Publications

251 Publications visible to you, out of a total of 251

Abstract (Expand)

Objective Human blood metabolites are influenced by a number of lifestyle and environmental factors. Identification of these factors and the proper quantification of their relevance provides insightss into human biological and metabolic disease processes, is key for standardized translation of metabolite biomarkers into clinical applications, and is a prerequisite for comparability of data between studies. However, so far only limited data exist from large and well-phenotyped human cohorts and current methods for analysis do not fully account for the characteristics of these data. The primary aim of this study was to identify, quantify and compare the impact of a comprehensive set of clinical and lifestyle related factors on metabolite levels in three large human cohorts. To achieve this goal, we improve current methodology by developing a principled analysis approach, which could be translated to other cohorts and metabolite panels. Methods 63 Metabolites (amino acids, acylcarnitines) were quantified by liquid chromatography tandem mass spectrometry in three cohorts (total N~=~16,222). Supported by a simulation study evaluating various analytical approaches, we developed an analysis pipeline including preprocessing, identification, and quantification of factors affecting metabolite levels. We comprehensively identified uni- and multivariable metabolite associations considering 29 environmental and clinical factors and performed metabolic pathway enrichment and network analyses. Results Inverse normal transformation of batch corrected and outlier removed metabolite levels accompanied by linear regression analysis proved to be the best suited method to deal with the metabolite data. Association analyses revealed numerous uni- and multivariable significant associations. 15 of the analyzed 29 factors explained {\textgreater}1{\%} of variance for at least one of the metabolites. Strongest factors are application of steroid hormones, reticulocytes, waist-to-hip ratio, sex, haematocrit, and age. Effect sizes of factors are comparable across studies. Conclusions We introduced a principled approach for the analysis of MS data allowing identification, and quantification of effects of clinical and lifestyle factors with metabolite levels. We detected a number of known and novel associations broadening our understanding of the regulation of the human metabolome. The large heterogeneity observed between cohorts could almost completely be explained by differences in the distribution of influencing factors emphasizing the necessity of a proper confounder analysis when interpreting metabolite associations.

Authors: Carl Beuchel, Susen Becker, Julia Dittrich, Holger Kirsten, Anke Toenjes, Michael Stumvoll, Markus Loeffler, Holger Thiele, Frank Beutner, Joachim Thiery, Uta Ceglarek, Markus Scholz

Date Published: 17th Aug 2019

Publication Type: Not specified

Abstract (Expand)

Since Drosophila melanogaster has proven to be a useful model system to study phenotypes of oncogenic mutations and to identify new anti-cancer drugs, we generated human BRAFV600E homologous dRaf mutant (dRaf A572E ) Drosophila melanogaster strains to use these for characterization of mutant phenotypes and exploit these phenotypes for drug testing. For mutant gene expression, the GAL4/UAS expression system was used. dRaf A572E was expressed tissue-specific in the eye, epidermis, heart, wings, secretory glands and in the whole animal. Expression of dRaf A572E under the control of an eye-specific driver led to semi-lethality and a rough eye phenotype. tumor, genetics, molecular biology, BRAF, small molecule inhibitors The vast majority of other tissue-specific and ubiquitous drivers led to a lethal phenotype only. The rough eye phenotype was used to test BRAF inhibitor vemurafenib and MEK1/2 inhibitor cobimetinib. There was no phenotype rescue by this treatment. However, a significant rescue of the lethal phenotype was observed under a gut-specific driver. Here, MEK1/2 inhibitor cobimetinib rescued Drosophila larvae to reach pupal stage in 37% of cases as compared to 1% in control experiments. Taken together, the BRAFV600E homolog dRaf A572E exerts mostly lethal effects in Drosophila. Gut-specific dRaf A572E expression might in future be developed further for drug testing. This article is protected by copyright. All rights reserved.

Authors: Isabelle Pfeifle, Jens Bohnekamp, Anna Volkhardt, Holger Kirsten, Astrid Rohwedder, Andreas Thum, Thomas M. Magin, Manfred Kunz

Date Published: 1st Aug 2019

Publication Type: Journal article

Abstract (Expand)

The central neurocytoma (CN) is a rare brain tumor with a frequency of 0.1-0.5% of all brain tumors. According to the World Health Organization classification, it is a benign grade II tumor with good prognosis. However, some CN occur as histologically \textquotedblatypical\textquotedbl variant, combined with increasing proliferation and poor clinical outcome. Detailed genetic knowledge could be helpful to characterize a potential atypical behavior in CN. Only few publications on genetics of CN exist in the literature. Therefore, we performed cytogenetic analysis of an intraventricular neurocytoma WHO grade II in a 39-year-old male patient by use of genome-wide high-density single nucleotide polymorphism array (SNP array) and subtelomere FISH. Applying these techniques, we could detect known chromosomal aberrations and identified six not previously described chromosomal aberrations, gains of 1p36.33-p36.31, 2q37.1-q37.3, 6q27, 12p13.33-p13.31, 20q13.31-q13.33, and loss of 19p13.3-p12. Our case report contributes to the genetic knowledge about CN and to increased understanding of \textquotedbltypical\textquotedbl and \textquotedblatypical\textquotedbl variants.

Authors: Caroline Sander, Marco Wallenborn, Vivian Pascal Brandt, Peter Ahnert, Vera Reuschel, Christan Eisenlöffel, Wolfgang Krupp, Jürgen Meixensberger, Heidrun Holland

Date Published: 1st Jul 2019

Publication Type: Journal article

Abstract (Expand)

CONTEXT: Steroid hormones are important regulators of physiological processes in humans and are under genetic control. A link to coronary artery disease (CAD) is supposed. OBJECTIVE: Our main objectivee was to identify genetic loci influencing steroid hormone levels. As secondary aim, we searched for causal effects of steroid hormones on CAD. DESIGN: We conducted genome-wide meta-association studies for eight steroid hormones: cortisol, DHEA-S, estradiol and testosterone in two independent cohorts (LIFE-Adult, LIFE-Heart, max. n=7667), and progesterone, 17-hydroxyprogesterone, androstenedione and aldosterone in LIFE-Heart only (max. n=2070). All genome-wide significant loci were tested for sex interactions. Further, we tested if previously reported CAD SNPs were associated with our steroid hormone panel and investigated causal links between hormone levels and CAD status using Mendelian Randomization (MR) approaches. RESULTS: We discovered 15 novel associated loci for 17-hydroxyprogesterone, progesterone, DHEA-S, cortisol, androstenedione, and estradiol. Five of these loci relate to genes directly involved in steroid metabolism: CYP21A1, CYP11B1, CYP17A1, STS, and HSD17B12, almost completing the set of steroidogenic enzymes with genetic associations. Sexual dimorphisms were found for seven of the novel loci. Other loci correspond, e.g., to the WNT4/β-catenin pathway. MR revealed that cortisol, androstenedione, 17-hydroxyprogesterone and DHEA-S had causal effects on CAD. We also observed enrichment of cortisol and testosterone associations among known CAD hits. CONCLUSION: Our study greatly improves insight into genetic regulation of steroid hormones and their dependency on sex. These results could serve as a basis for analyzing sex-dimorphisms in other complex diseases.

Authors: J. Pott, YJ. Bae, K. Horn, A. Teren, Andreas Kühnapfel, H. Kirsten, U. Ceglarek, Markus Löffler, J. Thiery, J. Kratzsch, Markus Scholz

Date Published: 6th Jun 2019

Publication Type: Not specified

Human Diseases: coronary artery disease

Abstract (Expand)

Cardiovascular disease (CVD) remains the leading cause of death worldwide and, despite continuous advances, better diagnostic and prognostic tools, as well as therapy, are needed. The human transcriptome, which is the set of all RNA produced in a cell, is much more complex than previously thought and the lack of dialogue between researchers and industrials and consensus on guidelines to generate data make it harder to compare and reproduce results. This European Cooperation in Science and Technology (COST) Action aims to accelerate the understanding of transcriptomics in CVD and further the translation of experimental data into usable applications to improve personalized medicine in this field by creating an interdisciplinary network. It aims to provide opportunities for collaboration between stakeholders from complementary backgrounds, allowing the functions of different RNAs and their interactions to be more rapidly deciphered in the cardiovascular context for translation into the clinic, thus fostering personalized medicine and meeting a current public health challenge. Thus, this Action will advance studies on cardiovascular transcriptomics, generate innovative projects, and consolidate the leadership of European research groups in the field.COST (European Cooperation in Science and Technology) is a funding organization for research and innovation networks (www.cost.eu).

Authors: Clarissa Pedrosa da C. Gomes, Bence Ágg, Andrejaana Andova, Serdal Arslan, Andrew Baker, Monika Barteková, Dimitris Beis, Fay Betsou, Stephanie Bezzina Wettinger, Branko Bugarski, Gianluigi Condorelli, Gustavo José Justo da Silva, Sabrina Danilin, David de Gonzalo-Calvo, Alfonso Buil, Maria Carmo-Fonseca, Francisco J. Enguita, Kyriacos Felekkis, Peter Ferdinandy, Mariann Gyöngyösi, Matthias Hackl, Kanita Karaduzovic-Hadziabdic, Jan Hellemans, Stephane Heymans, Markéta Hlavackova, Morten Andre Hoydal, Aleksandra Jankovic, Amela Jusic, Dimitris Kardassis, Risto Kerkelä, Gabriela M. Kuster, Päivi Lakkisto, Przemyslaw Leszek, Mitja Lustrek, Lars Maegdefessel, Fabio Martelli, Susana Novella, Timothy O’Brien, Christos Papaneophytou, Thierry Pedrazzini, Florence Pinet, Octavian Popescu, Ines Potočnjak, Emma Robinson, Shlomo Sasson, Markus Scholz, Maya Simionescu, Monika Stoll, Zoltan V. Varga, Manlio Vinciguerra, Angela Xuereb, Mehmet Birhan Yilmaz, Costanza Emanueli, Yvan Devaux, behalf of the EU-CardioRNA COST Action on

Date Published: 1st Jun 2019

Publication Type: Journal article

Abstract (Expand)

Chronic kidney disease (CKD) is responsible for a public health burden with multi-systemic complications. Through trans-ancestry meta-analysis of genome-wide association studies of estimated glomerular filtration rate (eGFR) and independent replication (n = 1,046,070), we identified 264 associated loci (166 new). Of these, 147 were likely to be relevant for kidney function on the basis of associations with the alternative kidney function marker blood urea nitrogen (n = 416,178). Pathway and enrichment analyses, including mouse models with renal phenotypes, support the kidney as the main target organ. A genetic risk score for lower eGFR was associated with clinically diagnosed CKD in 452,264 independent individuals. Colocalization analyses of associations with eGFR among 783,978 European-ancestry individuals and gene expression across 46 human tissues, including tubulo-interstitial and glomerular kidney compartments, identified 17 genes differentially expressed in kidney. Fine-mapping highlighted missense driver variants in 11 genes and kidney-specific regulatory variants. These results provide a comprehensive priority list of molecular targets for translational research.

Authors: Matthias Wuttke, Yong Li, Man Li, Karsten B. Sieber, Mary F. Feitosa, Mathias Gorski, Adrienne Tin, Lihua Wang, Audrey Y. Chu, Anselm Hoppmann, Holger Kirsten, Ayush Giri, Jin-Fang Chai, Gardar Sveinbjornsson, Bamidele O. Tayo, Teresa Nutile, Christian Fuchsberger, Jonathan Marten, Massimiliano Cocca, Sahar Ghasemi, Yizhe Xu, Katrin Horn, Damia Noce, Peter J. van der Most, Sanaz Sedaghat, Zhi Yu, Masato Akiyama, Saima Afaq, Tarunveer S. Ahluwalia, Peter Almgren, Najaf Amin, Johan Ärnlöv, Stephan J. L. Bakker, Nisha Bansal, Daniela Baptista, Sven Bergmann, Mary L. Biggs, Ginevra Biino, Michael Boehnke, Eric Boerwinkle, Mathilde Boissel, Erwin P. Bottinger, Thibaud S. Boutin, Hermann Brenner, Marco Brumat, Ralph Burkhardt, Adam S. Butterworth, Eric Campana, Archie Campbell, Harry Campbell, Mickaël Canouil, Robert J. Carroll, Eulalia Catamo, John C. Chambers, Miao-Ling Chee, Miao-Li Chee, Xu Chen, Ching-Yu Cheng, Yurong Cheng, Kaare Christensen, Renata Cifkova, Marina Ciullo, Maria Pina Concas, James P. Cook, Josef Coresh, Tanguy Corre, Cinzia Felicita Sala, Daniele Cusi, John Danesh, E. Warwick Daw, Martin H. de Borst, Alessandro de Grandi, Renée de Mutsert, Aiko P. J. de Vries, Frauke Degenhardt, Graciela Delgado, Ayse Demirkan, Emanuele Di Angelantonio, Katalin Dittrich, Jasmin Divers, Rajkumar Dorajoo, Kai-Uwe Eckardt, Georg Ehret, Paul Elliott, Karlhans Endlich, Michele K. Evans, Janine F. Felix, Valencia Hui Xian Foo, Oscar H. Franco, Andre Franke, Barry I. Freedman, Sandra Freitag-Wolf, Yechiel Friedlander, Philippe Froguel, Ron T. Gansevoort, He Gao, Paolo Gasparini, J. Michael Gaziano, Vilmantas Giedraitis, Christian Gieger, Giorgia Girotto, Franco Giulianini, Martin Gögele, Scott D. Gordon, Daniel F. Gudbjartsson, Vilmundur Gudnason, Toomas Haller, Pavel Hamet, Tamara B. Harris, Catharina A. Hartman, Caroline Hayward, Jacklyn N. Hellwege, Chew-Kiat Heng, Andrew A. Hicks, Edith Hofer, Wei Huang, Nina Hutri-Kähönen, Shih-Jen Hwang, M. Arfan Ikram, Olafur S. Indridason, Erik Ingelsson, Marcus Ising, Vincent W. V. Jaddoe, Johanna Jakobsdottir, Jost B. Jonas, Peter K. Joshi, Navya Shilpa Josyula, Bettina Jung, Mika Kähönen, Yoichiro Kamatani, Candace M. Kammerer, Masahiro Kanai, Mika Kastarinen, Shona M. Kerr, Chiea-Chuen Khor, Wieland Kiess, Marcus E. Kleber, Wolfgang Koenig, Jaspal S. Kooner, Antje Körner, Peter Kovacs, Aldi T. Kraja, Alena Krajcoviechova, Holly Kramer, Bernhard K. Krämer, Florian Kronenberg, Michiaki Kubo, Brigitte Kühnel, Mikko Kuokkanen, Johanna Kuusisto, Martina La Bianca, Markku Laakso, Leslie A. Lange, Carl D. Langefeld, Jeannette Jen-Mai Lee, Benjamin Lehne, Terho Lehtimäki, Wolfgang Lieb, Su-Chi Lim, Lars Lind, Cecilia M. Lindgren, Jun Liu, Jianjun Liu, Markus Loeffler, Ruth J. F. Loos, Susanne Lucae, Mary Ann Lukas, Leo-Pekka Lyytikäinen, Reedik Mägi, Patrik K. E. Magnusson, Anubha Mahajan, Nicholas G. Martin, Jade Martins, Winfried März, Deborah Mascalzoni, Koichi Matsuda, Christa Meisinger, Thomas Meitinger, Olle Melander, Andres Metspalu, Evgenia K. Mikaelsdottir, Yuri Milaneschi, Kozeta Miliku, Pashupati P. Mishra, Karen L. Mohlke, Nina Mononen, Grant W. Montgomery, Dennis O. Mook-Kanamori, Josyf C. Mychaleckyj, Girish N. Nadkarni, Mike A. Nalls, Matthias Nauck, Kjell Nikus, Boting Ning, Ilja M. Nolte, Raymond Noordam, Jeffrey O’Connell, Michelle L. O’Donoghue, Isleifur Olafsson, Albertine J. Oldehinkel, Marju Orho-Melander, Willem H. Ouwehand, Sandosh Padmanabhan, Nicholette D. Palmer, Runolfur Palsson, Brenda W. J. H. Penninx, Thomas Perls, Markus Perola, Mario Pirastu, Nicola Pirastu, Giorgio Pistis, Anna I. Podgornaia, Ozren Polasek, Belen Ponte, David J. Porteous, Tanja Poulain, Peter P. Pramstaller, Michael H. Preuss, Bram P. Prins, Michael A. Province, Ton J. Rabelink, Laura M. Raffield, Olli T. Raitakari, Dermot F. Reilly, Rainer Rettig, Myriam Rheinberger, Kenneth M. Rice, Paul M. Ridker, Fernando Rivadeneira, Federica Rizzi, David J. Roberts, Antonietta Robino, Peter Rossing, Igor Rudan, Rico Rueedi, Daniela Ruggiero, Kathleen A. Ryan, Yasaman Saba, Charumathi Sabanayagam, Veikko Salomaa, Erika Salvi, Kai-Uwe Saum, Helena Schmidt, Reinhold Schmidt, Ben Schöttker, Christina-Alexandra Schulz, Nicole Schupf, Christian M. Shaffer, Yuan Shi, Albert V. Smith, Blair H. Smith, Nicole Soranzo, Cassandra N. Spracklen, Konstantin Strauch, Heather M. Stringham, Michael Stumvoll, Per O. Svensson, Silke Szymczak, E-Shyong Tai, Salman M. Tajuddin, Nicholas Y. Q. Tan, Kent D. Taylor, Andrej Teren, Yih-Chung Tham, Joachim Thiery, Chris H. L. Thio, Hauke Thomsen, Gudmar Thorleifsson, Daniela Toniolo, Anke Tönjes, Johanne Tremblay, Ioanna Tzoulaki, André G. Uitterlinden, Simona Vaccargiu, Rob M. van Dam, Pim van der Harst, Cornelia M. van Duijn, Digna R. Velez Edward, Niek Verweij, Suzanne Vogelezang, Uwe Völker, Peter Vollenweider, Gerard Waeber, Melanie Waldenberger, Lars Wallentin, Ya Xing Wang, Chaolong Wang, Dawn M. Waterworth, Wen Bin Wei, Harvey White, John B. Whitfield, Sarah H. Wild, James F. Wilson, Mary K. Wojczynski, Charlene Wong, Tien-Yin Wong, Liang Xu, Qiong Yang, Masayuki Yasuda, Laura M. Yerges-Armstrong, Weihua Zhang, Alan B. Zonderman, Jerome I. Rotter, Murielle Bochud, Bruce M. Psaty, Veronique Vitart, James G. Wilson, Abbas Dehghan, Afshin Parsa, Daniel I. Chasman, Kevin Ho, Andrew P. Morris, Olivier Devuyst, Shreeram Akilesh, Sarah A. Pendergrass, Xueling Sim, Carsten A. Böger, Yukinori Okada, Todd L. Edwards, Harold Snieder, Kari Stefansson, Adriana M. Hung, Iris M. Heid, Markus Scholz, Alexander Teumer, Anna Köttgen, Cristian Pattaro

Date Published: 1st Jun 2019

Publication Type: Journal article

Abstract (Expand)

OBJECTIVE: Margin analysis of Class III and IV composite restorations in vitro and in vivo occurred by scanning electron microscopy (SEM) and optical coherence tomography (OCT). The results were comparedd and related to clinical evaluation. METHODS AND MATERIALS: Eight Class III composite restorations were imaged in vitro using OCT and SEM. The margins were analyzed quantitatively. OCT signals were verified by assignment to the criteria perfect margin, gap, and positive/negative ledge. In vivo quantitative margin analysis of Class III/IV composite restorations made of the micro-hybrid composite Venus combined with the self-etch adhesive iBond Gluma inside (1-SE) or etch-and-rinse adhesive Gluma Comfort Bond (2-ER) (all Heraeus Kulzer) was carried out using OCT and SEM after 90 months of clinical function. The results were compared with clinical evaluation (US Public Health Service criteria; marginal integrity, marginal discoloration). RESULTS: In vitro, the correlation between OCT and SEM was high for all four margin criteria (Kendall tau b [\textgreektb] correlation: 0.64-0.92, pi\leq0.026), with no significant differences between OCT and SEM ( pi\geq0.63). In vivo, a moderate correlation was observed (\textgreektb: 0.38-0.45, pi\textless0.016). Clinically, the cumulative failure rate in the criterion marginal integrity was higher for the 1-SE group (baseline 90 M, p=0.011). Similarly, OCT and SEM detected higher percentages of the criterion gap in the 1-SE group ( p: 0.027/0.002), in contrast to perfect margin. Both, gap and perfect margin ranged widely between 0.0% and 88.7% (OCT) and between 0.0% and 89.0% (SEM). CONCLUSION: Despite the positive selection bias after 90 months with only a few patients left, quantitative margin analysis allows for differentiation between the two adhesives at this specific date. OCT in particular offers the possibility to evaluate marginal integrity directly in vivo.

Authors: H. Schneider, A. S. Steigerwald-Otremba, M. Häfer, F. Krause, M. Scholz, R. Haak

Date Published: 1st May 2019

Publication Type: Journal article

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