@article{KlaukeWinterGajewskaetal.2012, author = {Klauke, Benedikt and Winter, Bernward and Gajewska, Agnes and Zwanzger, Peter and Reif, Andreas and Herrmann, Martin J. and Dlugos, Andrea and Warrings, Bodo and Jacob, Christian and M{\"u}hlberger, Andreas and Arolt, Volker and Pauli, Paul and Deckert, J{\"u}rgen and Domschke, Katharina}, title = {Affect-Modulated Startle: Interactive Influence of Catechol-O-Methyltransferase Val158Met Genotype and Childhood Trauma}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {6}, doi = {10.1371/journal.pone.0039709}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132184}, pages = {e39709}, year = {2012}, abstract = {The etiology of emotion-related disorders such as anxiety or affective disorders is considered to be complex with an interaction of biological and environmental factors. Particular evidence has accumulated for alterations in the dopaminergic and noradrenergic system - partly conferred by catechol-O-methyltransferase (COMT) gene variation - for the adenosinergic system as well as for early life trauma to constitute risk factors for those conditions. Applying a multi-level approach, in a sample of 95 healthy adults, we investigated effects of the functional COMT Val158Met polymorphism, caffeine as an adenosine A2A receptor antagonist (300 mg in a placebo-controlled intervention design) and childhood maltreatment (CTQ) as well as their interaction on the affect-modulated startle response as a neurobiologically founded defensive reflex potentially related to fear- and distress-related disorders. COMT val/val genotype significantly increased startle magnitude in response to unpleasant stimuli, while met/met homozygotes showed a blunted startle response to aversive pictures. Furthermore, significant gene-environment interaction of COMT Val158Met genotype with CTQ was discerned with more maltreatment being associated with higher startle potentiation in val/val subjects but not in met carriers. No main effect of or interaction effects with caffeine were observed. Results indicate a main as well as a GxE effect of the COMT Val158Met variant and childhood maltreatment on the affect-modulated startle reflex, supporting a complex pathogenetic model of the affect-modulated startle reflex as a basic neurobiological defensive reflex potentially related to anxiety and affective disorders.}, language = {en} } @article{MichalskiHeindlKaczaetal.2012, author = {Michalski, D. and Heindl, M. and Kacza, J. and Laignel, F. and K{\"u}ppers-Tiedt, L. and Schneider, D. and Grosche, J. and Boltze, J. and L{\"o}hr, M. and Hobohm, C. and H{\"a}rtig, W.}, title = {Spatio-temporal course of macrophage-like cell accumulation after experimental embolic stroke depending on treatment with tissue plasminogen activator and its combination with hyperbaric oxygenation}, series = {European Journal of Histochemistry}, volume = {56}, journal = {European Journal of Histochemistry}, number = {2}, doi = {10.4081/ejh.2012.e14}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133136}, pages = {78 -- 89}, year = {2012}, abstract = {Inflammation following ischaemic stroke attracts high priority in current research, particularly using human-like models and long-term observation periods considering translational aspects. The present study aimed on the spatio-temporal course of macrophage-like cell accumulation after experimental thromboembolic stroke and addressed microglial and astroglial reactions in the ischaemic border zone. Further, effects of tissue plasminogen activator (tPA) as currently best treatment for stroke and the potentially neuroprotective co-administration of hyperbaric oxygen (HBO) were investigated. Rats underwent middle cerebral artery occlusion and were assigned to control, tPA or tPA+HBO. Twenty-four hours, 7, 14 and 28 days were determined as observation time points. The accumulation of macrophage-like cells was semiquantitatively assessed by CD68 staining in the ischaemic area and ischaemic border zone, and linked to the clinical course. CD11b, ionized calcium binding adaptor molecule 1 (Iba), glial fibrillary acidic protein (GFAP) and Neuronal Nuclei (NeuN) were applied to reveal delayed glial and neuronal alterations. In all groups, the accumulation of macrophage-like cells increased distinctly from 24 hours to 7 days post ischaemia. tPA+HBO tended to decrease macrophage-like cell accumulation at day 14 and 28. Overall, a trend towards an association of increased accumulation and pronounced reduction of the neurological deficit was found. Concerning delayed inflammatory reactions, an activation of microglia and astrocytes with co-occurring neuronal loss was observed on day 28. Thereby, astrogliosis was found circularly in contrast to microglial activation directly in the ischaemic area. This study supports previous data on long-lasting inflammatory processes following experimental stroke, and additionally provides region-specific details on glial reactions. The tendency towards a decreasing macrophage-like cell accumulation after tPA+HBO needs to be discussed critically since neuroprotective properties were recently ascribed to long-term inflammatory processes.}, language = {en} } @article{KesslerHertelJungkunstetal.2012, author = {Kessler, Michael and Hertel, Dietrich and Jungkunst, Hermann F. and Kluge, J{\"u}rgen and Abrahamczyk, Stefan and Bos, Merijn and Buchori, Damayanti and Gerold, Gerhard and Gradstein, S. Robbert and K{\"o}hler, Stefan and Leuschner, Christoph and Moser, Gerald and Pitopang, Ramadhanil and Saleh, Shahabuddin and Schulze, Christian H. and Sporn, Simone G. and Steffan-Dewenter, Ingolf and Tjitrosoedirdjo, Sri S. and Tscharntke, Teja}, title = {Can Joint Carbon and Biodiversity Management in Tropical Agroforestry Landscapes Be Optimized?}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {10}, doi = {10.1371/journal.pone.0047192}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132016}, pages = {e47192}, year = {2012}, abstract = {Managing ecosystems for carbon storage may also benefit biodiversity conservation, but such a potential 'win-win' scenario has not yet been assessed for tropical agroforestry landscapes. We measured above-and below-ground carbon stocks as well as the species richness of four groups of plants and eight of animals on 14 representative plots in Sulawesi, Indonesia, ranging from natural rainforest to cacao agroforests that have replaced former natural forest. The conversion of natural forests with carbon stocks of 227-362 Mg C ha\(^{-1}\) to agroforests with 82-211 Mg C ha\(^{-1}\) showed no relationships to overall biodiversity but led to a significant loss of forest-related species richness. We conclude that the conservation of the forest-related biodiversity, and to a lesser degree of carbon stocks, mainly depends on the preservation of natural forest habitats. In the three most carbon-rich agroforestry systems, carbon stocks were about 60\% of those of natural forest, suggesting that 1.6 ha of optimally managed agroforest can contribute to the conservation of carbon stocks as much as 1 ha of natural forest. However, agroforestry systems had comparatively low biodiversity, and we found no evidence for a tight link between carbon storage and biodiversity. Yet, potential win-win agroforestry management solutions include combining high shade-tree quality which favours biodiversity with cacao-yield adapted shade levels.}, language = {en} } @article{SpiveyDeGiorgiZhaoetal.2012, author = {Spivey, Tara L. and De Giorgi, Valeria and Zhao, Yingdong and Bedognetti, Davide and Pos, Zoltan and Liu, Qiuzhen and Tomei, Sara and Ascierto, Maria Libera and Uccellini, Lorenzo and Reinboth, Jennifer and Chouchane, Lotfi and Stroncek, David F. and Wang, Ena and Marincola, Francesco M.}, title = {The stable traits of melanoma genetics: an alternate approach to target discovery}, series = {BMC Genomics}, volume = {13}, journal = {BMC Genomics}, number = {156}, doi = {10.1186/1471-2164-13-156}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131992}, year = {2012}, abstract = {Background: The weight that gene copy number plays in transcription remains controversial; although in specific cases gene expression correlates with copy number, the relationship cannot be inferred at the global level. We hypothesized that genes steadily expressed by 15 melanoma cell lines (CMs) and their parental tissues (TMs) should be critical for oncogenesis and their expression most frequently influenced by their respective copy number. Results: Functional interpretation of 3,030 transcripts concordantly expressed (Pearson's correlation coefficient p-value < 0.05) by CMs and TMs confirmed an enrichment of functions crucial to oncogenesis. Among them, 968 were expressed according to the transcriptional efficiency predicted by copy number analysis (Pearson's correlation coefficient p-value < 0.05). We named these genes, "genomic delegates" as they represent at the transcriptional level the genetic footprint of individual cancers. We then tested whether the genes could categorize 112 melanoma metastases. Two divergent phenotypes were observed: one with prevalent expression of cancer testis antigens, enhanced cyclin activity, WNT signaling, and a Th17 immune phenotype (Class A). This phenotype expressed, therefore, transcripts previously associated to more aggressive cancer. The second class (B) prevalently expressed genes associated with melanoma signaling including MITF, melanoma differentiation antigens, and displayed a Th1 immune phenotype associated with better prognosis and likelihood to respond to immunotherapy. An intermediate third class (C) was further identified. The three phenotypes were confirmed by unsupervised principal component analysis. Conclusions: This study suggests that clinically relevant phenotypes of melanoma can be retraced to stable oncogenic properties of cancer cells linked to their genetic back bone, and offers a roadmap for uncovering novel targets for tailored anti-cancer therapy.}, language = {en} } @article{GalimbertiDell'OssoFenoglioetal.2012, author = {Galimberti, Daniela and Dell'Osso, Bernardo and Fenoglio, Chiara and Villa, Chiara and Cortini, Francesca and Serpente, Maria and Kittel-Schneider, Sarah and Weigl, Johannes and Neuner, Maria and Volkert, Juliane and Leonhard, C. and Olmes, David G. and Kopf, Juliane and Cantoni, Claudia and Ridolfi, Elisa and Palazzo, Carlotta and Ghezzi, Laura and Bresolin, Nereo and Altamura, A.C. and Scarpini, Elio and Reif, Andreas}, title = {Progranulin Gene Variability and Plasma Levels in Bipolar Disorder and Schizophrenia}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {4}, doi = {10.1371/journal.pone.0032164}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131910}, pages = {e32164}, year = {2012}, abstract = {Basing on the assumption that frontotemporal lobar degeneration (FTLD), schizophrenia and bipolar disorder (BPD) might share common aetiological mechanisms, we analyzed genetic variation in the FTLD risk gene progranulin (GRN) in a German population of patients with schizophrenia (n=271) or BPD (n=237) as compared with 574 age-, gender-and ethnicity-matched controls. Furthermore, we measured plasma progranulin levels in 26 German BPD patients as well as in 61 Italian BPD patients and 29 matched controls. A significantly decreased allelic frequency of the minor versus the wild-type allele was observed for rs2879096 (23.2 versus 34.2\%, P<0.001, OR: 0.63, 95\% CI: 0.49-0.80), rs4792938 (30.7 versus 39.7\%, P=0.005, OR: 0.70, 95\% CI: 0.55-0.89) and rs5848 (30.3 versus 36.8, P=0.007, OR: 0.71, 95\% CI: 0.56-0.91). Mean +/- SEM progranulin plasma levels were significantly decreased in BPD patients, either Germans or Italians, as compared with controls (89.69 +/- 3.97 and 116.14 +/- 5.80 ng/ml, respectively, versus 180.81 +/- 18.39 ng/ml P<0.001) and were not correlated with age. In conclusion, GRN variability decreases the risk to develop BPD and schizophrenia, and progranulin plasma levels are significantly lower in BPD patients than in controls. Nevertheless, a larger replication analysis would be needed to confirm these preliminary results.}, language = {en} } @article{NaseemDandekar2012, author = {Naseem, Muhammad and Dandekar, Thomas}, title = {The Role of Auxin-Cytokinin Antagonism in Plant-Pathogen Interactions}, series = {PLOS Pathogens}, volume = {8}, journal = {PLOS Pathogens}, number = {11}, doi = {10.1371/journal.ppat.1003026}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131901}, pages = {e1003026}, year = {2012}, abstract = {No abstract available.}, language = {en} } @article{SamimiFinkPaeth2012, author = {Samimi, C. and Fink, A. H. and Paeth, H.}, title = {The 2007 flood in the Sahel: causes, characteristics and its presentation in the media and FEWS NET}, series = {Natural Hazards and Earth System Sciences}, volume = {12}, journal = {Natural Hazards and Earth System Sciences}, number = {2}, doi = {10.5194/nhess-12-313-2012}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131790}, pages = {313 -- 325}, year = {2012}, abstract = {During the rainy season in 2007, reports about exceptional rains and floodings in the Sahel were published in the media, especially in August and September. Institutions and organizations like the World Food Programme (WFP) and FEWS NET put the events on the agenda and released alerts and requested help. The partly controversial picture was that most of the Sahel faced a crisis caused by widespread floodings. Our study shows that the rainy season in 2007 was exceptional with regard to rainfall amount and return periods. In many areas the event had a return period between 1 and 50 yr with high spatial heterogeneity, with the exception of the Upper Volta basin, which yielded return periods of up to 1200 yr. Despite the strong rainfall, the interpretation of satellite images show that the floods were mainly confined to lakes and river beds. However, the study also proves the difficulties in assessing the meteorological processes and the demarcation of flooded areas in satellite images without ground truthing. These facts and the somewhat vague and controversial reports in the media and FEWS NET demonstrate that it is crucial to thoroughly analyze such events at a regional and local scale involving the local population.}, language = {en} } @article{FernandezRodriguezQuilesBlancoetal.2012, author = {Fern{\´a}ndez-Rodr{\´i}guez, Juana and Quiles, Francisco and Blanco, Ignacio and Teul{\´e}, Alex and Feliubadal{\´o}, L{\´i}dia and del Valle, Jes{\´u}s and Salinas, M{\´o}nica and Izquierdo, {\´A}ngel and Darder, Esther and Schindler, Detlev and Capell{\´a}, Gabriel and Brunet, Joan and L{\´a}zaro, Conxi and Angel Pujana, Miguel}, title = {Analysis of SLX4/FANCP in non-BRCA1/2-mutated breast cancer families}, series = {BMC Cancer}, volume = {12}, journal = {BMC Cancer}, number = {84}, doi = {10.1186/1471-2407-12-84}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131772}, year = {2012}, abstract = {Background: Genes that, when mutated, cause Fanconi anemia or greatly increase breast cancer risk encode for proteins that converge on a homology-directed DNA damage repair process. Mutations in the SLX4 gene, which encodes for a scaffold protein involved in the repair of interstrand cross-links, have recently been identified in unclassified Fanconi anemia patients. A mutation analysis of SLX4 in German or Byelorussian familial cases of breast cancer without detected mutations in BRCA1 or BRCA2 has been completed, with globally negative results. Methods: The genomic region of SLX4, comprising all exons and exon-intron boundaries, was sequenced in 94 Spanish familial breast cancer cases that match a criterion indicating the potential presence of a highly-penetrant germline mutation, following exclusion of BRCA1 or BRCA2 mutations. Results: This mutational analysis revealed extensive genetic variation of SLX4, with 21 novel single nucleotide variants; however, none could be linked to a clear alteration of the protein function. Nonetheless, genotyping 10 variants (nine novel, all missense amino acid changes) in a set of controls (138 women and 146 men) did not detect seven of them. Conclusions: Overall, while the results of this study do not identify clearly pathogenic mutations of SLX4 contributing to breast cancer risk, further genetic analysis, combined with functional assays of the identified rare variants, may be warranted to conclusively assess the potential link with the disease.}, language = {en} } @article{SchneiderTautzGruenewaldetal.2012, author = {Schneider, Christof W. and Tautz, J{\"u}rgen and Gr{\"u}newald, Bernd and Fuchs, Stefan}, title = {RFID Tracking of Sublethal Effects of Two Neonicotinoid Insecticides on the Foraging Behavior of Apis mellifera}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0030023}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131753}, pages = {e30023}, year = {2012}, abstract = {The development of insecticides requires valid risk assessment procedures to avoid causing harm to beneficial insects and especially to pollinators such as the honeybee Apis mellifera. In addition to testing according to current guidelines designed to detect bee mortality, tests are needed to determine possible sublethal effects interfering with the animal's vitality and behavioral performance. Several methods have been used to detect sublethal effects of different insecticides under laboratory conditions using olfactory conditioning. Furthermore, studies have been conducted on the influence insecticides have on foraging activity and homing ability which require time-consuming visual observation. We tested an experimental design using the radiofrequency identification (RFID) method to monitor the influence of sublethal doses of insecticides on individual honeybee foragers on an automated basis. With electronic readers positioned at the hive entrance and at an artificial food source, we obtained quantifiable data on honeybee foraging behavior. This enabled us to efficiently retrieve detailed information on flight parameters. We compared several groups of bees, fed simultaneously with different dosages of a tested substance. With this experimental approach we monitored the acute effects of sublethal doses of the neonicotinoids imidacloprid (0.15-6 ng/bee) and clothianidin (0.05-2 ng/bee) under field-like circumstances. At field-relevant doses for nectar and pollen no adverse effects were observed for either substance. Both substances led to a significant reduction of foraging activity and to longer foraging flights at doses of >= 0.5 ng/bee (clothianidin) and >= 1.5 ng/bee (imidacloprid) during the first three hours after treatment. This study demonstrates that the RFID-method is an effective way to record short-term alterations in foraging activity after insecticides have been administered once, orally, to individual bees. We contribute further information on the understanding of how honeybees are affected by sublethal doses of insecticides.}, language = {en} } @article{PilsKoppPetersonetal.2012, author = {Pils, Stefan and Kopp, Kathrin and Peterson, Lisa and Tascon, Julia Delgado and Nyffenegger-Jann, Naja J. and Hauck, Christof R.}, title = {The Adaptor Molecule Nck Localizes the WAVE Complex to Promote Actin Polymerization during CEACAM3-Mediated Phagocytosis of Bacteria}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {3}, doi = {10.1371/journal.pone.0032808}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131747}, pages = {e32808}, year = {2012}, abstract = {Background: CEACAM3 is a granulocyte receptor mediating the opsonin-independent recognition and phagocytosis of human-restricted CEACAM-binding bacteria. CEACAM3 function depends on an intracellular immunoreceptor tyrosine-based activation motif (ITAM)-like sequence that is tyrosine phosphorylated by Src family kinases upon receptor engagement. The phosphorylated ITAM-like sequence triggers GTP-loading of Rac by directly associating with the guanine nucleotide exchange factor (GEF) Vav. Rac stimulation in turn is critical for actin cytoskeleton rearrangements that generate lamellipodial protrusions and lead to bacterial uptake. Principal Findings: In our present study we provide biochemical and microscopic evidence that the adaptor proteins Nck1 and Nck2, but not CrkL, Grb2 or SLP-76, bind to tyrosine phosphorylated CEACAM3. The association is phosphorylation-dependent and requires the Nck SH2 domain. Overexpression of the isolated Nck1 SH2 domain, RNAi-mediated knock-down of Nck1, or genetic deletion of Nck1 and Nck2 interfere with CEACAM3-mediated bacterial internalization and with the formation of lamellipodial protrusions. Nck is constitutively associated with WAVE2 and directs the actin nucleation promoting WAVE complex to tyrosine phosphorylated CEACAM3. In turn, dominant-negative WAVE2 as well as shRNA-mediated knock-down of WAVE2 or the WAVE-complex component Nap1 reduce internalization of bacteria. Conclusions: Our results provide novel mechanistic insight into CEACAM3-initiated phagocytosis. We suggest that the CEACAM3 ITAM-like sequence is optimized to co-ordinate a minimal set of cellular factors needed to efficiently trigger actin-based lamellipodial protrusions and rapid pathogen engulfment.}, language = {en} } @article{ZoephelReiherRexeretal.2012, author = {Zoephel, Judith and Reiher, Wencke and Rexer, Karl-Heinz and Kahnt, J{\"o}rg and Wegener, Christian}, title = {Peptidomics of the Agriculturally Damaging Larval Stage of the Cabbage Root Fly Delia radicum (Diptera: Anthomyiidae)}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {7}, doi = {10.1371/journal.pone.0041543}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131727}, pages = {e41543}, year = {2012}, abstract = {The larvae of the cabbage root fly induce serious damage to cultivated crops of the family Brassicaceae. We here report the biochemical characterisation of neuropeptides from the central nervous system and neurohemal organs, as well as regulatory peptides from enteroendocrine midgut cells of the cabbage maggot. By LC-MALDI-TOF/TOF and chemical labelling with 4-sulfophenyl isothiocyanate, 38 peptides could be identified, representing major insect peptide families: allatostatin A, allatostatin C, FMRFamide-like peptides, kinin, CAPA peptides, pyrokinins, sNPF, myosuppressin, corazonin, SIFamide, sulfakinins, tachykinins, NPLP1-peptides, adipokinetic hormone and CCHamide 1. We also report a new peptide (Yamide) which appears to be homolog to an amidated eclosion hormone-associated peptide in several Drosophila species. Immunocytochemical characterisation of the distribution of several classes of peptide-immunoreactive neurons and enteroendocrine cells shows a very similar but not identical peptide distribution to Drosophila. Since peptides regulate many vital physiological and behavioural processes such as moulting or feeding, our data may initiate the pharmacological testing and development of new specific peptide-based protection methods against the cabbage root fly and its larva.}, language = {en} } @article{SchwerkPapandreouSchuhmannetal.2012, author = {Schwerk, Christian and Papandreou, Thalia and Schuhmann, Daniel and Nickol, Laura and Borkowski, Julia and Steinmann, Ulrike and Quednau, Natascha and Stump, Carolin and Weiss, Christel and Berger, J{\"u}rgen and Wolburg, Hartwig and Claus, Heike and Vogel, Ulrich and Ishikawa, Hiroshi and Tenenbaum, Tobias and Schroten, Horst}, title = {Polar Invasion and Translocation of Neisseria meningitidis and Streptococcus suis in a Novel Human Model of the Blood-Cerebrospinal Fluid Barrier}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0030069}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131459}, pages = {e30069}, year = {2012}, abstract = {Acute bacterial meningitis is a life-threatening disease in humans. Discussed as entry sites for pathogens into the brain are the blood-brain and the blood-cerebrospinal fluid barrier (BCSFB). Although human brain microvascular endothelial cells (HBMEC) constitute a well established human in vitro model for the blood-brain barrier, until now no reliable human system presenting the BCSFB has been developed. Here, we describe for the first time a functional human BCSFB model based on human choroid plexus papilloma cells (HIBCPP), which display typical hallmarks of a BCSFB as the expression of junctional proteins and formation of tight junctions, a high electrical resistance and minimal levels of macromolecular flux when grown on transwell filters. Importantly, when challenged with the zoonotic pathogen Streptococcus suis or the human pathogenic bacterium Neisseria meningitidis the HIBCPP show polar bacterial invasion only from the physiologically relevant basolateral side. Meningococcal invasion is attenuated by the presence of a capsule and translocated N. meningitidis form microcolonies on the apical side of HIBCPP opposite of sites of entry. As a functionally relevant human model of the BCSFB the HIBCPP offer a wide range of options for analysis of disease-related mechanisms at the choroid plexus epithelium, especially involving human pathogens.}, language = {en} } @article{GassenBrechtefeldSchandryetal.2012, author = {Gassen, Alwine and Brechtefeld, Doris and Schandry, Niklas and Arteaga-Salas, J. Manuel and Israel, Lars and Imhof, Axel and Janzen, Christian J.}, title = {DOT1A-dependent H3K76 methylation is required for replication regulation in Trypanosoma brucei}, series = {Nucleic Acids Research}, volume = {40}, journal = {Nucleic Acids Research}, number = {20}, doi = {10.1093/nar/gks801}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131449}, pages = {10302 - 10311}, year = {2012}, abstract = {Cell-cycle progression requires careful regulation to ensure accurate propagation of genetic material to the daughter cells. Although many cell-cycle regulators are evolutionarily conserved in the protozoan parasite Trypanosoma brucei, novel regulatory mechanisms seem to have evolved. Here, we analyse the function of the histone methyltransferase DOT1A during cell-cycle progression. Over-expression of DOT1A generates a population of cells with aneuploid nuclei as well as enucleated cells. Detailed analysis shows that DOT1A over-expression causes continuous replication of the nuclear DNA. In contrast, depletion of DOT1A by RNAi abolishes replication but does not prevent karyokinesis. As histone H3K76 methylation has never been associated with replication control in eukaryotes before, we have discovered a novel function of DOT1 enzymes, which might not be unique to trypanosomes.}, language = {en} } @article{HafnerHoubenBaeurleetal.2012, author = {Hafner, Christian and Houben, Roland and Baeurle, Anne and Ritter, Cathrin and Schrama, David and Landthaler, Michael and Becker, J{\"u}rgen C.}, title = {Activation of the PI3K/AKT Pathway in Merkel Cell Carcinoma}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {2}, doi = {10.1371/journal.pone.0031255}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131398}, pages = {e31255}, year = {2012}, abstract = {Merkel cell carcinoma (MCC) is a highly aggressive skin cancer with an increasing incidence. The understanding of the molecular carcinogenesis of MCC is limited. Here, we scrutinized the PI3K/AKT pathway, one of the major pathways activated in human cancer, in MCC. Immunohistochemical analysis of 41 tumor tissues and 9 MCC cell lines revealed high levels of AKT phosphorylation at threonine 308 in 88\% of samples. Notably, the AKT phosphorylation was not correlated with the presence or absence of the Merkel cell polyoma virus (MCV). Accordingly, knock-down of the large and small T antigen by shRNA in MCV positive MCC cells did not affect phosphorylation of AKT. We also analyzed 46 MCC samples for activating PIK3CA and AKT1 mutations. Oncogenic PIK3CA mutations were found in 2/46 (4\%) MCCs whereas mutations in exon 4 of AKT1 were absent. MCC cell lines demonstrated a high sensitivity towards the PI3K inhibitor LY-294002. This finding together with our observation that the PI3K/AKT pathway is activated in the majority of human MCCs identifies PI3K/AKT as a potential new therapeutic target for MCC patients.}, language = {en} } @article{vanKoolwijkRamdasIkrametal.2012, author = {van Koolwijk, Leonieke M. E. and Ramdas, Wishal D. and Ikram, M. Kamran and Jansonius, Nomdo M. and Pasutto, Francesca and Hys, Pirro G. and Macgregor, Stuart and Janssen, Sarah F. and Hewitt, Alex W. and Viswanathan, Ananth C. and ten Brink, Jacoline B. and Hosseini, S. Mohsen and Amin, Najaf and Despriet, Dominiek D. G. and Willemse-Assink, Jacqueline J. M. and Kramer, Rogier and Rivadeneira, Fernando and Struchalin, Maksim and Aulchenko, Yurii S. and Weisschuh, Nicole and Zenkel, Matthias and Mardin, Christian Y. and Gramer, Eugen and Welge-L{\"u}ssen, Ulrich and Montgomery, Grant W. and Carbonaro, Francis and Young, Terri L. and Bellenguez, C{\´e}line and McGuffin, Peter and Foster, Paul J. and Topouzis, Fotis and Mitchell, Paul and Wang, Jie Jin and Wong, Tien Y. and Czudowska, Monika A. and Hofman, Albert and Uitterlinden, Andre G. and Wolfs, Roger C. W. and de Jong, Paulus T. V. M. and Oostra, Ben A. and Paterson, Andrew D. and Mackey, David A. and Bergen, Arthur A. B. and Reis, Andre and Hammond, Christopher J. and Vingerling, Johannes R. and Lemij, Hans G. and Klaver, Caroline C. W. and van Duijn, Cornelia M.}, title = {Common Genetic Determinants of Intraocular Pressure and Primary Open-Angle Glaucoma}, series = {PLoS Genetics}, volume = {8}, journal = {PLoS Genetics}, number = {5}, doi = {10.1371/journal.pgen.1002611}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131378}, pages = {e1002611}, year = {2012}, abstract = {Intraocular pressure (IOP) is a highly heritable risk factor for primary open-angle glaucoma and is the only target for current glaucoma therapy. The genetic factors which determine IOP are largely unknown. We performed a genome-wide association study for IOP in 11,972 participants from 4 independent population-based studies in The Netherlands. We replicated our findings in 7,482 participants from 4 additional cohorts from the UK, Australia, Canada, and the Wellcome Trust Case-Control Consortium 2/Blue Mountains Eye Study. IOP was significantly associated with rs11656696, located in GAS7 at 17p13.1 (p = 1.4 x 10\(^{-8}\)), and with rs7555523, located in TMCO1 at 1q24.1 (p = 1.6 x 10\(^{-8}\)). In a meta-analysis of 4 case-control studies (total N = 1,432 glaucoma cases), both variants also showed evidence for association with glaucoma (p = 2.4 x 10\(^{-2}\) for rs11656696 and p = 9.1 x 10\(^{-4}\) for rs7555523). GAS7 and TMCO1 are highly expressed in the ciliary body and trabecular meshwork as well as in the lamina cribrosa, optic nerve, and retina. Both genes functionally interact with known glaucoma disease genes. These data suggest that we have identified two clinically relevant genes involved in IOP regulation.}, language = {en} } @article{StaigerCadotKooteretal.2012, author = {Staiger, Christine and Cadot, Sidney and Kooter, Raul and Dittrich, Marcus and M{\"u}ller, Tobias and Klau, Gunnar W. and Wessels, Lodewyk F. A.}, title = {A Critical Evaluation of Network and Pathway-Based Classifiers for Outcome Prediction in Breast Cancer}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {4}, doi = {10.1371/journal.pone.0034796}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131323}, pages = {e34796}, year = {2012}, abstract = {Recently, several classifiers that combine primary tumor data, like gene expression data, and secondary data sources, such as protein-protein interaction networks, have been proposed for predicting outcome in breast cancer. In these approaches, new composite features are typically constructed by aggregating the expression levels of several genes. The secondary data sources are employed to guide this aggregation. Although many studies claim that these approaches improve classification performance over single genes classifiers, the gain in performance is difficult to assess. This stems mainly from the fact that different breast cancer data sets and validation procedures are employed to assess the performance. Here we address these issues by employing a large cohort of six breast cancer data sets as benchmark set and by performing an unbiased evaluation of the classification accuracies of the different approaches. Contrary to previous claims, we find that composite feature classifiers do not outperform simple single genes classifiers. We investigate the effect of (1) the number of selected features; (2) the specific gene set from which features are selected; (3) the size of the training set and (4) the heterogeneity of the data set on the performance of composite feature and single genes classifiers. Strikingly, we find that randomization of secondary data sources, which destroys all biological information in these sources, does not result in a deterioration in performance of composite feature classifiers. Finally, we show that when a proper correction for gene set size is performed, the stability of single genes sets is similar to the stability of composite feature sets. Based on these results there is currently no reason to prefer prognostic classifiers based on composite features over single genes classifiers for predicting outcome in breast cancer.}, language = {en} } @article{GrassmannFritscheKeilhaueretal.2012, author = {Grassmann, Felix and Fritsche, Lars G. and Keilhauer, Claudia N. and Heid, Iris M. and Weber, Bernhard H. F.}, title = {Modelling the Genetic Risk in Age-Related Macular Degeneration}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {5}, doi = {10.1371/journal.pone.0037979}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131315}, pages = {e37979}, year = {2012}, abstract = {Late-stage age-related macular degeneration (AMD) is a common sight-threatening disease of the central retina affecting approximately 1 in 30 Caucasians. Besides age and smoking, genetic variants from several gene loci have reproducibly been associated with this condition and likely explain a large proportion of disease. Here, we developed a genetic risk score (GRS) for AMD based on 13 risk variants from eight gene loci. The model exhibited good discriminative accuracy, area-under-curve (AUC) of the receiver-operating characteristic of 0.820, which was confirmed in a cross-validation approach. Noteworthy, younger AMD patients aged below 75 had a significantly higher mean GRS (1.87, 95\% CI: 1.69-2.05) than patients aged 75 and above (1.45, 95\% CI: 1.36-1.54). Based on five equally sized GRS intervals, we present a risk classification with a relative AMD risk of 64.0 (95\% CI: 14.11-1131.96) for individuals in the highest category (GRS 3.44-5.18, 0.5\% of the general population) compared to subjects with the most common genetic background (GRS -0.05-1.70, 40.2\% of general population). The highest GRS category identifies AMD patients with a sensitivity of 7.9\% and a specificity of 99.9\% when compared to the four lower categories. Modeling a general population around 85 years of age, 87.4\% of individuals in the highest GRS category would be expected to develop AMD by that age. In contrast, only 2.2\% of individuals in the two lowest GRS categories which represent almost 50\% of the general population are expected to manifest AMD. Our findings underscore the large proportion of AMD cases explained by genetics particularly for younger AMD patients. The five-category risk classification could be useful for therapeutic stratification or for diagnostic testing purposes once preventive treatment is available.}, language = {en} } @article{JainJavdanFegeretal.2012, author = {Jain, Preetesh and Javdan, Mohammad and Feger, Franziska K. and Chiu, Pui Yan and Sison, Cristina and Damle, Rajendra N. and Bhuiya, Tawfiqul A. and Sen, Filiz and Abruzzo, Lynne V. and Burger, Jan A. and Rosenwald, Andreas and Allen, Steven L. and Kolitz, Jonathan E. and Rai, Kanti R. and Chiorazzi, Nicholas and Sherry, Barbara}, title = {Th17 and non-Th17 interleukin-17-expressing cells in chronic lymphocytic leukemia: delineation, distribution, and clinical relevance}, series = {Haematologica}, volume = {97}, journal = {Haematologica}, number = {4}, doi = {10.3324/haematol.2011.047316}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131290}, pages = {599 - 607}, year = {2012}, abstract = {Background The levels and clinical relevance of Th17 cells and other interleukin-17-producing cells have not been analyzed in chronic lymphocytic leukemia. The objective of this study was to quantify blood and tissue levels of Th17 and other interleukin-17-producing cells in patients with this disease and correlate blood levels with clinical outcome. Design and Methods: Intracellular interleukin-17A was assessed in blood and splenic mononuclear cells from patients with chronic lymphocytic leukemia and healthy subjects using flow cytometry. Interleukin-17A-producing cells were analyzed in formalin-fixed, paraffin-embedded spleen and lymph node sections using immunohistochemistry and immunofluorescence. Results: The absolute numbers of Th17 cells in peripheral blood mononuclear cells and the percentages of Th17 cells in spleen cell suspensions were higher in patients with chronic lymphocytic leukemia than in healthy subjects; in six out of eight paired chronic lymphocytic leukemia blood and spleen sample comparisons, Th17 cells were enriched in spleen suspensions. Circulating Th17 levels correlated with better prognostic markers and longer overall survival of the patients. Two "non-Th17" interleukin-17-expressing cells were identified in chronic lymphocytic leukemia spleens: proliferating cells of the granulocytic lineage and mature mast cells. Granulocytes and mast cells in normal spleens did not express interleukin-17. Conversely, both chronic lymphocytic leukemia and healthy lymph nodes contained similar numbers of interleukin-17+ mast cells as well as Th17 cells. Conclusions: Th17 cells are elevated in chronic lymphocytic leukemia patients with better prognostic markers and correlate with longer survival. Furthermore, non-Th17 interleukin-17A-expressing cells exist in chronic lymphocytic leukemia spleens as maturing granulocytes and mature mast cells, suggesting that the microenvironmental milieu in leukemic spleens promotes the recruitment and/or expansion of Th17 and other IL-17-expressing cells. The pathophysiology of Th17 and non-Th17-interleukin-producing cells in chronic lymphocytic leukemia and their distributions and roles in this disease merit further study.}, language = {en} } @article{BoehlerCreignouGalotaetal.2012, author = {B{\"o}hler, Elmar and Creignou, Nadia and Galota, Matthias and Reith, Steffen and Schnoor, Henning and Vollmer, Heribert}, title = {Complexity Classifications for Different Equivalence and Audit Problems for Boolean Circuits}, series = {Logical Methods in Computer Science}, volume = {8}, journal = {Logical Methods in Computer Science}, number = {3:27}, doi = {10.2168/LMCS-8(3:27)2012}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131121}, pages = {1 -- 25}, year = {2012}, abstract = {We study Boolean circuits as a representation of Boolean functions and conskier different equivalence, audit, and enumeration problems. For a number of restricted sets of gate types (bases) we obtain efficient algorithms, while for all other gate types we show these problems are at least NP-hard.}, language = {en} } @article{HofgaardJodalBommertetal.2012, author = {Hofgaard, Peter O. and Jodal, Henriette C. and Bommert, Kurt and Huard, Bertrand and Caers, Jo and Carlsen, Harald and Schwarzer, Rolf and Sch{\"u}nemann, Nicole and Jundt, Franziska and Lindeberg, Mona M. and Bogen, Bjarne}, title = {A Novel Mouse Model for Multiple Myeloma (MOPC315.BM) That Allows Noninvasive Spatiotemporal Detection of Osteolytic Disease}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {12}, doi = {10.1371/journal.pone.0051892}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131117}, pages = {e51892}, year = {2012}, abstract = {Multiple myeloma (MM) is a lethal human cancer characterized by a clonal expansion of malignant plasma cells in bone marrow. Mouse models of human MM are technically challenging and do not always recapitulate human disease. Therefore, new mouse models for MM are needed. Mineral-oil induced plasmacytomas (MOPC) develop in the peritoneal cavity of oil-injected BALB/c mice. However, MOPC typically grow extramedullary and are considered poor models of human MM. Here we describe an in vivo-selected MOPC315 variant, called MOPC315.BM, which can be maintained in vitro. When injected i.v. into BALB/c mice, MOPC315.BM cells exhibit tropism for bone marrow. As few as 10\(^4\) MOPC315.BM cells injected i.v. induced paraplegia, a sign of spinal cord compression, in all mice within 3-4 weeks. MOPC315.BM cells were stably transfected with either firefly luciferase (MOPC315.BM.Luc) or DsRed (MOPC315.BM.DsRed) for studies using noninvasive imaging. MOPC315.BM.Luc cells were detected in the tibiofemoral region already 1 hour after i.v. injection. Bone foci developed progressively, and as of day 5, MM cells were detected in multiple sites in the axial skeleton. Additionally, the spleen (a hematopoietic organ in the mouse) was invariably affected. Luminescent signals correlated with serum myeloma protein concentration, allowing for easy tracking of tumor load with noninvasive imaging. Affected mice developed osteolytic lesions. The MOPC315.BM model employs a common strain of immunocompetent mice (BALB/c) and replicates many characteristics of human MM. The model should be suitable for studies of bone marrow tropism, development of osteolytic lesions, drug testing, and immunotherapy in MM.}, language = {en} }