@article{SinnEichlerMuelleretal.2011, author = {Sinn, Stefan and Eichler, Mirjam and M{\"u}ller, Lothar and B{\"u}nger, Daniel and Groll, J{\"u}ergen and Ziemer, Gerhard and Rupp, Frank and Northoff, Hinnak and Geis-Gerstorfer, J{\"u}rgen and Gehring, Frank K. and Wendel, Hans P.}, title = {NCO-sP(EO-stat-PO) Coatings on Gold Sensors-a QCM Study of Hemocompatibility}, series = {Sensors}, volume = {11}, journal = {Sensors}, number = {5}, doi = {10.3390/s110505253}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141110}, pages = {5253-5269}, year = {2011}, abstract = {The reliability of implantable blood sensors is often hampered by unspecific adsorption of plasma proteins and blood cells. This not only leads to a loss of sensor signal over time, but can also result in undesired host vs. graft reactions. Within this study we evaluated the hemocompatibility of isocyanate conjugated star shaped polytheylene oxide-polypropylene oxide co-polymers NCO-sP(EO-stat-PO) when applied to gold surfaces as an auspicious coating material for gold sputtered blood contacting sensors. Quartz crystal microbalance (QCM) sensors were coated with ultrathin NCO-sP(EO-stat-PO) films and compared with uncoated gold sensors. Protein resistance was assessed by QCM measurements with fibrinogen solution and platelet poor plasma (PPP), followed by quantification of fibrinogen adsorption. Hemocompatibility was tested by incubation with human platelet rich plasma (PRP). Thrombin antithrombin-III complex (TAT), beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) were used as coagulation activation markers. Furthermore, scanning electron microscopy (SEM) was used to visualize platelet adhesion to the sensor surfaces. Compared to uncoated gold sensors, NCO-sP(EO-stat-PO) coated sensors revealed significant better resistance against protein adsorption, lower TAT generation and a lower amount of adherent platelets. Moreover, coating with ultrathin NCO-sP(EO-stat-PO) films creates a cell resistant hemocompatible surface on gold that increases the chance of prolonged sensor functionality and can easily be modified with specific receptor molecules.}, language = {en} } @article{YinBrocherFischeretal.2011, author = {Yin, Jun and Brocher, Jan and Fischer, Utz and Winkler, Christoph}, title = {Mutant Prpf31 causes pre-mRNA splicing defects and rod photoreceptor cell degeneration in a zebrafish model for Retinitis pigmentosa}, series = {Molecular neurodegeneration}, volume = {6}, journal = {Molecular neurodegeneration}, number = {56}, doi = {10.1186/1750-1326-6-56}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141090}, pages = {1-17}, year = {2011}, abstract = {Background: Retinitis pigmentosa (RP) is an inherited eye disease characterized by the progressive degeneration of rod photoreceptor cells. Mutations in pre-mRNA splicing factors including PRPF31 have been identified as cause for RP, raising the question how mutations in general factors lead to tissue specific defects. Results: We have recently shown that the zebrafish serves as an excellent model allowing the recapitulation of key events of RP. Here we use this model to investigate two pathogenic mutations in PRPF31, SP117 and AD5, causing the autosomal dominant form of RP. We show that SP117 leads to an unstable protein that is mislocalized to the rod cytoplasm. Importantly, its overexpression does not result in photoreceptor degeneration suggesting haploinsufficiency as the underlying cause in human RP patients carrying SP117. In contrast, overexpression of AD5 results in embryonic lethality, which can be rescued by wild-type Prpf31. Transgenic retina-specific expression of AD5 reveals that stable AD5 protein is initially localized in the nucleus but later found in the cytoplasm concurrent with progressing rod outer segment degeneration and apoptosis. Importantly, we show for the first time in vivo that retinal transcripts are wrongly spliced in adult transgenic retinas expressing AD5 and exhibiting increased apoptosis in rod photoreceptors. Conclusion: Our data suggest that distinct mutations in Prpf31 can lead to photoreceptor degeneration through different mechanisms, by haploinsufficiency or dominant-negative effects. Analyzing the AD5 effects in our animal model in vivo, our data imply that aberrant splicing of distinct retinal transcripts contributes to the observed retina defects.}, language = {en} } @article{WedelHudakSeibeletal.2011, author = {Wedel, Steffen and Hudak, Lukasz and Seibel, Jens-Michael and Makarevic, Jasmina and Juengel, Eva and Tsaur, Igor and Waaga-Gasser, Ana and Haferkamp, Axel and Blaheta, Roman A.}, title = {Molecular targeting of prostate cancer cells by a triple drug combination down-regulates integrin driven adhesion processes, delays cell cycle progression and interferes with the cdk-cyclin axis}, series = {BMC Cancer}, volume = {11}, journal = {BMC Cancer}, number = {375}, doi = {10.1186/1471-2407-11-375}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141075}, pages = {1-14}, year = {2011}, abstract = {Background: Single drug use has not achieved satisfactory results in the treatment of prostate cancer, despite application of increasingly widespread targeted therapeutics. In the present study, the combined impact of the mammalian target of rapamycin (mTOR)-inhibitor RAD001, the dual EGFr and VGEFr tyrosine kinase inhibitor AEE788 and the histone deacetylase (HDAC)-inhibitor valproic acid (VPA) on prostate cancer growth and adhesion in vitro was investigated. Methods: PC-3, DU-145 and LNCaP cells were treated with RAD001, AEE788 or VPA or with a RAD-AEE-VPA combination. Tumor cell growth, cell cycle progression and cell cycle regulating proteins were then investigated by MTT-assay, flow cytometry and western blotting, respectively. Furthermore, tumor cell adhesion to vascular endothelium or to immobilized extracellular matrix proteins as well as migratory properties of the cells was evaluated, and integrin alpha and beta subtypes were analyzed. Finally, effects of drug treatment on cell signaling pathways were determined. Results: All drugs, separately applied, reduced tumor cell adhesion, migration and growth. A much stronger anticancer effect was evoked by the triple drug combination. Particularly, cdk1, 2 and 4 and cyclin B were reduced, whereas p27 was elevated. In addition, simultaneous application of RAD001, AEE788 and VPA altered the membranous, cytoplasmic and gene expression pattern of various integrin alpha and beta subtypes, reduced integrin-linked kinase (ILK) and deactivated focal adhesion kinase (FAK). Signaling analysis revealed that EGFr and the downstream target Akt, as well as p70S6k was distinctly modified in the presence of the drug combination. Conclusions: Simultaneous targeting of several key proteins in prostate cancer cells provides an advantage over targeting a single pathway. Since strong anti-tumor properties became evident with respect to cell growth and adhesion dynamics, the triple drug combination might provide progress in the treatment of advanced prostate cancer.}, language = {en} } @article{HillStritzkerScadengetal.2011, author = {Hill, Philip J. and Stritzker, Jochen and Scadeng, Miriam and Geissinger, Ulrike and Haddad, Daniel and Basse-L{\"u}sebrink, Thomas C. and Gbureck, Uwe and Jakob, Peter and Szalay, Aladar A.}, title = {Magnetic Resonance Imaging of Tumors Colonized with Bacterial Ferritin-Expressing \(Escherichia\) \(coli\)}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {10}, doi = {10.1371/journal.pone.0025409}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140920}, pages = {e25409}, year = {2011}, abstract = {Background: Recent studies have shown that human ferritin can be used as a reporter of gene expression for magnetic resonance imaging (MRI). Bacteria also encode three classes of ferritin-type molecules with iron accumulation properties. Methods and Findings: Here, we investigated whether these bacterial ferritins can also be used as MRI reporter genes and which of the bacterial ferritins is the most suitable reporter. Bacterial ferritins were overexpressed in probiotic E. coli Nissle 1917. Cultures of these bacteria were analyzed and those generating highest MRI contrast were further investigated in tumor bearing mice. Among members of three classes of bacterial ferritin tested, bacterioferritin showed the most promise as a reporter gene. Although all three proteins accumulated similar amounts of iron when overexpressed individually, bacterioferritin showed the highest contrast change. By site-directed mutagenesis we also show that the heme iron, a unique part of the bacterioferritin molecule, is not critical for MRI contrast change. Tumor-specific induction of bacterioferritin-expression in colonized tumors resulted in contrast changes within the bacteria-colonized tumors. Conclusions: Our data suggest that colonization and gene expression by live vectors expressing bacterioferritin can be monitored by MRI due to contrast changes.}, language = {en} } @article{BorisjukRolletschekFuchsetal.2011, author = {Borisjuk, Ljudmilla and Rolletschek, Hardy and Fuchs, Johannes and Melkus, Gerd and Neuberger, Thomas}, title = {Low and High Field Magnetic Resonance for \(in\) \(Vivo\) Analysis of Seeds}, series = {Materials}, volume = {4}, journal = {Materials}, number = {8}, doi = {10.3390/ma4081426}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140910}, pages = {1426-1439}, year = {2011}, abstract = {Low field NMR has been successfully used for the evaluation of seed composition and quality, but largely only in crop species. We show here that 1.5T NMR provides a reliable means for analysing the seed lipid fraction present in a wide range of species, where both the seed size and lipid concentration differed by >10 fold. Little use of high field NMR has been made in seed research to date, even though it potentially offers many opportunities for studying seed development, metabolism and storage. Here we demonstrate how 17.5T and 20T NMR can be applied to image seed structure, and analyse lipid and metabolite distribution. We suggest that further technical developments in NMR/MRI will facilitate significant advances in our understanding of seed biology.}, language = {en} } @article{BuchheimKellerKoetschanetal.2011, author = {Buchheim, Mark A. and Keller, Alexander and Koetschan, Christian and F{\"o}rster, Frank and Merget, Benjamin and Wolf, Matthias}, title = {Internal Transcribed Spacer 2 (nu ITS2 rRNA) Sequence-Structure Phylogenetics: Towards an Automated Reconstruction of the Green Algal Tree of Life}, series = {PLoS ONE}, volume = {6}, journal = {PLoS ONE}, number = {2}, doi = {10.1371/journal.pone.0016931}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140866}, pages = {e16931}, year = {2011}, abstract = {Background: Chloroplast-encoded genes (matK and rbcL) have been formally proposed for use in DNA barcoding efforts targeting embryophytes. Extending such a protocol to chlorophytan green algae, though, is fraught with problems including non homology (matK) and heterogeneity that prevents the creation of a universal PCR toolkit (rbcL). Some have advocated the use of the nuclear-encoded, internal transcribed spacer two (ITS2) as an alternative to the traditional chloroplast markers. However, the ITS2 is broadly perceived to be insufficiently conserved or to be confounded by introgression or biparental inheritance patterns, precluding its broad use in phylogenetic reconstruction or as a DNA barcode. A growing body of evidence has shown that simultaneous analysis of nucleotide data with secondary structure information can overcome at least some of the limitations of ITS2. The goal of this investigation was to assess the feasibility of an automated, sequence-structure approach for analysis of IT2 data from a large sampling of phylum Chlorophyta. Methodology/Principal Findings: Sequences and secondary structures from 591 chlorophycean, 741 trebouxiophycean and 938 ulvophycean algae, all obtained from the ITS2 Database, were aligned using a sequence structure-specific scoring matrix. Phylogenetic relationships were reconstructed by Profile Neighbor-Joining coupled with a sequence structure-specific, general time reversible substitution model. Results from analyses of the ITS2 data were robust at multiple nodes and showed considerable congruence with results from published phylogenetic analyses. Conclusions/Significance: Our observations on the power of automated, sequence-structure analyses of ITS2 to reconstruct phylum-level phylogenies of the green algae validate this approach to assessing diversity for large sets of chlorophytan taxa. Moreover, our results indicate that objections to the use of ITS2 for DNA barcoding should be weighed against the utility of an automated, data analysis approach with demonstrated power to reconstruct evolutionary patterns for highly divergent lineages.}, language = {en} } @article{HaddadChenZhangetal.2011, author = {Haddad, Dana and Chen, Nanhai G. and Zhang, Qian and Chen, Chun-Hao and Yu, Yong A. and Gonzalez, Lorena and Carpenter, Susanne G. and Carson, Joshua and Au, Joyce and Mittra, Arjun and Gonen, Mithat and Zanzonico, Pat B. and Fong, Yuman and Szalay, Aladar A.}, title = {Insertion of the human sodium iodide symporter to facilitate deep tissue imaging does not alter oncolytic or replication capability of a novel vaccinia virus}, series = {Journal of Translational Medicine}, volume = {9}, journal = {Journal of Translational Medicine}, number = {36}, doi = {10.1186/1479-5876-9-36}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140847}, pages = {1-14}, year = {2011}, abstract = {Introduction: Oncolytic viruses show promise for treating cancer. However, to assess therapeutic efficacy and potential toxicity, a noninvasive imaging modality is needed. This study aimed to determine if insertion of the human sodium iodide symporter (hNIS) cDNA as a marker for non-invasive imaging of virotherapy alters the replication and oncolytic capability of a novel vaccinia virus, GLV-1h153. Methods: GLV-1h153 was modified from parental vaccinia virus GLV-1h68 to carry hNIS via homologous recombination. GLV-1h153 was tested against human pancreatic cancer cell line PANC-1 for replication via viral plaque assays and flow cytometry. Expression and transportation of hNIS in infected cells was evaluated using Westernblot and immunofluorescence. Intracellular uptake of radioiodide was assessed using radiouptake assays. Viral cytotoxicity and tumor regression of treated PANC-1tumor xenografts in nude mice was also determined. Finally, tumor radiouptake in xenografts was assessed via positron emission tomography (PET) utilizing carrier-free (124)I radiotracer. Results: GLV-1h153 infected, replicated within, and killed PANC-1 cells as efficiently as GLV-1h68. GLV-1h153 provided dose-dependent levels of hNIS expression in infected cells. Immunofluorescence detected transport of the protein to the cell membrane prior to cell lysis, enhancing hNIS-specific radiouptake (P < 0.001). In vivo, GLV-1h153 was as safe and effective as GLV-1h68 in regressing pancreatic cancer xenografts (P < 0.001). Finally, intratumoral injection of GLV-1h153 facilitated imaging of virus replication in tumors via (124)I-PET. Conclusion: Insertion of the hNIS gene does not hinder replication or oncolytic capability of GLV-1h153, rendering this novel virus a promising new candidate for the noninvasive imaging and tracking of oncolytic viral therapy.}, language = {en} } @article{SbieraDexneitReichardtetal.2011, author = {Sbiera, Silviu and Dexneit, Thomas and Reichardt, Sybille D. and Michel, Kai D. and van den Brandt, Jens and Schmull, Sebastian and Kraus, Luitgard and Beyer, Melanie and Mlynski, Robert and Wortmann, Sebastian and Allolio, Bruno and Reichardt, Holger M. and Fassnacht, Martin}, title = {Influence of Short-Term Glucocorticoid Therapy on Regulatory T Cells \(In\) \(Vivo\)}, series = {PLoS One}, volume = {6}, journal = {PLoS One}, number = {9}, doi = {10.1371/journal.pone.0024345}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140822}, pages = {e24345}, year = {2011}, abstract = {Background: Pre- and early clinical studies on patients with autoimmune diseases suggested that induction of regulatory T(T(reg)) cells may contribute to the immunosuppressive effects of glucocorticoids(GCs). Objective: We readdressed the influence of GC therapy on T(reg) cells in immunocompetent human subjects and naive mice. Methods: Mice were treated with increasing doses of intravenous dexamethasone followed by oral taper, and T(reg) cells in spleen and blood were analyzed by FACS. Sixteen patients with sudden hearing loss but without an inflammatory disease received high-dose intravenous prednisolone followed by stepwise dose reduction to low oral prednisolone. Peripheral blood T(reg) cells were analyzed prior and after a 14 day GC therapy based on different markers. Results: Repeated GC administration to mice for three days dose-dependently decreased the absolute numbers of T(reg) cells in blood (100 mg dexamethasone/kg body weight: 2.8 +/- 1.8 x 10(4) cells/ml vs. 33 +/- 11 x 10(4) in control mice) and spleen (dexamethasone: 2.8 +/- 1.9 x 10(5)/spleen vs. 95 +/- 22 x 10(5)/spleen in control mice), which slowly recovered after 14 days taper in spleen but not in blood. The relative frequency of FOXP3(+) T(reg) cells amongst the CD4(+) T cells also decreased in a dose dependent manner with the effect being more pronounced in blood than in spleen. The suppressive capacity of T(reg) cells was unaltered by GC treatment in vitro. In immunocompetent humans, GCs induced mild T cell lymphocytosis. However, it did not change the relative frequency of circulating T(reg) cells in a relevant manner, although there was some variation depending on the definition of the T(reg) cells (FOXP3(+): 4.0 +/- 1.5\% vs 3.4 +/- 1.5\%*; AITR(+): 0.660.4 vs 0.5 +/- 0.3\%, CD127(low): 4.0 +/- 1.3 vs 5.0 +/- 3.0\%* and CTLA4+: 13.8 +/- 11.5 vs 15.6 +/- 12.5\%; * p < 0.05). Conclusion: Short-term GC therapy does not induce the hitherto supposed increase in circulating T(reg) cell frequency, neither in immunocompetent humans nor in mice. Thus, it is questionable that the clinical efficacy of GCs is achieved by modulating T(reg) cell numbers.}, language = {en} } @article{UppaluriNaglerStellamannsetal.2011, author = {Uppaluri, Sravanti and Nagler, Jan and Stellamanns, Eric and Heddergott, Niko and Herminghaus, Stephan and Pfohl, Thomas and Engstler, Markus}, title = {Impact of Microscopic Motility on the Swimming Behavior of Parasites: Straighter Trypanosomes are More Directional}, series = {PLoS Computational Biology}, volume = {7}, journal = {PLoS Computational Biology}, number = {6}, doi = {10.1371/journal.pcbi.1002058}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140814}, pages = {e1002058}, year = {2011}, abstract = {Microorganisms, particularly parasites, have developed sophisticated swimming mechanisms to cope with a varied range of environments. African Trypanosomes, causative agents of fatal illness in humans and animals, use an insect vector (the Tsetse fly) to infect mammals, involving many developmental changes in which cell motility is of prime importance. Our studies reveal that differences in cell body shape are correlated with a diverse range of cell behaviors contributing to the directional motion of the cell. Straighter cells swim more directionally while cells that exhibit little net displacement appear to be more bent. Initiation of cell division, beginning with the emergence of a second flagellum at the base, correlates to directional persistence. Cell trajectory and rapid body fluctuation correlation analysis uncovers two characteristic relaxation times: a short relaxation time due to strong body distortions in the range of 20 to 80 ms and a longer time associated with the persistence in average swimming direction in the order of 15 seconds. Different motility modes, possibly resulting from varying body stiffness, could be of consequence for host invasion during distinct infective stages.}, language = {en} } @article{GeisWeishauptGruenewaldetal.2011, author = {Geis, Christian and Weishaupt, Andreas and Gr{\"u}newald, Benedikt and Wultsch, Thomas and Reif, Andreas and Gerlach, Manfred and Dirkx, Ron and Solimena, Michele and Toyka, Klaus V and Folli, Franco and Perani, Daniela and Heckmann, Manfred and Sommer, Claudia}, title = {Human Stiff-Person Syndrome IgG Induces Anxious Behavior in Rats}, series = {Plos One}, volume = {6}, journal = {Plos One}, number = {2}, doi = {10.1371/journal.pone.0016775}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140506}, pages = {e16775}, year = {2011}, abstract = {Background: Anxiety is a heterogeneous behavioral domain playing a role in a variety of neuropsychiatric diseases. While anxiety is the cardinal symptom in disorders such as panic disorder, co-morbid anxious behavior can occur in a variety of diseases. Stiff person syndrome (SPS) is a CNS disorder characterized by increased muscle tone and prominent agoraphobia and anxiety. Most patients have high-titer antibodies against glutamate decarboxylase (GAD) 65. The pathogenic role of these autoantibodies is unclear. Methodology/Principal Findings: We re-investigated a 53 year old woman with SPS and profound anxiety for GABA-A receptor binding in the amygdala with (11) C-flumazenil PET scan and studied the potential pathogenic role of purified IgG from her plasma filtrates containing high-titer antibodies against GAD 65. We passively transferred the IgG fraction intrathecally into rats and analyzed the effects using behavioral and in vivo electrophysiological methods. In cell culture, we measured the effect of patient IgG on GABA release from hippocampal neurons. Repetitive intrathecal application of purified patient IgG in rats resulted in an anxious phenotype resembling the core symptoms of the patient. Patient IgG selectively bound to rat amygdala, hippocampus, and frontal cortical areas. In cultured rat hippocampal neurons, patient IgG inhibited GABA release. In line with these experimental results, the GABA-A receptor binding potential was reduced in the patient's amygdala/hippocampus complex. No motor abnormalities were found in recipient rats. Conclusion/Significance: The observations in rats after passive transfer lead us to propose that anxiety-like behavior can be induced in rats by passive transfer of IgG from a SPS patient positive for anti-GAD 65 antibodies. Anxiety, in this case, thus may be an antibody-mediated phenomenon with consecutive disturbance of GABAergic signaling in the amygdala region.}, language = {en} }