@article{AhmedZeeshanDandekar2016, author = {Ahmed, Zeeshan and Zeeshan, Saman and Dandekar, Thomas}, title = {Mining biomedical images towards valuable information retrieval in biomedical and life sciences}, series = {Database - The Journal of Biological Databases and Curation}, volume = {2016}, journal = {Database - The Journal of Biological Databases and Curation}, doi = {10.1093/database/baw118}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162697}, pages = {baw118}, year = {2016}, abstract = {Biomedical images are helpful sources for the scientists and practitioners in drawing significant hypotheses, exemplifying approaches and describing experimental results in published biomedical literature. In last decades, there has been an enormous increase in the amount of heterogeneous biomedical image production and publication, which results in a need for bioimaging platforms for feature extraction and analysis of text and content in biomedical images to take advantage in implementing effective information retrieval systems. In this review, we summarize technologies related to data mining of figures. We describe and compare the potential of different approaches in terms of their developmental aspects, used methodologies, produced results, achieved accuracies and limitations. Our comparative conclusions include current challenges for bioimaging software with selective image mining, embedded text extraction and processing of complex natural language queries.}, language = {en} } @article{HanRenMamtiminetal.2023, author = {Han, Chao and Ren, Pengxuan and Mamtimin, Medina and Kruk, Linus and Sarukhanyan, Edita and Li, Chenyu and Anders, Hans-Joachim and Dandekar, Thomas and Krueger, Irena and Elvers, Margitta and Goebel, Silvia and Adler, Kristin and M{\"u}nch, G{\"o}tz and Gudermann, Thomas and Braun, Attila and Mammadova-Bach, Elmina}, title = {Minimal collagen-binding epitope of glycoprotein VI in human and mouse platelets}, series = {Biomedicines}, volume = {11}, journal = {Biomedicines}, number = {2}, issn = {2227-9059}, doi = {10.3390/biomedicines11020423}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304148}, year = {2023}, abstract = {Glycoprotein VI (GPVI) is a platelet-specific receptor for collagen and fibrin, regulating important platelet functions such as platelet adhesion and thrombus growth. Although the blockade of GPVI function is widely recognized as a potent anti-thrombotic approach, there are limited studies focused on site-specific targeting of GPVI. Using computational modeling and bioinformatics, we analyzed collagen- and CRP-binding surfaces of GPVI monomers and dimers, and compared the interacting surfaces with other mammalian GPVI isoforms. We could predict a minimal collagen-binding epitope of GPVI dimer and designed an EA-20 antibody that recognizes a linear epitope of this surface. Using platelets and whole blood samples donated from wild-type and humanized GPVI transgenic mice and also humans, our experimental results show that the EA-20 antibody inhibits platelet adhesion and aggregation in response to collagen and CRP, but not to fibrin. The EA-20 antibody also prevents thrombus formation in whole blood, on the collagen-coated surface, in arterial flow conditions. We also show that EA-20 does not influence GPVI clustering or receptor shedding. Therefore, we propose that blockade of this minimal collagen-binding epitope of GPVI with the EA-20 antibody could represent a new anti-thrombotic approach by inhibiting specific interactions between GPVI and the collagen matrix.}, language = {en} } @article{KunzGoettlichWallesetal.2017, author = {Kunz, Meik and G{\"o}ttlich, Claudia and Walles, Thorsten and Nietzer, Sarah and Dandekar, Gudrun and Dandekar, Thomas}, title = {MicroRNA-21 versus microRNA-34: Lung cancer promoting and inhibitory microRNAs analysed in silico and in vitro and their clinical impact}, series = {Tumor Biology}, volume = {39}, journal = {Tumor Biology}, number = {7}, doi = {10.1177/1010428317706430}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158399}, year = {2017}, abstract = {MicroRNAs are well-known strong RNA regulators modulating whole functional units in complex signaling networks. Regarding clinical application, they have potential as biomarkers for prognosis, diagnosis, and therapy. In this review, we focus on two microRNAs centrally involved in lung cancer progression. MicroRNA-21 promotes and microRNA-34 inhibits cancer progression. We elucidate here involved pathways and imbed these antagonistic microRNAs in a network of interactions, stressing their cancer microRNA biology, followed by experimental and bioinformatics analysis of such microRNAs and their targets. This background is then illuminated from a clinical perspective on microRNA-21 and microRNA-34 as general examples for the complex microRNA biology in lung cancer and its diagnostic value. Moreover, we discuss the immense potential that microRNAs such as microRNA-21 and microRNA-34 imply by their broad regulatory effects. These should be explored for novel therapeutic strategies in the clinic.}, language = {en} } @article{CaliskanDangwalDandekar2023, author = {Caliskan, Aylin and Dangwal, Seema and Dandekar, Thomas}, title = {Metadata integrity in bioinformatics: bridging the gap between data and knowledge}, series = {Computational and Structural Biotechnology Journal}, volume = {21}, journal = {Computational and Structural Biotechnology Journal}, issn = {2001-0370}, doi = {10.1016/j.csbj.2023.10.006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-349990}, pages = {4895-4913}, year = {2023}, abstract = {In the fast-evolving landscape of biomedical research, the emergence of big data has presented researchers with extraordinary opportunities to explore biological complexities. In biomedical research, big data imply also a big responsibility. This is not only due to genomics data being sensitive information but also due to genomics data being shared and re-analysed among the scientific community. This saves valuable resources and can even help to find new insights in silico. To fully use these opportunities, detailed and correct metadata are imperative. This includes not only the availability of metadata but also their correctness. Metadata integrity serves as a fundamental determinant of research credibility, supporting the reliability and reproducibility of data-driven findings. Ensuring metadata availability, curation, and accuracy are therefore essential for bioinformatic research. Not only must metadata be readily available, but they must also be meticulously curated and ideally error-free. Motivated by an accidental discovery of a critical metadata error in patient data published in two high-impact journals, we aim to raise awareness for the need of correct, complete, and curated metadata. We describe how the metadata error was found, addressed, and present examples for metadata-related challenges in omics research, along with supporting measures, including tools for checking metadata and software to facilitate various steps from data analysis to published research. Highlights • Data awareness and data integrity underpins the trustworthiness of results and subsequent further analysis. • Big data and bioinformatics enable efficient resource use by repurposing publicly available RNA-Sequencing data. • Manual checks of data quality and integrity are insufficient due to the overwhelming volume and rapidly growing data. • Automation and artificial intelligence provide cost-effective and efficient solutions for data integrity and quality checks. • FAIR data management, various software solutions and analysis tools assist metadata maintenance.}, language = {en} } @article{ShityakovDandekar2010, author = {Shityakov, Sergey and Dandekar, Thomas}, title = {Lead expansion and virtual screening of Indinavir derivate HIV-1 protease inhibitors using pharmacophoric - shape similarity scoring function}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-67824}, year = {2010}, abstract = {Indinavir (Crivaxan®) is a potent inhibitor of the HIV (human immunodeficiency virus) protease. This enzyme has an important role in viral replication and is considered to be very attractive target for new antiretroviral drugs. However, it becomes less effective due to highly resistant new viral strains of HIV, which have multiple mutations in their proteases. For this reason, we used a lead expansion method to create a new set of compounds with a new mode of action to protease binding site. 1300 compounds chemically diverse from the initial hit were generated and screened to determine their ability to interact with protease and establish their QSAR properties. Further computational analyses revealed one unique compound with different protease binding ability from the initial hit and its role for possible new class of protease inhibitors is discussed in this report.}, subject = {Proteasen}, language = {en} } @article{DandekarBencurovaOsmanogluetal.2021, author = {Dandekar, Thomas and Bencurova, Elena and Osmanoglu, {\"O}zge and Naseem, Muhammad}, title = {Klimapflanzen und biologische Wege zu negativen Kohlendioxidemissionen}, series = {BIOspektrum}, volume = {27}, journal = {BIOspektrum}, number = {7}, issn = {1868-6249}, doi = {10.1007/s12268-021-1677-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-270067}, pages = {769-772}, year = {2021}, abstract = {Climate plants are critical to prevent global warming as all efforts to save carbon dioxide are too slow and climate disasters on the rise. For best carbon dioxide harvesting we compare algae, trees and crop plants and use metagenomic analysis of environmental samples. We compare different pathways, carbon harvesting potentials of different plants as well as synthetic modifications including carbon dioxide flux balance analysis. For implementation, agriculture and modern forestry are important.}, language = {de} } @article{FathyDarwishAbdelhamidetal.2022, author = {Fathy, Moustafa and Darwish, Mostafa A. and Abdelhamid, Al-Shaimaa M. and Alrashedy, Gehad M. and Othman, Othman Ali and Naseem, Muhammad and Dandekar, Thomas and Othman, Eman M.}, title = {Kinetin ameliorates cisplatin-induced hepatotoxicity and lymphotoxicity via attenuating oxidative damage, cell apoptosis and inflammation in rats}, series = {Biomedicines}, volume = {10}, journal = {Biomedicines}, number = {7}, issn = {2227-9059}, doi = {10.3390/biomedicines10071620}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-281686}, year = {2022}, abstract = {Though several previous studies reported the in vitro and in vivo antioxidant effect of kinetin (Kn), details on its action in cisplatin-induced toxicity are still scarce. In this study we evaluated, for the first time, the effects of kinetin in cisplatin (cp)- induced liver and lymphocyte toxicity in rats. Wistar male albino rats were divided into nine groups: (i) the control (C), (ii) groups 2,3 and 4, which received 0.25, 0.5 and 1 mg/kg kinetin for 10 days; (iii) the cisplatin (cp) group, which received a single intraperitoneal injection of CP (7.0 mg/kg); and (iv) groups 6, 7, 8 and 9, which received, for 10 days, 0.25, 0.5 and 1 mg/kg kinetin or 200 mg/kg vitamin C, respectively, and Cp on the fourth day. CP-injected rats showed a significant impairment in biochemical, oxidative stress and inflammatory parameters in hepatic tissue and lymphocytes. PCR showed a profound increase in caspase-3, and a significant decline in AKT gene expression. Intriguingly, Kn treatment restored the biochemical, redox status and inflammatory parameters. Hepatic AKT and caspase-3 expression as well as CD95 levels in lymphocytes were also restored. In conclusion, Kn mitigated oxidative imbalance, inflammation and apoptosis in CP-induced liver and lymphocyte toxicity; therefore, it can be considered as a promising therapy.}, language = {en} } @article{KarlDandekar2013, author = {Karl, Stefan and Dandekar, Thomas}, title = {Jimena: Efficient computing and system state identification for genetic regulatory networks}, series = {BMC Bioinformatics}, volume = {14}, journal = {BMC Bioinformatics}, doi = {10.1186/1471-2105-14-306}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128671}, year = {2013}, abstract = {Background: Boolean networks capture switching behavior of many naturally occurring regulatory networks. For semi-quantitative modeling, interpolation between ON and OFF states is necessary. The high degree polynomial interpolation of Boolean genetic regulatory networks (GRNs) in cellular processes such as apoptosis or proliferation allows for the modeling of a wider range of node interactions than continuous activator-inhibitor models, but suffers from scaling problems for networks which contain nodes with more than ~10 inputs. Many GRNs from literature or new gene expression experiments exceed those limitations and a new approach was developed. Results: (i) As a part of our new GRN simulation framework Jimena we introduce and setup Boolean-tree-based data structures; (ii) corresponding algorithms greatly expedite the calculation of the polynomial interpolation in almost all cases, thereby expanding the range of networks which can be simulated by this model in reasonable time. (iii) Stable states for discrete models are efficiently counted and identified using binary decision diagrams. As application example, we show how system states can now be sampled efficiently in small up to large scale hormone disease networks (Arabidopsis thaliana development and immunity, pathogen Pseudomonas syringae and modulation by cytokinins and plant hormones). Conclusions: Jimena simulates currently available GRNs about 10-100 times faster than the previous implementation of the polynomial interpolation model and even greater gains are achieved for large scale-free networks. This speed-up also facilitates a much more thorough sampling of continuous state spaces which may lead to the identification of new stable states. Mutants of large networks can be constructed and analyzed very quickly enabling new insights into network robustness and behavior.}, language = {en} } @article{StelznerWinklerLiangetal.2020, author = {Stelzner, Kathrin and Winkler, Ann-Cathrin and Liang, Chunguang and Boyny, Aziza and Ade, Carsten P. and Dandekar, Thomas and Fraunholz, Martin J. and Rudel, Thomas}, title = {Intracellular Staphylococcus aureus Perturbs the Host Cell Ca\(^{2+}\) Homeostasis To Promote Cell Death}, series = {mBio}, volume = {11}, journal = {mBio}, doi = {10.1128/mBio.02250-20}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231448}, year = {2020}, abstract = {The opportunistic human pathogen Staphylococcus aureus causes serious infectious diseases that range from superficial skin and soft tissue infections to necrotizing pneumonia and sepsis. While classically regarded as an extracellular pathogen, S. aureus is able to invade and survive within human cells. Host cell exit is associated with cell death, tissue destruction, and the spread of infection. The exact molecular mechanism employed by S. aureus to escape the host cell is still unclear. In this study, we performed a genome-wide small hairpin RNA (shRNA) screen and identified the calcium signaling pathway as being involved in intracellular infection. S. aureus induced a massive cytosolic Ca\(^{2+}\) increase in epithelial host cells after invasion and intracellular replication of the pathogen. This was paralleled by a decrease in endoplasmic reticulum Ca\(^{2+}\) concentration. Additionally, calcium ions from the extracellular space contributed to the cytosolic Ca2+ increase. As a consequence, we observed that the cytoplasmic Ca\(^{2+}\) rise led to an increase in mitochondrial Ca\(^{2+}\) concentration, the activation of calpains and caspases, and eventually to cell lysis of S. aureus-infected cells. Our study therefore suggests that intracellular S. aureus disturbs the host cell Ca\(^{2+}\) homeostasis and induces cytoplasmic Ca\(^{2+}\) overload, which results in both apoptotic and necrotic cell death in parallel or succession. IMPORTANCE Despite being regarded as an extracellular bacterium, the pathogen Staphylococcus aureus can invade and survive within human cells. The intracellular niche is considered a hideout from the host immune system and antibiotic treatment and allows bacterial proliferation. Subsequently, the intracellular bacterium induces host cell death, which may facilitate the spread of infection and tissue destruction. So far, host cell factors exploited by intracellular S. aureus to promote cell death are only poorly characterized. We performed a genome-wide screen and found the calcium signaling pathway to play a role in S. aureus invasion and cytotoxicity. The intracellular bacterium induces a cytoplasmic and mitochondrial Ca\(^{2+}\) overload, which results in host cell death. Thus, this study first showed how an intracellular bacterium perturbs the host cell Ca\(^{2+}\) homeostasis."}, language = {en} } @article{WhisnantJuergesHennigetal.2020, author = {Whisnant, Adam W. and J{\"u}rges, Christopher S. and Hennig, Thomas and Wyler, Emanuel and Prusty, Bhupesh and Rutkowski, Andrzej J. and L'hernault, Anne and Djakovic, Lara and G{\"o}bel, Margarete and D{\"o}ring, Kristina and Menegatti, Jennifer and Antrobus, Robin and Matheson, Nicholas J. and K{\"u}nzig, Florian W. H. and Mastrobuoni, Guido and Bielow, Chris and Kempa, Stefan and Liang, Chunguang and Dandekar, Thomas and Zimmer, Ralf and Landthaler, Markus and Gr{\"a}sser, Friedrich and Lehner, Paul J. and Friedel, Caroline C. and Erhard, Florian and D{\"o}lken, Lars}, title = {Integrative functional genomics decodes herpes simplex virus 1}, series = {Nature Communications}, volume = {11}, journal = {Nature Communications}, doi = {10.1038/s41467-020-15992-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229884}, year = {2020}, abstract = {The predicted 80 open reading frames (ORFs) of herpes simplex virus 1 (HSV-1) have been intensively studied for decades. Here, we unravel the complete viral transcriptome and translatome during lytic infection with base-pair resolution by computational integration of multi-omics data. We identify a total of 201 transcripts and 284 ORFs including all known and 46 novel large ORFs. This includes a so far unknown ORF in the locus deleted in the FDA-approved oncolytic virus Imlygic. Multiple transcript isoforms expressed from individual gene loci explain translation of the vast majority of ORFs as well as N-terminal extensions (NTEs) and truncations. We show that NTEs with non-canonical start codons govern the subcellular protein localization and packaging of key viral regulators and structural proteins. We extend the current nomenclature to include all viral gene products and provide a genome browser that visualizes all the obtained data from whole genome to single-nucleotide resolution. Here, using computational integration of multi-omics data, the authors provide a detailed transcriptome and translatome of herpes simplex virus 1 (HSV-1), including previously unidentified ORFs and N-terminal extensions. The study also provides a HSV-1 genome browser and should be a valuable resource for further research.}, language = {en} }