}lfte dieser Todesf{\"a}lle geschieht in den ersten 2 Stunden nach Symptombeginn. Zielf{\"u}hrend in der Therapie ist die schnelle Wiederer{\"o}ffnung der verschlossenen Coronararterie. Die Leitlinien der ESC (European Society of Cardiology) empfehlen die prim{\"a}re perkutane Coronarintervention (PPCI) in einem Zeitfenster von weniger als 120 bzw. 90 Minuten nach first medical contact (FMC) durchzuf{\"u}hren. Eine Optimierung der akuten Infarktversorgung erscheint vor diesem Hintergrund dringend erforderlich. Prim{\"a}re Zielgr{\"o}ße des Projekts ist die Verk{\"u}rzung der Contact-to-ballon-Zeit (C2B), also die Zeit zwischen FMC bis zur Ballondilatation. Voraussetzung f{\"u}r schnelle Reaktionszeiten und damit auch f{\"u}r schnelle C2B-Zeiten ist eine sichere und schnelle EKG-Diagnose bereits am pr{\"a}klinischen Einsatzort. Aber, Unsicherheiten bei der STEMI-Diagnostik sind gegenw{\"a}rtig. Um eine Verbesserung der STEMI-Versorgung zu gew{\"a}hrleisten, wurde im Herzinfarktnetz Mainfranken die telemetrische 12-Kanal-EKG-{\"U}bertragung im Pilotversuch eingef{\"u}hrt. In der vorliegenden Arbeit wurde mit Hilfe eines prospektiv erhobenen Patientenregisters untersucht, welchen Einfluss die Etablierung telemetrischer Verfahren in der Akutversorgung von STEMI-Patienten hat. Sowohl die strukturellen Abl{\"a}ufe im Rahmen des Herzinfarktnetzwerkes als auch der klinische Outcome der Patienten wurden untersucht und dokumentiert. Insgesamt erf{\"u}llten {\"u}ber sechs Studienquartale (vom 01.01.2009 bis 30.09.2010) hinweg 310 Patienten die Einschlusskriterien. Die Ergebnisse zeigen, dass durch eine sichere, pr{\"a}klinische EKG-Diagnose mit Hilfe telemetrischer Verfahren, die C2B-Intervalle im Studienzeitraum signifikant reduziert wurden. Auch die innerklinische Behandlung wurde merklich beschleunigt. Zusammenfassend k{\"o}nnen mit Hilfe der telemetrischen EKG-{\"U}bertragung vier wesentliche Punkte verbessert werden. 1. die sichere Diagnosestellung des STEMI; 2. der gezielte Prim{\"a}rtransport in das n{\"a}chstgelegene, geeignete Interventionszentrum; 3. das organsierte Bypassing der n{\"a}chstgelegenen Nicht-Interventionsklinik und somit die Vermeidung von Sekund{\"a}rtransporten; 4. das Bypassing der Notaufnahme und der Intensivstation der Interventionsklinik und somit die Direkt{\"u}bergabe im HKL.}, subject = {Herzinfarkt}, language = {de} } @phdthesis{Devine2013, author = {Devine, Eric}, title = {Increased removal of protein bound uremic toxins through reversible modification of the ionic strength during hemodiafiltration}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-83583}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {A large number of metabolic waste products accumulate in the blood of patients with renal failure. Since these solutes have deleterious effects on the biological functions, they are called uremic toxins and have been classified in three groups: 1) small water soluble solutes (MW < 500 Da), 2) small solutes with known protein binding (MW < 500 Da), and 3) middle molecules (500 Da < MW < 60 kDa). Protein bound uremic toxins are poorly removed by conventional hemodialysis treatments because of their high protein binding and high distribution volume. The prototypical protein bound uremic toxins indoxyl sulfate (IS) and p-cresyl sulfate (pCS) are associated with the progression of chronic kidney disease, cardiovascular outcomes, and mortality of patients on maintenance hemodialysis. Furthermore, these two compounds are bound to albumin, the main plasma protein, via electrostatic and/or Van-der-Waals forces. The aim of the present thesis was to develop a dialysis strategy, based on the reversible modification of the ionic strength in the blood stream by increasing the sodium chloride (NaCl) concentration, in order to enhance the removal of protein bound substances, such as IS and pCS, with the ultimate goal to improve clinical patient outcomes. Enhancing the NaCl concentration ([NaCl]) in both human normal and uremic plasma was efficient to reduce the protein bound fraction of both IS and pCS by reducing their binding affinity to albumin. Increasing the ionic strength was feasible during modified pre-dilution hemodiafiltration (HDF) by increasing the [NaCl] in the substitution fluid. The NaCl excess was adequately removed within the hemodialyzer. This method was effective to increase the removal rate of both protein bound uremic toxins. Its ex vivo hemocompatibility, however, was limited by the osmotic shock induced by the high [NaCl] in the substituate. Therefore, modified pre-dilution HDF was further iterated by introducing a second serial cartridge, named the serial dialyzers (SDial) setup. This setting was validated for feasibility, hemocompatibility, and toxin removal efficiency. A better hemocompatibility at similar efficacy was obtained with the SDial setup compared with the modified pre-dilution HDF. Both methods were finally tested in an animal sheep model of dialysis to verify biocompatibility. Low hemolysis and no activation of both the complement and the coagulation systems were observed when increasing the [NaCl] in blood up to 0.45 and 0.60 M with the modified pre-dilution HDF and the SDial setup, respectively. In conclusion, the two dialysis methods developed to transitory enhance the ionic strength in blood demonstrated adequate biocompatibility and improved the removal of protein bound uremic toxins by decreasing their protein bound fraction. The concepts require follow-on clinical trials to assess their in vivo efficacy and their impact on long-term clinical outcomes.}, subject = {H{\"a}modiafiltration}, language = {en} } @phdthesis{Kaempf2013, author = {K{\"a}mpf, Tanja}, title = {Definition eines klinisch relevanten Morbus Fabry mit Hilfe des Biomarkers Lyso Gb3 bei Patienten mit einer alpha- Galaktosidase Mutation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-77819}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Der Morbus Fabry ist eine sehr heterogenetische und heteroph{\"a}notypische Krankheit. Ursache der Erkrankung liegt in der Mutation des alpha- Galaktosidase Gens. Es kommt zur Akkumulation von Glykosphingolipiden. Man kann den klassischen Typ von mehreren Varianten unterscheiden. Es konnte bisher noch keine Genotyp- Ph{\"a}notyp Relation hergestellt werden. In unsere Studie wurden 124 Fabry Patienten eingeschlossen. Vier klinische Dom{\"a}nen wurden beurteilt (Herz, Nieren, Nervensystem, Fabry-Symptome). Daneben wurden genetische Analysen und Labortests (inklusive Lyso Gb3) durchgef{\"u}hrt. Die Studie besitzt einen zweiteiligen Aufbau: in die Evaluationsstudie wurden alle bisher bekannten Mutationen eingeschlossen, w{\"a}hrend die bisher unbekannten Mutationen der Validierungsstudie zugeteilt wurden. Es konnte gezeigt werden, dass mithilfe des Biomarkers Lyso Gb3 die Schwere der Erkrankung vorausgesagt werden kann (insbesondere bei Frauen) und die Diagnostik erleichtert werden kann. Eine bisher unbekannte Mutation kann jetzt viel besser eingeordnet werden, da man mithilfe des Biomarkers Lyso Gb3 zwischen atypischer und klassischer Variante unterscheiden kann und man durch den Biomarker die Krankheitskapazit{\"a}t einer Mutation beurteilen kann.}, subject = {Fabry-Krankheit}, language = {de} }