TY - THES
A1 - Weigand, Isabel
T1 - Consequences of Protein Kinase A mutations in adrenocortical cells and tumours
T1 - Auswirkungen von Proteinkinase A Mutationen in Zellen und Tumoren der Nebenniere
N2 - Adrenal Cushing’s Syndrome (CS) is a rare but life-threatening disease and therefore it is of great importance to understand the pathogenesis leading to adrenal CS. It is well accepted that Protein Kinase A (PKA) signalling mediates steroid secretion in adrenocortical cells. PKA is an inactive heterotetramer, consisting of two catalytic and two regulatory subunits. Upon cAMP binding to the regulatory subunits, the catalytic subunits are released and are able to phosphorylate their target proteins. Recently, activating somatic mutations affecting the catalytic subunit a of PKA have been identified in a sub-population of cortisol-producing adenomas (CPAs) associated with overt CS. Interestingly, the PKA regulatory subunit IIb has long been known to have significantly lower protein levels in a sub-group of CPAs compared to other adrenocortical tumours. Yet, it is unknown, why these CPAs lack the regulatory subunit IIb, neither are any functional consequences nor are the underlying regulation mechanisms leading to reduced RIIb levels known. The results obtained in this thesis show a clear connection between Ca mutations and reduced RIIb protein levels in CPAs but not in other adrenocortical tumours. Furthermore, a specific pattern of PKA subunit expression in the different zones of the normal adrenal gland is demonstrated. In addition, a Ca L206R mutation-mediated degradation of RIIb was observed in adrenocortical cells in vitro. RIIb degradation was found to be mediated by caspases and by performing mutagenesis experiments of the regulatory subunits IIb and Ia, S114 phosphorylation of RIIb was identified to make RIIb susceptible for degradation. LC-MS/MS revealed RIIb interaction partners to differ in the presence of either Ca WT and Ca L206R. These newly identified interaction partners are possibly involved in targeting RIIb to subcellular compartments or bringing it into spatial proximity of degrading enzymes. Furthermore, reducing RIIb protein levels in an in vitro system were shown to correlate with increased cortisol secretion also in the absence of PRKACA mutations. The inhibiting role of RIIb in cortisol secretion demonstrates a new function of this regulatory PKA subunit, improving the understanding of the complex regulation of PKA as key regulator in many cells.
N2 - Das adrenale Cushing Syndrom, ausgelöst durch ein Kortisol-sekretierendes Nebennierenadenom (CPA), ist eine potentiell letale Erkrankung mit einer geringen Inzidenz. Schon lange ist bekannt, dass der Proteinkinase A (PKA)-Signalweg maßgeblich die Sekretion von Steroidhormonen in der Nebenniere reguliert. In ihrer inaktiven Form ist die PKA ein Heterotetramer aus zwei katalytischen und zwei regulatorischen Untereinheiten, welches über die Bindung des second messengers cAMP und die daraus resultierende Konformationsänderung aktiviert wird. Kürzlich wurden in etwa 40 % der CPAs, somatische Mutationen in der katalytischen Untereinheit a (Ca) der PKA identifiziert. Diese Mutation verhindert die Bindung der regulatorischen Untereinheiten, was zu einer konstitutiven Aktivierung des PKA-Signalwegs führt. Unabhängig davon war bereits einige Jahre zuvor erkannt worden, dass in einem Teil der CPAs die regulatorische Untereinheit IIb (RIIb) der PKA in geringerem Maße exprimiert wird. Ein Zusammenhang zwischen dieser verringerten Proteinmenge an RIIb und den Mutationen in Ca war bisher nicht bekannt. In dieser Dissertation konnte gezeigt werden, dass zwischen den Mutationen in Ca und der verringerten Proteinmenge von RIIb in CPAs, jedoch nicht in anderen Tumorentitäten der Nebenniere, ein klarer Zusammenhang besteht. Darüber hinaus wurde gezeigt, dass auch die Zonen der normalen Nebenniere ein spezifisches Muster der Proteinkinase A Untereinheiten exprimieren. Zusätzlich konnten in in vitro Versuchen Caspasen identifiziert werden, die maßgeblich am Abbau von RIIb beteiligt sind. Durch Mutagenese-Experimente und den Austausch der Inhibitory-Sequenzen der regulatorischen Untereinheiten RIa und RIIb, konnte die Phosphorylierung von Ser114 an RIIb als essentiell für den Abbau identifiziert werden. Darüber hinaus wurden mittels LC-MS/MS neue RIIb Interaktionspartner in Zellen der Nebennierenrinde identifiziert, die sich in der An-oder Abwesenheit der Ca L206R Mutante unterscheiden. Ferner konnte für RIIb eine inhibierende Rolle, speziell in der Kortisol-Sekretion von Nebennierenrindenzellen, gezeigt werden. Dies stellt eine bislang unbekannte Funktion von RIIb dar, die das Verständnis der komplexen Regulierung von PKA als Schlüsselregulator in vielen Zellen verbessert.
KW - Cushing-Syndrom
KW - protein kinase a
KW - cushing's syndrome
KW - tumour
KW - signalling
KW - adrenal gland
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160646
ER -
TY - THES
A1 - Chifu, Irina
T1 - Expression und prognostische Bedeutung der Chemokinrezeptoren CXCR4 und CXCR7 bei malignen Nebennierentumoren
T1 - Prognostic Relevance of the Chemokine Receptors CXCR4 and CXCR7 in Malignant Adrenal Tumors
N2 - Zusammenfassung:
Unsere Arbeit bestätigt die aus kleineren Studien bekannte hohe Expression der Chemokinrezeptoren CXCR4 und CXCR7 in der normalen Nebenniere und in der Mehrheit der Nebennierenkarzinome. Das auf mRNA Ebene bestätigte Vorkommen beider Chemokinrezeptoren im gesunden Nebennierengewebe deutet auf eine überwiegend für die normale Nebennierenphysiologie wichtige Rolle dieser Chemokinrezeptoren hin. Eine eventuell dennoch bestehende pathophysiologische Relevanz der Rezeptoren wurde ergänzend überprüft und ergab keinen signifikanten Einfluss auf die Prognose des Nebennierenkarzinoms.
N2 - Summary:
Our study describes the expression profile and prognostic relevance of the chemokine receptors CXCR4 and CXCR7 in 187 clinically annotated adrenocortical carcinoma specimens. The main findings of our analysis are a strong expression of both chemokine receptors in the majority of primary tumors and metastases. In contrast to other malignancies we did not observe a relevant prognostic impact of CXCR4 and CXCR7 expression. We assume that this observation may be associated with the high constitutive expression of both receptors also in the normal adrenal cortex and their putative role in adrenal homeostasis.
KW - Nebennierenrindencarcinom
KW - Chemokinrezeptor
KW - CXCR4
KW - CXCR7
KW - Prognose
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-217225
ER -
TY - THES
A1 - Helf, Daniel
T1 - Beschreibung des Bowditch-Effektes in Abhängigkeit der Ausprägung einer Herzinsuffizienz am Tiermodell
T1 - Characterization of the Bowditch effect according to the developement of congestive heart failure in an animal model
N2 - Bei den primär herzgesunden Tieren wurde durch Frequenz-Überstimulation mit Hilfe eines implantierten biventrikulären Herzschrittmachers eine chronische Herzinsuffizienz induziert. Im Rahmen der Verlaufsbeobachtungen wurde in-vivo die Druckanstiegsgeschwindigkeit dP/dtmax, der enddiastolische sowie endsystolische Druck durch einen implantierten Drucksensor gemessen. Anhand der gemessen dP/dtmax-, EDP- und ESP-Werte konnte der Bowditcheffekt dargestellt werden. Mit Ausprägung einer chronischen Herzinsuffizienz fiel dieser im Verlauf deutlich geringer aus, blieb aber stets nachweisbar.
N2 - Congestive heart failure was induced in initially healthy adult sheep by frequency overstimulation. On the basis of velocity of pressure rise (dP/dtmax), endsystolic pressure (ESP) and enddiastolic pressure (EDP) Bowditch effect was demonstrated. Along with the developement of a congestive heart failure Bowditch effect decreased but was throughout detectable.
KW - Treppenphänomen
KW - Herzinsuffizienz
KW - Bowditcheffekt
KW - Tiermodell
KW - Frequenzüberstimulation
KW - Congestiv Heart Failure
KW - Force-frequency relation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-219181
ER -
TY - THES
A1 - Zapp, Benedikt Alexander
T1 - Einfluss der Nikotinamid N-Methyltransferase-Aktivität auf die Glukoseaufnahmerate weißer und brauner Adipozyten
T1 - Influence of nicotinamide-N-methyltransferase activity on glucose uptake rate in white and brown adipocytes
N2 - Die Nikotinamid N-Methyltransferase (NNMT) wurde als wichtiger Regulator des Energiemetabolismus in Fettzellen beschrieben. So bewahrt ein NNMT Knock-down Mäuse vor einer nahrungsinduzierten Adipositas und bei reduzierter NNMT-Expression in weißen 3T3-L1 Adipozyten zeigen diese einen erhöhten zellulären Sauerstoffverbrauch.
Für den Adipozytenstoffwechsel ist die insulinstimulierte Glukoseaufnahme wesentlich. Um den Einfluss eines NNMT-Knock-downs auf diese zu untersuchen wurde unter Nutzung der Substratspezifitäten des prokaryotischen und eukaryotischen Isoenzyms der Glukose-6-phosphat-Dehydrogenase ein enzymatisch-photometrischer Assay zur Messung der Glukoseaufnahmerate in adhärenten weißen 3T3-L1 und braunen Adipozytenkulturen entwickelt.
Mit lentiviraler Transduktion wurde in den Adipozytenkulturen ein persistenter NNMT-Knock-down induziert. Die NNMT-Aktivität wurde mit einem fluoreszenzbasierten Assay gemessen und die Glukoseaufnahmerate in deren Abhängigkeit bestimmt.
Die Reduktion der NNMT-Aktivität verminderte die Glukoseaufnahmerate der 3T3-L1 Adipozyten sowohl basal, wie auch unter Insulinstimulation. Braune Adipozyten hingegen zeigten bei verringerter NNMT-Aktivität eine erhöhte insulinstimulierte Glukoseaufnahmerate, aber keinen Unterschied der basalen Glukoseaufnahmerate.
Dieser differenzielle Einfluss auf die Glukoseaufnahme weißer und brauner Adipozyten stärkt die wichtige Rolle der NNMT, die ihr zur Regulation des Fettzellstoffwechsels zugeschrieben wird und enthüllt erstmals eine direkte Wirkung auf braune Adipozyten.
N2 - Nicotinamide-N-methyltransferase (NNMT) was characterized as an important regulator of energy metabolism in adipocytes. NNMT knock-down in mice protected from diet induced obesity and white 3T3-L1 adipocytes showed elevated cellular oxygen consumption at reduced NNMT expression.
Insulin stimulated glucose uptake is essential for adipocyte metabolism. To analyze the influence of NNMT knock-down on insulin stimulated glucose uptake an enzymatic-photometric assay for cultured adherent white 3T3-L1 and brown adipocytes was developed, utilizing substrate specificities of prokaryotic and eukaryotic isoenzymes of glucose-6-phosphate dehydrogenase.
By lentiviral transduction a persistent NNMT knock-down was induced in both adipocyte cultures. In dependence of NNMT activity, measured by a fluorescence-based assay, glucose uptake rate was determined.
Reduction of NNMT activity diminished basal and insulin stimulated glucose uptake rate of 3T3-L1 adipocytes. In contrast brown adipocytes showed elevated insulin stimulated glucose uptake rate at reduced NNMT activity, but no changes in basal glucose uptake rate.
The importance of NNMT in regulating adipocyte metabolism is supported by the finding of a differential influence on glucose uptake of white and brown adipocytes. For the first time a straight impact of NNMT on brown adipocytes is revealed.
KW - Weiße Fettzelle
KW - Braune Fettzelle
KW - Glucosestoffwechsel
KW - Glucosephosphatdehydrogenase
KW - Fettsucht
KW - Nicotinamid-N-Methyltransferase
KW - Glukoseaufnahme
KW - Adipositas
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-219529
ER -
TY - THES
A1 - Carl, Salome
T1 - Anatomische Besonderheiten der Mundhöhle und der Kopf-Halsregion bei Morbus Fabry Patienten
T1 - Anatomical anomalies of the oral cavity and head-neck region in patients with Fabry disease
N2 - Morbus Fabry betrifft als lysosomale Speicherkrankheit viele Organsysteme durch die Ablagerung von Gb3 in verschiedenen Geweben. Besonders durch die Beteiligung von Nieren und Herz, wird die Lebenszeit von den Patienten häufig verkürzt. Eine Beschreibung konkreter klinischer Symptome, welche auch durch Allgemeinmediziner oder Zahnärzte erkannt werden könnten, könnte eine frühzeitigere Diagnose und damit frühzeitige Therapie ermöglichen. Besonders extraorale gesichtsspezifische Merkmale können von verschiedensten Gruppen von Ärzten erkannt werden.
Die extraorale Auswertung zeigte, wie in der Literatur beschrieben, das Vorkommen von periorbitaler Fülle, prominente Arcus superciliaris, eine kürzere und bullösere Nase. Die Auffälligkeiten waren besonders bei den Männern zu beobachten.
Die intraorale Auswertung wurde in dentale Auffälligkeiten und Ereignisse des Hart- und Weichgewebes eingeteilt. Bei den dentalen Ereignissen zeigte sich eine Diskrepanz zwischen der Kiefergröße und dem Zahnmaterial. So neigte das Patientenkollektiv eher zu einem Breitkiefer, was eine Erklärung für die multiplen Lücken im Frontzahnbereich der Patienten darstellt. An der Mundschleimhaut und perioral konnten vermehrt Angiokeratome und Teleangiektasien festgestellt werden, sowie das vermehrte Vorkommen von Exostosen. Speziell die Zunge der Patienten zeigte auch Auffälligkeiten in Form von einer subjektiven Makroglossie, einer Furchenzunge und Veränderungen der Papillen.
Die Auffälligkeiten in der Mundhöhle und im Kopf-Hals Bereich der Morbus Fabry Patienten sind, wie der Literatur beschrieben, vorhanden, jedoch stellen sie keine Schlüsselrolle in der Diagnose dar, da sie in allen Bereichen nur leichte Abweichungen oder Auffälligkeiten zeigen, welche nicht immer Auftreten und daher schwer zu diagnostizieren sind.
N2 - Fabry disease is a lysosomal storage disease which affects various organ systems through the deposition of Gb3 in different tissues. Especially due to the involvement of heart and kidneys, the patients’ life expectation is often reduced. A description of clinical symptoms which could be identified by general practitioners or dentists, could lead to an earlier diagnosis and therapy for patients. Particularly extraoral facial abnormalities could be recognized by different groups of physicians.
The extraoral evaluation, as outlined in literature, showed the appearance of periorbital fullness, prominent supra-orbital ridges, a shorter and more bulbous nose. These abnormalities were most prominent among men.
The intraoral analysis was divided into dental abnormalities as well as features of the oral cavity’s hard and soft tissue. It displayed a discrepancy between the jaw- and teeth size which explains the occurrence of multiple diastematas in the anterior tooth region. A higher frequency of angiokeratomas and teleangiectasies was found on the oral mucosa and perioral, as well as an increased incidence of exostoses. In particular, the patients’ tongues also showed abnormalities in the form of a subjective makroglossia, fissuring of tongue and changes in the papillae.
The anomalies of the oral cavity and the head-neck region of Fabry patients are, as described in literature, present. However, they do not take a key role in the diagnosis of Fabry disease itself as they only show slight divergences or abnormalities, which do not necessarily always occur and therefore pose difficult to be diagnosed.
KW - Fabry-Krankheit
KW - Lysosomale Speicherkrankheit
KW - Morbus Fabry
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-220184
ER -
TY - THES
A1 - Mages, Christine Maria Gabriele
T1 - Effekt von Mitofusin 2 Defizienz auf die IP\(_3\)-induzierte mitochondriale Calciumregulation in Kardiomyozyten
T1 - Effect of mitofusin 2 deficiency on the IP\(_3\)-induced mitochondrial calcium regulation in cardiomyocytes
N2 - Das Herz ist physiologisch auf einen fein regulierten und ausgeglichenen bioenergetischen Energiehaushalt angewiesen, um auf akute Belastungssituationen adäquat reagieren zu können und oxidativen Stress zu vermeiden. Ca2+ reguliert zentral sowohl die zyklischen Kontraktions-/Relaxationsprozesse (ECC) als auch unmittelbar den mitochondrialen Metabolismus. Der ECC liegt in den Kardiomyozyten die Ca2+- Freisetzung durch die RyR2 zu Grunde; die IP3 Rezeptoren des sarkoplasmatischen Retikulums (SR) führen davon unabhängig zu einer Ca2+ Freisetzung aus dem SR. Diese IP3R vermittelten Signale werden in den räumlich nahe gelegenen Mitochondrien zum Teil über den mRyR1 in die mitochondriale Matrix aufgenommen und stimulieren dort langfristig die oxidative Phosphorylierung und den Erhalt der antioxidativen Kapazität. Die enge räumliche Nähe zwischen SR und Mitochondrien wird durch Strukturproteine wie Mitofusin 2 (Mfn2) ergänzt, die das SR mit der äußeren Mitochondrienmembran koppeln und so die Ca2+-Interaktion beeinflussen. Ziel der Arbeit war, den Effekt von Mfn2 Defizienz auf die IP3 induzierte mitochondriale Ca2+-Regulation in Kardiomyozyten zu evaluieren. Dazu erfolgten Fluoreszenzfärbungen an adulten isolierten Ventrikelkardiomyozyten kardiospezifischer Mfn2 Knock-Out (KO) Mäusen bzw. deren wildtypischen Geschwistertieren (WT). Erhobene Parameter umfassten das mitochondriale Ca2+, das mitochondriale Membranpotenzial, die mitochondriale Superoxidbildung und mitochondriale ATP-Gehalt. Die Ergebnisse bestätigten eine Signalachse, bei der die Stimulation von isolierten murinen Kardiomyozyten mit dem IP3 Agonisten ET-1 zu einer mitochondrialen Ca2+ Aufnahme führte, dem Erhalt des mitochondrialen Membranpotenzials diente und der ATP Gehalt stiegt. Bei induzierter kardiospezifischer Ablation von Mfn2 geht diese SR-mitochondriale Interaktion verloren, und es entstand ein energetisches Defizit sowie eine verminderte Superoxidbildung. Bei beta-adrenerger Stimulation mit Isoproterenol (ISO) resultierte in WT zwar eine mitochondriale Ca2+-Aufnahme, allerdings ein Abfall des ATP-Gehaltes. In den Mfn2 defizienten Kardiomyozyten zeigte sich eine Steigerung des ATP-Gehaltes auch auf beta-adrenerge Stimulation, die einen energetischen Kompensationsmechanismus in den Mfn2 KO Tieren vermuten lässt. Dies identifiziert Mfn2 als kritische Strukturkomponente für die basale bioenergetische Adaptation der durch IP3R-mRyR1 vermittelten Signalachse unter physiologischen Bedingungen.
N2 - Under physiological conditions the heart needs a finely tuned bioenergetic adaptation system to adequately match sudden changes in the workload and to avoid oxidative stress. Ca2+ regulates the excitation-contraction-coupling (ECC) as well as the mitochondrial metabolism. The ECC is based on the release of Ca2+ via the RyR2 while the IP3 receptor (IP3R) releases Ca2+ independently from the sarcoplasmatic reticulum (SR). The signals from the latter are taken up by the surrounding mitochondria via the mRyR1 channel to stimulate both the basal oxidative phosphorylation and the antioxidative capacity. The close functional relationship between mitochondria and SR is affected by membrane-coupling proteins like mitofusin 2 (Mfn2) that may influence the Ca2+ transmission. This work aimed at evaluating the effect of Mfn2 deficiency on the IP3-induced mitochondrial calcium regulation in cardiomyocytes. Mitochondrial Ca2+ uptake, membrane potential, redox state and ATP generation were monitored in isolated ventricular cardiomyocytes of cardio-specific mitofusin 2 Knock-out (KO) mice and their wildtype littermates (WT) via fluorescent staining using laser scanning confocal microscopy. The results show that stimulation with the IP3 agonist ET-1 led to mitochondrial calcium uptake, ATP generation and maintained mitochondrial membrane potential. The cardio-specific loss of the tethering protein Mfn2 resulted in an energetic deficit and decreased levels of superoxide. Beta adrenergic receptor activation with isoproterenol (ISO) in WT resulted in a mitochondrial calcium uptake but decreased ATP content, while leading in Mfn2 KO cardiomyocyte to increased levels of ATP, pointing probably towards an energetic compensatory mechanism. Taken together these results propose Mfn2 as a critical structural component that affects under physiological conditions the privileged SR-mitochondrial metabolic feedback mechanism via IP3R and mRYR1 to maintain normal cardiac function and bioenergetics.
KW - SR/Mitochondriales Feedback
KW - Mitofusin2
KW - IP3-Signaling
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-237966
ER -
TY - THES
A1 - Eckhardt, Carolin
T1 - Sterol O-Acyltransferasen als Zielmoleküle in der Tumortherapie sowie die klinische Relevanz ihrer Expression beim Prostatakarzinom
T1 - Sterol-O-Acyl transferases as target molecules in tumor therapy and the clinical relevance of their expression in prostate cancer
N2 - Sterol O-Acyltransferasen (SOATs) spielen eine zentrale Rolle im Cholesterinstoffwechsel von Zellen, indem sie die Veresterung von freiem Cholesterin und Speicherung in Lipid droplets katalysieren. In Tumorzellen findet häufig eine Aktivierung alternativer Pfade des Energiestoffwechsels, unter anderem des Lipidstoffwechsels statt. Präklinische und klinische Daten unterstützen den Mechanismus der SOAT-Inhibierung als Therapiekonzept für bestimmte Tumore. Eine genaue Kenntnis sowohl dieser Inhibitoren als auch der Expression des Zielmoleküls ist Voraussetzung für eine klinische Anwendung.
Im ersten Teil dieser Arbeit wurde ein in-vitro SOAT-Aktivitätsassay etabliert und auf Grundlage dessen ein Vergleich der mittleren Hemmstärken ausgewählter SOAT-Inhibitoren gezogen. SOAT-transfizierte AD-293 Zellen sowie NCI-H295R Nebennieren-Zellen wurden mit dem fluoreszierenden 22-NBD-Cholesterin sowie den SOAT-Inhibitoren inkubiert und die Veresterung des Lipid-Analogons dann zunächst mikroskopisch und anschließend quantitativ mittels chromatographischer Auftrennung untersucht. Mitotane stellte sich mit einer IC50 von 1,3x10⁻⁶ M als schwächster SOAT-Inhibitor dar, gefolgt von Sandoz58-035 (IC50=1,4x10\(^{-8}\) M), ATR101 (IC50=3,1x10\(^{-9}\) M) und schließlich AZD3988 (IC50=8,8x10\(^{-10}\) M).
Im zweiten Teil dieser Arbeit wurde die SOAT-Expression in Prostatektomiepräparaten von Hochrisiko Prostatakarzinom-Patienten mittels Immunhistochemie bestimmt. Eine starke SOAT1 Expression (SOAT H-Score 3) war sowohl in der univariaten als auch in der multivariaten Analyse hoch signifikant mit einem kürzeren biochemisch progressfreien Überleben der Patienten assoziiert unabhängig von etablierten Prognoseparametern [HR für den biochemischen Progress 2,33 (95%KI 1,48-3,68), p<0,001)]. Für SOAT2 war dies erwartungsgemäß nicht der Fall. SOAT1 scheint bei diesem bestimmten Kollektiv einen vielversprechenden Stellenwert als prognostischer Marker zu haben und könnte darüber hinaus zukünftig als Zielmolekül im Rahmen einer individualisierten Therapie des Prostatakarzinoms in Frage kommen.
N2 - Sterol-O-Acyl transferases (SOATs) play a central role in cellular cholesterol metabolism by catalyzing the esterification of free cholesterol and storage in lipid droplets. In tumor cells, activation of alternative pathways of energy metabolism, including lipid metabolism, frequently occurs. Preclinical and clinical data support the mechanism of SOAT inhibition as a therapeutic concept for certain tumors. Accurate knowledge of both these inhibitors and the expression of the target molecule is a prerequisite for clinical application.
In the first part of this work, an in vitro SOAT activity assay was established and a comparison of the mean inhibitory strengths of selected SOAT inhibitors was drawn based on this. SOAT-transfected AD-293 cells as well as NCI-H295R adrenal cells were incubated with the fluorescent 22-NBD cholesterol as well as the SOAT inhibitors, and the esterification of the lipid analogue was then examined first microscopically and then quantitatively by chromatographic separation. Mitotane turned out to be the weakest SOAT inhibitor with an IC50 of 1.3x10⁻⁶ M, followed by Sandoz58-035 (IC50=1.4x10\(^{-8}\) M), ATR101 (IC50=3.1x10\(^{-9}\) M) and finally AZD3988 (IC50=8.8x10\(^{-10}\) M).
In the second part of this work, SOAT expression in prostatectomy specimens from high-risk prostate cancer patients was determined by immunohistochemistry. Strong SOAT1 expression (SOAT H-score 3) was highly significantly associated with shorter biochemical progression-free survival of patients independent of established prognostic parameters in both univariate and multivariate analysis [HR for biochemical progression 2.33 (95%CI 1.48-3.68), p<0.001)]. As expected, this was not the case for SOAT2. SOAT1 appears to have promising value as a prognostic marker in this particular collective and, moreover, could be considered as a future target in the context of individualized therapy of prostate cancer.
KW - Sterol O-Acyltransferasen
KW - SOAT
KW - Hochrisiko Prostatakarzinom
KW - SOAT Inhibitoren
KW - Sterol-O-Acyl transferases
KW - High risk prostate cancer
KW - Cholesterol metabolism
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-243002
ER -
TY - THES
A1 - Geier, Bettina
T1 - Kernspintomografische Natriumbildgebung in Haut und Muskel
T1 - Magnetic resonance imaging of sodium in skin and muscle
N2 - Die vorliegende Arbeit untersucht den Natriumgehalt verschiedener Kompartimente des Körpers mittels Magnetresonanztomographie (= MRT).
Die Korrelation zwischen erhöhtem Salzkonsum und arterieller Hypertonie ist bereits umfangreich analysiert worden. Für das Verständnis der pathophysiologischen Zustände und deren Regulation, ist eine Quantifizierung von Natriumkonzentrationen in verschiedenen Gewebearten bedeutsam. Die exakte Messung von Natriumkonzentrationen im menschlichen Gewebe ist derzeit experimentell. Im Rahmen der hier vorgelegten Arbeit wurden die Natriumkonzentrationen von Haut und Skelettmuskel mittels 23Na Magnetresonanztomographie (= 23 Na MRT) im menschlichen Körper quantifiziert.
Natriummessungen wurden bei Patienten mit primärem Hyperaldosteronismus (= PHA), bei Patienten mit essentieller Hypertonie (= EH), sowie einer gesunden Kontrollgruppe vorgenommen.
Die Ergebnisse zeigten, dass Haut und Skelettmuskel Speicherorgane für Natrium im menschlichen Körper darstellen. Durch gezielte Therapie waren die Natriumkonzentrationen in beiden Speicherorganen modulierbar
N2 - The present work investigates the sodium content of different compartments of the body by means of magnetic resonance imaging (= MRI).
The correlation between increased salt consumption and arterial hypertension has already been extensively analyzed. For the understanding of pathophysiological states and their regulation, quantification of sodium concentrations in different tissue types is significant. Accurate measurement of sodium concentrations in human tissues is currently experimental. In the work presented here, sodium concentrations of skin and skeletal muscle were quantified using 23Na - magnetic resonance imaging (= 23 Na-MRI) in the human body.
Sodium measurements were made in patients with primary hyperaldosteronism (= PHA), in patients with essential hypertension (= EH), and in a healthy control group.
The results showed that skin and skeletal muscle are storage organs for sodium in the human body. Sodium concentrations in both storage organs could be modulated by targeted therapy.
KW - Natrium-23
KW - Kernspintomografie
KW - Haut
KW - Muskel
KW - MRI
KW - sodium-23
KW - Skin
KW - Muscle
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-249429
ER -
TY - THES
A1 - Ruck [geb. Stelzl], Claudia Michaela
T1 - Ultraschallgesteuerte Perikardpunktion unter Einsatz eines elektromagnetischen Ortungssystems – Entwicklung und experimentelle Validierung
T1 - Ultrasound-guided pericardiocentesis using an electromagnetic tracking system: development and experimental validation
N2 - Perikardpunktionen werden neben diagnostischen Anwendungen vor allem in Notfallsituationen, wie bei einer Perikardtamponade, eingesetzt und können dann lebensrettend sein. Unerfahrene Untersucher stellen hierbei aber einen wesent- lichen Faktor für Komplikationen oder den Behandlungserfolg dar.
Um die Perikardpunktion zu optimieren, wurde im Rahmen einer experimentellen Untersuchung die neue Technik unter Verwendung eines elektromagnetischen Nadel Tracking Systems validiert. Hierzu wurde zunächst ein Modell entwickelt um die Punktionsgenauigkeit des Systems abhängig von seinen Einflussgrößen möglichst exakt beurteilen zu können. Es zeigte sich, dass das Punktionsergebnis von mehreren Faktoren wie Punktionswinkel, -seite, Ultraschallebene, Abstand zum Ziel und Vorhandensein von Metallgegenständen abhängt.
Des Weiteren wurde ein realitätsnahes Perikardpunktionsmodell verwendet. An diesem Modell wurden Perikardergüsse unterschiedlicher Größe simuliert und anschließend Punktionen mit der Nadel durchgeführt. Im BluePhantomTM Modell wurden mithilfe des Nadel Tracking Systems von unerfahrenen Untersuchern Trefferquoten zwischen 80 und 100% erreicht, unabhängig von der Ergussgröße. Anatomisch orientierte Punktionen erreichten hingegen nur Trefferquoten zwischen 11 und 44% bei einer Ergussmenge von 250 ml (bzw. 60-80% bei 450 ml).
Das getestete Nadel Tracking System könnte somit zur Verbesserung der Perikardpunktionen beitragen. Für eine abschließende Bewertung ist eine Validierung der Methode unter klinischen Bedingungen möglich.
N2 - In addition to diagnostic applications, pericardiocentesis is mainly applied in emergency situations, such as a pericardial tamponade, and can then be life-saving. However, inexperienced examiners represent an essential risk factor for complications or the missing success of treatment.
In order to optimize the procedure of pericardiocentesis, we experimentally validated an electromagnetic needle tracking system. For this purpose, we developed a model to assess the puncture accuracy of the system. We identified several factors that affect the accuracy of the system including puncture angle and side, ultrasound plane, distance to the target, and presence of metal objects.
Furthermore, we used the BluePhantomTM pericardiocentesis model, which provides a realistic clinical scenario. In this model, we simulated pericardial effusions of different sizes and evaluated success rates for different pericardiocentesis techniques. The success rates for the needle tracking system ranged between 80 and 100%, which were achieved by inexperienced examiners regardless of the effusion size. In contrast, anatomically oriented punctures led to success rates between 11 and 44% with an effusion size of 250 ml (or 60-80% for 450 ml).
Overall, the tested needle tracking system could thus contribute to the improvement of pericardiocentesis in clinical prectice. For a final evaluation, a validation of the method under clinical conditions is possible.
KW - Perikard
KW - Pericardium
KW - Ultraschallgeführte Biopsie
KW - Ultraschallgesteuert
KW - Perikardpunktion
KW - Perikardiozentese
KW - elektromagnetisches Trackingsystem
KW - pericardiocentesis
KW - ultrasound guided
KW - electromagnetic tracking system
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-247543
ER -
TY - THES
A1 - Simon, Rosa-Sophie
T1 - Hypoglykämische Episoden bei hämodialysepflichtigen Patienten mit Typ-2-Diabetes-mellitus - Ein Vergleich von Therapieansätzen
T1 - Hypoglycaemic episodes in patients with type-2-diabetes-mellitus depending on dialyses - a comparison of therapeutic strategies
N2 - Im Rahmen der EFSD Studie erfolgt die Aufzeichnung von Blutzuckerdaten und Interpretation. Dabei erfolgte die Unterteilung in vier Therapiegruppen: Patienten mit reiner Insulintherapie, mit OAD-Therapie, mit einer Kombination aus Insulin und OAD-Therapie sowie mit einer diätetischen Therapie. Unterschieden wurde innerhalb der Therapiegruppen zwischen Dialysezeiten und dialysefreier Zeit. Die definierten Hypoglykämieintervalle (Hypoglykämie 51 bis 70 mg/dl, schwere Hypoglykämie ≤ 50 mg/dl) wurden in den verschiedenen Gruppen und Zeiten ausgewertet.
Insgesamt kam es während der Gesamtaufzeichnungszeit zu einem prozentual geringen zeitlichen Auftreten von Hypoglykämien sowohl während der Dialysezeit als auch während der dialysefreien Zeit. Die Therapiegruppen unterschieden sich deutlich in ihrer Gruppengröße. Durch die entsprechenden Vorerkrankungen besteht bereits ein deutlich erhöhtes Hypoglykämierisiko und damit erhöhtes Mortalitätsrisiko bei der untersuchten Patientenkohorte. Im Vergleich aller vier unterschiedenen Therapiegruppen ergab sich keine statistische Signifikanz bezüglich eines erhöhten Hypoglykämierisikos bei einer Therapiegruppe. Weder zeigte sich eine Signifikanz während der Dialyse noch in der dialysefreien Zeit. Auch in der Auswertung der HbA1c-Werte besteht eine breite Verteilung, sodass keine zuverlässige Aussage über eine Hypoglykämieneigung abgeleitet werden kann.
N2 - In the EFSD Studie blood glucose was was recorded and evaluated. Therefore, four groups were defined: stand-alone insulin therapy, therapy with oral-antidiabetic drugs, combined insulin and OAD therapy and dietetic therapy. Within these four groups, the time during dialysis and off-dialysis was observed. The times of defined intervals of hypoglycaemia (light hypoglycaemia 51 – 70 mg/dl and severe hypoglycaemia <50 mg/dl) were recorded and evaluated.
Within the whole measuring time, hypoglycaemia occurred only in a very low percentage during dialysis and off-dialysis time. The groups clearly differed in size. Because of pre-existing conditions, the risk for hypoglycaemia and the mortality risk was increased. The comparison within these four groups showed no statistically significant difference regarding hypoglycaemic episodes. This includes dialysis and off-dialysis time. The evaluation of Hba1c showed a wide range, so a risk for hypoglycaemia was not evaluable.
KW - Diabetes mellitus Typ 2
KW - Hämodialyse
KW - Typ-2-Diabetes-mellitus
KW - Hämodialyse
KW - Hypoglykämie
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248741
ER -
TY - THES
A1 - von der Heide, Sina
T1 - Zusammenhänge zwischen der Immunantwort und den myokardialen Heilungsprozessen (Remodeling) bei Patienten nach akutem transmuralen Erstinfarkt bzw. nach akuter Myokarditis
T1 - Correlations between the immune response and the myocardial healing process (remodeling) regarding patients suffering from acute transmural first myocardial infarction respectively acute myocarditis
N2 - Die häufigste Form der Herzinsuffizienz in Deutschland ist die dilatative Kardiomyopathie, wobei bei ca. 6/100.000 Einwohnern pro Jahr keine eindeutige Ursache erkennbar ist und somit eine idiopathische DCM diagnostiziert wird. Ein Faktor zur Entstehung einer idiopathischen DCM könnten Autoantikörper gegen den β1-adrenergen Rezeptor sein. Bei ca. 30% der Patienten, die an einer DCM (Äquivalent in der ETiCS-Studie: erste akute Myokarditis = AMitis) leiden, sowie bei ca. 13% der Patienten, die an einer ischämischen Kardiomyopathie (Äquivalent in der ETiCS-Studie: erster akuter Myokardinfarkt = FAMI) leiden, konnten in älteren Arbeiten β1-AAk nachgewiesen werden. Im Rahmen der ETiCS-Studie erfolgte erstmals eine prospektive Beobachtung entsprechender Patientenkollektive über 12 Monate mit Blutentnahme und klinischen Kontrollen zum Zeitpunkt 0 Monate (=Baseline), 2-3 Monate (Follow-Up 1), 6 Monate (FUP2) und 12 Monate (FUP3). Zu diesen Zeitpunkten wurden anhand der gewonnenen Blutproben der β1-AAk-Status sowie die immunologischen Marker der FAMI- und AMitis-Patienten bestimmt und mit der kardialen LV-Pumpfunktion korreliert.
Zentrales Thema dieser Arbeit war es, Zusammenhänge zwischen der β1-AAk-Ausbildung in Abhängigkeit von individuellen Zytokinprofilen und der Entwicklung der LV-Pumpfunktion nach dem jeweiligen kardialen Ereignis zu untersuchen, wobei FAMI- und AMitis-Patienten miteinander verglichen wurden. Darüber hinaus wurde auch der Einfluss der CTLA-4-Haplotypen, also die „genetische“ Suszeptibilität Autoantikörper zu entwickeln, untersucht.
Während bei FAMI-Patienten die Entwicklung von β1-AAk keinen Einfluss auf den Verlauf der LV-Pumpfunktion zu haben scheint, wird diese bei AMitis-Patienten durch hochaffine β1-AAk im Verlauf stark beeinträchtigt.
Bei FAMI-Patienten konnte nach einer größeren Herzschädigung (CK-Werte >1000 U/l) eine schlechtere Pumpfunktion im Vergleich zu kleineren Myokardinfarkten (CK-Werte <1000 U/l) nachgewiesen werden, unabhängig von β1-AAk-Status. Für die Prognose und die Erholung der LV-Pumpfunktion scheint bei FAMI-Patienten folglich die Infarktgröße, aber nicht die Entwicklung von β1-AAk wichtig zu sein.
Hinsichtlich der unterschiedlichen Zytokinprofile bei FAMI- und AMitis-Patienten, die hochaffine β1-AAk entwickeln, scheinen bestimmte Zytokine die Induktion einer kardialen Autoimmunität zu begünstigen, während andere Zytokine wohl eher protektive immunologische Reaktionen in Gang setzen: Die proinflammatorischen Zytokine IL-1β, IL-2, IL-7, IL-12, IL-17, GM-CSF, MIP-1α und IFN-γ waren bei β1-AAk-positiven AMitis-Patienten statistisch signifikant erhöht. Protektive Effekte könnten dagegen von den antiinflammatorischen Zytokinen IL-1RA, IL-10 und IL-13 ausgehen, deren Serumspiegel bei FAMI- gegenüber AMitis-Patienten im Vergleich erhöht waren.
Beim direkten Vergleich von AMitis-Patienten mit hochaffinen β1-AAk und solchen ohne β1-AAk, zeigten sich bei Patienten mit hochaffinen β1-AAk höhere Konzentrationen an IL-1β, IL-2, IL-6, IL-7, IL-12, IL-17, GM-CSF, MIP-1α und TNF-α. Bei Patienten ohne Autoantikörper waren demgegenüber die Spiegel von IL-1RA, IL-10 und IL-13 erhöht, was zu einer besseren Erholung der LV-Pumpfunktion führte.
Nach genetischer Typisierung der CTLA-4-Haplotypen (Polymorphismen SNP +49G/A und SNP CT60A/G) fand sich bei Patienten mit dem Allel G/G ein höheres Risiko β1-AAk zu entwickeln, während das Allel A/A jeweils mit einem geringeren Risiko kardiale Autoantikörper zu entwickeln assoziiert war und somit protektiv gegen Autoimmunphänomene wirken könnte.
N2 - Autoantibodies directed against the beta1-receptor can be found within 30% of patients suffering from acute myocarditis and 13% of patients suffering from acute myocardial infarction. These autoantibodies cause a higher risk of heart failure and can lead to dilated cardiomyopathy. The levels of certain proinflammatory cytokines are expressed significantly higher by patients with these autoantibodies, whereas higher levels of antiinflammatory cytokines can be found within patients that didn't develop beta1-autoantibodies. This suggests that proinflammatory cytokines can lead to autoimmunity and impair the prognosis of the patients. Antiinflammatory cytokines on the other hand play a protective role against the development of beta1-autoantibodies.
Analyzing the different allels of the SNPs +49G/A and CT60A/G, the allel G/G is bearing a higher risk of developing beta1-autoantibodies while the allels A/A and A/G may play a protective role.
KW - Immunreaktion
KW - Herzinfarkt
KW - Myokarditis
KW - Immunantwort
KW - Myokardinfarkt
KW - Autoantikörper
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248790
ER -
TY - THES
A1 - Lau, Kolja
T1 - Diastolische Herzfunktion und ihre Vorhersagekraft auf das Langzeitüberleben bei HerzinsuffizienzpatientInnen mit mittelgradiger oder reduzierter linksventrikulärer Ejektionsfraktion
T1 - Impact of diastolic dysfunction on outcome in heart failure patients with mid-range or reduced ejection fraction
N2 - Diese retrospektive Auswertung von PatientInnendaten der kardiologischen Ambulanz des Universitätsklinikums Würzburg konnte zeigen, dass die Bestimmung der diastolischen Dysfunktion prognostisch relevante Informationen enthält. Das Studienkollektiv wurde anhand der gemessenen Ejektionsfraktion in die zwei Untersuchungsgruppen HFrEF und HFmrEF eingeteilt. Diese zwei Untersuchungsgruppen wurden anhand ihrer klinisch und echokardiographisch bestimmten Charakteristika verglichen. Anschließend wurden drei diastolische Parameter (E/e’, LAVi und TRVmax) auf ihre prognostische Relevanz untersucht. Die abschließende Untersuchung gruppierte die PatientInnen anhand der Schwere ihrer diastolischen Dysfunktion (mild / moderat / schwer) und untersuchte ebenfalls das Langzeitüberleben.
Die HFmrEF-Gruppe zeigte ähnliche klinische Charakteristika wie die HFrEF-Gruppe. Eine ischämische Genese der Herzinsuffizienz wurde in der HFmrEF-Gruppe im Vergleich zur HFrEF-Gruppe häufiger beobachtet.
Die Überlebenszeitanalysen konnten bei PatientInnen in der HFmrEF-Gruppe zeigen, dass ein dilatierter linker Vorhof (LAVi) oder eine große Regurgitation über der Trikuspidalklappe (TRVmax) mit einer schlechten Prognose einhergehen. Bei HFrEF-PatientInnen hingegen konnte dies nicht nachgewiesen werden. Hier zeigte sich, dass insbesondere der Parameter E/e’septal prognostisch relevante Informationen enthält.
Die Auswertung der Untersuchungsgruppen nach Einteilung anhand der Schwere der diastolischen Dysfunktion konnte die gefunden Effekte bestätigen. Eine moderate bis schwere diastolische Dysfunktion war mit einer signifikant schlechteren Prognose behaftet, und zwar sowohl in der HFrEF- wie auch in der HFmrEF-Gruppe.
Die gefunden Ergebnisse zeigen, dass die diastolische Dysfunktion auch bei PatientInnen mit einer systolischen Herzinsuffizienz wichtige prognostische Informationen enthalten. In der klinischen Routine sollte die echokardiographische Bestimmung der diastolischen Herzfunktion standardmäßig durchgeführt werden.
Die Ergebnisse könnten nicht nur in der Diagnostik zur Kategorisierung der PatientInnen und Bestimmung der Prognose, sondern auch hinsichtlich der Therapie von großem zukünftigem Nutzen sein. Hierzu sollten perspektivisch vor allem therapeutische Aspekte in prospektiven, idealerweise randomisierten Studien untersucht werden, welche sich auf die Erkenntnisse dieser Arbeit beziehen.
N2 - This study evaluated the echocardiographic measured diastolic dysfunction in heart failure patients with mid-range or reduced left ventricular ejection fraction.
Conclusions:
We could demonstrate, that moderate to severe diastolic dysfunction identified by echocardiography is significantly associated with all-cause mortality both in patients with HFrEF and HFmrEF. Septal E/E' ratio serves es an independent determinant of all-cause mortality in patients with HFrEF but not in patients with HFmrEF. LAVi and TRVmax could be useful as an independent determinant of all-cause mortality in patients with HFmrEF.
KW - Herzinsuffizienz
KW - Transthorakale Echokardiographie
KW - heart failure
KW - HFrEF
KW - HFmrEF
KW - diagnostic
KW - prognostic
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241704
ER -
TY - THES
A1 - Riedl, Katharina Alina
T1 - Optimierung und Validierung einer MRT-Messmethode zur Quantifizierung der Wandschubspannung in arteriellen Gefäßen zur Evaluation der atherosklerotischen Plaqueentwicklung
T1 - Optimization and validation of an MR imaging method to quantify wall shear stress in arterial vessels to evaluate the atherosclerotic plaque development
N2 - Herz-Kreislauf-Erkrankungen stellen weiterhin die Todesursache Nummer eins in Deutschland dar, welche hauptsächlich durch Atherosklerose verursacht werden. Als ein Prädiktor der atherosklerotischen Plaqueentwicklung wird die Wandschubspannung (WSS) diskutiert. Ziel dieser Arbeit war es daher, anhand von Flussphantomen und C57bl/6 Mäusen eine 2D-Gradientenecho-Bildgebungsmethode mit einer 3D-Phasenkontrast-Flusskodierung zu optimieren und anschließend eine longitudinale Kleintierstudie mit ApoE-/- Mäusen durchzuführen, um den Zusammenhang der WSS und der atherosklerotischen Plaqueentwicklung näher zu untersuchen. Zunächst wurden Flussphantome mit einem Schlauchdurchmesser von 4 mm und 1 mm zur Optimierung der Messmethode verwendet. Anschließend wurde die Messmethode weiter angepasst, um in vivo Messungen an C57bl/6 Mäusen durchführen zu können. Nach erfolgter Optimierung wurde eine longitudinale Kleintierstudie mit zwei verschiedenen Diäten, Western Diät und Chow Diät, durchgeführt. Im Rahmen der Studie erfolgten nach einer, acht und zwölf Wochen MR-Messungen sowie histologische Analysen. Es konnte gezeigt werden, dass die Wandschubspannung in Mäusen bei 17,6 Tesla quantifiziert werden kann. Es zeigte sich eine Tendenz, dass Plaqueformationen mit einer höheren Wandschubspannung einhergehen.
N2 - Cardiovascular diseases are the number one of death in Germany, which are mainly caused by atherosclerosis. Wall shear stress (WSS) is discussed as a predictor for atherosclerotic plaque development. The aim of this study was the optimization and validation of a 2D gradient echo imaging method with a 3D phase contrast flow encoding using flow phantoms and C57bl/6 mice and to perform a longitudinal study with ApoE-/- mice to examine the context of WSS and atherosclerotic plaque development. First, flow phantoms with a tube diameter of 4 mm and 1 mm were used to optimize the imaging method. Therefore, the imaging method was further adapted to examine in vivo C57bl/6 mice. After optimization, a longitudinal animal study was performed with two different diets, Western diet and Chow diet. MR measurements and histological analyses were performed after one, eight, and twelve weeks. It could be shown that WSS can be quantified in mice using 17.6 Tesla MRI. There was a tendency towards higher values of wall shear stress in vessels affected by plaque formations.
KW - Wandschubspannung
KW - Kernspintomografie
KW - Maus
KW - wall shear stress
KW - Ultrahochfeldmagnetresonanztomographie
KW - ultra highfield magnetic resonance imaging
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230814
ER -
TY - THES
A1 - Kuhn, Johannes Helmut Max
T1 - IP\(_3\)-vermittelte Aktivierung des mitochondrialen Metabolismus
T1 - IP\(_3\)-mediated activation of the mitochondrial metabolism
N2 - Mit jedem Herzschlag werden enorme Mengen an Kalzium (Ca2+) in der Herzmuskelzelle freigesetzt. Dies geschieht vornehmlich über Ryanodinrezeptororen (RyR) und dient der Induktion der Muskelkontraktion. Daneben vermittelt aber auch der Inositoltrisphosphat (IP3)-Rezeptor, nach Aktivierung durch den Botenstoff IP3, unabhängig von der Elektromechanischen Kopplung eine Ca2+-Freisetzung aus dem sarkoplasmatischen Retikulum (SR). Die hier vorliegende Arbeit hatte das Ziel an isolierten Herzmuskelzellen die Interaktion von SR und Mitochondrien zu untersuchen, unter besonderer Berücksichtigung einer IP3-vermittelten Aktivierung des mitochondrialen Metabolismus. Wir verglichen den Effekt einer IP3- bzw. RyR-vermittelten zytosolischen Ca2+-Erhöhung auf die mitochondriale Ca2+-Aufnahme und Adenosintriphosphat (ATP)-Produktion. Sowohl unter den IP3-Rezeptor-Agonisten Endothelin-1 (ET-1) bzw. Angiotensin II (Ang II), als auch unter Verwendung des ß-Rezeptor-Agonisten Isoprenalin war eine mitochondriale Ca2+-Aufnahme nachweisbar, allerdings kam es nur IP3-abhängig zu einer ATP-Produktion. Unter Zugabe des IP3-Rezeptor-Blockers 2-Aminoethoxydiphenylborat (2-APB) konnte die zuvor nachgewiesene mitochondriale Ca2+-Aufnahme deutlich reduziert werden, gleiches zeigte sich bei Zellen isoliert aus transgenen IP3-sponge-Mäusen, entsprechend einem funktionellen IP3-Knockout. Hinsichtlich des Mechanismus der mitochondrialen Ca2+-Aufnahme kamen prinzipell zwei Strukturen in Frage: der mitochondriale Ryanodinrezeptor (mRyR1) und der mitochondriale Ca2+-Kanal (MCU). Wir unternahmen in der Folge weitere Versuche mit den anerkannten Rezeptorblockern Ru360 bzw. Dantrolen, um wechselseitig den MCU oder den mRyR1 zu blockieren. Das Ergebnis dieser Versuchsreihe legt den Schluss nahe, dass die Ca2+-Aufnahme in die Mitochondrien nach betaadrenerger Stimulation mit Isoprenalin primär über den MCU vermittelt wird, demgegenüber erfolgt die IP3-vermittelte Ca2+-Aufnahme über den mRyR1. Unter Verwendung von immunhistochemischer Färbungen identifizierten wir den IP3-Rezeptor vom Typ III, der ein überwiegend mitochondriales Verteilungsmuster aufzeigte. Wir schließen daraus, dass die von uns beobachteten Effekte der mitochondrialen Ca2+-Aufnahme und ATP-Produktion IP3-abhängig induziert werden bzw. zu einem Großteil auf eine Aktivität des IP3-Rezeptors, vermutlich der Unterform vom Typ III, zurückzuführen sind. Zusammenfassend konnte in der hier vorgelegten Arbeit gezeigt werden, dass die Aktivität des IP3-Rezeptors wesentlich am zellulären Energiehaushalt der Kardiomyozyten beteiligt ist. Der IP3-Signalweg vermittelt die Ca2+-Aufnahme in die Mitochondrien und führt so zu einer Energiebereitstellung in Form von ATP.
N2 - In this study we aimed to investigate the interaction of sarcoplasmatic reticulum (SR) and mitochondria in isolated cardiac myocytes, with special consideration of an IP3-mediated activation of the mitochondrial metabolism. We compared the effects of IP3-Receptor and Ryanodin-Receptor (RyR)-mediated cytosolic Ca2+-elevation on mitochondrial Ca2+-uptake and adenosine triphosphate (ATP) generation achieved by the IP3-receptor agonists endothelin-1 (ET-1) and angiotensin II (Ang II) and the β-adrenergic agonist isoproterenol (ISO). The IP3-receptor-agonists ET-1 and Ang II as well as ISO induced an increase in mitochondrial Ca2+, but only IP3-dependent we observed an increase in ATP concentration. ET-1 induced effects were prevented by cell treatment with the IP3-antagonist 2-aminoethyoxydiphenyl borate (2-APB) and absent in myocytes from transgenic mice expressing an IP3 chelating protein (IP3 sponge). Furthermore IP3-induced mitochondrial Ca2+-uptake was insensitive to the mitochondrial Ca2+-uniporter inhibitor Ru360, however was attenuated by RyR type 1 inhibitor dantrolene. Using immunostaining with specific IP3R antibodies, we demonstrated different expression patterns of each IP3R subtype. The immunofluorescence pattern of the IP3R type 3 shows a mitochondrial distribution, so that the type 3 IP3R is most likely the subtype involved in the observed effects. Altogether, our data indicate that the activity of IP3-Receptors is important for modulation of cellular energetics and ATP-generation in cardiac myocytes.
KW - Inositoltrisphosphat
KW - Mitochondrien
KW - Calcium
KW - IP3-sponge
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236259
ER -
TY - JOUR
A1 - Weich, Alexander
A1 - Werner, Rudolf A.
A1 - Buck, Andreas K.
A1 - Hartrampf, Philipp E.
A1 - Serfling, Sebastian E.
A1 - Scheurlen, Michael
A1 - Wester, Hans-Jürgen
A1 - Meining, Alexander
A1 - Kircher, Stefan
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Lapa, Constantin
A1 - Kircher, Malte
T1 - CXCR4-Directed PET/CT in Patients with Newly Diagnosed Neuroendocrine Carcinomas
JF - Diagnostics
N2 - We aimed to elucidate the diagnostic potential of the C-X-C motif chemokine receptor 4 (CXCR4)-directed positron emission tomography (PET) tracer \(^{68}\)Ga-Pentixafor in patients with poorly differentiated neuroendocrine carcinomas (NEC), relative to the established reference standard \(^{18}\)F-FDG PET/computed tomography (CT). In our database, we retrospectively identified 11 treatment-naïve patients with histologically proven NEC, who underwent \(^{18}\)F-FDG and CXCR4-directed PET/CT for staging and therapy planning. The images were analyzed on a per-patient and per-lesion basis and compared to immunohistochemical staining (IHC) of CXCR4 from PET-guided biopsies. \(^{68}\)Ga-Pentixafor visualized tumor lesions in 10/11 subjects, while \(^{18}\)F-FDG revealed sites of disease in all 11 patients. Although weak to moderate CXCR4 expression could be corroborated by IHC in 10/11 cases, \(^{18}\)F-FDG PET/CT detected significantly more tumor lesions (102 vs. 42; total lesions, n = 107; p < 0.001). Semi-quantitative analysis revealed markedly higher 18F-FDG uptake as compared to \(^{68}\)Ga-Pentixafor (maximum and mean standardized uptake values (SUV) and tumor-to-background ratios (TBR) of cancerous lesions, SUVmax: 12.8 ± 9.8 vs. 5.2 ± 3.7; SUVmean: 7.4 ± 5.4 vs. 3.1 ± 3.2, p < 0.001; and, TBR 7.2 ± 7.9 vs. 3.4 ± 3.0, p < 0.001). Non-invasive imaging of CXCR4 expression in NEC is inferior to the reference standard \(^{18}\)F-FDG PET/CT.
KW - CXCR4
KW - NET
KW - NEC
KW - 68Ga-Pentixafor
KW - 18F-FDG
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234231
SN - 2075-4418
VL - 11
IS - 4
ER -
TY - THES
A1 - Albert, Judith
T1 - Longitudinale Veränderungen der kardialen Funktion und Struktur nach akuter kardialer Dekompensation aufgrund systolischer Herzinsuffizienz: Prognostische Bedeutung, Prädiktoren und assoziierte laborchemische und echokardiographische Veränderungen einer Normalisierung der linksventrikulären systolischen Funktion
T1 - Trajectories of left ventricular ejection fraction after acute decompensation for systolic heart failure: concomitant echocardiographic and systemic changes, predictors, and impact on clinical outcomes
N2 - Der Krankheitsverlauf der Herzinsuffizienz ist variabel. Typischerweise treten dabei wiederholte Episoden akuter kardialer Dekompensationen auf. Prospektive Untersuchungen zu longitudinalen Veränderungen der linksventrikulären Ejektionsfraktion (LVEF) nach akuter kardialer Dekompensation, sowie assoziierter echokardiographischer, laborchemischer und klinischer Parameter fehlten bisher.
Ziel der vorliegenden Arbeit war es deshalb, die Häufigkeit einer Verbesserung bzw.
Normalisierung der LVEF innerhalb von sechs Monaten nach einer Hospitalisierung aufgrund
akuter kardialer Dekompensation mit systolischer Herzinsuffizienz (LVEF vor Entlassung aus
dem Krankenhaus ≤40%), sowie begleitende Veränderungen in Biomarkerspiegeln und
echokardiographischen Parametern, zu beschreiben, deren prognostische Relevanz zu
untersuchen und mögliche Prädiktoren zu ermitteln.
Die Ergebnisse der Arbeit zeigen, dass in den folgenden 6 Monaten nach akuter kardialer Dekompensation variable LVEF-Verläufe zu erwarten sind. Mehr als 50% der Patienten erleben ein reverses Remodelling und wechseln dadurch die LVEF-basierte Herzinsuffizienz-Kategorie. LVEF-Verbesserungen sind mit komplexen kardialen, extrakardialen und klinischen Veränderungen - im Sinne eines systemischen reversen Remodellings – assoziiert und gehen mit einer verbesserten Langzeitprognose einher. Verschiedene Prädiktoren erlauben, nach akuter kardialer Dekompensation den Verlauf bereits bei Krankenhausentlassung abzuschätzen und damit personalisierte Behandlungsstrategien für den einzelnen Patienten zu etablieren.
N2 - Typically, the heart failure (HF) trajectory is characterized by repeat episodes of acute cardiac decompensation (ACD), which often necessitate hospitalization. However, prospective longitudinal follow-up information on left ventricular ejection fraction (LVEF) trajectories after ACD is lacking to-date. We therefore investigated in patients with a pre-discharge LVEF ≤40% changes in LVEF and other echocardiographic, clinical and laboratory parameters at 6-months’ follow-up, determined predictors, and studied prognostic implications of LVEF changes through 18-months follow-up.
LVEF recovery after ACD was common in our study population with improvements by ≥1 HF category in >50%. LVEF changes correlated with several other clinical, laboratory and echocardiographic parameters, suggesting multilevel reverse remodelling. LVEF recovery was associated with better clinical outcomes and predictable from different independent baseline variables, thus facilitating early risk stratification and tailored, risk-adapted care after ACD.
KW - Herzinsuffizienz
KW - Kardiale Dekompensation
KW - Linksventrikuläre systolische Funktion
KW - Recovery
KW - Prädiktoren
KW - Prognostische Bedeutung
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230592
ER -
TY - JOUR
A1 - Ankenbrand, Markus Johannes
A1 - Lohr, David
A1 - Schlötelburg, Wiebke
A1 - Reiter, Theresa
A1 - Wech, Tobias
A1 - Schreiber, Laura Maria
T1 - Deep learning-based cardiac cine segmentation: Transfer learning application to 7T ultrahigh-field MRI
JF - Magnetic Resonance in Medicine
N2 - Purpose
Artificial neural networks show promising performance in automatic segmentation of cardiac MRI. However, training requires large amounts of annotated data and generalization to different vendors, field strengths, sequence parameters, and pathologies is limited. Transfer learning addresses this challenge, but specific recommendations regarding type and amount of data required is lacking. In this study, we assess data requirements for transfer learning to experimental cardiac MRI at 7T where the segmentation task can be challenging. In addition, we provide guidelines, tools, and annotated data to enable transfer learning approaches by other researchers and clinicians.
Methods
A publicly available segmentation model was used to annotate a publicly available data set. This labeled data set was subsequently used to train a neural network for segmentation of left ventricle and myocardium in cardiac cine MRI. The network is used as starting point for transfer learning to 7T cine data of healthy volunteers (n = 22; 7873 images) by updating the pre-trained weights. Structured and random data subsets of different sizes were used to systematically assess data requirements for successful transfer learning.
Results
Inconsistencies in the publically available data set were corrected, labels created, and a neural network trained. On 7T cardiac cine images the model pre-trained on public imaging data, acquired at 1.5T and 3T, achieved DICE\(_{LV}\) = 0.835 and DICE\(_{MY}\) = 0.670. Transfer learning using 7T cine data and ImageNet weight initialization improved model performance to DICE\(_{LV}\) = 0.900 and DICE\(_{MY}\) = 0.791. Using only end-systolic and end-diastolic images reduced training data by 90%, with no negative impact on segmentation performance (DICE\(_{LV}\) = 0.908, DICE\(_{MY}\) = 0.805).
Conclusions
This work demonstrates and quantifies the benefits of transfer learning for cardiac cine image segmentation. We provide practical guidelines for researchers planning transfer learning projects in cardiac MRI and make data, models, and code publicly available.
KW - 7T
KW - ultrahigh-field
KW - transfer learning
KW - segmentation
KW - neural networks
KW - deep learning
KW - cardiac magnetic resonance
KW - cardiac function
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257604
VL - 86
IS - 4
ER -
TY - JOUR
A1 - Fuss, Carmina Teresa
A1 - Other, Katharina
A1 - Heinze, Britta
A1 - Landwehr, Laura-Sophie
A1 - Wiegering, Armin
A1 - Kalogirou, Charis
A1 - Hahner, Stefanie
A1 - Fassnacht, Martin
T1 - Expression of the chemokine receptor CCR7 in the normal adrenal gland and adrenal tumors and its correlation with clinical outcome in adrenocortical carcinoma
JF - Cancers
N2 - Background: The chemokine receptor CCR7 is crucial for an intact immune function, but its expression is also associated with clinical outcome in several malignancies. No data exist on the expression of CCR7 in adrenocortical tumors. Methods: CCR7 expression was investigated by qRT-PCR and immunohistochemistry in 4 normal adrenal glands, 59 adrenocortical adenomas, and 181 adrenocortical carcinoma (ACC) samples. Results: CCR7 is highly expressed in the outer adrenocortical zones and medulla. Aldosterone-producing adenomas showed lower CCR7 protein levels (H-score 1.3 ± 1.0) compared to non-functioning (2.4 ± 0.5) and cortisol-producing adenomas (2.3 ± 0.6), whereas protein expression was variable in ACC (1.8 ± 0.8). In ACC, CCR7 protein expression was significantly higher in lymph node metastases (2.5 ± 0.5) compared to primary tumors (1.8±0.8) or distant metastases (2.0 ± 0.4; p < 0.01). mRNA levels of CCR7 were not significantly different between ACCs, normal adrenals, and adrenocortical adenomas. In contrast to other tumor entities, neither CCR7 protein nor mRNA expression significantly impacted patients' survival. Conclusion: We show that CCR7 is expressed on mRNA and protein level across normal adrenals, benign adrenocortical tumors, as well as ACCs. Given that CCR7 did not influence survival in ACC, it is probably not involved in tumor progression, but it could play a role in adrenocortical homeostasis.
KW - CCR7
KW - chemokine receptor
KW - adrenocortical carcinoma
KW - adrenal tumors
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250112
SN - 2072-6694
VL - 13
IS - 22
ER -
TY - JOUR
A1 - Sbiera, Iuliu
A1 - Kircher, Stefan
A1 - Altieri, Barbara
A1 - Fassnacht, Martin
A1 - Kroiss, Matthias
A1 - Sbiera, Silviu
T1 - Epithelial and Mesenchymal Markers in Adrenocortical Tissues: How Mesenchymal Are Adrenocortical Tissues?
JF - Cancers
N2 - A clinically relevant proportion of adrenocortical carcinoma (ACC) cases shows a tendency to metastatic spread. The objective was to determine whether the epithelial to mesenchymal transition (EMT), a mechanism associated with metastasizing in several epithelial cancers, might play a crucial role in ACC. 138 ACC, 29 adrenocortical adenomas (ACA), three normal adrenal glands (NAG), and control tissue samples were assessed for the expression of epithelial (E-cadherin and EpCAM) and mesenchymal (N-cadherin, SLUG and SNAIL) markers by immunohistochemistry. Using real-time RT-PCR we quantified the alternative isoform splicing of FGFR 2 and 3, another known indicator of EMT. We also assessed the impact of these markers on clinical outcome. Results show that both normal and neoplastic adrenocortical tissues lacked expression of epithelial markers but strongly expressed mesenchymal markers N-cadherin and SLUG. FGFR isoform splicing confirmed higher similarity of adrenocortical tissues to mesenchymal compared to epithelial tissues. In ACC, higher SLUG expression was associated with clinical markers indicating aggressiveness, while N-cadherin expression inversely associated with these markers. In conclusion, we could not find any indication of EMT as all adrenocortical tissues lacked expression of epithelial markers and exhibited closer similarity to mesenchymal tissues. However, while N-cadherin might play a positive role in tissue structure upkeep, SLUG seems to be associated with a more aggressive phenotype.
KW - adrenocortical tissues
KW - EMT
KW - epithelial markers
KW - mesenchymal markers
KW - recurrence-free survival
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236486
SN - 2072-6694
VL - 13
IS - 7
ER -
TY - JOUR
A1 - Monteagudo, María
A1 - Martínez, Paula
A1 - Leandro-García, Luis J.
A1 - Martínez-Montes, Ángel M.
A1 - Calsina, Bruna
A1 - Pulgarín-Alfaro, Marta
A1 - Díaz-Talavera, Alberto
A1 - Mellid, Sara
A1 - Letón, Rocío
A1 - Gil, Eduardo
A1 - Pérez-Martínez, Manuel
A1 - Megías, Diego
A1 - Torres-Ruiz, Raúl
A1 - Rodriguez-Perales, Sandra
A1 - González, Patricia
A1 - Caleiras, Eduardo
A1 - Jiménez-Villa, Scherezade
A1 - Roncador, Giovanna
A1 - Álvarez-Escolá, Cristina
A1 - Regojo, Rita M.
A1 - Calatayud, María
A1 - Guadalix, Sonsoles
A1 - Currás-Freixes, Maria
A1 - Rapizzi, Elena
A1 - Canu, Letizia
A1 - Nölting, Svenja
A1 - Remde, Hanna
A1 - Fassnacht, Martin
A1 - Bechmann, Nicole
A1 - Eisenhofer, Graeme
A1 - Mannelli, Massimo
A1 - Beuschlein, Felix
A1 - Quinkler, Marcus
A1 - Rodríguez-Antona, Cristina
A1 - Cascón, Alberto
A1 - Blasco, María A.
A1 - Montero-Conde, Cristina
A1 - Robledo, Mercedes
T1 - Analysis of telomere maintenance related genes reveals NOP10 as a new metastatic-risk marker in pheochromocytoma/paraganglioma
JF - Cancers
N2 - One of the main problems we face with PPGL is the lack of molecular markers capable of predicting the development of metastases in patients. Telomere-related genes, such as TERT and ATRX, have been recently described in PPGL, supporting the association between the activation of immortalization mechanisms and disease progression. However, the contribution of other genes involving telomere preservation machinery has not been previously investigated. In this work, we aimed to analyze the prognostic value of a comprehensive set of genes involved in telomere maintenance. For this study, we collected 165 PPGL samples (97 non-metastatic/63 metastatic), genetically characterized, in which the expression of 29 genes of interest was studied by NGS. Three of the 29 genes studied, TERT, ATRX and NOP10, showed differential expression between metastatic and non-metastatic cases, and alterations in these genes were associated with a shorter time to progression, independent of SDHB-status. We studied telomere length by Q-FISH in patient samples and in an in vitro model. NOP10 overexpressing tumors displayed an intermediate-length telomere phenotype without ALT, and in vitro results suggest that NOP10 has a role in telomerase-dependent telomere maintenance. We also propose the implementation of NOP10 IHC to better stratify PPGL patients.
KW - pheochromocytoma
KW - paraganglioma
KW - PPGL
KW - telomeres
KW - prognostic biomarker
KW - ALT
KW - TERT
KW - ATRX
KW - NOP10
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246321
SN - 2072-6694
VL - 13
IS - 19
ER -
TY - JOUR
A1 - Lenschow, Christina
A1 - Fuss, Carmina Teresa
A1 - Kircher, Stefan
A1 - Buck, Andreas
A1 - Kickuth, Ralph
A1 - Reibetanz, Joachim
A1 - Wiegering, Armin
A1 - Stenzinger, Albrecht
A1 - Hübschmann, Daniel
A1 - Germer, Christoph Thomas
A1 - Fassnacht, Martin
A1 - Fröhling, Stefan
A1 - Schlegel, Nicolas
A1 - Kroiss, Matthias
T1 - Case Report: Abdominal Lymph Node Metastases of Parathyroid Carcinoma: Diagnostic Workup, Molecular Diagnosis, and Clinical Management
JF - Frontiers in Endocrinology
N2 - Parathyroid carcinoma (PC) is an orphan malignancy accounting for only ~1% of all cases with primary hyperparathyroidism. The localization of recurrent PC is of critical importance and can be exceedingly difficult to diagnose and sometimes futile when common sites of recurrence in the neck and chest cannot be confirmed. Here, we present the diagnostic workup, molecular analysis and multimodal therapy of a 46-year old woman with the extraordinary manifestation of abdominal lymph node metastases 12 years after primary diagnosis of PC. The patient was referred to our endocrine tumor center in 2016 with the aim to localize the tumor causative of symptomatic biochemical recurrence. In view of the extensive previous workup we decided to perform [18F]FDG-PET-CT. A pathological lymph node in the liver hilus showed slightly increased FDG-uptake and hence was suspected as site of recurrence. Selective venous sampling confirmed increased parathyroid hormone concentration in liver veins. Abdominal lymph node metastasis was resected and histopathological examination confirmed PC. Within four months, the patient experienced biochemical recurrence and based on high tumor mutational burden detected in the surgical specimen by whole exome sequencing the patient received immunotherapy with pembrolizumab that led to a biochemical response. Subsequent to disease progression repeated abdominal lymph node resection was performed in 10/2018, 01/2019 and in 01/2020. Up to now (12/2020) the patient is biochemically free of disease. In conclusion, a multimodal diagnostic approach and therapy in an interdisciplinary setting is needed for patients with rare endocrine tumors. Molecular analyses may inform additional treatment options including checkpoint inhibitors such as pembrolizumab.
KW - parathyroid carcinoma
KW - abdominal lymph node metastases
KW - molecular diagnostics
KW - repeated surgery
KW - [18F]FDG-PET-CT
KW - immune check inhibitor
KW - pembrolizumab
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-233362
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Hauser, T.
A1 - Dornberger, V.
A1 - Malzahn, U.
A1 - Grebe, S. J.
A1 - Liu, D.
A1 - Störk, S.
A1 - Nauck, M.
A1 - Friedrich, N.
A1 - Dörr, M.
A1 - Wanner, C.
A1 - Krane, V.
A1 - Hammer, F.
T1 - The effect of spironolactone on diastolic function in haemodialysis patients
JF - The International Journal of Cardiovascular Imaging
N2 - Heart failure with preserved ejection fraction (HFpEF) is highly prevalent in patients on maintenance haemodialysis (HD) and lacks effective treatment. We investigated the effect of spironolactone on cardiac structure and function with a specific focus on diastolic function parameters. The MiREnDa trial examined the effect of 50 mg spironolactone once daily versus placebo on left ventricular mass index (LVMi) among 97 HD patients during 40 weeks of treatment. In this echocardiographic substudy, diastolic function was assessed using predefined structural and functional parameters including E/e'. Changes in the frequency of HFpEF were analysed using the comprehensive 'HFA-PEFF score'. Complete echocardiographic assessment was available in 65 individuals (59.5 ± 13.0 years, 21.5% female) with preserved left ventricular ejection fraction (LVEF > 50%). At baseline, mean E/e' was 15.2 ± 7.8 and 37 (56.9%) patients fulfilled the criteria of HFpEF according to the HFA-PEFF score. There was no significant difference in mean change of E/e' between the spironolactone group and the placebo group (+ 0.93 ± 5.39 vs. + 1.52 ± 5.94, p = 0.68) or in mean change of left atrial volume index (LAVi) (1.9 ± 12.3 ml/m\(^{2}\) vs. 1.7 ± 14.1 ml/m\(^{2}\), p = 0.89). Furthermore, spironolactone had no significant effect on mean change in LVMi (+ 0.8 ± 14.2 g/m\(^{2}\) vs. + 2.7 ± 15.9 g/m\(^{2}\); p = 0.72) or NT-proBNP (p = 0.96). Treatment with spironolactone did not alter HFA-PEFF score class compared with placebo (p = 0.63). Treatment with 50 mg of spironolactone for 40 weeks had no significant effect on diastolic function parameters in HD patients.
KW - HFpEF
KW - diastolic function
KW - echocardiography
KW - E/e’
KW - haemodialysis
KW - spironolactone
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-269033
SN - 1573-0743
VL - 37
IS - 6
ER -
TY - JOUR
A1 - Basile, Vittoria
A1 - Puglisi, Soraya
A1 - Altieri, Barbara
A1 - Canu, Letizia
A1 - Libè, Rossella
A1 - Ceccato, Filippo
A1 - Beuschlein, Felix
A1 - Quinkler, Marcus
A1 - Calabrese, Anna
A1 - Perotti, Paola
A1 - Berchialla, Paola
A1 - Dischinger, Ulrich
A1 - Megerle, Felix
A1 - Baudin, Eric
A1 - Bourdeau, Isabelle
A1 - Lacroix, André
A1 - Loli, Paola
A1 - Berruti, Alfredo
A1 - Kastelan, Darko
A1 - Haak, Harm R.
A1 - Fassnacht, Martin
A1 - Terzolo, Massimo
T1 - What is the optimal duration of adjuvant mitotane therapy in adrenocortical carcinoma? An unanswered question
JF - Journal of Personalized Medicine
N2 - A relevant issue on the treatment of adrenocortical carcinoma (ACC) concerns the optimal duration of adjuvant mitotane treatment. We tried to address this question, assessing whether a correlation exists between the duration of adjuvant mitotane treatment and recurrence-free survival (RFS) of patients with ACC. We conducted a multicenter retrospective analysis on 154 ACC patients treated for ≥12 months with adjuvant mitotane after radical surgery and who were free of disease at the mitotane stop. During a median follow-up of 38 months, 19 patients (12.3%) experienced recurrence. We calculated the RFS after mitotane (RFSAM), from the landmark time-point of mitotane discontinuation, to overcome immortal time bias. We found a wide variability in the duration of adjuvant mitotane treatment among different centers and also among patients cared for at the same center, reflecting heterogeneous practice. We did not find any survival advantage in patients treated for longer than 24 months. Moreover, the relationship between treatment duration and the frequency of ACC recurrence was not linear after stratifying our patients in tertiles of length of adjuvant treatment. In conclusion, the present findings do not support the concept that extending adjuvant mitotane treatment over two years is beneficial for ACC patients with low to moderate risk of recurrence.
KW - mitotane
KW - adjuvant treatment
KW - adrenocortical cancer
KW - recurrence
KW - recurrence free survival
KW - timing
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236507
SN - 2075-4426
VL - 11
IS - 4
ER -
TY - THES
A1 - Leucht, Annalena
T1 - Einfluss der mitochondrialen Ca\(^{2+}\)-Aufnahme auf die nukleäre Ca\(^{2+}\)-Konzentration in ventrikulären Kardiomyozyten der Maus
T1 - The effect of mitochondrial Ca\(^{2+}\) uptake on the nuclear Ca\(^{2+}\) concentration in murine ventricular cardiomyocytes
N2 - Nach Stimulierung mit einem IP3-Rezeptor Agonisten wird die mitochondriale Ca2+-Aufnahme stimuliert. Wenn diese mitochondriale Ca2+-Aufnahme durch Dantrolen oder Ru360 blockiert wird, dann steigt nachfolgend das zytosolische [Ca2+] an. Nach Blockierung des mRyR durch Dantrolen steigt zusätzlich durch die Beeinflussung der passiven Komponente des nukleären Ca2+-Transienten das nukleäre [Ca2+] an. Dieses erhöhte nukleäre [Ca2+] hat letztlich eine Hypertrophie zur Folge. Somit können Mitochondrien, die in ihrer Funktion gestört sind, zur Entwicklung der Hypertrophie beitragen.
N2 - After treatment with an IP3-receptor agonist mitochondria takes up calcium. If this uptake is blocked by dantrolene or Ru 360 the cytosolic calcium increases. When the mRyR is blocked by dantrolene the nuclear calcium is additionally increased.
KW - Mitochondrium
KW - Herzinsuffizienz
KW - Calcium-Aufnahme
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-220289
ER -
TY - JOUR
A1 - Bothou, Christina
A1 - Sharma, Ashish
A1 - Oo, Adrian
A1 - Kim, Baek
A1 - Perge, Pal
A1 - Igaz, Peter
A1 - Ronchi, Cristina L.
A1 - Shapiro, Igor
A1 - Hantel, Constanze
T1 - Novel insights into the molecular regulation of ribonucleotide reductase in adrenocortical carcinoma treatment
JF - Cancers
N2 - Current systemic treatment options for patients with adrenocortical carcinomas (ACCs) are far from being satisfactory. DNA damage/repair mechanisms, which involve, e.g., ataxia-telangiectasia-mutated (ATM) and ataxia-telangiectasia/Rad3-related (ATR) protein signaling or ribonucleotide reductase subunits M1/M2 (RRM1/RRM2)-encoded ribonucleotide reductase (RNR) activation, commonly contribute to drug resistance. Moreover, the regulation of RRM2b, the p53-induced alternative to RRM2, is of unclear importance for ACC. Upon extensive drug screening, including a large panel of chemotherapies and molecular targeted inhibitors, we provide strong evidence for the anti-tumoral efficacy of combined gemcitabine (G) and cisplatin (C) treatment against the adrenocortical cell lines NCI-H295R and MUC-1. However, accompanying induction of RRM1, RRM2, and RRM2b expression also indicated developing G resistance, a frequent side effect in clinical patient care. Interestingly, this effect was partially reversed upon addition of C. We confirmed our findings for RRM2 protein, RNR-dependent dATP levels, and modulations of related ATM/ATR signaling. Finally, we screened for complementing inhibitors of the DNA damage/repair system targeting RNR, Wee1, CHK1/2, ATR, and ATM. Notably, the combination of G, C, and the dual RRM1/RRM2 inhibitor COH29 resulted in previously unreached total cell killing. In summary, we provide evidence that RNR-modulating therapies might represent a new therapeutic option for ACC.
KW - adrenocortical carcinoma
KW - adrenocortical cell line
KW - RRM2
KW - RNR
KW - COH29
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-245132
SN - 2072-6694
VL - 13
IS - 16
ER -
TY - JOUR
A1 - Dischinger, Ulrich
A1 - Heckel, Tobias
A1 - Bischler, Thorsten
A1 - Hasinger, Julia
A1 - Königsrainer, Malina
A1 - Schmitt-Böhrer, Angelika
A1 - Otto, Christoph
A1 - Fassnacht, Martin
A1 - Seyfried, Florian
A1 - Hankir, Mohammed Khair
T1 - Roux-en-Y gastric bypass and caloric restriction but not gut hormone-based treatments profoundly impact the hypothalamic transcriptome in obese rats
JF - Nutrients
N2 - Background: The hypothalamus is an important brain region for the regulation of energy balance. Roux-en-Y gastric bypass (RYGB) surgery and gut hormone-based treatments are known to reduce body weight, but their effects on hypothalamic gene expression and signaling pathways are poorly studied. Methods: Diet-induced obese male Wistar rats were randomized into the following groups: RYGB, sham operation, sham + body weight-matched (BWM) to the RYGB group, osmotic minipump delivering PYY3-36 (0.1 mg/kg/day), liraglutide s.c. (0.4 mg/kg/day), PYY3-36 + liraglutide, and saline. All groups (except BWM) were kept on a free choice of high- and low-fat diets. Four weeks after interventions, hypothalami were collected for RNA sequencing. Results: While rats in the RYGB, BWM, and PYY3-36 + liraglutide groups had comparable reductions in body weight, only RYGB and BWM treatment had a major impact on hypothalamic gene expression. In these groups, hypothalamic leptin receptor expression as well as the JAK–STAT, PI3K-Akt, and AMPK signaling pathways were upregulated. No significant changes could be detected in PYY3-36 + liraglutide-, liraglutide-, and PYY-treated groups. Conclusions: Despite causing similar body weight changes compared to RYGB and BWM, PYY3-36 + liraglutide treatment does not impact hypothalamic gene expression. Whether this striking difference is favorable or unfavorable to metabolic health in the long term requires further investigation.
KW - obesity
KW - Roux-en-Y gastric bypass surgery
KW - liraglutide
KW - PYY3-36
KW - hypothalamic gene expression
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-252392
SN - 2072-6643
VL - 14
IS - 1
ER -
TY - JOUR
A1 - Kaspar, Mathias
A1 - Fette, Georg
A1 - Hanke, Monika
A1 - Ertl, Maximilian
A1 - Puppe, Frank
A1 - Störk, Stefan
T1 - Automated provision of clinical routine data for a complex clinical follow-up study: A data warehouse solution
JF - Health Informatics Journal
N2 - A deep integration of routine care and research remains challenging in many respects. We aimed to show the feasibility of an automated transformation and transfer process feeding deeply structured data with a high level of granularity collected for a clinical prospective cohort study from our hospital information system to the study's electronic data capture system, while accounting for study-specific data and visits. We developed a system integrating all necessary software and organizational processes then used in the study. The process and key system components are described together with descriptive statistics to show its feasibility in general and to identify individual challenges in particular. Data of 2051 patients enrolled between 2014 and 2020 was transferred. We were able to automate the transfer of approximately 11 million individual data values, representing 95% of all entered study data. These were recorded in n = 314 variables (28% of all variables), with some variables being used multiple times for follow-up visits. Our validation approach allowed for constant good data quality over the course of the study. In conclusion, the automated transfer of multi-dimensional routine medical data from HIS to study databases using specific study data and visit structures is complex, yet viable.
KW - clinical data warehouse
KW - clinical study
KW - electronic data capture
KW - electronic health records
KW - secondary data usage
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260828
VL - 28
IS - 1
ER -
TY - JOUR
A1 - Riedmeier, Maria
A1 - Decarolis, Boris
A1 - Haubitz, Imme
A1 - Müller, Sophie
A1 - Uttinger, Konstantin
A1 - Börner, Kevin
A1 - Reibetanz, Joachim
A1 - Wiegering, Armin
A1 - Härtel, Christoph
A1 - Schlegel, Paul-Gerhardt
A1 - Fassnacht, Martin
A1 - Wiegering, Verena
T1 - Adrenocortical carcinoma in childhood: a systematic review
JF - Cancers
N2 - Adrenocortical tumors are rare in children. This systematic review summarizes the published evidence on pediatric adrenocortical carcinoma (ACC) to provide a basis for a better understanding of the disease, investigate new molecular biomarkers and therapeutic targets, and define which patients may benefit from a more aggressive therapeutic approach. We included 137 studies with 3680 ACC patients (~65% female) in our analysis. We found no randomized controlled trials, so this review mainly reflects retrospective data. Due to a specific mutation in the TP53 gene in ~80% of Brazilian patients, that cohort was analyzed separately from series from other countries. Hormone analysis was described in 2569 of the 2874 patients (89%). Most patients were diagnosed with localized disease, whereas 23% had metastasis at primary diagnosis. Only 72% of the patients achieved complete resection. In 334 children (23%), recurrent disease was reported: 81% — local recurrence, 19% (n = 65) — distant metastases at relapse. Patients < 4 years old had a different distribution of tumor stages and hormone activity and better overall survival (p < 0.001). Although therapeutic approaches are typically multimodal, no consensus is available on effective standard treatments for advanced ACC. Thus, knowledge regarding pediatric ACC is still scarce and international prospective studies are needed to implement standardized clinical stratifications and risk-adapted therapeutic strategies.
KW - pediatric adrenocortical cancer
KW - pediatric adrenocortical adenoma
KW - pediatric adrenocortical tumor
KW - prognostic factors
KW - therapy
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248507
SN - 2072-6694
VL - 13
IS - 21
ER -
TY - JOUR
A1 - Popp, Sandy
A1 - Schmitt-Böhrer, Angelika
A1 - Langer, Simon
A1 - Hofmann, Ulrich
A1 - Hommers, Leif
A1 - Schuh, Kai
A1 - Frantz, Stefan
A1 - Lesch, Klaus-Peter
A1 - Frey, Anna
T1 - 5-HTT Deficiency in Male Mice Affects Healing and Behavior after Myocardial Infarction
JF - Journal of Clinical Medicine
N2 - Anxiety disorders and depression are common comorbidities in cardiac patients. Mice lacking the serotonin transporter (5-HTT) exhibit increased anxiety-like behavior. However, the role of 5-HTT deficiency on cardiac aging, and on healing and remodeling processes after myocardial infarction (MI), remains unclear. Cardiological evaluation of experimentally naïve male mice revealed a mild cardiac dysfunction in ≥4-month-old 5-HTT knockout (−/−) animals. Following induction of chronic cardiac dysfunction (CCD) by MI vs. sham operation 5-HTT−/− mice with infarct sizes >30% experienced 100% mortality, while 50% of 5-HTT+/− and 37% of 5-HTT+/+ animals with large MI survived the 8-week observation period. Surviving (sham and MI < 30%) 5-HTT−/− mutants displayed reduced exploratory activity and increased anxiety-like behavior in different approach-avoidance tasks. However, CCD failed to provoke a depressive-like behavioral response in either 5-Htt genotype. Mechanistic analyses were performed on mice 3 days post-MI. Electrocardiography, histology and FACS of inflammatory cells revealed no abnormalities. However, gene expression of inflammation-related cytokines (TGF-β, TNF-α, IL-6) and MMP-2, a protein involved in the breakdown of extracellular matrix, was significantly increased in 5-HTT−/− mice after MI. This study shows that 5-HTT deficiency leads to age-dependent cardiac dysfunction and disrupted early healing after MI probably due to alterations of inflammatory processes in mice.
KW - chronic heart failure
KW - myocardial infarction
KW - serotonin transporter deficient mice
KW - anxiety
KW - depression
KW - behavior
KW - inflammation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242739
SN - 2077-0383
VL - 10
IS - 14
ER -
TY - JOUR
A1 - Aghai, Fatemeh
A1 - Zimmermann, Sebastian
A1 - Kurlbaum, Max
A1 - Jung, Pius
A1 - Pelzer, Theo
A1 - Klinker, Hartwig
A1 - Isberner, Nora
A1 - Scherf-Clavel, Oliver
T1 - Development and validation of a sensitive liquid chromatography tandem mass spectrometry assay for the simultaneous determination of ten kinase inhibitors in human serum and plasma
JF - Analytical and Bioanalytical Chemistry
N2 - A liquid chromatography tandem mass spectrometry method for the analysis of ten kinase inhibitors (afatinib, axitinib, bosutinib,cabozantinib, dabrafenib, lenvatinib, nilotinib, osimertinib, ruxolitinib, and trametinib) in human serum and plasma for theapplication in daily clinical routine has been developed and validated according to the US Food and Drug Administration andEuropean Medicines Agency validation guidelines for bioanalytical methods. After protein precipitation of plasma samples withacetonitrile, chromatographic separation was performed at ambient temperature using a Waters XBridge® Phenyl 3.5μm(2.1×50 mm) column. The mobile phases consisted of water-methanol (9:1, v/v) with 10 mM ammonium bicarbonate as phase A andmethanol-water (9:1, v/v) with 10 mM ammonium bicarbonate as phase B. Gradient elution was applied at a flow rate of 400μL/min. Analytes were detected and quantified using multiple reaction monitoring in electrospray ionization positive mode. Stableisotopically labeled compounds of each kinase inhibitor were used as internal standards. The acquisition time was 7.0 min perrun. All analytes and internal standards eluted within 3.0 min. The calibration curves were linear over the range of 2–500 ng/mLfor afatinib, axitinib, bosutinib, lenvatinib, ruxolitinib, and trametinib, and 6–1500 ng/mL for cabozantinib, dabrafenib, nilotinib,and osimertinib (coefficients of correlation≥0.99). Validation assays for accuracy and precision, matrix effect, recovery,carryover, and stability were appropriate according to regulatory agencies. The rapid and sensitive assay ensures high throughputand was successfully applied to monitor concentrations of kinase inhibitors in patients.
KW - kinase inhibitors
KW - therapeutic drug monitoring
KW - liquid chromatography tandem mass spectrometry (LC-MS/MS
KW - afatinib
KW - osimertinib
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-231925
SN - 1618-2642
VL - 413
ER -
TY - JOUR
A1 - Vetrivel, Sharmilee
A1 - Zhang, Ru
A1 - Engel, Mareen
A1 - Altieri, Barbara
A1 - Braun, Leah
A1 - Osswald, Andrea
A1 - Bidlingmaier, Martin
A1 - Fassnacht, Martin
A1 - Beuschlein, Felix
A1 - Reincke, Martin
A1 - Chen, Alon
A1 - Sbiera, Silviu
A1 - Riester, Anna
T1 - Circulating microRNA Expression in Cushing’s Syndrome
JF - Frontiers in Endocrinology
N2 - Context
Cushing’s syndrome (CS) is a rare disease of endogenous hypercortisolism associated with high morbidity and mortality. Diagnosis and classification of CS is still challenging.
Objective
Circulating microRNAs (miRNAs) are minimally invasive diagnostic markers. Our aim was to characterize the circulating miRNA profiles of CS patients and to identify distinct profiles between the two major CS subtypes.
Methods
We included three groups of patients from the German Cushing’s registry: ACTH-independent CS (Cortisol-Producing-Adenoma; CPA), ACTH-dependent pituitary CS (Cushing’s Disease; CD), and patients in whom CS had been ruled out (controls). Profiling of miRNAs was performed by next-generation-sequencing (NGS) in serum samples of 15 CS patients (each before and after curative surgery) and 10 controls. Significant miRNAs were first validated by qPCR in the discovery cohort and then in an independent validation cohort of 20 CS patients and 11 controls.
Results
NGS identified 411 circulating miRNAs. Differential expression of 14 miRNAs were found in the pre- and postoperative groups. qPCR in the discovery cohort validated 5 of the significant miRNAs from the preoperative group analyses. Only, miR-182-5p was found to be significantly upregulated in the CD group of the validation cohort. Comparing all CS samples as a group with the controls did not reveal any significant differences in expression.
Outcome
In conclusion, our study identified miR-182-5p as a possible biomarker for CD, which has to be validated in a prospective cohort. Furthermore, our results suggest that presence or absence of ACTH might be at least as relevant for miRNA expression as hypercortisolism itself.
KW - cortisol
KW - ACTH
KW - miRNA
KW - biomarker
KW - cortisol-producing adenoma
KW - miR-182-5p
KW - hypercortisolism
KW - miR-183 cluster
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229761
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Winter, Patrick M.
A1 - Andelovic, Kristina
A1 - Kampf, Thomas
A1 - Hansmann, Jan
A1 - Jakob, Peter Michael
A1 - Bauer, Wolfgang Rudolf
A1 - Zernecke, Alma
A1 - Herold, Volker
T1 - Simultaneous measurements of 3D wall shear stress and pulse wave velocity in the murine aortic arch
JF - Journal of Cardiovascular Magnetic Resonance
N2 - Purpose
Wall shear stress (WSS) and pulse wave velocity (PWV) are important parameters to characterize blood flow in the vessel wall. Their quantification with flow-sensitive phase-contrast (PC) cardiovascular magnetic resonance (CMR), however, is time-consuming. Furthermore, the measurement of WSS requires high spatial resolution, whereas high temporal resolution is necessary for PWV measurements. For these reasons, PWV and WSS are challenging to measure in one CMR session, making it difficult to directly compare these parameters. By using a retrospective approach with a flexible reconstruction framework, we here aimed to simultaneously assess both PWV and WSS in the murine aortic arch from the same 4D flow measurement.
Methods
Flow was measured in the aortic arch of 18-week-old wildtype (n = 5) and ApoE\(^{−/−}\) mice (n = 5) with a self-navigated radial 4D-PC-CMR sequence. Retrospective data analysis was used to reconstruct the same dataset either at low spatial and high temporal resolution (PWV analysis) or high spatial and low temporal resolution (WSS analysis). To assess WSS, the aortic lumen was labeled by semi-automatically segmenting the reconstruction with high spatial resolution. WSS was determined from the spatial velocity gradients at the lumen surface. For calculation of the PWV, segmentation data was interpolated along the temporal dimension. Subsequently, PWV was quantified from the through-plane flow data using the multiple-points transit-time method. Reconstructions with varying frame rates and spatial resolutions were performed to investigate the influence of spatiotemporal resolution on the PWV and WSS quantification.
Results
4D flow measurements were conducted in an acquisition time of only 35 min. Increased peak flow and peak WSS values and lower errors in PWV estimation were observed in the reconstructions with high temporal resolution. Aortic PWV was significantly increased in ApoE\(^{−/−}\) mice compared to the control group (1.7 ± 0.2 versus 2.6 ± 0.2 m/s, p < 0.001). Mean WSS magnitude values averaged over the aortic arch were (1.17 ± 0.07) N/m\(^2\) in wildtype mice and (1.27 ± 0.10) N/m\(^2\) in ApoE\(^{−/−}\) mice.
Conclusion
The post processing algorithm using the flexible reconstruction framework developed in this study permitted quantification of global PWV and 3D-WSS in a single acquisition. The possibility to assess both parameters in only 35 min will markedly improve the analyses and information content of in vivo measurements.
KW - 4D flow
KW - pulse wave velocity
KW - wall shear stress
KW - radial
KW - self-navigation
KW - mouse
KW - aortic arch
KW - atherosclerosis
KW - mice
KW - flow
KW - plaque
KW - CMR
KW - quantification
KW - microscopy
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259152
VL - 23
IS - 1
ER -
TY - JOUR
A1 - Hock, Michael
A1 - Terekhov, Maxim
A1 - Stefanescu, Maria Roxana
A1 - Lohr, David
A1 - Herz, Stefan
A1 - Reiter, Theresa
A1 - Ankenbrand, Markus
A1 - Kosmala, Aleksander
A1 - Gassenmaier, Tobias
A1 - Juchem, Christoph
A1 - Schreiber, Laura Maria
T1 - B\(_{0}\) shimming of the human heart at 7T
JF - Magnetic Resonance in Medicine
N2 - Purpose
Inhomogeneities of the static magnetic B\(_{0}\) field are a major limiting factor in cardiac MRI at ultrahigh field (≥ 7T), as they result in signal loss and image distortions. Different magnetic susceptibilities of the myocardium and surrounding tissue in combination with cardiac motion lead to strong spatio‐temporal B\(_{0}\)‐field inhomogeneities, and their homogenization (B0 shimming) is a prerequisite. Limitations of state‐of‐the‐art shimming are described, regional B\(_{0}\) variations are measured, and a methodology for spherical harmonics shimming of the B\(_{0}\) field within the human myocardium is proposed.
Methods
The spatial B\(_{0}\)‐field distribution in the heart was analyzed as well as temporal B\(_{0}\)‐field variations in the myocardium over the cardiac cycle. Different shim region‐of‐interest selections were compared, and hardware limitations of spherical harmonics B\(_{0}\) shimming were evaluated by calibration‐based B0‐field modeling. The role of third‐order spherical harmonics terms was analyzed as well as potential benefits from cardiac phase–specific shimming.
Results
The strongest B\(_{0}\)‐field inhomogeneities were observed in localized spots within the left‐ventricular and right‐ventricular myocardium and varied between systolic and diastolic cardiac phases. An anatomy‐driven shim region‐of‐interest selection allowed for improved B\(_{0}\)‐field homogeneity compared with a standard shim region‐of‐interest cuboid. Third‐order spherical harmonics terms were demonstrated to be beneficial for shimming of these myocardial B\(_{0}\)‐field inhomogeneities. Initial results from the in vivo implementation of a potential shim strategy were obtained. Simulated cardiac phase–specific shimming was performed, and a shim term‐by‐term analysis revealed periodic variations of required currents.
Conclusion
Challenges in state‐of‐the‐art B\(_{0}\) shimming of the human heart at 7 T were described. Cardiac phase–specific shimming strategies were found to be superior to vendor‐supplied shimming.
KW - 7 T
KW - B
KW - cardiac MRI
KW - shimming
KW - ultrahigh field
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218096
VL - 85
IS - 1
SP - 182
EP - 196
ER -
TY - JOUR
A1 - Liu, Dan
A1 - Hu, Kai
A1 - Lau, Kolja
A1 - Kiwitz, Tobias
A1 - Robitzkat, Katharina
A1 - Hammel, Clara
A1 - Lengenfelder, Björn Daniel
A1 - Ertl, Georg
A1 - Frantz, Stefan
A1 - Nordbeck, Peter
T1 - Impact of diastolic dysfunction on outcome in heart failure patients with mid-range or reduced ejection fraction
JF - ESC Heart Failure
N2 - Aims
The role of diastolic dysfunction (DD) in prognostic evaluation in heart failure (HF) patients with impaired systolic function remains unclear. We investigated the impact of echocardiography-defined DD on survival in HF patients with mid-range (HFmrEF, EF 41–49%) and reduced ejection fraction (HFrEF, EF < 40%).
Methods and results
A total of 2018 consecutive hospitalized HF patients were retrospectively included and divided in two groups based on baseline EF: HFmrEF group (n = 951, aged 69 ± 13 years, 74.2% male) and HFrEF group (n = 1067, aged 68 ± 13 years, 76.3% male). Clinical data were collected and analysed. All patients completed ≥1 year clinical follow-up. The primary endpoint was defined as all-cause death (including heart transplantation) and cardiovascular (CV)-related death. All-cause mortality (30.8% vs. 24.9%, P = 0.003) and CV mortality (19.1% vs. 13.5%, P = 0.001) were significantly higher in the HFrEF group than the HFmrEF group during follow-up [median 24 (13–36) months]. All-cause mortality increased in proportion to DD severity (mild, moderate, and severe) in either HFmrEF (17.1%, 25.4%, and 37.0%, P < 0.001) or HFrEF (18.9%, 30.3%, and 39.2%, P < 0.001) patients. The risk of all-cause mortality [hazard ratio (HR) = 1.347, P = 0.015] and CV mortality (HR = 1.508, P = 0.007) was significantly higher in HFrEF patients with severe DD compared with non-severe DD after adjustment for identified clinical and echocardiographic covariates. For HFmrEF patients, severe DD was independently associated with increased all-cause mortality (HR = 1.358, P = 0.046) but not with CV mortality (HR = 1.155, P = 0.469).
Conclusions
Echocardiography-defined severe DD is independently associated with increased all-cause mortality in patients with HFmrEF and HFrEF.
KW - heart failure with mid-range ejection fraction
KW - heart failure with reduced ejection fraction
KW - diastolic dysfunction
KW - echocardiography
KW - prognosis
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258894
VL - 8
IS - 4
ER -
TY - JOUR
A1 - Brodehl, Andreas
A1 - Meshkov, Alexey
A1 - Myasnikov, Roman
A1 - Kiseleva, Anna
A1 - Kulikova, Olga
A1 - Klauke, Bärbel
A1 - Sotnikova, Evgeniia
A1 - Stanasiuk, Caroline
A1 - Divashuk, Mikhail
A1 - Pohl, Greta Marie
A1 - Kudryavtseva, Maria
A1 - Klingel, Karin
A1 - Gerull, Brenda
A1 - Zharikova, Anastasia
A1 - Gummert, Jan
A1 - Koretskiy, Sergey
A1 - Schubert, Stephan
A1 - Mershina, Elena
A1 - Gärtner, Anna
A1 - Pilus, Polina
A1 - Laser, Kai Thorsten
A1 - Sinitsyn, Valentin
A1 - Boytsov, Sergey
A1 - Drapkina, Oxana
A1 - Milting, Hendrik
T1 - Hemi- and homozygous loss-of-function mutations in DSG2 (desmoglein-2) cause recessive arrhythmogenic cardiomyopathy with an early onset
JF - International Journal of Molecular Sciences
N2 - About 50% of patients with arrhythmogenic cardiomyopathy (ACM) carry a pathogenic or likely pathogenic mutation in the desmosomal genes. However, there is a significant number of patients without positive familial anamnesis. Therefore, the molecular reasons for ACM in these patients are frequently unknown and a genetic contribution might be underestimated. Here, we used a next-generation sequencing (NGS) approach and in addition single nucleotide polymor-phism (SNP) arrays for the genetic analysis of two independent index patients without familial medical history. Of note, this genetic strategy revealed a homozygous splice site mutation (DSG2–c.378+1G>T) in the first patient and a nonsense mutation (DSG2–p.L772X) in combination with a large deletion in DSG2 in the second one. In conclusion, a recessive inheritance pattern is likely for both cases, which might contribute to the hidden medical history in both families. This is the first report about these novel loss-of-function mutations in DSG2 that have not been previously identi-fied. Therefore, we suggest performing deep genetic analyses using NGS in combination with SNP arrays also for ACM index patients without obvious familial medical history. In the future, this finding might has relevance for the genetic counseling of similar cases.
KW - desmoglein-2
KW - desmocollin-2
KW - DSG2
KW - DSC2
KW - ARVC
KW - ACM
KW - LVNC
KW - cardiomyopathy
KW - desmosomes
KW - desmin
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285279
SN - 1422-0067
VL - 22
IS - 7
ER -
TY - JOUR
A1 - Morbach, Caroline
A1 - Beyersdorf, Niklas
A1 - Kerkau, Thomas
A1 - Ramos, Gustavo
A1 - Sahiti, Floran
A1 - Albert, Judith
A1 - Jahns, Roland
A1 - Ertl, Georg
A1 - Angermann, Christiane E.
A1 - Frantz, Stefan
A1 - Hofmann, Ulrich
A1 - Störk, Stefan
T1 - Adaptive anti-myocardial immune response following hospitalization for acute heart failure
JF - ESC Heart Failure
N2 - Aims
It has been hypothesized that cardiac decompensation accompanying acute heart failure (AHF) episodes generates a pro-inflammatory environment boosting an adaptive immune response against myocardial antigens, thus contributing to progression of heart failure (HF) and poor prognosis. We assessed the prevalence of anti-myocardial autoantibodies (AMyA) as biomarkers reflecting adaptive immune responses in patients admitted to the hospital for AHF, followed the change in AMyA titres for 6 months after discharge, and evaluated their prognostic utility.
Methods and results
AMyA were determined in n = 47 patients, median age 71 (quartiles 60; 80) years, 23 (49%) female, and 24 (51%) with HF with preserved ejection fraction, from blood collected at baseline (time point of hospitalization) and at 6 month follow-up (visit F6). Patients were followed for 18 months (visit F18). The prevalence of AMyA increased from baseline (n = 21, 45%) to F6 (n = 36, 77%; P < 0.001). At F6, the prevalence of AMyA was higher in patients with HF with preserved ejection fraction (n = 21, 88%) compared with patients with reduced ejection fraction (n = 14, 61%; P = 0.036). During the subsequent 12 months after F6, that is up to F18, patients with newly developed AMyA at F6 had a higher risk for the combined endpoint of death or rehospitalization for HF (hazard ratio 4.79, 95% confidence interval 1.13–20.21; P = 0.033) compared with patients with persistent or without AMyA at F6.
Conclusions
Our results support the hypothesis that AHF may induce patterns of adaptive immune responses. More studies in larger populations and well-defined patient subgroups are needed to further clarify the role of the adaptive immune system in HF progression.
KW - adaptive immune response
KW - acute heart failure
KW - anti-myocardial
KW - autoantibody
KW - inflammation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258907
VL - 8
IS - 4
ER -
TY - JOUR
A1 - Yurdadogan, Tino
A1 - Malsch, Carolin
A1 - Kotseva, Kornelia
A1 - Wood, David
A1 - Leyh, Rainer
A1 - Ertl, Georg
A1 - Karmann, Wolfgang
A1 - Müller-Scholden, Lara
A1 - Morbach, Caroline
A1 - Breuning, Margret
A1 - Wagner, Martin
A1 - Gelbrich, Götz
A1 - Bots, Michiel L.
A1 - Heuschmann, Peter U.
A1 - Störk, Stefan
T1 - Functional versus morphological assessment of vascular age in patients with coronary heart disease
JF - Scientific Reports
N2 - Communicating cardiovascular risk based on individual vascular age (VA) is a well acknowledged concept in patient education and disease prevention. VA may be derived functionally, e.g. by measurement of pulse wave velocity (PWV), or morphologically, e.g. by assessment of carotid intima-media thickness (cIMT). The purpose of this study was to investigate whether both approaches produce similar results. Within the context of the German subset of the EUROASPIRE IV survey, 501 patients with coronary heart disease underwent (a) oscillometric PWV measurement at the aortic, carotid-femoral and brachial-ankle site (PWVao, PWVcf, PWVba) and derivation of the aortic augmentation index (AIao); (b) bilateral cIMT assessment by high-resolution ultrasound at three sites (common, bulb, internal). Respective VA was calculated using published equations. According to VA derived from PWV, most patients exhibited values below chronological age indicating a counterintuitive healthier-than-anticipated vascular status: for VA(PWVao) in 68% of patients; for VA\(_{AIao}\) in 52% of patients. By contrast, VA derived from cIMT delivered opposite results: e.g. according to VA\(_{total-cIMT}\) accelerated vascular aging in 75% of patients. To strengthen the concept of VA, further efforts are needed to better standardise the current approaches to estimate VA and, thereby, to improve comparability and clinical utility.
KW - arterial stiffening
KW - atherosclerosis
KW - calcification
KW - carotid artery disease
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265810
VL - 11
IS - 1
ER -
TY - THES
A1 - Fischer, Gregor
T1 - Navigations- und Ultraschallgestützte Punktion der Leistenarterie beim transfemoralen Aortenklappenersatz
T1 - Navigation- and Ultrasound-guided puncture of the femoral artery in Transcatheter Aortic Valve Replacement
N2 - Transcatheter aortic valve replacement (TAVR) is an established procedure for treatment of aortic stenosis. In transfemoral TAVR local vascular complications at the puncture site are still an important issue and responsible for the majority of complications. To ensure safe puncture in a non-calcified vessel segment a new navigation technique with ultrasound guidance has been developed. We compared 67 consecutive patients undergoing TAVR using our new approach with 67 patients with fluoroscopic punction.
N2 - Die Transkatheter-Aortenklappenimplantation (TAVI) ist eine etablierte Prozedur zur Therapie der Aortenklappenstenose. Bei der transfemoralen TAVI sind Gefäßkomplikationen am Punktionsort weiterhin ein Problem und verantwortlich für einen Hauptteil der Komplikationen. Um eine sichere Punktion in einem nicht-kalzifizierten Gefäßabschnitt sicherzustellen, wurde eine neue Navigationstechnik mit Ultraschallunterstützung verwendet. Wir verglichen 67 konsekutive TAVI-Patienten mit Navigations- und Ultraschall-gestützter Punktion der Leistenarterie mit 67 konsekutiven Patienten mit Fluoroskopischer Punktion.
KW - Aortenklappenersatz
KW - Ultraschall
KW - Punktion
KW - TAVI
KW - Navigation
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-231586
ER -
TY - JOUR
A1 - Marquardt, André
A1 - Landwehr, Laura-Sophie
A1 - Ronchi, Cristina L.
A1 - di Dalmazi, Guido
A1 - Riester, Anna
A1 - Kollmannsberger, Philip
A1 - Altieri, Barbara
A1 - Fassnacht, Martin
A1 - Sbiera, Silviu
T1 - Identifying New Potential Biomarkers in Adrenocortical Tumors Based on mRNA Expression Data Using Machine Learning
JF - Cancers
N2 - Simple Summary
Using a visual-based clustering method on the TCGA RNA sequencing data of a large adrenocortical carcinoma (ACC) cohort, we were able to classify these tumors in two distinct clusters largely overlapping with previously identified ones. As previously shown, the identified clusters also correlated with patient survival. Applying the visual clustering method to a second dataset also including benign adrenocortical samples additionally revealed that one of the ACC clusters is more closely located to the benign samples, providing a possible explanation for the better survival of this ACC cluster. Furthermore, the subsequent use of machine learning identified new possible biomarker genes with prognostic potential for this rare disease, that are significantly differentially expressed in the different survival clusters and should be further evaluated.
Abstract
Adrenocortical carcinoma (ACC) is a rare disease, associated with poor survival. Several “multiple-omics” studies characterizing ACC on a molecular level identified two different clusters correlating with patient survival (C1A and C1B). We here used the publicly available transcriptome data from the TCGA-ACC dataset (n = 79), applying machine learning (ML) methods to classify the ACC based on expression pattern in an unbiased manner. UMAP (uniform manifold approximation and projection)-based clustering resulted in two distinct groups, ACC-UMAP1 and ACC-UMAP2, that largely overlap with clusters C1B and C1A, respectively. However, subsequent use of random-forest-based learning revealed a set of new possible marker genes showing significant differential expression in the described clusters (e.g., SOAT1, EIF2A1). For validation purposes, we used a secondary dataset based on a previous study from our group, consisting of 4 normal adrenal glands and 52 benign and 7 malignant tumor samples. The results largely confirmed those obtained for the TCGA-ACC cohort. In addition, the ENSAT dataset showed a correlation between benign adrenocortical tumors and the good prognosis ACC cluster ACC-UMAP1/C1B. In conclusion, the use of ML approaches re-identified and redefined known prognostic ACC subgroups. On the other hand, the subsequent use of random-forest-based learning identified new possible prognostic marker genes for ACC.
KW - adrenocortical carcinoma
KW - in silico analysis
KW - machine learning
KW - bioinformatic clustering
KW - biomarker prediction
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246245
SN - 2072-6694
VL - 13
IS - 18
ER -
TY - JOUR
A1 - Detomas, Mario
A1 - Altieri, Barbara
A1 - Schlötelburg, Wiebke
A1 - Appenzeller, Silke
A1 - Schlaffer, Sven
A1 - Coras, Roland
A1 - Schirbel, Andreas
A1 - Wild, Vanessa
A1 - Kroiss, Matthias
A1 - Sbiera, Silviu
A1 - Fassnacht, Martin
A1 - Deutschbein, Timo
T1 - Case Report: Consecutive Adrenal Cushing’s Syndrome and Cushing’s Disease in a Patient With Somatic CTNNB1, USP8, and NR3C1 Mutations
JF - Frontiers in Endocrinology
N2 - The occurrence of different subtypes of endogenous Cushing’s syndrome (CS) in single individuals is extremely rare. We here present the case of a female patient who was successfully cured from adrenal CS 4 years before being diagnosed with Cushing’s disease (CD). The patient was diagnosed at the age of 50 with ACTH-independent CS and a left-sided adrenal adenoma, in January 2015. After adrenalectomy and histopathological confirmation of a cortisol-producing adrenocortical adenoma, biochemical hypercortisolism and clinical symptoms significantly improved. However, starting from 2018, the patient again developed signs and symptoms of recurrent CS. Subsequent biochemical and radiological workup suggested the presence of ACTH-dependent CS along with a pituitary microadenoma. The patient underwent successful transsphenoidal adenomectomy, and both postoperative adrenal insufficiency and histopathological workup confirmed the diagnosis of CD. Exome sequencing excluded a causative germline mutation but showed somatic mutations of the β-catenin protein gene (CTNNB1) in the adrenal adenoma, and of both the ubiquitin specific peptidase 8 (USP8) and the glucocorticoid receptor (NR3C1) genes in the pituitary adenoma. In conclusion, our case illustrates that both ACTH-independent and ACTH-dependent CS may develop in a single individual even without evidence for a common genetic background.
KW - Cushing’s syndrome
KW - Cushing’s disease
KW - hypercortisolism
KW - glucocorticoid excess
KW - USP8
KW - CTNNB1
KW - NR3C1
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244596
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Augustin, Anne Marie
A1 - Welsch, Stefan
A1 - Bley, Thorsten Alexander
A1 - Lopau, Kai
A1 - Kickuth, Ralph
T1 - Color-coded summation images in the evaluation of renal artery stenosis before and after percutaneous transluminal angioplasty
JF - BMC Medical Imaging
N2 - Background: Endovascular therapy is the gold standard in patients with hemodynamic relevant renal artery stenosis (RAS) resistant to medical therapy. The severity grading of the stenosis as well as the result assessment after endovascular approach is predominantly based on visible estimations of the anatomic appearance. We aim to investigate the application of color-coded DSA parameters to gain hemodynamic information during endovascular renal artery interventions and for the assessment of the procedures technical success.
Methods: We retrospectively evaluated 32 patients who underwent endovascular renal artery revascularization and applied color-coded summation imaging on selected monochromatic DSA images. The differences in time to peak (dTTP) of contrast enhancement in predefined anatomical measuring points were analyzed. Furthermore, differences in systolic blood pressure values (SBP) and serum creatinine were obtained. The value of underlying diabetes mellitus as a predictor for clinical outcome was assessed. Correlation analysis between the patients gender as well as the presence of diabetes mellitus and dTTP was performed.
Results: Endovascular revascularization resulted in statistically significant improvement in 4/7 regions of interest. Highly significant improvement of perfusion in terms of shortened TTP values could be found at the segmental artery level and in the intrastenotical segment (p<0.001), significant improvement prestenotical and in the apical renal parenchyma (p<0.05). In the other anatomic regions, differences revealed not to be significant. Differences between SBP and serum creatinine levels before and after the procedure were significant (p=0.004 and 0.0004). Patients ' gender as well as the presence of diabetes mellitus did not reveal to be predictors for the clinical success of the procedure. Furthermore, diabetes and gender did not show relevant correlation with dTTP in the parenchymal measuring points.
Conclusions: The supplementary use of color-coding DSA and the data gained from parametric images may provide helpful information in the evaluation of the procedures ' technical success. The segmental artery might be a particularly suitable vascular territory for analyzing differences in blood flow characteristics. Further studies with larger cohorts are needed to further confirm the diagnostic value of this technique.
KW - digital subtraction angiography
KW - color-coded
KW - endovascular
KW - renal artery
KW - PTA
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259086
VL - 21
IS - 1
ER -
TY - THES
A1 - Paul, Rebecca Theodora
T1 - Subjektive Krankheitswahrnehmung, Therapieadhärenz und Zufriedenheit mit erhaltenen Informationen bei Patienten mit chronischer Nebenniereninsuffizienz – Zusammenhang mit der Teilnahme an einer standardisierten Patientenschulung
T1 - Beliefs about glucocorticoid replacement therapy, medication adherence and satisfaction with information in patients with adrenal insufficiency – relation with a participation in the standardised education programme
N2 - Rezente Studien mit kleineren Fallzahlen offenbaren bei Patienten mit chronischer Nebenniereninsuffizienz eine sehr negative Krankheitswahrnehmung, große Ängste und Sorgen hinsichtlich der Substitutionstherapie mit Glucocorticoiden sowie eine geringe Therapieadhärenz.
Ziel der vorliegenden Beobachtungsstudie war es daher im Rahmen einer monozentrischen Querschnittstudie nebenniereninsuffiziente Patienten zu Therapieadhärenz, subjektiver Krankheits- und Glucocorticoidwahrnehmung und Zufriedenheit mit erhaltenen Informationen zu befragen. Zudem wurden erstmalig die Zusammenhänge zwischen der Teilnahme an einer standardisierten NNI-Schulung und oben genannten Aspekten im Rahmen einer multizentrischen Längschnittstudie untersucht.
Die Ergebnisse der Querschnittstudie zeichnen insgesamt ein deutlich positiveres Bild von der subjektiven Krankheits- und Therapiewahrnehmung als bisher in der Literatur beschrieben. Die subjektive Therapieadhärenz war hoch. Zudem waren Sorgen und Ängste hinsichtlich der Glucocorticoid-Substitution geringer ausgeprägt als erwartet. Nichtsdestotrotz ließ sich konkordant zu früheren Publikationen eine zum Teil sehr große Unzufriedenheit mit erhaltenen Informationen zu möglichen Problemen der Glucocorticoid-Substitution feststellen. Die Ergebnisse der Längschnittstudie deuten darauf hin, dass die standardisierte Patientenschulung ein geeignetes Instrument sein könnte, um die Zufriedenheit von Patienten mit NNI zu steigern, das Selbstmanagement zu stärken und gleichzeitig positiven Einfluss auf die Wahrnehmung der Substitutionstherapie nehmen könnte.
N2 - Recent studies in patients with chronic adrenal insufficiency revealed negative illness perceptions, strong concerns regarding glucocorticoid replacement and low medication adherence.
In order to further evaluate subjective medication adherence, illness and glucocorticoids perception and satisfaction with information, we conducted a cross-sectional study comprising a larger German sample size. Furthermore, as part of a longitudinal study we aimed at evaluating the relation between the above-mentioned aspects and participation in a standardised education programme.
The findings of the cross-sectional study show a more positive perception of adrenal insufficiency and glucocorticoid replacement as than previously described in literature. Self-reported medication adherence was high in this sample. Therapy-related concerns were considerably lower than previously described. Participants reported low satisfaction with the information they received about potential problems of glucocorticoid intake. The results of the longitudinal study indicate that the standardised education programme may be an adequate tool to enhance satisfaction with information, to strengthen the patients` self-management of adrenal insufficiency and to improve the patients` perception of glucocorticoid replacement
KW - Nebennierenrindeninsuffizienz
KW - Hypoadrenalismus
KW - Patientenschulungen
KW - Subjektive Krankheitswahrnehmung
KW - Therapieadhärenz
KW - Patientenzufriedenheit
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235522
ER -
TY - JOUR
A1 - Andelovic, Kristina
A1 - Winter, Patrick
A1 - Kampf, Thomas
A1 - Xu, Anton
A1 - Jakob, Peter Michael
A1 - Herold, Volker
A1 - Bauer, Wolfgang Rudolf
A1 - Zernecke, Alma
T1 - 2D Projection Maps of WSS and OSI Reveal Distinct Spatiotemporal Changes in Hemodynamics in the Murine Aorta during Ageing and Atherosclerosis
JF - Biomedicines
N2 - Growth, ageing and atherosclerotic plaque development alter the biomechanical forces acting on the vessel wall. However, monitoring the detailed local changes in wall shear stress (WSS) at distinct sites of the murine aortic arch over time has been challenging. Here, we studied the temporal and spatial changes in flow, WSS, oscillatory shear index (OSI) and elastic properties of healthy wildtype (WT, n = 5) and atherosclerotic apolipoprotein E-deficient (Apoe\(^{−/−}\), n = 6) mice during ageing and atherosclerosis using high-resolution 4D flow magnetic resonance imaging (MRI). Spatially resolved 2D projection maps of WSS and OSI of the complete aortic arch were generated, allowing the pixel-wise statistical analysis of inter- and intragroup hemodynamic changes over time and local correlations between WSS, pulse wave velocity (PWV), plaque and vessel wall characteristics. The study revealed converse differences of local hemodynamic profiles in healthy WT and atherosclerotic Apoe\(^{−/−}\) mice, and we identified the circumferential WSS as potential marker of plaque size and composition in advanced atherosclerosis and the radial strain as a potential marker for vascular elasticity. Two-dimensional (2D) projection maps of WSS and OSI, including statistical analysis provide a powerful tool to monitor local aortic hemodynamics during ageing and atherosclerosis. The correlation of spatially resolved hemodynamics and plaque characteristics could significantly improve our understanding of the impact of hemodynamics on atherosclerosis, which may be key to understand plaque progression towards vulnerability.
KW - atherosclerosis
KW - mouse
KW - 4D flow MRI
KW - aortic arch
KW - flow dynamics
KW - WSS
KW - mapping
KW - PWV
KW - plaque characteristics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-252164
SN - 2227-9059
VL - 9
IS - 12
ER -
TY - JOUR
A1 - Petri, Nils
A1 - Lengenfelder, Björn
A1 - Voelker, Wolfram
A1 - Nordbeck, Peter
T1 - Interventional closure of aortomitral perforation after TAVR: A case report
JF - Catheterization and Cardiovascular Interventions
N2 - Despite TAVR emerging as the gold standard for a broad spectrum of patients, it is associated with serious complications. In this report we present a case, where a TAVR procedure led to a perforation at the aortomitral continuity, discuss the risk factors for the occurrence of perforations and how we decided to treat the patient.
KW - medicine
KW - closure AV fistula/AVM (CLAV)
KW - transcatheter valveimplantation (TVI)
KW - percutaneous valve therapy (PVT)
KW - aortic valve disease percutaneous intervention (AVDP)
KW - imaging TTE/TEE (ITTE)
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256625
VL - 98
IS - 3
ER -
TY - JOUR
A1 - Sbiera, Iuliu
A1 - Kircher, Stefan
A1 - Altieri, Barbara
A1 - Lenz, Kerstin
A1 - Hantel, Constanze
A1 - Fassnacht, Martin
A1 - Sbiera, Silviu
A1 - Kroiss, Matthias
T1 - Role of FGF Receptors and Their Pathways in Adrenocortical Tumors and Possible Therapeutic Implications
JF - Frontiers in Endocrinology
N2 - Adrenocortical carcinoma (ACC) is a rare endocrine malignancy and treatment of advanced disease is challenging. Clinical trials with multi-tyrosine kinase inhibitors in the past have yielded disappointing results. Here, we investigated fibroblast growth factor (FGF) receptors and their pathways in adrenocortical tumors as potential treatment targets. We performed real-time RT-PCR of 93 FGF pathway related genes in a cohort of 39 fresh frozen benign and malignant adrenocortical, 9 non-adrenal tissues and 4 cell lines. The expression of FGF receptors was validated in 166 formalin-fixed paraffin embedded (FFPE) tissues using RNA in situ hybridization (RNAscope) and correlated with clinical data. In malignant compared to benign adrenal tumors, we found significant differences in the expression of 16/94 FGF receptor pathway related genes. Genes involved in tissue differentiation and metastatic spread through epithelial to mesechymal transition were most strongly altered. The therapeutically targetable FGF receptors 1 and 4 were upregulated 4.6- and 6-fold, respectively, in malignant compared to benign adrenocortical tumors, which was confirmed by RNAscope in FFPE samples. High expression of FGFR1 and 4 was significantly associated with worse patient prognosis in univariate analysis. After multivariate adjustment for the known prognostic factors Ki-67 and ENSAT tumor stage, FGFR1 remained significantly associated with recurrence-free survival (HR=6.10, 95%CI: 1.78 – 20.86, p=0.004) and FGFR4 with overall survival (HR=3.23, 95%CI: 1.52 – 6.88, p=0.002). Collectively, our study supports a role of FGF pathways in malignant adrenocortical tumors. Quantification of FGF receptors may enable a stratification of ACC for the use of FGFR inhibitors in future clinical trials.
KW - normal adrenal glands
KW - adrenocortical tumors
KW - FGF-pathway
KW - FGFR
KW - RNA Expression
KW - RNAScope
KW - unsupervised clustering
KW - patient survival
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-251953
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Dischinger, Ulrich
A1 - Hasinger, Julia
A1 - Königsrainer, Malina
A1 - Corteville, Carolin
A1 - Otto, Christoph
A1 - Fassnacht, Martin
A1 - Hankir, Mohamed
A1 - Seyfried, Florian Johannes David
T1 - Toward a Medical Gastric Bypass: Chronic Feeding Studies With Liraglutide + PYY\(_{3-36}\) Combination Therapy in Diet-Induced Obese Rats
JF - Frontiers in Endocrinology
N2 - Background
Combination therapies of anorectic gut hormones partially mimic the beneficial effects of bariatric surgery. Thus far, the effects of a combined chronic systemic administration of Glucagon-like peptide-1 (GLP-1) and peptide tyrosine tyrosine 3-36 (PYY\(_{3-36}\)) have not been directly compared to Roux-en-Y gastric bypass (RYGB) in a standardized experimental setting.
Methods
High-fat diet (HFD)-induced obese male Wistar rats were randomized into six treatment groups: (1) RYGB, (2) sham-operation (shams), (3) liraglutide, (4) PYY\(_{3-36}\), (5) PYY\(_{3-36}\)+liraglutide (6), saline. Animals were kept on a free choice high- and low-fat diet. Food intake, preference, and body weight were measured daily for 4 weeks. Open field (OP) and elevated plus maze (EPM) tests were performed.
Results
RYGB reduced food intake and achieved sustained weight loss. Combined PYY\(_{3-36}\)+liraglutide treatment led to similar and plateaued weight loss compared to RYGB. Combined PYY\(_{3-36}\)+liraglutide treatment was superior to PYY\(_{3-36}\) (p ≤ 0.0001) and liraglutide (p ≤ 0.05 or p ≤ 0.01) mono-therapy. PYY\(_{3-36}\)+liraglutide treatment and RYGB also reduced overall food intake and (less pronounced) high-fat preference compared to controls. The animals showed no signs of abnormal behavior in OF or EPM.
Conclusions
Liraglutide and PYY\(_{3-36}\) combination therapy vastly mimics reduced food intake, food choice and weight reducing benefits of RYGB.
KW - obesity
KW - rygb
KW - liraglutide
KW - peptide tyrosine tyrosine (PYY)
KW - treatment
KW - gastric bypass
KW - peptide tyrosine tyrosine 3-36 (PYY3-36)
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-223113
SN - 1664-2392
VL - 11
ER -
TY - JOUR
A1 - Haring, Bernhard
A1 - Reiner, Alexander P.
A1 - Liu, Jungmin
A1 - Tobias, Deirdre K.
A1 - Whitsel, Eric
A1 - Berger, Jeffrey S.
A1 - Desai, Pinkal
A1 - Wassertheil-Smoller, Sylvia
A1 - LaMonte, Michael J.
A1 - Hayden, Kathleen
A1 - Bick, Alexander G.
A1 - Natarajan, Pradeep
A1 - Weinstock, Joshua S.
A1 - Nguyen, Patricia K.
A1 - Stefanick, Marcia
A1 - Simon, Michael S.
A1 - Eaton, Charles
A1 - Kooperberg, Charles
A1 - Manson, JoAnn E.
T1 - Healthy Lifestyle and Clonal Hematopoiesis of Indeterminate Potential. Results from the Women’s Health Initiative
JF - Journal of the American Heart Association
N2 - Background
Presence of clonal hematopoiesis of indeterminate potential (CHIP) is associated with a higher risk of atherosclerotic cardiovascular disease, cancer, and mortality. The relationship between a healthy lifestyle and CHIP is unknown.
Methods and Results
This analysis included 8709 postmenopausal women (mean age, 66.5 years) enrolled in the WHI (Women's Health Initiative), free of cancer or cardiovascular disease, with deep‐coverage whole genome sequencing data available. Information on lifestyle factors (body mass index, smoking, physical activity, and diet quality) was obtained, and a healthy lifestyle score was created on the basis of healthy criteria met (0 point [least healthy] to 4 points [most healthy]). CHIP was derived on the basis of a prespecified list of leukemogenic driver mutations. The prevalence of CHIP was 8.6%. A higher healthy lifestyle score was not associated with CHIP (multivariable‐adjusted odds ratio [OR] [95% CI], 0.99 [0.80–1.23] and 1.13 [0.93–1.37]) for the upper (3 or 4 points) and middle category (2 points), respectively, versus referent (0 or 1 point). Across score components, a normal and overweight body mass index compared with obese was significantly associated with a lower odds for CHIP (OR, 0.71 [95% CI, 0.57–0.88] and 0.83 [95% CI, 0.68–1.01], respectively; P‐trend 0.0015). Having never smoked compared with being a current smoker tended to be associated with lower odds for CHIP.
Conclusions
A healthy lifestyle, based on a composite score, was not related to CHIP among postmenopausal women. However, across individual lifestyle factors, having a normal body mass index was strongly associated with a lower prevalence of CHIP. These findings support the idea that certain healthy lifestyle factors are associated with a lower frequency of CHIP.
KW - body mass index
KW - clonal hematopoiesis of indeterminate potential
KW - diet
KW - lifestyle
KW - physical activity
KW - smoking
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236146
VL - 10
IS - 5
ER -
TY - JOUR
A1 - Traub, Jan
A1 - Husseini, Leila
A1 - Weber, Martin S.
T1 - B cells and antibodies as targets of therapeutic intervention in neuromyelitis optica spectrum disorders
JF - Pharmaceuticals
N2 - The first description of neuromyelitis optica by Eugène Devic and Fernand Gault dates back to the 19th century, but only the discovery of aquaporin-4 autoantibodies in a major subset of affected patients in 2004 led to a fundamentally revised disease concept: Neuromyelits optica spectrum disorders (NMOSD) are now considered autoantibody-mediated autoimmune diseases, bringing the pivotal pathogenetic role of B cells and plasma cells into focus. Not long ago, there was no approved medication for this deleterious disease and off-label therapies were the only treatment options for affected patients. Within the last years, there has been a tremendous development of novel therapies with diverse treatment strategies: immunosuppression, B cell depletion, complement factor antagonism and interleukin-6 receptor blockage were shown to be effective and promising therapeutic interventions. This has led to the long-expected official approval of eculizumab in 2019 and inebilizumab in 2020. In this article, we review current pathogenetic concepts in NMOSD with a focus on the role of B cells and autoantibodies as major contributors to the propagation of these diseases. Lastly, by highlighting promising experimental and future treatment options, we aim to round up the current state of knowledge on the therapeutic arsenal in NMOSD.
KW - neuromyelitis optica spectrum disorders
KW - B cells
KW - antibodies
KW - eculizumab
KW - ravulizumab
KW - inebilizumab
KW - tocilizumab
KW - satralizumab
KW - ublituximab
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222957
SN - 1424-8247
VL - 14
IS - 1
ER -
TY - JOUR
A1 - Chen, Menjia
A1 - Liu, Dan
A1 - Weidemann, Frank
A1 - Lengenfelder, Björn Daniel
A1 - Ertl, Georg
A1 - Hu, Kai
A1 - Frantz, Stefan
A1 - Nordbeck, Peter
T1 - Echocardiographic risk factors of left ventricular thrombus in patients with acute anterior myocardial infarction
JF - ESC Heart Failure
N2 - Aims
This study aimed to identify echocardiographic determinants of left ventricular thrombus (LVT) formation after acute anterior myocardial infarction (MI).
Methods and results
This case–control study comprised 55 acute anterior MI patients with LVT as cases and 55 acute anterior MI patients without LVT as controls, who were selected from a cohort of consecutive patients with ischemic heart failure in our hospital. The cases and controls were matched for age, sex, and left ventricular ejection fraction. LVT was detected by routine/contrast echocardiography or cardiac magnetic resonance imaging during the first 3 months following MI. Formation of apical aneurysm after MI was independently associated with LVT formation [72.0% vs. 43.5%, odds ratio (OR) = 5.06, 95% confidence interval (CI) 1.65–15.48, P = 0.005]. Echocardiographic risk factors associated with LVT formation included reduced mitral annular plane systolic excursion (<7 mm, OR = 4.69, 95% CI 1.84–11.95, P = 0.001), moderate–severe diastolic dysfunction (OR = 2.71, 95% CI 1.11–6.57, P = 0.028), and right ventricular (RV) dysfunction [reduced tricuspid annular plane systolic excursion < 17 mm (OR = 5.48, 95% CI 2.12–14.13, P < 0.001), reduced RV fractional area change < 0.35 (OR = 3.32, 95% CI 1.20–9.18, P = 0.021), and enlarged RV mid diameter (per 5 mm increase OR = 1.62, 95% CI 1.12–2.34, P = 0.010)]. Reduced tricuspid annular plane systolic excursion (<17 mm) significantly associated with increased risk of LVT in anterior MI patients (OR = 3.84, 95% CI 1.37–10.75, P = 0.010), especially in those patients without apical aneurysm (OR = 5.12, 95% CI 1.45–18.08, P = 0.011), independent of body mass index, hypertension, anaemia, mitral annular plane systolic excursion, and moderate–severe diastolic dysfunction.
Conclusions
Right ventricular dysfunction as determined by reduced TAPSE or RV fractional area change is independently associated with LVT formation in acute anterior MI patients, especially in the setting of MI patients without the formation of an apical aneurysm. This study suggests that besides assessment of left ventricular abnormalities, assessment of concomitant RV dysfunction is of importance on risk stratification of LVT formation in patients with acute anterior MI.
KW - myocardial infarction
KW - aneurysm
KW - left ventricular thrombusv
KW - right ventricular dysfunction
KW - echocardiography
KW - cardiovascular magnetic resonance
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-261067
VL - 8
IS - 6
ER -
TY - JOUR
A1 - Adam, Pia
A1 - Kircher, Stefan
A1 - Sbiera, Iuliu
A1 - Koehler, Viktoria Florentine
A1 - Berg, Elke
A1 - Knösel, Thomas
A1 - Sandner, Benjamin
A1 - Fenske, Wiebke Kristin
A1 - Bläker, Hendrik
A1 - Smaxwil, Constantin
A1 - Zielke, Andreas
A1 - Sipos, Bence
A1 - Allelein, Stephanie
A1 - Schott, Matthias
A1 - Dierks, Christine
A1 - Spitzweg, Christine
A1 - Fassnacht, Martin
A1 - Kroiss, Matthias
T1 - FGF-Receptors and PD-L1 in Anaplastic and Poorly Differentiated Thyroid Cancer: Evaluation of the Preclinical Rationale
JF - Frontiers in Endocrinology
N2 - Background
Treatment options for poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinoma are unsatisfactory and prognosis is generally poor. Lenvatinib (LEN), a multi-tyrosine kinase inhibitor targeting fibroblast growth factor receptors (FGFR) 1-4 is approved for advanced radioiodine refractory thyroid carcinoma, but response to single agent is poor in ATC. Recent reports of combining LEN with PD-1 inhibitor pembrolizumab (PEM) are promising.
Materials and Methods
Primary ATC (n=93) and PDTC (n=47) tissue samples diagnosed 1997-2019 at five German tertiary care centers were assessed for PD-L1 expression by immunohistochemistry using Tumor Proportion Score (TPS). FGFR 1-4 mRNA was quantified in 31 ATC and 14 PDTC with RNAscope in-situ hybridization. Normal thyroid tissue (NT) and papillary thyroid carcinoma (PTC) served as controls. Disease specific survival (DSS) was the primary outcome variable.
Results
PD-L1 TPS≥50% was observed in 42% of ATC and 26% of PDTC specimens. Mean PD-L1 expression was significantly higher in ATC (TPS 30%) than in PDTC (5%; p<0.01) and NT (0%, p<0.001). 53% of PDTC samples had PD-L1 expression ≤5%. FGFR mRNA expression was generally low in all samples but combined FGFR1-4 expression was significantly higher in PDTC and ATC compared to NT (each p<0.001). No impact of PD-L1 and FGFR 1-4 expression was observed on DSS.
Conclusion
High tumoral expression of PD-L1 in a large proportion of ATCs and a subgroup of PDTCs provides a rationale for immune checkpoint inhibition. FGFR expression is low thyroid tumor cells. The clinically observed synergism of PEM with LEN may be caused by immune modulation.
KW - tyrosine kinase inhibitor (TKI)
KW - immune checkpoint inhibitor (ICI)
KW - immunohistochemistry
KW - immunotherapy
KW - PD-L1
KW - FGFR
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244653
SN - 1664-2392
VL - 12
ER -