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- ItemRaf kinases mediate the phosphorylation of eukaryotic translation elongation factor 1A and regulate its stability in eukaryotic cells(London : Nature Publishing Group, 2012) Sanges, C.; Scheuermann, C.; Zahedi, R.P.; Sickmann, A.; Lamberti, A.; Migliaccio, N.; Baljuls, A.; Marra, M.; Zappavigna, S.; Reinders, J.; Rapp, U.; Abbruzzese, A.; Caraglia, M.; Arcari, P.We identified eukaryotic translation elongation factor 1A (eEF1A) Raf-mediated phosphorylation sites and defined their role in the regulation of eEF1A half-life and of apoptosis of human cancer cells. Mass spectrometry identified in vitro S21 and T88 as phosphorylation sites mediated by B-Raf but not C-Raf on eEF1A1 whereas S21 was phosphorylated on eEF1A2 by both B- and C-Raf. Interestingly, S21 belongs to the first eEF1A GTP/GDP-binding consensus sequence. Phosphorylation of S21 was strongly enhanced when both eEF1A isoforms were preincubated prior the assay with C-Raf, suggesting that the eEF1A isoforms can heterodimerize thus increasing the accessibility of S21 to the phosphate. Overexpression of eEF1A1 in COS 7 cells confirmed the phosphorylation of T88 also in vivo. Compared with wt, in COS 7 cells overexpressed phosphodeficient (A) and phospho-mimicking (D) mutants of eEF1A1 (S21A/D and T88A/D) and of eEF1A2 (S21A/D), resulted less stable and more rapidly proteasome degraded. Transfection of S21 A/D eEF1A mutants in H1355 cells increased apoptosis in comparison with the wt isoforms. It indicates that the blockage of S21 interferes with or even supports C-Raf induced apoptosis rather than cell survival. Raf-mediated regulation of this site could be a crucial mechanism involved in the functional switching of eEF1A between its role in protein biosynthesis and its participation in other cellular processes.
- ItemProdukthaftung in der Apotheke(Stuttgart : Deutscher Apotheker Verlag, 2005) Diebold, Steffen M.Stellt ein Apotheker Arzneimittel, Medizinprodukte oder andere apothekenübliche Waren (z.B. Kosmetika oder Mixturen nach Angaben von Heilpraktikern, Homöopathen oder Anthroposophen) in seiner Offizin selbst her, so haftet er (grundsätzlich) einem dadurch ggf. geschädigten Kunden (auch) nach den Vorschriften des Produkthaftungsgesetzes. Diese Haftung besteht unabhängig vom eigenen Verschulden. Sie greift auch bei der Einfuhr von Arzneimitteln aus Staaten, die nicht zum Europäischen Wirtschaftsraum gehören, sowie bei Import und Abgabe von aus Drittländern eingeführten und im Geltungsbereich des Arzneimittelgesetzes (AMG) nicht zugelassenen Fertigarzneimitteln nach § 73 (3) AMG.
- ItemOxaliplatin-DNA adduct formation in white blood cells of cancer patients(London : Nature Publishing Group, 2008) Pieck, A.C.; Drescher, A.; Wiesmann, K.G.; Messerschmidt, J.; Weber, G.; Strumberg, D.; Hilger, R.A.; Scheulen, M.E.; Jaehde, U.In this study, we investigated the kinetics of oxaliplatin-DNA adduct formation in white blood cells of cancer patients in relation to efficacy as well as oxaliplatin-associated neurotoxicity. Thirty-seven patients with various solid tumours received 130 mg m−2 oxaliplatin as a 2-h infusion. Oxaliplatin-DNA adduct levels were measured in the first cycle using adsorptive stripping voltammetry. Platinum concentrations were measured in ultrafiltrate and plasma using a validated flameless atomic absorption spectrometry method. DNA adduct levels showed a characteristic time course, but were not correlated to platinum pharmacokinetics and varied considerably among individuals. In patients showing tumour response, adduct levels after 24 and 48 h were significantly higher than in nonresponders. Oxaliplatin-induced neurotoxicity was more pronounced but was not significantly different in patients with high adduct levels. The potential of oxaliplatin-DNA adduct measurements as pharmacodynamic end point should be further investigated in future trials.
- ItemWerbung für den Apothekenbetrieb in örtlichen Festschriften(Stuttgart : Deutscher Apotheker Verlag, 2004-09) Diebold, Steffen M.Der vorliegende Beitrag widmet sich einem Aspekt der Sozial- und Kulturgeschichte, der bislang weder von der volkskundlichen noch von der sozialwissenschaftlichen Forschung aufgegriffen worden ist. Am Beispiel von Vereinsfestschriften des 20. Jahrhunderts wird demonstriert, wie sich Apotheken außerhalb von Fachkreisen der Öffentlichkeit präsentierten und dadurch für ihr Unternehmen warben. Über den alltagshistorischen Aspekt hinaus vermitteln die Annoncen der Festschriften en passant damit auch einen Einblick in wirtschaftliche, gesellschaftliche oder soziale Verhältnisse im Deutschland der Nachkriegszeit.
- ItemGain of a 500-fold sensitivity on an intravital MR Contrast Agent based on an endohedral Gadolinium-Cluster-Fullerene-Conjugate: A new chance in cancer diagnostics(Sydney : Ivyspring, 2010) Braun, Klaus; Dunsch, Lothar; Pipkorn, Ruediger; Bock, Michael; Baeuerle, Tobias; Yang, Shangfeng; Waldeck, Waldemar; Wiessler, ManfredAmong the applications of fullerene technology in health sciences the expanding field of magnetic resonance imaging (MRI) of molecular processes is most challenging. Here we present the synthesis and application of a GdxSc3-xN@C80-BioShuttle-conjugate referred to as Gd-cluster@-BioShuttle, which features high proton relaxation and, in comparison to the commonly used contrast agents, high signal enhancement at very low Gd concentrations. This modularly designed contrast agent represents a new tool for improved monitoring and evaluation of interventions at the gene transcription level. Also, a widespread monitoring to track individual cells is possible, as well as sensing of microenvironments. Furthermore, BioShuttle can also deliver constructs for transfection or active pharmaceutical ingredients, and scaffolding for incorporation with the host's body. Using the Gd-cluster@-BioShuttle as MRI contrast agent allows an improved evaluation of radio- or chemotherapy treated tissues.
- ItemDipA, a pore-forming protein in the outer membrane of lyme disease spirochetes exhibits specificity for the permeation of dicarboxylate(San Francisco, CA : Public Library of Science, 2012) Thein, Marcus; Bonde, Mari; Bunikis, Ignas; Denker, Katrin; Sickmann, Albert; Bergström, Sven; Benz, RolandLyme disease Borreliae are highly dependent on the uptake of nutrients provided by their hosts. Our study describes the identification of a 36 kDa protein that functions as putative dicarboxylate-specific porin in the outer membrane of Lyme disease Borrelia. The protein was purified by hydroxyapatite chromatography from Borrelia burgdorferi B31 and designated as DipA, for dicarboxylate-specific porin A. DipA was partially sequenced, and corresponding genes were identified in the genomes of B. burgdorferi B31, Borrelia garinii PBi and Borrelia afzelii PKo. DipA exhibits high homology to the Oms38 porins of relapsing fever Borreliae. B. burgdorferi DipA was characterized using the black lipid bilayer assay. The protein has a singlechannel conductance of 50 pS in 1 M KCl, is slightly selective for anions with a permeability ratio for cations over anions of 0.57 in KCl and is not voltage-dependent. The channel could be partly blocked by different di- and tricarboxylic anions. Particular high stability constants up to about 28,000 l/mol (in 0.1 M KCl) were obtained among the 11 tested anions for oxaloacetate, 2-oxoglutarate and citrate. The results imply that DipA forms a porin specific for dicarboxylates which may play an important role for the uptake of specific nutrients in different Borrelia species.
- ItemIn vitro model of metastasis to bone marrow mediates prostate cancer castration resistant growth through paracrine and extracellular matrix factors(San Francisco, CA : Public Library of Science, 2012) Lescarbeau, R.M.; Seib, F.P.; Prewitz, M.; Werner, C.; Kaplan, D.L.The spread of prostate cancer cells to the bone marrow microenvironment and castration resistant growth are key steps in disease progression and significant sources of morbidity. However, the biological significance of mesenchymal stem cells (MSCs) and bone marrow derived extracellular matrix (BM-ECM) in this process is not fully understood. We therefore established an in vitro engineered bone marrow tissue model that incorporates hMSCs and BM-ECM to facilitate mechanistic studies of prostate cancer cell survival in androgen-depleted media in response to paracrine factors and BM-ECM. hMSC-derived paracrine factors increased LNCaP cell survival, which was in part attributed to IGFR and IL6 signaling. In addition, BM-ECM increased LNCaP and MDA-PCa-2b cell survival in androgen-depleted conditions, and induced chemoresistance and morphological changes in LNCaPs. To determine the effect of BM-ECM on cell signaling, the phosphorylation status of 46 kinases was examined. Increases in the phosphorylation of MAPK pathway-related proteins as well as sustained Akt phosphorylation were observed in BM-ECM cultures when compared to cultures grown on plasma-treated polystyrene. Blocking MEK1/2 or the PI3K pathway led to a significant reduction in LNCaP survival when cultured on BM-ECM in androgen-depleted conditions. The clinical relevance of these observations was determined by analyzing Erk phosphorylation in human bone metastatic prostate cancer versus non-metastatic prostate cancer, and increased phosphorylation was seen in the metastatic samples. Here we describe an engineered bone marrow model that mimics many features observed in patients and provides a platform for mechanistic in vitro studies.
- ItemVolatile organic compounds in uremia(San Francisco, CA : Public Library of Science, 2012) Pagonas, Nikolaos; Vautz, Wolfgang; Seifert, Luzia; Slodzinski, Rafael; Jankowski, Joachim; Zidek, Walter; Westhoff, Timm H.Background: Although ‘‘uremic fetor’’ has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia. Methods: Breath analysis was performed in 28 adults with an eGFR $60 ml/min per 1.73 m2, 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m2, and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry. Results: Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p,0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis. Conclusion: Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules.
- ItemIdentification of Eps15 as antigen recognized by the monoclonal antibodies aa2 and ab52 of the wuerzburg hybridoma library against Drosophila brain(San Francisco, CA : Public Library of Science, 2011) Halder, Partho; Chen, Yi-chun; Brauckhoff, Janine; Hofbauer, Alois; Dabauvalle, Marie-Christine; Lewandrowski, Urs; Winkler, Christiane; Sickmann, Albert; Buchner, ErichThe Wuerzburg Hybridoma Library against the Drosophila brain represents a collection of around 200 monoclonal antibodies that bind to specific structures in the Drosophila brain. Here we describe the immunohistochemical staining patterns, the Western blot signals of one- and two-dimensional electrophoretic separation, and the mass spectrometric characterization of the target protein candidates recognized by the monoclonal antibodies aa2 and ab52 from the library. Analysis of a mutant of a candidate gene identified the Drosophila homolog of the Epidermal growth factor receptor Pathway Substrate clone 15 (Eps15) as the antigen for these two antibodies.
- ItemAlterations in Event Related Potentials (ERP) associated with tinnitus distress and attention(Dordrecht [u.a.] : Springer Science + Business Media B.V, 2008) Delb, W.; Strauss, D.J.; Low, Y.F.; Seidler, H.; Rheinschmitt, A.; Wobrock, T.; D'Amelio, R.Tinnitus related distress corresponds to different degrees of attention paid to the tinnitus. Shifting attention to a signal other than the tinnitus is therefore particularly difficult for patients with high tinnitus related distress. As attention effects on Event Related Potentials (ERP) have been shown this should be reflected in ERP measurements (N100, phase locking). In order to prove this hypothesis single sweep ERP recordings were obtained in 41 tinnitus patients as well as 10 control subjects during a period of time when attention was shifted to a tone (attended) and during a second phase (unattended) when they did not focus attention to the tone. Whereas tinnitus patients with low distress showed a significant reduction in both N100 amplitude and phase locking when comparing the attended and unattended measurement condition a group of patients with high tinnitus related distress did not show such ERP alterations. Using single sweep ERP measurements the results of our study show, that attention in high tinnitus related distress patients is captured by their tinnitus significantly more than in low distress patients. Furthermore our results provide the basis for future neurofeedback based tinnitus therapies aiming at maximizing the ability to shift attention away from the tinnitus. © 2008 The Author(s).