19 research outputs found
Birds Kept in the German Zoo "Tierpark Berlin" Are a Common Source for Polyvalent Yersinia pseudotuberculosis Phages
Yersinia pseudotuberculosis is an important animal pathogen, particularly for birds, rodents, and monkeys, which is also able to infect humans. Indeed, an increasing number of reports have been published on zoo animals that were killed by this species. One option to treat diseased animals is the application of strictly lytic (virulent) phages. However, thus far relatively few phages infecting Y. pseudotuberculosis have been isolated and characterized. To determine the prevalence of Y. pseudotuberculosis phages in zoo animals, fecal samples of birds and some primates, maras, and peccaries kept in the Tierpark Berlin were analyzed. Seventeen out of 74 samples taken in 2013 and 2017 contained virulent phages. The isolated phages were analyzed in detail and could be allocated to three groups. The first group is composed of 10 T4-like phages (PYps2T taxon group: Myoviridae; Tevenvirinae; Tequatrovirus), the second group (PYps23T taxon group: Chaseviridae; Carltongylesvirus; Escherichia virus ST32) consists of five phages encoding a podovirus-like RNA polymerase that is related to an uncommon genus of myoviruses (e.g., Escherichia coli phage phiEcoM-GJ1), while the third group is comprised of two podoviruses (PYps50T taxon group: Autographiviridae; Studiervirinae; Berlinvirus) which are closely related to T7. The host range of the isolated phages differed significantly. Between 5.5 and 86.7% of 128 Y. pseudotuberculosis strains belonging to 20 serotypes were lysed by each phage. All phages were additionally able to lyse Y. enterocolitica B4/O:3 strains, when incubated at 37 degrees C. Some phages also infected Y. pestis strains and even strains belonging to other genera of Enterobacteriaceae. A cocktail containing two of these phages would be able to lyse almost 93% of the tested Y. pseudotuberculosis strains. The study indicates that Y. pseudotuberculosis phages exhibiting a broad-host range can be isolated quite easily from zoo animals, particularly birds.Peer reviewe
Unterhaltungsqualität und Public Value
Gebühren finanzierte TV Sender haben die Aufgabe Public Value zu schaffen. In der Regel umfasst der Leistungsauftrag dabei sowohl Information und Bildung als auch Unterhaltung. Während sich für informierende und bildende Inhalte relativ leicht feststellen lässt, worin der Nutzen für die Öffentlichkeit besteht, ist dies für die Unterhaltung weniger eindeutig. An dieser Stelle setzt der Beitrag an. Es wird argumentiert, dass der Public Value von Unterhaltung von der Qualität der Unterhaltung abhängt. Hierfür muss zunächst geklärt werden, an welchen Kriterien sich die Qualität von Unterhaltung festmachen lässt. Die Qualität stellt sich vielschichtig dar, es müssen unterschiedliche Perspektiven z.B. von Rezipienten, Produzenten und Regulierern berücksichtigt werden. Auf Basis einer Messung von Qualität wird in einen zweiten Schritt diskutiert, welche Unterhaltungsangebote einen Public Value aufweisen und welchen dieser fehlt, so dass sie nicht zu den Aufgaben eines Service Public Senders zu zählen sind. Dabei zeigt sich, dass eine absolute Bewertung nicht gerechtfertigt ist, sondern jeweils die Kontextbedingungen eines Medienmarkts berücksichtigt werden müssen. Anhand von konkreten Unterhaltungsangeboten von europäischen Service Public Anbietern wird die Messung von Qualität illustriert und mit den Kontextbedingungen in Bezug gesetzt
Investigation of the pressure gradient of embolic protection devices
To avoid debris coming to the cerebral vessels during carotid artery stenting, embolic protection devices (EPD) are placed in front of the lesion. To evaluate their influence on the antegrade blood flow a test setup with a silicone tube simulating the internal carotid artery is realized. The pressure gradient of five different EPD was measured while particles were brought into the circuit and were caught by the systems. Additionally the microscopic structure of the systems was observed to correlate the morphology and the pressure gradient. The FiberNet device had the lowest pressure gradient. It was the only system that consists of fibers contrary to the systems RX Accunet, Angioguard RX, FilterWireEZ and EmboshieldNAV that contain porous membranes
C-Jun drives melanoma progression in PTEN wild type melanoma cells
Due to the critical impact of active AP-1 transcription factors in melanoma, it is important to define their target genes and to identify and ultimately inhibit oncogenic signals. Here we mapped the genome-wide occupancy of the AP-1 family member c-Jun in different melanoma cells and correlated AP-1 binding with transcriptome data to detect genes in melanoma regulated by c-Jun. Our analysis shows that c-Jun supports the malignant phenotype by deregulating genes in cancer-relevant signaling pathways, such as mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-kinase (PI3K) pathways. Moreover, we demonstrate that the importance of c-Jun depends on melanoma stage and mutation status of the tumor suppressor PTEN. Our study reveals that activation of c-Jun overrules the tumor suppressive effect of PTEN in early melanoma development. These findings help to understand the relevance of c-Jun within cancer pathways in different melanoma cell types, especially in relation to MAPK and PI3K pathways, which are commonly deregulated in melanomas. Consequently, targeting c-Jun in PTEN+ melanoma cells may represent a promising therapeutic strategy to inhibit survival of melanoma cells to prevent the development of a metastatic phenotype
Analysis of ADAM9 regulation and function in vestibular schwannoma primary cells
Objective
Recently, we described a disintegrin and metalloproteinase 9 (ADAM9) overexpression by Schwann cells of vestibular schwannoma (VS) and suggested that it might be a marker for VS tumor growth and invasiveness. This research note provides additional data utilizing a small cohort of VS primary cultures and tissue samples. We examined whether reconstitution of Merlin expression in VS cells regulates ADAM9 protein expression and performed lentiviral ADAM9 knock down to investigate possible effects on VS cells numbers. Moreover, the co-localization of ADAM9 and Integrins α6 and α2β1, respectively, was examined by immunofluorescence double staining.
Results
ADAM9 expression was not regulated by Merlin in VS. However, ADAM9 knock down led to 58% reduction in cell numbers in VS primary cell cultures (p < 0.0001). While ADAM9 and Integrin α2β1 were co-localized in only 22% (2 of 9) of VS, ADAM9 and Integrin α6 were co-localized in 91% (10 of 11) of VS. Therefore, we provide first observations on possible regulatory functions of ADAM9 expression in VS
Knockdown of Lamin B1 and the Corresponding Lamin B Receptor Leads to Changes in Heterochromatin State and Senescence Induction in Malignant Melanoma
Modifications in nuclear structures of cells are implicated in several diseases including cancer. They result in changes in nuclear activity, structural dynamics and cell signalling. However, the role of the nuclear lamina and related proteins in malignant melanoma is still unknown. Its molecular characterisation might lead to a deeper understanding and the development of new therapy approaches. In this study, we analysed the functional effects of dysregulated nuclear lamin B1 (LMNB1) and its nuclear receptor (LBR). According to their cellular localisation and function, we revealed that these genes are crucially involved in nuclear processes like chromatin organisation. RNA sequencing and differential gene expression analysis after knockdown of LMNB1 and LBR revealed their implication in important cellular processes driving ER stress leading to senescence and changes in chromatin state, which were also experimentally validated. We determined that melanoma cells need both molecules independently to prevent senescence. Hence, downregulation of both molecules in a BRAFV600E melanocytic senescence model as well as in etoposide-treated melanoma cells indicates both as potential senescence markers in melanoma. Our findings suggest that LMNB1 and LBR influence senescence and affect nuclear processes like chromatin condensation and thus are functionally relevant for melanoma progression