@article{CapetianMuellerVolkmannetal.2020, author = {Capetian, Philipp and M{\"u}ller, Lorenz and Volkmann, Jens and Heckmann, Manfred and Erg{\"u}n, S{\"u}leyman and Wagner, Nicole}, title = {Visualizing the synaptic and cellular ultrastructure in neurons differentiated from human induced neural stem cells - an optimized protocol}, series = {International Journal of Molecular Sciences}, volume = {21}, journal = {International Journal of Molecular Sciences}, number = {5}, issn = {1422-0067}, doi = {10.3390/ijms21051708}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236053}, year = {2020}, abstract = {The size of the synaptic subcomponents falls below the limits of visible light microscopy. Despite new developments in advanced microscopy techniques, the resolution of transmission electron microscopy (TEM) remains unsurpassed. The requirements of tissue preservation are very high, and human post mortem material often does not offer adequate quality. However, new reprogramming techniques that generate human neurons in vitro provide samples that can easily fulfill these requirements. The objective of this study was to identify the culture technique with the best ultrastructural preservation in combination with the best embedding and contrasting technique for visualizing neuronal elements. Two induced neural stem cell lines derived from healthy control subjects underwent differentiation either adherent on glass coverslips, embedded in a droplet of highly concentrated Matrigel, or as a compact neurosphere. Afterward, they were fixed using a combination of glutaraldehyde (GA) and paraformaldehyde (PFA) followed by three approaches (standard stain, Ruthenium red stain, high contrast en-bloc stain) using different combinations of membrane enhancing and contrasting steps before ultrathin sectioning and imaging by TEM. The compact free-floating neurospheres exhibited the best ultrastructural preservation. High-contrast en-bloc stain offered particularly sharp staining of membrane structures and the highest quality visualization of neuronal structures. In conclusion, compact neurospheres growing under free-floating conditions in combination with a high contrast en-bloc staining protocol, offer the optimal preservation and contrast with a particular focus on visualizing membrane structures as required for analyzing synaptic structures.}, language = {en} } @article{HollenhorstJurastowNandigamaetal.2020, author = {Hollenhorst, Monika I. and Jurastow, Innokentij and Nandigama, Rajender and Appenzeller, Silke and Li, Lei and Vogel, J{\"o}rg and Wiederhold, Stephanie and Althaus, Mike and Empting, Martin and Altm{\"u}ller, Janine and Hirsch, Anna K. H. and Flockerzi, Veit and Canning, Brendan J. and Saliba, Antoine-Emmanuel and Krasteva-Christ, Gabriela}, title = {Tracheal brush cells release acetylcholine in response to bitter tastants for paracrine and autocrine signaling}, series = {The FASEB Journal}, volume = {34}, journal = {The FASEB Journal}, number = {1}, doi = {10.1096/fj.201901314RR}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-213516}, pages = {316 -- 332}, year = {2020}, abstract = {For protection from inhaled pathogens many strategies have evolved in the airways such as mucociliary clearance and cough. We have previously shown that protective respiratory reflexes to locally released bacterial bitter "taste" substances are most probably initiated by tracheal brush cells (BC). Our single-cell RNA-seq analysis of murine BC revealed high expression levels of cholinergic and bitter taste signaling transcripts (Tas2r108, Gnat3, Trpm5). We directly demonstrate the secretion of acetylcholine (ACh) from BC upon stimulation with the Tas2R agonist denatonium. Inhibition of the taste transduction cascade abolished the increase in [Ca\(^{2+}\)]\(_{i}\) in BC and subsequent ACh-release. ACh-release is regulated in an autocrine manner. While the muscarinic ACh-receptors M3R and M1R are activating, M2R is inhibitory. Paracrine effects of ACh released in response to denatonium included increased [Ca\(^{2+}\)]\(_{i}\) in ciliated cells. Stimulation by denatonium or with Pseudomonas quinolone signaling molecules led to an increase in mucociliary clearance in explanted tracheae that was Trpm5- and M3R-mediated. We show that ACh-release from BC via the bitter taste cascade leads to immediate paracrine protective responses that can be boosted in an autocrine manner. This mechanism represents the initial step for the activation of innate immune responses against pathogens in the airways.}, language = {en} } @article{Gottschlich2020, author = {Gottschlich, G{\"u}nter}, title = {Synopse der f{\"u}r Deutschland nachgewiesenen Arten und Unterarten der Gattung Hieracium s. l. (Hieracium s. str. und Pilosella), aufgeschl{\"u}sselt nach Vorkommen in den einzelnen Bundesl{\"a}ndern}, series = {Forum geobotanicum}, volume = {9}, journal = {Forum geobotanicum}, issn = {1867-9315}, doi = {10.3264/FG.2020.0114}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-198175}, pages = {1-59}, year = {2020}, abstract = {Eine Liste der 205 Arten und 1561 Unterarten der Gattung Hieracium s. l. , die in Deutschland, aufgeschl{\"u}sselt nach Bundesl{\"a}ndern vorkommen, wird vorgestellt. Da die meisten infraspezifischen Namen unter Hieracium publiziert wurden und um die Zahl der invaliden Namen unter Pilosella in der Liste zu minimieren, wird auf eine Aufteilung in Hieracium und Pilosella verzichtet. Durch Farbmarkierungen wird gekennzeichnet, welche Unterart urspr{\"u}nglich aus einem Bundesland beschrieben wurde bzw. ob ein Syntypus aus einem Bundesland stammt.}, subject = {Habichtskraut}, language = {de} } @phdthesis{Kwok2020, author = {Kwok, Chee Keong}, title = {Scaling up production of reprogrammed cells for biomedical applications}, doi = {10.25972/OPUS-19186}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191865}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Induced pluripotent stem cells (iPSCs) have been recognised as a virtually unlimited source of stem cells that can be generated in a patient-specific manner. Due to these cells' potential to give rise to all differentiated cell types of the human body, they have been widely used to derive differentiated cells for drug screening and disease modelling purposes. iPSCs also garner much interest as they can potentially serve as a source for cell replacement therapy. Towards the realisation of these biomedical applications, this thesis aims to address challenges that are associated with scale-up, safety and biofabrication. Firstly, the manufacture of a high number of human iPSCs (hiPSCs) will require standardised procedures for scale-up and the development of a flexible bioprocessing method, since standard adherent hiPSC culture exhibits limited scalability and is labour-intensive. While the quantity of cells that are required for cell therapy depends largely on the tissue and defect that these replacing cells are meant to correct, an estimate of 1 × 10^9 has been suggested to be sufficient for several indications, including myocardial infarction and islet replacement for diabetes. Here, the development of an integrated, microcarrier-free workflow to transition standard adherent hiPSC culture (6-well plates) to scalable stirred suspension culture in bioreactors (1 L working volume, 2.4 L maximum working volume) is presented. The two-phase bioprocess lasts 14 days and generates hiPSC aggregates measuring 198 ± 58 μm in diameter on the harvesting day, yielding close to 2 × 10^9 cells. hiPSCs can be maintained in stirred suspension for at least 7 weeks with weekly passaging, while exhibiting pluripotency-associated markers TRA-1-60, TRA-1-81, SSEA-4, OCT4, and SOX2. These cells retain their ability to differentiate into cells of all the three germ layers in vitro, exemplified by cells positive for AFP, SMA, or TUBB3. Additionally, they maintain a stable karyotype and continue to respond to specification cues, demonstrated by directed differentiation into beating cardiomyocyte-like cells. Therefore, the aim of manufacturing high hiPSC quantities was met using a state-of-the-art scalable suspension bioreactor platform. Secondly, multipotent stem cells such as induced neural stem cells (iNSCs) may represent a safer source of renewable cells compared to pluripotent stem cells. However, pre-conditioning of stem cells prior to transplantation is a delicate issue to ensure not only proper function in the host but also safety. Here, iNSCs which are normally maintained in the presence of factors such as hLIF, CHIR99021, and SB431542 were cultured in basal medium for distinct periods of time. This wash-out procedure results in lower proliferation while maintaining key neural stem cell marker PAX6, suggesting a transient pre-differentiated state. Such pre-treatment may aid transplantation studies to suppress tumourigenesis through transplanted cells, an approach that is being evaluated using a mouse model of experimental focal demyelination and autoimmune encephalomyelitis. Thirdly, biomedical applications of stem cells can benefit from recent advancements in biofabrication, where cells can be arranged in customisable topographical layouts. Employing a 3DDiscovery bioprinter, a bioink consisting of hiPSCs in gelatin-alginate was extruded into disc-shaped moulds or printed in a cross-hatch infill pattern and cross-linked with calcium ions. In both discs and printed patterns, hiPSCs recovered from these bioprints showed viability of around 70\% even after 4 days of culture when loaded into gelatin-alginate solution in aggregate form. They maintained pluripotency-associated markers TRA-1-60 and SSEA-4 and continued to proliferate after re-plating. As further proof-of-principle, printed hiPSC 3D constructs were subjected to targeted neuronal differentiation, developing typical neurite outgrowth and resulting in a widespread network of cells throughout and within the topology of the printed matrix. Staining against TUBB3 confirmed neuronal identity of the differentiated cellular progeny. In conclusion, these data demonstrate that hiPSCs not only survive the 3D-printing process but were able to differentiate along the printed topology in cellular networks.}, subject = {scale-up}, language = {en} } @article{IUedaWoersdoerferetal.2020, author = {I, Takashi and Ueda, Yuichiro and W{\"o}rsd{\"o}rfer, Philipp and Sumita, Yoshinori and Asahina, Izumi and Erg{\"u}n, S{\"u}leyman}, title = {Resident CD34-positive cells contribute to peri-endothelial cells and vascular morphogenesis in salivary gland after irradiation}, series = {Journal of Neural Transmission}, volume = {127}, journal = {Journal of Neural Transmission}, issn = {0300-9564}, doi = {10.1007/s00702-020-02256-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235613}, pages = {1467-1479}, year = {2020}, abstract = {Salivary gland (SG) hypofunction is a common post-radiotherapy complication. Besides the parenchymal damage after irradiation (IR), there are also effects on mesenchymal stem cells (MSCs) which were shown to contribute to regeneration and repair of damaged tissues by differentiating into stromal cell types or releasing vesicles and soluble factors supporting the healing processes. However, there are no adequate reports about their roles during SG damage and regeneration so far. Using an irradiated SG mouse model, we performed certain immunostainings on tissue sections of submandibular glands at different time points after IR. Immunostaining for CD31 revealed that already one day after IR, vascular impairment was induced at the level of capillaries. In addition, the expression of CD44—a marker of acinar cells—diminished gradually after IR and, by 20 weeks, almost disappeared. In contrast, the number of CD34-positive cells significantly increased 4 weeks after IR and some of the CD34-positive cells were found to reside within the adventitia of arteries and veins. Laser confocal microscopic analyses revealed an accumulation of CD34-positive cells within the area of damaged capillaries where they were in close contact to the CD31-positive endothelial cells. At 4 weeks after IR, a fraction of the CD34-positive cells underwent differentiation into α-SMA-positive cells, which suggests that they may contribute to regeneration of smooth muscle cells and/or pericytes covering the small vessels from the outside. In conclusion, SG-resident CD34-positive cells represent a population of progenitors that could contribute to new vessel formation and/or remodeling of the pre-existing vessels after IR and thus, might be an important player during SG tissue healing.}, language = {en} } @article{Dunkel2020, author = {Dunkel, Franz G.}, title = {Ranunculus sarntheinianus Dunkel, spec. nova, eine neue Art aus dem Ranunculus-auricomus-Komplex - seit 135 Jahren im Oberen Inntal bei Innsbruck}, series = {Forum geobotanicum}, volume = {9}, journal = {Forum geobotanicum}, issn = {1867-9315}, doi = {10.3264/FG.2020.0115}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-198183}, pages = {60-65}, year = {2020}, abstract = {F{\"u}r das Vorkommen einer Ranunculus auricomus-Sippe im Oberen Inntal bei Innnsbuck, Nordtirol, {\"O}sterreich, existieren belegte Nachweise seit 135 Jahren. Diese Sippe sammelte L. Sarnthein am 08.06.1884, J. Murr 1887 bei Flaurling. Von beiden Aufsammlungen befinden sich Belege im Tiroler Landesmuseum (Herbarium Ferdinandeum Innsbruck; IBF). Trotz Trockenlegung der Sumpfwiesen und Eutrophierung des Biotops kommt die Art noch aktuell in einem kleinen Nasswiesenrest vor. Sie wird hier als R. sarntheinianus Dunkel beschrieben, abgebildet und ihre Taxonomie wird diskutiert. Der mutmaßlich letzte Wuchsort ist vom Aussterben bedroht. Eine graphische Darstellung soll bei Artbestimmung und Auffinden neuer Wuchsorte behilflich sein.}, subject = {Hahnenfuß}, language = {de} } @article{Gallo2020, author = {Gallo, Lorenzo}, title = {Nomenclatural adjustments and typifications in the genus Phedimus (Crassulaceae)}, series = {Forum Geobotanicum}, volume = {9}, journal = {Forum Geobotanicum}, issn = {1867-9315}, doi = {10.3264/FG.2020.0616}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-206347}, pages = {70-73}, year = {2020}, abstract = {This paper deals with the taxonomical position and the nomenclature of two taxa belonging to the genus Sedum (Crassulaceae), today treated as Phedimus, namely Sedum middendorffianum Maxim var. diffusum Praeger and Sedum oppositifolium Sims. The correct taxonomical application of names is based on the nomenclatural types designated here.}, subject = {Sedum oppositifolium}, language = {en} } @article{Koepsell2020, author = {Koepsell, Hermann}, title = {Glucose transporters in the small intestine in health and disease}, series = {Pfl{\"u}gers Archiv - European Journal of Physiology}, volume = {472}, journal = {Pfl{\"u}gers Archiv - European Journal of Physiology}, issn = {0031-6768}, doi = {10.1007/s00424-020-02439-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232552}, pages = {1207-1248}, year = {2020}, abstract = {Absorption of monosaccharides is mainly mediated by Na\(^+\)-d-glucose cotransporter SGLT1 and the facititative transporters GLUT2 and GLUT5. SGLT1 and GLUT2 are relevant for absorption of d-glucose and d-galactose while GLUT5 is relevant for d-fructose absorption. SGLT1 and GLUT5 are constantly localized in the brush border membrane (BBM) of enterocytes, whereas GLUT2 is localized in the basolateral membrane (BLM) or the BBM plus BLM at low and high luminal d-glucose concentrations, respectively. At high luminal d-glucose, the abundance SGLT1 in the BBM is increased. Hence, d-glucose absorption at low luminal glucose is mediated via SGLT1 in the BBM and GLUT2 in the BLM whereas high-capacity d-glucose absorption at high luminal glucose is mediated by SGLT1 plus GLUT2 in the BBM and GLUT2 in the BLM. The review describes functions and regulations of SGLT1, GLUT2, and GLUT5 in the small intestine including diurnal variations and carbohydrate-dependent regulations. Also, the roles of SGLT1 and GLUT2 for secretion of enterohormones are discussed. Furthermore, diseases are described that are caused by malfunctions of small intestinal monosaccharide transporters, such as glucose-galactose malabsorption, Fanconi syndrome, and fructose intolerance. Moreover, it is reported how diabetes, small intestinal inflammation, parental nutrition, bariatric surgery, and metformin treatment affect expression of monosaccharide transporters in the small intestine. Finally, food components that decrease d-glucose absorption and drugs in development that inhibit or downregulate SGLT1 in the small intestine are compiled. Models for regulations and combined functions of glucose transporters, and for interplay between d-fructose transport and metabolism, are discussed.}, language = {en} } @article{Koepsell2020, author = {Koepsell, Hermann}, title = {Glucose transporters in brain in health and disease}, series = {Pfl{\"u}gers Archiv - European Journal of Physiology}, volume = {472}, journal = {Pfl{\"u}gers Archiv - European Journal of Physiology}, issn = {0031-6768}, doi = {10.1007/s00424-020-02441-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232746}, pages = {1299-1343}, year = {2020}, abstract = {Energy demand of neurons in brain that is covered by glucose supply from the blood is ensured by glucose transporters incapillaries and brain cells. In brain, the facilitative diffusion glucose transporters GLUT1-6 and GLUT8, and the Na+-D-glucosecotransporters SGLT1 are expressed. The glucose transporters mediate uptake of D-glucose across the blood-brain barrier anddelivery of D-glucose to astrocytes and neurons. They are critically involved in regulatory adaptations to varying energy demandsin response to differing neuronal activities and glucose supply. In this review, a comprehensive overview about verified andproposed roles of cerebral glucose transporters during health and diseases is presented. Our current knowledge is mainly based onexperiments performed in rodents. First, the functional properties of human glucose transporters expressed in brain and theircerebral locations are described. Thereafter, proposed physiological functions of GLUT1, GLUT2, GLUT3, GLUT4, andSGLT1 for energy supply to neurons, glucose sensing, central regulation of glucohomeostasis, and feeding behavior are compiled, and their roles in learning and memory formation are discussed. In addition, diseases are described in which functionalchanges of cerebral glucose transporters are relevant. These are GLUT1 deficiency syndrome (GLUT1-SD), diabetes mellitus, Alzheimer's disease (AD), stroke, and traumatic brain injury (TBI). GLUT1-SD is caused by defect mutations in GLUT1. Diabetes and AD are associated with changed expression of glucose transporters in brain, and transporter-related energy defi-ciency of neurons may contribute to pathogenesis of AD. Stroke and TBI are associated with changes of glucose transporter expression that influence clinical outcome}, language = {en} } @misc{GottschlichDunkelDrenckhahnetal.2020, author = {Gottschlich, G{\"u}nter and Dunkel, Franz G. and Drenckhahn, Detlev and Weber, Heinrich E. and Gallo, Lorenzo}, title = {Forum Geobotanicum Vol. 9 (2020)}, volume = {9(2020)}, editor = {Meierott, Lenz and Drenckhahn, Detlev and Dunkel, Franz G. and Ewald, J{\"o}rg and Fleischmann, Andreas}, issn = {1867-9315}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-298919}, year = {2020}, abstract = {Forum Geobotanicum is an electronic journal devoted to disseminate information concerning geographical distribution, ecology, morphology, taxonomy and conservation of vascular plants in the European Union with a main focus on middle Europe. It covers from molecular biology to environmental aspects. The focus is to publish original papers, reviews and announcements for the educated generalist as well as the specialist in this broad field. Forum Geobotanicum does not aim to supplant existing paper journals, but will be much more flexible in format, publication time and world-wide distribution than paper journals. Many important studies are being currently published in local journals and booklets and some of them are published privately. Hence, these studies will become aware to only a limited readership. Forum Geobotanicum will encourage authors of such papers to submit them as special issues of the journal. Moreover, the journal is planning to build up an E-mail-address section to support communication between geobotanists in Europe. The editors are optimistic that this electronic journal will develop to a widely used communication forum that will help to stimulate activities in the entire field of geobotany in middle Europe. To overcome problems of long term archivation and effective taxonomic publication of articles published electronically in Forum Geobotanicum, print versions of each volume of the journal and appropriate digital storage devices will be delivered freely to selected university libraries and state libraries in middle Europe.}, subject = {Geobotanik}, language = {de} } @article{HenkeNandigamaErguen2020, author = {Henke, Erik and Nandigama, Rajender and Erg{\"u}n, S{\"u}leyman}, title = {Extracellular matrix in the tumor microenvironment and its impact on cancer therapy}, series = {Frontiers in Molecular Biosciences}, volume = {6}, journal = {Frontiers in Molecular Biosciences}, number = {160}, issn = {2296-889X}, doi = {10.3389/fmolb.2019.00160}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-199341}, year = {2020}, abstract = {Solid tumors are complex organ-like structures that consist not only of tumor cells but also of vasculature, extracellular matrix (ECM), stromal, and immune cells. Often, this tumor microenvironment (TME) comprises the larger part of the overall tumor mass. Like the other components of the TME, the ECM in solid tumors differs significantly from that in normal organs. Intratumoral signaling, transport mechanisms, metabolisms, oxygenation, and immunogenicity are strongly affected if not controlled by the ECM. Exerting this regulatory control, the ECM does not only influence malignancy and growth of the tumor but also its response toward therapy. Understanding the particularities of the ECM in solid tumor is necessary to develop approaches to interfere with its negative effect. In this review, we will also highlight the current understanding of the physical, cellular, and molecular mechanisms by which the pathological tumor ECM affects the efficiency of radio-, chemo-, and immunotherapy. Finally, we will discuss the various strategies to target and modify the tumor ECM and how they could be utilized to improve response to therapy.}, language = {en} } @phdthesis{Kleefeldt2020, author = {Kleefeldt, Florian}, title = {Einfluss von CEACAM1 auf die endotheliale Funktion}, doi = {10.25972/OPUS-20172}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201726}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Dem Endothel, welches die luminale Oberfl{\"a}che aller Blutgef{\"a}ße auskleidet, kommt eine wichtige Barrierefunktion zwischen Blut und Gewebe zu. Nur durch eine bedarfsgerechte Justierung dieser Barriere, die den Durchtritt von Molek{\"u}len und Zellen reguliert, kann die Gewebehom{\"o}ostase aufrechterhalten werden. Dabei ist das Endothel nicht nur passive Barriere, sondern auch an dieser dynamischen Regulation aktiv beteiligt. St{\"o}rungen oder Fehlregulationen dieser Prozesse f{\"u}hren zu Pathologien, z.B. Arteriosklerose. Es ist seit l{\"a}ngerem bekannt, dass Carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1), ein Mitglied der Immunglobulin-Superfamilie, die Bildung und Morphogenese neuer Blutgef{\"a}ße beeinflusst. Die spontane Entwicklung kleiner Arteriosklerose-{\"a}hnlicher L{\"a}sionen in CEACAM1 knockout (Cc1-/-) M{\"a}usen zeigt, dass CEACAM1 auch f{\"u}r die Hom{\"o}ostase ausgereifter Blutgef{\"a}ße von Bedeutung ist. Ziel dieser Dissertationsarbeit war daher, den Einfluss von CEACAM1 auf wesentliche Aspekte der Endothelfunktion in Aorten in situ bzw. in Endothelzellkulturen in vitro zu analysieren. Es konnte zun{\"a}chst gezeigt werden, dass CEACAM1-defiziente Endothelzellen im Vergleich zu Wildtyp (WT) Endothelzellen eine rundlichere Zellmorphologie mit meanderf{\"o}rmigen Zellgrenzen und interzellul{\"a}ren L{\"u}cken aufweisen. Diese morphologischen Unterschiede stimmen mit Befunden in situ an Aorten von WT und Cc1-/- M{\"a}usen {\"u}berein. Weiterhin wurde eine Translokation der endothelialen NO-Synthase (eNOS) von der Zellmembran in den peri-nukle{\"a}ren Bereich bei CEACAM1-Defizienz festgestellt. Die erhobenen Daten bieten zwei m{\"o}gliche Erkl{\"a}rungen daf{\"u}r. Einerseits k{\"o}nnte CEACAM1 durch Interaktion mit eNOS als Membrananker fungieren. Daneben wiesen CEACAM1-defiziente Endothelzellen eine erh{\"o}hte Expression des Enzyms APT1 auf, welches eNOS depalmitoyliert. Die daraus resultierende, ebenfalls nachgewiesene geringere Palmitoylierung k{\"o}nnte auch zur verminderten Membran-lokalisation von eNOS beitragen. Zur endothelialen Funktion geh{\"o}rt, die Adh{\"a}sion von Blutzellen an die Gef{\"a}ßwand weitestgehend zu beschr{\"a}nken. CEACAM1-defiziente Endothelzellen zeigten im Vergleich zu WT Endothelzellen eine verst{\"a}rkte Adh{\"a}sivit{\"a}t gegen{\"u}ber murinen und humanen Monozyten. {\"A}hnliche Unterschiede wurden f{\"u}r Aortenexplantate aus WT und Cc1-/- M{\"a}usen festgestellt. Dies ist einerseits mit einer verst{\"a}rkten Expression des Zelladh{\"a}sionsmolek{\"u}ls ICAM-1 bei CEACAM1-Defizienz erkl{\"a}rbar. Dar{\"u}ber hinaus vermittelt die Glykokalyx anti-adh{\"a}sive Eigenschaften. Aus Vorbefunden war bekannt, dass die endotheliale Glykokalyx in der Aorta von Cc1-/- M{\"a}use reduziert ist. Im Rahmen dieser Arbeit konnte dies auf eine verst{\"a}rkte Expression der Glykokalyx-degradierenden Enzyme MMP9, Chondroitinase sowie Hyaluronidase-2 in Cc1-/- Endothelzellen zur{\"u}ckgef{\"u}hrt werden. Eine erh{\"o}hte Permeabilit{\"a}t stellt einen Indikator f{\"u}r ein dysfunktionales Endothel, eines der initialen Schritte in der Pathogenese der Arteriosklerose, dar. Zur Analyse der aortalen Permeabilit{\"a}t wurde ein modifizierter Miles-Assay etabliert. Unter Verwendung etablierter muriner Arteriosklerosemodelle konnte gezeigt werden, dass dieser Assay eine St{\"o}rung der vaskul{\"a}ren Permeabilit{\"a}t bereits vor Auftreten makroskopischer Ver{\"a}nderungen zuverl{\"a}ssig detektiert. Im Rahmen der folgenden Analysen an WT und Cc1-/- M{\"a}usen zeigte sich ein altersabh{\"a}ngiger Effekt von CEACAM1 auf die Gef{\"a}ßpermeabilit{\"a}t: Aorten von 3 Monate alten Cc1-/- M{\"a}use wiesen eine im Vergleich zum WT erh{\"o}hte Gef{\"a}ßpermeabilit{\"a}t auf, welche wahrscheinlich Folge einer verz{\"o}gerten Gef{\"a}ßreifung ist. Im Alter von 9 Monaten zeigte sich dagegen ein entgegengesetztes Bild. Dies wurde auf eine verst{\"a}rkte Expression des die Barriere sch{\"a}digenden Inflammationsmediators TNF-α in 9 Monate alten WT M{\"a}usen zur{\"u}ckgef{\"u}hrt. Außerdem modulierte CEACAM1 die TNF-α-vermittelte Lockerung der endothelialen Barriere, indem es die Phosphorylierung von Adherens Junction Proteinen beeinflusste. Basal stabilisierte CEACAM1 die endotheliale Barriere durch Hemmung der Phosphorylierung von Caveolin-1, welches Adherens Junctions destabilisiert. Unter Einfluss von TNF-α war CEACAM1 verst{\"a}rkt im Bereich von Adherens Junctions lokalisiert und rekrutierte dort Src-Kinase. Src-Kinase wiederum destabilisierte Adherens Junctions durch Phosphorylierung von β-Catenin, was in verst{\"a}rkter Gef{\"a}ßpermeabilit{\"a}t resultierte. Dagegen f{\"u}hrte TNF-α in CEACAM1-defizienten Endothelzellen zu einer Dephosphorylierung von Caveolin-1 und β-Catenin, wodurch Adherens Junctions und damit die endotheliale Barriere stabilisiert wurden. Diese CEACAM1-abh{\"a}ngige differenzielle Regulation der Stabilit{\"a}t von Adherens Junctions unter TNF-α tr{\"a}gt wahrscheinlich maßgeblich zu den Unterschieden der vaskul{\"a}ren Permeabilit{\"a}t in 3 bzw. 9 Monate alten WT und Cc1-/- M{\"a}usen bei. Zusammenfassend konnte im Rahmen dieser Arbeit nachgewiesen werden, dass CEACAM1 zentrale Funktionen des Endothels und hier{\"u}ber die Hom{\"o}ostase reifer Gef{\"a}ße beeinflusst. Da eine Expression von CEACAM1 auch in arteriosklerotischen Plaques nachgewiesen werden konnte, soll in weiteren Untersuchungen auch der Beitrag von CEACAM1 zur arteriosklerotischen Plaquebildung analysiert werden.}, subject = {Endothel}, language = {de} } @article{WoersdoerferIAsahinaetal.2020, author = {W{\"o}rsd{\"o}rfer, Philipp and I, Takashi and Asahina, Izumi and Sumita, Yoshinori and Erg{\"u}n, S{\"u}leyman}, title = {Do not keep it simple: recent advances in the generation of complex organoids}, series = {Journal of Neural Transmission}, volume = {127}, journal = {Journal of Neural Transmission}, issn = {0300-9564}, doi = {10.1007/s00702-020-02198-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235628}, pages = {1569-1577}, year = {2020}, abstract = {3D cell culture models which closely resemble real human tissues are of high interest for disease modelling, drug screening as well as a deeper understanding of human developmental biology. Such structures are termed organoids. Within the last years, several human organoid models were described. These are usually stem cell derived, arise by self-organization, mimic mechanisms of normal tissue development, show typical organ morphogenesis and recapitulate at least some organ specific functions. Many tissues have been reproduced in vitro such as gut, liver, lung, kidney and brain. The resulting entities can be either derived from an adult stem cell population, or generated from pluripotent stem cells using a specific differentiation protocol. However, many organoid models only recapitulate the organs parenchyma but are devoid of stromal components such as blood vessels, connective tissue and inflammatory cells. Recent studies show that the incorporation of endothelial and mesenchymal cells into organoids improved their maturation and might be required to create fully functional micro-tissues, which will allow deeper insights into human embryogenesis as well as disease development and progression. In this review article, we will summarize and discuss recent works trying to incorporate stromal components into organoids, with a special focus on neural organoid models.}, language = {en} } @phdthesis{Muenster2020, author = {M{\"u}nster, Wienke}, title = {Die Rolle von Acetylcholin und cholinergem Signalling in der Angiogenese}, doi = {10.25972/OPUS-20740}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207408}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Ziel dieser Arbeit war die Untersuchung des Einflusses von ACh und vom cholinergen Signalling in der Angiogenese. Neben der klassischen Rolle des AChs im neuronalen System, konnten es in den letzten Jahren auch in nicht-neuronal innerviertem Gewebe festgestellt werden. In dieser Arbeit konzentrierte man sich auf beobachtete cholinerge Zellen in der Aortenwand einer ChAT-eGFP-Maus und in davon ausgehenden neu gebildeten Gef{\"a}ßen. Nach Durchf{\"u}hrung des Aortenringassays nach Baker konnte zun{\"a}chst nachgewiesen werden, dass es sich bei ACh um einen Angiogenese-Stimulator handelt. Eine Carbacholkonzentration von 1 µM erwies sich als bester Angiogenesestimulator. Der Inhibitorversuch mit Lenvatinib, einem Hemmer des VEGFR, zeigte, dass die cholinerge Wirkung zur Aktivierung {\"a}hnlicher angiogeneseseinhibierenden Mechanismen wie bei einer VEGF-Stimulation kommt. Bei der zeitlichen Weiterverfolgung des Versuchs konnte man feststellen, dass sich die Gef{\"a}ßformation mit Dauer des Versuches {\"a}ndert. Bei der immunhistologischen Analyse der neu gebildeten Gef{\"a}ße wurde am ehesten eine {\"U}berlappung der ChAT-Zellen mit Zellen gefunden, die sich positiv f{\"u}r die Perizytenmarker NG2 und Desmin zeigten. Es ist anzunehmen, dass das ACh, exprimiert von einigen Perizyten, eine Leitschiene f{\"u}r das sich neu bildende Gef{\"a}ß bietet und zu einem gerichteten Wachstum f{\"u}hrt. Vor Kurzem wurde in der Wand erwachsener Blutgef{\"a}ße eine Nische f{\"u}r Stammzellen identifiziert. Um zu untersuchen ob die ChAT-Zellen dort ihren Ursprung haben, wurde mit Stammzellmarkern gef{\"a}rbt. Diese Arbeit hat mit ihren Ergebnissen eine signifikante Grundlage f{\"u}r weiterf{\"u}hrende Studien geliefert.}, subject = {Acetylcholin}, language = {de} } @phdthesis{Burow2020, author = {Burow, Wera Tamara}, title = {Die Rolle des CEACAM1-Molek{\"u}ls bei der Entstehung von neurogener Entz{\"u}ndung in den Atemwegen}, doi = {10.25972/OPUS-20933}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-209331}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Neurogene Entz{\"u}ndung ist charakterisiert durch Vasodilatation, Plasmaextravasation und Leukozytenmigration. Im Zuge dieser Dissertationsarbeit konnte ein in vivo Versuchsmodell zur Quantifizierung neurogener Entz{\"u}ndungsreaktionen in den Atemwegen etabliert werden. Der bakterielle Bitterstoff Cycloheximid ist in der Lage, eine Erh{\"o}hung der Plasmaextravasation und Migration neutrophiler Granulozyten zu bewirken. Somit kann Cycloheximid nicht nur protektive Schutzreflexe ausl{\"o}sen, sondern f{\"u}hrt auch lokal zu einer neurogenen Entz{\"u}ndungsreaktion. Das carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1) ist an der Regulierung der endothelialen Barrierefunktion beteiligt. Die Versuche zeigen bei CC1-/--M{\"a}usen eine Verminderung der basalen Permeabilit{\"a}t in trachealen postkapill{\"a}ren Venolen. Nach Stimulation mit Cycloheximid zeigen CC1-/--M{\"a}use im Vergleich mit WT-M{\"a}usen eine verminderte Plasmaextravasation in bronchialen postkapill{\"a}ren Venolen. Auch die Permeabilit{\"a}t des Endothels f{\"u}r neutrophile Granulozyten scheint durch CEACAM1-Defizienz in trachealen und bronchialen Venolen herabgesetzt zu werden. Die Anwesenheit des CEACAM1-Molek{\"u}ls verursacht offenbar eine verminderte Stabilit{\"a}t der endothelialen Barriere in postkapill{\"a}ren Venolen der Atemwege. Diese Ergebnisse zeigen eine gegenteilige Funktion von CEACAM1 in postkapill{\"a}ren Venolen der Atemwege im Vergleich mit großen, herznahen Blutgef{\"a}ßen. Des Weiteren scheint sich die Rolle von CEACAM1 in der Entstehung von akuten und chronischen Entz{\"u}ndungsreaktionen zu unterscheiden. Das in dieser Arbeit etablierte Versuchsmodell stellt eine M{\"o}glichkeit dar, neurogene Entz{\"u}ndungsreaktionen als Reaktion auf verschiedene gustatorische Stimulanzien zu testen und zu quantifizieren.}, subject = {Entz{\"u}ndung}, language = {de} } @article{DrenckhahnWeber2020, author = {Drenckhahn, Detlev and Weber, Heinrich E.}, title = {Die Nordfriesische Brombeere, Rubus boreofrisicus Drenckhahn \& H. E. Weber, eine endemische Rubus-Art der Westk{\"u}ste von Schleswig-Holstein, Deutschland}, series = {Forum geobotanicum}, volume = {9}, journal = {Forum geobotanicum}, issn = {1867-9315}, doi = {10.3264/FG.2020.0116}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-198194}, pages = {66-69}, year = {2020}, abstract = {Rubus boreofrisicus Drenckhahn \& H. E.Weber ist eine bisher unbeschriebene Rubus-Art der Untergattung Rubus, Serie Discolores. Die Endbl{\"a}ttchen der 5-z{\"a}hligen, handf{\"o}rmigen Sch{\"o}sslingsbl{\"a}tter sind breit eif{\"o}rmig bis ann{\"a}hernd rund, unterseits grau-weißlich, oberseits dunkelgr{\"u}n und schwach behaart. Die Sch{\"o}sslinge sind braunrot, kantig bis schwach gefurcht, etwas behaart mit geraden bis schwach gekr{\"u}mmten, 5-8 mm langen, braunroten Stacheln mit heller Spitzenh{\"a}lfte. Die Bl{\"u}tenstiele besitzen Stieldr{\"u}sen. Rubus boreofrisicus kommt h{\"a}ufig im Waldg{\"u}rtel und in der angrenzenden D{\"u}nenheide der nordfriesischen Insel Amrum vor und ist auch 50 km s{\"u}dlich von Amrum in St. Peter-Ording im Westen der Halbinsel Eiderstedt vertreten.}, subject = {Rubus}, language = {de} } @phdthesis{Eckner2020, author = {Eckner, Georg Ludwig}, title = {Der Einfluss vaskul{\"a}r-adventitieller Makrophagen auf Gef{\"a}ßwand-residente Stammzellen}, doi = {10.25972/OPUS-20608}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-206080}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {In dieser Dissertation wurden murine Aorta-Explantate im experimentellen Ansatz des "Aortic Ring Assay" {\"u}ber elf Tage kultiviert, erstmalig die Differenzierung zu F4/80(+)-Makrophagen gezeigt und eine nahezu vollst{\"a}ndige Depletion dieser Zellen durch Clodronat-Liposomen bewirkt. Diese Adventitia-generierten Makrophagen wurden als die Hauptquelle des lokal gebildeten VEGF nachgewiesen. Die daraus resultierende Depletion des parakrin wirkenden VEGF resultierte in einer teilweisen Konservierung der CD34(+) „Vaskulogenen Zone" der aortalen Adventitia. Zu der Best{\"a}tigung dieser Ergebnisse wurde experimentell {\"u}ber den VEGF-Rezeptor-Blocker E7080 in das VEGF-VEGFR-2 System eingegriffen. Die Versuchsans{\"a}tze mit diesem Rezeptorblocker resultierten in einem {\"a}hnlichen Ergebnis wie die Versuche unter Makrophagen-Depletion.}, subject = {Gef{\"a}ßwand}, language = {de} } @phdthesis{Huebner2020, author = {H{\"u}bner, Lisa-Christina}, title = {Bedeutung von neuroendokrinen Zellen f{\"u}r die Signal{\"u}bertragung an sensorischen Nervenfasern in den Atemwegen}, doi = {10.25972/OPUS-20751}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207517}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Die vorliegende Arbeit hatte zum Ziel, neuroendokrine Zellen in den Atemwegen bei M{\"a}usen zu untersuchen, welche Kontakt zu sensorischen Nervenfasern ausbilden. In vorangegangenen Versuchen konnte bereits die Menge des ausgesch{\"u}tteten CGRPs nach Stimulation mit Bitterstoffen bestimmt werden. Die Methode zur Messung der Freisetzung von CGRP aus verschiedenen Organen wurde von Prof. Reeh und seiner Arbeitsgruppe etabliert. Ziel der vorliegenden Arbeit war es, zu untersuchen, woher das ausgesch{\"u}ttete CGRP kommt und ob die Stimulation von B{\"u}rstenzellen mit Bitterstoffen zur Aussch{\"u}ttung von CGRP aus den neuroendokrinen Zellen f{\"u}hrt. Anhand der elektronenmikroskopischen Auswertung und der dreidimensionalen Rekonstruktion konnte gezeigt werden, dass es Kontakt zwischen den neuroendokrinen Zellen im Epithel der Trachea und sensorischen Nervenfasern gibt. Die immunhistochemischen Versuche zeigten, dass es nach Stimulation mit Denatonium h{\"o}chstwahrscheinlich zur Aussch{\"u}ttung von CGRP durch die intraepithelialen Fasern gekommen ist. Diese Annahme spiegelt sich in der ver{\"a}nderten Morphologie sowie der geringeren Quantit{\"a}t der intraepithelialen Fasern nach Stimulation mit Denatonium deutlich wider. Dass es weder bei der Anzahl der neuroendokrinen Zellen, noch bei der Erscheinung und Anzahl der extraepithelialen Fasern nach Denatoniumstimulation zu einer Ver{\"a}nderung gekommen ist, unterst{\"u}tzt diese Annahme ebenfalls. Im Hinblick auf die durchgef{\"u}hrten Versuche mit den TRPM5-gendefizienten M{\"a}usen zeigte sich, dass die Stimulation mit Denatonium keine Auswirkungen auf die Anzahl der neuroendokrinen Zellen hatte. Dieses Ergebnis unterst{\"u}tzt die Erkenntnisse der vorangegangenen Untersuchungen, welche gezeigt haben, dass das CGRP nicht von den neuroendokrinen Zellen ausgesch{\"u}ttet wurde. Des Weiteren l{\"a}sst das Ergebnis darauf schließen, dass die Aussch{\"u}ttung von CGRP nicht abh{\"a}ngig von der Anwesenheit von B{\"u}rstenzellen ist. Insgesamt zeigen die Untersuchungen, dass es nach Stimulation mit Bittersubstanzen zu einer CGRP-Aussch{\"u}ttung durch die intraepithelialen Fasern gekommen ist. Interessant w{\"a}re es weiterhin zu kl{\"a}ren, welche Effekte diese Aussch{\"u}ttung bewirkt und welche Bedeutung der Freisetzung von Substanz P in diesem Zusammenhang zukommt.}, subject = {Luftr{\"o}hre}, language = {de} } @article{OttoFriedrichMadunićetal.2020, author = {Otto, Christoph and Friedrich, Alexandra and Madunić, Ivana Vrhovac and Baumeier, Christian and Schwenk, Robert W. and Karaica, Dean and Germer, Christoph-Thomas and Sch{\"u}rmann, Annette and Sabolić, Ivan and Koepsell, Hermann, Hermann}, title = {Antidiabetic Effects of a Tripeptide That Decreases Abundance of Na\(^+\)-D-glucose Cotransporter SGLT1 in the Brush-Border Membrane of the Small Intestine}, series = {ACS Omega}, volume = {5}, journal = {ACS Omega}, number = {45}, doi = {10.1021/acsomega.0c03844}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230654}, pages = {29127-29139}, year = {2020}, abstract = {In enterocytes, protein RS1 (RSC1A1) mediates an increase of glucose absorption after ingestion of glucose-rich food via upregulation of Na+-D-glucose cotransporter SGLT1 in the brush-border membrane (BBM). Whereas RS1 decelerates the exocytotic pathway of vesicles containing SGLT1 at low glucose levels between meals, RS1-mediated deceleration is relieved after ingestion of glucose-rich food. Regulation of SGLT1 is mediated by RS1 domain RS1-Reg, in which Gln-Ser-Pro (QSP) is effective. In contrast to QSP and RS1-Reg, Gln-Glu-Pro (QEP) and RS1-Reg with a serine to glutamate exchange in the QSP motif downregulate the abundance of SGLT1 in the BBM at high intracellular glucose concentrations by about 50\%. We investigated whether oral application of QEP improves diabetes in db/db mice and affects the induction of diabetes in New Zealand obese (NZO) mice under glucolipotoxic conditions. After 6-day administration of drinking water containing 5 mM QEP to db/db mice, fasting glucose was decreased, increase of blood glucose in the oral glucose tolerance test was blunted, and insulin sensitivity was increased. When QEP was added for several days to a high fat/high carbohydrate diet that induced diabetes in NZO mice, the increase of random plasma glucose was prevented, accompanied by lower plasma insulin levels. QEP is considered a lead compound for development of new antidiabetic drugs with more rapid cellular uptake. In contrast to SGLT1 inhibitors, QEP-based drugs may be applied in combination with insulin for the treatment of type 1 and type 2 diabetes, decreasing the required insulin amount, and thereby may reduce the risk of hypoglycemia.}, language = {en} } @article{GrunzWenigKunzetal.2020, author = {Grunz, Jan-Peter and Wenig, Andreas Max and Kunz, Andreas Steven and Veyhl-Wichmann, Maike and Schmitt, Rainer and Gietzen, Carsten Herbert and Pennig, Lenhard and Herz, Stefan and Erg{\"u}n, S{\"u}leyman and Bley, Thorsten Alexander and Gassenmaier, Tobias}, title = {3D cone-beam CT with a twin robotic x-ray system in elbow imaging: comparison of image quality to high-resolution multidetector CT}, series = {European Radiology Experimental}, volume = {4}, journal = {European Radiology Experimental}, doi = {10.1186/s41747-020-00177-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229877}, year = {2020}, abstract = {Background Elbow imaging is challenging with conventional multidetector computed tomography (MDCT), while cone-beam CT (CBCT) provides superior options. We compared intra-individually CBCT versus MDCT image quality in cadaveric elbows. Methods A twin robotic x-ray system with new CBCT mode and a high-resolution clinical MDCT were compared in 16 cadaveric elbows. Both systems were operated with a dedicated low-dose (LD) protocol (equivalent volume CT dose index [CTDI\(_{vol(16 cm)}\)] = 3.3 mGy) and a regular clinical scan dose (RD) protocol (CTDI\(_{vol(16 cm)}\) = 13.8 mGy). Image quality was evaluated by two radiologists (R1 and R2) on a seven-point Likert scale, and estimation of signal intensity in cancellous bone was conducted. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) statistics were used. Results The CBCT prototype provided superior subjective image quality compared to MDCT scans (for RD, p ≤ 0.004; for LD, p ≤ 0.001). Image quality was rated very good or excellent in 100\% of the cases by both readers for RD CBCT, 100\% (R1) and 93.8\% (R2) for LD CBCT, 62.6\% and 43.8\% for RD MDCT, and 0.0\% and 0.0\% for LD MDCT. Single-measure ICC was 0.95 (95\% confidence interval 0.91-0.97; p < 0.001). Software-based assessment supported subjective findings with less "undecided" pixels in CBCT than dose-equivalent MDCT (p < 0.001). No significant difference was found between LD CBCT and RD MDCT. Conclusions In cadaveric elbow studies, the tested cone-beam CT prototype delivered superior image quality compared to high-end multidetector CT and showed a potential for considerable dose reduction.}, language = {en} }