Refine
Document Type
- Article (4)
- Monograph/Edited Volume (2)
- Postprint (1)
Is part of the Bibliography
- yes (7)
Keywords
- Staphylococcus aureus (2)
- clonal complex (2)
- coagulation (2)
- epidemiology (2)
- habitat (2)
- host adaptation (2)
- immune evasion cluster (2)
- laboratory (2)
- livestock (2)
- rat (2)
Die vorliegende Publikation fällt ein wenig aus dem Rahmen der Reihe „Sorben (Wenden) - Eine Brandenburger Minderheit und ihre Thematisierung im Unterricht“. Im Gegensatz zu den anderen Teilen widmet sie sich nur einem Gegenstand - dem Stoff der Krabat-Sagen. Damit richtet sie sich hauptsächlich an Lehrkräfte im Fach Deutsch, wobei auch fachübergreifende und Fächer verbindende Aspekte berücksichtigt werden. Die Krabat-Sage zählt vor allem in der Bearbeitung von Preußler zu den bekanntesten sorbischen Stoffen. Diese sorbischen Wurzeln werden allerdings nur selten thematisiert. Daher sind viele der vorliegenden Betrachtungen zu ausgewählten Aspekten auch als Anregungen zu verstehen, unter welchen Gesichtspunkten Krabat behandelt oder gar neu interpretiert und weiterentwickelt werden könnte. Diese Handreichung ist so konzipiert, dass sie je nach Interesse ausschnittweise gelesen werden kann: Auf einen Überblick über verschiedene Krabat-Bearbeitungen folgen Betrachtungen sorbischer Aspekte als auch Möglichkeiten einer Thematisierung über den Deutsch-Unterricht hinaus. Dabei wird auf Möglichkeiten einer Exkursion in die historische Krabat-Region in der Lausitz eingegangen. Es folgen Texte zu ausgewählten Einzelaspekten. Zudem enthält diese Publikation eine Zusammenstellung von verschiedenen Krabat-Materialien und Hinweise auf Unterrichtsprojekte zur Anregung, weiteren Vertiefung bzw. für den eigenen Unterrichtseinsatz.
CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation.
The honeybee hypopharyngeal gland consists in numerous units, each comprising a secretory cell and a canal cell. The secretory cell discharges its products into a convoluted tubular membrane system, the canaliculus, which is surrounded at regular intervals by rings of actin filaments. Using probes for various membrane components, we analyze the organization of the secretory cells relative to the apicobasal configuration of epithelial cells. The canaliculus was defined by labeling with an antibody against phosphorylated ezrin/radixin/moesin (pERM), a marker protein for the apical membrane domain of epithelial cells. Anti-phosphotyrosine visualizes the canalicular system, possibly by staining the microvillar tips. The open end of the canaliculus leads to a region in which the secretory cell is attached to the canal cell by adherens and septate junctions. The remaining plasma membrane stains for Na,K-ATPase and spectrin and represents the basolateral domain. We also used fluorophore-tagged phalloidin, anti-phosphotyrosine and anti-pERM as probes for the canaliculus in order to describe fine-structural changes in the organization of the canalicular system during the adult life cycle. These probes in conjunction with fluorescence microscopy allow the fast and detailed three-dimensional analysis of the canalicular membrane system and its structural changes in a developmental mode or in response to environmental factors.
Fullerene-based acceptors have dominated organic solar cells for almost two decades. It is only within the last few years that alternative acceptors rival their dominance, introducing much more flexibility in the optoelectronic properties of these material blends. However, a fundamental physical understanding of the processes that drive charge separation at organic heterojunctions is still missing, but urgently needed to direct further material improvements. Here a combined experimental and theoretical approach is used to understand the intimate mechanisms by which molecular structure contributes to exciton dissociation, charge separation, and charge recombination at the donor-acceptor (D-A) interface. Model systems comprised of polythiophene-based donor and rylene diimide-based acceptor polymers are used and a detailed density functional theory (DFT) investigation is performed. The results point to the roles that geometric deformations and direct-contact intermolecular polarization play in establishing a driving force ( energy gradient) for the optoelectronic processes taking place at the interface. A substantial impact for this driving force is found to stem from polymer deformations at the interface, a finding that can clearly lead to new design approaches in the development of the next generation of conjugated polymers and small molecules.
Rats are a reservoir of human- and livestock-associated methicillin-resistant Staphylococcus aureus (MRSA). However, the composition of the natural S. aureus population in wild and laboratory rats is largely unknown. Here, 144 nasal S. aureus isolates from free-living wild rats, captive wild rats and laboratory rats were genotyped and profiled for antibiotic resistances and human-specific virulence genes. The nasal S. aureus carriage rate was higher among wild rats (23.4%) than laboratory rats (12.3%). Free-living wild rats were primarily colonized with isolates of clonal complex (CC) 49 and CC130 and maintained these strains even in husbandry. Moreover, upon livestock contact, CC398 isolates were acquired. In contrast, laboratory rats were colonized with many different S. aureus lineages—many of which are commonly found in humans. Five captive wild rats were colonized with CC398-MRSA. Moreover, a single CC30-MRSA and two CC130-MRSA were detected in free-living or captive wild rats. Rat-derived S. aureus isolates rarely harbored the phage-carried immune evasion gene cluster or superantigen genes, suggesting long-term adaptation to their host. Taken together, our study revealed a natural S. aureus population in wild rats, as well as a colonization pressure on wild and laboratory rats by exposure to livestock- and human-associated S. aureus, respectively.
Rats are a reservoir of human- and livestock-associated methicillin-resistant Staphylococcus aureus (MRSA). However, the composition of the natural S. aureus population in wild and laboratory rats is largely unknown. Here, 144 nasal S. aureus isolates from free-living wild rats, captive wild rats and laboratory rats were genotyped and profiled for antibiotic resistances and human-specific virulence genes. The nasal S. aureus carriage rate was higher among wild rats (23.4%) than laboratory rats (12.3%). Free-living wild rats were primarily colonized with isolates of clonal complex (CC) 49 and CC130 and maintained these strains even in husbandry. Moreover, upon livestock contact, CC398 isolates were acquired. In contrast, laboratory rats were colonized with many different S. aureus lineages—many of which are commonly found in humans. Five captive wild rats were colonized with CC398-MRSA. Moreover, a single CC30-MRSA and two CC130-MRSA were detected in free-living or captive wild rats. Rat-derived S. aureus isolates rarely harbored the phage-carried immune evasion gene cluster or superantigen genes, suggesting long-term adaptation to their host. Taken together, our study revealed a natural S. aureus population in wild rats, as well as a colonization pressure on wild and laboratory rats by exposure to livestock- and human-associated S. aureus, respectively.
Software-Fehlerinjektion
(2016)
Fehlerinjektion ist ein essentielles Werkzeug, um die Fehlertoleranz komplexer Softwaresysteme experimentell zu evaluieren.
Wir berichten über das Seminar zum Thema Software-Fehlerinjektion, das am Fachgebiet für Betriebssysteme und Middleware am Hasso-Plattner-Institut der Universität Potsdam im Sommersemester 2015 stattfand.
In dem Seminar ging es darum, verschiedene Fehlerinjektionsansätze und -werkzeuge anzuwenden und hinsichtlich ihrer Anwendbarkeit in verschiedenen Szenarien zu bewerten.
In diesem Bericht werden die studierten Ansätze vorgestellt und verglichen.