TY - JOUR A1 - Boltze, Johannes A1 - Kleinschnitz, Christoph A1 - Reymann, Klaus G. A1 - Reiser, Georg A1 - Wagner, Daniel-Christoph A1 - Kranz, Alexander A1 - Michalski, Dominik T1 - Neurovascular pathophysiology in cerebral ischemia, dementia and the ageing brain – current trends in basic, translational and clinical research JF - Experimental & Translational Stroke Medicine N2 - The 7th International Symposium on Neuroprotection and Neurorepair was held from May 2nd to May 5th, 2012 in Potsdam, Germany. The symposium, which directly continues the successful Magdeburg meeting series, attracted over 330 colleagues from 29 countries to discuss recent findings and advances in the field. The focus of the 2012 symposium was widened from stroke and traumatic brain injury to neurodegenerative diseases, notably dementia, and more generally the ageing brain. Thereby, emphasis was given on neurovascular aspects of neurodegeneration and stroke including the blood–brain barrier, recent findings regarding the pathomechanism of Alzheimer’s disease, and brain imaging approaches. In addition, neurobiochemical aspects of neuroprotection, the role of astrogliosis, the clinical progress of cell-based approaches as well as translational hurdles and opportunities were discussed in-depth. This review summarizes some of the most stimulating discussions and reports from the meeting. KW - translational research KW - small vessel disease KW - Alzheimer’s disease KW - cerebral ischemia KW - neurorepair KW - neuroprotection KW - vascular dementia KW - mitochondria KW - astrogliosis KW - in vivo imaging Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126679 VL - 4 IS - 14 ER - TY - JOUR A1 - Pandurangan, Sudhakar A1 - Pajak, Agnieszka A1 - Molnar, Stephen J. A1 - Cober, Elroy R. A1 - Dhaubhadel, Sangeeta A1 - Hernández-Sebastià, Cinta A1 - Kaiser, Werner M. A1 - Nelson, Randall L. A1 - Huber, Steven C. A1 - Marsolais, Frédéric T1 - Relationship between asparagine metabolism and protein concentration in soybean seed JF - Journal of Experimental Botany N2 - The relationship between asparagine metabolism and protein concentration was investigated in soybean seed. Phenotyping of a population of recombinant inbred lines adapted to Illinois confirmed a positive correlation between free asparagine levels in developing seeds and protein concentration at maturity. Analysis of a second population of recombinant inbred lines adapted to Ontario associated the elevated free asparagine trait with two of four quantitative trait loci determining population variation for protein concentration, including a major one on chromosome 20 (linkage group I) which has been reported in multiple populations. In the seed coat, levels of asparagine synthetase were high at 50 mg and progressively declined until 150 mg seed weight, suggesting that nitrogenous assimilates are pre-conditioned at early developmental stages to enable a high concentration of asparagine in the embryo. The levels of asparaginase B1 showed an opposite pattern, being low at 50 mg and progressively increased until 150 mg, coinciding with an active phase of storage reserve accumulation. In a pair of genetically related cultivars, ∼2-fold higher levels of asparaginase B1 protein and activity in seed coat, were associated with high protein concentration, reflecting enhanced flux of nitrogen. Transcript expression analyses attributed this difference to a specific asparaginase gene, ASPGB1a. These results contribute to our understanding of the processes determining protein concentration in soybean seed. KW - soybean KW - seed protein concentration KW - quantitative trait locus KW - asparagine synthetase KW - asparagine KW - asparaginase Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126900 VL - 63 IS - 8 ER - TY - JOUR A1 - Yamakawa, Hisanori A1 - Fukushima, Yoshimasa A1 - Itoh, Shigeru A1 - Heber, Ulrich T1 - Three different mechanisms of energy dissipation of a desiccation-tolerant moss serve one common purpose: to protect reaction centres against photo-oxidation JF - Journal of Experimental Botany N2 - Three different types of non-photochemical de-excitation of absorbed light energy protect photosystem II of the sun- and desiccation-tolerant moss Rhytidium rugosum against photo-oxidation. The first mechanism, which is light-induced in hydrated thalli, is sensitive to inhibition by dithiothreitol. It is controlled by the protonation of a thylakoid protein. Other mechanisms are activated by desiccation. One of them permits exciton migration towards a far-red band in the antenna pigments where fast thermal deactivation takes place. This mechanism appears to be similar to a mechanism detected before in desiccated lichens. A third mechanism is based on the reversible photo-accumulation of a radical that acts as a quencher of excitation energy in reaction centres of photosystem II. On the basis of absorption changes around 800 nm, the quencher is suggested to be an oxidized chlorophyll. The data show that desiccated moss is better protected against photo-oxidative damage than hydrated moss. Slow drying of moss thalli in the light increases photo-protection more than slow drying in darkness. KW - reaction centre KW - photoprotection KW - energy dissipation KW - energy conservation KW - chlorophyll fluorescence KW - photosystem II Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126897 VL - 63 IS - 10 ER - TY - JOUR A1 - Azzami, Klara A1 - Ritter, Wolfgang A1 - Tautz, Jürgen A1 - Beier, Hildburg T1 - Infection of honey bees with acute bee paralysis virus does not trigger humoral or cellular immune responses JF - Archives of Virology N2 - We have studied the responses of honey bees at different life stages (Apis mellifera) to controlled infection with acute bee paralysis virus and have identified the haemolymph of infected larvae and adult worker bees as the compartment where massive propagation of ABPV occurs. Insects respond with a broad spectrum of induced innate immune reactions to bacterial infections, whereas defence mechanisms based on RNA interference play a major role in antiviral immunity. In this study, we have determined that honey bee larvae and adult workers do not produce a humoral immune reaction upon artificial infection with ABPV, in contrast to control individuals challenged with Escherichia coli. ABPV-infected bees produced neither elevated levels of specific antimicrobial peptides (AMPs), such as hymenoptaecin and defensin, nor any general antimicrobial activity, as revealed by inhibition-zone assays. Additionally, adult bees did not generate melanised nodules upon ABPV infection, an important cellular immune function activated by bacteria and viruses in some insects. Challenge of bees with both ABPV and E. coli showed that innate humoral and cellular immune reactions are induced in mixed infections, albeit at a reduced level. KW - chemosensory protein KW - bee larva KW - adult bee KW - honey bee KW - larva KW - work bee KW - infected bee KW - immune response KW - young work bee KW - capsid protein KW - abdominal KW - tergite KW - haemolymph KW - sample KW - Imd pathway KW - worker bee larva KW - antimicrobial KW - peptide Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126863 VL - 157 IS - 4 ER - TY - JOUR A1 - Conzelmann, Annette A1 - Reif, Andreas A1 - Jacob, Christian A1 - Weyers, Peter A1 - Lesch, Klaus-Peter A1 - Lutz, Beat A1 - Pauli, Paul T1 - A polymorphism in the gene of the endocannabinoid-degrading enzyme FAAH (FAAH C385A) is associated with emotional-motivational reactivity JF - Psychopharmacology N2 - RATIONALE: The endocannabinoid (eCB) system is implicated in several psychiatric disorders. Investigating emotional-motivational dysfunctions as underlying mechanisms, a study in humans revealed that in the C385A polymorphism of the fatty acid amide hydrolase (FAAH), the degrading enzyme of the eCB anandamide (AEA), A carriers, who are characterized by increased signaling of AEA as compared to C/C carriers, exhibited reduced brain reactivity towards unpleasant faces and enhanced reactivity towards reward. However, the association of eCB system with emotional-motivational reactivity is complex and bidirectional due to upcoming compensatory processes. OBJECTIVES: Therefore, we further investigated the relationship of the FAAH polymorphism and emotional-motivational reactivity in humans. METHODS: We assessed the affect-modulated startle, and ratings of valence and arousal in response to higher arousing pleasant, neutral, and unpleasant pictures in 67 FAAH C385A C/C carriers and 45 A carriers. RESULTS: Contrarily to the previous functional MRI study, A carriers compared to C/C carriers exhibited an increased startle potentiation and therefore emotional responsiveness towards unpleasant picture stimuli and reduced startle inhibition indicating reduced emotional reactivity in response to pleasant pictures, while both groups did not differ in ratings of arousal and valence. CONCLUSIONS: Our findings emphasize the bidirectionality and thorough examination of the eCB system's impact on emotional reactivity as a central endophenotype underlying various psychiatric disorders. KW - startle reflex KW - endocannabinoid KW - FAAH KW - genetics KW - emotion Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126845 VL - 224 IS - 4 ER - TY - JOUR A1 - Muysoms, F. A1 - Campanelli, G. A1 - Champault, G. A1 - DeBeaux, A. C. A1 - Dietz, U. A. A1 - Jeekel, J. A1 - Klinge, U. A1 - Käckerling, F. A1 - Mandala, M. A1 - Montgomery, A. A1 - Morales Conde, S. A1 - Puppe, F. A1 - Simmermacher, R. K. J. A1 - Asmieta Aski, M. A1 - Miserez, M. T1 - EuraHS: the development of an international online platform for registration and outcome measurement of ventral abdominal wall hernia repair JF - Hernia N2 - BACKGROUND: Although the repair of ventral abdominal wall hernias is one of the most commonly performed operations, many aspects of their treatment are still under debate or poorly studied. In addition, there is a lack of good definitions and classifications that make the evaluation of studies and meta-analyses in this field of surgery difficult. MATERIALS AND METHODS: Under the auspices of the board of the European Hernia Society and following the previously published classifications on inguinal and on ventral hernias, a working group was formed to create an online platform for registration and outcome measurement of operations for ventral abdominal wall hernias. Development of such a registry involved reaching agreement about clear definitions and classifications on patient variables, surgical procedures and mesh materials used, as well as outcome parameters. The EuraHS working group (European registry for abdominal wall hernias) comprised of a multinational European expert panel with specific interest in abdominal wall hernias. Over five working group meetings, consensus was reached on definitions for the data to be recorded in the registry. RESULTS: A set of well-described definitions was made. The previously reported EHS classifications of hernias will be used. Risk factors for recurrences and co-morbidities of patients were listed. A new severity of comorbidity score was defined. Post-operative complications were classified according to existing classifications as described for other fields of surgery. A new 3-dimensional numerical quality-of-life score, EuraHS-QoL score, was defined. An online platform is created based on the definitions and classifications, which can be used by individual surgeons, surgical teams or for multicentre studies. A EuraHS website is constructed with easy access to all the definitions, classifications and results from the database. CONCLUSION: An online platform for registration and outcome measurement of abdominal wall hernia repairs with clear definitions and classifications is offered to the surgical community. It is hoped that this registry could lead to better evidence-based guidelines for treatment of abdominal wall hernias based on hernia variables, patient variables, available hernia repair materials and techniques. KW - abdominal wall hernia KW - ventral hernia model KW - abdominal wall surgery KW - Mesh Augmentation KW - EHS classification KW - femoral hernia KW - inguinal hernia KW - recurrent abdominal wall hernia KW - mesh augmentation KW - hernia defect KW - mesh repair KW - incisional abdominal wall hernia KW - primary ventral hernia KW - parastomal hernia KW - Danish hernia database KW - hernia repair material Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126691 VL - 16 IS - 3 ER - TY - JOUR A1 - Chen, Wen A1 - Gaßner, Birgit A1 - Börner, Sebastian A1 - Nikolaev, Viacheslav O. A1 - Schlegel, Nicolas A1 - Waschke, Jens A1 - Steinbronn, Nadine A1 - Strasser, Ruth A1 - Kuhn, Michaela T1 - Atrial natriuretic peptide enhances microvascular albumin permeability by the caveolae-mediated transcellular pathway JF - Cardiovascular Research N2 - Aims Cardiac atrial natriuretic peptide (ANP) participates in the maintenance of arterial blood pressure and intravascular volume homeostasis. The hypovolaemic effects of ANP result from coordinated actions in the kidney and systemic microcirculation. Hence, ANP, via its guanylyl cyclase-A (GC-A) receptor and intracellular cyclic GMP as second messenger, stimulates endothelial albumin permeability. Ultimately, this leads to a shift of plasma fluid into interstitial pools. Here we studied the role of caveolae-mediated transendothelial albumin transport in the hyperpermeability effects of ANP. Methods and results Intravital microscopy studies of the mouse cremaster microcirculation showed that ANP stimulates the extravasation of fluorescent albumin from post-capillary venules and causes arteriolar vasodilatation. The hyperpermeability effect was prevented in mice with conditional, endothelial deletion of GC-A (EC GC-A KO) or with deleted caveolin-1 (cav-1), the caveolae scaffold protein. In contrast, the vasodilating effect was preserved. Concomitantly, the acute hypovolaemic action of ANP was abolished in EC GC-A KO and Cav-1−/− mice. In cultured microvascular rat fat pad and mouse lung endothelial cells, ANP stimulated uptake and transendothelial transport of fluorescent albumin without altering endothelial electrical resistance. The stimulatory effect on albumin uptake was prevented in GC-A- or cav-1-deficient pulmonary endothelia. Finally, preparation of caveolin-enriched lipid rafts from mouse lung and western blotting showed that GC-A and cGMP-dependent protein kinase I partly co-localize with Cav-1 in caveolae microdomains. Conclusion ANP enhances transendothelial caveolae-mediated albumin transport via its GC-A receptor. This ANP-mediated cross-talk between the heart and the microcirculation is critically involved in the regulation of intravascular volume. KW - caveolin-1 KW - microvessel permeability KW - atrial natriuretic peptide Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126562 N1 - Lizenzhinweis: The online version of this article has been published under an open access model. Users are entitled to use, reproduce, disseminate, or display the open access version of this article for noncommercial purposes provided that the original authorship is properly and fully attributed; the Journal, Learned Society and Oxford University Press are attributed as the original place of publication with correct citation details given; if an article is subsequently reproduced or disseminated not in its entirety but only in part or as a derivative work this must be clearly indicated. VL - 93 IS - 1 ER - TY - JOUR A1 - Kraft, Peter A1 - De Meyer, Simon F. A1 - Kleinschnitz, Christoph T1 - Next-Generation Antithrombotics in Ischemic Stroke: Preclinical Perspective on ‘Bleeding-Free Antithrombosis’ JF - Journal of Cerebral Blood Flow and Metabolism N2 - The present antithrombotic drugs used to treat or prevent ischemic stroke have significant limitations: either they show only moderate efficacy (platelet inhibitors), or they significantly increase the risk for hemorrhages (thrombolytics, anticoagulants). Although most strokes are caused by thrombotic or embolic vessel occlusions, the pathophysiological role of platelets and coagulation is largely unclear. The introduction of novel transgenic mouse models and specific coagulation inhibitors facilitated a detailed analysis of molecular pathways mediating thrombus formation in models of acute ischemic stroke. Prevention of early platelet adhesion to the damaged vessel wall by blocking platelet surface receptors glycoprotein Ib alpha (GPIbα) or glycoprotein VI (GPVI) protects from stroke without provoking bleeding complications. In addition, downstream signaling of GPIbα and GPVI has a key role in platelet calcium homeostasis and activation. Finally, the intrinsic coagulation cascade, activated by coagulation factor XII (FXII), has only recently been identified as another important mediator of thrombosis in cerebrovascular disease, thereby disproving established concepts. This review summarizes the latest insights into the pathophysiology of thrombus formation in the ischemic brain. Potential clinical merits of novel platelet inhibitors and anticoagulants as powerful and safe tools to combat ischemic stroke are discussed. KW - von Willebrand factor KW - platelets KW - glycoprotein Ib KW - FXII KW - coagulation KW - Stim Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126538 VL - 32 IS - 10 ER - TY - JOUR A1 - Kleinert, Stefan A1 - Tony, Hans-Peter A1 - Krause, Andreas A1 - Feuchtenberger, Martin A1 - Wassenberg, Siegfried A1 - Richter, Constanze A1 - Röther, Ekkehard A1 - Spieler, Wolfgang A1 - Gnann, Holger A1 - Wittig, Bianca M. T1 - Impact of patient and disease characteristics on therapeutic success during adalimumab treatment of patients with rheumatoid arthritis: data from a German JF - Rheumatology International N2 - The objective of this study was to use data from a noninterventional study to evaluate the effectiveness of adalimumab in rheumatoid arthritis (RA) patients during routine clinical practice and to explore the potential impact of patient and disease characteristics in response to adalimumab therapy. A total of 2,625 RA patients with specified data at baseline (prior to initiating adalimumab treatment) and 12 months entered this study between April 2003 and March 2009. We evaluated response to adalimumab therapy and conducted stepwise regression and subgroup analyses of factors influencing therapeutic response. During the 1-year adalimumab treatment period, disease activity decreased from a baseline mean disease activity score-28 joints (DAS28) of 5.9–3.9, while functional capacity improved from 59.0 to 68.4 Funktionsfragebogen Hannover (FFbH) percentage points. In multivariate regression models, high baseline DAS28 was the strongest positive predictor for decrease in disease activity, and high baseline functional capacity was associated with reduced gains in functional capacity. Male gender was a positive predictor of therapeutic response for both disease activity and functional capacity, while older age and multiple previous biologics were associated with a reduced therapeutic response. Subset analyses provided further support for the impact of baseline DAS28, FFbH, and prior biologic therapy on therapeutic response during treatment. We conclude that treatment with adalimumab leads to decreased disease activity and improved function during routine clinical practice. Patients with high disease activity and low functional capacity are particularly benefitted by adalimumab therapy. KW - antirheumatic agents KW - adalimumab KW - rheumatoid arthritis KW - treatment outcome KW - regression analysis Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126220 VL - 32 IS - 9 ER - TY - JOUR A1 - Becker, Jürgen C. A1 - Andersen, Mads H. A1 - Hofmeister-Müller, Valeska A1 - Wobser, Marion A1 - Frey, Lidia A1 - Sandig, Christiane A1 - Walter, Steffen A1 - Singh-Jasuja, Harpreet A1 - Kämpgen, Eckhart A1 - Opitz, Andreas A1 - Zapatka, Marc A1 - Bröcker, Eva-B. A1 - thor Straten, Per A1 - Schrama, David A1 - Ugurel, Selma T1 - Survivin-specific T-cell reactivity correlates with tumor response and patient survival: a phase-II peptide vaccination trial in metastatic melanoma JF - Cancer Immunology, Immunotherapy N2 - Background Therapeutic vaccination directed to induce an anti-tumoral T-cell response is a field of extensive investigation in the treatment of melanoma. However, many vaccination trials in melanoma failed to demonstrate a correlation between the vaccine-specific immune response and therapy outcome. This has been mainly attributed to immune escape by antigen loss, rendering us in the need of new vaccination targets. Patients and methods This phase-II trial investigated a peptide vaccination against survivin, an oncogenic inhibitor-of-apoptosis protein crucial for the survival of tumor cells, in HLA-A1/-A2/-B35-positive patients with treatment-refractory stage-IV metastatic melanoma. The study endpoints were survivin-specific T-cell reactivity (SSTR), safety, response, and survival (OS). Results Sixty-one patients (ITT) received vaccination therapy using three different regimens. 55 patients (PP) were evaluable for response and survival, and 41/55 for SSTR. Patients achieving progression arrest (CR + PR + SD) more often showed SSTRs than patients with disease progression (p = 0.0008). Patients presenting SSTRs revealed a prolonged OS (median 19.6 vs. 8.6 months; p = 0.0077); multivariate analysis demonstrated SSTR as an independent predictor of survival (p = 0.013). The induction of SSTRs was associated with gender (female vs. male; p = 0.014) and disease stage (M1a/b vs. M1c; p = 0.010), but not with patient age, HLA type, performance status, or vaccination regimen. Conclusion Survivin-specific T-cell reactivities strongly correlate with tumor response and patient survival, indicating that vaccination with survivin-derived peptides is a promising treatment strategy in melanoma. KW - peptide vaccination KW - therapy KW - survivin T-cell reactivity KW - melanoma Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126215 VL - 61 IS - 11 ER - TY - JOUR A1 - Bandyra, Katarzyna J. A1 - Said, Nelly A1 - Pfeiffer, Verena A1 - Górna, Maria W. A1 - Vogel, Jörg A1 - Luisi, Ben F. T1 - The Seed Region of a Small RNA Drives the Controlled Destruction of the Target mRNA by the Endoribonuclease RNase E JF - Molecular Cell N2 - Numerous small non-coding RNAs (sRNAs) in bacteria modulate rates of translation initiation and degradation of target mRNAs, which they recognize through base-pairing facilitated by the RNA chaperone Hfq. Recent evidence indicates that the ternary complex of Hfq, sRNA and mRNA guides endoribonuclease RNase E to initiate turnover of both the RNAs. We show that a sRNA not only guides RNase E to a defined site in a target RNA, but also allosterically activates the enzyme by presenting a monophosphate group at the 5′-end of the cognate-pairing “seed.” Moreover, in the absence of the target the 5′-monophosphate makes the sRNA seed region vulnerable to an attack by RNase E against which Hfq confers no protection. These results suggest that the chemical signature and pairing status of the sRNA seed region may help to both ‘proofread’ recognition and activate mRNA cleavage, as part of a dynamic process involving cooperation of RNA, Hfq and RNase E. KW - medicine Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126202 VL - 47 IS - 6 ER - TY - JOUR A1 - Parker, H. E. A1 - Adriaenssens, A. A1 - Rogers, G. A1 - Richards, P. A1 - Koepsell, H. A1 - Reimann, F. A1 - Gribble, F. M. T1 - Predominant role of active versus facilitative glucose transport for glucagon-like peptide-1 secretion JF - Diabetologia N2 - Aims/hypothesis Several glucose-sensing pathways have been implicated in glucose-triggered secretion of glucagon-like peptide-1 (GLP-1) from intestinal L cells. One involves glucose metabolism and closure of ATP-sensitive K\(^+\) channels, and another exploits the electrogenic nature of Na\(^+\)-coupled glucose transporters (SGLTs). This study aimed to elucidate the role of these distinct mechanisms in glucose-stimulated GLP-1 secretion. Methods Glucose uptake into L cells (either GLUTag cells or cells in primary cultures, using a new transgenic mouse model combining proglucagon promoter-driven Cre recombinase with a ROSA26tdRFP reporter) was monitored with the FLII\(_{12}\)Pglu-700μδ6 glucose sensor. Effects of pharmacological and genetic interference with SGLT1 or facilitative glucose transport (GLUT) on intracellular glucose accumulation and metabolism (measured by NAD(P)H autofluorescence), cytosolic Ca\(^{2+}\) (monitored with Fura2) and GLP-1 secretion (assayed by ELISA) were assessed. Results L cell glucose uptake was dominated by GLUT-mediated transport, being abolished by phloretin but not phloridzin. NAD(P)H autofluorescence was glucose dependent and enhanced by a glucokinase activator. In GLUTag cells, but not primary L cells, phloretin partially impaired glucose-dependent secretion, and suppressed an amplifying effect of glucose under depolarising high K\(^+\) conditions. The key importance of SGLT1 in GLUTag and primary cells was evident from the impairment of secretion by phloridzin or Sglt1 knockdown and failure of glucose to trigger cytosolic Ca\(^{2+}\) elevation in primary L cells from Sglt1 knockout mice. Conclusions/interpretation SGLT1 acts as the luminal glucose sensor in L cells, but intracellular glucose concentrations are largely determined by GLUT activity. Although L cell glucose metabolism depends partially on glucokinase activity, this plays only a minor role in glucose-stimulated GLP-1 secretion. KW - KATP channel KW - glucokinase KW - glucagon-like peptide-1 (GLP-1) KW - SGLT1 KW - L cells Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125927 VL - 55 IS - 9 ER - TY - JOUR A1 - Hansmann, Tamara A1 - Pliushch, Galyna A1 - Leubner, Monika A1 - Kroll, Patricia A1 - Endt, Daniela A1 - Gehrig, Andrea A1 - Preisler-Adams, Sabine A1 - Wieacker, Peter A1 - Haaf, Thomas T1 - Constitutive promoter methylation of BRCA1 and RAD51C in patients with familial ovarian cancer and early-onset sporadic breast cancer JF - Human Molecular Genetics N2 - Genetic defects in breast cancer (BC) susceptibility genes, most importantly BRCA1 and BRCA2, account for ∼40% of hereditary BC and ovarian cancer (OC). Little is known about the contribution of constitutive (soma-wide) epimutations to the remaining cases. We developed bisulfite pyrosequencing assays to screen >600 affected BRCA1/BRCA2 mutation-negative patients from the German Consortium for Hereditary Breast and Ovarian Cancer for constitutive hypermethylation of ATM, BRCA1, BRCA2, RAD51C, PTEN and TP53 in blood cells. In a second step, patients with ≥6% promoter methylation were analyzed by bisulfite plasmid sequencing to demonstrate the presence of hypermethylated alleles (epimutations), indicative of epigenetic gene silencing. Altogether we identified nine (1.4%) patients with constitutive BRCA1 and three (0.5%) with RAD51C hypermethylation. Epimutations were found in both sporadic cases, in particular in 2 (5.5%) of 37 patients with early-onset BC, and familial cases, in particular 4 (10%) of 39 patients with OC. Hypermethylation was always confined to one of the two parental alleles in a subset (12–40%) of the analyzed cells. Because epimutations occurred in cell types from different embryonal layers, they most likely originated in single cells during early somatic development. We propose that analogous to germline genetic mutations constitutive epimutations may serve as the first hit of tumor development. Because the role of constitutive epimutations in cancer development is likely to be largely underestimated, future strategies for effective testing of susceptibility to BC and OC should include an epimutation screen. KW - promoter methylation Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125673 VL - 21 IS - 21 ER - TY - JOUR A1 - Jaschke, Alexander A1 - Chung, Bomee A1 - Hesse, Deike A1 - Kluge, Reinhart A1 - Zahn, Claudia A1 - Moser, Markus A1 - Petzke, Klaus-Jürgen A1 - Brigelius-Flohé, Regina A1 - Puchkov, Dmytro A1 - Koepsell, Hermann A1 - Heeren, Joerg A1 - Joost, Hans-Georg A1 - Schürmann, Annette T1 - The GTPase ARFRP1 controls the lipidation of chylomicrons in the Golgi of the intestinal epithelium JF - Human Molecular Genetics N2 - The uptake and processing of dietary lipids by the small intestine is a multistep process that involves several steps including vesicular and protein transport. The GTPase ADP-ribosylation factor-related protein 1 (ARFRP1) controls the ARF-like 1 (ARL1)-mediated Golgi recruitment of GRIP domain proteins which in turn bind several Rab-GTPases. Here, we describe the essential role of ARFRP1 and its interaction with Rab2 in the assembly and lipidation of chylomicrons in the intestinal epithelium. Mice lacking Arfrp1 specifically in the intestine \((Arfrp1^{vil−/−})\) exhibit an early post-natal growth retardation with reduced plasma triacylglycerol and free fatty acid concentrations. \(Arfrp1^{vil−/−}\) enterocytes as well as Arfrp1 mRNA depleted Caco-2 cells absorbed fatty acids normally but secreted chylomicrons with a markedly reduced triacylglycerol content. In addition, the release of apolipoprotein A-I (ApoA-I) was dramatically decreased, and ApoA-I accumulated in the \(Arfrp1^{vil−/−}\) epithelium, where it predominantly co-localized with Rab2. The release of chylomicrons from Caco-2 was markedly reduced after the suppression of Rab2, ARL1 and Golgin-245. Thus, the GTPase ARFRP1 and its downstream proteins are required for the lipidation of chylo­microns and the assembly of ApoA-I to these particles in the Golgi of intestinal epithelial cells. KW - ARF Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125658 VL - 21 IS - 14 ER - TY - JOUR A1 - Maiden, Martin C. J. A1 - Frosch, Matthias T1 - Can we, should we, eradicate the meningococcus? JF - Vaccine N2 - The eradication of infectious agents is an attractive means of disease control that, to date, has been achieved for only one human pathogen, the smallpox virus. The introduction of vaccines against Neisseria meningitidis into immunisation schedules, and particularly the conjugate polysaccharide vaccines which can interrupt transmission, raises the question of whether disease caused by this obligate human bacterium can be controlled, eliminated, or even eradicated. The limited number of meningococcal serogroups, lack of an animal reservoir, and importance of meningococcal disease are considerations in favour of eradication; however, the commensal nature of most infections, the high diversity of meningococcal populations, and the lack of comprehensive vaccines are all factors that suggest that this is not feasible. Indeed, any such attempt might be harmful by perturbing the human microbiome and its interaction with the immune system. On balance, the control and possible elimination of disease caused by particular disease-associated meningococcal genotypes is a more achievable and worthwhile goal. KW - population biology KW - epidemiology KW - vaccines KW - neisseria meningitidis Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125646 VL - 30 IS - Suppl. 2 ER - TY - JOUR A1 - Nordbeck, Peter A1 - Beer, Meinrad A1 - Köstler, Herbert A1 - Ladd, Mark E. A1 - Quick, Harald H. A1 - Bauer, Wolfgang R. A1 - Ritter, Oliver T1 - Cardiac catheter ablation under real-time magnetic resonance guidance JF - European Heart Journal N2 - One of the main shortcomings of interventional electrophysiology (EP) is its inability to generate sufficient soft tissue contrast for intra-procedural visualization of the myocardium and the surrounding tissue, using conventional imaging techniques. Interventional cardiovascular magnetic resonance imaging (MRI) aims at bringing about significant improvements to the complex and decisive EP interventions far beyond the capabilities of currently available supportive imaging techniques used to surmount the drawbacks of fluoroscopy, as MRI not only allows of precise three-dimensional exposure of the cardiovascular morphology, but also proves to be a promising technique exclusively suitable for direct visualization of arrhythmogenic substrate and therapeutic effects. The major challenge posed by clinical … KW - magnetic resonance Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125638 VL - 33 IS - 15 ER - TY - JOUR A1 - Horn, Michael A1 - Baumann, Reto A1 - Pereira, Jorge A. A1 - Sidiropoulos, Páris N. M. A1 - Somandin, Christian A1 - Welzl, Hans A1 - Stendel, Claudia A1 - Lühmann, Tessa A1 - Wessig, Carsten A1 - Toyka, Klaus V. A1 - Relvas, João B. A1 - Senderek, Jan A1 - Suter, Ueli T1 - Myelin is dependent on the Charcot–Marie–Tooth Type 4H disease culprit protein FRABIN/FGD4 in Schwann cells JF - Brain N2 - Studying the function and malfunction of genes and proteins associated with inherited forms of peripheral neuropathies has provided multiple clues to our understanding of myelinated nerves in health and disease. Here, we have generated a mouse model for the peripheral neuropathy Charcot–Marie–Tooth disease type 4H by constitutively disrupting the mouse orthologue of the suspected culprit gene FGD4 that encodes the small RhoGTPase Cdc42-guanine nucleotide exchange factor Frabin. Lack of Frabin/Fgd4 causes dysmyelination in mice in early peripheral nerve development, followed by profound myelin abnormalities and demyelination at later stages. At the age of 60 weeks, this was accompanied by electrophysiological deficits. By crossing mice carrying alleles of Frabin/Fgd4 flanked by loxP sequences with animals expressing Cre recombinase in a cell type-specific manner, we show that Schwann cell-autonomous Frabin/Fgd4 function is essential for proper myelination without detectable primary contributions from neurons. Deletion of Frabin/Fgd4 in Schwann cells of fully myelinated nerve fibres revealed that this protein is not only required for correct nerve development but also for accurate myelin maintenance. Moreover, we established that correct activation of Cdc42 is dependent on Frabin/Fgd4 function in healthy peripheral nerves. Genetic disruption of Cdc42 in Schwann cells of adult myelinated nerves resulted in myelin alterations similar to those observed in Frabin/Fgd4-deficient mice, indicating that Cdc42 and the Frabin/Fgd4–Cdc42 axis are critical for myelin homeostasis. In line with known regulatory roles of Cdc42, we found that Frabin/Fgd4 regulates Schwann cell endocytosis, a process that is increasingly recognized as a relevant mechanism in peripheral nerve pathophysiology. Taken together, our results indicate that regulation of Cdc42 by Frabin/Fgd4 in Schwann cells is critical for the structure and function of the peripheral nervous system. In particular, this regulatory link is continuously required in adult fully myelinated nerve fibres. Thus, mechanisms regulated by Frabin/Fgd4–Cdc42 are promising targets that can help to identify additional regulators of myelin development and homeostasis, which may crucially contribute also to malfunctions in different types of peripheral neuropathies. KW - Frabin/Fgd4 KW - myelination KW - hereditary motor and sensory neuropathy KW - Charcot–Marie–Tooth disease KW - Rho-GTPase Cdc42 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125390 VL - 135 ER - TY - JOUR A1 - Galetzka, Danuta A1 - Hansmann, Tamara A1 - El Hajj, Nady A1 - Weis, Eva A1 - Irmscher, Benjamin A1 - Ludwig, Marco A1 - Schneider-Rätzke, Brigitte A1 - Kohlschmidt, Nicolai A1 - Beyer, Vera A1 - Bartsch, Oliver A1 - Zechner, Ulrich A1 - Spix, Claudia A1 - Haaf, Thomas T1 - Monozygotic twins discordant for constitutive BRCA1 promoter methylation, childhood cancer and secondary cancer JF - Epigenetics N2 - We describe monozygotic twins discordant for childhood leukemia and secondary thyroid carcinoma. We used bisulfite pyrosequencing to compare the constitutive promoter methylation of BRCA1 and several other tumor suppressor genes in primary fibroblasts. The affected twin displayed an increased BRCA1 methylation (12%), compared with her sister (3%). Subsequent bisulfite plasmid sequencing demonstrated that 13% (6 of 47) BRCA1 alleles were fully methylated in the affected twin, whereas her sister displayed only single CpG errors without functional implications. This between-twin methylation difference was also found in irradiated fibroblasts and untreated saliva cells. The BRCA1 epimutation may have originated by an early somatic event in the affected twin: approximately 25% of her body cells derived from different embryonic cell lineages carry one epigenetically inactivated BRCA1 allele. This epimutation was associated with reduced basal protein levels and a higher induction of BRCA1 after DNA damage. In addition, we performed a genome-wide microarray analysis of both sisters and found several copy number variations, i.e., heterozygous deletion and reduced expression of the RSPO3 gene in the affected twin. This monozygotic twin pair represents an impressive example of epigenetic somatic mosaicism, suggesting a role for constitutive epimutations, maybe along with de novo genetic alterations in recurrent tumor development. KW - BRCA1 KW - childhood cancer KW - DNA Methylation KW - epimutation KW - monozygotic twins KW - secondary cancer KW - somatic mosaicism Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125386 VL - 7 IS - 1 ER - TY - JOUR A1 - Gerlach, Manfred A1 - Maetzler, Walter A1 - Broich, Karl A1 - Hampel, Harald A1 - Rems, Lucas A1 - Reum, Torsten A1 - Riederer, Peter A1 - Stäffler, Albrecht A1 - Streffer, Johannes A1 - Berg, Daniela T1 - Biomarker candidates of neurodegeneration in Parkinson's disease for the evaluation of disease-modifying therapeutics JF - Journal of Neural Transmission N2 - Reliable biomarkers that can be used for early diagnosis and tracking disease progression are the cornerstone of the development of disease-modifying treatments for Parkinson’s disease (PD). The German Society of Experimental and Clinical Neurotherapeutics (GESENT) has convened a Working Group to review the current status of proposed biomarkers of neurodegeneration according to the following criteria and to develop a consensus statement on biomarker candidates for evaluation of disease-modifying therapeutics in PD. The criteria proposed are that the biomarker should be linked to fundamental features of PD neuropathology and mechanisms underlying neurodegeneration in PD, should be correlated to disease progression assessed by clinical rating scales, should monitor the actual disease status, should be pre-clinically validated, and confirmed by at least two independent studies conducted by qualified investigators with the results published in peer-reviewed journals. To date, available data have not yet revealed one reliable biomarker to detect early neurodegeneration in PD and to detect and monitor effects of drug candidates on the disease process, but some promising biomarker candidates, such as antibodies against neuromelanin, pathological forms of α-synuclein, DJ-1, and patterns of gene expression, metabolomic and protein profiling exist. Almost all of the biomarker candidates were not investigated in relation to effects of treatment, validated in experimental models of PD and confirmed in independent studies. KW - disease progression KW - biomarkers KW - neuroprotection KW - disease-modifying therapies KW - Parkinson’s disease KW - surrogate endpoints KW - drug development Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125375 VL - 119 IS - 1 ER - TY - JOUR A1 - Jain, M. A1 - Vélez, J. I. A1 - Acosta, M. T. A1 - Palacio, L. G. A1 - Balog, J. A1 - Roessler, E. A1 - Pineda, D. A1 - Londoño, A. C. A1 - Palacio, J. D. A1 - Arbelaez, A. A1 - Lopera, F. A1 - Elia, J. A1 - Hakonarson, H. A1 - Seitz, C. A1 - Freitag, C. M. A1 - Palmason, H. A1 - Meyer, J. A1 - Romanos, M. A1 - Walitza, S. A1 - Hemminger, U. A1 - Warnke, A. A1 - Romanos, J. A1 - Renner, T. A1 - Jacob, C. A1 - Lesch, K.-P. A1 - Swanson, J. A1 - Castellanos, F. X. A1 - Bailey-Wilson, J. E. A1 - Arcos-Burgos, M. A1 - Muenke, M. T1 - A cooperative interaction between LPHN3 and 11q doubles the risk for ADHD JF - Molecular Psychiatry N2 - In previous studies of a genetic isolate, we identified significant linkage of attention deficit hyperactivity disorder (ADHD) to 4q, 5q, 8q, 11q and 17p. The existence of unique large size families linked to multiple regions, and the fact that these families came from an isolated population, we hypothesized that two-locus interaction contributions to ADHD were plausible. Several analytical models converged to show significant interaction between 4q and 11q (P<1 × 10−8) and 11q and 17p (P<1 × 10−6). As we have identified that common variants of the LPHN3 gene were responsible for the 4q linkage signal, we focused on 4q–11q interaction to determine that single-nucleotide polymorphisms (SNPs) harbored in the LPHN3 gene interact with SNPs spanning the 11q region that contains DRD2 and NCAM1 genes, to double the risk of developing ADHD. This interaction not only explains genetic effects much better than taking each of these loci effects by separated but also differences in brain metabolism as depicted by proton magnetic resonance spectroscopy data and pharmacogenetic response to stimulant medication. These findings not only add information about how high order genetic interactions might be implicated in conferring susceptibility to develop ADHD but also show that future studies of the effects of genetic interactions on ADHD clinical information will help to shape predictive models of individual outcome. KW - ADHD KW - genetic interaction KW - LPHN3 KW - NCAM1 KW - DRD2 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125128 VL - 17 ER -