@article{RantamaekiVesaAntilaetal.2011, author = {Rantam{\"a}ki, Tomi and Vesa, Liisa and Antila, Hanna and Di Lieto, Antonio and Tammela, P{\"a}ivi and Schmitt, Angelika and Lesch, Klaus-Peter and Rios, Maribel and Castr{\´e}n, Eero}, title = {Antidepressant Drugs Transactivate TrkB Neurotrophin Receptors in the Adult Rodent Brain Independently of BDNF and Monoamine Transporter Blockade}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0020567}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133746}, pages = {e20567}, year = {2011}, abstract = {Background: Antidepressant drugs (ADs) have been shown to activate BDNF (brain-derived neurotrophic factor) receptor TrkB in the rodent brain but the mechanism underlying this phenomenon remains unclear. ADs act as monoamine reuptake inhibitors and after prolonged treatments regulate brain bdnf mRNA levels indicating that monoamine-BDNF signaling regulate AD-induced TrkB activation in vivo. However, recent findings demonstrate that Trk receptors can be transactivated independently of their neurotrophin ligands. Methodology: In this study we examined the role of BDNF, TrkB kinase activity and monoamine reuptake in the AD-induced TrkB activation in vivo and in vitro by employing several transgenic mouse models, cultured neurons and TrkB-expressing cell lines. Principal Findings: Using a chemical-genetic TrkB(F616A) mutant and TrkB overexpressing mice, we demonstrate that ADs specifically activate both the maturely and immaturely glycosylated forms of TrkB receptors in the brain in a TrkB kinase dependent manner. However, the tricyclic AD imipramine readily induced the phosphorylation of TrkB receptors in conditional bdnf(-/-) knock-out mice (132.4+/-8.5\% of control; P = 0.01), indicating that BDNF is not required for the TrkB activation. Moreover, using serotonin transporter (SERT) deficient mice and chemical lesions of monoaminergic neurons we show that neither a functional SERT nor monoamines are required for the TrkB phosphorylation response induced by the serotonin selective reuptake inhibitors fluoxetine or citalopram, or norepinephrine selective reuptake inhibitor reboxetine. However, neither ADs nor monoamine transmitters activated TrkB in cultured neurons or cell lines expressing TrkB receptors, arguing that ADs do not directly bind to TrkB. Conclusions: The present findings suggest that ADs transactivate brain TrkB receptors independently of BDNF and monoamine reuptake blockade and emphasize the need of an intact tissue context for the ability of ADs to induce TrkB activity in brain.}, language = {en} } @article{SongXiuHuangetal.2011, author = {Song, Ning-Ning and Xiu, Jian-Bo and Huang, Ying and Chen, Jia-Yin and Zhang, Lei and Gutknecht, Lise and Lesch, Klaus Peter and Li, He and Ding, Yu-Qiang}, title = {Adult Raphe-Specific Deletion of Lmx1b Leads to Central Serotonin Deficiency}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {1}, doi = {10.1371/journal.pone.0015998}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133581}, pages = {e15998}, year = {2011}, abstract = {The transcription factor Lmx1b is essential for the differentiation and survival of central serotonergic (5-HTergic) neurons during embryonic development. However, the role of Lmx1b in adult 5-HTergic neurons is unknown. We used an inducible Cre-LoxP system to selectively inactivate Lmx1b expression in the raphe nuclei of adult mice. Pet1-CreER(T2) mice were generated and crossed with Lmx1b(flox/flox) mice to obtain Pet1-CreER(T2); Lmx1b(flox/flox) mice (which termed as Lmx1b iCKO). After administration of tamoxifen, the level of 5-HT in the brain of Lmx1b iCKO mice was reduced to 60\% of that in control mice, and the expression of tryptophan hydroxylase 2 (Tph2), serotonin transporter (Sert) and vesicular monoamine transporter 2 (Vmat2) was greatly down-regulated. On the other hand, the expression of dopamine and norepinephrine as well as aromatic L-amino acid decarboxylase (Aadc) and Pet1 was unchanged. Our results reveal that Lmx1b is required for the biosynthesis of 5-HT in adult mouse brain, and it may be involved in maintaining normal functions of central 5-HTergic neurons by regulating the expression of Tph2, Sert and Vmat2.}, language = {en} } @article{FischerMaierSiegemundetal.2011, author = {Fischer, Roman and Maier, Olaf and Siegemund, Martin and Wajant, Harald and Scheurich, Peter and Pfizenmaier, Klaus}, title = {A TNF Receptor 2 Selective Agonist Rescues Human Neurons from Oxidative Stress-Induced Cell Death}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {11}, doi = {10.1371/journal.pone.0027621}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133552}, pages = {e27621}, year = {2011}, abstract = {Tumor necrosis factor (TNF) plays a dual role in neurodegenerative diseases. Whereas TNF receptor (TNFR) 1 is predominantly associated with neurodegeneration, TNFR2 is involved in tissue regeneration and neuroprotection. Accordingly, the availability of TNFR2-selective agonists could allow the development of new therapeutic treatments of neurodegenerative diseases. We constructed a soluble, human TNFR2 agonist (TNC-scTNF(R2)) by genetic fusion of the trimerization domain of tenascin C to a TNFR2-selective single-chain TNF molecule, which is comprised of three TNF domains connected by short peptide linkers. TNC-scTNFR2 specifically activated TNFR2 and possessed membrane-TNF mimetic activity, resulting in TNFR2 signaling complex formation and activation of downstream signaling pathways. Protection from neurodegeneration was assessed using the human dopaminergic neuronal cell line LUHMES. First we show that TNC-scTNF(R2) interfered with cell death pathways subsequent to H(2)O(2) exposure. Protection from cell death was dependent on TNFR2 activation of the PI3K-PKB/Akt pathway, evident from restoration of H(2)O(2) sensitivity in the presence of PI3K inhibitor LY294002. Second, in an in vitro model of Parkinson disease, TNC-scTNFR(2) rescues neurons after induction of cell death by 6-OHDA. Since TNFR2 is not only promoting anti-apoptotic responses but also plays an important role in tissue regeneration, activation of TNFR2 signaling by TNC-scTNF(R2) appears a promising strategy to ameliorate neurodegenerative processes.}, language = {en} } @article{EckhardtAndersMuranyietal.2011, author = {Eckhardt, Manon and Anders, Maria and Muranyi, Walter and Heilemann, Mike and Krijnse-Locker, Jacomine and M{\"u}ller, Barbara}, title = {A SNAP-Tagged Derivative of HIV-1-A Versatile Tool to Study Virus-Cell Interactions}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {7}, doi = {10.1371/journal.pone.0022007}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133534}, pages = {e22007}, year = {2011}, abstract = {Fluorescently labeled human immunodeficiency virus (HIV) derivatives, combined with the use of advanced fluorescence microscopy techniques, allow the direct visualization of dynamic events and individual steps in the viral life cycle. HIV proteins tagged with fluorescent proteins (FPs) have been successfully used for live-cell imaging analyses of HIV-cell interactions. However, FPs display limitations with respect to their physicochemical properties, and their maturation kinetics. Furthermore, several independent FP-tagged constructs have to be cloned and characterized in order to obtain spectral variations suitable for multi-color imaging setups. In contrast, the so-called SNAP-tag represents a genetically encoded non-fluorescent tag which mediates specific covalent coupling to fluorescent substrate molecules in a self-labeling reaction. Fusion of the SNAP-tag to the protein of interest allows specific labeling of the fusion protein with a variety of synthetic dyes, thereby offering enhanced flexibility for fluorescence imaging approaches. Here we describe the construction and characterization of the HIV derivative HIV(SNAP), which carries the SNAP-tag as an additional domain within the viral structural polyprotein Gag. Introduction of the tag close to the C-terminus of the matrix domain of Gag did not interfere with particle assembly, release or proteolytic virus maturation. The modified virions were infectious and could be propagated in tissue culture, albeit with reduced replication capacity. Insertion of the SNAP domain within Gag allowed specific staining of the viral polyprotein in the context of virus producing cells using a SNAP reactive dye as well as the visualization of individual virions and viral budding sites by stochastic optical reconstruction microscopy. Thus, HIV(SNAP) represents a versatile tool which expands the possibilities for the analysis of HIV-cell interactions using live cell imaging and sub-diffraction fluorescence microscopy.}, language = {en} } @article{KistlerSiwyFranketal.2011, author = {Kistler, Andreas D. and Siwy, Justyna and Frank, Breunig and Jeevaratnam, Praveen and Scherl, Alexander and Mullen, William and Warnock, David G. and Wanner, Christoph and Hughes, Derralynn A. and Mischak, Harald and W{\"u}thrich, Rudolf P. and Serra, Andreas L.}, title = {A Distinct Urinary Biomarker Pattern Characteristic of Female Fabry Patients That Mirrors Response to Enzyme Replacement Therapy}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0020534}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133526}, pages = {e20534}, year = {2011}, abstract = {Female patients affected by Fabry disease, an X-linked lysosomal storage disorder, exhibit a wide spectrum of symptoms, which renders diagnosis, and treatment decisions challenging. No diagnostic test, other than sequencing of the alpha-galactosidase A gene, is available and no biomarker has been proven useful to screen for the disease, predict disease course and monitor response to enzyme replacement therapy. Here, we used urine proteomic analysis based on capillary electrophoresis coupled to mass spectrometry and identified a biomarker profile in adult female Fabry patients. Urine samples were taken from 35 treatment-naive female Fabry patients and were compared to 89 age-matched healthy controls. We found a diagnostic biomarker pattern that exhibited 88.2\% sensitivity and 97.8\% specificity when tested in an independent validation cohort consisting of 17 treatment-naive Fabry patients and 45 controls. The model remained highly specific when applied to additional control patients with a variety of other renal, metabolic and cardiovascular diseases. Several of the 64 identified diagnostic biomarkers showed correlations with measures of disease severity. Notably, most biomarkers responded to enzyme replacement therapy, and 8 of 11 treated patients scored negative for Fabry disease in the diagnostic model. In conclusion, we defined a urinary biomarker model that seems to be of diagnostic use for Fabry disease in female patients and may be used to monitor response to enzyme replacement therapy.}, language = {en} } @article{BilalicKieselPohletal.2011, author = {Bilalic, Merim and Kiesel, Andrea and Pohl, Carsten and Erb, Michael and Grodd, Wolfgang}, title = {It Takes Two-Skilled Recognition of Objects Engages Lateral Areas in Both Hemispheres}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {1}, doi = {10.1371/journal.pone.0016202}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176935}, pages = {e16202}, year = {2011}, abstract = {Our object recognition abilities, a direct product of our experience with objects, are fine-tuned to perfection. Left temporal and lateral areas along the dorsal, action related stream, as well as left infero-temporal areas along the ventral, object related stream are engaged in object recognition. Here we show that expertise modulates the activity of dorsal areas in the recognition of man-made objects with clearly specified functions. Expert chess players were faster than chess novices in identifying chess objects and their functional relations. Experts' advantage was domain-specific as there were no differences between groups in a control task featuring geometrical shapes. The pattern of eye movements supported the notion that experts' extensive knowledge about domain objects and their functions enabled superior recognition even when experts were not directly fixating the objects of interest. Functional magnetic resonance imaging (fMRI) related exclusively the areas along the dorsal stream to chess specific object recognition. Besides the commonly involved left temporal and parietal lateral brain areas, we found that only in experts homologous areas on the right hemisphere were also engaged in chess specific object recognition. Based on these results, we discuss whether skilled object recognition does not only involve a more efficient version of the processes found in non-skilled recognition, but also qualitatively different cognitive processes which engage additional brain areas}, language = {en} } @article{MatosSucenaMachadoetal.2011, author = {Matos, Isa and Sucena, {\`E}lio and Machado, Miguel P and Gardner, Rui and In{\´a}cio, {\^A}ngela and Schartl, Manfred and Coelho, Maria M}, title = {Ploidy mosaicism and allele-specific gene expression differences in the allopolyploid \(Squalius\) \(alburnoides\)}, series = {BMC Genetics}, volume = {12}, journal = {BMC Genetics}, number = {101}, doi = {10.1186/1471-2156-12-101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142879}, pages = {1-10}, year = {2011}, abstract = {Background Squalius alburnoides is an Iberian cyprinid fish resulting from an interspecific hybridisation between Squalius pyrenaicus females (P genome) and males of an unknown Anaecypris hispanica- like species (A genome). S. alburnoides is an allopolyploid hybridogenetic complex, which makes it a likely candidate for ploidy mosaicism occurrence, and is also an interesting model to address questions about gene expression regulation and genomic interactions. Indeed, it was previously suggested that in S. alburnoides triploids (PAA composition) silencing of one of the three alleles (mainly of the P allele) occurs. However, not a whole haplome is inactivated but a more or less random inactivation of alleles varying between individuals and even between organs of the same fish was seen. In this work we intended to correlate expression differences between individuals and/or between organs to the occurrence of mosaicism, evaluating if mosaics could explain previous observations and its impact on the assessment of gene expression patterns. Results To achieve our goal, we developed flow cytometry and cell sorting protocols for this system generating more homogenous cellular and transcriptional samples. With this set-up we detected 10\% ploidy mosaicism within the S. alburnoides complex, and determined the allelic expression profiles of ubiquitously expressed genes (rpl8; gapdh and β-actin) in cells from liver and kidney of mosaic and non-mosaic individuals coming from different rivers over a wide geographic range. Conclusions Ploidy mosaicism occurs sporadically within the S. alburnoides complex, but in a frequency significantly higher than reported for other organisms. Moreover, we could exclude the influence of this phenomenon on the detection of variable allelic expression profiles of ubiquitously expressed genes (rpl8; gapdh and β-actin) in cells from liver and kidney of triploid individuals. Finally, we determined that the expression patterns previously detected only in a narrow geographic range is not a local restricted phenomenon but is pervasive in rivers where S. pyrenaicus is sympatric with S. alburnoides. We discuss mechanisms that could lead to the formation of mosaic S. alburnoides and hypothesise about a relaxation of the mechanisms that impose a tight control over mitosis and ploidy control in mixoploids."}, language = {en} } @article{HanWiedwaldBiskupeketal.2011, author = {Han, Luyang and Wiedwald, Ulf and Biskupek, Johannes and Fauth, Kai and Kaiser, Ute and Ziemann, Paul}, title = {Nanoscaled alloy formation from self-assembled elemental Co nanoparticles on top of Pt films}, series = {Beilstein Journal of Nanotechnology}, volume = {2}, journal = {Beilstein Journal of Nanotechnology}, doi = {10.3762/bjnano.2.51}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142869}, pages = {473-485}, year = {2011}, abstract = {The thermally activated formation of nanoscale CoPt alloys was investigated, after deposition of self-assembled Co nanoparticles on textured Pt(111) and epitaxial Pt(100) films on MgO(100) and SrTiO3(100) substrates, respectively. For this purpose, metallic Co nanoparticles (diameter 7 nm) were prepared with a spacing of 100 nm by deposition of precursor-loaded reverse micelles, subsequent plasma etching and reduction on flat Pt surfaces. The samples were then annealed at successively higher temperatures under a H2 atmosphere, and the resulting variations of their structure, morphology and magnetic properties were characterized. We observed pronounced differences in the diffusion and alloying of Co nanoparticles on Pt films with different orientations and microstructures. On textured Pt(111) films exhibiting grain sizes (20-30 nm) smaller than the particle spacing (100 nm), the formation of local nanoalloys at the surface is strongly suppressed and Co incorporation into the film via grain boundaries is favoured. In contrast, due to the absence of grain boundaries on high quality epitaxial Pt(100) films with micron-sized grains, local alloying at the film surface was established. Signatures of alloy formation were evident from magnetic investigations. Upon annealing to temperatures up to 380 °C, we found an increase both of the coercive field and of the Co orbital magnetic moment, indicating the formation of a CoPt phase with strongly increased magnetic anisotropy compared to pure Co. At higher temperatures, however, the Co atoms diffuse into a nearby surface region where Pt-rich compounds are formed, as shown by element-specific microscopy.}, language = {en} } @article{TonyBurmesterSchulzeKoopsetal.2011, author = {Tony, Hans-Peter and Burmester, Gerd and Schulze-Koops, Hendrik and Grunke, Mathias and Henes, Joerg and K{\"o}tter, Ina and Haas, Judith and Unger, Leonore and Lovric, Svjetlana and Haubitz, Marion and Fischer-Betz, Rebecca and Chehab, Gamal and Rubbert-Roth, Andrea and Specker, Christof and Weinerth, Jutta and Holle, Julia and M{\"u}ller-Ladner, Ulf and K{\"o}nig, Ramona and Fiehn, Christoph and Burgwinkel, Philip and Budde, Klemens and S{\"o}rensen, Helmut and Meurer, Michael and Aringer, Martin and Kieseier, Bernd and Erfurt-Berge, Cornelia and Sticherling, Michael and Veelken, Roland and Ziemann, Ulf and Strutz, Frank and von Wussow, Praxis and Meier, Florian MP and Hunzelmann, Nico and Schmidt, Enno and Bergner, Raoul and Schwarting, Andreas and Eming, R{\"u}diger and Schwarz-Eywill, Michael and Wassenberg, Siegfried and Fleck, Martin and Metzler, Claudia and Zettl, Uwe and Westphal, Jens and Heitmann, Stefan and Herzog, Anna L. and Wiendl, Heinz and Jakob, Waltraud and Schmidt, Elvira and Freivogel, Klaus and D{\"o}rner, Thomas and Hertl, Michael and Stadler, Rudolf}, title = {Safety and clinical outcomes of rituximab therapy in patients with different autoimmune diseases: experience from a national registry (GRAID)}, series = {Arthritis Research \& Therapy}, volume = {13}, journal = {Arthritis Research \& Therapy}, number = {R75}, doi = {10.1186/ar3337}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142856}, pages = {1-14}, year = {2011}, abstract = {Introduction: Evidence from a number of open-label, uncontrolled studies has suggested that rituximab may benefit patients with autoimmune diseases who are refractory to standard-of-care. The objective of this study was to evaluate the safety and clinical outcomes of rituximab in several standard-of-care-refractory autoimmune diseases (within rheumatology, nephrology, dermatology and neurology) other than rheumatoid arthritis or non-Hodgkin's lymphoma in a real-life clinical setting. Methods: Patients who received rituximab having shown an inadequate response to standard-of-care had their safety and clinical outcomes data retrospectively analysed as part of the German Registry of Autoimmune Diseases. The main outcome measures were safety and clinical response, as judged at the discretion of the investigators. Results: A total of 370 patients (299 patient-years) with various autoimmune diseases (23.0\% with systemic lupus erythematosus, 15.7\% antineutrophil cytoplasmic antibody-associated granulomatous vasculitides, 15.1\% multiple sclerosis and 10.0\% pemphigus) from 42 centres received a mean dose of 2,440 mg of rituximab over a median (range) of 194 (180 to 1,407) days. The overall rate of serious infections was 5.3 per 100 patient-years during rituximab therapy. Opportunistic infections were infrequent across the whole study population, and mostly occurred in patients with systemic lupus erythematosus. There were 11 deaths (3.0\% of patients) after rituximab treatment (mean 11.6 months after first infusion, range 0.8 to 31.3 months), with most of the deaths caused by infections. Overall (n = 293), 13.3\% of patients showed no response, 45.1\% showed a partial response and 41.6\% showed a complete response. Responses were also reflected by reduced use of glucocorticoids and various immunosuppressives during rituximab therapy and follow-up compared with before rituximab. Rituximab generally had a positive effect on patient well-being (physician's visual analogue scale; mean improvement from baseline of 12.1 mm)}, language = {en} } @article{HertleinSturmKircheretal.2011, author = {Hertlein, Tobias and Sturm, Volker and Kircher, Stefan and Basse-L{\"u}sebrink, Thomas and Haddad, Daniel and Ohlsen, Knut and Jakob, Peter}, title = {Visualization of Abscess Formation in a Murine Thigh Infection Model of \(Staphylococcus\) \(aureus\) by (19)F-Magnetic Resonance Imaging (MRI)}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {3}, doi = {10.1371/journal.pone.0018246}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142846}, pages = {e18246}, year = {2011}, abstract = {Background: During the last years, (19)F-MRI and perfluorocarbon nanoemulsion (PFC) emerged as a powerful contrast agent methodology to track cells and to visualize inflammation. We applied this new modality to visualize deep tissue abscesses during acute and chronic phase of inflammation caused by Staphylococcus aureus infection. Methodology and Principal Findings: In this study, a murine thigh infection model was used to induce abscess formation and PFC or CLIO (cross linked ironoxides) was administered during acute or chronic phase of inflammation. 24 h after inoculation, the contrast agent accumulation was imaged at the site of infection by MRI. Measurements revealed a strong accumulation of PFC at the abscess rim at acute and chronic phase of infection. The pattern was similar to CLIO accumulation at chronic phase and formed a hollow sphere around the edema area. Histology revealed strong influx of neutrophils at the site of infection and to a smaller extend macrophages during acute phase and strong influx of macrophages at chronic phase of inflammation. Conclusion and Significance: We introduce (19)F-MRI in combination with PFC nanoemulsions as a new platform to visualize abscess formation in a murine thigh infection model of S. aureus. The possibility to track immune cells in vivo by this modality offers new opportunities to investigate host immune response, the efficacy of antibacterial therapies and the influence of virulence factors for pathogenesis.}, language = {en} }